Water Disinfection: Background, Current Trends, Challenges, and Gaps

World’s population is growing rapidly and it will touch 10 million by the end of 2050. Availability of clean and safe water for all is a global challenge. Disinfection of water is the most important step in water treatment to ensure the inactivation of pathogens from water. There are many techniques/materials available for disinfection of water. However, there are also many challenges associated with successful implementation of methods of disinfection including cost, type of pathogens, and other health implications caused due to formation of disinfection byproducts during the disinfection process. In this chapter, the background of water disinfection techniques as well as recent trends of the area has been discussed in detail with an objective to suggest safer strategies for water disinfection. Disinfection by-products often lead to health implications due to their long-lasting and toxic behavior. There are many other factors including pH, residence period, temperature, natural organic matter, and other water characteristics that significantly affect the efficiency of disinfectants and fate of disinfection by-products. Some by-products are carcinogenic, reproductive toxicants as well as mutagenic in nature. However, with advancements in disinfection techniques formation of toxic by-products can be avoided during water treatment. These methods have been discussed in the chapter along with the challenges and knowledge gaps to provide a basic outlook for future research in the development of safer disinfection alternatives.