使用矽膠手環被動式採集空氣中的香氛物質

Abstract

香氛物質是個人護理產品中常見的成份。根據之前的研究顯示，暴露於香氛物質可能會對人體健康造成一些負面影響，例如：呼吸道症狀，特別是針對易感族群。香氛物質的主要暴露途徑為皮膚接觸和吸入；然而至目前為止與皮膚暴露相比，吸入暴露所導致的健康效應討論明顯較少，且關於空氣中香氛物質的濃度數據非常有限。 合適且可用於監測個人暴露的被動式採樣器對於上述的困境大有裨益，而矽膠手環是其中的可能選擇之一。之前的研究指出，矽膠手環可以捕捉到空氣中的揮發性有機化合物（volatile organic compounds, VOCs）和半揮發性有機化合物（semi-volatile organic compounds, SVOCs）；然而，由於缺乏採樣率，研究最終只能得出矽膠手環上的化學物質質量，而無法推算出空氣中的濃度。為了克服這個缺點，本研究改良矽膠手環，並透過提供固定的擴散徑長，以使其成為可獲得空氣中污染物濃度的被動式採樣器。 本研究目的為驗證改良手環於各種環境條件下對台灣個人護理產品中6種常見香氛物質之採樣表現，包含：α-蒎烯（α-pinene）、β-蒎烯（β-pinene）、3-蒎烯（3-carene）、d-檸檬烯（d-limonene）、樟腦（camphor）和α-松油醇（α-terpineol）等。 改良後之矽膠手環由四分之一條矽膠手環、一條橡膠錶帶和2 μm厚的鐵氟龍膜所組裝而成；改良手環的採樣表現則於暴露腔內進行驗證。本研究所使用之暴露腔可用於模擬各種環境條件，例如：不同的溫度、相對濕度、風速和風向等。此外，本研究亦進行其他驗證，包括：採樣器的負載能力、競爭作用和樣本保存穩定度等。另外，所有樣本在進行脫附後使用皆使用氣相層析質譜儀（gas chromatography mass spectrometry, GC-MS）上機分析。 在採樣前須預先清洗矽膠手環，以降低分析時之背景干擾。本研究比較不同有機溶劑的清洗效果，結果顯示乙酸乙酯（ethyl acetate, EtAc）的清洗效果最好。採樣結束後，矽膠手環所收集到的化學物質會在6 mL乙酸乙脂中進行脫附，而所有目標物質的平均脫附效率約為67.8%。此外，研究中以α-松油醇-D3（α-terpineol-D3）作為擬似標準品，並於進行脫附前添加於矽膠手環上。結果表示，α-松油醇-D3的脫附效率為67.1%，與其他目標物質沒有顯著差異。 本研究結果顯示，在不同溫度和相對濕度下所有目標物質的採樣率沒有顯著差異。此外，當風速高於0.2 m/s時，採樣表現是穩定的，且風向並不會對採樣表現造成影響。當暴露腔內同時存在高濃度的甲苯時，目標物質沒有與甲苯產生競爭作用。對於樣本穩定度，所有分析物的回收率在4℃下儲存長達28天時皆無顯著差異。經驗證後，改良後之矽膠手環對於α-蒎烯、β-蒎烯、3-蒎烯、d-檸檬烯、樟腦和α-松油醇之平均採樣率分別為6.02 mL/min、6.92 mL/min、8.37 mL/min、9.5 mL/min、6.72 mL/min和2.52 mL/min。 本研究透過實驗確認改良型矽膠手環對於空氣中香氛物質之採樣效能，而所獲結果對於未來評估個人香氛物質之暴露將會有所幫助。

Fragrances are the typical compositions in personal care products (PCPs). Studies have indicated that exposure to fragrances might cause adverse health effects, such as respiratory symptoms, especially for the susceptible population. Both dermal and inhalation routes are possible for exposure to fragrances. However, to the best of our knowledge, the potential health effect of inhalation exposure is less discussed previously than dermal contact. Nevertheless, the information regarding the levels of airborne fragrances is still limited. A suitable personal passive sampler, which can be used for monitoring, will greatly benefit filling the knowledge gaps. For this purpose, the silicone wristband is one of the possible choices. It has been reported elsewhere that silicone wristbands could sample volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs). However, only the total amounts of chemicals on the wristband were obtained instead of airborne concentrations since the sampling rates were unavailable. To overcome the drawbacks, our lab redesigned the silicone wristband. By providing the diffusion path length, chances are the silicone wristband can be used as a passive sampler with known sampling rates of chemicals. This study is to validate modified wristbands’ sampling performance under various environmental conditions for sampling of 6 commonly seen fragrances in Taiwan’s PCPs, including α-pinene, β-pinene, 3-carene, d-limonene, camphor, and α-terpineol. The modified silicone wristband comprised a quarter of silicone wristband, a rubber watch band, and a 2 μm PTFE membrane on the top. The sampler’s performance was validated in the exposure chamber to collect typical fragrances in different environmental conditions such as temperature, humidity, wind velocity, and direction. Other validations, including loading capacity, competitive effects, and sample stability, were also carried out in this study. All samples were desorbed and analyzed with gas chromatography mass spectrometry (GC-MS). As for the preparation of the sampler, the effects of different cleaning solvents were examined, and the results showed that ethyl acetate (EtAc) was the better choice. After sampling, the chemicals captured by silicone wristbands were desorbed in 6 mL EtAc. The desorption efficiencies for all target chemicals were around 67.8%. In addition, α-terpineol-D3 was spiked on the wristband in the desorption procedure as a surrogate standard. The results showed that the desorption efficiency of the surrogate standard was 67.1%. The validation results showed that the sampling rates were not significantly different under various temperatures and relative humidity. Also, the sampling performance was consistent when the wind speed was higher than 0.2 m/s. Besides, wind directions did not affect the sampling performance, either. Furthermore, the silicone wristband had no competitive effect when toluene existed in the exposure chamber simultaneously with a much higher concentration. For sample stability, the recovery of all analytes showed no significant difference when stored for up to 28 days. After validations, the average sampling rates of α-pinene, β-pinene, 3-carene, d-limonene, camphor, and α-terpineol in the modified wristband were 6.02 mL/min, 6.92 mL/min, 8.37 mL/min, 9.5 mL/min, 6.72 mL/min, and 2.52 mL/min, respectively. In conclusion, the modified wristband had already been validated to sample airborne fragrances. It would benefit the assessment of personal exposures in the future.