Evaluation of an automatic sampling gas chromatographic–mass spectrometric instrument for continuous monitoring of trace anthropogenic gases

Continuous monitoring of the atmospheric volatile halogenated hydrocarbons is needed in light of the role played by these compounds in global climate change phenomena. The analytical methodology described in the following implies the use of a gas chromatographic–mass spectrometric system equipped with a sampling/pre-concentration unit, for the simultaneous and continuous analysis of a number of halogenated hydrocarbons present in the atmosphere at concentration levels ranging from a few to hundreds of part per trillion by volume. The optimization of the analytical procedure in terms of efficiency, linearity, and reproducibility is reported together with some of the results obtained in the frame of a monitoring activity carried out on a remote mountain station in central Italy.