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A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy. September 2016. / Numerous studies on the sources, transport and fates of criteria air pollutants and greenhouse gases have been done in southern Africa. However, debate on the priority pollutants and areas of concern continue despite a growing national air quality monitoring network. This study attempts a novel approach to characterise sources and ambient air quality over major industrial and urban areas using a single suite of instrumentation to provide information to improve management of air quality. Over 200 hours of data were collected from an airborne platform. Another 5 ground-based campaigns characterised sources and areas out of reach of the aircraft. The central aim of this study is to prioritise sources and areas of concern with regards to air quality management, using a mobile platform. This complements other modelling and spatial assessments and provides in situ validation for many contemporary debates. The specific aims were to characterise major anthropogenic sources; estimate the state of air quality; investigate the vertical distribution of pollutants; and prioritise sources and areas of concern for effective air quality management in South Africa. The research has delivered many original contributions to the body of knowledge of air quality over South Africa. These findings can be divided into spatial and temporal relationships between sources and receptors, characterising source contributions and understanding the contribution of atmospheric emissions. High resolution measurements show that spatial scales of prominent atmospheric plumes are much smaller than current remote sensing estimates.This underscores the difficulty of accurately assessing environments with diverse, clustered sources and complex meteorology through modelling studies and satellite based remote sensing. The current conceptual model of absolute stable layers is biased because of limited data availability where a limited number of levels are reported. At least 60 levels should be reported in soundings to study absolutely stable layers. The inclusion of the standard reporting levels, (850 hPa, 700 hPa, 500 hPa and 300 hPa), further biases the detection of atmospheric stable layers. The number of observed persistent levels change in number and character when these are omitted from the analysis. Numerous vertical profiles further show that the thermodynamic model of stability as the main driver of stratification is oversimplified, especially close to source regions where different pollutants are observed to peak at different levels unrelated to absolutely stable layers. This suggests that the original buoyancy which is governed by the release temperature, exit velocity and height are important drivers for the stratification of pollutants. The overall conclusion is made that a small team with a set of regular instrumentation can prioritise pollutants and areas of concern on a national scale. This method could be valuable for countries with limited resources and infrastructures and could be used in combination with modelling and satellite based remote sensing to assess priorities. The ability to obtain in situ data of a large number of variables over vast areas in a short time may offsets the caveats associated with mobile measurements and a limited sample volume. / LG2017

A thesis submitted to the Faculty of Geography, Archaeology, and Environmental Studies University of the Witwatersrand, Johannesburg, in fulfilment of the requirements of the degree of Doctor of Philosophy. 2015. / An imaging DOAS instrument, along with in situ trace-gas and aerosol instrumentation was deployed on board a research aircraft over the Highveld region of South Africa, to make regional-scale measurements of nitrogen dioxide (NO2). The presence of a “hotspot” of NO2 over the Highveld is confirmed. Case-study estimates of NO2 emission flux were made downwind of a power station (10 tons.hr−1), a petrochemical plant (36 tons.hr−1) and the entire Highveld region (395 tons.hr−1). Vertical profile measurements were used to develop scenarios for a radiative transfer sensitivity study. From this, suitable air-mass factors for the DOAS measurements were determined. Comparisons between the airborne DOAS and satellite instruments show a good agreement where the spatial scales of the satellite ground pixels and the features in the two-dimensional trace-gas distribution are matched. A long-term record of satellite data was analysed. Analysis of radiative transfer revealed a possible artefact in the adjacent positive and negative trends evident on the Highveld. A correction to the satellite record for a seasonal bias was made, and found to be important over biomass burning regions in Angola and Zambia. Spatial features in a seasonal model of the satellite record are shown to correspond with known urban, industrial and biomass burning sources in the region. Signatures of soil emissions are also detected.

"Elemental concentrations of airborne particulate matter at the Boulder Atmospheric Observatory have been analyzed as a function of height, time, particle size, anthropogenic activity, surface conditions, and various meteorological parameters. Aerosols were sampled at heights up to 49 meters during a one week period when the ground was at least partially covered with snow and the bottom 100 meters of the atmosphere was very stable"--Abstract. / Typescript. / "April, 1982." / "Submitted to the Department of Meteorology in partial fulfillment of the requirements for the degree of Master of Science." / Advisor: William H. Mach, Professor Directing Thesis. / Includes bibliographical references (leaves 117-121).

Descreve-se o método PIXE como uma técnica não destrutiva na análise quantitativa de traços de elementos em amostras de aerossol atmosférico. Fundamenta-se este método através do estudo da ionização de camadas internas de átonos por partículas carregadas e da secção de choque de produção de raios-X consequente do processo de ionização. A seguir são apresentados os conjuntos de impactadores em cascata utilizados pelo Grupo de Estudo de Poluição do Ar - IFUSP e pelo Grupo da FSU, na coleta de amostras de aerossol Atmosférico na cidade de Brasília, D.F.. São dadas. as características geométricas de cada conjunto e suas condições de funcionamento durante as amostragens. Discutem-se os resultados obtidos na análise PIXE das amostras provenientes dos dois conjuntos de impactadores procurando-se estabelecer correlações entre variações nas concentrações de mesmos elementos detectados nos dois conjuntos de impactadores. São discutidas possíveis causas que podem afetar o comportamento de dois conjuntos de impactadores e influir na análise de resultados obtidos pelo método PIXE. Para os casos em que há concordância nos resultados obtidos nas análises das amostras de aerossol atmosférico coletadas com impactadores em cascata e amostrador de filtro sequencial (apêndice 1) procura-se associar possíveis fontes de emissão de particulado na época das amostragens. Na complementação do método PIXE sugere-se a substituição do detector de Si (Li) por um espectrógrafo de cristal convexo. / The PIXE is described as a non destructive technique in the quantitative trace elimental analysis of aerossol atmospheric samples. The method is justified through the investigation of inner-shell ionization of atoms by charged particles and X-ray production cross section due the ionization process. Next are presented the sets of cascade impactors used during the aerossol sampling in Brasilia, Goiás, by the Group of Air Pollution Research - IFUSP and Air Chemistry Group - Oceanography Department - FSU. Dimensions of these two sets of impactors and conditions during the sampling are included in this work The results obtained from the analysis of the two sets of impactors are discussed correlating them with the variations in the amount of elements present in the samples. Possible causes changing the behavior of those impactors and can affect the analysis of results obtained by PIXE method are discussed. Results from impactors that are compatible with STREAKER analysis are interpreted according to possible emission sources of particulate matter in the atmosphere. In the implementation of PIXE apparatus the substitution of Si(Li) detector by a convex crystal X-ray spectrograph is suggested.

La thèse s’intéresse au rôle des pollutions industrielles sur les mécanismes de l’agglomération et de la croissance. Elle s’inscrit dans le corpus d’Economie Géographique et propose à la fois un travail de modélisation et une étude empirique. La localisation des activités industrielles polluantes représente un enjeu majeur pour les régions. Le gouvernement souhaite maintenir des activités économiques et une forte attractivité, tout en limitant les effets néfastes des dégradations environnementales issues des industries polluantes. En même temps, les pollutions industrielles affectent les autres secteurs et les ménages. Nous avons, tout d'abord, discuté les enjeux théoriques de la littérature concernant l’impact de l’agglomération sur la croissance et sur les émissions industrielles polluantes. Cela permet de mettre en évidence des limites des travaux de Nouvelle Economie Géographique et Croissance endogène (NEGG) sur la question, telle que la faible considération des dommages environnementaux. Ensuite, nous avons introduit une régulation environnementale dans un modèle de NEGG. Lorsque la taxe est différenciée entre les régions, elle a tendance à rendre l’équilibre de localisation plus dispersé. Enfin, nous montrons dans une étude empirique que les firmes des secteurs polluants bénéficient moins des économies d’agglomération. / The thesis focuses on the role of industrial emissions on economic mechanisms linking agglomeration and growth. This PhD thesis is settled in Economic Geography literature and display both theoretical and empirical studies. Location of polluting activities, mainly industrial ones, represents a sensitive issue for local governments. They want to maintain economic dynamism while preserving regional environmental capital. One needs to better understand the role of environmental issues in the arbitrage between growth and spatial equity. Indeed, industrial agglomeration impacts others sectors and household welfare through air pollution. Our review of literature shows that the effects of agglomeration on growth are well established. However, studies considering industrial pollution as a dispersion force are rare. We first build a model of NEGG with pollution regulation toward industrial firms. Then, an empirical study is conducted where we show that industrial firms benefit less from agglomeration economies.

Digitized by Kansas Correctional Industries

Digitized by Kansas Correctional Industries

Digitized by Kansas Correctional Industries

A wide range of synthetic chemicals and their metabolites present in the environment can antagonise the receptor activity of androgen hormones present in wildlife and humans. With increasing global production of new synthetic chemicals, little is known about their environmental fate, health consequences and end-points. This study was conducted to identify and characterise chemicals with anti-androgenic activity present in wastewater influent and effluent. This study was undertaken by applying a combination of biological and analytical chemistry techniques involving Solid Phase Extraction (SPE), High Performance Liquid Chromatography (HPLC) and an in vitro steroid receptor assay for profiling and characterising extracts of grab influent and effluent wastewater samples using a toxicity identification and evaluation (TIE) procedure. Initial work revealed variable recoveries of anti-androgenic activity from SPE of wastewaters. Therefore SPE methodology to screen wastewater samples was developed using a mixture of selected compounds which possess a range of polarities (log Kow). Their recoveries from SPE were measured by HPLC protocol and ranged from 95- 100%. The mean±SD and % RSD values of the analysed wastewater replicates were 3.20±0.03 mgFeq/L and 0.78% for influent and 0.22±0.01 mgFeq/L and 3.80% for effluent samples. The recoveries of wastewater extracts after fractionation were between 78.6% and 99.6%. Fractions containing anti-androgenic activity were analysed by Gas Chromatography Mass Spectrometry (GC-MS). A number of household chemicals were detected in both influent and effluent wastewater fractions that contained antiandrogenic activity. These included the anti-bacterial agents- triclosan, chlorophene, dichlorophene, chloroxylenol, the musk fragrance galaxolide, the flame retardantstris( 1-chloro-2-propyl)phosphate (TCPP) and tris(2-butoxyethyl)phosphate (TBEP), polymer plasticizer n-butylbenzenesulfonamide (NBBSA) and bisphenol A (BPA) which is a chemical associated with the polycarbonate usage. The anti-androgenic potency of pure contaminants compared with that of flutamide ranged from 0.04 (TCPP) to 13.40 (chlorophene). Anti-androgenic activity of 1.69 and 2.00% was recovered from the fractions of the effluent and influent samples respectively indicating that AA of about 98% are yet to be recovered. This work reveals for the first time that over 12 contaminants contribute to the total anti-androgenic activity present in wastewater effluent and that a number of compounds commonly used in household products (such as chlorophene, triclosan and NBBSA) are predominant anti-androgens in wastewater effluents.