Bromerade flamskyddsmedel (PBDE) i fisk och sediment – en litteraturstudie och en fallstudie av tio svenska referenssjöar

Abstract: Flame retardants are used in plastics, fabrics, furnishing foam and electronics to reduce their fire hazards. The kind of brominated flame retardants presented in this study are the PBDEs, polybrominated diphenyl ethers. Because their molecular structures are similar to PCBs, there is a fear that these substances are environmental hazards as the PCBs, by decreasing the thyroid hormone levels. Lower brominated PBDEs are found to cause deterioration of memory capacity, learning capability, and motoric behaviour. There is a discussion going on whether the higher brominated PBDEs have the same effect. During the last decades the level of PBDEs in the environment has increased. Two cases that have drawn much attention to the PBDEs are the discoveries of PBDEs in eggs of peregrine falcon (Falco peregrinus) and in breast milk in Swedish women. The aim of this study is to investigate the background levels of PBDEs in Swedish reference lakes and to compare them with other areas with or without direct local influence. The study consists of two parts. The first part is a literature study about PBDEs in biota and sediments in different parts of the world. The literature study shows that, in all countries, sediment and biota samples taken from industrial areas and sewage sludge have high levels of PBDEs due to direct local influence from e.g. foam manufacturing industries or textile industries. Biota and sediment samples far from direct local industrial effluents have low levels of PBDEs, if detectable at all. The second part of this study presents the results of a screening study of PBDEs in perch (Perca fluviatilis) and sediments from ten Swedish reference lakes. Only three perches out of 79 investigated from the reference lakes contained PBDEs above the detection level, 1 ng/g dw, and all these samples where just above the detection level. The other 76 perches and all the sediment samples had PBDE levels under the detection limit. The levels of PBDEs in this study are in accordance with screening studies of non-point source locations in other countries.