(Beyond Pesticides, January 31, 2008) A study to be published in the February 2008 issue of Environmental Health Perspectives finds that children who eat a conventional diet of food produced with chemical-intensive practices carry residues of organophosate pesticides that are reduced or eliminated when they switch to an organic diet. The study is entitled “Dietary Intake and Its Contribution to Longitudinal Organophosphorus Pesticide Exposure in Urban/Suburban Children” (Chensheng Lu, Dana B. Barr, Melanie A. Pearson, and Lance A. Waller) and includes authors from Rollins School of Public Health, Emory University, and the National Center for Environmental Health, Centers for Disease Control and Prevention.According to the authors, â€śThe objective of this article is to present the data of assessing young urban/suburban childrenâ€™s longitudinal exposure to OP [organophosphate] pesticides in a group [of] young children participating in the Children Pesticide Exposure Study (CPES). The results from this study identify not only the predominant source of OP pesticide exposure but also the profile of exposures in children that are vital in formulating the strategies, both from the regulatory policy and personal behavior change perspectives, in reducing childrenâ€™s exposures to OP pesticides.â€ť
The study design included 23 children, male and female, from the Seattle area, ages 3-11 years who only consumed conventional diets and were recruited for a one-year study conducted in 2003-2004. Of the 23, 19 completed the study. Children switched to organic diets for five consecutive days in the summer and fall sampling seasons. The authors measured specific urinary metabolites for malathion, chlorpyrifos and other OP pesticides in urine samples collected twice daily for a period of 7, 12, or 15 consecutive days during each of the four seasons. According to the authors, â€śBy substituting organic fresh fruits and vegetables for corresponding conventional food items, the median urinary metabolite concentrations were reduced to non-detected or close to non-detected levels for malathion and chlorpyrifos at the end of 5-day organic diet intervention period in both summer and fall seasons. We also observed a seasonal effect on the OP urinary metabolite concentrations, and this seasonality is correspondent to the consumption of fresh produce throughout the year.â€ť And, â€śConsidering the lack of residential use of OP pesticides among the families of CPES-WA children, consumption of conventional diets is likely to be the sole contributing factor to the seasonality effect of pesticide exposures.â€ť
The authors point out that few studies evaluate the longitudinal exposure to pesticides that all children experience. According to the authors, â€śMost of the studies published in the literature have either targeted children living in agricultural environments or have used a cross-sectional design with spot sample collection.â€ť
The authors raise concerns about inadequate attention being given by regulators to chronic low-level exposures to pesticides, such as those found in their study. They point out that, â€śUsing spot biomarkers [one-time measurement of urinary metabolites] of OP pesticide exposure to examine the link between adverse health outcomes and cumulative OP pesticide exposure is obviously an inadequate approach.â€ť
Corresponding author: Chensheng Lu, Department of Environmental and Occupational Health, Rollins School of Public Health, Emory University, 1518 Clifton Road, NE, Atlanta, GA 30322, (404)727-2131, (404)727-8744 (fax), [email protected].