Although the Arctic is often seen as clean and untouched, it acts as a sink for pollution from the rest of the world. Pollutants released in industrial regions are transported north by wind and ocean currents and slowly accumulate in Arctic ecosystems. In this project, we studied toxic metals and per- and polyfluoroalkyl substances known as PFAS in Svalbard reindeer to assess whether the consumption of Svalbard reindeer is safe and whether Svalbard reindeer are likely to experience harmful effects from their exposure to pollutants.
By analysing liver and meat samples from Svalbard reindeer harvested in late summer and autumn, we found clear seasonal differences in pollution levels. Reindeer shot later in the hunting season generally had
higher concentrations of both toxic metals and PFAS. This is likely because the reindeer sampled in October had been foraging for two extra months compared to those sampled in August, giving them more time to accumulate pollutants. In addition, the reindeer have seasonal shifts in diet, driven by changes in plant availability, which also can influence their exposure to different pollutants. For hunters, this means that
reindeer harvested early in the hunting season likely will contain lower levels of pollutants. However, since hunting on Svalbard is limited to only one animal per person, there is no indication that eating Svalbard
reindeer poses a health risk.
We also found that PFAS levels in Svalbard reindeer appear to be higher now than they were about ten years ago, and that the types of PFAS we detect in the reindeer have changed. This may reflect long-range
pollution or the release of stored pollutants from glaciers and permafrost as the Arctic warms. These findings highlight the importance of continued monitoring of PFAS in Svalbard reindeer, ideally in
collaboration with local hunters, to understand whether levels will continue to rise and what is driving this change.
In addition to measuring pollutants, we investigated whether these toxic metals or PFAS may affect the reindeer themselves. Even though concentrations were generally low, we found signs of changes on a
molecular level, especially in genes linked to lipid metabolism. This is important because Svalbard reindeer rely heavily on their seasonal fat storage to survive the long winter. While these effects are subtle and not visible in the animals, they suggest that long-term exposure to low levels of mixed pollutants may still influence the reindeer on a low biological level.
Overall, our project shows that pollution levels vary with season, that PFAS appear to be increasing over time, and that even low pollution levels may affect reindeer on a biological level. Together, this underlines
the need for continued monitoring in a rapidly changing Arctic, to both protect wildlife and humans.