2. Fluoride Pollution in Subsurface Water: Challenges and Opportunities

Fluoride contamination in groundwater is one of the drinking water crisis globally. Although its presence is necessary in small quantities, it is harmful to humans with intakes of more than 1.5 mg L⁻¹ through contaminated drinking water due to geological factors and geochemical processes. A high fluoride content in drinking water results in skeletal fluorosis, as well as long-term liver, kidney, and brain damage. One of the most crucial challenges for drinking water safety is the management of fluoride pollution and fluorosis. To reduce the probability of fluorosis, it is essential to have a better understanding of the mechanisms underlying the presence of fluoride in the chemistry of subsurface water and the ability to identify high-risk locations using geographic data and remote sensing. The utilization of other sources of water or mixing should be prioritized. The development of stable technologies and integrated devices that are efficient, affordable, and manageable, as well as fundamental research on defluoridation reagents and novel materials, should receive significant amount of focus. To achieve stable gains, the design, construction, operation, and monitoring of defluoridation facilities should be thoroughly evaluated and improved. This chapter highlights the extent of fluoride contamination, the effect of fluoride contamination on human health, and the available defluoridation methods.