Arsenic–Iron Relationships in Aquifers of North East India: Implications for Public Health and the Environment

Arsenic (As) contamination of groundwater in the Ganga–Brahmaputra–Meghna basin of India and Bangladesh poses severe risk to human health and the environment. Arsenic in the groundwater of this area is largely geogenic, derived from the microbial reductive dissolution of iron (Fe) oxyhydroxide and subsequent release of the sorbed As. The present study examined the correlation between As and Fe in groundwater sources in four districts of Manipur state, and in Cachar, Hailakandi, and Karimganj districts in the Barak Valley region of south Assam. Both the study areas are located in the northeastern region of India. The results reveal that As–Fe correlations in Manipur were more significant and positive, when compared to those in Barak Valley. The significance of these findings in the mobilization and transport of arsenic in the fluvial environment of these two areas of North East India, and in the prediction of arsenic-safe aquifers, are discussed and compared with existing literature. These findings, therefore, have implications in the sustainable management of groundwater resources in the study areas.