Selenium is an essential micronutrient for animals.
Concentrations of approximately 30 mg/kg dry weight are considered as background levels. The highest level found in the present survey was 25 mg/kg. The levels of selenium in Atlantic puffin and common guillemot were significantly higher than in other seabird species. Selenium is abundant in marine fishes and this may explain why selenium levels are higher in these two fish-eating seabird species.
No regional difference in selenium levels in different seabird species was found.