Examining Relationships between Pb and Nutrient Intake and Sources of Pb in the Sahtú, NWT

• Main Author: Lazarescu, Calin
• Format: Master Thesis
• Language: English
• Published: University of Waterloo 2022
• Subjects: Northwest Territories; Canada; Dehcho Region; Subarctic
• Online Access: http://hdl.handle.net/10012/18621

Background: The Sahtú is a subarctic region located in the Northwest Territories, Canada. It is comprised of five remote communities, with a total population of approximately 2600 people. Over 75% of the total population is Indigenous, with the largest group being Dene First Nation. Previous human biomonitoring work in the region had indicated lead (Pb) levels in both blood and urine were higher when compared to both the neighbouring Dehcho region, and the general Canadian population. Pb is an element that is toxic to humans in high concentrations. Pb is commonly absorbed through inhalation, ingestion, and dermal exposure, and is distributed in bone and blood. Negative health implications related to chronic exposure include neurological, cardiovascular, and renal impacts. Pb is still widespread in environmental media including soil, air, and water, from anthropogenic releases into the environment, as well as use in industry and hobbies. Specific to the Northern Canada, diet, and hunting practices, such as the use of Pb ammunition, are key routes of exposure. Methods: Using data collected from the biomonitoring project, and supplemental analysis on biobanked blood samples, statistical analysis to determine the correlations and associations between nutrient biomarkers and Pb was conducted. Nonparametric and parametric correlations were conducted between age, BMI, sex, smoking status, alcohol consumption status, zinc, iron, vitamin D with Pb, followed by multivariate linear regression. Nutritional levels of zinc, iron, and vitamin D were assessed and compared to national averages and deficiency thresholds. An exposure survey adapted for northern Canadian Indigenous populations was developed through supplementing and adapting questions collated from existing tools and information from a literature review. The survey was piloted, and feedback was gathered from community members after interviews with research team members. The survey was finalized and ready for future implementation. Results: 128 biobanked blood ...