The Precautionary Principle and Public Health

the nation's largest school district , announced a new policy on use of pesticides in its school buildings. The district committed to a policy of integrated pest management, giving priority to nonchemical approaches to pest control, and set a long-term goal of eliminating all chemical controls. In establishing this policy, the school district invoked the precautionary principle, saying: The Precautionary Principle is the long-term objective of the District. The principle recognizes that: 1. No pesticide product is free from risk or threat to human health, and 2. Industrial producers should be required to prove that their pesticide products demonstrate an absence of [human health risks] rather than requiring that the government or the public prove that human health is being harmed. 1 By stating a set of basic tenets (all pesticides are potentially harmful, and nonchemical methods shall be preferred) and a long-term objective (" to provide for the safest and lowest risk approach to control pest problems while protecting people, the environment, and property "), the policy stimulates the search for safer alternatives without tying the hands of the district when no alternative to a pesticide can be found. The policy is also significant for what it does not include: there is no list of banned substances , nor a stipulation of an " acceptable " level of risk. Whether or not one agrees with this approach to pesticide management (we do), it seems clear that the school district's in-vocation of the precautionary principle raises important issues for public health scientists and activists. In this commentary, we briefly describe the key elements of the precautionary principle, emphasizing several aspects important to public health. Our perspective is informed by a university– community collaborative effort to refine the meaning of the precautionary principle and develop strategies for applying it to environmental health policy. 2,3 We argue that the precautionary principle is good for public health because it promotes the search for safer technologies, encourages greater democracy and openness in public health policy, and stimulates reevaluation of the methods of public health science. The definition of the precautionary principle developed for the Rio Declaration of 1992 is often cited, 4 and the 1998 Wing-spread Statement contains similar language: " 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. " 5 The …