Is lead in your water affecting your mood?

RODALE NEWS, EMMAUS, PA—Feeling down? You may want to have your blood lead levels checked. A new study published in the Archives of General Psychiatry has found higher instances of panic disorders and depression in young adults with lead levels considered "normal."

THE DETAILS: Researchers used data from National Health and Nutrition Examination Survey collected between 1999 and 2004. They selected a sub-sample of adults 20 to 39 years of age who had completed a psychological evaluation in addition to blood lead level testing, and compared the lead levels with clinical diagnoses of major depressive disorder or panic disorder. The total sample included 1,987 adults with an average blood level of 1.24 micrograms/deciliter, which is representative of the levels found in the general population, says study author Maryse Bouchard, PhD, research fellow at the Harvard School of Public Health. They found that the higher one's blood lead level, the higher one's chance of being diagnosed with either major depression or panic disorder. They found similar results even after excluding adults who smoked, a behavior that increases the risk of high lead levels and depression and panic disorders.

WHAT IT MEANS: Having lead in your system, even at a level not considered harmful, can seriously affect your mood and anxiety levels. What was most concerning, says Bouchard, is that the levels they found weren't extreme, but were representative of the population as a whole. "That's absolutely anybody," she says, "and we're seeing an increase in depression and panic disorders."

Lead decreases the levels of two neurotransmitters, dopamine and seratonin in the brain. These two chemicals are involved with cognition (which is why children with lead poisoning often suffer from learning problems), motor skills, and mental health, says Bouchard. Low levels of both seratonin and dopamine triggers depression, and low dopamine levels have been associated with social anxiety and having little remorse about personal behavior, which may explain why other research has found a relationship between criminal behavior in young adults and high blood lead levels when they were children.