Levels and trends of contaminants in humans of the Arctic

Comparative review of One Health and Indigenous approaches to wildlife research in Inuit Nunangat

There is increasing interest in One Health and Indigenous methodologies and approaches in wildlife research, but they are not widely used research applications in the Arctic. Both approaches are wide in scope and originate from different knowledge systems but are often compared synonymously. We review the literature of overlap between the term One Health and Inuit Qaujimajatuqangit (Inuit Indigenous Knowledge) throughout Inuit Nunaat on wildlife research. Three databases (SCOPUS, Web of Science, and BIOSIS) were used to find English language articles and books within the bounds of Inuit Nunaat. While One Health and Inuit Qaujimajatuqangit research approaches share synergies, they are fundamentally disparate owing to their differences in epistemology, including views on the natural environment and wildlife management. We describe current examples of One Health being operationalized in Inuit Nunaat and identify potential to address larger and more complex questions about wildlife health, with examples from terrestrial and marine Arctic wildlife. Both Indigenous methodologies and One Health naturally have a human component at their core, which seamlessly lends itself to discussions on wildlife management, as human actions and regulations directly impact environment and wildlife health.

Analysis of chemical exposures in racial populations in Canada: An investigation based on the Canadian health measures survey

Despite demonstrated disparities in environmental chemical exposures by racial identity, no Canadian study has systematically assessed the feasibility of using a nationally representative dataset to examine differences in chemical concentrations by race. We assessed the feasibility and constraints of analysing chemical exposures in racial populations, including visible minorities and populations of Indigenous identity, using biomonitoring data collected through the Canadian Health Measures Survey (CHMS). Our primary objectives were to assess the ability to 1) generate geometric means and percentiles of chemical concentrations for racial populations by age or sex, 2) statistically compare concentrations among racial populations, and 3) calculate time trends of concentrations by race. We conducted these analyses for several priority chemicals: lead, cadmium, benzene, bisphenol A (BPA), and di(2-ethylhexyl) phthalate (DEHP). Survey participants self-identified as one of the following: White, Black, East and Southeast Asian, South Asian, Middle Eastern, Latin American, First Nations, Metis, and Inuit. Analyses were conducted for individual and combined cycles of the CHMS. Using data from the latest CHMS cycle in which each chemical was measured, we observed that sample sizes were sufficient to report geometric mean concentrations for all races except Inuit. Due to privacy considerations associated with small sample sizes, the 5th and 95th percentile concentrations could not be consistently reported for all racial populations in this analysis. While we were able to statistically compare concentrations among racial populations, the analysis was constrained by the limited number of statistical degrees of freedom available in a single CHMS cycle. Both of these constraints were alleviated by combining multiple cycles of data. The analysis of time trends was less subject to privacy and statistical limitations; we were able to calculate time trends of chemical concentrations for all racial populations. Our findings provide an important baseline for follow-up investigations of descriptive and etiological analyses of environmental chemical exposures and race in the CHMS.

Environmental contaminants in Arctic human populations: Trends over 30 years

INTRODUCTION

Arctic Monitoring and Assessment Programme (AMAP) monitors persistent organic pollutant (POP) levels in the Arctic populations and assesses health effects related to exposure to them. Many internationally regulated POPs persist in humans and biota, while new Emerging Contaminants of Arctic Concern (ECAC), many of which are unregulated, present additional challenges. Biomonitoring offers valuable insights into temporal trends within human matrices, revealing critical information not only about the efficacy of international regulations but also serving as an early warning system for exposure and risks for human health.

METHODS

Data analyzed in this study is aggregated data presented in the AMAP Human Health in the Arctic assessments, which provide data on contaminant concentrations measured in human matrices from adults, and children across various population studies conducted in the Arctic since the 1980 s. Linear regression analyses were used to assess trends of various POPs including organochlorine (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and per- and polyfluoroalkyl substances (PFAS), measured over time from the Arctic populations in Finland, Norway, Sweden, Denmark, Iceland, Canada and Alaska (USA).

RESULTS

Overall, decreasing trends were observed for PCBs and OCPs. Regulated PFAS showed decreasing trends, but increasing trends were observed for unregulated PFAS in certain populations. PBDEs showed decreasing or inconsistent trends in certain Arctic populations.

CONCLUSIONS

Decreasing trends are observed for legacy POPs, but the trends for new emerging contaminants are inconsistent. More focus is needed on biomonitoring the new emerging contaminants of concern in the Arctic and their implications on human health.

Non-invasive biomonitoring of polar bear feces can be used to estimate concentrations of metals of concern in traditional food

The Arctic faces increasing exposure to environmental chemicals such as metals, posing health risks to humans and wildlife. Biomonitoring of polar bears (Ursus maritimus) can be used to quantify chemicals in the environment and in traditional foods consumed by the Inuit. However, typically, these samples are collected through invasive or terminal methods. The biomonitoring of feces could be a useful alternative to the current metal monitoring method within the Arctic. Here, we aim to 1) quantify the relationship between concentrations of metals in the feces and tissues (muscle, liver, and fat) of polar bears using predictive modeling, 2) develop an easy-to-use conversion tool for use in community-based monitoring programs to non-invasively estimate contaminant concentrations in polar bears tissues and 3) demonstrate the application of these models by examining potential exposure risk for humans from consumption of polar bear muscle. Fecal, muscle, liver, and fat samples were harvested from 49 polar bears through a community-based monitoring program. The samples were analyzed for 32 metals. Exploratory analysis indicated that mean metal concentrations generally did not vary by age or sex, and many of the metals measured in feces were positively correlated with the internal tissue concentration. We developed predictive linear regression models between internal (muscle, liver, fat) and external (feces) metal concentrations and further explored the mercury and methylmercury relationships for utility risk screening. Using the cross-validated regression coefficients, we developed a conversion tool that contributes to the One Health approach by understanding the interrelated health of humans, wildlife, and the environment in the Arctic. The findings support using feces as a biomonitoring tool for assessing contaminants in polar bears. Further research is needed to validate the developed models for other regions in the Arctic and assess the impact of environmental weathering on fecal metal concentrations.

Sources of exposure to lead in Arctic and subarctic regions: a scoping review

Understanding lead exposure pathways is a priority because of its ubiquitous presence in the environment as well as the potential health risks. We aimed to identify potential lead sources and pathways of lead exposure, including long-range transport, and the magnitude of exposure in Arctic and subarctic communities. A scoping review strategy and screening approach was used to search literature from January 2000 to December 2020. A total of 228 academic and grey literature references were synthesised. The majority of these studies (54%) were from Canada. Indigenous people in Arctic and subarctic communities in Canada had higher levels of lead than the rest of Canada. The majority of studies in all Arctic countries reported at least some individuals above the level of concern. Lead levels were influenced by a number of factors including using lead ammunition to harvest traditional food and living in close proximity to mines. Lead levels in water, soil, and sediment were generally low. Literature showed the possibility of long-range transport via migratory birds. Household lead sources included lead-based paint, dust, or tap water. This literature review will help to inform management strategies for communities, researchers, and governments, with the aim of decreasing lead exposure in northern regions.

Human health risk assessment of heavy metals from meat and offal of reindeer and cow in the Far North of European Russia

AIMS

This study aimed to compare the concentrations of heavy metals in reindeer and cow meat and offal originating from the Nenets Autonomous Okrug, Northwestern Russia, and to assess the risk to the health of the indigenous population associated with heavy metal intake due to the consumption of reindeer and cow.

METHODS

Lead, cadmium, mercury, and arsenic concentrations were measured in 39 muscle, 15 liver, and 14 kidney samples from reindeer and 33, 18, and 12 corresponding samples from cow in 2014-2016 using atomic absorption spectrometry. Estimated daily intake of investigated heavy metals, hazard quotient, hazard index and cancer risk were calculated.

RESULTS

Mean cadmium and mercury concentrations in reindeer liver and kidney exceeded the maximum permissible levels for bovine animals. However, the estimated daily intakes of heavy metals through consumption of reindeer and cow meat and offal were lower than tolerable daily intakes. Hazard quotient and hazard index values for heavy metals in reindeer and cow samples were <1. Hazard index values were in descending order: reindeer kidney (0.389)>reindeer muscle (0.382)>cow muscle (0.088)>reindeer liver (0.051)>cow kidney (0.012)>cow liver (0.004). The cancer risk related to the consumption of reindeer and cow meat and offal did not exceed acceptable levels.

CONCLUSIONS

There is no human health risk associated with heavy metal intake due to the consumption of reindeer and cow meat and offal originating from the Nenets Autonomous Okrug.

Human health risk model for microplastic exposure in the Arctic region

Microplastics enriched with carcinogens like heavy metals, polycyclic aromatic hydrocarbons (PAHs), and their derivatives are ubiquitous in Arctic waters. They contaminate the local land and sea-based food sources, which is a significant health hazard. It is thus imperative to assess the risk posed by them to the nearby communities, which primarily rely on locally available food sources to meet their energy requirements. This paper proposes a novel ecotoxicity model to assess the human health risk posed by microplastics. The region's geophysical and environmental conditions affecting human microplastic intake, along with the human physiological parameters influencing biotransformation, are incorporated into the developed causation model. It investigates the carcinogenic risk associated with microplastic intake in humans via ingestion in terms of incremental excess lifetime cancer risk (IELCR). The model first evaluates microplastic intake and then uses reactive metabolites produced due to the interaction of microplastics with xenobiotic metabolizing enzymes to assess cellular mutations that result in cancer. All these conditions are mapped in an Object-Oriented Bayesian Network (OOBN) framework to evaluate IELCR. The study will provide a vital tool for formulating better risk management strategies and policies in the Arctic region, especially concerning Arctic Indigenous peoples.

An ecological approach to understanding Women's reproductive health and pregnancy decision making in Greenland

Using a community based participatory research framework and ecological systems theory we explored the experiences of reproductive health among Inuit women living in a remote Northwestern settlement in Greenland to understand the multiple diverse factors that influence their pregnancy outcomes. We conducted 15 in depth interviews with Inuit women between the ages of 19 and 45. Key factors influencing women's pregnancy decision making were: 1) precursors to pregnancy; 2) birth control use; 3) adoption and abortion; and 4) access to reproductive health care. Our results highlight the need to identify pathways through research, policy, health promotion, and health care practice that can support Inuit women in Greenland to be reproductively healthy and make informed decisions about pregnancy that resonate with their cultural beliefs as well as the realities of their everyday lives. We recommend the integration of cultural messaging into interdisciplinary approaches for preventive reproductive health care with women living in remote Arctic communities.

Prenatal exposure to persistent organic pollutants and metals and problematic child behavior at 3-5 years of age: a Greenlandic cohort study

High levels of persistent organic pollutants (POPs) and heavy metals are found in Arctic populations. POP and heavy metals are linked to impaired cognitive development. This study examined associations between prenatal POP and metals exposure and problematic child behavior using the Strength and Difficulties Questionnaire (SDQ). POPs and metals were measured in 102 pregnant Greenlandic women. During follow-up at 3–5 years, parents answered an assisted questionnaire including children’s SDQ scores. Associations were analyzed using linear and logistic regression analyses and adjusted for maternal plasma cotinine, educational level and age at delivery. In the adjusted analyses, the medium tertile of hexachlorobenzene (β = 3.06, p = 0.010), β-hexachlorocyclohexane (β = 3.58, p = 0.004) and trans-nonachlor (β = 2.06, p = 0.082) were positively associated with SDQ scores. The continuous cis-nonachlor (OR = 1.09, p = 0.079), dichloro-diphenyl-dichloroethylene (OR = 1.01, p = 0.077), trans-nonachlor (OR = 1.01, p = 0.091), and sum Organochlorine-Pesticides (OR = 1.00, p = 0.094) were positively associated with abnormal SDQ score and the continuous mirex (OR = 1.28, p = 0.096), oxychlordane (OR = 1.04, p = 0.066), and trans-nonachlor (OR = 1.02, p = 0.071) with abnormal hyperactivity score. We found no consistent evidence of associations between polychlorinated biphenyls, perfluoroalkylated substances and heavy metals and problematic behavior. Prenatal organochlorine pesticide exposure associated significantly with problematic behavior in 3–5 year old children.

Variation in biomarker levels of metals, persistent organic pollutants, and omega-3 fatty acids in association with genetic polymorphisms among Inuit in Nunavik, Canada

BACKGROUND

Biomarker measures of contaminant exposure and nutrient status can help increase understanding of the risks and benefits associated with the consumption of traditional foods by Inuit. While gene-environment and gene-nutrient interactions may help explain variations in biomarker measures, the role of genetic polymorphisms is largely understudied especially for vulnerable sub-populations.

OBJECTIVE

The aim of this study was to characterize the relationship between single nucleotide polymorphisms (SNPs) in key genes and blood concentrations of environmental chemicals and nutrients among Inuit.

METHODS

Blood samples from 665 individuals who participated in the Qanuippitaa Survey (Nunavik, Canada) in 2004 were analyzed for toxicants and nutrients. DNA was extracted and 140 SNPs in classes relevant to the toxicokinetics and/or toxicodynamics of the target contaminants and nutrients, and/or are involved in cardiovascular health and lipid metabolism were genotyped using the Sequenom iPLEX Gold platform.

RESULTS

Geometric means (μg/L) of mercury (Hg), cadmium (Cd), lead (Pb), DDE, PCB-153, and selenium (Se) were 11.1, 2.8, 39.9, 2.9, 1.1 and 301.2, respectively. Red blood cell membrane levels of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were 5.1%/total fatty acid (TFA) and 1.3%/TFA respectively. Out of 106 SNPs which met our inclusion criteria, biomarker levels for Hg, Cd, Pb, DDE, PCB-153, DHA, and EPA differed (p < 0.05) by genotype for 20, 13, 12, 19, 21, 9 and 8 SNPs, respectively. Following Bonferroni correction (p < 0.0005), only 9 SNPs remained significant (rs2274976 in MTHFR, rs174602 in FADS2, rs7115739 and rs74771917 in FADS3, rs713041 in GPX4, rs2306283 and rs4149056 in SLCO1B1, rs1885301 in ABCC2/MRP2, and rs4244285 in CYP2C19; 5 associated with Hg, 2 with Pb, 2 with DDE, 4 with PCB-153, 1 with DHA).

CONCLUSIONS

The findings suggest that polymorphisms in environmentally-responsive genes can influence biomarker levels of key toxicants and nutrients. While there are no immediate clinical or public health implications of these findings, we believe that such gene-environment and gene-nutrient studies provide a foundation that will inform and provide direction to future studies.

Climate Change and Enteric Infections in the Canadian Arctic: Do We Know What’s on the Horizon?

The Canadian Arctic has a long history with diarrheal disease, including outbreaks of campylobacteriosis, giardiasis, and salmonellosis. Due to climate change, the Canadian Arctic is experiencing rapid environmental transformation, which not only threatens the livelihood of local Indigenous Peoples, but also supports the spread, frequency, and intensity of enteric pathogen outbreaks. Advances in diagnostic testing and detection have brought to attention the current burden of disease due to Cryptosporidium, Campylobacter, and Helicobacter pylori. As climate change is known to influence pathogen transmission (e.g., food and water), Arctic communities need support in developing prevention and surveillance strategies that are culturally appropriate. This review aims to provide an overview of how climate change is currently and is expected to impact enteric pathogens in the Canadian Arctic.

Essential and non-essential elements in biological samples of inhabitants residing in Nenets Autonomous Okrug of the Russian Arctic

Exposure of Arctic residents to environmental pollutants is an emerging public health problem receiving little global attention. The objective of this study was to assess whole blood concentrations of nine selected essential (Co, Cu, Mn, Se, Zn) and non-essential (As, Cd, Hg, Pb) elements among Nenets and non-Nenets adult residents of the Nenets Autonomous Okrug (NAO) living in seven coastal and inland settlements. Urine was collected in two settlements for assessment of iodine status. Altogether 297 whole blood and 68 urine samples were analysed by inductively coupled mass spectrometry and the accuracy of the measurements was assessed by use of human whole blood and urine quality control materials. Several essential and non-essential showed significant variations in whole blood concentrations characterized by gender, population group and locality. Cd levels among non-Nenets non-smokers (0.19 µg/L) indicated a dietary intake at a natural global background level. Hg concentrations in whole blood show that not more than 10% of women in the fertile age had a Hg intake above the EFAS's recommendation. The Pb concentrations were in the range of, or partly exceeding reference values for increased risk of nephrotoxicity, and there is a need for a continued effort to reduce Pb exposure among the population groups in NAO. With high prevalence of obesity among the Nenets and non-Nenets population, a high prevalence of Fe-deficiency among menstruating women (<50 years) (37.2%) and a lower I status than recommended by WHO, these nutritional dependent components deserve further attention.

MercuNorth - monitoring mercury in pregnant women from the Arctic as a baseline to assess the effectiveness of the Minamata Convention

Exposure to mercury (Hg) is a global concern, particularly among Arctic populations that rely on the consumption of marine mammals and fish which are the main route of Hg exposure for Arctic populations.The MercuNorth project was created to establish baseline Hg levels across several Arctic regions during the period preceding the Minamata Convention. Blood samples were collected from 669 pregnant women, aged 18-44 years, between 2010 and 2016 from sites across the circumpolar Arctic including Alaska (USA), Nunavik (Canada), Greenland, Iceland, Norway, Sweden, Northern Lapland (Finland) and Murmansk Oblast (Russia). Descriptive statistics were calculated, multiple pairwise comparisons were made between regions, and unadjusted linear trend analyses were performed.Geometric mean concentrations of total Hg were highest in Nunavik (5.20 µg/L)  and Greenland (3.79 µg/L), followed by Alaska (2.13 µg/L), with much lower concentrations observed in the other regions (ranged between 0.48 and 1.29 µg/L). In Nunavik, Alaska and Greenland, blood Hg concentrations have decreased significantly since 1992, 2000 and 2010 respectively with % annual decreases of 4.7%, 7.5% and 2.7%, respectively.These circumpolar data combined with fish and marine mammal consumption data can be used for assessing long-term Hg trends and the effectiveness of the Minamata Convention.

Human biomonitoring results of contaminant and nutrient biomarkers in Old Crow, Yukon, Canada

Several large-scale human biomonitoring projects have been conducted in Canada, including the Canadian Health Measures Survey (CHMS) and the First Nations Biomonitoring Initiative (FNBI). However, neither of these studies included participants living in the Yukon. To address this data gap, a human biomonitoring project was implemented in Old Crow, a fly-in Gwich'in community in the northern Yukon. The results of this project provide baseline levels of contaminant and nutrient biomarkers from Old Crow in 2019. Samples of hair, blood, and/or urine were collected from approximately 44% of community residents (77 of 175 adults). These samples were analyzed for contaminants (including heavy metals and persistent organic pollutants (POPs)), and nutrients (including trace elements and omega-3 fatty acids). Levels of these analytes were compared to health-based guidance values, when available, and results from other human biomonitoring projects in Canada. Levels of lead (GM 0.64 μg/g creatinine in urine/24 μg/L blood), cadmium (GM 0.32 μg/g creatinine in urine/0.85 μg/L blood), and mercury (GM < LOD in urine/0.76 μg/L blood/0.31 μg/g hair) were below select health-based guidance values for more than 95% of participants. However, compared to the general Canadian population, elevated levels of some contaminants, including lead (approximately 2× higher), cobalt (approximately 1.5× higher), manganese (approximately 1.3× higher), and hexachlorobenzene (approximately 1.5× higher) were observed. In contrast, levels of other POPs, including insecticides such as dichlorodiphenyltrichloroethane (DDT), its metabolite, dichlorodiphenyldichloroethylene (DDE), and polychlorinated biphenyls (PCBs) were similar to, or lower than, those reported in the general Canadian population. This study can be used along with future biomonitoring programs to evaluate the effectiveness of international initiatives designed to reduce the contaminant burden in the Arctic, including the Stockholm Convention and the Minamata Convention. Regionally, this project complements environmental monitoring being conducted in the region, informing local and regional traditional food consumption advisories.

Time Trend of Persistent Organic Pollutants and Metals in Greenlandic Inuit during 1994-2015

Persistent organic pollutants (POPs), including polychlorinated biphenyls (PCBs), organchlorine pesticides and perfluoroalkylated substances (PFASs) and heavy metals bioaccumulate in the marine food chain in the Arctic regions, and thus, the Greenlandic population has a higher body burden due to relatively high intake of marine mammals. We assessed the temporal trend for POPs, including PCB 153; 1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene (p,p'-DDE); oxychlordane; six PFASs; mercury; lead and selenium in Inuit from Ilulissat, Nuuk, and across Greenland (including thirteen towns/districts), from 1994 to 2015. Data showed a significant annual decrease of 6.85-8.61% for PCB153, 6.67-8.61% for p,p'-DDE, 6.11-9.52% for oxychlordane, 5.92-6.76% for mercury and 6.48-9.43% for lead in Inuit women from Nuuk, Ilulissat, and across thirteen Greenlandic districts. The blood selenium level of all Greenlandic women increased 1.01% annually, while the trend direction was negative for Nuuk women. A similar pattern was seen for men across Greenland, with a yearly decrease of 11.3% for PCB 153, 8.61% for p,p'-DDE, 15.6% for oxychlordane, 13.1% for mercury and 12.2% for lead. Perfluorooctane sulfonate, perfluorohexane sulfonate and perfluorooctanoic acid significantly decreased 5.82-11.7% annually for both women and men across Greenland. For perfluorononanoic acid, perfluorodecanoic acid and perfluoroundecanoic acid, we observed an increasing trend for women across Greenland. In conclusion, there was a decreasing trend of the regulated POPs and metals but a potential increasing trend of the nonregulated PFASs in the Greenlandic population between 1994 and 2015. The continuing biomonitoring of contaminants of concern is important to protect the Arctic population heath.

A first assessment of microplastics and other anthropogenic particles in Hudson Bay and the surrounding eastern Canadian Arctic waters of Nunavut

Microplastics are a globally ubiquitous contaminant, invading the most remote regions, including the Arctic. To date, our understanding of the distribution and sources of microplastics in the Arctic is limited but growing. This study aims to advance our understanding of microplastics in the Arctic. Surface water, zooplankton, sediment, and snow samples were collected from Hudson Bay to north Baffin Bay onboard the CCGS Amundsen from July to August 2017. Samples were examined for microplastics, which were chemically identified via Raman spectroscopy for surface water and zooplankton and Fourier transform infrared spectroscopy for sediment. We found that 90% of surface water and zooplankton samples, and 85% of sediment samples, contained microplastics or other anthropogenic particles. Mean anthropogenic particle concentrations, which includes microplastics, were 0.22 ± 0.23 (per litre) for surface water, 3.51 ± 4.00 (per gram) for zooplankton, and 1.94 ± 4.12 (per gram) for sediment. These concentrations were not related to the human populations upstream, suggesting that microplastic contamination in the Arctic is from long-range transport. Overall, this study highlights the presence of microplastics across the eastern Canadian Arctic, in multiple media, and offers evidence of long-range transport via ocean and atmospheric currents. Further research is needed to better understand sources, distribution, and effects to Arctic ecosystems.

Maternal folic acid supplementation does not counteract the deleterious impact of prenatal exposure to environmental pollutants on lipid homeostasis in male rat descendants

Prenatal exposure to persistent organic pollutants (POPs) has been associated with the development of metabolic syndrome-related diseases in offspring. According to epidemiological studies, father’s transmission of environmental effects in addition to mother’s can influence offspring health. Moreover, maternal prenatal dietary folic acid (FA) may beneficially impact offspring health. The objective is to investigate whether prenatal FA supplementation can overcome the deleterious effects of prenatal exposure to POPs on lipid homeostasis and inflammation in three generations of male rat descendants through the paternal lineage. Female Sprague-Dawley rats (F0) were exposed to a POPs mixture (or corn oil) +/− FA supplementation for 9 weeks before and during gestation. F1 and F2 males were mated with untreated females. Plasma and hepatic lipids were measured in F1, F2, and F3 males after 12-h fast. Gene expression of inflammatory cytokines was determined by qPCR in epididymal adipose tissue. In F1 males, prenatal POPs exposure increased plasma lipids at 14 weeks old and hepatic lipids at 28 weeks old and prenatal FA supplementation decreased plasma total cholesterol at 14 weeks old. Prenatal POPs exposure decreased plasma triglycerides at 14 weeks old in F2 males. No change was observed in inflammatory markers. Our results show an impact of the paternal lineage on lipid homeostasis in rats up to the F2 male generation. FA supplementation of the F0 diet, regardless of POPs exposure, lowered plasma cholesterol in F1 males but failed to attenuate the deleterious effects of prenatal POPs exposure on plasma and hepatic lipids in F1 males.

Pregnant Inuit Women's Exposure to Metals and Association with Fetal Growth Outcomes: ACCEPT 2010⁻2015

Environmental contaminants such as heavy metals are transported to the Arctic regions via atmospheric and ocean currents and enter the Arctic food web. Exposure is an important risk factor for health and can lead to increased risk of a variety of diseases. This study investigated the association between pregnant women's levels of heavy and essential metals and the birth outcomes of the newborn child. This cross-sectional study is part of the ACCEPT birth cohort (Adaption to Climate Change, Environmental Pollution, and dietary Transition) and included 509 pregnant Inuit women ≥18 years of age. Data were collected in five Greenlandic regions during 2010⁻2015. Population characteristics and birth outcomes were obtained from medical records and midwives, respectively, and blood samples were analyzed for 13 metals. Statistical analysis included one-way ANOVA, Spearman's rho, and multiple linear and logistic regression analyses. The proportion of current smokers was 35.8%. The levels of cadmium, chromium, and nickel were higher compared to reported normal ranges. Significant regional differences were observed for several metals, smoking, and parity. Cadmium and copper were significantly inversely related to birth outcomes. Heavy metals in maternal blood can adversely influence fetal development and growth in a dose⁻response relationship. Diet and lifestyle factors are important sources of toxic heavy metals and deviant levels of essential metals. The high frequency of smokers in early pregnancy is of concern, and prenatal exposure to heavy metals and other environmental contaminants in the Greenlandic Inuit needs further research.

Responding to Climate and Environmental Change Impacts on Human Health via Integrated Surveillance in the Circumpolar North: A Systematic Realist Review

Environments are shifting rapidly in the Circumpolar Arctic and Subarctic regions as a result of climate change and other external stressors, and this has a substantial impact on the health of northern populations. Thus, there is a need for integrated surveillance systems designed to monitor the impacts of climate change on human health outcomes as part of broader adaptation strategies in these regions. This review aimed to identify, describe, and synthesize literature on integrated surveillance systems in Circumpolar Arctic and Subarctic regions, that are used for research or practice. Following a systematic realist review approach, relevant articles were identified using search strings developed for MEDLINE® and Web of Science™ databases, and screened by two independent reviewers. Articles that met the inclusion criteria were retained for descriptive quantitative analysis, as well as thematic qualitative analysis, using a realist lens. Of the 3431 articles retrieved in the database searches, 85 met the inclusion criteria and were analyzed. Thematic analysis identified components of integrated surveillance systems that were categorized into three main groups: structural, processual, and relational components. These components were linked to surveillance attributes and activities that supported the operations and management of integrated surveillance. This review advances understandings of the distinct contributions of integrated surveillance systems and data to discerning the nature of changes in climate and environmental conditions that affect population health outcomes and determinants in the Circumpolar North. Findings from this review can be used to inform the planning, design, and evaluation of integrated surveillance systems that support evidence-based public health research and practice in the context of increasing climate change and the need for adaptation.

Polychlorinated biphenyls (PCBs) as sentinels for the elucidation of Arctic environmental change processes: a comprehensive review combined with ArcRisk project results

Polychlorinated biphenyls (PCBs) can be used as chemical sentinels for the assessment of anthropogenic influences on Arctic environmental change. We present an overview of studies on PCBs in the Arctic and combine these with the findings from ArcRisk-a major European Union-funded project aimed at examining the effects of climate change on the transport of contaminants to and their behaviour of in the Arctic-to provide a case study on the behaviour and impact of PCBs over time in the Arctic. PCBs in the Arctic have shown declining trends in the environment over the last few decades. Atmospheric long-range transport from secondary and primary sources is the major input of PCBs to the Arctic region. Modelling of the atmospheric PCB composition and behaviour showed some increases in environmental concentrations in a warmer Arctic, but the general decline in PCB levels is still the most prominent feature. 'Within-Arctic' processing of PCBs will be affected by climate change-related processes such as changing wet deposition. These in turn will influence biological exposure and uptake of PCBs. The pan-Arctic rivers draining large Arctic/sub-Arctic catchments provide a significant source of PCBs to the Arctic Ocean, although changes in hydrology/sediment transport combined with a changing marine environment remain areas of uncertainty with regard to PCB fate. Indirect effects of climate change on human exposure, such as a changing diet will influence and possibly reduce PCB exposure for indigenous peoples. Body burdens of PCBs have declined since the 1980s and are predicted to decline further.

Seasonal variation and source analysis of persistent organic pollutants in the atmosphere over the western Tibetan Plateau

Over the past few decades, the Tibetan Plateau (TP) region has become gradually contaminated by persistent organic pollutants (POPs). The picture regarding POPs is clear in the central and southern parts of the TP; however, few observational campaigns have focused on the western TP. To clarify the concentrations, seasonal trends and source regions of POPs in the western TP, a first study of POPs in Muztagh Ata (westerly region) and a long-term (5 years) monitoring program in Ngari (transect region influenced by both the Indian monsoon and westerly climate) were conducted. Except for hexachlorobenzene (HCB) and polychlorinated biphenyls (PCBs), relatively low POP levels were observed in the western TP. In Muztagh Ata, dichlorodiphenyltrichloroethanes (DDTs) showed higher concentrations in winter and lower ones in summer, whereas at Ngari, higher DDTs and hexachlorocyclohexanes (HCHs) concentrations were observed in summer as compared with winter. Source diagnosis indicated that Xinjiang and central Asia were the main source regions for POPs in Muztagh Ata and that westerly winds play a key role in transporting POPs from central Asia. No correlation was found between the height of the atmospheric boundary layer and the concentrations of POPs over the TP.