There’s a lot to know about how plastic waste moves around the marine environment, but researchers are coming up with new ways to track its path. A study by Italian scientists has revealed how lobsters digest plastic particles, finding that their stomachs actually grind them into tiny pieces that can pose a danger to smaller organisms in the food chain.
Millions of tons of plastic waste are washed into the sea every year, and under the corrosive power of the ocean, they are broken down into smaller pieces that are difficult to track. However, studies tell us that they cause hemangiomas in fish, that turtles and birds mistake their smells for food, and that underwater “avalanches” drive them into the deep sea, where their effects on underwater life are largely unknown.
Among these deep-sea creatures is the Norwegian lobster Nephrops norvegicus, which perches on the sea floor. Scientists at the University of Politics in Marche, Italy, and the University of Cagliari conducted a new study to try to determine what happens when these organisms ingest plastic waste.
The study builds on previous research that determined that lobsters do ingest tiny pieces of plastic called microplastics, while other crustaceans can break down plastic particles into smaller pieces during digestion. So the researchers collected lobsters from the Mediterranean to see if a similar process might be at work.
The team’s observations found that larger pieces of plastic tended to get stuck in the lobster’s stomach. Smaller particles enter the so-called “gastric grinder”, where food is ground down by small plates that are calcined. This breaks down these small particles into smaller particles, which are thought to be excreted by lobsters and released into the ocean.
“These findings highlight the existence of a new and exotic “secondary” microplastic, which was introduced into the environment by biological activities and may represent an important way for plastic degradation in a hidden and stable environment like the deep sea,” the study authors wrote.
The study was published in the journal Environmental Science and Technology.