As humanity sets its sights on the ambitious goal of sending astronauts to Mars, a groundbreaking study led by researchers from University College London (UCL) has uncovered a concerning revelation: the kidneys of astronauts may not be able to withstand the rigors of a round-trip journey to the Red Planet.
The study, published in the prestigious journal Nature Communications, is the most comprehensive analysis of kidney health in space travel to date. It paints a sobering picture of the profound impact that space flight can have on this vital organ, with far-reaching implications for the success of long-duration space missions.
The Toll of Space Radiation on Kidney Health
Since the 1970s, researchers have been aware of the various health issues that arise from space travel, including bone loss, heart weakening, vision deterioration, and the development of kidney stones. These problems are largely attributed to the exposure to space radiation, such as solar winds and Galactic Cosmic Radiation (GCR), which the Earth’s magnetic field typically shields us from on our home planet.
While most manned space flights occur in Low Earth Orbit (LEO), where astronauts receive partial protection from Earth’s magnetic field, the 24 individuals who have traveled to the moon experienced unmitigated GCR exposure, albeit for a relatively short duration of 6-12 days.
The UCL-led team, comprising over 40 international researchers, set out to investigate the impact of space flight on the structure and function of the kidneys. Their findings are nothing short of alarming.
Permanent Kidney Damage and Failure
The study’s comprehensive analysis, which included data and samples from over 40 LEO space missions and 11 space simulations, revealed that both human and animal kidneys undergo significant “remodeling” in space. Specific kidney tubules responsible for maintaining calcium and salt balance showed signs of shrinkage in less than a month of being in space.
The researchers suspect that microgravity is the primary driver of these structural changes, but they also acknowledge the need for further investigation to determine if the combination of microgravity and GCR can accelerate or worsen the damage.
The most concerning discovery, however, was the permanent damage and loss of kidney function observed in mice exposed to radiation simulating a 2.5-year Mars mission. This finding raises serious doubts about the ability of astronauts to survive the three-year round-trip journey to the Red Planet.
Implications for Future Space Missions
“If we don’t develop new ways to protect the kidneys, I’d say that while an astronaut could make it to Mars, they might need dialysis on the way back,” warned lead author Keith Siew, an expert in renal medicine at UCL. “We know that the kidneys are late to show signs of radiation damage; by the time this becomes apparent, it’s probably too late to prevent failure, which would be catastrophic for the mission’s chances of success.”
