One of the sources of evidence for the somatic mutation hypothesis of cancer is in studies of cor relation between mutagenic and carcinogenic ca pacities of physical and chemical agents. Tests in this laboratory have suggested a positive correla tion within the limits of three mustard compounds. Both the nitrogen mustard, methylbis (2-chloroethyl)amine hydrochloride, and sulfur mustard, bis(2-c...

So far as we know, a spontaneous growth of chorionic tumor has not been reported in any kind of animals. Recently, Shintani et al.1 first described an experimental chorionic tumor produced by carcinogenic agents in rats. For the last three years we have dealt with experimental production of chorionic tumor, and very recently have succeeded in producing a chorionic tumor by means of destruction ...

Readily achieved comparative assessment of carcinogenic risks consequent upon environmental exposures may increase understanding and contribute to cancer prevention. Procedures for hazard identification and quantitative risk assessment are established, but limited when addressing novel exposures to previously known carcinogens or any exposure to agents having only suspected carcinogenic activit...

Use of laboratory animals to identify carcinogenic potential of chemicals, mixtures, and other agents has a modern history of greater than 40 years from which much useful scientific and public health information can be derived. While laboratory animals differ from humans in some respects that may affect responses to hazardous exposures, use of such models is based on experimental evidence indic...