Center for Environmental Metrology, National Institute of Metrology PR China, PR China.
State Environmental Protection Key Laboratory of Quality Control in Environmental Monitoring, China National Environmental Monitoring Center, PR China.
Chemosphere. 2022 Feb;289:133187. doi: 10.1016/j.chemosphere.2021.133187. Epub 2021 Dec 7.
Mussels are often used as biological indicators for monitoring marine microplastic pollution. The crucial procedure during monitoring is the separation of microplastics from mussel samples. We investigated the separation efficiencies of six combinations of two digestion solutions (10% KOH and 30% HO) and three extraction solutions (NaCl, oil in HO, and oil in NaCl) for mussels with low- and high-density microplastics. After KOH digestion, no polyethylene terephthalate (PET) could be extracted using the three extraction solutions, which might be due to the degradation of PET. After HO digestion, the total extraction recovery rates of polypropylene, polyvinyl chloride, and PET for oil in HO and oil in NaCl solution ranged from 95.6% ± 5.09%-100%, which were higher than those of the saturated NaCl solution (51.1% ± 17.1%-67.8% ± 13.9%). The first extraction recovery rates of oil in NaCl solution for PP, PET, and PVC were higher than those of oil in HO. In this study, extraction by oil in NaCl solution after 30% HO digestion was suggested to separate microplastics from mussels. This method is conducive to promoting the standardization of microplastic monitoring in mussels and might be suitable for large-scale monitoring of marine microplastic pollution.
贻贝常被用作监测海洋微塑料污染的生物指标。在监测过程中，关键步骤是将微塑料从贻贝样本中分离出来。我们研究了两种消解液（10% KOH 和 30% HO）和三种提取液（NaCl、HO 中的油和 NaCl 中的油）六种组合对低浓度和高浓度微塑料贻贝的分离效率。KOH 消解后，三种提取液均无法提取聚对苯二甲酸乙二醇酯（PET），这可能是由于 PET 的降解。HO 消解后，HO 中的油和 NaCl 中的油对聚丙烯、聚氯乙烯和 PET 的总提取回收率在 95.6%±5.09%-100%之间，高于饱和 NaCl 溶液（51.1%±17.1%-67.8%±13.9%）。NaCl 溶液中油对 PP、PET 和 PVC 的首次提取回收率高于 HO 中的油。在本研究中，建议在 30%HO 消解后使用 NaCl 溶液中的油提取法来分离贻贝中的微塑料。这种方法有利于促进贻贝中微塑料监测的标准化，可能适用于海洋微塑料污染的大规模监测。
