Concentrations of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and
dibenzofurans (PCDD/Fs), and polybrominated diphenyl ethers (PBDEs) were examined as a function of depth in
killer whale (
Orcinus orca
) blubber samples. Lipid-normalized concentrations of PCBs, PCDD/Fs, and PBDEs did
not display significant variation with depth in three distinct blubber layers (outer, central, and inner). Significantly
more variation in contaminant concentrations were observed with depth on a wet weight basis for the killer whale
sample. The current study indicates that non-invasive microdart biopsy sampling methods commonly used for
monitoring contaminants in marine mammals yield representative details on contaminant burdens for chlorinated
and brominated aromatic compounds in marine mammal blubber, regardless of the quantity and type of blubber
sampled, provided that lipid normalization is performed on resulting analytical determinations.
