Eeyou Istchee Research Articles

Vein topology, structures, and distribution during the prograde formation of an Archean gold stockwork

Abstract The Archean Cheechoo stockwork gold deposit is hosted by a felsic intrusion of tonalitic-granodioritic composition and crosscutting pegmatite dikes in the Eeyou Istchee James Bay area of Quebec, Canada (Archean Superior craton). The evolution of the stockwork is characterized herein using field relationships, vein density, and connectivity measurements on drill core and outcrop zones. The statistical distribution of gold is used to highlight mechanisms of stockwork emplacement and gold mineralization and remobilization. Two statistical populations of gold concentration are present. Population A is represented by gold grades below 1 g/t with a lognormal cumulative frequency. It is widespread in the hydrothermally altered (albite and quartz) and mineralized facies of the pluton. It is controlled by the development of quartz-feldspar-diopside veins as shown by the similar lognormal distribution of grades and vein density and by the correspondence of grades with network connectivity. Diopside and actinolite porphyroblasts in deformed veins within sodic and calcsilicate alteration zones are evidence for auriferous vein emplacement prior to the amphibolite facies peak of metamorphism. Population B (>1 g/t) is erratic and exhibits a strong nugget effect. It is present throughout the mineralized portion of the pluton and in pegmatites. This population is interpreted as the result of gold remobilization during prograde metamorphism and pegmatite emplacement following the metamorphic peak. The pegmatites are interpreted to have scavenged gold emplaced prior to peak metamorphism. These results show the isotropic behavior of the investigated stockwork during regional deformation and its development during the early stages of regional prograde metamorphism.

The Miiyupimatisiiun Research Data Archives Project

The Miiyupimatisiiun Research Data Archives Project (MRDAP) is a digitization and data transfer initiative between medical anthropologist Naomi Adelson and the Whapmagoostui First Nation (FN) in the territory of Eeyou Istchee (in northern Quebec). This report provides an overview of phase one of the MRDAP from three distinct perspectives: the researcher, the archivist, and the community. The authors discuss the history of the relationship between Adelson and the Whapmagoostui FN, the digitization process, and the work that is required to transfer the digitized materials to the community for access and safekeeping. The report also foregrounds how the project team is working to ensure that the community has full control over how the data is managed, stored, accessed, and preserved over the long term. The report provides a case study on how Indigenous data sovereignty is being negotiated in the context of one community.

Rediscovering the Tradition of Painted Caribou Belongings in Eeyou Istchee: A Community-Based and Community-Led Research Project

One of the core programming goals at Aanischaaukamikw Cree Cultural Institute is to rediscover, relearn, and reintroduce the traditions of our historic belongings through the display, study, and research of belongings currently cared for by museums outside our region. In 2017, we received funding from the Canada Council of the Arts for a multi-year research and knowledge creation project, "Rediscovering the Tradition of Painted Caribou Coats in Eeyou Istchee." Our project brought Eeyou knowledge together with surviving examples of painted caribou coats and accessories from the eighteenth and nineteenth centuries usually referred to, and classified as, "Naskapi" by museums and "experts" outside our region.

USE OF LANDSAT-8 OLI IMAGERY AND LOCAL INDIGENOUS KNOWLEDGE FOR EELGRASS MAPPING IN EEYOU ISTCHEE

Abstract. The eastern coastline of James Bay (Eeyou Istchee) is known to be home to beds of subarctic eelgrass (Zostera marina L.). These eelgrass beds provide valuable habitat and food source for coastal and marine animals and contribute valuable ecosystem services such as stabilization of the shoreline all along the coast. Despite reports from Cree communities that eelgrass bed health has declined, limited research has been performed to assess and map the spatial distribution of eelgrass within the bay. This study aims to address that issue by evaluating the capability of Landsat-8 Operational Land Imager (OLI) imagery to establish a baseline map of eelgrass distribution in 2019 in the relatively turbid waters of Eeyou Istchee. Three images acquired in September 2019 were merged and classified using Random Forests into the following classes: Eelgrass, Turbid Water, Highly Turbid Water, and Optically Deep Water. The resulting classified image was validated against 108 ground truth data that were obtained from both the eelgrass health and Hydro-Quebec research team. The resulting overall accuracy was 78.7%, indicating the potential of the Random Forests classifier to estimate baseline eelgrass coverage in James Bay using Landsat-8 imagery. This project is part of a Cree driven project, the Coastal Habitat Comprehensive Research Program (CHCRP). The CHCRP aims to combine Cree's traditional knowledge with Western science to better understand environmental changes in the coastal ecosystems and ecosystem services of eastern James Bay. The study is funded by a MITACS grant sponsored by Niskamoon Corporation, an indigenous non-profit organization.

Health measures of Eeyouch (Cree) who are eligible to participate in the on-the-land Income Security Program in Eeyou Istchee (northern Quebec, Canada)

BackgroundParticipation in on-the-land programs that encourage traditional cultural activities may improve health and well-being. The Income Security Program (ISP) − a financial incentive-based on-the-land program − for Eeyouch (Cree) hunters and trappers in Eeyou Istchee was created as a result of the 1975 James Bay and Northern Quebec Agreement to help mitigate the effects of hydroelectric development on the Cree people of northern Quebec, Canada. Beyond the ISP’s financial incentives, little is known about the health measures of those who are eligible to participate in the ISP (i.e. spent ≥120 days on-the-land during the previous year). Therefore, this paper’s objective was to assess the health measures of northern Quebec Cree, who were eligible for participation in the ISP.MethodsUsing participant data (n = 545) compiled from the Nituuchischaayihtitaau Aschii Multi-Community Environment-and-Health Study, we assessed 13 different health measures in generalized linear models with the independent variable being the eligibility to participate in the ISP.ResultsParticipants in the present study who were eligible for the ISP had significantly higher levels of vigorous and moderate activity per week, and higher concentrations of omega-3 polyunsaturated fatty acids in the blood compared to those ineligible for the ISP (i.e. spent ≤119 days on-the-land during the previous year). Encouragingly, following model adjustment for age and sex, participants eligible for the ISP did not have higher blood concentrations of mercury than those who were not eligible for the ISP.ConclusionsOur results suggest that the participants eligible for participation in the ISP are likely to be healthier than those who are ineligible to participate − and are promising for on-the-land programs for Indigenous peoples beyond a financial incentive − with no apparent higher risk of increasing contaminant body burden through traditional on-the-land-activities (e.g. fish consumption).

Environmental contaminant body burdens and the relationship with blood pressure measures among Indigenous adolescents using Bayesian Kernel Machine Regression: Results from the Nituuchischaayihtitaau Aschii: Multi-Community Environment-and-Health Study in Eeyou Istchee, Quebec, Canada, 2005–2009

Early onset hypertension among youth has important cardiovascular health implications later in life. Persistent organochlorine pollutants, polybrominated diphenyl ethers (PBDEs), and toxic metals have been associated with adverse cardiovascular outcomes. This study examined body burdens of environmental contaminants and blood pressure measurements (BP) among adolescents. We used data collected from the Multi-Community Environment-and-Health Study. First Nation adolescents with valid contaminant and BP measures were eligible. Principal Component Analysis (PCA) produced orthogonal principal component (PC) axes that were subsequently used as independent predictors in modified Poisson regression models, with robust variance estimation. Prevalence ratios (PR) with corresponding 95% confidence intervals (95% CI) were derived for elevated blood pressure (EBP), which was defined as systolic (SBP≥120 mm Hg or diastolic DBP)≥80 mm Hg according to new clinical practice guidelines for BP screening among adolescents between 13 and 19 years of age. Bayesian Kernel Machine Regression (BKMR) further examined individual contaminant contributions on continuous BP measures. In total there were ( n =148; 47 % females) First Nation adolescents. Prevalence of EBP, was 29%. Four PCs were extracted from the PCA analysis. The first axis (PC-1) explained 45% of the total variance, showing positive, primarily high loadings from polychlorinated biphenyl congeners (PCB). PBDEs loaded highly on PC-2, explaining 18% of the variation. Toxic metals (i.e., lead and mercury), and cadmium highly and positively loaded on PC-3 and PC-4, accounting for 11% and 10% of the variation, respectively. EBP was significantly associated with increasing PC-2 (i.e., PBDEs) across all adjusted models, fully adjusted model (PR=1.21; 95% 1.05, 1.40). Results from BKMR bolster the findings from the PCA and regression models. In this cross-sectional analysis, exposure to PBDE, specifically, PBDE-47 may adversely affect BP measures among young First Nation adolescents in Canada.

Examining chronic inflammatory markers on blood pressure measures in the presence of vitamin D insufficiency among indigenous cree adults: results from the cross-sectional Multi-Community Environment-and-Health Study in Eeyou Istchee, Quebec, Canada

ObjectiveHigh blood pressure (BP) is a risk factor for cardiovascular disease. Examining the role of inflammatory mediators on BP is important since vitamin D (VD) is a modifiable risk factor,...

On Nation-to-Nation Partnership and the Never-Ending Business of Treaty-Making: Reflections on the Experience of the Crees of Eeyou Istchee (Eastern James Bay)

This article discusses the successes of the Crees of Eeyou Istchee in the continual negotiation and renegotiation of their treaty relationship with the Quebec and Canadian governments but also queries how arrangements reached during more than four decades of treaty relationship, charting a course of proliferating entanglements with resource-extractive capitalism and state administration, both express and diverge from the “community of life” relational ontology of Cree activity on the land. While the Crees of Eeyou Istchee have achieved important successes in negotiating economic equity and territorial self-government and have not allowed themselves to be trapped in a once-and-for-all “settlement” of their rights, their negotiations with the state and with corporate entities reward certain Cree interests and positions over others. Compromises have occurred and development pathways chosen that increasingly challenge those who maintain as political priorities the defence of ecological diversity and integrity and accompanying Cree lifeways. Incommensurable premises of liberal capitalism and statehood have inhibited the conditions for the reproduction of Cree relationality, however nimbly the latter grapples with the former in reaching successive treaties and agreements Dans cet article, je me penche sur les succès obtenus par les Cris de Eeyou Istchee dans la (re)négociation perpétuelle de la relation de traité qu’ils entretiennent avec les gouvernements du Québec et du Canada. En même temps, j’explore comment la relation de traité, qui a dessiné pendant plus de quatre décennies des enchevêtrements proliférants avec le capitalisme d’extraction et l’administration étatique, reflètent tout en s’en distinguant l’ontologie relationnelle de type « communauté de vie » qui caractérise l’activité des Cris sur le territoire. Bien que les Cris de Eeyou Istchee aient engrangé d’importants succès dans la négociation de l’équité économique et de l’autonomie territoriale, et bien qu’ils ne se soient pas laissés piéger dans un « règlement » définitif de leurs droits, les négociations engagées avec l’État et les corporations ont favorisé certains intérêts et positionnements Cris par rapport à d’autres. Les compromis réalisés et les voies de développement empruntées mettent de plus en plus au défi ceux dont les priorités politiques restent la défense de la diversité et de l’intégrité écologiques et l’accompagnement des modes de vie cris. En ce sens, les présupposés incommensurables du capitalisme libéral et de l’État entravent la reproduction de la relationnalité crie, même si cette dernière lutte habilement contre les premiers dans la conclusion des traités et des ententes successives.

Potential obesogenic effect of a complex contaminant mixture on Cree First Nations adults of Northern Québec, Canada

BackgroundObesity incidence and prevalence is of increasing concern in First Nations communities around Canada. In addition to diet and physical activity, environmental pollutants have been suggested as a potential contributory factor to obesity associated morbidity. Owing to the exposure of Cree First Nations people to various persistent organic pollutants (POPs) and toxic metals, it is important to examine the association between obesity in these communities, and contaminant body burdens. ObjectiveTo determine whether selected morphometry measures (body mass index [BMI], waist circumference [WC] and body fat percentage) are associated with body burdens of 10 POPs and toxic metals. MethodsUsing data from the Nituuchischaayihtitaau Aschii Multi-community Environment-and-Health study in the eastern James Bay (Eeyou Istchee) Cree communities, this cross-sectional study examined morphometric and contaminant measures of 695 eligible participants. Sex stratified principal component analysis was conducted on blood plasma concentrations of 10 POPs and toxic metals. BMI, WC, body fat percent, and resultant contaminant components were used to create generalized linear models, and adjusted for covariates (age, total lipids, smoking, and n-3 fatty acids). ResultsTwo principal components (PCs; PC-1 and PC-2) were extracted for both males and females. For females, PC-1 explained 73.3% and PC-2 explained 10.5%, and for males, PC-1 explained 71.6% and PC-2 explained 11.2% of the variance in contaminant burden. For both sexes, PC-1 loaded highly for polychlorinated biphenyl (PCB) congeners, organochlorine pesticides and, to a lesser extent, mercury and lead. PC-2 loaded highly for cadmium for females, and cadmium and lead for males. After adjusting for covariates, the generalized linear model showed that PC-2 was significantly and negatively associated with BMI, body fat percent, and WC in males and females. ConclusionsOur cross-sectional analysis indicates a negative association between cadmium with various obesity measures in both males and females. Null associations were found between PCBs and organochlorine pesticides and morphometry.

Fisher's Linear Discriminant Function Analysis and its Potential Utility as a Tool for the Assessment of Health-and-Wellness Programs in Indigenous Communities.

Diabetes mellitus is a growing public health problem affecting persons in both developed and developing nations. The prevalence of type 2 diabetes mellitus (T2DM) is reported to be several times higher among Indigenous populations compared to their non-Indigenous counterparts. Discriminant function analysis (DFA) is a potential tool that can be used to quantitatively evaluate the effectiveness of Indigenous health-and-wellness programs (e.g., on-the-land programs, T2DM interventions), by creating a type of pre-and-post-program scoring system. As the communities of the Eeyou Istchee territory, subarctic Quebec, Canada, have varying degrees of isolation, we derived a DFA tool for point-of-contact evaluations to aid in monitoring and assessment of health-and-wellness programs in rural and remote locations. We developed several DFA models to discriminate between those with and without T2DM status using age, fasting blood glucose, body mass index, waist girth, systolic and diastolic blood pressure, high-density lipoprotein, triglycerides, and total cholesterol in participants from the Eeyou Istchee. The models showed a ~97% specificity (i.e., true positives for non-T2DM) in classification. This study highlights how varying risk factor models can be used to discriminate those without T2DM with high specificity among James Bay Cree communities in Canada.

Heart rate variation and human body burdens of environmental mixtures in the Cree First Nation communities of Eeyou Istchee, Canada

IntroductionHeart rate variability (HRV) is a measure of cardiac autonomic regulation that examines the variation in beat-to-beat fluctuations in heart rate. While many exposure-based studies have examined the effects of single or similar groups of contaminants on HRV parameters, none have examined the association between complex environmental mixtures, including organic and elemental contaminants, and HRV. MethodsUsing data collected from the Multi-Community Environment-and-Health Study in Eeyou Istchee (Quebec, Canada), we assessed HRV in two time domain measures: root mean square of successive differences (RMSSD) and standard deviation of the N-N (RR) intervals (SDNN); and in three frequency domains: high frequency (HF), low-frequency (LF), and very-low frequency (VLF) in 443 participants. We first examined mixture effects of nineteen organic and metal contaminants in blood using principal component analysis (PCA) and a multivariable general linear regression on HRV responses, adjusting for age, sex, body mass index, smoking status, and kidney disease covariates. We subsequently assessed HRV outcome response variables using Bayesian kernel machine regression (BKMR) to further examine individual contaminant contribution and overall mixture effects. ResultsIn the PCA, a significant positive association was observed between RMSSD and principal component (PC) axis 2, which was highly positively-loaded for nickel and moderately negatively-loaded for mercury. A negative association between SDNN and PC-1, which was highly positively-loaded for all PCBs (polychlorinated biphenyls) and organochlorines and moderately positively-loaded for mercury, was observed. Additionally, a significant and positive association was observed between PC-2 and SDNN and a significant and negative association between PC-3 (negatively loaded for cadmium) and LF. Associations with contaminants were not observed for HF or VLF. BKMR results suggest that trans-nonachlor and cis-nonachlor are primarily responsible for reductions in HRV; however, their contributions to HRV deficits was non-significant when examined as a complete mixture. ConclusionsWhile PCA results suggested that organochlorines, mercury, nickel, and cadmium may all play a role in altering various HRV, subsequent BKMR analysis illustrated the individual components driving these effects may be trans- and cis-nonachlor and nickel and likely not mercury or cadmium. However, other contaminants appear to temper this effect when the entire mixture of chemicals is assessed as a whole. This study expands our knowledge of the effects of environmental contaminant mixtures on HRV, which is especially important in exposed populations such as those in the Eeyou Istchee territory, whilst utilizing novel statistical methods such as PCA and BKMR to examine co-exposures concurrently.

Using a geographic information system to assess local scale methylmercury exposure from fish in nine communities of the Eeyou Istchee territory (James Bay, Quebec, Canada)

Exposure to methylmercury is a concern for those who rely on fish as a traditional food in the Eeyou Istchee territory of James Bay, Quebec, Canada, because industrial land uses overlap with community water bodies where fish are harvested. Consequently, this study assessed if traditional practices, particularly fishing, increased the risk of exposure to methylmercury from the consumption of locally harvested fish. We designed a geographic information system (GIS) that included land use and fish methylmercury tissue concentrations to assess clustering of potential hot spots. We also used generalized linear models to assess the association of fish consumption to blood organic-mercury concentrations, and logistic regression models to assess the probability of fish exceeding the safety threshold for methylmercury tissue concentrations in areas of high intensity land use. The GIS demonstrated significant clustered hot spots around regions of hydroelectric and mining land use. Our results also revealed that adult consumption of pike, lake trout and/or walleye, and child consumption of pike or walleye were significantly associated with blood organic-mercury concentrations. Further, large fish harvested in a community with high intensity land use yielded a 77% probability that the fish exceeded the safety threshold. From a human exposure perspective, our study highlights the need for further research on children who consume fish from this region.

Subsistence fishing in the Eeyou Istchee (James Bay, Quebec, Canada): A regional investigation of fish consumption as a route of exposure to methylmercury

Fishing is part of the traditional activities of Indigenous people in Canada. However, it is also a route of exposure to methylmercury, a known neurotoxicant, and this is a concern for those who rely on fish as part of their diet. The probable weekly intake (PWI) of methylmercury from six species of fish was calculated for Indigenous community members (N = 1406), grouped by age and sex, and compared to Canadian and international provisional reference doses to assess exposure. Mixed-effects regression models were also used to estimate the input of methylmercury into the blood, and Hazard Quotients (HQ) were used to assess potential effects. Of the species of fish in our study, walleye and lake trout contributed the most to methylmercury intake. There was a positive association between the consumption of walleye and the total blood mercury concentrations of mercury in women and men (R2A = 0.40 and 0.47, respectively), and to a lesser extent, children. Similar results were observed for the consumption of lake trout. The 95th-percentile HQ for girls (3.16) and boys (3.18) from the consumption of lake trout was relatively high, and to a lesser extent, so was the HQ for walleye and pike. The consumption of some species of fish increases the exposure to methylmercury, however, taking a balanced approach, there are health benefits associated with the consumption of fish that must be considered. To mitigate future exposure to methylmercury, we recommend follow-up blood monitoring and local-geospatial-based assessments.

Anthropological perspectives on Miyupimaatisiiun and the integration of oral health in primary care in the Cree communities of Northern Quebec.

The integration of primary oral health care has a pivotal role in improving oral health outcomes and providing accessible and affordable health care. This article contributes to the deep understanding of the cultural aspects of the integration of oral health into primary health care at an Indigenous health organization. Proceeding from a collaborative and interdisciplinary research project evaluating the integration of oral health care within primary care in Eeyou Istchee, this research is based on group discussions (6) and individual interviews (36) with 74 participants (care providers, administrators, and patients) held in four Eastern James Bay Cree communities. This study anthropologically explored participants' perceptions about primary health care conceptualizations, culturally based approaches, and experiences of oral care services at this organization using a "two-eyed seeing" Indigenous framework. The study identified three key factors related to the integration of primary oral health care: Cree perception of primary health and oral health care, cultural safety, and health provider-patient communication and the role of silence. Study findings reflected a dichotomy of perception of primary health care and the relevant units of care between the Cree structural and cultural perspective and the non-Cree professional perspective. The Cree people perceived "household" as a unit of care in comparison to non-Cree who viewed "health care services" as units of care. Our results also underline the role of cultural safety agents to address the needs for cultural competence and the role of silence as implicit cultural protocol. Our anthropological analysis illustrates the potential for increasing the level of appreciation for both users and workers in oral care in the future by ameliorating communication skills and intercultural knowledge.

Association between exposure to persistent organic pollutants and mercury, and glucose metabolism in two Canadian Indigenous populations

BackgroundThe body burden of metals and persistent organic pollutants (POPs) is particularly high in populations that rely on fish and other marine species for sustenance. This exposure has been associated with an increased risk of type 2 diabetes, but results remain contrasted. ObjectiveWe studied this association in two Indigenous populations of northern Québec (Canada) with markedly different prevalences of diabetes and levels of exposure to POPs and mercury. MethodsAs part of health surveys conducted in 2004–2009, diabetes prevalence and glucose metabolism (glucose, insulin, HOMA-IR, HOMA-B) in non-diabetic fasting adults were assessed using similar protocols in two populations: Inuit from Nunavik (n = 877) and Cree from Eeyou Istchee territory (n = 780). Blood mercury, plasma polychlorinated biphenyls (PCBs), organochlorine (OC) pesticides/metabolites and polybrominated diphenylethers (PBDEs) levels were measured in samples collected at the time of examination. Logistic and linear regressions and restricted cubic splines analyses were conducted adjusting for sex, age, waist circumference, smoking and omega-3 fatty acid content in plasma phospholipids. ResultsDiabetes prevalence was higher in Cree (20%) than in Inuit (7%), whereas environmental exposure was 2 to 3-fold greater in Inuit than in Cree participants. In the range of exposure common to the two populations, we observed similar linear increases in the risk of diabetes with increasing contaminant exposure. Among Cree participants, fasting glucose was positively associated with plasma PBDE level, and HOMA-B negatively associated with concentrations of ∑PCBs, dichlorodiphenyldichloroethylene, PBDEs and ∑OC pesticides. Among Inuit participants, a trend towards reduced insulin secretion was observed in association with most contaminants, but the relation was nonlinear (greater reduction at intermediate levels of exposure). A significant increase in fasting glucose levels was observed at elevated blood mercury levels (>16 μg/L). ConclusionThe observed association between POPs exposure and diabetes risk in the two populations studied should be confirmed using prospective design. Our results suggest the need for additional research on the physiopathological process through which POPs exposure may induce type 2 diabetes in these Indigenous populations.

Complex contaminant mixtures and their associations with intima-media thickness

BackgroundThe burden of cardiovascular disease (CVD) morbidity and mortality is higher among Indigenous persons, who also experience greater health disparities when compared to non-Indigenous Canadians, particularly in remote regions of Canada. Assessment of carotid intima-media thickness (cIMT), a noninvasive screening tool and can be used as biomarker to assess increased CVD risk. Few studies have examined environmental contaminant body burden and its association with cIMT.MethodsData from the Environment-and-Health Study in the Eeyou Istchee territory of northern Québec, Canada was used to assess complex body burden mixtures of POPs, metals and metalloids among (n = 535) Indigenous people between 15 and 87 years of age with cIMT. First, Principal Component Analysis (PCA) was used to reduce the complexity of the contaminant data. Second, based on the underlying PCA profiles from the biological data, we examined each of the prominent principal component (PC) axes on cIMT using multivariable linear regression models. Lastly, based on these PC axes, cIMT was also regressed on summed (Σ) organic compound concentrations, polychlorinated biphenyl, perfluorinated compounds, respectively, ∑10 OCs, ∑13 PCBs, ∑3PFCs, and nickel.ResultsMost organochlorines and PFCs loaded primarily on PC-1 (53% variation). Nickel, selenium, and cadmium were found to load on PC-5. Carotid-IMT was significantly associated with PC-1 β = 0.004 (95 % CI 0.001, 0.007), and PC-5 β = 0.013 (95 % CI 0.002, 0.023). However, the association appears to be greater for PC-5, accounting for 3% of the variation, and mostly represented by nickel. Results show that that both nickel, and ∑3PFCs were similarly associated with cIMT β = 0.001 (95 % CI 0.0003, 0.003), and β = 0.001 (95 % CI 0.0004, 0.002), respectively. But ∑10OCs was significantly associated with a slightly greater β = 0.004 (95 % CI 0.001, 0.007) cIMT change, though with less precision. Lastly, ∑13PCBs also increased β = 0.002 (95 % CI 0.0004, 0.003) cIMT after fully adjusting for covariates.ConclusionOur results suggest that environmental contaminants are associated with cIMT. This is important for the Cree from the Eeyou Istchee territory who may experience higher body burdens of contaminants than non-Indigenous Canadians.

Examining environmental contaminant mixtures among adults with type 2 diabetes in the Cree First Nation communities of Eeyou Istchee, Canada

Type 2 diabetes mellitus (T2DM) disproportionately affects Indigenous populations. It is possible that exposure to complex mixtures of environmental contaminants contribute to T2DM development. This study examined the association between complex environmental contaminant mixtures and T2DM among Canadian Indigenous communities from the Eeyou Istchee territory, Quebec, Canada. Using data from the cross-sectional Multi-Community Environment-and-Health Study (2005–2009) Principal Component Analysis (PCA) was used to reduce the dimensionality of the following contaminants: 9-polychlorinated biphenyl congeners; 7-organic pesticides; and 4-metal/metalloids. Following this data reduction technique, we estimated T2DM prevalence ratios (PR) and 95% confidence intervals using modified Poisson regression with robust error variance across derived principal components, adjusting for a priori covariates. For both First Nation adult males (n = 303) and females (n = 419), factor loadings showed dichlorodiphenyltrichloroethane (DDT) and lead (Pb) highly loaded on the second principal component (PC) axis: DDT negatively loaded, and Pb positively loaded. T2DM was significantly associated with PC-2 across all adjusted models. Because PCA produces orthogonal axes, increasing PC-2 scores in the fully adjusted model for females and males showed (PR = 0.84; 95% CI 0.72, 0.98) and (PR = 0.78; 95% CI 0.62, 0.98), respectively. This cross-sectional study suggests that our observed association with T2DM is the result of DDT, and less likely the result of Pb exposure. Further, detectable levels of DDT among individuals may possibly contribute to disease etiology.

Environmental contaminant body burdens and the relationship with blood pressure measures among Indigenous Canadians

OPS 18: Cardiometabolic effects of chemical exposures, Room 110, Floor 1, August 26, 2019, 1:30 PM - 3:00 PM Blood pressure (BP) increments increase cardiovascular disease (CVD) risk. Recently, clinical practice guidelines lowered hypertension definitions. Indigenous Canadians experience slightly higher CVD compared to non-Indigenous Canadians. Environmental contaminant body burden from persistent organochlorine pollutants, organic compound concentrations (OCs), and metals have been linked with hypertension risk. This study examined the role of OCs, and metals on hypertension among Indigenous Canadians. Methods: Using data from the Environment-and-Health Study in Eeyou Istchee territory of northern Québec, Canada, the sample restricted to adults over 20-years of age, with valid BP measures and detectable body burden mixtures. In total, n=774 participants were eligible, of which, n=452, 58% females. Principal Component Analysis (PCA) was used to reduce the complexity of the contaminant data. Orthogonal principal component (PC) variables were used as independent predictors in both multivariable linear regression, and modified Poisson regression models with robust variance estimation, deriving relative risk for hypertension defined using systolic BP (SBP) ≥140 mm Hg or diastolic BP (DBP) ≥90 mm Hg. Results: Three PCs were extracted from the PCA analysis. PC-1, PC-2, and PC-3, explained 72%, 5.5% and 4.8% of the variation, respectively. Polychlorinated biphenyls and OCs positively highly loaded on the first axes (PC-1), followed by moderate loadings for metal mercury. Lead loaded positively, whereas DDT negatively loaded on PC-2, and cadmium strongly loaded on the third PC axis. Systolic BP measures were significantly associated with PC-1 across all models. In the final model, PC-1 increased SBP β=1.72 (95% CI 0.42, 3.02). PC-3, represented by cadmium was associated with SBP but after adjusting for body mass, PC-3 was no longer associated with SBP. Hypertension was consistently and significantly associated with PC-1 across models, RR=1.14 (95% CI 1.02, 1.28) in the final adjusted model. Conclusion: Using a reduction technique, this cross-sectional analysis found OCs to be associated with increased SBP.

121 - Partnering With the Cree to Develop a Diabetes Prevention Strategy in Families With Prior Gestational Diabetes: In-Depth Interview Results

The prevalence type 2 diabetes (DM2) in Eeyou Istchee Cree communities are rapidly rising. Women with a history of gestational diabetes mellitus (GDM) and their families are at high risk for DM2. The local health board has programs for diabetes management, but identified gaps in diabetes prevention.

Topological characterization of a polyphased gold-bearing vein network

It is challenging to evaluate the connectivity of metal-bearing hydrothermal vein systems, i.e. the degree to which fractures or veins are connected within a network. Moreover, many ancient ore-bearing vein networks have been deformed and metamorphosed, which hinders the reconstruction and quantification of their primary characteristics. Here, we explore the reliability and limitations of the network distribution and topologic (classification of vein terminations into I, Y and X nodes) approaches to study deformed and metamorphosed mineral deposits. We focus on the Cheechoo gold deposit located in the Eeyou Istchee James Bay area of Quebec, Canada (Archean Superior Province). This gold deposit shows a complex hydrothermal and magmatic polyphased gold-bearing vein system hosted in a granodioritic-tonalitic intrusion. The Cheechoo deposit is composed of quartz-feldspar-diopside (Qtz-Fsp-Di) and quartz (Qtz) veins that underwent ductile deformation and amphibolite facies metamorphism.The high-grade metamorphism led to the modification of vein shape, relative position and spacing, making these parameters unreliable for the characterization of the Cheechoo vein system and similar metamorphosed networks. However, the number of veins per length unit and topology are reliable tools to characterize such networks. In the gold-bearing Cheechoo system, the gold mineralization appears to be mainly controlled by (i) the number of Qtz and Qtz-Fsp-Di veins per length unit and by (ii) the connectivity of these networks as shown by the increase of both parameters with the gold grade.Furthermore, we introduce the Y/I ratio as a simple topological parameter to quantify the connectivity of two dimensional (I-Y dominated) systems. This parameter is positively correlated with the number of connections per branch (CB) used to quantify network connectivity, and ultimately represent the development of a fault or fracture zone.