PESTICIDE RESIDUES IN FOOD - 1984
Sponsored jointly by FAO and WHO
EVALUATIONS 1984
The monographs
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
Rome, 24 September - 3 October 1984
Food and Agriculture Organization of the United Nations
Rome 1985
IMAZALIL
Explanation
Imazalil was reviewed by the Joint Meeting in 1977 and 1980 1/.
At the 1977 JMPR a temporary ADI was allocated and temporary maximum
residue limits were proposed for a small number of commodities such as
bananas, citrus fruit (both post-harvest treatment) and cereal grains
(seed-dressing). The 1980 meeting reaffirmed the TMRLs proposed in
1977 and extended the TADI.
Since these evaluations the use pattern has been expanded in many
countries, especially with respect to post-harvest uses on fruits and
fruiting vegetables. New data were provided to the 1984 JMPR on
residues from supervised trials on a number of these crops, namely
pome fruit, kaki fruit (persimmons), cucumbers, melons and tomatoes;
also on residues from trials on seed potatoes (seed-dressing) and on
pre-harvest foliar applications to strawberries and raspberries.
Information was also obtained on the current status of the
authorisation or registration in several countries and on current
national maximum residue limits.
RESIDUES IN FOOD AND THEIR EVALUATION
USE PATTERN
Imazalil is used as a fungicide against storage rots by post-
harvest application (drench, dip or wax treatment on various fruits
and fruiting vegetables), as a pre-harvest foliar application to some
fruits and vegetables and as a seed-dressing on cereal grains, cotton
seed and seed potatoes.
The main formulations used are EC (emulsifiable concentrate),
200, 500 and 800 g/l, WP (wettable powder) 50 and 75%, an oil ULV
formulation (about 500 g/l) and an LS (solution for seed treatment),
ca. 100 g/l.
The main uses are summarized in Table 1.
1/ See Annex 2 for FAO and WHO documentation.
Table 1. Use pattern of Imazalil
Application
Commodity Disease/Pathogen Rate Type Formulation
1. Post-harvest application
Apples and Storage decay Botrytis cineria 30-50 g/100 l dip LS 100 g/l
pears Monilia fructigena drench WP 75%
Pencillium expsnsum Spray EC 500 g/l
Alternaria tenuis
Bananas Anthracnose Collectorichum musae 30-50 g/100 l dip WP 75%
Crown and Fusarium semitecrum drench
Finger rot F. roseum spray
Neck rot Verticillium theobromae
Ceratocysti C paradoxa
Botriodiploclia theobromae
Citrus Green mould Penicillium digitatum 1 000- in wax, dip EC 800 g/l
fruit Blue mould Penicillium italicurn 2 000 mg/kg drench,
Phomopsis stem Diaporthe citri 25-100 g/100 l spray 95% Tech.
end rot
Diplodia rot Diplodia natalensis WP 75%
Alternaria rot Alternaria citri
Peach Storage decay Monilia fructigena 625 mg/kg in wax EC 500 g/l
Penicillium expansum
Gloeosporium spp.
Pineapple Stem-end rot Thielaviopsis paradoxa 15-20 g/100 l dip WP 75%
Melons Storage rot Fusarium solani 50 g/100 l dip WP 75%
Alternaria spp. 1 000 mg/kg in wax 75% Tech.
Tomatoes Grey rot Botrytis cineria 10-100 g/100 l dip WP 75%
Alternaria rot Alternaria alternata
Table 1. (Continued)
Application
Commodity Disease/Pathogen Rate Type Formulation
II. Foliar Application, Pre-harvest
Bananas Sikatoga Myucosphaerella musicola 100-250 g/ha spray ULV 50%
Black M. fiiiensis var ULV in oil
Sikatoga difformis
Black leaf-streak M. fijiensis
Peach Powdery mildew Sphaerotheca pannosa 30 g/l00 l spray EC 500 g/l
Strawberries Powdery mildew Sphaerotheca macularis 30-40 g/100 l spray EC 200 g/l
S. alchemilla
Leaf spot Alternaria alternata
Gnomonia comari
Diplocarpon earlianum
Cucumbers Powdery mildew Sphaerotheca fuliginae 5-10 g/100 l spray EC 200 g/l
Grey mould Botrytis cineria
Stem and ) Uidmella bryoniae
fruit rot) Mycosphaerella citrulina
Peppers Powdery mildew Oidiopsis tauriea 10-30 g/100 l spray EC 200 g/l
III. Seed Dressing
Cereal seed Leaf Stripe Helminthosnorium sp 5 g/100 l spray various
Fusarium spp.
Septoria spp.
Cotton seed Thielaviopsis basicola 20-30 g/100 spray LS 100 g/l
Fusarium spp. kg seed
Verticillium al bo-atrum
Table 1. (Continued)
Application
Commodity Disease/Pathogen Rate Type Formulation
Seed Potatoes Skin spot Polyseytalum pustulans 10-30 g/1000 kg spray WP 75%
Gungrene Phoma exigua var foveata kg
Silver scurf Helminthosporium solani ULV
Dry rot Fusarium solani
Fusarium sulphureum
RESIDUES RESULTING FROM SUPERVISED TRIALS
Data on residues resulting from post-harvest uses on apples,
pears and some fruiting vegetables (cucumbers, melons, sweet peppers
and tomatoes) were obtained from various countries in Europe and
America (Tables 2-4).
Data on residues resulting from post-harvest uses on seed
potatoes are given in Table 5, and on residues from pre-harvest uses
on raspberries and strawberries from two countries in Table 6.
Post-harvest uses
Apples and pears. The initial residues show some variation,
depending on the mode of application (dip, drench or spray), whether
or not in combination with a wax treatment on the fruit size and skin
texture.
The maximum residue level found if the fungicide is used
according to good (storage) practice is about 5 mg/kg of imazalil
parent compound.
Under good practical storage conditions the initial residue
hardly decreases (at temperatures of about 2-5°C, in the dark or in
poor light). The apparent increase of residue after relatively long
storage periods is mainly due to a loss of weight caused by
evaporation.
Kaki (persimmons). Initial residues resulting from use according to
good practices are of the order of 2 mg/kg. This residue hardly
decreases under normal storage conditions e.g. at low temperatures
(1-5°C).
Fruiting vegetables. In cucumbers, melons, sweet peppers and
tomatoes, the maximum residue levels resulting from uses according to
good storage practices were about 3-4 mg/kg (dip, drench or spray with
imazalil WP or EC in water at dosage rates of 250 to 1,000 mg. a.i/l;
combined wax + imazalil treatment at 2,000 mg/l).
During storage under normal conditions (at temperatures of about
1°C or slightly above, in the dark) the residue decreased only very
slightly, if at all.
Seed potatoes. Since seed potatoes which do not meet the
seed-potato quality standard (especially those too small or too large)
are commonly used as food or feed, the establishment of an MRL may be
desirable.
Table 2. Residues of imazalil in apples from trials carried out in the USA in 1982
Residues, mg/kg
No. of Application Storage
period Imazalil T 8241
trials Rate Formulation
(Replicates) mg a.i./l (weeks) Whole2 Peel Pulp Whole Peel Pulp
or /kg fruit fruit Ref.
1 (5) 1 000 WP 75% 0 1.36 - - 0.02 - - Hamilton,
dip 1 1.76 7.85 1.19 0.09 0.11 0.91 1983a
2 1.10 5.85 0.70 <0.01 0.11 <0.01
4 0.97 4.06 0.66 0.09 0.13 0.09
6 0.72 3.85 0.38 0.03 0.06 0.03
1 (5) 500 WP 75% 0 0.96 - - 0.04 - -
dip 1 0.83 4.37 0.53 0.05 0.11 0.04
2 3.45 3.94 3.41 <0.01 0.10 <0.01
4 0.57 4.83 0.15 0.04 0.15 0.03
6 0.59 2.76 0.39 0.02 0.06 0.01
1 (5) 1 020 EC 680 g/l 0 2.11 - - 0.08 - -
dip 1 4.56 7.67 4.29 0.03 0.09 0.03
2 4.18 11.0 3.54 0.11 0.12 <0.01
4 2.07 11.8 1.02 0.03 0.14 0.02
6 1.57 6.98 1.02 0.04 0.09 0.03
1 (5) 720 Formulation 0 1.51 - - 0.08 - -
1211-3 1 2.33 16.7 1.27 <0.01 0.08 <0.01
2 2.21 8.86 1.43 0.01 0.13 <0.01
4 1.27 7.82 0.74 0.06 1.64 0.05
6 1.39 3.65 1.19 0.04 0.06 0.04
1 (5) 950 Imazalil 0 1.60 - - 0.18 - -
in wax base 1 3.96 9.63 3.47 0.29 1.06 0.22
2 1.94 7.12 1.51 0.09 0.08 0.09
4 1.07 3.24 0.78 0.05 0.11 0.04
6 1.77 6.44 1.38 0.05 0.14 0.04
Table 2 (continued)
Application Residues, mg/kg, average and (range)
No. of Storage
trials Rate Formulation period Imazalil T 8241
(Replicates) mg a.i./l (weeks)
or /kg Whole fruit3 Whole fruit3 Ref.
1 (2) 500 WP 0 1.24 <0.01 Hamilton,
(<0.01 - <0.01) 1983b
1 1.20 0.025
(1.52 - 0.96)
2 1.16 0.06
4 4.41 0.22
8 2.01 0.18
1 (2) 1 000 0 2.48 0.03
(1.48 - 3.47) (<0.01 - 0.05)
1 2.79 0.05
2 3.83 0.02
4 2.57 0.04
8 2.88 0.02
1 (2) 4 000 0 5.54 0.022
(4.98 - 6.09) (0.021 - 0.022)
1 9.25 0.07
2 7.00 0.06
4 9.39 0.14
8 11.5 0.35
1 T 824 = 1-(2,4-dichlorophenyl)-2-imidazol-l-ylethanol
2 Calculated frcm the peel and pulp figures
3 Residues in these trials determined directly on the whole fruit.
Table 3. Residues of imazalil in apples, pears and persimmon, from trials outside the USA, 1979-1984
Application
Commodity Country Year Rate, Formulation No. of trials Storage Residues, Reference
mg a.i/l trials period, mg/kg,
(replicates) months or average and (range)
(days)
Apple Israel 1979 400 1 (3) 0 0.24 (0.20 - 0.28) State Residue
dip 2 0.28 (0.20 - 0.36) Lab.
4 0.37 (0.28 - 0.40)
800 1 (3) 0 0.47 (0.30- 0.60)
dip 2 0.37 (0.20 - 0.42)
4 0.44 (0.38 - 0.50)
Sweden 1982 1,200 1 (1) 7.5 Nordalkali
dip (10) 5.5
(31) 5.2
(93) 8.01
Belgium 1983 500 WP 75% and 1 0 1.80 (1.50 - 2.04) Janssen
EC 500 g/l 5.5 2.04 (1.82 - 2.34)
2
T824 <(1.01
Pear Australia 1983 250 WP and 1 (2) - 0.7 0.35 Anal chem
Var. 375 mixture with 1 (2) 1.2 1.3
Packham 500 DPA and 1 (2) 1.3 1.4
ethoxyquin T 824 <0.02 - 0.04
Var. Beurre 1983 250 WP and 1 (2) 2.0 3.5 Analchum
Bosc 375 mixture with 1 (2) 2.2 3.6
500 DPA and 1 (2) 3.1 3.9
ethoxyquin T 824 <0.02 - 0.4
Table 3. (continued)
Application
Commodity Country Year Rate, Formulation No. of trials Storage Residues, Reference
mg a.i/l trials period, mg/kg,
(replicates) months or average and (range)
(days)
Var. Packham 1983 500 WP and 1 (2) 1.3 1.2 Analchum
mixture with
DPA and
ethoxyquin
Var. Beurre 1983 500 " 1 (2) 4.3 6.1 Analchem
Bosc
Var. Packham 1983 500 WP ? 1 (2) 1.0 1.6 Analchem
T 824 <0.05
Var. Beurre 1983 500 WP ? 1 (2) 3.1 2.2 Analchem
T 824 0.05 - 0.07
Var. Belgium 1983/84 500 WP and 1 (2) 0 2.74 3.15 Janssen
Conference dip EC 500 g/l T 824 <0.01
Persimmon Israel 1979 500 1 (3) 4 ) 0.79 (0.75 - 0.87) AGAN
(kaki) dip 67 ) 0.66 (0.56 - 0.75)
87 ) 0.51 (0.13 - 0.95)
112) 1.2 (0.7 - 1.6)
(stored at -1°C)
4 ) 1.2 (0.9 - 1.5)
67 ) 0.81 (0.72 - 0.95)
87 ) 0.79 (0.52 - 1.12)
112) 1.2 (0.96 - 1.64)
(stored at -1°C)
1 Apparent increase of residue mainly casued by loss of weight due to evaporation
2 See Table 2, footnote 1.
Table 4. Residues of imazalil in fruiting vegetables from trials in various countries 1982-1983
Application
Commodity Country Year Rate, Formulation No. of trials Storage Residues, Reference
mg a.i/l trials period, mg/kg,
(replicates) months or average and (range)
(days)
Fruiting Vegetables
Melons USA 1982/ 1 000 EC 220 g/l 2 - 1.26 (1.24 - 1.28) Pennwalt
(cantaloupes} 83 in wax
2 000 2 - 2.27 (2.14 - 2.40)
in wax
4 000 2 - 4.72 (4.70 - 4.73)
in wax
Israel 1983 1 000 WP 75% 1 (3) 2 AGAN
Peel 3.4 (3.0 - 4.0) Weight
Pulp 0.1 (<0.01 - 0.2) Pulp/peel
=2.7
Cucumber USA 1982 in wax Imazalil 1 (2) 0.62 (0.58 - 0.66) Penwalt
1.5 mg a.i. tech. 98.2%
/kg fruit
3 mg a.i. 1 (2) 1.17 (1.10 - 1.24)
/kg fruit
6 mg a.i.
/kg fruit 1 (2) 2.28 (2.28 - 2.28)
Peppers USA 1982 1 500) Imazalil 1 (2) - 1.49 (1.47 - 1.50) Penwalt
3 000) tech 2.05 (2.00 - 2.10)
6 000) 98.2% 4.25 (4.20 - 4.30)
in wax
Table 4. (continued)
Application
Commodity Country Year Rate, Formulation No. of trials Storage Residues, Reference
mg a.i/l trials period, mg/kg,
(replicates) months or average and (range)
(days)
Israel 1983 1 000 WP 75% 1 (3) 4 2.4 (1.8 - 2.7) AGAN
17 2.3 (2.11 - 2.5)
2 000 WP 75% 1 (3) 4 5.0 (4.0 - 6.0)
1 (3) 17 2.3 (1.8- 2.7)
USA 1982 50 drench 1 (2) 0 0.52 ± 0.07 USDA
3 0.40 ± 0.08
6 0.25 ± 0.05
12 0.05 ± 0.02
100 drench 1 (2) 0 0.55 ± 0.22
3 0.61 ± 0.1
6 0.25 ± 0.02
12 0.11
250 drench 1 (2) 0 1.51 ± 1.23
3 1.35 ± 0.27
6 0.56 ± 0.07
12 0.28
Tomatoes USA 1982 1 500 ) 1 (2) 0 1.22 (1.22 - 1.22) Pennwalt
3 000 ) 1 (2) 1.71 (1.60 - 1.82)
6 000 ) 1 (2) 2.60 (2.40 - 2.80)
in wax
USA 1983 250 ) 1 (2) 2 hours 0.32 Brogdex
500 ) 1 (2) " 0.39
750 ) 1 (2) " 0.44
1 000 ) 1 (2) " 0.42
in wax
Table 4. (continued)
Application
Commodity Country Year Rate, Formulation No. of trials Storage Residues, Reference
mg a.i/l trials period, mg/kg,
(replicates) months or average and (range)
(days)
USA 1983 2 000 ) 1 0 1.67 Brogdex
2 500 ) 1 0 2.54
3 000 ) 1 0 1.89
in wax
1983 2 500 ) 1 0 0.63
3 000 ) 1 0 0.90
3 500 ) 1 0 1.76
in wax
1983 2 500 ) 1 0 0.89
5 000 ) 2.39
7 500 ) 6.12
in wax
Table 5. Residues of imazalil in seed potatoes from trials in Europe, 1978-19Fk4
Application Residues, mg/kg, mean and range)
Variety Country Year No. Rate, Time after Whole Potato Peel Pulp Reference
g a.i/ Formulation treatment,
tonne months
Resy France 1979 1 5.25 EC 1 2.90 ) 11.01 ) 0.07 La Quino
1 10.5 EC 1 9.10 ) 39.06 ) 0.15 Line
(unwashed (unwashed)
Bintje France 1979 1 5.25 EC 1 0.50 ) 1.92 ) 0.08
1 10.25 EC 1 1.90 7.87 0.07
(unwashed) (unwashed)
France 1978 1 20 EC 4 10.28 ) 45.4 ) 0.16 Schering
40 EC 4 30.34 ) 138.8 ) 0.47
60 EC 4 47.50 ) 213.6 ) 0.87
80 EC 4 53.74 ) 229.5 ) 1.07
(unwashed) (unwashed)
Netherlands 1984 1 15 EC 220 g/l 1 3.91 37.4 0.05 Janssen
(3.78-4.07) (36.6-38.3) (0.04-0.05)
1 15 EC 200 g/l 2 4.29 39.6 0.045 Janssen
(4.00-4.47) (35.7-45.1) (0.04-0.05)
UK 1980 1 10 EC 200 g/l 0 4.22 (2.12-5.27) Cayley
35 weeks 1.24 (0.71-2.10)* et al
35 weeks 0.84 (0.47-1.20)**
1980 1 10 EC 200 g/l 0 2.50
1 10 EC 200 g/l 0 5.5
UK 1983 1 15 EC 200 g/l 4.5 0.443 2.76 0.03
(2.38-3.06)
* Sample brushed before analysis.
** Sample washed before analysis.
Table 6. Residues of imazalil in raspberries and strawberries from trials in Europe, 1978-83
(Pre-harvest foliar application)
Application
Commodity Country Year Rate, Formulation No. of PHI, Residues, Reference
g ai/ha or trials days mg/kg,
g ai/100 l average and (range)
Raspberries UK 1978 10 g/100 l EC 1 7 0.94 Hazleton
14 0.09
UK 1980 10 g/100 l EC 1 7 0.32 Hazleton
14 0.22
Strawberries Belgium 1983 400 g/ha EC 200 g/l 1 Before 1.21 Janssen
spraying
after
0 2.0
3 1.4
5 1.0
7 1.2
1 Sampled one week after the last of 12 sprayings
Residues resulting from treatment according to current
recommendations ranged from 2.5 to 5.0 mg/kg depending on the mode of
preparation of the sample before analysis. Residues above 5 mg/kg were
only found when samples were not washed before analysis as recommended
in the FAO Guidelines on residue trials for root and tuber vegetables.
The residue level in washed potatoes or potatoes cleaned by other
adequate methods was not in general above 5 mg/kg.
Foliar, pre-harvest application
Raspberries. Raspberries treated at recommended dosages, about
10 g a.i/100 l, showed residues of 0.04-0.3 mg/kg seven days after
such treatment, and the residue after 14 days was of the same order
(0.09-0.2 mg/kg).
Strawberries. Strawberries treated at recommended dosages (about
400 g a.i./ha) contained residues of 1.2-2.0 mg/kg 0-7 days after the
last application.
Fate of Residues
In plants.
Van Leemput et al. (1984) evaluated the transformation of
14C-imazalil on Golden Delicious apples. Apples were dipped in a
500 mg/l 14C-imazalil solution and subsequently kept in controlled
atmospheric storage for four months.
Another set of apples was treated with unlabelled imazalil. The
apples treated with labelled imazalil were used for the identification
of metabolites and for determining the efficiency of the analytical
extraction procedures. The apples treated with the unlabelled compound
were analyzed by GLC to evaluate the changes in residue levels of the
parent compound and its O-dealkylated transformation product
1-(2,4-dichlorophenyl)-2-imidazol-1-ylethanol (T824 or R 14821)*
during storage. The extraction method removed 93.0 ± 5.6% of the total
imazalil residue. During prolonged storage the residues of imazalil
parent compound hardly declined, remaining in the range of
1.75-2.0mg/kg. The metabolite R 14821 was found only in the samples
taken after 4 months storage. Radio-HPLC revealed only the presence of
the parent compound and the dealkylated metabolite, the latter only in
amounts <3% of the total extractable residue. From the GLC and HPLC
analyses it maybe concluded that under the prevailing storage
conditions (low temperature, absence of light, lowered oxygen partial
pressure), hardly any transformation of imazalil occurs. In addition,
there was some evidence the fungicide was not lost from the treated
fruit by volatilization.
* Identified in the 1977 and 1980 evaluations as -
(2,4-dichlorophenyl)-1H-imidazole-1-ethanol.
Table 7 shows the mass balance, as determined by radio-HPLC
analysis, of 12C-imazalil residues in apples at various intervals
after a post-harvest dip in 500 mg/l imazalil.
Table 7. Composition of imazalil residues in dipped apples
% of total 14C
Interval, months Parent compound R 14821
0 97.6 2.4
1 98.4 1.6
2 97.0 2.9
4 97.9 2.1
METHODS OF RESIDUE ANALYSIS
A GLC method especially designed for the analysis of residues
from post-harvest uses on citrus fruits (Wynants 1977) was described
in the 1977 evaluation. The method has been improved in several
particulars, especially with regard to the efficiency of the
extraction procedures, and it could be adapted for residue analysis on
other commodities including pome fruit and fruiting vegetables such as
cucumbers, melons, tomatoes and peppers.
The method originally designed for the residue analysis of citrus
fruit was not suitable for potatoes because the aqueous solvents
extracted starch which formed intractable emulsions. Specific GLC
methods for the residue analysis of potatoes have been developed
(Wynants, 1979; Cayley et al., 1981). A recently developed method
for potatoes (Janssen, 1983) uses GLC with a nitrogen-phosphorus
thermionic detector and an internal standard:
[1-2-(2,4-dichlorophenyl)heptyll]-1H-imidazole mononitrate. A
recovery of at least 90% was obtained. Woestenborghs et al (1982a,
1982b) developed GLC methods for determining total extractable
residues of imazalil and the O-dealkylated metabolite. The method is
based on the improved extraction of imazalil and its metabolite from
citrus fruits and their products, and conversion of the O-dealkylated
metabolite to its trimethylsilyl derivative. Imazalil and the
derivatized metabolite are determined by GLC with an electron-capture
detector over a linear dynamic range equivalent to 0.005-20mg/kg. No
internal standard is used.
In view of the minor importance of the O-dealkylated metabolite
in the residue arising from post-harvest uses, the methods of choice
which are suitable or can be adapted for regulatory purposes are the
GLC methods described in the first part of this section which
determine only the parent compound.
NATIONAL MAXIMUM RESIDUE LIMITS
The following national MRLs were brought to the notice of the
1984 JMPR. The limits are expressed in mg/kg of the parent compound.
MRL, mg/kg
Country Bananas Citrus
(date MRL established Whole Pulp Whole Pulp Other commodities
Australia - - 5 - Pome fruit 5
Belgium 2 0.2 5 0.1 Strawberries 2
(Feb. 1982) Cucurbits 0.3
Cereals 0.05
Canada - 0.1 5 -
Denmark 2 0.2 5 0.1
Finland 2 0.2 3 0.2
France 2 0.2 5 0.1 Cucurbits 2
Seed Potatoes 2
Fed. Republic of 2 0.2 5 0.1 Cucumbers 2
Germany (1982) Pumpkins 2
Cereals 0.05
Ireland - - 5 -
Israel - - 5 -
The Netherlands 2 5 Fruiting 0.5
(March 1984) vegetables
(including
eggplant,
cucumbers,
gherkins,
melons,
tomatoes)
Cereals 0.05
Meat, milk 0.05
Other food
commodities 0.05
New Zealand - - 5 -
Norway 2 0.2 5 0.1
MRL, mg/kg
Country Bananas Citrus
(date MRL established Whole Pulp Whole Pulp Other commodities
South Africa - - 5 - Cucurbits 0.5
Spain - - 2 -
Sweden 2 0.2 5 0.1
Switzerland 2 0.2 5 0.1
USA 3 0.2 10 - Citrus oil,
citrus pulp
(dried) 25.0
Wheat, barley,
cotton seed 0.05
Wheat and
barley straw 2.0
APPRAISAL
The meeting reviewed information on residue levels of imazalil
from supervised trials of post-harvest uses on apples, pears,
persimmons (kaki-persimmon) cucumbers, melons, tomatoes and peppers.
The fungicide, which is used against storage decay caused by
various fungi, is applied as a dip, drench or spray or mixed in
water-soluble vegetable waxes, The formulations used for the
post-harvest treatments are WP 75%, EC 200 g/l, LS 100 g/l and
technical imazalil (about 95%). Additional information was obtained on
the metabolism of imazalil in plants. The residues on apples during
storage under good storage conditions (low temperature, absence of
light) consisted mainly of the parent compound. The only metabolite
identified on apples after four months storage was O-dealkylated
imazalil in small quantities (<3%).
Information was provided on improvements to the methods of
analysis referred to in the 1977 and 1980 evaluations and on new
methods allowing simultaneous analysis of the parent compound and its
main metabolite, O-dealkylated imazalil. Taking into account that the
residue during storage for four weeks or longer consist almost
entirely of imazalil, the meeting concluded that the present
definition of the residue in terms of the parent compound only should
be retained. Available GLC methods with EC detection which determine
the parent compound only are suitable or can be adapted for regulatory
purposes.
RECOMMENDATIONS
The meeting examined residue data from supervised trials
reflecting current good storage or good agricultural practices and
estimated maximum residue levels which are recommended as temporary
MRLs. The limit for cucumbers replaces the existing level of 0.5 mg/kg
which did not accommodate post-harvest uses. The limits refer to
imazalil only.
Commodity MRL (mg/kg) Pre-harvest interval on
which levels are based (days)
Pome fruit 5 - )
Persimmons (kaki )
persimmon) 2 - )
Cucumbers 5 - )
Melons 5 - ) From post-
Peppers 5 - ) harvest
Tomatoes 2 - ) uses
Potatoes 1 5 - )
Raspberries 2 7 )
Strawberries 2 3-7 )
1 The product is at present authorized for use only on seed
potatoes in three countries. These potatoes are used to some
extent as food or feed.
REFERENCES
1. Residues resulting from supervised trials
All references to supervised trials are unpublished reports
provided to the 1984 JMPR by Janssen Pharmaceutica N.V., Beerse,
Belgium
Adato, I. Imazalil residues in apples. Variety Grand Alexander 1979.
1980 Report of Residue Laboratory, Plant Protection Dept., State
of Israel
Adato, I. Results of residue analysis on bell peppers and melons.
1983 Letter of Dr. I. Adato, Plant Protection Division, Ministry.
of Agriculture, Israel, to AGAN Chemical Manufacturers Ltd.,
Israel. Dec. 1983
AGAN. Imazalil residues in Persimmons. Report of AGAN Chemical
1979/80 Manufacturers Ltd., Israel
Analchem (Australia). Analysis for residues of Imazalil in dipped
1983 pears. Residue analysis Report AC 799/P3. Analchem
Consultants Pty, Ltd. N.S.W., Australia
Brogdex. Imazalil residues on tomatoes, report of Broydex Cy,
1983 California, to Janssen Pharmaceutica, February 1983
Carag, A. Analysis of Imazalil on tomatoes, bell peppers and
1982 cucumbers. Report Project 273-1. Pennwalt Corporation,
U.S.A.
Cayley, R., Hide, G.A. and Tillotson, Y. The determination of Imazalil
1981 on potatoes and its use in controlling potato storage
diseases. Pestic. Sci. 12 103-109
Clark, R.J. Determination of Imazalil residues in cucumbers and
1978 raspberries. Report P527-26/1 1978. Hazleton Laboratories,
Europe
Clark, R.J. Determination of Imazalil residues in cucumbers and
1980 raspberries. Reports 2285-26/3 and 4, 1980. Hazleton
Laboratories, Europe
Dharia, P., and Carag, G. Decay control and residue analysis of
1983 Imazalil on cantaloupes. Report Project 273-17. Penwalt
Corporation, U.S.A.
Hamilton, J.F. Determination of Imazalil and T-824 residues in apples,
1983a Rutgers test. Report Project 82261. Biodynamics, Inc. East
Millstone, New Jersey, U.S.A.
Hamilton, J.F. Determination of Imazalil and T-824 residues in
1983b apples, Michigan test. Report Project 82261. Biojaynamics,
Inc. East Millstone, New Jersey, U.S.A.
Janssen Pharmaceutica. Imazalil/T824 residue levels in apples and
1983-84 pears. Report of Janssen Pharmaceutica, December 1983 and
Addendum January 1984.
King, J.R., Latham, W.G.H. and Spalding, D.H. Gas chromatographic
1982 analysis of Imazalil in peppers. Unpublished report,
Subtropical Horticulture Res. Sta. Florida; U.S. Dept. of
Agriculture, Agriculture Research Service
Nordisk Alhali. Imazalil residues in apples, Cox Orange testing
1982 Alanap, Sweden. Report of Janssen Pharmaceutica
Woestenborghs, R., and van Leemput, L. Residue levels of Imazalil
1984 during storage of potatoes, treated with 15g a.i. per ton,
Internal report, Janssen Pharmaceutica
Wynants, J. Determination of Imazalil in seed potatoes. Internal
1979a report of Janssen Pharmaceutica on La Quinoline trials
Wynants, J. Determination of Imazalil in seed potatoes. Internal
1979b report of Janssen Pharmaceutica on trials by Schering,
France
2. Fate of residues
Van Leemput, L., Ruelens, P., Swysen, E., Hendricks, Michielsen, L.,
1984 Woestenborghs, E., and Heykants, J. On the fate of Imazalil
(R3979) on Golden Delicious apples during a controlled
atmosphere storage for up to four months. Unpublished report
R23979/L6. Janssen Research Products Information Service,
Janssen Pharmaceutica N.V., Beerse, Belgium
3. Methods of residue analysis
Cayley, R., Hide, G.A. and Tillotson, Y. The Determination of Imazalil
1981 on potatoes and its use in controlling potato storage
diseases. Pestic. Sci. 12 103-109
Janssen Pharmaceutica. Determination of Imazalil (R23979) in potatoes.
1983 Unpublished report St-GC 83-37, R23979 potatoes of Janssen
Pharmaceutica N.V., Beerse, Belgium
Woestenborghs, R., Michielsen, L. and Heylants, J. A gas-liquid
1982a chromatographic method for determining total regulable
residues of Imazalil in citrus fruit and citrus by-products.
Unpublished report R 23979/30. Janssen Research Products
Information Service, Janssen Pharmaceutica N.V., Beerse,
Belgium
Woestenborghs, R., Michielsen, L., Meuldermans, W., and Heykants. A
1982b gas-liquid chromatographic method for determining total
regulable residues of Imazalil in citrus fruit and citrus
by-products: validation and application to a residue study
of Imazalil in citrus fruit. Unpublished report R 23979/29.
Janssen Research Products Information Service, Janssen
Pharmaceutica N.V., Beerse, Belgium
Wynants, J. Chromatographic assay methods of Imazalil in citrus fruit.
1977 Proc. Int. Soc. Citriculture 3 1107-1113
Wynants, J. Chromatographic assay methods of Imazalil in potatoes.
1979 Med. Fac. Landbouww., Rijksuniv., Gent. 44 (2) 913-926
See Also:
Toxicological Abbreviations
Imazalil (ICSC)
Imazalil (Pesticide residues in food: 1977 evaluations)
Imazalil (Pesticide residues in food: 1980 evaluations)
Imazalil (Pesticide residues in food: 1984 evaluations)
Imazalil (Pesticide residues in food: 1985 evaluations Part II Toxicology)
Imazalil (Pesticide residues in food: 1986 evaluations Part II Toxicology)
Imazalil (Pesticide residues in food: 1991 evaluations Part II Toxicology)
Imazalil (JMPR Evaluations 2000 Part II Toxicological)
Imazalil (JMPR Evaluations 2001 Part II Toxicological)
Imazalil (JMPR Evaluations 2005 Part II Toxicological)