FAO/PL:1967/M/11/1
WHO/Food Add./68.30
1967 EVALUATIONS OF SOME PESTICIDE RESIDUES IN FOOD
THE MONOGRAPHS
The content of this document is the result of the deliberations of the
Joint Meeting of the FAO Working Party of Experts and the WHO Expert
Committee on Pesticide Residues, which met in Rome, 4 - 11 December,
1967. (FAO/WHO, 1968)
FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS
WORLD HEALTH ORGANIZATION
Rome, 1968
LINDANE
This pesticide was evaluated under the title of "gamma - BHC" by the
1966 Joint Meeting of the FAO Working Party and the WHO Expert
Committee on Pesticide Residues (FAO/WHO, 1967). Since the previous
publication the results of additional experimental work have been
reported. This new work is summarized and discussed in the following
monograph addendum.
IDENTITY
Other relevant chemical properties
Lindane is 99% pure gamma - BHC. Technical BHC contains usually 12
- 13% of the gamma-isomer and is not officially recommended for use on
any crops or food.
In 1963 the USA production of BHC was 3060 tons (including 720 tons of
lindane). World wide use of BHC is estimated by industry (Cela,
private communication) to amount to 60,000-70,000 tons yearly
including 5,000-6,000 tons of lindane.
The 1967 Joint Meeting took note of the statement made by the Codex
Committee on Pesticide Residues regarding the occurence of different
isomers of BHC, particularly the ß-isomer, in human fat and mothers
milk. This matter was discussed and from available evidence it was
clear that the presence of relatively high amounts of ß-isomer can be
explained by the wide use of technical BHC. It was noted that of the
world-wide production only about 10 per cent consists of lindane, the
remaining being technical BHC in which the ß-isomer occurs in
appreciable amounts.
The following discussions are applicable only to the use of lindane.
EVALUATION FOR TOLERANCES
USE PATTERN
Pre-harvest treatments
In Denmark application rates for lindane are established for field
crops at 240 - 400 g/ha, for fruit at 24 - 40 g/ha and for seed
treatment at 0.4 - 0.8 g/kg seed. The minimum interval between use and
harvest is one week (Denmark, 1967).
Generally the application rate is 0.1 - 0.3 kg/ha for foliage
application and 0.75 - 1.5 kg/ha for soil treatment.
RESIDUES RESULTING FROM SUPERVISED TRIALS
On apple trees, the biological half-life time of lindane was
determined by Harrison et al., 1967, to be about three days after
initial deposit of 46 ppm. The following table shows residue data,
found by Majumber, 1967:
Initial application Period after Residues
rate - ppm application ppm Product
12.0 15 months 7.4 stored wheat
8.0 15 months 4.0 stored wheat
4.0 15 months 2.3 stored wheat
0.35 3 days 0.12 snap beans
0.35 4 days n.d. snap beans
0.28 1 day 0.25 tomatoes
0.28 2 days n.d. tomatoes
Sensitivity of analytical method is not known.
Since the application rate on seed (grain, sugar beets) amounts to
only about 75g/ha no residues seem to result.
RESIDUES IN FOOD MOVING IN COMMERCE
In 1966, the following residues of BHC isomers were found in animal
products (Egan, 1967) in the United Kingdom:
Product Source ppm
Milk U.K. 0.0055
Butter Australia 0.05
Denmark 0.05
Irish Republic 0.07
New Zealand 0.01
U.K. 0.07
Beef kidney fat Argentina 0.50
U.K. 0.06
Mutton kidney fat Argentina 0.39
Australia 0.01
New Zealand 0.01
U.K. 0.16
In Great Britain in 1966 fruit and vegetables in commerce were sampled
and lindane residues were generally found in the range from 0. to 0.40
ppm (Dickes, 1967).
RESIDUES IN FOOD AT TIME OF CONSUMPTION
For the period from June to October 1966, lindane residues were found
in 21 of 160 total diet samples in the USA, ranging from traces to
0.09 ppm. The highest residues were found in meat, fish and poultry
(Johnson, 1966).
The daily dietary intake of lindane in 1966 in the USA was 0.00006
mg/kg body-weight and about the same amount of BHC-isomers. The
lindane intake is well below the acceptable daily intake of 0.0125
mg/kg bodyweight (Duggan, 1967). The actual intake of BHC - isomers
shows that these must still be included in considerations. The total
dietary intake of lindane and BHC-isomers was about 8 µg/person/day.
Intake by air was measured in London to be about 0.1 µg/person/day and
by drinking water maximally 0.3 µg/person/day.
FATE OF RESIDUES
General considerations
The solubility of lindane is 10 mg/liter at 20°C = 10 ppm (Maier-Bode,
1965). Wash-off is therefore probably an important factor in
disappearance of residues from leaves as well as in leaching from
soil.
The vapour pressure or lindane is 9.4 × 10-6 mm Hg at 20°C
(Maier-Bode, 1965). Bradbury and Whitaker (1956) found a rapid loss of
lindane from wheat seedlings using 14C labelled insecticide, probably
due to volatilization. Lindane applied to glass plates at 300 - 900
mg/ft sq disappears within 50 - 60 days (Tsao, 1953).
According to Maier-Bode (1965) lindane is stable under the influence
of light and heat as well am in air and water. In sea water the
stability was proved over a period of 12 months (Werner, 1961).
In soils
In India three years after application of 100 lb. and 10 lb. of
lindane/acre 35.9 ppm and 4.45 ppm was found in carrots. In tomatoes
8.00 ppm were found 3 years after soil treatment with 100 lb of
lindane per acre (Majumber, 1967).
In dry soil break-down of lindane to gamma-pentachlorocyclohexene was
2.6 per cent within 64 days, in moist soil 7.1 per cent within 64 days
(Yule, 1967).
In plants
After application of lindane to apple trees, no metabolites could be
detected (Harrison, et al., 1967).
In animals
In the United Kingdom an average value of 0.19 ppm lindane and 0.42
ppm BHC-isomers was found in human fat (Cassidy, 1967). Egan, et al.,
(1965) found 0-1.0 ppm BHC-isomers in human kidney fat and 0.013 ppm
in human milk. In France the average value for BHC residues was 1.19
ppm (Hayes, 1963). In U.S.A. mainly beta BHC and no gamma BHC, was
detected in human fat (Hayes, et al, 1965).
Lindane is quantitatively eliminated by bluegills and goldfish within
two days (Gakstatter, 1967).
NATIONAL TOLERANCES
Country Tolerance Crop
ppm
Benelux 2 (proposed) General
E.E.C. 2 General
Switzerland 1 Fruits,
vegetables
Spain: not allowed on stored products.
RECOMMENDATIONS FOR TOLERANCES AND PRACTICAL RESIDUES LIMITS
Temporary tolerances until 31 December 1970
vegetables and small fruits 3.0 ppm
cereals 0.5 ppm
Practical residue limits
whole milk 0.004 ppm
milk products 0.1 ppm
(on fat basis)
meat 0.7 ppm
(on fat basis)
FURTHER WORK
Further work required before 30 June 1970
Data are needed on the disappearance of residues during storage and
processing of food, and information on the chemical nature of terminal
residues in food as consumed.
Data based on specific methods of analysis identifying residues of
lindane and its metabolites in food moving in commerce.
Further total diet studies concerning the presence of lindane relative
to the other isomers of BHC in food as consumed.
REFERENCES PERTINENT TO EVALUATION FOR TOLERANCES
ASCS (1966) The Pesticide Review.
Bradbury, F.R. and Whitaker, W.O. (1956) The systemic action of
benzene hexachloride in plants: quantitative measurements. J.Sci.Food
Agr., 7:248
Cassidy, W., Fisher A.J., Peden A.J. and Parry-Jones A. (1967)
Organo-chlorine pesticide residues in human fats from Somerset. RAE,
55:546; Mon.Bull.Minist. Hlth., 26;2-6
Denmark, (1967) Statens forsogsvirsomhed i plantekultur.
Specialpraeparater anerkendt af Statens Forsogsvirksomhed i
Plantekultur til bekaempelse af plantesygdomme og skadedyr, p.7, 23,
24.
Dickes, G.J. and Nicholas, P.V. (1967) A survey of fruits and
vegetables for organochlorine insecticides. Ass. of Public Analysts
Journ., June 1967, 52-57.
Duggan, R.E. and Weatherwax, J.R. (1967) Dietary intake of pesticide
chemicals. Science, 157:1006-1010.
Egan, H. (1967) Pesticide quest: Residue surveys and tolerances. Chem.
and Ind., 1721-1730
Egan, H., Goulding, R., Roburn J., Tatton J. O'G. (1965)
Organo-chlorine pesticide residues in human fat and human milk,
Br.Med.J., 2:66-69.
Gakstatter, J.H. and Weiss, C.M. (1967) The elimination of DDT-14C,
Dieldrin-14C, and Lindane-14C from fish following a single sublethal
exposure in aquaria. Trans.Amer.Fish.Soc., 96:301-307.
Hayes, W.J., Dale, W.E. and Burse, V.W. (1965) Chlorinated hydrocarbon
pesticide in the fat of people in New Orleans. Life Sci., 4;
1611 - 1615.
Hayes, W.J., Dale, W.E. and Le Breton, R. (1963) Storage of
insecticides in French people, Nature, 199:1189-1191.
Harrison, R.B., Holmes, D.C., Roburn, J. and Tatton J. O'G. (1967) The
fate of some organo chlorine pesticides on leaves. J.Sci.Food Agr.,
18:10-15.
Johnson, L.Y. (1966) Pesticide residues in total diet samples, Bureau
of Science, Office of Field Scientific Coordination.
Maier-Bode, H. (1965) Pflanzenschutzmittel-Rückstände. Stuttgart,
Ulmer. 455 p.
Majumber, S.K. (1967) A review of the problem of the toxicity of the
pesticidal chemicals in food in India. Ind.Food Packer, 21, (2).
Tsao, C. -H, Sullivan, W.N. and Hornstein, J. (1953) Comparison of
evaporation rates and toxicity to houseflies of lindane and
lindane-chlorinated polyphenyl deposits. J.Econ.Ent., 46;882-884
Werner, A.E. and Waldichuk, M. (1961) Decay of hexachlorocyclohexane
in sea water. J.Fish.Res.Board Canada, 18;287-289; J.Sci.Food Agr.
12:1128 b.
Yule, W.N., Chiba, M. and Morley, H.V. (1967) Fate of insecticide
residues. Decomposition of lindane in soil. J.Agr.Food. Chem.,
15:1000-1004.