Environmental carcinogenesis

It generally is accepted that approximately 80% of all cancers have an environmental component. However, although the cause and nature of certain human cancers are known, definitive preventative guidelines cannot be offered for many tumors attributed to life style, especially those of the digestive and genitourinary system. This has led to considerable public confusion and political controversy regarding cancer control strategies. Proponents of two divergent strategies for control have emerged: those who emphasize increased regulatory programs designed to control or eliminate minute quantities of pollutants in the ambient environment based on fairly rigid quantitative risk assessment; and those who believe in more intensive long-term research on the molecular biologic mechanisms with the objective of actively intervening in carcinogenic mechanisms. Current data indicate that the eliminatory approach, apart from more effort on certain already recognized exogenous agents, will have little additional impact on the cancer burden. The mechanistic approach, although complex and slow, represents the most logical alternative. Thus, there are increasing efforts directed to evaluating the application of more recent advances in molecular biology to human studies. However, such research strategies require a long-term investment, and no time frame can be offered. Informed scientists have an important role in ensuring that the public is made aware of current scientific views on carcinogenesis and priorities in preventative research.