Extraction of microplastic from marine sediments: A comparison between pressurized solvent extraction and density separation

Due to the ecotoxicological effects, microplastics are considered a threat for the marine environment. Recent reports indicate their presence not only in subsurface water and in coastal beach sediments, but also in the deepsea. Notwithstanding, there is still not a scientific consensus about the analytical procedure to be applied for their determination. In this work we compared the performance of two extraction methods: pressurized solvent extraction (PSE) and density separation. Sea sand and seafloor sediments were spiked with known amounts of polystyrene (PS), polyethylene (PE) and polypropylene (PP) microplastics and submitted to both the extraction procedures. Results showed that the PSE ensured higher recoveries for the smaller size particle fractions (89,2 +/- 1.1% in the 50-150 mu m range) whereas the density separation enabled precise recoveries for the larger size particles (SD = 1,5%). No significant differences in terms of blanks control were highlighted.

Automated summary

The study compared two extraction methods for microplastics and found that pressurized solvent extraction (PSE) is suitable for smaller particle sizes, while density separation is effective for larger particle sizes, with no significant differences in terms of blanks control between the two methods.