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Chan, Wing-man Polly. "Aspects of air quality management for particulate matter /". View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37120803.
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Chan, Wing-man Polly, i 陳詠文. "Aspects of air quality management for particulate matter". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B45013354.
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Hammonds, Mark David. "Characterisation of carbonaceous particulate matter in Edinburgh". Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/6236.
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Airborne particulate matter (PM) has important harmful effects on human health, as well as a number of other important atmospheric effects. Although progress has been made in understanding the sources and effects of PM, there remains considerable uncertainty on a number of issues, including the nature of a lot of the carbonaceous material, which comprises 30{50% on average of PM mass. This project aims to compare different methods of PM measurement, and contribute understanding to the nature and origin of the carbonaceous fraction of PM. Daily samples of PM10 were collected from three sites in the Edinburgh area using Partisol-Plus 2025 Sequential Air Samplers: 1) Urban Background (20 August 2008 until 21 April 2010); 2) Rural (25 February 2009 until 21 April 2009); and 3) Roadside (10 September 2009 until 21 April 2010). These localities provided PM that was, respectively, representative of: 1) city-wide background air; 2) air at a location distanced from population centres, roads and industrial areas; and 3) air influenced by the emissions associated with traffic. Gravimetric PM10 concentration (µgm-3) was determined for each daily filter sample, after a blank correction to compensate for the relative humidity (RH)-influenced change in filter mass over time. The correction was successful, with good agreement attained between the Partisol and a PM10 Tapered Element Oscillating Microbalance Filter Dynamics Measurement System (TEOM-FDMS) co-located at the Urban Background site. The general levels of PM10 measured in this monitoring campaign indicate that the air in Edinburgh was relatively clean. The main factor causing exceedance of the daily European Union (EU) limit value was shown to be transport of PM10 from areas of mainland Europe. High PM10 concentrations were also strongly associated with calm weather conditions in Edinburgh, which allowed the build-up of particulate pollution over time. Aethalometer-equivalent daily concentrations of black carbon (BC) were determined by measuring the optical reflectance of the PM10 filters from the Partisol samplers. The conversion of reflectance values to BC concentrations relied on a number of correction factors, which may have impacted on the accuracy of the results with time and location. The concentration of BC in Edinburgh was shown to be relatively low, with the daily variation being controlled by local emissions and meteorology. BC as a proportion of PM10 increased with sampling location in the order: Rural < Urban Background < Roadside. Predominantly traffic-related BC concentrations increased during periods of low wind speed and were not greatly influenced by long-range transport of aerosol. Daily water-soluble organic matter (WSOM) concentrations were obtained by aqueous extraction of the filter samples and measurement of the dissolved organic carbon (DOC). About 11% on average of the Edinburgh PM10 was WSOM. The majority of this WSOM seemed to have originated from air masses outside of the city, although there was a minor contribution from urban traffic sources. A solid phase extraction (SPE) procedure was used to isolate about one-third of the WSOM as hydrophobic compounds and this revealed a relative increase in the amount of less oxygenated material from traffic sources. Higher than average WSOM concentrations were strongly associated with calm weather conditions that allowed the transient build-up of particle concentrations. Some of the peaks in WSOM concentration were related to the transport of air masses from areas of mainland Europe where biogenic secondary organic aerosol (SOA) and biomass burning were likely sources. Analysis of the WSOM samples by UV-Vis absorption spectroscopy showed clear seasonal trends in the composition of hydrophobic watersoluble organic matter (HWSOM), interpreted as predominance of lower molecular weight aliphatic compounds in summer but predominance of larger aromatic and polyconjugated compounds in winter. Raman spectra were obtained for different carbonaceous reference materials. The results of curve fitting for these spectra gave D1 band full width at half maximum (FWHM) values that distinguished between diesel exhaust particles from a local bus and a humic acid sample. Analysis of Edinburgh PM10 samples using Raman microspectroscopy (RM) showed a variation in the structural order of the carbon compounds present between that of soot and HUmic-LIke Substances (HULIS), with a tendency towards more soot-like material being present. There was no strong relationship between carbonaceous order and BC concentration, showing that coloured organic compounds have the potential to influence reflectance measurements. The combination of these measurement approaches has yielded insights into the nature and variation in carbonaceous PM material with time and sampling location.
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Boswell, Colin R. "Atlanta automotive particulate matter exposure and evaluation". Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34679.
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The following thesis titled, Atlanta Automotive Particulate Matter Exposure and Evaluation, presents data obtained as a part of a joint project with Emory University, Rollin's School of Public Health. The Atlanta Commuters Exposure (ACE) Study uses both real-time and time-integrated sampling techniques for ambient aerosol concentrations. The ACE study is unique in that it will correlate the ambient aerosol concentrations with the concurrent health measurements. The primary objective of this thesis is to measure the concentration, size distribution and the chemical composition of PM2.5 inside the vehicle cabin for several commuters. The vehicles followed a scripted route along roadways in the Atlanta metropolitan region during periods of peak traffic volume, while the compact air sampling package of both real-time and time-integrated instruments recorded data. Real-time measurements for Particulate Matter (PM) were made using compact Optical Particle Counters (OPC), a Condensation Particle Counter, and a MicroAethalometer. The time-integrated measurements for Elemental Carbon (EC), Organic Carbon (OC), Water Soluble Organic Carbon (WSOC), particulate elemental concentrations, and speciated organics required filter collection methods. Thus a compact air-sampling package was created to combine both sets of real-time and time-integrated instruments. The following results are presented for the first four commutes. The framework for analyzing and presenting results is developed, and will be used for future commutes.
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Napelenok, Sergey L. "Sensitivity Analysis in Air Quality Models for Particulate Matter". Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/14083.
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Fine particulate matter (PM2.5) has been associated with a variety of problems that include adverse health effects, reduction in visibility, damage to buildings and crops, and possible interactions with climate. Although stringent air quality regulations are in place, policy makers need efficient tools to test a wide range of control strategies. Sensitivity analysis provides predictions on how the interdependent concentrations of various PM2.5 components and also gaseous pollutant species will respond to specific combinations of precursor emission reductions. The Community Multiscale Air Quality Model (CMAQ) was outfitted with the Decoupled Direct Method in 3D for calculating sensitivities of particulate matter (DDM-3D/PM). This method was evaluated and applied to high PM2.5 episodes in the Southeast United States. Sensitivities of directly emitted particles as well as those formed in the atmosphere through chemical and physical processing of emissions of gaseous precursors such as SO2, NOx, VOCs, and NH3 were calculated. DDM-3D/PM was further extended to calculate receptor oriented sensitivities or the Area of Influence (AOI). AOI analysis determines the geographical extent of relative air pollutant precursor contributions to pollutant levels at a specific receptor of interest. This method was applied to Atlanta and other major cities in Georgia. The tools developed here (DDM-3D/PM and AOI) provide valuable information to those charged with air quality management.
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Chan, Sik-foon Joyce. "Application of cluster analysis to identify sources of particulate matter in Hong Kong /". Hong Kong : University of Hong Kong, 1995. http://sunzi.lib.hku.hk/hkuto/record.jsp?B1470920X.
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Micallef, Alfred. "Concentrations and vertical profiles of airborne particulate matter". Thesis, University of Nottingham, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285453.
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Pritchard, Joseph James. "The effects of secondary air injection on particulate matter emissions". Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/87963.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2014.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 69-71).
An experimental study was performed to investigate the effects of secondary air injection (SAI) on particulate matter (PM) emissions. SAI was developed to reduce hydrocarbon (HC) emissions and has been shown to be effective as a strategy to reduce HC emissions at cold-start. In general, cold-start emissions have become an increasingly important problem due to new, more stringent vehicle emissions regulations. Direct-injection, spark-ignition (DISI) engines, which emit high levels of PM, are growing in popularity because of their fuel efficiency improvements. Meeting PM emissions becomes a more difficult task due to more stringent standards and the greater adoption of DISI engines. This study seeks to investigate the potential use of SAI to reduce PM emissions in the exhaust system. Engine based experiments were conducted using a 2.0 L, turbocharged, DISI General Motors LNF engine. The engine was outfitted with a secondary air injection system and several thermocouples to measure exhaust stream temperature. A TSI Model 3934 Scanning Mobility Particle Sizer (SMPS) was used to measure particle emissions at various engine operating conditions and secondary air rates. PM reductions were observed for the engine conditions and SAI flow rates that were tested. The maximum particle number reduction achieved was 80%. Particle number and particle volume reduction were observed to correlate well with exhaust enthalpy release.
by Joseph James Pritchard.
S.M.
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Diaz, Poueriet Pablo. "Analysis of Sources Affecting Ambient Particulate Matter in Brownsville, Texas". Thesis, University of North Texas, 2012. https://digital.library.unt.edu/ark:/67531/metadc115069/.
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Texas is the second largest state in U.S.A. based on geographical area, population and the economy. It is home to several large coastal urban areas with major industries and infrastructure supporting the fossil-fuel based energy sector. Most of the major cities on the state have been impacted by significant air pollution events over the past decade. Studies conducted in the southern coastal region of TX have identified long range transport as a major contributor of particulate matter (PM) pollution along with local emissions. Biomass burns, secondary sulfates and diesel emissions sources are comprise as the dominant mass of PM2.5 have been noted to be formed by the long range transport biomass from Central America. Thus, the primary objective of this study was to identify and quantify local as well as regional sources contributing to the PM pollution in the coastal area of Brownsville located along the Gulf of Mexico. Source apportionment techniques such as principal component analysis (PCA) and positive matrix factorization (PMF) were employed on the air quality monitoring data to identify and quantify local and regional sources affecting this coastal region. As a supplement to the PMF and PCA, conditional probability function (CPF) analysis and potential source contribution function (PSCF) analysis were employed to characterize the meteorological influences for PM events. PCA identified an optimal solution of 6 sources affecting the coastal area of Brownsville, while PMF resolved 8 sources for the same area. Biomass comingled with sea salt was identified to be the dominant contributor from the PCA analysis with 30.2% of the apportioned PM mass in Brownsville, meanwhile PMF account secondary sulfates I & II with 27.6%. the other common sources identified included, biomass burning, crustal dust, secondary sulfate, oil combustion, mobile sources and miscellaneous traffic sources.
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Backes, Audrey Ann. "Evaluation of Particulate Matter Inside Control Rooms at a Quarry and Processing Facility". University of Toledo Health Science Campus / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=mco1418321178.
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Appelhans, Tim. "A climatology of particulate pollution in Christchurch". Thesis, University of Canterbury. Geography, 2010. http://hdl.handle.net/10092/4014.
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The research presented in this thesis provides a quantitative analysis of atmospheric influences on particulate matter pollution in Christchurch across a wide range of spatial and temporal scales. A complex interaction of low level flow characteristics that form in response to local and regional features of complex terrain, together with an urban setting that is characterised by low density housing, mostly comprised of single storey dwellings that are poorly insulated, regularly leads to nocturnal smog events during winter in Christchurch. Provided synoptic flow is weak, the above mentioned flow interaction promotes flow stagnation over the city, when nocturnal katabatic drainage flows and day-time north-easterly on-shore winds converge over the city. Additionally, undercutting of the density currents promotes highly stable atmospheric stratification close to the surface, so that, in combination, both horizontal and vertical air movement is suppressed. As particulate emission release from solid fuel burning for home heating coincides with this poor atmospheric dispersion potential, particle concentrations can increase substantially so that national air quality guidelines are regularly exceeded during winter in Christchurch.
At the core of this thesis is a classification based approach that examines the day-to-day probabilities of breaches of the national air quality guideline for PM over the last decade at a single location in Christchurch as a result of variations in meteorological conditions alone. It is shown that, based on variations in temperature and wind speed, up to 85% of exceedence occurrence can be explained. From this, concentration trends over time, when meteorological variability is kept to a minimum, are assessed and evidence is found that recent regulatory measures to enhance air quality are beginning to show positive effects. Atmospheric processes that control pollution dispersion on the mesoscale are investigated through means of atmospheric numerical modelling in a novel approach that assimilates observational climatic wind field averages to drive low level flow for two idealised case studies. It is shown that this approach is able to reproduce the observed diurnal concentration patterns very well and that much of these patterns can be attributed to mesoscale circulation characteristics and associated atmospheric dispersion potential, namely flow stagnation and recirculation of contaminants. When timing of stagnation and subsequent recirculation is such that it occurs within a few hours after peak emission release, concentration increase is enhanced and dilution is delayed, thus severely exacerbating the problem. Links between exceedence probabilities and synoptic situations that favour the degradation of air quality are established and various synoptic transition scenarios are examined with regard to local air quality. The progression of anticyclones across the country is identified to be the dominant synoptic control mechanism and it is shown that latitudinal variation in the progression path determines the extent of expected exceedence probability. On interdecadal hemispheric scales, it is found that a particular combination of local and synoptic atmospheric conditions that favours air quality degradation, shows a re-occurring pattern of frequency maxima (and minima) with a periodicity of approximately 14 - 16 years. For the synoptic part of this interdecadal variability, a close relationship to Southern Hemispheric pressure anomalies in high latitudes is revealed. Finally, for verification of the combined findings and to assess their prediction capability, a validation case study is given which shows that the applied methodology is able to capture day-to-day variations in pollution levels with acceptable (statistically significant) accuracy.
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Jilla, Abhinay Mr. "Particulate Matter and Carbon Monoxide Emission Factors from Incense Burning". ScholarWorks@UNO, 2017. http://scholarworks.uno.edu/td/2380.
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Indoor air quality is a growing concern in the world. People spend a considerable amount of time in indoor environments such as homes, workplaces, shopping malls, stores, and so on. Indoor sources like incense and candle burning, cooking contribute a significant amount of indoor air pollutants such as particulate matter, carbon monoxide (CO), volatile organic compounds. Exposure to these kinds of pollutants can result in adverse health effects.
The purpose of this research is to determine the particulate matter and carbon monoxide emission factors (EFs) from incense stick burning. A test chamber with a rectangular exhaust duct, a fan to exhaust air with pollutants in it, and pollutant sensors were used to achieve the project goals. Several experiments were performed with different cases/scenarios to accurately estimate the EFs and several test runs were conducted for each case to test the repeatability of the results.
The CO, PM2.5 (mass), PM2.5 (number), PM10 (mass), PM10 (number) EFs developed in this research are between 110-120 mg/g of incense, 2.5-3 mg/g of incense, 800-1100 #particles/µg of incense, 32-33 mg/g of incense, 1200-1400 #particles/µg of incense respectively.
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Moerlein, David T. "Reduction of Harmful Air Pollution: Potential Ability of Different Plant Species to Remove Particulate Matter From Indoor Air". Cincinnati, Ohio : University of Cincinnati, 2005. http://www.ohiolink.edu/etd/view.cgi?acc%5Fnum=ucin1114196167.
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Thesis (M.S.)--University of Cincinnati, 2005.Title from electronic thesis title page (viewed Sept. 10, 2007). Includes abstract. Keywords: biology; phytoremediation; air pollution; plants; particulate matter. Includes bibliographical references.
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Billah, Md Baki. "Chemical and toxicological characterization of chemical contaminants in air pollution particulate matter". HKBU Institutional Repository, 2015. https://repository.hkbu.edu.hk/etd_oa/155.
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In wintertime hazy episodes, the air pollution in northern China has always reached to an alarming level. In the winter of 2012-13, the trans-boundary air pollution from China has attracted national and global attention. An elevated public awareness to the unprecedented pollution levels has prompted much investigation on the health effects of fine particulate matter (PM), in particular PM2.5. Since PM-elicited harmful effects primarily depends on the composition of chemical contaminants adsorbed, in this study we characterized the chemical compositions of PM2.5 and determined its associated toxicity. Samples of PM2.5 were collected using high-volume samplers installed in five northern and southern cities in China. One typical (polycyclic aromatic hydrocarbons, PAHs) and one emerging (perfluorinated compounds, PFCs) family of organic pollutants were analyzed using gas chromatographymass spectrometry (GC-MS) or liquid chromatography-MS-MS (LC-MS-MS), followed by in-vitro or/and in vivo studies. In Chapters 2 and 3, sixteen PAH congeners in PM2.5 samples collected from five different cities (Hong Kong (HK), Guangzhou (GZ), Xiamen (XM), Xi’an (XA) and Beijing (BJ)) in the winter and summer time 2012-13 was analyzed. The biological effects of the sample extracts were determined using the human bronchial epithelial cells BEAS-2B. The total PAH concentrations ranged from 3.35 to 80.45 ng/m3 air, leading by BJ, followed by XA, XM, GZ and HK. In a comparison of the physical and chemical data of the samples obtained during the winter and summer sampling periods, the amount of PM collected per unit time and the concentrations of PAHs adsorbed were found to be remarkably greater in the winter time. In the cell culture study, the expression levels of the pro-inflammatory cytokine (interleukin-6, IL-6) and detoxifying enzymes (i.e. cytochrome p450 enzymes, CYP1A1 and CYP1B1) were found to be stimulated in the treatment. The cells exposed to sample extracts prepared from XA and BJ demonstrated significant migratory activities, indicating a sign of increase of tumorigenicity. These data highlighted the risk of getting lung cancer in local population. In chapters 4 and 5, we focused on the emerging pollutants PFCs, in particular PFOS. Chemical characterization was implemented using the winter samples. Biological effects of PFOS were conducted using omics approach in a maternal-fetal model. Therefore, in the first part of chapter 4, we measured the concentrations of nine PFC congeners in PM2.5 samples using LC-MS-MS. Generally, the eight PFCs, namely PFOS, PFDoA, PFUdA, PFDA, PFNA, PFOA, PFHxA and PFBA were detected in all the sampling cities, with the exception PFHxS which was below the limit of detection. The total PFC concentrations ranged from 121.2 to 192.2pg/m3, leading by GZ, followed by XA, BJ, XM and HK. The data denoted the risk of inhalation exposure to PFCs through PM2.5, which enter into blood circulations via lung alveoli, presumably penetrates through placenta in affecting fetal health. Therefore, in the latter part of chapter 4, the potential adverse effect of prenatal exposure to the prototypical PFC congener PFOS was used in the maternal-fetal mouse model to determine its effects on fetal liver and pancreas. Transcriptomic analysis demonstrated that the in-utero exposure to PFOS affect the expression of genes associated with fatty acid metabolism, lipid transport, and steroid synthesis in fetal livers. KEGG pathway analysis showed these changes were primarily associated with modulations of arachidonic, linoleic acid, retinol metabolism and PPAR signaling pathways in fetal liver. To identify additional target fetal tissue of PFOS, in chapter 5, we investigated the effects of PFOS on the protein expression in fetal pancreas using the technique of “Isobaric tags for relative and absolute quantitation (iTRAQ). We identified changes in the protein expressions involved in pancreatic secretion, protein digestion and absorption, protein processing in endoplasmic reticulum, fat digestion and absorption, glycerolipid metabolism and steroid biosynthesis. The perturbations to these targets may increase the risk of pancreatitis in mouse offspring. Collectively, this study provided a comprehensive chemical and biological analysis of PM2.5 collected in China and demonstrated the toxicities, in vitro and in vivo of the adsorbed chemical contaminants.
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Parker, Gavin James. "Analysis of metals in airborne particulate matter in eastern Iowa". Thesis, University of Iowa, 2019. https://ir.uiowa.edu/etd/7010.
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Airborne particulate matter (PM) consists of solid and liquid particles suspended in air. PM causes many negative health effects when inhaled like exacerbations of asthma, chronic obstructive pulmonary disease (COPD), and premature death. The health impacts of PM depend on the physical size and chemical composition of the inhaled particles. Particles less than 2.5 micrometers can penetrate the deep lung and enter the bloodstream. Understanding the composition of PM helps study human exposures and evaluate PM sources to support control and mitigation strategies. This thesis examines PM in power plant emissions, in ambient air, and in homes, with an emphasis on characterizing hazardous metals.
PM emissions from the University of Iowa power plant were examined during a transition away from coal. Biomass is a renewable fuel and when used in place of or co-fired alongside coal it directly reduces emissions of fossil CO2 and PM to the atmosphere. PM emissions were examined under two scenarios: the first was a stoker boiler that fired 100% renewable energy pellets. PM and metal emissions reduced by 59 and 80% respectively despite increases to polycyclic aromatic hydrocarbons (PAHs) that was attributed to emission of unburned carbon fuel. The second test was done in a circulating fluidized bed boiler firing 78% oat hulls, 17% coal, and 5% energy pellets. Decreases in PM, PAHs, and metal emissions were 32, 33, and 50%, respectively. Reductions in PM, PAHs, and metals when firing renewable fuels provide environmental advantages to local air quality while trying to eliminate the use of coal.
Ambient air quality was examined downwind of the power plant. The levels of PM2.5 in Iowa City in 2016 ranged from 1.4-32.1 µg m-3 with an annual mean of 7.5 µg m-3. These levels are below the National Ambient Air Quality Standards (NAAQS) for 24-hours (35 µg m-3) and the annual average (12 µg m-3). On average, the analyzed metals accounted for 10.7 ± 5.3% of PM2.5. Potassium, calcium, and zinc were the most abundant metals (averaging 250 ± 10, 170 ± 40, and 11.2 ± 0.5 ng m-3, respectively) and are associated with geological sources and biomass burning. Metals associated with fossil fuel combustion such as arsenic, lead, or vanadium were observed at low levels (averaging 0.58 ± 0.01, 1.32 ± 0.03, and 0.19 ± 0.01 ng m 3, respectively). Harmful metals were at least an order of magnitude lower than the World Health Organization’s guideline concentrations in Iowa City PM2.5. Overall, the hazardous metals in ambient PM2.5 observed in Iowa City were not at concerning levels. The work in this chapter helps provide a metal speciation profile for future studies and these measurements can be used to assess future changes in PM2.5 metal concentrations.
Indoor PM collected in homes of Eastern Iowa COPD patients was characterized for its metal content. COPD patients are at higher risk of developing respiratory infections, which cause acute exacerbations of COPD—the leading cause of mortality in COPD patients—and airborne PM increases risk of infection. From the 21 homes studied 6-87 mg of indoor PM was collected over 30 days in winter. Crustal metals such as magnesium, iron, and aluminum were the most concentrated in indoor PM, having mass fractions from 3000-25,000 ng mg-1. Toxic metals like vanadium and arsenic were at lower levels from 3-65 ng mg-1. Between homes the relative abundance of metals was similar, but the absolute abundance was highly variable. Analyzing indoor PM is essential since Americans on average spend 80% of their day indoors making it a significant environment for PM exposure. This chapter provides a chemical profile for different homes when studying the impact PM has on respiratory health.
This thesis also provides new measurements of the chemical composition of PM at the point of emission, in ambient air, and within homes. Advancing knowledge of PM composition in different environments is vital in understanding its impacts on human health. Improvements to local air quality with reductions to PM and metal emissions were observed when firing alternative fuels. Ambient PM2.5 concentrations in Iowa City were lower than NAAQS levels and the composition of both ambient and indoor PM was evaluated. With greater understanding of PM composition, better control strategies can be studied and employed to improve local air quality.
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Portillo, Federico. "Assessment of Ambient Air Particulate Matter in the New Orleans Historic District". ScholarWorks@UNO, 2008. http://scholarworks.uno.edu/td/878.
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Particulate matter in the ambient air of down-town New Orleans, LA, is not currently recorded by any government, state, or private organization. This research quantified particulate matter (PM) and its metal concentration in ambient air of the New Orleans Historic District. Both, PM10 (PM less than 10 micron in size) and PM2.5 (PM less than 2.5 micron in size) were quantified by gravimetric analysis using an Andersen Dichotomous Sampler (Series 240). Posterior to gravimetric analysis, the filters were analyzed with a fluorescent test method using an Innov-X Portable XRF Analyzer (Model A-6500). This study demonstrated that the ambient air of the New Orleans Historic District is in compliance with the National Ambient Ai Quality Standards regarding contamination of particulate matter and Lead.
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Tai, Pui Kuen Amos P. K. "Impact of Climate Change on Fine Particulate Matter \((PM_{2.5})\) Air Quality". Thesis, Harvard University, 2012. http://dissertations.umi.com/gsas.harvard:10576.
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This dissertation investigates the impact of 2000-2050 climate change on fine particulate matter \((PM_{2.5})\) air quality. We first applied a multiple linear regression model to study the correlations of total \(PM_{2.5}\) and its components with meteorological variables using the past decadal \(PM_{2.5}\) observations over the contiguous US. We find that daily variation in meteorology can explain up to 50% of \(PM_{2.5}\) variability. Temperature is positively correlated with sulfate and organic carbon (OC) almost everywhere. The correlation of nitrate with temperature is negative in the Southeast but positive in California and the Great Plains. Relative humidity (RH) is positively correlated with sulfate and nitrate, but negatively with OC. Precipitation is strongly negatively correlated with all \(PM_{2.5}\) components. We then compared the observed correlations of \(PM_{2.5}\) with meteorological variables with results from the GEOS-Chem chemical transport model. The results indicate that most of the correlations of \(PM_{2.5}\) with temperature and RH do not arise from direct dependence but from covariation with synoptic transport. We applied principal component analysis and regression to identify the dominant meteorological modes controlling \(PM_{2.5}\) variability, and showed that 20-40% of the observed \(PM_{2.5}\) daily variability can be explained by a single dominant meteorological mode: cold frontal passages in the eastern US and maritime inflow in the West. From 1999-2010 observations we further showed that interannual variability of annual mean \(PM_{2.5}\) in most of the US is strongly correlated with the synoptic period T of the dominant meteorological mode as diagnosed from a spectral-autoregressive analysis. We then used the observed local \(PM_{2.5}\)-to-period sensitivity to project \(PM_{2.5}\) changes from the 2000-2050 changes in T simulated by fifteen IPCC AR4 GCMs following the SRES A1B scenario. We project a likely increase of \(\sim 0.1 \mu g m^{-3}\) in annual mean \(PM_{2.5}\) in the eastern US arising from less frequent frontal ventilation, and a likely decrease of \(\sim 0.3 \mu g m^{-3}\) in the northwestern US due to more frequent maritime inflows. These circulation-driven changes are relatively small, representing only a minor climate penalty or benefit for \(PM_{2.5}\) regulatory purpose.Engineering and Applied Sciences
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Prasauskas, Tadas. "Air contamination by particulate matter from processes of building refurbishment and operation". Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2015. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20150102_133801-10791.
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People spend major part of their life indoors – at home or in other public or private indoor environments. Clean air in the living environment is very important for the public health. Indoor air quality (IAQ) is largely dependent on the outdoor air quality, due to the continuous indoor air mixing with the ambient air. However, air pollutants in buildings are strongly linked to building indoor factors as well (emissions from building structure, fabrics, coating, furnishing, ventilation system, food preparation, occupant activities etc.). Building renovation is mostly based on economic aspects – performing cost-effective refurbishment actions assuming further savings in energy costs, without taking into account possible changes in air quality conditions. Therefore, a natural question arises whether it will be possible to ensure a comfortable and healthy living for occupants. There is a lack of methodologically robust intervention studies that support the improvement of energy efficiency measures by means of improved IAQ. It is also important to improve the knowledgebase in order to support the implementation of the related policies in Europe. In this context, overview of the results from before and after intervention measurements and emissions from building materials were presented, and the implications on IAQ were discussed. The results of the research provide data for the technical and administrative measures for the improvement of IAQ in residential buildings.Žmonės įprastai praleidžia didžiąją dalį savo laiko patalpose - namuose ar kitų valstybinių ir privačių patalpų aplinkoje. Švaraus oro užtikrinimas gyvenamojoje aplinkoje yra labai svarbus visuomenės sveikatai. Oro teršalai patalpose yra glaudžiai susiję su pastato viduje vykstančiais procesais (emisijos iš pastato konstrukcijos, apdailos medžiagų, buitinių cheminių priemonių, ventiliacijos sistemos, maisto ruošos, gyventojų aktyvumo ir t.t.). Dėl nuolatinio vidaus oro maišymosi su išorės aplinkos oru, patalpų oro kokybė yra taip pat smarkiai įtakojama išorės oro kokybės. Pastatų renovacija daugiausia yra grindžiama ekonominiu aspektu. Atliekant ekonominius pastatų atnaujinimo veiksmus, paremtus didesniu energijos sąnaudų taupymu, neatsižvelgiama į galimus oro kokybės pokyčius. Todėl kyla natūralus klausimas ar po šių procesų pavyks užtikrinti patogią ir sveiką gyvenseną. Šiuo metu yra stygius metodologiškai stiprių mokslinių tyrimų, kurie nagrinėja energijos efektyvumo priemonių didinimo įtaką patalpų oro kokybei. Atsižvelgiant į tai, šiame darbe yra aptariami gauti rezultatai iš oro kokybės tyrimų daugiabučiuose pastatuose jų eksploatacijos metu bei aerozolio dalelių emisijos iš statybinių medžiagų pastato statybos ir atnaujinimo metu. Taip pat parengtos rekomendacijos daugiabučių pastatų atnaujinimui ir eksploatacijai, užtikrinant sveiką patalpų oro kokybę. Tyrimo rezultatai suteikia svarbios informacijos tiek techninėms, tiek ir administracinėms priemonėms, skirtoms... [toliau žr. visą tekstą]
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Kirk, Randall P. "The impact of residential wood combustion on indoor particulate matter levels". Virtual Press, 1988. http://liblink.bsu.edu/uhtbin/catkey/539632.
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This study concentrates on indoor air pollution, specifically particulate matter, as a result of woodburning in the home. Three single-family residences in Richmond, Indiana, equipped with identical airtight woodburning stoves and using a controlled wood supply, were monitored for a 49-day period in 1987. Particluate matter samples were collected during periods of active wood combustion and periods absent of wood combustion using low-volume samplers. Significant differences were found in two of the three houses when wood combustion and non-wood combustion periods were compared. No relationship was found between particle levels and time of day, ambient air temperature, pounds of wood burned, refueling duration or refueling frequency. It was concluded that woodburning can affect the quality of indoor air in particulate matter levels.Department of Natural Resources
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Hagler, Gayle S. W. "Measurement and analysis of ambient atmospheric particulate matter in urban and remote environments". Diss., Available online, Georgia Institute of Technology, 2007, 2007. http://etd.gatech.edu/theses/available/etd-05042007-171845/.
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Thesis (Ph. D.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2007.Weber, Rodney, Committee Member ; Schauer, James, Committee Member ; Mulholland, James, Committee Member ; Bergin, Mike, Committee Chair ; Russell, Armistead, Committee Member.
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Mukota, Tinashe. "Local development and calibration of a passive sampler for monitoring of particulate matter". Diss., University of Pretoria, 2019. http://hdl.handle.net/2263/73458.
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The measurement of ambient particulate concentration (PM10 and PM2.5) using active monitors requires expensive or labour-intensive apparatus or both. Although PM is a priority pollutant, this has precluded widespread or intensive ambient particulate monitoring networks to be set up in South Africa, except in some priority areas. In this study, locally manufactured passive PM monitoring devices (samplers), based on a design initially published by researchers at the University of North Carolina (UNC), were calibrated for the measurement of PM10-2.5. Duplicate samplers of each type (local and UNC) were co-located at eight reference stations equipped with TEOM (Tapered element oscillating microbalance) or BAM (Beta radiation attenuation monitor) particulate monitors in three networks. Imaging of the substrate was carried out using an optical microscope to limit the cost of analysis. The images (10 to 49 per sample) were analysed using both proprietary (Zeiss AxioVision®) and open-source (ImageJ) software at 100X and 200X magnification. Considerable variation exists between the four co-located local and UNC samplers at all stations, although the latter show lesser discrepancies when analysed using the AxioVision software. Greater agreement of the local samplers and the continuous monitors is noted at a 200X and 100X magnification using the AxioVision software with R2 = 0.81 and R2 = 0.79 respectively. The precision of PM10-2.5 measured with the passive samplers was highly variable with calculated CVs ranging from 10.4% to 73.3%. 82% of the CVs were less than 40%. The average CV for all samplers was 34.6%. Passive samplers analysed using the AxioVision software recorded smaller average discrepancies of 45.3% at 100X and 37.3% at 200X magnification. Samplers analysed using ImageJ at 100X magnification exhibited the highest percentage difference from the reference values (81.2%). Using a two factor ANOVA we can show that (at 95% confidence) the analysis software and the imaging magnification have the most significant effect on the calculated sampler concentration results. A disadvantage of passive samplers is large number of days (2-7) required to produce statistically significant values hence disqualifying it for use as a reference method. The device is, therefore, more suitable for screening-level, high spatial density sampling, but some non-regulatory applications are pointed out.Dissertation (MEng)--University of Pretoria, 2019.
Chemical Engineering
MEng (Environmental Engineering)
Unrestricted
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Ong, Chun Hoe. "Electrostatic precipitator to collect large quantities of particulate matter". Thesis, University of Iowa, 2017. https://ir.uiowa.edu/etd/5976.
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Traditional aerosol samplers are limited in their abilities to collect large quantities of particulate matter due to their low flow rates, high pressure drops, and are noise intrusiveness. The goal of this study was to develop an alternate aerosol sampler using electrostatic precipitation technology that was safe and not noise intrusive to be deployed in homes. The O-Ion B-1000 was selected as the most suitable electrostatic precipitator (ESP) for achieving the goal of this study because of its affordability, the design of its collection electrode and its high flow rate. The collection efficiency of the ESP was assessed for three aerosols; Arizona Road Dust (ARD), NaCl and diesel fumes. ARD was found to have the highest average collection efficiency (65%) followed by NaCl (43%) and lastly diesel fumes (41%).
A method for recovering the particulate matter deposited on the collection electrode was developed. The dust collected on the electrode was recovered onto polyvinyl chloride (PVC) filters moistened with deionized water. Additionally, the recovery of the three test aerosols, ARD, NaCl, and diesel fumes, from the collection electrode was assessed. A gravimetric analysis was done to determine the amount of dust recovered. The collection efficiency was used to calculate the amount of mass expected on the filter for a particular aerosol. NaCl had the highest recovery at 95% recovery, followed by ARD (73%) and lastly diesel fumes (50%). Two identical ESPs were also deployed in an office and in a bedroom, 104.47 mg and 9.64 mg of particulate matter (PM) was recovered respectively.
The noise and ozone level produced by the ESP was evaluated to determine the ESP’s viability as a household aerosol sampler. The ESP’s high setting had a noise level of 45.8 dB and ozone generation rate of 0.036 mg/min. The results of the calculation showed that in an averaged size unventilated room (6.10 m × 6.10 m × 2.44 m), it would take 6 hours and 53 minutes for the ozone levels to reach the recommended maximum exposure limits per National Ambient Air Quality Standards (NAAQS). Additionally, a ventilation of 230 L/min is needed in order to prevent the ozone levels generated by the ESP from exceeding maximum exposure limits per NAAQS.
Overall, the O-Ion B-1000 met the criteria of collecting 1 mg of PM in a 24 hour sampling for ARD and NaCl. Diesel fumes however, required 30 hours to collect 1 mg of PM. The noise levels generated by the ESP set on high was one dB above the Environmental Protection Agency (EPA) standards for indoor noise limit. However, the noise is proportional to inverse distance squared; the ESP should not pose a problem during household deployment. Ozone generated by the ESP was also found to be below 0.07 ppm as set by the EPA with an average ventilation of 230 L/min. The average ventilation of a household is 1500 L/min, thus the ozone generated by the ESP would not surpass 0.07 ppm. However, the ESP should not be deployed in unventilated rooms for a period of more than 6 hours and 53 minutes.
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Souza, Milena Gouveia Oliveira de. "Avaliação da concentração de arsênio em partículas fracionadas por tamanho na atmosfera do Recôncavo Baiano". reponame:Repositório Institucional da UFBA, 2011. http://www.repositorio.ufba.br/ri/handle/ri/10027.
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CNPQ
Atualmente, um dos maiores problemas mundiais é a poluição atmosférica, oriunda essencialmente de fontes antrópicas. Os grandes impactos ambientais, como a degradação da qualidade do ar, são resultados dos processos de desenvolvimento urbano e industrial. O material particulado (MP) tem sido alvo de vários estudos devido aos efeitos nocivos causados ao meio ambiente e a saúde humana. O arsênio, um metalóide que apresenta características tanto de metal como de não-metal, é considerado altamente tóxico. A associação do arsênio ao material particulado pode provocar sérios danos à saúde da população. Os níveis de toxicidade do arsênio são dependentes de sua forma química. As espécies inorgânicas de arsênio, arsenito (AsIII) e arseniato (AsV), são também consideradas agentes carcinogênicos. O Recôncavo Baiano é uma região que apresenta grande importância ambiental, social e econômica para o estado da Bahia. Nesta área encontram-se portos, terminais marítimos e diversos pólos industriais que são as principais fontes de emissão de poluentes para o meio ambiente. O presente trabalho teve por objetivo verificar a concentração do arsênio presentes tanto nas partículas finas, quanto nas partículas grossas do material particulado atmosférico do Recôncavo Baiano, para avaliar as contribuições deste poluente à saúde da população exposta. A determinação de arsênio em material particulado, utilizando a digestão, com HNO3, e a técnica de espectrometria de fluorescência atômica acoplada à geração de hidreto (HG-AFS), mostrou-se eficiente para a matriz estudada com limite de detecção e quantificação de 0,3 ng m-3 e 1 ng m-3, respectivamente. As concentrações médias de arsênio, obtidas no material particulado em algumas regiões do Recôncavo Baiano, estavam em torno de 30 ng m-3, valor cinco vezes maior que o recomendado pela União Européia (6 ng m-3). O arsênio presente no material particulado encontra-se substancialmente nas partículas finas. Alertando para os riscos de exposição da população, nos municípios onde foram feitas as amostragens. Os resultados apresentados neste trabalho são indicativos da necessidade de se atualizar os padrões de qualidade do ar para o Brasil, incluindo outros poluentes como o arsênio
Salvador
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McGowan, James Andrew. "Effects of particulate air pollution on cardiorespiratory admissions in Christchurch, NZ". Thesis, University of Canterbury. Mathematics and Statistics, 2000. http://hdl.handle.net/10092/1265.
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Abstract Objective: In Christchurch there is concern that winter air pollution, dominated by particulate matter (PM₁₀) from domestic heating, causes a local increase in cases of cardiorespiratory disease. Our aim was to investigate whether the particulate levels did influence emergency hospital admissions, and if so to what extent. Method: Air pollution and meteorological data was obtained from a Canterbury Regional Council monitoring station. Two local hospitals provided data on emergency admissions for both adults and children with cardiac and respiratory disorders. All data was obtained for the period from June 1988 to December 1998. Missing PM₁₀ data was interpolated from other known pollution values when necessary. The PM₁₀ data was compared to the admissions data using a time series analysis approach, with weather variables controlled for using a generalised additive model. Results: There was a significant association between PM₁₀ levels and cardiorespiratory admissions. For children and adults combined there was a 3.4% increase in respiratory admissions for every interquartile (14.8 µg/m³) increase in PM₁₀. In adults there was a 1.3 % increase in cardiac admissions for each interquartile increase in PM₁₀. There was no relationship between PM₁₀ levels and appendicitis, the condition that we selected to be our control. Conclusion: In Christchurch there is a significant relationship between particulate levels and the admissions for cardiac and respiratory illnesses. The size of the effect is comparable to other international studies, and the greatest impact is seen on the respiratory system.
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Ames, Robin W. "Analysis of a 2007 EPA compliant diesel particulate matter sampling system". Morgantown, W. Va. : [West Virginia University Libraries], 2007. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5245.
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Thesis (M.S.)--West Virginia University, 2007.Title from document title page. Document formatted into pages; contains xv, 133 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 91-95).
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Obenson, Tanyi. "Carbon-Storing Trees and Particulate Matter Reduction in Los Angeles, California". ScholarWorks, 2018. https://scholarworks.waldenu.edu/dissertations/4749.
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Air pollution is a major concern in heavily populated cities such as Los-Angeles, California. Particulate Matter (PM) pollution in Hispanic and Black American neighborhoods in Los Angeles tends to be higher than adjacent non-minority areas. Research has indicated that certain carbon-storing trees can be used to reduce PM pollution. The purpose of this qualitative, interview research project was to determine the feasibility of using carbon-storing trees to reduce PM pollution in Hispanic and Black American neighborhoods in Los Angeles. Using an ecological theoretical framework, 10 subject matter experts were interviewed about their knowledge of carbon-storing properties and the feasibility of planting 10 different types of trees to reduce PM in the target neighborhoods. The results indicated that oak and pine trees are the most feasible in accomplishing PM reduction within the target areas based on factors like leaf structure, size, and adaptation to Southern California climate and soil. The least feasible trees included California sycamore, Fremont cottonwood, ox horn bamboos, American sweetgum, and yellow poplar. Public health officials may use this study's findings to bring social change to communities by encouraging the development and implementation of tree planting plans that may reduce PM pollution for all populations across the United States. The responsibility of implementing a tree planting strategy would be up to city planners and public health officials (stakeholders) in affected communities. To accomplish this, stakeholders would need to determine the financial costs and specific locations for planting oak and pine trees.
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Derneryd, Anna. "Links between ENSO and particulate matter pollution for the city of Christchurch". Thesis, Uppsala universitet, Luft-, vatten och landskapslära, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-303876.
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The purpose of the project has been to investigate how synoptic scale climate systems control the frequency of air pollution episodes in the city of Christchurch, New Zealand. The work has been done at the University of Canterbury, New Zealand, and data from the region has been analysed. Air pollution is, during winter time, a growing problem in Christchurch and the project was initiated by the regional environmental legislative body. The first part of the report is on finding relationships on a local-scale between particulate matter concentrations, ground temperature, temperature at 10 meters and wind speed. The data set used in the analysis comes from a monitoring station in St. Albans, situated in the north-east of Christchurch. In the second part, a connection is made thought correlation calculations between the results from the local-scale analysis and the synoptic situation observed over New Zealand during the same period. Two different data sets have been used in the analysis. One data set includes different weather patterns observed over New Zealand and the other data set includes different zonal and meridional circulation indices. A pressure index is also used, the Southern Oscillation Index. On the local-scale, a relationship has been found between the particulate matter concentration and the number of night hours with an inversion present. A correlation also exists between the wind speed and the number of night hours with an inversion present. The connection to the synoptic scale through cluster frequencies and circulation indices was found to be divergent. The cluster frequency analysis indicates on a direct correlation between the Southern Oscillation Index and the air pollution concentration in Christchurch, while the circulation indices analysis indicates on an inverse relationship between the Southern Oscillation Index and the air pollution concentration in Christchurch.Sammanfattning av ”Kopplingen mellan ENSO och aerosoler mindre än 10 μm i Christchurch” Avsikten med projektet har varit att undersöka om det finns ett samband mellan storskaliga vädersystem (synoptisk skala) och antalet lokalt inträffade händelser med höga halter av luftföroreningar. Arbetet har utförts vid University of Canterbury i Christchurch på Nya Zeeland och mätdata för denna region har analyserats. Luftföroreningar är här ett växande problem, speciellt vintertid, vilket de regionala lagstiftande myndigheterna har identifierat och önskat få utrett. I första delen av rapporten analyseras samband mellan lokala parametrar, så som temperatur vid marknivå och på 10 meters höjd, vindhastighet och koncentrationen av olika luftföroreningar. Data som använts i dessa analyser har uppmätts vid en mätstation placerad i St. Albans, vilken ligger i nordöstra delen av centrala Christchurch. I den andra delen av rapporten beräknas korrelationen mellan resultaten från den lokala analysen och olika synoptiska vädersituationer observerade över Nya Zeeland under motsvarande tidsperioder. Två databaser har använts vid analysen, dels en databas innehållande olika vädersituationer över Nya Zeeland och dels en innehållande olika cirkulationsindex. Dessutom användes också ett lufttrycksindex, ”The Southern Oscillation Index”. Två korrelationer har beräknats i den lokala analysdelen. Dels har ett samband mellan luftföroreningskoncentrationen och antalet timmar med en inversion närvarande nattetid beräknats samt en korrelation mellan vindhastighet och antalet timmar med en inversion närvarande nattetid. Kopplingen till den synoptiska skalan visar på två divergerande resultat. Analys genomförd med olika ”clusters” visar på ett direkt samband mellan ”The Southern Oscillaion Index” och luftföroreningskoncentrationen i Christchurch medan en analys genomförd för circulationsindex visar på ett omvänt samband mellan ”The Southern Oscillation Index” och luftföroreningskoncentrationen i Christchurch.
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Chan, Sik-foon Joyce, i 陳錫歡. "Application of cluster analysis to identify sources of particulate matter in Hong Kong". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1995. http://hub.hku.hk/bib/B31253076.
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Ferreira, Martins Vânia. "Air quality in subway systems: particulate matter concentrations, chemical composition, sources and personal exposure". Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/399787.
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Air quality sampling campaigns both on platforms and inside trains of three European subway systems (Barcelona, Athens and Oporto) were conducted in order to characterise PM, investigating its variability, to better understand the main factors controlling it, and therefore the way to improve air quality.
PM concentrations varied among the European subway platforms, and also within the same underground system, mainly associated to differences in the design of the stations and tunnels; system age; train frequency; ventilation and air-conditioning systems; passenger densities; power system (catenary vs. third rail); composition of wheels, rail tracks, brake pads and power supply materials; rail tracks geometry (curved vs. straight and sloped vs. levelled); and outdoor air quality. PM concentrations displayed clear diurnal patterns among the three European subway platforms, depending largely on the operation and frequency of the trains and the ventilation system.
In the Barcelona subway system, the new stations showed on average lower PM concentrations than those in the old conventional stations, mainly related to the stations design (with platform screen door systems), but also due to the lower train frequency and more advanced ventilation setup. Furthermore, PM concentrations on the platforms in the colder period were higher than in the warmer period, mainly due to weaker ventilation during the colder period. In Athens, the mean PM concentrations in a new station located in the periphery of the line were lower than in a central station, attributed not only to the age and location of the station, but also to the lower train frequency.
Measurements carried out in the three subway systems performed on stations with similar platform design were compared. The highest PM concentrations were observed in the Oporto subway station because the line is composed by curved and/or sloping rail tracks (resulting in a higher emission of rail wear particles) and it has a higher train frequency. Furthermore, mechanical forced ventilation is inexistent in this subway system.
The use of air-conditioning inside the trains was an effective approach to reduce exposure levels, being more efficient removing coarser particles. Having the carriage windows open promotes the entrance of polluted air from tunnels and platforms into
the trains. Nevertheless, even when the carriage windows are closed and the air conditioning system is switched on, the PM concentrations inside the trains continue to be greatly affected by the surrounding air quality conditions.
Despite the lower PM2.5 (PM with aerodynamic diameter <2.5 µm) concentrations with respect to those on station platforms, the highest dose was observed inside the trains due to the longer exposure time. Overall, during a subway commuting travel, roughly 80% of the inhaled mass of subway PM2.5 was deposited in the respiratory tract. The dose, and its distribution on the different regions of the respiratory tract, is mainly dependent on the particle size and exposure concentrations.
Chemically, subway PM2.5 on the platforms is comprised of iron, total carbon, crustal matter, secondary inorganic compounds, insoluble sulphate, halite and trace elements. Fe was the most abundant element in PM2.5 found on the platforms, with relative contribution to the bulk PM2.5 ranging from 19 to 46%, which is generated mainly from mechanical wear and friction processes at rail-wheel-brake interfaces. The trace elements with highest enrichment in the subway PM2.5 were Ba, Cu, Mn, Zn, Cr, Sb, Sr, Ni, Sn, As, Co and Zr. Differences in metal concentrations in PM among the stations and subway systems might be associated to the different chemical composition of wheels, rails, brakes, and power supply materials.
A source apportionment analysis allowed the identification of outdoor (sea salt, fuel oil combustion and secondary) and subway sources on platforms, the latter including all emissions generated within the subway system.
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Gorr, Matthew W. "Air Pollution and Cardiovascular Dysfunction". The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1428674045.
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Válio, Vinícius Mori. "Análise do material particulado atmosférico em uma região de São Carlos-SP". Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-13082015-144101/.
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O presente trabalho avaliou a qualidade do ar de uma área central da cidade de São Carlos-SP, mais precisamente no campus 1 da Universidade de São Paulo. Nessa região há grande movimentação de pessoas e veículos, principalmente durante o horário comercial. Esta avaliação foi feita com base na determinação de um dos parâmetros utilizados para verificar a qualidade do ar, o material particulado (MP) inalável em suspensão, ou seja, partículas que possuem diâmetro aerodinâmico menor ou igual a 10 μm e podem penetrar no sistema respiratório, sendo portanto, nocivas à saúde humana. O MP foi determinado em suas frações de 2,5 e 10 μm de diâmetro (MP10 e MP2,5). Duas metodologias diferentes foram utilizadas para determinar a concentração do material particulado em suspensão, fotometria por espalhamento de luz, através do equipamento ADR-1500 e gravimetria, através do PEM (Personal Enviromental Monitor). Os valores obtidos pelo método gravimétrico foram superiores aos resultados encontrados através da fotometria. As concentrações obtidas foram comparadas com os limites recomendados pela Organização Mundial da Saúde para o MP em suas frações de 2,5 e 10 μm, iguais respectivamente a 25 e 50 μg/m3. Além do material particulado foram obtidos dados para temperatura, umidade relativa e precipitação. As médias obtidas para as concentrações de MP10 e MP2,5, com o método gravimétrico, o qual fornece os resultados mais confiáveis, foram iguais respectivamente a 48,8 e 23,1 μg/m3, muito próximas portanto, de seus limites correspondentes. As menores concentrações obtidas para o MP10 foram, em sua maioria, verificadas em dias chuvosos, tanto através do PEM como do ADR. As concentrações de MP2,5, obtidas somente através do PEM, também apresentaram os menores valores em dias com chuva. Foi desenvolvido um modelo matemático que prevê o comportamento do MP10 durante as precipitações, evento este que se mostrou o mais importante na influência da concentração de material particulado atmosférico.This study evaluated the air quality of a central area of the city São Carlos-SP, more precisely on the Campus 1 of the University of São Paulo. In this region there is a large movement of people and vehicles, manly during business hours. This evaluation was made based on determination of one parameter used to verify air quality, the inhalable particulate material (PM) suspended in the air, in other words, particles which have aerodynamic diameter less or equal to 10 μm and can penetrate in the respiratory system, therefore, harmful to human health. The PM was determined in its fractions from 2,5 and 10 μm of diameter (PM10 e PM2,5).). Two different methodologies were used to determinate the concentration of particulate suspended material, photometry by scattered light, using the equipment ADR-1500, and gravimetry, thru PEM (Personal Environmental Monitor). The data obtained from gravimetry were higher than the results found thru photometry. The concentrations found were compared to the limits recommended by World Health Organization for PM and its fractions of 2,5 and 10 μm, equal to 25 and 50 μg/m3. Besides PM, temperature, relative humidity and precipitation were measured. The average values for the concentrations of PM10 and PM2,5 , using gravimetry, which provide more reliable results, it were equal to 48,8 and 23,1 μg/m3, therefore really close to their corresponding limits. The lower concentrations seen for PM10 were, mostly, verified on rainy days, using PEM and ADR. The concentrations of PM2,5 , obtained just using PEM, also had the lowest values during rainy days. A mathematical model was developed to predict PM10 behavior during precipitations, this event has shown to have the most important influence on the concentration of atmospheric particulate matter.
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Chan, Yiu-chung, i n/a. "Identification of Sources of PM2.5 and PM10 Aerosols in Brisbane". Griffith University. Australian School of Environmental Studies, 1997. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20050906.093804.
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Urban health problems and visibility degradation problems are associated with particulate matter in the air, especially PM10 and PM25 (particles with aerodynamic diameter less than 10 j.tm and 2.5 jsm, respectively). The aim of this study was to investigate the characteristics and sources of PM25 and PM20 aerosols in Brisbane. This study collected aerosol samples over a period of two and a half years at five sites around Brisbane. Source samples of soil dusts, road-side dusts and sea salt were also collected and analysed to provide information on source emission composition. The aerosol samples were analysed by a wide range of techniques, including Ion Beam Analysis and Scanning Electron Microscopy, for their chemical composition and particle size distribution. Some methodologies have been specifically developed in this study. The results presented here show that the chemical composition of PM20 aerosols in Brisbane varies largely with particle size and locations. The chemical composition of the samples are generally related to the land use near the monitoring sites. On average, the major components in the PM10 aerosol samples at five sites in Brisbane were identified as: crustal matter (27% by mass), organic matter (16%), sea salt (12%), soot (11%), and ammonium sulphate (7%). Among the Australian studies, in general, the results show that the composition of the PM25 aerosol samples collected at the Griffith University site (Brisbane) is closest to those of the New South Wales samples. The samples from Melbourne and Perth are generally richer in industry-and vehicle-related species. The major components of the PM25 aerosols at the GU site were identified as: organic matter (27% by mass), elemental carbon (23%), ammonium sulphate (14%), sea salt (9%) and crustal matter (6%). The results show that contribution of emission sources also has large particle size, temporal and spatial variations. Based on the results of source apportionment from the chemical mass balance method, the major contributors of PM20 aerosol mass in samples collected at five sites in Brisbane were found to include: soiL/road-side dusts (25% by mass, results of analysis also indicate a higher contribution from road-side dusts than from soil dusts), motor vehicle exhausts (13%, more than 80% of which are from diesel trucks/buses), elemental carbon and secondary products (around 15%), sea salt (12%), Ca/Ti-rich compounds from cement plant and mineral processing industries (11%), and biomass burning and bioaerosols (7%). On average, the PM25 aerosol mass at the Griffith University (GU) site was found to have contributions mainly from sources related to combustion. These sources include elemental carbon (24% by mass), secondary organics (21%), biomass burning (15%) and secondary sulphate (14%). Although motor vehicle exhausts contribute directly to only 6% of the PM25 aerosol mass at the GU site, their actual contribution could be substantial because most of the elemental carbon and secondary products are related to motor vehcile exhausts. On average, the results show that the visibility degradation problems in Brisbane are worse in winter/autumn than in summer. Soot and sulphate particles are the main visibility degrading species. In terms of visibility degrading sources, the main contributors are (excluding the contribution of NO2 gas): motor vehicles (up to 50%, including the secondary products), secondary sulphates (17%) and biomass burning (10%). In general, emission sources which contribute more to the fine particle fraction, and to gaseous pollutants, are most responsible for the aerosol associated health problems and visibility degradation problems. In Brisbane, these sources include motor vehicle exhausts, soil dusts, biomass burning and industrial dust.
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Ramires, Letícia Ogushi Romeiro. "Análise da fonte e composição da poluição atmosférica em diferentes locais da região metropolitana de São Paulo". Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-27032013-094910/.
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Grandes cidades, como São Paulo, são afetadas de forma significante pela poluição atmosférica. É de grande importância a caracterização das fontes emissoras da poluição atmosférica, não somente nas regiões centrais, mas também nas regiões periféricas, pois a composição da poluição pode não ser homogênea em toda a extensão da cidade. Neste estudo foram caracterizados os componentes da poluição atmosférica em quatro regiões dentro cidade de São Paulo. Para este fim foram Coletados Material Particulado (PM2.5) durante vinte dias no período de inverno de 2011 e vinte dias durante o período de verão de 2011. O material foi coletado através de filtros de policarbonato com 24 h de exposição, e foi submetido a análises gravimétricas, determinação da concentração de Black Carbon por refletância e determinação da composição elementar por Fluorescência de Raios-X. A identificação das diferentes fontes geradoras de material particulado foi baseada na análise de Componentes Principais (ACP). A variação da concentração da massa do material particulado fino (PM2.5) em g/m3 não teve diferença significativa entre os locais amostrados, mas mostrou diferença entre as estações do ano, sendo maior no período do inverno em todos os locais. A proporção do Black Carbon teve um comportamento diferente da massa. O Black Carbon não variou significantemente entre as estações do ano, porém apresentou diferença entre os locais amostrados, destacando-se no Parque do Ibirapuera e na Zona Leste. Foram encontrados 3 Fatores que explicam 75% da variabilidade. O Fator 1 é constituído pelos elementos Ti, V, Mn, Fe, Ni, Pb, P, S Cr e K e foi atribuído como sendo associado à ressuspensão de solo e emissões veiculares, O Fator 2 é composto por V, P, BC, e S e foi interpretado como sendo representativo de emissões veiculares de combustíveis com alto teor de enxofre. O Fator 3 é 7 associado aos elementos BC e Ni e foi interpretado como sendo produzido por emissões veiculares em geralLarge cities such as São Paulo are significantly affected by air pollution. It is of great importance to characterize the emission sources of air pollution, not only in the central regions of the city of São Paulo, but also in peripheral regions, do to the fact that the composition of pollution may not be homogeneous across the city area. This study shows the Characterized the components of air pollution in four different areas of the metropolitan region of São Paulo. Particulate matter (PM 2.5) was collected during the winter of 2011 and summer of 2011. It was collected 24-h PM2.5 samples, employing gravimetry to determine PM2.5 mass concentrations; reflectance to quantify black carbon concentrations and X-ray fluorescence to characterize elemental composition. A receiver model based on principal component analysis (PCA) was used to identify the involvement of the different sources for the generation of particulate matter. The fine particulate matter (PM2.5) in g/m3 did not differ significantly among the locations. However, the results collected showed differences according the seasons evaluation, being higher in the winter for all regions sampled. The proportion of Black Carbon behaves differently than the mass. It does not vary significantly between the seasons, but between the different regions. The proportion of Black Carbon was higher in Ibirapuera Park and the East Zone. Was found 3 factors explaining 75% of the variability. Factor 1 consists of the elements Ti, V, Mn, Fe, Ni, Pb, P, S Cr e K and was related to crustal emission (soil) and vehicle emissions, Factors 2 consists of the elements V, P, BC, e S and can be related to vehicular emissions of fuels with high sulfur content. Factor 3 consists of the elements BC and Ni was associated to vehicle emission
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Barath, Stefan, Nicholas L. Mills, Ellinor Ädelroth, Anna-Carin Olin i Anders Blomberg. "Diesel exhaust but not ozone increases fraction of exhaled nitric oxide in a randomized controlled experimental exposure study of healthy human subjects". Umeå universitet, Medicin, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-71312.
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Background: Fraction of exhaled nitric oxide (FENO) is a promising non-invasive index of airway inflammation that may be used to assess respiratory effects of air pollution. We evaluated FENO as a measure of airway inflammation after controlled exposure to diesel exhaust or ozone. Methods: Healthy volunteers were exposed to either diesel exhaust (particle concentration 300 mu g/m(3)) and filtered air for one hour, or ozone (300 ppb) and filtered air for 75 minutes. FENO was measured in duplicate at expiratory flow rates of 10, 50, 100 and 270 mL/s before, 6 and 24 hours after each exposure. Results: Exposure to diesel exhaust increased FENO at 6 hours compared with air at expiratory flow rates of 10 mL/s (p = 0.01) and at 50 mL/s (p = 0.011), but FENO did not differ significantly at higher flow rates. Increases in FENO following diesel exhaust were attenuated at 24 hours. Ozone did not affect FENO at any flow rate or time point. Conclusions: Exposure to diesel exhaust, but not ozone, increased FENO concentrations in healthy subjects. Differences in the induction of airway inflammation may explain divergent responses to diesel exhaust and ozone, with implications for the use of FENO as an index of exposure to air pollution.
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Maier, Marissa Leigh. "Application of an ensemble-trained source apportionment method to speciated pm2.5 data at the st. louis midwest supersite". Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/44755.
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Four receptor models and a chemical transport model were used to quantify the sources of PM2.5 impacting the St. Louis Supersite (STL-SS) between June 2001 and May 2003. The receptor models utilized two independent datasets, one that included ions and trace elements and a second that incorporated 1-in-6 day organic molecular marker data. Since each source apportionment (SA) technique has its own limitations, this work compared the results of five different SA approaches to better understand the biases and limitations of each. The source impacts predicted by these five models were then integrated into an ensemble-trained SA methodology. The ensemble method offered several improvements over the five individual SA techniques. Primarily, the ensemble method calculated source impacts on days when individual models either did not converge to a solution or did not have adequate input data to develop source impact estimates. Additionally, the ensemble method resulted in fewer days on which major emissions sources (e.g., secondary organic carbon and diesel vehicles) were estimated to have either a zero or negative impact on PM2.5 concentrations at the STL-SS. When compared with a traditional chemical mass balance (CMB) approach using measurement-based source profiles (MBSPs), the ensemble method was associated with better fit statistics, including reduced chi-squared values and improved PM2.5 mass reconstruction.
A comparison of the different modeling techniques also revealed some of the subjectivities associated with applying specific SA models to the STL-SS dataset. For instance, positive matrix factorization (PMF) results were very sensitive to both the fitting species and number of factors selected for the analysis, whereas source impacts predicted in CMB were sensitive to the selection of source profiles to represent local metals processing emissions. Additionally, the different SA approaches predicted different impacts for the same source on a given day, with correlation coefficients ranging from 0.03 to 0.66 for gasoline vehicle, -0.51 to 0.85 for diesel vehicles, -0.29 to 0.86 for dust, -0.34 to 0.76 for biomass burning, 0.22 to 0.72 for metals processing, and -0.70 to 0.68 for secondary organic carbon. These issues emphasized the value of using several different SA techniques at a given receptor site, either by comparing source impacts predicted by different models or by utilizing an ensemble-trained SA technique.
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Wanjura, John David. "Engineering approaches to address erros in measured and predicted particulate matter concentrations". Texas A&M University, 2003. http://hdl.handle.net/1969.1/3992.
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Some of the air pollution regulations in the United States are based on an
application of the National Ambient Air Quality Standards at the property line.
Agricultural operations such as cotton gins, feed mills, and cattle feed yards may be
inappropriately regulated by such regulations if the current methods of measuring and
predicting the concentrations of regulated pollutants are used. The regulated particulate
matter pollutants are those with aerodynamic equivalent diameters less than or equal to a
nominal 10 and 2.5 micrometers (PM10 and PM2.5) respectively.
The current Federal Reference Method PM10 and PM2.5 samplers exhibit oversampling
errors when sampling dusts with particle size distributions similar to those of
agricultural sources. These errors are due to the interaction of the performance
characteristics of the sampler with the particle size distribution of the dust being
sampled. The results of this work demonstrate the development of a new sampler that
may be used to accurately sample total suspended particulate (TSP) concentrations. The
particle size distribution of TSP samples can be obtained and used to more accurately
determine PM10 and PM2.5 concentrations. The results of this work indicate that accurate
measures of TSP can be taken on a low volume basis. This work also shows that the low
volume samplers provide advantages in maintaining more consistent sampling flow
rates, and more robust measurements of TSP concentrations in high dust concentrations.
The EPA approved dispersion model most commonly used to estimate
concentrations downwind from a stationary source is the Industrial Source Complex
Short Term version 3 (ISCST3). ISCST3 is known to over-predict downwind
concentrations from low level point sources. The results of this research show that the
magnitude of these errors could be as much as 250%. A new approach to correcting
these errors using the power law with P values as a function of stability class and
downwind distance is demonstrated. Correcting the results of ISCST3 using this new
approach results in an average estimated concentration reduction factor of 2.3.
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Orru, Hans. "Exposure to particulate matter and the related health impacts in major Estonian cities". Doctoral thesis, Umeå : Occupational and Environmental Medicine, Umeå University, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-29769.
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Whelan, Paul. "Raman microscopy studies of carbon particles from diesel particulate matter (DPM) and coal dust". Thesis, Sheffield Hallam University, 2001. http://shura.shu.ac.uk/17384/.
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Diesel Particulate Matter (DPM) and coal dust samples were characterised using Raman microscopy, X-ray Photoelectron Spectroscopy (XPS), Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS), Thermo-Gravimetric Analysis (TGA), X-ray Fluorescence (XRF) spectrometry and Scanning electron Microscopy. The sp2/sp3 carbon bonding ratios for DPM and coal dust were determined as 6.1 and 0.7, respectively, from XPS. Principal Component Analysis (PCA) was successfully implemented as a tool for distinguishing between the very similar DPM and coal dust Raman spectra, with over 99% of the variance contained in the first principal component. DPM and coal dust mixtures with known compositions were produced. Raman instrumental parameters were systematically optimised by varying the objective lenses, acquisition times and laser powers, to improve spectral and obtain the most reproducible integrated spectral areas. A rotation stage was developed and employed to spin the specimens during analysis, resulting in a larger sampling area. This resulted in a more representative sampling regime for the heterogeneous specimens and a considerable improvement in the reproducibility of integrated spectral areas. The error in the integrated spectral areas of 10 replicate spectra of different mixtures ranged from 5-22% before implementation of the rotating stage and was notably reduced to 2 -6% due to the action of spinning. Raman spectra of mixtures were used to construct a Partial Least Squares (PLS) model. The R2 values for the DPM and coal dust were 0.865 and 0.763, respectively. The differential bum-off of volatile organics during the Raman analysis due to localised heating from the laser hindered the ability to gain highly reproducible spectra and thus markedly affected the PLS model. A method development stage aimed at improving the R2 values was applied to the samples. This involved heat-treating the specimens to 625°C in an inert nitrogen atmosphere, before the Raman analysis. The resultant PLS model, after heat-treatment, dramatically improved the R2 values such that the DPM and coal dust were 0.974 and 0.907, respectively. This model was used to predict the composition of a test sample with known amounts of DPM and coal dust. The concentrations predicted by the model were 166 ± 3.9pg for the DPM and 68 ± 7.8jxg for the coal dust. The model slightly overestimated the amount of DPM present in the sample but gave a large underestimation of the coal dust content. The diagnostics of the model were investigated and recommendations for the improvement of future models were given.
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MANUZON, RODERICK BEROIN. "Electrostatic Precipitation Technologies for the Mitigation of Particulate Matter Emissions from Poultry Facilities". The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1345562603.
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Garcia, Nancy. "Analysis of number and mass concentration of coarse and fine particulate matter measurements within a heavy-duty diesel truck stop". To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2008. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
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Pires, Adriana. "Efeito da exposição ao material particulado (PM2,5) da poluição atmosférica na espermatogênese de duas gerações de camundongos". Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/5/5144/tde-09122009-154418/.
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Este trabalho caracteriza os efeitos das condições reais de exposição ao material particulado urbano na espermatogênese por meio de análises histológicas de testículos de duas gerações de camundongos BALB/c durante o período gestacional, pósgestacional ou em ambos os momentos combinados. A geração parental foi exposta à poluição do ar em câmaras com ou sem filtros para PM2,5 (câmaras filtrada e não filtrada, respectivamente) por 4 meses, formando dois grupos: não exposto; e exposto. Estes animais foram acasalados e a freqüência do plug vaginal apresentou tendência de queda nas fêmeas expostas (p>0,05). O número de fêmeas prenhes também foi reduzido (p=0,007) e o número de nativivos foi menor na câmara não filtrada (186) quando comparada com a filtrada (268), contudo, o número de animais por ninhada não foi alterado (p>0,05). Após o acasalamento os machos foram eutanasiados, seus testículos pesados, fixados em solução de Bouin ou paraformaldeído 4% e corados com HE, PCNA, Ki67 ou TUNEL. Metade dos animais produzidos na primeira geração, constituída de animais de 1 dia de vida, foi transferida de uma câmara para outra formando os grupos pré-natal e pós-natal. Os animais remanescentes das câmaras filtrada e não filtrada constituíram os grupos não exposto e pré+pós-natal, respectivamente. Após 90 dias, os animais da primeira geração foram eutanasiados e seus testículos foram retirados, pesados, fixados e corados da mesma forma que sua geração parental. Os animais expostos ao PM2,5 da geração parental apresentaram aumento do peso dos testículos (p=0,002), dos epidídimos (p<0,001) e do peso relativo testículo/corpo (p=0,003), epidídimo/corpo (p=0,001). Não houve alteração no número de células germinativas e somáticas e nem na proliferação celular (p>0,05). A apoptose pela coloração de HE foi reduzida no estádio IV (p=0,046) e aumentada no estádio VIII (p=0,019) da espermatogênese. Pela técnica de TUNEL os estádios IV (p=0,017), V (p=0,035) e VIII (p=0,024) mostraram apoptose menor nos animais do grupo exposto. O estádio IV foi identificado como o de maior apoptose espontânea nas duas técnicas empregadas, HE (p<0,001); e TUNEL (p<0,001), entre os animais não expostos. O ciclo do epitélio seminífero foi alterado com freqüência reduzida do estádio IV entre os animais expostos (p=0,005). Os animais da primeira geração expostos no período pré-natal apresentaram redução de peso corpóreo (p<0,001) e dos testículos (p=0,012), bem como, aumento do peso relativo testículos/corpo (p=0,013). O número de células somáticas não foi alterado, mas o de espermatócitos nos grupos pós-natal (p=0,011) e pré+pós-natal foi aumentado (p=0,035) enquanto nos grupos pré-natal e pós-natal houve redução no número de espermátides alongadas (p<0,001). Não houve diferença significativa na taxa de proliferação, apoptose e freqüência dos estádios do ciclo do epitélio seminífero entre os grupos de exposição (p>0,05). O estádio IV mostrou-se o mais sensível para a ocorrência de apoptose espontânea nas duas técnicas empregadas: HE (p<0,001); e TUNEL (p<0,001). A freqüência normal dos estádios entre os animais não expostos mostrou que os estádios finais são os mais freqüentes (VI, VIII e VII, nesta ordem) e os iniciais os menos freqüentes (II e I, nesta ordem) para ambas as gerações. Estes resultados fornecem dados que sugerem que o PM2.5 da poluição atmosférica urbana é capaz de alterar o sistema reprodutivo masculino e a espermatogênese não dependendo do período da vida (durante ou após a gestação) em que os animais são expostos.The present paper describes the effects of real exposure to urban PM2.5 on spermatogenesis by histological analysis of testes of mice (BALB/c) from two generations during fetal or postnatal phases of development and of mice exposed in both phases of development. Parental generations (BALB/c mice) were exposed to air pollution in chambers with or without filters for PM2.5 for 4 months (filtered and non-filtered chambers, respectively), forming two groups, namely non-exposed and exposed. These animals were mated and a frequency of decrease on vaginal plug in the exposed females was observed (p>0.05). The number of pregnant females was reduced as well (p=0.007) and the number of born alive decreased in the non-filtered chamber (186) when compared to the filtered chamber (268); however, the litter size was not altered (p>0.05). After mating, the male were killed, their testes were weighed and fixed in Bouins solution or 4% paraformaldehyde and stained in H&E, PCNA, Ki67 or TUNEL. Half of 1-day old offspring was crossed over between chambers forming the prenatal and postnatal groups; remaining offspring from filtered and non-filtered chambers comprised the non-exposed and pre+postnatally exposed groups, respectively. After 90 days, the animals from first generation were killed and their testes were removed, weighed, fixed and stained like the parental generation. The animals exposed to PM2.5 from the parental generation showed increased testis weight (p=0.002), epididymis weight (p<0.001), relative testis weight (p=0.003), and relative epididymis weight (p=0.001). The germ and somatic cells number was not reduced, and neither was cell proliferation (p>0.05). The apoptosis labeled by H&E was reduced in stage IV (p=0.046) and increased in stage VIII (p=0.019) of spermatogenesis. By using the TUNEL technique, stages IV (p=0.017), V (p=0.035) and VIII (p=0.024) showed fewer apoptosis in the exposed animal group. Stage IV was identified as the most spontaneous apoptosis in both methods: HE (p<0.001) and TUNEL (p<0.001), among the non-exposed animals. The cycle of the seminiferous epithelium was altered with reduced frequency of stage IV between the exposed animals (p=0.005). The animals from the first generation exposed during the prenatal period had a reduced body (p<0.001) and testis weight (p=0.012) and an increased relative testis weight (p=0.013). Differences in germ cell proliferation, apoptosis, and staging were not significantly different among treatment groups (p>0.05). Nevertheless, germ cell populations of post- (p=0.011) and pre+postnatally (p=0.035) PM-exposed animals contained an increased percentage of spermatocytes, while pre- and postnatal groups (p<0.001) had a reduced number of elongated spermatids. Stage IV was shown to be the most sensitive for the occurrence of spontaneous apoptosis in both methods used: H&E (p<0.001); and TUNEL (p<0.001). The normal frequency of the stages between non-exposed animals showed that the final stages are more frequent (VI, VIII e VII) and the beginning stages less frequent (II e I) to both generations. These results suggest that PM2.5 from urban air pollution is capable of altering the male reproductive system and spermatogenesis independently of the period of life when the animals are exposed to it (during or after pregnancy).
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Ying, Qi. "Regional source-oriented air quality model for the apportionment of secondary particulate matter and visibility /". For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2004. http://uclibs.org/PID/11984.
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Serra, Stefania <1985>. "Air Pollution and Human Health Risk: Evaluation of Carcinogenic Potential of Urban Airborne Particulate Matter". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7364/.
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Urban airborne particulate matter (PM) is known to increase morbidity and mortality due to cardiopulmonary diseases related to inflammatory processes and genotoxic effects.
The aim of this thesis is to highlight the toxic and carcinogenic potential of airborne particulate matters collected during different seasons at a site that is located in the northern area of the city of Bologna by using alternative in vitro tests, such as the cell transformation assay with BALB/c 3T3 A31-1-1 and Bhas 42 cells. The purpose is also to evaluate the lifetime cancer risks associated with air inhalation in different sites (rural and urban), by using the relative potency of compounds belonging to the same chemical class (PAHs and nitro-PAHs) and the specific unit of carcinogenic risk.
None of the organic or inorganic extracts of PM2.5 and PM1 induced a significant increase in the average number of transformed foci/plate or in the transformation frequency of BALB/c 3T3 A311-1 cells, whereas the results obtained by Bhas 42 cell transformation showed a significant increase in the average number of transformed foci/plate. All the analyzed organic extracts showed promoting effects in Bhas 42 cells.
The application of the UR cancer risk to the transformed value of B(a)P equivalents in the winter– autumn campaigns leads to estimate an increase in the cancer risk similar to that defined in the literature (1 x 10-4 for exposure to 1 ng/m3). The calculated cancer risk was about one order of magnitude lower in the summer campaigns.
In conclusion, the proposed approach, based on the integration of the data derived from in vitro testing and cancer risk assessment, could represent a reliable model for investigating environmental mixtures and predicting their effects on toxicological relevant endpoints.
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Tranfield, Erin M. "Atherosclerotic plaque ultrastructure following exposure of Watanabe heritable hyperlipidemic rabbits to particulate matter air pollution". Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/31699.
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Epidemiological studies indicate that acute cardiovascular events follow exposure to particulate matter air pollution (PM₁₀) and preliminary animal studies have associated repeated PM₁₀ exposure with progressive changes in atherosclerotic plaques. The unexplored questions are those addressing the precise physiological and pathological cellular mechanisms that may account for the positive association between cardiopulmonary morbidity and mortality and PM₁₀ exposure. The overarching objective of these studies was to examine atherosclerotic plaques from rabbits exposed to PM₁₀ for morphological signs of remodelling and reorganization, with particular emphasis placed on the integrity of the endothelium and its underlying extracellular matrix; the cell population subtending the endothelium; and evidence of cap remodelling and destabilization. Watanabe heritable hyperlipidemic rabbits were exposed to 5 mg of urban PM₁₀ (EHC-93) (n = 8) or saline alone (n = 8) by instillation down the upper airways twice per week for four weeks. Following sacrifice, the abdominal aorta was processed for light and electron microscopy. Light microscopy and transmission electron microscopy qualitative and quantitative analyses were done on tissues processed for transmission electron microscopy. Samples were also processed for and analyzed using scanning electron microscopy. Light microscopy imaging revealed a significant accumulation of macrophage-derived foam cells immediately below the plaque endothelium of WHHL rabbits repeatedly exposed to PM₁₀ (p = 0.04). Qualitative electron microscopy observations showed an organizational change to the atherosclerotic plaques of PM₁₀ exposed WHHL rabbits evidenced by reduced plaque stratification, an absence of a distinct necrotic core and increased macrophage-derived foam cells subtending the endothelium. Using both 2- and 3-dimensional analyses, electron microscopy investigations demonstrated that the insinuation of macrophage-derived foam cells immediately below the endothelium of atherosclerotic caps of PM₁₀ exposed rabbits was associated with the separation of the endothelium from the reticulum of dense ECM (p < 0.0001), fragmentation of the reticulum of dense ECM and a significant increase in endothelial contact with macrophage-derived foam cells (p < 0.0039). Scanning electron microscopy analysis of plaques from control and PM₁₀ treated WHHL rabbits revealed intense leukocyte adhesion and emigration over the plaque core of the PM₁₀ exposed rabbits. As expected, leukocyte adhesion and transmigration were observed at the shoulder regions of atherosclerotic plaques from both control rabbits and PM₁₀ exposed rabbits and the surface morphology of the endothelium differed between the normal blood vessel wall and areas of atherosclerotic disease. PM₁₀ exposure promotes atherosclerotic plaque destabilization by the migration of macrophage-derived foam cells from the core of the atherosclerotic plaque, to the atherosclerotic cap regions and even into the systemic circulation. In the process of the migration, the reticulum of dense ECM subtending the endothelium is degraded compromising the stability of the endothelium over the atherosclerotic plaque cap.Medicine, Faculty of
Pathology and Laboratory Medicine, Department of
Graduate
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Jahed, Mohammed Nazeem. "The application of differential pulse anodic stripping voltammetry for the determination of copper, lead, zinc and cadmium in airborne particulate matter". Thesis, [S.l. : s.n.], 1995. http://dk.cput.ac.za/cgi/viewcontent.cgi?article=1007&context=td_ptech.
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Vuong, Ngoc Quang. "Fingerprinting the effect of airborne particulate matter via in vitro toxicoproteomics". Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36939.
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It is a challenge to assess the toxicity of environmental air particulate matter (PM) because PM composition is complex and variable, due to source contribution and atmospheric transformation. The goal of this study is to establish an in vitro model that can fingerprint the cytotoxic effects of airborne PM and their associated toxicity mechanisms. For this purpose, the cytotoxic effects of different reference and environmental particles on A549 human lung epithelial cells were characterized using multiple endpoint assays (cytokine release, LDH release, BrdU incorporation, cellular ATP and resazurin reduction) and proteomic analyses (2D-GE and MALDI-TOF-TOF-MS/MS). The results of this study demonstrated that proteomic analyses can distinguish the influences of different (carbon black and titanium dioxide) and similar (cristobalite and α-quartz) particles on various pathways in A549 cells (e.g., cell death and cell proliferation); and the cytotoxicity assays were capable of differentiating the phenotypic outcomes of the particles, which were complementary and supportive to pathway analyses. The ability of in vitro toxicoproteomics to differentiate the toxicity of environmental particles was tested on Ottawa urban dust (EHC-93) and its water-insoluble and soluble fractions. Findings from both cytotoxicity assays and proteomic analyses consistently indicated that the insoluble materials explained most of the toxic effects of the total PM. Interestingly, the toxic potency of EHC-93 total was not equal to the sum of its insoluble and soluble fractions, implying inter-component interactions between insoluble and soluble materials that may be reflected through synergistic or antagonistic in vitro responses. The insoluble and soluble fractions uniquely altered the expression patterns of the proteins involved in pathways such as cell death, cell proliferation and inflammation. For example, the insoluble and soluble fractions oppositely altered the expression of the proteins (e.g., TREM1, PDIA3, PKM and ENO1) involved in an inflammatory response pathway in A549 cells, and the insoluble fraction was more potent than the soluble fraction in increasing secretion of pro-inflammatory cytokines MCP-1 and IL-8 from A549 cells. In essence, in vitro toxicoproteomics is a valuable tool in relating the physicochemical characteristics of ambient air particles to their biological reactivity through understanding their mechanisms of toxicity.
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Varadarajan, Charanya. "Explore the Link of PM10 with Meteorological Factors and Ambient Air Concentrations of Ozone, CO and NO2 using Time Series for Cleveland, Ohio". University of Toledo / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1083771115.
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Cobb, Charles Evan. "Spatial and temporal variations of PM2.5 mass and composition in Atlanta ASACA 1999-2006 /". Thesis, Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-11172006-161408/.
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Thesis (M. S.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2007.Dr. Armistead Russell, Committee Chair ; Dr. James Mulholland, Committee Member ; Dr. Michael Bergin, Committee Member.
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Varadarajan, Charanya. "Development of a Source-Meteorology-Receptor (SMR) Approach using Fine Particulate Intermittent Monitored Concentration Data for Urban Areas in Ohio". Connect to Online Resource-OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1197655960.
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Galvis, Remolina Boris. "Characterizing the emissions of fine particulate matter in the vicinity of a rail yard". Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/52927.
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Aerosol emissions from diesel combustion and other activities in rail yards can affect the health of urban populations. Fine particulate (PM[subscript 2.5]) concentrations near the Inman and Tilford rail yards in Atlanta, Georgia, are the highest measured in the state. The rail yard complex is surrounded by homes, schools, businesses and other industries. The impact of the aerosol emissions from these rail yards on local concentrations of PM[subscript 2.5] was quantified. Specifically, black carbon and PM[subscript 2.5] fuel-based emission factors from the rail yards were estimated by carbon balance using high time-resolution monitoring, a BC and PM[subscript 2.5] emissions inventory was estimated and dispersion modeling was applied to assess the impact of the rail yard activities on local air quality and the cost and benefits of upgrading locomotive engines with cleaner technologies was assessed. Further, baseline information that will allow a later evaluation of the improvement of local air quality as locomotives operating in the rail yards are upgraded was generated, and a composition profile of the rail yard aerosols was developed using chemical speciation techniques. These results found that activities from locomotives in the Inman and Tilford Rail yards lead to and an average emission factor of 6.0 ± 0.5 g of PM[subscript 2.5] per gallon of fuel and are responsible for increases in annual average concentrations of approximately 1.3 µg/m³ of PM[subscript 2.5] as far as 1 km from the perimeter of the rail yard complex. Approximately 11.7 tons of BC and 26 tons of PM[subscript 2.5] per year were emitted from the rail yards in 2011. The rail yards were found to be important sources of hydrocarbon-like organic aerosols (HOA) and black carbon from fuel (BCf). Upgrading the engines at the rail yards would decrease PM[subscript 2.5] emissions by about 9 t/year, reducing PM[subscript 2.5] concentrations around 0.5±0.1 µg/m³ as far as 1 km from the perimeter of the rail yard complex and producing monetized health benefits of approximately 24 million dollars per year.