Urinary N  -acetyl-β-glucosaminidase as an indicator of renal dysfunction in electroplating workers

International Archives of Occupational and Environmental Health (Impact Factor: 2.2). 06/1998; 71(5):348-352. DOI: 10.1007/s004200050291

ABSTRACT Objectives: To investigate chromium-induced renal dysfunction in electroplating workers. Methods: A cross-sectional study was used to evaluate four biochemical markers of renal function. A total of 178 workers were divided
into 3 comparable groups consisting of 34 hard-chrome plating workers, 98 nickel-chrome electroplating workers, and 46 aluminum
anode-oxidation workers, who represented the reference group. Ambient and biological monitoring of urinary chromium were performed
to measure exposure concentrations. Results: Overall, urinary chromium concentrations were highest among hard-chrome plating workers (geometric mean 2.44 μg/g creatinine),
followed by nickel-chrome electroplating workers (0.31 μg/g creatinine) and aluminum workers (0.09 μg/g creatinine). Airborne
chromium concentrations were also highest in the hard-chrome plating area (geometric mean 4.20 μg/m3), followed by the nickel-chrome electroplating area (0.58 μg/m3) and the aluminum area (0.43 μg/m3). A positive correlation was found between urinary chromium and airborne concentrations (r = 0.54, P < 0.01). Urinary concentrations of N-acetyl-β-d-glucosaminidase (NAG) were also highest among hard-chrome plating workers (geometric mean 4.9 IU/g creatinine), followed
by nickel-chrome workers (3.4 IU/g creatinine) and aluminum workers (2.9 IU/g creatinine). The prevalence of “elevated” NAG
(>7 IU/g creatinine) was significantly highest among hard-chrome plating workers (23.5%), then among nickel-chrome workers
(7.1%) and aluminum workers (8.7%). Differences in β2-microglobulin, total protein, and microalbumin were not significant. Conclusion: The author's evidence indicates that NAG is an early indicator of renal dysfunction in hard-chrome plating workers.

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