Noble gases help humans journey farther

Getting high on xenon

Satisfied with their full outer shells, noble gases are typically monatomic, indifferent to their peers. Despite their nonchalance, though, two of these gases have assisted humans in the far reaches of the planet where oxygen is scarce: from the seafloor to the highest mountain peak.

In May, xenon was used to fuel an expedited 7-day Mount Everest trek.

Discovered in the gunk left over from evaporated liquid air, xenon would later be used in anesthesia, an application inspired by the drunken state of deep-sea divers who breathed air mixtures containing the gas.

Xenon is still sometimes used in medicine. Michael Fries, a chief physician at St. Vincenz Hospital Limburg, studied its neuroprotective properties in animals. It may also boost erythropoietin (EPO), stimulating red blood cell production, though evidence is inconclusive.

Extra red blood cells come in handy at high altitudes, where the body fights for oxygen as atmospheric pressure decreases. Historically, Everest expeditions take more than a month and involve multiple training hikes up and down sections of the mountain to protect against deadly altitude sickness. At-home acclimatization methods have emerged alongside the expansion of the adventure industry; techniques include sleeping with low-oxygen tents draped over the bed and exercising in hypoxic masks.

When Fries heard an interview with Lukas Furtenbach, founder of alpine excursion company Furtenbach Adventures, describing such “cumbersome” preacclimatization, Fries recalled his clinical experience with xenon gas and reached out to the guide. He predicted that xenon could be a game changer for mountaineers, with its potential to promote EPO production and defend “vulnerable tissues like the brain in an environment with little oxygen,” he tells Newscripts in an email.

Furtenbach jumped on Fries’s proposal to test the gas himself.

Fully convinced by how capable he felt inhaling xenon before multiple treks, Furtenbach decided to offer it to his clients. The takers were a team of UK Armed Forces veterans who were on a mission to raise money for charity but who lacked the spare time traditionally needed to climb Everest.

In one of the swiftest summits after at-home acclimatization—which spanned months—the team achieved the ambitious goal of 1 week, including flights, May 16–23.

Fries administered the xenon gas about a week and a half before departure. Whether the team’s success is attributable to xenon “is difficult to say,” Fries says.

Furtenbach tells Newscripts via email that the trek went “perfectly well.” He adds, “It wouldn’t have been possible in a safe way without the xenon,” and the climbers did not use more supplemental oxygen than other Everest climbers do. His company will continue using xenon, and he hopes “the scientists do their job now and progress with the necessary research,” he says. “Seems we are ahead of them at the moment. As it happens often with innovation.”

Going deep with helium

Down from on high to the dark ocean floor: the noble gas helium is used in pressurized diving habitats. These tiny containers can house divers for weeks as they work, doing marine research or installation, maintenance, or salvage of structures like communication cables.

Deep-sea divers have the opposite problem of high-altitude climbers: high pressures force pure oxygen into bodily tissues and make it toxic to breathe. Divers usually breathe a mixture of oxygen and helium called heliox. Nitrogen is used at shallower depths but has a narcotic effect at high pressures—not ideal for working. Helium lacks this feature, and its lower density reduces strain on expanding lungs.

Though it’s safe, there’s a familiar quirk to breathing heliox. Because helium atoms are lighter than oxygen, sound waves travel faster through the gas, increasing their frequencies and lending voices a high-pitched squeak.

Imagine sounding like you’d just inhaled a helium balloon day and night, even while doing serious, dangerous work.

Saturation diver Serge Huber tells Newscripts that it was “a bit of a challenge trying to comprehend” what his partners said on his first underwater jobs, but divers “very quickly get used to the high-pitched voices.”

Both high and low, it seems noble gases have helped humans reach farther.

Please send comments and suggestions to newscripts@acs.org.