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Direct black 38, direct blue 6, direct brown 95, benzidine derived dyes.

Thomas-AW; Boeniger-MF; Weber-MG; Stein-HP; Millar-AC
Am Ind Hyg Assoc J 1978 Aug; 39(8):A-18--A-24
Results of preliminary studies by the National Cancer Institute (NCI) and the National Institute for Occupational Safety and Health (NIOSH) of benzidine (92875) derivative dyes, Direct-Black-38, (1937377) Direct-Blue-6 (2602462), and Direct-Brown-95 (10300740) are summarized and their implications for occupational health are given. Ninety day feeding studies conducted on 120 rats and 120 mice by NCI resulted in cancerous and precancerous liver conditions in the rats and liver cell degeneration in the mice. Liver conditions of the rats were similar to those produced by known carcinogens. Amounts of benzidine found in the urine of animals tested by NCI were greater than the amounts of benzidine in the dyes fed to test animals. NIOSH field studies have shown that humans working with these same dyes excreted higher than expected levels of benzidine in their urine. NIOSH recommends that these substances be handled in the workplace as if they were human carcinogens. NCI investigators believe that a cancer causing potential exists upon exposure to the benzidine derived dyes through the metabolic conversion of the dyes to benzidine in animal bodies. Some of the industries in which employees are exposed to these dyes are paper and allied products, petroleum and related industries, rubber and plastic products, leather and leather products, instrumentation, measuring devices and banking, and kimono painters and dyers. Reference to guidelines for controlling worker exposure to these dyes available in publication form are included.
Aromatic-amines; Carcinogens; Aromatic-hydrocarbons; Dyes; Coloring-materials; Industrial-chemicals; Dye-industry; Short-term-exposure; Animals; Occupational-health; NIOSH-Author
92-87-5; 1937-37-7; 2602-46-2; 10300-74-0
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American Industrial Hygiene Association Journal
Page last reviewed: September 2, 2020
Content source: National Institute for Occupational Safety and Health Education and Information Division