A study of marine life living more than 2,000 m under the North Atlantic Ocean has revealed that half of these deep-sea creatures contain microplastic materials.
The Scottish Association for Marine Science
Microscopic plastics
A microscopic trace of polyester taken from one of the sample species.
The Scottish Association for Marine Science (SAMS) based in Oban, Scotland, took samples of deep-sea starfish and sea snails from the Rockall Trough, a sedimentary basin to the west coast of Ireland, and found traces of polymer in 48 per cent of their catch.
This high concentration of plastics ingested is comparable to the results of plastics found in shallower sea-dwellers, the team reported in the journal Environmental Pollution.
Microplastics are anything plastic that is under 5 mm in size and are especially sinister as they can be passed up the food chain when consumed by animals that are preyed upon.
This is the first study of its kind to quantify microplastic ingestion by deep-sea invertebrates.
Polyester and polyethylene were among the most prominent microplastic materials found in the sea creatures.
Lead author on the paper ‘Microplastic pollution identified in deep-sea water and ingested by benthic invertebrates in the Rockall Trough, North Atlantic Ocean’ is Winnie Courtene-Jones, a University of the Highlands and Islands PhD researcher based at SAMS.
"Microplastics are widespread in the natural environment and present numerous ecological threats, such as reducing reproductive success, blocking digestive tracts and transferring organic pollutants to organisms which eat them," said Courtene-Jones. "More than 660 marine species worldwide are documented to be affected by plastics.
“There is much evidence of microplastics around coastal waters but little is known about the extent of plastic pollution in the deeper ocean. The deep sea is the largest, but also the least explored part of the planet and may be the final sink for plastics. More work is needed on the wider ocean environment to understand the long-term fate of marine plastics."
Brittle star fish
The study found the quantity of ingested microplastics differed between species but did not relate to the size or feeding habits of the species.
SAMS Deep Sea Ecologist Dr Bhavani Narayanaswamy, said: "No longer ‘out of sight, out of mind’, research into microplastics is rapidly increasing in importance. We are attempting to establish not only how widespread they are, but also how and where they accumulate in animals, and ultimately the impact that they may have on the health of humans."
The sampling was done in June 2016 during the annual Extended Ellett Line research cruise on board the RRS Discovery.
