A baseline study of perfluorochemicals in Franciscana dolphin and Subantarctic fur seal from coastal waters of Southern Brazil

Abstract

Two major classes of PFCs, perfluoroalkylsulfonates and perfluoroalkylcarboxylates represented by perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA), respectively, have become contaminants of concern, due to their widespread distribution, in humans and wildlife, persistence and biological effects (Giesy and Kannan, 2001; Kannan et al., 2004, 2006; Houde et al., 2006). PFCs are used as surfactants due to their surface active characteristics imparted by oleophobic and hydrophilic moieties of the perfluorochemical structure. These chemicals have found commercial usage as refrigerants, production of fluoropolymers, surfactants, and as components of pharmaceuticals, fire retardants, adhesives, lubricants, cosmetics, paper coating, insecticides, among others. PFCs have been detected in different biological samples such as fish, birds, marine mammals and human blood from North America (Kannan et al., 2004; Houde et al., 2006; Sinclair et al., 2006), Japan (Nakata et al., 2006), Arctic (Kannan et al., 2005) and Europe (Kannan et al., 2002; Van de Vijver et al., 2007). Despite the environmental significance of PFCs and the detection of these compounds in many countries around the world, very few studies have reported the occurrence of PFCs in South America including the Southern Oceans (Tao et al., 2006). A recent survey showed that fish and birds from Colombia, South America, contained notable concentrations of PFOS (Olivero-Verbel et al., 2006); human blood from Brazil and Colombia contained notable concentrations of PFCs (Kannan et al., 2004). In this study, concentrations of 10 PFCs, namely, PFOS, perfluorohexanesulfonate (PFHxS), perfluorodecanesulfonate (PFDS), perfluorooctane sulfonamide (PFOSA), perfluoroheptanoic acid (PFHpA), PFOA, perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnDA), and perfluorododecanoic acid (PFDoDA) were determined in 35 liver samples from two marine mammal species (Pontoporia blainvillei; Franciscana dolphin and Arctocephalus tropicalis; Subantarctic fur seal) collected from Southern Brazil to