PARENT SESSION
46 - Surface Water Pollution
8:00 AM to 6:30 PM, Tuesday, 14 May 2002
Exhibition Area

(46-02) PCB transfer from mother to pup during lactation in UK grey seal (Halichoerus grypus).

Thomé, Jean-Pierre^*,1, Debier, Cathy², Pomeroy, Paddy³, Dupont, Cédric¹, Larondelle, Yvan², ¹ University of Liège, Laboratory of Animal Ecology and Ecotoxicology, 22 Quai Van Beneden, Liège, Belgium² Université Catholique de Louvain, Laboratoire de Biochimie de la Nutrition, Place Croix du Sud 2/8, Louvain-la-Neuve, Belgium³ University of St. Andrews, Gatty Marine Laboratory, Sea mammal Research Unit, Fife, United Kingdom

ABSTRACT- Top predators such as seals could accumulate fat-soluble xenobiotics like PCBs which are known to induce several kinds of negative effects, especially on immunity, vitamins status and on reproduction according to their endocrine disruptor properties. The transfer of PCBs from mother to pup was measured in free-ranging grey seals from the Isle of May (Scotland) during lactation. Mother-pup pairs (9 in 1998 and 14 in 2000) were captured several times (up to 6 times) between birth and weaning to collect milk, blood (mother and pup) and blubber (mother) samples from several lactation stages. The transfer of PCBs from mother to pup seemed to occur mainly at late lactation. Indeed, milk PCB concentration stayed constant during the first part of lactation (310 g/kg) and increased at late lactation (715 g/kg). This must be related with the PCB contamination level of the mother serum which increased at early (7 g/l serum at day 0) and late lactation (13 g/l serum). PCB concentrations in new born pup were as high or higher than in mother serum (13 g/l serum) indicating a placental transfer. At late lactation, the PCB concentration in pup serum (30 g/l serum) was much greater than in mother serum according to consumption of contaminated milk. The PCB transfer from blubber to mother serum and milk are further discussed. The PCB pattern in the various compartments of transfer (mother blubber, serum, milk and pup serum) was mainly constituted of congeners 101, 138,153, 170, 180 and 187 which made up 85 % of the total PCB body burden. The dynamic of transfer of individual PCB congeners between mother and pup is discussed.

Key words: PCBs, Grey seal, lactation