It is frequently alleged that manganese poisoning leads to or accelerates progressive Parkinson’s disease (PD). Some cases have succeeded in a lower court in the USA but overturned on appeal. This may not always be the case. There is increasing recognition of overlap between the PD mechanism and the mechanism of reversible Parkinsonism. Reversible manganese poisoning has been a recognised outcome since before the 1960s, leading to some exposure control interventions.
Parkinson’s disease affects 2% of the over 60’s. If welding-related manganese exposure is accepted the number of speculative claims could be considerable. Exposure to welding fume was not well controlled until recently and is still not well controlled globally.
Reserving for welding-related Parkinson’s disease is difficult to assess. A probabilistic approach may provide the best fit to insurance risk management procedures.
Epidemiological and laboratory evidence continues to accumulate. We assess this and how it might change the parameters in a probabilistic calculation.