Settling and Rising Velocities of Environmentally Weathered Micro- and Macroplastic Particles.

Settling and Rising Velocities of Environmentally Weathered Micro- and Macroplastic Particles. Environ Res. 2020 Sep 18;:110192 Authors: Waldschläger K, Born M, Cowger W, Gray A, Schüttrumpf H Abstract Microplastic is exposed to numerous weathering processes in the environment, which change particle properties and thus influence transport behaviors, including settling and rising velocities in aquatic environments. However, the extent to which particles in the environment differ from virgin particles in their transport behaviors has not yet been investigated. The settling and rising velocities of weathered fluvial microplastic and macroplastic particles collected from environmental samples are determined in this study and the transferability of theoretical approaches to predicting their transport behaviors is examined. The settling velocities of the environmental particles were between 0.16 and 3.52 cm/s and the rising velocities between 0.18 and 19.85 cm/s. Formulas were applied that were developed using experiments with virgin microplastic, but do not account for the effects of environmental impacts such as degradation, fragmentation and biofouling on the velocities. Accordingly, the transferability of the formulas to environmental particles must be verified. The formulas proved to be suitable for describing the settling and rising velocities of environmental microplastic particles in the shapes of pellets, fragments and foams, an...
Source: Environmental Research - Category: Environmental Health Authors: Tags: Environ Res Source Type: research