Hydrochemical characteristics and human health risk assessment of groundwater in the Shivalik region of Sutlej basin, Punjab, India

Shivalik region is one of the agri-intensive regions in Punjab, India, wherein groundwater quality is a major human health concern. In this study, a total of 57 groundwater samples were collected from the Rupnagar district of this region (one sample per 36 km2) to evaluate its quality, the role of hydrogeochemical processes in its contamination, and further their potential human health hazards. The results indicate that the major water chemistry is governed by carbonate weathering followed by silicate weathering. The Fe, Mg, Mn, Se, and HCO3- concentrations exceeded the BIS drinking water standards in 86, 51, 11, 9, and 79% of the samples, respectively. Piper and Durov plots indicated the dominance of Ca-HCO3- water types, followed by Ca-Mg-Cl- and Ca-Cl-. Furthermore, multivariate analyses indicated the geogenic origin for Fe, Mg, Mn, Se, SO42-, and anthropogenic sources (agrochemicals, cement factories, and fly ash) for NO3-, Cu, and Cr. The estimated carcinogenic risk of As and Cr falls under the very low (10-6) to low (10-5) risks category. Furthermore, the cumulative risk of non-carcinogenic contaminants (F-, U, NO3-) (HI-0.93) is at an alarming level and also close to the boundary line of USEPA limits (HI-1). There is an urgent need to undertake suitable policy measures for sustainability of groundwater quality.