Bibliometric analysis of nanoplastics in drinking water and policy implications

Nanoplastics in aquatic environments represent an emerging class of contaminants due to their small size, high mobility, and ability to interact with pollutants and biological systems. Nanoplastics can interact with their surroundings through the adsorption and transport of organic pollutants and metal ions, the release of polymer additives, interactions with natural organic matter and biomolecules, aggregation with other particles, and interactions with biological membranes and cellular components. This study presents a bibliometric analysis of 239 research articles on nanoplastics in drinking water retrieved from the Web of Science, covering the period from 2018 to April 2026. The results reveal rapid growth in this field, accompanied by a clear thematic asymmetry: current research is dominated by environmental pollution and toxicological studies, while analytical methods, water treatment, and distribution systems remain underexplored. Research output is concentrated in high-impact Q1 and Q2 journals, with China, the USA, and Canada being the primary contributors. The findings indicate a temporal shift in focus from microplastics to nanoplastics, driven by advances in the understanding of fragmentation processes and environmental impacts. Future research should prioritise drinking water as a direct exposure pathway, emphasising the development of effective removal technologies, minimising the release of nanoplastics in distribution systems, and establishing reliable analytical methods for routine monitoring. In parallel, the absence of standardised regulations highlights the urgent need for legislative frameworks to define monitoring protocols, limit values, and risk assessment strategies for the presence of nanoplastics in drinking water. These findings have direct implications for regulatory development and water policy.