A review of in-situ technologies for enhancement of the removal of pharmaceuticals and personal care products (PPCPs) and mitigation of membrane fouling in membrane bioreactors

• Recent in-situ fouling reduction technologies in membrane bioreactors are reviewed. • Biofilm configuration enhances biomass retention and pharmaceutical biodegradation. • Adsorption can adsorb extracellular polymeric substances (EPS) - related foulants. • Electrical assisted membrane bioreactor enhances pharmaceutical oxidation. • Future membrane bioreactor systems should consider energy-efficient technologies. The widespread presence of pharmaceuticals and personal care products (PPCPs) in wastewater, along with the persistent issue of membrane fouling, has intensified the demand for enhanced membrane bioreactor (MBR) performance. This review critically evaluates in-situ technologies designed to improve PPCP removal while reducing membrane fouling within MBR systems. Strategies include MBR configuration modifications, optimization of operational parameters, microbial manipulation approaches, and the dosing of exogenous physicochemical additives (e.g., activated carbon, coagulants, iron-based compounds). Furthermore, advanced techniques such as electrically assisted MBR, advanced oxidation process (AOP) assisted MBRs, and the development of novel membrane materials and surface coatings are discussed for their dual functionalities in pollutant removal and fouling resistance. Each approach presents specific advantages and limitations in terms of removal efficiency, operational complexity, cost, and environmental impact. This review emphasizes the importance of integrating multiple strategies in a synergistic manner, supported by intelligent monitoring, automation, and sustainability principles. Future advancements should focus on hybrid systems that combine biological, chemical, and physical enhancements with cost-effective and energy-efficient operation, paving the way for next-generation MBR technologies capable of delivering high-performance, low-impact wastewater treatment.