Sponsored jointly by FAO and WHO


    Joint meeting of the
    FAO Panel of Experts on Pesticide Residues
    in Food and the Environment
    and the
    WHO Expert Group on Pesticide Residues
    Geneva, 3-12 December 1979



    This compound was previously evaluated in 1975, in 1977 and in 1978.
    The 1979 CCPR requested the meeting to review three separate matters
    relating to previously recommended MRLs.

    1.  That the MRLs for edible offal, meat, milk and milkproducts be
    converted to ERLs.

    2.  That different MRLs be proposed for liver and kidney instead of
    the single level of 2 mg/kg recommended for kidney and liver of
    cattle, goats, pigs and sheep.

    3.  That the recommended levels on milk and milk products be
    re-evaluated to reconcile the differences between the US and the CCPR
    limits bearing in mind that both are based on the same US data.

    Review (in respective order)

    1.  The current interpretation of the definitions of MRL and ERL
    (Report Meeting 1975) justify the continued use of MRL limits of
    sec-butylamine since the residues of sec-butylamine in feedstuffs are
    controllable by agricultural practices.

    2.  The data on liver and kidney are contained in reports of
    twostudies (Eli Lilley 1967) and (Peoples, 1968).  The test animals in
    the first experiment were dairy cattle fed graduated levels of 100,
    20, 5 and 2 ppm.  In the second experiment cows were fed citrus pulp
    from treated oranges at a rate equivalent to 16 ppm in the total diet.
    There are adequate data to show that different MRL levels would be
    appropriate for liver and kidney as suggested by CCPR.  However, the
    specific levels require a re-evaluation of the results of the two
    studies in relation to a dietary intake adjusted for the proportion of
    dried citrus pulp and molasses in the animal diets.

    Based on data in the 1975 Meeting, maximum residues in oranges and
    grapefruit would approximate 20 mg/kg.  Data indicate a 3-fold
    concentration in processing the fresh fruit to dried citrus pulp and
    molasses, which would yield a maximum of 60 ppm in pulp and molasses.
    Since the pulp and molasses normally comprise about 30% of the total
    cattle diet, this would be equivalent to 18 ppm in the total diet.
    This approximates the level of 16 ppm fed in the Peoples (1968)
    experiment which showed a range of 0.56 to 2.7 mg/kg in kidney and
    0.15 to 0.20 mg/kg in liver.  The other study (Eli Lilley, 1967)
    requires interpolation between the 10 ppm and 100 ppm feeding levels
    which yields approximately 0.32 in kidney and 0.15 in liver.  Despite
    the somewhat different results in the two studies, it was concluded
    that an MRL of 3 mg/kg would be appropriate for kidney and 0.2 ppm for

    3.  Based on the two experiments discussed above, and using the same
    adjusted dietary intake from citrus pulp and molasses, the data show
    that an MRL of 1.0 mg/kg would be required to cover sec-butylamine
    residues occurring in milk, including endogenous sec-butylamine.  The
    most pertinent study, from the stand point of approximating the
    anticipated dietary exposure, was Peoples, 1968.  In that experiment,
    5 analyses (maximum 0.67 mg/kg) exceeded the present CCPR MRL of 0.5
    mg/kg and nine other figures approximated 0.5 mg/kg.

    It is sometimes a practice to recommend MRLs for milk based on average
    residue values because of the mixing that occurs in commercial dairy
    operations.  The mean value from all milk samples was 0.5 mg/kg.
    However, because endogenous sec-butyalmine in milk will vary and
    cannot be distinguished from the sec-butylamine added through the
    pesticidal use, the meeting concluded that a MRL of 1 mg/kg would be

    Sec-Butyalmine is not lipophilic and would not be expected to 
    concentrate in high fat dairy products.  No residue analyses were
    available on milk products.  The previous (1977) recommendation for a
    MRL on milk and milk products was based on terminology in use at that
    time.  It was concluded that the MRL for milk products was unnecessary
    and should be deleted.


    1.  That the present MRLs not be converted to ERLs

    2.  That the present MRL of 2 mg/kg for kidney and liver be deleted
    and replaced by an MRL of 3 mg/kg for kidney and 0.2 mg/kg for liver

    3.  That the present MRL for milk be increased to 1.0 mg/kg and

    4.  That the MRL for milk products be deleted.


    Eli Lilly.  Submission to 1975 JMPR, VPR-107-741 (1967).

    Peoples.  Report from School of Veterinary Medicine, Univ. Calif.
    Davis, 1968.

    See Also:
       Toxicological Abbreviations
       Butylamine, sec- (WHO Pesticide Residues Series 5)
       Butylamine, sec- (Pesticide residues in food: 1977 evaluations)
       Butylamine, sec- (Pesticide residues in food: 1978 evaluations)
       Butylamine, sec- (Pesticide residues in food: 1980 evaluations)
       Butylamine, sec- (Pesticide residues in food: 1981 evaluations)