A team of scientists from the University of Montreal and Harvard University has discovered that exposure to organophosphate pesticides may be associated with increased risk of Attention-Deficit Hyperactivity Disorder (ADHD) in children.

Published in the journal Pediatrics, the investigation found a connection between exposure pesticides and the presence of symptoms of ADHD. The study focused on 1,139 children from the general U.S. population and measured pesticide levels in their urine.

The authors conclude that exposure to organophosphate pesticides, at levels common among U.S. children, may contribute to a diagnosis of ADHD.

"Previous studies have shown that exposure to some organophosphate compounds cause hyperactivity and cognitive deficits in animals," says lead author Maryse F. Bouchard of the University of Montreal Department of Environmental and Occupational Health and the Sainte-Justine Hospital Research Center. "Our study found that exposure to organophosphates in developing children might have effects on neural systems and could contribute to ADHD behaviors, such as inattention, hyperactivity, and impulsivity."

This study was supported by the Canadian Institutes for Health Research and the National Institute of Environmental Health Sciences.

The study was authored by Maryse F. Bouchard of the University of Montreal and Harvard University, David C. Bellinger, Robert O. Wright, and Marc G. Weisskopf of Harvard University.