The persistent organic pollutants (POPs) refer to many different chemicals that, upon release into the environment, remain intact for several decades. These contaminants travel long distances through repeated cycles of deposition and evaporation, and eventually deposit in the Arctic regions. The purpose of this work was to examine the potential human health implications of POP exposures among the Canadian Inuit, using modelling and epidemiological approaches. Blood guideline values were developed for the organochlorine pesticides, chlordane and toxaphene, and the polychlorinated biphenyls (PCBs) using the concept of biomonitoring equivalents (BEs), which are based on toxicity endpoints and toxicokinetic modelling to convert an oral reference dose to an equivalent blood concentration. The biomonitoring data from the Adult Inuit Health Survey (2007-2008) and the Canadian Health Measures Survey (CHMS, Cycle 1 2007-2009) were compared with the derived guideline values to assess population-level risks of exposures for the Inuit and the general Canadian population, respectively. Epidemiological analyses were also conducted to explore if POPs were associated with diabetes and high cholesterol, using data from the Inuit Health Survey. A set of BE values were derived for chlordane isomers and metabolite, three abundant toxaphene isomers, and the PCBs. The derived values are in a similar range of the BEs of other POPs in the literature. Among the Inuit, a large percentage exceeded the trans-nonachlor guideline value, particularly among the elderly. Fewer exceedances were observed for cis-nonachlor and oxychlordane, none for toxaphene, and minimally for the PCBs. In comparison, no exceedances for any of the POPs were observed in the general Canadian population. Highest vs. lowest quartile exposures to PCBs and p,p’-DDE were associated with increased risk of diabetes and an increase in fasting glucose among the Inuit. In addition, PCBs were associated with increased risk of high cholesterol, and higher levels of serum triglycerides, total cholesterol, and low-density lipoprotein cholesterol (LDL-C), but not high-density lipoprotein cholesterol (HDL-C). The results of this work suggest that exposures to POPs remain a potential health concern among the Canadian Inuit. Future research efforts should be devoted to collecting updated contaminant concentrations for the Inuit, measuring contaminants in prepared food samples, conducting cohort studies on contaminant exposures and health outcomes, and assessing the effects of chemical mixtures using statistical approaches and toxicokinetic modelling.

Chemical species carry information in two dimensions, in their concentrations and their isotopic signatures. The concentrations of metabolites or synthetic compounds describe the composition of a chemical or biological system, while isotopic signatures describe processes in the system by their reaction pathways, regulation, and responses to external stimuli. Stable isotopes are unique tracers of these processes because their natural abundances are modulated by isotope effects occurring in physical processes as well as in chemical reactions. Nuclear magnetic resonance (NMR) spectroscopy is a prime technique not only for identification and quantification of small molecules in complex systems but also for measuring intramolecular distribution of stable isotopes in metabolites and other small molecules. In this thesis, we use quantitative NMR in three fields: in food science, environmental pollutant tracing, and plant-climate science. The phospholipid (PL) composition of food samples is of high interest because of their nutritional value and technological properties. However, the analysis of PLs is difficult as they constitute only a small fraction of the total lipid contents in foods. Here, we developed a method to identify PLs and determine their composition in food samples, by combining a liquid-liquid extraction approach for enriching PLs, with specialized 31P,1H-COSY NMR experiments to identify and quantify PLs. Wide-spread pollution with synthetic compounds threatens the environment and human health. However, the fate of pollutants in the environment is often poorly understood. Using quantitative deuterium NMR spectroscopy, we showed for the nitrosamine NDMA and the pesticide DDT how intramolecular distributions (isotopomer patterns) of the heavy hydrogen isotope deuterium reveal mechanistic insight into transformation pathways of pollutants and organic compounds in general. Intramolecular isotope distributions can be used to trace a pollutant’s origin, to understand its environmental transformation pathways and to evaluate remediation approaches. The atmospheric CO2 concentration ([CO2]) is currently rising at an unprecedented rate and plant responses to this increase in [CO2] influence the global carbon cycle and will determine future plant productivity. To investigate long-term plant responses, we developed a method to elucidate metabolic fluxes from intramolecular deuterium distributions of metabolites that can be extracted from historic plant material. We show that the intramolecular deuterium distribution of plant glucose depends on growth [CO2] and reflects the magnitude of photorespiration, an important side reaction of photosynthesis. In historic plant samples, we observe that photorespiration decreased in annual crop plants and natural vegetation over the past century, with no observable acclimation, implying that photosynthesis increased. In tree-ring samples from all continents covering the past 60 – 700 years, we detected a significantly smaller decrease in photorespiration than expected. We conclude that the expected “CO2 fertilization” has occurred but was significantly less pronounced in trees, due to opposing effects. The presented applications show that intramolecular isotope distributions not only provide information about the origin and turnover of compounds but also about metabolic regulation. By extracting isotope distributions from archives of plant material, metabolic information can be obtained retrospectively, which allows studies over decades to millennia, timescales that are inaccessible with manipulation experiments.

Many of the factors that shape contaminant accumulation profiles in marine mammals also strongly influence fat soluble vitamin accumulation. Vitamin A and E are essential fat soluble nutrients for numerous biological processes, including reproduction, growth, endocrine and immune function. Contaminants, such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), can alter vitamin dynamics; as such these vitamins have been proposed as sensitive biomarkers of contaminant exposure in wildlife. In light of these considerations, the present thesis was aimed at better understanding the factors that influence the accumulation of lipophilic contaminants and vitamins in western Arctic beluga whales, and to determine if there was an interaction between the two. Maternal offloading to neonates during gestation reduced overall contaminant (PCBs and PBDEs) and vitamin (A and E) concentrations in reproductively active female whales. The PCB and PBDE congener pattern in mothers changed during gestation as a result of preferential transfer of light-low Log KOW congeners to the fetus. Overall, female beluga whales transferred approximately 11% of their PCB and PBDE blubber burden to their fetus. In terms of vitamins transfer, lower concentrations of tocopherols, retinol and retinyl esters were found in reproductively active females relative to males and reproductively inactive females. Metabolism was also found to be an important factor for contaminant and vitamin accumulation in beluga tissues. In a principal components analysis, PCBs clustered into metabolically-derived structure-activity groups, which separated along the first principal component according to its metabolic potential (metabolizable vs. recalcitrant). Contaminant-related up-regulation of metabolizing enzymes, including cytochrome P450, likely explained changes in the concentration and pattern of PCB and PBDE congeners, as well as hepatic, plasma, and blubber vitamin A and E. Since vitamins and lipophilic contaminants accumulated in beluga whales in the same way in relation to most biological processes, including sex, reproduction, size, condition, and feeding ecology, it was important to control and reduce the number of these confounding factors before claiming any tissue vitamin change was indeed the result of chemical exposure. In doing so, it was found that vitamin A and E homeostasis was influenced by PCBs in beluga whales, resulting in reduced hepatic storage and increased plasma and blubber concentrations. Overall, these results suggest that liver, plasma, and inner blubber vitamin A and E concentrations can be sensitive biomarkers of contaminant exposure only if major confounding effects are taken into consideration. The implications of altered vitamin dynamics on the health of beluga whales is unknown at this time; however, as Arctic marine mammals face continued stress related to climate change, increased human disturbance and emergence of infectious diseases, this study can serve as essential baseline data that can be used to monitor the health status of western Arctic beluga whales. / Graduate / 0383 / 0329 / 0768 / jpdesforges@gmail.com

Seafood represents the most important source of long-chain polyunsaturated fatty acids (LC-PUFAs) in the human diet. However, consuming fish can present risks from persistent organic pollutants (POPs) that bioaccumulate in edible tissues following dietary exposure. In farmed fish, POPs accumulate as a result of feeding diets based on fish oil (FO). Fish oil substitution can reduce POP accumulation, but also results in loss of beneficial LC-PUFAs. Fish oil-based finishing diets at the end of production can restore LC-PUFAs, but this strategy also increases POPs. The present study assessed the use of saturated fatty acid (SFA)-rich lipids to replace fish oil in grow-out feeds in conjunction with a fish oil-rich finishing diet to determine if this strategy could produce hybrid striped bass with equal production performance, equivalent LC-PUFA levels, and reduced POP concentrations. Triplicate tanks of hybrid striped bass were raised on diets containing fish oil (100% FO), fish oil spiked with additional POPs (100% FO Spike), or blends (50/50 or 25/75) of FO and coconut (CO) or palm (PO) oils (50% CO, 50% PO, 75% CO, 75% PO) with and without an eight week finishing period with the 100% FO diet prior to harvest. Production performance, fillet LC-PUFA, and POP content were assessed. Production performance was not adversely affected by any of the feeding regimens. However, fatty acid profile was altered, with fillets of fish consuming less fish oil having lower LC-PUFA and POP levels. Finishing yielded a modest increase in fillet LC-PUFAs and POPs, but POPs accumulated more readily than LC-PUFAs during finishing. However, harvest fillet POP and LC-PUFA levels in the experimental groups were lower relative to levels in the 100% FO group. Replacing fish oil in aquafeeds can produce fish with reduced LC-PUFAs, and also reduced POPs. Feeding fish oil results in more rapid accumulation of POPs than LC-PUFA. Overall, the 75% fish oil replacement feeds yielded fish with the highest ratio of LC-PUFAs to POPs. Despite lower LC-PUFA content, fillets of fish fed the 75% fish oil replacement feeds could be incorporated into a weekly meal plan with other dietary sources of LC-PUFAs to meet dietary recommendations for these essential nutrients.

Permafrost thaw slumping along lakeshores in lakes of the Mackenzie Delta Uplands, NT is known to alter water chemistry significantly. Its impact on benthic communities and persistent organic pollutant (POP) behaviour in lakes is not known. Benthic invertebrate communities responded to slumps through changes to community composition and size spectra. Larger taxa tended to dominate in lakes with slumps. Variability in biomass size spectra was related to total dissolved nitrogen concentration and slump size. Concentrations of POPs in Gammarus were negatively correlated with total phosphorus and positively correlated with the percentage of the catchment slumped. Lakes with slumps generally had higher mean concentrations of POPs in Gammarus (ex. ΣPCBsDisturbed = 27.54 ng/g lipid, ΣPCBsUndisturbed = 16.97 ng/g lipid; ΣDDT Disturbed =18.47 ng/g lipid and ΣDDTUndisturbed =10.86 ng/g lipid). Benthic invertebrate biomass was also negatively correlated with concentrations of contaminants in Gammarus, supporting the biomass dilution hypothesis. Thaw slumps have large enough impacts on the physico-chemical characteristics of lakes that they alter benthic invertebrate community composition and size-structure, and contaminant concentrations in Gammarus.

Polychlorinated Biphenyls (PCBs) are persistent organic pollutants known for their toxicological effects. Though industrial production of legacy PCBs was banned in 1977, they can still be measured in nearly all environmental matrices. The Chicago Sanitary and Ship Canal (CSSC) is lined with industry and the receiving waters to the Stickney Water Reclamation Plant, the World's largest waste water treatment plant and was therefore speculated to be a potential source of PCBs to the Greater Chicago Area. Surficial sediment samples were acquired along a 45 km stretch of the CSSC, from Kedzie Ave. to Lockport. PCBs in the bulk sediment were extracted using accelerated solvent extraction while PCBs in the porewater were extracted using solid phase micro extraction. The PCBs were identified and quantified using a variation on EPA method 1668C. A total of 176 individual and coeluting PCBs were identified and quantified in this study. The sum of PCB concentrations in the bulk sediment was found to range from 70 to 4970 ng/g dry wt. The sum of PCB concentrations in the freely dissolved sediment-porewater was found to range from 2 to 366 ng/L. The bulk and porewater concentrations were used to estimate an average mass flow rate of PCBs through the CSSC of 368 kg/y. The large mass flow rate of PCBs passing through the CSSC and the fact that the CSSC connects Lake Michigan to the Mississippi River suggest that continued monitoring of PCB concentrations are necessary to better understand the transport and fate of PCBs in and out of the Great Chicago Area.

Les Québécois sont de plus en plus conscients de l’environnement qui les entoure et de l’importance d’en assurer la qualité et la pérennité. Certains phénomènes, tels les changements climatiques, l’accumulation de polluants organiques persistants et l’amincissement de la couche d’ozone, que nous qualifierons de phénomènes environnementaux diffus, sont engendrés par de multiples émetteurs de polluants et ont des effets globaux qui ne peuvent être liés à un événement précis et dont les impacts sont difficiles à identifier et à quantifier pour le moment. En l’absence de preuve quant aux effets qu’auront ces phénomènes diffus sur les citoyens et les difficultés liées à la preuve scientifique du lien causal entre ce dommage et un émetteur de polluant donné, les recours classiques en responsabilité civile et pour troubles de voisinage, prévus aux articles 1457 et 976 C.c.Q., apparaissent inopérants. Nous nous interrogeons donc sur l’existence d’un droit à l’environnement qui conférerait aux citoyens le droit de vivre dans un environnement sain et leur permettrait ainsi de réclamer que cesse toute atteinte environnementale engendrée par ces phénomènes, même si elle n’a pas d’effet directement sur eux. Considérant l’importance de l’efficacité des recours qui pourraient permettre une mise en œuvre de ce droit, nous procéderons à l’analyse de trois sources potentielles d’un droit à l’environnement sous cet angle. À cet effet, nous étudierons les recours constitutionnels et quasi-constitutionnels liés à la Charte canadienne des droits et libertés, à la Charte des droits et libertés de la personne et au recours institutionnel prévu dans la Loi sur la qualité de l’environnement. Considérant l’absence de reconnaissance suffisante d’un droit à l’environnement et de recours efficaces pour en assurer la mise en œuvre, nous proposerons ensuite des pistes de solution afin que puisse être développé un mécanisme permettant une réponse judiciaire aux phénomènes environnementaux diffus. / The quality of the environment has become a growing concern in the recent years for Quebec citizens. Phenomena such as climate change, persistent organic pollutants and the depletion of the ozone layer are caused by several sources, the effects of which cannot be distinguished one from the other and/or linked to a specific event. Furthermore, these phenomena have yet to create damage to Quebec residents in order to create the necessary standing for the introduction of legal proceedings. Also, the scientific uncertainty related to the source of potential damage and to the proof of said damage makes it impossible to legally attack the emitters of the pollutant contributing to this type of environmental phenomena under 1457 C.C.Q. or 976 C.C.Q. We have identified the 3 potential sources of a right to a clean environment which could entitle Quebec citizens to go before the courts in environmental matters, even in the absence of specific damages to their person or property. We have analysed the Canadian Charter of Rights and Freedoms, the Charter of Human Rights and Freedoms and the Environmental Quality Act and looked at the potential right to a clean environment possibly contained therein and the legal actions that could be taken to ensure their respect. Considering the weakness of what our legal system had to propose, we have developed solutions that could be put forward in order to allow the war against climate change and other environmental phenomena of the same nature to become legally actionable.

As aves marinhas são sensíveis às alterações em todos os níveis tróficos, decorrentes de variações na disponibilidade de presas e contaminação por alguns compostos, capazes de se acumular nos tecidos dos organismos e magnificar-se através da cadeia trófica. As ilhas oceânicas brasileiras abrigam importantes colônias reprodutivas de aves marinhas e, apesar de serem consideradas locais remotos, estão sujeitas à contaminação decorrente de atividades humanas. Este trabalho avaliou a presença de poluentes orgânicos persistentes (POPs) em sangue, uma matriz não-destrutiva, de seis espécies de aves marinhas no Arquipélago de São Pedro e São Paulo e na Ilha da Trindade, que possibilita o monitoramento destes indivíduos ao longo dos anos. Os resultados indicaram que os principais POPs detectados no sangue (em ng g-1 de massa úmida) foram PCBs (0,05 a 55,09), DDTs (0,01 a 17,36) e Mirex (0,01 a 5,53). A migração influenciou nos altos níveis de POPs encontrados em Pterodroma arminjoniana e a massa (g) média dos indivíduos apresentou uma forte correlação negativa com as concentrações dos compostos predominantes no sangue. O sexo das aves não contribuiu significativamente nas concentrações de POPs em espécies monotípicas, exceto para a espécie Sula leucogaster que apresenta dimorfismo sexual acentuado. O comportamento alimentar, avaliado através da análise de isótopos estáveis de carbono e de nitrogênio (δ13C e δ15N), bem como as condições biológicas de cada animal contribuíram para explicar as variações nos perfis de contaminação entre as diferentes espécies. No geral, observou-se que as concentrações de POPS nos dois locais apresentaram valores baixos e similares sugerindo a via atmosférica como principal mecanismo de entrada desses contaminantes para estas regiões. Os resultados inéditos de POPs em sangue das aves marinhas nas duas mais recentes unidades de conservação marinhas criadas no Brasil, podem contribuir como referência para o monitoramento desses compostos em longo-prazo nessas regiões. / Seabirds are sensitive to changes at all trophic levels, due to variations in prey availability and contamination by some compounds, which can be accumulated in the tissues of organisms and to be magnified through the trophic chain. The Brazilian oceanic islands harbor important seabird breeding colonies and, although they are considered remote sites, they are subject to contamination from human activities. This work evaluated the presence of Persistent Organic Pollutants (POPs) in blood, a non-destructive matrix, of six species of seabirds in the São Pedro and São Paulo Archipelago (SPSPA) and Trindade Island (TI), that allows the monitoring of these individuals over the years. The results indicated that the major POPs detected in blood (ng g-1 in wet weight) were PCBs (0.05 to 55.09), DDTs (0.01 to 17.36) and Mirex (0.01 to 5,53). Migration influenced the high levels of POPs found in Pterodroma arminjoniana and the mean mass (g) of the individuals drove a strong negative correlation with the concentrations of the predominant compounds in the blood. The gender of the individuals did not contribute significantly to the concentrations of POPs in monotypic species, except for the species Sula leucogaster that presents marked sexual dimorphism. The feeding behavior was evaluated through the analysis of stable isotopes of carbon and nitrogen (δ13C and δ15N) as well as the biological conditions of each animal contributed to explain the variations in the contamination profiles between the different species. In general, we observed that POPS concentrations at both sites presented low and similar values suggesting the atmospheric transport as the main input mechanism of these compounds for these regions. The unpublished results of POPs, in blood of seabirds from the two most recent marine conservation units created in Brazil, can contribute as reference values for their long-term monitoring in those regions.

<p>Месо шарана, најзаступљеније врсте рибе на рибњацима у<br />Републици Србији, али и других ципринидних врста, представља<br />значајан нутритивни извор n-3 високо незасићених масних киселина,<br />које имају важну улогу на здравље људи. У раду су испитани<br />фактори који делују на хемијски и маснокиселински састав меса<br />шарана и других ципринидних врста које се гаје на подручју Србије.<br />Установљено је да је садржај масти и маснокисeлински састав риба<br />су под утицајем врсте рибе, чак и када припадају истој фамилији,<br />различитих фактора животне средине, начина гајења, а посебно<br />начина исхране. Утврђен је значај добре технологије производње на<br />рибњаку за одговарајућу структуру планктонских и бентосних<br />организама, што игра велику улогу у добијању меса шарана, али и<br />других ципринидних врста, које се могу гајити у поликултури са<br />њим, доброг хемијског и маснокиселинског састава. Указано је на<br />значај који формулисане смеше имају у исхрани риба на њихово<br />здравствено стање, производне параметре и квалитет меса. Извршено<br />је испитивање замене компоненти анималног порекла са<br />алтернативним компонентама биљног порекла и добијени су<br />задовољавајући резултати у погледу производних перформанси и<br />умерених промена квалитета меса, када је у питању маснокиселински<br />ДВМ Драгана Љубојевић<br />Коришћење репичиног уља у исхрани шарана и лињака као фактора променa квалитета меса<br />iii<br />састав. Анализом седимента, воде у рибњацима, као и меса риба из<br />рибњака и отворених вода установљен је степен загађености животне<br />средине. Представљен је нови производ од меса шарана и других<br />ципринидних риба. По први пут је успостављена ћелијска култура<br />масног ткива шарана, која омогућава анализирање молекуларних и<br />биохемијских механизама који се не могу изучавати на живим<br />рибама, који настају као последица промена у исхрани.</p> / <p>Meso šarana, najzastupljenije vrste ribe na ribnjacima u<br />Republici Srbiji, ali i drugih ciprinidnih vrsta, predstavlja<br />značajan nutritivni izvor n-3 visoko nezasićenih masnih kiselina,<br />koje imaju važnu ulogu na zdravlje ljudi. U radu su ispitani<br />faktori koji deluju na hemijski i masnokiselinski sastav mesa<br />šarana i drugih ciprinidnih vrsta koje se gaje na području Srbije.<br />Ustanovljeno je da je sadržaj masti i masnokiselinski sastav riba<br />su pod uticajem vrste ribe, čak i kada pripadaju istoj familiji,<br />različitih faktora životne sredine, načina gajenja, a posebno<br />načina ishrane. Utvrđen je značaj dobre tehnologije proizvodnje na<br />ribnjaku za odgovarajuću strukturu planktonskih i bentosnih<br />organizama, što igra veliku ulogu u dobijanju mesa šarana, ali i<br />drugih ciprinidnih vrsta, koje se mogu gajiti u polikulturi sa<br />njim, dobrog hemijskog i masnokiselinskog sastava. Ukazano je na<br />značaj koji formulisane smeše imaju u ishrani riba na njihovo<br />zdravstveno stanje, proizvodne parametre i kvalitet mesa. Izvršeno<br />je ispitivanje zamene komponenti animalnog porekla sa<br />alternativnim komponentama biljnog porekla i dobijeni su<br />zadovoljavajući rezultati u pogledu proizvodnih performansi i<br />umerenih promena kvaliteta mesa, kada je u pitanju masnokiselinski<br />DVM Dragana LJubojević<br />Korišćenje repičinog ulja u ishrani šarana i linjaka kao faktora promena kvaliteta mesa<br />iii<br />sastav. Analizom sedimenta, vode u ribnjacima, kao i mesa riba iz<br />ribnjaka i otvorenih voda ustanovljen je stepen zagađenosti životne<br />sredine. Predstavljen je novi proizvod od mesa šarana i drugih<br />ciprinidnih riba. Po prvi put je uspostavljena ćelijska kultura<br />masnog tkiva šarana, koja omogućava analiziranje molekularnih i<br />biohemijskih mehanizama koji se ne mogu izučavati na živim<br />ribama, koji nastaju kao posledica promena u ishrani.</p> / <p>Meat of common carp, the most common fish species which is farmed in<br />the Republic of Serbia and meat of other cyprinid species, represent an<br />important nutritional source of n-3 highly unsaturated fatty acids, which<br />play an important role in human health. This paper examined the factors<br />that affect the chemical and fatty acid composition of carp and other<br />cyprinid species that are grown in Serbia. It was found that the fat content<br />and fatty acid composition of fish are influenced by fish species, even<br />when they belong to the same family, and also by different environmental<br />factors of cultivation, especially by diet. It was established the importance<br />of proper rearing technology in the pond for the appropriate structure of<br />planktonic and benthic organisms, which play a significant role in getting<br />carp meat, and meat of other cyprinid species that can be grown in<br />polyculture with carp of desirable chemical and fatty acid composition. It<br />was pointed out on the significance of formulated feed mixtures in fish<br />nutrition on fish health, production parameters and meat quality. An<br />investigation was done on replacing components of animal origin with<br />alternative components of plant origin and satisfactory results were<br />obtained in terms of production performance and moderate changes in the<br />quality of meat, regarding to fatty acid composition. The degree of<br />environmental pollution was established by analysis of sediment and<br />water in the ponds, and the flesh of fish from ponds and open water. The<br />new food product made from fish meat was presented. For the first time, it<br />was established cell cultures carp preadipocytes, which allows analysis of<br />the molecular and biochemical mechanisms that arise as a result of<br />ДВМ Драгана Љубојевић<br />&nbsp;</p>

Les Québécois sont de plus en plus conscients de l’environnement qui les entoure et de l’importance d’en assurer la qualité et la pérennité. Certains phénomènes, tels les changements climatiques, l’accumulation de polluants organiques persistants et l’amincissement de la couche d’ozone, que nous qualifierons de phénomènes environnementaux diffus, sont engendrés par de multiples émetteurs de polluants et ont des effets globaux qui ne peuvent être liés à un événement précis et dont les impacts sont difficiles à identifier et à quantifier pour le moment. En l’absence de preuve quant aux effets qu’auront ces phénomènes diffus sur les citoyens et les difficultés liées à la preuve scientifique du lien causal entre ce dommage et un émetteur de polluant donné, les recours classiques en responsabilité civile et pour troubles de voisinage, prévus aux articles 1457 et 976 C.c.Q., apparaissent inopérants. Nous nous interrogeons donc sur l’existence d’un droit à l’environnement qui conférerait aux citoyens le droit de vivre dans un environnement sain et leur permettrait ainsi de réclamer que cesse toute atteinte environnementale engendrée par ces phénomènes, même si elle n’a pas d’effet directement sur eux. Considérant l’importance de l’efficacité des recours qui pourraient permettre une mise en œuvre de ce droit, nous procéderons à l’analyse de trois sources potentielles d’un droit à l’environnement sous cet angle. À cet effet, nous étudierons les recours constitutionnels et quasi-constitutionnels liés à la Charte canadienne des droits et libertés, à la Charte des droits et libertés de la personne et au recours institutionnel prévu dans la Loi sur la qualité de l’environnement. Considérant l’absence de reconnaissance suffisante d’un droit à l’environnement et de recours efficaces pour en assurer la mise en œuvre, nous proposerons ensuite des pistes de solution afin que puisse être développé un mécanisme permettant une réponse judiciaire aux phénomènes environnementaux diffus. / The quality of the environment has become a growing concern in the recent years for Quebec citizens. Phenomena such as climate change, persistent organic pollutants and the depletion of the ozone layer are caused by several sources, the effects of which cannot be distinguished one from the other and/or linked to a specific event. Furthermore, these phenomena have yet to create damage to Quebec residents in order to create the necessary standing for the introduction of legal proceedings. Also, the scientific uncertainty related to the source of potential damage and to the proof of said damage makes it impossible to legally attack the emitters of the pollutant contributing to this type of environmental phenomena under 1457 C.C.Q. or 976 C.C.Q. We have identified the 3 potential sources of a right to a clean environment which could entitle Quebec citizens to go before the courts in environmental matters, even in the absence of specific damages to their person or property. We have analysed the Canadian Charter of Rights and Freedoms, the Charter of Human Rights and Freedoms and the Environmental Quality Act and looked at the potential right to a clean environment possibly contained therein and the legal actions that could be taken to ensure their respect. Considering the weakness of what our legal system had to propose, we have developed solutions that could be put forward in order to allow the war against climate change and other environmental phenomena of the same nature to become legally actionable.