Parkinson's and manganese air pollution link

A University of Toronto study is the first in North America to draw a link between Parkinson's and manganese air pollution, and suggests industry-generated pollutants poses a greater health risk than traffic-generated manganese.

Murray Finkelstein, assistant professor in the department of family and community medicine, worked with Berkeley professor Michael Jerrett to compare the incidence of diagnosis and treatment of Parkinson's with markers of exposure to vehicle exhaust and industrial emissions in the cities of Toronto and Hamilton. The study, which examined a cohort of 110,000 subjects over three years, appears in this month's issue of Environmental Research .

In Toronto, the researchers found no association between Parkinson's diagnosis and exposure to manganese through traffic-generated air pollution. In Hamilton, the odds of a physician diagnosing Parkinson's increased with the amount of ambient manganese in the air. The study was sparked by interest in the effects of methylcyclopentadienyl manganese tricarbonyl (MMT), an agent added to Canadian gasoline for many years to reduce engine knocking.

“The results suggest that the manganese threat posed by traffic-generated pollution may be relatively small, but that exposure to ambient manganese in the air from sources like steel foundries does advance the age of diagnosis of Parkinson's disease,” says Finkelstein. “This study supports the theory that exposure to manganese adds to the natural loss of neurons attributable to the aging process.”