July 14, 2009

Pesticides in blood linked to Parkinson’s

U.S. researchers have linked Parkinson's disease to significantly higher blood levels of a particular pesticide.

The study, published in Archives of Neurology, found higher levels of the pesticide beta-HCH (hexachlorocyclohexane) in 76 percent of people with Parkinson's, compared with 40 percent of healthy controls and 30 percent of those with Alzheimer's.

The study involved 113 participants -- ages 50-89 -- whose blood was tested for 15 pesticides known as organochlorines. Fifty had Parkinson's, 43 were healthy and 20 had Alzheimer's.

Much higher levels of the beta-HCH were in the air, water and food chain when the Parkinson's patients were in their 20s and 30s, senior author Dr. Dwight German of the University of Texas Southwestern Medical Center in Dallas said in a statement. Also, the half-life of the pesticide is seven to eight years, so it stays in the body for a long time.

The study findings might provide the basis for a beta-HCH blood test to identify people at risk for developing Parkinson's disease, German said.

Some people with Parkinson's might have the disease because of exposure to environmental pesticides, but there are also genes known to play a role in the condition, German said.