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


    LINALOL

    90 per cent. and 95 per cent.

    Synonym             Linalool

    Chemical name       3,7-Dimethyl-1,6-octadien-3-ol

    Empirical formula   C10H18O

    Structural formula  (CH3)2C=CHCH2CH2C(CH3)(OH)CH=CH2

    Molecular weight    154.25

    Definition          Linalol, 90 per cent. contains not less than 90
                        per cent. C10H18O. Linalol, 95 per cent.
                        contains not less than 95 per cent. C10H18O.

    Description         Linalol is a naturally occurring terpene alcohol
                        found in the volatile oils obrtained from various
                        flowers, fruits, grasses, leaves, roots, seeds,
                        and woods. It has been obtained from a number of
                        these oils.  It may be prepared by a
                        fractionation of saponified Brazilian Bois de
                        Rose oil. Commercial synthetic linalol has been
                        prepared by isomerization of geraniol and by
                        other methods.

    Biological Data

    Biochemical aspects

         This alcohol is probably converted to geraniol which metabolises
    to 1,5-dimethyl-1,5-hexadien-1,6-dicarboxylic acid, and
    7-carboxy-3-methylocta-6-enoic acid (Patty, 1963).

    Acute toxity

                                                                       

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

    Rat         oral        2790                   Jenner et al., 1964
                                                                       

    Short-term studies

         Rat. In a 12-week feeding study on 15 males and 15 females
    using mixed alcohols there was slight retardation of growth in male
    rats at 50 mg/kg body-weigt/day, without effect on food efficiency
    (Oser, 1967).

    Long-term studies

         None available.

    Comments

         Despite the scanty biochemical information evaluation can be
    based on the available animal data. Further biochemical and metabolic
    studies are needed.

    EVALUATION

    Estimate of acceptable daily intake for man

                                         mg/kg body-weight

         Conditional acceptance               0-0.25

    Further work required

         Biochemical and metabolic studies in animals and man and
    long-term studies.1

    REFERENCES

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

    Oser, B. L. (1967) Unpublished report

    Patty, F. A. (1963) Industrial Hygiene & Toxicology,  Vol. II,
    Interscience, London and New York

                   

    1 When considering the group of flavouring substances citral, 
    citronellol, linalol, linalyl acetate and geranyl acetate, the
    Committee stressed the urgent need to elucidate the metabolic pathways
    which may be common to these widely distributed substances. They found
    it reasonable to require that one or more of these substances should
    be made the subject of long-term studies. Whether this limitation can
    be made and which substances should be chosen may follow from a
    consideration of the biochemical evidence when this becomes available.
    

    See Also:
       Toxicological Abbreviations