University of Washington School of Public Health
Study Finds Lower Pesticide Levels in People who Eat Organic Produce
While health-conscious individuals understand the benefits of eating fresh fruits and veggies, they may not be aware of the volume of pesticides they could be ingesting with their vitamin C and fiber. A study from the University of Washington School of Public Health is among the first to predict a person’s pesticide exposure based on information about their usual diet.
The study, published in Environmental Health Perspectives, showed that among individuals eating similar amounts of fruits and vegetables, those who reported eating organic produce had significantly lower levels of organophosphate (OP) pesticide exposures than those consuming conventionally grown produce.
"For most Americans, diet is the primary source of OP pesticide exposure," said lead author Dr. Cynthia Curl, who conducted her research while a PhD student at the School of Public Health's Department of Environmental and Occupational Health Sciences. "The study suggests that by eating organically grown versions of those foods highest in pesticide residues, we can make a measurable difference in the levels of pesticides in our bodies." Dr. Curl is now an assistant professor at Boise State University's School of Allied Health Sciences.
She and her colleagues analyzed the dietary exposure of nearly 4,500 people from six U.S. cities to organophosphates, the most common insecticides used on conventionally grown produce in the United States. This study included dietary data collected from participants in the Multi-Ethnic Study of Atherosclerosis, a large, multi-institutional project funded by the National Heart, Lung and Blood Institute that is investigating factors that influence the onset of cardiovascular disease.
The researchers predicted each participant's exposure to OP pesticides based on the amount and type of produce each participant typically ate and the U.S. Department of Agriculture's measurements of pesticide residue levels on those foods. The researchers then compared these predictions to pesticide metabolite levels measured in urine samples from a subset of 720 people.
"If we can predict pesticide exposure using dietary questionnaire data, then we may be able to understand the potential health effects of dietary exposure to pesticides without having to collect biological samples from people," Curl said. "That will allow research on organic food to be both less expensive and less invasive."