Assessment of beaver tissue quality in the traditional territory of the Chipewyan Prairie Déné First Nation

Beaver is an important traditional food for members of the Chipewyan Prairie Déné First Nation (CPDFN). This study was designed to address community concerns regarding beaver quality in waterways, rivers and wetlands within the traditional territory of the CPDFN given  potential contamination from large-scale oil sands development.

Beaver tissues (muscle, liver and kidney) were sampled and analyzed for a suite of 19 metals, including arsenic, cadmium, lead, and mercury. Metal concentrations in beaver samples were compared to those collected for the 2005 CPDFN Traditional Food Quality Study in order to establish temporal trends. A dietary survey was also completed by community participants. Together, these data were used to conduct a human health risk assessment to characterize potential risk of metals on human health.

The results of this study showed that all beaver samples contained low levels of heavy metals and were similar to  levels in meats available in Canadian supermarkets (e.g., chicken, beef, pork). However, cadmium and mercury concentrations in the beaver kidney and liver were much higher than in the muscle. Therefore, consumption of beaver organ meat should be limited and eaten in small quantities on an occasional basis. Lead was measured at higher concentrations in some of the beaver samples. This was attributed to the use of lead ammunition.

The study concluded that beaver meat continues to be a healthy food option and CPDFN members do not need to limit their consumption of beaver muscle. The consumption of organ meat from younger animals was recommended over the consumption of organs from older animals as cadmium concentrations naturally increase in animals with age. Non-lead ammunition should be used when harvesting beaver in order to reduce the risks of exposure to lead. The concentrations of heavy metals in beavers have not changed substantially over the last 15 years.