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

Understanding heavy metal toxicity: Implications on human health, marine ecosystems and bioremediation strategies

Heavy metals are constituents of the natural environment and are of great importance to both natural and artificial processes. But in recent times the indiscriminate use of heavy metals especially for human purposes has caused an imbalance in natural geochemical cycles. This imbalance has caused contamination of heavy metals into natural resources and such as soil and a marine ecosystem. Long exposure and higher accumulation of given heavy metals are known to impose detrimental and even lethal effects on humans. Conventional remediation techniques of heavy metals provide good results but have negative side effects on surrounding environment. The role played by microbes in bioremediation of heavy metals is well reported in the literature and understanding the role of molecules in the process of metal accumulation its reduction and transformation into less hazardous state, has myriads of biotechnological implications for bioremediation of metal-contaminated sites. The current review presents the implications of heavy metals on human health and marine ecosystems, conventional methods of heavy metal removal and their side effects on the environment. Bioremediation approaches have been discussed as well in this review, proving to be a more sustainable and eco-friendly approach towards remediation of heavy metals.

A follow-up geospatial analysis and probabilistic human health risk assessment of methylmercury in fish in Eeyou Istchee (Québec, Canada)

The Cree Peoples of the Eeyou Istchee territory (northern Québec, Canada) rely on fish as a part of their traditional and contemporary diet. Fish is a culturally significant food and a source of nutrients, but it is also the main pathway of methylmercury (MeHg) exposure for humans. Significant hydroelectric developments in this territory are responsible for increasing the concentrations of MeHg found in fish and thus increase the human exposure to this neurotoxic compound. As this is an ongoing issue, our study assessed the current MeHg fish-tissue concentrations in Eeyou Istchee and the spatial distribution of MeHg hot spots using Geographic Information Systems (GIS) to compare our results to those found in previous studies from the same region. We also performed a probabilistic hazard assessment of the exposure to MeHg from fish consumption. The GIS models indicated significant clustering of increased MeHg fish-tissue concentrations around hydroelectric reservoirs and showed higher MeHg fish-tissue concentrations around newer hydroelectric reservoirs, but a decrease in older reservoirs. Similar to past studies, we found that fish consumption continues to pose an MeHg exposure hazard for men who consume large piscivore species (i.e., lake trout, walleye, and pike), while for women, lake trout and walleye consumption constitute a hazard (any size), and pike should be consumed with caution. The hazard of exposure was mainly associated with intake rate in all cases. Lastly, we recommend monitoring MeHg fish-tissue concentrations in this region, as the MeHg tissue concentrations remain elevated, and updated consumption guidelines where and when necessitated.

Metals on the Menu-Analyzing the Presence, Importance, and Consequences

Metals are integral components of the natural environment, and their presence in the food supply is inevitable and complex. While essential metals such as sodium, potassium, magnesium, calcium, iron, zinc, and copper are crucial for various physiological functions and must be consumed through the diet, others, like lead, mercury, and cadmium, are toxic even at low concentrations and pose serious health risks. This study comprehensively analyzes the presence, importance, and consequences of metals in the food chain. We explore the pathways through which metals enter the food supply, their distribution across different food types, and the associated health implications. By examining current regulatory standards for maximum allowable levels of various metals, we highlight the importance of ensuring food safety and protecting public health. Furthermore, this research underscores the need for continuous monitoring and management of metal content in food, especially as global agricultural and food production practices evolve. Our findings aim to inform dietary recommendations, food fortification strategies, and regulatory policies, ultimately contributing to safer and more nutritionally balanced diets.

Measurement of diet quality among First Nations peoples in Canada and associations with health: a scoping review

BACKGROUND

Given the increasing number and the diversity of dietary quality indices used for research, and the differences between settings, there is a need to identify valid indices of dietary quality in different contexts and populations and to identify their associations with health-related outcomes.

OBJECTIVES

The primary objective of this scoping review is to identify the tools used in determining dietary quality among First Nations and to describe the changes in diet. The second objective is to describe the associations identified in studies that have measured the relationship between health and dietary quality among First Nations; and the third objective is to identify factors associated with diet quality.

METHODS

PubMed, Embase, CINAHL, Global Health, and Web of Science were searched from inception to June 2021 and updated in February 2022. Articles were included if the research subjects were First Nations, or if articles reported disaggregated subset data for First Nations. Eligible studies focused on nutrition and diet and were published in English or French.

RESULTS

A total of 151 articles were included in the analysis. Studies used several indicators to measure if individuals adhered to dietary guidelines. Traditional food consumption was frequently used as an indicator of diet quality (n = 96). The consumption of store-bought foods was used as an indicator in 28 studies. Some studies used other diet quality indicators such as the Healthy Eating Index (n = 5) and ultra-processed food "NOVA" classification (n = 6). A trend for decreasing traditional food intake over time was apparent, alongside an increase in store-bought food intake. This trend was accompanied with declining health status, including the increased prevalence of overweight and obesity, diabetes, metabolic diseases, and dental caries.

CONCLUSION

This scoping review showed that diet quality among First Nations is improved when traditional foods are consumed. Reduced diet quality was associated with increased risk of noncommunicable diseases.

What Is Wellbeing, and What Is Important for Wellbeing? Indigenous Voices from across Canada

Indigenous peoples' perceptions of wellbeing differ from non-Indigenous constructs. Thus, it is imperative to recognize that Indigenous peoples will conceptualize wellbeing from their perspectives and set their own wellbeing priorities. In keeping with this viewpoint, the aims of the present study were to conceptualize wellbeing and determine what was (and is) important for wellbeing from Canadian Indigenous peoples' perspectives. In this paper, we take a partnership approach based on the elements of respect, equity, and empowerment. One primary data source and two existing data sources were examined and analyzed thematically utilizing a combination approach of deductive and inductive coding. Indigenous leadership and organizations viewed wellbeing holistically and conceptualized wellbeing multidimensionally. From across Canada, wellbeing was communicated as physical, economic, political, social, and cultural. The scaling of wellbeing represented a collectivist perspective, and land was the connecting thread between all types of wellbeing, being a place to practice cultural traditions, reassert one's Indigenous identity, find solace, and pass on Indigenous knowledge and languages. Although wellbeing was discussed in the context of the individual, family, community, and nation, wellbeing was most often discussed at the cultural level by regional and national Indigenous leadership and organizations. Even in acknowledging the great cultural diversity among Canadian Indigenous nations, four concordant themes were identified regionally and nationally, with respect to what was important for cultural wellbeing: land and water, sustainability, and inherent obligations; being on the land, and indigenous languages and knowledge systems; sustainable development; and meaningful involvement in decision-making, and free, prior, and informed consent. Taking into account these themes is foundational for any interaction with Indigenous peoples, especially in the context of land, culture, and development. There needs to be a new beginning on the journey to reconciliation with land and cultural wellbeing at the forefront.

Visual Characteristics of Adults with Long-Standing History of Dietary Exposure to Mercury in Grassy Narrows First Nation, Canada

Since the 1960s, Grassy Narrows First Nation (Ontario, Canada) has been exposed to methyl mercury (Hg) through fish consumption, resulting from industrial pollution of their territorial waters. This cross-sectional study describes the visual characteristics of adults with documented Hg exposure between 1970 and 1997. Oculo-visual examinations of 80 community members included visual acuity, automated visual fields, optical coherence tomography [OCT], color vision and contrast sensitivity. Median age was 57 years (IQR 51-63) and 55% of participants were women. Median visual acuity was 0.1 logMAR (Snellen 6/6.4; IQR 0-0.2). A total of 26% of participants presented a Visual Field Index inferior to 62%, and qualitative losses assessment showed concentric constriction (18%), end-stage concentric loss (18%), and complex defects (24%). On OCT, retinal nerve fiber layer scans showed 74% of participants within normal/green range. For color testing with the Hardy, Rand, and Rittler test, 40% presented at least one type of color defect, and with the Lanthony D-15 test, median color confusion index was 1.59 (IQR 1.33-1.96). Contrast sensitivity showed moderate loss for 83% of participants. These findings demonstrate important loss of visual field, color vision, and contrast sensitivity in older adults in a context of long-term exposure to Hg in Grassy Narrows First Nation.

A probabilistic hazard and risk assessment of exposure to metals and organohalogens associated with a traditional diet in the Indigenous communities of Eeyou Istchee (northern Quebec, Canada)

Hunting, trapping, and fishing are part of an Indigenous lifestyle in subarctic Canada. However, this lifestyle may be a route of exposure to contaminants and may pose a risk for the people who rely on a subsistence diet. Monte Carlo simulations for the chemical concentration of eight game species and one fish species were carried out by randomly sampling 10,000 samples from the contaminant measures for each species. We then calculated a probabilistic non-carcinogenic hazard quotient or carcinogenic risk values to estimate the human health risk of exposure to contaminants. Of the species examined, ducks were of concern for potential carcinogenic risk. There was a modeled probabilistic 95th-percentile risk associated with the consumption of ducks and polybrominated biphenyl (PBB) congener 153 in boys, women, and men (1.09 × 10-6, 1.57 × 10-6, and 2.17 × 10-6, respectively) and, to a lesser extent, with geese and polychlorinated biphenyl (PCB) congener 153 in men (1.19 × 10-6). Contaminant concentration in the intake rate (food consumption) for PBB congener 153 exposure risk was more important than that for PCB congener 153, where intake rate had greater relevance. The consumption of waterfowl may increase the exposure to organohalogens; however, there are health and wellness benefits associated with the harvesting and consumption of subsistence foods that must also be considered. We recommend follow-up species-specific studies focused on ducks to clarify and elucidate the results in the present study.

Food Security Status of Indigenous Peoples in Canada According to the 4 Pillars of Food Security: A Scoping Review

Food insecurity is a significant public health problem for Indigenous peoples in Canada. A comprehensive literature review is needed to organize the evidence according to the 4 pillars of food security (i.e., availability, access, utilization, and stability) and identify gaps in the published literature on this topic. Therefore, in this scoping review we aimed to summarize the published research discussing any of the 4 pillars of food security among Indigenous peoples in Canada. We conducted a literature search of the following databases: Ovid Medline, EMBASE, Web of Science (Web of Knowledge), and CINAHL, as well as the Indigenous Studies Portal (up to June 19, 2021). Population-based studies of any design were included, except for review-style articles. Articles published in languages other than English were also excluded. Of the 4687 studies identified by the database searches, 91 met our inclusion criteria. Evidence from these studies indicates that all dimensions of food security among Indigenous peoples in Canada have been impacted. Lack of availability of both traditional and market foods is highlighted among Inuit and First Nation communities. Economic disadvantages, high food prices, and lack of access to transportation are major factors affecting the accessibility pillar of food security. Major factors affecting the utilization pillar of food security are the loss of traditional knowledge and skills, lack of knowledge on market foods, low quality of market foods, and food safety issues. Climate change has affected all 4 pillars of food security among Indigenous peoples. These findings suggest that resolving food insecurity issues among Indigenous peoples in Canada, especially those living in remote communities, requires a culturally specific integrated approach targeting food availability, food cost, food knowledge, food safety, and food quality.

A critical review on microbes-based treatment strategies for mitigation of toxic pollutants

Contamination of the environment through toxic pollutants poses a key risk to the environment due to irreversible environmental damage(s). Industrialization and urbanization produced harmful elements such as petrochemicals, agrochemicals, pharmaceuticals, nanomaterials, and herbicides that are intentionally or unintentionally released into the water system, threatening biodiversity, the health of animals, and humans. Heavy metals (HMs) in water, for example, can exist in a variety of forms that are inclined by climate features like the presence of various types of organic matter, pH, water system hardness, transformation, and bioavailability. Biological treatment is an important tool for removing toxic contaminants from the ecosystem, and it has piqued the concern of investigators over the centuries. In situ bioremediation such as biosparging, bioventing, biostimulation, bioaugmentation, and phytoremediation and ex-situ bioremediation includes composting, land farming, biopiles, and bioreactors. In the last few years, scientific understanding of microbial relations with particular chemicals has aided in the protection of the environment. Despite intensive studies being carried out on the mitigation of toxic pollutants, there have been limited efforts performed to discuss the solutions to tackle the limitations and approaches for the remediation of heavy metals holistically. This paper summarizes the risk assessment of HMs on aquatic creatures, the environment, humans, and animals. The content of this paper highlights the principles and limitations of microbial remediation to address the technological challenges. The coming prospect and tasks of evaluating the impact of different treatment skills for pollutant remediation have been reviewed in detail. Moreover, genetically engineered microbes have emerged as powerful bioremediation capabilities with significant potential for expelling toxic elements. With appropriate examples, current challenging issues and boundaries related to the deployment of genetically engineered microbes as bioremediation on polluted soils are emphasized.

Heavy Metals and Human Health: Possible Exposure Pathways and the Competition for Protein Binding Sites

Heavy metals enter the human body through the gastrointestinal tract, skin, or via inhalation. Toxic metals have proven to be a major threat to human health, mostly because of their ability to cause membrane and DNA damage, and to perturb protein function and enzyme activity. These metals disturb native proteins’ functions by binding to free thiols or other functional groups, catalyzing the oxidation of amino acid side chains, perturbing protein folding, and/or displacing essential metal ions in enzymes. The review shows the physiological and biochemical effects of selected toxic metals interactions with proteins and enzymes. As environmental contamination by heavy metals is one of the most significant global problems, some detoxification strategies are also mentioned.

The effects of mTOR or Vps34-mediated autophagy on methylmercury-induced neuronal apoptosis in rat cerebral cortex

Methylmercury (MeHg) is a environmental contaminant, which can induce neurotoxic effects. So far, the exact molecular mechanisms of autophagy and its effect on apoptosis in MeHg-induced neurotoxicity have not been elucidated. Here, rats were exposed to MeHg (4, 8, or 12 μmol/kg) for 4 weeks to evaluate the dose-effect relationship between MeHg and apoptosis, or autophagy in cerebral cortex. On this basis, rapamycin (Rapa) or 3-methyladenine (3-MA) was administrated to further explore the regulatory mechanisms of autophagy on MeHg-induced neuronal apoptosis. The pathological changes, autophagy or apoptosis levels, expression of autophagic or apoptotic-associated factors such as mTOR, S6K1, 4EBP1, Vps34, Beclin1, p62, LC3, Bcl-2/Bax, caspase, or MAPKs were investigated. Results showed that MeHg dose-dependently induced pathological changes in cerebral cortex, and the levels of autophagy and apoptosis were increased. Furthermore, Rapa pretreatment antagonized MeHg-induced apoptosis, whereas 3-MA further aggravated apoptosis, which were supported by findings that Rapa activated mTOR-mediated autophagy while 3-MA inhibited Vps34-related autophagy, further affect neuronal apoptosis through regulation of apoptotic factors mentioned above. In conclusion, the findings indicated that MeHg dose-dependently induced autophagy or apoptosis, and mTOR or Vps34 may play important roles in mediating autophagy, which further regulated apoptosis through MAPKs or mitochondrial apoptosis pathways.

Green Energy—Green for Whom? A Case Study of the Kabinakagami River Waterpower Project in Northern Canada

Green energy has become a term that heralds efforts of environmental conservation and protection worldwide; however, much of it is marred with questions of what it means to be green. More precisely, it has become a question of Green for whom? While many of the impacts of supposed green energy projects are local in their reach, some may be more regional in their scope, such as hydroelectric power. Hydroelectric power generation negatively impacts the environment and people who rely on the environment for sustenance, such as, Indigenous peoples of northern Canada. Taking into account their position with respect to the areas impacted by these green projects, many Indigenous peoples have voiced their concerns and doubts concerning green energy, which is purported to be a mode of energy production that champions the environment. The Kabinakagami River Waterpower Project serves as a case study for both the potential effects of the project and the different views associated with these endeavors. If nothing else, the accounts and testimonies found within shall stand as a testament to the hubris of calling an energy project green without properly assessing and considering the impacts. While these statements relate to the case presented, they also carry significance in the wider world due to the numerous Indigenous communities around the world that are having their spaces slowly being encroached upon in the name of sustainable growth, or green energy. This will especially be true in the post-COVID-19 period where green energy and a green economy are being touted as a way towards state and worldwide recovery.

Toxic Mechanisms of Five Heavy Metals: Mercury, Lead, Chromium, Cadmium, and Arsenic

The industrial activities of the last century have caused massive increases in human exposure to heavy metals. Mercury, lead, chromium, cadmium, and arsenic have been the most common heavy metals that induced human poisonings. Here, we reviewed the mechanistic action of these heavy metals according to the available animal and human studies. Acute or chronic poisonings may occur following exposure through water, air, and food. Bioaccumulation of these heavy metals leads to a diversity of toxic effects on a variety of body tissues and organs. Heavy metals disrupt cellular events including growth, proliferation, differentiation, damage-repairing processes, and apoptosis. Comparison of the mechanisms of action reveals similar pathways for these metals to induce toxicity including ROS generation, weakening of the antioxidant defense, enzyme inactivation, and oxidative stress. On the other hand, some of them have selective binding to specific macromolecules. The interaction of lead with aminolevulinic acid dehydratase and ferrochelatase is within this context. Reactions of other heavy metals with certain proteins were discussed as well. Some toxic metals including chromium, cadmium, and arsenic cause genomic instability. Defects in DNA repair following the induction of oxidative stress and DNA damage by the three metals have been considered as the cause of their carcinogenicity. Even with the current knowledge of hazards of heavy metals, the incidence of poisoning remains considerable and requires preventive and effective treatment. The application of chelation therapy for the management of metal poisoning could be another aspect of heavy metals to be reviewed in the future.

The self-reported behaviour of Iiyiyiu Aschii Cree and the worry about pollution from industrial and hydroelectric development in northern Quebec, Canada

Worry is influenced by environmental pollution and affects individual health and well-being; however, little is known about this association in Indigenous communities. Using logistic regression models, we examined self-reported responses among Cree adults to the question "Are you worried about the pollution of the environment (land, water or air) in Iiyiyiu Aschii?" to assess if increased worry was associated with proximity to industrial and hydroelectric development, whether increased worry was associated with self-reported behavioural changes of water consumption type in the community or bush, and days spent on-the-land. Proximity to multiple industrial and hydroelectric development sites was associated with increased worry about pollution. Notably, the decreased consumption of tap water in the community was significantly associated with increased worry, but time-on-the land was not. Overall, our study provides new findings concerning development in a Cree territory in northern Quebec, Canada, and the worry about pollution's association with self-reported behavioural changes.

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

BACKGROUND

Participation 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.

METHODS

Using 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.

RESULTS

Participants 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.

CONCLUSIONS

Our 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).

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.