Antibiotic Removal Based on Constructed Wetland: Mechanism, Performance, and Regulation

Antibiotics are widely distributed in aquatic environment and pose a potential risk to ecosystems at trace levels. Constructed wetlands (CWs) have been considered a sustainable and low-cost solution for pollutant removal. Therefore, the theme of antibiotic removal in constructed wetlands has become very important.

Many studies have reviewed the removal performance of antibiotics in different CWs. The properties of antibiotics (such as pKa, LogKow, and toxicity) are reported, which are not linked with their removal performance in different CWs. The dominant pathways for antibiotic removal in different CW configurations remain unknown. Removal of conventional pollutant and antibiotic in CWs are independently studied. The impacts of antibiotic involvement on conventional pollutant removal and changes in microbial communities in CWs need further investigation.

This review summarized the removal performance of commonly used antibiotics in different types of CWs and identified the specific types of antibiotics (i.e., β-lactams, macrolides, and sulfonamides) that are relatively difficult to remove. It systematically illustrated the mechanisms of essential CW components and their interactions on antibiotic removal. It also discussed the correlation between antibiotic properties and their removal efficiencies, indicating the dominant removal pathways in three CW types. Furtherly, this review analyzed the key operational factor regulation and CW structure modifications on antibiotic removal. Additionally, it concluded that antibiotics generally inhibited the removal of some traditional pollutants (excluding NH₄⁺-N) based on the data from current reports.