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  • 51.
    Linderoth, Maria
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Ledesma, Maria
    Zebühr, Yngve
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Balk, Lennart
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Sex steroids in the female zebrafish (Danio rerio). Effects of cyproterone acetate and leachate-contaminated sediment extract2006In: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 79, no 2, p. 192-200Article in journal (Refereed)
    Abstract [en]

    In Molnbyggen, a leachate-contaminated lake in Sweden, effects on the reproductive system of perch included a decreased frequency of sexually mature female perch, reduced gonadosomatic index and decreased plasma levels of androstenedione and testosterone, but the contaminants responsible for these effects have not yet been identified. A biomarker-directed fractionation approach could be used to narrow the search for the compound(s) responsible for the adverse effects in Molnbyggen female perch. Thus, it is important to develop and test a suitable biomarker, which can be used in this type of approach. We evaluated if decreased concentrations of sex steroids could work as an in vivo end-point in female zebrafish fed an organic extract of bottom sediments from Molnbyggen. The responsiveness of zebrafish to endocrine alteration was evaluated using a positive control substance, cyproterone acetate (CA), which is known to inhibit steroid biosynthesis. After the 21-day exposure period the concentrations of testosterone (T) and estradiol (E2) were successfully determined by HRGC/HRMS in whole-body homogenates of individual fish. Median T concentrations were 1.7 pmol/g fish in controls and were decreased after exposure both to CA (0.55 pmol/g fish) and Molnbyggen sediment extract (1.2–1.3 pmol/g fish). Median E2 concentrations were 5.3 pmol/g fish in controls and were decreased after CA exposure (2.3 pmol/g fish) and after exposure to Molnbyggen sediment extract (4.0–4.5 pmol/g fish). This suggests that sex steroid concentrations in zebrafish are responsive to endocrine alteration and indicates that compounds with endocrine altering potency are present in Molnbyggen sediments.

  • 52. Lundstedt-Enkel, Katrin
    et al.
    Bjerselius, Rickard
    Asplund, Lillemor
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Nylund, Kerstin
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Liu, Yang
    Södervall, Mathias
    Modeling Relationships between Baltic Sea Herring (Clupea harengus) Biology and Contaminant Concentrations Using Multivariate Data Analysis2010In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 44, no 23, p. 9018-9023Article in journal (Refereed)
    Abstract [en]

    Baltic Sea herring (Clupea harengus) is a pelagic, zoo-planktivorous fish and young (2-5 years old) individuals of this species are sampled annually in the Swedish marine monitoring program. This study determined concentrations of organochlorines (OCs) and brominated flame retardants (BFRs) in dorsal muscle from herring (n = 60) of varying age (2-13 years), weight (25-200 g), and body length (16-29 cm) caught at three locations in the Swedish part of the Baltic Proper. In order to ensure that the fish biclogy was as varied as possible, though still similar from all sampling sites, the fish to be chemically analyzed were selected from a large number of fish with determined biology using Multivariate Design. In statistical evaluation of the data, univariate and multivariate data analysis techniques, e.g. principal components analysis (PCA), partial least-squares regression (PLS), and orthogonal PLS (OPLS), were used. The results showed that the fish are exposed to a cocktail of contaminants and levels are presented. Significant OPLS models were found for all biological variables versus concentrations of OCs and BFRs, showing that fish biology covaries with fish contaminant concentrations. Correlation coefficients were as high as 0.98 for e.g. beta HCH concentration (wet weight) versus the lipid content. Lastly, the DC concentrations in herring muscle were modeled against the BFR concentrations to determine whether concentrations of either could be used to predict the other. It was found that OPLS models allowed BFR concentrations to be predicted from OC concentrations with high, but varying, accuracy (R-2 Ys between 0.93 to 0.75). Thus, fish biology and contaminant concentrations are interwoven, and fish biological parameters can be used to calculate (predict) contaminant concentrations. It is also possible to predict the BFR concentrations in an individual fish from its concentrations of OCs with very high accuracy.

  • 53.
    Löfstrand, K
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Malmvärn, A
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Bergman, Åke
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Asplund, L
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Trends and exposure of OH-PBDEs, MeO-PBDEs and PBDEs in baltic BIOTA2010In: Organohalogen Compounds, 2010Conference paper (Other academic)
  • 54.
    Löfstrand, Karin
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Haglund, Peter
    Umeå universitet, Kemiska institutionen.
    Bergman, Åke
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Kautsky, Lena
    Stockholm University, Faculty of Science, Department of Botany.
    Asplund, Lillemor
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Hydroxylated and methoxylated polybrominated diphenyl ethers and polybrominated dibenzo-p-dioxins in algae and blue mussels from the Swedish coast line - patterns and correlationsManuscript (preprint) (Other academic)
  • 55.
    Löfstrand, Karin
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Liu, Xitao
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM). Beijing Normal University, PR China.
    Lindqvist, Dennis
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Jensen, Sören
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Asplund, Lillemor
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Seasonal variations of hydroxylated and methoxylated brominated diphenyl ethers in blue mussels from the Baltic Sea2011In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 84, no 4, p. 527-532Article in journal (Refereed)
    Abstract [en]

    Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) and methoxylated polybrominated diphenyl ethers (MeO-PBDEs) found at high levels in the Baltic biota are mainly natural products, but can also be formed through metabolism or abiotic oxidation of polybrominated diphenyl ethers (PBDEs). The formation of OH-PBDEs is of concern since there is growing evidence of phenolic toxicity. This study investigates seasonal variations in levels of OH-PBDEs and MeO-PBDEs, focusing on an exposed species, the blue mussel (Mytilus edulis), sampled in the Baltic Sea in May, June, August and October of 2008. Both the OH-PBDE and MeO-PBDE levels in the mussels showed seasonal variations from May to October, the highest concentration of each congener appearing in June. The seasonal variation was more marked for OH-PBDEs than in MeO-PBDEs, but all congeners showed the same trends, except 6-MeO-BDE47 and 2′-MeO-BDE68, which did not significantly decline in concentrations after June. Biotic or abiotic debromination is suggested as a possible reason for the rapid decrease in methoxylated penta- and hexa-BDE concentrations observed in blue mussels from June to August, while the tetraBDE concentrations were stable. In addition, 1,3,7/1,3,8-tribrominated dibenzo-p-dioxins showed the same seasonal variation. The seasonal variations indicates natural formation and are unlikely to be due to transformation of anthropogenic precursors. The levels of PBDEs were fairly constant over time and considerably lower than those of the OH-PBDEs and MeO-PBDEs. The timing of the peaks in concentrations suggests that filamentous macro-algae may be important sources of these compounds found in the blue mussels from this Baltic Sea location.

  • 56.
    Löfstrand, Karin
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Malmvärn, Anna
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Haglund, Peter
    Umeå Universitet, Kemiska institutionen.
    Bignert, Anders
    Naturhistoriska riksmuseet, Miljögiftsforskning.
    Bergman, Åke
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Asplund, Lillemor
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Brominated phenols, anisoles, and dioxins present in blue mussels from the Swedish coastline2010In: Environmental Science and Pollution Research, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 17, no 8, p. 1460-1468Article in journal (Refereed)
    Abstract [en]

    Introduction  

    Naturally occurring hydroxylated polybrominated diphenyl ethers (OH-PBDEs), their methoxylated counterparts (MeO-PBDEs), and polybrominated dibenzo-p-dioxins (PBDDs), together with their potential precursors polybrominated phenols (PBPs) and polybrominated anisoles (PBAs), were analyzed in blue mussels (Mytilus edulis) gathered along the east coast (bordering the Baltic Sea) and west coast of Sweden (bordering the North Sea). Brown algae (Dictyosiphon foenicolaceus) and cyanobacteria (Nodularia spumigena) from the Baltic Sea, considered to be among the primary producers of these compounds, were also analyzed for comparison.

    Materials and methods  

    The samples were liquid–liquid extracted, separated into a phenolic and a neutral fraction, and subsequently analyzed by gas chromatography–mass spectrometry (GS-MS).

    Results and discussion  

    The levels of OH-PBDEs, MeO-PBDEs and PBDDs were significantly higher in Baltic Sea mussels than in those from the west coast, whereas the levels of PBPs and PBAs displayed the opposite pattern. The blue mussels from the Baltic Sea contained high levels of all analyzed substances, much higher than the levels of, e.g., polybrominated diphenyl ethers. In addition, the GC-MS chromatogram of the phenolic fraction of the west coast samples was dominated by four unknown peak clusters, three of which were tentatively identified as dihydroxy-PBDEs and the other as a hydroxylated-methyl-tetraBDE.

    Conclusions  

    Clearly, all of the compounds analyzed are natural products, both in the Baltic and the North Sea. However, the geographical differences in composition may indicate different origin, e.g., due to differences in the occurrence and/or abundance of various algae species along these two coasts or possibly a more extensive dilution on the west coast.

  • 57.
    MacInnis, Gordia
    et al.
    Environment Canada, Burlington, Canada.
    Letcher, Robert
    Environment Canada, National Wildlife Research Centre, Carleton University, Ottawa, Canada.
    McKinney, Melissa
    Environment Canada, National Wildlife Research Centre, Carleton University, Ottawa, Canada.
    Tomy, Gregg T.
    Fisheries & Oceans Canada, Winnipeg, Canada.
    Fång, Johan
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Bergman, Åke
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Marvin, Chris H.
    Environment Canada, Burlington, Canada.
    In vitro bioassay of racemic α- and γ-HBCD using liver microsomes from top trophic level Arctic marine mammals: enantiomeric-specific depletion and formation of hydroxylated HBCD metabolites2010In:  , 2010Conference paper (Other academic)
  • 58. MacInnis, Gordia
    et al.
    Letcher, Robert
    McKinney, Melissa
    Tomy, Gregg T.
    Lebeuf, M.
    Fång, Johan
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Bergman, Åke
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Marvin, Chris H.
    Investigation of HBCD metabolism in marine mammals from Canada using a hapatic micrsomal in vitro bioassay approach and comparison with field samples2010Conference paper (Other academic)
  • 59. Montano, Mauricio
    et al.
    Cocco, Emmanuelle
    Guignard, Cedric
    Marsh, Göran
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Hoffmann, Lucien
    Bergman, Åke
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Gutleb, Arno Christian
    Murk, Albertinka Jacoba
    New Approaches to Assess the Transthyretin Binding Capacity of Bioactivated Thyroid Hormone Disruptors2012In: Toxicological Sciences, ISSN 1096-6080, E-ISSN 1096-0929, Vol. 130, no 1, p. 94-105Article in journal (Refereed)
    Abstract [en]

    Polychlorinated biphenyls (PCBs) and polybrominated diphenyl-ethers (PBDEs) are metabolized into hydroxylated metabolites (OH-PCBs/PBDEs), which can disrupt the thyroid hormone homeostasis. Binding of these metabolites to transport proteins such as transthyretin (TTR) is an important mechanism of their toxicity. Several methods to quantify the competitive thyroxine (T-4) displacement potency of pure metabolites exist. However, quantification of the potency of in vitro metabolized PCBs and PBDEs has drawbacks related to the coextraction of compounds disturbing the T-4-TTR competitive binding assay. This study identifies and quantifies the major coextractants namely cholesterol, saturated and nonsaturated fatty acids (SFA and NSFA) at levels above 20 nmol per mg equivalent protein following various extraction methods. Their TTR binding potency was analyzed in a downscaled, nonradioactive fluorescence displacement assay. At concentration factors needed for TTR competitive binding, at least 10M of these coextracts is present, whereas individual SFA and NSFA disturb the assay from 0.3M. The effectiveness of the in vitro metabolism and extraction of the model compounds CB 77 and BDE 47 was chemically quantified with a newly developed chromatographic method analyzing silylated derivatives of the OH-metabolites and coextractants. A new method to selectively extract metabolites and limit coextraction of disturbing compounds to less than 5 nmol per mg equivalent protein is presented. It is now possible to make a dose-response curve up to 50% inhibition with bioactivated CB 77 and BDE 47. The toxic potencies of bioactivated persistent organic pollutants (POPs) should be taken into account to prevent serious underestimation of their hazard and risk.

  • 60.
    Motwani, Hitesh
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Shimakoshi, Hisashi
    Department of Chemistry and Biochemistry, Kyushu University.
    Golding, Bernard
    School of Chemistry, Newcastle University.
    Törnqvist, Margareta
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Hisaeda, Yoshio
    Department of Chemistry and Biochemistry, Kyushu University.
    Formation of an alkylcobyrinate from sucralose and mechanistic aspects of its Co-C bond cleavagesIn: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948Article in journal (Other academic)
  • 61.
    Motwani, Hitesh
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Törnqvist, Margareta
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Cob(I)alamin for measuring interspecies variation in butadiene epoxide metabolism in S9 liver fractions and evaluation of in vivo doses estimated from enzyme kinetics and from hemoglobin adductsIn: Toxicology and Applied Pharmacology, ISSN 0041-008X, E-ISSN 1096-0333Article in journal (Other academic)
  • 62.
    Motwani, Hitesh
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Törnqvist, Margareta
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    In vivo doses of butadiene epoxides as estimated from in vitro enzyme kinetics by using cob(I)alamin and measured hemoglobin adducts: An inter-species extrapolation approach2014In: Toxicology and Applied Pharmacology, ISSN 0041-008X, E-ISSN 1096-0333, Vol. 281, no 3, p. 276-284Article in journal (Refereed)
    Abstract [en]

    1,3-Butadiene (BD) is a rodent and human carcinogen. In the cancer tests, mice have been much more susceptible than rats with regard to BD-induced carcinogenicity. The species-differences are dependent on metabolic formation/disappearance of the genotoxic BD epoxy-metabolites that lead to variations in the respective in vivo doses, i.e. "area under the concentration-time curve" (AUC). Differences in AUC of the most gentoxic BD epoxy-metabolite, diepoxybutane (DEB), are considered important with regard to cancer susceptibility. The present work describes: the application of cob(I)alamin for accurate measurements of in vitro enzyme kinetic parameters associated with BD epoxy-metabolites in human, mouse and rat; the use of published data on hemoglobin (Hb) adduct levels of BD epoxides from BD exposure studies on the three species to calculate the corresponding AUCs in blood; and a parallelogram approach for extrapolation of AUC of DEB based on the in vitro metabolism studies and adduct data from in vivo measurements. The predicted value of AUC of DEB for humans from the parallelogram approach was 0.078 nM . h for 1 ppm . h of BD exposure compared to 0.023 nM . h/ppm . h as calculated from Hb adduct levels observed in occupational exposure. The corresponding values in nM . h/ppm . h were for mice 41 vs. 38 and for rats 126 vs. 137 from the parallelogram approach vs. experimental exposures, respectively, showing a good agreement This quantitative inter-species extrapolation approach will be further explored for the clarification of metabolic rates/pharmacokinetics and the AUC of other genotoxic electrophilic compounds/metabolites, and has a potential to reduce and refine animal experiments.

  • 63.
    Motwani, Hitesh
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Törnqvist, Margareta
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Quantitative analysis by liquid chromatography-tandem mass spectrometry of glycidamide using cob(I)alamin trapping method: Validation and application to in vitro metabolism of acrylamideIn: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778Article in journal (Other academic)
  • 64.
    Motwani, Hitesh V.
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Qiu, Shiran
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Golding, Bernard T.
    Kylin, Henrik
    Törnqvist, Margareta
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Cob(I)alamin reacts with sucralose to afford an alkylcobalamin: Relevance to in vivo cobalamin and sucralose interaction2011In: Food and Chemical Toxicology, ISSN 0278-6915, E-ISSN 1873-6351, Vol. 49, no 4, p. 750-757Article in journal (Refereed)
    Abstract [en]

    Vitamin B(12), viz., cyano- or hydroxo-cobalamin, can be chemically or enzymatically converted into the derivatives methyl- and adenosyl-cobalamin, which are complex organometallic cofactors associated with several cobalamin-dependent enzymes. The reduced form of vitamin B(12), cob(I)alamin {Cbl(I)}, obtained by reduction of hydroxocobalamin (OH-Cbl) with e.g. sodium borohydride, is one of the most powerful nucleophiles known. Cbl(I) was shown to react readily with the synthetic sweetener sucralose (1,6-dichloro-1,6-dideoxy-β-d-fructofuranosyl-4-chloro-4-deoxy-α-d-galactopyranoside) in an aqueous system to form an alkylcobalamin (Suc-Cbl). This occurred by replacement of one of the three chlorine atoms of sucralose with a cobalamin moiety. The efficiency of trapping sucralose in presence of excess Cbl(I) was estimated to be >90%. Furthermore, in an in vitro study using human liver S9 with NADPH regeneration, in presence of OH-Cbl and sucralose, Suc-Cbl was shown to be formed. The Suc-Cbl was characterized primarily by LC-ESI(+)-MS/MS. Given the human consumption of sucralose from food and beverages, such a reaction between the sweetener and reduced vitamin B(12) could occur in vivo.

  • 65. Motwani, Hitesh V.
    et al.
    Törnqvist, Margareta
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Quantitative analysis by liquid chromatography-tandem mass spectrometry of glycidamide using the cob(I)alamin trapping method: Validation and application to in vitro metabolism of acrylamide2011In: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1218, no 28, p. 4389-4394Article in journal (Refereed)
    Abstract [en]

    Glycidamide (GA) is the epoxy metabolite of acrylamide (AA). A sensitive analytical method for quantitative measurement of GA from in vitro metabolism studies is useful in several contexts, e.g. in studies of enzyme kinetics in different species and factors influencing the metabolism of AA to GA. It is however difficult to analyse compounds like GA, mainly due to their inherent reactivity. In the present study cob(I)alamin {Cbl(I)}, a reduced form of vitamin B(12), was used for trapping of GA. Cbl(I) can react with electrophilic species, such as an epoxide, 10(5) times faster than standard nucleophiles. The trapping of GA by Cbl(I) results in the formation of an alkylcobalamin (GA-Cbl) that was used for quantitative analysis of the epoxide. The alkylcobalamin was analysed by LC-MS/MS using an electrospray ionization source in the positive ion mode. The Cbl(I) method was validated for measurement of GA in liver S9 fractions from human and rat. GA levels down to 0.01 mu M were measured in the S9 fractions, providing a sensitivity that was ca. 100 times higher than that earlier estimated by the Cbl(I) method for measurement of other (e.g. butadiene) epoxides. Compared to current analytical methods for measurement of GA, the Cbl(I) method was 10-100 times more sensitive. The method was applied to quantify GA formed from the metabolism of AA in liver S9 from human and rat.

  • 66.
    Norrgran, J
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Bergman, Åke
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Jones, Bernt
    Lindquist, N-G
    Polybrominated diphenyl ethers and their metabolites, a potential cause for the development of the endocrine disorder hyperthyroidism in cats2010In: Organohalogen Compounds, 2010Conference paper (Other academic)
  • 67.
    Norrgran, Jessica
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Jones, Bernt
    Lindquist, Nils-Gunnar
    Bergman, Åke
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Decabromobiphenyl, Polybrominated Diphenyl Ethers, and Brominated Phenolic Compounds in Serum of Cats Diagnosed With the Endocrine Disease Feline Hyperthyroidism2012In: Archives of Environmental Contamination and Toxicology, ISSN 0090-4341, E-ISSN 1432-0703, Vol. 63, no 1, p. 161-168Article in journal (Refereed)
    Abstract [en]

    The incidence of cats being diagnosed with feline hyperthyroidism (FH) has increased greatly since it was first described in 1979. The cause of FH has not been established. Hypothetically, there is a link between increasing FH and exposure to brominated flame retardants. Much greater polybrominated diphenyl ethers (PBDE) concentrations have been reported in cat serum compared with human serum, likely due to cat licking behaviour. This study aimed to extend the present identification of brominated compounds in cat serum, with a focus on hydroxylated metabolites of PBDE, to improve the understanding of feline metabolism of PBDEs. A pooled serum sample from 30 Swedish pet cats with FH was analysed, and brominated species were identified. The results showed exposure to the discontinued flame retardant decabromobiphenyl (BB-209) and technical penta- and octa-BDEs. Altogether 12 PBDE congeners were identified along with 2'-MeO-BDE68. Furthermore, 2,4-dibromophenol, 2,4,6-, 2,4,5- and 2,3,4-tribromophenol plus 2'-OH-BDE68, 6-OH-BDE47, 5-OH-BDE47, 4'-OH-BDE49 were identified. 2,4,6-tribromophenol and 6-OH-BDE47 were the most prominent species in cat serum. Considering that these are natural products, it can be concluded that metabolism of PBDEs to OH-PBDEs is not a major route of PBDE elimination in cats. It is notable that BB-209, 6-OH-BDE47, and 2,4,6-tribromophenol all suggested that endocrine-disrupting chemicals were present in high concentrations in cat serum.

  • 68. Pedersen, Marie
    et al.
    Schoket, Bernadette
    Godschalk, Roger W.
    Wright, John
    von Stedingk, Hans
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Törnqvist, Margareta
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Sunyer, Jordi
    Nielsen, Jeanette K.
    Merlo, Domenico F.
    Mendez, Michelle A.
    Meltzer, Helle M.
    Lukacs, Viktoria
    Landström, Anette
    Kyrtopoulos, Soterios A.
    Kovacs, Katalin
    Knudsen, Lisbeth E.
    Haugen, Margaretha
    Hardie, Laura J.
    Gutzkow, Kristine B.
    Fleming, Sarah
    Fthenou, Eleni
    Farmer, Peter B.
    Espinosa, Aina
    Chatzi, Leda
    Brunborg, Gunnar
    Brady, Nigel J.
    Botsivali, Maria
    Arab, Khelifa
    Anna, Livia
    Alexander, Jan
    Agramunt, Silvia
    Kleinjans, Jos C.
    Segerbäck, Dan
    Kogevinas, Manolis
    Bulky DNA Adducts in Cord Blood, Maternal Fruit-and-Vegetable Consumption, and Birth Weight in a European Mother-Child Study (NewGeneris)2013In: Journal of Environmental Health Perspectives, ISSN 0091-6765, E-ISSN 1552-9924, Vol. 121, no 10, p. 1200-1206Article in journal (Refereed)
    Abstract [en]

    Background: Tobacco-smoke, airborne, and dietary exposures to polycyclic aromatic-hydrocarbons (PAHs) have been associated with reduced prenatal growth. Evidence from -biomarker-based studies of low-exposed populations is limited. Bulky DNA adducts in cord blood reflect the prenatal effective dose to several genotoxic agents including PAHs. Objectives: We estimated the association between bulky DNA adduct levels and birth weight in a multicenter study and examined modification of this association by maternal intake of fruits and vegetables during pregnancy. Methods: Pregnant women from Denmark, England, Greece, Norway, and Spain were recruited in 2006-2010. Adduct levels were measured by the 32P-postlabeling technique in white blood cells from 229 mothers and 612 newborns. Maternal diet was examined through questionnaires. Results: Adduct levels in maternal and cord blood samples were similar and positively correlated (median, 12.1 vs. 11.4 adducts in 108 nucleotides; Spearman rank correlation coefficient = 0.66, p < 0.001). Cord blood adduct levels were negatively associated with birth weight, with an estimated difference in mean birth weight of -129 g (95% CI: -233, -25 g) for infants in the highest versus lowest tertile of adducts. The negative association with birth weight was limited to births in Norway, Denmark, and England, the countries with the lowest adduct levels, and was more pronounced in births to mothers with low intake of fruits and vegetables (-248 g; 95% CI: -405, -92 g) compared with those with high intake (-58 g; 95% CI: -206, 90 g). Conclusions: Maternal exposure to genotoxic agents that induce the formation of bulky DNA adducts may affect intrauterine growth. Maternal fruit and vegetable consumption may be protective.

  • 69. Qiu, Yanling
    et al.
    Strid, Anna
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Bignert, Anders
    Zhu, Zhiliang
    Zhao, Jianfu
    Athanasiadou, Maria
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Athanassiadis, Loannis
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Bergman, Åke
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Chlorinated and brominated organic contaminants in fish from Shanghai markets: A case study of human exposure2012In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 89, no 4, p. 458-466Article in journal (Refereed)
    Abstract [en]

    In the present study were two favorite edible fish species for local residents, i.e., mandarin fish and crawfish, collected from the Shanghai market and analyzed for selected organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), hexabromocyclododecane (HBCDD), polybrominated diphenyl ethers (PBDEs) and methoxylated PBDEs (MeO-PBDEs). Efforts were also made to identify the potential sources of these contaminants. Comparable concentrations of hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethanes (DDTs) and HBCDD were found in muscle tissue of mandarin fish from Guangdong (GDF), the Pearl River Delta and from Taihu Lake (TLF), the Yangtze River Delta. Levels of chlordanes, PCBs and PBDEs were about one magnitude lower in TLF compared to GDF. The concentrations of OCPs in the butter-like gland of the crawfish (CFB) were 2-5 times of those in the crawfish muscle (CFM) while concentrations of PCBs, PBDEs and MeO-PBDEs were comparable. The different patterns and levels of chlorinated and brominated organo-halogen contaminants seen in mandarin fish from GDF and TLF indicates that different types of chemicals might be used in the two delta regions. The present study also shows a good correlation between the concentrations of hexachlorobenzene (HCB) and pentachloroanisol (PCA) in fish for the first time. Fish consumption limits based on chemical contaminants with non-carcinogenic effects were calculated. The estimated maximum daily consumption limit for GDF,TLF, CFM and CFB were 1.5, 2.6, 3.7 and 0.08 kg, respectively, indicating no significant risk regarding the persistent organic pollutants measured in the present study.

  • 70. Rose, Melissa
    et al.
    Bennett, Deborah H.
    Bergman, Åke
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Fängström, Britta
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Pessah, Isaac N.
    Hertz-Picciotto, Irva
    PBDEs in 2-5 Year-Old Children from California and Associations with Diet and Indoor Environment2010In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 44, no 7, p. 2648-2653Article in journal (Refereed)
    Abstract [en]

    This study determined the body burden of PBDEs in 100 California children, and evaluated associations with sociodemographic, household, and dietary factors. In national and international comparisons, California dust, breast milk, and human serum samples contain higher concentrations of PBDEs. Higher levels in children suggest exposure pathways depend upon age. Plasma samples were analyzed for PBDEs using GC/MS. Circulating levels of PBDEs were 10-to 1000-fold higher than similar aged populations in Mexico and Europe, 5-times higher than similar aged children across the U.S., and 2- to 10-fold higher than U.S. adults. Increased levels of higher-brominated congeners were associated with the recent purchase of new upholstered furniture or mattresses and consumption of pork. Concentrations of lower-brominated congeners increased with frequency of poultry consumption. Lower maternal education was independently and significantly associated with higher levels of most congeners in the children.

  • 71.
    Rydén, Andreas
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Marsh, Göran
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Synthesis of polybrominated diphenyl ethers via unsymmetrical diaryliodonium triflatesManuscript (preprint) (Other academic)
    Abstract [en]

    Polybrominated diphenyl ethers (PBDEs) are ubiquitous environmental pollutants due to theirpersistent character and extensive use as additive flame retardants. In order to assess theirbiological effects, fate, environmental concentrations and other parameters related to riskassessment, authentic PBDE congers are needed for research purposes. In the present work anew general method for the preparation of individual PBDE congeners is presented. Themethodology used is based on recent advances in unsymmetrical diaryliodonium saltsynthesis as well as advances in O-arylation of phenols with these types of salts. Accordingly,three brominated diphenyliodonium triflates were prepared i.e. phenyl(2,4,5-tribromophenyl)iodonium triflate, phenyl(2,4,6-tribromophenyl)iodonium triflate andphenyl(2,3,4,6-tetrabromophenyl)iodonium triflate from 1,2,4-tribromo-5-iodobenzene, 1,3,5-tribromo-2-iodobenzene and 1,2,3,5-tetrabromo-4-iodobenzene, respectively. Yields indiaryliodonium salt syntheses ranged from 69-96%. These salts were further used to O-arylatevarious brominated phenols giving individual tetra- to octa-BDE congeners in yields rangingfrom 64-98%. The O-arylation method used was given after a minor optimisation study, regarding reaction time and temperature, which is reported herein. In addition, this O-arylationmethod was also used with two brominated methoxyphenols in the syntheses of twomethoxylated PBDEs.

  • 72.
    Rydén, Andreas
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Strid, Anna
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Athanassiadis, Ioannis
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Bergman, Åke
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Occurrence and potential human exposure to brominated flame retardants at a Swedish smelter handling electronic scrapManuscript (preprint) (Other academic)
    Abstract [en]

    Some well-known brominated flame retardants are common in electronic and electric devices, i.e. polybrominated diphenyl ethers (PBDEs), nowadays particularly the commercial DecaBDE, and tetrabromobisphenol A (TBBPA), but others are used as well. The PBDEs are ubiquitous environmental contaminants while the TBBPA is primarily reported as a contaminant of the abiotic compartments. In this study, personnel at a smelter handling large quantities of shredded printed circuit boards were assessed for potential elevated concentrations of PBDEs, TBBPA and other BFRs. Also dust, sampled at a few sites around the plant, was analysed for BFRs. The dominating BFRs in the dust were decabromodiphenyl ether (BDE-209) and TBBPA, while intermediate levels were indicated for bis(2,4,6-tribromophenoxy)ethane (BTBPE), decabromodiphenyl ethane (DBDPE) and hexabromobenzene (HBB) and only low concentrations of decabromobiphenyl (BB-209) and 2,4,6-tribromophenol (2,4,6-TBP). The workers all showed similar concentrations of the PBDE congeners in serum as recently determined for a Swedish control group. TBBPA was below limit of detection while 2,3,4,6-tetrabromophenol was present in all workers at rather high concentrations. It is yet not known from where this exposure originate, since the compound is not related to BFRs in the dust from the electronic scrap. It is clear that the workers are well protected from the emissions from the printed circuit boards, even though the volumes of electronic scrap handled at the smelter has increased significantly.

  • 73. Smedje, Greta
    et al.
    Lindgren, Torsten
    Jakobsson, Kristina
    Athanassiadis, Ioannis
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Bergman, Åke
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Flame Retardants in Airplanes2011Conference paper (Refereed)
  • 74.
    Strid, Anna
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Athanassiadis, Ioannis
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Athanasiadou, Maria
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Svavarsson, Jörundur
    University of Iceland, Institute of Biology.
    Päpke, Olaf
    Eurofins GfA, Hamburg.
    Bergman, Åke
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Neutral and phenolic brominated organic compounds of natural and anthropogenic origin in Northeast Atlantic Greenland shark (Somniosus microcephalus)2010In: Environmental Toxicology and Chemistry, ISSN 0730-7268, E-ISSN 1552-8618, Vol. 29, no 12, p. 2653-2659Article in journal (Refereed)
    Abstract [en]

    In the present study, muscle and liver tissue from 10 female Greenland sharks (Somniosus microcephalus) collected in Icelandic waters were analyzed for neutral and phenolic brominated organic compounds, including polybrominated diphenyl ethers (PBDEs) and the structurally related methoxylated (MeO) and hydroxylated (OH) PBDEs. Hydroxylated PBDEs exist both as natural products and as metabolites of the anthropogenic PBDEs, whereas MeO-PBDEs appear to exclusively be of natural origin. Other compounds examined were 2′,6-dimethoxy-2,3′,4,5′-tetrabromodiphenyl ether (2′,6-diMeO-BDE68), 2,2′-dimethoxy-3,3′,5,5′-tetrabromobiphenyl (2,2′-diMeO-BB80), 2,4,6-tribromoanisol (2,4,6-TBA) and 2,4,6-tribromophenol, all of natural origin, although 2,4,6-TBA and its phenolic counterpart may also be of anthropogenic origin. The major brominated organic compound was 6-MeO-BDE47, and ΣMeO-PBDE ranged from 49 to 210 ng/g fat in muscle and from 55 to 200 ng/g fat in liver tissue. Total concentrations of PBDEs were lower than ΣMeO-PBDE, in all but one sample, ranging between 7.3 to 190 and 9.9 to 200 ng/g fat in muscle and liver, respectively, and major congeners were BDE-47, BDE-99, and BDE-100. Polybrominated diphenyl ethers were analyzed using both high- and low-resolution mass spectrometry (MS) as a quality assurance, and the results from this comparison were acceptable. In accordance with previous work on Greenland sharks, no size/age-related accumulation was observed. Differences seen in concentrations were instead assumed to be a reflection of different feeding habits among the individuals. Phenolic compounds were only formed/retained in trace amounts in the Greenland shark. Among the phenolic compounds studied were 6-OH-BDE47, 2′-OH-BDE68, and 2,4,6-tribromophenol, all detected in liver and the latter two in muscle

  • 75.
    Sundström, Maria
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Bogdanska, Jasna
    Stockholm University, Faculty of Science, Department of Biochemistry and Biophysics.
    Pham, Hung V.
    Stockholm University, Faculty of Science, Department of Biochemistry and Biophysics.
    Athanasios, Vlastaras
    Stockholm University, Faculty of Science, Department of Biochemistry and Biophysics.
    Nobel, Stefan
    Stockholm University, Faculty of Science, Department of Biochemistry and Biophysics.
    McAlees, Alan
    Eriksson, Johan
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    DePierre, Joseph W.
    Stockholm University, Faculty of Science, Department of Biochemistry and Biophysics.
    Bergman, Åke
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Radiosynthesis of perfluorooctanesulfonate (PFOS) and perfluorobutanesulfonate (PFBS), including solubility, partition and adhesion studies2012In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 87, no 8, p. 865-871Article in journal (Refereed)
    Abstract [en]

    Here, we describe for the first time the synthesis of [S-35] PFOS and [S-35] PFBS with sulfur-35 enriched sulfur dioxide as the radiolabelled reagent, resulting in 2.5 and 2.3 mCi of product, respectively. Basic information concerning the physicochemical properties of perfluorooctanesulfonate (PFOS), perfluorobutanesulfonate (PFBS) and perfluorooctanoic acid (PFOA) are still limited. Hence, we utilized these radiolabelled perfluoroalkanesulfonates (PFSAs), as well as carbon-14 labelled perfluorooctanoic acid a, ([C-14] PFOA) to determine some basic characteristics of physiological and experimental significance. The solubility of PFOS in buffered aqueous solutions at pH 7.4 was found to be severely reduced in the presence of potassium and sodium ions, which, however, did not reduce the solubility of PFOA or PFBS. PFOS was found to adhere to a small extent to polypropylene and polystyrene, whereas no such adhesion of PFOA or PFBS was detected. The extents of adhesion of PFOS and PFOA to glass were found to be 20% and 10%, respectively. For the first time, the partition coefficients for PFOS, PFBS and PFOA between n-octanol and water were determined experimentally, to be -0.7, -0.3, and 1.4, respectively, reflecting the difference in the amphiphilic natures of these molecules.

  • 76.
    Sundström, Maria
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Chang, Shu-Ching
    Noker, Patricia E.
    Gorman, Gregory S.
    Hart, Jill A.
    Ehresman, David J.
    Bergman, Åke
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Butenhoff, John L.
    Comparative pharmacokinetics of perfluorohexanesulfonate (PFHxS) in rats, mice, and monkeys2012In: Reproductive Toxicology, ISSN 0890-6238, E-ISSN 1873-1708, Vol. 33, no 4, p. 441-451Article in journal (Refereed)
    Abstract [en]

    Perfluorohexanesulfonate (PFHxS) has been found in biological samples from wildlife and humans. The human geometric mean serum PFHxS elimination half-life has been estimated to be 2665 days. A series of studies was undertaken to establish pharmacokinetic parameters for PFHxS in rats, mice, and monkeys after single administration with pharmacokinetic parameters determined by WinNonlin (R) software. Rats and mice appeared to be more effective at eliminating PFHxS than monkeys. With the exception of female rats, which had serum PFHxS elimination half-life of approximately 2 days, the serum elimination half-lives in the rodent species and monkeys approximated 1 month and 4 months, respectively, when followed over extended time periods (10-24 weeks). Collectively, these studies provide valuable insight for human health risk assessment regarding the potential for accumulation of PFHxS in humans.

  • 77.
    Sundström, Maria
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Ehresman, David
    3M Company, St. Paul, MN, USA.
    Bignert, Anders
    Enheten för miljögiftsforskning, Naturhistoriska riksmuseet.
    Butenhoff, John L.
    3M Company, St. Paul, MN, USA.
    Olsen, Geary
    3M Company, St. Paul, MN, USA.
    Chang, Shu-Ching
    3M Company, St. Paul, MN, USA.
    Bergman, Åke
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    A temporal trend study (1972-2008) of perfluorooctanesulfonate, perfluorohexanesulfonate, and perfluorooctanoate in pooled human milk samples from Stockholm, Sweden2010In: Environment International, ISSN 0160-4120, E-ISSN 1873-6750, Vol. 37, no 1, p. 178-83Article in journal (Refereed)
    Abstract [en]

    The widespread presence of perfluorooctanesulfonate (PFOS), perfluorooctanoate (PFOA), and perfluorohexanesulfonate (PFHxS) in human general populations and their slow elimination profiles have led to renewed interest in understanding the potential human neonatal exposures of perfluoroalkyls (PFAs) from consumption of human milk. The objective of this study was to evaluate the concentrations of PFOS, PFHxS, and PFOA in pooled human milk samples obtained in Sweden between 1972 and 2008 (a period representing the most significant period of PFA production) and to see whether the time trend of these analytes parallels that indicated in human serum. Chemical analysis of PFOS, PFHxS, and PFOA was performed on pooled Swedish human milk samples from 1972 to 2008 after methodological refinements. The 20 samples which formed the 2007 pool were also analyzed individually to evaluate sample variations. Analyses were performed by HPLC-MS/MS. Due to the complexities of the human milk matrix and the requirement to accurately quantitate low pg/mL concentrations, meticulous attention must be paid to background contamination if accurate results are to be obtained. PFOS was the predominant analyte present in the pools and all three analytes showed statistically significant increasing trends from 1972 to 2000, with concentrations reaching a plateau in the 1990s. PFOA and PFOS showed statistically significant decreasing trends during 2001-2008. At the end of the study, in 2008, the measured concentrations of PFOS, PFHxS, and PFOA in pooled human milk were 75 pg/mL, 14 pg/mL, and 74 pg/mL, respectively. The temporal concentration trends of PFOS, PFHxS, and PFOA observed in human milk are parallel to those reported in the general population serum concentrations.

     

  • 78. Svanfelt, Jesper
    et al.
    Eriksson, Johan
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Kronberg, Leif
    Photochemical transformation of the thyroid hormone levothyroxine in aqueous solution2011In: Environmental Science and Pollution Research, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 18, no 6, p. 871-876Article in journal (Refereed)
    Abstract [en]

    Purpose The direct aqueous photolysis of the thyroid hormone levothyroxine (T(4)) has been studied. Methods and Result One of the major photoproducts, i.e., 4-[4-(2-amino-2-carboxy-ethyl)-2,6-diiodo-phenoxy]-penta-2,4-dienoic acid (P1), was isolated by liquid chromatography and structurally assigned by mass spectrometric (MS) and nuclear magnetic resonance spectroscopic methods. The identity of a second major product, i.e., 3,5-diiodo-l-thyrosine (P3), was confirmed through access to a commercially available standard. Furthermore, the structures of three additional transformation products are proposed on the basis of data obtained by high-resolution MS analyses. UV absorption spectra were determined for T(4) and the two photoproducts P1 and P3. Disappearance quantum yields were calculated for T(4) (I center dot = 0.014 at pH 12) and P3 (I center dot = 0.024 at pH 12 and I center dot = 0.010 at pH 8.5), whereas the compound P1 was found to be stable under the studied conditions (T(1/2) = 600 min). Conclusion The results indicate that solar UV light may have a significant impact on the fate of T(4) in the aquatic environment.

  • 79.
    Unger, Maria
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK). Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Asplund, Lillemor
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Marsh, Göran
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Gustafsson, Örjan
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Characaterization of an abundant and novel methyl- and methoxy-substituted brominated diphenyl ether isolated from whale blubber2010In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 79, no 4, p. 408-413Article in journal (Refereed)
    Abstract [en]

    A previously unidentified yet abundant substituted polybrominated diphenyl ether (PBDE) was isolated from a northern bottlenose whale (Hyperoodon ampullatus) found dead in the Skagerrak, North Sea. A combination of gas chromatography, high and low resolution mass spectrometry and nuclear magnetic resonance spectroscopy (NMR) (1H, 1H–1H and 1H–13C) after isolation with preparative capillary gas chromatography (PCGC) lead to the identification of the unknown substance as 6-MeO-5-Me-2,2′,3,4′-tetrabromo diphenyl ether (6-MeO-5-Me-BDE42). To our knowledge this is only the second time PCGC has been used to isolate individual organohalogen compounds present in trace amounts for identification with NMR. The concentration of this novel bioaccumulated compound was estimated to be about 100 ng g−1 lipid, which was 2.5 times higher compared with the most abundant MeO-PBDE congeners.

  • 80.
    Vikström, A.C.
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Abramsson-Zetterberg, L.
    Athanassiadis, I.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Granath, F.
    Törnqvist, M.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    In vivo doses of acrylamide and glycidamide in humans after intake of acrylalmide-rich food2011In: Toxicological Sciences, ISSN 1096-6080, E-ISSN 1096-0929, Vol. 119, no 1, p. 41-49Article in journal (Refereed)
  • 81.
    Vikström, Anna C.
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Warholm, Margareta
    Paulsson, Birgit
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Axmon, Anna
    Wirfalt, Elisabet
    Törnqvist, Margareta
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Hemoglobin adducts as a measure of variations in exposure to acrylamide in food and comparison to questionnaire data2012In: Food and Chemical Toxicology, ISSN 0278-6915, E-ISSN 1873-6351, Vol. 50, no 7, p. 2531-2539Article in journal (Refereed)
    Abstract [en]

    Measurement of haemoglobin (Hb) adducts from acrylamide (AA) and its metabolite glycidamide (GA) is a possibility to improve the exposure assessment in epidemiological studies of AA intake from food. This study aims to clarify the reliability of Hb-adduct measurement from individual single samples for exposure assessment of dietary AA intake. The intra-individual variations of AA- and GA-adduct levels measured in blood samples collected over 20 months from 13 non-smokers were up to 2-fold and 4-fold, respectively. The corresponding interindividual variations observed between 68 non-smokers, with large differences in AA intake, were 6-fold and 8-fold, respectively. The intra-individual variation of the GA-to-AA-adduct level ratio was up to 3-fold, compared to 11-fold between individuals (n = 68). From AA-adduct levels the average AA daily intake (n = 68) was calculated and compared to that estimated from dietary history methodology: 0.52 and 0.67 mu g/kg body weight and day, respectively. At an individual level the measures showed low association (Rs = 0.39). Conclusions: Dietary AA is the dominating source to measured AA-adduct levels and corresponding inter- and intra-individual variations in non-smokers. Measurements from single individual samples are useful for calculation of average M intake and its variation in a cohort, and for identification of individuals only from extreme intake groups.

  • 82.
    Vikström, Anna C.
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Wilson, Kathryn M.
    Paulsson, Birgit
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Athanassiadis, Ioannis
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Grönberg, Henrik
    Adami, Hans-Olov
    Adolfsson, Jan
    Mucci, Lorelei A.
    Bälter, Katarina
    Törnqvist, Margareta
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Alcohol influence on acrylamide to glycidamide metabolism assessed with hemoglobin-adducts and questionnaire data2010In: Food and Chemical Toxicology, ISSN 0278-6915, E-ISSN 1873-6351, Vol. 58, no 3, p. 820-824Article in journal (Refereed)
    Abstract [en]

    Our purpose was to investigate whether alcohol (ethanol) consumption could have an influence on the metabolism of acrylamide to glycidamide in humans exposed to acrylamide through food. We studied a subsample from a population-based case–control study of prostate cancer in Sweden (CAPS). Questionnaire data for alcohol intake estimates was compared to the ratio of hemoglobin-adduct levels for acrylamide and glycidamide, used as a measure of individual differences in metabolism. Data from 161 non-smoking men were processed with regard to the influence of alcohol on the metabolism of acrylamide to glycidamide. A negative, linear trend of glycidamide-adduct to acrylamide-adduct-level ratios with increasing alcohol intake was observed and the strongest association (p-value for trend = 0.02) was obtained in the group of men with the lowest adduct levels (⩽47 pmol/g globin) when alcohol intake was stratified by acrylamide-adduct levels. The observed trend is likely due to a competitive effect between ethanol and acrylamide as both are substrates for cytochrome P450 2E1. Our results, strongly indicating that ethanol influence metabolism of acrylamide to glycidamide, partly explain earlier observations of only low to moderate associations between questionnaire data on dietary acrylamide intake and hemoglobin-adduct levels.

  • 83.
    von Stedingk, Hans
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Vikström, Anna
    Rydberg, Per
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Pedersen, Marie
    Nielsen, Jeanette K.S.
    Segerbäck, Dan
    Törnqvist, Margareta
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Analysis of hemoglobin adducts from acrylamide, glycidamide and ethylene oxide in paired mother/cordblood samples from Denmark2011In: Chemical Research in Toxicology, ISSN 0893-228X, E-ISSN 1520-5010, Vol. 24, no 11, p. 1957-1965Article in journal (Refereed)
    Abstract [en]

    The knowledge about fetal exposure to acrylamide/glycidamide from the maternal exposure through food is limited. Acrylamide, glycidamide, and ethylene oxide are electrophiles and form adducts with hemoglobin (Hb), which could be used for in vivo dose measurement. In this study, a method for analysis of Hb adducts by liquid chromatography–mass spectrometry, the adduct FIRE procedure, was applied to measurements of adducts from these compounds in maternal blood samples (n = 87) and umbilical cord blood samples (n = 219). The adduct levels from the three compounds, acrylamide, glycidamide, and ethylene oxide, were increased in tobacco smokers. Highly significant correlations were found between cord and maternal blood with regard to measured adduct levels of the three compounds. The mean cord/maternal hemoglobin adduct level ratios were 0.48 (range 0.27–0.86) for acrylamide, 0.38 (range 0.20–0.73) for glycidamide, and 0.43 (range 0.17–1.34) for ethylene oxide. In vitro studies with acrylamide and glycidamide showed a lower (0.38–0.48) rate of adduct formation with Hb in cord blood than with Hb in maternal blood, which is compatible with the structural differences in fetal and adult Hb. Together, these results indicate a similar life span of fetal and maternal erythrocytes. The results showed that the in vivo dose in fetal and maternal blood is about the same and that the placenta gives negligible protection of the fetus to exposure from the investigated compounds. A trend of higher levels of the measured adducts in cord blood with gestational age was observed, which may reflect the gestational age-related change of the cord blood Hb composition toward a higher content of adult Hb. The results suggest that the Hb adduct levels measured in cord blood reflect the exposure to the fetus during the third trimester. The evaluation of the new analytical method showed that it is suitable for monitoring of background exposures of the investigated electrophilic compounds in large population studies.

  • 84. Wahl, M.
    et al.
    Guenther, R.
    Yang, L.
    Bergman, Åke
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Straehle, U.
    Strack, S.
    Weiss, C.
    Polybrominated diphenyl ethers and arylhydrocarbon receptor agonists: Different toxicity and target gene expression2010In: Toxicology Letters, ISSN 0378-4274, E-ISSN 1879-3169, Vol. 198, no 2, p. 119-126Article in journal (Refereed)
    Abstract [en]

    Polybrominated diphenyl ethers (PBDEs) accumulate in the environment and in humans. PBDEs are developmental neurotoxicants, disturb the endocrine system and induce tumors in rodents. However, underlying mechanisms of PBDE toxicity are still insufficiently understood. Some reports demonstrated activation but also inhibition of the aryl hydrocarbon receptor (AhR) by PBDEs based on expression of its target gene cyp1A1. In the present study, we used different PBDE congeners (BDE47, 99, 153 and 209) and analyzed their effects on AhR signaling in various cell lines and zebrafish embryos. Furthermore, we performed microarray experiments in rat hepatoma cells to compare changes in gene expression induced by either BDE47 or the AhR agonist 2,3,7,8-tetrabromo-dibenzofuran (TBDF). PBDEs did not activate but rather inhibited AhR signaling and specifically induced malformations in zebrafish embryos, which differ from those provoked by AhR agonists. Furthermore, BDE47 and TBDF differentially regulated global gene expression in hepatoma cells. Hence. PBDEs and AhR agonists trigger different toxicity and target gene expression. Several novel target genes of BDE47 and TBDF were identified and verified by RT-PCR. TBDF induced expression of the transcriptional regulators Sim2 and RevErb beta whereas BDE47 specifically deregulated expression of two subunits of the cytochrome c oxidase complex, cox6a2 and cox4i2, which might be linked to its toxicity.

  • 85.
    Westberg, Emelie A. C.
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Singh, Rajinder
    Hedebrant, Ulla
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Koukouves, Georgios
    Souliotis, Vassilis L.
    Farmer, Peter B.
    Segerbäck, Dan
    Kyrtopoulos, Soterios
    Törnqvist, Margareta Å.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Adduct levels from benzo[a]pyrenediol epoxide: Relative formation to histidine in serum albumin and to deoxyguanosine in DNA in vitro and in vivo in mice by LC/MS-MS methods2015In: Toxicology Letters, ISSN 0378-4274, E-ISSN 1879-3169, Vol. 232, no 1, p. 28-36Article in journal (Refereed)
    Abstract [en]

    Stable and specific biomacromolecular adducts can be used to measure in vivo doses of reactive compounds. An LC/MS-MS method to measure adducts from the benzo[a]pyrene (BP) metabolite (±)-anti-BP-7,8-diol-9,10-epoxide ((±)-anti-BPDE) to His146 in serum albumin (SA), earlier evaluated on in vitro alkylated human SA, was tested for its applicability to mouse. It was shown that (+)-anti-BPDE form BPDE-His adducts to mouse SA. The method was applied to samples from BP-exposed mice (100 mg/kg of body weight for 1, 3, 7 and 28 days). BPDE-His in SA was close to the limit of quantification and showed the highest level (13 fmol/mg) 3 days after exposure. The level was 400 times lower (calculated per g macromolecule) than earlier measured level of BPDE-adduct to deoxyguanosine (dG) in DNA in the livers. The relative rate of formation of adducts from BPDE with His in SA and with dG in DNA was investigated. Quantification by LC/MS-MS of the adducts in human blood alkylated in vitro with (±)-anti-BPDE showed a 1850 times higher level of BPDE-dG compared to BPDE-His. The specific and stable BPDE-adducts to His in SA are potential biomarkers of in vivo dose of BPDE, though this requires a considerable improved analytical sensitivity of the LC/MS-MS method.

  • 86.
    Westberg, Emelie
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Motwani, Hitesh
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Lindh, Christian
    Abramsson-Zetterberg, Lilianne
    Törnqvist, Margareta
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Comparison of specific biomarkers of internal dose and genotoxic effect after exposure to BP with the aim to use in risk assessmentManuscript (preprint) (Other academic)
  • 87. Westerink, R.H.S.
    et al.
    Heusinkveld, H.J.
    Bergman, Åke
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    van den Berg, M
    Dingemans, M.M.L.
    Inhibition of the depolarization-evoked increase in intracellular calcium levels and catecholamine exocytosis by hexabromocyclododecane (HBCD) in PC12 cells2010In: Organohalogen Compounds, 2010Conference paper (Other academic)
  • 88. Westerink, R.H.S.
    et al.
    van den Berg, M
    Bergman, Åke
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Dingemans, M.M.L.
    Hydroxylation increases the neurotoxic potential of the brominated flame retardant BDE-47: The structure of BDE-47 Metabolites determines the potency to affect calcium homeostasis in PC12 cells2010In: Organohalogen Compounds, 2010Conference paper (Other academic)
  • 89.
    Winnberg, Ulrika
    et al.
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Rydén, Andreas
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Löfstrand, Karin
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Asplund, Lillemor
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Bignert, Anders
    Marsh, Göran
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Novel Octabrominated Phenolic Diphenyl Ether Identified in Blue Mussels from the Swedish West Coast2014In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 48, no 6, p. 3319-3326Article in journal (Refereed)
    Abstract [en]

    Hydroxylated (OH−) and methoxylated (MeO−) polybrominated diphenyl ethers (PBDEs) are compounds present in the marine environment and OH–PBDEs are of toxicological concern and are therefore of interest to monitor in the environment. A phenolic octaBDE was tentatively identified in the phenolic fraction of previously analyzed mussel samples after methylation of the halogenated phenolic compounds (HPCs). The aim of the present study was to confirm the identity of this compound in blue mussels and investigate whether the analyte is diOH– and/or OH–MeO–octaBDE. Two reference standards, 6,6′-dimethoxy-2,2′,3,3′,4,4′,5,5′-octabromodiphenyl ether (6,6′-diMeO–BDE194) and 6-ethoxy-6′-methoxy-2,2′,3,3′,4,4′,5,5′-octabromodiphenyl ether (6-EtO-6′-MeO–BDE194) were prepared via O-arylation of 2,3,4,5-tetrabromo-6-methoxyphenol and 2,3,4,5-tetrabromo-6-ethoxyphenol, respectively, with a novel unsymmetrical diaryliodonium salt, 2,3,4,5-tetrabromo-6-methoxydiphenyliodonium triflate. The GC retention time and GC/MS spectrum of the synthesized 6,6′-diMeO–BDE194 correspond well with the analyte in the methylated phenolic fraction of a mussel extract from a previous study. Structural analysis performed in this study indicate that the synthesized 6,6′-diMeO–BDE194 and 6-EtO-6′-MeO–BDE194 correspond well with 6-hydroxy-6′-methoxy-2,2′,3,3′,4,4′,5,5′-octabromodiphenyl ether (6-OH–6′-MeO–BDE194) after methylation and ethylation, respectively, of the HPCs in the mussel extracts. The compound 6-OH–6′-MeO–BDE194 was identified and quantified in new mussels, sampled in 2012 from two locations on the Swedish west coast, with geometric mean concentrations of 3700 and 410 ng/g fat, respectively.

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