Bioaccumulation of polycyclic aromatic hydrocarbons by Arctic and temperate benthic species

Increasing oil and gas activities may substantially increase chemical stress to benthic ecosystems in the Arctic, pointing to the necessity to evaluate their environmemtal risks in these systems. Risk assessment procedures for oil related compounds (e.g., polycyclic aromatic hydrocarbons, PAHs) should address differences in exposure between Arctic and temperate benthos. Here we compare for the first time, the bioaccumulation of PAHs by Arctic benthic invertebrate species, with that of temperate species, based on their biota-sediment accumulation factors (BSAFs). Measured PAH BSAFs were generally higher in temperate bivalves (Limecola balthica) than in Arctic bivalves (Macoma calcarea), whereas BSAFs in Arctic polychaetes (Nephtys ciliata) showed higher values than in temperate polychaetes (Alitta virens). Differences in measured BSAFs were explained by the species-specific feeding modes and traits. However, modeled BSAFs revealed that steady state was not likely to be reached in the 28-d tests for all PAHs and organisms. Due to low numbers of individuals, most species-specific parameters carried too much uncertainty to reveal differences between Arctic and temperate species. The results of the present study suggest that data from temperate species could be used as a surrogate for Arctic species in risk assessment