(BBC) – A remote island in the southern Atlantic Ocean has helped reveal the scale of the problem of plastic waste facing our seas.
Some 75% of bottles washed ashore on Inaccessible Island, in the South Atlantic, were found to be from Asia – with most made in China.
Researchers said most of the bottles had been made recently, suggesting they had been discarded by ships.
An estimated 12.7 million tonnes of plastic end up in our oceans each year. But this figure just covers land-based sources.
The team from South Africa and Canada, writing in the Proceedings of the National Academy of Sciences (PNAS), said that it had been assumed that most of the debris found at sea was coming from the land.
However, the scientists said the evidence suggested otherwise.
“When we were [on the island, called Inacessible Island] last year, it was really shocking how much drink bottles had just come to dominate,” explained lead author Peter Ryan, director of the FitzPatrick Institute of African Ornithology at the University of Cape Town.
During litter surveys on the island, which is a World Heritage Site, the scientists examined 3,515 debris items in 2009 and 8,084 debris items in 2018.
Polyethylene terephthalate (PET) drinking bottles were the most common type of debris and had the fastest growth rate among debris, increasing at 14.7% each year since the 1980s.