It seems then sample analysis should happen in place instead of bringing samples back to study. I think this motivates the need for better ISS equipment, or off-site research labs, like on the moon.
By that standard, any room you've even been in is "crawling with bacteria." The ISS is cleaned constantly, with a deeper cleaning once per week.
I think any odors would be more related to using dry toilets, stretching clothing in the absence of laundry facilities, and hosting a gym (2 hours exercise per day per crewmember) with no shower. No Rinse Body Bath only goes so far.
