Bioremediation strategies for the treatment of Emerging Contaminants: a view from Phytoremediation

Introduction: Emerging Contaminants (ECs) are a broad and growing category of substances found in the environment, which have only recently been recognized as significant water pollutants. The inability of conventional wastewater treatment plants (WWTPs) to effectively remove ECs underscores the need for alternative, cost-effective, and environmentally friendly treatment methods. Objetive: The objective of this review is to explore bioremediation strategies for emerging contaminants (ECs) using constructed wetlands (CWs) and the role of plants in wastewater phytoremediation. We discuss ECs such as pharmaceuticals, personal care products, pesticides, hormones, perfluoroalkyl substances, and microplastics. Methodology: The methodology involved a bibliographic review using electronic databases from the Universidad del Valle Library, specifically SCOPUS and ScienceDirect (Elsevier). The search was conducted using keywords such as "Emerging Contaminants (ECs)," "Constructed Wetlands (CWs)," and "Tropical Plants in Phytoremediation" and publications from the last 3 years were prioritized. Results: The removal of ECs in CWs involves a complex interplay of physical, chemical, and biological processes, which are influenced by the design and operational parameters of the system. CWs vary significantly in design, with major configurations including surface flow (SF) and subsurface flow (SSF), as well as horizontal subsurface flow (HSSF) and vertical subsurface flow (VSSF) systems. These configurations differ in media type, depth, and overall treatment efficiency. Conclusions: This review examines the presence of ECs in aquatic environments and explores the use of plants in CWs as phytoremediation strategies. Findings indicate that CWs are a sustainable and effective alternative, with key removal mechanisms-including biodegradation, substrate adsorption, and macrophyte uptake-playing a crucial role in eliminating recalcitrant ECs. The design and operational conditions of CWs significantly impact phytoremediation efficiency.