Controls on the genesis of some high-fluoride groundwaters in India

Groundwater fluoride as a geochemical marker in the etiology of chronic kidney disease of unknown origin in Sri Lanka

“…Evapotranspiration lead to a precipitation of calcite, a lowering of calcium activity and increase of Na/Ca ratios which allowed an increase of fluoride levels in the solution. A significant feature was that due to irrigation and farming practices, there was an increase in the extent of the sodic soils which contributed to an increase of fluoride in groundwater and hence dental fluorosis (Jacks et al, 2005). This is also applicable to the dry zone of Sri Lanka where due to the irrigation practices and water impounded in reservoirs, the lower reaches tend to be very rich in sodic soils thereby affecting the geochemical balance of groundwater fluoride, a fact which will have an impact on the kidney disease etiology.…”

“…The climate change and the consequent evapotranspiration have been very high in these tropical lands with the resulting elevations of fluoride, Na, Ca and Mg in the groundwater. Jacks et al (2005) studied the controls on the genesis of fluoride rich groundwaters in India where there was an increase in the incidence of dental and skeletal fluorosis with 62 million people at risk. They observed that fluoride concentrations are governed by adsorption equilibria and by fluorite stability.…”

Principal component analysis of fluoride geochemistry of groundwater in Shanxi and Inner Mongolia, China

“…Chemically, F − and OH − are negatively charged and possess similar ionic radii, 1.33 Å for F − and 1.40 Å for OH − (Chidambaram et al, 2003;Jacks et al, 2005;Santaren et al, 1990). Therefore, OH − can replace the exchangeable F − from F-bearing minerals and enhance the F − concentration in groundwater (Dar et al, 2011;Guo et al, 2007).…”

Sources of contaminants and groundwater quality in the coastal part of a river delta

“…Fluoride occurs in a combined form in rocks and soil in wide variety minerals such as fluorspar (fluorite), cryolite, apatite, topaz and their corresponding host rocks such as granite, basalt, syenite, and shale (Apambire et al 1997; Ayoob and Gupta 2006;Buxton and Shernoff 1999;Edmunds and Smedley 2005;Hamilton et al 1982;Reddy and Prasad 2003;WHO 1994). According to Jacks et al (2005), fluoride is originated by condensation of soluble components due to evaporation and evapotranspiration. However, the absence of significant correlation between chloride and fluoride rules out this mechanism.…”