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Atmospheric Environment

Jessica G Charrier, Alexander S McFall, Kennedy K-T Vu, James Baroi, Catalina Olea, Alam Hasson, Cort Anastasio
The dithiothreitol (DTT) assay is widely used to measure the oxidative potential of particulate matter. Results are typically presented in mass-normalized units (e.g., pmols DTT lost per minute per microgram PM) to allow for comparison among samples. Use of this unit assumes that the mass-normalized DTT response is constant and independent of the mass concentration of PM added to the DTT assay. However, based on previous work that identified non-linear DTT responses for copper and manganese, this basic assumption (that the mass-normalized DTT response is independent of the concentration of PM added to the assay) should not be true for samples where Cu and Mn contribute significantly to the DTT signal...
November 2016: Atmospheric Environment
Allison P Patton, Robert Laumbach, Pamela Ohman-Strickland, Kathy Black, Shahnaz Alimokhtari, Paul Lioy, Howard M Kipen
Commuting in automobiles can contribute substantially to total traffic-related air pollution (TRAP) exposure, yet measuring commuting exposures for studies of health outcomes remains challenging. To estimate real-world TRAP exposures, we developed and evaluated the robustness of a scripted drive protocol on the NJ Turnpike and local roads between April 2007 and October 2014. Study participants were driven in a car with closed windows and open vents during morning rush hours on 190 days. Real-time measurements of PM2...
October 2016: Atmospheric Environment
Erin A Riley, Timothy Gould, Kris Hartin, Scott A Fruin, Christopher D Simpson, Michael G Yost, Timothy Larson
Ultrafine particle number (UFPN) and size distributions, black carbon, and nitrogen dioxide concentrations were measured downwind of two of the busiest airports in the world, Los Angeles International Airport (LAX) and Hartsfield-Jackson International Airport (ATL - Atlanta, GA) using a mobile monitoring platform. Transects were located between 5 km and 10 km from the ATL and LAX airports. In addition, measurements were taken at 43 additional urban neighborhood locations in each city and on freeways. We found a 3-5 fold increase in UFPN concentrations in transects under the landing approach path to both airports relative to surrounding urban areas with similar ground traffic characteristics...
August 2016: Atmospheric Environment
Jason E Ham, Joel C Harrison, Stephen R Jackson, J R Wells
The reaction products from limonene ozonolysis were investigated using the new carbonyl derivatization agent, O-tert-butylhydroxylamine hydrochloride (TBOX). With ozone (O3) as the limiting reagent, five carbonyl compounds were detected. The yields of the carbonyl compounds are discussed with and without the presence of a hydroxyl radical (OH•) scavenger, giving insight into the influence secondary OH radicals have on limonene ozonolysis products. The observed reaction product yields for limonaketone (LimaKet), 7-hydroxyl-6-oxo-3-(prop-1-en-2-yl)heptanal (7H6O), and 2-acetyl-5-oxohexanal (2A5O) were unchanged suggesting OH• generated by the limonene + O3 reaction does not contribute to their formation...
May 2016: Atmospheric Environment
Erin A Riley, LaNae Schaal, Miyoko Sasakura, Robert Crampton, Timothy R Gould, Kris Hartin, Lianne Sheppard, Timothy Larson, Christopher D Simpson, Michael G Yost
Mobile monitoring has provided a means for broad spatial measurements of air pollutants that are otherwise impractical to measure with multiple fixed site sampling strategies. However, the larger the mobile monitoring route the less temporally dense measurements become, which may limit the usefulness of short-term mobile monitoring for applications that require long-term averages. To investigate the stationarity of short-term mobile monitoring measurements, we calculated long term medians derived from a mobile monitoring campaign that also employed 2-week integrated passive sampler detectors (PSD) for NOx, Ozone, and nine volatile organic compounds at 43 intersections distributed across the entire city of Baltimore, MD...
May 2016: Atmospheric Environment
Marie-Cecile G Chalbot, Priyanka Chitranshi, Gonçalo Gamboa da Costa, Erik Pollock, Ilias G Kavouras
The functional and (13)C isotopic compositions of water-soluble organic carbon (WSOC) in atmospheric aerosol were determined by nuclear magnetic resonance ((1)H-NMR) and isotope ratio mass spectrometry (IRMS) in an urban location in the Southern Mississippi Valley. The origin of WSOC was resolved using the functional distribution of organic hydrogen, δ(13)C ratio, and positive matrix factorization (PMF). Three factors were retained based on NMR spectral bins loadings. Two factors (factors 1 and 3) demonstrated strong associations with the aliphatic region in the NMR spectra and levoglucosan resonances...
March 2016: Atmospheric Environment
Meng Wang, Joshua P Keller, Sara D Adar, Sun-Young Kim, Timothy V Larson, Casey Olives, Paul D Sampson, Lianne Sheppard, Adam A Szpiro, Sverre Vedal, Joel D Kaufman
BACKGROUND: Current epidemiologic studies rely on simple ozone metrics which may not appropriately capture population ozone exposure. For understanding health effects of long-term ozone exposure in population studies, it is advantageous for exposure estimation to incorporate the complex spatiotemporal pattern of ozone concentrations at fine scales. OBJECTIVE: To develop a geo-statistical exposure prediction model that predicts fine scale spatiotemporal variations of ambient ozone in six United States metropolitan regions...
December 2015: Atmospheric Environment
Anita Shepherd, Xiaoyuan Yan, Dali Nayak, Jamie Newbold, Dominic Moran, Mewa Singh Dhanoa, Keith Goulding, Pete Smith, Laura M Cardenas
China accounts for a third of global nitrogen fertilizer consumption. Under an International Panel on Climate Change (IPCC) Tier 2 assessment, emission factors (EFs) are developed for the major crop types using country-specific data. IPCC advises a separate calculation for the direct nitrous oxide (N2O) emissions of rice cultivation from that of cropland and the consideration of the water regime used for irrigation. In this paper we combine these requirements in two independent analyses, using different data quality acceptance thresholds, to determine the influential parameters on emissions with which to disaggregate and create N2O EFs...
December 2015: Atmospheric Environment
J-S Youn, E Crosbie, L C Maudlin, Z Wang, A Sorooshian
Aerosol and cloud water measurements of dimethylamine (DMA), the most abundant amine in this study, were conducted in semi-arid (Tucson, Arizona) and marine (Nucleation in California Experiment, NiCE; central coast of California) areas. In both regions, DMA exhibits a unimodal aerosol mass size distribution with a dominant peak between 0.18 and 0.56 μm. Particulate DMA concentrations increase as a function of marine biogenic emissions, sulfate, BVOC emissions, and aerosol-phase water. Such data supports biogenic sources of DMA, aminium salt formation, and partitioning of DMA to condensed phases...
December 2015: Atmospheric Environment
Andres Martinez, Scott N Spak, Nicholas T Petrich, Dingfei Hu, Gregory R Carmichael, Keri C Hornbuckle
Indiana Harbor and Ship Canal (IHSC) in East Chicago is an industrial waterway on Lake Michigan and a source of PCBs to Lake Michigan and the overlying air. We hypothesized that IHSC is an important source of airborne PCBs to surrounding communities. We used AERMOD to model hourly PCB concentrations, utilizing emission fluxes from a prior study and hourly meteorology provided by the State of Indiana. We also assessed dispersion using hourly observed meteorology from a local airport and high resolution profiles simulated by the Weather Research and Forecasting model...
December 1, 2015: Atmospheric Environment
Laurel E Plummer, Christopher M Carosino, Keith J Bein, Yongjing Zhao, Neil Willits, Suzette Smiley-Jewell, Anthony S Wexler, Kent E Pinkerton
The EPA regulates ambient particulate matter (PM) because substantial associations have been established between PM and health impacts. Presently, regulatory compliance involves broad control of PM emission sources based on mass concentration rather than chemical composition, although PM toxicity is likely to vary depending upon PM physicochemical properties. The overall objective of this study was to help inform source-specific PM emission control regulations. For the first time, source-oriented PM was collected from the atmosphere in Fresno, CA, onto 38 source/size substrates...
October 1, 2015: Atmospheric Environment
Sara Elizabeth Grineski, Juana M Herrera, Priyangi Bulathsinhala, Joan G Staniswalis
STUDY OBJECTIVE: Linkages between pollution and morbidity have been observed in numerous studies. But race/ethnicity has been underemphasized as a modifier of that association, and few studies have tested for a Hispanic Health Paradox in sensitivity to air pollution. METHODS: Daily asthma, chronic obstructive pulmonary disease (COPD) and congestive heart failure (CHF) hospital admissions in El Paso, Texas were studied in age groups and insurance groups. Daily PM2...
October 1, 2015: Atmospheric Environment
Francesca Pannullo, Duncan Lee, Eugene Waclawski, Alastair H Leyland
It has been well documented that air pollution adversely affects health, and epidemiological pollution-health studies utilise pollution data from automatic monitors. However, these automatic monitors are small in number and hence spatially sparse, which does not allow an accurate representation of the spatial variation in pollution concentrations required for these epidemiological health studies. Nitrogen dioxide (NO2) diffusion tubes are also used to measure concentrations, and due to their lower cost compared to automatic monitors are much more prevalent...
October 2015: Atmospheric Environment
Nicole S Ngo, Michael Gatari, Beizhan Yan, Steven N Chillrud, Kheira Bouhamam, Patrick L Kinneym
Few studies examine urban air pollution in sub-Saharan Africa (SSA), yet urbanization rates there are among the highest in the world. In this study, we measured 8-hr average occupational exposure levels of fine particulate matter (PM2.5), black carbon (BC), ultra violet active-particulate matter (UV-PM), and trace elements for individuals who worked along roadways in Nairobi, specifically bus drivers, garage workers, street vendors, and women who worked inside informal settlements. We found BC and re-suspended dust were important contributors to PM2...
June 2015: Atmospheric Environment
Brent Altemose, Jicheng Gong, Tong Zhu, Min Hu, Liwen Zhang, Hong Cheng, Lin Zhang, Jian Tong, Howard M Kipen, Pamela Ohman Strickland, Qingyu Meng, Mark G Robson, Junfeng Zhang
This study was carried out to characterize three aldehydes of health concern (formaldehyde, acetaldehyde, and acrolein) at a central Beijing site in the summer and early fall of 2008 (from June to October). Aldehydes in polluted atmospheres come from both primary and secondary sources, which limits the control strategies for these reactive compounds. Measurements were made before, during, and after the Beijing Olympics to examine whether the dramatic air pollution control measures implemented during the Olympics had an impact on concentrations of the three aldehydes and their underlying primary and secondary sources...
May 1, 2015: Atmospheric Environment
Michael S Waring, J Raymond Wells
Indoor chemistry may be initiated by reactions of ozone (O3), the hydroxyl radical (OH), or the nitrate radical (NO3) with volatile organic compounds (VOC). The principal indoor source of O3 is air exchange, while OH and NO3 formation are considered as primarily from O3 reactions with alkenes and nitrogen dioxide (NO2), respectively. Herein, we used time-averaged models for residences to predict O3, OH, and NO3 concentrations and their impacts on conversion of typical residential VOC profiles, within a Monte Carlo framework that varied inputs probabilistically...
April 2015: Atmospheric Environment
Stuart Batterman, Richard Cook, Thomas Justin
Traffic activity encompasses the number, mix, speed and acceleration of vehicles on roadways. The temporal pattern and variation of traffic activity reflects vehicle use, congestion and safety issues, and it represents a major influence on emissions and concentrations of traffic-related air pollutants. Accurate characterization of vehicle flows is critical in analyzing and modeling urban and local-scale pollutants, especially in near-road environments and traffic corridors. This study describes methods to improve the characterization of temporal variation of traffic activity...
April 2015: Atmospheric Environment
Jared Downard, Ashish Singh, Robert Bullard, Thilina Jayarathne, Chathurika Rathnayake, Donald L Simmons, Brian R Wels, Scott N Spak, Thomas Peters, Douglas Beardsley, Charles Stanier, Elizabeth A Stone
In summer 2012, a landfill liner comprising an estimated 1.3 million shredded tires burned in Iowa City, Iowa. During the fire, continuous monitoring and laboratory measurements were used to characterize the gaseous and particulate emissions and to provide new insights into the qualitative nature of the smoke and the quantity of pollutants emitted. Significant enrichments in ambient concentrations of CO, CO2, SO2, particle number (PN), fine particulate (PM2.5) mass, elemental carbon (EC), and polycyclic aromatic hydrocarbons (PAH) were observed...
March 1, 2015: Atmospheric Environment
Ashish Singh, Scott N Spak, Elizabeth A Stone, Jared Downard, Robert Bullard, Mark Pooley, Pamela A Kostle, Matthew W Mainprize, Michael D Wichman, Thomas Peters, Douglas Beardsley, Charles O Stanier
The Iowa City Landfill in eastern Iowa, United States, experienced a fire lasting 18 days in 2012, in which a drainage layer of over 1 million shredded tires burned, generating smoke that impacted the surrounding metropolitan area of 130,000 people. This emergency required air monitoring, risk assessment, dispersion modeling, and public notification. This paper quantifies the impact of the fire on local air quality and proposes a monitoring approach and an Air Quality Index (AQI) for use in future tire fires and other urban fires...
March 2015: Atmospheric Environment
Jaime E Mirowsky, Lan Jin, George Thurston, David Lighthall, Tim Tyner, Lori Horton, Karen Galdanes, Steven Chillrud, James Ross, Kent E Pinkerton, Lung Chi Chen, Morton Lippmann, Terry Gordon
Particulate matter (PM) varies in chemical composition and mass concentration based on location, source, and particle size. This study sought to evaluate the in vitro and in vivo toxicity of coarse (PM10-2.5) and fine (PM25) PM samples collected at 5 diverse sites within California. Coarse and fine PM samples were collected simultaneously at 2 rural and 3 urban sites within California during the summer. A human pulmonary microvascular endothelial cell line (HPMEC-ST1.6R) was exposed to PM suspensions (50 μg/mL) and analyzed for reactive oxygen species (ROS) after 5 hours of treatment...
February 2015: Atmospheric Environment
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