An environmental group is asking the Nepal government to consider installing portable toilets on Mount Everest for climbers caught short at the roof of the world.
Eco Himal says the thousands of trekkers who set off from the South Base Camp in Nepal each year would do a better job of keeping the place clean if they and their porters had somewhere civilised to go when nature called.
"Human waste is a problem, of course," said the group's director, Phinjo Sherpa. "I am merely suggesting that if we have public toilets they can be used."
Many groups bring expedition toilet cans, but Phinjo Sherpa said porters were often left with little choice but the nearest snowdrift.
Environmental activists say Everest is littered with the detritus of past expeditions, including human waste and mountaineers' corpses, which can take decades to decompose because of the extreme cold.
Phinjo Sherpa said installing the toilets would be discussed as part of a wider waste management plan being prepared by the government that would encompass popular peaks throughout the Everest region.
"If there could be two or three toilets that would be good but this is just at the planning phase. We will have to decide what is a good idea and what isn't," he said.
However, the idea has been rejected by some of Eco Himal's partners within the Nepal-based climbing community.
"The ice moves around a lot during the year. If you built toilets at the base camp, the ice would shift and the structures would fall down," said Wangchhu Sherpa, president of the Everest Summiteers Association.
Climbers spend tens of thousands of dollars trying to reach the 8,848-metre (29,028-foot) summit of Everest, but campaigners say few pay much attention to the rubbish they leave behind.
There is no official figure on how much trash has been left on the mountain, but the debris of 50 years of climbing has given Everest the name of the world's highest dumpster.
The privately-funded Eco Everest Expedition, a Nepal-based coalition of environmentalists campaigning to keep the mountain clean, has collected more than 13 tonnes of garbage, 400 kilos of human waste and four bodies since 2008.
Government officials say Everest trekkers are expected to bring down all their rubbish themselves.
Expeditions currently have to fork out a 4,000-dollar deposit, which is refundable once they show they have brought back everything they took onto the mountain. But the rules are impossible to enforce, say campaigners.
Wangchhu Sherpa said at least 10 tonnes of rubbish remained on the mountain. He is calling for the government to blacklist tour groups who cannot account for all their equipment and belongings when they return from Everest.
Nepal's Sherpa people, who are Buddhists and believed to be of Tibetan origin, make up most of the population in the Everest region and have long revered the world's highest peak as sacred.
Almost 4,000 people have attempted to climb Mount Everest since Edmund Hillary and Tenzing Norgay became the first people to conquer the world's highest peak in 1953.
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