SAN FRANCISCO - Many U.S. residents carry unhealthy levels of pesticides in their bodies, with children, women and Mexican Americans disproportionately exposed to the toxic chemicals, according to a study to be released Tuesday.

The Pesticide Action Network analyzed data collected by the U.S. Centers for Disease Control and Prevention (news - web sites) in a study of more than 2,648 people tested for levels of 34 pesticides, the environmental group said.

The PAN study — called "Chemical Trespass: Pesticides in Our Bodies and Corporate Accountability" — found that a large percentage of people who had their blood and urine tested carried pesticides above levels considered safe by government health and environmental agencies.

"The pesticide body burden data represents a failure of our approach to how we protect people from toxic pesticides," said Kristin Schafer, the study's lead author and PAN's program coordinator. "We really hope that it will help us move toward a different system of how we control pests in agriculture and all other areas."

San Francisco-based PAN, which advocates for alternatives to pesticide use for pest control, found that the average person in the study carried 13 of the 23 pesticides they evaluated. Many of the pesticides have been linked to infertility, birth defects, cancer and other serious health ailments, said Margaret Reeves, a senior scientist at PAN.

"A growing body of research suggests that even at very low levels, the combination of these chemicals can be harmful to our health," Reeves said.

The PAN study found that children between 6 and 11 years old were exposed to the nerve-damaging pesticide chlorpyrifos at four times the level deemed acceptable by the U.S. Environmental Protection Agency (news - web sites). Chlorpyrifos is designed to kill insects by disrupting the nervous system.

"It does appear to have some validity," said Francis B. Suhre, of the EPA. "The crux of the matter is what does it all mean and is it reflecting past effects as opposed to current. At first blush, it requires further screening."

The study said one company — Dow Chemical Corp. — was responsible for 80 percent of the chlorpyrifos in Americans' bodies. The figure was derived from the amount of the chemical in the bodies of the people tested and a "conservative estimate of Dow's market share," said Skip Spitzer, a program coordinator for PAN and one of the study's authors.

Dow spokesman Garry Hamlin confirmed the company is the largest manufacturer of the pesticide in the country, but said the pesticide leaves the body quickly without doing harm. He said the CDC has noted that the measurement of an environmental chemical in a person's blood or urine does not mean that the chemical causes disease.

"Chlorpyrifos is widely used, and studies by the Centers for Disease Control suggest that people are exposed to chlorpyrifos at very tiny levels. ... When people are exposed, the product breaks down readily and is eliminated from the body in a matter of days," he said.

The report said that women carry "significantly" higher levels of three pesticides called organochlorines known to reduce birth weight and disrupt brain development in infants.

PAN's analysis also found that Mexican Americans carried higher levels of chemicals linked to the insecticides lindane, DDT and methyl parthion than other ethnic groups.

The PAN study didn't reveal why certain groups were more exposed to certain chemicals because the CDC data didn't include information about where the test subjects lived or what kinds of jobs they held. People are thought to ingest pesticides through air, water and food.

CDC spokeswoman Stephanie Creel said the center would not comment on the findings because it did not participate in the analysis.

PAN researchers believe pesticide makers should be held responsible for the "pesticide body burden" and its financial and health impacts.

"There's a case to be made that the primary responsibility for these pesticides in our bodies lies with the folks that manufacture and market them," Schafer said.

The study recommends that Congress investigate corporate responsibility for pesticide contamination, an EPA ban on using hazardous pesticides, and requiring manufacturers to demonstrate that a pesticide doesn't harm human health before using it.

http://story.news.yahoo.com/news?tmpl=story&u=/ap/20040511/ap_on_sc/pesticide_study ___

On the Net:

Pesticide Action Network: http://www.panna.org

CropLife America: http://www.croplifeamerica.org