Exposure to Pesticides Is Lowered When Young Children Go Organic
By Carol Kaesuk Yoon

A detailed assessment of the study

Preschool children are famously voracious herbivores, putting away huge quantities of fruits, juice and vegetables day after day. In fact, so large are the amounts they eat relative to their small size that many parents — and researchers — have wondered whether feeding children organic versus conventionally farmed produce makes any difference to their health.

A study reported recently by scientists at the University of Washington does not answer the question. But it did find that children fed predominantly organic produce and juice had only one-sixth the level of pesticide byproducts in their urine compared with children who ate conventionally farmed foods.

The study's data showed that an organic diet could, under some circumstances, decrease a child's pesticide exposure — as measured from byproducts in the urine — from above the amounts considered to be of negligible risk by the Environmental Protection Agency to levels below.

But the researchers noted that the level of health risk, if any, posed by such exposure was unknown.

"People want to know, what does this really mean in terms of the safety of my kid?" said Cynthia Curl, a research scientist at the University of Washington and the lead author of the study. "But we don't know. Nobody does." The study was published in Environmental Health Perspectives, a journal of the National Institutes of Health.

The questions remain, in part, because researchers measured organophosphorus pesticide exposure by testing the level of the pesticides' metabolites, or breakdown products, in the children's urine. But there are many organophosphorus pesticides, including malathion and phosmet, that produce these metabolites and they can vary widely in toxicity. So the scientists can make only rough estimates of the relative risk associated with particular levels of pesticide metabolite in the urine.

But the real problem, scientists agree, is the lack of knowledge generally on the health risks — if they exist — of eating foods treated with pesticides. Though many people assume trace elements of pesticides in the diet must be dangerous, others say evidence of danger is sketchy, at best.

"This justifies the importance of an organic diet, that organic foods lower a child's exposure," said Dr. John Wargo, a specialist in risk analysis at Yale. "Industry people are saying show me the dead bodies. I don't want people gambling with my kids that way."

But Dr. David M. Klurfeld, a nutritionist at Wayne State University in Detroit, said: "I'm not saying there is no possible health hazard. But we have to be realistic and that means not to panic over any of this. I would not change any of my or my family's eating habits based on this study."

Researchers recruited subjects by interviewing families as they left a Seattle area food cooperative or retail chain supermarket. Each draws a middle-income to upper-middle-income clientele.

Families with children 2 to 5 years old were selected and asked to keep diaries of foods eaten and to provide urine samples. Children who ate at least 75 percent organic produce and juice were classified as organic. Those eating at least 75 percent conventional produce were classified as conventional.

Because preschoolers are so small and spend much time rolling on lawns and floors, and sucking on thumbs and toys — all of them possibly increasing their contacts with pesticides — researchers have long wondered about the relative importance of different routes of exposure.

But researchers said in the current study that the use of pesticides in the home did not appear to play a significant role in the levels of exposures of these children.

Ms. Curl said the research was begun because an earlier study of the effects of income level on pesticide exposure found one child with absolutely no organophosphorus pesticide byproduct in his urine — a highly unusual situation. It turned out he was fed an entirely organic diet, suggesting that diet might be a particularly important source of exposure for small children.

The earlier study found no relationship between income level and pesticide exposure.

Dr. Richard Fenske, an environmental health scientist at the University of Washington and an author on the new paper, said that the missing piece of the puzzle, the risk from varying levels of pesticide exposure, could ultimately come from proposed federal research known as the National Children's Study.

This study aims to examine the relationship between environmental exposures and health and development by following more than 100,000 children from birth to adulthood.

Most health experts agree that even if it turns out that small amounts of pesticide residues in the diet present a health risk, the advantages of a diet rich in fruits and vegetables will probably far outweigh them. Experts also note that it is impossible to escape exposure to pesticides without avoiding fruits and vegetables entirely, since plants produce them in their leaves or fruit since plants produce them in their leaves or fruit to protect themselves.