Seasonal assessment of groundwater contamination, health risk and chemometric investigation for a hard rock terrain of western India

Abstract

Groundwater quality in the Shivganga river basin, Western India, was evaluated by an integrated approach using pollution index of groundwater (PIG), health risk assessment (HRA) and chemometric analysis. Sixty eight (68) representative groundwater samples were collected and analysed for pH, Electrical conductivity (EC), Total dissolved solids (TDS), major cation and anion during pre- (PRM) and post (POM)-monsoon seasons of 2016. Hydro-chemical analysis inferred that EC, total hardiness, alkalinity, boron and fluoride are exceeding the permissible limits of the World Health Organisation (WHO). PIG was computed based on considered physicochemical parameters and WHO drinking standards to ascertain the degree of pollution level. PIG results inferred that about 6% samples fall in moderate, 12% in low and 82% in insignificant pollution in PRM season; while, 12% of sample fall within low, 88% insignificant pollution in POM season. HRA was carried to know the health impacts of boron and fluoride toxicity on infants, children and adults. HRA results suggest that children are more susceptible to non carcinogenic health risk than infants and adults. Chemometric analysis included correlation matrix (CM), principal component analysis (PCA) and cluster analysis (CA) to know the relationship between water quality variables and their collective influence on overall groundwater quality. CM and PCA suggested that, inputs of TDS, Mg, NO3, Na, Cl, and SO4 are elevated due to rainfall and anthropogenic activities. These techniques are useful to evaluate the influence of seasonal variation of natural or anthropogenic processes controlling the groundwater quality in the study region.