Jeunes, Environnement Et Santé / Youth, Environment and Health (JES!-YEH!) Pilot Project in Four First Nation Communities in Quebec: Exposure to Perfluorononanoic Acid (PFNA) and Associations with Thyroid Hormones

Abstract

Background/Aim. Perfluorononanoic acid (PFNA) and other perfluorinated compounds have various industrial uses, and possible sources of exposure include food packaging, consumer products, house dust and/or drinking water. Exposure to PFNA in children has been associated with alteration in thyroid hormones, which have critical roles in metabolism regulation and during brain development. In 2015, the pilot project Jeunes, Environnement et Santé / Youth, Environment and Health (JES!-YEH!) was conducted among children and youth (3-19y) in collaboration with four First Nation communities in Quebec (n=198). The present study aims at evaluating the associations between various perfluorinated compounds exposure and thyroid hormones levels, while adjusting for relevant co-variables. Methods and results. During this study, perfluorinated compounds, thyroid hormones (e.g TSH and free T4) iodine and creatinine were measured in blood and urine samples. Main findings showed low exposure to major perfluorinated compounds, excepted for PFNA (GM: 2.09 μg/L). Compared to the Canadian Health Measure Survey (GM: 0.71 μg/L), PNFA levels were significantly higher among Anishinabe participants (GM: 5.12 μg/L), and particularly among those aged 6 to 11 years old (GM: 9.44 μg/L). Despite multiples efforts with community partners, no local source was identified. Few participants had abnormal TSH and free T4 levels. Conversely, preliminary analyses show positive associations between PFNA and free T4 levels (Spearman’s r=0.23; p=0.0016). When adjusted for age, age-squared, BMI-z-score, urinary creatinine and nation, free T4 levels remain positively associated with PFNA levels (Adjusted β=0.39; p=0.0014; R2 = 0.24). Conclusion. Overall, this pilot project suggest potential effects of PFNA as an endocrine disruptor, and highlight the importance of better investigating the sources and effects of disproportionate exposure to emerging environmental contaminants in indigenous communities.