便携式气相色谱-质谱仪测定空气中挥发性有机污染物的准确性

便携式气相色谱-质谱仪(便携式GC-MS)能同时对多组分复杂有机物进行定性定量分析,在环境监测尤其是事故现场应急监测中发挥越来越重要的作用。本文比较了便携式GC-MS与EPATO-14A方法分析测定环境空气中低浓度挥发性有机物(VOCs)的性能,并探讨了利用定量环(loop环)模式测定高浓度VOCs的准确度。结果表明,采用内标标准曲线定量,HAPSITE便携式GC-MS测定空气中VOCs的检出限与EPATO-14A方法相当,准确度和精密度略低,但均符合环境监测分析的要求。利用loop环可对大部分10-6级的高浓度VOCs样品进行较为准确的测定,在突发性环境污染事故中可以得到基本准确的结果。

Veracity on determination of volatile organic compounds in the air by portable gas chromatography-mass spectrometry

Portable gas chromatography-mass spectrometry (GC-MS) can simultaneously carry out qualitative and quantitative analysis of multi-component complex organic compounds. Because of its characteristics, portable GC-MS plays an increasingly important role in environmental monitoring, especially in the spot emergent monitoring. In this study, performance of portable GC-MS on determination of low concentration of volatile organic compounds (VOCs) in ambient air was compared with EPA TO-14A method, and the accuracy of high concentrations of VOCs determined by loop ring model was examined. Results indicated that detection limits of VOCs in air HAPSITE portable GC-MS was equivalent to that of EPA TO-14A method, while accuracy and precision is slightly lower, but all accord with the requirements of environmental monitoring and analysis. The loop ring can be used in the emergent pollution accidents for it can accurately analyze samples in high concentration of VOCs in the grade of 10-6.