Traditional knowledge may limit mercury exposure in northern Indigenous communities

A study of more than 600 residents in the Dehcho and Sahtu regions and Old Crow, Yukon found that traditional foods such as lake trout, ducks and geese are linked to higher hair mercury measurements, but overall mercury exposure remained relatively low and within health guidelines.

A recent study examined how traditional knowledge and harvesting practices relate to contaminant exposure in northern Indigenous communities. Researchers collected data from over 600 residents in the Dehcho and Sahtu regions of the Northwest Territories and in Old Crow, Yukon, between 2016 and 2019. They measured mercury and omega-3 fatty acids in hair and blood and compared results to dietary and demographic information. The authors say traditional foods are important to local diets and stress monitoring contaminants while supporting those practices. Key findings: - The study sampled more than 600 people from the Dehcho and Sahtu regions and Old Crow between 2016 and 2019. - Researchers measured mercury and omega-3 fatty acids in hair and blood and compared levels with diet and demographic factors. - Foods such as lake trout, ducks and geese were associated with higher hair mercury, especially among people in the Sahtu region compared with the broader Canadian population. - Overall total mercury exposure among participants was reported as relatively low and within public health guidelines. - Researchers note mercury arrives from both natural sources (for example, wildfires) and human activities (including coal burning and gold mining abroad) and can travel long distances. - Seasonal, varied traditional diets and guidance from elders were identified as factors that can affect exposure patterns. Summary: The study reports that some traditional foods are linked to higher mercury measurements in hair but that total exposure in the sampled communities remains within health guidelines. Researchers say they are highlighting the importance of traditional foods while continuing to monitor contaminants and exploring ways to reduce their entry into the Arctic ecosystem. Communities are also relying on elders and local knowledge as climate change affects harvesting areas and water sources.