This information profile on carbon-black (7440440) lists its chemical structure, Chemical Abstracts Service number, Registry of Toxic Effects of Chemical Substances number, production figures and economic trends in production, uses, number of companies producing and using carbon-black, and the biological effects of exposure. Little information is available on organ damage caused by carbon- black. Bronchopneumonia and emphysema were noted in chronic inhalation studies in mice and monkeys. The acute median lethal dose administered intravenously to mice is 440 milligrams per kilogram. Carcinogenicity studies are reported. No studies of either mutagenicity or teratogenicity of carbon-black have been reported. An epidemiological study of workers in the carbon-black industry found no evidence for increased cancer mortality or morbidity associated with occupational exposure. Inhalation of carbon dust particles at 50 milligrams per milliliter causes slight irritation of the throat and increased mucociliary transport. The threshold limit value for carbon black has been set at 3.5 milligrams per cubic meter.