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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.
481

EPR investigation of free radicals in excised and attached leaves subjected to ozone and sulphur dioxide air pollution

Vaartnou, Manivalde January 1988 (has links)
The X-band EPR spectrometry system was modified to allow for the in situ monitoring of free radical changes in attached, intact plant leaves, which were caused by stress factors such as exposure to excessive photon flux density, ozone or sulphur dioxide. This was done through use of the dewar insert of the variable temperature accessory as a guide, the construction of 'T' shaped cellulose acetate holders to which leaves could be attached with adhesive tape, and modification of the gas flow system used for controlled temperature studies. Kinetic studies of free radical formation were possible with leaves which had minimal underlying Fe⁺⁺ and Mn⁺⁺ signals. In leaves with large underlying signals a Varian software program was used to subtract overlapping signals from each other, thereby revealing the free-radical signal changes which occurred under different light regimes and stress conditions. Preliminary investigation disclosed the formation of a new signal upon prolonged exposure to far-red light and the effect of oxygen depletion upon photosynthetic Signals I and II. Leaves subject to high photon flux density reveal an unreported free-radical signal, which decays upon exposure to microwave radiation; and concomitant damage to Photosystems I and II. Upon elimination of this signal leaves return to the undamaged state or reveal permanent damage to either photo-system, depending upon the degree of damage. Kentucky bluegrass and perennial ryegrass leaves subject to low levels of ozone (up to 80ppb) for periods of 8 hours show no changes in free-radical signal formation. At intermediate levels of ozone (80-250ppb) a new free-radical signal was formed within 3 hours of fumigation, Signal II was decreased and Signal I decayed. These changes were reversible if fumigation was terminated. At fumigation levels exceeding 250ppb a different new irreversible free-radical signal was formed in darkness within 1.5 hours of fumigation. Radish, Kentucky bluegrass and perennial ryegrass leaves subject to high levels of sulphur dioxide (10-500ppm) reveal the formation of Signal I upon irradiation with broad-band white or 650nm light, thereby indicating an interruption of normal electron flow from PSII to PSI. Damage to the oxygen-evolving complex and reaction centre of PSII is also revealed through changes in Signal II and the Mn⁺⁺ signal. These changes in the normal EPR signals are dose-dependent. Leaves subject to low levels of sulphur dioxide (600-2000ppb) reveal the disappearance of Signal I after 3 hours of fumigation and the formation of a new free-radical signal with parameters similar to the sulphur trioxide free-radical signal. These latter changes are partially reversible upon termination of fumigation. After prolonged exposure to either ozone or sulphur dioxid a free-radical signal with parameters similar to the superoxid anion free-radical signal is formed in plant leaves. / Land and Food Systems, Faculty of / Graduate
482

Réponses physiologiques, antioxydantes et métabolomiques de Thellungiella salsuginea et Arabidopsis thaliana à l'interaction salinité modérée-phénanthrène : application à la phytoremédiation des HAPs par les halophytes / Physiological, antioxidant and metabolomic responses of Thellungiella salsuginea and Arabidopsis thaliana to moderate salinity-phenanthrene interaction : application to phytoremediation of PAHs by halophytes

Moez, Shiri 04 July 2014 (has links)
La pollution environnementale constitue un problème majeur pour les écosystèmes naturels et la santé publique. Récemment, la phytoremédiation a émergé comme une stratégie innovante, écologique et à faible coût. Elle consiste à utiliser les capacités des plantes à stocker ou/et à dégrader les polluants. Dans cette étude, des analyses physiologiques, biochimiques et métabolomiques, ont permis de montrer que les halophytes, une catégorie des plantes extrêmophiles, présentent une grande capacité à remédier la pollution engendrée par les Hydrocarbures Aromatiques Polycycliques (HAPs). D'autre part, la salinité modérée améliore leur capacité phytoremédiatrice. Ces résultats apportent de nouvelles données pouvant contribuer à l'amélioration de cette stratégie. / Halopytes, plants naturally adapted to high salt concentrations, have no clear definition, yet. Their cross-tolerance to abiotic stresses was reviewed in this work at the physiological, biochemical, and molecular levels, with a special emphasis on the mechanisms involved in their cross-tolerance to salinity and organic pollutants that could allow them a higher potential of xenobiotic phytoremediation as compared to glycophytes. In our experimental part, we compared in a first step some physiological and antioxidant responses to phenanthrene as well as its accumulation in the two related model plants Arabidopsis thaliana (glycophyte) and Thellungiella salsuginea (halophyte).In a second step, we investigated the effects of moderate salinity on the responses of the two species to phenanthrene considered as model Polycyclic Aromatic Hydrocarbon (PAH) molecule. Obtained results showed an improvement of phenanthrene-induced responses in the two plants, the effect being more marked in the halophyte. This observation was particularly related to higher antioxidant activities and the induction of more adapted metabolism as several accumulated metabolites are known to be involved in signaling and osmotic adjustment processes. In a final step, we studied the potential of the halophyte Cakile maritima to remediate an inert sand (to avoid the degradation of the pollutant by microorganisms or their interaction with the plant) highly contaminated with phenanthrene.
483

Impact des polluants d'origine anthropique sur l'olfaction d'un insecte ravageur, Spodoptera littoralis / Impact of anthropogenic pollutants on olfaction in a pest insect, Spodoptera littoralis

Pottier, Marie-Anne 23 June 2014 (has links)
De nombreux comportements assurant la survie des insectes dépendent de l’olfaction. Comprendre comment les polluants peuvent modifier cette modalité sensorielle chez des espèces cibles (ravageurs…) et non-cibles (pollinisateurs…) et quels sont les moyens de réponse dont dispose le système olfactif est donc crucial. J’ai étudié l’impact du cadmium à doses sublétales sur l’olfaction du lépidoptère ravageur modèle Spodoptera littoralis. Sa distribution dans l’organisme, dont les antennes, a été établie puis son impact sur les capacités olfactives des chenilles et des adultes a été analysé par analyse comportementale et électrophysiologique. J’ai montré une diminution de la détection phéromonale chez les adultes mâles et du comportement attractif des chenilles vers une source de nourriture.J’ai caractérisé diverses enzymes de détoxification et protéines de choc thermique antennaires comme biomarqueurs potentiels aux polluants et révélé ainsi une diversité insoupçonnée de ces protéines dans l’antenne. Ces acteurs pourraient être impliqués dans le maintien du fonctionnement du système olfactif en participant à la clearance des xénobiotiques. Parallèlement, j’ai participé à l’étude des effets de la deltaméthrine sur l’olfaction et montré que l’application topique antennaire de doses sublétales de cet insecticide a un impact sur le système olfactif des mâles, et ce du gène au comportement.L’ensemble de nos données montrent que l’organe olfactif bien que très spécialisé, est un organe capable de développer une réponse complexe lors d’un stress xénobiotique. / Many behaviors ensuring the survival of insects depend on olfaction. Understanding how pollutants may alter this sensory modality in target (pests…) and non-targets (pollinators…) species and how the olfactory system could respond to this stress is therefore crucial. I have first studied the impact of sublethal doses of cadmium on olfaction in Spodoptera littoralis, a pest moth model. Cadmium distribution through the insect body, including antennae, has been established and its effect on the olfactory abilities of caterpillars and adults was analyzed by behavioral and electrophysiological approaches. I have showed both a decrease in pheromone detection in adult males and in the attractive behavior of caterpillars to a food source. Moreover, I have characterized various detoxification enzymes and heat shock proteins as potential antennal biomarkers for pollutant exposure and thus revealed an unsuspected diversity of these proteins in the antenna. These actors could be involved in maintaining the functioning of the olfactory system by participating in the clearance of xenobiotics. Meanwhile, I have participated in a study on the effects of deltamethrin on olfaction and showed that topical application of sublethal doses of this insecticide on antenna has an impact on the olfactory system of males, an approach from the gene to the behavior. All our data showed that although highly specialized, the olfactory organ is able to develop a complex response when challenged by a xenobiotic stress.
484

Metal bioaccumulation and biomarker responses in tigerfish, Hydrocynus vittatus, from three South African populations

Fisher, Eve Mariel 07 June 2012 (has links)
M.Sc. / Pollutants present in minute concentrations in aquatic environments and which possess long residence times may be accumulated by aquatic organism such as fish, resulting in adverse affects. Bioaccumulation and biomarker responses are often used to qualify and quantify pollutant exposure and effect, and for this reason form a major part of many environmental assessments. To interpret bioaccumulation and biomarker responses the physico-chemical parameters of the environment should be known. This study aimed to spatially and temporally assess the environmental partitioning of heavy metals in three South African freshwater systems, namely the Pongolapoort Dam, Olifants and Luvuvhu Rivers, and to relate these concentrations to bioaccumulation and biomarker responses in tigerfish, Hydrocynus vittatus. This is because there is relatively little known about the bioaccumulation potential and stress responses of tigerfish to pollutants and they have recently become listed as a protected species. Result from this study showed that there were few differences between seasons in terms of metal bioaccumulation in the Pongolapoort Dam with the exception of Se, Zn and Fe. Selenium and Fe concentrations were linked to concentrations found in the environment, whereas Zn was attributed to a disruption in homeostasis within the fish. Increases in MT were found during the winter months and were attributed to increased metal concentrations at this time, namely Zn and Se, whereas decreases in CEA and PC were observed at this time and were linked to depleted energy reserves, stress and a reduction in the presence of pesticides as a result of decreased runoff during the winter months. It was found in the Olifants and Luvuvhu Rivers that there were no distinct decreases in metal concentrations as the rivers flowed through the KNP, and processes such as rainfall, remobilization of sediments, distance of the study area from the source and geology played a great role in the distribution of metals. Metal concentrations in the Olifants River water, sediment and fish were, for the most part, found to be lower than previous studies, possibly due to improvement in management strategies or increased buffering of this river. Only Al and As were significantly higher in tigerfish from the Olifants River, and this was reflected in high MT concentrations. It was suggested that tigerfish from the Olifants River have developed effective mechanisms for the excretion and detoxification of heavy metals that they are exposed to as a result of extended exposure. Concentrations of AChE were also significantly inhibited in tigerfish from the Olifants River which is indicative of greater concentrations of organophosphates and carbamate pesticides than the other sites. Tigerfish from the Pongolapoort Dam had signifcantly higher levels of MT and significantly inhibited concentrations of AChE in comparison to tigerfish from the Luvuvhu River. The tigerfish from the Luvuvhu River had significantly higher concentrations of Se in muscle tissue. Tigerfish from the Luvuvhu River, also experienced stress as a result of pollution as was apparent from significantly depleted energy reserves in comparison to the other sites under study, and higher concentrations of PC and CYP1A which are typical biomarkers responding to halogenated and aromatic pesticides, such as deltamethrin and endosulfan. It was recommended that further studies be done to assess the presence of pesticides within these systems to determine the contribution of these pollutants to the state of tigerfish
485

Die effek van myn-, nywerheids- en rioolafloopwaters op die waterkwaliteit van die Elsburgspruit, Germiston met spesiale verwysing na die voorkoms en akkumulering van geselekteerde swaarmetale in die ekosisteem

Van der Merwe, Christiaan Gideon 18 February 2014 (has links)
Ph.D. / An investigation was made into the physical, chemical and biological conditions of the Elsburgspruit to establish the extent and quality of pollution over a period of two and a half years from January 1987 June 1989. The results obtained during the investigation can be summarised as follows. Serious faecal pollution as reflected by faecal coliforms, faecal streptococci and coliphage organisms occurs over a large stretch of the river, posing a health risk to the people using the recreational area at' Vosloosrust, downstream from the Elsburgspruit near Kathlehong. The occurrence and large numbers of coliphage organisms occurring at certain sampling localities suggest the possible presence of the pathogenic viruses Salmonella, Pseudomonas and Candida. Effluent and seepage waters from mining areas, discharged into the Elsburgspruit were found to be low in pH and high in concentrations of certain metals such as zinc, manganese and iron. Due to the large volume of this particular effluent, the effects thereof on the water quality and fauna of the streams are felt over a distance of more than seven kilometres. As a result, the recovery of the stream from pollution is severely retarded. A number of species of the numerically dominant aquatic and semi-aquatic macrophytes which occurred within the flood-plain of the Elsburgspruit, were found to be able to absorb and to accumulate substantial concentrations of the various heavy metals, directly from the water, or from adjacent moist soils. It was also found that the Spanish reed, Arundo donax, which covers a large area of the wetland region of the Elsburgspruit in its lower section, absorbed and accumulated substantial quantities of the different heavy metals from the water of the stream. A comparison was made of the extent to which metals are deposited into the sediment under both acidic and alkaline conditions...
486

Fotoeletrooxidação na degradação de nonilfenol etoxilado em águas residuárias

Silva, Salatiel Wohlmuth da January 2013 (has links)
Os poluentes orgânicos emergentes (POE) são compostos químicos presentes numa variedade de produtos comerciais como medicamentos, produtos de higiene, agrotóxicos, surfactantes, dentre outros, podendo ser encontrados em matrizes ambientais e biológicas. Esses poluentes não são usualmente monitorados ou ainda não possuem legislação regulatória correspondente, mas apresentam risco à saúde humana e ao meio ambiente. Dentre esses POE, podemos destacar o nonilfenol etoxilado, um surfactante não-iônico utilizado no desengraxe alcalino da indústria de galvanoplastia. Esse surfactante possui uma recalcitrância e toxidade que aumenta com a diminuição do número de grupos etoxilados, processo que ocorre quando ele é biodegradado. Alguns dos produtos da biodegradação são o nonilfenol com 4, 3, 2 ou 1 grau de etoxilação e nonilfenol, este considerado disruptor endócrino imitando o hormônio natural 17β-estradiol. Tratamentos convencionais de efluentes e água não são eficientes para degradação completa desses compostos. O emprego de processos mais eficientes, como processos oxidativos e oxidativos avançados tais como a Eletrólise (E), Fotólise direta (F), Fotocatálise heterogênea (FH) e a fotoeletrooxidação (FEO), tecnologias limpas que utilizam o elétron e o fóton como reagentes, têm sido proposto como opção para a degradação desses compostos, evitando assim a contaminação dos recursos hídricos. Este trabalho foi realizado com uma solução baseada na composição de um efluente industrial contendo nonilfenol etoxilado com 4 graus de etoxilação. Os ensaios de FEO foram realizados em triplicata, variando-se a densidade de corrente, potência de lâmpada e o tempo de tratamento. Além disso, foram realizados, para efeito de comparação e elucidação de mecanismos, ensaios de eletrólise, fotólise direta e fotocatálise heterogêna. As amostras coletadas antes e após os processos oxidativos foram caracterizadas por diferentes métodos analíticos e por toxicidade. Verificou-se que no tempo de tratamento de 240 minutos as diferentes configurações de FEO não foram suficientemente eficazes na degradação de todo o poluente que se encontra na solução inicial, entretanto, a configuração FEO3 não gerou metabólitos mais tóxicos, não apresentou diferença de germinação e de crescimento de raiz, não apresentando também citotoxicidade e genotoxicidade em alface e em cebola, apresentando toxicidade apenas em peixes em uma concentração de 70,71%, o que pode ser evitado com o aumentando do tempo de tratamento, à vista disso, o processo de FEO torna-se uma opção na degradação do nonilfenol etoxilado e de outros POE, evitando assim que esses atinjam os recursos hídricos. / The emerging organic pollutants (POE) are chemical compounds present in a variety of commercial products such as medicines, toiletries, pesticides, surfactants, among others, can be found in environmental and biological matrices. These pollutants are usually not monitored or have no corresponding regulatory legislation, but present risk to human health and the environment. POE Among these, we highlight the nonylphenol ethoxylate, one non-ionic surfactant used in degreasing alkaline electroplating industry. This surfactant has a recalcitrance and toxicity increases with the decrease of the number of ethoxylate groups, a process which occurs when it is biodegraded. Some of the products of biodegradation are nonylphenol with 4, 3, 2 or 1 degree of ethoxylation of nonylphenol and this considered endocrine disruptor mimicking the natural hormone 17β -estradiol. Conventional treatment of sewage and water are not efficient for complete degradation of these compounds. The use of more efficient processes, such as oxidation and advanced oxidation processes such as direct photolysis (F), Electrolysis (E), heterogeneous photocatalysis (FH) and photoelectrooxidation (FEO), clean technologies that utilize the electron and photon reagents have been proposed as an option to the degradation of such compounds, thereby avoiding the contamination of water resources. This work was carried out with a solution based on the composition of an industrial effluent containing nonylphenol ethoxylate with 4 degrees of ethoxylation. FEO assays were performed in triplicate, by varying the current density lamp power and treatment time. In addition, we performed, for comparison and elucidation of mechanisms, testing electrolysis, photolysis and photocatalysis heterogenous. The samples collected before and after the oxidative processes were characterized by different analytical methods and toxicity. It was found that treatment time of 240 minutes, the FEO different configurations were not efficient enough to degrade any pollutants that is in the initial solution, however, the configuration FEO3 not more toxic metabolites generated no significant difference in seed germination and root growth, no significant cytotoxicity and genotoxicity also in lettuce and onion, showing toxicity on fish only at a concentration of 70.71 %, which can be avoided by increasing treatment time, the sight, the process of FEO becomes an option in the degradation of nonylphenol ethoxylate and other POE, thus preventing it reaches the water.
487

Avaliação da hidrodinâmica e da poluição no Canal de Piaçaguera, no Estuário de Santos-São VIcente (SP), a partir de informações ambientais e modelagem numérica / Evaluation of hydrodynamics and pollution at Piaçaguera Channel, on the Firth of Santos - São Vicente (SP), from numerical modeling and environmental information.

Caroline Nunes Parreira 11 April 2012 (has links)
Localizados na interface entre a terra e o mar, sistemas estuarinos estão propensos a grandes influências de substâncias que são introduzidas por diversas fontes, incluindo rios, deposição atmosférica, efluentes e escoamento de água superficial. Estas áreas, em geral, possuem um forte gradiente de concentração de substâncias químicas, onde essas são transformadas, retidas ou eliminadas. O Canal de Piaçaguera está inserido no Sistema Estuarino de Santos e São Vicente (SESS), localizado na Bacia Hidrográfica da Baixada Santista, situada na região Região Metropolitana da Baixada Santista (RMBS), que compreende os municípios de Cubatão, Santos, São Vicente, Guarujá e Praia Grande. No SESS foram implantadas, na década de 50, diversas indústrias de base (siderurgia, petroquímica e de fertilizantes), que assim como o Porto de Santos, maior da América Latina, detém alto potencial poluidor, o que fez desse estuário um grande receptor de resíduos tóxicos e efluentes líquidos contaminados. A região do Canal de Piaçaguera, área considerada mais crítica em termos de poluição desse estuário, recebe efluentes de diversas indústrias e tem como outras importantes fontes poluidoras as atividades de dragagem, deposição atmosférica, águas provenientes de drenagem superficial, esgotos clandestinos e o Porto de Santos. O presente trabalho buscou ampliar o conhecimento da poluição das águas superficiais do Canal de Piaçaguera e verificar a influência da hidrodinâmica na contaminação dessa área e em outras áreas do estuário. Primeiramente foi realizada uma avaliação dos dados de qualidade das águas superficiais da Companhia Ambiental do Estado de São Paulo (Cetesb) medidos em pontos dos rios Mogi, Piaçaguera e Cubatão, os quais despejam suas águas no canal, dos anos de 2000 a 2010. Para estimar as concentrações e área atingidas foram realizadas simulações da dispersão de poluentes em pontos dentro e fora do canal, a partir da modelagem numérica acoplada, de hidrodinâmica e dispersão. O diagnóstico de qualidade da água indica comprometimento da qualidade ambiental dos corpos dágua estudados, visto que apresentam teores acentuados de poluentes diversos e de fontes difusas, destacando-se as industriais e dos terminais portuários. O rio Piaçaguera contribuiu com o maior número de poluentes e mais elevada concentração deles. A modelagem demonstrou que o Canal de Piaçaguera apresenta circulação com energia bem menor que outras áreas do estuário, sendo notório o menor espalhamento de poluentes nessa área, de modo que a baixa velocidade das correntes no Canal é associada a menor dispersão de partículas. Considerando o lançamento contínuo de poluentes e fatores agravantes como, baixa hidrodinâmica, a bioacumulação e resuspensão dos sedimentos contaminados, é evidente que essa área necessita de maior controle e rigidez na disposição dos materiais com alto potencial poluidor. / Located at the interface between land and sea, estuarine systems are prone to large influences of substances that are introduced by various sources, including rivers, atmospheric deposition, wastewater and surface water runoff. These areas generally have a strong concentration gradient of chemicals where these are transformed, retained or eliminated. The Piaçaguera\'s channel is inserted at the estuarine system of Santos and São Vicente (SESS), located in the Santos Basin, located in the metropolitan area of Santos (RMBS), which includes the cities of Cubatao, Santos, Sao Vicente, Guaruja and Praia Grande. At the SESS were implanted, in the 1950s, several basic industries (steel, petrochemicals and fertilizers), that as the Port of Santos, Latin America\'s largest, has high pollution potential as well as the Port of Santos, what made this a great receiver estuary of toxic waste and contaminated wastewater. The region Piaçagueras channel, an area considered most critical in terms of pollution of the estuary receives effluents from various industries and its other major pollution sources of dredging activities, atmospheric deposition, water from surface drainage, underground running down and the Port of Santos . This study aimed to expand knowledge of the pollution of surface waters of the Channel Piaçaguera and the influence of hydrodynamics on the contamination of the area. We first carried out an evaluation of the data quality of surface waters of the State Environmental Company of São Paulo (Cetesb) at the points measured in the river Mogi, Piaçaguera and Cubatão, which discharge their waters into the canal, of the years 2000 to 2010. To estimate the concentrations and area affected were carried out simulations of pollutant dispersion in points inside and outside the channel from the coupled numerical modeling of hydrodynamics and dispersion. The diagnosis of water quality indicates impairment of environmental quality of the water bodies studied, since they exhibit high values concentration of various pollutants and diffuse sources, especially the industrial and port terminals. The river Piaçaguera contributed the largest number of pollutants and the higher their concentration theirs. The modeling demonstrated that the Piaçagueras channel has circulation with far less energy than other areas of the estuary, being remarkable the lowest spread of pollutants in this area, so that the low kinetic energy of currents in the channel is associated with a lower dispersion of particles. Considering the continuous discharge of pollutants and aggravating factors such as low hydrodynamics, bioaccumulation and resuspension of contaminated sediments, it is clear that this area needs greater rigidity in the control and disposal of materials with high pollution potential.
488

Gerenciamento de estoques de defensivos agrícolas banidos: estudo de casos brasileiros / MANAGEMENT OF BANNED CROP PESTICIDE STOCKPILES: BRAZILIAN STUDY CASES

Renata Stringueta Nishio 15 April 2016 (has links)
Apesar de os defensivos agrícolas atualmente classificados como Poluentes Orgânicos Persistentes (POPs) terem sua produção e uso banidos na maior parte do mundo desde a década de 1980, o gerenciamento de estoques remanescentes permanece um desafio até a atualidade. Com estimativas que variam entre 500 mil (FAO, 2015) e 2 milhões de toneladas (VIJGEN et al., 2011), poucas informações sobre seu efetivo gerenciamento e destruição são encontradas nas principais bases de dados acadêmicas sobre o tema e nos documentos oficiais da Convenção de Estocolmo sobre Poluentes Orgânicos Persistentes. O Brasil integra a lista de signatários da Convenção, mas a fabricação, o armazenamento e o uso dos agrotóxicos POPs foram proibidos em 1985, por meio da Portaria do Ministério da Agricultura nº 329. Este abrupto banimento do armazenamento colocou o agricultor brasileiro imediatamente fora da lei, uma vez que não foram planejadas medidas e procedimentos legais para dar destino adequado aos produtos que ainda estivessem em estoque nas propriedades rurais. De forma independente da Convenção de Estocolmo e das ações nacionais relacionadas a este tratado, dois estados brasileiros elaboraram programas para o levantamento de estoque dos defensivos agrícolas banidos e planejamento de sua destinação. Finalizado em 2013, o Paraná incinerou cerca de 1.200 toneladas que estavam estocadas em mais de 2.000 propriedades rurais do estado. São Paulo finalizou o inventário em 2012, resultando em 420 toneladas estocadas em aproximadamente 330 propriedades rurais. O grupo de trabalho paulista planejou as etapas seguintes e em abril de 2016, o projeto se encontrava em fase de alocação de recursos para execução das fases finais de acondicionamento, transporte e destinação. A proposta deste projeto de pesquisa é apresentar como Paraná e São Paulo gerenciaram os estoques remanescentes de agrotóxicos banidos há décadas, avaliando como os grupos de trabalho foram formados, as normativas de apoio utilizadas, como foram realizadas as etapas de levantamento de inventário e de que forma foram planejadas, financiadas, comunicadas e executadas as etapas de coleta, acondicionamento, transporte e destinação. Dessa forma, busca-se contribuir para um aumento de conhecimento prático sobre o tema e para a construção de uma política pública para gerenciamento de agrotóxicos banidos em outros estados brasileiros. / Although the pesticides currently classified as Persistent Organic Pollutants (POPs) have had their production and use banned in most of the world since the 1980s, the management of remaining stocks remains a challenge to the present. With estimates ranging from 500,000 (FAO, 2015) and 2 million tons (Vijgen et al., 2011), little information about its effective management and destruction are found in major academic databases on the subject and official documents of the Stockholm Convention on Persistent Organic Pollutants. Brazil is one of the signatories but the manufacture, storage and use of pesticides POPs were banned in 1985 by the Ministry of Agriculture Decree No. 329. However, this abrupt ban put the Brazilian farmers immediately outside the law since the government did not plan measures and legal procedures to give proper destination to the products that were still in stock on farms. Independently of the Stockholm Convention and the National Plans related to this treaty, two Brazilian states have developed programs to inventory banned pesticides and plan their destination. Finished in 2013, Paraná State incinerated about 1,200 tons that had been stored in more than 2,000 rural properties. Sao Paulo finished its inventory in 2012 resulting in 420 tons stored in about 330 rural properties. The São Paulo working group has planned the next steps and, in April 2016, the project was waiting for resource in order to implement the final stages of packaging, transport and disposal. The purpose of this research is to present as Parana and Sao Paulo managed the remaining stocks of banned pesticides evaluating how the working groups were formed, the support normative used, how the inventory has been planned and carried out and how the projects have financed, communicated and executed the steps of collection, packaging, transportation and disposal. Thus, it is expected to contribute to increase the practical knowledge on the topic and to construct a public policy for pesticide management banned in other Brazilian states.
489

Development and preliminary evaluation of novel materials for selective detection of oseltamivir in waste water / Utveckling och utvärdering av nya material för selektiv detektion av oseltamivir i vatten

Wällstedt, Elin January 2019 (has links)
This project aims to investigate whether it is possible to detect consentrations down to 0,3 µg/L of oseltamirir in waste water by Quartz Crystal Microbalance. The risks linked to this contaminant could be not only environmental, scientists have found that infuence recistence can propagate due to contaminats of this kind. Cases similar to the bird- and swine-flu could occure if the drug spreads through animals and mutate.   Four systems of different character was synthesised. As a result it was found that MAA functional monomer systems probably was interfering with charges within it’s own nanowires. Reference systems could not detect 0,01 mg/mL and HEMA polymer surfaces was the only reliable system, pH of 5,1. Lowest limit of detection (LOD) was found in Molecular Imprinted Polymer nanowires (MIP Nw) at 0,01 mg/mL and could be scaled down to 0,1 mg/L with increased loop size (injection at 10x that of 0,01 mg/mL at about 500 µL and a halved flow rate.)   An alternative could be nano structuring such as ”polystyrene balls” that possibly could be able to achieve surfaces with even more binding sites needed to detect the lowest limit at 0,3 µg/L.
490

Risk assessment of human exposure to persistent organic pollutants via indoor dust in Hong Kong

Kang, Yuan 01 January 2011 (has links)
No description available.

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