Organohalogen concentrations and a gross and histologic ...

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32 Table 2 Results from the comparison of FA in thirteen traits between periods (1892-1960 vs. 1961- 2002) and between age/ sex groups (subadults, adult females and adult males respectively). Note that data from trait 8 were excluded due to high measurement error. Trait 1-7: skull; trait 8-13: lower jaw. n.s.: no significant difference between the periods and age/sex groups, respectively. Trait 1892- 1960 (1) vs. 1960-2002 (2) Skull FA in mammalian wildlife Studies of FA in mammalian wildlife in relation to organohalogen pollution, have been conducted the last 15 years (e.g. Zakharov and Yablokov 1990, Pertoldi et al. 1997, Schandorff 1997a,b). Both the studies of the Danish Kattegat harbour seal (Phoca vitulina) population and the Baltic grey seal (Halichoerus grypus) population have detected differences in developmental instability over time and correlated the higher FA in skulls to the decades of pollution (ca. 1960-recent) (Zakharov and Yablokov 1990, Pertoldi et al. 1997, Schandorff 1997a,b). Of Ursid species, FA has been studied in the Yellowstone grizzly bear (Ursus arctos) (Picton et al. 1990). In this study FA was associated with genetic limitations (isolation; bottleneck) but not organohalogen pollution. It is not likely that genetic limitations should be higher in the pre-pollution period compared to the pollution period, as a relatively constant hunt has taken place over the last century and no clear change has been observed in the number of bears obtained or the areas where the hunt has taken place (Sandell et al. 2001). Controlled laboratory studies Females (F) vs. Males (M) Females (F) vs. Subadults (S) 1 1>2 n.s. F>S M>S 2 1>2 n.s. F>S M>S 3 n.s. n.s. n.s. n.s. 4 n.s. F>M n.s. n.s. 5 1>2 n.s. F>S M>S 5 n.s. n.s. n.s. n.s. 7 Lower jaw n.s. n.s. n.s. n.s. 8 1>2 . . M>S 9 n.s. n.s. n.s. n.s. 10 n.s. n.s. n.s. n.s. 11 n.s. n.s. n.s. M>S 12 1>2 n.s. n.s. n.s. 13 n.s. n.s. n.s. M>S Males (M) vs. Subadults (S) It is seen that for 6 traits (1, 2, 5, 8 and 12) FA was higher in the supposed pre-pollution perid (1892-1960) compared to the supposed pollution period (1961-2002) and that age/sex differencies was found in seven traits (1, 2, 4, 5, 8, 11 and 13). Several controlled laboratory studies have correlated FA (dental and bone) to in utero disturbances (e.g. Siegel and Doyle 1975a-c, Doyle et al. 1977, Siegel et al. 1977a-b) and therefore it could be speculated that the FA in our East Greenland polar bears could be explained by environmental factors like
temperature extremes and/or food availability (e.g. Siegel and Doyle 1975ac, Doyle et al. 1977, Siegel et al. 1977a-b, Nilsson 1994, Carrascal et al. 1998). Higher climatic fluctuations (against higher temperature) in the first period (ca. 1930 and ca. 1960) could explain lower food availability and thereby a higher degree of developmental instability in the polar bears compared to the second period (Førland 2002). However, a temperature effect is not likely, as temperatures above normal have been experienced in East Greenland during the last two decades which should limit the food resources (ringed seals) for the bears and thereby increase the FA (Ibid.). FA and organohalogen levels No clear pattern in the relationship between FA and individual level of organohalogens was found probably due to the large individual variability in contaminant levels, and because FA likely resulted from prenatal in utero disruptions and therefore rather related to contaminant exposure at the time of development than at the time of sampling. Few previous studies of mammals have linked FA to organohalogen contaminant concentrations on an individual by individual basis. Pertoldi et al. (1997) examined such correlations (DDTs and PCBs) in the Eurasian otter (Lutra lutra), but did not find a relationship between FA and individual contaminant burdens. The authors explained the lack of correlation by the high individual variability of organohalogens including seasonal patterns and sex differences which probably also is the case of the East Greenland polar bear as discussed in Chapter 1. In addition, individual sensitivity may reduce such a pattern especially if the exposure range and number of examined individuals are low. To give an impression of the levels of Σ-PCBs and Σ-DDTs in the present bears compared to levels in populations of marine mammals where period differences (non polluted and polluted respectively) were found in FA (skulls) and linked to organohalogen exposure, these are compared in Table 3. For Σ-PCBs, the levels in the polar bears were comparable to the lower levels of the Kattegat harbour seal before 1988, where effects on the FA was documented, while for Σ-DDTs the level was 2-10 times lower and it could therefore be suspected that the threshold of FA was not reached in the bears (subeffect exposure) (Blomkvist et al. 1992; Schandorff 1997a,b; Zakharov and Yablokov 1990). For the grey seals the differences were even larger. Which compounds cause FA has not been documented to date. Table 3 Range in levels of ∑-PCBs and ∑-DDTs in the blubber (µg/g l.w.) believed to cause FA in juvenile, subadult and adult Kattegat harbour seals (Phoca vitulina) and Baltic grey seals (Halichoerus grypus) populations from before and around 1988 compared to the East Greenland polar bears in the present study. n: number of observations (data from: Blomkvist et al. 1992; Schandorff 1997a,b and Zakharov and Yablokov 1990). Study Compound n Concentration Range in East Greenland polar bear adipose tissue (n) Kattegat harbour seal ∑-PCBs 38 6-110 1-20 (77) Kattegat harbour seal ∑-DDTs 38 2.0-13 0.1-1.1 (77) Baltic grey seal ∑-PCBs 37 32-5300 1-20 (77) Baltic grey seal ∑-DDTs 37 11.0-1600 0.1-1.1 (77) 33
Page 1 and 2: National Environmental Research Ins
Page 3 and 4: National Environmental Research Ins
Page 5 and 6: Contents Summary 7 Resumé 11 Prefa
Page 7 and 8: Paper III-b Periodontitis and tooth
Page 9 and 10: Summary Marine mammals in the Arcti
Page 11 and 12: elations between histological chang
Page 13 and 14: Resumé Betydelige mængder svært
Page 15 and 16: signifikante relationer blev fundet
Page 17 and 18: Preface Since ca. 1960 signficant a
Page 19 and 20: Acquarone, Poul Johansen and Inge B
Page 21 and 22: Abbreviations ∑ Sum of congeners
Page 23 and 24: Introduction Study area and samplin
Page 25 and 26: content and composition) varying wi
Page 27 and 28: Of the PCBs found in the East Green
Page 29 and 30: son Bay bears while the difference
Page 31 and 32: Individual levels and biological ef
Page 33: No. skulls collected 50 45 40 35 30
Page 37 and 38: Chapter 3 Bone mineral density and
Page 39 and 40: BMD analysed by DXA reflects the ar
Page 41 and 42: Table 4 Range in the levels (ng/g l
Page 43 and 44: Chapter 4 Liver histology of East G
Page 45 and 46: Table 7 Levels of ∑-PCBs, ∑-DDT
Page 47 and 48: Frequency (%) 100 80 60 40 20 Sever
Page 49 and 50: Effects of PBBs (PolyBrominated Bip
Page 51 and 52: Etiology and pathogenesis E Figure
Page 53 and 54: common sign (Acland 1995, Feldman 1
Page 55 and 56: Conclusions and final assessments O
Page 57 and 58: of CYP-450 activity that impact cir
Page 59 and 60: Regarding renal tissue, we will try
Page 61 and 62: Bernhoft, A., Ø. Wiig and J. U. Sk
Page 63 and 64: Feldman, E. C. (1995): Hyperadrenoc
Page 65 and 66: (eds.): Ringed seals in the North A
Page 67 and 68: McCormack, K. M., W. M. Kluwe, V. L
Page 69 and 70: Rosing-Asvid, A., E. W. Born and M.
Page 71 and 72: Valentino, R., S. Savastano, A. P.
Page 73 and 74: Paper I Seasonal and temporal trend
Page 75 and 76: eproductive rates of seals in the B
Page 77 and 78: concentrations of the 41 individual
Page 79 and 80: Figure 1 Capture locations of the p
Page 81 and 82: Table 4 Results of ANOVAs (F-value
Page 83 and 84: Long-Term Temporal Changes in OC Co
Page 85 and 86:
Discussion Geographical Variation i
Page 87 and 88:
sen et al. (2001) studied the trend
Page 89 and 90:
higher than reported in other studi
Page 91 and 92:
Bergman A, Olsson M. Pathology of b
Page 93 and 94:
Muir D, Norstrom RJ. Geographical d
Page 95 and 96:
Wiig Ø, Gjertz I, Hansson R, Thoma
Page 97 and 98:
Key words: polar bear, Ursus mariti
Page 99 and 100:
2. Materials and methods 2.1 Sampli
Page 101 and 102:
2.3 Age Determination The age deter
Page 103 and 104:
No. skulls collected 50 45 40 35 30
Page 105 and 106:
Table 4 Results (test and p-values)
Page 107 and 108:
Table 6 Results from F-tests (p-val
Page 109 and 110:
(oxy-chlordane, trans-chlordane, ci
Page 111 and 112:
Also Pertoldi et al. (1997) investi
Page 113 and 114:
study could not document a relation
Page 115 and 116:
Lie E, Bernhoft A, Riget FF, Beliko
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function in harbour seals (Phoca vi
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(p=0.94). Negative correlation betw
Page 121 and 122:
Osteodensitometry X-ray osteodensit
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Figure 2 BMD (g cm 2 ) in skulls fr
Page 125 and 126:
Table 3 Significant results from th
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2003) and plasma retinol and thyroi
Page 129 and 130:
Comiso JC. 2002. A rapidly declinin
Page 131 and 132:
Manalagas SC, Jilka RJ. 1995. Bone
Page 133 and 134:
Valentine DW, Soulé M. 1973. Effec
Page 135 and 136:
have the potential for adverse heal
Page 137 and 138:
Dioxin-like contaminants Extraction
Page 139 and 140:
Concentration 9000 8000 7000 6000 5
Page 141 and 142:
Acknowledgements Danish Cooperation
Page 143 and 144:
Polischuk, S. C., R. J. Letcher, R.
Page 145 and 146:
Paper IV Liver histology of free-ra
Page 147 and 148:
Histology All tissue samples were t
Page 149 and 150:
Figure 1 Hepatic lipid accumulation
Page 151 and 152:
Figure 2 Left: Portal mononuclear c
Page 153 and 154:
Relationship between histology and
Page 155 and 156:
kinson 1996). Due to these mechanis
Page 157 and 158:
sues. Arctic Monitoring and Assessm
Page 159 and 160:
van Duursen, M.B.M., Sanderson, J.
Page 161 and 162:
Introduction Polar bears (Ursus mar
Page 163 and 164:
Briefly, ∑PCBs is the sum (s) of
Page 165 and 166:
Figure 1 Bottom: example of glomeru
Page 167 and 168:
Figure 3 Tubular cell proliferation
Page 169 and 170:
Hyalin casts Hyalin casts were eval
Page 171 and 172:
Figure 6 Hyperemia (arrows) in the
Page 173 and 174:
al., 2003). We did not find such a
Page 175 and 176:
ANDERSEN, M., E. LIE, A. E. DEROCHE
Page 177 and 178:
LUROSS, J. M., M. ALAEE, D. B. SERG
Page 179 and 180:
organic mercury in liver and kidney
Page 181 and 182:
Introduction Polar bears (Ursus mar
Page 183 and 184:
Macroscopic examination of reproduc
Page 185 and 186:
Results and discussion The female p
Page 187 and 188:
SC II PC/LC Figure 2 The histology
Page 189 and 190:
The relatively low levels of analys
Page 191 and 192:
(Table 4), and we therefore conclud
Page 193 and 194:
Acknowledgements Danish Cooperation
Page 195 and 196:
Letcher RJ, Klasson-Wehler E, Bergm
Page 197 and 198:
Swart RL, Ross PS, Vedder LJ, Timme
Page 199 and 200:
10. Heier, A., C. Sonne, A. Gröne,
Page 201 and 202:
crine organs and skulls in the East
Page 203:
To investigate the relation between
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