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年度	103	專案性質	實驗性質
專案類別	研究專案	研究主題	調查
申請機構	國立高雄師範大學	申請系所	生物科技系(所)
專案主持人	陳士賢	職等/職稱	教授
專案中文名稱	汽油污染場址之化學指紋鑑定研究
中文關鍵字	化學指紋鑑定；汽油污染場址；污染源辨識
專案英文名稱	Chemical Fingerprinting of Gasoline Contaminated Sites
英文關鍵字	Chemical fingerprinting；Gasoline contaminated sites；Source identification
執行金額
執行期間	2013/11/25 至 2014/11/24
計畫中文摘要	隨著科技的進步與發展，環境鑑識技術所使用之分析技術與儀器設備也日趨 成熟，但國內除環境檢驗所與中油探採研究所外，對於應用環境法醫技術於石化 產品造成之土壤與地下水污染之案例及判識經驗相對有限，對於建制石化產品造 成之地下環境污染鑑識工作所需之基本資料庫及相關作業規範屬於發展階段，為 判定污染源，需掌握國內油品之基本物理及化學資訊，而此基線資訊之獲得無法 單純仰賴石化業者主動提供，必須仰賴學術單位之積極建立。 本研究計畫團隊結合學術研究單位及長期進行土壤及地下水分析的國內最大 環境檢驗公司，針對國內土壤及地下水污染常見之汽油油品污染，建立汽油污染 場址相關的環境鑑識分析技術。本計畫目的為持續發展環境法醫技術，應用於國 內常見之汽油污染場址的污染源判釋，評估汽油污染場址之相關環境法醫鑑識分 析技術，並探討風化過程對油品化學指紋特性及鑑識之影響，以利國內石化污染 場址污染物來源的研判及追蹤。各分項目的如下所述: (1) 建立及整合汽油組成、物理及化學特性、層析圖譜基本資料。 (2) 建立汽油油品污染鑑識指標化合物及參數。 (3) 評析汽油油品污染場址的可行性環境鑑識流程。 (4) 分析風化過程對汽油化學指紋特性及鑑識之影響。 (5) 評估汽油及柴油污染場址指紋及資料鑑識分析技術之適切性。 在建立汽油油品基本資料庫工作上，除了彙整過去油品相關資料外，並進行 汽油(中油及台亞)及汽油混和柴油基本特性分析，並且建立油品污染鑑識指標化 合物及參數。本研究將風化條件分為三種系統，一為實驗室製備的汽油及汽油混 和柴油污染土壤放置室溫(25°C)下避光且密閉之環境，二為實驗室製備的汽油及 汽油混和柴油污染土壤放置室溫(25°C)下避光且開放之環境，三為實驗室製備的 汽油及汽油混和柴油污染土壤放置室外，平均溫度為 24°C 且自然光照之環境， 同時以不同有機碳含量之污染土壤進行室外實驗，觀察風化作用對 methyl tert butl ether (MTBE)、benzene、toluene、ethylbenzene、xylenes、n-propylbenzene、1,2,3- trimethylbenzene 、 1,2,4-trimethylbenzene 、 1,3,5-trimethylbenzene 、 1,3- diethylbenzene、1,2,4,5-tetramethylbenzene 及 1,2,3,5 -tetramethylbenzene 等 14 項汽油指標化合物之影響，並配合總石油碳氫化合物濃度(total petroleum hydrocarbon, TPH)、碳優指數(carbon preference index, CPI)、風化指標(weathering index, WI)、 苯加甲苯對應乙苯加二甲苯比例(benzene+toluene/ethylbenzene+xylenes, B+T/E+X) 以及 methylnaphthalene ratio (MNR)等比值進行探討。 結果顯示，當風化時間越長，汽油污染土壤其特徵參數 TPH 濃度有逐漸減 少的趨勢，以中油 98 汽油污染土壤為例，其 TPH 濃度由 5229 mg/Kg 降為 319 mg/Kg，原因是 n-alkanes 較易受風化作用影響，而風化指標(WI)隨著時間也有遞 減的趨勢，由 3.97 降為 0.57，表示汽油中低碳數化合物因自然風化作用而有減少 的現象。 針對評估風化過程對汽油化學指紋及鑑識之影響，風化鑑識技術應用於國內 污染場址樣品之洩漏來源鑑別，本計畫結果顯示國內兩間油品供應商汽油中所含 化合物比例皆不相同，其中烷基化 naphthalene 之指紋圖譜也有極大之差異，於中 油各級汽油中，皆明顯含有 C0-naphthalene、C1-naphthalene、C2-naphthalene 及 C3-naphthalene，台亞則僅含有 C0-naphthalene 及 C1-naphthalene，此差異性經過 75 天自然風化後仍然存在，但在經過 165 天放置室外之自然風化後，中油各級汽 油中含量已有明顯改變，因此應用該鑑識工具時，應先確認其風化作用影響程 度，以提高判釋之準確性，此判釋方法以及本研究所建立之汽油指標化合物，未 來可依不同風化程度選擇作為油品辨識之佐證工具。 本計畫之汽油污染場址環境法醫鑑識技術相關的分析技術應用於實場樣品 後，其結果顯示本計畫選用之各項鑑識指標化合物及比值參數皆能應用於評估風 化過程對市售汽油化學指紋特性及鑑識之影響，以及建立鑑識流程及鑑識指標化 合物。整體而言污染源的鑑定工作，宜搭配環境歷史背景調查、指紋圖譜、芳香 烴化合物分析等資料綜合研判將能得到較正確的鑑識結果。
計畫英文摘要	The advances in petroleum hydrocarbon fingerprinting and data interpretation methods and approaches in the last two decades have now allowed for detailed qualitative and quantitative characterization of spilled oils. Chemical fingerprinting is a powerful tool for hydrocarbon source identification and differentiation, when it is applied properly. However, in many cases, particularly for complex mixtures of fuel products or extensively weathered and degraded fuel residues, there is no single fingerprinting technique which can meet the objectives of forensic investigation and quantitatively allocate hydrocarbons to their respective sources. The objective of this project is to develop proper chemical analysis methodologies which are feasible to characterize and identify gasoline contaminated sites from environmental forensics prospect. In detail, the following tasks were included: (1) to obtain generic features and chemical composition of gasoline from Chinese Petroleum Company (CPC) and Formosa (FOR), (2) to establish tiered analytical approach, (3) to develop the fingerprinting and data interpretation techniques including protocol of identifying gasoline spill, (4) to evaluate effects of weathering on hydrocarbon fingerprinting, recognition of distribution patterns of petroleum hydrocarbons, fuel type screening and differentiation, and (5) to establish source-specific marker compounds, determination of diagnostic ratios of specific fuel constituents, application of various statistical and numerical analysis tools, and application of other analytical techniques. Various homologous series of hydrocarbons including volatile and semivolatile range of gasoline hydrocarbons were examined. In order to differentiate the chemical composition and to characterize aging processes of different grades of gasoline, the following parameters were measured: (1) benzene, toluene, ethylbenzene, and xylenes (BTEX), (2) C3 to C10 volatile hydrocarbons (3) C8 to C12 n-alkanes, (4) alkylbenzene and alkylnaphthalene, (5) alkylcyclohexanes, and (6) oxygenated additives. Each one of these groups of hydrocarbons has a different tolerance to environmental alternation by evaporation, dissolution, and biodegradation. For weathering effect studies, change of chemical constituent and biodegradation effect of gasoline contaminated soils are important factors to be considered, especially when there is a prolonged period of weathering processes. Methyl tert butl ether (MTBE), benzene, toluene, ethylbenzene, xylenes, n-propylbenzene, 1,2,3-trimethylbenzene, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, 1,3-diethylbenzene, 1,2,4,5-tetramethylbenzene and 1,2,3,5-tetramethylbenzene were recognized as indicator compounds in gasoline. Weathering effect onto 14 compounds along with total petroleum hydrocarbon (TPH), carbon preference index (CPI), weathering index (WI), benzene+toluene/ethylbenzene+xylenes (B+T/E+X) and methylnaphthalene ratio (MNR) were evaluated. The results indicated that TPH decreased with longer weathering time. TPH concentration decreased from 5229 mg/kg to 319 mg/kg in CPC gasoline (octane research number 98). It was contributed by partial depletion of n-alkanes. Weathering index demonstrated the similar trend from 3.97 to 0.57. It was indicated by loss of nalkanes and branched alkanes. To evaluate effects of weathering on hydrocarbon fingerprinting, and develop proper chemical analysis methodologies to characterize and identify gasoline contaminated sites from environmental forensics prospect. Composition difference of gasoline was observed in two major companies. Naphthalene, C1-naphthalene, C2- naphthalene, and C3-naphthalene were detected in all grades of CPC products. However, only C0-naphthalene and C1-naphthalene were found in FOR. With 180 days of weathering effect, such difference was existed. It may be used to discriminate between different samples of gasoline. While CPC gasoline (octane research number 98) with 165 days of weathering effect, it was contributed by partial depletion of C2-naphthalene. Therefore it is proper to confirm the impact of weathering effect for increasing the accuracy during application of the forensic tools. After the project of gasoline contaminated sites environmental forensics technology applied to the real samples. The results showed that each biomarkers and ratios in the project can evaluate weathered process on the effect of the Chemistry fingerprint characteristics of commercially available gasoline and forensics. To establish the fingerprinting and data interpretation techniques including protocol of identifying gasoline spill. Continuous tasks will be conducted to obtain information on gasoline type recognition patterns and on the degradation level, allowing for an estimate of residence time in gasoline contaminated soil. It is anticipated that information generated in this study will be adopted by decision makers for evaluation of liability of cleanup in gasoline contaminated sites in Taiwan.