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Allen, David Peter. "Photocatalytic degradation of atrazine." Thesis, University of Bath, 1995. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296324.
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Moreau-Kervévan, Carole. "Adsorption et désorption de l'atrazine, la dééthylatrazine et l'hydroxyatrazine au contact de sols, de solides d'aquifère et de constituants isolés des sols /." Orléans : Éd. BRGM, 1997. http://catalogue.bnf.fr/ark:/12148/cb37023806r.
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Jacomini, Analú Egydio. "Bioacumulação do herbicida atrazina pelas espécies de bivalves limnicos Anodontites trapesialis (Lamarck, 1819) e Corbicula fluminea (Müller, 1774)." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/59/59139/tde-15072003-104821/.
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Inúmeros pesticidas são usados na agricultura, para controle de pragas e ervas daninhas. Dentre eles destaca-se o herbicida atrazina, intensivamente utilizado nas culturas de cana-de-açúcar, milho e sorgo, que ocupam extensas áreas no estado de São Paulo. Grande parcela do herbicida, que é aplicado na agricultura, entra em contato com o solo, podendo ser lixiviado, atingindo as águas superficiais. Neste sentido, alguns animais como, por exemplo, moluscos bivalves, podem ser utilizados como monitores biológicos do ambiente aquático e auxiliar no estudo da ecotoxicologia. Considerando o risco de contaminação do ambiente aquático pela atrazina, propõe-se, no presente trabalho, desenvolver uma metodologia de análise daquele herbicida nos tecidos nas espécies de bivalves límnicos Anodontites trapesialis (LAMARCK, 1819) e Corbicula fluminea (Muller, 1789), validar esse método e, finalmente, verificar se ocorre a bioacumulação do herbicida nas partes moles dessas duas espécies. Como técnica de extração utilizou-se a extração líquido- líquido e como técnica de análise, a cromatografia líquida de alta eficiência (CLAE).Large amount of pesticides have been used for the control of agriculture pests and weeds. Particularly important among herbicides is atrazine, extensively employed in cultures of sugar cane, corn and sorghum, that occupies an extensive area in São Paulo state. Large portions of atrazine, applied in the agricultural fields, leaches from the soil to surface water systems. In this way, some organisms such as fresh- water mollusks bivalves, can be used as biological monitors of aquatic environments, contributing for ecotoxicology studies. Considering the existence of risk of contamination by atrazine of the aquatic environment, the purpose of this work was, (i) to develop a method for the analysis of atrazine in the fresh- water bivalves species Anodontites trapesialis (LAMARCK, 1819) and Corbicula fluminea (MULLER, 1789), (ii) to validate such method and, (iii) to detect if these organisms can bioaccumulate atrazine in their tissues. This method involved a simple liquid-liquid extraction procedure, followed by high- performance liquid chromatographic analysis (HPLC).
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Wakefield, Rachael Denise. "Atrazine degradation in sub-soils." Thesis, University of Aberdeen, 1992. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU053513.
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Atrazine has been one of the most successful herbicides used both in agriculture and in urban situations. Its use has now been banned in U.K. agriculture. Atrazine applied to agricultural soils has been shown to leach down the profile with residues remaining in the soil up to 9 years after initial application. Residues are frequently found in sub-soils and aquifers world wide. In this study, systems were developed that enabled sampling and incubation of intact sub-soils cores that contained a sub-soil atmosphere. The sub-soil represents the last zone of significant potential degradation of xenobiotics, such as atrazine, as leaching into deeper soils and ground waters occurs. Conditions prevailing in these soils are different in terms of soil atmosphere, structure and activities of the soil microbial community. Laboratory studies were carried out which investigated the rate of atrazine mineralisation in intact sub-soil cores. Soil cores were aerated with either laboratory air or CO2-rich air generated through soil microbial activity from within a sealed sub-soil air reservoir. Results showed that atrazine mineralisation occurred at significantly higher rates in sub-soil cores aerated with sub-soil air compared to the rates in sub-soil cores aerated with laboratory air. Studies comparing mineralisation rates in intact sub-soil cores, incubated under sub-soil air or labroatory air, and soil biometers, containing sieved, mixed sub-soil, showed that higher rates of atrazine mineralisation occurred in the biometer studies than occurred in intact sub-soil cores. Similar studies using intact top-soil cores showed higher rates of mineralisation. Investigations carried out using intact sub-soil cores amended with a range of glucose concentrations, showed that no difference occurred in glucose mineralisation rates between soil cores aerated under sub-soil air and under laboratory air.
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Simões, Marcelo Luiz. "Aplicações de técnicas espectroscópicas e polarográficas para caracterização e avaliação da reatividade do húmus com o herbicida atrazina." Universidade de São Paulo, 1999. http://www.teses.usp.br/teses/disponiveis/76/76132/tde-20052010-165701/.
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Uma alternativa para o destino dos resíduos urbanos é a reciclagem através da compostagem e vermicompostagem (produção de húmus). A falta de padrão de qualidade destes materiais tem prejudicado o desenvolvimento dessa alternativa, tendo prejuízos, produtores e consumidores. Neste trabalho procurou-se parâmetros que pudessem ser utilizados para padronização. Por Ressonância Paramagnética Eletrônica (EPR) as amostras com nível de radicais livres semiquinona de 1017 spin/g de amostra e 1018 spin/g de carbono, ou superior, indicaram melhor qualidade do produto, no que se refere ao grau de humificação. Com o objetivo de avaliar o potencial de sorção do húmus e seu possível efeito catalítico na degradação e fotodegradação do herbicida Atrazina (AT), realizou-se vários experimentos. Resultados de espectroscopia no Ultravioleta e Visível (UV-Vis) mostraram que, para pH\'s próximos do pKa da AT (1,68) o húmus possui similar efeito catalítico que ácidos húmicos e fúlvicos na degradação da AT. Em pH neutro não foi observado degradação da AT, mesmo para altas concentrações de húmus e longos períodos de interação (262 dias). A partir de dados de Polarografia de Pulso Diferencial (PPD) em conjunto com dados de UV-Vis, observou-se uma curva de sorção da AT com máximo (20%) em torno de pH 4,0, decaindo para menos de 5% de sorção para os demais pH\'s utilizados (2,0; 6,0; 7,0; 8,0 e 10,0). Dados de EPR não mostraram reações de transferência de elétrons entre a AT e o húmus. Assim, considerando a forma da curva de sorção, observada por PPD, o mecanismo de reação mais importante entre a AT e o húmus é via ligação hidrofóbica. Experimentos de fotodegradação da AT com luz UV-Vis (300-450 nm) mostraram maior eficiência no processo quando da presença do húmus. Isto ocorreu, provavelmente, devido a ação de agentes fotooxidantes da AT, formados a partir do húmus excitado pela radiação UV. Observou-se também, uma dependência com a concentração de húmus, sendo que, dentro do intervalo de 10 a 1800 mg houve maior fotodegradação da AT para valores em torno de 300 mg.L-1.One alternative to disposal of urban residues is recycling through composts and earthworm composts (humus production). The absence of a quality standard of these materials however brings limitations to commercial development with damage to producers and consumers. In this work was proposed a strategic parameter to be used as standard. From Electron Paramagnetic Resonance (EPR) analysis samples of humus with level semiquinone free radicals of 1017 spin/g of sample and 1018 spin/g of carbon, or higher, indicated good quality of product, with adequate humification degree. Also were studied mechanisms of interaction between humus and the herbicide Atrazine (AT). The proposal was evaluate potential of AT sorption by humus and possible catalytic effect in the degradation and photodegradation of this herbicide. Data from Ultraviolet and Visible Spectroscopy (UV-Vis) showed that for pH\'s close to AT pKa (1.68) the humus showed catalytic effect in degradation of AT similar as those observed in literature with purified humic and fulvic acids. However for neutra1 pH\'s AT degradation was not observed even in the presence of high humus concentrations and long periods of interaction (262 days). Using Differential Pulse Polarography (DPP), combined with data of UV-Vis Spectroscopy, an AT sorption curve on humus was obtained showing a maximum value of 20% around pH 4.0, decreasing for less than 5% of sorption for other pH\'s analyzed (2.0; 6.0; 7.0; 8.0 and 10.0). Data from EPR gave no evidence of electron transfer reaction. So from the kind of sorption curve, obtained by DPP, the major mechanism of reaction between AT and humus was suggested to be hydrophobic bonding. Experiments of AT photodegradation using UV-Vis light (300-450 nm) showed larger efficiency of the process in the presence of the humus. This occurred probably due action of photo-oxidants on AT, originated from excitation of humus by the UV radiation. It was also observed, dependence with the humus concentration, and in the range 10 to 1800 mg.L-1 there was larger photodegradation of the AT for values around 300 mg.L-1.
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Rayner, Jennifer Leigh Ball Louise M. "Atrazine and rat mammary gland development." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2006. http://dc.lib.unc.edu/u?/etd,516.
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Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2006.Title from electronic title page (viewed Oct. 10, 2007). "... in partial fulfillment for the requirements for the degree of Doctor of Philosophy in the Department of Environmental Sciences and Engineering." Discipline: Environmental Sciences and Engineering; Department/School: Public Health.
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BOUQUARD, CORINNE. "Etude de la degradation de l'atrazine par une souche de rhizobium sp. Isolee du sol : mise en evidence de la deshalogenation et caracterisation de l'atrazine hydrolase." Besançon, 1997. http://www.theses.fr/1997BESA3705.
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Leme, Paulo Cesar. "Filmes de nanopartículas de dióxido de titânio com undecatungstofosfatomanganês(melamina) e sua reatividade frente à atrazina." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/75/75131/tde-18102010-153108/.
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Neste trabalho buscou-se produzir filmes de nanopartículas de dióxido de titânio e de nanopartículas de dióxido de titânio contendo o complexo sintetizado undecatungstofosfatomanganês(melamina) suportados em cela tubular de vidro borossiliacato e testar sua reatividade como fotocatalisadores frente à atrazina. Os ensaios de fotodegradação da atrazina foram realizados através de um reator fotocatalítico tendo como fonte de irradiação ultravioleta uma lâmpada de vapor de mercúrio de alta pressão de potência de 125 W desprovida do bulbo externo. A degradação da atrazina ocorrida nos experimentos de fotocatálise heterogênea foram acompanhados através da técnica de Espectroscopia de Absorção na Região do Ultravioleta e Visível (UV-vis) e para as amostras inicíais e finais de cada ensaio foram realizadas medidas de teor de Carbono Orgânico Total (TOC). Assim, foi possível estimar a porcentagem de degradação parcial e de mineralização da atrazina. As porcentagens de degradação obtidas para soluções contendo concentração inicial de 10 ppm de atrazina foram: no caso de filmes de nanopartículas de dióxido de titânio, obteve-se porcentagem de degradação parcial da atrazina de 42,2% a partir da análise de UV-vis e 21,8% de mineralização através da análise de TOC. Para o mesmo sistema após 72 horas, as porcentagens de degradação parcial chegaram a 71,5% a partir da análise de UV-vis e 55,5% de mineralização pela análise de TOC. Para o filme de nanopartículas de dióxido de titânio contendo undecatungstofosfatomanganês(melamina) através da técnica de UV-vis obteve-se uma degradação parcial da atrazina de 44,7% ao final de 12 horas e através da análise de TOC obteve-se 22,4% de mineralização.In this work, films of titanium oxide nanoparticles and of titanium oxide nanoparticles containing the complex undecatungstophosphatemanganese(melamine) immobilized in a borosilicate glass cylindrical cell were prepared and their reactivity as photocatalyst for atrazine were tested. The photodegradation essays of atrazine were made in a phocatalytic reactor where the ultraviolet irradiation source was one mercury vapor lamp of 125 W without the external bulb. The atrazine degradation in heterogeneous photocatalysis experiments were checked by Ultraviolet and visible spectroscopy (UV-vis) and for first and last samples for each essay were made analysis of Total Organic Carbon (TOC). So, it was possible to estimate the percentage of the partial degradation and mineralization of atrazine. The partial degradation percentages obtained for solutions with initial concentration of 10 ppm of atrazine were: In the case for films of titanium oxide nanoparticles, the partial degradation percentage for atrazine was 42,2% in UV-vis analysis and 21,8% of mineralization obtained by TOC analysis. For the same system after 72 hours, the partial degradation percentages were 71,5% in UV-vis analysis and 55,5% of mineralization obtained by TOC analysis. For the film with titanium oxide nanoparticles containing the complex undecatungstophosphatemanganese(melamine), after 12 hours, the partial degradation of atrazine was 44,7% in UV-vis analysis and 22,4% of mineralization obtained by TOC analysis.
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Pearson, Robert. "In situ remediation of atrazine contaminated groundwater." Thesis, Cranfield University, 2006. http://dspace.lib.cranfield.ac.uk/handle/1826/1430.
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The natural attenuation of groundwater pesticides by biological degradation, is widely accepted to occur at concentrations > 1 mg 1-1. However from observations of groundwater monitoring data it can be indicated that the occurrence of pesticides in groundwater is primarily at trace μg 1-1 concentrations, with 45 % of UK groundwater samples that failed the EC Drinking Water Directives PV of 0.1 μg 1-1 between 1995 – 2000, accounting for an average concentration of 64 μg 1-1. However, there are limited directed studies of in situ biological degradation of pesticides at μg concentrations. Therefore, this work was designed provided an insight as to whether any prevalent microbial adaptation can occur to degrade atrazine at μg 1-1 concentrations in groundwater. Laboratory batch studies were performed using a groundwater exposed to 0.2 μg 1-1 of the herbicide atrazine, for an excess of 10 years. Bacterial enrichment using a glucose minimal salts medium resulted in no biological degradation of atrazine, when amended at concentrations between 10 μg to 50 mg 1-1. Batch studies using the atrazine degrader Pseudomonas sp. Strain ADP as a positive control, indicated a capability to degrade atrazine within sterilised groundwater, at 50 mg 1-1 (0.92 mg 1-1 day-1) and 1 mg 1-1 (0.14 mg 1-1 day-1), but no degradation of atrazine at 100 or 10 μg 1-1. Therefore, biological degradation of trace μg 1-1 concentrations of atrazine by groundwater in situ bacteria does not readily occur. It is expected that changes in atrazine groundwater concentrations, are resulting purely from dilution, sorption or chemical degradation. Consequently, it cannot be assumed that microbial adaptation can occur to degrade atrazine at μg 1-1 concentrations in groundwaters even if in situ bioaugmentation methods are applied.
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Albuquerque, Miriam Abreu. "Degradation of atrazine in soil and subsurface." Thesis, University of Reading, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308563.
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Casillas, Ituarte Nadia Ninel. "Atrazine adsorption at the air/silica interface." The Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=osu1311957226.
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Li, Zhonghua. "Photocatalytic degradation of atrazine : a dissertation presented to the faculty of the Graduate School, Tennessee Technological University /." Click to access online version, 2007. http://proquest.umi.com/pqdweb?index=79&did=1394680461&SrchMode=1&sid=1&Fmt=6&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1255360150&clientId=28564.
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Héquet, Valérie. "Dégradations physico-chimique et photocatalytique de l'Atrazine : approche méthodologique." Aix-Marseille 1, 1996. http://www.theses.fr/1996AIX11070.
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Les voies de degradation de l'atrazine developpees lors de cette etude sont l'hydrolyse, la photolyse et la photocatalyse en presence de dioxyde de titane ainsi que de complexes metalliques (porphyrine et phtalocyanine). Le developpement d'outils experimentaux, tels que l'application de la methodologie des plans d'experiences ou une methode analytique efficace, a ete necessaire au suivi des cinetiques de degradation. La photocatalyse en presence de dioxyde de titane a montre que l'atrazine est eliminee avec un temps de demi-vie de 20 a 30 minutes sous une lampe de mercure moyenne pression et de 40 a 50 minutes sous irradiation de type solaire, pour une concentration en titane de 500 mg. 1#-#1, et de 10 mg. 1#-#1 pour l'atrazine. Les influences des facteurs tels que le ph et la matrice aqueuse ont ete evaluees. Il s'avere que la photocatalyse dans un domaine de ph neutre est preferable et que l'eau naturelle est dans ce cas un facteur peu limitant de la photodegradation. Les mecanismes de degradation en presence de dioxyde de titane sont preferentiellement la desalkylation suivie de la deshalogenation et de la desamination, l'acide cyanurique est le produit ultime de degradation. Afin de mettre en evidence la rupture du cycle triazinique, le developpement de nouveaux systemes a base de complexes metalliques (porphyrine et phtalocyanine) a ete realise. Ces systemes presentent une degradation de l'atrazine correspondant respectivement a un temps de demi-vie de 640 minutes, et de 220 minutes pour la porphyrine et la phtalocyanine etudiees sous la lampe de mercure, et un temps de demi-vie de 1070 minutes pour la porphyrine sous irradiation de type solaire. Il a ete demontre que ces catalyseurs ont, d'autre part, la faculte de rompre le cycle triazinique. Cette etude est une contribution au developpement des systemes catalytiques a base de dioxyde de titane et de complexes metalliques en application aux traitements des eaux a destination de la consommation humaine
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Evans, Wayne E. "The impact of atrazine on a chitinolytic actinomycete." Virtual Press, 1992. http://liblink.bsu.edu/uhtbin/catkey/834632.
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The impact of different atrazine concentration on a chitinolytic actinomycete and the biodegradation of atrazine by this microbe was examined.Isolates were grown in pure culture in Chitin Mineral Salts Broth with and without addition of atrazine for a two month incubation at room temperature on a rotary shaker. Visual observations, analysis by High Performance Liquid Chromatography (HPLC) and radioisotope methodology were used to determine this impact on chitinolytic activity. Analysis by HPLC and Gas Chromatography with Electron Capture Detector (GC with ECD) were used to determine the breakdown of atrazine.No atrazine derivatives were determined by HPLC and GC analysis. Only the 0.1 ppm atrazine concentration with the actinomycete culture demonstrated tolerance to the atrazine and showed chitinolytic activity in the radioactive assay and chitin derivatives by HPLC. SEM and TEM work determined that the actinomycete was actually a Streptomyces sp.Department of Biology
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Sinclair, Gail Elizabeth. "Enhanced degradation of atrazine, laboratory and field observations." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ42203.pdf.
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Steele, Kelsi Lynne. "Atrazine best management practices : impact on water quality." Thesis, Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/660.
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Zinkgraf, Matthew S. "Phytoremediation of atrazine using selected hybrid poplar genotypes /." Link to Abstract, 2004. http://epapers.uwsp.edu/abstracts/2004/Zinkgraf.pdf.
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Schaefer, Melissa Claire. "Evaluation of manufacturing processes for the production of atrazine." Thesis, Port Elizabeth Technikon, 2002. http://hdl.handle.net/10948/96.
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This report describes the results of investigations carried out with the view to find an alternative for MIBK as solvent for the production of atrazine as currently practised by Dow AgroSciences in South Africa. The main motivating factors for the said investigation was: · to increase the yield of atrazine produced, · to reduce the amount of organics, consisting essentially of reaction solvent containing dissolved product, in the aqueous process effluent, and · to improve the properties of the solid (crystalline) product to enable easier product formulation. Synthetic reactions carried out in the absence of organic solvent, i.e. in essentially a 10% NaCl solution containing a surfactant, proved rather disappointing. Low yields of atrazine were obtained together with relatively large amounts of by-products such as propazine and simazine, irrespective of the nature of the surfactant. The reason for the low yield of atrazine and high yields of by-products were established in competing substitution reactions. In these reactions, IPA was reacted with an equimolar mixture of cyanuric chloride and mono-i (first reaction intermediate) in both aqueous medium and in toluene as reaction solvent. The results of these experiments indicated that in aqueous medium IPA reacts faster with mono-i than cyanuric chloride to give propazine as by-product. In toluene, however, the preferred reaction is with cyanuric chloride to give more mono-i as product. Toluene was investigated as an alternative organic solvent to MIBK in view of its desirable properties such as low solubility in water and ease of recovery and recycling. The synthesis of atrazine was optimised in terms of addition sequence and rates of amine reagents and base (HCl acceptor), both by means of benchscale reactions and reaction calorimetry. Reaction energy profiles indicated that both the reaction of secondary amine/NaOH and primary amine/NaOH were virtually instantaneous. This implies that the reaction can be performed under feed control conditions. Of particular importance in ensuring high yields of high purity product was accurate temperature control (since both reaction steps are highly exothermic) and mixing. The latter was important in view of the rapid reaction of amine/NaOH with cyanuric chloride, as well as the possible reaction of mono-i, the first reaction intermediate, with IPA in cases of local excesses of reagent. Under optimum conditions, a yield of atrazine > 97% could be achieved where the resultant product was well within stipulated product specifications. In view of the results obtained, the following recommendations regarding the synthesis of atrazine in toluene as reaction solvent can be made: · Use a reagent addition sequence that staggers the addition of amine and NaOH in such a manner that amine is added first for a short while, followed by the simultaneous addition of amine and NaOH, and ending with NaOH. Use two reaction vessels in series, one for the IPA addition reaction and one for the MEA addition reaction. In this manner the reaction can be run on a continuous basis since no lag time between amine additions is required. Also, smaller reactors may be used whilst maintaining high production rates. Smaller reactors will improve both temperature control and mixing of reagents.
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Heydel, Laurence. "Diagnostic et maitrise des contaminations des eaux souterraines par les résidus d'atrazine." Vandoeuvre-les-Nancy, INPL, 1998. http://docnum.univ-lorraine.fr/public/INPL_T_1998_HEYDEL_L.pdf.
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Afin de préciser l'impact de l'agriculture sur la contamination des eaux souterraines et de rechercher des pratiques moins dommageables pour l'environnement et acceptables par les agriculteurs nous avons associé des approches de laboratoire et de terrain. L’évolution des teneurs en résidus d'atrazine des eaux souterraines n'a pu être corrélée avec les dates d'apport de la matière active, ni même avec la circulation de l'eau dans les bassins d'alimentation. Elle semble être le résultat de l'application continue d'atrazine depuis trente ans et des phénomènes d'immobilisation de la matière active et de ses résidus par les sols. L’immobilisation et la dégradation de l'herbicide sont très variables d'un sol à l'autre, ce qui limite les tentatives de modélisation des teneurs en résidus d'atrazine des eaux souterraines, mais permet d'identifier le sol superficiel comme étant le plus susceptible de limiter les transferts vers les nappes. Les essais réalisés à la parcelle ont montré qu'il est possible, sans pénaliser à court terme le rendement, de diminuer la concentration de la solution du sol en résidus d'atrazine, à l'aide d'un désherbage chimique limité au rang de maïs. Cette technique semble adoptable par les agriculteurs. Cependant, même en cas d'adoption massive de cette technique, nous ne pouvons pas connaitre le nombre d'années nécessaire à l'amélioration de la qualité des eaux souterraines. Des compléments d'études s'avèrent donc nécessaires pour évaluer ce temps à l'échelle du bassin d'alimentation.
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Riffi, Temsamani Khalid M. "Etude des interactions atrazine-lipides de la membrane photosynthétique." Doctoral thesis, Universite Libre de Bruxelles, 1988. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/213358.
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Lewis, Melanie L. "Characterization of a novel gram-positive atrazine-degrading bacterium." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ30806.pdf.
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Ochandio, Mario Roberto. "Spatial Analysis of Atrazine in the Elm Fork Watershed." Thesis, University of North Texas, 2000. https://digital.library.unt.edu/ark:/67531/metadc2510/.
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This study assessed the water quality of the Elm Fork Watershed with regards to the herbicide Atrazine. Atrazine is a potential environmental endocrine disruptor and carcinogen. Overall, concentrations were lower than the four-quarter drinking water average of 3 µg/Lthe Maximum Contaminant Level set by the USEPA. However, three creek stations had four-quarter average concentrations greater than 3 µg/L, and virtually all samples exceeded the 0.1 µg/L standard set in Europe [1,2]. Statistically significant differences in concentrations were detected between the 27 sampling stations and areas of high concentrations were identified. However correlations between Atrazine concentrations and land-use and precipitation were not statistically significant. Further analysis with more detailed data should be conducted before any relationships are discarded.
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Horswell, Jacqueline. "Investigation of approaches to accelerate atrazine mineralisation in soil." Thesis, University of Aberdeen, 1997. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU094707.
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Atrazine, a member of the s-triazine herbicides, appears on the EC Red List of chemicals that cause environmental concern, with residues occurring frequently in sub-soils and aquifers world-wide. Microbial metabolism is considered to be the major mechanism of complete removal of atrazine from the soil environment. Laboratory-based studies were carried out to investigate the microbial mineralisation of atrazine in soil, and to develop novel methods for potential acceleration of breakdown. In initial investigations, simple microcosm experiments were carried out to identify the importance of different fractions (water-soluble and water-insoluble) of plant residues to the dynamics, and extent of atrazine mineralisation. The amendment of soil with different plant residue fractions initially inhibited (for the water-soluble fraction) or enhanced (for the water-insoluble fraction) dynamics of atrazine mineralisation. However, by the end of the incubation, there was no overall effect on atrazine mineralisation. This suggested that increasing the soil organic matter content may render the herbicide less bioavailable to the degrader population. Investigations carried out to determine which component of the microbial biomass was more important in atrazine mineralisation showed that substantial removal of the fungal and Gram-negative bacterial population inhibited atrazine mineralisation in the soil. Experiments to selectively enrich the soil for fungal or bacterial atrazine degraders isolated a mixed bacterial culture able to accelerate atrazine mineralisation when inoculated into soil. The effect of the presence of the earthworm Lumbricus terrestris on the indigenous atrazine degrading microflora was investigated. Results indicated that atrazine mineralisation could be accelerated, but this was not primarily due to increases in microbial biomass, but possibly due to physio-chemical changes brought about by the earthworm and subsequent alterations in atrazine bioavailability.
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Yale, Rachel Louise. "The microbial basis of the accelerated degradation of atrazine." Thesis, University of York, 2015. http://etheses.whiterose.ac.uk/10436/.
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Accelerated degradation (AD) is the increased breakdown of a pesticide (or homolog) upon its repeated application and has consequences for environmental contamination and pest control. However the depth of microbial analysis into the phenomenon has been limited. Atrazine was selected as a model pesticide as its microbial degradation pathway is well characterised, enabling the microbial capacity for the degradation of atrazine to be traced. Initially a lab study showed that two applications of atrazine, at agriculturally relevant concentrations, to soils naïve to s-triazines were sufficient to induce its rapid dissipation. The emergence of AD was affiliated with the detection of the atrazine degrading genes. Six other soils with various physio-chemical properties exhibited a similar pattern of AD with average DT50 values of 28.4 days after the first application of atrazine and 1.9 days after the second. The repertoire of atrazine degrading genes varied between the soils exhibiting AD, although the gene sequences were identical. All six soils that exhibited AD contained at least one atrazine degrading gene. Upon neutralisation of a soil that did not exhibit AD, AD was restored and the atrazine degrading genes became detectable. In addition there was shown to be an effect of soil pH on the sorption of atrazine. To extend the relevance of this study beyond AD the effects of standard methodologies applied in chemical risk assessments on bacterial communities were examined and shown to reduce diversity and cause a shift in community structure. In addition the effect of rarefaction on interpreting microbial community analyses was examined. Overall the AD of atrazine was shown to be affiliated with detection of the atrazine degrading genes which may have been carried by the small portion of taxa associated with atrazine treatment. Therefore future work would focus on functional analyses to link atrazine degradation to specific taxa. In addition OECD guidelines need to consider the effects of the conditions imposed on the microbial community, while rarefaction is recommended for microbial ecology studies in line with other investigations.
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Morgan, M. K., Phillip R. Scheuerman, C. S. Bishop, and Rebecca A. Pyles. "Teratogenic Potential of Atrazine and 2,4-D Using Fetax." Digital Commons @ East Tennessee State University, 1996. https://dc.etsu.edu/etsu-works/2871.
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The teratogenic potential of commercial formulations of atrazine (40.8%) and 2,4-D was evaluated using FETAX (frog embryo teratogenic assay--Xenopus). Because these herbicides have been detected in ground and surface water, this study was designed to determine the adverse effects in buffer and natural water for both herbicides. All treatments showed a significant concentration-response effect on exposed embryos, except for the 2,4-D natural water sample. Atrazine (solubility of the commercial formula used 70 mg/L at 20 degrees C), compared to 2,4-D (solubility = 311 mg/L at pH = 1 and 25 degrees C), had a significantly greater teratogenic effect in both the buffer (atrazine EC50 = 33 mg/L, LC50 = 100 mg/L, TI = 3.03; 2,4-D EC50 = 245 mg/L, LC50 = 254 mg/L, TI = 1.04) and natural water samples (atrazine EC50 < 8 mg/L, LC50 = 126 mg/L; 2,4-D EC50 and LC50 > 270 mg/L). The 2,4-D EC50 and LC50 values for the buffer were similar at 245 mg/L and 254 mg/L. These similar values and the teratogenic index (TI) of 1.04 suggested that 2,4-D was more embryotoxic than teratogenic to frog embryos at high concentrations. Atrazine in natural water demonstrated a significantly greater EC50 (100% abnormality at 8 mg/L, the lowest test concentration) to frog embryos than the buffer experiment (EC50 = 33 mg/L). The extrapolated lowest observable adverse effect concentration (LOAEC) for the natural water experiment was 1.1 mg/L. These results suggest that atrazine toxicity is enhanced by the synergistic or additive effects of some component of the water or atrazine was already present in the sample. In contrast to atrazine, 2,4-D was less toxic in natural water than buffer. These results suggest that both atrazine and 2,4-D pose little threat, since their embryotoxicity and teratogenicity to frog embryos occur at high concentrations approaching their maximum solubility levels in water.
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Masse, Lucie. "The leaching of metolachlor, atrazine, and two atrazine metabolites in two corn fields in Quebec : a monitoring study and validation of Gleams model." Thesis, McGill University, 1990. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60455.
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A field study was undertaken during the growing seasons of 1988 and 1989 to investigate leaching characteristics of metolachlor, atrazine and two atrazine metabolites in two agricultural soils of Quebec, namely a sand and a loam field. In both years, atrazine was detected in higher levels in the groundwater of the loam field than of the sand field. Deethylatrazine was the only metabolite found in any significant quantity in soil in 1988 and in groundwater in 1989. Deisopropylatrazine was detected in groundwater at the beginning and at the end of the 1988 season and levels were similar in both fields. Metolach or was never detected in groundwater.GLEAMS predictions favourably compared to field results at the 0-20 cm depth in both years. Half-life, however, had to be reduced by half in 1989 since higher temperature had increased dissipation. GLEAMS has not predicted leaching past 20 cm in either field in 1988 and 1989. During a dry summer, such as 1988 and 1989, leaching is mostly due to macropore flow and desorption of residues, two processes which are difficult to predict with existing models.
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Monteiro, Keyle Borges e. Silva. "Remoção do herbicida atrazina por fungos de decomposição branca." Universidade Federal de Goiás, 2013. http://repositorio.bc.ufg.br/tede/handle/tede/3714.
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Given the deterioration of water resources and the growing need to meet water quality standards, alternatives to remove micropollutants from aquatic environments have become necessary. Among micropollutants, we highlight atrazine (ATZ), from the class of triazine herbicides, classified as moderately toxic to humans and highly toxic to aquatic organisms, a potent endocrine disruptor and possibly a carcinogenic. Biotechnological processes have been utilized to minimize the toxic effects of pollutants on both humans and the environment, promoting the interaction between micro-organisms and their by-products, such as enzymes. This study aimed to experimentally describe the removal of ATZ from a final concentration of 100 mg.L-1 in liquid culture medium, utilizing rot-white fungi as a future contributor in the treatment of wastewater or public water supplies. Initially assessed the tolerance of Trametes villosa, Lentinus edodes, Pycnosporus sanguineus, Pleurotus ostreatus and Pleurotus sp., in PDA (Potato Dextrose Agar) culture with nutritional variations (PDA test standard, PDA 40% and PDA 0%) in the presence of atrazine at a concentration of 100 mg. L-1 and above an application value of 500 mg.L-1. Next conducted a test 2.2-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium 0.02% (ABTS) to assess the production of ligninolytic enzymes. In these stages, the microorganisms showed both tolerance to atrazine toxicity and growth through each nutritional condition assessed, displaying decrease in growth rate at a concentration of ATZ500 mg.L-1.Morphology and mycelial growth were unsatisfactory at a low nutrient concentration (PDA 0%) when compared with PDA test standard and PDA 40%. Following a 24 hour culture period, enzymatic activity was detected through a colored halo around the microorganisms inoculant across all assessed conditions, except for Lentinus edodes and Trametes villosa, which showed activity after 96 hours, the latter only in PDA 0% culture in the presence and absence of herbicide, therefore selected for the ATZ degradation experiments in liquid culture medium. Pleurotus ostreatus and Pleurotus sp. in PDA 40% static condition yielded the highest removal concentration indexes.ATZ concentration decrease was obtained through enzymatic activity, especially that of laccase and manganese peroxidase, by means of adsorption in the biomass of the microorganisms. Atrazine concentration was determined by means of gas chromatography/high resolution mass spectrometry methods. Study results regarding Pleurotus sp., Pleurotus ostreatus and Pycnosporus sanguineus, under two distinct conditions (agitation and statics), showed their great potential in the bioremediation of aquatic environments contaminated by atrazine.
Diante da deterioração dos recursos hídricos e da crescente necessidade de atender aos padrões de qualidade da água, são necessárias alternativas para a remoção de micropoluentes de ambientes aquáticos. Dentre os micropoluentes, destaca-se a atrazina (ATZ), herbicida da classe dos triazínicos, classificado como medianamente tóxico para o ser humano e altamente tóxico para organismos aquáticos, além de ser um potente disruptor endócrino e possível agente carcinogênico. Processos biotecnológicos têm sido utilizados para minimizar os efeitos tóxicos dos poluentes para o ser humano e meio ambiente, cuja finalidade é interação entre os micro-organismos e os produtos produzidos por eles, como enzimas. O presente estudo descreve de forma experimental, a remoção da ATZ na concentração de 100 mg.L-1 em meio líquido, utilizando fungos de decomposição branca, com vistas a futuras aplicações em tratamento de águas residuárias ou de abastecimento. Inicialmente, foi testada a tolerância das espécies Trametes villosa, Lentinus edodes, Pycnosporus sanguineus, Pleurotus ostreatus e Pleurotus sp., em meio de cultura sólido contendo Batata, Dextrose e Agar (BDA) com variações nutricionais (BDA padrão, BDA 40% e BDA 0%) e atrazina nas concentrações de 100 mg.L-1 e 500 mg.L-1. Posteriormente, foi realizado ensaio com 2,2 –Azino-bis (3- etilbenzotiazolina-6 – ácido sulfônico) diamônia 0,02% (ABTS), para avaliação da produção de enzimas ligninolíticas. Nessas etapas, os micro-organismos apresentaram tolerância à toxicidade da atrazina, cresceram em cada condição nutricional avaliada com redução na velocidade de crescimento na concentração ATZ 500 mg.L-1. A morfologia e o desenvolvimento micelial não foram satisfatórios na baixa concentração de nutrientes (BDA 0%) quando comparados com os meios BDA padrão e BDA 40%. Após o período de 24 horas de cultivo, foi observada atividade enzimática com aparecimento do halo de coloração em torno do inóculo dos micro-organismos em todas as condições avaliadas, exceto as espécies Lentinus edodes e Trametes villosa que apresentaram atividade após 96 horas, e este último somente em meio de cultivo BDA 0%, na ausência e presença do herbicida, por isso não foram selecionados para os experimentos da degradação da ATZ em meios de cultura líquido. Os maiores índices de remoção foram obtidos com as espécies Pleurotus ostreatus e Pleurotus sp., no meio BD 40% em condição estática (87,5% e 87,3%), respectivamente. Os menores valores de remoção foram de 47,2% pela espécie Pycnosporus sanguineus e 53,8% pelo fungo Pleurotus sp. em BD 0%, também na condição estática. A redução da concentração da atrazina foi obtida pela atividade enzimática, com destaque para a lacase e manganês peroxidase, e pelo mecanismo de adsorção na biomassa dos micro-organimos. A concentração da atrazina foi determinada por meio do cromatógrafo gasoso com detector de massa. Os resultados dos estudos com as espécies Pleurotus sp., Pleurotus ostreatus e Pycnosporus sanguineus, sob duas condições (agitação e estática), apresentaram grande potencial para serem utilizados na biorremediação de meios líquidos contaminados com atrazina.
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Vieira, Delia do Carmo. "Fabricação de elementos vítreos porosos para o depósito de biopolímeros visando a obtenção de membranas com superfícies ativas." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/88/88131/tde-18062002-142324/.
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Este trabalho tem como foco dois aspectos principais: i) O processamento e caracterização de elementos porosos vítreos, a partir de vidro reciclado e ii) A deposição de filmes de quitosana (CHI) e carboximetilcelulose (CMC). O objetivo é a avaliação da interação superficial desses filmes com o herbicida atrazina (ATZ) em meio aquoso. O processamento seguiu o princípio do preenchimento (filler principle), fazendo uso dos sais NaCl e o MgCO3 como fases formadoras de poros. A caracterização mostra que o NaCl, age como um elemento solúvel, inerte, exceto na interface NaCl-matriz vítrea, cuja estrutura cristalina final é a cristobalita. Contrariamente, o MgCO3 reage com a matriz introduzindo novas fases como o CaMg(SiO3)2. A estrutura final, de poros e da matriz, é distinta para cada um dos sais utilizados, principalmente quanto ao aspecto morfológico dos poros e as análises semiquantitativas mostraram que o cátion Na+ na interface vidro-NaCl e o íon Mg++ atuam como modificadores de cadeia. Medidas de porosimetria indicam que nos materiais processados com NaCl apresentam estruturas dos poros abertos com uniformidade na distribuição dos tamanhos e com certa regularidade de formatos quando comparados com os materiais processados com MgCO3. Com respeito à interação herbicida - materiais vítreos, esta foi avaliada por técnicas espectroscópicas, podendo-se inferir que há interação entre as superfícies ativadas quimicamente e a ATZ. A remoção do herbicida por filtragem simples através dos filmes de CHI e filmes de CHI+CMC depositados sobre as membranas foram inferiores numericamente aos valores obtidos pela ação da superfície vítrea ausente de filmes. Entretanto, os resultados indicam que ocorre uma melhor interação entre a CHI e o ATZ, quando ambos estão em solução a pH = 3,0. Por espectroscopia de fotoelétrons excitada por raios-X (XPS) houve o aumento das espécies O (1s), C (1s), N (1s) e Cl (2s) confirmando as interações com o herbicida, porém não sendo possível inferir se esta se dá por algum grupo proveniente da CHI ou por sítios livres disponíveis na superfície vítrea. Análises numéricas indicam remoções de ATZ na ordem de 10-12% com respeito às medidas realizadas em sistemas contendo uma única membrana. Avaliação complementar da remoção do metal (Cd) confirmam a vantagem das superfícies depositadas com CHI, para este tipo de interação, indicando que sistemas compostos podem ser vantajosos na remoção de diversos contaminantes.This work is focused in two main aspects: i) The processing and characterization of porous vitreous pieces, produced from waste glass and ii) The deposition of chitosan (CHI) and carboximethilcelullose (CMC) on the vitreous surface. The evaluation of the active aspects aiming at interactions with the herbicide atrazine (ATZ) was realized in aqueous medium. The processing follows the filler principle making use of NaCl and MgCO3 as porous phases formation. Characterization showed that NaCl acts as a soluble, inert phase, with interaction over NaCl-Matrix interface, resulting in cristobalite phase as final structure. Conversely, the MgCO3 reacts along the matrix generating new phases such as CaMg(SiO3)2. The final porous and matrix structure also differs to each used salt, mainly concerning morphological aspects of the porous where semiquantitive analysis point to the Na+ in glass-NaCl interface and to Mg++ as the main chain modifiers. Measurements by porosimetry has showed that in the materials processed with NaCl the porous structure are typically open with uniform size distribution and present a certain regularity of forms when compared with the membranes processed with MgCO3. Concerning an herbicide interaction, which was evaluated by spectroscopic techniques inferring interaction between chemically active surfaces and ATZ. The herbicide removal through CHI and CHI+CMC deposited films resulted numerically lower than those values attained to glass surface absent of films. Nevertheless, the results point that to a better interaction between CHI and ATZ when both are dissolved at pH 3,0. By XPS scanning it was possible to follow the variation of the surface concentration with increasing of the elements O (1s), C (1s), N (1s) e Cl (2s) confirming surface interaction, despite not being feasible to define what functional groups take place in the interaction. Numerical analysis presents herbicide removal in the order of 10-12% concerning measure performed over a single membrane. Complementary tests of metal removal (Cd) confirmed the advantage of CHI surface in this type of interaction, making evident that composed filtration system could be ideal in the removal of distinct contaminants.
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Roux, Vincent. "Toxicite de l'aminotriazole et de l'atrazine : a propos d'une observation." Lille 2, 1990. http://www.theses.fr/1990LIL2M043.
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Wacksman, MItch. "Impact of atrazine on chlorpyrifos toxicity to four aquatic vertebrates /." Available to subscribers only, 2006. http://proquest.umi.com/pqdweb?did=1136077891&sid=35&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Rowe, Alexander M. "The effects of the herbicide atrazine on mammalian immune function." Morgantown, W. Va. : [West Virginia University Libraries], 2007. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5181.
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Thesis (Ph. D.)--West Virginia University, 2007.Title from document title page. Document formatted into pages; contains vi, 183 p. : ill. (some col.). Includes abstract. Includes bibliographical references.
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Ostrofsky, Ellen B. "Atrazine biodegradation in agricultural soils : a phenotypic and genotypic analysis /." The Ohio State University, 1998. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487953567770278.
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Morgan, M., Phillip R. Scheuerman, C. Bishop, and Rebecca A. Pyles. "The Teratogenic Potential of Atrazine and 2,4-D Using FETAX." Digital Commons @ East Tennessee State University, 1994. https://dc.etsu.edu/etsu-works/2900.
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Al, Bakri Wisam Saad Hasan. "Characterization of atrazine transport across nasal respiratory and olfactory mucosae." Thesis, University of Iowa, 2014. https://ir.uiowa.edu/etd/4559.
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The herbicide atrazine is one of the most commonly used pesticides in United States. Atrazine was banned in the European Union in 2005 because of its ubiquity in drinking water; however, in The United States more than 75 million pounds of atrazine are used annually, especially in the Midwest. Atrazine has many adverse health effects including enhancing developmental, immunologic endocrine alterations. Studies have reported that exposure to atrazine causes dopaminergic toxicity and mitochondrial dysfunction; these cellular changes have been linked to an increase in the incidence of Parkinson's disease. The objective of this study is to characterize atrazine effect on the respiratory and olfactory mucosae with specific attention to the potential for atrazine transfer to the brain via the olfactory system. Uptake of atrazine was investigated across excised nasal mucosal tissues equilibrated in Krebs's buffer (KRB) or in a co-solvent system containing propylene glycol (PG), similar to the commercial herbicide product. Active uptake pathways were probed using 2,4-dinitrophenol (2,4-DNP) as a metabolic inhibitor. Brightfield microscopy was used to assess the effects of ATZ exposure on the tissues. ATZ was found to be transported across the nasal tissues in a manner consistent with passive diffusion, and 2,4-DNP did not reduce the overall uptake of ATZ. Microscopy results showed erosion of the epithelial surface following exposure to ATZ-PG-KRB when compared to control and ATZ -KRB. These results suggest a negative effect of the ATZ co-solvent formulations on nasal tissues with the potential for increased systemic and CNS exposure.
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Fernandes, Ana Flavia Tonelli. "Caracterização fenotípica e molecular de linhagens de Pseudomonas spp. envolvidas na biodegradação da atrazina." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/60/60135/tde-09042014-104656/.
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A atrazina é um herbicida amplamente utilizado no Brasil e no mundo em diferentes culturas agrícolas, principalmente em culturas de milho, sorgo, soja e cana-de-açúcar, entretanto, pode se tornar um contaminante de águas superficiais e subterrâneas e do solo, gerando uma preocupação ambiental, pois desequilibra e interfere no ecossistema. A atrazina pode sofrer biodegradação, tornando o processo de biorremediação uma alternativa viável e ecologicamente aceitável para o tratamento de ambientes contaminados por esse herbicida. O microrganismo de referência nesse processo de biodegradação é a Pseudomonas sp. ADP que possui o plasmídio pADP-1, no qual se localizam os genes atzA, atzB, atzC, atzD, atzE e atzF, que codificam enzimas atuantes na via de degradação da atrazina. O presente estudo teve como objetivo o isolamento e a caracterização de bactérias do gênero Pseudomonas quanto à presença de genes de degradação da atrazina e quanto à capacidade de degradação desse herbicida. No presente trabalho foram isoladas 123 cepas de amostras de solo de diferentes regiões do Brasil, as quais foram caracterizadas através de provas bioquímicas e moleculares e identificadas como Pseudomonas aeruginosa (74,8%) e outras espécies (25,2%) pertencentes aos gêneros Pseudomonas, Achromobacter, Burkholderia, Cupriavidus e Rhizobium. A variabilidade genética dos isolados pertencentes ao gênero Pseudomonas foi analisada através da técnica de ERIC-PCR e demonstrou que todos os isolados apresentam alta diversidade genética (<80%). Os genes atzA, atzB, atzC, atzD, atzE e atzF foram detectados em seis isolados provenientes de amostras de solo das regiões Norte, Nordeste, Sudeste e Centro-Oeste do Brasil, sendo três deles da espécie Pseudomonas aeruginosa, um Cupriavidus pauculus, uma Burkholderia cepacea e um Rhizobium radiobacter. Apenas três isolados contendo os genes atz apresentaram plasmídios. Os isolados bacterianos que apresentaram os genes atz foram testados quanto à capacidade de crescimento utilizando a atrazina como única fonte de nitrogênio e quanto à capacidade de degradação desse herbicida. Todos os isolados testados apresentaram crescimento em meio ATZ-R, mas não foi possível observar a mineralização do herbicida, tanto em meio sólido quanto em meio líquido, todavia observou-se a degradação da atrazina por uma espécie de Pseudomonas aeruginosa (isolado P86), com redução de 44%, em meio líquido ATZ-R contendo 33 ppm de atrazina.Atrazine - the herbicide widely used in Brazil and all over the world in different agricultural crops mainly in corn, sorghum, soy, and sugar cane can contaminate the superficial and subterraneous water, and soil creating an environmental concern due to imbalance and interference caused in ecosystem. Atrazine can suffer biodegradation, which can make the bioremediation process a viable and ecologically acceptable alternative for the treatment of the environment contaminated with this herbicide. The microorganism referred on that biodegradation process is Pseudomonas sp. ADP which has pADP-1 plasmid, where are the genes atzA, atzB, atzC, atzD, atzE, and atzF that codify active enzymes on atrazine degradation way. The aim of this present study was the isolation and the characterization of Pseudomonas genus bacteria due to the presence of the atrazine degradation genes, and the capacity of degradation of this herbicide. In the present work 123 samples of soil bacteria from different Brazilian regions were isolated, and characterized by biochemical and molecular tests, and identified as Pseudomonas aeruginosa (74.8%) and other species (25.2%) of Pseudomonas, Achromobacter, Burkholderia, Cupriavidus, and Rhizobium genus. Genetic variability of the isolated of Pseudomonas genus was analyzed by the ERIC-PCR technique, and demonstrate that all the isolated ones presented high genetic diversity (<80%). atzA, atzB, atzC, atzD, atzE, and atzF genes were detected in six isolated of soil samples from North, Northeast, Southeast, and Midwest of Brazil being 3 Pseudomonas aeruginosa, 1 Cupriavidus pauculus, 1 Burkholderia cepacea, and 1 Rhizobium radiobacter. Only 3 isolated with atz genes presented plasmids. Bacterial isolates that presented atz genes were tested for growth and degradation capacity using only atrazine as nitrogen source. All tested isolates presented growth on ATZ-R, but mineralization of this herbicide in solid or liquid media was not possible to observe. However, 1 specie Pseudomonas aeruginosa (isolate P86) presented atrazine degradation (reduction of 44%) in ATZ-R liquid media with 33 ppm of atrazine.
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Nguyen, Hanh Linh. "development of novel efficient sensors for the recognitions of different water species – aluminium ions, potassium ions, atrazine and glyphosate." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLN067.
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La conception, la synthèse et l’étude des propriétés photophysiques de sondes fluorescentes d’espèces moléculaires ou de cations présente beaucoup d’intérêt dans des domaines aussi divers que l’environnement et la biologie. En particulier, les cations polluants (cations d’aluminium, cations de potassium) et les résidus de pesticides (tels que le glyphosate ou l’atrazine) qui n’étant pas dégradés par le métabolisme, ils se retrouvent dans les eaux de boissons à des concentrations délétères pour l’environnement. Les méthodes analytiques actuelles telles que la spectroscopie d'absorption atomique, la spectroscopie de masse sont coûteuses et ne peuvent être utilisées que pour les déterminations à l'intérieur. Inversement, l'utilisation de la technique de fluorescence offre des avantages distincts en termes de sensibilité, de sélectivité et de développement potentiel d'appareils portables.Dans cette thèse, des sondes fluorescentes efficaces pour la détection de l'aluminium, du potassium, du glyphosate et de l'atrazine ont été ciblées. Pour l'aluminium, une nouvelle sonde hydrosoluble (PSSA) a été synthétisée, reconnaissant les cations d'aluminium sur la base du mécanisme d'amélioration de l'émission induisant une agrégation. Avec une limite de détection de 153 nM et une bonne propriété de sélectivité, le PSSA a également été intégré avec succès dans un système PDMS / verre afin de permettre l’utilisation d’un dispositif portable pour la détection de l’aluminium.Ensuite, deux sondes synthétisées différentes de notre laboratoire (Calix-Rhod-aza et DMAP-BARB) ont été considérées dans cette thèse. Ces sondes ont été développées pour la détection de potassium et d'atrazine, respectivement. Pour les deux molécules, la photophysique et la complexation vis-à-vis d'espèces ciblées ont été étudiées, et deux configurations différentes de microfluidique capillaire en PTFE ont été réalisées pour leur détection, avec des limites de détection très satisfaisantes (qui bien conformes à la gamme des normes réglementaires).Enfin, des efforts ont été consacrés à la conception et à la synthèse de nouveaux capteurs pour le glyphosate. Quatre sondes différentes ont été conçues (GlyP-a, GlyP-b, GlyP-c, GlyP-d). GlyP-a a été faite, alors que les autres étaient à deux pas de la réalisation. En effet, ce projet est toujours en cours dans notre laboratoire, en prenant les résultats préliminaires de ce travailThe design, synthesis and photophysical studies of fluorescent sensors of neutral molecules or cations are of great interest in environment and biology. In particular, metal-based pollutants (aluminium cations, potassium cations) and pesticide residues (such as glyphosate or atrazine) which are not degraded by the metabolism can be found in drinking water at harmful concentrations to the environment. Actual analytical methods such as atomic absorption spectroscopy, mass spectroscopy are expensive and can only be used for indoor determinations. Conversely, the use of fluorescence technique offers distinct advantages in terms of sensitivity, selectivity with a potential development of portable devices.In this thesis, efficient fluorescent probes for the sensing of aluminium, potassium, glyphosate and atrazine were targeted. For aluminium, a novel water-soluble probe (PSSA) was synthesized, which recognize aluminium cations based on aggregation-induce emission enhancement mechanism. With a detection limit of 153 nM and good selectivity property, PSSA was also successfully incorporated onto a PDMS/glass system for enabling a portable device for aluminium detection.Next, two different synthesized probes from our laboratory (Calix-Rhod-aza and DMAP-BARB) were considered in this thesis. These probes were developed for potassium and atrazine sensing, respectively. For both molecules, the photophysical and complexation towards targeted species were studied, and two different PTFE capillary microfluidics set-ups were realized for their detection, with highly satisfactorily detection limits (well in accordance with the range of the regulation standards).Finally, efforts were given on the design and synthesis of new sensors for glyphosate. Four different probes were designed (GlyP-a, GlyP-b, GlyP-c, GlyP-d). GlyP-a has been made, while the others were just one step away from realization. Indeed, this project is still under progress in our laboratory, taking the preliminary results from this work
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Neitsch, Susan Lynn. "Adsorption and desorption of atrazine on a melamine-based soil amendment." Thesis, Texas A&M University, 2004. http://hdl.handle.net/1969.1/567.
Full textAbstract:
Adsorption kinetics and adsorption-desorption of atrazine on organoclay composites prepared with the surfactant 6-piperazin-1-yl-N,N'-bis-(1,1,3,3-tetramethyl-butyl)-(1,3,5)triazine-2,4-diamine and Houston Black clay were studied using the indirect batch equilibration procedure. The organoclay composites sorbed significantly more atrazine than the Houston Black clay. Adsorption equilibrium was reached after 72 h for the organoclay composites. Atrazine adsorption isotherms were described by linear partitioning. The Koc values ranged from 605 to 5271 L kg-1 for the organoclay composites compared to a value of 41 L kg-1 for the Houston Black clay. The organoclay composite containing 20% surfactant on a total weight basis provided the most efficient adsorption of atrazine, although organoclay composites containing much lower amounts of surfactant also adsorbed significant amounts of atrazine. An average of 11% of sorbed atrazine was released during desorption. Characterization of desorption products showed only atrazine molecules being released from the organoclay composites.
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Smith, Ward N. (Ward Nolan). "Leaching of 14C radio-labelled atrazine in long intact soil columns." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60459.
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A leaching study was undertaken with $ sp{14}$C radio-labelled atrazine in long, intact, soil columns to investigate the fate and transport of atrazine in a Quebec sandy loam soil and to test two contaminant transport models, namely PRZM and LEACHMP.Results indicated a large variation in atrazine concentration. The maximum levels in the leachate of the soil columns ranged from 0 to 11.2 $ mu$g/L. Deisopropyl-atrazine, the principal metabolite in the soil columns, was detected near the soil surface and did not leach beyond 15 cm depth. The adsorptive and desorptive capacity of atrazine in the soil columns was mainly attributed to organic matter and moisture content.
LEACHMP was found to be superior in predicting hydrologic characteristics in the soil columns as compared to PRZM which required calibration. Both models underestimated levels of atrazine near the soil surface and in the leachate (115 cm depth). The results from first and second order analysis for PRZM and LEACHMP showed considerable uncertainty in atrazine fate and transport. First and second order analyses were found to be useful tools in indicating where efforts to reduce uncertainty can best be directed.
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Somerset, Mark. "Effects of the s-triazines irgarol and atrazine on bivalve molluscs." Thesis, University of Portsmouth, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.502738.
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McMillan, Oliver. "Characteristics and mechanisms of atrazine sorption to biochar for land remediation." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/277807.
Full textAbstract:
Contaminated land is a widespread, global issue affecting millions of people. Atrazine is a commonly used herbicide which often contaminates groundwater and drinking water supplies and is associated with adverse health outcomes. Biochar is the solid product of pyrolysis and is associated with several environmental benefits. It may be an effective remediation tool when used as a soil amendment. This thesis investigates the mechanisms through which biochar can immobilise atrazine, and the implications of the mechanisms for remediating contaminated land. Nine biochar samples were obtained from the United Kingdom Biochar Research Centre , which were produced from softwood pellets (SWP), wheat straw pellets (WSP), miscanthus straw pellets (MSP), rice husk (RH) and oil seed rape (OSR) each at pyrolysis temperatures of 550°C and 700°C (excluding OSR at 700°C). The sorption mechanisms controlling atrazine sorption to these biochars were determined through various characterisation methods and batch sorption experiments. The sorption tests showed that sorption to each of the standard biochars occurs via multiple simultaneously occurring mechanisms, which are each promoted under certain conditions. Studies investigating sorption kinetics, isotherms and interactions with humic acids showed that for all biochars in this study, pore filling was a significant process through which atrazine is transported to adsorption sites, although poor intraparticle diffusion for softwood and oil seed rape biochars can prevent efficient transport. Wheat straw and rice husk biochars showed effective pore diffusion, resulting in high sorption capacities. Partitioning was associated with poor remediation outcomes and was significant to softwood biochars, although adsorption dominated overall sorption for all other biochars. pH was shown to significantly influence the occurrence of various sorption mechanisms. At low pH values, most biochars showed evidence of electrostatic repulsion between positive atrazine species and the positively charged biochar surface. At intermediate pH values, all biochars showed strong hydrogen bonding between H+ groups on the surface of the biochar and atrazine. A meta-analysis of previous relevant studies provided further evidence for hydrogen bonding of atrazine to biochar and showed that hydrophobic effects likely play little role in adsorption after accounting for the effects of surface area. Varying contributions of π-π EDA interactions, hydrogen bonding involving biochar O- groups, and interactions with ash minerals resulted in different sorption profiles for each biochar at high pH values. In order to further determine the mechanisms controlling sorption at high pH, surface compositions of SWP550, RH700 and OSR550 biochars were modified using hydrofluoric acid. Modification with hydrofluoric acid successfully removed the ash contents of rice husk and oil seed rape biochars and reduced atrazine removal at high pH values. This suggested that the ash fraction increases atrazine removal at high pH through complexation or catalytic hydrolysis. The roles of the various mechanisms are related to remediation outcomes in a novel manner allowing for the improved design of biochar for environmental remediation.
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Munjanja, Basil Kudakwashe. "Comparison of pesticide deposition sampling methods for spray drift of atrazine." Diss., University of Pretoria, 2019. http://hdl.handle.net/2263/77862.
Full textAbstract:
Off-target deposition is a potential route of pesticide entry into the environment. To
determine off-target deposition of pesticides, various deposition samplers are used. A study
was carried out to compare a number of deposition samplers (chromatography paper, glass
microscope slides, glass petri dishes, polyacrylic rods) used in spray drift determination of
atrazine (and terbuthylazine when present in the formulation). The first sampling campaign
was conducted to compare three horizontally oriented deposition samplers (glass microscope
slides, chromatography paper, and glass petri dishes) and two vertically oriented deposition
samplers. The second sampling campaign consisted of horizontal and vertical
chromatography paper only, as this sampler provided the best results in the first sampling
campaign. In each of the spraying events of atrazine three sampling lines were used. In the
first application, the sampling distances were 0, 10, 25, 50, 100, 200, and 400 m. In the
second application, the sampling distances were 0, 10, 30, 50, and 100 m. In addition,
corresponding upwind control deposition samplers were also included in each pesticide
sampling campaign. Analysis of pesticide deposition samples for both sampling campaigns
was done by GC-MSD. The limit of detection (LOD) for atrazine was 0.006 μg.ml-1 (1st
sampling campaign) and 0.01 μg.ml-1 (2nd sampling campaign), and 0.02 μg.ml-1, for
terbuthylazine (2nd sampling campaign) respectively. Excellent recoveries of >70% were
obtained by sonication extraction of chromatography paper, glass petri dishes, glass
microscope slides, and polyacrylic rods. The precision in terms of %RSD was less than 20%.
In the first sampling campaign, the chromatography paper was the best deposition sampler,
and atrazine levels deposited on the samplers were up to 0.012 μg.cm-2. In the second
sampling campaign, both atrazine and terbuthylazine were detected, and deposition levels
were up to 11 μg.cm-2, and 12 μg.cm-2 respectively. Comparison of field deposition data and
AgDISP modelled data showed that the model under-predicted the amount of atrazine in the first sampling campaign. In the second sampling campaign, the model under-predicted only at
0 m, but as the distance increased, there was agreement between the AgDISP and the field
deposition results. Thus, the findings of this study make it apparent that field deposition
studies are still important to arrive at buffer distances that accurately reflect environmental
concentrations of off-target deposition during pesticide application. For the first time, this
project has shown the comparison of various samplers with different materials of construction
in the off-target deposition of a pesticide active ingredient (atrazine), under local South
African conditions.Dissertation (MSc)--University of Pretoria, 2019.
Chemistry
MSc
Unrestricted
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Nguyen, Vu, Thi Thuy Trang Nguyen, Thi My Chi Vo, and ThanhSon Dao. "Single and binary effects of atrazine, copper and chromium on duckweed." Technische Universität Dresden, 2019. https://tud.qucosa.de/id/qucosa%3A70809.
Full textAbstract:
Recently, the agricultural, industrial and mining activities have led to increase in contaminant emission. Trace metals or herbicides are among the pollutants to be concerned in the world. In this study we evaluated the effects of the herbicide atrazine (at the concentrations of 5, 50 and500 µg L-1) and its combination with copper (Cu, 50 µg L-1) and chromium (Cr, 50 µg L-1) on duckweed over the period of 10 days in the laboratory conditions. We found that 50 and 500 µg atrazine L-1 severely impacted on the growth or even caused the death of the plants, whereas there was no statistically significant difference in the duckweed growth rate between the 5 µg atrazine L-1 exposure and control. In the combined treatments (50 µg atrazine L-1 with Cu; with Cr or with both Cu and Cr), the plant growth rate of atrazine with either Cu or Cr was strongly reduced. However, the mixture of atrazine with Cu and Cr did not significantly decrease the development and growth rate of duckweed. Besides, atrazine and investigated heavy metals resulted in turning whiteof duckweek leaves that evidence ofthe chlorophyll degradation. Our results showed the negative influences of the herbicide atrazine and metals on development and morphology of duckweed.Gần đây, những hoạt động nông nghiệp, công nghiệp và khai khoáng đã và đang dẫn đến sự gia tăng phát thải các chất gây ô nhiễm. Kim loại nặng hoặc thuốc diệt cỏ là những chất gây ô nhiễm đang được quan tâm trên thế giới. Trong nghiên cứu này, chúng tôi đánh giá ảnh hưởng của thuốc diệt cỏ atrazine (nồng độ 5, 50 và 500 µg/L) và sự kết hợp của chất này với đồng (Cu, 50 µg/L) và crom (Cr, 50 µg/L) lên bèo tấm trong thời gian 10 ngày trongđiều kiện phòng thí nghiệm. Chúng tôi nhận thấy atrazine tại nồng độ 50 và 500 µg/L đã gây nên những ảnh hưởng nghiêm trọng lên sự phát triển hay thậm chí làm cho bèo tấm bị chết, trong khi đó, không ghi nhận được bất kì sự khác biệt có ý nghĩa thống kê về tốc độ tăng trưởng của bèo tấm giữa lô thí nghiệm phơi nhiễm 5 µg atrazine / L và lô đối chứng. Trong những lô phơi nhiễm kết hợp (50 µg atrazine / L với Cu, với Cr hoặc với đồng thời Cu và Cr), tốc độ tăng trưởng của bèo tấm khi phơi nhiễm với atrazine và Cu hoặc Cr bị giảm mạnh, tuy nhiên, việc phơi nhiễm đồng thời atrazine với Cu và Cr đã không làm giảm đáng kể sự phát triển và tốc độ tăng trưởng của bèo tấm. Bên cạnh đó, atrazine và kim loại nặng đã làm cho màu của lá bèo tấm chuyển sang màu trắng, điều này chứng tỏ có sự suy giảm chlorophyll. Kết quả nghiên cứu này đã cho thấy những ảnh hưởng tiêu cựccủa thuốc diệt cỏ atrazine và kim loại lên sự phát triển và hình thái của bèo tấm.
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Malotaux, Christophe. "Les Triazines-atrazine entre autres, présences dans l'environnement et dans l'eau." Paris 5, 1992. http://www.theses.fr/1992PA05P242.
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Lakshminarayan, Sooraj T. K. "Distribution and determinants of Atrazine exposure among Central Ohio farm families." The Ohio State University, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=osu1407234952.
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Godfrey, Jake A. "Impact of an atrazine-based herbicide on an agrobiont wolf spider." Miami University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=miami1505300839212697.
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Pagan, Steven Schulte Mitchell Darin. "Atrazine transport through a glacial till aquifer in north-central Missouri." Diss., Columbia, Mo. : University of Missouri--Columbia, 2009. http://hdl.handle.net/10355/6578.
Full textAbstract:
The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on November 20, 2009). Thesis advisor: Dr. Mitchell Schulte. Includes bibliographical references.
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Anselmo, Fábio. "Estudo experimental dos efeitos da exposição repetida ao herbicida atrazina sobre a atividade neurocomportamental, biomarcadores do estresse oxidativo e sistema dopaminérgico." Botucatu, 2020. http://hdl.handle.net/11449/192190.
Full textAbstract:
Orientador: Antonio Francisco GodinhoResumo: O herbicida atrazina (ATR) é um praguicida usado intensivamente na agricultura, que persiste no meio ambiente e causa toxicidade em espécies não-alvo, inclusive seres humanos. Considerando o potencial da ATR para produzir efeitos no sistema nervoso central (SNC) e a falta de informações na literatura corrente sobre esse tipo de toxicidade, o objetivo deste projeto de pesquisa foi avaliar os efeitos da exposição subcrônica ao herbicida ATR sobre parâmetros neurocomportamentais específicos e estabelecer sua correlação com o estresse oxidativo (EO) em tecido cerebral de ratos e com o sistema dopaminérgico em regiões específicas do cérebro, nominalmente córtex pré-frontal (CPF), hipocampo (HIP) e corpo estriado. Ratos Wistar machos receberam solução salina (0,3 ml; controle - Ct), atrazina (ATR; 100 mg/kg), atrazina mais vitamin E (ATR; 100 mg/Kg + VE; 200 mg/kg), apenas vitamina E (VE; 200 mg/kg), atrazina mais levodopa (ATR; 100 mg/Kg + LEV; 20 mg/kg) e apenas levodopa (LEV; 20 mg/kg), por gavage, durante 28 dias. O comportamento foi avaliado utilizando arena de campo aberto (ACA), labirinto em cruz elevado (LCE) e hole-board (HB). O teste de estresse oxidativo no tecido cerebral avaliou os níveis de malondialdeído (MDA), capacidade antioxidante hidrofílica (CAH) e atividade das enzimas superóxido dismutase (SOD) e catalase (CAT). A dopamina (DA) foi quantificada por HPLC, em áreas cerebrais específicas (CPF, HIP e estriado). Exposição à ATR provocou ansiedade, diminuiu a coord... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Atrazine (ATR) herbicide is a pesticide used intensively in agriculture that persists in environment and causes toxicity on non-target species, include humans. Considering the potential of ATR to produce effects on the central nervous system (CNS) and the lack of information in the current literature about this type of toxicity, the aim of this research project was to evaluate the effects of subchronic exposure to ATR herbicide on specific neurobehavioral parameters and to establish its correlation with oxidative stress (OE) in rat brain tissue and with the dopaminergic system in specific brain regions, nominally prefrontal cortex (PFC), hippocampus (HIP) and striatum. Male Wistar rats received saline (0.3 ml; control - Ct), atrazine (ATR; 100 mg/kg), atrazine plus vitamin E (ATR; 100 mg/Kg + VE; 200 mg/kg) only vitamin E (VE; 200 mg/kg), atrazine plus levodopa (ATR; 100 mg/Kg + LEV; 20 mg/kg) and only levodopa (LEV; 20 mg/kg), via gavage, during 28 days. Behavior was assessed using open field arena (OF), elevated plus-maze (EPM) and hole-board (HB) apparatus. Oxidative stress assay in brain tissue evaluated malondialdehyde (MDA) levels, hydrophilic antioxidant capacity (HAC), and superoxide dismutase (SOD) and catalase (CAT) enzymes activity. Dopamine (DA) was quantified using HPLC, in specific brain areas (PFC, HIP and striatum). ATR exposure caused anxiety-like behavior, decreased motor coordination and did not alter the locomotor activity of the animals. ATR did not chang... (Complete abstract click electronic access below)
Doutor
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Hayar, Salem. "Influence d'un inoculum fongique, d'amendements organiques et minéraux sur la dégradation de l'atrazine : cas d'un sol présentant une microflore autochtone adaptée ou une faillibilité microbienne." Université Joseph Fourier (Grenoble), 1999. http://www.theses.fr/1999GRE18007.
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Schenck, Brown Julie Eileen. "Atrazine Contamination and Suspended Sediment Transport within Logsdon River, Mammoth Cave, Kentucky." TopSCHOLAR®, 2008. http://digitalcommons.wku.edu/theses/38.
Full textAbstract:
Understanding the potential for karst aquifer contamination by sediment-sorbed pesticides is important for cave conservation efforts in agricultural landscapes. Flow rate, water quality parameters and suspended sediment concentrations were measured in Logsdon River, a ~10km karst conduit within the Turnhole Spring Groundwater Basin of Mammoth Cave National Park to determine characteristics of storm-period transport of sediment-sorbed atrazine through a conduit-flow karst aquifer.
Analysis of two independent precipitation events occurring in the Spring of 2008 from May 2-4 and May 27-29 demonstrated the rapid response of the Logsdon River to precipitation events with detections of atrazine increasing during the initial turbidity peak and decline in spC, indicating that the atrazine arrives with the initial flush of surface waters that enters the conduit. Distinct peaks of atrazine did not coincide with fine grained (silt and clay-sized) sediment peaks and concentrations of atrazine remained elevated on the falling limb of the hydrograph as turbidity declined. In addition, no systematic relation between filtered and unfiltered samples was evident. There was also exceedingly weak correlation between the concentration of atrazine and suspended sediment, suggesting that if atrazine is sorbed to fine sediment particles this sorption involves only the fractions finer than 0.22 μm.
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Sharp, Scotty. "Assessment of Atrazine in a Rural Water Source: Rough River Lake, Kentucky." TopSCHOLAR®, 2006. http://digitalcommons.wku.edu/theses/264.
Full textAbstract:
Atrazine [2-chloro- 4-(ethylamino)-6-(isopropylamino)-l,3,5-triazine], a widely used herbicide in US corn production, impacts quality of drinking water for many rural water supply systems. Four systems at Rough River Lake, Kentucky, have had high levels of atrazine in raw water and in some cases finished water that have exceeded the legal limit of 3 parts per billion (ppb). The Rough River Lake watershed is 1,700-km2, much of which is located in limestone karst. A hypothesis was developed stating that there would be higher concentrations of atrazine in the northeast section of the Rough River Watershed, located in Hardin County, due to the no-till corn production of the area and karst features. Surface and subsurface samples were collected from eighteen locations (including all major tributaries) within the study area. Sampling began during the Spring of 2005 growing season on a fourteen-day cycle and a twenty-eight day cycle during the fall and winter months. Atrazine concentrations rose at nearly all sites within weeks of the spring application in May, and then began to decrease by late July. Five locations had over 3 ppb for at least two sampling rounds. Two sites exceeded 10 ppb. Global Polynomial Interpolation Analysis was used as both a data exploration tool and a way to demonstrate a definite spatial and temporal pattern to atrazine within the study area. It was also concluded, the reservoir with its larger volume and lower water velocity plays a significant affect on a longer residence time of atrazine, while the tributaries showed lower concentrations of atrazine most likely due to higher velocity and smaller volume of water.