台北都會區不同高度懸浮微粒濃度之變異

Aerosols at Street Level and Rooftop in Taipei

王秀娟(Shiou-Jiuan Wang) ； 王秋森(Chiu-Sen Wang)

《中華公共衛生雜誌》 14卷4期 (1995/08) Pp. 325-333

https://doi.org/10.6288/CJPH1995-14-04-03

摘要

懸浮微粒在台北都會區的濃度極高，尤其在交通頻繁的街道更是嚴重，故本研究主要在評估機動車輛對台北都會區不同高度、不同時段空氣中懸浮微粒的貢獻情形。使用微孔均勻沈積衝擊器於地下道、屋頂及建築物旁之不同高度採集懸浮微粒，並以微量天平及石墨爐原子吸收光譜儀分析懸浮微粒質量濃度及含鉛量。在人行道及不同高度之懸浮微粒及鉛濃度，白天和晚上兩採樣時段沒有顯著差異。對不同高度而言，環境中之懸浮微粒及鉛濃度隨高度升高而遞減，並且在愈高處遞減速率愈慢，在16至70公尺之間幾乎維持平穩。機動車輛對氣動直徑小於10μm之懸浮微粒的貢獻分率介於0.18-0.35之間，因採樣地點、高度、時間不同而異。細微粒（氣動直徑小於2.5μm）及粗微粒（氣動直徑在2.5-10μm之間）之機動車輛貢獻分率不同，人行道細微粒之交通貢獻分率介淤0.19-0.56之間，平均為036，租微粒之交通貢獻分率介於0.20-0.36之間，平均為0.26。

關鍵字

懸浮微粒 ； 鉛濃度 ； 機動車輛

並列摘要

This study's primary objective was to assess the contributions of automobile exhaust to the particulate air pollutants in the city of Taipei. Samples of airborne particles were taken with Micro-Orifice Uniform Deposit Impactors at an underpass and two nearby buildings of diffenent heights. The particle samples were weighed and analyzed for lead content by an atomic absorption spectrometer. The results for samples taken from 7 A.M.-7 P.M. did not differ significantly from those taken form 7 P.M.-7 A.M. of the same day. Rising from 1 to 16 meters in elevation, both the mass concentration and the lead content of airborne particles decrease rapidly. However, the rate of decrease dropped markedly at about 16 meters above ground. Particles sampled at the underpass during rainy days originated mainly from automobile exhaust, and therefore their lead content was used as the basis for estimating the contribution of automobile exhaust to airborne particles at street level and higher elevations. The contribution of automobile exhaust to airborne particles ranged from 18 to 35%, depending on location, elevation, and time of the day when the samples were taken. The fractions of contribution of automobile exhaust differed between fine particles (smaller than 2.5 μm in aerodynamic diameter) and coarse particles (2.5-10 μm). At 1 meter above the sidewalk, the contribution of automobile exhaust to fine particles ranged from 0.19 to 0.56, with an average of 0.36, and to coarse particles ranged from 0.20 to 0.36, with an average of 0.26.

並列關鍵字

aerosol ； lead ； automobile