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

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 mu g g(-1), respectively. F-1 content in tree species was found in this order Azadirachta indica 47.32-55.76 mu g g(-1) > Prosopis juliflora 40.16-49.63 mu g g(-1) > Acacia tortilis 34.39-43.60 mu g g(-1). While in case of leafy vegetables, F-1 content order was Chenopodium album 54.23-98.42 mu g g(-1) > Spinacea oleracea 30.41-64.09 mu g g(-1) > Mentha arvensis 35.48-51.97 mu g g(-1). The order of F-1 content in crops was found as 41.04 mu g g(-1) Pennisetum glaucum > 13.61 mu g g(-1) Brassica juncea > 7.98 mu g 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.