The precautionary principle: Protecting against failures of scientific method and risk assessment

The precautionary principle has been increasingly incorporated into nationa l and international legislation to protect the environment from anthropogen ic impacts. Suggestions for redefinition of the principle have been made (G ray and Bewers, 1996). Adopting these suggestions would entail using a risk -based approach to environmental protection rather than a truly precautiona ry approach. There remain enormous gaps in our understanding of the identit y and of the individual or combined toxicity of chemicals released to the m arine environment. This is also true of the actual doses involved in enviro nmental exposures, whereas the most appropriate ways of determining ecosyst em impacts have not yet been identified. Classical toxicological assumption s applied to dose-response relationships can no longer be regarded as unive rsally applicable. Ecotoxicology, consequently, contains irresolvable indet erminacies. It is clear, therefore, that the continuing application of the precautionary principle as a paradigm for regulatory action, as a means of recognizing and accounting for limitations to scientific evidence, is an ap proach that is both scientifically defensible and capable of ensuring a hig h level of environmental protection. (C) 1998 Elsevier Science Ltd. All rig hts reserved.