Organohalogen concentrations and a gross and histologic ...

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Chapter 6
East Greenland polar bear reproductive
organs sampled 1999-2002
For the present investigation, reproductive organs were sampled from both
females and males. Due to time constrains, only data on sexual organs from
the female polar bears are presented in this thesis. However, the penis was
investigated macroscopically before the bacula were prepared for the analysis
of bone mineral density (BMD, see Chapter 3). The results from the
analyses of female sexual organs are described in details in paper VI.
Pseudohermaphroditic female polar bears?
During helicopter surveys from 1990 to 1997 at Svalbard, Norwegian researchers
found 4 presumed female pseudohermaphrodite polar bears (Wiig
et al. 1998). The four bears – two adults and two sibling yearlings – exhibited
severe clitoral enlargement and a morphological investigation by digital
manipulation (palpation) revealed a baculum in the two siblings. No signs of
baculum were found in the two adult females, but in the siblings the penislike
clitoris possibly contained a baculum and was additionally placed more
caudally than is normal. The urethral opening in these siblings was placed
laterally. Due to the protection of bears at Svalbard, the researcher could not
investigate the entire reproductive tract and take samples for histology. As
mentioned earlier, polar bears in East Greenland and Svalbard are among
the most polluted bears in the Arctic, and therefore it was suspected that the
clitoral enlargement at Svalbard could be a result of endocrine disruption
due to ”hormone-like” organohalogens (e.g. PCBs and DDTs) causing pseudohermaphroditism
(e.g. Benirschke 1981, Polani 1981, Acland 1995, Capen
1995, Feldman 1995, Hunter 1995, Mickelsen and Memon 1995, Wiig et al.
1998). A definition of a pseudohermaphrodite is: ”an individual with apparently
healthy gonads of only one sex but which also has some traits of the
opposite sex" (Anon. 1994).
Based on the above finding we focused on the female reproductive tract in
the present investigation of East Greenland polar bear genitalia. The 9th of
July 1999 we were lucky to obtain samples from a 23-year-old female polar
bear, exhibiting an abnormally large clitoris, caught outside Scoresby Sound
(Fig. 9). Samples for histology were taken from the reproductive tract for a
first time evaluation of clitoral enlargement in polar bears.