Elevated levels of polybrominated diphenyl ethers (PBDEs) in fish from Lake Mjøsa, Norway

Surprisingly high levels of PBDEs (polybrominated diphenyl ethers) in fish from Lake Mjøsa watercourse initialized a more detailed study of PBDE contamination in the Lake Mjøsa region as well as fish from other lakes in southeast Norway. With exception of the fish from Lake Mjøsa, the sum concentration of PBDEs in trout was, on a wet weight (ww) basis, in the range of 0.3–40 ng/g (21–1215 ng/g lipid weight (lw)) in fish fillet and 39–446 ng/g (125–915 ng/g lw) in burbot liver. The PBDE levels in fish from Lake Mjøsa, was found in the range of 72–1120 ng/g ww (2348–16,753 ng/g lw) in trout and 156–2265 ng/g ww (4201–45,144 ng/g lw) in burbot. It was later confirmed that the elevated levels in Lake Mjøsa were mainly caused by the release of PBDEs to the water from a textile manufacturer in the town of Lillehammer. In addition to PBDE levels in fish we also present information on the spatial distribution of PBDEs in air around the Mjøsa watercourse, based on the complementary use of passive air samples and analysis of moss, including data on measured air concentrations. The results confirm the presence of an active source of atmospheric PBDEs in the region of Lillehammer. Although this source appears to have a limited impact on atmospheric levels towards the southern reaches of the lake, it could still be a significant source of PBDEs to the lake as a whole. However, more research is needed to better understand and quantify the relative importance of various sources and pathways for which PBDEs enter Lake Mjøsa in order to support the development of future control strategies.