A new research conducted at the Cincinnati Children's Hospital Medical Center suggests that children's exposure to tobacco smoke while still in the mother's womb and lead during childhood can significantly raise the risk of Attention-deficit hyperactivity disorder (ADHD).
"Tobacco and lead exposure each have their own important adverse effect...But if children are exposed to both lead and prenatal tobacco, the combined effect is synergistic," lead author, Tanya Froehlich, a physician in the Division of Developmental and Behavioral Pediatrics at Cincinnati Children's said.
Robert Kahn, a physician and researcher at Cincinnati Children's and the study's senior author said: "Although we tend to focus on ADHD treatment rather than prevention, our study suggests that reducing exposures to environmental toxicants might be an important way to lower rates of ADHD."
Researchers reviewed the cases of 3,907 children aged 8 to 15, gathered between 2001 and 2004 from the National Health and Nutrition Examination Survey (NHANES) from the National Center for Health Statistics at the Centers for Disease Control and Prevention, to come up with their findings.
They concluded that children prenatally exposed to tobacco smoke were 2.4 times more likely to suffer from ADHD.
Children with blood lead levels in the top third had a 2.3times more chance of ADHD.
And those children who had had exposure to both lead and tobacco had almost 8 times higher possibility of ADHD than unexposed kids.
Maternal reports of cigarette use were used to measure the child's prenatal exposure to tobacco, while current blood lead level was used for gauging the lead exposure.
The study will appear online in Pediatrics.