Microalgae-based remediation of pharmaceutical contaminants: Emerging strategies and technological synergies

In recent years, the pharmaceutical sector has undergone significant expansion, leading to increased use and unregulated discharge of pharmaceutical compounds (PhCs) into aquatic environments. This has resulted in adverse impacts such as antibiotic resistance, endocrine disruption, and hormonal imbalances among others. Effective treatment of PhCs-laden wastewater is crucial before environmental discharge. Phycoremediation, using algae, offers a promising approach for treating these emerging contaminants. This review systematically analyzes current phycoremediation trends, highlighting key mechanisms such as biotransformation, biodegradation, and photodegradation by various algal species. Integrating phycoremediation with technologies like high-rate algal ponds, photobioreactors, constructed wetlands, up-flow anaerobic sludge blanket reactors, and advanced oxidation processes have demonstrated enhanced PhC removal, with efficiencies ranging from 40–100% depending on the PhC and algal species. Algal–bacterial consortia and integration with advanced oxidation processes show particular promise for improved removal. Furthermore, this review explores the potential of artificial intelligence and machine learning for optimizing phycoremediation strategies and discusses future research directions for maximizing PhC removal and resource recovery from pharmaceutical wastewater.