References

  1. U. Rizwan, M.S. Zafar, N. Shahani, Potential fluoride toxicity from oral medicaments: A review, Iran J. Basic Med. Sci., 4 (2017) 841–848.
  2. EU (European Union) Council: Council Directive 98/83/EC of 3 November (1998) on the Quality of Water Intended for Human Consumption [online]. Available at http://eurlex.europa.eu/legalcontent/EN/TXT/PDF/?uri=CELEX-:31998L0083&from=EN (1998).
  3. WHO (World Health Organization): Guidelines for Drinking-Water Quality, 4th ed. [online] (2011).
  4. BIS (Bureau of Indian Standards): Specification for Drinking Water IS 10500: 2012 New Delhi[online]. Available at India http://cgwb.gov.in/Documents/WQ-standards.pdf. (2012).
  5. E.Y. Wong, M.K. Stenstrom, Onsite defluoridation system for drinking water treatment using calcium carbonate, J. Environ. Manage., 216 (2017) 270–274.
  6. M. Zarrabi, Removal of fluoride ions by ion exchange resin: kinetic and equilibrium studies, Environ. Eng. Manag. J., 13 (2014) 205–214.
  7. M.F. Chang, J.C. Liu, Precipitation removal of fluoride from semiconductor wastewater, J. Environ. Eng., 133(4) (2007). doi.org/10.1061/(ASCE)0733-9372(2007)133:4(419).
  8. B.R. Min, A.L. Gill, W.N. Gill, A note on fluoride removal by reverse osmosis, Desalination, 49 (1984) 89–93.
  9. M. Bodzek, K. Konieczny, A. Kwiecińska, Application of membrane processes in drinking water treatment – state of art, Desal. Water Treat., 35 (2011) 164–184.
  10. G. Zhang, Y. Gao, Y. Zhang, P. Gu, Removal of fluoride from drinking water by a membrane coagulation reactor (MCR), Desalination, 177 (2005) 143–155.
  11. K. Hu, J.M. Dickson, Nanofiltration membrane performance on fluoride removal from water, J. Membr. Sci., 279 (2006) 529–538.
  12. S. Gmar, A. Chagnes, I.B.S. Sayadi, J.F. Fauvarque, M. Tlili, M.B. Amor, Semiempirical kinetic modelling of water desalination by electrodialysis processes, Sep. Sci. Technol., 52 (2017) 574–581.
  13. Y.J. Shih, M.T. Tsai, Y.H. Huang, Mineralization and defluoridation of 2,2,3,3-tetrafluoro-1-propanol (TFP) by UV oxidation in a novel three-phase fluidized bed reactor (3P-FBR), Water Res., 47 (2013) 2325–2330.
  14. C. Okoli, M. Boutonnet, L. Mariey, S. Järås, G. Rajarao, Application of magnetic iron oxide nanoparticles prepared from microemulsions for protein purification, J. Chem. Tech. Biotech., 86 (2011) 1386–1393.
  15. N. Suneetha, K.P. Rupa, V. Sabitha, K.K. Kumar, S. Mohanty, A.S. Kanagasabapathy, R. Pragna, Defluoridation of water by a one step modification of the Nalgonda technique, Annals Trop. Med. Public Heal., 1 (2008) 56–58.
  16. B. Pan, J. Xu, B. Wu, Z. Li, X. Liu, Enhanced removal of fluoride by polystyrene anion exchanger supported hydrous zirconium oxide nanoparticles, Environ. Sci. Tech., 47 (2013) 9347–9354.
  17. H.Z. Zhao, W. Yang, J. Zhu, J.R. Ni, Defluoridation of drinking water by combined electrocoagulation: effects of the molar ratio of alkalinity and fluoride to Al(III), Chemosphere, 74 (2009) 1391–1395.
  18. N. Drouiche, H. Lounici, M. Drouiche, N. Mameri, N. Ghaffour, Removal of fluoride from photovoltaic wastewater by electrocoagulation and products characteristics, Desal. Water Treat., 7 (2009) 236–241.
  19. N. Drouiche, S. Aoudj, H. Lounici, H. Mahmoudi, N. Ghaffour, M.F.A Goosen, Development of an empirical model for fluoride removal from photovoltaic wastewater by electrocoagulation process, Desal. Water Treat., 29 (2011) 96–102.
  20. S. Aoudj, A. Khelifa, N. Drouiche, M. Hecini, HF wastewater remediation by electrocoagulation process, Desal. Water Treat., 51 (2013) 1596–1602.
  21. S. Aoudj, A. Khelifa, N. Drouiche, M. Hecini, Removal of fluoride and turbidity from semiconductor industry wastewater by combined coagulation and electroflotation, Desal. Water Treat., 57 (2016) 18398–18405.
  22. S. Aoudj, B. Cheknane, H. Zemmouri, F. Zermane, A. Khelifa, M. Hecinia, N. Drouiche, Kinetics and adsorption isotherm for the removal of fluoride and chromium (VI) from wastewater by electrocoagulation, Desal. Water Treat., 82 (2017) 262–270.
  23. N. Mumtaz, G. Pandey, P.K. Labhasetwar, Global fluoride occurrence, available technologies for fluoride removal, and electrolytic defluoridation: a review, Crit. Rev. Environ. Sci. Technol., 45 (2015) 2357–2389.
  24. P.G. Hiremath, T. Theodore, Modelling of fluoride sorption from aqueous solution using green algae impregnated with zirconium by response surface methodology, Adsorpt. Sci. Technol., 35 (2017) 194–217.
  25. M. Naushad, T. Ahamad, B.M. Al-Maswari, A. Abdullah Alqadami, S.M. Alshehri, Nickel ferrite bearing nitrogen-doped mesoporous carbon as efficient adsorbent for the removal of highly toxic metal ion from aqueous medium, Chem. Eng. J., 330 (2017) 1351–1360.
  26. A.A. Alqadami, M. Naushad, Z.A. AlOthman, A.A. Ghfar, Novel metal-organic framework (MOF) based composite material for the sequestration of U(VI) and Th(IV) metal ions from aqueous environment, ACS Appl. Mater. Interfaces, 9 (2017) 36026–36037.
  27. M. Naushad, S. Vasudevan, G. Sharma, A. Kumar, Z.A. AlOthman, Adsorption kinetics, isotherms, and thermodynamic studies for Hg2+ adsorption from aqueous medium using alizarin red-S-loaded amberlite IRA-400 resin, Desal. Water Treat., 57 (2016) 18551–18559.
  28. Z.A. ALOthman, R. Ali, M. Naushad, Hexavalent chromium removal from aqueous medium by activated carbon prepared from peanut shell: Adsorption kinetics, equilibrium and thermodynamic studies, Chem. Eng. J., 184 (2012) 238–247.
  29. M. Naushad, Z.A. ALOthman, M. Islam, Adsorption of cadmium ion using a new composite cation-exchanger polyaniline Sn(IV) silicate: Kinetics, thermodynamic and isotherm studies, Int. J. Env. Scie. Technol., 10 (2013) 567–578.
  30. M.R. Awual, M.M. Hasan, G.E. Eldesoky, M.A. Khaleque, M.M. Rahman, M. Naushad, Facile mercury detection and removal from aqueous media involving ligand impregnated conjugate nanomaterials, Chem. Eng. J., 290 (2016) 243–251.
  31. E. Daneshvar, A. Vazirzadeh, A. Niazi, M. Kousha, M. Naushad, A. Bhatnagar, Desorption of Methylene blue dye from brown macroalga: Effects of operating parameters, isotherm study and kinetic modeling, J. Cleaner Production, 152 (2017) 443–453.
  32. A.A. Alqadami, M. Naushad, Z.A. AlOthman, T. Ahamad, Adsorptive performance of MOF nanocomposite for methylene blue and malachite green dyes: Kinetics, isotherm and mechanism, J. Environ. Manag., 223 (2018) 29–36.
  33. K. Deepa, C. Prasad, N.V.V. Jyothi, M. Naushad, S. Rajendran, S. Karlapudi, S.H. Kumar, Adsorptive removal of Pb (II) metal from aqueous medium using biogenically synthesized and magnetically recoverable core-shell structured AM@Cu/Fe3O4 nanocomposite, Desal. Water Treat., 111 (2018) 278–285.
  34. M. Naushad, T. Ahamad, G. Sharma, H. Ala’a AlMuhtaseb, A.B. Albadarin, M.M. Alam, Z.A. ALOthman, S.M. Alshehri, A.A. Ghfar, Synthesis and characterization of a new starch/SnO2 nanocomposite for efficient adsorption of toxic Hg2+ metal ion, Chem. Eng. J., 300 (2016) 306–316.
  35. A.B. Albadarin, M.N. Collins, M. Naushad, S. Shirazian, Activated lignin–chitosan extruded blends for efficient adsorption of methylene blue, Chem. Eng. J., 307 (2017) 264–272.
  36. M. Naushad, Z.A. ALOthman, Separation of toxic Pb2+ metal from aqueous solution using strongly acidic cation-exchange resin: analytical applications for the removal of metal ions from pharmaceutical formulation, Desal. Water Treat., 53 (2015) 2158–2166.
  37. A. Shahat, M.R. Awual, Mu. Naushad, Functional ligand anchored nanomaterial based facial adsorbent for cobalt(II) detection and removal from water samples, Chem. Eng. J., 271 (2015) 155–163.
  38. M. Naushad, Surfactant assisted nano-composite cation exchanger: Development, characterization and applications for the removal of toxic Pb2+ from aqueous medium, Chem. Eng. J., 235 (2014) 100–108.
  39. M. Naushad, Z.A. AlOthman, G. Sharma, Inamuddin, Kinetics, isotherm and thermodynamic investigations for the adsorption of Co(II) ion onto crystal violet modified amberlite IR-120 resin, Ionics, 21 (2015) 1453–1459.
  40. M. Naushad, Z. Abdullah ALOthman, M. RabiulAwual, S.M. Alfadul, T. Ahamad, Adsorption of rose Bengal dye from aqueous solution by amberlite Ira-938 resin: kinetics, isotherms, and thermodynamic studies, Desal. Water Treat., 57 (2016) 13527–13533.
  41. M. Naushad, Z.A. ALOthman, M.M. Alam, M. RabiulAwual, G.E. Eldesoky, M. Islam, Synthesis of sodium dodecyl sulfate-supported nanocomposite cation exchanger: Removal and recovery of Cu2+ from synthetic, pharmaceutical and alloy samples, J. Iran. Chem. Soc. 12 (2015) 1677–1686.
  42. M. Naushad, Z.A. ALOthman, M.R. Awual, M.M. Alam, G.E. Eldesoky, Adsorption kinetics, isotherms, and thermodynamic studies for the adsorption of Pb2+ and Hg2+ metal ions from aqueous medium using Ti(IV) iodovanadate cation exchanger, Ionics, 21 (2015) 2237–2245.
  43. M. Naushad, T. Ahamad, Z.A. Alothman, M.A. Shar, N.S. AlHokbany, S.M. Alshehri, Synthesis, characterization and application of curcumin formaldehyde resin for the removal of Cd2+ from wastewater: Kinetics, isotherms and thermodynamic studies, J. Ind. Eng. Chem., 29 (2015) 78–86.
  44. M. Naushad, Z.A. ALOthman, Inamuddin, H. Javadian, Removal of Pb(II) from aqueous solution using ethylene diamine tetra acetic acid-Zr(IV) iodate composite cation exchanger: Kinetics, isotherms and thermodynamic studies, J. Ind. Eng. Chem., 25 (2015) 35–41.
  45. Z.A. ALOthman, M.M. Alam, M. Naushad, Heavy toxic metal ion exchange kinetics: Validation of ion exchange process of composite cation exchanger nylon 6,6 Zr(IV) phosphate, J. Ind. Eng. Chem., 19 (2013) 956–960.
  46. M.R. Awual, M.M. Hasan, A. Shahat, M. Naushad, H. Shiwaku, T. Yaita, Investigation of ligand immobilized nano-composite adsorbent for efficient cerium(III) detection and recovery, Chem. Eng. J., 265 (2015) 210–218.
  47. A. Shahat, M.R. Awual, M.A. Khaleque, M.Z. Alam, M. Naushad, A.M.S. Chowdhury, Large-pore diameter nano-adsorbent and its application for rapid lead (II) detection and removal from aqueous media, Chem. Eng. J., 273 (2015) 286–295.
  48. M.K. Uddin, M.M. Salah, Statistical analysis of Litchi chinensis’s adsorption behavior toward Cr(VI) ion, Appl. Water Sci., 8 (2018) 140.
  49. A. Khatoon, M.K. Uddin, R.A.K. Rao, Adsorptive remediation of Pb (II) from aqueous media using Schleicheraoleosa bark, Environ. Technol. Innov., 11 (2018) 1–14.
  50. S. Shakoor, A. Nasar, Adsorptive decontamination of synthetic wastewater containing crystal violet dye by employing Terminalia arjuna sawdust waste, Groundwater Sustain. Develop., 7 (2018) 30–38.
  51. G. Sharma, Mu. Naushad, D. Pathania, A. Mittal, G.E. El-Desoky, Modification of Hibiscus cannabinus fiber by graft copolymerization: application for dye removal, Desal. Water Treat., 55 (2015) 3114–3121.
  52. S.S. Waghmare, T. Arfin, Fluoride removal by industrial, agricultural and biomass wastes as adsorbents: review, Inter. J. Adv. Res. Innov. Idea, 1 (2015) 628–653.
  53. S. Joshi, M. Adhikari, K.K. Pradhananga, Adsorption of fluoride ion onto zirconyl-impregnated activated carbon prepared from lapsi seed stone, J. Nepal Chem. Soc., 30 (2012) 13–23.
  54. M. Islam, M. Naushad, R. Patel, Polyaniline/basic oxygen furnace slag nanocomposite as a viable adsorbent for the sorption of fluoride from aqueous medium: Equilibrium, thermodynamic and kinetic study, Desal. Water Treat., 54 (2015) 450–463.
  55. M.K. Uddin, R.A.K. Rao, K.V.V. Mouli, The artificial neural network and Box-Behnken design for Cu2+ removal by the pottery sludge from water samples: Equilibrium, kinetic and thermodynamic studies, J. Mol. Liq., 266 (2018) 617–627.
  56. S. Jagtap, D. Thakre, S. Wanjari, S. Kamble, N. Labhsetwar, S. Rayalu, New modified chitosan-based adsorbent for defluoridation of water, J. Colloid Interface Sci., 332 (2009) 280–290.
  57. W. Yang, X. Dou, Y. Li, D. Mohan, C.U. Pittman, Y.S. Ok, Performance and mass transfer of aqueous fluoride removal by a magnetic alumina aerogel, RSC Adv., 6 (2016) 112988–112999.
  58. R.A.K. Rao, S. Ikram, M.K. Uddin, Removal of Cr (VI) from aqueous solution on seeds of Artimisiaabsinthium (novel plant material), Desal. Water Treat., 54 (2015) 3358–3371.
  59. B. Godboley, P. Nagarnaik, Groundnut shell: effective adsorbent for defluoridation from aqueous solution, Int. J. Civil Eng. Tech., 7 (2016) 51–60.
  60. M.K. Uddin, A review on the adsorption of heavy metals by clay minerals, with special focus on the past decade, Chem. Eng. J., 308 (2017) 438–462.
  61. L.V. Baia, W.C. Souza, R.J.F. de-Souza, C.O. Veloso, S.S.X. Chiaro, M.A.G. Figueiredo, Removal of sulfur and nitrogen compounds from diesel oil by adsorption using clays as adsorbents, Energy Fuels, 31 (2017) 11731–11742.
  62. A.A. Adeyemo, I.O. Adeoye, O.S. Bello, Adsorption of dyes using different types of clay: A review, Appl. Water Sci., 7 (2017) 543–568.
  63. Qamruzzaman, A. Nasar, Treatment of acetamiprid insecticide from artificially contaminated water by colloidal manganese dioxide in the absence and presence of surfactants, RSC Adv., 4 (2014) 62844–62850.
  64. K. Styszko, K. Sosnowska-Nosek, M. Motak, K. Bester, Preliminary selection of clay minerals for removal of pharmaceuticals, bisphenol a and triclosan in acidic and neutral aqueous solutions, Com. Rend. Chim., 18 (2015) 1134–1142.
  65. R.A.K. Rao, M. Kashifuddin, Adsorption studies of Cd (II) on ball clay: comparison with other natural clays, Arab. J. Chem., 9 (2016) 1233–1241.
  66. R.A.K. Rao, M. Kashifuddin, Adsorption properties of coriander seed powder (Coriandrum sativum): extraction and pre-concentration of Pb (II), Cu (II) and Zn (II) ions from aqueous solution, Adsorpt. Sci. Technol., 30 (2012) 127–146.
  67. R.A.K. Rao, M. Kashifuddin, Pottery glaze—an excellent adsorbent for the removal of Cu (II) from aqueous solution, Chin. J. Geochem. (Acta Geochim.), 31 (2012) 136–146.
  68. M. Shamsuddin, A. Nasar, Thermodynamic properties of cadmium telluride, High Temp. Sci., 28 (1988) 245–254.
  69. M.A. Lennon, H. Whelton, D. O’Mullane, J. Ekstrand, Fluoride, WHO Guidelines for Drinking-Water Quality [online], 2004.
  70. S. Gupta, S. Banerjee, Fluoride accumulation in crops and vegetables and dietary intake in a fluoride-endemic area of west Bengal, Fluoride, 44 (2011) 153–157.
  71. A.M. Abdelgawad, K. Watanabe, S. Takeuchi, Water-rock interaction study on the occurrence of fluoride-rich groundwater at Mizunami area, Japan Environ. Asia, 2 (2009) 20–29.
  72. C.J. Chuah, H.R. Lye, A.D. Ziegler, S.H. Wood, C. Kongpun, S. Rajchagool, Fluoride: a naturally-occurring health hazard in drinking-water resources of Northern Thailand, Sci. Total Environ., 545–546 (2016) 266–279.
  73. Water Treatment: Public Utility Board [online] Available at: https://web.archive.org/web/20090326084915, http://www.pub.gov.sg/GENERAL/Pages/WaterTreatment.aspx (2008).
  74. M.S. Shaharuddin, Y.M. Kamil, Y.M. Ismail, R.M. Firuz, I.S. Aizat, A.M. Yunus, Fluoride concentration in Malaysian drinking water, American-Eurasian, J. Agric. Environ. Sci., 6 (2009) 417–420.
  75. H. Chen, M. Yan, X. Yang, Z. Chen, G. Wang, D. Schmidt-Vogt, Y. Xu, J. Xu, Spatial distribution and temporal variation of high fluoride contents in groundwater and prevalence of fluorosis in humans inYuanmou County, Southwest China, J. Hazard. Mater., 235 (2012) 201–209.
  76. Drinking Water Quality for the Period of October: Water Supplies Department, The Government of Hong Kong Special Administrative Region [online], 2013.
  77. Y. Kim, J.Y. Kim, K. Kim, Geochemical characteristics of fluoride in groundwater of Gimcheon, Korea: lithogenic and agricultural origins, Environ. Earth Sci., 63 (2011) 1139–1148.
  78. A.K. Batabyal, S. Gupta, Fluoride-contaminated groundwater of Birbhum District, West Bengal, India: interpretation of drinking and irrigation suitability and major geochemical processes using principal component analysis, Environ. Monit. Assess., 189 (2017) 369.
  79. B.R. Pant, Groundwater quality in the Kathmandu valley of Nepal, Environ. Monit. Assess., 178 (2011) 477–485.
  80. A. Farooqi, H. Masuda, M. Kusakabe, M. Naseem, N. Firdous, Distribution of highly arsenic and fluoride contaminated groundwater from East Punjab, Pakistan, and the controlling role of anthropogenic pollutants in the natural hydrological cycle, Geochem. J., 41 (2007) 213–234.
  81. A.K.M. Fazlul-Hoque, M. Khaliquzzaman, M.D. Hossain, A.H. Khan, Fluoride levels in different drinking water sources in Bangladesh, Fluoride, 36 (2003) 38–44.
  82. R. Chandrajith, S. Nanayakkara, K. Itai, T.N.C. Aturaliya, C.B. Dissanayake, T. Abeysekera, K. Harada, T. Watanabe, A. Koizumi, Chronic kidney diseases of uncertain etiology (CKDue) in Sri Lanka: geographic distribution and environmental implications, Environ. Geochem. Health, 33 (2011) 267–278.
  83. A. Mesdaghinia, K.A. Vaghefi, A. Montazeri, M.R. Mohebbi, R. Saeedi, Monitoring of fluoride in groundwater resources of Iran, Bull. Environ. Contam. Toxicol., 84 (2010) 432–437.
  84. M.H. Matloob, Fluoride concentration of drinking water in Babil, Iraq, J. Appl. Sci., 11 (2011) 3315–3321.
  85. K. AbuZeid, L. El-Hatow, Impact of fluoride content in drinking water [online]. Available at http://web.cedare.org/wp-content/uploads/2005/05/Impact-of-fluoride content-in-drinking water-by-Khaled-Abu-Zeid-and-Lama-El-Hatow.pdf, 2005.
  86. E.S. Akpata, J. Behbehani, J. Akbar, L. Thalib, O. Mojiminiyi, Fluoride intake from fluids and urinary fluoride excretion by young children in Kuwait: a non-fluoridated community, Community Dent. Oral Epidemiol., 42 (2014) 224–233.
  87. Palestine: Palestine standard 41, Palestine standards Institutions [online], 1997.
  88. A.M. Aldosari, E.S. Akpata, N. Khan, A.H. Wyne, A. Al-Meheithif, Fluoride levels in drinking water in the central province of Saudi Arabia, Ann. Saudi Med., 23 (2002) 20–23.
  89. N. Oruc, Occurrence and problems of high fluoride waters in Turkey: An overview, Environ. Geochem. Health, 30 (2008) 315–323.
  90. T. Walia, S.A. Fanas, M. Akbar, J. Eddin, M. Adnan, Estimation of fluoride concentration in drinking water and common beverages in United Arab Emirates (UAE), The Saudi Dental J., 29 (2017)117–122.
  91. K. Sekkoum, M.F. Talhi, A. Cheriti, Y. Bourmita, N. Belboukhari, N. Boulenouar, S. Taleb, Water in Algerian Sahara: environmental and health impact. In: Ning, R.Y. (Ed.), Advancing Desalination. InTech, Croatia, pp. 197–216 (2012).
  92. W.Y. Fantong, H. Satake, S.N. Ayonghe, E.C. Suh, S.M. Adelana, E.B.S. Fantong, H.S. Banseka, C.D. Gwanfogbe, L.N. Woincham, Y. Uehara, J. Zhang, Geochemical provenance and spatial distribution of fluoride in groundwater of Mayo Tsanaga River basin, far North Region, Cameroon: implications for incidence of fluorosis and optimal consumption dose, Environ. Geochem. Health, 32 (2010) 147–163.
  93. M.A. Saleh, E. Ewane, J. Jones, B.L. Wilson, Chemical evaluation of commercial bottled drinking water from Egypt, J. Food Compos. Anal., 14 (2001) 127–152.
  94. T. Ayenew, The distribution and hydrogeological controls of fluoride in the groundwater of Central Ethiopian rift and adjacent highlands, Environ. Geol., 54 (2008) 1313–1324.
  95. Y.S. Anku, B. Banoeng-Yakubo, D.K. Asiedu, S.M. Yidana, Water quality analysis of groundwater in crystalline basement rocks, Northern Ghana, Environ. Geol., 58 (2009) 989–997.
  96. E.W. Wambu, G.K. Muthakia, High fluoride water in the Gilgil area of Nakuru County, Kenya, Fluoride, 44 (2011) 37.
  97. K.W.M. Msonda, W.R.L. Masamba, E. Fabiano, A study of fluoride groundwater occurrence in Nathenje, Lilongwe, Malawi, Phys. Chem. Earth, 32 (2007) 1178–1184.
  98. R. El-Jaoudi, F. Mamouch, M.A. El-Cadi, Y. Bousliman, Y. Cherrah, A. Bouklouze, Determination of fluoride in tap water in Morocco using a direct electrochemical method, Bull. Environ. Contam. Toxicol., 89 (2012) 390–394.
  99. S. Arji, Hundreds of Children Poisoned by Tap Water [online]. Available at http://www.fluoridealert.org/news/hundredsof-children-poisoned-by-tap-water, 2001.
  100. E.S. Akpata, I.S. Danfillo, E.C. Otoh, J.O. Mafeni, Geographical mapping of fluoride levels in drinking water sources in Nigeria, Afr. Health Sci., 9 (2009) 227–233.
  101. C.H. Kane, M. Diene, M. Fall, B. Sarr, A. Thiam, Reassessment of the resources of a deep aquifer system under physical and chemical constraints: the Maastrichtian aquifer, J. Water. Resour. Prot., 4 (2012) 217–223.
  102. A.M. Abdellah, H.M. Abdel-Magid, N.A. Yahia, Effect of longterm pumping on fluoride concentration levels in groundwater: a case study from east of Blue Nile communities of Sudan, J. Appl. Sci., 12 (2012) 1345–1354.
  103. J. Haarhoff, The accuracy of fluoride measurement in water and its implications for water fluoridation, Water SA, 29 (2003) 219–224.
  104. B. Thole, Ground water contamination with fluoride and potential fluoride removal technologies for East and Southern Africa. In: Ahmad, I., Dar, M.A. (Eds.), Perspectives in Water Pollution. InTech, 65–95 (2013).
  105. A.B. Nasr, K. Walha, C. Charcosset, R.B. Amar, Removal of fluoride ions using cuttlefish bones, J. Fluor. Chem., 132 (2011) 57–62.
  106. C.M. Rwenyonyi, J.M. Birkeland, O. Haugejorden, K. Bjorvatn, Age as a determinant of severity of dental fluorosis in children residing in areas with 0.5 and 2.5 mg fluoride per liter in drinking water, Clin. Oral Investig., 4 (2000) 157–161.
  107. http://arkisto.gtk.fi/abs/tr149abssu.htm.
  108. A. Queste, M. Lacombe, W. Hellmeier, F. Hillermann, B. Bortulussi, M. Kaup, K. Ott, W. Mathys, High concentrations of fluoride and boron in drinking water wells in the Muenster region — results of a preliminary investigation, Int. J. Hyg. Environ. Health, 203 (2001) 221–224.
  109. Fluoridation of Water Supplies Regulations: Irish Statute Book [online] Available at http://www.rsc.org/periodic-table/element/9/fluorine, 2007.
  110. W. D’Alessandro, S. Bellomo, F. Parello, L. Brusca, M. Longo, Survey on fluoride, bromide and chloride contents in public drinking water supplies in Sicily (Italy), Environ. Monit. Assess., 145 (2008) 303–313.
  111. A. Bardsen, K. Bjorvatn, K. Sand, D. Banks, Seasonal variations of fluoride content in groundwater from wells drilled in bedrock, Ngu-Bull, 435 (1999) 53–58.
  112. W. Czarnowski, K. Wrześniowska, J. Krechniak, Fluoride in drinking water and human urine in Northern and Central Poland. Sci. Total Environ., 191 (1996) 177–184.
  113. A. Hardisson, M.I. Rodríguez, A. Burgos, L.D. Flores, R. Gutiérrez, H. Várela, Fluoride levels in publicly supplied and bottled drinking water in the island of Tenerife, Spain, Bull. Environ. Contam. Toxicol., 67 (2001) 163–170.
  114. A. Augustsson, T. Berger, Assessing the risk of an excess fluoride intake among Swedish children in households with private wells — expanding static single-source methods to a probabilistic multi-exposure-pathway approach, Environ. Int., 68 (2014) 192–199.
  115. C. González-Horta, L. Ballinas-Casarrubias, B. Sánchez-Ramírez, M.C. Ishida, A. Barrera-Hernández, D. Gutiérrez-Torres, O.L. Zacarias, R.J. Saunders, Z. Drobná, M.A. Mendez, G. García-Vargas, A concurrent exposure to arsenic and fluoride from drinking water in Chihuahua, Mexico, Int. J. Environ. Res. Pub. Health, 12 (2015) 4587–4601.
  116. L.A. Senior, R.A. Sloto, Arsenic, boron, and fluoride concentrations in groundwater in and near diabase intrusions, Newark Basin, Southeastern Pennsylvania. In: Scientific Investigation Report, 2006–5261. US Department of the interior, USGS (2006)
  117. N. Mirlean, A. Roisenberg, Fluoride distribution in the environment along the gradient of a phosphate-fertilizer production emission (Southern Brazil), Environ. Geochem. Health, 29 (2007) 179–187.
  118. E.E. Buchhamer, P.S. Blanes, R.M. Osicka, M.C. Giménez, Environmental risk assessment of arsenic and fluoride in the Chaco Province, Argentina: research advances, J. Toxicol. Environ. Health Part A., 75 (2012) 1437–1450.
  119. Fluoride Review Guidelines: Outcomes of Fluoride Consensus Workshop Australian Research Centre for Population Oral Health [online], 2012.
  120. G.E. Smith, Fluoride and fluoridation, Soc. Sci. Med., 26 (1988) 451–462.
  121. S.F. Yang, G.W. Miller, Biochemical studies on the effect of fluoride on higher plants: Metabolism of carbohydrates, organic acids and amino acids, Biochem. J., 88 (1963) 505–509.
  122. P. Mondal, S. George, Removal of fluoride from drinking water using novel adsorbent magnesia-hydroxyapatite, Water Air Soil Poll., 226 (2015) 241.
  123. J.M. Neuhold, W.F. Siegler, Effects of sodium fluoride on carp and rainbow trout, Trans. Am. Fish Sot., 89 (1960) 358–370.
  124. D.A. Greenwood, Some effects of inorganic fluoride on plants, animals, and man. Available at https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=1039&context=honor_lectures, 1960.
  125. A.L. Choi, G. Sun, Y. Zhang, G. Philippe, Developmental fluoride neurotoxicity: A systematic review and meta-analysis, Environ. Health Perspect., 120 (2012) 1362–1368.
  126. M.K. Uddin, R. Bushra, Synthesis and characterization of composite cation-exchange material and its application in removing toxic pollutants. In: Anjum N, Gill S, Tuteja N (eds) Enhancing Cleanup of Environmental Pollutants, Vol. 2: Non-Biological Approaches, Springer, Cham, 2017, pp. 297–311.
  127. M.K. Uddin, P.F. Rahaman, A study on the potential applications of rice husk derivatives as useful adsorptive material. In: Inamuddin, Mohammad A, Asiri AM (eds) Inorganic Pollutants in Wastewater. Methods of Analysis, Removal and Treatment, Materials Research Forum LLC, 2017, pp. 149–186.
  128. M.A. Khan, M.K. Uddin, R. Bushra, A. Ahmad, S.A. Nabi, Synthesis and characterization of polyaniline Zr (IV) molybdophosphate for the adsorption of phenol from aqueous solution, React. Kinet. Mech. Cat., 113 (2014) 499–517.
  129. R.A.K. Rao, M. Kashifuddin, Kinetics and isotherm studies of Cd (II) adsorption from aqueous solution utilizing seeds of bottlebrush plant (Callistemon chisholmii), Appl. Water Sci., 4 (2014) 371–383.
  130. R.A.K. Rao, F. Rehman, M. Kashifuddin, Removal of Cr (VI) from electroplating wastewater using fruit peel of leechi (Litchi chinensis), Desal. Water Treat., 49 (2012) 136–146.
  131. R.A.K. Rao, S. Ikram, M.K. Uddin, Removal of Cd (II) from aqueous solution by exploring the biosorption characteristics of Gaozaban (Onosmabracteatum), J. Environ. Chem. Eng., 2 (2014) 1155–1164.
  132. Y. Sun, Q. Fang, J. Dong, X. Cheng, J. Xu, Removal of fluoride from drinking water by natural stilbite zeolite modified with Fe(III), Desalination, 277 (2011) 121–127.
  133. Q. Guo, E.J. Reardon, Fluoride removal from water by meixnerite and its calcination product, Appl. Clay Sci., 56 (2012) 7–15.
  134. D. Dayananda, V.R. Sarva, S.V. Prasad, J. Arunachalam, N.G. Narendra, Preparation of CaO loaded mesoporous Al2O3: efficient adsorbent for fluoride removal from water, Chem. Eng. J., 248 (2014) 430–439.
  135. M. Dessalegne, F. Zewge, I. Diaz, Aluminum hydroxide supported on zeolites for fluoride removal from drinking water, J. Chem. Tech. Biotech., 92 (2017) 605–613.
  136. D. Mehta, P. Mondal, S. George, Utilization of marble waste powder as a novel adsorbent for removal of fluoride ions from aqueous solution, J. Environ. Chem. Eng., 4 (2016) 932–942.
  137. Q. Liu, H. Guo, Y. Shan, Adsorption of fluoride on synthetic siderite from aqueous solution, J. Fluor. Chem., 131 (2010) 635–641.
  138. D. Thakre, S. Rayalu, R. Kawade, S. Meshram, J. Subrt, N. Labhsetwar, Magnesium incorporated bentonite clay for defluoridation of drinking water, J. Hazard. Mater., 180 (2010) 122–130.
  139. P. Mondal, D. Mehta, S. George, Defluoridation studies with synthesized magnesium-incorporated hydroxyapatite and parameter optimization using response surface methodology, Desal. Water Treat., 57 (2016) 27294–27313.
  140. S. Alemu, E. Mulugeta, F. Zewge, B.S. Chandravanshi, Water defluoridation by aluminium oxide–manganese oxide composite material, Environ. Technol., 35 (2014) 1893–1903.
  141. M.R. Ghosh, S.P. Mishra, Effect of Co-ions on Cr(VI) and F−adsorption by thermally treated bauxite (TTB), Arab. J. Sci. Eng., 42 (2017) 4391–4400.
  142. V. Masindi, Application of cryptocrystalline magnesite-bentonite clay hybrid for defluoridation of underground water resources: implication for point of use treatment, J. Water Reuse Desal., 8 (2017) 338–352.
  143. W.M. Gitari, T. Ngulube, V. Masindi, J.R. Gumbo, Defluoridation of groundwater using Fe3+ modified bentonite clay: optimization of adsorption conditions, Desal. Water Treat., 53 (2015) 1578–1590.
  144. V.K. Rathore, D.K. Dohare, P. Mondal, Competitive adsorption between arsenic and fluoride from binary mixture on chemically treated laterite, J. Environ. Chem. Eng., 4 (2016) 2417–2430.
  145. R. Mudzielwana, M.W. Gitari, T.A.M. Msagati, Characterisation of smectite-rich clay soil: implication for groundwater defluoridation, South Afr. J. Sci., 112 (2016) 1–8.
  146. S. Yue, G. Huaming, Fluoride adsorption on modified natural siderite: optimization and performance, Chem. Eng. J., 223 (2013) 183–191.
  147. A.A. Izuagie, W.M. Gitari, J.R. Gumbo, Defluoridation of groundwater using diatomaceous earth: optimization of adsorption conditions, kinetics and leached metals risk assessment, Desal. Water Treat., 57 (2016) 16745–16757.
  148. A. Dhillon, S.K. Soni, D. Kumar, Enhanced fluoride removal performance by Ce–Zn binary metal oxide: adsorption characteristics and mechanism, J. Fluor. Chem., 199 (2017) 67–76.
  149. P.S. Ghosal, A.K. Gupta, Enhanced efficiency of ANN using non-linear regression for modeling adsorptive removal of fluoride by calcined Ca-Al-(NO3)-LDH, J. Mol. Liq., 222 (2016) 564–570.
  150. H. Wang, Q. Feng, K. Liu, Z. Li, X. Tang, G. Li, Highly efficient fluoride adsorption from aqueous solution by nepheline prepared from kaolinite through alkali-hydrothermal process, J. Environ. Manage., 196 (2017) 72–79.
  151. M.N. Sepehr, H. Kazemian, E. Ghahramani, A. Amrane, V. Sivasankar, M. Zarrabi, Defluoridation of water via light weight expanded clay aggregate (LECA): Adsorbent characterization, competing ions, chemical regeneration, equilibrium and kinetic modeling, J. Taiwan Inst. Chem. Eng., 45 (2014) 1821–1834.
  152. N.T. Hue, N.H. Tung, Study about doping ion La3+ onto surface of pyrolusite ore for removing simultaneously both fluoride and phosphate from wastewater, J. Chem., 2017 (2017) 1–11.
  153. R. Mudzielwana, M.W. Gitari, S.A. Akinyemi, T.A.M. Msagati, Synthesis and physicochemical characterization of MnO2 coated Na-bentonite for groundwater defluoridation: adsorption modelling and mechanistic aspect, Appl. Surface Sci., 422 (2017) 745–753.
  154. C. Prathibha, B. Sharma, L.A.A. Chunduri, S.K. Aditha, T.M. Rattan, K. Venkataramaniah, Nano calcium-aluminum mixed oxide: a novel and effective material for defluoridation of drinking water, Sep. Sci. Technol., 50 (2015) 1915–1924.
  155. S. Roy, P. Das, S. Sengupta, Thermodynamics and kinetics study of defluoridationusing Ca-SiO2-TiO2 as adsorbent: column studies and statistical approach, Korean J. Chem. Eng., 34 (2017) 179–188.
  156. W. Xiang, G. Zhang, Y. Zhang, D. Tang, J. Wang, Synthesis and characterization of cotton-like Ca–Al–La composite as an adsorbent for fluoride removal, Chem. Eng. J., 250 (2014) 423–430.
  157. S. Gammoudi, N. Frini-Srasra, E. Srasra, Preparation, characterization of organo smectites and fluoride ion removal, Inter. J. Mine. Process., 125 (2013) 10–17.
  158. L. Wu, G. Zhang, D. Tang, A novel high efficient Mg–Ce–La adsorbent for fluoride removal: kinetics, thermodynamics and reusability, Desal. Water Treat., 57 (2016) 23844–23855.
  159. J.H. Kim, C.G. Lee, J.A. Park, J.K Kang, N.C. Choi, S.B. Kim, Use of pyrophyllite clay for fluoride removal from aqueous solution, Desal. Water Treat., 51 (2013) 16–18.
  160. S. Mandal, S. Tripathy, T. Padhi, M.K. Sahu, R.K. Patel, Removal efficiency of fluoride by novel Mg-Cr-Cl layered double hydroxide by batch process from water, J. Environ. Sci., 25 (2013) 993–1000.
  161. E. Kır, H. Oruc, I. Kır, T. Sardohan-Koseoglu, Removal of fluoride from aqueous solution by natural and acid-activated diatomite and ignimbrite materials, Desal. Water Treat., 57 (2016) 21944–21956.
  162. V. Chaudhary, S. Prasad, Rapid removal of fluoride from aqueous media using activated dolomite, Anal. Methods, 7 (2015) 8304.
  163. L. Li, Q. Zhu, K. Man, Z. Xing, Fluoride removal from liquid phase by Fe-Al-La trimetalhydroxides adsorbent prepared by iron and aluminum leaching from red mud, J. Mol. Liq., 237 (2017) 164–172.
  164. T.Y. Datsko, V.I. Zelentsov, Fluorine sorption by alumino-silicate-modified diatomite from highly concentrated fluorine solutions: 1. Adsorption equilibrium, Surface Eng. Appl. Electrochem., 52 (2016) 300–311.
  165. N. Chen, Z. Zhang, C. Feng, D. Zhub, Y. Yang, N. Sugiura, Preparation and characterization of porous granular ceramic containing dispersed aluminum and iron oxides as adsorbents for fluoride removal from aqueous solution, J. Hazard. Mater., 186 (2011) 863–868.
  166. G.P. Kofa, V.H. Gomdje, C. Telegan, S. NdiKoungou, Removal of fluoride from water by adsorption onto fired clay pots: kinetics and equilibrium studies, J. Appl. Chem., 2017 (2017) 1–7.
  167. B. Ekka, R.S. Dhaka, R.K. Patel, P. Dash, Fluoride removal in waters using ionic liquid-functionalized alumina as a novel adsorbent, J. Cleaner Prod., 151 (2017) 303–318.
  168. S. Hamamoto, N. Kishimoto, M. Ueki, Mechanistic consideration of fluoride removal using aluminum sulfate, J. Water Environ. Tech., 13 (2015) 15–24.
  169. S. Zhang, Y. Lyu, X. Su, Y. Bian, B. Yu, Y. Zhang, Removal of fluoride ion from groundwater by adsorption on lanthanum and aluminum loaded clay adsorbent, Environ. Earth Sci., 75 (2016) 401.
  170. J. Saikia, S. Sarmah, H.A. Tobiul, P.J. Kalita, R.L. Goswamee, Removal of toxic fluoride ion from water using low cost ceramic nodules prepared from some locally available raw materials of Assam, India, J. Environ. Chem. Eng., 5 (2017) 2488–2497.
  171. J.J. García-Sánchez, M. Solache-Ríos, J.M. Martínez-Gutiérrez, N.V. Arteaga-Larios, M.C. Ojeda-Escamilla, I. Rodríguez-Torres, Modified natural magnetite with Al and La ions for the adsorption of fluoride ions from aqueous solutions, J. Fluor. Chem., 186 (2016) 115–124.
  172. A. Maiti, J.K. Basu, S. De, Chemical treated laterite as promising fluoride adsorbent for aqueous system and kinetic modeling, Desalination, 265 (2011) 28–36.
  173. S.M. Prabhu, S. Meenakshi, Synthesis of surface coated hydroxyapatite powders for fluoride removal from aqueous solution, Powder Technol., 268 (2014) 306–315.
  174. T. Ngulube, M.W. Gitari, H. Tutu, Defluoridation of groundwater using mixed Mukondeni clay soils, Wat. Sci. Tech., 17 (2016) 480–492.
  175. T.O. Ologundudu, J.O. Odiyo, G.E.I. Ekosse, Fluoride sorption efficiency of vermiculite; functionalised with cationic surfactant: isotherm and kinetics, Appl. Sci., 6 (2016) 277.
  176. S. Wu, K. Zhang, J. He, X. Cai, K. Chen, Y. Li, B. Sun, L. Kong, J. Liu, High efficient removal of fluoride from aqueous solution by a novel hydroxyl aluminum oxalate adsorbent, J. Colloid Interface Sci., 464 (2016) 238–245.
  177. N. Chen, Z. Zhang, C. Feng, N. Sugiura, M. Li, R. Chen, Fluoride removal from water by granular ceramic adsorption, J. Colloid Interface Sci., 348 (2010) 579–584.
  178. M. Nazari, R. Halladj, Adsorptive removal of fluoride ions from aqueous solution by using sonochemically synthesized nanomagnesia/alumina adsorbents: an experimental and modeling study, J. Taiwan Inst. Chem. Eng., 45 (2014) 2518–2525.
  179. A. Dhillon, Sapna, D. Kumar, Dual adsorption behaviour of fluoride from drinking water on Ca-Zn(OH)2CO3 adsorbent, Surf. Interf., 6 (2017)154–161.
  180. Y. Lyu, X., Su, S., Zhang, Y. Zhang, Preparation and characterization of La(III)-Al(III) Co-loaded hydrothermal palygorskite adsorbent for fluoride removal from groundwater, Water Air Soil Pollut., 227 (2016) 454.
  181. A. Teimouri, S.G. Nasab, S. Habibollahi, M. Fazel-Najafabadi, A.N. Chermahini, Synthesis and characterization of a chitosan/montmorillonite/ZrO2 nanocomposite and its application as an adsorbent for removal of fluoride, RSC Adv., 5 (2015) 6771.
  182. M. Wang, X. Yu, C. Yang, X. Yang, M. Lin, L. Guan, M. Ge, Removal of fluoride from aqueous solution by Mg-Al-Zr triple-metal composite, Chem. Eng. J., 322 (2017) 246–253.
  183. D, Wan, Y. Liu, S. Xiao, J. Chen, J. Zhang, Uptake fluoride from water by caclined Mg-Al-CO3 hydrotalcite: Mg/Al ratio effect on its structure, electrical affinity and adsorptive property, Colloids Surf. A: Physicochem. Eng. Asp., 469 (2015) 307–314.
  184. T. Li, D. Xie, C. He, X. Xu, B. Huang, R. Nie, S. Liu, Z. Duan, W. Liu, Simultaneous adsorption of fluoride and hexavalent chromium by synthetic mesoporous alumina: performance and interaction mechanism, RSC Adv., 6 (2016) 48610–48619.
  185. M. Karthikeyan, K.K. Kumar, K.P. Elango, Studies on the defluoridation of water using conducting polymer/montmorillonite composites, Environ. Techn., 33 (2012) 733–739.
  186. W. Yang, S. Tian, Q. Tang, L. Chai, H. Wang, Fungus hyphae-supported alumina: An efficient and reclaimable adsorbent for fluoride removal from water, J. Colloid Interface Sci., 496 (2017) 496–504.
  187. I. Langmuir, The constitution and fundamental properties of solids and liquids, J. Am. Chem. Soc., 38 (1916) 2221–2295.
  188. H.M.F. Freundlich, Over the adsorption in solution, J. Phys. Chem., 57 (1906) 385–470.
  189. M. Vhahangwele, G.W. Mugera, N. Tholiso, Defluoridation of drinking water using Al3+– modified bentonite clay: optimization of fluoride adsorption conditions, Toxicol. Environ. Chem., 96 (2014) 1294–1309.
  190. G. Lee, C. Chen, S.T. Yang, W.S. Ahn, Enhanced adsorptive removal of fluoride using mesoporous alumina, Micropor. Mesopor. Mat., 127 (2010) 152–156.
  191. A. Salifu, B. Petrusevski, E.S. Mwampashi, I.A. Pazi, K. Ghebremichael, R. Buamah, C. Aubry, G.L. Amy, M.D. Kenedy, Defluoridation of groundwater using aluminum-coated bauxite: optimization of synthesis process conditions and equilibrium study, J. Environ. Manage., 181 (2016) 108–117.
  192. Y. Yu, J.P. Chen, Fabrication and performance of a Mn–La metal composite for remarkable decontamination of fluoride, J. Mater. Chem. A, 2 (2014) 8086–8093.
  193. T. Zhang, H. Yu, Y. Zhou, J. Rong, Z. Mei, F. Qiu, Enhanced adsorption of fluoride from aqueous solutions by hierarchically structured Mg-Al LDHs/Al2O3 composites, Korean J. Chem. Eng., 33 (2016) 720–725.
  194. A. Quintáns-Fondo, G. Ferreira-Coelho, R. Paradelo-Núñez, J.C. Nóvoa-Muñoz, M. Arias-Estévez, M.J. Fernández-Sanjurjo, E. Álvarez-Rodríguez, A. Núñez-Delgado, F Sorption/desorption on two soils and on different by-products and waste materials, Environ. Sci. Pollut. Res., 23 (2016) 14676–14685.
  195. S. Wei, X. Yang, W. Xiang, Preparation and adsorption properties for fluoride of kaolinite-magnetite association. Proc. 2011 International Conference on Electronics and Optoelectronics [online] Available at https://ieeexplore.ieee.org/document/6013133/, 2011.
  196. G. Lv, L. Wu, L. Liao, Y. Zhang, Z. Li, Preparation and characterization of red mud sintered porous materials for water defluoridation, Appl. Clay Sci., 74 (2013) 95–101.
  197. Z. Yong-Xing, J. Yong, Fluoride adsorption onto amorphous aluminum hydroxide: roles of the surface acetate anions, J. Colloid Interface Sci., 483 (2016) 295–306.
  198. Y. Nie, C. Hu, C. Kong, Enhanced fluoride adsorption using Al (III) modified calcium hydroxyapatite, J. Hazard Mater., 233–234 (2012) 194– 199.
  199. S. Roy, S. Sengupta, P. Das, Integral approach of adsorption and chemical treatment of fluoride containing wastewater: batch and optimization using RSM, J. Environ. Chem. Eng., 5 (2017) 274–282.
  200. S. Lagergren, About the theory of so-called adsorption of soluble substances, Kung. Sven. Vetensk. Ademiens. Handl., 24 (1898) 1–39.
  201. Y.S. Ho, G. Mckay. The kinetics of sorption of divalent metal ions onto sphagnum moss peat, Water Res., 34 (2000) 735–742.
  202. W.J. Weber, J.C. Morris, Kinetics of adsorption on carbon from solution, J. Sanit. Eng. Div. Am. Soc. Civ. Eng., 89 (1963) 1–60.