Mercury exposure in northern communities linked to eating waterfowl

(Press-News.org) A new study led by researchers at the University of Waterloo found that members of many Indigenous communities who eat certain types of locally harvested waterfowl, especially ducks with mixed or fish-based diets, may have higher levels of both mercury and healthy omega-3 fatty acids in their blood. 

The research, conducted in partnership with northern First Nations communities, suggests that waterfowl, such as ducks and geese, may need to be included more regularly in monitoring programs that track both contaminants and nutrients in traditional foods. 

“Traditional foods remain incredibly important to northern Indigenous communities, not only for nutrition but for cultural identity, community connection and food security,” said Dr. Brian Laird, a professor in Waterloo’s School of Public Health Sciences and the study’s lead author. “Our findings support efforts to promote traditional food consumption while also identifying ways to reduce risks from contaminants that enter Arctic ecosystems.” 

The researchers measured levels of healthy nutrients and mercury in blood and hair samples from community members in the Dehcho and Sahtú regions of the Northwest Territories, located in the Mackenzie River Valley, as well as in the community of Old Crow in the Yukon. Participants also completed dietary surveys about the traditional foods they had eaten over the past year. Using mathematical models, the research team examined whether reported consumption of certain foods was related to the mercury levels measured in people.  

“As expected, we found that eating certain fish, a well-known source of both omega-3 fatty acids and mercury, was associated with higher levels of both,” said Sara Packull-McCormick, a PhD candidate in Waterloo’s School of Public Health Sciences who led the data analysis for the study. “Somewhat unexpectedly, people who reported eating waterfowl also tended to have higher levels of omega-3 fatty acids and mercury levels, suggesting that waterfowl may contribute important nutrients alongside small amounts of mercury. 

“These findings highlight why it’s so important to look at the full picture, as while some traditional foods can contribute small amounts of mercury, they also provide essential nutrients that support health.” 
 
This collaborative research reflects Waterloo’s commitment to tackling humanity’s most complex challenges by bringing together researchers, community partners and diverse ideas through its Global Futures Networks. By connecting expertise across disciplines and regions, the university helps generate evidence that can directly support healthier, more sustainable futures for communities in Canada and around the world. 

The researchers hope this work will provide northern Indigenous communities with valuable support as they continue to protect health while sustaining traditional food practices that remain vital to culture, identity and overall well-being. 

The study, Determinants of human hair mercury, blood mercury, blood selenium and plasma omega-3 fatty acid levels within northern Canada, was recently published in the International Journal of Hygiene and Environmental Health. 

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