Acute poisonings of farm workers and children were the most obvious risks, but mounting scientific evidence gradually revealed a panoply of subtler hazards. Persistent pesticides accumulated in wildlife food chains, decimating populations of eagles, pelicans and other predators. Toxicological experiments showed that pesticides can cause cancer and birth defects, and damage or interfere with the nervous, endocrine, reproductive and immune systems in mammals. Decades of research have only begun to unravel the many ways these chemicals affect human health. Yet, while the effects remain too little understood, we all are exposed to several pesticides in our food each day, and millions of Americans drink water tainted with pesticides.
Pesticide use around the home, lawn and garden delivers occasionally larger doses.
Science cannot say precisely how large the risks from these exposures are, for an individual. But a long-standing consensus holds that the collective risks to public health are substantial. Health concerns aside, the promised conquest of nature by chemical pesticides has proved to be a tarnished miracle, at best. As pesticide use has expanded, so has the public cost of our reliance on chemical pest control. Beyond the largely unquantifiable costs of health risks, over a billion dollars is spent each year for the regulatory, surveillance, monitoring and enforcement programs we need to try to use pesticides safely.