Distribution, genesis and geochemical modeling of fluoride in the water of tribal area of Bijapur district, Chhattisgarh, central India

Abstract The present study has been carried out to determine the sources and distribution of fluoride (F−) contamination in the water of district Bijapur, Chhattisgarh, central India. For this study, 45 water samples were collected from surface and groundwater from shallow and deeper aquifers. It was observed that 50% of groundwater samples have elevated F− level and varies from 0.1 to 7.1 mg/L, though, F− level in water bodies was below the WHO maximum permissible limit (1.5 mg/L). The major ions of water samples reveal the dominance of Ca–Mg–HCO3 hydrochemical facies. This study suggests F− contaminated water shows a significant correlation with Cl− which further supported by statistical correlation. Analysis of rocks and sediments from the study area suggests leaching of minerals like biotite, hornblende, and richterite which are likely sources for elevated F− level in groundwater. Gibbs diagram reveals the dominance of the evaporative process for contaminated water by F− in the study area. Due to improper awareness, the local tribal population (≈2, 55,000) of the area is consuming F− enriched groundwater and vulnerable to dental and skeletal fluorosis. Thus, surface and uncontaminated water w.r.t F− should be developed for providing safe water to the inhabitants.