Pesticide Residue

The Environmental Working Group (EWG) has released this year’s list of 48 supermarket fruits and vegetables, ranked according to how much pesticide residue they carry. For the second year in a row, apples were ranked first for having the most pesticide contamination.

"The USDA washes and peels the produce items that it tests and they still find pesticide residues on 65 percent of the samples," Alex Formuzis, vice president for media affairs at the EWG, told CBS News

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Which Fruits and Vegetables Have the Most Pesticide Residue?

They're known as the "Dirty Dozen," and they are, in order:

  • apples
  • strawberries
  • grapes
  • celery
  • peaches
  • spinach
  • sweet Bell Peppers
  • nectarines (imported)
  • cucumbers
  • cherry tomatoes
  • snap peas (imported)
  • potatoes

This year, the EWG found that every sample of imported nectarines and 99 percent of apple samples tested positive for at least one pesticide. The average potato contained more pesticides by weight than any other food. One grape sample contained 15 pesticides, while individual samples of celery, cherry tomatoes, imported snap peas, and strawberries contained 13 different pesticides apiece.

For the third year, the EWG expanded the Dirty Dozen list with an additional category, which included kale, collard greens, and hot peppers. They don’t meet the criteria to be in the Dirty Dozen, but they still contain insecticides that can be toxic to the human nervous system. (As a result, the EWG recommends that people who often eat these foods purchase organic versions.)

Why Do Apples, Strawberries, and Grapes Have the Most Residue?

Sharon Palmer, R.D., a dietitian and nutritionist from California and the author of The Plant-Powered Diet, said that some fruits and vegetables, especially those that are eaten with the outer skin on, tend to carry more residue. 

Are these foods unsafe to eat? No, Palmer said. Consumers can eliminate pesticide residue by effectively washing their produce. Some people argue that the pesticides are there but aren’t harmful to the human body—a notion that other experts completely disagree with.

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Which Fruits and Vegetables Have the Least Residue?

The EWG’s "Clean Fifteen" list for 2014—foods with the lowest amounts of pesticide residue—includes avocados, sweet corn, pineapples, cabbage, frozen sweet peas, onions, asparagus, mangoes, papayas, kiwis, eggplant, grapefruit, cantaloupe, cauliflower, and sweet potatoes.

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How Can Eating Pesticide Residue Harm Human Health?

Palmer explained that pesticides are used to disrupt the life cycle of insects and fungi so that they do not damage food crops.

“Although the Environmental Protection Agency establishes maximum pesticide residue levels to make sure they are below safety standards, safety concerns exist,” she said, adding that the safety thresholds are based on exposure to a single pesticide, though some foods show evidence of exposure to multiple pesticides.

“Even very small doses of some pesticides may have strong effects, especially among children, pregnant women, nursing women, the elderly, and agricultural workers,” Palmer said.

Scientists are calling for more research on the effects of pesticides, which may include brain and nervous system disorders, cancer, reproductive problems, birth defects, metabolic effects, immune system disorders, and more, Palmer added.

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Does Buying Organic Reduce My Risk of Ingesting Pesticide Residue?

It does, according to Palmer.

“Eating organic foods reduces the number of pesticides you are exposed to, because most synthetic pesticides may not be used on these crops,” she added.

Jessica Fishman Levinson, a dietitian and nutrition consultant based in New York, agrees. She says she always tells people that they should purchase organic varieties of produce on the EWG's Dirty Dozen list.

How Can I Get Rid of Pesticide Residue?

Wash your produce—and wash it well. After washing, pat it dry to remove any excess dirt.

"It’s better to eat conventional produce than to skip it altogether,” said Fishman Levinson.

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