College of Environmental and Resource Sciences, Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Zhejiang University, Hangzhou 310058, China.
Zhejiang Ecological and Environmental Monitoring Center, Hangzhou 310012, China; Zhejiang Key Laboratory of Ecological and Environmental Monitoring, Forewarning and Quality Control, 310058, China.
Sci Total Environ. 2023 Jan 20;857(Pt 3):159674. doi: 10.1016/j.scitotenv.2022.159674. Epub 2022 Oct 22.
Continuous measurement of 98 volatile organic compounds (VOCs) was conducted during 2017-2019 at a regional background site (Shanxi) located at northeast of Zhejiang Province, YRD region, China. The average concentration of total VOCs (TVOCs) was 25.4 ± 18.4 ppbv, and an increasing trend (+12.2 %) was observed. Alkanes were the most abundant VOC group among all seasons, accounting for 43.5 % of TVOCs. Oxygenated VOCs (OVOCs), aromatics, halides and alkenes contributed 15.9 %, 15.7 %, 11.7 % and 10.3 % of TVOCs concentration, respectively. Biogenic VOCs (BVOCs) and OVOCs showed distinguished diurnal cycle from primary anthropogenic VOCs. Photochemical reactivity analysis based on ozone formation potential (OFP) and OH loss rate (L) indicated that aromatics and alkenes were the most significant contributor, respectively. Toluene, xylene (m/p- and o-), ethene and propene were the largest contributor of annual OFP, with the mean OFP being 33.8 ± 44.3 μg·m, 31.9 ± 32.1 μg·m, 9.29 ± 11.4 μg·m, 22.1 ± 21.3 μg·m and 12.8 ± 19.5 μg·m, respectively. Seven sources were identified with positive matrix factorization (PMF): petrochemical industry (13.8 %), biogenic emission (1.0 %), solvent usage-toluene (16.9 %), vehicular exhaust (43.8 %), Integrated circuits industry (3.8 %), solvent usage-C8 aromatics (10.9 %), and gasoline evaporation (9.8 %). Vehicular exhaust was the most significant source (43.8 %) during the whole measurement period. Solvent usage, petrochemical industry, and gasoline evaporation showed high temperature dependency. The integrated contribution of solvent usage and industrial processes were higher than vehicular exhaust during hot months. These sources also have higher chemical reactivities and can contribute more on O formation. Our results are helpful on determining the control strategies aiming at alleviating O pollution.
2017-2019 年期间，在中国东部浙江省东北部的长三角地区的山西省一个区域背景站点进行了 98 种挥发性有机化合物（VOCs）的连续测量。总挥发性有机物（TVOCs）的平均浓度为 25.4±18.4 ppbv，呈上升趋势（+12.2%）。烷烃是所有季节中最丰富的 VOC 组，占 TVOCs 的 43.5%。含氧挥发性有机化合物（OVOCs）、芳烃、卤代烃和烯烃分别占 TVOCs 浓度的 15.9%、15.7%、11.7%和 10.3%。生物源 VOCs（BVOCs）和 OVOCs 与主要人为源 VOCs 表现出明显的日变化。基于臭氧形成潜力（OFP）和 OH 损失率（L）的光化学反应分析表明，芳烃和烯烃是最重要的贡献者。甲苯、二甲苯（m/p-和 o-）、乙烯和丙烯是年 OFP 的最大贡献者，平均 OFP 分别为 33.8±44.3μg·m、31.9±32.1μg·m、9.29±11.4μg·m、22.1±21.3μg·m 和 12.8±19.5μg·m。利用正定矩阵因子分解（PMF）识别出 7 个来源：石化工业（13.8%）、生物排放（1.0%）、溶剂使用-甲苯（16.9%）、车辆尾气（43.8%）、集成电路工业（3.8%）、溶剂使用-C8 芳烃（10.9%）和汽油蒸发（9.8%）。在整个测量期间，车辆尾气是最重要的来源（43.8%）。溶剂使用、石化工业和汽油蒸发具有高温依赖性。在炎热的月份，溶剂使用和工业过程的综合贡献高于车辆尾气。这些来源的化学活性更高，对 O 形成的贡献更大。我们的研究结果有助于确定旨在缓解 O 污染的控制策略。
