Levels of C-10-C-13 polychloro-n-alkanes in marine mammals from the Arcticand the St. Lawrence River estuary

Marine mammals from Various regions of the Arctic and the St. Lawrence Rive r estuary were examined for the first time for levels of C-10-C-13 polychlo ro-n-alkanes (sPCAs). Respective mean total sPCA concentrations in the blub ber of beluga whales (Delphinapterus leucas) from Saqqaq and Nuussuaq, west ern Greenland, were 0.23 +/- 0.02 (n = 2) and 0.164 +/- 0.06 mu g/g (n = 2) , similar to that in beluga from the Mackenzie Delta in the western Canadia n Arctic 0.21 +/- 0.08 mu g/g (n = 3). sPCAs levels were higher in beluga b lubber from the St. Lawrence River (0.37 to 1.4 mu g/g). Mean sPCA concentr ations in the blubber samples from walruses (Odobenus rosmarus) (Thule, nor thwest Greenland) and ringed seal (Phoca hispida) (Eureka, southwest Ellesm ere Island) were 0.43 +/- 0.06 (n = 2) and 0.53 +/- 0.2 mu g/g (n = 6), res pectively. Relative to commercial sPCA formulations, samples from the Arcti c marine mammals showed a predominance of the shorter chain length lower pe rcent chlorinated PCA congeners, the more volatile components of industrial formulations. This observation is consistent with long-range atmospheric t ransport of sPCAs to this region. The profiles of the belugas from the St. Lawrence River estuary, however, had higher proportions of the less volatil e sPCA congeners, implying that contamination to this region is probably fr om local sources.