NASA regularly monitors the presence of microbes on the International Space Station (ISS), collecting and analyzing samples from two locations in each US module once every three months, the space agency noted in a public statement.
All cargo that arrives at the station and all vehicles that carry the cargo are subject to meticulous cleaning and monitoring for micro-organisms prior to launch.
Before traveling to the ISS, astronauts are quarantined for ten days. On board the space station, drinking water is treated using the same processes used to treat water on Earth to prevent the growth of harmful microbes.
Micro-organisms, especially bacteria and fungi, are present wherever humans are. Studies of microbes found on the ISS for years have identified them as the same kinds found in human environments on Earth, with very few capable of making people sick.
Since 2013, NASA has been conducting the Study of the Impact of Long-Term Space Travel on the Astronauts’ Microbiome (the study is abbreviated as Microbiome), collecting samples from astronauts’ bodies and from various locations on the ISS to determine the effect of space travel on the immune system and on individuals’ microbiomes, the collection of microbes living both within and on human bodies.
Through a partnership with the Sloan Foundation, NASA is also studying the microbial environment of the space station as a means of learning more about the way micro-organisms colonize, evolve, and adapt in space.
Mark Ott, a microbiologist at the Johnson Space Center, said the Russian Space Agency Roscosmos monitors the microbes on its ISS modules.
Samples collected are cultured on two separate plates containing a growth medium, one for bacteria, and the other for fungi, he reported.
These samples are then returned to Earth, where scientists identify every micro-organism found on them.
On several occasions, a microbe thought to pose a potential health hazard was found via further study to be harmless.
“We should be investigating new and different ways of monitoring spacecraft for micro-organisms. But we must be careful when we interpret the results. NASA has and continues to closely monitor the International Space Station to ensure it provides a safe and healthy environment for our astronauts,” he said.