FAO/PL:1969/M/17/1

    WHO/FOOD ADD./70.38

    1969 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
    Group on Pesticide Residues, which met in Rome, 8 - 15 December 1969.

    FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

    WORLD HEALTH ORGANIZATION

    Rome, 1970


    PYRETHRINS AND PIPERONYL BUTOXIDE

    Explanation

    These pesticides were evaluated by the 1966, 1967 and 1968 Joint
    Meetings (FAO/WHO, 1967b, 1968b, 1969b).* At the Fourth Session (1969)
    of the Codex Committee on Pesticide Residues the delegation of Canada
    pointed out the need for tolerances for residues of pyrethrins and
    piperonyl butoxide on dried codfish. Supporting data were submitted
    and evaluated at this 1969 Joint Meeting.

    RESIDUES IN FOOD AND THEIR EVALUATION

    CODFISH

    The use of pyrethrins piperonyl botoxide emulsions to protect light
    salted codfish from blow fly attack during the drying process is
    practised in Newfoundland and possibly elsewhere. The technology for
    protection against the species Lucillia illustris (Meig) and
    Calliphora terranovae (Macq.) has been described (Morris and
    Andrews, 1968). Fish taken from brine barrels are washed in salt water
    and dipped in insecticide emulsion for 3-5 seconds. They are
    immediately spread on trays to dry in the sun and wind. Recently it
    has been found possible to reduce the concentration of insecticide in
    the emulsion to 0.0625 percent pyrethrins and 0.125 percent piperonyl
    butoxide (technical) and still maintain protection.

    Residues resulting from supervised trials on codfish

    Fifty fish were dipped in the emulsion (0.0625 percent pyrethrins,
    0.125 percent piperonyl butoxide) and fifty fish were left untreated
    as checks on 14 September 1968. Following drying in regular commercial
    manner, treated and untreated fish were sampled on 23 October and
    shipped by air for analysis. The analyses were carried out by a method
    reported by McGlaughlin Gormley King Co. based on the use of a gas
    chromatographic method and detector cell described by Bruce (Bruce,
    1967). Replicated analyses showed levels of 0.051 to 0.066 ppm
    pyrethrins and 0.76 to 0.97 ppm piperonyl butoxide (0.87 to 1.1 ppm
    technical) in the fish. This is representative of residues in the
    product as moving in commerce. Such fish would be soaked or boiled in
    water before consumption.

    Methods of residue analysis

    The methods of analysis outlined above should be evaluated for use as
    regulatory methods. They have been reported to the IUPAC Commission on
    Development, Improvement and Standardization of Methods of Pesticide
    Residue Analysis.

    FRESH FRUIT AND VEGETABLES

    The new data that had been mentioned at the Fourth Session of the
    Codex Committee on Pesticide Residues were not available for
    consideration at the meeting. Whilst examining the data available it
    was noted that the monograph for the 1968 meeting (FAO/WHO, 1969b)
    contained the reservation "for canning only" against the
    recommendation for a tolerance for piperonyl butoxide but not for
    pyrethrins.

    Recommendation

    After discussion it was decided that the limiting words should be
    deleted from the recommendations pertaining to piperonyl butoxide.

    RECOMMENDATIONS FOR TEMPORARY TOLERANCES

    The following temporary tolerances, to be in effect until 1972:

    a) Dried codfish moving in commerce:

    pyrethrins          -  0.1 ppm
    piperonyl butoxide  -  1.0 ppm

    b) Fresh fruit and vegetables (amendment)

    The words "for canning only" should be deleted from the
    recommendations included in the records of previous meetings,

    FURTHER WORK REQUIRED (by 30 June 1972)

    In addition to "Further Work" included in FAO/WHO 1967b) and 1968b,
    experience and residue data from similar trials with dried fish in
    other countries.

    REFERENCES

    Bruce,  W.N. (1967) Detection cell for measuring picogram quantities 
    of organophosphorus insecticides, pyrethrins synergists and other
    compounds by gas chromatography. J.Agr.Fd.Chem. 15: 178-81

    Morris, R.F. and Andrews, D. (1968) Investigations into the use of 
    pyrethrins and other insecticides for the control of blowfly. 
    Calliphura terranovae (Macq.) infesting light salted codfish in
    Newfoundland. Purethrum Post 9: 9-13

                 
    * See Appendix II
    

    See Also:
       Toxicological Abbreviations
       Piperonyl butoxide (ICSC)
       Piperonyl Butoxide (FAO Meeting Report PL/1965/10/1)
       Piperonyl butoxide (FAO/PL:CP/15)
       Piperonyl butoxide (FAO/PL:1967/M/11/1)
       Piperonyl butoxide (WHO Pesticide Residues Series 2)
       Piperonyl butoxide (Pesticide residues in food: 1992 evaluations Part II Toxicology)
       Piperonyl butoxide (Pesticide residues in food: 1995 evaluations Part II Toxicological & Environmental)
       Piperonyl Butoxide (IARC Summary & Evaluation, Volume 30, 1983)