METHOMYL     JMPR 1977

    Explanation

    Methomyl was reviewed by the 1975 and 1976 Joint Meetings (FAO/WHO
    1976,  1977b) and no toxicological data were made available. On the
    other hand, fairly extensive data on use patterns and residues were
    supplied. As a result of this imbalance, the 1976 Joint Meeting was
    unable to determine an acceptable daily intake but it suggested
    guideline levels for residues in several crops. Full toxicological
    data were required and an improved residue analysis procedure,
    information on the fate of the compound during storage or in
    processing and information on national use patterns and residue data
    from countries other than Australia, Netherlands, and USA were listed
    as desirable.

    None of the requirements have been met, except that additional data
    were submitted by the Netherlands on the use pattern in tomatoes and
    bell peppers and residues in tomatoes.

    RESIDUES IN FOOD AND THEIR EVALUATION

    USE PATTERN

    In the Netherlands, methomyl is used in tomatoes and bell peppers at
    the dosage rate of 25 g/100 1. at 1700 1/ha, with a recommended
    pre-harvest interval of 3 days. Both 25% and 20% EC formulations are
    used.

    RESIDUES RESULTING FROM SUPERVISED TRIALS

    The residues obtained in the Netherlands on tomatoes were generally
    low, 0.01-0.06 mg/kg at the pre-harvest interval of 0-3 days and
    application rates of 0.75-1.25 kg a.i./ha.

    METHODS OF RESIDUE ANALYSIS

    Although the method of Pease and Kirkland (1968) suffers from emulsion
    and interference problems, it may be used for regulatory purposes on a
    case-to-case basis. Some refinements or modifications are still
    required for it to be accepted as a regulatory method. In the
    Netherlands, a modification of the procedure was used and no
    difficulties were encountered. The limit of determination was 0.01
    mg/kg.

    APPRAISAL

    The only submission received by the 1977 Joint Meeting was that from
    the Netherlands which dealt with use patterns in tomatoes and bell
    peppers and residue data on tomatoes. Residues of methomyl were
    generally low, 0.01-0.06 mg/kg, at the pre-harvest interval of 0-3
    days. The residue method used was a modification of that of Pease and

    Kirkland (1968) and no difficulties were encountered. The limit of
    determination was 0.01 mg/kg.

    FURTHER WORK OR INFORMATION

    As listed in the Report of the 1976 Joint Meeting (FAO/WHO 1977a, P.
    33).

    REFERENCES

    Pease, H.L. and Kirkland, J.J. (1968) Determination of methomyl
    residues using micro colorimetric gas chromatography. J. Agr. Food
    Chem., 16: 554-557.

    FAO/WHO (1976) 1975 evaluations of some pesticide residues in food.
    AGP:1975/M/13; WHO Pesticide Residues Series No. 5.

    FAO/WHO (1977a) Pesticide residues in food. Plant Production and
    Protection Series No. 8, WHO Technical Report Series No. 612.

    FAO/WHO 1976 evaluations of some pesticide residues in food.
    AGP:1976/M/14.
    

    See Also:
       Toxicological Abbreviations
       Methomyl (EHC 178, 1996)
       Methomyl (HSG 97, 1995)
       Methomyl (ICSC)
       Methomyl (WHO Pesticide Residues Series 5)
       Methomyl (Pesticide residues in food: 1976 evaluations)
       Methomyl (Pesticide residues in food: 1978 evaluations)
       Methomyl (Pesticide residues in food: 1986 evaluations Part II Toxicology)
       Methomyl (Pesticide residues in food: 1989 evaluations Part II Toxicology)
       Methomyl (JMPR Evaluations 2001 Part II Toxicological)