Manganism, Parkinson’s disease and welders’ occupational exposure to manganese – Part 1: Sources of manganese exposure and its role and function in human health and disease

It has been asserted that employment as a welder is associated with an excess risk for the neurological disorder of manganism and development of Parkinson’s disease at an earlier than usual age. It has been suggested that this may be due to absorption of manganese in emissions from welding processes. In this two part paper sources of exposure to manganese, its role in human health and its toxicological potential are considered then, in Part 2, published reports on the incidence of manganism and Parkinson’s disease in welders and of a possible causal link between this and occupational exposure to manganese compounds are reviewed critically and evidence-based conclusions are drawn.