The discovery of rocks formed from plastic debris on Brazil's remote Trindade Island has alarmed scientists and highlighted the growing impact of human activity on the Earth's geological cycles. Melted plastic has intertwined with rocks on the island, which is situated 1,140 km (708 miles) from the southeastern state of Espirito Santo and serves as a refuge for turtles.
Fernanda Avelar Santos, a geologist at the Federal University of Parana, said, "This is new and terrifying at the same time because pollution has reached geology." Santos and her team conducted chemical tests to determine the types of plastics found in the rocks, dubbed "plastiglomerates" due to their composition of sedimentary granules and other debris bound together by plastic.
The researchers identified that the pollution primarily originated from fishing nets, a common type of debris on Trindade Island's beaches. Santos explained, "The [nets] are dragged by the marine currents and accumulate on the beach. When the temperature rises, this plastic melts and becomes embedded with the beach's natural material."
Trindade Island is a crucial conservation site for green turtles (Chelonia mydas), with thousands arriving each year to lay their eggs. The only human inhabitants on the island are members of the Brazilian navy, who maintain a base there and protect the nesting turtles. Santos highlighted that the plastic samples were found in a permanently preserved area in Brazil, near where green turtles lay their eggs.