Plastic pollution in freshwater environments is a pressing global concern due to its ability to accumulate in the environment. The long-term impacts of this pollution on freshwater ecosystems are still to understand. In PATTERN project, we aim to understand how plastics can influence nutrient composition and the natural exchanges in biological information, with a focus on the biofilms colonizing plastic’s surface. We aim to rate the environmental relevance of these processes and to assess the threshold at which plastic pollution disrupts freshwater ecosystem functioning.