Integrated Python-GIS Assessment of Fluoride and Nitrate Contamination and Associated Health Risks in Groundwater of Eastern India

Groundwater enriched in fluoride (F⁻) and nitrate (NO₃⁻) poses significant health risks worldwide. Several studies have reported the health hazards associated with F⁻ and NO₃⁻ in groundwater; however, region-specific assessments remain limited in tropical regions of Eastern India. Therefore, to evaluate groundwater quality from a health perspective, a Python-assisted, GIS-based analytical approach, combined with hydrogeochemical interpretation, statistical analysis, and human health risk assessment, was implemented. A total of 83 groundwater samples were collected and analyzed for physicochemical and hydrogeochemical parameters during the post-monsoon (December 2022). Results indicated that 62% of the samples exceeded the permissible limit for F⁻ (1.5 mg/L), while 6% exceeded the NO₃⁻ limit (45 mg/L). The WQI, PIG, FPI, and NPI consistently indicated poor groundwater quality in contaminated zones. F⁻- enrichment was likely controlled by the dissolution of fluorine-bearing minerals, cation exchange, and rock-water interaction in alkaline conditions, whereas localized activities such as intensive agriculture, sewage leakage, and improper waste disposal governed NO₃⁻ pollution. Piper trilinear analysis revealed a dominant Ca–HCO₃ hydrochemical facies, with a gradual transition toward mixed water types. The total non-carcinogenic health index (TNHI) ranged from 0.09 to 9.89 for infants, 0.07 to 8.01 for children, and 0.08 to 9.57 for adults, indicating that nearly 75% of the samples posed combined non-carcinogenic health risks to infants, followed by adults (73%) and children (70%). The Python-assisted GIS approach enabled automation of water quality and health risk index calculations and spatial delineation of contamination hotspots, enhancing analytical reproducibility. These findings provided evidence supporting sustainable groundwater management in F⁻ and NO₃⁻ affected tropical regions.