Fluoride Action Network



  • Overexposure to fluoride via drinking water causes several health effects including fluorosis
  • Endemic fluorosis is still persisted in several countries even with advancement in research
  • Most of fluorosis management techniques suggested in the past have come with their own drawbacks
  • Defluoridation techniques based on aluminium materials pose serious health risks to the public
  • A method which removes excess F- from drinking water without affecting water quality has a scope

Fluoride contamination in drinking water is a global issue. Frequent over-exposure to fluoride causes several health problems such as fluorosis, neurological, thyroid, osteoporosis, etc. The guideline values prescribed by the WHO and other nationals for fluoride in drinking water are reasonable but mostly relevant to fluorosis. However, these guideline values cannot be satisfied in some regions due to economic and financial shortcomings. Several fluorosis management techniques were suggested to address excess fluoride in drinking water, but each has specific drawbacks. Defluoridation techniques like the Nalgonda technique, reverse osmosis (RO), and adsorption using activated alumina have found to be promising to reduce fluoride concentration within the prescribed limits, and RO water is most widely used for drinking in fluorosis affected regions. However, these techniques are still associated with certain drawbacks, and prior research on this theme has focused on one dimension of removing excess fluoride from water. Hence, it is essential to understand the basic problems associated with fluoride contamination, such as sources of fluoride exposure, adverse health effects and defluoridation techniques feasibility. Furthermore, perception of the effect of co-existing ions with fluoride in drinking water is crucial in deciding fluoride toxicity level and developing efficient strategies for fluorosis mitigation.


Severe effects of fluoride on human health can be seen majorly in developing and underdeveloped countries. Among these countries, India is the most affected country, where there are many endemic fluorosis regions. India also has one of the largest fluorite deposits making its groundwater highly contaminated with fluoride. Most of the regions in Asia and Africa are prone to fluorosis based diseases. In Asia, India and China show the majority of cases. Whereas in the African continent, Tanzania is a popular region with a high concentration of fluoride in groundwater where it is a major source of drinking water (Shen et al., 2015; Ali et al., 2016). The Ethiopian rift valley has about 8 million people regularly over-exposed to natural fluoride present in groundwater (Rango et al., 2012; Demelash et al., 2019), while the East African rift valley has about ten times of that amount of people suffering from various fluorosis-related symptoms (Shen et al., 2015). China has approximately 21 million people affected with fluorosis and close to 10 million people suffering from skeletal fluorosis (Li et al., 2020). Fluorosis has affected around 3000 villages in China, most of which are located in arid and semi-arid island basins. Some of the major reasons for fluorosis cases are high fluoride contaminated groundwater, excess coal burning, and brick tea (Kimambo et al., 2019). In Mexico, approximately 20 million people consume water with 1.5 mg/L of fluoride and around 9,00,000 are exposed to even higher (4.5 – 29.6 mg/L) concentration of fluoride (Alarco?n-Herrera et al., 2020). Argentina, in the south American continent, is the most affected where the La Pampa region has fluoride concentrations as high as 25.7 mg/L in ground water (Smedley et al., 2002; Ali et al., 2016; Alcaine et al., 2020). Some of the European regions such as Spain and Norway have reported excess fluoride in their groundwaters, and cases of fluorosis related disorders are not severe (Kimambo et al., 2019). It is said that water fluoridation is practised in some countries in Europe due to the lack of natural fluoride; however, it is considered as controversial public health intervention, and its benefits and harms have been debated since its proposal (Peckham and Awofeso, 2014). In the USA, some regions of Arizona have reported fluoride concentrations > 4 mg/L in deep wells (McMahon et al., 2020).

… We also observed that there was no quantifiable data on groundwater fluoride levels in several areas regions in Russia, Australia, North Korea, etc. …