A Review About the Occurrence and Effectiveness of Conventional and Advanced Treatment Technologies of Persistent Organic Pollutants in Surface Water

Persistent organic pollutants (POPs) refer to various pollutants, including organochlorine pesticides (OCPs), industrial chemicals, and other unintended byproducts that are discharged through anthropogenic activities such as industrial processes, waste disposal, and agricultural activities, as well as natural sources such as forest fires and volcanic eruptions. POPs have the potential to harm ecosystems and humans due to their toxicity, high environmental persistence, global emissions, and bioaccumulation. Despite the significant progress in various treatment technologies for removing POPs in the previous literature, a report containing comprehensive information on the current effective treatment methods is lacking. In this study, the main mechanisms, key factors, and comparison of the performances between conventional and advanced methods for removing POPs are discussed. Moreover, the practical application of integration treatment systems in POPs removal is also analyzed, providing lessons and prospects for further research. The review results show that most POPs occur in surface water around the world and that some of them have been found in drinking water treatment systems. The adsorption process is one of the best options among conventional methods, achieving a high removal efficiency of POPs from surface water. Advanced oxidation processes (AOPs) such as O3/UV, fenton, and photofenton are suitable methods for eliminating POPs in surface water because of their high removal efficiency, easy operation, and integration into existing facilities. Despite having some limitations, such as being high cost and requiring highly skilled maintenance, NF and RO membranes have a high potential for application in removing POPs and other pollutants from surface water, especially drinking water treatment systems. In addition, the practical application of integration treatment systems has also been proven effective at eliminating POPs in large-scale systems. Therefore, an overview of these methods for treating POPs in surface water will enable a better understanding of the removal mechanisms, efficiency, and applications available in practice.