Observations Confirm that Volatile Chemical Products Are a Major Source of Petrochemical Emissions in US Cities
Observations Confirm that Volatile Chemical Products Are a Major Source of Petrochemical Emissions in US Cities
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DOI：
10.1021/acs.est.0c05471
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发表时间：
2021-03-15
影响因子：
11.4
通讯作者：
Warneke, Carsten
中科院分区：
文献类型：
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作者：
Gkatzelis, Georgios, I;Coggon, Matthew M.;Warneke, Carsten
尽管几十年来空气污染有所下降，但美国城市地区仍然受到夏季臭氧和冬季颗粒物排放事件的影响。挥发性有机化合物（VOC）是已知的二次有机气溶胶（SOA）和光化学产生的臭氧的前体。过去几十年来，通过成功的监管措施，城市挥发性有机化合物排放源（包括道路交通排放）已大幅减少。这些VOC排放量的大幅减少导致了城市排放和VOC非燃烧源分布的变化，例如来自挥发性化学产品（VCPs）的VOC，现在占城市VOC负担的更高比例。鉴于排放源的这种转变，必须量化VCP和移动的源排放对城市污染的相对贡献。在此，地面站点和移动的实验室测量的挥发性有机化合物进行。两个地面站点位置具有不同的人口密度，博尔德，CO，和纽约市（纽约市），纽约州，选择，以评估VCPs的影响，在城市中的VCPs和移动的源排放的不同混合物。正矩阵分解被用来属性的化合物数百移动的和VCP为主的来源。VCP占主导地位的排放量分别占博尔德和纽约人为VOC排放量的42%和78%，而移动的源排放量分别占58%和22%。将分配的挥发性有机化合物排放量与基于燃料的车辆排放清单和VCP估计的排放量进行了比较，并同意在25%以内进行批量比较，在30%以内进行超过一半的单个化合物比较。评估的清单扩展到其他美国城市，它表明，50%至80%的排放量，反应性和城市人为VOCs的SOA形成潜力与VCP为主的来源，证明了它们在美国城市空气质量中的重要作用。
Despite decades of declining air pollution, urban U.S. areas are still affected by summertime ozone and wintertime particulate matter exceedance events. Volatile organic compounds (VOCs) are known precursors of secondary organic aerosol (SOA) and photochemically produced ozone. Urban VOC emission sources, including on-road transportation emissions, have decreased significantly over the past few decades through successful regulatory measures. These drastic reductions in VOC emissions have led to a change in the distribution of urban emissions and noncombustion sources of VOCs such as those from volatile chemical products (VCPs), which now account for a higher fraction of the urban VOC burden. Given this shift in emission sources, it is essential to quantify the relative contribution of VCP and mobile source emissions to urban pollution. Herein, ground site and mobile laboratory measurements of VOCs were performed. Two ground site locations with different population densities, Boulder, CO, and New York City (NYC), NY, were chosen in order to evaluate the influence of VCPs in cities with varying mixtures of VCPs and mobile source emissions. Positive matrix factorization was used to attribute hundreds of compounds to mobile- and VCP-dominated sources. VCP-dominated emissions contributed to 42 and 78% of anthropogenic VOC emissions for Boulder and NYC, respectively, while mobile source emissions contributed 58 and 22%. Apportioned VOC emissions were compared to those estimated from the Fuel-based Inventory of Vehicle Emissions and VCPs and agreed to within 25% for the bulk comparison and within 30% for more than half of individual compounds. The evaluated inventory was extended to other U.S. cities and it suggests that 50 to 80% of emissions, reactivity, and the SOA-forming potential of urban anthropogenic VOCs are associated with VCP-dominated sources, demonstrating their important role in urban U.S. air quality.