The Nervous System Effects of Occupational Exposure to Manganese - Measured as Respirable Dust - in a South African Manganese Smelter

These data did not provide empirical support for a respirable, as opposed to an inhalable, dust metric being more sensitive in the identification of Mn effects. Neither metric showed convincing effects within the exposure range studied. Further study is needed to determine a threshold for respirable Mn effects, if such exist, and to verify our findings.