Organohalogen concentrations and a gross and histologic ...

SC
II
PC/LC
Figure 2
The histology of the enlarged clitoris from the 23-year-old female polar bear shot in Scoresby Sound, central East Greenland, 1999.
The ulcerated part of glans clitoridis is covered by serocellular crust (SC). The tissue is highly vascularized and there is intense
inflammation (II) dominated by plasma cells (PC) and lymphocytes (LC), severe fibrosis (SF) and thrombosed capillaries (TC). Left:
HE, 10x. Right: HE, 20x.
and Scott 1993). The initial cause of the lesions can not be determined, but it
is probable that some sort of trauma (e.g. mating, vestibulitis or vaginitis)
have caused the first lesions. Subsequently, licking and biting of the lesions
by this individual bear have caused further epithelial damage and persisting
inflammatroy reaction with formation of granulated tissue. There was no
signs of hyperplasia in the clitoral enlargement and therefore the female
polar bear was not a pseudohermaphrodite (i.e. the enlargement was not
due to endocrine disruption from androgen or antiestrogen exposure).
The uterine glands (crypts) were highly developed, indicating that this female
had been in gestation earlier. Histological examination of the liver,
kidneys, adrenals, spleen and lymph nodes showed only minor and insignificant
changes (mainly mononuclear cell infiltrates) (Sonne et al., submitted-a,b).
Concentrations of OCs and potential effects
Organohalogens
Levels of ∑PCBs, ∑PBDEs, ∑DDTs, ∑HCHs and ∑CHLs in the adipose tissue
of the 23-year-old female polar bear were compared with levels in 23
adult female polar bears (age: 5-25 years) from East Greenland (1999-2002)
(Table 2). The concentrations of OHCs in this bear did not differ significantly
from those in the reference group (all: p>0.05) except for ∑PCBs, which was
slightly lower (p=0.04) (Table 2). ∑MeSO 2 -PCB and 3-MeSO 2 -4,4’-DDE concentrations
were not included in these comparisons due to covariance, i.e.,
∑-MeSO 2 -PCB to ∑-PCBs and 3-MeSO 2 -4,4’-DDE to 4,4’-DDE ratios for the
present Greenland bears were relatively constant values of 0.08 ± 0.03 and
0.06 ± 0.05, respectively (Sandala et al., 2004). Additional information on OC
concentrations and information on sex, season differences and time trends in
the East Greenland polar bear are available in Dietz et al., (2004) and Sandala
et al., (2004).
Recent studies on polar bears from Svalbard have correlated high levels of
OCs to disruption of retinol (vitamin A), thyroid, sex steroids and cortisol
levels in blood (Skaare et al., 2001; Haave et al., 2003, Oskam et al., 2003,
2004) while other polar bear studies have indicated that high levels of OCs
have a negative effect on IgG levels suggesting possible immunotoxic effects
SF
TC
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