A series of newly-published studies based on a National Geographic expedition to Mount Everest in 2019 provide a shocking picture of how human activity is impacting the highest point from sea level on Earth. One of the studies even found microplastics just below the summit, at 8,440 meters (approximately 27,690 feet).

"Mt. Everest is somewhere I have always considered remote and pristine," University of Plymouth scientist and National Geographic Explorer Dr. Imogen Napper, who was the lead author on the plastics study, told EcoWatch in an email. "To know we are polluting near the top of the tallest mountain on earth is a real eye opener – we need to protect and care for our planet."

Microplastics at the Top of the World

Napper's study, published in the journal One Earth Friday, found microplastics in every snow sample taken from Mount Everest. The findings join a growing body of research showing the extent of microplastic pollution in even the most remote corners of the planet.

"These are the highest microplastics currently ever discovered," Napper told EcoWatch. "Although it sounds exciting, this means that microplastics have been discovered from the depths of the ocean all the way to the highest mountain on earth."

There has been growing awareness in recent years of the buildup of trash on Mount Everest left behind by tourists and climbers. In 2019, the Tibet Autonomous Region Sports Bureau said it removed 9.3 tons of waste, and China closed its Everest base camp to tourists to prevent more pollution. Some media outlets have even begun to refer to the mountain as the "world's highest garbage dump."

However, Napper's study is the first to focus on the accumulation of microplastics on the mountain specifically. Microplastics are plastics less than five millimeters in length that typically slough off of larger plastics as they degrade. Their small size means they are easily ingested by animals by mistake and are also extremely difficult to clean up.

Napper's team found more microplastics collected near the base camp, where climbers tend to congregate. But they still found five microfibers at the mountain's "balcony," the highest point they studied. Those fibers numbered one clear acrylic fiber, one red polyester fiber and three blue polyester fibers.

In general, many of the microplastics found on Everest were fibers that could have been brought by climbers.

"Samples collected on the mountain and in the valley below it revealed significant quantities of polyester, acrylic, nylon, and polypropylene fibres," Napper told EcoWatch. "The materials are increasingly being used to make the high performance outdoor clothing commonly used by climbers, as well as the tents and climbing ropes used in attempts to climb the mountain."

However, other studies have shown that microplastics can be carried to remote environments by the atmosphere. A 2019 study found that plastics were being lifted in the air and deposited as snow in the Arctic and the Alps. Napper said similar mechanisms could be bringing the plastics to Everest.

"[T]he microplastics may have been transported from lower altitudes by the extreme winds which regularly impact the mountain's higher slopes," Napper said.

So how can we keep Everest, and other remote environments, plastic free? Napper argued that, while reducing plastic use and improving recycling were both important, it is also crucial to develop new materials. This is particularly the case for the kind of specialized gear used to explore remote areas.

"There are a lot of promising developments in industry at the moment. We need to keep up the momentum, and ensure that athletic gear is tested and evaluated before use," Napper told EcoWatch. "Solutions need to deliver a positive account, not create future issues."

Glaciers Melting Into Air

Napper's article was just one of at least 16 that came out of the 2019 National Geographic and Rolex Perpetual Planet Everest Expedition. That expedition brought 10 research teams including 34 international and Nepali scientists to Everest from April and June of last year in order to study the impacts of human activity on the mountain.

In addition to the accumulation of microplastics, studies focused on the impacts of the climate crisis on the mountain. One, published in iScience, detailed how global warming is actually increasing the oxygen available to human climbers as warmer temperatures have increased air pressure. Another, published in OneEarth, documented how Everest's glaciers have thinned by more than 100 meters (approximately 328 feet) since the 1960s. Not only that, but the ice loss is accelerating, and glaciers are losing mass even at high altitudes.

Study leader and University of St. Andrews glaciologist Dr. Owen King said the melting of the higher glaciers was the "biggest surprise" from the results. His team measured thinning at the 5,700 meter (approximately 18,702 foot) Khumbu icefall and the 6,000 meter (approximately 19,685 foot) Rongbuk and Rongbuk East glaciers.

"The conditions found at this altitude are usually considered ideal for snow and ice accumulation, but our data suggest that they have now become more susceptible to ice melt," King said in an email to EcoWatch.

The melting of mountain glaciers is a big deal, because they are an important source of water to surrounding communities.

"Continued and, as we have shown, accelerating ice loss raises concerns about the sustainability of the supply of glacial meltwater, particularly at times of the year when monsoon rainfall cannot provide a backup, or in times of drought," King said.

Understanding how climate change will impact mountain glaciers is the ultimate goal of the Perpetual Planet expeditions, of which the Everest trip was the first.

"The 2019 National Geographic and Rolex Perpetual Planet Everest Expedition was selected as a fantastic opportunity to support ground breaking research that fills a critical data gap in our understanding of how mountain systems are changing," Nicole Alexiev, vice president of science and innovation at the National Geographic Society, told EcoWatch in an email. "High mountain glaciers serve as the world's water towers, storing and providing water resources for 1/5 of the global populations. Despite the importance of high mountain systems, there is very little research conducted above 5,000m [approximately 16,404 feet] – especially interdisciplinary research – so we were excited to support this expedition which aimed to examine the world's highest mountain and its glaciers using expertise from the disciplines of biology, geology, glaciology, meteorology, and mapping."

Future expeditions will explore the Andes and western Canada, where mountain glaciers supply water to Santiago, Chile and the Columbia and Fraser river watersheds.