Assistant Professor The University of Tennessee at Chattanooga, United States
Abstract Submission: Microplastics (MPs), defined as plastic particles smaller than 5 mm, have garnered increasing attention in recent years due to their widespread presence in the environment. They pose a potential threat to ecosystems, various species, and human health. Soil-amended bioretention cells offer a sustainable approach to mitigating environmental risks by trapping pollutants from the environment. This study evaluated the efficacy of bioretention cells in removing small-sized MPs from stormwater runoff and investigated the vertical retention profile of MPs within these systems. Numerous sediment samples were collected from field-installed bioretention cells at various depths and processed in the laboratory for microscope analysis. MPs were identified using advanced fluorescence techniques and FTIR analysis. Our findings revealed that bioretention systems are effective in trapping small-sized MPs (25 μm) from stormwater runoff. The concentration of MPs ranged from 25 to 89 items per 50 g of dried sediment, with most MPs found in fragment form. While the concentration of MPs was relatively higher at greater depths, no clear vertical distribution pattern was established. These research findings can provide valuable insights to researchers, regulators, and engineers for addressing microplastics pollution and managing stormwater infrastructure in the future.