Clinical Briefs: Green Without a Sheen? Organics and Children
With Comments from Russell H. Greenfield, MD Dr. Greenfield is Medical Director, Carolinas Integrative Health, Carolinas HealthCare System, Charlotte, NC, and Clinical Assistant Professor, School of Medicine, University of North Carolina, Chapel Hill, NC.
Source: Lu C, et al. Organic diets significantly lower children's dietary exposure to organophosphorous pesticides. Environment Health Perspect doi:10.1289/ehp.8418, available at: http://dx.doi.org/ [on-line 1 Sept 2005].
Goal: To determine the contribution of daily dietary organophosphorous (OP) pesticide to overall OP pesticide exposure in elementary school-aged children.
Study design: Longitudinal dietary intervention trial over 15 days.
Subjects: Children (n = 23) in the Seattle area aged 3-11 years recruited from public and Montessori schools who partook of conventional diets.
Methods: A letter describing the study was sent home from school with children, and families interested in participating in the trial contacted the research group directly. After further screening, a questionnaire was administered addressing household pesticide use. Children were then enrolled in a 15-consecutive-day sampling period consisting of three phases: conventional diets on days 1-3; organic food items (purchased by research staff from a single grocery store) substituted for most of the children's conventional diet on days 4-8 (parents instructed to exactly replace the items their children would normally have eaten with organics); conventional diets on days 9-15. Parents obtained urine samples from first and last voids of the day, upon which pesticide metabolite analysis was performed.
Results: Frequency of detection of OP pesticide residues differed between initial and terminal conventional diet phases, and markedly between conventional and organic diet phases. All children had pesticide residues detectable at enrollment, but immediately after introduction of the organic diet phase pesticide residues became nondetectable, and remained in that range until re-introduction of conventional food on day 9.
Conclusion: Dietary intake of pesticides represents a major source of exposure for infants and children. An organic diet provides a dramatic and immediate protective effect against exposure to commonly used OP pesticides.
Study strengths: Organic produce was analyzed for pesticide residue through the USDA Pesticide Data Program; trial runs of organic foods offered to children in the same age range to ensure acceptance of taste and appearance; as much as was possible, focus was on organic food as opposed to altering the children's diet.
Study weaknesses: Small sample size; environmental sampling might have provided more intriguing data than a questionnaire on household pesticide use; significant variability in urinary OP metabolite measures; no health outcome data; non-generalizability.
Of note: The study was supported by the U.S. Environmental Protection Agency (EPA); a 1993 report by the National Research Council reported that dietary intake represented the major source of pesticide exposure to infants and children, and may account for the increased pesticide-related health risks noted in children compared with adults; results for pyrethroid pesticides will be published at a later date; organic foods that were substituted for conventional items included fruits and vegetables, wheat- or corn-based products (including popcorn and chips), and juices, all of which are routinely reported to contain OP pesticides; no OP or other pesticide residue was detected in any of the organic food products; two of the metabolites detected were MDA (a metabolite of malathion) and TCPY (a metabolite of chlorpyrifos), representing the common application of these two pesticides on wheat, fruits, and vegetables.
We knew that: OP pesticides are known to cause neurological effects in both animals and humans; there exists a lack of data with which to assess the true nature of pesticide-related health risks in children; the presence of OP pesticide metabolites in the environment as well as food complicates assessment of pesticide absorption; regulatory changes have been instituted since 1998 to lessen household OP pesticide exposure, but fewer agricultural restrictions exist.
Comments: This study suggests that simply by substituting organic food items for conventional ones, parents can minimize exposure to chemicals known to cause untoward neurological effects. A voluntary study involving 23 children who regularly consume fruits, vegetables, and wheat may not be generalizable, and begs corroboration by a larger trial, but the reverberations are both real and complicated. Although few can afford to eat organic produce on a consistent basis, some could afford to lean organic for the fruits and vegetables enjoyed most often by their children, and thus avoid concentrated negative effects from repeated exposure. However, it would be inadequate, if not immoral, for practitioners to recommend organic food items solely to select families with ready access to them should future data continue to point out potential health benefits. We practitioners will be obligated to demand policy change ensuring that all children have access to such nourishment in their schools, and that lower cost organic options be available to the majority of America's families. If the data bear out, as stewards of community health, we can do no less.
What to do with this article: Keep a hard copy in your file cabinet.
SOURCE-Alternative Medicine Alert
