Articles | Volume 16, issue 6
https://doi.org/10.5194/acp-16-3865-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/acp-16-3865-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
23 Mar 2016
Research article |
| 23 Mar 2016
Oxidative potential of ambient water-soluble PM2.5 in the southeastern United States: contrasts in sources and health associations between ascorbic acid (AA) and dithiothreitol (DTT) assays
Ting Fang
School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA
Vishal Verma
Department of Civil and Environmental Engineering, University of Illinois Urbana-Champaign, Champaign, IL 61801, USA
Josephine T. Bates
School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
Joseph Abrams
Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
Mitchel Klein
Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
Matthew J. Strickland
Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
Stefanie E. Sarnat
Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
Howard H. Chang
Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
James A. Mulholland
School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
Paige E. Tolbert
Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
Armistead G. Russell
School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
Rodney J. Weber
CORRESPONDING AUTHOR
School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA
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Athanasios Nenes, Spyros N. Pandis, Rodney J. Weber, and Armistead Russell
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Anusha Priyadarshani Silva Hettiyadura, Ibrahim M. Al-Naiema, Dagen D. Hughes, Ting Fang, and Elizabeth A. Stone
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Joseph V. Puthussery, Chen Zhang, and Vishal Verma
Atmos. Meas. Tech., 11, 5767–5780, https://doi.org/10.5194/amt-11-5767-2018, https://doi.org/10.5194/amt-11-5767-2018, 2018
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Theodora Nah, Yi Ji, David J. Tanner, Hongyu Guo, Amy P. Sullivan, Nga Lee Ng, Rodney J. Weber, and L. Gregory Huey
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Hongyu Guo, Rene Otjes, Patrick Schlag, Astrid Kiendler-Scharr, Athanasios Nenes, and Rodney J. Weber
Atmos. Chem. Phys., 18, 12241–12256, https://doi.org/10.5194/acp-18-12241-2018, https://doi.org/10.5194/acp-18-12241-2018, 2018
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Theodora Nah, Hongyu Guo, Amy P. Sullivan, Yunle Chen, David J. Tanner, Athanasios Nenes, Armistead Russell, Nga Lee Ng, L. Gregory Huey, and Rodney J. Weber
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Xuan Wang, Colette L. Heald, Jiumeng Liu, Rodney J. Weber, Pedro Campuzano-Jost, Jose L. Jimenez, Joshua P. Schwarz, and Anne E. Perring
Atmos. Chem. Phys., 18, 635–653, https://doi.org/10.5194/acp-18-635-2018, https://doi.org/10.5194/acp-18-635-2018, 2018
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This work compares three methods to determine the optimal approach for quantifying the total oxidative potential (OP) of fine particles collected with filters using the dithiothreitol (DTT) assay. An automated system has been developed to facilitate the total OP measurements for use in generation of large data sets needed for epidemiology studies. The results from this study show that the water-insoluble components contribute to PM2.5 OP and the related DTT-active species are largely secondary.
Hongyu Guo, Jiumeng Liu, Karl D. Froyd, James M. Roberts, Patrick R. Veres, Patrick L. Hayes, Jose L. Jimenez, Athanasios Nenes, and Rodney J. Weber
Atmos. Chem. Phys., 17, 5703–5719, https://doi.org/10.5194/acp-17-5703-2017, https://doi.org/10.5194/acp-17-5703-2017, 2017
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Fine particle pH is linked to many environmental impacts by affecting particle concentration and composition. Predicted Pasadena, CA (CalNex campaign), PM1 pH is 1.9 and PM2.5 pH 2.7, the latter higher due to sea salts. The model predicted gas–particle partitionings of HNO3–NO3−, NH3–NH4+, and HCl–Cl− are in good agreement, verifying the model predictions. A summary of contrasting locations in the US and eastern Mediterranean shows fine particles are generally highly acidic, with pH below 3.
Wing Y. Tuet, Yunle Chen, Lu Xu, Shierly Fok, Dong Gao, Rodney J. Weber, and Nga L. Ng
Atmos. Chem. Phys., 17, 839–853, https://doi.org/10.5194/acp-17-839-2017, https://doi.org/10.5194/acp-17-839-2017, 2017
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Secondary organic aerosols (SOA) comprise a significant fraction of particulate matter (PM) and may have health implications. The water-soluble oxidative potentials of various SOA systems were determined using dithiothreitol consumption. Results from this study demonstrate that precursor identity was more influential than reaction condition in determining SOA oxidative potential and highlight a need to consider SOA contributions from anthropogenic hydrocarbons to PM-induced health effects.
Havala O. T. Pye, Benjamin N. Murphy, Lu Xu, Nga L. Ng, Annmarie G. Carlton, Hongyu Guo, Rodney Weber, Petros Vasilakos, K. Wyat Appel, Sri Hapsari Budisulistiorini, Jason D. Surratt, Athanasios Nenes, Weiwei Hu, Jose L. Jimenez, Gabriel Isaacman-VanWertz, Pawel K. Misztal, and Allen H. Goldstein
Atmos. Chem. Phys., 17, 343–369, https://doi.org/10.5194/acp-17-343-2017, https://doi.org/10.5194/acp-17-343-2017, 2017
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We use a chemical transport model to examine how organic compounds in the atmosphere interact with water present in particles. Organic compounds themselves lead to water uptake, and organic compounds interact with water associated with inorganic compounds in the rural southeast atmosphere. Including interactions of organic compounds with water requires a treatment of nonideality to more accurately represent aerosol observations during the Southern Oxidant and Aerosol Study (SOAS) 2013.
Amelia F. Longo, David J. Vine, Laura E. King, Michelle Oakes, Rodney J. Weber, Lewis Gregory Huey, Armistead G. Russell, and Ellery D. Ingall
Atmos. Chem. Phys., 16, 13389–13398, https://doi.org/10.5194/acp-16-13389-2016, https://doi.org/10.5194/acp-16-13389-2016, 2016
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New synchrotron-based techniques were applied to characterize the oxidation state and composition of sulfur in ambient aerosol and emission sources. Individual particles were found to contain surprisingly high levels of elemental sulfur, a form of sulfur found in only one of the emission sources analyzed. We also show metal sulfates as a key component of urban aerosols. These metal sulfate phases are highly soluble and are indicative of acidic processes transforming metals in the environment.
Weruka Rattanavaraha, Kevin Chu, Sri Hapsari Budisulistiorini, Matthieu Riva, Ying-Hsuan Lin, Eric S. Edgerton, Karsten Baumann, Stephanie L. Shaw, Hongyu Guo, Laura King, Rodney J. Weber, Miranda E. Neff, Elizabeth A. Stone, John H. Offenberg, Zhenfa Zhang, Avram Gold, and Jason D. Surratt
Atmos. Chem. Phys., 16, 4897–4914, https://doi.org/10.5194/acp-16-4897-2016, https://doi.org/10.5194/acp-16-4897-2016, 2016
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The mechanisms by which specific anthropogenic pollutants enhance isoprene SOA in ambient PM2.5 remain unclear. As one aspect of an investigation to examine how anthropogenic pollutants influence isoprene-derived SOA formation, high-volume PM2.5 filter samples were collected from Birmingham, AL, during the 2013 Southern Oxidant and Aerosol Study (SOAS). Isoprene SOA tracers were measured from these samples and compared to gas and aerosol data collected from the SEARCH network.
Aikaterini Bougiatioti, Panayiota Nikolaou, Iasonas Stavroulas, Giorgos Kouvarakis, Rodney Weber, Athanasios Nenes, Maria Kanakidou, and Nikolaos Mihalopoulos
Atmos. Chem. Phys., 16, 4579–4591, https://doi.org/10.5194/acp-16-4579-2016, https://doi.org/10.5194/acp-16-4579-2016, 2016
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Atmospheric aerosols and relevant parameters were measured in the eastern Mediterranean during summer and fall 2012. Submicron aerosol water can contribute up to 33 % of total mass, and 27.5 % of this can be associated with organics. Using these data, the pH of the submicron aerosols was calculated to be highly acidic, varying from 0.5 to 2.8 and independently of air masses origin. Such pH values could increase nutrient availability and thus sea water productivity of the Mediterranean Sea.
Karoline K. Johnson, Michael H. Bergin, Armistead G. Russell, and Gayle S. W. Hagler
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2015-331, https://doi.org/10.5194/amt-2015-331, 2016
Revised manuscript not accepted
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Low-cost air quality sensors were evaluated in Atlanta, GA, in Hyderabad, India and also in lab experiments. Freeway emissions were also quantified in Atlanta. The performance of these sensors were evaluated against current measurement instruments. Results show potential usefulness for these sensors in polluted areas. The ability to inexpensively measure air pollution will enable researches, citizens, and policy makers to make informed decisions to reduce health impacts from air pollution.
T. Fang, H. Guo, V. Verma, R. E. Peltier, and R. J. Weber
Atmos. Chem. Phys., 15, 11667–11682, https://doi.org/10.5194/acp-15-11667-2015, https://doi.org/10.5194/acp-15-11667-2015, 2015
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This work presented a new method of quantifying water-soluble elements in PM2.5 aqueous extracts (N~500) with an X-ray fluorescence analyzer. The results indicate that water-soluble elements had marked spatial and temporal patterns. Four sources were resolved: brake/tire wear, biomass burning, secondary formation, and mineral dust. The findings have informed studies on aerosol oxidative potential and provided insights into the health effects of water-soluble metals, especially Cu, Fe, Mn and Zn.
K. M. Cerully, A. Bougiatioti, J. R. Hite Jr., H. Guo, L. Xu, N. L. Ng, R. Weber, and A. Nenes
Atmos. Chem. Phys., 15, 8679–8694, https://doi.org/10.5194/acp-15-8679-2015, https://doi.org/10.5194/acp-15-8679-2015, 2015
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The hygroscopicity of SE US aerosol is mostly water-soluble, with a hygroscopicity that is insensitive to partial volatilization in a thermodenuder.
The most and least oxidized components of the aerosol are the most hygroscopic of organic constituents.
No clear relationship was found between organic aerosol hygroscopicity and oxygen-to-carbon ratio.
The aerosol factors covary in a way that induces the observed diurnal invariance in total organic hygroscopicity.
C. E. Ivey, H. A. Holmes, Y. T. Hu, J. A. Mulholland, and A. G. Russell
Geosci. Model Dev., 8, 2153–2165, https://doi.org/10.5194/gmd-8-2153-2015, https://doi.org/10.5194/gmd-8-2153-2015, 2015
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An integral part of air quality management is knowledge of the impact of pollutant sources on ambient concentrations of particulate matter (PM). This work presents a novel spatiotemporal source apportionment method that generates source impacts for the continental USA. Key sources presented include fossil fuel combustion, biomass burning, dust, sea salt, as well as agricultural activities, biogenics, and aircraft.
J. Liu, E. Scheuer, J. Dibb, G. S. Diskin, L. D. Ziemba, K. L. Thornhill, B. E. Anderson, A. Wisthaler, T. Mikoviny, J. J. Devi, M. Bergin, A. E. Perring, M. Z. Markovic, J. P. Schwarz, P. Campuzano-Jost, D. A. Day, J. L. Jimenez, and R. J. Weber
Atmos. Chem. Phys., 15, 7841–7858, https://doi.org/10.5194/acp-15-7841-2015, https://doi.org/10.5194/acp-15-7841-2015, 2015
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Brown carbon (BrC) is found throughout the US continental troposphere during a summer of extensive biomass burning and its prevalence relative to black carbon (BC) increases with altitude. A radiative transfer model based on direct measurements of aerosol scattering and absorption by BC and BrC shows BrC reduces top-of-atmosphere forcing by 20%. A method to estimate BrC radiative forcing efficiencies from surface-based measurements is provided.
L. Xu, S. Suresh, H. Guo, R. J. Weber, and N. L. Ng
Atmos. Chem. Phys., 15, 7307–7336, https://doi.org/10.5194/acp-15-7307-2015, https://doi.org/10.5194/acp-15-7307-2015, 2015
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Year-long comprehensive characterization of ambient aerosol was performed in both rural and urban sites in the southeastern US as part of Southeastern Center of Air Pollution and Epidemiology (SCAPE) study and Southeastern Oxidant and Aerosol Study (SOAS). Three independent methods were applied to estimate the concentration of particle-phase organic nitrates. The spatial distribution of organic aerosol is investigated by comparing simultaneous HR-ToF-AMS and ACSM measurements at different sites.
H. Guo, L. Xu, A. Bougiatioti, K. M. Cerully, S. L. Capps, J. R. Hite Jr., A. G. Carlton, S.-H. Lee, M. H. Bergin, N. L. Ng, A. Nenes, and R. J. Weber
Atmos. Chem. Phys., 15, 5211–5228, https://doi.org/10.5194/acp-15-5211-2015, https://doi.org/10.5194/acp-15-5211-2015, 2015
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Particle pH can affect many aerosol processes, including gas-particle partitioning, SOA formation, and mobilization of toxic redox metals. pH is challenging to directly measure and often improperly characterized by proxies like ion balances or molar ratios of measured aerosol ionic species. We present a detailed analysis predicting pH with a thermodynamic model, verify the prediction, and test pH sensitivity to model inputs based on data from the SOAS field campaign.
J. W. Taylor, J. D. Allan, D. Liu, M. Flynn, R. Weber, X. Zhang, B. L. Lefer, N. Grossberg, J. Flynn, and H. Coe
Atmos. Meas. Tech., 8, 1701–1718, https://doi.org/10.5194/amt-8-1701-2015, https://doi.org/10.5194/amt-8-1701-2015, 2015
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When using the SP2 to report black carbon core/shell coating thickness, the core density and refractive index must be estimated from literature values. We systematically vary the assumed parameters and the instrument calibration, and quantify the effects in the derived coatings. The technique is highly sensitive to the core refractive index but has only a minor sensitivity to the core density and coating refractive index. We identify the most appropriate values to use in future analysis.
C. J. Hennigan, J. Izumi, A. P. Sullivan, R. J. Weber, and A. Nenes
Atmos. Chem. Phys., 15, 2775–2790, https://doi.org/10.5194/acp-15-2775-2015, https://doi.org/10.5194/acp-15-2775-2015, 2015
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We show that the ion balance and molar ratio methods are unsuitable for use as aerosol pH proxies. Our recommendation is that 1) thermodynamic equilibrium models constrained by both gas and aerosol inputs run in the forward (open) mode, and 2) the phase partitioning of ammonia provides the best predictions of aerosol pH. Given the significance of acidity for numerous chemical processes in the atmosphere, the implications of this study are important and far reaching.
B. Yuan, P. R. Veres, C. Warneke, J. M. Roberts, J. B. Gilman, A. Koss, P. M. Edwards, M. Graus, W. C. Kuster, S.-M. Li, R. J. Wild, S. S. Brown, W. P. Dubé, B. M. Lerner, E. J. Williams, J. E. Johnson, P. K. Quinn, T. S. Bates, B. Lefer, P. L. Hayes, J. L. Jimenez, R. J. Weber, R. Zamora, B. Ervens, D. B. Millet, B. Rappenglück, and J. A. de Gouw
Atmos. Chem. Phys., 15, 1975–1993, https://doi.org/10.5194/acp-15-1975-2015, https://doi.org/10.5194/acp-15-1975-2015, 2015
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In this work, secondary formation of formic acid at an urban site and a site in an oil and gas production region is studied. We investigated various gas phase formation pathways of formic acid, including those recently proposed, using a box model. The contributions from aerosol-related processes, fog events and air-snow exchange to formic acid are also quantified.
T. Fang, V. Verma, H. Guo, L. E. King, E. S. Edgerton, and R. J. Weber
Atmos. Meas. Tech., 8, 471–482, https://doi.org/10.5194/amt-8-471-2015, https://doi.org/10.5194/amt-8-471-2015, 2015
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This work summarizes a newly developed semi-automated system for quantifying the oxidative potential of aerosol aqueous extracts using the dithiothreitol (DTT) assay. 500 sample analyses indicate that DTT activity in the southeast US is likely not dominated by a unique local source, and sources change with season. The unique large data set generated with the technique described in this paper allows new studies on DTT sources and investigating linkages between reactive oxygen species and health.
V. Verma, T. Fang, H. Guo, L. King, J. T. Bates, R. E. Peltier, E. Edgerton, A. G. Russell, and R. J. Weber
Atmos. Chem. Phys., 14, 12915–12930, https://doi.org/10.5194/acp-14-12915-2014, https://doi.org/10.5194/acp-14-12915-2014, 2014
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The major emission sources of the reactive oxygen species (ROS) associated with ambient particulate matter in the southeastern United States were identified. The study shows biomass burning and secondary aerosol formation as the major sources contributing to the ROS-generating capability of ambient particles. The ubiquitous nature of these two sources suggests widespread population exposures to the toxic aerosol components.
Y. You, V. P. Kanawade, J. A. de Gouw, A. B. Guenther, S. Madronich, M. R. Sierra-Hernández, M. Lawler, J. N. Smith, S. Takahama, G. Ruggeri, A. Koss, K. Olson, K. Baumann, R. J. Weber, A. Nenes, H. Guo, E. S. Edgerton, L. Porcelli, W. H. Brune, A. H. Goldstein, and S.-H. Lee
Atmos. Chem. Phys., 14, 12181–12194, https://doi.org/10.5194/acp-14-12181-2014, https://doi.org/10.5194/acp-14-12181-2014, 2014
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Amiens play important roles in atmospheric secondary aerosol formation and human health, but the fast response measurements of amines are lacking. Here we show measurements in a southeastern US forest and a moderately polluted midwestern site. Our results show that gas to particle conversion is an important process that controls ambient amine concentrations and that biomass burning is an important source of amines.
T. K. V. Nguyen, M. D. Petters, S. R. Suda, H. Guo, R. J. Weber, and A. G. Carlton
Atmos. Chem. Phys., 14, 10911–10930, https://doi.org/10.5194/acp-14-10911-2014, https://doi.org/10.5194/acp-14-10911-2014, 2014
S. H. Budisulistiorini, M. R. Canagaratna, P. L. Croteau, K. Baumann, E. S. Edgerton, M. S. Kollman, N. L. Ng, V. Verma, S. L. Shaw, E. M. Knipping, D. R. Worsnop, J. T. Jayne, R.J. Weber, and J. D. Surratt
Atmos. Meas. Tech., 7, 1929–1941, https://doi.org/10.5194/amt-7-1929-2014, https://doi.org/10.5194/amt-7-1929-2014, 2014
Y. Hu, S. Balachandran, J. E. Pachon, J. Baek, C. Ivey, H. Holmes, M. T. Odman, J. A. Mulholland, and A. G. Russell
Atmos. Chem. Phys., 14, 5415–5431, https://doi.org/10.5194/acp-14-5415-2014, https://doi.org/10.5194/acp-14-5415-2014, 2014
M. Trail, A. P. Tsimpidi, P. Liu, K. Tsigaridis, Y. Hu, A. Nenes, and A. G. Russell
Geosci. Model Dev., 6, 1429–1445, https://doi.org/10.5194/gmd-6-1429-2013, https://doi.org/10.5194/gmd-6-1429-2013, 2013
Y. Cheng, G. Engling, K.-B. He, F.-K. Duan, Y.-L. Ma, Z.-Y. Du, J.-M. Liu, M. Zheng, and R. J. Weber
Atmos. Chem. Phys., 13, 7765–7781, https://doi.org/10.5194/acp-13-7765-2013, https://doi.org/10.5194/acp-13-7765-2013, 2013
L. E. King and R. J. Weber
Atmos. Meas. Tech., 6, 1647–1658, https://doi.org/10.5194/amt-6-1647-2013, https://doi.org/10.5194/amt-6-1647-2013, 2013
T. L. Lathem, A. J. Beyersdorf, K. L. Thornhill, E. L. Winstead, M. J. Cubison, A. Hecobian, J. L. Jimenez, R. J. Weber, B. E. Anderson, and A. Nenes
Atmos. Chem. Phys., 13, 2735–2756, https://doi.org/10.5194/acp-13-2735-2013, https://doi.org/10.5194/acp-13-2735-2013, 2013
Related subject area
Subject: Aerosols | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
An attribution of the low single-scattering albedo of biomass burning aerosol over the southeastern Atlantic
Measurement report: Rapid changes of chemical characteristics and health risks for highly time resolved trace elements in PM2.5 in a typical industrial city in response to stringent clean air actions
Measurement report: Summertime fluorescence characteristics of atmospheric water-soluble organic carbon in the marine boundary layer of the western Arctic Ocean
High frequency of new particle formation events driven by summer monsoon in the central Tibetan Plateau, China
Chemical precursors of new particle formation in coastal New Zealand
Insights into the single-particle composition, size, mixing state, and aspect ratio of freshly emitted mineral dust from field measurements in the Moroccan Sahara using electron microscopy
Seasonal variation of aerosol iron solubility in coarse and fine particles at an inland city in northwestern China
Unambiguous identification of N-containing oxygenated organic molecules using a chemical-ionization Orbitrap (CI-Orbitrap) in an eastern Chinese megacity
Estimating hub-height wind speed based on a machine learning algorithm: implications for wind energy assessment
Characteristics and degradation of organic aerosols from cooking sources based on hourly observations of organic molecular markers in urban environments
Characteristics of particulate-bound n-alkanes indicating sources of PM2.5 in Beijing, China
Characterization of volatile organic compounds and submicron organic aerosol in a traffic environment
Non-volatile marine and non-refractory continental sources of particle-phase amine during the North Atlantic Aerosols and Marine Ecosystems Study (NAAMES)
Effects of transport on a biomass burning plume from Indochina during EMeRGe-Asia identified by WRF-Chem
The shifting of secondary inorganic aerosol formation mechanisms during haze aggravation: the decisive role of aerosol liquid water
Collective geographical ecoregions and precursor sources driving Arctic new particle formation
Measurement report: Chemical components and 13C and 15N isotope ratios of fine aerosols over Tianjin, North China: year-round observations
Impact of biogenic secondary organic aerosol (SOA) loading on the molecular composition of wintertime PM2.5 in urban Tianjin: an insight from Fourier transform ion cyclotron resonance mass spectrometry
Impacts of biomass burning and photochemical processing on the light absorption of brown carbon in the southeastern Tibetan Plateau
Fates of secondary organic aerosols in the atmosphere identified from compound-specific dual-carbon isotope analysis of oxalic acid
Vertical profiles of volatile organic compounds and fine particles in atmospheric air by using aerial drone with miniaturized samplers and portable devices
Measurement report: Aerosol vertical profiles over the western North Atlantic Ocean during the North Atlantic Aerosols and Marine Ecosystems Study (NAAMES)
Characteristics of fine particle matter at the top of Shanghai Tower
Measurement report: Abundance and fractional solubilities of aerosol metals in urban Hong Kong – insights into factors that control aerosol metal dissolution in an urban site in South China
Measurement report: Intensive biomass burning emissions and rapid nitrate formation drive severe haze formation in the Sichuan Basin, China – insights from aerosol mass spectrometry
African smoke particles act as cloud condensation nuclei in the wintertime tropical North Atlantic boundary layer over Barbados
Measurement report: Changes in light absorption and molecular composition of water-soluble humic-like substances during a winter haze bloom-decay process in Guangzhou, China
Varying chiral ratio of pinic acid enantiomers above the Amazon rainforest
Impact of aging on the sources, volatility, and viscosity of organic aerosols in Chinese outflows
Biogenic and anthropogenic sources of isoprene and monoterpenes and their secondary organic aerosol in Delhi, India
Insights into characteristics and formation mechanisms of secondary organic aerosols in Guangzhou urban area
Amino acids, carbohydrates and lipids in the tropical oligotrophic Atlantic Ocean: Sea-to-air transfer and atmospheric in situ formation
Different physicochemical behaviors of nitrate and ammonium during transport: a case study on Mt. Hua, China
A method for using stationary networks to observe long-term trends of on-road emission factors of primary aerosol from heavy-duty vehicles
Atmospheric particle abundance and sea salt aerosol observations in the springtime Arctic: a focus on blowing snow and leads
Chromophores and chemical composition of brown carbon characterized at an urban kerbside by excitation–emission spectroscopy and mass spectrometry
Measurement report: Contrasting elevation-dependent light absorption by black and brown carbon: lessons from in situ measurements from the highly polluted Sichuan Basin to the pristine Tibetan Plateau
Long-term declines in atmospheric nitrogen and sulfur deposition reduce critical loads exceedances at multiple Canadian rural sites, 2000–2018
Composition and mixing state of Arctic aerosol and cloud residual particles from long-term single-particle observations at Zeppelin Observatory, Svalbard
A meteorological overview of the ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS) campaign over the southeastern Atlantic during 2016–2018: Part 2 – Daily and synoptic characteristics
Long-range transported pollution from the Middle East and its impact on carbonaceous aerosol sources over Cyprus
Measurement report: Characterization of sugars and amino acids in atmospheric fine particulates and their relationship to local primary sources
Organic enrichment in droplet residual particles relative to out of cloud over the northwestern Atlantic: analysis of airborne ACTIVATE data
Long-term trends and drivers of aerosol pH in eastern China
Potential underestimation of ambient brown carbon absorption based on the methanol extraction method and its impacts on source analysis
Contributions of primary sources to submicron organic aerosols in Delhi, India
Examination of brown carbon absorption from wildfires in the western US during the WE-CAN study
Source apportionment and evolution of N-containing aerosols at a rural cloud forest in Taiwan by isotope analysis
Measurement report: Characterisation and sources of the secondary organic carbon in a Chinese megacity over 5 years from 2016 to 2020
Exploring the inorganic composition of the Asian Tropopause Aerosol Layer using medium-duration balloon flights
Amie Dobracki, Paquita Zuidema, Steven G. Howell, Pablo Saide, Steffen Freitag, Allison C. Aiken, Sharon P. Burton, Arthur J. Sedlacek III, Jens Redemann, and Robert Wood
Atmos. Chem. Phys., 23, 4775–4799, https://doi.org/10.5194/acp-23-4775-2023, https://doi.org/10.5194/acp-23-4775-2023, 2023
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Southern Africa produces approximately one-third of the world’s carbon from fires. The thick smoke layer can flow westward, interacting with the southeastern Atlantic cloud deck. The net radiative impact can alter regional circulation patterns, impacting rainfall over Africa. We find that the smoke is highly absorbing of sunlight, mostly because it contains more black carbon than smoke over the Northern Hemisphere.
Rui Li, Yining Gao, Yubao Chen, Meng Peng, Weidong Zhao, Gehui Wang, and Jiming Hao
Atmos. Chem. Phys., 23, 4709–4726, https://doi.org/10.5194/acp-23-4709-2023, https://doi.org/10.5194/acp-23-4709-2023, 2023
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A random forest model was used to isolate the effects of emission and meteorology to trace elements in PM2.5 in Tangshan. The results suggested that control measures facilitated decreases of Ga, Co, Pb, Zn, and As, due to the strict implementation of coal-to-gas strategies and optimisation of industrial structure and layout. However, the deweathered levels of Ca, Cr, and Fe only displayed minor decreases, indicating that ferrous metal smelting and vehicle emission controls should be enhanced.
Jinyoung Jung, Yuzo Miyazaki, Jin Hur, Yun Kyung Lee, Mi Hae Jeon, Youngju Lee, Kyoung-Ho Cho, Hyun Young Chung, Kitae Kim, Jung-Ok Choi, Catherine Lalande, Joo-Hong Kim, Taejin Choi, Young Jun Yoon, Eun Jin Yang, and Sung-Ho Kang
Atmos. Chem. Phys., 23, 4663–4684, https://doi.org/10.5194/acp-23-4663-2023, https://doi.org/10.5194/acp-23-4663-2023, 2023
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This study examined the summertime fluorescence properties of water-soluble organic carbon (WSOC) in aerosols over the western Arctic Ocean. We found that the WSOC in fine-mode aerosols in coastal areas showed a higher polycondensation degree and aromaticity than in sea-ice-covered areas. The fluorescence properties of atmospheric WSOC in the summertime marine Arctic boundary can improve our understanding of the WSOC chemical and biological linkages at the ocean–sea-ice–atmosphere interface.
Lizi Tang, Min Hu, Dongjie Shang, Xin Fang, Jianjiong Mao, Wanyun Xu, Jiacheng Zhou, Weixiong Zhao, Yaru Wang, Chong Zhang, Yingjie Zhang, Jianlin Hu, Limin Zeng, Chunxiang Ye, Song Guo, and Zhijun Wu
Atmos. Chem. Phys., 23, 4343–4359, https://doi.org/10.5194/acp-23-4343-2023, https://doi.org/10.5194/acp-23-4343-2023, 2023
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There was an evident distinction in the frequency of new particle formation (NPF) events at Nam Co station on the Tibetan Plateau: 15 % in pre-monsoon season and 80 % in monsoon season. The frequent NPF events in monsoon season resulted from the higher frequency of southerly air masses, which brought the organic precursors to participate in the NPF process. It increased the amount of aerosol and CCN compared with those in pre-monsoon season, which may markedly affect earth's radiation balance.
Maija Peltola, Clémence Rose, Jonathan V. Trueblood, Sally Gray, Mike Harvey, and Karine Sellegri
Atmos. Chem. Phys., 23, 3955–3983, https://doi.org/10.5194/acp-23-3955-2023, https://doi.org/10.5194/acp-23-3955-2023, 2023
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We measured the chemical composition of ambient ions at a coastal New Zealand site and connected these data with aerosol size distribution data to study the chemical precursors of new particle formation at the site. Our results showed that iodine oxides and sulfur species were important for particle formation in marine air, while in land-influenced air sulfuric acid and organics were connected to new particle formation events.
Agnesh Panta, Konrad Kandler, Andres Alastuey, Cristina González-Flórez, Adolfo González-Romero, Martina Klose, Xavier Querol, Cristina Reche, Jesús Yus-Díez, and Carlos Pérez García-Pando
Atmos. Chem. Phys., 23, 3861–3885, https://doi.org/10.5194/acp-23-3861-2023, https://doi.org/10.5194/acp-23-3861-2023, 2023
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Desert dust is a major aerosol component of the Earth system and affects the climate. Dust properties are influenced by particle size, mineralogy, shape, and mixing state. This work characterizes freshly emitted individual mineral dust particles from a major source region using electron microscopy. Our new insights into critical particle-specific information will contribute to better constraining climate models that consider mineralogical variations in their representation of the dust cycle.
Huanhuan Zhang, Rui Li, Chengpeng Huang, Xiaofei Li, Shuwei Dong, Fu Wang, Tingting Li, Yizhu Chen, Guohua Zhang, Yan Ren, Qingcai Chen, Ru-jin Huang, Siyu Chen, Tao Xue, Xinming Wang, and Mingjin Tang
Atmos. Chem. Phys., 23, 3543–3559, https://doi.org/10.5194/acp-23-3543-2023, https://doi.org/10.5194/acp-23-3543-2023, 2023
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This work investigated the seasonal variation of aerosol Fe solubility for coarse and fine particles in Xi’an, a megacity in northwestern China severely affected by anthropogenic emission and desert dust aerosol. In addition, we discussed in depth what controlled aerosol Fe solubility at different seasons for coarse and fine particles.
Yiqun Lu, Yingge Ma, Dan Dan Huang, Shengrong Lou, Sheng'ao Jing, Yaqin Gao, Hongli Wang, Yanjun Zhang, Hui Chen, Yunhua Chang, Naiqiang Yan, Jianmin Chen, Christian George, Matthieu Riva, and Cheng Huang
Atmos. Chem. Phys., 23, 3233–3245, https://doi.org/10.5194/acp-23-3233-2023, https://doi.org/10.5194/acp-23-3233-2023, 2023
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N-containing oxygenated organic molecules have been identified as important precursors of aerosol particles. We used an ultra-high-resolution mass spectrometer coupled with an online sample inlet to accurately measure their molecular composition, concentration level and variation patterns. We show their formation process and influencing factors in a Chinese megacity involving various volatile organic compound precursors and atmospheric oxidants, and we highlight the influence of PM2.5 episodes.
Boming Liu, Xin Ma, Jianping Guo, Hui Li, Shikuan Jin, Yingying Ma, and Wei Gong
Atmos. Chem. Phys., 23, 3181–3193, https://doi.org/10.5194/acp-23-3181-2023, https://doi.org/10.5194/acp-23-3181-2023, 2023
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Wind energy is one of the most essential clean and renewable forms of energy in today’s world. However, the traditional power law method generally estimates the hub-height wind speed by assuming a constant exponent between surface and hub-height wind speeds. This inevitably leads to significant uncertainties in estimating the wind speed profile. To minimize the uncertainties, we here use a machine learning algorithm known as random forest to estimate the wind speed at hub height.
Rui Li, Kun Zhang, Qing Li, Liumei Yang, Shunyao Wang, Zhiqiang Liu, Xiaojuan Zhang, Hui Chen, Yanan Yi, Jialiang Feng, Qiongqiong Wang, Ling Huang, Wu Wang, Yangjun Wang, Jian Zhen Yu, and Li Li
Atmos. Chem. Phys., 23, 3065–3081, https://doi.org/10.5194/acp-23-3065-2023, https://doi.org/10.5194/acp-23-3065-2023, 2023
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Molecular markers in organic aerosol (OA) provide specific source information on PM2.5, and the contribution of cooking emissions to OA is significant, especially in urban environments. This study investigates the variation in concentrations and oxidative degradation of fatty acids and corresponding oxidation products in ambient air, which can be a guide for the refinement of aerosol source apportionment and provide scientific support for the development of emission source control policies.
Jiyuan Yang, Guoyang Lei, Chang Liu, Yutong Wu, Kai Hu, Jinfeng Zhu, Junsong Bao, Weili Lin, and Jun Jin
Atmos. Chem. Phys., 23, 3015–3029, https://doi.org/10.5194/acp-23-3015-2023, https://doi.org/10.5194/acp-23-3015-2023, 2023
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The characteristics of n-alkanes and the contributions of various sources of PM2.5 in the atmosphere in Beijing were studied. There were marked seasonal and diurnal differences in the n-alkane concentrations (p<0.01). Particulate-bound n-alkanes were supplied by anthropogenic and biogenic sources; fossil fuel combustion was the dominant contributor. Vehicle exhausts strongly affect PM2.5 pollution. Controlling vehicle exhaust emissions is key to control n-alkane and PM2.5 pollution in Beijing.
Sanna Saarikoski, Heidi Hellén, Arnaud P. Praplan, Simon Schallhart, Petri Clusius, Jarkko V. Niemi, Anu Kousa, Toni Tykkä, Rostislav Kouznetsov, Minna Aurela, Laura Salo, Topi Rönkkö, Luis M. F. Barreira, Liisa Pirjola, and Hilkka Timonen
Atmos. Chem. Phys., 23, 2963–2982, https://doi.org/10.5194/acp-23-2963-2023, https://doi.org/10.5194/acp-23-2963-2023, 2023
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This study elucidates properties and sources of volatile organic compounds (VOCs) and organic aerosol (OA) in a traffic environment. Anthropogenic VOCs (aVOCs) were clearly higher than biogenic VOCs (bVOCs), but bVOCs produced a larger portion of oxidation products. OA consisted mostly of oxygenated OA, representing secondary OA (SOA). SOA was partly associated with bVOCs, but it was also related to long-range transport. Primary OA originated mostly from traffic.
Veronica Z. Berta, Lynn M. Russell, Derek J. Price, Chia-Li Chen, Alex K. Y. Lee, Patricia K. Quinn, Timothy S. Bates, Thomas G. Bell, and Michael J. Behrenfeld
Atmos. Chem. Phys., 23, 2765–2787, https://doi.org/10.5194/acp-23-2765-2023, https://doi.org/10.5194/acp-23-2765-2023, 2023
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Amines are compounds emitted from a variety of marine and continental sources and were measured by aerosol mass spectrometry and Fourier transform infrared spectroscopy during the North Atlantic Aerosols and Marine Ecosystems Study (NAAMES) cruises. Secondary continental and primary marine sources of amines were identified by comparisons to tracers. The results show that the two methods are complementary for investigating amines in the marine environment.
Chuan-Yao Lin, Wan-Chin Chen, Yi-Yun Chien, Charles C. K. Chou, Chian-Yi Liu, Helmut Ziereis, Hans Schlager, Eric Förster, Florian Obersteiner, Ovid O. Krüger, Bruna A. Holanda, Mira L. Pöhlker, Katharina Kaiser, Johannes Schneider, Birger Bohn, Klaus Pfeilsticker, Benjamin Weyland, Maria Dolores Andrés Hernández, and John P. Burrows
Atmos. Chem. Phys., 23, 2627–2647, https://doi.org/10.5194/acp-23-2627-2023, https://doi.org/10.5194/acp-23-2627-2023, 2023
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During the EMeRGe campaign in Asia, atmospheric pollutants were measured on board the HALO aircraft. The WRF-Chem model was employed to evaluate the biomass burning (BB) plume transported from Indochina and its impact on the downstream areas. The combination of BB aerosol enhancement with cloud water resulted in a reduction in incoming shortwave radiation at the surface in southern China and the East China Sea, which potentially has significant regional climate implications.
Fei Xie, Yue Su, Yongli Tian, Yanju Shi, Xingjun Zhou, Peng Wang, Ruihong Yu, Wei Wang, Jiang He, Jinyuan Xin, and Changwei Lü
Atmos. Chem. Phys., 23, 2365–2378, https://doi.org/10.5194/acp-23-2365-2023, https://doi.org/10.5194/acp-23-2365-2023, 2023
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This work finds the shifting of secondary inorganic aerosol formation mechanisms during haze aggravation and explains the decisive role of aerosol liquid water on a broader scale (~ 500 μg m3) in an ammonia-rich atmosphere based on the in situ high-resolution online monitoring datasets.
James Brean, David C. S. Beddows, Roy M. Harrison, Congbo Song, Peter Tunved, Johan Ström, Radovan Krejci, Eyal Freud, Andreas Massling, Henrik Skov, Eija Asmi, Angelo Lupi, and Manuel Dall'Osto
Atmos. Chem. Phys., 23, 2183–2198, https://doi.org/10.5194/acp-23-2183-2023, https://doi.org/10.5194/acp-23-2183-2023, 2023
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Our results emphasize how understanding the geographical variation in surface types across the Arctic is key to understanding secondary aerosol sources. We provide a harmonised analysis of new particle formation across the Arctic.
Zhichao Dong, Chandra Mouli Pavuluri, Zhanjie Xu, Yu Wang, Peisen Li, Pingqing Fu, and Cong-Qiang Liu
Atmos. Chem. Phys., 23, 2119–2143, https://doi.org/10.5194/acp-23-2119-2023, https://doi.org/10.5194/acp-23-2119-2023, 2023
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This study has provided comprehensive baseline data of carbonaceous and inorganic aerosols as well as their isotope ratios in the Tianjin region, North China, found that Tianjin aerosols were derived from coal combustion, biomass burning and photochemical reactions of VOCs, and also implied that the Tianjin aerosols were more aged during long-range atmospheric transport in summer via carbonaceous and isotope data analysis.
Shujun Zhong, Shuang Chen, Junjun Deng, Yanbing Fan, Qiang Zhang, Qiaorong Xie, Yulin Qi, Wei Hu, Libin Wu, Xiaodong Li, Chandra Mouli Pavuluri, Jialei Zhu, Xin Wang, Di Liu, Xiaole Pan, Yele Sun, Zifa Wang, Yisheng Xu, Haijie Tong, Hang Su, Yafang Cheng, Kimitaka Kawamura, and Pingqing Fu
Atmos. Chem. Phys., 23, 2061–2077, https://doi.org/10.5194/acp-23-2061-2023, https://doi.org/10.5194/acp-23-2061-2023, 2023
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This study investigated the role of the secondary organic aerosol (SOA) loading on the molecular composition of wintertime urban aerosols by ultrahigh-resolution mass spectrometry. Results demonstrate that the SOA loading is an important factor associated with the oxidation degree, nitrate group content, and chemodiversity of nitrooxy–organosulfates. Our study also found that the hydrolysis of nitrooxy–organosulfates is a possible pathway for the formation of organosulfates.
Jie Tian, Qiyuan Wang, Yongyong Ma, Jin Wang, Yongming Han, and Junji Cao
Atmos. Chem. Phys., 23, 1879–1892, https://doi.org/10.5194/acp-23-1879-2023, https://doi.org/10.5194/acp-23-1879-2023, 2023
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We investigated the light absorption properties of brown carbon (BrC) in the Tibetan Plateau (TP). BrC made a substantial contribution to the submicron aerosol absorption, which is related to the cross-border transport of biomass burning emission and secondary aerosol from Southeast Asia. The radiative effect of BrC was half that of black carbon, which can remarkably affect the radiative balance of the TP.
Buqing Xu, Jiao Tang, Tiangang Tang, Shizhen Zhao, Guangcai Zhong, Sanyuan Zhu, Jun Li, and Gan Zhang
Atmos. Chem. Phys., 23, 1565–1578, https://doi.org/10.5194/acp-23-1565-2023, https://doi.org/10.5194/acp-23-1565-2023, 2023
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We analyzed compound-specific dual-carbon isotope signatures (Δ14C and δ13C) of dominant secondary organic aerosol (SOA) tracer molecules (i.e., oxalic acid) to investigate the fates of SOAs in the atmosphere at five emission hotspots in China. The results indicated that SOA carbon sources and chemical processes producing SOAs vary spatially and seasonally, and these variations need to be included in Chinese climate projection models and air quality management practices.
Eka Dian Pusfitasari, Jose Ruiz-Jimenez, Aleksi Tiusanen, Markus Suuronen, Jesse Haataja, Juha Kangasluoma, Krista Luoma, Tuukka Petäjä, Matti Jussila, Kari Hartonen, and Marja-Liisa Riekkola
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2023-40, https://doi.org/10.5194/acp-2023-40, 2023
Revised manuscript accepted for ACP
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A miniaturized air sampling-drone system was successfully applied for the collection of volatile organic compounds (VOCs) and for the measurement of black carbon (BC) and total particle number concentrations in atmospheric air. Here we report, for the first time, the vertical profiles of BC and aerosol number concentrations above the boreal forest in Hyytiälä (Finland) at high altitudes close to the boundary layer in autumn 2021. VOC composition with its distribution was studied as well.
Francesca Gallo, Kevin J. Sanchez, Bruce E. Anderson, Ryan Bennett, Matthew D. Brown, Ewan C. Crosbie, Chris Hostetler, Carolyn Jordan, Melissa Yang Martin, Claire E. Robinson, Lynn M. Russell, Taylor J. Shingler, Michael A. Shook, Kenneth L. Thornhill, Elizabeth B. Wiggins, Edward L. Winstead, Armin Wisthaler, Luke D. Ziemba, and Richard H. Moore
Atmos. Chem. Phys., 23, 1465–1490, https://doi.org/10.5194/acp-23-1465-2023, https://doi.org/10.5194/acp-23-1465-2023, 2023
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We integrate in situ ship- and aircraft-based measurements of aerosol, trace gases, and meteorological parameters collected during the NASA North Atlantic Aerosols and Marine Ecosystems Study (NAAMES) field campaigns in the western North Atlantic Ocean region. A comprehensive characterization of the vertical profiles of aerosol properties under different seasonal regimes is provided for improving the understanding of aerosol key processes and aerosol–cloud interactions in marine regions.
Changqin Yin, Jianming Xu, Wei Gao, Liang Pan, Yixuan Gu, Qingyan Fu, and Fan Yang
Atmos. Chem. Phys., 23, 1329–1343, https://doi.org/10.5194/acp-23-1329-2023, https://doi.org/10.5194/acp-23-1329-2023, 2023
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The particle matter (PM2.5) at the top of the 632 m high Shanghai Tower was found to be higher than the surface from June to October due to unexpected larger PM2.5 levels during early to middle afternoon at Shanghai Tower. We suppose the significant chemical production of secondary species existed in the mid-upper planetary boundary layer. We found a high nitrate concentration at the tower site for both daytime and nighttime in winter, implying efficient gas-phase and heterogeneous formation.
Junwei Yang, Lan Ma, Xiao He, Wing Chi Au, Yanhao Miao, Wen-Xiong Wang, and Theodora Nah
Atmos. Chem. Phys., 23, 1403–1419, https://doi.org/10.5194/acp-23-1403-2023, https://doi.org/10.5194/acp-23-1403-2023, 2023
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Water-soluble metals play key roles in human health and atmospheric processes. We report the seasonal abundance and fractional solubilities of different metals in aerosols collected in urban Hong Kong as well as the key factors that modulated solubilities of the various metals in fine aerosols. Our results highlight the dual roles (i.e., acidifying the aerosol particle and providing a liquid reaction medium) that sulfate plays in the acid dissolution of metals in fine aerosols in Hong Kong.
Zhier Bao, Xinyi Zhang, Qing Li, Jiawei Zhou, Guangming Shi, Li Zhou, Fumo Yang, Shaodong Xie, Dan Zhang, Chongzhi Zhai, Zhenliang Li, Chao Peng, and Yang Chen
Atmos. Chem. Phys., 23, 1147–1167, https://doi.org/10.5194/acp-23-1147-2023, https://doi.org/10.5194/acp-23-1147-2023, 2023
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We characterised non-refractory fine particulate matter (PM2.5) during winter in the Sichuan Basin (SCB), Southwest China. The factors driving severe aerosol pollution were revealed, highlighting the importance of rapid nitrate formation and intensive biomass burning. Nitrate was primarily formed through gas-phase oxidation during daytime and aqueous-phase oxidation during nighttime. Controlling nitrate and biomass burning will benefit the mitigation of haze formation in the SCB.
Haley M. Royer, Mira L. Pöhlker, Ovid Krüger, Edmund Blades, Peter Sealy, Nurun Nahar Lata, Zezhen Cheng, Swarup China, Andrew P. Ault, Patricia K. Quinn, Paquita Zuidema, Christopher Pöhlker, Ulrich Pöschl, Meinrat Andreae, and Cassandra J. Gaston
Atmos. Chem. Phys., 23, 981–998, https://doi.org/10.5194/acp-23-981-2023, https://doi.org/10.5194/acp-23-981-2023, 2023
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This paper presents atmospheric particle chemical composition and measurements of aerosol water uptake properties collected at Ragged Point, Barbados, during the winter of 2020. The result of this study indicates the importance of small African smoke particles for cloud droplet formation in the tropical North Atlantic and highlights the large spatial and temporal pervasiveness of smoke over the Atlantic Ocean.
Chunlin Zou, Tao Cao, Meiju Li, Jianzhong Song, Bin Jiang, Wanglu Jia, Jun Li, Xiang Ding, Zhiqiang Yu, Gan Zhang, and Ping'an Peng
Atmos. Chem. Phys., 23, 963–979, https://doi.org/10.5194/acp-23-963-2023, https://doi.org/10.5194/acp-23-963-2023, 2023
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In this study, PM2.5 samples were obtained during a winter haze event in Guangzhou, China, and light absorption and molecular composition of humic-like substances (HULIS) were investigated by UV–Vis spectrophotometry and ultrahigh-resolution mass spectrometry. The findings obtained present some differences from the results reported in other regions of China and significantly enhanced our understanding of HULIS evolution during haze bloom-decay processes in the subtropic region of southern China.
Denis Leppla, Nora Zannoni, Leslie Kremper, Jonathan Williams, Christopher Pöhlker, Marta Sá, Maria Christina Solci, and Thorsten Hoffmann
Atmos. Chem. Phys., 23, 809–820, https://doi.org/10.5194/acp-23-809-2023, https://doi.org/10.5194/acp-23-809-2023, 2023
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Chiral chemodiversity plays a critical role in biochemical processes such as insect and plant communication. Here we report on the measurement of chiral-specified secondary organic aerosol in the Amazon rainforest. The results show that the chiral ratio is mainly determined by large-scale emission processes. Characteristic emissions of chiral aerosol precursors from different forest ecosystems can thus provide large-scale information on different biogenic sources via chiral particle analysis.
Tingting Feng, Yingkun Wang, Weiwei Hu, Ming Zhu, Wei Song, Wei Chen, Yanyan Sang, Zheng Fang, Wei Deng, Hua Fang, Xu Yu, Cheng Wu, Bin Yuan, Shan Huang, Min Shao, Xiaofeng Huang, Lingyan He, Young Ro Lee, Lewis Gregory Huey, Francesco Canonaco, Andre S. H. Prevot, and Xinming Wang
Atmos. Chem. Phys., 23, 611–636, https://doi.org/10.5194/acp-23-611-2023, https://doi.org/10.5194/acp-23-611-2023, 2023
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To investigate the impact of aging processes on organic aerosols (OA), we conducted a comprehensive field study at a continental remote site using an on-line mass spectrometer. The results show that OA in the Chinese outflows were strongly influenced by upwind anthropogenic emissions. The aging processes can significantly decrease the OA volatility and result in a varied viscosity of OA under different circumstances, signifying the complex physiochemical properties of OA in aged plumes.
Daniel J. Bryant, Beth S. Nelson, Stefan J. Swift, Sri Hapsari Budisulistiorini, Will S. Drysdale, Adam R. Vaughan, Mike J. Newland, James R. Hopkins, James M. Cash, Ben Langford, Eiko Nemitz, W. Joe F. Acton, C. Nicholas Hewitt, Tuhin Mandal, Bhola R. Gurjar, Shivani, Ranu Gadi, James D. Lee, Andrew R. Rickard, and Jacqueline F. Hamilton
Atmos. Chem. Phys., 23, 61–83, https://doi.org/10.5194/acp-23-61-2023, https://doi.org/10.5194/acp-23-61-2023, 2023
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This paper investigates the sources of isoprene and monoterpene compounds and their particulate-phase oxidation products in Delhi, India. This was done to improve our understanding of the sources, concentrations, and fate of volatile emissions in megacities. By studying the chemical composition of offline filter samples, we report that a significant share of the oxidised organic aerosol in Delhi is from isoprene and monoterpenes. This has implications for human health and policy development.
Miaomiao Zhai, Ye Kuang, Li Liu, Yao He, Biao Luo, Wanyun Xu, Jiangchuan Tao, Yu Zou, Fei Li, Changqin Yin, Chunhui Li, Hanbing Xu, and Xuejiao Deng
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-807, https://doi.org/10.5194/acp-2022-807, 2022
Revised manuscript accepted for ACP
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Using year-long aerosol mass spectrometer measurements, roles of secondary organic aerosols (SOA) during haze formations in urban area of southern China were systematically analyzed. Almost all severe haze events were accompanied by continuous daytime and nighttime SOA formations, whereas coordinated gas-phase photochemistry and aqueous-phase reactions likely played significant roles in quick daytime SOA formations, and nitrate radical play significant roles in nighttime SOA formations.
Manuela van Pinxteren, Sebastian Zeppenfeld, Khanneh Wadinga Fomba, Nadja Triesch, Sanja Frka, and Hartmut Herrmann
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-832, https://doi.org/10.5194/acp-2022-832, 2022
Preprint under review for ACP
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Important marine organic carbon compounds were identified in the Atlantic Ocean and marine aerosol particles. These compounds were strongly enriched in the atmosphere. Their enrichment was, however, not solely explained with sea-to-air transfer but also via atmospheric in situ formation. The identified compounds constituted about 50 % of the organic carbon on the aerosol particles and a pronounced coupling between ocean and atmosphere for this oligotrophic region could be concluded.
Can Wu, Cong Cao, Jianjun Li, Shaojun Lv, Jin Li, Xiaodi Liu, Si Zhang, Shijie Liu, Fan Zhang, Jingjing Meng, and Gehui Wang
Atmos. Chem. Phys., 22, 15621–15635, https://doi.org/10.5194/acp-22-15621-2022, https://doi.org/10.5194/acp-22-15621-2022, 2022
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Over the past decade, the relative abundance of NH4NO3 in aerosol has been enhanced in most urban areas of China, which profoundly affects the PM2.5 pollution episodes. Our work finds that fine-particle nitrate and ammonium exhibited distinct, different physicochemical behaviors in the aerosol aging process.
Helen L. Fitzmaurice and Ronald C. Cohen
Atmos. Chem. Phys., 22, 15403–15411, https://doi.org/10.5194/acp-22-15403-2022, https://doi.org/10.5194/acp-22-15403-2022, 2022
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We develop a novel method for finding heavy-duty vehicle (HDV) emission factors (g PM kg fuel) using regulatory sensor networks and publicly available traffic data. We find that particulate matter emission factors have decreased by a factor of ~ 9 in the past decade in the San Francisco Bay area. Because of the wide availability of similar data sets across the USA and globally, this method could be applied to other settings to understand long-term trends and regional differences in HDV emissions.
Qianjie Chen, Jessica A. Mirrielees, Sham Thanekar, Nicole A. Loeb, Rachel M. Kirpes, Lucia M. Upchurch, Anna J. Barget, Nurun Nahar Lata, Angela R. W. Raso, Stephen M. McNamara, Swarup China, Patricia K. Quinn, Andrew P. Ault, Aaron Kennedy, Paul B. Shepson, Jose D. Fuentes, and Kerri A. Pratt
Atmos. Chem. Phys., 22, 15263–15285, https://doi.org/10.5194/acp-22-15263-2022, https://doi.org/10.5194/acp-22-15263-2022, 2022
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During a spring field campaign in the coastal Arctic, ultrafine particles were enhanced during high wind speeds, and coarse-mode particles were reduced during blowing snow. Calculated periods blowing snow were overpredicted compared to observations. Sea spray aerosols produced by sea ice leads affected the composition of aerosols and snowpack. An improved understanding of aerosol emissions from leads and blowing snow is critical for predicting the future climate of the rapidly warming Arctic.
Feng Jiang, Junwei Song, Jonas Bauer, Linyu Gao, Magdalena Vallon, Reiner Gebhardt, Thomas Leisner, Stefan Norra, and Harald Saathoff
Atmos. Chem. Phys., 22, 14971–14986, https://doi.org/10.5194/acp-22-14971-2022, https://doi.org/10.5194/acp-22-14971-2022, 2022
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We studied brown carbon aerosol during typical summer and winter periods in downtown Karlsruhe in southwestern Germany. The chromophore and chemical composition of brown carbon was determined by excitation–emission spectroscopy and mass spectrometry. The chromophore types and sources were substantially different in winter and summer. Humic-like chromophores of different degrees of oxidation dominated and were associated with molecules of different molecular weight and nitrogen content.
Suping Zhao, Shaofeng Qi, Ye Yu, Shichang Kang, Longxiang Dong, Jinbei Chen, and Daiying Yin
Atmos. Chem. Phys., 22, 14693–14708, https://doi.org/10.5194/acp-22-14693-2022, https://doi.org/10.5194/acp-22-14693-2022, 2022
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Light absorption by aerosols is poorly understood at the eastern slope of the Tibetan Plateau (TP). We conducted the first in situ PM1 chemical measurements from the polluted Sichuan Basin to the eastern TP. A contrasting changes in mass absorption efficiency of black and brown carbon with altitude is found due to source differences. This study contributes to the understanding of the difference in light absorption by carbon with altitude, from the polluted basins to the pristine TP.
Irene Cheng, Leiming Zhang, Zhuanshi He, Hazel Cathcart, Daniel Houle, Amanda Cole, Jian Feng, Jason O'Brien, Anne Marie Macdonald, Julian Aherne, and Jeffrey Brook
Atmos. Chem. Phys., 22, 14631–14656, https://doi.org/10.5194/acp-22-14631-2022, https://doi.org/10.5194/acp-22-14631-2022, 2022
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Nitrogen (N) and sulfur (S) deposition decreased significantly at 14 Canadian sites during 2000–2018. The greatest decline was observed in southeastern Canada owing to regional SO2 and NOx reductions. Wet deposition was more important than dry deposition, comprising 71–95 % of total N and 45–89 % of total S deposition. While critical loads (CLs) were exceeded at a few sites in the early 2000s, acidic deposition declined below CLs after 2012, which signifies recovery from legacy acidification.
Kouji Adachi, Yutaka Tobo, Makoto Koike, Gabriel Freitas, Paul Zieger, and Radovan Krejci
Atmos. Chem. Phys., 22, 14421–14439, https://doi.org/10.5194/acp-22-14421-2022, https://doi.org/10.5194/acp-22-14421-2022, 2022
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Ambient aerosol and cloud residual particles in the fine mode were collected at Zeppelin Observatory in Svalbard and were analyzed using transmission electron microscopy. Fractions of mineral dust and sea salt particles increased in cloud residual samples collected at ambient temperatures below 0 °C. This study highlights the variety of aerosol and cloud residual particle compositions and mixing states that influence or are influenced by aerosol–cloud interactions in Arctic low-level clouds.
Ju-Mee Ryoo, Leonhard Pfister, Rei Ueyama, Paquita Zuidema, Robert Wood, Ian Chang, and Jens Redemann
Atmos. Chem. Phys., 22, 14209–14241, https://doi.org/10.5194/acp-22-14209-2022, https://doi.org/10.5194/acp-22-14209-2022, 2022
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The variability in the meteorological fields during each deployment is highly modulated at a daily to synoptic timescale. This paper, along with part 1, the climatological overview paper, provides a meteorological context for interpreting the airborne measurements gathered during the three ORACLES deployments. This study supports related studies focusing on the detailed investigation of the processes controlling stratocumulus decks, aerosol lifting, transport, and their interactions.
Aliki Christodoulou, Iasonas Stavroulas, Mihalis Vrekoussis, Maximillien Desservettaz, Michael Pikridas, Elie Bimenyimana, Matic Ivančič, Martin Rigler, Philippe Goloub, Konstantina Oikonomou, Roland Sarda-Estève, Chrysanthos Savvides, Charbel Afif, Nikos Mihalopoulos, Stéphane Sauvage, and Jean Sciare
EGUsphere, https://doi.org/10.5194/egusphere-2022-1081, https://doi.org/10.5194/egusphere-2022-1081, 2022
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Our study presents, for the first time, a detailed source identification of aerosols at an urban background site in Cyprus (Eastern Mediterranean); a region strongly impacted by climate change and air pollution. Here we identify unexpected high contribution of long-range transported pollution from fossil fuel sources in the Middle East, highlighting an urgent need to further characterize these fast-growing emissions and their impacts on regional atmospheric composition, climate, and health.
Ren-Guo Zhu, Hua-Yun Xiao, Liqin Cheng, Huixiao Zhu, Hongwei Xiao, and Yunyun Gong
Atmos. Chem. Phys., 22, 14019–14036, https://doi.org/10.5194/acp-22-14019-2022, https://doi.org/10.5194/acp-22-14019-2022, 2022
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Sugars and amino acids are major classes of organic components in atmospheric fine particles and play important roles in the atmosphere. To identify their sources in different regions, the concentrations and compositions of sugar amino acids in fine particles were analysed. Our findings suggest that combining specific sugar tracers and chemical profiles of combined amino acids in local emission sources can identify various source characteristics of primary sources.
Hossein Dadashazar, Andrea F. Corral, Ewan Crosbie, Sanja Dmitrovic, Simon Kirschler, Kayla McCauley, Richard Moore, Claire Robinson, Joseph S. Schlosser, Michael Shook, K. Lee Thornhill, Christiane Voigt, Edward Winstead, Luke Ziemba, and Armin Sorooshian
Atmos. Chem. Phys., 22, 13897–13913, https://doi.org/10.5194/acp-22-13897-2022, https://doi.org/10.5194/acp-22-13897-2022, 2022
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Multi-season airborne data over the northwestern Atlantic show that organic mass fraction and the relative amount of oxygenated organics within that fraction are enhanced in droplet residual particles as compared to particles below and above cloud. In-cloud aqueous processing is shown to be a potential driver of this compositional shift in cloud. This implies that aerosol–cloud interactions in the region reduce aerosol hygroscopicity due to the jump in the organic : sulfate ratio in cloud.
Min Zhou, Guangjie Zheng, Hongli Wang, Liping Qiao, Shuhui Zhu, DanDan Huang, Jingyu An, Shengrong Lou, Shikang Tao, Qian Wang, Rusha Yan, Yingge Ma, Changhong Chen, Yafang Cheng, Hang Su, and Cheng Huang
Atmos. Chem. Phys., 22, 13833–13844, https://doi.org/10.5194/acp-22-13833-2022, https://doi.org/10.5194/acp-22-13833-2022, 2022
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The trend of aerosol pH and its drivers is crucial in understanding the multiphase formation pathways of aerosols. We reported the first trend analysis of aerosol pH from 2011 to 2019 in eastern China. Although significant variations of aerosol compositions were observed from 2011 to 2019, the aerosol pH estimated by model only slightly declined by 0.24. Our work shows that the opposite effects of SO42− and non-volatile cation changes play key roles in determining the moderate pH trend.
Zhenqi Xu, Wei Feng, Yicheng Wang, Haoran Ye, Yuhang Wang, Hong Liao, and Mingjie Xie
Atmos. Chem. Phys., 22, 13739–13752, https://doi.org/10.5194/acp-22-13739-2022, https://doi.org/10.5194/acp-22-13739-2022, 2022
Short summary
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This work uses a solvent (DMF) that can efficiently dissolve low-volatility OC to examine BrC absorption and sources, which will benefit future investigations on the physicochemical properties of large organic molecules. The study results also shed light on potential sources for methanol-insoluble OC. These results highlight the importance of testing different solvents to investigate the structures and light absorption of low-volatility BrC.
Sahil Bhandari, Zainab Arub, Gazala Habib, Joshua S. Apte, and Lea Hildebrandt Ruiz
Atmos. Chem. Phys., 22, 13631–13657, https://doi.org/10.5194/acp-22-13631-2022, https://doi.org/10.5194/acp-22-13631-2022, 2022
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Here we determine the sources of primary organic aerosol in Delhi, India, in two different seasons. In winter, the main sources are traffic and biomass burning; in the summer, the main sources are traffic and cooking. We obtain this result by conducting source apportionment resolved by time of day, using data from an aerosol chemical speciation monitor. Results from this work can be used to better design policies that target sources of organic aerosol.
Amy P. Sullivan, Rudra P. Pokhrel, Yingjie Shen, Shane M. Murphy, Darin W. Toohey, Teresa Campos, Jakob Lindaas, Emily V. Fischer, and Jeffrey L. Collett Jr.
Atmos. Chem. Phys., 22, 13389–13406, https://doi.org/10.5194/acp-22-13389-2022, https://doi.org/10.5194/acp-22-13389-2022, 2022
Short summary
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During the WE-CAN (Western Wildfire Experiment for Cloud Chemistry, Aerosol Absorption and Nitrogen) study, brown carbon (BrC) absorption was measured on the NSF/NCAR C-130 aircraft using a particle-into-liquid sampler and photoacoustic aerosol absorption spectrometer. Approximately 45 % of the BrC absorption in wildfires was observed to be due to water-soluble species. The ratio of BrC absorption to WSOC or ΔCO showed no clear dependence on fire dynamics or the time since emission over 9 h.
Ting-Yu Chen, Chia-Li Chen, Yi-Chi Chen, Charles C.-K. Chou, Haojia Ren, and Hui-Ming Hung
Atmos. Chem. Phys., 22, 13001–13012, https://doi.org/10.5194/acp-22-13001-2022, https://doi.org/10.5194/acp-22-13001-2022, 2022
Short summary
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The anthropogenic influence on aerosol composition in a downstream river-valley forest was investigated using FTIR and isotope analysis. A higher N-containing species concentration during daytime fog events indicates that a stronger inversion leads to higher pollutant concentrations, and the fog enhances the aqueous-phase chemical processes. Moreover, the observed size-dependent oxygen isotope suggests the contribution of organic peroxyl radicals to local nitrate formation for small particles.
Meng Wang, Yusen Duan, Wei Xu, Qiyuan Wang, Zhuozhi Zhang, Qi Yuan, Xinwei Li, Shuwen Han, Haijie Tong, Juntao Huo, Jia Chen, Shan Gao, Zhongbiao Wu, Long Cui, Yu Huang, Guangli Xiu, Junji Cao, Qingyan Fu, and Shun-cheng Lee
Atmos. Chem. Phys., 22, 12789–12802, https://doi.org/10.5194/acp-22-12789-2022, https://doi.org/10.5194/acp-22-12789-2022, 2022
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In this study, we report the long-term measurement of organic carbon (OC) and elementary carbon (EC) in PM2.5 with hourly time resolution conducted at a regional site in Shanghai from 2016 to 2020. The results from this study provide critical information about the long-term trend of carbonaceous aerosol, in particular secondary OC, in one of the largest megacities in the world and are helpful for developing pollution control measures from a long-term planning perspective.
Hazel Vernier, Neeraj Rastogi, Hongyu Liu, Amit Kumar Pandit, Kris Bedka, Anil Patel, Madineni Venkat Ratnam, Buduru Suneel Kumar, Bo Zhang, Harish Gadhavi, Frank Wienhold, Gwenael Berthet, and Jean-Paul Vernier
Atmos. Chem. Phys., 22, 12675–12694, https://doi.org/10.5194/acp-22-12675-2022, https://doi.org/10.5194/acp-22-12675-2022, 2022
Short summary
Short summary
The chemical composition of the stratospheric aerosols collected aboard high-altitude balloons above the summer Asian monsoon reveals the presence of nitrate/nitrite. Using numerical simulations and satellite observations, we found that pollution as well as lightning could explain some of our observations.
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Short summary
Ascorbic acid (AA) and Dithiothreitol (DTT) assay measures of water-soluble PM2.5 oxidative potential (OP) are compared in terms of spatiotemporal trends, chemical selectivity, sources, and health impacts based on an epidemiological study with backcast estimated OP. Both assays point to metals from brake/tire wear, but only the DTT assay also identifies organics from combustion. DTT is associated with emergency department visits for asthma/wheeze and congestive heart failure, whereas AA is not.
Ascorbic acid (AA) and Dithiothreitol (DTT) assay measures of water-soluble PM2.5 oxidative...
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