I received the following question from a reader.

Q. My mom called me this morning and told me that she heard on the news that ADHD was caused by vegetables. Then I heard that a new study found that the pesticides left on fruits and vegetables may be the cause of some ADHD. That must have been what she was talking about. My question is, if I boil my vegetables, will that remove the pesticides?

A. In researching this, I found a few pieces of information about boiling vegetables or fruit to remove pesticides, but the information was contradictory. In fact, the information on removing pesticides from fruits and vegetables by any method is contradictory.

The United States Department of Agriculture website is unfortunately silent about removing pesticide residues from food. I did find advice on washing vegetables on the site, but that advice didn’t mention pesticides. It only mentioned washing to remove surface dirt. It also included a warning about washing with detergents, which is a method that many people advise for removing surface pesticide residue.

Consumers should not wash fruits and vegetables with detergent or soap. These products are not approved or labeled by the Food and Drug Administration for use on foods. You could ingest residues from soap or detergent absorbed on the produce.

So, based on news that pesticides on food may be a contributor to ADHD, and because the President’s Cancer Panel says chemical pollution, including chemicals found in foods, is causing preventable cancer, how can you limit your exposure to residual pesticides left on food? Here are few suggestions, but they are only suggestions. I don’t claim to have the miracle answer.

  • Buy as many fruits and vegetables as you can organically. Chemical pesticides and fertilizers are not used on organic produce.
  • Check out the Environmental Working Groups Shopper’s Guide to Pesticides in Foods. You can determine which produce has the highest levels of pesticide residue and choose to buy them organically or avoid them. You can also determine which produce has the lowest amount and serve them more frequently.
  • Choose frozen or canned fruits and vegetables over fresh. I know this sounds contradictory to what we’ve been taught about fresh produce being the healthiest, but in research on the USDA website, I found this one piece of information from a study titled USDA Pesticide Data Program. (Note that they cite canned green beans and spinach as exceptions — there may be other exceptions not mentioned.)
    "Generally, samples with detectable pesticide residues were less abundant in processed foods where extensive washing, processing and /or heating is expected to remove or reduce residues. Notable exceptions of canned green beans and canned spinach demonstrate that some residues are more tolerant of processing than others presumably based on the chemical stability."
  • Based on the previous information about extensive washing, processing and/or heating, it seems that thorough washing of the surface of fruits and vegetables before eating may be helpful. A solution of one part vinegar to nine parts water is often recommended as a natural produce wash. Wash thoroughly and scrub with a vegetable scrubber. Be aware that pourus fruits and vegetables may take on a vinegar taste/odor.
  • It also seems as if perhaps boiling vegetables and fruit may be helpful also, but I don’t think there is enough information there to really draw that conclusion.
Above all, don’t freak out. The study linking ADHD with pesticides wasn’t conclusive. In fact, the study said that the pesticides might come from drinking water or air breathed (I know — I probably just gave you another reason to freak out, right?). Reducing your family’s exposure to pesticides in food is a good idea for many reasons, and there are measures you can take. Boiling the food just probably isn’t one of them.

Readers, if you can point us to any reliable sources, in print or on the Web, that talk about how to remove pesticide residue from produce, please share them in the comments.

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Robin Shreeves ( @rshreeves ) focuses on food from a family perspective from her home base in New Jersey.

Limiting pesticide exposure from produce
A reader asks about removing pesticides from produce. Unfortunately, the answer is not clear.