Reconciling scientists' beliefs about radiation risks and social norms: explaining preferred radiation protection standards.

Social scientists have argued about the role of political beliefs in highly charged policy debates among scientific experts. In debates about environmental hazards, the focus of contention is likely to rest on the appropriate scientific assumptions to inform safety standards. When scientific communities are polarized, one would expect to find systematic differences among combatants in the choice of appropriate assumptions, and variation in the application of "precaution" in standard setting. We test this proposition using an experiment applied in a mail survey format to groups of scientists from opposing sides of the nuclear policy debate. Questions were asked about the role of political, social, and epistemological beliefs in reaching scientific and policy judgments about the relationship between radiation dose and cancer incidence in human populations. We find that the precautionary tendency is pervasive regardless of whether the scientist is associated with a putatively pro- or anti-nuclear group. Using a multinomial logit model, we explain a modest percentage of the variation in the choice of preferred judgments about safety standards, but find that distinct sets of political and social values are significantly associated with policy positions among scientists. Implications for scientific advice to policymakers are discussed.