Environmental enemies: environmental factors may be causing many chronic diseases. Tracking the link between them helps.

• Author: Farquhar, Doug

As the largest producer of agricultural products in this country, California applies enormous amounts of pesticides to its farmland. But pesticides can cause acute poisoning, cancer, birth defects and damage to the nervous system if they come in contact with people.

The state wants to know how often that's happening. Before 2001, health officials could track acute pesticide illness in workers, but actual data on the amount of pesticides causing harm in humans was not known. Now, with the passage of the 2001 California Environmental Health Surveillance System Act and the 2003 Health Tracking Act, the state's Environmental Protection Agency and Department of Health Services are reviewing exposure and tracking data to determine levels of toxic chemicals in people. Californians now have reliable information on pesticide use and the potential exposure from it. Beyond knowing how much is being applied to agriculture, the state knows how much of a pesticide is actually being ingested by people, and if it's causing them any harm.

"These laws help California find ways to reduce the growing burden of chronic diseases such as asthma, developmental disorders, some forms of cancer and Parkinson's disease," says Dr. Amy D. Kyle, of the School of Public Health at the University of California Berkeley.

Such information helps both public health and agricultural interests. Although the agricultural community has been resistant to laws that monitor pesticides and their impact on environmental health, Washington Representative Zach Hudgins says the information can actually help farmers who need to be aware of their own exposure to the chemicals. "Educating the farming community by explaining the harm pesticides can cause is beneficial," he says. Farmers may fear that providing data on pesticide use will scare consumers, but they need to know for their own health.

Chronic diseases--such as heart disease, cancer and diabetes--are the leading causes of death and disability in the United States, accounting for seven of every 10 deaths and affecting the quality of life of 90 million Americans. Birth defects, developmental diseases, asthma and neurological disorders can also be caused by the environment. Science is finding new links between the environment and chronic diseases every week.

"Rates of diseases related to the environment are increasing. We need to look at these links more closely to better determine health risks," says Kyle.

State and local health...