Blood and hair mercury concentrations among Cree First Nations of Eeyou Istchee (Quebec, Canada): time trends, prenatal exposure and links to local fish consumption

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.

Indigenous maternal health and health services within Canada: a scoping review

BACKGROUND

Globally, there are disparities in access to maternal health care services and equity in maternal health outcomes between Indigenous and non-Indigenous populations. While the literature is growing, it has not been systematically synthesized. This review addresses this gap by synthesizing the existing literature on the organizational structure of maternity care, accessibility and delivery of services, and clinical disparities impacting Indigenous maternal health within Canada. It also identifies current knowledge gaps in research on these topics.

METHODS

A scoping review was completed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement guidelines and the extension for scoping reviews. The search for relevant papers was performed in PubMed, CINAHL, and SCOPUS electronic databases and included any empirical literature written in English and published during 2006 - 2021. The research team inductively coded 5 articles to develop a coding scheme, which was then applied to the remaining articles.

RESULTS

A total of 89 articles were included in the review, of which 32 were qualitative papers, 40 quantitative, 8 were mixed-methods publications, and 9 were review papers. The analysis of the articles resulted in identifying a range of overarching themes pertaining to the maternal health of Indigenous women within Canada including provision of services, clinical issues, education, health disparities, organization, spatial context, and impact of informal support. The results suggest that physical, psychological, organizational, and systemic barriers inhibit the quality-of-care pregnant Indigenous women receive, and that maternal health services are not consistently provided in a culturally safe manner. Results also suggest that, compared to non-Indigenous pregnant women, Indigenous women are more likely to develop clinical complications during pregnancy, reflecting the structural impacts of colonization that continue to negatively influence Indigenous maternal health and well-being.

CONCLUSIONS

There are many complex barriers that prevent Indigenous women from receiving high quality and culturally appropriate maternal care. Possible areas that could address the service gaps illuminated through this review include the implementation of cultural considerations across health care jurisdictions within Canada.

Sustainable or Not? Insights on the Consumption of Animal Products in Poland

Animal products are one of the main constituents of the human diet. They are the main source of energy, proteins, microelements, and bioactive substances. The most popular negative health impacts linked with the consumption of animal products are obesity, atherosclerosis, heart attacks, and cancer. Apart from human health, consuming animal products is also controversial lately, due to farm animals' well-being and environmental protection issues. Thus, within the context of sustainability, the consumption trends of animal products were investigated through our on-line questionnaire surveys. The following animal products were involved in the survey: unprocessed meat (pork, beef, lamb, veal, mutton, chicken, duck, goose, turkey), processed meat (cold-cuts, sausages, pates), fish products, and eggs. Our research concluded that consumption among respondents with higher education was unsustainable for both unprocessed and processed meat, as eating habits in terms of type and quantity of consumed meat indicated respondents' unawareness. The consumption of fish products was also revealed as unsustainable regarding the quantity of fish consumed in terms of its beneficial nutritional values. Egg consumption was revealed as the most sustainable among the investigated animal products. However, insignificant egg consumption among the respondents showed the actual need of social education in terms of the current knowledge regarding the beneficial aspects of eggs.

High variability of mercury content in the hair of Russia Northwest population: the role of the environment and social factors

PURPOSE

The purpose of this work is to study mercury levels in the hair of different social and demographic groups of the population of the Vologda region in Northwest Russia. This region is selected due to a heterogeneous distribution of rivers and lakes-a resource base for fishing.

METHODS

The mercury content was determined in the hair from the root with a length of about 2 cm. The concentration of total mercury in human hair was determined by the atomic absorption method without preliminary sample preparation using an RA-915M mercury analyzer and a PYRO-915 + pyrolysis unit.

RESULTS

The average level of mercury in the human hair was 0.445 μg/g (median 0.220 μg/g). The concentration of mercury in the hair of people older than 44 years (0.875 μg/g) was three times higher than in the hair of children under 18 years of age (0.270 μg/g). People who eat fish less than once per month had a hair mercury concentration of 0.172 μg/g, for 1-2 times a month 0.409 μg/g, once a week 0.555 μg/g, and several times a week 0.995 μg/g. The concentration of mercury in the hair of smokers (0.514 μg/g) was higher than in the hair of non-smokers (0.426 μg/g).

CONCLUSION

Significantly higher concentrations of mercury were observed in the hair of participants from the western part of the region, where reservoirs are the main commercial sources of fish products. The data showed that the main source of people's mercury intake was fish.

Food frequency questionnaire assessing traditional food consumption in Dene/Métis communities, Northwest Territories, Canada

Food Frequency Questionnaires (FFQ) can be used to document food consumption and to estimate the intake of contaminants for Indigenous populations. The objective of this project was to refine and implement an FFQ to estimate the consumption of traditional locally harvested foods for Dene/Métis in the Northwest Territories, Canada. The strategy consisted of: 1) refining the FFQ through three focus groups and, 2) implementing the FFQ in Indigenous communities. Participants were asked to complete the FFQ using an iPad to document the types of traditional foods consumed over the past 12 months, as well as the consumption frequency, the portion size, and the preparation methods. Focus groups supported the refinement of the FFQ on the format, the list of foods, and the preparation methods listed in the questionnaire. The refined FFQ was then implemented with participants (n = 237). Findings indicated that the traditional foods most frequently consumed were moose, whitefish and lake trout. Participants who consumed fish and land animals reported, on average, a portion size for one serving of between 126 and 143 g, depending on age and sex. These findings increase knowledge of the current traditional food consumption of Dene/Métis communities and will support the assessment of contaminant exposure.

Temporal variation of total mercury levels in the hair of pregnant women from the Maternal-Infant Research on Environmental Chemicals (MIREC) study

Prenatal exposure to total mercury (T-Hg) comes from both natural and anthropogenic sources. T-Hg can cross the blood-brain and placental barriers, and may be associated with future neurological and physiological dysfunctions. Scalp hair is an optimal and non-invasive indicator of chronic T-Hg exposure. As part of the Maternal-Infant Research on Environmental Chemicals (MIREC) Study, hair samples from 350 women were collected within weeks after giving birth, to determine temporal variations in T-Hg levels from preconception to delivery, and to compare these levels to corresponding levels measured in other matrices (maternal and umbilical cord blood, and infant's meconium). A maximum of 12 one-cm hair segments were cut starting at the scalp; segments closer to the scalp reflected recent exposure (within the last month). For proper comparison, the hair segments were matched with the collection dates for other matrices. GM hair T-Hg levels greatly decreased during pregnancy, from 0.26 μg g^-1 (preconception or full-length hair) to 0.18 μg g^-1 (at delivery or segments closer to the scalp). A similar decreasing trend was found for T-Hg in maternal blood: 1st trimester (0.60 μg L^-1) to 3rd trimester (0.47 μg L^-1). The median hair-to-blood ratios of T-Hg levels varied from 364 (1st trimester), to 408 (3rd trimester), to 229 (cord blood). Very low T-Hg levels were detected in meconium. Mercury levels in blood and hair correlated with consumption of large predatory fish.

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 (R²_A = 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.

Microelement composition of serum in Dolgans, indigenous inhabitants of the Russian Arctic, in the conditions of industrial development of territories

The geochemical conditions of landscapes are the content in the environment of certain chemical elements and their compounds, the lack or excess of which causes deviations in the state of human health. This problem has arisen in connection with the extraction of alluvial diamonds and the forthcoming development of the Tomtor deposit of rare-earth metals in the territories where the indigenous peoples of the North live. The study included 107 indigenous people of the North, belonging to the ethnic group of Dolgans living in the village of Yuryung-Khaya, Anabar district, Yakutia of Russia. The method of mass spectrometry was used to study the content of 13 trace elements in blood serum (P, Sc, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Rb, Sr, Cs, Pb). The study revealed an increase in the content of the macroelement phosphorus (148 mg/L) and trace elements of chromium (277 μg/L), manganese (133 μg/L), iron (5219 μg/L), nickel (57 μg/L) in serum of Dolgans, which may affect the development of diseases of the cardiovascular system and other diseases among indigenous inhabitants of the Arctic under conditions of industrial development of territories.

Environmental mercury exposure and selenium-associated biomarkers of antioxidant status at molecular and biochemical level. A short-term intervention study

Mercury (Hg) is a potent toxicant. In the field of public health a chronic-low-level environmental Hg exposure resulting from fish consumption in general population is still being discussed. The objective of the study was to assess the influence of real Hg exposure on biomarkers of selenium (Se) status and selected biomarkers of pro-oxidant/anti-oxidant effects in healthy men (n = 67) who participated in the short-term intervention study consisting in daily fish consumption for two weeks. The analysis included Se level, Se-associated antioxidants at molecular (profile of 7 genes encoding selected proteins related to antioxidant defense) and biochemical levels (Se-dependent glutathione peroxidases activities and plasma selenoprotein P concentration). A pro-oxidant/anti-oxidant balance was explored using a biomarker of plasma lipid peroxidation and total antioxidant activity. The study revealed significant correlations (p < 0.05) between the biomarkers of exposure to Hg, Se level and Se-dependent antioxidants. Even though the risk of adverse effects of Hg for volunteers was substantially low, biomarkers of Hg altered levels of circulation selenoproteins and their genes expression. Changes in genes expression during study differed between the main enzymes involved in two systems: downregulation of thioredoxin reductase1 and upregulation of glutathione peroxidases. Hg exposure caused imbalance between the biomarkers of pro-oxidant/anti-oxidant effects.

Biomonitoring programs in Michigan, Minnesota and New York to assess human exposure to Great Lakes contaminants

Over the past century, industrialization and urban practices have resulted in the contamination of the Great Lakes ecosystem-the world's largest surface freshwater system-that provides drinking water and recreation to more than 40 million residents. In 2010, the Great Lakes Restoration Initiative was launched to accelerate efforts to protect and restore the Great Lakes and surrounding areas. Funded by GLRI, the Agency for Toxic Substances and Disease Registry initiated the Biomonitoring of Great Lakes Populations (BGLP) program. The objective of the program is to assess human exposure to legacy and emerging contaminants in the Great Lakes by measuring the body burden of contaminants in potentially susceptible populations. The BGLP program consists of a series of cross-sectional studies carried out collaboratively with states that are funded through ATSDR. The first BGLP Program (BGLP-I) began in 2010 and was completed in September 2015 through cooperative agreements with state health departments in Michigan, Minnesota, and New York. The three state programs targeted susceptible adult populations living in designated areas of contamination. Contaminants measured in all populations include mercury, lead, mirex, hexachlorobenzene, dichlorodiphenyltrichloroethane, and selected polychlorinated biphenyl congeners. In addition, some chemicals of emerging concern, such as per- and polyfluoroalkyl substances, were measured in several populations. The biomonitoring results helped guide public health actions to mitigate chemical exposures in these vulnerable Great Lakes populations. We provide an overview of the BGLP-I program's study populations, designs, and general methods. This overview provides a lead-in for subsequent manuscripts that present human biomonitoring data for legacy and emerging contaminants in culturally diverse susceptible populations-i.e., shoreline anglers, sport anglers, American Indians, and Burmese immigrants-residing in seven areas of concern.