Polychlorinated biphenyls and reproductive hormones in female polar bears at Svalbard.
Author(s) -
Marte Haave,
Erik Ropstad,
Andrew E. Derocher,
Elisabeth Lie,
Ellen Dahl,
Øystein Wiig,
Janneche Utne Skaare,
Bjørn Munro Jenssen
Publication year - 2002
Publication title -
environmental health perspectives
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.257
H-Index - 282
eISSN - 1552-9924
pISSN - 0091-6765
DOI - 10.1289/ehp.5553
Subject(s) - offspring , hormone , population , polar , biology , endocrinology , polychlorinated biphenyl , reproduction , physiology , chemistry , medicine , ecology , pregnancy , environmental health , genetics , physics , astronomy
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 17 beta-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 sigma PCBs (sum of all analyzed polychlorinated biphenyl congeners) concentrations. The sigma PCBs concentrations explained 27% of the variation in the P4 concentrations. There were no correlations between sigma PCBs and E2 and cortisol in any of the groups of polar bears, or between sigma PCBs and P4 in single polar bears. Although the sigma PCBs-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.
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