Ochiai Nobuo, Daishima Shigeki, Cardin Daniel B
Nishikawa Keisoku Co. Ltd., 2-11-13 Nakacho, Musashino-shi, Tokyo 180-0006, Japan.
J Environ Monit. 2003 Dec;5(6):997-1003. doi: 10.1039/b307777m.
A canister-based 1 week sampling method using a mechanical flow controller and a 6 L fused-silica-lined canister was evaluated for the long-term measurement of 47 VOCs in ambient air at pptv (volume/volume) to ppbv levels by use of a three-stage preconcentation method followed by GC-MS analysis. The GC conditions were initially optimized for complete separations of several pptv-level VOCs (e.g. vinyl chloride, 1,3-butadiene, acrylonitrile, 1,2-dichloroethane and chloroform) in ambient air because the selected ions are easily interfered with by coexisting C4-, C5-hydrocarbons and analytes presented at ppbv levels. Thirty-four VOCs determined by the 1 week and 24 h sampling method in December 16-22 (2002) had concentrations of 6.0-15000 pptv per compound. Concentrations of 28 VOCs (including polar VOCs (e.g. methyl isobutyl ketone and butyl acetate)) obtained by the method were approximately equal to the mean values calculated from 24 h sampling (< +/- 10% deviation). Six VOCs that had low concentrations of 6.0-43 pptv showed more than +/- 10% deviation. Thirteen VOCs were not detected during the entire sampling period. The effect of relative humidity or ozone for the specific VOCs (e.g. MIBK, butyl acetate, vinyl chloride, 1,3-butadiene and styrene) was negligible.
评估了一种基于罐的1周采样方法，该方法使用机械流量控制器和一个6 L内衬熔融石英的罐，通过三级预浓缩方法然后进行GC-MS分析，用于长期测量环境空气中47种挥发性有机化合物（VOCs），浓度范围为万亿分之一体积比（pptv，体积/体积）至十亿分之一体积比（ppbv）。由于所选离子容易受到共存的C4-、C5-碳氢化合物和ppbv水平的分析物的干扰，因此最初对GC条件进行了优化，以实现环境空气中几种pptv水平的VOCs（例如氯乙烯、1,3-丁二烯、丙烯腈、1,2-二氯乙烷和氯仿）的完全分离。2002年12月16日至22日通过1周和24小时采样方法测定的34种VOCs，每种化合物的浓度为6.0 - 15000 pptv。通过该方法获得的28种VOCs（包括极性VOCs（例如甲基异丁基酮和乙酸丁酯））的浓度大约等于从24小时采样计算出的平均值（偏差< +/- 10%）。6种浓度较低（6.0 - 43 pptv）的VOCs显示出超过+/- 10%的偏差。在整个采样期间未检测到13种VOCs。相对湿度或臭氧对特定VOCs（例如甲基异丁基酮、乙酸丁酯、氯乙烯、1,3-丁二烯和苯乙烯）的影响可忽略不计。
