Evaluation of environmental carcinogens for cancer in man

The problem of the presence of carcinogens in the environment has become of considerable concern to the public, as it has been to the biomedical community for some time. The burden of identifying carcinogenic agents and determining threshold levels, if they exist, falls upon the scientific community. Particular care must be exercised in the design, conduct and analysis of experiments directed toward the identification of carcinogens. The data generated from such tests provides the basis for regulatory decisions by governmental authorities. The advice provided by scientists must be based on sound data. There have been instances, however, and there will be others, in which biological variability and the limits of sensitivity of our tests will give equivocal results. It is the duty of scientists to bring such uncertainties to the attention of the public while working towards the development of more sensitive and precise techniques.