A critical review of perfluoroalkyl and polyfluoroalkyl substances (PFAS) landfill disposal in the United States.

Landfills manage materials containing per- and polyfluoroalkyl substances (PFAS) from municipal solid waste (MSW) and other waste streams. This manuscript summarizes state and federal initiatives and critically reviews peer-reviewed literature to define best practices for managing these wastes and identify data gaps to guide future research. The objective is to inform stakeholders about waste-derived PFAS disposed of in landfills, PFAS emissions, and the potential for related environmental impacts.

Variability in the inorganic composition of colored acrylonitrile-butadiene-styrene and polylactic acid filaments used in 3D printing.

Fused filament fabrication is a 3D printing technique that has gained widespread use from homes to schools to workplaces. Thermoplastic filaments, such as acrylonitrile-butadiene-styrene (ABS) and polylactic acid (PLA), are extruded at temperatures near their respective glass transition temperature or melting point, respectively. Little has been reported on the inorganic elemental composition and concentrations present in these materials or the methods available for extracting that information.

Toxicity of fresh and aged anthropogenic smoke particles emitted from different burning conditions.

There is substantial evidence that photochemical reactions in the atmosphere cause physico-chemical transformation of combustion smoke, but how this processing modifies potential health effects in exposed populations is not well understood. Here we utilized a new approach to simulate photochemical aging of anthropogenic smoke emissions (a mixture of plastic, plywood, and cardboard smoke) from two different burning conditions (smoldering vs. flaming) and investigated their adverse outcomes associated with mutagenic activity and the relative potencies of different polycyclic aromatic hydrocarbons (PAHs).

Characterization of PFAS air emissions from thermal application of fluoropolymer dispersions on fabrics.

During thermal processes utilized in affixing fluoropolymer coatings dispersion to fibers and fabrics, coating components are vaporized. It is suspected that per- and polyfluoroalkyl substances (PFAS) from the dispersions may undergo chemical transformations at the temperatures used, leading to additional emitted PFAS thermal byproducts. It is important to characterize these emissions to support evaluation of the resulting environmental and health impacts.

Contributions of particulate and gas phases of simulated burn pit smoke exposures to impairment of respiratory function.

Objective: Inhalation of smoke from the burning of waste materials on military bases is associated with increased incidences of cardiopulmonary diseases. This study examined the respiratory and inflammatory effects of acute inhalation exposures in mice to smoke generated by military burn pit-related materials including plywood (PW), cardboard (CB), mixed plastics (PL), and a mixture of these three materials (MX) under smoldering (0.84 MCE) and flaming (0.

Chemistry and lung toxicity of particulate matter emitted from firearms.

Smoke emissions produced by firearms contain hazardous chemicals, but little is known if their properties change depending on firearm and ammunition type and whether such changes affect toxicity outcomes. Pulmonary toxicity was assessed in mice exposed by oropharyngeal aspiration to six different types of smoke-related particulate matter (PM) samples; (1) handgun PM, (2) rifle PM, (3) copper (Cu) particles (a surrogate for Cu in the rifle PM) with and without the Cu chelator penicillamine, (4) water-soluble components of the rifle PM, (5) soluble components with removal of metal ions, and (6) insoluble components of the rifle PM. Gun firing smoke PM was in the respirable size range but the chemical composition varied with high levels of Pb in the handgun and Cu in the rifle smoke.

NO retrievals from NOAA-20 OMPS: Algorithm, evaluation, and observations of drastic changes during COVID-19.

We present the first NO measurements from the Nadir Mapper of Ozone Mapping and Profiler Suite (OMPS) instrument aboard the NOAA-20 satellite. NOAA-20 OMPS was launched in November 2017, with a nadir resolution of 17 × 13 km similar to the Ozone Monitoring Instrument (OMI). The retrieval of NOAA-20 NO vertical columns were achieved through the Direct Vertical Column Fitting (DVCF) algorithm, which was uniquely designed and successfully used to retrieve NO from OMPS aboard Suomi National Polar-orbiting Partnership (SNPP) spacecraft, predecessor to NOAA-20.

Temporal trends in methane emissions from a small eutrophic reservoir: the key role of a spring burst.

Waters impounded behind dams (i.e., reservoirs) are important sources of greenhouses gases (GHGs), especially methane (CH), but emission estimates are not well constrained due to high spatial and temporal variability, limitations in monitoring methods to characterize hot spot and hot moment emissions, and the limited number of studies that investigate diurnal, seasonal, and interannual patterns in emissions.

Chemistry, lung toxicity and mutagenicity of burn pit smoke-related particulate matter.

Background: Open burning of anthropogenic sources can release hazardous emissions and has been associated with increased prevalence of cardiopulmonary health outcomes. Exposure to smoke emitted from burn pits in military bases has been linked with respiratory illness among military and civilian personnel returning from war zones. Although the composition of the materials being burned is well studied, the resulting chemistry and potential toxicity of the emissions are not.

Establishing the Suitability of the Model for Prediction Across Scales for Global Retrospective Air Quality Modeling.

The U.S. EPA is leveraging recent advances in meteorological modeling to construct an air quality modeling system to allow consistency from global to local scales.

Large-scale comparison of E. coli levels determined by culture and a qPCR method (EPA Draft Method C) in Michigan towards the implementation of rapid, multi-site beach testing.

Fecal pollution remains a challenge for water quality managers at Great Lakes and inland recreational beaches. The fecal indicator of choice at these beaches is typically Escherichia coli (E. coli), determined by culture-based methods that require over 18 h to obtain results.

Impact of scale-aware deep convection on the cloud liquid and ice water paths and precipitation using the Model for Prediction Across Scales (MPAS-v5.2).

The cloud liquid water path (LWP), ice water path (IWP), and precipitation simulated with uniform- and variable-resolution numerical experiments using the Model for Prediction Across Scales (MPAS) are compared against Clouds and the Earth's Radiant Energy System (CERES) and Tropical Rainfall Measuring Mission data. Our comparison between monthly-mean model diagnostics and satellite data focuses on the convective activity regions of the tropical Pacific Ocean, extending from the Tropical Eastern Pacific Basin where trade wind boundary layer clouds develop to the Western Pacific Warm Pool characterized by deep convective updrafts capped with extended upper-tropospheric ice clouds. Using the scale-aware Grell-Freitas (GF) and Multiscale Kain-Fritsch (MSKF) convection schemes in conjunction with the Thompson cloud microphysics, uniform-resolution experiments produce large biases between simulated and satellite-retrieved LWP, IWP, and precipitation.

Studying Scale Dependency of Aerosol Cloud Interactions using Multi-Scale Cloud Formulations.

The WRF-ACI model configuration is used to investigate the scale dependency of aerosol-cloud interactions (ACI) across the "grey zone" scales for grid and subgrid-scale clouds. The impacts of ACI on weather are examined across regions in the eastern and western U. S.

A short history of methods used to measure bathing beach water quality.

The enumeration of fecal indicators of bathing beach water to determine quality have been used since the mid-20th century. In the 1930s and as late the 1970s, the Most Probable Number procedure for estimating microbial densities in water was in general use. The most probable number procedure was replaced as a method of choice by the membrane filter procedure.