[Identification of trihalomethanes in drinking water and assessment of their toxicity, mutagenicity and carcinogenicity]. / Identifikatsiia v pit'evoi vode nekotorykh trigalometanov i vyiavlenie ikh toksichnosti, mutagennosti i kantserogennosti.

ABSTRACT

Dichlorobromomethane (DCMB) and dibromochloromethane (DBCM) isolated from chlorinated drinking water were tested for toxicity, mutagenicity and carcinogenicity. Both agents proved mutagenic in a "dessicator" modification of the Ames test using Salmonella typhimurium TA98 and TA100 in the presence of exogenous metabolic activation. In aquarium Danio rerio fish tests, LD50/30 was 250 mg/l for both compounds. Both agents induced hepatocellular carcinoma in fish DCMB--in 11 out of 29 animals (at 16.5 weeks) and DBCM--in 3 out of 16 (at 26.5 weeks). These data merit further investigation of the agents' carcinogenicity in chronic experiments in rodents.