Risk analysis: an overview

Risk analysis increasingly is considered as an integral part of the environmental management decision-making process. Risk, defined as the probability of occurrence of a particular adverse effect on human health or the environment, should not be confounded with hazard, defined as a source of potential injury independent of occurrence. Risk analysis has to be followed by risk management. Some opponents of risk analysis make the reproach that the science used in risk analysis is immature and consequently that the entire process in laden with hidden value judgments. Attempts to overcome these critics are increasingly based on the use of robust biologic data the final considered values system being efficacy-based, efficiency-based or equity-based. Globalization has brought with it new problems, and there is an urgent need to improve risk analysts; to increase its public acceptability and to establish consensus regarding solutions to global environmental problems. In this context biologic-based models and biomarkers hold, the greatest promise for improving risk assessment. These considerations are illustrated by a few examples, also pertaining to low-dose extrapolation and to the problem of thresholds for carcinogenesis. Future directions for development are evoked.