Untitled

Worldwide contamination of water by fluoride

“…The longer residence time of groundwater in the weathered aquifer zone and low rate of dilution are favorable factors for the dissolution of fluorine-bearing minerals (Raju et al 2009). Fluoride in the range of 0.1-14.8 mg/L was reported by Sharma et al (2011) in Agra district, while Gupta et al (1999) reported fluoride in the range of 0.11-12.80 mg/L (Table 5) in the same district. High fluoride contamination here was accounted by weathering of rocks accompanied by evaporation of groundwater (Sharma et al 2011).…”

“…(2009),Salve et al (2008),Singh et al (2011),Vikas et al (2009),Rao (2009),Kantharaja et al (2012),Guo et al (2012),Gupta et al (1999),Madhnure et al et al (1993),Rao et al (1993),Chakraborti et al (2000),Kundu et al (2001), Farooqi et al (2007a), Brindha et al (2011), Dar et al (2011), Kim et al (2011), Singh et al (2011), Jabal et al (2014) -Calcium Chakraborti et al (2000), Rao (2009) Jacks et al (1993), Gupta et al (1999), Das et al (2003), Vasquez et al (2006), Ramanaiah et al (2006), Farooqi et al (2007a), Madhnure et al (2007), Shaji et al (2007), Mondal et al (2009), Vikas et al (2009), Brindha et al (2011), Dar et al (2011), Singh et al (2011), Guo et al (2012), Xu et al (2013), Jabal et al (2014), Li et al (2015) Magnesium Rao (2009) Gupta et al (1999), Farooqi et al (2007a), Xu et al (2013) Hardness Rao et al (1993), Das et al (2003) Bicarbonate Jacks et al (1993), Gupta et al (1999), Kundu et al (2001), Vasquez et al (2006), Farooqi et al (2007a), Madhnure et al (2007), Rao (2009), Keshavarzi et al (2010), Brindha et al (2011), Dar et al (2011), Singh et al (2011), Kantharaja et al (2012), Jabal et al (2014), Singh and Mukherjee (clear from the table that in general none of the parameter show good correlation EC electrical conductivity, O 18 heavy oxygen isotope Environ Chem Lett…”

Assessment of Groundwater Quality with Respect to Fluoride

“…A statistical method adopted to evaluate the correlation between various ground water quality parameters. (2003) Andhra Pradesh (Anantpur) 0.56-5.80 Rao and Devadas (2003) Orissa (Nayagarh district) 0.16-10.10 Kundu et al (2001) Gujarat (Ahmedabad) 0.50-0.72 Barot (1998) Uttar Pradesh Agra (Kheragarh) 0.11-12.80 Gupta et al (1999) Andhra Pradesh (Vishakapatnam) 0.35-8.35 Sarma and Rao (1997) The analytical precision for the measurement of cations and anions, indicated by the ionic balance error (IBE), was computed on the basis of ions measured. The value of IBE was found within a standard limit of ±5%.…”

“…Though fluoride enters the body through food, water, industrial exposure, drugs, cosmetics, etc., drinking water is the major contributor (75-90% of daily intake) (Sarala and Rao 1993). The studies carried out by various researchers on groundwater quality with respect to fluoride across India, including Gujarat, are reported elsewhere (Shaji et al 2007;Asadi et al 2007;Misra et al 2006;Sujatha 2003;Rao and Devadas 2003;Sarma and Rao 1997;Madhnure et al 2007;Kaushik et al 2004;Gupta et al 2006;Kundu et al 2001;Barot 1998;Gupta et al 1999) and are presented in Table 1.…”

Fluoride in Drinking Water: Health Effects and Remediation

“…It has been reported that once the solubility limit for fluorite (CaF 2 ) is reached, an inverse relationship will exist between fluoride and calcium concentrations (Ozsvath 2009). Many studies have found a strong association between high fluoride and soft, alkaline (i.e., sodium-bicarbonate) groundwater that is depleted in calcium (Bårdsen et al 1996;Chae et al 2006aChae et al , 2007Conrad et al 1999;Dhiman and Keshari 2006;Earle and Krogh 2004;Gupta et al 1999;Handa 1975;IGRAC 2003a;Kohut et al 2001;Pekdeger et al 1992;Robertson 1986;Whittemore et al 1993). Other than these, pH and the development of secondary minerals are responsible in high mobility of fluoride in soil (Jacks et al 2005).…”