MEASUREMENT OF THE RESPIRATORY BURST AND CHEMOTAXIS IN POLYMORPHONUCLEAR LEUKOCYTES FROM MERCURY-EXPOSED WORKERS

The chemotactic and nitroblue tetrazolium reducing activities of neutr ophils from 48 mercury-exposed workers were examined and compared with those of non-exposed, age- and sex-matched individuals, At the time o f testing, the exposed population had a mean (+/- s.d.) urinary mer cu ry concentration of 24.0 +/- 20.1 mu g g(-1) creatinine and in 44 of t hese workers urinary mercury levels were below the accepted threshold level (TLV) of 50 mu g g(-1) creatinine. The two neutrophil functions were significantly reduced in the mercury-exposed workers compared wit h the controls, In 28 of these workers, chemotaxis was re-evaluated 6 months later, During the intervening 6 months, the level of hygiene wa s improved throughout the plant and urinary mercury concentrations wer e determined monthly in each worker. Despite a significant reduction i n urinary mercury concentrations, neutrophil migration did not return to within the normal range. These results suggest that 'safe' level me rcury exposure may lead to impairment of neutrophil function.