Late Lessons From Early Warnings

ISEE-263 Abstract: The PP is “a general rule of public policymaking that can be used in situations of potentially serious or irreversible threats to health or the environment where there is a need to act to reduce potential harm before there is strong proof of harm, taking into account the likely costs and benefits of action and inaction.” Whilst its’ basic rationale has long been used in public health it is only in the last 20 years that the precautionary principle has become an explicit and legal principle of environmental and public health policymaking in Europe. Its potential for misuse is limited by the proportionality principle, which requires the likely costs of avoiding harm not to grossly outweigh the likely benefits. Some of the “Late lessons from Early Warnings” from a number of case studies will be summarised, with particular reference to the use of differential “levels of proof”; to the limitations of some common “criteria” for evaluating epidemiological and other evidence; and to the nature and directions of error in the health and environmental sciences, which, in general, tend towards producing “false negative” results. Some implications for reporting epidemiological results will be presented.