Healthy or high risk? New analysis warns of pesticide residues on some fruits and veggies

Several types of fruits and vegetables generally considered to be healthy can contain levels of pesticide residues potentially unsafe for consumption, according to an analysis conducted by Consumer Reports (CR) released on Thursday.

The report, which is based on seven years of data gathered by the US Department of Agriculture (USDA) as part of its annual pesticide residue reporting program, concluded that 20% of 59 different fruit and vegetable categories included in the analysis carried residue levels that posed “significant risks” to consumers of those foods.

Those high-risk foods included bell peppers, blueberries, green beans, potatoes and strawberries, according to CR. The group found that some green beans even had residues of an insecticide called acephate, which has been banned for use on green beans by US regulators since 2011. In one sample from 2022, levels of methamidophos (a breakdown product of acephate), were more
than 100 times the level CR scientists consider safe. In another sample, acephate levels were 7 times higher than CR considers safe.

Overall, out of the nearly 30,000 total fruit and vegetable samples for which CR examined data, about 8% percent were deemed to have residues at “high risk or very high risk”. Imported produce was more likely to carry high levels of pesticide residues than domestically supplied foods, the report said, noting that residue levels can vary widely from sample to sample.

The results “raise red flags,” according to CR. The report advises that children and pregnant women should consume less than a serving a day of high-risk fruits and vegetables, and less than half a serving per day of “very high-risk ones.”

“People need to be concerned because we see that the more data we gather on pesticides, the more we realize the levels that we previously thought to be safe turn out not to be,” said Michael Hansen, a senior scientist at CR who was recently appointed to a USDA food safety advisory committee.

The organization said the “good news” is that the data showed residues in most of the foods sampled, including 16 of 25 fruit categories and 21 of 34 vegetable types, presented “little to worry about.” Nearly all organic samples showed no concerning levels of pesticide residues.

The report suggests consumers “try snap peas instead of green beans, cantaloupe in place of watermelon, cabbage or dark green lettuces for kale, and the occasional sweet potato instead of a white one.”

Faulty safety assurances  

In coming to its findings, CR said it analyzed USDA residue test results for 29,643 individual food samples and then rated the risk of each fruit or vegetable based on how many different pesticides were found in each, how frequently and at what levels the residues were found, and the toxicity for each pesticide detected.

For pesticides known to be cancer-causing, neurotoxins or endocrine disruptors – chemicals that can alter the hormonal functions – CR added an extra safety margin requirement to the levels considered safe. 

The CR said its safety levels differ from those set by the Environmental Protection Agency (EPA), which establishes “maximum residue limits” (MRLs) for each crop use of a pesticide after developing a risk assessment that the agency says considers multiple factors, including aggregate exposure from the pesticides, cumulative effects of related pesticides, and potential increased increased susceptibility to infants and children. 

Based on the EPA’s MRLs, the USDA said in its most recent pesticide data program report that 99% of foods tested had residues within the safety limits. But the EPA’s limits are too high to be truly protective of public health, and do not adequately account for the risks associated with some pesticides, according to CR.

“EPA stands by its comprehensive pesticide assessment and review process to ensure the safety of the U.S. food supply,” the agency said in a statement. “Since the pesticide registration review program started in 2006, EPA has cancelled some or all uses in nearly 25% of the conventional pesticide cases it has completed work on, where new science indicates a need for additional mitigations.” The EPA says it considers “all relevant data” in making human health risk assessments for pesticide use. 

It is common for many farmers to apply a range of pesticides, including herbicides, insecticides and fungicides, on their fields as a means to fight weeds, bugs and plant diseases. In some cases, they spray the chemicals directly over growing plants. Residues of these chemicals are found not only in food but often in drinking water as well. 

Both the Food and Drug Administration and the USDA have been tracking levels of pesticide residues in foods for decades, and have repeatedly assured the public that those residues are not a human health risk as long as they do not exceed the EPA’s MRLs. 

But those assurances have proven wrong in the past. In one example, the government long said the insecticide chlorpyrifos was safe to be used on food if residues were within the EPA’s established limits, despite strong scientific evidence that exposure could harm the brains and nervous systems of developing children.

In 2015, after decades of use in agriculture, the EPA changed its stance, saying it could not determine if chlorpyrifos in the diet was actually safe, and proposed banning the pesticide from use in farming. It took until 2021 for the agency to issue a final rule banning the pesticide, and a court challenge to the ban has kept the chemical in use.

Further undermining faith in the government’s assurance on pesticide residues is the fact that the EPA consults with the companies selling the chemicals in setting allowable residue levels, and those allowable levels can be increased at the request of the companies.  

The EPA has approved several increases allowed for residues of the weed killing chemical glyphosate, for instance. Glyphosate, the active ingredient in Roundup herbicides, is classified as a probable human carcinogen by the International Agency for Research on Cancer but the EPA considers it not likely to cause cancer.

Industry influence

The Food Quality Protection Act (FQPA) requires the EPA to apply an additional tenfold safety margin to allowable exposure levels to account for the effects on vulnerable infants and children, and allows the agency to skip adding the safety margin “only if it will be safe for infants and children.” The agency has declined to apply that additional tenfold margin of safety for infants and children when setting the legal levels for several pesticide residues, however, even when scientists have said it is needed.

Pesticide manufacturers have successfully pushed the EPA not to apply the extra safety margin for dozens of pesticides that have “clear potential to damage DNA or disrupt development,” said Chuck Benbrook, a pesticide residue expert and a consultant on the CR report. 

“EPA has known about the existence of thousands of excessively high tolerances since the 2000s,” said Benbrook. “Despite the powerful new tools and mandate in the FQPA to lower or revoke them, the pesticide industry makes it very difficult for the EPA to lower tolerances and progress has slowed to a crawl. Even worse, some very-high pesticides are finding their way back on the market and into children’s food.”

Government and industry assurances about the safety of pesticide residues in the US food supply are based on the fact that most residues in food are below the applicable tolerance levels, Benbrook added.

“But we now know, and can specifically identify hundreds of samples of food each year with below-tolerance residues that pose risks far above what the EPA regards as safe,” he said.

“Action needs to be taken”

The CR report says the dangers lurking on grocery stores shelves could be reduced by the elimination of two chemical classes – organophosphates and carbamates. While organophosphates are used in plastic and solvent manufacturing as well as pesticides, they are also constituents of nerve gas, and exposure – acute and long-term – can have a range of harmful impacts on people and animals.

As the Illinois Department of Public Health explains: “Organophosphates kill insects by disrupting their brains and nervous systems. Unfortunately, these chemicals also can harm the brains and nervous systems of animals and humans.”

Carbamates bear a chemical similarity to organophosphate pesticides.

The CR report comes as many scientists have increasingly been questioning whether or not a steady diet of pesticide residues can actually be safe for people and what long-term consumption of trace amounts of pesticides in food could be doing to human and animal health.

“The data is showing more and more that these lower levels are having an impact,” said Hansen. “That is why some action needs to be taken.”  

(Featured photo by Raul Gonzalez Escobar on Unsplash.)