You may want to put the green juice down for this one.
Kale ranked as a third-worst fruit or vegetable behind strawberries and spinach when it comes to pesticide contamination, according to the Environmental Working Group’s annual “Dirty Dozen” report. Over 92% of kale samples were found to have two or more pesticide residues — and a single piece of kale could have up to 18 pesticides on or in it.
One of the pesticides commonly found with kale was Dacthal, or DCPA. The pesticide, which is banned in Europe and was classified by the Environmental Protection Agency as a possible carcinogen, was found on nearly 60% of the kale samples tested.
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Here is the full list of the “Dirty Dozen” fruits and vegetables:
. Strawberries . Spinach . Kale . Nectarines . Apples . Grapes . Peaches . Cherries . Pears . Tomatoes . Celery . PotatoesThe Environmental Working Group’s ranking is based on an analysis of test data from the U.S. Department of Agriculture. USDA personnel test fruits and vegetables for pesticide residues regularly, making sure to replicate how shoppers would consume the product. For instance, if consumers regularly wash and peel a fruit before eating it, the USDA testers will do that before examining the product for pesticides.
The USDA changes the batch of fruits and vegetables it tests based on consumers’ eating habits. As such, kale had not been examined in nearly a decade. The last time the USDA included kale in its testing, from 2006 to 2008, the leafy green ranked No. 8 on the Environmental Working Group’s Dirty Dozen list.
In those intervening years, kale has becoming an increasingly popular food, particularly among health-conscious consumers. A growing number of food products now contain kale as an ingredient, and scientists are even working to create a tastier version of the broccoli relative.
Consumers should opt for organic food whenever possible to reduce their exposure to pesticides, experts say.
But the vegetable’s soaring popularity isn’t necessarily to blame for its propensity for pesticide contamination. “Some of the changes could be due to more harvesting of kale, it could also be due to analytical methods changing when we’re testing,” said Alexis Tremkin, a toxicologist at the Environmental Working Group.
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Another factor could be how kale is grown. Dacthal, the potentially carcinogenic pesticide, is typically applied directly to soil as a weed-killer. Because it’s in the soil, it can then be absorbed into the plant itself, said Carla Burns, a research analyst at the Environmental Working Group . Growing practices like this may explain the pesticide contamination that’s endemic to much of the “Dirty Dozen” fruits and vegetables.
Altogether, some 70% of the conventionally-grown produce sold in the U.S. has pesticide residues, according to the report. However, consumers should stop eating fruits and vegetables as a result.
Instead, consumers should opt for organic food whenever possible to reduce their exposure to pesticides, experts say. And when that’s not feasible, they should opt instead for fruits and vegetables that are less likely to be contaminated.
The Environmental Working Group also released its annual “Clean Fifteen” produce list. Less than 30% of those fruits and vegetables have pesticide contamination, based on the USDA’s testing. The “Clean Fifteen” includes the following:
. Avocados . Sweet corn . Pineapples . Frozen sweet peas . Onions . Papayas . Eggplants . Asparagus . Kiwis . Cabbages . Cauliflower . Cantaloupes . Broccoli . Mushrooms . Honeydew melonsGet a daily roundup of the top reads in personal finance delivered to your inbox. Subscribe to MarketWatch's free Personal Finance Daily newsletter. Sign up here.
