IPCS INCHEM Home


    PESTICIDE RESIDUES IN FOOD - 1983


    Sponsored jointly by FAO and WHO






    EVALUATIONS 1983





    Data and recommendations of the joint meeting
    of the FAO Panel of Experts on Pesticide Residues
    in Food and the Environment and the
    WHO Expert Group on Pesticide Residues
    Geneva, 5 - 14 December 1983

    Food and Agriculture Organization of the United Nations
    Rome 1985

    PROCHLORAZ

    TOXICOLOGY

    IDENTITY

    Chemical Name(s)

    1-(N-propyl-N-(2-(2,4,6-trichlorophenoxy)ethyl))
    carbamoylimidazole (IUPAC)

    N-propyl-N-[2-(2,4, 6-trichlorophenoxy)ethyl]-1H-imidazole-l-
    carboxamide (American Chemical Society)

    Synonyms

    SPORTAKR, FCB Code No. BTS 40542.

    Structural formula

    CHEMICAL STRUCTURE 1

    Molecular formula C15 H16 Cl3 N3 O2

    Other information on Identity and Properties

    Molecular weight:   376.5

    State               The pure material is a colourless, odourless
                        crystalline solid; the technical material is a
                        white to brown solid.

    Melting point       38.5 - 41.0C

    Vapour pressure     0.57  10-9 Torr at 20C

    Solubility          At 25C 0.055 g/l in water; ca. 16 g/l in
                        kerosene; ca. 2 500 g/l in chloroform, xylene,
                        diethyl ether and toluene; ca. 3 500 g/l in
                        acetone.

    Stability           The stability in aqueous solution is pH-dependent,
                        prochloraz being more stable under slightly acidic
                        conditions than under slightly alkaline
                        conditions. Hydrolysis under alkaline conditions
                        leads to the formation of 
                        N-propyl-N-2-(2,4,6-trichlorophenoxy) ethylamine,
                        the degradation following first order kinetics. At
                        pH 4.95 and pH 6.98 and 22C, no degradation of
                        prochloraz was observed after 30 days. At pH 9.18
                        and 22C, the half-life was 78.9 days. Prochloraz
                        tends to decompose on prolonged heating at high
                        temperatures (ca. 200C).

                        Further information on the stability of prochloraz
                        in soil, water, during processing and storage and
                        on photodecomposition can be found under "Fate of
                        Residues".

    Technical Material and Impurities

         The Meeting was provided with information on impurities in the
    technical material, all of which were said to range from < 0.2
    percent to < 1.2 percent. No evidence has been found for the
    presence of trichlorodibenzo-p-dioxins or tetrachlorobenzofurans and
    all analytical procedures employed have failed to detect (i.e. less
    than 1 ppb) any of the notably toxic 
    2,3,7,8-tetrachlorodibenzo-p-dioxin.

    Identity of Prochloraz-Manganese Complex

    Chemical Name

    tetrakis-{1-[N-propyl-N-[2-(2, 4, 6-trichlorophenoxy)ethyl]]
    carbamoylimidazole} manganese (II) chloride complex.

    Synonyms

    Prochloraz-manganese complex is the trivial name given to the 4:1
    manganese coordination complex of prochloraz. FBC Code No. BTS 46828
    or FBC 31114.

    Structural formula

    CHEMICAL STRUCTURE 2

    Molecular formula C15 H16 Cl3 N3 O2)4 MnCl2

    Other information on Identity and Properties

    Molecular weight    1 632

    Melting point       141-142.5C

    Solubility          At 25C 4 g/l in water, 7 g/l in acetone.

    Stability           The manganese complex is quickly dissociated in 
                        water to give prochloraz. A suspension of the 50
                        percent wettable powder of the manganese complex
                        in distilled water has been shown to dissociate to
                        free prochloraz and manganese chloride to the
                        extent of approximately 55 percent in four hours
                        at 25C. This process is unlikely to be affected
                        greatly at pH 6 to 9 Whiting & Dickson 1979.

    EVALUATION FOR ACCEPTABLE DAILY INTAKE

    BIOCHEMICAL ASPECTS

    Absorption, Distribution and Excretion

    Mouse

         After a single oral dose of 14C-phenyl labelled prochloraz at
    100 mg/kg b.w. was administered to a group of male and female mice,
    the over-all recovery of the given radioactivity was virtually
    complete within 72h. Total recovery was complete (104 percent) with
    urinary excretion (63 percent) being the major route. There were no
    significant sex differences in the rate or route of excretion. Tissue
    residues were highest in liver (5-7 mg/kg) and lowest in muscle,
    genitals, eyes, spleen and fat (0.5-1.0 mg/kg). In all other tissues
    the average value was below 2.5 mg/kg (Needham 1982a).

    Rat

         The excretion rate of prochloraz was monitored for 96 h in three
    male and three female rats administered a single oral dose of 
    14C-phenyl-labelled prochloraz (91 mg/kg b.w.). The over-all recovery
    of the administered radioactivity was 92.7 percent in male and 93.7
    percent in female rate, urinary excretion being the predominant route.
    The mean radioactivity was 61.7 percent in the urine and 30.8 percent
    in the faeces of male rats. It was 54.8 percent in urine and 38.5
    percent in the faeces of female rats. Highest residues, 96 h after
    dosing, were found in the liver (3.7-6.2 mg/kg) and kidney (1.5-2.5
    mg/kg), the tissues of female rats having higher residues (Needham &
    Campbell 1980).

         The chemokinetics were studied over a 96 h period, using an oral
    dose of 100 mg/kg b.w. 14C-imidazole-radiolabelled prochloraz. Male
    rats excreted the administered radioactivity almost quantitatively,
    with approximately 83 percent in the urine, 9 percent in faeces and
    2.4 percent in the expired air. Female rats excreted 56 percent in
    urine, 21 percent in faeces and 1.3 percent in expired air. Plasma
    radioactivity levels reached a peak in male rate approximately 4 h
    after dosing, whereas the levels in female rats remained relatively
    uniform but much lower. Liver radioactivity levels were significantly
    raised within 15 min. and, in the kidney, 30 min. after dosing. They
    generally remained constant for at least 8 h. Significant accumulation
    occurred in brain and adipose tissues, which persisted over 1-8 h and
    then declined markedly between 8 and 24 h. The levels of radioactivity
    in the gastrointestinal tract, 24 h after dosing were significantly
    higher in females compared to males. In general, plasma and tissues
    showed a decline in radioactivity levels over the 96 h period, after 
    which time they reached small, though still significant, levels
    (Turner & Gilbert 1977).

         14C-imidazole ring-prochloraz was administered orally in another
    study at 25 mg/kg b.w./day for 24 days. Residues of prochloraz
    appeared to reach a plateau at about 15 days in the adrenals, ovaries,
    female thyroid and male plasma, while other tissue levels continued to
    increase over the entire 24-day period. The highest residues after
    administration were found in the liver (20.88 ppm males and 25.03 ppm
    females), and the lowest in the fat (2.82 ppm males and 3.72 ppm
    females). The radioactivity was eliminated slowly from tissues,
    significant residues being found after 96 h. Liver and plasma residues
    had a half-life of less than three days and that of muscle was
    approximately 17 days in males and 30 days in females (Hamilton 1978a)

         3H-phenyl-labelled prochloraz was administered daily in another
    study as repeated oral doses of 25 mg/kg for a 20-day period. Plasma
    and tissue radioactivity were measured at specified intervals
    throughout the period of treatment and at 96 h after the last daily
    dose. Plasma levels were higher in males than in females. Tissue
    levels for both sexes rose significantly for the first seven days of
    dosing and thereafter rose only slightly for the remainder of the
    dosing period. Highest levels of radioactivity were found in liver and
    kidney and lowest in muscle and fat. Within 96h after treatment, the
    radiolabelled phenoxy moiety of prochloraz was rapidly eliminated from
    the body without leaving significant tissue residues (Boardman 1979).

    Dog

         A group of two male and two female dogs was given a single oral
    dose of 14C-imidazole-labelled prochloraz at 20 mg/kg b.w., while a
    second group received the same amount of 3H-phenyl-labelled
    prochloraz. There was a marked difference between the plasma
    concentrations of 14C and 3H-labelled prochloraz, suggesting that
    the pesticide was metabolized by fission at the chain linking the
    imidazole and trichlorophenol moieties. The dogs were killed 24 h

    after the administration of the radioactive prochloraz and tissues
    subsequently assayed for radioactivity. Both 14C- and 3H-radio-
    labelled compounds showed high levels in bile and liver (Hamilton
    1978b).

         The distribution and excretion were studied in other groups of
    male and female dogs following a single oral dose of 18 mg/kg b.w. of
    14C-phenyl ring-labelled prochloraz. Peak plasma radioactivity
    occurred 8-24 h after dosing and plasma half life was approximately 72
    h. Excretion was rapid, 60 percent of the dose being eliminated in the
    first 24 h; the over-all recovery after 96 hours was 96 percent with
    faecal excretion as the major route (64 percent of the total dose). No
    sex differences were noted in the rate of excretion or in the
    magnitude of the tissue residues. Highest residues were found in the
    liver and kidney (7.6 and 5.6 mg/kg, respectively) and lowest in bone,
    cerebellum and CSF (less and 1 mg/kg). High residues were present in
    the bile, indicating that biliary excretion represents a significant
    route of elimination in dogs. This finding agrees with the high
    percentage of radioactivity found in the faeces (Needham & Campbell
    1982).

    Goat

         One lactating goat was treated with two oral doses of 14C-phenyl
    prochloraz at 60 mg/kg b.w. given at a 13-day interval. Milk residues
    after the first dose were highest 8 h after dosing (0.04 ppm) and
    declined to 0.01 ppm within 48 h. Plasma residues were highest at 24 h
    (0.33 mg/l), declining to 0.03 mg/l at 13 days. Twenty-four h after
    the second dose, the highest tissue residues were found in the liver
    (1.67 mg/kg), while residues in muscle were minimal (0.03 mg/kg)
    (Campbell 1980).

    Biotransformation

         The biotransformation was studied in a group of male and female
    rats given an oral dose of 100 mg/kg b.w. 14C-imidazole ring-or 
    14C-phenyl ring-labelled prochloraz as a suspension in gum acacia or
    dissolved in maize oil. A similar regimen was followed in separate
    experiments with mice and dogs, except that only 18 mg/kg b.w. of the
    labelled prochloraz was administered to dogs.  Prochloraz was
    extensively metabolized in the rat, with no unchanged compound being
    excreted in the urine. The qualitative and quantitative profiles
    depicted in Figure 1 suggest that metabolism proceeds via cleavage of
    the imidazole ring into 2-carbon fragments, followed by hydroxylation
    of the phenyl ring and/or side chain hydrolysis to form more polar
    compounds. Two main metabolites: 2-(2,4, 6, trichlorophenoxy) ethanol
    (BTS 3037); 2,4,6, trichlorophenoxyacetic acid (BTS 9608) and five
    other minor metabolites were identified. The two main metabolites
    accounted for about 80 percent of the urinary metabolites. A similar
    metabolic pattern was found in the urine of mice, dogs and the female
    goat (Needham 1982b).

    FIGURE 1

    Effects on Enzymes and Other Biochemical Parameters

         In a series of investigations in male rats and mice prochloraz
    was found to be an inducer of hepatic mixed function oxidases (MFO).
    Rats were dosed orally with prochloraz at 10 and 100 mg/kg b.w. twice
    daily for four days and killed 18 h after the last dose. Potent
    induction of MFO occurred at the higher dose, but only a marginal
    effect was seen at the low dose. Relative liver weight and microsomal
    protein concentrations were increased at the high dose. The induction
    spectrum of MFO was similar to that of phenobarbitone, with the levels
    of cytochrome P-450, being increased by both dosages (Needham 1983a).

         A similar MFO induction was noted when male rats were fed
    prochloraz in their diet at 2 500 ppm for seven days. Rats fed a lower
    dose (100 ppm) showed only a small increase in cytochrome P-450
    (Riviere 1983).

         The same pattern of hepatic MFO induction was observed in mice
    after oral administration of doses of 10 and 100 mg/kg b.w. twice
    daily for four days (Challis & Campbell 1983). Prochloraz was an
    inducer of MFO following dietary administration at 325 and 1 300 mg/kg
    in the diet for two weeks. When the compound was administered at 80
    mg/kg for periods in excess of two weeks, the effect was marginal,
    indicating that this concentration is close to the threshold level for
    induction (Needham 1983b).

    Effect of Dog Gastric Juice or Plasma on Prochloraz

         In vitro studies showed prochloraz to be completely stable
    after incubation with dog gastric juice or plasma for 30 min. at 37C
    or for 4 h at 37C. Less than 2 percent underwent hydrolysis. The
    initial step in the metabolism of prochloraz is therefore likely to
    occur in the liver (Needham 1980).

    TOXICOLOGICAL STUDIES

    Special Study on Reproduction

    Rat

         Groups of rats (30 rats of each sex for the Fo generation and 25
    of each sex for the F1 generation) were fed a diet containing 0,
    37.5, 150 or 625 ppm prochloraz (nine weeks for Fo and eight weeks for
    F1) prior to mating and throughout mating, gestation and lactation.
    Two litters per generation were produced for two generations.
    Observations included growth, food consumption, mortality and the
    usual reproduction indices: mating, fecundity, male and female
    fertility, gestation, lactation, pup mortality, litter and mean pup
    weights, viability and terminal studies. In the males (Fo), receiving
    625 ppm in the diet, a prolonged aggression was observed when rehoused
    after both matings; this was not apparent among F1 males. Among Fo
    females, the following overt clinical signs were noted in late

    gestation and/or in the perinatal period: hunched posture, walking on
    toes, piloerection and pallor. Sporadic mortality was recorded at the
    different dose levels and was generally related to dystocia. Food
    intake during the premating period showed no consistent dosage
    relationship for all animals of both generations. However, consumption
    was generally lower than that of the controls. Mean body weight gains
    were depressed only in the premating period in the Fo animals of both
    sexes, given 625 ppm, the same trend being noted during gestation.
    There were no significant effects associated with mating performance
    and pregnancy rate in the treated animals. Some adverse effects on
    gestation periods were noted only at 625 ppm in both generations, with
    a small number of females dying or being killed after exhibiting signs
    of dystocia. There was also an increase in the proportion of females
    with gestation periods in excess of 22 days.

         A small number of females dosed at 625 ppm showed a total loss of
    litters, a lowered mean litter size at birth, increased pup mortality
    at birth and evidence of reduced pup body weight gain in the immediate
    perinatal period at both matings of the Fo animals and at the first
    mating of the F1a animals. A slight lowering of mean litter size at
    both matings was recorded also for the Fo generation fed 150 ppm but
    not for the F1 generation. However, none of the findings were
    significantly different from the controls. At 37.5 ppm, a reduction in
    the mean litter size at birth to day 12 postpartum was noted in the
    first mating of the Fo generation. However, the results were again
    within the range for controls at the testing laboratory.

         No indication of any adverse incidence of structural anomalies
    associated with treatment were recorded at terminal macroscopic
    examination of the remaining F1a and F2a pups and all F1b and F2b
    offspring.

         Increased mean liver weight was recorded in weanling and adult
    F1a males and F2a weanling females given 625 ppm in the diet. In the
    same treated group, mean thymus weight in F1a weanlings of both sexes
    and mean brain weight in the F1a female weanlings was lower than in
    the controls. Microscopic examination of tissues of both sexes from
    weanling F1a and F2a generations and F1a adults selected from
    control and treated groups showed no changes that could be considered
    attributable to exposure to the test compound; 37.5 ppm represented
    the dietary no-effect level (Cozens et al 1982).

    Special Studies on Teratogenicity

    Rat

         Groups of 20 mated Charles River CD rats were given oral doses of
    6, 25 or 100 mg/kg daily from day 1 to 20 post coitum (day 1 was the
    day when sperm was detected in the vaginal smear). A group of 31 rats
    given the vehicle of 10 percent aqueous acacia solution served as
    controls. Body weight, food consumption and overt signs of toxicity
    were recorded throughout the study. The dams were killed on day 21 of
    pregnancy.

         The 25 and 100 mg/kg daily dosage elicited maternal toxicity as
    evidenced by reduced food consumption, lower body weight and liver
    enlargement; in addition, the dams showed increased salivation and
    rubbed their noses in the sawdust litter. The only effect noted in the
    rats given 6 mg/kg was a marginally lower body weight gain. There were
    no macroscopic or microscopic findings attributable to treatment. The
    number of corpora lutea was similar for all groups. The highest
    dosage level appeared to be embryotoxic, as litter size, implantation
    index and viability index were all slightly lower, while the incidence
    of dead foetuses was marginally elevated. In addition, mean foetal
    weight was lower, one litter containing unusually small foetuses that
    appeared to have a gestational age of approximately 19 days. The mean
    placental weight for both the male and female foetuses was higher for
    the 25 or 100 mg/kg treated groups than for the control. A small
    number of foetal abnormalities was noted among the treated groups but
    no consistent pattern and no correlation between incidence and dosage
    level was noted. The degree of calcification of the sternebrae and
    vertebral arches was retarded in foetuses at the 100 mg/kg dose level.
    This dosage elicited toxicity in both dams and embryos but produced no
    teratogenic effects. The 25 mg/kg dosage was toxic in the dams. The
    only findings in the 6 mg/kg group were marginally reduced body weight
    gain and a very slight (non-significant) elevation of placental weight
    (Beswick 1980).

    Rabbit

         Groups of 15 rabbits (New Zealand white strain) were administered
    daily dosages of 0, 3, 12 and 48 mg/kg b.w. of prochloraz by
    intragastric intubation on days 1 to 28 of pregnancy inclusive (day 1
    = day of mating). The control group of 15 rabbits was dosed with the
    vehicle, i.e. 10 percent acacia solution. All surviving dams were
    killed on day 29 of pregnancy for macroscopic examination and the
    foetuses removed for external visceral and skeletal examinations. No
    treatment-related clinical signs and mortality were noted. Food intake
    of the test group remained within 5 percent of the control value, with
    a slightly reduced weight gain in all test groups during the first
    week of dosing. The pregnancy rate was comparable for all groups. A
    significant increase was noted in liver weight, with liver
    discolouration in dams given 48 mg/kg day. A single dam from each of
    the low-and high-dosage groups aborted completely, while one of the
    control dams aborted partially. Litter size, post-implantation loss,
    litter weight and mean foetal weight were considered unaffected by
    treatment. Embryonic and foetal development, as assessed by incidence
    of major malformations, minor anomalies and skeletal variations, were
    similarly unaffected by treatment. No evidence of embryonic
    teratogenic activity was therefore noted in New Zealand white rabbits
    (Palmer et al 1980).

    Special Studies on Mutagenicity

    Ames test

         Purified and technical prochloraz were tested in the Ames test
    against Salmonella typhimurium TA 1535, TA 1537, TA 1538, TA 98 and
    TA 100. All tests were performed in the presence and absence of a
    liver microsome activation system (S-9) derived from 
    phenobarbitone-induced rats and tested at levels of 62.5, 125, 250,
    500 and 1 000 mcg/plate. Positive control mutagens were included in
    all tests to demonstrate the mutability of the bacterial strains and
    the metabolizing capacity of the S-9 preparation; these comprised
    cyclophosphamide, 6-aminochrysene and 2-animofluorene. Dimethyl
    sulphoxide served as the negative control throughout. There was no
    evidence of mutagenic activity against any of the strains employed but
    the antibacterial effects of prochloraz precluded evaluation of
    mutagenicity at concentration of 1 000, 500 and, in some cases, 250
    mcg/plate (Wilcox 1977).

    Micronucleus assay

         Groups of five male and five female Charles River CD rats were
    given two intraperitoneal injections of 6.25, 25.0 or 100 mg/kg b.w.
    of prochloraz 24 h apart. Similar groups were given intraperitoneal
    injections of cyclophosphamide 200 mg/kg b.w. to serve as positive
    controls and intraperitoneal injections of the vehicle (maize oil) as
    the negative controls. Six hours after the second injection all
    animals were killed, smears from the bone marrow of the femur were
    prepared and examined microscopically to determine the incidence of
    micronuclei in the polychromatic erythrocytes. No significant increase
    in the incidence of micronuclei was observed in any of the groups of
    rats. Prochloraz was without clastogenic activity in rats of both
    sexes when tested up to 100 mg/kg b.w. (Everest & Cliffe 1980).

    Dominant lethal test

         Groups of 20 male CD1 strain pathogen-free male mice (age 5-6
    weeks) were given 0, 6, 25 or 100 mg/kg/day prochloraz in the diet for
    eight weeks. After this treatment period, they were paired with
    untreated females on a 1:1 basis for one week and then with a second
    batch of untreated females for a further week. Approximately two weeks
    after the discovery of a vaginal plug or 14 days after the midweek of
    their pairing, the females were killed and their uterine contents
    examined. There were no signs of reaction to treatment and mean weight
    gains of all test groups compared favourably with that of the control
    group. Intergroup variations in mean food consumption throughout the
    entire treatment period were minimal and showed no consistent 
    dosage-related trend.

         Mating performance of treated males and subsequent pregnancy
    rates among untreated females were unaffected by treatment at any
    dosage, except for one male at 25 mg/kg/day, which failed to induce
    pregnancy at either mating. No obvious treatment-related macroscopic
    changes were observed at terminal necropsy of the males. Mean weights
    of the testes of treated males were slightly higher than the control
    value but were not statistically significant. There was no evidence of
    a dose-related effect on the pregnancy rate, mean number of
    implantations, viable young, embryonic death and post-implantation
    losses. Prochloraz showed no evidence of a dominant lethal effect in
    male mice (Cozens et al 1980).

    Mouse lymphoma mutation assay

         Technical prochloraz was tested for mutagenic activity in mouse
    lymphoma cells L5178 Y rendered heterozygous at the thymidine kinase
    (TK) locus. The tests were carried out in the presence and absence of
    a post-mitochondrial supernatant fraction from Arochlor 1254-treated
    male rat livers and the co-factors required for mixed-function oxidase
    activity. In an initial test carried out over a dose range of 0.16
    mcg/ml to 1.6 mg/ml indicated, that prochloraz was toxic to the cells,
    causing extensive cytotoxicity at a concentration of 158 mcg/ml. In
    two further independent experiments at 50.0 mcg/ml and the second at
    70.0 mcg/ml no significant increases in mutation frequency in the
    prochloraz-treated cells over the vehicle control values were
    observed. The concurrent positive control substances were 
    ethyl-methanesulphonate, which does not require the presence of S-9
    mix, and 2-acetylaminofluorene, which requires the presence of S-9 mix
    for metabolism. In both cases, high mutation frequencies were
    obtained.

         Technical prochloraz was not mutagenic to mouse lymphoma L 5178 Y
    cells when tested over a series of dose levels, which extended into
    the toxic range, in the presence or absence of S-9 mix (McGregor 
    et al 1983).

    Special Studies on Carcinogenicity

    Mouse

         Groups of 52 male and 52 female mice CD-1 strain mice were fed
    technical prochloraz in the diet at 78, 325 and 1 300 ppm. For each
    sex, treatment continued until survival reached 20 percent, which was
    106 weeks for males and 121 weeks for females. An additional group of
    104 males and 104 females received the normal diet only. Observations
    included clinical signs, mortality, body weight, food consumption and,
    at 52 weeks and terminally, haematology and weight of selected organs.
    Comprehensive histopathological examinations were made of tissues from
    all surviving animals. Clinical signs were not evident, except in mice
    given 1 300 ppm and in males treated at 325 ppm which were killed
    because of distended abdomens. These animals were subsequently found

    to have multiple liver tumours. No other overt signs of toxicity
    related to treatment were observed. There was no mortality in the
    course of the study attributable to prochloraz. Mice given 1 300 ppm
    showed slightly reduced body weight gain. No differences were noted,
    that were considered to be of toxicological significance, in the
    haematological parameters between treated and control mice. Slightly
    lower haemoglobin concentrations and lower total white blood cell
    counts, due to a lower lymphocyte count, were noted at week 104 in
    female mice treated with 1 300 ppm in diet.

         At necropsy, an increase of liver weights was recorded in both
    sexes given 1 300 ppm prochloraz. There was a dose-related increase in
    the incidence of adenomas and adenocarcinomas of the liver in both
    males and females. At 1 300 and 325 ppm, the increased incidence was
    statistically significant and liver tumours (of hepatocyte origin)
    were observed in both sexes, which were associated in a number of mice
    with more than one tumour. Some cases at 1 300 ppm showed multiple
    tumours as contributory factor to death. At 78 ppm, a slightly higher
    incidence of liver tumours in female mice (6 out of 52) compared to
    controls (5 out of 104) was noted, though the difference was not
    statistically significant. In the males, the incidence of liver
    tumours was similar in controls (37 out of 104) and treated mice (21
    out of 52). There was no evidence of any other effects of treatment in
    terms of either neoplastic or non-neoplastic pathology.

         Treatment of mice was associated with a dose-related increase,
    evident in both sexes, of liver tumours of all types. The incidence of
    liver tumours was statistically significant at 1 300 ppm and 325 ppm
    but not at 78 ppm prochloraz. The dietary dosage of 78 ppm was
    equivalent to 7.5 mg/kg/day in males and 8.8 mg/kg/day in females
    (Colley et al 1983).

    Special Studies on Skin and Eye Irritation

         A moderate to severe skin irritation produced in the rabbit
    suggests that prochloraz is a skin irritant (Kynoch & Liggett 1979a).
    Instillation of dilute solution of prochloraz into the everted lower
    eyelid of one eye of New Zealand white stream rabbits produced a mild
    conjunctival irritation in some animals which persisted up to three
    days (Kynoch & Liggett 1979b).

    Acute Toxicity

         Prochloraz is of low toxicity to rodents when administered
    orally. In rats, the LD50 ranged from 1 600 to 2 400 mg/kg b.w. and
    in mice it was approximately 2 400 mg/kg b.w. Symptoms of intoxication
    became apparent within 30-60 minutes of dosing and included CNS
    depression, respiratory disturbance, ataxia, increased salivation,
    piloerection, increased lacrimation and distended abdomen with signs
    of gastrointestinal irritation. The acute toxicity of prochloraz in
    rodents is summarized in Table 1.

        Table 1.  Acute Toxicity of Prochloraz in Rodents

                                                                                         

    Species    Route                    LD50 (mg/kg)       References
                                                                                         

    Rat        Oral                     1 600-2 400        Carter et al. 1978

    Mouse      Oral                     2 400              Shaw & Carter 1976

    Rat        Dermal                   5 000              Carter 1975

    Rabbit     Dermal                   3 000              Kynoch & Liggett 1979a

    Rat        Inhalation (6h LC50)     >420 mg/cu.m.      Alexander & Clark 1978

    Rat        Intraperitoneal          400-800            Smithson & Lancaster 1980
                                                                                         
    
         In dogs given a single oral dose of 10, 100 or 250 mg/kg b.w. of
    prochloraz, there were no deaths and the only toxic signs were emesis
    and diarrhoea at 100 and 250 mg/kg b.w. (Stobart et al. 1978). One
    female baboon given prochloraz at 50 mg/kg b.w. showed no toxic effect
    while 250 mg/kg b.w. produced only emesis (Morgan et al. 1977).

         Following dermal application to rabbits of 3 000 mg/kg for 24 h
    there were no toxic effects except moderate to severe erythema and
    oedema on the treated skin (Kynoch & Liggett 1979a).

    Short-Term Studies

    Mouse

         Groups of 9 male and 9 female and 15 male and 15 female CD-1
    strain mice were fed prochloraz in the diet at 6, 25, 100 and 400
    mg/kg/day for 6 weeks and 13 weeks, respectively. Groups of 9 or 24
    mice of each sex, given a diet without prochloraz, acted as controls.
    Two additional groups of 15 mice of each sex were given a control diet
    for 17 weeks and a diet containing prochloraz at a nominal dose level
    of 400 mg/kg/day for 13 weeks, followed by a 4-week recovery period.
    Overt signs of toxicity were recorded daily and body weight and food
    consumption three times weekly; haematological and blood biochemistry
    analyses were done at 6 weeks, 13 weeks and 4 weeks off-dose. All mice
    were killed at the end of the dosing or recovery period, examined
    macroscopically, the main organs were weighed and microscopic
    examination of tissues performed.

         No deaths occurred that were attributable to treatment with
    prochloraz. An increased incidence of piloerection occurred in mice of
    both sexes given 400 mg/kg daily. Food consumption of both sexes given
    400 mg/kg daily was higher than that of the controls throughout the
    dosing period and during the first week of the recovery period, but
    was similar to the controls thereafter. A slight weight loss was
    observed in the males given 100 mg/kg daily and in the females given
    400 mg/kg daily. At week 6, haemoglobin concentration, PCV and red
    blood cell counts were increased in both sexes given 400 mg/kg daily;
    MCH was also marginally increased in the females and leucocyte counts
    were increased in females due to lymphocytosis. At week 13 or after
    four weeks recovery, these parameters were no longer affected by
    treatment.

         Plasma GPT activity was increased at week 6 in some mice of both
    sexes given 400 mg/kg daily and some males at 100 mg/kg daily. At week
    13, it was increased in the majority of females given 400 mg/kg daily
    and in some mice of both sexes given 100 mg/kg daily. After four weeks
    recovery, some of the males given 400 mg/kg daily were still affected.
    Albumin content and consequently the albumin:globulin ratio, were
    slightly reduced in both sexes given 400 mg/kg daily and in the males
    given 100 mg/kg daily. At week 13, in both sexes at 400 mg/kg daily,
    urea-nitrogen was slightly decreased and glucose levels were
    increased.

         Liver weight was increased at week 13 in both sexes given 25, 100
    or 400 mg/kg daily. The ovaries in the females and the prostate and
    seminal vesicles in males were small in the group at 400 mg/kg daily.
    After 4 weeks recovery, liver weights were still higher in both sexes
    given 400 mg/kg daily, but to a lesser extent than at weeks 6 and 13.
    Histopathological examination showed minor liver changes with loss of
    glycogen and periportal fat droplets in both male and female mice
    receiving 400 mg/kg and in females receiving 100 mg/kg for 13 weeks.
    Some male mice receiving 100 or 400 mg/kg also showed centrilobular
    hepatocyte enlargement. In both male and female mice killed after four
    weeks recovery, none of these changes were present. The no-effect
    level in mice was 6 mg/kg/day (Gale 1980; Lancaster 1982).

    Rat

         Groups of 20 male and 20 female Boots-Wistar rats were given a
    daily dose of prochloraz by oral gavage in 10 percent aqueous acacia
    suspension at 0, 6, 25 or 100 mg/kg b.w. for 13 weeks. Further groups
    of 20 male and 20 female controls given 100 mg/kg daily of prochloraz
    remained untreated for four weeks after the end of the dosing period
    and, in addition, groups of 10 males and females were given 0, 6, 25
    or 100 mg/kg daily of prochloraz for six weeks. Overt signs of
    toxicity observed in rats of both sexes were increased salivation at
    25 or 100 mg/kg daily and in a few given 6 mg/kg daily. The incidence
    of diarrhoea was increased during the first four weeks of dosing in
    the males given 100 mg/kg daily and possibly in the first week in the
    males given 25 mg/kg daily. In females, a few instances of diarrhoea
    were recorded at each dose level.

         Food consumption was not affected by treatment. However, test
    females gained somewhat more weight than the controls at 25 or 100
    mg/kg daily. At week 6, the only consistent haematological change was
    a decreased haemoglobin concentration in males at each dose level and
    in females given 100 mg/kg daily. A leucocyte count increase was noted
    at each dose level in males due to lymphocytosis. At week 13, MCV was
    slightly decreased at each dose level in the males and haemoglobin
    concentration was slightly decreased in females treated at 25 or 100
    mg/kg daily and in males given 100 mg/kg daily after the four weeks
    recovery period.

         Serum bilirubin was slightly decreased in both sexes at each dose
    level at week 6, in the male at each dose level and in the females
    given 6 or 100 mg/kg daily at week 13. Serum potassium was slightly
    increased at week 6 in the males at 25 or 100 mg/kg and females at 100
    mg/kg daily. UGOT excretion was slightly elevated in a few rats of
    both sexes at each dose level. Urinary protein content was reduced in
    the females at each dose level and in males given 100 mg/kg daily.

         Liver weight at week 6 was increased in both sexes given 100
    mg/kg daily and in the females given 6 or 25 mg/kg daily; kidney
    weight was increased in both sexes given 100 mg/kg daily; spleen
    weight was reduced in the males in each dose group; ovary weight was
    increased in each dose group and thyroid weight was also increased in
    females given 6 or 100 mg/kg daily. After the four-week recovery
    period, the weights of the liver, ovaries and thyroids of the females
    were slightly higher than the control values. The changes in liver
    cell size correlated closely with the increase in liver weight. The
    only instance where such correlation was not apparent was at week 13
    in the females given 6 mg/kg daily, where the centrilobular cells were
    slightly larger but liver weight was unchanged.

         No other findings, that could be related to treatment, were
    observed at microscopic examination of tissues from the rats given 100
    mg/kg daily and killed at week 13. Various treatment-related effects
    were noted in the rats of both sexes given 6 mg/kg daily of prochloraz
    and a no-effect level was therefore not established. However, all
    these effects were marginal (Lancaster & Shaw 1979a).

    Dog

         Groups of four male and four female beagles were given daily
    doses of 1, 2, 5, or 7 mg/kg of prochloraz by gastric intubation for
    13 weeks. Groups of eight males and eight females received 20 mg/kg
    daily or the vehicle (10 percent aqueous acacia solution)
    concurrently. At the end of the dosing period, four males and four
    females from each of the 20 mg/kg and control groups were kept for
    another four weeks without treatment.

         Overt signs of toxicity observed during the dosing period
    included isolated bouts of emesis and increased salivation in some
    dogs from all groups, including controls, although these were more
    prevalent at the high dosage. All dogs at 20 mg/kg daily and one given
    7 mg/kg daily occasionally produced yellow mucoid and/or liquid
    faeces. No effects of treatment were detected on faecal occult blood
    content. During the recovery period, no overt signs of toxicity were
    observed. Reduced food consumption was recorded during the dosing
    period in two dogs given 20 mg/kg daily. Body weight changes during
    the study were comparable in control and treated groups, although
    greater fluctuations were recorded in dogs given 20 mg/kg daily. There
    was no treatment-related effect detected by ophthalmoscopy or
    electrocardiography.

         Transient slight decreases in erythrocyte count and/or
    haemoglobin concentra- were recorded in a few females given 7 or 20
    mg/kg daily. No other treatment-related changes in haematological
    parameters were noted. Changes in the activity of serum enzymes were
    recorded. The serum alkaline phosphatase was high during the dosing
    period in the majority of dogs given 20 mg/kg daily and in some given
    7 mg/kg daily. Serum leucine aminopeptidase was slightly elevated at
    week 6 in some dogs given 20 and in one given 7 mg/kg and serum GPT
    was increased in a dog given 7 mg/kg daily. No change was observed in
    urinary parameters.

         At necropsy, all dogs given 20 mg/kg daily and three given 7
    mg/kg daily had large and heavy livers. Low prostate weights were
    recorded at week 14 in three dogs and in another two dogs in the same
    group at 17 weeks. One of these dogs, killed at week 10, also had
    decreased testes weight. In addition, one dog, given 7 mg/kg daily,
    had a low prostate weight relative to body weight. In two females at
    the high dose killed at week 14, and one killed at week 18, clear
    brown exudate from freshly sectioned mammary glands was observed.
    There were no histopathological findings in dogs on the high
    prochloraz dosage. Counts of liver nuclei revealed no statistically
    significant difference in the cell liver size or in the micronuclei
    count between control and treated dogs.

         In dogs retained for the recovery period, liver size and weight
    returned generally to within normal limits, suggesting that any effect
    of treatment on these parameters was reversible. The changes of AP and
    LAP also returned to normal during the recovery period. The dose
    producing no adverse-effect was 2.27 mg/kg daily (Lancaster et al.
    1979b; Lancaster 1980).

    Long-Term Studies

    Rat

         Groups of 150 male and 150 female rats constituted the controls.
    Two groups each of 80 males and 80 females were treated with 37.5 and
    150 ppm and a further two groups of 90 males and 90 females were given
    625 ppm prochloraz in their diet. When the survival approached 20
    percent in any group, all animals of that sex group were killed (111
    weeks of treatment for females and 115 weeks of treatment in the
    males).

         There were no overt signs of toxicity recorded during the study
    that could be considered related to the treatment. During weeks 20 and
    21, the majority of rats from all groups showed signs indicative of
    sialodacryo-adenitis infection, with a further relapse of mild
    infection in a few rats from each group during the weeks 66 and 67.
    Male survival was similar to controls, while treated females survived
    longer than controls. A lower food consumption with a reduced body
    weight gain was recorded for both sexes given 625 ppm. At 150 ppm,
    food consumption was marginally lower throughout in males and until
    week 52 in the females. Ophthalmoscopic examination revealed no
    abnormalities related to treatment. In a few rats, minor changes were
    seen at week 26, which were considered sequelae of 
    sialodacryo-adenitis infection.

         Periodic laboratory measurements of haematological, biochemical
    and urinalysis parameters in a few treated rats at 625 ppm showed
    changes, but these were minimal and considered of doubtful
    toxicological significance. The changes in urinalysis were minor, i.e.
    lower total protein and changes in the pH. A minimal higher activity
    of serum glutamic oxalacetic transaminase was noted.

         No macroscopic findings related to treatment were seen at interim
    kill in week 13. However, at the 52-week kill, enlarged or swollen
    livers were observed in one male and three females given 150 ppm and
    in four males and one female given 625 ppm in the diet. Heavier livers
    were noted in males and females given 625 ppm diet at week 52 and
    lower pituitary weights were also recorded in a few rats.
    Histopathological examination showed hepatic centrilobular enlargement
    in females given 625 ppm; periportal glycogen loss and centrilobular
    fat deposits were also present in some treated rats of both sexes.
    There were no other microscopic findings related to treatment.

         Enlarged and swollen livers were observed in a higher proportion
    of male rats given 625 ppm than in the controls, and slightly heavier
    liver weights were recorded for females given 625 ppm. The incidence
    of hyperplastic lesions in the liver was slightly higher than in the
    controls in both sexes given 625 ppm, but the differences were not
    statistically significant. The incidence of all other non-neoplastic
    findings was similar in all groups. There was no evidence of
    carcinogenicity from the chronic administration of prochloraz. The 

    no-effect level for toxicological changes was 37.5 ppm, equivalent to
    a mean intake of 1.3 mg/kg/day in males and 1.6 mg/kg/day in females
    (Colley et al. 1982).

    Dog

         Technical prochloraz was fed to groups of five males and five
    females at levels of 0, 30, 135 and 600 ppm (increased to 1 000 ppm
    from week 57) for 104 weeks. Observations included clinical signs,
    mortality, food and water consumption and, at weeks 0, 13, 26, 51, 78
    and 104, ophthalmoscopy, electrocardiography and clinical laboratory
    studies. These comprised haematology, biochemistry, urinalysis and
    faecal occult blood. At necropsy, organs were weighed and
    comprehensive macroscopic and microscopic examinations were carried
    out.

         There were four deaths during the study but none was attributable
    to treatment. There were no overt signs of toxicity or effects of
    treatment upon body weight, food or water consumption, ophthalmoscopic
    or electrocardiographic findings that could be related to treatment.
    There were a few changes in the biochemical parameters, including a
    higher level of SAP for males receiving 600 ppm in the diet during
    week 13 and, during weeks 16 and 50, the elevation was also apparent
    in the females. After the dietary level was increased to 1 000 ppm for
    this group, there was a marked increase in the SAP levels during week
    60, which persisted throughout the rest of the dosing period. The mean
    level for males receiving 135 ppm was also higher than the control
    mean from week 13 onwards, but the difference was not so marked as at
    600 ppm. There was a slight but inconsistent increase in the platelet
    count, glucose and cholesterol values in the group receiving 600 to
    1 000 ppm, but these could not be related definitely to treatment.
    There was no effect of treatment on the urinary parameters or faecal
    occult blood content.

         Liver weights in five animals that received 600 to 1 000 ppm, one
    that received 135 ppm and one control, when expressed as a percentage
    of body weight, exceeded the normal upper limit. The mean prostate
    weight for animals in the same treatment group was significantly lower 
    than the control mean weight.

         Histopathological examination showed minimal prostatic atrophy,
    low grade hepatitis and minimal swelling and rarefaction of
    centrilobular hepatocytis at 600 to 1 000 ppm. One male dog given 135
    ppm also showed some liver changes. There were no other
    histopathological changes related to prochloraz.

         The no-effect level was 30 ppm in the diet, equivalent to
    approximately 0.92 mg/kg/day (Chesterman et al. 1981).

    Observations in Humans

         Prochloraz has been produced on a commercial scale since 1980. No
    adverse human effects have been detected since then from synthesis 
    formulation or use of prochloraz or its formulation. No clinical or
    laboratory data were included (Bonsall 1982).

    COMMENTS

         Prochloraz has low oral toxicity. Following oral administration
    in the rat, 95 percent of the dose is rapidly absorbed. In rats, the
    major excretion is via the urine; in dogs it is via the faeces.
    Prochloraz is a demonstrated liver mixed function oxidase inducer.

         In rats and rabbits, no evidence of teratogenic effects was noted
    at maternally toxic dose levels. A multigeneration reproduction study
    in rats did not show any adverse effects at doses up to 37.5 ppm.
    Mutagenicity studies, including the Ames test, micronucleus test,
    mouse lymphoma assay and a dominant lethal study, were all negative.

         In 90-day studies in mice, rats and dogs, liver weight was
    increased in all species. No-effect levels of 6 mg/kg/day and of 2.27
    mg/kg/day were established for mice and dogs, respectively. However,
    in rats 6 mg/kg/day induced increased liver weight and occasional
    signs of intoxication (increased salivation, diarrhoea). A two-year
    dog study established a no-effect level of 30 ppm.

         A long-term rat study did not result in any evidence of oncogenic
    potential. A no-effect level of 37.5 ppm in the diet was established.
    A mouse carcinogenicity study of 106 weeks duration indicated an
    increased incidence of liver adenomas and adenocarcinomas in both
    sexes at dose levels of 325 ppm and above. Prochloraz has been shown
    to be a hepatocarcinogen in mice.

    TOXICOLOGICAL EVALUATION

    Level Causing no Toxicological Effect

    Rat (male);    37.5 ppm in the diet, equal to 1.3 mg/kg b.w.

    Dog:           30 ppm in  he diet, equal to 0.9 mg/kg b.w.

    Estimate of Acceptable Daily Intake for Man

    0 - 0.01 mg/kg b.w.

    FURTHER WORK OR INFORMATION

    Desirable

    Observations in humans.

    REFERENCES-TOXICOLOGY

    Alexander, D.J. & Clark, G.C. Preliminary acute inhalation toxicity
    1978      study in male and female rats with pure prochloraz (single
              exposure). Report TX78053 from Huntingdon Research Centre
              and Boots, submitted to WHO by FBC Ltd. (Unpublished)

    Boardman, L.E. Plasma and tissue distribution studies in the rat
    1979      following single and repeated oral doses of 3H-prochloraz.
              Report AX79004 from Hazleton and Boots submitted to WHO by
              FBC Ltd. (Unpublished)

    Beswick, A.M. The teratogenicity study of technical prochloraz in male
    1980      and female rats. Report TX80024 from Boots submitted to WHO
              by FBC Ltd. (Unpublished)

    Bonsall, J.L. The human exposure to prochloraz since synthesis in 1974
    1982      and commercial production in 1980. Report submitted to WHO
              by FBC Ltd. (Unpublished)

    Campbell, J.K. Residues in milk and tissues of a goat dosed orally
    1980      with 14C-prochloraz. Report AX80026 from Boots submitted to
              WHO by FBC Ltd. (Unpublished)

    Carter, O.A. Acute dermal toxicity of prochloraz to the male Boots
    1975      Wistar rat. Report TXM75079 from Boots submitted to WHO by
              FBC Ltd. (Unpublished)

    Carter, O.A., Smithson, A. & Burnett, R. Acute oral toxicity of
    1978      prochloraz, prochloraz pure material, stage 3 and stage 4
              technical material and mother liquor concentrate impurities
              to male Boots Wistar rats. Report TX78118 from Boots
              submitted to WHO by FBC Ltd. (Unpublished)

    Challis, I.R. & Campbell, J.K. The effect of prochloraz on the hepatic
    1983      mixed function oxidase system of the male mouse after oral
              administration. Report METAB/83/6 from FBC submitted to WHO
              by FBC Ltd. (Unpublished)

    Chesterman, H. et al. Two-year toxicity study in beagle dogs of
    1981      technical prochloraz - final report - repeated dietary
              administration for 104 weeks. Report TOX/81/173-2 from
              Huntingdon Research Centre and FBC submitted to WHO by FBC
              Ltd. (Unpublished)

    Colley, J. et al. Prochloraz chronic toxicity and carcinogenicity
    1982      study in rats by dietary administration - 104 weeks (final
              report). Report TOX/82/173-8 from Huntingdon Research
              Centre, and FBC submitted to WHO by FBC Ltd. (Unpublished)

    Colley, J. et al. Prochloraz tumorigenicity study in mice by dietary
    1983      administration (final report). Report TOX/83/173/23 from
              Huntingdon Research Centre and FBC submitted to WHO by FBC
              Ltd. (Unpublished)

    Cozens, D.D., Reid, Y.J., Woodhouse, R.N., Almond, R.H. Anderson, J.
    1980      & Ball, S.I. Dominant lethal gene assay of technical
              prochloraz in the male mouse. Report TX80077 from the
              Huntingdon Research Centre and Boots submitted to WHO by FBC
              Ltd. (Unpublished)

    Cozens, D.D. et al. The effect of prochloraz on reproductive
    function
    1982      of multiple generations in the rat. Report TOX/82/173-5 from
              Huntingdon Research Centre and FBC submitted to WHO by FBC
              Ltd. (Unpublished)

    Everest, R.P. & Cliffe, S. Technical prochloraz micronucleus assay in
    1980      male and female CD rats of prochloraz. Report TX80003 from
              Boots submitted to WHO by FBC Ltd. (Unpublished)

    Gale, E.P. 90-day oral toxicity study with prochloraz technical to
    1980      male and female CD1 mice. Report TX80040 from Hazleton and
              Boots submitted to WHO by FBC Ltd. (Unpublished)

    Hamilton, D.Y. The distribution and level of 14C-labelled residues in
    1978a     rats following repeated oral dosing with 14C-prochloraz at
              25 mg/kg/day. Report AX78008 from Boots submitted to WHO by
              FBC Ltd. (Unpublished)

    Hamilton, D.Y. The distribution and level of radiolabelled residues in
    1978b     the tissues of the dog following a single oral dose of
              prochloraz. Report AX78016 from Boots submitted to WHO by
              FBC Ltd. (Unpublished)

    Kynoch, S.R. & Liggett, M.P. Primary eye irritancy of prochloraz 40
    1979a     percent E.C. formulation (bfn 8099). Report TX79050 from
              Huntingdon Research Centre and Boots submitted to WHO by FBC
              Ltd. (Unpublished.)

    Kynoch, S.R. & Liggett, M.P. Primary skin irritancy of prochloraz 40
    1979b     percent E.C. formulation (bfn 8099). Report TX79074 from
              Huntingdon Research Centre and Boots submitted to WHO by FBC
              Ltd. (Unpublished)

    Lancaster, M.C. & Shaw, J.W. 90-day oral toxicity study with
    1979a     prochloraz technical in male and female Boots Wistar rats
              (4-week off-dose period). Report TX79028 from Boots
              submitted to WHO by FBC Ltd. (Unpublished)

    Lancaster, M.C., Morgan, H.E. & Stobart, J.E. 90-day oral toxicity
    1979b     study with prochloraz technical in male and female beagle
              dogs (4-week off-dose period). Report TX79010 from Boots
              submitted to WHO by FBC Ltd. (Unpublished)

    Lancaster, M.C. 13-week oral toxicity study with prochloraz technical
    1980      (BX 9/DM 2723) in male and female dogs with a four-week 
              off-dose period. Histopathological examination of the
              remaining tissues. Report TX80034 from Boots submitted to
              WHO by FBC Ltd. (Unpublished)

    Lancaster, M.C. PRochloraz: 13-week oral toxicity in the mouse -
    1982      histopathological examination. Report TOX/82/173/-9 from FBC
              Ltd. submitted to WHO by FBC Ltd. (Unpublished)

    McGregor, D.B., Riach, C.G. & Brown, A.G. Technical prochloraz
    1983      assessment of mutagenic potential in the mouse lymphoma
              mutation assay. Report TOX/83/173-22 from Inveresk and FBC
              submitted to WHO by FBC Ltd. (Unpublished)

    Morgan, G.E., Patton, D.S.G., Shepherd, G.M. & Stobart, J.E. The acute
              oral toxicity of bts 40542 (technical batch) to the female
              baboon. Report from Boots Laboratories submitted to WHO by
              FBC Ltd. (Unpublished)

    Needham, D. The effect of dog gastric juice or plasma on prochloraz.
    1980      Report AX80011 from Boots submitted to WHO by FBC Ltd.
              (Unpublished)

    Needham, D. & Campbell, J.K. The excretion of 14C-phenyl-labelled
    1980      prochloraz in male and female rats after a single oral dose.
              Report AX80037 by Boots submitted to WHO by FBC Ltd.
              (Unpublished)

    Needham, D. The excretion and tissue residues of 14C-prochloraz in
    1982a     male and female mice following a single oral dose of 100
              mg/kg. Report METAB/82/32 from FBC submitted to WHO by FBC
              Ltd. (Unpublished)

    Needham, D. & Campbell, J.K. The excretion and tissue residues of 14C
    1982      prochloraz in male and female dogs following a single oral
              dose of 18 mg/kg. Report METAB/82/30 by FBC submitted to WHO
              by FBC Ltd. (Unpublished)

    Needham, D. The metabolism of prochloraz in the rat after oral
    1982b     administration. Report METAB/82/31 from FBC submitted to WHO
              by FBC Ltd. (Unpublished)

    Needham, D. The effect of prochloraz on the hepatic mixed-function
    1983a     oxidase system of the male rat after oral administration.
              Report METAB/83/5 from FBC submitted to WHO by FBC Ltd.
              (Unpublished)

    Needham, D. The effect of prochloraz on the hepatic mixed function
    1983b     oxidase system of the mouse when administered at 80, 325 and
              1 300 mg/kg diet for up to 14 weeks. Report METAB/83/7 from
              FBC submitted to WHO by FBC Ltd. (Unpublished)

    Palmer, A.K., Bottemley, A.M. & Billington, R. The effect of technical
    1980      prochloraz on pregnancy of the New Zealand white rabbit.
              Report TX80083 from Huntingdon Research Centre and Boots
              submitted to WHO by FBC Ltd. (Unpublished)

    Rivire, J.L. Prochloraz, a potent inducer of the microsomal
    1983      cytochrome P-450 system. Pestic. Biochem. Physiol., 19: 
              44-52.

    Shaw, J.W. & Carter, O.A. Acute oral toxicity to male CD 1 mice of
    1976      prochloraz. Report TX76093 from Boots submitted to WHO by
              FBC Ltd. (Unpublished)

    Smithson, A. & Lancaster, M.C. Acute intraperitoneal toxicity of
    1980      prochloraz to male CD rats. Report TX80004 from Boots
              submitted to WHO by FBC Ltd. (Unpublished)

    Stobart, J.E., Morgan, H.E., Patton, D.S.G. & Shepherd, G.M. Acute
    1978      oral toxicity of prochloraz to male and female beagle dogs.
              Report TX78049 from Boots submitted to WHO by FBC Ltd.
              (Unpublished)

    Turner, D.M. & Gilbert, C.M. Pharmacokinetic studies on 14C-labelled
    1977      prochloraz in the rat. Report AX77001 from Hazleton and
              Boots submitted to WHO by FBC Ltd. (Unpublished)

    Wilcox, P. Prochloraz in vitro bacterial mutagenicity testing of
    pure
    1977      and technical prochloraz. Report TX78002 from Boots
              submitted to WHO by FBC Ltd. (Unpublished)

    RESIDUES

    RESIDUES IN FOOD AND THEIR EVALUATION

    USE PATTERN

         Prochloraz is available as 40 percent and 45 percent emulsifiable
    concentrate (E.C.) formulations for foliar and postharvest treatments
    and is sold under the trademark Sportak. A 50 percent wettable powder
    formulation containing a 4:1 prochloraz-manganese coordination complex
    active ingredient (a.i.) (3.4 percent manganese) is available and
    recommended for foliar application to some broad leaf crops,
    ornamentals and mushrooms, which may be susceptible to phytotoxicity
    from E.C. formulations. Prochloraz is available in co-formulation with
    carbendazim, under the trademarks Sportak PF and Sportak ALPHA, for

    foliar application to cereal and oilseed rape. A 200 g/l liquid
    formulation is available for cereal seed treatment and a 25 percent
    E.C. disinfectant for rice seed.

         Prochloraz is used for the control of a variety of fungal
    diseases on a variety of crops and is said to be especially active
    against Ascomycetes and Fungi Imperfecti. It is currently registered
    or approved for use in eight countries and similar measures are
    pending or planned in many others. Nationally registered and/or
    approved uses are summarized in Table 1.

    RESIDUES RESULTING FROM SUPERVISED TRIALS

         Residue trials have been conducted in many countries,
    representing a wide range of food crops, climatic conditions,
    formulations and foliar, seed and postharvest treatments. Trials data
    are summarized in Tables 2-13. Trials data from countries with
    approved uses are available only for apples, watermelons, grapes
    (Taiwan, province of China), cereal (Belgium, Denmark, France, German
    Federal Republic, The Netherlands, United Kingdom) and mushrooms (The
    Netherlands).

    Sugarbeets

         No information was available on good agricultural practices for
    prochloraz on sugarbeets. The "recommended" application rate of active
    ingredient is said to be 0.5-1 kg/ha for foliar treatment. No
    preharvest interval (PHI) is given. Total residues of both free and
    conjugated residues of prochloraz (BTS 40 542), 
    N-formyl-N'-propyl-N'-2(2,4,6-trichlorophenoxy) ethylurea (BTS 44596),
    N-propyl-N-2 (2,4,6-trichlorophenoxy) ethylurea (BTS 44595) and 
    2,4,6-trichlorophenol (BTS 45186), hereafter referred to as total
    residues of prochloraz and metabolites, are listed in Table 2. The
    values (corrected for 90 percent recoveries) are expressed as
    prochloraz equivalents but were determined as 2,4,6-trichlorophenol
    after hydrolysis. All residues and the 0.036 mg/kg control are below
    the limit of determination, said to be 0.1 mg/kg. Data are
    insufficient to support a maximum residue level, even if good
    agricultural practices were known.

         The "recommended" application rate of active ingredient to
    sugarbeet leaves is said to be 0.5-1 kg/ha for foliar treatment. No
    PHI was provided. Total residues of prochloraz and metabolites,
    expressed as prochloraz equivalents, on sugarbeet leaves were 0.97,
    1.3 and 1.2 mg/kg at 5, 21 and 42 days, respectively, after the last
    treatment in three trials (Table 2). The control was 0.15 mg/kg.

    Lettuce

         No information was available on good agricultural practices on
    lettuce. Residues of prochloraz only, uncorrected for approximately 72
    percent recoveries, ranged from 7.4 mg/kg 18 days after treatment to
    0.41 mg/kg after 39 days and <0.07 mg/kg after 71 days with a limit

    of sensitivity said to be 0.01 mg/kg, although one of the three
    controls has apparent residues of 0.02 mg/kg. Recoveries were 65-76
    percent at 0.1-0.5 mg/kg fortification levels.

    Watermelons

         Residue data reflecting good agricultural practices in Taiwan
    Province of China are presented in Table 2. Residues of prochloraz 
    per se were 0.01 mg/kg in peel and flesh after the approved six-day
    interval from last application to harvest. Information was not
    provided on the analytical procedure used; a 0.003 mg/kg limit of
    detection was claimed.

    Citrus Fruits

         No information was provided on good agricultural practices on
    citrus fruits. Residues from postharvest trials, proposed for uses
    (25-70 g/hl for dip treatments or 100-300 g/hl for spray treatments)
    where the peels are discarded, are summarized in Table 3. A variety of
    treatment and storage conditions are given, representing 23 trials in
    five countries. In some cases prochloraz alone is determined, in
    others prochloraz and its metabolites and in one case BTS 45 186. 
    Total residues are generally expressed as prochloraz equivalents,
    although they are usually measured as BTS 45 186. Total residues after
    storage at ambient of 4C for up to 70 days and from a variety of
    treatments and locations ranged up to 18 mg/kg in peel, 0.44 mg/kg in
    flesh and 6 mg/kg on a whole fruit basis. Residue levels of free
    prochloraz were not substantially different than those for total
    residues, where a comparison was made. More details are reported under
    "Fate of Residues, Storage and Processing".

    Pome Fruits

         Information on good agricultural practice and residue data
    (prochloraz only) reflecting such practice on apples are available for
    Taiwan Province of China, as well as data for apples and pears from
    supervised trials in three additional countries for which good
    agricultural practices for prochloraz on pome fruit are not known.

    Apples

         The most pertinent data were those from Taiwan Province of China,
    for which information was available on good agricultural practices on
    apples. Data represent recommended and 2X the recommended application
    rate. No data were available for the recommended 9-day last treatment
    to harvest interval, but they were given for 6 and 12 days. Residues
    of prochloraz, per se, from nine applications were 0.07 and 0.01
    mg/kg, respectively, at these intervals from the recommended
    application rate. No information is available on the analytical method
    used other than a claimed 0.003 mg/kg limit of detection. Other apple
    residue data (parent compound only) are from application rates three
    to eight times that for good agricultural practice known to the
    Meeting. Over-all recoveries among studies submitted range from 64-92

    percent with claimed sensitivities ranging from 0.001-<0.01 mg/kg.
    Apparent residues in untreated controls, where given, are 
    <0.01-0.02 mg/kg. A reasonable limit of determination would appear
    to be about 0.1 mg/kg. One study (Hayto 1977c) indicates a half-life
    in apples of 6-7 days.

    Pears

         No information on good agricultural practice was available for
    pears. The application rates are substantially greater than known good
    agricultural practice for apples and residues are higher, as would be
    expected.

    Stone Fruits

         No information on good agricultural practice for prochloraz on
    stone fruit were available to the Meeting. The "recommended"
    application rate for foliar treatment with the prochloraz-50 percent
    W.P. manganese complex formulation was reported as 15-30 g a.i./hl. No
    preharvest interval was given. Residue data were available on
    apricots, nectarines, peaches, cherries and plums from four countries
    (Table 2). Total residues of prochloraz and the metabolites were
    determined as 2,4,6-trichlorophenol and expressed as prochloraz.
    Residues in mature fruit ranged from a maximum of 0.19 mg/kg im plums
    at 3 days, 1 mg/kg at 14 days, 0.82 mg/kg at 24 days to <0.05 mg/kg
    over 75 days after multiple foliar treatments with either E.C. or W.P.
    (manganese complex) formulations. Residues were generally lower for
    other stone fruit at comparable intervals after treatment with the
    W.P. formulations. At fortification levels of 0.05-1 mg/kg recoveries
    are 70-113 percent over-all. Apparent residues in eight untreated
    stone fruit controls were 0.009-0.022 mg/kg except one value of 0.06
    mg/kg in four controls (plums). The limit of determination for stone
    fruit was reported as 0.05 mg/kg.

    Grapes

         Information on good agricultural practice for the E.C.
    formulation and residue data reflecting 1, 1.5, 2 and 4X recommended
    application rates were available from one country.

         Residues from two applications at recommended rates ranged from
    0.39 mg/kg on the day of application to <0.01 mg/kg after 21 days and
    0.1 mg/kg at the recommended 9-day preharvest interval. Higher
    application rates and numbers of applications, with one or two
    exceptions, did not make an appreciable difference in the residue
    level at comparable intervals after application. No information was
    provided on apparent residues in un-treated controls or on the
    analytical procedure; a 0.003 mg/kg limit of detection was reported.


        TABLE 1.  REGISTRATIONS AND APPROVED USES FOR PROCHLORAZ

                                                                                                                                           

    Country        Product1       Commodity     Approved Application Rate      Number and timing of                         Pre-harvest
                                                Product         a.i.           Applications                                 Interval
                                                                (prochloraz)
                                                                                                                                           

    Belgium        SPORTAK 45EC   Winter        1 l/ha          0.45 kg/ha     One application at earstage in mixture       na
                                  wheat                                        with either 0.125 kg/ha carbendazim,
                                                                               1.2 kg/ha captafol or 1.6 kg/ha maneb.

                                  Winter
                                  barley        1 l/ha          0.45kg/ha      One application at stage L or M2

    Denmark        SPORTAK        Barley        100 ml/100 kg   0.2 g/kg       na                                           na
                   BEJOSE         (seed
                                  dressing)

                   SPORTAK 45EC   Spring        1 l/ha          0.45 kg/ha     One application at stage 4-10.5 or a
                                  barley                                       split dose at half rate with the first
                                                                               application at stage 4-6 and the second
                                                                               at stage 8-10.53.

                                  Winter        1 l/ha          0.45 kg/ha     One (stage 4-10.5) or two (stage 4-6         cereals
                                  barley                                       and 7-10.5) applications3.                   1 month

                                  Winter        1 l/ha          0.45 kg/ha     Two applications (stages 5-6 and 9-
                                  wheat                                        10.53).

                                  Winter        1 l/ha          0.45 kg/ha     One application (stages 5-7)3
                                  rye

    Eire           SPORTAK 40EC   Cereals       1 l/ha          0.4 kg/ha      Up to three applications between leaf
                                                                               sheaf erection and complete ear emergence.   na
                                                                                                                                           

    Table 1 (continued)

                                                                                                                                           

    Country        Product1       Commodity     Approved Application Rate      Number and timing of                         Pre-harvest
                                                Product         a.i.           Applications                                 Interval
                                                                (prochloraz)
                                                                                                                                           

    France         SPORTAK 40EC   Wheat         1.125-1.875     0.45-0.75      Up to two applications (stages 6-7
                                                l/ha            kg/ha          and 10.3-10.5)3

                                  Barley        1.125 l/ha      0.45 kg/ha     Up to two applications (stages 6-7
                                                                               and 10.1)3                                   na

                   SPORTAK 45EC   Wheat         1-1.66 l/ha     0.45-0.75      Up to two applications (stages 6-7
                                                                kg/ha          and 10.3-10.5)3.

                                  Barley        1 l/ha          0.45 kg/ha     Up to two applications (stages 6-7
                                                                               10.1)3

                   SPORTAK PF     Wheat         1.5 l/ha        0.45 kg/ha     Up to two applications (stages 6-7
                                                                               and 10.3-10.5)3.

                                  Barley        1.5 l/ha        0.45 kg/ha     Up to two applications (stages 6-7
                                                                               10.1)3.

                                  Oil seed      1.5 l/ha        0.45 kg/ha     Up to two applications, at beginning
                                  rape                                         and end of flowering.                        na

                   SPORTAK M      Wheat         1.125 l/ha      0.45 kg/ha     Up to two applications (stages 6-7
                                                                               and 10.3-10.5)3.

                                  Barley        1.125 l/ha      0.45 kg/ha     Up to two applications (stages 6-7
                                                                               10.1)3.

                                                                                                                                           

    Table 1 (continued)

                                                                                                                                           

    Country        Product1       Commodity     Approved Application Rate      Number and timing of                         Pre-harvest
                                                Product         a.i.           Applications                                 Interval
                                                                (prochloraz)
                                                                                                                                           

    German         SPORTAK 40EC   Wheat         1.2 l/ha        0.48 kg/ha     One (stage 29-32) or two
    Federal                                                                    (stages 29-59) applications5.
    Republic                                                                                                                Cereals -
                                  Barley        1.2 l/ha        0.48 kg/ha     One (stage 29-32) or two                     35 days6
                                                                               (stages 29-49) applications5.

                                  Winter        1.2 l/ha        0.48 kg/ha     One application at stage 29-325.
                                  rye                                          Restricted to a maximum of three
                                                                               applications in Winter cereal.

    Netherlands    SPORTAK 45EC   Wheat         1 l/ha          0.45 kg/ha     1-2 treatments after infection.

                                  Barley        1 l/ha          0.45 kg/ha     1-2 treatments after infection.              Cereals -
                                                                                                                            8 weeks7
                                  Winter        1 l/ha          0.45 kg/ha     One or two applications.
                                  barley

                                  Ornamentals   0.4%            180 g/hl       Flower bulb dip                              na

                   SPORGON        Mushrooms     3/g/l/m2        1.5g/l/m2      One application of casing soil               Mushrooms -
                                                                               nine days after casing.                      10 days

    Taiwan         SPORTAK 25EC   Rice          2000 x          12.5 g/hl      24 hour rice seed soak.                      na
                                                dilution

                                  Grape         6000 x          4.17 g/hl      Two to three applications,                   Grape -
                                                dilution                       every 10 days.                               9 days

                                  Apple         3000 x          8.33 g/hl      Application every 10 days.                   Apple -
                                                dilution                                                                    9 days

                                                                                                                                           

    Table 1 (continued)

                                                                                                                                           

    Country        Product1       Commodity     Approved Application Rate      Number and timing of                         Pre-harvest
                                                Product         a.i.           Applications                                 Interval
                                                                (prochloraz)
                                                                                                                                           

                                  Watermelon    4000 x          6.25 g/hl      10 days.                                     6 days
                                                dilution

    United         SPORTAK 40EC   Cereals       1 /ha           0.4 kg/ha      Up to three applications between             na
    Kingdom                                                                    leaf sheath erection and complete
                                                                               ear emergence.

                                  Oil seed      1.25 l/ha       0.5 kg/ha      Up to three applications between
                                                                               stem extension and 90% petal fall.

                                  Ornamentals   -               2000 ppm       Propagation cutting dip, drench,             na
                                                                               foliar spray or compost incorporation.

                   SPORTAK 45EC   Cereals       1 /ha           0.45 kg/ha     Up to three applications between             na
                                                                               leaf sheath erection and complete
                                                                               ear emergence.

                                  Oil seed      1-1.33 /ha      0.45-0.6       Up to three applications between
                                  rape                          kg/ha          stem extension and 90% petal fall.

                                  Ornamentals   -               2000 ppm       Propagation cutting dip, drench,             na
                                                                               foliar spray or compost incorporation.

                   SPORTAK        Cereals       1.5 /ha         0.4 kg/ha      Up to three applications between
                   ALPHA                                                       leaf sheath erection and complete
                                                                               ear emergence.                               na

                                  Oil seed      1.5 /ha         0.4 kg/ha      Up to three applications between
                                  rape                                         stem extension and 90% petal fall.

                                                                                                                                           

    Table 1 (continued)

                                                                                                                                           

    Country        Product1       Commodity     Approved Application Rate      Number and timing of                         Pre-harvest
                                                Product         a.i.           Applications                                 Interval
                                                                (prochloraz)
                                                                                                                                           

                                  Ornamentals   -               2000 ppm       Propagation cutting dip, drench,             na
                                                                               foliar spray or compost incorporation.

                   SPORTAK FE     Cereals       4 kg/ha         0.66 kg/ha     Up to three applications between
                                                                               leaf sheath erection and complete
                                                                               ear emergence.                               na

                                  Oil seed      3 kg/ha         0.5 kg/ha      Up to three applications between
                                  rape                                         stem extension and 90% petal fall.

                                  Ornamentals   -               2000 ppm       Propagation cutting dip, drench,             na
                                                                               foliar spray or compost incorporation.

                   SPORGON        Mushrooms     3 g/l/m2        1.5 g/l/m2     One application, 1-10 days after             Mushrooms -
                                                                               casing.                                      10 days

                                                0.6 g/l/m2      0.3 g/l/m2     Three applications, one 1-10 days            Mushrooms -
                                                                               after casing and then after the              2 days
                                                                               first and second flush

                                                1.2 g/l/m2      0.6 g/l/m2     Two applications, one 1-10 days              Mushrooms -
                                                                               after casing and then between                2 days
                                                                               second and third flush.

                                  Ornamentals   -               2000 ppm       Propagation cutting dip, drench,             na
                                                                               foliar spray or compost incorporation.

                                                                                                                                           

    Table 1 (continued)


    Notes:    na - not applicable
              nd - not defined
              ns - not specified

    1.   The following formulations have been registered:

         SPORTAK 40 EC  - an emulsifiable concentrate containing 400 g/l prochloraz
         SPORTAK 45 EC  - an emulsifiable concentrate containing 450 g/l prochloraz
         SPORTAK BEJDSE - a liquid seed dressing containing 200 g/l prochloraz
         SPORTAK PF     - an emulsifiable concentrate containing 300 g/l prochloraz and 80 g/l carbendazim
         SPORTAK M      - a twin-pack emulsifiable concentrate containing 400 g/l prochloraz and 450 g/l mancozeb
         SPORTAK ALPHA  - an emulsifiable concentrate containing 266 g/l prochloraz and 100 g/l carbendazim
         SPORTAK FE     - a wettable powder containing 165 g/kg prochloraz-manganese complex and 533.4 g/kg mancozeb
         SPORGON        - a wettable powder containing 500 g/kg prochloraz-manganese complex

    2.   Baggiolini cereal growth stages.

    3.   Feekes-Large cereal growth stages.

    4.   Residues of prochloraz alone.

    5.   Zadoks Decimal cereal growth stages.

    6.   A proposed MRL of 0.5 mg/kg for prochloraz and metabolites in cereal grain has been submitted.

    7.   Under review, pending further residue analysis.

    8.   Residues of prochloraz and metabolites measured as 2,4,6-trichlorophenol and expressed as prochloraz.

    Table 2   Prochloraz Residues in Various Crops Following Supervised Trials

                                                                                                                                      

                   Country/         No. of  Formulation  Application     Interval after     Residues,   Reference
    Crop           Year             trials               rate (a.i.)     final application  (mg/kg)1
                                                                         (days)
                                                                                                                                      

    Sugarbeet      Italy
    root           1981             1       40% E.C.     2 x 1 kg/ha     42-46              0.02        Longland 1983b
    leaves                                                                                  1.17
    root                            1       40% E.C.     3 x 1 kg/ha     21-25              0.04
    leaves                                                                                  1.32
    root                            1       40% E.C.     4 x 1 kg/ha     5-6                0.06
    leaves                                                                                  0.97

    Lettuce        The Netherlands  1       8% dust      8 kg/ha         70-73              0.013       Hayto 1979d
                   1978                                                  80                 0.013
                                    2       8% dust2     8 kg/ha         18-19              7.383
                                                                         39                 0.043
                                                                         42-46              0.123
                                                                         70-73              <0.013
                                                                         80                 <0.013
                                    1       8% dust2     6.4 kg/ha       70-73              0.043       Maclaine Pont et al. 1980
                                    1       8% dust2     8 kg/ha         70-73              0.033
                                            8% dust2     9.6 kg/ha4      78                 <0.013

    Watermelon     Taiwan Province
    peel           of China
                   1982             1       25% E.C.     3 x 4.17 g/hl   0-1                0.013       Wang 1982
                                                                         3                  <0.013
                                                                         5-6                <0.013
                                                                         9                  <0.013
                                                                         12                 <0.013
                                                                         0-1                <0.013
                                                                         3                  <0.013
                                                                         5-6                <0.013
                                                                         9                  <0.013
                                                                         12                 <0.013
                                                                                                                                      

    Table 2 (continued)

                                                                                                                                      

                   Country/         No. of  Formulation  Application     Interval after     Residues,   Reference
    Crop           Year             trials               rate (a.i.)     final application  (mg/kg)1
                                                                         (days)
                                                                                                                                      

    Watermelon     Taiwan Province                       3 x 6.25        0-1                0.023
    peel           of China                                              3                  <0.013
                                                                         5-6                <0.013
                                                                         9                  <0.013
    flesh                                                                12                 <0.013
                                                                         0-1                <0.013
                                                                         3                  <0.013
                                                                         5-6                <0.013
                                                                         9                  <0.013
                                                                         12                 <0.013

    Apple          The Netherlands  2       50% W.P.5    2 x 25 g/hl     63                 <0.013      Maclaine Pont et al. 1980
                   1978                                                  84                 <0.013

                   United Kingdom   2       25% W.P.     7 x 60 g/hl     0-1                0.473       Hayto 1976
                   1977                                                  14-16              0.083
                                                                         30-31              0.023
                                            25% E.C.     8 x 51.48 g/hl  0-1                4.183       Hayto 1977c
                                                                         8                  1.763
                                                                         18-19              0.683
                                                                         30-31              0.173
                                                                         50                 0.023

                   Taiwan Province  1       25% E.C.     9 x 8.33 g/hl   0-1                0.243       Wang 1982
                   of China                                              3                  0.123
                   1982                                                  5-6                0.073
                                                                         12                 0.013
                                                                         14-16              0.053
                                                                         18-19              0.023
                                                                                                                                      

    Table 2 (continued)

                                                                                                                                      

                   Country/         No. of  Formulation  Application     Interval after     Residues,   Reference
    Crop           Year             trials               rate (a.i.)     final application  (mg/kg)1
                                                                         (days)
                                                                                                                                      

    Apple          Taiwan Province                       9 x 16.67 g/hl  0-1                0.813
                   of China                                              3                  0.373
                                                                         5-6                0.203
                                                                         12                 <0.013
                                                                         14-16              0.083
                                                                         18-19              0.073

    Pear           The Netherlands  1       50% W.P.5    1 x 0.1 kg/hl   21-25              0.033       Maclaine Pont et al. 1980
                   1978                                  1 x 0.2 kg/hl   21-25              0.063
                                                         2 x 0.1 kg/hl   14-16              0.263
                                                         2 x 0.2 kg/hl   14-16              0.243

    Apricots       Israel           1       50% W.P.5    1 x 60 g/hl     89                 <0.05       Snowden 1983
                   1982

    Cherries       France           1       50% W.P.5    1 x 10 g/hl     70-73              <0.05
                   1982                                  1 x 20 g/hl     70-73              <0.05
                                                         4 x 20 g/hl     21-25              0.45

    Nectarines     France           1       50% W.P.5    5 x 20 g/hl     14-16              0.56
                   1982

    Peaches        South Africa     1       50% W.P.5    3 x 10 g/hl     132                <0.05
                   1982             1                    3 x 20 g/hl     132                <0.05
                                    1                    8 x 10 g/hl     30-31              0.21

    Plums          Italy            1       40% E.C.     1 x 30 g/hl     102                <0.05
                   1982             1                    2 x 30 g/hl     77                 <0.05
                                    1                    3 x 30 g/hl     50                 0.82

                                                                                                                                      

    Table 2 (continued)

                                                                                                                                      

                   Country/         No. of  Formulation  Application     Interval after     Residues,   Reference
    Crop           Year             trials               rate (a.i.)     final application  (mg/kg)1
                                                                         (days)
                                                                                                                                      

    Plums          South Africa     1       50% W.P.5    1 x 30 g/hl     50                 0.21
                   1981             1                    1 x 40 g/hl     50                 0.28
                                    1                    2 x 30 g/hl     14-16              0.97
                                    1                    2 x 40 g/hl     14-16              0.60
                   1982             1       50% W.P.5    3 x 10 g/hl     104                <0.05
                                                         3 x 20 g/hl     104                <0.05
                                                         6 x 10 g/hl     5-6                0.12
                                                         4 x 10 g/hl     103                <0.05
                                                         4 x 20 g/hl     103                <0.05
                                                         7 x 10 g/hl     5-6                0.19

    Grapes         Taiwan Province  1       25% E.C.     2 x 4.17 g/hl   3                  0.393       Wang 1982
                   of China                                              5-6                0.193
                   1982                                                  8                  0.203
                                                                         9                  0.103
                                                                         12                 0.073
                                                                         21-25              0.103
                                                                         39                 0.053
                                                                         42-46              <0.013
                                    1       25% E.C.     2 x 6.25 g/hl   3                  0.493
                                                                         5-6                0.263
                                                                         8                  0.203
                                                                         9                  0.253
                                                                         12                 0.133
                                                                         21-25              0.133
                                                                         39                 0.053
                                                                         42-46              <0.013
                                                                                                                                      

    Table 2 (continued)

                                                                                                                                      

                   Country/         No. of  Formulation  Application     Interval after     Residues,   Reference
    Crop           Year             trials               rate (a.i.)     final application  (mg/kg)1
                                                                         (days)
                                                                                                                                      

    Grapes         Taiwan Province  1       25% E.C.     7 x 10 g/hl     3                  0.203
                   of China                                              5-6                0.133
                                                                         8                  0.293
                                                                         9                  0.273
                                                                         12                 0.143
                                                                         21-25              0.223
                                                                         39                 0.083
                                                                         42-46              0.083
                                    1       25% E.C.     7 x 16.67 g/hl  3                  0.423
                                                                         5-6                0.203
                                                                         8                  0.163
                                                                         9                  0.603
                                                                         12                 0.673
                                                                         21-25              0.343
                                                                         39                 0.183
                                                                         42-46              0.103

    Strawberries   The Netherlands  1       50% W.P.5    2 x 0.1 kg/hl   30-31              0.173       Maclaine Pont et al. 1980
                   1978             1                    2 x 0.15 kg/hl  30-31              0.173

    Almonds        Israel
    shell          1982             1       50% W.P.5    2 x 0.1 kg/hl                      0.616       Churchill & Longland 1983d
    kernel                                                                                  0.106
    whole nut                                                                               0.296
                                                                                                                                      

    Table 2 (continued)

    1    Total residues of prochloraz and major metabolites unless otherwise stated. Total residue measured as 2,4,6-trichlorophenol (BTS 45186)
         and converted to prochloraz-derived residues by correcting for the molecular weight factor (1.906).

    2    Co-formulation with dicloran.

    3    Prochloraz residues only.

    4    Preplanting application.

    5    Prochloraz-manganese complex 50% wettable powder formulation.

    6    Applications made at blossom and 20 days later. Preharvest interval estimated at about 2.5 to 3 months.

    Table 3.  Supervised Residue Trials With Prochloraz on Citrus Fruits - Post-Harvest Applications

                                                                                                                                            

                                                                                             Residues (mg/kg)1
                                                                                                                             
                                                          Application
    Country/           Crop       No. of   Formulation    rate (a.i.)              Peel           Flesh          Whole Fruit3   Reference
    Year                          Trials                  and method
                                                                                                                                            

    Australia          Oranges    1        40% E.C.       25g/hl dip3              1.40-3.4       <0.05          n.d.           Browne 1981a
    1981                                                                           (1.45-3.954)   (0.3-0.104)

                                  1        40% E.C.       50g/hl dip3              1.58-3.36      <0.05          n.d.
                                                                                   (2.25-3.354)   (<0.02-0.054)

    Italy              Oranges    1        25% W.P.       50g/hl dip5              1.59-1.72      0.04-0.05      0.71-0.80      Browne & Manley
    1981                          1        25% E.C.       50g/hl dip5              4.57-6.40      0.09-0.16      1.80-2.35      1982b
                       Lemons     1        25% W.P.       50g/hl dip5              3.61-4.04      0.08-0.14      1.58-1.83
                                  1        25% E.C.       50g/hl dip               5.67-6.95      0.08-0.19      2.36-2.97

    South              Oranges    1        40% E.C.       100g/hl wax              1.38-2.79      0.03-0.08      0.38-0.72      Manley & Snowden
    Africa                                                brush6                                                 (0.34-0.478)   1982b
    1982                          1        40% E.C.       200g/hl wax              2.45-3.74      0.02-0.07      0.65-0.94
                                                          brush6                                                 (0.91-1.198)
                                  1        40% E.C.       200g/hl wax              n.d.           n.d.           1.36-1.698)
                                                          brush7
                       Oranges    1        45% E.C.       50g/hl brush9            0.34           <0.05          0.08           Snowden & Manley
                                                                                                                 (0.108)        1983
                                  1        45% E.C.       100g/hl brush9           0.47           <0.05          0.13
                                                                                                                 (0.16-0.178)
                                  1        45% E.C.       200g/hl brush9           1.84           <0.05          0.39
                                                                                                                 (0.39-0.438)
                                  1        45% E.C.       400g/hl brush9           3.07           0.07           0.63
                                                                                                                 (0.70-0.758)

                                                                                                                                             

    Table 3 (continued)

                                                                                                                                             

                                                                                             Residues (mg/kg)1
                                                                                                                             
                                                          Application
    Country/           Crop       No. of   Formulation    rate (a.i.)              Peel           Flesh          Whole Fruit3   Reference
    Year                          Trials                  and method
                                                                                                                                             

    Spain              Oranges    1        25% E.C.       50g/hl dip10             1.48-3.224     0.04-0.10      0.67-1.4511    Kelly 1982d
    1979                          1        25% E.C.       100g/hl dip10            1.40-4.084     0.04-0.11      0.67-1.8011

    1980               Oranges    1        40% E.C.       300g/hl wax              3.3-4.74       0.32-0.38      n.d.           Richards 1980b
                                                          spray12
                                  1        40% E.C.       300g/hl wax              n.d.           0.005-0.00813  n.d.           Richards 1980e
                                                          spray12
                                  1        40% E.C.       200g/hl wax              1.2-6.7        0.04-0.44      n.d.           Richards 1980f
                                                          spray12
                                  1        40% E.C.       250g/hl wax              3.7-7.9        0.04-0.30      n.d.
                                                          spray12
                                  1        40% E.C.       300g/hl wax              5.4-6.4        0.06-0.13      n.d.
                                                          spray12

    1981               Oranges    1        40% E.C.       300g/hl shower14         4.7-8.4        0.11-0.39      1.50-2.47      Browne 1981b
                                                                                   (1.7-7.34)     (0.12-0.394)   (0.64-2.434)

    1981               Lemons     1        40% E.C.       300g/hl                  11.0-17.9      0.17-0.33      3.66-6.13      Browne 1982c
                                                          shower15                 (9.1-15.64)    (0.27-0.304)   (3.14-5.554)

    United             Oranges    1        40% E.C.       70g/hl dip16             5.78-7.81      0.07-0.15      1.37-2.07      Browne 1982i
    Kingdom                                                                        (3.55-5.104)   (0.05-0.124)   (0.96-1.354)
    1981
                                                                                                                                            

    Table 3 (continued)

    n.d. - not determined.
    1    Total residues of prochloraz and major metabolites unless otherwise stated (see notes 4 and 13). Total residue measured as 
         2,4,6-trichlorophenol (BTS 45186) and converted to prochloraz-derived residue by correcting for the molecular weight factor (x 1.906).
    2    Residue levels in whole fruit calculated from separate peel and flesh residues unless otherwise stated (see note 8).
    3    Residue levels obtained from five sampling intervals at 1,2,4,8 and 16 days storage at ambient temperature after treatment.
    4    Determination of free prochloraz levels only.
    5    Fruit was stored for 57 days at 7C after treatment.
    6    Residue levels obtained from four sampling intervals under two storage conditions. Treated fruit was sent to the United Kingdom under 
         normal commercial refrigerated shipment and then stored at either 20 or 4C, 44 days later. Samples of fruit from each storage 
         condition were then taken at 0,7,14 and 21-day intervals.
    7    Prochloraz applied in mixture with 2,4,-0 and thiabendazole. Storage conditions as in Note 6 except sampled after 44 days refrigerated
         shipment and 21 days storage under ambient or cool conditions.
    8    Residue analysis of whole fruit.
    9    Fruit was treated in July 1982, sent to the United Kingdom under normal refrigerated shipment and stored at ambient temperature until
         September 1982.
    10   Residue levels following storage of fruit for either 10 days at 20-22C or 60 days at 3-4C after treatment.
    11   Residue level calculated from determination of free prochloraz residue in peel and total prochloraz plus major metabolites in flesh.
    12   Residue levels following storage of fruit for either 7 or 14 days at ambient temperature after treatment.
    13   Determination of free 2,4,6-trichlorophenol (BTS 45186) only, expressed as 2,4,6-trichlorophenol.
    14   Residue levels following storage of fruit for either 14, 20 or 27 days at ambient temperature after treatment.
    15   Residue levels following storage of fruit for either 12 or 16 days at ambient temperature after treatment.
    16   Residue levels following storage of fruit for either 1,7, 21, 35 or 70 days in cold storage after treatment.
    
    Strawberries

         No information was provided on good agricultural practices for
    prochloraz on strawberries. Limited residue data from the use of the
    manganese complex W.P. formulation were provided (Table 2) with
    residues of 0.2 mg/kg prochloraz found 16 days after treatment.
    Recoveries were reported as >80 percent and sensitivity as 
    0.001-0.005 mg/kg.

    Fruit with Inedible Peel

         No information on good agricultural practice was available for
    the use of prochloraz on fruit with inedible peel. Residue data
    resulting from either foliar (Table 4) and/or postharvest applications
    (Table 5) were available for several of these crops. The "recommended"
    application rates were provided for most of them but no preharvest
    intervals were specified.

    Avocados

         No information on good agricultural practice was provided for
    avocados. Residue data at normal harvest and "recommended" application
    rates were available for both foliar and postharvest treatments. At 2X
    the 10-25 g a.i./hl "recommended" foliar W.P. (manganese complex)
    application rate, maximum total residues on whole fruit basis were 2.5
    mg/kg seven days after treatment, with approximately 10 percent of the
    residue in the flesh (Table 4). No preharvest interval was given.
    However, these data are questionable because of conflicting peel
    residue levels in the data submission. Data were also available from
    multiple applications of an E.C. formulation at 25-50 g a.i./hl,
    although not even "recommended" uses were available for this
    formulation. In these trials residues continually declined from 14 to
    63 days after treatment, with estimated half-lives ranging from 40-98
    days (mean 75.4 days). At these longer intervals residues in flesh
    account for 20-30 percent of the whole fruit residue. The limit of
    determination was said to be 0.15 mg/kg, although control values were
    as high as 0.12, 0.16 and 0.39 mg/kg in flesh, peel and whole fruit,
    respectively.

         For postharvest treatments of avocados 25-50 g a.i./hl
    (formulation unspecified) is "recommended", although no good
    agricultural practice information was available. Ten trials reflecting
    the "recommended" application rates were conducted in one country with
    dip or spray E.C. applications (Table 5). Total residues ranged from
    0.3 to 3.5 mg/kg on a whole fruit basis, with little difference in
    values between stored at 23 for eight days or fruit frozen
    immediately. Little difference was reported between 1X and 2X
    recommended application rates. These residues levels are generally
    comparable to those found from multiple foliar treatments. The limited
    data indicate residues in the flesh at levels up to 30 percent of
    those in whole fruit, even at relatively short intervals after
    treatment.


        Table 4   Prochloraz Residues in Fruit Following Supervised Trials - Foliar Application

                                                                                                                                             

    Country/    Crop      No. of
    Year                  trials  Formulation  Application   Interval after     Mean residue level (mg/kg)1            Reference
                                               rate (a.i.)   final application                                      
                                                              (days)            Peel       Flesh       Whole fruit2
                                                                                                                                             

    Australia   Avocado   1       50% W.P.     7x15g/tree3   7                  8.1-13.6   0.09-0.28   1.70-2.51       Cron & Longland 1983a
    1981/2                                     (49.5 g/hl)                      (11)7      (0.16)      (2.1)

    South       Avocado   1       45% E.C.     2x25g/hl4     14                 1.52       <0.10       0.44            Churchill &
    Africa                                                   48                 1.19       <0.10       0.36            Longland 1983b
    1982                                                     63                 1.01       <0.10       0.30

                          1       45% E.C.     2x37.5g/hl4   14                 1.85       0.12        0.61
                                                             48                 1.45       <0.10       0.25
                                                             63                 0.84       <0.10       0.25

                          1       45% E.C.     2x50g/hl4     14                 2.63       0.17        0.83
                                                             48                 1.94       0.18        0.59
                                                             63                 2.16       0.14        0.60

    Australia   Mango     1       50% W.P.     6x100g/hl5    77                 0.15-0.30  0.01-0.02   0.05-0.096      Browne & Manley 1982c
    1981                                                                        (0.22)8    (0.01)8     (0.07)8

    Israel      Mango     2       50% W.P.     3x50g/hl      15                 3.39-4.87  0.03-0.07   0.77-0.956      Longland &
    1982                                                                        (4.2)8                                 Churchill 1983
                                                                                                                                             

    Table 4 (continued)

    1    Total residues of prochloraz and major metabolites, measured as 2,4,6-trichlorophenol (BTS 45186) and converted to 
         prochloraz-derived residue by correcting for the molecular weight factor (x1.906).

    2    Residue in whole fruit (without stone) calculated from separate peel and flesh residues.

    3    Applications made at approximately monthly intervals from fruit set to fruit full size.

    4    Applications made with a seven-week interval between treatments.

    5    Applications made from beginning of flowering to Pethenoccupic fruit drop.

    6    Residue level in whole fruit including stone (calculated from peel/flesh residues).

    7    Mean in parentheses.

    8    Four samples.

    Table 5   Prochloraz Residues in Fruit Following Supervised Trials - Postharvest Application

                                                                                                                                           

                                                                           Mean residue level (mg/kg)1
    Country/       Crop       No. of    Formulation    Application rate                                             
    Year                      trials                   (a.i.)              Peel          Flesh         Whole fruit2      Reference
                                                                                                                                           

    Australia      Avocado    1         40% E.C.       25 g/hl dip4        n.d.          n.d.          0.88-1.313        Browne 1982a
    1981                      1         40% E.C.       50 g/hl dip4        n.d.          n.d.          1.14-1.353
    1982                      2         45% E.C.       25 g/hl dip4        3.28-5.35     <0.10-0.12    0:30-0.557        Churchill &
                              2         45% E.C.       25 g/hi dip6        n.d.          n.d.          0.16-1.019        Longland 1983e
                              1         45% E.C.       50 g/hl spray4      2.33-3.90     <0.10-0.11    0.28-0.367
                              1         45% E.C.       50 g/hl spray6      n.d.          n.d.          0.34-0.429
    1983                      1         45% E.C.       25 g/hl dip6        n.d.          n.d.          2.369
                              1         45% E.C.       50 g/hl dip6        n.d.          n.d.          3.499
    1981           Banana     1         40% E.C.       25 g/hl dip5        6.06-7.88     0.02-0.04     n.d.              Browne 1982b
                              1         40% E.C.       50 g/hl dip5        5.18-9.97     0.03-0.05     n.d.

    South          Banana     2         45% E.C.       25 g/hl dip8        6.5-9.1       0.10-0.20     2.78-3.94         Churchill &
    Africa                    2         45% E.C.       50 g/hl dip8        9.8-16.6      0.14-0.23     4.02-6.75         Longland 1983a
    1982

    Israel         Mango      1         40% E.C.       40 g/hl dip         6.10-8.32     0.02          1.277             Longland &
    1982                                                                                                                 Churchill 1983

    Australia      Papaya     1         45% E.C.       25 g/hl dip6        2.13-3.42     0.01-0.18     0.50              Cron & Longland 1983b
    1982                      1         45% E.C.       50 g/hl dip6        3.86-4.12     0.09-0.15     0.80
                                                                                                                                           

    Table 5 (continued) 

    n.d. - not determined.

    1    Total residues of prochloraz and major metabolites, measured as 2,4,6-trichlorophenol (BTS 45186) and converted to prochloraz-derived 
         residue by correcting for the molecular weight factor (x 1.906).

    2    Residue in whole fruit calculated from separate peel and flesh residues unless otherwise stated (see notes 3 and 9).

    3    Residue analysis of whole fruit (excluding stone).

    4    Fruit stored for 7-8 days at 23C after treatment.

    5    Mean residue levels following storage of fruit for either 9,10,12 or 16 days at ambient temperature after treatment.

    6    Fruit frozen within one to four hours after treatment.

    7    Calculated whole fruit residue including weight of stone.

    8    Fruit stored for 7 days at 8C after treatment.

    9    Residue analysis of whole fruit (including stone).
    
    Bananas

         No information was provided on goad agricultural practices for
    the use of prochloraz on bananas. "Recommended" application rates for
    foliar application are 10-25 g a.i./hl WP (manganese complex) for
    foliar high volume applications (100-200 g a.i./ha low volume) and 
    25-50 g a.i./hl for postharvest treatment (formulation not specified).

         No trials data were available for foliar applications, but trials
    were reported from two countries for postharvest dips that reflected
    "recommended" application rates (Table 5). Total prochloraz and
    metabolite residues on a whole product basis ranged from 2.8-6.8 mg/kg
    when fruit was stored for seven days at 8C, with less than 2 percent
    of the total fruit residue found in the flesh. No significant change
    in residues were observed over the storage intervals of 7 to 16 days
    or between 8C and ambient temperatures. No significant difference
    between residues resulted from the two application rates.

         Analytical recoveries were generally 85  15 percent. The limit
    of determination was estimated at 0.05-0.1 mg/kg, although apparent
    residues in untreated controls were as much as 0.32 mg/kg in the skin
    and <0.2 mg/kg in whole fruit.

    Mangoes

         No information on good agricultural practice was available for
    the use of prochloraz on mangoes. A 50 percent W.P. manganese complex
    is "recommended" for foliar treatments at 10-25 g a.i./hl and at 25-50
    g a.i./hl for postharvest treatment, although no formulation is
    specified for the latter. One trial for foliar application was
    conducted in each of two countries with multiple applications at 2X to
    4X the "recommended" foliar rate (Table 4). Maximum total residues on
    a whole fruit basis were 0.09 mg/kg from the higher application rate
    77 days after treatment and up to 1 mg/kg 15 days after application at
    the lower rate. In both cases, most of the residue was in the peel,
    although flesh residues appeared to increase with time, being
    approximately 3 percent of total fruit residue after 15 days to over
    10 percent after 77 days (based on peel: flesh:seed ratios from the
    77-day study).

         One trial was conducted in one country for postharvest treatment
    which reflected the "recommended" application rate. At 1.27 mg/kg on a
    whole fruit basis, residues were similar to those of the 15-day
    preharvest trial, although residues in flesh were only approximately 
    1 percent of the total for the postharvest treatment. Over-all
    analytical recoveries for mangoes were generally 80 percent or better
    and apparent residues in untreated controls were <0.02 mg/kg on a
    whole fruit basis and up to 0.1 mg/kg on peel. The limit of
    determination was estimated at 0.1 mg/kg.

    Papaya

         No information was available on good agricultural practices for
    prochloraz on papaya. A 50 percent W.P. manganese complex is
    "recommended" for foliar treatment at 10-25 g a.i./hl and 25-50 g
    a.i./hl (formulation not specified) is "recommended" for postharvest
    treatments. No preharvest intervals were given.

         No residue information was available from foliar treatments, but
    two postharvest dip trials with an E.C. formulation were conducted in
    one country and reflected the "recommended" application rates (Table
    5). Samples were frozen one hour after the dip treatment for analysis
    45 days later. On a whole fruit basis, residues of prochloraz and
    metabolites (corrected for approximately 80 percent recoveries) were
    0.5 and 0.8 mg/kg for the two application rates. Approximately 15
    percent of the whole fruit residue was in flesh. Apparent residue in
    the untreated control was 0.023 mg/kg on a whole fruit basis. The
    limit of determination was estimated as 0.1 mg/kg in flesh and peel.

    Cereal Grains

         Over 270 residue trials were conducted in 10 European and one
    Asian country, which included foliar or seed treatments with six
    different E.C. formulations alone or in combination with other
    chemicals. Results are reported mostly as total residues of prochloraz
    and metabolites, determined as the trichlorophenol but expressed as
    prochloraz (Tables 6-9). Some are for residues of prochloraz only.
    Good agricultural practice information was available for eight
    countries.

    Wheat

         Over 100 field trials were conducted in nine countries,
    representing 270 samples from a variety of formulations and treatment
    conditions. Some trials reflected known good agricultural practices
    and good agricultural practices could not be determined for others.
    Over-all residues of prochloraz and major metabolites in mature grain
    from foliar treatment ranged from 0.01-0.3 mg/kg and in straw at
    harvest 0.08-16 mg/kg, although most grain residues were <0.1 mg/kg
    (Table 6). The high grain value is from a 38-day preharvest interval
    in a country whose good agricultural practices are not known, although
    the application rate and preharvest interval were compatible with good
    agricultural practices in other countries. Apparent residues in
    untreated controls were generally <0.02 mg/kg in grain and <0.3
    mg/kg in straw, but were occasionally higher in the latter. Residues
    of prochloraz alone were lower and ranged from <0.01 to 0.03 mg/kg in
    mature grain and <0.01 to 0.19 mg/kg in straw.


        Table 6.  Supervised Residue Trials with Prochloraz on Wheat at Harvest

                                                                                                                                             

    Country/     Formulation    No. of    Application rate2  No. of      Interval after         Residue (mg/kg)1          Reference
    Year                        trials    (kg a.i./ha)       samples     final application                            
                                                                         (days)               grain         straw
                                                                                                                                             

    Austria      25% E.C.       2         0.5                2           70-78                <0.013        0.013           Kelly 1979a
    1977                        2         1.0                2           70-78                <0.01-0.013   <0.013

    1978         22.5% E.C.     1         0.45               4           94                   <0.02-0.02    3.66-8.39       Kelly 1979f
                                1         0.9                4           94                   0.02-0.04     11.63-12.20

    Belgium      45% E.C.       1         0.45               2           (0)5                 0.02          n.d.            Housden 1982a
    1981                        1         0.454              2           (0)5                 0.01          n.d.

    Denmark      25% E.C.       3         0.625              6           95-98                <0.02-0.02    n.d.            Kelly 1979g
    1979
                 40% E.C.       1         0.6                2           77                   <0.02         2.1-2.5         Richards 1980d

    1982         45% E.C.       1         0.45               1           56                   0.106         2.01            Housden 1982c
                                2         2 x 0.23(19)7      2           75-85                <0.02         1.47-1.94
                                2         0.23 x 0.45(19)7   2           75-85                <0.02         1.87-2.36
                                2         2 x 0.45(19)       2           75-85                <0.02-0.02    1.56-2.07
                                2         2 x 0.45(19)7      2           75-85                <0.02         1.72-2.79

    Finland      45% E.C.       2         0.45               2           28-50                <0.02         n.d.            Heinanen 1983
    1982

    France       25% E.C.       2         0.5                6           105                  <0.01-0.023   <0.01-0.023     Hayto 1978b
    1977                        2         1.0                6           105                  <0.01-0.013   <0.01-0.183
                                2         2 x 0.5(38-46)     6           67-69                <0.01-0.033   0.01-0.123
                                2         2 x 1.0(38-46)     6           67-69                <0.01-0.013   0.01-0.0733

                                1         0.5                3           105                  <0.0058       n.d.            Kelly 1980b
                                1         1.0                3           105                  <0.0058       n.d.
                                1         2 x 0.5(38)        3           67                   <0.0058       n.d.
                                1         2 x 1.0(38)        3           67                   0.008-0.0158  n.d.
                                                                                                                                             

    Table 6 (continued)

                                                                                                                                             

    Country/     Formulation    No. of    Application rate2    No. of     Interval after       Residue (mg/kg)1             Reference
    Year                        trials    (kg a.i./ha)         samples    final application                            
                                                                          (days)               grain         straw
                                                                                                                                             

    1978         25% E.C.       3         0.45                   18       55-113               <0.02-0.06    0.50-9.66      Kelly 1979h
                                3         0.75                   18       55-113               <0.02-0.11    0.88-9.91

    1979         40% E.C.       1         0.45                   3        80                   <0.02         2.42-3.22      Richards 1980a
                                3         2 x 0.45(23-28)        9        72-77                0.04-0.10     2.40-16.3
                                1         2 x 0.45(8)9           3        77                   0.04-0.08     3.93-4.80

                 30% E.C.10     1         0.45                   3        80                   <0.02         2.23-2.55
                                3         2 x 0.45(22)           9        61-81                <0.02-0.08    2.29-6.16

    Federal      25% E.C.       3         0.5                    4        81-107               <0.01-0.013   0.01-0.023     Hayto 1979c
    Republic of                 2         0.75                   3        81                   <0.013        0.01-0.023
    Germany                     1         1.0                    1        107                  <0.013        <0.013
    1977

    1978         25% E.C.       2         0.5                    4        56-61                0.06-0.08     3.6-12.0       Kelly 1979c

    1979         40% E.C.       3         2 x 0.48(21-30)        3        54-63                <0.02-0.06    1.0-5.9        Richards 1980g

    1980         40% E.C.       3         2 x 0.48(17-23)        3        59-66                0.01-0.04     0.7-2.0        Reary 1981b
                                3         3 x 0.48(11-23/7-13)   3        59-66                0.03-0.06     1.1-3.6

    1981         40% E.C.       5         3 x 0.48(11-29/8-19)   10       57-64                0.02-0.13     1.07-6.40      Browne 1982e
                                2         2 x 0.48(28-30)        3        43-60                0.06          1.88-3.59      Browne 1982f
                                3         3 x 0.48(9-22/8-19)    7        43-66                0.05-0.08     4.05-4.55
                                1         3 x 0.48(17/6)         1        55                   0.05          0.4811

    1982         30% E.C.10     1         0.45                   3        85                   <0.05         0.08-0.27      Housden &
                                                                                                                            Longland 1983

                                                                                                                                             

    Table 6 (continued)

                                                                                                                                             

    Country/     Formulation    No. of    Application rate2      No. of   Interval after         Residue (mg/kg)1           Reference
    Year                        trials    (kg a.i./ha)           samples  final application                            
                                                                          (days)               grain         straw
                                                                                                                                             

    Italy        25% E.C.       2         0.07                   6        55                   <0.01-0.013   0.02-0.093     Hayto 1977b
    1977                        3         1.0                    9        39-55                <0.01-0.013   0.02-0.193,12

    1978         25% E.C.       1         0.5                    2        38                   0.08-0.17     4.82-15.76     Kelly 1979d
                                1         0.7                    38       0.13-0.29            6.29-14.73

    The          25% W.P.       1         0.375                  3        71                   <0.013        <0.013         Hayto 1978a
    Netherlands  25% E.C.       1         0.375                  3        73                   0.01-0.023    <0.01-0.013
    1977                        1         0.5                    3        73                   0.01-0.023    0.01-0.023

    1978         25% E.C.       1         0.375                  3        68                   0.04          1.14-1.51      Kelly 1979e
                                1         0.75                   3        68                   0.04-0.06     5.66-8.14

    1979         40% E.C.       1         0.5                    4        71                   <0.02         0.88-2.23      Kelly 1980c

    1980         45% E.C.       2         0.45                   6        69                   0.01-0.02     0.41-0.77      Reary 1981c
                                1         0.675                  2        106                  0.01          0.21-0.51
                                1         2 x 0.45 (15)          3        69                   0.01-0.02     2.21-3.29

    Sweden       45% E.C.       8         0.45                   8        67-91                <0.02         0.08-4.08      Longland 1983a
    1982                        2         2 x 0.45(15-29)        2        58-69                0.03-0.07     1.29-6.34

    United       25% E.C.       2         0.4                    6        90-115               <0.013        <0.013          Hayto 1977a
    Kingdom                     2         1.0                    6        90-115               <0.013        <0.013
    1976

    1977         25% E.C.       4         0.5                    12       124-126              <0.013        <0.013         Hayto 1979a

    1979         40% E.C        2         2 x 0.4(36-37)         6        69-79                <0.02-0.06    4.2-11.2       Richards 1980c
                 10% S.D.13     1         0.214                  2        31015                <0.02         <0.02
                                                                                                                                             

    Table 6 (continued)

    n.d.- not determined.
    1/ Total residues of prochloraz and major metabolites, unless otherwise stated (see Notes 3 and 8). Total residue as 2,4,6-trichlorophenol
       (BTS 45186) and converted to prochloraz-derived residue by correcting for the molecular weight factor (x 1.906).
    2/ Figures in parentheses indicate interval in days between applications.
    3/ Determination of free prochloraz residues only.
    4/ Prochloraz applied in mixture with carbendazim.
    5/ Growth stage at application : 0 - heading.
    6/ Residue analysis of whole ears.
    7/ Prochloraz applied in mixture with fenpropimorph. 
    8/ Determination of free 2,4,6-trichlorophenol (BTS 45186) residues only, expressed as BTS 45186.
    9/ Prochloraz applied in mixture with mancozeb.
    10/ Co-formulation of prochloraz with carbendazim.
    11/ Mean residue level in whole ears. A mean residue level of 2.31 mg/kg was found in the whole plant.
    12/ Results from two trials.
    13/ Seed dressing co-formulation with carboxin.
    14/ Rate of application in g a.i./kg seed.
    15/ Days after sowing treated seed.
    
    Barley

         Information on good agricultural practice for barley was
    available from five countries and residue trials reflecting such uses
    were reported from those countries and others (Table 7). At-harvest
    residues of prochloraz and its major metabolites, from foliar
    applications, ranged from <0.01-0.68 mg/kg in mature grain and 
    <0.01-15 mg/kg in straw (Table 7). Again, the higher values are
    generally from the shorter preharvest intervals, which reflect good
    agricultural practice, and from trials in which prochloraz was 
    co-applied with either carbendazim or mancozeb. The rates reflect
    usage in the country where the trials were conducted. Most residues in
    grain were <0.2 mg/kg. Although grain residues from these shorter
    intervals were significantly higher than those from longer intervals,
    residues in straw were not.

         Analytical recoveries were variable, with means ranging from 
    70-100 percent. Apparent residues in untreated controls were <0.02
    mg/kg in grain and up to 0.2 mg/kg in straw. Residues of prochloraz
    alone were substantially lower, ranging from <0.01-0.02 mg/kg in
    mature grain and <0.01-0.15 mg/kg in straw, which are comparable to
    the values reported in wheat.

    Rye

         Total prochloraz and its metabolites, from foliar treatments in
    mature rye grain or whole ears ranged from <0.02-0.1 mg/kg and in
    straw from 0.4-2.5 mg/kg. Application rates reflected good
    agricultural practice, although the preharvest interval of 72 to 109
    days was significantly greater than the one month permitted (Table 8).
    Analytical recoveries were typically >80 percent in grain and
    somewhat lower in straw. Apparent residues in untreated controls were
    <0.01 mg/kg in grain but as high as 0.04 mg/kg in straw.

    Oats

         Information on good agricultural practice for oats was not
    available for the country in which residue trials were conducted or
    from other countries. Residues of prochloraz and its metabolites were
    <0.03 mg/kg and <1.6 mg/kg for whole ears and straw, respectively,
    62 days after treatment at application rates considered good
    agricultural practice for other cereals (Table 8).

    Rice

         No information on good agricultural practice was available for
    rice, except for seed treatments in one country (for which there are
    no data). Residues of prochloraz alone in unpolished brown rice 7-21
    days after treatment at application rates comparable to good
    agricultural practice on other cereals were <0.05 mg/kg (Table 8).
    Residues of prochloraz and its metabolites would be expected to be
    higher. Residues from seed treatments were lower, but the interval

    after treatment was 151-168 days. Analytical recoveries were 86
    percent in grain and apparent residues in untreated controls were
    <0.005 mg/kg, the limit of detection.

         Summary data for residues in cereal grain at harvest (Table 9)
    represents foliar applications of all formulations. The data in Table
    9 confirm those reported in Tables 6-8, since it is statistically
    shown that maximum residues of prochloraz and its metabolites would
    normally be less than 0.2 mg/kg at the longer preharvest intervals but
    residues up to 0.4 mg/kg can occur. Other trials at shorter intervals
    also resulted in higher grain residues than at longer intervals.
    Similarly, Table 11 confirms the findings reported in Tables 6-8 for
    residues in straw (up to 15 mg/kg). Tables 9 and 11 do not include
    more recent studies (Housden 1982c; Longland 1983a; Housden & Longland
    1983; Heinanen 1983) reported in Tables 6-8, but these would not
    increase expected residues. Tables 9 and 11 also indicate that higher
    residues can be expected from multiple or higher doses.

         Residues of prochloraz alone were <0.03 mg/kg in cereal grains
    at harvest, except for rice where residues were as much as 0.05 mg/kg 
    7 to 21 days after treatment. From seed treatment alone, residues of
    prochloraz and its metabolites in mature grain were <0.02 mg/kg.
    Generally, there was no conclusive evidence of increased residues as a
    result of co-application of prochloraz and other agricultural
    chemicals.

         Residue decline studies are summarized in Table 10. Half-lives of
    approximately 6 to 17 days could be estimated for ears or whole plants
    of wheat or barley on the basis of sampling for at least three
    successive intervals. Residues of prochloraz and its metabolites
    ranged from 0.15 to 21 mg/kg on green plants or ears on the day of
    last treatment to 0.07-3.6 mg/kg at 21 to 48 days, which approximates
    typical preharvest intervals.

    Almonds

         No information was available on good agricultural practice for
    prochloraz on almonds. Foliar treatments with the 50 percent W.P.
    manganese complex are "recommended" at 15-30 g a.i./hl. No preharvest
    interval has been reported. One trial was conducted with foliar
    treatments at seven times the maximum recommended application rate
    (Table 2) with total residues corrected for recoveries of >86
    percent of 0.61, 0.1 and 0.29 mg/kg in shell, kernel and whole nut
    (calculated from shell and kernel residues), respectively, about three
    months after the last treatment. Apparent residues were 0.06 mg/kg in 
    un-treated controls on a whole nut basis and up to 0.09 mg/kg in the
    shell. The limit of determination was estimated at 0.1 mg/kg.


        Table 7   Supervised Residue Trials with Prochloraz on Barley at Harvest

                                                                                                                                           

    Country/     Formulation    No. of    Application rate2      No. of   Interval after          Residue (mg/kg)1          Reference
    Year                        trials    (kg a.i./ha)           samples  final application                            
                                                                          (days)               grain         straw
                                                                                                                                           

    Austria      25% E.C.       2         0.5                    2        61-73                <0.013        <0.01-0.02
    1977                        1         0.75                   1        73                   <0.013        0.023
                                1         1.0                    1        61                   <0.013        0.033
                                1         2x0.5(19)              2        54                   <0.013        <0.013

    1978         22.5% E.C.     2         0.45                            69-75                <0.02-0.04    0.65-1.30      Kelly 1979f
                                1         0.9                             75                   0.02-0.04     1.0-2.1

    Belgium      45% E.C.       3         0.45                   6        (M)10                0.01-0.03     n.d.           Housden 1982a
    1981                        7         0.4511                 14       (M)10                0.01-0.11     n.d.
                                2         2x0.4511                        (I+M)10              0.02-0.03     n.d.

    Denmark      25% E.C.       1         0.75                            96                   <0.02         n.d.           Kelly 1979g
    1979         40% E.C.       2         0.6                             76-86                <0.02-0.10    1.9-4.6        Richards 1980d
                 20% E.C.       1         0.6                             86                   <0.02-0.04    2.5-3.4
                 20% S.D.       2         0.28                            132-1399             <0.02         <0.02

    1982         45% E.C.       2         0.234                  3        75-87                <0.02-0.03    0.84-1.10      Housden 1982c
                                4         0.45                   4        61-80                <0.02-0.02    1.45-3.24
                                1         0.45                   1        60                   0.0514        3.02
                                2         2x0.45(14)                      61-73                <0.02-0.02    1.61-2.59

    France       25% E.C.       2         0.5                             62-74                <0.01-0.013   <0.01-0.053    Hayto 1978b
    1977                        2         1.0                             62-74                <0.01-0.023   0.01-0.153

    1978         25% E.C.       1         0.45                            64                   0.02-0.06     1.77-8.86      Kelly 1979h
                                1         0.9                             64                   0.02-0.08     2.67-10.48
                                1         2x0.45(19)                      62                   0.04-0.09     4.23-7.00
                                1         2x0.9 (19)                      62                   0.04-0.17     11.19-11.95
                                                                                                                                           

    Table 7 (continued)

                                                                                                                                           

    Country/     Formulation    No. of    Application rate2      No. of   Interval after          Residue (mg/kg)1          Reference
    Year                        trials    (kg a.i./ha)           samples  final application                            
                                                                          (days)               grain         straw
                                                                                                                                           

    1979         40% E.C.       2         0.45                   4        54-62                <0.02-0.17    5.76-10.81     Richards 1980a
                                2         2x0.45(21)5            6        38                   0.36-0.68     7.20-12.12
                 30% E.C.6      2         2x0.45(13-21)                   38-48                0.10-0.57     6.96-9.47

    Fed. Rep.    25% E.C.       1         0.5                    1        70                   <0.013        <0.013         Hayto 1979c
    of Germany                  1         0.7                    1        70                   <0.013        <0.013
    1977
    1980         40% E.C.       2         0.48                            77-79                0.02-0.06     0.06-1.0       Richards 1981b
                                2         2x0.48(19)12                    77-79                0.02-0.06     1.1 -1.3

    1981         40% E.C.       2         2x0.48(11-12)                   61-62                0.02-0.06     0.95-1.27      Browne 1982f

    1982         30% E.C.6      3         0.45                            62-76                <0.05         0.23-0.83      Housden & Longland
    1983

    Netherlands  45% E.C.       1         0.45                   3        70                   0.04-0.06     0.78-1.21      Reary 1981c
    1980

    Sweden       45% E.C.       4         0.45                            61-72                <0.0213       0.19-1.27      Longland 1983a
    1982                        2         2x0.225(8-15)                   53-55                <0.02         0.24-1.21
                                2         2x0.45(8-15)                    53-55                <0.02         0.34-2.86

    United       25% E.C.       3         0.4                             54-74                <0.013        <0.01-0.023,7  Hayto 1977a
    Kingdom                     4         0.5                             19-64                <0.013        0.01-0.023,13
    1976                        2         1.0                             64-74                <0.013        <0.013,20

    1977         25% E.C.       4         0.5                             76-78                <0.013        0.01-0.043      Hayto 1979c
                                2         1.0                             76-78                <0.01-0.01    <0.01-0.02

    1979         40% E.C.       3         2x0.4(18-29)                    36-63                0.06-0.32     3.0 -14.5      Richards 1980c
                                                                                                                                           

    Table 7 (continued)

    n.d. not determined.
    1/ Total residues of prochloraz and major metabolites, unless otherwise stated. Total residue measured as 
       2,4,6-trichlorophenol (BTS 45186) and converted to prochloraz-derived residue by correcting for the molecular 
       weight factor (x 1.906).
    2/ Figures in parenthesis indicate interval in days between applications.
    3/ Determination of free prochloraz residues only.
    4/ Prochloraz applies in mixture with fenpropimorph.
    5/ Prochloraz applied in mixture with mancozeb.
    6/ Co-formulation of prochloraz with carbendazim.
    7/ Results from two trials.
    8/ Rate of application in g a.i./kg seed.
    9/ Days after sowing treated seed.
    10/ Growth stages at application: M-heading, I-first joint.
    11/ Prochloraz applied in mixture with chlorothalonil.
    12/ Interval between treatments not given in one trial.
    13/ Results from three trials.
    14/ Residue analysis of whole ears.

    Table 8      Supervised Residue Trials with Prochloraz on Cereals at Harvest

                                                                                                                                             

    Crop      Country/    Formulation    Number of   Application rate   No. of   Interval after      Residue (mg/kg)1          Reference
              Year                       trials      (kg a.i./ha)       samples  application                            
                                                                        (days)                    grain         straw
                                                                                                                                             

    Rye       Austria       25% E.C.       1             0.5               1          91          0.013         <0.013         Kelly 1979a
              1977                         1             1.0               1          91          <0.013        <0.013

              Denmark       45% E.C.       2             0.45              2          72-77       <0.02-0.10    1.44-2.48      Housden 1982c
              1982

              Fed. Rep.     40% E.C.       2             0.48              4          89-109      0.03-0.05     0.39-0.53      Browne 1982d
              of Germany
              1981

    Oats      Denmark       45% E.C.       2             0.45              2          62          0.02-0.034    1.19-1.64      Housden 1982c
              1982

    Rice      Japan         25% E.C.       2             0.75             12          7-21        <0.01-0.043   n.d.           Gato 1980
    (brown,   1980          25% E.C.       2             3x0.75           12          7-21        <0.01-0.043   n.d.
    unpolished)             25% E.C.       2             25 g/hl2 +       12          7-21        <0.01-0.043   n.d.
                                                         3x0.75
                            25% E.C.       2             25 g/hl2          4          151-168     <0.013        n.d.
                                                                                                                                             

    n.d. = not determined.
    1/ Total residues of prochloraz and major metabolites, unless otherwise stated. Total residues measured as 2,4,6-trichlorophenol 
       (BTS 45186) and converted to prochloraz-derived residue by correcting for the molecular weight factor (x1.906).
    2/ 48-hour seed soak.
    3/ Determination of free prochloraz residues only.
    4/ Residue analysis of whole ears.

    Table 9   Summary of Residues in Mature Grain

                                                                             

    Crop         Application          No. of         Total residue (mg/kg)
                 (kg a.i./ha)         results                                
                                                     Mean       Std. Dev.
                                                                             

    Wheat        1  0.375-0.5          36           0.03         0.03
    Wheat        2  0.375-0.5          36           0.04         0.03
    Wheat        3  0.375-0.5          12           0.06         0.03
    Wheat        1  0.6-0.9            31           0.07         0.18
    Barley       1  0.4-0.5            42           0.03         0.03
    Barley       2  0.4-0.5            20           0.091        0.091
    Barley       1  0.6-0.9            14           0.03         0.03
    Barley       2  0.9                3            0.09         0.05
    Rye          1  0.48               2            0.04
                                                                             

    1/ Excluding a set of 11 results from four replicated applications
       of prochloraz alone and with mancozeb, which were exceptionally
       high (mean 0.42, std. dev. 0.18 mg/kg), residues in straw were not
       exceptionally high. The high grain results may reflect poor
       separation of grain and chaff in these samples (Richards 1980a).

    Table 10            Supervised Trials on Residue Decline with Prochloraz

                                                                                                                                              

    Crop      Country/    No of     Formulation    Application rate2                         Residues (mg/kg)1 after           References
              Year        trials                   (kg/a.i./ha)                             final application (days)
                                                                                                                          
                                                                                       35-36         56           75-85
                                                                                                                                              

    Wheat     Denmark     1         45% E.C.       0.45                 whole plant    1.62                                    Housden 1982c
    1982                                                                whole ears                   0.10
                                                                        straw                        2.01

                          2         45% E.C.       2x0.23(19)3          whole plant    0.33-0.94
                                                                        grain                                     <0.02
                                                                        straw                                     1.47-1.94

                          2         45% E.C.       0.23+0.45(19)3       whole plant    1.11-1.76
                                                                        grain                                     <0.02
                                                                        straw                                     1.87-2.36

                          2         45% E.C.       2x0.45(19)           whole plant    0.70-2.02
                                                                        grain                                     <0.02-0.02
                                                                        straw                                     1.56-2.07
                          2         45% E.C.       2x0.45(19)3          whole plant    1.38-1.44
                                                                        grain                                     <0.02
                                                                        straw                                     1.72-2.79
                                                                                                                                              

    Table 10 (Contd.)

                                                                                                                                               

    Crop    Country/  No. of   Formulation  Application2             After             After final application (days)              References
            Year      trials                rate                     penultimate
                                            (kg a.i./ha)             application
                                                                     (days)
                                                                                                                             
                                                                     20-29        0           15-22       37-42       54-63
                                                                                                                                               

    Wheat   Fed. Rep. 3        40% E.C.     2x0.48     green plant   0.80-1.644   1.62-2.554
            of                              (21-30)    ears                       0.15-1.114  0.27-1.494  0.23-0.844  0.06-0.084   Richards
            Germany                                    grain                                                          <0.02-0.06   1980g
            1979                                       straw                                                          1.0-5.9

                                                                     17-23        0           8-19        39-44       59-66
                                                                                                                             
            1980      3        40% E.C.     2x0.48     green plant   0.15-2.7
                                            (17-23)    green ears                 4.7 -13.6   0.84-2.2    0.28-0.61                Reary
                                                       grain                                                          0.01-0.04    1981b
                                                       straw                                                          0.7 -2.0

                                                                     7-13         0           8-19        39-44       59-66
                                                                                                                             
                      3        40% E.C.     3x0.48     green plant   0.2 -4.7
                                            (11-23/    green ears                 5.5 -16.8   0.61-3.3    0.35-0.58
                                            7-13)      grain                                                          0.03-0.06
                                                       straw                                                          1.1 -3.6

                                                                     8-19         0           7-14        31-46       58-64
                                                                                                                             
            1981      5        40% E.C.     3x0.48     green ears    0.16-0.96    3.87-12.50  2.42-5.85   0.31-1.16                Browne
                                            (11-29/    whole plant                                        0.51-3.789               1982e
                                            8-19)      grain                                              0.04-0.31   0.02-0.13
                                                       straw                                                          1.07-6.40
                                                                                                                                               

    Table 10 (Contd.)

                                                                                                                                               

    Crop    Country/  No. of   Formulation  Application2             After             After final application (days)              References
            Year      trials                rate                     penultimate
                                            (kg a.i./ha)             application
                                                                     (days)
                                                                                                                             
                                                                     28-30        0           12-14       21-48       43-60
                                                                                                                                               

            1981      2        40% E.C.     2x0.48     green ears    0.11-0.84    10.64-13.2  1.14-4.21   0.71-1.18                Browne
                                            (28-30)    whole plant                                        2.078                    1982f
                                                       grain                                              0.038       0.06
                                                       straw                                                          1.88-3.59

                                                                     6-19         0           7-14        21-48       43-60
                                                                                                                             
                      4        40% E.C.     3x0.48     green ears    2.96-8.27    13.90-21.40 3.61-7.25   0.49-2.32
                                            (9-22/     whole plant                                        1.74-3.614  2.317
                                            6-19)      green ears+                                        2.318
                                                       straw
                                                       grain                                              0.03-0.217  0.05-0.08
                                                       straw                                                          4.05-4.55
                                                       ears                                                           0.487

                                                                     0            17          42           57            85          
                                                                                                                                  
    Wheat   Fed.      3        30% E.C.5    0.45      whole plant    7.99-13.64   0.74-1.95   0.21-0.94    0.45.0.62                 Housden &
            Rep. of                                   grain                                                              <0.05       Longland
            Germany                                   straw                                                              0.08-0.27   1983
            1982

                                                                                  34-36       60-87
                                                                                                         
    Barley  Denmark   2        45% E.C.     0.233     whole plant                 0.64-0.74
            1982                                      grain                                   <0.02-0.03
                                                      straw                                   0.84-1.10

                                                                                                                                               

    Table 10 (Contd.)

                                                                                                                                               

    Crop    Country/  No. of   Formulation  Application2             After             After final application (days)                References
            Year      trials                rate                     penultimate
                                            (kg a.i./ha)             application
                                                                     (days)
                                                                                                         
                                                                                  34-36       60-87
                                                                                                                                               

                      5        45% E.C.     0.45      whole plant                 0.77-2.32
                                                      grain                                   <0.02-0.02
                                                      straw                                   1.45-3.24
                                                      whole ears                              0.058
                      2        45% E.C.     2x0.45    whole plant                 1.03-3.18
                                            (14)      grain                                   <0.02-0.02
                                                      straw                                   1.61-2.59

                                                                     19           0           13           33-34         77-79
                                                                                                                                    
            Fed.      2        40% E.C.     0.48      green plant                 5.1-10.1    0.4-1.5      0.6-1.7                   Richards 1981b
            Rep. of                                   grain                                                              0.02-0.06
            Germany                                   straw                                                              0.6-1.0
            1980      2        40% E.C.     2x0.48    green plant     1.1-3.4     3.2-5.0     1.5-2.5      1.3-2.1
                                            (19)6     grain                                                              0.02-0.06
                                                      straw                                                              1.1-1.3

                                                                     11-12        0           10-18        27-48         61-62
                                                                                                                                    
            1981      2        40% E.C.     2x0.48    green plant     0.91-7.99   10.40-18.60                                         Browne 1982f
                                            (11-12)   green ears                              0.52-3.62    0.07-0.50
                                                      ears + straw                                         0.218
                                                      grain                                                0.088         0.02-0.06
                                                      straw                                                              0.95-1.27
                                                                                                                                               

    Table 10 (Contd.)
                                                                                                                                               

    Crop    Country/  No. of   Formulation  Application2                               After final application (days)                References
            Year      trials                rate                    
                                            (kg a.i./ha)            

                                                                                                                                
                                                                     0            19          38-40        56            62-76
                                                                                                                                               

            1982      3        30% E.C.10   0.45      whole plant    5.25-10.38   0.21-1.78   0.13-0.80    <0.05-0.78                Housden &
                                                      grain                                                              <0.05       Longland 1983
                                                      straw                                                              0.23-0.83

                                                                                  35          72-77
                                                                                                       
    Rye     Denmark   2        45% E.C.     0.45      whole plant                 0.85-1.62
            1982                                      whole ears                              <0.02-0.10
                                                      straw                                   1.44-2.48

                                                                     0     11    21     34    55-56   69     83    89    93   109
                                                                                                                                  
             Fed. Rep.   1      40% E.C.    0.48      whole plant    9.6                1.16                             0.20         Browne 
             of                                       green ears                              0.03           0.02                     1982d
             Germany                                  ears                                                               0.03
             1981                                     grain                                                              0.03 0.05
                                                      straw                                                                   0.39
                         1      40% E.C.    0.48      whole plant    13.8  1.33                       0.05
                                                      green ears                 0.14         0.05
                                                      ears                                            0.02
                                                      grain                                           0.10         0.03
                                                      straw                                                        0.53

                                                                                        36-37         62
                                                                                                                
    Oats     Denmark     2      45% E.C.    0.45      whole plant                       0.37-0.88                                     Housden 
             1982                                     whole ears                                      0.02-0.03                       1982c
                                                      straw                                           1.19-1.64
                                                                                                                                             

    Table 10 (Contd.)

    1    Total residues of prochloraz and major metabolites, unless otherwise stated. Total residue measured as 2,4,6-trichlorophenol
         BTS 45186) and converted to prochloraz-derived residue by correcting for the molecular weight factor (x 1.906).
    2    Figures in parentheses indicate interval in days between applications.
    3    Prochloraz applied in mixture with fenpropimorph.
    4    Results from two trials.
    5    Co-formulation of prochloraz with carbendazim.
    6    Interval between treatments not given in one trial.
    7    Results from three trials.
    8    Result from one trial.
    9    Results from four trials.
    
    Table 11  Summary of Residues in Mature Straw

    Crop       Application         No. of      Total residue (mg/kg)
               (kg a.i./ha)        results     Mean     Std. Dev.
                                                                     
    Wheat      1  0.375-0.5       35          2.83     3.07
    Wheat      2  0.375-0.5       36          4.85     3.23
    Wheat      3  0.375-0.5       11          3.20     1.60
    Wheat      1  0.6-0.9         22          5.03     4.42
    Barley     1  0.4-0.5         20          3.30     3.05
    Barley     2  0.4-0.5         26          6.95     3.64
    Barley     1  0.6-0.9         13          3.36     1.92
    Barley     2  0.6-0.9         3           11.6     0.4
    Barley     1  0.48            2           0.46
                                                                     

         No information on good agricultural practice was available for
    the use of prochloraz on almonds. A 50 percent prochloraz-manganese
    complex is "recommended" as a foliar treatment at a 15-30 g a.i./hl
    application rate. Two applications at 3X this rate in one trial
    resulted in maximum residues up to 0.7 mg/kg (Table 2). The limit of
    determination has been estimated at 0.1 mg/kg although the apparent
    residues in an untreated control were 0.07 mg/kg. Recoveries from
    hulls amended with prochloraz at 1 mg/kg were 967 mg/kg.

    Oilseed Rape

         Information on good agricultural practice was available for
    prochloraz on oilseed rape from two countries, from which data on
    residue trials were also available. Residue data from 48 trials were
    also reported from two countries for which good agricultural practice
    was not known to the Meeting (Table 12). At preharvest intervals from
    25 to 266 days, residues of prochloraz and its metabolites, reflecting
    good agricultural practice, ranged from 0.01 to 0.33 mg/kg. Preharvest
    intervals, if applicable, were not provided. The limit of sensitivity
    was estimated at 0.05 mg/kg. However, since apparent residues in
    untreated controls ranged from <0.01-0.15 mg/kg (but were usually
    less than 0.05 mg/kg), a 0.2 mg/kg over-all limit of determination may
    be more realistic. Analytical recoveries were > 85  15 percent of
    amended levels of 0.2-1 mg/kg.

    Mushrooms

         Information on good agricultural practice and corresponding
    residue trials were available from two countries, as well as data from
    residue trials from another country (total of 31 trials, Table 13).
    The most common treatment was a single application of the 
    prochloraz-manganese complex formulation 1-10 days after casing at 1.5
    g a.i./l sq m with a 10-day preharvest interval, or three applications
    at 0.3 g a.i./l/m2, the first 1-10 days after casing and then after
    the first and second flush, with a two-day pre-harvest interval. A
    variation of the latter was also used at 2x 0.6 g a.i./l/sq m (Table
    1), also with a two-day preharvest interval. Data extracted from Table
    13 that reflect good agricultural practice are:


                                                                                                                           

    Country/            Applications        Residue (mg/kg)                   Interval after       Approved preharvest
                        and rate                                              last application     harvest
                        (g a.i./sq m)                                         (days)               interval (days)
                                                                                                                       

    The Netherlands     1 x 1.6             0.11-0.27   total residue              10                   10

    United Kingdom      2 x 0.6             1.4-1.6     total residue               4                    2
                                            0.6-0.8     free prochloraz

                        1 x 1.25            0.36        total residue              13                   10
                                            0.47        free prochloraz            28                   10
                        3 x 0.3             0.24-0.43   total residue               2                    2
                                            0.07-0.1    free prochloraz             6                    2
                                            0.4-1.4     free prochloraz             3                    2
                                                                                                                       

    Table 12  Supervised Residue Trials with Prochloraz on Rapeseed

                                                                                                                                      

    Country/    Formulation    No. of    Application rate2      No. of     Interval after       Residues1      References
    Year                       trials    (kg a.i./ha)           samples    final application    (mg/kg)
                                                                           (days)
                                                                                                                                      

    France      40% E.C.       2         0.45                   8          73                   0.02-0.04      Cron 1982
    1980/1                     2         0.453                  8          73-76                0.01-0.03
                               1         0.60                   4          73                   0.02-0.03

                30% E.C.4      2         0.45                   8          73-76                0.02-0.03

    1982        40% E.C.       4         0.45                   12         37-51                0.03-0.15      Peatman & Snowden 1982
                               4         0.453                  12         37-51                0.03-0.13
                               4         2x0.45 (12-15)         12         25-38                0.04-0.32
                30% E.C.4      4         2x0.45 (12-15)         12         25-38                0.06-0.33

    Denmark     45% E.C.       3         0.45                   6          70-76                <0.05          Peatman & Snowden 1983
    1982                       3         2x0.45 (18-23)         7          53                   0.07-0.19

    Sweden      45% E.C.       3         0.45                   6          47-72                0.12-0.28      Peatman & Snowden 1983 
    1982

    United      40% E.C.       3         0.45                              238-266              <0.05-0.07     Manley & Snowden 1982c
    Kingdom                    3         0.45                   3          119-133              <0.05-0.19
    1981/2                     3         2x0.4(91-109)5         3          119-133              <0.05
                               3         3x0.4(91-109/          3          64-75                <0.05-0.09
                                         51-58)5
                               2         3x0.4(92-103/          2          72-73                <0.05-0.06
                                         51-57)
                               2         3x0.5(92-103/          1          72-73                0.06
                                         51-57)
                                                                                                                                      

    Table 12 (continued)

    1    Total residues of prochloraz and major metabolites, measured as 2,4,6-trichlorophenol (BTS 45186) and converted to 
         prochloraz-derived residue by correcting for the molecular weight factor (x 1.906).
    2    Figures in parentheses indicate interval in days between applications.
    3    Prochloraz applied in mixture with mancozeb.
    4    Co-formulation of prochloraz with carbendazim.
    5    Prochloraz applied in mixture with tolclofos methyl.

    Table 13  Supervised Residue Trials with Prochloraz on Mushrooms

                                                                                                                                               

    Country/    No. of   No. of    Application rate (a.i.)                  Residues (mg/kg)1 days after final application             References
    Year        trials   samples   and timing2                                                                                      
                                                                   3         5       10       14        20         21     27    45
                                                                                                                                               
    Australia   1                  1.25g/sq m at casing                                                 0.1               0.1   <0.1    Housden 
    1981        1                  2.50g/sq m at casing                                                 0.23              0.13  0.14    1982
                1                  1.25g/sq m at casing +
                                   0.63g/sq m after first flush    0.41-0.63                                       0.22
                                   (24-day interval)

                1                  2.50g/sq m at casing +
                                   1.25g/sq m after first flush                                                    1.16-1.63
                                   (24-day interval)

                1                  2.50g/sq m at casing +
                                   2.50g/sq m after first flush                                                    <0.1
                                   (24-day interval)

                1                  0.63g/sq m after first flush    1.06-2.98
                1                  1.25g/sq m after first flush    4.48-4.61
                1                  1.25g/sq m after first flush+
                                   0.63g/sq m after second flush                              0.29
                                   (7-day interval)

                1                  2.50g/sq m after first flush+
                                   1.25g/sq m after second flush                              0.37
                                   (7-day interval)

    The         1        4         1.6g/sq m before inoculation                      0.11-0.27                                          Browne 
    Netherlands 1        4         0.75g/sq m before inoculation+  0.15-0.24                                                            1982
    1980                           0.75g/sq m 14 days later

                         4         0.75g/sq m before inoculation+
                                   0.75g/sq m after first flush    0.15-1.14
                                   (23-days interval)
                                                                                                                                               

    Table 13 (Continued)

                                                                                                                                               

    Country/    No. of   Application rate (a.i.)                             Residues (mg/kg)1 days after                       References
    Year        trials   and timing2                            1st application    2nd application    3rd application
                                                                19                 7                  4
                                                                                                                                               

    United      1        0.61g/sq m after casing +              0.04               0.10               0.08                      Richards 1981c
    Kingdom              0.61g/sq m after first flush +
    1980                 0.61g/sq m after second flush
                         (19- and 10-day intervals)

                                                                  1st application                2nd application
                                                                  21       28              4           12          18
                                                                                                                        
                1        0.61g/sq m after casing +                0.04     0.04-0.11       1.37-1.58   <0.02
                         0.61g/sq m after second flush
                         (31-day interval)

                14       0.61g/sq m after casing +                0.013    0.01-0.33       0.56-0.803  0.08-0.333  0.05-0.183     Whiteoak 1981
                         0.61g/sq m after second flush
                         (31-day interval)

                                                                           Days after application
                                                                  28       35              43          49
                                                                                                                    
                1        1.25g/sq m 7 days after inoculation      0.473    0.043           0.27-0.323  0.203
                1        0.625g/sq m 7 days after inoculation     0.133    0.103           0.093       0.07-0.083

                                                                  2nd application          3rd application
                                                                  13                       6           14          20
                                                                                                                          
                1        0.625g/sq m 7 days after inoculation     0.193    0.22-0.243      0.033       0.27-0.323
                1        + 2x0.313g/sq m at 14-day intervals
                         thereafter
                1        0.313g/sq m 7 days after inoculation
                         + 2x0.313g/sq m at 14-day intervals      0.133                    0.07-0.103  0-323       0.053
                         thereafter
                                                                                                                                               

    Table 13 (Continued)

                                                                                                                                               

    Country/    No. of   Application rate (a.i.)                               Residues (mg/kg)1 
    Year        trials   and timing2                                         Days after application
                                                                  2nd application          3rd application
                                                                  5        12              3           14          21
                                                                                                                            

    1981        1        0.15g/sq m five days after inoculation   0.323    0.123           0.62-0.653  0.193       0.093          Whiteoak 1981
                         + 2x0.15g/sq m at 18- and 14-day
                         intervals thereafter

                45       0.3g/sq m + 2x0.3g/sq m. Timing as    0.20-0.373 0.11-0.643       0.39-1.443  0.10-0.313  0.06-0.073
                         given above
                1        0.9g/sq m + 2x0.3g/sq m. Timing as       0.423    0.213           1.293       0.543       0.21-0.243
                         given above
                1        1.5g/sq m + 2x0.3g/sq m. Timing as       0.273    0.523           0.993       n.d.        0.063
                         given above
                1        3.0g/sq m + 2x0.3g/sq m. Timing as       0.623    0.543           0.743       0.343       0.953
                         given above
                                                                                                                                               

    Table 13 (Continued)

                                                                                                                                               

    Country/  No. of  Application rate                            Residues (mg/kg)1 days after                                      References
    Year      trials  (a.i.) and timing2      1st application          2nd application                   3rd application
                                              13-14 15-16 18   3     5    7    10    12-13 14-16 2    3-4  7    9-10 12   14   17   
                                                                                                                                               

    United    1       0.3g/sq m 7 days after  0.24  0.20  0.79 0.426 0.30 0.30 0.377 0.23  0.51  0.43 0.33 1.03 0.32 0.23 0.28 0.22 Housden
    Kingdom           casing + 2x0.3g/sq m                                                                                          &
    1981              at 18- and 14-day                                                                                             Whiteoak
                      intervals thereafter                                                                                          1982

    1982      1       0.3g/sq m 7 days after  0.26 0.14        0.85       0.24 0.24  0.26  0.58  0.24 0.61  0.45 0.61
                      casing + 2x0.3g/sq m                    (0.57)8                           (1.11)8
                      at 15- and 17-day
                      intervals thereafter

                                                                          Residues (mg/kg)1 days after application
                                                            13    15    18    22    25     28     31     34    36    39    42
                                                                                                                                
    1982     1        1.25g/sq m 7 days after casing        0.36  0.25  0.33  0.30  0.20   0.38   0.42   0.28  0.54  0.22  0.33
                                                                                                                                               

    Table 13 (Continued)

    n.d. = not determined.
    1    Total residues of prochloraz and major metabolites, unless otherwise stated (see note 3).  Total residue measured as
         2,4,6-trichlorophenol (BTS 45186) and converted to prochloraz-derived residue by correcting for the molecular weight factor (x1.906).
    2    All treatments used the prochloraz-manganese complex 50% W.P. formulation.
    3    Determination of residues of free prochloraz only.
    4    Samples of mushroom also analysed for total residues of prochloraz and metabolites (see Richards 1981c)
    5    Mean residue levels from four trials using spray volumes of 100, 200 or 400 l/sq.m.
    6    Mean residue level in small and larger mushrooms (0.43 and 0.40 mg/kg respectively).
    7    Mean residue level in small and larger mushrooms (0.52 and 0.21 mg/kg respectively).
    8    Mushroom emerged before treatment (direct application).
    
         Therefore, residues of prochloraz and its metabolites or of
    prochloraz alone may be at least as much as 2 mg/kg from approved
    practices. Differences between residues of prochloraz and its
    metabolites, compared to free prochloraz, do not appear to be as high
    as in cereals. Analytical recoveries of total residues were generally
    > 70 percent, with apparent residues of 0.03  0.02 mg/kg in
    untreated controls and > 77 percent and 0.01 mg/kg for free
    prochloraz.

    FATE OF RESIDUES

         The fate of prochloraz has been studied in plants and animals. In
    plants, it is metabolized to 
    N-formyl-N'-1-propyl-N-(2-(2,4,6-trichlorophenoxy)ethyl) urea,
    also known as BTS 44596 or the "formyl urea"; to 
    N-propyl-N-(2-(2,4,6-trichlorphenoxy)ethyl) urea, also known as
    BTS 44595 or "the urea"; to 2,4,6-trichlorophenoxyacetic acid (BTS
    9608), and finally to 2,4,6-trichlorphenol (BTS 45186), all of which
    form stable conjugates (Figure 1). Animal metabolism has resulted in
    characterization of urinary metabolites (see Figure 1 under
    "Toxicology"), information of radioactivity distribution in tissues
    from oral or dermal administration and rate and route of excretion.
    Qualitatively, urinary metabolites are similar among several test
    animals, although the major plant metabolites have not been identified
    in the urine. Residues in animal tissues have not been identified.

         Metabolism studies have also been conducted on the major plant
    metabolite BTS 44596.

    In Animals

         Metabolism of prochloraz in rats, dogs, rabbits, mice and pigs is
    discussed under "Biochemical Aspects".

    Goat

         A study was conducted to indicate the level of residues that
    might occur in tissues and milk of lactating ruminant animals after
    ingestion of prochloraz. A lactating goat was given two 60 mg oral
    doses of 14C-phenyl labelled prochloraz by gelatin capsules, with 13
    days between doses. The dosage was designed to reflect possible
    residues resulting from consumption of 3 kg of straw with residues of
    20 mg/kg of prochloraz at each dosing (versus maximum straw residues
    of 12 mg/kg). Milk and plasma samples were taken at appropriate
    intervals after each dose and tissue samples 24 h after the second
    dose. After the first dose, residues of prochloraz equivalent in milk
    decreased from 0.04 mg/kg after 8 h to 0.01 mg/kg (limit of
    determination) after 48 h. Milk residues were 0.01 mg/kg and 0.03
    mg/kg at 2.5 and 18.5 h, respectively, after the second dose. In
    tissues, residues of prochloraz equivalent were 1.7 mg/kg in liver,
    0.2 mg/kg in kidney, 0.36 mg/kg in adrenal, <0.05 mg/kg in fat,
    0.03 mg/kg in muscle and <0.2 mg/kg in other tissues. Rumen
    contents contained prochloraz equivalent of 0.65 mg/kg and bile 5.4
    mg/kg. Residues were not characterized or identified (Campbell 1980).

         A second and similar experiment was conducted using the
    photodegradant and plant metabolite BTS 44596, with an interval of 8 h
    between doses. Results were similar to those for prochloraz, although
    the higher maximum milk residues of 0.07 mg/kg BTS-44596 equivalent 7
    h after dosing decreased somewhat more rapidly (< 0.01 mg/kg after
    31 h). Residues of BTS-44596 equivalent in tissues were somewhat less
    than for prochloraz (liver 0.59 mg/kg, kidney 0.12 mg/kg, fat <0.01
    mg/kg, muscle <0.01 mg/kg and less in other tissues as well),
    Residues were not identified or characterized (Campbell & Needham
    1980).

         In another study a lactating goat was fed ad libitum for four
    days with wheat straw containing 19 mg/kg field-incurred 
    14C-prochloraz equivalent residues. The straw was harvested at
    maturity 11 weeks after treatment at an equivalent rate of 0.94 kg
    a.i./ha (twice the recommended rate), Actual straw consumption was
    approximately 300 g/day (or approximately 6 mg of prochloraz
    equivalent/day), in addition to 1 700 g additional feed made available
    daily. After four days, maximum tissue residues of prochloraz
    equivalent, as determined by liquid scintillation counting was liver
    0.05 mg/kg, kidney fat 0.04 mg/kg and 0.03 mg/kg in other tissues,
    with a reported limit of determination of 0.02 mg/kg. Bile and rumen
    residues were 0.12 and 0.13 mg/kg, respectively. Maximum residues in
    milk were 0.006 mg/l and in plasma 0.079 mg/l. The limit of
    determination for milk was 0.001 mg/kg in this experiment. Residues in
    milk were relatively consistent over the four-day feeding period. Milk
    residues were 0.002 mg/kg prior to the feeding of treated straw
    (Campbell 1983).

    In Plants

         The fate of prochloraz has been studied in wheat (various
    stages), citrus and apples. Soil uptake by sugar beet, which
    represents a likely rotational crop, was also studied. The metabolic
    fate in plants is illustrated in Figure 1.

    Wheat

         Wheat plants grown under glass were syringe treated at the sixth
    leaf stage with a 25 percent a.i. formulation of 3H-labelled
    prochloraz (labelled in the 3 and 5 positions of the benzene ring) at
    a rate equivalent to 1 kg/ha. After 19 days, the green wheat tissue
    was harvested and residues characterized and quantified by a variety
    of analytical techniques. Neutral, acid and basic fractions were
    analysed, with and without acid hydrolysis. After 19 days, 82.6
    percent of the applied radioactivity remained and 96.7 percent of this
    was extractable by the analytical procedures used (acetone-water
    extraction). The principal residue was free BTS 44596, closely
    followed by free and conjugated residues of BTS 44595, with lower
    levels of free prochloraz and free and conjugated trichlorphenol,
    conjugated trichlorophenoxyacetic acid and seven unknowns. Terminal
    prochloraz equivalent was 7 mg/kg. Individual residues were:

                                                                      % of applied    % of terminal
                                                                  radioactivity   residue*

    BTS 44596:   N-formyl-N'-l-propyl-N-(2-(2,4,6-
                 trichlorophenoxy) ethyl) urea            free        31.6           41

    BTS 44595:   N-propyl-N-(2-(2,4,6-trichlorophenoxy)   free        11             13
                 ethyl) urea                              conj.       19.5           23.1

    BTS 45186:   2,4,6-trichlorophenol                    free         1.4            1
                                                          conj.        6.8            4.9

    BTS 9608     2,4,6-trichlorophenoxy-
                 acetic acid                              conj.        0.21           0.2

    BTS 40542:   Prochloraz (unchanged)                   free         1.1            1.5

    Unknown (seven)                                                    5.5            7.7
    Radioactivity undetected                                           0.93           1.3
    Radioactivity unaccounted for                                      4.56           6.3

                                                                      82.6          100.0

    * Expressed as prochloraz equivalents
    
         None of the seven unknowns exceeded 4.3 percent of the terminal
    residue. Analysis of barley plants treated in a similar manner
    suggests that over 86 percent of the radioactivity applied to foliage
    was absorbed by the leaf within 24 h (McDougall 1979).

         In another study, separate plots of wheat at the flag leaf sheath
    opening stage were treated with a 25 percent a.i. formulation of
    either 3H-prochloraz labelled in the 3 and 5 positions of the phenyl
    ring or 14C-prochloraz labelled in the 2 position of the imidazole
    ring, at an equivalent rate of 1 kg a.i./ha. Mature wheat was
    harvested 13 weeks after treatment and the grain, straw and chaff were
    analysed.

         Total residues, expressed as prochloraz equivalents, from the
    phenyl-labelled prochloraz were grain 0.26 mg/kg, chaff 13.2 mg/kg and
    straw 26.5 mg/kg. An almost identical distribution resulted from the
    14C-prochloraz treated wheat. From the 3H-prochloraz treated wheat 
    76-80 percent of the recovered radioactivity was extractable from both
    straw and grain. Attempts to hydrolyse polar fractions with HC1 were
    unsuccessful, but better results were achieved with pyridine
    hydrochloride, which hydrolyses conjugated residues containing the
    2,4,6-trichlorophenyl moiety. The procedure liberates 
    2,4,6-trichlorophenol from both prochloraz and any metabolites
    containing the 2,4,6-trichlorophenyl moiety. Results of the analysis
    of the 3H-prochloraz treated wheat, expressed as a percentage of
    recovered radioactivity in mature tissue, are summarized below:

    FIGURE 1

                                                          Straw               Grain
                                                                                    

    Free 2,4,6-trichlorophenol (BTPS 45186)       5.2       4.1         3.4        8.4

    Residues containing the BTS-45186 moiety     58        37.9        53.9       39.5

    Tritiated water                               4.8       -           4.2        -

    Unidentified extractable residues             9.1      34          15.5       32.1

    Unidentified residues in solids              22        24          24.7       20

                                                 99.1     100         101.7      100
    
         Of the unidentified extractable residues no one of the grain or
    straw acidic, basic, volatile or aqueous fractions analysed contained
    more than 6.2 percent of the total residue.

         Formation and analysis of the glucosazone after hydrolysing
    starch extracted from the 14C-prochloraz treated grain demonstrated
    that 32.4 percent of the grain radioactivity was incorporated into the
    starch molecules. This is thought to result from the incorporation of
    14C-carbon dioxide, resulting from decarboxylation of the metabolite
    BTS 44596. The remaining residues were separated into various
    fractions but were not identified (Kelly 1980d; Kelly & Krepski 1980).

         When wheat seeds were treated at an equivalent rate of 0.4
    a.i./kg seed (approximating recommended usage) with a 20 percent a.i.
    liquid seed dressing and grown to maturity, residues at maturity (29
    weeks) were:

                   % of total       Prochloraz
                   applied      Equivalents (mg/kg)
                                Treated    Controls

    Soil           583         0.06       -
    Roots          15.1         1.5        -
    Chaff          0.1          0.04*      0.004*
    Grain          0.04         0.004*     0.002*
    Total aerial   6.6          0.16       -

    *    mean of four determinations.


         Translocation into the aerial portion of the plant was complete
    after six weeks (Krepski 1982).

         Potted wheat seeds were allowed to germinate under glass after
    soil surface drench application of a diluted 3H-prochloraz
    formulation. Approximately 82 percent of the radioactivity (0.8
    percent of applied) was retained in the root system at harvest after
    21 days. Residues decreased with increased distance of plant parts
    from the root system; they decreased from 8.7 percent of residues
    recovered in leaves 1 and 2, 0.62 percent in leaf 3, to 0.08 percent
    in leaf 7. Soil contamination was suspected of contributing some of
    the residues for leaves 1 and 2 and lower plant parts.

         In this same report a 3H-prochloraz formulation was applied with
    a syringe at the fifth leaf stage to the third leaf of similarly grown
    wheat without the soil drench. Plant parts were harvested and analysed
    after 24 days; 99 percent of applied radioactivity was retained in
    leaves 3 and 4 (difficulty was encountered in discerning leaves during
    applications). Radioactivity decreased from 0.03 percent of that
    applied in leaf 5 to 0.01 percent in leaf 9 and increased from 0.23
    percent in leaves 1 and 2 to 0.33 percent in the roots (McDougall
    1980a).

         After spring wheat harvest from soil plots treated at a rate
    equivalent to 1 kg/ha with either imidazole ring-labelled 
    14C-prochloraz or phenyl-labelled 3H-prochloraz, the plots were 
    re-sown with winter wheat and reharvested 10 months later. Soil
    samples at harvest of the winter wheat were 0.11 and 0.43 mg/kg for
    14C and 3H treatments, respectively. Residues of 14C or 
    3H-prochloraz equivalent were < 0.01 mg/kg in grain, chaff and
    straw. Grain control values were about half that for grain, but not
    statistically different. Low uptake is suggested for 3H-prochloraz
    treated chaff and straw where experimental levels are 50 to 100 times
    that of the respective controls (Krepski 1981a).

         A 1.5 sq m plot was treated with 14C-phenyl labelled prochloraz
    formulation by garden sprayer at an application rate equivalent to 395
    g a.i./ha, which approximates recommended usage for cereals. After 41
    days the soil was turned by hand and sown with sugarbeets as a
    representative rotational crop. A control plot was also planted.
    Seedlings were sampled 23 days after planting and mature plants (roots
    and foliage) at 157 days after planting.

         Residues at planting in soil averaged 0.26 mg/kg prochloraz
    equivalents. At 23 days after planting, residues of 0.07 mg/kg in
    seedlings were significantly greater than the 0.006 mg/kg controls. At
    harvest, residues of 0.005 mg/kg in the soils were not significantly
    different than in controls, whereas the 0.0052 mg/kg prochloraz
    equivalent in foliage was slightly greater than the 0.003 mg/kg
    control. This difference is statistically significant, although
    residues in the foliage are less than the background level (McGibbon
    1982).

    Citrus

         3H-prochloraz, a 2.5 percent E.C. formulation, was applied by
    pipette wash, to simulate a 0.1 percent a.i. postharvest commercial
    treatment, to Washington Navel oranges in Spain. Storage was at 4C in
    the dark from 10 to 60 days and at 20-22C in diffuse light. From 1 to
    10 days, surface residues were removed with a 0.1 percent ethylan BCP
    solution and those in peel and flesh by extraction with 90 percent
    acetone. Surface residues at room temperature decreased from 5.8
    percent of applied radioactivity at 1 day to 0.8 percent at 10 days,
    and at 4C from 3.8 mg/kg at 10 days to 1.1 mg/kg at 60 days.
    Corresponding residues in the flesh increased from 1.8 percent to 5
    percent of the applied dose over the storage period for room
    temperature storage, but remained relatively constant at approximately
    1.6 percent over the entire 60 day storage period at 4C.
    Radioactivity in the peel remained relatively constant at 92.3-96
    percent of the applied dose over the room temperature storage period
    and, similarly, 94.7 to 97.2 percent over the storage period at 4C
    (Kelly 1980a). Similar unlabelled studies on citrus residues during
    storage are reported under "In Storage and Processing".

    Apples

         Formulations of phenyl-labelled 14C-prochloraz or its manganese
    complex BTS 46828 were applied to individual apples under glass at
    rates approximating commercial usage. In samples analysed after 20
    days, residue distribution was similar in the surface, peel and flesh
    from either chemical. Residues in extracts from the prochloraz-treated
    apples (86 percent of the applied dose was recovered) were - wash 7.4
    percent, peel 50 percent and flesh 16.9 percent (20 percent of
    recovered). BTS 46828 gave almost identical results (Krepski 1981b).

         In similar experiments (not carried out under glass) the
    metabolism of prochloraz and its manganese complex were compared at
    intervals between 0 and 54 days after application by syringe to
    individual apples. Radioactivity distribution was again shown to be
    similar from use of either chemical, although prochloraz from the E.C.
    formulation was initially absorbed into the peel at a faster rate than
    the Mn-complex W.P. and was somewhat more persistent. The manganese
    complex was also more susceptible to losses from precipitation shortly
    after application. As a percent of radioactivity recovered at 0 and 54
    days, residues were:

                    Prochloraz             Mn - complex
                 *day 0    day 54        *day 0    day 54

    surface      32.3      1.9           67.6      1.2
    flesh        0.0       0.8           0.0       1.2
    peel         67.2      81.2          32.4      56.2

    Total        100       83.9          100       58.6

    * 5 hours (McDougall 1980b).

         In another similar study distribution and characterization of
    residues were investigated in two apple varieties at intervals ranging
    from 16 to 63 days after application by syringe of the Mn-complex to
    individual growing apples. As a percent of the applied dose,
    representative residues were:

                                                                 

      Days after  Whole                  Peel
      treatment   fruit      Flesh       Total      Extractables
                                                                 

      16          72 (83)    15.81       67 (78)    51.3 (61.4)
      33          54.8 (76)  3.6 (5.2)   51 (71)    37.2 (55.2)
      63          63.5       5.4         60         38
                                                                 

      Numbers in parentheses correspond to the Worcester variety and
    others to the Cox variety.

      Extractable residues in peel were quantified and characterized in
    both varieties at 33 and 63 days after treatment. As a percent of
    extractable peel residues the metabolic profile at 63 days for the Cox
    variety was:

    Metabolite                                  Percent

    Prochloraz or Unchanged BTS 46 828            5   )
    BTS 45186 (free 2,4,6-trichlorophenol)       11.5 )
    BTS 44595                                    15.2 )
    BTS 44596                                    33.1 ) >77.8
    Conjugated residues containing                    )
    the BTS 45186 moiety                         13   )
    Unidentified polar metabolites                6
    "Unknowns"                                    1.6,0.7
    Unresolved background                        13.9
    Total unidentified (excluding conjugates
    with BTS 45186)                              22.2

                                                100.0 

         Results were similar at 33 days for both varieties, except that
    conjugated residues containing the BTS 45186 moiety were only 3
    percent for the Worcester variety, only the first "unknown" was
    observed in Cox and the first and a different second "unknown" was
    found in Worcester. None of the residues exceeded 2 percent (Kelly
    1982a).

    In Soil

         Prochloraz 25 percent E.C. formulations, labelled with 14C in
    the imidazole ring and separately in the phenyl ring with 3H, were
    separately applied to acidic sandy loam and silty clay loam soils in
    enclosed jars purged with CO2-free air under laboratory conditions
    for up to 52 weeks. Application was at 6 mg/g soil, equivalent to 0.7
    kg a.i./ha (a recommended crop application rate). Silty clay loam was
    similarly treated with prochloraz labelled with 14C in the phenyl
    ring and studied over 9 months.

         Radioactivity losses as volatiles were about 50 percent of the
    applied dose to silty clay for both 14C-imidazole and 3H-phenyl
    labelled prochloraz after one year, as was the case for the 
    14C-phenyl labelled formulation at 9 months. Losses were more rapid
    from silty clay loam than from sandy loam, for which losses were half
    or less that in silty clay. Experimental evidence indicated, but did
    not prove, that volatiles from 14C-phenyl and 14C-imidazole labelled
    prochloraz were predominantly CO2. In the case of 3H-phenyl labelled
    prochloraz, evidence suggests volatile radioactivity in the form of
    tritiated water. The major extracted residue in all cases was
    prochloraz per se at 50-68 percent of the applied dose (80-90
    percent of extracted) after 8 weeks to 12-30 percent (45-67 percent of
    extracted) after 52 weeks. Lower residues of BTS-44596 and BTS 45186
    combined were <18 percent of the applied dose (<26 percent of
    extracted) after 52 weeks for 3H-labelled treatments. Binding was
    more pronounced in sandy loam. The half-life was reported as 3 and 5
    months, respectively, in silty clay and sandy loams. In both cases the
    acidic pH would increase stability (Kesterton 1981a).

         In German standard soils the half-life of unlabelled prochloraz
    ranged from 115-135 days, with stability directly related to organic
    matter content. For both soils the pH was acidic, which is conducive
    to prolonged stability (McGibbon 1982).

         14C-imidazole and 3H-phenyl labelled prochloraz, formulated as
    a 25 percent E.C., were incubated under anaerobic conditions at a rate
    equivalent to 0.7 kg a.i./ha and sampled at 14, 27 and 60 days.
    Residues of prochloraz remained relatively constant over the test
    period in silty clay loam (ca 68 percent of the applied dose) and
    decreased slightly (to ca 54 percent) in silty clay loam. The decrease
    in silty clay loam was accompanied by an increase in bound residues.
    Anaerobic conditions halted the continuous degradation and formation
    of volatiles observed under aerobic conditions. Other components
    indicated by TLC from 3H treatments were BTS 44596 and BTS 45186 at
    approximately 6 and 3 percent of the applied dose, respectively,
    whereas from 14C treatments prochloraz, imidazole and BTS 44596 were
    approximately 68, 2 and 1 percent, respectively (Kesterton 1981b).

         The absence of significant degradation of a 14C-phenyl labelled
    2.5 percent E.C. prochloraz formulation in sandy loam and silty clay
    loam under sterile soil conditions for 30 days suggests that
    degradation is facilitated primarily by soil microorganisms as opposed
    to chemical degradation, at least under the experimental conditions
    (acidic pH and 50 percent soil moisture capacity) (Newby 1982).

         Sandy loam and silty clay loam soil were treated with a 
    14C-benzene labelled 25 percent E.C. prochloraz formulation at a rate
    equivalent to 0.44 kg a.i./ha, aged 13 days, added to the top of 30 cm
     7 cm diameter columns containing untreated soil and eluted with an
    equivalent of 1.5 cm rain for 18 days. Essentially all radioactivity
    was retained in the top 5 cm of soil, with less than 0.3 percent of
    the applied amount being detected in leachate (Kesterton & Newby
    1980a).

         In a similar soil column study, except that the equivalent
    application rate was 0.8 kg/ha, the labelled prochloraz was applied to
    the same silty clay loam and aged for 30 days, after which it was
    eluted for 45 days with a daily equivalent of 0.5 cm rainfall. Results
    were similar to the first study in that <0.05 percent of the
    applied dose was detected in the eluant. However, even though 88-94
    percent was in either the treated portion or the first 5 cm below it,
    0.3-0.6 percent was detected in the bottom 25 cm, indicating some
    downward mobility other than that detected in the leachate (Kesterton
    & Newby 1981).

         When an unlabelled prochloraz formulation was applied to West
    German standard soil columns at a rate equivalent to 1 kg/ha, <0.05
    percent was detected in the leachate (Maier-Bode 1980). In a similar
    experiment leachate contained <1.7 percent of the applied dose
    (Stockbauer 1983). Details of the preceding two experiments were not
    available.

         In soil thin-layer mobility tests, the mobility of prochloraz and
    soil metabolites BTS 44 596 and BTS 45186 were compared to that of
    atrazine and 2,4-D in four soil types. According to the Helling
    mobility index, over-all mobility in the four soils were, in order of
    increasing mobility, prochloraz, BTS 44596 (low mobility), BTS 45186
    (low mobility), atrazine (intermediate mobility) and 2,4-D (mobile).
    Mobility of all tested materials was greatest in sand (even BTS 44596
    and BTS 45186 would have intermediate mobility). Prochloraz and BTS
    44596 were immobile in silt loam, whereas BTS 45186 was of
    intermediate mobility. The thin-layer studies confirmed the low, but
    positive, mobility detected in soil column experiments (Leake & Lines
    1981).

         Adsorption/desorption of prochloraz, uniformly labelled in the
    phenyl ring and applied as an E.C. formulation to a sandy loam and
    silty clay loam, was investigated. The Kd of the sandy and silty
    soils were 152 and 256, respectively, indicating slightly more
    adsorption by the latter. The K values were 86.8 and 101.7,

    respectively, for these soils. Strong adsorption and minimal
    desorption is consistent with leaching studies (Kesterton & Newby
    1980b).

         A trichlorophenol tritiated ring prochloraz E.C. formulation was
    applied to one sq m plots of barley and wheat in sandy loam at an
    equivalent rate of 1 kg/ha. Core samples from 32.5 cm deep were
    analysed after approximately 15 and 30 weeks; > 95 percent of
    prochloraz residues were found in the upper 10 cm and in some cases
    the top 2.5 cm. Somewhat similar distribution after 15 and 30 weeks
    suggests only slight leaching of bound residues as a result of
    additional (over 150 mm) rainfall in the latter period (Kesterton
    1978).

    In Water

         No degradation of prochloraz was observed after 30 days in 22C
    buffer solutions at a pH of 4.95 or 6.98. At pH 9.18 degradation does
    occur, with 77 percent of the added prochloraz remaining after 30
    days. A first order degradation was indicated and a half-life
    estimated of approximately 79 days. The only degradant 
    N-propyl-N-2-(2,4,6-trichlorophenyl) ethylamine (BTS 40348) was
    reported to account for more than 2 percent of the total
    radioactivity, although the quantitative analyses were not provided
    (Kelly 1982b). The 4:1 manganese complex of prochloraz (BTS 46 828),
    either as active compound or as a 50 percent W.P. formulation,
    disassociated to prochloraz and manganous chloride in the presence of
    water (pH 6.1). Approximately 50 percent of the complex was
    dissociated within four hours at 25C (Whiting & Dickinson 1979).

         Biodegradability of prochloraz in water was studied using the
    closed bottle test according to OECD Guideline 301D. Tests indicate
    little biodegradation at 20C up to 15 days after inoculation, but 13
    percent degradation by 28 days, suggesting some initial bacterial
    adaptation (Douglas & Pell 1982). When bacteria preadapted to
    prochloraz were used as the inoculum, degradation commenced
    immediately and reached 47 percent biodegradation by 28 days (Douglas
    & Pell 1983).

    In Storage and Processing

    Processing

    Citrus - Oranges were postharvest brush-treated at 1 000 mg/kg with
    a 40 percent E.C. formulation and processed into "42% comminuted
    orange" and "special whole orange compound". These "whole oranges
    juices" (chopped oranges) are used for production of various orange
    drinks and utilizes most of the whole orange, except for removal of
    some coarse peel. It includes a pasteurization process up to 86C,
    depending on which of two processes were used. Total residues
    (converted to 2,4,6-trichlorophenol for analysis) were 0.19 and 0.14
    mg/kg expressed as prochloraz for the 42 percent comminuted orange and
    special whole orange compound, respectively, approximately 30 percent
    of the residues found in whole oranges (Manley & Snowden 1982b).

    Cereals - Winter wheat was treated post-emergence at two sites in
    the Federal Republic of Germany at growth stage 59 (mid-May to 
    mid-June) with three applications of a 40 percent E.C. prochloraz
    formulation at the 0.48 kg/ha rate recommended in that country. Mature
    grain was sampled at 57-58 days after last application and portions
    milled and baked into bread. Total residues were determined by
    hydrolysis of the trichlorophenol containing moieties followed by EC
    analysis and use of a 1.906 factorial conversion to a prochloraz
    equivalent basis. Residues in grain and bread were <0.1 mg/kg, the
    limit of determination.

         Under similar conditions prochloraz was applied twice to barley.
    Total residues in barley malt, expressed as prochloraz, were 0.13 and
    0.15 mg/kg compared with 0.07 mg/kg in a control. Limit of
    determination was 0.1 mg/kg.

    Rapeseed Oil - Mean residues of total prochloraz and metabolites
    hydrolysable to the trichlorophenol, and expressed as prochloraz, in
    mature rapeseed treated in each of four sites in France ranged from
    0.06 to 0.2 mg/kg (over-all mean of 0.11 mg/kg). Treatment was with
    two applications of an E.C. formulation at a rate of 0.45 kg a.i./ha
    and harvest was 25-38 days after the last treatment. Mean residues of
    total prochloraz and its metabolites in hexane-extracted oil from
    these trials (omitting one individual 0.49 mg/kg outlier from six
    replicate results, otherwise ranging from 0.07-0.13 mg/kg) ranged from
    0.11 to 0.29 mg/kg (over-all mean 0.10 mg/kg), indicating a residue
    concentration factor of approximately 3 times. Residues in the treated
    seed and oil only ranged from approximately 1-3 times that in controls
    from any given site and were therefore not far removed from the limit
    of determination in any one site, with a variation of from 0.05 to 0.2
    mg/kg among the sites.

         In similar studies at three sites each in Denmark and Sweden, the
    concentration factor for prochloraz in the oil ranged from only 1.2 to
    2 times that in the seed. Treatment-to-harvest intervals range from 47
    to 76 days. In these studies, residues in treated seed and oil derived
    therefrom, although comparable to those in France, were significantly
    greater than in controls. The limit of determination was estimated at
    0.05 and 0.1 mg/kg, respectively, for seed and oil.

    Mushrooms - Mushrooms were harvested in France 17 days after 
    pre-emergence treatment with a 40 percent E.C. prochloraz formulation,
    administered at a rate of 40 g a.i./100 sq m. No information on good
    agricultural practice is available from France. The mushrooms were
    immediately processed by canning and dehydration, after which samples
    of canned mushrooms, the liquor and dehydrated mushrooms were analysed
    as total residues of prochloraz and its metabolites that were
    hydrolysable in the presence of pyridine hydrochloride to the
    trichlorophenol moiety. Total residues (apparently uncorrected for
    recoveries) and expressed as prochloraz were less than the 0.1 mg/kg
    limit of determination for canned mushrooms and the liquor, with
    control values of 0.03 and 0.05 mg/kg, respectively, reported. An
    apparent residue of 0.14 mg/kg in dehydrated mushrooms was less than

    the 0.23 mg/kg control value. Analytical recoveries were 64, 63 and 46
    percent, respectively, for dehydrated mushrooms, canned mushrooms and
    the liquor (Browne 1982h).

         In experiments conducted in The Netherlands, total residues of
    prochloraz and its metabolites, expressed as prochloraz, were
    determined in canned mushrooms and the liquor after three treatment
    schedules with a 50 percent W.P. formulation of the prochloraz
    manganese complex, (1) 0.75 a.i./sq m post-casing and 0.94 g a.i./sq m
    14 days after casing (2) 1.5 g a.i./sq m 9 days post casing (good
    agricultural practice in The Netherlands) and (3) 1.5 g a.i./sq m both
    at post-casing and after 14 days. Total residues expressed as
    prochloraz were equal to or less than the 0.1 mg/kg limit of
    determination in the six liquor samples and five of the six canned
    mushroom samples. For treatment (3) above, however, the residue was
    0.23 mg/kg in the sixth mushroom sample and 0.1 mg/kg in the control.
    No information was available on the interval from last treatment to
    harvest. Recoveries were 81 and 94 percent, respectively, for canned
    mushrooms and the liquor. No analyses were available for the
    unprocessed mushrooms (Churchill & Longland 1983c).

    Storage

    Citrus - Data are available from a variety of treatment and storage
    conditions and are summarized in Table 3. Navel oranges were
    commercially treated postharvest in South Africa with a 40 percent
    E.C. prochloraz formulation at 1 000 and 2 000 mg/kg a.i. rates then
    waxed and shipped by refrigerated vessel to the United Kingdom.
    Samples were stored either in the dark at approximately 20C or at
    4C. Sampling for analysis occurred at 0 (44 days after treatment), 7,
    14 and 21 days after storage commenced. Mean (range in parentheses)
    residues, corrected for recovery, of total prochloraz and metabolites
    expressed as prochloraz at the lower treatment rate were 0.05 mg/kg
    (0.030.08 mg/kg) in flesh, 2.1 mg/kg (1.4-2.8 mg/kg) in peel and 0.49
    mg/kg (0.3-0.7 mg/kg) on the whole fruit (calculated from peel to
    flesh weight ratios) for ambient and 4C fruit combined over the
    entire storage period. Corresponding values for the higher treatment
    rate were 0.05 mg/kg (0.02-0.07 mg/kg), 3.3 mg/kg (2.5-3.7 mg/kg) and
    0.84 mg/kg (0.7-1.7 mg/kg) respectively.

         The list of determination was reported as 0.05 mg/kg, which is
    consistent with uncontaminated control values of 0.01-0.02 mg/kg total
    residue. No observable trend in lower residues occurred during the 
    21-day storage period at either temperature and there were no
    noteworthy differences in residues between the storage temperatures.
    The trials also demonstrated that approximately 94 percent of the
    total residue was in the peel (Manley & Snowden 1982b).

         In similar postharvest treatments to oranges in Spain, with 
    0.05-0.1 percent solutions or 3-4 g a.i./tonne of fruit (usually in
    wax) with an E.C. formulation as a spray or dip, residues were
    determined after storage intervals typically ranging from 1-10 to 
    10-60 days at 4C-22C. Maximum peel residues were as much am 7.3
    mg/kg for prochloraz alone and 8.4 mg/kg for total residues of
    prochloraz and its metabolites, both expressed as prochloraz. Total
    residues in flesh, expressed as prochloraz, were 0.04-0.44 mg/kg and
    on a calculated whole fruit basis up to 2.5 mg/kg. As in the South
    African study, a definite trend towards decreased residues could not
    be determined over the varied storage intervals and temperatures and
    little difference was observed in residues where application rates
    varied by a factor of two. Peel was repeatedly shown to contain most
    of the total whole fruit residue with typically <5 percent being
    present in the flesh (Richards 1980b,f; Kelly 1980a; Browne 1981b).

         Similar studies were conducted in the United Kingdom where
    oranges were dip-treated with a 0.07 percent a.i., 40 percent E.C.
    formulation and analysed after 1, 7, 21, 25 and 70 days cold storage
    (temperature not provided). Total residues were expressed as
    prochloraz. Residues of the parent compound in peel ranged from 3.6 to
    5.1 mg/kg compared to 5.8 to 7.8 total residue. In flesh, the residues
    were 0.05 to 0.12 mg/kg and 0.07 to 0.15 mg/kg, respectively. No
    declining residue trend was observed over the 70-day maximum storage
    period, although total residues in flesh increased from about 4
    percent of the whole fruit residue at 1-7 days to 11 percent after 70
    days (Browne 1982i).

         No decline in residues on oranges was observed during storage at
    intervals from 1 to 16 days at ambient temperature in Australia after
    dip treatment with a 40 percent E.C. prochloraz formulation as a 250
    to 500 mg/kg a.i. solution. Total residues determined as the
    trichlorophenol expressed as prochloraz were similar from the two
    application rates, as were residues of prochloraz alone. Residues of
    prochloraz when determined alone ranged from 1.5 to 3.9 mg/kg (2.9
    mg/kg) in peel and from <0.02 to 0.1 mg/kg (0.04 mg/kg) in flesh over
    the 16-day storage interval for both concentrations. Total residues
    were similar 1.4-3.4 kg (2.5 mg/kg) and <0.05 mg/kg, respectively.
    Again, most of the residue was in the peel (Browne 1981a).

         Residues in Spanish lemons were investigated after a shower
    postharvest treatment with a 3 000 a.i. E.C. formulation in wax.
    Samples were analysed after 12 and 16 days of storage. The limit of
    determination was 0.02 mg/kg and 0.05 mg/kg for prochloraz alone and
    total residues expressed as prochloraz, respectively. Residues
    expressed as prochloraz were similar after both storage periods, with
    approximately 5 percent of the residue in the flesh. Residues of
    prochloraz alone and total residues were:

      Prochloraz alone (mg/kg)             Total residues (mg/kg)
                                                                     
    Peel         Flesh      Whole        Peel      Flesh       Whole*

    9.1-15.6     0.27-0.3   3.1-5.0      10.6      0.17-0.33   3.7-6
    (12.3 mean)  (0.29)     (4.6)        (14)      (0.23)      (5.1)

    *    Calculated from peel/flesh.

         Recoveries were 75 percent in peel and 77-100 percent in flesh 
         (Browne 1982c).

         In 1980, postharvest trials on oranges in Spain, using a 40
    percent E.C. prochloraz formulation, were made with 200 1 of wax
    formulation (3 g a.i./1 wax) to 150 tonnes of fruit (Richards 1980b).
    Samples of orange flesh from these trials were analysed for free
    2,4,6-trichlorophenol (BTS 45186), since no metabolism study was
    available on orange and BTS 45186 has been found in low levels in
    wheat (Kelly 1980d). Samples were analysed after 7 and 14 days at 
    20-22C.  Residues were 0.005-0.01 mg/kg (0.008 mg/kg mean) after 7
    days and 0.005 mg/kg after 14 days, as compared to <0.005 mg/kg for
    controls. Contrary to the findings in most other citrus postharvest
    trials, a slight trend of decreasing residues with time was indicated
    (Richards 1980e).

         In postharvest dip trials using a 25 percent E.C. or 25 percent
    W.P. prochloraz formulation on oranges and lemons in Italy residues
    were determined after 57 days storage at 7C. Significantly higher
    residues resulted from E.C. applications in both fruits and lemon
    residues were higher than those in oranges (Browne & Manley 1982b).

         Oranges treated in South Africa with a postharvest fungicidal
    brush at 500-4 000 mg/kg a.i. 45 percent E.C. were analysed after two
    months storage at ambient temperature. Again, most of the residue was
    in the peel, with total residues, expressed as prochloraz, ranging
    from 0.08 mg/kg at the lower application rate to 0.73 mg/kg at the
    higher one. There was a good correlation of residue level with
    application rate (Snowden & Manley 1983).

    Bananas - Bananas were treated by postharvest dipping in Australia
    with 250 and 500 mg/kg a.i. solutions of 40 percent E.C. prochloraz
    and analysed after ambient storage for 9, 10, 12 and 16 days. Free and
    conjugated residues of prochloraz and its metabolites were determined
    as the trichlorophenol, expressed as prochloraz, with a 0.05 mg/kg
    limit of determination. Residues resulting from both treatment rates
    and over the entire storage period ranged from 5.2-10 mg/kg in skin
    and 0.02-0.05 mg/kg in flesh. No evidence of decline in residues was
    observed in skin or flesh over the storage period and there was no
    significant difference in residues between the two application rates
    (Browne 1982b).

    Photodecomposition

         Thin-layer chromatography and nuclear magnetic resonance (NMR)
    analysis of a photodecomposition product of an aqueous solution of
    prochloraz confirmed the presence of 
    N-formyl-N-propyl-N',-2-(2,4,6-trichlorophenoxy) ethylurea (BTS 44596)
    (Haran 1978). Prochloraz aqueous solutions of 26.1 and 43.3 mg/kg
    concentrations in glass-stoppered flasks were exposed to artificial
    light (420-760 nm wavelength) at 32C for 36 and 16 days,
    respectively, with periodic analyses by high pressure liquid
    chromatography. At the lower concentration residues decreased from
    6.93  107 moles (26.1 mg/kg) initially to 1.94  107 moles after 36
    days while BTS 44596 increased from 0.0 to 3.58  107 moles. At the
    higher concentration, residues decreased from 11.5  107 moles (43.3
    mg/kg) at zero day to 5.8  107 moles after 16 days, while BTS 44596
    increased from 0.0 to 35.8  107 moles. The first order decay 
    half-lives were 20.5 and 18.1 days, respectively, for the two
    concentrations.

         Retention times indicated that a minor unquantified degradation
    product was N-propyl-N-2-(2,4,6-trichlorophenoxy) ethylurea (BTS
    44595). This appeared only towards the end of the exposure period
    (Haran 1980).

    METHODS OF RESIDUE ANALYSIS

         Analytical methods are available for the analysis of free
    prochloraz or total free and conjugated residues of prochloraz and its
    major metabolites. Methodology for free prochloraz was first developed
    for the analysis of cereal grains and straw (Somerville 1980). Finely
    milled straw or ground grain are vigorously extracted with acetone,
    filtered, a small portion acidified with HCl and concentrated by
    rotary evaporation. The aqueous fraction is partitioned with petroleum
    ether, which is discarded, adjusted to pH 6-7 and again partitioned
    with petroleum ether, which is concentrated to dryness. The sample is
    taken up in ethyl acetate and analysed by electron capture gas
    chromatography utilizing a 7 percent OV-101 packed column. Analytical
    recoveries of wheat and barley grain, amended with prochloraz at 
    0.05-0.5 mg/kg, were 78  10.6 percent and 91  10.9 percent,
    respectively. For straw, the respective recoveries were 82  12
    percent and 80.6  17 percent. The level of "sensitivity" has been
    estimated at 0.01 mg/kg for grain and straw, although in the field
    trials apparent untreated controls in cereal grain and straw were
    occasionally up to 0.02 mg/kg.

         With minor modifications, this method has been used for
    determining free prochloraz residues in apples, pears, citrus,
    mushrooms, strawberries and lettuce (FBC, (Hayto 1979b; Whiteoak 1981;
    Kelly 1980a; Browne 1981b, Maclaine Pont et al. 1980) with
    analytical recoveries of > 65 percent and usually > 80 percent.
    Apparent residues in untreated controls generally ranged from <0.01
    to approximately 0.05 mg/kg depending on the commodity.

         A method is also available for measuring total free and
    conjugated residues of prochloraz and its major plant metabolites, 
    N-formyl-N'-1-propyl-N'-[2-(2,4,6-trichlorophenoxy) ethyl] urea
    (BTS 44596), N-propyl-N-[2-(2,4,6-trichlorophenoxy) ethyl] urea
    (BTS 44595) and conjugated 2,4,6-trichlorophenol (BTS-45186), after
    converting all of them to the common moiety 2,4,6-trichlorophenol
    (Manley & Snowden 1982a). Any other metabolite containing the 
    2,4,6-trichlorophenol moiety would probably be measured as well.
    Although total residues are actually measured as BTS-45186, residues
    are usually expressed as prochloraz, after use of a molecular weight
    factor of 1.906.

         Thoroughly ground, milled, chopped or minced and mixed samples
    are Soxhlet extracted with acetone, filtered, dried by passing through
    anhydrous sodium sulphate and evaporated to near dryness by a rotary
    evaporator. The sample is refluxed with pyridine hydrochloride at
    205c for one hour to hydrolyse to the BTS-45186 moiety, after which
    HCl is added to the sample. The sample is liquid-liquid extracted
    after addition of petroleum ether. Potassium hydroxide is added, the
    sample partitioned and the aqueous phase collected and acidified with
    HCl. The sample is partitioned into toluene for analysis by 
    electron-capture gas chromatography, utilizing a 20 percent carobowax
    20M + 1.7 percent phosphoric acid packed column.

         The method was validated on fruits and cereal grains with mean
    over-all recoveries of 92  15.9 percent when samples were amended at
    0.2-10 mg/kg prochloraz. A 0.05 mg/kg limit of determination is
    considered attainable for most samples, although apparent residues of
    0.2-0.3 mg/kg may be encountered occasionally, especially in cereal
    straw.

         With minor variations, this method has been successfully used for
    the analysis of cereal grain and straw, cereal grain green plant
    tissues, apples, citrus fruit (peel, flesh, whole fruit), orange
    juice, rapeseed, rapeseed oil, mushrooms, stone fruit and assorted
    fruit with inedible peel (Kelly 1979b; Richards 1981a; Reary 1981a;
    Browne & Manley 1982a; Manley & Snowden 1982a). Specifics on
    individual crops under actual use conditions are considered earlier in
    this evaluation under "Residues Resulting From Supervised Trials" or
    under "Fate of Residues."

         An analytical method is also available for the determination of
    free BTS-45186, which may be a minor component of the residue (Kelly
    1980b; Richards 1980e).

         No analytical method suitable for enforcement purposes for
    products of animal origin was made available.

    NATIONAL MAXIMUM RESIDUE LIMITS REPORTED TO THE MEETING

    Country                     Commodity          MRL (mg/kg)

    France                      cereal grains      0.05 1
                                rape seed          0.05 2

    The Netherlands 3           Mushrooms          0.05
                                cereal grains      0.1
                                Milk               0.01
                                Meat               0.01
                                Other products     0 (0.01)

    German Federal Republic     Cereals            0.5 4

    1    Residues of prochloraz alone.

    2    Residues included not specified.

    3    For MRLs of The Netherlands, the residue is prochloraz
         and its metabolites, measured as 2,4,6-trichlorophenol
         and expressed as prochloraz. Residue on mushrooms and 
         for most cereal grain trials conducted in The 
         Netherlands were for total residues of prochloraz and 
         its major metabolites.

    4    A proposed 0.5 mg/kg NRL for prochloraz and metabolites 
         has been submitted.

    APPRAISAL

         Prochloraz is a fungicide in use and/or under development for
    control of fungal diseases on a variety of commodities in number of
    countries. It is used as a foliar spray, for post-harvest or seed
    treatments and is available in a variety of formulations for these
    uses, including a prochloraz-manganese complex wettable powder
    formulation for sensitive plant species.

         Residue data are available from field trials on a number of
    commodities in several countries, mostly from foliar applications to
    fruit and cereal grains, use in mushroom culture and postharvest
    applications to citrus and certain other fruit. Some residue data are
    also available for vegetables. Residues were determined either as
    2,4,6-trichlorophenol, prochloraz alone or prochloraz and its major
    metabolites, mostly the latter over-all. In select cases, data are
    available for both prochloraz alone and for prochloraz and its major
    metabolites. Apparently the earlier studies were for prochloraz alone,
    whereas in later studies total residues were emphasized. Data are
    insufficient and too variable to draw a general conclusion on the
    ratio of parent compound to parent plus metabolites. For example,
    there is little difference in residue measured for citrus or possibly
    for mushrooms, but for cereals residues appear to be substantially
    higher when total residues are determined.

         Residue trials on commodities for which there are known
    nationally approved or registered uses were available for watermelon,
    apple, grape, cereals, mushrooms and oil-seed rape. Therefore, only
    for these is consideration given for MRL estimates. However
    "recommended" were available for a number of other commodities and
    temporary limits are estimated for those with adequate data. Data were
    insufficient for estimation of maximum residue levels for sugarbeets,
    sugarbeet leaves, strawberries, almonds, almond hulls, lettuce,
    watermelon, apples, pears, rice and grapes.

         Information was available on the fate of residues in animals,
    plants, the environment and during storage and processing. In animals,
    prochloraz is rapidly metabolized from dermal or oral exposure. Most
    of the residue is rapidly excreted, with urinary excretion being the
    predominant route in most animals tested, although faeces is the
    predominant route in dogs. The principal metabolic products in the
    urine were 2,4,6-trichlorophenoxyacetic acid and 
    2,4,6-trichlorophenoxy-ethanol (mostly conjugated). The major plant
    metabolites have not been identified in the urine. Although residues
    were qualitatively similar in urine or in tissue distribution among
    animals studied, tissue residues have not been identified.

         The potential for residues in products of animal origin was
    investigated in two studies by feeding a lactating goat with 
    14C-phenyl-labelled prochloraz either by capsule or ad libitum with
    14C-prochloraz field-treated wheat straw. The first study represents
    the worst case maximum expected theoretical exposure from wheat straw
    and the straw feeding is probably more reflective of maximum exposure
    under normal feeding conditions.

         These goat metabolism/feeding studies give insight into the
    maximum potential for residues, although residues in animal tissues
    are not identified. It is not known whether urinary metabolites are
    the same as those in milk or tissues.

         Although straw was used as a worst-case for potential residues,
    foraging would appear to be potentially equally important, if not more
    so, if not label-restricted, since it can be fed at higher levels in
    the diet, as can citrus pulp. However, citrus uses presumably are
    intended where peel is discarded. Although wheat or barley grain
    residues were relatively low, grain may comprise up to 50 and 80
    percent of the diet of poultry and swine, respectively. No analytical
    method suitable for enforcement purposes for animal products is
    available, or at least known to be validated for that purpose.
    Additional information is needed to support a conclusion that the fate
    of residues in animals is adequately understood or to estimate maximum
    residue levels for products of animal origin.

         The fate of Prochloraz in plants was investigated in wheat
    (foliar, pre-emergence and seed treatments), citrus (postharvest),
    apples (foliar) and sugarbeet (soil uptake). In wheat plants, major
    residues at the vegetative stage from foliar treatment were free 
    BTS-44596, free and conjugated BTS-44595 and 2,4,6-trichlorophenol in
    decreasing order, which together accounted for 83 percent of the
    terminal residue after 19 days. Less than 2 percent was unchanged
    prochloraz and only 0.2 percent was 2,4,6-trichlorophenoxy acetic
    acid. No single unidentified residue accounted for more than 6.3
    percent of the remainder. Residues appear to be absorbed primarily
    within the first 24 hours.

         At the harvest stage, only the free trichlorophenol has been
    identified in straw or grain, and it occurs as 3-8 percent of the
    terminal residue. This, plus tritiated water and other presumably
    conjugated but unidentified residues containing the trichlorophenol
    moiety, account for 40-70 percent of the terminal residue. No single
    remaining unidentified residue fraction accounts for more than 6
    percent of the terminal residue.

         When applied to wheat seeds or as a pre-emergence drench, most
    residue was in or near the root system, with little upward mobility,
    and there is little evidence of upward mobility when prochloraz is
    applied to foliage although low levels translocate towards the roots.
    Only very low levels of residue were found in chaff and straw when
    wheat was grown in soil treated with radioactive 3H-prochloraz ten
    months earlier. However, sugarbeet seedlings showed low residues when
    planted as a rotational crop, but only trace levels were found in the
    foliage at maturity and no significant residue in the roots.

         In apples, residues migrated into the peel and by 33-63 days
    approximately 60-80 percent of the terminal or applied residue was in
    the peel, <2 percent on the surface and generally <7 percent of
    the applied dose in the flesh, although it can be twice as much.
    Qualitatively extractable peel residues were similar to residues found
    in wheat at the vegetative stage with approximately 80 percent of the
    residues hydrolysable to 2,4,6-trichlorophenol. This, therefore,
    accounts for approximately 50-60 percent of the total fruit residue.
    Other residues (primarily peel fiber-bound) were not identified, and
    although unresolved background accounted for approximately 10 percent
    of the whole fruit residue (14 percent of peel extractable), no one
    peel extractable metabolite or fraction exceeded approximately 5
    percent of the total fruit residues. The fate of residues in plants is
    reasonably well understood for the limited number and type of crops
    for which there are approved uses. If uses are expanded significantly
    to other food groups, additional metabolism studies would be prudent.

         Numerous experiments have been conducted on the fate of
    prochloraz residues in soil and water. Prochloraz is degraded under
    both aerobic and anaerobic conditions with formation of volatile
    compounds, probably CO2 and tritiated water. Residues remaining are
    predominantly prochloraz, BTS-44596 and BTS-45186, with binding to
    upper soil particles increasing with time. The half-life can range

    from 90-155 days, depending on conditions. Formation of volatiles is
    decreased under anaerobic conditions. Mobility is low in soils,
    although low mobility does occur under some conditions, especially for
    the metabolites in sand. Prochloraz is stable in water under acidic
    conditions, but does degrade under alkaline conditions.

         The fate of residues during processing was investigated for wheat
    made into bread, postharvest citrus, rapeseed oil and mushrooms after
    processing. Residues in bread made from wheat grain with <0.1 mg/kg
    prochloraz also showed <0.1 mg/kg residues. Since the limit of
    determination is 0.1 mg/kg, no conclusion could be made on the extent
    of residue concentration, if any. No information was available for
    residues in flour or other milling fractions. Similarly, low residues
    were found in malt from prochloraz-treated barley, but no information
    was available on the residue level in grain from which it was made.

         Residue levels concentrate from 1 to 3 times in oil processed
    from mature oilseed rape that has been field-treated with prochloraz.
    Residues in canned or dehydrated mushrooms or canning liquor after
    pre-emergence treatment with prochloraz were less than in untreated
    controls, except for one sample of canned mushrooms with a residue of
    0.23 mg/kg. No information was available on residue levels before
    canning or dehydration. No conclusion can be drawn on the extent of
    residue concentration, if any. When oranges treated postharvest were
    processed into "42 percent comminuted orange" or "whole orange
    juices", which are used to manufacture various orange drinks,
    approximately 70 percent of the residue in the oranges from which it
    was processed was lost.

         The fate of residues during storage after various postharvest
    prochloraz treatments was investigated for citrus, bananas and
    avocadoes. Except for one study where free 2,4,6-trichlorophenol was
    determined and where treated citrus was stored under a variety of
    conditions (dark or light, cold or room temperature and at intervals
    ranging from one to 70 days) total residues were very persistent, with
    little evidence of a decreasing trend over the varied treatment or
    storage conditions. Modest increases (2X) in application
    concentrations had little effect on residue levels, approximately 
    90-95 percent of which were in the peel. There was evidence of
    continued gradual translocation into the flesh as the interval from
    treatment increases, especially at room temperature. This was also
    found in studies on foliar treatments of mango. Residue levels during
    storage of prochloraz alone were similar to those for prochloraz and
    its major metabolites, suggesting little degradation or conjugation.
    Emulsifiable concentrate formulations gave significantly higher
    residues than wettable powder formulations and residues in lemons were
    higher than those in oranges.

         In bananas treated postharvest with prochloraz, no trend of
    decreasing residues was observed over a 16-day storage period at
    ambient temperature. Residue levels were similar with modest increases
    (2X) in treatment rate and, as in the case of citrus, most of the
    residue was in the peel.

         In avocadoes treated postharvest with prochloraz, residues were
    comparable to those from multiple foliar treatments. Approximately 
    10-30 percent of the residue could occur in the flesh after relatively
    short preharvest intervals. The translocation was therefore somewhat
    greater than in citrus, bananas and apples.

         Photodecomposition of an aqueous prochloraz solution resulted in
    the formation of plant metabolite BTS-44596 and towards the end of a
    36-day exposure to artificial light, a trace of plant metabolite 
    BTS-44595. A half-life of approximately 20 days was observed.

         Analytical methods are available for enforcement purposes for a
    wide variety of plant commodities. Residues of prochloraz alone or
    total residues of prochloraz and its major plant metabolites may be
    determined, although more of the field trials data were determined by
    the latter. Analytical recoveries were generally better than 70
    percent. No analytical methods have been validated for residues in
    animal products. The analytical methodology for the parent compound
    should be suitable and more appropriate for enforcement purposes and
    for estimating maximum residue levels (see Report of this Meeting,
    Section 2.3).

    RECOMMENDATIONS

         The Meeting examined residue data from supervised trials
    reflecting established or proposed good agricultural practice. From
    the data, the Meeting was able to estimate the maximum residue levels
    that are likely to occur when prochloraz is used in practice and when
    the reported intervals between last application and harvest or other
    restrictions are observed. Maximum residue limits are recommended
    where registered or approved uses are known and residues are
    determined as free prochloraz. Temporary maximum residue limits are
    recommended where only recommended uses are available or where total
    residues of prochloraz and its metabolites containing the 
    2,4,6-trichlorophenol moiety are determined. Regardless of the status
    of the ADI, these remain temporary pending receipt of information on
    approved or registered uses or data on supervised trials with residues
    determined as prochloraz.

         All estimates apply to foliar applications unless otherwise
    indicated.

                                                                                          

                         Estimated                      Interval from last
    Commodity            maximum residue                treatment to harvest (days)
                         limits (mg/kg)                 on which recommendation
                         Determined and expressed       is based and other
                         as prochloraz                  restrictions
                                                                                      

    Barley               0.05**                         40
    Oats                 0.05**                         40
    Rye                  0.05**                         40
    Wheat                0.05**                         40
    Barley straw         0.2                            40
    Oat straw            0.2                            40
    Rye straw            0.2                            40
    Wheat straw          0.2                            40
    Mushrooms            2                               2 3
    Citrus               5 (TMRL)1, 4                   postharvest

                         Sum of prochloraz
                         and metabolites expressed
                         as prochloraz 4
                                                     

    Bananas              5 (TMRL) 1                     postharvest
    Stone fruits         1 (TMRL) 1                     14
    Avocado              5 (TMRL) 1, 2                   7 (preharvest)
    Mango                2 (TMRL) 1, 2                  15 (preharvest)
    Papaya               1 (TMRL) 1                     postharvest
    Rapeseed             0.5 (TMRL)                     25
                                                                                      

    **   At or about the limit of determination.

    1    No information on approved or registered uses.
    2    Limit allows for cumulative residues from both preharvest and postharvest
         treatments, both of which are good agricultural practice.
    3    Limit accommodates applications after casing or after flushes, but not 
         direct treatment of mushrooms.
    4    Temporary regardless of the status of the ADI.
    
    FURTHER WORK OR INFORMATION

    Required (by 1985)

    1.   In order to establish MRLs for products of animal origin, several
         requirements remain:

         (a)  Metabolism studies in animals, including ruminants and
              poultry, at sufficiently high dosing levels to permit
              identification and quantification of tissue residues.

         (b)  If metabolism studies in (a) above indicate any possibility
              of residues in animal tissues, feeding trials should be
              conducted in animals, including ruminants and poultry, in
              which tissues are analysed for residues of concern
              identified in metabolism studies. Feeding in an appropriate
              number of animals should as nearly as possible reflect
              maximum levels of weathered residues likely to occur in
              practice and, ideally, at an exaggerated level.

         (c)  A validated analytical method suitable for enforcement
              purposes for products of animal origin.

    2.   Good agricultural practice information for those commodities for
         which temporary maximum residue limits are recommended,
         preferably for countries in which the residue trials were
         conducted or those in close proximity.

    3.   Additional data on residue trials reflecting good agricultural
         practice for commodities for which temporary maximum residue
         limits are recommended (except citrus). The additional data
         should be concurrently determined as both prochloraz and total
         residues of prochloraz and its metabolites containing the
         trichlorophenol moiety on the same samples. Sufficient data
         should be provided to permit further utilization of residue data
         already provided, therefore permitting recommendation of maximum
         residue limits expressed as prochloraz.

    Desirable

    1.   Additional national maximum residue limits.

    2.   Additional processing studies in cereals to permit a conclusion
         on the extent, if any, of residue concentration in milling
         fractions. Grain used should have residues sufficiently above the
         limit of determination for drawing conclusions.

    3.   Additional processing studies for mushrooms to permit a
         conclusion on the extent, if any, of residue concentration.
         Mushrooms should be analysed before and after processing.

    4.   Information on possible interference in prochloraz analysis in
         the presence of other pesticides, especially those containing the
         trichlorophenol moiety. If interferences are encountered,
         confirmatory analytical procedures for prochloraz and metabolites
         may be necessary.

    REFERENCES - RESIDUES

    Browne, P.M. Residues of prochloraz and major metabolites in oranges
    1981a     following postharvest dip treatment in Australia, 1981. FBC
              report RESID/81/72 submitted to FAO by FBC Ltd.
              (Unpublished)

    Browne, P.M. Residues of prochloraz and major metabolites in oranges
    1981b     following postharvest shower treatment in Spain, 1981. FBC
              report RESID/81/72 submitted to FAO by FBC Ltd.
              (Unpublished)

    Browne, P.M. Residues of prochloraz and major metabolites in avocados
    1982a     following postharvest dip treatment in Australia, 1981. FBC
              report RESID/82/2 submitted to FAO by FBC Ltd. (Unpublished)

    Browne, P.M. Residues of prochloraz and major metabolites in bananas
    1982b     following post-harvest dip treatment in Australia, 1981. FBC
              report RESID/82/7 submitted to FAO by FBC Ltd. (Unpublished)

    Browne, P.M. Residues of prochloraz and major metabolites in lemons
    1982c     following post-harvest shower treatment in Spain. FBC report
              RESID/82/8 submitted to FAO by FBC Ltd. (Unpublished)

    Browne, P.M. Residues of prochloraz and major metabolites in winter
    1982d     rye treated post-emergence with a 40% E.C. formulation in
              West Germany, 1981. FBC report RESID/82/25 submitted to FAO
              by FBC Ltd. (Unpublished)

    Browne, P.M. Residues of prochloraz and major metabolites in winter
    1982e     wheat treated postemergence with three applications of 40%
              E.C. formulation in Fed. Rep. Germany, 1981. FBC report
              RESID/82/29 submitted to FAO by FBC Ltd. (Unpublished)

    Browne, P.M. Residues of prochloraz and major metabolites in spring
    1982f     wheat and barley postemergence with a 40% E.C. formulation
              (two or three applications) in West Germany, 1981. FBC
              report RESID/82/31 submitted to FAO by FBC Ltd.
              (Unpublished)

    Browne, P.M. Residues of prochloraz and major metabolites in mushrooms
    1982g     following application of a 50 W formulation in Holland,
              1980. FBC report RESID/82/39 submitted to FAO by FBC Ltd.
              (Unpublished)

    Browne, P.M. Residues of prochloraz and major metabolites in processed
    1982h     mushrooms following application of a 40 E.C. formulation in
              France, 1981. FBC report RESID/82/68 submitted to FAO by FBC
              Ltd. (Unpublished)

    Browne, P.M. Residues of prochloraz and major metabolites in
    1982i     oranges following post-harvest dip treatment in the U.K.,
              1981. FBC report RESID/82/83 submitted to FAO by FBC Ltd.
              (Unpublished)

    Browne, P.M. & Manley, J.D. Analytical method for residues of
    1982a     prochloraz and major metabolites in orange juice. FBC report
              RESID/82/18 submitted to FAO by FBC Ltd. (Unpublished)

    Browne, P.M. & Manley, J.D. Residues of prochloraz and major
    1982b     metabolites in oranges and lemons following postharvest dip
              treatment in Italy, 1979. FBC report RESID/82/32 submitted
              to FAO by FBC Ltd. (Unpublished)

    Browne, P.M. & Manley, J.D. Residues of prochloraz and major
    1982c     metabolites in mangoes treated with a 50% W.P. formulation
              in Australia, 1981. FBC report RESID/82/34 submitted to FAO
              by FBC Ltd. (Unpublished)

    Campbell, J.K. Residues in milk and tissues of a goat dosed orally
    1980      with 14C-prochloraz. Boots report AX-80026 submitted to FAO
              by FBC Ltd. (Unpublished)

    Campbell, J.K. Residues of prochloraz in milk and tissues of a
    1983      lactating goat fed straw containing residues of radioactive
              prochloraz. FBC report METAB/83/8 submitted to FAO by FBC
              Ltd. (Unpublished)

    Campbell, J.K. & Needham, D. Residues in milk and tissues of a goat
    1980      dosed orally with 14C-BTS 44596 (major plant metabolite of
              prochloraz). Boots report AX-800333 submitted to FAO by FBC
              Ltd. (Unpublished)

    Churchill, J.H.M. & Longland, R.C. Residues of prochloraz and major
    1983a     metabolites in bananas following a single postharvest
              application with a 45% E.C. prochloraz formulation in South
              Africa, 1982. FBC report RESID/83/5 submitted to FAO by FBC
              Ltd. (Unpublished)

    Churchill, J.H.M. & Longland, R.C. Residues of prochloraz and major
    1983b     metabolites in avocadoes following application with a 45%
              E.C. formulation in South Africa. FBC report RESID/83/10
              submitted to FAO by FBC Ltd. (Unpublished)

    Churchill, J.H. & Longland, R.C. Residues of prochloraz and major
    1983c     metabolites in processed mushrooms following application
              with a 50% W.P. formulation of prochloraz-Mn complex in
              Holland, 1981. FBC report RESID/83/23 submitted to FAO by
              FBC Ltd. (Unpublished)

    Churchill, J.H.M. & Longland R.C. Residues of prochloraz and major
    1983d     metabolites in almonds following foliar application with a
              50% W.P. formulation in Israel, 1982. FBC report RESID/83/38
              submitted to FAO by FBC Ltd. (Unpublished)

    Churchill, J.H.M. & Longland, R.C. Residues of prochloraz and major
    1983e     metabolites in avocadoes following postharvest treatment
              with a 45% E.C. formulation in Australia, 1982/83. FBC
              report RESID/83/55 submitted to FAO by FBC Ltd.
              (Unpublished)

    Cron, J. Residues of prochloraz and major metabolites in rapeseed
    1982      following a single postemergence application with a 40 E.C.
              prochloraz and a prochloraz/carbendazim E.C. formulation in
              France 1980/81. FBC report RESID/82/74 submitted to FAO by
              FBC Ltd. (Unpublished)

    Cron, J.H. & Longland, R.C. Residues of prochloraz and major
    1983a     metabolites in avocadoes following multiple foliar
              application with a 50% W.P. formulation of prochloraz-Mn
              complex in Australia, 1981/82. FBC report RESID/82/120
              submitted to FAO by FBC Ltd. (Unpublished)

    Cron, J.H. & Longland, R.C. Residues of prochloraz and major
    1983b     metabolites in papayas treated postharvest with a 45% E.C.
              formulation in Australia, 1982. FBC report RESID/83/1
              submitted to FAO by FBC Ltd. (Unpublished)

    Douglas, M.T. & Pell, I.B. Assessment of the ready degradability of
    1982      prochloraz. HRC and FBC report METAB/82/44 submitted to FAO
              by FBC Ltd. (Unpublished)

    Douglas, M.T. & Pell, I.B. Assessment of biodegradability of
    1983      prochloraz by pre-adapted sewage organisms. HRC and FBC
              report METAB/83/10 submitted to FAO by FBC Ltd.
              (Unpublished)

    Goto, H. Residues of prochloraz in rice following seed soak or foliar
    1980      application with a 25% E.C. formulation in Japan, 1980.
              Inst. Environ. Toxicol., Japan, Nissan and FBC report
              submitted to FAO by FBC Ltd. (Unpublished)

    Haran, G. Identification of a photodecomposition product of BTS-40
    1978      542 (prochloraz). Boots report F-78014 submitted to FAO by
              FBC Ltd. (Unpublished)

    Haran, G. The effect of simulate& sunlight on aqueous solutions of
    1980      prochloraz. Boots report F-80010 submitted to FAO by FBC
              Ltd. (Unpublished)

    Hayto, E.M. BTS-40542 residues in wheat and barley. Boots report AX-
    1977a     77002 submitted to FAO by FBC Ltd. (Unpublished)

    Hayto, E.M. BTS-40 542 residues in wheat from Italy, 1977. Boots
    1977b     report AX-79003 submitted to FAO by FBC Ltd. (Unpublished)

    Hayto, E.M. BTS-40 542 residues in apples from Thurgarton, U.K. Boots
    1977c     report AX-77011 submitted to FAO by FBC Ltd. (Unpublished)

    Hayto, E.M. BTS-40542 residues in wheat from Holland, 1977. Boots
    1978a     report Ax-78006 submitted to FAO by FBC Ltd. (Unpublished)

    Hayto, E.M. BTS-40542 residues in wheat and barley from France, 1977.
    1978b     Boots report AX-78020 submitted to FAO by FBC Ltd.
              (Unpublished)

    Hayto, E.M. BTS-40542 residues in wheat and barley from the United
    1979a     Kingdom, 1977. Boots report AX-79001 submitted to FAO by FBC
              Ltd. (Unpublished)

    Hayto, E.M. BTS-40542 residues in apples from Thurgarton, U.K., 1977.
    1979b     Boots report AX-79005 submitted to FAO by FBC Ltd.
              (Unpublished)

    Hayto, E.M. BTS-40542 residues in cereals from Fed. Rep. Germany,
    1979c     1977. Boots report AX-79008 submitted to FAO by FBC Ltd.
              (Unpublished)

    Hayto, E.M. BTS-40542 and dicloran residues in lettuces from Holland,
    1979d     1978. Boots report AX-79010 submitted to FAO by FBC Ltd.
              (Unpublished)

    Heinanen, E. Investigation certification for residues of prochloraz in
    1983      spring wheat from Finland, 1982. VML report 2940, 2942/82
              submitted to FAO by FBC Ltd. (Unpublished)

    Housden, M.C. Residues of prochloraz and major metabolites in grain
    1982a     treated post-emergence with a 45% E.C. formulation in
              Belgium, 1981. FBC report RESID/82/1 submitted to FAO by FBC
              Ltd. (Unpublished)

    Housden, M.C. Residues of prochloraz and major metabolites in
    1982b     mushrooms following application of a 50W formulation in
              Australia, 1981/82. FBC report RESID/82/48 submitted to FAO
              by FBC Ltd. (Unpublished)

    Housden, M.C. Residues of prochloraz and major metabolites in cereals
    1982c     treated post-emergence with a 45% E.C. formulation (single
              or double application) in Denmark, 1982. FBC report
              RESID/82/111 submitted to FAO by FBC Ltd. (Unpublished)

    Housden, M.C. & Longland, R.C. Decline study of residues of prochloraz
    1983      and major metabolites in winter barley and wheat treated
              once with a prochloraz/carbendazim suspension concentrate
              formulation in Fed. Rep. Germany, 1982. FBC report
              RESID/83/19 submitted to FAO by FBC Ltd. (Unpublished)

    Housden, M.C. & Whiteoak, R.J. Residues of prochloraz and metabolites
    1982      in mushrooms following single and multiple applications
              (50w formulation) in the U.K. 1981 and 1982. FBC report
              RESID/82/63 submitted to FAO by FBC Ltd. (Unpublished)

    Kelly, I.D. BTS 40 542 residues in cereals from Austria, 1977. Boots
    1979a     report AX 79006 submitted to FAO by FBC Ltd. (Unpublished)

    Kelly, I.D. The analysis of free and conjugated residues of BTS 40
    1979b     542, BTS 44 596 and BTS 45 186 in grain. Boots report AX
              79007 submitted to FAO by FBC Ltd. (Unpublished)

    Kelly, I.D. The analysis of free and conjugated residues of prochloraz
    1979c     (BTS 40 542), BTS 44 595, BTS 44 596 and BTS 45 186 in wheat
              grain and straw from Fed. Rep. Germany, 1978. Boots report
              AX 79015 submitted to FAO by FBC Ltd. (Unpublished)

    Kelly, I.D. The analysis of free and conjugated residues of prochloraz
    1979d     (BTS 40 542), BTS 44 595, BTS 44 596 and BTS 45 186 in wheat
              grain and straw from Italy, 1978. Boots report AX 79017
              submitted to FAO by FBC Ltd. (Unpublished)

    Kelly, I.D. The analysis of free and conjugated residues of prochloraz
    1979e     (BTS 40 542), BTS 44 595, BTS 44596 and BTS 45 186 in wheat
              grain and straw from The Netherlands, 1978. Boots report AX
              79 017 submitted to FAO by FBC Ltd. (Unpublished)

    Kelly, I.D. The analysis of free and conjugated residues of prochloraz
    1979f     (BTS 40 542), BTS 44 595 and BTS 44 596 and conjugated
              residues of BTS 45 186 in cereal grain and straw from
              Austria, 1978. Boots report AX 79 020 submitted to FAO by
              FBC Ltd. (Unpublished)

    Kelly, I.D. The analysis of free and conjugated residues of prochloraz
    1979g     (BTS 40 542), BTS 44 595 and BTS 44 596 and conjugated
              residues of BTS 45 186 in wheat and barley grain from
              Denmark, 1978. Boots report AX 79021 submitted to FAO by FBC
              Ltd. (Unpublished)

    Kelly, I.D. The analysis of free and conjugated residues of prochloraz
    1979h     (BTS 40 542), BTS 44 595, BTS 44 596 and BTS 45 186 in wheat
              and barley grain and straw from France, 1978. Boots report
              AX 79023 submitted to FAO by FBC Ltd. (Unpublished)

    Kelly, I.D. Persistence and uptake of prochloraz in Spanish oranges
    1980a     following a post-harvest dip. Boots report AX 80003
              submitted to FAO by FBC Ltd. (Unpublished)

    Kelly, I.D. BTS 45 186 residues in prochloraz-treated wheat grain from
    1980b     France, 1977. Boots report AX 80010 submitted to FAO by FBC
              Ltd. (Unpublished)

    Kelly, I.D. The analysis of free and conjugated residues of prochloraz
    1980c     (BTS 40 542) and metabolites containing the 
              2,4,6-trichlorophenyl moiety in wheat grain and straw from
              The Netherlands, 1979. Boots report AX 80025 submitted to
              FAO by FBC Ltd. (Unpublished)

    Kelly, I.D. The metabolism of 3H-prochloraz in mature wheat grain and
    1980d     straw. Boots report AX 80028 submitted to FAO by FBC Ltd.
              (Unpublished)

    Kelly, I.D. The metabolism and distribution of BTS 46828 applied to
    1982a     the fruit of field-growing apples. FBC report METAB/82/18
              submitted to FAO by FBC Ltd. (Unpublished)

    Kelly, I.D. The hydrolysis of prochloraz in aqueous solution under
    1982b     acid, neutral and basic conditions. FBC report METAB/82/28
              submitted to FAO by FBC Ltd. (Unpublished)

    Kelly, I.D. & Krepski, W.J. The metabolism of prochloraz by wheat
    1980      grain and straw. Boots report AX 80009 submitted to FAO by
              FBC Ltd. (Unpublished)

    Kesterton, M.S. Distribution of radio-labelled residues in field soil
    1978      after application of 3H-BTS 40542. Boots report AX 78010
              submitted to FAO by FBC Ltd. (Unpublished)

    Kesterton, M.S. Report on the aerobic metabolism of prochloraz in
    1981a     soil over a period of 12 months. Boots report AX 81002
              submitted to FAO by FBC Ltd. (Unpublished)

    Kesterton, M.S. Report on the anaerobic metabolism of prochloraz in
    1981b     soil. Boots report AX 81004 submitted to FAO by FBC Ltd.
              (Unpublished)

    Kesterton, M.S. & Newby, S.E. A study of the leaching of prochloraz in
    1980a     soil. Boots report AX 80008 submitted to FAO by FBC Ltd.
              (Unpublished)

    Kesterton, M.S. & Newby, S.E. Adsorption and desorption studies of
    1980b     prochloraz in soil. Boots report AX 80012 submitted to FAO
              by FBC Ltd. (Unpublished)

    Kesterton, M.S. & Newby, S.E. Leaching study of prochloraz aged in a
    1981      silty clay loam soil. Boots report AX 81003 submitted to FAO
              by FBC Ltd. (Unpublished)

    Krepski, W.J. The uptake of 14C-prochloraz and 3H-prochloraz soil
    1981a     residues into wheat. Boots report AX 81001 submitted to FAO
              by FBC Ltd. (Unpublished)

    Krepski, W.J. The metabolism of 14C-prochloraz and 14C-BTS 46828 by
    1981b     apples grown under glass. Boots and FBC report submitted to
              FAO by FBC Ltd. (Unpublished)

    Krepski, W.J. Translocation of 14C-prochloraz applied as a liquid
    seed
    1982      dressing in wheat grown to maturity. FBC report METAB/81/30
              submitted to FAO by FBC Ltd. (Unpublished)

    Leake, C.R. & Lines, D. The leaching of prochloraz and its major
    1981      metabolites in four soil types using TLC. FBC report
              METAB/81/35 submitted to FAO by FBC Ltd. (Unpublished)

    Longland, R.C. Analysis of residues of prochloraz and major
    1983a     metabolites in grain and straw from Sweden following
              application of 45% E.C., 1982. FBC report RESID/82/114
              submitted to FAO by FBC Ltd. (Unpublished)

    Longland, R.C. Residues of prochloraz and major metabolites in
    1983b     sugarbeet following application of a 40% E.C. formulation in
              Italy, 1981. FBC report RESID/83/58 submitted to FAO by FBC
              Ltd. (Unpublished)

    Longland, R.C. & Churchill, J.H. Residues of prochloraz and major
    1983      metabolites in mangoes following foliar treatment with 50%
              W.P. and postharvest treatment with 40% E.C. formulations in
              Israel, 1982. FBC report RESID/83/7 submitted to FAO by FBC
              Ltd. (Unpublished)

    Maclaine Pont, M.A., Vogelzang, H.P. & Siegmann-Knoester, K.C. The
    1980      residue analysis of prochloraz in combination with dicloran.
              Asepta-fabrik and Boots report AX 80020/2 submitted to FAO
              by FBC Ltd. (Unpublished)

    Maier-Bode, H. The leaching of prochloraz in three standard soils from
    1980      Fed. Rep. Germany. HMB and FBC report submitted to FAO by
              FBC Ltd. (Unpublished)

    Manley, J.D. & Snowden, P.J. Analytical method for residues of
    1982a     prochloraz and major metabolites in miscellaneous fruit,
              cereal and vegetable crops (improved method). FBC report
              RESID/82/88 submitted to FAO by FBC Ltd. (Unpublished)

    Manley, J.D. & Snowden, P.J. Residues of prochloraz and major
    1982b     metabolites in oranges and processed oranges following
              commercial scale postharvest brush treatment with prochloraz
              (40 E.C.) in South Africa, 1982. FBC report RESID/82/89
              submitted to FAO by FBC Ltd. (Unpublished)

    Manley, J.D. & Snowden, P.J. Residues of prochloraz and major
    1982c     metabolites in rapeseed following treatment with a 40% E.C.
              formulation in the U.K., 1981/1982. FBC report RESID/82/90
              submitted to FAO by FBC Ltd. (Unpublished)

    McDougall, J. The metabolism of 3H-BTS 40 542 in wheat at a
    vegetative
    1979      growth stage. Boots report AX 79009 submitted to FAO by FBC
              Ltd. (Unpublished)

    McDougall, J. The uptake and translocation of 3H-prochloraz in wheat.
    1980a     Boots report AX 80007 submitted to FAO by FBC Ltd.
              (Unpublished)

    McDougall, J. The relative uptake and persistence of prochloraz and
    1980b     BTS 46 828 in apples following treatment with 14C-
              prochloraz and 14C-BTS 46 828. Boots report AX 80015
              submitted to FAO by FBC Ltd. (Unpublished)

    McGibbon, A.S. Uptake of prochloraz residues by sugarbeet from
    1982      prochloraz-treated soil under field conditions. FBC report
              METAB/82/27 submitted to FAO by FBC Ltd. (Unpublished)

    Newby, S.E. The laboratory decline of prochloraz in two soils, a sandy
    1982      loam and a silty clay loam, under sterile conditions. FBC
              report METAB/82/41 submitted to FAO by FBC Ltd.
              (Unpublished)

    Peatman, M.H. & Snowden, P.J. Residues of prochloraz and major
    1982      metabolites in rapeseed treated with the 40% E.C.
              formulation in France, 1982. FBC report RESID/82/116
              submitted to FAO by FBC Ltd. (Unpublished)

    Peatman, M.H. & Snowden, P.J. Residues of prochloraz and major
    1983      metabolites in rapeseed treated with a 45% E.C. formulation
              in Denmark and Sweden, 1982. FBC report RESID/83/29
              submitted to FAO by FBC Ltd. (Unpublished)

    Reary, J.B. Analytical method for free and conjugated residues of
    1981a     prochloraz, BTS 44595, BTS 44 596 and BTS 45 186 in cereals
              at different growth stages. FBC report RESID/81/13 submitted
              to FAO by FBC Ltd. (Unpublished)

    Reary, J.B. Residues of prochloraz and major metabolites in summer
    1981b     wheat treated post-emergence with a 40% E.C. formulation
              (two or three applications) in Fed. Rep. Germany, 1980. FBC
              report RESID/81/14 submitted to FAO by FBC Ltd.
              (Unpublished)

    Reary, J.B. Residues of prochloraz and major metabolites in cereals
    1981c     treated post-emergence with a 45% E.C. formulation in
              Holland, 1980. FBC report RESID/81/46 submitted to FAO by
              FBC Ltd. (Unpublished)

    Richards, M.E. The analysis of free and conjugated residues of
    1980a     prochloraz (BTS 40 542) BTS 44 595 and BTS 44 596 and
              conjugated residues of BTS 45 186 in wheat and barley,
              France, 1979. Boots report AX 80005 submitted to FAO by FBC
              Ltd. (Unpublished)

    Richards, M.E. The analysis of free and conjugated residues of
    1980b     prochloraz (BTS 40 542), BTS 44 595 and BTS 44 596 and
              conjugated residues of BTS 45 186 in Spanish oranges
              following a postharvest application, 1980. Boots report AX
              80021 submitted to FAO by FBC Ltd. (Unpublished)

    Richards, M.E. The analysis of free and conjugated residues of
    1980c     prochloraz (BTS 40 542), BTS 44 595, BTS 44 596 and
              conjugated residues of BTS 45 186 in wheat and barley, U.K.,
              1979. Boots report AX 80022 submitted to FAO by FBC Ltd.
              (Unpublished)

    Richards, M.E. The analysis of free and conjugated residues of
    1980d     prochloraz (BTS 40 542), BTS 44 595, BTS 44 596 and
              conjugated residues of BTS 45 186 in wheat and barley,
              Denmark, 1979. Boots report AX 80023 submitted to FAO by FBC
              Ltd (Unpublished)

    Richards, M.E. BTS 45 186 residues in oranges treated with prochloraz,
    1980e     Spain, 1980. Boots report AX 80027 submitted to FAO by FBC
              Ltd. (Unpublished)

    Richards, M.E. The analysis of free and conjugated residues of
    1980f     prochloraz, BTS 44 595 and BTS 44 596 and conjugated
              residues of BTS 45 186 in Spanish oranges following a
              postharvest application, 1980. Report No. 2. Boots report AX
              80030 submitted to FAO by FBC Ltd. (Unpublished)

    Richards, M.E. The analysis of free and conjugated residues of
    1980g     prochloraz, BTS 44 595 and BTS 44 596 and conjugated
              residues of BTS 45 186 in winter wheat, Fed. Rep. Germany,
              1979. Boots report AX 80032 submitted to FAO by FBC Ltd.
              (Unpublished)

    Richards, M.E. The analysis of free and conjugated residues of
    1981a     prochloraz, BTS 44 595 and BTS 44596 and conjugated residues
              of BTS 45 186 in grain and straw. Boots and FBC report AX
              800 35 submitted to FAO by FBC Ltd. (Unpublished)

    Richards, M.E. The analysis of free and conjugated residues of
    1981b     prochloraz, BTS 44 595 and BTS 44 596 and conjugated
              residues of BTS 45 186 in winter barley, Fed. Rep. Germany,
              1980. Boots and FBC report AX 81005 submitted to FAO by FBC
              Ltd. (Unpublished)

    Richards, M.E. The analysis of free and conjugated residues of
    1981c     prochloraz, BTS 44 595 and BTS 44 596 and conjugated
              residues of BTS 45 186 in mushrooms, U.K., 1980. FBC report
              METAB/81/17 submitted to FAO by FBC Ltd. (Unpublished)

    Snowden, P.J. Residues of prochloraz and major metabolites in stone
    1983      fruit following foliar applications of prochloraz (50 E. and
              40 E.C.) in Europe (1982) and South Africa (1981/2 and
              1982/3). FBC report RESID/83/57 submitted to FAO by FBC Ltd.
              (Unpublished)

    Snowden, P.J. & Manley, J.D. Residues of prochloraz and major
    1983      metabolites in Tambors oranges following commercial scale
              postharvest brush treatment with prochloraz (45% E.C.) in
              South Africa, 1982. FBC report RESID/83/9 submitted to FAO
              by FBC Ltd. (Unpublished)

    Somerville, L. The analysis of prochloraz residues in cereals. Boots
    1980      report AX 80020/1 submitted to FAO by FBC Ltd. (Unpublished)

    Stockbauer, I. Leaching of Sportak PF (prochloraz and carbendazim) in
    1983      German soils. ASU and FBC report submitted to FAO by FBC
              Ltd. (Unpublished)

    Wang, S.S. Residues of prochloraz in grapes, apples and watermelon
    1982      following foliar application with a 25% E.C. formulation in
              Taiwan, Taiwan Plant Protection Centre report submitted to
              FAO by FBC Ltd. (Unpublished)

    Whiteoak, R.J. Residues of prochloraz in mushrooms following multiple
    1981      applications of a 50% W.P. formulation in the U.K., 1980/81
              (ADAS trial results), FBC report RESID/81/41 submitted to
              FAO by FBC Ltd. (Unpublished)

    Whiting, K.C. & Dickinson, W. The stability of the manganese complex
    1979      of prochloraz in water. Boots report F 79005 submitted to
              FAO by FBC Ltd. (Unpublished)


    See Also:
       Toxicological Abbreviations
       Prochloraz (JMPR Evaluations 2001 Part II Toxicological)