Advanced oxidation processes for the treatment of contaminants of emerging concern

The application of contaminants of emerging concern (CECs) such as pharmaceuticals and personal care products, pesticides, flame retardants, plasticizers, endocrine disruptors, surfactants, and polycyclic aromatic hydrocarbons (PAHs) became an indispensable requirement of the current era. Although the CECs are useful for wide-spectrum purposes, they can also result in undesirable effects on human health and other animals. The large-scale use of CEC leads to their ubiquitous occurrence in surface and ground water sources and has caused great concern among the scientific community and regulatory authorities in recent years. Because CEC may have significant adverse effects on human health and other animals including aquatic life, their efficient removal from waterbodies is essential. A number of advanced oxidation processes (AOPs) have been established for the enhanced degradation of CEC. This book chapter focuses on the occurrence and possible effects of CEC on human health and other animals. Various AOPs have been discussed in detail and their applications for the treatment of CEC have been outlined. The AOPs were divided into three groups namely chemical, photochemical, and photocatalytic AOPs. Both hydroxyl and sulfate radicals-driven AOPs were discussed. The experimental results of previously published research papers regarding the removal of CEC have been summarized under each AOP section for better understanding of the effectiveness of these AOPs. The various factors that could affect the performance of these AOPs were taken into account. Furthermore, the cost evaluation of different AOPs is summarized. At the end, some challenges faced by AOPs, including the formation of toxic disinfection by-products, have been highlighted. Finally, future suggestions are recommended for practical applications of these AOPs.