Microplastics are tiny plastic particles that can be found in the environment. They can be ingested by animals, including fish, and can have negative effects on their health. A new technique that can show the link between prey and microplastics has been developed by researchers at the University of Plymouth.

The technique uses a combination of fluorescence microscopy and Raman spectroscopy. Fluorescence microscopy can be used to detect microplastics in water samples, while Raman spectroscopy can be used to identify the type of plastic. This allows researchers to track the movement of microplastics through the food chain and identify the sources of microplastic pollution.

The researchers tested the technique on a variety of fish species, including mackerel, herring, and pollock. They found that microplastics were present in the stomachs of all of the fish species tested, and that the concentration of microplastics increased with the size of the fish. This suggests that larger fish are more likely to ingest microplastics, and that microplastics can be transferred through the food chain.

The researchers say that the new technique could be used to identify the sources of microplastic pollution and to track the movement of microplastics through the environment. This information could help to develop strategies to reduce microplastic pollution and protect marine life.

The study is published in the journal Environmental Science & Technology.