Quantification of Microplastics contribution by the city of Rome to Tiber River water column and their interception by Alborella (Alburnus arborella)

Rivers act as conveyor belts to the sea by carrying and concentrating microplastics (MP) from urban, and extra-urbane areas. Nevertheless, there is still scarce information regarding quantity, quality, and temporal variation of the urban contribution to riverine MP transport. Furthermore, the MP interception by riverine biota, especially by different fish species with different feeding strategies, is largely unknown. In this framework, the aim of this study was to investigate the MP concentration both in the water column of the Tiber River and into the tissues of the inhabiting A. Arborella. In order to state the urban contribution from the City of Rome (Central Italy), we compared two different areas, first one located upstream the urban stretch and second one located downstream. The correlation in terms of n. of MP fibres, spheres, and fragments was assessed both in water-column and riverine fish tissues (brain, liver, kidney, gonads, filet, and gastrointestinal tract).