Geochemical Assessment of Fluoride Pollution in Groundwater of Tribal Region in India

This study assessed the fluoride (F^?) pollution in groundwater samples (n?=?170) of tribal regions around Bailadila Iron Ore Mines [BIOM] Complex of Dantewada District, India. Weathering of carbonate and silicate clays were important geogenic sources of dissolved ions. A Piper diagram showed a Ca–HCO₃ water type, with positive chloro-alkaline indices illustrating the occurrence of direct base-exchange reactions. The F^? concentrations varied from 0.08 to 1.95 mg L^?1 with a mean value of 0.9?±?0.3 mg L^?1. Only two groundwater samples showed F^? concentrations?>?1.5 mg L^?1, the drinking water guideline established by the World Health Organization (WHO) and Bureau of Indian Standards (BIS). Factor analysis showed high loadings of HCO₃^? and F^?, indicating alkaline conditions, favoring the dissolution of F^? in the groundwater. The K _fluor value is less than 10^?10.6, indicating that the dissociation of fluorite is very slow. As a result, groundwater locations were under-saturated with respect to fluorite.