| Summary: | Published by PLoS ONE and copyright of Peterson et al. The definitive version of this article is available at: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0096191 Persistent organic pollutants, including polychlorinated biphenyls (PCBs), are widely distributed and detectable far from anthropogenic sources. Northern elephant seals (Mirounga angustirostris) biannually travel thousands of kilometers to forage in coastal and open-ocean regions of the northeast Pacific Ocean and then return to land where they fast while breeding and molting. Our study examined potential effects of age, adipose percent, and the difference between the breeding and molting fasts on PCB concentrations and congener profiles in blubber and serum of northern elephant seal females. Between 2005 and 2007, we sampled blubber and blood from 58 seals before and after a foraging trip, which were then analyzed for PCBs. Age did not significantly affect total PCB concentrations; however, the proportion of PCB congeners with different numbers of chlorine atoms was significantly affected by age, especially in the outer blubber. Younger adult females had a significantly greater proportion of low-chlorinated PCBs (tri-, tetra-, and penta-CBs) than older females, with the opposite trend observed for hepta-CBs, indicating that an age-associated process such as parity (birth) may significantly affect congener profiles. The percent of adipose tissue had a significant relationship with inner blubber PCB concentrations, with the highest mean concentrations observed at the end of the molting fast. These results highlight the importance of sampling across the entire blubber layer when assessing contaminant levels in phocid seals and taking into account the adipose stores and reproductive status of an animal when conducting contaminant research This research was conducted as part of the Tagging of Pacific Predators (TOPP) program and was supported in part by the National Ocean Partnership Program (N00014-02-1-1012); the Office of Naval Research (N00014-00-10880, N00014-03-1-0651, N00014-08-1-1195, and N00014-10-1-0356); the E&P Sound and Marine Life Joint Industry Project of the International Association of Oil and Gas Producers (JIP2207???23); the Moore, Packard, and Sloan Foundations; the Ida Benson Lynn Endowed Chair in Ocean Health; Steve Blank. Full funding for Open Access provided by the University of California, Santa Cruz Open Access Fund. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
|
|---|