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Askari A, Chan AWH. Organic Emissions of Volatile Chemical Products in Canada: Emission Inventories, Indoor-to-Outdoor Transfer, and Regional Impacts. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024. [PMID: 38869056 DOI: 10.1021/acs.est.3c10753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2024]
Abstract
The contribution of volatile chemical products (VCPs) to ambient air pollution has increased following decades of regulating combustion sources. There is a research gap concerning the impact of indoor physicochemical phenomena on VCP emissions. In this work, a bottom-up speciated VCP emission inventory with indoor-outdoor resolution was developed for Canada, an industrialized country with low air pollution levels, whose major cities are among the largest urban areas in North America. VCPs were estimated to account for about 290 kilotons of gaseous organic emissions for a typical year in the 2010s, with more than 60% of emissions occurring indoors. Coatings and cleaners were the most emissive VCP categories. Oxygenated species and saturated aliphatics dominated the chemical profiles of most emissions. Less than 5% of VCP emissions were impacted by indoor physicochemical phenomena. VCP emissions were predicted to account for 0.8-3.2 s-1 of OH reactivity and 0.22-0.52 μg/m3 of secondary organic aerosol formation potential in major urban areas in Canada. Our predictions aligned with previous measurements concerning indoor and outdoor organic pollutant levels, underscoring the important air quality impacts of VCPs relative to other sources. Our results provide helpful insights for future research regarding VCP emissions, especially from indoor spaces.
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Affiliation(s)
- Amirashkan Askari
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto M5S 3E5, Canada
| | - Arthur W H Chan
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto M5S 3E5, Canada
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2
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Zhou L, Liang Z, Qin Y, Chan CK. Evaporation-Induced Transformations in Volatile Chemical Product-Derived Secondary Organic Aerosols: Browning Effects and Alterations in Oxidative Reactivity. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024. [PMID: 38866390 DOI: 10.1021/acs.est.4c02316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2024]
Abstract
Volatile chemical products (VCPs) are increasingly recognized as significant sources of volatile organic compounds (VOCs) in urban atmospheres, potentially serving as key precursors for secondary organic aerosol (SOA) formation. This study investigates the formation and physicochemical transformations of VCP-derived SOA, produced through ozonolysis of VOCs evaporated from a representative room deodorant air freshener, focusing on the effects of aerosol evaporation on its molecular composition, light absorption properties, and reactive oxygen species (ROS) generation. Following aerosol evaporation, solutes become concentrated, accelerating reactions within the aerosol matrix that lead to a 42% reduction in peroxide content and noticeable browning of the SOA. This process occurs most effectively at moderate relative humidity (∼40%), reaching a maximum solute concentration before aerosol solidification. Molecular characterization reveals that evaporating VCP-derived SOA produces highly conjugated nitrogen-containing products from interactions between existing or transformed carbonyl compounds and reduced nitrogen species, likely acting as chromophores responsible for the observed brownish coloration. Additionally, the reactivity of VCP-derived SOA was elucidated through heterogeneous oxidation of sulfur dioxide (SO2), which revealed enhanced photosensitized sulfate production upon drying. Direct measurements of ROS, including singlet oxygen (1O2), superoxide (O2•-), and hydroxyl radicals (•OH), showed higher abundances in dried versus undried SOA samples under light exposure. Our findings underscore that drying significantly alters the physicochemical properties of VCP-derived SOA, impacting their roles in atmospheric chemistry and radiative balance.
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Affiliation(s)
- Liyuan Zhou
- Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal, Jeddah 23955-6900, Kingdom of Saudi Arabia
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon 999077, Hong Kong SAR, China
| | - Zhancong Liang
- Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal, Jeddah 23955-6900, Kingdom of Saudi Arabia
| | - Yiming Qin
- School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon 999077, Hong Kong SAR, China
| | - Chak K Chan
- Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal, Jeddah 23955-6900, Kingdom of Saudi Arabia
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3
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Brunet C, Marek RF, Stanier CO, Hornbuckle KC. Concentrations of Volatile Methyl Siloxanes in New York City Reflect Emissions from Personal Care and Industrial Use. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:8835-8845. [PMID: 38722766 PMCID: PMC11112754 DOI: 10.1021/acs.est.3c10752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 04/25/2024] [Accepted: 04/26/2024] [Indexed: 05/22/2024]
Abstract
Volatile methyl siloxanes (VMS) are a group of organosilicon compounds of interest because of their potential health effects, their ability to form secondary organic aerosols, and their use as tracer compounds. VMS are emitted in the gas-phase from using consumer and personal care products, including deodorants, lotions, and hair conditioners. Because of this emission route, airborne concentrations are expected to increase with population density, although there are few studies in large urban centers. Here, we report summertime concentrations and daily variations of VMS congeners measured in New York City. Median concentrations of the 6 studied congeners, D3 (20 ng m-3), D4 (57 ng m-3), D5 (230 ng m-3), D6 (11 ng m-3), L5 (2.5 ng m-3), and L7 (1.3 ng m-3) are among the highest reported outdoor concentrations in the literature to date. Average congener ratios of D5:D4 and D5:D6 were consistent with previously reported emissions ratios, suggesting that concentrations were dominated by local emissions. Measured concentrations agree with previously published results from a Community Multiscale Air Quality model and support commonly accepted emissions rates for D4, D5, and D6 of 32.8, 135, and 6.1 mg per capita per day. Concentrations of D4, D5, D6, L5, and L7 and total VMS were significantly lower during the day than during the night, consistent with daytime oxidation reactivity. Concentrations of D3 did not show the same diurnal trend but exhibited a strong directional dependence, suggesting that it may be emitted by industrial point sources in the area rather than personal care product use. Concentrations of all congeners had large temporal variations but showed relatively weak relationships with wind speed, temperature, and mixing height.
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Affiliation(s)
- Christopher
E. Brunet
- Department
of Civil and Environmental Engineering, IIHR-Hydroscience & Engineering, University of Iowa, Iowa City Iowa 52242, United States
| | - Rachel F. Marek
- Department
of Civil and Environmental Engineering, IIHR-Hydroscience & Engineering, University of Iowa, Iowa City Iowa 52242, United States
| | - Charles O. Stanier
- Department
of Chemical and Biochemical Engineering, IIHR-Hydroscience and Engineering, The University of Iowa, Iowa City Iowa 52242, United States
| | - Keri C. Hornbuckle
- Department
of Civil and Environmental Engineering, IIHR-Hydroscience & Engineering, University of Iowa, Iowa City Iowa 52242, United States
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4
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Agache I, Annesi-Maesano I, Cecchi L, Biagioni B, Chung KF, Clot B, D'Amato G, Damialis A, Del Giacco S, Dominguez-Ortega J, Galàn C, Gilles S, Holgate S, Jeebhay M, Kazadzis S, Nadeau K, Papadopoulos N, Quirce S, Sastre J, Tummon F, Traidl-Hoffmann C, Walusiak-Skorupa J, Jutel M, Akdis CA. EAACI guidelines on environmental science for allergy and asthma: The impact of short-term exposure to outdoor air pollutants on asthma-related outcomes and recommendations for mitigation measures. Allergy 2024. [PMID: 38563695 DOI: 10.1111/all.16103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 03/08/2024] [Accepted: 03/10/2024] [Indexed: 04/04/2024]
Abstract
The EAACI Guidelines on the impact of short-term exposure to outdoor pollutants on asthma-related outcomes provide recommendations for prevention, patient care and mitigation in a framework supporting rational decisions for healthcare professionals and patients to individualize and improve asthma management and for policymakers and regulators as an evidence-informed reference to help setting legally binding standards and goals for outdoor air quality at international, national and local levels. The Guideline was developed using the GRADE approach and evaluated outdoor pollutants referenced in the current Air Quality Guideline of the World Health Organization as single or mixed pollutants and outdoor pesticides. Short-term exposure to all pollutants evaluated increases the risk of asthma-related adverse outcomes, especially hospital admissions and emergency department visits (moderate certainty of evidence at specific lag days). There is limited evidence for the impact of traffic-related air pollution and outdoor pesticides exposure as well as for the interventions to reduce emissions. Due to the quality of evidence, conditional recommendations were formulated for all pollutants and for the interventions reducing outdoor air pollution. Asthma management counselled by the current EAACI guidelines can improve asthma-related outcomes but global measures for clean air are needed to achieve significant impact.
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Affiliation(s)
- Ioana Agache
- Faculty of Medicine, Transylvania University, Brasov, Romania
| | - Isabella Annesi-Maesano
- Institute Desbrest of Epidemiology and Public Health, University of Montpellier and INSERM, Montpellier, France
| | - Lorenzo Cecchi
- Centre of Bioclimatology, University of Florence, Florence, Italy
| | - Benedetta Biagioni
- Allergy and Clinical Immunology Unit San Giovanni di Dio Hospital, Florence, Italy
| | - Kian Fan Chung
- National Hearth & Lung Institute, Imperial College London, London, UK
| | - Bernard Clot
- Federal office of meteorology and climatology MeteoSwiss, Payerne, Switzerland
| | - Gennaro D'Amato
- Respiratory Disease Department, Hospital Cardarelli, Naples, Italy
- University of Naples Federico II Medical School of Respiratory Diseases, Naples, Italy
| | - Athanasios Damialis
- Department of Ecology, School of Biology, Faculty of Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Stefano Del Giacco
- Department of Medical Sciences and Public Health, University of Cagliari, Monserrato, Italy
| | - Javier Dominguez-Ortega
- Department of Allergy, La Paz University Hospital, IdiPAZ, and CIBER of Respiratory Diseases (CIBERES), Madrid, Spain
| | - Carmen Galàn
- Inter-University Institute for Earth System Research (IISTA), International Campus of Excellence on Agrifood (ceiA3), University of Córdoba, Córdoba, Spain
| | - Stefanie Gilles
- Environmental Medicine, Faculty of Medicine, University of Augsburg, Augsburg, Germany
| | - Stephen Holgate
- Faculty of Medicine, University of Southampton, Southampton, UK
| | - Mohamed Jeebhay
- Occupational Medicine Division and Centre for Environmental & Occupational Health Research, University of Cape Town, Cape Town, South Africa
| | - Stelios Kazadzis
- Physikalisch-Meteorologisches Observatorium Davos, World Radiation Center, Davos, Switzerland
| | - Kari Nadeau
- John Rock Professor of Climate and Population Studies, Department of Environmental Health, Center for Climate, Health, and the Global Environment, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
| | - Nikolaos Papadopoulos
- Allergy and Clinical Immunology Unit, Second Pediatric Clinic, National and Kapodistrian University of Athens, Athens, Greece
- Division of Evolution and Genomic Sciences, University of Manchester, Manchester, UK
| | - Santiago Quirce
- Department of Allergy, La Paz University Hospital, IdiPAZ, and CIBER of Respiratory Diseases (CIBERES), Madrid, Spain
| | - Joaquin Sastre
- Allergy Service, Fundación Jiménez Díaz, Faculty of Medicine Universidad Autónoma de Madrid and CIBERES, Instituto Carlos III, Ministry of Science and Innovation, Madrid, Spain
| | - Fiona Tummon
- Respiratory Disease Department, Hospital Cardarelli, Naples, Italy
- University of Naples Federico II Medical School of Respiratory Diseases, Naples, Italy
| | - Claudia Traidl-Hoffmann
- Department of Environmental Medicine, Faculty of Medicine, University of Augsburg, Augsburg, Germany
- Institute of Environmental Medicine, Helmholtz Center Munich-German Research Center for Environmental Health, Augsburg, Germany
- Christine Kühne Center for Allergy Research and Education, Davos, Switzerland
| | - Jolanta Walusiak-Skorupa
- Department of Occupational Diseases and Environmental Health, Nofer Institute of Occupational Medicine, Lodz, Poland
| | - Marek Jutel
- Department of Clinical Immunology, Wrocław Medical University, and ALL-MED Medical Research Institute, Wroclaw, Poland
| | - Cezmi A Akdis
- Swiss Institute of Allergy and Asthma Research (SIAF), University Zurich, Davos, Switzerland
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5
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Carter TJ, Shaw DR, Carslaw DC, Carslaw N. Indoor cooking and cleaning as a source of outdoor air pollution in urban environments. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2024. [PMID: 38525871 DOI: 10.1039/d3em00512g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/26/2024]
Abstract
Indoor sources of air pollution, such as from cooking and cleaning, play a key role in indoor gas-phase chemistry. The focus of the impact of these activities on air quality tends to be indoors, with less attention given to the impact on air quality outside buildings. This study uses the INdoor CHEmical Model in Python (INCHEM-Py) and the Advanced Dispersion Modelling System (ADMS) to quantify the impact cooking and cleaning have on indoor and outdoor air quality for an idealised street of houses. INCHEM-Py has been developed to determine the concentrations of 106 indoor volatile organic compounds at the point they leave a building (defined as near-field concentrations). For a simulated 140 m long street with 10 equi-distant houses undertaking cooking and cleaning activities, the maximum downwind concentration of acetaldehyde increases from a background value of 0.1 ppb to 0.9 ppb post-cooking, whilst the maximum downwind chloroform concentrations increase from 1.2 to 6.2 ppt after cleaning. Although emissions to outdoors are higher when cooking and cleaning happen indoors, the contribution of these activities to total UK emissions of volatile organic compounds is low (less than 1%), and comprise about a quarter of those emitted from traffic across the UK. It is important to quantify these emissions, particularly as continued vehicle technology improvements lead to lower direct emissions outdoors, making indoor emissions relatively more important. Understanding how indoor pollution can affect outdoor environments, will allow better mitigation measures to be designed in the future that can take into account all sources of pollution that contribute to human exposure.
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Affiliation(s)
- Toby J Carter
- Department of Environment and Geography, University of York, York, YO10 5NG, UK.
| | - David R Shaw
- Department of Environment and Geography, University of York, York, YO10 5NG, UK.
| | - David C Carslaw
- Department of Chemistry, University of York, York, YO10 5DD, UK
| | - Nicola Carslaw
- Department of Environment and Geography, University of York, York, YO10 5NG, UK.
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6
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Nassikas NJ, McCormack MC, Ewart G, Balmes JR, Bond TC, Brigham E, Cromar K, Goldstein AH, Hicks A, Hopke PK, Meyer B, Nazaroff WW, Paulin LM, Rice MB, Thurston GD, Turpin BJ, Vance ME, Weschler CJ, Zhang J, Kipen HM. Indoor Air Sources of Outdoor Air Pollution: Health Consequences, Policy, and Recommendations: An Official American Thoracic Society Workshop Report. Ann Am Thorac Soc 2024; 21:365-376. [PMID: 38426826 PMCID: PMC10913763 DOI: 10.1513/annalsats.202312-1067st] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2024] Open
Abstract
Indoor sources of air pollution worsen indoor and outdoor air quality. Thus, identifying and reducing indoor pollutant sources would decrease both indoor and outdoor air pollution, benefit public health, and help address the climate crisis. As outdoor sources come under regulatory control, unregulated indoor sources become a rising percentage of the problem. This American Thoracic Society workshop was convened in 2022 to evaluate this increasing proportion of indoor contributions to outdoor air quality. The workshop was conducted by physicians and scientists, including atmospheric and aerosol scientists, environmental engineers, toxicologists, epidemiologists, regulatory policy experts, and pediatric and adult pulmonologists. Presentations and discussion sessions were centered on 1) the generation and migration of pollutants from indoors to outdoors, 2) the sources and circumstances representing the greatest threat, and 3) effective remedies to reduce the health burden of indoor sources of air pollution. The scope of the workshop was residential and commercial sources of indoor air pollution in the United States. Topics included wood burning, natural gas, cooking, evaporative volatile organic compounds, source apportionment, and regulatory policy. The workshop concluded that indoor sources of air pollution are significant contributors to outdoor air quality and that source control and filtration are the most effective measures to reduce indoor contributions to outdoor air. Interventions should prioritize environmental justice: Households of lower socioeconomic status have higher concentrations of indoor air pollutants from both indoor and outdoor sources. We identify research priorities, potential health benefits, and mitigation actions to consider (e.g., switching from natural gas to electric stoves and transitioning to scent-free consumer products). The workshop committee emphasizes the benefits of combustion-free homes and businesses and recommends economic, legislative, and education strategies aimed at achieving this goal.
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7
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Dolan RH, Wallington TJ, Anderson JE. Large Decreases in Tailpipe Criteria Pollutant Emissions from the U.S. Light-Duty Vehicle Fleet Expected in 2020-2040. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024. [PMID: 38323898 DOI: 10.1021/acs.est.3c04554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2024]
Abstract
The U.S. EPA MOVES3 model was used to assess the impact of the large-scale introduction of electric vehicles on emissions of criteria pollutants (CO, hydrocarbons [HC], NOx, and particulate matter [PM]) and CO2 from the U.S. light-duty vehicle fleet. Large reductions in emissions of these criteria pollutants occurred in 2000-2020. These trends are expected to continue through 2040 driven by turnover of the conventional fleet with old vehicles being replaced by battery electric vehicles (BEVs) and by new internal combustion engine vehicles (ICEVs) with modern emission control systems. Without the introduction of BEVs, the absolute emissions of CO, NOx, HC, and PM2.5 from the U.S. light-duty vehicle fleet are expected to decrease by approximately 61, 88, 55, and 20% from 2020 to 2040. Introduction of BEVs with market share increasing linearly to 100% in 2040 provides additional benefits, which, combined with ICEV fleet turnover, would lead to decreases of absolute emissions of CO, NOx, HC, and PM2.5 of approximately 77, 94, 71, and 37% from 2020 to 2040. Reductions in CO2 emissions follow a similar pattern. Large decreases in criteria pollutant and CO2 emissions from light duty vehicles lie ahead.
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Affiliation(s)
- Rachael H Dolan
- Ford Motor Company, Research & Advanced Engineering, Dearborn, Michigan 48121, United States
| | - Timothy J Wallington
- Center for Sustainable Systems, School for Environment and Sustainability, University of Michigan, Ann Arbor, Michigan 48019, United States
| | - James E Anderson
- Ford Motor Company, Research & Advanced Engineering, Dearborn, Michigan 48121, United States
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8
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Cao L, Men Q, Zhang Z, Yue H, Cui S, Huang X, Zhang Y, Wang J, Chen M, Li H. Significance of Volatile Organic Compounds to Secondary Pollution Formation and Health Risks Observed during a Summer Campaign in an Industrial Urban Area. TOXICS 2024; 12:34. [PMID: 38250990 PMCID: PMC10820161 DOI: 10.3390/toxics12010034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 12/20/2023] [Accepted: 12/22/2023] [Indexed: 01/23/2024]
Abstract
The chemical complexity and toxicity of volatile organic compounds (VOCs) are primarily encountered through intensive anthropogenic emissions in suburban areas. Here, pollution characteristics, impacts on secondary pollution formation, and health risks were investigated through continuous in-field measurements from 1-30 June 2020 in suburban Nanjing, adjacent to national petrochemical industrial parks in China. On average, the total VOCs concentration was 34.47 ± 16.08 ppb, which was comprised mostly by alkanes (41.8%) and halogenated hydrocarbons (29.4%). In contrast, aromatics (17.4%) dominated the ozone formation potential (OFP) and secondary organic aerosol formation potential (SOAFP) with 59.6% and 58.3%, respectively. Approximately 63.5% of VOCs were emitted from the petrochemical industry and from solvent usage based on source apportionment results, followed by biogenic emissions of 22.3% and vehicle emissions of 14.2%. Of the observed 46 VOC species, hexachlorobutadiene, dibromoethane, butadiene, tetrachloroethane, and vinyl chloride contributed as high as 98.8% of total carcinogenic risk, a large fraction of which was ascribed to the high-level emissions during ozone pollution episodes and nighttime. Therefore, the mitigation of VOC emissions from petrochemical industries would be an effective way to reduce secondary pollution and potential health risks in conurbation areas.
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Affiliation(s)
- Li Cao
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Qihui Men
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Zihao Zhang
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Hao Yue
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Shijie Cui
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Xiangpeng Huang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China
| | - Yunjiang Zhang
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Junfeng Wang
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Mindong Chen
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Haiwei Li
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environment Sciences, Shanghai 200233, China
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9
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Yu H, Møller KH, Buenconsejo RS, Crounse JD, Kjaergaard HG, Wennberg PO. Atmospheric Photo-Oxidation of 2-Ethoxyethanol: Autoxidation Chemistry of Glycol Ethers. J Phys Chem A 2023; 127:9564-9579. [PMID: 37934888 DOI: 10.1021/acs.jpca.3c04456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2023]
Abstract
We investigate the gas-phase photo-oxidation of 2-ethoxyethanol (2-EE) initiated by the OH radical with a focus on its autoxidation pathways. Gas-phase autoxidation─intramolecular H-shifts followed by O2 addition─has recently been recognized as a major atmospheric chemical pathway that leads to the formation of highly oxygenated organic molecules (HOMs), which are important precursors for secondary organic aerosols (SOAs). Here, we examine the gas-phase oxidation pathways of 2-EE, a model compound for glycol ethers, an important class of volatile organic compounds (VOCs) used in volatile chemical products (VCPs). Both experimental and computational techniques are applied to analyze the photochemistry of the compound. We identify oxidation products from both bimolecular and autoxidation reactions from chamber experiments at varied HO2 levels and provide estimations of rate coefficients and product branching ratios for key reaction pathways. The H-shift processes of 2-EE peroxy radicals (RO2) are found to be sufficiently fast to compete with bimolecular reactions under modest NO/HO2 conditions. More than 30% of the produced RO2 are expected to undergo at least one H-shift for conditions typical of modern summer urban atmosphere, where RO2 bimolecular lifetime is becoming >10 s, which implies the potential for glycol ether oxidation to produce considerable amounts of HOMs at reduced NOx levels and elevated temperature. Understanding the gas-phase autoxidation of glycol ethers can help fill the knowledge gap in the formation of SOA derived from oxygenated VOCs emitted from VCP sources.
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Affiliation(s)
- Hongmin Yu
- Division of Geological and Planetary Sciences, California Institute of Technology, 1200 E California Blvd., Pasadena, California 91125, United States
| | - Kristian H Møller
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, Copenhagen Ø DK-2100, Denmark
| | - Reina S Buenconsejo
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E California Blvd., Pasadena, California 91125, United States
| | - John D Crounse
- Division of Geological and Planetary Sciences, California Institute of Technology, 1200 E California Blvd., Pasadena, California 91125, United States
| | - Henrik G Kjaergaard
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, Copenhagen Ø DK-2100, Denmark
| | - Paul O Wennberg
- Division of Geological and Planetary Sciences, California Institute of Technology, 1200 E California Blvd., Pasadena, California 91125, United States
- Division of Engineering and Applied Science, California Institute of Technology, 1200 E California Blvd., Pasadena, California 91125, United States
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10
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Huang L, Zhao B, Wang S, Chang X, Klimont Z, Huang G, Zheng H, Hao J. Global Anthropogenic Emissions of Full-Volatility Organic Compounds. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:16435-16445. [PMID: 37853753 DOI: 10.1021/acs.est.3c04106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2023]
Abstract
Traditional global emission inventories classify primary organic emissions into nonvolatile organic carbon and volatile organic compounds (VOCs), excluding intermediate-volatility and semivolatile organic compounds (IVOCs and SVOCs, respectively), which are important precursors of secondary organic aerosols. This study establishes the first global anthropogenic full-volatility organic emission inventory with chemically speciated or volatility-binned emission factors. The emissions of extremely low/low-volatility organic compounds (xLVOCs), SVOCs, IVOCs, and VOCs in 2015 were 13.2, 10.1, 23.3, and 120.5 Mt, respectively. The full-volatility framework fills a gap of 18.5 Mt I/S/xLVOCs compared with the traditional framework. Volatile chemical products (VCPs), domestic combustion, and on-road transportation sources were dominant contributors to full-volatility emissions, accounting for 30, 30, and 12%, respectively. The VCP and on-road transportation sectors were the main contributors to IVOCs and VOCs. The key emitting regions included Africa, India, Southeast Asia, China, Europe, and the United States, among which China, Europe, and the United States emitted higher proportions of IVOCs and VOCs owing to the use of cleaner fuel in domestic combustion and more intense emissions from VCPs and on-road transportation activities. The findings contribute to a better understanding of the impact of organic emissions on global air pollution and climate change.
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Affiliation(s)
- Lyuyin Huang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
- State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
| | - Bin Zhao
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
- State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
| | - Shuxiao Wang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
- State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
| | - Xing Chang
- Laboratory of Transport Pollution Control and Monitoring Technology, Transport Planning and Research Institute, Ministry of Transport, Beijing 100028, China
| | - Zbigniew Klimont
- International Institute for Applied Systems Analysis (IIASA), Laxenburg 2361, Austria
| | - Guanghan Huang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
- State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
| | - Haotian Zheng
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
- State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
| | - Jiming Hao
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
- State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
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11
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Pfannerstill EY, Arata C, Zhu Q, Schulze BC, Woods R, Harkins C, Schwantes RH, McDonald BC, Seinfeld JH, Bucholtz A, Cohen RC, Goldstein AH. Comparison between Spatially Resolved Airborne Flux Measurements and Emission Inventories of Volatile Organic Compounds in Los Angeles. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:15533-15545. [PMID: 37791848 PMCID: PMC10586371 DOI: 10.1021/acs.est.3c03162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 09/19/2023] [Accepted: 09/20/2023] [Indexed: 10/05/2023]
Abstract
Los Angeles is a major hotspot for ozone and particulate matter air pollution in the United States. Ozone and PM2.5 in this region have not improved substantially for the past decade, despite a reduction in vehicular emissions of their precursors, NOx and volatile organic compounds (VOCs). This reduction in "traditional" sources has made the current emission mixture of air pollutant precursors more uncertain. To map and quantify emissions of a wide range of VOCs in this urban area, we performed airborne eddy covariance measurements with wavelet analysis. VOC fluxes measured include tracers for source categories, such as traffic, vegetation, and volatile chemical products (VCPs). Mass fluxes were dominated by oxygenated VOCs, with ethanol contributing ∼29% of the total. In terms of OH reactivity and aerosol formation potential, terpenoids contributed more than half. Observed fluxes were compared with two commonly used emission inventories: the California Air Resources Board inventory and the combination of the Biogenic Emission Inventory System with the Fuel-based Inventory of Vehicle Emissions combined with Volatile Chemical Products (FIVE-VCP). The comparison shows mismatches regarding the amount, spatial distribution, and weekend effects of observed VOC emissions with the inventories. The agreement was best for typical transportation related VOCs, while discrepancies were larger for biogenic and VCP-related VOCs.
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Affiliation(s)
- Eva Y. Pfannerstill
- Department
of Environmental Science, Policy and Management, University of California at Berkeley, Berkeley 94720, California, United States
| | - Caleb Arata
- Department
of Environmental Science, Policy and Management, University of California at Berkeley, Berkeley 94720, California, United States
| | - Qindan Zhu
- Department
of Earth and Planetary Science, University
of California at Berkeley, Berkeley 94720, California, United States
- Cooperative
Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder 80305, Colorado, United States
| | - Benjamin C. Schulze
- Department
of Environmental Science and Engineering, California Institute of Technology, Pasadena 91125, California, United States
| | - Roy Woods
- Department
of Meteorology, Naval Postgraduate School, Monterey 93943, California, United
States
| | - Colin Harkins
- Cooperative
Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder 80305, Colorado, United States
- NOAA Chemical
Sciences Laboratory, Boulder 80305, Colorado, United States
| | | | - Brian C. McDonald
- NOAA Chemical
Sciences Laboratory, Boulder 80305, Colorado, United States
| | - John H. Seinfeld
- Department
of Environmental Science and Engineering, California Institute of Technology, Pasadena 91125, California, United States
| | - Anthony Bucholtz
- Department
of Meteorology, Naval Postgraduate School, Monterey 93943, California, United
States
| | - Ronald C. Cohen
- Department
of Earth and Planetary Science, University
of California at Berkeley, Berkeley 94720, California, United States
- Department
of Chemistry, University of California at
Berkeley, Berkeley 94720, California, United States
| | - Allen H. Goldstein
- Department
of Environmental Science, Policy and Management, University of California at Berkeley, Berkeley 94720, California, United States
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12
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Sasidharan S, He Y, Akherati A, Li Q, Li W, Cocker D, McDonald BC, Coggon MM, Seltzer KM, Pye HOT, Pierce JR, Jathar SH. Secondary Organic Aerosol Formation from Volatile Chemical Product Emissions: Model Parameters and Contributions to Anthropogenic Aerosol. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:11891-11902. [PMID: 37527511 DOI: 10.1021/acs.est.3c00683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/03/2023]
Abstract
Volatile chemical products (VCP) are an increasingly important source of hydrocarbon and oxygenated volatile organic compound (OVOC) emissions to the atmosphere, and these emissions are likely to play an important role as anthropogenic precursors for secondary organic aerosol (SOA). While the SOA from VCP hydrocarbons is often accounted for in models, the formation, evolution, and properties of SOA from VCP OVOCs remain uncertain. We use environmental chamber data and a kinetic model to develop SOA parameters for 10 OVOCs representing glycols, glycol ethers, esters, oxygenated aromatics, and amines. Model simulations suggest that the SOA mass yields for these OVOCs are of the same magnitude as widely studied SOA precursors (e.g., long-chain alkanes, monoterpenes, and single-ring aromatics), and these yields exhibit a linear correlation with the carbon number of the precursor. When combined with emissions inventories for two megacities in the United States (US) and a US-wide inventory, we find that VCP VOCs react with OH to form 0.8-2.5× as much SOA, by mass, as mobile sources. Hydrocarbons (terpenes, branched and cyclic alkanes) and OVOCs (terpenoids, glycols, glycol ethers) make up 60-75 and 25-40% of the SOA arising from VCP use, respectively. This work contributes to the growing body of knowledge focused on studying VCP VOC contributions to urban air pollution.
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Affiliation(s)
- Sreejith Sasidharan
- Mechanical Engineering, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Yicong He
- Mechanical Engineering, Colorado State University, Fort Collins, Colorado 80523, United States
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
- State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
| | - Ali Akherati
- Mechanical Engineering, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Qi Li
- Chemical and Environmental Engineering, University of California Riverside, Riverside, California 92521, United States
| | - Weihua Li
- Chemical and Environmental Engineering, University of California Riverside, Riverside, California 92521, United States
| | - David Cocker
- Chemical and Environmental Engineering, University of California Riverside, Riverside, California 92521, United States
| | - Brian C McDonald
- Chemical Sciences Laboratory, National Oceanic and Atmospheric Administration, Boulder, Colorado 80305, United States
| | - Matthew M Coggon
- Chemical Sciences Laboratory, National Oceanic and Atmospheric Administration, Boulder, Colorado 80305, United States
| | - Karl M Seltzer
- Office of Air and Radiation, Environmental Protection Agency, Research Triangle Park, North Carolina 27709, United States
| | - Havala O T Pye
- Office of Research and Development, Environmental Protection Agency, Research Triangle Park, North Carolina 27709, United States
| | - Jeffrey R Pierce
- Atmospheric Science, Colorado State University, Fort Collins, Colorado 80521, United States
| | - Shantanu H Jathar
- Mechanical Engineering, Colorado State University, Fort Collins, Colorado 80523, United States
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13
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Cao C, Gentner DR, Commane R, Toledo-Crow R, Schiferl LD, Mak JE. Policy-Related Gains in Urban Air Quality May Be Offset by Increased Emissions in a Warming Climate. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023. [PMID: 37327457 DOI: 10.1021/acs.est.2c05904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Air quality policies have made substantial gains by reducing pollutant emissions from the transportation sector. In March 2020, New York City's activities were severely curtailed in response to the COVID-19 pandemic, resulting in 60-90% reductions in human activity. We continuously measured major volatile organic compounds (VOCs) during January-April 2020 and 2021 in Manhattan. Concentrations of many VOCs decreased significantly during the shutdown with variations in daily patterns reflective of human activity perturbations, resulting in a temporary ∼28% reduction in chemical reactivity. However, the limited effect of these dramatic measures was outweighed by larger increases in VOC-related reactivity during the anomalously warm spring 2021. This emphasizes the diminishing returns from transportation-focused policies alone and the risk of increased temperature-dependent emissions undermining policy-related gains in a warming climate.
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Affiliation(s)
- Cong Cao
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, New York 11794, United States
| | - Drew R Gentner
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06511, United States
| | - Róisín Commane
- Department of Earth and Environmental Sciences, Columbia University, New York, New York 10027, United States
- Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York 10964, United States
| | - Ricardo Toledo-Crow
- Advanced Science Research Center, City University of New York, New York, New York 10031, United States
| | - Luke D Schiferl
- Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York 10964, United States
| | - John E Mak
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, New York 11794, United States
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14
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Klimkaite L, Liveikis T, Kaspute G, Armalyte J, Aldonyte R. Air pollution-associated shifts in the human airway microbiome and exposure-associated molecular events. Future Microbiol 2023; 18:607-623. [PMID: 37477532 DOI: 10.2217/fmb-2022-0258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/22/2023] Open
Abstract
Publications addressing air pollution-induced human respiratory microbiome shifts are reviewed in this article. The healthy respiratory microbiota is characterized by a low density of bacteria, fungi and viruses with high diversity, and usually consists of Bacteroidetes, Firmicutes, Proteobacteria, Actinobacteria, Fusobacteria, viruses and fungi. The air's microbiome is highly dependent on air pollution levels and is directly reflected within the human respiratory microbiome. In addition, pollutants indirectly modify the local environment in human respiratory organs by reducing antioxidant capacity, misbalancing proteolysis and modulating inflammation, all of which regulate local microbiomes. Improving air quality leads to more diverse and healthy microbiomes of the local air and, subsequently, residents' airways.
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Affiliation(s)
| | | | - Greta Kaspute
- State Research Institute Center for Innovative Medicine, Vilnius, Lithuania
| | | | - Ruta Aldonyte
- State Research Institute Center for Innovative Medicine, Vilnius, Lithuania
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15
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Asif Z, Chen Z, Haghighat F, Nasiri F, Dong J. Estimation of Anthropogenic VOCs Emission Based on Volatile Chemical Products: A Canadian Perspective. ENVIRONMENTAL MANAGEMENT 2023; 71:685-703. [PMID: 36416924 PMCID: PMC9685044 DOI: 10.1007/s00267-022-01732-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 10/02/2022] [Indexed: 06/16/2023]
Abstract
Volatile organic compounds (VOCs) in urban areas are of great interest due to their significant role in forming ground-level ozone and adverse public health effects. Emission inventories usually compile the outdoor VOCs emission sources (e.g., traffic and industrial emissions). However, considering emissions from volatile chemical products (e.g., solvents, printing ink, personal care products) is challenging because of scattered data and the lack of an effective method to estimate the VOCs emission rate from these chemical products. This paper aims to systematically analyse potential sources of VOCs emission in Canada's built environment, including volatile chemical products. Also, spatial variation of VOCs level in the ambient atmosphere is examined to understand the VOC relationship with ozone and secondary organic aerosol formation. The study shows that VOCs level may vary among everyday microenvironments (e.g., residential areas, offices, and retail stores) depending on the frequency of product consumption, building age, ventilation condition, and background ambient concentration in the atmosphere. However, it is very difficult to establish VOC speciation and apportionment to different volatile chemical products that contribute most significantly to exposure and target subpopulations with elevated levels. Thus, tracer compounds can be used to identify inventory sources at the consumer end. A critical overview highlights the limitations of existing VOC estimation methods and possible approaches to control VOC emissions. The findings provide crucial information to establish an emission inventory framework for volatile chemical products at a national scale and enable policymakers to limit VOCs emission from various volatile chemical products.
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Affiliation(s)
- Zunaira Asif
- Department of Building, Civil and Environmental Engineering, Concordia University, Montreal, QC, Canada
| | - Zhi Chen
- Department of Building, Civil and Environmental Engineering, Concordia University, Montreal, QC, Canada.
| | - Fariborz Haghighat
- Department of Building, Civil and Environmental Engineering, Concordia University, Montreal, QC, Canada
| | - Fuzhan Nasiri
- Department of Building, Civil and Environmental Engineering, Concordia University, Montreal, QC, Canada
| | - Jinxin Dong
- Department of Building, Civil and Environmental Engineering, Concordia University, Montreal, QC, Canada
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16
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Liang X, Chen L, Liu M, Lu H, Lu Q, Gao B, Zhao W, Sun X, Ye D. Improved emission factors and speciation to characterize VOC emissions in the printing industry in China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 866:161295. [PMID: 36592911 DOI: 10.1016/j.scitotenv.2022.161295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 12/07/2022] [Accepted: 12/27/2022] [Indexed: 06/17/2023]
Abstract
Printing industry is one of the most important sources of industrial volatile organic compound (VOC) emissions in China, and is thus a key industrial sector in terms of VOC control. However, process-based VOC emission and speciation from the printing industry have not been well identified, mainly owing to the poor emission factors (EFs) and diversity of source profiles. In this study, we systematically characterized process-based VOC emissions from the printing industry for the period of 2010-2019, through the establishment of improved emission factors and composite source profiles. VOC emissions from the printing industry were found to continuously increase from 2010 to 2018, reaching their maximum in 2018 at 939.8 Gg, but started to decrease afterwards. The substantial growth is driven by the large demand for ink and adhesive and the absence of effective control measures in the printing industry. The total VOC emissions and ozone formation potential (OFP) in China in 2019 were 916.1 Gg and 1834.5 Gg, respectively. Gravure printing and the compound process were the processes that contributed the most to both emissions and OFP. Rapidly developing provinces such as Guangdong, Jiangsu, and Zhejiang were the largest contributors to emissions. Oxygenated VOCs (OVOCs) accounted for most of the VOC emissions, followed by alkanes and aromatics, while aromatics were the dominant groups for total OFP, followed by alkenes/alkynes and OVOCs. Ethyl acetate, toluene, isopropanol, isopentane, and n-pentane were the top five VOC species in terms of emissions, while toluene, ethyl acetate, 1,3-butadiene, isopentane, and 1-butene were the top five species in terms of OFP. Scientific and precise control policy were proposed, involving four aspects: environmental access, emission standards, classification and management, and research on source substitution. We believe our study will provide an important reference for the systematic characterization and control policy of VOC emissions from other industries.
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Affiliation(s)
- Xiaoming Liang
- Guangdong Provincial Key Laboratory of Water and Air Pollution Control, South China Institute of Environmental Science, Ministry of Ecology and Environment, Guangzhou 510655, China; School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Laiguo Chen
- Guangdong Provincial Key Laboratory of Water and Air Pollution Control, South China Institute of Environmental Science, Ministry of Ecology and Environment, Guangzhou 510655, China.
| | - Ming Liu
- Guangdong Provincial Key Laboratory of Water and Air Pollution Control, South China Institute of Environmental Science, Ministry of Ecology and Environment, Guangzhou 510655, China
| | - Haitao Lu
- Guangdong Provincial Key Laboratory of Water and Air Pollution Control, South China Institute of Environmental Science, Ministry of Ecology and Environment, Guangzhou 510655, China
| | - Qing Lu
- Guangdong Provincial Key Laboratory of Water and Air Pollution Control, South China Institute of Environmental Science, Ministry of Ecology and Environment, Guangzhou 510655, China
| | - Bo Gao
- Guangdong Provincial Key Laboratory of Water and Air Pollution Control, South China Institute of Environmental Science, Ministry of Ecology and Environment, Guangzhou 510655, China
| | - Wei Zhao
- Guangdong Provincial Key Laboratory of Water and Air Pollution Control, South China Institute of Environmental Science, Ministry of Ecology and Environment, Guangzhou 510655, China
| | - Xibo Sun
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; Guangdong Provincial Academy of Environmental Science, Guangzhou 510045, China
| | - Daiqi Ye
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
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17
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Dominutti PA, Hopkins JR, Shaw M, Mills GP, Le HA, Huy DH, Forster GL, Keita S, Hien TT, Oram DE. Evaluating major anthropogenic VOC emission sources in densely populated Vietnamese cities. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 318:120927. [PMID: 36565909 DOI: 10.1016/j.envpol.2022.120927] [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: 08/18/2022] [Revised: 12/19/2022] [Accepted: 12/20/2022] [Indexed: 06/17/2023]
Abstract
Volatile organic compounds (VOCs) play an important role in urban air pollution, both as primary pollutants and through their contribution to the formation of secondary pollutants, such as tropospheric ozone and secondary organic aerosols. In this study, more than 30 VOC species were continuously monitored in the two most populous cities in Vietnam, namely Ho Chi Minh City (HCMC, September-October 2018 and March 2019) and Hanoi (March 2019). In parallel with ambient VOC sampling, grab sampling was used to target the most prevalent regional-specific emission sources and estimate their emission factors (EFs). Emission ratios (ERs) obtained from ambient sampling were compared between Vietnamese cities and other cities across the globe. No significant differences were observed between HCMC and Hanoi, suggesting the presence of similar sources. Moreover, a good global agreement was obtained in the spatial comparison within a factor of 2, with greater ER for aromatics and pentanes obtained in the Vietnamese cities. The detailed analysis of sources included the evaluation of EF from passenger cars, buses, trucks, motorcycles, 3-wheeled motorcycles, waste burning, and coal-burning emissions. Our comparisons between ambient and near-source concentration profiles show that road transport sources are the main contributors to VOC concentrations in Vietnamese cities. VOC emissions were calculated from measured EF and consumption data available in Hanoi and compared with those estimated by a global emission inventory (EDGAR v4.3.2). The total VOC emissions from the road transport sector estimated by the inventory do not agree with those calculated from our observations which showed higher total emissions by a factor of 3. Furthermore, the inventory misrepresented the VOCs speciation, mainly for isoprene, monoterpenes, aromatics, and oxygenated compounds. Accounting for these differences in regional air quality models would lead to improved predictions of their impacts and help to prioritise pollution reduction strategies in the region.
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Affiliation(s)
- Pamela A Dominutti
- Wolfson Atmospheric Chemistry Laboratories, Department of Chemistry, University of York, York, YO10 5DD, United Kingdom.
| | - James R Hopkins
- Wolfson Atmospheric Chemistry Laboratories, Department of Chemistry, University of York, York, YO10 5DD, United Kingdom; National Centre for Atmospheric Science, University of York, York, YO10 5DD, UK
| | - Marvin Shaw
- Wolfson Atmospheric Chemistry Laboratories, Department of Chemistry, University of York, York, YO10 5DD, United Kingdom; National Centre for Atmospheric Science, University of York, York, YO10 5DD, UK
| | - Graham P Mills
- Centre for Ocean and Atmospheric Science, School of Environmental Sciences, University of East Anglia, Norwich, UK
| | - Hoang Anh Le
- Faculty of Environmental Sciences, University of Science, Vietnam National University, Hanoi, Viet Nam
| | - Duong Huu Huy
- Faculty of Food Science and Technology, Ho Chi Minh City University of Food Industry, Ho Chi Minh, Viet Nam
| | - Grant L Forster
- Centre for Ocean and Atmospheric Science, School of Environmental Sciences, University of East Anglia, Norwich, UK; National Centre for Atmospheric Science, School of Environmental Sciences, University of East Anglia, Norwich, United Kingdom
| | - Sekou Keita
- Département Mathématiques-Physique-Chimie, Université Peleforo Gon Coulibaly, BP 1328 Korhogo, Cote d'Ivoire
| | - To Thi Hien
- Faculty of Environment, University of Science, Ho Chi Minh, Viet Nam; Vietnam National University, Ho Chi Minh, Viet Nam
| | - David E Oram
- Centre for Ocean and Atmospheric Science, School of Environmental Sciences, University of East Anglia, Norwich, UK; National Centre for Atmospheric Science, School of Environmental Sciences, University of East Anglia, Norwich, United Kingdom
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18
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Tao M, Fiore AM, Jin X, Schiferl LD, Commane R, Judd LM, Janz S, Sullivan JT, Miller PJ, Karambelas A, Davis S, Tzortziou M, Valin L, Whitehill A, Civerolo K, Tian Y. Investigating Changes in Ozone Formation Chemistry during Summertime Pollution Events over the Northeastern United States. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:15312-15327. [PMID: 36219092 PMCID: PMC9670856 DOI: 10.1021/acs.est.2c02972] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 09/07/2022] [Accepted: 09/23/2022] [Indexed: 06/16/2023]
Abstract
Understanding the local-scale spatial and temporal variability of ozone formation is crucial for effective mitigation. We combine tropospheric vertical column densities (VCDTrop) of formaldehyde (HCHO) and nitrogen dioxide (NO2), referred to as HCHO-VCDTrop and NO2-VCDTrop, retrieved from airborne remote sensing and the TROPOspheric Monitoring Instrument (TROPOMI) with ground-based measurements to investigate changes in ozone precursors and the inferred chemical production regime on high-ozone days in May-August 2018 over two Northeast urban domains. Over New York City (NYC) and Baltimore/Washington D.C. (BAL/DC), HCHO-VCDTrop increases across the domain, but higher NO2-VCDTrop occurs mainly in urban centers on ozone exceedance days (when maximum daily 8 h average (MDA8) ozone exceeds 70 ppb at any monitor in the region). The ratio of HCHO-VCDTrop to NO2-VCDTrop, proposed as an indicator of the sensitivity of local surface ozone production rates to its precursors, generally increases on ozone exceedance days, implying a transition toward a more NOx-sensitive ozone production regime that should lead to higher efficacy of NOx controls on the highest ozone days in NYC and BAL/DC. Warmer temperatures and enhanced influence from emissions in the local boundary layer on the high-ozone days are accompanied by slower wind speeds in BAL/DC but stronger, southwesterly winds in NYC.
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Affiliation(s)
- Madankui Tao
- Lamont-Doherty
Earth Observatory, Columbia University, Palisades, New York10964, United States
- Department
of Earth and Environmental Sciences, Columbia
University, New York, New York10027, United
States
| | - Arlene M. Fiore
- Lamont-Doherty
Earth Observatory, Columbia University, Palisades, New York10964, United States
- Department
of Earth and Environmental Sciences, Columbia
University, New York, New York10027, United
States
| | - Xiaomeng Jin
- Department
of Chemistry, University of California,
Berkeley, Berkeley, California94720, United States
| | - Luke D. Schiferl
- Lamont-Doherty
Earth Observatory, Columbia University, Palisades, New York10964, United States
| | - Róisín Commane
- Lamont-Doherty
Earth Observatory, Columbia University, Palisades, New York10964, United States
- Department
of Earth and Environmental Sciences, Columbia
University, New York, New York10027, United
States
| | - Laura M. Judd
- NASA
Langley Research Center, Hampton, Virginia23681, United States
| | - Scott Janz
- NASA
Goddard Space Flight Center, Greenbelt, Maryland20771, United States
| | - John T. Sullivan
- NASA
Goddard Space Flight Center, Greenbelt, Maryland20771, United States
| | - Paul J. Miller
- Northeast
States for Coordinated Air Use Management, Boston, Massachusetts02111, United States
| | - Alexandra Karambelas
- Northeast
States for Coordinated Air Use Management, Boston, Massachusetts02111, United States
| | - Sharon Davis
- New
Jersey Department of Environmental Protection, Trenton, New Jersey08625, United States
| | - Maria Tzortziou
- The
City College of New York, New York, New York10031, United States
| | - Lukas Valin
- US
Environmental Protection Agency, Research Triangle Park, North Carolina27711, United States
| | - Andrew Whitehill
- US
Environmental Protection Agency, Research Triangle Park, North Carolina27711, United States
| | - Kevin Civerolo
- New
York State Department of Environmental Conservation, Albany, New York12233, United States
| | - Yuhong Tian
- New
York State Department of Environmental Conservation, Albany, New York12233, United States
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19
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Khare P, Krechmer JE, Machesky JE, Hass-Mitchell T, Cao C, Wang J, Majluf F, Lopez-Hilfiker F, Malek S, Wang W, Seltzer K, Pye HO, Commane R, McDonald BC, Toledo-Crow R, Mak JE, Gentner DR. Ammonium-adduct chemical ionization to investigate anthropogenic oxygenated gas-phase organic compounds in urban air. ATMOSPHERIC CHEMISTRY AND PHYSICS 2022; 22:14377-14399. [PMID: 36506646 PMCID: PMC9728622 DOI: 10.5194/acp-22-14377-2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Volatile chemical products (VCPs) and other non-combustion-related sources have become important for urban air quality, and bottom-up calculations report emissions of a variety of functionalized compounds that remain understudied and uncertain in emissions estimates. Using a new instrumental configuration, we present online measurements of oxygenated organic compounds in a U.S. megacity over a 10-day wintertime sampling period, when biogenic sources and photochemistry were less active. Measurements were conducted at a rooftop observatory in upper Manhattan, New York City, USA using a Vocus chemical ionization time-of-flight mass spectrometer with ammonium (NH4 +) as the reagent ion operating at 1 Hz. The range of observations spanned volatile, intermediate-volatility, and semi-volatile organic compounds with targeted analyses of ~150 ions whose likely assignments included a range of functionalized compound classes such as glycols, glycol ethers, acetates, acids, alcohols, acrylates, esters, ethanolamines, and ketones that are found in various consumer, commercial, and industrial products. Their concentrations varied as a function of wind direction with enhancements over the highly-populated areas of the Bronx, Manhattan, and parts of New Jersey, and included abundant concentrations of acetates, acrylates, ethylene glycol, and other commonly-used oxygenated compounds. The results provide top-down constraints on wintertime emissions of these oxygenated/functionalized compounds with ratios to common anthropogenic marker compounds, and comparisons of their relative abundances to two regionally-resolved emissions inventories used in urban air quality models.
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Affiliation(s)
- Peeyush Khare
- Department of Chemical and Environmental Engineering, Yale University, New Haven CT-06511 USA
| | | | - Jo Ellen Machesky
- Department of Chemical and Environmental Engineering, Yale University, New Haven CT-06511 USA
| | - Tori Hass-Mitchell
- Department of Chemical and Environmental Engineering, Yale University, New Haven CT-06511 USA
| | - Cong Cao
- School of Marine and Atmospheric Science, Stony Brook University, Stony Brook NY-11794 USA
| | - Junqi Wang
- Department of Chemical and Environmental Engineering, Yale University, New Haven CT-06511 USA
| | | | | | - Sonja Malek
- Department of Chemical and Environmental Engineering, Yale University, New Haven CT-06511 USA
| | - Will Wang
- Department of Chemical and Environmental Engineering, Yale University, New Haven CT-06511 USA
| | - Karl Seltzer
- Office of Air and Radiation, Environmental Protection Agency, Research Triangle Park, NC-27711 USA
| | - Havala O.T. Pye
- Office of Research and Development, Environmental Protection Agency, Research Triangle Park, NC-27711 USA
| | - Roisin Commane
- Department of Earth and Environmental Sciences, Lamont-Doherty Earth Observatory, Columbia University, New York, NY-10027 USA
| | - Brian C. McDonald
- Chemical Sciences Laboratory, National Oceanic and Atmospheric Administration, Boulder CO- USA
| | - Ricardo Toledo-Crow
- Advanced Science Research Center, City University of New York, New York, NY-10031 USA
| | - John E. Mak
- School of Marine and Atmospheric Science, Stony Brook University, Stony Brook NY-11794 USA
| | - Drew R. Gentner
- Department of Chemical and Environmental Engineering, Yale University, New Haven CT-06511 USA
- School of the Environment, Yale University, New Haven CT-06511 USA
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20
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Dominutti PA, Chevassus E, Baray JL, Jaffrezo JL, Borbon A, Colomb A, Deguillaume L, El Gdachi S, Houdier S, Leriche M, Metzger JM, Rocco M, Tulet P, Sellegri K, Freney E. Evaluation of the Sources, Precursors, and Processing of Aerosols at a High-Altitude Tropical Site. ACS EARTH & SPACE CHEMISTRY 2022; 6:2412-2431. [PMID: 36303720 PMCID: PMC9590422 DOI: 10.1021/acsearthspacechem.2c00149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 08/02/2022] [Accepted: 08/02/2022] [Indexed: 06/16/2023]
Abstract
This work presents the results from a set of aerosol- and gas-phase measurements collected during the BIO-MAÏDO field campaign in Réunion between March 8 and April 5, 2019. Several offline and online sampling devices were installed at the Maïdo Observatory (MO), a remote high-altitude site in the Southern Hemisphere, allowing the physical and chemical characterization of atmospheric aerosols and gases. The evaluation of short-lived gas-phase measurements allows us to conclude that air masses sampled during this period contained little or no anthropogenic influence. The dominance of sulfate and organic species in the submicron fraction of the aerosol is similar to that measured at other coastal sites. Carboxylic acids on PM10 showed a significant contribution of oxalic acid, a typical tracer of aqueous processed air masses, increasing at the end of the campaign. This result agrees with the positive matrix factorization analysis of the submicron organic aerosol, where more oxidized organic aerosols (MOOAs) dominated the organic aerosol with an increasing contribution toward the end of the campaign. Using a combination of air mass trajectories (model predictions), it was possible to assess the impact of aqueous phase processing on the formation of secondary organic aerosols (SOAs). Our results show how specific chemical signatures and physical properties of air masses, possibly affected by cloud processing, can be identified at Réunion. These changes in properties are represented by a shift in aerosol size distribution to large diameters and an increased contribution of secondary sulfate and organic aerosols after cloud processing.
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Affiliation(s)
- Pamela A. Dominutti
- Université
Clermont-Auvergne, CNRS, UMR 6016, Laboratoire
de Météorologie Physique (LaMP), Clermont-Ferrand 63000, France
- Université
Grenoble Alpes, UMR 5001, CNRS, IRD, Institut des Géosciences
de l’Environnement (IGE), Grenoble 38400, France
| | - Emmanuel Chevassus
- Université
Clermont-Auvergne, CNRS, UMR 6016, Laboratoire
de Météorologie Physique (LaMP), Clermont-Ferrand 63000, France
| | - Jean-Luc Baray
- Université
Clermont-Auvergne, CNRS, UMR 6016, Laboratoire
de Météorologie Physique (LaMP), Clermont-Ferrand 63000, France
| | - Jean-Luc Jaffrezo
- Université
Grenoble Alpes, UMR 5001, CNRS, IRD, Institut des Géosciences
de l’Environnement (IGE), Grenoble 38400, France
| | - Agnès Borbon
- Université
Clermont-Auvergne, CNRS, UMR 6016, Laboratoire
de Météorologie Physique (LaMP), Clermont-Ferrand 63000, France
| | - Aurèlie Colomb
- Université
Clermont-Auvergne, CNRS, UMR 6016, Laboratoire
de Météorologie Physique (LaMP), Clermont-Ferrand 63000, France
| | - Laurent Deguillaume
- Université
Clermont-Auvergne, CNRS, UMR 6016, Laboratoire
de Météorologie Physique (LaMP), Clermont-Ferrand 63000, France
| | - Samira El Gdachi
- Laboratoire
d’Aérologie (LAERO), UMR 5560, Toulouse 31400, France
- Laboratoire
de l’Atmosphère et des Cyclones (LACy), UMR 8105, Université de la Réunion, Saint-Denis de La Réunion 97744, France
| | - Stephan Houdier
- Université
Grenoble Alpes, UMR 5001, CNRS, IRD, Institut des Géosciences
de l’Environnement (IGE), Grenoble 38400, France
| | - Maud Leriche
- Université
Clermont-Auvergne, CNRS, UMR 6016, Laboratoire
de Météorologie Physique (LaMP), Clermont-Ferrand 63000, France
- Centre
pour l’étude et la simulation du climat à l’échelle
régionale, Département des sciences de la terre et de
l’atmosphère (ESCER), Université
du Québec à Montréal, Montréal H2X 3Y7, Canada
| | - Jean-Marc Metzger
- Laboratoire
de l’Atmosphère et des Cyclones (LACy), UMR 8105, Université de la Réunion, Saint-Denis de La Réunion 97744, France
| | - Manon Rocco
- Université
Clermont-Auvergne, CNRS, UMR 6016, Laboratoire
de Météorologie Physique (LaMP), Clermont-Ferrand 63000, France
- Laboratoire
de l’Atmosphère et des Cyclones (LACy), UMR 8105, Université de la Réunion, Saint-Denis de La Réunion 97744, France
| | - Pierre Tulet
- Laboratoire
d’Aérologie (LAERO), UMR 5560, Toulouse 31400, France
| | - Karine Sellegri
- Université
Clermont-Auvergne, CNRS, UMR 6016, Laboratoire
de Météorologie Physique (LaMP), Clermont-Ferrand 63000, France
| | - Evelyn Freney
- Université
Clermont-Auvergne, CNRS, UMR 6016, Laboratoire
de Météorologie Physique (LaMP), Clermont-Ferrand 63000, France
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Zhu R, Fu Y, Wang L, Hu J, He L, Wang M, Lai Y, Su S. Effects of a start-stop system for gasoline direct injection vehicles on fuel consumption and particulate emissions in hot and cold environments. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 308:119689. [PMID: 35772619 DOI: 10.1016/j.envpol.2022.119689] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 06/07/2022] [Accepted: 06/24/2022] [Indexed: 06/15/2023]
Abstract
Engine start-stop (S&S) technology has been substantially incorporated into modern vehicles to save fuel during idling in congested urban areas because fuel economy regulations have become more stringent. However, the potential for increasing particle emissions after engine restarts, especially in cold environments, is of great concern. To investigate the effects of S&S systems on fuel consumption and tailpipe emissions, a chassis dynamometer was employed to measure the fuel consumption, particulate matter (PM), solid particle number (PN), particle number size distribution and black carbon (BC) for a typical gasoline direct injection vehicle when the S&S was on (S&S-on) and when the S&S was off (S&S-off) according to the worldwide harmonized light-duty test cycle in both hot (28 °C) and cold (5 °C) environments. S&S operation resulted in 3.1-4.3% fuel-savings at 28 °C but had a tendency to increase particulate emissions, especially of BC (21.8-31.8%) and PM (19.2-32.8%). Although PN emissions with S&S-on over the entire cycle were slightly lower than those with S&S-off, more particles were emitted during the engine restart moments. In a cold environment, the fuel-savings advantage of the S&S system was weakened, and the negative impacts on the particle emissions during the restart moment worsened. The S&S system resulted in higher abundances of accumulation mode particles, especially under cold ambient conditions. The relationship between the PN reduction rates and idling segments was determining to be exponential. Our results indicate that the S&S system, which may increase particle emissions during restarts, does save fuel, and that a comprehensive evaluation of the system in cold environments is needed to determine the serviceability of new engine technologies and after-treatments.
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Affiliation(s)
- Rencheng Zhu
- School of Ecology and Environment, Zhengzhou University, Zhengzhou, 450001, China; Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Yanan Fu
- School of Ecology and Environment, Zhengzhou University, Zhengzhou, 450001, China
| | - Lulu Wang
- School of Ecology and Environment, Zhengzhou University, Zhengzhou, 450001, China
| | - Jingnan Hu
- Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
| | - Liqiang He
- Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; School of Environment, State Key Joint Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, Beijing, 100084, China
| | - Menglei Wang
- School of Ecology and Environment, Zhengzhou University, Zhengzhou, 450001, China
| | - Yitu Lai
- Xiamen Environmental Protection Vehicle Emission Control Technology Center, Xiamen, 361023, China
| | - Sheng Su
- Xiamen Environmental Protection Vehicle Emission Control Technology Center, Xiamen, 361023, China
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22
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Michanowicz DR, Dayalu A, Nordgaard CL, Buonocore JJ, Fairchild MW, Ackley R, Schiff JE, Liu A, Phillips NG, Schulman A, Magavi Z, Spengler JD. Home is Where the Pipeline Ends: Characterization of Volatile Organic Compounds Present in Natural Gas at the Point of the Residential End User. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:10258-10268. [PMID: 35762409 PMCID: PMC9301916 DOI: 10.1021/acs.est.1c08298] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The presence of volatile organic compounds (VOCs) in unprocessed natural gas (NG) is well documented; however, the degree to which VOCs are present in NG at the point of end use is largely uncharacterized. We collected 234 whole NG samples across 69 unique residential locations across the Greater Boston metropolitan area, Massachusetts. NG samples were measured for methane (CH4), ethane (C2H6), and nonmethane VOC (NMVOC) content (including tentatively identified compounds) using commercially available USEPA analytical methods. Results revealed 296 unique NMVOC constituents in end use NG, of which 21 (or approximately 7%) were designated as hazardous air pollutants. Benzene (bootstrapped mean = 164 ppbv; SD = 16; 95% CI: 134-196) was detected in 95% of samples along with hexane (98% detection), toluene (94%), heptane (94%), and cyclohexane (89%), contributing to a mean total concentration of NMVOCs in distribution-grade NG of 6.0 ppmv (95% CI: 5.5-6.6). While total VOCs exhibited significant spatial variability, over twice as much temporal variability was observed, with a wintertime NG benzene concentration nearly eight-fold greater than summertime. By using previous NG leakage data, we estimated that 120-356 kg/yr of annual NG benzene emissions throughout Greater Boston are not currently accounted for in emissions inventories, along with an unaccounted-for indoor portion. NG-odorant content (tert-butyl mercaptan and isopropyl mercaptan) was used to estimate that a mean NG-CH4 concentration of 21.3 ppmv (95% CI: 16.7-25.9) could persist undetected in ambient air given known odor detection thresholds. This implies that indoor NG leakage may be an underappreciated source of both CH4 and associated VOCs.
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Affiliation(s)
- Drew R. Michanowicz
- Harvard
T.H. Chan School of Public Health, C-CHANGE, Boston, Massachusetts 02215 United States
- PSE
Healthy Energy, Oakland, California 94612, United States
- ,
| | - Archana Dayalu
- Atmospheric
and Environmental Research (AER), Lexington, Massachusetts 02421, United States
| | | | - Jonathan J. Buonocore
- Harvard
T.H. Chan School of Public Health, C-CHANGE, Boston, Massachusetts 02215 United States
| | - Molly W. Fairchild
- Home
Energy Efficiency Team (HEET), Cambridge, Massachusetts 02139, United States
| | - Robert Ackley
- Gas
Safety Inc., Southborough, Massachusetts 01772, United States
| | - Jessica E. Schiff
- Harvard
T.H. Chan School of Public Health, Boston, Massachusetts 02215, United States
| | - Abbie Liu
- Harvard
T.H. Chan School of Public Health, Boston, Massachusetts 02215, United States
| | | | - Audrey Schulman
- Home
Energy Efficiency Team (HEET), Cambridge, Massachusetts 02139, United States
| | - Zeyneb Magavi
- Home
Energy Efficiency Team (HEET), Cambridge, Massachusetts 02139, United States
| | - John D. Spengler
- Harvard
T.H. Chan School of Public Health, Boston, Massachusetts 02215, United States
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23
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Paul S, Bari MA. Elucidating sources of VOCs in the Capital Region of New York State: Implications to secondary transformation and public health exposure. CHEMOSPHERE 2022; 299:134407. [PMID: 35341770 DOI: 10.1016/j.chemosphere.2022.134407] [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: 11/15/2021] [Revised: 02/27/2022] [Accepted: 03/21/2022] [Indexed: 06/14/2023]
Abstract
Exposure to ambient volatile organic compounds (VOCs) in urban areas is of interest because of their potential adverse effects to public health. A study was carried out to elucidate ambient sources of VOCs in the Capital Region of New York State for the period 2015-2019. A combined dataset of VOCs and PM2.5 species was used in positive matrix factorization (PMF) model to better interpret the complex nature of different sources. Ten sources were revealed, where background source (3.8 μg/m3, 30%) was the largest contributor to VOCs, followed by petroleum-related emissions (2.9 μg/m3, 22%) and pyrolyzed oxygen (OP)-Elemental Carbon (EC2)-aldehydes-rich (2.7 μg/m3, 21%). Other notable VOC sources included methyl ethyl ketone (MEK)-rich, vehicular traffic, and biomass burning. Both OP-EC2-aldehydes-rich and petroleum-related emissions showed notable contribution to ozone (O3) and secondary organic aerosol (SOA) formation, respectively. Observed mean carcinogenic risk values of benzene and formaldehyde and 95th percentiles risk values of 1,3-butadiene and acetaldehyde were above the USEPA acceptable level of 1x10-6 but below a tolerable risk of 1x10-4. Estimated carcinogenic risk values of OP-EC2-aldehydes-rich, vehicular traffic, background and petroleum-related emissions were above the USEPA acceptable cancer risk and posed greater risk to public health (more than 80% of total carcinogenic risk) compared to other sources. Due to lack of some VOC species data (e.g., alkanes, alkenes, terpenes, alcohols), other urban VOC sources e.g., fugitive emissions, fuel evaporation, unburned fuel were not identified. More work is needed to better understand the contribution of VOC sources to O3 and SOA formation in Albany and surrounding region. Findings can support policy makers in developing appropriate air quality management initiatives for the Capital Region in New York State.
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24
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Seltzer KM, Murphy BN, Pennington EA, Allen C, Talgo K, Pye HOT. Volatile Chemical Product Enhancements to Criteria Pollutants in the United States. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:6905-6913. [PMID: 34779612 PMCID: PMC9247718 DOI: 10.1021/acs.est.1c04298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Volatile chemical products (VCPs) are a significant source of reactive organic carbon emissions in the United States with a substantial fraction (>20% by mass) serving as secondary organic aerosol (SOA) precursors. Here, we incorporate a new nationwide VCP inventory into the Community Multiscale Air Quality (CMAQ) model with VCP-specific updates to better model air quality impacts. Model results indicate that VCPs mostly enhance anthropogenic SOA in densely populated areas with population-weighted annual average SOA increasing 15-30% in Southern California and New York City due to VCP emissions (contribution of 0.2-0.5 μg m-3). Annually, VCP emissions enhance total population-weighted PM2.5 by ∼5% in California, ∼3% in New York, New Jersey, and Connecticut, and 1-2% in most other states. While the maximum daily 8 h ozone enhancements from VCP emissions are more modest, their influence can cause a several ppb increase on select days in major cities. Printing Inks, Cleaning Products, and Paints and Coatings product use categories contribute ∼75% to the modeled VCP-derived SOA and Cleaning Products, Paints and Coatings, and Personal Care Products contribute ∼81% to the modeled VCP-derived ozone. Overall, VCPs enhance multiple criteria pollutants throughout the United States with the largest impacts in urban cores.
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Affiliation(s)
- Karl M. Seltzer
- Oak Ridge Institute for Science and Education Postdoctoral Fellow in the Office of Research and Development, U.S. Environmental Protection Agency, 109 TW Alexander Dr, Research Triangle Park, NC 27711
| | - Benjamin N. Murphy
- Office of Research and Development, U.S. Environmental Protection Agency, 109 TW Alexander Dr, Research Triangle Park, NC 27711
| | - Elyse A. Pennington
- Department of Chemical Engineering, California Institute of Technology, Pasadena, CA 91125
| | - Chris Allen
- General Dynamics Information Technology, Research Triangle Park, NC, 27711
| | - Kevin Talgo
- General Dynamics Information Technology, Research Triangle Park, NC, 27711
| | - Havala O. T. Pye
- Office of Research and Development, U.S. Environmental Protection Agency, 109 TW Alexander Dr, Research Triangle Park, NC 27711
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25
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Fu Z, Xie HB, Elm J, Liu Y, Fu Z, Chen J. Atmospheric Autoxidation of Organophosphate Esters. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:6944-6955. [PMID: 34793133 DOI: 10.1021/acs.est.1c04817] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Organophosphate esters (OPEs), widely used as flame retardants and plasticizers, have frequently been identified in the atmosphere. However, their atmospheric fate and toxicity associated with atmospheric transformations are unclear. Here, we performed quantum chemical calculations and computational toxicology to investigate the reaction mechanism of peroxy radicals of OPEs (OPEs-RO2•), key intermediates in determining the atmospheric chemistry of OPEs, and the toxicity of the reaction products. TMP-RO2• (R1) and TCPP-RO2• (R2) derived from trimethyl phosphate and tris(2-chloroisopropyl) phosphate, respectively, are selected as model systems. The results indicate that R1 and R2 can follow an H-shift-driven autoxidation mechanism under low NO concentration ([NO]) conditions, clarifying that RO2• from esters can follow an autoxidation mechanism. The unexpected autoxidation mechanism can be attributed to the distinct role of the ─(O)3P(═O) phosphate-ester group in facilitating the H-shift of OPEs-RO2• from commonly encountered ─OC(═O)─ and ─ONO2 ester groups in the atmosphere. Under high [NO] conditions, NO can mediate the autoxidation mechanism to form organonitrates and alkoxy radical-related products. The products from the autoxidation mechanism have low volatility and aquatic toxicity compared to their corresponding parent compounds. The proposed autoxidation mechanism advances our current understanding of the atmospheric RO2• chemistry and the environmental risk of OPEs.
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Affiliation(s)
- Zihao Fu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Hong-Bin Xie
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Jonas Elm
- Department of Chemistry and iClimate, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark
| | - Yang Liu
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, China
| | - Zhiqiang Fu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Jingwen Chen
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
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26
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Kaikiti C, Stylianou M, Agapiou A. TD-GC/MS analysis of indoor air pollutants (VOCs, PM) in hair salons. CHEMOSPHERE 2022; 294:133691. [PMID: 35065178 DOI: 10.1016/j.chemosphere.2022.133691] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 01/01/2022] [Accepted: 01/17/2022] [Indexed: 06/14/2023]
Abstract
Hairdressing personnel is daily exposed to various chemical air pollutants, and specifically to Volatile Organic Compounds (VOCs) and Particulate Matter (PM) in hair salons. This is of concern, due to the hazardous effects of these chemicals on the individual's health. Nevertheless, a limited exposure assessment of indoor air quality (IAQ) has been performed. The aim of this study was to analyze the indoor air in 5 hair salons, to assess the IAQ of the occupational exposure, and to identify the main VOCs produced or activities responsible for the respective indoor pollution. The chemical analysis took place inside the salon environment by monitoring the emitted VOCs, as well as the PM of 1, 2.5, 4, and 10 μm aerodynamic diameter. The sampling of VOCs was performed by adsorption of pollutants on Tenax TA sorbent tubes, that were subsequently analyzed using a thermal desorption unit coupled to gas chromatography/mass spectrometry (TD-GC/MS). The obtained results showed that hair products are a major source of air pollutants, as elevated concentrations of VOCs and PM are released in the working environment. Furthermore, the type and concentration of VOCs are affected by the various hair treatment activities taking place in the salons. Among the main compounds detected there was benzene, toluene, ethylbenzene, and xylenes, known as BTEX, as well as, diethyl phthalate, 1,4-dioxane, etc. More than 50 VOCs were identified (occurrence ≥60%) and 14 of them were quantified. Their average concentration levels varied from 12 μg m-3 for naphthalene to 941 μg m-3 for toluene. The measuring levels for PM revealed violations of the EPA and WHO international standards for permissible limit concentrations; this was the case in all hair treatment activities but mostly during keratin treatment. Hence, much more effort is needed to reduce the respective concentration levels of PM and VOCs, that contribute to self-reported health problems.
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Affiliation(s)
- Chrystalla Kaikiti
- Department of Chemistry, University of Cyprus, P.O.Box 20537, 1678, Nicosia, Cyprus
| | - Marinos Stylianou
- Department of Chemistry, University of Cyprus, P.O.Box 20537, 1678, Nicosia, Cyprus
| | - Agapios Agapiou
- Department of Chemistry, University of Cyprus, P.O.Box 20537, 1678, Nicosia, Cyprus.
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Abstract
The past 60 years have seen large reductions in vehicle emissions of particulate matter (PM), nitrogen oxides (NOx), carbon monoxide (CO), hydrocarbons (HCs), sulfur dioxide (SO2), and lead (Pb). Advanced emission after-treatment technologies have been developed for gasoline and diesel vehicles to meet increasingly stringent regulations, yielding absolute emission reductions from the on-road fleet despite increased vehicle miles traveled. As a result of reduced emissions from vehicles and other sources, the air quality in cities across the U.S. and Europe has improved greatly. Turn-over of the on-road fleet, increasingly stringent emission regulations (such as Tier 3 in the U.S., LEV III in California, Euro 6 in Europe, and upcoming rules in these same regions), and the large-scale introduction of electric vehicles will lead to even lower vehicle emissions and further improvements in air quality. We review historical vehicle emissions and air quality trends and discuss the future outlook.
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28
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Bessagnet B, Allemand N, Putaud JP, Couvidat F, André JM, Simpson D, Pisoni E, Murphy BN, Thunis P. Emissions of Carbonaceous Particulate Matter and Ultrafine Particles from Vehicles—A Scientific Review in a Cross-Cutting Context of Air Pollution and Climate Change. APPLIED SCIENCES-BASEL 2022; 12:1-52. [PMID: 35529678 PMCID: PMC9067409 DOI: 10.3390/app12073623] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Airborne particulate matter (PM) is a pollutant of concern not only because of its adverse effects on human health but also on visibility and the radiative budget of the atmosphere. PM can be considered as a sum of solid/liquid species covering a wide range of particle sizes with diverse chemical composition. Organic aerosols may be emitted (primary organic aerosols, POA), or formed in the atmosphere following reaction of volatile organic compounds (secondary organic aerosols, SOA), but some of these compounds may partition between the gas and aerosol phases depending upon ambient conditions. This review focuses on carbonaceous PM and gaseous precursors emitted by road traffic, including ultrafine particles (UFP) and polycyclic aromatic hydrocarbons (PAHs) that are clearly linked to the evolution and formation of carbonaceous species. Clearly, the solid fraction of PM has been reduced during the last two decades, with the implementation of after-treatment systems abating approximately 99% of primary solid particle mass concentrations. However, the role of brown carbon and its radiative effect on climate and the generation of ultrafine particles by nucleation of organic vapour during the dilution of the exhaust remain unclear phenomena and will need further investigation. The increasing role of gasoline vehicles on carbonaceous particle emissions and formation is also highlighted, particularly through the chemical and thermodynamic evolution of organic gases and their propensity to produce particles. The remaining carbon-containing particles from brakes, tyres and road wear will still be a problem even in a future of full electrification of the vehicle fleet. Some key conclusions and recommendations are also proposed to support the decision makers in view of the next regulations on vehicle emissions worldwide.
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Affiliation(s)
- Bertrand Bessagnet
- Joint Research Centre, European Commission, 21027 Ispra, Italy
- Correspondence: or
| | | | | | - Florian Couvidat
- INERIS, Parc Technologique Alata, BP 2, 60550 Verneuil-en-Halatte, France
| | | | - David Simpson
- EMEP MSC-W, Norwegian Meteorological Institute, 0313 Oslo, Norway
- Department Space, Earth & Environment, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
| | - Enrico Pisoni
- Joint Research Centre, European Commission, 21027 Ispra, Italy
| | - Benjamin N. Murphy
- Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, Durham, NC 27711, USA
| | - Philippe Thunis
- Joint Research Centre, European Commission, 21027 Ispra, Italy
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29
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Hurley JF, Smiley E, Isaacman-VanWertz G. Modeled Emission of Hydroxyl and Ozone Reactivity from Evaporation of Fragrance Mixtures. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:15672-15679. [PMID: 34784200 DOI: 10.1021/acs.est.1c04004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Volatile chemical products (VCPs) account for increasing fractions of organic carbon emitted to the atmosphere, particularly in urban areas. Fragrances are potentially reactive components that are added to many VCPs. To better constrain these emissions, 11 commercially available liquid fragrance mixtures were characterized for their composition and their evaporation modeled. Emissions of mass, hydroxyl reactivity, and ozone reactivity were estimated by modeling under four different scenarios. Fragrance compounds were generally less than one-half the mass of fragrance mixtures, with the balance comprised of solvents and plasticizers and unresolved mass thought to be dominated by plasticizers. The results showed that terpenes and terpenoids account for nearly all of the emitted mass and reactivity while only comprising ∼10% w/w on average of the liquid fragrance mixtures. Most of the reactivity is emitted within hours, with ozone reactivity evolving more rapidly than OH reactivity and comprised almost entirely of terpenes. Limonene, a common fragrance constituent, dominates the reactivity of emitted carbon. Generally, 20-40% of the potential hydroxyl reactivity contained in the fragrance mixture does not evaporate on time scales sufficient to have an impact on local or regional air quality.
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Affiliation(s)
- James F Hurley
- Charles E. Via, Jr. Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Elizabeth Smiley
- Charles E. Via, Jr. Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Gabriel Isaacman-VanWertz
- Charles E. Via, Jr. Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
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Sankhyan S, Patel S, Katz EF, DeCarlo PF, Farmer DK, Nazaroff WW, Vance ME. Indoor black carbon and brown carbon concentrations from cooking and outdoor penetration: insights from the HOMEChem study. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2021; 23:1476-1487. [PMID: 34523653 DOI: 10.1039/d1em00283j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Particle emissions from cooking are a major contributor to residential indoor air pollution and could also contribute to ambient concentrations. An important constituent of these emissions is light-absorbing carbon, including black carbon (BC) and brown carbon (BrC). This work characterizes the contributions of indoor and outdoor sources of BC and BrC to the indoor environment by concurrently measuring real-time concentrations of these air pollutants indoors and outdoors during the month-long HOMEChem study. The median indoor-to-outdoor ratios of BC and BrC during the periods of no activity inside the test house were 0.6 and 0.7, respectively. The absorption Ångström exponent was used to characterize light-absorbing particle emissions during different activities and ranged from 1.1 to 2.7 throughout the campaign, with the highest value (indicative of BrC-dominated emissions) observed during the preparation of a simulated Thanksgiving Day holiday style meal. An indoor BC exposure assessment shows that exposure for an occupant present in the kitchen area was ∼4 times higher during Thanksgiving Day experiments (primarily due to candle burning) when compared to the background conditions.
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Affiliation(s)
- Sumit Sankhyan
- Department of Mechanical Engineering, University of Colorado Boulder, 1111 Engineering Drive, 427 UCB, Boulder, CO 80309, USA.
| | - Sameer Patel
- Department of Mechanical Engineering, University of Colorado Boulder, 1111 Engineering Drive, 427 UCB, Boulder, CO 80309, USA.
| | - Erin F Katz
- Department of Chemistry, University of California at Berkeley, 419 Latimer Hall, Berkeley, CA 94720, USA
- Department of Environmental Science, Policy, and Management, University of California at Berkeley, 130 Hilgard Way, Berkeley, CA 94720, USA
| | - Peter F DeCarlo
- Department of Environmental Health and Engineering, Johns Hopkins University, 3400 N Charles St., Baltimore, MD 21218, USA
| | - Delphine K Farmer
- Department of Chemistry, Colorado State University, 200 W Lake St., Fort Collins, CO 80523, USA
| | - William W Nazaroff
- Department of Civil and Environmental Engineering, University of California at Berkeley, 760 Davis Hall, Berkeley, CA 94720, USA
| | - Marina E Vance
- Department of Mechanical Engineering, University of Colorado Boulder, 1111 Engineering Drive, 427 UCB, Boulder, CO 80309, USA.
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Sheu R, Fortenberry CF, Walker MJ, Eftekhari A, Stönner C, Bakker A, Peccia J, Williams J, Morrison GC, Williams BJ, Gentner DR. Evaluating Indoor Air Chemical Diversity, Indoor-to-Outdoor Emissions, and Surface Reservoirs Using High-Resolution Mass Spectrometry. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:10255-10267. [PMID: 34270218 PMCID: PMC8461992 DOI: 10.1021/acs.est.1c01337] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Detailed offline speciation of gas- and particle-phase organic compounds was conducted using gas/liquid chromatography with traditional and high-resolution mass spectrometers in a hybrid targeted/nontargeted analysis. Observations were focused on an unoccupied home and were compared to two other indoor sites. Observed gas-phase organic compounds span the volatile to semivolatile range, while functionalized organic aerosols extend from intermediate volatility to ultra-low volatility, including a mix of oxygen, nitrogen, and sulfur-containing species. Total gas-phase abundances of hydrocarbon and oxygenated gas-phase complex mixtures were elevated indoors and strongly correlated in the unoccupied home. While gas-phase concentrations of individual compounds generally decreased slightly with greater ventilation, their elevated ratios relative to controlled emissions of tracer species suggest that the dilution of gas-phase concentrations increases off-gassing from surfaces and other indoor reservoirs, with volatility-dependent responses to dynamically changing environmental factors. Indoor-outdoor emissions of gas-phase intermediate-volatility/semivolatile organic hydrocarbons from the unoccupied home averaged 6-11 mg h-1, doubling with ventilation. While the largest single-compound emissions observed were furfural (61-275 mg h-1) and acetic acid, observations spanned a wide range of individual volatile chemical products (e.g., terpenoids, glycol ethers, phthalates, other oxygenates), highlighting the abundance of long-lived reservoirs resulting from prior indoor use or materials, and their gradual transport outdoors.
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Affiliation(s)
- Roger Sheu
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06511, United States
| | - Claire F Fortenberry
- Department of Energy, Environmental, & Chemical Engineering and Center for Aerosol Science and Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Michael J Walker
- Department of Energy, Environmental, & Chemical Engineering and Center for Aerosol Science and Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Azin Eftekhari
- Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27515, United States
| | - Christof Stönner
- Department of Atmospheric Chemistry, Max Planck Institute for Chemistry, Mainz 55128, Germany
| | - Alexa Bakker
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06511, United States
| | - Jordan Peccia
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06511, United States
| | - Jonathan Williams
- Department of Atmospheric Chemistry, Max Planck Institute for Chemistry, Mainz 55128, Germany
| | - Glenn C Morrison
- Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27515, United States
| | - Brent J Williams
- Department of Energy, Environmental, & Chemical Engineering and Center for Aerosol Science and Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Drew R Gentner
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06511, United States
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