pesticides on food

Asked June 25, 2017, 7:16 PM EDT

I hear a lot about pesticides on fruits and vegetables. Does washing with soap and water remove them? How about peeling? Would canned be a better choice than fresh? Thanks

Multnomah County Oregon

1 Response

Thanks for your question about pesticides and food. In order to answer it, we need to break down both pesticides and fruits/vegetables into separate categories, because the concerns and solutions may differ.

1. Some pesticides are what is called 'systemic.' That means that the chemical (and it may be made in an industrial plant or come from organic materials) is taken into the plant--typically through the roots--and becomes a part of every cell in the plant. The EPA has, historically, only licensed pesticides for use around edible plants if it finds no risk of poisoning or causing cancer, etc. If the farmer is following the label rules, none of the non-approved systemic pesticides get applied to or near the foods. But, once a systemic is in the plant--legally or by mistake--washing won't remove it from the plant. It will become a part of you, and either get washed out of your system (eventually) or become a part of your cells.

2. A topical pesticide, on the other hand, is applied to the stems, leaves, flowers and fruits. These, too, can be manufactured or be organic (derived from organisms.) Because they're not taken into the plant structure, and operate only on the 'skins' of the plant, they can be washed off. This reputable source recommends washing with a salt water mixture, but that won't remove the systemic pesticides.

3. A third element in the answer is the question of what part of the plant are you eating? If a plant has been treated with a systemic pesticide, just removing the peel or rinsing won't remove the pesticide. On the other hand, if only a topical pesticide has been used, and you peel it--like an apple--or you don't eat the outside--like a watermelon or avocado or artichoke--then you aren't at risk of ingesting any pesticide, and needn't rinse with salt water. But there are lot of fruits (they have seeds) and vegetables (they don't have seeds) that we don't peel, and washing is recommended.

4. The final part of the equation is what you choose to buy or grow. You can grow organic food. No pesticides; let the insects eat their fill; use only organic (such as Neem oil or insecticidal oils and soaps) to eliminate the insects and diseases that reduce your harvest below your tolerance point. Or, you can spend a bit more and buy organic food at your farmer's market or local grocery. There are legal guidelines which govern those who advertise they 'grow organic.' That doesn't mean you shouldn't rinse them, as well, but at least addresses what they certify that they're using.

5. When you buy canned food, the same issues prevail. They either washed them before processing or they didn't. If the can (or freezer package or bottle) doesn't say "certified organic" then you have no way of knowing what pesticides reside in the food.

I have been unable to find a science-based (as in Agricultural School) article on this specific issue. However, this article from the Environmental Working Group, which is summarized in this link, tells you which type of fresh (and a few frozen) foods have the most to least amount of detectable pesticides.

I hope this is helpful information to you. Good luck!