Galarneau Elisabeth, Makar Paul A, Sassi Mourad, Diamond Miriam L
Air Quality Research Division, Environment Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada.
Environ Sci Technol. 2007 Jun 15;41(12):4205-13. doi: 10.1021/es062303k.
Polycyclic aromatic hydrocarbons (PAHs) are toxic compounds that are ubiquitous in the atmospheric environment. The input for an emissions processing system that was originally configured forthe study of criteria air pollutants was updated to calculate emissions of six semivolatile PAHs. The goal of the work was to produce emissions estimates with the spatial and temporal resolution needed to serve as input to a regional air quality model for southern Canada and the U.S. Such modeling is helpful in determining reductions in PAH emissions that may be necessary to protect human and ecosystem health. The total annual emission of the six PAHs (sigma6PAH) for both countries was estimated at 18 273 Mg/year. A total of 90% of these emissions arise from U.S. sources. The top six source types account for 73% of emissions and are related to metal production, open burning, incineration, and forest fires. The emission factors used in this study were derived from published compilations. Although this approach has the advantage of quality control during the compilation process, some compilations include factors from older studies that may overestimate emissions since they do not account for recent improvements in emission control technology. When compared to estimates published in the National Emissions Inventory (NEI) for 2002, the U.S. emissions in this study are higher by a factor of 4 (16 424 vs 4102 Mg/year). The cause of this difference has been investigated, and much of it is likely due to our use of data unavailable in the 2002 NEI but inferred here on the basis of the PAH emissions literature. Augmenting the 2002 NEI with this additional information would bring its reported annual emissions to 8213 Mg/year, which is within a factor of 2 of the estimates herein. The results presented for southern Canada are the first published values for all known PAH sources in that country.
多环芳烃(PAHs)是大气环境中普遍存在的有毒化合物。最初配置用于研究标准空气污染物的排放处理系统的输入数据已更新,以计算六种半挥发性多环芳烃的排放量。这项工作的目标是生成具有所需空间和时间分辨率的排放估计值,作为加拿大南部和美国区域空气质量模型的输入。这种建模有助于确定为保护人类和生态系统健康可能需要减少的多环芳烃排放量。两国六种多环芳烃的年总排放量(σ6PAH)估计为18273 Mg/年。这些排放总量的90%来自美国。前六大排放源类型占排放量的73%,与金属生产、露天焚烧、焚烧和森林火灾有关。本研究中使用的排放因子来自已发表的汇编。虽然这种方法在汇编过程中具有质量控制的优势,但一些汇编包括来自较旧研究的因子,这些因子可能高估了排放量,因为它们没有考虑到排放控制技术的最新改进。与2002年《国家排放清单》(NEI)中公布的估计值相比,本研究中的美国排放量高出4倍(16424 Mg/年对4102 Mg/年)。已对这种差异的原因进行了调查,其中大部分可能是由于我们使用了2002年NEI中没有的数据,但在此根据多环芳烃排放文献推断得出。用这些额外信息补充2002年NEI将使其报告的年排放量达到8213 Mg/年,这与本文的估计值相差不超过2倍。加拿大南部给出的结果是该国所有已知多环芳烃排放源的首次公布值。