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Does normal developmental expression of psychosis combine with environmental risk to cause persistence of psychosis? A psychosis proneness-persistence modelCougnard, Audrey, Marcelis, Machteld, Myin-Germeys, Inez, De Graaf, Ron, Vollebergh, Wilma A. M., Krabbendam, Lydia, Lieb, Roselind, Wittchen, Hans-Ulrich, Henquet, Cécile, Spauwen, Janneke, Van Os, Jim 29 January 2013 (has links) (PDF)
Background. Research suggests that low-grade psychotic experiences in the general population are a common but transitory developmental phenomenon. Using two independent general population samples, the hypothesis was examined that common, non-clinical developmental expression of psychosis may become abnormally persistent when synergistically combined with developmental exposures that may impact on behavioural and neurotransmitter sensitization such as cannabis, trauma and urbanicity.
Method. The amount of synergism was estimated from the additive statistical interaction between baseline cannabis use, childhood trauma and urbanicity on the one hand, and baseline psychotic experiences on the other, in predicting 3-year follow-up psychotic experiences, using data from two large, longitudinal, random population samples from the Netherlands [The Netherlands Mental Health Survey and Incidence Study (NEMESIS)] and Germany [The Early Developmental Stages of Psychopathology (EDSP) study].
Results. The 3-year persistence rates of psychotic experiences were low at 26% in NEMESIS and 31% in EDSP. However, persistence rates were progressively higher with greater baseline number of environmental exposures in predicting follow-up psychotic experiences (χ2=6·9, df=1, p=0·009 in NEMESIS and χ2=4·2, df=1, p=0·04 in EDSP). Between 21% and 83% (NEMESIS) and 29% and 51% (EDSP) of the subjects exposed to both environmental exposures and psychotic experiences at baseline had persistence of psychotic experiences at follow-up because of the synergistic action of the two factors.
Conclusion. The findings suggest that environmental risks for psychosis act additively, and that the level of environmental risk combines synergistically with non-clinical developmental expression of psychosis to cause abnormal persistence and, eventually, need for care.
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Soft computing approaches to uncertainty propagation in environmental risk mangementKumar, Vikas 19 June 2008 (has links)
Real-world problems, especially those that involve natural systems, are complex and composed of many nondeterministic components having non-linear coupling. It turns out that in dealing with such systems, one has to face a high degree of uncertainty and tolerate imprecision. Classical system models based on numerical analysis, crisp logic or binary logic have characteristics of precision and categoricity and classified as hard computing approach. In contrast soft computing approaches like probabilistic reasoning, fuzzy logic, artificial neural nets etc have characteristics of approximation and dispositionality. Although in hard computing, imprecision and uncertainty are undesirable properties, in soft computing the tolerance for imprecision and uncertainty is exploited to achieve tractability, lower cost of computation, effective communication and high Machine Intelligence Quotient (MIQ). Proposed thesis has tried to explore use of different soft computing approaches to handle uncertainty in environmental risk management. The work has been divided into three parts consisting five papers. In the first part of this thesis different uncertainty propagation methods have been investigated. The first methodology is generalized fuzzy α-cut based on the concept of transformation method. A case study of uncertainty analysis of pollutant transport in the subsurface has been used to show the utility of this approach. This approach shows superiority over conventional methods of uncertainty modelling. A Second method is proposed to manage uncertainty and variability together in risk models. The new hybrid approach combining probabilistic and fuzzy set theory is called Fuzzy Latin Hypercube Sampling (FLHS). An important property of this method is its ability to separate randomness and imprecision to increase the quality of information. A fuzzified statistical summary of the model results gives indices of sensitivity and uncertainty that relate the effects of variability and uncertainty of input variables to model predictions. The feasibility of the method is validated to analyze total variance in the calculation of incremental lifetime risks due to polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) for the residents living in the surroundings of a municipal solid waste incinerator (MSWI) in Basque Country, Spain. The second part of this thesis deals with the use of artificial intelligence technique for generating environmental indices. The first paper focused on the development of a Hazzard Index (HI) using persistence, bioaccumulation and toxicity properties of a large number of organic and inorganic pollutants. For deriving this index, Self-Organizing Maps (SOM) has been used which provided a hazard ranking for each compound. Subsequently, an Integral Risk Index was developed taking into account the HI and the concentrations of all pollutants in soil samples collected in the target area. Finally, a risk map was elaborated by representing the spatial distribution of the Integral Risk Index with a Geographic Information System (GIS). The second paper is an improvement of the first work. New approach called Neuro-Probabilistic HI was developed by combining SOM and Monte-Carlo analysis. It considers uncertainty associated with contaminants characteristic values. This new index seems to be an adequate tool to be taken into account in risk assessment processes. In both study, the methods have been validated through its implementation in the industrial chemical / petrochemical area of Tarragona. The third part of this thesis deals with decision-making framework for environmental risk management. In this study, an integrated fuzzy relation analysis (IFRA) model is proposed for risk assessment involving multiple criteria. The fuzzy risk-analysis model is proposed to comprehensively evaluate all risks associated with contaminated systems resulting from more than one toxic chemical. The model is an integrated view on uncertainty techniques based on multi-valued mappings, fuzzy relations and fuzzy analytical hierarchical process. Integration of system simulation and risk analysis using fuzzy approach allowed to incorporate system modelling uncertainty and subjective risk criteria. In this study, it has been shown that a broad integration of fuzzy system simulation and fuzzy risk analysis is possible. In conclusion, this study has broadly demonstrated the usefulness of soft computing approaches in environmental risk analysis. The proposed methods could significantly advance practice of risk analysis by effectively addressing critical issues of uncertainty propagation problem. / Los problemas del mundo real, especialmente aquellos que implican sistemas naturales, son complejos y se componen de muchos componentes indeterminados, que muestran en muchos casos una relación no lineal. Los modelos convencionales basados en técnicas analíticas que se utilizan actualmente para conocer y predecir el comportamiento de dichos sistemas pueden ser muy complicados e inflexibles cuando se quiere hacer frente a la imprecisión y la complejidad del sistema en un mundo real. El tratamiento de dichos sistemas, supone el enfrentarse a un elevado nivel de incertidumbre así como considerar la imprecisión. Los modelos clásicos basados en análisis numéricos, lógica de valores exactos o binarios, se caracterizan por su precisión y categorización y son clasificados como una aproximación al hard computing. Por el contrario, el soft computing tal como la lógica de razonamiento probabilístico, las redes neuronales artificiales, etc., tienen la característica de aproximación y disponibilidad. Aunque en la hard computing, la imprecisión y la incertidumbre son propiedades no deseadas, en el soft computing la tolerancia en la imprecisión y la incerteza se aprovechan para alcanzar tratabilidad, bajos costes de computación, una comunicación efectiva y un elevado Machine Intelligence Quotient (MIQ). La tesis propuesta intenta explorar el uso de las diferentes aproximaciones en la informática blanda para manipular la incertidumbre en la gestión del riesgo medioambiental. El trabajo se ha dividido en tres secciones que forman parte de cinco artículos. En la primera parte de esta tesis, se han investigado diferentes métodos de propagación de la incertidumbre. El primer método es el generalizado fuzzy α-cut, el cual está basada en el método de transformación. Para demostrar la utilidad de esta aproximación, se ha utilizado un caso de estudio de análisis de incertidumbre en el transporte de la contaminación en suelo. Esta aproximación muestra una superioridad frente a los métodos convencionales de modelación de la incertidumbre. La segunda metodología propuesta trabaja conjuntamente la variabilidad y la incertidumbre en los modelos de evaluación de riesgo. Para ello, se ha elaborado una nueva aproximación híbrida denominada Fuzzy Latin Hypercube Sampling (FLHS), que combina los conjuntos de la teoría de probabilidad con la teoría de los conjuntos difusos. Una propiedad importante de esta teoría es su capacidad para separarse los aleatoriedad y imprecisión, lo que supone la obtención de una mayor calidad de la información. El resumen estadístico fuzzificado de los resultados del modelo generan índices de sensitividad e incertidumbre que relacionan los efectos de la variabilidad e incertidumbre de los parámetros de modelo con las predicciones de los modelos. La viabilidad del método se llevó a cabo mediante la aplicación de un caso a estudio donde se analizó la varianza total en la cálculo del incremento del riesgo sobre el tiempo de vida de los habitantes que habitan en los alrededores de una incineradora de residuos sólidos urbanos en Tarragona, España, debido a las emisiones de dioxinas y furanos (PCDD/Fs). La segunda parte de la tesis consistió en la utilización de las técnicas de la inteligencia artificial para la generación de índices medioambientales. En el primer artículo se desarrolló un Índice de Peligrosidad a partir de los valores de persistencia, bioacumulación y toxicidad de un elevado número de contaminantes orgánicos e inorgánicos. Para su elaboración, se utilizaron los Mapas de Auto-Organizativos (SOM), que proporcionaron un ranking de peligrosidad para cada compuesto. A continuación, se elaboró un Índice de Riesgo Integral teniendo en cuenta el Índice de peligrosidad y las concentraciones de cada uno de los contaminantes en las muestras de suelo recogidas en la zona de estudio. Finalmente, se elaboró un mapa de la distribución espacial del Índice de Riesgo Integral mediante la representación en un Sistema de Información Geográfico (SIG). El segundo artículo es un mejoramiento del primer trabajo. En este estudio, se creó un método híbrido de los Mapas Auto-organizativos con los métodos probabilísticos, obteniéndose de esta forma un Índice de Riesgo Integrado. Mediante la combinación de SOM y el análisis de Monte-Carlo se desarrolló una nueva aproximación llamada Índice de Peligrosidad Neuro-Probabilística. Este nuevo índice es una herramienta adecuada para ser utilizada en los procesos de análisis. En ambos artículos, la viabilidad de los métodos han sido validados a través de su aplicación en el área de la industria química y petroquímica de Tarragona (Cataluña, España). El tercer apartado de esta tesis está enfocado en la elaboración de una estructura metodológica de un sistema de ayuda en la toma de decisiones para la gestión del riesgo medioambiental. En este estudio, se presenta un modelo integrado de análisis de fuzzy (IFRA) para la evaluación del riesgo cuyo resultado depende de múltiples criterios. El modelo es una visión integrada de las técnicas de incertidumbre basadas en diseños de valoraciones múltiples, relaciones fuzzy y procesos analíticos jerárquicos inciertos. La integración de la simulación del sistema y el análisis del riesgo utilizando aproximaciones inciertas permitieron incorporar la incertidumbre procedente del modelo junto con la incertidumbre procedente de la subjetividad de los criterios. En este estudio, se ha demostrado que es posible crear una amplia integración entre la simulación de un sistema incierto y de un análisis de riesgo incierto. En conclusión, este trabajo demuestra ampliamente la utilidad de aproximación Soft Computing en el análisis de riesgos ambientales. Los métodos propuestos podría avanzar significativamente la práctica de análisis de riesgos de abordar eficazmente el problema de propagación de incertidumbre.
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Beräkning av massbalanser för metaller i vatten samt miljöriskbedömning av Nerån vid Österbyverken i Östhammars kommunLadekrans, Thereze January 2011 (has links)
Österbyverken is an industrial estate in Östhammars municipality in Uppland, Sweden. Many different activities have taken place on the estate the last 600 years. During the last 15 years both health and environmental studies have been made by different companies. At the most recent study a great increase of metals in Nerån, a river that runs partly through and partly next to the estate, was identified with mass balances. The purpose of this thesis is to accomplish a deepened study about the reasons for the increase of metals in Nerån. The aim is to identify knowledge gaps in the mass balances and try to complete these. From the outcome an environmental risk assessment will be attempted for Nerån and its outlet in the lake Filmsjön. The method went through steps and started with data analyses after which calculations for new mass balances were made. Beginning by acknowledge the increase of metals from the groundwater, both through measured results and through calculated confidence intervals. In addition, among other methods, calculations of theoretical leakage data from Kd-values were made. Surface water concentrations were also compared with levels of metals in sediments to see whether any connection existed between them. Additional mass balances were calculated to take suspended solids in the surface water under consideration. From the results an environmental risk assessment was made using guidelines from Netherland and Canada and the state division from the Swedish Environmental Protection Agency. The results of the study show that the differences of metal content between surface water and groundwater and between surface water and sediments might be smaller than first revealed, but there is still a great increase caused by another, unknown source. The environmental risk assessment shows that there are hazards for both Nerån and Filmsjön because of the leakage of metals from Österbyverken. For the surface water in Nerån it is mainly cobalt, copper and zinc that contributes with risks, for the sediment in Nerån it is mainly barium, cobalt, copper, chromium and nickel and for the sediments in Filmsjön it is mainly lead, cobalt, copper, chromium, nickel and zinc. Reasons for the differences between metal contents and medias might be from surface water outlet from the Österbyverken or because of differences in methods of taking specimens in surface and groundwater. Conclusions that have been drawn of the study is that further studies of the knowledge gaps needs to be done, particularly regarding the metals cobalt, copper, chromium, nickel and zinc. Further, the biodiversity in Nerån and Filmsjön is at risk, partly because several metals in the sediments reaches such high concentrations, partly because high concentrations of several metals in one area may increase risks.
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Personality and motivation in an augmented PRISM : risk information seeking in the context of the indoor environmentRosenthal, Sonny Ben 21 June 2011 (has links)
This dissertation augmented Kahlor’s (2010) planned risk information seeking model (PRISM). According to the PRISM, people’s intentions to seek risk information hinge on their attitudes toward seeking, seeking-related subjective norms, perceived control over seeking, affective response to the perceived risk, and information need. As well, this dissertation examined the role of self-identity as an information seeker, independent self-construal, past risk information seeking, involvement, and motivation orientation in people’s intention to seek risk information about radon and poor indoor air quality. In a pilot study of a convenience sample (N = 59), I derived an information-seeking self-identity scale and a novel instrument for measuring information need. The main study of a national probability sample (N = 602) evaluated the proposed structural model, tested several hypotheses, and explored several research questions. Both the pilot and main study gathered data via online surveys. Results supported the proposed model (R2 = .62) and several hypotheses. Notably, information-seeking self-identity and past risk information seeking positively predicted seeking intention. Also, the effects of attitudes and norms on seeking intention were stronger among more independent respondents. Finally, in a series of multiple regression analyses, I detailed the roles of involvement and various motivation orientations in each model component. An unexpected finding was that perceived control over seeking did not significantly predict seeking intention. Post-hoc analysis revealed that the strength of the control-intention relationship was—at least with the current sample—inversely related to socioeconomic status (SES), where at higher levels of SES, the importance of perceived control over seeking diminished. / text
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Perceptions of risk to water environments in the lower Fraser basin, British ColumbiaCavanagh, Nigel Steven 05 1900 (has links)
The following thesis presents the results of a two year study that addressed lay
perceptions of the risks to the water resources of the Lower Fraser Basin, British
Columbia. Studies of this nature are important because by clarifying public perceptions,
risk communication policies as well as land and water resource use plans that accommodate
people's concerns can be developed appropriately. The study was based on a written
survey that was administered to 183 lay subjects in four communities within the Lower
Fraser Basin. Sixteen experts participated in a portion of the survey. Analysis involved the
determination of how people perceive distinct human activities in terms of the risk each may
pose to the health of aquatic ecosystems. Further analysis compared these perceptions to
those of specialists in the aquatic sciences. The thesis is structured as a collection of three
papers that examine different aspects of the study. The First paper provides a review of the
overall data set, while the remaining two papers address related subsets of the data. One
paper reviews perceptions of activities that cause eutrophication problems and the other
reviews perceptions of forest industry activities. The results demonstrated that people tend
to view risks to water environments in a multi-faceted fashion. Four factors were found to
influence people's general perception of risk and the need for regulation of the activities that
were perceived to pose the risk. These factors were termed Ecological Impact, Human
Benefit, Controllability and Knowledge. Another significant result was the fact that there
were often striking differences between the views of the lay sample and those of the expert
sample. Some activities were perceived by the lay sample as posing substantial risk while
the experts did not view this to be the case. Alternatively, for some activities, the reverse
scenario occurred. Accordingly, there were differences in judgements between the two
groups as to the degree of regulation that should be imposed on the respective activities.
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Activity-based life-cycle assessments in design and managementEmblemsvåg, Jan 08 1900 (has links)
No description available.
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Development and application of a generalized physiologically-based toxicokinetic model for environmental risk assessmentSasso, Alan F., January 2010 (has links)
Thesis (Ph. D.)--Rutgers University, 2010. / "Graduate Program in Chemical and Biochemical Engineering." Includes bibliographical references (p. 209-237).
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A SPATIAL ANALYSIS OF INVASIVE BREAST CANCER CLUSTERS IN ASSOCIATION WITH ENVIRONMENTAL RISK FACTORS: ILLINOIS 1996 TO 2000Weston, William Christopher 01 August 2012 (has links)
This retrospective study assesses invasive breast cancer counts reported at the Illinois ZIP code scale during the study period of 1996 to 2000. The research objective is to evaluate the spatial and statistical associations between breast cancer risk and sources of potential environmental contamination. A thorough literature review illustrates a profound list of cancer risk factors within the study space. Public health principles are utilized to prepare breast cancer incidence for analysis, accompanied with the development of a case/control ecological model. Exploratory analyses suggest that breast cancer intensity is predominantly a rural problem. A generalized linear mixed model is employed, illustrating statistical associations between environmental risk factors and breast cancer risk. Coal Mines, Oil/Gas Wells, and Large Quantity Hazardous Waste Generators, display high statistical significance (p<0.001) in association with increased breast cancer risk. Unique socioeconomic attributes distinguish urban risk from rural risk, as can be seen in a discriminant function analysis. The modeling techniques utilized in this research display classic spatial epidemiological approaches that account for particular types of confounding effects, while also defining zones of disease risk through cluster detection. Results from this analysis are useful for future studies intended to account for epidemiological, clinical, chemical and biological disease-related information.
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Avaliação da sensibilidade ambiental costeira e análise de risco socioambiental do litoral centronorte catarinense, com base na vulnerabilidade do ambiente às mudanças climáticas.Scolaro, Thelma Luiza January 2013 (has links)
O objetivo deste trabalho é contribuir para a compreensão da sensibilidade ambiental e risco socioambiental do setor costeiro centro-norte do Estado de Santa Catarina (de Biguaçu a Itapoá). Para atingir o objetivo proposto foi aplicada uma metodologia, adaptada do método Smartline proposto para a costa Australiana, denominada ISAC – Índice de Sensibilidade Ambiental Costeira, que se apresenta neste estudo dividida da seguinte forma: (a) análise das variáveis regionais de vulnerabilidade costeira da região centro-norte Catarinense; (b) avaliação de critérios como geologia, geomorfologia, clima, dinâmica marinha, topografia e socioeconomia da área de estudo; (c) classificação hierárquica frente a fatores de resistência e/ou função ecológica e posterior ponderação de acordo com a sensibilidade de cada critério a eventos extremos e a elevação do nível médio dos oceanos; (d) elaboração de mapas temáticos contendo informações da sensibilidade ambiental presente nas praias do litoral centro e norte de Santa Catarina para cenários de ondulação provenientes de Leste e Sudeste. O ISAC demonstrou que 39% da zona costeira, apresenta sensibilidade Alta para o cenário de ondulação proveniente de Leste, seguido pelos valores de 18% que apresenta sensibilidade Baixa, 17% com sensibilidade Muito Alta e 16% com sensibilidade Muito Baixa. Para o cenário de ondas provenientes de Sudeste, 41% da área de estudo apresenta Alta sensibilidade em seus segmentos costeiros, com valores menores na sequência, onde 20%, 15% e 13% da costa demonstraram sensibilidade Baixa, Muito Baixa e Muito Alta respectivamente. Com relação ao risco socioambiental costeiro, no cenário com ondulações de Leste, 51% da linha de costa apresenta risco Médio, 30% risco Alto e 18% risco Baixo e referente ao cenário de Sudeste 53%, 27% e 20% do segmento costeiro apresentam risco Médio, Alto e Baixo respectivamente. O ISAC e a Análise de Risco Socioambiental mostraram-se eficientes para uma avaliação regional do litoral centro-norte de Santa Catarina. Entretanto, salienta-se que para a realização de uma análise local, de maior detalhe, se faz necessário a obtenção de um volume maior de informações, a cerca dos critérios ou parâmetros ambientais, através de campanhas de campo. / The aim of this study is to contribute to the understanding of environmental sensitivity and Social Environmental risk for the central-north coastal sector of the Santa Catarina State (from Biguaçu to Itapoá). To achieve the proposed objective the ISAC - Coastal Environmental Sensitivity Index methodology was applied, adapted from the Smartline method proposed for the Australian coast. In this study the ISAC methodology is divided as follows: (a) regional variables analysis of coastal vulnerability for the central-north region of Santa Catarina; (b) assessment of the criteria such as geology, geomorphology, climate, marine dynamic, topography and social-economy of the study area; (c) hierarchical classification against resistance factors and/or ecological function and subsequent pondering according to the sensitivity of each criterion to extreme events and mean sea level rise; (d) development of thematic maps containing the environmental sensitivity information of the study area for two different wave scenarios, waves from the East and Southeast directions. The ISAC showed that 39% of the coastal area has High sensitivity for the East waves, followed by the values of 18% which has Low sensitivity, 17% with Very High and 16% with Very Low sensitivity. For the Southeast waves scenario, 41% of the study area has High sensitivity in the coastal sections, with lower values in the sequence, where 20%, 15% and 13% of the coast showed the sensitivity as Low, Very Low and Very High respectively. Regarding the social environmental coastal risk, for the East wave scenario, 51% of the coastline presents Medium risk, 30% High risk and 18% Low risk. For the Southeast waves scenario, 53%, 27% and 20% of the coastal segment has Medium, High and Low risk respectively. The ISAC and the Social Environmental Risk analysis were effective for a regional assessment of the central northern coast of Santa Catarina. However, it is noted that to perform a detailed local analysis is necessary to obtain a greater volume of information about the criteria or environmental parameters through field campaigns.
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Toxicidade aguda e risco ambiental do diflubenzuron para Daphnia magna, Poecilia reticulata e Lemna minor na ausência e presença de sedimentoSouza, Jaqueline Pérola [UNESP] 07 March 2008 (has links) (PDF)
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souza_jp_me_jabo.pdf: 1313453 bytes, checksum: 4c61c83068fdecf5e8c6a9ee5b5f525e (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O inseticida diflubenzuron (DFB), comercializado como Dimilin®, é empregado em pisciculturas no tratamento de ecotoparasitoses em peixes. Este composto inibe a síntese de quitina, componente do exoesqueleto dos parasitas. A utilização deste inseticida se deve à sua baixa toxicidade aos peixes e eficácia no controle dos ectoparasitas. Porém, no ambiente aquático o DFB pode ser tóxico à espécies sensíveis e não-alvos, a concentração empregada no tratamento das ectoparasitoses é de 2 mg.L-1. Os objetivos deste estudo foram avaliar a toxicidade do DFB para as espécies de Daphnia magna, Poecilia reticulata e Lemna minor, classificar o produto quanto à sua toxicidade e risco ambiental e avaliar o efeito do sedimento na biodisponibilidade do DFB na água. Os organismos-teste foram submetidos a concentrações crescentes do inseticida em salas climatizadas do Laboratório de Ecotoxicologia da FCAV-UNESP. Os testes com D. magna foram realizados em volume de 10 mL a 20° C e cinco organismos neonatos por concentração, durante 48 horas na presença e ausência de sedimento. Os peixes (P. reticulata) foram expostos às concentrações do DFB por 96 horas em testes na presença e ausência de sedimento. O volume final foi de 3000 mL e cinco animais por concentração à 25° C. As plantas de L. minor foram expostas ao DFB por sete dias na presença e ausência de sedimento. O volume final foi de 100 mL e 12 frondes por concentração à 24° C. Os testes foram realizados com três réplicas incluindo o controle. As CE50-48h calculadas para D. magna foram de 0,56 μg.L-1 e 1,51 μg.L-1 na ausência e presença de sedimento respectivamente; as CL50-96h para P. reticulata foram 152,00 mg.L-1 e 277,83 mg.L-1 na ausência e presença de sedimento respectivamente; e as CE50-7dias para L. minor foram 459,50 mg.L-1 e 698,25 mg.L-1 na ausência e presença de sedimento respectivamente... / The insecticide diflubenzuron (DFB), marketed as Dimilin®, is used in fish farms to treat ectoparasites in fishes. This compound inhibits the chitin synthesis, exoskeleton component of the parasites. The use of this insecticide is due to its low toxicity for fish and effectiveness in the control of ectoparasites. However, the DFB in the aquatic environmental can be toxic to sensitive species and non-targed, the concentration used in the treatment of ectoparasites is 2 mg.L-1. The aims of this study were to evaluate the toxicity of the DFB for the species of Daphnia magna, Poecilia reticulata and Lemna minor, classify the product as to their toxicity and environmental risk and evaluate the effect of sediment on the bioavailability of the DFB in the water. The organisms-test were submitted to increasing concentrations of insecticide in air conditioned rooms of the Laboratory of Ecotoxicology FCAV-UNESP. Tests with D. magna were performed in volume of 10 mL at 20° C and five organisms neonates (6 and 24 hours of age) in each concentration, for 48 hours in the presence and absence of sediment. Fishes (P. reticulata) were exposed to concentrations of the DFB for 96 hours in tests in the presence and absence of sediment. The final volume was 3000 mL and five animals per concentration to 25° C. The plants of L. minor were exposed to the DFB for seven days in the presence and absence of sediment. The final volume was 100 mL and 12 fronds by concentration to 24° C. The tests were performed with three repetitions incluing the control. The EC50-48h estimeds for D. magna were 0.56 and 1.51 μg.L-1 in the absence and presence of sediment respectively; the LC50-96h for P. reticulata were 152.00 mg.L-1 and 277.83 mg.L-1 in the absence and presence of sediment respectively; and the EC50-7dias to L. minor were 459.50 mg.L-1 and 698.25 mg.L-1 in the absence and presence of sediment respectively...(Complete abstract, click electronic access below)
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