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Thesis (Ph. D.)--University of Alberta, 2010. / Title from pdf file main screen (viewed on June 18, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Environmental Engineering, Department of Civil and Environmental Engineering, University of Alberta. Includes bibliographical references.

The longterm fate of petroleum in four marine environments was Investigated: The fate of petroleum on the surface of the ocean was elucidated by undertaking a detailed study of petroleum residues polluting the Pacific Ocean. First, the extent of contamination of the Pacific by petroleum residues was assessed by measuring the amounts of tar in 2092 neuston tows over a nine-year period (1967-1975). The South Pacific was found to be free of tar; the Northeast Pacific was slightly polluted, with an average of 0.03 mg/m² . The Northwest Pacific, particularly the Kuroshio current system, was the most severely polluted area: all 55 tows between 25° and 40°N in the Northwest Pacific were contaminated. The average concentration in that area 2 was 2.1 mg/m² , representing a standing stock of about 25,000 metric tons of tar. Chemical analyses of the tar as well as its distribution pattern strongly imply that it originates primarily from tanker traffic, and from tanker sludge in particular. The pollutants appear to be discharged by tanker on the very large Middle East to Japan tanker route, then become entrained in the Kuroshio current and create a plume of contamination which extends downstream for 7000 kilometers across the Pacific. Initially evaporation is the most important weathering mechanism acting on the tar, removing component up to the volatility of pentadecane over a period of days or perhaps weeks. Thereafter, microbial degradation is dominant, probably acting for over a year on many particles. Both of these processes increase the density of the residues, and this effect, combined with the overburden of fouling growth that develops, eventually results in the slow sinking of the tar into the depths of the ocean. The fate of petroleum in the intertidal environment was studied by following the natural degradation of the oil after a small (200 ton) oil spill of #5 fuel oil. The most important weathering process was microbial degradation. Evaporation played only a minor role, while photo-oxidation and dissolution had no apparent effect. The microbal attack took approximately one year to complete the degradation of the n-paraffin fraction of the spilled oil, leaving a thin asphaltic residue on the beach. The combined effect of microbial degradation and abrasive weathering removed roughly 95% of the oil from the beach over the period of a year. The fate of oil in the benthic environment was studied by treating 500 ml quantities of crude oil with a commercial sinkant, then placing the oil on soft sediments in about 6 meters of water. Again in the benthic environment, microbial action was the process responsible for the degradation of the oil. Evaporation had no opportunity to act, dissolution was ineffective, and photo-oxidation did not occur because of the low energy and intensity of the light reaching the sediment. The benthic petroleum samples were slow to degrade: the oil remained unchanged in chemical composition for at least 6 months, and after 16 months the n-paraffins were only partly degraded. Oil dissolved in the water column was investigated by adding a spike of #2 fuel oil to an enclosed column of water 2 m in diameter by 15 m deep, and monitoring its fate by fluorescence spectroscopy. For water a meter or two in depth, exchange with the atmosphere played the dominant role in removing the hydrocarbons from the water column, but at 7 m and below, microbial degradation and sedimentation were the more important processes. The disappearance of the oil approximately followed an exponential decay curve. The half life for a large dissolved oil spike was about 3 days (less for a smaller spike) so that 95% removal occurred within 2 weeks. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

Thesis (M.S.)--West Virginia University, 1998. / Title from document title page. Document formatted into pages; contains xv, 233 p. : ill. Includes abstract. Includes bibliographical references (p. 227-232).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1982. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 142-153).

Submitted in partial fulfillment of the requirements for the Degree of Masters of Technology: Mechanical Engineering, Technikon Natal, 1998. / The two and a half billion dollars spent in cleaning up the Exxon Valdez spill in Prince William Sound is one of many indications of how seriously environmental damage is viewed today. Due to the massive problems encountered during spills, clean-ups remain time consuming and costly. Thus the aim of this study is to develop a more efficient method, which will be the design and development of an oil reclaimer to operate in moderate sea conditions. The feasibility of the concept will be evaluated against existing methods. / M

Thesis (M.Sc.)--Memorial University of Newfoundland, 2001. / Bibliography: leaves 117-125.

The purpose of this study was to assess the effects of water-soluble fractions (WSF) of naphthalene, phenanthrene, No. 2 fuel oil, and coal-tar creosote on the survival, growth, reproduction, feeding, and metabolism of Daphnia pulex. The 48 hr LC50 values after acute exposure (as percent WSF) for creosote, No. 2 fuel oil, phenanthrene and naphthalene were 2.91, 34.10, >>100, and 57.52 percent, respectively. Gas chromatography analysis indicated naphthalene and phenanthrene 48 hr LC50 values (as mg/1) were 2.92-3.89 and 0.96-1.28, respectively. Up to 40 peaks were noted in each stock WSF of creosote and No. 2 fuel oil. For chronic studies, young (24 hr) Daphnia were exposed to calculated LC20 and LC30 concentrations of WSF's for their entire life. The LC30 concentrations of creosote and phenanthrene showed a significant reduction in growth rate and number of live young, as well as reduced number of broods, impairment of molting, and significant delay in reproductive maturation; instances of possible neoplasms were also noted in one organism from each of these test groups. No. 2 fuel oil produced similar effects on growth and reproduction, but results were not as significant. Increased longevity and slight reduction in growth rate were noted for both naphthalene test groups. The effects upon oxygen consumption after exposure to test WSF's were variable. The LC30 concentration of creosote and both naphthalene concentrations were significantly different from each other; both naphthalene concentrations elicited the lowest oxygen consumption rates recorded, while the creosote LC30 group exhibited the highest rate of oxygen consumption. However, no experimental means were significantly different from controls. Highly significant differences existed between filtering rates of organisms after exposure to the WSF's. The LC20 concentrations of creosote and phenanthrene produced the highest and lowest filtering rates, respectively. Both oil test groups demonstrated significantly higher filtering rates. Monitoring zooplankton filtering rates appears to be a promising parameter to evaluate physiological stress on these organisms. This chronic study and data from other comparable chronic studies indicate that the length of a pre-adult Daphnia after 7 days of exposure to stress can be used to predict chronic reproductive effects with the same degree of accuracy as the 21-day test. Adoption of this test would eliminate difficulties with starvation, nutrition, and competition for food which contribute to the variability in reproductive impairment tests. A possible mechanism of action of polynuclear aromatic hydrocarbons upon endocrine systems is strongly suggested by the dramatic and diverse effects upon growth and reproduction in Daphnia pulex. / Ph. D.

Uma das principais fontes de poluição dos recursos hídricos são os efluentes líquidos industriais. Dentre esses, destacam-se os efluentes de refinaria de petróleo, pois geram efluentes bastante complexos e de difícil tratabilidade. Desta forma, evidencia-se a necessidade de monitoramento contínuo da qualidade desses efluentes, uma vez que são considerados de alto risco. Além do monitoramento físico-químico, o monitoramento biológico é uma importante ferramenta para avaliação da qualidade de efluentes. O objetivo desse trabalho foi avaliar a eficiência de quatro ensaios na determinação da toxicidade de efluente tratado de refinaria de petróleo. Foram realizados ensaios de toxicidade aguda com Daphnia magna e com bactérias aeróbias heterotróficas (Teste D), e ensaios de toxicidade crônica com Ceriodaphnia dubia e Caenorhabditis elegans. Os ensaios com D. magna seguiram a NBR 12713 (ABNT, 2004) e tiveram como endpoint a mortalidade. O Teste D foi baseado em Krebs (1985) e avaliou efeitos de estímulo ou inibição do consumo bioquímico de oxigênio (CBO). Ensaios com C. dubia avaliaram a mortalidade e a reprodução dos organismos, segundo a NBR 13373 (ABNT, 2005). Os ensaios com C. elegans foram realizados de acordo com a ISO/DIS 10872 (2009), e tiveram o crescimento e a reprodução como endpoints. As cinco amostras avaliadas foram provenientes de refinaria de petróleo do estado do Paraná. A análise estatística dos resultados mostrou que C. elegans foi o organismo mais sensível ao efluente, apresentando concentração de efeito observado (CEO) a partir de 12,5%, sendo classificado como organismo moderadamente sensível. Os ensaios com C. elegans e o Teste D apresentaram estímulo na concentração mais baixa, fenômeno conhecido como hormese. Esse fenômeno deveria ser considerado em avaliações ambientais uma vez que toda alteração na composição e estrutura de comunidades interfere na integridade dos ecossistemas. / Submitted by Marcelo Teixeira (mvteixeira@ucs.br) on 2014-06-04T19:11:31Z No. of bitstreams: 1 Dissertacao Taisa Fedrizzi Maffazzioli.pdf: 2620358 bytes, checksum: 1827f2f93568f37620ece6d1a95c3559 (MD5) / Made available in DSpace on 2014-06-04T19:11:31Z (GMT). No. of bitstreams: 1 Dissertacao Taisa Fedrizzi Maffazzioli.pdf: 2620358 bytes, checksum: 1827f2f93568f37620ece6d1a95c3559 (MD5) / One of the main sources of water pollution is industrial wastewater. Among these, stands the waste of oil refinery effluents because is quite complex and of difficult tractability. Therefore, it is evident the need for continuous monitoring of the quality of these effluents, since they are considered high risk waste. In addition to monitoring physical and chemical, biological monitoring is an important tool for assessing the quality of effluents. The aim of this study was to evaluate the effectiveness of four tests in determining the toxicity of treated wastewater of oil refinery. Were performed acute toxicity tests with Daphnia magna and heterotrophic aerobic bacteria (D Test), and chronic toxicity tests with Ceriodaphnia dubia and Caenorhabditis elegans. Tests with D. magna followed the NBR 12713 (ABNT, 2004) and had the mortality as endpoint. The D Test was based on Krebs (1985) and assessed the effects of stimulation or inhibition of biochemical oxygen consumption (BOD). Tests with C. dubia evaluated the mortality rate and reproduction of organisms, according to NBR 13373 (ABNT, 2005). Tests with C. elegans were performed according to ISO / DIS 10872 (2009), and had the growth and reproduction as endpoints. The five evaluated samples were from an oil refinery in the state of Parana, Brazil. The statistical analysis showed that C. elegans was the most sensitive organism to the effluent, presenting the observed effect concentration (OEC) from 12.5%, which classified it as moderately sensitive organism. Tests with C. elegans and the D Test showed low-dose stimulation, a phenomenon known as hormesis. This phenomenon should be considered in environmental assessments because every change in communities composition and structure interferes in the ecosystems integrity.