Scientists have long assumed Antarctica to be largely free from plastic pollution. A research team from the University of Hull has made a worrying discovery.
Catherine Waller and a team from the British Antarctic Survey did not know what to expect when they began their work researching the southernmost tip of the planet. Considered to be a pristine wilderness in comparison with the rest of the world, Antarctica had been assumed by colleagues and academics to be relatively free from plastic pollution. They were wrong.
What are microplastics?
Microplastics are particles of plastic less than 5mm in diameter and are present in many everyday cosmetic items such as toothpaste and shampoos as well as clothing, and can also result from the breakdown of macroplastic or larger plastic items. “Although Antarctica is very remote there is still human activity from research bases, ships, fishing, and, increasingly, cruise ships,” says Catherine, an expert in ecology and marine biology at the University of Hull. “I began to think if we have increasing numbers of people going to Antartica, what effect is this having on the levels of microplastics?”
Knowing how many people travelled there yearly, the team used published rates of plastic use and production per person in order to estimate microplastic levels. They took samples from a site on King George Island in Antarctica and found microplastic levels were five orders of magnitude higher than expected – 100,000 times higher than first predicted.
Due to the Antarctic’s unique ecosystem and ocean circulation pattern, microplastic levels could have a major impact on the area. “The findings raised the possibility that plastic originating from outside the region may be getting across the Antarctic Circumpolar Current, historically thought to be almost impenetrable until now.” The research highlights the urgent need for a co-ordinated effort to monitor and assess the levels of microplastics around the Antarctic continent and Southern Ocean and formed the basis of a policy paper presented at the 2018 Antarctic Treaty Consultative Meeting, the body that governs the Antarctic.
The results led to questions. Where did the microplastics come from? What effect could this level of microplastics have on the fragile ecosystem? This pioneering research had triggered discussion and, most importantly, action.
Looking forward
Concern is growing about pollution from floating plastic debris, which can be become entangled with or ingested by wildlife. In contrast, pollution by microplastics has received little scientific or regulatory attention. It’s estimated that up to 500kg of microplastic particles from personal care products and up to 25.5 billion clothing fibres enter the Southern Ocean per decade as a result of tourism, fishing and scientific research activities. While this is negligible at the scale of the Southern Ocean, the researchers say it may be significant at a local scale.
Given the trailblazing nature of this research very little is actually known about the effects of microplastics on Antarctica’s fragile ecosystem. Research on plastic migration through the food web in Antarctica is just emerging. “Earlier this year a group of Australian researchers published some interesting data,” says Catherine. “They found krill were eating microplastics and breaking them down into nano-plastics. Ingesting microplastics could mean that krill might not be able to reproduce as well as before, or it could alter their nutrient levels, both of which would have a major knock-on effect on those animals that eat krill.” Catherine’s focus for on-going research is following microplastics through the whole marine plastic cycle in Antarctica.
In the meantime, she is establishing best practice. With the developing nature of the research, a unified method of reporting has yet to be agreed upon. “Some report the number of particles per litre of water, while others might report the weight of the microplastics by metre cubed. This makes results incomparable.”
So, in collaboration with the Scientific Committee on Antarctic Research, Catherine and more than 56 scientists, NGOs and policy makers have come together to produce best practice advice for future researchers.
Back home, the UK Government is banning microplastic use in cosmetics and personal care products. “There seems to be momentum from the producers and consumers to cut down plastic use,” says Catherine.
We may have only just skimmed the surface of microplastic research, however, Catherine Waller, the University and the British Antarctic Survey are dedicated to following the trail in order to understand what effect mankind’s microplastic waste is having on the marine plastic cycle in Antarctica.
