Oceanographic modelling is widely used to study the pathways and fate of marine pollutants such as oil spills, plastic litter, radionuclides and other contaminants. In this session, advanced models, operational applications and techniques related to polluting tracers on local, regional and global scales will be discussed, as well as the coupling with met-oceanographic transport fields from operational oceanography products such as Copernicus Marine Monitoring Environment Service. Parcel trajectory numerical schemes, ensemble and multi-model methods, uncertainties estimation, risk algorithms and decision support systems are solicited topics. Impacts of pollutants on the marine ecosystem and resilience to pollution events are also important subjects for discussion. Integration of modelling and observing systems both for data assimilation and validation are also very welcome.