Urban stormwater runoff (2018–2024). Sci Data 13, 784 (2026). https://doi.org/10.1038/s41597-026-07137-y. “Microplastic (<5 mm) pollution is a growing environmental concern, with urban stormwater systems serving as critical transport pathways. While microplastics predominantly originate and circulate within urban environments, transported via stormwater runoff to receiving water bodies, existing datasets focus almost exclusively on marine and coastal waters. This mismatch between contamination sources and data infrastructure has left urban stormwater systems without dedicated data resources to support research and management. In this research, we present the Dataset of Urban RUnoff Microplastics (DURUM), a global dataset dedicated to microplastics in urban stormwater runoff. The objective of DURUM is to compile, standardize, and serve urban runoff microplastic data in a consistent format to enable data-driven approaches for developing predictive transport models. DURUM systematically compiles 180 sampling efforts from peer-reviewed studies published between 2018 and 2024, encompassing surface runoff from streets, residential catchments, commercial districts, industrial areas, and drainage infrastructure across 15 countries. This paper describes DURUM’s structure, compilation methodology, standardization protocols, and future research directions.”