Study of welders links manganese fume exposure to Parkinson’s-like symptoms

St. Louis – Prolonged exposure to fumes from the chemical element manganese may put welders at risk for developing symptoms similar to Parkinson’s disease, according to a recent study from the Washington University School of Medicine.

Neurologists specializing in movement disorders examined 886 workers at two shipyards and a heavy machinery fabrication shop, then followed up with 398 of them for up to 10 years to test for Parkinson’s symptoms. They determined that 135 of the workers developed “parkinsonism,” a general term for a group of disorders similar to those associated with Parkinson’s disease.

Cumulative manganese exposure among workers resulted in slowness of movement in the arms and hands, stiffness in the arms and legs, problems with speech, and a reduction in facial expression. Workers who performed flux core arc welding in confined spaces were particularly vulnerable, the neurologists noted.

“These welders are developing [Parkinson’s disease-like] symptoms even though their exposure to manganese is below the current regulatory limits,” study author Brad A. Racette said in a press release. “This study suggests that we need more stringent workplace monitoring of manganese exposure, greater use of protective equipment and monitoring and systematic assessment of workers to prevent this disabling disease.”

The study was published online Dec. 28 in the journal Neurology.