The contribution of epidemiological and experimental data to the control of environmental carcinogens

Abstract

The implementation of efficient measures for preventing human cancer is directly related to knowledge of what causes the disease. At present, most of the recognized etiological agents for human cancers are man-made or man-refined chemicals, forms of radiation and cultural habits such as tobacco smoking. While epidemiology has contributed greatly to identifying most of these etiological factors, it may have inbuilt limitations that prevent it from detecting small increases in the risk of dying of cancer that may be due to low levels of exposure to carcinogenic factors. Assessment of carcinogenic risk to humans today takes into account results from epidemiological studies, when they are available, and from in vivo toxicity and carcinogenicity tests, metabolic studies and in vitro tests. The role of experimental data in predicting carcinogenicity to humans is still of great importance, although recently there have been attempts to discredit their significance.