DR. Don's Research Updates
November 22, 2002: Pesticide residues in children eating conventional foods found to be 9 times higher than in organic kids

By Don Lotter, Ph.D., Rodale Institute

Editor's NOTE

In addition to analyzing data from our research trials and developing new domestic and international research initiatives, Don reviews dozens of research studies each week. He'll present the most interesting of his findings every week on the web site.

We all know the obvious – that if you eat organic foods you’ll ingest fewer pesticides than if you eat conventional foods. Scientists however, are trained to call into question the obvious if it hasn’t been shown in research – and some of them are especially diligent at doing this when it supports a big money interest, like the agrichemical industry.

Therefore, a recurring point that has come from scientists is that it has never been shown that children, who are especially vulnerable to pesticides, who consume conventional foods have significantly higher levels of pesticides residues in their bodies than organic food eating children. Another recurring point is that the levels of these chemicals normally found in our bodies do not significantly affect us.

Well, the evidence is beginning to mount on both of these points against the use of chemicals, with two recent studies published in Environmental Health Perspectives, a peer-reviewed scientific journal (peer-review is the sine qua non of scientific publishing).

In the first study researchers interviewed parents entering two Seattle grocery stores, one store specializing in organic and the other mainstream foods. The researchers also visited the homes of the participants and had them keep “food diaries”. The researchers made sure that pesticide use in the homes was not a factor, as well as that the genders, ages, social status, and activities of the two groups were close enough to allow comparison.

Urine samples were analyzed for an organophosphate pesticide residue, dialkylphosphate (DMTP). DMTP was found in 87% of the children. The conventional kids averaged 0.34 micromoles and the organic kids 0.04 micromoles DMTP, a statistically highly significant difference. The researchers determined that the pesticides oxydemeton-methyl, azinphosmethyl, phosmet and malathion were the most likely sources of the DMTP contamination. All of used on produce such as vegetables and fruits.

Another study, by scientists from Erasmus University, Rotterdam in The Netherlands, shows that “normal” levels of industrial and agricultural chemicals at the prenatal stage in the mothers of children significantly affect the childrens’ behavior compared with mothers with low levels of the chemicals.

Girls exposed to higher levels of polychlorinated biphenyls (PCBs) as fetuses were more likely to engage in masculine play in behavioral studies, while boys exposed to similar levels of PCBs engaged in more feminine play. Higher levels of prenatal dioxin were associated with more feminine play in both boys and girls. Just as significant is the fact that the mothers of the children with higher levels of PCBs and dioxins acquired the chemicals via routine dietary and lifestyle habits – in other words they were not clustered around chemical plants or exposed via particular work environments.

Organophosphorus pesticide exposure of urban and suburban pre-school children with organic and conventional diets. Environmental Health Perspectives. 2003. C.L. Curl, et al. [Online 31 October 2002]

Effects of Perinatal Exposure to PCBs and Dioxins on Play Behavior in Dutch Children at School Age. Environmental Health Perspectives. Volume 110, Number 10, October 2002 .H.J.I. Vreugdenhil, et al.