title: Tetra- and tribromophenoxyanisoles in marine samples from Oceania.
abstract: Some methoxylated polybrominated diphenyl ethers (MeO-BDEs) are known halogenated natural products (HNPs) and are frequently detected in higher organisms of the marine environment. In this study we demonstrate that a prominent MeO-BDE, previously detected in marine mammals from Australia, is identical to 3,5-dibromo-2-(2',4'dibromo)phenoxyanisole (BC-3, 6-MeO-BDE 47). Up to 1.9 mg/ kg of 6-MeO-BDE 47 was present in cetaceans from Australia, 0.2-0.3 mg/kg in two crocodile eggs from Australia, but concentrations of 1 or 2 orders of magnitude lower were found in shark liver oil from NewZealand and in marine mammals from Africa and the Antarctic. Concentrations of 6-MeO-BDE 47 in samples from Australia were in the same range as anthropogenic pollutants such as PCB 153 and p,p'-DDE. Along with 6-MeO-BDE 47 and the known HNP 4,6-dibromo-2-(2',4'-dibromo)phenoxyanisole (BC-2, 2'-MeO-BDE 68), several tribromophenoxyanisoles (MeO-triBDE) were present in tissue of Australian cetaceans. To determine their structure, abiotic debromination experiments were performed using 6-MeO-BDE 47 and 2'-MeO-BDE 68 and superreduced dicyanocobalamine. These experiments resulted in formation of eight MeO-triBDEs, all of which were detected in the cetacean samples. Five of these eight MeO-triBDEs could be identified based on two standard compounds as well as gas chromatographic and mass spectrometric features. It was also shown that the first eluting isomer (compound 1), 6-MeO-BDE 17 (compound 2), and 2-MeO-BDE 39 (compound 5) were the most prominent MeO-triBDEs in the Australian cetacean samples. The concentrations of the MeO-triBDEs in two cetacean samples were 0.20 and 0.36 mg/kg, respectively. Although the reductive debromination with dicyanocobalamine resulted in a different congener pattern than was found in the marine mammals, it could not be excluded that the tribromo
authors.affiliation: Institute of Food Chemistry, University of Hohenheim, Garbenstrasse 28, D-70599 Stuttgart, Germany.
authors.forename: Joachim
authors.initials: J
authors.lastname: Melcher
authors.forename: Daniel
authors.initials: D
authors.lastname: Olbrich
authors.forename: Göran
authors.initials: G
authors.lastname: Marsh
authors.forename: Vladimir
authors.initials: V
authors.lastname: Nikiforov
authors.forename: Caroline
authors.initials: C
authors.lastname: Gaus
authors.forename: Simon
authors.initials: S
authors.lastname: Gaul
authors.forename: Walter
authors.initials: W
authors.lastname: Vetter
mesh_terms: D000489:Alligators and Crocodiles / Q000378:metabolism; D000818:Animals; D000840:Anisoles / Q000032:analysis* / Q000737:chemistry; D002591:Cetacea / Q000378:metabolism*; D002850:Chromatography, Gel; D004784:Environmental Monitoring / Q000706:statistics & numerical data*; D008401:Gas Chromatography-Mass Spectrometry; D008099:Liver / Q000737:chemistry*; D044349:Oceania; D010063:Ovum / Q000737:chemistry; D010647:Phenyl Ethers / Q000032:analysis* / Q000737:chemistry; D012754:Sharks / Q000378:metabolism; D014805:Vitamin B 12
chemical_list: C496823:2-(2',4'-dibromophenoxy)-3,5-dibromoanisole; C496824:2-(2',4'-dibromophenoxy)-4,6-dibromoanisole; D000840:Anisoles; D010647:Phenyl Ethers; D014805:Vitamin B 12