Correlations between per- and polyfluoroalkyl substances (PFASs) and body morphometrics in fledgling shearwaters impacted by plastic consumption from a remote Pacific island

This study investigated the concentrations of 45 per‐ and polyfluoroalkyl substances (PFASs) in fledgling Flesh‐footed Shearwater (Ardenna carneipes; n = 33) and Wedge‐tailed Shearwater (A. pacifica; n = 9) livers via LC‐MS/MS and their relationship to body morphometrics and ingested plastic mass recorded in 2019 on Lord Howe Island, NSW, Australia. Sixteen PFASs were detected, of which perfluorooctanesulfonate (PFOS) was the dominant compound, detected in 100% of birds (1.34 to 13.4 ng/g ww). Long‐chain perfluorocarboxylic acids, including perfluorodecanoic acid (PFDA; <0.04 to 0.79 ng/g ww) and perfluorotridecanoic acid (PFTrDA; <0.05. to 1.6 ng/g ww) were detected in >50% of birds. There was a positive correlation between PFDA and PFTrDA concentrations and wing chord length (R_s=0.36, p=0.0204; R_s=0.44, p=0.0037 respectively), and between PFDA concentrations and total body mass (R_s=0.33, p=0.032) suggesting that these compounds may impact shearwater fledgling morphometrics. Plastic was present in the intestinal tract of 79% of individuals (<7.6 g), although there was no correlation between PFAS concentrations and plastic mass, indicating ingested plastic is not the likely primary exposure source. The widespread occurrence of PFASs in fledgling marine birds from a relatively pristine location in the southern hemisphere suggests that further studies in adult shearwaters and other marine birds are warranted to investigate whether there are any long‐term physiological effects on bird species.