FAST GREEN FCF EXPLANATION Fast Green FCF was evaluated at the twenty-fifth meeting of the Committee (Annex 1, reference 56) when inadequacies were identified in earlier long-term feeding studies in rats and mice. The previously- allocated ADI was converted to a temporary ADI of 12.5 mg/kg b.w. pending the results of adequate long-term feeding studies and multigeneration reproduction/teratogenicity studies. Since the previous evaluation, additional data have become available and are summarised and discussed in the following monograph. The previously-published monograph has been expanded and is reproduced in its entirety below. BIOLOGICAL DATA Biochemical aspects Rats and dogs were given orally 200 mg of the colour. In the rats the urine and faeces were collected for 36 hours. In the dogs, a bile fistula was made for bile analysis. Almost all the administered colour was excreted unchanged in the faeces of rats. No colour was found in the urine. In the bile of the dogs, the amount of colour never exceeded 5% of the given dose. After feeding, the colour was found in the bile of rats and rabbits, but not in their urine. It was concluded that the quantity found in the bile provides a reasonable estimate of the amount absorbed from the gastrointestinal tract (Hess & Fitzhugh, 1953; 1954; 1955). Following i.v. injection in rats, over 90% of the colour was excreted in the bile within 4 hours (Iga et al., 1971). Fast Green FCF was found to have a high binding affinity for plasma protein (Gangolli et al., 1967; 1972; Iga et al., 1971). Toxicological studies Special studies on carcinogenicity (see also long-term studies) Mice Groups of 60 (120 controls) male and female Charles-River CD-1 mice were fed diets containing 0, 0.5, 1.5, or 5.0% Fast Green FCF from 43 days of age for approximately 24 months. Ten animals/sex/group were subjected to haematological examination at 3, 6, 12, and 18 months. All animals dying or killed in a moribund condition and all survivors to termination were subjected to detailed post-mortem examination. The following tissues were examined histologically from all survivors from the control and 5%-dose groups as well as all animals dying or killed in extremis from these groups: adrenals, aorta, bone and marrow (femur), brain (3 sections), eyes (with optic nerve), gall bladder, gastrointestinal tract (oesophagus, stomach, duodenum, ileum, caecum, colon), heart, kidneys, liver, lung, lymph nodes (mesenteric and mediastinal), mammary gland, nerve (sciatic), ovaries, pancreas, pituitary, prostate, salivary gland, seminal vesicles, skeletal muscle, skin, spinal cord, spleen, testes with epididymides, thymus, thyroid/parathyroid, trachea, urinary bladder, uterus, and gross lesions/tissue masses. In addition, gross changes/tissue masses were examined histologically from all animals in the lower-dose groups. No treatment-related effects on mortality were observed. The mean body weights of females in the 5%-dose group were consistently lower than controls and the mean body weights of males in the 5%-dose group were lower than controls at weeks 52 and 78. No other consistent differences in body weight were noted. Slight reductions in haemoglobin, haematocrit, and erythrocyte counts were noted in the high-dose males at 18 months but no other consistent or dose-related haematological changes were observed. Histological examination did not reveal any treatment-related lesions and the incidence, origins, and histology of benign and malignant neoplasms did not differ significantly between controls and treated animals (Hogan & Knezevich, 1981). Rats Eighteen weanling Osborne-Mendel rats of both sexes received weekly s.c. injections of approximately 30 mg (1 ml of a 3% aqueous solution) of Fast Green FCF for 94-99 weeks. Subcutaneous fibrosarcomas appeared at the site of injection in 15 animals (Nelson & Hagan, 1953; Hansen et al., 1966). Two groups of 16 female rats (control groups of 10 rats) were given s.c. injections of 0.5 ml of a 3% or 6% solution (the rats received with each injection 15 or 30 mg, respectively). The colour used in the experiment was certified as 92% pure and was supplied as the disodium sulfonate salt. The 10 control rats were given distilled water injections. At first, injections of 6% were given 3 times a week; after 17 weeks it became necessary to reduce the dose to 3%. Thereafter, both groups were given injections of 3% twice weekly for 9 weeks. The rest of the time, 22 weeks, both groups were injected usually once a week, while occasionally 2 injections were tolerated. Growth inhibition was observed. Thirteen out of 16 animals receiving 6% of the colour had fibrosarcomas. The animals given 3% also showed fibrosarcomas (10 out of 12). The controls did not show neoplastic tissue at the site of injection (Hasselbach & O'Gara, 1960). Subcutaneous injection of 1 ml of an 0.8% solution twice weekly produced histological changes suggestive of subsequent sarcoma formation unassociated with chemical carcinogenic potential (Grasso & Golberg, 1966). No tumours were produced in 11 hamsters injected with 1 mg of the dye in 0.1 ml water (Price et al., 1978). A carcinogenicity study with an in utero phase was carried out in Charles-River albino rats. Groups of 60 (120 controls) male and female rats of the F0 generation were fed diets containing 0, 1.25, 2.5, or 5.0% Fast Green FCF for 2 months prior to mating and throughout gestation and lactation. Following the reproductive phase, a maximum of 4 animals of each sex/litter were randomly selected from the F1 generation for the long-term carcinogenicity study. Groups of 70 animals of each sex/group were given Fast Green FCF in the diet at the same concentrations as the parent generation. An interim kill of 10 animals of each sex per group was carried out after 12 months; the remaining animals continued to receive the test diets for 29 months (males) or 31 months (females). Haematology, clinical chemistry tests, and urinalysis were performed on 10 rats of each sex/group at 3, 6, 12, 18, and 24 months. Gross autopsies were performed on all animals that died on test or were killed in a moribund condition and on all F1 generation animals at interim and terminal sacrifice. The following tissues were examined histologically from all animals killed at interim sacrifice and all survivors from the control and 5%-dose groups, as well as all animals dying or killed in extremis from these groups: adrenals, aorta, bone and marrow (femur), brain (3 sections), eyes (with optic nerve), gastrointestinal tract (oesophagus, stomach, duodenum, ileum, caecum, colon), heart, kidneys, liver, lung, lymph nodes (mesenteric, mediastinal) mammary gland, nerve (sciatic), ovaries, pancreas, pituitary, prostate, salivary gland, seminal vesicles, skeletal muscle, skin, spinal cord, spleen, testes with epididymides, thymus, thyroid/parathyroid, trachea, urinary bladder, uterus, and gross lesions/tissue masses. In addition, gross changes/tissue masses were examined histologically from all animals in the lower-dose groups. Subsequently, the urinary bladder from males of the 1.25- and 2.5%-dose groups were also examined histologically. During the premating period, no treatment-related effects were seen on mortality or body-weight gain but there was a dose-related increase in food consumption. After mating there were no treatment- related effects on the number of successful pregnancies or pup viability at birth, but pup mortality was increased in the 5%-dose group during the period 4-14 days of lactation. Mean pup weight was reduced in all treated groups, most markedly in the high-dose group. In the F1 generation, mortality was slightly higher in all treated groups than in controls, but it did not vary in a dose-related manner. Mean body weights of the high-dose males were consistently lower than controls, even though their food intake was elevated. Fasting blood glucose levels were elevated in females in all treated groups at 3 and 12 months, females in the 1.25 and 2.5% groups at 18 months, and males in all treated groups at 12 and 18 months. At interim (12 months) sacrifice, the mean absolute and relative thyroid weights were elevated in the high-dose males while the relative kidney weights were elevated in the high-dose females. At termination, the thyroid weights were elevated in males of the 2.5- and 5%-dose groups and females of the 5% group; kidney weights were elevated in both sexes of the 5%-dose group and females of the 2.5% group. No treatment-related effects were seen in urinalyses, haematology determinations, physical observations, or ophthalmology. Histopathological examination revealed an increased incidence of urothelial hyperplasia in treated males and of urinary bladder transitional cell/urothelial neoplasms in males of the 5%-dose group. The overall incidences in males are summarized below: Group Control Control 1.25% 2.5% 5% 1 2 Number examined 58 61 58 55 60 Number with neoplasia 1 2 1 2 5 Number with hyperplasia 1 4 7 10 3 Non-statistically-significant increases in testicular Leydig cell tumours and neoplastic nodules in the liver were also observed. When time-to-tumour analysis was performed on pathology incidence data, the increased incidence of bladder tumours was confirmed and the incidence of several other tumour types showed statistically-significant differences related to treatment, including neoplastic nodules in the liver (males and females), female mammary adenomas and pituitary adenomas, male parthyroid adenomas, male thyroid medullary carcinomas, female uterine leiomyosarcomas, and male testicular interstitial/Leydig cell tumours. Of the non-neoplastic pathology, chronic nephropathy was a common finding in all groups but the severity was greater in females in the 5%-dose group. Other lesions did not appear to be related to treatment (Knezevich & Hogan, 1981). Special studies mutagenicity Fast Green FCF was non-mutagenic in the Salmonella/microsome assay (Brown et al., 1978) and negative results were also obtained in bacterial DNA repair tests (Kada et al., 1972; Rosenkranz & Leifer, 1980). The colour was inactive in a gene conversion assay in diploid yeast (Sankaranarayanan & Murthy, 1979). In one of 2 experiments, colour-induced cell transformation occurred in cultured Fisher rat embryo cells at a concentration of 1 µg/ml (Price et al., 1978) and chromosome damage was reported in an in vitro test using Chinese hamster ovary cells (Au & Hsu, 1979). Special studies on reproduction Rats A 3-generation reproduction study was carried out on Fast Green FCF in Long-Evans rats at dose levels of 0, 10, 100, 300, or 1,000 mg/kg b.w./day. The first generation parents (10 males, 20 females) were given the appropriate dose of Fast Green FCF in the diet 2 weeks before the first mating, and dosing continued throughout the gestation, lactation, and post-weaning phases for three successive generations. The F0 generation rats were mated twice, the F1a litters being necropsied at weaning, and selected animals (10 males, 20 females) from the F1b litters were used for breeding. Following an 80-day growth period, animals from the F1b generation were mated 3 times and the offspring of the F2a and F2b generations were treated identically to the F1a and F1b generations. Following the third mating, half of the pregnant dams were sacrificed on day 19 of gestation, the uterine contents were examined for total embryos/resorption sites, and the corpora lutea per ovary were recorded. The other half were allowed to deliver normally (F2c) and were sacrificed at weaning. The F2b animals were mated once and allowed to raise their offspring to weaning when both parents and offspring were culled. Gross necropsies were performed on all parent animals and on F1a, F2a, F2c, and F3a offspring at weaning. Selected tissues from 5 animals of each sex/dose from the F1b parents and the F3a generation at weaning were fixed at necropsy, and the following tissues examined histologically from the control and high-dose group: stomach, ileum, jejunum, colon, liver, spleen, heart, lungs, adrenals, kidneys, urinary bladder, thyroid, ovaries, and uterus or testes. No effects attributable to treatment were observed with respect to food consumption, body weight, adult mortality, mating performance, pregnancy and fertility rates, gestation length, offspring survival, weights and sex, litter survival, resorption rates, or necropsy findings. There were no macroscopic or microscopic tissue abnormalities of either F1b- or F3a-generation animals considered to be attributable to treatment (Smith, 1973). Acute toxicity LD50 Species Route (mg/kg b.w.) Reference Rat Oral > 2,000 Lu & Lavallee, 1964 Dog Oral > 200 Radomski & mg/dog Deichman, 1956 Short-term studies Dogs Four beagles/group, equally divided by sex, were fed Fast Green FCF at 0, 1.0, or 2.0% of the diet for 2 years. Histopathology attributable to the colour was limited to green blobs of pigment in the renal cortical tubular epithelial cytoplasm of a male dog at the high-dose level; a female dog at the high-dose level showed slight interstitial nephritis and slight bone marrow hyperplasia (Hansen et al., 1966). Long-term studies Mice Groups of 50 male and 50 female C3HeB/FeJ mice were fed diets containing 1.0 or 2.0% Fast Green FCF for 2 years and 100 mice of each sex served as controls. After 78 weeks, 56 controls, 27 animals in the 1.0%-treatment group, and 17 animals in the 2.0%-treatment group still survived. Microscopic examination revealed no lesions that were attributed to feeding of the colour (Hansen et al., 1966). Rats Groups of 50 weanling Osborne-Mendel rats, evenly divided by sex, were fed diets containing 0, 0.5, 1.0, 2.0, or 5.0% colour for 2 years. No effects on growth or mortality were observed. Microscopic examination revealed no lesions that were attributed to the feeding of the colour (Hansen et al., 1966). The colour was fed at a dietary level of 4.0% to 5 male and 5 female rats for periods from 18 to 20 months. This procedure resulted in gross staining of the forestomach, glandular stomach, small intestine, and colon. Granular deposits were noted in the stomach. No tumours were observed (Willheim & Ivy, 1953). Observations in man No data available. Comments The production of local sarcomata at the site of s.c. injection in rats is not considered to constitute evidence of carcinogenicity by the oral route. The mouse oral carcinogenicity study was negative but in the rat study, an increased incidence of urothelial hyperplasia and/or neoplasia of the bladder was observed. The biological significance of observed differences in benign and malignant tumours at other sites is questionable since, in some cases, statistically- significant differences were observed between the 2 control groups and, apart from the bladder, complete histological examination was not performed on the low- and intermediate-dose groups. Biochemical studies have shown that the colour is poorly absorbed and the 3-generation reproduction/teratogenicity study was uneventful. In view of the equivocal results of the most recent carcinogenicity study in rats, the evaluation is based on the earlier study, pending complete histological examination of all groups of rats and biometric examination of the data. EVALUATION Level causing no toxicological effect Mouse: 5% in the diet equal to 18,600 mg/kg b.w./day falling to 8,000 mg/kg b.w./day. Rat: 5% in the diet equivalent to 2,500 mg/kg b.w./day. Estimate of temporary acceptable daily intake for man 0-12.5 mg/kg b.w. Further work or information Required by 1986 Complete histological examination of all dose-groups in the long- term carcinogenicity feeding-study in the rat and biometric examination of the data. REFERENCES Au, W. & Hsu, T.C. (1979). Studies on clastogenic effects of biologic stains and dyes, Environmental Mutagenesis, 1, 27. Brown, J.P., Roehm, G.W., & Brown, R.J. (1978). Mutagenicity testing of certified food colours and related azo, xanthene and triphenylmethane dyes with the Salmonella/microsome system, Mutation Res., 56, 249-271. Gangolli, S.D., Grasso, P., & Golberg, L. (1967). Physical factors determining the early local tissue reactions produced by food colourings and other compounds injected subcutaneously. Fd. Cosmet. Toxicology., 5, 601-621. Gangolli, S.D., Grasso, P., Golberg, L., & Hooson, J. (1972). Protein binding by food colourings in relation to the production of subcutaneous sarcoma. Fd. Cosmet. Toxicology., 10, 449-462. Grasso, P. & Golberg, L. (1966). Subcutaneous sarcoma as an index of carcinogenic potency. Fd. Cosmet. Toxicology., 4, 297-320. Hansen, W.H., Long, E.L., Davis, K.J., Nelson, A.A., & Fitzhugh, O.G. (1966). Chronic toxicity of three food colourings: guinea green B, light green SF yellowish, and fast green FCF in rats, dogs and mice, Fd. Cosmet. Toxicology., 4, 389-410. Hess, S.M. & Fitzhugh, O.G. (1953). Metabolism of coal-tar dyes. I. Triphenylmethane dyes. Fed. Proc., 12, 330-331. Hess, S.M. & Fitzhugh, O.G. (1954). Metabolism of coal-tar dyes. II. Bile studies. Fed. Proc., 13, 365. Hess, S.M. & Fitzhugh, O.G. (1955). Absorption and excretion of certain triphenylmethane colours in rats and dogs, J. Pharmacol. Exp. Ther., 114, 38-42. Hesselbach, M.L. & O'Gara, R.W. (1960). Fast green and light green induced tumours: induction, morphology and effect on host. J. Nat. Cancer Inst., 24, 769-793. Hogan, G.K. & Knezevich, A.L. (1981). A long-term oral carcinogenicity study of FD&C Green No. 3 in mice. Unpublished report No. 77-1781 from Bio/dynamics Inc., East Millsone, NJ, USA. Submitted to WHO by Certified Color Manufacturers' Association. Iga, T., Awazu, S., & Nogami, H. (1971). Pharmacokinetic study of biliary excretion. II. Comparison of excretion behaviour in triphenylmethane dyes. Chem. Pharm. Bull., 19, 273-281. Kada, T., Tutikawa, K., & Sadaie, Y. (1972). In vitro and host mediated 'rec-Assay' procedures for screening chemical mutagens; and phloxine, a mutagenic red dye detected. Mutation Res., 16, 165-174. Knezevich, A.L. & Hogan, G.K. (1981). A long-term oral toxicity/ carcinogenicity study of FD&C Green No. 3 in rats. Unpublished report No. 77-1780 from Bio/dynamics Inc., East Millstone, NJ, USA. Submitted to WHO by Certified Color Manufacturers' Association. Lu, F.C. & Lavallee, A. (1964). The acute toxicity of some synthetic colours used in drugs and food. Canad. Pharm. J., 97, 30. Nelson, A.A. & Hagan, E.C. (1953). Production of fibrosarcomas in rats at site of subcutaneous injection of various food dyes. Fed. Proc., 12, 397-398. Price, P.J., Suk, W.A., Freeman, A.E., Lane, W.T., Peters, R.L., Vernon, M.L., & Huebner, R.J. (1978). In vitro and in vivo indications of the carcinogenicity and toxicity of food dyes. Int. J. Cancer, 21, 361-367. Radomski, J.L. & Deichman, W.B. (1956). Cathartic action and metabolism of certain coal tar food dyes. J. Pharmacol. Exp. Ther., 118, 322-327. Rosenkranz, H.S. & Leifer, Z. (1980). In Chemical Mutagens: Principles and Methods for their Detection. Ed: de Serres, F.J., & Hollaender, A. Plenum Press; New York & London, Vol. 6, p. 109. Sankaranarayanan, M. & Murthy, M.S.S. (1979). Testing of some permitted food colours for the induction of gene conversion in diploid yeast. Mutation Res., 67, 309-314. Smith, J.M. (1973). A three generation reproduction study of FD&C Green No. 3 in rats. Unpublished report No. 71R-736 from Bio/dynamics Inc., East Millstone, NJ, USA. Submitted to WHO by Certified Color Manufacturers' Association. Willheim, R. & Ivy, A.C. (1953). A preliminary study concerning the possibility of dietary carcinogenesis. Gastroenterology, 23, 1-19.
See Also: Toxicological Abbreviations Fast green FCF (FAO Nutrition Meetings Report Series 46a) Fast Green FCF (WHO Food Additives Series 16) Fast Green FCF (WHO Food Additives Series 21) FAST GREEN FCF (JECFA Evaluation) Fast Green FCF (IARC Summary & Evaluation, Volume 16, 1978)