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Liquid Chromatography / Mass Spectrometry / Mass Spectrometry (LC/MS/MS) is a powerful technique for identifying unknown non-volatile organic compounds dissolved in liquids. One type of LC/MS/MS that is gaining popularity is quadrupole-time-of-flight (QqTOF) mass spectrometry. This technique is now in use at the Johnson Space Center for identification of unknown nonvolatile organics in water samples from the space program. An example of the successful identification of an unknown peak in U.S. Lab Condensate is reviewed in detail in this paper. Each step of the procedure is described in the identification of triethylene glycol mono-n-butyl ether (TGBE) as the unknown analyte. The advantages of time-of-flight instrumentation are demonstrated through this example as well as the strategy employed in using time-of-flight data to identify unknowns. The use of the instrument for quantitative analysis is also demonstrated.

Collapsible bladder tanks called Contingency Water Containers (CWCs) have been used to transfer water from the Shuttle to the Mir and the International Space Station (ISS). Because their use as potable water storage on the ISS is planned for years, efforts are underway to improve the containers, including the evaluation of new materials. Combitherm®, a multi-layer plastic film, is a material under evaluation for use as the CWC bag material. It consists of layers of linear low density polyethylene, ethylene-vinyl alcohol copolymer, nylon, and a solvent- free adhesive layer. Long term studies of the quality of water stored in Combitherm bladders indicate a gradual but steady increase in the total organic carbon value. This suggests a leaching or breakdown of an organic component of the Combitherm.