DICHLORVOS       JMPR 1974

    Explanation

         The Codex Committee on Pesticide Residues (Alinorm 74/24, para.
    88) requested the Joint Meeting to consider proposals for specific
    tolerances for vegetables, on the basis of residue data to be supplied
    by Governments.

    RESIDUES IN FOOD AND THEIR EVALUATION

         The Monograph from the 1970 Joint Meeting (FAO/WHO, 1971) gives
    data on residues of dichlorvos in vegetables. Further information was
    provided by the Netherlands and Poland, which is summarized in Table
    1.

    APPRAISAL

         The new data support the recommendations made previously for
    "fresh vegetables (except lettuce)" and "tomatoes, mushrooms". It
    appears unnecessary to specify the vegetables in view of the fact that
    this insecticide would be used shortly before harvest to eliminate
    insects that would otherwise be picked with the crop. As the data
    indicate a half-life of not more than 1 day, residues are unlikely to
    reach the consumer.

    RECOMMENDATIONS

         The following tolerance is recommended to replace the existing
    tolerances at the same level for "fresh vegetables (except lettuce)"
    and "tomatoes, mushrooms." Other previously recommended tolerances are
    confirmed.

    TOLERANCE                                     mg/kg

         Vegetables (except lettuce)             0.5

    REFERENCES

    Anonymous. (1974) Specific information to Joint Meeting from the
    Netherlands. (unpublished)

    Anonymous. (1974) Information on dichlorvos residues in vegetables
    from Poland. (Unpublished)

    FAO/WHO. (1971) 1970 Evaluation of some pesticide residues in food.
    AGP/1970/M/12/1.WHO/Food Add./71.42.



    
    TABLE 1  Dichlorvos Residues on Various Crops

                                                                                                                                               

                                               Residue mg/kg/ at interval (days) after application

    Crop            Dosage           0         1           2           3           4           5           6           7           Type of use
                    a.i.
                                                                                                                                               

    Gherkins        500g/ha        0.01-0.02               <0.01                                                                   Glasshouse

    Cucumbers*      33mg/m3        8.1         7.6         0.8         1.0         0.6         0.08        0.1         <0.08       "

    Kohlrabi*       33mg/m3        20.2        12.9        5.6         4.4         1.4         <0.08       <0.08                   "

    Radishes*       0.075%         3.9         0.9         <0.08                                                                   Open air

    Cauliflower*    0.075%         0.9         0.5         0.4                     <0.08                                           "

    Spinach*        0.075%         3.0         0.3                     <0.08       <0.08                                           "

    Lettuce         470g/ha        4.3                                             0.4                                 0.08        Glasshouse

                                   7.4                     1.7                     1.5                                 0.3         "

                    0.1%           42                      1.0         <0.08                                                       "

                    33mg/m3        30.1        16.7        7.3         2.3         0.8         <0.8                                "
                                                                                                                                               

    *  Residues were determined by a biological method using mosquito larvae. The limit of determination was 0.08 mg/kg.
       In other cases residues were determined by cholinesterase inhibition with a limit of determination of 0.01 mg/kg.
    
    

    See Also:
       Toxicological Abbreviations
       Dichlorvos (EHC 79, 1988)
       Dichlorvos (HSG 18, 1988)
       Dichlorvos (ICSC)
       Dichlorvos (FAO Meeting Report PL/1965/10/1)
       Dichlorvos (FAO/PL:CP/15)
       Dichlorvos (FAO/PL:1967/M/11/1)
       Dichlorvos (FAO/PL:1969/M/17/1)
       Dichlorvos (AGP:1970/M/12/1)
       Dichlorvos (Pesticide residues in food: 1977 evaluations)
       Dichlorvos (Pesticide residues in food: 1993 evaluations Part II Toxicology)
       Dichlorvos (IARC Summary & Evaluation, Volume 53, 1991)