Study: Organic diet reduces exposure to neurotoxic pesticides | Pesticide Action Network
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Study: Organic diet reduces exposure to neurotoxic pesticides

Contact: Paul Towers, PAN or 916-216-1082

For Immediate Release: February 5, 2015

Study: Organic diet reduces exposure to neurotoxic pesticides

A new first-of-its-kind study released today examined the long-term exposure of neurotoxic pesticides, including chlorpyrifos, that are applied to crops and found on food across the country. The findings underscore that participants who consumed organic food were less likely to find traces of the pesticides in their bodies.  

Organophosphate (OP) insecticides are widely used in U.S. agriculture, and exposure through residues of these pesticides on commonly eaten fruits and vegetables could be an important pathway of exposure for consumers. Over one million pounds of chlorpyrifos, an OP, are applied each year in California alone and are one of the most widely used pesticides near schools in agricultural regions.

The study looked at 14 organophosphate insecticides in nearly 4,500 study participants from six U.S. cities. It compared them to measurements of breakdown products, or metabolites, of OP pesticides found in participants’ urine. The organophosphate pesticide chlorpyrifos is increasingly linked to falling IQs, ADHD and autism spectrum disorder in children.

The researchers found that consuming organic fruits and vegetables significantly reduced the detection of OP metabolites in the study participants’ urine.  Those who "often or always" ate organic fruits and vegetables averaged approximately 65% lower levels of OP metabolites in their urine than those who "rarely or never" ate organic. This indicates that consuming a largely organic diet could be very beneficial in reducing exposure to OP pesticides for all consumers.

While the levels of OP breakdown products found were below what is currently categorized as risky by the EPA, the researchers pointed out that these thresholds of risk “may not reflect important mechanisms of low-level toxicity, which are only beginning to be understood.” After years of litigation by PAN, farmworker and environmental health and justice organizations, both US EPA and the California Department of Pesticide Regulation are considering additional health protections, upon completions of new risk assessments.

Emily Marquez, PhD, staff scientist for Pesticide Action Network released the following statement:

“This first, and largest of its kind, study suggests that eating organic food is a way to reduce dietary pesticide exposures.  According to the study, the primary route of exposure to neurotoxic pesticides like chlorpyrifos is through diet, with 75% of the US population found to have OP pesticides in their bodies.

The study also reminds us that an increasing body of scientific evidence suggests that children are vulnerable to the impacts of pesticides, even in very small amounts. Existing research continues to link maternal exposure to chlorpryifos that results in changes to children’s brain architecture. Studies also link exposures to ADHD, autism spectrum disorder and diminished IQs in children.

Given the widespread use of neurotoxic insecticides across the country, including in close proximity to schools, the study should be reason for greater government oversight and action.

The study’s approach will serve public health researchers in the future and is an important contribution to the field, with its estimation of dietary exposures in comparison with actual biomonitoring data. The study also lays the groundwork for further understanding the health implications of food residues of chlorpyrifos and other neurotoxic organophosphate pesticides.”