A new study has found that almost three-quarters of fish in the Northwest Atlantic Ocean had plastic in their stomachs.
Scientists at NUI Galway found that 73% out of 233 deep water fish had ingested plastic particles known as microplastics.
Microplastics are fragments created when larger plastic items break down in the ocean, while they can also originate from plastic fibres from clothing or the microbeads found in some cosmetic products.
The NUI Galway study - which has been published in the Frontiers in Marine Science journal - found that the level of plastic ingested by fish is one of the highest frequencies of microplastic in fish found anywhere in the world.
Researchers say the fish are likely exposed to microplastics when they migrate to the surface at night to feed on plankton.
They say that the sampled fish may have originated from a "particularly polluted patch" of the ocean.
Dr Tom Doyle, a co-author of the study, explained: “While there is clearly a concern that the ingestion of microplastics with associated toxins may have harmful effects on these fishes, or even the fishes that feed on them, our study highlights that these seemingly remote fishes located thousands of kilometres from land and 600 metres down in our ocean are not isolated from our pollution.
"Indeed, it’s worrying to think that our daily activities, such as washing our synthetic clothes in our washing machines, results in billions of microplastics entering our oceans through our waste water stream that may eventually end up in these deep sea fishes.”
The study's lead author, Alina Wieczorek, added that they plan to further investigate the impact of plastics on ocean creatures.
Microplastics can cause internal physical damage to fish, and there are fears that toxins could be transferred to humans and other animals that eat affected fish.