Pediatrics
Warn of Neurological Effects of Pesticides on Children
(Beyond Pesticides, April 22, 2004) In this month's
issue of Pediatrics, a peer-reviewed medical journal published
by the American Academy
of Pediatrics, an
article draws attention to the debate over whether low-dose exposure
to pesticides pose a hazard to the health and development of infants
and children and calls on pediatricians to better protect children.
The authors, Bernard Weiss, PhD, Professor of Environmental Medicine and Pediatrics at the University of Rochester School of Medicine and Dentistry in New York; Sherlita Amler, MD; and Robert W. Amler, MD, also point out the essential need to study whether there are subtle neurologic effects that may result from low-level pesticide exposures in individual patients.
In building their case for the dire need for studies on the effects of low-level exposure, the authors dive into the particulars that make children more vulnerable to pesticides than the average adult. In doing so, they highlight the primary routes of pesticide exposure for children, including environmental pathways, dietary exposures and developmental vulnerabilities.
Environmental exposure includes outdoor play activities, and hand contact with soil, lawns, and contaminated objects. The article draws on studies of chlorpyrifos, a chemical still sprayed broadly for mosquito control in urban and rural communities, to illustrate the way children can easily surpass the Environmental Protection Agency’s (EPA) “safe” exposure limits, or reference dose.
Other routes special to children cited include dietary exposures to pesticides, through breastmilk and proportional consumption of foods in low varieties, and differing effects of pesticides due to overall body burdens, body mass levels, and reduced abilities to metabolize toxicants often resulting in greater toxic effects of pesticides.
The authors argue that, "The fetal and neonatal brain are more sensitive than the adult brain to at least some classes of organophosphates; levels presumed to be nontoxic in adults may not be adequately protective of developing organisms."
Despite the rather well-known vulnerabilities of children to pesticide effects, and despite the requirement of the EPA to reassess pesticides based on higher tolerance levels for children under the Food Quality Protection Act (FQPA), according to the authors, "Evidence of subacute and chronic adverse health effects of pesticides in children is shallow despite the considerable extent of exposure and in contrast to the weight of evidence on developmental toxicity of lead and methylmercury. The experimental and epidemiologic evidence is surprisingly sparse given the immense amount of data available about mechanisms of pesticide toxicity, in particular neurotransmitter metabolism and electrophysiologic actions."
The article explains that, "The blood-brain barrier of infants is immature and ‘leaky,’ allowing increased concentration of some chemicals to accumulate in the brain. Exposure to toxicants during these times of rapid cell growth when the blood-brain barrier is immature may disrupt essential elements of development." As an example, the authors point to several studies that show impacts of endocrine disruptors that, during critical windows of development, have resulted in permanent damage and reproductive dysfunction.
Although the EPA has extensive endocrine-related pesticide data and is slowly supposed to be "screening" chemicals (see Daily News), the agency claims that there "is not enough scientific data on most of the estimated 87,000 chemicals in commerce" to do a real evaluation of all the potential endocrine-related risks.
The authors conclude that pediatricians have a distinct role to play in recognizing and appropriately treating acute symptoms of pesticide exposure. They advise pediatric clinicians to first become familiar with and educated on identifying acute pesticide poisonings. In one example the article illustrates how clinicians misdiagnosed and mistreated organophosphate poisoning-related complaints (reactive airway disease, seizures, intractable vomiting, or diarrhea) without ever considering pesticide exposure as an underlying cause. Secondly, the authors advise clinicians to actively “prevent exposure of infants and children to pesticides” by encouraging parents to be prudent when using pesticides in the home and adjacent areas.
For an electronic version of the article, please contact Beyond Pesticides.
TAKE ACTION: Instead of encouraging parents to prudently use pesticides, Beyond Pesticides offers parents and communities a plethora of non-toxic alternatives to pesticides. Learn how you can protect your children and loved ones from the effects of pesticides in your home, on your lawns, in schools and other public places. See Beyond Pesticides Alternative Fact Sheets, How-To Factsheets, information on Integrated Pest Management (IPM) in schools and any of our other available materials and publications.