ABSTRACT
Most toxicologists would agree that the risk assessment of carcinogens and, in particular, the facet that deals with the extrapolation of animal findings to humans is fraught with great uncertainty. While modulation and promotion represent interesting laboratory observations in experimental chemical carcinogenesis, at the present state of the knowledge it is difficult to define any generally acceptable approach to the regulation of these substances. Traditionally, regulatory agencies have placed great emphasis and reliance on the carcinogen bioassay as means of assessing potential human cancer risks from chemicals. Approaching the regulation of carcinogens within a conceptual framework makes it possible to exercise scientific judgement regarding the magnitude of risk. Public perception of risk may differ significantly between nations and cultures depending upon political, social and religious beliefs and the economic forces that set the tone of domestic and international commerce.
