EUGENOL Explanation Eugenol was reviewed at the eleventh meeting of the FAO/WHO Joint Expert Committee on Food Additives, specifications were prepared and a conditional ADI of 0-5 mg/kg bw was established (Anon. 1967). Since the previous review, new data have become available and are included in this summary. BIOLOGICAL DATA BIOCHEMICAL ASPECTS Intraperitoneal injection of a single 450 mg/kg dose of 14C methoxy labelled eugenol resulted in rapid distribution to all organs. Both ether and water soluble materials were recovered from most tissues and excretions. Only 0.2-1.0% of the dose was eliminated as expired 14CO2 (Weinberg et al., 1972). Over 70% of a lethal dose of eugenol was recovered on death, from the urine of rabbits (Schroder & Vollmer, 1932). Administration of single 200 mg doses to rats led to increased urinary output of ethereal glucuronides of 33-35 mg/rat in 12 hours compared to a control value of 4 mg/rat. Ester glucuronide values were unchanged (Yuasa, 1974). Incubation of eugenol with rat liver epithelial cells resulted in production of 4-(2'-3'-dihydroxy)propyl-2-methoxyphenol (Janiaud, 1936). The pharmacologic effects of eugenol include the previously reviewed inhibition of ß-D-glucosiduronic acid conjugation in rats receiving 150 mg/animal (Hartiala et al., 1966). Hydroxylating activity of liver homogenate on dimethylaminopyrine or hexobarbital was depressed in tissue from mice dosed with 160 mg/kg and sacrificed after one hour (Jaffe et al., 1968). Eugenol had no effect on aminopyrine-N-demethylation activity in the liver of rats given about 10% of the LD50 three times daily for 2-2/3 days. There was a slight decrease in hexobarbital lateral deflection time and in urinary ascorbic acid content (Gruebner, 1972). Other effects include: Animal Dose Route Effect Reference Dog ca. 50 mg/kg i.v. Choleresis Chabrol, 1931 Mice 100-350 mg/kg i.p. Reduction in Caujolle & rectal Meynier, 1960 temperature Mice 50 mg/kg i.p. Increase in Seto, 1969 sleeping time pentobarbital -131% ethanol-120% Rat 100 mg/kg i.p. No effects on deMello et al., spontaneous 1973 motor activity 160 mg/kg i.p. Severe depression and paralysis of hind quarters 200 mg/kg i.p. Catatonia Frog 0.1-100% direct Blockage of Kozam, 1977 exposure transmission of nerve of evoked impulses in exposed sciatic nerve TOXICOLOGICAL STUDIES Special studies on mutagenicity Eugenol was negative in a salmonella assay employing four mutant strains (TA 1530, TA 1531, TA 1532, TA 1964) both directly and after the use of mouse liver postmitochondrial fraction for activation. It was also inactive in a host-mediated assay (Green & Savage, 1978). Acute toxicity Animal Route (mg/kg bw) References Mouse Oral 3 000 Jenner et al., 1964 i.p. 500 Caujolle & Meynier, 1960 i.p. 630 Fujii et al., 1970 Rat Oral 1 930 Sober et al., 1950 Oral 2 680 Taylor et al., 1964 Guinea-pig Oral 2 130 Jenner et al., 1964 The acute toxic effects include desquamation of the gastric mucosa (Hitchcock, 1952), and punctate haemorrhages in dogs (Hartiala et al., 1966), gastric inflammation and depression of secretory capacity (Sobers 1950), liver discoloration and mottling in rats (Taylor et al., 1964) liver congestion in dogs (Lauber & Hollander, 1950). Subchronic studies Ten male and 10 female rats given 89.7 mg/kg eugenol for 12 weeks showed no adverse effects (Trubek Laboratories, 1958). Twenty male rats were given increasing doses from 1400 to 4000 mg/kg bw for 34 days. There was considerable mortality, slight liver enlargement and adrenal enlargement. Histology showed enlarged liver cells. The forestomach showed moderately severe hyperplasia and hyperkeratosis of the stratified squamous epithelium with focal ulceration (Hagan et al., 1965). In another study groups of 10 males and 10 females were fed diets containing 0, 0.1 and 1.0% eugenol for 19 weeks without any adverse effect on growth rate, haematology, organ weights and histology of major tissues (Hagan et al., 1967). Special studies on carcinogenicity In ingestion and injection studies in progress, eugenol-treated mice have shown no effects different from the control groups (Miller, 1979). In a study not meeting current standards, eugenol did not potentiate the tumorigenic effects of methylcholanthrene (Hitchcock, 1952). In the United States of America, the NCI has a carcinogenicity study in rats and mice under way. Comments High doses are hepatotoxic to dogs and rats. The short-term studies provide some basis for toxicological evaluation. The data on metabolites are incomplete but suggest no special concern. Various mutagenicity tests gave negative results. Carcinogenicity studies are in progress. EVALUATION Level causing no toxicological effect Rat: 1% in the diet equivalent to 500 mg/kg bw Estimate of temporary acceptable daily intake for man 0-2.5 mg/kg bw FURTHER WORK OR INFORMATION Required by 1982 Completion of ongoing carcinogenic studies. REFERENCES Anon. (1978) Scientific Literature Review of Eugenol and Related Substances in Flavor Usage Anon. (1967) Toxicological Evaluation of Some Flavouring Substances and Non-Nutritive Sweetening Agents; FAO Nutrition Meetings, Report Series No. 44A, WHO/FAO Add./68.33 Cambel, P., Sgouris, J. T. & Conray, C. E. (1952) Effects of Histamine and eugenol on gastric mast cell diapedesis and leucopedesis in the albino rat, W. J. Fla. Acad. Sc., 15, 147-148 Caujolle, F. & Maynier, D. (1960a) Hypothermic activity in the eugenol and safrole series, Ann. Pharm. Fr., 18, 601-612 Chabrol, E. et al. (1931) Cholagog action of guaiacol derivatives, C. R. Soc. Biol., 107, 1240-1243 de Mello, C. A. et al. (1973) Behavioral observations on compounds found in nutmeg, Psychopharmacologia, 31 (4), 349-363 Fujii, K. et al. (1970) Structure-activity relations for methylenedioxy-phenyl and related compounds on hepatic microsomal enzyme function, as measured by prolongation of hexobarbital narcosis and zoxazolamine paralysis in mice, Toxicol. Appl. Pharmacol., 16, 482-494 Goeransson, K. et al. (1967) Some cases of eugenol hypersensitivity, Sven. Tandiak. T., 60, 545-549 Green, N. R. & Savage, J. R. (1978) Screening of safrole, eugenol, their ninhydrin positive metabolites and selected secondary amines for potential mutagenicity, Mutation Research, 57, 115-121 Gruebner, I., Klinger, W. & Ankermann, H. (1972) Various substances and substance classes with inducer properties. II. Arch. Int. Pharmacodyn. Ther., 196 (2), 288-297 Hagan, E. C. et al. (1965) Toxic properties of compounds related to safrole, Toxicol. Appl. Pharmacol., 7 (1), 18-24 Hagan, E. C. et al. (1967) Food flavorings and compounds of related structure. II. Subacute and chronic toxicity, Food Cosmet. Toxicol., 5 (2), 141-157 Hartiala, K. J. W., Pulkkinen, M. & Ball, P. (1966) Inhibition of beta-D-glucosiduronic acid conjugation (rat and guinea pig) by eugenol, Nature, 210 (5037), 739-740 Hitchcock, C. R. (1952) Failure of eugenol and heat to potentiate gastric tumor induction by 20-methylcholanthrene in mice, J. Natl. Cancer Inst., 12 (4), 723-733 Jaffe, H. et al. (1968) In vivo inhibition of mouse liver microsomal hydroxylating systems by methylenedioxyphenyl insecticidal synergists and related compounds, Life Sci., 7 (19), 1051-1062 Janiaud, P. et al. (1976) Comparative study in rat liver cell culture of the metabolism of different analogs and metabolites of a natural hepatocancerogen; safrole, Meeting of the Biol. Soc. Dijon Jenner, P. M. et al. (1964) Food flavorings and compounds of related structure. I. Acute oral toxicity, Food Cosmet. Toxicol., 2 (3), 327-343 Kozam, G. (1977) The effect of eugenol on nerve transmission, Oral Surg., 44, 799 Lauber, F. U. & Hollander, F. (1950) Toxicity of the Mucigogue, eugenol, administered by stomach tube to dogs, Gastroenterol., 15 (3), 481-486 Miller, J. A. (1979) Personal communication, February 16 Mortenson, H. (1969) Case of allergic stomatitis due to eugenol, Tandlaegebladet, 72, 1155-1158 Schroder, V. & Vollmer, H. (1932) The excretion of thymol, carvacrol, eugenol and guaiacol and the distribution of these substances in the organism, Arch. Exp. Path. Pharmakol., 168, 331-353 Seto, T. A. Keup. (1969) Effects of Alkylmethoxybenzene and Alkylmethylene-dioxybenzene essential oils on pentobarbital and ethanol sleeping time, Arch. Int. Pharmacodyn. Ther., 180 (1), 232-240 Sober, H. A., Hollander, F. & Sober, E. K. (1950) Toxicity of eugenol: Determination of LD50 on rats, Proc. Soc. Exp. Biol. Med., 73 (1), 148-151 Sober, H. A., Hollander, F. & Sonnenblick, B. P. (1950) Response of gastric mucous barrier in pouch dogs to repeated topical application of eugenol, Am. J. Physiol., 162 (1), 120-130 Taylor, J. M., Jenner, P. M. & Jones, W. I. (1964) A comparison of the toxicity of some allyl, propenyl and propyl compounds in the rat, Toxicol. Appl. Pharmacol., 6 (4), 378-387 Trubeck Laboratories (1958) Unpublished report. Toxicological screening of components of food flavors. Class IX. Aromatic aldehydes (Eugenol). Weinberg, J. E. et al. (1972) (14C)-eugenol. I. Synthesis, polymerization, and use, J. Dent. Res., 51 (4), 1055-1061 Yuasa, A. (1974) Exp. studies on glucuronidation. III. Jpn. J. Vet. Sci., 36 (5), 427-432
See Also: Toxicological Abbreviations Eugenol (FAO Nutrition Meetings Report Series 44a) Eugenol (WHO Food Additives Series 17) EUGENOL (JECFA Evaluation) Eugenol (IARC Summary & Evaluation, Volume 36, 1985)