Noth Elizabeth M, Lurmann Fred, Northcross Amanda, Perrino Charles, Vaughn David, Hammond S Katharine
Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, 50 University Hall #7360, Berkeley, CA 94720-7360 USA.
Sonoma Technology, Inc., 1455 N. McDowell Blvd., Petaluma, CA 94954-6503.
Air Qual Atmos Health. 2016 Dec;9(8):899-908. doi: 10.1007/s11869-016-0399-y. Epub 2016 Apr 9.
Despite increasing evidence that airborne polycyclic aromatic hydrocarbon (PAH) exposures contribute to adverse health outcomes for sensitive populations, limited data are available on short-term intraurban spatial distributions for use in epidemiologic research. Exposure assessments for airborne PAHs are uncommon because air sampling for PAHs is a labor-, equipment-, and time-intensive task. To address this gap we measured wintertime PAH concentrations during 2010-2011 in Bakersfield, California, USA, a major city in the Southern San Joaquin Valley. Specifically, 58 96-hour integrated PAH samples were collected during 4 time periods at 14 locations from November 2010 to January 2011; duplicates were collected at two sites. We also collected elemental carbon (EC) at the same 14 sites and analyzed the two time periods with the highest ambient PAH pollution. We used linear regression models to quantify the relationship between potential spatial and temporal predictors of PAH concentrations. We found that wintertime PAH concentrations in Bakersfield, CA, are best predicted by meteorological variables and traffic proximity. Our model explains a moderate amount of the variability in the data (R=0.58), likely reflecting the major sources of PAHs in Bakersfield. We also observed that PAH concentrations were more spatially variable than EC concentrations. Comparing our data to historical monitoring data at one location in Bakersfield showed that the relatively low PAH concentrations during the 2010-2011 winter in Bakersfield is part of a long-term trend in decreasing PAH concentrations.
尽管越来越多的证据表明，空气中多环芳烃（PAH）暴露会对敏感人群的健康产生不良影响，但用于流行病学研究的城市内部短期空间分布数据却很有限。空气中多环芳烃的暴露评估并不常见，因为对多环芳烃进行空气采样是一项耗费人力、设备和时间的任务。为了填补这一空白，我们于2010 - 2011年冬季在美国加利福尼亚州贝克斯菲尔德市（南圣华金谷的一个主要城市）测量了多环芳烃浓度。具体而言，在2010年11月至2011年1月期间的4个时间段，在14个地点采集了58个96小时综合多环芳烃样本；在两个地点采集了重复样本。我们还在相同的14个地点收集了元素碳（EC），并分析了环境多环芳烃污染最高的两个时间段。我们使用线性回归模型来量化多环芳烃浓度潜在的空间和时间预测因子之间的关系。我们发现，加利福尼亚州贝克斯菲尔德市冬季的多环芳烃浓度最好由气象变量和与交通的接近程度来预测。我们的模型解释了数据中一定程度的变异性（R = 0.58），这可能反映了贝克斯菲尔德市多环芳烃的主要来源。我们还观察到，多环芳烃浓度在空间上的变异性比元素碳浓度更大。将我们的数据与贝克斯菲尔德市一个地点的历史监测数据进行比较表明，2010 - 2011年冬季贝克斯菲尔德市相对较低的多环芳烃浓度是多环芳烃浓度下降长期趋势的一部分。
