Concentrations of perfluorinated carboxylic acids (PFCAs) and sulfonic acids (PFSAs), such as including perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA), in liver of two species of marine mammals (Pontoporia blainvillei and Arctocephalus tropicalis) sampled in Southern coast of Brazil from 2000 to 2004. Samples were were homogenized, extracted with methyl tert-butyl ether (MTBE), evaporated to near-dryness under a stream of nitrogen, reconstituted with methanol, and analyzed by a Agilent 1100 series high-performance liquid chromatography (HPLC) coupled with an Applied Biosystems API 2000 electrospray triple-quadrupole mass spectrometer (ESI-MS/MS).