Groundwater Arsenic Contamination and Associated Health Risks in Bihar, India

Abstract

The extent of groundwater arsenic (As) contamination and associated health-risks were studied<br />in the four villages: Chaukia and Terahrasiya (Vaishali); Mamalkha and Masharu (Bhagalpur) in Bihar, India.<br />Groundwater samples were tested using the standard Silverdiethyledithiocarbamate method at 520nm by<br />Thermo UV-1 spectrophotometer. The As levels in both the districts exceeded the WHO standard of 10μg/L<br />for drinking water with a maximum value of 20μg/L in Vaishali and 143μg/L in Bhagalpur. However, the FAO<br />standard of 100μg/L of As for irrigation water was only exceeded in Bhagalpur. The calculated range of the<br />hazard index (HI) for Vaishali was 0.9 to 10, and for Bhagalpur was 10.40 to 40.47. Both ranges exceed the<br />accepted normal toxic HI of 1.00. The cancer risk was derived as 1-5/1000 people to 5-16/10,000 people in<br />Vaishali, and 7-21/1000 and 5-16/1000 people in Bhagalpur. Prevalence of skin pigmentation was double in<br />Vaishali in comparison to Bhagalpur. The analysis of principal components showed that only two components<br />had a fundamental role in defining variance for cancer risk assessment. A more extensive screening of As<br />contamination of groundwater and a follow-up clinical study are necessary to accurately assess the likelihood<br />of As-related cancers in these districts.