Key Takeaways:
- Eating high-residue produce raises pesticide levels in people.
- Spinach tops 2025’s “Dirty Dozen” with the most residue.
- Choose “Clean Fifteen” items or organic to cut exposure.
Fruits and vegetables are essential for good health — but a new study finds that some popular produce may deliver more than vitamins and fiber. It may also raise levels of dozens of pesticides in the body.
Researchers with the Environmental Working Group (EWG) compared pesticide residues found on fruits and vegetables by the U.S. Department of Agriculture with urine samples from people in the National Health and Nutrition Examination Survey. The results, published in the International Journal of Hygiene and Environmental Health, revealed a clear pattern: people who ate more high-residue produce had higher pesticide levels in their urine.
“We found consuming different types of fruits and vegetables changes your pesticide levels accordingly,” said Alexis Temkin, EWG’s vice president of science and lead author of the study. “Greater consumption of the higher-residue foods increased pesticide levels more than lower-residue foods.”
Linda Birnbaum, former director of the National Institute for Environmental Health Sciences, said the findings show just how directly diet influences exposure. “This tells us that when people eat a lot of produce with high residues of pesticides, they’re more likely to have elevated levels in their urine,” she said. Importantly, Birnbaum noted, the study looked at the combined effects of multiple pesticides, not just one chemical at a time.
Health Concerns
Scientists have long warned that pesticides can be linked to health problems ranging from premature birth and birth defects to reduced sperm counts, heart disease, and cancer. Children are considered especially vulnerable. The American Academy of Pediatrics cautions that exposure during pregnancy may raise the risk of low birth weight, birth defects, or fetal death, while exposure in childhood has been tied to learning problems and cancer.
Industry representatives counter that current safety standards are strong. “Contrary to the study’s claims, the EPA evaluates the combined exposure to multiple pesticides … while also considering the risks to vulnerable populations,” said Manojit Basu of CropLife America, a group representing pesticide producers.
The “Dirty Dozen” and “Clean Fifteen”
The findings lend support to EWG’s annual Shopper’s Guide to Pesticides in Produce, which lists the most and least contaminated foods. In the 2025 report, 203 pesticides were found across the “Dirty Dozen,” with spinach topping the list for the heaviest pesticide residue by weight. Strawberries, kale (including mustard and collard greens), grapes, peaches, cherries, nectarines, pears, apples, blackberries, blueberries, and potatoes rounded out the list.
The most toxic mix of pesticides was identified in green beans, spinach, peppers, and leafy greens. On the other end of the spectrum, pineapples ranked cleanest, followed by sweet corn, avocados, papaya, onions, peas, asparagus, cabbage, watermelon, cauliflower, bananas, mangos, carrots, mushrooms, and kiwi.
Reducing Exposure
Temkin emphasized that the answer is not to avoid fruits and vegetables altogether. Instead, she suggested choosing items from the “Clean Fifteen” when possible, or buying organic versions of the most contaminated foods.
If organic isn’t an option, proper washing helps. USDA researchers wash produce before testing, but thorough rinsing at home can still reduce residue. The U.S. Food and Drug Administration recommends washing under running water, drying with a clean cloth, and scrubbing firm produce with a vegetable brush. Leafy greens should have their outer leaves removed and be rinsed gently.
Experts caution against bleach, soap, or commercial produce washes, which can leave their own residues. Bagged greens labeled “triple washed” do not require an additional rinse.
Even if you peel, you should still wash first, says the US Food and Drug Administration. All produce, even organic, should be washed before peeling so dirt and bacteria aren’t transferred from a knife onto the fruit or vegetable. After washing, dry with a clean cloth or paper towel.
Temkin said the study’s real value is in showing how diet directly shapes exposure: “Now, we have a method to estimate pesticide levels in an individual’s diet and then study any associated health effects.”