Microplastic and microfiber fluxes in the Seine River: Flood events versus dry periods

Studies on the influence of hydrodynamic conditions anthropogenic microfiber (MF) and microplastic (MP) distributions in freshwater environments are sparse. In this study, we evaluated urbanisation gradient spatial variability MFs MPs. Temporal was also assessed by comparing concentrations fluxes MPs under low flow with those during January–February 2018 flood event. For each period, Seine river water collected upstream downstream Greater Paris filtered through an 80 ?m net at three different sampling sites. were counted using a stereomicroscope, while analysed micro-Fourier transform infrared spectroscopy coupled siMPle analysis software. The highest reported furthest sites both periods. However, high flowrates did not significantly impact MF MP concentrations, sizes, or polymer distributions. median 2.6 15.5 items/L their interquartile ranges 1.6 4.9 (n = 10), respectively, illustrating relatively stable spite variations flowrate. contrast to concentration, size, distribution characteristics, mass strongly affected flow. show increases number particles from downstream. site presents fluxes, which range between 924 1675 tonnes/year. These results may indicate significant inputs Megacity wastewater treatment plant effluents untreated stormwater. event, represented 14.5% year (in terms time), contributed 40% yearly fluxes. Thus, events contribute