Daily News Archive
From January 6, 2006                                                                                                        

New Study Revisits Effects of Pesticides on Neurodevelopment
(Beyond Pesticides, January 6, 2006) Published this month in the peer-reviewed scientific journal, Environmental Health Perspectives, is an article called, A Case for Revisiting the Safety of Pesticides: A Closer Look at Neurodevelopment,” on the potential impacts of pesticides on fetal brain development, or neurodevelopment system.

The author, Theo Colborn, is co-author of the book Our Stolen Future (1996), author of numerous peer-reviewed studies and articles on the disrupting effects of pesticides on the endocrine system and was formerly a member of the EPA’s Endocrine Disruptor Methods Validation Advisory Committee (EDMVAC) as part of its EPA Endocrine Disruptor Screen Program. Today, Ms. Colborn runs the The Endocrine Disruption Exchange (TEDX, Inc.) alongside other scientists.

“The quality and quantity of the data about the risk posed to humans by individual pesticides vary considerably. Unlike obvious birth defects, most developmental effects cannot be seen at birth or even later in life. Instead, brain and nervous system disturbances are expressed in terms of how an individual behaves and functions, which can vary considerably from birth through adulthood.

In this article I challenge the protective value of current pesticide risk assessment strategies in light of the vast numbers of pesticides on the market and the vast number of possible target tissues and end points that often differ depending upon timing of exposure. Using the insecticide chlorpyrifos as a model, I reinforce the need for a new approach to determine the safety of all pesticide classes. Because of the uncertainty that will continue to exist about the safety of pesticides, it is apparent that a new regulatory approach to protect human health is needed,” writes Ms. Colborn.

Among several recommended regulatory changes, Ms. Colborn notes that, “a new regulatory approach is also needed that takes into consideration this vast new knowledge about the neurodevelopmental effects of pesticides, not allowing the uncertainty that accompanies scientific research to serve as an impediment to protective actions.”

On its website, EPA acknowledges that, “A variety of chemicals have been found to disrupt the endocrine systems of animals in laboratory studies, and compelling evidence shows that endocrine systems of certain fish and wildlife have been affected by chemical contaminants, resulting in developmental and reproductive problems.

Reported increases in incidences of certain cancers (breast, testes, prostate) may also be related to endocrine disruption. Because the endocrine system plays a critical role in normal growth, development, and reproduction, even small disturbances in endocrine function may have profound and lasting effects.”

Despite being mandated by Congress in 1996 under the Food Quality Protection Act (FQPA) to review pesticides for their potential to disrupt the endocrine system, the EPA is still trying to determine the proper assessment protocol.

"Because of the complexity of the endocrine system and the speed at which governments operate, we will be lucky if we have one crude assay ready for use in the next 5 years," said Theo Colborn in regards to the EPA’s dismissal of peer-reviewed studies showing endocrine effects in frogs from the herbicide atrazine.

TAKE ACTION: Any person interested in the potential effects of pesticides on the endocrine system in humans and wildlife should read this review and other works by Theo Colborn, PhD (additional works can be found at EHP by searching 'Colborn' by author in the upper right corner). Also, write EPA Administrator Stephen Johnson ([email protected]) or call 202-564-4700 and insist that EPA immediately start considering endocrine disruptors and weight-of-evidence data in the regulation of pesticides.