Assessments of hydrogeochemical characteristics, water quality, and health risk of groundwater of Chapi-Nawabganj District of Bangladesh

Abstract

A total of 60 groundwater samples were collected over three seasons, aiming to assess hydrochemical characteristics, water quality, pollution level, and health risk. The concentration of Fe, Mn, and Pb exceeded almost 100% of samples in three seasons. The groundwater was found to be highly contaminated with Cd and Cr in the pre-monsoon and Ni in the monsoon. The order of major ion and trace metal concentrations is as follows: Ca2+ > Na+ > Mg2+ > K+; HCO3− > Cl− > SO42− > NO3− > PO43−, and Fe > Mn > Pb > Cd in three seasons. The groundwater was Ca-Mg-HCO3− type. The study suggests that the contamination sources are mostly geogenic as well as slightly anthropogenic. The water–rock interactions are the dissolution of calcite and dolomite, along with silicate weathering, which controls the hydrochemistry of the groundwater. The indices, including the Water Quality Index (WQI), and the Canadian Council of Ministers of the Environment (CCMEWQI), revealed that the groundwater quality in the area was moderately polluted. The Heavy Metal Pollution Index (HMPI), and human health risk assessment (HRA) illustrated that groundwater is a significant health hazard, indicating it is unsuitable for human consumption and suggesting treatment before drinking.