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Effects of the sea lice chemotherapeutant cypermethrin on marine zooplanktonMedina, MatiÌas January 2002 (has links)
No description available.
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Knowledge management and environmental managementMiles, Leon Anthony January 2000 (has links)
No description available.
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Assessing the roles of anti-androgenic and oestrogenic mixtures on endocrine disruption in fishGreen, Christopher January 2014 (has links)
Incidence of endocrine disruption in wild fish species has been documented globally and is well characterised in the UK, where the occurrence of intersex in roach (Rutilus rutilus) is widespread. Although this has been associated with concentrations of steroid oestrogens, research indicates that anti-androgenic chemicals may also play a role in inducing these effects. Anti-androgenic activity is commonly detected in wastewater treatment works effluents and some receiving waters, but the chemicals responsible remain largely uncharacterised. This thesis aimed to identify environmental anti-androgens in UK and South Australian catchments and to produce environmentally relevant exposures to assess their potential impacts on sexual disruption in fish, alone and in combination with steroid oestrogens. By using hydrological modelling techniques, pharmaceuticals with an anti-androgenic mode of action were predicted to occur in the ng/L concentration range in UK and South Australian wastewater treatment works effluents and river catchments. This work included analysis of future trends in environmental concentrations of the pharmaceuticals and the steroid oestrogens in these catchments. Modest increases in concentrations by 2050 were predicted in the absence of mitigation, which could increase in the risk posed to fish health by the steroid oestrogens in the future. The effects of the predicted concentrations of two pharmaceuticals, bicalutamide and cyproterone acetate, were then assessed in fathead minnows (Pimephales promelas) and Japanese medaka (Oryzias latipes) based on the UK modelling for the present day. These concentrations did not contribute to endpoints characteristic of sexual disruption, alone or in combination with steroid oestrogens. However, the results did support an environmental role for the steroid oestrogens in intersex induction. Concurrently, effect directed analysis identified some highly potent anti-androgens, such as triclosan and pyrene, in wastewater treatment works effluents from the UK. However, they are likely to make a minor contribution to overall anti-androgenic activity due to their low concentrations. Consequently, more work is required to identify the causes of this activity in the environment and its implications for wild fish health.
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Environmental analysis and assessment of biocides used in antifouling paints as alternatives to organotin compoundsVoulvoulis, Nikolaos January 2000 (has links)
No description available.
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A Comparison of the Carbon Dioxide and Oxygen Rate of Change Methods for Measuring Primary ProductivityTrotter, Dennis M. 05 1900 (has links)
The purpose of this study was to demonstrate the variability of oxygen and carbon dioxide rate of change methods for measuring primary productivity and respiration in an aquatic environment.
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Metabolic enzymes and mixed-function oxygenase (MFO) system in pink snapper (Pagrus auratus): biochemical and histological relationshipsTugiyono, January 2001 (has links)
The environmental health of aquatic ecosystems depends amongst others, on the chemical pollution coming from activities in the catchment's area. In the Swan River Estuary, Western Australia, the chemical pollutants of concern released into the river are petroleum hydrocarbons and sodium pentachlorophenate (NaPCP). Decreased water quality causes a loss of biotic diversity especially amongst fish populations. The health of aquatic ecosystems can be monitored by fish health, especially fish located at higher levels in the food chain. Pink snapper (Pagrus auratus), an endemic Western Australian fish species, was tested for its potential as a bioindicator of aquatic environmental health. This thesis presents data on the responsiveness of pink snapper to the contaminants of concern, using biomarkers such as serum sorbitol dehydrogenase (SDH), mixed function oxygenase (MFO), metabolic enzymes such as citrate synthase (CS), cytochrome C oxidase (CCO) and lactate dehydrogenase (LDH) and the histological alteration such as hepatic cell lesions (hyperplasia and hypertrophy), and glycogen and lipid droplets. The metabolic enzymes CCO and LDH as well as the hepatic MFO induction and histopathology were proven to be the most suitable biomarkers for use for routine monitoring of the Swan River Estuary using pink snapper as a bioindicator. However, CS activity and hepatic cell lesions (hyperplasia and hypertrophy) did not respond to exposure to contamination and are therefore not suited as biomarkers of effects in pink snapper. The first phase of the study aimed at investigating the responsiveness of juvenile pink snapper to an MFO inducer. Polychlorinated biphenyl isomer # 126 was selected as a model MFO inducer for this study. In the initial experiment, MFO activity was measured as a biomarker of exposure, and serum SDH activity was assessed as a biomarker of liver damage. / MFO and SDH activities were of special interest as these biochemical tools have not previously been validated for any Western Australia fish species. Juvenile pink snapper were injected intraperitoneally (i.p.) with 0, 10, 100, 500, 1000 microgram PCB-126 per kilogram. Fish were sacrificed 10 days postinjection, and liver and blood were collected for MFO and SDH analysis, respectively. Doses of 10 and 100 microgram PCB-126 per kilogram caused the highest MFO induction, while doses of 0 and 1000 microgram PCB-126 per kilogram did not result in higher MFO activity relative to carrier-injected (peanut oil) control fish. SDH activities were not significantly different among treatments indicating that hepatocellular damage was not responsible for the reduced MFO activity at the highest dose. Metabolic enzymes in pink snapper exposed by NaPCP were studied in the second phase of the experiment. The aim of this second experiment was to test the responsiveness of pink snapper to contaminants known to cause metabolic perturbations in vertebrates. Juvenile pink snapper were intraperitoneally (i.p.) injected with 0, 5, 10, 20 mg per kilogram. Oxidative enzymes were assessed by measuring CS and CCO activities and glycolytic enzyme was assessed by measuring LDI-1 activity in liver and white muscle tissues. CS activity remained unchanged in both the white muscle and in the liver. CCO activity was significantly enhanced in liver in all treated fish relative to control fish, but not in the white muscle. LDH activity was also higher in liver in all treated fish as compared to control fish, while in white muscle, LDH activity significantly increased at the highest dose injected. / The use of a suite of biochemical markers is useful in determining the effects of xenobiotic exposure of aquatic organisms, because it provides a holistic approach with biomarkers at different levels of biological organization. For the third and final phase of the study the suite of biomarkers selected were MFO, metabolic enzyme (CS, CCO and LDH) activities, and histological alternations in combination with physiological indices. The aim of this last experiment was to investigate if a modified liver metabolic activity would alter the MFO induction potential. To test if altered liver metabolism would influence liver detoxication capacities, juvenile pink snapper were i.p. injected with peanut oil (control), or pentachlorobiphenyl # 126 (PCB 126), with sodium pentachlorophenate (NaPCP), or combination of PCB 126+NaPCP. Relative to controls, ethoxyresorufin-O-deethylase (EROD) activity was induced in the PCB 126 and PCB 126+NaPCP fish, but not in the NaPCP group. In the liver, CCO activity was enhanced by the treatments while CS activity remained unchanged and LDH activity was increased in the NaPCP treatment only. In the white muscle, only the PCB 126+ NaPCP treatment enhanced CCO activity, with all other enzymatic activities remaining unchanged. Low serum sorbitol dehydrogenase (sSDH) activity and histopathology of the liver indicated no significant alteration of cellular structure, albeit the lipid droplet size was increased in the PCB 126 and in the PCB 126+NaPCP treatments. / It is concluded that the hepatic metabolic changes correspond to histopathological observations, but an altered metabolic capacity does not influence the metabolism of xenobiotics by liver enzymes, as measured by EROD activity. These experiments answered the need to identify a suitable fish species for routine monitoring of the aquatic environment in Western Australia. It also identified the most suitable biochemical markers of exposure and effects, and the suitability of the pink snapper as a bioindicator. Finally, the experiments investigated interactions between biomarkers and provided new knowledge useful to scientists using MFO and/or metabolic enzymes in field or laboratory toxicology.
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Strategy analysis for ecological restoration and water pollution control of Love River aquatic environment in Kaohsiung regionLee, Meng-Tsung 26 July 2002 (has links)
Following the economy growth and commercial and industrial development, the rivers in Taiwan have suffered the environmental degradation due to the overwhelming pollution from domestic and industrial sewage. Recent environmental awareness from the citizen has turned the once ignored issues of pollution mitigation and ecological restoration into the public attention. Traditionally, resort to engineering efforts is always the first priority in dealing with river pollution problem. Nevertheless, treated as the integrated system, the nature of the problem should involve many aspects including social, economic, ecological, environmental, and engineering factors. Meanwhile, the special feature of time-dependent state has also made such system a dynamic and complex problem. It is therefore the current research employs the approach from integrated assessment trying to aggregate related studies and tackling the problem as a complete system. System dynamic, which is capable of dealing with dynamic and complex problems, has been utilized as the simulation tool in this research. The result from computer simulation can be promptly generated, and various scenario analyses can be easily achieved by modifying the model parameters to support better decision-making.
Love River wandering through the Kaohsiung metropolitan area is the research target. The system dynamic software STELLA has been used to construct the simulation model, which incorporates water quality model, population growth in the upstream of the watershed, land use variation due to the assumed regional development, diverse rainfall types, ecological assessment of the domestic fishes in the river, and cost-benefit of various pollution control strategies. The system dynamic models are thus able to evaluate the overall impact on the aquatic environment between various management scenarios. Two types of system dynamic models are constructed and verified accordingly to evaluate the impact of the designate gate operations and the sewage treatment strategies on aquatic environment.
The simulation based on the gate operation model shows that keeping upper stream gates shut during the initial time span of a rainfall event would have the better effect to prolong the concentration of dissolved oxygen (DO) downs to the lethal concentration (LC50) for the local fish species. In the sewage treatment strategies model, the treatment cost and effect is the primary concern. The results identify the better extending strategy on the treatment plant, which is to use fortified primary treatment by adding disinfectant facilities. The other scenario of building constructed wetland system on the public park can improve water quality with good cost/effect ratio given the land acquisition is not an issue.
Keyword¡GIntegrated Assessment, System Dynamic, Sustainable River Aquatic Environment
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The effect of different water types on the survival and eclosion rate of submerged Lucilia sericata pupaeRobinson, Sakura 25 October 2018 (has links)
Blowflies (Diptera: Calliphoridae) are main colonizers of decomposing remains and any information on the influences of their lifecycle of growth and development are important to forensic entomologists when estimating postmortem interval during a medicolegal death investigation. Pupal survival of blowfly species, Lucilia sericata were studied at different developmental stages following pupation, white (0-12 hrs), young (24 hrs), medium (5 days), old (9 days) were submerged at various immersion intervals ranging from 1 hr to 120 hr (5 days) in different water types (fresh, salt, polluted, and drinking water). Control group (N= 100) were white pupae that were not submerged were also observed in order to compare the survival and eclosion rate. Two trials of the submergence process were conducted to observe the pupae survival. Data were analyzed using multiple logistic regressions in a 3-way interaction to determine if significant differences were seen between the water, time in water, and pupal stage. Dissolved inorganic nitrogen (DIN) of NH4+, NO2-, NO3-, and oP or DIP were analyzed to examine to determine if a correlation between the water types could be seen. DIN analyses exhibited similar NO2- + NO3- and NO3- in polluted and fresh water. The results show that as the pupae developmental age progressed, the pupae generally survived longer immersion intervals. The survival of white pupae decreased with the increase of submergence for all four water types, exhibiting a 100%mortality rate with pupae submerged longer than 24-36 hours. While pupae immersed in polluted water had similar survival rates in the white stage, the survival rate declined as the developmental age increased for pupae immersed in polluted water. Pupae immersed in salt and polluted water had earlier eclosion times when compared to other water groups, emerging at 36 hours from when the control group first emerged at day 12. Understanding the survival rate of submerged Lucilia sericata (Diperta: Calliphoridae) pupae will be potentially useful for criminal investigations by providing a better understanding of the survival of pupae submerged in different aquatic environments.
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Ecotoxicidade de corantes e de produtos de tratamento oxidativo avançado = Ecotoxicity of dyes and their products generated by advanced oxidative treatment / Ecotoxicity of dyes and their products generated by advanced oxidative treatmentLuna, Luis Augusto Visani, 1985- 12 March 2012 (has links)
Orientadores: Gisela de Aragão Umbuzeiro, Fábio Kummrow / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Tecnologia / Made available in DSpace on 2018-08-21T17:09:36Z (GMT). No. of bitstreams: 1
Luna_LuisAugustoVisanide_M.pdf: 1874744 bytes, checksum: 77b303f234e135332fe2eb3247fedaca (MD5)
Previous issue date: 2012 / Resumo: Corantes possuem uma grande diversidade de estruturas e aplicações, estando presentes em diversos setores indústriais. Os corantes podem contaminar os ambientes aquáticos após os despejos de efluentes de indústrias têxteis, de alimentos, de curtumes e até mesmo de lavanderias. Muitos corantes apresentam elevada toxicidade para organismos aquáticos, no entanto processos de tratamento de efluentes contendo corantes estão sendo desenvolvidos no intuito de impedir seu ingresso no ambiente, e dentre eles estão os processos oxidativos avançados. No presente estudo, foi avaliada a toxicidade de corantes têxteis e alimentícios para organismos aquáticos, antes e após o tratamento oxidativo avançado foto-Fenton. Foram realizados testes de toxicidade com Daphnia similis, Ceriodaphnia dubia e Pseudokirchneriella subcapitata. A partir dos dados obtidos nos ensaios de toxicidade com os produtos comerciais os corante têxteis foram considerados os mais tóxicos, em especial o corante C.I. Vat Green 3. Para os ensaios com os produtos de degradação gerados, o tratamento do corante C.I. Acid Orange 7 gerou intermediários tóxicos para D. similis, no entanto ao final do tratamento não foi observada toxicidade. Após o tratamento do corante C.I. Reactive Black 5 foi observada toxicidade para P. subcapitata, sendo esta maior que a toxicidade para o produto comercial. No início do tratamento do corante C.I. Vat Green 3 ocorreu uma redução da toxicidade para D. similis e para P. subcapitata em relação ao produto comercial, contudo no final do tratamento a toxicidade observada foi maior que a do produto comercial para ambos os organismos. Considerando os corantes alimentícios, para o C.I. Food Yellow 3 tratado não foi observada toxicidade para D. similis nas concentrações estudadas, no entanto para P. subcapitata foi observado toxicidade ao final do tratamento. O corante C.I. Food Red 17 foi tóxico no início do tratamento tanto para D. similis, quanto para P. subcapitata, mas no fim do tratamento não foi mais observada toxicidade / Abstract: Dyes have a wide diversity of structures and uses, and then these substances are present in many industrial sectors. Dyes also can be found as contaminants in aquatic environments after wastewater discharge of textile industries, food industries, tanneries and laundries. Many dyes can be toxic to aquatic organisms. Several treatments have been proposed to remove dyes from effluents preventing the surface water contamination and one of the most promising tools are the advanced oxidative treatments. The aim of this study was to assess the toxicity of textile and food dyes to aquatic organisms, before and after photo - Fenton. We employed tests with the freshwater organisms, Daphnia similis, Ceriodaphnia dubia and Pseudokirchneriella subcapitata. The dye C.I. Vat green 3 was considered the most toxic dye among the commercial dyes tested in this study. Taking into account the treatment of the commercial products and the toxicity tests, the treatment of C.I. Acid Orange 7 generated toxic intermediates for D. similis, but at the end of the treatment no toxicity was observed. After the C.I. Reactive Black 5 treatment greater toxicity was observed to P. subcapitata in comparison with the commercial dye toxicity. At the beginning of the C.I. Vat Green 3 treatement the toxicity was lower than the commercial dye to D. similis and P. subcapitata, but at the end of the treatment the toxicity was higher than the commercial dye for both organisms. For the food dye C.I. Food Yellow 3 treated, was not observed toxicity for D. similis, but at the end of the treatment toxicity was observed for P. subcapitata. The dye C.I Food Red 17 was toxic to D. similis and P. subcapitata at the beginning of the treatment, but at the end of the treatment no toxicity was observed / Mestrado / Tecnologia e Inovação / Mestre em Tecnologia
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Effects of pharmaceuticals in fish : in vitro and in vivo studiesCorcoran, Jenna Frances January 2013 (has links)
Fish may be exposed to an array of pharmaceuticals that are discharged into the aquatic environment, paralleling advances in medical knowledge, research and technology. Pharmaceuticals by their nature are designed to target specific receptors, transporters, or enzymes. Nuclear receptors (NRs) are often a key component of the therapeutic mechanism at play, and many of these are conserved among vertebrates. Consequently, fish may be affected by environmental pharmaceutical exposure, however there has been relatively little characterisation of NRs in fish compared with in mammals. In this thesis common carp (C. carpio) were exposed to selected pharmaceuticals in vitro and in vivo to investigate effects centred on the pregnane X receptor (PXR) and peroxisome proliferator-activated receptor alpha (PPARα), two key NRs involved in organism responses to pharmaceutical exposure. The PXR acts as a xenosensor, modulating expression of a number of xenobiotic metabolising enzymes (XMEs) in mammals. In a primary carp hepatocyte model it was shown that expression of a number of XMEs was altered on exposure to rifampicin (RIF), as occurs in mammals. This response was repressed by addition of ketoconaozle (KET; PXR-antagonist), indicating possible PXR involvement. The genes analysed showed up-regulation on exposure to ibuprofen (IBU) and clofibric acid (CFA), but not clotrimazole (CTZ) or propranolol (PRP). The lack of response to mammalian PXR-agonist CTZ was unexpected. In contrast, the same XME genes were found to be up-regulated in vivo after 10 days of exposure of carp to CTZ, although this response occurred only for a relatively high exposure concentration. CTZ was found to concentrate in the plasma (with levels up to 40 times higher than the water). Development and application of a reporter gene assay to measure PXR activation in carp (cPXR) and human PXR showed CTZ activation of cPXR, supporting data from the in vivo studies. Furthermore, activation was seen at concentrations as low as 0.01 μM. Interestingly RIF did not induce a response in the cPXR reporter gene assay, contrasting with the hepatocyte culture work. Taken together, the data presented here suggests divergence in the PXR pathway between mammals and fish in terms of ligand activation and downstream gene targets. PPARα was investigated in carp in vivo using CFA as a mammalian PPARα-agonist. Overall the resulting data suggested a broadly similar role for this NR in lipid homeostasis in fish as for mammals, with a number of PPARα-associated genes and acyl-coA oxidase (ACOX1) activity up-regulated in response to CFA exposure. A number of XMEs were also up-regulated by CFA (in vivo and in vitro), potentially extending the role of PPARα in fish (carp) to regulation of xenobiotic metabolism. The work presented has provided further characterisation of PXR and PPARα in fish. Elucidation of these pathways is vital to provide meaningful data in terms of establishing toxicity and mechanism-of-action data for pharmaceuticals and other compounds in fish, to allow validation of read-across approaches and ultimately aid in their environmental risk assessment. In vitro approaches are attractive ethically, financially and can provide useful mechanistic characterisation of compounds and the primary hepatocyte model and reporter gene assays used here show potential for the screening of pharmaceutical compounds in fish. However, further understanding of the metabolism of drugs and chemicals in fish is required to establish the true value of these methods for informing on possible effects in fish, in vivo.
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