Buying Organic to Avoid Pesticides? Science Confirms You Have the Right Idea

Researchers are trying to understand how all the chemicals in our food might be harming us in the long run.

(Photo: Martine Doucet/Getty Images)

Feb 5, 2015· 2 MIN READ
Jason Best is a regular contributor to TakePart who has worked for Gourmet and the Natural Resources Defense Council.

Eat organic produce, and you end up exposed to less pesticide.

That would seem like a no-brainer: Certified organic produce, after all, is by definition grown without the use of pesticides. Nevertheless, new research published Thursday came to that common-sense conclusion through scientific rigor, adding to the growing body of evidence that should make you feel better about shelling out more for organic apples. Perhaps more important, it contributes to the larger effort by scientists to come up with ways to evaluate people’s long-term exposure to certain pesticides and better understand what that exposure may be doing to our health. The researchers also found some concerning evidence that, contrary to both popular belief and federal regulatory standards, organic produce might not be altogether free of pesticides.

For the study, which appears in the journal Environmental Health Perspectives, a team of researchers led by scientists at the University of Washington reviewed data collected from more than 4,400 participants as part of another long-term health study—you know, one of those where a bunch of information is collected from a range of people who are then followed for a certain period of time.

In this case, all the participants were over 45, but they were from racially diverse backgrounds. The researchers first analyzed the participants’ responses to a dietary questionnaire, focusing specifically on answers related to how much fruit and vegetables they consumed and how often that produce was organic. Then they tested participants’ urine for exposure to organophosphate pesticides, one of the most widely used classes of pesticides in U.S. agriculture.

Not surprisingly, when the researchers compared people who reported eating organic produce most often with those who said they almost never did, they found significantly lower amounts of lingering pesticides among the prior group. Interestingly enough, this only held true when the amount of produce consumed was roughly equivalent. In other words, people who ate less produce overall, even if it wasn’t organic, showed less exposure to pesticide compared with people who reported eating more organic produce.

“On its face, this finding is counterintuitive and perhaps even concerning, as it might suggest that organic produce is not actually free of [organophosphate] pesticides,” the authors write. “However, we hypothesize that this reflects the difference in total produce consumption among these groups. This study did not include a group of individuals who exclusively ate organic produce, and it is difficult to know exactly how much of a participant’s diet is organic when they report that organic produce is ‘often’ eaten.”

Thus, while vegetable haters may be inclined to one takeaway here (Don’t want to be exposed to pesticides? Don’t eat produce), the healthier line appears to be that if you’re worried about long-term pesticide exposure, buying organic is the way to go.

How worried should you be about the organophosphates that might be lurking in your crisper? Honestly, no one knows for sure.

The Environmental Protection Agency was concerned enough about acute exposure to organophosphates to ban their household use back in 2000. But this class of pesticides, derived from nerve gas produced as a chemical weapon during World War II, continues to be sprayed extensively on crops. It’s yet another blind spot in our federal regulatory system that the danger such chemicals poses to human health has generally been determined based on adult exposure to significant quantities over a relatively short period of time. The EPA’s view that long-term, low-level exposure is “safe” is based more on faith than on science.

It’s exceptionally difficult from a scientific standpoint to calculate the risks of such exposure, and as it turns out, that’s the primary aim of the current study—not to give you a warm glow when you opt for organic salad greens. Public health researchers are looking for a scientifically valid way to evaluate a person’s long-term exposure level, which may then be used in other research trying to determine the health risks that might be associated with such exposure.

In the meantime, organophosphates have been linked to certain cancers and have been shown to disrupt the endocrine system, according to the Pesticide Action Network. The chemicals have also been linked to neurodevelopment issues in children, including autism. In a paper published in 2012 by the National Institutes of Health, David Bellinger, a professor of neurology at Harvard Medical School, made the rather jaw-dropping (and media-savvy) calculation that America’s collective IQ has dropped by almost 17 million points owing to exposure to organophosphates. The decline is part of what he and other crusading public health advocates call a “silent pandemic” of toxins that are wreaking havoc on the neurological development of unborn children.

While others have charged Bellinger, et al., with scaremongering, the fact remains: If long-term, low-level exposure to such pesticides has yet to be definitively proved to cause harm, neither has it exactly been proved to be safe.