Retrospective monitoring of perfluorinated compounds in archived herring gull eggs

Although perfluorinated compounds (PFCs) were used for many applications since the 1950s only in recent years their environmental relevance became apparent. Meanwhile the persistent, bioaccumulative and toxic potential of several PFCs has been proven. A retrospective monitoring was performed to assess concentration trends of PFCs in marine biota from the German Environmental Specimen Bank (ESB). Archived homogenate samples of herring gull (Larus argentatus) eggs covering the period 1988-2008 (North Sea; islands Trischen and Mellum) and 1991-2008 (Baltic Sea; island Heuwiese) were analyzed for a set of PFCs. Compounds detected with highest levels were perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA). North Sea eggs had higher PFOS concentrations than Baltic Sea eggs in most years. While the PFOS time series for Baltic Sea eggs showed an increasing trend, North Sea eggs revealed varying concentrations. Eggs from Heuwiese, located in a Baltic Sea region with negligible anthropogenic impacts, showed lower PFOA levels (in the range of the limit of quantification of 0.5 ng/g wet weight) than North Sea eggs. However, especially in some years quite high PFOA levels were found in gull eggs from the North Sea sites.