空氣與落塵中戴奧辛之分布特性研究

HASH(0x1b37e6a0)

陳柏嘉(Bo-Chia Chen)

指導教授 ： 凌永健

國立清華大學/理學院/化學系/碩士(2008年)

https://doi.org/10.6843/NTHU.2008.00362

摘要

燃燒產生的戴奧辛分布於空氣中，人們再由呼吸將戴奧辛吸入體內。國內外已有相當多之空氣中戴奧辛研究，除了空氣之外，戴奧辛也會附著於空氣中的落塵，沈降於生活週遭環境，進而影響人們健康。目前國內尚無關於落塵中戴奧辛之組成及分布研究，本研究於桃園沿海地區大園和觀音地區和內陸地區中壢及鄰近地區採集空氣和落塵，分析桃園部分地區落塵中戴奧辛組成分布，並利用多變量分析探討不同地域、不同粒徑落塵之差異性，以及落塵與空氣中戴奧辛的關聯性。
分析結果顯示第一季(7~8月)及第二季(10~11月)空氣中戴奧辛平均毒性當量濃度分別為0.105和0.055 pg I-TEQ/Nm3，第一季及第二季落塵中戴奧辛沈降毒性通量分別為2.419和6.539 ng-TEQ/m2/yr，兩介質中之濃度與世界各國比較，均屬於低濃度範圍。主成分分析結果顯示，F採樣點之空氣與落塵中戴奧辛組成比較異常，懷疑附近有不明之排放源，其他採樣點之空氣中戴奧辛濃度組成分布與落塵中之分布不同；不同大小之粒徑落塵(大粒徑範圍: d > 2.7 □m；小粒徑範圍: 2.7 > d > 0.7 □m)中戴奧辛濃度組成不相同。小粒徑落塵中戴奧度沈降通量貢獻佔全部落塵不到10%，影響總落塵結果很小。

關鍵字

戴奧辛 ； 落塵 ； 分布

並列摘要

Dioxin generated from combustion widely distributed in the air and directly breathed by human. Simultaneously, the same dioxin might also adhere to dust in the air and deposited on our living environment and indirectly intake by human. Both dioxin exposure routes inevitably threat human health. Domestically, there are numerous researches about dioxin in air. On contrast, little is done about dioxin in dust. This study sampled air and dust from coast area and inland area in Taoyuan County and analyzed their dioxin composition and pattern. Multi-variable statistical analysis method was employed to study the difference in dioxin composition and pattern between dusts collected from different area and of different size as well as between dust and air.
The analytical results indicate that the average dioxin toxicity equivalent concentration in air was 0.105 and 0.055 pg I-TEQ/Nm3 for the first (July-August) and second (October-November) sampling campaign, respectively. The corresponding average dioxin deposition flux in dust was 2.419 and 6.539 ng-I-TEQ/m2/yr, respectively. Both concentration and flux are comparatively lower than those reported elsewhere in the world. Principal component analysis (PCA) of dioxin pattern in air and dust reveals abnormal dioxin concentration and at flux F-site, which was presumably correlated to an unknown neighboring emission source. PCA results of dust reveal area difference but not the air results, which is presumably due to air is more mobile and the composition is more uniform compared to the dust. Large dust (diameter > 2.7 □m) shows pattern similar to the total dust; whereas small (0.7 □m < diameter < 2.7 □m) presents different pattern. This implies dioxin in dust might come from different sources during the dust formation. The concentration contribution to total dust from small dust is less than 10%.

並列關鍵字

HASH(0x1b37f040) ； HASH(0x1b37f0e0) ； HASH(0x1b37f180)

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