Microplastics were found for for the first time in fresh snow in Antarctica, which could accelerate the melting of snow and ice and pose a threat to “health” of the continent's unique ecosystems.
The tiny plastics – smaller than a grain of rice – have previously been found in the sea ice of Antarcticand in surface waters. But this time is the first time fresh snowfall has been reported, according to the researchers.
The study, conducted by Canterbury University PhD Alex Aves and supervised by Dr Laura Revell, was published in the scientific journal The Cryosphere.
Aves collected snow samples from the Ross Ice Shelf in late 2019 to determine if they had been transported microplastics from atmosphere to χιόνι. Until then, there were few studies related to microplastics in Antarctica.
"We were optimistic that we would not find microplastics in such a pristine and remote area," Revell said.
He instructed Aves to also collect samples from Scott Base and the streets of McMurdo Station - where microplastics have been detected in the past - so "we will have at least some microplastics to study," Revell said.
But this was unnecessary because plastic particles were found in each of the 19 samples taken from the Ross Ice Shelf.
"It's incredibly sad, but finding microplastics in the fresh snow of Antarctica underscores the extent of plastic pollution even in the most remote parts of the world," Aves said.
Aves detected an average of 29 microplastic particles per liter of melted snow, which is higher than the marine concentrations we reported before the Ross Ice Shelf and the Antarctic ice sheet.
The samples taken from the scientific bases on Ross Island, at base Scott and from McMurdo Station had higher concentrations – nearly three times that of the outlying areas.
Thirteen different types of plastic were found, the most common being PET - the plastic most commonly used to make soft drink and laundry bottles.
Atmospheric modeling has shown that they may have traveled thousands of miles through the air, but it is equally possible that the presence of humans in Antarctica has created a microplastic "imprint", according to Revell.