Svalbard: projects/activities

Arctic animals utilize periods with high food availability for feeding and lipid deposition, whereas they rely on stored lipids during unfavorable periods. Hence, many arctic inhabitants exhibit profound seasonal cycles of fattening and emaciation. In the Arctic, feeding is associated with fat deposition and contaminant accumulation. When lipids are mobilized, accumulated contaminants are released into the circulation. Consequently, blood contaminant concentrations may increase markedly and result in a redistribution of the contaminant(s) from “insensitive”, adipose tissues to sensitive organs, and increased contaminant bioavailability. Such variations complicate interpretations of pollutant toxicity, both in effect studies and in monitoring programs, and remains an important future reseach area. In the present study, we will use arctic fox (Alopex lagopus) as a model species for investigating tissue distribution and bioavailability of organochlorine contaminants (OCs) in relation to natural variations in lipid status (field study). These data will be supplemented and validated through a contamination study with blue fox (A. lagopus), where the seasonal changes in lipid status of wild fox are simulated in the laboratory. In both the field and laboratory study, possible effects of OCs on steroid hormone synthesis, and plasma levels of hormones, vitamin E and retinol will also be assessed.

The present project includes one pilot study of wild adult glaucous gull (Larus hyperboreus) and one experimental study of glaucous gull chicks raised in captivity. The pilot study of adult gulls gave us enough blood and tissue samples to develop the methods needed for immune system analysis in the laboratory experiment. In the experimental study a total of 39 glaucous gull chicks were hatched and raised in captivity in Svalbard, Norway. The chicks were divided into two groups. One experimental group (20 chicks) was given food that mimicked the “natural” food found in the marine environment. The control group (19 chicks) was given “clean” food. After 56 days the chicks were sacrificed in order to collect samples for analyses of organochlorines (OCs) and immunocompetence measurements. The experimental group had 2.8, 3.9, 5.0, and 6.1 time’s higher concentrations of HCB, Oxychlordane, ?DDT, and ?PCB, respectively, compared to the control group at day 56. All chicks used in the experiment were immunised with various vaccines and sera in order to test their ability to respond against foreign antigens. The experimental chicks produced low levels of virus neutralising antibodies when tested against the herpes virus and reovirus. They produced higher levels of neutralising antibodies when tested to tetanus toxoid. There was, however, no difference between the experimental groups with regard to the mean antibody titres. The chicks in both groups also responded to the influenza virus by increasing the production of specific antibodies. However, the mean antibody titre in the exposed group was significantly lower than in the control group. The mitogen-induced response of blood lymphocytes to PHA and LPS was significantly higher in the exposed group compared to the control group. The specific response of blood lymphocytes to Con A, PWM, KLH, TET, and PPD was higher in the exposed group compared to the control group. However, do to high variance in the exposed group there was no significant difference between groups with regard to the lymphocyte response to these mitogens. The results from the present study indicate a toxic effect of OCs on the glaucous gull chicks, which induced a systematic activation of the immune system. Further work on data will be performed.

Due to the high organochlorine concentrations reported in Arctic top predators, and the potential transport of contaminants with the drifting sea-ice in the Arctic, organisms constituting lower trophic levels living in association with sea-ice have been proposed as susceptible of uptake of high loads of organic pollutants. The present project studies the organochlorine occurrence in organisms living in the marginal ice zone north of Svalbard and in the Fram Strait. This includes both ice fauna (ice-amphipods), zooplankton, polar cod and different seabird species foraging in the marginal ice zone. Our objectives are to investigate: *The bioaccumulation of organochlorines in ice-associated amphipods in relation to diet preference, spatial variation due to sea ice drift route, size, sampling year, uptake and distribution within the body. *Comparison of organochlorine contamination in pelagic and ice-associated organisms at the similar trophic position, to investigate the effect of sea ice as a transporter and concentrator of pollutants. *Spatial variation in zooplankton species, related to differences in water masses and exposure to first year or multi year sea ice. *The contamination load in different seabirds feeding in the marginal ice zone, in relation to diet choice and estimated trophic position, taxonomically closeness and the induction of hepatic CYP P450 enzymes.

The study covers many areas of ecotoxicology research on polar bears. Monitoring of POP levels and studies of effects on endocrine disruption, immune system, reproduction, and demography are all parts of the study.

Surface samples collected around Svalbard in 1997 have been analysed for total content of heavy metals, Polycyclic Aromatic Hydrocarbons (PAHs), Polychlorinated Biphenyls (PCBs) and a selection of pesticides. Sample localities have been selected to include areas not covered by previous investigations. Based on the data set and results from previous expeditions in the area, contamination levels as well as potential sources for the pollutants are discussed. The PAH levels for most stations are moderately elevated with a high contribution of aromatic hydrocarbons associated with petrogenic sources. Hence the dominant sources for the PAHs is most likely derived from petroleum seepage and or coal mining. Long-range transport of aromatics associated with anthropogenic input is a minor component of the observed PAH levels. The highest concentration of PAH is found in Storfjorden with a value higher than the elevated concentrations earlier reported from the south-eastern Storfjorden and over the Central Bank. The concentration levels of the metals arsenic, lead, chromium and nickel were moderately elevated. Because of sparse information on the natural geomorphology, background metal concentrations are not known for this area. Hence, no quantitative comparison of natural and anthropogenic inputs for metals can be made. However, the most dominant source is assumed to be natural and related to the geological conditions in the area. All PCB levels were low, suggesting a dominant influence of long-range transport of these compounds to the area. Pesticide data showed low contamination of all compounds and suggests a predominant long-range atmospheric source for these pollutants.