Co-exposure of arsenic and cadmium through drinking water and tobacco smoking: risk assessment on kidney dysfunction.

The combined exposure of arsenic (As) and cadmium (Cd) causes more pronounced renal toxicity. The study aimed to evaluate the level of As and Cd in biological samples (blood and urine) of adults males, age ranged (30-50 years) exposed referent (ER) and exposed kidney patients (EKP), consumed contaminated drinking water of lake and smoking local cigarettes manufactured by tobacco plants grown on agricultural soil, irrigated with contaminated lake water. For comparative purpose age matched nonexoposed referent (NR) and nonexposed kidney patient (NKP), consumed municipal treaded water and smoking branded cigarette were also selected. The As and Cd levels in drinking water, biological samples, tobacco of branded and nonbranded cigarettes were analyzed using electrothermal atomic absorption spectrometry. The As and Cd concentrations in lake water were higher than the permissible limit recommended by the World Health Organization for drinking water. The As and Cd levels in local cigarette tobacco were found to be 3- to 4-folds higher than branded cigarettes. The biochemical parameters especially urinary N-acetyl-β-glucosaminidase (NAG) of ER, EKP, ER, and EKP subjects were studied as a biomarkers of renal dysfunction. The NAG values were found to be higher in EKP as compared to NKP (p < 0.01). The linear regressions showed higher correlations between As and Cd concentrations in water versus blood and urine samples of EKP (r = 0.71-0.78 and 0.68-0.72), as compared to NKP (p < 0.05).