本研究旨在探討都會區不同型態街塵微粒中多環芳香烴化合物(PAHs)之含量、特性、負荷及洗街對PAHs減量效益。自都會區四種不同型態地區進行街道灰塵採樣分析與研究，以了解經交通工具夾帶、磨損、輾壓及其捲揚致街塵飛散或沉降後，分析不同粒徑砂土中PAHs之特性，並推估都會區受空氣污染衝擊，及含有害性空氣污染之粒狀物對人體健康所造成影響。研究結果顯示，在住宅區、商業區及工業區之街塵負荷較郊區高，可見其污染源大多來自交通工具排放與工廠製程，然其去塵效率(83.2~85%)並無明顯差異；另在街塵微粒中，以D1負荷最高(1.59~7.76 g/m2)，而其去塵效率(89.7~95.3%)卻以細微粒徑之坋土D4最佳。在街塵PAHs總含量分析中，以工業區之PAHs總含量最高(3538 ng/g)；另於街塵微粒PAHs含量分析中，大部分以BkF含量最高，次為CHR。因前述2種PAHs之半衰期、致癌率及毒性當量係數頗高，對環境破壞和人體健康的危害更是不容忽視。不論何者道路特性其街塵微粒中，中高分子量(四~六環) PAHs約佔95%以上，尤以五環PAHs含量所佔最多，惟細微粒徑之六環PAHs含量有明顯增加趨勢。雖街塵負荷去除效率、街塵PAHs負荷削減率及街塵PAHs之總毒性當量負荷削減率皆能達到75%以上，但研究發現街塵PAHs含量並未因洗街而有所改善。 The objective of the study was to investigate the concentration, characteristic, and load of polycyclic aromatic hydrocarbons (PAHs) in street dust and the reduction effective during washing street. By analyzing the characteristic of PAHs in different particle size of dust and sampling from the four different areas in Kaohsiung City to estimate the influence of the street dust flying and settling after carrying, damaging, and rolling by vehicles. In this study, to estimate the total amount of air pollution in Kaohsiung City and to evaluate the influence of particle to the human health was investigated.The results showed that the residential, commercial and industrial area of street dust loading was higher than the sub-urban. However, its reduction of dust street were between 83.2 - 85%. The most of the loading of street dust particle was D1, the average value was 1.59 - 7.76 g/m2, but the better reduction were D4 and between 89.7 - 95.3%. The total PAHs composition on street dust sampled in industrial area has the highest concentration (3538 ng/g) than other areas. In the PAHs concentration analyzing of the street dust particle, the main compositions were BkF and CHR. Because half of the aforementioned two kinds of PAHs, carcinogenic and toxic equivalency factors is high rate of environmental destruction and human health hazards can not be ignored.Whichever road characteristic of its street dust, high molecular weight (4- to 6-ring) PAHs accounting for more than 95%, the main composition of PAHs in street dust particle was 5-ring PAHs, however, the increasing trend of 6-ring PAHs was observed. Although the reduction effective of the street dust loading and PAHs loading with TEQ of PAHs were reaching to 75%, however the composition of PAHs that after washing street were not decreasing obviously.
