Lead Contributes to Depression

Thursday, December 17, 2009 by: Dr. David Jockers
Tags: lead, depression, health news

(NewsTarget) Lead exposure was thought to be a thing of the past, but it is more common today than most realize. A recent study in the Archives of General Psychiatry (December issue) found that individuals with lead levels of 2.11 ug/dL or more had 2.3x greater risk of being diagnosed with Manic Depressive Disorder (MDD) and had nearly 5x the odds of panic disorder compared with those with lead levels of 0.7 ug/dL or less.

The lead author, Maryse F. Bouchard, PhD, Universite de Montreal, Quebec, Canada, and Harvard School of Public Health, noted that, "What is most surprising is the finding that lead can be associated with adverse mental health status at such low levels of exposure." Among nonsmokers (smoking increases lead accumulation), the elevation in risk between the highest & lowest blood lead levels was increased by 2.5x for MDD and 8.2x for panic disorders.

Elevated symptoms of depression, hostility, and anxiety have been shown in a number of studies done on employees from foundries, smelters, and battery plants who had very high blood lead levels (averaging 40 ug/dL). "What is most surprising is the finding that lead can be associated with adverse mental health status at such low levels of exposure," said Dr. Bouchard. The mean blood level in study subjects was 1.61 ug/dL.

Although average blood lead levels are way down, new research shows that even low amounts can be harmful, says Ellen Silbergeld, PhD, a professor of environmental health sciences at Johns Hopkins University. Just 4 ug/dl (micrograms per deciliter) can double your risk of a fatal heart attack or stroke, and similar levels may also cause memory loss, says Eliseo Guallar, MD, PhD, an epidemiologist at Johns Hopkins.

Another study showed higher prevalence of self-reported anxiety, phobic anxiety, and depression was conducted in older men who were nonoccupationally exposed (averaging 6.3 ug/dL). "One of the shocking things is that in my study group, the mean blood lead level was only 1.6 ug/dL, which is representative of the exposure level in the general population," Dr. Bouchard said.

"These findings suggest that lead neurotoxicity may contribute to adverse mental health outcomes, even at levels generally considered to pose low, or no, risk," the researchers conclude. "These findings, combined with recent reports of adverse behavioral outcomes in children with similarly low blood lead levels, should underscore the need for considering ways to further reduce environmental lead exposures," they write.

Steps have been taken over the years to decrease environmental lead. One big step in the right direction was the elimination of lead from gasoline. This process significantly decreased average blood levels in the general population, but remaining sources of exposure include contaminated water, home plumbing fixtures, paints, ceramic dishes, and hunting & fishing gear.

1.Laurie Tarkan. New Places to Look for Lead The childhood danger that's also hurting grown-ups - 7 hidden places lead is lurking. www.prevention.com/newplacestolookforlead/in...

2.Kelly, Janis C. Medscape Medical News: "Safe" Lead Levels Linked to Depression, Panic in Young Adults. Dec 9, 2009.

3.Arch Gen Psychiatry. 2009;66:1313-1319.

4.Wikipedia: http://en.wikipedia.org/wiki/Lead

About the author

Dr. David Jockers owns and operates Exodus Health Center in Kennesaw, Ga. He is a Maximized Living doctor. His expertise is in weight loss, customized nutrition & exercise, & structural corrective chiropractic care. For more information go to www.exodushc.com To find a Maximized Living doctor near you go to www.maximizedliving.com