Microbial characterization of free floating condensate aboard the Mir space station

Three samples of humidity condensate that had accumulated behind panels aboard the Russian space station Mir were collected and returned to earth for analysis. As these floating masses of liquid come into contact with the astronauts and the engineering systems, they have the potential to affect both crew health and systems performance. Using a combination of culturing techniques, a wide variety of organisms were isolated included Escherichia coli, Serratia marcescens, and a presumed Legionella species. In addition, microscopic analysis indicated the presence of protozoa, dust mites, and spirochetes. These findings suggest the need for more comprehensive microbial analysis of the environment through the use of new methodologies to allow a more thorough risk assessment of spacecraft.