Abstract

Background: Pharmaceuticals, endocrine-disrupting chemicals (EDCs), per- and polyfluoroalkyl substances (PFAS) and micro plastics, together with personal care items, are increasingly found in the water bodies. These compounds tend to be resistant to the traditional water and wastewater treatment methods since they are persistent, low in concentrations, and possess varying physicochemical characteristics. The fact that they still remain in treated effluent is a great concern to human health and ecological integrity. Objective: The purpose of the review is to critically analyze the existing limitations of EC removal with the available treatment technologies, determine the working of advanced and hybrid systems, and develop a risk-based approach in the integration of the removal efficiency and the protection of the populace and the environment. Methods: The systematic review approach was utilized with the use of Scopus, Web of Science, PubMed, and ScienceDirect literature. Inclusion criteria were peer-reviewed articles that discussed EC occurrence, treatment performance and risk assessment. The analysis was an integration of comparative analysis of removal efficiencies with toxicological indices, including bioaccumulation, pathways of exposure, and persistence. Results: The traditional treatment systems had low EC removal (under 40 percent), especially with persistent and hydrophilic compounds. The removal rates of advanced oxidation processes (AOPs), membrane filtration and adsorption were 60-99 % depending on EC class. The hybrid systems were also superior to single technologies, but they experienced issues concerning the cost, integration, and scalability. Another common gap that was found in the review was the lack of correlation between the effectiveness of the treatment and reduction of health risks. Implications: Results highlight the importance of multi-barrier treatment approaches that are integrated and combine the objectives of technical performance with the objectives of risk mitigation. The paper offers advice to engineers, regulators and policymakers to promote the practices and regulatory standards of water treatment in response to the emergent chemical threats.