Researchers analyzed dust samples from the International Space Station (ISS) and found potential bacterial agents present in the environment. These pathogens, mostly inoffensive on Earth, could lead to infections, inflammations or skin irritations on the astronauts.

Although the ISS orbits 248 miles above our planet, it has more microbes living there than in the cleanrooms at the Jet Propulsion Laboratory here on Earth. Microgravity, space radiation, and carbon dioxide doesn’t seem to scare away these potentially harmful microorganisms, as reported in the study published in the journal Microbiome.

Russian Vacuum Cleaner at the ISS. Scientists need to study the quantity of these organisms in this type of devices, to determine the level of danger they represent for Astronauts. Photo: Russian Federal Space Agency.

“By using both traditional and state-of-the-art molecular analysis techniques we can build a clearer picture of the International Space Station’s microbial community, helping to spot bacterial agents that may damage equipment or threaten astronaut health, and identify areas in need of more stringent cleaning,” said microbiologist Dr. Venkateswaran, leader of the study, according to Phys.

Not the “space dust” we can imagine

NASA, along with other space agencies, have been studying these dust samples of the ISS for 15 years now, collecting them from air vents and surfaces. They took the samples and let them “grow” in laboratories —both in space and on Earth— to observe what types of bacteria could develop on these environments.

Using DNA sequencing technologies, scientists analyzed all ‘bug’ samples found on the ISS —all of them, not only those that can grow inside a lab. The bacteria found there is the Actinobacteria, known on Earth for developing mostly in the soil, playing an important role in decomposition and humus formation.

Samples taken from an air-filter screen, placed there for more than 3 years, gave scientists some clues about which organisms were living on the recycled air circulating on the ISS. On the other hand, the samples that came from a vacuum cleaner, also contained the microorganisms that live on the ISS surfaces.

Better to prevent

The results are not very conclusive, however, scientists said that most of the bacteria found on the ISS may represent a risk to human skin, and others are potentially harmful for people with a weak immune system.

Nevertheless, this kind of study can be confusing, as some of these microbes could hardly develop and live on laboratories. Scientists point out the fact that the study is based on genetic analysis, so they can not give conclusions nor give any answer to the question of how these organisms are harmful to astronauts.

“Astronauts are often in a compromised state in microgravity because their bodies are going through so many changes,” Dr. Venkateswaran said, according to Phys. If some of these bacteria gets into the organism of an astronaut with a delicate immune-system condition, it could lead to a disease —although this doesn’t mean that it necessarily will happen.

Preparing for Mars

Looking forward to future projects involving people on Mars, the NASA needs to learn and understand as much as they can about these organisms and how they could affect the health of the astronauts on a long term, considering the time extension of these missions.

“We are stepping in the right direction, and NASA is aware that these are the things required for tomorrow’s human mission to Mars,” Dr. Venkateswaran concluded, according to the LA Times.

Source: Phys