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    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)