Validity of Short-Term Tests to Detect Carcinogenic Chemicals

Recent advances in understanding of genetic and molecular mechanisms of chemical toxicity have made possible short-term in vivo and in vitro tests to help evaluate the effect of the numerous chemicals in the human environment. The use of these tests has been extensively discussed (Hollstein et al. 1979). Discussion has focused on the significance of the biological end-points and the capacity for metabolic activation. Further aspects of in vitro test systems have received less attention, although they might strongly influence the outcome of the test and its interpretation. One is the balance between the metabolic activation and inactivation of the test compounds; another is the presence in the “artificial” growth media of various components which might alter the cellular response to the toxic agents. Furthermore, the specificity of methods for monitoring toxic effects, especially DNA damage, have not been sufficiently examined.