title: Toxic and essential elements changed in black-legged kittiwakes (Rissa tridactyla) during their stay in an Arctic breeding area.
abstract: Seasonal fluctuations in mercury (Hg), cadmium (Cd), zinc (Zn), copper (Cu) and selenium (Se) concentrations were studied in black-legged kittiwakes (Rissa tridactyla) from Kongsfjorden, Svalbard (79°57'N, 12°12'E). Element concentrations were determined in muscle and liver tissue in kittiwakes collected in May, July and October 2007. Stable isotopes of carbon (δ(13)C) and nitrogen (δ(15)N) were analysed in muscle tissue to calculate trophic position (TP) and examine the possible influence of carbon source on element accumulation. Metallothionein (MT) concentrations in liver, as well as Hg and Cd concentration in size-fractionated liver supernatant were determined to evaluate the association between elements and MT. Mercury concentrations declined from May through July to October in both tissues, while concentrations of Cd were similar in May and July and lower in October. A decline in TP between May and July, indicating a shift from fish-based diet towards an invertebrate-based diet explains the declining Hg concentration. The low Hg and Cd concentrations in October may be a result of an increased elimination, probably related to moulting. Selenium decreased in the same manner as Hg in liver and muscle, possibly related to the formation of Se-Hg complexes. Zinc and Cu did not fluctuate in muscle tissue, whereas hepatic Zn concentrations where highest in May. Hepatic Zn concentrations were higher in females compared to males in May, possibly related to egg production. Hepatic MT concentrations were lower in October compared to July, following the same trend as Hg and Cd. Cadmium was predominantly bound to the MT fraction of proteins in liver tissue, whereas Hg was associated with the larger proteins, indicating that MT was not sequestering Hg in the kittiwakes.
authors.affiliation: Norwegian University of Science and Technology (NTNU), Department of Biology, N-7491 Trondheim, Norway. Electronic address: ida.beathe.overjordet@sintef.no.
authors.forename: Ida Beathe
authors.initials: IB
authors.lastname: Overjordet
authors.affiliation: Norwegian University of Science and Technology (NTNU), Department of Biology, N-7491 Trondheim, Norway.
authors.forename: Magnus Brunvoll
authors.initials: MB
authors.lastname: Kongsrud
authors.affiliation: Norwegian Polar Institute, N-9296 Tromsø, Norway.
authors.forename: Geir Wing
authors.initials: GW
authors.lastname: Gabrielsen
authors.affiliation: NTNU, Department of Chemistry, N-7491 Trondheim, Norway.
authors.forename: Torunn
authors.initials: T
authors.lastname: Berg
authors.affiliation: Norwegian Institute for Water Research (NIVA), N-0349 Oslo, Norway.
authors.forename: Anders
authors.initials: A
authors.lastname: Ruus
authors.affiliation: Akvaplan-niva, Fram Centre, N-9296 Tromsø, Norway; Faculty of Biosciences, Fisheries and Economics, UiT The Arctic University of Norway, Norway.
authors.forename: Anita
authors.initials: A
authors.lastname: Evenset
authors.affiliation: Norwegian Institute for Water Research (NIVA), N-0349 Oslo, Norway; Department of Biosciences, University of Oslo, Norway.
authors.forename: Katrine
authors.initials: K
authors.lastname: Borgå
authors.affiliation: Akvaplan-niva, Fram Centre, N-9296 Tromsø, Norway.
authors.forename: Guttorm
authors.initials: G
authors.lastname: Christensen
authors.affiliation: Norwegian University of Science and Technology (NTNU), Department of Biology, N-7491 Trondheim, Norway.
authors.forename: Bjørn Munro
authors.initials: BM
authors.lastname: Jenssen
mesh_terms: D000818:Animals; D002104:Cadmium / Q000378:metabolism; D046091:Charadriiformes / Q000378:metabolism*; D004784:Environmental Monitoring / Q000379:methods; D004785:Environmental Pollutants / Q000378:metabolism*; D005260:Female; D008099:Liver / Q000378:metabolism; D008297:Male; D008628:Mercury / Q000378:metabolism; D008668:Metallothionein / Q000378:metabolism; D009132:Muscles / Q000378:metabolism; D012643:Selenium / Q000378:metabolism; D013538:Svalbard; D014018:Tissue Distribution; D014131:Trace Elements / Q000378:metabolism*; D015032:Zinc / Q000378:metabolism
chemical_list: D004785:Environmental Pollutants; D014131:Trace Elements; D002104:Cadmium; D008668:Metallothionein; D008628:Mercury; D012643:Selenium; D015032:Zinc
keywords: Cadmium; Mercury; Metallothionein; Seabird; Selenium; Stable isotopes