New research from a University of Canterbury PhD candidate has uncovered the presence of microplastics in Antarctic snowfall, shattering the myth that the great southern continent is relatively untouched by humans.
Photo: goinyk/123RF
University of Canterbury PhD student Alex Aves made the discovery after collecting snow samples during a 2019 trip and the findings have just been published in scientific journal The Cryopshere.
Microplastics, pieces of plastic smaller than grains of rice, were even found in samples taken at remote sites away from human occupation.
Aves told Morning Report said the source of those microplastics included air carrying them, and human footprint.
"It does look like some of the airflow did pass by those bases, and so we have established that human footprint down there. So that is one of the most likely sources.
"The other source is that long-range transport. We did do some modelling to see how far they could have come and our models did show that they could have come from over 6000 kilometres away from over the Southern Ocean, so they may have been picked up out of the ocean, transported through the air and deposited in that snowfall that we then collected."
Aves, who recently graduated with a Master of Antarctic Studies degree, said the samples the team collected were about 20km away from the bases.
Snow samples were collected from 19 sites across the Ross Island region of Antarctica and found microplastics in all of them.
"We really weren't expecting to find them, especially in those remote samples we took. It was quite a shock, especially because we did sample very fresh snow."
The paper found an average of 29 microplastic particles per litre of melted snow, which is higher than marine concentrations reported previously from the surrounding Ross Sea and in Antarctic sea ice.
"We do know from previous research that microplastics do have a negative impact on health, and so as soon as they make their way into the food chain, they have the potential to clog digestive systems. They can also introduce other toxic chemicals into animals which obviously the more exposure to these harmful things, the more negative impact.
"We need to kind of figure out how long they have been actually establishing down there."
She said research into the future would be looking at "how far away we can actually find Earth plastics".
