New research by a University of Canterbury doctoral student has discovered the presence of microplastics in Antarctic snowfall, shattering the myth that the large southern continent is relatively untouched by humans.
Alex Aves, a PhD student at the University of Canterbury, made the discovery after collecting snow samples on a trip in 2019 and the results have just been published in a scientific journal The cryosphere.
Microplastics, pieces of plastic smaller than grains of rice, have even been found in samples taken from sites far from human occupation.
Avès says morning report said the source of these microplastics included the air that carries them and the human footprint.
“It looks like some of the airflow went through those bases, and so we established that human footprint there. So that’s one of the most likely sources.
“The other source is this long-range transport. We did modeling to see how far they could have come and our models showed they could have come from over 6,000 kilometers above the Southern Ocean. , so they may have been picked up from the ocean, carried through the air, and deposited in this snowfall that we then collected.”
Aves, who recently earned a master’s degree in Antarctic studies, said the samples collected by the team were about 20 km from the bases.
Snow samples were taken from 19 sites in the Ross Island region of Antarctica and found microplastics in all of them.
“We really didn’t expect to find them, especially in those remote samples we took. It was a shock, especially because we sampled very fresh snow.”
The paper found an average of 29 microplastic particles per liter of melted snow, which is higher than previously reported marine concentrations in the surrounding Ross Sea and Antarctic sea ice.
“We know from previous research that microplastics have a negative impact on health, and so once they enter the food chain they have the potential to clog digestive systems. They can also introduce other chemicals toxic in animals which obviously the more exposure to these harmful things, the greater the negative impact.
“We kind of have to figure out how long they’ve actually been settling there.”
She said research in the future will focus on “how far we can actually find terrestrial plastics”.