When every particle matters: A QuEChERS approach to extract microplastics from environmental samples

Enders, Kristina; Lenz, Robin; Sul, Juliana A. Ivar do; Tagg, Alexander S.; Labrenz, Matthias

doi:10.1016/j.mex.2020.100784

Cited by 64 publications

(82 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Test samples (a)-(c) were baked for 5 h at 500 • C to eliminate any MP contamination present in the sample which would potentially hinder a quick determination of the recovery rates. The soil samples (d) were not baked but freeze dried (according to Enders et al, 2020) as both the organic fraction was intended to be preserved and the determination and thus conservation of environmental MP was targeted in addition to the recovery rates of the spiked MP standards.…”

Section: Preparationmentioning

confidence: 99%

“…For example, run repetitions were set to five (instead of three) in order to increase the mass reduction. Subsequently, a small-scale density separation was performed according to Enders et al (2020) to allow unhindered identification of the spiked test-MP. A schematic overview of the separation steps can also be found in Felsing et al (2018, Figure 3).…”

Section: Preparationmentioning

confidence: 99%

“…This ineffectiveness of the KWS was postulated to be due to the high levels of silt and clay particulates present in soils (especially agricultural soils). Therefore, drysieving to remove the <100 µm quotient was applied (according to Enders et al, 2020). After a further six runs of the sieved sample, the mass was reduced overall by ∼15% (total eight runs taking ∼7 h per 500g w/w sample, not including reductions of the sieved-out fraction).…”

Section: Soilsmentioning

confidence: 99%

“…The Munich Plastic Sediment Separator has been designed to density separate larger volumes, though, it appears to be a rather laborintensive method (Imhof et al, 2012). Electrostatic separation is not as exhaustive as density separation in eliminating the entire mineral fraction (99.98 ± 0.03%, Enders et al, 2020), although approximately 98% mass could be reduced in previous tests in just 5 h (Felsing et al, 2018). However, due to deviating objectives a direct comparison to other established methods is difficult (though respective reviews exists, see Stock et al, 2019).…”

Section: Introductionmentioning

confidence: 99%

“…• a reasonable mass reduction of the initial sample mass that allows for a subsequent quick and easy density separation in a separation funnel [as presented in Enders et al (2020)] • reasonable and reproducible (i.e., consistent) recovery rates of MP • low influence of matrix-related variables (i.e., grain size, mineral composition) on recovery rates and mass reduction…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Evaluation of Electrostatic Separation of Microplastics From Mineral-Rich Environmental Samples

Enders

Tagg

Labrenz

2020

Front. Environ. Sci.

Self Cite

View full text Add to dashboard Cite

Reliable, easy, cost-effective and reproducible ways of extracting microplastics (MP) from environmental samples remain important requirements for MP research. In this context, electrostatic separation is a new proposition, especially for extracting MP from mineral-rich samples and large sample volumes. However, there is little research evaluating the reliability of the technique. This study has evaluated the effectiveness of the Korona-Walzen-Scheider (KWS) system; a small-scale version of larger machines designed to sort recycling materials. Recovery rates of a variety of sizes of MP, spiked in beach sediments, were found to be highly dependent on the MP size. MP ≥ 2 mm achieved 99-100% recovery (with the exception of fibers: ∼80%), MP of 63-450 µm achieved ∼60-95% recovery and MP of 20 µm achieved ∼45% recovery. For particle-based analysis, additional density separation is still inevitable for the analysis of small MP after KWS separation and further reduces the overall recovery rates. Mass reduction rates of beach and commercial reference sand greatly differed, 93 and 17%, respectively. Mineral analysis using SEM-EDX suggested that lower reduction rates found in commercial sand was due to high presence of small (<50 µm) calcite particles. Tests based on environmental soil samples revealed comparatively low mass reduction rates (∼1%), suggesting that KWS treatment was inefficient for soils due to high levels of fine particulates. Sieving to remove fine particles improved mass reduction, though only to ∼15%. To specifically test for influence of fine particulates, recovery rates were determined for sand samples spiked with a defined amount of silicate dust, resulting in a reduction of certain MP recovery rates, especially medium-sized (450 µm) MP. Conclusively, several key influential parameters were identified, such as mineral composition and grain size, that can negatively effect sediment mass reduction as well as MP recovery rates. Given the variability in recovery rates, the use of internal standards is recommended when using the KWS, particularly for smaller MP (<500 µm). For largevolume (beach) sand samples, where interest is mainly in MP > 450 µm, electrostatic separation is a reliable and fast approach for MP extraction from the environment.

show abstract

Section: Preparationmentioning

confidence: 99%

Section: Preparationmentioning

confidence: 99%

Section: Soilsmentioning

confidence: 99%