Bibliography: leaves 235-265. / xvi, 265 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Examines the tumour promoting effects of the microcystins through a long-term study in which cyanobacterial extract containing a range of microcystins was given in drinking water to mice previously treated with the tumour initiator N-nitroso-N-methyluren by gavage ; and through examining the effects of pure microcystin-LR in cultured primary hepatocytes from immature mice. / Thesis (Ph.D.)--University of Adelaide, Dept. of Clinical and Experimental Pharmacology, 1998?

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 4 uppsatser.

Thesis (MTech. degree: Chemistry) / Trace and ultra-trace levels of platinum group metals (PGMs) in waste effluent pose an increasing risk of exposure to human and aquatic organisms. These metal ions accumulate in environmental matrices such as water, soil and sediments thereby aggravating the situation. In addition, industrial and automotive catalytic emissions of PGMs are increasing worldwide and both mechanical and thermal wear have been found to increase the risk of exposure. Currently, methods for the determination of low levels (μg/L) of PGMs require expensive and sophisticated instrumentation. The objective of this study was to investigate the type of bonding that would lead to preconcentration of low levels of Pt, Pd and Rh ions onto suitable solid phase adsorbents, allowing for the monitoring of their possible presence in river water samples taken downstream of platinum refineries. Preconcentration prior to analysis will enable the metal ions of interest to be determined on a less expensive instrument, such as an Flame Atomic Absorption Spectrometer, Electro Thermal Atomic Absorption Spectrometer, or at most, by use of Inductively Coupled Plasma-Optical Emission Spectrometry. Different solid phase extraction methods were applied including maize tassel, four commercially available resins and two modified resins. Results, particularly for the adsorption of Pt, were excellent with up to twenty two times the original concentration of this metal ion being recovered.

Orientador: Iveraldo dos Santos Dutra / Banca: Flavia Thomaz Verechia Pereira / Banca: Marcia Marinho / Resumo: A preocupação com os problemas ambientais tem se tornando um tema muito abordado. Dentre essas preocupações está aquela associada às degradações da qualidade da água. Essa degradação faz com que ocorra o processo de eutrofização, que é o acúmulo de nutrientes como nitrogênio e fósforo, que causam florações de algas, nas quais as mais conhecidas são as cianobactérias. A presença dessas na água de dessedentação de bovinos pode ter como consequência danos à saúde dos animais. Embora não existem relatos da ocorrência de intoxicações em bovinos no país, cada vez mais se observa a presença de situações de risco no meio pecuário. Portanto, o objetivo do presente estudo foi o de verificar a presença de cianobactérias potencialmente patogênicas em água de dessedentação de bovinos e descrever alguns parâmetros físico-químicos (pH, temperatura e oxigênio dissolvido) nos locais de coleta. As coletas foram feitas em propriedades rurais de munícipios como Brasilândia - MS, Guararapes - SP, Lavínia - SP, Nova Crixás - GO e Aruanã - GO. A água foi coletada com garrafas tipo âmbar, utilizando o reagente lugol para preservação das amostras. As análises foram feitas através de microscópicos óptico. Dentre as amostras, foram encontradas duas cianobactérias produtoras de toxinas nos municípios de Brasilândia e Lavínia, sendo elas as do gênero Merismopedia e Microcystis. Os parâmetros tiveram valores compatíveis para a ocorrência do processo de eutrofização. A presença de cianotoxinas revela a possibilidade de ocorrência de problemas sanitários nos bovinos mantidos em sistemas de produção em que a água de dessedentação esteja contaminada / Abstract: Concern with environmental problems has become a subject much discussed. Among these concerns is that associated with the degradation of water quality. This degradation occurs makes the process of eutrophication, which is the accumulation of nutrients such as nitrogen and phosphorus that cause algal blooms, in which the best known are the cyanobacteria. The presence of these in water watering cattle could result in damage to the health of animals. Although there are no reports of intoxication occurring in cattle in the country, increasingly observed the presence of risk situations among livestock. Therefore, the goal of this study was to verify the presence of potentially pathogenic cyanobacteria in water of watering cattle and describe some physical and chemical parameters (pH, temperature and dissolved oxygen) in the sampling sites. The collections were made on farms in towns like, Brasilândia - MS, Guararapes - SP, Lavínia - SP, Nova Crixás - GO and Aruanã - GO. The water was collected in amber bottles type using lugol reagent for preservation of samples. Analyses were performed using optical microscopy. Among the samples, two were found cyanobacteria produce toxins that the municipalities of Brasilândia and Lavínia, and they are of the genus Microcystis and Merismopedia. The parameters have compatible values for the occurrence of eutrophication process. The presence of cyanotoxins reveals the possibility of health problems in cattle kept in production systems where the water is contaminated watering / Mestre

Made available in DSpace on 2014-06-11T19:27:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-09-01Bitstream added on 2014-06-13T18:55:53Z : No. of bitstreams: 1 silva_ac_me_araca.pdf: 646131 bytes, checksum: d293972f9a5f2f20cce619a757ca0616 (MD5) / A preocupação com os problemas ambientais tem se tornando um tema muito abordado. Dentre essas preocupações está aquela associada às degradações da qualidade da água. Essa degradação faz com que ocorra o processo de eutrofização, que é o acúmulo de nutrientes como nitrogênio e fósforo, que causam florações de algas, nas quais as mais conhecidas são as cianobactérias. A presença dessas na água de dessedentação de bovinos pode ter como consequência danos à saúde dos animais. Embora não existem relatos da ocorrência de intoxicações em bovinos no país, cada vez mais se observa a presença de situações de risco no meio pecuário. Portanto, o objetivo do presente estudo foi o de verificar a presença de cianobactérias potencialmente patogênicas em água de dessedentação de bovinos e descrever alguns parâmetros físico-químicos (pH, temperatura e oxigênio dissolvido) nos locais de coleta. As coletas foram feitas em propriedades rurais de munícipios como Brasilândia – MS, Guararapes – SP, Lavínia – SP, Nova Crixás – GO e Aruanã – GO. A água foi coletada com garrafas tipo âmbar, utilizando o reagente lugol para preservação das amostras. As análises foram feitas através de microscópicos óptico. Dentre as amostras, foram encontradas duas cianobactérias produtoras de toxinas nos municípios de Brasilândia e Lavínia, sendo elas as do gênero Merismopedia e Microcystis. Os parâmetros tiveram valores compatíveis para a ocorrência do processo de eutrofização. A presença de cianotoxinas revela a possibilidade de ocorrência de problemas sanitários nos bovinos mantidos em sistemas de produção em que a água de dessedentação esteja contaminada / Concern with environmental problems has become a subject much discussed. Among these concerns is that associated with the degradation of water quality. This degradation occurs makes the process of eutrophication, which is the accumulation of nutrients such as nitrogen and phosphorus that cause algal blooms, in which the best known are the cyanobacteria. The presence of these in water watering cattle could result in damage to the health of animals. Although there are no reports of intoxication occurring in cattle in the country, increasingly observed the presence of risk situations among livestock. Therefore, the goal of this study was to verify the presence of potentially pathogenic cyanobacteria in water of watering cattle and describe some physical and chemical parameters (pH, temperature and dissolved oxygen) in the sampling sites. The collections were made on farms in towns like, Brasilândia - MS, Guararapes - SP, Lavínia - SP, Nova Crixás – GO and Aruanã - GO. The water was collected in amber bottles type using lugol reagent for preservation of samples. Analyses were performed using optical microscopy. Among the samples, two were found cyanobacteria produce toxins that the municipalities of Brasilândia and Lavínia, and they are of the genus Microcystis and Merismopedia. The parameters have compatible values for the occurrence of eutrophication process. The presence of cyanotoxins reveals the possibility of health problems in cattle kept in production systems where the water is contaminated watering

The analysis of organic pollutants in water is traditionally done following EPA procedures which commonly use liquid-liquid extraction. One liter of water is extracted three times with 60 mL of an organic solvent. The extract is concentrated and analyzed by gas chromatography. This procedure is time consuming and can cause losses of semi-volatile components, in addition to requiring a relatively large amount of organic solvent (180 mL). By performing the extraction directly in a GC autosampler vial using one milliliter of contaminated water and one milliliter of organic solvent, then injecting a large volume (~150 mL) of the organic layer taken directly from the vial by an autosampler, the same analysis can be done simpler, quicker, and with much less organic solvent (1 mL). / Master of Science

Due to the importance of carbohydrates in biological systems, many efforts have been made to develop a quantitative method for analysis of carbohydrates in natural waters. The low concentrations of dissolved sugars in natural waters require a sensitive analytical method. In this study, gas chromatography of alditol acetate derivatives of sugars was investigated for quantitative and qualitative analysis of individual dissolved sugars in natural waters. The alditol acetate derivatives of sugars give only one derivative for each sugar, yielding qualitative and quantitative results. The detection limit was 25 nM for each sugar. Because of this very low detection limit, only 100 ml of sample was required for analysis. From measurements of the alditol acetate derivatives, qualitative and quantitative analysis of pentoses (arabinose and xylose) and hexoses (mannose, galactose, and glucose) were obtained from The Williamson River and its tributaries, which are located near Klamath Falls, Oregon. Total organic carbon concentrations vary greatly in this river system as a result of the river passing through Klamath Marsh, which introduces very high amounts of humic substances into the river system. The range of total concentrations of dissolved sugars is 0.07 to 7.3 μM; the lowest occurring in the spring waters, and the highest in humic-rich waters. Monosaccharide, polysaccharide, and humic-bonded saccharide concentrations, which were obtained from three sample sites, showed very low concentrations of monosaccharides, moderate concentrations of polysaccharides, and moderately high concentrations of humic-bonded saccharides.

The photometric pararosaniline (pRA) method for determination of S(IV) has been adapted to flow injection sample processing (FIA). Prominent features of the method include a limit of detection of 0.010 ppm of dissolved sulfur dioxide and a sampling rate of 20 per hour. The concentration range investigated was 0.010 to 0.200 ppm S02. Sequential samples were collected from two rainstorms and SO2 concentrations were measured for 19 samples. The suppression of interference by Cr(III), Mn(II), and Fe(III) using 1,2-cyclohexylenedinitrilotetraacetic acid (CDTA) and ethylenediaminetetraacetic acid (EDTA) was investigated. A comparison of the adapted FIA method and its parent manual method has shown the FIA method to have the advantages of increased sample throughput, decreased reagent consumption, and increased precision.

This research investigated the relationships between molecular size and the TOC, TTHM, acid strength and color concentrations present in raw and coagulated water from Lake Washington. Three separate coagulants were utilized for investigation. There were: Al, Fe and Mg. Results indicated that the majority of the TOC, color and TTHM precursors were in the colloidal size range and removed by coagulation. The remaining TTHM precursors are mostly molecular and require a process other than coagulation for removal from the potable water before environmental standards are met.

Dissertation submitted in partial compliance with the requirements of the Masters Degree in Technology: Chemistry, in the Faculty of Applied Sciences at the Durban University of Technology, 2008. / In this work, a holistic approach to validate analytical methods was assessed by virtue of Monte Carlo simulations. This approach involves a statement of the methodsâ s scope (i.e. analytes, matrices and concentration levels) and requisites (internal or external); selection of the methodâ s (fit-for-purpose) features; pre-validation and validation of the intermediate accuracy and its assessment by means of Monte Carlo simulations. Validation of the other methodâ s features and a validity statement in terms of a â fit-for-purposeâ decision making, harmonized validation-control-uncertainty statistics and short-term routine work with the aim of proposing virtually â ready-to-useâ methods. The protocol could be transferred to other methods. The main aim is to harmonize the work to be done by research teams and routine laboratories assuming that different aims, strategies and practical viewpoints exist. As a result, the recommended protocol should be seen as a starting point. It is necessary to propose definitive (harmonized) protocols that must be established by international normalisation/accreditation entities. The Quality Assurance (Method verification and Internal Quality Control, IQC) limits, as well as sample uncertainty were estimated consistently with the validated accuracy statistics i.e. E U (E) and RSDi + U (RSDi). Two case studies were used to assess Monte Carlo simulation as a tool for method validation in analytical laboratories, the first involves an indirect polarographic method for determining nitrate in waste water and the second involves a direct determination of heavy metals in sea water by differential pulse anodic stripping voltammetry, as an example of the application of the protocol. In this sense the uncertainty obtained could be used for decision making purposes as it is very tempting to use uncertainty as a commercial argument and in this work it has been shown that the smaller the uncertainty, the better the measurement of the instrument or the laboratoryâ s reputation.