In 1984, 2009, and 2018, researchers made the trek to Inaccessible Island, which is very near a subtropical gyre where floating debris accumulates, to study the plastic debris that ended up on the island and try to figure out where it had originated.
While initial inspections of the trash washing up on the island in the 1980s showed labels indicating the trash 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, reports Phys.org.
After three decades of research and study, the researchers published their findings on Monday in the Proceedings of the National Academy of Sciences where they write that “most plastic debris floating at sea is thought to come from land-based sources, but there is little direct evidence to support this assumption.”
Many of the plastic bottles the scientists found had been crushed with their tops screwed on tight, as is customary onboard ships to save space, said the report’s author Peter Ryan, director of the FitzPatrick Institute of African Ornithology at the University of Cape Town in South Africa.
Nearly 90 percent of the bottles found in 2018 had been produced within the previous two years by Chinese manufacturers, ruling out the possibility they had traveled great distances from Asia in the ocean currents – which would normally take three to five years. This finding was significant. Asian fishing vessels were ruled out because the numbers has remained stable since the 1990s
However, the recent manufacture dates indicate that very few of the bottles could have drifted from Asia, and presumably are dumped from ships, in contravention of the International Convention for the Prevention of Pollution from Ships regulations.
The number of Asian, and in particular, Chinese cargo vessels has increased dramatically in the Atlantic. This led the researchers to conclude that the bottles must come from merchant vessels, which toss them overboard rather than dumping them as trash at ports.
“It’s inescapable that it’s from ships, and it’s not coming from land,” Ryan told AFP. “A certain sector of the merchant fleet seems to be doing that, and it seems to be largely an Asian one,” he said.
Inaccessible Island is aptly named
About 6 million years ago, Inaccessible Island was an active volcano. Its central area is a dissected plateau reaching 449 meters (1,473 feet) above sea level at the summit of Cairn Peak. It is fringed with sheer sea cliffs and only a few boulder beaches, which made generations of sailors wary of difficult landings and inhospitable terrain.
We owe the name of the island to Captain d’Etchevery, of the French ship Etoile du Matin, who, when he failed to land on the island in 1778, coined the name ‘Inaccessible’ rather than “Ile de Etchevery.”
In 2004 Inaccessible Island became a World Heritage Site in recognition of its importance as a wilderness of international significance, particularly for its rare land and sea bird species. It is known as the “Gough and Inaccessible Islands World Heritage Site.”