Even the tallest peak in the world is not immune to microplastic pollution, it seems. In a new study published on 20 November in One Earth, scientists show evidence of microplastics near the summit of Mount Everest (1).
Microparticles are minuscule plastic particles (less than 5 mm) that often go undetected by the human eye and are now found ubiquitously. Microplastics were previously reported in soils, rivers, lakes, and oceans in widespread regions as far as the Arctic, and even in the human gut. Scientists have also reported of plastic debris in the remote ― previously pristine ― mountaintops of the Swiss Alps, French Pyrenees, and North American Rocky Mountains. And now, microplastics have made it to the tallest peak in the world: Mount Everest.
The team of researchers analyzed snow samples from 11 locations on Everest, ranging from 5,300 metres to 8,440 metres high collected by a National Geographic expedition in 2019. A significant concentration of microplastics was found in every sample. The authors reported an average of 30 microplastic particles per litre of water in the snow samples and 119 particles per litre in the most contaminated sample.
Many of these microplastics are shed from clothing and equipment made from synthetic fabrics, including the technical clothing, tents and ropes used by climbers, which is likely where most of the microplastic pollution on Everest comes from, the scientists say. Microplastic particles can also be carried from further afield by the wind.
“The samples showed significant quantities of polyester, acrylic, nylon, and polypropylene fibres”, said lead author Dr Imogen Napper, a marine scientist at the University of Plymouth in the UK, in a press release. “Those materials are increasingly being used to make the high-performance outdoor clothing climbers use as well as tents and climbing ropes, so we highly suspect that these types of items are the major source of pollution rather than things like food and drink containers”.
The highest concentrations were, unsurprisingly, found Base Camp, which is where climbers and trekkers spend the most time – in some cases, a month or longer. However, the researchers also discovered evidence of microplastics as high up as 8,440 meters above sea level, just below the summit, which is the highest altitude microplastics have ever been recorded.
“I didn’t know what to expect in terms of results, but it really surprised me to find microplastics in every single snow sample I analyzed”, Nappier added. “Mount Everest is somewhere I have always considered remote and pristine. To know we are polluting near the top of the tallest mountain is a real eye-opener”.
“With microplastics so ubiquitous in our environment, it’s time to focus on appropriate environmental solutions,” she said. “We need to protect and care for our planet.”
“Currently, environmental efforts tend to focus on reducing, reusing, and recycling larger items of waste. This is important, but we also need to start focusing on deeper technological solutions that focus on microplastics, like changing fabric design and incorporating natural fibres instead of plastic when possible”.
(1) Napper, I. E. et al. Reaching New Heights in Plastic Pollution—Preliminary Findings of Microplastics on Mount Everest. One Earth (2020). DOI: 10.1016/j.oneear.2020.10.020