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What is chlorpyrifos?

Chlorpyrifos is a chlorinated organophosphate insecticide, acaricide (miticide). It is used to control cutworms, corn rootworms, cockroaches, grubs, flea beetles, flies, termites, fire ants, mosquitoes, and lice. It is used as an insecticide on grain, cotton, fruit, nut and vegetable crops. It is also used on golf courses and as a non-structural wood treatment.

In 2000, the U.S. EPA and Dow AgroSciences agreed to stop the sale of most home uses for chlorpyrifos because of health risks, primarily to children. However millions of pounds continue to be applied annually for commercial uses in the U.S.

Chlorpyrifos in the Critical Windows of Development

TEDX's Critical Windows of Development website tool presents a timeline of how the human body develops in the womb, with animal research showing when low-dose exposure to endocrine disrupting chemicals during development results in altered health outcomes. Chlorpyrifos is one of the chemicals in the Critical Windows of Development timeline. Click here to view the Critical Windows of Development timeline.

An article by Theo Colborn on the need for a new approach to determining the safety of pesticides, using chlorpyrifos as a model.

A case for revisiting the safety of pesticides: A closer look at neurodevelopment (pdf). In Environmental Health Perspectives. 2006; 114(1):10-17.

Abstract: 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.