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The concentration of helium in groundwater may be a good environmental tracer for groundwater dating in hydrogeology. In this work, we present a chromatographic method for simultaneous analysis of helium, neon, and argon in groundwater from a single groundwater sample. Proper use of environmental tracers for dating purposes requires the knowledge of the recharge temperature of the system and the excess air. Both parameters can be determined by measuring the concentration of argon and neon in groundwater. The lowest helium concentration in groundwater is 4.8 × 10-8 cm3STP/gH2O at sea level and temperature 10 °C. In view of the deficiency of a suitable detector with a limit of detection for helium at the level of 4.8×10-8 cm3STP/gH2O, the application of the enrichment method is necessary. In this work, the cryogenic method of enrichment with activated charcoal at abated pressure conditions was applied. Helium, neon and argon are analyzed on two gas chromatographs equipped with capillary and packed columns (filled with molecular sieve 5A and activated charcoal) and three thermo-conductive detectors. The chromatographic method was applied to groundwater dating from Kraków and Zarnowiec aquifers. The levels of detection for measurement systems for the tested compounds are. 1.9 × 10-8 cm3STP/cm3 for neon, 3.1 × 10-6 cm3STP/cm3 for argon, and 1.2 × 10-8 cm3STP/cm3 for helium. [ABSTRACT FROM AUTHOR]

The results of the measurements of the concentrations of freons (F-11 and F-113), chloroform (CHCl3), trichloroethane (CH3CCl3) and carbon tetrachloride (CCl4) in air are presented. The data concern concentration measurements that have been conducted in Krakow since half way through 1997 to the end of 1999. The mean monthly values of these concentrations have been compared with the data from Mace Head, the station situated at a similar longitude as Krakow. It has been concluded that, in the observed period of time, the concentrations of the pollutants in Krakow are higher than in Mace Head. The mean monthly concentrations of F-11 and CCl4 decrease in Krakow faster than in Mace Head (2.5 and 3.3 times, respectively). The concentrations of CHCl3 and CH3CCl3 decrease at both locations, but the change is greater in Krakow. In Krakow, the observed increase of F-113 is 0.13 ppt/month and has an opposite trend than in the same period at Mace Head. [Copyright &y& Elsevier]

Chromatographic studies on breath composition are aimed at finding volatile markers useful for medical diagnostics or in screening investigations. Studies leading to the development of screening breath tests are especially important for the diagnostics of chronic kidney disease (CKD) and type 2 diabetes mellitus (T2DM). The aim of the presented study was to confirm diagnostic usefulness of chosen volatile compounds detected in breath, which are suggested as potential biomarkers of renal dysfunction and diabetes. Breath analysis were carried out in three groups: 10 healthy volunteers, 10 patients with CKD and 10 patients with CKD and T2DM. All exhaled air samples were analyzed using gas chromatograph (Agilent 6890GC) coupled with mass spectrometer (5975MSD). Thermal desorption was applied as the enrichment method. TMA was detected only in CKD patients. Higher breath concentrations of methanethiol (MeSH) were observed in CKD patients with coexisting diabetes than in patients with renal dysfunction only or in the healthy group. There was a tendency of increasing MeSH concentration in breath with increasing total glutathione in plasma (r = 0.53, p = 0.0026). Also, a trend of increasing dimethylsulfide (DMS) levels detected in breath was noticed with an increase of hydrogen sulfide concentration in plasma (r = 0.74; p = 0.00001) as well as with aspartate aminotransferase (AST), (r = 0.61; p = 0.001). The presented results suggest the possibility of applying TMA, MeSH, and DMS detection in breath as diagnostic methods [ABSTRACT FROM AUTHOR]

Aim: The studies on volatile organic compounds emitted from skin are an interest for chemists, biologists and physicians due to their role in development of different scientific areas, including medical diagnostics, forensic medicine and the perfume design. This paper presents a proposal of two sampling methods applied to skin odor collection: the first one uses a bag of cellulose film, the second one, using cellulose sachets filled with active carbon., Materials & Methods: Volatile organic compounds were adsorbed on carbon sorbent, removed via thermal desorption and analyzed using gas chromatograph with mass spectrometer., Results: The first sampling method allowed identification of more compounds (52) comparing to the second one (30). Quantitative analyses for acetone, butanal, pentanal and hexanal were done., Conclusion: The skin odor sampling method using a bag of cellulose film, allowed the identification of many more compounds when compared with the method using a sachet filled with active carbon.