Production of hydrogen peroxide in Martian and lunar soils

Freshly ground basaltic minerals produce sufficient quantities of hydrogen peroxide (H₂O₂) when immersed in solution to explain the oxidizing characteristics of Martian soil samples collected by the Viking landers. H₂O₂ production occurs as a result of reactions between water and defects at the surface of mechanically pulverized minerals, analogous to carcinogenic quartz dusts. Our results also indicate that dehydroxylation of mineral surfaces results in increased H₂O₂ production, a highly relevant finding for dusts on the airless surface of the Moon. Reactive, pulverized minerals are important on planetary bodies where impact processes have generated fine-grained basaltic dusts, and may pose a significant health risk to astronauts visiting planetary surfaces where impacts have generated such materials.