On a remote island, scientists find ‘worrying’ finding

Few places in the world are as isolated as Trindade Island, a volcanic outcrop a three- to four-day boat ride off the coast of Brazil. That’s why geologist Fernanda Avelar Santos was shocked to discover an alarming sign of human impact on a normally pristine landscape: rocks formed from extreme plastic pollution floating in the ocean. Santos first found the plastic rocks in 2019 when he went to the island to research his doctoral thesis on a completely different topic: landslides, erosion, and other “geological hazards.”

While working near a reserve known as Turtle Beach, the world’s largest breeding ground for endangered green turtles, he stumbled upon a large ledge of gorgeous blue-green rocks. Intrigued, he had taken some back to his lab after a two-month expedition. After analyzing them, he and his team identified the samples as a new type of geological formation, combining the materials and processes Earth has used for billions of years to form rocks with a new component: plastic debris.

“We concluded that humans are now acting as a geological agent, influencing processes that were previously entirely natural, such as rock formation,” he told AFP.

“This is consistent with the idea of ​​the Anthropocene, about which scientists today talk a lot: the geological epoch of human influence on natural processes on the planet. This type of stone will be preserved in the plastic geological record and leave its mark on the Anthropocene.”

paradise island

Santos, a professor at the Federal University of Paraná in southern Brazil, said the finding left him “concerned” and “sad”. He describes Trinidad as “paradise”: a beautiful tropical island whose remoteness makes it a sanctuary for various species – seabirds, fish only found there, nearly extinct crabs, green turtle. The only human presence on the South Atlantic island is a small Brazilian military base and research center.

“Great,” he said.

“So it was even more terrifying to find something like this on one of the most ecologically important beaches.”

He returned to the island late last year to collect more samples and further investigate the phenomenon. Continuing his research, he discovered that since 2014, similar rock-like plastic formations had been previously reported in places like Hawaii, the United Kingdom, Italy, and Japan. But Trindad Island is the most remote place they’ve ever found on the planet, he said. He fears that as the rocks erode, they will release microplastics into the environment and further contaminate the island’s food chain.

‘Paradigm shift’

The study, conducted by him and his team, was published in September in the journal Nature. Marine Pollution Bulletin, divided a new type of “stone” found all over the world into several types: “plastiglomerates” similar to sedimentary rocks; “pyroplasty” similar to clastic rocks; and “plaststones”, a previously unknown type, similar to volcanic rocks formed by a lava flow.

“Marine pollution is causing a paradigm shift in how we think about rocks and sediments,” his team wrote. “Human interference is now so pervasive that it is necessary to question what is truly natural.”

The main component in the rocks Santos found were the remains of fishing nets they discovered. But he said ocean currents have also brought large quantities of bottles, household waste and other plastic debris to the island from around the world. Santos said he plans to make the subject his main research area.

“Trindad is the cleanest place I’ve ever seen,” he said. “Seeing how vulnerable we are to the litter polluting our oceans shows how widespread this problem is around the world.”