Polychlorinated biphenyls and organochlorine compounds in brain, liver and muscle of beluga whales (Delphinapterus leucas) from the Arctic and St. Lawrence estuary

Brain, liver and muscle samples from seven male beluga whales, Delphinapterus leucas, from Hendrickson Island in the Canadian Arctic (n=3) and the St. Lawrence River estuary (n=4), were analyzed for polychlorinated biphenyls (PCBs) and other organochlorine (OC) compounds to determine whether there are differences in the distribution of these contaminants in beluga tissues and between geographic locations. Wet weight concentrations of ΣPCB, ΣDDT, Σchlordane and mirex were significantly higher (p<0.05) in St. Lawrence samples. Principal component analysis (PCA) of the PCB and OC data indicated that contaminant profiles in belugas from the St. Lawrence reflect point-source inputs of these compounds while Arctic samples appear to be dominated by PCB congeners and OC compounds subject to long-range transport and deposition. Discriminant functions analysis of the contaminant data for the brain, liver and muscle tissues indicated that the distributions of OC compounds in the liver and muscle tissues were very similar, while brain samples could be distinguished from other tissues by differences in PCB congener patterns and higher concentrations of Σhexachlorocyclohexane (ΣHCH), primarily αHCH.