Organohalogen concentrations and a gross and histologic ...

Table 3A
Levels of ∑-PCBs (ng/g l.w.) and their toxic effects compared to the 23-year-old female polar bear with enlarged clitoris. Abbreviations:
LOAEL: Lowest Observed Adverse Effect Level; NOAEL: No Adverse Effect Levels; NOEL: No Observed Effect Level; EC50:
Effect Concentration of 50% (data from de March et al., 1998).
188
Level Species Effect (tissue) Female with enlarged clitoris
500 Human LOAEL short term memory 3 033
1 000 Human NOAEL visual memory 3 033
4 000 Otter Vitamin A reduction (liver) 3 033
7 500 Otter NOEL reproduction 3 033
9 000 Mink NOEL kit survival 3 033
11 000 Otter Vitamin A reduction (liver) 3 033
16 500 Harbour seal Immunosuppression, depressed vitamin A 3 033
21 000 Rhesus monkey LOAEL immune effects 3 033
25 000 Harbour seal Poor reproductive success 3 033
40 000 Mink EC50 litter size 3 033
60 000 Mink EC50 litter size 3 033
77 000 Ringed seal Poor reproductive success 3 033
80 000 Mink EC50 kit survival 3 033
120 000 Mink EC50 kit survival 3 033
Table 3B
Levels of known ∑-TEQ values (PCDDs/Fs, nPCBs; for otter also mono-ortho PCBs) and their toxic effects compared to the 23-yearold
female polar bear with enlarged clitoris. Abbreviations: NOEL: No Observed Effect Level; LOAEL: Lowest Observed Adverse
Effect Level; EC50/90: Effect Concentration of 50/90% (data from de March et al., 1998, AMAP, 2004). All TEQ values in pg/g w.w.
(wet weight) or pg/g l.w. (lipid weight).
TEQ Level Species Effect (tissue analysed) Female with enlarged clitoris (tissue)
69 l.w. Harbour seal Immunosuppression 3.78 pg/g l.w. (liver)
84 w.w Otter NOEL for vitamin A reduction (liver) 3.78 pg/g l.w. (liver)
160 w.w. Mink EC50 litter size (muscle) 3.78 pg/g l.w. (liver)
200 w.w. Mink Kit survival (muscle) 3.78 pg/g l.w. (liver)
490 w.w. Mink Kit survival (liver) 3.78 pg/g l.w. (liver)
490 w.w. Mink LOAEL for mink kit survival (liver) 3.78 pg/g l.w. (liver)
520 l.w. Marine mammals Hepatic vitamin A stores (liver) 3.78 pg/g l.w. (liver)
520 l.w. Marine mammals Thyroid hormone concentrations (liver) 3.78 pg/g l.w. (liver)
520 l.w. Marine mammals Immunosuppression (liver) 3.78 pg/g l.w. (liver)
5000 l.w. Otter EC90 for vitamin A reduction (liver) 3.78 pg/g l.w. (liver)
Skull
Untreated hyperadrenocorticism due to 21-hydroxylase deficiency can result
in pseudohermaphroditism and decline in bone mineral density (osteoporosis)
(Acland 1995, Feldman 1995, Mickelsen and Memon 1995, Valentino et
al., 2000) and also, anthropogenic pollutants (e.g., OCs) have been positively
correlated to metabolic bone diseases (osteoporosis) in mammalian wildlife
(Zakharov and Yablokov 1990, Bergman et al., 1992, Mortensen et al., 1992,
De Guise et al., 1995, Schandorff 1997a-b, Lind et al., 2003). Therefore bone
mineral density (BMD) in the female polar bear skull was examined to detect
osteopenia or osteoporosis as a possible effect of endocrine disruption
caused by high organohalogen exposure. The BMD of the aberrant female
polar bear was close to the mean value found in a representative reference
group of 16 adult female polar bears (age 5-23 years) from East Greenland