Human Health (2016-2017)

Table of Contents

Assessment of contaminant and dietary nutrient interactions in the Inuit Health Survey: Nunavut, Nunatsiavut and Inuvialuit

Project Leader: Laurie Chan, Center for Advanced Research in Environmental Genomics, University of Ottawa
Tel: (613) 562-5800 ext 6349; Fax: (613) 562-5385
Email: laurie.chan@uottawa.ca

Project Team:

  • Brian Laird, University of Ottawa;
  • Kue Young, University of Toronto;
  • Geraldine Osborne and Maureen Baikie, Office of the Chief Medical Officer of Health, Government of Nunavut;
  • Sharon Edmunds-Potvin, Nunavut Tunngavik Inc.;
  • Eric Dewailly and Pierre Ayotte, Université Laval;
  • Chris Furgal and Amanda Boyd, Trent University

Northern Regions Included in the Study: Nunavut, Nunatsiavut and Inuvialuit

Project Duration: 2011-2014

Project Summary (2013-2014)

The Inuit Health Survey (IHS) is a major study that provides a snapshot and baseline data on the health status of Inuit across the North for the first time. This project is a component of the Inuit Health Survey focusing on contaminant levels in humans and country foods. In 2013-2014, the work focuses on: 1) data analysis on the relationship between contaminant exposure and chronic diseases and food security, 2) follow up survey on the response to the public health messages and risk perception of the residents in 3 communities in Nunavut, 3) developing a common platform for data sharing/analysis for IHS and data collected from Nunavik and Greenland, 4) follow up consultation and communication with the IHS national steering committee. Results describing the body burden and estimated dietary intake of contaminants were reported to each of the 3 regional steering committees in 2011 and key results/messages were presented in community reports and released in each of the 3 regions 2012. This will be the final year of the project. Results of the study will provide useful information to assist health professionals and policy makers at the regional, provincial, territorial, national, and international levels in developing environmental health policies and aid Inuit in making informed dietary choices.

Synopsis (2012-2013):

The Assessment of contaminant and dietary nutrient interactions in the Inuit Health Survey seeks to incorporate contaminants research within the context of a broader health research study conducted in Nunavut, Nunatsiavut and Inuvialuit in 2007-2008. This report presented key results on (1) the relationship between esterase paraoxonase (PON1), a major component of high-density lipoprotein (HDL), and the intake of traditional food and body burden of contaminants, (2) the communications activities of the contaminant results, and (3) progress of the risk perception study conducted in Nunavut. PON1 activity and metal concentrations were measured in blood collected from 2172 healthy participants. Sociodemographic, anthropometric and lifestyle variables were also assessed. The associations between PON1 activity and blood metal concentrations, age, sex, body mass index (BMI), and lifestyle habits (eg. smoking and alcohol consumption) were explored via multiple linear regression. PON1 activity was positively associated with Se blood concentration and n-3 fatty acids in the red blood cells but was negatively associated with Cd blood concentration. No association was observed between PON1 activity and Hg or Pb blood concentrations. Our results suggest that: PON1 activity is modulated by metal exposure, and Inuit traditional foods may confer health benefit by increasing PON1 activity via higher Se and n-3 fatty acids intake rates. These findings underline the importance of considering the nutritional benefits conferred by traditional foods when developing food consumption advisories to limit people’s intake of contaminants. Key results/ messages from this study were presented in 3 regional reports published and released in June 2012 and a dietary advisory was issued in Nunavut. The perception of contaminants was assessed by interviewing 545 participants in 3 communities in Nunavut in February/ March 2013. Results of the study will provide useful information to assist health professionals and policy makers at the regional, provincial, territorial, national, and international levels in developing environmental health policies and aid Inuit in making informed dietary choices.

Key Messages

  • Country foods provide many essential nutrients that can lower the risk of chronic diseases.
  • Generally, the benefits of eating country foods outweigh the risks from contaminant exposure.
  • Inuit women of child-bearing age in Nunavut who may become pregnant, are planning to get pregnant, or are pregnant should avoid eating ringed seal liver due to its high mercury content. Instead, ringed seal meat is a great and healthy alternative.
  • Smoking is a major problem for many reasons. One such reason is that smoking exposes Inuit to high levels of cadmium.



Synopsis (2011-2012):

Abstract
The Assessment of contaminant and dietary nutrient interactions in the Inuit Health Survey seeks to incorporate contaminants research within the context of a broader health research study conducted in Nunavut, Nunatsiavut and Inuvialuit in 2007-8. This report presented key results on (1) the country food sources of contaminant exposure, (2) the percentage of participants that meet nutrient Dietary Reference Intake (DRI) and contaminant Toxicological Reference Values (TRV), and (3) options that maximize nutrient intake while minimizing contaminant exposure. Estimated dietary intake of mercury (Hg), selenium (Se), polysatuarated fatty acids (PUFA) including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were significantly correlated with their respective concentrations in blood collected from study participants. Average Hg exposure (7.9 μg/kg/wk) exceeded the TRV of 5.0 μg/kg/wk with 35% of the population above this guideline. Average intakes for EPA and DHA met suggested dietary targets and average Se intakes fell within its Acceptable Range of Oral Intake (AROI). Since the estimated intakes of each of these nutrients were strongly correlated with estimated mercury exposure, efforts to decrease Hg exposure must emphasize the overall healthfulness of country foods and be designed to prevent concomitant harm to the nutrient status of Inuit.

Key Messages

  • The types of country foods consumed varied between the three participating regions
  • Exposure levels and the major Hg and nutrient contributors also differed between regions
  • Blood concentrations of Hg, Se, EPA and DHA were correlated with the estimated dietary intake
  • Dietary advice to lower contaminant intake must consider impacts on nutrient intake
  • Substitution of ringed seal liver with ringed seal meat is one possible strategy that decreases Hg intake without adversely affecting the nutrient status
 

top of page

Nunavik Child Cohort Study (NCCS): follow-up with late adolescents

Project Leader: Gina Muckle, Centre de recherche du CHU de Québec; Université Laval
Email: Gina.Muckle@crchul.ulaval.ca

Project Team:

  • Joseph L Jacobson and Sandra W. Jacobson, Wayne State University;
  • Éric Dewailly, Centre de Recherche du Centre Hospitalier Universitaire de Québec;
  • Pierre Ayotte,CR-CHU and INSPQ;
  • Richard Bélanger, CRCHUQ, Université Laval;
  • Pierrich Plusquellec, CRCHUQ, Université de Sherbrooke

Northern Regions Included in the Study: Nunavik

Project Duration: 2011-2014

Project Summary (2013-2014)

Prenatal exposure to Polychlorinated Biphenyls (PCBs) and mercury have been associated with growth and effects on cognitive development in children. The Inuit from Nunavik are exposed to these environmental pollutants as they accumulate in fish and marine mammals. However, consumption of fish and marine mammals also provides nutrients such as omega-3 fatty acids, which are known to enhance early brain development. There have been four studies conducted in Nunavik over the last 20 years: monitoring of prenatal exposure from cord blood sampling, an effect study with infants up to twelve months of age, and an effect study at preschool age. In 2010, the project team completed the follow-up of 294 eleven year-old children and, during the years 2010 and 2011, most of the eleven-year old data was analyzed. In fall 2011, the study results were presented to the Nunavik population and public health recommendations provided by the Public Health Director of Nunavik. Last year, the project team launched the follow-up of the cohort at adolescence and during the current year will continue this work and recruit 66 additional adolescents.

Synopsis (2012-2013):

Prenatal exposure to PCBs and mercury were associated with growth and effects on cognitive development in children. The Inuit from Nunavik are among the populations most highly exposed to these environmental pollutants due to their bioaccumulation in fish and marine mammals, which are consumed by the Inuit. However, consumption of fish and marine mammals also provides nutrients such as omega-3 fatty acids, which are known to enhance early brain development. We have conducted four studies in Nunavik over the last 20 years: monitoring of prenatal exposure from cord blood sampling, an effect study with infants up to 12 months of age, and an effect study at preschool age. In 2010, we completed the follow-up of 294 11 year-old children and, during the years 2010 and 2011, we analyzed most of the 11-year data. In fall 2011, study results were presented to the Nunavik population and public health recommendations were provided by the Public Health Director of Nunavik. Summary of study results and public health recommendations can be found at https://nrbhss.ca/. During the years 2011 and 2012, we completed the knowledge transfer activities, communicated the final study results to the Nunavik population and stakeholders and completed the analyses of the 11-year data. In 2012-2013, we launched the follow-up of the cohort at adolescence. We successfully pre-tested the research procedures and selected tests/instruments, and recruited and tested 61 adolescents aged between 16 and 19 years old living in communities located in Ungava Bay Coast. For 2013-2014, we are proposing to continue this work and recruit 66 additional adolescents living in communities from the Hudson Bay Coast.

Key Messages

  • The first data collection trip was completed in Kuujjuaq (Jan 25 to Feb 22 2013) with 61 participants successfully tested.
  • We obtain additional support from these Nunavik organizations: Nunavik Nutrition and Health Committee; Board of the Kativik Regional Government; Inuit Circumpolar Council –Canada Office; Municipal council of Kuujjuaq; Executive Board of the Nunavik Regional Board of Health and Social Services; Director of Tulattavik Health Center.
  • We obtained an additional grant for funding the research activities to be held during 2012/2013 from the Canadian Institutes of Health Research

Synopsis (2011-2012):

Abstract
Prenatal Exposure to PCBs and mercury were associated with growth and effects on cognitive development in children. The Inuit from Nunavik are among the populations most highly exposed to these environmental pollutants due to their bioaccumulation in fish and marine mammals. However, consumption of fish and marine mammals also provides nutrients such as omega-3 fatty acids, which are known to enhance early brain development. We have conducted four studies in Nunavik over the last 18 years: monitoring of prenatal exposure from cord blood sampling, an effect study with infants up to 12 months of age, and an effect study at preschool age (5 years). In 2010, we completed the follow-up of 294 school-age (11 years) children and, during the year 2010/2011, we analyzed most of the 11-year data, presented the results to a working group (WG) involving the Public Health Director of Nunavik (PHD), members of the Nunavik Nutrition and Health Committee (NNHC) and the researchers, and developed the messages and a communication plan for dissemination of study results in Nunavik. During the year 2011/2012 we completed the knowledge transfer activities, communicated the study results to the Nunavik population and stakeholders and completed the analyses of the 11-year data.

Key Messages

  • After one year of intensive knowledge transfer activities, the communication campaign aimed to provide results from the NCCS took place in Nunavik the week of October 3rd, 2011.
  • Dissemination of study results and public health recommendation to the Nunavik population was accomplished through various means. These included public meetings, radio shows, web sites, a letter mailed to each study participant, posting of project posters, distribution of a plain language fact sheet, a press release and recording of five YouTube videos.
  • This follow-up at age 11 successfully advanced our understanding of the domains affected by exposure to PCBs, mercury and lead, and provided new insights on the long-term beneficial effects of omega-3 fatty acids.
 

top of page

Environmental contaminants, stress and behaviour: statistical analysis in late-adolescent Inuit from the Nunavik Child Cohort Study (NCCS), and in adult Inuit from the Inuit Health Survey

Project Leader(s):

Pierrich Plusquellec, PhD, Centre de recherche de l’institut Universitaire en Santé Mentale de Montréal, Tel : (514) 251-4000 poste 3250, Fax: (514) 251-7968

Email : pierrich.plusquellec@umontreal.ca

Project Team:

Gina Muckle PhD, Éric Dewailly MD PhD, Pierre Ayotte PhD, Centre de recherche du CHUQ, Université Laval; Sonia Lupien PhD, Centre de Recherche IUSMM, Université de Montréal

Northern Regions Included in the Study: Nunavik

Project Duration: 2012-2015

2014-15

Abstract:

Prenatal exposure to lead, PCBs and mercury were associated to behavioural impairments in children. In the last three cohort studies conducted in Nunavik (1 year-old, 5 years-old, 11-years-old), we have assessed behavioural indicators at each stage of development and found subtle effects of lead on attention, activity, impulsivity, but also of PCBs on emotional outcomes. Although we continue to look at the association between environmental contaminants and those behavioural indicators, we have also focused on emotional outcomes, mainly stress. This focus on the stress system is based on recent scientific results showing that exposure to environmental contaminants may impair this endocrine system, and thus impact behavioural outcomes. Furthermore, adolescence is a period at which mechanisms of hormone disruption by environmental contaminants become obvious, and at which emotional development is particularly at risk. Finally, stress is a significant risk factor of attention, activity, impulsivity levels but also of various physical and mental disorders in adolescents. For the last 2 years (2012 to 2014), we have collected data on stress (cortisol levels in saliva, n=132 and in hair samples, n=99) and on behavioural dimensions (analysis of video recordings, n=77) from the follow-up study of children at age 17 leaded by Dr. Gina Muckle. A database has been created, checked, and is currently being merged with Dr. Muckle’s dataset. Results showed high variability between individuals, and associations between physiological outcomes of stress and behavioural indicators. In addition, work on the association between environmental contaminants was going on using data collected in 5 year-olds, and using data from the Inuit Health Survey.

Key messages:

  • Data collection of bio-indicators for the assessment of the stress system is feasible, and inter-individual variability in the value of these bio-indicators indicate that it is relevant to the Inuit population
  • Inter-individual variability in the value of behavioural dimensions following behavioural coding of video indicate that this way to assess attention, and emotional reactivity is still relevant in Inuit teenagers
  • Descriptive analyses of the bio-indicators of stress, and the behavioral indicators suggest an association between both
  • Analyses on data from 5 year-old children dataset have shown that there are postnatal windows of development during which children are more susceptible to neurotoxicants like PCBs
  • Analyses on data from the Inuit Health survey suggest that chronic stress could be associated with exposure to environmental contaminants, particularly in Inuit adults from 25-54 years of age

Project Summary (2013-2014)

Prenatal exposure to lead, Polychlorinated Biphenyls (PCBs) and mercury have been associated with behavioural impairment in children. In the last three cohort studies conducted in Nunavik (one year-old, five years-old, eleven-years-old), the project team has assessed behavioural development and found subtle effects of lead on attention, activity, impulsivity, but also of PCBs on emotional outcomes. For year 2013/2014, the project team is proposing an add-on study to the main follow-up of children at age seventeen. Adolescence is a period during which hormone disruption by environmental contaminants becomes obvious, and at which emotional development is particularly at risk. The project focuses on the assessment of observational data on attention, activity and emotional reactivity since those data have been shown to be highly sensitive to environmental contaminants exposure. Furthermore, the project team will focus on the assessment of the endocrine stress system. This focus on the stress system is based on recent scientific results showing that exposure to environmental contaminants may impair the endocrine system, and thus impact behavioural outcomes. Finally, data analysis from the Inuit Health Survey is included in this project in order to document associations between environmental contaminants and a physiological index of chronic stress.

Synopsis (2012-2013):

Prenatal exposure to lead, PCBs and mercury were associated to behavioural impairments in children. In the last three cohort studies conducted in Nunavik (1 year-old, 5 years-old, 11-years-old), we have assessed behavioural development and found subtle effects of lead on attention, activity, impulsivity, but also of PCBs on emotional outcomes. For year 2012/2013, we have proposed an add-on study to the main follow-up of children at age 17 proposed by G Muckle. Adolescence is thus a period at which mechanisms of hormone disruption by environmental contaminants become obvious, and at which emotional development is particularly at risk. Our project focuses on the assessment of observational data on attention, activity and emotional reactivity obtained from coding of videotapes since those data have been shown to be highly sensitive to environmental contaminants exposure. Furthermore, this project focus on the assessment of the endocrine stress system through a self-report questionnaire, saliva samples and hair sample to assess reactive glucocorticoids levels following the testing situation, and chronic stress. This focus on the stress system is based on recent scientific results showing that exposure to environmental contaminants may impair this endocrine system, and thus impact behavioural outcomes. Data collection on Inuit adolescents from 17 year-olds was realised during Winter 2013. Therefore, results are not yet available for these participants because behavioural observations as well as environmental contaminants and glucocorticoids levels are currently under analysis. Nonetheless, we pursue our analysis of children cohorts. In the 11 year-old children, results showed that postnatal exposure to Pb was still associated with increased activity and increased inattention, and also that prenatal exposure to PCBs was still related to increased negative affect during the blood test situation. In addition, we begin the analysis of the Nunavik Inuit Health Survey involving Inuit adults. Preliminary results suggest significant associations between increased exposure to 3 toxic metals (Pb, Hg, Cd) or 8 persistent organic pollutants (PCB 153, p,p’-DDE, trans-nonachlor, oxchlordane, PBDE 47, PFOS, PCP and toxaphene) and allostatic load, a validated indicator of chronic stress. These results indicate that exposure to environmental contaminants may trigger the chronic stress that leads to behavioural and psychological outcomes, as hypothesized.

Key Messages

  • Associations found between environmental contaminants and behavioral development are subclinical. It means that it does not impact the day to day functioning of Inuit children, but it prevents Inuit children from expressing their full potential of behavioral development. Those adverse associations were still measurable at 11 years of age.
  • In Inuit adults, preliminary results suggested that increased exposure to 3 toxic metals (Pb, Hg, Cd) or 8 persistent organic pollutants (PCB 153, p,p’-DDE, trans-nonachlor, oxchlordane, PBDE 47, PFOS, PCP and toxaphene) may be significantly associated with chronic stress.
  • The data collection for the ongoing study has been launched in February 2013 and to date, 58 Nunavik teenagers have been launched in February 2013 and to date, 58 Nunavik teenagers have been successfully tested at 17 years of age.
 

top of page

Contaminant Nutrient Interaction Issues as Part of a Public Health Intervention Study of Inuit Children in Nunavik: Communication of Results

Project Leader: Huguette Turgeon O ’Brien, Université Laval, Québec City
E-mail:huguette.turgeon-obrien@fsaa.ulaval.ca

Project Team:

  • Julie Lauzière and Annie Bédard, Université Laval;
  • Pierre Ayotte, (CHUQ).

Northern Regions Included in the Study: Nunavik

Project Duration: 2011-2014

Project Summary (2013-2014)

As part of a broader project called the Nutrition Program in Nunavik Childcare Centres, this study primarily aims to document the interactions between contaminants and nutrients in preschool Inuit children from Nunavik. From 2006 to 2010, a total of 245 children were recruited and 110 of them were seen for a follow-up visit one year later. Heavy metals and persistent organic pollutants, dietary intakes, and nutritional status were measured at both visits. Children who consumed traditional food had significantly higher intakes of proteins, omega-3 fatty acids, and many vitamins and minerals than non-consumers. Thirteen percent of participants had values equal to, or exceeding the blood guidance value for methylmercury, or were above the Polychlorinated Biphenyl (PCB) level of concern. Moreover, 64.5% of children had a low vitamin D level and 50% of them suffered from iron deficiency. An inverse association was found between children’s iron status and blood lead levels. Tomato products and dietary calcium intake had a protective effect against mercury and lead exposure, respectively. In 2013-2014 the project team will complete the development of a communication plan with the Nunavik Nutrition and Health Committee (NNHC). Key findings will be delivered to target audiences including parents and frontline workers.


Synopsis (2011-2012):

Abstract
Children are particularly vulnerable to toxic exposures since their organs and nervous systems are still developing, and they may also have a poor nutritional status. Various nutrients and diet components may protect against the adverse effects of contaminants on health. This study was conducted as part of the Nutrition Program in Nunavik Childcare Centres. Blood contaminant levels, dietary intakes and nutritional status of participating children were measured at recruitment and twelve months later. Data collection is now complete (2006-2010) and statistical analysis is underway. A total of 245 children were recruited (mean age 25.1 ± 9.8 months) and 110 of them were seen at the follow-up visit. Mercury, lead, PCB-153, BDE-47, PFOS, and PFOA were detected in 97.5% to 100% of participating children. Exposure to mercury, p,p'-DDE and toxaphene Parlar 26 increased significantly between recruitment and the one-year follow-up visit, although these levels are still in agreement with the decreasing trends observed in other studies carried out in Nunavik residents of various age groups. On the contrary, exposure to BDE-47 decreased significantly over this period. Nevertheless, these levels are still higher than those reported in Nunavimmiut adults and of many children and adolescents worldwide. The present study on contaminant nutrient interactions will provide the scientific community, the public health authorities and Nunavimmiut essential information about dietary patterns and intakes, nutritional status and contaminant exposure of young Inuit children and the risks/benefits concerning the use of traditional foods during preschool age in the context of a healthy diet.

Key Messages

  • Between 2006 and 2010, 245 Nunavimmiut preschool children have been recruited across Nunavik, and 110 of them were seen for a follow-up visit one year after recruitment (representing 53% of children recruited from 2006 to 2009).
  • Blood levels of mercury, p,p'-DDE and toxaphene Parlar 26 increased significantly between recruitment and the one-year follow-up visit, although these levels are still consistent with the decreasing trends observed in the Nunavik population.
  • On the contrary, one "emerging contaminant", namely BDE-47, decreased significantly during the one-year period, despite the fact that it is still detected at higher levels in these preschoolers than in Nunavimmiut adults and in many children and adolescents worldwide.
  • Our previous results also suggested that, for the same level of consumption of traditional foods, the consumption of tomato products and an adequate calcium intake could reduce mercury and lead exposure respectively, thus providing essential information about the risks/benefits of traditional food consumption in the context of a healthy diet.
 

top of page

Monitoring of Environmental Pollutants in Maternal Blood in Nunavik : Time Trend Assessment and Evaluation of the Arctic Char Program

Project Leader: Eric Dewailly, Centre de Recherche du Centre Hospitalier Universitaire de Québec (CR-CHU); Département de médecine sociale et préventive de l’Université Laval.
E-mail: eric.dewailly@crchul.ulaval.ca

Project Team:

  • Serge Déry, Nunavik Regional Board of Health and Social Services;
  • Pierre Ayotte, CR-CHU and INSPQ;
  • Renée Dallaireand Gina Muckle, CR-CHU.

Northern Regions Included in the Study: Nunavik

Project Duration: 2011-2014

Project Summary (2013-2014)

Inuit are exposed to a wide range of environmental contaminants through their traditional diet, which includes significant amounts of fish and sea mammals. During the past twenty years, several studies have monitored the exposure of Nunavik Inuit to persistent organic pollutants (POPs) and heavy metals. A decreasing trend in human exposure has been observed for most POPs in Nunavik over the last two decades. Most of the biomonitoring data since 1997 originate from Hudson Bay and time-trend data are lacking for the Ungava Bay population. In addition, new emerging contaminants have now reached the Arctic food chain and very little is known about the body burden of these compounds. In contrast, mercury exposure appears more stable but remains a public health threat, as new data from Nunavik confirmed that mercury exposure during the prenatal period is detrimental for the unborn baby’s brain development. The Nunavik Regional Board of Health and Social Services (NRBHSS) have suggested new food advisories for women of child-bearing age recommending that they do not eat beluga meat. Moreover, in September 2011, in villages along Hudson Bay, the Inuulitsivik Health Centre, in collaboration with the NRBHSS, began a program that freely distributes Arctic char to pregnant women in order to reduce mercury exposure and to improve their nutritional status. The effectiveness of this program still needs to be assessed. This research project will continue the biomonitoring activities in Nunavik in order to 1) expand the biomonitoring of pregnant women to the Ungava Bay region for a limited list of POPs and metals as well as key nutrients; 2) assess exposure to new emerging environmental contaminants for which increasing concentrations in wildlife and human samples have been reported worldwide; 3) initiate the evaluation of the effectiveness of the Arctic Char program in reducing mercury exposure among pregnant women from the Hudson Bay area.

Synopsis (2012-2013):

Previous studies conducted in Nunavik in the early 90’s revealed that the Inuit population was exposed to a wide range of environmental contaminants through its traditional diet; this included several metals and persistent organic pollutants (POPs). Unfortunately, other studies revealed that prenatal exposure to mercury and some POPs was also associated with growth and effects on cognitive development in children. Hence, conducting monitoring activities seems essential 1) to ensure that exposure of Inuit mothers to these contaminants do not exceed the threshold limit values recommended by Health Canada, and 2) to facilitate the implementation of prevention programs related to this issue. Over the last 20 years, contaminant blood levels in pregnant Inuit women were measured during two health surveys conducted in 1992 and 2004. The current project aimed to extend the monitoring of temporal trends of environmental contaminants in maternal blood to cover a 20-year period (1992-2012). This year, we completed the recruitment of 95 pregnant women and started data analysis. Preliminary results suggest that levels of toxic metals and most POPs (including PCBs, chlorinated pesticides, perfluorooctane sulfonate and polybrominated diphenyl ethers) significantly decreased in maternal blood over the last two decades. Only PBDE153 seems to have significantly increased over the last 8 years.

Key Messages

  • Levels of lead, mercury and several legacy POPs seem to have significantly decreased over the last 20 years in pregnant Inuit women.
  • PBDE 153 exposure increased between 2004 and 2012.
  • Few Inuit mothers seem to have heard about the communication campaign of the Nunavik Child Cohort Study and related dietary recommendations for pregnant women.

Synopsis (2011-2012):

Inuit are exposed to a wide range of environmental contaminants through their traditional diet which includes significant amounts of fish and sea mammal. During the past twenty years several studies have monitored the exposure of Nunavik's Inuit to persistent organic pollutants and heavy metals. Since the late 90's increased emphasis was placed on health effects studies in relation to exposure to polychlorinated biphenyls chlorinated pesticides mercury and lead in Nunavik. This project proposes to restart the biomonitoring activities in Nunavik in order 1) to compare current exposure levels with those prevailing ten to twenty years ago based on our last surveys 2) to assess exposure to emerging environmental contaminants for which increasing concentrations in wildlife and human samples have been reported worldwide and 3) to monitor health effects in newborn related to contaminant exposure. Analyses were conducted on maternal blood, and the results provide an update of geographical patterns of exposure information about whether exposure levels to different classes of contaminants are increasing, decreasing, or remaining the same in northern populations, as well as information about the efficiency of intervention programs implemented following earlier surveys. During the year 2011-2012 this was conducted as a pilot project.

Key Messages

Although we present results of a small pilot study; measurements in the blood of Nunavik pregnant women in 2011 suggest that:

  • Organic contaminants concentrations have continue to drop or stabilize
  • Lead has also decreased
  • Trans fatty acids are very low
  • Omega-3 fatty acids have increased as well as selenium
  • Mercury exposure remains very high
 

top of page

Country Foods and Cardiovascular Health in Nunavik : Studying the Complex Balance Between Selenium and Environmental Contaminants

Project Leader: Pierre Ayotte, Department of Social and Preventive Medicine, Université Laval, Centre de recherche du CHU de Québec, and Institut national de santé publique du Québec (INSPQ).
E-mail: pierre.ayotte@inspq.qc.ca

Project Team:

  • Mélanie Lemire, Université Laval; Laurie Chan and Brian Laird, University of Ottawa, Department of Biology;
  • Éric Dewailly, Professor, Université Laval;
  • Pierre Dumas, INSPQ;
  • Michael Kwan, Nunavik Research Center (NRC)

Northern Regions Included in the Study: Nunavik

Project Duration: 2012-2014

Project Summary (2013-2014)

Selenium (Se) is an essential element found in significant levels in the traditional marine diet of Inuit, and their exposure to this element is among the highest in the world.In populations that eat fish and marine mammals, there is increasing evidence suggesting that high selenium intake may play a role in offsetting some of the negative effects of methylmercury (MeHg) exposure. However, in other populations, elevated selenium concentrations have been recently associated with diabetes and hypertension. In addition to selenium levels in blood, several other indicators have been identified and these may help to better characterise selenium status. The research team will investigate relations between these new indicators of selenium status and emerging health issues such as diabetes and cardiovascular diseases in Inuit adults, taking into account possible interactions with mercury and other environmental contaminants. The research team will also identify the forms of selenium and mercury present in various traditional foods. These much needed data will improve our capacity to assess the risks and benefits of selenium intake and the traditional marine diet in this population.

Synopsis (2012-2013):

Selenium (Se) is an essential element highly present in the traditional marine diet of Inuit and their exposure to this element is among the highest in the world. In fish and marine mammal eating populations, there is increasing evidence suggesting that high Se intake may play a role in offsetting some deleterious effects of methylmercury (MeHg) exposure. However, in other populations, elevated plasma Seconcentrations have been recently associated to type 2 diabetes, hypercholesterolemia and/ or hypertension. In addition to plasma Se levels, the most common biomarker of Se status, several other biomarkers (e.g. selenoproteins and small Se molecules such as selenoneine) have been identified and these may help to better characterise Se status. We will investigate relations between these new biomarkers of Se status and emerging health issues such as diabetes and cardiovascular diseases in Inuit adults, taking into account possible interactions with mercury and other environmental contaminants. We will also identify the forms of selenium and mercury present in various traditional foods and their bioaccessibility. These much needed data will improve our capacity to assess the risks and benefits of Se intake and the traditional marine diet in this population.

Key Messages

  • Beluga meat, seal liver and lake trout contain very high total Hg concentrations;
  • Seal liver, beluga mattaaq and sculpin eggs are exceptionally high in Se;
  • Hg bioaccessibility varies greatly among country foods;
  • Selenium and mercury speciation in plasma samples of Inuit adults and country food samples are on-going.
 

top of page

Quantifying the Effect of Transient and Permanent Dietary Transitions in the North on Human Exposure to Persistent Organic Pollutants and Mercury

Project Leaders:

Frank Wania, Department of Physical and Environmental Sciences, University of Toronto Scarborough, Toronto
Tel: (416) 287-7225; E-mail: frank.wania@utoronto.ca

Meredith Curren, Health Canada, Environmental Health Science and Research Bureau, Chemicals Surveillance Division, Ottawa
Tel: +1-613-941-3570, E-mail: Meredith.Curren@hc-sc.gc.ca

Project Team :

Mélanie Lemire, CHU de Quebec Research Centre, Quebec; James Armitage, University of Toronto Scarborough, Toronto; Laurie Chan, University of Ottawa, Ottawa

Duration: 2012- present

Northern Regions: Nunavut, Northwest Territories

Project Summary (2016-2017)

The overall objective of this research project is to quantify the effect of dietary changes on the exposure of humans to persistent organic pollutants (POPs) and mercury. A key component of the project is the application of computer-based simulation models to estimate uptake and accumulation of contaminants in humans. Experiences to-date have highlighted that a main uncertainty in exposure modeling of POPs is the reliability of estimated food intake rates, particularly for traditional food items. However, since the elimination kinetics of methylmercury (MeHg) in humans is relatively rapid and well understood, a MeHg bioaccumulation model could be applied to available biomonitoring data in humans and dietary items in order to assess the potential discrepancies (e.g. ‘recall’ or ‘recency’ bias) in estimated food intake rates. This will be a collaborative and iterative process involving territorial health authorities, Indigenous organizations, and individuals from Northern communities. The first task will be the development and application of accessible, ‘user-friendly’ mercury exposure assessment tools, followed by wider dissemination and use by the public. In addition to informing exposure assessments for MeHg and other contaminants (e.g. POPs), it is hoped that these tools will facilitate a greater understanding of contaminant exposure issues at the community level.

Synopsis (2015-2016)

Abstract

Human exposure to persistent organic pollutants (POPs) in both industrialized and remote regions is strongly influenced by diet. What we eat and where these food items originate are key determinants of body burden and risks associated with chronic exposure to such compounds. It is well known that all foods are not equal with respect to contamination by POPs.A result of these differing contaminant levels is that contaminant exposure can be affected by changes in diet. Therefore we have investigated the impact of dietary transitions on human POP exposure, with examples of transient adjustment, e.g. if a woman who is pregnant temporarily avoids food items known to be more contaminated, and more gradual and permanent changes, e.g. if communities gradually shift from a traditional diet of locally hunted animals to a diet that includes more imported food (IF). We have developed a series of computer simulation-based food chain bioaccumulation models that quantify how much such dietary changes can affect exposure to contaminants. Applications range from exploring general population-wide transitions away from Northern traditional food (TF) to investigating individuals temporarily adjusting their diet during child-bearing age. Our main findings from this past year are that (1) the quality of the data on dietary compositional trends currently challenges the ability to determine the impact of long-term dietary transitions on human POP exposure in Canada’s North (2) short-term dietary transitions may considerably affect intakes of POPs and essential nutrients in sensitive Arctic populations, and (3) traditional food preparation methods can significantly alter POP levels in these unique food items.

Key Messages

  • Arctic dietary dilemma derives from balancing nutritional benefits of, and contaminant intakes from, traditional food derived from marine mammals (MMs)
  • Temporarily reducing MM consumption is ineffective in lowering PCB exposure, and reduces intakes of selenium and other nutrients
  • Whether it’s advisable to increase MM consumption during childbearing age for nutritional enhancement depends on baseline consumption
  • Certain beluga blubber TF preparation processes (ageing, roasting) consistently and significantly altered levels of particular nutrients and contaminants: polyunsaturated fatty acids (PUFAs), selenium (Se), mercury (Hg), and ionogenic POPs
  • Preparation processes may also introduce environmental contaminants to beluga blubber TFs not present in raw tissues [polycyclic aromatic hydrocarbons (PAHs)]
  • Based on contaminant and nutrient changes due to preparation, aged inner blubber (uqsuq) represents the beluga blubber TF for which PUFA consumption can be maximized, while environmental contaminant intake is minimized (Hg, ionogenic POPs). However, ageing uqsuq also noticeably depleted Se

Synopsis (2014-15)

Abstract

Human exposure to persistent organic pollutants (POPs) in both industrialized and remote regions is strongly influenced by diet. What we eat and where these food items originate are key determinants of body burden and risks associated with chronic exposure to such compounds. It is well known that all foods are not equal with respect to contamination by POPs. This implies that contaminant exposure can be affected by changes in diet. Therefore we have investigated the impact of dietary transitions on human POP exposure, with examples of transient adjustment (e.g.if a woman who is pregnant temporarily avoids food items known to be more contaminated), and more gradual and permanent changes (e.g.if communities gradually shift from a traditional diet of locally hunted animals to a diet that includes more imported food [IF]). We have developed a series of computer simulation-based food chain bioaccumulation models that quantify how much such dietary changes can affect exposure to contaminants. Applications range from exploring general population-wide transitions away from Northern traditional food (TF) to investigating individuals temporarily adjusting their diet during child-bearing age. Our main findings from this past year are that (1) discerning the impact of long-term dietary transitions in Canada’s North on observed human POP exposure trends greatly relies on, and is currently challenged by, the quality of the data on dietary compositional trends, (2) short-term dietary transitions may appreciably affect intakes of POPs and essential nutrients in sensitive Arctic populations, and (3) traditional food preparation methods can significantly alter POP levels in these unique food items.

Key Messages

  • Large-scale generational dietary transitions among Aboriginal Northern communities are an important factor underlying observed POP body burden temporal declines, as well as contributing to the variability within and between subpopulations.
  • Associations between POP concentrations and demographic variables such as sex and age in traditional food species can help inform Northern dietary choices; for example, suggesting individuals susceptible to POP toxicity limit their consumption of older male animals, as they routinely possess the greatest POP levels within wildlife populations.
  • The incorporation of several new TF species models (e.g., beluga whale, narwhal, caribou, Canada goose) into our food chain bioaccumulation framework has allowed us to estimate POP exposures for women who participated in maternal biomonitoring studies in two Northern communities (Baffin Island and Inuvik). The accuracy of our predictions was highly variable between studies, and indicated that model effectiveness was directly tied to the quality of biomonitoring data and dietary survey inputs, particularly recall estimates of TF intake rates.
  • Our updated model is now also capable of calculating daily intake rates of several essential nutrient groups (minerals, vitamins, and poly-unsaturated fatty acids) from TF consumption, and we have made initial calculations estimating the impact of short-term dietary transitions (i.e. during pregnancy and nursing) on POP and nutrient intakes for hypothetical Canadian Aboriginal Arctic TF replacement scenarios.
  • Initial results from our field/laboratory study on the influence of food preparation on beluga blubber TF contaminant and nutrient yields suggest that different processes can substantially affect POP levels in consumed food items.

Synopsis (2013-2014)

Abstract

Human exposure to persistent organic pollutants (POPs) in both industrialized and remote regions is strongly influenced by diet. What we eat and where these food items originate are key determinants of body burden and risks associated with chronic exposure to such compounds. It is well known that all foods are not equal with respect to contamination by POPs. This implies that contaminant exposure can be affected by changes in diet. Therefore we have investigated the impact of dietary transitions on human POP exposure, with examples of transient adjustment, e.g. if a woman who is pregnant temporarily avoids food items known to be more contaminated, and more gradual and permanent changes, e.g. if communities gradually shift from a traditional diet of locally hunted animals to a diet that includes more imported food. We have developed a series of computer simulation-based food chain bioaccumulation models that quantify how much such dietary changes can affect exposure to contaminants. They have been applied to general population-wide transitions away from Northern traditional food, as well as to specific aboriginal Arctic communities, also to investigation of the impacts of various wildlife demographic variables (ex. age, sex, lifespan) on expected human exposure from traditional food consumption, and to temperate human populations complying with POP food consumption advisories. Our main findings are that (1) the long-term generational movement away from traditional food intake in Canada’s North greatly affected observed human POP exposure trends, and (2) traditional food consumers susceptible to POP exposure toxicity (i.e. pregnant or nursing mothers) may want to preferably consume younger, reproductively active female animals, as these individuals typically possess lower contaminant levels. Additionally, our initial investigation of short-term dietary transition impacts among temperate populations suggests that these may have a negligible effect on POP levels, especially for compounds exhibiting long human elimination half-lives.

Key messages

  • Large-scale generational dietary transitions among Aboriginal Northern communities are an important factor underlying observed POP body burden temporal declines, as well as contributing to the variability within and between subpopulations.
  • The incorporation of several new models for additional traditional food species (ex. bowhead whale, beluga whale, narwhal, caribou) into our greater food chain bioaccumulation framework has provided a more holistic representation of common traditional Aboriginal diets, and initial evaluations of expanded model performance using Aboriginal (mainly Inuit and Dene/Metis) biomonitoring data from two Northern communities (Baffin Island and Inuvik) have produced promising results.
  • Associations between POP concentrations and demographic variables such as sex and age in traditional food species can help inform Northern dietary choices; for example, suggesting individuals susceptible to POP toxicity limit their consumption of older male animals, as they routinely possess the greatest POP levels within wildlife populations.
  • When assuming realistic periods of compliance (i.e. only during a nominal 1.5 year period of pregnancy and breastfeeding), maternal food advisories are largely ineffective in reducing pre- and postnatal exposure to POPs with exceptionally long human elimination half-lives.

Synopsis (2012-2013):

Abstract

Human exposure to persistent organic pollutants (POPs) in both industrialized and remote regions is strongly influenced by diet. What we eat and where these food items originate are key determinants of body burden and risks associated with chronic exposure to such compounds. It is well known that all foods are not equal with respect to contamination by POPs. This implies that contaminant exposure can be affected by changes in diet. Therefore we have investigated the impact of dietary transitions on human POP exposure, with examples of transient adjustment, e.g. if a woman who is pregnant temporarily avoids food items known to be more contaminated, and more gradual and permanent changes, e.g. if communities gradually shift from a traditional diet of locally hunted animals to a diet that includes more imported food. We have developed a series of computer-based simulation models that quantify how much such dietary changes can affect exposure to contaminants. They have been applied in the context of population-wide transitions away from traditional food among aboriginal Arctic groups, as well as for temperate populations temporarily complying with POP food consumption advisories. Our main findings are that the movement away from traditional food intake in Canada’s North greatly affected observed human POP exposure trends. However, initial investigations for a Southern population suggest that short-term dietary transitions may be having a negligible effect on POP levels, especially for compounds exhibiting long human elimination half-lives.


Key Messages

  • Large-scale dietary transitions among aboriginal Northern communities are important factors underlying observed POP body burden temporal declines, as well as contributing to the variability within and between subpopulations.
  • When assuming realistic periods of compliance (i.e. only during the 1.5 year period of pregnancy and breastfeeding), maternal food advisories are largely ineffective in reducing pre- and postnatal exposure to POPs with exceptionally long human elimination half-lives.
  • Biomonitoring sampling year relative to year of peak Arctic environmental POP concentrations is a critical parameter in determining age-body burden trends of Northern human and wildlife populations; gender effects further contribute to variability in these relationships, while lifespan differences play a more limited role in determining age-body burden trends.
  • Several new POP food chain bioaccumulation models (ex. bowhead whale, beluga whale, caribou) are being incorporated into our current Northern human exposure-modeling framework, to more holistically represent common traditional aboriginal diets.
 

top of page

Development of Blood Guidance Values for Persistent Organic Pollutants for the Canadian Arctic

Project Leader(s):

Dr. Laurie H.M. Chan, Professor and Canada Research Chair in Toxicology and Environmental Health, Center for Advanced Research in Environmental Genomics, University of Ottawa, Tel: (613) 562-5800 ext 6349, Fax: (613) 562-5385

Email: laurie.chan@uottawa.ca

Project Team:

Andy Nong, Environmental Health Science and Research Bureau, Health Canada; Mark Feeley, Bureau of Chemical Safety, Health Canada; Annie St-Amand, National Biomonitoring Section, Health Canada; Kavita Singh, PhD Student, University of Ottawa

Abstract:

The Adult Inuit Health Survey (2007-2008) collected data on blood levels of heavy metals and persistent organic pollutants in participants from the Canadian North. The population-level risks of contaminant exposures can be assessed using biomonitoring equivalents, which are the corresponding internal doses of maximum recommended intake reference standards. The purpose of this project is to develop new biomonitoring equivalents for chlordane, toxaphene, and polychlorinated biphenyls and explore the use these biomonitoring equivalents to assess of the biomonitoring data collected in the Canadian North. During the 2014-2015 fiscal year, information needed to derive biomonitoring equivalents, was collected from the literature. Several reference standards are available from organizations such as Health Canada, the Environmental Protection Agency, and European authorities. Also developed was a pharmacokinetic modeling strategy and identification of pharmacokinetic parameters needed to model internal contaminant behaviour based on absorption, distribution, metabolism, and excretion. The work completed in the first year of the project will be used for carrying out one-compartment pharmacokinetic modeling during the second year of the project.

Key messages:

· Biomonitoring equivalents are the corresponding internal doses of intake reference standards and can be used to assess population-level risks of contaminant exposures.

· Currently there are no biomonitoring equivalents for chlordane, toxaphene, and polychlorinated biohenyls and, therefore, the purpose of this project is to develop biomonitoring equivalents for these contaminants and use them to interpret biomonitoring data of the Inuit Health Survey and the Canadian Health Measures Survey.

· Oral intake reference standards are available for technical chlordane, technical and weathered toxaphene, and polychlorinated biphenyls (dioxin-like, non-dioxin like, commercial mixtures, total) from various organizations. These values or the no-observed adverse effect level/lowest-observed adverse effect level will be used as the point of departures for deriving the biomonitoring equivalents.

· A hierarchical pharmacokinetic modelling strategy will be employed to model contaminant behaviour in the body, using a simple one-compartment model as the starting point.

· The biomonitoring equivalents will be used to determine the percentage of the sample population that exceeds recommended guidance values.

 

top of page

Do Country Food Nutrients Protect Against Mercury Toxicity and Cardiometabolic Diseases? Integrating Data from Cutting-Edge Science and Mobilizing Knowledge Towards Nunavimmiut Health

Project Leader:

Pierre Ayotte, Ph.D., Toxicologist, Professor, Dept. of social and preventive medicine, Université Laval; Research Scientist, Axe en santé publique et pratiques optimales en santé, Centre de recherche du-CHU de Québec; Head, Biomarker laboratory, Institut national de santé publique du Québec (INSPQ).

Tel: (418) 650-5115 ext. 4654, Fax: (418) 654-2148, Email: pierre.ayotte@inspq.qc.ca

Project Team:

Mélanie Lemire, Ph.D., Assistant Professor and Nasivvik Chair, Université Laval, Quebec; Pierre Dumas, B.Sc., Chemist, INSPQ, Québec; Michel Lucas, Ph.D., Assistant Professor, Université Laval, Quebec; Ellen Avard, Ph.D and Michael Kwan, Ph.D., Nunavik Research Centre, Kuujjuaq; Guillaume Massé, Ph.D, Associate Professor, Université Laval, Takuvik; Abdullah Al Maruf, Ph.D., Post-doctoral fellow, and Adel Achouba, M.Sc., Nathalie Ouellet, M.Sc., Cynthia Roy, B.Sc., Pierre-Yves Tremblay, M.Sc, Axe en santé des populations et pratiques optimales en santé, Centre de recherche du CHU de Québec, Quebec

Duration: 2014- present

Project Summary (2016-2017)

Despite a decreasing trend over the last decades, methylmercury (MeHg) exposure in the Inuit population of Nunavik is still among the highest in the world. Traditional marine foods are the major source of this exposure, but are also exceptionally rich in nutrients such as selenium (Se) and omega-3 polyunsaturated fatty acids (n-3 PUFA). Through an interdisciplinary program incorporating nutrition, epidemiology, toxicology, oceanography, and implementation research, this project addresses the complex issue of risks and benefits of country foods in the Inuit population of Nunavik, especially with regard to cardiometabolic diseases, Se-Hg interactions, and respective toxicity. In addition to continuing the integration of data obtained during the 2012-2015 program, this coming year will focus on better defining the origin in the Arctic marine food chain of selenoneine, a new selenocompound recently identified in Inuit blood and beluga mattaaq, and the interaction between this compound and MeHg in red blood cells. Furthermore, Type 2 diabetes mellitus (T2D) prevalence among Inuit in Nunavik has been low compared to that of general populations, and much lower than in most Aboriginal populations. However the dietary and lifestyle transition occurring in the Inuit population of Nunavik may change the situation in the near future. An emerging risk factor is MeHg exposure. Therefore, there is an urgent need to determine if validated predictive biomarkers of T2D are reduced by MeHg exposure and by recognized protective factors in the traditional diet, such as Se, Se-compounds, and n-3 PUFA. The integration of these much-needed data will increase our understanding of the determinants of T2D and cardiovascular diseases risk in this population. In addition, it will improve our capacity to develop and implement interventions that aim to promote the benefits of country food diet of marine origin, while minimizing MeHg exposure in this population.

Synopsis (2015-2016)

Abstract

Methylmercury (MeHg) exposure in the Inuit population of Nunavik remains one of the highest in the world. Traditional marine foods are the major source of this exposure, in addition to being rich in nutrients such as selenium (Se) and omega-3 polyunsaturated fatty acids (n-3 PUFA). Through an interdisciplinary program incorporating nutrition, epidemiology, toxicology and implementation research, we are addressing the complex issue of benefits and risks of country foods in the Inuit population of Nunavik, with a particular focus on cardiovascular diseases and type 2 diabetes (T2D). This year, we have started exploring associations between biomarkers of MeHg exposure, Se status and n-3 PUFA status, and biomarkers of T2D-related effects (plasma levels of adiponectine, branched-chain amino acids and acylcarnitines). Following up on the identification of selenoneine as the major selenium compound present in Inuit red blood cells (RBCs) and in beluga mattaaq, we completed the determination of selenoneine in RBCs of all 2004 Nunavik Health Survey participants. Results indicate that selenoneine is a major Se species in Nunavimmiut RBCs. We also measured selenoneine in beluga mattaaq samples from Nunavik and Arviat (Nunavut) and found that selenoneine represents more than 50% of the total selenium concentration in this marine food. Selenoneine and MeHg both accumulate in RBCs, where selenoneine may enhance MeHg demethylation and therefore decrease MeHg distribution to target organs. These results will improve our capacity to develop and implement interventions that aim to promote the benefits of the traditional marine diet, while minimizing MeHg toxicity in this population.

Key messages

  • Selenoneine, an organic form of selenium, represents more than 50% of selenium in beluga mattaaq samples from Nunavik and Nunavut
  • Selenoneine was identified as a major Se compound in red blood cells of Nunavimmiut
  • Selenoneine may enhance methylmercury demethylation and decrease its distribution to target organs
  • Whether or not selenoneine protects against methylmercury toxicity is currently being examined

Synopsis (2014-2015)

Abstract:

Despite a decreasing temporal trend over the last decades, methylmercury (MeHg) exposure in the Inuit population of Nunavik is still high. Traditional marine foods are the major source of this exposure, but are also rich in nutrients such as selenium (Se) and omega-3 polyunsaturated fatty acids (n-3 PUFA). Through an interdisciplinary program incorporating nutrition, epidemiology, toxicology and implementation research, we are addressing the complex issue of benefits and risks of country foods in the Inuit population of Nunavik, in particular with regard to cardiovascular diseases and type 2 diabetes (T2D). Early biomarkers of such diseases, i.e. branched chain amino acids and acylcarnitines, were measured in plasma obtained from participants to the 2004 Nunavik Health Survey (NHS) and their associations with biomarkers of MeHg exposure, Se status (plasma levels of Se-containing proteins determined in last year’s project) and n-3 PUFA status are being examined. In addition, in view of last year’s results indicating that Se accumulates disproportionally in blood cells compared to plasma of Inuit, we performed additional experiments to identify selenocompounds present in red blood cells of NHS participants and Se-rich country foods. Genetically-modified yeast was used to synthesize selenoneine, an organic form known to be present in marine foods. Using this standard, we confirmed that selenoneine is the major selenium compound present in Inuit red blood cells and in beluga muktuk. An analytical method was developed and is currently used to measure selenoneine in red blood cells of all 2004 NHS participants and Se-rich marine foods. Finally, in vitro experiments were conducted to further investigate the bioavailability and speciation of Hg and Se in country foods as well as examine the protective role played by selenomethionine on the bioavailability of Hg from marine foods. The integration of these much needed data will increase our understanding of the determinants of T2D and cardiovascular diseases (CVD) risk in this population. In addition, it will improve our capacity to develop and implement interventions that aim to promote the benefits of traditional marine diet, while minimizing MeHg exposure in this population.

Key messages:

  • Exceptionally high blood Se levels are observed in this population, while plasma levels are similar to those of the general Canadian population
  • Selenoneine, an organic form of selenium, was identified as the major Se compound in red blood cells of Inuit
  • This selenocompound was also found in high concentration in beluga muktuk extracts
  • Se was positively correlated with the Hg levels in whitefish, eider duck eggs, beluga nikku , and ringed seal liver
  • Selenomethionine was the major selenocompound within most enzyme-digested country foods
  • Selenomethionine occasionally decreases the bioavailability of Hg in vitro
 

top of page

Lake Melville and Labrador Inuit: Understanding and Projecting Human Health Implications of Exposure to Local and Long-Range Mercury Sources

Project Leader(s):

Tom Sheldon, Director of Environment, Nunatsiavut Government, Tel: (709) 922-2588, Fax: (709) 922-1040

Email: tom_sheldon@nunatsiavut.com

Project Team:

Elsie Sunderland, Harvard University, Cambridge MA; Ryan Calder, Harvard University, Boston MA; Rodd Laing, Michele Wood, and Marina Biasutti-Brown, Nunatsiavut Government; Community Research Advisory Committees for Rigolet, North West River, and Happy Valley-Goose Bay/Mud Lake, Nunatsiavut

Abstract:

The goal of this Human Health project is to better understand how Inuit living on Lake Melville might potentially be exposed to methylmercury (MeHg) through the consumption of country foods.  The study consisted of two parts: 1) a food frequency survey to find out how much fish, seal and other country foods are being consumed from the Lake Melville environment over three different seasons (Winter, Spring hunt and Fall freeze-up), and 2) collecting hair samples to measure mercury exposure.  A total of 1566 surveys were conducted and 658 hair samples provided by Inuit participants in the communities surrounding Lake Melville: Rigolet, North West River, Happy Valley-Goose Bay and Mud Lake.  Survey and hair sampling work was carried out by 28 local Inuit Research Assistants.  Sample sizes obtained are high, with dietary survey data representing 46% of the Lake Melville Inuit population, and hair sample analysis representing 20% of the Lake Melville Inuit population.

Survey data is currently being analyzed to identify magnitudes and frequencies of country food consumed from Lake Melville by Inuit.  Hair samples have been analyzed for Hg concentration, and individual results are being mailed directly to participants in May 2015.  Dietary survey results are being corroborated using hair Hg biomarkers, and our research team is developing a probabilistic human exposure model based on dietary survey data and anticipated changes in MeHg levels of country foods to estimate future changes in MeHg exposures and health risks of Inuit corresponding to climate variability and flooding of the Lower Churchill River.  Publication of study results will begin once individual Hg analysis has been appropriately communicated to participants, with ample time for follow-up and consultation.

Key messages:

·  Inuit are concerned about the possibility of increased methylmercury (MeHg) in the foods that they harvest from Lake Melville as a result of past and future hydro development on the Churchill River as well as climate change. 

· Local Inuit led the collection of dietary information over three seasons, surveying Inuit living in the Lake Melville communities of Rigolet, North West River, Happy Valley-Goose Bay and Mud Lake about the types of country food consumed, quantity, frequency and preparation.  Inuit researchers also collected hair samples for analysis of mercury (Hg) exposure.

· Data gathered from the dietary surveys has provided insight into which country foods should be given the highest priority for monitoring of contaminants.  Hair samples have been analyzed for Hg, and are being cross-validated with results of the dietary survey.  Baseline levels of Hg exposure in the Inuit community have been established.

· This research complements environmental work already completed, and feeds into a human health exposure model to estimate future changes in MeHg exposures and health risks of the Inuit related to climate variability and flooding of the Lower Churchill River.

 

top of page

Exposure to food chain contaminants in Nunavik: evaluating spatial and time trends among pregnant women & implementing effective health communication for healthy pregnancies and children

Project Leaders

Mélanie Lemire, PhD, Assistant Professor and Nasivvik Chair, Dept. of social and preventive medicine, Université Laval; Axe santé publique et pratiques optimales en santé, Centre de recherche du CHU de Québec, Québec
Tel : (418) 525-4444, ext.46535; Email : melanie.lemire@crchuq.ulaval.ca

Pierre Ayotte, PhD, Professor, Dept. of social and preventive medicine, Université Laval; Axe santé publique et pratiques optimales en santé, Centre de recherche du CHU de Québec;
Head, Biomarker laboratory, Institut national de santé publique du Québec (INSPQ)
Tel: (418) 650-5115 ext.4654; Fax: (418) 654-2148; E-mail: pierre.ayotte@inspq.qc.ca

Chris Furgal, PhD (co-PI), Associate Professor, Indigenous Environmental Studies Program
Nasivvik Centre for Inuit Health and Changing Environments, Trent University
Tel: (705) 748-1011 ext.7953; Fax: (705) 748-1416; E-mail: ChrisFurgal@trentu.ca

Catherine Pirkle, PhD, Assistant Professor, Health Policy and Management, Office of Public Health Studies, University of Hawai’i at Manoa
Tel: (808) 956-8748; E-mail: cmpirkle@hawaii.edu

Project team

Amanda D. Boyd, PhD, Assistant Professor, Washington State University; Gina Muckle, PhD, École de psychologie, Université Laval; Sylvie Ricard, Nunavik Regional Board of Health and SocialServices, Quebec; Marie-Josée Gauthier, R.N. and Caroline d’Astous,Nunavik Regional Board of Health and Social Services, Kuujjuaq; Carole Beaulne, Ilagitsuta Family House, Inuulitsivik Health Center,Puvirnituq; Ellen Avard, PhD and Michael Kwan, PhD, Nunavik Research Centre, Kuujjuaq; Suzanne Côté, MSc and Thérèse Adamou, MSc, Centre de recherche du CHU de Québec, Québec.

Duration: 2016- present

Northern Regions: Nunavik

Project Summary (2016-2017)

Inuit are exposed to a wide range of environmental contaminants through their traditional diet, which includes significant amounts of fish and sea mammals. Despite a decreasing trend mostly due to reduced country food consumption, mercury (Hg) exposure remains a topical issue, particularly among pregnant women in Nunavik. Building on research since 2011, this three-year project aims at contributing to on-going international biomonitoring efforts on long-range environmental contaminants exposure among pregnant women in Nunavik. The project also aims at evaluating the comprehension and effectiveness of health and dietary recommendations among pregnant women, caregivers, and the general population. In Year 2, the goal is to develop and pilot new communication tools, while in Year 3 the effectiveness of these tools will be evaluated. Using this interdisciplinary and intersectoral approach, this project will set the groundwork to promote healthy pregnancies and children at community, regional (i.e. Nunavik), and international scales.

 

top of page

Tukisinirlungniq: Understandings of the Risks and Benefits of Consuming Beluga in Arviat, NU

Project Leaders:

Shirley Tagalik, M.Ed. (Community lead), Arviat Wellness Center, Tel: (867) 857-2159

Email: tagaliktwo@hotmail.com

Chris Furgal, PhD (Academic co-lead), Indigenous Environmental Studies Program

Nasivvik Centre for Inuit Health and Changing Environments, Trent University, Tel: (705) 748-1011 ext. 7953, Fax: (705) 748-1416

E-mail: ChrisFurgal@trentu.ca

Amanda Boyd, PhD (Academic co-lead), The Edward R. Murrow College of Communication

Washington State University, Tel: (509) 335-7252, Fax: (509) 335-3772

E-mail: Amanda.Boyd@wsu.edu

Project Team (in alphabetical order):

Sarah Arnold, Nunavut Parks and Fisheries, Rankin Inlet; Laurie Chan, PhD, Center for Advanced Research in Environmental Genomics, University of Ottawa; Sarah Curley,

Arviat Wellness Center; Mélanie Lémire, PhD, Centre de Recherche CHUQ, Université Laval; Gary Stern, PhD, University of Manitoba

Abstract:

This goal of this project is to enhance our understanding of the factors influencing food choices in Inuit communities and the potential role that concern over contaminants, and the legacy of past health advice or advisories may play in the consumption of country food items. It is an action-oriented project co-led by the Community of Arviat, NU Wellness Centre and Trent and Washington State Universities. Since the early 1970s, residents of Arviat have been hunting beluga whales and consuming only the maaqtaq. Meat, which used to be consumed dry and fresh is now routinely given to the dogs or discarded. Arviat, like other Inuit communities, faces various food security challenges and needs current information relating to the viability and feasibility of different culturally acceptable food options for its’ population. This project proposes to use a mental models approach to explore the current perceptions and misperceptions regarding the safety of beluga whales as a country food item in this community. In conjunction with the generation of up to date beluga contaminants (mercury-Hg) and nutrients (selenium-Se) data from the area, this project proposes to generate updated health messages on the consumption of beluga for this population. This messaging will be developed in consideration of current perceptions and misperceptions of the safety (health benefits and risks) of consuming beluga as a country food item, current levels of Hg and Se in these food items and current diet behavior and levels of exposure to contaminants in the region. This project has value to other similar cases across the North where the legacy of past contaminant advisories is currently unknown or where uncertainty exists regarding the impacts of contaminant perception on current diet behaviour.

Key messages:

· The goal of this research is to assess factors influencing local decisions regarding the consumption of beluga in Arviat.

· Surveys and mental model interviews have been completed in Arviat to better understand perceptions of contaminants as well as the risks and benefits of consuming beluga.

· MeHg, THg and Se were measured from locally sampled belugas (including maaqtaq, muscle, liver and dried nikku).

· Communication messages will be developed and delivered based on Arviat residents’ perceptions of beluga consumption and the analysis of nutrients and contaminants in beluga samples.

 

top of page

Genetic Polymorphisms to Improve Interpretation of Contaminant Exposure and Risk in Inuit

Project Leaders:

Niladri (Nil) Basu, Associate Professor, Canada Research Chair (CRC) in Environmental Health Sciences, Center for Indigenous Peoples’ Nutrition and Environment (CINE), McGill University, St. Anne de Bellevue
Tel: 514-398-8642; Email: niladri.basu@mcgill.ca

Laurie Chan, PhD, Professor, Director of CAREG, Canada Research Chair (CRC) in Environmental Health and Toxicology, University of Ottawa, Ottawa
Tel: (613) 562-5800 ext 6349; Email: laurie.chan@uottawa.ca

Pierre Ayotte PhD, Public Health Research Unit, Centre Hospitalier Universitaire de Québec (CHUQ), Québec
Tel : (418) 650-5115 Ext. #4654; Fax (418) 654-2148; Email : pierre.ayotte@crchul.ulaval.ca

Project Team Members:

Dr. Kami Kandola, Deputy Chief Medical Health Officer, Inuvialuit Settlement Region; Dr. Robert Hegele, The Blackburn Cardiovascular Genetics Laboratory, Robart Research Institute, London; Melanie Lemire PhD, Assistant Professor, Université Laval.

Duration: 2014- present

Project Summary (2016-2017)

The goal of this gene-environment research project is to better understand how Inuit process contaminants so that dietary exposure assessments, biomarkers (e.g. blood persistent organic pollutants), and linkages to health outcomes can be improved. The central hypothesis is that genetic polymorphisms will improve our understanding of the relationship between dietary exposure and blood concentrations of mercury, selenium, polychlorinated biphenyls (PCBs), and other persistent organic pollutants among Inuit. The overall project focuses on two geographically separated communities in Inuvialuit and Nunavik for which there is detailed epidemiological data and consent for genetics research. To our knowledge, this will be among the first studies to explore gene-contaminant interactions among Inuit and address a critical knowledge gap in the field. The findings will be shared with community leaders, the Northern Contaminants Program, and the Inuit Health Survey national steering committee.  Results will provide useful information to assist health professionals and policy makers at regional, provincial, territorial, national, and international levels in developing environmental health policies and aid Inuit in making informed dietary choices.

Synopsis (2015-2016)

Abstract:

The project’s goal is to better understand how Inuit ‘process’ contaminants. The ultimate goal is to arm public health decision makers with knowledge to help identify the most susceptible subpopulations and make informed and objective risk assessments. The central hypothesis was that analysis of polymorphisms in environmentally-responsive genes that help the body ‘process’ toxicants will increase understanding and utility of exposure biomarkers of mercury, PCBs, and other persistent organic pollutants. Over the past two funding years, previously collected samples were studied from some members of the Inuvialuit community (N=288 participants) who participated in the 2007-2008 International Polar Year Inuit Health Survey. Blood contaminants (Hg, Cd, Pb, Se, DDE, PCB-153) and fatty acids (DHA, EPA) levels were related to genetic polymorphisms, while considering pertinent covariates. Several polymorphisms emerged to be influential, indicating that environmentally-responsive genes can influence contaminant and nutrient biomarker levels. A similar gene-environment study is now being carried out with participants from Nunavik (N=669 participants) as part of the 2004 Qanuippitaa Survey.

Key messages:

  • 146 genetic polymorphisms were characterized from some members of the Inuvialuit community
  • These polymorphisms hail from biological pathways associated with the transport and metabolism of contaminants and cardiovascular health
  • Composition of many of the genetic polymorphisms were different when compared against other populations (such as Caucasians and Asians)
  • Some genes are associated with changes in blood levels of mercury, cadmium, lead, and other contaminants
  • Next steps include repeating the gene-environment study with previously collected samples and information from the 2004 Qanuippitaa Survey in Nunavik

Synopsis (2014-2015)

Abstract:

The project’s goal is to better understand how Inuit ‘process’ contaminants.  The ultimate goal is to arm public health decision makers with knowledge to help identify the most susceptible subpopulations and make informed and objective risk assessments.  Here, the central hypothesis was that analysis of polymorphisms in environmentally-responsive genes that help the body ‘process’ toxicants will increase understanding and utility of exposure biomarkers of mercury, PCBs, and other persistent organic pollutants. During the past year we studied already collected samples from some members of the Inuvialuit community (N=288 participants) who participated in the 2007-2008 International Polar Year Inuit Health Survey. Of the 360 genetic polymorphisms selected for study, 146 yielded statistically useful data and they hail from biological pathways associated with, for example, the transport and metabolism of contaminants and cardiovascular health.  The composition of many of the genetic polymorphisms studied were different when compared against other populations such as Caucasians and Asians.  Several of the genes were associated with significant changes in blood mercury levels. Next steps will be to further integrate the genetic data with the already-collected information on other contaminants, life-style and diet.

Key messages:

  • 146 genetic polymorphisms were characterized from some members of the Inuvialuit community who participated in the 2007-2008 International Polar Year Inuit Health Survey
  • Composition of many of the genetic polymorphisms were different when compared against other populations such as Caucasians and Asians
  • Some genes are associated with changes in blood mercury levels
  • Next steps will be to further analyze the genetic data with existing information on other contaminants and health measures
 

top of page

Contaminant Biomonitoring in the Northwest Territories Mackenzie Valley: Investigating the Links Between Contaminant Exposure, Nutritional Status, and Country Food Use (Year 2)

Project leader:

Brian Laird, Assistant Professor, School of Public Health and Health Systems, University of Waterloo
Tel: (519)-888-4567 x 32720; Fax: (519) 746-6776; Email: brian.laird@uwaterloo.ca

Project team members:

Mylène Ratelle, Rhona Hanning, and Shannon Majowicz, School of Public Health Systems, University of Waterloo; Ken Stark, and Ellen Reyes, Department of Kinesiology, University of Waterloo; Michael Power, and Heidi Swanson, Department of Biology, University of Waterloo; Chris Furgal, Indigenous Environmental Studies Program, Trent University; Michèle Bouchard, University of Montreal; Amanda Boyd, The Edward R. Murrow College of Communication, Washington State University; George Low, Dehcho First Nations; Deborah Simmons, Sahtú Renewable Resources Board.

Duration: 2014-present

Project Summary (2016-2017)

Elevated fish mercury levels in several lakes throughout the Dehcho and Sahtú regions of the Mackenzie Valley resulted in a series of food consumption advisories suggesting local residents limit their consumption of predatory fish from certain lakes. Furthermore, an advisory was placed on the consumption of kidneys and liver of moose from certain parts of the Northwest Territories. Therefore, a multi-year biomonitoring study is currently investigating the levels of contaminant exposure among participating First Nations communities. Building on the work already completed, in 2016-2017 human hair, urine, and blood sampling for contaminant biomonitoring will be implemented in up to five communities, and an additional six communities in 2017-2018. Surveys will also assess perceptions of contaminants, current food consumption patterns, and preferences for communication strategies. Public health messaging based upon Year 1 sampling as well as the results from risk perception and communication surveys, will begin in 2016 and will continue through to 2019. This work will incorporate a risk-benefit approach to promote the use of country food in order to improve nutrition and food security while lessening contaminant exposure among First Nations in the Mackenzie Valley.

Synopsis (2015-2016)

Abstract:

In this first year (of a 3-year project), we implemented biomonitoring research in one Northwest Territories community and consulted with seven additional communities, between November 2015 and February 2016. Building upon prior consultations in 2014-2015, our research team traveled to the first participating community (Jean Marie River First Nation, NT) for data and sample collection. With the assistance of a local research coordinator and nurse, we collected blood, urine, and/or hair samples from 22 participants. Participants also completed a questionnaire and two dietary surveys (24-hr Recall, Food Frequency Questionnaire). Additionally, our team traveled to and consulted with two Sahtú communities (Deline and Tulita) and five Dehcho communities (Hay River First Nation, Hay River Metis, West Point First Nation, Kakisa, Trout Lake, Fort Simpson) regarding the expansion of the project and their potential participation in 2016-2017. Data analysis of the Year 1 results (metals in blood/urine; POPs in blood; mercury in hair; dietary surveys) is currently underway. In collaboration with regional, territorial, and federal partners, results will be returned to Year 1 participating communities in fall 2016.

Key messages:

  • 22 participants from Jean Marie River First Nation, NT provided hair, blood, and/or urine samples for contaminant analyses
  • Year 1 samples are currently being analyzed for mercury (hair), metals and metalloids (hair, blood, urine), and POPs (blood)
  • Year 1 results will be returned to participating communities in fall 2016
  • Consultations with leaders and community members were held in Deline, Tulita, Trout Lake, Hay River, Kakisa, and Fort Simpson to discuss their potential participation in the biomonitoring project in 2016-2017

Synopsis (2014-2015)

Abstract:

For this pilot project, a tablet-based dietary survey for the characterization of traditional food consumption in the Northwest Territories was designed and evaluated. This electronic dietary survey was based upon a Food Frequency Questionnaire implemented by CINE scientists in the Dehcho Region in the 1990’s in order to promote consistency with previous research. In December 2015, our research team traveled to two communities (Kakisa, NT and Jean Marie River, NT) in the Dehcho Region of the Northwest Territories in order to discuss the adequacy of the survey as well as ways by which the survey could be improved. Most focus group participants were generally satisfied with the survey, commenting that they found tablet-interface intuitive and easy-to-use. The focus groups provided several suggestions for the survey, including the addition of more locally-relevant names and the clarification of typical preparation and cooking methods. Additionally, participants brought to our attention several traditional foods and plants that were missing from the survey (e.g.,, elk, white-tail deer, bison, high bush cranberries, spruce gum, rat root). Finally, focus group participants provided very useful details on the seasonal availability of particular food items. This electronic dietary survey, which was revised according to this valuable feedback, will be included within a contaminant biomonitoring project planned for the Northwest Territories in 2015-2018.

Key messages:

  • Following consultation at the Return to Country Food Workshop (August, 2014) workshop participants expressed a strong interest in conducting biomonitoring research in the Dehcho Region.
  • Community consultations were held in Kakisa, NT and Jean Marie River, NT in December 2014 to determine, if such a biomonitoring project should happen, what it should look like.
  • An electronic dietary survey was designed and evaluated through focus groups in the Dehcho Region.
  • This electronic dietary survey will be included within the biomonitoring research to be built off this pilot project.
 

top of page

 Report a problem
Date modified: