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WORLD HEALTH ORGANIZATION |
WHO/PCS/DS/96.94 |
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ORGANISATION MONDIALE DE LA SANTE |
Original: ENGLISH |
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FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS |
Distr.: LIMITED |
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ORGANISATION DES NATIONS UNIES POUR L'ALIMENTATION ET L'AGRICULTURE |
Date of issue: July 1996 |
WHO/FAO DATA SHEETS ON PESTICIDES
No. 94
It must be noted that the issue of a Data Sheet for a particular pesticide does not imply endorsement of the pesticide by WHO or FAO for any particular use, or exclude its use for other purposes not stated. While the information provided is believed to be accurate according to data available at the time when the sheet was compiled, neither WHO nor FAO are responsible for any errors or omissions, or any consequences therefrom.
The issue of this document does not constitute formal publication. It should not be reviewed, abstracted or quoted without the agreement of the Food and Agriculture Organization of the United Nations or of the World Health Organization.
Ce document ne constitue pas une publication. Il ne doit faire l'objet d'aucun compte rendu ou résumé ni d'aucune citation sans l'autorisation de l'Organisation des Nations Unies pour l'Alimentation et l'Agriculture ou de l'Organisation Mondiale de la Santé.
CLASSIFICATION:
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Primary use: |
Fungicide |
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Secondary use: |
None |
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Chemical group: |
Ethylenebisdithiocarbamates |
These three fungicides are metallo co-ordination complexes with ethylenebis (dithiocarbamate), and exist as polymers. The manganese zinc coordination complexes are known as maneb and zineb, respectively. Mancozeb is a coordination complex with both zinc and manganese, and has fungicidal activity distinct from either maneb or zineb.
maneb (BSI, E-ISO, JMAF); manèbe (F-ISO).
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IUPAC: |
Manganese ethylenebis (dithiocarbamate) (polymeric). |
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CAS: |
[[1,2-ethanediylbis[carbamodithioato]](2-)]manganese. |
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CAS Reg. No.: |
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Molecular formula: |
(C4H6MnN2S4)x |
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Relative molecular mass: |
(265.3)x |
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Structural formula: |
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DithaneRM-22; Fungiman 35R; Griffin Manex, KypmanR; Lonocol M; ManebaR; Manesan; Manex; ManzateR; MEB, NesporR; Polyram-MR; Remasan; SopranebeR; TesanR-LSR; TrimangolR; TubothaneR; ENT 14875.
zineb (BSI, E-ISO, JMAF); zinèbe (F-ISO); exception The Federal Republic of Germany.
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IUPAC name: |
Zinc ethylenebis (dithiocarbamate) (polymeric). |
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CA name: |
[[1,2-ethanediylbis[carbamodithioato]](2-] zinc. |
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CAS Reg. No.: |
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Molecular formula: |
(C4H6N2S4Zn)x |
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Relative molecular mass: |
(275.8)x |
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Structural formula: |
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Aspor; Devizeb; DipherR; DithaneRZ-78; Ditiozin; Enozin; HexathaneR; KypzinR; LonacolR; ParzateR-C; Phytox; Polyram-ZR; Pomarsol-Z; Sperlox-Z; TiezeneR; TritoftorolR; ZebtoxR; ZimateR; ZinosanR; ENT 14874.
mancozeb (SBI, E-ISO), mancozèbe (F-ISO)
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IUPAC name: |
Manganese ethylenebis (dithiocarbamate) (polymeric) complex with zinc salt: |
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CA name: |
[[1,2-ethanediylbis[carbamodithioato]](2-)] manganese mixture with [[1,2-ethanediylbis[carbamodithioato]](2-)] zinc. |
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CAS Reg. No.: |
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Molecular formula: |
(C4H6MnN2S4) x (C4H6N2S4Zn) |
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Molecular weight: |
A coordination complex of maneb and zinc. |
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Structural formula: |
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DithaneRM-45; Fore; Mancofol; ManzateR; 200; Manzeb;
Manzin-80R; Nemispor, PenncozebR; Policar-MZR; Policar S; Vondozeb PlusR; Ziman-DithaneR.
Maneb, zineb and mancozeb are ethylenebis (dithiocarbamate) fungicides. Each provides a distinct spectrum of action and of crop tolerance. They are of low acute toxicity but may cause sensitization in susceptible individuals. Studies in rats demonstrate that these fungicides may cause foetal malformations after a single oral exposure to high doses which also cause maternal toxicity. The breakdown products of residues on crops may be more toxic than the parent compound itself. Alcohol is contraindicated following exposure to dithiocarbamates.
Ethylenethiourea (ETU) is a contaminant, metabolite and breakdown product of ethylenebis(dithiocarbamates). ETU may be gastrogenic, teratogenic and oncogenic in the rat. The ETU concentration may increase during cooking of food containing maneb, zineb or mancozeb residues.
Maneb, zineb and mancozeb are solids, described as yellow, light-beige and yellow in colour, respectively. All three fungicides decompose before melting and none are corrosive in the dry state. Zineb is corrosive to iron and copper in the presence of moisture.
The three fungicides have slight water solubility and are practically insoluble in most organic solvents. Zineb is slightly soluble in pyridine.
Not stable in acids. Maneb and zineb lose activity on prolonged exposure to air, heat and moisture. Mancozeb is slowly decomposed by heat and moisture but is stable under normal dry storage conditions. Inadequate storage conditions may cause evolution of a flammable gas.
Negligible.
Available as dusts, wettable powders, paste, liquid flowable and flowable suspensions. May be formulated with copper and other fungicides.
Used to control numerous foliar blights, rot, mildew, molds and rusts. Dust and spray treatments are used to control fungi and molds on seeds.
Used as a foliar application, seed treatment and soil drench. May be used on appearance of the pest. Treatment should be repeated as necessary and according to manufacturers' recommendations. Mancozeb may be used as a protective fungicide.
Some phytoxicity may be observed, especially on young plants. Phytotoxicity has been cited for cherries, apples, cucurbits, pears and tobacco. The three fungicides differ in their phytotoxic effect and manufacturers' guidelines should be closely followed.
No recommended usage reported.
Maneb, zineb and mancozeb are poorly absorbed from the gastrointestinal tract. They may also be absorbed following dermal contact or following inhalation of dusts or fine spray.
Studies in rats with 54Mn-labelled maneb have indicated that the metal moiety of the complex is removed before absorption from the gastrointestinal tract. The extent of absorption of the ethylenebisdithiocarbamates may be influenced by the presence of metal cations. The amount appearing in the urine may be influenced by the extent of polymerization in the sample administered.
In rats, urinary excretion accounted for about 50% of an oral dose of maneb and was independent of the magnitude of dose. In the mouse, urinary excretion of a single dose of maneb or zineb was 10%. In either species metabolism to CO2 was minimal. Excretion was rapid and essentially complete within 72 hours.
Urinary metabolites identified in rat included ethylene-bis-isothiocyanate sulfide, ethylene thiourea, ethylene urea, conjugated and unconjugated ethylenediamine. Naturally occurring metabolic products such as glycine and oxalic acid were found in the urine of cows.
MANEB
Toxicity, single dose
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Oral LD50 |
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Rat |
6750 mg/kg b.w.* |
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Rat (M,F) |
>8000 mg a.i./kg b.w. (Manzate DR in carboxymethyl cellusolve) |
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Mouse (M,F) |
>8000 mg a.i./kg b.w. (Manzate DR in carboxymethyl cellusolve) |
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Mouse |
4000 mg/kg b.w. (technical material) |
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Guinea pig |
7500 mg/kg b.w. |
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Dermal LD50 |
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Rat |
>5000 mg/kg b.w. |
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Rabbit |
>5000 mg/kg b.w. |
In rats, deaths usually occurred 1-2 daysafter exposure to lethal concentrations of maneb. Poisoned rats showed ataxia, hyperactivity followed by inactivity, loss of muscle tone and alopecia.
Primary irritation:
Maneb, zineb or mancozeb produced erythema of shaved guinea pig skin following a 24 hour occluded application of 5% solution.
Toxicity, repeated doses:
Six male rats receiving oral doses of 1500 mg/kg b.w./day for 10 days showed weight loss and weakness of the hind limbs. One rat died after eight doses.
Oral administration of 100 or 500 mg/kg b.w./day to rats for four months induced proliferative changes in the epithelium of the thyroid and hepatotoxicity. No central nervous system changes were observed.
Dermal sensitization: Maneb, zineb and mancozeb were potent dermal sensitizers to guinea pig. Cross-sensitization between the three was observed.
Dietary studies
Dogs receiving maneb in the diet at concentrations equivalent to 20 mg/kg b.w./day for up to one year showed symptoms of general malaise accompanied by neuromuscular disturbances in the hind limbs. At concentrations equivalent to 200 mg/kg b.w./day these symptoms progressed to flaccid paraplegia and moribund dogs were observed at 3-7 months. Post-mortem examination revealed damage to the spinal cord, peripheral nerves and muscles of dogs receiving 200 mg/kg b.w./day. Impairment of renal function was observed at doses equivalent to 75 or 200 mg/kg b.w./day. No adverse effect was observed at 2 mg/kg b.w./day. Evidence of disturbances in thyroxine and iodine storage or metabolism was observed in rats receiving 150 mg/kg diet for 90 days.
Teratogenicity
Maternal toxicity was observed in Sprague Dawley rats receiving oral doses of 96%, pure maneb at 46.4 mg/kg b.w./day, from 7 to 28 days of age, based on day 7 body weight. Dosing was then continued at 158 mg/kg diet up to 78 weeks of age. No increase in tumour formation was observed in either strain.
Maternal toxicity was observed in Sprague Dawley rats receiving oral doses of 96, 192 or 384 mg a.i/kg b.w. day (as Dithane M-22) on gestation days 7-16. Only the offspring of the highest dose group were adversely affected. In this group a decreased foetal weight, growth retardation, reduced caudal ossification and hydrocephalus were observed. Mice receiving the same formulation at oral doses of 300, 600 or 1200 mg a.i./kg day on gestation days 7 to 16 showed also teratogenic effects. Dose related increases in maternal relative liver weight and decreases in foetal caudal ossification were observed. Other reports have also shown that maneb is teratogenic in rats but not in mice. A single dose of 400 or 700 mg/kg b.w./day (as Fungiman 35) administered to Sprague Dawley rats on day 11 resulted in a 46% and 100% malformation rate, respectively. Both doses increased the resorption rate. At the lower dose visceral malformations and shortening of the tail were apparent. At 700 mg/kg b.w. severe limb and craniofacial malformations were also present.
A single oral dose of 1420 mg/kg b.w. given to NMRI mice on day 9 or 13 of gestation was without adverse maternal of foetal effect.
Reproduction
No adverse effects were observed in ChR-CD rats during a three generation reproduction study, following administration of 125 or 250 mg/kg diet (as Manzate DR). Reversible, reduced fertility has been reported in male and female rats at oral doses 10 mg/kg b.w./day but the published data available do not allow adequate interpretation of these reports.
Mutagenicity
No mutagenic effect was observed, with or without metabolic activation, in Escherichia coli WP2 hcr or in several strains of Salmonella typhimurium. An increased incidence of chromosomal aberrations was observed in vitro following metabolic activation during incubation with a mammalian cell line.
Neurotoxicity
Ataxia and paralysis were observed in male and female CD rats receiving oral doses of 300 or 600 mg/kg b.w./day on day 33 (post natal) to day 90. Female rats were affected at an earlier age than the males and more females were affected. Rats showing ataxia were removed from the treatment. The peripheral neuropathy was reversible, irrespective of whether the ataxia had progressed to paralysis or not. No adverse effects were observed following administration of 600 mg/kg b.w. /dy on post partum days 21-30. Ataxia was observed following acute intoxication (see Section 2.1.4).
TOXICOLOGY - MAN
Absorption route: No published information available but animal studies show that these dithiocarbamates may be absorbed from the gastrointestinal tract. Absorption from the skin or lungs may also be possible.
Dangerous doses: No published information available.
Observations of occupationally exposed workers: A worker handled an entire 250 g package of maneb without gloves. The worker reported applying two spray treatments, re-entering the crop area and eating a small amount of treated corn 24 hours after spraying. During hospitalization an exanthema developed. Full recovery was reported.
Observations on exposure to the general public: Incidences of dermatitis have been reported following exposure to plants previously treated with maneb or mancozeb.
Observations on volunteers: Patch-tests on three volunteers who had reported adverse effects from treated plants, demonstrated that maneb was a dermal sensitizer. A variable cross sensitization was observed to ammonium and sodium dithiocarbamates. None of the volunteers showed a cross sensitization to zineb.
Reported mishaps: An accident which soaked the back of a woman with a maneb solution is reported to have led to renal failure and exanthema. The woman made a full recovery.
TOXICITY - NON-MAMMALIAN
Fish - formulated product
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48 hour exposure |
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Harlequin fish |
0.77 mg/L (as TrimangolR, 80% maneb) |
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96 hour exposure |
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Harlequin fish |
0.53 mg/L |
(as TrimangolR) |
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Bluegill |
0.9 - 1.00 mg/L |
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Birds
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LC50 |
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Mallard duck |
>10,000 mg/kg diet |
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Bobwhite quail |
>10,000 mg/kg diet |
MANCOZEB
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Toxicity, single dose |
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Oral LD50 |
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Rat |
> 8000 mg/kg bw.* |
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Rat |
> 12000 mg/kg b.w. |
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Dermal LD50: |
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Rat |
> 10000 mg/kg b.w. |
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Rabbitt |
> 5000 mg/kg b.w. |
Primary irritation:
Mancozeb, maneb and zineb produced erythema of shaved guinea pig skin following a 24 hour occluded application of 5% solution.
Toxicity, repeated doses:
No published information available other than effects observed during gestation (see Section 2.1.7).
Dermal sensitization: Mancozeb was a potent dermal sensitizer in guinea pig. Cross-sensitization was obserbed between mancozeb, zineb and maneb.
No adverse effects were observed in rats following a two year administration of 250 mg/kg diet. A depression of growth and an increase in the relative liver weights were observed at 1250 and 2500 mg/kg diet. The latter dose also gave an incidence of impaired food intake, mortality, nodular goitre and thyroid hyperplasia.
Teratogenicity
Sprague Dawley rats receiving an oral dose of 1320 mg/kg b.w. (as DeZata M-45) on gestation day 11, showed an increased incidence of visceral malformations in the foetus. Hydrocephaly and malformations of the spine were also apparent. The foetuses of five litters examined following administration of 730 mg/kg b.w. showed no malformations other than one foetus with dilation of the renal pelvises and a 14% incidence of superficial haemorrhage. No teratogenic effect was observed in NMRI mice receiving 1320 mg/kg b.w. as a single oral dose on gestation day 9 or 13.
Reproduction
Reduced fertility was observed in the first and second generations following administration of 1000 mg/kg diet in a three generation study. No effect was observed on gestation, lactation, viability of offspring or weaning weight. No adverse organ histopathology was observed in any generation. Doses of 25 or 100 mg/kg diet were without adverse effect.
Mutagenicity
No mutagenic activity was observed, with or without metabolic activation E. coli WP2 hcr or in several strains of S. typhimurium. A dose related incidence of chromatid-type aberrations was observed in the bone marrow of Wistar rats following a single intraperitoneal dose of 2.5 or 5 mg/kg b.w. Dietary administration of 200 mg/kg diet to Wistar rats for 280 days produced an increase in the number of observed bone marrow cell aberrations.
Neurotoxicity
No published information available.
TOXICOLOGY - MAN
Absorption route: No published information available but animal studies show that these dithiocarbamates may be absorbed from the gastrointestinal tract. Absorption from the skin or lungs may also be possible.
Dangerous doses: No published information available.
Observations of occupationally exposed workers: A worker was hospitalized following spraying with mancozeb and subsequent re-entry into the treated area. Weakness, headache, nausea, fatigue and tonic-clonic convulsions were reported. Reversible alterations in the electroencephalogram were also observed. Symptomatic treatment aided a full recovery. This incident followed a previous exposure to a more dilute formulation which caused milder symptoms. The worker had no previous adverse medical history.
No product-related thyroid dysfunction or health related problems were seen in a population of workers involved in the manufacture of mancozeb; no thyroid cancer was seen in 1929 ethylenethiourea production workers and a later occupational study revealed no thyroid dysfunction among workers exposed to ethylenebisdithiourea or to a dithiocarbamate commonly used in rubber production.
Observations on exposure to the general public: Incidences of dermatitis have been reported following exposure to plants previously treated with mancozeb.
Reported mishaps: A widespread dermatitis was reported by a woman following storage of mancozeb powder in a garage.
TOXICITY - NON-MAMMALIAN
Fish - formulated product
48 hour exposure
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Harlequin fish |
4.0 mg/L (as Dithane 945R, 80% mancozeb) |
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Carp |
24 mg/L (as Novozir MN 80, 80% mancozeb) |
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Rainbow trout |
1.85 mg/L (as Novozir MN 80, 80% mancozeb) |
96 hour exposure
No data available.
Birds
No data available.
ZINEB
Toxicity - single dose
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Oral LD50 |
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Rat |
>5200 mg/kg b.w.* |
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Rat (M,F) |
8200 - 8900 mg/kg b.w. (Zineb 75-WPR in carboxymethyl cellusolve). |
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Mouse (M,F) |
7600 - 7700 mg/kg b.w. (Zineb 75 WPR in carboxymethyl cellusolve) |
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Guinea pig |
>4800 mg/kg b.w. |
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Rabbit |
>600 mg/kg b.w. |
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Dermal LD50 |
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Rat |
>10,000 mg/kg b.w. |
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Subcutaneous LD50: |
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Rat(M) |
> 5600 mg/kg b.w. |
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Intraperitoneal LD50: |
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Mouse (M) |
2400 mg/kg b.w. |
Deaths usually occurred 1-2 days after exposure of rats to lethal concentrations of zineb. Poisoned rats showed ataxia, hyperactivity followed by inactivity, loss of muscle tone and alopecia.
Primary irritation:
Zineb produced erythema of shaved guinea pig skin following a 24 hour occluded application of 5% solution.
Mild irritation of rabbit eyes was observed following installation of the wettable powder. No irritation was observed when a suspension of the powder was used.
Toxicity, repeated doses:
No adverse effects were observed in rats receiving oral dose of 250 mg/kg bw. day, five days a week for four weeks. A dose of 100 mg/kg b.w./day resulted in enlarged kidneys, without histopathological changes in both sexes. At this dose, thyroid hyperplasia was observed in the females. This effect was reversed within two weeks of cessation of exposure.
Thyroid hyperplasia has also been observed in male rats receiving oral doses of 1000 mg/kg b.w./day for 30 days. in these rats increased absolute and relative pituitary weight and degeneration of seminiferous tubules of the testes were also noted.
In rats, oral administration of 1000 or 2000 mg/kg b.w./day (as Dithane Z-78 in corn oil) for 14 days caused decreased body weight but did not affect food intake. The same doses, administered for 11 days, were without adverse effects in mice.
Bodyweight, haematology and mortality were unaffected in dogs receiving 10,000 mg/kg diet for one year. Thyroid hyperplasia was apparent at 10,000 mg/kg diet. In rats, an increased thyroid weight was observed at doses of 500 - 10,000 mg/kg diet for thirty days. However, only at 10,000 mg/kg diet were these changes accompanied by hyperplasia which was evident in 3/10 rats examined.
Interpretation of a two year feeding study involving 10,000 mg/kg diets was complicated by the small number of rats used. Thyroid hyperplasia observed was increased at 1000 mg/kg diet and the severity of the response was dose dependent. No adverse effect on haematological parameters was observed.
Two strains of mice received gavage doses of 97% pure zineb at 464 mg/kg b.w./day, from 7 to 28 days of age, based on body weight at day 7. Dosing was then continued up to 1298 mg/kg diet up to 78 weeks of age. No increase in tumour formation was observed in either strain.
No increased tumour incidence was observed in a small number of rats receiving up to 10,000 mg/kg diet for two years.
Teratogenicity
Hydrocephalus and skeletal abnormalities were observed in the offspring of CD rats receiving 2000 mg Dithane Z at 78 kg b.w. /day on gestation days 6-19. Foetal and maternal body weights were also reduced but there was no increase in foetal mortality. Doses of 632 mg Dithane Z-78 kg b.w./day were without affect on the foetus or dam.
No teratogenic effects were seen in CD-1 mice receiving 2000 mg Dithane Z at 78 b.w. day on gestation days 6-16. At the top dose, the concentration of the contaminant ethylene thiourea in this formulation was within the range of that known to induce neural tube defects in rats.
Reproduction
Reduced fertility is reported following oral administration to male or female rats, but inadequate published data preclude evaluation of these studies.
Mutagenicity
No mutagenic activity was observed, with or without metabolic activation, in E. coli WP2 hcr or in several strains of S. typhimurium.
Zineb was mutagenic and caused DNA damage in Bacillus subtilis without metabolic activation. Metabolic activation reduced the response.
Neurotoxicity
Ataxia was observed following a single oral administration to rats (see Section 2.1.4).
TOXICOLOGY - MAN
Absorption route: No published information available but animal studies show that these dithiocarbamates may be absorbed from the gastrointestinal tract. Absorption from the skin or lungs may also be possible.
Dangerous doses: No published information available.
Observations of occupationally exposed workers: Examination of lymphocytes from workers involved in zineb manufacture showed an increased incidence of chromosomal breaks.
The degree of abnormality was correlated to the air concentrations of zineb in each work area but not to duration of exposure. Air concentration of zineb exceeded recommended maxima in some instances.
Contact dermatitis has been reported in field workers using zineb formulations.
Observations on exposure to the general public: No data available.
Observations of volunteers: No data available.
Reported mishaps: No data available.
TOXICITY - NON MAMMALIAN
Fish - formulated product
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48 hour exposure |
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Harlequin fish |
400 mg/L (70% zineb) |
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96 hour exposure |
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Harlequin fish |
250 mg/L |
(70% zineb) |
Birds
Administration of maneb or zineb 600 mg/kg diet for seven days was without adverse effect on egg production in domestic hens.
Maneb, Zineb and Mancozeb
(For definitions of categories see "Introduction to data sheets").
All formulations - Category 5
All formulations: Should be transported and stored in clearly labelled leakproof containers, secure from access by children and well away from food and feedstuffs. A loss of fungicidal activity and formation of flammable vapours may result on exposure of these formulations to moisture or heat. Store in a cool, dry place. Ensure that air can circulate around the storage containers.
All formulations: Adequate protective clothing (see Section 4.1.3) should be worn at all times to prevent skin, respiratory tract and eye contact with these irritant fungicides. Adequate washing facilities should be provided close to the site of handling. Hands and exposed skin should be thoroughly washed with soap and water after handling. Smoking, eating and drinking should be prohibited during handling and before washing after handling.
All formulations: Decontamination of containers for re-use should not be permitted. Empty containers should be burned or buried in a deep pit, well away from water sources. Keep away from the smoke during burning.
All formulations: Account should be taken of the workers' ability to comprehend and follow instructions. Workers with a history of sensitization to dithiocarbamates should be excluded from contact. Workers should be instructed in techniques to minimize contact.
All formulations: Pilots and loaders should have specialized training in application methods and in the recognition of the early symptoms of pesticide poisoning. A suitable respirator should be worn in addition to overalls and impermeable gloves. Flagmen should wear impermeable gloves, boots, overalls and a broad-brimmed hat and should be located well away from the dropping zone.
All formulations - Minimum cautionary statement
Maneb (or zineb or mancozeb) is an ethylenebisdithiocarbamate fungicide. This formulation is poisonous if swallowed, following inhalation of dust or spray mist, or following skin contact. Keep out of the reach of children and pets and keep well away from food or feed stuffs.
It is an irritant to the eyes, nose and throat. Wear protective clothing and wash all clothing thoroughly before re-use. Follow manufacturers' recommended harvest intervals. Clearly label treated seed and grain products, ensure that they are not accessible to domestic animals or wildlife, and cannot be mistaken for food or animal feed. Do not store treated seed or grain for more than one year.
Store all formulations in a dry, well ventilated, cool area, well away from flames or sparks. Ensure adequate air circulation around stored containers. Moisture and heat may cause loss of fungicidal properties and cause formation of flammable vapours.
Maximum residue levels have been recommended by the FAO/WHO Joint Meeting on Pesticide Residues.
Maneb, zineb and mancozeb
PRECAUTIONS IN USE
Maneb, zineb and mancozeb are ethylenebis (dithiocarbamate) fungicides of low acute toxicity. They may be poisonous following ingestion, skin contact or inhalation of spray mists of dusts. Irritation of the nose, eyes, throat or skin may occur and sensitization is possible.
No TLV set. Maximum air concentrations of 0.005 mg/L have been set in the Soviet Union for occupational exposures to maneb and zineb. Closed systems and forced ventilation should be used to reduce exposure to these irritant chemicals.
Clean overalls and impermeable gloves should be worn at all times. When opening a container and when mixing, a face mask and eye protection should also be worn. Mixing, if not mechanical, should always be carried out with a paddle of appropriate length. Applicators should wear clean overalls, impermeable gloves and boots, eye protection and a face mask. Clothing, including the insides of gloves, should be washed with soap and hot water before re-use. Splashes should be washed immediately from the skin or eyes. Hands and exposed skin should be washed before eating, drinking or smoking.
Workers exposed to these fungicides and associated with its application should wear protective clothing (Section 4.1.3).
Workers sensitized to dithiocarbamates should avoid all contact with the formulations, treated plants or contaminated equipment and clothing.
With good agricultural practices, other persons should not be exposed to hazardous amounts of these fungicides. Sensitized individuals may respond to residues at levels that would otherwise be without adverse effect.
Unprotected persons should be kept out of the treated area for at least 24 hours. Sensitized persons should not enter the treated area without protective clothing for four days.
Overalls and impermeable gloves should be worn for all decontamination operations. Eye protection should be worn whilst pouring any formulations. A face mask should be worn when handling dusts and powders. Care must be taken to avoid contamination of all water sources. Keep out of the smoke if residues are burned. Residues in containers should be emptied in a diluted form into a deep pit. The empty container should be buried in this pit or burned. Unused treated seed should be buried in this pit or burned. Unused treated seed should be burned or buried in a deep pit to ensure that it is not available to wildlife or domestic animals.
Spillage of liquid formulations should be contained by absorbent material. This material, or spillage of dry formulations, should be collected and burned or buried. Residual contamination should be removed by washing with detergent and water.
May include itching, scratchy throat, sneezing and cough. Nausea, headache, dizziness and diarrhoea may follow overexposure. Severe poisoning may cause convulsions and coma. Dermal exposure may cause irritation or dermatitis in sensitive individuals. The acute toxicity of dithiocarbamates is increased by alcohol.
The person should stop work immediately, remove contaminated clothing and wash the contaminated skin with soap and water. If the compound has entered the eyes they should be flushed with copious amounts of clean water. If the compound has been ingested, vomiting should be induced only if the patient is fully conscious and if it can be ascertained that the formulation does not contain hydrocarbon solvents. In the event of respiratory failure, artificial respiration should be given.
Maneb, zineb and mancozeb
Maneb, zineb and mancozeb are ethylenebis (dithiocarbamate) fungicides. They may be absorbed from the gastrointestinal tract, from the lungs or from the skin. The acute toxicity is low, but individuals may become sensitized to this class of compound. Ethanol intolerance is not known to occur following exposure to dithiocarbamates.
May include upper respiratory tract or dermal irritation. Nausea, dizziness, headache and diarrhoea may follow ingestion. Severe overexposure may cause convulsions and coma.
Metabolism is probably too rapid for detection of these fungicides in the blood. urinary determination of the metabolite ethylene thiourea may indicate exposure, but is not specific for any one of these fungicides.
Remove contaminated clothing and thoroughly wash contaminated skin. If the compound has entered the eyes, they should be flushed with copious amounts of sterile water or isotonic saline. If the fungicide has been ingested, vomiting should be induced in the conscious patient. Care must be taken to avoid pulmonary complications from hydrocarbon solvents which may be present in the formulation. Activated charcoal should be administered to adsorb the remaining fungicide. A sodium or magnesium cathartic should then be given.
Isolated poisoning incidents attributed to these fungicides have caused convulsions and coma or acute renal failure. Treatment should be symptomatic, ensuring adequate supportive care to prevent long-term complications.
The acute toxicity is low and low level exposure should not elicit serious health problems. In two reported incidents a complete recovery was made despite severe intoxication. If the person becomes sensitized to the fungicides, however, subsequent contact, even at low levels, may elicit a strong dermal reaction. Imbibition of alcohol or exposure to alcohol by any other route should be avoided.
Adams, RM, Manchester RD (1982) Contact Dermatitis, 8(4), 271.
Bauerman LE, Lipworth L & Charkes D (1980). Unpublished Reported submitted to WHO by Rohm and Haas Co., Inc.
Israeli R, Sculsky M, Tiberin P (1983) Scand J Work Environ Health, 9, 47-51.
Kleibl K, Rackova M (1980) Contact Dermatitis 6(5), 348-349.
Koizumi A, Shijojima S, Omiya M, Nakano S, Sato N, Ikeda M (1979). J Amer Med Assoc, 242(23): 2583-2585.
Nater JP, Terpstra H, Bleumink H (1979). Contact Dermatitis, 5(1), 24-26.
Smith D (1976) J Soc Occup Med, 92-94.
Smith D (1984), British J Ind Med, 362-366.
None recommended.
Maneb, zineb and mancozeb may be degraded in the environment and are rapidly metabolized by plants and animals. The majority of the analytical methods determine degradation products and are not specific for any one dithiocarbamate.
Pfugmacher J, Ebing W (1980). Z. Lebensm. unters Forsch, 170(5), 349-354.
Pressley TA, Longbottom JE (1982) The Determination of Dithiocarbamate Pesticides in Industrial and Municipal Wastewaters. Method 630. PB2 156050. EPA-600/4-82-011.
Stevenson A (1972) J Assoc Off Anal Chem 55(5), 939-941.
Tewari SN, Singh R (1979) Fresenius' Z Anal Chem, 294(4), 287.
See Also:
Toxicological Abbreviations
Dithiocarbamates (WHO Pesticide Residues Series 4)
Dithiocarbamates (Pesticide residues in food: 1980 evaluations)
Dithiocarbamates (Pesticide residues in food: 1983 evaluations)