Potatoes, Blackberries Added to List of Most Pesticide-Contaminated Produce: EWG

Blackberries were found to contain a pesticide that can harm the nervous system of fetuses, the Environmental Working Group said.

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Blackberries and potatoes have been added to the Environmental Working Group’s (EWG’s) “Dirty Dozen” list of the most pesticide-contaminated fruits and vegetables in 2025, the research and advocacy group said in a June 11 statement.

The EWG analyzed 47 foods for pesticides. In 2023, the Department of Agriculture (USDA) tested blackberries for the first time, finding there was at least one pesticide in 93 percent of the blackberry samples, the EWG said in another statement, adding that more than 80 percent of the samples had two or more pesticides.

“The most common pesticide found on blackberries was cypermethrin, detected on just over half of conventional samples. This synthetic pyrethroid insecticide is classified by the Environmental Protection Agency as a possible human carcinogen,” the group said.

“Pyrethroid insecticides are also known to cross the placenta and harm the nervous system of the developing fetus. Cypermethrin in particular disrupts thyroid hormones, which are critical to brain development. Early exposure can lead to behavioral and attention deficit disorders.”

Potatoes were added to the Dirty Dozen list due to a high concentration of plant growth regulator chlorpropham, the EWG said.

Chlorpropham is used to prevent potatoes from sprouting during storage. The chemical is banned in the European Union due to health concerns. In USDA’s tests, chlorpropham was found in 90 percent of potato samples, according to the EWG.

Animal studies have shown exposure to chlorpropham can trigger changes in blood cells and cause harm to the thyroid, the EWG said, adding there were peer-reviewed studies suggesting the chemical could disrupt hormones, though this assertion requires more research.

The 10 other items on the EWG’s Dirty Dozen list are blueberries; apples; pears; nectarines; cherries; peaches; spinach; strawberries; grapes; and kale, collard, and mustard greens.

The Dirty Dozen list is part of the EWG’s 2025 “Shopper’s Guide to Pesticides in Produce,” a report published annually. Included in the guide is the EWG’s “Clean Fifteen” list, which lists out the least pesticide-contaminated items.

“EWG recommends shoppers seeking fresh produce with low pesticide residues buy organic versions of items on the EWG’s Dirty Dozen and either organic or conventional versions of produce on the Clean Fifteen,” said EWG Senior Scientist Alexa Friedman.

Trump Administration on Pesticides

The 2025 EWG Dirty Dozen list has been published at a time when the presence of pesticides in foods is a key discussion topic under the current administration.

On May 22, the Make America Healthy Again Commission, chaired by Health Secretary Robert F. Kennedy Jr., published its first report, which cited higher exposure to chemicals such as pesticides as one of the factors likely contributing to the surge in childhood chronic diseases.

The report revealed that pesticides have been detected in the blood and urine of pregnant women and children. Some studies raise concerns about potential links between pesticides and “adverse health outcomes,” the report stated, while adding that studies on humans are limited.

Despite admitting to the risk of pesticide exposure, the commission recommended “thoughtful consideration” regarding any future course of action.

“American farmers rely on these products, and actions that further regulate or restrict crop protection tools beyond risk-based and scientific processes set forth by Congress must involve thoughtful consideration of what is necessary for adequate protection, alternatives, and cost of production,” the commission said in the report.

The National Corn Growers Association criticized the report, saying it was filled with “fear-based rather than science-based misinformation about pesticides.”

“We are deeply troubled that claims of this magnitude are being made without any scientific basis or regard for a long history of EPA expert evaluations of these products,” it said, referring to the Environmental Protection Agency.

In a May 22 statement, the Center for Food Safety said it applauds the report for mentioning the overuse of pesticides and acknowledging the harm the chemicals pose to children.

“Protecting children’s health and building a healthy food system must trump pesticide corporations’ profits,” George Kimbrell, the legal director of the group, said. “Policy and governance must be based on sound science and reject fearmongering and lobbying influence alleging that these toxins are needed for a healthy food system or agricultural economy.”