| 摘要: | 多溴聯苯醚(Polybrominated diphenyl ethers, PBDEs)為廣泛使用的耐燃添加劑，應用於各種民生用品與建築材料。PBDEs具有低反應、低揮發性、高親脂性等性質，而被視為持久性環境污染物，在環境中多存在於底泥、生物檢體等固態樣品中。PBDEs結構相近於甲狀腺T4激素，而視為甲狀腺荷爾蒙干擾物，亦具有神經毒性與致癌可能性。PBDE為可能形成溴化戴奧辛與溴化呋喃的前驅物，因而為歐盟危害物質限用指令(Restriction of Hazardous Substance, RoHS)中明定禁用物之一。 索氏萃取法(Soxhlet extraction)與液固萃取法(Liquid-solid extraction)等傳統萃取法具有損耗大量溶劑、冗長實驗時間及不易自動化等缺點，因此發展加壓溶液萃取法(Pressurized liquid extraction, PLE)對固態環境樣品中PBDEs做有效萃取。在添加PBDEs標準品的無污染高嶺土樣品中，利用改變溶劑組成、溫度、壓力與萃取時間等參數而得最佳化條件，可得最佳回收率為51.9%-103.6%，相對標準偏差值介於1.6%~19.2%之間。 將所發展之最佳化加壓溶液萃取技術應用於不同地區的固態環境樣品，並搭配氣相層析質譜技術作為偵測，建立穩定且堅固的定性定量之分析步驟，檢測多溴聯苯醚的濃度，可得偵測極限範圍為0.1~100 ng/g；定量極限範圍為0.5~200 ng/g。檢測台灣地區七處採樣點的底泥發現，皆有多溴聯苯醚污染，檢出率高達100%；檢出物種包含三溴聯苯醚BDE-028，四溴聯苯醚BDE-047、BDE-085，五溴聯苯醚BDE-099、BDE-100，六溴聯苯醚BDE-138、BDE-153、BDE-154，七溴聯苯醚BDE-183，八溴聯苯醚BDE-203，九溴聯苯醚BDE-206，與十溴聯苯醚BDE-209，各地PBDEs總濃度範圍為7990 pg/g ~37900 pg/g。單口蚓生物檢體亦受多溴聯苯醚污染，檢出物種包含三溴聯苯醚BDE-028，四溴聯苯醚BDE-047，五溴聯苯醚BDE-099、BDE-100，六溴聯苯醚BDE-153、BDE-154，七溴聯苯醚BDE-183，八溴聯苯醚BDE-203，九溴聯苯醚BDE-206，與十溴聯苯醚BDE-209，PBDEs總濃度為434000 pg/g。 建立十溴聯苯醚於液相層析質譜儀(LC/MS)中最佳化層析與質譜游離化條件，以輔助定性與定量十溴聯苯醚於環境底泥樣品與生物檢體中濃度，為本研究另一目標。結果顯示，以甲醇:水溶液(99:1,v/v)作為動相組成溶液，以流速0.6 mL/min沖提並搭配5%異辛烷為摻雜劑進入大氣壓光游離源(APPI)，於毛細管電壓1600V、汽化溫度250℃與乾燥氣體溫度250℃最佳化條件下游離，以MS/MS模式分析，可得偵測極限為50 ng/g；定量極限為150 ng/g。且GC/MS與LC/MS/MS兩種方法用於檢測環境中十溴聯苯醚濃度在95%可信度下無明顯差異。 Polybrominated diphenyl ethers (PBDEs) have multiple applications, either as an additive component or reactive. If use as an additive, PBDEs are not chemically bonded to the polymeric material and therefore may be released or leached from its surface into the environment. PBDEs act as hormone disruptors, neurodevelopmental toxics, and in some cases, carcinogenic agents. In addition, the combustion of these compounds could generate highly toxic polybrominated dibenzo-p- dioxins/furans. A time- and solvent-saving method, pressurized liquid extraction (PLE), to extract PBDEs in sediment was developed in this study. The effects of various operational parameters (i.e., temperature, pressure, etc.) for the quantitative extraction of PBDEs by PLE were investigated. The analytes were then identified and quantitated by GC-MS technique. The PBDEs can be completely extracted by CH2Cl2 : n-hexane (3:2, v/v) at 100?C and 100 atm combined with 15 min static and then 15 min dynamic extraction steps. Recovery of PBDEs in spiked blank kaolin samples ranged from 52 to 104% with 2-19% RSD. Comparison with Soxhlet method, compatible results were obtained by using PLE with much shorter extraction time and a small quantity of solvent consumed. Limits of quantitation (LOQ) were established between 0.5 to 200 ng/g in 10 g of sediment sample. The total contents of PBDEs ranged from 7990 to 37900 pg/g in various river sediments. Deca-BDE (BDE-209) was the major PBDEs detected in sediment samples. Additionally, LC-MS/MS with atmospheric pressure photoionization (APPI) was used for the analysis of deca-BDE as a complementary quantitation method. Various LC and MS parameters were evaluated to optimize the abundance of deca-BDE signal. The nebulizer pressure was optimized as 60 psi; the drying gas flow rate and drying gas temperature were optimized as 10 L/min and 250?C, respectively; and the capillary voltage was optimized at + 1100 V in negative ion mode. Under these conditions, deca-BDE underwent [M?Br+O]? and [M?Br+ O-2Br]? fragmentations. Isooctane was used as an effective dopant for indirect APPI analysis. Comparison with GC-MS method, compatible results were obtained by using LC-APPI-MS/MS with lower LOQ of deca-BDE (done to 150 ng/g in 10 g of sediment sample). |
