Enhancing Microbial Biodegradation of PPCPs in Wastewater via Natural Self-Purification in a Novel Constructed Wetland System

Pharmaceuticals and personal care products (PPCPs) are emerging contaminants posing ecological risks in wastewater. Constructed wetlands (CWs) offer sustainable treatment through integrated biological processes. In this study, a biomimetic microbial CW reactor was developed using 30 L aquariums with porous media, aeration setups, and surface plants to simulate natural wetland conditions. This design combines enhanced microbial degradation strategies using fungal (Trametes versicolor), bacterial (Pseudomonas aeruginosa), and consortia degradation, integrating multiple biological pathways. Synthetic wastewater containing 100 mg/L of selected PPCPs, including caffeine, methylparaben, and trichlorocarbanilide (TCC), was used to evaluate the degradation potential of these microbial treatments. While caffeine and methylparaben were effectively targeted, TCC degradation was inconclusive due to solubility limitations in the selected solvent. Over three months, system stability, plant growth, and microbial biomass were monitored, and contaminant degradation was tracked using Nuclear Magnetic Resonance analysis. Results demonstrated that individual fungal and bacterial treatments achieved near-complete caffeine degradation (99–100%) within seven weeks, while the combined treatment accelerated this process to just four weeks. Methylparaben followed a similar trend, achieving complete degradation by the seventh week. This study highlights the potential of microbial CW systems fortified with targeted microbial consortia as a scalable solution for pollutant removal. Future work should refine microbial combinations and analytical methods to expand the range of treatable pollutants.