A Review of Sources, Worldwide Legislative Measures and the Factors Influencing the Treatment Technologies for Contaminants of Emerging Concern (CECs)

• Published in: Current pollution reports Vol. 11; no. 1; p. 44
• Main Authors: Harish, Harini, Jegatheesan, Veeriah
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 27.06.2025; Springer Nature B.V
• Subjects: Activated carbon; Activated carbon adsorption; Analgesics; Antibiotics; Antidiabetics; Aquatic environment; Aquatic Pollution; Artificial wetlands; Atmospheric Protection/Air Quality Control/Air Pollution; Biodegradation; Chemicals; Comparative studies; Consumer products; Contaminants; Corrosion inhibitors; Cost effectiveness; Developing countries; Drinking water; Drug resistance; Earth and Environmental Science; Endocrine disruptors; Environment; Environmental Law/Policy/Ecojustice; Environmental protection; Enzymes; Flame retardants; Food contamination & poisoning; Heavy metals; Herbicides; Hormones; Hydrology; Industrial Pollution Prevention; Insecticides; LDCs; Maintenance costs; Membrane filtration; Metabolites; Microbial activity; Microbial contamination; Microorganisms; Monitoring/Environmental Analysis; Organic compounds; Organic matter; Oxidation; Pesticides; Pharmaceuticals; Photodegradation; Phytoremediation; Pollutant removal; Pollutants; Pollution; Pollution control; Polycyclic aromatic hydrocarbons; Public health; R&D; Research & development; Review; Stormwater; Stormwater management; Surfactants; Topical Collection on Water and Sediment Pollution; Urban runoff; Urbanization; Waste Water Technology; Wastewater treatment; Water Management; Water pollution; Water Pollution Control; Water quality; Water treatment; Contaminants of emerging concern (CECs); Legislations; Sources; Removal factors; Constructed wetlands (CW)
• ISSN: 2198-6592; 2198-6592
• DOI: 10.1007/s40726-025-00357-7

Purpose of the Review Controlling the transportation and removing contaminants of emerging concerns (CECs) from urban runoff is indeed a significant challenge for both developed and developing countries. Since most drinking water treatment systems are ineffective in removing these contaminants, addressing this issue requires a multi-faceted approach such as source identification, control using green infrastructure, advanced treatment technologies, public awareness and amending regulatory frameworks. Working towards that requires an in-depth understanding of the previous and ongoing research on categories of CECs, and new-age sustainable removal techniques that include nature-based removal systems (NBS). This paper aims to (1) identify and categorize the direct and indirect sources of CECs, (2) evaluate the effectiveness of existing legislative measures, (3) various CECs treatment/removal technologies and analyze the factors affecting treatment technologies, (4) highlight challenges and advancements and (5) propose recommendations for future research and policy development. Ultimately, this review aims to contribute to the development of more effective and sustainable strategies for managing CECs, ensuring better protection of environmental and public health.  Recent Findings The reviewed articles detail global efforts to eradicate CECs from the environment. These efforts include creating priority lists of chemicals that need to be removed, tailored to their usage in specific countries. For instance, Australia employs a tool called ECHIDNA, which aids in prioritizing and categorizing harmful chemicals that could disrupt the environment. After identifying these chemicals, various methods are then employed to treat water and remove the CECs effectively. NBS can be considered a sustainable yet efficient treatment solution for the removal of CECs from the urban stormwater sink. Constructed wetlands (CWs) are considered to be one of the most effective NBS for water treatment and CECs control in the aquatic environment. Key removal processes involved are sorption, photodegradation, microbial biodegradation and phytoremediation. Factors such as hydrology, substrate, vegetation, Log (Kow), structure of the CEC compounds, water polarity of the chemicals to be removed, presence of electron-donating groups and natural organic matter influence these removal mechanisms. A comparative study of various methods for eliminating CECs of various categories from water demonstrates that CWs are particularly notable, achieving an impressive 88% removal efficiency. This high efficiency, combined with their low operational and maintenance costs, makes them an attractive option for water treatment, in both developed and developing regions. CWs are highly effective in reducing pollution, with their cost-effectiveness being directly linked to their pollutant removal capabilities.  Summary Investing in the research and development of advanced treatment technologies specifically aimed at removing CECs from water is crucial for ensuring environmental and public health. Even though technologies such as advanced oxidation processes, membrane filtration and activated carbon adsorption show promising effectiveness in removing a wide range of contaminants, there are various NBS under study. CWs are considered promising NBSs that are more efficient and cost-effective in removing CECs. CW can degrade CECs, a combination of pesticides, personal care products (PCP), endocrine disruptor chemicals (EDC), pharmaceuticals, organic compounds such as polyaromatic hydrocarbons (PAHs) and disinfection by-products (DBP). CWs utilize natural processes involving plants, soil and associated microbial communities to treat contaminated water, making them a sustainable and eco-friendly option. This review paper aims to consolidate comprehensive information to enhance understanding of the current global perspective on CECs and highlights the challenges and advancements in managing CECs, ultimately contributing to the development of more effective and sustainable treatment solutions.