On-site determination of nerve and mustard gases using a field-portable gas chromatograph-mass spectrometer

摘要

A field-portable gas chromatograph-mass spectrometer (the Hapsite system) was evaluated for onsite determination of nerve gases and blistering agents. The analytical sequence involved gas sampling for 1 min, microtrap concentration (1 min), apolar capillary gas chromatographic separation (10 min), electron ionization, quadrupole mass spectrometric data acquisition, and personal computer-based data analysis. Vapor containing 1mg/m3 sarin (GB), 1mg/m3 soman (GD), 3mg/m3 tabun (GA), and 0.5mg/m3 mustard gas (HD) was analyzed using the Hapsite system. The chemical warfare agents (CWAs) were detected within 10 min, and identified from their respective mass spectra according to the built-in NIST library database. Being based on the signal levels of the CWA peaks observed in mass chromatograms for m/z 99 (GB), 126 (GD), 70 (GA), and 109 (HD), the detection limits (S/N = 3) were estimated to be 0.2, 0.5, 8, and 0.3μg/m3, respectively. A carryover phenomenon was observed after injecting actual CWA samples, necessitating several blank-air purges of the system. The extent of adsorption was in the order: HD > GA > GD > GB.