Individuals are exposed to chemical mixtures while carrying out everyday tasks, with unknown risk associated with exposure. Given the number of resulting mixtures it is not economically feasible to identify or characterize all possible mixtures. When complete dose-response data are not available on a (candidate) mixture of concern, EPA guidelines define a similar mixture based on chemical composition, component proportions and expert biological judgment (EPA, 1986, 2000). Current work in this literature is by Feder et al. (2009), evaluating sufficient similarity in exposure to disinfection by-products of water purification using multivariate statistical techniques and traditional hypothesis testing. The work of Stork et al. (2008) introduced the idea of sufficient similarity in dose-response (making a connection between exposure and effect). They developed methods to evaluate sufficient similarity of a fully characterized reference mixture, with dose-response data available, and a candidate mixture with only mixing proportions available. A limitation of the approach is that the two mixtures must contain the same components. It is of interest to determine whether a fully characterized reference mixture (representative of the random process) is sufficiently similar in dose-response to a candidate mixture resulting from a random process. Four similarity measures based on Euclidean distance are developed to aid in the evaluation of sufficient similarity in dose-response, allowing for mixtures to be subsets of each other. If a reference and candidate mixture are concluded to be sufficiently similar in dose-response, inference about the candidate mixture can be based on the reference mixture. An example is presented demonstrating that the benchmark dose (BMD) of the reference mixture can be used as a surrogate measure of BMD for the candidate mixture when the two mixtures are determined to be sufficiently similar in dose-response. Guidelines are developed that enable the researcher to evaluate the performance of the proposed similarity measures.

A research report submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the Degree of Master of Science in Engineering, 2016 / Previously undermined areas pose a significant challenge to mining by opencast due to the risk of sinkhole occurrence. In order to optimise reserve utilisation as well as safeguard personnel and equipment there was need to develop a “Sinkhole Prediction Model” to assist in the prediction of areas prone to sinkhole formation. The aim of this research therefore was to develop a “Sinkhole prediction tool” with a view to pre-identifying areas of potential sinkhole hazard to inform better controls to assist in mining these areas safely. This was done utilising the current Hill (1996) caving height method culminating in the development of a hazard index model dividing the mining zones into high and low hazard. These areas were colour coded Red (High hazard) and Green (Low Hazard). The “Sinkhole Prediction Model” evolved to include over hundred sinkhole incidences that were statistically analysed to firm up on the robustness of the Prediction Model capabilities. The Hill (1996) caving height formula was discounted after the statistical analysis indicated that a good prediction model lies in the interrogation of site specific data. The outcome of the work conducted in this research report indicated a 97% correlation between the refined “Sinkhole Prediction Model” and the actual sinkhole occurrence at the Anglo American case study area (Mine X). Various refinements inclusive of lithological assessments, blast and drilling reconciliations as well as the implementation of the roughening up quality audits led to the implementation of a robust sinkhole management process that has managed to consistently assist in safeguarding equipment and personnel thus allowing for coal extraction optimisation in areas that could have been written off due to the sinkhole hazard. This risk can only be eliminated by mining the areas with the sinkhole risk. Currently the method is being impacted by significant roughening up cost incurred in a drive to make the areas safe to allow for coal extraction. The roughening up process on average costs R3.5 million per sinkhole and is a function of the number of sinkholes found, which translates to an equivalent cost of R7 / sales tonne. The current sinkhole prediction model being employed in deficient in that it cannot pinpoint the actual location of the void in the area previously undermined by bord and pillar and this is a great limitation of this report. Various geophysical techniques were pursued to assist in the precise identification of the actual sinkhole spatially. This process was aimed to reduce the roughening up cost (entire block stabilisation) as opposed to targeted sinkhole excavation and stabilisation. This process proved futile as the void identification systems are highly incapable of identifying the voids / iv sinkholes spatially (x, y and z coordinates) to assist targeted sinkhole treatment as a result of the following:  System inability to penetrate areas comprised of highly conductive strata such as clays.  Inability to distinguish between the underground voids and geological anomalies such as dykes.  Not suitable for penetrating wet strata.  Impacted by noise interference from mining machinery. The major result of this research is the establishment of a site specific “Sinkhole Prediction Model” that can generate hazard plans in real time thus informing the management on areas associated with a potential sinkhole hazard. The hazard plans can be generated timely and decisions made to facilitate safe coal extraction in areas of high sinkhole hazard. This has culminated in a robust sinkhole management process within the group that has managed to eliminate the risk of personnel and equipment exposure at Mine X. The roughening up process is accepted as the primary sinkhole mitigation or rehabilitation process with the need to work towards reducing the roughening up costs through development of the tool capable of precisely identifying the voids routinely to facilitate targeted rehabilitation. Significant research is required in this area as the mining environment is comprised of strata that currently cannot support the use of real time void identification to facilitate targeted void identification and rehabilitation. There is also merit in the future to formulate the database capable of assisting in the prediction of sinkholes in the Witbank coalfield as well as assist in robust management of mining boundaries across the different mining houses. The system implemented at Mine X is currently being deployed to other operations in the group where modification will be made to match the site specific conditions. Future research into understanding the sinkhole occurrence dynamics is quite crucial if targeted rehabilitation is to be achieved for cost reduction and mining sustainability. A combination of the understanding of the sinkhole occurrence driving mechanisms in conjunction with use of modelling packages such as ELFEN (a hybrid Modelling) tool will go a long way in enhancing the development of precise sinkhole prediction point in space.

Conventional ecotoxicological tests (forced exposure) are an important tool when what is sought are the possible acute and chronic effects of environmental pollutants on each individual that is exposed. The disadvantage of this approach lies in the fact that the organisms are kept enclosed within containers of the same concentration for several hours and / or days. The forced exposure test has no ecological relevance when the modeled environment exhibits a contamination gradient and organisms can move along this gradient. In many aquatic ecosystems, it is common to observe a contamination gradient, with concentrations decreasing with distance from the discharge zone, so that organisms do not necessarily exhibit continuous and forced exposure to the contaminant. The objective of this work was to analyze how aquatic pollutants (e.g Triclosan, Bisphenol, Atrazine and Copper) influence the dispersion / habitat selection pattern of two species of fish: Poecilia reticulata and Danio rerio, using a static system (non-forced exposure) with several compartments, forming a gradient of contamination with the compound to be analyzed. All pollutants tested triggered an avoidance response in fish at environmentally relevant concentrations. The concentrations that caused avoidance on the organisms are lower than those that cause sub-lethal effects on aquatic organisms, including fish. We also find in one of our approaches the potential for the formation of a chemical barrier (habitat fragmentation) by the release of pollutants into the water bodies, reducing the migration potential of aquatic organisms. Finally, one of the most important findings is the interaction of the species with each other when exposed to a pollution gradient. In this case, the presence of one species interfered in the distribution of the other (reduction of the migration potential), when both were in the same system. Thus, the non-forced approach demonstrates to be a powerful tool in the evaluation of environmental risk, complementary to the traditional ecotoxicological tests / Os testes ecotoxicológicos convencionais (exposição forçada) são uma ferramenta importante quando o que se busca são os possíveis efeitos agudos e crônicos dos poluentes ambientais sobre cada indvíduo que é exposto. A desvantagem dessa abordagem está no fato de que os organismos são mantidos enclausurados dentro de recipientes com uma mesma concentração por várias horas e/ou dias. O teste de exposição forçada não tem relevância ecológica quando o ambiente modelado apresenta um gradiente de contaminação e os organismos podem se mover ao longo deste gradiente. Em muitos ecossistemas aquáticos, é comum observar um gradiente de contaminação, com as concentrações diminuindo com a distância da zona de descarga, de modo que os organismos não apresentam obrigatoriamente uma exposição contínua e forçada ao contaminante. Desta forma, este trabalho teve como objetivo a análise de como os poluentes aquáticos (e.g. Triclosan, Bisfenol, Atrazina e Cobre) influenciam o padrão de dispersão / seleção de habitat por duas espécies de peixes: Poecilia reticulate e Danio rerio, utilizando um sistema estático (não forçado) com vários compartimentos, formando um gradiente de contaminação com o composto a ser analisado. Todos os poluentes testados dispararam uma resposta de fuga nos peixes em concentrações ambientalmente relevantes. As concentrações que causaram a fuga dos organismos são menores do que aquelas que causam efeitos sub-letais em organismos aquáticos, incluindo peixes. Encontramos também em uma de nossas abordagens o potencial de formação de uma barreira quimica (fragmentação de habitat) pela liberação de poluentes nos corpos hídricos, reduzindo o potencial de migração dos organismos aquáticos. Por fim, um dos achados mais importantes está na interação das espécies entre si quando expostas a um gradiente de poluição. Nesse caso, a presença de uma espécie interferiu na distribuição da outra (redução do potencial de migração), quando ambas se encontravam no mesmo sistema. Sendo assim, a abordagem não forçada demonstra ser uma ferramenta poderosa na avaliação de risco ambiental, complementar aos testes ecotoxicológicos tradicionais

A qualidade do ar nas áreas urbanas e industriais tende a apresentar concentrações indesejáveis de contaminantes, sem que haja um sistema abrangente de monitoramento, dada a sofisticação dos métodos físico-químicos convencionais, que requerem custos elevados de implantação, operação e manutenção, custos estes, que podem ser minimizados pela adoção de metodologia complementar de biomonitoramento. O biomonitoramento é um método experimental que permite avaliar a resposta de organismos vivos à poluição, oferecendo vantagens como: custos reduzidos, eficiência para o monitoramento de áreas amplas e por longos períodos de tempo e, também, avaliação de elementos químicos em baixas concentrações ambientais. As medidas e registros efetuados por redes convencionais de monitoramento da qualidade do ar permitem verificar se normas e limites estabelecidos ou recomendados pela legislação, agências ambientais e órgãos de promoção da saúde humana estão sendo respeitados. Entretanto, tais medições não permitem conclusões imediatas sobre as conseqüências de poluentes nos seres vivos. Assim, o biomonitoramento deve ser considerado como um método complementar na análise de poluentes, podendo constituir-se em um terceiro sistema de informações, além dos inventários de emissões e de concentrações ambientais. O presente trabalho teve por objetivo identificar, por meio de revisão sistemática de literatura desenvolvida por dois revisores independentes, espécies vegetais (vasculares, musgos e líquens) utilizadas como bioindicadores, referente ao período de janeiro de 1997 a junho de 2003, em estudos experimentais e observacionais, associando-as a poluentes atmosféricos. De um total de 4547 trabalhos científicos sobre bioindicadores, foram pré-selecionados 279 estudos referentes ao uso de vegetais bioindicadores de poluição atmosférica, publicados nos idiomas inglês, espanhol e português. Estes trabalhos foram analisados pela aplicação de dois testes de relevância, sendo selecionadas 240 referências e obtidos 154 estudos na íntegra. Deste total, foram incluídos, após aplicação dos dois testes de relevância, 126 trabalhos científicos, sobre o tema considerado, realizados em 34 diferentes países. Constatou-se que o uso da metodologia de revisão sistemática permitiu levantar o conhecimento das experiências acadêmicas nesta área de estudo, ampliando o conhecimento sobre esse tema. Os resultados ainda revelaram a utilização de 112 espécies vegetais, sendo 64 espécies pertencentes à divisão Angiospermae; 11 espécies da divisão Coniferophyta; 22 espécies de líquens e 15 espécies de musgos, relacionadas ao monitoramento de um ou mais dos seguintes poluentes atmosféricos: metais pesados, ozônio, material particulado, dióxido de enxofre, óxidos de nitrogênio, monóxido de carbono, fluoretos, compostos orgânicos voláteis e hidrocarbonetos. Constatou-se, assim, a existência de uma quantidade significativa de estudos dessa natureza, principalmente nos países europeus, onde está implantado o projeto EUROBIONET de biomonitoramento de poluição atmosférica, baseado na padronização de ensaios e biomonitores, desde o ano 2000. Tendo em vista que determinados bioindicadores já estão consagrados ou mesmo validados para o monitoramento de poluentes atmosféricos específicos, considera-se ser possível a instalação de uma rede de biomonitoramento ambiental no Estado de São Paulo, a partir de um trabalho conjunto e coordenado entre universidades, municípios e agência de proteção ambiental, associada à rede existente de monitoramento convencional da qualidade do ar. Tal iniciativa permitirá que mais um passo seja dado na universalização dos cuidados com os ambientes natural e social, promovendo e garantindo melhorias no padrão de qualidade de vida das sociedades atuais e futuras. / Air quality in urban and industrial areas tends to present undesirable concentrations of contaminants, without the availability of a broad monitoring system, given the sophistication of conventional physical-chemical methods, which require high expenditure for implantation, operation and maintenance. These costs can be reduced by the adoption of the complementary biomonitoring methodology. Biomonitoring is an experimental methodology that allows us to evaluate the response of living organisms to pollution, including advantages such as: reduced costs; efficiency to monitor large areas over long periods of time; evaluation of chemical elements in low environmental concentrations. Measurements and registers by conventional air quality monitoring networks allow us to verify whether the standards and limits set by legislation, environmental agencies and human health promotion bodies are being respected. However, these measurements do not allow for immediate conclusions about the consequences of polluting agents for human beings. Thus, biomonitoring must be considered a complementary method for analyzing pollutant agents and can constitute a third information system, besides emission and environmental concentration inventories. This study aimed to identify, by means of a systematic literature review carried out by two peer independent reviewers, vegetal species (vascular, moss and lichen) that are used as bioindicators, in the period from January 1997 to June 2003, in experimental and observational studies, linking them up with atmospheric pollutant agents. Out of a total of 4,547 scientific studies on bioindicators, 279 studies about the use of vegetal atmospheric pollution indicators were preselected, published in English, Spanish and Portuguese. These studies were analyzed by means of two relevancy tests, resulting in the selection of 240 references and 154 full studies. Out of this total, after applying the two relevancy tests, we included 126 scientific studies from 34 different countries. The systematic review methodology allowed us to survey the knowledge resulting from academic experiments in this field of study, thus broadening the knowledge related to that theme. Results disclosed the use of 111 vegetal species, 63 of which belonged to the Angiospermae group; 11 to the Coniferophyta group; 15 moss species and 22 lichen species, related to the monitoring of one or more of the following atmospheric polluting agents: heavy metals, ozone, particles, sulfur dioxide, nitrogen oxides, carbon monoxide, fluorides, volatile organic compounds. Thus, we observed that there is a significant amount of this kind of studies, mainly in European countries, where the EUROBIONET project for biomonitoring atmospheric pollution has been implanted since 2000, based on test and biomonitor standardization. In view of the fact that certain bioindicators are already acclaimed or even validated for monitoring specific atmospheric polluting agents, we believe it is possible to install an environmental biomonitoring network in São Paulo State, starting from a joint and coordinated effort among universities, municipalities and the environmental protection agency, in cooperation with the existing conventional air quality monitoring network. This initiative will allow for another step in the universalization of natural and social environment care, promoting and guaranteeing improvement in the quality of life of current and future societies.

Frames são dispositivos cognitivos que organizam os sentidos da vida cotidiana. Enquadrar um risco ambiental é fazer mais saliente algumas de suas possibilidades, promovendo uma ou outra interpretação. A dissertação examina como a pauta dos transgênicos foi enquadrada pelos portais Estadão Digital <estadao.com.br> e Folha de S. Paulo <folha.uol.com.br> no período de 1998 a 2015. Para tanto, mediante a análise dos elementos textuais dos artigos (metáforas, escolhas de palavras e argumentos), 1.396 notícias foram classificadas em um dos seguintes frames de notícia: progresso, prospecto econômico, ética, caixa de Pandora, descontrole, natureza, responsabilidade pública e globalização. Os achados revelam que o frame predominante foi \"responsabilidade pública\", especialmente durante o biênio 2003/04 que antecedeu a sanção da \"Lei da Biossegurança\" em 2005. Mas antes de comunicar informações plurais, equilibradas, relacionando antecedentes e pressupostos, avaliando implicações e examinando alternativas e critérios de comparação, a mídia paulista tratou muito mais dos aspectos associados às polêmicas e conflitos políticos nacionais / Frames are cognitive devices that organize the meanings of everyday life. To frame a certain risk is to do more prominent some of its possibilities, promoting one or another interpretation. The research examines how the agenda of transgenic organisms has been framed by the Brazilian online newspapers Estadão Digital <estadao.com.br> and Folha de S. Paulo <folha.uol.com.br> from 1998 to 2015. To do so, an analysis of the internal textual elements (metaphors, selection of words and arguments) presented in the articles was done, resulting in 1.396 classified news according to one of the following news frames: progress, economic prospect, ethics, Pandora\'s box, runaway technology, nature/nurture, public accountability and globalization. The findings suggest that \"public accountability\" was the most frequently frame, especially during the years 2003/04, which preceded the sanction of the \"Biosafety Law\", in March 2005. Thus, despite communicating plural and balanced information, relating antecedent and assumptions, evaluating and examining alternatives criteria, the state of São Paulo\'s press has been dealing much more with the controversies and political conflict aspects of the subject

The environment is increasingly recognised as a key player in the emergence and mobilisation of antibiotic resistance, which negatively impacts human health, healthcare systems, and farming practices worldwide. Recent work has demonstrated concentrations of antibiotics in the natural environment may select for resistance in situ, but a scarcity of meaningful data has prevented rigorous environmental risk assessment of antibiotics. Without such data, mitigation strategies, such as improved antibiotic stewardship or environmental discharge limits, cannot be effectively designed or implemented. This thesis designed and developed two methods for determining effect concentrations of antibiotics in complex microbial communities, thereby generating a significant amount of data to address this knowledge gap. Minimal selective concentrations (MSCs) were determined in long term selection experiments for four classes of antibiotic at concentrations as low as 0.4 μg/L, which is below many measured environmental concentrations. Lowest observed effect concentrations were determined using a short term, growth based assay which were highly predictive of MSCs. A novel finding was significant selection for cefotaxime resistance occurred at a wide range of antibiotic concentrations, from 125 μg/L - 64 mg/L, which has important clinical implications. Determination of MSC in single species assays was also shown to be a poor predictor of MSC in a complex microbial community. Co-selection for antimicrobial resistance was demonstrated in selection experiments and through improved understanding of class 1 integron evolution, assessing selective effects on resistance gene acquisition using a novel PCR method and next-generation sequencing. In the final study, a novel resistance determinant (UDP-galactose 4-epimerase) conferring cross-resistance to biocides and antibiotics was discovered, providing a target for further study. These findings indicate selection and co-selection for antimicrobial resistance is likely to occur in the environment, and provides the means to rapidly generate further data to aid in the development of appropriate mitigation strategies.

Frames são dispositivos cognitivos que organizam os sentidos da vida cotidiana. Enquadrar um risco ambiental é fazer mais saliente algumas de suas possibilidades, promovendo uma ou outra interpretação. A dissertação examina como a pauta dos transgênicos foi enquadrada pelos portais Estadão Digital <estadao.com.br> e Folha de S. Paulo <folha.uol.com.br> no período de 1998 a 2015. Para tanto, mediante a análise dos elementos textuais dos artigos (metáforas, escolhas de palavras e argumentos), 1.396 notícias foram classificadas em um dos seguintes frames de notícia: progresso, prospecto econômico, ética, caixa de Pandora, descontrole, natureza, responsabilidade pública e globalização. Os achados revelam que o frame predominante foi \"responsabilidade pública\", especialmente durante o biênio 2003/04 que antecedeu a sanção da \"Lei da Biossegurança\" em 2005. Mas antes de comunicar informações plurais, equilibradas, relacionando antecedentes e pressupostos, avaliando implicações e examinando alternativas e critérios de comparação, a mídia paulista tratou muito mais dos aspectos associados às polêmicas e conflitos políticos nacionais / Frames are cognitive devices that organize the meanings of everyday life. To frame a certain risk is to do more prominent some of its possibilities, promoting one or another interpretation. The research examines how the agenda of transgenic organisms has been framed by the Brazilian online newspapers Estadão Digital <estadao.com.br> and Folha de S. Paulo <folha.uol.com.br> from 1998 to 2015. To do so, an analysis of the internal textual elements (metaphors, selection of words and arguments) presented in the articles was done, resulting in 1.396 classified news according to one of the following news frames: progress, economic prospect, ethics, Pandora\'s box, runaway technology, nature/nurture, public accountability and globalization. The findings suggest that \"public accountability\" was the most frequently frame, especially during the years 2003/04, which preceded the sanction of the \"Biosafety Law\", in March 2005. Thus, despite communicating plural and balanced information, relating antecedent and assumptions, evaluating and examining alternatives criteria, the state of São Paulo\'s press has been dealing much more with the controversies and political conflict aspects of the subject

Um novo herbicida da classe das sulfonamida-triazolopirimidinas do grupo dos herbicidas inibidores da síntese do acetolactato (ALS) encontra-se em desenvolvimento. Trata-se de um herbicida ionizável, com caráter ácido fraco (pKa = 4,67). Sua solubilidade em água depende do pH do meio, trata-se de uma molécula hidroliticamente estável, sendo bastante suscetível à fotodegradação em meio aquoso. A fotodegradação em solo não é significativa. Neste estudo, avaliaram-se os potenciais de sorção, lixiviação e dissipação deste herbicida em quatro solos brasileiros: Gleissolo Melânico Alumínico típico (GMa), Latossolo Vermelho Distroférrico típico (LVdf), Neossolo Quartzarênico órtico típico (RQ) e Argissolo Vermelho eutroférrico chernossólico (PV). No estudo de sorção, as isotermas foram ajustadas através do modelo de Freundlich e os valores dos coeficientes de sorção (Kd) variaram de 0,5 a 22,4 mL g-1 indicando um potencial de sorção baixo a moderado. No estudo de mobilidade, nenhuma radioatividade foi observada nos lixiviados coletados até 48 horas nos solos GMa, LVdf e PV, no solo RQ detectou-se 2 % do aplicado. Os resultados de mobilidade comparativos sugerem que o herbicida seja classificado como moderadamente móvel pelo critério do Fator de Mobilidade Relativa (FMR) em todos os solos estudados. No estudo de dissipação, a taxa de transformação do herbicida em condições aeróbicas além da natureza e taxa de formação e declínio de produtos de transformação do herbicida foram acessados. Um modelo exponencial de primeira ordem foi utilizado para ajustar a dissipação do herbicida nos solos. A meia-vida do herbicida foi de 22, 15, 110 e 39 nos solos GMa, LVdf, RQ e PV, respectivamente. Uma avaliação de risco ambiental inicial do herbicida foi acessada pelo uso do método dos quocientes (RQ risk quotient), sendo risco = exposição/efeito. A exposição é representada pela Concentração Ambiental Esperada (CAE) e foi avaliada nos compartimentos ambientais solo, águas superficiais e águas subterrâneas. Os cálculos de CAE foram obtidos por avaliação de cenários simples do tipo pior caso nos diferentes compartimentos e pelo emprego dos modelos matemáticos GENEEC e SCIGROW para águas superficiais e subterrâneas, respectivamente. Na estimativa do efeito, usou-se os valores limite (endponts, exemplos: EC50, NOEC) disponíveis para diferentes organismos representantes dos diferentes compartimentos ambientais estudados. O resultado do quociente exposição/efeito foi comparado com os níveis de preocupação (LOC level of concern) empregados pelo EPA para avaliação do potencial risco do uso deste herbicida para os diferentes organismos representativos dos diferentes compartimentos ambientais estudados. Assumindo o pior cenário (menor valor de Kd e maior valor de DT50), as estimativas das CAEs foram baixas e iguais a 0,024 mg kg-1 no solo, a 0,0008 mg L-1 na água superficial e a 0,04 \'mü\' L-1 na água subterrânea. Os valores de RQ obtidos (< 1 e inferiores aos respectivos LOCs) indicaram baixo potencial de risco do uso deste herbicida para os diferentes organismos, representativos dos diversos compartimentos ambientais estudados / A new active ingredient of the triazolopyrimidine sulfonamide herbicide class from the ALS group is under development. This is an ionizable herbicide with weakly acidic behavior (pKa = 4.67). Its solubility in water depends on pH, it is a hydrolytically stable molecule, being highly susceptible to photodegradation in aqueous medium. The photodegradation in soil is not significant. This study evaluated the potential of sorption, leaching and dissipation of this herbicide in four Brazilian soils: Gleissolo Melânico Alumínico típico (GMa), Latossolo Vermelho Distroférrico típico (LVdf), Neossolo Quartzarênico órtico típico (RQ) e Argissolo Vermelho eutroférrico chernossólico (PV). In the study of sorption isotherms were fitted using the Freundlich model and the values of sorption coefficients (Kd) ranged from 0.5 to 22.4 g mL-1 indicating a potential low to moderate sorption. In the study of mobility, no radioactivity was observed in the leachate collected until 48 hours in soils GMa, LVdf and PV, in the soil RQ was detected about 2% of applied radioactivity. The results of comparative mobility suggest that the herbicide is classified as moderately mobile by the criterion of Relative Mobility Factor (FMR) in all soils. In the study of dissipation, the rate of transformation of the herbicide under aerobic conditions and rate of formation and decline of transformation products of herbicide were accessed. A first order exponential model was used to adjust the dissipation of the herbicide in soils. The half-life of the herbicide was 22, 15, 110 and 39 days in soils GMa, LVdf, RQ and PV, respectively. An initial environmental risk assessment of the herbicide was accessed by using the method of quotient (RQ - risk quotient), RQ = exposure / effect. The exposure is represented by the Expected Environmental Concentration (EEC) and was evaluated in the environmental compartments soil, surface water and groundwater. EEC calculations were obtained by assessing simple scenarios such as \"worst case\" in the different compartments and the use of mathematical models GENEEC and SCIGROW to surface and groundwater assessments, respectively. In estimating the effect, endponts (examples: EC50, NOEC) available for different organisms representative from the different environmental compartments studied were used. The result of the quotient exposure / effect was compared to the \"levels of concern (LOC - level of concern) employed by the EPA to assess the potential risk from use of this herbicide for different organisms representing different environmental compartments studied. Assuming the worst case scenario (lower Kd value and higher value of DT50), the estimates of EECs were low and equal to 0.024 mg kg-1 soil, 0.0008 mg L-1 in surface water and 0.04 \'mü\' L-1 in the groundwater. The RQ values obtained (< 1 and below the respective LOCs) indicated low potential risk from use of this herbicide for different organisms, representative from different environmental compartments studied

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-08-29T17:27:52Z No. of bitstreams: 1 2013 - Miriam de Oliveira Bianchi.pdf: 4091539 bytes, checksum: 098efb42e3013339939d9ac91d1c741c (MD5) / Made available in DSpace on 2017-08-29T17:27:52Z (GMT). No. of bitstreams: 1 2013 - Miriam de Oliveira Bianchi.pdf: 4091539 bytes, checksum: 098efb42e3013339939d9ac91d1c741c (MD5) Previous issue date: 2013-02-27 / CAPES / The studies were carried part of the University of Coimbra - Portugal (Ecotoxicology Laboratory of Soil and Marine Research Institute-IMAR) and part of the premises of Embrapa Agrobiology - RJ. Originated from the beneficiation process aluminum, red mud (red mud), is generated from the refining of bauxite to produce alumina (Al2O3). Characterized as material of high alkalinity and large amount of salts associated with a huge amount produced annually by industries, the disposal of this material requires innumerous care. Accordingly, studies involving the analysis of the possible effects of the use and application of this material in the soil and on water sources emerge as key tools to minimize damage, either to the soil biological community, as water bodies. The aim of this study were assessing the intrinsic toxicity of red mud in soil organisms in artificial soil (Chapter I), and In Natural soil (Chapter II); end on aquatic organisms (Chapter III) as a result of leaching from contaminated soil solution. For ecotoxicological tests with soil organisms we studied two 'types' of waste, namely the red mud ?In Natura? and "Filtered" (with a 3% reduction in the content of Na). The concentrations tested were initially 0, 10, 20, 30, 40, 50, 60, 70, 80 and 90% of the residue ?In Natura?, and then set new doses of 0, 2.5, 5, 10, 20, 30 and 40% residual In Natura and also the "Filtered", and two types of soil collected in the same region (Po?os de Caldas - MG) where there are deposits of bauxite (Alcoa). In Chapter a considerable difference in the sensitivity of the test organisms was checked. The results showed that the red mud strongly inhibited reproduction for each. The high sodium concentration (Na+ = 18500.9 mg L-1) is probably the most deleterious factor for the reproduction of these species and has not been minimized toxicity by treatment applied to the sludge to reduce this salt. In Chapter II was observed an increase in the effects of the toxicity associated with natural soils. Still, the particular characteristics of each soil allow achieving particular outcomes for each environment tested. In Chapter III the residue ?In Natura? proved toxic to all aquatic organisms studied. / Os estudos foram realizados parte na Universidade de Coimbra ? Portugal (Laborat?rio de Ecotoxicologia de Solos e Instituto de Pesquisas Marinhas-IMAR) e parte nas instala??es da Embrapa Agrobiologia ? RJ. Originada do processo de beneficiamento do alum?nio, a lama vermelha (lama vermelha), ? gerada a partir do refino da bauxita para produ??o de alumina (Al2O3). Caracterizada como material de alta alcalinidade e grande quantidade de sais, associado ? grande quantidade produzida anualmente pelas ind?strias, o descarte desse material necessita de in?meros cuidados. Nesse sentido, estudos que envolvam a an?lise dos poss?veis efeitos da utiliza??o e aplica??o desse material tanto no solo como sobre as fontes de ?gua surgem como ferramentas fundamentais para minimizar danos, seja para a comunidade biol?gica do solo, como de corpos h?dricos. Os objetivos deste estudo foram avaliar a toxicidade intr?nseca da lama vermelha sobre organismos em solo artificial (Cap?tulo I); e em solos naturais (Cap?tulo II); e sobre organismos aqu?ticos (Cap?tulo III) em consequ?ncia da lixivia??o da solu??o do solo contaminado. Para os ensaios ecotoxicol?gicos com organismos de solo foram estudados dois ?tipos? do res?duo, a saber, a lama vermelha ?In Natura? e ?Filtrado? (com redu??o de 3% no teor de Na). As concentra??es ensaiadas foram inicialmente 0, 10, 20, 30, 40, 50, 60, 70, 80 e 90% do res?duo ?In Natura?, e em seguida, definidas novas doses de 0, 2,5, 5, 10, 20, 30 e 40% de res?duo ?In Natura? e tamb?m do ?Filtrado?, al?m de dois tipos de solo coletados na mesma regi?o (Po?os de Caldas - MG) onde ocorrem jazidas de bauxita. No Cap?tulo I foi verificada uma consider?vel diferen?a na sensibilidade dos organismos testados. Os resultados demonstraram que a lama vermelha inibiu fortemente a reprodu??o para cada um deles. O alto teor de s?dio (Na+ = 18500,9 mg L-1) ? provavelmente o fator mais delet?rio para a reprodu??o dessas esp?cies, n?o tendo sido minimizada a toxicidade pelo tratamento aplicado ? lama para a redu??o desse sal. No cap?tulo II foi poss?vel observar um incremento dos efeitos dessa toxicidade quando associado a solos naturais. Ainda assim, caracter?sticas particulares de cada solo permitem alcan?ar resultados particulares para cada ambiente testado. No Cap?tulo III o res?duo ?In Natura? mostrou-se t?xico para todos os organismos aqu?ticos estudados.

Um novo herbicida da classe das sulfonamida-triazolopirimidinas do grupo dos herbicidas inibidores da síntese do acetolactato (ALS) encontra-se em desenvolvimento. Trata-se de um herbicida ionizável, com caráter ácido fraco (pKa = 4,67). Sua solubilidade em água depende do pH do meio, trata-se de uma molécula hidroliticamente estável, sendo bastante suscetível à fotodegradação em meio aquoso. A fotodegradação em solo não é significativa. Neste estudo, avaliaram-se os potenciais de sorção, lixiviação e dissipação deste herbicida em quatro solos brasileiros: Gleissolo Melânico Alumínico típico (GMa), Latossolo Vermelho Distroférrico típico (LVdf), Neossolo Quartzarênico órtico típico (RQ) e Argissolo Vermelho eutroférrico chernossólico (PV). No estudo de sorção, as isotermas foram ajustadas através do modelo de Freundlich e os valores dos coeficientes de sorção (Kd) variaram de 0,5 a 22,4 mL g-1 indicando um potencial de sorção baixo a moderado. No estudo de mobilidade, nenhuma radioatividade foi observada nos lixiviados coletados até 48 horas nos solos GMa, LVdf e PV, no solo RQ detectou-se 2 % do aplicado. Os resultados de mobilidade comparativos sugerem que o herbicida seja classificado como moderadamente móvel pelo critério do Fator de Mobilidade Relativa (FMR) em todos os solos estudados. No estudo de dissipação, a taxa de transformação do herbicida em condições aeróbicas além da natureza e taxa de formação e declínio de produtos de transformação do herbicida foram acessados. Um modelo exponencial de primeira ordem foi utilizado para ajustar a dissipação do herbicida nos solos. A meia-vida do herbicida foi de 22, 15, 110 e 39 nos solos GMa, LVdf, RQ e PV, respectivamente. Uma avaliação de risco ambiental inicial do herbicida foi acessada pelo uso do método dos quocientes (RQ risk quotient), sendo risco = exposição/efeito. A exposição é representada pela Concentração Ambiental Esperada (CAE) e foi avaliada nos compartimentos ambientais solo, águas superficiais e águas subterrâneas. Os cálculos de CAE foram obtidos por avaliação de cenários simples do tipo pior caso nos diferentes compartimentos e pelo emprego dos modelos matemáticos GENEEC e SCIGROW para águas superficiais e subterrâneas, respectivamente. Na estimativa do efeito, usou-se os valores limite (endponts, exemplos: EC50, NOEC) disponíveis para diferentes organismos representantes dos diferentes compartimentos ambientais estudados. O resultado do quociente exposição/efeito foi comparado com os níveis de preocupação (LOC level of concern) empregados pelo EPA para avaliação do potencial risco do uso deste herbicida para os diferentes organismos representativos dos diferentes compartimentos ambientais estudados. Assumindo o pior cenário (menor valor de Kd e maior valor de DT50), as estimativas das CAEs foram baixas e iguais a 0,024 mg kg-1 no solo, a 0,0008 mg L-1 na água superficial e a 0,04 \'mü\' L-1 na água subterrânea. Os valores de RQ obtidos (< 1 e inferiores aos respectivos LOCs) indicaram baixo potencial de risco do uso deste herbicida para os diferentes organismos, representativos dos diversos compartimentos ambientais estudados / A new active ingredient of the triazolopyrimidine sulfonamide herbicide class from the ALS group is under development. This is an ionizable herbicide with weakly acidic behavior (pKa = 4.67). Its solubility in water depends on pH, it is a hydrolytically stable molecule, being highly susceptible to photodegradation in aqueous medium. The photodegradation in soil is not significant. This study evaluated the potential of sorption, leaching and dissipation of this herbicide in four Brazilian soils: Gleissolo Melânico Alumínico típico (GMa), Latossolo Vermelho Distroférrico típico (LVdf), Neossolo Quartzarênico órtico típico (RQ) e Argissolo Vermelho eutroférrico chernossólico (PV). In the study of sorption isotherms were fitted using the Freundlich model and the values of sorption coefficients (Kd) ranged from 0.5 to 22.4 g mL-1 indicating a potential low to moderate sorption. In the study of mobility, no radioactivity was observed in the leachate collected until 48 hours in soils GMa, LVdf and PV, in the soil RQ was detected about 2% of applied radioactivity. The results of comparative mobility suggest that the herbicide is classified as moderately mobile by the criterion of Relative Mobility Factor (FMR) in all soils. In the study of dissipation, the rate of transformation of the herbicide under aerobic conditions and rate of formation and decline of transformation products of herbicide were accessed. A first order exponential model was used to adjust the dissipation of the herbicide in soils. The half-life of the herbicide was 22, 15, 110 and 39 days in soils GMa, LVdf, RQ and PV, respectively. An initial environmental risk assessment of the herbicide was accessed by using the method of quotient (RQ - risk quotient), RQ = exposure / effect. The exposure is represented by the Expected Environmental Concentration (EEC) and was evaluated in the environmental compartments soil, surface water and groundwater. EEC calculations were obtained by assessing simple scenarios such as \"worst case\" in the different compartments and the use of mathematical models GENEEC and SCIGROW to surface and groundwater assessments, respectively. In estimating the effect, endponts (examples: EC50, NOEC) available for different organisms representative from the different environmental compartments studied were used. The result of the quotient exposure / effect was compared to the \"levels of concern (LOC - level of concern) employed by the EPA to assess the potential risk from use of this herbicide for different organisms representing different environmental compartments studied. Assuming the worst case scenario (lower Kd value and higher value of DT50), the estimates of EECs were low and equal to 0.024 mg kg-1 soil, 0.0008 mg L-1 in surface water and 0.04 \'mü\' L-1 in the groundwater. The RQ values obtained (< 1 and below the respective LOCs) indicated low potential risk from use of this herbicide for different organisms, representative from different environmental compartments studied