Pesticides in vegetables and fruit? What has the most, and what has the least?

Juicy, plump tomatoes. Lush, leafy kale.

The summer growing season is upon us. Everywhere you look -- from supermarkets, to farmers' markets, to your own backyard --  fruits and vegetables abound. 

We all know a healthy diet requires lots of fresh produce. We also know it's best to minimize our exposure to carcinogenic pesticides, herbicides and fungicides. This is especially important for children, according to the American Academy of Pediatricians Council on Environmental Health. Buying organic produce is one way to do that, but not everybody can afford to buy all organic, all the time.

Each year, the Environmental Working Group, a non-profit, non-partisan research organization, presents its "Shopper's Guide to Pesticides in Produce," which ranks the pesticide contamination of 47 popular fruits and vegetables. The guide, first released in 2004, is based on results of more than 40,900 samples of produce tested by the U.S. Department of Agriculture and the Food and Drug Administration.

For 2019, the EWG found strawberries, spinach and kale to be the most contaminated, while avocados, sweet corn and pineapples had the least pesticide residue.

“We were surprised kale had so many pesticides on it, but the test results were unequivocal,” said Alexis Temkin, a toxicologist for EWG, in a press release.

"When it comes to some conventionally grown produce items, such as kale," Temkin added, "choosing organic may be a better option.”

According to the EWG report, more than 92 percent of conventionally grown kale samples from the USDA's most recent tests had at least two or more pesticide residues.

However, the Alliance for Food and Farming, a non-profit organization that represents conventional and organic farmers, notes that the U.S. Department of Agriculture's Pesticide Data Program and the Food and Drug Administration's residue sampling program each found that 99 percent of produce sampled met or surpassed EPA safety levels.

The AFF cites peer-reviewed studies that conclude that pesticide residue on conventionally grown produce should not concern consumers. 

Both the AFF and the EWG agree that the nutritional benefits of fruits and vegetables outweigh the risks of pesticide residue. 

Experts disagree on whether pesticide residue can be removed by rinsing or soaking produce, but all produce -- organic or conventional -- should be rinsed to help remove dirt, insects and bacteria.

Home gardeners can avoid pesticide residue simply by not using pesticides. But they also should employ best practices to prevent diseases that weaken plants and make them more susceptible to pests. 

"There are a lot of cultural ways to deal with disease," said Diane Larson, a horticulturalist for the Rutgers Cooperative Extension, which studies agricultural issues and provides information to the public.

First and foremost, heed the weather, Larson advised.

"Turn your sprinkler system off," she said. "Too much water creates problems. We've had a lot of rain, and if you've been watering on top of that, you will have disease problems like crazy."

"With tomatoes, keep the water off the leaves, because fungus grows there," Larson said. "Use drip irrigation, or water close to the roots. Space out your tomatoes so that there is good ventilation between plants."

Who is in the Dirty Dozen?

Here is the EWG's "Dirty Dozen," the produce that was found to have the highest levels of pesticide residue:

1. Strawberries

2. Spinach

3. Kale

4. Nectarines

5. Apples

6. Grapes

7. Peaches

8. Cherries

9. Pears

10. Tomatoes

11. Celery

12. Potatoes

And here is the "Clean Fifteen," the top 15 types of produce least contaminated by pesticides. More than 70 percent of the samples of these fruits and vegetables had no pesticide residue:

1. Avocadoes

2. Sweet corn

3. Pineapple

4. Sweet peas (frozen)

5. Onions

6. Papayas

7. Eggplants

8. Asparagus

9. Kiwis

10. Cabbages

11. Cauliflowers

12. Cantaloupes

13. Broccoli

14. Mushrooms

15. Honeydew melons

Hi, there! I'm Kelly-Jane Cotter. I'm running out of sunny spots in my back yard garden, but I always make sure to plant tomatoes (this year: Cherokee, Juliet and Better Boy). Read more of my stories below, follow me@KellyJaneCotter, reach me at kcotter@gannettnj.com, and please consider asubscriptionto support local journalism.

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