By 
November 6th, 2015
International Space Station.
Credit: NASA
In outer space everyone should hear you wash your hands!
It turns out that the International Space Station (ISS) is a factory for churning out microbes that make for an unhealthy work place.
The results of a new study provide “strong evidence” that specific human skin-associated microorganisms make a substantial contribution to the ISS microbiome – which is not the case in Earth-based cleanrooms.
NASA astronaut Scott Kelly, a flight engineer for Expedition 43 and a member of the one-year crew, is seen here inside the ISS Unity module.
Credit: NASA
Furthermore, the data gathered demonstrate the value of measuring viable cell diversity and population size at any sampling site. This research can be utilized to spot sites on the ISS that can be targeted for more stringent cleaning. Lastly, the new results permit comparisons with other built sites and facilitate future improvements on the ISS that will ensure astronaut health.
Filter and cleaner bag debris
The particulate samples analyzed during this study were gleaned from an ISS HEPA filter, as well as vacuum cleaner bag debris.
The ISS environmental control system includes a distributed ventilation system that contains HEPA filter elements to remove suspended particulate matter from the cabin atmosphere and protect humidity control and air purification equipment from debris accumulation and biofouling.
Flying on a vacuum cleaner. Every Saturday, ISS astronauts vacuum the filters and clean all surfaces.
Credit: ESA/NASA
The new assessment — Microbiomes of the dust particles collected from the International Space Station and Spacecraft Assembly Facilities — explores the environmental microbiome of the ISS as a closed environment.
The work has been published in the scientific journal, Microbiome, led by Aleksandra Checinska of the Jet Propulsion Laboratory’s Biotechnology and Planetary Protection Group in Pasadena, California.
Microbial ecology
Key highlights of the research:
— As long-duration human missions are planned in the future, detection of human pathogens and possible mitigation practices must be developed. In addition, understanding of the ISS microbiome could facilitate the necessary maintenance of this closed habitat and thereby assist in preventing degradation of its components by some microorganisms.
— This study is the first to analyze samples from the ISS air and surface using traditional and state-of-the-art molecular techniques and assays to measure the abundance of microorganisms (i.e., live and dead cells).
— The microbial diversity of the ISS was compared with samples from JPL spacecraft assembly facility cleanrooms, which also represent closed and environmentally controlled built ecosystems.
— The safety and health of spaceflight crewmembers are of the highest importance for current and future missions. Individuals living and/or working in built environments are often susceptible to health issues associated with microorganisms. Moreover, the microbial ecology of ISS remains largely unknown, as study efforts have been mostly focused on microbiological surveillance using cultivation procedures.
Skin shedding
Credit: Checinska et al. Microbiome 2015 3:50 doi:10.1186/s40168-015-0116-3
As noted in the research, it has previously been observed that a high level of visible dust was found in the ISS Node 3 cabin, to the extent it was sticking to the walls. Flight surgeons indicated that this had been reported not just in Node 3 but also throughout the U.S. on-orbit segment and expressed a concern for crew health. Dust on the ISS is expected, with humans being major contributors (via skin shedding, eating, exercising, etc.). Other sources such as on-orbit maintenance activities can release dust from sources such as payloads and systems, clothing, and visiting vehicles.
Part of the new research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. This new work is expected to facilitate future studies to determine how stable the ISS environment is over time.
For an Open Access look at this research, wash your hands and then go to:
Posted in Space News
