Center for Environmental Monitoring and Technology, National Central University, Taoyuan 320317, Taiwan.
Department of Chemistry, National Central University, Taoyuan 320317, Taiwan.
Chemosphere. 2022 Oct;304:135304. doi: 10.1016/j.chemosphere.2022.135304. Epub 2022 Jun 10.
This study aimed to develop a technique to chemically characterize odor issues in neighborhoods of designated industrial zones with pronounced emissions of volatile organic compounds (VOCs). Due to the elusive nature of odor plumes, speedy detection with sufficient sensitivity is required to capture the plumes. In this demonstration, proton-transfer-reaction mass spectrometry (PTR-MS) was used as the front-line detection tool in an industrial zone to guide sampling canisters for in-laboratory analysis of 106 VOCs by gas chromatography-mass spectrometry/flame ionization detector (GC-MS/FID). The fast but less accurate PTR-MS coupled with the slow but accurate GC-MS/FID method effectively eliminates the drawbacks of each instrument and fortifies the strength of both when combined. A 10-day PTR-MS field screening period was conducted to determine suitable trigger VOC species with exceedingly high mixing ratios that were likely the culprits of foul odors. Twenty canister samples were then collected, triggered by m/z 43, 61 (ethyl acetate, fragments, EA), m/z 73 (methyl ethyl ketone, MEK), or m/z 88 (morpholine) in all cases. Internal consistency was confirmed by the high correlation of critical species in the PTR-MS and trigger samples. Several long-lived halocarbons were exploited as the intrinsic internal reference for quality assurance. Oxygenated VOCs (OVOCs) accounted for 15%-75% of the total VOC mixing ratios in the triggered samples. However, EA and MEK, the most prominent OVOC species, did not appear to have common sources with morpholine, which presented with PTR-MS peaks incoherent with the other OVOCs. Nevertheless, these distinctive OVOC plumes were consistent with the multiple types of odor reported by the local residents. In contrast with the triggered sampling, random samples in the same industrial zone and roadside samples in a major metropolitan area were collected. The pronounced OVOC content in the triggered samples highlighted the advantage over random grab sampling to address odor issues.
本研究旨在开发一种技术，以化学表征指定工业区具有明显挥发性有机化合物（VOC）排放的居民区的气味问题。由于气味羽流难以捉摸，因此需要快速检测并具有足够的灵敏度来捕获羽流。在本演示中，质子转移反应质谱（PTR-MS）被用作工业区的第一线检测工具，以引导采样罐进行 106 种 VOC 的实验室分析，方法是通过气相色谱-质谱/火焰电离检测器（GC-MS/FID）。快速但准确性较低的 PTR-MS 与缓慢但准确的 GC-MS/FID 方法相结合，有效地消除了每种仪器的缺点，并在结合时增强了两者的优势。进行了为期 10 天的 PTR-MS 现场筛选期，以确定具有极高混合比的合适触发 VOC 物种，这些物种很可能是恶臭气味的罪魁祸首。然后收集了 20 个罐样本，在所有情况下，均由 m/z 43、61（乙酸乙酯，碎片，EA）、m/z 73（甲基乙基酮，MEK）或 m/z 88（吗啉）触发。通过 PTR-MS 和触发样品中关键物种的高相关性来确认内部一致性。几种长寿命卤代烃被用作内在质量保证的内部参考。含氧挥发性有机化合物（OVOC）占触发样品中总 VOC 混合比的 15%-75%。然而，EA 和 MEK，最突出的 OVOC 物种，似乎与吗啉没有共同的来源，吗啉的 PTR-MS 峰与其他 OVOC 不一致。尽管如此，这些独特的 OVOC 羽流与当地居民报告的多种类型的气味一致。与触发采样相比，还在同一工业区收集了随机样本和主要大都市区的路边样本。在触发样本中，OVOC 含量较高，突出了相对于随机抓取采样解决气味问题的优势。
