Persistent organic pollutants in the diet of harbor seals (Phoca vitulina) inhabiting

• Main Authors: Donna L Cullon, Steven J Jeffries, Peter S Ross
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2005
• Subjects: Canada; Phoca vitulina
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.1047.8611; http://faculty.wwu.edu/%7Eshulld/ESCI%20432/Cullon2005PCB.pdf

Abstract-Harbor seals (Phoca vitulina) inhabiting Puget Sound (WA, USA) recently were found to be seven times more contaminated with polychlorinated biphenyls (PCBs) than those inhabiting the adjacent Strait of Georgia (BC, Canada). We carried out a food basket approach to approximate realistic dietary exposures of both new (e.g., polybrominated diphenyl ethers [PBDEs]) and legacy (e.g., dichlorodiphenyltrichloroethane [DDT]) persistent organic pollutants (POPs) for these harbor seals. Food basket homogenates, each consisting of over 200 individual prey items, were constructed using documented dietary preferences for harbor seals in these basins, and analyzed for organochlorine pesticides, flame retardants, and other persistent contaminants. Concentration rankings for the major contaminant classes in the Puget Sound food basket were ⌺PCBs Ͼ ⌺PBDEs Ͼ ⌺DDT, and for the Strait of Georgia food basket were ⌺PCBs Ͼ ⌺DDT Ͼ ⌺PBDEs, highlighting the emergence of PBDEs as a significant concern in the regional environment. Consistent with observations in harbor seals, PCB concentrations in the Puget Sound food basket were seven times higher than in its Strait of Georgia counterpart. Based on our food basket results, the estimated daily intake of ⌺PCB toxic equivalents to dioxin by Puget Sound harbor seals exceeds some wildlife consumption guidelines for PCBs. Our results indicate that both legacy and new POPs present a health risk to these marine mammals.