Toxic Mars Dust Adds Another Health Risk to Astronauts' List

Astronauts already deal with a host of health risks each time they visit space, but if they ever make it to Mars, they'll have to reckon with yet another. New research has found that the planet's famous rust-colored dust doesn't just consist of hazardously small particles—it also contains compounds that could cause or exacerbate pulmonary disease, thyroid dysfunction, lung disease, gastrointestinal irritation, cancer, and a host of other health problems. Experts say this new risk won't stop humans from eventually stepping foot on the Red Planet, but it will certainly make future missions more of a challenge.

The research, published last month in the journal GeoHealth, focuses on 10 components of Mars dust and the hazards they're known to pose here on Earth. One of those components is actually the dust's size: With grains averaging 3 microns (roughly the size of a single ...