Advancing water treatment and reuse technologies to address the nexus of climate change, water scarcity, and pharmaceutical contamination

Abstract

Climate change is intensifying water scarcity, degrading water quality, and increasing the persistence of emerging contaminants (ECs) such as pharmaceuticals, antibiotics, and antibiotic resistance genes (ARGs). These converging stressors threaten ecosystem stability and water security, particularly in semi-arid regions such as the Mediterranean. This review critically examines the intersection of climate change, water scarcity, and pharmaceutical pollution, and evaluates advanced treatment and reuse technologies to support climate-resilient water management. High-performance systems such as membrane bioreactors (MBRs), nanofiltration (NF), reverse osmosis (RO), and anaerobic MBRs (AnMBRs) achieve 70–99 % removal of pharmaceuticals and ARGs, with EC–RO hybrids reaching 97–99 % COD, TSS, and BOD removal. However, these technologies remain inherently limited by fouling, brine disposal, and energy costs. Peroxymonosulfate (PMS)-based advanced oxidation processes (AOPs) and hybrid systems deliver 83–99.9 % removal of recalcitrant pharmaceuticals and up to 94.5 % ARG reduction, though scaling and by-product management remain barriers. Nature-based solutions, including hybrid constructed wetlands (15–>99 % removal) and biochar-enhanced systems (40–210 mg/g adsorption; up to 95 % removal), provide sustainable but land-intensive alternatives. Decentralized approaches such as microbial fuel cells (MFCs) (85–99 % removal), biosorbents, and green nanomaterials (64–95 % removal) demonstrate strong potential for low-energy reuse in resource-limited settings. Aligning these technologies within circular water strategies supported by pilot programs, adaptation finance, life-cycle assessments, and inclusive governance is essential to ensure water quality, availability, and resilience under climate pressures.