【作者】 于英鹏；

【导师】 刘敏； 杨毅；

【作者基本信息】 华东师范大学 ， 自然地理学， 2014， 博士

【摘要】 城市环境系统受全球气候变化和区域环境恶化的共同影响,系统内部环境过程复杂、污染物理化过程多变。高速的城市生活和人类活动使得大量有毒有害污染物进入城市环境中。城市人口的快速增长和建成区面积的扩大使得城市生态系统极其脆弱,面临着诸多亟待解决的环境问题,城市环境的可持续发展问题任重而道远。因此,对城市环境介质中持久性有机污染物(Persistent Organic Pollutants, POPs)的富集、分布特征与源解析研究具有重要意义。本研究选取中国最大的工商业城市—上海作为研究区域,开展了城市特征环境介质(玻璃表面有机膜)]PAHs富集、空间分布特征与健康风险研究；揭示了不同季节玻璃表面PAHs含量的变化规律及影响机制；探讨了有机膜中PAHs垂向分布规律、室内和室外有机膜中PAHs分布差异；针对有机膜中PAHs潜在的污染物来源构建了上海市环境介质中PAHs污染源指纹成分谱,同时对城市大气中PM2.5、PM10与有机膜中PAHs的进行了对比分析。上海中心城区有机膜中PAHs浓度范围为1348.5～4007.9ng/m2,呈现出交通区>商业区>文教区>公园绿地的浓度梯度。有机膜中PAHs组分主要以3-4环为主,Phe、Fl、Pyr和Chry是主要的单体化合物。主要工业区有机膜中PAHs主要以Phe、Fl、Pyr、Chry和B[b+k]F为主,其中宝山工业区及其对照点以Nap和Phe的含量为最高,说明煤炭燃烧是该区域有机膜中PAHs的主要贡献源。对城区、郊区和农村梯度有机膜中PAHs累积机制进行了研究,发现有机膜中PAHs浓度在城区要高于郊区和农村,而郊区和农村的差异较小。造成这种差异的原因可能是城区大量的汽车尾气排放提高了空气中PAHs的含量。而农村地区大量秸秆焚烧产生的PAHs增加玻璃表面有机膜对AHs的吸附量。郊区受汽车尾气和秸秆焚烧的影响要小于城市和农村地区。不同季节有机膜中PAHs的污染源存在着变化。气温、降水、风向和湿度等气象条件对大气中PAHs含量变化的影响较大,污染物排放源和主导风向对空气中PAHs的环境过程起主导作用。春季,有机膜中PAHs高浓度值主要分布在上海南部和浦东新区北部,浦东新区东南部为低值区,说明春季玻璃表面PAHs主要受控于污染源的影响。夏季,基本上呈现北部宝山工业区、中部吴泾工业区和南部金山工业区为高浓度值区的格局,可见污染源是影响PAHs含量的主导因素。中心城区大部分退出了高浓度区,可能受到上海市夏季强烈的城市“热岛”和“雨岛”效应的影响,热岛环流将中心城区空气中的PAHs带到偏远的郊区沉降；“雨岛”效应则使空气中大部分PAHs通过湿沉降过程进入土壤或水体等环境介质中,使吸附到玻璃表面的PAHs含量减少。秋季,PAHs高浓度值区域较夏季呈现出扩张的趋势,中心城区PAHs的浓度升高,金山和奉贤区的农村地区的浓度值也较高,秋季上海城区周边农村地区的秸秆焚烧对玻璃表面PAHs的吸附累积过程影响很大。冬季,PAHs高浓度范围主要在上海市中北部(包括吴泾工业区和宝山工业区)。上海市冬季主要以西北或东北风为主,金山工业区排放的PAHs随风迁移到下风向的钱塘江河口区或者进入浙江省,而对本地的影响减小。各季节玻璃表面PAHs基本以Phe、F1、Pyr、Chry为主。秋季Nap的含量高于其它季节,特别在农村地区体现的尤为明显,说明秸秆焚烧是农村地区秋季空气中PAHs的主要来源。不同季节不同功能区PAHs组分差异较大,说明在排放源基本不变的情况下,气象条件是影响PAHs组分变化的主导因素。不同季节不同功能区：PAHs的污染源存在差异,除来源于常规的燃煤和汽车尾气外,建筑土方、土壤风沙和扬尘也是不可忽视的玻璃表面PAHs二次污染源。对玻璃表面有机膜中PAHs垂向分布特征的分析发现,随着建筑物楼层的增加,PAHs含量呈现先增加后降低的趋势,说明随着楼层的增高空气中气态和颗粒态PAHs的含量逐渐增加,暗示着存在一个相对上下楼层较高的PAHs污染层。1～10层楼房PAHs与TOC存在很好的相关性,而11～17层PAHs与TOC则呈现相反的波动性。室内玻璃表面PAHs的含量要低于室外,低环PAHs在室内和室外玻璃表面的富集含量相当,而室外玻璃表面高环PAHs含量要高于室内。针对玻璃表面PAHs潜在的污染源,构建了上海市特征介质中PAHs源成份谱。宝山和金山工业区路面尘与降尘不同粒径颗粒物中PAHs的组分相似,主要以Phe、F1、 Pyr、Chry、B[b+k]F和BaP为主,说明这些单体PAH是表征工业区路面尘和降尘源的标志物。不同的燃烧环境下,秸秆和野草燃烧产物中PAHs组分均以低环为主(Nap、Phe)。柴油车(卡车和客车)排气管凝结物中PAHs以Nap、Phe、F1和Pyr为主,汽油车(小汽车)则以F1、Pyr、BaA、Chry、B[b+k]F、BaP、InP和BghiP等高环PAHs为主。从油烟机采集的油烟中PAHs的组分以Nap、Phe、F1和Pyr为主。从排烟风扇采集的油烟和烧烤残留物中PAHs组分则以Phe、F1、Pyr和Nap为主。土壤风沙尘以Phe、F1、Pyr和Chry为主,可作为建筑工地开挖土方和表土中PAHs判源标志物。冬季沿主导风向玻璃表面PAHs含量在85.7～343.7ng/m2之间,基本上城区和郊区高于农村地区。塘桥BaP含量要远高于其它样点。除申港外,其它样点3环PAHs所占比例最高,申港则以4环为主。PM2.5和PM10中PAHs含量分别为3.42～25.43ng/m3和3.56～26.69ng/m3,最高值出现在周浦(25.43ng/m3和26.69ng/m3),最低值出现在申港(3.42ng/m3和3.56ng/m3)。除申港外,其它样点PM2.5和PM10中PAHs主要以4环为主(27.47～41.1%),其次为5环(7.75～29.28%)。申港PAHs组成以3环PAHs为主(49.35%),其次为4环(27.47%),申港不同于其它样点的原因可能是受控于不同的污染物类型和大气中不同粒径颗粒物的含量,申港位于东海海边,空气湿度相对较大,也可能是影响空气中PAHs含量和组分特征的主要因子。雾霾期大气中PM2.5和PM1o中PAHs含量分别为16.57ng/m3和16.59ng/m3远高于非霾期。低环PAHs在玻璃表面与大气问很快达到动态平衡,但是高环PAHs很难或不存在平衡。中心城区、工业区、城-乡梯度和室内与室外玻璃表面有机膜中PAHs的TEQ值要低于办公室(1010ng/g),卧室(901ng/g)和餐厅(782ng/g)空调滤网灰尘中TEQ值。母体PAHs在环境过程中经常转化为其它形式PAHs(甲基化PAHs),因此仅参考母体PAHs的TEQ值来判读研究区的健康风险等级存在不准确性。终生致癌风险模型结果表明,吞食过程的致癌风险较小；不同年龄段人群吸入有机膜颗粒物的ILCRs值均高于1×104,说明因吸入而引起的致癌风险较高；而7个月-4岁年龄段儿童的皮肤接触暴露风险最大。更多还原

【Abstract】 Global climate change along with the regional environment deterioration pose an impact on urban system within which physical processes and chemical contaminants are becoming more and more complex. High-speed urban life and human activities produce large amounts of toxic and hazardous pollutants into the environment. The explosive growth of urban population makes the urban ecosystem extremely fragile, facing many environmental problems to be solved, and it is a long way to resolve sustainable problems. For the persistent organic pollutants (POPs) in the urban environment, it is of great significance to study its enrichment, distribution characteristics and source apportionment. This study selected China’s largest industrial and commercial city-Shanghai as target, analyzing the enrichment, spatial distribution characteristics, and health risks of the PAHs in organic film on the glass surface. It reveals the evolution pattern and mechanism of PAHs in different seasons in organic film on the glass surface, and also initially explores the distribution rules of PAHs on vertical glass surface, and the difference of enrichment and distribution between indoor and outdoor glass surface are also researched. In order to elucidate the potential pollutants sources of PAHs on glass surface, the component spectrum of source fingerprints within environment is constructed, and the coupling relationship between PM2.5, PM10and PAHs on the glass surface is discussed.The concentration of PAHs on the glass surface in shanghai downtown is ranging from1348.5to4007.9ng/m2, which shows the following concentrarion gradient:traffic zone>business zone>cultural and educational areas>garden. The constitute of the PAHs are most predominantly by3-4rings, and Phe, Fl, Pyr and Chry are the main congener compounds.. For three major industrial areas of shanghai, Phe、Fl、Pyr、Chr and B[b+k]F are the main congener compounds of the PAHs on the glass surface. The concentration of the Nap and Phe is highest in Baoshan area and that of the control point which indicates the coal burning is the main source for the burden of PAHs. Through the macroscopical investigation of PAHs on the glass surface in downtown, suburbs and countryside, it is found that the concentration of PAHs in suburbs is lower than that of in urban and rural areas. It is mainly because of automobile exhaust emissioned into the air in downtown, which increases the atmospheric concentration of PAHs. The straw burning in rural area can increase concentrations of PAHs absorbed on glass surface. But there is little effect in the suburb area.The source of the PAHs in organic film on the glass surface is changing with different seasons, and also the concentration of PAHs in the air is also influenced by temperature, precipitation, humidity, wind direction and other weather conditions. It is found that pollutant emission sources and dominant wind play the role on the PAHs in the air. The high concentration of PAHs in spring mainly exist in north shanghai and south of Shanghai Pudong New Area, whereas the southeast of Pudong new area is the low area. This spatial distribution pattern shows that PAHs on glass surface is mainly controlled by the pollutant source. When in summer, Baoshan industrial zone in north, Wujing industrial zone in central, and Jinshan industrial in south are the areas with high concentration. Thus pollutant source is the key factor affecting PAHs. In particular, most of the central city is out of the high concentration area and this phenomenon may be because of the intense "heat island" and "rain island" effect. The "heat island" circulation brings the PAHs in the central city to settle down in the distant suburbs, and "rain island" effect makes the PAHs into other environmental media such as soil or water bodies by wet deposition process that can reduce the amount absorbed on the glass. High concentration areas of PAHs in autumn are extending on the basis of that of summer situation. The concentration of PAHs in central city is increasing, and the rural areas in Jinshan and Fengxian also show the high concentration. As the result of straw burning in rural areas surrounding Shanghai urban areas, the burning can produce lots of PAHs which has great of significance on PAHs adsorbed on the glass surface. High concentrations of PAHs in winter mainly observe in North Central of Shanghai (including the Wu Jing industrial area and Baoshan Industrial area). In winter, north central of shanghai is the high concentration area (including Wujing area and Baoshan area). Northwest or northeast is the dominant wind direction, so the PAHs generated by Jinshan Chemical industial area may migrate to Qiantangjiang River or into Zhejiang province with help of the wind, which has little effect on shanghai. The PAHs on glass surface is mainly Phe, Fl, Pyr and Chry in each season. In particular, the concentration of Nap is the most abundant compound in autumn than in other seasons, especially in rural areas, which may be caused by the straw burning. The content of PAHs has great difference in different seasons and functional areas. It indicates that weather condition is the dominant factor that can affect composition changes of PAHs under the condition of the background sources basically unchanged. PAHs in different functional areas and different seasons has different source. Except the conventional sources from coal and automobile exhaust, building earthwork, sand soil and raise dust is also the secondary pollution source, which cannot be ignored.Through the investigation of vertical distribution characteristics of PAHs on the surface, the study shows that PAHs content increased at first and then decreased with the increase of building floors. It reveals with the increase of building floors, gaseous and particulate PAHs content increased, and also implies that there is a relatively PAHs contamination layer of high upper and lower floors. There is a good correlation between PAHs and TOC in lower floors, but has an opposite trend from11to17layer. Organic film on glass surface basically exhibits the cumulative growth in linear trend, and there is good correlation between accumulation of PAHs and TOC. Through the comparison of PAHs on the glass surface between indoor and outdoor, the indoor is lower than the outdoor, and low-ring PAHs has nearly the same concentration either indoor or outdoor. But mass percentage of high-ring PAHs is higher in outdoor than that of in indoor.For the study of PAHs’potential source of pollution, the study constructs source spectral composition of PAHs in features medium. The road dust and deposition dust have the same component of PAHs within different particles in both Baoshan and Jinshan industrial areas. They are mainly Phe、Fl、Pyr、Chry、B[b+k]F and BaP, and it shows these PAHs congeners are the markers of road dust and deposition dust in the industrial area. The components of PAHs from burning of straw and weeds are mainly comprised of low-ring PAHs. The coagulation from exhaust pipe of diesel vehicles (trucks and buses) is mainly Nap, Phe, Fl and Pyr. In the meantime, Fl, Pyr, BaA, Chry, B[b+k]F, BaP, InP, BghiP and other high-ring PAHs are the certain marker compounds in vehicles powered by gasoline. The PAHs of lampblack from hood are mostly comprised of Nap. The PAHs of fumes and barbecue residues from exhaust fan are mainly Phe, Fl, Pyr and Nap. The components of PAHs in soil dust are mainly Phe, Fl, Pyr and Chry. They can be used as source marker in excavation of earth and topsoil at construction site.The concentration of PAHs on glass surface which is along with dominant wind direction in winter is between85.7and43.7ng/m2, PAHs concentration in urban and suburban areas are higher than in rural area, and the concentration of BaP on glass surface in Tangqiao is higher than in other samples. Except Shengang which characterized by four-rings PAHs, the other three samples are mainly three-rings groups. The concentration of PAHs within PM2.5and PM10is3.42～25.43ng/m2and3.56-26.69ng/m. Highest point is observed at Zhoupu(25.43ng/m3and26.69ng/m3) and the lowest one is in Shengang (3.42ng/m3and3.56ng/m3). Except Shengang, PAHs within PM2.5and PM10in other samples are mainly characterized by four-ring (27.47～41.1%), followed by five-ring (7.75～29.28%). The components of PAHs in Shengang are characterized by three-ring (49.35%), followed by four-ring (27.47%). This difference may be caused by the different source of pollutant and different content of particles in the air. As shengang is adjacent to East China Sea where has a relatively high air humidity, this may be the main factor affecting the concentration and components of PAHs in the air. PAHs within PM2.5and PM10in haze period are16.57ng/m3and16.59ng/m3, respectively, which is much higher than the non-haze period. The low-ring PAHs can easily reach equilibrium between glass surface and atmosphere in a short period, whereas that of high-ring PAHs hardly or even no equilibrium.The TEQ values of PAHs in organic film on glass surface from central city, industrial zone, urban-rural gradient and indoor and outdoor, is lower than the values of PAHs in air conditioning filter dust from office (1010ng/g), bedroom (901ng/g) and restaurants (782ng/g). It indicates that staying indoor for a long time is more dangerous than outdoor, and it is better to have regular window ventilation to reduce the adverse effects on health from toxic organic pollutants. Parent PAHs in the environment process often converted to other forms PAHs (methylated PAHs), and therefore it is inaccurate to interpret ecological and health risks for this study, with only reference of the parent PAHs. The Lifetime cancer risk model results indicate that swallowing process has smaller cancer risk. The cancer risk relatively high due to inhalation organic particles for different age groups. Children between the age of seven months and four years old have the most serious exposure risk through skin contact organic film.更多还原