Identification of highly brominated analogues of Q1 in marine mammals

Abstract

Capsule:Three compounds bioaccumulated in marine mammals were identified as C 9 H 3 N 2 Br 6 Cl, C 9 H 3 N 2 Br 7 and C 9 H 4 N 2 Br 5 Cl and are proposed to be 1'-methyl-1,2'-bipyrrole natural products.Keywords: bioaccumulation, halogenated organic compound, high resolution mass spectrometry, halogenated bipyrrole.* Corresponding author phone: +1 (508) 289-2641; fax: +1 (508) 457-2146; email: eteuten@whoi.edu. 1 AbstractThree novel halogenated organic compounds (HOCs) have been identified in the blubber of marine mammals from coastal New England with the molecular formulae C 9 H 3 N 2 Br 6 Cl, C 9 H 3 N 2 Br 7 , and C 9 H 4 N 2 Br 5 Cl. They were identified using high and low resolution electron ionization (EI) and electron capture negative ionization (ECNI) gas chromatography mass spectrometry (GCMS) and appear to be highly brominated analogues of Q1, a heptachlorinated HOC that has been suspected to be naturally-produced. These new compounds were found in Atlantic white sided dolphin (Lagenorhynchus acutus), bottlenose dolphin (Tursiops truncatus), common dolphin (Delphinus delphis), Risso's dolphin (Grampus griseus), harbor porpoise (Phocoena phocoena), beluga whale (Delphinapterus leucas), fin whale (Balaenoptera physalus), grey seal (Halichoerus grypus), harp seal (Phoca groenlandica) and a potential food source (Loligo pealei) with concentrations as high as 2.7 μg/g (lipid weight). The regiospecificity of C 9 H 3 N 2 Br 6 Cl is suggestive of a biogenic origin. Debromination of C 9 H 3 N 2 Br 6 Cl may be significant in the formation of C 9 H 4 N 2 Br 5 Cl.

Nontargeted Screening of Halogenated Organic Compounds in Bottlenose Dolphins (Tursiops truncatus) from Rio de Janeiro, Brazil

“…In total, we catalogued 5 isomers of MBP-Cl 6 (p. 88–92), MBP-Cl 7 (p. 93), 9 isomers of DMBPs (DMBP-Cl 6 , DMBP-Br 6 , DMBPBrCl 5 , DMBP-Br 3 Cl 2 , DMBP-Br 3 Cl 3 , DMBP-Br 4 Cl 2 and 3 isomers of DMBP-Br 2 Cl 4, p. 79–87). In contrast to the predominance of DMBPs relative to MBPs in dolphins from the northern hemisphere 46–48 , our samples exhibited the opposite trend, with MBPs in greater abundance than DMBPs. This trend is consistent with results reported for marine mammals from Australia 48–50 .…”

Compound‐specific 81Br/79Br analysis by capillary gas chromatography/multicollector inductively coupled plasma mass spectrometry

“…Such excellent precision, which is the most important factor for GC‐based isotopic measurements,25 should pave the way for future studies employing this technique. Such amounts of the necessary Br can easily be obtained 8, 13, 34. For example, a routine extraction and isolation of a brominated compound from a fin whale (C 13 H 8 O 2 Br 4 ) will yield 24 ng or 0.3 nmol of Br in a 2 out of 20 µL injection 8…”

Halogenated organic compounds in archived whale oil: A pre-industrial record

“…Other possibly natural HOCs include a dimethoxylated polybrominated biphenyl (diMeO-PBBs) (Marsh et al, 2005), polybrominated dibenzodioxins (Malmvärn et al, 2005), tetrabrominated carbazoles (Zhu & Hites, 2005), polychlorinated biphenyl carboxylic acids (Repeta et al, 2004) and a family of halogenated 1,2'-methyl bipyrroles (MBPs) (Vetter et al, 1999(Vetter et al, , 2000Teuten et al, 2006a). The heptachlorinated MBP (referred to as Q1) has been found in breast milk of Faroe islanders who eat a diet rich in whale blubber (Vetter et al, 2000).…”