Na região do Vale do Ribeira, os resíduos de mineração foram dispostos diretamente sobre o solo, nas proximidades da empresa responsável pelo beneficiamento e fundição do minério de chumbo (Pb) (próximo à Vila Operária – município de Adrianópolis-PR). A escória de fundição enriquecida em metais potencialmente tóxicos (MPT), primeiramente foi disposta na forma de pilha. Em 2006, parte desta escória foi transferida para um aterro de resíduo sólido localizado a 50 m do antigo depósito e parte continuou no antigo local de disposição. As escórias que continuaram no antigo local foram espalhadas e cobertas com um solo residual. Esta cobertura não foi realizada de forma adequada, sendo que em algumas porções da área é possível ver as escórias, estando estas em contato direto com os animais (principalmente, ovinos e bovinos). Visando avaliar a influência da disposição das escórias na contaminação do solo de superfície e basal, foram coletadas amostras em distintas profundidades e em duas linhas de caminhamento principais (NS e EW) na área da antiga disposição. Nestas amostras foram realizadas caracterizações geotécnicas, geoquímicas e microbiológicas. Os ensaios realizados foram: granulometria conjunta, limites de Atterberg, capacidade de troca catiônica (CTC) e superfície específica (SE), matéria orgânica (MO), potencial hidrogeniônico (pH), potencial redox (Eh), condutividade elétrica (CE), delta pH (ΔpH), microscopia eletrônica de varredura com espectrômetro de energia dispersiva acoplado (MEV/EDS), mineralogia por difração de raios-x (DRX), fluorescência de raios-x (FRX), determinação da concentração pseudo-total (absorção atômica – AA; espectrometria de emissão atômica - ICP/AES), solubilização, lixiviação, extração sequencial, avaliação da comunidade microbiana por RCP-EEGD (ou PCR-DGGE) e sequenciamento do gene RNAr 16S via ILLUMINA. A avaliação da contaminação foi realizada considerando índice de geoacumulação (Igeo ), fator de enriquecimento (FE ou EF), Código de Avaliação de Risco (CAR ou RAC) e potencial de risco ecológico (Eir). O pH em H2O observado no depósito foi de 6,5 a 7,6, indicando que o meio é ligeiramente ácido. Já o Eh foi considerado oxidante. A CE foi especialmente elevada nas amostras superficiais (0-20 cm) e nos perfis coletados na linha de caminhamento EW. A CTC média foi de 14,3 cmolc/kg, sendo esta característica da caulinita. Quanto ao teor de matéria orgânica observou-se variação de 0,3 a 5,4 g/kg, sendo o valor médio de 2,14 g/kg. A base do depósito possui média de 68% de finos e índice de plasticidade de 2 a 35%. Para a base do depósito (de 60 a 100 cm) observou-se concentrações pseudo-totais de MPT bem inferiores ao topo. Em relação ao solo superficial observou-se elevada concentração pseudo-total, principalmente de Pb (média de 6.268,85 mg/kg) e Zn (média de 20.261,50 mg/kg). As concentrações de Cd observadas foram acima dos valores de background da área (média de 12,19 mg/kg). A concentração de MPT nas amostras coletadas na linha de caminhamento EW foram superiores às de NS, estando mais elevadas naquelas mais próximas à antiga empresa de beneficiamento. A partir dos ensaios de solubilização, lixiviação e extração sequencial, notou-se que o Pb e o Cd estão mais prontamente solúveis. Verificou-se para o Cd menor concentração pseudo-total, quando comparado com o Pb e Zn, todavia, observou-se para esse metal maior índice de geoacumulação, maior risco ecológico e maior mobilidade. A ordem obtida para os MPT, de acordo com o risco potencial, utilizando as frações mais móveis foi Cd > Pb ≈ Zn. Obteve-se maior diversidade e riqueza bacteriana nas amostras com maior concentração pseudo-total de metais, maior Igeo e maior Eir . Nas amostras superficiais foram identificadas bactérias tolerantes a presença de MPT, como Rhodoplanes, Kaistobacter, Sphingomonas, Flavobacterium, Cellvibrio, Rheinhermera e Pseudomonas. Assim, conclui-se que a porção superficial do perfil e mais próxima a empresa que beneficiou o minério está mais contaminada e com maior risco que a basal. A partir desses resultados pode-se inferir que a integração de conhecimentos é fundamental na avaliação da contaminação em áreas de mineração. / In the Ribeira Valley region, mining wastes were placed directly on the soil near the company responsible for the processing and smelting of lead ore (Pb) (near of the Vila Operária – Adrianópolis-PR). The slag enriched in potentially toxic metals (PTM) was initially deposited in piles. In 2006 part of the slag was moved to a solid waste landfill located 50 m from the old deposit and part remained at the former disposal site. The slag that remained in the old deposit were spread out evenly and covered with a residual soil. This coverage was not performed adequately, and in some areas of the deposit the slag is on the soil surface, being in direct contact with animals (mainly sheep and cattle). In order to assess the contamination of slag disposal on soil, samples were collected at various depths and in two main transverse lines (NS and EW) in the area of the old deposit. Geotechnical, geochemical and microbiological characterization were performed in these samples. The assays carried out were: granulometry, Atterberg limits, cation exchange capacity (CEC) and specific surface (SS), organic matter (OM) content, hydrogenation potential (pH), redox potential (Eh), electrical conductivity (EC), delta pH (ΔpH), scanning electron microscopy coupled with energy dispersive spectrometer (SEM/EDS), mineralogy using X-ray diffraction (XRD), x-ray fluorescence (XRF), determination of pseudo-total concentration (atomic absorption - AA; inductively coupled plasma atomic emission spectroscopy - ICP/AES), solubilization, leaching, sequential extraction, microbial community evaluation by PCR-DGGE and sequencing of the 16S RNAr gene via ILLUMINA. The evaluation of the contamination was conducted using the geoaccumulation index (Igeo), enrichment factor (EF), Risk Assessment Code (RAC) and potential ecological risk (Eir). The mean pH in H2O observed in the deposit varied from 6.5 to 7.6 (slightly acid) and Eh was considered oxidant. EC was especially high in the surficial samples (0-20 cm) and in the profiles collected in the EW transverse line. The medium CEC was 14.3 cmolc/kg, characteristic of kaolinite. The organic matter content varied from 0.3 to 5.4 g/kg, with a mean value of 2.14 g/kg. The base of the deposit is constituted with a medium of 68% of fines and plasticity index of 2-35%. It was observed that the base of the deposit (60 to 100 cm) has a considerably lower pseudo-total concentration of PTM when compared to the topsoil. In the surficial soil it was observed high pseudo-total concentration, mainly Pb (mean of 6,268.85 mg/kg) and Zn (mean of 20,261.50 mg/kg). The Cd concentrations were above the background values of the area (mean of 12.19 mg/kg). The PTM concentration in samples collected in the EW transverse line were higher than those of NS, being specially higher in the samples closer to the former beneficiation company. According to the results obtained from the solubilization, leaching and sequential extraction assays, it was noted that Pb and Cd are more readily soluble. A lower pseudo-total concentration was observed for Cd, when compared to Pb and Zn, however, a higher geoaccumulation index, greater ecological risk and greater mobility was observed for this metal. The order for PTM, according to the potential risk, using the more mobile fractions was Cd > Pb ≈ Zn. Greater diversity and bacterial richness were obtained in the samples with higher pseudo-total concentration of metals, higher Igeo and greater Eir. In the surficial samples, bacteria tolerant to the presence of PTM, such as Rhodoplanes, Kaistobacter, Sphingomonas, Flavobacterium, Cellvibrio, Rheinhermera and Pseudomonas were identified. Thus, it is concluded that the surface portion of the profile closer to the former smelting company is more contaminated and with greater risk than the basal portion. From the results it can be inferred that the integration of knowledge is fundamental in the evaluation of the contamination in mining areas.

Uncertainty is pervasive in risk assessment. In ecotoxicological risk assessments, it arises from such sources as a lack of data, the simplification and abstraction of complex situations, and ambiguities in assessment endpoints (Burgman 2005; Suter 1993). When evaluating and managing risks, uncertainty needs to be explicitly considered in order to avoid erroneous decisions and to be able to make statements about the confidence that we can place in risk estimates. Although informative, previous approaches to dealing with uncertainty in ecotoxicological modelling have been found to be limited, inconsistent and often based on assumptions that may be false (Ferson & Ginzburg 1996; Suter 1998; Suter et al. 2002; van der Hoeven 2004; van Straalen 2002a; Verdonck et al. 2003a). In this thesis a Generalised Linear Modelling approach is proposed as an alternative, congruous framework for the analysis and prediction of a wide range of ecotoxicological effects. This approach was used to investigate the results of toxicity experiments on the effect of 2,4-Dichlorophenoxyacetic Acid (2,4-D) formulations and 4-Chlorophenol (4-CP, an associated breakdown product) on Daphnia carinata. Differences between frequentist Maximum Likelihood (ML) and Bayesian Markov-Chain Monte-Carlo (MCMC) approaches to statistical reasoning and model estimation were also investigated. These approaches are inferentially disparate and place different emphasis on aleatory and epistemic uncertainty (O'Hagan 2004). Bayesian MCMC and Probability Bounds Analysis methods for propagating uncertainty in risk models are also compared for the first time. For simple models, Bayesian and frequentist approaches to Generalised Linear Model (GLM) estimation were found to produce very similar results when non-informative prior distributions were used for the Bayesian models. Potency estimates and regression parameters were found to be similar for identical models, signifying that Bayesian MCMC techniques are at least a suitable and objective replacement for frequentist ML for the analysis of exposureresponse data. Applications of these techniques demonstrated that Amicide formulations of 2,4-D are more toxic to Daphnia than their unformulated, Technical Acid parent. Different results were obtained from Bayesian MCMC and ML methods when more complex models and data structures were considered. In the analysis of 4-CP toxicity, the treatment of 2 different factors as fixed or random in standard and Mixed-Effect models was found to affect variance estimates to the degree that different conclusions would be drawn from the same model, fit to the same data. Associated discrepancies in the treatment of overdispersion between ML and Bayesian MCMC analyses were also found to affect results. Bayesian MCMC techniques were found to be superior to the ML ones employed for the analysis of complex models because they enabled the correct formulation of hierarchical (nested) datastructures within a binomial logistic GLM. Application of these techniques to the analysis of results from 4-CP toxicity testing on two strains of Daphnia carinata found that between-experiment variability was greater than that within-experiments or between-strains. Perhaps surprisingly, this indicated that long-term laboratory culture had not significantly affected the sensitivity of one strain when compared to cultures of another strain that had recently been established from field populations. The results from this analysis highlighted the need for repetition of experiments, proper model formulation in complex analyses and careful consideration of the effects of pooling data on characterising variability and uncertainty. The GLM framework was used to develop three dimensional surface models of the effects of different length pulse exposures, and subsequent delayed toxicity, of 4-CP on Daphnia. These models described the relationship between exposure duration and intensity (concentration) on toxicity, and were constructed for both pulse and delayed effects. Statistical analysis of these models found that significant delayed effects occurred following the full range of pulse exposure durations, and that both exposure duration and intensity interacted significantly and concurrently with the delayed effect. These results indicated that failure to consider delayed toxicity could lead to significant underestimation of the effects of pulse exposure, and therefore increase uncertainty in risk assessments. A number of new approaches to modelling ecotoxicological risk and to propagating uncertainty were also developed and applied in this thesis. In the first of these, a method for describing and propagating uncertainty in conventional Species Sensitivity Distribution (SSD) models was described. This utilised Probability Bounds Analysis to construct a nonparametric 'probability box' on an SSD based on EC05 estimates and their confidence intervals. Predictions from this uncertain SSD and the confidence interval extrapolation methods described by Aldenberg and colleagues (2000; 2002a) were compared. It was found that the extrapolation techniques underestimated the width of uncertainty (confidence) intervals by 63% and the upper bound by 65%, when compared to the Probability Bounds (P3 Bounds) approach, which was based on actual confidence estimates derived from the original data. An alternative approach to formulating ecotoxicological risk modelling was also proposed and was based on a Binomial GLM. In this formulation, the model is first fit to the available data in order to derive mean and uncertainty estimates for the parameters. This 'uncertain' GLM model is then used to predict the risk of effect from possible or observed exposure distributions. This risk is described as a whole distribution, with a central tendency and uncertainty bounds derived from the original data and the exposure distribution (if this is also 'uncertain'). Bayesian and P-Bounds approaches to propagating uncertainty in this model were compared using an example of the risk of exposure to a hypothetical (uncertain) distribution of 4-CP for the two Daphnia strains studied. This comparison found that the Bayesian and P-Bounds approaches produced very similar mean and uncertainty estimates, with the P-bounds intervals always being wider than the Bayesian ones. This difference is due to the different methods for dealing with dependencies between model parameters by the two approaches, and is confirmation that the P-bounds approach is better suited to situations where data and knowledge are scarce. The advantages of the Bayesian risk assessment and uncertainty propagation method developed are that it allows calculation of the likelihood of any effect occurring, not just the (probability)bounds, and that the same software (WinBugs) and model construction may be used to fit regression models and predict risks simultaneously. The GLM risk modelling approaches developed here are able to explain a wide range of response shapes (including hormesis) and underlying (non-normal) distributions, and do not involve expression of the exposure-response as a probability distribution, hence solving a number of problems found with previous formulations of ecotoxicological risk. The approaches developed can also be easily extended to describe communities, include modifying factors, mixed-effects, population growth, carrying capacity and a range of other variables of interest in ecotoxicological risk assessments. While the lack of data on the toxicological effects of chemicals is the most significant source of uncertainty in ecotoxicological risk assessments today, methods such as those described here can assist by quantifying that uncertainty so that it can be communicated to stakeholders and decision makers. As new information becomes available, these techniques can be used to develop more complex models that will help to bridge the gap between the bioassay and the ecosystem.

The aim of this study was to understand the contribution of Linear Alkylbenzene Sulfonates (LAS) to the decline of Mediterranean coastal forest exposed to marine aerosols. LAS are a group of synthetic anionic surfactants widely used in the composition of household or industrial detergents and agrochemicals. This study was part of a large project (RISICO) aiming the assessment of the environmental impact of the LAS at multiple levels: biodegradation in the coastal waters, sorption – desorption processes in the sediments, toxicity to the aquatic life and toxicity to the coastal forest (by aerosolisation of the sea water). <p>Previous studies pointed out this group of surfactants as the main cause of the coastal forest decline. However, the quantification of this surfactant in the environmental samples (mainly sea water and foliar deposition) was done using non-specific analytical methods as methylene blue active substances (MBAS), leading to overestimation of the environmental concentrations of LAS. <p>The work hypothesis was that at actual environmental concentrations, the LAS does not play a key role in the foliar uptake of the sea salt deposited on the coastal vegetation by the marine aerosols, therefore the LAS may not be the main cause of the coastal forest decline. <p>The research involved both greenhouse experiments and field measurements. The experimental work was conducted on young Mediterranean trees (Laurus nobilis L. Quercus ilex L. and Pinus halepensis P. Mill.) and investigated the synergistic toxic effects of exposure to simulated marine aerosol contaminated with surfactants. An array of endpoints was used including photosynthetic activity, relative water content, foliar deposition and uptake of salt and LAS, and pigments analysis. The results of those experiments revealed that LAS itself did not have phytotoxic effects. Nevertheless, the surfactant was shown to enhance the foliar uptake of the salt in the tested species, especially in Pinus halepensis, confirming the conclusions of previous studies regarding the sensitivity of this species to polluted marine aerosols. <p>The field work was conducted in San Rossore National Park (Italy) and Porquerolles Island (France) and was focused on evaluating the health status of the Mediterranean forest (Quercus ilex L. Pinus halepensis Mill. and Pinus pinaster Aiton.) and also on quantification of LAS in coastal aerosols using highly specific analytical methods, like the mass spectrometry (MS). The frequencies and extent of injuries in the coastal trees were found to be correlated to the salt but not with the LAS content of the leaves. The concentrations of LAS in the Pinus and Quercus leaves were comparable in the two studied sites but the concentrations of salt were extremely high in San Rossore, suggesting that other factors may determine the excessive salt foliar uptake. The parallel MS and MBAS carried out in the same set of aerosol samples revealed that MBAS measurements were not relevant for LAS concentrations in the marine aerosols. Projecting the experimental results to the real LAS and salt exposure of the coastal forest, we concluded that LAS may play a marginal role in coastal vegetation decline. <p> / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

Na região do Vale do Ribeira, os resíduos de mineração foram dispostos diretamente sobre o solo, nas proximidades da empresa responsável pelo beneficiamento e fundição do minério de chumbo (Pb) (próximo à Vila Operária &#8211; município de Adrianópolis-PR). A escória de fundição enriquecida em metais potencialmente tóxicos (MPT), primeiramente foi disposta na forma de pilha. Em 2006, parte desta escória foi transferida para um aterro de resíduo sólido localizado a 50 m do antigo depósito e parte continuou no antigo local de disposição. As escórias que continuaram no antigo local foram espalhadas e cobertas com um solo residual. Esta cobertura não foi realizada de forma adequada, sendo que em algumas porções da área é possível ver as escórias, estando estas em contato direto com os animais (principalmente, ovinos e bovinos). Visando avaliar a influência da disposição das escórias na contaminação do solo de superfície e basal, foram coletadas amostras em distintas profundidades e em duas linhas de caminhamento principais (NS e EW) na área da antiga disposição. Nestas amostras foram realizadas caracterizações geotécnicas, geoquímicas e microbiológicas. Os ensaios realizados foram: granulometria conjunta, limites de Atterberg, capacidade de troca catiônica (CTC) e superfície específica (SE), matéria orgânica (MO), potencial hidrogeniônico (pH), potencial redox (Eh), condutividade elétrica (CE), delta pH (&Delta;pH), microscopia eletrônica de varredura com espectrômetro de energia dispersiva acoplado (MEV/EDS), mineralogia por difração de raios-x (DRX), fluorescência de raios-x (FRX), determinação da concentração pseudo-total (absorção atômica &#8211; AA; espectrometria de emissão atômica - ICP/AES), solubilização, lixiviação, extração sequencial, avaliação da comunidade microbiana por RCP-EEGD (ou PCR-DGGE) e sequenciamento do gene RNAr 16S via ILLUMINA. A avaliação da contaminação foi realizada considerando índice de geoacumulação (Igeo ), fator de enriquecimento (FE ou EF), Código de Avaliação de Risco (CAR ou RAC) e potencial de risco ecológico (Eir). O pH em H2O observado no depósito foi de 6,5 a 7,6, indicando que o meio é ligeiramente ácido. Já o Eh foi considerado oxidante. A CE foi especialmente elevada nas amostras superficiais (0-20 cm) e nos perfis coletados na linha de caminhamento EW. A CTC média foi de 14,3 cmolc/kg, sendo esta característica da caulinita. Quanto ao teor de matéria orgânica observou-se variação de 0,3 a 5,4 g/kg, sendo o valor médio de 2,14 g/kg. A base do depósito possui média de 68% de finos e índice de plasticidade de 2 a 35%. Para a base do depósito (de 60 a 100 cm) observou-se concentrações pseudo-totais de MPT bem inferiores ao topo. Em relação ao solo superficial observou-se elevada concentração pseudo-total, principalmente de Pb (média de 6.268,85 mg/kg) e Zn (média de 20.261,50 mg/kg). As concentrações de Cd observadas foram acima dos valores de background da área (média de 12,19 mg/kg). A concentração de MPT nas amostras coletadas na linha de caminhamento EW foram superiores às de NS, estando mais elevadas naquelas mais próximas à antiga empresa de beneficiamento. A partir dos ensaios de solubilização, lixiviação e extração sequencial, notou-se que o Pb e o Cd estão mais prontamente solúveis. Verificou-se para o Cd menor concentração pseudo-total, quando comparado com o Pb e Zn, todavia, observou-se para esse metal maior índice de geoacumulação, maior risco ecológico e maior mobilidade. A ordem obtida para os MPT, de acordo com o risco potencial, utilizando as frações mais móveis foi Cd > Pb &#8776; Zn. Obteve-se maior diversidade e riqueza bacteriana nas amostras com maior concentração pseudo-total de metais, maior Igeo e maior Eir . Nas amostras superficiais foram identificadas bactérias tolerantes a presença de MPT, como Rhodoplanes, Kaistobacter, Sphingomonas, Flavobacterium, Cellvibrio, Rheinhermera e Pseudomonas. Assim, conclui-se que a porção superficial do perfil e mais próxima a empresa que beneficiou o minério está mais contaminada e com maior risco que a basal. A partir desses resultados pode-se inferir que a integração de conhecimentos é fundamental na avaliação da contaminação em áreas de mineração. / In the Ribeira Valley region, mining wastes were placed directly on the soil near the company responsible for the processing and smelting of lead ore (Pb) (near of the Vila Operária &#8211; Adrianópolis-PR). The slag enriched in potentially toxic metals (PTM) was initially deposited in piles. In 2006 part of the slag was moved to a solid waste landfill located 50 m from the old deposit and part remained at the former disposal site. The slag that remained in the old deposit were spread out evenly and covered with a residual soil. This coverage was not performed adequately, and in some areas of the deposit the slag is on the soil surface, being in direct contact with animals (mainly sheep and cattle). In order to assess the contamination of slag disposal on soil, samples were collected at various depths and in two main transverse lines (NS and EW) in the area of the old deposit. Geotechnical, geochemical and microbiological characterization were performed in these samples. The assays carried out were: granulometry, Atterberg limits, cation exchange capacity (CEC) and specific surface (SS), organic matter (OM) content, hydrogenation potential (pH), redox potential (Eh), electrical conductivity (EC), delta pH (&Delta;pH), scanning electron microscopy coupled with energy dispersive spectrometer (SEM/EDS), mineralogy using X-ray diffraction (XRD), x-ray fluorescence (XRF), determination of pseudo-total concentration (atomic absorption - AA; inductively coupled plasma atomic emission spectroscopy - ICP/AES), solubilization, leaching, sequential extraction, microbial community evaluation by PCR-DGGE and sequencing of the 16S RNAr gene via ILLUMINA. The evaluation of the contamination was conducted using the geoaccumulation index (Igeo), enrichment factor (EF), Risk Assessment Code (RAC) and potential ecological risk (Eir). The mean pH in H2O observed in the deposit varied from 6.5 to 7.6 (slightly acid) and Eh was considered oxidant. EC was especially high in the surficial samples (0-20 cm) and in the profiles collected in the EW transverse line. The medium CEC was 14.3 cmolc/kg, characteristic of kaolinite. The organic matter content varied from 0.3 to 5.4 g/kg, with a mean value of 2.14 g/kg. The base of the deposit is constituted with a medium of 68% of fines and plasticity index of 2-35%. It was observed that the base of the deposit (60 to 100 cm) has a considerably lower pseudo-total concentration of PTM when compared to the topsoil. In the surficial soil it was observed high pseudo-total concentration, mainly Pb (mean of 6,268.85 mg/kg) and Zn (mean of 20,261.50 mg/kg). The Cd concentrations were above the background values of the area (mean of 12.19 mg/kg). The PTM concentration in samples collected in the EW transverse line were higher than those of NS, being specially higher in the samples closer to the former beneficiation company. According to the results obtained from the solubilization, leaching and sequential extraction assays, it was noted that Pb and Cd are more readily soluble. A lower pseudo-total concentration was observed for Cd, when compared to Pb and Zn, however, a higher geoaccumulation index, greater ecological risk and greater mobility was observed for this metal. The order for PTM, according to the potential risk, using the more mobile fractions was Cd > Pb &#8776; Zn. Greater diversity and bacterial richness were obtained in the samples with higher pseudo-total concentration of metals, higher Igeo and greater Eir. In the surficial samples, bacteria tolerant to the presence of PTM, such as Rhodoplanes, Kaistobacter, Sphingomonas, Flavobacterium, Cellvibrio, Rheinhermera and Pseudomonas were identified. Thus, it is concluded that the surface portion of the profile closer to the former smelting company is more contaminated and with greater risk than the basal portion. From the results it can be inferred that the integration of knowledge is fundamental in the evaluation of the contamination in mining areas.

Surfactants are used in a wide assortment of "down-the-drain" consumer products, yet they are often discharged in wastewater treatment plant effluent into receiving water, potentially causing environmental harm. The objective of this project was to predict surfactant toxic units and in-stream nutrients in the upper Trinity River watershed. Surface and pore water samples were collected in late summer 2005. General chemistries and surfactant toxic units were calculated. GIS models of anthropogenic and natural factors were collected and analyzed according to subwatersheds. Multiple regression analyses using the Maximum R2 improvement method were performed to predict surfactant toxic units and in-stream nutrients using GIS and in-stream values. Both geospatial and in-stream parameters generated multiple regression models for surfactant surface and pore water toxic units, as well as in-stream nutrients, with high R2 values. Thus, GIS and in-stream parameter modeling have the potential to be reliable and inexpensive method of predicting surfactant toxic units and nutrient loading in the upper Trinity River watershed.

In response to the dearth of research focusing solely on immigrant fathers, we propose the Integrative Conceptual Model to investigate the psychological well-being of recent immigrant fathers from East Asia to the United States. This model addresses how multiple factors in the society (e.g., policy), work and community (e.g., employment), family (e.g., father-child and couple relationships), and individual (e.g., education) levels in the host and home countries are linked to East Asian immigrant fathers’ adaptation to their new environment. More specifically, we focus on the unique risk factors and protective factors to their adjustment, which are vital to the psychological well-being of recent immigrant fathers from East Asia. The Integrative Conceptual Model contributes to the limited fatherhood literature to help understand the multifaceted nature of immigrant fatherhood. Implications include creating culturally sensitive education and intervention programs for East Asian immigrant fathers.

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.

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.

Submitted by Biblioteca de Pós-Graduação em Geoquímica BGQ (bgq@ndc.uff.br) on 2017-03-13T16:00:43Z No. of bitstreams: 1 Carvalheira 2012_final2.pdf: 2519362 bytes, checksum: 35cd719bc898e8695473b92b7516849d (MD5) / Made available in DSpace on 2017-03-13T16:00:43Z (GMT). No. of bitstreams: 1 Carvalheira 2012_final2.pdf: 2519362 bytes, checksum: 35cd719bc898e8695473b92b7516849d (MD5) / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geociências- Geoquímica, Niterói, RJ. / O objetivo geral deste trabalho foi a realização do prognóstico do comportamento do mercúrio após a implantação do Programa de Despoluição da Baía de Guanabara (PDBG), a partir das relações entre a contaminação dos sedimentos e o nível de degradação do meio, para avaliação da sustentabilidade do multiuso deste sistema, em relação ao recurso pesqueiro, dependente da biodisponibilidade e acumulação deste metal em tecido de peixes. Para tal foi adequado e calculado o índice de risco ecológico potencial (IREP) para o cenário atual e para cenário a médio prazo (2020), bem como um modelo de incorporação de mercúrio por peixes. A bioacumulação e a biomagnificação foram avaliadas para o cenário atual, incluindo a definição dos níveis tróficos ocupados pelas espécies de peixes estudadas através do uso de isótopos estáveis de carbono e nitrogênio. Todos os setores apresentaram grau de contaminação considerado muito alto, demonstrando que há contaminação dos sedimentos superficiais por As, Cd, Cr, Cu, Hg, Pb e Zn. Pelo IREP pode-se observar que 3 setores da baía possuem risco ecológico potencial moderado (Central, Leste e Noroeste) e os outros 3 (Enseadas, Nordeste e Oeste), riscos baixos, para o cenário atual. Para 2020, esses riscos não foram alterados significativamente, mas apresentaram tendência de aumento, similarmente a tendência encontrada para as concentrações de mercúrio em peixes a partir da modelagem. No cenário atual as concentrações de mercúrio em peixes são baixas, mesmo nas espécies carnívoras (abaixo de 200ng/g). Os níveis tróficos calculados com base na razão isotópica de nitrogênio foram: Cynoscion sp. = 4,3; Micropogonias furnieri = 2,7; Mugil sp. = 2,4; e, Genidens genidens = 2,4. O processo biogeoquímico de biomagnificação do mercúrio pode ser observado utilizando 3 dessas 4 espécies (Cynoscion sp., Micropogonias furnieri, Mugil sp.). A espécie de bagre Genidens genidens por seu forrageamento ser diferenciado, a acumulação do mercúrio parece ser mais eficiente, apesar do nível trófico ocupado ser igual ao da tainha Mugil sp.. O fator de biomagnificação entre carnívoro/herbívoro foi igual a 4. Os resultados demonstraram que há ocorrência da biomagnificação trófica na baía. E através dos modelos utilizados, apesar da melhora na qualidade da água, o risco associado a exposição a metais presentes nos sedimentos continuará similar ou aumentará após atingir as metas de médio prazo do PDBG. / The aim of this study was to perform a prognostic of the behavior of mercury with the implementation of the decontamination program of Guanabara Bay (BGPD), from the relationships between metal contamination of sediments and degradation level of the system, as a way to assess the sustainability of the multiple uses of this bay, especially the fishery resources, which is dependent of bioavailability and accumulation of metals, including mercury, in fish tissue. For this purpose, the potential ecological risk index (PERI) was adequate and calculated for the actual scenario and for a medium term scenario (2020), and also a model of mercury incorporation by fish. Bioaccumulation and biomgnification of mercury were also evaluated for the actual scenario, including the definition of the trophic levels occupied by fish species, using stable isotopes of carbon and nitrogen. All the sectors of Guanabara Bay presented very high contamination degree, confirming that there is contamination of superficial sediments for As, Cd, Cr, Cu, Hg, Pb and Zn. PERI classified three sectors of the bay as moderate risk (Central, East and Northwest) and the other three (Coves, Northeast and West) as low risk at the actual scenario. For 2020, these risks have not changed significantly, but tended to increase, what occurred also for the results from modeling mercury concentrations in fish. In the actual scenario mercury concentrations in fish are low, even in carnivorous species (lower than 200ng/g). The trophic level obtained using stable isotopes of nitrogen were: Cynoscion sp. = 4.3; Micropogonias furnieri = 2.7; Mugil sp. = 2.4; e, Genidens genidens = 2.4. The biogeochemical process of biomagnification of mercury can be observed using three species among the four studied species (Cynoscion sp., Micropogonias furnieri, Mugil sp.). Although Mugil sp. and the catfish Genidens genidens belongs to similar trophic level, the catfish seemed to accumulate mercury more efficiently, probably because of its benthic foraging. The biomagnifications factor among carnivorous/herbivorous was 4. The results demonstrated that the biomagnification occurs in this bay. And also, they showed that despite the improvement in water quality, the risk associated with exposure to metals present in sediments continue at the same level, or even increase, after reaching the goals of medium-term of the BGPD.

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