title: The value and limitations of short-term genotoxicity assays and the inadequacy of current criteria for selecting chemicals for cancer bioassays.
abstract: The Salmonella gene mutation assay is established as the primary in vitro test for genotoxicity. It does not, however, detect all known genotoxic carcinogens, and several mammalian cell genotoxicity assays are now used to complement the Salmonella test--the most usual being cytogenetic analysis in vitro. Use of these two tests provides an adequate screen for genotoxins, but leaves undetected a variety of weak, DNA-unreactive animal carcinogens such as DDT, saccharin and diethylhexyl phthalate. A reappraisal of the present confused situation examines the underlying problems and options for action. It is suggested that the most effective way of focussing resources on the detection of possible new human carcinogens involves in vitro evaluation of genotoxicity, followed where appropriate by further evaluation in vivo, with urgent attention being paid to the methods currently used to select chemicals for cancer bioassays and to the resolution of the current debate on the validity of some recent classifications of carcinogenicity.
mesh_terms: D000818:Animals; D001681:Biological Assay; D002273:Carcinogens / Q000145:classification; D006801:Humans; D066298:In Vitro Techniques; D009152:Mutagenicity Tests
chemical_list: D002273:Carcinogens