Perfluorooctanesulfonate and Related Fluorinated Hydrocarbons in Marine Mammals, Fishes, and Birds from Coasts of the Baltic and the Mediterranean Seas KannanKurunthachalam CorsoliniSimonetta FalandyszJerzy OehmeGünter FocardiSilvano GiesyJohn P. 2002 Perfluorooctanesulfonate (PFOS; C<sub>8</sub>F<sub>17</sub>SO<sub>3</sub><sup>-</sup>), perfluorooctanesulfonamide (FOSA; C<sub>8</sub>F<sub>17</sub>SO<sub>2</sub>NH<sub>2</sub>), perfluorohexanesulfonate (PFHxS; C<sub>6</sub>F<sub>13</sub>SO<sub>3</sub><sup>-</sup>), and perfluorooctanoate (PFOA; C<sub>7</sub>F<sub>15</sub>CO<sub>2</sub><sup>-</sup>) were detected in 175 samples of liver and blood of bluefin tuna (<i>Thunnus thynnus</i>), swordfish (<i>Xiphias gladius</i>), common cormorants (<i>Phalacrocorax carbo</i>), bottlenose dolphins (<i>Tursiops truncatus</i>), striped dolphins (<i>Stenella coeruleoalba</i>), common dolphins (<i>Delphinus delphi</i>), fin whales (<i>Balenoptera physalus</i>), and long-finned pilot whales (<i>Globicephala melas</i>) from the Italian coast of the Mediterranean Sea and in livers of ringed seals (<i>Phoca hispida</i>), gray seals (<i>Halichoerus grypus</i>), white-tailed sea eagles (<i>Haliaeetus albicilla</i>), and Atlantic salmon (<i>Salmo salar</i>) from coastal areas of the Baltic Sea. PFOS was detected in all of the wildlife species analyzed. Concentrations of PFOS in blood decreased in order of bottlenose dolphins > bluefin tuna > swordfish. Mean PFOS concentrations (61 ng/g, wet wt) in cormorant livers collected from Sardinia Island in the Mediterranean Sea were less than the concentrations of PFOA (95 ng/g, wet wt). PFOS concentrations in cormorant livers were significantly correlated with those of PFOA. FOSA was found in 14 of 19 livers or blood samples of marine mammals from the Mediterranean Sea. The highest concentration of 878 ng FOSA/g, wet wt, was found in the liver of a common dolphin. Livers of ringed and gray seals from the Bothnian Bay in the Baltic Sea contained PFOS concentrations ranging from 130 to 1100 ng/g, wet wt. No relationships between PFOS concentrations and ages of ringed or gray seals were observed. Concentrations of PFOS in livers of seals were 2.7−5.5-fold greater than those in corresponding blood. A significant positive correlation existed between the PFOS concentrations in liver and blood, which indicates that blood can be used for nonlethal monitoring of PFOS. Trend analysis of PFOS concentrations in livers of white-tailed sea eagles collected from eastern Germany and Poland since 1979 indicated an increase in concentrations during the 1990s. Livers of Atlantic salmons did not contain quantifiable concentrations of any of the fluorochemicals monitored. PFOS is a widespread contaminant in wildlife from the Baltic and the Mediterranean Seas, while FOSA and PFOA were detected only in certain locations indicating their sporadic spatial distribution.