Du Songyan, Wall Steven I, Cacia Dawn, Rodenburg Lisa A
Department of Environmental Sciences, Rutgers University, 14 College Farm Road, New Brunswick, New Jersey 08901, USA.
Environ Sci Technol. 2009 Mar 1;43(5):1287-92. doi: 10.1021/es802957y.
Passive air samplers were deployed at 32 sites across the Philadelphia metropolitan area to investigate the types and locations of atmospheric polychlorinated biphenyl (PCB) sources in a typical U.S. city. PCB levels varied over a factor of approximately 30 and displayed strong spatial gradients. Two regions of high PCB levels were observed, one in the center of Philadelphia and another on the city's south side. These two maxima are thought to represent urban vs. industrial sources. A Gaussian diffusion model was found to adequately describe the spatial gradients for the primary (center city) concentration maximum. Higher molecular weight PCBs were more prevalent at the more urban locations, in agreement with other urban gradient studies and suggesting that re-emission (i.e., secondary sources) of PCBs are important Positive matrix factorization analysis resolved two factors that are interpreted to represent light Aroclors and a heavier industrial source concentrated atthe secondary maximum on the city's south side. The results generally corroborate an earlier study in which data from the New Jersey Atmospheric Deposition Network site in Camden, NJ, was used to investigate source types and locations. Additionally, the non-Aroclor congener PCB 11 (3,3'-dichlorobiphenyl) was detected in all samples.
在费城大都市区的32个地点部署了被动空气采样器，以调查美国一个典型城市中大气多氯联苯（PCB）源的类型和位置。多氯联苯水平变化约30倍，并呈现出强烈的空间梯度。观察到两个多氯联苯高值区域，一个在费城中心，另一个在城市南侧。这两个最大值被认为分别代表城市源和工业源。发现高斯扩散模型能够充分描述主要（市中心）浓度最大值的空间梯度。与其他城市梯度研究一致，高分子量多氯联苯在城市程度更高的地点更为普遍，这表明多氯联苯的再排放（即二次源）很重要。正定矩阵因子分解分析解析出两个因子，分别被解释代表轻质氯丹和集中在城市南侧二次最大值处的较重工业源。研究结果总体上证实了一项早期研究，该研究使用新泽西州卡姆登的新泽西大气沉积网络站点的数据来调查源类型和位置。此外，在所有样本中均检测到了非氯丹同系物多氯联苯11（3,3'-二氯联苯）。
