Strawberries continue to lead the “Dirty Dozen” list of fruits and veggies that contain the highest levels of pesticides, followed by spinach, a trio of greens – kale, collard and mustard – nectarines, apples, and grapes, according to the Environmental Working Group’s 2021 Shopper’s Guide to Pesticides in Produce.
Cherries came in seventh on the list of the 46 most contaminated foods, followed by peaches, pears, bell and hot peppers, celery, and tomatoes.
Avoiding pesticides is especially critical for babies and children, experts say, because of the damage they 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.
The report also offers consumers a list of the “Clean Fifteen” – foods with the least amount of pesticides. Nearly 70% of the “Clean” fruit and vegetable samples had no pesticide residues, making them a safer choice, EWG says.
“Multiple pesticide residues are extremely rare on Clean Fifteen vegetables,” the EWG report stated. “Only 8 percent of Clean Fifteen fruit and vegetable samples had two or more pesticides.”
Vegetables on this list include sweet corn, onions, frozen peas, eggplant, asparagus, broccoli, cabbage, cauliflower and mushrooms.
The guide’s cleanest fruits include pineapple, papaya, kiwi, honeydew melon, cantaloupe and avocado (yes, it’s a fruit). Avocados and sweet corn were the least contaminated, the report found, with less than 2% of samples showing detectable pesticide residue.
“It’s a really great resource,” said Jane Houlihan, the national director of science and health for Healthy Babies Bright Futures, a coalition of advocates committed to reducing babies’ exposures to neurotoxic chemicals.
“By nature pesticides are toxic, and doing what you can to reduce exposures is a really good idea to protect your family’s health,” said Houlihan, who was not involved with the report.
“That’s where the ‘Clean Fifteen’ list is particularly useful,” said Dr. Leonardo Trasande, chief of environmental pediatrics at NYU Langone, who was not involved in the report.
“It can give families reassurance that what they are buying, even if it’s conventionally farmed, may not pose the same level of concerns from pesticides,” Trasande said.
An annual report
The EWG report, issued yearly since 2004, uses US Department of Agriculture test data to rank 46 foods that are the most and least contaminated with pesticide residues. The agency prepares 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.
A new entry on this year’s list was collard greens and mustard greens, which joined kale in the No. 3 spot. Tests found these vegetables often contained the pesticide DCPA, classified by the EPA as a possible human carcinogen. It was banned by the European Union in 2009.
“The other new big thing on the list is bell and hot peppers, which came in at No.10. They haven’t been tested since 2011-2012, and the USDA found 115 different pesticides on last year’s pepper crops. This is the most, by far, of any of the crops tested,” said EWG toxicologist Thomas Galligan.
Peppers, along with “Dirty Dozen” members oranges, apples, grapes and cherries, are often contaminated with chlorpyrifos, a pesticide originally created as an alternative to DDT.
“Chlorpyrifos should be banned in the US, as it is in Europe. It’s neurotoxic and harms children’s brain development,” Houlihan said.
Chlorpyrifos was slated to be permanently banned in the US in 2016 when EPA safety experts determined it was harming children and farm workers. One study, for example, found lasting structural changes in the brains of pre-teen children who had been highly exposed to chlorpyrifos in utero.
“That decision was overturned under the Trump administration, and chlorpyrifos was allowed to remain in use,” said EWG toxicologist Alexis Temkin. “Several states have taken action to ban it, including California, Hawaii, New York and Oregon. So we’re seeing a lot of movement at the state level, due to the federal shortcomings.”
On January 20, the Biden administration put chlorpyrifos on their list of Trump administration actions to review in order to protect the public health.
Pesticides remain, even after peeling
While kid-favorite citrus fruits like clementines and tangerines ranked No. 20 and oranges came in at No. 24 on the overall list, EWG did independent testing on citrus fruits this year, and found two fungicides, imazalil and thiabendazole, were widespread.
“Evidence exists that they have the potential to disrupt the hormone system, and one is suspected of causing cancer,” Houlihan said.
Imazalil, a fungicide used after harvest to keep fruits from molding on the way to market, was found on almost 90% of all the grapefruit, oranges, mandarins and lemons tested early this year by an independent laboratory commissioned by EWG. The USDA found the same fungicide on over 95% of tangerines tested in 2019.
Most startling – the flesh of the fruits was tested after they were peeled.
“I have said repeatedly that that fruits and vegetables with rinds that you don’t eat are less problematic,” Trasande said. “I’m quite frankly surprised and concerned that you can see fungicides penetrate to that level.”
Why would fungicides be needed after fruit is harvested? Partly to satisfy the picky American consumer, Trasande said.
“We live in an age where we like to see beautiful fruits and vegetables,” he said. “And we expect, as consumers, to almost have that perfect, almost photoshopped image in the grocery aisle.
“Some decay doesn’t necessarily mean loss in nutritional value, or even any safety hazard,” Trasande added. “Those fungicides are really there to make the consumer feel better about buying a product.”
CNN reached out to CropLife America, a national trade association that represents the manufacturers, formulators and distributors of pesticides, for comment on this year’s report.
“Scaring Americans away from eating foods that are a safe and vital part of our diet is a disservice to public health,” said CropLife America President and CEO Chris Novak, in a statement.
“The benefits of a diet rich in fruits and vegetables outweigh any possible risks from exposure to pesticide residues,” Novak said. “Federal regulators monitor our food for pesticide residues, ensuring produce and other foods are safe to eat. CLA supports the choice of consumers to purchase food grown using any farming method to promote a healthy lifestyle.”
EWG agrees that eating a variety of fruits and vegetables is key to a healthy diet,
“A diet that’s high in fruits and vegetables is a healthy diet, so that’s the most important thing,” said EWG’s Galligan. “Our general guidance is to recommend that consumers choose organic whenever possible, especially for the items on the Dirty Dozen list.
“We do recognize that some people can’t afford or don’t have access to organic food, and that’s why we create our Clean Fifteen list as well so they can choose non-organic foods with the least amount of pesticides,” Galligan said.
Pesticide Data Program reports issued by the US Department of Agriculture typically indicate that when pesticide residues are found on foods, they are nearly always at levels below the human tolerance limits set by the agency.
While most pesticide residues do fall within the USDA government-mandated restrictions, that doesn’t mean they are safe, EWG said.
What to do?
Besides eating exclusively from the “Clean Fifteen” list of the least contaminated foods, experts suggest the following tips.
Eat a wide variety of fruits and vegetables. Serving a wide variety of fruits and vegetables, regardless of which list they’re on, is a key recommendation.
“It’s really important, not only from the perspective of making sure you’re getting a variety of nutrients, but also from the perspective of making sure you’re not concentrating any particular pesticide in your family’s diet,” Houlihan said.
Always wash before eating. “Washing with water is the best way to remove surficial pesticide residues. California routinely tests washed and unwashed produce samples, and finds higher pesticide amounts on unwashed samples, on average,” Houlihan said.
The US Food and Drug Administration recommends against washing fruits and vegetables with soap, detergent, or commercial produce wash.
“Produce is porous. Soap and household detergents can be absorbed by fruits and vegetables, despite thorough rinsing, and can make you sick. Also, the safety of the residues of commercial produce washes is not known and their effectiveness has not been tested,” the FDA said.
Eat organic when possible. While organic foods can be exposed to pesticides – and can certainly contain toxic metals found in soil – clinical trials have found people who moved to organic foods saw “rapid and dramatic reductions” in the levels of pesticides in their urine, a common test for pesticide exposure.
“Eating organic reduces your level of pesticides in urine, whether you are high income or low income, studies have been done in both,” Trasande said.
Buy local and in season. “Farm-to-table” – a term that describes food that is locally sourced and purchased directly from a farmer or producer, is not only popular in homes and restaurants, it can cut down on pesticide use, experts say.
Prices drop when fruits and vegetables are in season and plentiful, and targeting in-season items is a good way to stock up on organic foods – especially those on the “Dirty Dozen” list – that might be more expensive at other times.
Get CNN Health's weekly newsletter
Sign up here to get The Results Are In with Dr. Sanjay Gupta every Tuesday from the CNN Health team.
Freeze or can organic foods. Overfill your shopping cart with organic fruits and vegetables on sale or in season, experts suggest, and then prep and freeze or can them for future use.
Advocate for change. Action by consumers is key to change, experts say.
“It’s no secret that we’ve seen other industries change their manufacturing process in the US due to consumer activism,” Trasande said. “Call attention to the ‘Dirty Dozen’ report and ask companies for accountability, ask for their testing data on fruits and vegetables.”
“I think that can go a long way and get companies to compete with each other on something consumers value – safety for themselves and for their children.”