Impacts of toxic substances from oil production in the Alberta oil sands (AOS), such as polycyclic aromatic hydrocarbons (PAHs), have been widely debated. Studies have been largely restricted to exposures from surface mining in aquatic species. We measured PAHs in Woodland caribou (Rangifer tarandus caribou), moose (Alces americanus), and Grey wolf (Canis lupus) across three areas that varied in magnitude of in situ oil production. Our results suggest a distinction of PAH level and source profile (petro/pyrogenic) between study areas and species. Caribou samples indicated pyrogenic sourced PAHs in the study area previously devastated by forest fire. Moose and wolf samples from the high oil production area demonstrated PAH ratios indicative of a petrogenic source and increased PAHs, respectively. These findings emphasize the importance of broadening monitoring and research programs in the AOS.

•We measured PAHs from areas with varying degrees of in situ oil production activity.•PAH levels were measured in scat samples from three terrestrial species.•Caribou indicated pyrogenic PAHs in the area previously devastated by forest fire.•High oil production area moose and wolf showed petrogenic PAH characteristics.•Further scientific investigation of PAH exposures in these areas is warranted.

We demonstrate a distinction of PAH level and source profile in scat samples of three large mammals collected from areas with varying degrees of in situ oil production.