The moon’s hidden toxic side could prove troubling for future colonists

5 Jul 2018

Lunar module pilot James Irwin works at the Lunar Roving Vehicle during the Apollo 15 mission. Image: NASA

It turns out that the surface of the moon can wreak havoc on the human body, but ESA scientists are trying to figure out how to tackle it for future crewed missions.

It has been nearly half a century since a human walked on the moon. With a potential bounty of minerals there for us to use – not to mention it being a potential launch pad for interplanetary travel – we are once contemplating sending human crews back up there.

However, one little-discussed problem with travelling to the moon is the problem of lunar dust, a thick powder that clings to nearly everything and can cause a number of problems to any humans that encounter it.

When the Apollo astronauts returned to Earth, Neil Armstrong et al commented that the dust that clung to their suits would make their eyes water, their throats sore and give them nasal congestion, possibly for days on end.

This led to it being given the nickname ‘lunar hayfever’ by Apollo 17 astronaut Harrison Schmitt.

But what is the dust made from, and how toxic is it?

Eugene Cernan covered in moon dust

NASA astronaut commander of the Apollo 17 mission, Eugene Cernan, caked in moon dust. Image: NASA

A challenging problem

For starters, the lunar dust has silicate in it, a material commonly found in volcanic regions of Earth and which has proven seriously harmful to miners who inhaled it.

On the moon, this becomes a lot more problematic not only for the humans that inhale it, but their spacesuits as well.

While appearing like a fine powder, each of those granules is razor-sharp, resulting in it being abrasive enough to eat away layers of the astronauts’ spacesuit boots, as well as destroying the vacuum seals of Apollo sample containers.

In the moon’s low gravity, these tiny, sharp particles – 50 times smaller than a human hair – stay suspended for longer and penetrate more deeply into a lung.

However, researchers from the European Space Agency (ESA) are now trying to understand how toxic the dust really is, given we’re eager to get back up there.

“We don’t know how bad this dust is. It all comes down to an effort to estimate the degree of risk involved,” said Kim Prisk, a pulmonary physiologist from the University of California involved in this research.

The team will examine the potential damage of inhaled moon dust, potentially confirming other research that has shown lunar soil simulants can destroy lung and brain cells after long-term exposure.

Given the rarity of actual moon dust, the team will use silicate dust mined from a volcanic region in Germany, but the need to grind this material to make the dust will take away the familiar sharpness seen in real moon dust.

Moon dust isn’t entirely all bad news for future moon colonisers, however, as the team’s science adviser, Aidan Cowley, explained: “You can heat it to produce bricks that can offer shelter for astronauts. Oxygen can be extracted from the soil to sustain human missions on the moon.”

Colm Gorey was a senior journalist with Silicon Republic