呼出氣體中四氯乙烯之檢測

Determination of Tetrachloroethylene in Exhaled Breath

四氯乙烯 （tetrachloroethylene） 是一種常用的乾洗及去油汙工業溶劑。高劑量暴露可引發包括中樞神經症狀、肝、腎臟病變及不孕與自發性流產，甚至癌症，等危害。因此除了作業環境監測外，應用生物偵測指標方法以評估勞工先前暴露量，當可增強勞工保護工作。而呼出氣體檢測屬於非侵入型之生物偵測方法，因此較易獲得勞工的配合。本研究運用吸附劑吸附及熱脫附技術，配合GC/FID 來檢測作業勞工呼出氣體中的四氯乙烯。結果顯示，如以採樣體積0.5 升計算，檢量線的線性範圍涵蓋0.1-20 ppm；樣品的平均熱脫附效率為100.7%；同日及異日的分析精密度分別為4.1 及3.4%；方法偵測極限為每隻採樣管0.49μg。另外，樣品在室溫下儲存便可維持三周的穩定性。呼吸採樣器對於高濕度的四氯乙烯氣體，也顯示出良好的採集效率。總合而言，本檢測分析方法，除具有專一性外，並有良好的準確及精密度，可作為評估勞工四氯乙烯暴露的生物偵測參考分析方法。

Tetrachloroethylene (PERC) is a commonly-used garment dry-cleaning and metal degreasing solvent. Exposures to high level of PERC causes various neurological, hepatic, and renal effects, as well as higher infertility and spontaneous abortion rate, and even cancer. Therefore, biological monitoring of exposure provides an additional protection of workers’ health, in addition to conventionally environmental monitoring. The current study aimed to establish the analytical methods to determine the PERC levels in exhaled breath. PERC in exhaled (alveolar) breath was analyzed using thermal desorption and GC/FID. The breath sampling device is adopted from literature with modification. The quantitative standard curve ranges from 1 to 20 ppm (0.1-2 times the ACGIH’s BEI value), for a sampling volume of 0.5 liter. The average desorption efficient is 100.7% while the intra-day and inter-day precisions are 4.1 and 3.4%, respectively. The method detection limit is 0.49μg per sampling tube. Samples are stable at room temperature for at least 21 days. The proposed analytical method is specific, and demonstrated to have sufficient accuracy and precision, thereby, can be used as a biological method to determine workers’ exposure to tetrachloroethylene.