August 20, 2012 |

New Study Prompts Closer Look at Farm Pesticide Safety

SEATTLE - A new look at the effects of a common farm pesticide on children has stepped up calls for the Environmental Protection Agency (EPA) to further restrict, or even ban, its use. The farm insecticide chlorpyrifos is in wide use on Washington farms and feedlots, and it's on the hot seat again, due to a new study from Columbia University that says the chemical appears to affect boys' brain development more than that of girls.

Chlorypyrifos is a chemical sprayed on fruit trees and a wide variety of crops; it is also used on feedlots for insect control. The latest of many safety studies followed the same children from birth to age 7. It found that boys exposed to the chemical had lower memory scores than girls, a key risk for a lower IQ.

That finding doesn't surprise Emily Marquez, Ph.D., a staff scientist for the Pesticide Action Network.

"It causes problems in brain development, so that's why we're concerned about children, in particular, being exposed to chlorpyrifos. Also, it acts at doses that are much lower, and causes these problems with brain development in animal models."

Manufacturer Dow AgroChemical says chlorpyrifos has been "widely used and extensively studied for decades," is registered for use in more than 100 countries and prevents major crop losses by controlling pests.

The EPA phased chlorpyrifos out of indoor and home use beginning in 2000, but concerned watchdog groups have been asking for a full ban since 2007. Earthjustice attorney Kristen Boyles says they're still in court, now challenging the delay.

"I think that the agency shies away from the issue because it is so controversial, and it would just be better for them if they could go forward with the status quo. But the status quo is poisoning people - poisoning children, poisoning farm workers - and that's not right."

Last month, the EPA revised its standards for spray drift. Now, when farmers apply chlorpyrifos, the spray can only contain two pounds of active ingredient per acre, down from six pounds. For all crops except citrus fruits, the standard was already two pounds or less, but Marquez says the move is encouraging.

"That is a good thing, that they're considering bystanders in their policy, as people who are also impacted by pesticide drift. Children are definitely among those in that group."

The EPA says farm workers can limit their exposure with personal protective equipment, including double layers of clothing when mixing or loading sprayers. The agency is set to re-evaluate chlorpyrifos in 2015. Challengers are asking that it be done sooner.

Information about the Columbia University study is available at PANNA information may be found at The Dow AgroChemical website is

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