FAO Nutrition Meetings
    Report Series No. 40A,B,C
    WHO/Food Add./67.29




    TOXICOLOGICAL EVALUATION OF SOME
    ANTIMICROBIALS, ANTIOXIDANTS, EMULSIFIERS,
    STABILIZERS, FLOUR-TREATMENT AGENTS, ACIDS AND BASES





    The content of this document is the result of the deliberations of the
    Joint FAO/WHO Expert Committee on Food Additives which met at Rome,
    13-20 December, 19651 Geneva, 11-18 October, 19662




                   

    1 Ninth Report of the Joint FAO/WHO Expert Committee on Food
    Additives, FAO Nutrition Meetings Report Series, 1966 No. 40; 
    Wld Hlth Org. techn. Rep. Ser., 1966, 339

    2 Tenth Report of the Joint FAO/WHO Expert Committee on Food
    Additives, FAO Nutrition Meetings Report Series, 1967, in press; 


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


    SORBIC ACID

    Chemical names                Sorbic acid; 
                                  Trans, trans-2,4-hexadienoic acid

    Empirical formula             C6H8O2

    Structural formula

    

    Molecular weight              112.13

    Definition                    Sorbic acid after drying for 4 hours in
                                  a vacuum desiccator over sulfuric acid,
                                  contains not less than 99 per cent. of
                                  C6H8O2.

    Description                   Sorbic acid is a white, crystalline
                                  solid with a mildly acrid odour.

    Uses                          As an antimicrobial and fungistatic
                                  agent.

    Biological Data

    This additive was evaluated by the Joint FAO/WHO Expert Committee on
    Food Additives in its Sixth and Eighth Reports (FAO/WHO, 1962; 
    FAO/WHO, 1965). Since their publication some new experimental work has
    been carried out on this compound. This and other work not included in
    the previous reports is presented in this monograph.

    Biochemical aspects

         The metabolism of 1-14C-sorbic acid has been studied by
    Fingerhut et al. (1962); 85 per cent. of the activity was found in the
    expired CO2, 0.4 per cent. in the faeces, 2 per cent. in the urine as
    urea and CO2, 3 per cent. in internal organs, 3 per cent. in the
    skeletal muscles and 6.6 per cent. in the other parts of the carcass.
    No glycogen was formed from sorbic acid. Most of the activity was

    found in the subcutaneous fat deposits and in the lipids of the
    organs. There was a linear relationship between dose and oxidation
    rate; the half-life, of the oxidation was 40-110 minutes in the dose
    range from 60-1200 mg/kg body-weight. In a similar experiment on mice,
    also using 1-14 C-sorbic acid, these results were confirmed; 81 ± 10
    per cent. of the sorbic acid was oxidised to CO2, the dose given
    ranging from 40-3000 mg/kg body-weight.  About 7 per cent. of the
    activity was excreted as sorbic acid and 0.4 per cent. as trans,
    trans-muconic acid (Westöö, 1964).

    Long-term studies

         The feeding experiment on groups of 100 rats (50 males and 50
    females) given 0 and 5 per cent. sorbic acid was extended to the whole
    life-span of the first generation. The average life-span of the group
    receiving sorbic acid was 811 days for the males and 789 days for the
    females. In the control group the life-span of the males was 709 days
    and for the females 804 days, possibly suggesting protection by sorbic
    acid against lung infection. Autopsies were performed on all rats of
    the first generation that died during the experiment. There were no
    differences in the organ weight of the individual groups nor in the
    distribution of the causes of death. In each group (5 per cent. sorbic
    acid and controls) only 2 tumours were found. The animals of the
    second generation were sacrificed after 250 days of feeding sorbic
    acid. Examination of liver, kidney, heart and testes showed no
    abnormalities (Lang, 1962; Long et al., 1967).

    Evaluation

    (See potassium Sorbate)

    REFERENCES

    FAO/WHO (1962) FAO Nutrition Meetings Report Series No 31 Wld 
    Hlth Org. techn. Rep. Ser., 228

    FAO/WHO (1965) FAO Nutrition Meetings Report Series No. 38;
    Wld Hlth Org. techn. Rep. Ser., 309

    Fingerhut, M., Schmidt, B. & Lang, K.(1962) Biochem. Z., 335, 118

    Lang, K. (1962) Arzneimittelforsch., 10, 997

    Lang, K. et al. (1967) In preparation

    Westöö, E. (1964) Acta chem. scand., 18, 1373
    

    See Also:
       Toxicological Abbreviations
       Sorbic acid (ICSC)
       SORBIC ACID (JECFA Evaluation)