Assessing the Impact of Wildfires on the Use of Black Carbon as an Indicator of Traffic Exposures in Environmental Epidemiology Studies.
Assessing the Impact of Wildfires on the Use of Black Carbon as an Indicator of Traffic Exposures in Environmental Epidemiology Studies.
复制标题
评估野火对使用黑碳作为环境流行病学研究中交通暴露的指标的影响。
DOI：
10.1029/2020gh000347
复制
发表时间：
2021-06
期刊：
影响因子：
4.8
通讯作者：
Magzamen S
中科院分区：
文献类型：
--
作者：
Martenies SE;Hoskovec L;Wilson A;Allshouse WB;Adgate JL;Dabelea D;Jathar S;Magzamen S
流行病学研究经常使用黑碳(BC)作为与交通相关的空气污染(TRAP)的替代指标。然而，野火烟雾(WFS)是BC的一个重要来源，当使用BC作为陷阱的替代品时，通常不考虑BC。在这里，我们研究了WFS基于BC测量来偏向诱捕器暴露评估的可能性。从2018年5月至11月，在整个科罗拉多州丹佛市地区收集了每周整合的BC样本。我们在抽样活动中收集了609个过滤器，其中35%是受WFS影响的。对于每个过滤器，我们计算了平均BC浓度。我们为每个采样位置评估了三个基于地理信息系统的诱捕器指标：300m缓冲区内的年平均日交通量，到高速公路的最小距离，以及300nm内的道路长度总和。受WFS影响的过滤器的BC浓度中值(中位数μg/m3，IQR=100.23μg/m3)比未受影响的过滤器(中位数g/m3，IQR=90.48μg/m3)高9%。在WFS事件期间，BC浓度升高，BC预期的空间梯度降低。我们进行了一项模拟研究，以估计圈闭暴露错误分类的区域WFS的结果。我们的结果表明，当WFS存在时，线性健康效应估计偏离了零。因此，依赖BC作为陷阱替代指标的暴露评估可能会受到野火事件的影响。考虑到与生物质燃烧相关的“棕色”碳的影响的替代指标可能会更好地将交通排放的影响与其他黑碳源的影响隔离开来。野火烟雾可能会改变城市内黑碳浓度的预期梯度，并对交通暴露评估产生偏差在我们的模拟健康影响研究中，野火烟雾引入的偏差导致的线性回归系数大于预期研究依赖于黑碳作为交通排放标志的研究需要考虑来自其他接近BC源的偏差的可能性
Epidemiological studies frequently use black carbon (BC) as a proxy for traffic‐related air pollution (TRAP). However, wildfire smoke (WFS) represents an important source of BC not often considered when using BC as a proxy for TRAP. Here, we examined the potential for WFS to bias TRAP exposure assessments based on BC measurements. Weekly integrated BC samples were collected across the Denver, CO region from May to November 2018. We collected 609 filters during our sampling campaigns, 35% of which were WFS‐impacted. For each filter we calculated an average BC concentration. We assessed three GIS‐based indicators of TRAP for each sampling location: annual average daily traffic within a 300 m buffer, the minimum distance to a highway, and the sum of the lengths of roadways within 300 m. Median BC concentrations were 9% higher for WFS‐impacted filters (median = 1.14 μg/m3, IQR = 0.23 μg/m3) than nonimpacted filters (median = 1.04 μg/m3, IQR = 0.48 μg/m3). During WFS events, BC concentrations were elevated and expected spatial gradients in BC were reduced. We conducted a simulation study to estimate TRAP exposure misclassification as the result of regional WFS. Our results suggest that linear health effect estimates were biased away from the null when WFS was present. Thus, exposure assessments relying on BC as a proxy for TRAP may be biased by wildfire events. Alternative metrics that account for the influence of “brown” carbon associated with biomass burning may better isolate the effects of traffic emissions from those of other black carbon sources. Wildfire smoke may alter the expected intraurban gradients in black carbon concentrations and bias traffic exposure assessments In our simulated health effects study, bias introduced by wildfire smoke resulted in larger than expected linear regression coefficients Studies relying on black carbon as a marker for traffic emissions need to consider the potential for bias from other proximate BC sources