Renal function in miners intermittently exposed to elemental mercury vapour.

The authors investigated renal damage in 45 mercury miners under conditions of relatively short and low-level exposure to elemental (metallic) mercury vapour (Hg0). The analysis included urinary mercury, immunoelectrophoresis of urinary proteins, immunofixation and high-resolution electrophoresis, quantitative analysis of urinary albumin, and urinary alpha 1-microglobulin before and after exposure. The activity of urinary N-acetyl-beta-D-glucosaminidase (NAG) enzyme was determined after exposure. The average duration of exposure of miners was 37 (6-82) days. Urinary mercury significantly increased during exposure. Immunoelectrophoretic changes in the composition of urinary proteins occurred after exposure in 22 of 45 miners, of whom 15 showed high molecular weight (HMW) pattern of urinary proteins and seven showed low molecular weight (LMW) pattern. Only a slight increase in the urinary alpha 1-microglobulin concentration and NAG activity was found in miners with the LMW pattern of urinary proteins. The results point to a slight glomerular and tubular damage in a significant proportion of exposed miners with increased absorption of mercury vapour.