Browsing by Subject "Pollution"
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Item Ammonium perchlorate-induced lesions in zebrafish kidneys(Texas Tech University, 2003-12) Capps, TimAmmonium perchlorate (AP) is a highly reactive chemical that is primarily used as a rocket propellant for military and aerospace industries. Widespread AP contamination has caused increased concern over its effect on biological systems. Perchlorate derived from AP, and other perchlorate species, inhibits iodide uptake by the thyroid follicles, thus impairing the production of thyroid hormones and disrupting the regulatory feedback mechanisms of the thyroid system. As a result, the secretion of thyroid-stimulating hormone (TSH) by the pituitary gland increases. Effects of AP on other physiological systems, such as the renal system, are not well understood. The mammalian and teleost kidney are both known to contain TSH and thyroid hormone receptors, as well as iodide transport mechanisms similar to those found in thyroid follicles. Therefore, the kidney is also a potential target of direct (association with iodide transporters) or indirect (decreased thyroid hormones and increased TSH) actions of perchlorate. This study examined the histopathological effects of AP on the zebrafish kidney. Adult zebrafish were exposed to water-borne perchlorate at concentrations of 18- ppm for eight weeks and 677-ppm for 4 weeks. At the end of the exposure period, the fish were processed for histological analyses of the trunk region of the kidney. The samples were then analyzed for increased presence of macrophage aggregates, focal granulomas, inflammation, and generating nephrons. Quantitative analysis was conducted by determining the relative average area covered by a lesion in randomly selected histological sections. The results indicated that exposure to AP at 18-ppm for eight weeks caused a significant increase in the incidence of renal macrophage aggregates when compared with the control fish. The other lesions showed no changes in incidence at any AP dose. The study also suggests a link between thyroid disruption and increases in renal macrophage aggregates.Item Delta-aminolevulinic acid dehydratase (ALAD) characterization and use in metal exposure assessments(Texas Tech University, 2005-08) McFarland, Craig Alan; Hooper, Michael J.Environmental contamination as a result of anthropogenic activities has greatly increased the global availability and distribution of potentially toxic metals. Of these metals, the use of lead (Pb) by humans for millennia has resulted in Pb poisoning achieving the unfavorable distinction as the most common disease of toxic environmental origin in the United States today. Solely as a result of man’s actions, Pb has become the most widely dispersed toxic metal in the world. Methods intended to measure exposure and adverse effects of Pb have assessed the ability of living organisms to bioaccumulate the metal and to respond physiologically. Lead is a multitargeted toxicant, with hematotoxicity a primary effect, specifically inhibition of heme synthesis. ALAD is an enzyme of the heme synthesis pathway, whose inhibition in humans and animals has served as an important, and sensitive, biological marker for Pb exposure and injury. Blood samples from mammal, bird and reptile species were characterized for ALAD activity, median inhibitory Pb concentrations (IC50) and reactivation in Pb inhibited ALAD as a result of dilution in deer mice, Sprague-Dawley rats, American kestrels, prairie voles, European starlings, western diamondback rattlesnakes, Morelet’s crocodiles, Texas horned lizards and domestic pigs. Five avian and two small mammal species were collected from the Anaconda Smelter Superfund site (Deer Lodge County, MT) and assessed for ALAD activity as a biomarker of exposure to smelter-related metal contamination. Literature reviews describe blood ALAD response to environmental Pb contamination or from Pb dosing experiments in wild, captive or laboratory small mammals and birds. Results of ALAD assay development in multiple species described enzyme accuracy, hemolysate preparation, buffer selection, effect of changes in pH, blood dilution and incubation time on enzyme activity, analysis of kinetic parameters (Vmax, Km), IC50 determinations and blood dilution effects on reactivation of Pb-inhibited ALAD activity. Maximal enzyme activity was observed at pH 6.4 in all animals studied except the Texas horned lizard (pH 5.8). Dilution of blood in the American kestrel (60 to 120:1), domestic pig (30 to 120:1), prairie vole (7.5 to 120:1), deer mouse (15 to 60:1) and rat (7.5 to 30:1) demonstrated species-specific linearity of ALAD activity. Blood Vmax values varied from 7.96 to 78.95 nmol ALA/min*ml RBC in the Morelet’s crocodile and American kestrel, respectively, while Km ranged from 46.5 to 643.1 uM in the Morelet’s crocodile and Texas horned lizard, respectively. There was little difference in enzyme sensitivity (10 min IC50, µM) to in vitro Pb exposure when assessed in test species: domestic pig (1.10 ± 0.25 µM) > American kestrel (1.84 ± 0.53 µM) > deer mouse (6.27 ± 1.21 µM) > European starling (6.73 ± 0.98 uM). Reactivation of Pb-inhibited ALAD activity as a result of blood sample dilution in deer mice, Sprague-Dawley rats and domestic pigs demonstrated recovery of activity from 10 to 55%, 8 to 66% and 58 to 89%, respectively. Reactivation of enzyme activity as a result of the assay procedure suggests that an underestimation of injury to biological resources may occur when ALAD is used in assessments as defined by federal statute. Of the animals collected from the Anaconda Smelter site and assessed for blood ALAD activity, the northern pocket gopher had the most complete data to determine relationships among exposure to soil metals, tissue residues and ALAD activity. Significant relationships were determined between soil and blood Pb, soil Pb and ALAD, blood Pb and ALAD, and kidney Pb and ALAD in the pocket gopher. The interactive effects of blood Zn and Pb on ALAD activity were demonstrated using a multiple regression model and the ratio of concentrations of blood Pb and Zn (Pb/Zn). In the deer mouse, blood ALAD displayed no relationship to soil, blood or kidney Pb concentrations. Meadow vole ALAD activity was not correlated with variations in concentrations of soil Pb. Though trends were evident, American kestrel nestlings displayed non-significant relationships with blood Pb or blood Pb/Zn ratio, and ALAD activity. In the European starling, blood and kidney Pb and the blood Pb/Zn ratio significantly predicted variations in ALAD activity. Mountain bluebird blood and liver Pb and blood Pb/Zn ratio were significantly related to ALAD. In the three avian species, there was an apparent threshold for ALAD inhibition at a blood Pb concentration of 0.11 ug/g. The interaction effects of Zn and Pb on ALAD activity have been well characterized and are clear in their relative effects on the enzyme. The mechanism of ALAD inhibition is the replacement of the enzyme-bound Zn by Pb. The interaction of these metals on enzyme function is demonstrated in regression plots with the variable expression of ALAD activity under varying concentrations of blood Pb and Zn. An examination of the unusual lack of ALAD response to blood Pb concentrations in wild-collected deer mice from the Anaconda Smelter Superfund site was conducted using a laboratory-raised, wild-type conspecific (P. m. bairdii) exposed to Pb and concurrent Cu or Zn supplemented drinking water. Deer mice were dosed for 21 days with Pb acetate at 0, 0.1, 1, 10, 100, and 1000 ug/ml in drinking water that corresponded to total daily intake of Pb of approximately 0.05, 0.08, 0.4, 3, 30 and 300 mg/kg body weight. Significant elevations of tissue Pb above control were seen in the 10, 100 and 1000 ug/ml groups in blood (0.025, 0.19, 0.66 ìg Pb/g blood, respectively), and 100 and 1000 groups in liver (1.0 and 6.1 ug Pb/g liver wet wt., respectively) and kidney tissues (3.2 and 25 ug Pb/g kidney w.w., respectively). Blood ALAD activity was inhibited approximately 20, 50, and 80% at the three highest doses, consistent with findings in standard laboratory rodent species. Results of exposure to the micronutrients Zn and Cu, concurrent with effect- inducing Pb levels, were evaluated on Pb accumulation and ALAD activity. Deer mice were dosed for 28 days with Pb acetate at 0 and 100 µg/ml as well as increasing concurrent concentrations of either Cu (10 to 100 µg/ml) or Zn (30 to 300 µg/ml) in drinking water. The higher doses of both Cu and Zn led to a decreased accumulation of Pb. Zinc significantly reduced blood Pb accumulation by over 55% in the highest dose group. In addition, Zn protected against Pb-induced ALAD inhibition by up to 60% in the highest dose group when compared to the positive Pb control. The wide spread use and distribution of environmental Pb has negatively impacted many living organisms by inducing lethal and sublethal effects. As a sensitive biomarker of Pb exposure, the ALAD enzyme was characterized and applied in the assessment of Pb-induced toxicity in controlled laboratory small mammal studies and in wild-collected species. ALAD was responsive through a wide range of Pb exposures, from no effect levels, through levels leading to frank pathology in the kidney. ALAD activity is an appropriate measure of direct physiological response to Pb and was found to be applicable in new wildlife species under field conditions of Pb exposure.Item Delta-aminolevulinic acid dehydratase (ALAD) characterization and use in metal exposure assessments(2005-08) McFarland, Craig Alan; Hooper, Michael J.; McMurry, Scott T.; Cobb, George P.; Hoff, Dale J.Environmental contamination as a result of anthropogenic activities has greatly increased the global availability and distribution of potentially toxic metals. Of these metals, the use of lead (Pb) by humans for millennia has resulted in Pb poisoning achieving the unfavorable distinction as the most common disease of toxic environmental origin in the United States today. Solely as a result of man’s actions, Pb has become the most widely dispersed toxic metal in the world. Methods intended to measure exposure and adverse effects of Pb have assessed the ability of living organisms to bioaccumulate the metal and to respond physiologically. Lead is a multitargeted toxicant, with hematotoxicity a primary effect, specifically inhibition of heme synthesis. ALAD is an enzyme of the heme synthesis pathway, whose inhibition in humans and animals has served as an important, and sensitive, biological marker for Pb exposure and injury. Blood samples from mammal, bird and reptile species were characterized for ALAD activity, median inhibitory Pb concentrations (IC50) and reactivation in Pb inhibited ALAD as a result of dilution in deer mice, Sprague-Dawley rats, American kestrels, prairie voles, European starlings, western diamondback rattlesnakes, Morelet’s crocodiles, Texas horned lizards and domestic pigs. Five avian and two small mammal species were collected from the Anaconda Smelter Superfund site (Deer Lodge County, MT) and assessed for ALAD activity as a biomarker of exposure to smelter-related metal contamination. Literature reviews describe blood ALAD response to environmental Pb contamination or from Pb dosing experiments in wild, captive or laboratory small mammals and birds. Results of ALAD assay development in multiple species described enzyme accuracy, hemolysate preparation, buffer selection, effect of changes in pH, blood dilution and incubation time on enzyme activity, analysis of kinetic parameters (Vmax, Km), IC50 determinations and blood dilution effects on reactivation of Pb-inhibited ALAD activity. Maximal enzyme activity was observed at pH 6.4 in all animals studied except the Texas horned lizard (pH 5.8). Dilution of blood in the American kestrel (60 to 120:1), domestic pig (30 to 120:1), prairie vole (7.5 to 120:1), deer mouse (15 to 60:1) and rat (7.5 to 30:1) demonstrated species-specific linearity of ALAD activity. Blood Vmax values varied from 7.96 to 78.95 nmol ALA/min*ml RBC in the Morelet’s crocodile and American kestrel, respectively, while Km ranged from 46.5 to 643.1 uM in the Morelet’s crocodile and Texas horned lizard, respectively. There was little difference in enzyme sensitivity (10 min IC50, µM) to in vitro Pb exposure when assessed in test species: domestic pig (1.10 ± 0.25 µM) > American kestrel (1.84 ± 0.53 µM) > deer mouse (6.27 ± 1.21 µM) > European starling (6.73 ± 0.98 uM). Reactivation of Pb-inhibited ALAD activity as a result of blood sample dilution in deer mice, Sprague-Dawley rats and domestic pigs demonstrated recovery of activity from 10 to 55%, 8 to 66% and 58 to 89%, respectively. Reactivation of enzyme activity as a result of the assay procedure suggests that an underestimation of injury to biological resources may occur when ALAD is used in assessments as defined by federal statute. Of the animals collected from the Anaconda Smelter site and assessed for blood ALAD activity, the northern pocket gopher had the most complete data to determine relationships among exposure to soil metals, tissue residues and ALAD activity. Significant relationships were determined between soil and blood Pb, soil Pb and ALAD, blood Pb and ALAD, and kidney Pb and ALAD in the pocket gopher. The interactive effects of blood Zn and Pb on ALAD activity were demonstrated using a multiple regression model and the ratio of concentrations of blood Pb and Zn (Pb/Zn). In the deer mouse, blood ALAD displayed no relationship to soil, blood or kidney Pb concentrations. Meadow vole ALAD activity was not correlated with variations in concentrations of soil Pb. Though trends were evident, American kestrel nestlings displayed non-significant relationships with blood Pb or blood Pb/Zn ratio, and ALAD activity. In the European starling, blood and kidney Pb and the blood Pb/Zn ratio significantly predicted variations in ALAD activity. Mountain bluebird blood and liver Pb and blood Pb/Zn ratio were significantly related to ALAD. In the three avian species, there was an apparent threshold for ALAD inhibition at a blood Pb concentration of 0.11 ug/g. The interaction effects of Zn and Pb on ALAD activity have been well characterized and are clear in their relative effects on the enzyme. The mechanism of ALAD inhibition is the replacement of the enzyme-bound Zn by Pb. The interaction of these metals on enzyme function is demonstrated in regression plots with the variable expression of ALAD activity under varying concentrations of blood Pb and Zn. An examination of the unusual lack of ALAD response to blood Pb concentrations in wild collected deer mice from the Anaconda Smelter Superfund site was conducted using a laboratory-raised, wild type conspecific (P. m. bairdii) exposed to Pb and concurrent Cu or Zn supplemented drinking water. Deer mice were dosed for 21 days with Pb acetate at 0, 0.1, 1, 10, 100, and 1000 ug/ml in drinking water that corresponded to total daily intake of Pb of approximately 0.05, 0.08, 0.4, 3, 30 and 300 mg/kg body weight. Significant elevations of tissue Pb above control were seen in the 10, 100 and 1000 ug/ml groups in blood (0.025, 0.19, 0.66 ìg Pb/g blood, respectively), and 100 and 1000 groups in liver (1.0 and 6.1 ug Pb/g liver wet wt., respectively) and kidney tissues (3.2 and 25 ug Pb/g kidney w.w., respectively). Blood ALAD activity was inhibited approximately 20, 50, and 80% at the three highest doses, consistent with findings in standard laboratory rodent species. Results of exposure to the micronutrients Zn and Cu, concurrent with effect- inducing Pb levels, were evaluated on Pb accumulation and ALAD activity. Deer mice were dosed for 28 days with Pb acetate at 0 and 100 µg/ml as well as increasing concurrent concentrations of either Cu (10 to 100 µg/ml) or Zn (30 to 300 µg/ml) in drinking water. The higher doses of both Cu and Zn led to a decreased accumulation of Pb. Zinc significantly reduced blood Pb accumulation by over 55% in the highest dose group. In addition, Zn protected against Pb induced ALAD inhibition by up to 60% in the highest dose group when compared to the positive Pb control. The wide spread use and distribution of environmental Pb has negatively impacted many living organisms by inducing lethal and sublethal effects. As a sensitive biomarker of Pb exposure, the ALAD enzyme was characterized and applied in the assessment of Pb-induced toxicity in controlled laboratory small mammal studies and in wild-collected species. ALAD was responsive through a wide range of Pb exposures, from no effect levels, through levels leading to frank pathology in the kidney. ALAD activity is an appropriate measure of direct physiological response to Pb and was found to be applicable in new wildlife species under field conditions of Pb exposure.Item Drawn in bloodlines : blood, pollution, identity, and vampires in Japanese society(2012-05) Miller, Benjamin Paul; Cather, Kirsten; Maclachlan, PatriciaThis thesis is an examination of the evolution of blood ideology, which is to say the use of blood as an organizing metaphor, in Japanese society. I begin with the development of blood as a substance of significant in the eighth century and trace its development into a metaphor for lineage in the Tokugawa period. I discuss in detail blood's conceptual and rhetorical utility throughout the post-Restoration period, first examining its role in establishing a national subjectivity in reference to both the native intellectual tradition of the National Learning and the foreign hegemony of race. I then discuss the rationalization of popular and national bloodlines under the auspices of the popular eugenics movement, and the National Eugenics Bill. Then, I discuss the racialization this conception of blood inflicted on the Tokugawa era Outcastes, and its persistent consequences. Through the incongruity of the Outcastes ability to "pass" despite popular expectations that their blood pollution was visibly demonstrative, I introduce the notion of blood anxiety. Next, I address the conceptual and rhetorical role blood played in articulating Japan's empire and imperial ambitions, focusing on the Theory of Common Descent and the Investigation of Global Policy with the Yamato Race as Nucleus report. I follow this discussion with a detailed examination of the postwar reconceptualization of national subjectivity, which demands native bloodlines and orthodox cultural expressions, and which effectively de-legitimized minority populations. As illustration of this point, I describe the impact of this new subjectivity on both the Zainichi and the Nikkeijin in lengthy case studies. Finally, I conclude this examination with a consideration of blood ideology's representation in popular culture. I argue that the subgenre of vampire media allegorizes many of the assumptions and anxieties surrounding blood that have developed since the Restoration, and demonstrates the imprint of blood ideology on contemporary society.Item Metagenomic investigation of the antibiotic resistance in coastal marine ecosystemsTallman, James Joseph IIIItem The metallic elephant in the room : short range flights, high-speed rail, and the environment(2011-05) Johnson, Donovan Theodore; Zhang, Ming, 1963 Apr. 22-; Loftus-Otway, Lisa D.It is of nearly universal acceptance that one of the pillars of American economic success over the course of the 20th century was the rapid development of infrastructure. Transportation infrastructure has been of particular importance in the rise of the United States and attributed to the spread of an increasingly mobile culture. Americans undoubtedly enjoy traveling, and the ability to do so with relative ease is of immense value to many. In Texas, the majority of economic activity takes place within what is colloquially known as the “Texas Triangle”, an area bounded by the large metropolitan areas of Houston, Dallas-Ft. Worth, and San Antonio. Intensive population growth in Texas, anchored by the triangle, has led to increasing road congestion on many routes, especially along Interstates 35 and 10. This congestion, and the wasted time and money that comes with it, are of increasing concern to the future economic vitality of the state. The Texas Triangle is also served by extensive aviation links via major airports in the major metropolitan areas, as well as smaller airports in other parts of the region. These flights, operated by American Airlines, Continental Airlines, and Southwest Airlines are frequent, but emit large amounts of greenhouse gases that contribute to ground level pollution and possibly climate change. High-speed rail has been considered by many to be a superior environmental option for intercity routes with lengths inherent to the Texas Triangle. However, given the fact that Texas is the top emitter of carbon dioxide in the U.S. and relies on an energy mix that is primarily fossil fuel powered; would a potential high-speed rail in Texas outperform the current air system environmentally, given similar passenger miles traveled? This report examines the environmental emissions of high-speed rail and compares it to the environmental emissions of our current aviation system, taking into account a life-cycle perspective.Item Pollution control for cotton gin effluents(Texas Tech University, 1971-08) Page, Gordon C.Not availableItem The Effects of Corporate and Community Characteristics on Environmental Pollution in U.S. Electrical Generating Facilities: A Multilevel Examination(2011-05-18) Touche, George 1967-This dissertation uses multilevel modeling to examine the effects of corporate and community characteristics on rates of sulfur dioxide emitted by facilities in the electrical power industry. The conceptual framework draws from ecostructural theory to emphasize the social-structural causes of pollution. It also draws from organizational resource dependence theory and the shareholder conception of value. This framework suggests the contemporary transformation in corporate form and the changes in the basic relationship between the corporation and its shareholders have created dependencies, opportunities, and incentives that affect pollution. At the local community level, the conceptual framework also draws from theoretical insights of environmental justice scholars and other scholars in the environmental sociology and social-movement literature. The power plants examined in this dissertation are owned by the largest corporations in the electrical power industry and are located in many different communities across the United States. The multilevel models include three corporate characteristics and four local community characteristics as independent variables. They also include several facility and local community characteristics as control variables. In accordance with ecostructural theory, the findings demonstrate that the total number of subsidiaries in the corporate structure and the dividend payments to shareholders have significant positive effects on the power plant emissions rates. The analysis of community demography shows that relationships involving the power plant emissions rates and percent African Americans, percent families in poverty, and median home values are contingent on the geographic unit of analysis. Hence, the demographic analysis does not consistently support any theory of environmental inequality. On the other hand, all models show that the prevalence of non-profit organizations in the county has a significant negative effect on the power plant emissions rates. This follows in accordance with both ecostructural theory and the path of least resistance theory that underpins the sociopolitical model of environmental inequality. Lastly, all models show that facility control variables involving size, age, and fuel mix have significant effects on the emissions rates. In sum, this dissertation brings together and simultaneously tests theoretical insights from several lines of research to demonstrate that different levels of social structure explain environmental pollution.Item Three Essays on the Relationship between Economic Development and Environmental Quality(2014-05-30) Pancharatnam, PadmajaThis thesis is concerned with examining the relationship between indicators of economic growth and environmental quality. During this process, the analysis explores and attempts to interlink the following theoretical and empirical frameworks: Angelsen and Kaimowitz?s theories for deforestation, the Environmental Kuznets Curve (EKC) hypothesis and the forest transition theory. Macro-level data are used to examine the implications of these frameworks. The implications of the first essay suggest that different crops have a different impact on rate of change of agricultural land use. The second analysis suggests that the results from a Directed Acyclical Graph Approach present a uni-directional causal relationship between income and pollution emissions. The third and final essay suggests that property rights structures and economic incentives appear to be the most probable explanations for the forest transition in India. The macro-level nature of the data sets employed provides information on the broad trends and patterns. For policy recommendations, a more detailed and specific analysis needs to be carried out concentrating on a certain region.Item Toxicological effects and kinetics of perchlorate on fishes(Texas Tech University, 2003-08) Park, June-WooNot availableItem Understanding Kabwe's lead pollution(2014-12) Chilongo, Owen Chasoba; Spence, David B.To understand why Kabwe, Zambia is one of the most lead polluted towns, one has to look at the source of this pollution and its extent. With a history of poor environmental regulation, policies, and public information, the lead pollution caused by mining activities in Kabwe went unmitigated for decades. The natural blood-lead level in humans is about 0.0016 µg/dl, in developed countries like the United States, strict enforcement has resulted into lead levels averaging figures below 10 µg/dl, but in Kabwe, averages lie between 60 µg/dl and 120 µg/dl. Levels over 10 µg/dl are unhealthy, while levels above 20 µg/dl can cause acute poisoning whereas levels over 120 µg/dl often result into death. New environmental and rehabilitation laws were only enacted after a new administration came into office in 1991; however, additional mitigation measures such as obtaining a reclamation bond prior to being issued a mining permit need to be considered.Item Water pollution and indigenous identity : a perspective from a cooperative water association called La Sociedad de Aguas La Guadalupana(2011-12) Aparicio-Soriano, Leticia; Hale, Charles R., 1957-; Menchaca, MarthaThe water and land located in Tehuacán, Puebla, México, and its surrounding villages including San Francisco, Altepexi has provided individuals with food, jobs, and agricultural products. Currently, the descendants of these indigenous communities find their cultural, social and economical practices related to the daily use of water under threat of disappearance. A primary focus in this thesis is the pollution of water by the maquiladora industry, and pork and chicken processing. Community cooperative associations such as La Guadalupana work by administering the use of water in the villages. Scarcity and water pollution undermine one of their main sources of income to support their families. Furthermore, the health of members of the community, the peasant work activities related to water management, and the prevention of the population on their right to access to clean water are some of the social aspects that are targeted here. As a result, this thesis will explain the extent to which the autonomous Sociedad de Aguas La Guadalupana is playing a role in addressing the problem of water pollution, through a campesino way of organizing.