NTP Toxicology and Carcinogenesis Studies of D&C Yellow No. 11 (CAS No. 8003-22-3) in F344/N Rats (Feed Studies).
D&C Yellow No. 11 is used to color topical drug preparations and cosmetics. It is also used in spirit lacquers, polystyrenes, polycarbonates, polyamides, acrylic resins, colored smokes, and hydrocarbon solvents. D&C Yellow No. 11 was nominated to the NTP for toxicity and carcinogenesis studies as part of a larger regulatory effort mandated by Congress and undertaken by the Food and Drug Administration to determine the safety of a number of provisionally listed dyes. D&C Yellow No. 11 is currently regulated for external use. The recommendation to study D&C Yellow No. 11 by dietary exposure was based on the fact that it is a contaminant of D&C Yellow No. 10, a candidate for permanent listing as a chemical for which there is a potential for ingestion. First-generation (F(0)) male and female F344/N rats were given D&C Yellow No. 11 (approximately 99% pure) in feed for up to 19 weeks and then mated, and exposure of second-generation (F(1)) males and females began in utero and continued for 2 years after weaning at 28 days of age. Genetic toxicology studies were conducted in Salmonella typhimurium, cultured Chinese hamster ovary cells, and mouse peripheral blood. REPRODUCTIVE TOXICITY STUDY: Groups of 60 male and 60 female F(0) rats were given 0, 500, 1,700, or 5,000 ppm D&C Yellow No. 11 in feed for up to 19 weeks, which resulted in average daily doses of 35, 120, or 350 mg D&C Yellow No. 11/kg body weight to males and 35, 120, or 370 mg/kg to females. All F(0) males and females survived until the end of the study. Prior to cohabitation, mean body weight gains of males given 500, 1,700, or 5,000 ppm and of females given 5,000 ppm were significantly lower than those of the controls. The mean body weight gains of exposed females during gestation and lactation were generally similar to those of the controls. Feed consumption by exposed groups of rats was generally similar to that by the control groups prior to cohabitation. The duration of gestation, the average litter size, the number of live pups on days 4 (precull) and 21, and the percentage of male pups for each exposure group were similar to those of the controls. The mean body weights of exposed litters were significantly less than those of the control litters on days 14 and 21; this effect was considered to be related to D&C Yellow No. 11 exposure. 2-YEAR STUDY: Groups of 60 male and 60 female F(1) rats were given 0, 500, 1,700, or 5,000 ppm D&C Yellow No. 11 in feed for 105 (males) or 106 (females) weeks after weaning (day 28); 6 to 10 rats per group were evaluated at 12 months. These exposure concentrations resulted in average daily doses of approximately 25, 85, or 250 mg D&C Yellow No. 11/kg body weight to males and 25, 100, or 280 mg/kg to females. Survival, Body Weights, Feed Consumption, and Clinical Findings: Survival of males given 1,700 or 5,000 ppm was significantly less than that of the controls, and survival of 1,700 ppm females was significantly greater than that of the controls. Mean body weights of 1,700 and 5,000 ppm males and females were generally lower than those of the controls throughout the study. Feed consumption by exposed groups was similar to that by the controls. Chemical-related clinical findings included yellow discoloration of the entire body in all exposed males and females from day 1 and head swelling and edema in 1,700 and 5,000 ppm males. One 1,700 ppm and five 5,000 ppm males were moribund and were killed between weeks 49 and 81; these deaths were attributed to extensive edema. Hematology: A few minimal hematology changes occurred in male rats at the 12-month interim evaluation. There was evidence of minimal anemia in exposed males; this anemia was characterized by decreased hematocrit values, hemoglobin concentrations, and erythrocyte counts. The minimal anemia was characterized as normocytic, normochromic, and nonresponsive. There were no biologically or statistically significant differences in hematology parameters between control and exposed females. Pathology Findings: Absolute and relative liver weights of all exposed groups of md relative liver weights of all exposed groups of males and females were significantly greater than those of the controls at 12 months. At 2 years, the incidences of hepatocellular adenoma in 5,000 ppm males and of hepatocellular adenoma or carcinoma (combined) in 5,000 ppm females were significantly greater than those in the controls. At 12 months, the incidences of clear cell foci in 1,700 and 5,000 ppm females were significantly greater than that in the controls. At 2 years, the incidences of mixed cell foci in exposed males and of clear cell foci in exposed males (except 500 ppm) and females were significantly greater than those in the controls. Incidences of cytologic alterations (basophilia and granularity) of hepatocytes, and pigmentation in bile duct epithelium, hepatocytes, and Kupffer cells in exposed males and females were greater than those in the controls at both 12 months and 2 years. Renal tubule adenomas were observed in two 5,000 ppm males, and one renal tubule carcinoma was observed in a 1,700 ppm male. During an extended evaluation, renal tubule adenomas were observed in two additional 5,000 ppm males, four 1,700 ppm males, and two 500 ppm males. Renal tubule hyperplasia was observed in exposed groups of males but not in controls, and the incidences in 1,700 ppm males from both standard and extended evaluations were significantly greater than those in the controls. Necrosis and regeneration of the renal tubule epithelium were observed in all control and exposed male rats and in most female rats at 12 months and 2 years. The severity of nephropathy in exposed males and females was significantly greater than that in the controls. In exposed males and 1,700 ppm females at 2 years, the incidences of hyperplasia of the transitional epithelium in the kidney, which commonly accompanies advanced nephropathy, were greater than those of the controls, and the severity of this lesion in exposed males and females was greater than that in the controls. The incidences of renal tubule pigmentation in all exposed groups of males and females at 12 months and 2 years were significantly greater than those in the controls. Squamous cell carcinomas of the tongue were observed in one 500 ppm male at 12 months and one 5,000 ppm female at 2 years, and one squamous cell carcinoma of the oral mucosa was observed in each group of exposed males and in one 5,000 ppm female at 2 years. At 2 years, squamous cell papillomas were observed in the oral cavity (oral mucosa or tongue) of one control, one 500 ppm, two 1,700 ppm, and four 5,000 ppm males; this lesion was also observed in one control and one 500 ppm female. GENETIC TOXICOLOGY: Results of mutagenicity tests with D&amp;C Yellow No. 11 in Salmonella typhimurium were equivocal in one study, based on responses observed in strain TA100 with induced rat liver S9, and weakly positive in a second study, based on responses observed in strains TA98 and TA100 with induced rat or hamster liver S9. D&amp;C Yellow No. 11 induced sister chromatid exchanges and chromosomal aberrations in cultured Chinese hamster ovary cells, with and without S9. No increase in the frequency of micronucleated normochromatic erythrocytes was observed in peripheral blood samples from male and female B6C3F(1) mice administered D&amp;C Yellow No. 11 in feed for 13 weeks. CONCLUSIONS: Under the conditions of this perinatal exposure followed by a 2-year dosed feed study, there was some evidence of carcinogenic activity of D&amp;C Yellow No. 11 in male F344/N rats based on increased incidences of hepatocellular adenoma, renal tubule neoplasms, and squamous cell neoplasms of the oral cavity. There was some evidence of carcinogenic activity in female F344/N rats based on increased inci dences of hepatocellular neoplasms. Incidences of uncommon squamous cell carcinoma of the oral cavity in females may have been related to chemical treatment. Exposure of rats to D&amp;C Yellow No. 11 in feed for 2 years resulted in increased incidences of nonneoplastic liver lesions including clear cell foci, increased basophilia and granularity in the cytoplasm of hepatocytes, and bile duct, hepatocyte, and Kupffer cell pigmentation in males and females and mixed cell foci in males. In the kidney, there were increased incidences of renal tubule pigmentation and transitional epithelial hyperplasia in males and females and renal tubule hyperplasia in males. The severity of nephropathy was increased in exposed males and females. Synonyms: 2-(2-Quinolinyl)-1H-indene-1,3-(2H)-dione; 2-(2-quinolyl)-1,3-indandione Trade names: Arlosol Yellow S, Chinoline Yellow D (soluble in spirits), Chinoline Yellow ZSS, C.I. 47000, C.I. Solvent Yellow 33, Nitro Fast Yellow SL, Oil Yellow SIS, Petrol Yellow C, Quinoline Yellow A Spirit Soluble, Quinoline Yellow Base, Quinoline Yellow Spirit Soluble, Quinoline Yellow SS, Solvent Yellow 33, Waxoline Yellow T