State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P. O. Box 2871, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
Key Laboratory for Ecological Environment in Coastal Areas, Ministry of Ecology and Environment, National Marine Environmental Monitoring Center, Dalian 116023, China.
Sci Total Environ. 2023 Jul 10;881:163222. doi: 10.1016/j.scitotenv.2023.163222. Epub 2023 Apr 3.
Micro- and nano-plastic (MNP) pollution has attracted public concerns. Currently, most environmental researches focus on large microplastics (MPs), while small MNPs that have great impacts on marine ecosystems are rarely reported. Understanding the pollution levels and distribution patterns of small MNPs could help assess their potential impacts on the ecosystem. Polystyrene (PS) MNPs were often used as models to assess their toxicity, hence, we collected 21 sites in a Chinese sea area (the Bohai Sea) to analyze their pollution level and horizontal distribution in surface water samples, and vertical distributions in five sites with the water depth >25 m. Samples were filtered by glass membranes (1 μm) to trap MPs, which were frozen, ground, dried, and detected by pyrolysis-gas chromatography-mass spectrometry (pyGC-MS); while the nanoplastics (NPs) in the filtrate were captured with alkylated ferroferric oxide (FeO) to form aggregates, which were separated by glass membrane (300 nm) filtration for pyGC-MS determination. Small PS MPs (1-100 μm) and NPs (<1 μm) were detected in 18 samples with the mass concentrations ranging from <0.015 to 0.41 μg/L, indicating that PS MNPs are widely present in Bohai Sea. Our study contributes to understanding the pollution levels and distribution patterns of MNPs (<100 μm) in the marine system and provides valuable data for their further risk assessment.
微纳米塑料（MNP）污染引起了公众的关注。目前，大多数环境研究都集中在大尺寸微塑料（MPs）上，而对海洋生态系统有重大影响的小尺寸 MNPs 则很少被报道。了解小尺寸 MNPs 的污染水平和分布模式有助于评估它们对生态系统的潜在影响。聚苯乙烯（PS）MNPs 常被用作评估其毒性的模型，因此，我们采集了中国海域（渤海）的 21 个站位的水样，分析了其表层水中的污染水平和水平分布，并在水深>25 m 的 5 个站位分析了其垂直分布。水样通过玻璃膜（1 μm）过滤以捕获 MPs，然后将 MPs 冷冻、研磨、干燥，并通过热裂解气相色谱-质谱联用仪（pyGC-MS）进行检测；而滤液中的纳米塑料（NPs）则用烷基化的四氧化三铁（FeO）捕获形成聚集体，然后通过玻璃膜（300 nm）过滤分离，用于 pyGC-MS 测定。在 18 个样品中检测到小尺寸 PS MPs（1-100 μm）和 NPs（<1 μm），其质量浓度范围从<0.015 到 0.41 μg/L，表明 PS MNPs 广泛存在于渤海。本研究有助于了解海洋系统中 MNPs（<100 μm）的污染水平和分布模式，并为进一步的风险评估提供了有价值的数据。
