Pyroclastic fluoride in ground waters in some parts of Tadpatri Taluk, Anantapur district, Andhra Pradesh.

Fluorosis is a disease affecting the teeth and bones and caused by excessive ingestion of fluoride through drinking water. Fluoride concentration in ground water samples of the study area varies from 1.2 to 2.1 ppm., which is much above the permissible limit. The probable source of fluoride in ground water is fluoride bearing minerals like apatite, micas and clay minerals etc., present in the country rocks like shales and pyroclastic materials of the study area. The sample survey is carried out to know the incidence of fluorosis in this area which reveals that more than 43% of the inhabitants are affected by dental fluorosis and 0.4% by skeletal fluorosis.