The Arctic Ocean is a final resting place for plastic debris dumped into the North Atlantic Ocean, new research suggests.

A 2013 circumpolar expedition discovered hundreds of tons of plastic debris, from fishing lines to plastic films, ecologist Andrés Cózar of the University of Cádiz in Spain and colleagues report April 19 in Science Advances. While many areas remain relatively unpolluted, the density of plastic trash in the Arctic waters east of Greenland and north of Europe rivals plastic pileups in waters closer to the equator, despite few nearby human populations. Even more plastic probably lurks on the seafloor, the researchers suspect.

Ocean currents carried that plastic northward from the North Atlantic Ocean, the researchers propose. Based on the kind of plastic found, the researchers say the debris probably originated from the U.S. East Coast and Europe. While the study estimates that the Arctic contains less than 3 percent of all global floating plastic, that number will only rise as currents continue carrying pollution poleward, putting Arctic ecosystems at risk.