FAO Nutrition Meetings
    Resort Series No. 44A
    WHO/Food Add./68.33




    TOXICOLOGICAL EVALUATION OF SOME
    FLAVOURING SUBSTANCES AND
    NON-NUTRITIVE SWEETENING AGENTS





    Geneva, 21-28 August 1967



    The Eleventh Report of the Joint FAO/WHO Expert Committee on Food
    Additives is published as FAO Nutrition Meetings Report Series,
    1967, No. 44; Wld Hlth Org. techn. Rep. Ser., 1968, 383. This
    Report contains general considerations, including the principles
    adopted for the evaluation, and a summary of the results of the
    evaluations of a number of food additives. Additional information,
    such as biological data and a toxicological evaluation, considered at
    that meeting, is to be found in this document.


    Food and Agriculture Organization of the United Nations
    World Health Organization
    1967


    ISOAMYL BUTYRATE

    Chemical name            Isoamyl butyrate

    Empirical formula        C9H18O2

    Structural formula       CH3(CH2)2COOC5H11

    Molecular weight         158.24

    Definition               Isoamyl butyrate contains not less than 98
                             per cent. and not more than the equivalent
                             of 101 per cent. C9H18O2.

    Description              A colourless liquid having a strong,
                             characteristic fruity odour. It is usually
                             prepared by esterification of isoamyl
                             alcohols with butyric acid.

    Biological Data

    Biochemical aspects

         There are no experimental data on this compound available.

    Acute toxicity

                                                                       

    Animal          Route      LD50              References
                               (mg/kg 
                               body-weight)
                                                                       

    Rat             oral       12 210            Jenner et al., 1964

    Guinea-pig      oral       11 950            Jenner et al., 1964
                                                                       

    Short-term studies

         Rat. Groups of 10 male and 10 females were fed diets containing
    0, 0.1, 0.25 and 1.0 per cent. ester for 16 weeks. No adverse effects
    were noted on body-weight gain, food intake and general condition.
    Haematological investigation and histological examination of all major
    tissues revealed no abnormality, and the weights of the major organs
    were comparable with those of the control group (Hagan et al., 1967).

    Long-term studies

         None available.

    Comments

         This ester is probably hydrolyzed to amyl alcohol and butyric
    acid. The short-term animal studies permit evaluation. Metabolic
    studies are essential

    EVALUATION

    Level causing no toxicological effect

         Rat. 1 per cent. (= 10 000 ppm) in the diet, equivalent to 500
    mg/kg body-weight/day.

    Estimate of acceptable daily intake for man

                                        mg/kg body-weight

         Conditional acceptance               0-5

    Further work required

         Biochenical and metabolic studies in animals and man.

    REFERENCES

    Hagan, E. C., Hansen, W. H, Fitzhugh, O. G, Jenner, P. M., Jones, W.
    I., Taylor, J. M., Long, E. L., Nelson,  A. A. & Brouwer, J. B. (1967)
    Fd Cosmet. Toxicol., 5(2), 141

    Jenner, P. M., Hagan, E. C., Taylor, J. M., Cook, E. L. & Fitzhugh, O.
    G. (1964) Fd Cosmet. Toxicol., 2, 327
    

    See Also:
       Toxicological Abbreviations
       ISOAMYL BUTYRATE (JECFA Evaluation)