College of Urban and Environmental Science, Peking University, Beijing, China.
Environ Sci Technol. 2011 Aug 15;45(16):6887-95. doi: 10.1021/es201443z. Epub 2011 Jul 18.
Atmospheric particulate matter with diameter <2.5 um (PM(2.5)) was collected at Peking University (PKU) in Beijing, China before, during, and after the 2008 Olympics and analyzed for black carbon (BC), organic carbon (OC), lower molecular weight (MW < 300) and MW302 Polycyclic Aromatic Hydrocarbons (PAHs), nitrated PAHs (NPAHs) and oxygenated PAHs (OPAHs). In addition, the direct and indirect acting mutagenicity of the PM(2.5) and the potential for DNA damage to human lung cells were also measured. Significant reductions in BC (45%), OC (31%), MW< 300 PAH (26-73%), MW 302 PAH (22-77%), NPAH (15-68%), and OPAH (25-53%) concentrations were measured during the source control and Olympic periods. However, the mutagenicity of the PM(2.5) was significantly reduced only during the Olympic period. The PAH, NPAH, and OPAH composition of the PM(2.5) was similar throughout the study, suggesting similar sources during the different periods. During the source control period, the parent PAH concentrations were correlated with NO, CO, and SO(2) concentrations, indicating that these PAHs were associated with both local and regional emissions. However, the NPAH and OPAH concentrations were only correlated with the NO concentrations, indicating that the NPAH and OPAH were primarily associated with local emissions. The relatively high 2-nitrofluoranthene/1-nitropyrene ratio (25-46) and 2-nitrofluoranthene/2-nitropyrene ratio (3.4-4.8), suggested a predominance of photochemical formation of NPAHs through OH-radical-initiated reactions in the atmosphere. On average, the ∑NPAH and ∑OPAH concentrations were 8% of the parent PAH concentrations, while the direct-acting mutagenicity (due to the NPAH and OPAH) was 200% higher than the indirect-acting mutagenicity (due to the PAH). This suggests that NPAH and OPAH make up a significant portion of the overall mutagenicity of PM(2.5) in Beijing.
在中国北京的北京大学（PKU），在 2008 年奥运会之前、期间和之后采集了直径小于 2.5 微米的大气颗粒物（PM(2.5)），并对其进行了分析，以测定黑碳（BC）、有机碳（OC）、低分子量（MW<300）和 MW302 多环芳烃（PAHs）、硝化多环芳烃（NPAHs）和含氧多环芳烃（OPAHs）。此外，还测量了 PM(2.5)的直接和间接致突变性以及对人肺细胞造成 DNA 损伤的潜力。在源控制和奥运期间，BC（45%）、OC（31%）、MW<300 PAH（26-73%）、MW 302 PAH（22-77%）、NPAH（15-68%）和 OPAH（25-53%）的浓度均显著降低。然而，只有在奥运期间，PM(2.5)的致突变性才显著降低。整个研究期间，PM(2.5)中 PAH、NPAH 和 OPAH 的组成相似，表明不同时期存在相似的来源。在源控制期间，母体 PAH 浓度与 NO、CO 和 SO(2)浓度相关，表明这些 PAHs 与本地和区域排放有关。然而，NPAH 和 OPAH 浓度仅与 NO 浓度相关，表明 NPAH 和 OPAH 主要与本地排放有关。相对较高的 2-硝基芴/1-硝基芘比值（25-46）和 2-硝基芴/2-硝基芘比值（3.4-4.8）表明，大气中 OH 自由基引发的反应主要通过光化学反应形成 NPAHs。平均而言，∑NPAH 和∑OPAH 浓度分别为母体 PAH 浓度的 8%，而直接作用致突变性（由于 NPAH 和 OPAH）比间接作用致突变性（由于 PAH）高 200%。这表明 NPAH 和 OPAH 构成了北京 PM(2.5)整体致突变性的重要部分。
