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年度	108	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	國立台灣大學	申請系所	農業化學系
專案主持人	施養信	職等/職稱	教授
專案中文名稱	桃園地區多溴二苯醚高汙染土壤之持續調查與整治初探
中文關鍵字	土壤、多溴二苯醚、持久性汙染物
專案英文名稱	Continues monitoring and preliminary remediation investigation of polybrominated diphenyl ethers in high potential areas in Taoyuan
英文關鍵字	Soil, polybrominated diphenyl ethers, persistent organic contaminants.
執行金額	1,000,000元
執行期間	2018/12/20 至 2019/12/20
計畫中文摘要	多溴二苯醚(polybrominated diphenylethers, PBDEs)是一種溴化阻燃劑，常用於家用與工業產品中。然而斯德哥爾摩公約已將多溴二苯醚列為持久性有機污染物(persistent organic pollutants, POPs)，在106年5月則將十溴二苯醚(decabrominated diphenyl ether, DBDE)列入。此化合物不僅對環境有害，近年來有更多文獻證實PBDEs對人體等具有危害性與致癌性。根據102年農委會委託本實驗團隊所執行之計畫成果發現在我國桃園地區部分農作物中檢測出PBDEs之污染，並在部分使用DBDE之工廠附近土壤進行調查後檢測出PBDEs。根據本實驗室近年之農作物吸收污染物的試驗中發現PBDEs可能會藉由根部吸收方式傳輸至食用部位(莖葉)，PBDEs對土壤的污染將會透過植物吸收累積而對國人健康造成危害。先前對桃園地區使用DBDE之工廠附近土壤進行調查檢測後曾發現濃度高達2 ppm之PBDEs污染，且污染有向下移動之趨勢，而該工廠周圍有國小、農田以及住家等，此污染將影響人民生活與食物安全。 本計畫監測高PBDEs污染農田不同深度土壤中PBDEs含量，已完成高污染農田土壤兩次採樣，包含五月所採第一批次深度0-2公分、2-15公分及15-30公分土壤27件樣品，與八月所採第二批次深度0-2公分、2-15公分、15-30公分以及30-45公分土壤36件樣品。分析結果最高濃度有1.18 mg/kg，平均濃度為0.603 mg/kg，土壤仍然以DBDE為主，土壤表面DBDE濃度相較於前兩年有些微下降情形，而污染物有向深層土壤移動的趨勢。其中靠近工廠出風口之土壤的平均污染濃度偏高，距離較遠之土壤測值則較低。嘗試使用不同還原鐵移除DBDE試驗中，使用四種不同的鐵粉，其中L25與LIN較佳，在20天內可分別去除90%與70%之DBDE。而綜合試驗成果及成本考量後，顯示L25還原鐵粉較符合進一步應用。本計畫在150天試驗下未能從厭氧污泥中篩選出降解菌，改由現地土壤篩選出4株具PBDEs降解潛力之微生物，其中DD5與DD6較佳，兩者的降解速率常數分別為0.17 (day-1)與0.13 (day-1)。結合還原鐵進行DBDE移除試驗，結果顯示，還原鐵與微生物共同處理在48小時內可以穩定移除48%至58%之DBDE。本年度之調查成果，提供了桃園地區污染農田土壤之污染物濃度監測資料，並且還原鐵粉、微生物以及結合兩者降解之研究成果可作為後續整治技術之參考，有利於未來污染農田之整治規劃。
計畫英文摘要	Polybrominated diphenylethers (PBDEs) are one kind of brominated flame re-tardants, which were usually added to many household and industrial products. How-ever, some PBDEs were listed as persistent organic pollutants (POPs) in the Stock-holm Convention and decabrominated diphenyl ether (DBDE) was also listed in May 2017. Besides, PBDEs not only polluted the environment but also were confirmed hazardous and even carcinogenic to the human beings by more and more research in recent years. According to the results of the year-102 Council of Agriculture project performed by our lab, it was found that some crops in Taoyuan area were contami-nated with PBDEs. PBDEs were detected in the soil near the plant using DBDE. Based on our recent studies regarding transportation of PBDEs by plant root to edible parts, they have shown the potential uptake route of PBDEs to edible parts of plants, which could threaten human health. Previous investigations into the soil near the DBDE-utilizing plant in Taoyuan area have found PBDEs with concentrations up to 2 ppm and the pollution has a downward trend. Moreover, the contaminated plant is surrounded by school, farmland and houses, which will affect people's lives and food safety. In this project, the investigation is continued for monitoring of PBDEs at differ-ent depths in a highly PBDE contaminated farmland. We analyzed soil samples at depths 0-2 cm, 2-15 cm and 15-30 cm soils, totally 27 samples in the first batch in May and depths 0-2 cm, 2-15 cm, 15-30 cm and 30-45 cm, totally 36 samples in the second one in August. The highest DBDE value in soil is 1.18 mg/kg, and the average is 0.603 mg/kg. The farmland is still mainly DBDE contaminated, and the DBDE concentrations on the soil surface are found in a decreasing trend from 2016 to this year, while the depth distribution showed that PBDEs have leached toward deeper soil, indicating there is an urgent need to remediate the main contaminated farm. The average pollution concentra-tion of sites near the outlet of the factory is still high, and that at the farther away sites is low. In the tests of four kinds of zerovalent iron particles (ZVI), two ZVIs, L25 and LIN, have better efficiencies to remove 90% and 70% DBDE in 20 days, respectively. After several tests and cost-effect evaluations, the results showed that L25 ZVI is more applica-ble. In other aspect, we did not find microbial degraders in anaerobic sludges in 150 days but found four microorganisms with PBDEs degradation potential from this highly con-taminated soil. Among them, strains DD5 and DD6 have better removal with the rate con-stant of 0.17 (day-1) and 0.13 (day-1), respectively. Combing microorganisms with re-duced iron, the results showed that 48% to 58% DBDE was stably removed in 48 hours. Through this project, we monitored the content of PBDEs in contaminated farm-land soils and developed feasible remediation methods by using reduced iron powder, microoraganisms and combining both of them to facilitate the remediation in the future, which served as references for future remediation of PBDEs.