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 FUMARIC ACID Chemical names Trans-butenedioic acid; Trans-1,2-ethylenedicarboxylic acid Empirical formula C4H4O4 Structural formula HOOC - CH " CH - COOH Molecular weight 116.07 Definition Fumaric acid contains not less than 99 per cent. C4H4O4. Description Fumaric acid occurs as white odourless granules, or as a crystalline powder with a characteristic acid taste. Uses As an acidulant and flavouring agent. Biological Data Biochemical aspects Fumaric acid is a normal constituent of tissues as an intermediate in the tricarboxylic acid cycle. Distribution of fumaric acid in rat tissue has been studied by partition chromatography and it was found that blood contained 3 mg/l, brain tissue 150 mg/kg, kidney tissue 95 mg/kg, liver 78 mg/kg and muscle 23 mg/kg (Marshall et al., 1949). The laxative effect of fumarates was studied in mice by determining the dose which shortened the average time before soft faeces appeared after oral administration. 433.2 mg magnesium fumarate or 432 mg disodium fumarate shortened the average time by 40 per cent. If the appearance of charcoal marker was taken as a guide, 15 per cent. shortening of appearance time was effected by 843.6 mg magnesium fumarate or 640 mg disodium fumarate (Locke et al., 1942). Twenty-six constipated patients suffering from a variety of chronic diseases not involving the gastrointestinal tract were given oral doses, of 5-30 g sodium fumarate, a satisfactory bowel motion resulting in 18 patients. There was much variability of response to a given dose between patients and in the same individual. Doses above 15 g caused unpleasant side effects. No abnormalities were noted in urine or serum. non-protein nitrogen level (Bodansky et al., 1942). Acute toxicity Animal Route LD50 Reference (mg/kg body-weight) Rat oral (sod. fumarate) approx. 8 000 Levey et al., 1946 Rabbit oral (disod. fumarate) approx. 3 600 Locke et al., 1942 4 800 Weiss et al., 1923 Short-term studies Guinea-pig. Eight animals were maintained on a diet containing 0 per cent. and 10 on a diet containing 1 per cent. fumaric acid for one year without any adverse effect on growth. The second generation from four mated animals was treated similarly without any adverse effect noted regarding growth, fertility or lactation (Levey et al., 1946). Rabbit. Each of five rabbits received i.v. injections of 50-500 mg/kg sodium fumarate every second or third day for 10-32 days without any injurious effect an blood levels of non-protein nitrogen or creatinine, phenolsulfophthalein excretion, or kidney and liver histology (Bodansky et al., 1942). Six rabbits received twice weekly i.p. injections of 60 mg/kg body-weight of sodium fumarate over 17-29 weeks. Swelling and congestion of the thyroids and atrophy of testes, with low hyaluronidase content, were found (Arai & Suehiro, 1953). A further nine male rabbits received 60 mg/kg body-weight sodium fumarate every second day by i.p. injection for 150 days. By the end of the test period, gonadotropic activity of the serum, as well as oestrogenic activity, was detected. There was progressive testicular atrophy in all animals, resulting in disappearance of seminiferous epithelium and survival of Sertoli cells only. Chromophobe cells were increased in the pituitary (Arai et al., 1955). Fourteen rabbits were fed 320-2080 mg/kg body-weight of disodium fumarate daily for 28 days without any deaths. A further six rabbits received 2880-3680 mg/kg body-weight for 17 days with three deaths. Two rabbits were fed a daily diet containing 640 mg/kg body-weight for 36 days without consistent adverse effects on body-weight, haematology, non-protein nitrogen or creatinine levels, or histopathological findings (Locke, et al., 1942). In another experiment, four groups of 15 rabbits were fed diets containing 0 or 6.9 per cent sodium fumarate (equivalent to 5 per cent. fumaric acid) for 150 days. There were no significant differences from controls in bodyweight gain, food consumption, mortality rate, blood counts, blood sugar, non-protein nitrogen level and urine. Organ weights were not significantly different between the groups and histologic examination showed no adverse findings attributable to the diet. In particular, spermatogenesis and testicular structure were unaffected (Packman et al., 1963). Dog. Fumaric acid was fed to four groups of 6 young dogs at 0, 1, 3 and 5 per cent. of the diet for two years without adverse effect on bodyweight gain, development, haematology, blood sugar and urea levels, haemoglobin and urine. Organ weights and gross and histopathological examination of all principal organs and tissues revealed no effects attributable to the treatment (Harrisson & Abbott, 1962). Man. Seventy-five chronically disabled subjects ranging in age from 29-91 years received 500 mg fumaric acid daily for one year without any toxic manifestations in haemoglobin level, RBC and WBC, non-protein nitrogen level, creatinine level, bromosulfonphthalein excretion and phenolsulfonphthalein excretion (Levey et al., 1946). Long-term studies Rat. Eight groups of 14 weanling rats were kept on diets containing 0, 0.1 and 1.0 per cent. fumaric acid and 1.38 per cent. sodium fumarate for one year (half the groups) or two years. No adverse effect was noted on rate of weight gain, haemoglobin, blood picture, calcium balance as shown by bone histology, or on the histology of liver, kidney, spleen and stomach (Levey et al., 1946). In another experiment five groups of 12 male and 12 female rats were fed diets containing 0, 0.1, 0.5, 0.8 and 1.2 per cent. of fumaric acid for 2 years without toxic effects on growth or food consumption. A further four groups of 12 male rats were kept for 2 years on diets containing 0, 0.5, 1.0 and 1.5 per cent. fumaric acid. Only at the 1.5 per cent. level was there a very slight increase in mortality rate and some testicular atrophy. Gross and microscopic examination of major organs revealed no abnormalities and tumour incidence was not significantly different between the groups (Fitzhugh & Nelson, 1947). Comments Fumaric acid is a normal component of intermediary metabolism. A human intake of 500 mg per day over one year had no apparent deleterious effects. Gonadal effects in male animals were reported on intraperitoneal administration of high doses, and should be investigated further. Evaluation This is based on the rat, bearing in mind the 2-year study in the dog. Level causing no toxicological effect Rat. 1.2 per cent. = 12 000 ppm of fumaric acid in the diet, equivalent to 600 mg/kg body-weight per day. 1.38 per cent. = 13 800 ppm of sodium fumarate in the diet equivalent to 690 mg/kg body-weight per day. Man 500 mg per day, equivalent to 10 mg/kg body-weight per day. Estimate of acceptable daily intakes for man mg/kg body-weight Unconditional acceptance 0-6 Conditional acceptance 6-10 REFERENCES Arai, T. & Suehiro, S. (1953) Wakayama Med. Reps., 1, 35 Arai, T., Suehiro, S. & Okamoto, T. (1955) Wakayama Med. Reps., 2, 115 Bodansky, O., Gold, H. & Zabm, W. (1942) J. Amer. Pharm. Ass. Sci. Ed., 31 1 Fitzhugh, O. G. & Nelson, A. A. (1947) J. Amer. Pharm. Ass. Sci. Ed., 36 217 Hall, R. L. (1960) Food Techn., 14, 488 Harrisson, J. W. E. & Abbott, D. D. (1962) Unpublished report of LaWall and Harrisson Research Laboratories, submitted to WHO Innes, J. M. (1936) Biochem. J., 30, 2040 Levey, S., Lasichak, A. G., Brimi, R., Orten, J. M., Smyth, C. J. & Smith, A. H.(1946) J. Amer. Pharm. Ass. Sci. Ed., 35, 298 Locke, A., Locke, R. E., Schlesinger, H. & Carr, H. (1942) J, Amer. Pharm. Ass., 31 12 Marshall, L. M., Orten, J. M. & Smith, A. H. (1949) J. Biol. chem., 179, 1127 Packman, E., W., Abbott, D. D. & Harrisson, J. W. E. (1963) Toxicol. appl. Pharm., 5, 163 Weiss, J. M., Downs, C. R. & Corson, H. P. (1923) Ind. Eng. Chem., 15, 628
See Also: Toxicological Abbreviations Fumaric acid (ICSC) Fumaric acid (WHO Food Additives Series 6) FUMARIC ACID (JECFA Evaluation)