Scientists also said they had for the first time discovered marine microplastics, tiny pieces of plastic often used as scrubbers in facial cleansers and toothpastes, in the ocean off the Antarctic Peninsula.

He said microplastics, which reach oceans after passing through wastewater treatment plants, were also found during the national expedition to the Arctic last year.

"That was somewhat understandable as the northern seas are not far from human activity, but it's surprising that they also appeared in the Antarctic," he said.