High fluoride incidence in groundwater and its potential health effects in parts of Raigarh District, Chhattisgarh, India

High concentrations of fluoride (F⁻) in drinking water are harmful to human health. Knowledge of spatiotemporal distribution of F⁻ content in groundwater is thus a prerequisite for taking preventive measures. This communication reports F⁻ incidence in groundwater and its relation with the prevalence of fluorosis in Tamnar area, Raigarh District, Chhattisgarh, India. Nearly 18% of the sampled wells had F⁻ concentrations above the desirable limit (> 1.0 mg/l), the highest value being 8.8 mg/l. High F⁻ concentrations primarily occurred in coal-bearing Barakar Formation of the Gondwana Supergroup. Prevalence of dental fluorosis was observed in five villages, viz. Dholnara, Kunjhemura, Muragaon, Pata and Saraitola; whereas skeletal fluorosis was found to occur only in Muragaon. The spatial distribution of F⁻ in groundwater, as indicated by hydrogeochemical analyses, corroborated well with the prevalence of dental and skeletal fluorosis. It is envisaged that, in addition to the people already affected, a large fraction of the population in the area is at potential risk, especially considering that the region falls in the coal mining and industrial belt. The health-risk map prepared using a Geographic Information System provides baseline information in taking mitigation measures