Contaminants in Marine Mammals Greenland This dissertation – based on 30 selected English articles and book contributions – was accepted for public defense by the Faculty of Science, University of Copenhagen to acquire the doctor’s degree Contaminants in Marine in natural sciences. Seven thesis points is being addressed within three thematic topics; marine contaminant loads, health effects of contaminants and marine mammal migration and stock separations. The contaminant Mammals in Greenland part provides a review of key determining parameters (age, sex, season, food and climate), trends (geographic and temporal), bioaccumulation, biomagnifi cation and human exposure. The – with linkages to trophic levels, effects, diseases and distribution biological health effect section deals with observed effects of contaminants in top predators in the Arctic marine ecosystem as well as a discussion on mass mortality epizootics among Arctic and European mammals. Doctor’s dissertation (DSc), 2008 Finally, marine mammal distribution and stock separations are Rune Dietz discussed based on information from satellite telemetry, contami- nant studies as well as genetic, stable isotope and fatty acids pro- fi les. ISBN: 978-87-7073-037-2 OOmslag.inddmslag.indd 1 117-03-20087-03-2008 007:29:077:29:07 Denne afhandling er af Det Naturvidenskabelige Fakultet ved Københavns Universitet antaget til offentligt at forsvares for den naturvidenskabelige doktorgrad. København den 5. februar 2008. Nils O. Andersen, Dekan Aarhus Universitets Forskningsfond har finansieret trykningen af afhandlingen. This dissertation has been accepted by the Faculty of Science, University of Copenhagen for public defence for the Doctoral degree of Natural Science (DSc). Copenhagen 5 February 2008. Nils O. Andersen, Dean The University of Aarhus Research Foundation has funded the printing of the dissertation. Omslag.indd 2 15-04-2008 09:45:45 Contaminants in Marine Mammals in Greenland – with linkages to trophic levels, effects, diseases and distribution Doctor’s dissertation (DSc), 2008 Rune Dietz DDoctorsoctors ddissertation.inddissertation.indd 1 226-03-20086-03-2008 009:55:209:55:20 Denne afhandling er af det Naturvidenskabelige Fakultet, Københavns Universitet antaget til offentligt forsvar for den naturvidenskabelige doktorgrad ved August Krogh Bygningen, Biologisk Institut den 9. maj 2008, kl. 13.00-18.00. This dissertation has been accepted by the Faculty of Science, University of Copenhagen for public defense for the Natural Scientifi c Doctoral degree (DSc) at the August Krogh Building, Biological Institute, 9 May 2008 from 13.00 to 18.00. DDoctorsoctors ddissertation.inddissertation.indd 2 226-03-20086-03-2008 009:55:259:55:25 DDoctorsoctors ddissertation.inddissertation.indd 3 226-03-20086-03-2008 009:55:309:55:30 Data sheet Title: Contaminants in Marine Mammals in Greenland – with linkages to trophic levels, effects, diseases and distribution Subtitle: Doctor’s dissertation (DSc) Author: Rune Dietz Department: Department of Arctic Environment Publisher: National Environmental Research Institute University of Aarhus – Denmark URL: http://www.neri.dk Year of publication: April 2008 Editing completed: 2008 Financial support: The Carlsberg Foundation Please cite as: Dietz, R. 2008: Contaminants in Marine Mammals in Greenland – with linkages to trophic levels, effects, diseases and distribution. Doctor’s dissertation (DSc). National Environmental Research Institute, University of Aarhus, Denmark. 120 pp + 30 articles. Keywords: Marine mammals, contaminants, heavy metals, organohalogenated compounds, effects, distribution, stock separations, satellite telemetry, Greenland. Layout/illustrations: Tinna Christensen & Kathe Møgelvang Cover photo: Rune Dietz ISBN: 978-87-7073-037-2 Printed by: Schultz Grafi sk, Denmark Environmental certifi ed after EMAS, ISO 14001 and FSC Circulation: 300 Number of pages: 120 Internet version: The report is also available in electronic format (pdf) at NERI’s website http://www.dmu.dk/Pub/Doctor_RDI.pdf Supplementary note: This dissertation has been accepted by the Faculty of Science, University of Copenhagen for public defense for the Natural Scientifi c Doctoral degree (DSc) at the August Krogh Building, Biological Institute, 9 May 2008 from 13.00 to 18.00. DDoctorsoctors ddissertation.inddissertation.indd 4 226-03-20086-03-2008 009:55:399:55:39 Contents Summary / Sammenfatning 7 List of papers 13 1 Introduction 17 Setting the stage 18 Contaminants included in the dissertation 19 Historic overview 21 Thesis of the dissertation 24 Structure of the dissertation 25 2 Results and discussion 27 Marine contaminant loads 28 Contaminant related pathological effects and diseases 59 Marine mammal migration and stock separations 73 3 Conclusions 85 4 Recommendations for future investigations 91 5 Acknowledgements 95 6 References 99 7 Appendices 117 Thesis articles – included on CD DDoctorsoctors ddissertation.inddissertation.indd 5 226-03-20086-03-2008 009:55:399:55:39 Photo: R. Dietz DDoctorsoctors ddissertation.inddissertation.indd 6 226-03-20086-03-2008 009:55:399:55:39 Summary/ sammenfatning etz DDoctorsoctors ddissertation.inddissertation.indd 7 226-03-20086-03-2008 009:55:419:55:41 Summary The present dissertation provides a review of effects. The Arctic has become an important key determining parameters (age, sex, season, place to study contaminants, well suited for food and climate), trends (geographic and the study of chemical persistence, bioaccu- temporal), bioaccumulation, human exposure mulating and biomagnifi cating properties, and effects of contaminants in top predators long-range transport and adverse effects that in the Greenland marine ecosystem. Further- are important criteria identifi ed under inter- more, the dissertation links the contaminant national agreements and Conventions aimed issue to marine mammal distribution and at regulating OHCs or persistent organic pol- stock separations monitored mainly by satel- lutants (POPs). lite telemetry. The review and conclusions are based on 30 key publications as well as The focus area selected supporting literature. Some of the highest human exposure levels to persistent toxic contaminants are found in the Setting the stage Arctic. This is due to the long-range transport The Arctic has previously been regarded a of contaminants to the region, long marine pristine environment. It is a region with lim- food chains that include slow-growing spe- ited industry, almost no agriculture and only cies, and the fact that marine mammal preda- a few local areas where some organohalogen- tors at the top of these food-chains constitute ated compounds (OHCs) have been used for an important part of the Inuit consumer’s pest control. However, during the 1970s and food intake. In addition, the focus on the 80s it became evident that contaminants such Greenland ecosystem is of major importance as heavy metals and OHCs were present in as the Greenland Inuit population were found signifi cant concentrations in the higher trop- to have the highest exposures of any people hic levels of marine ecosystems and in Inuit in the Arctic when it comes to Hg, PCB, DDE, populations that use them for food. Since oxychlordane and toxaphene. Diets including then, a substantial effort has been addressed marine mammals were identifi ed as the ma- to resolve the contaminant questions relating jor source of the contaminant exposure to the to origins, transport, geographical and tem- Greenlanders and other Arctic populations. poral trends as well as toxicity and biological Therefore, the marine environment, and in particular species at the higher trophic levels, such as certain marine mam- mals, including polar bears, became a focus of my work over the past years, and therefore also the subject of this disserta- tion. Data are also pre- sented for lower trophic levels that were part of the screening of the entire eco- system and provide infor- mation that explains where the exposures are the highest. Photo 1. Marine mammals, including polar bears are the focus of this disserta- tion due to their hight loads of contaminants and hence their chance for display- ing effect due to their high trophic position and their high regional exposure. Photo: R. Dietz. 8 Contaminants in Marine Mammals in Greenland DDoctorsoctors ddissertation.inddissertation.indd 8 226-03-20086-03-2008 009:55:429:55:42 Structure of the dissertation high levels are most likely to occur, and where This dissertation addresses three main topics: the lowest exposed animals for use as refer- 1) Marine contaminant loads, 2) Contaminants ence groups may be found. related pathological effects and diseases, and (iv) Temporal trends in contaminant loads 3) Marine mammal migration and stock sepa- are detectable in key species in the Greenland rations. ecosystem. Long-term studies in appropriate media reveal increases of Hg with a substan- tial anthropogenic contribution. These in- Conclusions creases appear to be continuing in Northwest Greenland and the Central Canadian Arctic. The main conclusions are: Mercury levels east of Greenland and levels (i) Basic parameters such as age and sex of the of “legacy OHCs”, such as PCBs, DDTs, animal, tissue type, season of collection, af- HCHs, HCB, chlordanes, dieldrin, and copla- fect contaminant loads. It was documented nar PCBs are showing declines. Time series that older animals tend to have higher con- on toxaphene, PCDDs and PCDFs are more centrations of Hg and Cd and for some OHC uncertain, but may be decreasing. Increases