Exposure to perfluoroalkyl substances (PFAS) and associations with thyroid parameters in First Nation children and youth from Quebec

BACKGROUND: Perfluoroalkyl substances (PFASs) are found in several consumer goods. Exposure to PFASs in children has been associated with alteration in thyroid hormones, which have critical roles in brain function. OBJECTIVE: In 2015, 198 children and youth (3-19 y) were recruited as part of the pilot project Jeunes, Environnement et Santé/Youth, Environment and Health (JES!-YEH!), realized in collaboration with four First Nation communities in Quebec. We aimed to evaluate serum concentrations of PFASs in relation to concentrations of thyroid-stimulating hormone (TSH), free thyroxine (T4) and thyroglobulin while adjusting for relevant confounders. METHODS: PFASs (PFOS, PFOA, PFHxS, PFNA), 2,2',4,4'-Tetrabromodiphenyl ether (PBDE-47) thyroid parameters (TSH, free T4, and thyroglobulin) were measured in serum samples of 186 participants. Iodine, creatinine, and cotinine were measured in urine samples. Serum levels of PFASs were compared to those measured in the general Canadian population and elsewhere. Multivariate regression analyses were performed to determine associations between PFASs and TSH, free T4 and thyroglobulin. RESULTS: PFOS, PFOA and PFHxS serum concentrations were low. However, PFNA concentrations among participants aged 12 to 19 years old from Anishinabe communities were three times higher than those measured in the Canadian Health Measures Survey (2009-2011) for the same age group (Geometric Means: 3.01 μg/L and 0.71 μg/L, respectively) and were particularly higher in the Anishinabe participants aged 6 to 11 years old (GM: 9.44 μg/L). Few participants had levels of TSH, free T4, and thyroglobulin outside age-specific paediatric ranges. When adjusted for relevant covariates and other contaminants, PFNA serum concentrations were positively associated with free T4 levels (Adjusted β = 0.36; p = 0.0014), but not with TSH and thyroglobulin levels. No association was observed between the other PFAS and thyroid hormones parameters. CONCLUSION: This pilot project reveals among the highest exposure to PFNA in children reported until today, and suggests effects of PFNA as an endocrine disruptor, highlighting the importance of investigating the sources and effects of disproportionate exposure to emerging contaminants in some indigenous communities and ban all PFAS at the international scale

Local country food sources of methylmercury, selenium and omega-3 fatty acids in Nunavik, Northern Quebec

Country foods are central to Inuit culture and replete in selenium (Se) and long-chain omega-3 polyunsaturated fatty acids (n-3 PUFA). However, some marine country foods bioaccumulate high concentrations of methylmercury (MeHg). Se and n-3 are associated with several health benefits in Nunavik, Northern Quebec, but, recent studies show that prenatal MeHg exposure is associated with visual, cognitive and behavioral deficit later in childhood. The study objectives are to identify contemporary country food sources of MeHg, Se and long-chain n-3 PUFA in Nunavik, particularly among childbearing-age women, taking into account regional differences in consumption profiles. The contribution of different country foods to daily MeHg, Se, long-chain n-3 PUFA intake (μg/kg body weight/day) was estimated using: (i) country food consumption and blood biomarkers data from the 2004 Nunavik Health Survey (387 women, 315 men), and (ii) data on MeHg, Se, long-chain n-3 PUFA concentrations found in Nunavik wildlife species. In the region where most traditional beluga hunting takes place in Nunavik, the prevalence of at-risk blood Hg (≥ 8 μg/L) in childbearing-age women was 78.4%. While most country foods presently consumed contain low MeHg, beluga meat, not a staple of the Inuit diet, is the most important contributor to MeHg: up to two-thirds of MeHg intake in the beluga-hunting region (0.66 of MeHg intake) and to about one-third in other regions. In contrast, seal liver and beluga mattaaq - beluga skin and blubber - only mildly contributed to MeHg (between 0.06 and 0.15 of MeHg intake), depending on the region. Beluga mattaaq also highly contributed to Se intake (0.30 of Se intake). Arctic char, beluga blubber and mattaaq, and seal blubber contributed to most long-chain n-3 PUFA intake. This study highlights the importance of considering interconnections between local ecosystems and dietary habits to develop recommendations and interventions promoting country foods' benefits, while minimizing the risk of MeHg from beluga meat, especially for childbearing-age women

Anemia, iron status, and associated protective and risk factors among children and adolescents aged 3 to 19 years old from four First Nations communities in Quebec

Objectives: Anemia and iron deficiency (ID) are frequent among Indigenous children of Canada, but few data are available in Quebec. The present study aimed to characterize anemia and ID prevalence and associated protective and risk factors among First Nations youth in Quebec. Methods: The 2015 First Nations (JES!-YEH!) pilot study was conducted among children and adolescents (3 to 19 years; n=198) from four First Nations communities in Quebec. Blood and urine samples and anthropometric measurements were collected. Hemoglobin (Hb), serum ferritin (SF), plasma hs-CRP, and urinary cotinine levels were measured. Factors associated with anemia and ID (including traditional and market food consumption) were assessed using an interview-administered food frequency questionnaire, based on which nutritional intakes were calculated. Structural equation models were used totest associations. Results: The prevalence of anemia and ID was elevated (16.8% and 20.5% respectively). Traditional meat, fruit, and fruit juice (naturaland powdered)—via their positive association with vitamin C intake—were the only food variables positively associated with SF (coefficient [95% CI] 0.017 [0.000, 0.114]; 0.090 [0.027, 0.161]; and 0.237 [0.060, 0.411]). Male sex was also associated with higher SF (0.295 [0.093, 0.502]). Inflammation status (hs-CRP > 5 mg/L) was inversely associated with Hb (−0.015 [−0.025,−0.005]), whereas SF was positively associated with Hb (0.066 [0.040, 0.096]). Fruit and juice consumption was also positively associated with Hb, via vitamin C intake and SF (0.004 [0.001, 0.010]; 0.008 [0.003, 0.017]). Conclusions: Interventions fostering healthier food environments as well as higher consumption of traditional meats and foods naturally rich in vitamin C, which is known to enhance iron absorption, and fighting inflammation could contribute to decrease the high prevalence of anemia and ID in this young Indigenous population.Objectifs : L’anémie et la carence en fer sont fréquentes chez les enfants autochtones au Canada, mais peu de données sont disponibles au Québec. La présente étude visait à caractériser la prévalence de l’anémie et de la carence en fer et les facteurs protecteurs et des risques associés chez des jeunes des Premières Nations du Québec. Méthodes : En 2015, l’étude pilote Jeunes Environnement et Santé (JES! - YEH!) a été menée chez des enfants et des adolescents (3 à 19 ans,n= 198) de quatre communautés de Premières Nations au Québec. Des échantillons de sang et d’urine et des mesures anthropométriques ont été recueillis. Les concentrations d’hémoglobine, de ferritine sérique, de hs-CRP plasmatique et decotinine urinaire ont été mesurées. Les facteurs associés à l’anémie et à la carence en fer (y compris la consommation d’aliments traditionnels et de marché) ont été évalués à l’aide de questionnaires de fréquences alimentaires administré par un assistant de recherche, à partir desquels les apports nutritionnels ont été calculés. Des modèles d’équations structurelles ont été utilisés pour tester les associations. Résultats : La prévalence de l’anémie et de la carence en fer était élevée (16,8 % et 20,5 % respectivement). La viande traditionnelle, les fruits et les jus de fruits (naturels et en poudre) − par l’intermédiaire de leur association positive avec l’apport en vitamine C − étaient les seules variables alimentaires positivement associées à la ferritine sérique (coefficient [IC à 95 %] : 0,017 [0,000, 0,114]; 0,090 [0,027, 0,161]; et 0,237 [0,060, 0,411]). Le sexe masculin était également associé à une ferritine sérique plus élevée (0,295 [0,093, 0,502]). Le statut inflammatoire (hs-CRP > 5 mg/L) était inversement associé à l’hémoglobine (−0,015 [−0,025,−0,005]) alors que la ferritine sérique était positivement associée à l’hémoglobine (0,066 [0,040, 0,096]). La consommation de fruits et de jus était aussi positivement associée à l’hémoglobine via l’apport en vitamine C et la ferritine sérique (0,004 [0,001, 0,010]; 0,008 [0,003, 0,017]). Conclusions : Les interventions favorisant des environnements alimentaires plus sains ainsi qu’une consommation plus élevée de viandes et d’aliments traditionnels naturellement riches en vitamine C, qui sont connus d’améliorer l’absorption de fer, ainsi que luttant contre l’inflammation pourraient contribuer à diminuer la prévalence élevée d’anémie et de la carence en fer dans cette jeune population autochtone

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

Trajectories of alcohol use and binge drinking among pregnant Inuit women

Background: This study investigated trajectories of alcohol use and binge drinking among Inuit women starting from a year before pregnancy until a year after delivery, examined transition rates between time periods, and established whether specific factors could be identified as predictors of changes in alcohol behaviors. Methods: Drinking trajectories and movement among alcohol users and binge drinkers (i.e., non-binging and binging) were explored by Markov modeling across time periods. Two hundred and forty-eight Inuit women from Arctic Quebec were interviewed at midpregnancy, and at 1 and 11 months postpartum to obtain descriptive data on alcohol use during the year before pregnancy, the conception period, the pregnancy and the year after delivery. Results: The proportions of drinkers and bingers were 73% and 54% during the year prior to pregnancy and 62% and 33% after delivery. Both alcohol use and binge drinking trajectories demonstrated a significant drop in prevalence between the year before conception to the conception period. We also noted high probabilities of becoming an abstainer or not binging at this time. However, up to 60% of women continued to drink alcohol during pregnancy. Women in couples and not consuming marijuana were more likely to decrease their binge drinking at conception. Conclusions: This study emphasizes the importance of including the period around conception in the definition of drinking patterns during pregnancy. The importance of considering alcohol consumption in a multidimensional way (personal, familial and social determinants) is also addressed while trying to minimize problems both for the fetus and the mother

Branched-Chain and Aromatic Amino Acids in Relation to Fat Mass and Fat-Free Mass Changes among Adolescents: A School-Based Intervention

Plasma levels of branched-chain amino acids (BCAA) and aromatic amino acids (AAA) are considered early metabolic markers of obesity and insulin resistance (IR). This study aimed to assess changes in plasma concentrations of BCAA/AAA and HOMA-IR2 (homeostasis model assessment of IR) after intervention-induced modifications in fat mass (FM) and fat-free mass (FFM) among French Polynesian adolescents. FM, FFM, plasma levels of BCAA and AAA, HOMA-IR2 were recorded at baseline and post intervention among 226 adolescents during a 5-month school-based intervention on diet and physical activity. Participants were divided into two subgroups according to their college attendance status which determined their intervention adherence: externs/half-residents (n = 157) and residents (n = 69). Four ordinal categories of body composition changes post-intervention were created for the analysis (FMgain/FFMlost < FMgain/FFMgain < FMlost/FFMlost < FMlost/FFMgain). After 5 months, changes in BCAA (p−trend < 0.001) and AAA (p−trend = 0.007) concentrations were positively associated with ordinal categories of body composition. HOMA-IR2 significantly decreased with FMlost (−0.40; 95% CI, −0.60 to −0.20) and increased with FMgain (0.23; 95% CI, 0.11 to 0.36). Our results suggest that FM loss is associated with a decrease in concentrations of obesity and IR metabolic markers which is more substantial when FM loss is accompanied with FFM gain