Karlsson D, Dalene M, Skarping G
Department of Occupational and Environmental Medicine, University Hospital, Lund, Sweden.
Analyst. 1998 Jul;123(7):1507-12. doi: 10.1039/a801918e.
A method is presented for the determination of low molecular weight aliphatic isocyanates, methyl isocyanate (MIC), ethyl isocyanate (EIC), propyl isocyanate (PIC) and butyl isocyanate (BIC), as their dibutylamine (DBA) derivatives. The method is based on sampling in midget impinger flasks containing 10 ml of 0.01 mol l-1 DBA in toluene (as in Parts 1-4 in this series). The samples are analysed using liquid chromatography-electrospray mass spectrometry (LC-ESP-MS) or gas chromatography-mass spectrometry using chemical ionisation with ammonia, monitoring positive ions (GC-PCI). Quantification was effected by monitoring the molecular ions MH+. Aliquots of 10 ml of toluene solutions containing 0.01 mol l-1 DBA were spiked with 0.03-0.85 microgram of MIC-, EIC-, PIC- and BIC-DBA. The correlation coefficients for LC-ESP-MS were in the range 0.9952-0.9999 (n = 14). The repeatability (RSD) was in the range 0.37-1.2% (0.12-0.34 microgram ml-1, n = 10). The instrumental detection limit for MIC was about 15 micrograms l-1, which corresponds to about 0.5 microgram m-3 in a 15 l air sample. The correlation coefficients for GC-PCI were in the range 0.9913-0.9990. The repeatability (RSD) was in the range 1.1-4.9% (0.12-0.34 microgram ml-1, n = 10). The instrumental detection limit for MIC was about 0.2 microgram l-1, which corresponds to about 0.05 microgram m-3 in a 15 l air sample. Using electron ionisation, the instrumental detection limit for MIC was about 10 micrograms l-1. No derivatisation reaction losses were seen when the derivatization reaction between PIC and DBA took place in the presence of morpholine, propylamine, ethanol, phenol and water. When mineral wool with a phenol-formaldehyde-urea resin was thermally degraded, 0.1% m/m of MIC was released. In air samples taken on top of a new electric oven insulated with mineral wool, MIC was found in the range 0.1-3 mg m-3. No MIC in air was found from a pre-heated oven.
本文介绍了一种测定低分子量脂肪族异氰酸酯的方法，即测定异氰酸甲酯（MIC）、异氰酸乙酯（EIC）、异氰酸丙酯（PIC）和异氰酸丁酯（BIC），以它们的二丁胺（DBA）衍生物形式进行测定。该方法基于在装有10 ml 0.01 mol l-1甲苯中二丁胺（如本系列第1 - 4部分所述）的小型冲击式吸收瓶中进行采样。使用液相色谱 - 电喷雾质谱（LC - ESP - MS）或采用氨化学电离并监测正离子的气相色谱 - 质谱（GC - PCI）对样品进行分析。通过监测分子离子MH+进行定量。向10 ml含有0.01 mol l-1二丁胺的甲苯溶液等分试样中加入0.03 - 0.85微克的MIC - DBA、EIC - DBA、PIC - DBA和BIC - DBA。LC - ESP - MS的相关系数在0.9952 - 0.9999范围内（n = 14）。重复性（相对标准偏差，RSD）在0.37 - 1.2%范围内（0.12 - 0.34微克ml-1，n = 10）。MIC的仪器检测限约为15微克l-1，这相当于在15 l空气样品中约0.5微克m-3。GC - PCI的相关系数在0.9913 - 0.9990范围内。重复性（RSD）在1.1 - 4.9%范围内（0.12 - 0.34微克ml-1，n = 10）。MIC的仪器检测限约为0.2微克l-1，这相当于在15 l空气样品中约0.05微克m-3。采用电子电离时，MIC的仪器检测限约为10微克l-1。当PIC与DBA之间的衍生化反应在吗啉、丙胺、乙醇、苯酚和水存在下进行时，未观察到衍生化反应损失。当含有酚醛脲树脂的矿棉热降解时，释放出0.1% m/m的MIC。在以矿棉隔热的新电烤箱顶部采集的空气样品中，发现MIC的含量在0.1 - 3 mg m-3范围内。预热烤箱的空气中未发现MIC。
