ORGANOCHLORINES IN MOTHER AND PUP PAIRS IN 2 ARCTIC SEAL SPECIES - HARP SEAL (PHOCA-GROENLANDICA) AND HOODED SEAL (CYSTOPHORA-CRISTATA)

During the lactation period of two Arctic seal species, pairs of femal es with their respective pups were caught in the 'West Ice', a pack ic e area in the Greenland Sea north of Jan Mayen. Blubber samples from p airs of harp seals (Phoca groenlandica) and hooded seals (Cystophora c ristata) were analysed for 22 CB-congeners (Sigma CB), five DDT compon ents (Sigma DDT), four chloradane-related compounds (Sigma CHL), three HCH isomers (Sigma HCH) and HCB using capillary GC-ECD in order to st udy interspecies differences and generation transfer of organochlorine (OC) pollutants. Highest concentrations of these OCs were found in ad ult hooded seals where average concentrations in blubber were 4.63 mu g g(-1) Sigma CB, 2.83 mu g g(-1) Sigma DDT and 0.98 mu g g(-1) Sigma CHL, representing five, four and two times the concentration found in adult harp seals, respectively. On the other hand, Sigma HCH and HCB l evels in adult harp seals were higher or the same as in hooded seals. Different food preference is probably the major factor causing the obs erved interspecies OC level variations. However, species-specific deto xification may also contribute to these results. An efficient generati on transfer of OCs was found in bath species. However, this transfer s eemed to be selective with respect to OC-groups and certain CB congene rs. Concentrations of highly chlorinated CB congeners were relatively less present in pups of both species. An increasing transfer barrier i n the order: Sigma HCH approximate to HCB < Sigma CHL less than or equ al to Sigma DDT < Sigma CB seems to exist. The generation transfer of OCs demonstrates the importance of lactation as an excretory retire of various CB congeners ann pesticides in reproductive female seals but, more important, it demonstrates the need for a better understanding o f the consequences this transfer might have for the young animals. (C) 1997 Elsevier Science Ltd.