IRA FLATOW: This is Science Friday, I’m Ira Flatow. Ever since November of 2000, the International Space Station has been permanently occupied making over 17 years of Humanity coming and going. The ISS residents are not alone in orbit, however.

All the astronauts who have visited the space station have brought their microbiomes along for the ride. And this week, researchers report on what they call the microbiology of a singular built environment, also known as the International Space Station. They enlisted an astronaut to take swabs of different parts of the station and then bring them back to Earth for genetic analysis.

To tell us what they found is the lead author of a report in the journal PeerJ, Jenna Lang– did the work while a post-doctoral researcher at UC Davis in the lab of Jonathan Eisen. And now she’s a Senior Scientist at BioConsortia, a biotech startup company. Welcome to Science Friday.

JENNA LANG: Hi, Ira, I’m so excited to be here.

IRA FLATOW: We’re excited to have you. How is your day going?

JENNA LANG: It’s been full of nerves and excitement getting ready for this.

IRA FLATOW: Don’t worry about it. There’s no one listening to us. Don’t be nervous.

JENNA LANG: OK, OK, just you and me.

IRA FLATOW: There have been stories about your work saying, oh this space station is super germy. Are those accurate?

JENNA LANG: They’re accurate if you consider that some people call bacteria germs and that there are bacteria on the space station as there are everywhere we’ve ever looked. So germy in terms of icky, no, I don’t think the space station is icky. The space station looks a lot like our homes on earth.

IRA FLATOW: If your home is icky, then you’d think the space station is icky.

JENNA LANG: Yeah, maybe your home is icky. But I don’t think theirs is.

IRA FLATOW: Well I’ll plead guilty to that. Let’s talk about the swabbing that went on. What kinds of microbes did you find after you swapped around there?

JENNA LANG: Most of the microbes that we found are microbes that are associated with humans. A lot of them are associated with human skin, the human oral cavity, human upper airway. So exactly as you would expect, the ISS is a relatively closed environment, And when they open the doors, it’s mostly humans that come in, and they bring their microbes along with them.

IRA FLATOW: Give me an idea of how the swabbing works. What parts of the station do you go around to?

JENNA LANG: So this project is a part of Project Mercury, which was a project that involved citizen scientists swabbing their cell phones and shoes and professional cheerleaders swabbing sporting venues. And what we wanted to do was to collect swabs that would be comparable to cell phones and shoes as well as samples that would be comparable to the homes that people live in here on Earth. The work was funded by the Microbiology of the Built Environment program at the Sloan Foundation. So they’re interested in what kind of microbes live in built environments. And we view this as an extreme built environment.

IRA FLATOW: So you went around swabbing the space station. Were there are places that you could not get to that you wanted to?

JENNA LANG: Well we did not have access to the kitchen, which is in the Russian module. And we did not have access to the toilet, which we had sort of conflicting feelings about sampling. But we were trying to mirror the sampling sites at Rob Dunn’s group’s, Wildlife of Our Homes project, where they did sample toilet seats. So we were hoping to be able to do that as well. And we were not able to sample the toilet seats.

IRA FLATOW: These were sort of the most microbial rich targets that you couldn’t get to. The kitchen where we know the counters in the kitchen are the dirtiest places in the house. And not to mention the other place.

JENNA LANG: Right, but what was really interesting to me is some of the places that we were able to sample, I had this fear that maybe when I compared these ISS surfaces to samples of the human microbiome, that they might resemble, for example, the human gastrointestinal tract. And then I would have to be the person reporting to the world that we know that ISS looks like a human gut. And I was very pleased not to be able to do that. We were able to sample a lot of surfaces across the space station, and they had the diversity that you would expect to find in a typical human home.

IRA FLATOW: Was that a surprise you?

JENNA LANG: That was a surprise. And we didn’t have a lot of firm expectations about what to find. But I did think that the diversity would be lower because you can’t open the window to air out the ISS. So I thought that the diversity would be lower and that perhaps we would find a greater abundance of human pathogens. But what we found and we were able to compare our work to Steve Campbell’s work in hospitals is that it’s comparable to a hospital room that’s mechanically ventilated versus a hospital room that has a window open.

IRA FLATOW: So things are pretty much similar. Were there are differences in the microbes in different parts of the space station or are they more or less spread around?

JENNA LANG: With the sample size that we were able to obtain, we couldn’t distinguish any sort of biogeography on the space station. They were sort of all over the place.

IRA FLATOW: I like that word. We’ve got a new word for us today, biogeography. I don’t think anybody has ever said that.

JENNA LANG: There are more exhaustive studies underway. A Japanese group just finished one and NASA has been collecting samples for decades that are just waiting for analysis.

IRA FLATOW: Well Dr. Lang, thank you for enlightening us about the microbiome. You know it’s one of our favorite subjects up there in the space station.

JENNA LANG: Yes, mine too.

IRA FLATOW: And you were a great guest. Don’t be so nervous. You were terrific.

JENNA LANG: OK, Thank you.

IRA FLATOW: Jenna Lang, a Senior Scientist at BioConsortia, was talking about the microbiome in the space station.

Copyright © 2017 Science Friday Initiative. All rights reserved. Science Friday transcripts are produced on a tight deadline by 3Play Media. Fidelity to the original aired/published audio or video file might vary, and text might be updated or amended in the future. For the authoritative record of Science Friday’s programming, please visit the original aired/published recording. For terms of use and more information, visit our policies pages at http://www.sciencefriday.com/about/policies/