Environmental health

Cadmium is a toxic metal that has detrimental effects on blood vessel development and function. To examine the effect of varying concentrations of cadmium on angiogenesis, two in vitro assays were used. First, developing yolk sac blood vessels were studied in gestation day 8 mouse embryos exposed to medium alone, 1.25, or 1.75 μM cadmium chloride (CdCl2). Embryos exposed to 1.25 μM cadmium experienced a significant increase in the number of vessels formed; however, they were smaller in size. Vessel morphology and signalling pathways were also investigated using the mouse aortic ring assay, with exposures of 0.0, 0.5, 1.0, 5.0, or 10.0 μM CdCl2. Samples exposed to 10 μM experienced a significant increase in vessel length. However, no significant differences in phosphorylated PTEN and AKT were observed. The results of this study suggest that low levels of cadmium may disrupt angiogenesis, particularly the development of the embryonic vasculature in the yolk sac.

Author Keywords: Angiogenesis, Cadmium, Embryonic Development, Teratogenicity, Vascular Development, Vasculogenesis

Children may be spending less time outdoors in nature than in previous generations, with one potential reason being parents in their role as 'gatekeepers' to the outdoors. This study investigated how families are spending their time during the COVID-19 pandemic, and how parents may influence children's outdoor nature experiences. Parents (N = 121) from across Canada completed measures related to their family's activities as well as their own connection with nature, attitudes about nature, and childhood nature contact. Results suggest that having easy access to nature, a greater connection with nature, believing in the importance of outdoor experiences, and doing outdoor activities in childhood may be associated with more current family time outside in nature. By understanding the reasons behind parental decisions regarding where and how families spend time outside, strategies can be developed to help parents increase their children's nature time in the future.

Author Keywords: children, family, nature, nature-relatedness, outdoors, parents

Addressing the issue of food insecurity effectively within a region in a way where interventions reflect the variability of food insecurity levels across subgroups of the population is important. It is a unique challenge and requires specific data. This study took in this direction by conducting an exploratory statistical analysis of a community-representative dataset of Inuit Seniors' food (in)security. The analysis was theoretically sensitive as well as knowledge-user-directed.Results show that 52.7% of all Seniors in Nain and Hopedale, Nunatsiavut, are food insecure, and that food (in)security is associated with age group, education status, health status, mobility status and household financial situation. Further, younger Seniors aged 55-64 are more likely to be food insecure than their older peers. This study is among the first to provide an analysis of quantitative associations between variables that characterize food (in)security among a specific subgroup in the Inuit population.

Author Keywords: Arctic, Case study, Food security, Inuit health, Seniors, Vulnerability

Plastic pollution is a growing concern, owing to its durability, ubiquity, and potential health impacts. The overall objective of this study was to assess the abundance and distribution of microplastics within Lake Scugog catchment, Ontario. This was fulfilled through two tasks (i) the development of a microplastic particle budget for the lake catchment, and (ii) the determination of the dry deposition of atmospheric microplastics in Port Perry, Ontario. The total input of microplastics into Lake Scugog (atmospheric deposition and stream inflow) was 2491 x106 mp/day, while the output (lake outflow and sedimentation) was 1761 x106 mp/day, suggesting that 29% of inputs were retained in the lake. The dry deposition of microplastics in Port Perry was 1257 mp/m2/day, which was high when compared to bulk deposition (37 mp/m2/day) in the same area. By quantifying the major pathways of microplastics better management techniques can be implemented.

Author Keywords: Catchment, Dry Deposition, Microplastics, Ontario, Particle Budget, Plastic pollution

This thesis sought to explore and evaluate perceptions of food needs and the role of a community freezer in addressing those needs, among Inuit in Hopedale, Nunatsiavut (Northern Labrador). Research was carried out through an exploratory sequential mixed-methods design. Phase 1 employed qualitative interviews with community members in Hopedale to explore the perceptions of food needs from an Inuit perspective. Results from Phase 1 identified a series personal, physical, cultural, and social food needs that informed the development of a series of questions that were integrated into a community-wide survey that was implemented in Phase 2. Results from Phase 2 identified a series of cultural, household and individual characteristics that significantly impact perceived ability to meet needs among community members in Hopedale. Findings from this research contribute to our understanding of food needs, and may potentially influence estimates of levels of needs that are protected in Inuit land claims, and inform the development or improvement of community methods for food support.

Author Keywords: Food Needs, Food Programs, Food Security, Indigenous, Inuit, Mixed-Methods

The potential impacts of domestic wastewater (DWW) on the source of drinking water for the M'Chigeeng First Nation were monitored as part of the development of a Source Water Protection plan. During a period of continuous overflow of the Gaaming Wastewater Lagoon serving the community, the chemical tracers, caffeine and sucralose were tracked in West Bay with Passive Organic Chemical Integrative Samplers (POCIS). From the results, we speculated that DWI impacts could have been from three possible DWW sources. POCIS deployed above and below the thermocline indicated a higher mean sucralose concentration of 2.52 ± 1.83 ng/L in the hypolimnion of West Bay relative to mean epilimnetic sucralose concentrations of 0.56 ± 0.02 ng/L, suggesting possible wastewater percolation with an estimated time of travel of 61.5 days. Microbial loads of 200 CFU/100 ml E. coli from the lagoon overflow into Mill Creek decreased to 60 CFU/100 ml before entering West Bay. West Bay's wastewater assimilative capacity met Provincial Water Quality Objectives in the epilimnion and hypolimnion except for dissolved oxygen in the hypolimnion at 4.16 ± 1.86 mg/L, which is a threat to the onset of hypoxia for fish (i.e. <5 mg/L). Assimilative capacity results support a Fall lagoon discharge.

Author Keywords: caffeine, drinking water, Passive Organic Chemical Integrative Samplers (POCIS), sucralose, thermocline, wastewater

Although a wealth of research supports nature's beneficial effects on well-being, a lack of attentiveness and appreciation for nature may prevent people from fully experiencing nature's benefits. A mindfulness-based nature intervention was tested across two studies to investigate whether gratitude and mindfulness can boost nature's effects for well-being. Students completed activities across a one-week (Study 1; N = 129) and two-week (Study 2; N = 130) intervention. Students in both studies experienced significant declines in positive and negative emotion over time. Study 1 did not show the expected increases in gratitude and connection to nature. Study 2 found that students who simply spent time in nature experienced fewer negative emotions and greater increases in trait gratitude than those who were asked to gratefully reflect on their natural surroundings. Both studies found positive correlations between trait gratitude, mindfulness, well- being and connection to nature. Implications and suggestions for future research are discussed.

Author Keywords: Gratitude, Intervention, Mental Heath, Mindfulness, Nature, Well-being

Environmental factors play a critical role in the health and well-being of people worldwide and the distribution of the burden of disease associated with environmental causes is disproportionately high in marginalized populations, including First Nations. In this way, environmental health problems are as much social and political problems as environmental and must be addressed as such. In Canada, the division of responsibilities for environmental health, in combination with the jurisdictional complexities of health and environment regulation and service provision on-reserve creates a First Nations environmental health management system with significant gaps. This research set out to explore the question: What are the current strengths and challenges in First Nations environmental health policy and management? A qualitative exploratory design organized in two stages and employing key informant interviews, document review and a community case study was used to examine this topic. In the first stage a review of existing programs and policies applicable to Ontario First Nations and a series of interviews with key experts on the topic in the province were conducted. A conceptual framework of the core elements affecting environmental health management in First Nations communities was developed and then applied to a case study with Mississauga First Nation in Northern Ontario. The framework included five core elements: Environmental Health Jurisdiction and Responsibility; Participation in Environmental Health Decision-Making; Access to Environmental Health Resources, Communication of Environmental Health Information; and, Role and Influence of Leadership. The findings indicate that "internal" issues, like community-based decision-making and support for environmental health initiatives seem to be least affected by the "external" issues such as access to federal funding. The "internal" issues were also shown to be critically important factors having impacts on environmental health management practices and policies in Mississauga First Nation. While there are countless barriers associated with the "external" factors that have significant impacts on environmental health management practices and policies, this research suggest that the "internal" factors can potentially be the most important factors in creating positive change in this area and as a result warrant further study in order to improve the state of environmental health issues in First Nations.

Author Keywords: Community, Environmental Health, First Nations, Framework, Policy

Owen Sound Bay, which is located within the traditional territory of the Saugeen Ojibway Nation (SON), is contaminated as a result of historical industrial and shipping activity. Gross contamination of the sediments in the inner part of the Bay (i.e., Owen Sound Harbour) includes high concentrations of polycyclic aromatic hydrocarbons (PAHs) and other organic compounds, as well as metals that may pose a risk to the SON fishery for lake whitefish (Coregonus clupeaformis). However, evaluating the environmental risks posed by contaminated sediments is a challenge, as these risks are dependent upon several factors and require multiple lines of evidence. Including Indigenous communities in environmental risk assessment and the management of those risks is vital for sustaining ecosystem integrity, as well as respecting Treaty Rights. In this study, a risk assessment framework was developed that included several risk assessment tools used in Western science and also encompassed the concerns and values of the SON, including the application of SON-ecological knowledge. Methods for risk evaluation included gathering lines of evidence though community workshops, as well as field sampling in the Bay to determine the concentrations of PAHs and other organic contaminants in sediments and in the water column. Laboratory studies of toxicity to early life stages of lake whitefish and Japanese medaka (Oryzias latipes) and sediment disturbance simulations to evaluate biological responses in juvenile lake whitefish were also completed as lines of evidence. The results indicate that leaving the harbour "as is" without a thorough analysis of remediation options fails to address the concerns of the people within the SON communities. Overall, this research demonstrated a successful process for developing a collaborative risk assessment framework that recognizes the sovereignty of Indigenous peoples and promotes Nation-to-Nation decision making.

Author Keywords: biomarkers, Coregonus clupeaformis, Indigenous knowledge, polycyclic aromatic hydrocarbons, risk assessment, source tracking