Evaluation of toxic risk assessment of arsenic in male subjects through drinking water in southern Sindh Pakistan.

The arsenic (As) hazardous quotient was estimated based on concentration of As in drinking water and scalp hair of male subjects of two age groups (n=360) consuming As contaminated water at different levels and non-contaminated drinking water. The total As concentrations in drinking water of less-exposed (LE) and high-exposed (HE) areas was found to be 3- to 30-fold higher than the permissible limit of the World Health Organization (2004) for drinking water, while the levels of As in drinking water of non-exposed (NE) areas was within the permissible limit. The levels of As in scalp hair samples of male subjects of two age groups belonging to NE, LE, and HE areas ranged from 0.01 to 0.27, 0.11-1.31, and 0.36-6.80 µg/g, respectively. A significant correlation between As contents of drinking water and As concentration in scalp hair was observed in sub-district Gambit (r=0.825-0.852, p<0.001) as compared to those subjects belonging to LE sub-district Thari Mirwah. A toxicity risk assessment provides a hazard quotient corresponding to <10 that indicates non-carcinogenic exposure risk of understudy areas.