The publication of a new study in Neurology, that contends the long-term effects of airborne manganese from welding may be associated with an increasing appearance of Parkinsonism symptoms in welders and other exposed individuals, may resurrect a species of toxic tort litigation that was thought to be resolved.
As reported in the December 28, 2016 edition of the St. Louis Post-Dispatch, a new study from researchers at Washington University in St. Louis found that the long time effects of manganese fumes on welders increased over time. Dr. Brad A. Rancette, senior author of the study and a neurologist with the Washington University School of Medicine, said that “the more exposure you had the greater the progression of Parkinsonism. Even at the lower levels of exposing we saw progression . . .”
The study, “Does-Dependent Progression of Parkinsonism in Manganese-Exposed Welders”, published in the medical journal Neurology on December 28, 2016 looked at 886 welders at three worksites in the Midwest: two shipyards and a heavy-machinery fabrication shop. Previously it was reported that high levels of manganese from welding fumes and other sources can result in the same neurological problems present in Parkinson’s disease such as slowness, tremors, and difficulty in walking and sleeping. Dr. Rancette stated that his new study suggests that welders, who were exposed to airborne manganese at levels well below the current OSHA maximum threshold, could develop severe neurological problems associated with those exposures.
Welding rod litigation was the subject of thousands of lawsuits in the early 2000’s against various welding rod manufacturers and suppliers. Over the life of the litigation, defendants prevailed in 25 of 30 cases that reached trial, and then subsequently won reversals on 3 of the five plaintiffs’ trial verdicts. Many of those suits were consolidated in 2003 in a Multi-District Litigation proceeding centered in a federal court in Cleveland, Ohio against many of the welding rod manufacturers. Later, the vast majority of claims then pending in a MDL were voluntarily dismissed after allegations of fraud arose.
A previous meta-analysis published in Neurology in September 2012 suggested that there no relationship between the potential of manganese exposure and an increased risk of Parkinson’s disease. The review and meta-analysis also followed earlier published results from a Multi-Center Case-Control Study in an article in the Archives of Neurology.
The current safety standard set by OSHA is a level of 5 milligrams per cubic meter. In 2013, the American Conference of Governmental Industrial Hygienists recommended a limit of 0.02 milligrams of manganese per cubic meter. The Rancette study showed people with an estimated exposure of only 0.14 milligrams per cubic meter of air as having significant neurological signs consistent with Parkinson’s and other neurodegenerative disorders.
Employers and welding product makers should be aware that a new round of civil litigation/workers compensation claims may emerge because of this new reported association between welding rod fumes and Parkinson’s disease. This is in the context of both increased regulation, but also the possibility of a new round of toxic tort litigation brought by an increased class of plaintiffs.