Characterization and Interpolation of Sediment Polychlorinated Biphenyls and Polybrominated Diphenyl Ethers in Resident Killer Whale Habitat along the Coast of British Columbia, Canada

The northeastern Pacific northern and southern resident killer whale (Orcinus orca) populations are listed as threatened and endangered in Canada, respectively, with persistent, bioaccumulative contaminants, such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), posing threats to their recovery. Concentrations of PCBs and PBDEs in subtidal surface sediments collected from 97 sites along the British Columbia (BC) coast were used to identify their distribution and profiles, and to assess killer whale habitat quality. Victoria Harbour (VH3(site ID: 1)) sediments exhibited the highest PCB and PBDE concentrations. For PCBs, PCB‐138 was found at the highest concentration, followed by PCB‐153, PCB‐110, PCB‐149, PCB‐101, and PCB‐118. For PBDEs, individual congeners were ranked as follows: BDE‐209 > BDE‐207 > BDE‐206 > BDE‐208 > BDE‐47 > BDE‐99. Principal component analyses (PCA) illustrated the variations in contaminant profiles, with PC1 for PCBs and PBDEs correlated with the octanol‐water partition coefficient (log KOW, p