"A.D.H.D. is attention deficit hyperactivity disorder. Government estimates say three to seven percent of school-age children in the United States have it. Adults can also have it. People with A.D.H.D. have problems with paying attention, controlling their behavior and being overly active.

Now, a study has linked an increased risk of A.D.H.D. in children to exposure to some kinds of pesticides. The chemicals are known as organophosphate pesticides. They kill insects by attacking their nervous systems. Earlier studies have shown that some of the compounds cause hyperactivity and thinking deficits in laboratory animals."

Caty Weaver, Jessica Berman, and Steve Ember report for Voice of America May 25, 2010.
[2]
See Also:

"Chemicals May Increase Diabetes Risk, Not Just Genes, Weight and Exercise" (ABC News) [3]