E-Cigarettes: A Hazy Hazard

• Electronic cigarettes (e-cigarettes or e-cigs) are battery-powered devices that deliver vaporized nicotine and other substances, such as flavorings, to users without smoke or combustion. They are commonly marketed as smoking cessation tools and, as such, are promoted as being a healthier alternative to smoking. • A common misperception is that that e-cigarettes only release water vapor. In reality, though, these devices release nicotine and other chemicals in a vapor form that can expose both the user (a.k.a., the vaper), as well as those in the immediate vicinity, to those contaminants. While the health risks of e-cigarettes compared to regular cigarette smoking is greatly reduced, many toxic compounds are still present. • The rapid increase in use of electronic cigarettes has generated a potential concern for indoor air quality in that there is still limited data on potential exposures and human health risks for users, or for others through second- and third-hand exposures

The Value of IAQ: A Review of the Scientific Evidence Supporting the Benefits of Investing in Better Indoor Air Quality

Other studies have examined how ventilation rates, combined with the presence of pollutant sources, can affect productivity. These studies provide evidence that increased ventilation, including increases above common guidance levels such as ASHRAE’s ventilation standards, improve occupant productivity. Increased occupant control over ventilation has also been shown to improve productivity. Higher indoor carbon dioxide (CO2) levels have been directly associated with impaired work performance and increased health symptoms. Historically, it was believed that these associations exist only because higher indoor CO2 concentrations, resulting from lower outdoor air ventilation rates, are also correlated with higher levels of other indoor-generated pollutants that directly cause the adverse effects. More recent studies, however, have found that CO2 itself, even at levels previously considered acceptable, may have adverse effects. Considering the benefits and demonstrated return on investment, building owners and operators should consider proactive methods of improving IAQ. Established strategies and guidelines are readily available to help identify and implement IAQ-related improvements. These include recognizing and addressing potential and real IAQ issues during the design, construction, renovation, and ongoing maintenance of buildings. Research has found that the benefits of IAQ improvement far outweigh the costs, with estimates of 3–6 times returns for increased ventilation, 8 times returns for increased filtration, and up to 60 times returns when all improvements and related benefits are combined. Collectively, the scientific literature demonstrates that improved workplace productivity and reduced absenteeism from improved IAQ have been shown to provide substantial financial benefits, with the benefits often greatly outweighing the associated costs

Rapid evolution of aerosol particles and their optical properties downwind of wildfires in the western US

During the first phase of the Biomass Burn Operational Project (BBOP) field campaign, conducted in the Pacific Northwest, the DOE G-1 aircraft was used to follow the time evolution of wildfire smoke from near the point of emission to locations 2-3.5 h downwind. In nine flights we made repeated transects of wildfire plumes at varying downwind distances and could thereby follow the plume\u27s time evolution. On average there was little change in dilution-normalized aerosol mass concentration as a function of downwind distance. This consistency hides a dynamic system in which primary aerosol particles are evaporating and secondary ones condensing. Organic aerosol is oxidized as a result. On all transects more than 90 % of aerosol is organic. In freshly emitted smoke aerosol, NH+4 is approximately equivalent to NO3. After 2 h of daytime aging, NH+4 increased and is approximately equivalent to the sum of Cl, SO24, and NO3. Particle size increased with downwind distance, causing particles to be more efficient scatters. Averaged over nine flights, mass scattering efficiency (MSE) increased in ∼ 2 h by 56 % and doubled in one flight. Mechanisms for redistributing mass from small to large particles are discussed. Coagulation is effective at moving aerosol from the Aitken to accumulation modes but yields only a minor increase in MSE. As absorption remained nearly constant with age, the time evolution of single scatter albedo was controlled by age-dependent scattering. Near-fire aerosol had a single scatter albedo (SSA) of 0.8-0.9. After 1 to 2 h of aging SSAs were typically 0.9 and greater. Assuming global-average surface and atmospheric conditions, the observed age dependence in SSA would change the direct radiative effect of a wildfire plume from near zero near the fire to a cooling effect downwind

Influence of urban pollution on the production of organic particulate matter from isoprene epoxydiols in central Amazonia

The atmospheric chemistry of isoprene contributes to the production of a substantial mass fraction of the particulate matter (PM) over tropical forests. Isoprene epoxydiols (IEPOX) produced in the gas phase by the oxidation of isoprene under HO2-dominant conditions are subsequently taken up by particles, thereby leading to production of secondary organic PM. The present study investigates possible perturbations to this pathway by urban pollution. The measurement site in central Amazonia was located 4 to 6 h downwind of Manaus, Brazil. Measurements took place from February through March 2014 of the wet season, as part of the GoAmazon2014/5 experiment. Mass spectra of organic PM collected with an Aerodyne Aerosol Mass Spectrometer were analyzed by positive-matrix factorization. One resolved statistical factor (IEPOX-SOA factor) was associated with PM production by the IEPOX pathway. The IEPOX-SOA factor loadings correlated with independently measured mass concentrations of tracers of IEPOX-derived PM, namely C5-alkene triols and 2-methyltetrols (R = 0. 96 and 0.78, respectively). The factor loading, as well as the ratio f of the loading to organic PM mass concentration, decreased under polluted compared to background conditions. For an increase in NOy concentration from 0.5 to 2 ppb, the factor loading and f decreased by two to three fold. Overall, sulfate concentration explained 37 % of the variability in the factor loading. After segregation of factor loading into subsets based on NOy concentration, the sulfate concentration explained up to 75 % of the variability. Considering both factors, the data sets show that the suppressing effects of increased NO concentrations dominated over the enhancing effects of higher sulfate concentrations. The pollution from Manaus elevated NOy concentrations more significantly than sulfate concentrations relative to background conditions. In this light, increased emissions of nitrogen oxides, as anticipated for some scenarios of Amazonian economic development, could significantly alter pathways of PM production that presently prevail over the tropical forest, implying changes to air quality and regional climate.</html

Chronicles of Oklahoma

Article narrates the experiences of John L. Springston, an 83-year-old Cherokee man, as he lived in within Spavinaw, a town in Oklahoma, throughout his lifetime. His story details the history of the town and its hidden secrets

E-Cigarettes: A Hazy Hazard

• Electronic cigarettes (e-cigarettes or e-cigs) are battery-powered devices that deliver vaporized nicotine and other substances, such as flavorings, to users without smoke or combustion. They are commonly marketed as smoking cessation tools and, as such, are promoted as being a healthier alternative to smoking. • A common misperception is that that e-cigarettes only release water vapor. In reality, though, these devices release nicotine and other chemicals in a vapor form that can expose both the user (a.k.a., the vaper), as well as those in the immediate vicinity, to those contaminants. While the health risks of e-cigarettes compared to regular cigarette smoking is greatly reduced, many toxic compounds are still present. • The rapid increase in use of electronic cigarettes has generated a potential concern for indoor air quality in that there is still limited data on potential exposures and human health risks for users, or for others through second- and third-hand exposures

The Value of IAQ: A Review of the Scientific Evidence Supporting the Benefits of Investing in Better Indoor Air Quality

Other studies have examined how ventilation rates, combined with the presence of pollutant sources, can affect productivity. These studies provide evidence that increased ventilation, including increases above common guidance levels such as ASHRAE’s ventilation standards, improve occupant productivity. Increased occupant control over ventilation has also been shown to improve productivity. Higher indoor carbon dioxide (CO2) levels have been directly associated with impaired work performance and increased health symptoms. Historically, it was believed that these associations exist only because higher indoor CO2 concentrations, resulting from lower outdoor air ventilation rates, are also correlated with higher levels of other indoor-generated pollutants that directly cause the adverse effects. More recent studies, however, have found that CO2 itself, even at levels previously considered acceptable, may have adverse effects. Considering the benefits and demonstrated return on investment, building owners and operators should consider proactive methods of improving IAQ. Established strategies and guidelines are readily available to help identify and implement IAQ-related improvements. These include recognizing and addressing potential and real IAQ issues during the design, construction, renovation, and ongoing maintenance of buildings. Research has found that the benefits of IAQ improvement far outweigh the costs, with estimates of 3–6 times returns for increased ventilation, 8 times returns for increased filtration, and up to 60 times returns when all improvements and related benefits are combined. Collectively, the scientific literature demonstrates that improved workplace productivity and reduced absenteeism from improved IAQ have been shown to provide substantial financial benefits, with the benefits often greatly outweighing the associated costs

Overview of the Cumulus Humilis aerosol processing study

The Cumulis Humilis Aerosol Processing Study (CHAPS) campaign was designed to collect observations relevant to a number of issues related to aerosols and clouds, including differences in below-cloud aerosol optical and cloud nucleating properties downwind of Oklahoma City, the distribution of aerosol extinction in the vicinity of shallow clouds and differences in aerosol extinction in the vicinity of shallow clouds. CHAPS utilized a sampling strategy closely linking the DOE G-1, the National Aeronautics and Space Administration (NASA) B200 aircraft and primary and secondary surface sites. Observations of boundary layer aerosols and meteorological conditions were made at the primary surface site just north of Oklahoma City and sky cover was measured at a nearby secondary surface site. The sampling streams from both the inlets fed into essentially identical instrument systems for measuring the particles optical properties. The observed data is useful for in-depth analysis, including model studies related to the activation of aerosols as they are lifted up from the convective boundary layer into the clouds

Comparison of aircraft measurements during GoAmazon2014/5 and ACRIDICON-CHUVA

The indirect effect of atmospheric aerosol particles on the Earth's radiation balance remains one of the most uncertain components affecting climate change throughout the industrial period. The large uncertainty is partly due to the incomplete understanding of aerosol–cloud interactions. One objective of the GoAmazon2014/5 and the ACRIDICON (Aerosol, Cloud, Precipitation, and Radiation Interactions and Dynamics of Convective Cloud Systems)-CHUVA (Cloud Processes of the Main Precipitation Systems in Brazil) projects was to understand the influence of emissions from the tropical megacity of Manaus (Brazil) on the surrounding atmospheric environment of the rainforest and to investigate its role in the life cycle of convective clouds. During one of the intensive observation periods (IOPs) in the dry season from 1 September to 10 October 2014, comprehensive measurements of trace gases and aerosol properties were carried out at several ground sites. In a coordinated way, the advanced suites of sophisticated in situ instruments were deployed aboard both the US Department of Energy Gulfstream-1 (G1) aircraft and the German High Altitude and Long-Range Research Aircraft (HALO) during three coordinated flights on 9 and 21 September and 1 October. Here, we report on the comparison of measurements collected by the two aircraft during these three flights. Such comparisons are challenging but essential for assessing the data quality from the individual platforms and quantifying their uncertainty sources. Similar instruments mounted on the G1 and HALO collected vertical profile measurements of aerosol particle number concentrations and size distribution, cloud condensation nuclei concentrations, ozone and carbon monoxide mixing ratios, cloud droplet size distributions, and downward solar irradiance. We find that the above measurements from the two aircraft agreed within the measurement uncertainties. The relative fraction of the aerosol chemical composition measured by instruments on HALO agreed with the corresponding G1 data, although the total mass loadings only have a good agreement at high altitudes. Furthermore, possible causes of the discrepancies between measurements on the G1 and HALO are examined in this paper. Based on these results, criteria for meaningful aircraft measurement comparisons are discussed