Spatial analysis of groundwater quality and human health risk assessment in parts of Raebareli district, India

Provision of safe drinking water sources is one of the most important agenda of the governing bodies in developing countries across the globe. Hence, the current study was taken up to assess the overall groundwater quality and the spatial distribution of the physico-chemical parameters governing the groundwater quality in Raebareli district (North India). In general, the groundwater was found to be slightly alkaline, with the order of ionic abundance being F− < K+ < Ca2+ < NO3− < Mg2+ < SO42− < Na+ < HCO3−. The results of ‘Pollution Index of Groundwater’ (PIG) suggest that around 50% of the samples were in the category of ‘insignificant pollution’, with 1 sample each under ‘high’ and ‘very high’ pollution categories. The dominant water type in the study area was found to be ‘mixed CaNaHCO3 type’ through hydrochemical facies assessment. The spatial distribution suggests that the north and central parts were the most affected areas with respect to PIG. The non-carcinogenic effects of consuming water contaminated with F− and NO3− were assessed through Hazard Quotient (HQ) and Total Hazard Index (THI) values. The HQFluoride varies between 0.16–6.34, 0.12–4.69, and 0.14–5.54 for the children, male, and female, respectively. The HQNitrate varies between 0.03–4.96, 0.02–3.67, and 0.02–4.33 in the case of children, male, and female, respectively. The spatial distribution of THI suggested that central parts of the study area were under high risk. The potential health risks to the residents in the study area should cause immediate attention from the society, governing authorities, and the research community.