Interest in the presence of environmental contaminants in the Canadian arctic and sub-arctic arises in part over concerns that Aboriginal people residing in these regions continue to rely on subsistence harvesting. Organochlorines (OCs) are a type of persistent organic pollutant (POP) that have a unique chlorine-carbon bond; this bond facilitates their unprecedented environmental longevity, lipophilicity and hydrophobic nature. OCs have been found in both the biotic and non-biotic compartments of northern ecosystems. This study examined patterns of differences with respect to body burden of organochlorines (lipid-adjusted) between the residents of the Ontario First Nations of Fort Albany (the site of MCRL Site 050), Kashechewan (no radar site), and Peawanuck (the site of MCRL 500) to assess whether geo-proximity to abandoned radar sites influenced organochlorine body burden with respect to the people of Fort Albany and Peawanuck. Correspondence analysis (CA-1) revealed people from Fort Albany had relatively higher pesticide concentrations (β-HCH and DDT, but not Mirex) and relatively lower CB (156 and 170) body burdens when compared to participants from Kashechewan and Peawanuck. CA- 2 revealed Peawanuck residents had relatively higher concentrations of CB180, DDE and hexachlorobenzene and relatively lower levels of DDT and mirex compared to participants from Kashechewan and Fort Albany. Results are suggestive but not conclusive that MCRL Site 500 may have influenced body burdens of Peawanuck residents.

Interest in the presence of environmental contaminants in the Canadian arctic and sub-arctic arises in part over concerns that Aboriginal people residing in these regions continue to rely on subsistence harvesting. Organochlorines (OCs) are a type of persistent organic pollutant (POP) that have a unique chlorine-carbon bond; this bond facilitates their unprecedented environmental longevity, lipophilicity and hydrophobic nature. OCs have been found in both the biotic and non-biotic compartments of northern ecosystems. This study examined patterns of differences with respect to body burden of organochlorines (lipid-adjusted) between the residents of the Ontario First Nations of Fort Albany (the site of MCRL Site 050), Kashechewan (no radar site), and Peawanuck (the site of MCRL 500) to assess whether geo-proximity to abandoned radar sites influenced organochlorine body burden with respect to the people of Fort Albany and Peawanuck. Correspondence analysis (CA-1) revealed people from Fort Albany had relatively higher pesticide concentrations (β-HCH and DDT, but not Mirex) and relatively lower CB (156 and 170) body burdens when compared to participants from Kashechewan and Peawanuck. CA- 2 revealed Peawanuck residents had relatively higher concentrations of CB180, DDE and hexachlorobenzene and relatively lower levels of DDT and mirex compared to participants from Kashechewan and Fort Albany. Results are suggestive but not conclusive that MCRL Site 500 may have influenced body burdens of Peawanuck residents.

Objectives: To investigate factors influencing consumption of traditional foods (e.g., wild game, fish) and concerns about environmental contaminants among schoolchildren of the Mushkegowuk Territory First Nations (Moose Factory, Fort Albany, Kashechewan, Attawapiskat, and Peawanuck). Study Design: Cross-sectional data collection from a Web-based Eating Behaviour Questionnaire (WEB-Q). Methods: Schoolchildren in grades 6-12 (n = 262) responded to four of the WEB-Q questions: (1) Do you eat game? (2) How often do you eat game? (3) How concerned are you about the environmental contaminants in the wild game and fish that you eat? (4) I would eat more game if...[ six response options]. Data were collected from 2004-2009. Hierarchical log-linear modelling (LLM) was used for analyses of multi-way frequency data. Results: Of the school children answering the specific questions: 174 consumed game; 95 reported concerns about contaminants in game; and 84 would increase their game consumption if it were more available in their homes. LLM revealed significant differences between communities; schoolchildren in Moose Factory consumed game ???rarely or never??? at greater than expected frequency, and fewer than expected consumed game ???at least once a day.??? Schoolchildren in Kashechewan had greater frequency of daily game consumption and few were concerned about contaminants in game. Using LLM, we found that sex was an insignificant variable and did not affect game consumption frequency or environmental contaminant concern. Conclusion: The decreasing importance of the traditional diet was most evident in Moose Factory, possibly due to its more southerly location relative to the other First Nations examined.

Periodic monitoring of contaminant levels in fish from the Yukon Territory indicated that organochlorine (OC) contaminants had rapidly declined since the early 1990s. This study examined OC concentrations, including chlordane (sigma-CHL), sigma-DDT, hexachlorocyclohexane (sigma-HCH), toxaphene (sigma-CHB), sigma-PCB and chlorinated benzenes (sigma-CBz) in sentinel fish (species of consistent annual observation and collection) from two Yukon lakes (Kusawa, Quiet), and from the aquatic food web of a focus lake (Lake Laberge) across several temporal points between 1993 and 2003. OC analysis and phytoplankton counts from dated sediment cores as well as climate data were also collected. Population, morphological (length, weight, age), biochemical (lipid content, delta-13C, delta-15N) and OC contaminant data for fish and invertebrates (zooplankton, snails, clams) were reviewed to elucidate the primary causes for these OC declines. Although some spatial differences in contaminant levels exist between the Yukon lakes, OC concentrations were declining for lake trout in all three lakes, with declines also noted for burbot from Lake Laberge. Several other fish species as well as zooplankton from Lake Laberge exhibited decreases in contaminant levels except northern pike, which registered consistently higher levels from 1993 to 2001. There was no evidence to support the hypotheses of changes in fish trophic levels or food sources with the exception of burbot, which marginally decreased, and northern pike, which climbed a half trophic level. Through OC flux analysis in dated sediments, the hypothesis that declines in abiotic deposition affected the contaminant levels in the food web was also negated. The closure of the Lake Laberge commercial fishery resulted in faster fish growth and larger fish populations, which are contributing to biomass dilution of OC concentrations, higher OC biomagnification factors for some species and likely changes in predator-prey interactions as resource competition increases. The large ratio of OC decreases in the lower vs. higher trophic levels of Lake Laberge have increased food web magnification factors (FWMF) for all six OC groups. It is also suspected that above-average temperatures and below-average precipitation in the lower Yukon region over the 1990s may have contributed towards an increase in lake primary production resulting in biomass dilution of contaminants in zooplankton for all three study lakes. Concurrently, shifts in the Lake Laberge zooplankton community, from climate fluctuations or increased fish predation, have gone from an abundance of Cyclops scutifer in 1993 to dominance by Diaptomus pribilofensis in 2001, although sample sites were limited. Characteristics specific to each species (e.g. body size, composition and metabolism) likely play a role in the significant OC declines measured in zooplankton. Fluctuations in population dynamics, species characteristics and OC contaminant concentrations in the Lake Laberge ecosystem may continue for several years to come. Sentinel species such as lake trout, burbot, whitefish, cisco and plankton should continue to be monitored in all three Yukon lakes for future temporal correlations with contaminants or climate change.

Periodic monitoring of contaminant levels in fish from the Yukon Territory indicated that organochlorine (OC) contaminants had rapidly declined since the early 1990s. This study examined OC concentrations, including chlordane (sigma-CHL), sigma-DDT, hexachlorocyclohexane (sigma-HCH), toxaphene (sigma-CHB), sigma-PCB and chlorinated benzenes (sigma-CBz) in sentinel fish (species of consistent annual observation and collection) from two Yukon lakes (Kusawa, Quiet), and from the aquatic food web of a focus lake (Lake Laberge) across several temporal points between 1993 and 2003. OC analysis and phytoplankton counts from dated sediment cores as well as climate data were also collected. Population, morphological (length, weight, age), biochemical (lipid content, delta-13C, delta-15N) and OC contaminant data for fish and invertebrates (zooplankton, snails, clams) were reviewed to elucidate the primary causes for these OC declines. Although some spatial differences in contaminant levels exist between the Yukon lakes, OC concentrations were declining for lake trout in all three lakes, with declines also noted for burbot from Lake Laberge. Several other fish species as well as zooplankton from Lake Laberge exhibited decreases in contaminant levels except northern pike, which registered consistently higher levels from 1993 to 2001. There was no evidence to support the hypotheses of changes in fish trophic levels or food sources with the exception of burbot, which marginally decreased, and northern pike, which climbed a half trophic level. Through OC flux analysis in dated sediments, the hypothesis that declines in abiotic deposition affected the contaminant levels in the food web was also negated. The closure of the Lake Laberge commercial fishery resulted in faster fish growth and larger fish populations, which are contributing to biomass dilution of OC concentrations, higher OC biomagnification factors for some species and likely changes in predator-prey interactions as resource competition increases. The large ratio of OC decreases in the lower vs. higher trophic levels of Lake Laberge have increased food web magnification factors (FWMF) for all six OC groups. It is also suspected that above-average temperatures and below-average precipitation in the lower Yukon region over the 1990s may have contributed towards an increase in lake primary production resulting in biomass dilution of contaminants in zooplankton for all three study lakes. Concurrently, shifts in the Lake Laberge zooplankton community, from climate fluctuations or increased fish predation, have gone from an abundance of Cyclops scutifer in 1993 to dominance by Diaptomus pribilofensis in 2001, although sample sites were limited. Characteristics specific to each species (e.g. body size, composition and metabolism) likely play a role in the significant OC declines measured in zooplankton. Fluctuations in population dynamics, species characteristics and OC contaminant concentrations in the Lake Laberge ecosystem may continue for several years to come. Sentinel species such as lake trout, burbot, whitefish, cisco and plankton should continue to be monitored in all three Yukon lakes for future temporal correlations with contaminants or climate change.

An alarming reduction in the numbers of several species of seals in the Baltic Sea was observed during the second half of the 1900s. Organochlorines, particularly PCBs, were found to cause the decline, inducing sterility and severe bone loss. If bone tissue is affected by PCBs, bone could be used as a biomarker for exposure to environmental contaminants. To isolate the effects of PCBs from other factors, experimental studies have been conducted on model species, such as mink. In this study, 58 mink femurs from three different treatment groups and one control group were analysed. Altogether 14 different parameters were measured using peripheral quantitative computed tomography (pQCT). Mink treated with a low dose of PCBs develop increased content, area and thickness of cortical bone. Mink treated with a high dose of PCBs do not show the same effects but have a cortical area similar to that of non-exposed animals. The trabecular density and content is increased in all groups that have been exposed to PCBs. The observed effects may be the result of dioxin-like PCBs binding to the aryl hydrocarbon receptor (AhR). The activation of AhR leads to disruptions in endocrine systems, that in turn impacts bone modelling and remodelling. However, other pathways cannot be ruled out, including the effects of non-dioxin-like PCBs. Further analyses are needed in order to fully understand how PCBs affect bone tissue properties.

Made available in DSpace on 2016-08-17T18:39:41Z (GMT). No. of bitstreams: 1 3999.pdf: 1632042 bytes, checksum: b8e3d99058c0785179cfeb15eabf0dc9 (MD5) Previous issue date: 2010-11-18 / The use of pesticides for the purpose of improving agricultural productivity during the last century, played a key role in environmental contamination especially in surface water and sediment. Pesticides used on a large scale are the organochlorines, which, once present in the soil can be transported in large quantities by the rain, mainly reaching surface water. This study aimed to evaluate the contamination of water in the River Basin Monjolinho mutirressíduos by organochlorine pesticides, through physical, chemical, and also using gas chromatography with electron capture detector (GC / ECD) for detection of organochlorine compounds . Therefore, we sampled water and sediment at five points along the River Basin Monjolinho. The method presented achieved Imitating of detection (LOD) of 0.0039 to 0.86 mg L-1, limit of quantification (LOQ) of 0.07 to 2.59 mg L-1 and determination coefficient of 0.99. Through the results of chromatographic analysis, physico-chemical water and sediment, we found the presence of organochlorine compounds in all sampling points, a fact which may be related to persistent use of these compounds near the basin. These results support the view that the organochlorine pesticides are still part of the products used in agriculture of our country and also that the proposed methodology for the determination of organochlorine compounds multiressíduos is profitable and satisfactory. / A utilização de pesticidas com a finalidade de melhorar a produtividade agrícola, durante o ultimo século, teve papel fundamental na contaminação ambiental sobretudo em água superficiais e sedimento. Dos pesticidas usados em grande escala, encontramse os organoclorados, os quais, uma vez presentes no solo podem ser transportados em grandes quantidades, pelas águas das chuvas, atingindo principalmente, águas superficiais. O presente trabalho teve como objetivo avaliar a contaminação de água na Bacia do Rio do Monjolinho por mutirressíduos de pesticidas organoclorados, através de análises físicas, químicas e também utilizando cromatografia gasosa com detector de captura de elétrons (GC/ECD) para detecção de compostos organoclorados. Para tanto foram realizadas coletas de água e sedimento em cinco pontos ao longo da Bacia do Rio do Monjolinho. O método apresentado obteve lmite de detecção (LD) de 0,0039 à 0,86 Pg L-1 , limite de quantificação (LQ) de 0,07 à 2,59 Pg L-1 e coeficiente de determinação de 0,99. Através dos resultados obtidos das análises cromatográficas, parâmetros físico químicos de água e sedimento, constatou-se a presença de compostos organoclorados em todos os pontos coletados, fato o qual pode estar relacionado ao uso persistente destes compostos próximos a bacia. Estes resultados permitem considerar que aos pesticidas organoclorados ainda fazem parte dos produtos utilizados na agricultura de nosso país e, também, que a metodologia proposta para a determinação de multiressíduos de compostos organoclorados é proveitosa e satisfatória.

Os compostos organoclorados causam grande impacto na natureza devido a três características básicas: persistência ambiental, bioacumulação e alta toxicidade. Os mamíferos marinhos estão entre os organismos mais vulneráveis à toxicidade crônica desses contaminantes porque, além de concentrá-los em grande quantidade, a fêmea transfere parte de sua carga ao filhote durante a gestação e a lactação. Assim, o presente trabalho teve como objetivos otimizar uma metodologia para determinação de organoclorados (pesticidas e PCBs) em matrizes gordurosas e verificar a ocorrência dos mesmos na gordura subcutânea de mamíferos marinhos amostrados na costa de São Paulo (Brasil) e na Ilha Rei George (Antártica). No protocolo metodológico otimizado, a extração foi realizada em extrator Soxhlet (8 h) com uma mistura de n-hexano e diclorometano. A etapa de purificação foi feita através de tratamento ácido e o extrato final analisado em cromatógrafo a gás equipado com detector de captura de elétrons (GC-ECD). A performance do método foi avaliada com material de referência certificado, enquadrando-se dentro de padrões internacionais de controle de qualidade. O limite de detecção do método foi em média 2 ng g-1. As análises apontaram DDTs e PCBs como os grupos que mais causam impacto nos cetáceos da costa de São Paulo. Isso refletiu o histórico de ambos no Brasil, tanto em indústria como em agricultura e saúde pública. Em contrapartida, HCHs e HCB não apresentaram concentrações elevadas, fato que pode ser atribuído à volatilidade dos mesmos em regiões de clima tropical. Da mesma maneira, a-clordano, g-clordano e mirex não foram detectados em níveis significativos. A foca de Weddell (Leptonychotes weddelli), habitante do continente antártico, evidenciou as menores cargas de contaminante entre os animais estudados. As toninhas (Pontoporia blainvillei) e o golfinho-nariz-de-garrafa (Tursiops truncatus) também apresentaram baixos níveis de organoclorados. Os botos-cinza (Sotalia fluviatilis) revelaram concentrações de DDT iguais ou superiores a cetáceos da Índia, país onde esse pesticida ainda não está proibido. Já o golfinho-de-dentes-rugosos (Steno bredanensis) mostrou a maior contaminação entre os animais analisados, comparável a espécies estudadas em águas costeiras de países desenvolvidos (onde os organoclorados foram muito utilizados). / Organochlorine compounds cause strong impact on the nature, as a consequence of three basic characteristics: environmental persistence, bioaccumulation, and high toxicity. The marine mammals are one of the most vulnerable organisms to the chronic toxicity of these contaminants. Besides the high concentration in the body, the female transfers part of her load to the offspring during gestation and lactation. The aim of this study was (1) the optimization of a methodology for determining chlorinated hydrocarbons (pesticides and PCBs) in fatty biological matrices and (2) the analysis of organochlorines in marine mammals blubber sampled along São Paulo coast (Brazil) and King George Island (Antarctica). According to the optimized methodology, the extraction was carried out in Soxhlet apparatus (8 h) with a mixture of n-hexane and dichloromethane. The clean-up was carried out with acid treatment and the resulting extract injected into gas chromatography coupled to electron capture detector (GC-ECD). The method performance was evaluated with certified reference material and fitted for international standards of control quality. The mean method detection limit was 2 ng g-1. DDTs and PCBs were the most concentrated organochlorines in the cetaceans from São Paulo coast. These findings reflected their past usage in Brazil by industry, agriculture, and public health. On the other hand, both HCHs and HCB were not found in high concentration likely due to their volatility in tropical climate areas. Mirex, a-chlordane and g-chlordane were not detected in elevated levels. The Weddell seal (Leptonychotes weddelli), from Antarctic continent, presented the smallest load among the studied animals. As the same way, the franciscanas (Pontoporia blainvillei) and the bottlenose dolphin (Tursiops truncatus) presented low organochlorine levels. The marine tucuxi (Sotalia fluviatilis) showed equal or higher DDT concentration than Indian cetaceans where that pesticide is still in use. The rough-toothed dolphin (Steno bredanensis) revealed the greatest contamination among the analyzed animals, comparable to species studied in the coastal waters of developed countries (where organochlorines were extensively used).

A necessidade de produção de papel por processo ambientalmente corretos é um grande desafio. A polpa celulósica branqueada gera um dos efluentes mais problemáticos e estudados atualmente. O tipo de efluente na planta de branqueamento é mais importante que a quantidade gerada. O efeito da DBO no corpo receptor desse resíduo não é o principal problema, o problema está na geração dos compostos organoclorados, que estão dissolvidos nesse efluente. Muitas substâncias desse grupo são tóxicas e também podem ter efeitos carcinogênicos e mutagênicos. O estudo desse tipo de efluente em sistemas de tratamento biológico é de extrema importância e é tema de diversos trabalhos científicos. Entretanto, há algumas dificuldades relacionadas com a viabilidade de composição, a obtenção, o manuseio e o armazenamento de amostras desse tipo de efluente em laboratórios de pesquisa. O objetivo desse trabalho foi, portanto, obter um efluente sintético em escala laboratorial, sob condições controladas, que pudesse simular o comportamento de um efluente gerado em uma planta de branqueamento, quando em um sistema de tratamento biológico. Para isso, partiu-se de uma amostra de polpa celulósica não-branqueada e realizou-se a etapa de branqueamento no laboratório sob condições semelhantes às industriais, obtendo-se assim, o efluente desejado, que foi chamado de Efluente Sintético. A comparação foi realizada através da caracterização físico-química deste efluente e de um efluente de uma planta industrial de branqueamento, chamado de Efluente Industrial. Reatores anaeróbios operando em batelada foram utilizados para avaliação do comportamento destes influentes de tratamento biológico. Observou-se que o comportamentos de ambos os efluentes pôde ser considerado semelhante. A avaliação foi feita através do acompanhamento da produção de gás metano e eficiências de remoção de DQO e AOX. / The necessity of producing paper by environmental friendly processes is a big challenge; bleached cellulose pulp produces one of the most problematic and studied kind of effluent nowadays. The kind of effluent produced in the bleaching mill is more important than the quantity of this effluent. The effect of the BOD of this effluent in the receiving water is not the main problem, the problem is on the generation of organochlorines compounds that are dissolved in this effluent. A lot of substances of this group are toxic and can show carcinogenic and mutagenic effects. The study of effluent in biologic systems of treatment is extremely important and is theme of a variety of scientific works. However, there are some difficulties related to the variability of composition, the obtainment, the handling and the storage of samples of this kind of effluent in a research laboratory. Therefore, the purpose of this work was to obtain a synthetic effluent in a laboratory scale, under controlled conditions, that could simulate the behavior of an effluent produced in a bleaching mill, when in a biological system of treatment. For this, it was used a sample of a unbleached cellulose pulp and it was done the stage of bleaching in the laboratory under similar conditions to the mill\'s, obtaining in this way the desired effluent, that was called Synthetic Effluent. It was done a comparison between this effluent and a bleaching mill effluent, that was called Industrial Effluent, by a physical and chemical characterization. It was used anaerobic batch reactors to make a evaluation of the behavior of these effluents in a biological system of treatment. It was observed that the behavior of both effluents can be considered similar. The evaluation was done by the observation of methane gas production and by the efficiencies of COD and AOX removal.

Increasing awareness about the presence and ecological ramifications of toxic, persistent and bioaccumulative contaminants within the Great Lakes system spurred the implementation of numerous bans and emissions restrictions over the past few decades. Due to their high trophic status in food webs and the critical link they serve with human consumers, fish species have historically been monitored to assess the relative success of such remedial efforts within the region and to simultaneously ascertain the current risks posed to local humans. Using Bayesian dynamic linear modelling, this project first aimed to evaluate temporal trends of various organochlorine contaminants within Lake Erie fish communities, the results of which generally indicated decreasing trends through time. The second half of this study used a similar Bayesian approach to propose a framework for updating fish consumption advisories, with specific attention paid to the acknowledgment of uncertainty and natural variability when producing such consumption guidelines.