Polar bears and human health - Arctic Research Centre - Aarhus ...

STUDIES ON WILDLIFE VS HUMANSAdvantages• Wildlife represents the food exposure to humans• Easy acces to samples from hunters• Many species and larger populations to study• Broader ranges in contaminant loads• Limited interference with lifestyle changes• Limited Ethical problems• Historic collections may be more extensive• Processes are closer to biological and physicalprocesses• Disadvantages• Unknown history• Uncertainties on age and exposure• No public information registration files

MAIN POLAR BEAR PROBLEMS?SmokingLess suitabledenning areasSociallifesyleHuntMurderChange infeedingpatternsStarvationCannibalism

INUIT CONSUMPTION AND FOOD GUIDELINESDietz et al. 1996, Dietz 2008Dietz et al. 1996; Dietz 2008

POLAR BEARS AS WHISTLE BLOWERSContaminantsPrecipitationTemperatureStarvationSea iceImmunityBMDBraindamageReproductionEffectStudiese.g.:HistopathologyInfections

Hg (ppm dw)HG TIME TRENDS IN POLAR BEAR HAIR302520NWG Medians 1892-2008EG Medians 1892-2008Svalbard MediansLancaster SoundWestern Hudson BayExpon. (NWG Medians 1892-2008)Expon. (EG Medians 1892-2008)Expon. (Lancaster Sound)Expon. (Western Hudson Bay)1510501890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010YearDietz et al. 2006; 2011

Historic proportion of presentHISTORIC HG TIME-SERIES IN ARCTIC WILDLIFE AND HUMANS1008060Beluga teethGyrfalcon featherHuman teethPerigrine falcon featherPolar bear hairRinged seal teethMan-madecontributionca. 94%4020Baseline ca. 6%01200 1300 1400 1500 1600 1700 1800 1900 2000YearDietz et al. 2009

PCB lw10000 30000 50000PBDE lw50 100 150 200 250PFOS ng/g wwDDT lw0 500 1000 15001500 2000lw0 1000 2000 3000 4000PCB lw10000 30000 50000PBDE lw20 40 60 80 100POLAR BEARS PROVIDE SOME OF THE BESTUNBIASED TIME SERIESPolar bear, Juvenile, IttoqqortoormiitPolar bear, 5 years old, Ittoqqortoo1985 1990 1995 2000 2005 20101985 19901985 1990 1995 20001995 2000 200520YearYearDietz et al. 2012a; 2012bYear

PCB lwDDT lw10000 30000 500000 500 1000 15000 100 200 3005 10 15 20 25 30 35Emission t/yEmission kt/yPBDE-47 lw0 20 40 60 80 10020 40 60 80 100BDE-47 Emission t/yDOES THE OBSERVED CONCENTRATIONSPolar bear, Juvenile, IttoqqortoormiitREFLECT CLIMATE TRENDS?Breivik et al. 2002Polar bear, Juvenile, IttoqqortoormiitPolar bear, Juvenile, Ittoqqortoormiit1960 1970 1980 1990 2000 2010YearAlcock et al. 2003Li et al. 20031960 1970 1980 1990 2000 2010Year1980 1985 1990 1995 2000 2005 2010Year

1.10 1.20PCB lw10000 30000 50000ΣPCB, BF AND SI IN EAST GREENLAND POLAR BEARS1.10 1.20PCB lw10000 30000 500001.15 1.25PCB lw5000 15000 25000Polar bear, Juvenile, IttoqqortoormiitPolar bear, Adult female, IttoqqortoormiitPolar bear, Adult male, Ittoqqortoormiit1985 1990 1995 2000 2005 2010YearBiomagnification factor PB/RS1985 1990 1995 2000 2005 2010Year1985 1990 1995 2000 2005 2010YearSI (N15) ratio PB/RSN15, juvenileN15, adult femaleN15, adult male1985 1995 20051985 1995 20051985 1995 Dietz et 2005 al. 2012a

Percentage of dietPOLAR BEAR FOOD VARIATION OVER TIMEPolar bear Diet100.090.0Bearded.seal Harp.seal Hooded.sealNarwhal Ringed.seal WalrusLinear (Harp.seal) Linear (Hooded.seal) Linear (Ringed.seal)80.070.060.050.040.030.020.010.00.01982 1987 1992 Year 1997 2002 2007McKinney et al. in press

BMD (g/cm2)Penile Length (mm)WHISTLE BLOWING: EFFECTS1.0 1.5 2.0 2.5 3.01900 1920 1940 1960 1980 2000OSTEOPORSIS?REDUCED SIZE OFSEXUAL ORGANS?Sonne et al. 2004, 2006, 2013Year907050300 1000 2000 3000Chlordane concentration (ng/g lw)

WHISTLE BLOWING: EFFECTSC-cell proliferation Calcitonin Nodular hyperplasiaPPHE 50x. Bar= 100µm Calcitonin 100x. Bar= 60µm HE 40/100x. Bar= 60µmInterstitial fibrosisSonne et al. 2011MT 200x. Bar= 30µm

NMDA-GlutamateReceptor Levels (fmol/mg)30002500200015001000BrainstemETHICSIN SCIENCE50000.1 0.3 1Brain Stem THg (µg/g)2.521.510.50

RQ Immune systemRISK QUOTINTS FOR EFFECT ON THE IMMUNE SYSTEMIN JUVENILE EAST GREENLAND POLAR BEARS100001000100101AllPCBHCHPFOSHG liverOxychlordanHG-hairDDTDieldrinHCBPBDE0.10.011980 1985 1990 1995 2000 2005 2010YearRisk Quotients (RQ=BR/CBR) based on conservative data for critical oral dose of ratsData from Dietz et al. in prep

PFSA (ng/ml)PERSPECTIVES IN COMBINING DATA FROMHUMANS AND WILDLIFE350300250QaanaaqNuukTasiilaqFaroe Island Children (5y)Faroe Island mothersJuvenile polar bears EGAdult polar bears EG--------Polar bear--------254318200150100------------------------------------Humans----------------------------------635001233Long et al. 201117132------Immune effects------Grandjean et al 2012Dietz et al. in prep

DOSE RESPONSE ASSAYS ON LYMPHOCYTESDietz et al. 2012aLevin et al. in prep

PERSPECTIVES IN COMBINING DATA FROMHUMANS AND WILDLIFEHerpesvirusCoxiellaburnetiiInfluenzaA & BHepatitisABrucellasppMycobacteriumtuberculosisMorbillivirusVibreocholersSalmonellatyphimurionCalicivirusDermatophiluscongulensisEncephalitisLeptospirainterroganskircheriStaphylococcusaureusPapillomaRabies

CHALLENGES IN COMBINING DATA FROMHUMANS AND WILDLIFEHH AND WILDLIFE AMAP EFFECT ASSESSMENT:• Comparative effectassessment• Pharmacokineticmodelling• Dose response approachon immunosupression• Zoonotic diseases• Endocrine system• Cardio-vasculardiseases• Diabetes• Cancer• Osteoporosis• Other diseases