Polychlorinated biphenyls and reproductive hormones in female polar bears at Svalbard

• Main Authors: Skaare, J.U., Wiig, Ø., Haave, M., Dahl, E., Lie, E., Ropstad, E., Derocher, A.E.
• Format: Other/Unknown Material
• Language: English
• Published: 2003
• Subjects: Pollution; Endocrine disruption; Populations; Estradiol; Barents Sea; Arctic; Progesterone; Endocrine disruptors; Svalbard
• Online Access: https://era.library.ualberta.ca/items/00d5cb43-1f46-48ef-ad15-8b2c27e23103; https://doi.org/10.7939/R3CP05

High concentrations of polychlorinated biphenyls (PCBs) in polar bears from Svalbard have increased concern for that population’s reproductive health. We examined whether there were associations between the plasma concentrations of PCBs and reproductive hormones [progesterone (P4) and 17β-estradiol (E2)] in free-living female polar bears from Svalbard. Concentrations of P4 depended on reproductive status, and concentrations were lowest in females with offspring— females with cubs and females with yearlings. In these females, the P4 concentrations were positively correlated with plasma ΣPCBs (sum of all analyzed polychlorinated biphenyl congeners) concentrations. The ΣPCBs concentrations explained 27% of the variation in the P4 concentrations. There were no correlations between ΣPCBs and E2 and cortisol in any of the groups of polar bears, or between ΣPCBs and P4 in single polar bears. Although the ΣPCBs–P4 relationship in female polar bears with offspring is not evidence per se of a direct cause–effect association, the results indicate that PCBs may affect levels of P4 in polar bear females. There is a clear need to further assess the hormone balance and population health of polar bears at Svalbard. Key words: Arctic, Barents Sea, endocrine disruption, endocrine disruptors, estradiol, pollution, population, progesterone, Svalbard.