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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

    DDT

    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 Second Session of the Codex Committee on Pesticide Residues,
    the delegation of Australia proposed that a practical residue limit
    should be established for DDT residues in eggs and suggested a limit
    of 0.5 ppm DDT plus metabolites (CCPR, 1967). The 1967 Joint Meeting
    did not consider the proposal because of the absence of relevant data.
    At the Third Session of the Codex Committee on Pesticide Residues it
    was agreed (CCPR, 1968) that Australia would prepare a submission for
    consideration by the 1968 Joint Meeting (Australia, 1968).

    Residues resulting from supervised trials

    The literature on residues in poultry fat and eggs resulting from the
    controlled use of DDT on and around poultry and from known amounts of
    DDT in poultry feeds is most extensive. Bearsť (1966) has made a
    comprehensive review of the published literature on pesticide residues
    in poultry products.

    The deposition of DDT into chicken eggs from a feed source was
    demonstrated by Rubin et al. (1947). They showed that residues in the
    egg increased as dietary levels of DDT increased.

    The presence of residues in eggs, and poultry tissues resulting from
    the inclusion of alfalfa containing DDT in the ration was reported by
    Draper et al. (1950 and 1952) and Bryson et al. (1950). Liska et al.
    (1964) showed that the feeding of hens on a ration containing 0.1 ppm
    DDT for 30 days resulted in residues in the egg yolk below 0.1 ppm. A
    ration containing 0.5 ppm DDT gave rise to residues of 1.3 ppm DDT in
    egg yolk.

    Bryson et al. (1950) carried out extensive investigations into the
    effect on eggs from feeding DDT-contaminated alfalfa meal in the mash
    of hens. The amount of DDT in the eggs was correlated with the DDT
    intake. Up to 5 ppm DDT in eggs arose from the feeding of a mash
    containing 15 per cent of alfalfa from fields treated with DDT.

    Stadelman et al. (1965) observed that feeding DDT to laying hens by
    capsule at the rate of 0.1 to 0.15 ppm in the diet for 14 days
    resulted in residues in egg yolk. Samples analysed five weeks after
    the feeding period ended contained no residues. Feeding 10-15 ppm of
    DDT for five days resulted in significant residues in eggs which were
    extremely persistent. DDT had disappeared 26 weeks after feeding
    stopped but DDE, the degradation product, persisted beyond that time.

    Of 537 samples of egg pulp examined in Australia during 1966/67, 40
    per cent were found to contain traces of DDT metabolites, most being
    less than 0.25 ppm. Of all the samples examined, only one per cent
    contained residues in excess of 0.5 ppm but nine per cent of samples
    ranged between 0.26 and 0.5 ppm. During 1968 the method of making the
    survey was revised and samples were taken from localities where the
    most significant residues had been found in previous surveys. Of 944
    samples examined, 47 per cent contained detectable quantities of DDT
    and metabolites; 19 per cent contained less than 0.25 ppm, 15 per
    cent between 0.26 ppm and 0.5 ppm and 12 per cent between 0.51 and
    1.0 ppm. Only 1.4 per cent of the subjective samples contained DDT
    and metabolites totalling more than 1.0 ppm. In this survey all
    detectable residues were recorded and added to give the total values
    quoted (Australia, 1968).

    Wesley et al. (1966) carried out an investigation to determine the
    effect of management practices on the depletion of DDT residues in
    eggs of commercial laying hens following a measured exposure to the
    insecticide. Following the administration of DDT the residual DDT in
    the egg yolk declined from a peak of 4.5 ppm to only 0.38 ppm in 17
    weeks.

    Cummings et al. (1966) conducted a low-level feeding experiment with
    laying hens using a mixture of pesticide chemicals. Sixty hens were
    carried for 20 weeks in a study designed to show the residue levels in
    eggs from hens on feed containing 0.05, 0.15 or 0.45 ppm of lindane,
    heptachlor epoxide, dieldrin, endrin, and DDT in combination. The DDT
    was a 70/30 synthetic mixture of p,p'-DDT and o,p'-DDT. The basal diet
    had less than 0.01 ppm of each of the pesticides (and DDE). No report
    was made on the amount of DDD or o,p'DDT that built up. The p,p'-DDT
    and DDE residues at the end of 96 days feeding are shown in Table I.
    The p,p'-DDT appeared to have nearly plateaued at this time but DDE
    continued to increase at a steady rate.

    TABLE I.  RESIDUES IN WHOLE EGGS
                                                    
                          ppm

                                        Total pp'DDT
    Feeding level   p,p'-DDT    DDE       and DDE
                                                    

         0.05       0.06        0.03        0.09
         0.15       0.11        0.04        0.15
         0.45       0.28        0.09        0.37
                                                    

    Ninety-seven per cent of the DDT was in the yolk and three per cent
    in the white.

    Evidence of residues in food moving in commerce or at consumption

    The United States Food and Drug Administration report that 66.4 per
    cent of 2444 samples of domestic shell eggs and 26 per cent of 116
    samples of imported shell eggs, examined in the years 1964 through
    1967, contained DDT or its metabolites. Though the average level of
    these residues was 0.08 ppm and 0.02 ppm respectively, a significant
    proportion of the samples contained residues in excess of 0.1 ppm. By
    far the largest proportion of the residue occurred in the form of DDE.

    Of 537 samples of egg pulp examined in Australia during 1966-67, 40
    per cent were found to contain traces of DDT metabolites, most being
    less than 0.25 ppm. Of all the samples examined, only one per cent
    contained residues in excess of 0.5 ppm but nine per cent of samples
    ranged between 0.26 and 0.5 ppm.

    The data appear to indicate that residues in feed below 0.5 ppm DDT
    would result in eggs with total residues of DDT, DDE and TDE below 0.5
    ppm.

    RECOMMENDATIONS FOR TOLERANCES AND PRACTICAL RESIDUE LIMITS

    Appraisal

    Even in countries such as the United States of America, Canada and
    Australia where the treatment of poultry with DDT is not permitted and
    where DDT is not used for the treatment of cereal grains and animal
    feeds, it has been shown that significant levels of DDT residues occur
    in eggs. The available information indicates that DDT cannot be
    eliminated from the environment or from animal feedstuffs. The
    presence of small quantities of DDT metabolites in egg yolk arises as
    a consequence of the protection of people, food crops and animals from
    insect attack.

    The Codex Committee on Cocoa and Chocolate also requested a tolerance
    for DDT in cocoa and cocoa products, but did not provide sufficient
    data for the meeting to arrive at a decision.

    In respect to the practical residue limits for DDT in whole milk and
    milk products contained in the report and monographs prepared at the
    1967 Joint Meeting (FAO/WHO, 1968a and b), the meeting agreed that
    these recommendations were in error. The practical residue limits for
    milk and milk products (on a fat basis) should have been 0.05 ppm and
    1.25 ppm, respectively.

    Attention should also be drawn to the omission in the 1967 report and
    monographs (FAO/WHO, 1968a and b) of a previously recommended
    temporary tolerance for nuts, on a shell-free basis (FAO/WHO, 1967).

    Recommendations

    In addition to the previously recommended temporary tolerances and
    practical residue limits (as corrected) to be in effect until 1970:

         Temporary tolerances

              Apples, pears, peaches, apricots,
              small fruit (except strawberries),
              vegetables (except root vegetables),
              meat, fish or poultry (on a fat
              basis)                                  7.0 ppm

              Nuts (shelled)                          1.0 ppm

              Strawberries, root vegetables           1.0 ppm

              Cherries, plums, citrus fruit,
              tropical fruit                          3.5 ppm

         Practical residue limits

              Whole milk                              0.05 ppm

              Milk products (on a fat basis)          1.25 ppm

    The meeting also recommends the following practical residue limits
    to be in effect until 1970:

              Eggs (on a shell-free basis)            0.5 ppm

    The above temporary tolerances and practical residue limits are to
    apply to raw agricultural products moving in commerce unless otherwise
    indicated. In the case of fruits and vegetables the tolerances 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 should be applied by the importing
    country at the point of entry or as soon as practicable thereafter.

    REFERENCES

    Australia. (1968) Submission to 1968 Joint Meeting of the FAO Working
    Party of Experts and the WHO Expert Committee on Pesticide Residues.
    Prepared by the Australian Delegation to the Codex Committee on
    Pesticide Residues

    Bearsť, G. E. (1966) Pesticide Residues and Poultry Products: USA
    Legislation and Pertinent Research. Proceedings of the International
    Poultry Conference, 194-2-6 (1966)

    Bryson, M. J., Draper, C. I., Harris, J. R., Biddulph, C., Greenwood,
    D. A., Harris, L. E., Binns, W., Miner, M. L. and Madsen, L. I. (1950)
    DDT in eggs and tissues of chickens fed varying levels of DDT.
    Advances in Chem. Series, 1: 232

    CCPR. (1967) Report of Second Session of the Codex Committee on 
    Pesticide Residues; (ALINORM 68/24)

    CCPR. (1968) Report of Third Session of the Codex Committee on 
    Pesticide Residues; (ALINORM 69/24)

    Cummings, J. G., Zee, K. T., Turner, V., Quinn, F., Cook, R. E. (1966)
    Residues in eggs from low level feeding of five chlorinated
    hydrocarbon insecticides in hens. J. Offic. Anal. Chem., 49: 354-364

    Draper, C. I., Buddulph C., Greenwood, D. A., Harris, J. R.,  Binns,
    W. and Miner, M. L. (1950) Concentration of DDT in tissues in chickens
    fed varying levels of DDT in the diet. Poultry Sci., 29: 756

    Draper, C. I., Harris, J. R., Greenwood, D. A., Biddulph, C.,  Harris,
    I. E., Mangelson, F., Binns, W. and Miner, M. L. (1952) The transfer
    of DDT from the feed to eggs and body tissues of White Leghorn hens.
    Poultry Sci., 31: 388

    FAO/WHO. (1967) Evaluation of some pesticide residues in food.
    (FAO/PL:CP/15; WHO/Food Add./67.32)

    FAO/WHO. (1968a) Report of the 1967 Joint Meeting of the FAO Working
    Party of Experts and the WHO Expert Committee on Pesticide Residues
    (FAO/PL:1967/M/11; Wld Hlth Org. techn. Rep. Ser., 391)

    FAO/WHO. (1968b) 1967 evaluations of some pesticide residues in food
    (FAO/PL:1967/M/11/1; WHO/Food Add./68.30)

    Liska, B. J., Langlois, B. E., Mostert, G. C. and Stadelman, W. J.
    (1964) Residues in eggs and tissues of chickens on rations containing
    low levels of DDT. Poultry Sci., 43: 982

    Rubin, M., Bird, H. R., Green, N. and Carter, R. H. (1947) Toxicity of
    DDT to laying hens. Poultry Sci., 26: 410

    Stadelman, J. W., Liska, B. J., Langlois, B. E., Mostert, G. C. and
    Stemp, A. R. (1965) Persistence of chlorinated hydrocarbon insecticide
    residues in chicken tissues and eggs. Poultry Sci., 44: 435

    Wesley, R. L., Stemp, A. R., Liska, B. J. and Stadelman, W. J. (1966) 
    Depletion of DDT from commercial layers. Poultry Sci., 45 (In press)
    


    See Also:
       Toxicological Abbreviations
       Ddt (ICSC)
       DDT (JECFA Evaluation)
       DDT (PIM 127)
       DDT (FAO Meeting Report PL/1965/10/1)
       DDT (FAO/PL:CP/15)
       DDT (FAO/PL:1967/M/11/1)
       DDT (FAO/PL:1969/M/17/1)
       DDT (Pesticide residues in food: 1979 evaluations)
       DDT (Pesticide residues in food: 1980 evaluations)
       DDT (Pesticide residues in food: 1984 evaluations)
       DDT (JMPR Evaluations 2000 Part II Toxicological)