Temporal variation in circulating concentrations of organochlorine pollutants in a pelagic seabird breeding in the high arctic

International audienceThe present study explored short-term temporal variations in circulating concentrations of 3 legacy organochlorines withdifferent physicochemical properties (polychlorinated biphenyl 153 [PCB-153], p,p0-dichlorodiphenyldichloroethylene [DDE], andhexachlorobenzene [HCB]) in breeding kittiwakes (Rissa tridactyla) in a colony in Svalbard (788N), Norwegian Arctic. Concentrationswere measured in blood of a large number (n¼412–521 blood samples, depending on the data analyses) of prebreeding, incubating, andchick-rearing birds over a period of 5 yr (2007–2011). The PCB-153 concentrations were equal in male and female blood in theprebreeding period, whereas females had significantly lower concentrations during incubation and chick rearing, probably because oftheir ability to eliminate organochlorines through egg laying. A similar temporal pattern was observed with DDE, although the lowerconcentrations in incubating females were not significant. Males and females had similar concentrations of HCB over all reproductivestages. The concentrations of all 3 compounds varied greatly between years. The concentrations of PCB-153 tended to decline over thestudy period, whereas concentrations of HCB showed an increasing trend, especially among chick-rearing males late in the season.Concentrations of PCB-153 increased approximately 2.5 times from the prebreeding to the chick-rearing period, concurrent withmobilization of body lipids (reduced body mass).Asimilar, but less pronounced trend was found for HCB. For DDE, however, kittiwakeshad the highest concentrations in the prebreeding period, suggesting relatively high exposure in their winter areas. The present studydocumented large variations in circulating concentrations of legacy organochlorines among and within breeding seasons in kittiwakes,but the alterations within seasons were relatively consistent from year to year