PH11 Bioaccumulation and Biotransformation of POPs
Exhibit Hall
8:00 AM - Thursday, 13 November 2003
(PH099) Polybrominated Diphenyl Ether Metabolism and Hydroxylated-PBDEs in Common Carp (Cyprinus carpio) From the Detroit River.
Letcher, R.1, D'Sa, I.2, Drouillard, K.1, Valters, K.1, Alaee, M.2, 1 Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON, Canada2 Aquatic Ecosystem Protection Research Branch, National Water Research Institute, Environment Canada, Burlington, ON, Canada
ABSTRACT- Polybrominated diphenyl ethers (PBDEs) are a class of brominated flame retardants (BFRs) that are of increasing environmental concern in the Great Lakes system. In fish for example, over approximately the last 10 years PBDE levels have been increasing exponentially in Great Lakes lake trout (Salvelinus namaycush) muscle. One of the major PBDE congeners in the tissues of aquatic species, especially in fish such as common carp (Cyprinus carpio) from the Detroit River, is 2,2',4,4'-tetrabromo diphenyl ether (BDE-47). We recently reported HO-PCBs and other halogenated phenolic compounds (HPCs) in the blood-plasma of 13 pelagic- and benthic-feeding fish from the Detroit River. However, knowledge of the uptake, elimination and especially metabolism of PBDEs in fish is limited. In the present study, we determined the congener patterns and relative amounts of PBDEs, hydroxylated (HO) PBDEs and methoxylated (MeO) PBDEs in the blood-plasma of common carp from the Trenton Channel-Gross Ile area of the Detroit River. The concentration of BDE-47 is 1.8 ng/g (wet weight) in the carp plasma. MeO-PBDEs are not detectable in the neutral fraction. However, a very dominant HO-PBDE was found in the HPC fraction, i.e., 6-HO-BDE47 at a concentration of 42.3 pg/g (w.w.) and was 2.3% of the BDE-47 concentration. Analysis of the plasma of 11 other Detroit River fish species also contained the predominant 6-HO-BDE-47. In vitro metabolism studies with liver microsomes from Detroit River carp were also revealing in the potential of carp to metabolize BDE-47 to HO-PBDEs. These results indicate that circulating and bioavailable HO-PBDEs may be a potential health concern carp and other PBDE-exposed fish in the Detroit River.
Key words: Hydroxylated-PBDEs, PBDEs, Common carp, Detroit River