High Concentrations of Unidentified Extractable Organofluorine observed in Blubber from a Greenland Killer Whale (Orcinus orca)

It is generally accepted that per- and polyfluoroalkyl substances (PFASs) occur primarily in protein-rich tissues such as blood and liver, but few studies have examined the occurrence of PFASs (in particular emerging PFASs), in lipid-rich tissues such as blubber. Here we report the distribution of 24 PFASs, total fluorine (TF) and extractable organic fluorine (EOF) in eight different tissues of a killer whale (Orcinus orca) from East Greenland. The sum of target PFAS concentrations was highest in liver (352 ng/g ww) and decreased in the order blood > kidney ≈ lung ≈ ovary > skin ≈ muscle ≈ blubber. Most of the EOF was made up of known PFASs in all tissues except blubber, which displayed the highest concentration of EOF, almost none of which was attributed to targeted PFASs. Suspect screening using high-resolution mass spectrometry revealed the presence of additional PFASs but the magnitude of peak areas could not explain the high concentrations of EOF in blubber. While the identity of this unknown organofluorine and its pervasiveness in marine mammals requires further investigation, this work suggests that exposure of killer whales to organofluorine substances may be underestimated by determination of legacy PFASs exclusively in liver tissues.