環氧乙烷（ethylene oxide, EtO）是醫院及可拋棄式醫療器材製造工廠所廣泛使用之低溫氣體消毒滅菌劑，同時也是化學合成的原料。環氧乙烷除了對人體健康有明顯的危害之外，亦具有極易燃燒和爆炸的危險。針對空氣中環氧乙烷的暴露評估技術，本研究使用固相微萃取設備並應用溴化氫（HBr）與環氧乙烷（EtO）反應生成2-溴乙醇（2-bromoethanol）之原理，進行採樣設備之設計與分析方法之實驗室驗證，同時並與市售3M #3551環氧乙烷被動式採樣器進行平行比對。 本研究所設計之環氧乙烷採樣分析方法具有免溶劑脫附、萃取時間短、組合簡單、攜帶方便並可重複使用等優點；研究方法則首先以Carboxen / Polydimethylsiloxane (CAR/PDMS)萃取纖維經頂空萃取法裹附溴化氫30秒後，組裝成被動式採樣器，然後利用動態標準氣體製造系統於實驗室中模擬暴露狀況並進行相關驗證，獲得採樣器之實驗採樣率為（2.58±0.14）× 10-2 mL/min。此外，研究中也將3M #3551採樣器一併置於暴露腔內中進行平行比對；樣本收集完畢後則以氣相層析質譜儀（GC/MS）進行分析。 研究結果顯示3M #3551環氧乙烷被動式採樣器的脫附效率為103?3.8%；SPME被動式採樣器的脫附效率為100﹪﹔採樣器的壽命試驗顯示經貯存於4℃冰箱中7天後，樣本之採集回收率可達93%；樣本儲存穩定性試驗顯示，置於4℃冰箱中保存7天後，回收率可達97﹪。相對於25℃下的實驗條件，4℃所獲得的實驗採樣率為25℃的74﹪；35℃所獲得的實驗採樣率則為25℃的95﹪；不同相對濕度（10﹪與80﹪）、濃度（0.5～8ppm）及風速（0～50fpm）不會影響SPME被動式採樣器之採樣率；經實驗室與現場平行比對皆顯示3M #3551與SPME被動式採樣器之間有良好之相關 (R=0.9860，0.9704)。; The purpose of this study is to validate a new time-weighted average sampling method for ethylene oxide (EtO) in air based on the technique of solid phase microextraction (SPME) and the use of hydrobromic acid (HBr). The sampler designed in this study showed the advantages of solvent-free, short extraction time and high reproducibility. HBr was first loaded onto the Carboxen/Polydimethylsiloxane (CAR/PDMS) fiber through 30 sec of headspace extraction. The diffusive sampler was then assembled and a dynamic standard gas generation system was used to validate the performance of the sampler. After sampling, the sampler was inserted into the injection port of gas chromatography/mass spectrometry (GC-MS) for thermal desorption and sample analysis. Besides, 3M #3551 monitor which was a commercially available sampler for ethylene oxide, was side-by-side compared with the designed sampler in the lab exposure chamber. The experimental sampling rate of the designed sampler was found to be （2.58±0.14）× 10-2 mL/min; the desorption efficiency of the 3M #3551 monitor used was found to be 103.0?3.8%; the desorption efficiency of the SPME sampling device used was found to be 100%. The shelf life test of the designed SPME sampling device showed the recovery around 93% after 7 days storage at 4℃; the sample stability test showed the recovery around 97% after 7 days storage at 4℃; the side-by-side comparison with 3M #3551 monitor in the laboratory and in the fields both showed good linear relationship (R =0.9860, 0.9704). The experimental sampling constant at 4℃ was (2.27±0.14)×10-2 mL/min (around 74% compared with sampling at 25℃) while it was (2.94±0.12)×10-2 mL/min at 35℃ (around 95% compared to 25℃). Different relative humidities (10% and 80%), concentrations (0.5~8ppm) and wind velocities (0~50 fpm) had no effects on the sampling rate.
