Department of Ocean Sciences, Tokyo University of Marine Science and Technology, Konan 4-5-7, Minato-Ku, Tokyo 108-8477, Japan.
Aquatic Resources Research Institute, Chulalongkorn University, 254 Institute Building 3, Pyathai Road, Patumwan, Bangkok, Thailand.
Mar Pollut Bull. 2024 Nov;208:116957. doi: 10.1016/j.marpolbul.2024.116957. Epub 2024 Sep 10.
In this study, microplastic concentrations in the southeastern coastal regions of Japan were measured along the northward ocean current at seven stations from Okinawa to Tokai region. Concentrations ranged from 0.014 to 0.094 pieces/m, except for a station near the Bungo Channel mouth, which had 0.723 pieces/m. Polystyrene (PS) foam was most prevalent near the east side of Kyushu, suggesting origination from nearby coastal areas. Fragmentation levels were higher in the Tokai region. In addition, carbonyl index (CI) of polyethylene (PE) microplastics increased northward, indicating northward movement from southern regions. Standard PE microplastics showed chemical treatment does not significantly alter CI values. Further spectral analysis suggested potential oxidation of polypropylene (PP) and PS foam by chemical treatment. This study provides a comprehensive understanding of the abundance, distribution, and characteristics of microplastics in the southeastern coastal regions of Japan in the northwest Pacific, enhancing the understanding of environmental fate of microplastics.
在这项研究中，测量了日本东南部沿海地区从冲绳到东海地区的七个站点沿北向海流的微塑料浓度。浓度范围从 0.014 到 0.094 片/米，除了丰后水道口附近的一个站点，其浓度为 0.723 片/米。在九州东侧附近最常见的是聚苯乙烯（PS）泡沫，表明其起源于附近的沿海地区。东海地区的碎片水平更高。此外，聚乙烯（PE）微塑料的羰基指数（CI）向北增加，表明它们从南部地区向北移动。标准 PE 微塑料表明化学处理不会显著改变 CI 值。进一步的光谱分析表明，化学处理可能会导致聚丙烯（PP）和 PS 泡沫发生氧化。本研究全面了解了西北太平洋日本东南部沿海地区微塑料的丰度、分布和特征，增强了对微塑料环境归宿的理解。
