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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
411

Diagnostic techniques for detecting exposure and anemia in birds exposed to crude oil

Fallon, Jesse Andrew 27 July 2022 (has links)
Oil spills have long been recognized as a significant threat to wildlife. Historically, mortality estimates have served as the basis for assessing impact to natural resources. However, these mortality estimates alone neglect the more wide-spread impact of oil spills on wildlife including birds, many of which may not immediately succumb to exposure, but instead suffer sublethal injury that may negatively affect physiological homeostasis, reproduction, and long-term survival. Therefore, there is a need to improve our understanding of the risk of exposure and effect of sublethal oiling during damage assessments. In this dissertation I evaluated the extent of sublethal oil exposure in the immediate aftermath of the Deepwater Horizon spill on American oystercatchers (Haematopus palliatus), black skimmers (Rynchops niger), brown pelicans (Pelecanus occidentalis), clapper rails (Rallus crepitans), and seaside sparrows (Ammodramus maritimus) through both visual evaluation of and under the application of ultraviolet light to individual birds potentially exposed to oil. I found that there were many individual birds with modest oil exposure, demonstrating that more birds are exposed to oil than are accounted for by mortality estimates. Additionally, I developed a field-adapted technique using an in vitro method in brown pelicans that was effective in determining oxidative hematologic injury as measured by a suite of parameters including a reduction in circulating erythrocytes and hemoglobin, formation of Heinz bodies, and an increase in reticulocytes, in birds exposed to oil. I then applied this suite of parameters to individual birds affected in the aftermath of the Deepwater Horizon spill, and found that birds with modest visible or UV-detectible oil exposure suffer hematologic injury, a quantifiable adverse sublethal effect of modest oil exposure. Finally, I used an experimental approach to evaluate the pathologic effects of crude oil exposure in zebra finches (Taeniopygia guttata), evaluating the same suite of hematologic parameters as well as gross pathology, histopathology, and electron microscopy. This controlled study provided evidence that there may be significant variability in the response of birds to oil exposure that may be attributable to species-specific sensitivity and/or other factors such as the use of dispersants after oil spills. Collectively, this body of work demonstrated that many more birds are exposed to oil during spill events than are accounted for by mortality estimates alone, and that these birds can suffer quantifiable sublethal hematologic injury. The ability to accurately assess the extent of exposure and hematologic damage caused by oil spills is critical to determine the appropriate approach to management needed to offset impacts to fisheries, wildlife, habitats, and economic resources impacted by oil spills. / Doctor of Philosophy / Fossil fuels are the world's primary energy source and are an important part of everyday life. Our reliance on petroleum requires extraction, transportation, storage, and refinement of millions of gallons of crude oil each day. As an unintended consequence, some of this oil is inadvertently spilled into the environment, and these oil spills have long been recognized as a threat to wildlife. Assessing the impact of oil spills on wildlife is a major concern to industries, government, and the general public. Historically, mortality estimates have served as the basis for assessing impact to natural resources. However, these mortality estimates alone neglect the more wide-spread impact of oil spills on wildlife including birds, many of which may not immediately succumb to exposure, but instead suffer sublethal physiologic injury that negatively affects physiology, reproduction, and long-term survival. Therefore, there is a need to improve our understanding of the risk of exposure and effects of sublethal oiling during damage assessments. In this dissertation, I evaluated the extent of sublethal exposure to oil from The Deepwater Horizon spill for several species of birds through both visual evaluation of and under the application of ultraviolet light. This demonstrated that many more birds are affected by oil exposure than are accounted for by mortality estimates. Additionally, I developed a field-adapted technique in a controlled setting that is effective in determining oxidative injury to red blood cells in birds exposed to oil, and applied this approach to several species in the field during the aftermath of the Deepwater Horizon spill. Finally, I used an experimental approach to evaluate the extent of pathologic effects of Deepwater Horizon crude oil exposure in individuals under controlled dosages. The ability to accurately assess the extent of damage caused by oil spills is critical to determine the appropriate approach to management needed to offset impacts to fisheries, wildlife, habitats, and economic resources impacted by oil spills.
412

Air Quality in Mexico City: Spatial and Temporal Variations of Particulate Polycyclic Aromatic Hydrocarbons and Source Apportionment of Gasoline-Versus-Diesel Vehicle Emissions

Thornhill, Dwight Anthony Corey 21 August 2007 (has links)
The Mexico City Metropolitan Area (MCMA) is one of the largest cities in the world, and as with many megacities worldwide, it experiences serious air quality and pollution problems, especially with ozone and particulate matter. Ozone levels exceed the health-based standard, which is equivalent to the U.S. standard, on approximately 80% of all days, and concentrations of particulate matter 10 μm and smaller (PM10) exceed the standard on more than 40% of all days in most years. Particulate polycyclic aromatic hydrocarbons (PAHs) are a class of semi-volatile compounds that are formed during combustion and many of these compounds are known or suspected carcinogens. Recent studies on PAHs in Mexico City indicate that very high concentrations have been observed there and may pose a serious health hazard. The first part of this thesis describes results from the Megacities Initiative: Local and Regional Observations (MILAGRO) study in Mexico City in March 2006. During this field campaign, we measured PAH and aerosol active surface area (AS) concentrations at six different locations throughout the city using the Aerodyne Mobile Laboratory (AML). The different sites encompassed a mix of residential, commercial, industrial, and undeveloped land use. The goals of this research were to describe spatial and temporal patterns in PAH and AS concentrations, to gain insight into sources of PAHs, and to quantify the relationships between PAHs and other pollutants. We observed that the highest measurements were generally found at sites with dense traffic networks. Also, PAH concentrations varied considerably in space. An important implication of this result is that for risk assessment studies, a single monitoring site will not adequately represent an individual's exposure. Source identification and apportionment are essential for developing effective control strategies to improve air quality and therefore reduce the health impacts associated with fine particulate matter and PAHs. However, very few studies have separated gasoline- versus diesel-powered vehicle emissions under a variety of on-road driving conditions. The second part of this thesis focuses on distinguishing between the two types of engine emissions within the MCMA using positive matrix factorization (PMF) receptor modeling. The Aerodyne Mobile Laboratory drove throughout the MCMA in March 2006 and measured on-road concentrations of a large suite of gaseous and particulate pollutants, including carbon dioxide, carbon monoxide (CO), nitric oxide (NO), benzene (C6H6), formaldehyde (HCHO), ammonia (NH3), fine particulate matter (PM2.5), PAHs, and black carbon (BC). These pollutant species served as the input data for the receptor model. Fuel-based emission factors and annual emissions within Mexico City were then calculated from the source profiles of the PMF model and fuel sales data. We found that gasoline-powered vehicles were responsible for 90% of mobile source CO emissions and 85% of VOCs, while diesel-powered vehicles accounted for almost all of NO emissions (99.98%). Furthermore, the annual emissions estimates for CO and VOC were lower than estimated during the MCMA-2003 field campaign. The number of megacities is expected to grow dramatically in the coming decades. As one of the world's largest megacities, Mexico City serves as a model for studying air quality problems in highly populated, extremely polluted environments. The results of this work can be used by policy makers to improve air quality and reduce related health risks in Mexico City and other megacities. / Master of Science
413

Contaminants at a Shooting Range: Toxicological and Nutritional Significance to Birds and Mammals

Gonzalez, Gabriela Rae 25 August 2003 (has links)
Target shooting in the United States has become an increasingly popular sport in the last century. In addition to the large quantity of lead pellets littering range grounds and surrounding land, considerable amounts of clay target fragments cover shooting range areas as well as adjoining habitats. Polycyclic aromatic hydrocarbons (PAHs) within the target, as well as lead pellets from shotguns pose multiple threats to a variety of wildlife. To determine the effects of clay target and lead pellet ingestion on wildlife, I conducted controlled experiments on Coturnix quail exposed to clay targets in the lab, and collected wild birds and mammals exposed to lead pellets at a shooting range. The first Coturnix study determined whether quail voluntarily consumed target fragments or limestone fragments. In both fall (F=29.2, P<0.01) and spring (F=6.45, P=0.02) experiments, I found that quail consistently selected limestone fragments, but almost completely rejected clay target fragments. In the second study, quail were force-fed varying amounts of target dust on a weekly basis to simulate sporadic exposure to clay target dust. In both summer (F=1.63, P=0.23) and winter (F=0.34, P=0.8) trials, male quail did not have significant weight loss. Female quail had insignificant weight losses in summer trials (F=1.63, P=0.23) but experienced weight gains in winter trials (F=3.53, P=0.04). In the third and final Coturnix study, varying amounts of target dust were incorporated into daily feed rations to simulate frequent exposure to clay target dust. Male quail experienced weight loss in both summer (F=16.13, P<0.01) and winter (F=8.47, P<0.01) trials. Female quail also suffered weight loss in both summer (F=15.62, P<0.01) and winter (F=17.50, P<0.01) trials. Weight loss likely resulted from inadequate nutrition as opposed to target poisoning. However, because there were no biochemical analyses performed to test for PAH presence, no definite conclusions can be made. The second study focused on lead contamination in Passeriformes, perching birds, and small mammals. Seventeen of 20 birds (85%) (Passerine spp) captured at the shooting range had elevated lead levels (F=5.21, P<0.028), when compared to birds (n=20) at the control site. Nine of 26 (35%) white-footed mice (Peromyscous leucopus), trapped at the shooting range had elevated liver (F=9.78, P=0.0029) and kidney (F=22.49, P<0.01) lead levels. These results indicate that Passerine species as well as Peromyscous species around shooting ranges inadvertently consume lead, either as lead pellets, mistaking them for grit or dietary items, or through environmental sources such as water, soil, and vegetation. / Master of Science
414

A study of the synthesis and reactions of new polynuclear aromatic acids and related compounds

Greenwood, Edward James January 1966 (has links)
The preparation of 2-(3-chloro-l-naphthylmethyl)bromobenzene was achieved by the cross-condensation reaction of 3-chloro-l-naphthylmagnesium bromide and 2-bromobenzyl bromide, as well as by the reaction of this Grignard reagent with 2-bromobenzaldehyde, followed by reduction of the resulting carbinol with lithium aluminum hydride and aluminum chloride. It was found that 2-bromophenyl-1-(3-chloronaphthyl)carbinol thermally decomposed into the corresponding methylene compound and ketone. A study of the thermally induced reaction of the carbinol was made, and the products were quantitatively analyzed by means of gas chromatography. It was concluded that the anomalous products of the reaction of an aryl Grignard reagent with a benzaldehyde were actually p~duced by the thennal disproportionation of the resulting carbinols during the distillation step. The keto-acid, 2-(3-chloro-l-naphthylmethyl)- 2’-carboxybenzophenone was prepared by the inverseaddition of the Grignard reagent of 2-(3-chloro-l-naphthylmethyl)bromobenzene to phthalic anhydride. Cyclization of this keto-acid with an acetic and hydrobromic acid mixture gave 6-chloro-7-(2-carboxyphenyl)benz[a]anthracene. Methyl ester derivatives were prepared from both this acid and the precursor keto-acid. The cyclodehydration of either 2-(3-chloro-l-naphthylmethyl)-2'-carboxybenzophenone or 6-chloro-7-(2-carboxyphenyl)benz[a]anthracene with polyphosphoric acid gave 14-chlorodibenzo[hi,l]chrysen-9-one.· Treatment of this ketone with lithium aluminum hydride and aluminum chloride gave the reduction derivative, 14-chloro-9H-dibenzo[hi,l]chrysene. The unequivocal synthesis of dibenzo[hi,l]- chrysen-9-one was achieved by the dehalogenation of 14-chlorodibenzo[hi,l]chrysen-9-one with 10% palladiumcharcoal catalyst and hydrazine. The dehalogenated product was shown to be identical to the compound produced from the cyclodehydration of 7-(2-carboxyphenyl)benz[a]anthracene. The ketone, 2-(3-chloro-l-naphthylmethyl)benzophenone was prepared by the inverse-addition of the Grignard reagent of 2-(3-chloro-l-naphthylmethyl)- bromobenzene to benzoyl chloride. It was found that a small amount (16%) of 6-chloro-7-phenylbenz[a]-anthracene was formed during the distillation of the precursor ketone. The cyclodehydration of this ketone failed when various standard cyclizing media were employed, and the reason for this is discussed. Cyclization attempts with polyphosphoric acid or alumina gave dibenzo[a,l]pyrene as the only identifiable product. This unusual reaction obviously involves a rearrangement. A study was made and a mechanism for this reaction was postulated which is consistent with the experimental observations. The ketone, 2-(3-cyano-l-naphthylmethyl)benzophenone was prepared by the reaction of the corresponding chloro ketone with cuprous cyanide in N-methylpyrrolidone. 6-Cyano-7-phenylbenz[a]- anthracene was also produced in small quantity in this reaction as a consequence of the presence of the corresponding chloro compound in the ketone prior to reaction. Naphtho[3, 2, l-fg]naphthacen-9-one was prepared by the treatment of 6-cyano-7-phenylbenz[a]anthracene with a hydrobromic and acetic acid mixture at 180°, and also by the treatment of the precursor cyano ketone with polyphosphoric acid. The novel use of polyphosphoric acid in cyano group hydrolysis is discussed. Phenalo[2, 3, 4, 5-defg]naphthacene-4, 8-quinone was prepared by the treatment of 6-cyano-7-(2-carboxyphenyl)benz[a]anthracene with a hydrobromic and acetic acid mixture at 180°. An attempted procedure for the. preparation of this quinone involved the oxidation of 7-(2,6-dimethylphenyl)benz[a]anthracene to the corresponding diacid with aqueous sodium dichromate. Unfortunately this new method of oxidation failed in this case. The partial resolution of 7-(2-carboxyphenyl)-benz[a]anthracene was achieved with the use of brucine. Only one optically active isomer was obtained, and this was racemized by treatment with boiling ethanol. An empirical rule used to quantitatively determine the resistance of optically active biphenyls to racemization was applied to this acid, and the experimental observations were supported. During the course of this investigation, sixteen new compounds were prepared and were all properly characterized, except 6-cyano-7-(2-carboxyphenyl)- benz[a]anthracene, which did not give acceptable analytical data. The reason for this is discussed. Infrared and ultraviolet spectra of all new compounds were recorded. Infrared spectral observations were made which gave further support to the assigned structures of the isomeric compounds naphtho[3,2,l-fg]- naphthacen-9-one and dibenzo[hi,l]chrysen-9-one. / Doctor of Philosophy
415

Complexation of metal salts with phosphorus-containing poly(arylene ether)s

Bonaplata Revilla, Elena 21 July 2009 (has links)
Poly(arylene ether phosphine oxide)s (PEPO) are a recently identified subset of an important macromolecular series which includes industrially important high performance thermoplastics, such as the polysulfones, e.g. UDEL@ and polyether ketones, e.g. PEEK@, PEKK@, etc. The PEPO materials show an elevated glass transition temperature, high thermal and oxidative stability, improved solubility, and increased flame resistance. It has been demonstrated that a variety of metal salts including metals such as iron, zinc, cobalt, and copper, can be complexed at a molecular level with the phosphoryl group in films of these polymers producing novel transparent metal/polymer "composites". A procedure for obtaining homogeneous films from solutions of the metal halide complexed polymers has been developed. FTIR experiments as well as Tl phosphorus (31 P) NMR measurements were conducted to demonstrate the existance of metal complexation in the solid state. The effect of the chemical composition of the chain, type of metal salt, molar concentration of the metal salt, and heating cycle were investigated and found to influence properties of the films such as solubility, glass transition temperature, thermal stability, and storage mexiulus. Additionally, linear poly(arylene ether phosphine oxide)s were reduced to different extents to the corresponding phosphine containing polymers. Properties such as intrinsic One of these phosphine polymers was subsequently used in the generation of a rhodium catalyst for the hydroformylation of octene-l. The utilization of polymer-supported catalysts has important advantages such as catalyst recovery and the ease of separation of the product. The catalyst activity of the polymeric rhodium complex was studied as a function of reaction time as well as ligand to rhodium ratio. For a phosphorus/rhodium ratio of two these heterogeneous catalysts suffer in tenns of reaction rate in relation to their homogeneous counterparts. However, at phosphorus/rhodium ratios of approximately eight the reaction is almost quantitative after three hours, and the selectivity is greatly improved over that of monomeric homogeneous catalysts for the same P/Rh ratio. / Master of Science
416

Relationships Between Hybrid Poplar Tree Extractives and Ground Water Contamination at a Phytoremediation Site

Waters, Lois Diane 04 April 2003 (has links)
In 1997, a phytoremediation program began at a creosote-contaminated former railroad tie yard in Oneida, Tennessee with the planting of over 1000 hybrid poplar trees onsite. Creosote, a mixture of hazardous chemicals composed of 85% polycyclic aromatic hydrocarbons (PAH) had entered the site soil and ground water. After planting, a seasonal ground water testing program began that monitored the progress of remediation by measuring the concentration of the 10 predominant PAHs in the contaminant plume: naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, chrysene, and benzo(b)fluoranthene. The concentrations of these compounds steadily decreased over time, but the role the trees played in the remediation was unclear. In order to gain a clearer understanding of the role the trees played in contaminant remediation, chemical analysis of tree tissue began. It was not known whether the trees were taking up PAH contaminants or their metabolites or if the rhizosphere zone created by the trees simply enhanced the ability of the site microflora to degrade the PAH. The objectives of this research were to (1) develop a suitable method for the chemical analysis of tree tissue collected from a field site, (2) determine if there were any chemicals not usually found in poplar trees that occurred in the trees growing over contamination, (3) determine if bud, bark, and twig tissue differed in their ability to predict ground water contamination, and (4) determine if a spatial correlation existed between the aromatic compounds in the tree tissue and the ground water total PAH plume. Two types of tree tissue/ground water comparisons were performed: spatial distribution of isoeugenol concentration in tree tissue with spatial distribution of total PAH in ground water over the area of interest; and the spatial distribution of the quantity of aromatic compounds in tree tissue with the spatial distribution of total PAH concentration in ground water. Due to unit discrepancies between the quantities of interest, all comparisons were made on a percentile basis. Initial tree sampling revealed that several compounds not usually present in poplar trees occurred only in those trees growing over contamination. In the first part of this study, the concentration of one of these chemicals, the substituted phenol isoeugenol, was compared with the concentration of total PAH in ground water from samples collected from February-March 2002. The bark tissue percentiles fell within 20 percentiles of ground water total PAH concentrations in 60% of the study area. The twig tissue showed slightly better agreement, with 67% of the study area differing from ground water by twenty percentiles or less. The second comparison took place over three sampling events: March 2001, July 2001, and February-March 2002. The number of unique aromatic compounds in bark, bud, and twig tissue was compared with the total PAH concentration in ground water. Twig tissue aromatic compound content was the most accurate predictor of ground water contamination among the tissue types. After excluding those chemicals likely to be interferences from consideration, twig tissue aromatic content agreed with ground water total PAH concentration to within 20 percentiles over 2/3 or more of the study area during each sampling event, suggesting the potential uptake of PAHs or their microbial metabolites as a mechanism of phytoremediation at the site. / Master of Science
417

Determination of contamination by polycyclic aromatic hydrocarbons, and their mode of origin, in urban soils from Leeds (UK)

Hamed, Heiam A. Mohamed, Hale, William H.G., Stern, Ben 2018 April 1922 (has links)
No / This study aims to determine the concentration of 16 Polycyclic Aromatic Hydrocarbons (PAHs) in urban soils from Leeds in order to determine what the factors are controlling their distribution and abundances. Soil samples were collected across an area from Leeds. Gas chromatography with mass spectrometry (GC-MS) using selected ion monitoring (SIM) was used to identify and quantify PAHs in the soil samples with the aid of PAH external standards. The results showed the highest concentrations of total PAHs in sample L8 (1344 ng/g) taken from an area located near a parking site and road in Leeds and the lowest total concentration of the 16 PAHs in sample L16 (87 ng/g) taken from a private garden. The ratio of anthracene to anthracene plus phenanthrene AN/(AN + PH), fluoranthene to fluoranthene plus pyrene FLU/(PY+FLU) and benzo[a]anthracene to 228 (BaA/228) implied that the PAHs pollution originated from pyrogenic, biomass and petroleum combustion in the samples which were collected from Leeds city.
418

Determination of contamination by polycyclic aromatic hydrocarbons, and their mode of origin, in urban soils from Leeds (UK)

Hamed, Heiam A. Mohamed, Hale, William H.G., Stern, Ben 06 1900 (has links)
Yes / This study aims to determine the concentration of 16 Polycyclic Aromatic Hydrocarbons (PAHs) in urban soils from Leeds in order to determine what the factors are controlling their distribution and abundances. Soil samples were collected across an area from Leeds. Gas chromatography with mass spectrometry (GC-MS) using selected ion monitoring (SIM) was used to identify and quantify PAHs in the soil samples with the aid of PAH external standards. The results showed the highest concentrations of total PAHs in sample L8 (1344 ng/g) taken from an area located near a parking site and road in Leeds and the lowest total concentration of the 16 PAHs in sample L16 (87 ng/g) taken from a private garden. The ratio of anthracene to anthracene plus phenanthrene AN/(AN + PH), fluoranthene to fluoranthene plus pyrene FLU/(PY+FLU) and benzo[a]anthracene to 228 (BaA/228) implied that the PAHs pollution originated from pyrogenic, biomass and petroleum combustion in the samples which were collected from Leeds city.
419

The Chemistry of Ynamide and its Application in Organic Synthesis

Siyu, Y., Wu, Na (Anna) 30 March 2021 (has links)
Yes / Ynamide, is an understudied but attractive class of alkynes, activated by the donating ability of the nitrogen adjacent to alkynes. With the nucleophilicity on β-carbon and the electrophilicity on α-carbon of ynamides, this review summarizes the syntheses of ynamides and miscellaneous reactions - oxidation, rearrangement, cyclization, and cycloaddition to construct complicated heterocyclic rings. The synthetic methodologies were further applied into natural products synthesis, e.g. marinoquinolines A and C, aplidiopsamine A, rigidin A, and 7-azaserotonin derivative. / We thank National Science Foundation of China (NSFC) (21462004), State Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (CMEMR2014-A04), 2015 GXNSFBA (139032), GXNU, and Newton International Fellowship granted by Royal Society.
420

A técnica de Blue rayon in situ associada ao teste Salmonella/microssoma como estratégia para o monitoramento de águas estuarinas quanto à presença de compostos policíclicos genotóxicos / The Blue rayon technique in situ associated with the Salmonella / microsome test as a strategy for monitoring estuarine waters for the presence of genotoxic polycyclic compounds

Kummrow, Fábio 07 March 2006 (has links)
O estuário de Santos abriga o maior porto da América Latina e um dos maiores complexos industriais do Brasil. Na década de 1970 foi considerado um dos maiores exemplos de degradação ambiental em ambientes costeiros, e apesar da melhora na qualidade ambiental observada nos últimos anos algumas áreas deste estuário apresentam sedimentos ainda altamente contaminados com compostos tóxicos e genotóxicos, especialmente os Hidrocarbonetos Policíclicos Aromáticos (HPA). Operações de dragagem para manutenção das atividades portuárias são necessárias e consequentemente durante este processo pode ocorrer a ressuspensão de contaminantes presentes nesses sedimentos, tornando-os disponíveis novamente na coluna d\'água. Desta forma é interessante ter uma estratégia eficiente e aplicável no monitoramento da qualidade dessas águas. O Blue rayon (BR) é um adsorvente seletivo para compostos policíclicos com três ou mais anéis fundidos em sua molécula e tem sido utilizado com sucesso no monitoramento de HPA e atividade mutagênica em ambientes aquáticos. Este trabalho teve como objetivo padronizar o uso da técnica de Blue rayon in situ ancorado, onde as fibras são fixas a uma distância padronizada dos sedimentos, associada ao teste de Salmonella/microssoma em microssuspensão a ser aplicada no monitoramento das águas desse estuário. Foram selecionados três pontos de amostragem com diferentes características e sedimentos com variados níveis de contaminação. As duas campanhas iniciais foram realizadas com o objetivo de avaliar a eficiência do BR e de escolher a linhagem de Salmonella mais sensível aos compostos mutagênicos possivelmente presentes nos extratos obtidos bem como verificar a presença de HPA. As cinco campanhas posteriores foram realizadas para verificar o comportamento e a eficiência da estratégia previamente definida no monitoramento das águas desse estuário utilizando experimentos de dose resposta. Os resultados obtidos nas duas primeiras campanhas mostraram que as águas do ponto 1, que contém os sedimentos mais contaminados e recebe os efluentes da COSIPA, apresentam maior contaminação por HPA e atividade genotóxica mais elevada que o ponto 2. Também foi possível determinar que a linhagem de Salmonella YG1041 foi a mais sensível para detectar atividade mutagênica tanto no ponto 1 quanto no ponto 2. Nas cinco campanhas subsequentes as maiores potências mutagênicas foram também observadas no ponto 1 com valores máximos de 5.100 e 36.000 revertentes/g de BR para a linhagem YG1041 na ausência e na presença de ativação metabólica (S9) respectivamente. Nos pontos 2 e 3 as potências observadas foram similares entre si, com valores em torno de 1.000 revertentes/g de BR. Com base nos resultados obtidos nas duas etapas deste trabalho pode-se concluir que a o Blue rayon utilizado in situ a uma distância padronizada dos sedimento associado ao teste de Salmonella/microssoma em microssuspensão com a linhagem YG1041 na presença e na ausência de ativação metabólica (S9) é uma ferramenta que pode ser aplicada no monitoramento da qualidade do estuário de Santos. / Santos estuary is the major Latin American harbor and one of the largest industrial complex of Brazil. In the 1970s, it was considered one of the major examples of coastal degradation. Due to enforcement actions the quality of the environment has improved in the last years in relation to the chemical parameters and toxicity but unfortunately the sediment is still contaminated with toxic and genotoxic compounds especially Polycyclic Aromatic Hydrocarbons (PAHs). For the maintenance of the port activities sediment dredging is needed and during this process contaminants resuspension can occur, leading to the contamination of the water column. Therefore it is interesting to have an efficient strategy that can be used for the water quality monitoring of this area. The Blue rayon is a selective adsorbent to polycyclic compounds containing three or more fused rings and has been successfully used in the monitoring of PAHs and mutagenic activity in aquatic environments. The objective of this work was to evaluate a modified blue rayon hanging technique, denominated in this work \"Blue rayon anchored technique\", where the fibers are placed at a fixed distance from the sediment, associated with the Salmonella/microsome microsuspension assay in order to monitor the water quality of Santos estuary. Three sites with different sources and sediment contamination levels were selected in this study. Two initial samplings were performed in order to evaluate the efficiency of the BR modified technique and find the most sensitive strain of Salmonella typhimurium to the mutagens possibly present in the those waters as well as verify the presence of PAHs. Five subsequent samplings were performed to verify the performance and efficiency of the defined strategy in the estuary water quality monitoring using dose response experiments. In the two initial samplings, the water from the site containing the most contaminated sediment and under influence of COSIPA (site 1) presented higher mutagenic activity and higher levels of PAHs. It was also possible to verify the highest sensitivity of the YG1041 strain in the detection of the mutagenic activity in both sites analyzed. In the subsequent five samplings, higher mutagenic potencies were again observed for site 1, reaching 5,100 and 36,000 revertants per gram of BR for the YG1 041 strain in the absence and presence of S9 respectively. Sites 2 and: presented similar potencies, around 1000 revertants per gram of BR. Based on the obtained results we can conclude that the Blue rayon anchored technique associated with the Salmonella/microsome microsuspension assay with the YG1041 strain in the presence and absence of S9 is an suitable tool to monito Santos estuarine waters.

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