ALPHA-IONONE
Explanation
Alpha-Ionone was reviewed at the eleventh meeting of the Joint
FAO/WHO Expert Committee on Food Additives, specifications were
prepared, and a conditional acceptable daily intake for man (ADI) of
0-0.1 mg/kg body weight was established (FAO/WHO, 1967; FAO/WHO,
1968).
Since this previous review, new data have become available and
are included in this monograph.
BIOLOGICAL DATA
BIOCHEMICAL ASPECTS
Following oral administration, alpha-ionone undergoes biochemical
oxidation in the rabbit and is excreted in the urine, principally, as
5-oxo-cis-tetrahydro-ionone, indicating in vivo oxidation of carbon
atom 5 in the ionone structure (Prelog & Wursch, 1951).
TOXICOLOGICAL STUDIES
Acute toxicity
LD50 References
Animal Route mg/kg body weight
Mouse i.p. 2 277 (Sporn et al., 1963)
Mouse s.c. 2 605 (Wenzel & Ross, 1957)
Rat Oral 4 590a (Jenner et al., 1964)
a Test material identified as 60% alpha-ionone and 40% ß-ionone.
Short-term studies
Rat
Groups of 10 male and 10 female rats were maintained for 17 weeks
on diets containing "Ionone Standard" (60% alpha-ionone and 40%
ß-ionone) at levels of 0, 1000, 2500, and 10 000 ppm (approximately
equivalent to 50, 125, and 500 mg/kg body weight). No adverse effects
were observed on growth, appearance, food intake, haematology, final
body weight, organ weights or macroscopic appearance of organs of rats
on all levels of "Ionone Standard" in the diet. However, microscopic
examination revealed swelling of the hepatic parenchymal cells at all
dietary levels. This "swelling of parenchymal cells" was dose-
dependent, being "slight to moderate" at the highest dietary level
(10 000 ppm), "slight" at the intermediate level (2500 ppm), and "very
slight" at the lowest level (1000 ppm) (Hagan et al., 1967).
Comments
The evaluation of alpha-ionone is based on the previous
evaluation of the eleventh Expert Committee. The previous conditional
ADI was converted to a temporary ADI.
EVALUATION
Estimate of temporary acceptable daily intake for man
0-0.05 mg/kg bw.
FURTHER WORK OR INFORMATION
Required by 1980.
(1) An additional short-term toxicity study (90 days) on a well-
characterized sample of alpha-ionone with one dietary level comparable
to those at which minimal effects were previously observed.
(2) Metabolic studies.
REFERENCES
FAO/WHO (1967) Toxicological evaluation of some flavouring substances
and non-nutritive sweetening agents, FAO Nutrition Meetings
Report, Series No. 44a; WHO/Food Add./68.33
FAO/WHO (1968) Specifications for the identity and purity of food
additives and their toxicological evaluation: some flavouring
substances and non-nutritive sweetening agents, Eleventh Report
of the Joint FAO/WHO Expert Committee on Food Additives, FAO
Nutrition Meetings Report Series No. 44, Wld Hlth Org. techn.
Rep. Ser. No. 383
F.E.M.A. (1976) Scientific literature review of alicyclic compounds
of carbon, hydrogen and oxygen in flavour usage, published by the
National Information Services under contract with the Food and
Drug Administration
Hagan, E. C. et al. (1967) Food flavourings and compounds of related
structure: II. Subacute and chronic toxicity, Food Cosmet.
Toxicol., 5, 141-157
Jenner, P.M. et al. (1964) Food flavourings and compounds of related
structure. I. Acute oral toxicity, Food Cosmet. Toxicol., 2,
327-343
Prelog, V. & Wuersch, J. (1951) Organ extracts and urine. 21. The
biochemical oxidation of alpha-ionone in the animal body. Helv.
Chim. Acta, 34(3), 859-861 (in German)
Sporn, A. et al. (1963) The toxicity of butyl acetate, methyl naphthyl
ketone, and ionone, Igiena (Bucharest), 12(5), 437-446
Wenzel, D. G. & Ross, C. R. (1957) Central stimulating properties of
some terpenones, J. Am. Pharm. Assoc., 46, 77-82