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Development and validation of the marine benthic copepod Robertsonia propinqua as a bioindicator to monitor estuarine environmental healthHack, L. A. January 2008 (has links)
Studies in the USA have reported that species of meiobenthic copepods can be used as bioindicators of sediment-associated contaminants. The main objective of this research project was to develop and validate methods to assess the effects of estuarine pollution, using the marine benthic copepod Robertsonia propinqua as a bioindicator of environmental health in New Zealand intertidal / estuarine areas. Cultures of R. propinqua were set up and maintained in the laboratory and individuals used in 96h acute and full life-cycle chronic bioassays using the pre-selected contaminants atrazine and zinc sulphate. From the 96h acute experiments it was found that the lethal doses at which 50% mortality occurred (LC50) for exposed nauplii and adult individuals were 7.5 mg/L and 31.8 mg/L, respectively for atrazine and 1.7 mg/L and 2.7 mg/L, respectively for zinc sulphate. This indicated that the nauplii life stage was more sensitive than were the adult life stages for exposure to both contaminants. Based on the 'trigger' values reported (atrazine = 0.013 mg/L, zinc = 0.015 mg/L) in the Australian and New Zealand guidelines for fresh and marine water quality, which provide values at which concentrations of contaminants can occur in the environment before they begin causing effects on aquatic fauna, it is unlikely that the calculated LC50s in the current research will induce biological effects in exposed copepods in the short-term. The calculated LC50 results were then used to further investigate the effects of chronic exposure of sediment-associated contaminants on the complete life-cycle (egg-reproductive adult) of R. propinqua. In a laboratory-based full life-cycle toxicity test, field-collected sediments from polluted sites in the Auckland and Bay of Plenty regions reduced reproductive output (nauplii and copepodite production) of R. propinqua individuals, but the number of males and females, gravid females, clutch size per female and the number of eggs produced were not affected by either the polluted or non-polluted (reference) sediment samples from both field regions. Field investigations of meiofauna community composition in polluted and non-polluted field sites were carried out in 2004 in the Auckland and Bay of Plenty field regions in New Zealand. Greater sediment organic content and a correspondingly deeper redox potential discontinuity layer occurred in all polluted field sites compared with the non-polluted sites. However, species composition could not be used to characterise polluted and non-polluted sites, as there were no dominant taxa which were representative of these sites. The results presented in this thesis indicate that R. propinqua has strong potential to be a good candidate species as a bioindicator of environmental contamination. Furthermore, the full life-cycle toxicity test could be used as a rapid test to detect immediate changes in individual reproduction and development as well as long-term population effects. The technologies developed as part of this research may eventually provide additional tools for commercial environmental consultancies and may compliment existing standard operating procedures for environmental assessments involving pollution of estuarine ecosystems.
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Decision-making for acceptable risk in contaminated site problems in British ColumbiaThomas, Deanna 11 1900 (has links)
Contaminated sites are a common problem across municipalities in the Greater Vancouver Regional District. These problems are complicated and multi-dimensional, and raise fundamental concerns about the risks to human and environmental health. This thesis shows however, that there are no easy answers to how much risk is "acceptable", and no one right way to decide. How the acceptable risk problem is structured is important, because fact and value issues, a source of controversy and dispute, are variously interpreted depending on how the problem is cast. The literature generically categorizes acceptable risk as either a technical, social or decision problem, and each of these have implications for the types of decision-making approaches and solutions that are considered appropriate in resolving acceptable risk. This thesis investigated how acceptable risk in contaminated site problems is handled in British Columbia by reviewing the provincial decision-making framework, and by surveying municipalities in the Greater Vancouver Regional District for their views on contaminated site problems and acceptable risk decision-making. The underlying goal of the thesis is to question the use of the current approach, the Pacific Place site criteria, as a model for acceptable risk decision-making in the province, and to explore the implications for urban communities. The Ministry of Environment is the central authority for contaminated sites in British Columbia and has generally taken a scientific and technical approach to the problem. Although the municipal survey suggests that the Pacific Place site criteria has a broad base of support in the GVRD, the technical emphasis has implications for urban communities. The approach is expert-oriented and largely excludes local and public involvement in the acceptable risk debate. The major concern is that important social value issues have been neglected, relative to the engineering and technical aspects of the problem. The research also finds however, that the majority of individuals in the municipal survey are willing to explore other methods of determining acceptable risk, and support in principle, local government and public involvement in deciding what these methods should be. This thesis suggests that British Columbia can benefit from a more comprehensive view of acceptable risk in contaminated site problems. Resource limitations at the provincial and local level, and the high stakes in contaminated site problems for urban communities point to the growing importance of incorporating a broad range of value issues and understanding the trade-offs in acceptable risk decisions. The Ministry of Environment can improve the current decision-making approach by: incorporating structured value assessments that elicit stakeholder values and address trade-offs; involving a wider range of stakeholders in standard setting and risk assessment, including the forthcoming review of the Pacific Place site criteria; creating forums to explore other decision-making approaches; and by encouraging private sector involvement in risk assessment and risk management. The province can also encourage and support community-based institutional networks, both at the municipal and regional level.
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Decision-making for acceptable risk in contaminated site problems in British ColumbiaThomas, Deanna 11 1900 (has links)
Contaminated sites are a common problem across municipalities in the Greater Vancouver Regional District. These problems are complicated and multi-dimensional, and raise fundamental concerns about the risks to human and environmental health. This thesis shows however, that there are no easy answers to how much risk is "acceptable", and no one right way to decide. How the acceptable risk problem is structured is important, because fact and value issues, a source of controversy and dispute, are variously interpreted depending on how the problem is cast. The literature generically categorizes acceptable risk as either a technical, social or decision problem, and each of these have implications for the types of decision-making approaches and solutions that are considered appropriate in resolving acceptable risk. This thesis investigated how acceptable risk in contaminated site problems is handled in British Columbia by reviewing the provincial decision-making framework, and by surveying municipalities in the Greater Vancouver Regional District for their views on contaminated site problems and acceptable risk decision-making. The underlying goal of the thesis is to question the use of the current approach, the Pacific Place site criteria, as a model for acceptable risk decision-making in the province, and to explore the implications for urban communities. The Ministry of Environment is the central authority for contaminated sites in British Columbia and has generally taken a scientific and technical approach to the problem. Although the municipal survey suggests that the Pacific Place site criteria has a broad base of support in the GVRD, the technical emphasis has implications for urban communities. The approach is expert-oriented and largely excludes local and public involvement in the acceptable risk debate. The major concern is that important social value issues have been neglected, relative to the engineering and technical aspects of the problem. The research also finds however, that the majority of individuals in the municipal survey are willing to explore other methods of determining acceptable risk, and support in principle, local government and public involvement in deciding what these methods should be. This thesis suggests that British Columbia can benefit from a more comprehensive view of acceptable risk in contaminated site problems. Resource limitations at the provincial and local level, and the high stakes in contaminated site problems for urban communities point to the growing importance of incorporating a broad range of value issues and understanding the trade-offs in acceptable risk decisions. The Ministry of Environment can improve the current decision-making approach by: incorporating structured value assessments that elicit stakeholder values and address trade-offs; involving a wider range of stakeholders in standard setting and risk assessment, including the forthcoming review of the Pacific Place site criteria; creating forums to explore other decision-making approaches; and by encouraging private sector involvement in risk assessment and risk management. The province can also encourage and support community-based institutional networks, both at the municipal and regional level. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate
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<b>Development of a Variable Dilution Olfaction Chamber Coupled with a Proton Transfer Reaction Mass Spectrometer for Evaluation of Human Response to Indoor Emissions from Scented Volatile Chemical Products</b>Jordan N Cross (16700061) 02 August 2023 (has links)
<p>This study is focused on the design, production, and operation of a controlled environmental olfaction chamber to evaluate human physiological and emotional response to volatile chemical emissions (VCPs) from scented household products in addition to careful characterization of the volatile organic compounds (VOCs) present in these product emissions. Utilizing proton transfer reaction time-of-flight mass spectrometry, the chamber can collect VCP emissions and identify VOCs present to complete an accurate chemical profile of household and common product emissions not previously known. This instrument is one of the first of its kind and will serve as a key element in understanding the relationship between human physical and cognitive health and the built environment.</p>
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