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Yang X, Song K, Guo S, Wang Y, Wang J, Peng D, Wen Y, Li A, Fan B, Lu S, Ding Y. Elucidating the unexpected importance of intermediate-volatility organic compounds (IVOCs) from refueling procedure. JOURNAL OF HAZARDOUS MATERIALS 2024; 471:134361. [PMID: 38669924 DOI: 10.1016/j.jhazmat.2024.134361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 04/10/2024] [Accepted: 04/18/2024] [Indexed: 04/28/2024]
Abstract
Evaporative emissions release organic compounds comparable to gasoline exhaust in China. However, the measurement of intermediate volatility organic compounds (IVOCs) is lacking in studies focusing on gasoline evaporation. This study sampled organics from a real-world refueling procedure and analyzed the organic compounds using comprehensive two-dimensional gas chromatography coupled with a mass spectrometer (GC×GC-MS). The non-target analysis detected and quantified 279 organics containing 93 volatile organic compounds (VOCs, 64.9 ± 7.4 % in mass concentration), 182 IVOCs (34.9 ± 7.4 %), and 4 semivolatile organic compounds (SVOCs, 0.2 %). The refueling emission profile was distinct from that of gasoline exhaust. The b-alkanes in the B12 volatility bin are the most abundant IVOC species (1.9 ± 1.4 μg m-3) in refueling. A non-negligible contribution of 17.5 % to the ozone formation potential (OFP) from IVOCs was found. Although IVOCs are less in concentration, secondary organic aerosol potential (SOAP) from IVOCs (58.1 %) even exceeds SOAP from VOCs (41.6 %), mainly from b-alkane in the IVOC range. At the molecular level, the proportion of cyclic compounds in SOAP (12.1 %) indeed goes above its mass concentration (3.1 %), mainly contributed by cyclohexanes and cycloheptanes. As a result, the concentrations and SOAP of cyclic compounds (>50 %) could be overestimated in previous studies. Our study found an unexpected contribution of IVOCs from refueling procedures to both ozone and SOA formation, providing new insights into secondary pollution control policy.
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Affiliation(s)
- Xinping Yang
- State Environmental Protection Key Laboratory of Vehicle Emission Control and Simulation, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Vehicle Emission Control Center, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Kai Song
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, International Joint Laboratory for Regional Pollution Control, Ministry of Education (IJRC), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Song Guo
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, International Joint Laboratory for Regional Pollution Control, Ministry of Education (IJRC), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.
| | - Yunjing Wang
- State Environmental Protection Key Laboratory of Vehicle Emission Control and Simulation, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Vehicle Emission Control Center, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
| | - Junfang Wang
- State Environmental Protection Key Laboratory of Vehicle Emission Control and Simulation, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Vehicle Emission Control Center, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Di Peng
- State Environmental Protection Key Laboratory of Vehicle Emission Control and Simulation, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Vehicle Emission Control Center, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Yi Wen
- China Automotive Technology and Research Center (CATARC), Beijing 100176, China
| | - Ang Li
- China Automotive Technology and Research Center (CATARC), Beijing 100176, China
| | - Baoming Fan
- TECHSHIP (Beijing) Technology Co., LTD, Beijing 100039, China
| | - Sihua Lu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, International Joint Laboratory for Regional Pollution Control, Ministry of Education (IJRC), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Yan Ding
- State Environmental Protection Key Laboratory of Vehicle Emission Control and Simulation, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
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Xiao S, Zhang Y, Zhang Z, Song W, Pei C, Chen D, Wang X. The contributions of non-methane hydrocarbon emissions by different fuel type on-road vehicles based on tests in a heavily trafficked urban tunnel. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 873:162432. [PMID: 36841415 DOI: 10.1016/j.scitotenv.2023.162432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 02/18/2023] [Accepted: 02/20/2023] [Indexed: 06/18/2023]
Abstract
Automobile exhaust is a major source of volatile organic compounds (VOCs) in metropolitan areas, yet it is difficult to accurately determine the contributions of different types of on-road vehicles. Tunnel tests are an effective way to measure real-world vehicle emissions, and the data collected are also suitable for receptor modeling to analyze the contributions of non-methane hydrocarbons (NMHCs) from different types of vehicles, as the closed environment ensures good mixing and minimal aging. In this study, tunnel tests were conducted inside a heavily trafficked city tunnel in Guangzhou in south China, and the positive matrix factorization (PMF) model was applied to the inlet-outlet incremental NMHC data. The results revealed that gasoline vehicles (GVs), Liquefied Petroleum Gas vehicles (LPGVs), and diesel vehicles (DVs) were responsible for 39 %, 45 % and 16 % of NMHCs, and 52 %, 23 %, and 24 % of the ozone formation potentials, respectively. LPGVs were the largest contributor of (56 %) alkanes, and GVs were the largest contributor of aromatics (61 %) and C2-C4 alkenes (55 %). With the video-recorded traffic counts the emissions of different fuel types are further compared on a per-vehicle-per-kilometer basis, and the results reveal that LPGVs and GVs were comparable in the OFPs of NMHCs emitted per kilometer, while on average a DV emitted 2.0 times more NMHCs than a GV with 2.4 times more OFPs. This study highlights substantial contribution of reactive alkenes and aromatics by DVs and the benefits of strengthening diesel exhaust control in terms of preventing ozone pollution.
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Affiliation(s)
- Shaoxuan Xiao
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China; CAS Center for Excellence in Deep Earth Science, Guangzhou, 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanli Zhang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China; CAS Center for Excellence in Deep Earth Science, Guangzhou, 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Zhou Zhang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Wei Song
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China; CAS Center for Excellence in Deep Earth Science, Guangzhou, 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chenglei Pei
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China; Guangdong Province Guangzhou Ecological Environment Monitoring Center Station, Guangzhou 510030, China
| | - Duohong Chen
- Guangdong Provincial Ecological Environment Monitoring Center, Guangzhou 510308, China
| | - Xinming Wang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China; CAS Center for Excellence in Deep Earth Science, Guangzhou, 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
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Wang S, Li Q, Duan K, Wang B, Zhu X, Wang X, Shen Y, Liu H, Ma Y. Profile of atmospheric VOC over the Yellow Sea, China: A tale of distribution, constraints, and sources. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 868:161634. [PMID: 36669669 DOI: 10.1016/j.scitotenv.2023.161634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 01/09/2023] [Accepted: 01/12/2023] [Indexed: 06/17/2023]
Abstract
In the winter of 2018-2019, 75 air samples were collected through four ship-borne measurements in the Yellow Sea (YS) to assess the levels, confinement processes, and source distribution of volatile organic compounds (VOCs). A total of 41 were eventually detected, which mainly were non-methane hydrocarbons (NMHCs), volatile halogenated hydrocarbons (VHCs), oxygenated volatile organic compounds (OVOCs), and volatile organic sulfur compounds (VSCs). Aromatics (31.93 %) and alkenes (11.04 %) in the atmosphere of the YS accounted for a larger proportion of NMHCs compared with the coastal areas. C3-C5 alkanes, propylene, and chloroform exhibited strong latitudinal gradients and opposite latitudinal distributions in the North and South YS, highlighting the strong contribution of regional outflow to YS's atmosphere. The level of Σ41VOCs increased significantly during the heavy pollution period with some chemical monomers detected, which was further enhanced by the emissions from industrial parks near the Liaodong Peninsula and the Shandong Peninsula. Five main VOC sources were identified by the Positive matrix factorization (PMF) model, which were industrial emissions (13.33 %), fuel use and volatilization (6.67 %), Freon R-22 emissions (33.33 %), oil and gas production (20.00 %), and solvent volatilization (26.67 %). These observations revealed the strong causal relationship between coastal air mass transport and the atmosphere in the marginal sea and emphasized that full attention should be paid to the unintentional and unorganized emission of chemical monomers in the industrial process.
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Affiliation(s)
- Shuang Wang
- Green Shipping and Carbon Neutrality Laboratory, College of Environmental Science and Engineering, Dalian Maritime University, 116026, No. 1 Linghai Road, Dalian, Liaoning Province, China
| | - Qingbo Li
- Green Shipping and Carbon Neutrality Laboratory, College of Environmental Science and Engineering, Dalian Maritime University, 116026, No. 1 Linghai Road, Dalian, Liaoning Province, China.
| | - Kuiquan Duan
- Green Shipping and Carbon Neutrality Laboratory, College of Environmental Science and Engineering, Dalian Maritime University, 116026, No. 1 Linghai Road, Dalian, Liaoning Province, China
| | - Baopeng Wang
- Green Shipping and Carbon Neutrality Laboratory, College of Environmental Science and Engineering, Dalian Maritime University, 116026, No. 1 Linghai Road, Dalian, Liaoning Province, China
| | - Xinyu Zhu
- Dalian Eco-environmental Affairs Service Center, 116026, No. 58 Lianshan Street, Shahekou District, Dalian, China
| | - Xuanya Wang
- China Academy of Transportation Science, 10029, No. 240, Huixinli, Chaoyang District, Beijing, China
| | - Yuxin Shen
- Green Shipping and Carbon Neutrality Laboratory, College of Environmental Science and Engineering, Dalian Maritime University, 116026, No. 1 Linghai Road, Dalian, Liaoning Province, China
| | - Hui Liu
- Green Shipping and Carbon Neutrality Laboratory, College of Environmental Science and Engineering, Dalian Maritime University, 116026, No. 1 Linghai Road, Dalian, Liaoning Province, China
| | - Ye Ma
- Green Shipping and Carbon Neutrality Laboratory, College of Environmental Science and Engineering, Dalian Maritime University, 116026, No. 1 Linghai Road, Dalian, Liaoning Province, China
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Chen T, Zhang P, Ma Q, Chu B, Liu J, Ge Y, He H. Smog Chamber Study on the Role of NO x in SOA and O 3 Formation from Aromatic Hydrocarbons. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:13654-13663. [PMID: 36136046 DOI: 10.1021/acs.est.2c04022] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
China is facing dual pressures to reduce both PM2.5 and O3 pollution, the crucial precursors of which are NOx and VOCs. In our study, the role of NOx in both secondary organic aerosol (SOA, the important constituent of PM2.5) and O3 formation was examined in our 30 m3 indoor smog chamber. As revealed in the present study, the NOx level can obviously affect the OH concentration and volatility distribution of gas-phase oxidation products and thus O3 and SOA formation. Reducing the NOx concentration to the NOx-sensitive regime can inhibit O3 formation (by 42%), resulting in the reduction of oxidation capacity, which suppresses the SOA formation (by 45%) by inhibiting the formation of O- and N-containing gas-phase oxidation products with low volatility. The contribution of these oxidation products to the formation of SOA was also estimated, and the results could substantially support the trend of SOA yield with NOx at different VOC levels. The atmospheric implications of NOx in the coordinated control of PM2.5 and O3 are also discussed.
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Affiliation(s)
- Tianzeng Chen
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Peng Zhang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qingxin Ma
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Biwu Chu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jun Liu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanli Ge
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hong He
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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Pei C, Yang W, Zhang Y, Song W, Xiao S, Wang J, Zhang J, Zhang T, Chen D, Wang Y, Chen Y, Wang X. Decrease in ambient volatile organic compounds during the COVID-19 lockdown period in the Pearl River Delta region, south China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 823:153720. [PMID: 35149077 PMCID: PMC8821021 DOI: 10.1016/j.scitotenv.2022.153720] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 01/30/2022] [Accepted: 02/03/2022] [Indexed: 05/22/2023]
Abstract
During the COVID-19 lockdown, ambient ozone levels are widely reported to show much smaller decreases or even dramatical increases under substantially reduced precursor NOx levels, yet changes in ambient precursor volatile organic compounds (VOCs) have been scarcely reported during the COVID-19 lockdown, which is an opportunity to examine the impacts of dramatically changing anthropogenic emissions on ambient VOC levels in megacities where ozone formation is largely VOC-limited. In this study, ambient VOCs were monitored online at an urban site in Guangzhou in the Pearl River Delta region before, during, and after the COVID-19 lockdown. The average total mixing ratios of VOCs became 19.1% lower during the lockdown than before, and those of alkanes, alkenes and aromatics decreased by 19.0%, 24.8% and 38.2%, respectively. The levels of light alkanes (C < 6) decreased by only 13.0%, while those of higher alkanes (C ≥ 6) decreased by 67.8% during the lockdown. Disappeared peak VOC levels in morning rush hours and the drop in toluene to benzene ratios during the lockdown suggested significant reductions in vehicle exhaust and industrial solvent emissions. Source apportioning by positive matrix factorization model revealed that reductions in industrial emissions, diesel exhaust (on-road diesel vehicles and off-road diesel engines) and gasoline-related emissions could account for 48.9%, 42.2% and 8.8%, respectively, of the decreased VOC levels during the lockdown. Moreover, the reduction in industrial emissions could explain 56.0% and 70.0% of the reductions in ambient levels of reactive alkenes and aromatics, respectively. An average increase in O3-1 h by 17% and a decrease in the daily maximum 8-h average ozone by 11% under an average decrease in NOx by 57.0% and a decrease in VOCs by 19.1% during the lockdown demonstrated that controlling emissions of precursors VOCs and NOx to prevent ambient O3 pollution in megacities such as Guangzhou remains a highly challenging task.
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Affiliation(s)
- Chenglei Pei
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangzhou Sub-branch of Guangdong Ecological and Environmental Monitoring Center, Guangzhou 510060, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Weiqiang Yang
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong Provincial Academy of Environmental Sciences, Guangzhou 510045, China
| | - Yanli Zhang
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; CAS Center for Excellence in Deep Earth Science, Guangzhou 510640, China
| | - Wei Song
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Shaoxuan Xiao
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Center for Excellence in Deep Earth Science, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jun Wang
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Center for Excellence in Deep Earth Science, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jinpu Zhang
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangzhou Sub-branch of Guangdong Ecological and Environmental Monitoring Center, Guangzhou 510060, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tao Zhang
- State Environmental Protection Key Laboratory of Regional Air Quality Monitoring, Guangdong Ecological and Environmental Monitoring Center, Guangzhou 510308, China
| | - Duohong Chen
- State Environmental Protection Key Laboratory of Regional Air Quality Monitoring, Guangdong Ecological and Environmental Monitoring Center, Guangzhou 510308, China
| | - Yujun Wang
- Guangzhou Sub-branch of Guangdong Ecological and Environmental Monitoring Center, Guangzhou 510060, China
| | - Yanning Chen
- Guangzhou Sub-branch of Guangdong Ecological and Environmental Monitoring Center, Guangzhou 510060, China
| | - Xinming Wang
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; CAS Center for Excellence in Deep Earth Science, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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Wang J, Zhang Y, Wu Z, Luo S, Song W, Wang X. Ozone episodes during and after the 2018 Chinese National Day holidays in Guangzhou: Implications for the control of precursor VOCs. J Environ Sci (China) 2022; 114:322-333. [PMID: 35459495 DOI: 10.1016/j.jes.2021.09.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 08/29/2021] [Accepted: 09/06/2021] [Indexed: 06/14/2023]
Abstract
The impact of reducing industrial emissions of volatile organic compounds (VOCs) on ozone (O3) pollution is of wide concern particularly in highly industrialized megacities. In this study, O3, nitrogen oxides (NOx) and VOCs were measured at an urban site in the Pearl River Delta region during the 2018 Chinese National Day Holidays and two after-holiday periods (one with ozone pollution and another without). O3 pollution occurred throughout the 7-day holidays even industrial emissions of VOCs were passively reduced due to temporary factory shutdowns, and the toluene to benzene ratios dropped from ∼10 during non-holidays to ∼5 during the holidays. Box model (AtChem2-MCM) simulations with the input of observation data revealed that O3 formation was all VOC-limited, and alkenes had the highest relative incremental reactivity (RIR) during the holiday and non-holiday O3 episodes while aromatics had the highest RIR during the non-pollution period. Box model also demonstrated that even aromatics decreased proportionally to levels with near-zero contributions of industrial aromatic solvents, O3 concentrations would only decrease by less than 20% during the holiday and non-holiday O3 episodes and ozone pollution in the periods could not be eliminated. The results imply that controlling emissions of industrial aromatic solvents might be not enough to eliminate O3 pollution in the region, and more attention should be paid to anthropogenic reactive alkenes. Isoprene and formaldehyde were among the top 3 species by RIRs in all the three pollution and non-pollution periods, suggesting substantial contribution to O3 formation from biogenic VOCs.
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Affiliation(s)
- Jun Wang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanli Zhang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Zhenfeng Wu
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shilu Luo
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wei Song
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Xinming Wang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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Liu X, Guo H, Zeng L, Lyu X, Wang Y, Zeren Y, Yang J, Zhang L, Zhao S, Li J, Zhang G. Photochemical ozone pollution in five Chinese megacities in summer 2018. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 801:149603. [PMID: 34416603 DOI: 10.1016/j.scitotenv.2021.149603] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 07/23/2021] [Accepted: 08/08/2021] [Indexed: 06/13/2023]
Abstract
To investigate photochemical ozone (O3) pollution in urban areas in China, O3 and its precursors and meteorological parameters were simultaneously measured in five megacities in China in summer 2018. Moderate wind speeds, strong solar radiation and high temperature were observed in all cities, indicating favorable meteorological conditions for local O3 formation. However, the unusually frequent precipitation caused by typhoons reaching the eastern coastline resulted in the least severe air pollution in Shanghai. The highest O3 level was found in Beijing, followed by Lanzhou and Wuhan, while relatively lower O3 value was recorded in Chengdu and Shanghai. Photochemical box model simulations revealed that net O3 production rate in Lanzhou was the largest, followed by Beijing, Wuhan and Chengdu, while it was the lowest in Shanghai. Besides, the O3 formation was mainly controlled by volatile organic compounds (VOCs) in most cities, but co-limited by VOCs and nitrogen oxides in Lanzhou. Moreover, the dominant VOC groups contributing to O3 formation were oxygenated VOCs (OVOCs) in Beijing and Wuhan, alkenes in Lanzhou, and aromatics and OVOCs in Shanghai and Chengdu. Source apportionment analysis identified six sources of O3 precursors in these cities, including liquefied petroleum gas usage, diesel exhaust, gasoline exhaust, industrial emissions, solvent usage, and biogenic emissions. Gasoline exhaust dominated the O3 formation in Beijing, and LPG usage and industrial emissions made comparable contributions in Lanzhou, while LPG usage and solvent usage played a leading role in Wuhan and Chengdu, respectively. The findings are helpful to mitigate O3 pollution in China.
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Affiliation(s)
- Xufei Liu
- Air Quality Studies, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, China
| | - Hai Guo
- Air Quality Studies, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, China.
| | - Lewei Zeng
- Air Quality Studies, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, China
| | - Xiaopu Lyu
- Air Quality Studies, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, China
| | - Yu Wang
- Institute for Environmental and Climate Research, Jinan University, Guangzhou, China
| | - Yangzong Zeren
- Air Quality Studies, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, China
| | - Jin Yang
- Air Quality Studies, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, China
| | - Luyao Zhang
- Air Quality Studies, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, China
| | - Shizhen Zhao
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, China
| | - Jun Li
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, China
| | - Gan Zhang
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, China
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Qin J, Wang X, Yang Y, Qin Y, Shi S, Xu P, Chen R, Zhou X, Tan J, Wang X. Source apportionment of VOCs in a typical medium-sized city in North China Plain and implications on control policy. J Environ Sci (China) 2021; 107:26-37. [PMID: 34412785 DOI: 10.1016/j.jes.2020.10.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Revised: 09/27/2020] [Accepted: 10/08/2020] [Indexed: 06/13/2023]
Abstract
Characteristics of atmospheric VOCs (volatile organic compounds) have been extensively studied in megacities in China, however, they are scarcely investigated in medium/small-sized cities in North China Plain (NCP). A comprehensive research on possible sources of VOCs was conducted in a medium-sized city of NCP, from May to September 2019. A total of 143 canister samples of 8 sites in Xuchang city were collected, and 57 VOC species were detected. The average VOC concentrations were 42.6 ± 31.6 μg/m3, with 53.7 ± 31.0 μg/m3 and 32.1 ± 27. 8 μg/m3, in the morning and afternoon, respectively. Alkenes and aromatics contributed 80% of the total ozone formation potential (OFP). Aromatics accounted for more than 95% of secondary organic aerosol potential (SOAP). VOCs were dominated by the local emission with significant transport from the southeast direction. PMF analysis extracted 6 sources, which were combustion (33.1%), LPG usage (19.3%), vehicular exhaust & fuel evaporation (15.8%), solvent usage (15.2%), industrial (9.11%) and biogenic (7.51%), respectively and they contributed 33.4%, 17.6%, 12.9%, 18.6%, 9.28% and 8.22% to the OFP, respectively. Combustion and LPG usage were the dominant VOC sources; and combustion, solvent usage and LPG usage were the main sources of OFP in Xuchang city, which were different to megacities in China with a high contribution from vehicular exhaust, solvent usage and industry, suggesting specific control strategies on VOCs need to be implemented in medium-sized city such as Xuchang city.
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Affiliation(s)
- Juanjuan Qin
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China; Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Xiaobo Wang
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanrong Yang
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuanyuan Qin
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shaoxuan Shi
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Peihua Xu
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Rongzhi Chen
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xueming Zhou
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China; Faculty of Earth Resources, China University of Geosciences, Wuhan 430074, China.
| | - Jihua Tan
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Xinming Wang
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
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9
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Feng J, Zhang Y, Song W, Deng W, Zhu M, Fang Z, Ye Y, Fang H, Wu Z, Lowther S, Jones KC, Wang X. Emissions of nitrogen oxides and volatile organic compounds from liquefied petroleum gas-fueled taxis under idle and cruising modes. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 267:115623. [PMID: 33254698 DOI: 10.1016/j.envpol.2020.115623] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 09/01/2020] [Accepted: 09/05/2020] [Indexed: 06/12/2023]
Abstract
Liquefied petroleum gas (LPG) as an alternative fuel is increasingly used in mainland China, few reports are however available about emissions from LPG-fueled vehicles. In this study, 26 LPG-fueled taxis in Guangzhou, south China were tested using a chassis dynamometer to obtain their emission factors of nitrogen oxides (NOx) and volatile organic compounds (VOCs) under idle and cruising (10-60 km h-1) modes. The emission factors of NOx on average increased with speed from 4.13 g kg-fuel-1 at idling to 71.1 g kg-fuel-1 at 60 km h-1 at a slope of 10.6 g kg-fuel-1 per 10 km h-1 increase in speed. Alkanes were the most abundant (71.9%) among the VOCs in the exhaust, followed by alkenes (25.2%), ethyne (2.7%), and aromatic species (0.2%). Emission factors of VOCs at idling averaged 8.24 g kg-fuel-1, higher than that of 6.23-7.36 g kg-fuel-1 when cruising at 10-60 km h-1, but their ozone formation potentials (OFPs) were lower at idling (15.8 g kg-fuel-1) than under cruising (19.1-23.8 g kg-fuel-1) largely due to higher emission of more reactive alkenes under cruising mode. Emissions of both NOx and VOCs increased significantly with mileages. Measured emission factors of NOx and reactive VOCs in this study suggested that replacing the gasoline-powered taxis with the LPG-fueled taxis with LPG-gasoline bi-fuel engines and no efficient after-treatment devices would not benefit in reducing the emissions of ozone precursors, and strengthening the emission control for LPG vehicles with dedicated LPG engines and after-treatment converters, as did in Hong Kong, could further benefit in reducing the emission of photochemically active species when using LPG as alternative fuels.
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Affiliation(s)
- Jingjing Feng
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yanli Zhang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China.
| | - Wei Song
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Wei Deng
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Ming Zhu
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zheng Fang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Yuqing Ye
- University of Science and Technology of China, Hefei, 230026, China
| | - Hua Fang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhenfeng Wu
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Scott Lowther
- University of Chinese Academy of Sciences, Beijing, 100049, China; Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ, United Kingdom
| | - Kelvin C Jones
- Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ, United Kingdom
| | - Xinming Wang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China; University of Chinese Academy of Sciences, Beijing, 100049, China
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10
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Huang X, Zhang Y, Wang Y, Ou Y, Chen D, Pei C, Huang Z, Zhang Z, Liu T, Luo S, Huang X, Song W, Ding X, Shao M, Zou S, Wang X. Evaluating the effectiveness of multiple emission control measures on reducing volatile organic compounds in ambient air based on observational data: A case study during the 2010 Guangzhou Asian Games. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 723:138171. [PMID: 32392684 DOI: 10.1016/j.scitotenv.2020.138171] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 03/22/2020] [Accepted: 03/22/2020] [Indexed: 06/11/2023]
Abstract
Volatile organic compounds (VOCs) play a crucial role in modulating air pollution by ozone and fine particles, particularly in urban areas. While in recent years short-term intervention actions for better air quality during big events in China did present good opportunities to examine the effectiveness of control measures in reducing anthropogenic VOCs emission, it is highly challenging to interpret the real effect of a specific control measure based on field monitoring data when a cocktail of control measures were adopted. Here we took the air quality intervention actions during the 16th Asian Games (AG) in Guangzhou as a case study to explore the impact of short-term multiple measures on VOCs reduction. The average mass concentrations of VOCs decreased by 52-68% during the AG. These percentages could not reflect emission reduction rates as the concentration might be also heavily impacted by dispersion conditions. Diagnostic ratios, such as methyl tert-butyl ether to carbon monoxide (MTBE/CO) and i-pentane/CO, decreased by over 60% during the AG, suggesting a substantial reduction in gasoline related emissions. A method linking emission reduction rates of two sources with their contribution percentages before and during the AG by using a receptor model was further formulated. With the available reduction rate of 34% for vehicular exhaust obtained during the traffic restriction drill in our previous study, VOCs emissions from gasoline evaporation and solvent use reduced by 45.7% and 13.6% during the AG, respectively. Total VOCs emissions decreased by 25.3% on average during the AG, and the emission control of vehicular exhaust, oil evaporation, and solvent use accounted for 17.0%, 6.3% and 2.0% of total VOCs emission reduction, respectively. This study presented an observed-based method with diagnostic/quantitative approaches to single out the effectiveness of each control measures in reducing VOCs emissions.
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Affiliation(s)
- Xinyu Huang
- School of Marine Sciences, Sun Yat-sen University, Guangzhou 510006, China; State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Yanli Zhang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
| | - Yujun Wang
- Guangzhou Environmental Monitoring Center, Guangzhou 510030, China
| | - Yubo Ou
- Guangdong Environmental Monitoring Center, Guangzhou 510308, China
| | - Duohong Chen
- Guangdong Environmental Monitoring Center, Guangzhou 510308, China
| | - Chenglei Pei
- Guangzhou Environmental Monitoring Center, Guangzhou 510030, China
| | - Zuzhao Huang
- Guangzhou Environmental Technology Center, Guangzhou 510180, China
| | - Zhou Zhang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Tengyu Liu
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Shilu Luo
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaoqing Huang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wei Song
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Xiang Ding
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Min Shao
- Institute for Environmental and Climate Research, Jinan University, Guangzhou 511443, China
| | - Shichun Zou
- School of Marine Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Xinming Wang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; University of Chinese Academy of Sciences, Beijing 100049, China
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11
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Zhang Y, Deng W, Hu Q, Wu Z, Yang W, Zhang H, Wang Z, Fang Z, Zhu M, Li S, Song W, Ding X, Wang X. Comparison between idling and cruising gasoline vehicles in primary emissions and secondary organic aerosol formation during photochemical ageing. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 722:137934. [PMID: 32208274 DOI: 10.1016/j.scitotenv.2020.137934] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 02/16/2020] [Accepted: 03/13/2020] [Indexed: 06/10/2023]
Abstract
Driving conditions are among the important factors determining gasoline vehicle emissions, yet their relation with exhaust-derived secondary pollutants is poorly understood. Here, we introduced exhaust from a gasoline vehicle under hot idling and cruising conditions into an indoor smog chamber by using a chassis dynamometer and investigated the formation of secondary organic aerosols (SOA) during photochemical ageing under light after characterizing the primary emission of non-methane hydrocarbons (NMHCs), nitrogen oxide (NOx) and primary organic aerosol (POA) in the dark. When compared to emission factors (EFs) at idling, during cruising at 20 km h-1 or 40 km h-1, the EFs of NMHCs decreased by more than an order of magnitude, while the EFs of NOx were more than doubled, resulting in a large drop in the NMHC-to-NOx ratios. The percentages of reactive alkenes and aromatic hydrocarbons also decreased from idling to cruising at 20 km h-1 to that at 40 km h-1. The emission factor of benzene, a carcinogenic compound, decreased more than 10 times from ~0.35 g kg-fuel-1 at idling to ~0.03 g kg-fuel-1 during cruising. During photochemical ageing of exhaust, substantial SOA was formed, and the SOA/POA ratios decreased from 52 to 92 at idling to 4-14 during cruising. Traditional aromatics could explain 30-64% of the measured SOA at idling but less than 15% of the measured SOA during cruising. Our results highlight that traffic congestion would greatly promote the emission of reactive volatile organic compounds and carcinogenic benzene from gasoline vehicles and also show that NMHCs as a target in gasoline vehicle emission tests cannot effectively represent the SOA and ozone formation potentials of the partially oxidized hydrocarbons from poorly functioning converters.
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Affiliation(s)
- Yanli Zhang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Wei Deng
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Qihou Hu
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Key Lab of Environmental Optics & Technology, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China
| | - Zhenfeng Wu
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Weiqiang Yang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Huina Zhang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhaoyi Wang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Zheng Fang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Ming Zhu
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Sheng Li
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wei Song
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Xiang Ding
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Xinming Wang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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12
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Song J, Zhang Y, Zhang Y, Yuan Q, Zhao Y, Wang X, Zou S, Xu W, Lai S. A case study on the characterization of non-methane hydrocarbons over the South China Sea: Implication of land-sea air exchange. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 717:134754. [PMID: 31837869 DOI: 10.1016/j.scitotenv.2019.134754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 09/07/2019] [Accepted: 09/29/2019] [Indexed: 06/10/2023]
Abstract
We present the characteristics of non-methane hydrocarbons (NMHCs) over the northern South China Sea (SCS) during a cruise campaign from September to October 2013. The mixing ratios of the total NMHCs ranged from 1.45 to 7.13 ppbv with an average of 3.54 ± 1.81 ppbv. Among the measured NMHCs, alkanes and aromatics were the major groups, accounting for 45.8 ± 8.7% and 28.7 ± 12.3% of the total NMHCs, respectively. Correlations of NMHCs with typical source tracers suggest that light alkanes and benzene were largely contributed by vehicular exhaust via long-range transport, while the other aromatics might be related to industrial sources and marine ship emissions. The spatial variations of NMHCs were observed with higher mixing ratios of NMHCs in the samples collected in the offshore areas than those in the coastal areas. Air mass back-trajectory analysis and diagnostic ratios of NMHCs show that the elevations of the total NMHCs were caused by the regional pollution transport from the southeast coast of China and/or southern China. The ozone formation potentials (OFPs) of NMHCs were calculated and the results show that the aromatics associated with marine ship emissions were the important contributors to the total OFP. This study provides useful information on the interaction between continental outflow and marine atmosphere.
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Affiliation(s)
- Junwei Song
- The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, and Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Yingyi Zhang
- The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, and Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China.
| | - Yanli Zhang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, China
| | - Qi Yuan
- The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, and Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Yan Zhao
- The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, and Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; Guangdong Environmental Monitoring Center, Guangzhou, China
| | - Xinming Wang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, China
| | - Shichun Zou
- School of Marine Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Weihai Xu
- Key Laboratory of Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
| | - Senchao Lai
- The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, and Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China.
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13
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Aromatic Hydrocarbons in Urban and Suburban Atmospheres in Central China: Spatiotemporal Patterns, Source Implications, and Health Risk Assessment. ATMOSPHERE 2019. [DOI: 10.3390/atmos10100565] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
: Ambient aromatic hydrocarbons (AHs) are hazardous air pollutants and the main precursors of ozone (O3). In this study, the characteristics of ambient AHs were investigated at an urban site (Ziyang, ZY) and a suburban site (Jiangxia, JX) in Wuhan, Central China, in 2017. The positive matrix factorization (PMF) model was used to investigate the sources of AHs, and a health risk assessment was applied to estimate the effects of AHs on human health. The concentrations of total AHs at ZY (2048 ± 1364 pptv) were comparable (p > 0.05) to that (2023 ± 1015 pptv) at JX. Source apportionment results revealed that vehicle exhaust was the dominant source of both, total AHs, and toluene, contributing 51.9 ± 13.1% and 49.3 ± 9.5% at ZY, and 44.7 ± 12.6% and 43.2 ± 10.2% at JX, respectively. Benzene was mainly emitted from vehicle exhaust at ZY (50.2 ± 15.5%), while it was mainly released from biomass and coal burning sources at JX (50.6 ± 16.7%). The health risk assessment results indicated that AHs did not have a significant non-carcinogenic risk, while the carcinogenic risks of benzene exceeded the regulatory limits set by the USEPA for adults (1 × 10−6) at both sites. Hence, controlling the emissions of vehicular and biomass/coal burning sources will be an effective way to reduce ambient AHs and the health risk of benzene exposure in this region. These findings will enhance our knowledge of ambient AHs in Central China and be helpful for local governments to formulate air pollution control strategies.
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14
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Zeng L, Fan GJ, Lyu X, Guo H, Wang JL, Yao D. Atmospheric fate of peroxyacetyl nitrate in suburban Hong Kong and its impact on local ozone pollution. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 252:1910-1919. [PMID: 31227349 DOI: 10.1016/j.envpol.2019.06.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 05/17/2019] [Accepted: 06/01/2019] [Indexed: 06/09/2023]
Abstract
Peroxyacetyl nitrate (PAN) is an important reservoir of atmospheric nitrogen, modulating reactive nitrogen cycle and ozone (O3) formation. To understand the origins of PAN, a field measurement was conducted at Tung Chung site (TC) in suburban Hong Kong from October to November 2016. The average level of PAN was 0.63 ± 0.05 ppbv, with a maximum of 7.30 ppbv. Higher PAN/O3 ratio (0.043-0.058) was captured on episodes, i.e. when hourly maximum O3 exceeded 80 ppbv, than on non-episodes (0.01), since O3 production was less efficient than PAN when there was an elevation of precursors (i.e. volatile organic compounds (VOCs) and nitrogen oxide (NOx)). Model simulations revealed that oxidations of acetaldehyde (65.3 ± 2.3%), methylglyoxal (MGLY, 12.7 ± 1.2%) and other oxygenated VOCs (OVOCs) (8.0 ± 0.6%), and radical cycling (12.2 ± 0.8%) were the major production pathways of peroxyacetyl (PA) radical, while local PAN formation was controlled by both VOCs and nitrogen dioxide (NO2). Among all VOC species, carbonyls made the highest contribution (59%) to PAN formation, followed by aromatics (26%) and biogenic VOCs (BVOCs) (10%) through direct oxidation/decomposition. Besides, active VOCs (i.e. carbonyls, aromatics, BVOCs and alkenes/alkynes) could stimulate hydroxyl (OH) production, thus indirectly facilitating the PAN formation. Apart from primary emissions, carbonyls were also generated from oxidation of first-generation precursors, i.e., hydrocarbons, of which xylenes contributed the most to PAN production. Furthermore, PAN formation suppressed local O3 formation at a rate of 2.84 ppbv/ppbv, when NO2, OH and hydroperoxy (HO2) levels decreased and nitrogen monoxide (NO) value enhanced. Namely, O3 was reduced by 2.84 ppbv per ppbv PAN formation. Net O3 production rate was weakened (∼36%) due to PAN photochemistry, so as each individual production and loss pathway. The findings advanced our knowledge of atmospheric PAN and its impact on O3 production.
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Affiliation(s)
- Lewei Zeng
- Air Quality Studies, Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong
| | - Gang-Jie Fan
- Department of Chemistry, National Central University, Taiwan
| | - Xiaopu Lyu
- Air Quality Studies, Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong
| | - Hai Guo
- Air Quality Studies, Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong.
| | - Jia-Lin Wang
- Department of Chemistry, National Central University, Taiwan
| | - Dawen Yao
- Air Quality Studies, Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong
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15
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Ling Z, He Z, Wang Z, Shao M, Wang X. Sources of methacrolein and methyl vinyl ketone and their contributions to methylglyoxal and formaldehyde at a receptor site in Pearl River Delta. J Environ Sci (China) 2019; 79:1-10. [PMID: 30784434 DOI: 10.1016/j.jes.2018.12.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2018] [Revised: 11/22/2018] [Accepted: 12/06/2018] [Indexed: 06/09/2023]
Abstract
Methacrolein (MACR) and methyl vinyl ketone (MVK) are two major intermediate products from the photochemical oxidation of isoprene, the most important biogenic volatile organic compound. In addition, MACR and MVK have primary emissions. Investigating the sources and evolution of MACR and MVK could provide helpful information for the oxidative capacity of the atmosphere. In this study, hourly measurements of isoprene, MACR, and MVK were conducted at a receptor site in the Pearl River Delta region (PRD), i.e., the Heshan site (HS), from 22 October to 20 November, 2014. The average mixing ratios of isoprene, MACR and MVK were 151 ± 17, 91 ± 6 and 79 ± 6 pptv, respectively. The daily variations and the ratios of MVK/MACR during daytime and nighttime suggested that other sources besides isoprene photooxidation influenced the MACR and MVK abundances at the HS. Positive matrix factorization was utilized to resolve the sources of MACR and MVK. Five sources were identified and quantified, including biogenic emissions, biomass burning, secondary formation, diesel, and gasoline vehicular emissions. Among them, secondary formation made the greatest contribution to observed MACR and MVK with average contributions of ~45% and ~70%, respectively. Through the yields of secondary products from the oxidation of MACR and MVK by the OH radical and the concentrations of MACR and MVK, it was found that methylglyoxal and formaldehyde were the main oxidation products of MACR and MVK at the HS site. Overall, this study evaluated the roles of primary emissions on ambient levels of MACR and MVK and advanced the understanding of photochemical oxidation of MACR and MVK in the PRD.
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Affiliation(s)
- Zhenhao Ling
- School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou, China; Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Guangzhou, China
| | - Zhuoran He
- School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou, China; Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Guangzhou, China
| | - Zhe Wang
- Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, China.
| | - Min Shao
- Institute for Environmental and Climate Research, Jinan University, Guangzhou, China
| | - Xuemei Wang
- Institute for Environmental and Climate Research, Jinan University, Guangzhou, China.
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16
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Increase of Atmospheric Methane Observed from Space-Borne and Ground-Based Measurements. REMOTE SENSING 2019. [DOI: 10.3390/rs11080964] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
It has been found that the concentration of atmospheric methane (CH4) has rapidly increased since 2007 after a decade of nearly constant concentration in the atmosphere. As an important greenhouse gas, such an increase could enhance the threat of global warming. To better quantify this increasing trend, a novel statistic method, i.e. the Ensemble Empirical Mode Decomposition (EEMD) method, was used to analyze the CH4 trends from three different measurements: the mid–upper tropospheric CH4 (MUT) from the space-borne measurements by the Atmospheric Infrared Sounder (AIRS), the CH4 in the marine boundary layer (MBL) from NOAA ground-based in-situ measurements, and the column-averaged CH4 in the atmosphere (XCH4) from the ground-based up-looking Fourier Transform Spectrometers at Total Carbon Column Observing Network (TCCON) and the Network for the Detection of Atmospheric Composition Change (NDACC). Comparison of the CH4 trends in the mid–upper troposphere, lower troposphere, and the column average from these three data sets shows that, overall, these trends agree well in capturing the abrupt CH4 increase in 2007 (the first peak) and an even faster increase after 2013 (the second peak) over the globe. The increased rates of CH4 in the MUT, as observed by AIRS, are overall smaller than CH4 in MBL and the column-average CH4. During 2009–2011, there was a dip in the increase rate for CH4 in MBL, and the MUT-CH4 increase rate was almost negligible in the mid-high latitude regions. The increase of the column-average CH4 also reached the minimum during 2009–2011 accordingly, suggesting that the trends of CH4 are not only impacted by the surface emission, however that they also may be impacted by other processes like transport and chemical reaction loss associated with [OH]. One advantage of the EEMD analysis is to derive the monthly rate and the results show that the frequency of the variability of CH4 increase rates in the mid–high northern latitude regions is larger than those in the tropics and southern hemisphere.
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Li S, Zhu M, Yang W, Tang M, Huang X, Yu Y, Fang H, Yu X, Yu Q, Fu X, Song W, Zhang Y, Bi X, Wang X. Filter-based measurement of light absorption by brown carbon in PM 2.5 in a megacity in South China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 633:1360-1369. [PMID: 29758888 DOI: 10.1016/j.scitotenv.2018.03.235] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 03/20/2018] [Accepted: 03/20/2018] [Indexed: 06/08/2023]
Abstract
Carbonaceous aerosols represent an important nexus between air pollution and climate change. Here we collected filter-based PM2.5 samples during summer and autumn in 2015 at one urban and two rural sites in Guangzhou, a megacity in southern China, and got the light absorption by black carbon (BC) and brown carbon (BrC) resolved with a DRI Model 2015 multi-wavelength thermal/optical carbon analyzer apart from determining the organic carbon (OC) and elemental carbon (EC) contents. On average BrC contributed 12-15% of the measured absorption at 405nm (LA405) during summer and 15-19% during autumn with significant increase in the LA405 by BrC at the rural sites. Carbonaceous aerosols, identified as total carbon (TC), yielded average mass absorption efficiency at 405nm (MAE405) that were approximately 45% higher in autumn than in summer, an 83% increase was noted in the average MAE405 for OC, compared with an increase of only 14% in the average MAE405 for EC. The LA405 by BrC showed a good correlation (p<0.001) with the ratios of secondary OC to PM2.5 in summer. However, this correlation was poor (p>0.1) in autumn, implying greater secondary formation of BrC in summer. The correlations between levoglucosan (a marker of biomass burning) and the LA405 by BrC were significant during autumn but insignificant during summer, suggesting that the observed increase in the LA405 by BrC during autumn in rural areas was largely related to biomass burning. The measurements of light absorption at 550nm presented in this study indicated that the use of the IMPROVE algorithm with an MAE value of 10m2/g for EC to approximate light absorption may be appropriate in areas not strongly affected by fossil fuel combustion; however, this practice would underestimate the absorption of light by PM2.5 in areas heavily affected by vehicle exhausts and coal burning.
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Affiliation(s)
- Sheng Li
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ming Zhu
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Weiqiang Yang
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Mingjin Tang
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Xueliang Huang
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Yuegang Yu
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Hua Fang
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xu Yu
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qingqing Yu
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaoxin Fu
- School of Environment and Resource, Southwest University of Science and Technology, Mianyang 621010, China
| | - Wei Song
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Yanli Zhang
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Xinhui Bi
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Xinming Wang
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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Zeng L, Lyu X, Guo H, Zou S, Ling Z. Photochemical Formation of C 1-C 5 Alkyl Nitrates in Suburban Hong Kong and over the South China Sea. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:5581-5589. [PMID: 29664616 DOI: 10.1021/acs.est.8b00256] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Alkyl nitrates (RONO2) are important reservoirs of atmospheric nitrogen, regulating nitrogen cycling and ozone (O3) formation. In this study, we found that propane and n-butane were significantly lower at the offshore site (WSI) in Hong Kong ( p < 0.05), whereas C3-C4 RONO2 were comparable to the suburban site (TC) ( p > 0.05). Stronger oxidative capacity at WSI led to more efficient RONO2 formation. Relative incremental reactivity (RIR) was for the first time used to evaluate RONO2-precursor relationships. In contrast to a consistently volatile organic compounds (VOC)-limited regime at TC, RONO2 formation at WSI switched from VOC-limited regime during O3 episodes to VOC and nitrogen oxides (NO x) colimited regime during nonepisodes. Furthermore, unlike the predominant contributions of parent hydrocarbons to C4-C5 RONO2, the production of C1-C3 RONO2 was more sensitive to other VOCs like aromatics and carbonyls, which accounted for ∼40-90% of the productions of C1-C3 alkylperoxy (RO2) and alkoxy radicals (RO) at both sites. This resulted from the decomposition of larger RO2/RO and the change of OH abundance under the photochemistry of other VOCs. This study advanced our understanding of the photochemical formation of RONO2, particularly the relationships between RONO2 and their precursors, which were not confined to the parent hydrocarbons.
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Affiliation(s)
- Lewei Zeng
- Air Quality Studies, Department of Civil and Environmental Engineering , The Hong Kong Polytechnic University , Hong Kong , China
| | - Xiaopu Lyu
- Air Quality Studies, Department of Civil and Environmental Engineering , The Hong Kong Polytechnic University , Hong Kong , China
| | - Hai Guo
- Air Quality Studies, Department of Civil and Environmental Engineering , The Hong Kong Polytechnic University , Hong Kong , China
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19
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Wang Y, Guo H, Zou S, Lyu X, Ling Z, Cheng H, Zeren Y. Surface O 3 photochemistry over the South China Sea: Application of a near-explicit chemical mechanism box model. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 234:155-166. [PMID: 29175477 DOI: 10.1016/j.envpol.2017.11.001] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2017] [Revised: 10/31/2017] [Accepted: 11/01/2017] [Indexed: 06/07/2023]
Abstract
A systematic field measurement was conducted at an island site (Wanshan Island, WSI) over the South China Sea (SCS) in autumn 2013. It was observed that mixing ratios of O3 and its precursors (such as volatile organic compounds (VOCs), nitrogen oxides (NOx = NO + NO2) and carbon monoxide (CO)) showed significant differences on non-episode days and episode days. Additional knowledge was gained when a photochemical box model incorporating the Master Chemical Mechanism (PBM-MCM) was applied to further investigate the differences/similarities of O3 photochemistry between non-episode and episode days, in terms of O3-precursor relationship, atmospheric photochemical reactivity and O3 production. The simulation results revealed that, from non-O3 episode days to episode days, 1) O3 production changed from both VOC and NOx-limited (transition regime) to VOC-limited; 2) OH radicals increased and photochemical reaction cycling processes accelerated; and 3) both O3 production and destruction rates increased significantly, resulting in an elevated net O3 production over the SCS. The findings indicate the complexity of O3 pollution over the SCS.
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Affiliation(s)
- Yu Wang
- Air Quality Studies, Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong
| | - Hai Guo
- Air Quality Studies, Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong.
| | - Shichun Zou
- School of Marine Sciences, Sun Yat-sen University, China.
| | - Xiaopu Lyu
- Air Quality Studies, Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong
| | - Zhenhao Ling
- School of Atmospheric Sciences, Sun Yat-sen University, China
| | - Hairong Cheng
- Department of Environmental Engineering, School of Resource and Environmental Sciences, Wuhan University, China
| | - Yangzong Zeren
- Air Quality Studies, Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong
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20
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Zhang Y, Yang W, Simpson I, Huang X, Yu J, Huang Z, Wang Z, Zhang Z, Liu D, Huang Z, Wang Y, Pei C, Shao M, Blake DR, Zheng J, Huang Z, Wang X. Decadal changes in emissions of volatile organic compounds (VOCs) from on-road vehicles with intensified automobile pollution control: Case study in a busy urban tunnel in south China. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 233:806-819. [PMID: 29144986 DOI: 10.1016/j.envpol.2017.10.133] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 10/23/2017] [Accepted: 10/28/2017] [Indexed: 06/07/2023]
Abstract
In the efforts at controlling automobile emissions, it is important to know in what extent air pollutants from on-road vehicles could be truly reduced. In 2014 we conducted tests in a heavily trafficked tunnel in south China to characterize emissions of volatile organic compounds (VOC) from on-road vehicle fleet and compared our results with those obtained in the same tunnel in 2004. Alkanes, aromatics, and alkenes had average emission factors (EFs) of 338, 63, and 42 mg km-1 in 2014 against that of 194, 129, and 160 mg km-1 in 2004, respectively. In 2014, LPG-related propane, n-butane and i-butane were the top three non-methane hydrocarbons (NMHCs) with EFs of 184 ± 21, 53 ± 6 and 31 ± 3 mg km-1; the gasoline evaporation marker i-pentane had an average EF of 17 ± 3 mg km-1; ethylene and propene were the top two alkenes with average EFs of 16 ± 1 and 9.7 ± 0.9 mg km-1, respectively; isoprene had no direct emission from vehicles; toluene showed the highest EF of 11 ± 2 mg km-1 among the aromatics; and acetylene had an average EF of 7 ± 1 mg km-1. While EFs of total NMHCs decreased only 9% from 493 ± 120 mg km-1 in 2004 to 449 ± 40 mg km-1 in 2014, their total ozone formation potential (OFP) decreased by 57% from 2.50 × 103 mg km-1 in 2004 to 1.10 × 103 mg km-1 in 2014, and their total secondary organic aerosol formation potential (SOAFP) decreased by 50% from 50 mg km-1 in 2004 to 25 mg km-1 in 2014. The large drop in ozone and SOA formation potentials could be explained by reduced emissions of reactive alkenes and aromatics, due largely to fuel transition from gasoline/diesel to LPG for taxis/buses and upgraded vehicle emission standards.
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Affiliation(s)
- Yanli Zhang
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Weiqiang Yang
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Isobel Simpson
- Department of Chemistry, University of California, Irvine, CA, USA
| | - Xinyu Huang
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jianzhen Yu
- Department of Chemistry, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Zhonghui Huang
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhaoyi Wang
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhou Zhang
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Di Liu
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Zuzhao Huang
- Guangzhou Environmental Monitoring Center, Guangzhou 510030, China
| | - Yujun Wang
- Guangzhou Environmental Monitoring Center, Guangzhou 510030, China
| | - Chenglei Pei
- Guangzhou Environmental Monitoring Center, Guangzhou 510030, China
| | - Min Shao
- State Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Institute for Environmental and Climate Research, Jinan University, Guangzhou 511443, China
| | - Donald R Blake
- Department of Chemistry, University of California, Irvine, CA, USA
| | - Junyu Zheng
- Institute for Environmental and Climate Research, Jinan University, Guangzhou 511443, China
| | - Zhijiong Huang
- Institute for Environmental and Climate Research, Jinan University, Guangzhou 511443, China
| | - Xinming Wang
- State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
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Deng W, Hu Q, Liu T, Wang X, Zhang Y, Song W, Sun Y, Bi X, Yu J, Yang W, Huang X, Zhang Z, Huang Z, He Q, Mellouki A, George C. Primary particulate emissions and secondary organic aerosol (SOA) formation from idling diesel vehicle exhaust in China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 593-594:462-469. [PMID: 28355592 DOI: 10.1016/j.scitotenv.2017.03.088] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 03/08/2017] [Accepted: 03/09/2017] [Indexed: 05/16/2023]
Abstract
In China diesel vehicles dominate the primary emission of particulate matters from on-road vehicles, and they might also contribute substantially to the formation of secondary organic aerosols (SOA). In this study tailpipe exhaust of three typical in-use diesel vehicles under warm idling conditions was introduced directly into an indoor smog chamber with a 30m3 Teflon reactor to characterize primary emissions and SOA formation during photo-oxidation. The emission factors of primary organic aerosol (POA) and black carbon (BC) for the three types of Chinese diesel vehicles ranged 0.18-0.91 and 0.15-0.51gkg-fuel-1, respectively; and the SOA production factors ranged 0.50-1.8gkg-fuel-1 and SOA/POA ratios ranged 0.7-3.7 with an average of 2.2. The fuel-based POA emission factors and SOA production factors from this study for idling diesel vehicle exhaust were 1-3 orders of magnitude higher than those reported in previous studies for idling gasoline vehicle exhaust. The emission factors for total particle numbers were 0.65-4.0×1015particleskg-fuel-1, and particles with diameters less than 50nm dominated in total particle numbers. Traditional C2-C12 precursor non-methane hydrocarbons (NMHCs) could only explain less than 3% of the SOA formed during aging and contribution from other precursors including intermediate volatile organic compounds (IVOC) needs further investigation.
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Affiliation(s)
- Wei Deng
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qihou Hu
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Tengyu Liu
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Xinming Wang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
| | - Yanli Zhang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Wei Song
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Yele Sun
- Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
| | - Xinhui Bi
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Jianzhen Yu
- Division of Environment, Hong Kong University of Science & Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Weiqiang Yang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xinyu Huang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhou Zhang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Zhonghui Huang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Quanfu He
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Abdelwahid Mellouki
- Institut de Combustion, Aérothermique, Réactivité et Environnement (ICARE), CNRS, 45071 Orléans Cedex 02, France
| | - Christian George
- Institut de Recherches sur la Catalyse et l'Environnement de Lyon (IRCELYON), CNRS, UMR5256, Villeurbanne F-69626, France
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Wang T, Xue L, Brimblecombe P, Lam YF, Li L, Zhang L. Ozone pollution in China: A review of concentrations, meteorological influences, chemical precursors, and effects. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 575:1582-1596. [PMID: 27789078 DOI: 10.1016/j.scitotenv.2016.10.081] [Citation(s) in RCA: 469] [Impact Index Per Article: 67.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 10/06/2016] [Accepted: 10/11/2016] [Indexed: 05/22/2023]
Abstract
High concentrations of ozone in urban and industrial regions worldwide have long been a major air quality issue. With the rapid increase in fossil fuel consumption in China over the past three decades, the emission of chemical precursors to ozone-nitrogen oxides and volatile organic compounds-has increased sharply, surpassing that of North America and Europe and raising concerns about worsening ozone pollution in China. Historically, research and control have prioritized acid rain, particulate matter, and more recently fine particulate matter (PM2.5). In contrast, less is known about ozone pollution, partly due to a lack of monitoring of atmospheric ozone and its precursors until recently. This review summarizes the main findings from published papers on the characteristics and sources and processes of ozone and ozone precursors in the boundary layer of urban and rural areas of China, including concentration levels, seasonal variation, meteorology conducive to photochemistry and pollution transport, key production and loss processes, ozone dependence on nitrogen oxides and volatile organic compounds, and the effects of ozone on crops and human health. Ozone concentrations exceeding the ambient air quality standard by 100-200% have been observed in China's major urban centers such as Jing-Jin-Ji, the Yangtze River delta, and the Pearl River delta, and limited studies suggest harmful effect of ozone on human health and agricultural corps; key chemical precursors and meteorological conditions conductive to ozone pollution have been investigated, and inter-city/region transport of ozone is significant. Several recommendations are given for future research and policy development on ground-level ozone.
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Affiliation(s)
- Tao Wang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong.
| | - Likun Xue
- Environment Research Institute, Shandong University, Ji'nan, Shandong, China
| | - Peter Brimblecombe
- School of Energy and Environment, City University of Hong Kong, Hong Kong
| | - Yun Fat Lam
- School of Energy and Environment, City University of Hong Kong, Hong Kong
| | - Li Li
- Shanghai Academy of Environmental Sciences, Shanghai, China
| | - Li Zhang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong
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Huang Z, Zhang Y, Yan Q, Zhang Z, Wang X. Real-time monitoring of respiratory absorption factors of volatile organic compounds in ambient air by proton transfer reaction time-of-flight mass spectrometry. JOURNAL OF HAZARDOUS MATERIALS 2016; 320:547-555. [PMID: 27597155 DOI: 10.1016/j.jhazmat.2016.08.064] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 08/25/2016] [Accepted: 08/26/2016] [Indexed: 06/06/2023]
Abstract
Respiratory absorption factors (AFs) are essential parameters in the evaluation of human health risks from toxic volatile organic compounds (VOCs) in ambient air. A method for the real time monitoring of VOCs in inhaled and exhaled air by proton transfer reaction time-of-flight mass spectrometry (PTR-TOF-MS) has been developed to permit the calculation of respiratory AFs of VOCs. Isoprene was found to be a better breath tracer than O2, CO2, humidity, or acetone for distinguishing between the expiratory and inspiratory phases, and a homemade online breath sampling device with a buffer tube was used to optimize signal peak shapes. Preliminary tests with seven subjects exposed to aromatic hydrocarbons in an indoor environment revealed mean respiratory AFs of 55.0%, 55.9%, and 66.9% for benzene, toluene, and C8-aromatics (ethylbenzene and xylenes), respectively. These AFs were lower than the values of 90% or 100% used in previous studies when assessing the health risks of inhalation exposure to hazardous VOCs. The mean respiratory AFs of benzene, toluene and C8-aromatics were 66.5%, 70.2% and 82.3% for the three female subjects; they were noticeably much higher than that of 46.4%, 45.2% and 55.3%, respectively, for the four male subjects.
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Affiliation(s)
- Zhonghui Huang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanli Zhang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Center for Excellence in Urban Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Qiong Yan
- Department of Respiratory Diseases, Guangzhou No. 12 Peoples Hospital, Guangzhou 510620, China
| | - Zhou Zhang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Xinming Wang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Center for Excellence in Urban Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
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24
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Jin L, Luo X, Fu P, Li X. Airborne particulate matter pollution in urban China: a chemical mixture perspective from sources to impacts. Natl Sci Rev 2016. [DOI: 10.1093/nsr/nww079] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
AbstractRapid urban and industrial development has resulted in severe air-pollution problems in developing countries such as China, especially in highly industrialized and populous urban clusters. Dissecting the complex mixtures of airborne particulate matter (PM) has been a key scientific focus in the last two decades, leading to significant advances in understanding physicochemical compositions for comprehensive source apportionment. However, identifying causative components with an attributable link to population-based health outcomes remains a huge challenge. The microbiome, an integral dimension of the PM mixture, is an unexplored frontier in terms of identities and functions in atmospheric processes and human health. In this review, we identify the major gaps in addressing these issues, and recommend a holistic framework for evaluating the sources, processes and impacts of atmospheric PM pollution. Such an approach and the knowledge generated will facilitate the formulation of regulatory measures to control PM pollution in China and elsewhere.
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Affiliation(s)
- Ling Jin
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - Xiaosan Luo
- International Center for Ecology, Meteorology, and Environment, School of Applied Meteorology, Nanjing University of Information Science & Technology, Nanjing 210044, China
| | - Pingqing Fu
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
| | - Xiangdong Li
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong, China
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Fu X, Wang X, Hu Q, Li G, Ding X, Zhang Y, He Q, Liu T, Zhang Z, Yu Q, Shen R, Bi X. Changes in visibility with PM2.5 composition and relative humidity at a background site in the Pearl River Delta region. J Environ Sci (China) 2016; 40:10-19. [PMID: 26969540 DOI: 10.1016/j.jes.2015.12.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2015] [Revised: 08/08/2015] [Accepted: 08/18/2015] [Indexed: 06/05/2023]
Abstract
In fall-winter, 2007-2013, visibility and light scattering coefficients (bsp) were measured along with PM2.5 mass concentrations and chemical compositions at a background site in the Pearl River Delta (PRD) region. The daily average visibility increased significantly (p<0.01) at a rate of 1.1 km/year, yet its median stabilized at ~13 km. No haze days occurred when the 24-hr mean PM2.5 mass concentration was below 75 μg/m(3). By multiple linear regression on the chemical budget of particle scattering coefficient (bsp), we obtained site-specific mass scattering efficiency (MSE) values of 6.5 ± 0.2, 2.6 ± 0.3, 2.4 ± 0.7 and 7.3 ± 1.2m(2)/g, respectively, for organic matter (OM), ammonium sulfate (AS), ammonium nitrate (AN) and sea salt (SS). The reconstructed light extinction coefficient (bext) based on the Interagency Monitoring of Protected Visual Environments (IMPROVE) algorithm with our site-specific MSE revealed that OM, AS, AN, SS and light-absorbing carbon (LAC) on average contributed 45.9% ± 1.6%, 25.6% ± 1.2%, 12.0% ± 0.7%, 11.2% ± 0.9% and 5.4% ± 0.3% to light extinction, respectively. Averaged bext displayed a significant reduction rate of 14.1/Mm·year (p<0.05); this rate would be 82% higher if it were not counteracted by increasing relative humidity (RH) and hygroscopic growth factor (f(RH)) at rates of 2.5% and 0.16/year(-1) (p<0.01), respectively, during the fall-winter, 2007-2013. This growth of RH and f(RH) partly offsets the positive effects of lowered AS in improving visibility, and aggravated the negative effects of increasing AN to impair visibility.
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Affiliation(s)
- Xiaoxin Fu
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xinming Wang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong Key Laboratory of Environmental Resources Utilization and Protection, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
| | - Qihou Hu
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Guanghui Li
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiang Ding
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Yanli Zhang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Quanfu He
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tengyu Liu
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhou Zhang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qingqing Yu
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ruqing Shen
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xinhui Bi
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
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Zhang Z, Wang X, Zhang Y, Lü S, Huang Z, Huang X, Wang Y. Ambient air benzene at background sites in China's most developed coastal regions: exposure levels, source implications and health risks. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 511:792-800. [PMID: 25618820 DOI: 10.1016/j.scitotenv.2015.01.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Revised: 12/07/2014] [Accepted: 01/02/2015] [Indexed: 05/20/2023]
Abstract
Benzene is a known human carcinogen causing leukemia, yet ambient air quality objectives for benzene are not available in China. The ambient benzene levels at four background sites in China's most developed coastal regions were measured from March 2012 to February 2013. The sites are: SYNECP, in the Northeast China Plain (NECP); YCNCP, in the North China Plain (NCP); THYRD, in the Yangtze River Delta (YRD) and DHPRD, in the Pearl River Delta (PRD). It was found that the mean annual benzene levels (578-1297 ppt) at the background sites were alarmingly higher, especially when compared to those of 60-480 pptv monitored in 28 cities in the United States. Wintertime benzene levels were significantly elevated at both sites (SYNECP and YCNCP) in northern China due to heating with coal/biofuels. Even at these background sites, the lifetime cancer risks of benzene (1.7-3.7E-05) all exceeded 1E-06 set by USEPA as acceptable for adults. At both sites in northern China, good correlations between benzene and CO or chloromethane, together with much lower toluene/benzene (T/B) ratios, suggested that benzene was largely related to coal combustion and biomass/biofuel burning. At the DHPRD site in the PRD, benzene revealed a highly significant correlation with methyl tert-butyl ether (MTBE), indicating that its source was predominantly from vehicle emissions. At the THYRD site in the YRD, higher T/B ratios and correlations between benzene and tetrachloroethylene, or MTBE, implied that benzene levels were probably affected by both traffic-related and industrial emissions.
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Affiliation(s)
- Zhou Zhang
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xinming Wang
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
| | - Yanli Zhang
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
| | - Sujun Lü
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhonghui Huang
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xinyu Huang
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuesi Wang
- Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
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Li JJ, Wu YD, Zhang YL, Zeng PY, Tu X, Xu MY, Sun GP. Emission of odorous volatile organic compounds from a municipal manure treatment plant and their removal using a biotrickling filter. ENVIRONMENTAL TECHNOLOGY 2015; 36:1050-1056. [PMID: 25300536 DOI: 10.1080/09593330.2014.974679] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Odorous volatile organic compounds (VOCs) from municipal manure treatment facilities are considered as a major nuisance issue for operators and nearby residents. In this study, up to 71 odorous VOCs were detected by gas chromatography-mass spectrometry at the manure treatment plant. These compounds can be classified into five different categories, including alkanes, olefins, aromatics, volatile organosulphur compounds and terpenes. Toluene, dimethyl disulphide, dimethyl sulphide, xylene and ethylbenzene were the five most abundant pollutants. A pilot-scale biotrickling filter (BTF) was employed to treat the complex odorous gases. Correlation analysis showed that the removal efficiency (RE) of the BTF was related with the molecular weight and chemical structure of contaminants. Higher than 85% of REs could be reached for aromatic, terpenes and most alkanes compounds after 180 days of operation. Comparatively, most olefins and partial alkanes compounds with a molecular weight lower than 70 were not removed easily. The REs of these compounds ranged from 0% to 94%, and the average removal efficiency (RE) was only about 33.3%.
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Affiliation(s)
- Jian-Jun Li
- a Guangdong Institute of Microbiology , Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China , Guangzhou 510070 , People's Republic of China
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Zhang Y, Wang X, Zhang Z, Lü S, Huang Z, Li L. Sources of C₂-C₄ alkenes, the most important ozone nonmethane hydrocarbon precursors in the Pearl River Delta region. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 502:236-245. [PMID: 25260169 DOI: 10.1016/j.scitotenv.2014.09.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 08/22/2014] [Accepted: 09/09/2014] [Indexed: 06/03/2023]
Abstract
Surface ozone is becoming an increasing concern in China's megacities such as the urban centers located in the highly industrialized and densely populated Pearl River Delta (PRD) region, where previous studies suggested that ozone production is sensitive to VOC emissions with alkenes being important precursors. However, little was known about sources of alkenes. Here we present our monitoring of ambient volatile organic compounds at four representative urban, suburban and rural sites in the PRD region during November-December 2009, which experienced frequent ozone episodes. C2-C4 alkenes, whose total mixing ratios were 11-20% of non-methane hydrocarbons (NMHCs) quantified, accounted for 38-64% of ozone formation potentials (OFPs) and 30-50% of the total hydroxyl radical (OH) reactivity by NMHCs. Ethylene was the most abundant alkene, accounting for 8-15% in total mixing ratios of NMHCs and contributed 25-46% of OFPs. Correlations between C2-C4 alkenes and typical source tracers suggested that ethylene might be largely related to vehicle exhausts and industry activities, while propene and butenes were much more LPG-related. Positive Matrix Factorization (PMF) confirmed that vehicle exhaust and liquefied petroleum gas (LPG) were two major sources that altogether accounted for 52-62%, 58-77%, 73-83%, 68-79% and 73-84% for ethylene, propene, 1-butene, trans-2-butene and cis-2-butene, respectively. Vehicle exhausts alone contributed 32-49% ethylene and 35-41% propene. Industry activities contributed 13-23% ethylene and 7-20% propene. LPG instead contributed the most to butenes (38-65%) and substantially to propene (23-36%). Extensive tests confirmed high fractions of propene and butenes in LPG then used in Guangzhou and in LPG combustion plumes; therefore, limiting alkene contents in LPG would benefit regional ozone control.
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Affiliation(s)
- Yanli Zhang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Xinming Wang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
| | - Zhou Zhang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Sujun Lü
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhonghui Huang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Longfeng Li
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; School of Chemistry and Material Sciences, Huaibei Normal University, Huaibei 235000, China
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Zhao X, Wang X, Ding X, He Q, Zhang Z, Liu T, Fu X, Gao B, Wang Y, Zhang Y, Deng X, Wu D. Compositions and sources of organic acids in fine particles (PM2.5) over the Pearl River Delta region, South China. J Environ Sci (China) 2014; 26:110-121. [PMID: 24649696 DOI: 10.1016/s1001-0742(13)60386-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Organic acids as important constituents of organic aerosols not only influence the aerosols' hygroscopic property, but also enhance the formation of new particles and secondary organic aerosols. This study reported organic acids including C14-C32 fatty acids, C4-C9 dicarboxylic acids and aromatic acids in PM2.5 collected during winter 2009 at six typical urban, suburban and rural sites in the Pearl River Delta region. Averaged concentrations of C14-C32 fatty acids, aromatic acids and C4-C9 dicarboxylic acids were 157, 72.5 and 50.7 ng/m3, respectively. They totally accounted for 1.7% of measured organic carbon. C20-C32 fatty acids mainly deriving from higher plant wax showed the highest concentration at the upwind rural site with more vegetation around, while C14-C18 fatty acids were more abundant at urban and suburban sites, and dicarboxylic acids and aromatic acids except 1,4-phthalic acid peaked at the downwind rural site. Succinic and azelaic acid were the most abundant among C4-C9 dicarboxylic acids, and 1,2-phthalic and 1,4-phthalic acid were dominant aromatic acids. Dicarboxylic acids and aromatic acids exhibited significant mutual correlations except for 1,4-phthalic acid, which was probably primarily emitted from combustion of solid wastes containing polyethylene terephthalate plastics. Spatial patterns and correlations with typical source tracers suggested that C14-C32 fatty acids were mainly primary while dicarboxylic and aromatic acids were largely secondary. Principal component analysis resolved six sources including biomass burning, natural higher plant wax, two mixed anthropogenic and two secondary sources; further multiple linear regression revealed their contributions to individual organic acids. It turned out that more than 70% of C14-C18 fatty acids were attributed to anthropogenic sources, about 50%-85% of the C20-C32 fatty acids were attributed to natural sources, 80%-95% of dicarboxylic acids and 1,2-phthalic acid were secondary in contrast with that 81% of 1,4-phthalic acid was primary.
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Zhang Y, Wang X, Barletta B, Simpson IJ, Blake DR, Fu X, Zhang Z, He Q, Liu T, Zhao X, Ding X. Source attributions of hazardous aromatic hydrocarbons in urban, suburban and rural areas in the Pearl River Delta (PRD) region. JOURNAL OF HAZARDOUS MATERIALS 2013; 250-251:403-11. [PMID: 23500420 DOI: 10.1016/j.jhazmat.2013.02.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2012] [Revised: 01/24/2013] [Accepted: 02/13/2013] [Indexed: 05/22/2023]
Abstract
Aromatic hydrocarbons (AHs) are both hazardous air pollutants and important precursors to ozone and secondary organic aerosols. Here we investigated 14 C6-C9 AHs at one urban, one suburban and two rural sites in the Pearl River Delta region during November-December 2009. The ratios of individual aromatics to acetylene were compared among these contrasting sites to indicate their difference in source contributions from solvent use and vehicle emissions. Ratios of toluene to benzene (T/B) in urban (1.8) and suburban (1.6) were near that of vehicle emissions. Higher T/B of 2.5 at the rural site downwind the industry zones reflected substantial contribution of solvent use while T/B of 0.8 at the upwind rural site reflected the impact of biomass burning. Source apportionment by positive matrix factorization (PMF) revealed that solvent use, vehicle exhaust and biomass burning altogether accounted for 89-94% of observed AHs. Vehicle exhaust was the major source for benzene with a share of 43-70% and biomass burning in particular contributed 30% to benzene in the upwind rural site; toluene, C8-aromatics and C9-aromatics, however, were mainly from solvent use, with contribution percentages of 47-59%, 52-59% and 41-64%, respectively.
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Affiliation(s)
- Yanli Zhang
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 510640, Guangzhou, China
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