Mapping of fluoride endemic area and assessment of F⁻¹ accumulation in soil and vegetation

Abstract

The prevalence of fluorosis is mainly due to the consumption of more fluoride (F⁻¹) through drinking water, vegetables, and crops. The objective of the study was mapping of F⁻¹ endemic area of Newai Tehsil, Tonk district, Rajasthan, India. For the present study, water, soil (0–45 cm), and vegetation samples were collected from 17 villages. Fluoride concentration in water samples ranged from 0.3 to 9.8 mg/l. Out of 17 villages studied, the amounts of F⁻¹ content of eight villages were found to exceed the permissible limits. Labile F⁻¹ content and total F⁻¹ content in soil samples ranges 11.00–70.05 mg/l and 50.3–179.63 μg g⁻¹, respectively. F⁻¹ content in tree species was found in this order Azadirachta indica 47.32–55.76 μg g⁻¹ > Prosopis juliflora 40.16–49.63 μg g⁻¹ > Acacia tortilis 34.39–43.60 μg g⁻¹. While in case of leafy vegetables, F⁻¹ content order was Chenopodium album 54.23–98.42 μg g⁻¹ > Spinacea oleracea 30.41–64.09 μg g⁻¹ > Mentha arvensis 35.48–51.97 μg g⁻¹. The order of F⁻¹ content in crops was found as 41.04 μg g⁻¹ Pennisetum glaucum > 13.61 μg g⁻¹ Brassica juncea > 7.98 μg g⁻¹ Triticum sativum in Krishi Vigyan Kendra (KVK) farms. Among vegetation, the leafy vegetables have more F⁻¹ content. From the results, it is suggested that the people of KVK farms should avoid the use of highly F⁻¹ containing water for irrigation and drinking purpose. It has been recommended to the government authority to take serious steps to supply drinking water with low F⁻¹ concentration for the fluorosis affected villages. Further, grow more F⁻¹ hyperaccumulator plants in F⁻¹ endemic areas to lower the F⁻¹ content of the soils.