PARENT SESSION
18 - Endocrine Disruption
8:00 AM to 6:30 PM, Monday, 13 May 2002
Exhibition Area

(18-77) Effects of organochlorine pollutants on the thyroid hormone levels in glaucous gulls (Larus hyperboreus) from Bear Island, Norway.

Verreault, Jonathan^*,1, Gabrielsen, Geir¹, Skaare, Janneche^2,3, Jenssen, Bjørn⁴, ¹ Norwegian Polar Institute, The Polar Environment Center, Tromsø, Norway² The Norwegian School of Veterinary Science, Oslo, Norway³ National Veterinary Institute, Oslo, Norway⁴ Norwegian University of Science and Technology, Trondheim, Norway

ABSTRACT- Abnormal reproductive and thyroid hormone concentrations have been documented in number of wildlife species. Sublethal levels of organochlorine compounds can elicit a variety of adverse effects in development and reproduction of organisms. Instances of potential effects on the endocrinology of seabirds have been reported. However, endocrine disruption has not yet been documented in glaucous gulls. The aim of this study is to establish a relationship between thyroid hormone levels and organochlorine pollutant's toxicity in glaucous gulls (Larus Hyperboreus). Blood samples of 66 free-ranging birds of both sexes were collected in spring 2001 from Bear Island (Svalbard) during breeding period. Previous studies have reported high levels of POPs accumulation in wildlife at Svalbard. Plasma concentrations of 14 PCB congeners (PCB-31, 52, 101, 99, 118, 114, 153, 105, 138, 156, 157, 180, 170, 189) and 3 pesticides (HCB, oxychlordane, pp-DDE) were analysed, in addition to thyroid hormones (free and total thyroxin and triiodothyronine). Highlights of the results will be presented at the meeting.

Key words: endocrine disruption, organochlorine, glaucous gull