Evaluating the effectiveness of the MicroPlastic Sediment Separator (MPSS)

Effective laboratory methods are a requirement to obtain accurate data on the contamination of the environment with microplastics. However, current methods often lack specification and validation of performance. The aim of this work was to provide the first evaluation of the effectiveness of the commercially available MicroPlastic Sediment Separator (MPSS) operated with sodium chloride. We performed density separation experiments with pristine plastic particles spiked into both commercial sand (experiment I) and natural river sediments (experiment II) and with environmental microplastics contained in natural river sediments (experiment III). The natural sediments were taken from the Lahn River in Germany, a medium-scale central European tributary. The pristine test particles were ground polypropylene fragments, sieved in three different size classes: larger than 1 mm, 0.5–1 mm, and 0.3–0.5 mm. In experiment I, the mean recovery rate was 97