Strawberries and spinach continue to top the annual list of the “Dirty Dozen” fruits and veggies that contain the highest levels of pesticides, followed by three greens – kale, collard and mustard – nectarines, apples, grapes, and bell and hot peppers, according to the Environmental Working Group’s 2022 Shopper’s Guide to Pesticides in Produce.
Cherries came in eighth this year on the list of the 12 most contaminated foods, with peaches, pears, celery and tomatoes rounding out the list.
But don’t stop eating these foods, which are full of the vitamins, minerals, fiber and antioxidants needed to battle chronic disease, experts say.
“If the things you love to eat are on the ‘Dirty Dozen’ list, we recommend buying organic versions when you can,” said Alexis Temkin, a toxicologist at the EWG with expertise in toxic chemicals and pesticides.
“Several peer-reviewed studies and clinical trials have looked at what happens when people switch to a fully organic diet,” she said. “Concentrations and measurements of pesticides decrease very rapidly.”
Consumers can also consult EWG’s “Clean Fifteen” – a list of produce with the least amount of pesticides. Nearly 70% of the fruits and veggies on the list had no detectable pesticide residues, while just under 5% had residues of two or more pesticides, the report said.
Avocados had the lowest levels of pesticides among the 46 foods tested, followed by sweet corn, pineapple, onions and papaya.
“Even a brief exposure to pesticides which alter endocrine function can cause permanent effects if the exposure occurs during critical windows of reproductive development”
Issued yearly since 2004, the EWG report uses US Department of Agriculture test data to rank 46 foods that are the most and least contaminated with pesticide residues. The USDA staffers prepare the food as consumers would – washing, peeling or scrubbing – before testing each item.
The USDA does not sample all 46 foods each year, so EWG pulls results from the most recent testing period. Strawberries, for example, have not been tested by the USDA since 2016, Temkin said,
Many samples of the 46 fruits and vegetables included in the report tested positive for multiple pesticides, including insecticides and fungicides. Over 90% of “strawberries, apples, cherries, spinach, nectarines and grapes tested positive for residues of two or more pesticides,” the report said.
Testing found the highest level of multiple pesticides – 103 – on samples of the heart-healthy trio of kale, collards and mustard greens, followed by 101 different pesticides on hot and bell peppers. In general, “spinach samples had 1.8 times as much pesticide residue by weight as any other crop tested,” the report said.
Being exposed to multiple pesticides, even at low levels, is “supra-additive,” with each pesticide having more of a health impact than it might in isolation, said Dr. Leonardo Trasande, chief of environmental pediatrics at NYU Langone, who was not involved in the report.
Health risks of pesticides
Health dangers from pesticides depend on the type, according to the US Environmental Protection Agency. Pesticides can impact the nervous system, irritate the eyes and skin, interfere with the hormonal systems of the body, or cause cancer, the EPA said.
The pesticide DCPA, classified by the EPA as a possible human carcinogen and banned in 2009 by the European Union, was frequently detected on collards, mustard greens and kale, the EWG report said.
Chlorpyrifos, a pesticide often used on nut and fruit trees and row crops such as broccoli and cauliflower, was banned by the EPA in February 2022 after a 15-year effort by environmental groups.
Chlorpyrifos contains an enzyme “which leads to neurotoxicity, and has also been associated with potential neurodevelopmental effects in children,” the EPA said.
Babies and children are especially vulnerable to pesticides, experts say, because of the damage the chemicals can cause to the developing brain. A 2020 study found an increase in IQ loss and intellectual disability in children due to exposure to organophosphates, a common class of pesticides.
A large number of pesticides also affect the endocrine system in developing fetuses, which can interfere with developmental growth, reproduction and metabolism.
“Even a brief exposure to pesticides which alter endocrine function can cause permanent effects if the exposure occurs during critical windows of reproductive development,” according to the EPA.