Extraterrestrial regolith is hemostatic and potentially suitable for hemorrhage control in space.

Abstract

<h4>Background</h4>Long-duration space missions beyond low Earth orbit pose increased risks of injury to astronauts. Traumatic hemorrhage will be a cause of preventable death. Due to payload constraints, <i>in situ</i> production of medical materials is essential. Regolith from the Moon, Mars, and asteroids is rich in silicates, which may serve as a hemostatic agent.<h4>Objectives</h4>Here, we aimed to evaluate whether extraterrestrial regolith simulants, their mineral components, and meteorites can activate coagulation through factor (F)XII and control bleeding.<h4>Methods</h4>The procoagulant potential of Lunar and Martian regolith simulants, their component silicate minerals, and meteorite samples was assessed <i>in vitro</i>. Plasma clotting turbidity, thrombin generation, and FXIIa chromogenic assays were performed using either normal or FXII-inhibited/immunodepleted human plasma. ζ Potential and SiO₂ content were also plotted against time to fibrin clot formation. The <i>in vivo</i> efficacy of Lunar highland simulant (CSM-LHT-1), Mars global simulant high clay (CSM-MGS-1C), and Northwest Africa-869 chondritic meteorite was assessed in a pilot study using a porcine model of penetrating hemorrhage.<h4>Results</h4>All extraterrestrial regolith simulant samples accelerated clotting, thrombin generation, and FXII activation in normal plasma, with reduced effects in FXII-immunodepleted or FXII-inhibited plasma. Phyllosilicates showed greater procoagulant activity than framework silicates. <i>In vivo</i>, wounds treated with regolith remained clotted longer and lost less blood than wounds treated with gauze alone, with the Northwest Africa-869 chondrite meteorite significantly improving clotting and reducing blood loss.<h4>Conclusion</h4>Extraterrestrial regolith activated coagulation in a FXII-dependent manner and reduced blood loss in a trauma model of penetrating hemorrhage. This suggests that extraterrestrial regolith may be used as a hemostatic agent during space missions.