This study was designed to address the concerns of the Chipewyan Prairie Dene First Nation community regarding fish quality in three water bodies (Winefred Lake, Kirby Lake and Hook Lake), which were potentially impacted by intensive large-scale oil sands developments.
Fish samples from Hook, Winefred and Kirby Lakes were collected and analyzed for polycyclic aromatic hydrocarbons (PAHs) and a suite of 31 metals, including mercury, arsenic, cadmium and lead. PAHs, in particular, can be associated with oil and gas activity. A food consumption survey was administered to gather information on community fish consumption patterns. The collected data were used to conduct a human health risk assessment (HHRA) and provide community-specific benchmark fish consumption rates for whitefish, northern pike/jackfish and walleye/pickerel.
The results showed that all of the fish samples had mercury levels below the Health Canada commercial sale guideline of 0.5 ppm. Jackfish from Hook Lake had higher levels of mercury than all other fish in the study, but these levels were still below the acceptable limit. There were no measurable levels of PAHs in any of the fish sampled.
The study concluded that fish were generally safe to eat in the quantities reported by community members. For lakes with mercury levels similar to those measured in jackfish and pickerel from Hook Lake, Alberta Health has issued consumption advisories for women of child-bearing age and children.