Bacterial mutagenicity studies on chloroform In vitro

Mutagenicity of carbon tetrachloride and chloroform in Salmonella typhimurium TA98, TA100, TA1535, and TA1537, and Escherichia coli WP2uvrA/pKM101 and WP2/pKM101, using a gas exposure method

“…Although several studies have assayed the mutagenicity of carbon tetrachloride and chloroform in the excision-repair deficient tester strains TA1535, TA1537, TA1538, TA98, and TA100 using gas exposure, none detected positive responses [Simmon et al, 1977;Barber et al, 1981;Van Abbe et al, 1982]. The present study is the first to test the mutagenicity of these compounds in the excision-repair proficient tester strain WP2/pKM101 with gas exposure.…”

“…Several reports indicate that carbon tetrachloride is not mutagenic in S. typhimurium tester strains using either the pourplate or preincubation method Uehleke et al, 1977;Zeiger et al, 1988]; chloroform also is negative in S. typhimurium and E. coli tester strains using these testing protocols [Simmon et al, 1977;Uehleke et al, 1977;Gocke et al, 1981;Kirkland et al, 1981;Van Abbe et al, 1982]. We previously performed a literature review which indicated that some poorly water-soluble, volatile compounds such as 1-bromopropane (boiling point, 71°C) and 1-bromobutane (boiling point 102°C) give negative bacterial mutagenicity responses when using the pour-plate or preincubation methods, but have produced positive response when a gas exposure method is employed [Araki et.…”

“…However, carbon tetrachloride was reported negative in TA1535, TA1537, TA1538, TA98, and TA100 [Simmon et al, 1977] and in TA1535, TA98, and TA100 [Barber et al, 1981] using gas exposure. Likewise, negative bacterial mutagenicity results have been reported for chloroform in assays using gas exposure [Simmon et al, 1977;Van Abbe et al, 1982]. In these studies, the gas exposure conditions were not described in detail, and it is possible that the negative responses might be a consequence of inadequate exposure levels.…”

Carcinogenicity of by-products of disinfection in mouse and rat liver.

“…Chloroform administered in corn oil has been shown to induce hepatocellular carcinomas in mice and epithelial tumors in the kidney of male rats (35). The inability of chloroform to bind significantly to liver and kidney DNA (44)(45)(46) and its lack or very low level of genotoxicity (31,(36)(37)(38)(39)(40)(41)(42)(43) has led to the proposal that the carcinogenicity of chloroform results from a nongenotoxic mechanism such as tumor promotion (45,46). Because the mechanism of carcinogenicity (i.e., genotoxic or nongenotoxic) of a substance has major implications in interspecies and low-dose extrapolation, we attempted to demonstrate the nongenotoxic and tumor-promoting mechanism for the carcinogenic activity of chloroform.…”

“…The administration of chloroform in corn oil by gavage induced liver tumors in B6C3F1 mice (35). Chloroform has been shown to lack or at most possess minimum genotoxic activity (31,(36)(37)(38)(39)(40)(41)(42) and has also been shown to not bind significantly to liver or kidney DNA in rats (43)(44)(45). These findings have led to the proposal that the hepatocarcinogenicity of chloroform in mice results from a nongenotoxic mechanism such as tumor promotion (45,46).…”