[Select parameters of renal function in smokers in correlation with the exposure to cadmium].

Cigarette smoke contains about 4000 chemical substances, including toxic metals such as cadmium. Smoking of 20 cigarettes a day results in inhalation an average 3.6-6.0 microg of cadmium. Due to nephrotoxic action of some components of tobacco smoke, and especially cadmium, the present study was aimed to evaluate of chosen parameters of kidney status in cigarette smokers in connection with estimation of cadmium concentration. The study was conducted in eighty-nine health and unexposed occupationally to cadmium inhabitants of Bialystok, smoking and non-smoking men and women at age 35-50. The smokers consumed 20 and more cigarettes per day for longer period than 10 years. Blood and morning urine were collected for analysis. In the urine samples, cadmium concentration (by atomic absorption spectrometry) and cotinine concentration (by gas chromatography with mass spectrometry), as an indicator of exposure to cigarette smoke, were determined. The kidney status was evaluated based on the urinary activities of lysosomal enzyme N-acetyl-beta-D-glucosaminidase (NAG) and its isoenzyme B (by colourimetrical method modified by Zwierz et al.) and concentrations of creatinine and urea in the serum (using diagnostic laboratory tests by POCh). The percentage reabsorption of phosphates was evaluated as well (TRP). Cadmium concentration in the urine of smoking women and men was higher compared to non-smokers, but there was no correlation between cadmium and cotinine concentrations in urine. In the smoking women, the urinary activity of NAG and TRP were higher than in non-smoking ones. In smokers, the activities of NAG and NAG-B in men and the activity of NAG-B in women were in the range of values noted in non-smokers, however the frequency of appearance of NAG and NAG-B activities above the limit of detection was higher compared to non-smokers. Cigarette smoking had no influence on the serum concentrations of creatinine and urea in both men and women and TRP in men. The results of the analysis of the urinary NAG and NAG-B activities in conjunction with the frequency of their appearance allow concluding that cigarette smoke might lead to an occurrence of early changes in proximal tubules of men and women.