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Purpose of the investigation was to develop a technique of irradiation sterilization of batch syringes with concentrated salt solutions (CaCl2 solution and a mixed solution of MgSO4, NaHCO3 and K2SO4). The syringes are used for mineralization of water produced by orbital systems of electrochemical regeneration of air humidity condensate, and deionized or distilled water from other sources. The paper describes composition of resultant potable water and analyzes quality of irradiation sterilization and stability of concentrated salts inside the syringes irradiated on gamma-source RTs-100M.

Analyzed were quantitative and qualitative characteristics, and processes of formation and transformation of microflora in the atmospheric humidity condensate (AHC) and potable water (PW) regenerated from the condensate by the long-operating system (SRV-K) aboard space station Mir. The paper presents data on species composition of microflora of AHC, and PW regenerated by SRV-K in the period from 1989 through to 1999. The following microbial species were identified in AHC: Alcaligenes (14.8%), Bacillus (3.7%), Citrobacter (7.4%), Clostridium (11.1%), Enterobacter (7.4%), Proteus (7.4%), Pseudomonas (18.5%), and Staphylococcus (100%). There were two PW cocks in SRV-K--"hot" and "cold". "Hot" PW microflora included Alcaligenes (15%), Bacillus (5%), Citrobacter (20%), Clostridium (5%), Enterobacter (15%), Proteus (10%), Pseudomonas (15%), and Staphylococcus (75%). "Cold" PW microflora included Aeromonas (14.3%), Alcaligenes (21.4%), Bacillus (7.1%), Citrobacter (7.1%), Clostridium (7.1%), Enterobacter (7.1%), Moraxella (7.1%), Pseudomonas (7.1%), and Staphylococcus (78.5%). Microbial content averaged 8.9 x 10(2) +/- 1.3 (0.01-4) x 10(3) CFU/ml in condensate and 1.5 +/- 0.1 (0-3.0) CFU/ml in regenerated potable water.

The paper presents a technology and a device for super-high sterilization, and results of investigation on the effect of microwave energy on water contaminated by vegetative forms of microorganisms. Temperatures bringing death to microorganisms in water flow were determined. In addition to the thermal effect of microwave energy, a non-thermal "specific" effect of super-high frequencies on various microorganisms (staphylococci, E. coli and Pseudomonas aeruginosa) was also studied.

Microbial contamination is one of the major characteristics of potable water. The authors give data illustrating occurrence of various microbial species in the inlet products of the water regeneration and supply systems aboard spacecraft. Cultural/biochemical techniques of microbial monitoring (TMM) seem to have the best outlook for potable water assessment in space flight. To qualify water, TMM-I (integral indication of micro-organisms), TMM-C (coccal indication), and TMM-BP (indication of blue pus Pseudomonas aeroginosa) will be necessary and sufficient. Described is a TMM-utilizing unit for microbial analysis.