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One-Year Characterization and Reactivity of Isoprene and Its Impact on Surface Ozone Formation at A Suburban Site in Guangzhou, China. ATMOSPHERE 2019. [DOI: 10.3390/atmos10040201] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Isoprene has a potentially large effect on ozone (O3) formation in the subtropical, highly polluted city of Guangzhou. Online measurements of isoprene in Guangzhou city are scarce; thus, isoprene levels were monitored for one year at the Guangzhou Panyu Atmospheric Composition Station (GPACS), a suburban site in Guangzhou, using an online gas chromatography-flame ionization detector (GC–FID) system to investigate the characterization and reactivity of isoprene and its effect on the O3 peak profile in different seasons. The results showed that the daily average mixing ratios of isoprene at GPACS were 0.40, 2.20, 1.40, and 0.13 mixing ratio by volume (ppbv) in spring, summer, autumn, and winter, respectively. These values were considerably higher than the mixing ratios of isoprene in the numerous other subtropical and temperate cities around the world. Furthermore, isoprene ranked first with regard to O3 formation potential (OFP) and propylene-equivalent mixing ratio among 56 measured non–methane hydrocarbons (NMHCs). The ratios of isoprene to cis-2-butene, an exhaust tracer, were determined to estimate the fractions of biogenic and anthropogenic emissions. The results revealed a much greater contribution from biogenic than anthropogenic factors during the daytime in all four seasons. In addition, night-time isoprene emissions were mostly associated with vehicles in winter, and the residual isoprene that remained after photochemical loss during the daytime also persisted into the night. The high levels of isoprene in summer and autumn may cause the strong and broad peaks of the O3 profile because of its association with the most favorable meteorological conditions (e.g., high temperature and intense solar radiation) and the highest OH mixing ratio, which could affect human health by exposing people to a high O3 mixing ratio for prolonged periods. The lower mixing ratios of isoprene resulted in a weak and sharp peak in the O3 profile in both spring and winter. The high level of isoprene in the subtropical zone could accentuate its large impact on atmospheric oxidant capacity and air quality in Guangzhou city.
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52
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Maji KJ, Ye WF, Arora M, Nagendra SMS. Ozone pollution in Chinese cities: Assessment of seasonal variation, health effects and economic burden. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 247:792-801. [PMID: 30721870 DOI: 10.1016/j.envpol.2019.01.049] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 01/12/2019] [Accepted: 01/12/2019] [Indexed: 05/10/2023]
Abstract
The ground-level ozone (O3) concentration in the urban regions of China has become an increasingly noticeable environmental problem in recent years. Many epidemiological studies have reported the association between O3 pollution and mortality, only a few studies have focused on the O3-related mortality and corresponding economic effects at the Chinese city and province level. This study reports the seasonal variation of ground-level O3 in 338 cities of China during the year 2016 and evaluates its effect on premature mortality and economic loss. It further illustrates the differences in cause-specific mortality outcomes of the log-linear and linear model, two of the prominently used methods for estimating health effects. In 2016, the annual average daily maximum 8-h O3 concentration in China ranged between 74 and 201 μg/m3 (138 ± 24.7 μg/m3). 30% of the total population was exposed to >160 μg/m3 O3 concentration (Chinese national ambient air quality standard) and about 67.2% urban population lived in exposure above the WHO recommended O3 concentrations (100 μg/m3). The estimated national O3-attributable mortality was 74.2 × 103 (95% CI: 16.7×103-127×103) in the log-linear model, whereas, the total O3-related mortality using the linear model was 69.6 × 103 (95% CI: 16.2 × 103-115 × 103). The exposure to O3 caused a nationwide economic loss of about 7.6 billion US$ (range: 1.7-12.9) in 2016. This study uniquely provides most comprehensive coverage of the Chinese cities for O3 associated mortality utilizing ground level measurement data for 2016 and presents a measurable assessment to the policymakers of China for streamlining their efforts on air quality improvement and O3 containment.
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Affiliation(s)
- Kamal Jyoti Maji
- Centre for Environmental Science and Engineering (CESE), Indian Institute of Technology Bombay, Mumbai, 400076, India; Department of Civil Engineering, Indian Institute of Technology Madras, Chennai, 600036, India.
| | - Wei-Feng Ye
- School of Environment & Natural Resources, Renmin University of China, Beijing, 100872, China
| | - Mohit Arora
- Engineering Product Development Pillar, Singapore University of Technology and Design, 8 Somapah Road, 487372, Singapore
| | - S M Shiva Nagendra
- Department of Civil Engineering, Indian Institute of Technology Madras, Chennai, 600036, India
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53
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Li X, Guo T, Peng Z, Xu L, Dong J, Cheng P, Zhou Z. Real-time monitoring and quantification of organic by-products and mechanism study of acetone decomposition in a dielectric barrier discharge reactor. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:6773-6781. [PMID: 30628003 DOI: 10.1007/s11356-019-04127-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 01/02/2019] [Indexed: 06/09/2023]
Abstract
Non-thermal plasma (NTP) degradation of low-concentration acetone was investigated in a cylindrical dielectric barrier discharge reactor. The effects of oxygen content and flow rate on the removal efficiency at various discharge powers were examined in real-time. The acetone removal efficiency decreases drastically and then remains stable or increases gradually as the O2 content increases from 0 to 25%, and further to 50%. The organic by-products were characterized and quantified using a real-time proton transfer reaction time-of-flight mass spectrometry (PTR-TOF-MS) instrument. The observed organic compounds, with concentrations about ppbv/ppmv by volume, were mainly formaldehyde, methanol, ketene, acetaldehyde, formic acid, acetone, and acetic acid. The discharge power was a critical factor affecting the concentration of the organic by-products and the selectivity toward CO2. The mechanism study based on the by-product monitor in real-time showed that acetone firstly fragments into methyl radicals, acetyl radicals, and H; then, the methyl and acetyl radicals are oxidized by O or OH radicals into acetaldehyde, methanol, and other compounds. It seems that acetaldehyde could be an intermediate in acetone decomposition. Firstly, most of the acetone molecules were decomposed into acetaldehyde molecules; then, the acetaldehyde molecules continued to be decomposed and oxidized into other compounds, such as acetic acid and formaldehyde. These investigations not only proposed a detail decomposition mechanism for acetone in dielectric barrier discharge reactor, but also provided a potential way to analyze and evaluate the practicability of NTP removal of VOCs.
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Affiliation(s)
- Xueshuang Li
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China
| | - Teng Guo
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China
| | - Zhen Peng
- Kunshan Hexin Mass Spectrometry Technology Co., Ltd., Kunshan, 215311, China
| | - Li Xu
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China
| | - Junguo Dong
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China
| | - Ping Cheng
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China.
| | - Zhen Zhou
- Institute of Mass Spectrometer and Atmospheric Environment, Jinan University, Guangzhou, 510632, China
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54
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Hui L, Liu X, Tan Q, Feng M, An J, Qu Y, Zhang Y, Cheng N. VOC characteristics, sources and contributions to SOA formation during haze events in Wuhan, Central China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 650:2624-2639. [PMID: 30373049 DOI: 10.1016/j.scitotenv.2018.10.029] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 09/27/2018] [Accepted: 10/02/2018] [Indexed: 06/08/2023]
Abstract
Based on detailed data on 102 volatile organic compounds (VOCs) measured continuously from 2016.10.9 to 2016.11.17 in Wuhan, the VOC characteristics, secondary organic aerosol (SOA) characteristics, SOA formation potential (SOAP), potential source regions, sources and contributions during different haze episodes were analyzed. The total VOC (TVOC) concentrations on clear days (visibility >10 km), slight haze days (visibility of 5-10 km), and severe haze days (visibility <5 km) were 34.87 ± 14.89 ppbv, 45.06 ± 26.69 ppbv, and 49.55 ± 24.82 ppbv, respectively. The SOAP on haze days (447.04 ± 253.85 ppbv) was significantly higher than that on clear days (300.62 ± 138.48 ppbv), and aromatics were the dominant contributors to SOA formation under different visibility conditions, accounting for approximately 97% of the total SOAP. The ratio of ethylbenzene to m/p-xylene (E/X) indicated that atmospheric photochemical reactions were slightly stronger on haze days. The ratio of toluene to benzene (T/B) indicated that vehicle exhaust had significant effects on VOCs, but no significant changes occurred during different haze episodes. The ratio of benzene, toluene, ethylbenzene and xylenes (BTEX) to CO indicated that VOCs from solvent usage in painting/coating and industrial emissions increased with increasing haze pollution. Based on backward trajectories and the potential source contribution function (PSCF), short-distance transport was the main source influencing VOC pollution, especially transport from the southwest. Seven sources were identified by positive matrix factorization (PMF): industrial sources, vehicular exhaust, solvent usage in painting/coating, fuel evaporation, liquefied petroleum gas (LPG) usage, biogenic sources and biomass burning. Moreover, solvent usage in painting/coating, vehicle exhaust and LPG usage were the most important sources that significantly aggravated VOC pollution during haze events. The results can provide references for local governments developing control strategies of VOCs during haze pollution events.
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Affiliation(s)
- Lirong Hui
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Xingang Liu
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China.
| | - Qinwen Tan
- Chengdu Academy of Environmental Sciences, Chengdu 610072, China
| | - Miao Feng
- Chengdu Academy of Environmental Sciences, Chengdu 610072, China
| | - Junling An
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
| | - Yu Qu
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
| | - Yuanhang Zhang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Nianliang Cheng
- Beijing Municipal Environmental Monitoring Center, Beijing 100048, China
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55
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Yao D, Lyu X, Murray F, Morawska L, Yu W, Wang J, Guo H. Continuous effectiveness of replacing catalytic converters on liquified petroleum gas-fueled vehicles in Hong Kong. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 648:830-838. [PMID: 30138883 DOI: 10.1016/j.scitotenv.2018.08.191] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 08/15/2018] [Accepted: 08/16/2018] [Indexed: 06/08/2023]
Abstract
To mitigate the concentrations of air pollutants in the atmosphere, an intervention program of replacing the converters of liquefied petroleum gas (LPG) fueled vehicles was implemented by the Hong Kong government between October 2013 and April 2014. Data of ambient volatile organic compounds (VOCs) and other trace gases continuously monitored from September 2012 to April 2017 at a roadside site were used to evaluate the continuous effectiveness of the replaced catalytic converters on the reduction of air pollutants. The measurement data showed that LPG-related VOCs (propane and n/i-butanes) and several trace gases (CO, NO and NO2) decreased significantly from before to after the program (p < 0.01). To further assess the efficiency of the program, five periods covering before the program, during the program, 1st year after the program, 2nd year after the program and 3rd year after the program were categorized. The values of propane and n/i-butanes decreased from Period-1 (before the program) to Period-2 (during the program), and from Period-2 to Periods 3-5 (after the program) (p < 0.01). In addition, the reduction rates of propane and n/i-butanes remained high and constant in Periods 3-5, suggesting that either had the vehicle owners themselves routinely replaced the converters at suitable interval afterwards, or were their vehicles caught by a remote sensing program checking excessive emissions. Source apportionment analysis indicated that LPG-fueled vehicular emissions were the top contributor to ambient VOCs in the roadside environment while the VOCs emitted from LPG-fueled vehicles indeed decreased at a rate of 4.21 ± 2.38 ppbv/year (average ± 95% confidence interval) from Period-1 to Period-5 (p < 0.01). Furthermore, the photochemical box model simulations revealed that the net negative contribution of VOCs and NOx emitted from LPG-fueled vehicles to O3 production strengthened at a rate of 1.9 × 10-2 pptv/day from Period-1 to Period-5 (p < 0.01). The findings proved the continuous effectiveness of the intervention program, and are of help to future control strategies in Hong Kong.
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Affiliation(s)
- Dawen Yao
- Air Quality Studies, Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong
| | - Xiaopu Lyu
- Air Quality Studies, Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong
| | - Frank Murray
- School of Environmental Sciences, Murdoch University, Perth, Australia
| | - Lidia Morawska
- International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane, Australia
| | - Wang Yu
- Air Quality Studies, Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong
| | - Jiaying 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.
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56
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PAN–Precursor Relationship and Process Analysis of PAN Variations in the Pearl River Delta Region. ATMOSPHERE 2018. [DOI: 10.3390/atmos9100372] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Peroxy acetyl nitrate (PAN) is an important photochemical product formed from the reactions between volatile organic compounds (VOCs) and nitrogen oxides (NOx) under sunlight. In this study, a field measurement was conducted at a rural site (the backgarden site, or BGS) of the Pearl River Delta (PRD) region in 2006, with the 10 min maximum PAN mixing ratios of 3.9 ppbv observed. The factors influencing the abundance of PAN at the BGS site was evaluated by the process analysis through the Weather Research and Forecasting-Community Multiscale Air Quality (WRF-CMAQ) model. The results suggested that the increase of PAN abundance at the BGS site was mainly controlled by the gas-phase chemistry, followed by vertical transport, while its loss was modulated mainly by dry deposition and horizontal transport. As the dominant important role of gas-phase chemistry, to provide detailed information on the photochemical formation of PAN, a photochemical box model with near-explicit chemical mechanism (i.e., the master chemical mechanism, MCM) was used to explore the relationship of photochemical PAN formation with its precursors based on the measured data at the BGS site. It was found that PAN formation was VOC-limited at the BGS site, with the oxidation of acetaldehyde the most important pathway for photochemical PAN production, followed by the oxidation and photolysis of methylglyoxal (MGLY). Among all the primary VOC precursors, isoprene and xylenes were the main contributors to PAN formation. Overall, our study provides new insights into the PAN photochemical formation and its controlling factors, and highlighted the importance of gas chemistry on the PAN abundance in the PRD region.
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57
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Zhang Y, Li R, Fu H, Zhou D, Chen J. Observation and analysis of atmospheric volatile organic compounds in a typical petrochemical area in Yangtze River Delta, China. J Environ Sci (China) 2018; 71:233-248. [PMID: 30195682 DOI: 10.1016/j.jes.2018.05.027] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 05/24/2018] [Accepted: 05/25/2018] [Indexed: 06/08/2023]
Abstract
Volatile organic compounds (VOCs) are a kind of important precursors for ozone photochemical formation. In this study, VOCs were measured from November 5th, 2013 to January 6th, 2014 at the Second Jinshan Industrial Area, Shanghai, China. The results showed that the measured VOCs were dominated by alkanes (41.8%), followed by aromatics (20.1%), alkenes (17.9%), and halo-hydrocarbons (12.5%). The daily trend of the VOC concentration showed a bimodal feature due to the rush-hour traffic in the morning and at nightfall. Based on the VOC concentration, a receptor model of Positive Matrix Factorization (PMF) coupled with the information related to VOC sources was applied to identify the major VOC emissions. The result showed five major VOC sources: solvent use and industrial processes were responsible for about 30% of the ambient VOCs, followed by rubber chemical industrial emissions (23%), refinery and petrochemical industrial emissions (21%), fuel evaporations (13%) and vehicular emissions (13%). The contribution of generalized industrial emissions was about 74% and significantly higher than that made by vehicle exhaust. Using a propylene-equivalent method, alkenes displayed the highest concentration, followed by aromatics and alkanes. Based on a maximum incremental reactivity (MIR) method, the average hourly ozone formation potential (OFP) of VOCs is 220.49 ppbv. The most significant source for ozone chemical formation was identified to be rubber chemical industrial emissions, following one by vehicular emission. The data shown herein may provide useful information to develop effective VOC pollution control strategies in industrialized area.
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Affiliation(s)
- Yunchen Zhang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China
| | - Rui Li
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China
| | - Hongbo Fu
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China; Collaborative Innovation Center of Atmospheric Environment and Equipment Technology (CICAEET), Nanjing University of Information Science and Technology, Nanjing 210044, China.
| | - Dong Zhou
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China
| | - Jianmin Chen
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China.
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58
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Deng T, Huang Y, Li Z, Wang N, Wang S, Zou Y, Yin C, Fan S. Numerical simulations for the sources apportionment and control strategies of PM 2.5 over Pearl River Delta, China, part II: Vertical distribution and emission reduction strategies. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 634:1645-1656. [PMID: 29685686 DOI: 10.1016/j.scitotenv.2018.04.209] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 04/13/2018] [Accepted: 04/16/2018] [Indexed: 05/26/2023]
Abstract
The contribution of various emission sources to the vertical structure of the PM2.5 concentration and the modeling of emission reduction strategies are emphasized in this study. Analysis of vertical distribution of PM2.5 concentration in the planetary boundary layer (PBL) reveals that strong diurnal cycle exists during the pollution episodes, with heavier surface pollution in nocturnal periods. Contributions from transportation and agriculture are mainly restricted to the surface, while contributions from industry and power are distributed in a relatively higher layer. In the northerly-controlled episodes, the contribution of local emissions mainly accumulates below 300 m and the impact of the emissions from surrounding cities can reach 500-600 m during nocturnal periods. The contributions outside of Guangdong are uniformly distributed within 1000 m altitude. In the daytime, the contribution of emissions is basically uniform throughout the PBL. In the southerly-controlled episodes, the contribution of local emission mainly concentrates below 400 m during the nocturnal periods. Emissions from surrounding cities can exert the influence below 1000 m height, and the contribution outside of Guangdong reaches even 1500 m. In the daytime, the contribution of emissions in the PBL is distributed evenly. The highest altitude of the contribution from different subdomains that can reach is closely related to the physical property of the PBL. The industrial and agricultural emissions are the most important contributors for the surface PM2.5 concentration. Results from emission reduction experiments show that PM2.5 reduces significantly near the pollution center. Although control efficiency decreases with the increasing reduction ratio, the efficiency differences between 30% and 50% reduction is limited. In particular, 10% reduction in industrial emission causes PM2.5 concentration to be slightly higher in the afternoon. Furthermore, below 200-m height, emission reduction experiments perform the effective reduction in PM2.5 concentration, and higher reduction ratio results in larger reduced PM2.5 concentration on almost all layers in the PBL.
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Affiliation(s)
- Tao Deng
- Institute of Tropical and Marine Meteorology, China Meteorological Administration, Guangzhou, China.
| | - Yeqi Huang
- School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China; Division of Environment, Hong Kong University of Science & Technology, Clear Water Bay, Hong Kong, China
| | - Zhenning Li
- School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Nan Wang
- Institute of Tropical and Marine Meteorology, China Meteorological Administration, Guangzhou, China
| | | | - Yu Zou
- Institute of Tropical and Marine Meteorology, China Meteorological Administration, Guangzhou, China
| | - Chanqin Yin
- Institute of Tropical and Marine Meteorology, China Meteorological Administration, Guangzhou, China
| | - Shaojia Fan
- School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou, Guangdong, China.
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59
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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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60
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Wang S, Du L, Zhu J, Tsona NT, Liu S, Wang Y, Ge M, Wang W. Gas-Phase Oxidation of Allyl Acetate by O 3, OH, Cl, and NO 3: Reaction Kinetics and Mechanism. J Phys Chem A 2018; 122:1600-1611. [PMID: 29388423 DOI: 10.1021/acs.jpca.7b10599] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Allyl acetate (AA) is widely used as monomer and intermediate in industrial chemicals synthesis. To evaluate the atmospheric outcome of AA, kinetics and mechanism of its gas-phase reaction with main atmospheric oxidants (O3, OH, Cl, and NO3) have been investigated in a Teflon reactor at 298 ± 3 K. Both absolute and relative rate methods were used to determine the rate constants for AA reactions with the four atmospheric oxidants. The obtained rate constants (in units of cm3 molecule-1 s-1) are (1.8 ± 0.3) × 10-18, (3.1 ± 0.7) × 10-11, (2.5 ± 0.5) × 10-10, and (1.1 ± 0.4) × 10-14, for reactions with O3, OH, Cl, and NO3, respectively. While results for reactions with O3, OH and Cl are in good agreement with previous studies, the kinetics for the reaction with NO3 is reported for the first time in this study. On the basis of determined rate constants, the tropospheric lifetimes of AA are τO3 = 9 days, τOH = 5 h, τCl = 5 days, τNO3 = 2 days. On the basis of the products study, reaction mechanisms for these oxidations have been proposed and the reaction products were detected using thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) and Fourier transform infrared spectroscopy (FTIR). Results show that the main products formed in these reactions are carbonyl compounds. In particular, 2-oxoethyl acetate was detected in all four AA oxidation reactions. Compared to previous studies, several new products were determined for reactions with OH and Cl. These results form a set of comprehensive kinetic data for AA reactions with main atmospheric oxidants and provide a better understanding of the degradation and atmospheric outcome of unsaturated acetate esters in the troposphere, during both daytime and nighttime.
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Affiliation(s)
- Shuyan Wang
- Environment Research Institute, Shandong University , Jinan 250100, China
| | - Lin Du
- Environment Research Institute, Shandong University , Jinan 250100, China
| | - Jianqiang Zhu
- Environment Research Institute, Shandong University , Jinan 250100, China
| | - Narcisse T Tsona
- Environment Research Institute, Shandong University , Jinan 250100, China
| | - Shijie Liu
- Environment Research Institute, Shandong University , Jinan 250100, China
| | - Yifeng Wang
- Key Lab of Colloid and Interface Science of the Education Ministry, Department of Chemistry and Chemical Engineering, Shandong University , Jinan 250100, China
| | - Maofa Ge
- Beijing National Laboratory for Molecular Sciences (BNLMS), State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China
| | - Wenxing Wang
- Environment Research Institute, Shandong University , Jinan 250100, China
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61
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An J, Wang J, Zhang Y, Zhu B. Source Apportionment of Volatile Organic Compounds in an Urban Environment at the Yangtze River Delta, China. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2017; 72:335-348. [PMID: 28190079 DOI: 10.1007/s00244-017-0371-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2016] [Accepted: 01/20/2017] [Indexed: 06/06/2023]
Abstract
Volatile organic compounds (VOCs) were collected continuously during June-August 2013 and December 2013-February 2014 at an urban site in Nanjing in the Yangtze River Delta. The positive matrix factorization receptor model was used to analyse the sources of VOCs in different seasons. Eight and seven sources were identified in summer and winter, respectively. In summer and winter, the dominant sources of VOCs were vehicular emissions, liquefied petroleum gas/natural gas (LPG/NG) usage, solvent usage, biomass/biofuel burning, and industrial production. In summer, vehicular emissions made the most significant contribution to ambient VOCs (38%), followed by LPG/NG usage (20%), solvent usage (19%), biomass/biofuel burning (13%), and industrial production (10%). In winter, LPG/NG usage accounted for 36% of ambient VOCs, whereas vehicular emissions, biomass/biofuel burning, industrial production and solvent usage contributed 30, 18, 9, and 6%, respectively. The contribution of LPG/NG usage in winter was approximately four times that in summer, whereas the contribution from biomass/biofuel burning in winter was more than twice that in summer. The sources related to vehicular emissions and LPG/NG usages were important. Using conditional probability function analysis, the VOC sources were mainly associated with easterly, northeasterly and southeasterly directions, pointing towards the major expressway and industrial area. Using the propylene-equivalent method, paint and varnish (23%) was the highest source of VOCs in summer and biomass/biofuel burning (36%) in winter. Using the ozone formation potential method, the most important source was biomass/biofuel burning (32% in summer and 47% in winter). The result suggests that the biomass/biofuel burning and paint and varnish play important roles in controlling ozone chemical formation in Nanjing.
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Affiliation(s)
- Junlin An
- Key Laboratory of Meteorological Disaster, Ministry of Education (KLME)/Joint International Research Laboratory of Climate and Environment Change (ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD)/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science and Technology, Nanjing, 210044, China.
| | - Junxiu Wang
- Key Laboratory of Meteorological Disaster, Ministry of Education (KLME)/Joint International Research Laboratory of Climate and Environment Change (ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD)/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science and Technology, Nanjing, 210044, China
| | - Yuxin Zhang
- Key Laboratory of Meteorological Disaster, Ministry of Education (KLME)/Joint International Research Laboratory of Climate and Environment Change (ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD)/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science and Technology, Nanjing, 210044, China
| | - Bin Zhu
- Key Laboratory of Meteorological Disaster, Ministry of Education (KLME)/Joint International Research Laboratory of Climate and Environment Change (ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD)/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science and Technology, Nanjing, 210044, China
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Chen J, Li C, Ristovski Z, Milic A, Gu Y, Islam MS, Wang S, Hao J, Zhang H, He C, Guo H, Fu H, Miljevic B, Morawska L, Thai P, Lam YF, Pereira G, Ding A, Huang X, Dumka UC. A review of biomass burning: Emissions and impacts on air quality, health and climate in China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 579:1000-1034. [PMID: 27908624 DOI: 10.1016/j.scitotenv.2016.11.025] [Citation(s) in RCA: 335] [Impact Index Per Article: 47.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 11/04/2016] [Accepted: 11/04/2016] [Indexed: 05/17/2023]
Abstract
Biomass burning (BB) is a significant air pollution source, with global, regional and local impacts on air quality, public health and climate. Worldwide an extensive range of studies has been conducted on almost all the aspects of BB, including its specific types, on quantification of emissions and on assessing its various impacts. China is one of the countries where the significance of BB has been recognized, and a lot of research efforts devoted to investigate it, however, so far no systematic reviews were conducted to synthesize the information which has been emerging. Therefore the aim of this work was to comprehensively review most of the studies published on this topic in China, including literature concerning field measurements, laboratory studies and the impacts of BB indoors and outdoors in China. In addition, this review provides insights into the role of wildfire and anthropogenic BB on air quality and health globally. Further, we attempted to provide a basis for formulation of policies and regulations by policy makers in China.
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Affiliation(s)
- Jianmin Chen
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science and Engineering, Institute of Atmospheric Sciences, Fudan University, Shanghai 200433, China; Collaborative Innovation Center of Climate Change, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China.
| | - Chunlin Li
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science and Engineering, Institute of Atmospheric Sciences, Fudan University, Shanghai 200433, China
| | - Zoran Ristovski
- International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane, QLD 4001, Australia
| | - Andelija Milic
- International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane, QLD 4001, Australia
| | - Yuantong Gu
- International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane, QLD 4001, Australia
| | - Mohammad S Islam
- International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane, QLD 4001, Australia
| | - Shuxiao Wang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Jiming Hao
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
| | - Hefeng Zhang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Congrong He
- International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane, QLD 4001, Australia
| | - Hai Guo
- Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, China
| | - Hongbo Fu
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science and Engineering, Institute of Atmospheric Sciences, Fudan University, Shanghai 200433, China
| | - Branka Miljevic
- International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane, QLD 4001, Australia
| | - Lidia Morawska
- International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane, QLD 4001, Australia.
| | - Phong Thai
- International Laboratory for Air Quality and Health, Queensland University of Technology, Brisbane, QLD 4001, Australia
| | - Yun Fat Lam
- School of Energy and Environment, City University of Hong Kong, Hong Kong, China
| | - Gavin Pereira
- School of Public Health, Curtin University, Perth, WA, 6000, Australia
| | - Aijun Ding
- Collaborative Innovation Center of Climate Change, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China
| | - Xin Huang
- Collaborative Innovation Center of Climate Change, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China
| | - Umesh C Dumka
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science and Engineering, Institute of Atmospheric Sciences, Fudan University, Shanghai 200433, China; Aryabhatta Research Institute of Observational Sciences, Manora Peak, Nainital 263001, India
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63
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Guo H, Ling ZH, Cheng HR, Simpson IJ, Lyu XP, Wang XM, Shao M, Lu HX, Ayoko G, Zhang YL, Saunders SM, Lam SHM, Wang JL, Blake DR. Tropospheric volatile organic compounds in China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 574:1021-1043. [PMID: 27668854 DOI: 10.1016/j.scitotenv.2016.09.116] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Revised: 09/13/2016] [Accepted: 09/15/2016] [Indexed: 06/06/2023]
Abstract
Photochemical smog, characterized by high concentrations of ozone (O3) and fine particles (PM2.5) in the atmosphere, has become one of the top environmental concerns in China. Volatile organic compounds (VOCs), one of the key precursors of O3 and secondary organic aerosol (SOA) (an important component of PM2.5), have a critical influence on atmospheric chemistry and subsequently affect regional and global climate. Thus, VOCs have been extensively studied in many cities and regions in China, especially in the North China Plain, the Yangtze River Delta and the Pearl River Delta regions where photochemical smog pollution has become increasingly worse over recent decades. This paper reviews the main studies conducted in China on the characteristics and sources of VOCs, their relationship with O3 and SOA, and their removal technology. This paper also provides an integrated literature review on the formulation and implementation of effective control strategies of VOCs and photochemical smog, as well as suggestions for future directions of VOCs study in China.
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Affiliation(s)
- H Guo
- Air Quality Studies, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, China.
| | - Z H Ling
- School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou, China
| | - H R Cheng
- School of Resource and Environmental Sciences, Wuhan University, Wuhan, China
| | - I J Simpson
- Department of Chemistry, University of California, Irvine, CA, USA
| | - X P Lyu
- Air Quality Studies, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, China
| | - X M Wang
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, China
| | - M Shao
- College of Environmental Sciences and Engineering, Peking University, Beijing, China
| | - H X Lu
- Air Quality Studies, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, China
| | - G Ayoko
- Discipline of Chemistry, Faculty of Science and Technology, Queensland University of Technology, Australia
| | - Y L Zhang
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, China
| | - S M Saunders
- School of Chemistry and Biochemistry, University of Western Australia, Perth, Western Australia, Australia
| | - S H M Lam
- Pacific Environment Limited, Perth, Western Australia, Australia
| | - J L Wang
- Department of Chemistry, National Central University, Taiwan
| | - D R Blake
- Department of Chemistry, University of California, Irvine, CA, USA
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Liu B, Liang D, Yang J, Dai Q, Bi X, Feng Y, Yuan J, Xiao Z, Zhang Y, Xu H. Characterization and source apportionment of volatile organic compounds based on 1-year of observational data in Tianjin, China. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2016; 218:757-769. [PMID: 27567166 DOI: 10.1016/j.envpol.2016.07.072] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 07/29/2016] [Accepted: 07/31/2016] [Indexed: 05/22/2023]
Abstract
From November 2014 to October 2015, the concentrations of volatile organic compounds (VOCs), O3 and NOx were simultaneously monitored by using online instruments at the air monitoring station belonged to Tianjin Environmental Protection Bureau (TEPB). The results indicated that VOCs concentrations were higher in autumn and lower in spring, while O3 concentrations were higher in summer, and lower in winter. The diurnal variations of VOCs and NOx (NO2 plus NO) showed opposite tendency comparing to that of O3. The concentrations of alkanes were higher (the average of 18.2 ppbv) than that of aromatics (5.3 ppbv) and alkenes (5.2 ppbv), however, the alkenes and aromatics made larger contributions to ozone because of their high reactivity. Tianjin belonged to the VOC-limited region during most of seasons (except summer) according to the VOC/NOx ratios (the 8:1 threshold). The automobile exhaust, industrial emission, liquefied petroleum gas/natural gas (LPG/NG), combustion, gasoline evaporation, internal combustion engine emission and solvent usage were identified as major sources of VOCs by Positive Matrix Factorization (PMF) model in Tianjin, and the contributions to VOCs for the entire year were 23.1%, 19.9%, 18.6%, 10.6%, 8.7%, 5.4% and 4.7%, respectively. The conditional probability function (CPF) analysis indicated that the contributing directions of automobile exhaust and industrial emission were mainly affected by source distributions, and that of other sources might be mainly affected by wind direction. The backward trajectory analysis indicated that the trajectory of air mass originated from Mongolia, which reflected the features of large-scale and long-distance air transport, and that of beginning in Jiangsu, Shandong and Tianjin, which showed the features of small-scale and short-distance. Tianjin, Beijing, Hebei and Northwest of Shandong were identified as major potential source-areas of VOCs by using potential source contribution function (PSCF) and concentration-weighted trajectory (CWT) models.
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Affiliation(s)
- Baoshuang Liu
- State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China
| | - Danni Liang
- State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China
| | - Jiamei Yang
- State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China
| | - Qili Dai
- State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China
| | - Xiaohui Bi
- State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China.
| | - Yinchang Feng
- State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China
| | - Jie Yuan
- Tianjin Environmental Monitoring Center, Tianjin, 300191, China
| | - Zhimei Xiao
- Tianjin Environmental Monitoring Center, Tianjin, 300191, China
| | - Yufen Zhang
- State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China
| | - Hong Xu
- Tianjin Environmental Monitoring Center, Tianjin, 300191, China
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Lyu XP, Liu M, Guo H, Ling ZH, Wang Y, Louie PKK, Luk CWY. Spatiotemporal variation of ozone precursors and ozone formation in Hong Kong: Grid field measurement and modelling study. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 569-570:1341-1349. [PMID: 27387808 DOI: 10.1016/j.scitotenv.2016.06.214] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 06/26/2016] [Accepted: 06/27/2016] [Indexed: 06/06/2023]
Abstract
Grid field measurements of volatile organic compounds (VOCs) covering the entire territory of Hong Kong were simultaneously carried out twice daily on 27 September 2013 and 24 September 2014, respectively, to advance our understanding on the spatiotemporal variations of VOCs and ozone (O3) formation, the factors controlling O3 formation and the efficacy of a control measure in Hong Kong. From before to after the control measure on liquefied petroleum gas (LPG) fueled vehicles, the VOCs originated from LPG vehicle exhaust deceased from 41.3±1.2μg/m(3) (49.7±1.5%) to 32.8±1.4μg/m(3) (38.8±1.7%) (p<0.05). In contrast, the contribution to VOCs made by gasoline and diesel vehicle exhaust and solvent usage increased (p<0.05). VOCs and nitric oxide (NO) in LPG source experienced the highest reductions at the roadside sites, while the variations were not significant at the urban and new town sites (p>0.05). For O3 production, LPG vehicle exhaust generally made a negative contribution (-0.17±0.06 ppbv) at the roadside sites, however it turned to a slightly positive contribution (0.004±0.038 ppbv) after the control measure. At the urban sites, although the reductions of VOCs and NO were minor (p>0.05), O3 produced by LPG vehicle significantly reduced from 4.19±1.92 ppbv to 0.95±0.38 ppbv (p<0.05). Meanwhile, O3 produced by LPG at the new town sites remained stable. The analysis of O3-precursor relationships revealed that alkenes and aromatics were the main species limiting roadside O3 formation, while aromatics were the most predominant controlling factor at urban and new town sites. In contrast, isoprene and sometimes NOx limited the O3 formation in rural environment.
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Affiliation(s)
- X P Lyu
- Air Quality Studies, Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong
| | - M Liu
- Air Quality Studies, Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong
| | - H Guo
- Air Quality Studies, Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong.
| | - Z H Ling
- Air Quality Studies, Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong
| | - Y Wang
- Air Quality Studies, Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong
| | - P K K Louie
- Air Group, Hong Kong Environmental Protection Department, Hong Kong
| | - C W Y Luk
- Air Group, Hong Kong Environmental Protection Department, Hong Kong
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66
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Wu F, Yu Y, Sun J, Zhang J, Wang J, Tang G, Wang Y. Characteristics, source apportionment and reactivity of ambient volatile organic compounds at Dinghu Mountain in Guangdong Province, China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 548-549:347-359. [PMID: 26803733 DOI: 10.1016/j.scitotenv.2015.11.069] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Revised: 09/24/2015] [Accepted: 11/13/2015] [Indexed: 05/03/2023]
Abstract
Volatile organic compounds (VOCs) play a very important role in the formation of ozone and secondary organic aerosols. The concentrations, compositions, and variability of VOCs were measured from 2005 to 2008 at Dinghu Mountain Forest Ecosystem Research Station, a remote station in Southeast China. Weekly samples were collected in the Dinghu Mountain area and were analysed via gas chromatography-mass spectrometry. The results revealed that the total VOC concentrations decreased continuously and that the dominant VOC components were alkanes (43%) and aromatics (33%), followed by halo-hydrocarbons (12%) and alkenes (12%). The general trend of seasonal variation indicated higher concentrations in spring and lower concentrations in summer. The positive matrix factorization model was used to identify the sources of the VOCs. Seven sources were resolved by the PMF model: (1) vehicular emissions, which contributed 25% of the total VOC concentration; (2) industrial sources and regional transportation, contributing 17%; (3) paint solvent use, contributing 17%; (4) fuel evaporation, contributing 13%; (5) stationary combustion sources, contributing 12%; (6) biogenic emissions, contributing 10%; and aged VOCs, contributing only 6%. The HYSPLIT model was used to analyse the effect of pollutant transport, and the results indicated that the transport of pollutants from cities cannot be ignored. Finally, the OH radical loss rates and ozone formation potentials (OFPs) were calculated, and the results indicated isoprene to have the highest OH radical loss rate and toluene to be the largest contributor to the OFP at the Dinghu Mountain site.
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Affiliation(s)
- Fangkun Wu
- Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China; Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ye Yu
- Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Jie Sun
- Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
| | - Junke Zhang
- Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
| | - Jian Wang
- Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
| | - Guiqian Tang
- Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China.
| | - Yuesi Wang
- Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China
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67
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Lyu XP, Chen N, Guo H, Zhang WH, Wang N, Wang Y, Liu M. Ambient volatile organic compounds and their effect on ozone production in Wuhan, central China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 541:200-209. [PMID: 26410695 DOI: 10.1016/j.scitotenv.2015.09.093] [Citation(s) in RCA: 103] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 08/29/2015] [Accepted: 09/17/2015] [Indexed: 06/05/2023]
Abstract
Ambient volatile organic compounds (VOCs) were continuously measured from February 2013 to October 2014 at an urban site in Wuhan. The characteristics and sources of VOCs and their effect on ozone (O3) formation were studied for the first time. The total VOC levels in Wuhan were relatively low, and of all VOCs, ethane (5.2 ± 0.2 ppbv) was the species with the highest levels. Six sources, i.e., vehicular exhausts, coal burning, liquefied petroleum gas (LPG) usage, the petrochemical industry, solvent usage in dry cleaning/degreasing, and solvent usage in coating/paints were identified, and their contributions to the total VOCs were 27.8 ± 0.9%, 21.8 ± 0.8%, 19.8 ± 0.9%, 14.4 ± 0.9%, 8.5 ± 0.5%, and 7.7 ± 0.4%, respectively. Model simulation of a photochemical box model incorporating the Master Chemical Mechanism (PBM-MCM) indicated that the contribution to O3 formation of the above sources was 23.4 ± 1.3%, 22.2 ± 1.2%, 23.1 ± 1.7%, 11.8 ± 0.9%, 5.2 ± 0.4%, and 14.2 ± 1.1%, respectively. LPG and solvent usage in coating/paints were the sources that showed higher contributions to O3 formation, compared to their contributions to VOCs. The relative incremental reactivity (RIR) analysis revealed that the O3 formation in Wuhan was generally VOC-limited, and ethene and toluene were the primary species contributing to O3 production, accounting for 34.3% and 31.5% of the total RIR-weighted concentration, respectively. In addition, the contribution of CO to the O3 formation was remarkable. The C4 alkanes and alkenes from the LPG usage also significantly contributed to the O3 formation. The results can assist local governments in formulating and implementing control strategies for photochemical pollution.
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Affiliation(s)
- X P Lyu
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong
| | - N Chen
- Hubei Provincial Environment Monitoring Center, Wuhan, China
| | - H Guo
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong.
| | - W H Zhang
- Department of Environmental Sciences, School of Resource and Environmental Sciences, Wuhan University, Wuhan, China.
| | - N Wang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong
| | - Y Wang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong
| | - M Liu
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong
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68
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Liao HT, Chou CCK, Chow JC, Watson JG, Hopke PK, Wu CF. Source and risk apportionment of selected VOCs and PM₂.₅ species using partially constrained receptor models with multiple time resolution data. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2015; 205:121-130. [PMID: 26057474 DOI: 10.1016/j.envpol.2015.05.035] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 05/22/2015] [Accepted: 05/26/2015] [Indexed: 06/04/2023]
Abstract
This study was conducted to identify and quantify the sources of selected volatile organic compounds (VOCs) and fine particulate matter (PM2.5) by using a partially constrained source apportionment model suitable for multiple time resolution data. Hourly VOC, 12-h and 24-h PM2.5 speciation data were collected during three seasons in 2013. Eight factors were retrieved from the Positive Matrix Factorization solutions and adding source profile constraints enhanced the interpretability of source profiles. Results showed that the evaporative emission factor was the largest contributor (25%) to VOC mass concentration, while the largest contributor to PM2.5 mass concentration was soil dust/regional transport related factor (26%). In terms of risk prioritization, traffic/industry related factor was the major cause for benzene, ethylbenzene, Cr, and polycyclic aromatic hydrocarbons (29-69%) while petrochemical related factor contributed most to the Ni risk (36%). This indicated that a larger contributor to mass concentration may not correspond to a higher risk.
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Affiliation(s)
- Ho-Tang Liao
- Institute of Occupational Medicine and Industrial Hygiene, National Taiwan University, Taipei, Taiwan
| | - Charles C-K Chou
- Research Center for Environmental Changes, Academia Sinica, Taipei, Taiwan
| | - Judith C Chow
- Division of Atmospheric Sciences, Desert Research Institute, Reno, NV, USA
| | - John G Watson
- Division of Atmospheric Sciences, Desert Research Institute, Reno, NV, USA
| | - Philip K Hopke
- Center for Air Resources Engineering and Science and Department of Chemical and Biomolecular Engineering, Clarkson University, Potsdam, NY, USA
| | - Chang-Fu Wu
- Institute of Occupational Medicine and Industrial Hygiene, National Taiwan University, Taipei, Taiwan; Department of Public Health, National Taiwan University, Taipei, Taiwan; Institute of Environmental Health, National Taiwan University, Taipei, Taiwan.
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69
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Cheung K, Ling ZH, Wang DW, Wang Y, Guo H, Lee B, Li YJ, Chan CK. Characterization and source identification of sub-micron particles at the HKUST Supersite in Hong Kong. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 527-528:287-296. [PMID: 25965042 DOI: 10.1016/j.scitotenv.2015.04.087] [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] [Received: 03/01/2015] [Revised: 04/16/2015] [Accepted: 04/23/2015] [Indexed: 06/04/2023]
Abstract
Particle size distribution measurements were conducted continuously at a 30-second interval using the Fast Mobility Particle Sizer (FMPS) in August, September, November and December of 2011 at a coastal background site in Hong Kong. Concurrent measurements of CO, NOx, O3, SO2 and volatile organic compounds (VOCs) were used to determine the causes of high particle number concentration (PNC) events. In all sampling months, PNC were usually higher in the evening, likely resulting from the arrival of upwind air pollutants as wind direction changed in the late afternoon. On the more polluted days, the PNC were usually higher around noon, particularly in August, similar to the diurnal trend of O3. The mode diameter at noon was smaller than in other time periods in all sampling months, further highlighting the role of secondary formation at this urban background site. A prolonged period of pollution episode occurred in late August. High PNC resulted from the arrival of pollution laden air from the PRD region or super regions. In December, new particle formation followed by subsequent growth accounted for most of the polluted days. Overall, meteorology was the most important parameter affecting particle concentrations and formation at this Hong Kong background site.
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Affiliation(s)
- K Cheung
- Air Quality Studies, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, China
| | - Z H Ling
- Air Quality Studies, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, China; Department of Atmospheric Sciences, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou, China
| | - D W Wang
- Air Quality Studies, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, China
| | - Y Wang
- Air Quality Studies, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, China
| | - H Guo
- Air Quality Studies, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, China.
| | - B Lee
- Division of Environment, Hong Kong University of Science and Technology, Hong Kong, China
| | - Y J Li
- Division of Environment, Hong Kong University of Science and Technology, Hong Kong, China
| | - C K Chan
- Division of Environment, Hong Kong University of Science and Technology, Hong Kong, China; Department of Chemical and Biomolecular Engineering, Hong Kong University of Science and Technology, Hong Kong, China.
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Yang X, Liu H, Cui H, Man H, Fu M, Hao J, He K. Vehicular volatile organic compounds losses due to refueling and diurnal process in China: 2010-2050. J Environ Sci (China) 2015; 33:88-96. [PMID: 26141881 DOI: 10.1016/j.jes.2015.01.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Revised: 01/05/2015] [Accepted: 01/19/2015] [Indexed: 06/04/2023]
Abstract
Volatile organic compounds (VOCs) are crucial to control air pollution in major Chinese cities since VOCs are the dominant factor influencing ambient ozone level, and also an important precursor of secondary organic aerosols. Vehicular evaporative emissions have become a major and growing source of VOC emissions in China. This study consists of lab tests, technology evaluation, emissions modeling, policy projections and cost-benefit analysis to draw a roadmap for China for controlling vehicular evaporative emissions. The analysis suggests that evaporative VOC emissions from China's light-duty gasoline vehicles were approximately 185,000 ton in 2010 and would peak at 1,200,000 ton in 2040 without control. The current control strategy implemented in China, as shown in business as usual (BAU) scenario, will barely reduce the long-term growth in emissions. Even if Stage II gasoline station vapor control policies were extended national wide (BAU+extended Stage II), there would still be over 400,000 ton fuel loss in 2050. In contrast, the implementation of on-board refueling vapor recovery (ORVR) on new cars could reduce 97.5% of evaporative VOCs by 2050 (BAU+ORVR/BAU+delayed ORVR). According to the results, a combined Stage II and ORVR program is a comprehensive solution that provides both short-term and long-term benefits. The net cost to achieve the optimal total evaporative VOC control is approximately 62 billion CNY in 2025 and 149 billion CNY in 2050.
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Affiliation(s)
- Xiaofan Yang
- School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, 100084, China.
| | - Huan Liu
- School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China; Collaborative Innovation Center for Regional Environmental Quality, China.
| | - Hongyang Cui
- School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, 100084, China
| | - Hanyang Man
- School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, 100084, China
| | - Mingliang Fu
- School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, 100084, China
| | - Jiming Hao
- School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China; Collaborative Innovation Center for Regional Environmental Quality, China
| | - Kebin He
- School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China; Collaborative Innovation Center for Regional Environmental Quality, China
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71
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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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72
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Ling ZH, Guo H, Zheng JY, Louie PKK, Cheng HR, Jiang F, Cheung K, Wong LC, Feng XQ. Establishing a conceptual model for photochemical ozone pollution in subtropical Hong Kong. ATMOSPHERIC ENVIRONMENT (OXFORD, ENGLAND : 1994) 2013; 76:208-220. [PMID: 32362762 PMCID: PMC7185748 DOI: 10.1016/j.atmosenv.2012.09.051] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Revised: 09/13/2012] [Accepted: 09/17/2012] [Indexed: 05/24/2023]
Abstract
Photochemical ozone (O3) formation is related to its precursors and meteorological conditions. A conceptual model of O3 air pollution is developed based on the analysis of data obtained at Tung Chung (TC) in Hong Kong. By comparing meteorological parameters between O3 and non-O3 episode days, it was found that high temperatures, strong solar radiation, low wind speeds and relative humidity, northeasterly and/or northwesterly prevailing winds were favorable for the O3 formation, while tropical cyclones were most conducive to the occurrence of O3 episodes. Backward trajectories simulation and graphical illustration of O3 pollution suggested that super-regional (i.e. central and eastern China) and regional (i.e. Pearl River Delta, southern China) transport was another factor that contributed to high O3 levels in Hong Kong. The photochemical O3 formation, generally VOC-limited in Hong Kong, was controlled by a small number of volatile organic compounds (VOCs). Furthermore, the positive matrix factorization (PMF) simulation suggested that solvent usage and vehicular emissions are the major contributors to ambient VOCs in Hong Kong. Finally, this paper presents recommendations for further O3 research and implementation of O3 control strategies.
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Affiliation(s)
- Z H Ling
- Air Quality Studies, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong
| | - H Guo
- Air Quality Studies, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong
| | - J Y Zheng
- College of Environmental Science and Engineering, South China University of Technology, B4-514, University Town, Guangzhou, PR China
| | - P K K Louie
- Air Science Group, Environmental Protection Department, Hong Kong
| | - H R Cheng
- Environmental Engineering, School of Resource and Environmental Science, Wuhan University, Hubei, China
| | - F Jiang
- International Institute for Earth System Science, Nanjing University, Nanjing, China
| | - K Cheung
- Air Quality Studies, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong
| | - L C Wong
- Air Quality Studies, Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong
| | - X Q Feng
- College of Environmental Science and Engineering, South China University of Technology, B4-514, University Town, Guangzhou, PR China
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73
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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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Ling ZH, Guo H, Cheng HR, Yu YF. Sources of ambient volatile organic compounds and their contributions to photochemical ozone formation at a site in the Pearl River Delta, southern China. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2011; 159:2310-9. [PMID: 21616570 DOI: 10.1016/j.envpol.2011.05.001] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Revised: 04/13/2011] [Accepted: 05/01/2011] [Indexed: 05/16/2023]
Abstract
The Positive Matrix Factorization (PMF) receptor model and the Observation Based Model (OBM) were combined to analyze volatile organic compound (VOC) data collected at a suburban site (WQS) in the PRD region. The purposes are to estimate the VOC source apportionment and investigate the contributions of these sources and species of these sources to the O(3) formation in PRD. Ten VOC sources were identified. We further applied the PMF-extracted concentrations of these 10 sources into the OBM and found "solvent usage 1", "diesel vehicular emissions" and "biomass/biofuel burning" contributed most to the O(3) formation at WQS. Among these three sources, higher Relative Incremental Reactivity (RIR)-weighted values of ethene, toluene and m/p-xylene indicated that they were mainly responsible for local O(3) formation in the region. Sensitivity analysis revealed that the sources of "diesel vehicular emissions", "biomass/biofuel burning" and "solvent usage 1" had low uncertainties whereas "gasoline evaporation" showed the highest uncertainty.
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Affiliation(s)
- Z H Ling
- Air Quality Studies, Department of Civil and Structural Engineering, The Hong Kong Polytechnic University, Hong Kong
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