Celik Murat, Zijiang Yang, Xu Haodong, Nakano Haruka, Isobe Atsuhiko, Arakawa Hisayuki
Tokyo University of Marine Science and Technology, 5-7, Konan-4, Minato, Tokyo 108-8477, Japan.
Tokyo University of Marine Science and Technology, 5-7, Konan-4, Minato, Tokyo 108-8477, Japan.
Mar Pollut Bull. 2025 Feb;211:117376. doi: 10.1016/j.marpolbul.2024.117376. Epub 2024 Dec 4.
We investigated the carbonyl index (CI) of small microplastics (SMPs; 50-350 μm) and large microplastics (LMPs; >350 μm) in the surface waters of the Tokai region and Tokyo Bay in Japan. The degradation was evaluated by determining the CI from the infrared spectrum of microplastics (MPs) adopting the specified area under the band technique. Average CIs of SMPs and LMPs in polyethylene were 2.47 and 0.67 off Tokai and 2.71 and 0.76 in Tokyo Bay, respectively. No significant differences in the CI were found between polyethylene and polypropylene. However, significant differences in CIs were found between SMPs and LMPs. The relationship between the major length of MPs and CI was significantly negative for both polyethylene and polypropylene (p < 0.05). The results indicate that as MPs degrade, they become finer and exhibit a higher CI at the sea surface.
我们调查了日本东海地区和东京湾表层水中小型微塑料（SMPs；50 - 350μm）和大型微塑料（LMPs；>350μm）的羰基指数（CI）。采用谱带技术指定面积下的微塑料（MPs）红外光谱测定CI来评估降解情况。东海地区聚乙烯中SMPs和LMPs的平均CI分别为2.47和0.67，东京湾分别为2.71和0.76。聚乙烯和聚丙烯之间的CI没有显著差异。然而，SMPs和LMPs之间的CI存在显著差异。聚乙烯和聚丙烯的MPs主要长度与CI之间的关系均呈显著负相关（p < 0.05）。结果表明，随着MPs降解，它们变得更细小，且在海面呈现出更高的CI。
