Record Display for the EPA National Library Catalog


Main Title Carcinogenicity of Chlorination By-Products: Trihalomethanes.
Author Pereira, Michael A. ;
CORP Author Health Effects Research Lab., Cincinnati, OH.
Year Published 1981
Report Number EPA-600/D-81-335;
Stock Number PB82-131855
Additional Subjects Chlorination ; Toxicology ; Carcinogens ; Deoxyribonucleic acid ; Chloroform ; Pathology ; Carcinogenesis ; Methane/trihalo
Internet Access
Description Access URL
Library Call Number Additional Info Location Last
NTIS  PB82-131855 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 28p
There is insufficient evidence to indicate anything but the weakest, if any, tumor initiating activity for trihalomethanes. Chloroform in all the tests other than the low level of DNA binding did not indicate any possible tumor initiating activity. The only indication that the other trihalomethanes are tumor initiators was their marginal mutagenic activity in the Ames Salmonella Assay. The trihalomethanes would appear to possess tumor promoting activity as indicated by (1) induction of regenerative hyperplasia, (2) molecular markers such as induction of ODC and (3) the apparent weak promoting activity of chloroform in the rat liver foci bioassay. The dose-response relationship of the tumor promoting activity of chloroform could possess a threshold as indicated by the induction of ODC and regenerative hyperplasia. Therefore, the weight of the present evidence would indicate that the extrapolation model employed to estimate the low dose carcinogenic response for chloroform should be different than the model used for genotoxic carcinogens. However, it must be emphasized that confirming evidence is required to support this conclusion.