Key Toxicity Enhancement Effect of Aqueous-Phase Secondary Formation: Insights from Hourly Measurements during Haze Events

Journal of Hazardous Materials, Год журнала: 2025, Номер unknown, С. 138139 - 138139

Опубликована: Апрель 1, 2025

Язык: Английский

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Emission dynamics of reactive oxygen species and oxidative potential in particles from a petrol car and wood stove

Aerosol Research, Год журнала: 2025, Номер 3(1), С. 205 - 218

Опубликована: Апрель 22, 2025

Abstract. Air pollution is one of the largest environmental health risks and leading causes adverse outcomes mortality worldwide. The possible importance oxidative potential (OP) as a metric to quantify particle toxicity in air increasingly being recognised. In this work, OP reactive oxygen species (ROS) activity particles from fresh aged petrol passenger car emissions residential wood combustion (RWC) were investigated using two novel instruments. Applying online instruments an ascorbic acid (AA) 2′,7′-dichlorodihydrofluorescein (DCFH) assay provides much higher temporal resolution compared with traditional filter-based methods allows for new insights into highly dynamic changes ROS these sources. Due efficiency particulate filter Euro 6d car, almost no primary emitted and, thus, or was detected exhaust. However, substantial ROSs observed after photochemical ageing due formation secondary particles. Increasing also when comparing RWC emissions. Overall, had signals This suggests that could be major contributor may intrinsically more harmful emission source than exhaust, although still high. These measurements illustrate strong differences nature toxicity-relevant properties sources contribute efficient mitigation policies.

Язык: Английский

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Transported smoke from crop residue burning as the major source of organic aerosol and health risks in northern Indian cities during post-monsoon

Environment International, Год журнала: 2025, Номер unknown, С. 109583 - 109583

Опубликована: Июнь 1, 2025

Язык: Английский

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Opinion: How will advances in aerosol science inform our understanding of the health impacts of outdoor particulate pollution?

Atmospheric chemistry and physics, Год журнала: 2024, Номер 24(20), С. 11981 - 12011

Опубликована: Окт. 28, 2024

Abstract. Air pollution, characterized by high levels of particulate matter (PM), poses the greatest environmental threat to human health, causing an estimated 7 million deaths annually and accounting for 5 % global gross domestic product (GDP). While health impacts PM are influenced toxicity its individual chemical constituents, mortality burden is solely based on total mass concentration. This because a lack large-scale, high-resolution data composition, needed epidemiological assessments. Identifying which constituents harmful has been “holy grail” atmospheric science since landmark 1993 study six US cities established definitive link between mortality. Ever since, scientists have focused understanding aerosol emission sources, formation pathways, while longitudinal studies required individual-level exposure data, employing land use regression models prediction exposures at fine resolutions. In this opinion article, we argue that time come shift focus towards incorporating composition into assessments, laying foundation development new regulatory metrics. will enable creation targeted guidelines subsequent regulations, prioritizing mitigation efforts against most anthropogenic emissions. Central availability global, long-term, obtained through field observations modelling outputs. underscore key milestones within integral advancing foundational shift. Specifically, examine emerging tools estimating components, present type ambient model developments, identify gaps in our fundamental emissions their transformation, propose cross-disciplinary collaboration epidemiologists understand components. We contend now reached pivotal moment elucidating differential representing first step incorporation air quality guidelines.

Язык: Английский

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Comprehensive Analysis of Emissions from Wood and Cow Dung Burning Using Chemometrics and Two-Dimensional Gas Chromatography

Опубликована: Янв. 1, 2024

Biomass burning is a global source of climate- and health-affecting gasses, aerosol, particulate matter. The impacts biomass emissions (BBE) are believed to be partially tied their complex variable chemical makeup. For instance, the nitrogen content BBE influences capacity absorb light, therefore affect Earth's radiative budget. Factors such as temperature, type, or air flow rate during combustion all modify composition BBE. these reasons, accurate characterization challenging, which parameters most appreciably change not fully understood. Therefore, technique capable both unbiased individual compounds well identification potential sample groups would highly beneficial towards deconvoluting emissions. Herein, for first time, principal component analysis (PCA) was applied gathered on filters laboratory-based wood two types cow dung in tube furnace. A thermal desorption dimensional time-of-flight gas chromatography mass spectrometry (TD-GC×GC-ToF-MS) setup employed separate identify species. By combining techniques with feature selection algorithm, we determined whether obtained under various conditions could reliably differentiated, changes unsaturation, content, emission tracers levoglucosan were observable result. Through PCA, that low temperature responsible major differences after combustion. Additionally, observed had higher factor nitrogen-containing species also present emissions, potentially leading underestimation its impacts. Overall, TD-GC×GC-ToF-MS coupled PCA separated from biomass, displaying suitability this combination characterization.

Язык: Английский

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Biomass burning organic aerosol (BBOA) from wildfires has multiple phases and is more viscous than laboratory generated BBOA

Опубликована: Май 7, 2024

Biomass burning organic aerosol (BBOA) is a major contributor to in the atmosphere. The impacts of BBOA on climate and health depend strongly their physicochemical properties, including viscosity phase behaviour (number types phases); these relationships chemistry, are not yet fully characterized. We collected field samples during 2021 British Columbia wildfire season constrain at range relative humidities, compared them laboratory generated made from smoldering pine wood. Particles all exhibited two-phased with higher polarity hydrophilic core lower hydrophobic shell. used poke-flow technique estimate particles. found that both phases had viscosities >10 8 Pa s humidities up 50%, which more viscous than any or proxies previously measured. Aerosol mass spectrometry showed were oxidized those lab, likely explanation for viscosity. two high have implications how should be treated atmospheric models

Язык: Английский

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Comprehensive Analysis of Emissions from Wood and Cow Dung Burning using Chemometrics and Two-Dimensional Gas Chromatography

Chemosphere, Год журнала: 2024, Номер unknown, С. 143445 - 143445

Опубликована: Окт. 1, 2024

Язык: Английский

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Molecular characterization of major oxidative potential active species in ambient PM2.5: Emissions from biomass burning and ship exhaust

Environmental Pollution, Год журнала: 2024, Номер 363, С. 125291 - 125291

Опубликована: Ноя. 13, 2024

Язык: Английский

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High Viscosity and Two Phases Observed over a Range of Relative Humidities in Biomass Burning Organic Aerosol from Canadian Wildfires

Environmental Science & Technology, Год журнала: 2024, Номер unknown

Опубликована: Ноя. 28, 2024

Biomass burning organic aerosol (BBOA) is a major contributor to in the atmosphere. The impacts of BBOA on climate and health depend strongly upon their physicochemical properties, including viscosity phase behavior (number types phases); these properties are not yet fully characterized. We collected field samples during 2021 British Columbia wildfire season constrain at range relative humidities compared them previous studies BBOA. Particles from all exhibited two-phased with polar hydrophilic nonpolar hydrophobic phase. used poke-flow technique estimate particles. Both phases had viscosities >108 Pa s up 50%. Such high correspond mixing times within 200 nm particles >5 h. Two have implications for how should be treated atmospheric models.

Язык: Английский

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Impacts of Aging and Relative Humidity on Properties of Biomass Burning Smoke Particles

ACS ES&T Air, Год журнала: 2024, Номер 2(1), С. 109 - 118

Опубликована: Дек. 6, 2024

Quantifying changes in the properties of smoke aerosols under varying conditions is important for understanding health and environmental impacts exposure to smoke. Smoke composition, aerosol liquid water content, effective density (ρeff), other can change significantly as travels through areas different ambient over time. During this study, we measured composition physical due oxidative aging humidity. We found that led SOA formation increases ratios organic carbon elemental carbon. Aerosol content increased with increasing relative humidity (RH), aged took up more than fresh at all levels, likely a combination surface polarity low medium RH area high RH. Growth factors ranged from 1.06 ± 0.08 1.32 Oxidative ρeff. For 100 nm particles, ρeff ∼1.2 ∼1.6 Results these experiments suggest leads restructuring compaction and/or chemistry.

Язык: Английский

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