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The destruction of per- and polyfluoroalkyl substances (PFAS) is critical to ensure effective remediation of PFAS contaminated matrices. The destruction of hazardous chemicals within incinerators and other thermal treatment processes has historically been determined by calculatin...

Fires that occur in the wildland urban interface (WUI) often burn structures, vehicles, and their contents in addition to biomass in the natural landscape. Because these fires burn near population centers, their emissions may have a sizeable impact on public health, necessitating...

The declining trend in vehicle emissions has underscored the growing significance of Volatile Organic Compound (VOC) emissions from Volatile Chemical Products (VCP). However, accurately representing VOC chemistry in simplified chemical mechanisms remains challenging due to its ch...

Atmospheric nitrate is a key atmosphere component with implications for air quality, nutrient deposition, and climate.  However, accurately representing atmospheric nitrate concentrations within atmospheric chemistry models is a persistent challenge.  A contributing fac...

The US EPA has developed a set of annual North American anthropogenic and fire emissions data for criteria air pollutants across 18 broad source catagories for 2002 through 2017.  The sixteen new annual emissions inventories were developed using consistent input data and met...

Accurate fire emissions inventories are crucial to predict the impacts of wildland fires on air quality and atmospheric composition. Two traditional approaches are widely used to calculate fire emissions: a satellite-based top-down approach and a fuels-based bottom-up approach. H...

Formaldehyde (HCHO) is one of the most abundant non-methane volatile organic compounds (VOCs) emitted by fires. HCHO also undergoes chemical production and loss as a fire plume ages, and it can be an important oxidant precursor. In this study, we disentangle the process...

During the 2019 Fire Influence on Regional to Global Environments and Air Quality (FIREX-AQ) study, the NASA DC-8 carried out in situ chemical measurements in smoke plumes emitted from wildfires and agricultural fires in the contiguous United States. The DC-8 payload include...

Fires emit sufficient sulfur to affect local and regional air quality and climate. This study analyzes SO2 emission factors and variability in smoke plumes from US wildfires and agricultural fires, as well as their relationship to sulfate and hydroxymethanesulfonate (HMS) fo...

Globally, billions of people burn fuels indoors for cooking and heating, which contributes to millions of chronic illnesses and premature deaths annually. Additionally, residential burning contributes significantly to black carbon emissions, which have the highest global warming ...

Halogens (chlorine, bromine, and iodine) are known to profoundly influence atmospheric oxidants (hydroxyl radical (OH), hydroperoxyl radical (HO¿), ozone (O¿), and nitrate radical (NO¿)) in the troposphere and sub- sequently affecting air quality. H...

Aqueous film-forming foams (AFFFs) are used in firefighting applications, and often contain per- and polyfluoroalkyl substances (PFAS), which can detrimentally impact environmental and biological health. Incineration is a potential disposal method for AFFFs, which may produce sec...

As a Nature-Based Solution, roadside green infrastructure (also known as roadside barriers) can potentially mitigate traffic-related air pollution by increasing dispersion and promoting pollutant deposition. For new and existing barriers, the vegetation’s physical and ecolo...

This paper focuses on the impact of solid barriers located upwind of a highway in reducing vehicle related concentrations that occur downwind of the roadway, compared to a highway without barriers. Measurements made in the United States Environmental Protection Agency’s met...

Air pollution remains an important contributor to adverse health outcomes in the U.S. Currently, 121 million people, or one third of the U.S. population, live where National Ambient Air Quality Standards are violated.<span style='mso-element:field-begin'> ADDIN EN.CITE <...

Future estimates of atmospheric pollutant concentrations serve as critical information for policy makers to formulate current policy indicators to achieve future targets. Tropospheric burden of O3 is modulated not only by anthropogenic and natural precursor emissions, but also ...

Wildland fires, which includes both wild and prescribed fires, and agricultural fires in sum is one of the largest sources of fine particulate matter (PM2.5) emissions to the atmosphere in the United States. Although wildland fire PM2.5 emissions are primarily composed of carbona...

Computational fluid dynamics simulations are used to model the velocity field and the transport of a passive scalar within a micro-scale chamber used to measure diffusional transport through various building materials.  Comparisons of solutions obtained using a steady, lamin...

Mobile sources are responsible for a substantial controllable portion of the reactive organic carbon (ROC) emitted to the atmosphere, especially in urban environments of the United States. We update existing methods for calculating mobile source organic particle and vapor emissio...

Quantifying atmospheric loadings of total phosphorus (TP) to freshwater environments is essential to improve understanding of its fate and transport, and to mitigate the effects of excessive levels in freshwater ecosystems. To date, atmospheric deposition of TP in the U.S. is poo...

Air pollution has been associated with poor health outcomes and continues to be a risk factor for respiratory health in children. While higher particulate matter (PM) levels are associated with increased frequency of symptoms, lower lung function, and increase airway inflammation...

Emissions of SO2 resulting from volcanic degassing is one of the important sources that should be considered in the modeling system as it regulates tropospheric SO42- levels not only in the vicinity of the volcano but also through long-range transport that modulates background le...

Polylactic acid (PLA) filaments are widely used in fused filament fabrication (FFF) processes (3D printing). Filament additives such as metallic particles incorporated into PLA to modify functional and aesthetic features of print objects are becoming increasingly popular. However...

The scientific foundation for per- and polyfluoroalkyl substances (PFAS) measurements in water, soils, sediments, biosolids, biota, and outdoor air has rapidly expanded, however, there are limited efforts devoted to developing analytical methods to measure vapor-phase PFAS in ind...

The air quality of any given location is the result of complex interactions between meteorology and emissions through dynamical, physical, chemical, and photochemical processes. Of the many sources of air pollution, naturally produced emissions such as nitric oxide (NO) from soil...