A compass for health: rethinking precaution and its role in science and public health.

precautionary principle continues to be a highly controversial topic in health and environmental policy. Despite its prominent role in key environmental treaties and European Union policy, 1 consensus on its scientific foundations and practical implications remains elusive. In our view, three common criticisms of the precautionary principle arise from misunderstandings of how precautionary policy relates to science; and in this viewpoint we address these criticisms. The precautionary principle has been criticized for: stifling innovation, 2 causing unintended consequences potentially more serious than the problem that triggered the precautionary action in the first place, 3 and creating 'false positives'—apparent risks that waste resources and distract from real problems. 4,5 Background The precautionary principle encourages policies that protect human health and the environment in the face of uncertain risks. In this broad sense, it is not a new concept. Precaution is at the heart of medical and public health practice, as embodied in the 'first do no harm' tenet of medicine. The term 'precautionary principle' can be traced to the German word Vorsorgeprinzip. 6 An alternative translation of this word might be the foresight or 'forecaring' principle—emphasizing anticipatory, forward-looking action rather than reactive impeding of progress. A widely cited definition of the precautionary principle is the Wingspread Statement, which states: 'when an activity raises threats of harm to human health or the environment, precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically.' 7 The 2001 Lowell Statement on Science and the Precautionary Principle, 8,9 signed by an international group of scientists, legal scholars, medical professionals and others, elaborated on elements of the principle, including: • Upholding the basic right of each individual (and future generations) to a healthy, life-sustaining environment; • Action on early warnings, when there is credible evidence that harm is occurring or likely to occur, even if the exact nature and magnitude of the harm are not fully understood; • Identification, evaluation, and implementation of the safest feasible approaches to meeting social needs; • Placing responsibility on originators of potentially dangerous activities to thoroughly study and minimize risks, and to evaluate and choose the safest alternatives to meet a particular need, with independent review; and • Application of transparent and inclusive decision-making processes that increase the participation of all stakeholders and communities, particularly those potentially affected by a policy choice. In this context, precaution becomes a compass to guide decisions under …