Geochemical and health risk assessment of fluoride and nitrate toxicity in semi-arid region of Anantapur District, South India

This paper reports to the fluoride and nitrate concentration in groundwater resources of the semi-arid region of Anantapur district, South India, and its related potential health risk assessment issues with the resident peoples. For this purpose, 50 groundwater samples were analyzed for hydrochemical parameters including major ions, fluoride and nitrate. The results revealed that most of the groundwater samples are alkaline in nature. Hydrochemical type of groundwater in the study area mainly Na+-K+-Cl--SO42-and few samples belong to Na+-K+-HCO3-. Non carcino-genic health risks due to fluoride and nitrate exposure through consumption of groundwater were assessed using the USEPA method. In the study area groundwater samples, fluoride and nitrate concentration ranges from 1.2 to 5.9 mg/L and 36 to 92 mg/L. Based on these results, 86% of fluoride (>1.5 mg/L) and 94% of the nitrate (>45 mg/L) in ground-water samples exceed the permissible limit. The Total Hazard Index (THI) quotients for adults, children and infants had health hazards (THI > 1) in 98%, 88%, and 80% of samples, respectively. Hence, proper precautionary measures have to be taken to control health risk in this area.