Effects of Mercury Vapour Exposure at Low Concentrations on Urinary Activity of N‐Acetyl‐Beta‐D‐Glucosaminidase

Abstract

Effects of Mercury Vapour Exposure at Low Concentrations on Urinary Activity of N‐Acetyl‐Beta‐D‐Glucosaminidase: Nobuo Ishihara. Research Centre for Occupational Disease, Tohoku Rosai Hospital—Effects of exposure to mercury vapour less than 0.02 mg Hg/m3 on urinary N‐Acetyl‐beta‐D‐glucosaminidase (NAG) activity were studied in seven Japanese workers from 1991 to 1997. According to the record of periodical medical examinations they have been engaged in mercury work since 1987 at the latest. Mercury concentrations in urine, plasma, erythrocytes, and hair and the urinary protein concentration did not change significantly during the course of the study. Urinary NAG activity, however, increased significantly in 1996 notwithstanding the absence of the significant correlations between NAG activity and mercury concentrations in urine and plasma, and the increased NAG level was maintained up to 1997. All of the present subjects were less than 57 years old in 1997. The effect of aging on urinary NAG activity was therefore excluded, and the increase in urinary NAG activity should be due to the occupational mercury vapour exposure. As in the case of mercury concentrations in blood, urinary NAG activity also should be one of the useful indicators of renal effects of mercury so long as data for before work and/ or just after the start of mercury work are available.