Developmental exposure to legacy environmental contaminants, medial temporal lobe volumes and spatial navigation memory in late adolescents.

Exposure to lead, mercury, and polychlorinated biphenyls (PCBs) has been causally linked to spatial memory deficits and hippocampal changes in animal models. The Inuit community in Northern Canada is exposed to higher concentrations of these contaminants compared to the general population. This study aimed to 1) investigate associations between prenatal and current contaminant exposures and medial temporal brain volumes in Inuit late adolescents; 2) examine the relationship between these brain structures and spatial memory; and 3) assess the mediating role of brain structures in the association between contaminant exposure and spatial memory.

Combined Exposure to Folate and Lead during Pregnancy and Autistic-Like Behaviors among Canadian Children from the MIREC Pregnancy and Birth Cohort.

Background: Folic acid (FA) supplementation may attenuate the associations between gestational exposure to certain chemicals and autism or autistic-like behaviors, but to our knowledge, this has not been assessed for lead.

Objectives: We examined whether the relationship between gestational blood-lead levels (BLLs) and autistic-like behaviors was modified by gestational plasma total folate concentrations, FA supplementation, and maternal methylenetetrahydrofolate reductase () 677C>T genotype.

Methods: We used data from the Maternal-Infant Research on Environmental Chemicals study (2008-2011), a Canadian pregnancy and birth cohort study.

Performance of the Social Responsiveness Scale-2 for the Assessment of Autistic Behaviors in a Sample of Canadian Preschool-Aged Children.

Behavioral traits of autism spectrum disorder (ASD) typically present in early childhood, underscoring the importance of screening tools for the early identification of ASD. The current study compared scores on the Social Responsiveness Scale-Second Edition (SRS-2) Preschool Form between the US standardization sample (n = 247) and a Canadian cohort of preschool-aged children (n = 595) recruited from the Maternal-Infant Research on Environmental Chemicals (MIREC) study. In the MIREC sample, we examined whether ASD-like traits are correlated with sociodemographic characteristics and child intellectual abilities, and how maternal ratings of social skills assessed by the SRS-2 are associated with maternal ratings of general problem behaviors.

Brain gray matter volume of reward-related structures in Inuit adolescents pre- and postnatally exposed to lead, mercury and polychlorinated biphenyls.

This study aimed to assess associations between prenatal and postnatal exposure to lead (Pb), mercury (Hg) and polychlorinated biphenyls (PCBs) and gray matter volume of key regions of the brain reward circuit, namely the caudate nucleus, putamen, nucleus accumbens (nAcc), the amygdala, the orbitofrontal cortex (OFC) and the anterior cingulate cortex (ACC). Structural magnetic resonance imaging (MRI) was conducted in 77 Inuit adolescents (mean age = 18.39) from Nunavik, Canada, who also completed the Brief Sensation Seeking Scale (BSSS-4) and Sensation Seeking - 2 (SS-2), two self-report questionnaires evaluating the tendency toward sensation seeking, which is a proxy of reward-related behaviors.

Stress and anxiety during pregnancy and length of gestation: a federated study using data from five Canadian and European birth cohorts.

While its etiology is not fully elucidated, preterm birth represents a major public health concern as it is the leading cause of child mortality and morbidity. Stress is one of the most common perinatal conditions and may increase the risk of preterm birth. In this paper we aimed to investigate the association of maternal perceived stress and anxiety with length of gestation.

Using latent class analysis to operationalize a wholistic assessment of Inuit health and well-being.

Many indigenous cultures conceptualize health wholistically, whereby physical, mental, spiritual and relational dimensions of health are interconnected. Yet, quantitative approaches to studying Indigenous health remain anchored in western perspectives, that separate the dimensions of health. This paper aims to operationalize a wholistic indicator of health based on the IQI model of Inuit health.

The Qanuilirpitaa? 2017 Nunavik Health Survey: design, methods, and lessons learned.

Objective: To depict the design, methods, sociodemographic characteristics of the population, and lessons learned during the Qanuilirpitaa? 2017 Nunavik Inuit Health Survey, the third major health survey to be conducted among youth and adults residing in Nunavik (Northern Quebec, Canada).

Methods: Qanuilirpitaa? 2017 is a cross-sectional survey that served to update information regarding various aspects of physical health, mental health, and general well-being of Nunavimmiut. The survey was guided by the ethics principles of Ownership, Control, Access, and Possession (OCAP®) ( https://fnigc.

Prenatal fluoride exposure, offspring visual acuity and autonomic nervous system function in 6-month-old infants.

Background: Prenatal fluoride exposure can have adverse effects on children's development; however, associations with visual and cardiac autonomic nervous system functioning are unknown. We examined associations between prenatal fluoride exposure and visual acuity and heart rate variability (HRV) in 6-month-old infants.

Methods: We used data from Canadian mother-infant pairs participating in the Maternal-Infant Research on Environmental Chemicals (MIREC) cohort.

Antidepressants use during pregnancy and child psychomotor, cognitive and language development at 2 years of age-Results from the 3D Cohort Study.

Approximately 5.5% of pregnant women take antidepressants. Studies on prenatal exposure to antidepressants reported no association with child cognition, and inconsistent results with motor function and language development.

Impact of COVID-19 and Vaccination During Pregnancy on Placenta-Mediated Complications (COVIGRO Study).

Objectives: COVID-19 has been associated with preterm birth (PTB) and placental-mediated complications, including fetal growth restriction and preeclampsia (PE). This study aimed to estimate the impact of COVID-19 and vaccination on adverse pregnancy outcomes and markers of placental function.

Methods: We performed a study on a prospective cohort of women recruited in the first trimester of pregnancy during the early COVID-19 pandemic period (December 2020 to December 2021).

Cohort profile update: The Canadian Maternal-Infant Research on Environmental Chemicals Child Development study (MIREC-CD PLUS).

Background: The pan-Canadian Maternal-Infant Research on Environmental Chemicals (MIREC) study was established to determine whether maternal environmental chemical exposures were associated with adverse pregnancy outcomes in 2001 pregnant women.

Objectives: The MIREC-Child Development (CD PLUS) study followed this cohort with the goal of assessing the potential effects of prenatal exposures on anthropometry and neurodevelopment in early childhood.

Population: MIREC families with children between the ages of 15 months and 5 years who had agreed to be contacted for future research (n = 1459) were invited to participate in MIREC-CD PLUS which combines data collected from an online Maternal Self-Administered Questionnaire with biomonitoring and neurodevelopment data collected from two in-person visits.

Pre- and postnatal exposure to legacy environmental contaminants and sensation seeking in Inuit adolescents from Nunavik.

Despite extensive evidence from cohort studies linking exposure to lead (Pb), mercury (Hg) and polychlorinated biphenyls (PCBs) to numerous cognitive outcomes in children and adolescents, very few studies addressed reward sensitivity, a key dimension of emotional regulation. The present study aimed to examine associations between pre- and postnatal exposure to these environmental neurotoxicants and sensation seeking, a behavioral feature of reward. A total of 207 Inuit adolescents (mean age = 18.

Early-Life Exposure to a Mixture of Phenols and Phthalates in Relation to Child Social Behavior: Applying an Evidence-Based Prioritization to a Cohort with Improved Exposure Assessment.

Background: Previous studies aiming at relating exposure to phenols and phthalates with child social behavior characterized exposure using one or a few spot urine samples, resulting in substantial exposure misclassification. Moreover, early infancy exposure was rarely studied.

Objectives: We aimed to examine the associations of phthalates and phenols with child social behavior in a cohort with improved exposure assessment and to identify the chemicals supported by a higher weight of evidence.

Smoking cessation attempts and successes among Nunavimmiut.

Objectives: The smoking rate in Canada has declined in past decades, yet smoking rates remain high in Nunavik (northern Québec), where an estimated 80% of adult respondents smoke. We investigated sociodemographic factors, smoking behaviours, harm perception, and social support as determinants of smoking cessation attempts and successes among Nunavimmiut.

Methods: Past year smoking frequency, quantity smoked, and cessation attempts and aids were documented in a sample of 1326 Nunavimmiut aged 16 and over in the Qanuilirpitaa? 2017 survey.

Prenatal and concurrent blood mercury concentrations and associations with IQ in canadian preschool children.

Background: Prenatal and childhood mercury (Hg) exposures have been associated with negative impacts on child neurodevelopment. It is unclear if associations persist at the low Hg exposures typical in Western countries.

Objective: To examine associations between prenatal/childhood blood Hg concentrations and child IQ in Canadian male and female children while considering the potential modifying role of prenatal fish consumption.

Profiles of childhood adversities in Inuit from Nunavik: description and associations with indicators of socioeconomic characteristics, support, and community involvement.

Objectives: Distress and associated health problems reported by Nunavik Inuit emanate from heterogeneous roots, including adverse childhood experiences. This study aims to (1) identify distinct childhood adversity profiles and (2) examine associations between these profiles and sex, socioeconomic characteristics, social support, and community involvement among Nunavimmiut.

Methods: In a sample of 1109 adult Nunavimmiut, sex, socioeconomic characteristics, support, community involvement, residential school attendance, and 10 forms of adverse childhood experiences (ACEs) were documented using questionnaires.

Prenatal and childhood chlordecone exposure, cognitive abilities and problem behaviors in 7-year-old children: the TIMOUN mother-child cohort in Guadeloupe.

Background: Chlordecone is a highly persistent organochlorine insecticide that was intensively used in banana fields in the French West Indies, resulting in a widespread contamination. Neurotoxicity of acute exposures in adults is well recognized, and empirical data suggests that prenatal exposure affects visual and fine motor developments during infancy and childhood, with greater susceptibility in boys.

Objective: To assess the associations between pre- and postnatal exposures to chlordecone and cognitive and behavioral functions in school-aged children from Guadeloupe.

Sociocultural determinants of alcohol and cannabis use and misuse among Nunavimmiut.

Objective: Stemming from historical traumas and changes in the Inuit way of life, substance use and its intertwined problems are a major cause of concern for Nunavimmiut. This study's objective is to investigate sociocultural determinants of substance use and misuse to inform culturally appropriate public health programs.

Methods: The 2017 Qanuilirpitaa? survey was conducted among a sample intended to be representative of Nunavimmiut aged 16 and over (total n = 1326).