Nitrate and fluoride contamination in the groundwater in a tribal region of north Maharashtra, India: An account of health risks and anthropogenic influence

The qualitative assessment of groundwater and health risk is an integral step in sustainable development of the region. The present study mainly focuses on the assessment of human health risk in the Shahada tehsil of Nandurbar District, North Maharashtra, India due to the nitrate and fluoride contamination in subsurface water resources due to the anthropogenic inputs. In view of this, forty-five (45) representative water samples were collected in month of March 2019 and were assessed for major physiochemical parameters using guidelines of APHA standard procedures. The analytical results were compared with the drinking standards of World Health Organization (WHO) and Bureau of Indian (BIS). The analytical results depict that EC, TDS, TH, Ca2+, Mg2+, HCO3-, Cl-, NO3- and F- surpassed the desirable limit (DL) and permissible limit (PL). The statistical analysis includes Correlation Analysis (CA) and Principal component Analysis (PCA) has been used to ascertain the significant association among water quality parameters. Further, the degree of contamination and domestic suitability of water were evaluated by computing Pollution Index of Groundwater (PIG), Groundwater Quality Index (GWQI) and Human Health Risk Assessment (HHRA) mainly for nitrate and fluoride contamination. PIG results inferred that 6.66% samples have moderate, 73% insignificant pollution and 20% low pollution. GWQI results revealed that 14% samples (poor class), 62% samples (very poor class) and only 6.6% samples (unsuitable). Total Hazard Index (THI) of fluoride and nitrate indicates that about 51% of the infants, 84% of the children, 69% of the teenagers and 60% of the adults are at non -carcinogenic risk, as THI values of more than 1 were observed to be vulnerable to non -carcinogenic health hazard. The outcomes of the study may assist the government authorities and research scholars as well as the local communities to develop comprehensive strategies in the study area to overcome the health risk problems due to fluoride and nitrate contamination.