Occupational lead exposure in gasoline station forecourt attendants and other occupations in relation to ALS (amyotrophic lateral sclerosis) risk

Amyotrophic lateral sclerosis (ALS) is an always fatal neurodegenerative disease characterised by a gradual death of motor neurons in the spinal cord and brain. The cause of ALS is unknown. There appears to be both a genetic and an environmental aspect of ALS disease causation. Multiple occupations are associated with an elevated ALS risk. Interestingly, many of these occupations involve exposure to lead, indicating a possible connection between ALS and lead exposure. Examples include mechanical workers, military service occupations, leather workers and tanners. Gasoline station forecourt attendants, also known as petrol station assistants, show a severely increased ALS risk, and our measurements on forecourt attendants in South Africa show that they display significantly elevated blood lead concentrations. Thus, forecourt attendants can be added to the list of occupations with overlapping risks for lead exposure and ALS incidence. These occupational risks for forecourt attendants are expected to decrease in the future, as leaded gasoline is being phased out worldwide. Nonetheless, the overlapping risks for ALS incidence and lead exposure among forecourt attendants and several other occupations strengthen the hypothesis that lead exposure contributes to ALS.