Occupational exposure to metals and solvents and the risk of motor neuron disease: A case-control study

Previous studies based on recalled occupational histories have implicated metal and solvent exposure in the etiology of motor neuron disease (MND). We have used death certificates held in pension fund archives and linked unbiased historical occupational records to investigate the effects of occupational exposure to metals or solvents on the risk of death from MND in 22 cases and 206 controls from 22,526 past employees of a major UK engineering company. We found no evidence of increased risk of death from MND in individuals who had worked with either metals (adjusted odds ratio = 0.88, 95% CI 0.35-2.22) or solvents (odds ratio = 1.12, 95% CI 0.45-2.78), and no relation between disease risk and either duration or intensity of exposure. We conclude that metal and solvent exposures are unlikely to be involved in the etiology of MND.