Toxaphene in the aquatic environment of Greenland.

The octa- and nonachlorinated bornanes (toxaphene) CHBs 26, 40, 41, 44, 50 and 62 were analysed in Arctic char (Salvelinus alpinus), shorthorn sculpin (Myoxocephalus scorpius), ringed seal (Pusa hispida) and black guillemot eggs (Cepphus grylle) from Greenland. Despite their high trophic level, ringed seals had the lowest concentrations of these species, with a Σ6Toxaphene median concentration of 13-20 ng/g lipid weight (lw), suggesting metabolisation. The congener composition also suggests transformation of nona- to octachlorinated congeners. Black guillemot eggs had the highest concentrations (Σ6Toxaphene median concentration of 971 ng/g lw). Although concentrations were higher in East than in West Greenland differences were smaller than for other persistent organic pollutants. In a circumpolar context, toxaphene had the highest concentrations in the Canadian Arctic. Time trend analyses showed significant decreases for black guillemot eggs and juvenile ringed seals, with annual rates of -5 to -7% for Σ6Toxaphene. The decreases were generally steepest for CHBs 40, 41 and 44.

Comparing temporal trends of organochlorines in guillemot eggs and Baltic herring: advantages and disadvantage for selecting sentinel species for environmental monitoring.

Within Europe, the Marine Strategy Framework Directive (MSFD) is aimed at addressing the chemical status and quality of the marine environment. One of the main goals is to achieve Good Environmental Status (GES) in the marine environment. Environmental monitoring of biota e.g., Baltic herring and guillemot eggs, is conducted annually in Sweden to follow temporal changes in environmental contaminants. To determine the suitability of guillemot eggs as a sentinel species for investigating GES, we compared temporal trends of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) in these two species from single sampling sites within Sweden. Lipid content from guillemot eggs was consistently high and stable (yearly mean for >40 years, ∼12%) compared to that of herring (yearly mean for >20 years, ∼3%). A significant decreasing trend of ΣPCDD/F in TEQ WHO1998 was observed in guillemot eggs, but no trend was seen in herring. CB118 significantly decreased in both species, but in the last 10 years this decrease was not significant in herring. A number of advantages, such as high lipid content in the egg and a low coefficient of variation make guillemot suitable as a sentinel species. The advantages and disadvantages of using either guillemot eggs or Baltic herring are compared.