FAO/PL:1968/M/9/1
WHO/FOOD ADD./69.35
1968 EVALUATIONS OF SOME PESTICIDE RESIDUES IN FOOD
THE MONOGRAPHS
Issued jointly by FAO and WHO
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 Geneva, 9-16 December,
1968.
FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS
WORLD HEALTH ORGANIZATION
Geneva, 1969
HEPTACHLOR
Since the previous evaluation (FAO/WHO, 1968), additional data have
become available and are summarized and discussed in the following
monograph addendum.
RESIDUES IN FOOD AND THEIR EVALUATION
Background
At the Third Session of the Codex Committee on Pesticide Residues the
delegations of Germany and the Netherlands requested the Joint Meeting
to consider the advisability of establishing a practical residue limit
in sugar beets while the delegation of the Netherlands requested the
Joint Meeting to consider the advisability of establishing a practical
residue limit in carrots and to exclude this commodity from the
current tolerance figure, thus precluding the use of heptachlor for
carrot insect control but accommodating heptachlor residues in carrots
resulting from the prior use of the compound in the protection of
other crops.
Use pattern
Pre-harvest treatments
Heptachlor is recommended in some countries for seed treatment of
sugar beets, the resulting residue being quite small in sugar beet
pulp, an important animal feed. However, excessive pesticide residues
in the pulp can result in undesirable residues in animal products.
There is no reason to believe that heptachlor residues will appear in
sugar consumed by man.
Sugar beets are grown in rotation with other crops, heptachlor
sometimes having been used for the control of associated soil insects
such as wireworms and root maggots.
Residues resulting from supervised trials
Residue data developed in Canada prior to 1964 using older analytical
methods are extremely variable as shown below (Allen et al., 1962):
Formulation Heptachlor epoxide residue (ppm)
Manitoba Alberta
(rainfall heavy soil) (irrigated light soil)
Applications to seed furrow
Fertilizer 0.16 0.0
0.21 0.0
(continued)
Formulation Heptachlor epoxide residue (ppm)
Manitoba Alberta
(rainfall heavy soil) (irrigated light soil)
Applications to seed furrow
Attapulgite 0.07 0.12
0.48 0.15
Vermiculite 0.09 0.0
0.0 0.0
Applications to soil surface
Attapulgite 0.0 0.44
0.0 0.23
Vermiculite 0.0 0.39
0.0 0.15
Untreated Nil Nil
Carrots are well known for their unusual ability to absorb residues of
cyclodiene insecticides from soil (Glasser et al., 1958; Lichtenstein,
1960; Lichtenstein et al., 1964; Schupan, 1960; Fox et al., 1964).
However, all available data include treatments in the year of
planting. Varietal trials (Lichtenstein at al., 1965) indicate that
there is considerable variation in the amount of residue from this
source also due to soil type. Carrots grown in soil treated with
chlordane may also contain small quantities of heptachlor. Most of
these investigations suggest that some carrots from a field will
contain more than 0.1 ppm if heptachlor has been used in dosages of
over one pound per acre in the year of planting. However, only 0.03
ppm was found when 0.31 and 0.63 kg/ha were used (Dawsey et al.,
1961).
A soil monitoring study in the United States of America (Seal et al.,
1967) reports the results of a survey of 49 fields sampled in the
eastern United States of America in 1965. Heptachlor and/or heptachlor
epoxide was found in soil of five of 19 carrot fields' samples (0.06
to 0.26 ppm). However, only two carrot samples contained residues
(0.06 to 0.08 ppm).
Data based on reliable analytical methods are not available to relate
residues in sugar beets and carrots to prior applications of
heptachlor. However, data may be available in 1969 from experiments
underway in 1968.
Evidence of residues in food in commerce or at consumption
In the United States of America (which has the highest scale of use of
heptachlor), the monitoring of raw root crops (except potatoes) in
1964, 1965 and 1966 showed average residues of 0.001 ppm, and total
diet studies (food as consumed) indicate an average daily intake of
0.00003 mg/kg body weight (for all food).
RECOMMENDATIONS FOR TOLERANCES AND PRACTICAL RESIDUE LIMITS
Appraisal
In respect to sugar beets, the only available residue data leave much
to be desired concerning the reliability of analytical methods and
variations in results. They suggest that method and rate of
application, carrier for insecticide, soil type and climatic factors
will affect the amount of residues picked up by sugar beets from soil.
Data were not available on the results of supervised trials carried
out with reliable analytical methods which would relate currently
employed dosages of heptachlor and heptachlor epoxide in soil
resulting from a previous year(s) treatment of residues in sugar beets
subsequently grown in that soil but not treated in the year of
planting.
Because of the unusual ability of carrots to absorb cyclodiene
pesticide residues from soil and the absence of data relating prior
treatments of heptachlor and residues in soil to residues in carrots
grown in subsequent years, carrots should be excluded from the
previously recommended temporary tolerance for root vegetables and a
temporary practical residue limit should be established.
Recommendations
Temporary tolerances
The previously recommended temporary tolerances, to be in effect until
1970, are amended to exclude carrots and therefore are now as follows
(to apply to heptachlor and heptachlor epoxide):
Root vegetables (other than potatoes and
carrots), cole crops, other leafy vegetables - 0.1 ppm
Practical residue limits
The previously recommended practical residue limits, to be in effect
until 1970, are amended to include carrots and therefore are now as
follows (to apply to heptachlor and heptachlor epoxide):
Whole milk 0.005
Milk products (on fat basis) 0.125
Meat (on fat basis) 0.2
Raw cereals 0.02
Vegetables, except carrots 0.05
Carrots 0.1
In the case of fruit and vegetables the tolerances and practical
residue limits should be applied as soon as practicable after harvest
and in any event prior to actual retail to the public. In the case of
commodities entering international trade, the tolerances and practical
residue limits should be applied by the importing country at the point
of entry or as soon as practicable thereafter.
Further work or information
Required before 30 June 1970:
1. Data from supervised trials on (a) the content of residues in soils
treated for one, two and three or more years with heptachlor and
(b) the content of residues in carrots grown in the treated soils
at various intervals after cessation of treatment.
2. Data on unintentional residues in sugar beets and sugar beet pulp
to indicate the maximum residue of heptachlor and heptachlor
epoxide that may be fed to meat- and milk-producing animals without
exceeding the currently recommended practical residue limits for
these animal products.
3. Data on residues in sugar beets and sugar beet pulp from furrow
seed treatment and coated seed treatment.
REFERENCES
Allen, W. R., Harper, A. M. and Lilly, C. E. (1962) Effect of
heptachlor formulation and placement on the control of sugar beet root
maggot and residues in sugar beets. Pesticide Research Report, (Can.)
National Committee on Pesticide Use in Agriculture 1962, pp. 57-58
Dawsey, L. H., Woodham, D. W. and Lofgren, C. S. (1961) Heptachlor and
heptachlor epoxide residues in truck crops. J. Econ. Entomol., 54:
1264-1265
FAO/WHO. (1968) 1967 evaluations of some pesticide residues in food
(FAO, PL:1967/M/11/1; WHO/Food Add./68.30)
Fox, C. J. S., Chisholm, D. and Stewart, D. K. R. (1964) Effect of
consecutive treatments of aldrin and heptachlor residues in rutabagas
and carrots and on certain soil arthropods and yield. Can. J. Plant
Sci., 44: 149-156
Glasser, R. F., Blenck, R. C., Dewey, J. E., Hilton, B. D. and
Weiden, M. H. J. (1958) Occurrence of a toxic non-aldrin residue in
carrots grown on aldrin-treated soil. J. Econ. Entomol., 51: 337-341
Lichtenstein, E. P. (1960) Insecticidal residues in various crops
grown in soil treated with abnormal rates of aldrin and heptachlor.
J. Agr. Food Chem., 8: 448-451
Lichtenstein, E. P., Myrdal, G. R. and Schulz, K. R. (1964) Effect of
formulation and mode of application of aldrin in the loss of aldrin
and its epoxide from soils and their translocation into carrots.
J. Econ. Entomol., 57: 133-136
Lichtenstein, E. P., Myrdal, G. R. and Schulz, K. R. (1965) Absorption
of insecticidal residues from contaminated soils into five carrot
varieties. J. Agr. Food Chem., 13: 126-131
Schupan, W. (1960) Residues of aldrin and dieldrin in the roots of
carrot and their effect on the biological value. Z. Pflanzenkrankh.
u Pflanzenschutz, 22: 340-351
Seal, W. L., Dawsey, L. H. and Cavin, G. E. (1967) Pesticides in soil:
Monitoring for chlorinated hydrocarbon pesticides in soil and root
crops in Eastern States in 1964. Pesticide Monitoring Jour., 1:
22-25
See Also:
Toxicological Abbreviations
Heptachlor (EHC 38, 1984)
Heptachlor (HSG 14, 1988)
Heptachlor (ICSC)
Heptachlor (PIM 578)
Heptachlor (FAO Meeting Report PL/1965/10/1)
Heptachlor (FAO/PL:CP/15)
Heptachlor (FAO/PL:1967/M/11/1)
Heptachlor (FAO/PL:1969/M/17/1)
Heptachlor (AGP:1970/M/12/1)
Heptachlor (WHO Pesticide Residues Series 4)
Heptachlor (WHO Pesticide Residues Series 5)
Heptachlor (Pesticide residues in food: 1991 evaluations Part II Toxicology)
Heptachlor (CICADS 70, 2006)