Non-thermal plasma for the removal of pharmaceuticals from water: a systematic evaluation of configurations, efficiency, and implementation barriers

Pharmaceutical pollution in aquatic environments represents a persistent global challenge, as conventional wastewater treatment plants fail to remove recalcitrant compounds such as antibiotics. Non-thermal plasma-based technologies have gained significant attention as efficient and versatile approaches for degrading emerging contaminants through chemical oxidation and mineralisation, typically without the addition of chemical reagents. However, a comprehensive synthesis of their effectiveness and limitations is still needed to evaluate their environmental relevance. This systematic review critically assesses 62 peer-reviewed research studies published between 2009 and 2025, covering 21 pharmaceutical classes and multiple plasma configurations. The review additionally examines temporal and geographic research trends, mechanistic pathways, transformation product toxicity, and antimicrobial resistance implications. Dielectric barrier discharge (DBD) plasma dominates the literature (51.6%), followed by corona discharge (19.4%) and atmospheric plasma jets (11.3%). High parent compound removal or degradation (>90%) is consistently reported across pharmaceutical classes, with antibiotics (33%) being the most frequently studied. Despite this progress, most investigations remain at laboratory scale, and considerable variability and limited standardisation persist in performance metrics, mineralisation efficiency, toxicity assessment, and energy reporting. Energy efficiency remains a principal constraint, hindering meaningful comparison with established treatment technologies and comprehensive techno-economic assessment. Future research should prioritise energy-efficient reactor design, standardised methodologies, system scale-up, testing in real wastewater matrices, and integration within sustainable energy–water systems to support the transition from laboratory research to full-scale implementation. Overall, this review highlights the potential of non-thermal plasma technologies for pharmaceutical removal while identifying key challenges that must be addressed to facilitate their practical deployment.