It is one of the most isolated places in the world, but it is not spared from the pollution of the oceans: on the island of Trindade, 1,200 km from the coast of Brazil, crusts of plastic waste, or ” plasticrocks”, formed in rocks.
A disturbing discovery for geologist Fernanda Avelar Santos, who never imagined finding such evidence of human impact on the environment in this tropical “paradise”, a volcanic outcrop whose access is authorized only to the military and scientists. , and after three or four days of navigation.
She first saw these greenish crusts on about 12 m2 of rock formations in 2019, on Turtle Beach, the world’s largest ecological reserve for the nesting of green sea turtles, an endangered marine species.
At the time, this researcher from the Federal University of Parana (south) had come on an expedition to the island for her thesis on a totally different theme, landslides, erosion and other “ecological risks”.
But this discovery of rocks formed by the accumulation of plastic waste intrigued her so much that she brought back a sample to analyze it in her laboratory.
His team then identified a new type of geological formation, with an intruder in the middle of the mineral components that are usually found in rocks: plastic waste, which becomes embedded in natural materials.
Most of the plastic organisms found in the samples taken are the remains of fishing nets, but the currents have also brought a large quantity of bottles and other household waste to the island.
“We have concluded that human beings are now geological agents, having an impact on processes that previously were completely natural, such as the formation of rocks,” she explains to AFP.
“This type of plastic waste in rock formations will remain in the records as a symbol of the Anthropocene, this concept of a geological era in which humans have an influence on nature”, insists the researcher.
She describes the island of Trindade as a “paradise”. Its isolation makes it a sanctuary for all kinds of endangered species, such as seabirds, fish, crustaceans or the green turtle.
The only trace of human presence: a small military base and a scientific research center, 1,200 km from the coast of the state of Espirito Santo (southeast).
“It’s a wonderful place, and that’s what makes it even more terrifying to find such things on such an ecologically important beach,” she says.
Fernanda Avelar Santos returned to the island last year to collect more samples and now plans to make “plasticrusts” her main research subject.
“Marine pollution has caused a paradigm shift for the concepts of rock formations and sedimentary deposits,” reads an article published in September by the Brazilian geologist and her team in the scientific journal Marine Pollution Bulletin.
Other rock formations containing plastic had already been identified since 2014, in Hawaii, Great Britain, Italy or Japan.
But they had never been found in such an isolated place.
“It’s the most protected place I know,” says the researcher, who fears that the erosion of these rocks will cause a leak of plastic microorganisms into the ocean, enough to contaminate the food chain of the ocean. ‘island.
“The island of Trindade is in the middle of the Atlantic, where there are shipping routes, sea currents. Although it is very protected, it is vulnerable to pollution from the oceans, which reflects the extent of this problem on a global scale”, she summarizes.
03/21/2023 05:14:18 – Rio de Janeiro (AFP) – © 2023 AFP
