Bioconcentration of Polybrominated Diphenyl Ethers PBDEs

In 1981, the presence of PBDEs in fish Esox Indus) from Swedish rivers was first reported by Anderson and Blomkvist [264]. The highest PBDE concentra- 

From their high n-octanol/water partition coefficient (K, ) (see Table 15) it can be assumed that PBDEs could be bio concentrated to a high extent in fish and other aquatic organisms. Recently the analysis, environmental fate, toxicokinetics, biotransformation, bio accumulation, toxicity, and environmental occurrence was reviewed by Pijnenburg et al. [249]. In the following part the bioconcentration of PBDEs in aquatic organisms, especially fish, is critically reviewed. Some information on endocrine disrupting properties of PBDEs is also presented. 

There is only little information available on bioconcentration using PBDEs in fish and other aquatic organisms. In 1982 the Chemicals Inspection and Testing Institute in Tokyo, Japan, investigated the bio concentration of pentabromobi-phenyl ether in carp [259,293]. The fish were exposed for 8 weeks to commercial pentabromobiphenyl ether at a concentration of 10 and 100 pg 1 The bioconcentration factors (on a wet wt. basis) were more than 10,000. However, it is clear that for such super-hydrophobic chemicals with log values of 6.64 - 6.97 no steady-state is reached after 8 weeks. The second reason that this BCF value was underestimated is that the test chemicals concentration in the water was ca. four to five orders of magnitude higher than the water solubility. The water solubility of pentabromobiphenyl ether (PBDE) is 9 X 10 mg 1 = 0.9 ng 1-1 at20°C [259]. 

From the high production volume and apphcation, environmental persistence, and their high n-octanol/water partition coefficients (K, ) it can be concluded that the higher brominated diphenyl ethers are bio concentrated to a high amount in algae, mussels, fish, and other aquatic organisms. The PBDEs may be considered to be a potential threat for aquatic mammals and human health, especially through fish consumption. 

Recently it was shown by Darnerud and Sinjari [286a] that 2,2, 4,4 -tetrabro-modiphenyl ether decreased the total thyroxine plasma levels in rats and mice 

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