Manganese Poisoning and Exposure in Pennsylvania

Abstract

Manganese exposure was studied in 75 Pennsylvania industrial plants. In 12 plants exposures were In excess of the threshold limit value (TLV). During the course of the survey, seven cases of manganese poisoning and 15 others believed to be borderline cases came to our attention. Two cases contracted the exposure from crushing and bagging of manganese ore, two from exposure to ferromanganese alloy dust, two from manganese dioxide fume produced in casting, and one from arc burning of manganese steel. Problems encountered In the diagnosis of manganese poisoning are discussed and the importance of obtaining a thorough occupational history is stressed.