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International Journal of Analytical Chemistry:

Trace Analysis in End-Exhaled Air Using Direct Solvent Extraction in Gas Sampling Tubes: Tetrachloroethene in Workers as an Example

Bu makalede, kuru temizleme sektöründe çalışanların nefes örneklerinde Tetrachloroethene kimyasalı arıyorlar. Çok güzel açıklamış.

End-exhaled air is sampled using valveless gas sampling tubes made of glass. Gaseous analytes are transferred to a liquid phase using a microscale solvent extraction performed directly inside the gas sampling tubes. The liquid extracts are analysed using a gas chromatograph equipped, as usual, with a liquid autosampler, and liquid standards are used for calibration. For demonstration purposes, the method’s concept was applied to the determination of tetrachloroethene in end-exhaled air, which is a biomarker for occupational tetrachloroethene exposure.

In the case of tetrachloroethene, the method can be deployed quickly, requires no previous experiences in gas analysis, provides sufficient analytical reliability, and addresses typical end-exhaled air concentrations from exposed workers.

End-Exhaled Air Sampling Procedure. For sampling, the subjects breathed normally and then exhaled completely through the glass tubes (Figure 3) after inhaling and holding their breath for 5 seconds. The subjects then removed the mouthpieces and screwed the sealing caps onto the tubes. Samples collected in the field were transported to the laboratory at ambient temperature and in the dark. The glass tubes were protected using plastic net sleeves to ensure safe handling and transport (Figure 3).