Tissue distribution of polychlorinated naphthalenes (PCNs) and non-ortho chlorinated bipbenyls (non-ortho CBs) in harbour porpoises (Phocoena phocoena) from Swedish waters

Polychlorinated naphthalenes (PCNs) and non-ortho chlorinated biphenyls (no n-ortho CBs) were analysed in blubber, nuchal fat, liver, muscle, kidney an d brain of three male harbour porpoises (Phocoena phocoena) from the west c oast of Sweden. To estimate spatial variation, PCNs and non-ortho CBs were analysed in six blubber samples collected at different anatomical sites of each animal. Highest wet weight concentrations of Sigma PCNs were detected in the lipid rich tissues (blubber and nuchal fat) and liver (520-730 and 5 20 pg/g, respectively) and lowest in brain (22 pg/g). TetraCNs were most ab undant in muscle, kidney and brain, while the hexaCNs were most abundant in the lipid rich tissues and liver. The highest lipid weight concentration r ecorded (11 ng/g) was for the hexaCN congeners no. 66/67 in liver. These co eluting hexaCN congeners accounted for 80-100% of total hexaCNs in all tiss ues examined. Concentrations of Sigma non-ortho CBs were highest in lipid rich tissues (2 20-280 pg/g wet weight). Non-ortho CB no. 77 and 169 constituted between 62 -86% and 4.9-9.3%, respectively, of total Sigma non-ortho CBs. No major var iation of Sigma non-ortho CB concentrations was found between the six diffe rent blubber sites but higher Sigma PCN concentrations (wet weight) were fo und dorsally at the peduncle. Toxic equivalent concentrations (TEQs) showed that non-ortho CB no. 126 was the main contributor to total TEQs in all ti ssues, except liver in which hexaCN congener nos. 66/67 contributed to abou t 50% of total TEQs. (C) 2000 Elsevier Science Ltd. All rights reserved.