Temporal Trends of Organochlorine- and Perfluorinated Contaminants in a Terrestrial Raptor in Northern Europe over 34 Years (1986-2019)
By Jan Ove Bustnes, Bård-Jørgen Bårdsen, Dorte Herzke, Georg Bangjord, Sophie Bourgeon, Clementine Fritsch, and Igor Eulaers
Environ Toxicol Chem
March 31, 2022
Fourteen legacy organochlorine contaminants (OCs) and twelve perfluorinated substances (PFASs) were measured in eggs of tawny owls (Strix alueco) in central Norway (1986 2019). We expected OCs to have reached stable equilibrium levels due to bans, and that recent phase-out of some PFASs would have slowed the increase of these compounds⊡ ΣOC comprised on average ~92% of the measured compounds, whereas ΣPFAS ( = 14 ng/g) accounted for ~8%. However, whereas the ΣOC/ΣPFAS ratio was ~60 in the first five years of the study, it was only ~11 in the last five years. Both OC-pesticides and polychlorinated biphenyls (PCBs) showed substantial declines over the study period (~85-98%): hexachlorocyclohexanes (HCHs) and chlordanes seemed to be levelling off, whereas p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) and hexachlororbenzene (HCB), and most PCB congeners still seemed to decline at a more or less constant rate. While the concentration of perfluorooctane sulfonic acid (PFOS), the dominating PFAS, was reduced by ~43%, other perfluorinated sulfonates (PFSAs) showed only minor changes. Moreover, the median concentrations of seven perfluorinated carboxylic acids (SPFCA ) increased ~5 fold over the study period. Perfluorononanoic acid (PFNA) and perfluoroundecanoate acid (PFUnA), however, seemed to be levelling off in recent years. In contrast, perfluorododecanoic acid (PFDoA), perfluorodecanoate acid (PFDcA), perfluorotridecanoic acid (PFTriA) and perfluorotetradecanoic acid (PFTeA) seemed to increase more or less linearily. Finally, perfluorooctanoic acid (PFOA) was increasingly likely to be detected over the study period. Hence, most legacy OCs and PFOS have not reached a lower threshold with stable background levels, and voluntary elimination of PFCAs still have not resulted in declining levels in tawny owls in central Norway. This article is protected by copyright. All rights reserved.© 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.