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