Personne :
Ayotte, Pierre

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Ayotte
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Pierre
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Université Laval. Département de médecine sociale et préventive $2 lacnaf
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Voici les éléments 1 - 10 sur 24
  • Publication
    Accès libre
    Prenatal and early-life polychlorinated biphenyl (PCB) levels and behavior in Inuit preschoolers
    (Pergamon, 2015-03-18) Verner, Marc-André; Ayotte, Pierre; Plusquellec, Pierrich; Muckle, Gina; Desjardins, Justine; Dewailly, Éric; Cartier, Chloé
    Background: Whereas it is well established that prenatal exposure to polychlorinated biphenyls (PCBs) can disrupt children's behavior, early postnatal exposure has received relatively little attention in environmental epidemiology. Objectives: To evaluate prenatal and postnatal exposures to PCB-153, a proxy of total PCB exposure, and their relation to inattention and activity in 5-year-old Inuits from the Cord Blood Monitoring Program. Methods: Prenatal exposure to PCBs was informed by cord plasma PCB-153 levels. We used a validated pharmacokinetic model to estimate monthly infants' levels across the first year of life. Inattention and activity were assessed by coding of video recordings of children undergoing fine motor testing. We used multivariable linear regression to evaluate the association between prenatal and postnatal PCB-153 levels and inattention (n=97) and activity (n=98) at 5years of age. Results: Cord plasma PCB-153 was not associated with inattention and activity. Each interquartile range (IQR) increase in estimated infant PCB-153 levels at 2months was associated with a 1.02% increase in the duration of inattention (95% CI: 0.04, 2.00). Statistical adjustment for the duration of breastfeeding slightly increased regression coefficients for postnatal level estimates, some of which became statistically significant for inattention (months: 2-4) and activity (months: 2-5). Conclusions: Our study adds to the growing evidence of postnatal windows of development during which children are more susceptible to neurotoxicants like PCBs.
  • Publication
    Accès libre
    Altered fine motor function at school age in inuit children exposed to PCBs, methylmercury, and lead
    (Pergamon, 2016-08-27) Boucher, Olivier; Ayotte, Pierre; Muckle, Gina; Dewailly, Éric; Jacobson, Sandra W.; Jacobson, Joseph L.
    Background : Motor deficits have frequently been reported in methylmercury (MeHg) poisoning in adults. However, whether exposure to neurotoxic contaminants from environmental sources early in life is associated with neuromotor impairments has received relatively little attention. This study examines the relation of developmental exposure to MeHg, polychlorinated biphenyls (PCBs), and lead to motor function in school-age Inuit children exposed through their traditional diet. Methods : In a prospective study in Nunavik, children (mean age = 11.3 years) were assessed on a battery of fine motor tasks, namely the Stanford-Binet Copying subtest (N = 262), the Santa Ana Form Board, and the Finger Tapping Test (N = 215). The relation of mercury (Hg; as an index of MeHg exposure), PCB congener 153 (PCB153), and lead concentrations in cord and current blood samples to task performance was examined using linear regression analyses. Results : After adjustment for potential confounders and control for the other contaminants, higher current PCB concentrations were associated with poorer Santa Ana Form Board and Finger Tapping performance. Results were virtually identical when PCB153 was replaced by other PCB congeners. Higher current Hg levels were independently associated with poorer Finger Tapping performance. Conclusions : This is the first prospective longitudinal study in children to provide evidence of neuromotor impairments associated with postnatal exposure to seafood contaminants from environmental sources. Fine motor speed appears particularly sensitive to the effects of postnatal PCB exposure, which is unusually high in this population. Results with postnatal MeHg are concordant with previous cross-sectional studies with children and adults.
  • Publication
    Accès libre
    Assessing new dimensions of attentional functions in children prenatally exposed to environmental contaminants using an adapted Posner paradigm
    (Elsevier, 2015-07-30) Éthier, Audrey-Anne; Ayotte, Pierre; Muckle, Gina; Jacobson, Sandra W.; Jacobson, Joseph L.; Saint-Amour, Dave
    Chronic exposure to methylmercury (MeHg), lead (Pb) and polychlorinated biphenyls (PCBs) has been associated with a range of attention deficits in children, but it is not known whether selective spatial attention is also altered. We modified the classic Posner paradigm, which assesses visuospatial attention, to also assess vigilance and impulsivity. This paradigm is based on the well-documented findings that a target will be detected more quickly if a visual cue indicates beforehand where it will appear, and more slowly if the cue indicates a false spatial location. In our task, visual distractors were introduced, in addition to the classic Posner trials, to assess impulsivity, and a central smiley face, whose eye-movement cued the location of the targets, to measure spatial attention. This task was administered to 27 school-age Inuit children (mean age = 11.2 years) from Nunavik (Arctic Quebec, Canada), in which pre- and postnatal exposures to environmental contaminants had been documented from birth. After controlling for the impact of confounding variables, multivariable regressions revealed that prenatal exposures to PCBs and Pb were significantly associated with greater inattention and impulsivity, respectively, while current exposure to Pb was significantly associated with longer reaction times. Although a significant correlation was observed between cord blood PCB concentration and decreased visuospatial performance, no significant association was found after adjustment for confounders. No effect was found for Hg exposures. These results suggest that our adapted Posner paradigm is sensitive in detecting a range of attention deficits in children exposed to environmental contaminants; implications for future studies are discussed.
  • Publication
    Accès libre
    Overweight and obesity prevalence among school-aged Nunavik Inuit children according to three BMI classification systems
    (Elsevier Science Pub. Co., 2015-06-18) Roy, Cynthia; Lucas, Michel; Medehouenou, Thierry Comlan Marc; St-Jean, Audray; Meziou, Salma; Ayotte, Pierre; Muckle, Gina
    Purpose Little is known about the suitability of three commonly used body mass index (BMI) classification system for Indigenous children. This study aims to estimate overweight and obesity prevalence among school-aged Nunavik Inuit children according to International Obesity Task Force (IOTF), Centers for Disease Control and Prevention (CDC), and World Health Organization (WHO) BMI classification systems, to measure agreement between those classification systems, and to investigate whether BMI status as defined by these classification systems is associated with levels of metabolic and inflammatory biomarkers. Methods Data were collected on 290 school-aged children (aged 8–14 years; 50.7% girls) from the Nunavik Child Development Study with data collected in 2005–2010. Anthropometric parameters were measured and blood sampled. Participants were classified as normal weight, overweight, and obese according to BMI classification systems. Weighted kappa (¿w) statistics assessed agreement between different BMI classification systems, and multivariate analysis of variance ascertained their relationship with metabolic and inflammatory biomarkers. Results The combined prevalence rate of overweight/obesity was 26.9% (with 6.6% obesity) with IOTF, 24.1% (11.0%) with CDC, and 40.4% (12.8%) with WHO classification systems. Agreement was the highest between IOTF and CDC (¿w = .87) classifications, and substantial for IOTF and WHO (¿w = .69) and for CDC and WHO (¿w = .73). Insulin and high-sensitivity C-reactive protein plasma levels were significantly higher from normal weight to obesity, regardless of classification system. Among obese subjects, higher insulin level was observed with IOTF. Conclusions Compared with other systems, IOTF classification appears to be more specific to identify overweight and obesity in Inuit children.
  • Publication
    Accès libre
    Food insecurity and nutritional biomarkers in relation to stature in Inuit children from Nunavik
    (Canadian Public Health Association, 2014-07-22) Dallaire, Renée; Lucas, Michel; Ayotte, Pierre; Muckle, Gina; Jacobson, Joseph L.; Dewailly, Éric; Jacobson, Sandra W.; Pirkle, Catherine
    OBJECTIVES: Inuit in Canada experience alarming levels of food insecurity, but nutritional and physiological consequences are poorly documented, especially in school-age children. The objective of this study was to assess the relation of food insecurity to iron deficiency and stature in school-aged Inuit children from Nunavik (Northern Quebec). METHODS: Food insecurity, iron deficiency, and stature were assessed in a cohort of children. Food insecurity was determined by interviewing the children’s mothers. Multiple logistic regression was used to evaluate the association of food insecurity to iron deficiency and short stature. We defined short stature as a height in the lowest tertile for age and sex, based on Canadian growth charts. The relation of food insecurity to height (cm) was analyzed with a general linear model. Statistical models controlled for age, sex, normal/overweight/obese status, prenatal lead exposure and postnatal polychlorinated biphenyls exposure. RESULTS: Half of the children (49.7%, n=145) were food insecure, while one third were iron depleted, 12.6% had anaemia, and 8.7% had irondeficiency anaemia. The multivariate odds ratio of anaemia was 1.82 (95% CI: 0.97, 3.42, p=0.06) for food-insecure children. Prevalence of short stature was 18.7%. Food-insecure children were an average of 2 cm shorter (95% CI: -0.48, -3.17) than food-secure children (p<0.01). CONCLUSION: In this population, food-insecure children have greater burdens of nutritional deficiencies and slower linear growth. Considering the high prevalence of food insecurity among Inuit children in Nunavik, nutritional deficiencies and adverse effects on development should be carefully monitored.
  • Publication
    Accès libre
    MercuNorth - monitoring mercury in pregnant women from the Arctic as a baseline to assess the effectivness of the Minamata Convention
    (Oulu : International Association of Circumpolar Health Publishers, 2021-06-03) Adlard, Bryan; Lemire, Mélanie; Bonefeld-Jørgensen, Eva C.; Long, Manhai; Ólafsdóttir, Kristín; Odland, Jon Øyvind; Rautio, Arja; Myllynen, Päivi; Sandanger, Torkjel M.; Dudarev, Alexey A.; Bergdahl, Ingvar A.; Berner, Jim; Ayotte, Pierre
    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.
  • Publication
    Accès libre
    Prenatal exposure to polybrominated diphenyl ethers and predisposition to frustration at 7 months : results from the MIREC Study
    (Pergamon, 2018-06-22) Tremblay, Émilie; Boivin, Michel; Arbuckle, Tye Elaine; Ouellet, Emmanuel.; Fraser, William Donald; Forget-Dubois, Nadine; Lemelin, Jean-Pascal; Séguin, Jean R.; Oulhote, Youssef; Ayotte, Pierre; Muckle, Gina; Dionne, Ginette; Lanphear, Bruce P.
    Background: Prenatal exposure to polybrominated diphenyl ethers (PBDEs) has been associated with cognitivedeficits and behavioral problems in children. To date, no study has examined this exposure in association withneurobehavioral development in infants younger than 12 months assessed with observational tasks. Objectives: This study examined the relation between prenatal PBDE concentrations and predisposition tofrustration, assessed by the arm restraint task (ART), in Canadian infants. Methods: In a prospective longitudinal study conducted in Canada, exposure to nine PBDE congeners wasmeasured in maternal plasma during the first trimester of pregnancy. The ART was used to measure predis-position to frustration in infancy (N = 333; mean age = 6.9 months), as assessed by negative vocalizations(crying and screaming) and physical reactivity (discomfort movements). Results: Maternal plasma PBDE-47 concentrations collected during pregnancy were associated with negativevocalizations using the ART (adjusted Relative Risk [aRR] = 1.04, 95% CI: 1.00, 1.09). Prenatal PBDE-99concentrations during pregnancy were also related to a shift to the left in the tail of the distribution of onset ofnegative vocalizations as measured by a decrease of 38 s (95% CI: −78.1, 1.3) in the 75th quantile of thedistribution for infants whose mothers had detectable levels of PBDE-99 compared to infants of mothers withundetectable levels. Similarly, infants whose mothers had detectable levels of PBDE-100 showed an increase of24.1 s (95% CI: 4.1, 44.1) in the 75th quantile of the distribution of proportion of time in negative vocalizationscompared with infants of mothers with undetectable levels. Finally, the association between PBDE-47 and PBDE-153, and physical reactivity was significantly modified by sex (p < 0.1), with opposite patterns in girls andboys. Conclusions: Prenatal exposure to PBDEs was associated with increased incidence of crying and screaming withdelayed onset of discomfort movement, which may indicate a predisposition to frustration and lack of habi-tuation in infants younger than 12 months from the general population.
  • Publication
    Accès libre
    Perfluoroalkyl acid and bisphenol-A exposure via food sources in four First Nation communities in Quebec, Canada
    (London : CAB International, 2022-03-11) Dubeau, Claudelle; Aker, Amira; Caron-Beaudoin, Élyse; Ayotte, Pierre; Blanchette, Caty; Gros-Louis McHugh, Nancy; Lemire, Mélanie
    Objective: To document perfluoroalkyl acids (PFAA) and bisphenol-A (BPA) exposure in four First Nation communities in northern Quebec compared with the Canadian Health Measures Survey (CHMS Cycle 5 2016–2017) and examine the associations between dietary consumption and chemical exposure. Design: We used cross-sectional data from the JES-YEH! project conducted in collaboration with four First Nation communities in 2015. A FFQ collected information on diet, and PFAA and BPA were measured in biological samples. We used generalised linear models to test the associations between food intake and chemical biomarkers. Setting: Northern Quebec. Participants: Youth aged 3–19 years (n 198). Results: Mean perfluorononanoic acid (PFNA) levels were significantly higher in JES-YEH! than CHMS, and BPA levels were higher among those aged 12–19 years compared with CHMS. Dairy products were associated with PFNA among Anishinabe and Innu participants (geometric mean ratio 95 % CI: 1·53 (95 % CI 1·03, 2·29) and 1·52 (95 % CI 1·05, 2·20), respectively). PFNA was also associated with ultra-processed foods (1·57 (95 % CI 1·07, 2·31)) among Anishinabe, and with wild fish and berries (1·44 (95 % CI 1·07, 1·94); 1·75 (95 % CI 1·30, 2·36)) among Innu. BPA was associated with cheese (1·72 (95 % CI 1·19, 2·50)) and milk (1·53 (95 % CI 1·02, 2·29)) among Anishinabe, and with desserts (1·71 (95 % CI 1·07, 2·74)), processed meats (1·55 (95 % CI 1·00, 2·38)), wild fish (1·64 (95 % CI 1·07, 2·49)) and wild berries (2·06 (95 % CI 1·37, 3·10)) among Innu. Conclusions: These results highlight the importance of better documenting food-processing and packaging methods, particularly for dairy products, and their contribution to endocrine disruptors exposures as well as to promote minimally processed and unpackaged foods to provide healthier food environments for youth in Indigenous communities and beyond.
  • Publication
    Accès libre
    Non-persistent exposures from plasticizers or plastic constituents in remote Arctic communities : a case for further research
    (New York NY: Nature Pub. Group, 2022-03-28) Aker, Amira; Caron-Beaudoin, Élyse; Ayotte, Pierre; Ricard, Sylvie; Gilbert, Véronique; Avard, Ellen; Lemire, Mélanie
    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.
  • Publication
    Accès libre
    Seasonal variations in exposure to methylmercury and its dietary sources among pregnant Inuit women in Nunavik, Canada
    (Elsevier, 2020-11-01) De Moraes Pontual, Mariana; Ayotte, Pierre; Little, Matthew; Furgal, Chris; Boyd, Amanda D.; Muckle, Gina; Avard, Ellen; Ricard, Sylvie; Gauthier, Marie-Josée; Anassour-Laouan Sidi, Elhadji; Lemire, Mélanie
    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.