Exposure to benzene, toluene and polycyclic aromatic hydrocarbons in Nunavimmiut aged 16 years and over (Nunavik, Canada) - Qanuilirpitaa 2017 survey.

There are numerous volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbons (PAHs) that Inuit may be exposed to from combustion, cooking, heating, vehicle exhaust, active and passive smoking and other local sources of contaminants such as oil spills or open-air burning in landfills. To better assess the levels of exposure to these non-persistent chemicals, we measured a suite of benzene, toluene (two VOCs) and PAHs metabolites in pooled urine samples from youth and adults aged 16 years old and over who participated in the Qanuilirpitaa? 2017 Inuit Health Survey (Q2017), a population health survey conducted in Nunavik. A cost-effective pooling strategy was established and 30 different pools from individual urine samples (n = 1266) were created by grouping individual urine samples by sex, age groups and regions. To assess smoking and exposure to second-hand smoke, cotinine levels were measured in individual urine samples. We found that benzene, toluene, all detected PAHs metabolites and cotinine levels were significantly higher in Q2017 compared to adults in the Canadian Health Measure Survey Cycle 4 (2014-2015) or the general U.S population (2015-2016). Moreover, mean levels of one benzene metabolite, S-phenylmercapturic acid, and several PAHs metabolites, 1-naphthol, 2-and 3-hydroxyfluorene, and 4- and 9-hydroxyphenanthrene, known to be associated with smoking habits, were higher in Q2017 compared to reference values (RV95) established for non-smokers in the general Canadian population. Furthermore, benzene and PAHs metabolites were all correlated with cotinine levels. Our results suggest that the high smoking prevalence in Nunavik is an important contributor to the elevated benzene and PAHs exposure. Other local sources may add to that exposure, although we were not able to account for their contribution. These data highlight the importance of regional and community efforts for reducing smoking and to encourage smoke-free homes in Nunavik, while continuing to investigate and reduce other possible local sources of exposure to benzene, toluene and PAHs.

Characterizing Important Dietary Exposure Sources of Perfluoroalkyl Acids in Inuit Youth and Adults in Nunavik Using a Feature Selection Tool.

BACKGROUND: Previous studies have identified the consumption of country foods (hunted/harvested foods from the land) as the primary exposure source of perfluoroalkyl acids (PFAA) in Arctic communities. However, identifying the specific foods associated with PFAA exposures is complicated due to correlation between country foods that are commonly consumed together. METHODS: We used venous blood sample data and food frequency questionnaire data from the Qanuilirpitaa? ("How are we now?") 2017 (Q2017) survey of Inuit individuals ≥16 y of age residing in Nunavik (n=1,193). Adaptive elastic net, a machine learning technique, identified the most important food items for predicting PFAA biomarker levels while accounting for the correlation among the food items. We used generalized linear regression models to quantify the association between the most predictive food items and six plasma PFAA biomarker levels. The estimates were converted to percent changes in a specific PFAA biomarker level per standard deviation increase in the consumption of a food item. Models were also stratified by food type (market or country foods). RESULTS: Perfluorooctanesulfonic acid (PFOS), perfluorodecanoic acid (PFDA), and perfluoroundecanoic acid (PFUnDA) were associated with frequent consumption of beluga misirak (rendered fat) [14.6%; 95% confidence interval (CI): 10.3%, 18.9%; 14.6% (95% CI: 10.1%, 19.0%)], seal liver [9.3% (95% CI: 5.0%, 13.7%); 8.1% (95% CI: 3.5%, 12.6%)], and suuvalik (fish roe mixed with berries and fat) [6.0% (95% CI: 1.3%, 10.7%); 7.5% (95% CI: 2.7%, 12.3%)]. Beluga misirak was also associated with higher concentrations of perfluorohexanesulphonic acid (PFHxS) and perfluorononanoic acid (PFNA), albeit with lower percentage changes. PFHxS, perfluorooctanoic acid (PFOA), and PFNA followed some similar patterns, with higher levels associated with frequent consumption of ptarmigan [6.1% (95% CI: 3.2%, 9.0%); 5.1% (95% CI: 1.1%, 9.1%); 5.4% (95% CI: 1.8%, 9.0%)]. Among market foods, frequent consumption of processed meat and popcorn was consistently associated with lower PFAA exposure. CONCLUSIONS: Our study identifies specific food items contributing to environmental contaminant exposure in Indigenous or small communities relying on local subsistence foods using adaptive elastic net to prioritize responses from a complex food frequency questionnaire. In Nunavik, higher PFAA biomarker levels were primarily related to increased consumption of country foods, particularly beluga misirak, seal liver, suuvalik, and ptarmigan. Our results support policies regulating PFAA production and use to limit the contamination of Arctic species through long-range transport. https://doi.org/10.1289/EHP13556.

Plasma concentrations of perfluoroalkyl acids and their determinants in youth and adults from Nunavik, Canada.

Perfluoroalkyl acids (PFAAs), a subset of per- and poly-fluoroalkyl substances (PFAS), are environmentally stable, mobile and bioaccumulative compounds. This leads to high concentrations in wildlife species essential to the cultural identity and subsistence of Arctic populations. Our objective was to characterize the distribution and exposure determinants of PFAAs among Nunavik Inuit adults. The study included up to 1322 Nunavik residents aged 16-80 years who participated in the Qanuilirpitaa? 2017 Nunavik Inuit Health Survey (Q2017). Plasma concentrations were compared to those the general Canadian population using data from the Canadian Health Measures Survey Cycle 5 (2016-2017). Associations between plasma concentrations of nine PFAAs, determined by liquid chromatography-tandem mass spectrometry, and sociodemographic factors and traditional activity participation were examined using multiple linear regression models. Overall exposure to PFAAs was twice as high compared to the general Canadian population and less regulated perfluorononanoic acid (PFNA) and perfluoroundecanoic acid (PFUnDA) concentrations were 7-fold higher, and perfluorodecanoic acid (PFDA) concentrations were 4-fold higher. Males had higher concentrations of perfluorooctanoic acid (PFOA) and perfluorohexane sulfonate (PFHxS), whereas females had higher concentrations of PFDA and PFUnDA. PFAAs concentrations increased with age and were highest among those aged 60+ years. PFNA and PFOA concentrations followed a J-shaped pattern: those aged 16-29 years had higher concentrations than those aged 20-29 and 30-39 years. Ungava Bay generally had lower concentrations of all PFAAs congeners compared to Hudson Bay and Hudson Strait, with the exception of PFNA, which tended to have the lowest concentration in Hudson Strait. PFAAs concentrations were highly associated with hunting activity, omega-3 polyunsaturated fatty acids, and drinking water from environmental sources. The results highlight the importance of characterizing PFAAs exposure sources in Arctic communities and provide further evidence for the long-range transport of long-chain PFAAs and their precursors that necessitate international action.

Cardiometabolic health and per and polyfluoroalkyl substances in an Inuit population.

INTRODUCTION: The cardiometabolic health status of Inuit in Nunavik has worsened in the last thirty years. The high concentrations of perfluoroalkyl acids (PFAAs) may be contributing to this since PFAAs have been linked with hypercholesterolemia, diabetes, and high blood pressure. The aim of this study was to examine the association between a PFAAs mixture and lipid profiles, Type II diabetes, prediabetes, and high blood pressure in this Inuit population. METHODS: We included 1212 participants of the Qanuilirpitaa? 2017 survey aged 16-80 years. Two mixture models (quantile g-computation and Bayesian Kernel Machine Regression (BKMR)) were used to investigate the associations between six PFAAs (PFHxS, PFOS, PFOA and three long-chain PFAAs (PFNA, PFDA and PFUnDA)) with five lipid profiles and three cardiometabolic outcomes. Non-linearity and interaction between PFAAs were further assessed. RESULTS: An IQR increase in all PFAAs congeners resulted in an increase in total cholesterol (ß 0.15, 95% confidence interval (CI) 0.06, 0.24), low-density lipoprotein cholesterol (LDL) (ß 0.08, 95% CI 0.01, 0.16), high-density lipoprotein cholesterol (HDL) (ß 0.04, 95% CI 0.002, 0.08), apolipoprotein B-100 (ß 0.03, 95% CI 0.004, 0.05), and prediabetes (OR 1.80, 95% CI 1.11, 2.91). There was no association between PFAAs and triglycerides, diabetes, or high blood pressure. Long-chain PFAAs congeners were the main contributors driving the associations. Associations were largely linear, and there was no evidence of interaction between the PFAAs congeners. CONCLUSIONS: Our study provides further evidence of increasing circulating lipids with increased exposure to PFAAs. The increased risk of prediabetes points to the influence of PFAAs on potential clinical outcomes. International regulation of PFAAs is essential to curb PFAAs exposure and related health effects in Arctic communities.

Associations between dietary profiles and perfluoroalkyl acids in Inuit youth and adults.

BACKGROUND: Perfluoroalkyl acids (PFAAs), a subset of perfluoroalkyl substances (PFAS), are synthetic chemicals used in industrial and consumer applications. They are exceptionally stable and highly mobile in the environment, and were detected in high concentrations in Arctic wildlife and Nunavik Inuit. The study's objective was to study the association between dietary profiles in Nunavik and plasma PFAAs concentrations. METHODS: The study used data from the Qanuilirpitaa? 2017 Nunavik Inuit Health Survey (Q2017) (N = 1172) on Inuit adults aged 16-80 years. Nine PFAAs congeners were measured in plasma samples (six were detected). Dietary profiles were identified using latent profile analysis. Two sets of dietary profiles were included; the first included market (store-bought) and country foods (harvested/hunted from the land), and the second included only country foods. Multiple linear regression models regressed log-transformed PFAAs concentrations against the dietary profiles, adjusting for sociodemographic variables. RESULTS: We identified statistically significant 24.54-57.55 % increases in all PFAAs congeners (PFOA, PFNA, PFDA, PFUnDA, PFHxS, and PFOS) in the dietary profile defined by frequent country food consumption compared to the dietary profile defined by frequent market food consumption. Individuals defined by low consumption of foods (related to food insecurity) had higher concentrations of six PFAAs compared to individuals with frequent market food consumption. The associations were stronger with profiles defined by more frequent country food consumption, and particularly those with increased marine mammal consumption. PFDA, PFUnDA, and PFOS were particularly associated with high country food consumption frequency, such that their concentrations increased by approximately 67-83 % compared to those reporting no or very little consumption of any country foods. CONCLUSIONS: Increased country food consumption was strongly associated with higher PFAAs concentrations, particularly PFOS, PFDA, and PFUnDA. The results provide further evidence that the quality of country foods is being threatened by PFAAs contamination. Additional national and international regulations are required to protect the Arctic and its inhabitants from these pollutants.

Non-persistent exposures from plasticizers or plastic constituents in remote Arctic communities: a case for further research.

BACKGROUND: Persistent organic pollutant exposures are well-documented in the Arctic, but fewer studies examined non-persistent chemicals, despite increased market food and consumer product consumption. OBJECTIVE: To measure phenol, paraben, phthalate, and alternative plasticizer concentrations in Inuit adults. METHODS: The study included 30 pooled urine samples from Qanuilirpitaa? 2017 Nunavik Inuit Health Survey (Q2017) participants. Creatinine-adjusted geometric mean concentrations (GM) and 95% confidence intervals (CI) were compared across sex, age, and regions, and compared to those in the Canadian Health Measures Survey (CHMS) and the First Nations Biomonitoring Initiative (FNBI). RESULTS: Q2017 bisphenol-A concentrations were double the CHMS 2018-2019 concentrations [GM (95% CI): 1.98 (1.69-2.31) versus 0.71 (0.60-0.84) µg/g creatinine], but in line with FNBI [1.74 (1.41-2.13) µg/g creatinine]. Several phthalate concentrations were higher in Q2017 versus CHMS, particularly monobenzyl phthalate, which was was 19-fold higher in Q2017 versus CHMS 2018-2019 [45.26 (39.35-52.06) versus 2.4 (2.0-2.9) µg/g creatinine] and four-fold higher than FNBI. There were also four-fold higher concentrations of the two alternate plasticizer 2,2,4-trimethyl-1,3-pentanediol diisobutyrate (TIXB) metabolites in Q2017 compared to CHMS 2018-2019. Women and people living in Ungava Bay had generally higher concentrations of non-persistent chemicals. SIGNIFICANCE: The results suggest higher concentrations of certain non-persistent chemicals in Inuit versus the general Canadian population. IMPACT: Few studies have explored non-persistent chemical distributions in Northern communities, despite the increasing consumer product and market food consumption. We analyzed 30 pooled samples from the Qanuilirpitaa? Nunavik Inuit Health Survey 2017 to assess exposures to common plasticizes and plastic constituents and compare their levels with the general Canadian population and First Nation groups. We observed particularly higher levels of bisphenol-A, of monobenzyl phthalate, and of two 2,2,4-trimethyl-1,3-pentanediol diisobutyrate (TXIB) metabolites among Nunavimmiut compared to the general Canadian population, notably among women and Ungava Bay residents. Larger studies are required to confirm our findings and identify potential adverse health effects from these exposures.

Seasonal variations in exposure to methylmercury and its dietary sources among pregnant Inuit women in Nunavik, Canada.

Among populations living in close connection with the sea, rivers and lakes for subsistence, diet varies according to local monthly wildlife species availability and food preferences. This may lead to variations in methylmercury (MeHg) exposure over a year, although no biomonitoring studies have documented this issue in Circumpolar populations, the most exposed to international Hg emissions. Our aim was to characterize seasonal variations in MeHg exposure among pregnant Inuit women from Nunavik and to identify country foods responsible for these variations. Between October 2016 and March 2017, 97 participants were recruited. Blood mercury (Hg) was tested and hair Hg was measured by centimeter as a surrogate for monthly MeHg exposure over the past year. Latent class growth analysis was conducted to identify groups of pregnant women with similar hair Hg monthly trajectories. Country foods consumption was documented by season. Seasonal daily intakes of MeHg were estimated based on concentrations in country foods. Retrospective monthly hair Hg analyses revealed that MeHg exposure was lowest in winter, and highest in summer and early fall months. Three latent classes (groups) of pregnant women with similar trajectories of monthly hair Hg variations were identified: high (n = 20, 21%), moderate (n = 38, 41%) and low variation (n = 35, 38%). Beluga meat was the country food contributing to most of daily MeHg intake, primarily during summer and fall, and was the only one associated with the odds of being classified into moderate and high variation groups (OR 95% CI: 1.19 [1.01-1.39] and 1.25 [1.04-1.50]). These findings underscore the importance of monthly variations in exposure to MeHg due to the seasonality of local foods consumed and responsible for elevated MeHg exposure. Further studies critically need to understand local diet fluctuations over a year to adequately assess MeHg exposure, adopt timely preventive interventions and evaluate the effectiveness of the Minamata Convention.

Perfluoroalkyl acids in pregnant women from Nunavik (Quebec, Canada): Trends in exposure and associations with country foods consumption.

BACKGROUND: Perfluoroalkyl acids (PFAAs) are persistent and ubiquitous environmental contaminants that potentially disrupt endocrine system functions. While some PFAAs (perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA)) are regulated, currently used fluorotelomer alcohols (FTOHs) can be transported to the Arctic and are degraded in a number of PFAAs which biomagnify in Arctic wildlife (e.g. perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUdA)). OBJECTIVES: From 2004 to 2017, 279 pregnant Inuit women were recruited as part of biomonitoring projects in Nunavik. Our goal was to evaluate: (i) time-trends in plasma/serum PFAAs levels in pregnant Nunavimmiut women between 2004 and 2017; (ii) compare plasma/serum PFAAs levels in Nunavimmiut women in 2016-2017 to those measured in women of childbearing age in the Canadian Health Measure Survey (CHMS); and (iii) evaluate the associations of PFAAs levels with the consumption of country foods and pregnancy and maternal characteristics during pregnancy in the 97 participants recruited in 2016-2017. METHODS: Individual blood sample were collected for serum or plasma PFAAs (PFOS, PFOA, pentafluorobenzoic acid (PFBA), perfluorohexanoic acid (PFHxA), perfluorobutanesulfonic acid (PFBS), perfluorohexane-1-sulfonic acid (PFHxS), PFNA, PFDA, PFUdA) analyses. Socio-demographic data, pregnancy and maternal characteristics and country foods consumption were documented using a questionnaire. Omega-3 and -6 polyunsaturated fatty acids (PUFA) were measured in red blood cell membranes and their ratio used as a biomarker of marine country foods consumption. Time-trends in PFAAs levels were evaluated using ANCOVA models adjusted for relevant co-variables. Serum/plasma levels of PFAAs in the 97 pregnant women aged 16 to 40 years old and recruited in 2016-2017 were compared to those measured in women aged 18 to 40 years old from the CHMS cycle 5 (2016-2017) using the geometric means (GM) and 95% confidence intervals (95% CI). Multivariate regression analyses were performed to examine associations between concentrations of PFAAs and country foods consumption data. RESULTS: Statistically-significant downward time trends were noted for concentrations of PFOS, PFOA and PFHxS in pregnant Nunavik women between 2004 and 2017. Conversely, between 2011 and 2016-2017, PFNA, PFDA and PFUdA maternal serum levels increased by 19, 13 and 21% respectively. Among participants in 2016-2017, mean concentrations for PFNA (GM: 2.4 µg/L), PFDA (0.53 µg/L) and PFUdA (0.61 µg/L) were higher than those measured in women aged 18-40 years old in the Cycle 5 (2016-2017) of the CHMS. PFOA (0.53 µg/L) and PFHxS (0.26 µg/L) were lower than in CHMS, whereas PFBA, PFHxA and PFBS were not detected in 2016-2017. Ratios of serum/plasma levels of PFNA/PFOA, PFNA/PFOS, PFNA/PFHxS and PFUdA/PFDA were significantly higher in the 97 pregnant women from Nunavik recruited in 2016-2017 compared to CHMS, highlighting their distinct exposure profile. In multivariate models, PFHxS, PFOS, PFNA, PFDA and PFUdA levels in 2016-2017 were strongly associated with the omega-3/omega-6 PUFA ratio, indicating a positive association between marine country foods consumption and higher exposure to PFAAs. CONCLUSIONS: The exposure of pregnant women to long-chain PFAAs (PFNA, PFDA and PFUdA) increased from 2004 to 2017 in Nunavik. Associations noted between PFAAs levels and the omega-3/omega-6 ratio highlights the importance of implementing additional strict regulations on PFAAs and their precursors to protect the high nutritional quality and cultural importance of country foods in Nunavik.

Risk and prevention of meningococcal disease among education workers: A review.

The aims of the present study were to review the risk of invasive meningococcal disease (IMD) among education workers, particularly pregnant women, and to evaluate preventive measures, in a context of endemicity, outbreak or epidemic as observed in the province of Quebec. The literature was reviewed and persons in charge of IMD surveillance in France, Quebec, the United Kingdom and the United States were interviewed. Surveys of asymptomatic carriage of Neisseria meningitidis show that transmission among students is higher than transmission between students and teachers. IMD incidence among education workers was analyzed in Cheshire (United Kingdom) in the period from 1997 to 1999, and the results indicated a risk six times higher than that in the general population. Overestimation of the magnitude of the risk is possible because the analysis focused on a cluster. None of the population-based studies of IMD mentioned a risk of secondary cases among education workers. Six IMD cases in education workers were identified in five clusters in schools in the United Kingdom, but not in the other countries. There is no epidemiological study on IMD risk among pregnant women, and this factor was not mentioned in any published review of IMD. Immunization of education workers at the beginning of their employment, using serogroup C glycoconjugate vaccine or a combined A, C, W-135, and Y conjugate vaccine (still under development), could reduce IMD risk, but the cost effectiveness of this measure should be evaluated. The societal benefit of excluding pregnant women from the work place during an outbreak seems to be very low, even if disease risk could be decreased for this specific group. When chemoprophylaxis is indicated for the control of an outbreak in an educational setting, treatment should be offered both to students and teachers in the group at risk.