Entrainment and vertical mixing of aquatic microplastics in turbulent flow: The coupled role of particle size and density

Assessing the Behavior of Microplastics in Fluvial Systems: Infiltration and Retention Dynamics in Streambed Sediments

“…For larger particles between 1–3 mm, the location of MPs in the water column is similar to mineral sediments (Born et al., 2023), indicating that higher density MPs are more likely to be transported near the streambed. Conversely, turbulent mixing, such as caused by the weir overflow in our experiment, can also transport low density MPs to the streambed interface (Shamskhany & Karimpour, 2022). Within streambed sediments, low‐density MPs, such as polyethylene and polypropylene, exhibit higher mobility, whereas high‐density MPs, auch as polyamide and polyethylene terephthalate, are retained (He et al., 2021).…”

Rising seas and roadway debris: Microplastic and low-density tire wear particles in street-associated tidal floodwater

“…The higher density of brackish water (≤1.02 g/mL) associated with the tidal floodwater in this study may have resulted in more MP floating off of the street surface relative to the lower density of rainfall (1.00 g/mL) associated stormwater. Additionally, recent studies have investigated how the transport and settling of MPs in water may be influenced by turbulent dispersion (Cardoso-Mohedano et al, 2023;Shamskhany and Karimpour, 2022). Shamskhany and Karimpour (2022) observed that vertical settling of MPs < 200 µm is dominated by turbulent dispersion more so than gravitational settling.…”

“…Additionally, recent studies have investigated how the transport and settling of MPs in water may be influenced by turbulent dispersion (Cardoso-Mohedano et al, 2023;Shamskhany and Karimpour, 2022). Shamskhany and Karimpour (2022) observed that vertical settling of MPs < 200 µm is dominated by turbulent dispersion more so than gravitational settling. Mild turbulence was observed in the present study as the result of either tidal waters flooding onto the street or vehicles driving through the floodwater (Fig.…”

Physical processes matters! Recommendations for sampling microplastics in estuarine waters based on hydrodynamics

“…Vertical transport became particularly important in shallow waters. For instance, vertical mixing is a key process in transferring suspended particulate matter from the bottom to the surface and for keeping small particles in suspension (Shamskhany and Karimpour, 2022). Surface sampling is certainly not representative of MP contamination, underestimating MP fluxes by avoiding suspended MPs inside the water column (Defontaine et al, 2020;Gasperi and Cachot, 2021).…”