Assessment of Arsenic Contamination in Groundwater and Associated Human Health Risk

Drinking water contamination by arsenic (As) is of significant concern due to its potential cause of cancer and arsenicosis. In this study, out of the 200 samples (n = 200), the mean As concentrations ranged from below detection limit (BDL) to 3.30, 4.81, 4.42 and 3.85 mu g L-1 in small residential, roadside, industrial and household areas, respectively. From 200 total samples, 9% of the groundwater samples showed As levels higher than the WHO safe guideline limit of 10 mu g L-1. Human health risk was assessed using average daily intake (ADD), hazard quotient (HQ) and cancer risk (CR) values which were found to be greater than the recommended values by the United States Environmental Protection Agency (1.0 and 10(-6)) for health risk assessment. The CR were ranged from 0-5.7 x 10(-1), 4.0 x 10(-1), 2.0 x 10(-1) and 1.0 x 10(-1) in small residential areas for children, adolescents, males and females, respectively. In roadside areas, the values ranged from 0-2.8 x 10(-1), 4.0 x 10(-1), 2.0 x 10(-1) and 2.8 x 10(-1) for children, adolescents, males and females, while 0-5.9 x 10(-1), 4.1 x 10(-1), 2.1 x 10(-1) and 1.6 x 10(-1) in industrial areas and 0-8.0 x 10(-1), 2.91 x 10(-1), 2.6 x 10(-1) and 3.9 x 10(-1) were calculated in household sites. All the CR values were found to be exceeding the US-EPA limit (10(-6)) recommending that the people in the study area are more prone to carcinogenic risk. Overall, it was concluded that due to presence of As in drinking water, these areas tend to be at higher cancer risks. To provide safe drinking water for the people living in these As-affected areas, urgent remedial and management steps are required.