Sponsored jointly by FAO and WHO


    The monographs

    Data and recommendations of the joint meeting
    of the FAO Panel of Experts on Pesticide Residues
    in Food and the Environment and the
    WHO Expert Group on Pesticide Residues
    Rome, 24 September - 3 October 1984

    Food and Agriculture Organization of the United Nations
    Rome 1985


    (Demeton-S-methyl, Oxydemeton-methyl and Demeton-S-methyl sulphone)


         Demeton-S-methyl, oxydemeton-methyl (or demeton-S-methyl
    sulfoxide) and demeton-S-methyl sulfone were reviewed at several
    previous meetings (FAO/WHO, 1965b, 1968b, 1969b, 1974b, 1979, 1982 and
    1983). An ADI, based primarily on short-term studies, was established
    in 1965b and was re-affirmed in 1968b. In 1969b, the meeting
    determined that available toxicological studies had not been performed
    on a single defined test compound and that materials used in
    agricultural practice could not be precisely defined. In view of these
    concerns and the lack of long-term toxicological studies, the ADI was
    withdrawn in 1969b and additional information, including longterm
    studies in two species, was required to be submitted. In 1974b, an ADI
    was re-established on the basis of newly submitted long term studies
    on rats and dogs and a teratology study on rabbits. A comprehensive
    and cumulative Monograph on demeton-S-methyl and related compounds was
    presented in the 1974b report. In 1982, the ADI was again withdrawn
    because the rat and dog long-term studies and the rabbit teratology
    study were found to have been conducted in a laboratory where
    unacceptable laboratory standards and practices had been determined to
    exist. Although the dog study was validated by Canadian and US-EPA
    authorities, the rat and rabbit studies were determined to be invalid.

         A series of toxicological studies on demeton-S-methyl,
    oxydemeton-methyl and demeton-S-methyl sulfone were presented to the
    JMPR for consideration in 1983. These studies were not reviewed in
    1983. Since then, additional toxicological studies on oxydemeton-
    methyl have been submitted. All of the studies submitted for
    evaluation in 1983 and 1984 are reviewed in this Monograph Addendum.
    It has been convenient to consider the studies on each compound

    See Also:
       Toxicological Abbreviations