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1
Speldewinde, Peter Christiaan. "Ecosystem health : the relationship between dryland salinity and human health". University of Western Australia. School of Population Health, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0127.
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Australia is experiencing widespread ecosystem degradation, including dryland salinity, erosion and vegetation loss. Approximately 1 million hectares (5.5%) of the south-west agricultural zone of Western Australia is affected by dryland salinity and is predicted to rise to 5.4 million hectares by 2050. Such degradation is associated with many environmental outcomes that may impact on human health, including a decrease in primary productivity, an increase in the number of invasive species, a decrease in the number of large trees, overall decrease in biodiversity, and an increase in dust production. The resulting degradation affects not only farm production but also farm values. This study examines the effects of such severe and widespread environmental degradation on the physical and mental health of residents. Western Australia has an extensive medical record database which links individual health records for all hospital admissions, cancer cases, births and deaths. For the 15 diseases examined in this project, the study area of the south west of Western Australia (excluding the capital city of Perth) contained 1,570,985 morbidity records and 27,627 mortality records for the 15 diseases examined in a population of approximately 460,000. Environmental data were obtained from the Western Australian Department of Agriculture?s soil and landscape mapping database. A spatial Bayesian framework was used to examine associations between these disease and environmental variables. The Bayesian model detected the confounding variables of socio-economic status and proportion of the population identified as Aboriginal or Torres Strait Islander. With the inclusion of these confounders in the model, associations were found between environmental degradation (including dryland salinity) and several diseases with known environmentally-mediated triggers, including asthma, ischaemic heart disease, suicide and depression. However, once records of individuals who had been diagnosed with coexistent depression were removed from the analysis, the effect of dryland salinity was no longer statistically detectable for asthma, ischaemic heart disease or suicide, although the effects of socio-economic status and size of the Aboriginal population remained. The spatial component of this study showed an association between land degradation and human health. These results indicated that such processes are driving the degree of psychological ill-health in these populations, although it remains uncertain whether this 4 is secondary to overall coexisting rural poverty or some other environmental mechanism. To further investigate this complex issue an instrument designed to measure mental health problems in rural communities was developed. Components of the survey included possible triggers for mental health, including environmental factors. The interview was administered in a pilot study through a telephone survey of a small number of farmers in South-Western Australia. Using logistic regression a significant association between the mental health of male farmers and dryland salinity was detected. However, the sample size of the survey was too small to detect any statistically significant associations between dryland salinity and the mental health of women. The results of this study indicate that dryland salinity, as with other examples of ecosystem degradation, is associated with an increased burden of human disease.
2
Zoannou, Kali-Stella. "Aspects of degradation of monoethanolamine solutions during Co2 absorption". Thesis, Cardiff University, 2011. http://orca.cf.ac.uk/18346/.
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The most common technique for carbon dioxide removal from gaseous streams is amine scrubbing, a proven technology in the oil and gas industries. The use of this route in coal fired power plants is not fully understood and the likelihood of solvent degradation is high. Decreased absorption efficiency, undesirable byproducts, the environmental impact of their disposal and increased process costs are the main consequences. In this study, two experimental rigs were designed and commissioned to explore the effects of gas composition and temperature on monoethanolamine degradation. Analytical procedures to detect and quantify its major thermal and oxidative degradation products were also developed. It became apparent early on that solvent degradation, under actual plant conditions, is a slow phenomenon, thus, it was decided to focus on thermal degradation. The present study uniquely enabled the absorption/desorption behaviour of thermally degraded solvents to be evaluated. The major thermal degradation products were quantified. After 14 full absorption/stripping cycles at the presence of 16% oxygen and 15% carbon dioxide, significant concentrations of nitrites and nitrates were detected in the samples. Thermal degradation at 160 oC for 8 weeks reduced monoethanolamine concentration by almost 95%, as evidenced by the chemical analysis, but the remaining solvent retained 22% of its capacity to remove carbon dioxide. Therefore, although not fully quantified, the requirement for monoethanolamine make-up may not be quite as serious as initially believed. There is some evidence to support that the rate of thermal degradation was enhanced as carbon dioxide loading increased and a 20% higher MEA loss was determined in the samples with the rich initial molar loading. A range of degradation products were quantified that correspond to those cited in the literature. 1-(2-hydroxyethyl)-2-imidazolidinone was indicated as the most stable MEA degradation product in the degraded samples at concentrations of up to 17% v/v.
3
Mingotti, Nicola. "Passive environmental design for health". Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.709015.
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Evanshen, Brian G., C. Knight, A. Zaslow, Phillip R. Scheuerman y G. R. Lanza. "In Situ Degradation of M-Cresol in Creosote Contaminated Soil". Digital Commons @ East Tennessee State University, 1992. https://dc.etsu.edu/etsu-works/2892.
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Gangula, Srilatha. "Degradation of Chlorophenols in Swine Waste". TopSCHOLAR®, 2010. http://digitalcommons.wku.edu/theses/151.
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Naturally occurring plant derived phenols can be degraded through bacteria in swine waste. Chlorinated phenols, which are not naturally present in the environment, are toxic and generated from industrial activities as such petrochemical, pharmaceutical, plastic, rubber, pesticide, iron, steel, paper production, coal conversion, wood preserving, and cellulose bleaching. Large scale coal gasification and carbonization plants are another source of chlorinated phenols. Although not normally present in the environment, chlorinated phenols are structurally similar to many plant derived phenolics.
It is our hypothesis that bacteria located in swine wastes may also have the ability to degrade chlorinated phenols. Identifying situations (and organisms) in which degradation of pollutants occurs is important field of research.
Experimental work was focused on measuring the degradation of seven chlorinated phenols in swine waste using solid-phase micro-extraction (SPME) and gas chromatography(GC). Microbes in the waste perform respiration or fermentation to obtain the energy they need to carry out their life processes. Fermentation is a process in which electrons are transferred from one organic substrate to another and which results in incomplete degradation of organic compounds. Anaerobic respiration is a process in which organic substrates are degraded completely to CO2, but using substances other than oxygen as the terminal electron acceptor (such as Fe(III), NO3- or SO42-). Anaerobic respiration using these alternative electron acceptors provides an easier pathway for degradation of aromatics than fermentation alone. Usually the abundance of these electron acceptors in waste is low since microbes consume them readily and thus they must be added to the mixture. Our work focused on development of methods for the quantification of chlorinated phenols in swine wastes and results of bioremediation research.
In this study, chlorophenols were extracted by SPME and analysed by GC. This research project mainly focused on the anaerobic degradation of chlorophenols in swine waste. It was observed that the decreased concentration of the chlorophenols was likely due to partitioning of the chlorophenols to solids, sticking to glass bottles and by bacteria present in the swine waste.
In summary, it was observed that by ANOVA and gas production analysis 2,6-dichlorophenol and 2,4,5-trichlorophenol were likely to be degraded by bacteria present in swine waste.
6
Howell, Desiree Pearl. "Evaluation of surfactants for the enhancement of PCB degradation". Thesis, Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/20746.
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Barrett, E. y Phillip R. Scheuerman. "The Effect of Cell Inoculum Level and Substrate Concentration on p- cresol Degradation". Digital Commons @ East Tennessee State University, 1998. https://dc.etsu.edu/etsu-works/2914.
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Otter, Robert. "Aspects of environmental public health in Portsmouth, 1764-1864". Thesis, University of Portsmouth, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387284.
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Black, T. E., Phillip R. Scheuerman y G. R. Lanza. "Effects of Initial Biomass Concentration on the Degradation of the Creosote Constituent m-Cresol". Digital Commons @ East Tennessee State University, 1995. https://dc.etsu.edu/etsu-works/2902.
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Fitzwater, Kendra K. "Assessment of environmental and public health hazards of electronic waste". Virtual Press, 2007. http://liblink.bsu.edu/uhtbin/catkey/1380100.
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Electronic waste or `e-waste' is a rapidly growing form of solid waste worldwide. The heavy metals present in various electronic components demand attention because such metals may leach and pose significant health and environmental hazards (U.S. EPA, 2007). Knowledge of the potential of heavy metal leaching from e-waste represents an important contribution for developing U.S. standards for classifying e-waste as hazardous waste. Hazardous elements which leach from a variety of electronics wastes were assessed in laboratory batch studies. Electronic components evaluated included PC cathode ray tubes, PC motherboards, PC mice, television remote controls, and cellular phones. Each component was disassembled and digested using the Toxicity Characteristic Leaching Procedure (TCLP), EPA Method 1312, Method EA NEN 7371 (Dutch Environmental Agency), and Method DEV-S4 (Germany). The extracts were analyzed for lead, cadmium, chromium, silver, and cobalt. The TCLP consistently leached the greatest amounts of all metals; TCLP-soluble lead was extracted well beyond federal limits for several electronic devices.Department of Natural Resources and Environmental Management
11
Brimecombe, Rory Dennis. "Voltammetric analysis of pesticides and their degradation". Thesis, Rhodes University, 2006. http://hdl.handle.net/10962/d1015724.
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Amitraz is a formamide acaricide used predominantly in the control of ectoparasites in livestock and honeybees. Amitraz hydrolysis is rapid and occurs under acidic conditions, exposure to sunlight and biodegradation by microorganisms. The main hydrolysis product of amitraz, 2,4-dimethylaniline, is recalcitrant in the environment and toxic to humans. An electrochemical method for the determination of total amitraz residues and its final breakdown product, 2,4-dimethylaniline, in spent cattle dip, is presented. Cyclic voltammetry at a glassy carbon electrode showed the irreversible oxidation of amitraz and 2,4-dimethylaniline. A limit of detection in the range of 8.5 x 10⁻⁸ M for amitraz and 2 x 10⁻⁸ M for 2,4-dimethylaniline was determined using differential pulse voltammetry. Feasibility studies in which the effect of supporting electrolyte type and pH had on electroanalysis of amitraz and its degradants, showed that pH affects current response as well as the potential at which amitraz and its degradants are oxidised. Britton-Robinson buffer was found to be the most suitable supporting electrolyte for detection of amitraz and its degradants in terms of sensitivity and reproducibility. Studies performed using environmental samples showed that the sensitivity and reproducibility of amitraz and 2,4-dimethylaniline analyses in spent cattle dip were comparable to analyses of amitraz and 2,4-dimethylaniline performed in Britton-Robinson buffer. In addition, the feasibility qf measuring amitraz and 2,4-dimethylaniline in environmental samples was assessed and compared to amitraz and 2,4-dimethylaniline analyses in Britton-Robinson buffer. Amitraz and 2,4-dimethylaniline were readily detectable in milk and honey. Furthermore, it was elucidated that 2,4-dimethylaniline can be metabolised to 3-methylcatechol by Pseudomonas species and the proposed breakdown pathway is presented. The biological degradation of amitraz and subsequent formation of 2,4-dimethylaniline was readily monitored in spent cattle dip. The breakdown of amitraz to 2,4-dimethylaniline and then to 3-MC was monitored using cyclic voltammetry.
12
Haddock, Janet Elain. "Marine life degradation in Hong Kong : an evaluation of possible causes and mitigating strategies /". Thesis, Hong Kong : University of Hong Kong, 1995. http://sunzi.lib.hku.hk/hkuto/record.jsp?B14709314.
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Barrett, E. y Phillip R. Scheuerman. "Effect of Inoculum level of a Freeze-Dried Consortium and Substrate Concentration on p-cresol Degradation". Digital Commons @ East Tennessee State University, 1998. https://dc.etsu.edu/etsu-works/2915.
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Wolfe, V., Phillip R. Scheuerman, M. Gallagher y G. R. Lanza. "Effects of Nitrogen, Phosphorus, and a Vitamin Mixture on Degradation rates of cresol isomers". Digital Commons @ East Tennessee State University, 1995. https://dc.etsu.edu/etsu-works/2903.
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Hedberg, Yolanda. "Environmental and health aspects of corrosion– importance of chemical speciation". Licentiate thesis, KTH, Yt- och korrosionsvetenskap, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-24701.
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During the last decades, the interest in corrosion of metals and alloys from an environmental and health perspective has increased rapidly as a consequence of stricter environmental and human exposure legislations, their extensive use as implant materials and an increasing understanding related to occupational and/or daily exposure to airborne particles. Corrosion-induced metal release, however, needs to be understood in detail and to include knowledge related to chemical speciation, i.e. the oxidation state, complexation and chemical form of released metals, parameters of high importance when considering toxicity. In this licentiate work, corrosion-induced metal runoff from roofing materials (copper, zinc, and chromium(III)-, and chromium(VI) surface treated galvanized steel) has been investigated from an environmental perspective with focus on chemical speciation of released metals (Papers I-II). From these papers it was evident that the total concentration measured in the runoff water is not sufficient for any environmental risk assessment. The environmental fate including changes in chemical speciation and hence metal precipitation has to be considered. For example, it was shown that the copper concentration decreased by three orders of magnitude already in the internal drainage system of a shopping centre with a copper roof, to a concentration lower than storm water collected from a nearby parking space (Paper I). Also, speciation measurements can explain corrosion, metal release and surface processes of chromium surface treated galvanized steel at different sites (urban and marine). Any environmental risk assessment has to be done by considering all metal species released, and compared with ecotoxic values. For example, when most chromium(VI) (the most toxic species) was released, significantly less zinc was released at the same time which decreased the overall ecotoxicity of the runoff water significantly (Paper II). When assessing environmental risks by standard laboratory tests, it is important to understand all mechanisms which are possibly influenced by individual experimental parameters and which often are different for different test substances. Some metals released, as seen in the case of iron, may precipitate with time and be pH-, solution- and buffering dependent. This behavior can lead to strongly underestimated measured metal concentrations (Paper III). When particles of metals or alloys are to be investigated (Papers III-VI), it is essential to conduct a thorough particle characterization, since the surface properties cannot be defined. In addition, the surface properties (oxide layer properties) change with varying particle size (Paper VI) and with other experimental parameters such as dispersion (Paper VI). All iron-, and chromium-based particles investigated (Papers III-VI) revealed large differences between alloy particles and pure metals. Particles of pure iron and nickel released significantly more metals compared with particles of the investigated alloys, whereas particles of pure chromium released less metals compared with the alloys. Particles of stainless steel (AISI 316L), ferro-chromium and ferro-silicon-chromium released very low amounts of metals (Papers III-VI). The released quantity increased with increased acidity (Papers III-VI) and also in the presence of complexing agents (ongoing research). The manufacturing process is of high importance, as observed for stainless steel particles when compared with a side product from stainless steel production with similar composition that released significantly more metals (Paper III). Particles of metal oxides, i.e. chromium(III)oxide and iron(II,III)oxide, released very low amounts of metals due to their thermodynamic stability. Ongoing research activities focus on the specific influence of complexing agents and proteins on the metal release process from massive sheet and particles of metals and alloys. The applicability and the possibility to use different analytical tools are investigated and elaborated for small-sized particles. A detailed understanding of the correlation between material and particle characteristics, the metal release process, the chemical speciation in interaction with proteins and/or cells, and the particle/cell interaction is essential to enable any correlation between material/particle characteristics and toxicity. The aim of this licentiate summary is – in contrast to the six included scientific papers – to explain the importance of chemical speciation for corrosion processes from a health and environmental perspective in a popular way to reach a broad non-academic audience. The summary is hence written as a guidance document for stakeholders and the regulatory community working with environmental and health risk assessment.QC 20101006
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Ziegler, B., Phillip R. Scheuerman y G. R. Lanza. "Degradation Rates of M-Cresol Using Immobilized and Free Microbial Assembages". Digital Commons @ East Tennessee State University, 1993. https://dc.etsu.edu/etsu-works/2894.
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Vladimirova, Ekaterina. "Values for sustainable future: transforming values in the context of climate change and global environmental degradation". Doctoral thesis, Universite Libre de Bruxelles, 2014. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/241295.
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Smith, Kiara L. "Anaerobic Degradation of Polycyclic Aromatic Hydrocarbons at a Creosote-Contaminated Superfund Site and the Significance of Increased Methane Production in an Organophilic Clay Sediment Cap". PDXScholar, 2010. https://pdxscholar.library.pdx.edu/open_access_etds/101.
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The overall goal of this work was to investigate microbial activity leading to the anaerobic degradation of polycyclic aromatic hydrocarbons and an organophilic clay sediment cap used at a creosote-contaminated Superfund site. To determine whether or not PAHs were being degraded under anaerobic conditions in situ, groundwater and sediment porewater samples were analyzed for metabolic biomarkers, or metabolites, formed in the anaerobic degradation of naphthalene (a low-molecular weight PAH). In addition, a groundwater push-pull method was developed to evaluate whether the transformation of deuterated naphthalene to a deuterated metabolite could be monitored in situ and if conservative rates of transformation can be defined using this method. Metabolites of anaerobic naphthalene degradation were detected in all samples that also contained significant levels of naphthalene. Anaerobic degradation of naphthalene appears to be widespread in the upland contaminated aquifer, as well as within the adjacent river sediments. A zero-order rate of transformation of naphthalene-D₈ to naphthoic acid-D₇was calculated as 31 nM·d-¹. This study is the first reported use of deuterated naphthalene to provide both conclusive evidence of the in situ production of breakdown metabolites and an in situ rate of transformation. Methane ebullition was observed in areas of the sediment cap footprint associated with organophilic clay that was used a reactive capping material to sequester mobile non-aqueous phase liquid (NAPL) at the site. Anaerobic slurry incubations were constructed using sediment core samples to quantify the contribution of the native sediment and the different layers of capping material (sand and organophilic clay) to the overall methane production. Substrate addition experiments using fresh, unused organophilic clay, as well as measured changes in total carbon in organophilic clay over time supported the hypothesis that microbes can use organophilic clay as a carbon source. Quantitative PCR (qPCR) directed at the mcrA gene enumerated methanogens in field samples and incubations of native sediment and capping materials. Denaturing gradient gel electrophoresis (DGGE) was also performed on DNA extracted from these samples to identify some of the predominant microorganisms within the sediment cap footprint. The organophilic clay incubations produced up to 1500 times more methane than the native sediment and sand cap incubations. The organophilic clay field sample contained the greatest number of methanogens and the native sediment contained the least. However, the native sediment incubations had greater numbers of methanogens compared to their respective field sample and comparable numbers to the organophilic clay incubation. An increase in methane production was observed with the addition of fresh, unused organophilic clay to the already active organophilic clay incubations indicating that organophilic clay stimulates methanogenesis. In addition, organophilic clay retrieved from the field lost about 10% of its total carbon over a 300-day incubation period suggesting that some component of organophilic clay may be converted to methane. DGGE results revealed that some of the predominant groups within the native sediment and sediment cap were Bacteriodetes, Firmicutes, Chloroflexi, and Deltaproteobacteria. An organism 98% similar to Syntrophus sp. was identified in the organophilic clay suggesting this organism may be working in concert with methanogens to convert the organic component of organophilic clay ultimately to methane. The capacity of organophilic clay to sequester organic contaminants will likely change over time as the organic component is removed from the clay. This, in turn, affects the use of this material as a long-term remedial strategy in reduced, contaminated environments.
19
Loyd, Chapman Kemper. "Anaerobic/aerobic degradation of a textile dye wastewater". Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-08042009-040351/.
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Garcia, Hernandez Jacqueline. "Aspects of ecosystem health in the Colorado River Delta, Mexico". Diss., The University of Arizona, 2001. http://hdl.handle.net/10150/279931.
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Two aspects of ecosystem health in the Colorado River delta were investigated as part of the present dissertation. The following is a summary of the most important findings: Contaminants of natural origin (e.g. selenium) and anthropogenic activities (e.g. pesticides) represent a potential threat for humans and wildlife in the Colorado River delta. Fourteen locations were sampled for bottom material and biota from March 1998 to April 2000. Concentrations of selenium in bottom material ranged from 0.6-5.0 μg/g. Concentrations of selenium in biota ranged from 0.5-18.3 μg/g, 23% of these samples exceeded the toxic threshold where reproductive impairment in birds from dietary exposure is reported. Concentrations of DDE exceeded the lower critical dietary level for sensitive species in 30% of biota samples. No clear relationship could be found between the concentration of Se in bottom material and the concentration of Se in fish. Nevertheless, smaller Se concentrations in biota were found at sites that had an outflow and exposure or physical disturbance of the bottom material was uncommon. Greater concentrations of Se in biota were found at sites with strongly reducing conditions, no output, and subsequent periods of drying and flooding or dredging activities, and at sites that received water directly from the Colorado River. The southwestern willow flycatcher (Empidonax traillii extimus ) is an endangered neotropical migrant with only 300-500 breeding pairs. The objective of the second study was to determine the presence/absence of this bird in the Colorado River delta. Surveys were conducted from June to July, 1999 and from May to June, 2000 using an audio tape of this subspecies' songs to elicit responses. We detected a total of 50 willow flycatchers in the Colorado River delta in the months of May to June. None were detected in July, thus, the birds were most likely migrants. Restoration of the intensively used stopover sites of the Colorado River delta appears to be essential for the overall recovery of this subspecies. Additionally, we propose a possible willow flycatcher summer migratory route throughout the series of coastal estuaries found adjacent to the coast of Sonora.
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Shearer, Megan Marie. "Tibetan Buddhism and the environment: A case study of environmental sensitivity among Tibetan environmental professionals in Dharamsala, India". CSUSB ScholarWorks, 2005. https://scholarworks.lib.csusb.edu/etd-project/2904.
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The purpose of this study was to investigate environmental sensitivity among environmental professionals in a culture that is assumed to hold an ecocentric perspective. Nine Tibetan Buddhist environmental professionals were surveyed in this study. Based on an Environmental Sensitivity Profile Insytrument, an environmental sensitivity profile for a Tibetan Buddhist environmental professional was created from the participants demographic and interview data. The most frequently defined vaqriables were environmental destruction/development, education and role models.
22
Salkic, Sabina. "Monitoring Photocatalytic Degradation of X-ray Contrast Media with Raman Spectroscopy". TopSCHOLAR®, 2012. http://digitalcommons.wku.edu/theses/1167.
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X-ray contrast media such as diatrizoate and iohexol have been found in wastewater and drinking water and are difficult to remove because they are resistant to water treatment processes. A removal process can be started with ultraviolet photocatalytic degradation of X-ray contrast media in the presence of titanium dioxide or other catalysts. Raman spectra of diatrizoate and iohexol were taken in an aqueous solution in the presence and absence of titanium dioxide during exposure to ultraviolet radiation. Raman intensity is directly proportional to concentration; therefore, we can measure the rate of the reaction based on changes in the Raman spectrum. Changes were monitored for eight hours. Evidence of photoreaction is observed, indicating that the degradation of X-ray contrast media can be measured using Raman spectra. To our knowledge, this represents the first use of Raman spectroscopy to monitor photocatalytic degradation in real time, opening a potentially powerful approach to studying the removal of pollutants in the environment.
23
Walls, A. y Phillip R. Scheuerman. "The Effects of Substrate Concentration and Cell Density on the Rate of Degradation of o-cresol Using a Freeze-Dried Consortium". Digital Commons @ East Tennessee State University, 1998. https://dc.etsu.edu/etsu-works/2917.
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Ruan, Ruoling y 阮若琳. "Environmental noise and non-auditory health impacts in Hong Kong". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/206958.
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The magnitude of noise pollution is fast-growing worldwide. Environmental noise has been linked with several non-auditory health impacts, including annoyance, sleep disturbance, cardiovascular diseases and impaired cognitive performance. Also, environmental noise exposure is associated with increased reported psychological symptoms, prolonged healing time of patients and poorer performance of staff in hospitals. Hong Kong has been suffering from environmental noise for years, especially transportation noise, but lack of relevant local studies to support public health intervention. This review is attempted to summarize three governmental study reports and overseas studies on the relationship between noise and non-auditory effects. Also data on noise complaints will be briefly analysed as a supplement. It is ascertained that noise pollution and noise-induced annoyance and sleep disturbance are prevalent in Hong Kong. Also, noise mapping and subjective auditory effect scales are already available. Noise complaint level in Hong Kong is generally lower than levels in London and New York City, but is probably underestimated. Future studies are needed to emphasize on noise exposure in particular areas and vulnerable populationspublished_or_final_version
Public Health
Master
Master of Public Health
25
Woo, Chunho Anthony y 鄔俊豪. "Molecular ecology and public health risks of urban bio-aerosols". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hub.hku.hk/bib/B49617680.
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The Earth’s atmosphere supports microorganisms and they include potential pathogens and microbial allergens. Whilst indoor environments have been well studied, relatively little is known of bio-aerosols in outdoor locations and their potential influence on human health, particularly with regard to urban development. Hong Kong provides an ideal model system for testing hypotheses related to the impact of urbanization on bio-aerosols, with a well-defined gradient of urbanization and large population. This thesis describes work to establish the biodiversity and spatio-temporal dynamics of outdoor bio-aerosols in Hong Kong. A comprehensive study of multi-domain microbial diversity and allergen levels in urban aerosols over a contiguous annual timescale and along a gradient of urbanization was carried out. A comprehensive suite of climatic and pollutant variables were also recorded during the sampling interval. Terminal restriction fragment length polymorphism (T-RFLP) was employed to investigate variations in bacterial and eukaryal assemblages, followed by phylogenetic assessment using high-throughput sequencing. The results revealed a strong seasonality in both bacterial and eukaryal assemblages, with Archaea forming a negligible part of the urban bio-aerosols. The most abundant bacteria were proteobacteria but community shifts were seen due to increases in algae in summer, and betaproteobacteria and cyanobacteria in winter. This was most parsimoniously explained by considering the backward trajectory analysis of air mass. A greater abundance of marine-associated phylotypes such as Bacillariophyta and Chlorophyta were identified when the dominant air mass arriving in Hong Kong in the summer originated from oceanic sources. In contrast, betaproteobacteria, which indicated soil sources were prevalent when the origin of air mass was from terrestrial sources. A trend in fungal phylotypes was also apparent, with summer samples dominated by basidiomycetous Agaricales, and winter samples by the ascomycete genus Cladosporium. This was likely due to favourable climatic conditions during wetter summer months enhancing release of fungal basidiospores. A range of airborne human pathogens was also detectable at low levels including pathogenic bacteria such as Acinetobacter baumannii, Clostridium perfringens, Escherichia coli O157:H7, and Ricinus communis, and the pathogenic fungus Aspergillus terreus. Microbial allergens including bacterial endotoxins and fungal glucans were also quantified with immunological assays. These generally followed variations in biomass, and during some months were recorded at levels that may impact human health upon chronic exposure. Carbon dioxide levels were the only climatic or pollutant variable that correlated with allergen levels. Conversely changes in microbial assemblages were strongly correlated to several climatic variables including temperature, rainfall, air pressure and relative humidity, but not with the degree of urbanization or airborne pollutants. This study highlights the importance of including microbial assessments in future bio-surveillance of urban aerosols.published_or_final_version
Biological Sciences
Doctoral
Doctor of Philosophy
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Smet, Michiel. "Rangeland degradation around water-points under different management systems". Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/50074.
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Thesis (MScConEcol )--University of Stellenbosch, 2004.ENGLISH ABSTRACT: Over 70% of South Africa is too arid for crop farming and is used for commercial livestock ranching, communal livestock ranching, or game ranching. These management systems differ from each other in a number of aspects, e.g. herbivore species, stocking rate, grazing regime, and management structure. The main question addressed in this study is: to what extent do the three management systems affect rangeland condition? Following the equilibrium paradigm of vegetation dynamics, communal livestock ranches are expected to have a greater detrimental effect on rangeland condition than other management systems because stocking densities and, consequently, herbivore impacts, are usually far higher than under the other two management systems. However, recent nonequilibrium theories argue that vegetation dynamics in arid systems are mainly driven by rare and stochastic rainfall events. Biotic factors, such as grazing and herbivore diversity, are predicted to have little effect on rangeland condition. This leads to the prediction that herbivore impacts on arid ecosystems are not density-dependent and, consequently, the high stocking densities commonly recorded on communal livestock ranches will not cause more rangeland degradation than other management systems. Arid and semi-arid rangelands are characterised by high inherent spatial and temporal variation in vegetation and soil parameters. Hence, differentiating between the effects of grazing management systems and natural variability caused by abiotic factors, such as rainfall, is difficult. This problem can be circumvented by examining gradients of grazing intensity radiating from water-points (= piospheres). I examined changes in vegetation and soil parameters along 500 m-Iong grazing gradients on ranches in the semi-arid Northem Cape province, South Africa, with the three abovementioned management systems. Analysis of the vegetation on these ranches demonstrated the existence of grazing gradients around the water-points. Two characteristic zones described in other studies were identified, namely the sacrifice zone (almost complete denudation of the vegetation close to the water-point) and the dense shrub zone (distal to the sacrifice zone). Communal livestock ranching had a greater negative effect on rangeland vegetation than the two other ranching systems, particularly with regard to annual grass species diversity, percentage of bare soil, and shrub density. Within 100 m of the water-points, soil quality was negatively affected by commercial cattle ranching. Contrastingly, there were no significant effects of the other two management systems on soil quality in the piosphere. The feeding of supplemental forage and nutrients may explain the greater impact of commercial cattle farming on soil quality. The results of this study are consistent with the predictions of the equilibrium theory of vegetation dynamics because grazing impacts were density-dependent in these semi-arid rangelands. However, the results presented here also indicate that forage supplementation alters the spatial and temporal distribution of livestock in a manner that may have greater negative impacts on soil quality than density of livestock per se.
AFRIKAANSE OPSOMMING: Meer as 70% van Suid-Afrika is te droog vir gewasverbouing en word gebruik vir kommersiële veeboerdery, gemeenskaplike veeboerdery of wildboerdery. Die bestuur van dié verskillende boerderytipes verskil wesentlik van mekaar in verskeie opsigte, ondermeer herbivoorspesies, veeaanskaffingstempo, weidingstipe en bestuurstruktuur. Die belangrikste vraag wat aangespreek word in die studie is die volgende: Tot watter mate affekteer die drie verskillende boerderybestuurstipes die toestand van weivelde? Gesien teen die agtergrond van die ekwilibriumparadigma van plantedinamika, word verwag dat gemeenskaplike veeboerdery 'n groter impak op die toestand van weiveld sal hê as ander boerderytipes, omdat veedigtheid en gevolglik herbivoor-impak gewoonlik veel hoër is as met die ander twee boerderytipes. Onlangse nie-ekwilibria-teorië voer egter aan dat plantedinamika in ariede gebiede gedryf word deur seldsame en buitengewone reënvalgebeure. Biotiese faktore, soos weiding en herbivoor diversiteit sal na verwagting min effek hê op die toestand van weiveld. Hieruit volg die voorspelling dat herbivoorimpak op ariede ekosisteme nie afhanklik is van digtheid nie, en dat hoë veedigtheid algemeen aangeteken vir gemeenskaplike boerderye, nie rede sal wees vir groter ver1iese in weiveld nie. Ariede en semi-ariede weivelde word gekenmerk deur 'n hoë ruimtelike en tydelike veranderinge in plant- en grondparameters. Gevolglik is dit moeilik om te onderskei tussen die effekte van weidingsbestuur en natuur1ike veranderings wat veroorsaak word deur nie-biotiese faktore, soos reënval. Dié probleem kan oorbrug word deur gradiënte van weidingsintensiteit, wat vanaf waterpunte uitstraal, te ondersoek. Vervolgens het ek binne al drie bg. boerderybestuursisteme veranderinge in plant- en grondparameters langs SOOm-lange weidingsgradiënte ondersoek op plase in die semiariede Noord-Kaap provinsie van Suid-Afrika. Plantegroei-analise het getoon dat 'n weidingsgradiënt rondom waterpunte voorkom. Twee kenmerkende sones is in ander studies geïdentifiseer, nl., 'n opofferingsone (waar amper alle plantegroei naby waterpunte uitgetrap is) en die digte, struik-sone (distaal to die opofferingsone). Gemeenskapsveeboerdery het 'n groter negatiewe effek op plaasgewasse as die ander twee boerderytipes, veral waar dit betrekking het op grasspesie-diversiteit, persentasie grond sonder plantbedekking en struikdigtheid. Binne 100m vanaf waterpunte, is grondkwaliteit merkbaar negatief geaffekteer deur kommersiële veeboerdery. Daarteenoor, was daar geen merkbare effek op die grondkwaliteit naby waterpunte van die ander twee boerderytipes nie. Aanvullingsvoer kan moontlik die rede wees vir die waargenome, groter impak van kommersiële veeboerdery op grondkwaliteit. Die resultate van die studie strook met voorspellings van die ekwilibria-teorie van plante-dinamika, daarin dat weidingsimpak digtheidsafhanklik is in hierdie semiariede plaasgebiede. Die resultate toon ook egter, dat voedingsaanvullings die ruimtelike en tydelike verspreiding van vee in so 'n wyse verander, dat dit moontlik 'n veel groter negatiewe uitwerking op grondkwaliteit het as veedighteid per se.
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杜家榮 y Ka-wing To. "Environmental, cost and health benefits of district cooling". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B4257657X.
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Wei, Xi. "Environmental screening of endocrine-disrupting chemicals and biological characterization of their effects on reproductive health". HKBU Institutional Repository, 2011. http://repository.hkbu.edu.hk/etd_ra/1225.
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Pelham, Todd B. "DEGRADATION OF PROTECTIVE GLOVE MATERIALS EXPOSED TO COMMERCIAL PRODUCTS: A COMPARATIVE STUDY OF TENSILE STRENGTH AND GRAVIMETRIC ANALYSES". CSUSB ScholarWorks, 2014. https://scholarworks.lib.csusb.edu/etd/107.
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ABSTRACT
Current glove guides attempt to assist in recommending which type of glove is appropriate for handling chemicals; however, they include information on less than 1% of the 89 million chemical products available today.
This study offers a solution by testing five durable polymer materials against 50 chemicals, using two rapid chemical degradation assessment techniques. The first technique involves gravimetric analysis of the weight change following constant immersion against the chemical mixture. The second method uses tensile strength to assess molecular changes in the polymer structure.
This study is focused on addressing three issues of concern. First, this study examines if current degradation testing methods are adequate to determine chemical resistance against complex mixtures. Secondly, this study will be used to determine if current degradation information on pure chemicals is effective in predicting degradation of complex chemical mixtures, based on the major ingredient(s). Lastly, this study will start a chemical resistance index for complex mixed chemicals.
The results of this study clearly show that glove recommendations of pure and mixed chemicals are frequently different. In more than 58.4% of the cases, the mixed chemical requires a different glove than that of its pure chemical components. Results also show that glove recommendations based solely on weight change and/or permeation results are missing important information on tensile test performance. There are several instances (15.2%) in which the initial glove recommendation would be changed to a lower recommendation rating if the results of a tensile test were included.
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Huang, Kai Katie y 黄恺. "The effects of walkability on air pollution and public health". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46937213.
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Cheema, Mahmood A. (Mahmood Ahmad). "Environmental health, risk analysis and safety aspects of nuclear magnetic resonance and spectroscopy systems". Thesis, Massachusetts Institute of Technology, 1991. https://hdl.handle.net/1721.1/129503.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Nuclear Engineering, 1991.Title as it appears in the June, 1991 M.I.T. Graduate List: Geochemistry and petrogenesis of basalts from Broken Ridge and Naturaliste Plateau, S.E. Indian Ocean.
Includes bibliographical references (leaves 47-48).
by Mahmood A. Cheema.
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Nuclear Engineering, 1991.
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Xulu, Sifiso. "Land degradation and settlement intensification in Umhlathuze Municipality". Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86208.
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Thesis (MSc)--Stellenbosch University, 2014.ENGLISH ABSTRACT: The multifaceted land degradation problem and its associated manifold impacts have attracted research from different disciplines, resulting in varying definitions of the concept. However, most researchers agree that human intervention that deteriorates the state of the environment is the central element. Among the anthropogenic activities that exacerbate land degradation, land cover has been singled out as the salient element. Rapid and unplanned land cover changes are primary manifestations of this problem. UMhlathuze Municipality, the study area which has superior biodiversity richness, is one of fastest growing municipalities in South Africa and is the locale of significant land modifications in recent decades because of a variety of industrial and residential developments. Using Landsat TM imagery acquired for 1984, 1996 and 2004, this study mapped and quantified land cover change and manifestations of land degradation in the uMhlathuze Municipality in conjunction with settlement intensification computed from orthophotographs acquired for 1984 and 2004. Census population statistics were analysed as a reflection of population dynamics and further to gauge related causes of land cover change. Geographical information technology (GIT) was applied as an analytical tool. The results revealed the anthropogenic influences that led to changes in land cover over the 20- year period between 1984 and 2004. The dominant natural cover classes in 1984 declined continuously and human-dominated land categories had increased sharply by 2004. Much of grasslands, forest and wetlands were converted to monotypical agroforestry (sugar cane and forestry plantations), built-up settlement and mining. These changes engendered complete loss of biodiversity (floral and migration of fauna). Bare ground, signifying land degradation, was noticeable although it exhibited a fluctuating trend which could be attributable to differences between the various imagery used. Along with population growth, the area of settlements increased over the study period and spatially sprawled from urban areas. Settlements showed a fairly stable spatial configuration over the 20-year period, but became magnified in medium- and high-density areas. Grassland and wetlands occurring around Richards Bay, as well as indigenous forest near Port Durnford, were identified as critically threatened ecosystems. The proposed industrial development zone and port expansion were recognized as having adverse ecological implications for wetlands. The study concluded that significant land cover changes occurred in the form of natural land cover giving way to monotypical agroforestry, built-up settlements and mining - all to the detriment of pristine natural habitat.
AFRIKAANSE OPSOMMING: Die veelvlakkige probleem van omgewingsdegradasie en die gepaardgaande veelsoortige impakte lok navorsing uit verskillende dissiplines, wat lei tot verskillende definisies van die konsep. Tog is die meeste navorsers dit eens dat menslike invloede die sentrale element is wat die toestand van die omgewing verswak. Van die vele menslike aktiwiteite is grondgebruikverandering uitgesonder as die belangrikste beïnvloeder van agteruitgang van die omgewing. Veral vinnige en onbeplande grondgebruikveranderinge verteenwoordig die primêre manifestasies van hierdie probleem. UMhlathuze Munisipaliteit, die studiegebied met 'n hoë biodiversiteitsrykdom, is een van die vinnigste groeiende munisipaliteite in Suid-Afrika, waar 'n verskeidenheid nywerheids- en residensiële ontwikkelings beduidende grondgebruikverandering oor die afgelope dekades dryf. Met behulp van Landsat TM beelde van 1984, 1996 en 2004, is hierdie studiegebied gekarteer en oppervlaktes gekwantifiseer om grondgebruikverandering en verwante manifestasies van die agteruitgang van landbedekking in die uMhlathuze Munisipaliteit te konstateer. Tesame hiermee is die verdigting van nedersettings ook met behulp van ortofoto’s van 1984 en 2004 aangeteken. Bevolkingsensusstatistieke is ontleed as weerspieëling van die gepaardgaande bevolkingsdinamika en om moontlike oorsake van verandering in grondbedekking te bepaal. Vir hierdie doel is geografiese inligtingstegnologie (GIT ) as analitiese instrument toegepas. Die resultate toon antropogeniese invloede lei tot veranderinge in grondbedekking oor die tydperk van 20 jaar tussen 1984 en 2004. Die dominante natuurlike dekkingsklasse in 1984 het voortdurend verminder en menslik-gedomineerde kategorieë het teen 2004 skerp gestyg. Baie van die grasvelde, woude en vleilande is daadwerklik omskep tot monotipiese agro-bosbou (suikerrieten bosbouplantasies), beboude nedersetting en mynbou. Hierdie veranderinge behels 'n volledige verlies van biodiversiteit (plantegroei en migrasie van fauna). Kaalgrond, wat dui op die agteruitgang van grondbedekking, was ook opvallend, hoewel dit 'n wisselende tendens toon wat ook kan wees as gevolg van die verskille tussen die beeldmateriaal wat gebruik is. Saam met die groei van die bevolking is bevind dat nedersettings oor die studieperiode toegeneem het en in tipiese spreipatrone weg van die stedelike gebiede uitbrei. Nedersettings het 'n redelik stabiele ruimtelike liggingsopset oor die tydperk van 20 jaar getoon, maar het in medium- en hoë- digtheid gebiedeverdeel. Die voorkoms van grasveld en vleiland rondom Richardsbaai, asook inheemse woud naby Port Durnford, is geïdentifiseer as krities-bedreigde ekosisteme. Die voorgestelde nywerheidsontwikkelingsone en hawe-uitbreiding is geïdentifiseer as ontwikkelings met nadelige ekologiese implikasies vir vleilande. Daar is dus tot die gevolgtrekking gekom dat beduidende voortgaande grondbedekkingveranderinge in die gebied voorkom, waarin natuurlike landdekking transformeer tot monotipiese agrobosbou, beboude nedersettings en mynbou - alles tot nadeel van die ongerepte natuurlike habitat.
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Nanwani, Shalini Suresh. "Environmental tobacco smoke and wellbeing". Thesis, Click to view the E-thesis via HKUTO, 2003. http://sunzi.lib.hku.hk/hkuto/record/B31971209.
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Sahani, Mazrura, of Western Sydney Hawkesbury University, of Science Technology and Environment College y School of Environment and Agriculture. "Separate realities : community-based environmental management for health from the 'inside-out' and 'outside-in'". THESIS_CSTE_EAG_Sahani_M.xml, 2002. http://handle.uws.edu.au:8081/1959.7/131.
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Despite the tremendous achievement in economic development over the past four decades since independence, Malaysia is facing a problem of environmental degradation at a rapid pace. In searching for Malaysian approach to alter this trend, this thesis is written against a background of concern for a balanced development in economy and social wellbeing and simultaneously preserving the environment. The aim of the study is to identify an alternative approach in managing the local environment for health, starting from a value position of regard for local knowledge and abilities, and for scientists and administrators working together with local knowledge and abilities, and for scientists and administrators working together with local communities in their natural settings. Findings from this study offer a range of lessons for those who wish to integrate local and scientific knowledge. The research approach proved capable of documenting the separate realities of the place-based and the knowledge-based communities within a common interpretative framework. The place-based communities held realistic interpretations of their capacity to contribute to local sustainable development, distinct from one another and also distinct from the same events as perceived by the scientific community. The conclusion is drawn that each needs the other for any effective local application of scientific findings or government support. Finally, this has not been a study of top-down or bottom up but from the 'inside-out' with a small study of the 'outside-in.' It offers another perspective and an extra set of tools or strategies for the professionals' community to work with local communities in their environmental management for health. The desired outcome would be for the local communities to contribute as a full partner to the dominant scientific studies in designing local management strategies.Doctor of Philosophy (PhD)
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Sompani, Thozamile Matthews. "Delivery of environmental health services to Ducats informal settlement". Thesis, Cape Technikon, 2003. http://hdl.handle.net/20.500.11838/796.
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Thesis (MTech (Environmental Health))--Cape Technikon, 2003This study provides information on the provision of environmental health services to informal housing settlements by local authorities. A standard for Environmental Health Service delivery according to Government policies and legislation has been provided. Actual environmental health services delivered to Ducats informal settlement at the time (1992), have been compared to the services that should have been delivered by law. Baseline data have been compiled by means of questionnaires, in order to assist the different levels of government in addressing the housing and environmental health needs of the Ducat community. The nature of Environmental Health and the history of informal housing, more specific that of the Ducat informal housing settlement, have been determined. Limited environmental health services were rendered to informal housing settlements occupying land illegally during 1992. These environmental health services were limited to basic sanitation, water supply and refuse removal. Only pit latrines or bucket latrines were required as a means of sanitation, tanks for water supply and skips for the disposal of waste. Amatola Regional Services Council however rendered all the environmental health services required. Other environmental health aspects such as pest control, communicable disease control, air pollution control, radiation, occupational health issues, temperature extremes, lighting, ventilation, noise, social environment, food and meat hygiene were not required. This study has provided a set of Government policies and legislation, which should be considered in rendering environmental health services for housing in future. Uncertainty of the past decade, about rendering of Environmental Health services to people occupying land illegally, still persists. The Municipal Structures Act, 117 of 1998 requires the rendering of Environmental Health services by local authorities, but it does not state whether these services should be rendered to people occupying land illegally as well. Since this has been the biggest restriction in providing environmental health services in the past, it is recommended that Government address this uncertainty.
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Tondhlana, Lawrence. "Factors affecting environmental sustainability of the downstream oil industry in Western Cape, South Africa". Thesis, Cape Peninsula University of Technology, 2018. http://hdl.handle.net/20.500.11838/2709.
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Thesis (MTech (Business Administration))--Cape Peninsula University of Technology, 2018.The oil industry has been a major contributor to economic development in many countries; providing jobs, revenue, infrastructure and businesses to third parties. However, this development has also come with adversity on the physical environment. The oil industry accounts for the highest Green House Gas (GHG) emissions in the world, making it the number one polluter. In addition, South Africa has been regarded as the biggest polluter in Africa, with fossil-based fuel cited as the major cause of environmental degradation. South Africa’s physical environment is also cited as having degraded more than most countries in Africa. This proposition requires players in the oil industry to urgently address this situation. As the future of economic development is likely to be spearheaded by the oil industry, concerns have been raised at the slow rate of addressing oil companies’ operations which causes the environment to be less sustainable. This study uses a qualitative content analysis to explore the oil companies’ actions towards addressing environmental adversity caused by their unsustainable operations. In order to be environmental sustainable, oil companies must; incorporate environmental sustainability into missions and visions, financial investment into sustainable initiatives, involve top management in environmental programs, engage stakeholder, comply and align organisational processes and operations with environmental legislations and introducing renewable energy.
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Xing, Guanhua. "Human exposure and health risk assessment of polychlorinated biphenyls at two major electronic-waste recycling sites in China". HKBU Institutional Repository, 2008. http://repository.hkbu.edu.hk/etd_ra/994.
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Ho, King-yan y 何景欣. "Ecological and human health risks associated with organotin contamination in the marine environment of Hong Kong and Shenzhen, China". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/208427.
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Organotin compounds (OTs), in particular tributyltin (TBT) and triphenyltin (TPT), have caused widespread adverse effects on marine organisms ever since their wide application as biocides in 1960s. For instance, TBT can induce the abnormal development of imposex in marine gastropods, and inhibit development and growth in oysters. A mandatory global ban on the use of OT-based antifouling systems, therefore, has been enacted by the International Maritime Organization to minimize their environmental impacts since September 2008. As a result, it is anticipated to see a reduction of OT contamination in the marine environment around the world. This study, therefore, primarily aims to test the hypothesis that there is a reduction of both OT contamination and its associated adverse impact to a common biomonitor, the rock shell Reishia clavigera along the coast in Hong Kong and Shenzhen, China through a series of field-based investigations.
Before the field study, a method was successfully developed to simultaneously quantify the concentrations of six common OTs (i.e., mono-BT, di-BT and TBT; mono-PT, di-PT and TPT) in molluscan tissues using gas chromatography-mass spectrometry. These six compounds coexist in marine environments. They are highly toxic to marine organisms and are able to induce imposex in gastropods like R. clavigera.
First, a territory-wide survey on tissue concentrations of the OTs and imposex status in R. clavigera collected from 28 coastal sites of Hong Kong was conducted in 2010. The results indicated that all female R. clavigera suffered from imposex, and all rock shells contained high TPT concentrations. A probabilistic ecological risk assessment revealed that 17.6% of R. clavigera across all sites were at risk due to exposure to TPT, whereas the risk associated with TBT was relatively low. The same species collected from Dapeng Bay and Daya Bay, Shenzhen also exhibited high tissue concentrations of TPT. Second, R. clavigera transplanted from relatively clean sites to polluted sites for six months showed increases in both imposex status and tissue concentration of OTs, confirming the association between OT contamination and imposex development. Third, a 25-month population dynamics study of R. clavigera showed a limited recruitment of the species in the polluted sites.
To verify if the observed OT contamination was widespread to other marine species in Hong Kong waters, a survey on the tissue concentrations of OTs in 11 local seafood species was conducted. Among them, the tongue sole Paraplagusia blochii had the highest tissue concentration of total OTs, with TPT as the most abundant residue. Potential health risk for consuming this benthic fish species was identified as both hazard quotient of TPT and hazard index exceeded unity.
The overall results demonstrate that the coastal marine environments in this region are still heavily contaminated with OTs especially TPT, and there is no obvious sign of recovery of R. clavigera populations. Hopefully, with further scientific investigations, both Hong Kong and China governments will take appropriate management actions to control the use and release of these priority pollutants with a view to safeguarding the marine ecosystem and human health in this region.HKU 3 Minute Thesis Award, 2nd Runner-up (2013)
published_or_final_version
Biological Sciences
Doctoral
Doctor of Philosophy
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Hung, Chui-shan Bonnie y 洪翠珊. "Human impact on the structure and water status of urban park soils in Hong Kong". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31226103.
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Kantachote, Duangporn. "The use of microbial inoculants to enhance DDT degradation in contaminated soil". Title page, contents and abstract only, 2001. http://web4.library.adelaide.edu.au/theses/09PH/09phk165.pdf.
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Wu, Yu-Tzu. "Living environment and mental health in later life". Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.709341.
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Kelly, Philip F. (Philip Francis). "Development as degradation : aquaculture, mangrove deforestation and entitlements in Batan, Philippines". Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=69616.
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This thesis examines pond aquaculture as a development strategy in the Philippines, with particular reference to its impact on the local environment and the livelihoods of local people.A theoretical framework is provided by recent literature in development studies and human geography, which attempts to move away from an essentialist and ethnocentric development praxis, and towards a locally-based, participatory process of empowerment. From the perspective of such 'alternative' development ideas, orthodox strategies involving modernization, formalization of economic activities, and resource mobilization, can be reassessed.
The promotion of pond aquaculture--and the widespread mangrove deforestation associated with it--is shown to be a strategy endorsed and supported by national and international development agencies. What is often overlooked, however, is the local ecological and economic importance of mangrove ecosystems. This study examines the effects of mangrove removal and fishpond development on the entitlements of people in three coastal communities in the Philippines. Aquacultural development is shown to have detrimental effects on the integrity of the coastal ecosystem and the livelihoods of certain groups of local residents; a rich common property resource is converted into a privately-owned system of cultivation. While benefits accrue to those with access to the capital necessary for the construction of fishponds, the costs of development are borne largely by mangrove gatherers and artisanal fisherfolk, whose share of a diminishing resource base is steadily declining. For these marginal groups, aquaculture is shown to provide few compensating economic benefits.
The study supports, through concrete local evidence, the criticisms made of orthodox approaches to development, and the need to construct attitudes and strategies which are more attuned to local sustainability and equity.
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Liang, Peng. "The effects of mariculture on mercury distribution, speciation and transformation in the aquatic system around Hong Kong coastlines". HKBU Institutional Repository, 2011. http://repository.hkbu.edu.hk/etd_ra/1291.
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Pryer, Jane Allison. "Socio-economic and environmental aspects of undernutrition and ill-health in an urban slum in Bangladesh". Thesis, University of London, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296768.
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Moore, Adam. "An Empirical Study of Particulate Matter Exposure for Transit Users at Bus Stop Shelters". PDXScholar, 2012. https://pdxscholar.library.pdx.edu/open_access_etds/870.
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Congested traffic corridors in dense urban areas are key contributors to the degradation of urban air quality. While waiting at bus stops, transit patrons may be exposed to greater amounts of vehicle-based pollution, including particulate matter, due to their proximity to the roadway. Current guidelines for the location and design of bus stops do not take into account air quality or exposure considerations. This thesis provides a unique contribution to roadside air quality studies and presents an innovative method for the consideration of bus shelter placement. Exposure to roadside pollutants is estimated for transit riders waiting at three-sided bus stop shelters that either: 1) face roadway traffic, or 2) face away from roadway traffic. Shelters were instrumented with particulate matter monitoring equipment, sonic anemometers for wind speed and direction, and vehicle counters capable of categorizing vehicles by length. Temperature and relative humidity were gathered from a nearby monitoring station. Data were collected for two different days at three shelters during both the morning and afternoon peak periods for a total of eleven data periods. Bus shelter orientation is found to significantly affect concentration of four sizes of particulate matter: ultrafine particles, PM1, PM2.5, and PM10. Shelters with an opening oriented towards the roadway were observed to have significantly higher concentrations inside the shelter than outside the shelter. In contrast, shelters oriented away from the roadway were observed to have significantly lower concentrations inside the shelter than outside the shelter. The differences in average particulate matter concentrations are statistically significant across all four sizes of particulate matter studied. Additional correlation and linear regression investigation reveals interactions between particulate concentrations and built environment characteristics, vehicle flow, and weather conditions. Temperature and relative humidity played a large role in the diurnal variation of average concentration levels. In all instances, particulate concentrations were greater during the morning period, often substantially so. Particulate concentrations are shown to vary based on both wind speed and direction. Vehicle flow is correlated with particulate levels, though significance is not consistent. Lagged vehicle flow is demonstrated to be more consistently significant. Regression analysis suggests weather factors such as wind, temperature, and relative humidity explain roughly 70% of particulate variation, while vehicle flow explains less than 6%.
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Baldridge, Jeffrey T. (Jeffrey Turner). "Psychoneurological Responses Associated with Chemicals in Serum of Environmentally Ill Patients". Thesis, University of North Texas, 1989. https://digital.library.unt.edu/ark:/67531/metadc500607/.
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The purpose of the present study was to determine the degree of relationship between neurotoxic chemicals in the blood of chemically sensitive patients and psychoneurological functioning. Blood samples were drawn from 30 patients being treated for environmental illness. All patients were administered a standardized intermediate psychoneurological examination. Results indicate a significant positive relationship between psychoneurological (cognitive neurobehavioral) functioning and the number of and total parts per billion of certain environmental toxins (solvents) in the blood of the subjects. The symptoms most commonly exhibited included deficits in short-term memory, problems with coordination and motor sequencing, somatosensory deficits, and cognitive dysfunction.
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Lockart, Esther. "Memory Patterns: Differentiated between Environmental Sensitive Patients and Psychiatric Patients". Thesis, University of North Texas, 1993. https://digital.library.unt.edu/ark:/67531/metadc278534/.
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The purpose of the present study was to ascertain if environmentally sensitive patients would demonstrate different memory deficit patterns than psychiatric patients on objectively measurable memory tasks. One-hundred sixteen patients were surveyed; 56 environmentally sensitive patients were compared to 60 psychiatric patients. All subjects were administered a Wechsler Adult Intelligence Scale-Revised screen, the Wechsler Memory Scale-Revised and the Harrell-Butler Comprehensive Neurocognitive Screen after history of head injury was ruled out. Results indicate a significantly different pattern of memory dysfunction between the environmental patients and the psychiatric patients, indicating two different etiologies. A screening device derived from the coefficients from a Canonical Analysis is proposed to distinguish between the two populations in the absence of blood serum levels of environmental toxins or poisons. The detrimental effects of misdiagnosis and the beneficial effects of accurate diagnosis of environmental illness are discussed.
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Gislason, Maya K. "Health and the environment : a critical enquiry of the construction and contestation of ecological health". Thesis, University of Sussex, 2012. http://sro.sussex.ac.uk/id/eprint/39727/.
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A crucial contemporary public health issue is the construction and contestation of the relevance of the natural world to human health. Taking a critical approach, this thesis examines how the natural environment as a health determinant is positioned in relation to the 'social' within social epidemiological studies of health, illness and disease. Using conceptual and empirical forms of enquiry, this study shows how current constructions of natural environmental health drivers contour public health practice in the UK and that by challenging the limits of existing structures, innovative responses emerge, which can generate new frameworks for health policy and practice. Having identified a lacuna in research on the 'natural' environment in medical sociology, this inductive qualitative research project brings into conversation the findings from extensive desk and field research. Specially, a study of the elaboration of environmental health discourses within the UK public health policy arena and disciplinary wide discourse analyses of key academic journals are read together to describe the discursive practices shaping environmental public health work in the UK. Linking theory to practice, data from in-depth interviews with sixty health professionals working on health and the environment in the UK and internationally are used to investigate how public health practitioners produce the environment within their work remits. The research breaks ground for further social scientific studies of health and the environment and in particular substantiates the call for an extended notion of the 'environment' using ecological principles. Methodologically, the interdisciplinary reach of this research draws attention to the tensions that arise when working across the medical, natural and social sciences. Practical and philosophical questions about the challenge of expanding the sociological imagination in the contemporary moment are also considered. Empirically, to medical sociology the 'EcoBioPsychoSocial' framework is offered as a tool for studying health at the nexus between the 'social' and the 'natural environment.' Finally, the ways informal public health institutions are serving as 'invisible' forces impeding the uptake of prevention oriented environmental health policies are findings offered to the health policy arena.
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Adam, Hassan Ali. "A solid phase microextraction/gas chromatography method for estimating the concentrations of chlorpyrifos, endosulphan-alpha, edosulphan-beta and endosulphan sulphate in water". Thesis, Peninsula Technikon, 2003. http://hdl.handle.net/20.500.11838/899.
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Thesis (MTech (Chemical Engineering))--Peninsula Technikon, Cape Town, 2003The monitoring of pesticide contamination in surface and groundwater is an essential aspect of an assessment of the potential environmental and health impacts of widespread pesticide use. Previous research in three Western Cape farming areas found consistent (37% to 69% of samples) pesticide contamination of rural water sources. However, despite the need, monitoring of pesticides in water is not done due to lack of analytical capacity and the cost of analysis in South Africa. The Solid Phase Microextraction (SPME) sampling method has been developed over the last decade as a replacement for solvent-based analyte extraction procedures. The method utilizes a short, thin, solid rod of fused silica coated with an absorbent polymer. The fibre is exposed to the pesticide contaminated water sample under vigorous agitation. The pesticide is absorbed into the polymer coating; the mass absorbed depends on the partition coefficient of the pesticide between the sample phase and the polymeric coating, the exposure time and factors such as agitation rate, the diffusivity of the analyte in water and the polymeric coating, and the volume and thickness of the coating. After absorption, the fibre is directly inserted into the Gas Chromatograph (GC) injection port for analysis. For extraction from a stirred solution a fibre will have a boundary region where the solution moves slowly near the fibre surface and faster further away until the analyte is practically perfectly mixed in the bulk solution by convection. The boundary region may be modelled as a layer of stationary solution surrounded by perfectly mixed solution.
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Boardman, Jason David. "The social determinants of health race, resources, and neighborhoods in the Detroit tri-county area /". Access restricted to users with UT Austin EID Full text (PDF) from UMI/Dissertation Abstracts International, 2002. http://wwwlib.umi.com/cr/utexas/fullcit?p3077407.
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