ENPO2491 Diskused No.pages14,DTD=4.3.1 Version 7.51e ARTICLE IN PRESS UNCORRECTED PROOF Levels and patterns of persistent organochlorines in minke whale(Balaenopteraacutorostrata)stocksfromtheNorth Atlantic and European Arctic K.E. Hobbs a ,D.C.G.Muir a, *,E.W.Born b ,R.Dietz c ,T.Haug d , T. Metcalfe e ,C.Metcalfe e ,N.Øien f a NationalWaterResearchInstitute,EnvironmentCanada,Burlington,ON,CanadaL7R4A6 b GreenlandInstituteofNaturalResources,POBox570,DK-3900Nuuk,Greenland c DepartmentofArcticEnvironment,NationalEnvironmentalResearchInstitute,Frederiksborgvej399,POBox358,DK-Roskilde,Denmark d NorwegianInstituteofFisheriesandAquaculture,N-9291Tromsø,Norway e EnvironmentalResourcesStudies,TrentUniversity,Peterborough,ON,CanadaK9J7B8 f InstituteofMarineResearch,POBox1870,N-5817Bergen,Norway Received 7 May 2001; accepted 16 April 2002 The authors would like to dedicate this paper to the memory of Dr. Stuart Innes who died in a tragic accident while conducting marine mammal research in the Canadian arctic in May 2000. His work using organochlorine patterns to identify stocks of beluga inspired this study. ‘‘Capsule’’: MinkewhalesappeartobequitemobileandhavemultiplefeedingareasintheNEAtlanticOcean. Abstract Regional variation in PCBs and organochlorine (OC) pesticide concentrations was examined using the blubber of 155 minke whales (Balaenoptera acutorostrata) sampled in seven regions in the North Atlantic and European Arctic, including western and southeastern Greenland, the Norwegian Sea, the North Sea and the Barents Sea. The levels and relative proportions of OCs were also used to examine the boundaries for North Atlantic minke whale stocks previously defined by the International Whaling Commission (IWC). Concentrations of major OC groups (ÆPCB, 89.1–22 800 ng/g lipid; ÆDDT, 65.3–6280 ng/g lipid; ÆCHL, 33.3–2110 ng/g lipid) generally increased from west to east, while HCH concentrations (ÆHCH, < 1–497 ng/g lipid) showed the oppositetrend.Statisticalcomparisonbetweensixregionsusingsex-adjustedleastsquaredmeanconcentrationsshowedthatminke whalesfromtheBarentsSeahadsignificantlyhigherconcentrationsof ÆPCBsthanthosefromtheVestfjorden/Lofoten,theNorth Sea,andwestSvalbard,aswellassignificantlyhigher ÆDDTconcentrationscomparedtowestGreenlandanimals.Thedifferences in concentrations suggest that west and southeast Greenland minkes may represent one group of whales, which are distinct from boththeJanMayenminkesandthosefromotherIWCdefinedstocksinnorthernEuropeanwaters.Principalcomponentsanalysis using proportions of 71 PCB congeners and 20 OC pesticides (of total OCs) did not reveal any major differences among groups although minkes from the North Sea were distinguished from those from Greenland waters by higher loadings of more highly chlorinated PCBs and recalcitrant OC pesticides. The general similarity in mean levels of ÆPCBs, ÆDDT and ÆCHL, as well as mean principal components analysis scores, among minkes sampled at Jan Mayen, Svalbard, Vestfjorden/Lofoten, the North Sea andtheBarentsSeasuggeststhatthewhalesarequitemobileandmayfeedinmultipleareaswithinthenortheasternAtlantic. Keywords: NorthAtlantic;Minkewhales;PCBs;Organochlorinepesticides;Stockdelineation 1. Introduction Minke whales (Balaenopteraacutorostrata) are found throughout the North Atlantic from the east coast of Canada to the North Sea, Svalbard and as far east as theNovayaZemlyaregionofthewesternRussianarctic duringthesummer.Althoughthedistributionofminkes is relatively continuous across this range, the Interna- tional Whaling Commission (IWC) has defined four management units for the North Atlantic minke whales (Canadian East Coast, West Greenland, Central and Northeastern) because of the apparent occurrence of 0269-7491/02/$ - see front matter # 2002 Published by Elsevier Science Ltd. PII:S0269-7491(02)00218-X Environmental Pollution & (&&&&) &–& www.elsevier.com/locate/envpol 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 * Corresponding author. Tel.: +1-905-319-6921; fax: +1-905-336- 6430. E-mailaddress: derek.muir@cciw.ca (D.C.G. Muir).