Most of the plastic bottles washing up on the rocky shores of Inaccessible Island, aptly named for its sheer cliffs rising from the middle of the South Atlantic, probably come from Chinese merchant ships, a study published on Monday said. The study offers fresh evidence that the vast garbage patches floating in the middle of oceans, which have sparked much consumer hand-wringing in recent years, are less the product of people dumping single-use plastics in waterways or on land, than they are the result of merchant marine vessels tossing their waste overboard by the ton.

The authors of the study published in the Proceedings of the National Academy of Sciences, or PNAS, collected thousands of pieces of waste during visits to the tiny island in 1984, 2009 and again in 2018. The island is located roughly midway between Argentina and South Africa in the South Atlantic gyre, a vast whirlpool of currents that has created what has come to be known as an oceanic garbage patch.

While initial inspections of the trash washing up on the island showed labels indicating it had come from South America, some 2,000 miles (3,000 kilometers) to the west, by 2018 three-quarters of the garbage appeared to originate from Asia, mostly China. Many of the plastic bottles had been crushed with their tops screwed on tight, as is customary on board ships to save space, said report author Peter Ryan, director of the FitzPatrick Institute of African Ornithology at the University of Cape Town in South Africa.

Around 90 percent of the bottles found had been produced in the previous two years, ruling out the possibility that they had been carried by ocean currents over the vast distance from Asia, which would normally take three to five years.

Copyright Agence France-Presse, 2019