MOSCOW, June 6. /TASS/. The microbiota at the International Space Station (ISS) has worsened with microorganisms surpassing normal levels detected in more than half of samples, Director of the Institute of Biomedical Problems of the Russian Academy of Sciences (RAS) Oleg Orlov said.

"The analysis of the results of a microbiological monitoring of the living environment of the ISS’ Russian segment indicates that the condition of the ISS’ living environment has gotten worse beginning with the 55th expedition. Cumulative results show that microorganisms in numbers exceeding normative requirements were detected in 65% of samples," the institute cited him as saying at a joint meeting of the Russian Academy of Sciences’ Space Council and the Presidium of the Scientific and Technical Council of Roscosmos.

According to the scientist, the emergence of microorganisms at the space station is inevitable since they are being brought in by cargoes and cosmonauts. As a result, they adopt to the new environment. He noted that the process of biological pollution is counteracted by preventive and control measures yet the contamination is gradually growing.

He pointed out that these microorganisms include those belonging to the third and fourth pathogenicity groups such as staphylococci, streptococci, and bacteria which may cause allergies or diseases of soft tissues and the upper respiratory tract, while fungal species which were also detected at the station may cause allergies and mycoses.

The detected microorganisms represent a threat both to humans and equipment. "The isolated fungal species are capable of damage to materials and equipment," the scientist explained.