When the Apollo astronauts returned from the moon, the dust that clung to their spacesuits made their throats sore and their eyes water. Lunar dust is made of sharp, abrasive and nasty particles, but how toxic is it for humans?

The “lunar hay fever,” as NASA astronaut Harrison Schmitt described it during 1972’s Apollo 17 mission, created symptoms in all 12 people who have stepped on the moon. From sneezing to nasal congestion, in some cases it took days for the reactions to fade. Inside the spacecraft, the dust smelled like burnt gunpowder.

Read more at Earth Sky.