Temporal Trends (1981-2013) of per- and polyfluoroalkyl substances and total fluorine in Baltic cod (Gadus morhua).
By Lara Schultes, Oskar Sandblom, Katja Broeg, Anders Bignert, and Jonathan P Benskin
Environ. Toxicol. Chem.
October 22, 2019
Temporal trends from 1981 to 2013 of 28 per- and polyfluoroalkyl substances (PFASs) were investigated in liver tissue of cod (Gadus morhua) sampled near southeast Gotland, in the Baltic Sea. A total of 10 PFASs were detected, with ∑ PFAS geometric mean concentrations ranging from 6.03 to 23.9 ng/g ww. Perfluorooctane sulfonate (PFOS) was the predominant PFAS and increased at a rate of 3.4% per year. Most long-chain perfluoroalkyl carboxylic acids increased at rates of 3.9-7.3% per year except for perfluorooctanoate (PFOA), which did not change significantly over time. The perfluoroalkyl acid precursors perfluorooctane sulfonamide (FOSA) and 6:2 fluorotelomer sulfonic acid were detected, of which the former (FOSA) declined at a rate of -4.4% per year, possibly reflecting its phase out starting in 2000. An alternate time trend analysis from 2000 to 2013 revealed slightly different trend rates; for most compounds increasing at slower rates compared to their trends measured over the entire period. An exception was perfluorohexane sulfonate (PFHxS), increasing at a faster rate of 3.7% measured from 2000 on compared to the 3.0% per year measured starting from 1981. Analysis of the total fluorine (TF) content of the samples disclosed large amounts of unidentified fluorine; however, its composition (organic or inorganic) remains unclear. Significant negative correlations between concentrations of individual PFASs (with the exception of PFOS) and liver somatic index. Additionally, body length was negatively correlated with PFOA and PFNA but positively correlated with perfluorododecanoate (PFDoDA) and FOSA. Additional studies on endocrine, immunological, and metabolic effects of PFAS in marine fish are essential to assess the environmental risk of these substances. This article is protected by copyright. All rights reserved.