IDENTIFICATION AND USE: Acid Black 52 (AB52) is a black powder. It is a dye for nylon, leather, anodized aluminum & aminoplasts, coloring & printing wool & silk. ANIMAL STUDIES: The effects of acid black 52 (AB52) were studied in rats and hamsters. AB52 was administered intratracheally to hamsters and rats once/wk for 15 wk at concn of 0.56 to 3.16 mg/0.2 mL of saline solution. AB52 was administered orally for 27 mo at 2% level in the diet. Animals were observed for clinical symptoms throughout the study. At the end of the experiments, all animals were killed, and complete necropsies and histopathological studies were conducted. AB52 was not oncogenic in either species by either route of administration. Following intratracheal administration, AB52 produced a dose-related toxic effect in the respiratory tract of both hamsters and rats. At similar dose levels administered intratracheally once a week for 12 consecutive weeks, hamsters and rats showed striking species differences in toxic response. The black dye was more toxic in rats than hamsters at the higher dose level (0.61 mg rat and 0.75 mg hamster); eight male and two female rats died as compared to only two male hamsters. A dose-related mortality rate was apparent among the male groups of each species; however, no such pattern of mortality was observed in females administered the dye. Reduced body weight gain was noted in all male and female groups of both species as compared to their controls (except the male group at the 0.16 mg dose level). Both hamsters and rats exhibited suffocation, extreme breathing difficulty, and collapse immediately following each instillation of the AB52 suspension into the trachea.
WEIGHT OF EVIDENCE CHARACTERIZATION: Applying the criteria for evaluating the overall weight of evidence for carcinogenicity to humans outlined in EPA's guidelines for risk assessment (1986), trivalent chromium is most appropriately designated a Group D -- Not classified as to its human carcinogenicity. Using the Proposed Guidelines for Carcinogen Risk Assessment (1996), there are inadequate data to determine the potential carcinogenicity of trivalent chromium ... However, the classification of hexavalent chromium as a known human carcinogen raises a concern for the carcinogenic potential of trivalent chromium. HUMAN CARCINOGENICITY DATA: Occupational exposure to trivalent chromium and other chromium compounds by inhalation has been studied in the chromate manufacturing and ferrochromium industries; however, exposures all include mixed exposures to both Cr(III) and Cr(VI). Cr(VI) species is the likely etiological agent in reports of excess cancer risk in chromium workers. Data addressing exposures to Cr(III) alone are not available and data are inadequate for an evaluation of human carcinogenic potential. ... ANIMAL CARCINOGENICITY DATA: The data from oral and inhalation exposures of animals to trivalent chromium do not support documentation of the carcinogenicity of trivalent chromium. IARC concluded that animal data are inadequate for the evaluation of the carcinogenicity of Cr(III) compounds. Furthermore, although there is sufficient evidence of respiratory carcinogenicity associated with exposure to chromium, the relative contribution of Cr(III), Cr(VI), metallic chromium, or soluble versus insoluble chromium to carcinogenicity cannot be elucidated... /Chromium (III), insoluble salts/
Evaluation: There is inadequate evidence in humans for the carcinogenicity of metallic chromium and of chromium(III) compounds. There is inadequate evidence in experimental animals for the carcinogenicity of metallic chromium, barium chromate and chromium(III) compounds. Overall evaluation: Metallic chromium and chromium(III) compounds are not classifiable as to their carcinogenicity to humans (Group 3). /Metallic chromium and chromium(III) compounds/
Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR if necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Poisons A and B/
