Microplastics Entering Marine Creatures' Body via Gills

A new research finds that crabs and other higher marine organisms aren't just ingesting tiny bits of plastics, but are even "breathing" them.

According to researchers at the University of Exeter, microplastics enter the organism's body via gills. What's worse is that these extremely tiny bits of plastic, when drawn through the respiratory system, take six times longer duration to be expelled from the body than the ingested bits.

Recently, Australian researchers found that millions of tons of oceanic trash had gone missing. Researchers had said that this missing plastic might have entered the oceanic food chain.

"Many studies on microplastics only consider ingestion as a route of uptake into animals. The results we have just published stress other routes such as ventilation. We have shown this for crabs, but the same could apply for other crustaceans, molluscs and fish - simply any animal which draws water into a gill-like structure to carry out gas exchange," said Dr Andrew Watts of Biosciences at the University of Exeter.

Water waves and sunlight break down plastics into fine bits. These particles are smaller than 5mm and pose significant threat to marine life. 

For the present study, researchers used fluorescently labelled polystyrene microspheres. The dyed plastic bits helped researchers find how the plastic was ingested and retained by the shore crab, Carcinus maenas.

The team found that most microspheres were retained in the foregut of the crab.

The study was funded by CleanSeas and is published in the journal Environmental Science and Technology.

"This is a human issue. We have put this plastic there, mostly accidently, but it is our problem to solve. The best way to do this is to reduce our dependency on plastic. It comes back to the old phrase: reduce, reuse and recycle," Watts added in a news release.