Highlights
- Higher fluoride in drinking water is slow poison with irrecoverable consequences.
- The paper discusses the natural factors behind occurrences of high fluorosis globally.
- The Global Fluoride Belts are geographically connected and geologically similar with natural factors.
- In situ process of fluoride removal techniques, their removal capacity, advantages and disadvantages are discussed.
Abstract
Fluorosis is an endemic disease that is now a global challenge. In this review paper we have classified and described the global fluoride belts (GFB) geologically and geographically connecting different countries. A proper map of the global fluoride belts showing the inland connections between each belt is presented. Several natural factors like the rock type, soil, tectonics, hydrogeology and climate of a terrain which are majorly responsible for engrafting higher fluoride in drinking water are described. A detailed uniform description of each belts with respect to geology, geochemistry are discussed. The minor factors like altitude, phosphate mining etc. on fluorosis are also discussed including countries like Canada, Norway etc. which are potentially affected by fluorosis. The correlation of different ions like Cl?, Ca2+, etc; pH, electrical conductivity, TDS etc are compared and reviewed in detailed with respect to different GFB. The genesis and sources of fluoride contamination are also supported by different isotopic evidences. In this article, the in situ methods involving natural minerals and materials which can adsorb fluoride effectively and are being used globally are exhaustively assessed. The methods which are highly sustainable with minimum waste generation and cost effective are also evaluated.
*Original abstract online at https://www.sciencedirect.com/science/article/pii/S0022169419303658?via%3Dihub]=