Biosolids are the nutrient-rich organic residual materials resulting from the treatment of domestic sewage at a wastewater treatment facility, and are increasingly land-applied for agricultural and land-reclamation purposes as part of the wastewater management process. While the presence and fate of estrogenic endocrine-disruptors (eEDCs) in wastewater has been extensively studied, much less focus has been given to examining the presence and fate of eEDCs during biosolids treatment. In particular, little work has been done to measure the net estrogenic potency of biosolids using in vitro bioassays, such as the Yeast Estrogen Screen (YES) assay. This is despite the fact that widespread land-application of biosolids provides for the direct introduction of eEDCs into terrestrial and aquatic environments. The relative scarcity of bioassay-based net estrogenicity data for sludges and biosolids is in large part due to the analytical challenges involved in working with such a complex sample matrix. Comprehensive sampling at wastewater treatment plants in Guelph and London, ON, demonstrated that the estrogenicity of anaerobically-treated biosolids is considerably lower (12.0-19.7 ng/g estradiol-equivalents) than that reported in earlier published studies. The results of the present study were made possible due to the development of a sample preparation methodology that overcame the toxic effects that sludge and biosolid samples typically exert on yeast cells in the YES assay. An anti-estrogenicity assay was also applied for the first time to sludges/biosolids to measure the extent to which antagonistic compounds ‘block’ the response of the YES assay. The results of these tests suggest that although the net estrogenicity of anaerobically treated solids is indeed low, up to twice the amount of estrogenicity measured by the YES assay may be masked in biosolids by the presence of antagonistic compounds. While aerobic treatment conditions reduced net estrogenicity to at-or-below detectable levels, net estrogenicity remained relatively constant throughout the unit processes of the anaerobic treatment train. Biosolid ageing during storage led to an overall decrease in net estrogenicity of both conventionally-treated “restricted use” and advanced-treated “unrestricted use” anaerobic biosolids. However, levels of net estrogenicity were observed to spike during the early stages of storage, particularly under freeze/thaw conditions. / Natural Science and Engineering Research Council of Canada (NSERC) PGS-D3 scholarship, Water Environment Association of Ontario, Canadian Water Network

Stability plays an important role in the development of a new drug product. High Performance Liquid Chromatography (HPLC) is considered a stability indicating method of analysis. It is widely used in the pharmaceutical industry for the quantification of small organic molecules during stability testing. Previous stability studies conducted on Pheroid™-based drug products, experienced problems with the generation of reliable data by means of HPLC analysis. With these studies it was concluded that the inconclusive results could either be attributed to the stability of the delivery system itself and the compatibility of the active pharmaceutical ingredients (API's) with the delivery system, or to the usage of unsuitable HPLC methods. The aims of this study were to: i. determine if the Pheroid™ delivery system changes significantly over time at accelerated storage conditions and how these changes influence the HPLC analysis, ii. determine the effect of the anti-oxidant tert-butylhydroquinone (TBHQ) on the stability and HPLC analysis of the Pheroid™ delivery system, and iii. to suggest a suitable approach for the analysis of Pheroid™-based drug products. Pheroid™ microsponges, containing no API's, were prepared and stored for a period of three months at 5°C, 25°C+60%RH, 30°C+65%RH and 40°C+75%RH. Two of the four Pheroid™ formulations contained an extra anti-oxidant, namely TBHQ. Monthly HPLC analyses were done using existing methods for mefloquine and artesunate. In addition to HPLC analysis, particle size analysis and Confocal Laser Scanning Microscopy (CLSM) were undertaken to support the HPLC results and provide information concerning the overall stability of the Pheroid™ delivery system. After the completion of the above analyses, experiments were carried out to determine whether adjustments to some of the key chromatographic parameters could improve the separation of Pheroid™-based samples. The parameters that were subjected to change included the organic solvent, isocratic versus gradient separation, pH and detection wavelength. Two pro-Pheroid vesicles formulations were prepared and stored for a three month period at 40°C+75%RH only. No API was added to the one formulation while the other contained 2 mg/ml of mefloquine hydrochloride. Results obtained indicated that the Pheroid™ formulations changed after exposure to elevated temperature and humidity. The number of detectable peaks increased, longer run times became necessary and solubility in the sample solvent (methanol) decreased. Solubility of the Pheroid™ formulations in methanol was preserved to some extent by the presence of TBHQ. Physical signs of instability like discolouration and creaming were noted for TBHQ-containing formulations. TBHQ also seemed to have influenced the particle sizes, particle size distributions and structure of the Pheroid™ microsponges. With adjustments made to the HPLC method it was found that: i. the sample solvent is incompatible with the HPLC system, ii. very hydrophobic compounds are present in the Pheroid™-based samples, iii. acetontrile and methanol are unsuitable for both gradient and isocratic separation of Pheroid™-based samples, iv. more Pheroid™ components absorb at shorter wavelengths, and v. small changes in the pH values usually implemented do not influence the retention and selectivity of the Pheroid™ components. The Pheroid™ delivery system proved to be too complex and reversed hydrophobic for phase HPLC analysis. Preparation of the sample by only diluting the Pheroid™ formulations with pure methanol was not optimal. These samples introduced compounds to the column of which some caused interferences with the analyte peak while others were difficult to elute from the column. To continue using HPLC for the analysis of Pheroid™-based drug products, it is therefore recommended that attention should be given to the development of a more appropriate sample preparation procedure, like solid phase extraction or liquid-liquid extraction, one that will eliminate the effects of the Pheroid™ components. Physical instabilities noticed with the addition of TBHQ, suggest that there should also be attended to the compatibility and stability of each of the components in the Pheroid™ delivery system during formulation development. / Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2010.

Stability plays an important role in the development of a new drug product. High Performance Liquid Chromatography (HPLC) is considered a stability indicating method of analysis. It is widely used in the pharmaceutical industry for the quantification of small organic molecules during stability testing. Previous stability studies conducted on Pheroid™-based drug products, experienced problems with the generation of reliable data by means of HPLC analysis. With these studies it was concluded that the inconclusive results could either be attributed to the stability of the delivery system itself and the compatibility of the active pharmaceutical ingredients (API's) with the delivery system, or to the usage of unsuitable HPLC methods. The aims of this study were to: i. determine if the Pheroid™ delivery system changes significantly over time at accelerated storage conditions and how these changes influence the HPLC analysis, ii. determine the effect of the anti-oxidant tert-butylhydroquinone (TBHQ) on the stability and HPLC analysis of the Pheroid™ delivery system, and iii. to suggest a suitable approach for the analysis of Pheroid™-based drug products. Pheroid™ microsponges, containing no API's, were prepared and stored for a period of three months at 5°C, 25°C+60%RH, 30°C+65%RH and 40°C+75%RH. Two of the four Pheroid™ formulations contained an extra anti-oxidant, namely TBHQ. Monthly HPLC analyses were done using existing methods for mefloquine and artesunate. In addition to HPLC analysis, particle size analysis and Confocal Laser Scanning Microscopy (CLSM) were undertaken to support the HPLC results and provide information concerning the overall stability of the Pheroid™ delivery system. After the completion of the above analyses, experiments were carried out to determine whether adjustments to some of the key chromatographic parameters could improve the separation of Pheroid™-based samples. The parameters that were subjected to change included the organic solvent, isocratic versus gradient separation, pH and detection wavelength. Two pro-Pheroid vesicles formulations were prepared and stored for a three month period at 40°C+75%RH only. No API was added to the one formulation while the other contained 2 mg/ml of mefloquine hydrochloride. Results obtained indicated that the Pheroid™ formulations changed after exposure to elevated temperature and humidity. The number of detectable peaks increased, longer run times became necessary and solubility in the sample solvent (methanol) decreased. Solubility of the Pheroid™ formulations in methanol was preserved to some extent by the presence of TBHQ. Physical signs of instability like discolouration and creaming were noted for TBHQ-containing formulations. TBHQ also seemed to have influenced the particle sizes, particle size distributions and structure of the Pheroid™ microsponges. With adjustments made to the HPLC method it was found that: i. the sample solvent is incompatible with the HPLC system, ii. very hydrophobic compounds are present in the Pheroid™-based samples, iii. acetontrile and methanol are unsuitable for both gradient and isocratic separation of Pheroid™-based samples, iv. more Pheroid™ components absorb at shorter wavelengths, and v. small changes in the pH values usually implemented do not influence the retention and selectivity of the Pheroid™ components. The Pheroid™ delivery system proved to be too complex and reversed hydrophobic for phase HPLC analysis. Preparation of the sample by only diluting the Pheroid™ formulations with pure methanol was not optimal. These samples introduced compounds to the column of which some caused interferences with the analyte peak while others were difficult to elute from the column. To continue using HPLC for the analysis of Pheroid™-based drug products, it is therefore recommended that attention should be given to the development of a more appropriate sample preparation procedure, like solid phase extraction or liquid-liquid extraction, one that will eliminate the effects of the Pheroid™ components. Physical instabilities noticed with the addition of TBHQ, suggest that there should also be attended to the compatibility and stability of each of the components in the Pheroid™ delivery system during formulation development. / Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2010.

<p><bold>Background</bold> The diagnosis of sepsis is challenging because the infection can be caused by more than 50 species of pathogens that might exist in the bloodstream in very low concentrations, e.g., less than 1 colony-forming unit/ml. As a result, among the current sepsis diagnostic methods there is an unsatisfactory trade-off between the assay time and the specificity of the derived diagnostic information. Although the present qPCR-based test is more specific than biomarker detection and faster than culturing, its 6 ~ 10 hr turnaround remains suboptimal relative to the 7.6%/hr rapid deterioration of the survival rate, and the 3 hr hands-on time is labor-intensive. To address these issues, this work aims to utilize the advances in microfluidic technologies to expedite and automate the ``nucleic acid purification - qPCR sequence detection'' workflow.</p><p><bold>Methods and Results</bold> This task is evaluated to be best approached by combining immiscible phase filtration (IPF) and digital microfluidic droplet actuation (DM) on a fluidic device. In IPF, as nucleic acid-bound magnetic beads are transported from an aqueous phase to an immiscible phase, the carryover of aqueous contaminants is minimized by the high interfacial tension. Thus, unlike a conventional bead-based assay, the necessary degree of purification can be attained in a few wash steps. After IPF reduces the sample volume from a milliliter-sized lysate to a microliter-sized eluent, DM can be used to automatically prepare the PCR mixture. This begins with compartmenting the eluent in accordance with the desired number of multiplex qPCR reactions, and then transporting droplets of the PCR reagents to mix with the eluent droplets. Under the outlined approach, the IPF - DM integration should lead to a notably reduced turnaround and a hands-free ``lysate-to-answer'' operation.</p><p>As the first step towards such a diagnostic device, the primary objective of this thesis is to verify the feasibility of the IPF - DM integration. This is achieved in four phases. First, the suitable assays, fluidic device, and auxiliary systems are developed. Second, the extent of purification obtained per IPF wash, and hence the number of washes needed for uninhibited qPCR, are estimated via off-chip UV absorbance measurement and on-chip qPCR. Third, the performance of on-chip qPCR, particularly the copy number - threshold cycle correlation, is characterized. Lastly, the above developments accumulate to an experiment that includes the following on-chip steps: DNA purification by IPF, PCR mixture preparation via DM, and target quantification using qPCR - thereby demonstrating the core procedures in the proposed approach.</p><p><bold>Conclusions</bold> It is proposed to expedite and automate qPCR-based multiplex sparse pathogen detection by combining IPF and DM on a fluidic device. As a start, this work demonstrated the feasibility of the IPF - DM integration. However, a more thermally robust device structure will be needed for later quantitative investigations, e.g., improving the bead - buffer mixing. Importantly, evidences indicate that future iterations of the IPF - DM fluidic device could reduce the sample-to-answer time by 75% to 1.5 hr and decrease the hands-on time by 90% to approximately 20 min.</p> / Dissertation

The initial research of this thesis involves the evaluation of different strategies for developing diverse chemistries of highly stable coatings for the automated 96-blade (thin-film) solid phase microextraction (SPME) system. Thin-film geometry increases the volume of extractive phase, and consequently improves the sensitivity of the analysis. Sol-gel technology was used for the preparation of octadecyl (C18)-silica gel thin-film coating. The evaluation of the C18-silica gel SPME extractive phase resulted in stable physical and chemical characteristics and long-term reusability with a high degree of reproducibility. Biocompatible polyacrylonitrile (PAN) polymer was used for the preparation of particle-based extractive phases in order to improve the biocompatible characteristics of SPME coatings for the extraction from biological samples. Three different immobilization strategies were evaluated for developing highly stable coatings for the automated 96-blade SPME system. The spraying was found to be the optimal method in terms of stability and reusability for long-term use. The optimized C18-PAN coating demonstrated improved biocompatibility, stability, and reusability for the extraction of benzodiazepines from human plasma in comparison with those of C18-silica gel coating. To improve the biocompatible properties of the C18-PAN SPME coating for long-term direct analysis from whole blood, different modification strategies were studied and evaluated. The modification of the coating with an extra layer of biocompatible polyacrylonitrile resulted in significant improvement in the blood compatibility in long-term use. ‘Extracted blood spot’ (EBS) sampling was introduced as a novel approach to overcome the limitations of dried blood spot sampling. EBS includes the application of a biocompatible SPME coating for spot sampling of blood or other biofluids. The compatibility of EBS sampling with different analytical methods was demonstrated. The utilization of EBS as a fast sampling and sample preparation method resulted in a significant reduction of matrix effects through efficient sample clean-up. Modified polystyrene-divinylbenzene (PS-DVB)-PAN and phenylboronic acid (PBA)-PAN 96-blade SPME coatings were developed and evaluated for the extraction of analytes in a wide range of polarity. These coatings demonstrated efficient extraction recovery for both polar and non-polar groups of compounds, and presented chemical and mechanical stabilities and reproducible extraction efficiencies for more than 100 usages in biological sample.

Made available in DSpace on 2014-10-09T12:28:37Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:29Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Made available in DSpace on 2014-10-09T12:48:43Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:45Z (GMT). No. of bitstreams: 1 09248.pdf: 4025394 bytes, checksum: 8a35726844a12943f94f0d0003f7b6fc (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP / FAPESP:00/04423-3

Submitted by MAISA CRISTINA LAZARO null (maisalazaro_mcl@hotmail.com) on 2017-09-05T15:09:44Z No. of bitstreams: 1 Dissertação Mestrado_Repositório.pdf: 1448238 bytes, checksum: f02ad2ea0e02cac8044c4645b5fd43f7 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-09-06T16:16:31Z (GMT) No. of bitstreams: 2 lazaro_mc_me_araiq_par.pdf: 540678 bytes, checksum: 2e6053c1e59ea8b435722b01fd52317a (MD5) lazaro_mc_me_araiq_int.pdf: 1448238 bytes, checksum: f02ad2ea0e02cac8044c4645b5fd43f7 (MD5) / Made available in DSpace on 2017-09-06T16:16:31Z (GMT). No. of bitstreams: 2 lazaro_mc_me_araiq_par.pdf: 540678 bytes, checksum: 2e6053c1e59ea8b435722b01fd52317a (MD5) lazaro_mc_me_araiq_int.pdf: 1448238 bytes, checksum: f02ad2ea0e02cac8044c4645b5fd43f7 (MD5) Previous issue date: 2017-08-09 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A espectrometria de emissão óptica em plasma induzido por laser (LIBS) é uma técnica que vem se desenvolvendo cada vez mais para determinações analíticas multielementares, com aplicações em diversas áreas. Possui várias vantagens, como por exemplo, ser uma técnica de análise rápida, minimamente destrutiva e ambientalmente amigável, enquanto que a maior dificuldade está baseada na sua relativa baixa sensibilidade. Muitos estudos têm sido desenvolvidos com a finalidade de melhorar a sensibilidade, porém os aprimoramentos elaborados demandam equipamentos mais sofisticados, aumentando o custo e comprometendo a portabilidade da técnica. O presente trabalho avaliou estratégias simples para melhorar a sensibilidade das medidas em LIBS, permitindo o uso de instrumentos compactos de pulso simples. As estratégias desenvolvidas se baseiam na proposição da introdução de uma etapa simples de pré-tratamento da amostra, capaz de agir na fragilização de estruturas químicas que por consequência levem ao aumento das intensidades de emissão das espécies componentes da amostra. As etapas de pré-tratamentos buscam em sua essencialidade não descaracterizar as vantagens analíticas de LIBS, tais como a simplicidade e a não utilização de reagentes potencialmente tóxicos, além de serem aplicáveis à diversos tipos de amostras. A ação da temperatura sobre a modificação de estruturas químicas foi avaliada utilizando aquecimento em mufla para amostra de material vegetal, solo e liga metálica e em forno de micro-ondas para amostra vegetal. Os tratamentos empregados utilizando aquecimento em mufla resultaram em aumentos nas intensidades de emissão em toda região espectral para todas as amostras avaliadas; para a amostra de folha, material para o qual foram obtidos os melhores resultados, foram verificados aumentos de 47x com relação à área de pico da linha de Ca I em 612,14 nm, além do aparecimento de linhas antes não observadas, como a de Sr II em 407,82 nm. Para a amostra de liga, a área da linha de Fe I em 489,22 nm teve um aumento de 8x e para a amostra de solo, a linha de Na em 588,89 nm, por exemplo, teve seu valor de área aumentado em 4x com a aplicação do tratamento térmico. O aquecimento em micro-ondas forneceu incrementos de intensidade menos pronunciados, comparados ao aquecimento em mufla. Adicionalmente foi avaliada a introdução de fundente à amostra de solo com o intuito de melhorar processos físicos, os quais poderiam culminar em aumento dos processos de emissão dos analitos da amostra, entretanto, esta estratégia não atingiu o objetivo proposto. Por fim, o tratamento térmico em mufla foi aplicado no desenvolvimento de um método para determinação de Sr em material foliar utilizando LIBS. O método desenvolvido apresentou curva analítica linear com coeficiente de correlação igual a 0,997, limite de detecção igual a 4,23 mg kg-1 e limite de quantificação igual a 14,09 mg kg-1. A análise de material de referência certificado foliar pelo método proposto indicou que a concentração de Sr determinada é concordante com o valor certificado a 95% de confiança (test t pareado). / Laser-induced breakdown spectroscopy (LIBS) is an analytical technique in development, increasingly applied for multielemental determinations in several areas. It shows several advantages, such as rapidity, minimally destructive and environmentally friendly, although the greatest difficulty is based on its relatively low sensitivity. Many efforts have been expended to improve LIBS sensitivity, but several proposals require more sophisticated equipment, increasing the cost and compromising the portability of the technique. The present work evaluated simple strategies to improve the sensitivity of LIBS measurements allowing the use of compact single pulse instruments. The proposed strategies are based on a simple sample pretreatment, able to promotes simplification of chemical structures, which could lead to an increase of emission intensities. The proposed pretreatment steps aimed to preserve the interesting LIBS analytical advantages, such as its simplicity and non-use of toxic reagents, and its applicability to several types of samples. Then the temperature action on the simplification of chemical structures was evaluated using conventional muffle oven, for samples of plant leaves, soil and metal alloy. Additionally, microwave oven heating was evaluated for plant leaves. The muffle oven treatments resulted in important increases of the emission intensities for all spectral region of all evaluated samples; for the plant leaves, material for which the best results were observed, the integrated peak area of the Ca I line at 612.14 nm was increased about 47x after the thermic treatment. Moreover, new emission lines, not observed before, such as Sr II line at 407.82 nm, appeared. In the alloy sample, the integrated area of Fe I line at 489.22 nm showed an increase of 8x and in soil sample the Na I line at 588.89 nm, showed an increasing of 4x. The microwave heating provided less pronounced intensity increments compared to the muffle heating. The mixture of the soil sample with chemical modifier was also evaluated in order to improve physical processes, which could lead to an increasing of the emission signals. Nevertheless, this strategy did not reach the expected. Finally, the heat treatment in muffle was applied in the development of a method for determination of Sr in leaf material using LIBS. The developed method presented a linear analytical curve with correlation coefficient of 0.997, limit of detection of 4.23 mg kg -1 and limit of quantification of 14.09 mg kg-1 . Analysis of leaf reference material by the proposed method indicated the determined concentration of Sr is in agreement with the certified value at 95% confidence (paired t-test). / CNPq: 830856/1999-4

Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2016-09-12T17:29:38Z No. of bitstreams: 1 Dissertação José Tiago Pereira Barbosa.pdf: 1750358 bytes, checksum: e01d971ee45a1ab67fd25d7981b87383 (MD5) / Approved for entry into archive by NUBIA OLIVEIRA (nubia.marilia@ufba.br) on 2016-09-12T18:21:30Z (GMT) No. of bitstreams: 1 Dissertação José Tiago Pereira Barbosa.pdf: 1750358 bytes, checksum: e01d971ee45a1ab67fd25d7981b87383 (MD5) / Made available in DSpace on 2016-09-12T18:21:31Z (GMT). No. of bitstreams: 1 Dissertação José Tiago Pereira Barbosa.pdf: 1750358 bytes, checksum: e01d971ee45a1ab67fd25d7981b87383 (MD5) / CAPEs / A proteína texturizada de soja possui alto conteúdo protéico e é usualmente utilizada como alternativa na substituição de uma porção de carne. O objetivo deste trabalho foi avaliar três procedimentos de decomposição úmida, visando determinação multielementar (Ca, K, Mg, P, Cr, Cu, Fe, Mn, Ni e Zn) em amostras de proteína texturizada de soja por espectrometria de emissão óptica com plasma indutivamente acoplado (ICP OES). Nos procedimentos usando chapa aquecedora (PC) e bloco digestor (PB) foi utilizada a mistura de HNO3 e H2O2, enquanto que para o procedimento com forno de microondas focalizadas (PF) foi necessária a introdução também de H2SO4. As figuras analíticas de mérito, tais como precisão, limites de detecção (LOD) e quantificação (LOQ) e efeito de matriz, foram avaliadas para os procedimentos propostos. As concentrações de Al, Cd, Co e Pb, encontraram-se abaixo do LOQ dos procedimentos para as amostras. A exatidão foi verificada com material de referência certificado e por comparação com método de referência da AOAC. Além disso, foi otimizado um sistema miniaturizado de análise por injeção em fluxo visando a determinação de ferro nos digeridos com o reagente 1,10- fenantrolina e os resultados foram concordantes com o método de referência. / The texturized soy protein is a good source of protein and is usually used as an alternative to meat. The aim of this study was the evaluation of three wet decomposition procedures for multi-element analytical determination (Ca, K, Mg, P, Cr, Cu, Fe, Mn, Ni e Zn) in texturized soy protein samples using inductively coupled plasma optical emission spectrometry (ICP OES). In procedures using hot plate (PC) and heating block (PB), a mixture of HNO3 and H2O2 was used, whereas for decomposition in a focused-microwave-oven (PF), the use of H2SO4 was necessary. The analytical figures of merit of the developed analytical procedures such as precision, accuracy and matrix effect, were statistically assessed. The concentrations of Al, Cd, Co and Pb were found below oh the LOQ. The accuracy of the results was demonstrated using one certified reference material (spinach leaves NIST 1570a) and comparison with recommended AOAC official method. Moreover, a flow injection analysis microsystem for determination of iron with 1,10-phenantroline was optimized and the results were concordant with those obtained with the reference method.

94 f. / Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2013-04-08T14:08:02Z No. of bitstreams: 1 Dissertação_Milena Pinelli Versão CD.pdf: 8574876 bytes, checksum: f2c4d5fb3dab22669ba4ef48a90fa8a1 (MD5) / Approved for entry into archive by Ana Hilda Fonseca(anahilda@ufba.br) on 2013-06-06T15:15:34Z (GMT) No. of bitstreams: 1 Dissertação_Milena Pinelli Versão CD.pdf: 8574876 bytes, checksum: f2c4d5fb3dab22669ba4ef48a90fa8a1 (MD5) / Made available in DSpace on 2013-06-06T15:15:34Z (GMT). No. of bitstreams: 1 Dissertação_Milena Pinelli Versão CD.pdf: 8574876 bytes, checksum: f2c4d5fb3dab22669ba4ef48a90fa8a1 (MD5) Previous issue date: 2012 / CAPES / Os metais têm origem natural como componentes das rochas e nesta situação não apresentam riscos aos seres vivos. Atualmente existem poucos estudos relacionados à obtenção de valores de referência para concentrações naturais de metais em solos do Brasil, o que dificulta a ação dos órgãos fiscalizadores e algumas instituições em monitorarem os ambientes que podem ter sido contaminados por indústrias ou outros tipos de empreendimentos. Este trabalho teve como objetivo propor valores de referência para concentração dos metais Cd, Co, Cr, Cu, Pb, Mn, Ni e Zn em solo do entorno na Baía do Iguape. As amostras foram digeridas em forno de micro-ondas com cavidade utilizando o procedimento da Agência de Proteção Ambiental, EPA 3051A e para as determinações dos analitos foi empregada a espectrometria de emissão óptica com plasma indutivamente acoplado (ICP OES). As linhas de emissão selecionadas foram, em nm: Cd II 226,502; Co II 228,615 nm; Cr II 267,716; Cu Il 213,598; Mn II 257,610; Ni II 216,555; Pb II 220,353; e Zn I 213,857. A validação foi feita avaliando-se os limites de detecção (LOD) e de quantificação (LOQ), a faixa linear de trabalho, precisão, análise de material de referência certificado e testes de adição e recuperação. O procedimento validado foi aplicado na caracterização dos solos formados a partir de sedimentos da Formação Barreiras, Arenito e Folhelho, quanto às concentrações dos analitos Cd, Co, Cu, Cr, Mn, Ni, Pb e Zn no entorno da Baía de Iguape. As faixas de concentrações obtidas para as áreas estudadas foram, em mg kg-1: Barreiras encosta: Cd (0,57 - 1,7), Co (4,5 - 5,7), Cr (33 - 73), Cu (7,0 - 16), Mn (74 - 123), Ni (5,0 - 13), Pb (4,8 - 16) e Zn (12 - 30); Barreiras plana: Cd (0,20 - 0,67), Co (1,3 - 2,2), Cr (23 - 48), Cu (3,2 - 4,8), Mn (46 - 56), Ni (4,2 - 12), Pb (2,5 - 8,3) e Zn (12 - 24); Arenito 1 Cd (0,12 - 0,43), Co (0,30 - 0,90), Cr (4,9 - 14), Cu (1,7- 4,1), Mn (12 - 30), Ni (1,2 - 3,7), Pb (2,7 - 7,5) e Zn (1,8 - 8,6); Arenito 2 : Co (0,7- 2,0), Cr (5,6 - 19,8), Cu (1,7 - 3,1), Mn (10 - 28), Ni (1,9 - 4,0), Pb (1,7 - 4,4) e Zn (1,7 - 6,5); Arenito 3 Cd (0,10 - 0,23), Co (0,40 - 1,5), Cr (2,9 - 12), Cu (1,2 - 4,5), Mn (15 - 31), Ni (1,0 - 4,0), Pb (2,6 - 6,6) e Zn (2,1 - 7,3); Folhelho Cd (0,32 - 1,1), Co (0,92 - 1,7), Cr (37 - 63), Cu (3,6 - 7,2), Mn (27 - 39), Ni (4,4 - 9,3), Pb (3,2 - 11) e Zn (10 - 18). De um modo geral as concentrações obtidas variaram na seguinte ordem decrescente Barreiras> Folhelho> Arenito. Para propor valores de referência para solos com características similares aos analisados, foram selecionadas as áreas Barreira encosta e Arenito 3 e aplicou-se a correlação linear de Pearson e análise de componentes principais (PCA), para selecionar quais parâmetros (metais e atributos) contribuem de forma efetiva para a elaboração das equações do modelo estatístico. As concentrações das amostras foram estimadas de forma satisfatória com as equações elaboradas. Para os solos de Barreiras encosta apenas Co e Pb não apresentaram valores confiáveis de predição enquanto que para o Arenito 3, somente Ni não apresentou resultados confiáveis, devido ao seu baixo coeficiente de determinação. / Salvador