Evaluating the biological impact of shelters on astronaut health during different solar particle events: a Geant4-DNA simulation study.

Mechanistic Monte Carlo simulations have proven invaluable in tackling complex challenges in radiobiology, for example for protecting astronauts from solar particle events (SPEs) during deep space missions which remains an underexplored area. In this study, the Geant4-DNA Monte Carlo code was used to assess the DNA damage caused by SPEs and evaluate the protective effectiveness of a multilayer shelter. By examining the February 1956 and October 1989 SPEs-two extreme cases-the results showed that the proposed shelter reduced DNA damage by up to 57.9% for the October 1989 SPE and 36.7% for the February 1956 SPE. Cell repair and survival modeling further revealed enhanced cell survival with the shelter, reducing lethal DNA damage by up to 64.3% and 88.2% for February 1956 and October 1989 SPEs, respectively. The results presented here highlight the crucial importance of developing effective radiation shielding to protect astronauts during solar storms and emphasizes the need to improve predictions of solar particle events to optimize shelter design.