If the apple you had for lunch seems almost too perfect, you can thank the chemical industry. Conventional farmers use pesticides liberally in their orchards, in part to prevent blemishes that can hurt the value of their product. As a result, Americans have come to assume that apples should be as taut and unblemished as a supermodel’s face—a plastic perfection you wouldn’t often see in unimproved nature.
But perfection isn’t free. According to a new survey by the green activists at the Environmental Working Group (EWG), apples are the most contaminated produce on average, with pesticides showing up on 98% of the more than 700 apple samples tested. (EWG took its rankings from a recent Department of Agriculture survey and other government data.) That put apples on top of EWG’s “Dirty Dozen” list of the most contaminated produce, followed by grapes, strawberries, cilantro, potatoes and oranges, all of which had more than 90% of samples testing positive for pesticide residue. EWG also compiled a “Clean 15″ list of the least-contaminated conventional produce—take a bow, onions—and the entire list can be downloaded in PDF here.
EWG has raised concerns about the health impacts of pesticide residue in the food supply for some time, and the list is meant to help give consumers a little supermarket guidance, according to EWG president Ken Cook:
Though buying organic is always the best choice, we know that sometimes people do not have access to that produce or cannot afford it. Our guide helps consumers concerned about pesticides to make better choices among conventional produce, and lets them know which fruits and vegetables they may want to buy organic.
Pesticides can be very toxic to human beings—unsurprising, since the chemicals are meant to wipe out living things. But it’s not clear how vulnerable consumers eating an apple or grape with a little pesticide residue might be, compared to agricultural workers who are likely being dosed with much greater concentrations of the chemical. There have been studies showing a possible link between maternal exposure in pregnancy to pesticides and a lowered child IQ, and other work showing possible connections between pesticide exposure and attention-deficit hyperactivity disorder. There’s also suspicion that excessive exposure to pesticides can increase the risk of some cancers. Said EDF senior analyst Sonya Lunder in a statement:
Pesticides are toxic. They are designed to kill things and most are not good for you. The question is, how bad are they?
Indeed. But it’s important to keep in mind that the USDA found that just 3% of all the samples of produce, beef and rice it analyzed in this survey had either unapproved chemicals or improper levels of pesticide—at least by the government’s standards. Five unapproved pesticides were found on apple samples, compared to 33 unapproved pesticides on 44% of the cilantro samples. But does that mean the chemicals really pose a danger to consumers’ health? The Alliance for Food and Farming, an industry group, called EWG’s list misleading:
When residues are present on food, consumers can see for themselves how low they actually are by using a new calculator tool now available on the safefruitsandveggies.com website. The calculator is based on a scientific analysis which shows that even a small child could eat hundreds or even thousands of servings of a fruit or vegetable without any impact at all from pesticide residues. “This would certainly seem to fit any definition of ‘low pesticide residue’ foods,” [executive director of the Alliance for Food and Farming Marilyn] Dolan says.
And so we’re back in the magical world of risk perception, where science can become the tool of bias—conscious or not. Whatever the uncertain dangers of pesticides, we can’t forget that we know how important a diet of plentiful fruits and vegetables is for overall health—the USDA just recommended that half our plate be occupied by fruits and veggies—and it would be a shame if fears over pesticides caused some consumers to shun apples or grapes. (Surveys indicate that American kids aren’t getting anywhere near enough.) Green groups like EWG recommend that you go organic when you can, but that produce does cost more—and as my colleague Jeffrey Kluger wrote last year, it’s not certain you’re always getting your money’s worth:
A 2009 study in the American Journal of Clinical Nutrition led to a firestorm in the food world. It found no difference between organic and conventional produce with regard to all but three of the vitamins and other food components studied, and conventional produce actually squeaked past organic for one of those three.
“We draw these bright lines between organic and conventional food,” says [James] McWilliams, [professor of environmental history at Texas State University.] “But science doesn’t draw those lines. They crisscross, and you have people on both sides of the argument cherry-picking their data.”
We all be trying to reduce exposure to pesticides and other chemicals in our food supply—producers, consumers and the government. But the number one priority should be to ensure that Americans eat their fruits and veggies—wherever they come from.
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