Access to safe drinking water remains a critical global challenge, exacerbated by contamination of sources and the operational limitations of conventional treatment. In response, this systematic review evaluates the performance and synergistic integration of nanofiltration, ozonation, and ultraviolet disinfection. Following PRISMA and PICO methodologies, 42 peer-reviewed studies (2020–2025) were analyzed with an explicit focus on drinking water quality and safety. Findings indicate that nanofiltration acts as a robust physical barrier against salts and emerging contaminants. Concurrently, ozonation serves as a chemical oxidant to degrade complex organic compounds, while ultraviolet disinfection provides efficient biocidal action without generating toxic by-products. Crucially, integrating these technologies into hybrid multi-barrier systems helps overcome individual operational limitations, such as mitigating membrane fouling and suppressing microbial photoreactivation. Practically, transitioning these hybrid systems to full-scale operations requires managing toxic concentrates and mitigating secondary by-products. Furthermore, deployments must prioritise modular scaling and integration with renewable energy sources. Addressing these factors is essential to provide sustainable, multi-barrier purification strategies for vulnerable regions with limited infrastructure.
Delgado-Sernaque et al. (Thu,) studied this question.