Could Lead Exposure Cause ADHD?

A link between blood lead and ADHD symptoms is explained in this new study.

Genes may account for as much as 70 percent of ADHD hyperactivity and inattention in children -- the other unexplained 30 percent could be linked to lead exposure, according to a new study cited in a press release from the Association for Psychological Science (APS).

The Environmental Protection Agency explains that . According to the EPA children under the age of six are most at risk for health problems associated with lead exposure including, "behavioral problems and learning disabilities," and even seizures and death. In the February 2010 issue of the Journal Current Directions in Psychological Science psychological scientist Joel Nigg of the Oregon Health & Science University claims that universal low-level exposure to lead could trigger ADHD symptoms.

According to a recent APS press release, two recent studies may support Nigg's belief. The first study, which compared children diagnosed with ADHD to non-ADHD children, found that the children without ADHD had slightly lower levels of lead in their blood. The second study, the APS explains, found a connection between blood lead and parent and teacher ratings of the child's ADHD symptoms, including hyperactivity and attention problems.

In the APS press release Nigg explains that lead affects brain activity and cognitive control, which can contribute to hyperactivity.

Visit the EPA's website to learn more about lead exposure and what you can do to reduce your risk of lead-related health threats.

Source: Association for Psychological Science