Pollution of water by herbicides and heavy metals has caused world wide concern because of the adverse effects of these pollutants on the environment, humans and wildlife. This has resulted in tighter legislation being imposed on the levels of these pollutants in drinking water. For example, the European Union (EU) has set the legislation in the drinking water Directive Admissible Concentration for a single herbicide to a maximum of 0.1 ppb. Despite the tight environmental pollution controls, isolated cases of pollutants exceeding their limits are still encountered. This would suggest that research towards the efficient and effective removal of these pollutants will be an on-going process. In this study, sorption of copper and some selected herbicides e.g. atrazine, benazolin and 2,4-dichlorophenoxyacetic acid (2,4-D) was undertaken on a conventional activated carbon and its modified series. A low level detection method was developed using High Performance Liquid Chromatography (HPLC) and this system was used to quantify the sorption capacity of the herbicides. In order to understand the sorption mechanism of the targeted pollutants, physical and chemical characterisation of the adsorbents was undertaken using a variety of techniques. These include, Scanning Electron Microscopy (SEM), X-ray Photoelectron Spectroscopy (XPS), Fourier Transform Infrared (FT-IR) method, pore size distribution and surface area measurements, elemental analysis, sodium capacity determination, zeta potential and pH titration. The sorption data were presented and analysed by conventional adsorption isotherms. Sorption of the herbicides was favoured on carbon samples with least oxygen content while the uptake of copper was strongest in oxidised carbons. Kinetic experimental data were analysed by a pseudo second order model and the Boyd kinetic model. Molecular structural configurations and the physico-chemical properties of the adsorbent played a crucial role in the sorption behaviour of the herbicides.

Pesticides are an important component of New Zealand’s primary production sectors. Infestation of pests and diseases can affect crop yield, crop value and damage the country’s export reputation, resulting in economic losses. Repeat applications of pesticides, however, can result in contamination of land and water. Therefore, it is important to understand the fate of pesticides in the environment. Factors which can affect pesticide persistence include soil properties (pH, SOM, CEC), leaching and run-off, volatilisation and co-contamination with heavy metals. Many soils in New Zealand contain high levels of copper from historical applications of copper-based pesticides. Co-contamination of soils may lead to the persistence of some synthetic organic pesticides. An investigation was undertaken to determine the effects of co-contamination with copper on the biodegradation of atrazine and indoxacarb in a New Zealand soil. A Templeton sandy loam soil was spiked with CuSO₄ to achieve concentrations of 0, 100, 250, 500 and 1000 mg kg⁻¹ Cu. The spiked soils were field aged for six months prior to pesticide spiking with either atrazine or indoxacarb. The aged Cu-spiked soils were spiked with either atrazine or indoxacarb at a rate of 2 mg kg⁻¹. A glasshouse study was conducted to determine if copper inhibited the degradation of the pesticides. The pesticide-spiked soils were sampled at the time of spiking (t₀), at the estimated half-lives (t₁) and at twice the estimated half-lives (t₂) of the individual pesticides. The estimated half-lives were based on literature values. The bioavailability and subsequent adverse effects of copper on the soil microbial community was investigated. Total and bioavailable copper concentrations, phosphatase and urease enzyme activities, microbial biomass, and pesticide residue concentrations were all measured in the experimental soil. Methods were developed for the extraction of atrazine, atrazine metabolite and indoxacarb residues from the experimental soil. Total copper concentrations extracted ranged from 4–1060 mg kg⁻¹ in the experimental soils and were consistent throughout the pesticide degradation studies. The bioavailability of copper was a maximum of 2% of the total copper concentration. Bioavailable copper concentrations were positively correlated to total copper (p<0.01). Soil biological properties were investigated to determine the effects of copper on the soil microbial community. Phosphatase and urease enzyme activities, as well as microbial biomass concentrations, were negatively correlated with total copper (p<0.05). Total copper was a better indicator of effects on microorganisms than bioavailable copper. The soil biological properties began showing adverse effects above a total copper concentration of 100 mg kg⁻¹. This concentration also corresponds to New Zealand’s copper limit in biosolids, which is protective of human, plant and microorganism health. Phosphate buffer extraction methods were developed for the analysis of atrazine and indoxacarb residues in the experimental soil by HPLC-UV. Elevated copper concentrations did not inhibit the degradation of atrazine or indoxacarb in the experimental soil. The half-lives of both atrazine (≤19.4 d) and indoxacarb (≤18.8 d) were lower in the spiked experimental soils than the means reported in previous New Zealand and international studies, but were within the reported ranges. This study provided the first data on the fate of indoxacarb in New Zealand. Hydroxyatrazine was the only metabolite detected in the atrazine-spiked experimental soils. Significant differences between the control (Cu-1) and copper levels above 100 mg kg⁻¹ were observed for hydroxyatrazine at t₂. Significant negative correlations were observed between hydroxyatrazine and the microbiomass at t₁ and phosphatase activity at t₂ (p<0.05). These significant relationships suggest that elevated copper concentrations may alter the degradation of this metabolite in the experimental soils due copper toxicity of the soil microbial community. The results of this thesis indicate that elevated levels of copper above 100 mg kg⁻¹ negatively impact the soil microbial community and may reduce the overall health of the soil. Biodegradation is a key mechanism for the degradation of atrazine and indoxacarb in the soil, so it is important that the health of the soil microbial community is maintained. Therefore, it is recommended that atrazine and indoxacarb are only applied to soils with a total copper concentration less than 100 mg kg⁻¹. This will protect the health of the soil microbial community and prevent the potential adverse effects of copper on the degradation of pesticide metabolites in the soil.

Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.

Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Also available on the Internet.

To reduce the uncertainty associated with pesticide fate model predictions on the large scale, a rapid method is needed that can generate sorption coefficients (Kd values) with sufficient spatial detail. The feasibility of near-infrared spectroscopy (NIRS) to act as such a method was examined, using weak-acidic (2,4-D), weak-basic (atrazine) and zwitterion (glyphosate) herbicides and the natural steroid estrogen (17β-estradiol). A total of 609 horizons in 140 soil profiles were collected in agricultural fields near Brandon, Manitoba and near Saskatoon, Saskatchewan. In both agricultural fields, Kd values in horizons generally increased in the order of 2,4-D < atrazine < 17β-estradiol < glyphosate. Soil organic carbon content (SOC) followed by the soil pH were the major factors controlling the sorption of 2,4-D, atrazine and 17β-estradiol but glyphosate showed very strong sorption to soil particles regardless of measured SOC and soil pH values. For the chemicals studied, Kd values decreased from A to C horizons regardless of the segment of the slope from which the soil samples were collected, with the exception of glyphosate that showed relatively large Kd values in B-horizons illuviated with clay. Both the Zeiss Corona and the Foss 6500 spectrophotometers produced significantly strong predictive models for soil properties and Kd values of 2,4-D, atrazine and 17β-estradiol. However, models for glyphosate Kd values were weak or not significant. Using a test set approach and either soil spectral or soil properties data as independent variables, partial least squares regressions were successfully developed to estimate Kd values for use in the Pesticide Root Zone Model (PRZM) to calculate the herbicide mass leached. The study concluded that the added benefit of NIRS will be most useful if the pesticides under study have small sorption potentials and short half-lives in soil. Regional approaches to predicting Kd values from NIRS spectral data can also be developed if the calibration model is derived by combining a set of fields where each has a similar statistical population characteristic in Kd values. / February 2016

Atrazine photochemical degradation in homogeneous phase using Fe(III)/UV/air system was studied. Two toxicity assessments, a Lemna minor growth inhibition test and a Daphnia magna acute immobilisation test, were employed to test potential toxicity of atrazine and its degradation products. The occurrence of atrazine in rivers from the Vltava River basin was evaluated from the analyses performed by Povodí Vltavy, State Enterprise.

Resumo: O uso de adjuvantes é adotado em todo o mundo, a fim de melhorar a eficácia das formulações de defensivos agrícolas, independente do tipo de alvo. Existem duas maneiras principais em que adjuvantes podem melhorar o desempenho final do produto. Em primeiro lugar, aumentando a quantidade de ingrediente ativo retido pelo alvo e, por outro, melhorando a sua absorção. O objetivo do presente trabalho foi avaliar os efeitos de óleos minerais e vegetais nas características físicas e químicas da calda de aplicação e na ação do herbicida atrazina (Gesaprim 500® SC). Os tratamentos estudados foram: atrazina, atrazina + Natur'l Óleo®; atrazina + Agr'Óleo®; atrazina + Assist® e testemunhas. Todos os adjuvantes foram acionados na proporção de 0.5% do volume da calda aplicada. As plantas indicadoras utilizadas nos estudos sobre os efeitos dos adjuvantes sobre a ação da atrazina foram: Ipomoea grandifolia,Brachiaria plantaginea, Merremia cissoides e Euphorbia heterophylla. Os parâmetros estudados foram: tensão superficial, pH, efeito do tempo de preparo da calda e do pH sobre a tensão superficial, evaporação da calda, tamanho de gotas, eficácia de controle de plantas daninhas, influência da chuva no controle da atrazina e a velocidade de absorção da atrazina com o uso do fluorômetro. O delineamento experimental utilizado foi em bloco casualizados, com quatro repetições. Portanto com os resultados obtidos pode-se concluir que uso de óleos vegetais ou minerais influenciou positivamente nas características físicas e químicas da calda de aplicação agindo diretamente na ação de herbicidas apresentando uma alta eficiência de controle das espécies estudadas / Abstract: The adjuvants are used all over the world in order to improve the effectiveness of the herbicides formulations, independent of target. There are two main ways in which adjuvants can improve the performance of the final product. First, increasing the amount of active ingredient retained by the target and secondly, promoting its absorption. The objective of this study was to evaluate the effects of mineral and vegetable oils in physical and chemical characteristics of the application and action of the herbicide Gesaprim 500® (atrazine). The treatments studied were: atrazine; atrazine + Natur'l Óleo®; atrazine + Agr'Óleo®; atrazine + Assist® and check. All adjuvants were used at a rate of 0.5% of the volume of spray applied. The indicator plants used in studies on the effects of adjuvants on the action of atrazine were: Ipomoea grandifolia, Brachiaria plantaginea, Merremia cissoides and Euphorbia heterophylla. The parameters studied were: surface tension, pH, effect of time preparing the solutions and pH on surface tension, evaporation of the solution, droplet size, effective weed control, rain influence in weed control, the active ingredient absorption velocity using the fluorometer method. The experimental design was randomized blocks with four replications. So with the results we can conclude that the use of vegetable or mineral oils had a positive influence on physical and chemical characteristics and at the application acts the treatments showed a highly efficient control of the studied species / Orientador: Edivaldo Domingues Velini / Coorientador: Eduardo Negrisoli / Banca: Augusto Guerreiro Fontoura Costa / Banca: Caio Antonio Carbonari / Mestre

Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós–Graduação em Oceanografia Biológica, Instituto de Oceanografia, 2012. / Submitted by Cristiane Gomides (cristiane_gomides@hotmail.com) on 2013-11-18T15:23:39Z No. of bitstreams: 1 anderson.pdf: 2147843 bytes, checksum: 1fd27dd610099252c3f5f6c1e2b14fed (MD5) / Approved for entry into archive by Angelica Miranda (angelicacdm@gmail.com) on 2013-11-18T19:21:19Z (GMT) No. of bitstreams: 1 anderson.pdf: 2147843 bytes, checksum: 1fd27dd610099252c3f5f6c1e2b14fed (MD5) / Made available in DSpace on 2013-11-18T19:21:19Z (GMT). No. of bitstreams: 1 anderson.pdf: 2147843 bytes, checksum: 1fd27dd610099252c3f5f6c1e2b14fed (MD5) Previous issue date: 2012 / A poluição aquática em zonas costeiras é crescente, exigindo cada vez mais o uso de ferramentas alternativas para seu monitoramento. Dentre estas, as de maior potencial são os biomarcadores, que são medidas biológicas capazes de expressar exposição ou efeito deletério de contaminantes. Porém, a falta de informação sobre respostas de biomarcadores a contaminantes em concentrações ambientalmente relevantes constitui empecilho ao emprego destas ferramentas. Neste trabalho foram analisados os efeitos de três contaminantes em diversos biomarcadores usualmente utilizados em estudos de avaliação ambiental. Os contaminantes testados foram cobre (metal), atrazina (herbicida) e fenantreno (hidrocarboneto policíclico aromático). Os biomarcadores avaliados foram atividades enzimáticas (superóxido dismutase, catalase, glutationa redutase e glutationa s-transferase), concentração de metalotioneínas, espécies reativas de oxigênio, capacidade antioxidante, peroxidação lipídica, quebras na fita de DNA, freqüência de células micronucleadas e de anomalias nucleares, e composição iônica corporal. Os três contaminantes demonstraram potencial para afetar os biomarcadores avaliados, porém cada um afetou distintamente os grupos de biomarcadores. O efeito do cobre foi caracterizado por um elevado potencial de geração de estresse oxidativo em brânquias, fígado e músculo, além de causar dano genético através da quebra da fita de DNA e clastogenicidade. A atrazina aumentou a atividade da glutationa s-transferase, causou estresse oxidativo branquial e danos genéticos não detectáveis no ensaio cometa. Por fim, o fenantreno gerou estresse oxidativo muscular, sendo a maioria dos danos possivelmente relacionada à geração de metabólitos reativos durante sua degradação, resultando em elevada genotoxicidade e citotoxicidade, bem como perturbações de sistemas enzimáticos e da fisiologia do animal. / Aquatic pollution in coastal areas is increasing, demanding the use of alternative tools for its adequate monitoring. Among them, biomarkers are those showing higher potential for practical use. They are biological measurements capable of detecting the exposure and effects of contaminants. However, the lack of information on the response of biomarkers to contaminants at environmentally relevant levels is a constraint for the employment of these tools in monitoring programs. In the present study, the effects of three contaminants on several biomarkers commonly employed in environmental analyses were evaluated. Contaminants tested were copper (metal), atrazine (herbicide) and phenanthrene (polycyclic aromatic hydrocarbon). Biomarkers evaluated were enzyme activities (superoxide dismutase, catalase, glutathione reductase and glutathione s-transferase), metallothioneins concentration, reactive oxygen species, antioxidant capacity, lipid peroxidation, DNA strand-breaks, micronucleated cells and nuclear anomalies frequencies, and whole-body ion composition. The three contaminants showed potential to affect the biomarkers evaluated. However, each contaminant affected distinctly the groups of biomarkers. Copper effect was characterized by a elevated potential for oxidative stress generation in gills, liver and muscle. It also induced genetic damage (DNA strand-breaks) and clastogenicity. Atrazine increased glutathione stransferase activity, caused oxidative stress in gills and genetic damage non detectable by the Comet assay. Finally, phenanthrene induced oxidative stress in muscle, being most of the damage likely associated with the generation of reactive metabolites during the contaminant degradation process. Exposure to phenanthrene resulted in elevated genotoxicity and cytotoxicity, as well as perturbations of the enzymatic systems and the whole-animal physiology.

Submitted by Erika Demachki (erikademachki@gmail.com) on 2014-12-01T20:04:13Z No. of bitstreams: 2 Dissertação - Keyle Borges e Silva Monteiro - 2013.pdf: 4439277 bytes, checksum: f4c76f010f6dd19a6ec56bcf424fcc5f (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Erika Demachki (erikademachki@gmail.com) on 2014-12-01T20:04:46Z (GMT) No. of bitstreams: 2 Dissertação - Keyle Borges e Silva Monteiro - 2013.pdf: 4439277 bytes, checksum: f4c76f010f6dd19a6ec56bcf424fcc5f (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-12-01T20:04:46Z (GMT). No. of bitstreams: 2 Dissertação - Keyle Borges e Silva Monteiro - 2013.pdf: 4439277 bytes, checksum: f4c76f010f6dd19a6ec56bcf424fcc5f (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-08-12 / 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.