Exposure to neurotoxic metals among workers in Singapore: an overview

The extent of occupational exposure to inorganic lead, manganese, arsenic and inorganic mercury in Singapore was determined from the results of Statutory Medical Examinations and environmental monitoring carried out by the Department of Industrial Health in 1989. There were 786 workers exposed to lead. Of these, 7.8 per cent had blood levels greater than 40 micrograms/dl. There were 67 workers exposed to mercury, 11.9 per cent of whom had urinary mercury levels greater than 50 micrograms/l. There were 101 and 144 workers exposed to arsenic and manganese respectively. None of the biological samples exceeded the health-based limits. A review of local studies showed that some of the exposed workers had neurophysiological and neurobehavioural changes.