以固相微萃取技術同時檢測水中之人造麝香、三氯沙及二氧陸圜

Abstract

日常生活中廣泛使用之消費性產品(consumer products)及個人保健用品(personal care products)中，常可發現人造麝香(synthetic musks)，三氯沙(Triclosan)及二氧陸圜(1,4-dioxane)。人造麝香常被作為香料使用，藉以產生香味，其可分為兩類: 硝基麝香(nitro musks)及多環類麝香(polycyclic musks)；至於使用量，則以硝基麝香中之酮麝香(Musk ketone)、二甲苯麝香(Musk xylene)、以及多環類麝香中之佳樂麝香(Galaxolide)及吐納麝香(Tonalide)為最大宗。另外，三氯沙則具有抗菌作用而廣泛存在於個人保健用品中；至於二氧陸圜被大量使用在工業上，其為合成非離子型界面活性劑時所產生之副產物，因此化妝品及清潔劑等含非離子型界面活性劑之產品中常可檢測到二氧陸圜。 人造麝香、三氯沙及二氧陸圜等物質可能因為使用，透過沖洗及清潔等行為排放到水體環境中，因而造成近年來水中新興污染物質的問題。為了了解臺灣水體環境中這些有害物質的濃度分佈並進一步評估可能的共同暴露與健康風險，本研究利用固相微萃取 (Solid-Phase Microextraction, SPME) 技術，建立同時檢測水中不同特性之人造麝香，三氯沙及二氧陸圜的分析方法。 本研究將SPME纖維以直接接觸水樣的方式，同時對於含有佳樂麝香、吐納麝香、酮麝香、二甲苯麝香、三氯沙及二氧陸圜等已知六種物質濃度的水樣中進行萃取，並針對不同條件進行測試，包含：纖維種類、萃取溫度、萃取時間、轉速、鹽析濃度及脫附效率等，以選擇最適合之萃取條件。萃取完成後，將纖維置於氣相層析串聯質譜儀(Gas chromatography tandem-mass spectrometry)之注射口予以熱脫附，接著進行後續的定性及定量分析。 研究結果發現，最適合採集此六種物質之纖維為65 μm PDMS-DVB，而在選取最適萃取條件後所建立之檢量線的線性範圍，佳樂麝香和吐納麝香為0.05-1 μg L-1，酮麝香、二甲苯麝香、三氯沙及二氧陸圜為0.5-10 μg L-1，相關係數(correlation coefficients)都大於0.99，具有良好線性。六種物質的方法偵測極限(method detection limits, MDLs)範圍為0.02-0.28 μg L-1，然而此六種物質之物理化學特性不同，因此二氧陸圜無法和人造麝香及三氯沙同時分析。本研究進行分析方法之開發，以此固相微萃取技術，針對臺灣7座淨水廠，共18個水樣，同時檢測水中四種人造麝香、三氯沙及二氧陸圜等新興污染物質，結果顯示酮麝香、二甲苯麝香、三氯沙及二氧陸圜皆未檢測出；除了其中兩個水樣之濃度小於定量下限(limit of quantification, LOQ)外，其餘水樣中皆未檢測出吐納麝香；而佳樂麝香的部份，有一個水樣未檢測出濃度，其餘水樣濃度則皆小於定量下限。本研究建立之分析方法能提供一個快速、簡單又環保的環境檢測方法，分析這些水中危害物質。

Emerging environmental pollutants have caused concerned in recent years. For example, a variety of chemical components such as triclosan, synthetic musks (e.g., galaxolide (HHCB), tonalide (AHTN), musk ketone (MK), and musk xyxlene (MX)), triclosan, and 1,4-dioxane, have been detected in different places. Among the chemicals mentioned above, HHCB, AHTN, MX, and MK are used as fragrance ingredients in personal care products. Triclosan are widely used as antimicrobial compounds and perservatives in shampoo, soaps and so on. As for 1,4-dioxane, it could be produced as a by-product during the formation of nonionic surfactants. Human may expose to these chemicals concurrently. Moreover, these chemicals may be discharged into the water environment after usage. To assess the possible health effects, a solid-phase micriextraction (SPME) method for the analysis of HHCB, AHTN, MX, MK, triclosan and 1,4-dioxane in water simultaneously was developed in this research. HHCB, AHTN, MX, MK, triclosan, and 1,4-dioxane were prepared in mixtures as standard solutions. The samples were first equilibrated for 5 minutes before the SPME procedure. Hence, the extraction was performed at 40℃ for 50 minutes with 300 rpm. The 65μm PDMS/DVB fiber was immersed into the water samples. After adsorption equilibrium has been reached, the SPME fiber was inserted into the injector of the gas chromatography with tandem-mass spectrometry and desorbed at 250℃for 2 min for thermal desorption and further analysis. The results show that no carry-over effect was observed from the thermal desorption of the sample. The linear ranges of HHCB and AHTN were from 0.05 to 1 μg L-1. For MX, MK, triclosan, and 1,4-dioxan, the linear ranges were from 0.5 to 10 μg L-1. In addition, the method detection limits were 0.02 to 0.28 μg L-1. The RSD of most compounds were < 10 % and correlation coefficients were all > 0.99. Good linearity and precision were present. However, the physical and chemical properties of each target compound are not similar. Therefore, it could not analyze 1,4-dioxane with synthetic musks and triclosan in water concurrently. For the determinations of synthetic musks, triclosan and 1,4-dioxane in water, the SPME procedure was applied in this study. The advantages over conventional methods, such as solvent-free and time-saving, were reached. Besides, the sensitivities of the method for different compounds were low enough to determine the concentrations from environmental water samples.