[Epidemiological aspects in carcinogenic risk evaluation arising from pollution]

Descriptive epidemiology in which population groups are studied can be of considerable value in drawing attention to a potential carcinogen. This must be followed by analytical studies which might either lead with a fair degree of certainty to the identification of the responsible factor or at least help to identify the high-risk group who could then be screened for the suspected cancer. Such epidemiological research must always take into account the results of experimental studies.