| Summary: | Polybrominated Diphenylethers (PBDEs) are widely used flame retarding products applied to e.g. electronic equipment and textiles with approximately 50,000 tonnes produced annually. Their chemical structures resemble chlorinated legacy POPs. As such their chemical half-lives, bioaccumulation potential and toxic mode of action are also similar. In 2006, Antarctic krill from across a 50c longitudinal range of the eastern Antarctic sector were analysed for a variety of legacy and emerging contaminants of concern including 16 PBDE congeners. Ten of twelve sampling stations between 40-90oE revealed low background levels of the dominant penta-BDE congeners PBDE-47 and - 99 in a similar range to those recently detected in the Arctic euphausiid species, Thyssanoessa inermis, sampled from the Svalbard archipelago. Notably however, several congeners were significantly elevated (x10-20) in krill sampled from sites at ~70oE. Elevated sampling sites were located in the vicinity of several active research stations, including; Davis (Australia), Mawson (Australia), Progress II (Russia) and Zhongshan (China). It is likely that active research stations in the Antarctic are contributing significantly to local PBDE contamination, serving to raise background levels resulting otherwise primarily from long range atmospheric transport. This hypothesis has recently been supported by Hale, et al. (2008, ES&T 42), who found high levels of PBDEs in indoor dust and wastewater sludge from McMurdo Station in the western Antarctic sector. Future work will seek to identify local sources among the research station cluster at ~70oE. Further, laboratory investigations will explore the uptake kinetics of PBDEs in Antarctic krill in order to shed new light on krill population structure and distribution.
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