The exposure to cadmium, lead and mercury from smoking and its impact on renal integrity.

TLDR: Smokers are exposed to Cd and Pb, but this exposure is not high enough to produce nephrotoxicity, however, it may incite signs of neph rotoxicity in the presence of risk factors for kidney diseases.

Abstract: Background Human beings are exposed to cadmium (Cd), lead (Pb) and mercury (Hg) from cigarette smoking. Whether this exposure is associated with nephrotoxicity is unknown. Material/methods A total of 68 adult males were included in this study. The studied population was grouped into those who are smokers (n=35) and those who had never smoked (n=33). Cd, Pb and Hg were determined in the blood, urine, hair and nails to assess the extent of exposure to these metals. Urinary excretion of b2-microglobulin (b2M), N-acetyl-b-D-glucosaminidase (NAG), g-glutamyltransferase (g-GT) and alkaline phosphatase (ALP) were determined as markers of tubular damage. Albuminuria was determined as a marker of glomerular damage. Serum levels of creatinine, b2M, and blood urea nitrogen (BUN) were determined to assess glomerular filtration. Results The Cd level in blood and Pb levels in blood and hair were significantly higher in the smokers than non-smokers. Blood levels of Cd and Pb correlated significantly with the smoking index (an indicator for the degree of smoking) in the smokers group. The studied markers of kidney damage neither elevated among the smokers nor correlated with the exposure indices of these metals. Conclusions Smokers are exposed to Cd and Pb. This exposure is not high enough to produce nephrotoxicity. However, it may incite signs of nephrotoxicity in the presence of risk factors for kidney diseases.