Fluoride Action Network


… One of the major objectives of our research group is the production of geochemical maps showing the distribution of elements or important chemical species in the surface and groundwater of Sri Lanka. A geochemical data bank is now being prepared with the assistance of the Water Supply and Drainage Board and the Water Resources Board of Sri Lanka. For example, in a preliminary survey carried out on the relationship between fluoride ions in drinking water and the incidence of dental diseases, areas with abundant fluoride concentrations in the water (> 3 ppm) were identified. Dental fluorosis was found to be common in areas where mineral deposits  such as apatite are found or where hot springs with exhalations of fluorine occur. In contrast, those areas with very little or no fluoride, such as the central region of Sri Lanka, had a high incidence of dental caries. The intensity of rainfall also plays a major role in the leaching of fluoride ions from soils and probably contributes to the formation of a low fluoride zone in the wet central region of Sri Lanka.

*Original report online at https://www.researchgate.net/publication/329886103_the_hydrogeochemical_atlas_of_sri_lanka