Calculating Pesticide Residue in Your Produce: Is It Worth It?

Because concerns over pesticide residue in fruits and veggies are growing, Healthnews looked at whether following Dirty Dozen, Clean Fifteen lists, or using pesticide residue calculators is worth the effort.

Fruit and vegetables are packed with the essential nutrients, antioxidants, and fiber humans need for optimal health. They promote heart health, support the immune system, and lower mortality risk. However, despite the numerous benefits of consuming a produce-rich diet, statistics show that only around 12% of adults in the United States get enough fruits and veggies to meet the advice set in the dietary guidelines for Americans.

According to the 2020 to 2025 Dietary Guidelines, adults should consume 1.5 to 2 cup-equivalents of fruits and 2 to 3 cup-equivalents of vegetables daily.

However, produce can also contain potentially harmful pesticide residue, so some believe choosing organic fruits and vegetables is safer. The problem is that organic foods are not entirely free of pesticides, either. They are typically more expensive than conventionally grown food as well, so "going organic" might not be in everyone's budget.

What are Dirty Dozen lists and pesticide residue calculators?

According to 2022 research, approximately 4.19 million metric tons of pesticides were used on crops worldwide in 2019. U.S. farmers used around 408,000 tons of these chemicals in the same year.

Concerns over the potential harmful effects of pesticide exposure through treated fruits and vegetables inspired the Environmental Working Group (EWG), an independent non-profit organization, to create its Shopper's Guide to Pesticides in Produce. The Guide includes Dirty Dozen and Clean Fifteen lists to help consumers choose produce with the least amount of pesticide residue.

While compiling the Dirty Dozen list for 2024, EWG found that 75% of non-organic produce and 95% of fruits and veggies on the list have residue from one or more pesticides.

AFF Executive Director Teresa Thorne tells Healthnews that the calculator is based on an analysis of the United States Department of Agriculture's (USDA) Pesticide Data Program (PDP) results by toxicologists with the University of California Personal Chemical Exposure Program.

"The analysis determined that a child could eat hundreds to thousands of servings of a fruit or vegetable in a day and still not have any adverse health effects from pesticide residues," Thorne says. "The AFF developed the calculator as a quick and easy way for consumers to see the results of the analysis and learn more about how very low residues are on fruits and vegetables, if residues are present at all."

The AFF's goal is to reassure consumers about the safety of all produce and encourage them to purchase fruits and vegetables that are affordable and accessible to them.

How does the pesticide residue calculator work?

Healthnews used the calculator to determine the number of servings of fruits and veggies on the Dirty Dozen list that a man, woman, teen, and child could eat without experiencing an adverse effect from pesticide residue.

Here's what we found:

Number one on the Dirty Dozen list is strawberries. According to the calculator, the average man could eat 635 servings of conventionally grown strawberries in one day without adverse effects from pesticide exposure. Moreover, a woman could consume 453 servings, a teen could eat 363 servings, and a child could consume 181 servings of strawberries without experiencing issues from residual pesticide intake.

This includes berries with the highest pesticide residue recorded by the USDA.

When comparing conventional produce to organic versions, the calculator shows that a man could consume 5,833 servings of conventionally grown lettuce per day without ill effects from pesticides, which is close to the 4,690 servings per day of organic lettuce.

Are the Dirty Dozen and Clean Fifteen lists flawed?

Thorne says peer-reviewed research has shown that EWG does not follow established scientific procedures when developing its Dirty Dozen list.

"Further, this research shows that EWG's recommendations to substitute organic forms of produce for conventional does not result in any decrease in consumer risk because residues on conventionally grown produce are so very low, if present at all," Thorne explains. "EWG themselves state that their list is not risk-based nor do they follow basic tenets of toxicology."

Still, EWG analyzes data used to create its lists from tests on 47,510 samples of nearly 50 fruits and vegetables conducted by the USDA and FDA. Based on the results of those tests, EWG identifies produce with the highest pesticide residues and puts them on the Dirty Dozen list.

The EWG also compiles a list of fruits and veggies with the least amount of pesticide residue — the Clean Fifteen — to provide concerned consumers with a choice.

However, according to Thorne, consumers need to understand pesticide safety limits.

"USDA sampling results year after year show that over 99% of the foods tested have residues well below EPA established safety limits," Thorne tells Healthnews. "Its recent report found that 27% [of foods] had no detectable residues at all."

Alexis Temkin, Ph.D., senior toxicologist with EWG, tells Healthnews, "Most pesticide residues found on fresh produce by federal agencies – whose test results EWG uses to compile its Shopper's Guide every year – fall below government limits and thus are legal. But legal limits don’t always represent what’s safe for human consumption."

Temkin says that numerous peer-reviewed scientific studies have shown that consuming produce high in pesticide residue increases the risk of certain negative health impacts in people.

"When regulating pesticides, the U.S. government considers them only one at a time," Temkin says. "Agencies don’t look at the potential total body burden for consumers. Yet studies often show that when animals are exposed to pesticides in a mixture, adverse effects often occur at doses lower than when they are exposed to only one pesticide at a time."

Is pesticide residue in food dangerous?

Research examining the health impacts of pesticide residue on produce have yielded mixed results. For example, recent study published in Environment International observed no signs that dietary exposure to pesticide residue was associated with increased mortality or that it dampens the benefits of consuming fruits and vegetables.

Still, the study's authors suggest that consuming fruit and vegetables with lower pesticide residue levels may be more beneficial.

Moreover, a 2022 study suggests that low-level chronic dietary pesticide exposure can impact the human gut microbiota.

Other reports suggest that pesticides are stored in fat before they are removed by the kidneys or liver and may build up as a person ages. Because of this, older adults may experience health problems from pesticide exposure.

In addition, scientists have found links between pesticide exposure and autism and low sperm counts in men.

Temkin says that children are particularly susceptible to many of the health harms associated with pesticide exposure.

"Peer-reviewed research released by EWG in 2020 found that the EPA fails to adequately consider children in setting allowable levels of exposure for 90 percent of the most common pesticides," Temkin explains. "EWG has asked the EPA to meet its legal requirement under the Food Quality Protection Act to protect children's health by applying an extra margin of safety when assessing risks from pesticides in food."

How to wash fruits and vegetables to remove pesticide residues

When the USDA and FDA prepare produce for testing, they wash, scrub, and peel the fruits and veggies much like a consumer would in their home kitchen. Even after these steps, the agency's tests showed that some produce still had pesticide residues.

According to the FDA, consumers should wash their hands before preparing produce. Then, they should follow these steps when washing the fruit or vegetable:

1. Rinse the fruit or vegetable before peeling or cutting under plain water while gently rubbing the item with your hands
2. Scrub firm produce, like melons and cucumbers, with a clean vegetable brush
3. Use a clean paper towel or cloth to dry the fruit or vegetable
4. Cut and remove any bruised or damaged areas on the food and remove the outer leaves on cabbage, Brussels sprouts, or heads of lettuce

The FDA says using soap or produce wash is unnecessary when washing fruits and veggies. After washing, perishable produce should be stored in a refrigerator at or below 40 degrees Fahrenheit to retain freshness and food safety.

The bottom line

In the end, fruit and vegetables are important additions to the daily diet, whether conventionally grown or produced on organic farms. Ultimately, using pesticide calculators or adhering to Dirty Dozen lists is a personal choice and may be worth the effort for people concerned about pesticide residue in produce.

Still, Thorne concludes, "Consumers should be reassured that both production methods yield safe and healthy fruits and vegetables that can be consumed with confidence."