Prediction of non-genotoxic carcinogenesis.

The distinction between genotoxic and non-genotoxic mechanisms of chemical carcinogenesis is now generally accepted. This acceptance implies a revised approach to the definition and measurement of genotoxicity. It is proposed that genotoxicity should be assessed as part of the overall evaluation of the toxicity of chemicals, not as a separate and isolated activity. The level and duration of dosing plays a critical role in the observation of genotoxic phenomena, and such parameters should assume greater importance in the interpretation of genotoxicity data. Toxic events associated empirically with the non-genotoxic aspects of chemical carcinogenicity are discussed.