Source: GeoHealth
During the Apollo missions to the Moon, astronauts encountered an unexpected hazard: lunar dust. It clung to their spacesuits; crept into the lunar landers; and caused irritated throats, coughing fits, and watering eyes. Studies later determined that longer-term exposure to lunar dust has chronic health effects. Now, scientists are concerned about how Martian dust could affect astronauts, too.
Wang et al. documented how Martian dust could harm the health of astronauts spending years on the planet and suggest strategies to mitigate dust exposure. On average, Martian dust is only 3 micrometers in diameter, or about 4% the width of a human hair. This fine dust could irritate astronauts’ lungs, seep into their bloodstreams, and increase the risk of ailments such as lung diseases and cancers.
Martian dust contains compounds such as perchlorates, iron oxides, silica, and gypsum that can be toxic to humans. Perchlorates, for instance, can affect hormonal regulation, and inhaling just a few milligrams of Martian dust would surpass the recommended safe dose on Earth. Inhaling silica, as coal miners on Earth do, increases the risk of lung cancer.
The dust also contains metals such as arsenic, chromium, and beryllium, although they may be in concentrations too small to influence human health. Iron oxides help make the dust magnetic and electrostatic, which means it could cling to space suits the same way lunar dust does. In addition, the high doses of radiation that astronauts receive make them more susceptible to pulmonary fibrosis, which exposure to Martian dust could exacerbate.
Without medical facilities on Mars and with Earth a long journey away, emergency treatment of such conditions would be difficult. So mitigating dust exposure in the first place should be prioritized, the researchers say. A combination of air filters, self-cleaning space suits, and electrostatic repulsion devices could help limit astronauts’ exposure. (GeoHealth, https://doi.org/10.1029/2024GH001213, 2025)
—Rebecca Dzombak, Science Writer