Researchers say that about one-third of the barnacles caught in the North Pacific gyre, which is notoriously littered with trash, have plastic material in their digestive system.

Scientists aren’t sure whether eating the plastic refuse hurts the sea creatures, but they say it could fill them up with non-nutritious material.

The open-access journal PeerJ reported Wednesday that at least 267 marine species have been found to eat plastic, including birds, fish and turtles.

Laboratory studies suggest filter feeders such as barnacles eat plastic pellets, but researchers said only three species of invertebrates – sand fleas, Norway lobsters and flying squid – are known to eat plastic in the wild.

Researchers caught two species of barnacles, Lepas anatifera and Lepas pacifica, in the North Pacific gyre, and then dissected them and checked their digestive systems.

The study found that 129 of the 385 barnacles collected had ingested microplastics, which are worn by wind and sea to less than 5 mm in diameter.

Most of those barnacles had only a couple of pellets in their guts, but researchers said 57 had three or more, and one had 30 pellet particles.

Scientists said they found no sign of digestive backup in the samples they collected, but long-term health effects remain unknown.

Researchers said the barnacles don’t eat enough plastic to clean up the litter, and they apparently don’t digest it.

"The barnacles just poop out the plastic & it floats away again," tweeted Miriam Goldstein of the Scripps Institution of Oceanography.

[Image via Agence France-Presse]