0
Article ? AI-assigned paper type based on the abstract. Classification may not be perfect — flag errors using the feedback button. Sign in to save

Field Survey of Marine Microplastics on the Western Coast of Okinawa Main Island — Evaluation of Degradation by Infrared Spectroscopy and Thermal Analysis

Original title: 沖縄本島西海岸における海洋マイクロプラスチックの実態調査 -赤外分光と熱分析による劣化の評価-

Current World Environment 2025
Manami Tohyama, Shunki Takara, Keiko Nakasone

Summary

This Japanese study surveyed microplastics on beaches along the west and east coasts of Okinawa Island, finding polyethylene as the most prevalent polymer type (51%) followed by polypropylene (30.2%) based on FT-IR spectroscopy. Thermogravimetry measurements showed that UV degradation had lowered the initial thermal decomposition temperatures of collected microplastics, indicating environmental weathering.

Polymers

Drifting ashore of microplastics on four west coast beaches and two east coast beaches in Okinawa Island, Japan is reported. Microplastics (MPs) is a term used to describe very small plastic particles that are under 5 mm in diameter. MPs were separated from the sands using gravity separation. Fourier-transform infrared spectroscopy (FT-IR) indicated that polyethylene was the most commonly used polymer type, accounting for 51.0% of the total MPs, followed by polypropylene at 30.2%. FT-IR spectra of many MPs indicated new absorption band of carbonyl group caused by degradation. According to thermogravimetry (TG) measurements, the initial phase of thermal decomposition for MPs reaction was observed decreasing into lower temperatures.

Share this paper