GIS–entropy based appraisal of groundwater quality, health hazards, and irrigation potential in the Samalpatti–Sevathur carbonatite terrains, South India

Groundwater pollution is an emerging universal issue. This study evaluates groundwater suitability for drinking and irrigation in Samalpatti-Sevathur carbonatite complexes, focusing on Fluoride (F⁻), and Nitrate (NO₃⁻) contamination and associated health risks. Seventy-five groundwater samples were collected in February 2025 and analyzed. F⁻ concentration in groundwater ranged 0.18-4.6 mg/L, and NO₃⁻ ranged 4.99-182.55 mg/L. Only 33.3% of F⁻ and 57.7% of NO₃⁻ samples met standards, with 37.3% samples deemed potable by Entropy Water Quality Index (EWQI). Ca²⁺ reflects a negative correlation with F⁻ and positive with NO₃⁻, indicating geogenic F⁻ from mineral dissolution and anthropogenic NO₃⁻ input, supported by…

• AN
  Arthritis National Research Foundation
• NR
  National Research Foundation
• DO
  Department of Science and Technology, Ministry of Science and Technology, India