Article

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

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Abstract

To provide additional evidence that several halogenated organic compounds (HOCs) found in environmental samples are natural and not industrially produced, we analyzed an archived whale oil sample collected in 1921 from the last voyage of the whaling ship Charles W. Morgan. This sample, which pre-dates large-scale industrial manufacture of HOCs, contained two methoxylated polybrominated diphenyl ethers (MeO-PBDEs), five halogenated methyl bipyrroles (MBPs), one halogenated dimethyl bipyrrole (DMBP), and tentatively one dimethoxylated polybrominated biphenyl (diMeO-PBB). This result indicates, at least in part, a natural source of the latter compounds.

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... MeO-PBDEs can biomagnify through the trophic web just as the corresponding anthropogenic PBDEs, and were found in considerable concentrations in top predator marine birds and mammals (Losada et al., 2009;Weijs et al., 2009b). These compounds are proposed to have a natural origin and have been present in the marine environment for centuries (Teuten et al., 2005;Teuten and Reddy, 2007;Vetter, 2006). Teuten et al. (2005) confirmed that MeO-PBDEs have a natural origin through the detection of these compounds in oil samples of the true beaked whale (Mesoplodon mirus) from the1920s (Teuten and Reddy, 2007). ...
... These compounds are proposed to have a natural origin and have been present in the marine environment for centuries (Teuten et al., 2005;Teuten and Reddy, 2007;Vetter, 2006). Teuten et al. (2005) confirmed that MeO-PBDEs have a natural origin through the detection of these compounds in oil samples of the true beaked whale (Mesoplodon mirus) from the1920s (Teuten and Reddy, 2007). ...
... Using 14 C stable isotope analysis 6-MeO-BDE-47 and 2 0 -MeO-BDE-68 isolated from North Atlantic True's beaked whales (Mesoplodon mirus) were determined to be natural compounds (Teuten et al., 2005). These compounds were also identified in archived whale oil collected in 1921, before production of synthetic PBDEs (Teuten and Reddy, 2007). Temporal trends of 6-MeO-BDE-47 and 2 0 -MeO-BDE-68 in pike from Swedish waters from 1967 to 2000 were different than those of PBDEs. ...
Article
Brominated compounds are ubiquitous in the aquatic environment. The polybrominated diphenyl ether (PBDE) flame retardants are anthropogenic compounds of concern. Studies suggest that PBDEs can be biotransformed to hydroxylated brominated diphenyl ethers (OH-BDE). However, the rate of OH-BDE formation observed has been extremely small. OH-BDEs have also been identified as natural compounds produced by some marine invertebrates. Another class of compounds, the methoxylated BDEs (MeO-BDEs), has also been identified as natural compounds in the marine environment. Both the OH-BDEs and MeO-BDEs bioaccumulate in higher marine organisms. Recent studies have demonstrated that MeO-BDEs can be biotransformed to OH-BDEs and this generates greater amounts of OH-BDEs than could be generated from PBDEs. Consequently, MeO-BDEs likely represent the primary source of metabolically derived OH-BDEs. Given that for some endpoints OH-BDEs often exhibit greater toxicity compared to PBDEs, it is prudent to consider OH-BDEs as chemicals of concern, despite their seemingly "natural" origins.
... 12,17,51,53 In the Brazilian dolphins, DMBPs contained bromines and/ or chlorines with a slight predominance of chlorination over bromination, opposite to the trend in dolphins from the northern hemisphere. 13,16,17,47 DMBP Br 2 C l4 2 and DMBP Br 2 Cl 4 3 (pp 83 and 84) are reported for the first time. ...
... The bioaccumulating HNPs include two tetrabromophenoxyanisoles (Asplund et al., 1999;Vetter et al., 2002a;Teuten et al., 2005), two polyhalogenated hexahydroxanthene derivatives (Hiebl et al., 2006;Melcher et al., 2007), and several polybrominated dibenzop-dioxins (Haglund et al., 2007). The natural producers (sponges, algae and cyanobacteria) have been identified, and/or their natural origin has been elucidated with radiocarbon measurements or by their detection in pre-industrial samples (Teuten et al., 2005;Reddy and Teuten, 2007). ...
Article
The halogenated natural product previously named mixed-halogenated compound 1 (MHC-1) was isolated from the red seaweed Plocamium cartilagineum harvested in Helgoland, Germany. A total of 1.9 mg of pure MHC-1 was obtained from 1g air-dried seaweed. The 1H and 13C NMR data matched those reported for a natural monoterpene isolated from this species. Thus, the structure of MHC-1 was established to be (1R,2S,4R,5R,1'E)-2-bromo-1-bromomethyl-1,4-dichloro-5-(2'-chloroethenyl)-5-methylcyclohexane. Moreover, the isolated monoterpene proved to be identical with the compound previously detected in marine mammals and fish from different locations. In addition we examined two samples of P. cartilagineum from Ireland and from the Antarctic; however MHC-1 was only present at low levels. Not only the concentrations were lower but also the pattern of polybrominated compounds differed from MHC-1. A calibrated solution of MHC-1 was used to determine correct concentrations from samples where previously only estimates existed relative to the gas chromatography-electron capture detector (GC/ECD) response of trans-chlordane, which underrated the MHC-1 concentrations by more than factor 2. The highest MHC-1 concentration determined to date in marine mammals is 0.14 mg kg(-1) blubber. Significantly higher MHC-1 concentrations were determined in farmed fish with up to 2.2 mg kg(-1) lipids. The samples with high concentrations of MHC-1 have in common that they were collected in proximity of the natural habitats of P. cartilagineum.
... MeO-BDEs are primarily natural products formed by different species, including marine sponges in tropical waters (Utkina and Denisenko, 2006) as well as algae (Malmvärn et al., 2005Malmvärn et al., , 2008) and sponges in the Baltic Sea (Unger et al., 2009). By measuring a contemporary 14 C signal, Teuten et al. (2005) demonstrated that the MeO-PBDEs present in whale blubber are natural products, and two years later the presence of MeO-PBDE in pre-industrial whale oil was reported (Teuten and Reddy, 2007). ...
... Natural compounds probably have been present in the environment for longer time periods than those industrially synthesized. In case of compounds derived from industrial activity, their source, mode of production, fate, impact, and whether their emission can or needs to be controlled should be contemplated (24). ...
Article
The interest in chlorinated volatile organic compounds is not a new task but still draws the attention of scientists. The role they play in human organism, is an important aspect to consider, since the development of analytical techniques and instrumental solutions gives new possibilities of their application in the analytics of volatile compounds and recognition of properties, so far impossible to achieve. Regarded mostly as xenobiotics, these compounds become a challenge for analysts aiming at sample preparation, which will ensure a high value of the analyte's enrichment factor, its determination on the lowest possible concentration level, without excluding the quality of analytical results. Current contributions review issues of environmental fate of halogenated compounds with a special emphasis on chlorinated volatiles, their toxicity, and bioaccumulation in living organisms. Focusing on analytical techniques, overviews include several sampling, preconcentration, and detection methods exemplified by measurements in air, water, and other matrices, including living organisms (e.g., human breath).
... MeO-PBDEs have been identified as natural products by determination of radiocarbon ( 14 C) content of two MeO-PBDEs (6-MeO-BDE47 and 2'-MeO-BDE68) isolated from a True's beaked whale (Mesoplodon mirus) [46]. MeO-PBDEs have also been identified in a whale oil sample from 1921, sampled before any industrial production of OHCs started [47]. For many years no MeO-PBDEs metabolites have been indicated due to PBDE exposure, and accordingly considered to be solely of natural origin. ...
Thesis
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The semi-enclosed and brackish Baltic Sea has become heavily polluted by nutrients, anthropogenic organic and inorganic chemicals via human activities. Persistent organic pollutants (POPs) have been thoroughly investigated due to their linkage to toxic effects observed in Baltic biota. There has been far less focus on semi-persistent pollutants e.g. naturally produced oraganohalogen compounds (NOCs) and their disturbances in the environment. This thesis is aimed on assessment of levels and trends of naturally produced brominated compounds in Baltic biota; more specifically on hydroxylated polybrominated diphenyl ethers (OH-PBDEs), methoxylated PBDEs (MeO-PBDEs) and polybrominated dibenzo-p-dioxins (PBDDs). These, NOCs, may originate from production in algae and cyanobacteria. OH-PBDEs and MeO-PBDEs may also be formed as metabolites of polybrominated diphenyl ethers (PBDEs), i.e. wellknown commercial flame retardants. High levels of OH-PBDEs, MeO-PBDEs and PBDDs are shown within Baltic biota (cyanobacteria, algae, mussels, fish), often in much higher concentrations than PBDEs which are possible anthropogenic precursors of OH- and MeOPBDEs. The levels of OH-PBDEs, MeO-PBDEs and PBDDs are higher in the Baltic Sea than on the west coast of Sweden. Temporal and seasonal variations show fluctuations in concentrations of OH-PBDEs, MeO-PBDEs and PBDDs, possibly related with macroalgal life-cycles. OH-PBDEs, MeO-PBDEs and PBDDs are present in several filamentous macroalgae species, but considering the levels quantified, the time of peak exposure and the species life-cycle the macroalgae, Pilayella, Ceramium and Cladophora are suggested as major natural producers of OH-PBDEs and PBDDs. The high levels of OH-PBDEs, MeO-PBDEs and PBDDs in the Baltic Sea may affect numerous organisms in the ecosystem. The toxic effects of OH-PBDEs and PBDDs are of particular concern. This thesis stress the importance of assessing and monitoring these substances, since the exposure to OH-PBDEs and PBDDs, during summer, may cause acute effects in Baltic fish and wildlife.
... The source of chlorine in this sample is likely a residue from the HCl used to acidify the water before solid-phase (C 18 ) extraction of the dissolved organic matter, as dissolved chlorine concentrations in Lake Drummond are quite low (9 mg/L) relative to dissolved organic carbon concentrations (105 mg/L) (Johannesson et al. 2004). Nevertheless, natural organo-chlorine species are well documented, and we cannot rule out the possibility that they are preexisting components of Lake Drummond NOM (Myneni 2002;Repeta et al. 2004;Leri et al. 2007;Teuten and Reddy 2007). ...
Article
Full-text available
Introduction Determining the molecular identity of organic molecules in natural waters is fundamental to understanding the origin, reactivity, and environmental fate of natural and anthro-pogenic compounds. The composition of dissolved organic matter is relevant to issues of drinking water quality, aquatic ecology, biogeochemical cycling, and many others. The answers to fundamental questions, such as, "What happens to terrestrial organic matter in the Ocean?"(Hedges et al. 1997), require molecular information about terrestrial and marine end members. Nevertheless, more than half of the organic matter in natural waters is uncharacterized at the molecular level (Hedges et al. 2000). Recent advances in nuclear magnetic res-onance (NMR) (see review by Cardoza et al. 2004) and the use of modeling for interpretation of complex NMR spectra have Abstract Fourier-transform ion cyclotron resonance mass spectrometry (MS) has demonstrated potential to revolution-ize the fields of limnology and chemical oceanography by identifying the individual molecular components of organic matter in natural waters. The use of MS for this purpose is made possible by the electrospray technique which successfully ionizes polar, nonvolatile organic molecules. Another recently developed ion source, atmos-pheric pressure photoionization (APPI), extends MS capabilities to less polar molecules. This article presents early results on the application of APPI MS to natural organic matter. We compare APPI MS and electrospray MS data for dissolved organic matter from Lake Drummond (Virginia, USA). Collectively, electrospray and APPI MS iden-tify more than 6000 molecular species to which we assign unique molecular formulas. Fewer than 1000 molecu-lar species are common to both electrospray and APPI mass spectra, indicating that the techniques are highly complementary in the types of molecules they ionize. Access to a broad range of molecules provided by com-bining APPI and electrospray has prompted a qualitative analysis. The goal is to assess the extent to which molec-ular MS data correspond with elemental (CHNOS) and structural characteristics determined by combustion ele-mental analyses and 13 C nuclear magnetic resonance (NMR). Because the data obtained by these different meth-ods are not directly comparable, we propose a novel data analysis procedure that facilitates their comparison. The bulk elemental composition calculated from electrospray MS data are in close agreement (± 15%) with values determined by combustion elemental analysis. APPI and electrospray MS detect protein contributions in agree-ment with 13 C NMR (6 wt %) but underestimate carbohydrates relative to 13 C NMR. Nevertheless, MS results agree with NMR on the relative proportions of noncarbohydrate compounds in the organic matter: lignins > lipids > peptides. Finally, we use a molecular mixing model to simulate a 13 C NMR spectrum from the MS datasets. The correspondence of the simulated and measured 13 C NMR signals (74%) suggests that, collectively, the molecular species identified by APPI and electrospray MS comprise a large portion of the organic matter in Lake Drummond. These results add credibility to electrospray and APPI MS in limnology and oceanography applications, but fur-ther characterization of ion source behavior is fundamental to the accurate interpretation of MS data.
... Today there are several additional reports showing their presence in marine food webs globally [73,[122][123][124]. The natural origin of 6-MeO-BDE47 and 2'-MeO-BDE68 (Figure 2.10) has been proven by 14 C measurements [125], and both have been quantified in a whale oil sample dated in 1929, collected prior to any large-scale production of industrial chemicals [126]. OH-PBDEs may however also be formed as metabolites of PBDEs (see Chapter 2.1). ...
... Photochemical formation of OH-PBDEs from 2,4-BP has also been reported . The structurally related methoxylated polybrominated diphenylethers (MeO-PBDEs) are primarily of natural origin (Haglund et al., 1997;Teuten and Reddy, 2007;Teuten et al., 2005). The interconversion of MeO-PBDEs to OH-PBDEs has been shown both in vitro and in vivo (Wan et al., 2009;Wan et al., 2010). ...
Article
Polybrominated dibenzo-p-dioxins (PBDD) and dibenzofurans (PBDF) are a group of compounds of emerging interest as potential environmental stressors. Their structures as well as toxic responses are similar to the highly characterized toxicants polychlorinated dibenzo-p-dioxins. High levels of PBDDs have been found in algae, shellfish and fish, even from remote areas in the Baltic Sea. The geographical and temporal variations of PBDD in biota samples suggests natural rather than anthropogenic origins. The work underlying this thesis investigated the retention and transfer behavior, as well as health and reproductive effects, of PBDD/Fs in fish, to further increase the knowledge on persistency, retention and effects of PBDD/Fs, specifically concerning influence of substitution pattern and physico-chemical properties. In addition, biotic and abiotic formation of PBDDs from naturally abundant phenolic precursors were explored, to evaluate whether the PBDD profiles found in Baltic Sea biota can be explained by natural formation processes.
... Methoxylated PBDEs (MeO-PBDEs) have been evidenced in marine environments, with the tetrabrominated 2'-MeO-BDE 68 and 6-MeO-BDE 47 being the most abundant compounds (Vetter et al., 2002). MeO-PBDEs have been reported as having a natural origin (Teuten and Reddy, 2007;Teuten et al., 2005), being formed by sponges (Vetter et al., 2002) or algae (Malmvärn et al., 2005). However, biotransformation of hydroxylated PBDEs (OH-PBDEs) to MeO-PBDEs has also been demonstrated (Wan et al., 2010). ...
Article
The study documents the levels and profiles of selected contaminants [polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs) and methoxylated PBDEs (MeO-PBDEs)] in blubber biopsy samples collected from humpback whales (Megaptera novaeangliae) in Antarctic Peninsula waters. In addition, we investigated year-to-year and sex-related differences in the bioaccumulation patterns. Except for hexachlorobenzene (HCB), whose concentrations were in the same range as those found in whales from the Northern Hemisphere, levels of all other compounds were lower in Southern Hemisphere whales compared to literature data on animals from the Arctic and subarctic region. The mean contribution to the sum of all anthropogenic organohalogen compounds (ΣOHC) decreased in the following order ΣPCBs (44%)>HCB (31%)>ΣDDXs (13%)>ΣCHLs (4.6%)>ΣHCHs (4.4%)>ΣPBDEs (0.9%). The predominant compounds within each chemical class were: PCBs 153, 149, 101 and 138; p,p'-DDE; γ-HCH; trans-nonachlor; PBDEs 99 and 47. The most dominant MeO-PBDE congener was 6-MeO-BDE 47. As samples were collected during three consecutive summer seasons, year-to-year trends could be assessed indicating a significant decrease from 2000 to 2003 for ΣCHL levels. Higher ΣPBDE concentrations and higher values of the ΣPBDE / ΣMeO-PBDE ratio, as well as higher ratios between the two MeO-BDEs (2'-MeO-BDE 68/6-MeO-BDE 47) were found in females compared to males. Higher ΣMeO-PBDE concentrations and higher values of the ratios between the lower chlorinated and the higher chlorinated PCBs were found in males than in females. In addition, five out of six significant differences found through discriminant function analysis were gender-related. The literature reports both feeding in mid- to low-latitudes and sex-related differences in migration patterns for humpback whales from the Southern Hemisphere, indicating that the hypothesis of dietary differences between males and females cannot be excluded. Nevertheless, additional studies are required for further investigation of this hypothesis. Copyright © 2015 Elsevier Inc. All rights reserved.
... This is evidenced by the correlation between the environmental levels and human activities, such as an increase after thriving manufacturing and a decrease after improvement of wastewater treatment (Guo et al., 2014;Heim et al., 2004;Zhu and Hites, 2005). In addition, before large-scale industrial activities contributed to the presence of carbazoles, non-or very low-detectable concentrations were found in whale oil and sediment (Teuten and Reddy, 2007;Zhu and Hites, 2005). ...
Article
Carbazole and some of its derivatives may possess dioxin-like toxicity and could be persistent in the environment, but information on their distribution and environmental fate is limited. This study developed and validated an ultra-trace targeted-analysis method for the determination of carbazole, 1,2-benzocarbazole, and 13 halogenated carbazoles in sediments from the river, coast, and North Sea. An 8-g sediment sample was extracted using accelerated solvent extraction combined with in-cell cleanup and analyzed using gas chromatography-tandem mass spectrometry. The method was sensitive and reliable with method detection limits ranging from 4.54 to 52.9 pg/g, and most of the quantification biases and relative standard deviations were <20 and <15%, respectively. Carbazole and 1,2-benzocarbazole were the predominant substances in the sediments (median 565 and 369 pg/g, respectively) followed by 3,6-dichlorocarbazole (median 196 pg/g). The detection frequencies of carbazole, benzo-, 3-chloro-, and 3,6-dichlorocarbazole were >75%, while those of 3,6-dibromo-, 1-bromo-3,6-dichloro-, and 1,8-dibromo-3,6-dichlorocarbazole were approximately 50%. Brominated carbazoles occurred more frequently in marine than river-influenced sediments, which could indicate halogenation after discharge into the river. This is the first study regarding these substances in coastal environments without apparent contamination history. The ubiquity and bioaccumulative potential of these substances needs to be considered.
... OH-BDEs and MeO-BDEs are also transformation products of polybrominated diphenyl ether (PBDE) flame retardants (Wiseman et al., 2011), and substitution patterns give clues to natural versus anthropogenic origins (Agarwal et al., 2015;Marsh et al., 2004;Wiseman et al., 2011). Natural origin of the more abundant MeO-BDEs has been confirmed by 14 C dating (Guitart et al., 2011;Teuten et al., 2005) and by their presence in historical specimens: archived whale oil from the pre-industrial period (Teuten and Reddy, 2007) and a sea eagle egg laid in 1941 in the Baltic region (Nordlöf et al., 2012). They occur in deep layers of ocean sediments (Fan et al., 2014a(Fan et al., , 2014b. ...
Article
Halogenated natural products in biota of the Baltic Sea include bromoanisoles (BAs) and methoxylated bromodiphenyl ethers (MeO-BDEs). We identified biogenic 6-MeO-BDE47 and 2'-MeO-BDE68 in Baltic water and air for the first time using gas chromatography - high resolution mass spectrometry. Partial pressures in air were related to temperature by: log p/Pa=m/T(K)+b. We determined Henry's law constants (HLCs) of 2,4-dibromoanisole (2,4-DiBA) and 2,4,6-tribromoanisole (2,4,6-TriBA) from 5 to 30°C and revised our assessment of gas exchange in the northern Baltic. The new water/air fugacity ratios (FRs) were lower, but still indicated net volatilization in May-June for 2,4-DiBA and May - September for 2,4,6-TriBA. The net flux (negative) of BAs from Bothnian Bay (38,000km(2)) between May - September was revised from -1319 to -532kg. FRs of MeO-BDEs were >1, suggesting volatilization, although this is tentative due to uncertainties in their HLCs and binding to dissolved organic carbon.
... The continuing presence of 1,3,6,8-tetrabromocarbazole at depths indicated by hundreds or thousands of years below the 30 cm depth at these locations would be strong evidence for natural sources playing a significant role in its presence in the environment. Persistent halogenated organic chemicals are known to accumulate in the fatty tissue of marine animals, but 1,3,6,8-tetrabromocarbazole was not detected in archived whale oil from 1921 (Teuten and Reddy, 2007), lending support to it not being a widespread contaminant in the environment prior to this time. ...
Article
In recent years, a number of halogenated carbazoles have been detected in environmental samples. These emerging contaminants have been shown to be persistent and possess dioxin-like toxicological potential. The goal of this research was to examine the literature to determine likely anthropogenic origin(s) of halogenated carbazoles in the environment. The scientific literature indicated a number of pathways by which 1,3,6,8-tetrabromocarbazole could form in the manufacture of 5,5',7,7'-tetrabromoindigo. The U.S. production history of 5,5',7,7'-tetrabromoindigo correlates well with the concentration rise, decline, and disappearance of 1,3,6,8-tetrabromocarbazole in dated Lake Michigan sediments. Additionally, other halogenated carbazoles that have been found in environmental sediments can be explained by the production of other halogenated indigo dyes. 1,8-dibromo-3,6-dichlorocarbazole can be accounted for by the manufacture of 7,7'-dibromo-5,5'-dichloroindigo, while 1,3,6,8-tetrachlorocarbazole was found at relatively high concentration near the outfall of a U.S. manufacturer of 5,5',7,7'-tetrachloroindigo. Carbazoles containing an iodo-substituent can be explained by the use of iodine as a catalyst in the manufacture of halogenated indigo dyes. 3,6-Dichlorocarbazole measured in soils and dibromocarbazoles measured in more recently deposited sediments are not easily rationalized on the basis of an indigo related source and may be related to other anthropogenic sources or natural origins. Copyright © 2015 Elsevier Ltd. All rights reserved.
... Far less information is available about the fate of organochlorine compounds from natural sources. However, the fact that these compounds can be found in higher food webs such as marine mammals (Teuten and Reddy, 2007) and ultimately humans (Wang et al., 2012) shows their recalcitrance, owing to their persistence and bioaccumulative properties. Similarly, chlorine compounds originating from pharmaceuticals and personal care products that usually occur at micropollutant concentrations (µg-ng range) are widely found in the environment, indicating their recalcitrance to microbial metabolism (Atashgahi et al., 2018d). ...
Article
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Organic and inorganic chlorine compounds are formed by a broad range of natural geochemical, photochemical and biological processes. In addition, chlorine compounds are produced in large quantities for industrial, agricultural and pharmaceutical purposes, which has led to widespread environmental pollution. Abiotic transformations and microbial metabolism of inorganic and organic chlorine compounds combined with human activities constitute the chlorine cycle on Earth. Naturally occurring organochlorines compounds are synthesized and transformed by diverse groups of (micro)organisms in the presence or absence of oxygen. In turn, anthropogenic chlorine contaminants may be degraded under natural or stimulated conditions. Here, we review phylogeny, biochemistry and ecology of microorganisms mediating chlorination and dechlorination processes. In addition, the co-occurrence and potential interdependency of catabolic and anabolic transformations of natural and synthetic chlorine compounds are discussed for selected microorganisms and particular ecosystems.
... Starting in the late 1920s, PBDEs were produced industrially and used as flame-retardants in a wide variety of products such as electronics and textiles (Johnson-Restrepo and Kannan, 2009). While anthropogenic PBDEs can be introduced into the ocean via surface runoff, there is increasing evidence that these compounds are also produced naturally in the marine environment (Reddy et al., 2004;Teuten and Reddy, 2007). Due to their lipophilicity, these molecules bioaccumulate in the blubber and tissues of marine mammals, thus suggesting that a human diet rich in seafood could lead to increased PBDE exposure (Venkateswaran and Dohmoto, 2000;Malmvärn et al., 2005;Teuten et al., 2005). ...
Article
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The production of pentabromopseudilin and related brominated compounds by Pseudoalteromonas spp. has recently been linked to the bmp biosynthetic gene cluster. This study explored the distribution and evolutionary history of this gene cluster in the genus Pseudoalteromonas. A phylogeny of the genus revealed numerous clades that do not contain type strains, suggesting considerable species level diversity has yet to be described. Comparative genomics revealed four distinct versions of the gene cluster distributed among 19 of the 101 Pseudoalteromonas genomes examined. These were largely localized to the least inclusive clades containing the P. luteoviolacea and P. phenolica type strains and show clear evidence of gene and gene cluster loss in certain lineages. Bmp gene phylogeny is largely congruent with the Pseudoalteromonas species phylogeny, suggesting vertical inheritance within the genus. However, the gene cluster is found in three different genomic environments suggesting either chromosomal rearrangement or multiple acquisition events. Bmp conservation within certain lineages suggests the encoded products are highly relevant to the ecology of these bacteria. This article is protected by copyright. All rights reserved.
... eggshell thinning in birds (Blus et al., 1972), embryotoxicity (Brunstr€ om and Reutergårdh, 1986) and effects on reproductive behaviour (Fernie et al., 2008), the production of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDEs) has been restricted by the UN Stockholm Convention on persistent organic pollutants (POPs) (United Nations Environment Program; www.pops.int). Unlike other OHCs, methoxylated polybrominated diphenyl ethers (MeO-PBDEs) have natural sources in the oceanic food web (Teuten et al., 2005;Teuten and Reddy, 2007). Since OHCs are generally lipophilic, they tend to accumulate through the food web and are stored in body fat reserves. ...
Article
Although many studies have investigated organohalogenated contaminants (OHCs) in yolk, little is known about the mechanisms and timing of transfer of OHCs from the female to the egg. Vitellogenin, a yolk precursor, has been suggested to play a role in this transport. We here report for the first time the temporal changes in OHC and an index of vitellogenin concentrations in female plasma from the pre-laying period to clutch completion in free-living birds: the southern rockhopper penguin (Eudyptes chrysocome chrysocome) breeding in the Falkland/Malvinas Islands. In addition, OHC concentrations in the corresponding clutches were analysed. OHC concentrations in female plasma and in the yolk of both the first (A-) and the second (B-)eggs followed a similar pattern, with hexachlorobenzene (HCB) > Σpolychlorinated biphenyls (PCBs) > Σdichlorodiphenyltrichloroethanes (DDTs) > Σmethoxylated polybrominated diphenyl ethers (MeO-PBDEs) > Σchlordanes (CHLs) > Σpolybrominated diphenyl ethers (PBDEs) ≈ Σhexachlorocyclohexanes (HCHs). The higher concentrations of MeO-PBDEs compared to PBDEs indicate a diet containing naturally-produced MeO-PBDEs. All OHC compounds except for PBDEs increased from the pre-laying period to A-egg laying and subsequently declined from A-egg laying to B-egg laying, and female plasma vitellogenin showed the same pattern. For ΣPCBs and ΣMeO-PBDEs, we found positive correlations between female plasma during A-egg laying and both eggs, and for HCB between female plasma and A-eggs only. During pre-laying, only ΣMeO-PBDEs correlated between both eggs and female plasma, and no correlations between OHC concentrations in eggs and female plasma were found during B-egg laying, highlighting that maternal transfer of OHCs is time- and compound-specific. Finally, female vitellogenin concentrations did not significantly correlate with any OHC compounds in either female plasma or eggs, and our results therefore did not confirm the suggested role of vitellogenin in the maternal transfer of OHC molecules into their eggs.
... The endocrine-disrupting flame retardant polybrominated diphenyl ethers have natural counterparts that are produced by marine sponges (Agarwal et al., 2017) at levels that can exceed 10% of the sponge tissue dry weight (Unson et al., 1994). Naturally produced organohalogens were reported to bioaccumulate in marine mammals (Vetter et al., 2002;Teuten and Reddy, 2007) and humans (Wan et al., 2010;Wang et al., 2012) indicating human contact through the marine food web. Accordingly, POPs can come into contact with humans primarily through dietary intake including fatty fish, red meat and poultry (Kiviranta et al., 2004;Schecter et al., 2010), but also through inhalation and dermal absorption (Besis and Samara, 2012). ...
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Humans and their associated microbiomes are exposed to numerous xenobiotics through drugs, dietary components, personal care products as well as environmental chemicals. Most of the reciprocal interactions between the microbiota and xenobiotics, such as halogenated compounds, occur within the human gut harboring diverse and dense microbial communities. Here, we provide an overview of the flux of halogenated compounds in the environment, and diverse exposure routes of human microbiota to these compounds. Subsequently, we review the impact of halogenated compounds in perturbing the structure and function of gut microbiota and host cells. In turn, cultivation-dependent and metagenomic surveys of dehalogenating genes revealed the potential of the gut microbiota to chemically alter halogenated xenobiotics and impact their fate. Finally, we provide an outlook for future research to draw attention and attract interest to study the bidirectional impact of halogenated and other xenobiotic compounds and the gut microbiota.
... In 2016, HNPs had been recognized as emerging contaminants by the Arctic Monitoring and Assessment Programme (AMAP) (Wilson 2018). Although HNPs have been detected in many marine regions worldwide (Alonso et al. 2017;Goto et al. 2020;Löfstrand et al. 2010;Malmvärn et al. 2005;Shaul et al. 2015;Teuten and Reddy 2007;Wu et al. 2019), one commonly known hotspot of HNPs is the Great Barrier Reef in Australia (Vetter et al. 2001(Vetter et al. , 2002(Vetter et al. , 2009. Several HNPs such as 2,3,3′,4,4′,5,5′-heptachloro-1′-methyl-1,2′-bipyrrole (Q1) or the tetrabrominated methoxylated diphenyl ethers (2′-MeO-BDE 68 or BC-2, and 6-MeO-BDE 47 or BC-3) were detected at ppm-levels in marine mammals inhabiting the Great Barrier Reef (Fig. 1a-i), thus confirming their bioaccumulative nature (Vetter et al. 2001(Vetter et al. , 2002. ...
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Concentrations, profiles and muscle-liver distribution of halogenated natural products (HNPs) and anthropogenic persistent organic pollutants (POPs) were investigated in five large pelagic fish species and one smaller planktivore fish species from the Western Indian Ocean. Analysis of swordfish muscle from the Seychelles revealed the predominance of HNPs, with the highest concentrations found for 2′-methoxy-2,3′,4,5′-tetraBDE (2′-MeO-BDE 68 or BC-2), 6-methoxy-2,2′,4,4′-tetraBDE (6-MeO-BDE 47 or BC-3) and 2,3,3′,4,4′,5,5′-heptachloro-1′-methyl-1,2′-bipyrrole (Q1), along with varied contributions of further HNPs. The mean concentration of ∑HNPs (330 ng/g lw) was one or two orders of magnitude higher than ∑DDTs (60 ng/g lw) and ∑PCBs (6.8 ng/g lw). HNPs (BC-2, BC-3 and Q1) were also predominant in individual samples of three tropical tuna species from the Seychelles and from other regions of the Western Indian Ocean (Mozambique Channel, off Somalia and Chagos Archipelago). Non-targeted gas chromatography coupled with electron capture negative ion mass spectrometry operated in the selected ion monitoring mode (GC/ECNI-MS-SIM) analysis of one swordfish sample indicated low abundance of rarely reported HNPs (three hexachloro-1′-methyl-1,2′-bipyrrole (Cl 6-MBP) isomers and pentabromo-1,1′-dimethyl-2,2′-bipyrroles (Br 5-DBP)) but no further abundant unscreened polyhalogenated compounds.
... Studies indicate that MeO-BDEs can be synthetized by aquatic biota (invertebrates and microoganisms) (Agarwal et al., 2014;Teuten, 2005;Vetter et al., 2002), as well as can be biotransformed from PBDEs (Wan et al., 2009). Although some MeO-BDE congeners are considered natural compounds, MeO-BDEs and PBDEs share similarities in their environmental behavior, both group of compounds being lipophilic and acting as endocrine disruptors (Fan et al., 2014a;Liu et al., 2015;Teuten and Reddy, 2007). ...
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Especially added on many industrial and domestic products as flame retardants (FRs), polybrominated diphenyl ethers (PBDEs) are among the chemicals of high environmental concern because of their potential harmfulness for environmental and human health. Seafood consumption is considered the main source of PBDEs and their methoxylated congeners (MeO-BDEs) for humans. The present study aims to investigate the seasonal occurrence of six PBDEs and eight MeO-BDEs congeners using Douro river biota (different trophic levels) as sentinels, as well as to evaluate the human exposure risk to PBDEs through seafood consumption. Biota samples (n = 273) were collected from one of the most important Portuguese estuaries in the north-western coast of Portugal at four different seasons (2019–2020). The analyses were performed by an environmental-friendly extraction procedure followed by Gas Chromatography coupled to a triple quadrupole detector (GC–MS/MS). PBDEs were detected in all seafood samples analysed, with means ranging from 0.02 ng g⁻¹ ww (flounder in autumn) to 3.75 ng g⁻¹ ww (mussel in winter). Levels of lower-brominated PBDE congeners were significantly higher than higher-brominated ones in all seasons (p < 0.01). MeO-BDEs ranged from 0.001 ng g⁻¹ ww (grey mullet in summer) to 5.66 ng g⁻¹ ww (green crab in spring). Crabs and mussels presented the highest means of PBDEs and MeO-BDEs. Regarding the health risk assessment of the studied PBDE congeners (47, 99, and 153), consumption of Douro river fish is not a case of concern for consumers.
... Evidence of natural origin has been obtained by radiocarbon ( 14 C) analysis of 6-OH-BDE47, 2 0 -OH-BDE68, 2 0 ,6-diOH-BDE159, and 2 0 -MeO-6-OH-BDE120 [51,78], and 1,1 0 -dimethyl-3,3 0 ,4,4 0 -tetrabromo-5,5 0 -dichloro-2,2 0 -bipyrrole (DBP-Br 4 Cl 2 ) [79]. Other studies have noted the presence of 6-MeO-BDE47 and 2 0 -MeO-BDE68 in environmental samples that pre-dated the advent of anthropogenic PBDEs; viz. a whale oil sample archived since 1921 [80], sediment layers deposited since the late 1800s to early 1900s in the southern Yellow Sea and East China Sea [38,81] and in an Table S1. c Range of properties for congeners listed in Table S1. ...
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Halogenated natural products (HNPs) are organic compounds containing bromine, chlorine, iodine, and rarely fluorine. HNPs comprise many classes of compounds, ranging in complexity from halocarbons to higher molecular weight compounds, which often contain oxygen and/or nitrogen atoms in addition to halogens. Many HNPs are biosynthesized by marine bacteria, macroalgae, phytoplankton, tunicates, corals, worms, sponges and other invertebrates. This paper reviews HNPs in Arctic, Subarctic and Nordic ecosystems and is based on sections of Chapter 2.16 in the Arctic Monitoring and Assessment Program (AMAP) assessment Chemicals of Emerging Arctic Concern (AMAP, 2017) which deal with the higher molecular weight HNPs. Material is updated and expanded to include more Nordic examples. Much of the chapter is devoted to “bromophenolic” HNPs, viz bromophenols (BPs) and transformation products bromoanisoles (BAs), hydroxylated and methoxylated bromodiphenyl ethers (OH-BDEs, MeO-BDEs) and polybrominated dibenzo-p-dioxins (PBDDs), since these HNPs are most frequently reported. Others discussed are 2,2′-dimethoxy-3,3′,5,5′-tetrabromobiphenyl (2,2′-dimethoxy-BB80), polyhalogenated 1′-methyl-1,2′-bipyrroles (PMBPs), polyhalogenated 1,1′-dimethyl-2,2′-bipyrroles (PDBPs), polyhalogenated N-methylpyrroles (PMPs), polyhalogenated N-methylindoles (PMIs), bromoheptyl- and bromooctyl pyrroles, (1R,2S,4R,5R,1′E)-2-bromo-1-bromomethyl-1,4-dichloro-5-(2′-chloroethenyl)-5-methylcyclohexane (mixed halogenated compound MHC-1), polybrominated hexahydroxanthene derivatives (PBHDs) and polyhalogenated carbazoles (PHCs). Aspects of HNPs covered are physicochemical properties, sources and production, transformation processes, concentrations and trends in the physical environment and biota (marine and freshwater). Toxic properties of some HNPs and a discussion of how climate change might affect HNPs production and distribution are also included. The review concludes with a summary of research needs to better understand the role of HNPs as “chemicals of emerging Arctic concern”.
... In the early 1960's, the intense industrial production and the magnified use of new HOCs, together with indiscriminate disposal practices, led to their widespread entry into the environment, causing harmful effects on exposed biota (Häggblom and Bossert, 2005). In addition to anthropogenic causes, generation of such compounds also occurs naturally, with several HOCs having been found in archived whale oil samples from 1921, before industrial production (Teuten and Reddy, 2007). ...
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Halogenated organic compounds are a particular group of contaminants consisting of a large number of substances, and of great concern due to their persistence in the environment, potential for bioaccumulation and toxicity. Some of these compounds have been classified as persistent organic pollutants (POPs) under The Stockholm Convention and many toxicity assessments have been conducted on them previously. In this work we provide an overview of enzymatic assays used in these studies to establish toxic effects and dose-response relationships. Studies in vivo and in vitro have been considered with a particular emphasis on the impact of halogenated compounds on the activity of relevant enzymes to the humans and the environment. Most information available in the literature focuses on chlorinated compounds, but brominated and fluorinated molecules are also the target of increasing numbers of studies. The enzymes identified can be classified as enzymes: i) the activities of which are affected by the presence of halogenated organic compounds, and ii) those involved in their metabolisation/detoxification resulting in increased activities. In both cases the halogen substituent seems to have an important role in the effects observed. Finally, the use of these enzymes in biosensing tools for monitoring of halogenated compounds is described.
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2,2′-Bipyrroles, which are obvious precursors for the synthesis of 2,2′-bipyrrole-based natural products, are synthesized in three steps from pyrrole employing known pyrrolyl ketoalcohols by a sequential alcohol oxidation and Paal-Knorr pyrrole synthesis.
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The previous survey documented 2,448 naturally occurring organohalogen compounds, both biogenic and abiotic (1). In the intervening years an additional 2,266 compounds have been identified from a myriad of natural sources, which include chlorine-, bromine-, iodine-, and fluorine-containing organic compounds. The organization herein follows that used earlier so as to provide continuity. Numerous reviews covering natural organohalogens, both very general and highly specialized, have appeared since 1994 (2-72). Others will be cited in the appropriate section.
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The present study provides the first comprehensive investigation of polyhalogenated carbazoles (PHCZ) contamination in an aquatic ecosystem. PHCZs have been found in soil and aquatic sediment from several different regions, but knowledge of their bioaccumulation and trophodynamics is extremely scarce. This work investigated a suite of 11 PHCZ congeners in San Francisco Bay (United States) sediment and organisms, including bivalves (n = 6 composites), sport fish (n = 12 composites), harbor seal blubber (n = 18), and bird eggs (n = 8 composites). The most detectable congeners included 3,6-dichlorocarbazole (36-CCZ), 3,6-dibromocarbazole (36-BCZ), 1,3,6-tribromocarbazole (136-BCZ), 1,3,6,8-tetrabromocarbazole (1368-BCZ), and 1,8-dibromo-3,6-dichlorocarbazole (18-B-36-CCZ). The median concentrations of ΣPHCZs were 9.3 ng/g dry weight in sediment and ranged from 33.7 to 164 ng/g lipid weight in various species. Biomagnification was observed from fish to harbor seal and was mainly driven by chlorinated carbazoles, particularly 36-CCZ. Congener compositions of PHCZs differed among species, suggesting that individual congeners may be subject to different bioaccumulation or metabolism in species occupying various trophic levels in the studied aquatic system. Toxic equivalent (TEQ) values of PHCZs were determined based on their relative effect potencies (REP) compared to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The median TEQ was 1.2 pg TEQ/g dry weight in sediment and 4.8 – 19.5 pg TEQ/g lipid weight in biological tissues. Our study demonstrated the broad exposure of PHCZs in San Francisco Bay and their characteristics of bioaccumulation and biomagnification along with dioxin-like effects. These findings raise the need for additional research to better elucidate their sources, environmental behavior, and fate in global environments.
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Polyhalogenated compounds are frequently detected in environmental and food samples. In addition to the man-made industrial chemicals and chloropesticides, a range of halogenated natural products has been identified in marine organisms, among them being different polyhalogenated alkaloids. This article summarizes the current knowledge on residues of polyhalogenated 1,1'-dimethyl-2,2'-bipyrroles, polyhalogenated 1'-methyl-1,2'-bipyrroles, tetrabromo-1-methylpyrrole as well as bromoindoles and bromo-1-methylindoles in environmental and food samples. The data presented include the theoretical and the known variety of congeners, the structures and the verification of their natural origins, concentrations in the marine environment and in human milk, methods suitable for the quantitative determination of polyhalogenated alkaloids, novel nontargeted screening methods, physicochemical parameters, bioactivity, and enantioselective determination of atropisomeric polyhalogenated bipyrroles.
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The number of known natural organohalogen compounds of all types has grown from 30 in 1968 to >5000 today. About 25% of halogenated natural products are alkaloids, mostly found in marine organisms. Several factors account for this extraordinary increase in the sheer number of these structurally fascinating and biologically active compounds - the ceaseless search for new natural products as potential medicinal compounds, the development of improved isolation and characterization techniques, selective bioassays to identify biologically active lead compounds, and an awareness of folk medicine and ethnobotany for guidance to significant organisms. This review surveys the occurrence of halogenated alkaloids.
Zotero is a free and open source Firefox extension that exists within the Web browser and allows one to collect, manage, store, and cite resources in a single location. 1 1. Center for History New Media, George Mason University. Zotero: The Next-Generation Research Tool. 2009. Available: <http://www.zotero.org/>. Accessed: May 13, 2009 . View all references Zotero automatically imports citation information from a number of sources, including nonsubscription, newspaper, and commercial Web sites, and Web-based databases such as PubMed and MedlinePlus. Zotero offers more options for note taking than the better-known citation management system EndNote. Sixteen citation styles are available when Zotero is initially downloaded, with many more freely available. Users can install a plug-in that allows Zotero to integrate with Microsoft Word. Even though Zotero does not have an on-demand customer support service, its Web site offers a wealth of information for users. The authors highly recommend Zotero.
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Analytical methods for contaminant monitoring are generally targeted; i.e., they measure defined lists of compounds. Routine monitoring projects using targeted methods are not usually designed to screen for unrecognized or novel contaminants and therefore miss compounds within the region or population of study that cause, or have the potential to cause, adverse biological impacts. We describe a nontargeted analytical method utilizing direct sample introduction coupled to comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry. To test the capabilities of this instrumental method within the context of marine contaminant surveys, we characterized a broad array of nonpolar, persistent, and bioaccumulative contaminants in Atlantic common dolphin ( Delphinus delphis ) blubber, including compounds that are not typically monitored. Compound identifications were made by searching a standard reference database, by contemporaneously analyzing mass spectra from reference standards, and by de novo interpretation. We identified a total of 271 compounds belonging to 24 classes; all compounds but 1 were halogenated. Anthropogenic contaminants and halogenated natural products were concurrently detected. A total of 86 compounds were anthropogenic contaminants that are not routinely targeted in environmental surveys, and 54 compounds were halogenated natural products. A total of 112 spectra were identified de novo, demonstrating that exclusive reliance on commercially available reference standards and mass spectral libraries may miss a significant fraction of identifiable compounds. We also cataloged 27 halogenated mass spectra that were not able to be identified. Due to the volume and complexity of the identification data, we developed custom software to organize and provide shared access to the identified mass spectra and related information. The nontargeted analytical method and data reporting system, in combination with the analysis of a high-trophic-level sentinel species, demonstrates a framework for creating an inventory of persistent and bioaccumulative contaminants in marine environments, with the future goal of suggesting new compounds for further investigation by targeted monitoring and risk assessment.
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Polybrominated organic compounds are ubiquitous throughout the environment. This generic term comprises several classes of brominated flame retardants (e.g., polybrominated diphenyl ethers, polybrominated biphenyls, hexabromocyclododecane, dibromopropyltribromophenyl ether, 1,2-bis(2,4,6-tribromophenoxy)ethane) as well as a range of marine halogenated natural products (HNPs). Here we present gas chromatography retention times and elution orders (on DB-5) of 122 polybrominated compounds that may be found in food and environmental samples. Organobromine compounds in fish samples determined with gas chromatography interfaced to electron-capture negative ion mass spectrometry (GC/ECNI-MS) are discussed. The environmental relevance and important mass spectrometric features of the compounds are described as well. Our database aims to support the closer inspection and identification of peaks in gas chromatograms and to initiate dedicated screening for less frequently studied organobromines in samples.
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Marine mammals from Queensland, Australia, are bioaccumulating elevated concentrations of a range of polybrominated natural products. In this study, we detected three new polybrominated dimethoxybiphenyls (PBDMBs) in the blubber of selected marine mammal samples which were identified as 2,6′-dimethoxy-3,3′,5-tribromobiphenyl (2,6′-diMeO-BB 36), 2,2′-dimethoxy-3,3′-dibromobiphenyl (2,2′-diMeO-BB 36), and 6,6′-dimethoxy-3,3′-dibromobiphenyl (6,6′-diMeO-BB 11). These three PBDMBs are structurally related to the known natural product 2,2′-dimethoxy-3,3′,5,5′-tetrabromobiphenyl (2,2′-diMeO-BB 80). In the first part of this study, 2,2′-diMeO-BB 80 was photochemically debrominated under UV irradiation. This resulted in seven of eight possible mono- to triBDMBs as debromination products. In the second part of this study, the structure of all PBDMBs debromination products was investigated. This was supported by synthesis of two diBDMB and one triBDMB via bromination and subsequent methylation of 2,2′-biphenyldiol. Structures of the remaining PBDMBs were tentatively assigned by considering the retention times, mass spectra and amounts formed during UV irradiation of 2,2′-diMeO-BB 80 . In the third part of this study, blubber of marine mammals from Australia was analysed for PBDMBs using gas chromatography in combination with electron ionization mass spectrometry (GC/EI-MS) in the selected ion monitoring mode. In these samples, 2,2′-diMeO-BB 80 was found at concentrations of 200-1800 ng g-1 lipid weight (lw). The latter represents the highest concentration reported for this compound in environmental samples. 6,6′-diMeO BB 11, 2,2′-diMeO BB 36, and 2,6′-diMeO BB 36 were present at ∼7 ng g-1 lipids, or 0.43-1.5% of diMeO-BB 80. No further PBDMBs were detected in the samples. The di- and triBDMBs identified in marine mammal blubber have not been reported as natural products. They may represent either new natural products or transformation products of 2,2′-diMeO-BB 80.
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1,2′- and 1,3′-Bipyrroles, which are attractive precursors for the synthesis of bipyrrole-based natural products, are synthesized in one-pot from 2- and 3-nitropyrroles by a sequential nitro group reduction—Paal–Knorr pyrrole synthesis.
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Thousands of halogenated natural products (HNPs) pervade the terrestrial and marine environment. HNPs are generated by biotic and abiotic processes and range in complexity from low molecular mass natural halocarbons (nHCs, mostly halomethanes and haloethanes) to compounds of higher molecular mass which often contain oxygen and/or nitrogen atoms in addition to halogens (hHNPs). nHCs have a key role in regulating tropospheric and stratospheric ozone, while some hHNPs bioaccumulate and have toxic properties similar those of anthropogenic persistent organic pollutants (CEACs). Both chemical classes have common sources: biosynthesis by marine bacteria, phytoplankton, macroalgae and some invertebrate animals, and both may be similarly impacted by alteration of production and transport pathways in a changing climate. The nHCs scientific community is advanced in investigating sources, atmospheric and oceanic transport, and forecasting climate change impacts through modeling. By contrast, these activities are nascent or non-existent for hHNPs. Goals of this paper are to: 1. Review production, sources, distribution and transport pathways of nHCs and hHNPs through water and air, pointing out areas of commonality. 2. By analogy to nHCs, argue that climate change may alter these factors for hHNPs. 3. Suggest steps to improve linkage between nHCs and hHNPs science to better understand and predict climate change impacts.
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Halogenated natural products (HNPs) are widespread compounds found at high concentrations in top predators such as seabirds. This paper reviews available data on methoxylated polybrominated diphenyl ethers (MeO-BDEs), heptachloro-1'-methyl-1,2'-bipyrrole (Q1) and 1,1'-dimethyl-2,2'-bipyrroles (HDBPs) in these animals. In all, 25 papers reported such HNPs in seabirds. White tailed sea eagle from Sweden was the seabird species with higher MeO-BDEs levels in eggs and blood, while in liver the European shag from Norway was the one. Regarding HDBPs, glaucous gull livers from North Water Polynya and Leach's storm petrel eggs from South Canada (NE Atlantic) showed the highest levels, while brown skua eggs presented the highest concentration of Q1. DBP-Br4Cl2 and DBP-Br6 were the most abundant HDBPs in seabirds, although only one study investigated DBP-Br6. Furthermore, 2'-MeO-BDE-68/6'-MeO-BDE-47 ratios were lower than one in mostly of the studies (91%). The main sources of methoxylated congeners found in seabirds might to be from sponges and/or associated organisms (bacteria). The scarcity of data in seabirds showed the gap in knowledge. Few studies were done especially in tropical areas and Southern Hemisphere and the most were conducted in the northwest part of the globe. This review arouses the need of knowledge about the distribution of these compounds in seabirds worldwide as well as it encourages toxicological studies to better understand the possible effects of HNPs on seabirds.
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Previously unknown halogenated compounds were detected during the analysis of halogenated flame retardants in two sediment cores collected from Lake Michigan. Gas chromatography coupled with high-resolution or low-resolution mass spectrometry (MS) was used to determine the chemical structures for a total of 15 novel polyhalogenated carbazoles (PHCs) with the general molecular formula C12H9-x-y-zNClxBryIz. Based on the mass spectra generated by electron impact (EI) and electron capture negative ionization (ECNI) MS, eight PHCs were tentatively identified as polybrominated carbazoles, while the others were mixed halogenated carbazoles containing in addition to bromine either chlorine or iodine or both. Patterns of halogen substitution of PHCs included Br2 to Br5, ClBr2, ClBr3, ClBr4, ClBr3I, Br4I and Br3I2. 3,6-Dibromocarbazole (3,6-DiBC) and 1,3,6,8-tetrabromocarbazole were also found among the PHCs. Profiles of concentration versus depth of sediment at the two sites showed various patterns among polybrominated carbazoles. The abundance of mixed halogenated carbazoles peaked at depths of 12 cm to 16 cm and remained at relatively constant levels in deeper sediment, but declined markedly in more recently deposited sediments. This is the first study discovering the seven mixed halogenated carbazoles in the environment. Detailed methods for their detection and identification are provided.
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A suite of eight polyhalogenated carbazole (PHCZ) congeners were detected in sediments of the Jiaozhou Bay wetland. 3,6-dichlorocarbazole (36-CCZ), and 3,6-dibromocarbazole (36-BCZ) were detected in all samples. The concentrations of ΣPHCZs ranged from 6.9 to 33.4 ng/g dry weight (dw). The recovery of surrogate standard ranged from 85 to 109%. Significant relationships were found between the concentrations of 36-CCZ and those of the other three detected compounds (36-BCZ, 36-ICZ, and 1368-BCZ). However, with regard to the other chemicals, only 1368-BCZ was related to 36-ICZ. The toxic equivalent (TEQ) was used to assess the relative toxicity of PHCZs, which ranged within 0.1-3.9 pg TEQ/g dw in sediment. The inventory of ΣPHCZs was 58.9 kg. These results indicate that PHCZs are widely distributed in the Jiaozhou wetland and the dyeing and finishing industries may be important contamination sources of PHCZs.
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Halogenated organic compounds (HOCs) in marine species collected from the Atlantic Ocean [3 shortfin mako (Isurus oxyrinchus) and 1 porbeagle (Lamna nasus)], and 12 sea turtles collected from the Pacific Ocean [3 loggerhead (Caretta caretta), 3 green (Chelonia mydas), 3 olive ridley (Lepidochelys olivacea), and 3 hawksbill (Eretmochelys imbricata)] were analyzed with a nontargeted analytical method using two-dimensional gas chromatography coupled to high-resolution time-of-flight mass spectrometry. Sharks and sea turtles had distinct HOC profiles. Halogenated methoxyphenols (halo-MeOPs) were the most abundant compound class identified in sea turtle livers, while polychlorinated biphenyls (PCBs) were the most abundant in shark livers. In addition to legacy contaminants and halo-MeOPs, a total of 110 nontargeted/novel HOCs (NHOCs) were observed in the shark livers. Shortfin mako collected from the northern Gulf of Mexico contained the largest number (89) and most diverse structural classes of NHOCs. Among all NHOCs, a group of compounds with the elemental composition C14H12–nCln (n = 5–8) exhibited the highest concentrations, followed by chlorocarbazoles and tris(chlorophenyl) methanes (TCPMs). Using nontargeted workflows, a variety of known and unknown HOCs were observed, which demonstrate the need to develop more complete chemical profiles in the marine environment.
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Amongst the more than 5,000 naturally occurring organohalogen compounds, both biotic and abiotic, are a diverse collection of structurally novel heterocycles. The present review covers this fascinating area of natural products as presented over the past three years.
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Development of catalytic hydrodehalogenation of halogenated organic compounds is an important topic from the viewpoint of environment protection. Herein, we conducted the first work on the utilization of a saturated aqueous solution of sodium acetate (CH3COONa) as an efficient and environmentally-friendly reaction medium for transfer hydrodehalogenation of various aryl halides using Pd/C as the catalyst. It was found that the transfer hydrodehalogenation could be accelerated significantly by the saturated CH3COONa aqueous solution due to the surfactant-similar effect of CH3COONa and the activation of the C-Cl bond by the dissolved solvated ions.
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Polyhalogenated N-methylbi- pyrroles of two different structure classes have been detected worldwide in over 100 environmental samples including seawater, bird eggs, fish, dolphin blubber, and in the breast milk of humans that consume seafood. These molecules are concentrated in the fatty tissues in comparable abundance to some of the most important anthropogenic contaminants, such as the halogenated flame-retardants and pesticides. Although the origin of these compounds is still unknown, we present evidence that the production of these materials can involve the direct ozone activated seawater halogenation of N-methylbipyrrole precursors. This observation shows that environmental polyhalogenated bipyrroles can be produced via an abiotic process, and implies that the ozone activated halogenation of a variety of natural and anthropogenic seawater organics may be a significant process occurring in surface ocean waters.
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Coastal reintroduction sites for California condors (Gymnogyps californianus) can lead to elevated halogenated organic compound (HOC) exposure and potential health impacts due to the consumption of scavenged marine mammals. Using nontargeted analysis based on comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC×GC/TOF-MS), we compared HOC profiles of plasma from inland and coastal scavenging California condors from the state of California (CA), and marine mammal blubber from CA and the Gulf of California off Baja California (BC), Mexico. We detected more HOCs in coastal condors (32 ± 5, mean number of HOCs ± SD, n = 7) than in inland condors (8 ± 1, n = 10) and in CA marine mammals (136 ± 87, n = 25) than in BC marine mammals (55 ± 46, n = 8). ∑DDT-related compounds, ∑PCBs, and total tris(chlorophenyl)methane (∑TCPM) were, respectively, ∼7, ∼3.5, and ∼148 times more abundant in CA than in BC marine mammals. The endocrine-disrupting potential of selected polychlorinated biphenyls (PCB) congeners, TCPM, and TCPMOH was determined by in vitro California condor estrogen receptor (ER) activation. The higher levels of HOCs in coastal condors compared to those in inland condors and lower levels of HOC contamination in Baja California marine mammals compared to those from the state of California are factors to consider in condor reintroduction efforts.
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This paper describes the application of a novel, practical approach for isolation of individual compounds from complex organic matrices for natural abundance radiocarbon measurement. This is achieved through the use of automated preparative capillary gas chromatography (PCGC) to separate and recover sufficient quantities of individual target compounds for (14)C analysis by accelerator mass spectrometry (AMS). We developed and tested this approach using a suite of samples (plant lipids, petroleums) whose ages spanned the (14)C time scale and which contained a variety of compound types (fatty acids, sterols, hydrocarbons). Comparison of individual compound and bulk radiocarbon signatures for the isotopically homogeneous samples studied revealed that Δ(14)C values generally agreed well (±10%). Background contamination was assessed at each stage of the isolation procedure, and incomplete solvent removal prior to combustion was the only significant source of additional carbon. Isotope fractionation was addressed through compound-specific stable carbon isotopic analyses. Fractionation of isotopes during isolation of individual compounds was minimal (<5‰ for δ(13)C), provided the entire peak was collected during PCGC. Trapping of partially coeluting peaks did cause errors, and these results highlight the importance of conducting stable carbon isotopic measurements of each trapped compound in concert with AMS for reliable radiocarbon measurements. The addition of carbon accompanying derivatization of functionalized compounds (e.g., fatty acids and sterols) prior to chromatographic separation represents a further source of potential error. This contribution can be removed using a simple isotopic mass balance approach. Based on these preliminary results, the PCGC-based approach holds promise for accurately determining (14)C ages on compounds specific to a given source within complex, heterogeneous samples.
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We estimated KOW values that are usually derived by liquid chromatography solely from gas chromatographic (GC) data by selective correlation with PCB congeners as secondary standards. The GC method was established and validated with literature-known values obtained with other methods. Twenty-seven chlorinated diphenyl ethers (PCDE), 19 chlorinated naphthalenes (PCN), 4,4'-DDE, and three brominated diphenyl ethers (PBDE) were used for method validation. The advantages of our method are that only amounts in the nanogram range or less are needed, complex mixtures can be analyzed, KOW values of isomers can be determined, and even the exact structure of compounds does not have to be known. The quality of the KOW values obtained by the GC method mainly depends on the accuracy of the data of the compounds used as standards for the correlation. These data should be based on reliable experimental methods. Our semi-experimental approach in approximating physicochemical data relevant to the environmental distribution--vapor pressure of subcooled liquid and log KOW--can be extended to further classes of compounds because normalized GC retention data are easily available. We exemplified our approach with a bioaccumulating naturally occurring heptachlorinated 1-methyl-1',2-bipyrrole, which is highly abundant in fish from the South Atlantic among others.
Chapter
The history of persistent, bioaccumulative, and toxic chemicals (PBTs) is traced in this chapter from the 1825 synthesis of technical "benzene hexachloride (BHC)" by Faraday to the current international efforts to phase out 12 "persistent, organic pollutants" (POPs) under the auspices of the United Nations Environmental Program (UNEP). In the 1930s, new uses were sought for chlorine, leading to the discovery of a number of chlorinated insecticidal chemicals, including DDT, which earned Müller the Nobel Prize in Medicine for its great success during and following the War to control typhus, malaria, typhoid fever, and cholera. Beginning in the 1960s, however, concerns were identified for the persistence, bioaccumulation, and food chain biomagnification of DDT and other PBTs, and their effects on reproduction in grebes, falcons, and eagles. In addition, these compounds were being detected in geographical locations far from their production and use. PBT properties are found not only in chlorinated pesticides including DDT, but also in halogenated industrial chemicals such as polychlorinated biphenyls. In addition, PBTs, including polychlorinated dibenzo-p-dioxins and dibenzofurans, arise as unintended products of industrial processes or combustion. Although, a large number of chlorinated and brominated compounds have been isolated from natural sources, including marine organisms, it is their production and widespread distribution by anthropogenic sources that is of concern.
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The global distribution of 22 potentially harmful organochlorine compounds was investigated in more than 200 tree bark samples from 90 sites worldwide. High concentrations of organochlorines were found not only in some developing countries but also in industrialized countries, which continue to be highly contaminated even though the use of many of these compounds is restricted. The distribution of relatively volatile organochlorine compounds (such as hexachlorobenzene) is dependent on latitude and demonstrates the global distillation effect, whereas less volatile organochlorine compounds (such as endosulfan) are not as effectively distilled and tend to remain in the region of use.
Article
Q1, a heptachloro component of unknown structure and origin, was recently identified as a major organochlorine contaminant in samples from Africa and the Antarctic. Gas chromatography in combination with low resolution mass spectrometry (LRMS) was applied to establish a molecular weight of m/z 384 including seven chlorine atoms. Three possible molecular formulae (C(11)H(7)Cl(7), C(10)H(3)Cl(7)O, and C(9)H(3)Cl(7)N(2)) were proposed which could not be distinguished by LRMS. In this presentation the molecular composition of Q1 was studied using gas chromatography in combination with high resolution electron impact ionization mass spectrometry. With the option of further heteroatoms (P, S, N, O, F, and Br), 17 molecular formulae were obtained for the molecular weight of 384 u. In the selected ion monitoring (SIM) mode, performed with a resolution of 16,000, highest response was found at 383.812 or C(9)H(3)Cl(7)N(2). 11 fragment ions detected in the low resolution full scan mass spectrum of Q1 were also investigated in the high resolution SIM mode. In every case, the nitrogen-variant showed highest abundance while the other 16 structural variants could be definitely excluded. These investigations revealed that the molecular formula of Q1 is C(9)H(3)Cl(7)N(2). No stable component with this molecular formula has ever been reported in the literature, to our knowledge. Copyright 1999 John Wiley & Sons, Ltd.
Article
Literature search of the knowledge on the degradation of persistent organic pollutants (POPs) in environmental compartments air, water, soil and sediment was done in purpose to find properties of POPs of interest for modeling. One degradation process, hydrolysis (chemical degradation), was omitted as negligibly slow for POPs studied. The other two, photolysis and biodegradation processes, were considered separately in purpose to develop estimation procedures. The estimates can be given as pseudo first-order rate constants kP for photolysis and kB for biodegradation. For each compartment, an overall degradation rate is k(tot) = kP + kB and lifetime t(1/2) = ln 2/k(tot). The latter values, lifetimes in each compartment, will be used as input parameters to the Baltic Sea model.
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Two new minor tribromodibenzo-p-dioxins, spongiadioxin C (1) and its methyl ether (2), were isolated from an Australian marine sponge Dysidea dendyi, together with the known minor metabolites methyl ethers of spongiadioxins A (4) and B (6) and polybrominated diphenyl ethers (7-9). The structures of the new compounds were established by 1D and 2D NMR spectroscopy and confirmed by synthesis of 2 from diphenyl ether 9. All isolated compounds inhibited the cell division of fertilized sea urchin eggs.
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The long-range transport of persistent organic pollutants (POPs) is investigated with two multimedia box models of the global system. ChemRange is a purely evaluative, one-dimensional steady-state (level III) model; CliMoChem is a two-dimensional model with different temperatures, land/water ratios and vegetation types in different latitudinal zones. Model results are presented for three case studies: (i) the effect of atmospheric aerosol particles on the long-range transport of POPs, (ii) the effect of oceanic deposition on the long-range transport of different PCB congeners, (iii) the global fractionation of different PCB congeners. The model results for these case studies show: (i) the low atmospheric half-lives estimated for several organochlorine pesticides are likely to be inconsistent with the observed long-range transport of these compounds; (ii) export to the deep sea reduces the potential for long-range transport of highly hydrophobic compounds (but does not remove these chemicals from the biosphere); (iii) there are different meanings of the term global fractionation that refer to different aspects of the fractionation process and need to be distinguished. The case-study results further indicate that the influences of varying environmental conditions on the physicochemical properties and the degradation rate constants of POPs need to be determined.
Article
Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in many types of consumer products. Perhaps as a result of their widespread use and their lipophilicity, these compounds have become ubiquitous in the environment and in people. This review summarizes PBDE concentrations measured in several environmental media and analyzes these data in terms of relative concentrations, concentration trends, and congener profiles. In human blood, milk, and tissues, total PBDE levels have increased exponentially by a factor of similar to100 during the last 30 yr; this is a doubling time of similar to5 yr. The current PBDE concentrations in people from Europe are similar to2 ng/g lipid, but the concentrations in people from the United States are much higher at similar to35 ng/g lipid. Current PBDE concentrations in marine mammals from the Canadian Arctic are very low at similar to5 ng/g lipid, but they have increased exponentially with a doubling time of similar to7 yr. Marine mammals from the rest of the world have current PBDE levels of similar to1000 ng/g lipid, and these concentrations have also increased exponentially with a doubling time of similar to5 yr. Some birds' eggs from Sweden are also highly contaminated (at similar to2000 ng/g lipid) and show PBDE doubling times of similar to6 yr. Herring gull eggs from the Great Lakes region now have PBDE concentrations of similar to7000 ng/g lipid, and these levels have doubled every similar to3 yr. Fish from Europe have similar to10 times lower PBDE concentrations than fish from North America. From these and other data, it is clear that the environment and people from North America are very much more contaminated with PBDEs as compared to Europe and that these PBDE levels have doubled every 4-6 yr. Analyses of the relative distributions of the most abundant PBDE congeners (using category averages and principal component analysis) indicated that these patterns cannot yet be used to assign sources to these pollutants.
Article
Concentrations of four naturally produced halogenated dimethyl bipyrroles (HDBPs) were quantitated in marine fish (n = 10), freshwater fish (n = 10), canned fish (n = 10), and shrimp composites (n = 10) collected from 1992 to 2002 for the Canadian Total Diet Study. Canned fish composites composed of epipelagic higher trophic level species contained the highest concentration of HDBPs (SigmaHDBP geometric mean +/- standard error = 880 +/- 690 pg/g of wet weight, n = 10), which was significantly higher than that found in the other three composites. There were no significant temporal trends of HDBP concentrations observed for any of the four composites. The estimated daily intake of HDBPs via consumption of fish and seafood was determined to be 53 pg/kg of body mass/day and 0.10 pg of TEQ/kg of body mass/day when transformed to 2,3,7,8-tetrachlorodibenzodioxin equivalents (TEQs). In the canned fish and shrimp composites collected in 1998, HDBPs accounted for approximately 98 and 19%, respectively, of the total quantitated TEQ (which included polychlorinated biphenyls, dioxins, and furans). The results of this study provide the first estimate of human exposure to naturally produced bioaccumulating organohalogens.
Article
Q1, an organochlorine component with the molecular formula C(9)H(3)Cl(7)N(2) and of unknown origin was recently identified in seal blubber samples from the Namibian coast (southwest of Africa) and the Antarctic. In these samples, Q1 was more abundant than PCBs and on the level of DDT residues. Furthermore, Q1 was more abundant in seals from the Antarctic than the Arctic. To prove this assumption, gas chromatography-electron-capture negative ion mass spectrometry (GC/ECNI-MS), which is sensitive and selective for Q1, allowed for screening of traces of Q1 even in samples with particularly high levels of other organochlorine contaminants. Q1 was isolated by high-performance liquid chromatography (HPLC) from a skua liver sample. A 1:1 mixture with trans-nonachlor in electron-capture detectors (ECDs) was used to determine the relative response factor with ECNI-MS. The ECNI-MS response of Q1 turned out to be 4.5 times higher than that of trans-nonachlor in an ECD. With GC/ECNI-MS in the selected ion-monitoring mode, four Antarctic and four Arctic air samples were investigated for the presence of Q1. In the Antarctic air samples, Q1 levels ranged from 0.7 to 0.9 fg/m(3). In Arctic air samples, however, Q1 was below the detection limit (<0.06 fg/m(3) or 60 ag/m(3)). We also report on high Q1 levels in selected human milk samples (12-230 microg/kg lipid) and, therefore, suggested that the unknown Q1 is an environmental compound whose origin and distribution should be investigated in detail. Our data confirm that Q1 is a bioaccumulative natural organochlorine product. Detection of a highly chlorinated natural organochlorine compound in air and human milk is novel.
Article
Halogenated organic compounds (HOCs) such as 1,1'-dimethyl-3,3',4,4'-tetrabromo-5,5'-dichloro-2,2'-bipyrrole (DBP-Br4Cl2) and heptachloro-1'-methyl-1,2'-bipyrrole (Q1) have been detected worldwide, sometimes at high levels in Antarctic air, seabird eggs, the blubber of marine mammals, and, most notably, even human milk. To date, it has been difficult to determine whether these compounds are natural products or derived from industrial synthesis. Molecular-level 14C analysis of these compounds is particularly appealing because most industrial compounds are manufactured from petrochemicals (14C-free) and natural compounds should have "modern" or "contemporary" 14C levels. To investigate the source of DBP-Br4Cl2, we isolated 600 microg of this compound (150 microg of carbon) from marine animal extracts by employing gel permeation chromatography, Florisil column chromatography, and two-dimensional preparative capillary gas chromatography. The purified DBP-Br4Cl2 was split into two samples (75 microg of carbon each) and analyzed by accelerator mass spectrometry for 14C content. The delta14C values were -449 percent per thousand and -467 percent per thousand, corresponding to conventional 14C ages of 4740 and 5000 years before present (BP), respectively. The presence of detectable 14C in the DBP-Br4Cl2 strongly points to at least a natural or biogenic source. However, these delta14C values for DBP-Br4Cl2 are more depleted than expected for a recently synthesized natural product. Several explanations are discussed, but additional samples
Article
Recent studies of arctic marine food webs have provided detailed insights regarding the biological and chemical factors that influence the bioaccumulation and trophic transfer of persistent organochlorine (OC) contaminants in aquatic systems. The present paper summarizes the recent literature with an emphasis on identifying important ecological factors for explaining variability of OC concentrations among organisms. The Arctic ecosystem has a number of unique attributes, including long food chains, reduced diversity of species, similar food webs across the entire region, and limited influence from pollution point sources. Lipid content, body size, age, gender, reproduction, habitat use, migration, biotransformation, seasonal changes in habitat conditions, feeding ecology, and trophic position have all been demonstrated to influence OC concentrations and bioaccumulation in arctic marine biota. The relative importance of each factor varies among OCs and organisms. Diet or trophic level is the dominant factor influencing OC concentrations and dynamics in seabirds and marine mammals, although biotransformation can significantly influence nonrecalcitrant OCs, such as hexachlorocyclohexane isomers. Dietary accumulation of OCs is also an important route of exposure for arctic fish and zooplankton, and biomagnification of OCs may also occur among these organisms. To date, only limited attempts have been made to model trophic transfer of OCs in the arctic marine food web. Although models developed to assess OC dynamics in aquatic food webs have included some biological variables (e.g., lipid content, feeding rate, diet composition, and growth rate), selection of processes included in these models as well as their mathematical solutions and parameterization all introduce simplification. This reduces biological validity of the models and may be particularly problematic in a highly seasonal environment, such as the Arctic Ocean.
Article
Chromophoric or colored dissolved organic matter (CDOM) is one of the principal light adsorbing components of seawater, particularly in the ultraviolet, where it attenuates over 90% of downwelling ultraviolet radiation. In highly productive coastal regions and throughout most of the global ocean, in situ biological production is the major source of CDOM. However, little is known about CDOM composition on the molecular level, and there are only a few reports that link CDOM composition to autochthonous biological sources. Here we report the isolation and characterization of CDOM components from one coastal and two open-ocean sites. Each sample contains a complex mixture of light absorbing (300-400 nm) components, including 2,4-dichlorobenzoic acid and a suite of novel, polychlorinated biphenyl carboxylic acids that closely resemble polychlorinated biphenyls (PCBs) of anthropogenic origin. However, the global inventory and isomer distribution of dissolved chlorinated aromatic acids suggest they are derived from in situ biological production rather than anthropogenic contaminants. These novel chlorinated aromatic acids account for a significant amount of CDOM adsorption in the ultraviolet.
Article
Methoxylated polybrominated diphenyl ethers (MeO-PBDEs) have been found bioaccumulated in the tissues of a variety of aquatic animals and at concentrations comparable to those of anthropogenic halogenated organic compounds, including polychlorinated biphenyls (PCBs). The origin of the MeO-PBDEs has been uncertain; circumstantial evidence supports a natural and/or an industrial source. By analyzing the natural abundance radiocarbon content of two MeO-PBDEs isolated from a True's beaked whale (Mesoplodon mirus), we show that these compounds were naturally produced.
Article
Polybrominated dibenzo-p-dioxins (PBDDs) are known to be formed as byproducts in connection with the manufacture and combustion of products containing brominated flame retardants. However, to date little is known about the occurrence of PBDDs in biological samples. The aim of the present investigation was to examine the presence of PBDDs in blue mussels (Mytilus edulis) from the Baltic Sea employing a procedure adapted for dioxin analysis. Two triBDDs (1,3,7-triBDD and 1,3,8-triBDD) were identified in biota here for the first time. This identification was based on accurate mass determination and comparison of retention times on three gas chromatographic columns of different polarities (PTE 5, SP-2331, and OV1701/heptakis) with synthesized standards, together with comparisons of electron capture negative ionization (ECNI) and electron ionization (EI) mass spectra. In addition, five PBDDs and one polybrominated dibenzofuran (PBDF) were tentatively identified; altogether, one diBDD, three triBDDs, three tetraBDDs, and one triBDFwere detected in the blue mussels. To our knowledge this is the first time PBDDs have been identified in biota of the Baltic Sea. The sigma triBDD concentration in the blue mussels was estimated to be 170 ng/g lipids. The origin of these PBDDs remains unclear, but a plausible hypothesis could be biogenic formation in the marine environment.
Article
Bioaccumulation of persistent organic compounds can eventually lead to concentrations in wildlife and humans that are deleterious to health. The present paper documents the identification, quantification, and synthesis of a novel compound, 2,2'-dimethoxy-3,3',5,5'-tetrabromobiphenyl (2,2'-diMeO-BB80), present in the marine mammals Striped dolphin (Stenella coeruleoalba), Bottlenose dolphin (Tursiops truncatus), Minke whale (Balaenoptera acutorostrata), and Baird's beaked whale (Berardius bairdii) caught in the Pacific Ocean. Identification was based on comparison of the relative retention times of the compound on two gas chromatographic columns of different polarities to those of an authentic standard. Furthermore, this identification was also supported by comparison of the full scan mass spectrometric data collected employing electron ionization (El), positive ion chemical ionization (PICI), and electron capture negative ionization (ECNI). The concentrations of 2,2'-diMeO-BB80 in the samples ranged from 12 to 800 ng/g lipid, making this consistently one of the most abundant compounds among those analyzed, including polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCDD), and methoxylated PBDEs. The known occurrence of 3,3',5,5'-tetrabromo-2,2'-biphenyldiol (2,2'-diOH-BB80) in the marine environment as a natural product suggests that its methylated derivative, 2,2'-diMeO-BB80, is also of natural origin. To obtain the necessary authentic standards, synthesis was performed of 2,2'-diMeO-BB80 and the known natural product 2',6-dimethoxy-2,3',4,5'-tetrabromodiphenyl ether (2',6-diMeO-BDE68).
Article
During the analysis of brominated flame retardants in sediment cores taken from Lake Michigan, a group of unknown brominated compounds were observed. To identify their chemical structures, a variety of gas chromatographic mass spectrometric techniques were used. With the help of high-resolution and positive chemical ionization mass spectrometry, the molecular formula of the most abundant congener was established to be C12H5Br4N. On the basis of the electron impact and electron capture negative ionization mass spectra, this chemical was suspected of being a tetrabromocarbazole. The structure was confirmed by comparing the mass spectra and gas chromatographic retention times of an authentic standard of 1,3,6,8-tetrabromocarbazole with those of the most abundant unknown. The other unknown compounds may be other bromocarbazole congeners. The time trend determined by measuring these compounds as a function of depth in the Lake Michigan sediment cores indicated that the concentration of 1,3,6,8-tetrabromocarbazole peaked around 1920-1935. This is the first time that bromocarbazoles have been found in the environment.
Article
Three 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 gas chromatography mass spectrometry (GCMS) and appear to be highly brominated analogues of Q1, a heptachlorinated HOC suspected to be naturally produced. These 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 microg/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.
A new tetrabromodiphenyl ether from the sponge Dysidea herbacea of the Indian Ocean Biological and chemical importance in the bioaccumulation and trophic transfer of persis-tent organochlorine contaminants in arctic marine food webs
  • V Anjaneyulu
  • K Nageswara Rao
  • P Radhika
  • M Muralikrishna
  • J D Connolly
Anjaneyulu, V., Nageswara Rao, K., Radhika, P., Muralikrishna, M., Connolly, J.D., 1996. A new tetrabromodiphenyl ether from the sponge Dysidea herbacea of the Indian Ocean. Indian J. Chem. 35B, 89e90. Borgå, K., Fisk, A.T., Hoekstra, P.F., Muir, D.C.G., 2004. Biological and chemical importance in the bioaccumulation and trophic transfer of persis-tent organochlorine contaminants in arctic marine food webs. Environ. Toxicol. Chem. 23, 2367e2385.
High-resolution gas chromatography data as basis for the estimation of Kow values using PCB congeners as secondary standards
  • Hackenburg