Title: Investigation of trace elements and F, its geochemistry and associated health risk in groundwater of industrial region of Sonbhadra district, Uttar Pradesh, India

Abstract

Coal mining and coal burning dominated region was selected to assess pollution load of the groundwater with reference to the trace elements (i.e. As, Hg, Cd, Cr, Cu, Fe, Mn, Zn, Ni,Co, and Pb) and F in Obra, Renukoot and Anpara industrial clusters of Sonbhadra district, Uttar Pradesh, India. 220 groundwater samples were collected during post- and pre-monsoon seasons. Piper diagram showed that most of the samples are of Ca-Mg-HCO3-Cl-SO4 type. Gibbs plot depicted that weathering of rock minerals has affected the hydrogeochemistry of the study area. Fluoride contamination was observed only in few borewells of Renukoot and Anpara whereas nitrate contamination was observed in most of the borewells of all the three clusters in both the seasons, as per WHO standards. The primary cause of nitrate contamination in the groundwater was found to be from anthropogenic sources such as sewage and manure. All three clusters were found to be severely contaminated with Fe, Pb, Cd, Cr, As and Hg in both the seasons. For all the three clusters, the mean values of heavy metal pollution (HPI) were found above the critical index in both the seasons. For the majority of groundwater samples across the clusters during both the seasons, substantial non-cancer health risk was observed due to target Hazard Quotient (THQ) values of Cr, Cd, As, Pb and Hg higher than unity. THQ values of trace elements and F showed that children are at higher risk than the adult of the study area during both the seasons. Carcinogenic risk due to Cr was observed highest followed by As and Pb. Pictorial representation of the affected persons showed mild to severe cases of dental fluorosis. Finding of this study may be used as a database by the government to make proper guidelines for the safe use of drinking water.