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大气挥发性有机物(volatile organic compounds, VOCs)是对流层臭氧以及二次气溶胶重要的前体物。苯系物(苯的衍生物总称)是VOCs的重要成分之一,其代表性物质有苯(Benzene)、甲苯(Toluene)、乙苯(Ethylbenzene)、二甲苯(Xylene),简称为BTEX。BTEX在环境空气中存在一定浓度分布且可能对人体造成危害。BTEX主要来源包括工业排放[1-3]、汽油挥发[4-5]、汽车尾气排放[6]等。近十几年来,我国开展了大量环境中的BTEX相关研究。早期主要采用吸附管或空气罐采样法[7],后期主要采用在线监测法进行BTEX的变化特征[8-11]、源解析[12-13]、臭氧生成潜势计算[14-17]、气溶胶生成贡献[18-20],以及健康风险[21-23]等研究。
尽管近些年已有不少苯系物的监测研究,但长期的观测数据仍然缺乏。本研究利用在线监测仪对北京市城区环境空气中的BTEX进行连续监测,分析其浓度水平、变化特征及对臭氧生成的潜在贡献,为北京市BTEX污染防治措施提供一定的科学依据。
北京城区大气苯系物变化特征及其环境意义
Exploring the variations in ambient BTEX at urban Beijing and its environmental implications
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摘要: 使用在线分析仪于2018年7月至2019年2月在北京城区对大气中的苯系物(BTEX)进行连续监测。监测期间BTEX平均体积分数为(5.05 ± 5.23) × 10−9,其中苯、甲苯、乙苯、间/对二甲苯及邻二甲苯的体积分数分别为(1.51 ± 1.70) × 10−9、(2.22 ± 2.05) × 10−9、(0.38 ± 0.46) × 10−9、(0.53 ± 0.56) × 10−9和(0.41 ± 0.46) × 10−9。BTEX浓度低于早前研究,季节变化也有所差异。BTEX日变化特征为白天浓度低于夜晚,夏季、秋季和冬季的浓度最低值分别出现在15:00、14:00和13:00;在冬季交通早高峰,BTEX出现明显的次峰值。根据最大增量反应活性法计算了BTEX各组分的臭氧生成潜势(OFP),其中甲苯OFP值最大,为(6.86±5.54) × 10−9。OFP值的季节变化特征与BTEX浓度变化一致,表现为秋季>冬季>夏季。通过特征物种比值法发现北京城区夏季受燃煤和溶剂挥发等综合影响,秋季主要受交通源排放的影响,冬季则主要受燃煤排放的影响。通过间/对二甲苯与乙苯比值发现北京夏季和冬季BTEX以新鲜排放源为主,秋季以老化气团为主。Abstract: BTEX in urban Beijing had been continuously measured using an on-line analyzer from July 2018 to February 2019. The average hourly mean mixing ratios of BTEX, benzene, toluene, ethylbenzene, m/p-xylene, and o-xylene were (5.05 ± 5.23) × 10−9, (1.51 ± 1.70) × 10−9, (2.22 ± 2.05) × 10−9, (0.38 ± 0.46) × 10−9, (0.53 ± 0.56) × 10−9 and (0.41 ± 0.46) × 10−9, respectively. Compared with earlier studies in urban Beijing, the concentrations of BTEX in our study showed lower values, and the seasonal changes also varied. The average diurnal variations were characterized by lower concentrations during daytime than at night, with the lowest concentrations occurring at around 15:00, 14:00, and 13:00 in summer, autumn, and winter, respectively. In the morning rush hours, there was an obvious BTEX peak in winter. According to the maximum incremental reaction activity method, the ozone formation potentials (OFP) of the BTEX components were obtained, of which the maximum value was found in toluene with a value of (6.86 ± 5.54) × 10−9. The seasonal variation in OFP values was consistent with BTEX concentrations, with higher values in autumn than in winter and summer. Through the characteristic species ratio method, it was found that BTEX were mainly affected by emissions from coal burning and solvent evaporation in summer, from traffic sources in autumn, and from coal burning in winter. BTEX were dominated by fresh emissions in summer and winter, and influenced by aged air in autumn according to the analysis on xylene to ethylbenzene ratios.
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Key words:
- BTEX /
- variations /
- ozone formation potential /
- characteristic species ratio
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表 1 BTEX物种之间的Pearson相关性
Table 1. The Pearson correlations (R) among BTEX components
苯
Benzene甲苯
Toluene乙苯
Ethylbenzene间/对二甲苯
m/p-Xylene邻二甲苯
o-Xylene苯 1.000 甲苯 0.865** 1.000 乙苯 0.794** 0.853** 1.000 间/对二甲苯 0.678** 0.628** 0.688** 1.000 邻二甲苯 0.698** 0.681** 0.802** 0.761** 1.000 注: **.在0.01级别(双尾),相关性显著。
Note: **. At 0.01 level (double tail), the correlation is significant.表 2 中国不同地区苯系物浓度的对比(单位: µg·m−3)
Table 2. Comparisons on the BTEX concentrations in different areas in China
采样点
Sampling
site监测方法
Monitoring
method采样时间
Sampling
period苯
Benzene甲苯
Toluene乙苯
Ethylbenzene间/对二甲苯
m/p-Xylene邻二甲苯
o-Xylene参考文献
Reference北京城区 吸附管采样GC/FID 2004.8 13.4 16.1 5.4 12.2 2.6 Gros等[27] 北京城区 采样器采样GC/MS 2005.8 5.62 11.4 4.62 8.86 4.04 LIU 等[12] 北京城区 在线GC/FID
GC/PID2006.8—9 6.87 9.38 3.62 4.69 1.91 Xie等[28] 北京城区 吸附管采样GC/PID 2008.8—9 2.37 3.97 1.92 3.51 1.90 Liu等[26] 北京城区 罐采样GC/MS 2008.10—
2009.108.9 12.4 4.0 3.5 2.7 孙杰等[9] 北京城区 Tenax-TA/吸附热解吸GC/PID 2009 4.43 7.03 2.72 4.18 2.06 王宇亮等[10] 北京城区 Tenax-TA/吸附热解吸GC/PID 2009.8—9 2.40 7.28 3.16 4.48 1.76 王宇亮等[10] 北京城区 被动采样器采样GC/FID 2008—2010
秋季平均7.3 10.2 4.7 3.6 — 曹函玉等[11] 北京城区 被动采样器采样GC/FID 2008—2010
冬季平均9.5 8.9 3.9 4.5 — 曹函玉等[11] 北京城区 在线GC/PID 2018.7—8 1.83 5.43 1.36 1.68 1.71 本研究 北京城区 在线GC/PID 2018.8—9 3.96 8.26 1.67 2.18 2.06 本研究 北京城区 在线GC/PID 2018.9—11 7.65 13.81 2.64 2.41 2.30 本研究 北京城区 在线GC/PID 2018.12—
2019.24.87 6.52 1.23 3.09 1.75 本研究 天津城区 在线GC/FID 2012.6—7 7.58 9.88 7.87 9.71 3.66 姚青等[14] 南京郊区 在线GC/FID 2013.3—
2014.210.10 10.11 8.82 2.90 1.84 林旭等[29] 南京郊区 在线GC/FID 2015.6.15—
7.158.64 9.82 6.07 2.05 1.51 刘静达等[30] 西安城区 吸附管采样GC/FID 2016.7—8 7.58 7.21 4.76 9.34 3.65 霍霄玮等[31] 西安城区 吸附管采样GC/FID 2015.12—
2016.114.93 19.52 6.52 10.16 4.14 霍霄玮等[31] 成都城区 在线GC/FID/MS 2016.8 4.37 11.96 2.84 7.01 2.08 徐晨曦等[32] 成都城区 在线GC/FID/MS 2017.8 1.35 5.10 1.19 3.08 0.89 徐晨曦等[32] 注:GC/PID、GC/FID、GC/MS分别表示气相色谱光电离子检测器、气相色谱火焰离子化检测器和气相色谱质谱检测器。
Note: GC/PID, GC/FID and GC/MS refer to gas chromatography with photoionization detector, flame ionization detector, and mass spectrometry detector, respectively.表 3 BTEX各组分的O3生成潜势
Table 3. Ozone formation potential of benzene series components
苯
Benzene甲苯
Toluene乙苯
Ethylbenzene间/对二甲苯
m/p-Xylene邻二甲苯
o-Xylene苯系物
BTEXMIR 0.4 2.7 2.7 7.4 6.5 OFP (×10−9) Jul. 0.30±0.24 3.01±2.14 0.74±1.06 3.02±3.50 3.33±2.80 10.40 Aug. 0.34±0.18 4.21±2.57 0.82±0.56 2.98±2.04 2.68±1.73 11.03 Summer 0.22±0.08 3.57±2.81 0.78±0.19 2.67±0.84 2.35±0.71 9.59 Sept. 0.63±0.54 5.74±3.96 1.06±1.19 3.15±2.77 3.54±3.99 14.12 Oct. 0.66±0.46 6.97±4.30 0.80±1.16 2.96±3.37 1.16±2.21 12.55 Nov. 1.35±0.82 14.64±6.23 2.68±1.79 5.40±3.56 4.79±3.11 28.86 Autumn 0.88±0.71 9.12±6.31 1.51±1.63 3.83±3.57 3.14±3.51 18.48 Dec. 0.41±0.37 4.06±3.59 0.80±0.87 5.09±4.83 2.70±2.83 13.06 Jan. 0.48±0.33 4.14±3.31 0.73±0.20 4.20±0.55 2.40±0.28 11.95 Feb. 0.87±1.21 4.83±6.77 0.55±0.92 4.09±6.47 1.82±3.19 12.16 Winter 0.57±0.74 4.31±4.65 0.71±0.83 4.94±5.17 2.41±2.82 12.94 All 0.73±0.68 6.86±5.54 1.12±1.24 4.53±4.11 2.65±2.96 15.89 注:1. 表中OFP数据表示(平均值 ±1标准偏差); 2. All表示整个监测期间.
Note: 1. The OPF data were the mean values ± 1 standard deviation; 2. All indicates the whole monitoring period. -
[1] LIU B SH, LIANG D N, YANG J M, et al. Characterization and source apportionment of volatile organic compounds based on 1-year of observational data in Tianjin, China [J]. Environmental Pollution, 2016, 218: 757-769. doi: 10.1016/j.envpol.2016.07.072 [2] HUI L R, LIU X G, TAN Q W, et al. Characteristics, source apportionment and contribution of VOCs to ozone formation in Wuhan, Central China [J]. Atmospheric Environment, 2018, 192: 55-71. doi: 10.1016/j.atmosenv.2018.08.042 [3] BOLDEN A L, KWIATKOWSKI C F, COLBORN T. New look at BTEX: Are ambient levels a problem? [J]. Environmental Science & Technology, 2015, 49(9): 5261-5276. [4] LIU X P, CHEN N, GUO H, et al. Ambient volatile organic compounds and their effect on ozone production in Wuhan, central China [J]. Science of the Total Environment, 2016, 541: 200-209. doi: 10.1016/j.scitotenv.2015.09.093 [5] OU J M, GUO H, ZHENG J Y, et al. Concentrations and sources of non-methane hydrocarbons (NMHCs) from 2005 to 2013 in Hong Kong: A multi-year real-time data analysis [J]. Atmospheric Environment, 2015, 103: 196-206. doi: 10.1016/j.atmosenv.2014.12.048 [6] WU F K, YU Y, SUN J, et al. Characteristics, source apportionment and reactivity of ambient volatile organic compounds at Dinghu Mountain in Guangdong Province, China [J]. Science of the Total Environment, 2016, 548/549: 347-359. doi: 10.1016/j.scitotenv.2015.11.069 [7] 李明珠, 李金娟, 王学中, 等. 空气中BTEX检测方法研究进展 [J]. 环境科学研究, 2019, 32(6): 948-958. LI M Z, LI J J, WANG X Z, et al. Research progress of BTEX detection methods in air [J]. Environmental Science Research, 2019, 32(6): 948-958(in Chinese).
[8] 张俊刚, 王跃思, 吴方堃, 等. 北京市大气中 BTEX工作日与非工作日的浓度变化 [J]. 环境化学, 2009, 28(1): 112-116. doi: 10.3321/j.issn:0254-6108.2009.01.024 ZHANG J G, WANG Y S, WU F K, et al. Variation of BTEX concentration in the atmosphere of Beijing on weekdays and non working days [J]. Environmental Chemistry, 2009, 28(1): 112-116(in Chinese). doi: 10.3321/j.issn:0254-6108.2009.01.024
[9] 孙杰, 王跃思, 吴方堃. 北京市BTEX的污染现状及变化规律分析 [J]. 环境科学, 2011, 32(12): 3531-3536. SUN J, WANG Y S, WU F K. Analysis of BTEX pollution status and change law in Beijing [J]. Environmental Science, 2011, 32(12): 3531-3536(in Chinese).
[10] 王宇亮, 张玉洁, 刘俊锋, 等. 2009年北京市苯系物污染水平和变化特征 [J]. 环境化学, 2011, 30(2): 412-417. WANG Y L, ZHANG Y J, LIU J F, et al. Pollution level and variation characteristics of Benzene Series in Beijing in 2009 [J]. Environmental Chemistry, 2011, 30(2): 412-417(in Chinese).
[11] 曹函玉, 潘月鹏, 王辉, 等. 2008~2010年北京城区大气BTEX的浓度水平及其O3生成潜势 [J]. 环境科学, 2013, 34(6): 2065-2070. CAO H Y, PAN Y P, WANG H, et al. Atmospheric BTEX concentration and O3 generation potential in Beijing urban area from 2008 to 2010 [J]. Environmental Science, 2013, 34(6): 2065-2070(in Chinese).
[12] LIU Y F, SONG M D, LIU X A, et al. Characterization and sources of volatile organic compounds (VOCs) and their related changes during ozone pollution days in 2016 in Beijing, China [J]. Environmental Pollution, 2020, 257: 113599.1-113599.12. [13] WANG G, CHENG SH Y, WEI W, et al. Characteristics and source apportionment of VOCs in the suburban area of Beijing, China [J]. Atmospheric Pollution Research, 2016, 7: 711-724. doi: 10.1016/j.apr.2016.03.006 [14] 姚青, 韩素芹, 蔡子颖, 等. 2012年夏季天津城区BTEX污染特征与臭氧潜势分析 [J]. 中国环境科学, 2013, 33(5): 793-798. doi: 10.3969/j.issn.1000-6923.2013.05.004 YAO Q, HAN S Q, CAI Z Y, et al. Analysis of BTEX pollution characteristics and ozone potential in Tianjin urban area in summer 2012 [J]. Chinese Journal of Environmental Sciences, 2013, 33(5): 793-798(in Chinese). doi: 10.3969/j.issn.1000-6923.2013.05.004
[15] 侯建平, 张文斌, 谭丽, 等. 重庆市典型城区大气VOCs的臭氧生成潜势与来源解析 [J]. 环境影响评价, 2018, 40(3): 71-75. HOU J P, ZHANG W B, TAN L, et al. Ozone generation potential and source analysis of atmospheric VOCs in typical urban areas of Chongqing [J]. Environmental Impact Assessment, 2018, 40(3): 71-75(in Chinese).
[16] 管贤贤, 齐安安, 雷春妮, 等. 兰州市大气苯系物的化学活性特征与健康风险评价 [J]. 环境科学学报, 2020, 40(2): 459-468. GUAN X X, QI A A, LEI C N, et al. Chemical activity characteristics and health risk assessment of atmospheric benzene homologues in Lanzhou [J]. Acta Scientiae Circumstantiae, 2020, 40(2): 459-468(in Chinese).
[17] 卢轩, 张瑞芹, 韩跞锎. 郑州市VOCs组分排放清单及其臭氧生成潜势[J]. 环境科学, 2020, 41(10): 4426-4435. LU X, ZHANG R Q, HAN Z. Emission inventory of VOCs and its ozone generation potential in Zhengzhou[J]. Environmental Science, 2020, 41(10): 4426-4435 (in Chinese).
[18] 刘丹, 解强, 张鑫, 等. 北京冬季雾霾频发期VOCs源解析及健康风险评价 [J]. 环境科学, 2016, 37(10): 3693-3701. LIU D, XIE Q, ZHANG X, et al. Source apportionment and health risk assessment of VOCs in winter haze prone period in Beijing [J]. Environmental Science, 2016, 37(10): 3693-3701(in Chinese).
[19] LI Q, SU G, LI C, et al. An investigation into the role of VOCs in SOA and ozone production in Beijing, China [J]. The Science of the Total Environment, 2020, 720(10): 137536. [20] 邹宇, 邓雪娇, 李菲, 等. 广州番禺大气成分站复合污染过程VOCs对O3与SOA的生成潜势 [J]. 环境科学, 2017, 38(6): 2246-2255. ZOU Y, DENG X J, LI F, et al. Formation potential of VOCs to O3 and SOA in the process of compound pollution at Guangzhou Panyu atmospheric composition station [J]. Environmental Science, 2017, 38(6): 2246-2255(in Chinese).
[21] 张文斌, 谭丽, 王赞春, 等. 重庆市沙坪坝区大气VOCs与健康影响评估[J]. 2017, 43(3): 43-48. ZHANG W B, TAN L, WANG Z CH, et al. Atmospheric VOCs and health impact assessment in Shapingba District of Chongqing[J]. 2017, 43(3): 43-48.
[22] STENEHJEM J S, KJARHEIM K, BRATVEIT M, et al. Benzene exposure and risk of lymphohematopoietic cancers in 25, 000 offshore oil industry workers [J]. British Journal of Cancer, 2015, 113(11): 1641. [23] MD A B, WARREN B. K. Ambient volatile organic compounds (VOCs) in communities of the Athabasca oil sands region: Sources and screening health risk assessment [J]. Environmental Pollution, 2018, 235: 602-614. doi: 10.1016/j.envpol.2017.12.065 [24] 张玉欣, 安俊琳, 王健宇, 等. 南京北郊大气BTEX变化特征和健康风险评估 [J]. 环境科学, 2017, 38(2): 454-460. ZHANG Y X, AN J L, WANG J Y, et al. Atmospheric BTEX variation characteristics and health risk assessment in the northern suburb of Nanjing [J]. Environmental Science, 2017, 38(2): 454-460(in Chinese).
[25] 赵若杰, 史建武, 韩斌, 等. 中国北方典型城市空气中苯系物的污染特征 [J]. 环境化学, 2012, 31(6): 778-782. ZHAO R J, SHI J W, HAN B, et al. Pollution characteristics of BTEX in the air of typical cities in northern China [J]. Environmental chemistry, 2012, 31(6): 778-782(in Chinese).
[26] LIU J F, MU Y J, ZHANG Y J, et al. Atmospheric levels of BTEX compounds during the 2008 Olympic Games in the urban area of Beijing [J]. Pubmed, 2009, 408(1): 109-116. [27] GROS V, SCIARE J, TONG Y. Air-quality measurements in megacities: focus on gaseous organic and particulate pollutants and comparison between two contrasted cities, Paris and Beijing [J]. Comptes Rendus Geosciences, 2007, 339: 764-774. doi: 10.1016/j.crte.2007.08.007 [28] XIE X, SHAO M, LIU Y, et al. Estimate of initial isoprene contribution to ozone formation potential in Beijing, China [J]. Atmospheric Environment, 2008, 42(24): 6000-6010. doi: 10.1016/j.atmosenv.2008.03.035 [29] 林旭, 朱彬, 安俊琳, 等. 南京北郊 VOCs 对臭氧和二次有机气溶胶潜在贡献的研究 [J]. 中国环境科学, 2015, 35(4): 976-986. LIN X, ZHU B, AN J L, et al. Potential contribution of VOCs to ozone and secondary organic aerosols in the northern suburb of Nanjing [J]. Chinese Journal of Environmental Sciences, 2015, 35(4): 976-986(in Chinese).
[30] 刘静达, 安俊琳, 张玉欣, 等. 南京工业区夏冬季节二次有机气溶胶浓度估算及来源解析 [J]. 环境科学, 2017, 38(5): 1734-1742. LIU J D, AN J L, ZHANG Y X, et al. Estimation and source apportionment of secondary organic aerosols in Nanjing Industrial Park in summer and winter [J]. Environmental Science, 2017, 38(5): 1734-1742(in Chinese).
[31] 霍霄玮, 薛科社, 许博健, 等. 西安市冬夏交通主干道环境空气中苯系物的污染特征 [J]. 环境污染与防治, 2017, 39(4): 423-438. HUO X W, XUE K S, XU B J, et al. Pollution characteristics of benzene series in ambient air of Xi'an winter and summer traffic trunk road [J]. Environmental Pollution and Prevention, 2017, 39(4): 423-438(in Chinese).
[32] 徐晨曦, 陈军辉, 韩丽, 等. 成都市 2017 年夏季大气 VOCs 污染特征、臭氧生成潜势及来源分析 [J]. 环境科学研究, 2019, 32(4): 620-625. XU C X, CHEN J H, HAN L, et al. Pollution characteristics, ozone generation potential and sources of atmospheric VOCs in Chengdu in the summer of 2017 [J]. Environmental Science Research, 2019, 32(4): 620-625(in Chinese).
[33] ATKINSON R, AREY J. Atmospheric degradation of volatile organic compounds [J]. Chemical Reviews, 2003, 103(12): 4605. doi: 10.1021/cr0206420 [34] WILLIAM P L, CARTER. A detailed mechanism for the gas-phase atmospheric reactions of organic compounds [J]. Atmospheric Environment, 2007, 24(3): 481-518. [35] 贾龙, 葛茂发, 庄国顺, 等. 对流层夜间化学研究 [J]. 化学进展, 2006, Z2: 1034-1040. doi: 10.3321/j.issn:1005-281X.2006.07.023 JIA L, GE M F, ZHUANG G S, et al. Tropospheric nocturnal chemistry [J]. Chemical Progress, 2006, Z2: 1034-1040(in Chinese). doi: 10.3321/j.issn:1005-281X.2006.07.023
[36] 杨婷, 李丹丹, 单玄龙, 等. 北京市典型城区环境空气中苯系物的污染特征、来源分析与健康风险评价 [J]. 生态毒理学报, 2017, 12(5): 79-97. doi: 10.7524/AJE.1673-5897.20170217001 YANG T, LI D D, SHAN X L, et al. Pollution characteristics, source analysis and health risk assessment of BTEX in the ambient air of typical urban areas in Beijing [J]. Acta Ecotoxicologica, 2017, 12(5): 79-97(in Chinese). doi: 10.7524/AJE.1673-5897.20170217001
[37] BARLETTA B, SIMONE M, ISOBEL J, et al. Ambient mixing ratios of nonmethane hydrocarbons (NMHCs) in two major urban centers of the Pearl River Delta (PRD) region: Guangzhou and Dongguan [J]. Atmospheric Environment, 2008, 42(18): 4393-4408. doi: 10.1016/j.atmosenv.2008.01.028 [38] WILLIAM P L, CARTER. Development of ozone reactivity scales for volatile organic compounds [J]. Air & Waste, 1994, 44(7): 881-899. [39] 闫雨龙, 温彦平, 冯新宇, 等. 太原市城区臭氧变化特征及影响因素 [J]. 环境化学, 2016, 35(11): 2261-2268. doi: 10.7524/j.issn.0254-6108.2016.11.2016043001 YAN Y L, WEN Y P, FENG X Y, et al. Characteristics and influencing factors of ozone change in Taiyuan City [J]. Environmental Chemistry, 2016, 35(11): 2261-2268(in Chinese). doi: 10.7524/j.issn.0254-6108.2016.11.2016043001
[40] DUAN J, TAN J, YANG L, et al,. Concentration, sources, and ozone formation potential of volatile organic compounds (VOCs) during ozone episode in Beijing [J]. Atmospheric Research, 2008, 88(1): 25-35. doi: 10.1016/j.atmosres.2007.09.004 [41] FERNANDEZ V V, LOPEZ M P, MUNIATEGUI L S, et al. C1 to C9 volatile organic compound measurements in urban air [J]. The Science of the Total Environment, 2004, 334-335: 167-176. doi: 10.1016/j.scitotenv.2004.04.037 [42] NELSON P F, QUIGLEY S M. The hydrocarbon composition of exhaust emitted from gasoline fueled vehicles [J]. Atmospheric Environment, 1984, 18(1): 79-87. doi: 10.1016/0004-6981(84)90230-0 [43] 李友平, 唐娅, 范中雨. 成都市大气环境VOCs污染特征及其健康风险评价 [J]. 环境科学, 2018, 39(2): 576-584. LI Y P, TANG Y, FAN Z Y. Pollution characteristics and health risk assessment of VOCs in Chengdu [J]. Environmental Science, 2018, 39(2): 576-584(in Chinese).
[44] 盛久江, 王飞, 李霞, 等. 北京城区夏冬两季 VOCs 时间变化和光化学特征的质子转移反应飞行时间质谱( PTR -TOF-MS)观测 [J]. 环境化学, 2019, 38(7): 1590-1599. doi: 10.7524/j.issn.0254-6108.2018092601 SHENG J J, WANG F, LI X, et al. Proton transfer reaction time of flight mass spectrometry (PTR-TOF-MS) observation of VOCs temporal variation and photochemical characteristics in Beijing urban area in summer and winter [J]. Environmental Chemistry, 2019, 38(7): 1590-1599(in Chinese). doi: 10.7524/j.issn.0254-6108.2018092601
[45] NAIROBI, KENYA. A review of 20 years’ air pollution control in Beijing[R]. United Nations Environment Programme, 2019. [46] ATKINSON R. Gas-phase tropospheric chemistry of organic compounds: A review [J]. Atmospheric Environment, 1990, 24(1): 1-41. doi: 10.1016/0960-1686(90)90438-S