1967 EVALUATIONS OF SOME PESTICIDE RESIDUES IN FOOD
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
This pesticide was evaluated by the 1966 Joint Meeting of the FAO
Working Party and WHO Expert Committee on Pesticide Residues (FAO/WHO,
1967). Since the previous publication, additional information on the
identity of aldrin and the results of additional experimental work
have become available. This new information and work is summarized and
discussed in the following monograph addendum.
Technical aldrin contains : per cent
Other polychloro hexahydro
dimethanonaphthalenes (isodrin) 3.5
(compound 237 or chlordane) 0.5
hexachlorocyclopentadiene (HCCPD) 0.2
hexachloroethane less than 0.1
HHDN diadduct 0.1
bicycloheptadiene (BCH) less than 0.1
other compounds* 3.6
* Primarily a complex mixture of compounds formed by polymerization
of HCCPD and BCH during the aldrin reaction.
EVALUATION FOR TOLERANCES
The annual aldrin and dieldrin production is believed to be in the
order of about 10,000 tons per year, of which aldrin represents the
major portion. Three quarters or more of the total production is used
in agricultural fields, the principal use of both compounds being for
soil treatment. Aldrin residues consist of aldrin and its epoxide
RESIDUES RESULTING FROM SUPERVISED TRIALS
Rootcrop residues will vary depending on a number of factors such as
the crop, the soil residue, the type of soil, the interval between
treatment or planting and harvest and other factors. In normal
agricultural practice where rates of application usually lie between 1
and 3 kg/ha, rootcrop residues will generally lie below 0.15 ppm,
except for radishes, carrots and chicory roots (CCPR, 1967;
Most of the residue found in lettuce is in the outer leaves. After
removing these, the residue in the remainder of the head is below 0.1
ppm, even in the case of the highest residues found. Under conditions
of normal soil usage, residues in other vegetables and in fruit range
generally below 0.1 ppm (CCPR, 1967).
Although radio-tracer studies with very young plants have shown that
dieldrin may be translocated (Morley, 1965), field trials under
practical conditions have demonstrated that no detectable residues
occur in the head in the case of wheat nor in the kernel in the case
of maize, nor in stalks and leaves (CCPR, 1967).
In normal practice rotation of forage crops such as alfalfa, meadow
hay and oats or corn leads to no significant residues in the rotated
crops. (CCPR, 1967). An apparent relationship was noticed between the
oil content of the crop and the amount of dieldrin residue found
therein (Bruce, 1966). For example, rotation of soybeans on corn leads
to residues in the beans ranging below 0.1 ppm (CCPR, 1967). However,
processing of such beans to produce edible oils, fats and meals
removes all residues (Smith, 1967).
Foliage application to fruits (e.g. apples, pears, cherries) under
practical conditions leads generally to low residues in the order of
0.05 ppm and lower. Similar application to other crops leads in
general to low residues, except in the straw of cereals at short
intervals between treatment and harvest, e.g. oats (CCPR, 1967). The
persistence of aldrin on foliage has also been studied by Harrison et
al., 1967. They found a very quick transformation of aldrin to
dieldrin on leaves - 50 per cent of insecticide present was in the
form of dieldrin one week after application. After one week total
residues of aldrin and dieldrin were only about 55 per cent and after
7 weeks 27 per cent of that originally applied.
Seed treatment of vegetables and grain crops - general application
rate 0.1 - 0.15 kg/ha -leads to insignificant residues in the crop
(0.02 ppm or less) (CCPR, 1967).
A study of the milk production and the animal feed and water intakes
at certain U.S.A. dairies which were treated annually with aldrin,
showed insignificant levels of residue in the milk and in the feed and
water intakes. (CCPR, 1967).
RESIDUES IN FOOD MOVING IN COMMERCE
Samples of fruit and vegetables offered for sale in the U.S.A. and
Holland showed residues well within the tolerances, except in the case
of carrots in Holland (CCPR, 1967).
RESIDUES IN FOOD AT TIME OF CONSUMPTION
Total diet studies have been made in the U.S.A., Canada and the U.K.
The most comprehensive, those in the U.S.A., have been conducted over
a period of several years. This work has been summarized by Duggan and
Dawson, 1967. Daily intake of aldrin by food classes was in the range
from 0 to 0.001 mg/day.
FATE OF RESIDUES
Decker et al. (1965) measured the conversion of aldrin to dieldrin in
soil and found that 50 per cent was converted after about 70 days;
however, Edwards and Jeffs (1964) found that about 10 months was
required to convert 50 per cent to dieldrin. On the other hand, Decker
found a half life of aldrin residues (aldrin and dieldrin) below one
month, whereas in the experiments of Edwards and Jeffs this time was
about 19 months. Residue levels of aldrin (mostly present as dieldrin)
do not accumulate indefinitely, as the result of yearly applications
at a constant dosage rate, but will reach a maximum level which is, in
practice, of the order of that resulting from a single annual dose
(Decker, et al, 1965; Elgar, 1966). There is virtually no leaching of
aldrin into deeper soil layers and thus no contamination of ground
water which is eventually used as drinking or irrigation water
(Edwards, 1966; Beynon, Edwards, Thompson, private communication;
Beran and Guth, 1965; Lichtenstein, 1966).
In storage and processing
Most aldrin residues are present as dieldrin although aldrin itself is
better eliminated in processing (Walker, 1965).
Country Tolerance, ppm Crop
Canada 0.1 Asparagus, barley,
celery, corn, cowpeas,
0.25 Beets, beet tops,
squash, Swiss chard,
German Federal The residue on
Republic edible crops
may not exceed
the lower limit
Country Tolerance, ppm Crop
Netherlands * 0.1 fruit and vegetables
in the Residue
decree include the
In the case of
aldrin, dieldrin is
as the main
of this a residue of
aldrin plus dieldrin
together may not
exceed the 0.1
Sweden 0.1 fresh fruits, fresh
Switzerland 0.1 potatoes.
for total residues
of aldrin and its
resulting from the
aldrin in or on raw
Country Tolerance, ppm Crop
0.1 (aldrin Asparagus, broccoli,
grapes, lettuce, mangoes,
pineapple, plums (fresh
zero Alfalfa, apples,
peas, carrots, clover,
collards, corn forage,
corn grain, cowpeas,
cowpea hay, endive
(escarole), garden beets,
garden beet tops,
garlic, grain sorghum,
grain sorghum forage,
mustard greens, onions,
peanut hay, pears, peas,
salsify roots, shallots,
soybeans, soybean hay,
tops, Swiss chard,
turnips, turnip tops.
Country Tolerance, ppm Crop
on an interim
referral to an
0.1 straw of barley, oats,
0.05 grapefruit, lemons,
0.02 grain of barley, oats,
FAO/WHO RECOMMENDATIONS FOR TOLERANCES
The meeting makes no recommendations for tolerances of aldrin per se,
only for aldrin plus dieldrin - see monograph on latter compound.
Further work desirable
Following limited foliar application, aldrin residues as such were
occasionally detected in total diets (Duggan and Weatherwax, 1967).
Therefore further total diet studies are desired.
REFERENCES PERTINENT TO EVALUATION FOR TOLERANCES
Beran, F. and Guth, J.A. (1965) Das Verhalten organischer insektizider
Stoffe in verschiedensen Böden mit besonderer Berücksichtigung der
Möglichkeit einer Grundwasserkontamination. Pflanzenschutzberichte
(Wein), 33 : 65-117.
Bruce, W.N., Decker, G.C., Wilson, J.G. (1966) The relationship of the
levels of insecticide contamination of crop seeds to their fat content
and soil concentrations of aldrin, heptachlor and their epoxides.
J. Econ. Ent. 59 : 179.
CCPR. Aldrin and dieldrin. (1967) Working paper prepared by the
Netherlands Delegation with the assistance of the United Kingdom
Delegation for the Second Session of the Codex Committee on Pesticide
Residues, The Hague. CCPR 67/12.
Decker, G.C., Bruce, W.N., Bigger, J.H. (1965) The accumulation and
dissipation of residues resulting from the use of aldrin in soils.
J. Econ. Ent. 58 : 266 - 271.
Duggan, R.E., Dawson, K. (1967) Pesticides: a report on residues in
food. FDA Papers 1:5
Duggan, R.E., Weatherwax, J.R. (1967) Dietary intake of pesticide
chemicals. Science 157 : 1006-1010.
Edwards, C.A. (1966) Insecticide residues in soils. Res. Rev. 13 :
Edwards, C.A., Jeffs, K.A. (1964) The persistence of some insecticides
in soil and their effects on soil animals. Proc. XII. Int. Congr.
Ent., London, 559-560.
Elgar, K.R. (1966) Analysis of crops and soils for residues of the
soil insecticides aldrin and telodrin. J. Sci. Food Agric. 17 : 541.
FAO/WHO. (1967) Evaluation of some pesticide residues in food. FAO,
PL:CP/15; WHO/Food Add./67.32.
Harrison, R.B., Holmes, D.C., Roburn, J., Tatton, J.O'G. (1967) The
fate of some organochlorine pesticides on leaves. J. Sci. Food Agric.
18 : 10-15.
Lichtenstein, E.P. (1965) Persistence and behaviour of insecticidal
residues in soils and their translocation into crops. Arch. Environs.
Health. 10 : 825-826.
Morley, H.V., Chiba, M. (1965) Dieldrin uptake from soil by wheat
plants. Can. J. Plant Sci. 45 : 209-210.
Smith, et al. (1967) Report on removal of chlorinated pesticides from
crude vegetable oils. Report submitted to U.S. Dept. of Agriculture
and the U.S. Food and Drug Administration in July 1967.
Walker, K.C., Maitlen, J.C., Onsager, J.A., Powell, D.M., Butler,
L.I., Goodban, A.E., McCready, R.M. (1965) The fate of aldrin,
dieldrin and endrin residues during the processing of raw sugar beets.
USDA Bull. ARS 33-107.