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

Abstract

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 legacy and novel PFASs in lipid-rich tissues such as blubber. Here we report the distribution of 24 PFASs, total fluorine, 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 of wet weight) and decreased in the following order: blood > kidney ≈ lung ≈ ovary > skin ≈ muscle ≈ blubber. Most of the EOF consisted 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 is unlikely to explain the high concentrations of EOF in blubber. While the identity of this unknown organofluorine and its pervasiveness in marine mammals require further investigation, this work suggests that exposure of killer whales to organofluorine substances may be underestimated by determination of legacy PFASs exclusively in liver or blood.

A Critical Review on Transplacental Transfer of Per- and Polyfluoroalkyl Substances: Prenatal Exposure Levels, Characteristics, and Mechanisms

“…Consequently, many fluorinated alternatives, which are regarded as the “environmentally friendly” substitutes, are incorporated into the production and use without any discussion. On the other hand, with the advancement of analytical technology, some new PFASs monomers have been detected in environmental media and organisms, − which has caused great concern. Therefore, solving the environmental issues that are linked to PFASs still has a long way to go.…”

Addressing Urgent Questions for PFAS in the 21st Century

“…Understudied groups of PFAS (e.g., neutral, cationic, zwitterionic, cyclic) may have substantially different biological behavior that could be missed by established sampling approaches. For example, if their tissue distributions vary from those of anionic PFAAs, focusing on only serum or liver concentrations could miss critical accumulation sites for these PFAS (e.g., in lipids). The structural diversity of PFAS and the fact that exposures are nearly always to mixtures rather than single substances complicates the search for mechanisms and structure–activity relationships.…”

Quantification of per‐ and polyfluoroalkyl substances with a modified total organic carbon analyzer and ion chromatography

“…CIC methods typically achieve lower detection limits by solid phase extraction (SPE) of samples prior to CIC measurements (e.g., EOF or AOF) Schultes et al, 2020;Spaan et al, 2020;von Abercron et al, 2019). Although these methods have been developed and validated separately, we conducted one experiment to demonstrate that CIC-F TOC is amenable to samples concentrated via EOF.…”