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Microplastic ingestion by sea turtles around Tokyo Bay: Level of water pollution influences ingestion amounts

Marine Pollution Bulletin 2024 6 citations ? Citation count from OpenAlex, updated daily. May differ slightly from the publisher's own count. Score: 55 ? 0–100 AI score estimating relevance to the microplastics field. Papers below 30 are filtered from public browse.
Riko Kimura, Emi Inoguchi, Chiyo Kitayama, Masaki Michishita, Ryosuke Fujinuma, Ryosuke Fujinuma

Summary

Researchers examined the stomach contents of sea turtles found inside and outside Tokyo Bay and found that turtles in the more polluted bay area ingested significantly more microplastics. The microplastics were linked to pollution flowing in from major rivers that empty into the bay. The study demonstrates a direct connection between regional water pollution levels and microplastic ingestion in marine wildlife.

Body Systems
Study Type Environmental

We investigated the contents inside the esophagus and stomach of turtles inside and outside of the Tokyo Bay area, which face high and low risks of microplastic (MP) exposure, respectively. 65 synthetic particles were recovered from 8 out of 22 turtles, using ATR-FTIR followed by density separation with calcium chloride solution. Statistical analysis indicated that turtles in high-risk areas ingested significantly more MPs than those in low-risk areas. As the inflow of MPs from major rivers influences pollution levels in the ocean, the results of this study highlight the importance of major rivers for MP ingestion by turtles. Additionally, we discussed the current methodology's shortcomings and addressed scope for subsequent research, along with suggestions on future conservation.

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