CI Direct Black 38

**Semantic type:** Hazardous or Poisonous Substance

**Definition:** A Benzidine-based azo dye that is metabolized to free Benzidine in vivo. Direct black 38 is primarily used for the dyeing of textiles, leather and paper. Benzidine and its metabolic derivatives have been detected in the urine of workers exposed to Benzidine-based dyes. Exposure to this dye is strongly associated with the occurrence of bladder cancer. (NCI05)

**Synonyms:** - 4-Amino-3-[[4'-((2,4-Diaminophenyl)azo)(1,1'-Biphenyl)-4-yl]azo]-5-Hydroxy-6-(Phenylazo)- 2,7-Naphthalenedisulfonic Acid, Disodium Salt - CI 30235 - DIRECT BLACK 38 - Direct Black 38