The main objective of PLASTACTS is to provide a thorough understanding of the sources, fate of micro- and nanoplastics (N/MPs), and to develop an analytical protocol to identify, characterize and assess the impact of N/MPs. For this objective PLASTACTS will consider the development of environmentally relevant testing materials that better mirror the broad heterogeneity of naturally occurring N/MPs, as well the detection and occurrence in a real environment of macro, meso and microplastics, in order to support the holistic understanding of the plastic pollution in the environment. Moreover, the impact on biota of N/MPs with different composition, shape, size, and degradation state will be evaluated using well-established methods for the dynamics of uptake, accumulation and egestion in mussels.