EPA-98-FA11-03-D020

098

4,700 千元

2009/01/01

2009/12/31

許桂榮

監資處

江偉立

國立中央大學大氣物理所

環境資訊系統

長程輸送,,大氣汞,,戴奧辛,,水溶性離子,,金屬元素

long-range,transport,,atmospheric,mercury,,dioxins,,water-solubleions,,metal,elements

李崇德

鍾欣潔

03-4227151#65541

mazda_6846@hotmail.com

台灣位於東亞大氣污染與東南亞生質燃燒傳輸途徑的下風處，此區域氣象條件有利於將上游地區污染物（如酸性污染物、沙塵及生質燃燒等）傳送至台灣。隨著亞洲經濟高度發展，化石燃料消耗量與工業污染物排放量大幅增加，使得空氣污染物長程傳輸的影響日益重要。為瞭解空氣中有害物質長程傳輸對於台灣環境品質的衝擊，環保署規劃此計畫以達成下列目標：有害物質長程傳輸常規性監測可行性評估、建立有害物質長程傳輸監測技術、有害物質長程傳輸對我國環境衝擊之國際合作。由於空氣有害物質種類眾多，本研究先就汞與戴奧辛之監測進行評估。2008-2009年在馬祖、彭佳嶼、富貴角、竹子山、合歡山、鹿林山、恆春、蘭嶼及東沙等地共進行19次重點觀測，進行大氣汞與戴奧辛之採樣分析，每次重點觀測至少持續7天。除富貴角與合歡山，其他地點至少各進行2次重點觀測以探討長程傳輸之季節性變化。大氣汞濃度介於1.06與2.97 ng m-3，戴奧辛濃度介於0.42與390 fg-I-TEQ m-3；兩污染物之濃度皆出現季節性變化，通常夏季濃度較低，而冬、春季濃度較高，此與氣團來源之季節性變化有關，夏季西南季風帶來較乾淨的海洋性氣團，大氣汞與戴奧辛濃度偏低，而隨東北季風而來的大陸性氣團之有害物質濃度則偏高，顯示長程傳輸的影響。此外，本研究還分析鹿林山大氣氣膠(PM2.5與PM2.5-10)的化學組成，包含水溶性離子與金屬元素。2008-2009年分析結果顯示硫酸根與硝酸根離子為主要陰離子，銨離子為主要陽離子，鐵、鋁、鎂為主要金屬元素，而鉛則是最常偵測到的有害金屬元素。國際合作之進行，除了參加相關國際會議外，主要是與日本學者於2008年8月10-18日在日本富士山測候站進行大氣汞共同觀測，以及2009年3月26日至4月17日在韓國濟州島Gosan測站進行大氣汞與戴奧辛觀測。

長程輸送,,大氣汞,,戴奧辛,,水溶性離子,,金屬元素

EPA-98-FA11-03-D020.pdf

20MB

2010/2/1 上午 12:00:00

Taiwan is located downwind of the transport paths of the East Asian air pollution and the Southeast Asian biomass burning. Regional meteorological conditions are suitable for the transport of air pollutants (e.g. acidic pollutants, dusts, and biomass burning emissions) from upwind source regions to Taiwan. Due to the economy booming in Asia, regional fossil fuel consumption and industrial emission increase dramatically. Accordingly, the influence of the long-range transport of air pollutants is also increasing. To investigate the impact of long-range transported hazardous air pollutants (HAPs) on Taiwan’s environmental quality, Taiwan EPA drew up this project to achieve the following goals: feasibility assessment of the routine monitoring of long-range transported HAPs; establishment of the monitoring technology of long-range transported HAPs; international collaboration on the study of the impact of long-range transported air pollutants on Taiwan’s environment. Because there are many HAPs, mercury and dioxins were selected for evaluation of routine monitoring in this study. In 2008-2009, a total of 19 intensive observation periods (IOPs) were conducted at the following sites: Mazu, Pengjiayu, Fugueijiao, Mt. Bamboo, Mt. Hehuan, Hengchun, Lanyu, and Dongsha. Atmospheric mercury and dioxins were measured during each IOP. Each IOP lasted at least 7 days. Except at Fugueijiao and Mt. Hehuan where only 1 IOP was conducted, respectively, at least 2 IOPs were conducted at each of the other sites to investigate the seasonal variation in long-range transport. Concentrations of atmospheric mercury and dioxins were 1.06-2.97 ng m-3 and 0.42-390 fg-I-TEQ m-3, respectively. Seasonal variations in concentrations of both pollutants were observed, usually with lower concentrations in summer and higher concentrations in winter and spring. The seasonal variation in pollutant concentrations was related to the seasonal variation in air mass origins. In summer, the prevailing southwest monsoon brought clean marine air masses with lower concentrations of mercury and dioxins. On the other hand, in winter and spring, the prevailing northeast monsoon brought continental air masses, which contained higher HAPs concentrations. This study also investigated the chemical composition, including water-soluble ions and metal elements, of Mt. Lulin aerosol samples (PM 2.5 and PM 2.5-10). In 2008-2009, SO42- and NO3- were the major anions, while NH4+ was the major cation. Fe, Al, and Mg were the major metal elements. Pb was the most frequently detected hazardous metal element. Regarding the progress of international collaboration, besides the participation of relevant international conferences, the co-measurement of atmospheric mercury with Japanese researchers at Mt. Fuji weather station in Aug. 10-18, 2008 and the measurement of mercury and dioxins at Gosan in Jeju Island, Korea in Mar. 26-Apr. 17, 2009 were the principal tasks performed.

long-range,transport,,atmospheric,mercury,,dioxins,,water-solubleions,,metal,elements