by Mary Saucier Choate,
M.S., R.D., L.D.
Dietitian and Food and Nutrition Educator
If I were not a Co-op nutritionist, I would just read the Environmental Working Group’s (EWG) list of the dozen top fruits and vegetables to avoid because of pesticide residues and leave it at that. But lucky for me, my job requires that I look deeply into food and nutrition issues for our members and customers, so my report goes way beyond what this one group publishes.
There are many important reasons to support organic agriculture, local foods, and environmentally supportive measures such as integrated pest management, but in this report, I would like to explain why it is not necessary to eat only organic produce for good health.
EWG’s widely disseminated lists of produce to buy organic lead many busy consumers to think that they are really getting a lot of pesticides from certain fruits and vegetables. Recent studies from toxicologists and researchers, however, have shown that this group is not using accurate information or giving the full story.
The way EWG puts it, you would think that toxic amounts of pesticides are frequently found on certain produce items. But in a recent Journal of Toxicology article, Dr. Carl Winter, a well-respected food toxicologist at the University of California, found that all of the pesticide exposure estimates that the EWG reported were well below established safe levels.
How is a safe level set? The Environmental Protection Agency (EPA) builds in many uncertainty factors into the amount of pesticide residue allowed in foods. These uncertainty factors create additional margins of safety(scaling down the amount of pesticide residue allowed by factors of hundreds to thousands). In addition, the 1996 Food Quality Protection Act (FQPA) requires EPA to use an extra ten-fold safety factor, if necessary, to protect infants and children from effects of pesticides.
All of these actions lead to a safe measure of pesticide exposure called the Chronic Reference Dose. This amount of daily oral exposure to pesticide residue is likely to be without an appreciable risk of harmful effects during a lifetime, even to pregnant women, infants, and children.
Winter found that only one of the 120 exposure estimates made in EWG’s report exceeded one percent of the safe exposure level, and only seven exposure estimates exceeded 0.1 percent of the safe level. Three quarters of the pesticide/commodity combinations demonstrated exposure estimates below 0.01 percent of the safe level(corresponding to exposures one million times below chronic No Observable Adverse Effect Levels from animal studies), and 40.8 percent had exposure estimates below 0.001 percent of the safe level.
Winter concluded that exposures to the most commonly detected pesticides on the twelve commodities EWG calls “the Dirty Dozen” pose negligible risks to consumers, and EWG’s advice to substitute organic forms of the twelve commodities for conventional forms does not result in any appreciable reduction of consumer risks. He also stated that the methodology used by EWG group to rank commodities with respect to pesticide risks lacks scientific credibility.
Dr. Robert Krieger, toxicologist and Director of the Personal Chemical Exposure Program at University of California, wrote a comprehensive report: “Perspective on Pesticide Residues in Fruits and Vegetables,” for the Alliance for Food and Farming’s website, safefruitsandveggies.com. The alliance is a group of fruits and vegetable farmers, producers, and their representatives.
In the report, Kreiger gives a detailed explanation of the EWG data and their interpretation of pesticide exposure and explains clearly how they don’t provide important information such as the fact that a child, teen or adult could eat “hundreds to thousands of servings of fruits or vegetables in a single day” to even reach the No Observed Adverse Effect Level (NOAEL) of pesticide. This level is the highest level of a substance which causes no detectable adverse alteration of any health measurement or life span. Kreiger found that this conclusion could accurately be assigned to all of the “dirty” and “clean” produce EWG examined (they looked at 53 different fruits and vegetables).
These studies are not the only place where you can find evidence that conventionally grown produce is not harmful to health. Health organizations such as the American Institute for Cancer Research, the American Cancer Society, the American Heart Association, the American Academy of Pediatrics, and the March of Dimes all recommend a diet with lots of fruits and vegetables, without warning against conventionally grown. This is because in population studies, people with diets rich in conventional fruits and vegetables have the least risk of chronic diseases such as cancer, heart disease, and type 2 diabetes.
If reliable evidence becomes available that current studies are wrong, and that pesticides at the extremely low levels we consume from conventional produce are harmful to health, I will immediately communicate this to the Co-op community. At this time, however, after years of research, the risk from conventional produce consumption on personal health has not been demonstrated.
Some consumers fear that what we don’t know about pesticides can hurt us. For those who feel this way, avoiding conventional produce would be appropriate. To lower pesticide exposure risk even further, everyone should carefully follow directions when applying home insecticides and chemicals on lawns, gardens, and golf courses. Even better, choose non-toxic alternatives. These pesticide exposures carry the largest risk of unacceptably high pesticide exposure if not used carefully and properly.
EWG states: “We recommend that people eat healthy by eating more fruits and vegetables, whether conventional or organic.” If the organization truly believes that pesticide residues on produce are so harmful, it just doesn’t make sense to encourage people to eat more conventional produce. They can’t have it both ways.
Perspective on Pesticide Residues in Fruits and Vegetables
Dietary Exposure to Pesticide Residues from
Commodities Alleged to Contain the Highest
EWG’s Shopper’s Guide to Pesticides
National Pesticide Information Center
Setting Tolerances for Pesticide Residues in Foods
Safe Fruits and Veggies.com