The biological data on octanal were 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 bw was established (FAO/WHO, 1967;
Since this previous review, new data have become available and
are included in this summary.
The unsubstituted aliphatic aldehydes are readily oxidized in the
body to the corresponding fatty acids (Williams, 1959; F.E.M.A.,
1974). Short and medium chain length fatty acids, including octanoic
acid, are oxidized primarily to CO2 and water (Scheig & Klatskin,
1968). Such oxidation takes place rapidly both in the liver and other
tissues (Geyer et al., 1951; Valdivieso & Schwabe, 1964). The series
of reactions involved in the degradation of the fatty acid chain have
been fully described (Deuel, 1957; F.E.M.A., 1974).
Animal Route ml/kg bw References
Rat oral 5.63 Opdyke, 1973
Rabbit dermal 6.35 Opdyke, 1973
In a 12-week feeding study on groups of 12 male and 12 female
weanling rats using a blend of six aliphatic aldehydes, providing an
estimated daily intake for octanal of 13 mg/kg bw (with a total intake
for the blend of 112 mg/kg), no adverse effects were observed in
appearance, behaviour, growth, food intake, efficiency of food
utilization, presence of sugar or albumin in the urine, blood
haemoglobin, liver and kidney weights, or gross pathology (Oser,
Octanal showed no adverse effects in the one available subchronic
The evaluation of octanal is based on the presumed in vivo
oxidation to the corresponding acid.
The evaluation of octanal is based on a short-term study, assumed
metabolic fate, and analogy with several structurally related esters,
alcohols, aldehydes and acids, which display consistent biological
properties over a wide range in the homologous series.
The previous conditional ADI was changed into a temporary ADI.
Level causing no toxicological effect
Rat: 13 mg/kg bw.
Estimate of temporary acceptable daily intake for man (ADI)
0-0.06 mg/kg bw.
FURTHER WORK OR INFORMATION
Required by 1981.
Adequate metabolic studies in several species.
Aurousseau, B. et al. (1972) Energy and nitrogen utilization of diets
containing caprylic, lauric, and myristic acids by growing rats,
Effect of intake level, Ann. Biol. anim., 12(2), 263-280
Deuel, H. J. jr (1957) The lipids, their chemistry and biochemistry.
Chapter III in Biochemistry, Biosynthesis, Oxidation, Metabolism
and Nutritional Value, New York, Interscience Publishers Inc.
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. (1974) Scientific literature review of aliphatic primary
alcohols, aldehydes, esters, and acids in flavor usage.
Published by the National Information Services under contract
with the Food and Drug Administration
Geyer, R. P. et al. (1951a) Extrahepatic lipid oxidation by the rat,
Fed. Proc., 10(1), 188-189
Opdyke, D. L. J. (1973) Fragrance raw materials monographs, Food
Cosmet. Toxicol., 11, 113-114
Oser, B. L. (1967) Unpublished report
Scheig, R. & Klatskin, G. (1968a) Hepatic metabolism of 2-Cl4 octanoic
and 1-Cl4 Palmitic acids. In: 40th fall meeting program of the
American Oil Chemists' Society: Symposium on medium chain
triglycerides, 2-5 October 1966, J. Am. Oil Chem. Soc.,
Valdivieso, V. D. & Schwabe, A. D. (1964) Effect of exclusion of
hepatic circulation on oxidation of octanoic acid in the rat,
Proc. Soc. Exptl. Biol. Med., 116(2), 290-292
Williams, R. T. (1959) Detoxication mechanisms, The metabolism and
detoxication of drugs, toxic substances and other compounds,
London, Chapman & Hall Ltd, 2nd ed.