Affiliation:
1. Institute of Hydraulic Engineering and Water Resources Management E222/2 TU Wien Vienna Austria
2. Interuniversity Cooperation Centre (ICC) Water and Health Vienna Austria
3. Institute for Hygiene and Applied Immunology, Water Microbiology Medical University of Vienna Vienna Austria
4. Division Water Quality & Health Karl Landsteiner University of Health Sciences Krems an der Donau Austria
Abstract
AbstractMicroplastics in urban runoff undergo rapid fragmentation and accumulate in the soil, potentially endangering shallow groundwater. To improve the understanding of microplastic transport in groundwater, column experiments were performed to compare the transport behavior of fragmented microplastics (FMPs ∼1‐µm diameter) and spherical microplastics (SMPs ∼1‐, 10‐, and 20‐µm diameter) in natural gravel (medium and fine) and quartz sand (coarse and medium). Polystyrene microspheres were physically abraded with glass beads to mimic the rapid fragmentation process. The experiments were conducted at a constant flow rate of 1.50 m day−1 by injecting two pore volumes of SMPs and FMPs. Key findings indicate that SMPs showed higher breakthrough, compared to FMPs in natural gravel, possibly due to size exclusion of the larger SMPs. Interestingly, FMPs exhibited higher breakthrough in quartz sand, likely due to tumbling and their tendency to align with flow paths, while both sizes (larger and smaller relative to FMPs) of SMPs exhibited higher removal in quartz sand. Therefore, an effect due to shape and size was observed.