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  • 151.
    Jönsson, Sofie
    et al.
    Örebro University, Department of Natural Sciences.
    Hagberg, Jessika
    Örebro University, Department of Natural Sciences.
    Lahoutifard, N.
    van Bavel, Bert
    Örebro University, Department of Natural Sciences.
    Microextraction by packed sorbent: a new technique for the analysis of small brominated and chlorinated aromatic compounds2008In: Organohalogen Compounds, 2008, Vol. 70, p. 2200-2203Conference paper (Refereed)
  • 152.
    Jönsson, Sofie
    et al.
    Örebro University, Department of Natural Sciences.
    Hagberg, Jessika
    Örebro University, Department of Natural Sciences.
    van Bavel, Bert
    Örebro University, Department of Natural Sciences.
    Determination of 2,4,6-trichloroanisole and 2,4,6-tribromoanisole in wine using microextraction in packed syringe and gas chromatography mass spectrometryManuscript (preprint) (Other academic)
  • 153.
    Jönsson, Sofie
    et al.
    Örebro University, Department of Natural Sciences.
    Hagberg, Jessika
    Örebro University, Department of Natural Sciences.
    van Bavel, Bert
    Örebro University, Department of Natural Sciences.
    Determination of 2,4,6-trichloroanisole and 2,4,6-tribromoanisole in wine using microextraction in packed syringe and gas chromatography-mass spectrometry2008In: Journal of Agricultural and Food Chemistry, ISSN 0021-8561, E-ISSN 1520-5118, Vol. 56, no 13, p. 4962-4967Article in journal (Refereed)
    Abstract [en]

    A selective and fast method for the quantitative determination of 2,4,6-trichloroanisole (TCA) and 2,4,6-tribromoanisole (TBA) in wine was developed. Microextraction in packed syringe (MEPS) was optimized for the extraction and preconcentration of the analytes using extremely small volume samples (0.1-1 mL). For GC-EI-MS, the limit of detection (LOD) for red and white wine was in the range 0.17-0.49 mu g L-1 for TCA and TBA. In addition to GC-EI-MS both GC-NCI-MS and GC-HRMS were used to further improve both selectivity and sensitivity. The lowest LODs were achieved using GC-HRMS in the El mode. In red and white wine samples the LODs were between 0.22-0.75 ng L-1 for TCA and TBA. The reproducibility and linearity for the GC-HRMS method was good, with RSD-values of 4-10% for spiked red wine samples at 1 ng L-1 and linearity with R-2 > 0.962 over a concentration range of 1 to 100 ng L-1.

  • 154.
    Jönsson, Sofie
    et al.
    Örebro University, Department of Natural Sciences.
    Uusitalo, Terhi
    van Bavel, Bert
    Örebro University, Department of Natural Sciences.
    Gustafsson, Inga-Britt
    Örebro University, Department of Restaurant & Culinary Arts.
    Lindström, Gunilla
    Örebro University, Department of Natural Sciences.
    Determination of 2,4,6-trichloroanisole and 2,4,6-tribromoanisole on ng L-1 to pg L-1 levels in wine by soild-phase microextraction and gas chromatography-high-resolution mass spectrometry2006In: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1111, no 1, p. 71-75Article in journal (Refereed)
    Abstract [en]

    A gas chromatography-high-resolution mass spectrometry (GC-HRMS) method using solid-phase microextraction (SPME) for the determination of 2,4,6-trichloroanisole (TCA) and 2,4,6-tribromoanisole (TBA) in wine at low ng L−1 levels was developed. A robust SPME method was developed by optimizing several different parameters, including type of fiber, salt addition, sample volume, extraction and desorption time. The quantification limit for TCA and TBA in wine was lowered substantially using GC-HRMS in combination with the optimized SPME method and allowed the detection of low analyte concentrations (ng L−1) with good accuracy. Limits of quantification for red wine of 0.3 ng L−1 for TCA and 0.2 ng L−1 for TBA with gas chromatography-negative chemical ionization mass spectrometry and 0.03 ng L−1 for TCA and TBA were achieved using GC-HRMS. The method was applied to 30 wines of which 4 wines were sensorically qualified as cork defected. TCA was found in three of these wines with concentrations in the range 2–25 ng L−1. TBA was not detected in any of the samples.

  • 155.
    Kalbin, Georgi
    et al.
    Örebro University, Department of Natural Sciences.
    Hidema, Jun
    Brosché, Mikael
    Kumagai, Tadashi
    Bornman, Janet F.
    Strid, Åke
    Örebro University, Department of Natural Sciences.
    UV-B-induced DNA damage and expression of defence genes under UV-B stress: tissue-specific molecular marker analysis in leaves2001In: Plant, Cell and Environment, ISSN 0140-7791, E-ISSN 1365-3040, Vol. 24, no 9, p. 983-990Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to investigate the regulatory effect of ultraviolet-B (UV-B) radiation on a number of key stress response genes found in the epidermis and mesophyll of Pisum sativum L., Argenteum mutant. This mutant was chosen for the ease with which the entire epidermis can be removed from the mesophyll tissue. An additional goal was to explore the potential modifying effect of pre-acclimation of plants to UV-B radiation prior to exposure by UV-B during treatment. Results showed that mRNA accumulation was similar during acute short-term UV-B exposure for chalcone synthase (Chs) and short-chain alcohol dehydrogenase (SadA) in both epidermis and mesophyll. In contrast, the mRNA levels differed considerably between tissues for phenylalanine ammonia lyase, chalcone isomerase and lipid transfer protein. After 24 h incubation in visible light after cessation of UV-B exposure, the regulation of mRNA levels also differed between Chs and SadA, the former showing no expression in the epidermis and the latter none in the mesophyll. Acclimation to low UV-B levels before acute exposures resulted in delayed induction of Chs and SadA. Measurements of UV-B-induced cyclobutane pyrimidine dimers (CPDs) showed a greater formation in epidermis than in mesophyll. In addition, acclimation at low UV-B levels resulted in significantly higher basal levels of CPDs than in non-acclimated plants in both mesophyll and epidermis and also in increased damage in concomitant acute exposures. The lack of correlation between the number of CPDs and levels of transcripts for defence genes, indicates that DNA damage does not control transcription of these genes.

  • 156.
    Kalbin, Georgi
    et al.
    Örebro University, Department of Natural Sciences.
    Li, Shaoshan
    Örebro University, Department of Natural Sciences.
    Olsman, Helena
    Örebro University, Department of Natural Sciences.
    Pettersson, Mikael
    Engwall, Magnus
    Örebro University, Department of Natural Sciences.
    Strid, Åke
    Örebro University, Department of Natural Sciences.
    Effects of UV-B in biological and chemical systems: equipment for wavelength dependence determination2005In: Journal of Biochemical and Biophysical Methods, ISSN 0165-022X, E-ISSN 1872-857X, Vol. 65, no 1, p. 1-12Article in journal (Refereed)
    Abstract [en]

    The thinning of the stratospheric ozone layer has prompted a large number of studies of UV-B-induced effects in biological and chemical systems. The wavelength dependency of such effects is of interest from mechanistic, physiological or economic points of view. Here, we describe an apparatus for determining the wavelength dependency of UV-B effects in biological and chemical systems. The apparatus consists of a high intensity UV radiation source and narrow bandpass filters to produce UV radiation in even intervals (between 280 and 360 nm). The usefulness of the equipment is demonstrated in two different systems: 1) Chalcone synthase (CHS) gene is up-regulated by UV-B radiation. Therefore quantitative analysis of the CHS gene expression was chosen in the present investigation for studies of the wavelength dependency of gene expression regulation in plants. Maximum induction of CHS expression was found at 300 nm with a 12-fold induction compared with the control; 2) The wavelength dependency of formation of dioxin-like photoproducts from the brominated flame retardant decabrominated diphenyl ether (DeBDE) is described. This is an example of UV-B-induced conversion of non-toxic species into a number of products of which some may be toxic in the environment. In the UV interval studied, the highest dioxin-like activity was found in the sample irradiated at 330 nm and therefore this wavelength is most important for the mechanism involved in photoconversion of DeBDE.

  • 157.
    Kalbina, Irina
    Örebro University, Department of Natural Sciences.
    The molecular mechanisms behind perception and signal transduction of UV-B irradiation in Arabidopsis thaliana2005Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Elevation of UV-B radiation (280-315 nm), occurring as a result of depletion of the stratospheric ozone, causes a number of physiological and biochemical changes in plants. Damage to the photosynthetic apparatus (including the bleaching of the pigments which trap the sun's energy), to the processes of cell division and growth regulation, and to the composition and replication of genetic material are just some of these changes. The consequences include reduction in growth yield, changes in levels and effects of plant hormones and secondary metabolites, and alteration of interactions between plants and other organisms.

    This thesis deals with several mechanistic questions related to regulation of responses during UV-B stress in plants. Our results show significant ecotype-specific variability in UV-B response in the model plant Arabidopsis thaliana. Differences at the molecular level (expression of PR-5 and steady-state concentration of H2O2) resulted in statistically significant differences in biomass, rosette size and leaf area. Therefore, it is of great importance to pay attention to the responses of the background ecotypes when for instance studying mechanisms of responses toward ultraviolet-B radiation in mutants.

    Using a DNA microarray approach, we found a number of novel genes to be differentially expressed under UV-B radiation. Two of the genes (PYROA and MEB5.2) were later used as molecular markers for monitoring of UV-B stress. Promoters of PYROA and MEB5.2 were compared with promoters of genes for the phenylpropanoid pathway. The comparisons indicated only few common elements with the UV-B-regulated promoters of CHS, PAL and CHI. In contrast, the genes identified as being UV-B regulated in this study (MEB5.2, PYROA and UBQ3), completely lacked elements required for the UV-B induction of CHS, indicating that these genes are regulated by different transcription factors. In addition, novel unidentified cis-elements are probably also present upstream of the transcription start.

    Reverse and forward genetics were used for searching novel genes responsive to UV-B and for examination of proposed candidates of the UV-B signal transduction chain. Screening of more than 2000 T-DNA mutants for differential response to UV-B resulted in the identification of a mutant displaying insensitivity to UV-B induced inhibition of hypocotyl growth. By using the corresponding knock-out mutants, the involvement of NADPH oxidase and MAPK phosphatase 1 in UV-B signalling was demonstrated.

    For the plant to be able to respond appropriately to UV-B irradiation, UV-B quanta have to be absorbed. There are indirect evidences for the existence of specific UV-B receptor(s), whereas the receptor itself still remains unknown. By the classical approach of action spectroscopy, we undertook an attempt to identify the absorption spectra of the chromophore(s) sensing UV-B radiation in plants. The investigated molecular markers revealed the presence of two potential chromophores absorbing in the UV-B region and peaking at 280-290 and 300 nm, respectively.

    List of papers
    1. Gene regulation by low level UV-B radiation: identification by DNA array analysis
    Open this publication in new window or tab >>Gene regulation by low level UV-B radiation: identification by DNA array analysis
    Show others...
    2002 (English)In: Photochemical and Photobiological Sciences, ISSN 1474-905X, E-ISSN 1474-9092, Vol. 1, no 9, p. 656-664Article in journal (Refereed) Published
    Abstract [en]

    UV-B radiation alters transcript levels of various defence genes and photosynthetic genes in plants. Utilising a DNA array with 5000 ESTs and cDNAs from Arabidopsis thaliana, 70 genes were found to show a greater than two-fold induction or repression of transcript levels. Six genes (MEB5.2, PyroA, Ubq3, Lhcb6, F5D21.10 and the gene for an RNA polymerase II subunit) were tested for stress specific gene regulation on northern blots with RNA from plants exposed to low dose UV-B radiation, ozone or wounding. Transcript levels for PyroA, Uhq3 and the gene for a RNA polymerase II subunit were all specifically increased by UV-B. MEB5.2 mRNA levels also rose, whereas Lhcb6 and FSD21.10 transcript levels decreased under all stresses. The PyroA gene product in fungi is needed for biosynthesis of pyridoxine, and might have a role in protection against singlet oxygen. The Ubq3 gene encodes the ubiquitin protein that is attached to proteins destined for degradation. MEB5.2 and F5D21.10 represent novel gene products whose function have not yet been identified. Pairwise comparisons between the UV-B inducible promoters have identified a series of elements present in the MEB5.2 and PyroA promoters, absent from promoters of genes for early phenylpropanoid metabolism and that may be responsible for modulating their UV-B responses.

    Keywords
    Arabidopsis/genetics/radiation effects, Base Sequence, DNA; Plant/genetics, Expressed Sequence Tags, Gene Expression Regulation; Enzymologic/radiation effects, Gene Expression Regulation; Plant/*radiation effects, Molecular Sequence Data, Oligonucleotide Array Sequence Analysis, Plant Proteins/genetics, Promoter Regions (Genetics), RNA Polymerase II/genetics, Ultraviolet Rays
    National Category
    Biochemistry and Molecular Biology
    Research subject
    Biochemistry
    Identifiers
    urn:nbn:se:oru:diva-2879 (URN)10.1039/B202659G (DOI)12665302 (PubMedID)
    Available from: 2005-09-14 Created: 2005-09-14 Last updated: 2017-12-14Bibliographically approved
    2. Supplementary ultraviolet-B irradiation reveals differences in stress responses between Arabidopsis thaliana ecotypes
    Open this publication in new window or tab >>Supplementary ultraviolet-B irradiation reveals differences in stress responses between Arabidopsis thaliana ecotypes
    2005 (English)Manuscript (preprint) (Other academic)
    National Category
    Biochemistry and Molecular Biology
    Research subject
    Biochemistry
    Identifiers
    urn:nbn:se:oru:diva-2880 (URN)
    Available from: 2005-09-14 Created: 2005-09-14 Last updated: 2017-10-18Bibliographically approved
    3. Wavelength dependence of expression of UV-B-induced molecular markers in Arabidopsis thaliana
    Open this publication in new window or tab >>Wavelength dependence of expression of UV-B-induced molecular markers in Arabidopsis thaliana
    (English)Manuscript (Other academic)
    National Category
    Biochemistry and Molecular Biology
    Research subject
    Biochemistry
    Identifiers
    urn:nbn:se:oru:diva-2881 (URN)
    Available from: 2005-09-14 Created: 2005-09-14 Last updated: 2017-10-18Bibliographically approved
    4. The role of NADPH oxidase and MAP kinase phosphatase 1 in UV-B-dependent gene expression in Arabidopsis
    Open this publication in new window or tab >>The role of NADPH oxidase and MAP kinase phosphatase 1 in UV-B-dependent gene expression in Arabidopsis
    (English)Manuscript (Other academic)
    National Category
    Biochemistry and Molecular Biology
    Research subject
    Biochemistry
    Identifiers
    urn:nbn:se:oru:diva-2882 (URN)
    Available from: 2005-09-14 Created: 2005-09-14 Last updated: 2017-10-18Bibliographically approved
    5. An Arabidopsis mutant responsive to UV-B irradiation
    Open this publication in new window or tab >>An Arabidopsis mutant responsive to UV-B irradiation
    (English)Manuscript (Other academic)
    National Category
    Biochemistry and Molecular Biology
    Research subject
    Biochemistry
    Identifiers
    urn:nbn:se:oru:diva-2883 (URN)
    Available from: 2005-09-14 Created: 2005-09-14 Last updated: 2017-10-18Bibliographically approved
  • 158.
    Kalbina, Irina
    et al.
    Örebro University, Department of Natural Sciences.
    Li, Shaoshan
    Björn, Lars Olof
    Strid, Åke
    Örebro University, Department of Natural Sciences.
    Wavelength dependence of expression of UV-B-induced molecular markers in Arabidopsis thalianaManuscript (Other academic)
  • 159.
    Kalbina, Irina
    et al.
    Örebro University, Department of Natural Sciences.
    Li, Shaoshan
    Örebro University, Department of Natural Sciences.
    Kalbin, Georgi
    Örebro University, Department of Natural Sciences.
    Björn, Lars Olof
    Strid, Åke
    Örebro University, Department of Natural Sciences.
    Two separate UV-B radiation wavelength regions control expression of different molecular markers in Arabidopsis thaliana2008In: Functional Plant Biology, ISSN 1445-4408, E-ISSN 1445-4416, Vol. 35, no 3, p. 222-227Article in journal (Refereed)
    Abstract [en]

    Fluence-response curves were obtained at nine wavelengths in the interval 280-360 nm for mRNA transcripts of four molecular markers induced by ultraviolet-B (UV-B) radiation in Arabidopsis thaliana: CHS (encoding chalcone synthase), PDX1.3 (encoding an enzyme involved in formation of pyridoxine), MEB5.2 (encoding a protein with unknown function but which is strongly up-regulated by UV-B), and LHCB1*3 (encoding a chlorophyll a/b binding protein). Intact Arabidopsis plants were irradiated for 3h using a high intensity deuterium radiation source and narrow bandwith filters (Kalbin et al. 2005, J. Biochem. Biophys. Meth. 65, 1-12) without supplementary PAR. The results obtained suggest the existence of two distinct UV-B signal responses: one sensitive between 300 and 310 nm and the other sensitive around 280-290 nm. Among the investigated molecular markers, CHS and PDX1.3 were regulated through the chromophore absorbing around 300 nm, whereas MEB5.2 and LHCB1*3 were regulated through the chromophore absorbing at 280-290 nm. The results obtained show that at least two signal transduction pathways exist that regulate gene expression as a result of absorption of UV-B radiation in plants.

  • 160.
    Kalbina, Irina
    et al.
    Örebro University, Department of Natural Sciences.
    Strid, Åke
    Örebro University, Department of Natural Sciences.
    An Arabidopsis mutant responsive to UV-B irradiationManuscript (Other academic)
  • 161.
    Kalbina, Irina
    et al.
    Örebro University, Department of Natural Sciences.
    Strid, Åke
    Örebro University, Department of Natural Sciences.
    Supplementary ultraviolet-B irradiation reveals differences in stress responses between Arabidopsis thaliana ecotypes2005Manuscript (preprint) (Other academic)
  • 162.
    Kalbina, Irina
    et al.
    Örebro University, Department of Natural Sciences.
    Strid, Åke
    Örebro University, Department of Natural Sciences.
    Supplementary ultraviolet-B irradiation reveals differences in stress responses between Arabidopsis thaliana ecotypes2006In: Plant, Cell and Environment, ISSN 0140-7791, E-ISSN 1365-3040, Vol. 29, no 5, p. 754-763Article in journal (Refereed)
    Abstract [en]

    Irradiation of Arabidopsis thaliana ecotypes C24, Wassilewskija (Ws) and Columbia-0 (Col-0) with supplementary ultraviolet-A+B (UV-A+B) radiation revealed ecotype-specific differences in expression of the gene for the pathogenesis-related protein PR-5. C24 showed an increased expression level of PR-5 (5- and 20-fold higher compared with Col-0 and Ws, respectively). Expression of other molecular markers such as CHS (encoding chalcone synthase), MEB5.2 [encoding a gene strongly up-regulated by ultraviolet-B (UV-B)] and PYROA [encoding a pyridoxine (Vitamin B6) biosynthesis enzyme] only showed slight differences between ecotypes. Oxidative stress during UVA+B exposure was monitored by staining for H2O2. This analysis also revealed important ecotype-specific differences. 'H2O2 hot spots' were found in C24, whereas an even distribution of H2O2 was found in Ws and Col-0. Necrotic lesions also appeared on C24 leaves after prolonged UV-B exposure. There was a reverse correlation between the H2O2 steady-state concentration and the PR-5 gene expression; Ws showed the highest level of H2O2 accumulation but the lowest expression level of the PR-5 gene. Furthermore, application of paraquat on the rosettes led to similar PR-5 expression and H2O2 accumulation patterns as were found after UV-A+B irradiation. The observed ecotypic differences were also reflected in a statistically significant UV-B-dependent decrease in biomass, rosette size and leaf area for Ws, but not for C24 and Col-0. Our results show that a significant ecotype-specific genetic variability in general UV-B responses in Arabidopsis exists. Moreover, the signal transduction or gene regulation pathway for PR-5 differs from the other molecular markers used in this study.

  • 163.
    Kalbina, Irina
    et al.
    Örebro University, Department of Natural Sciences.
    Strid, Åke
    Örebro University, Department of Natural Sciences.
    The role of NADPH oxidase and MAP kinase phosphatase 1 in UV-B-dependent gene expression in ArabidopsisManuscript (Other academic)
  • 164.
    Kalbina, Irina
    et al.
    Örebro University, Department of Natural Sciences.
    Strid, Åke
    Örebro University, Department of Natural Sciences.
    The role of NADPH oxidase and MAP kinase phosphatase in UV-B-dependent gene expression in Arabidopsis2006In: Plant, Cell and Environment, ISSN 0140-7791, E-ISSN 1365-3040, Vol. 29, no 9, p. 1783-1793Article in journal (Refereed)
    Abstract [en]

    Plant responses to supplementary UV-B irradiation have been reported to include formation of reactive oxygen species (ROS), hydrogen peroxide, in particular, and regulation by mitogen-activated protein kinase (MAPK) cascades which in turn are fine-tuned by MAPK phosphatases (MKPs). Here we present direct genetic evidence for the involvement of plasma membrane NADPH oxidase, a source of superoxide and hydrogen peroxide in the apoplasts, in UV-B signalling in Arabidopsis thaliana, by analysis of gene expression of the UV-B molecular markers in NADPH oxidase (atrbohD, F and DF) and MAP kinase phosphatase 1 (MKP1) knockout mutants (mkp1). Whereas the NADPH oxidase mutants were affected in UV-B-dependent CHS, PYROA and MEB5.2 gene expression, the mkp1 mutant was affected in the general expression pattern of the pathogenesis-related (PR) and PDF1.2 genes. The results indicate involvement of MKP1 in repressive action on gene expression of more general stress response pathways, similar to those activated by pathogen attack, while NADPH oxidase is involved in quantitative (rather than absolute) regulation of more UV-B-specific genes. The expressions of the molecular markers in the knockout mutant mkp1 and in its complemented lines (lines 6 and 10) were similar, as opposed to the responses of the corresponding wild-type Wassilewskija-4 (Ws-4). Lines 6 and 10 showed much higher MKP1 mRNA than Ws-4 but did not complement the mutant. This suggests a complex dependency of the MAPK phosporylation level of the PR and PDF1.2 genes. Both NADPH oxidase mutants and the mkp1 mutant phenotypically responded to UV-B by growth retardation.

  • 165.
    Karlsson, Johnny
    et al.
    Örebro University, Department of Natural Sciences.
    von Hofsten, Jonas
    Olsson, Per-Erik
    Institutionen för Molekylärbiologi, Umeå Universitet.
    Generating transparent zebrafish: a refined method to improve detection of gene expression during embryonic development2001In: Marine Biotechnology, ISSN 1436-2228, E-ISSN 1436-2236, Vol. 3, no 6, p. 522-527Article in journal (Refereed)
    Abstract [en]

    In zebrafish (Danio rerio) pigmentation is initiated during embryogenesis and begins in the retinal epithelium and in the melanophores. The pigment cells develop rapidly, and within hours they constitute a prominent feature of the embryo. In order to improve signal detection by whole mount in situ hybridization, confocal microscopy, or expression of GFP, embryos may be treated with 1-phenyl 2-thiourea (PTU) during embryogenesis. PTU inhibits melanogenesis by blocking all tyrosinase-dependent steps in the melanin pathway but can be toxic at high concentrations. The embryos remain transparent as long as the PTU treatment is continued. However, PTU treatment must be initiated before the initial pigmentation because it does not remove already formed pigment. Here we provide a protocol for generating transparent zebrafish while avoiding the toxic and teratogenic effects of PTU treatment.

  • 166.
    Karlsson, Marie
    Örebro University, Department of Natural Sciences.
    Levels of brominated flame retardants in humans and their environment: occupational and home exposure2006Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Plasma from workers at an electronic dismantling plant were analysed for tri- to heptaBDEs (brominated diphenyl ethers), during 18 months. The different exposed groups showed concentrations ranging from 0.06to 2.8 ng g-1 (l.w.). Only BDE #153 and #183 showed elevated levels compared to the general population in Sweden. The levels in the workers were approximately one order of magnitude higher. No clear trend of increased BDE levels was seen during the study period, nor was there a reduction of the plasma concentration during and after the vacation.

    Air levels of tri- to decaBDEs, BTBPE (1,2-bis(2,4,6-tribromophenoxy)-ethane) and DeBDethane (1,2-bis(pentabromophenyl)ethane) ranging from 0.082 to 370 ng m-3 were determined at the same electronic dismantling facility. A comparison was made to the levels reported in this facility before an increase of the production volume. The levels of tri- to hexaBDEs, the main compounds in the commercial PentaBDE mixture, were very similar 2001-02 and 2005. Hepta- to decaBDEs, which are the main components in the Octa- and DecaBDE mixtures, were about three to five times higher in 2005 than in 2001-02. The mean level for BTBPE was two times higher 2001-02 while the concentration of DeBDethane measured 73 times higher 2005.

    Levels of tri- to decaBDEs, BTBPE and DeBDethane were also determined in air, dust and human plasma from households. The levels of the individual BDEs in the plasma samples varied between <0.41 ng g-1 (l.w.) to 17 ng g-1 (l.w). BDE #28 and #47 were present in all air samples, with mean values of 0.015 and 0.12 ng m-3, respectively. BDE #209 was only found in one air sample at a concentration above the detection limit. DeBDethane was detected in only one sample, at a level of 0.023 ng m-3. All the analytes were found in the dust samples at levels ranging from 0.51 to 1600 ng g-1, the highest concentrations were found for BDE #209. DeBDethane was among the most abundant BFRs in the dust at a mean concentration of 47 ng g-1. The concentrations of the sumBDE showed a positive relationship in dust and plasma.

    Eggs from Northern fulmars (Fulmarus glacialis) in the Faroe Islands were sampled for BFRs to establish the levels in remote regions. . The content of tri- to heptaBDEs, BDE #209 and BTBPE were determined in nine samples in concentrations ranging from non-detectable (< 0.02 ng g−1 l.w.) to 7 ng g−1(l.w.). BTBPE was detected in eight samples at a mean level of 0.11 ng g−1 (l.w).

    All work included substantial method development and adaption of existing methods. Validation of a solid phase extraction (SPE) method to analyse tri- to heptabrominated diphenyl ethers in human plasma was performed. The SPE extraction method was found to be faster and less solvent- and sample-demanding, compared to the previously used open column extraction based method.

    List of papers
    1. Solid-phase extraction of polybrominated diphenyl ethers in human plasma: comparison with an open column extraction method
    Open this publication in new window or tab >>Solid-phase extraction of polybrominated diphenyl ethers in human plasma: comparison with an open column extraction method
    2005 (English)In: Chromatographia, ISSN 0009-5893, E-ISSN 1612-1112, Vol. 61, no 1-2, p. 67-73Article in journal (Refereed) Published
    Abstract [en]

    A solid phase extraction (SPE) method in combination with silica gel cleanup to analyse tri-to heptabrominated diphenyl ethers in human plasma was validated. All congeners showed recoveries over 70% except for BDE #183, which showed recoveries around 45%. The method was tested on 21 individual plasma samples which were extracted with both the SPE method and an open column extraction method using Hydromatrix. Method detection limits were of the same order of magnitude for both methods, ranging from 0.0076 to 0.13 ng g−1 (l.w.) depending on the congener. The SPE extraction method meets the demand for a faster, less solvent-and sample-demanding method with lower contamination risk due to fewer steps compared to the open column extraction.

    National Category
    Chemical Sciences Natural Sciences
    Research subject
    Chemistry; Enviromental Science
    Identifiers
    urn:nbn:se:oru:diva-3143 (URN)10.1365/s10337-004-0461-z (DOI)
    Available from: 2006-10-13 Created: 2006-10-13 Last updated: 2017-12-14Bibliographically approved
    2. Polybrominated diphenyl ethers: plasma levels and thyroid status of workers at an electronic recycling facility
    Open this publication in new window or tab >>Polybrominated diphenyl ethers: plasma levels and thyroid status of workers at an electronic recycling facility
    Show others...
    2005 (English)In: International Archives of Occupational and Environmental Health, ISSN 0340-0131, E-ISSN 1432-1246, Vol. 78, no 7, p. 584-592Article in journal (Refereed) Published
    Abstract [en]

    Objectives: Personnel working with electronic dismantling are exposed to polybrominated diphenyl ethers (PBDEs), which in animal studies have been shown to alter thyroid homeostasis. The aim of this longitudinal study was to measure plasma level of PBDEs in workers at an electronic recycling facility and to relate these to the workers’ thyroid status. Methods: PBDEs and three thyroid hormones: triiodothyronine (T3), thyroxin (T4) and thyroid stimulating hormone (TSH) were repeatedly analysed in plasma from 11 workers during a period of 1.5 years.Results: Plasma levels of PBDEs at start of employment were <0.5–9.1 pmol/g lipid weight (l.w.). The most common congener was PBDE #47 (median 2.8 pmol/g l.w.), followed by PBDE #153 (median 1.7 pmol/g l.w.), and PBDE #183 had a median value of <0.19 pmol/g l.w. After dismantling the corresponding median concentrations were: 3.7, 1.7 and 1.2 pmol/g l.w., respectively. These differences in PBDE levels were not statistically significant. PBDE #28 showed a statistically significantly higher concentration after dismantling than at start of employment (P=0.016), although at low concentrations (start 0.11 pmol/g l.w. and dismantling 0.26 pmol/g l.w.). All measured levels of thyroid hormones (T3, T4 and TSH) were within the normal physiological range. Statistically significant positive correlations were found between T3 and #183 in a worker, between T4 and both #28 and #100 in another worker and also between TSH and #99 and #154 in two workers. Conclusions: The workers’ plasma levels of PBDEs fluctuated during the study period. Due to small changes in thyroid hormone levels it was concluded that no relevant changes were present in relation to PBDE exposure within the workers participating in this study.

    National Category
    Environmental Sciences Chemical Sciences
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-3144 (URN)10.1007/s00420-005-0627-5 (DOI)15902483 (PubMedID)
    Available from: 2006-10-13 Created: 2006-10-13 Last updated: 2017-12-14Bibliographically approved
    3. Air levels of brominated flame retardants in an electronic dismantling facility after a production increase
    Open this publication in new window or tab >>Air levels of brominated flame retardants in an electronic dismantling facility after a production increase
    (English)Manuscript (preprint) (Other academic)
    National Category
    Environmental Sciences
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-3145 (URN)
    Available from: 2006-10-13 Created: 2006-10-13 Last updated: 2017-10-18Bibliographically approved
    4. Levels of brominated flame retardants in blood in relation to levels in household air and dust
    Open this publication in new window or tab >>Levels of brominated flame retardants in blood in relation to levels in household air and dust
    2007 (English)In: Environment International, ISSN 0160-4120, E-ISSN 1873-6750, Vol. 33, no 1, p. 62-69Article in journal (Refereed) Published
    Abstract [en]

    Levels of tri- to decabrominated diphenyl ethers (BDEs), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) and 1,2-bis(pentabromophenyl)ethane (DeBDethane) were determined in air, sedimentary dust and human plasma from five households in Sweden. The levels of the individual BDEs in the plasma samples were in the same order of magnitude as in other studies of the general population in Scandinavia, and varied between non-detectable (< 0.41 ng g− 1 l.w.) to 17 ng g− 1 (l.w.). BDE#28 and #47 were present in all air samples, with mean values of 0.015 and 0.12 ng m− 3, respectively, except for one sample where the BDE#47 concentration was below the limit of detection (< 0.17 ng m− 3). BDE#209 was found in one of the five air samples at a concentration of 0.26 ng m− 3. DeBDethane was also detected in one sample, in which the BDE#209 level was below LOD (< 0.021 ng m− 3), at a level of 0.023 ng m− 3. All the target compounds were found in the sedimentary dust samples at levels from 0.51 to 1600 ng g− 1, the highest concentration representing BDE#209. The most abundant components in plasma, air and dust were BDE#47, #99 and #209. In the plasma samples BDE#207 and #206 were also present at similar concentrations as BDE#47. In the sedimentary dust samples, DeBDethane was also among the most abundant BFRs. A positive relationship was found for the sumBDE concentrations in dust and plasma, although the relationship was strongly dependent on one of the five observations. BFR levels in dust and air were not dependent on the house characteristics such as living area, floor material or number of electronic devices.

    National Category
    Chemical Sciences Environmental Sciences
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-3146 (URN)10.1016/j.envint.2006.06.025 (DOI)
    Available from: 2006-10-13 Created: 2006-10-13 Last updated: 2017-12-14Bibliographically approved
    5. Levels of brominated flame retardants in Northern Fulmar (Fulmarus glacialis) eggs from the Faroe Islands
    Open this publication in new window or tab >>Levels of brominated flame retardants in Northern Fulmar (Fulmarus glacialis) eggs from the Faroe Islands
    Show others...
    2006 (English)In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 367, no 2-3, p. 840-846Article in journal (Refereed) Published
    Abstract [en]

    Eggs from Northern Fulmars (Fulmarus glacialis) were sampled in the Faroe Islands. The content of the brominated flame retardants tri- to decabromodiphenyl ethers (BDEs) and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) were determined in nine samples in concentrations ranging from non-detectable to 7 ng g− 1(l.w.). The BDE levels were similar as in an earlier study of BDE levels in the fulmar eggs from the Faroe Islands but 10–1000 times lower compared to studies of eggs from seabirds and birds of prey from Europe. The two hexaBDEs #153 and #154 were the most abundant congeners, which represented around 50% of the total mean BDE concentration. The levels of BDE #209 were below the limit of detection (1.24 ng g− 1 l.w.) except for one sample, which showed a concentration of 7.18 ng g− 1 l.w. BTBPE was detected in eight samples and the mean level was 0.11 ng g− 1 l.w. This concentration was 150 times lower than the average total BDE concentration (including BDEs #28, #47, #100, #99, #154, #153, #183, #209). BTBPE has only been detected once before in biota. Also other bromo-containing compounds were detected in the fulmar eggs. One group identified was the polybrominated biphenyls (PBBs), but because of the absence of reference standards in the lab, these could not be quantified.

    National Category
    Chemical Sciences
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-3147 (URN)10.1016/j.scitotenv.2006.02.050 (DOI)
    Available from: 2006-10-13 Created: 2006-10-13 Last updated: 2017-12-14Bibliographically approved
  • 167.
    Karlsson, Marie
    et al.
    Örebro University, Department of Natural Sciences.
    Ericson, I.
    van Bavel, Bert
    Örebro University, Department of Natural Sciences.
    Jensen, J.-K.
    Dam, M.
    Levels of brominated flame retardants in Northern Fulmar (Fulmarus glacialis) eggs from the Faroe Islands2006In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 367, no 2-3, p. 840-846Article in journal (Refereed)
    Abstract [en]

    Eggs from Northern Fulmars (Fulmarus glacialis) were sampled in the Faroe Islands. The content of the brominated flame retardants tri- to decabromodiphenyl ethers (BDEs) and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) were determined in nine samples in concentrations ranging from non-detectable to 7 ng g− 1(l.w.). The BDE levels were similar as in an earlier study of BDE levels in the fulmar eggs from the Faroe Islands but 10–1000 times lower compared to studies of eggs from seabirds and birds of prey from Europe. The two hexaBDEs #153 and #154 were the most abundant congeners, which represented around 50% of the total mean BDE concentration. The levels of BDE #209 were below the limit of detection (1.24 ng g− 1 l.w.) except for one sample, which showed a concentration of 7.18 ng g− 1 l.w. BTBPE was detected in eight samples and the mean level was 0.11 ng g− 1 l.w. This concentration was 150 times lower than the average total BDE concentration (including BDEs #28, #47, #100, #99, #154, #153, #183, #209). BTBPE has only been detected once before in biota. Also other bromo-containing compounds were detected in the fulmar eggs. One group identified was the polybrominated biphenyls (PBBs), but because of the absence of reference standards in the lab, these could not be quantified.

  • 168.
    Karlsson, Marie
    et al.
    Örebro University, Department of Natural Sciences.
    Julander, Anneli
    Örebro University, Department of Natural Sciences.
    van Bavel, Bert
    Örebro University, Department of Natural Sciences.
    Air levels of brominated flame retardants in an electronic dismantling facility after a production increaseManuscript (preprint) (Other academic)
  • 169.
    Karlsson, Marie
    et al.
    Örebro University, Department of Natural Sciences.
    Julander, Anneli
    Örebro University, Department of Natural Sciences.
    van Bavel, Bert
    Örebro University, Department of Natural Sciences.
    Hardell, Lennart
    Levels of brominated flame retardants in blood in relation to levels in household air and dust2007In: Environment International, ISSN 0160-4120, E-ISSN 1873-6750, Vol. 33, no 1, p. 62-69Article in journal (Refereed)
    Abstract [en]

    Levels of tri- to decabrominated diphenyl ethers (BDEs), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) and 1,2-bis(pentabromophenyl)ethane (DeBDethane) were determined in air, sedimentary dust and human plasma from five households in Sweden. The levels of the individual BDEs in the plasma samples were in the same order of magnitude as in other studies of the general population in Scandinavia, and varied between non-detectable (< 0.41 ng g− 1 l.w.) to 17 ng g− 1 (l.w.). BDE#28 and #47 were present in all air samples, with mean values of 0.015 and 0.12 ng m− 3, respectively, except for one sample where the BDE#47 concentration was below the limit of detection (< 0.17 ng m− 3). BDE#209 was found in one of the five air samples at a concentration of 0.26 ng m− 3. DeBDethane was also detected in one sample, in which the BDE#209 level was below LOD (< 0.021 ng m− 3), at a level of 0.023 ng m− 3. All the target compounds were found in the sedimentary dust samples at levels from 0.51 to 1600 ng g− 1, the highest concentration representing BDE#209. The most abundant components in plasma, air and dust were BDE#47, #99 and #209. In the plasma samples BDE#207 and #206 were also present at similar concentrations as BDE#47. In the sedimentary dust samples, DeBDethane was also among the most abundant BFRs. A positive relationship was found for the sumBDE concentrations in dust and plasma, although the relationship was strongly dependent on one of the five observations. BFR levels in dust and air were not dependent on the house characteristics such as living area, floor material or number of electronic devices.

  • 170.
    Karlsson, Marie
    et al.
    Örebro University, Department of Natural Sciences.
    Julander, Anneli
    Örebro University, Department of Natural Sciences.
    van Bavel, Bert
    Örebro University, Department of Natural Sciences.
    Lindström, Gunilla
    Örebro University, Department of Natural Sciences.
    Solid-phase extraction of polybrominated diphenyl ethers in human plasma: comparison with an open column extraction method2005In: Chromatographia, ISSN 0009-5893, E-ISSN 1612-1112, Vol. 61, no 1-2, p. 67-73Article in journal (Refereed)
    Abstract [en]

    A solid phase extraction (SPE) method in combination with silica gel cleanup to analyse tri-to heptabrominated diphenyl ethers in human plasma was validated. All congeners showed recoveries over 70% except for BDE #183, which showed recoveries around 45%. The method was tested on 21 individual plasma samples which were extracted with both the SPE method and an open column extraction method using Hydromatrix. Method detection limits were of the same order of magnitude for both methods, ranging from 0.0076 to 0.13 ng g−1 (l.w.) depending on the congener. The SPE extraction method meets the demand for a faster, less solvent-and sample-demanding method with lower contamination risk due to fewer steps compared to the open column extraction.

  • 171.
    Karlsson, Stefan
    et al.
    Örebro University, Department of Natural Sciences.
    Allard, Bert
    Örebro University, Department of Natural Sciences.
    Bäckström, Mattias
    Örebro University, Department of Natural Sciences.
    Changes in hydrochemistry some 15 years after covering of sulphidic mine waste, Bersbo, Sweden2005In: Securing the future: international conference on mining and the environment, metals and energy recovery : proceedings, 2005, p. 509-518Conference paper (Refereed)
  • 172.
    Karlsson, Stefan
    et al.
    Örebro University, Department of Natural Sciences.
    Bäckström, Mattias
    Örebro University, Department of Natural Sciences.
    Surface water quality in Bersbo, Sweden: fifteen years after amelioration of sulphidic waste2003Conference paper (Refereed)
  • 173.
    Karlsson, Stefan
    et al.
    Örebro University, Department of Natural Sciences.
    Düker, Anders
    Örebro University, Department of Natural Sciences.
    Grahn, Evastina
    Örebro University, Department of Natural Sciences.
    Sediment chronologies of As, Bi, and Ga in Sweden - impact of industrialisation2007In: Journal of Environmental Science and Health. Part A: Toxic/Hazardous Substances and Environmental Engineering, ISSN 1093-4529, E-ISSN 1532-4117, Vol. 42, no 2, p. 155-164Article in journal (Refereed)
    Abstract [en]

    The acid-leachable amount and pore water concentration of As, Bi and Ga in sediment cores from four remote lakes in a south to north transect in Sweden were used to recapitulate the pollution history of the elements. The diagenetic impact on the element distribution was elucidated from their solid/solution partition and relationships to elements indicative for diagenesis. Dating was made by their acid-leachable lead content in combination with the Pb-206/Pb-207 ratio. In one of the lakes this approach was validated against dating with Pb-210. The impact of diagenesis on the sediment distribution of theses elements was found to be low enough for a chronological interpretation of the sediment profiles, as evidenced by their ratios to elements indicative of the geological background. A closer examination of the diagenetic impact would however be required if a more detailed chronology is desired. This study has demonstrated that atmospheric deposition of arsenic, bismuth and gallium contributes to the sediment inventory of these elements. The major part of the deposition of arsenic and bismuth took place after the Second World War. For gallium no concentrations exceeding background were detected before circa 1930. Increased levels of arsenic are traceable to circa 1850. For bismuth increased levels are concluded to extend before 1790, i.e., background concentrations were not reached in the present cores. For all elements the atmospheric deposition has been lower towards the north.

  • 174.
    Karlsson, Stefan
    et al.
    Örebro University, Department of Natural Sciences.
    Grahn, Evastina
    Örebro University, Department of Natural Sciences.
    Düker, Anders
    Örebro University, Department of Natural Sciences.
    Bäckström, Mattias
    Örebro University, Department of Natural Sciences.
    Historical pollution of seldom monitored trace elements in Sweden - Part A: sediment properties and chronological indicators2006In: Journal of Environmental Monitoring, ISSN 1464-0325, E-ISSN 1464-0333, Vol. 8, no 7, p. 721-731Article in journal (Refereed)
    Abstract [en]

    Sediment cores from four small oligotrophic boreal lakes, with minor acidification, in remote regions of central Sweden were used for historical interpretation of their metal content, with focus on Cu, Cd, Pb and Zn in Lake Stensjön, which has the longest sediment record (at least two centuries according to 210Pb dating). Comparison is made with the other three lakes. Major and trace elements in lake water, porewater and the acid-leached (HNO3) solid sediment phase was analysed with ICP-MS. In addition, general lake water chemistry, TOC and principal anions were measured in the aqueous phases. Redistribution processes were interpreted from geochemical modelling. The solid/solution distribution of pe/pH sensitive elements, indicates a minor diagenetic redistribution and the concentration profiles are therefore suitable for chronological evaluation. The ratios of Al, Ti, Sc and V, indicated a qualitative shift of sedimenting material a century ago, which did not have any impact on the retention of trace elements. Lead had a concentration profile, supported by the 206Pb/207Pb ratio, where it was possible to distinguish preindustrial conditions, early industrialisation in Europe, industrialisation in Sweden, and the use of leaded petrol after the Second World War. Cadmium showed a similar concentration pattern. The zinc profile resembled that of cadmium, but with less enrichment. Local lithogenic sources are believed to be quantitatively important. The solid/solution distribution (Kd) was independent of depth for all four elements. The sediment concentrations of copper and zinc are not related to early industrialisation but its concentration has doubled since the Second World War.

  • 175.
    Karlsson, Ulrika
    Örebro University, Department of Natural Sciences.
    Environmental levels of thallium: influence of redox properties and anthropogenic sources2006Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Thallium is a highly toxic element that humans are exposed to mainly by consumption of drinking water and vegetables grown in soil with high thallium content but also through inhalation of particles in the air. Thallium is also present in fossil fuels, alloys, and in electronic utilities. The increasing use of the element and emissions from notably energy production has lead to a higher load on the surface of the Earth. This study aims at increasing the knowledge about the behaviour of thallium in aquatic environments. Focus has been on the redox chemistry of thallium in relation to its mobility, which is of great importance because Tl(I) and Tl(III) have very different properties in this respect.

    The relationship between Tl(I) and Tl(III) in surface waters from contaminated and uncontaminated environments was examined by ion chromatography connected on line to ICP-MS (inductively coupled plasma mass spectrometry). It was found in controlled systems that even though Tl(III) is thermodynamically unstable under fresh water conditions Tl(I) was oxidised in the presence of light and iron(III). This was also confirmed in field studies. When lake water samples were exposed to light, Tl(I) was oxidised and thallium was lost from the solution. The most likely explanation for this was adsorption of thallium to particle surfaces.

    The concentration of thallium in Swedish lakes and soil were measured. In unpolluted lakes the concentration ranges between 4.5-12 ng/l, the sediment concentration was 0.07-1.46 mg/kg. The anthropogenic load was found to have increased since the end of the Second World War although concentrations above background were found since the early industrialisation. In contaminated areas the concentration in soil ranges from 0.64-88 mg/kg, high concentrations were found in systems with alum shale and in soil exposed to runoff from a lead and zinc enrichment plant.

    The mobilisation of thallium from solid phases in contaminated areas was dependent on pH and about 50% of the leachable content was mobilised already at pH 5-6. Once it had been released to water it was highly mobile. These conditions suggest that in a large part of the Swedish environment a high mobility of thallium can be expected.

    List of papers
    1. Historical pollution of seldom monitored trace elements in Sweden: Part B: sediment analysis of silver, antimony, thallium and indium
    Open this publication in new window or tab >>Historical pollution of seldom monitored trace elements in Sweden: Part B: sediment analysis of silver, antimony, thallium and indium
    2006 (English)In: Journal of Environmental Monitoring, ISSN 1464-0325, E-ISSN 1464-0333, Vol. 8, no 7, p. 732-744Article in journal (Refereed) Published
    Abstract [en]

    Sediment cores from four boreal and remote lakes in a south to north transect in central Sweden were analysed for acid leachable silver, antimony, thallium and indium in the solid sediment phase and the corresponding porewater. Dating of the cores was made by their content of acid leachable lead and the 206Pb/207Pb ratio, in one lake also by 210Pb. The impact of diagenesis on element redistribution in the sediments was included and found to be minor except for thallium. The results show lowered concentrations towards the north and most intense accumulation after the Second World War, which is taken as evidence for atmospheric deposition being the primary source. Indium has declining concentrations in recent strata while silver and antimony increase. Thallium has lowered acid-leachable concentrations in recent strata. For all metals the impact of domestic industrialisation as well as the early industrialisation of central Europe is discernible. Only thallium appears to reach a geological background at depths that correspond to the late 18th century. For the other metals elevated levels are concluded.

    National Category
    Environmental Sciences Chemical Sciences
    Research subject
    Enviromental Science
    Identifiers
    urn:nbn:se:oru:diva-3053 (URN)10.1039/B601948J (DOI)
    Available from: 2006-03-09 Created: 2006-03-09 Last updated: 2017-12-14Bibliographically approved
    2. Assessing the release of thallium, cadmium, lead, copper and zinc from deposits with mixed wastes: a case study
    Open this publication in new window or tab >>Assessing the release of thallium, cadmium, lead, copper and zinc from deposits with mixed wastes: a case study
    (English)Manuscript (Other academic)
    National Category
    Chemical Sciences
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-3054 (URN)
    Available from: 2006-03-09 Created: 2006-03-09 Last updated: 2017-10-18Bibliographically approved
    3. Hydrogeochemical interpretations of a fly ash/municipal sludge covered sulphidic mine waste deposit: a case study of alkaline leachates in an acidic environment
    Open this publication in new window or tab >>Hydrogeochemical interpretations of a fly ash/municipal sludge covered sulphidic mine waste deposit: a case study of alkaline leachates in an acidic environment
    (English)Manuscript (Other academic)
    National Category
    Chemical Sciences
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-3055 (URN)
    Available from: 2006-03-09 Created: 2006-03-09 Last updated: 2017-10-18Bibliographically approved
    4. Separation and quantification of Tl(I) and Tl(III) in fresh water samples
    Open this publication in new window or tab >>Separation and quantification of Tl(I) and Tl(III) in fresh water samples
    2006 (English)In: Journal of Environmental Science and Health. Part A: Toxic/Hazardous Substances and Environmental Engineering, ISSN 1093-4529, E-ISSN 1532-4117, Vol. 41, no 7, p. 1155-1167Article in journal (Refereed) Published
    Abstract [en]

    The two oxidation states of thallium, Tl(I) and Tl(III), were quantified by IC-ICP-MS using complexation of Tl3+ with DTPA (penta-carboxymethyl-diethylenetriamine) and separation on a cation exchange column according to a modification of the method devised by Coetzee et al. In order to avoid successively lowered separation efficiency and loss of resolution during a run, a gradient elution was made using HCl instead of HNO3. With an ultrasonic nebuliser instead of a V-groove nebuliser the limit of detection for Tl(I) and Tl(III) could be lowered from 25 ng/L and 3.0 ng/L to 9.0 ng/L and 0.7 ng/L, respectively, which is adequate for many fresh water systems. The stability of Tl(III) in acidic solutions was found to be concentration dependent, with an initially high reduction rate of Tl(III). Exposure of the sample to light further increased the reduction rate. Addition of DTPA (0.01 mM) and acid (HNO3, 1%) to a sample with 1 μg/L Tl(III) stabilised the Tl(III) content for at least 48 h. Analysis of field samples showed that only acidification is inadequate to maintain the original distribution of Tl(I) and Tl(III). Internal calibration (standard addition) and correction of the analytical signal (205Tl) with a non-ionic internal standard (11B) yielded almost quantitative recoveries of both Tl(I) and Tl(III). A scheme for field sample preparation is proposed, including sampling, storage and pre-analysis treatment.

    National Category
    Chemical Sciences
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-3056 (URN)10.1080/10934520600655747 (DOI)
    Available from: 2006-03-09 Created: 2006-03-09 Last updated: 2017-12-14Bibliographically approved
    5. The effect of light and iron(II)/iron(III) on the distribution of Tl(I)/Tl(III) in fresh water systems
    Open this publication in new window or tab >>The effect of light and iron(II)/iron(III) on the distribution of Tl(I)/Tl(III) in fresh water systems
    2006 (English)In: Journal of Environmental Monitoring, ISSN 1464-0325, E-ISSN 1464-0333, Vol. 8, no 6, p. 634-640Article in journal (Refereed) Published
    Abstract [en]

    The distribution of aqueous Tl(I)/Tl(III) as a function of light exposure and solution properties was studied by quantifying the oxidation states after separation with ion chromatography and on-line detection with ICP-MS. Ultraviolet irradiation of aqueous solutions containing 1 μg l−1 Tl(III) and in equilibrium with the atmosphere increases the reduction rate. In systems with photoreduction of Fe(III)(aq) a quantitative oxidation of Tl(I)(aq) was observed, notably at low pH. The process is reversible, as indicated by formation of Tl(I) when the irradiated systems were kept in the dark. In systems with colloidal silica-stabilised ferrihydrite, UV irradiation also leads to oxidation of Tl(I)(aq), but not quantitatively. It is suggested that adsorption of thallium to the ferrihydrite determines the rate of oxidation. Detectable, but not quantitative, oxidation of Tl(I)(aq) took place when natural water samples with 1 μg l−1 Tl(I)(aq) were exposed to either sunlight or UV-light. For these samples, the reduction was not quantitative when they were kept in the dark for 24 h. The results suggest that the light dependent iron cycle in fresh water systems strongly influences the redox state of thallium.

    National Category
    Environmental Sciences
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-3057 (URN)10.1039/B516445A (DOI)
    Available from: 2006-03-09 Created: 2006-03-09 Last updated: 2017-12-14Bibliographically approved
  • 176.
    Karlsson, Ulrika
    et al.
    Örebro University, Department of Natural Sciences.
    Düker, Anders
    Örebro University, Department of Natural Sciences.
    Karlsson, Stefan
    Örebro University, Department of Natural Sciences.
    Separation and quantification of Tl(I) and Tl(III) in fresh water samples2006In: Journal of Environmental Science and Health. Part A: Toxic/Hazardous Substances and Environmental Engineering, ISSN 1093-4529, E-ISSN 1532-4117, Vol. 41, no 7, p. 1155-1167Article in journal (Refereed)
    Abstract [en]

    The two oxidation states of thallium, Tl(I) and Tl(III), were quantified by IC-ICP-MS using complexation of Tl3+ with DTPA (penta-carboxymethyl-diethylenetriamine) and separation on a cation exchange column according to a modification of the method devised by Coetzee et al. In order to avoid successively lowered separation efficiency and loss of resolution during a run, a gradient elution was made using HCl instead of HNO3. With an ultrasonic nebuliser instead of a V-groove nebuliser the limit of detection for Tl(I) and Tl(III) could be lowered from 25 ng/L and 3.0 ng/L to 9.0 ng/L and 0.7 ng/L, respectively, which is adequate for many fresh water systems. The stability of Tl(III) in acidic solutions was found to be concentration dependent, with an initially high reduction rate of Tl(III). Exposure of the sample to light further increased the reduction rate. Addition of DTPA (0.01 mM) and acid (HNO3, 1%) to a sample with 1 μg/L Tl(III) stabilised the Tl(III) content for at least 48 h. Analysis of field samples showed that only acidification is inadequate to maintain the original distribution of Tl(I) and Tl(III). Internal calibration (standard addition) and correction of the analytical signal (205Tl) with a non-ionic internal standard (11B) yielded almost quantitative recoveries of both Tl(I) and Tl(III). A scheme for field sample preparation is proposed, including sampling, storage and pre-analysis treatment.

  • 177.
    Karlsson, Ulrika
    et al.
    Örebro University, Department of Natural Sciences.
    Karlsson, Stefan
    Örebro University, Department of Natural Sciences.
    Düker, Anders
    Örebro University, Department of Natural Sciences.
    The effect of light and iron(II)/iron(III) on the distribution of Tl(I)/Tl(III) in fresh water systems2006In: Journal of Environmental Monitoring, ISSN 1464-0325, E-ISSN 1464-0333, Vol. 8, no 6, p. 634-640Article in journal (Refereed)
    Abstract [en]

    The distribution of aqueous Tl(I)/Tl(III) as a function of light exposure and solution properties was studied by quantifying the oxidation states after separation with ion chromatography and on-line detection with ICP-MS. Ultraviolet irradiation of aqueous solutions containing 1 μg l−1 Tl(III) and in equilibrium with the atmosphere increases the reduction rate. In systems with photoreduction of Fe(III)(aq) a quantitative oxidation of Tl(I)(aq) was observed, notably at low pH. The process is reversible, as indicated by formation of Tl(I) when the irradiated systems were kept in the dark. In systems with colloidal silica-stabilised ferrihydrite, UV irradiation also leads to oxidation of Tl(I)(aq), but not quantitatively. It is suggested that adsorption of thallium to the ferrihydrite determines the rate of oxidation. Detectable, but not quantitative, oxidation of Tl(I)(aq) took place when natural water samples with 1 μg l−1 Tl(I)(aq) were exposed to either sunlight or UV-light. For these samples, the reduction was not quantitative when they were kept in the dark for 24 h. The results suggest that the light dependent iron cycle in fresh water systems strongly influences the redox state of thallium.

  • 178.
    Karlsson, Ulrika
    et al.
    Örebro University, Department of Natural Sciences.
    Karlsson, Stefan
    Örebro University, Department of Natural Sciences.
    Düker, Anders
    Bäckström, Mattias
    Assessing the release of thallium, cadmium, lead, copper and zinc from deposits with mixed wastes: a case studyManuscript (Other academic)
  • 179. Keiter, Steffen
    et al.
    Grund, Stefanie
    van Bavel, Bert
    Örebro University, Department of Natural Sciences.
    Hagberg, Jessika
    Örebro University, Department of Natural Sciences.
    Engwall, Magnus
    Örebro University, Department of Natural Sciences.
    Kammann, Ulrike
    Klempt, Martin
    Manz, Werner
    Olsman Takner, Helena
    Örebro University, Department of Natural Sciences.
    Braunbeck, Thomas
    Hollert, Henner
    Activities and identification of aryl hydrocarbon receptor agonists in sediments from the Danube river2008In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 390, no 8, p. 2009-2019Article in journal (Refereed)
    Abstract [en]

    This study is a consequence of a distinct fish decline in the Danube river since the beginning of the 1990s. In contrast to the decline of fish population, former studies have repeatedly documented that the water quality along the Danube river is improving. However, the conclusion of a pilot study in 2002 was that a high hazard potential is associated with local sediments. The present study documents that sediment samples from the Danube river showed comparatively high aryl hydrocarbon receptor mediated activity in biotests, using the cell lines GPC.2D.Luc, H4IIE (DR-CALUX®) and RTL-W1. The combination of chemical analysis, fractionation techniques and different in vitro tests revealed that priority pollutants could not explain the main induction, even though the concentrations of priority polycyclic aromatic hydrocarbons (PAHs) were very high (maximum in the tributary Schwarzach, sum of 16 EPA PAHs 26 μg/g). In conclusion, this investigation shows that nonpriority pollutants mainly mediate the high induction rates. Nevertheless, owing to the effects of PAHs towards fish and the connection between dioxin-like activity and carcinogenicity, the link between contamination and the fish population decline cannot be ruled out.

  • 180.
    Keiter, Steffen
    et al.
    University of Heidelberg, Heidelberg, Germany.
    Grund, Stefanie
    University of Heidelberg, Heidelberg, Germany.
    van Bavel, Bert
    Örebro University, Department of Natural Sciences.
    Hagberg, Jessika
    Örebro University, Department of Natural Sciences.
    Engwall, Magnus
    Örebro University, Department of Natural Sciences.
    Ulrike, Kammann
    Federal Research Centre for Fisheries, Hamburg, Germany.
    Klempt, Martin
    Federal Research Centre for Nutrition and Food, Hamburg, Germany.
    Manz, Werner
    Federal Institute of Hydrology, Koblenz, Germany.
    Olsman, Helena
    Örebro University, Department of Natural Sciences.
    Braunbeck, Thomas
    University of Heidelberg, Heidelberg, Germany.
    Hollert, Henner
    RWTH Aachen University, Aachen, Germany .
    Activities and identification of aryl hydrocarbon receptor agonists in sediments from the Danube river2008In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 390, no 8, p. 2009-2019Article in journal (Refereed)
    Abstract [en]

    This study is a consequence of a distinct fishdecline in the Danube river since the beginning of the 1990s. In contrast to the decline of fish population, former studies have repeatedly documented that the water quality along the Danube river is improving. However, the conclusion of a pilot study in 2002 was that a high hazard potentialis associated with local sediments. The present study documents that sediment samples from the Danube river showed comparatively high aryl hydrocarbon receptor mediated activity in biotests, using the cell lines GPC.2D.Luc, H4IIE(DR-CALUX®) and RTL-W1. The combination of chemical analysis, fractionation techniques and different in vitro tests revealed that priority pollutants could not explain the main induction, even though the concentrations of prioritypolycyclic aromatic hydrocarbons (PAHs) were very high (maximum in the tributary Schwarzach, sum of 16 EPAPAHs 26 μg/g). In conclusion, this investigation shows that nonpriority pollutants mainly mediate the high inductionrates. Nevertheless, owing to the effects of PAHs towards fish and the connection between dioxin-like activity andcarcinogenicity, the link between contamination and the fish population decline cannot be ruled out.

  • 181.
    Kempi, Michael
    Örebro University, Department of Natural Sciences.
    Sluttäckningsförsök med flygaskastabiliserat avloppsslam (FSA 53) som tätskikt på Atleverkets deponi i Örebro2006Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Abstract

    This master thesis was performed for Atleverket, Technical departement, municipality of Örebro, Sweden in cooperation with the institution of natural sciences at the University of Örebro. The master thesis involved a project in which a test area of the waste deposit of Atleverket, was to be sealed by a top-sealing construction. The construction is a preparation for a large-scale sealing according to new legislation and guidelines authorized by the swedish governement, through the Naturvårdsverket, and the European Union.

    The thesis consists of a theoretical part, in which litterature studies and studies of the physical processes involved in a waste deposit occurred and a practical part, where construction material were tested and a test area was constructed.

    The litterature study consisted of interpretation of the current research in the field and an attempt to applicate the environmental physics models on the local parameters. In the practical part, the local waste bi-products, flyash and yeasted sewage, which were to be used as a non-percolating sealing layer, were examined. Furthermore, strictly technical construction aspects and project management were included in the thesis and are well documented as an appendix.

    The results from field measurement and laboratory were processed with mathematical, statistical theories, in order to determine whether the results could prove the test area and construction materials to be homogenous. Another aspect is whether the theoretical model-simulations would prove applicable in reality.

    The results show that (by July 2006) FSA 55, flyashstabilized yeasted sewage, shows the behaviours as a material needs, as a sealing liner in a top-sealing construction. However, numerous questions remains, among which consists of the life-time of the material and if the top-sealing strategy is the optimum strategy for waste processing.

    Further reaserch in the field is necessary, foremost the long-term effects.

  • 182. Klee, Nina
    et al.
    Gustavsson, Lillemor
    Örebro University, Department of Natural Sciences.
    Kosmehl, Thomas
    Engwall, Magnus
    Örebro University, Department of Natural Sciences.
    Erdinger, Lothar
    Braunbeck, Thomas
    Hollert, Henner
    Changes in toxicity and genotoxicity of industrial sewage sludge samples containing nitro- and amino-aromatic compounds following treatment in bioreactors with different oxygen regimes2004In: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 11, no 5, p. 313-320Article in journal (Refereed)
    Abstract [en]

    GOALS, SCOPE AND BACKGROUND: From 2005, deposition of organic waste will be banned in Sweden. Likewise, in Germany and Austria, similar bans are being planned, and further countries will probably follow. Thus, there is a need to develop new methods and to refine established techniques for sludge management in the whole of the European Union. For this end, there is also an urgent need for appropriate ecotoxicological approaches to elucidate and assess the hazard potential of sewage sludge. Therefore, the present study was designed to assess the capacity of various established sludge treatment methods using different oxygen regimes to degrade recalcitrant nitro-substituted organic compounds and reduce their toxicity. Sewage sludge samples from a wastewater treatment plant in Sweden (Cambrex Karlskoga AB, industrial area Björkborn) receiving wastewater from industries manufacturing pharmaceutical substances, chemical intermediates and explosives were processed with different sludge treatment methods. Among other treatment methods, bioreactors (for anaerobic and aerobic sludge treatment) were used. In the present investigation, a battery of in vitro bioassays was employed to compare the cytotoxic and genotoxic potentials of different fractions of sludge samples in order to elucidate whether the treatments were suitable to reduce the toxicity of the sludge.

    METHODS:

    In order to investigate the cytotoxicity of the extracts of treated and untreated sludge samples, the acute cytotoxicity test with the permanent cell line RTL-W1 was used. Genotoxicity was tested by means of the comet assay (single cell gel electrophoresis) with RTL-W1 cells, and mutagenicity was assessed with the Ames test using the Salmonella typhimurium strains TA98, TA98NR and TA100. Sludge toxicity was tested in different fractions of organic extracts produced by acetone and hexane extractions. The subsequent clean-up procedure (silica gel chromatography and elution with hexane and dichloromethane) resulted in two fractions, a lipophilic hexane-fraction and a semi-lipophilic dichloromethane-fraction. For the genotoxicity and mutagenicity tests, these fractions were reunited at equal ratios.

    RESULTS AND DISCUSSION:

    The acute cytotoxicity test with RTL-W1 cells revealed a high cytotoxic potential for the semi-lipophilic DM-fractions of all sludge samples with NR50 values (= effective concentration for 50% cell death in the neutral red test) from 8.9 up to 20 mg sludge d.w./ml medium. A low cytotoxic potential for the hexane fractions of the untreated sludge samples (NR50 400 to > 400 mg sludge d.w./ml medium) was observed, whereas the hexane fractions of the treated sludge samples showed elevated cytotoxicity increasing further with treatment in the bioreactors. The comet assay indicated that three out of eight of the reunited fractions had a significant genotoxic potential. Whereas the genotoxic potential of one sample treated anaerobically was very high with an induction factor of 11.6, a similar sample (taken from the same anaerobic reactor four months later) and one untreated sample showed lower potentials. The samples treated in another anaerobic bioreactor as well as the samples treated aerobically showed no genotoxic potential. Results indicate that aerobic treatment was basically adequate for reducing the genotoxicity of the sludge, whereas anaerobic treatment was only partly useful for reduction of genotoxicity. The Ames test revealed a very high mutagenic potential for the reunited fractions of the untreated sludge samples with strain TA98 (maximum induction factors (IFmax) up to 45) and a relatively high potential for one of the samples treated aerobically (S2, IFmax = 18 (TA98, S9-)), thus documenting the suitability of both anaerobic and aerobic treatments to reduce the mutagenicity of the samples, however, with the aerobic treatment being less effective.

    CONCLUSIONS:

    Overall, none of the microbiological treatments for wastewater sludge in bioreactors was found to be ideal for general toxicity reduction of the sludge samples. Whereas cytotoxicity of the sludge increased or levelled off in most cases following either treatment, genotoxicity both increased or decreased after anaerobic treatment, depending on the specific sample. However, mutagenicity could generally be reduced by anaerobic treatment and, to a lesser degree, by aerobic treatment.

    RECOMMENDATIONS AND PERSPECTIVES:

    The complex modification of the diverse damage potentials of sludge sample extracts by use of an in vitro biotest battery following treatment for toxicity reduction in bioreactors showed that considerations of different toxicological endpoints is essential for an adequate hazard assessment. Whereas in the case of cytotoxicity reduction, the reactors proved ineffective, mutagenicity could be reduced significantly at least in some cases in this case study.

  • 183. Knudsen, Lisa B.
    et al.
    Borgå, Katrine
    Jørgensen, Even H.
    van Bavel, Bert
    Örebro University, Department of Natural Sciences.
    Schlabach, Martin
    Verreault, Jonathan
    Gabrielsen, Geir W.
    Halogenated organic contaminants and mercury in northern fulmars (Fulmarus glacialis): levels, relationships to dietary descriptors and blood to liver comparison2007In: Environmental Pollution, ISSN 0269-7491, E-ISSN 1873-6424, Vol. 146, no 1, p. 25-33Article in journal (Refereed)
    Abstract [en]

    The northern fulmar (Fulmarus glacialis) is an interesting candidate for the study of patterns and levels of halogenated organic contaminants (HOCs) since they accumulate high levels of certain HOCs. In the present study we characterized a suite of established and novel HOCs in northern fulmars breeding on Bjørnøya in the Norwegian Arctic. A comparison between blood and liver HOC levels was made, and the levels were related to the ratios of heavier to lighter stable isotopes of nitrogen (15)N/(14)N (delta(15)N) and carbon (13)C/(12)C (delta(13)C) in muscle. A significant difference in congener patterns between blood and liver was found. The delta(13)C was not related to HOCs, neither in liver nor in blood. Weak correlations were found between delta(15)N and liver HOC levels. The 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents (TEQs) in northern fulmars were well above thresholds for reproductive effects in seabirds.

  • 184.
    Kärrman, Anna
    Örebro University, Department of Natural Sciences.
    Analysis and human levels of persistent perfluorinated chemicals2006Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    An extensive use of perfluorinated chemicals (PFCs) in the last 50 years has resulted in a worldwide spread of these persistent chemicals. Human populations are subjected to a large number of PFCs in ways that are not yet fully explained. The aims of this thesis are to develop and assure the quality of analytical methods in order to collect information on human levels and to facilitate the assessment of human exposure of PFCs.

    Solid-phase extraction (SPE) methods for human blood and milk using two sorbents, octadecyl (C18) and a weak anion exchange polymer (WAX), were developed. Perfluorinated alkyl sulfonates (PFSAs) and perfluorinated alkyl carboxylic acids (PFCAs) with carbon chain lengths between four and fourteen together with perfluorooctane sulfonamide (PFOSA) could be extracted from human matrices. These extraction procedures enable selective and sensitive analysis of PFCs in human matrices using single quadrupole mass spectrometry (SQMS). The accuracy and reliability of the methods are discussed in the context of intralaboratory as well as interlaboratory quality assurance. Further improvements of the analysis are discussed including the evaluation of ultra performance liquid chromatography (UPLC).

    Human whole blood, plasma and serum from Sweden, Australia and the United Kingdom have been analysed. The blood matrix selection in the assessment and comparisons of human exposure to PFCs is crucial. Human plasma contains a high percentage of PFSAs and PFCAs. On the contrary, only about 20% of the total PFOSA content is present in plasma after removal of the red blood cells. Up to eleven persistent PFCs are detected in human blood, with detection levels between 0.1-0.5 ng/mL. A gender difference with higher serum levels for males is apparent. An age trend was observed for perfluorooctane sulfonate (PFOS) levels in serum from Australia. The levels found in Australian serum indicate that emissions from the PFC production facilities are of less importance for human exposure.

    Matched human milk and serum samples from Sweden show that milk levels of PFCs are about 1% of the maternal serum level. Up to five persistent PFCs are found in human milk from Sweden, with detection limits between 0.005-0.1 ng/mL, and the levels in Swedish pooled milk samples have remained constant between 1996 and 2004. A linear relationship between the maternal serum level and milk level was seen for PFOS and its shorter homologue perfluorohexane sulfonate (PFHxS). The daily intake of PFOS for a nursing infant in Sweden is estimated to be 121 ng/day if the maternal serum level is 20 ng/mL. Lactation is therefore a major exposure source for breast-fed infants.

    Monomethyl- and dimethyl-branched isomers of PFOS could be separated in human blood using high performance liquid chromatography (HPLC). Human plasma contains a smaller percentage of the linear PFOS compared to commercially available PFOS standard materials, which indicate isomer specific uptake and/or elimination. A difference in the isomer composition is also seen between the countries studied. Human blood from the UK and Australia have significantly lower amount of linear PFOS (59-60%) compared to Swedish blood (68%). This geographical variation suggests different human exposure sources and pathways.

    List of papers
    1. Development of a solid-phase extraction-HPLC/Single quadrupole MS method for quantification of perfluorochemicals in whole blood
    Open this publication in new window or tab >>Development of a solid-phase extraction-HPLC/Single quadrupole MS method for quantification of perfluorochemicals in whole blood
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    2005 (English)In: Analytical Chemistry, ISSN 0003-2700, E-ISSN 1520-6882, Vol. 77, no 3, p. 864-870Article in journal (Refereed) Published
    Abstract [en]

    A method for the determination of perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA) simultaneously with 10 closely related perfluorochemicals (PFCs) in human whole blood was developed and validated. PFOS and PFOA are used in various applications, for example, as surfactants and plastic additives, and are subject to environmental and health research due to their persistence. The main part of the data on PFCs in human blood is from serum samples, analyzed mainly by ion pair extraction followed by high-performance liquid chromatography (HPLC) and negative electrospray (ESI) tandem mass spectrometry (MS/MS). The analytical method developed here is suitable for human whole blood and involves solid-phase extraction (SPE) and HPLC negative electrospray single quadrupole mass spectrometry (HPLC/ES-MS). A whole blood aliquot was treated with formic acid and extracted on a octadecyl (C18) SPE column. The PFCs were isolated with methanol, and quantification was performed using single quadrupole mass spectrometry and perfluoroheptanoic acid as internal standard. Validation was performed in the range 0.3-194 ng/mL with recovery between 64 and 112% and limit of detection in the 0.1-0.5 ng/mL range for 11 of the 12 PFCs studied. We applied this method to 20 whole blood samples collected in 1997-2000 from the Swedish population in the ages 24-72. Eleven of the 12 PFCs were detected, and they were quantitatively and qualitatively confirmed using triple quadrupole LC/MS/MS analysis. PFOS, perfluorooctanesulfonamide, perfluorohexanesulfonate, PFOA and perfluorononanoic acid were quantified in all samples. In addition, perfluorohexanoic acid, perfluorodecanoic acid, perfluorodecanesulfonate, perfluoroundecanoic acid, perfluorododecanoic acid, and perfluorotetradecanoic acid were detected in some samples. This study shows that SPE and single quadrupole MS can be applied for extraction and quantification of PFCs in human whole blood, resulting in selectivity and low detection limits.

    National Category
    Environmental Sciences Chemical Sciences
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-3115 (URN)10.1021/ac049023c (DOI)
    Available from: 2006-09-22 Created: 2006-09-22 Last updated: 2017-12-14Bibliographically approved
    2. Struggle for quality in determination of perfluorinated contaminants in environmental and human samples
    Open this publication in new window or tab >>Struggle for quality in determination of perfluorinated contaminants in environmental and human samples
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    2006 (English)In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 40, no 24, p. 7854-7860Article in journal (Refereed) Published
    Abstract [en]

    The first worldwide interlaboratory study on the analyses of 13 perfluorinated compounds (PFCs) in three environmental and two human samples indicates a varying degree of accuracy in relation to the matrix or analyte determined. The ability of 38 participating laboratories from 13 countries to determine the analytes in the various matrices was evaluated by calculation of z-scores according to the Cofino model. The PFCs which were reported most frequently by the laboratories, and assessed with the most satisfactory agreement, were perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA). In general, the level of agreement between the participating laboratories decreased in the following order: PFC standard solution (76% satisfactory z-scores of <[2]1 for PFOS) < human blood (67%) < human plasma (63%) < fish liver extract (55%) < water (31%) < fish tissue (17%). This shows that relative good agreement between laboratories was obtained for the study of standard and human matrices. For the fish extract, most laboratories underestimated the actual PFOS concentration due to matrix effects. The results for the fish tissue and water are also poor, indicating that the extraction and cleanup steps require further improvement. It was concluded that the PFC determinations in various matrices are not yet fully mastered.

    National Category
    Environmental Sciences Chemical Sciences
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-3116 (URN)10.1021/es061052c (DOI)
    Available from: 2006-09-22 Created: 2006-09-22 Last updated: 2017-12-14Bibliographically approved
    3. Perfluorinated chemicals in relation to other persistent organic pollutants in human blood
    Open this publication in new window or tab >>Perfluorinated chemicals in relation to other persistent organic pollutants in human blood
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    2006 (English)In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 64, no 9, p. 1582-1591Article in journal (Refereed) Published
    Abstract [en]

    In order to evaluate blood levels of some perfluorinated chemicals (PFCs) and compare them to current levels of classical persistent organic pollutants (POPs) whole blood samples from Sweden were analyzed with respect to 12 PFCs, 37 polychlorinated biphenyls (PCBs), p,p'-dichlorodiphenyl-dichloroethylene (DDE), hexachlorobenzene (HCB), six chlordanes and three polybrominated diphenyl ethers (PBDEs). The median concentration, on whole blood basis, of the sum of PFCs was 20-50 times higher compared to the sum of PCBs and p,p'-DDE, 300-450 times higher than HCB, sum of chlordanes and sum of PBDEs. Estimations of the total body amount of PFCs and lipophilic POPs point at similar body burdens. While levels of for example PCBs and PBDEs are normalized to the lipid content of blood, there is no such general procedure for PFCs in blood. The distributions of a number of perfluorinated compounds between whole blood and plasma were therefore studied. Plasma concentrations were higher than whole blood concentrations for four perfluoroalkylated acids with plasma/whole blood ratios between 1.1 and 1.4, whereas the ratio for perflurooctanesulfonamide (PFOSA) was considerably lower (0.2). This suggests that the comparison of levels of PFCs determined in plasma with levels determined in whole blood should be made with caution. We also conclude that Swedish residents are exposed to a large number of PFCs to the same extent as in USA, Japan, Colombia and the few other countries from which data is available today.

    National Category
    Environmental Sciences Chemical Sciences
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-3117 (URN)10.1016/j.chemosphere.2005.11.040 (DOI)
    Available from: 2006-09-22 Created: 2006-09-22 Last updated: 2017-12-14Bibliographically approved
    4. Levels of 12 perfluorinated chemicals in pooled Australian serum, collected 2002-2003, in relation to age, gender, and region
    Open this publication in new window or tab >>Levels of 12 perfluorinated chemicals in pooled Australian serum, collected 2002-2003, in relation to age, gender, and region
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    2006 (English)In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 40, no 12, p. 3742-3748Article in journal (Refereed) Published
    Abstract [en]

    Pooled serum samples from 3802 Australian residents were analyzed for four perfluoroalkylsulfonates, seven perfluoroalkylcarboxylates, and perfluorooctanesulfonamide (PFOSA). Serum was collected from men and women of five different age groups and from rural and urban regions in Australia. The highest mean concentration was obtained for perfluorooctane sulfonate (PFOS, 20.8 ng/mL) followed by perfluorooctanoic acid (PFOA, 7.6 ng/mL), perfluorohexane sulfonate (PFHxS, 6.2 ng/mL), perfluorononanoic acid (PFNA, 1.1 ng/mL), and PFOSA (0.71 ng/mL). Additional four PFCs were detected in 5-18% of the samples at concentrations near the detection limits (0.1-0.5 ng/mL). An increase in PFOS concentration with increasing age in both regions and genders was observed. The male pool levels of some of the age groups compared to females were higherfor PFOS, PFOA, and PFHxS. In contrast, PFNA concentrations were higher in the female pools. No substantial difference was found in levels of PFCs between the urban and rural regions. The levels are equal or higher than previously reported serum levels in Europe and Asia but lower compared to the U.S.A. These results suggest that emissions from production in the Northern Hemisphere are of less importance for human exposure.

    National Category
    Environmental Sciences Chemical Sciences
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-3118 (URN)10.1021/es060301u (DOI)16830536 (PubMedID)
    Available from: 2006-09-22 Created: 2006-09-22 Last updated: 2017-12-14Bibliographically approved
    5. Analysis of perfluorooctane sulfonate (PFOS) isomers: identification and pattern in human blood from Sweden, the United Kingdom and Australia
    Open this publication in new window or tab >>Analysis of perfluorooctane sulfonate (PFOS) isomers: identification and pattern in human blood from Sweden, the United Kingdom and Australia
    Show others...
    (English)Manuscript (preprint) (Other academic)
    National Category
    Environmental Sciences Chemical Sciences
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-3119 (URN)
    Available from: 2006-09-22 Created: 2006-09-22 Last updated: 2017-10-18Bibliographically approved
    6. Exposure of perfluorinated chemicals through lactation: levels of matched human milk and serum and a temporal trend, 1996-2004, in Sweden
    Open this publication in new window or tab >>Exposure of perfluorinated chemicals through lactation: levels of matched human milk and serum and a temporal trend, 1996-2004, in Sweden
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    2007 (English)In: Environmental Health Perspectives, ISSN 0091-6765, Vol. 115, no 2, p. 226-230Article in journal (Refereed) Published
    Abstract [en]

    Background Only limited data exist on lactation as an exposure source of persistent perfluorinated chemicals (PFCs) for children.Objectives We studied occurrence and levels of PFCs in human milk in relation to maternal serum together with the temporal trend in milk levels between 1996 and 2004 in Sweden. Matched, individual human milk and serum samples from 12 primiparous women in Sweden were analyzed together with composite milk samples (25–90 women/year) from 1996 to 2004.Results Eight PFCs were detected in the serum samples, and five of them were also above the detection limits in the milk samples. Perfluorooctanesulfonate (PFOS) and perfluorohexanesulfonate (PFHxS) were detected in all milk samples at mean concentrations of 0.201 ng/mL and 0.085 ng/mL, respectively. Perfluorooctanesulfonamide (PFOSA), perfluorooctanoic acid (PFOA), and perfluorononanoic acid (PFNA) were detected less frequently.Discussion The total PFC concentration in maternal serum was 32 ng/mL, and the corresponding milk concentration was 0.34 ng/mL. The PFOS milk level was on average 1% of the corresponding serum level. There was a strong association between increasing serum concentration and increasing milk concentration for PFOS (r2 = 0.7) and PFHxS (r2 = 0.8). PFOS and PFHxS levels in composite milk samples were relatively unchanged between 1996 and 2004, with a total variation of 20 and 32% coefficient of variation, respectively.Conclusion The calculated total amount of PFCs transferred by lactation to a breast-fed infant in this study was approximately 200 ng/day. Lactation is a considerable source of exposure for infants, and reference concentrations for hazard assessments are needed.

    National Category
    Environmental Sciences Chemical Sciences
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-3120 (URN)10.1289/ehp.9491 (DOI)
    Available from: 2006-09-22 Created: 2006-09-22 Last updated: 2017-10-18Bibliographically approved
  • 185.
    Kärrman, Anna
    et al.
    Örebro University, Department of Natural Sciences.
    Ericson Jogsten, Ingrid
    Örebro University, Department of Natural Sciences.
    van Bavel, Bert
    Örebro University, Department of Natural Sciences.
    Darnerud, Per Ola
    Aune, Marie
    Glynn, Anders
    Lignell, Sanna
    Lindström, Gunilla
    Örebro University, Department of Natural Sciences.
    Exposure of perfluorinated chemicals through lactation: levels of matched human milk and serum and a temporal trend, 1996-2004, in Sweden2007In: Environmental Health Perspectives, ISSN 0091-6765, Vol. 115, no 2, p. 226-230Article in journal (Refereed)
    Abstract [en]

    Background Only limited data exist on lactation as an exposure source of persistent perfluorinated chemicals (PFCs) for children.Objectives We studied occurrence and levels of PFCs in human milk in relation to maternal serum together with the temporal trend in milk levels between 1996 and 2004 in Sweden. Matched, individual human milk and serum samples from 12 primiparous women in Sweden were analyzed together with composite milk samples (25–90 women/year) from 1996 to 2004.Results Eight PFCs were detected in the serum samples, and five of them were also above the detection limits in the milk samples. Perfluorooctanesulfonate (PFOS) and perfluorohexanesulfonate (PFHxS) were detected in all milk samples at mean concentrations of 0.201 ng/mL and 0.085 ng/mL, respectively. Perfluorooctanesulfonamide (PFOSA), perfluorooctanoic acid (PFOA), and perfluorononanoic acid (PFNA) were detected less frequently.Discussion The total PFC concentration in maternal serum was 32 ng/mL, and the corresponding milk concentration was 0.34 ng/mL. The PFOS milk level was on average 1% of the corresponding serum level. There was a strong association between increasing serum concentration and increasing milk concentration for PFOS (r2 = 0.7) and PFHxS (r2 = 0.8). PFOS and PFHxS levels in composite milk samples were relatively unchanged between 1996 and 2004, with a total variation of 20 and 32% coefficient of variation, respectively.Conclusion The calculated total amount of PFCs transferred by lactation to a breast-fed infant in this study was approximately 200 ng/day. Lactation is a considerable source of exposure for infants, and reference concentrations for hazard assessments are needed.

  • 186.
    Kärrman, Anna
    et al.
    Örebro University, Department of Natural Sciences.
    Langlois, Ingrid
    van Bavel, Bert
    Örebro University, Department of Natural Sciences.
    Lindström, Gunilla
    Örebro University, Department of Natural Sciences.
    Oehme, Michael
    Analysis of perfluorooctane sulfonate (PFOS) isomers: identification and pattern in human blood from Sweden, the United Kingdom and AustraliaManuscript (preprint) (Other academic)
  • 187.
    Kärrman, Anna
    et al.
    Örebro University, Department of Natural Sciences.
    Langlois, Ingrid
    van Bavel, Bert
    Örebro University, Department of Natural Sciences.
    Lindström, Gunilla
    Örebro University, Department of Natural Sciences.
    Oehme, Michael
    Identification and pattern of perfluorooctane sulfonate (PFOS) isomers in human serum and plasma2007In: Environment International, ISSN 0160-4120, E-ISSN 1873-6750, Vol. 33, no 6, p. 782-788Article in journal (Refereed)
    Abstract [en]

    Human serum and plasma from Sweden (n=17), the United Kingdom (the UK) (n=13) and Australia (n=40) were analyzed by high performance liquid chromatography coupled to mass spectrometry. The objective was to identify different perfluorooctane sulfonate (PFOS) isomers. Similar isomer patterns typical for the electrochemical fluorination (ECF) process were found for all samples. The linear PFOS (L-PFOS) was the major isomer found (58-70%) followed by the monosubstituted PFOS isomers 1/6-CF(3)-PFOS (18-22%) and 3/4/5-CF(3)-PFOS (13-18%). Disubstituted isomers were also detected. The percentage of L-PFOS found in the serum and plasma samples was lower compared to a standard PFOS product (76-79%). The pattern of PFOS isomers in human serum and plasma may be suggestive concerning potential isomeric discrimination since PFOS is only produced by ECF. Possibilities for such isomer discrimination are discussed. Significant higher content of L-PFOS (68%) in Swedish samples compared to Australia and the UK (59%) was also found, which may suggest differences in exposure sources for humans.

  • 188.
    Kärrman, Anna
    et al.
    Örebro University, Department of Natural Sciences.
    Mueller, Jochen F.
    van Bavel, Bert
    Örebro University, Department of Natural Sciences.
    Harden, Fiona
    Toms, Leisa-Maree L.
    Lindström, Gunilla
    Örebro University, Department of Natural Sciences.
    Levels of 12 perfluorinated chemicals in pooled Australian serum, collected 2002-2003, in relation to age, gender, and region2006In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 40, no 12, p. 3742-3748Article in journal (Refereed)
    Abstract [en]

    Pooled serum samples from 3802 Australian residents were analyzed for four perfluoroalkylsulfonates, seven perfluoroalkylcarboxylates, and perfluorooctanesulfonamide (PFOSA). Serum was collected from men and women of five different age groups and from rural and urban regions in Australia. The highest mean concentration was obtained for perfluorooctane sulfonate (PFOS, 20.8 ng/mL) followed by perfluorooctanoic acid (PFOA, 7.6 ng/mL), perfluorohexane sulfonate (PFHxS, 6.2 ng/mL), perfluorononanoic acid (PFNA, 1.1 ng/mL), and PFOSA (0.71 ng/mL). Additional four PFCs were detected in 5-18% of the samples at concentrations near the detection limits (0.1-0.5 ng/mL). An increase in PFOS concentration with increasing age in both regions and genders was observed. The male pool levels of some of the age groups compared to females were higherfor PFOS, PFOA, and PFHxS. In contrast, PFNA concentrations were higher in the female pools. No substantial difference was found in levels of PFCs between the urban and rural regions. The levels are equal or higher than previously reported serum levels in Europe and Asia but lower compared to the U.S.A. These results suggest that emissions from production in the Northern Hemisphere are of less importance for human exposure.

  • 189.
    Kärrman, Anna
    et al.
    Örebro University, Department of Natural Sciences.
    van Bavel, Bert
    Örebro University, Department of Natural Sciences.
    Järnberg, Ulf
    Hardell, Lennart
    Lindström, Gunilla
    Örebro University, Department of Natural Sciences.
    Development of a solid-phase extraction-HPLC/Single quadrupole MS method for quantification of perfluorochemicals in whole blood2005In: Analytical Chemistry, ISSN 0003-2700, E-ISSN 1520-6882, Vol. 77, no 3, p. 864-870Article in journal (Refereed)
    Abstract [en]

    A method for the determination of perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA) simultaneously with 10 closely related perfluorochemicals (PFCs) in human whole blood was developed and validated. PFOS and PFOA are used in various applications, for example, as surfactants and plastic additives, and are subject to environmental and health research due to their persistence. The main part of the data on PFCs in human blood is from serum samples, analyzed mainly by ion pair extraction followed by high-performance liquid chromatography (HPLC) and negative electrospray (ESI) tandem mass spectrometry (MS/MS). The analytical method developed here is suitable for human whole blood and involves solid-phase extraction (SPE) and HPLC negative electrospray single quadrupole mass spectrometry (HPLC/ES-MS). A whole blood aliquot was treated with formic acid and extracted on a octadecyl (C18) SPE column. The PFCs were isolated with methanol, and quantification was performed using single quadrupole mass spectrometry and perfluoroheptanoic acid as internal standard. Validation was performed in the range 0.3-194 ng/mL with recovery between 64 and 112% and limit of detection in the 0.1-0.5 ng/mL range for 11 of the 12 PFCs studied. We applied this method to 20 whole blood samples collected in 1997-2000 from the Swedish population in the ages 24-72. Eleven of the 12 PFCs were detected, and they were quantitatively and qualitatively confirmed using triple quadrupole LC/MS/MS analysis. PFOS, perfluorooctanesulfonamide, perfluorohexanesulfonate, PFOA and perfluorononanoic acid were quantified in all samples. In addition, perfluorohexanoic acid, perfluorodecanoic acid, perfluorodecanesulfonate, perfluoroundecanoic acid, perfluorododecanoic acid, and perfluorotetradecanoic acid were detected in some samples. This study shows that SPE and single quadrupole MS can be applied for extraction and quantification of PFCs in human whole blood, resulting in selectivity and low detection limits.

  • 190.
    Kärrman, Anna
    et al.
    Örebro University, Department of Natural Sciences.
    van Bavel, Bert
    Örebro University, Department of Natural Sciences.
    Järnberg, Ulf
    Hardell, Lennart
    Lindström, Gunilla
    Örebro University, Department of Natural Sciences.
    Perfluorinated chemicals in relation to other persistent organic pollutants in human blood2006In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 64, no 9, p. 1582-1591Article in journal (Refereed)
    Abstract [en]

    In order to evaluate blood levels of some perfluorinated chemicals (PFCs) and compare them to current levels of classical persistent organic pollutants (POPs) whole blood samples from Sweden were analyzed with respect to 12 PFCs, 37 polychlorinated biphenyls (PCBs), p,p'-dichlorodiphenyl-dichloroethylene (DDE), hexachlorobenzene (HCB), six chlordanes and three polybrominated diphenyl ethers (PBDEs). The median concentration, on whole blood basis, of the sum of PFCs was 20-50 times higher compared to the sum of PCBs and p,p'-DDE, 300-450 times higher than HCB, sum of chlordanes and sum of PBDEs. Estimations of the total body amount of PFCs and lipophilic POPs point at similar body burdens. While levels of for example PCBs and PBDEs are normalized to the lipid content of blood, there is no such general procedure for PFCs in blood. The distributions of a number of perfluorinated compounds between whole blood and plasma were therefore studied. Plasma concentrations were higher than whole blood concentrations for four perfluoroalkylated acids with plasma/whole blood ratios between 1.1 and 1.4, whereas the ratio for perflurooctanesulfonamide (PFOSA) was considerably lower (0.2). This suggests that the comparison of levels of PFCs determined in plasma with levels determined in whole blood should be made with caution. We also conclude that Swedish residents are exposed to a large number of PFCs to the same extent as in USA, Japan, Colombia and the few other countries from which data is available today.

  • 191. Labet, Vanessa
    et al.
    Grand, André
    Cadet, Jean
    Eriksson, Leif A.
    Örebro University, Department of Natural Sciences.
    Deamination of the radical cation of the base moiety of 2’deoxycytidine: A theoretical study2008In: ChemPhysChem, ISSN 1439-4235, E-ISSN 1439-7641, Vol. 9, no 8, p. 1195-1203Article in journal (Refereed)
    Abstract [en]

    Five pathways leading to the deamination of cytosine (to uracil) after formation of its deprotonated radical cation are investigated in the gas phase, at the UB3LYP/6-311GACHTUNGTRENUNG(d,p) level of theory, and in bulk aqueous solvent. The most favorable pathway involves hydrogen-atom transfer from a water molecule to the N3 nitrogen of the deprotonated radical cation, followed by addition of the resulting hydroxyl radical to the C4 carbon of the cytosine derivative. Following protonation of the amino group (N4), the C4 N4 bond is broken with elimination of the NH3 ·+ radical and formation of a protonated uracil. The rate-determining step of this mechanism is hydrogen-atom transfer from a water molecule to the cytosine derivative. The associated free energy barrier is 70.2 kJmol 1.

  • 192. Labet, Vanessa
    et al.
    Grand, André
    Morell, Christophe
    Cadet, Jean
    Eriksson, Leif A.
    Örebro University, Department of Natural Sciences.
    Proton catalyzed hydrolytic deamination of cytosine: a computational study2008In: Theoretical Chemistry accounts, ISSN 1432-881X, E-ISSN 1432-2234, Vol. 120, no 4-6, p. 429-435Article in journal (Refereed)
    Abstract [en]

    Two pathways involving proton catalyzed hydrolytic deamination of cytosine (to uracil) are investigated at the PCM-corrected B3LYP/6-311G(d,p) level of theory, in the presence of an additional catalyzing water molecule. It is concluded that the pathway involving initial protonation at nitrogen in position 3 of the ring, followed by water addition at C4 and proton transfer to the amino group, is a likely route to hydrolytic deamination. The rate determining step is the addition of water to the cytosine, with a calculated free energy barrier in aqueous solution of G==140 kJ/mol. The current mechanism provides a lower barrier to deamination than previous work based on OH− catalyzed reactions, and lies closer to the experimental barrier derived from rate constants (Ea = 117 ± 4kJ/mol).

  • 193. Lacayo Romero, Martha
    et al.
    Terrazas, Enrique
    van Bavel, Bert
    Örebro University, Department of Natural Sciences.
    Mattiasson, Bo
    Degradation of toxaphene by Bjerkandera sp. strain BOL13 using waste biomass as a cosubstrate2006In: Applied Microbiology and Biotechnology, ISSN 0175-7598, E-ISSN 1432-0614, Vol. 71, no 4, p. 549-554Article in journal (Refereed)
    Abstract [en]

    The white-rot fungus Bjerkandera sp. strain BOL13 was capable of degrading toxaphene when supplied with wood chips, wheat husk or cane molasses as cosubstrates in batch culture experiments. Approximately 85% of toxaphene was removed when wheat husk was the main substrate. The production of lignin peroxidase was only stimulated when wheat husk was present in the liquid medium. Although xylanase was always detected, wheat husk supported the highest xylanase production. A negligible amount of beta-glucosidase and cellulase were found in the batch culture medium. To the best of our knowledge, this is the first reported case of toxaphene degradation by white-rot fungi.

  • 194. Lacayo-Romero, Martha
    et al.
    Quillaguamán, Jorge
    van Bavel, Bert
    Örebro University, Department of Natural Sciences.
    Mattiasson, Bo
    A toxaphene-degrading bacterium related to Enterobacter cloacae, strain D1 isolated from aged contaminated soil in Nicaragua2005In: Systematic and Applied Microbiology, ISSN 0723-2020, E-ISSN 1618-0984, Vol. 28, no 7, p. 632-639Article in journal (Refereed)
    Abstract [en]

    Enterobacter sp. strain D1 is a facultative anaerobic, Gram-negative heterotrophic bacterium isolated from toxaphene-contaminated soil. This organism was identified and characterized through phylogenetic and taxonomic studies. Based on 16S rDNA analysis, the strain D1 was clustered closely with the species Enterobacter cloacae subsp. dissolvens (LMG 2683) and E. cloacae (ATCC 13047T). Strain D1 resembled these E. cloacae strains with respect to various biochemical and nutritional characteristics, but also exhibited differences. Moreover, strain D1 is able to grow and survive with toxaphene supplied in the medium in the range 3-96 mg/L. Amongst the chemical components of toxaphene, octachlorocamphenes, nonachlorobornanes and decachlorobornanes were seen to be rapidly metabolized, although levels of hexachlorocamphenes and heptachlorobornanes were found to be slowly degraded, and subsequently accumulated during the last stage of the cultivation.

  • 195. Lacayo-Romero, Martha
    et al.
    van Bavel, Bert
    Örebro University, Department of Natural Sciences.
    Mattiasson, Bo
    Degradation of toxaphene in aged and freshly contaminated soil2006In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 63, no 4, p. 609-615Article in journal (Refereed)
    Abstract [en]

    Degradation of toxaphene in soil from both newly contaminated (from Sweden) and aged spills (from Nicaragua) were studied. The newly contaminated soil contained approximately 11 mg kg(-1) toxaphene while the aged Nicaraguan soil contained approximately 100 mg kg(-1). Degradation was studied in anaerobic bioreactors, some of which were supplied with lactic acid and others with Triton X-114. In this study we found that the lower isomers Parlar 11, 12 were degraded while the concentration of isomer Parlar 15 increased. This supported an earlier evaluation which indicated that less chlorinated isomers are formed from more heavily isomers. Lactic acid when added to the soil, interfere with the degradation of toxaphene. Lactic acid was added; several isomers appeared to degrade rather slowly in newly contaminated Swedish soil. The Swedish soil, without any external carbon source, showed the slowest degradation rate of all the compounds studied. When Triton X-114 at 0.4 mM was added, the degradation rate of the compounds increased. This study illustrates that biodegradation of toxaphene is a complex process and several parameters have to be taken into consideration. Degradation of persistent pollutants in the environment using biotechnology is dependent on bioavailability, carbon sources and formation of metabolites.

  • 196.
    Larsson, Anders
    et al.
    Örebro University, Department of Natural Sciences.
    Eriksson, Leif A.
    Örebro University, Department of Natural Sciences.
    Andersson, Patrik L.
    Ivarson, Per
    Olsson, Per-Erik
    Örebro University, Department of Natural Sciences.
    Identification of the brominated flame retardant 1,2-dibromo-4-(1,2-dibromoethyl)cyclohexane as an androgen agonist2006In: Journal of medicinal chemistry, ISSN 0022-2623, Vol. 49, no 25, p. 7366-7372Article in journal (Refereed)
    Abstract [en]

    To investigate androgen receptor (AR) activation by exogenous compounds, we used a combination of experimental analysis and theoretical modeling to compare a set of brominated flame retardants (BFRs) to dihydrotestosterone (DHT) with regard to ligand docking, AR binding, and AR activation in human hepatocellular liver carcinoma cells, as well as interacting energy analysis. Modeling of receptor docking was found to be a useful first step in predicting the potential to translocate to the ligand pocket of the receptor, and the computed interaction energy was found to correlate with the observed binding affinity. Flexible alignment studies of the BFR compounds demonstrated that 1,2-dibromo-4-(1,2-dibromoethyl)cyclohexane (BCH) closely overlap DHT. Combining the theoretical modeling with in vitro ligand-binding and receptor-activation assays, we show that BCH binds to and activates the human AR. The remaining BFRs did not successfully interact with the ligand pocket, were not able to replace a synthetic androgen from the receptor, and failed to activate the receptor.

  • 197.
    Li, Shaoshan
    et al.
    Örebro University, Department of Natural Sciences.
    Strid, Åke
    Örebro University, Department of Natural Sciences.
    Anthocyanin accumulation and changes in CHS and PR-5 gene expression in Arabidopsis thaliana after removal of the inflorescence stem (decapitation)2005In: Plant physiology and biochemistry (Paris), ISSN 0981-9428, E-ISSN 1873-2690, Vol. 43, no 6, p. 521-525Article in journal (Refereed)
    Abstract [en]

    Anthocyanin accumulation occurs in rosette leaves of Arabidopsis thaliana within 8 days after removal of the inflorescence stem. Expression of stress-induced genes CHS and PR-5 was strongly up-regulated by stem removal, and was highest on day 4 after decapitation. These levels were 10 and 5 times higher than in the control, respectively. No obvious difference was found in expression of LHCB, MEB5.2, or PYROA genes following stem removal. We demonstrate that removing the inflorescence stem triggers events in Arabidopsis, including pigment accumulation and changes in gene expression of a subset of stress-induced genes, in a tissue distant from the wound site.

  • 198.
    Lifvergren, Thomas
    Örebro University, Department of Natural Sciences.
    Remediation of mercury polluted soil2001Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Mercury in contaminated soil constitutes a wide spectrum of species with highly different properties due to the chemical complexity of the element. Assessments of risk, ecological effects and removal potential require process and mobility studies. Identification of various chemical states of mercury in soil systems can be achieved by selective extraction procedures that would demonstrate the mobility and potential reactivity. In this thesis, a selective extraction method for mercury is presented. The method is mainly based on a parallel extraction procedure. The method was used to investigate the mercury mobility in two soils collected at two different chlor-alkali industrial sites; Bohus and Bengtfors. Both soils are heavily contaminated with mercury, 80 and 180 mg Hg/kg, respectively. In Bohus soil mercury was associated to organic matter with low water solubility and to a very resistant phase, strongly indicated to be dominated by mercury sulphides. In Bengtfors soil some mercury appeared to be weakly adsorbed, bound to secondary precipitates and associated to soluble humic matter. These result indicates a higher mobility of mercury in Bengtfors compared to Bohus soil. Both soils are fine grained with a clay dominated matrix. The main difference is the sulphur content. 0.4% and 0.03% for Bohus and Bengtfors soil, respectively. The preference of mercury for sulphides and reduced sulphur groups in organic matter is well established. The corresponding phases are in general very insoluble. This indicates that sulphur contents in soil to some extent reflects geochemical speciation as well as mobility of mercury.

    Further, the possibility to mobilise insoluble mercury phases in soils using soil fungi as well as halogenides were investigated. This was made in an attempt to investigate possible in-situ technologies for remediation of mercury polluted soils. Some of the fungi studied were able to dissolve mercury sulphides. It was also indicated that the same fungi responded with volatilsation, accumulation and possible also precipitation of mercury, as soon as toxic levels of soluble mercury were reached. These latter responses can be of advantage or disadvantage depending on remediation design.

    In batch experiments made with acidic iodide solutions and Bohus soil, a very fast and extensively dissolution of mercury was shown. Mobilisation of the mercury sulphide fraction present, could not be achieved solely by competitive complexation. The mechanism suggested was formation of tri-iodide at low pH. The combination of complextion and oxidation in the same molecule, breaks the bond between inorganic mercury and the sulphide. Extensively and fast mobilisation was also seen in a bench experiment, where iodide in combination with electroremediation simulated a possible in-situ remediation of Bohus soil.

    List of papers
    1. Microwave-assisted digestion of mercury polluted soils
    Open this publication in new window or tab >>Microwave-assisted digestion of mercury polluted soils
    (English)Manuscript (preprint) (Other academic)
    National Category
    Natural Sciences
    Research subject
    Enviromental Science
    Identifiers
    urn:nbn:se:oru:diva-16010 (URN)
    Available from: 2011-06-17 Created: 2011-06-17 Last updated: 2017-10-17Bibliographically approved
    2. Remediation of mercury polluted soils - I: selective extraction of mercury from a soil and speciation by gas chromatography - atomic emission detection
    Open this publication in new window or tab >>Remediation of mercury polluted soils - I: selective extraction of mercury from a soil and speciation by gas chromatography - atomic emission detection
    (English)Manuscript (preprint) (Other academic)
    National Category
    Natural Sciences
    Research subject
    Enviromental Science
    Identifiers
    urn:nbn:se:oru:diva-16011 (URN)
    Available from: 2011-06-17 Created: 2011-06-17 Last updated: 2017-10-17Bibliographically approved
    3. Mercury speciation and mobility in two contaminated soils
    Open this publication in new window or tab >>Mercury speciation and mobility in two contaminated soils
    (English)Manuscript (preprint) (Other academic)
    National Category
    Natural Sciences
    Research subject
    Enviromental Science
    Identifiers
    urn:nbn:se:oru:diva-16013 (URN)
    Available from: 2011-06-17 Created: 2011-06-17 Last updated: 2017-10-17Bibliographically approved
    4. Critical remarks concerning the method used in Sweden for risk assessment of contaminated soils (MIFO)
    Open this publication in new window or tab >>Critical remarks concerning the method used in Sweden for risk assessment of contaminated soils (MIFO)
    (English)Manuscript (preprint) (Other academic)
    National Category
    Chemical Sciences
    Research subject
    Enviromental Science
    Identifiers
    urn:nbn:se:oru:diva-16009 (URN)
    Available from: 2011-06-17 Created: 2011-06-17 Last updated: 2017-10-17Bibliographically approved
    5. Fungal responses to mercury
    Open this publication in new window or tab >>Fungal responses to mercury
    Show others...
    (English)Manuscript (preprint) (Other academic)
    National Category
    Natural Sciences
    Research subject
    Enviromental Science
    Identifiers
    urn:nbn:se:oru:diva-16014 (URN)
    Available from: 2011-06-17 Created: 2011-06-17 Last updated: 2017-10-17Bibliographically approved
    6. Remediation of mercury polluted soils - part II: mobilisation of mercury in soil by complexation with chloride and iodide
    Open this publication in new window or tab >>Remediation of mercury polluted soils - part II: mobilisation of mercury in soil by complexation with chloride and iodide
    (English)Manuscript (preprint) (Other academic)
    National Category
    Natural Sciences
    Research subject
    Enviromental Science
    Identifiers
    urn:nbn:se:oru:diva-16015 (URN)
    Available from: 2011-06-17 Created: 2011-06-17 Last updated: 2017-10-17Bibliographically approved
    7. Mercury contaminated soil: remediation by the combination of iodide and electroreclamation
    Open this publication in new window or tab >>Mercury contaminated soil: remediation by the combination of iodide and electroreclamation
    (English)Manuscript (preprint) (Other academic)
    National Category
    Natural Sciences
    Research subject
    Enviromental Science
    Identifiers
    urn:nbn:se:oru:diva-16016 (URN)
    Available from: 2011-06-17 Created: 2011-06-17 Last updated: 2017-10-17Bibliographically approved
  • 199.
    Lifvergren, Thomas
    et al.
    Örebro University, Department of Natural Sciences.
    Alvelöv, F.
    Allard, Bert
    Örebro University, Department of Natural Sciences.
    Mercury speciation and mobility in two contaminated soilsManuscript (preprint) (Other academic)
  • 200.
    Lifvergren, Thomas
    et al.
    Örebro University, Department of Natural Sciences.
    Krantz-Rülcker, Christina
    Ledin, Maria
    Persson, Charlotta
    Karlsson, Stefan
    Örebro University, Department of Natural Sciences.
    Allard, Bert
    Örebro University, Department of Natural Sciences.
    Gadd, Geoffrey M.
    Fungal responses to mercuryManuscript (preprint) (Other academic)
1234567 151 - 200 of 350
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