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年度	107	專案性質	實驗性質
專案類別	研究專案	研究主題	自訂
申請機構	國立臺灣大學	申請系所	農業化學系
專案主持人	陳佩貞	職等/職稱	副教授
專案中文名稱	不同價態鉈之化學分析方法開發及於水域底泥環境宿命探討
中文關鍵字	一價鉈、三價鉈、高效能液相層析結合感應耦合電漿質譜儀、陽極析出伏安法、基質干擾
專案英文名稱	Establishing analytical methods for detecting monovalent and trivalent thallium in the aquifier and sediment porewater
英文關鍵字	Thallic, Thallous, HPLC-ICP-MS, ASV
執行金額	969,954元
執行期間	2018/1/10 至 2018/11/30
計畫中文摘要	隨著科技發展日新月異，許多新興科技元素（Technology-critical elements, TCEs）在新興產業中逐漸被開發及應用，然而，TCEs的環境宿命及健康風險目前所知非常有限。鉈 （Thallium, Tl）為對哺乳動物具高毒性之TCEs，因而被美國環保署列為優先列管毒害污染物。依據我國產業型態顯示，鉈可能藉由火力發電、水泥製造業、醫療檢驗、光學材料、半導體及高溫超導體等產業活動而進入水體環境，經空氣或水體傳輸後極可能蓄積於底泥或進入地下水層，進而造成持久性環境污染議題。底泥為許多污染物之最終受體，研究指出鉈具生物累積性，因此，水體或底泥中鉈污染可能透過食物鏈累積而產生生物放大效應，進而對人體健康產生潛在危害。鉈在環境中主要價態包括一價鉈（Thallous, Tl(I)）及三價鉈（Thallic, Tl(III)），國內目前針對不同價態鉈之環境流布及污染危害調查研究仍然相當有限，且鉈尚未受到任何行政管制規範，可能是缺乏高效能化學檢測方法有關。因此，建立針對不同價態鉈之環境檢測方法具高度重要性及急迫性，才得以進一步瞭解鉈於國內水體環境（尤其是底泥）之污染現況、流布、宿命與危害性等議題。本計畫建立不同價態鉈（一價鉈及三價鉈）之化學分析方法，包括高效能液相層析結合感應耦合電漿質譜儀（High performance liquid chromatography inductively coupled plasma mass spectrometry, HPLC-ICP-MS）與陽極析出伏安法（Anodic stripping voltammetry, ASV）兩種化學分析技術，並以EPA稀釋水與4種環境水樣（酸性礦山排水、河川溪流、地下水、底泥孔隙水）為基質，評估兩種化學分析方法應用於檢測環境水樣中不同價態鉈物種之適用性與穩定性，並進一步探討不同環境基質條件（如pH值、陰離子與有機質）對水中三價鉈穩定性之影響。研究結果顯示，兩種方法皆能檢測不同價態鉈，然而，HPLC-ICP-MS於分析環境水樣中不同價態鉈之敏感度、準確度與適用性均優於ASV法，因其受到樣品基質之影響較小，故更能夠準確地定性定量Tl(I)及Tl(III)之濃度。此外，Tl(III)於低pH值（pH < 5）及添加DTPA之狀況下能夠穩定存在於水中。本計畫成功建立適用於分析環境水樣之化學分析方法，未來可擴大應用於檢測國內各水體及底泥環境之鉈的流布資訊，並據以深入了解不同價態鉈物種在自然環境中穩定性及可能宿命。
計畫英文摘要	Thallium (Tl) belongs to technology-critical elements (TCEs), which include a class of trace elements, increasingly produced and used in a variety of industries and manufactures worldwide. Tl is also a priority pollutant suggested by the U.S. EPA because it has high toxicity to mammals. Tl can enter surface waters via human activities such as mining, burning of coal fired power plants or cement manufacturing and/or wastewater discharge from high technology industries such as optical, semiconductive and superconductive factories. However, the environmental fate of most TCEs (including Tl) and their hazardous impact on human health and aquatic ecosystems remain unclear. Tl exists in the environment as monovalent (Thallous, Tl(I)) or trivalent (Thallic, Tl(III)) state, and Tl(I) is the dominant species in the aqueous environments. Recent studies indicate that Tl(III) could stably exist in surface water under specific environmental conditions with high oxidation-reduction potential or special environmental matrices, and it may be more toxic than Tl(I). In this study, we aim to establish a reliable, effective and high throughput analytical strategy to assess the stability of different Tl species in mimic river water matrices and their potential occurrence in environmental samples. We have successfully developed two analytical methods including high performance liquid chromatography inductively coupled plasma mass spectrometry (HPLC-ICP-MS) and anodic stripping voltammetry (ASV) for identifying Tl speciation. As compared to the ASV method, we showed that the HPLC-ICP-M method have less interference from environmental matrices in quantifying different Tl speceis; therefore, HPLC-ICP-MS is a beter and more sensitive analytical approach for Tl speciation than ASV. Additionally, we showed that Tl(III) could be stabilized in synthetic environmental water matrices in the presence of lower pH levels (pH< 5) and addition of organic acids (DTPA). The outcomes from this study provide systematic analytical methodology and useful initial information about potential occurrence and fate of different Tl species in Taiwan’s aquatic environments. We will further use the established methods for assessing Tl contamination in environmental samples collcted from Taiwan’s watershed including surface water and sediment in the future.