Radiation on Earth or in Space: What Does It Change?

Abstract

After having been an instrument of the Cold War, space exploration has become a major technological, scientific and societal challenge for a number of countries. With new projects to return to the Moon and go to Mars, radiobiologists have been called upon to better assess the risks linked to exposure to radiation emitted from space (IRS), one of the major hazards for astronauts. To this aim, a major task is to identify the specificities of the different sources of IRS that concern astronauts. By considering the probabilities of the impact of IRS against spacecraft shielding, three conclusions can be drawn: (1) The impacts of heavy ions are rare and their contribution to radiation dose may be low during low Earth orbit; (2) secondary particles, including neutrons emitted at low energy from the spacecraft shielding, may be common in deep space and may preferentially target surface tissues such as the eyes and skin; (3) a “bath of radiation” composed of residual rays and fast neutrons inside the spacecraft may present a concern for deep tissues such as bones and the cardiovascular system. Hence, skin melanoma, cataracts, loss of bone mass, and aging of the cardiovascular system are possible, dependent on the dose, dose-rate, and individual factors. This suggests that both radiosusceptibility and radiodegeneration may be concerns related to space exploration. In addition, in the particular case of extreme solar events, radiosensitivity reactions—such as those observed in acute radiation syndrome—may occur and affect blood composition, gastrointestinal and neurologic systems. This review summarizes the specificities of space radiobiology and opens the debate as regards refinements of current radiation protection concepts that will be useful for the better estimation of risks.

Joint Cartilage in Long-Duration Spaceflight

“…Only during the Apollo missions, conducted by the United States of America in the late 1960s and early 1970s have humans left the LEO. In the LEO, the Earth’s magnetic field shields away most of the radiation coming from space, especially radiation types with higher energies [ 81 ]. Thus, radiation effects on the joint cartilage of spaceflight participants can be expected to be more pronounced on deep-space missions beyond the LEO, such as to the Moon and Mars, compared with findings obtained in crew staying on space stations that orbit Earth.…”

Microgravity × Radiation: A Space Mechanobiology Approach Toward Cardiovascular Function and Disease

“…Another source of radiation is the interaction of solar and CGR with shielding, creating high Linear Energy Transfer (LET) but low energy metallic particles and protons. The inside of the vessel is also subjected to a higher constant low dose of gamma radiation, about twice the highest natural radiation background found on Earth (Restier-Verlet et al, 2021).…”

“…The radiation doses received for space explorers depend on the time and distance from earth. Estimated doses are 150 mSv/year for space flight in the ISS, 300-400 mSv for traveling to the Moon, and 300-400 mSv/year and 1600-2300 mSv for 2 years traveling to Mars (Shavers et al, 2004;Chancellor et al, 2018;Restier-Verlet et al, 2021) in higher doses of radiation (>100 mGy) it has been clinically shown to lead to cardiac dysfunction over time, where cases have been reported following radiotherapy. Short and longterm effects of radiation induced cardiovascular diseases were observed following radiotherapy treatment of cancers adjacent to heart including lungs, breasts, and esophagus.…”

La radiobiologie française : historique, constats et enjeux

“…De plus, le lien entre radiosensibilité et certaines mutations génétiques reste encore méconnu (Foray et al, 2016). dans le cadre de l'exploration spatiale : l'exploration spatiale requiert une meilleure connaissance des effets biologiques des radiations cosmiques : ce domaine inclut les effets spécifiques aux particules lourdes, aux faibles doses et aux faibles débits de doses (Restier-Verlet et al, 2021). en environnement : avec l'identification des effets spécifiques imputables aux radionucléides dispersés dans l'environnement, la radiobiologie devient également environnementale avec des interactions nombreuses avec les géologues, les botanistes, les experts des différents écosystèmes biologiques.…”