Researchers at the Cincinatti Children's Hospital Medical Center have added to the evidence linking exposure to substances in the womb to Attention Deficit Hyperactivity Disorder (ADHD). They studied 2,588 children aged between eight and fifteen of whom 8.7% had ADHD. Children who had been exposed to high prenatal levels of tobacco were 2.4x more likely to have ADHD while children whose mothers had had high levels of lead in their bloodstream were 2.3x more likely. Children who were exposed to both tobacco and lead were 8.1x more likely to have ADHD.
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