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- Unger, Maria, 1980-, et al.
(författare)
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Characaterization of an abundant and novel methyl- and methoxy-substituted brominated diphenyl ether isolated from whale blubber
- 2010
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Ingår i: Chemosphere. - : Elsevier. - 0045-6535 .- 1879-1298. ; 79:4, s. 408-413
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Tidskriftsartikel (refereegranskat)abstract
- A previously unidentified yet abundant substituted polybrominated diphenyl ether (PBDE) was isolated from a northern bottlenose whale (Hyperoodon ampullatus) found dead in the Skagerrak, North Sea. A combination of gas chromatography, high and low resolution mass spectrometry and nuclear magnetic resonance spectroscopy (NMR) (1H, 1H–1H and 1H–13C) after isolation with preparative capillary gas chromatography (PCGC) lead to the identification of the unknown substance as 6-MeO-5-Me-2,2′,3,4′-tetrabromo diphenyl ether (6-MeO-5-Me-BDE42). To our knowledge this is only the second time PCGC has been used to isolate individual organohalogen compounds present in trace amounts for identification with NMR. The concentration of this novel bioaccumulated compound was estimated to be about 100 ng g−1 lipid, which was 2.5 times higher compared with the most abundant MeO-PBDE congeners.
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- Unger, Maria, 1980-
(författare)
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Identification of brominated organic compounds in aquatic biota and exploration of bromine isotope analysis for source apportionment
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Brominated organic compounds (BOCs) of both natural and anthropogenic origin are abundant in the environment. Most compounds are either clearly natural or clearly anthropogenic but some are of either mixed or uncertain origin. This thesis aims to identify some naturally produced BOCs and to develop a method for analysis of the bromine isotopic composition in BOCs found in the environment. Polybrominated dibenzo-p-dioxins (PBDDs) in the Baltic Sea are believed to be of natural origin although their source is unknown. Since marine sponges are major producers of brominated natural products in tropical waters, BOCs were quantified in a sponge (Ephydatia fluviatilis) from the Baltic Sea (Paper I). The results showed that the sponge does not seem to be a major producer of PBDDs in the Baltic Sea. In this study, mixed brominated/chlorinated dibenzo-p-dioxins were however discovered for the first time in a background environment without an apparent anthropogenic source. The use of nuclear magnetic resonance spectroscopy (NMR) is unusual in analytical environmental chemistry due to its sample requirements. Preparative capillary gas chromatography was used to isolate a sufficient amount of an unidentified BOC from northern bottlenose whale (Hyperoodon ampullatus) blubber (Paper II) to enable NMR analysis for identification of the compound. The bromine isotopic composition of BOCs may give information on the origin and environmental fate of these compounds. The first steps in this process are the development of a method to determine the bromine isotope ratio in environmentally relevant BOCs (Paper III) and measuring the bromine isotope ratio of several standard substances to establish an anthropogenic endpoint (Paper IV).
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