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57 records – page 1 of 6.

Adapting to the Impacts of Climate Change on Food Security among Inuit in the Western Canadian Arctic.

https://arctichealth.org/en/permalink/ahliterature96217
Source
Ecohealth. 2010 Aug 3;
Publication Type
Article
Date
Aug-3-2010
Author
Sonia D Wesche
Hing Man Chan
Author Affiliation
Community Health Sciences, University of Northern British Columbia, 3333 University Way, Prince George, BC, V2N 4Z9, Canada.
Source
Ecohealth. 2010 Aug 3;
Date
Aug-3-2010
Language
English
Publication Type
Article
Abstract
This study examined critical impacts of climate change on Inuit diet and nutritional health in four Inuit communities in the Inuvialuit Settlement Region, Western Arctic, Canada. The first objective was to combine data from community observation studies and dietary interview studies to determine potential climate change impacts on nutritional quality. The second objective was to address the scale of data collection and/or availability to compare local versus regional trends, and identify implications for adaptation planning. Information was compiled from 5 reports (4 community reports and 1 synthesis report) of climate change observations, impacts and adaptations in 12 Inuit communities (2005-2006), and from a dietary report of food use from 18 Inuit communities (1997-2000). Changing access to, availability of, quality of, and ability to use traditional food resources has implications for quality of diet. Nutritional implications of lower traditional food use include likely reductions in iron, zinc, protein, vitamin D, and omega-3 fatty acids, among others. The vulnerability of each community to changing food security is differentially influenced by a range of factors, including current harvesting trends, levels of reliance on individual species, opportunities for access to other traditional food species, and exposure to climate change hazards. Understanding linkages between climate change and traditional food security provides a basis for strengthening adaptive capacity and determining effective adaptation options to respond to future change.
PubMed ID
20680394 View in PubMed
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Assessing determinants of maternal blood concentrations for persistent organic pollutants and metals in the eastern and western Canadian Arctic.

https://arctichealth.org/en/permalink/ahliterature262603
Source
Sci Total Environ. 2015 May 8;527-528C:150-158
Publication Type
Article
Date
May-8-2015
Author
Meredith S Curren
Chun Lei Liang
Karelyn Davis
Kami Kandola
Janet Brewster
Mary Potyrala
Hing Man Chan
Source
Sci Total Environ. 2015 May 8;527-528C:150-158
Date
May-8-2015
Language
English
Publication Type
Article
Abstract
Aboriginal peoples in the Canadian Arctic are exposed to persistent organic pollutants (POPs) and metals mainly through their consumption of a traditional diet of wildlife items. Recent studies indicate that many human chemical levels have decreased in the north, likely due to a combination of reduced global chemical emissions, dietary shifts, and risk mitigation efforts by local health authorities. Body burdens for chemicals in mothers can be further offset by breastfeeding, parity, and other maternal characteristics. We have assessed the impact of several dietary and maternal covariates following a decade of awareness of the contaminant issue in northern Canada, by performing multiple stepwise linear regression analyses from blood concentrations and demographic variables for 176 mothers recruited from Nunavut and the Northwest Territories during the period 2005-2007. A significant aboriginal group effect was observed for the modeled chemicals, except for lead and cadmium, after adjusting for covariates. Further, blood concentrations for POPs and metals were significantly associated with at least one covariate of older age, fewer months spent breastfeeding, more frequent eating of traditional foods, or smoking during pregnancy. Cadmium had the highest explained variance (72.5%) from just two significant covariates (current smoking status and parity). Although Inuit participants from the Northwest Territories consumed more traditional foods in general, Inuit participants from coastal communities in Nunavut continued to demonstrate higher adjusted blood concentrations for POPs and metals examined here. While this is due in part to a higher prevalence of marine mammals in the eastern Arctic diet, it is possible that other aboriginal group effects unrelated to diet may also contribute to elevated chemical body burdens in Canadian Arctic populations.
PubMed ID
25965033 View in PubMed
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Assessing risk of mercury exposure and nutritional benefits of consumption of caribou (Rangifer tarandus) in the Vuntut Gwitchin First Nation community of Old Crow, Yukon, Canada.

https://arctichealth.org/en/permalink/ahliterature101631
Source
Environ Res. 2011 Aug;111(6):881-7
Publication Type
Article
Date
Aug-2011
Author
Roseanne C Schuster
Mary Gamberg
Cindy Dickson
Hing Man Chan
Author Affiliation
Health Sciences, University of Northern British Columbia, 3333 University Way, Prince George, BC, Canada V2N 4Z9.
Source
Environ Res. 2011 Aug;111(6):881-7
Date
Aug-2011
Language
English
Publication Type
Article
Abstract
The contamination of traditional foods with chemical pollutants is a challenge to the food security of Aboriginal Peoples. Mercury levels are generally low in terrestrial animals; however renal mercury levels have been shown to change over time in the Porcupine Caribou Herd, the principal food source for the Vuntut Gwitchin First Nation of Old Crow in Yukon, Canada. Seventy-five Porcupine Caribou muscle, sixty-three kidney and three liver samples were analyzed for total mercury. Average concentrations were 0.003, 0.360 and 0.120mg/kg wet weight total mercury for muscle, kidney and liver, respectively. Consumption data of caribou muscle, kidney and liver were collected from twenty-six adults in Vuntut Gwitchin households. Women of child-bearing age (n=5) consumed a median of 71.5g/person/day of caribou muscle and 0.0g/person/day kidney but consumed no liver; median consumptions for all other adults (women aged 40+ and all men, n=21) were 75.8, 3.2 and 2.5g/person/day for meat, kidney and liver, respectively. Median dietary exposures to total mercury from caribou tissues were estimated to be 0.138µg/kg body weight for women of child-bearing age and 0.223µg/kg body weight for other adults. Caribou tissues were found to contribute high levels of important nutrients to the diet and pose minimal health risk from mercury exposure.
PubMed ID
21700277 View in PubMed
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Assessment of neurotoxic effects of mercury in beluga whales (Delphinapterus leucas), ringed seals (Pusa hispida), and polar bears (Ursus maritimus) from the Canadian Arctic.

https://arctichealth.org/en/permalink/ahliterature263598
Source
Sci Total Environ. 2015 Mar 15;509-510:237-47
Publication Type
Article
Date
Mar-15-2015
Author
Anke Krey
Sonja K Ostertag
Hing Man Chan
Source
Sci Total Environ. 2015 Mar 15;509-510:237-47
Date
Mar-15-2015
Language
English
Publication Type
Article
Keywords
Animals
Arctic Regions
Beluga Whale - physiology
Canada
Environmental monitoring
Mercury - toxicity
Nervous System - drug effects
Pinnipedia - physiology
Seals, Earless - physiology
Ursidae - physiology
Water Pollutants, Chemical - toxicity
Abstract
Marine mammals are indicator species of the Arctic ecosystem and an integral component of the traditional Inuit diet. The potential neurotoxic effects of increased mercury (Hg) in beluga whales (Delphinapterus leucas), ringed seals (Pusa hispida), and polar bears (Ursus maritimus) are not clear. We assessed the risk of Hg-associated neurotoxicity to these species by comparing their brain Hg concentrations with threshold concentrations for toxic endpoints detected in laboratory animals and field observations: clinical symptoms (>6.75 mg/kg wet weight (ww)), neuropathological signs (>4 mg/kg ww), neurochemical changes (>0.4 mg/kg ww), and neurobehavioral changes (>0.1mg/kg ww). The total Hg (THg) concentrations in the cerebellum and frontal lobe of ringed seals and polar bears were 3mg/kg ww. Our results suggest that brain THg levels in polar bears are below levels that induce neurobehavioral effects as reported in the literature, while THg concentrations in ringed seals are within the range that elicit neurobehavioral effects and individual ringed seals exceed the threshold for neurochemical changes. The relatively high THg concentration in beluga whales exceeds all of the neurotoxicity thresholds assessed. High brain selenium (Se):Hg molar ratios were observed in all three species, suggesting that Se could protect the animals from Hg-associated neurotoxicity. This assessment was limited by several factors that influence neurotoxic effects in animals, including: animal species; form of Hg in the brain; and interactions with modifiers of Hg-associated toxicity, such as Se. Comparing brain Hg concentrations in wildlife with concentrations of appropriate laboratory studies can be used as a tool for risk characterization of the neurotoxic effects of Hg in Arctic marine mammals.
PubMed ID
24958011 View in PubMed
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Association between environmental contaminants and health outcomes in indigenous populations of the Circumpolar North.

https://arctichealth.org/en/permalink/ahliterature258481
Source
Int J Circumpolar Health. 2014;73:25808
Publication Type
Article
Date
2014
Author
Kavita Singh
Peter Bjerregaard
Hing Man Chan
Author Affiliation
Department of Biology, University of Ottawa, Ottawa, ON, Canada.
Source
Int J Circumpolar Health. 2014;73:25808
Date
2014
Language
English
Publication Type
Article
Abstract
Since the 1990s, research has been carried out to monitor environmental contaminants and their effects on human health in the Arctic. Although evidence shows that Arctic indigenous peoples are exposed to higher levels of contaminants and do worse on several dimensions of health compared with other populations, the contribution of such exposures on adverse outcomes is unclear.
The purpose of this review is to provide a synopsis of the published epidemiological literature that has examined association between environmental contaminants and health outcomes in Arctic indigenous populations.
A literature search was conducted in OVID Medline (1946-January 2014) using search terms that combined concepts of contaminant and indigenous populations in the Arctic. No language or date restrictions were applied. The reference lists of review articles were hand-searched.
Of 559 citations, 60 studies were relevant. The studies fell under the following categories: paediatric (n=18), reproductive health (n=18), obstetrics and gynaecology (n=9), cardiology (n=7), bone health (n=2), oncology (n=2), endocrinology (n=2) and other (n=2). All studies, except one from Arctic Finland, were either from Nunavik or Greenland. Most studies assessed polychlorinated biphenyls (n=43) and organochlorine pesticides (n=29). Fewer studies examined heavy metals, perfluorinated compounds, or polybrominated diphenyl ethers. Details of study results for each health category are provided.
It is difficult to make conclusive statements about the effects of environmental contaminants on health due to mixed results, small number of studies and studies being restricted to a small number of regions. Meta-analytical synthesis of the evidence should be considered for priority contaminants and health outcomes. The following research gaps should be addressed in future studies: association of contaminants and health in other Arctic regions (i.e. Inuvialuit Settlement Region, Nunavut, Nunatsiavut, Alaska, European North and Russian North); assessment of contaminants on chronic diseases; inclusion of clinical endpoints in assessments; and assessment of the emerging contaminants of perfluorinated compounds and polybrominated diphenyl ethers.
PubMed ID
25491153 View in PubMed
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Association between fish consumption, dietary omega-3 fatty acids and persistent organic pollutants intake, and type 2 diabetes in 18 First Nations in Ontario, Canada.

https://arctichealth.org/en/permalink/ahliterature282399
Source
Environ Res. 2017 May 05;156:725-737
Publication Type
Article
Date
May-05-2017
Author
Lesya Marushka
Malek Batal
William David
Harold Schwartz
Amy Ing
Karen Fediuk
Donald Sharp
Andrew Black
Constantine Tikhonov
Hing Man Chan
Source
Environ Res. 2017 May 05;156:725-737
Date
May-05-2017
Language
English
Publication Type
Article
Abstract
First Nations (FNs) populations in Canada experience a disproportionally higher rate of obesity and type 2 diabetes (T2D) compared to the general population. Recent data suggest that a high consumption of fish may help prevent T2D. On the other hand, fish might also be a potential source of environmental contaminants which could potentially be a risk factor for T2D.
To investigate the potential associations between self-reported T2D and consumption of locally-harvested fish, dietary long-chain omega-3 fatty acids (n-3FAs) and persistent organic pollutants intake among adult FNs living on reserve in Ontario.
Data from the First Nations Food Nutrition and Environment Study, which included a cross-sectional study of 1429 Ontario FNs adults living in 18 communities across 4 ecozones in 2012 were analyzed. Social and lifestyle data were collected using household interviews. The consumption of locally-harvested fish was estimated using a traditional food frequency questionnaire along with portion size information obtained from 24hr recalls. Fish samples were analyzed for the presence of contaminants including dichlorodiphenyldichloroethylene (DDE) and polychlorinated biphenyls (PCBs). Dietary intakes of DDE and PCBs were estimated using community-specific levels of DDE/PCBs in fish species. Multiple logistic regression models adjusted for potential covariates including age, gender, body mass index, physical activity, total energy intake, smoking, and education were developed.
The prevalence of T2D in Ontario FNs was 24.4%. A significant positive association between fish consumption of one portion per week and more and T2D compared to no fish consumption was found (OR=2.5 (95% CI: 1.38-4.58). Dietary DDE and PCBs intake was positively associated with T2D (OR=1.09 (95%CI: 1.05-1.75) for DDE and OR=1.07 (95%CI: 1.004-1.27) for PCBs) per unit increase in DDE/PCBs while n-3-FAs intake, adjusted for DDE/PCBs intake, showed an inverse effect against T2D among older individuals (OR=0.86 (95% CI: 0.46-0.99).
Our results support previous findings that exposure to DDE and PCBs may increase the risk of T2D. Elevated levels of contaminants in fish may counteract with potentially beneficial effects of n-3FAs from fish consumption. However, the overall health benefits of high consumption of fish with a high n-3 FAs content may outweigh the adverse effect of contaminants.
PubMed ID
28482294 View in PubMed
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Association of blood polychlorinated biphenyls and cholesterol levels among Canadian Inuit.

https://arctichealth.org/en/permalink/ahliterature286489
Source
Environ Res. 2017 Oct 13;160:298-305
Publication Type
Article
Date
Oct-13-2017
Author
Kavita Singh
Hing Man Chan
Source
Environ Res. 2017 Oct 13;160:298-305
Date
Oct-13-2017
Language
English
Publication Type
Article
Abstract
It has generally been thought that Inuit populations have low risk of cardiovascular disease due to high consumption of omega-3 fatty acids found in traditional marine-based diets. However, results of recent surveys showed that Inuit populations are experiencing increasing rates of cardiovascular disease and related risk factors.
The purpose of this study was to investigate if blood polychlorinated biphenyls (PCBs) are associated with high cholesterol and related parameters in Canadian Inuit, known risk factors for cardiovascular disease.
The Adult Inuit Health Survey (IHS, 2007-2008) included 2595 Inuit participants from three regions of the Canadian Arctic, of which 2191 could be classified as with or without high cholesterol. The high cholesterol outcome was defined by LDL-C > 3.36mmol/L or taking medication(s) that reduce cholesterol, and was examined in adjusted logistic regression models with individual blood levels of PCB congeners, sum of dioxin-like PCBs (?DL-PCBs), or sum of non-dioxin-like PCBs (?NDL-PCBs). Statistically significant covariates for high cholesterol were ranked in importance according to the proportion of the model log likelihood explained. Continuous clinical parameters of total cholesterol, triglycerides, LDL-C, and HDL-C were examined in multiple linear regression models with ?DL-PCBs or ?NDL-PCBs.
A total of 719 participants had high cholesterol (32.8%). PCBs were associated with increased risk of high cholesterol, and higher levels of serum triglycerides, total cholesterol, and LDL-C. No association was observed between PCBs and serum HDL-C. With respect to other statistically significant covariates for high cholesterol, the log likelihood ranking of PCBs generally fell between body mass index (BMI) and age.
Further work is needed to corroborate the associations observed with PCBs and lipids in Canadian Inuit and to examine if they are causal in the direction anticipated.
PubMed ID
29035785 View in PubMed
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Balancing the benefits and costs of traditional food substitution by indigenous Arctic women of childbearing age: Impacts on persistent organic pollutant, mercury, and nutrient intakes.

https://arctichealth.org/en/permalink/ahliterature273769
Source
Environ Int. 2016 Jun 18;
Publication Type
Article
Date
Jun-18-2016
Author
Matthew J Binnington
Meredith S Curren
Hing Man Chan
Frank Wania
Source
Environ Int. 2016 Jun 18;
Date
Jun-18-2016
Language
English
Publication Type
Article
Abstract
For indigenous Arctic Canadians, traditional food consumption represents a key source of nutrients and environmental contaminants. Particularly, ingestion of marine mammal blubber and meat may lead to persistent organic pollutant levels and mercury intakes that exceed regulatory thresholds for sensitive populations. We investigated whether temporary adjustments to the consumption of traditional food derived from marine mammals appreciably impacted contaminant exposure and nutrient intakes among indigenous women of childbearing age. Such adjustments can be motivated by the desire to lower contaminant exposure or to increase nutrition, or by the diminishing availability of other traditional food sources. We combined the contaminant fate and transport model GloboPOP with the food chain bioaccumulation model ACC-Human Arctic to simulate polychlorinated biphenyl exposures in female 2007-08 Inuit Health Survey participants. We also calculated daily mercury and nutrient intake rates. Our results suggest that a temporary decrease in marine mammal consumption is largely ineffective at reducing exposure to polychlorinated biphenyls, because of their long elimination half-lives. In contrast, substitution of marine mammals was highly efficient at reducing mercury intake, but also appreciably lowered intakes of iron, manganese, selenium, and ?-3 polyunsaturated fatty acids. The impact of increasing intake of traditional food derived from marine mammals during childbearing age greatly depended on baseline consumption rates; replacement is ill-advised for those who already consume a lot of traditional food due to greater polychlorinated biphenyl and mercury exposures, while replacement was potentially beneficial for those with very limited marine mammal consumption due to increased nutrient intakes. Our calculations primarily suggest that considering baseline traditional food intake rates is critical to devising reproductive dietary adjustment strategies that maximize nutrient intake while minimizing environmental contaminant exposure.
PubMed ID
27329691 View in PubMed
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Balancing the benefits and costs of traditional food substitution by indigenous Arctic women of childbearing age: Impacts on persistent organic pollutant, mercury, and nutrient intakes.

https://arctichealth.org/en/permalink/ahliterature289991
Source
Environ Int. 2016 09; 94:554-566
Publication Type
Journal Article
Date
09-2016
Author
Matthew J Binnington
Meredith S Curren
Hing Man Chan
Frank Wania
Author Affiliation
Department of Physical and Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada.
Source
Environ Int. 2016 09; 94:554-566
Date
09-2016
Language
English
Publication Type
Journal Article
Keywords
Adult
Arctic Regions
Cost-Benefit Analysis
Diet - adverse effects - statistics & numerical data
Environmental Exposure - analysis - economics - statistics & numerical data
Environmental Pollutants - analysis
Female
Food chain
Humans
Indians, North American - statistics & numerical data
Polychlorinated biphenyls - analysis
Abstract
For indigenous Arctic Canadians, traditional food consumption represents a key source of nutrients and environmental contaminants. Particularly, ingestion of marine mammal blubber and meat may lead to persistent organic pollutant levels and mercury intakes that exceed regulatory thresholds for sensitive populations. We investigated whether temporary adjustments to the consumption of traditional food derived from marine mammals appreciably impacted contaminant exposure and nutrient intakes among indigenous women of childbearing age. Such adjustments can be motivated by the desire to lower contaminant exposure or to increase nutrition, or by the diminishing availability of other traditional food sources. We combined the contaminant fate and transport model GloboPOP with the food chain bioaccumulation model ACC-Human Arctic to simulate polychlorinated biphenyl exposures in female 2007-08 Inuit Health Survey participants. We also calculated daily mercury and nutrient intake rates. Our results suggest that a temporary decrease in marine mammal consumption is largely ineffective at reducing exposure to polychlorinated biphenyls, because of their long elimination half-lives. In contrast, substitution of marine mammals was highly efficient at reducing mercury intake, but also appreciably lowered intakes of iron, manganese, selenium, and ?-3 polyunsaturated fatty acids. The impact of increasing intake of traditional food derived from marine mammals during childbearing age greatly depended on baseline consumption rates; replacement is ill-advised for those who already consume a lot of traditional food due to greater polychlorinated biphenyl and mercury exposures, while replacement was potentially beneficial for those with very limited marine mammal consumption due to increased nutrient intakes. Our calculations primarily suggest that considering baseline traditional food intake rates is critical to devising reproductive dietary adjustment strategies that maximize nutrient intake while minimizing environmental contaminant exposure.
PubMed ID
27329691 View in PubMed
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Bioaccessibility of mercury from traditional northern country foods measured using an in vitro gastrointestinal model is independent of mercury concentration.

https://arctichealth.org/en/permalink/ahliterature148639
Source
Sci Total Environ. 2009 Nov 15;407(23):6003-8
Publication Type
Article
Date
Nov-15-2009
Author
Brian D Laird
Christopher Shade
Nikolaus Gantner
Hing Man Chan
Steven D Siciliano
Author Affiliation
Graduate Program of Toxicology, University of Saskatchewan, Saskatoon, SK, Canada.
Source
Sci Total Environ. 2009 Nov 15;407(23):6003-8
Date
Nov-15-2009
Language
English
Publication Type
Article
Keywords
Animals
Biological Availability
Canada
Environmental Exposure
Food analysis
Humans
Mercury - analysis - pharmacokinetics
Models, Biological
Risk assessment
Species Specificity
Abstract
Human health risk assessment of dietary mercury (Hg) exposure in Canada assumes that all Hg from fish consumption is in the form of methylmercury (MeHg), the more bioavailable and hazardous form of Hg. In contrast, the risk assessment of dietary Hg to Inuit in northern Canada assumes that no more than two-thirds of dietary Hg is MeHg since mammal organs consumed by Inuit contain substantial concentrations of inorganic Hg. In vitro gastrointestinal models (e.g., the Simulator of the Human Intestinal Microbial Ecosystem) are often used for the evaluation of soil contaminant bioaccessibility, i.e., the fraction solubilized into gastrointestinal fluids, for use in site-specific human health risk assessment. In this research, we digested northern country foods using the SHIME for the measurement of Hg bioaccessibility, a novel approach for the assessment of dietary Hg bioavailability. We demonstrated that small intestinal Hg bioaccessibility from 16 fish, wild game, and marine mammal samples consumed by Inuit in northern Canada ranged between 1 and 93% and was independent of food HgT (MeHg+Hg(II)) concentration. Additionally, we demonstrated that gastrointestinal microbes may affect Hg bioaccessibility of the 16 country foods, either increasing or decreasing bioaccessibility depending upon the type of food. These results indicate that gastrointestinal absorption of Hg is not likely limited by the concentration of Hg in the food, which is in agreement with in vivo Hg bioavailability studies. Furthermore, these in vitro results support the hypothesis that the gastrointestinal absorption of Hg from Inuit country foods is dependent upon food type.
PubMed ID
19740524 View in PubMed
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57 records – page 1 of 6.