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Li C, Martin RV, van Donkelaar A. Understanding Reductions of PM 2.5 Concentration and Its Chemical Composition in the United States: Implications for Mitigation Strategies. ACS ES&T AIR 2024; 1:637-645. [PMID: 39021669 PMCID: PMC11251419 DOI: 10.1021/acsestair.4c00004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 04/30/2024] [Accepted: 05/01/2024] [Indexed: 07/20/2024]
Abstract
Motivated by the recent tightening of the US annual standard of fine particulate matter (PM2.5) concentrations from 12 to 9 μg/m3, there is a need to understand the spatial variation and drivers of historical PM2.5 reductions. We evaluate and interpret the variability of PM2.5 reductions across the contiguous US using high-resolution estimates of PM2.5 and its chemical composition over 1998-2019, inferred from satellite observations, air quality modeling, and ground-based measurements. We separated the 3092 counties into four characteristic regions sorted by PM2.5 trends. Region 1 (primarily Central Atlantic states, 25.9% population) exhibits the strongest population-weighted annual PM2.5 reduction (-3.6 ± 0.4%/yr) versus Region 2 (primarily rest of the eastern US, -3.0 ± 0.3%/yr, 39.7% population), Region 3 (primarily western Midwest, -1.9 ± 0.3%/yr, 25.6% population), and Region 4 (primarily the Mountain West, -0.4 ± 0.5%/yr, 8.9% population). Decomposition of these changes by chemical composition elucidates that sulfate exhibits the fastest reductions among all components in 2720 counties (76% of population), mostly over Regions 1-3, with the 1998-2019 mean sulfate mass fraction in PM2.5 decreasing from Region 1 (29.5%) to Region 4 (11.8%). Complete elimination of the remaining sulfate may be insufficient to meet the new standard for many regions in exceedance. Additional measures are needed to reduce other PM2.5 sources and components for further progress.
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Affiliation(s)
- Chi Li
- Department of Energy, Environmental
& Chemical Engineering, Washington University
in St. Louis, St. Louis, Missouri 63130, United States
| | - Randall V. Martin
- Department of Energy, Environmental
& Chemical Engineering, Washington University
in St. Louis, St. Louis, Missouri 63130, United States
| | - Aaron van Donkelaar
- Department of Energy, Environmental
& Chemical Engineering, Washington University
in St. Louis, St. Louis, Missouri 63130, United States
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2
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Chen Q, Miao R, Geng G, Shrivastava M, Dao X, Xu B, Sun J, Zhang X, Liu M, Tang G, Tang Q, Hu H, Huang RJ, Wang H, Zheng Y, Qin Y, Guo S, Hu M, Zhu T. Widespread 2013-2020 decreases and reduction challenges of organic aerosol in China. Nat Commun 2024; 15:4465. [PMID: 38796477 PMCID: PMC11127919 DOI: 10.1038/s41467-024-48902-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 05/17/2024] [Indexed: 05/28/2024] Open
Abstract
High concentrations of organic aerosol (OA) occur in Asian countries, leading to great health burdens. Clean air actions have resulted in significant emission reductions of air pollutants in China. However, long-term nation-wide trends in OA and their causes remain unknown. Here, we present both observational and model evidence demonstrating widespread decreases with a greater reduction in primary OA than in secondary OA (SOA) in China during the period of 2013 to 2020. Most of the decline is attributed to reduced residential fuel burning while the interannual variability in SOA may have been driven by meteorological variations. We find contrasting effects of reducing NOx and SO2 on SOA production which may have led to slight overall increases in SOA. Our findings highlight the importance of clean energy replacements in multiple sectors on achieving air-quality targets because of high OA precursor emissions and fluctuating chemical and meteorological conditions.
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Affiliation(s)
- Qi Chen
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, Beijing Innovation Center for Engineering Science and Advanced Technology, International Joint Laboratory for Regional Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China.
- Institute of Carbon Neutrality, Peking University, Beijing, China.
| | - Ruqian Miao
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, Beijing Innovation Center for Engineering Science and Advanced Technology, International Joint Laboratory for Regional Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China
| | - Guannan Geng
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China
| | | | - Xu Dao
- China National Environmental Monitoring Centre, Beijing, China
| | - Bingye Xu
- Zhejiang Key Laboratory of Ecological and Environmental Monitoring, Forewarning and Quality Control, Zhejiang Province Environment Monitoring Centre, Hangzhou, China
| | - Jiaqi Sun
- China National Environmental Monitoring Centre, Beijing, China
| | - Xian Zhang
- China National Environmental Monitoring Centre, Beijing, China
| | - Mingyuan Liu
- China National Environmental Monitoring Centre, Beijing, China
| | - Guigang Tang
- China National Environmental Monitoring Centre, Beijing, China
| | - Qian Tang
- Zhejiang Key Laboratory of Ecological and Environmental Monitoring, Forewarning and Quality Control, Zhejiang Province Environment Monitoring Centre, Hangzhou, China
| | - Hanwen Hu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China
| | - Ru-Jin Huang
- State Key Laboratory of Loess and Quaternary Geology, Center for Excellence in Quaternary Science and Global Change, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, China
| | - Hao Wang
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, Beijing Innovation Center for Engineering Science and Advanced Technology, International Joint Laboratory for Regional Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China
| | - Yan Zheng
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, Beijing Innovation Center for Engineering Science and Advanced Technology, International Joint Laboratory for Regional Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China
| | - Yue Qin
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, Beijing Innovation Center for Engineering Science and Advanced Technology, International Joint Laboratory for Regional Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China
- Institute of Carbon Neutrality, Peking University, Beijing, China
| | - Song Guo
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, Beijing Innovation Center for Engineering Science and Advanced Technology, International Joint Laboratory for Regional Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China
- Institute of Carbon Neutrality, Peking University, Beijing, China
| | - Min Hu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, Beijing Innovation Center for Engineering Science and Advanced Technology, International Joint Laboratory for Regional Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China
- Institute of Carbon Neutrality, Peking University, Beijing, China
| | - Tong Zhu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, Beijing Innovation Center for Engineering Science and Advanced Technology, International Joint Laboratory for Regional Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China
- Institute of Carbon Neutrality, Peking University, Beijing, China
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3
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Yao PT, Peng X, Cao LM, Zeng LW, Feng N, He LY, Huang XF. Evaluation of a new real-time source apportionment system of PM 2.5 and its implication on rapid aging of vehicle exhaust. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 937:173449. [PMID: 38797425 DOI: 10.1016/j.scitotenv.2024.173449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2024] [Revised: 05/07/2024] [Accepted: 05/20/2024] [Indexed: 05/29/2024]
Abstract
Accurate identification and rapid analysis of PM2.5 sources and formation mechanisms are essential to mitigate PM2.5 pollution. However, studies were limited in developing a method to apportion sources to the total PM2.5 mass in real-time. In this study, we developed a real-time source apportionment method based on chemical mass balance (CMB) modeling and a mass-closure PM2.5 composition online monitoring system in Shenzhen, China. Results showed that secondary sulfate, secondary organic aerosol (SOA), vehicle emissions and secondary nitrate were the four major PM2.5 sources during autumn 2019 in Shenzhen, together contributed 76 % of PM2.5 mass. The novel method was verified by comparing with other source apportionment methods, including offline filter analysis, aerosol mass spectrometry, and carbon isotopic analysis. The comparison of these methods showed that the new real-time method obtained results generally consistent with the others, and the differences were interpretable and implicative. SOA and vehicle emissions were the major PM2.5 and OA contributors by all methods. Further investigation on the OA sources indicated that vehicle emissions were not only the main source of primary organic aerosol (POA), but also the main contributor to SOA by rapid aging of the exhaust in the atmosphere. Our results demonstrated the great potential of the new real-time source apportionment method for aerosol pollution control and deep understandings on emission sources.
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Affiliation(s)
- Pei-Ting Yao
- Laboratory of Atmospheric Observation Supersite, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Xing Peng
- Laboratory of Atmospheric Observation Supersite, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China.
| | - Li-Ming Cao
- Laboratory of Atmospheric Observation Supersite, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Li-Wu Zeng
- Laboratory of Atmospheric Observation Supersite, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Ning Feng
- Laboratory of Atmospheric Observation Supersite, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Ling-Yan He
- Laboratory of Atmospheric Observation Supersite, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Xiao-Feng Huang
- Laboratory of Atmospheric Observation Supersite, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China.
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4
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Zhang G, Chen Z, Li J, Su B, Gao Y, Yu L. Quantifying US air pollution policy: How political and regional factors influence pollutant mitigation. PNAS NEXUS 2024; 3:pgae199. [PMID: 38818239 PMCID: PMC11138116 DOI: 10.1093/pnasnexus/pgae199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2023] [Accepted: 05/09/2024] [Indexed: 06/01/2024]
Abstract
Air pollution control in the United States has evolved into a comprehensive policy system spanning from the federal to the state level over time. A unified quantitative analysis of policy intensity can shed light on the policy evolution across different levels, the influence of partisan and regional factors on policy, and the relationships with emissions of major pollutants. By harnessing the policy text of the Clean Air Act (CAA) at the federal level and State Implementation Plans (SIPs) at the state governments (1955-2020), we deployed a Natural Language Processing approach to define a policy intensity index to systematically quantify the US air policy landscape. Our findings highlight that the 1970 CAA amendment carries the most vigorous intensity as it established a holistic control system for the first time. Subsequent years witnessed a general trend of partisan polarization, eventually leading to a graduate convergence between red and blue states. Blue states demonstrated a closer alignment with federal directives and a superior efficacy in pollutant reduction. Regionally, the Northeast displays the highest overall policy intensity, and the West exhibits the highest coordination with the federal benchmarks, making these regions outperform others in air pollution control. Our study not only discusses policy implications for air pollutant reductions considering partisan and regional differences but also provides a novel measurement tool to quantify policies for assessing disparities and synergies.
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Affiliation(s)
- Guoxing Zhang
- School of Management, Lanzhou University, Lanzhou 730000, China
| | - Zhanglei Chen
- School of Management, Lanzhou University, Lanzhou 730000, China
| | - Jiexun Li
- Department of Decision Sciences, Western Washington University, Bellingham, WA 98225, USA
| | - Bin Su
- Energy Studies Institute, National University of Singapore, 119620, Singapore, Singapore
- Department of Industrial Systems Engineering and Management, National University of Singapore, 117576, Singapore, Singapore
| | - Yang Gao
- School of Management, Lanzhou University, Lanzhou 730000, China
| | - Lean Yu
- Business School, Sichuan University, Chengdu 610065, China
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5
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O'Dell K, Kondragunta S, Zhang H, Goldberg DL, Kerr GH, Wei Z, Henderson BH, Anenberg SC. Public Health Benefits From Improved Identification of Severe Air Pollution Events With Geostationary Satellite Data. GEOHEALTH 2024; 8:e2023GH000890. [PMID: 38259818 PMCID: PMC10801669 DOI: 10.1029/2023gh000890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 10/01/2023] [Accepted: 10/06/2023] [Indexed: 01/24/2024]
Abstract
Despite improvements in ambient air quality in the US in recent decades, many people still experience unhealthy levels of pollution. At present, national-level alert-day identification relies predominately on surface monitor networks and forecasters. Satellite-based estimates of surface air quality have rapidly advanced and have the capability to inform exposure-reducing actions to protect public health. At present, we lack a robust framework to quantify public health benefits of these advances in applications of satellite-based atmospheric composition data. Here, we assess possible health benefits of using geostationary satellite data, over polar orbiting satellite data, for identifying particulate air quality alert days (24hr PM2.5 > 35 μg m-3) in 2020. We find the more extensive spatiotemporal coverage of geostationary satellite data leads to a 60% increase in identification of person-alerts (alert days × population) in 2020 over polar-orbiting satellite data. We apply pre-existing estimates of PM2.5 exposure reduction by individual behavior modification and find these additional person-alerts may lead to 1,200 (800-1,500) or 54% more averted PM2.5-attributable premature deaths per year, if geostationary, instead of polar orbiting, satellite data alone are used to identify alert days. These health benefits have an associated economic value of 13 (8.8-17) billion dollars ($2019) per year. Our results highlight one of many potential applications of atmospheric composition data from geostationary satellites for improving public health. Identifying these applications has important implications for guiding use of current satellite data and planning future geostationary satellite missions.
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Affiliation(s)
- Katelyn O'Dell
- Milken Institute School of Public HealthGeorge Washington UniversityWashingtonDCUSA
| | - Shobha Kondragunta
- NOAA/NESDIS/Center for Satellite Applications and ResearchCollege ParkMDUSA
| | - Hai Zhang
- I. M. Systems Group, NOAA NCWCP, 5830 University Research CtCollege ParkMDUSA
| | - Daniel L. Goldberg
- Milken Institute School of Public HealthGeorge Washington UniversityWashingtonDCUSA
| | - Gaige Hunter Kerr
- Milken Institute School of Public HealthGeorge Washington UniversityWashingtonDCUSA
| | - Zigang Wei
- I. M. Systems Group, NOAA NCWCP, 5830 University Research CtCollege ParkMDUSA
| | | | - Susan C. Anenberg
- Milken Institute School of Public HealthGeorge Washington UniversityWashingtonDCUSA
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6
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Déméautis T, Bouyssi A, Chapalain A, Guillemot J, Doublet P, Geloen A, George C, Menotti J, Glehen O, Devouassoux G, Bentaher A. Chronic Exposure to Secondary Organic Aerosols Causes Lung Tissue Damage. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:6085-6094. [PMID: 37014236 DOI: 10.1021/acs.est.2c08753] [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: 06/19/2023]
Abstract
Recently, secondary organic aerosols (SOAs) emerged as a predominant component of fine particulate matter. However, the pathogenic mechanism(s) of SOAs are still poorly understood. Herein, we show that chronic exposure of mice to SOAs resulted in lung inflammation and tissue destruction. Histological analyses found lung airspace enlargement associated with massive inflammatory cell recruitment predominated by macrophages. Concomitant with such cell influx, our results found changes in the levels of a series of inflammatory mediators in response to SOA. Interestingly, we observed that the expression of the genes encoding for TNF-α and IL-6 increased significantly after one month of exposure to SOAs; mediators that have been largely documented to play a role in chronic pulmonary inflammatory pathologies. Cell culture studies confirmed these in vivo findings. Of importance as well, our study indicates increased matrix metalloproteinase proteolytic activity suggesting its contribution to lung tissue inflammation and degradation. Our work represents the first in vivo study, which reports that chronic exposure to SOAs leads to lung inflammation and tissue injury. Thus, we hope that these data will foster new studies to enhance our understanding of the underlying pathogenic mechanisms of SOAs and perhaps help in the design of therapeutic strategies against SOA-mediated lung injury.
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Affiliation(s)
- Tanguy Déméautis
- Inflammation and Immunity of the Respiratory Epithelium - EA3738 (CICLY) - South Medical University Hospital, Lyon 1 Claude Bernard University, 165 Chemin du grand Revoyet, 69395 Pierre-Bénite, France
| | - Alexandra Bouyssi
- Inflammation and Immunity of the Respiratory Epithelium - EA3738 (CICLY) - South Medical University Hospital, Lyon 1 Claude Bernard University, 165 Chemin du grand Revoyet, 69395 Pierre-Bénite, France
| | - Annelise Chapalain
- CIRI, Centre International de Recherche en Infectiologie, Team Legionella Pathogenesis, Univ Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, F-69007 Lyon, France
| | - Johann Guillemot
- CIRI, Centre International de Recherche en Infectiologie, Team Legionella Pathogenesis, Univ Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, F-69007 Lyon, France
| | - Patricia Doublet
- CIRI, Centre International de Recherche en Infectiologie, Team Legionella Pathogenesis, Univ Lyon, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de Lyon, F-69007 Lyon, France
| | - Alain Geloen
- University of Lyon, UMR Ecologie Microbienne Lyon (LEM), CNRS 5557, INRAE 1418, Université Claude Bernard Lyon 1, VetAgro Sup, Research Team "Bacterial Opportunistic Pathogens and Environment" (BPOE), 69622 Villeurbanne, France
| | - Christian George
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, 2 Avenue Albert Einstein, 69626 Villeurbanne, France
| | - Jean Menotti
- Inflammation and Immunity of the Respiratory Epithelium - EA3738 (CICLY) - South Medical University Hospital, Lyon 1 Claude Bernard University, 165 Chemin du grand Revoyet, 69395 Pierre-Bénite, France
| | - Olivier Glehen
- Inflammation and Immunity of the Respiratory Epithelium - EA3738 (CICLY) - South Medical University Hospital, Lyon 1 Claude Bernard University, 165 Chemin du grand Revoyet, 69395 Pierre-Bénite, France
- Service de chirurgie digestive et endocrinienne, CHU de Lyon HCL - GH Sud, 165 Chemin du Grand Revoyet, 69495 Pierre-Benite, France
| | - Gilles Devouassoux
- Inflammation and Immunity of the Respiratory Epithelium - EA3738 (CICLY) - South Medical University Hospital, Lyon 1 Claude Bernard University, 165 Chemin du grand Revoyet, 69395 Pierre-Bénite, France
- Service de Pneumologie, Hôpital de la Croix Rousse, Hospices Civils de Lyon, UCB Lyon 1, 103 Grande Rue de la Croix-Rousse, 69004 Lyon, France
| | - Abderrazzak Bentaher
- Inflammation and Immunity of the Respiratory Epithelium - EA3738 (CICLY) - South Medical University Hospital, Lyon 1 Claude Bernard University, 165 Chemin du grand Revoyet, 69395 Pierre-Bénite, France
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7
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Oak YJ, Park RJ, Lee JT, Byun G. Future air quality and premature mortality in Korea. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 865:161134. [PMID: 36587681 DOI: 10.1016/j.scitotenv.2022.161134] [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: 10/11/2022] [Revised: 11/22/2022] [Accepted: 12/19/2022] [Indexed: 06/17/2023]
Abstract
We simulate air quality in Korea for the present, the near-term, and the long-term future conditions under the Shared Socioeconomic Pathways (SSP1: most sustainable pathway with strong emissions control, SSP3: most challenging pathway with mild emissions control) using a chemical transport model. Simulated future concentrations of NO2, SO2, and fine particulate matter (PM2.5), show, in general, lower values compared to the present with varying degrees depending on SSP scenarios. Significant reductions in precursor emissions result in a decrease in O3 concentrations under a NOx-limited environment in the long-term future under SSP1. Under SSP3, O3 increases in the future under a VOC-limited regime, driven by increased CH4 levels and biogenic VOC emissions under the warming climate. Concentrations of PM2.5 and its components, including sulfate, nitrate, ammonium, and organic aerosols (OA), generally decrease in the long-term future under both scenarios. However, the contribution of biogenic secondary OA (BSOA) to PM2.5 will increase in the future. Simulated results are used to estimate cardiorespiratory mortality changes with concentration-response factors from epidemiologic studies in Korea based on national health surveys and Korean cohorts, using projected population structures from the SSP database. The cardiorespiratory health burden of long-term exposure to O3, NO2, SO2, and PM2.5 is estimated to be 10,419 (95 % confidence interval: 1271-17,142), 8630 (0-18,713), 3958 (0-9272), and 10,431 (1411-20,643) deaths in 2019. We find that the total cardiorespiratory excess mortality due to air pollutants under SSP1 decreases by 8 % and 95 % in 2045 and 2095, respectively. Under SSP3, excess mortality increases by 80 % in 2045, and decreases by 22 % in 2095, resulting in a substantial difference in the health outcomes depending on the emission scenario. We also find that the BSOA contribution to total PM2.5 will differ by region, emphasizing the potential health impact of BSOA on a local scale in the future.
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Affiliation(s)
- Yujin J Oak
- School of Earth and Environmental Sciences, Seoul National University, Seoul, South Korea
| | - Rokjin J Park
- School of Earth and Environmental Sciences, Seoul National University, Seoul, South Korea.
| | - Jong-Tae Lee
- School of Health Policy and Management, College of Health Science, Korea University, Seoul, South Korea; Interdisciplinary Program in Precision Public Health, Korea University, Seoul, South Korea
| | - Garam Byun
- Interdisciplinary Program in Precision Public Health, Korea University, Seoul, South Korea
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8
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Zhao Y, Tkacik DS, May AA, Donahue NM, Robinson AL. Mobile Sources Are Still an Important Source of Secondary Organic Aerosol and Fine Particulate Matter in the Los Angeles Region. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:15328-15336. [PMID: 36215417 DOI: 10.1021/acs.est.2c03317] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Secondary organic aerosol (SOA) is a significant component of atmospheric fine particulate matter. Mobile sources have historically been a major source of SOA precursors in urban environments, but decades of regulations have reduced their emissions. Less regulated sources, such as volatile chemical products (VCPs), are of growing importance. We analyzed ambient and emissions data to assess the contribution of mobile sources to SOA formation in Los Angeles during the period of 2009-2019. During this period, air quality in the Los Angeles region has improved, but organic aerosol (OA) concentrations did not decrease as much as primary pollutants. This appears to be largely due to SOA, whose mass fraction in OA increased over this period. In 2010, about half of the freshly formed SOA measured in Pasadena, CA appears to be formed from hydrocarbon (non-oxygenated) precursors. Chemical mass balance analysis indicates that these hydrocarbon SOA precursors (including intermediate volatility organic compounds) can largely be explained by emissions from mobile sources in 2010. Our analysis indicates that continued reduction in emissions from mobile sources should lead to additional significant decreases in atmospheric SOA and PM2.5 mass in the Los Angeles region.
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Affiliation(s)
- Yunliang Zhao
- Center for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Daniel S Tkacik
- Center for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
- Department of Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Andrew A May
- Center for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Neil M Donahue
- Center for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
- Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Allen L Robinson
- Center for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
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9
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Déméautis T, Delles M, Tomaz S, Monneret G, Glehen O, Devouassoux G, George C, Bentaher A. Pathogenic Mechanisms of Secondary Organic Aerosols. Chem Res Toxicol 2022; 35:1146-1161. [PMID: 35737464 DOI: 10.1021/acs.chemrestox.1c00353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Air pollution represents a major health problem and an economic burden. In recent years, advances in air pollution research has allowed particle fractionation and identification of secondary organic aerosol (SOA). SOA is formed from either biogenic or anthropogenic emissions, through a mass transfer from the gaseous mass to the particulate phase in the atmosphere. They can have deleterious impact on health and the mortality of individuals with chronic inflammatory diseases. The pleiotropic effects of SOA could involve different and interconnected pathogenic mechanisms ranging from oxidative stress, inflammation, and immune system dysfunction. The purpose of this review is to present recent findings about SOA pathogenic roles and potential underlying mechanisms focusing on the lungs; the latter being the primary exposed organ to atmospheric pollutants.
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Affiliation(s)
- Tanguy Déméautis
- Inflammation and Immunity of the Respiratory Epithelium, EA3738 (CICLY), South Medical University Hospital, Lyon 1 Claude Bernard University, 165 Chemin du grand Revoyet, 69395 Pierre-Bénite, France
| | - Marie Delles
- Inflammation and Immunity of the Respiratory Epithelium, EA3738 (CICLY), South Medical University Hospital, Lyon 1 Claude Bernard University, 165 Chemin du grand Revoyet, 69395 Pierre-Bénite, France
| | - Sophie Tomaz
- University of Lyon, Lyon 1 Claude Bernard University, CNRS, IRCELYON, 2 Avenue Albert Einstein, 69626 Villeurbanne, France
| | - Guillaume Monneret
- Pathophysiology of Immunosuppression Associated with Systemic Inflammatory Responses, EA7426 (PI3), Edouard Herriot Hospital, 5 Place d'Arsonval, 69003 Lyon, France
| | - Olivier Glehen
- Inflammation and Immunity of the Respiratory Epithelium, EA3738 (CICLY), South Medical University Hospital, Lyon 1 Claude Bernard University, 165 Chemin du grand Revoyet, 69395 Pierre-Bénite, France.,Digestive and Endocrine Surgery Department, University Hospital of Lyon, Lyon South Hospital,165 Chemin du Grand Revoyet 69495 Pierre-Benite, France
| | - Gilles Devouassoux
- Inflammation and Immunity of the Respiratory Epithelium, EA3738 (CICLY), South Medical University Hospital, Lyon 1 Claude Bernard University, 165 Chemin du grand Revoyet, 69395 Pierre-Bénite, France.,Pulmonology Department, Croix Rousse Hospital, Lyon Civil Hospices, Lyon 1 Claude Bernard University, 103 Grande Rue de la Croix-Rousse, 69004 Lyon, France
| | - Christian George
- University of Lyon, Lyon 1 Claude Bernard University, CNRS, IRCELYON, 2 Avenue Albert Einstein, 69626 Villeurbanne, France
| | - Abderrazzak Bentaher
- Inflammation and Immunity of the Respiratory Epithelium, EA3738 (CICLY), South Medical University Hospital, Lyon 1 Claude Bernard University, 165 Chemin du grand Revoyet, 69395 Pierre-Bénite, France
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10
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Wang H, Zhang L, Yao X, Cheng I, Dabek-Zlotorzynska E. Identification of decadal trends and associated causes for organic and elemental carbon in PM 2.5 at Canadian urban sites. ENVIRONMENT INTERNATIONAL 2022; 159:107031. [PMID: 34890898 DOI: 10.1016/j.envint.2021.107031] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Revised: 11/23/2021] [Accepted: 12/03/2021] [Indexed: 06/13/2023]
Abstract
Chemically resolved data for fine particulate matter (PM2.5) have been collected across Canada since 2003 through the National Air Pollution Surveillance (NAPS) network. Seven urban sites that have 10-17 years (2003-2019) of PM2.5 organic carbon (OC) and elemental carbon (EC) data were selected for analysis of decadal trends of OC, EC, and OC/EC ratio using the Ensemble Empirical Mode Decomposition method. Results showed that OC and EC decreased by 0.009-0.072 μg m-3 yr-1 and 0.028-0.049 μg m-3 yr-1, or 0.77-3.1 % yr-1 and 3.2-6.7 % yr-1, respectively, depending on the location. The more rapid decrease in EC than OC resulted in an increasing trend in the OC/EC ratio of 0.03-0.19 yr-1 across the sites. Macro-tracer approach was used to estimate source attributions of OC and EC from wood burning, fossil fuel combustion, and secondary aerosol formation. Using this approach, it was identified that the significant decrease in EC during the past decade was predominately caused by reduced on-road emissions. The decreased emissions from wood burning and transportation dominated the decline of OC, but such a decline was largely offset by the enhanced secondary organic aerosol (SOA) formation, resulting in much weaker decline of OC than EC. The enhanced SOA formation was due to the increased biogenic emissions fully offsetting the decreased anthropogenic emissions for volatile organic compounds. These findings highlight the need for quantifying biogenic sources of VOCs and other oxidants that are involved in OC formation at the national scale.
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Affiliation(s)
- Huanbo Wang
- School of Environment and Resource, Southwest University of Science and Technology, Mianyang, China
| | - Leiming Zhang
- Air Quality Research Division, Science and Technology Branch, Environment and Climate Change Canada, Toronto, Canada.
| | - Xiaohong Yao
- Lab of Marine Environmental Science and Ecology, Ministry of Education, Ocean University of China, Qingdao, China
| | - Irene Cheng
- Air Quality Research Division, Science and Technology Branch, Environment and Climate Change Canada, Toronto, Canada
| | - Ewa Dabek-Zlotorzynska
- Air Quality Research Division, Science and Technology Branch, Environment and Climate Change Canada, Ottawa, Canada
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Particulate Matter-Induced Acute Coronary Syndrome: MicroRNAs as Microregulators for Inflammatory Factors. Mediators Inflamm 2021; 2021:6609143. [PMID: 34931116 PMCID: PMC8684514 DOI: 10.1155/2021/6609143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Accepted: 11/18/2021] [Indexed: 12/03/2022] Open
Abstract
The most prevalent cause of mortality and morbidity worldwide is acute coronary syndrome (ACS) and its consequences. Exposure to particulate matter (PM) from air pollution has been shown to impair both. Various plausible pathogenic mechanisms have been identified, including microRNAs (miRNAs), an epigenetic regulator for gene expression. Endogenous miRNAs, average 22-nucleotide RNAs (ribonucleic acid), regulate gene expression through mRNA cleavage or translation repression and can influence proinflammatory gene expression posttranscriptionally. However, little is known about miRNA responses to fine PM (PM2.5, PM10, ultrafine particles, black carbon, and polycyclic aromatic hydrocarbon) from air pollution and their potential contribution to cardiovascular consequences, including systemic inflammation regulation. For the past decades, microRNAs (miRNAs) have emerged as novel, prospective diagnostic and prognostic biomarkers in various illnesses, including ACS. We wanted to outline some of the most important studies in the field and address the possible utility of miRNAs in regulating particulate matter-induced ACS (PMIA) on inflammatory factors in this review.
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van Donkelaar A, Hammer MS, Bindle L, Brauer M, Brook JR, Garay MJ, Hsu NC, Kalashnikova OV, Kahn RA, Lee C, Levy RC, Lyapustin A, Sayer AM, Martin RV. Monthly Global Estimates of Fine Particulate Matter and Their Uncertainty. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:15287-15300. [PMID: 34724610 DOI: 10.1021/acs.est.1c05309] [Citation(s) in RCA: 142] [Impact Index Per Article: 47.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Annual global satellite-based estimates of fine particulate matter (PM2.5) are widely relied upon for air-quality assessment. Here, we develop and apply a methodology for monthly estimates and uncertainties during the period 1998-2019, which combines satellite retrievals of aerosol optical depth, chemical transport modeling, and ground-based measurements to allow for the characterization of seasonal and episodic exposure, as well as aid air-quality management. Many densely populated regions have their highest PM2.5 concentrations in winter, exceeding summertime concentrations by factors of 1.5-3.0 over Eastern Europe, Western Europe, South Asia, and East Asia. In South Asia, in January, regional population-weighted monthly mean PM2.5 concentrations exceed 90 μg/m3, with local concentrations of approximately 200 μg/m3 for parts of the Indo-Gangetic Plain. In East Asia, monthly mean PM2.5 concentrations have decreased over the period 2010-2019 by 1.6-2.6 μg/m3/year, with decreases beginning 2-3 years earlier in summer than in winter. We find evidence that global-monitored locations tend to be in cleaner regions than global mean PM2.5 exposure, with large measurement gaps in the Global South. Uncertainty estimates exhibit regional consistency with observed differences between ground-based and satellite-derived PM2.5. The evaluation of uncertainty for agglomerated values indicates that hybrid PM2.5 estimates provide precise regional-scale representation, with residual uncertainty inversely proportional to the sample size.
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Affiliation(s)
- Aaron van Donkelaar
- Department of Energy, Environmental, and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
- Department of Physics and Atmospheric Science, Dalhousie University, Halifax, Nova Scotia B3H 3J5, Canada
| | - Melanie S Hammer
- Department of Energy, Environmental, and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Liam Bindle
- Department of Energy, Environmental, and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Michael Brauer
- School of Population and Public Health, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, Washington 98195, United States
| | - Jeffery R Brook
- Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario M5T 1P8, Canada
| | - Michael J Garay
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109, United States
| | - N Christina Hsu
- Earth Sciences Division, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, United States
| | - Olga V Kalashnikova
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109, United States
| | - Ralph A Kahn
- Earth Sciences Division, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, United States
| | - Colin Lee
- Department of Physics and Atmospheric Science, Dalhousie University, Halifax, Nova Scotia B3H 3J5, Canada
| | - Robert C Levy
- Earth Sciences Division, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, United States
| | - Alexei Lyapustin
- Earth Sciences Division, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, United States
| | - Andrew M Sayer
- Earth Sciences Division, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, United States
- Goddard Earth Sciences Technology and Research, Universities Space Research Association, Columbia, Maryland 21046, United States
| | - Randall V Martin
- Department of Energy, Environmental, and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
- Department of Physics and Atmospheric Science, Dalhousie University, Halifax, Nova Scotia B3H 3J5, Canada
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Waidyatillake NT, Campbell PT, Vicendese D, Dharmage SC, Curto A, Stevenson M. Particulate Matter and Premature Mortality: A Bayesian Meta-Analysis. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18147655. [PMID: 34300107 PMCID: PMC8303514 DOI: 10.3390/ijerph18147655] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 07/13/2021] [Accepted: 07/14/2021] [Indexed: 12/25/2022]
Abstract
BACKGROUND We present a systematic review of studies assessing the association between ambient particulate matter (PM) and premature mortality and the results of a Bayesian hierarchical meta-analysis while accounting for population differences of the included studies. METHODS The review protocol was registered in the PROSPERO systematic review registry. Medline, CINAHL and Global Health databases were systematically searched. Bayesian hierarchical meta-analysis was conducted using a non-informative prior to assess whether the regression coefficients differed across observations due to the heterogeneity among studies. RESULTS We identified 3248 records for title and abstract review, of which 309 underwent full text screening. Thirty-six studies were included, based on the inclusion criteria. Most of the studies were from China (n = 14), India (n = 6) and the USA (n = 3). PM2.5 was the most frequently reported pollutant. PM was estimated using modelling techniques (22 studies), satellite-based measures (four studies) and direct measurements (ten studies). Mortality data were sourced from country-specific mortality statistics for 17 studies, Global Burden of Disease data for 16 studies, WHO data for two studies and life tables for one study. Sixteen studies were included in the Bayesian hierarchical meta-analysis. The meta-analysis revealed that the annual estimate of premature mortality attributed to PM2.5 was 253 per 1,000,000 population (95% CI: 90, 643) and 587 per 1,000,000 population (95% CI: 1, 39,746) for PM10. CONCLUSION 253 premature deaths per million population are associated with exposure to ambient PM2.5. We observed an unstable estimate for PM10, most likely due to heterogeneity among the studies. Future research efforts should focus on the effects of ambient PM10 and premature mortality, as well as include populations outside Asia. Key messages: Ambient PM2.5 is associated with premature mortality. Given that rapid urbanization may increase this burden in the coming decades, our study highlights the urgency of implementing air pollution mitigation strategies to reduce the risk to population and planetary health.
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Affiliation(s)
- Nilakshi T. Waidyatillake
- Allergy and Lung Health Unit, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, VIC 3010, Australia; (D.V.); (S.C.D.)
- Department of Medical Education, Melbourne Medical School, The University of Melbourne, Melbourne, VIC 3010, Australia
- Correspondence: (N.T.W.); (M.S.)
| | - Patricia T. Campbell
- Department of Infectious Diseases, Melbourne Medical School, University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, VIC 3000, Australia;
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, VIC 3010, Australia
| | - Don Vicendese
- Allergy and Lung Health Unit, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, VIC 3010, Australia; (D.V.); (S.C.D.)
- Department of Mathematics and Statistics, La Trobe University, Bundoora, VIC 3086, Australia
| | - Shyamali C. Dharmage
- Allergy and Lung Health Unit, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, VIC 3010, Australia; (D.V.); (S.C.D.)
| | - Ariadna Curto
- Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne, VIC 3065, Australia;
| | - Mark Stevenson
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, VIC 3010, Australia
- Transport Health and Urban Design Research Lab, Melbourne School of Design, The University of Melbourne, Melbourne, VIC 3010, Australia
- Correspondence: (N.T.W.); (M.S.)
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14
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Wang H, Zhang L, Cheng I, Yao X, Dabek-Zlotorzynska E. Spatiotemporal trends of PM 2.5 and its major chemical components at urban sites in Canada. J Environ Sci (China) 2021; 103:1-11. [PMID: 33743892 DOI: 10.1016/j.jes.2020.09.035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 09/29/2020] [Accepted: 09/29/2020] [Indexed: 05/22/2023]
Abstract
To evaluate the effectiveness of emission control regulations designed for reducing air pollution, chemically resolved PM2.5 data have been collected across Canada through the National Air Pollution Surveillance network in the past decade. 24-hr time integrated PM2.5 collected at seven urban and two rural sites during 2010-2016 were analyzed to characterize geographical and seasonal patterns and associated potential causes. Site-specific seven-year mean gravimetric PM2.5 mass concentrations ranged from 5.7 to 9.6 µg/m3. Seven-year mean concentrations of SO42-, NO3-, NH4+, organic carbon (OC), and elemental carbon (EC) were in the range of 0.68 to 1.6, 0.21 to 1.5, 0.27 to 0.71, 1.1 to 1.9, and 0.37 to 0.71 µg /m3, accounting for 10.8%-18.1%, 3.7%-16.7%, 4.7%-7.4%, 18.4%-21.0%, and 6.4%-10.6%, respectively, of gravimetric PM2.5 mass. PM2.5 and its five major chemical components showed higher concentrations in southeastern Canada and lower values in Atlantic Canada, with the seven-year mean ratios between the two regions being on the order of 1.7 for PM2.5 and 1.8-7.1 for its chemical components. When comparing the concentrations between urban and rural sites within the same region, those of SO42- and NH4+ were comparable, while those of NO3-, OC, and EC were around 20%, 40%-50%, and 70%-80%, respectively, higher at urban than rural sites, indicating the regional scale impacts of SO42- and NH4+ and effects of local sources on OC and EC. Monthly variations generally showed summertime peaks for SO42- and wintertime peaks for NO3-, but those of NH4+, OC, and EC exhibited different seasonality at different locations.
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Affiliation(s)
- Huanbo Wang
- School of Environment and Resource, Southwest University of Science and Technology, Mianyang 621010, China
| | - Leiming Zhang
- Air Quality Research Division, Science and Technology Branch, Environment and Climate Change Canada, Toronto, Canada.
| | - Irene Cheng
- Air Quality Research Division, Science and Technology Branch, Environment and Climate Change Canada, Toronto, Canada
| | - Xiaohong Yao
- Lab of Marine Environmental Science and Ecology, Ministry of Education, Ocean University of China, Qingdao 266100, China
| | - Ewa Dabek-Zlotorzynska
- Air Quality Research Division, Science and Technology Branch, Environment and Climate Change Canada, Ottawa, Canada
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15
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June N, Wang X, Chen LWA, Chow JC, Watson JG, Wang X, Henderson BH, Zheng Y, Mao J. Spatial and temporal variability of brown carbon in United States: implications for direct radiative effects. GEOPHYSICAL RESEARCH LETTERS 2020; 47:10.1029/2020gl090332. [PMID: 34381286 PMCID: PMC8353956 DOI: 10.1029/2020gl090332] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 10/28/2020] [Indexed: 06/12/2023]
Abstract
A newly developed dataset from the Interagency Monitoring of PROtected Visual Environments (IMPROVE) observation network, combined with a 3-D chemical transport model, is used to evaluate the spatial and temporal variability of brown carbon (BrC) in the United States. The model with BrC emitted from biomass burning and biofuel emissions agrees with the seasonal and spatial variability of BrC planetary boundary layer (PBL) absorption aerosol optical depth (AAOD) observations within a factor of 2. The model without whitening, the tendency for absorption to decrease with aerosol aging, overestimates the observed BrC PBL AAOD, and does not reflect the measured BrC PBL AAOD spatial variability. The model shows higher absorption direct radiative effects (DRE) from BrC at northern high latitudes than at mid-latitudes in spring and summer, due to boreal fire emissions, long whitening lifetimes and high surface albedos. These findings highlight the need to study BrC over the Arctic region.
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Affiliation(s)
- Nicole June
- Department of Chemistry and Biochemistry and Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK, USA
| | - Xuan Wang
- School of Energy and Environment, City University of Hong Kong, Hong Kong SAR, China
| | - L.-W. Antony Chen
- Department of Environmental and Operational Health, University of Nevada, Las Vegas, NV, USA
| | - Judith C. Chow
- Division of Atmospheric Sciences, Desert Research Institute, Reno, NV, USA
| | - John G. Watson
- Division of Atmospheric Sciences, Desert Research Institute, Reno, NV, USA
| | - Xiaoliang Wang
- Division of Atmospheric Sciences, Desert Research Institute, Reno, NV, USA
| | - Barron H. Henderson
- Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA
| | - Yiqi Zheng
- Department of Chemistry and Biochemistry and Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK, USA
| | - Jingqiu Mao
- Department of Chemistry and Biochemistry and Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK, USA
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Heald CL, Gouw JD, Goldstein AH, Guenther AB, Hayes PL, Hu W, Isaacman-VanWertz G, Jimenez JL, Keutsch FN, Koss AR, Misztal PK, Rappenglück B, Roberts JM, Stevens PS, Washenfelder RA, Warneke C, Young CJ. Contrasting Reactive Organic Carbon Observations in the Southeast United States (SOAS) and Southern California (CalNex). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:14923-14935. [PMID: 33205951 DOI: 10.1021/acs.est.0c05027] [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: 06/11/2023]
Abstract
Despite the central role of reactive organic carbon (ROC) in the formation of secondary species that impact global air quality and climate, our assessment of ROC abundance and impacts is challenged by the diversity of species that contribute to it. We revisit measurements of ROC species made during two field campaigns in the United States: the 2013 SOAS campaign in forested Centreville, AL, and the 2010 CalNex campaign in urban Pasadena, CA. We find that average measured ROC concentrations are about twice as high in Pasadena (73.8 μgCsm-3) than in Centreville (36.5 μgCsm-3). However, the OH reactivity (OHR) measured at these sites is similar (20.1 and 19.3 s-1). The shortfall in OHR when summing up measured contributions is 31%, at Pasadena and 14% at Centreville, suggesting that there may be a larger reservoir of unmeasured ROC at the former site. Estimated O3 production and SOA potential (defined as concentration × yield) are both higher during CalNex than SOAS. This analysis suggests that the ROC in urban California is less reactive, but due to higher concentrations of oxides of nitrogen and hydroxyl radicals, is more efficient in terms of O3 and SOA production, than in the forested southeastern U.S.
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Affiliation(s)
- Colette L Heald
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Joost de Gouw
- Department of Chemistry, University of Colorado, Boulder, Colorado 80309, United States
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309, United States
| | - Allen H Goldstein
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, California 94720, United States
- Department of Civil and Environmental Engineering, University of California, Berkeley, California 94720, United States
| | - Alex B Guenther
- Department of Earth System Science, University of California, Irvine,California 92697, United States
| | - Patrick L Hayes
- Department of Chemistry, University of Colorado, Boulder, Colorado 80309, United States
| | - Weiwei Hu
- Department of Chemistry, University of Colorado, Boulder, Colorado 80309, United States
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309, United States
| | - Gabriel Isaacman-VanWertz
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, California 94720, United States
| | - Jose L Jimenez
- Department of Chemistry, University of Colorado, Boulder, Colorado 80309, United States
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309, United States
| | - Frank N Keutsch
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Abigail R Koss
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309, United States
- Chemical Sciences Laboratory, National Oceanic and Atmospheric Administration, Boulder, Colorado 80305, United States
| | - Pawel K Misztal
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, California 94720, United States
| | - Bernhard Rappenglück
- Department of Earth and Atmospheric Sciences, University of Houston, Houston, Texas 77204, United States
| | - James M Roberts
- Chemical Sciences Laboratory, National Oceanic and Atmospheric Administration, Boulder, Colorado 80305, United States
| | - Philip S Stevens
- O'Neill School of Public and Environmental Affairs, Indiana University, Bloomington, Indiana 47405, United States
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Rebecca A Washenfelder
- Chemical Sciences Laboratory, National Oceanic and Atmospheric Administration, Boulder, Colorado 80305, United States
| | - Carsten Warneke
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309, United States
- Chemical Sciences Laboratory, National Oceanic and Atmospheric Administration, Boulder, Colorado 80305, United States
| | - Cora J Young
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309, United States
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O'Dell K, Hornbrook RS, Permar W, Levin EJT, Garofalo LA, Apel EC, Blake NJ, Jarnot A, Pothier MA, Farmer DK, Hu L, Campos T, Ford B, Pierce JR, Fischer EV. Hazardous Air Pollutants in Fresh and Aged Western US Wildfire Smoke and Implications for Long-Term Exposure. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:11838-11847. [PMID: 32857515 DOI: 10.1021/acs.est.0c04497] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Wildfires have a significant adverse impact on air quality in the United States (US). To understand the potential health impacts of wildfire smoke, many epidemiology studies rely on concentrations of fine particulate matter (PM) as a smoke tracer. However, there are many gas-phase hazardous air pollutants (HAPs) identified by the Environmental Protection Agency (EPA) that are also present in wildfire smoke plumes. Using observations from the Western Wildfire Experiment for Cloud Chemistry, Aerosol Absorption, and Nitrogen (WE-CAN), a 2018 aircraft-based field campaign that measured HAPs and PM in western US wildfire smoke plumes, we identify the relationships between HAPs and associated health risks, PM, and smoke age. We find the ratios between acute, chronic noncancer, and chronic cancer HAPs health risk and PM in smoke decrease as a function of smoke age by up to 72% from fresh (<1 day of aging) to old (>3 days of aging) smoke. We show that acrolein, formaldehyde, benzene, and hydrogen cyanide are the dominant contributors to gas-phase HAPs risk in smoke plumes. Finally, we use ratios of HAPs to PM along with annual average smoke-specific PM to estimate current and potential future smoke HAPs risks.
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Affiliation(s)
- Katelyn O'Dell
- Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado 80521, United States
| | - Rebecca S Hornbrook
- Atmospheric Chemistry Division, National Center for Atmospheric Research, Boulder, Colorado 80301, United States
| | - Wade Permar
- Department of Chemistry and Biochemistry, University of Montana, Missoula, Montana 59812, United States
| | - Ezra J T Levin
- Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado 80521, United States
| | - Lauren A Garofalo
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Eric C Apel
- Atmospheric Chemistry Division, National Center for Atmospheric Research, Boulder, Colorado 80301, United States
| | - Nicola J Blake
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Alex Jarnot
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Matson A Pothier
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Delphine K Farmer
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Lu Hu
- Department of Chemistry and Biochemistry, University of Montana, Missoula, Montana 59812, United States
| | - Teresa Campos
- Atmospheric Chemistry Division, National Center for Atmospheric Research, Boulder, Colorado 80301, United States
| | - Bonne Ford
- Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado 80521, United States
| | - Jeffrey R Pierce
- Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado 80521, United States
| | - Emily V Fischer
- Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado 80521, United States
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Carlton AG, Christiansen AE, Flesch MM, Hennigan CJ, Sareen N. Mulitphase Atmospheric Chemistry in Liquid Water: Impacts and Controllability of Organic Aerosol. Acc Chem Res 2020; 53:1715-1723. [PMID: 32803954 DOI: 10.1021/acs.accounts.0c00301] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Liquid water is a dominant and critical tropospheric constituent. Over polluted land masses low level cumulus clouds interact with boundary layer aerosol. The planetary boundary layer (PBL) is the lowest atmospheric layer and is directly influenced by Earth's surface. Water-aerosol interactions are critical to processes that govern the fate and transport of trace species in the Earth system and their impacts on air quality, radiative forcing, and regional hydrological cycling. In the PBL, air parcels rise adiabatically from the surface, and anthropogenically influenced hygroscopic aerosols take up water and serve as cloud condensation nuclei (CCN) to form clouds. Water-soluble gases partition to liquid water in wet aerosols and cloud droplets and undergo aqueous-phase photochemistry. Most cloud droplets evaporate, and low volatility material formed during aqueous phase chemistry remains in the condensed phase and adds to aerosol mass. The resulting cloud-processed aerosol has different physicochemical properties compared to the original CCN. Organic species that undergo multiphase chemistry in atmospheric liquid water transform gases to highly concentrated, nonideal ionic aqueous solutions and form secondary organic aerosol (SOA). In recent years, SOA formation modulated by atmospheric waters has received considerable interest.Key uncertainties are related to the chemical nature of hygroscopic aerosols that become CCN and their interaction with organic species. Gas-to-droplet or gas-to-aqueous aerosol partitioning of organic compounds is affected by the intrinsic chemical properties of the organic species in addition to the pre-existing condensed phase. Environmentally relevant conditions for atmospheric aerosol are nonideal. Salt identity and concentration, in addition to aerosol phase state, can dramatically affect organic gas miscibility for many compounds, in particular when ionic strength and salt molality are outside the bounds of limiting laws. For example, Henry's law and Debye-Hückel theory are valid only for dilute aqueous systems uncharacteristic of real atmospheric conditions. Chemical theory is incomplete, and at ambient conditions, this chemistry plays a determining role in total aerosol mass and particle size, controlling factors for air quality and climate-relevant aerosol properties.Accurate predictive skill to understand the impacts of societal choices and policies on air quality and climate requires that models contain correct chemical mechanisms and appropriate feedbacks. Globally, SOA is a dominant contributor to the atmospheric organic aerosol burden, and most mass can be traced back to precursor gas-phase volatile organic compounds (VOCs) emitted from the biosphere. However, organic aerosol concentrations in the Amazon Rainforest, the largest emitter of biogenic VOCs, are generally lower than in U.S. national parks. The Interagency Monitoring of Protected Visual Environments (IMPROVE) air quality network, with sites located predominantly in national parks, provides the longest continuous record of organic aerosol measurements in the U.S. Analysis of IMPROVE data provides a useful chemical climatology of changing air resources in response to environmental rules and shifting economic trends. IMPROVE data provides an excellent test bed for case studies to assess model skill to accurately predict changes in organic aerosol concentrations in the context of a changing climate.
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Affiliation(s)
- Annmarie G. Carlton
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Amy E. Christiansen
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Madison M. Flesch
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Christopher J. Hennigan
- Department of Chemical, Biochemical and Environmental Engineering, University of Maryland, Baltimore County, Baltimore, Maryland 21250, United States
| | - Neha Sareen
- U.S. EPA-Region 2, 290 Broadway, New York, NY 10007, United States
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Christiansen AE, Carlton AG, Porter WC. Changing Nature of Organic Carbon over the United States. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:10524-10532. [PMID: 32464056 DOI: 10.1021/acs.est.0c02225] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Total organic carbon (TOC) mass concentrations are decreasing across the contiguous United States (CONUS). We investigate decadal trends in organic carbon (OC) thermal fractions [OC1 (volatilizes at 140 °C), OC2 (280 °C), OC3 (480 °C), OC4 (580 °C)] and pyrolyzed carbon (PC), reported at 121 locations in the Interagency Monitoring of Protected Visual Environments (IMPROVE) network from 2005 to 2015 for 23 regions across the CONUS. Reductions in PC and OC2 drive decreases in TOC (TOC = OC1 + OC2 + OC3 + OC4 + PC) mass concentrations. OC2 decreases by 40% from 2005 to 2015, and PC decreases by 34%. The largest absolute mass decreases occur in the eastern United States, and relative changes normalized to local concentrations are more uniform across the CONUS. OC is converted to organic mass (OM) using region- and season-specific OM:OC ratios. Simulations with GEOS-Chem reproduce OM trends and suggest that decreases across the CONUS are due to aerosol liquid water (ALW) chemistry. Individual model species, notably aerosol derived from isoprene oxidation products and formed in ALW, correlate significantly (p < 0.05) with OM2, even in arid regions. These findings contribute to literature that suggests air quality rules aimed at SO2 and NOx emissions induce the cobenefit of reducing organic particle mass through ALW chemistry, and these benefits extend beyond the eastern United States.
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Affiliation(s)
- Amy E Christiansen
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - Annmarie G Carlton
- Department of Chemistry, University of California, Irvine, California 92697, United States
| | - William C Porter
- Department of Environmental Sciences, University of California, Riverside, California 92521, United States
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20
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Jiang H, Ahmed CMS, Zhao Z, Chen JY, Zhang H, Canchola A, Lin YH. Role of functional groups in reaction kinetics of dithiothreitol with secondary organic aerosols. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 263:114402. [PMID: 32247903 DOI: 10.1016/j.envpol.2020.114402] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 03/13/2020] [Accepted: 03/16/2020] [Indexed: 05/21/2023]
Abstract
The toxicity of organic aerosols has been largely ascribed to the generation of reactive oxygen species, which could subsequently induce oxidative stress in biological systems. The reaction of DTT with redox-active species in PM has been generally assumed to be pseudo-first order, with the oxidative potential of PM being represented by the DTT consumption per minute of reaction time per μg of PM. Although catalytic reactive species such as transition metals and quinones are long believed to be the main contributors of DTT responses, the role of non-catalytic DTT reactive species such as organic hydroperoxides (ROOH) and electron-deficient alkenes (e.g., conjugated carbonyls) in DTT consumption has been recently highlighted. Thus, understanding the reaction kinetics and mechanisms of DTT consumption by various PM components is required to interpret the oxidative potential measured by DTT assays more accurately. In this study, we measured the DTT consumptions over time and characterized the reaction products using model compounds and secondary organic aerosols (SOA) with varying initial concentrations. We observed that the DTT consumption rates linearly increased with both initial DTT and sample concentrations. The overall reaction order of DTT with non-catalytic reactive species and SOA in this study is second order. The reactions of DTT with different functional groups have significantly different rate constants. The reaction rate constant of isoprene SOA with DTT is mainly determined by the concentration of ROOH. For toluene SOA, both ROOH and electron-deficient alkenes may dominate its DTT reaction rates. These results provide some insights into the interpretation of DTT-based aerosol oxidative potential and highlight the need to study the toxicity mechanism of ROOH and electron-deficient alkenes in PM for future work.
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Affiliation(s)
- Huanhuan Jiang
- Department of Environmental Sciences, University of California, Riverside, CA, 92521, United States
| | - C M Sabbir Ahmed
- Environmental Toxicology Graduate Program, University of California, Riverside, CA, 92521, United States
| | - Zixu Zhao
- Department of Chemistry, University of California, Riverside, CA, 92521, United States
| | - Jin Y Chen
- Environmental Toxicology Graduate Program, University of California, Riverside, CA, 92521, United States
| | - Haofei Zhang
- Environmental Toxicology Graduate Program, University of California, Riverside, CA, 92521, United States; Department of Chemistry, University of California, Riverside, CA, 92521, United States
| | - Alexa Canchola
- Environmental Toxicology Graduate Program, University of California, Riverside, CA, 92521, United States
| | - Ying-Hsuan Lin
- Department of Environmental Sciences, University of California, Riverside, CA, 92521, United States; Environmental Toxicology Graduate Program, University of California, Riverside, CA, 92521, United States.
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21
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Wong JPS, Yang Y, Fang T, Mulholland JA, Russell AG, Ebelt S, Nenes A, Weber RJ. Fine Particle Iron in Soils and Road Dust Is Modulated by Coal-Fired Power Plant Sulfur. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:7088-7096. [PMID: 32391689 DOI: 10.1021/acs.est.0c00483] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Transition metal ions, such as water-soluble iron (WS-Fe), are toxic components of fine particles (PM2.5). In Atlanta, from 1998 to 2013, a previous study found that WS-Fe was the PM2.5 species most associated with adverse cardiovascular outcomes. We examined this data set to investigate the sources of WS-Fe and the effects of air quality regulations on ambient levels of WS-Fe. We find that insoluble forms of iron in mineral and road dust combined with sulfate from coal-fired electrical generating units were converted into soluble forms by sulfate-driven acid dissolution. Sulfate produced both the highly acidic aerosol (summer pH 1.5-2) and liquid water required for the aqueous phase acid dissolution, but variability in WS-Fe was mainly driven by particle liquid water. These processes were more pronounced in summer when particles were most acidic, whereas in winter the relative importance of WS-Fe from combustion emissions increased. Although WS-Fe constituted a minute fraction of PM2.5 mass (0.15%), the WS-Fe-PM2.5 mass correlation was high (r = 0.67) and may be explained by these formation routes, which, in part, could account for observed associations between PM2.5 mass and adverse health seen in past studies. Similar processes are expected in many regions, implying that these unexpected benefits from coal-burning reduction may be widespread.
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Affiliation(s)
- Jenny P S Wong
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, 311 Ferst Drive, Atlanta, Georgia 30332, United States
- Department of Chemistry and Biochemistry, Mount Allison University, Sackville E4L 1G8, Canada
| | - Yuhan Yang
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, 311 Ferst Drive, Atlanta, Georgia 30332, United States
| | - Ting Fang
- Department of Chemistry, University of California Irvine, Irvine, California 92697, United States
| | - James A Mulholland
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30331, United States
| | - Armistead G Russell
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30331, United States
| | - Stefanie Ebelt
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia 30322, United States
| | - Athanasios Nenes
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, 311 Ferst Drive, Atlanta, Georgia 30332, United States
- Institute of Chemical Engineering Science, Foundation for Research and Technology, Patras GR-26504, Greece
- Laboratory of Atmospheric Processes and their Impacts, School of Architecture, Civil & Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne 1015, Switzerland
| | - Rodney J Weber
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, 311 Ferst Drive, Atlanta, Georgia 30332, United States
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22
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Meng J, Martin RV, Li C, van Donkelaar A, Tzompa-Sosa ZA, Yue X, Xu JW, Weagle CL, Burnett RT. Source Contributions to Ambient Fine Particulate Matter for Canada. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:10269-10278. [PMID: 31386807 DOI: 10.1021/acs.est.9b02461] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Understanding the sectoral contribution of emissions to fine particulate matter (PM2.5) offers information for air quality management, and for investigation of association with health outcomes. This study evaluates the contribution of different emission sectors to PM2.5 in 2013 for Canada using the GEOS-Chem chemical transport model, downscaled with satellite-based PM2.5. Despite the low population-weighted PM2.5 concentrations of 5.5 μg m-3 across Canada, we find that over 70% of population-weighted PM2.5 originates from Canadian sources followed by 30% from the contiguous United States. The three leading sectoral contributors to population-weighted PM2.5 over Canada are wildfires with 1.0 μg m-3 (17%), transportation with 0.96 μg m-3 (16%), and residential combustion with 0.91 μg m-3 (15%). The relative contribution to population-weighted PM2.5 of different sectors varies regionally with residential combustion as the leading contributor in Central Canada (19%), while wildfires dominate over Northern Canada (59%), Atlantic Canada (34%), and Western Canada (18%). The contribution from U.S. sources is larger over Central Canada (33%) than over Western Canada (17%), Atlantic Canada (17%), and Northern Canada (<2%). Sectoral trend analysis showed that the contribution from anthropogenic sources to population-weighted PM2.5 decreased from 7.1 μg m-3 to 3.4 μg m-3 over the past two decades.
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Affiliation(s)
- Jun Meng
- Department of Physics and Atmospheric Science , Dalhousie University , Halifax , Nova Scotia B3H 4R2 , Canada
| | - Randall V Martin
- Department of Physics and Atmospheric Science , Dalhousie University , Halifax , Nova Scotia B3H 4R2 , Canada
- Smithsonian Astrophysical Observatory , Harvard-Smithsonian Center for Astrophysics , Cambridge , Massachusetts 02138 , United States
- Department of Energy, Environmental & Chemical Engineering , Washington University in St. Louis , St. Louis , Missouri 63130 , United States
| | - Chi Li
- Department of Physics and Atmospheric Science , Dalhousie University , Halifax , Nova Scotia B3H 4R2 , Canada
| | - Aaron van Donkelaar
- Department of Physics and Atmospheric Science , Dalhousie University , Halifax , Nova Scotia B3H 4R2 , Canada
| | - Zitely A Tzompa-Sosa
- Department of Atmospheric Science , Colorado State University , Fort Collins , Colorado 80523 , United States
| | - Xu Yue
- School of Environmental Science and Engineering , Nanjing University of Information Science & Technology , Nanjing 210044 , China
| | - Jun-Wei Xu
- Department of Physics and Atmospheric Science , Dalhousie University , Halifax , Nova Scotia B3H 4R2 , Canada
| | - Crystal L Weagle
- Department of Physics and Atmospheric Science , Dalhousie University , Halifax , Nova Scotia B3H 4R2 , Canada
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Liu Y, Zhao N, Vanos JK, Cao G. Revisiting the estimations of PM 2.5-attributable mortality with advancements in PM 2.5 mapping and mortality statistics. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 666:499-507. [PMID: 30802665 DOI: 10.1016/j.scitotenv.2019.02.269] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 02/17/2019] [Accepted: 02/17/2019] [Indexed: 06/09/2023]
Abstract
With the advancements of geospatial technologies, geospatial datasets of fine particulate matter (PM2.5) and mortality statistics are increasingly used to examine the health effects of PM2.5. Choices of these datasets with difference geographic characteristics (e.g., accuracy, scales, and variations) in disease burden studies can significantly impact the results. The objective of this study is to revisit the estimations of PM2.5-attributable mortality by taking advantage of recent advancements in high resolution mapping of PM2.5concentrations and fine scale of mortality statistics and to explore the impacts of new data sources, geographic scales, and spatial variations of input datasets on mortality estimations. We estimate the PM2.5-mortality for the years of 2000, 2005, 2010 and 2015 using three PM2.5 concentration datasets [Chemical Transport Model (CTM), random forests-based regression kriging (RFRK), and geographically weighted regression (GWR)] at two resolutions (i.e., 10 km and 1 km) and mortality rates at two geographic scales (i.e., regional-level and county-level). The results show that the estimated PM2.5-mortality from the 10 km CTM-derived PM2.5 dataset tend to be smaller than the estimations from the 1 km RFRK- and GWR-derived PM2.5 datasets. The estimated PM2.5-mortalities from regional-level mortality rates are similar to the estimations from those at county level, while large deviations exist when zoomed into small geographic regions (e.g., county). In a scenario analysis to explore the possible benefits of PM2.5 concentrations reduction, the uses of the two newly developed 1 km resolution PM2.5 datasets (RFRK and GWR) lead to discrepant results. Furthermore, we found that the change in PM2.5 concentration is the primary factor that leads to the PM2.5-attributable mortality decrease from 2000 to 2015. The above results highlight the impact of the adoption of input datasets from new sources with varied geographic characteristics on the PM2.5-attributable mortality estimations and demonstrate the necessity to account for these impact in future disease burden studies. CAPSULE: We revisited the estimations of PM2.5-attributable mortality with advancements in PM2.5 mapping and mortality statistics, and demonstrated the impact of geographic characteristics of geospatial datasets on mortality estimations.
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Affiliation(s)
- Ying Liu
- Department of Geosciences, Texas Tech University, Lubbock, TX 79409, USA; Center for Geospatial Technology, Texas Tech University, Lubbock, TX 79409, USA
| | - Naizhuo Zhao
- Center for Geospatial Technology, Texas Tech University, Lubbock, TX 79409, USA
| | - Jennifer K Vanos
- School of Sustainability, Arizona State University, Tempe, AZ 85287, USA
| | - Guofeng Cao
- Department of Geosciences, Texas Tech University, Lubbock, TX 79409, USA; Center for Geospatial Technology, Texas Tech University, Lubbock, TX 79409, USA.
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24
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Meng J, Li C, Martin RV, van Donkelaar A, Hystad P, Brauer M. Estimated Long-Term (1981-2016) Concentrations of Ambient Fine Particulate Matter across North America from Chemical Transport Modeling, Satellite Remote Sensing, and Ground-Based Measurements. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:5071-5079. [PMID: 30995030 DOI: 10.1021/acs.est.8b06875] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Accurate data concerning historical fine particulate matter (PM2.5) concentrations are needed to assess long-term changes in exposure and associated health risks. We estimated historical PM2.5 concentrations over North America from 1981 to 2016 for the first time by combining chemical transport modeling, satellite remote sensing, and ground-based measurements. We constrained and evaluated our estimates with direct ground-based PM2.5 measurements when available and otherwise with historical estimates of PM2.5 from PM10 measurements or total suspended particle (TSP) measurements. The estimated PM2.5 concentrations were generally consistent with direct ground-based PM2.5 measurements over their duration from 1988 onward ( R2 = 0.6 to 0.85) and to a lesser extent with PM2.5 inferred from PM10 measurements from 1985 to 1998 ( R2 = 0.5 to 0.6). The collocated comparison of the trends of population-weighted annual average PM2.5 from our estimates and ground-based measurements was highly consistent (RMSD = 0.66 μg m-3). The population-weighted annual average PM2.5 over North America decreased from 22 ± 6.4 μg m-3 in 1981, to 12 ± 3.2 μg m-3 in 1998, and to 7.9 ± 2.1 μg m-3 in 2016, with an overall trend of -0.33 μg m-3 yr-1 (95% CI: -0.35, -0.31).
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Affiliation(s)
- Jun Meng
- Department of Physics and Atmospheric Science , Dalhousie University , Halifax , Nova Scotia B3H 4R2 , Canada
| | - Chi Li
- Department of Physics and Atmospheric Science , Dalhousie University , Halifax , Nova Scotia B3H 4R2 , Canada
| | - Randall V Martin
- Department of Physics and Atmospheric Science , Dalhousie University , Halifax , Nova Scotia B3H 4R2 , Canada
- Smithsonian Astrophysical Observatory , Harvard-Smithsonian Center for Astrophysics , Cambridge , Massachusetts 02138 , United States
| | - Aaron van Donkelaar
- Department of Physics and Atmospheric Science , Dalhousie University , Halifax , Nova Scotia B3H 4R2 , Canada
| | - Perry Hystad
- College of Public Health and Human Sciences , Oregon State University , Corvallis , Oregon 97331 , United States
| | - Michael Brauer
- School of Population and Public Health , The University of British Columbia , 2206 East Mall , Vancouver , British Columbia V6T 1Z3 , Canada
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25
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Pye HOT, D'Ambro EL, Lee BH, Schobesberger S, Takeuchi M, Zhao Y, Lopez-Hilfiker F, Liu J, Shilling JE, Xing J, Mathur R, Middlebrook AM, Liao J, Welti A, Graus M, Warneke C, de Gouw JA, Holloway JS, Ryerson TB, Pollack IB, Thornton JA. Anthropogenic enhancements to production of highly oxygenated molecules from autoxidation. Proc Natl Acad Sci U S A 2019; 116:6641-6646. [PMID: 30886090 PMCID: PMC6452672 DOI: 10.1073/pnas.1810774116] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Atmospheric oxidation of natural and anthropogenic volatile organic compounds (VOCs) leads to secondary organic aerosol (SOA), which constitutes a major and often dominant component of atmospheric fine particulate matter (PM2.5). Recent work demonstrates that rapid autoxidation of organic peroxy radicals (RO2) formed during VOC oxidation results in highly oxygenated organic molecules (HOM) that efficiently form SOA. As NOx emissions decrease, the chemical regime of the atmosphere changes to one in which RO2 autoxidation becomes increasingly important, potentially increasing PM2.5, while oxidant availability driving RO2 formation rates simultaneously declines, possibly slowing regional PM2.5 formation. Using a suite of in situ aircraft observations and laboratory studies of HOM, together with a detailed molecular mechanism, we show that although autoxidation in an archetypal biogenic VOC system becomes more competitive as NOx decreases, absolute HOM production rates decrease due to oxidant reductions, leading to an overall positive coupling between anthropogenic NOx and localized biogenic SOA from autoxidation. This effect is observed in the Atlanta, Georgia, urban plume where HOM is enhanced in the presence of elevated NO, and predictions for Guangzhou, China, where increasing HOM-RO2 production coincides with increases in NO from 1990 to 2010. These results suggest added benefits to PM2.5 abatement strategies come with NOx emission reductions and have implications for aerosol-climate interactions due to changes in global SOA resulting from NOx interactions since the preindustrial era.
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Affiliation(s)
- Havala O T Pye
- National Exposure Research Laboratory, Environmental Protection Agency, Research Triangle Park, NC 27711;
- Department of Atmospheric Science, University of Washington, Seattle, WA 98195
| | - Emma L D'Ambro
- Department of Atmospheric Science, University of Washington, Seattle, WA 98195
- Department of Chemistry, University of Washington, Seattle, WA 98195
| | - Ben H Lee
- Department of Atmospheric Science, University of Washington, Seattle, WA 98195
| | - Siegfried Schobesberger
- Department of Atmospheric Science, University of Washington, Seattle, WA 98195
- Department of Applied Physics, University of Eastern Finland, 70211 Kuopio, Finland
| | - Masayuki Takeuchi
- National Exposure Research Laboratory, Environmental Protection Agency, Research Triangle Park, NC 27711
| | - Yue Zhao
- Department of Atmospheric Science, University of Washington, Seattle, WA 98195
| | | | - Jiumeng Liu
- Atmospheric Sciences and Global Change Division, Pacific Northwest National Laboratory, Richland, WA 99352
| | - John E Shilling
- Atmospheric Sciences and Global Change Division, Pacific Northwest National Laboratory, Richland, WA 99352
| | - Jia Xing
- National Exposure Research Laboratory, Environmental Protection Agency, Research Triangle Park, NC 27711
| | - Rohit Mathur
- National Exposure Research Laboratory, Environmental Protection Agency, Research Triangle Park, NC 27711
| | - Ann M Middlebrook
- Chemical Sciences Division, National Oceanic and Atmospheric Administration Earth System Research Laboratory, Boulder, CO 80305
| | - Jin Liao
- Chemical Sciences Division, National Oceanic and Atmospheric Administration Earth System Research Laboratory, Boulder, CO 80305
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309
| | - André Welti
- Chemical Sciences Division, National Oceanic and Atmospheric Administration Earth System Research Laboratory, Boulder, CO 80305
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309
| | - Martin Graus
- Chemical Sciences Division, National Oceanic and Atmospheric Administration Earth System Research Laboratory, Boulder, CO 80305
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309
| | - Carsten Warneke
- Chemical Sciences Division, National Oceanic and Atmospheric Administration Earth System Research Laboratory, Boulder, CO 80305
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309
| | - Joost A de Gouw
- Chemical Sciences Division, National Oceanic and Atmospheric Administration Earth System Research Laboratory, Boulder, CO 80305
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309
| | - John S Holloway
- Chemical Sciences Division, National Oceanic and Atmospheric Administration Earth System Research Laboratory, Boulder, CO 80305
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309
| | - Thomas B Ryerson
- Chemical Sciences Division, National Oceanic and Atmospheric Administration Earth System Research Laboratory, Boulder, CO 80305
| | - Ilana B Pollack
- Chemical Sciences Division, National Oceanic and Atmospheric Administration Earth System Research Laboratory, Boulder, CO 80305
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309
| | - Joel A Thornton
- Department of Atmospheric Science, University of Washington, Seattle, WA 98195;
- Department of Chemistry, University of Washington, Seattle, WA 98195
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26
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Reid CE, Maestas MM. Wildfire smoke exposure under climate change: impact on respiratory health of affected communities. Curr Opin Pulm Med 2019; 25:179-187. [PMID: 30461534 PMCID: PMC6743728 DOI: 10.1097/mcp.0000000000000552] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
PURPOSE OF REVIEW In this review, we describe the current status of the literature regarding respiratory health related to wildfire smoke exposure, anticipated future impacts under a changing climate, and strategies to reduce respiratory health impacts of wildfire smoke. RECENT FINDINGS Recent findings confirm associations between wildfire smoke exposure and respiratory health outcomes, with the clearest evidence for exacerbations of asthma. Although previous evidence showed a clear association between wildfire smoke and chronic obstructive pulmonary disease, findings from recent studies are more mixed. Current evidence in support of an association between respiratory infections and wildfire smoke exposure is also mixed. Only one study has investigated long-term respiratory health impacts of wildfire smoke, and few studies have estimated future health impacts of wildfires under likely climate change scenarios. SUMMARY Wildfire activity has been increasing over the past several decades and is likely to continue to do so as climate change progresses, which, combined with a growing population, means that population exposure to and respiratory health impacts of wildfire smoke is likely to grow in the future. More research is needed to understand which population subgroups are most vulnerable to wildfire smoke exposure and the long-term respiratory health impacts of these high pollution events.
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Affiliation(s)
| | - Melissa May Maestas
- Cooperative Institute for Research in Environmental Sciences, Earth Lab, University of Colorado Boulder, Boulder, Colorado, USA
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27
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O'Dell K, Ford B, Fischer EV, Pierce JR. Contribution of Wildland-Fire Smoke to US PM 2.5 and Its Influence on Recent Trends. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:1797-1804. [PMID: 30681842 DOI: 10.1021/acs.est.8b05430] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Seasonal-mean concentrations of particulate matter with diameters smaller than 2.5 μm (PM2.5) have been decreasing across the United States (US) for several decades, with large reductions in spring and summer in the eastern US. In contrast, summertime-mean PM2.5 in the western US has not significantly decreased. Wildfires, a large source of summertime PM2.5 in the western US, have been increasing in frequency and burned area in recent decades. Increases in extreme PM2.5 events attributable to wildland fires have been observed in wildfire-prone regions, but it is unclear how these increases impact trends in seasonal-mean PM2.5. Using two distinct methods, (1) interpolated surface observations combined with satellite-based smoke plume estimates and (2) the GEOS-Chem chemical transport model (CTM), we identify recent trends (2006-2016) in summer smoke, nonsmoke, and total PM2.5 across the US. We observe significant decreases in nonsmoke influenced PM2.5 in the western US and find increases in summer-mean smoke PM2.5 in fire-prone regions, although these are not statistically significant due to large interannual variability in the abundance of smoke. These results indicate that without the influence of wildland fires, we would expect to have observed improvements in summer fine particle pollution in the western US but likely weaker improvements than those observed in the eastern US.
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Affiliation(s)
- Katelyn O'Dell
- Department of Atmospheric Science , Colorado State University , 200 West Lake Street, 1371 Campus Delivery , Fort Collins , Colorado 80523 , United States
| | - Bonne Ford
- Department of Atmospheric Science , Colorado State University , 200 West Lake Street, 1371 Campus Delivery , Fort Collins , Colorado 80523 , United States
| | - Emily V Fischer
- Department of Atmospheric Science , Colorado State University , 200 West Lake Street, 1371 Campus Delivery , Fort Collins , Colorado 80523 , United States
| | - Jeffrey R Pierce
- Department of Atmospheric Science , Colorado State University , 200 West Lake Street, 1371 Campus Delivery , Fort Collins , Colorado 80523 , United States
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28
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Carlton AG, Pye HOT, Baker KR, Hennigan CJ. Additional Benefits of Federal Air-Quality Rules: Model Estimates of Controllable Biogenic Secondary Organic Aerosol. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:9254-9265. [PMID: 30005158 PMCID: PMC6748392 DOI: 10.1021/acs.est.8b01869] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Atmospheric models that accurately describe the fate and transport of trace species for the right reasons aid in the development of effective air-quality management strategies that safeguard human health. Controllable emissions facilitate the formation of biogenic secondary organic aerosol (BSOA) to enhance the atmospheric fine particulate matter (PM2.5) burden. Previous modeling with the EPA's Community Multiscale Air Quality (CMAQ) model predicted that anthropogenic primary organic aerosol (POA) emissions had the greatest impact on BSOA. That experiment included formation processes involving semivolatile partitioning but not aerosol liquid water (ALW), a ubiquitous PM constituent. We conduct 17 summertime CMAQ simulations with updated chemistry and evaluate changes in BSOA due to the removal of individual pollutants and source sectors for the contiguous U.S. CMAQ predicts SO2 from electricity generating units, and mobile source NOX emissions have the largest impacts on BSOA. The removal of anthropogenic NOX, SO2, and POA emissions during the simulation reduces the nationally averaged BSOA by 23, 14, and 8% and PM2.5 by 9.2, 14, and 5.3%, respectively. ALW mass concentrations decrease by 10 and 35% in response to the removal of NOX and SO2 emissions. This work contributes chemical insight into ancillary benefits of Federal NOX and SO2 rules that concurrently reduce organic PM2.5 mass.
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Affiliation(s)
- Annmarie G Carlton
- Department of Chemistry , University of California , Irvine , California 92697 , United States
| | - Havala O T Pye
- Office of Research and Development , U.S. EPA , Research Triangle Park , North Carolina 27709 , United States
| | - Kirk R Baker
- Office of Air Quality Planning and Standards , U.S. EPA , Research Triangle Park , North Carolina 27709 , United States
| | - Christopher J Hennigan
- Department of Chemical, Biochemical and Environmental Engineering , University of Maryland , Baltimore County, Maryland 21250 , United States
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Saha PK, Reece SM, Grieshop AP. Seasonally Varying Secondary Organic Aerosol Formation From In-Situ Oxidation of Near-Highway Air. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:7192-7202. [PMID: 29847110 DOI: 10.1021/acs.est.8b01134] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The extent to which motor vehicles contribute to ambient secondary organic aerosol (SOA) remains uncertain. Here, we present in situ measurements of SOA formation at a near-highway site with substantial tree-cover 10 m from Interstate 40 near Durham, North Carolina. In July 2015 (summer) and February 2016 (winter), we exposed ambient air to a range of oxidant (O3 and OH) concentrations in an oxidation flow reactor (OFR), resulting in hours to weeks of equivalent atmospheric aging. We observed substantial seasonal variation in SOA formation upon OFR aging; diurnally varying OA enhancements of ∼3-8 μg m-3 were observed in summer and significantly lower enhancements (∼0.5-1 μg m-3) in winter. Measurements in both seasons showed consistent changes in bulk OA properties (chemical composition; volatility) with OFR aging. Mild increases in traffic-related SOA precursors during summer partly explains the seasonal variation. However, biogenic emissions, with sharp temperature dependence, appear to dominate summer OFR-SOA. Our analysis indicates that SOA observed in the OFR is similar (within a factor of 2) to that predicted to form from traffic and biogenic precursors using literature yields, especially in winter. This study highlights the utility of the OFR for studying the prevalence of SOA precursors in complex real-world settings.
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Affiliation(s)
- Provat K Saha
- Department of Civil, Construction and Environmental Engineering , North Carolina State University , 431B Mann Hall , Raleigh , North Carolina 27695 , United States
| | - Stephen M Reece
- Department of Civil, Construction and Environmental Engineering , North Carolina State University , 431B Mann Hall , Raleigh , North Carolina 27695 , United States
| | - Andrew P Grieshop
- Department of Civil, Construction and Environmental Engineering , North Carolina State University , 431B Mann Hall , Raleigh , North Carolina 27695 , United States
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Li C, Martin RV, van Donkelaar A, Boys BL, Hammer MS, Xu JW, Marais EA, Reff A, Strum M, Ridley DA, Crippa M, Brauer M, Zhang Q. Trends in Chemical Composition of Global and Regional Population-Weighted Fine Particulate Matter Estimated for 25 Years. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:11185-11195. [PMID: 28891283 DOI: 10.1021/acs.est.7b02530] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
We interpret in situ and satellite observations with a chemical transport model (GEOS-Chem, downscaled to 0.1° × 0.1°) to understand global trends in population-weighted mean chemical composition of fine particulate matter (PM2.5). Trends in observed and simulated population-weighted mean PM2.5 composition over 1989-2013 are highly consistent for PM2.5 (-2.4 vs -2.4%/yr), secondary inorganic aerosols (-4.3 vs -4.1%/yr), organic aerosols (OA, -3.6 vs -3.0%/yr) and black carbon (-4.3 vs -3.9%/yr) over North America, as well as for sulfate (-4.7 vs -5.8%/yr) over Europe. Simulated trends over 1998-2013 also have overlapping 95% confidence intervals with satellite-derived trends in population-weighted mean PM2.5 for 20 of 21 global regions. Over 1989-2013, most (79%) of the simulated increase in global population-weighted mean PM2.5 of 0.28 μg m-3yr-1 is explained by significantly (p < 0.05) increasing OA (0.10 μg m-3yr-1), nitrate (0.05 μg m-3yr-1), sulfate (0.04 μg m-3yr-1), and ammonium (0.03 μg m-3yr-1). These four components predominantly drive trends in population-weighted mean PM2.5 over populous regions of South Asia (0.94 μg m-3yr-1), East Asia (0.66 μg m-3yr-1), Western Europe (-0.47 μg m-3yr-1), and North America (-0.32 μg m-3yr-1). Trends in area-weighted mean and population-weighted mean PM2.5 composition differ significantly.
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Affiliation(s)
- Chi Li
- Department of Physics and Atmospheric Science, Dalhousie University , Halifax, Nova Scotia B3H 4R2, Canada
| | - Randall V Martin
- Department of Physics and Atmospheric Science, Dalhousie University , Halifax, Nova Scotia B3H 4R2, Canada
- Harvard-Smithsonian Center for Astrophysics , Cambridge, Massachusetts 02138, United States
| | - Aaron van Donkelaar
- Department of Physics and Atmospheric Science, Dalhousie University , Halifax, Nova Scotia B3H 4R2, Canada
| | - Brian L Boys
- Department of Physics and Atmospheric Science, Dalhousie University , Halifax, Nova Scotia B3H 4R2, Canada
| | - Melanie S Hammer
- Department of Physics and Atmospheric Science, Dalhousie University , Halifax, Nova Scotia B3H 4R2, Canada
| | - Jun-Wei Xu
- Department of Physics and Atmospheric Science, Dalhousie University , Halifax, Nova Scotia B3H 4R2, Canada
| | - Eloise A Marais
- School of Geography, Earth and Environmental Sciences, University of Birmingham , Birmingham B15 2TT, United Kingdom
| | - Adam Reff
- U.S. Environmental Protection Agency , Research Triangle Park, North Carolina 27711, United States
| | - Madeleine Strum
- U.S. Environmental Protection Agency , Research Triangle Park, North Carolina 27711, United States
| | - David A Ridley
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139-4307, United States
| | - Monica Crippa
- European Commission, Joint Research Centre (JRC) , Directorate for Energy, Transport, and Climate, Air and Climate Unit, Via E. Fermi 2749, I-21027 Ispra, Varese, Italy
| | - Michael Brauer
- School of Population and Public Health, The University of British Columbia , Vancouver, British Columbia V6T 1Z2, Canada
| | - Qiang Zhang
- Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University , Beijing 100084, China
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