Indoor Air Sources of Outdoor Air Pollution: Health Consequences, Policy, and Recommendations: An Official American Thoracic Society Workshop Report

Annals of the American Thoracic Society, Год журнала: 2024, Номер 21(3), С. 365 - 376

Опубликована: Март 1, 2024

Section:ChooseTop of pageAbstract <

Язык: Английский

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Linking gas, particulate, and toxic endpoints to air emissions in the Community Regional Atmospheric Chemistry Multiphase Mechanism (CRACMM)

Atmospheric chemistry and physics, Год журнала: 2023, Номер 23(9), С. 5043 - 5099

Опубликована: Май 4, 2023

Abstract. Chemical mechanisms describe the atmospheric transformations of organic and inorganic species connect air emissions to secondary such as ozone, fine particles, hazardous pollutants (HAPs) like formaldehyde. Recent advances in our understanding several chemical systems shifts drivers chemistry warrant updates used transport models Community Multiscale Air Quality (CMAQ) modeling system. This work builds on Regional Atmospheric Chemistry Mechanism version 2 (RACM2) develops Multiphase (CRACMM) 1.0, which demonstrates a fully coupled representation leading ozone aerosol (SOA) with consideration HAPs. CRACMMv1.0 includes 178 gas-phase species, 51 particulate 508 reactions spanning heterogeneous pathways. To support estimation health risks associated HAPs, nine CRACMM cover 50 % total cancer 60 non-cancer emission-weighted toxicity estimated for primary HAPs from anthropogenic biomass burning sources US, coverage higher (> 80 %) when formaldehyde acrolein are considered. In addition, new mechanism were added based importance their aerosol, or burden reactive carbon (ROC): sesquiterpenes, furans, propylene glycol, alkane-like low- intermediate-volatility compounds (9 species), oxygenated (16 aromatic hydrocarbons (2 slowly reacting carbon. Intermediate- lower-volatility increase ROC by 40 compared current operational mechanisms. Autoxidation, reaction particularly effective producing SOA, was C10 larger alkanes, hydrocarbons, monoterpene including second-generation aldehydes. Integrating radical SOA put additional constraints both enabled implementation previously unconsidered pathways phenolic furanone compounds, predicted account ∼ 30 hydrocarbon under typical conditions. found span atmospherically relevant range number, number oxygens per carbon, oxidation state slight high bias hydrogens total, 11 emitted implemented precursors CMAQv5.3.3 representations, resulting bottom-up prediction is required accurate source attribution design control strategies. available CMAQv5.4.

Язык: Английский

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Policy-Related Gains in Urban Air Quality May Be Offset by Increased Emissions in a Warming Climate

Environmental Science & Technology, Год журнала: 2023, Номер 57(26), С. 9683 - 9692

Опубликована: Июнь 16, 2023

Air quality policies have made substantial gains by reducing pollutant emissions from the transportation sector. In March 2020, New York City's activities were severely curtailed in response to COVID-19 pandemic, resulting 60–90% reductions human activity. We continuously measured major volatile organic compounds (VOCs) during January–April 2020 and 2021 Manhattan. Concentrations of many VOCs decreased significantly shutdown with variations daily patterns reflective activity perturbations, a temporary ∼28% reduction chemical reactivity. However, limited effect these dramatic measures was outweighed larger increases VOC-related reactivity anomalously warm spring 2021. This emphasizes diminishing returns transportation-focused alone risk increased temperature-dependent undermining policy-related warming climate.

Язык: Английский

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Comparing Urban Anthropogenic NMVOC Measurements With Representation in Emission Inventories—A Global Perspective

Journal of Geophysical Research Atmospheres, Год журнала: 2023, Номер 128(8)

Опубликована: Апрель 6, 2023

Abstract Emission inventories are a critical basis for air quality and climate modeling, as well policy decisions. Non‐methane volatile organic compounds (NMVOCs) key precursor in ozone secondary aerosol formation. Accurately representing NMVOCs emission is crucial understanding atmospheric chemistry, the impact of measures, projections. Improving NMVOC representation fraught with challenges, ranging from lack (long‐term) measurements, limited efforts updating factors, to diversity species reactivity. Here we take an initial step evaluate urban speciation inventory (EDGARv4.3.2 EDGARv6.1) at global level. To compare measurements estimates, ratios individual acetylene used. Owing limitations measurement data grouping inventories, comparison includes only number alkanes, alkenes, aromatics. Results show little no agreement between observations those compared ( r 2 0.01–0.20). This could be related incorrect profiles and/or spatial allocation areas. Regional better among 0.43–0.70). The inclusion oxygenated greater coverage improve mosaic regional may approach.

Язык: Английский

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Urban ozone formation and sensitivities to volatile chemical products, cooking emissions, and NO_x upwind of and within two Los Angeles Basin cities

Atmospheric chemistry and physics, Год журнала: 2025, Номер 25(2), С. 1121 - 1143

Опубликована: Янв. 28, 2025

Abstract. Volatile chemical products (VCPs) and other non-traditional anthropogenic sources, such as cooking, contribute substantially to the volatile organic compound (VOC) budget in urban areas, but their impact on ozone formation is less certain. This study employs Lagrangian box modeling sensitivity analyses evaluate response sector-specific VOC nitrogen oxide (NOx) emissions two Los Angeles (LA) Basin cities during summer of 2021. The model simulated photochemical processing transport temporally spatially gridded from FIVE-VCP-NEI17NRT inventory accurately simulates variability magnitude O3, NOx, speciated VOCs Pasadena, CA. show that (AVOC) enhance mean daily maximum 8 h average Pasadena by 13 ppb, whereas biogenic (BVOCs) 9.4 ppb. Of influenced AVOCs, VCPs represent largest fraction at 45 %, while cooking fossil fuel are comparable 26 % 29 respectively. NOx along trajectory paths indicate regime varies temporally. modeled primarily NOx-saturated across dense core peak production Pasadena. Lowering 25 moves NOx-limited chemistry afternoon hours shrinks spatial extent saturation towards downtown LA. Further using represented a separate state requires steeper reductions transition sensitivity, further suggesting representing reactivity inventories critical determining effectiveness future reduction policies.

Язык: Английский

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Two-year-long high-time-resolution apportionment of primary and secondary carbonaceous aerosols in the Los Angeles Basin using an advanced total carbon–black carbon (TC-BC(λ)) method

The Science of The Total Environment, Год журнала: 2022, Номер 848, С. 157606 - 157606

Опубликована: Июль 25, 2022

In recent years, carbonaceous aerosols (CA) have been recognized as a significant contributor to the concentration of particles smaller than 2.5 μm (i.e., PM2.5), with negative impact on public health and Earth's radiative balance. this study, we present method for CA apportionment based high-time-resolution measurements total carbon (TC), black (BC), spectral dependence absorption coefficient using recently developed Carbonaceous Aerosol Speciation System (CASS). Two-year-long at two different locations within California's Los Angeles Basin are presented. was apportioned its optical properties, organic or elemental composition, primary secondary origin. We found that (SOA), average, represent >50 % in study area, presumably resulting from oxidation anthropogenic biogenic volatile components. Remarkable peaks SOA summer afternoons were observed, fractional contribution up 90 %. On other hand, peak emitted CA, consisting BC aerosol (POA), contributed >80 during morning rush hours winter working days. The light dominated over brown (BrC), which 20 10 lower wavelength 370 nm nights afternoons, respectively. highest BrC, 50 %, observed wildfire periods. Although uncertainty levels can be high some components (such split between formed BrC nights), further research focused properties may help better constrain parameters used studies. believe CASS system combined presented offer simplified cost-effective insights into composition aerosols.

Язык: Английский

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Siloxane Emissions and Exposures during the Use of Hair Care Products in Buildings

Environmental Science & Technology, Год журнала: 2023, Номер 57(48), С. 19999 - 20009

Опубликована: Ноя. 16, 2023

Cyclic volatile methyl siloxanes (cVMS) are ubiquitous in hair care products (HCPs). cVMS emissions from HCPs of concern, given the potential adverse impact on environment and human health. To characterize exposures during use HCPs, realistic experiments were conducted a residential building. Siloxane-based tested using common styling techniques, including straightening, curling, waving, oiling. VOC concentrations measured via proton-transfer-reaction time-of-flight mass spectrometry. HCP drove rapid changes chemical composition indoor atmosphere. dominated use, decamethylcyclopentasiloxane (D5) contributed most to emissions. emission factors (EFs) routines ranged 110-1500 mg/person influenced by type, tools, operation temperatures, length. The high temperature tools surface area enhanced Increasing straightener room 210 °C increased EFs 50-310%. Elevated can result substantial indoor-to-outdoor transport ventilation (0.4-6 tons D5/year U.S.); thus, may augment abundance outdoor

Язык: Английский

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Secondary Organic Aerosol Formation from Volatile Chemical Product Emissions: Model Parameters and Contributions to Anthropogenic Aerosol

Environmental Science & Technology, Год журнала: 2023, Номер 57(32), С. 11891 - 11902

Опубликована: Авг. 1, 2023

Volatile chemical products (VCP) are an increasingly important source of hydrocarbon and oxygenated volatile organic compound (OVOC) emissions to the atmosphere, these likely play role as anthropogenic precursors for secondary aerosol (SOA). While SOA from VCP hydrocarbons is often accounted in models, formation, evolution, properties OVOCs remain uncertain. We use environmental chamber data a kinetic model develop parameters 10 representing glycols, glycol ethers, esters, aromatics, amines. Model simulations suggest that mass yields same magnitude widely studied (e.g., long-chain alkanes, monoterpenes, single-ring aromatics), exhibit linear correlation with carbon number precursor. When combined inventories two megacities United States (US) US-wide inventory, we find VOCs react OH form 0.8–2.5× much SOA, by mass, mobile sources. Hydrocarbons (terpenes, branched cyclic alkanes) (terpenoids, ethers) make up 60–75 25–40% arising use, respectively. This work contributes growing body knowledge focused on studying VOC contributions urban air pollution.

Язык: Английский

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O₃ Sensitivity to NO_x and VOC During RECAP-CA: Implication for Emissions Control Strategies

ACS ES&T Air, Год журнала: 2024, Номер 1(6), С. 536 - 546

Опубликована: Апрель 15, 2024

Lack of recent progress in reducing ground-level ozone (O3) concentrations to comply with health-based standards the South Coast Air Basin (SoCAB) has motivated a reanalysis emission control strategies. Here we used two parallel transportable smog chamber systems measure sensitivity O3 volatile organic compounds (VOCs) and nitrogen oxides (NOx = NO + NO2) Pasadena Redlands, California from July October, 2021. The system measures ambient chemical regime by comparing formation basecase perturbed chamber. monthly median observed was stable VOC-limited regime, but showed seasonal trend where October transitioned towards NOx-limited August September. Day-specific at both Redlands could be either or on O3-nonattainment days. Calculated isopleths for were constructed using photochemical box model based comprehensive measurements NOx VOCs during Re-Evaluating Chemistry Pollutants (RECAP-CA) campaign. good agreement measurements. calculations suggest that an additional ∼40% reduction is needed move 95% days above 70 ppb further reductions will result lower concentrations.

Язык: Английский

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Emission characteristics of reactive organic gases (ROGs) from industrial volatile chemical products (VCPs) in the Pearl River Delta (PRD), China

Atmospheric chemistry and physics, Год журнала: 2024, Номер 24(12), С. 7101 - 7121

Опубликована: Июнь 20, 2024

Abstract. Volatile chemical products (VCPs) have become an important source of reactive organic gases (ROGs) in urban areas worldwide. Industrial activities can also utilize a large number VCPs and emit many into the atmosphere. Due to multiple sampling measurement challenges, only subset ROG species is usually measured for industrial VCP sources. This study aims investigate emissions ROGs from five sources Pearl River Delta (PRD) region China, including shoemaking, plastic surface coating, furniture printing, ship coating industries. A more comprehensive speciation these was developed by combination proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS) gas chromatography–mass spectrometer/flame ionization detector (GC–MS/FID). Our identified oxygenated (OVOCs) as representative emitted sources, which are highly related specific chemicals used during activities. Moreover, spectra similarity analysis revealed significant dissimilarities among activities, indicating substantial variations between different Except industry utilizing solvent-borne coatings, proportions OVOCs range 67 % 96 total 72 97 OH reactivity (OHR) while corresponding contributions 16 ± 3.5 15 3.6 %. The associated with coatings exhibited higher ozone formation potential (OFP), reaching high 5.5 2.7 g O3 g−1 industries, primarily due aromatics. We find that few contribute majority their OHR OFP various results suggest treatment devices may limited effectiveness all ROGs, efficiencies ranging −12 68 Furthermore, we found ambient measurements been significantly impacted pairs (e.g., methyl ethyl ketone (MEK) / C8 aromatics ratio) be utilized reliable evidence using high-time-resolution PTR-ToF-MS. demonstrated importance measuring PTR-ToF-MS characterizing

Язык: Английский

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