Emission and Evolution of Submicron Organic Aerosol in Smoke from Wildfires in the Western United States

ACS Earth and Space Chemistry, Journal Year: 2019, Volume and Issue: 3(7), P. 1237 - 1247

Published: June 12, 2019

Despite increasing incidence of wildfires in the United States, wildfire smoke is poorly characterized, with little known about particle composition and emission rates. Chemistry transported plumes confounds interpretation ground aircraft data, but near-field observations can potentially disentangle effects oxidation dilution on aerosol mass chemical composition. We report organic (OA) ratios from near fire source for 20 sampled during Western Wildfire Experiment: Cloud Chemistry, Aerosol Absorption, Nitrogen (WE-CAN) study summer 2018. observe no changes submicron nonrefractory OA concentration, relative to CO which accounts simple dilution, between 0.5 up 8 h aging. However, static excess mixing hide shifts that suggest near-balanced, simultaneous oxidation-driven condensation dilution-driven evaporation. Specifically, we significant increases extent oxidation, evident by an increase marker f44 loss biomass burning f60, as ages through chemistry dilution. discuss competing oxidative evaporation evolution aerosols over time.

Language: Английский

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Secondary organic aerosol association with cardiorespiratory disease mortality in the United States

Nature Communications, Journal Year: 2021, Volume and Issue: 12(1)

Published: Dec. 16, 2021

Abstract Fine particle pollution, PM 2.5 , is associated with increased risk of death from cardiorespiratory diseases. A multidecadal shift in the United States (U.S.) composition towards organic aerosol as well advances predictive algorithms for secondary (SOA) allows novel examinations role components on mortality. Here we show SOA strongly county-level rates U.S. independent total mass association largest associations located southeastern Compared to variability across 3.5× greater per capita On a basis, 6.5× higher rate mortality than and biogenic anthropogenic carbon sources both play overall Our results suggest reducing health impacts requires consideration SOA.

Language: Английский

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Radical chemistry in oxidation flow reactors for atmospheric chemistry research

Chemical Society Reviews, Journal Year: 2020, Volume and Issue: 49(9), P. 2570 - 2616

Published: Jan. 1, 2020

We summarize the studies on chemistry in oxidation flow reactor and discuss its atmospheric relevance.

Language: Английский

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Air quality changes in cities during the COVID-19 lockdown: A critical review

Atmospheric Research, Journal Year: 2021, Volume and Issue: 264, P. 105823 - 105823

Published: Aug. 25, 2021

Language: Английский

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Organic Peroxides in Aerosol: Key Reactive Intermediates for Multiphase Processes in the Atmosphere

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(4), P. 1635 - 1679

Published: Jan. 11, 2023

Organic peroxides (POs) are organic molecules with one or more peroxide (−O–O−) functional groups. POs commonly regarded as chemically labile termination products from gas-phase radical chemistry and therefore serve temporary reservoirs for oxidative radicals (HOx ROx) in the atmosphere. Owing to their ubiquity, active gas-particle partitioning behavior, reactivity, key reactive intermediates atmospheric multiphase processes determining life cycle (formation, growth, aging), climate, health impacts of aerosol. However, there remain substantial gaps origin, molecular diversity, fate due complex nature dynamic behavior. Here, we summarize current understanding on POs, a focus identification quantification, state-of-the-art analytical developments, molecular-level formation mechanisms, chemical transformation pathways, well environmental impacts. We find that interactions SO2 transition metal ions generally fast PO pathways liquid water, lifetimes estimated be minutes hours, while hydrolysis is particularly important α-substituted hydroperoxides. Meanwhile, photolysis thermolysis likely minor sinks POs. These distinctly different fates, such reaction OH radicals, which highlights need understand By summarizing advances remaining challenges investigation propose future research priorities regarding fate,

Language: Английский

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Effect of Atmospheric Aging on Soot Particle Toxicity in Lung Cell Models at the Air–Liquid Interface: Differential Toxicological Impacts of Biogenic and Anthropogenic Secondary Organic Aerosols (SOAs)

Environmental Health Perspectives, Journal Year: 2022, Volume and Issue: 130(2)

Published: Feb. 1, 2022

Background: Secondary organic aerosols (SOAs) formed from anthropogenic or biogenic gaseous precursors in the atmosphere substantially contribute to ambient fine particulate matter [PM ≤2.5μm aerodynamic diameter (PM2.5)] burden, which has been associated with adverse human health effects. However, there is only limited evidence on their differential toxicological impact. Objectives: We aimed discriminate effects of generated by atmospheric aging combustion soot particles (SPs) (β-pinene) (naphthalene) two different lung cell models exposed at air–liquid interface (ALI). Methods: Mono- cocultures epithelial cells (A549) and endothelial (EA.hy926) were ALI for 4 h aerosol concentrations a photochemically aged mixture primary SP β-pinene (SOAβPIN-SP) naphthalene (SOANAP-SP). The internally mixed soot/SOA comprehensively characterized terms physical chemical properties. conducted toxicity tests determine cytotoxicity, intracellular oxidative stress, secondary genotoxicity, as well inflammatory angiogenic Results: observed considerable toxicity-related outcomes treated either SOA type. Greater measured SOANAP-SP compared SOAβPIN-SP both models, whereas nano-sized cores alone showed minor At functional level, we found that augmented secretion malondialdehyde interleukin-8 may have induced activation coculture system. This was confirmed comet assay, suggesting genotoxicity greater potential. Chemical characterization PM revealed distinct qualitative differences composition types. Discussion: In this study using A549 EA.hy926 ALI, compounds had than SPs. Photochemical formation more oxidized, aromatic SOAs higher potential β-pinene. Thus, conclude influence chemistry plays crucial role outcome emissions. https://doi.org/10.1289/EHP9413

Language: Английский

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Reactive Oxygen Species Formed by Secondary Organic Aerosols in Water and Surrogate Lung Fluid

Environmental Science & Technology, Journal Year: 2018, Volume and Issue: unknown

Published: Sept. 20, 2018

Reactive oxygen species (ROS) play a central role in adverse health effects of air pollutants. Respiratory deposition fine particulate matter can lead to the formation ROS epithelial lining fluid, potentially causing oxidative stress and inflammation. Secondary organic aerosols (SOA) account for large fraction matter, but their is unclear. Here, we quantify compare yields potential isoprene, β-pinene, naphthalene SOA water surrogate lung fluid (SLF). In pure water, isoprene β-pinene were found produce mainly OH radicals, whereas produced H2O2 O2•-. The total molar 11.8% 8.2% decreased 8.5% 5.2% SLF, which be attributed removal by antioxidants. A positive correlation between peroxide concentration yield suggests that (hydro)peroxides may an important from biogenic SOA. was 1.7% increased 11.3% SLF. This strong increase likely due redox reaction cycles involving environmentally persistent free radicals (EPFR) or semiquinones, antioxidants, oxygen, promote anthropogenic aromatic precursors.

Language: Английский

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Effects of Atmospheric Processing on the Oxidative Potential of Biomass Burning Organic Aerosols

Environmental Science & Technology, Journal Year: 2019, Volume and Issue: 53(12), P. 6747 - 6756

Published: May 15, 2019

Oxidative potential (OP), which is the ability of certain components in atmospheric particles to generate reactive oxidative species (ROS) and deplete antioxidants vivo, a prevailing toxicological mechanism underlying adverse health effects associated with exposure ambient aerosols. While previous studies have identified high OP fresh biomass burning organic aerosols (BBOA), it remains unclear how evolves throughout transport. Using dithiothreitol (DTT) assay as measure OP, combination field observations laboratory experiments used determine aging transforms intrinsic (OPmassDTT) BBOA. For BBOA collected during fire seasons Greece, OPmassDTT was observed increase by factor 2.1 ± 0.9 for samples ages up 68 h. Laboratory indicate that aqueous photochemical (aging UVB UVA photolysis; well OH oxidation), ozone dilution can transform water-soluble fraction wood smoke within 2 days The results from this work suggest air quality impacts emissions extend beyond regions near sites should be accounted for.

Language: Английский

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Role of pH in Aerosol Processes and Measurement Challenges

The Journal of Physical Chemistry A, Journal Year: 2018, Volume and Issue: 123(7), P. 1275 - 1284

Published: Dec. 26, 2018

pH is one of the most basic chemical properties aqueous solution, but its measurement in nanoscale aerosol particles presents many challenges. The growing interest atmospheric chemistry community because demonstrated effects on heterogeneous and human health, as well potential climate. authors have shown that phase transitions are sensitive to pH, focusing systems undergo liquid-liquid separation. Currently, calculated indirectly from knowledge species present gas phases through use thermodynamic models. From these models, ambient expected be highly acidic (pH ∼ 0-3). Direct measurements focused model due difficulty this measurement. This area which physical chemists should encouraged contribute consequences for processes environment.

Language: Английский

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Particulate Matter Toxicity Is Nrf2 and Mitochondria Dependent: The Roles of Metals and Polycyclic Aromatic Hydrocarbons

Chemical Research in Toxicology, Journal Year: 2020, Volume and Issue: 33(5), P. 1110 - 1120

Published: April 17, 2020

Particulate matter (PM), an important component of air pollution, induces significant adverse health effects. Many the observed effects caused by inhaled PM are associated with oxidative stress and inflammation. This association has been linked in particular to particles' chemical components, especially inorganic/metal organic/polycyclic aromatic hydrocarbon (PAH) fractions, their ability generate reactive oxygen species biological systems. The transcription factor NF-E2 nuclear erythroid-related 2 (Nrf2) is activated redox imbalance regulates expression phase II detoxifying enzymes. Nrf2 plays a key role preventing PM-induced toxicity protecting against damage review focuses on specific particularly dissolved metals PAH roles inducing inflammation cell animal models respect mitochondria.

Language: Английский

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