Study: No measurable consumer health benefit for following Dirty Dozen list - The Packer

Study: No measurable consumer health benefit for following Dirty Dozen list

06/15/2011 03:17:00 PM
Tom Karst

 To more accurately assess the potential health impacts from consumer exposure to pesticide residues from the “Dirty Dozen” commodities, this study utilized a probabilistic modeling approach to estimate exposures. The exposure estimates were then compared with toxicological endpoints to determine the health significance of such exposures.

 I encourage readers to consider the full report. What were the results of the study? The authors say this:

 The methodology used to create the “Dirty Dozen” list does not appear to follow any established scientific procedures. Only one of the six indicators used by the EWG crudely considers the amount of pesticide residue detected on the various commodities, and that indicator fails to relate exposures to such residues with established health criteria. Another indicator considers the percentage of samples found to be positive for pesticide residues. The remaining four indicators seem related as all appear to focus upon the existence of residues of multiple pesticides (percent of samples with two or more pesticides, average number of pesticides found on a single sample, maximum number of pesticides found on a single sample, and total number of pesticides found on the commodity) which suggests that the commodity rankings are significantly skewed to reflect instances of multiple residues. While research has demonstrated that the toxicity of a single chemical may be modulated by the presence of another chemical, such effects still require exposure to the modulating chemical to be at a level high enough (above a threshold dose) to cause a biological effect. Results from this study strongly suggest that consumer exposures to the ten most common pesticides found on the “Dirty Dozen” commodities are several orders of magnitude below levels required to cause any biological effect. As a result, the potential for synergistic effects resulting from pesticide combinations is negligible, and the EWG methodology which skews rankings due to the presence of multiple residues is not justified. The EWG methodology also does not appear to be capable of justifying the claim that “consumers can lower their pesticide consumption by nearly four-fifths by avoiding conventionally grown varieties of the 12 most contaminated fruits and vegetables” since no effort to quantify consumer exposure was made.

It should also be mentioned that consumption of organic produce should not be equated with consumption of pesticide-free produce. Winter and Davis [8] summarized pesticide monitoring results from the PDP, the California Department of Pesticide Regulation, the Consumers Union, and a study in Belgium. While conventional produce was between 2.9 and 4.8 times more likely to contain detectable pesticide residues than organic produce, samples of organic produce frequently contained residues. The PDP data, in fact, indicated that 23 percent of organic food samples tested positive for pesticide residues.

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Alex Formuzis    
Washington, DC  |  October, 24, 2011 at 01:54 PM

Leading Scientists Rely on and Back EWG’s Shopper’s Guide to Pesticides By Sonya Lunder and Alex Formuzis A central theme of today’s Food Day is to work toward a more sustainable, healthy, less chemical-intensive food and farm system in the U.S. The Environmental Working Group shares this goal and thought it important for those concerned about the presence of toxic chemicals in food that nationally-recognized public health experts have endorsed EWG’s approach to creating its popular Shopper’s Guide to Pesticides in Produce. Chensheng (Alex) Lu, Associate Professor of Environmental Exposure Biology at Harvard School of Public Health has advised parents and caregivers to use the Shopper’s Guide to “keep nutritional foods in their children’s diets but avoid the intake of pesticide residues in the high-pesticide-risk items.” Lu’s comments came in a study published in the federally-funded journal Environmental Health Perspectives, that found that about half of the foods most frequently eaten by children were on EWG’s Dirty Dozen list. Full post here:

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