As NASA prepares for a return to the Moon through the Artemis program, one of the biggest health concerns for astronauts has been lunar dust.
The fine, abrasive particles known as the regolith that coat the Moon’s surface have long worried scientists, especially after Apollo astronauts experienced respiratory problems after their missions.
However, groundbreaking research from the University of Technology Sydney has delivered surprisingly reassuring news: lunar dust is less harmful to human lung cells than previously feared, and significantly less toxic than common Earth based air pollution.
The study, led by PhD candidate Michaela B. Smith, represents the most comprehensive analysis yet of how lunar dust affects human health.
Smith investigated the impact of lunar dust simulants on human lung cells in the lab. She then compared the effects to those of airborne particulate matter collected from a busy street in Sydney.
The results were striking. While lunar dust can act as a physical irritant, it did not cause the severe cellular damage or inflammation seen from the urban Earth dust. Smith emphasises this crucial distinction “..between a physical irritant and a highly toxic substance”.
The research focused on the tiniest particles, those measuring 2.5 micrometers or smaller which are small enough to bypass the body’s natural defences and penetrate deep into the lungs.
Using two different types of lung cells representing both upper and lower respiratory regions, the team discovered that Earth dust induced a greater inflammatory response and was more toxic to the cells than the lunar dust simulants.
This finding addresses concerns that arose from the Apollo missions, where astronauts experienced respiratory issues after fine dust that had clung to their spacesuits became airborne in the confined cabin and was subsequently inhaled, leading to respiratory issues, sneezing, and eye irritation.
The key difference lies in how the dust affects cells. The study suggests the primary mechanism of toxicity from lunar dust is mechanical damage caused by the particles’ irregular shape and rough edges.
Crucially, the lunar simulants did not cause significant damage through a process known as oxidative stress (damage caused by unstable molecules), a process often associated with fine particle toxicity.
“Any dust, if you inhale it, you’ll sneeze, cough, and have some physical irritation. But it’s not highly toxic like silica, where you end up with silicosis from being on a construction site for 10 years” – Michaela B. Smith, lead author.
Despite these encouraging findings, NASA continues taking dust exposure seriously. The space agency has developed innovative engineering solutions, including ingenious suits that are attached to the outside of the rover, where the astronaut will climb in and out from inside, and the suit never goes inside, which prevents the dusty suit from ever contaminating the internal cabin environment.
This research provides crucial data for planning long term lunar missions and establishing permanent bases on the Moon, helping to ensure astronaut safety while reducing one significant health concern for humanity’s next giant leap.
Written by Mark Thompson/Universe Today.
