Parkinsonism and Metal Exposures Among Welders
Harvey Checkoway, Director
Parkinsonism is a debilitating, incurable neurodegenerative disorder that affects over several million people in the US. Parkinson's disease is the main type of PS. Parkinsonism is one of the movement disorders whose primary clinical features are slowed movement, difficulty walking and standing, tremor at rest, and muscle rigidity. Metals present in welding fumes have been related to risks for parkinsonism in some previous studies, although there remains some controversy. Of particular concern are exposures to manganese (Mn), although co-occurring metals, notably iron, lead, copper, chromium, and aluminum, may act independently or synergistically to cause signs and symptoms of parkinsonism. This study is being conducted among a group of approximately 1000 professional shipyard welders. The objective of the project is to determine whether the welders' exposure to Mn and other metals increase their risk for parkinsonism. We will also determine whether welding metals is related to the severity and progression of parkinsonism. The study should ultimately provide valuable new scientific information that will shed light on the causes of parkinsonsim and, ideally, lead to the prevention of this disorder.