Polychlorinated biphenyls (PCBs), chlorinated pesticides (i.e., dichlorodiphenyltrichloroethane (DDT) and its metabolites, chlordanes (CHLs), dieldrin, hexachlorobenzene (HCB), and mirex), polybrominated diphenyl ethers (PBDEs), perfluorinated chemicals (PFCs), and polyaromatic hydrocarbons (PAHs) were measured in blubber biopsy samples collected from 139 wild bottlenose dolphins (Tursiops truncatus) during 2003-2005 in Charleston (CHS), SC and the Indian River Lagoon (IRL), FL Dolphins accumulated a similar suite of contaminants with Sigma PCB dominating (CHS 64%, IRL 72%), followed by Sigma DDT (CHS 20%, IRL 17%), Sigma CHLs (CHS 7%; IRL 7%), Sigma PBDE (CHS 4%, IRL 2%), PAH at 2%, and dieldrin. PFCs and mirex each 1% or less. Together Sigma PCB and Sigma DDT concentrations contributed similar to 87% of the total POCs measured in blubber of adult males. Sigma PCBs in adult male dolphins exceed the established PCB threshold of 17 mg/kg by a 5-fold order of magnitude with a 15-fold increase for many animals; 88% of the dolphins exceed this threshold. For male dolphins, CHS (93,980 ng/g lipid) had a higher Sigma PCBs geomean compared to the IRL (79,752 ng/g lipid) although not statistically different. In adult males, the PBDE geometric mean concentration was significantly higher in CHS (5920 ng/g lipid) than the IRL (1487 ng/g). Blubber Sigma PFCs concentrations were significantly higher in CHS dolphins. In addition to differences in concentration of PCB congeners, Sigma PBDE, TEQ Sigma CHLs, mirex, dieldrin, and the ratios Sigma DDE/Sigma DDT and trans-nonachlor/cis-nonachlor were the most informative for discriminating contaminant loads in these two dolphin populations. Collectively, the current Sigma PCB, Sigma DDT, and Sigma PBDEs blubber concentrations found in CHS dolphins are among the highest reported values in marine mammals. Both dolphin populations, particularly those in CHS, carry a suite of organic chemicals at or above the level where adverse effects have been reported in wildlife, humans, and laboratory animals warranting further examination of the potential adverse effects of these exposures. Published by Elsevier B.V.
