AbstractNew molecular methods have been developed to be used in assessing exposure to and effects of genotoxic and carcinogenic compounds. DNA and protein adducts are measures or surrogates of target dose. Molecular methods are available to probe mutations in oncogenes, antioncogenes, and other specific genes. Furthermore, concentrations of oncoproteins can be determined in biological fluids. If a close link is established between these markers and risk of cancer, they can be used as independent endpoints in the prevention of cancer.