Abstract
We compared long-term (1977 to 2014) trends in concentrations of PFAS in eggs of the marine sentinel species, the Northern gannet (Morus bassanus), from the Irish Sea (Ailsa Craig) and the North Sea (Bass Rock). Concentrations of eight perfluorinated carboxylic acids (PFCAs) and three perfluorinated sulfonates (PFSAs) were determined and we report the first dataset on PFAS in UK seabirds before and after the PFOS ban. There were no significant differences in ∑PFAS or ∑PFSAs between both colonies. The ∑PFSAs dominated the PFAS profile (>80%); PFOS accounted for the majority of the PFSAs (98–99%). In contrast, ∑PFCAs concentrations were slightly but significantly higher in eggs from Ailsa Craig than in those from Bass Rock. The most abundant PFCAs were perfluorotridecanoate (PFTriDA) and perfluoroundecanoate (PFUnA) which, together with PFOA, comprised around 90% of the ∑PFCAs.The ∑PFSAs and ∑PFCAs had very different temporal trends. ∑PFSAs concentrations in eggs from both colonies increased significantly in the earlier part of the study but later declined significantly, demonstrating the effectiveness of the phasing out of PFOS production in the 2000s. In contrast, ∑PFCAs concentrations in eggs were constant and low in the 1970s and 1980s, suggesting minimal environmental contamination, but residues subsequently increased significantly in both colonies until the end of the study. This increase appeared driven by rises in long chain compounds, namely the odd chain numbered PFTriDA and PFUnA. PFOA, had a very different temporal trend from the other dominant acids, with an earlier rise in concentrations followed by a decline in the last 15 years in Ailsa Craig; later temporal trends in Bass Rock eggs were unclear.Although eggs from both colonies contained relatively low concentrations of PFAS, the majority had PFOS residues that exceeded a suggested Predicted No Effect Concentration and ~ 10% of the eggs exceeded a suggested Lowest-Observable-Adverse-Effect.
Highlights
Perfluoroalkyl substances (PFAS) are man-made compounds, produced since the 1950s and, historically considered unreactive
Our objectives were to: 1) determine how the concentrations of PFAS in gannet eggs in the two colonies changed over a period of 37 years; 2) investigate how temporal trends varied between individual Perfluorinated sulfonates (PFSAs) and Perfluorinated carboxylic acids (PFCAs), and 3) examine spatial variation of contamination as reflected by differences in egg concentrations between colonies
Gannet eggs were collected from Ailsa Craig (AC), a granite island situated in the outer side of the Firth of Clyde on the west coast of Scotland, and from Bass Rock (BR), located in the outer part of the Firth of Forth on the east coast of Scotland, in the North Sea
Summary
Perfluoroalkyl substances (PFAS) are man-made compounds, produced since the 1950s and, historically considered unreactive. PFAS are chemically and thermally stable due to their chemical structure and, because of their surfactant properties, they provide stain, water and oil resistance (Kissa, 2001) They have been extensively used in a diverse range of industrial and domestic applications (Giesy and Kannan, 2002; Prevedouros et al, 2006; Renner, 2001). The presence of PFAS in the environment originates from direct usage and from environmental transformation of other labile perfluoralkyl compounds (Giesy and Kannan, 2001; Zhao et al, 2015) Due to their chemical stability, they are recalcitrant to degradation and metabolism and can be subject to long-range transportation (Kannan et al, 2005). PFOS is considered the most important PFAS because of its high volume production, toxicity, widespread distribution and persistence
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
