The manganese in fumes from welding may cause neurological damage similar to what is found in the brains of people suffering from Parkinson’s disease.
Researchers from the Washington University School of Medicine in St. Louis evaluated brain scans of 20 welders with an average of 30,000 hours of lifetime welding exposure, and compared the findings to scans from 20 Parkinson’s patients and another 20 healthy people who weren’t welders. The study, published in the journal Neurology, showed an increased risk of damage to the same brain area harmed by Parkinson’s.
The welders’ motor skills also were found to be impaired, although not as extensively as those in patients in the early stages of Parkinson’s. The disease is characterized by, among other things, trembling in the hands, arms, legs and face.
The welders who participated in the study had an average 11.7 percent reduction in a marker of the chemical dopamine compared to people who did not weld. Dopamine helps nerve cells communicate and is reduced in specific brain regions in people with Parkinson’s.
The study does not show a specific cause and effect between manganese exposure and dopamine reduction. But according to a report on ohsonline.com, the welders’ average blood manganese levels were found to be two times the upper limits of normal blood manganese levels.
The study’s lead author, Dr. Brian Racette, noted that one million U.S. workers perform welding as part of their jobs. “If a link between neurotoxic effects and these fumes were proven, it would have a substantial public health impact for the U.S. workforce and economy,” he said.
But another expert, Dr. Michael Pourfar, director of the division of movement disorders at North Shore-LIJ Health System in Great Neck, N.Y., told HealthDay News that the exposure to manganese “does not clearly cause the same classic Parkinson’s that most people are familiar with.” He added that “many questions remain about the nature of the association between manganese and parkinsonism.”


