Controversies over pesticides: the lessons for public health.

Pesticides and their effects on the environment and human health have been subjects of many debates in recent years. Many factors have contributed to this, including developments in analytical techniques as well as the toxicology of the pesticides themselves. In many cases the discussions have not been purely scientific or confined to the scientific literature. Misunderstanding of statistical concepts-the basic principles of toxicology-have contributed to this situation. The most important adverse effects on humans have been acute accidental poisoning. There remains much room for improvement in this area. Public health authorities can learn from the history of the debate the importance of critical evaluation of data, the need for balanced interpretation of this for the public, the need to limit the use of general health warnings, and the realization that restrictions designed or suggested to limit one problem may give rise to other unforeseen problems of greater immediate health importance.