Worldwide, estuaries are under increasing pressure from numerous contaminants. There is a need to develop reliable bioassay methodologies to assess the effects of these stressors on estuary health. This thesis aimed to develop and validate toxicity tests in a New Zealand marine harpacticoid copepod species for use in monitoring and evaluating the effects of estuarine pollution. A survey and toxicological assessment of a range of native copepod species resulted in the selection of Quinquelaophonte sp. as the ideal bioassay species. This selection was based on a broad regional distribution, ease of culture and high reproductive rate in the laboratory, sexual dimorphism, and sensitivity to contaminants. To validate the bioassay, spiked sediments were used to expose Quinquelaophonte sp. to three reference compounds representing important categories of estuarine chemical stressors: zinc (a metal), atrazine (a pesticide), and phenanthrene (a polyaromatic hydrocarbon). A method for spiking sediments that Quinquelaophonte sp. inhabit was developed to ensure even contaminant distribution in sediments. Two sediment bioassays using lethal and sublethal endpoints were validated, one acute (96 h) and one chronic (14 d). These assays incorporated both lethal and sublethal endpoints, which included reproductive output and mobility. Acute-to-chronic ratios were calculated for use in environmental risk assessment and to provide insight into the mode of action of the reference contaminants. The chronic sediment bioassay was used to assess sediment quality in three estuaries across New Zealand: Napier, Christchurch and Invercargill. This validated the bioassay for use with naturally-contaminated field sediments with varying mixtures of pollutants and sediment types (coarse sandy to fine silty organic rich sediments). Quinquelaophonte sp. was also tested to assess whether it can be used to characterise multi–generation impacts. After four generations of exposure to zinc, there were changes in acute sensitivity, indicating this species possesses mechanisms for acclimating or adapting to toxic stressors. Sediment bioassays in Quinquelaophonte sp. were successfully developed and validated, offering significant promise as a tool for monitoring effects of pollution in New Zealand estuaries.

British Columbia salmon aquaculture operations use the chemotherapeutant emamectin benzoate (EMB trade name SLICE®), a synthesized avermectin compound, delivered through feed to decrease sea lice (Lepeophtheirus salmonis) parasite abundance on production fish. Avermectins bind to ion channels in crustaceans and disrupts nerve impulse transmission. Detectable amounts of EMB can accumulate in the depositional area around farms during SLICE® treatment periods, thus presenting potential for exposure to populations of proximate non-target species. The distribution of spot prawn (Pandalus platyceros), an economically important crustacean, overlaps with areas of intensive salmon farm activity. The primary objective of this research was to determine if EMB exposure had a measurable biological effect on spot prawns in the field and in the laboratory. The field component was conducted in the Broughton Archipelago, BC, to determine if emamectin benzoate residues could be detected near actively treating salmon farms, and whether farm proximity affected spot prawn size distribution. Three laboratory experiments tested the mortality, molting and behavioural response of spot prawns to SLICE® feed pellet exposure and acute exposure to EMB through sediment over ten, 30 and 45-day durations. Measurable amounts of EMB was detected in the marine sediment near five farm sites during the field survey and was found to persist between treatment periods. Male and transitional stage spot prawns captured near farm sites attained a greater size and had better body condition compared to reference sites, indicating prawns may benefit from direct or indirect farm food subsidies. However, at several farm sites the size distribution of prawns changed over the sampling period, a trend not observed at reference sites, demonstrating that farm activity may alter prawn population dynamics. Laboratory results indicated that only prawns that had been starved prior to exposure would initially consume SLICE® pellets, but feeding rates declined with subsequent exposures. Depressed consumption rates was not a residual effect of EMB, but rather an aversion to the SLICE® pellet diet as prawns resumed feeding when offered a preferred diet. Sediment EMB exposures to doses 808 µg kg-1 and greater increased prawn mortality, largely due to the inability of molting individuals to successfully complete ecdysis. Exposed individuals accumulated EMB in their abdomen tissue with levels increasing with exposure dose. Prawns exposed to EMB through sediment at concentrations 1419 and 3330 µg kg-1 displayed a significant reduction in olfactory detection and orientation behaviours to food stimuli. This research highlights that spot prawns may avoid SLICE® pellets for preferential food sources, and that only short term EMB exposure 50 to 200 magnitude greater than levels present in the marine environment elicited a measurable response in spot prawn mortality rates, molting success and behaviour. However, preliminary trends in the field survey data indicate that there may be population differences occurring in spot prawns inhabiting areas near treating salmon farms that are not observed in reference populations. These results signify the inherent pitfalls in current management policy that base decisions on short-term acute toxicity laboratory exposure results that may not be indicative of the response of marine populations near active salmon farms to long-term chronic EMB exposure. / Graduate / 0792 / 0329 / 0768

Made available in DSpace on 2014-06-11T19:30:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-07-18Bitstream added on 2014-06-13T19:00:42Z : No. of bitstreams: 1 winkaler_eu_dr_jabo.pdf: 2401389 bytes, checksum: 3b8d20a39c2ee3641205a9c6930923aa (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Dentre os agrotóxicos comumente utilizados na piscicultura para controle de ectoparasitos e insetos aquáticos, destacam-se o diflubenzuron (Dimilin®) e o teflubenzuron (Nomolt®), inseticidas com ação reguladora do crescimento. Na aqüicultura, o tratamento com inseticidas pode ser realizado com a aplicação direta na água, ou administração na ração dos animais. Apesar de muito utilizados, poucos são os trabalhos sobre ecotoxicologia, comportamento e bioacumulação do diflubenzuron (DFB) e teflubenzuron (TFB) na água e seus efeitos em organismos aquáticos de clima tropical. Os objetivos deste trabalho foram: estimar a toxicidade (CL(50-96h)) do DFB e TFB para o pacu (Piaractus mesopotamicus), calcular o risco alimentar para o consumo humano, determinar resíduos de DFB e TFB na água, sedimento e músculo de pacus, após a exposição aos inseticidas na água ou na ração dos peixes e analisar a atividade hepática das enzimas glutationa-S-transefrase (GST) e catalase (CAT) em pacus alimentados com ração acrescida de DFB ou TFB. A CL50;96h do DFB para o pacu foi superior a 1200 mg.L-1 e a do TFB, superior a 1000 mg.L-1. Os resíduos de DFB foram detectáveis até 7 dias após a aplicação (com 18,3% de resíduo) e para o TFB, foram detectáveis ate o terceiro dia (8% de resíduo). No sedimento, as maiores concentrações de DFB e TFB foram observadas nas primeiras 24 h e em todos os períodos amostrados foram detectados resíduos dos inseticidas. Nos filés dos pacus foram detectados resíduos dos inseticidas após a alimentação com a ração tratada e após aplicação de DFB e TFB na água. A ingestão diária estimada (IDE) de DFB e TFB encontra-se acima dos valores de ingestão diária aceitável (IDA), mesmo para as amostras com menores valores de resíduos detectados nos filés do pacu. Em relação aos biomarcadores bioquímicos... / Diflubenzuron and teflubenzuron are growth regulator inhibitors insecticides, used to control ectoparasites in fish and aquatic insects. In aquaculture these pesticides can be injected directly in the water or in the fish food. Besides their large utilization, there are few works about the effects of these insecticides on the fish metabolism and biomagfication, especially in tropical aquatic organisms. This study aims to: evaluate the acute toxicities (LC(50-96h)) in pacu (Piaractus mesopotamicus), measure the risk food for human consumption, determinate residues of DFB and TFB in water, sediment and muscle of pacus after the management of the insect-powders on water or in the fish food and to analyze the hepatical activity of the enzymes catalase (CAT) and glutathione-S-transferase (GST) in fishes fed with ration plus DFB or TFB. The LC((50- 96h)) of DFB and TFB for the pacu was higher than 1.200 mg.L-1 and 1.000 mg.L-1, respectively. The residues TFB were detected until the thirth day (8% of residue) and DFB until seventh day after application in the water (18,3% of residue). In the sediment, the highest concentrations of DFB and TFB had been observed in the first 24 h and in all the samplings there were . In muscle of pacus, residues of the insecticides had been detected after the feeding with the ration treated and after application to DFB and TFB in the water. The daily ingestion estimate (DIE) of DFB and TFB meets above of the values of acceptable daily ingestion (DAI), exactly for the samples with lesser values of residues detected in filés of pacu. For the enzymes the CAT activity was not affected by both pesticides, but the GST activity was reduced five days after the feeding. Besides the importance of the evaluation of the toxicity of DFB and TFB for the fish, the determination of residues and the alimentary risk, it can subsidize the determination of measures of sanitary... (Complete abstract click electronic access below)

Neonicotinoid exposure has been recognised as potentially impacting upon bee health, but whether realistic exposure scenarios are driving declines in bee health is not known. This thesis contributes new insights and perspectives to this research field investigating the use of molecular, physiological and behavioural endpoints as potential ecotoxicological markers for pesticide risk assessment. The thesis presents experimental data for dietary exposures of the European honey bee, Apis mellifera, and the buff-tailed bumble bee, Bombus terrestris, to one of two neonicotinoid pesticides, imidacloprid and thiamethoxam. The first part of this thesis explores impacts of chronic dietary exposures to neonicotinoid pesticides on bee immunocompetence- the ability to mount an immune response- using an artificial challenge to invoke an immune response in adult workers. Levels of phenoloxidase, an enzyme involved in melanisation and part of the bee’s defence system, were largely constitutive and resilient to exposure in honey bees and bumble bees. In honey bees, transient transcriptional changes in antimicrobial effector genes were observed following neonicotinoid exposure, but the physiological antimicrobial response was unaffected. In bumble bees, the induced antimicrobial response was impaired following neonicotinoid exposure, but only when exposed to concentrations likely higher than realistic environmental exposure scenarios. The next phase of this thesis investigates whether transcriptional, physiological and behavioural endpoints associated with the functioning of the honey bee hypopharyngeal gland were altered by imidacloprid exposure. Imidacloprid exposure led to transcriptional changes in foraging genes (associated with the control of temporal polyethism) and major royal jelly proteins (fed to developing larvae by nurse workers) and enzymatic changes in glucose oxidase (an enzyme involved in social immunity), which I hypothesise are linked with hypopharyngeal gland development. Despite these laboratory observations, no behavioural effects were observed in a field setting, monitored using Radio Frequency Identification transponders. Lastly, using RNA-Sequencing to investigate changes across the honey bee transcriptome, this thesis identified a suite of genes that were differentially expressed in adult workers in response to immune challenge and/or dietary neonicotinoid exposure. Wounding and bacterial-like infection led to upregulation of known immune genes, including a peptidoglycan recognition protein and antimicrobial effectors. Chronic exposure to thiamethoxam and imidacloprid led to downregulation of genes associated with several metabolic pathways, such as oxidative phosphorylation, pyruvate- and purine- metabolic pathways, as well as ribosomal activity. Some of these genes identified provide candidates for further study to elucidate functional effects mechanisms and better understand health outcomes, as well as potential new biomarkers for use in pesticide risk assessment. This thesis presents novel findings and offers opportunities for future research that will be of interest to a wide audience, including risk assessors and policy makers, as well as the broader biological community, including ecotoxicologists, insect physiologists and molecular biologists.

A number of pharmaceuticals have been shown to have adverse effects on key biological processes of aquatic organisms at low concentrations (ng/l range). Key questions for chemical risk assessment are whether such pharmaceuticals can produce adverse effects on organisms when present in the environment in combination and at low concentrations, whether these can be classified as additive, and under what circumstances can they be predicted. The main purpose of this study was to assess the potential for combination effects of a multicomponent steroid pharmaceutical mixture of dissimilarly acting compounds on an ecologically relevant end point – reproduction, using the existing predictive toxicity models Concentration Addition (CA) and Independent Action (IA). Concentrations of steroids close to those reported in the environment were shown to produce adverse effects on reproduction when present in combination with other steroids. Clear combination effects significantly larger than the effects of the individual compounds were observed when each compound was present at a concentration below the detection limit of the assay, demonstrating a ‘something from nothing’ mixture effect. Furthermore, IA predicted more pronounced effects on egg production that CA, an observation previously unreported from the literature. Actual observed effects were closer to the IA prediction. Additional biomarker and molecular endpoints were examined in subsequent studies to establish the mechanisms of disrupted reproduction in pair-breeding FHMs exposed to the steroid mixture. Results from this study indicate that reproductive impairment of fish exposed to the steroid mixture is likely due to the masculinisation of female fish due to the androgenic activity of the mixture. These results have implications for chemical risk assessment, and in particular, highlight the need for caution when using CA as a worst-case approximation of mixture effects.

North American scoter populations have declined by approximately 60% over the last 30-50 years. Prior studies of other sea duck species suggest that trace elements can have deleterious effects on overall body condition. For surf scoters (Melanitta perspicillatta) and white-winged scoters (Melanitta fusca), this study tested the following hypotheses: (1) Trace element accumulation differs among seasons, locations, and species; (2) Increased trace elements in tissues correlate with declines in body condition; (3) Surf scoters that shift their feeding to a higher trophic level in spring bioaccumulate higher levels of trace elements; and (4) Selenium and mercury co-accumulate in a 1:1 molar ratio. To test these hypotheses, cadmium (Cd), mercury (Hg), and selenium (Se) in livers and kidneys were collected from adult male surf scoters and white-winged scoters in December 2005 and March 2006 from three locations in Puget Sound, Washington. Trace elements in surf scoters differed among locations, and seasons. Se and Cd in liver and kidney explained 21% of the variance in a matrix of body condition factors in surf scoters. In white-winged scoters, body condition differed between March and December, but trace elements in tissues did not, indicating that contaminants did not explain changes in condition. Thus, hypotheses 1 and 2 received partial support while hypothesis 3 did not. Finally, Se and Hg did not covary in either the kidney or liver of either species (hypothesis 4). Compared to other marine birds, scoters in this study contained low contaminant levels. Nonetheless, inorganic contaminants explained substantial variation in body condition of surf scoters, and potentially contribute to their population declines. These findings suggest that inorganic contaminants, particularly Cd, should be considered in assessing habitat quality for sea ducks.

Fundação de Amparo a Pesquisa no Estado do Rio Grande do Sul / Essential to life, water is present in almost all human activities, mainly in the consumption of drinking water and agricultural activities. Considering that the world population has increased enormously, food production must be increased and this need has encouraged cooperatives and producers to seek alternative techniques to improve productivity and reduce costs. In this context, the addition of hydrogels on the ground, optimizes the availability of water due to its large storage capacity, accelerating the development of the root system and aerial part of the plant. Most hydrogels is done based on polyacrylamide polymer of acrylamide (AM) monomer which is in the form odorless and white colored water soluble and highly toxic. The damaging effects of AM, which has carcinogenic risk and endocrine disrupter in living beings are known for over 30 years. In soil, acrylamide has a high time to be degraded and due to leaching, the monomer can be found in aquatic environments. Due to its toxicity, acrylamide in a concentration of 5.88 mg / L-1 restates the EC50 microalgae Chlorophyceae Desmodesmus quadricauda (Turpin) Brébisson. In addition to the influence of pollution, various abiotic factors such as temperature and pH, interfere with aquatic communities. The aim of this study was to evaluate the toxic effects of acrylamide in predetermined concentration with changes in temperature (24 ° C and 17 ° C) and pH variation on physiological parameters of microalgae D. quadricauda. The green algae were grown in Water Culture (WC) with its exposed cells in exponential growth phase for a period of 72 hours at concentrations of 5.88 mg l-1 of acrylamide, pH values ranging from 5, 6, 7 and 8. Periodic samples counts were performed under the microscope, in which it took into account the phenotypic plasticity and cellular measures, the biovolume and cell density. When comparing this study with acrylamide EC50 obtained in a previous study, the results indicated at low temperatures (17 ° C) the toxicity of acrylamide and decreased at high temperatures (24 ° C) increased, not having the pH interfered in this parameter. Analyzing cellular measures of width and length, results were significant with the control of pH 8 and temperature 15 ° C, as in biovolume values where only the variation of pH shows variation among the tested controls and treatments. Phenotypic gender plasticity shows that when analyzing the groups separately for periods of 24, 48 and 72 hours, although no significant differences, most phenotypic change was found in the monasteries of a cell that prevailed most in the group treated with acrylamide and pH change in almost all periods. Therefore, the concentration of acrylamide in this test along with changes in temperature and pH tested, indicating that the toxicity of the substance changes the parameters tested in microalgae, becoming a risk to aquatic communities exposed to acrylamide. / Essencial à vida, a água está presente em quase todas as atividades humanas, principalmente no consumo de água potável e em atividades agrícolas. Tendo em vista que a população mundial vem aumentando enormemente, a produção de alimentos tem de ser aumentada sendo que esta necessidade tem-se estimulado cooperativas e produtores a buscarem técnicas alternativas para a melhoria da produtividade e redução de custos. Neste contexto, a adição de hidrogéis no solo, otimiza a disponibilidade de água , devido à sua grande capacidade de armazenamento, acelerando o desenvolvimento do sistema radicular e da parte aérea das plantas. A maioria dos hidrogeis é feito à base de poliacrilamida, polímero da acrilamida (AM), monômero que se apresenta na forma inodora e de coloração branca, solúvel em água e altamente tóxica. Os efeitos prejudiciais da AM, que apresenta risco carcinogênico e desregulador endócrino nos seres vivos, são conhecidos há mais de 30 anos. No solo, a acrilamida apresenta um elevado período para ser degradada e devido a lixiviação, o monômero pode ser encontrada em ambientes aquáticos. Devido a sua toxicidade, a acrilamida em concentração de 5,88 mg/L-1 reapresenta a EC50 de microalgas clorofíceas Desmodesmus quadricauda (Turpin) Brébisson. Além da influencia da poluição, vários fatores abióticos como temperatura e pH, interferem nas comunidades aquáticas. O objetivo deste estudo foi avaliar os efeitos tóxicos da acrilamida em concentração pré-estabelecida juntamente com alterações de temperatura (24 ºC e 17 ºC) e variação de pH sobre parâmetros fisiológicos da microalga D. quadricauda . As clorofíceas foram cultivadas em meio Water Culture (WC), com suas células em fase exponencial exposta por um período de 72 horas a concentração de 5,88 mg.L-1 de acrilamida, valores de pH que variaram de 5, 6, 7 e 8. Amostras periódicas foram realizadas contagens ao microscópio, em que se levou em consideração a plasticidade fenotípica e medidas celulares, o biovolume e densidade celular. Ao comparar este estudo com a EC50 da acrilamida obtido em estudo prévio, os resultados indicaram que a 17 ºC a toxicidade da acrilamida diminuiu e em temperaturas a 24 ºC aumentou, não tendo o pH interferido neste parâmetro. Analisando as medidas celulares de largura e comprimento, resultados foram significativos com o controle de pH8 e com temperatura a 15ºC, assim como nos valores do biovolume, onde a variação apenas do pH apresenta variação entre os controles e tratamentos testados. A plasticidade fenotípica do gênero aponta que ao analisar os grupos separadamente nos períodos de 24, 48 e 72 horas, que apesar de não haver diferenças significativas, maior alteração fenotípica foi encontrada nos cenóbios de uma célula, que prevaleceu maior no grupo tratado com acrilamida e alteração de pH em praticamente todos os períodos. Portanto, a concentração de acrilamida presente nos ensaios juntamente com alterações de temperatura e pH testadas, indica que a toxicidade da substância altera os parâmetros testados na microalga, se tornando um risco às comunidades aquáticas se expostas a acrilamida.

Engineered nanomaterials (ENMs) have been increasingly used in various applications. Often, the ENMs are functionalised with a surface coating to enhance their properties. Decades of research has provided information on mostly pristine and unmodified ENMs, while ecotoxicity of coated ENMs and how their hazard changes with age in soils is still uncertain. The thesis aimed to determine the toxic effects and bioaccumulation potential of CuO ENMs and CdTe quantum dots (QDs) with different chemical coatings (carboxylate, COOH; polyethylene glycol, PEG; ammonium, NH4+) on the earthworm (Eisenia fetida), and compare the effects to their metal salt (CuSO4) or micron-sized counterpart. Then, to determine if any observed toxicity was altered after ageing the soils for up to one year. Incidental plant growth was studied in the exposure soils to maximise the scientific value of the earthworm tests. Toxic effects of CuO ENMs were also assessed in Caenorhabditis elegans exposed in liquid and soil media to understand effects of the media and method of dosing on ENM toxicity. CuO ENMs were equally toxic to earthworms, or less toxic to plants than the dissolved Cu; whereas CdTe QD ENMs were more toxic than the micron-sized CdTe QDs. There was a coating effect in both, CuO and CdTe QD ENM experiments, the -COOH coated ENMs were most toxic in the fresh soil study, while -NH4+ coated ENMs were most toxic in the aged soil study. Despite the similarities in the toxicity ranking, the biological effects exerted were different between CuO and CdTe QD ENMs. In C. elegans exposures, the ENMs were more hazardous than dissolved Cu, but ranking of ENMs depended on the media and method of dosing. The results suggest the coating effect is determined by the reactivity of the coating in a given media, and it also depends on the core of the ENMs. As such, coating and ageing effects should be considered in the risk assessment of ENMs.

Made available in DSpace on 2014-06-11T19:22:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-03-29Bitstream added on 2014-06-13T19:47:06Z : No. of bitstreams: 1 carraschi_sp_me_jabo.pdf: 1614331 bytes, checksum: 288620069238ff5c63f403a56576fa26 (MD5) / Um dos problemas da aqüicultura é a ocorrência freqüente de infecções por parasitos e bactérias, principalmente em sistemas de criação intensiva. Entre os antibióticos, a oxitetraciclina (OTC) e o florfenicol (FFC) são os mais usados para tratar infecções causadas por bactérias em peixes. Os objetivos foram estimar a concentração letal 50% (CL50;48h) da OTC (Terramicina®) e do FFC (Aquaflor®) para o pacu (Piaractus mesopotamicus), classificar a OTC e o FFC pelo risco de intoxicação ambiental; determinar a dose eficaz de OTC e de FFC administrada na ração para o controle da infecção por Aeromonas hydrophila em pacu; avaliar o efeito da diluição da OTC e do FFC nas variáveis de qualidade de água durante os testes de toxicidade e durante o tratamento e avaliar as alterações histopatológicas após o tratamento com OTC e FFC. Para os testes de toxicidade aguda os animais (peso entre 0,5 e 1,0 g) foram expostos a 7,0; 7,5; 8,0 e 8,5 mgL-1 de OTC ou a 600,0; 700,0; 800,0; 900,0 e 1000,0 mgL-1 de FFC e um tratamento controle. A OTC e o FFC foram classificados pela toxicidade aguda e pelo risco ambiental de acordo com as classes de valores de CL50;48h. Para o tratamento de infecção induzida por A. hydrophila (3.0 x108 bactéria.mL-1), foram realizados dois testes, um com OTC (110,0; 140,0 e 170,0 mg.Kg-1) e outro com FFC (5,0; 10,0 e 15,0 mg.Kg-1). Os tratamentos foram três concentrações de cada antibiótico, um controle sem infecção e um com infecção. Para análise histopatológica foram coletados fragmentos de brânquia, fígado, rim e pele dos peixes após o tratamento com os antibióticos. As variáveis de qualidade de água registradas diariamente foram pH, temperatura, condutividade elétrica e concentração de oxigênio dissolvido, nos testes de toxicidade aguda e durante os testes de concentrações curativas. Nos testes de toxicidade aguda, a CL50;48h... / One of the main problems of modern aquaculture is the occurrence of infection of farmed fish by parasites and bacteria, especially in intensive systems. Among the antibiotics, the oxytetracycline (OTC) and the florfenicol (FFC) are the most commonly used to treat infections caused by bacteria in fishes. The objective was to estimate the 50% lethal concentration (LC50, 48h) of OTC (Terramycin®) and of the FFC (AQUAFLOR®) for the pacu (P. mesopotamicus), classify the OTC and FFC of according the assessment risk and to determine the effective concentration of OTC and of FFC administered in feed for control of Aeromona hydrophila in pacu; to evaluate the effect of dilution of OTC and of the FFC in variables in water quality during toxicity tests and for treatment and to evaluate the histopathological changes after treatment with OTC and FFC. For acute toxicity tests the animals (weighing between 0.5 and 1.0 g) were exposed to 7.0, 7.5, 8.0 and 8.5 mg.L-1 OTC or 600.0, 700 , 0, 800.0, 900.0 and 1000.0 mg.L-1 of FFC and a control treatment. The OTC and the FFC were classified for acute toxicity and for environmental risk of according with the ranking of value of LC 50;48h. For the treatment of A. hydrophila induced by experimental infection (3.0 x108 bactéria.mL-1), were carried out two tests, one with OTC (110.0, 140.0 and 170.0 mg.Kg-1) and another with FFC (5.0; 10.0 and 15.0 mg.Kg-1). The treatments included three concentration of antibiotic, a control without infection and a with infections. For histopathological analysis were collected gill tissue, liver, kidney and skin of fish after the treatment of bacterial diseases with antibiotics. The water quality variables were recorded daily pH, temperature, electrical conductivity and dissolved oxygen in acute toxicity tests and during treatment. In tests of acute toxicity, the LC50;48h estimated of OTC for pacu was... (Complete abstract click electronic access below)

Submitted by Claudia Rocha (claudia.rocha@udesc.br) on 2018-03-06T13:11:14Z No. of bitstreams: 1 PGCS15MA136.pdf: 1486610 bytes, checksum: dcee4c1b36d86958950a37f58c8d8606 (MD5) / Made available in DSpace on 2018-03-06T13:11:14Z (GMT). No. of bitstreams: 1 PGCS15MA136.pdf: 1486610 bytes, checksum: dcee4c1b36d86958950a37f58c8d8606 (MD5) Previous issue date: 2015-08-15 / Capes / Apple crops have huge importance to South Brazil economic, which concentrate more than 95% production in country. There are use of many pesticides in apples, with emphasis to fungicide Mancozeb and insecticide Chlorpyrifos. Although these substances have been developed to acting in a specific group of organisms, they are potentially dangerous to all alive organisms direct or indirectly exposed. Depending on persistence and toxicity, pesticides could interfering in soil basics process, how respiration and fauna soils activity, that directly influence nutrients cycling, organic matter decomposition and improvement physical chemical characteristics, being this products a risk to soil. Not application only, but handle and cleaning of machines with residues are dangerous to environmental too, and could induce punctual contamination. In some countries, to complete degradation of this waste, there is a bed for biological degradation, called Biobeds. Ecotoxicoly is a tool that could be used to measure pesticide risks and from their wastes to environmental receptor – since microorganisms until superiors vertebrates, having international protocols to application of assays. The aim of this study, was investigate toxicity caused by Mancozeb and Chlorpyrifos in two different Oxisols, representatives to apple crops, and effluent of pulverizer tank with wastes, to establish risks doses to three organisms from soil - Folsomia candida (Colembolla), Enchytraeus crypticus (Enchytraedae) e Eisenia andrei (Lumbricidae), using ISO protocols, and analyses Biobeds about its toxicity to organisms after contamination, comparing to natural soils, observing use possibility in handle of pesticides with spill simulation. Chlorpyrifos show higher toxic than Mancozeb, especially to Collembola (LC < 1 mg kg-1). Earthworm, organism used in Brazil’s law to approve pesticides was less sensible than other 18 19 for both products. Lethal and reproduction assays showed different risk doses in soils. Biobeds reduced waste pesticide risks during time and this not happen in one natural soil, that indicate dissolving products its not enough to reduce or eliminate the risks for soil organisms. In spill simulation, Biobeds was efficient in eliminate toxicity to earthworms and enchytraeids, although, not to Collembola and long time assays are necessary to reduce Chlorpyrifos toxicity to this organism. Due to large number of active ingredients using in agriculture actually, deep impact pesticide studies in soil organisms are necessary and alternatives of this wastes discharge / O cultivo de maçã tem grande representatividade na economia da região Sul do Brasil e uma série de agrotóxicos é utilizada, destacando-se o fungicida Mancozebe e o inseticida Clorpirifós. Apesar de essas substâncias serem desenvolvidas para atuar em um conjunto de organismos alvo, são potencialmente danosas para todos os organismos vivos expostos aos produtos. Dependendo de sua persistência e toxicidade, os agrotóxicos podem interferir em processos básicos do solo, tais como a respiração e a atividade da fauna edáfica que reflete diretamente na ciclagem de nutrientes, decomposição da matéria orgânica e melhoria de atributos químicos e físicos, representando estes compostos um risco para o solo. O manuseio e limpeza de maquinário com resíduos o produto também são potencialmente perigosas ao ambiente, podendo causar contaminações pontuais. Em alguns países para a completa degradação deste resíduo, são utilizados leitos biológicos de descarte (Biobeds). A ecotoxicologia é uma ferramenta que pode ser utilizada para mensurar o risco dos agrotóxicos e seus resíduos a receptores ambientais. O objetivo desta dissertação foi avaliar a toxicidade causada pelos ingredientes ativos Mancozebe e Clorpirifós em dois solos representativos para a cultura da maçã no Sul do Brasil – Latossolo e Nitossolo, e do efluente do tanque pulverizador com resíduos destes produtos, a fim de estabelecer dosagens de risco a três organismos representantes da fauna edáfica – Folsomia candida (Colembolla), Enchytraeus crypticus (Enchytraedae) e Eisenia andrei (Lumbricidae), e analisar Biobeds quanto a sua toxicidade aos organismos após sua contaminação, quando comparado aos solos analisados, observando a possibilidade de uso dos Biobeds para descarte de efluentes de agrotóxicos e como contensão em caso de derrame acidental. Foram realizados ensaios laboratoriais utilizando 14 15 protocolos ISO para ensaios letais (14 dias) e subletais (28 dias para colêmbolos e enquitreídeos e 56 dias para minhocas) de ecotoxicidade com os organismos indicados em câmara a 20ºC e fotoperíodo com 8/16 horas de luz/escuro. O Clorpirifós mostrou-se mais tóxico que o Mancozebe, principalmente aos colêmbolos, que são afetados em ensaios letais e subletais por doses < 1 mg kg-1. As minhocas, únicos organismos utilizados na legislação brasileira para credenciamento de agrotóxicos no mercado mostraram-se menos sensíveis que os colêmbolos e enquitreídeos aos dois produtos testados para ensaios letais (CL50), e subletais de reprodução (CE50), que apresentaram doses de risco distintas, e o Latossolo apresentando maior toxicidade quando contaminado pelos agrotóxicos testados. Os Biobeds reduziram a toxicidade dos agrotóxicos ao longo do tempo para os organismos edáficos, o que não foi observado no Latossolo, mostrando que mesmo um resíduo muito diluído, como o da lavagem do equipamento de aplicação, pode oferecer risco a fauna do solo ao longo do tempo. Na simulação de derrame acidental, os Biobeds foram eficientes em eliminar a toxicidade para minhocas e enquitreídeos, mas não para os colêmbolos, sendo necessários ensaios a longo prazo para determinar a possibilidade de redução da toxicidade do Clorpirifós aos organismos nesta situação. Devido ao grande número de ingredientes ativos utilizados na agricultura atualmente, são necessários estudos mais profundos do impacto destes agentes químicos à fauna edáfica, e também das alternativas de descarte dos resíduos oriundos dessa atividade