A recent study suggests that the International Space Station’s extreme cleanliness could be harming astronauts’ health. Researchers found that the ISS is largely devoid of beneficial environmental microbes, which are essential for a healthy immune system. These microbes, typically found in soil and water, can help prevent illnesses like rashes, cold sores, and fungal infections.
To address this issue, scientists recommend introducing more microbial diversity into space stations, similar to what is naturally present on Earth. By fostering diverse microbial communities, astronauts may benefit from improved health without compromising hygiene. The researchers collaborated with astronauts who swabbed 803 surfaces on the ISS, identifying beneficial bacteria and chemicals found in each sample.
The study highlights the importance of a balanced environment for immune system function. Human skin was the main source of microbes throughout the station, with varying levels of presence in different areas. However, free-living environmental microbes were scarce compared to Earth samples from industrialised environments like hospitals.
The researchers warn that introducing beneficial microbes from Earth could be risky if not done properly, and caution is needed to avoid introducing pathogens or fungi into space. Nevertheless, the study underscores the need for more research on creating sustainable and beneficial ecosystems in space to support astronaut health.
Source: https://www.theguardian.com/science/2025/feb/27/international-space-stations-sterile-environment-may-affect-health-of-astronauts-says-study