DEMETON         JMPR 1975


         This pesticide was last evaluated by the 1967 FAO/WHO Joint
    Meeting (FAO/WHO, 1968). Data on residues in the total diet and on
    losses during processing and preparation of food required by the 1967
    Meeting have not been supplied. New information an national tolerances
    has become available however, and methods of analysis for disulfoton
    reported to the 1973 Meeting (FAO/WHO, 1974) should be suitable for
    regulatory determinations of demeton.

         Additional or amended national tolerances are summarized in Table
    1 and methods of residue analysis are discussed in the Appraisal

        TABLE 1.  National tolerances for demeton reported to the Meeting
              (Changes and additions since the 1967 Evaluation)


                                                            Tolerance     interval
    Country            Commodity                              mg/kg       (days)

      (provisional)    Apples, barley, grapefruits,           0.4
                       lemons, pears, oranges,
                       table grapes

                       Peaches, plums, damask plums,          0.5
                       sugar beets (roots)

                       Broccoli, cabbage, cauliflower,        0.75
                       celery, cottonseed,
                       Jamaica-peppers, lettuce,
                       pecans, pineapples, potatoes,
                       strawberries, tomatoes,
                       vetches, walnuts

                       Hops                                   1.25

                       Alfalfa (fresh), barley, clover        5.0
                       (fresh), oats, rye (fodder),
                       sugar beets (leaves), wheat

                       Alfalfa (hay), clover (hay)            12.0

                       Broad beans                            0.2

    TABLE 1. (continued)


                                                            Tolerance     interval
    Country            Commodity                              mg/kg       (days)

      ("recommended")  Cereals, fruit, vegetables             0.5
                       (demeton, including demeton-O,
                       demeton-S, demeton-O-methyl,
                       demeton-S-methyl and 

    Canada             Almonds, apples, apricots,             0.75
                       broccoli, Brussels sprouts,
                       cabbage, cauliflower, celery,
                       grapes, lettuce, peaches,
                       pears, peas, pecans, peppers,
                       plums (fresh prunes), walnuts

                       Grapefruit, lemons, oranges,           0.5

                       Beans, muskmelons, tomatoes            0.3

                       Potatoes                               0.2

                       Alfalfa (fresh), barley (grain)        N. R.
                       cottonseed, eggplant, hops,
                       oats (grain), sugar beets,
                       wheat (grain)

    Federal            Cereals                                0.1
    Republic           (disulfoton, 
    of Germany         disulfoton-sulfoxide, 
                       disulfoton-sulfone, demeton-O, 
                       demeton-S, demeton-sulfoxide, 
                       demeton-sulfane: calculated 
                       altogether as disulfoton)

                       Potatoes                               0.2

    Italy              General                                              30

    Netherlands        General                                0

    Norway             General                                              21

    Switzerland        Fruit                                  0.4

    TABLE 1. (continued)


                                                            Tolerance     interval
    Country            Commodity                              mg/kg       (days)

    United States      Alfalfa (hay), clover (hay)            12.0
    of America
                       Alfalfa (fresh), almond (hulls),       5.0
                       barley (green fodder, straw),
                       clover (fresh), oats (green
                       fodder, straw), sugar beets
                       (tops, pulp), wheat (green
                       fodder, straw)

                       Grapes, hops                           1.25

                       Almonds, apples, apricots,             0.75
                       barley (grain), broccoli,
                       Brussels sprouts, cabbage,
                       cauliflower, celery, cotton
                       seed, filberts, grapefruit,
                       lemons, lettuce, muskmelons,
                       nectarines, oats (grain),
                       oranges, peaches, pears,

                       peas, pecans, peppers, plums
                       (fresh prunes), potatoes,
                       strawberries, tomatoes,
                       walnuts, wheat (grain)

                       Sugar beets                            0.5

                       Beans, eggplants                       0.3

                       Sorghum (grain and forage)             0.2

    USSR               Cottonseed-oil                         0.35

    Yugoslavia         General                                0.4         21 proposed

         Data concerning residues in processed food for direct consumption
    and on residues in the total diet which were required by the 1967
    Joint Meeting (FAO/WHO, 1968) have not become available. New
    information on national tolerances has been provided.

         The GLC methods for residue analysis of disulfoton reported by
    the 1973 Joint Meeting (FAO/WHO, 1974) should be suitable for
    regulatory purposes to determine demeton residues present as parent
    compound, demeton sulfoxide or demeton sulphone.

         The Meeting, recognizing the suitability of these procedures, the
    similarity of demeton and disulfoton toxicologically, and the low
    concentration of the residues involved, recommends that residues of
    demeton and/or disulfoton and their several metabolites should be
    expressed as disulfoton for the following reasons.

         (1)  Demeton may also be used in many situations where disulfoton
              is used.

         (2)  Residues of disulfoton also include demeton sulfoxide and

         (3)  It is not always possible or convenient to determine, from
              the residue found, whether demeton has been used as part of
              a programme which also includes disulfoton.

         (4)  Analytical methods suitable for regulatory purposes are most
              conveniently based on the one procedure for both compounds
              and their metabolites.

         Taking these factors into account, and since no new residue data
    have been received, the maximum residue limits listed below are based
    on the data received by the 1967 Meeting taking into account this
    Meeting report and that of 1973 (FAO/WHO, 1974).

         Where demeton and disulfoton have the same or similar use
    patterns, further maximum residue limits are included with those
    recommended for disulfoton (see monograph addendum on disulfoton).


         The following maximum residue limits refer to the total residues
    of demeton, demeton sulfoxide and demeton sulfone determined as
    demeton sulfone and calculated as disulfoton.

    Maximum Residue Limits


         Commodity                             Limit, mg/kg

         Apricots, grapes, peaches             1

         Apples, citrus fruit, pears           0.5

         Plums                                 0.2

         Melons, strawberries                  0.1

         Further maximum residue limits are included in those recommended
    for disulfoton (see this Meeting Report).



         (1)  Validation of residue analytical method for regulatory

         (2)  Residue data from supervised trials for commodities not
              mentioned above or under disulfoton, but included in
              national tolerance lists.

         (3)  Data on residues in commodities moving in commerce.

    See Also:
       Toxicological Abbreviations
       Demeton (FAO Meeting Report PL/1965/10/1)
       Demeton (FAO/PL:1967/M/11/1)