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  • 1.
    Aarseth Larsson, Kim
    Örebro University, School of Science and Technology.
    Chemical Characterisation of Nitrocellulose2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Nitrocellulose is the main component in many types of ammunition, propellants and explosives. The principles of production for nitrocellulose have not changed much since the 19th century when it started being industrially produced for this purpose. The character of the nitrocellulose has a large effect on the end products abilities. The aim of this study was to develop a method that would be able to characterise and distinguish between nitrocellulose from different manufacturers to be able to relate the character of the nitrocellulose to the properties of ammunition, propellants and explosives. Samples were dissolved in acetone and analysed by GC/MS and data were then analysed by multivariable statistics. FTIR was also used to characterise the nitrocellulose. Results from both methods showed very small differences when chromatograms and spectra were analysed. This study shows that GC/MS and FTIR are not suitable for this type of characterisation. The differences between the data were not sufficient to be able to separate the samples from each other.

  • 2.
    Abalos, M.
    et al.
    MTM Research Center, Örebro University, Örebro, Sweden.
    Abad, E.
    Laboratory of Dioxins, Mass Spectrometry Laboratory, Environmental Chemistry Dept., IDÆA-CSIC, Barcelona, Spain.
    van Leeuwen, S. P. J.
    Institute for Environmental Studies (IVM), Vrije University, Amsterdam, Netherlands; RIKILT-Institute of Food Safety, Wageningen, Netherlands.
    Lindström, Gunilla
    Örebro University, School of Science and Technology.
    Fiedler, Heidelore
    UNEP Chemicals, Châtelaine GE, Switzerland.
    de Boer, J.
    Institute for Environmental Studies (IVM), Vrije University, Amsterdam, Netherlands.
    van Bavel, Bert
    Results for PCDD/PCDF and dl-PCBs in the first round of UNEPs biennial global interlaboratory assessment on persistent organic pollutants2013In: TrAC. Trends in analytical chemistry, ISSN 0165-9936, E-ISSN 1879-3142, Vol. 46, p. 98-109Article in journal (Refereed)
    Abstract [en]

    The first worldwide interlaboratory assesment on persistent organic pollutants (POPs) under the Stockholm Convention was organized in the Asian/Pacific, Latin American and African regions during 2009-11.

    A relatively large number of laboratories reported data for the PCDDs/PCDFs and dioxin-like PCBs, especially in the Asian region. Within the Asian region, several participants used high-resolution GC/high-resolution MS systems optimized for dioxin analysis. The availibility of High-resolution mass spectrometer instrumentation is limited in the Latin America and African regions, although recently several new laboratories for dioxins have started in the Latin American region.

  • 3.
    Abrikossova, Natalia
    et al.
    Division of Molecular Surface Physics and Nanoscience, Department of Physics, Chemistry and Biology, Linköping University, Linköping, Sweden .
    Skoglund, Caroline
    Division of Molecular Surface Physics and Nanoscience, Department of Physics, Chemistry and Biology, Linköping University, Linköping, Sweden; Division of Clinical Medicine, Department of Biomedicine, Örebro University, Örebro, Sweden.
    Ahrén, Maria
    Division of Molecular Surface Physics and Nanoscience, Department of Physics, Chemistry and Biology, Linköping University, Linköping, Sweden.
    Bengtsson, Torbjörn
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Division of Clinical Medicine, Department of Biomedicine, School of Health and Medical Sciences, Örebro University, Örebro, Sweden.
    Uvdal, Kajsa
    Division of Molecular Surface Physics and Nanoscience, Department of Physics, Chemistry and Biology, Linköping University, Linköping, Sweden.
    Effects of gadolinium oxide nanoparticles on the oxidative burst from human neutrophil granulocytes2012In: Nanotechnology, ISSN 0957-4484, E-ISSN 1361-6528, Vol. 23, no 27, article id 275101Article in journal (Refereed)
    Abstract [en]

    We have previously shown that gadolinium oxide (Gd2O3) nanoparticles are promising candidates to be used as contrast agents in magnetic resonance (MR) imaging applications. In this study, these nanoparticles were investigated in a cellular system, as possible probes for visualization and targeting intended for bioimaging applications. We evaluated the impact of the presence of Gd2O3 nanoparticles on the production of reactive oxygen species (ROS) from human neutrophils, by means of luminol-dependent chemiluminescence. Three sets of Gd2O3 nanoparticles were studied, i.e. as synthesized, dialyzed and both PEG-functionalized and dialyzed Gd2O3 nanoparticles. In addition, neutrophil morphology was evaluated by fluorescent staining of the actin cytoskeleton and fluorescence microscopy. We show that surface modification of these nanoparticles with polyethylene glycol (PEG) is essential in order to increase their biocompatibility. We observed that the as synthesized nanoparticles markedly decreased the ROS production from neutrophils challenged with prey (opsonized yeast particles) compared to controls without nanoparticles. After functionalization and dialysis, more moderate inhibitory effects were observed at a corresponding concentration of gadolinium. At lower gadolinium concentration the response was similar to that of the control cells. We suggest that the diethylene glycol (DEG) present in the as synthesized nanoparticle preparation is responsible for the inhibitory effects on the neutrophil oxidative burst. Indeed, in the present study we also show that even a low concentration of DEG, 0.3%, severely inhibits neutrophil function. In summary, the low cellular response upon PEG-functionalized Gd2O3 nanoparticle exposure indicates that these nanoparticles are promising candidates for MR-imaging purposes.

  • 4.
    Adamovic, Tatjana
    et al.
    Dept Mol Med & Surg, Karolinska Inst, Stockholm, Sweden.
    McAllister, Donna
    Dept Surg, Med Coll Wisconsin, Milwaukee WI, USA.
    Wang, Tao
    Dept Biostat, Dept Populat Hlth, Med Coll Wisconsin, Milwaukee WI, USA.
    Adamovic, Dragan
    Örebro University, School of Science and Technology.
    Rowe, J. Jordi
    Dept Anat Pathol, Cleveland Clin, Cleveland OH, USA.
    Moreno, Carol
    Dept Physiol, Med Coll Wisconsin, Milwaukee WI, USA; Human & Mol Genet Ctr, Med Coll Wisconsin, Milwaukee WI, USA.
    Lazar, Josef
    Human & Mol Genet Ctr, Med Coll Wisconsin, Milwaukee WI, USA; Dept Dermatol, Med Coll Wisconsin, Milwaukee WI, USA.
    Jacob, Howard J.
    Dept Physiol, Med Coll Wisconsin, Milwaukee WI, USA; Med Coll Wisconsin, Human & Mol Genet Ctr, Milwaukee WI, USA; Dept Pediat, Med Coll Wisconsin, Milwaukee WI, USA.
    Sugg, Sonia L.
    Dept Surg, Univ Iowa, Iowa City IA, USA.
    Identification of novel carcinogen-mediated mammary tumor susceptibility loci in the rat using the chromosome substitution technique2010In: Genes, Chromosomes and Cancer, ISSN 1045-2257, E-ISSN 1098-2264, Vol. 49, no 11, p. 1035-1045Article in journal (Refereed)
    Abstract [en]

    We here report the genetic basis for susceptibility and resistance to carcinogen-mediated [7,12-dimethylbenz[a] anthracene (DMBA)] mammary tumorigenesis using the full panel of SS/BN consomic rat strains, in which substitutions of individual chromosomes from the resistant BN strain onto the genomic background of the susceptible SS strain were made. Analysis of 252 consomic females identified rat mammary Quantitative Trait Loci (QTLs) affecting tumor incidence on chromosomes 3 and 5, latency on chromosomes 3, 9, 14, and 19, and multiplicity on chromosomes 13, 16, and 19. In addition, we unexpectedly identified a novel QTL on chromosome 6 controlling a lethal toxic phenotype in response to DMBA. Upon further investigation with chromosomes 6 and 13 congenic lines, in which an additional 114 rats were investigated, we mapped (1) a novel mammary tumor QTL to a region of 27.1 Mbp in the distal part of RNO6, a region that is entirely separated from the toxicity phenotype, and (2) a novel and powerful mammary tumor susceptibility locus of 4.5 Mbp that mapped to the proximal q-arm of RNO13. Comparison of genetic strain differences using existing rat genome databases enabled us to further construct priority lists containing single breast cancer candidate genes within the defined QTLs, serving as potential functional variants for future testing.

  • 5.
    Aghanavesi, Somayeh
    et al.
    School of Technology and Business Studies, Computer Engineering, Dalarna University, Falun, Sweden.
    Memedi, Mevludin
    Örebro University, Örebro University School of Business.
    Dougherty, Mark
    School of Technology and Business Studies, Computer Engineering, Dalarna University, Falun, Sweden.
    Nyholm, Dag
    Department of Neuroscience, Neurology, Uppsala University, Sweden.
    Westin, Jerker
    School of Technology and Business Studies, Computer Engineering, Dalarna University, Falun, Sweden.
    Verification of a Method for Measuring Parkinson’s Disease Related Temporal Irregularity in Spiral Drawings2017In: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 17, no 10, article id 2341Article in journal (Refereed)
    Abstract [en]

    Parkinson’s disease (PD) is a progressive movement disorder caused by the death of dopamine-producing cells in the midbrain. There is a need for frequent symptom assessment, since the treatment needs to be individualized as the disease progresses. The aim of this paper was to verify and further investigate the clinimetric properties of an entropy-based method for measuring PD-related upper limb temporal irregularities during spiral drawing tasks. More specifically, properties of a temporal irregularity score (TIS) for patients at different stages of PD, and medication time points were investigated. Nineteen PD patients and 22 healthy controls performed repeated spiral drawing tasks on a smartphone. Patients performed the tests before a single levodopa dose and at specific time intervals after the dose was given. Three movement disorder specialists rated videos of the patients based on the unified PD rating scale (UPDRS) and the Dyskinesia scale. Differences in mean TIS between the groups of patients and healthy subjects were assessed. Test-retest reliability of the TIS was measured. The ability of TIS to detect changes from baseline (before medication) to later time points was investigated. Correlations between TIS and clinical rating scores were assessed. The mean TIS was significantly different between healthy subjects and patients in advanced groups (p-value = 0.02). Test-retest reliability of TIS was good with Intra-class Correlation Coefficient of 0.81. When assessing changes in relation to treatment, TIS contained some information to capture changes from Off to On and wearing off effects. However, the correlations between TIS and clinical scores (UPDRS and Dyskinesia) were weak. TIS was able to differentiate spiral drawings drawn by patients in an advanced stage from those drawn by healthy subjects, and TIS had good test-retest reliability. TIS was somewhat responsive to single-dose levodopa treatment. Since TIS is an upper limb high-frequency-based measure, it cannot be detected during clinical assessment.

  • 6.
    Aissaoui, Nesrine
    et al.
    Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Gothenburg, Sweden.
    Moth-Poulsen, Kasper
    Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Gothenburg, Sweden.
    Käll, Mikael
    Department of Applied Physics, Chalmers University of Technology, Gothenburg, Sweden.
    Johansson, Peter
    Örebro University, School of Science and Technology.
    Wilhelmsson, L. Marcus
    Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Gothenburg, Sweden.
    Albinsson, Bo
    Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Gothenburg, Sweden.
    FRET enhancement close to gold nanoparticles positioned in DNA origami constructs2017In: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, Vol. 9, no 2, p. 673-683Article in journal (Refereed)
    Abstract [en]

    Here we investigate the energy transfer rates of a Förster resonance energy transfer (FRET) pair positioned in close proximity to a 5 nm gold nanoparticle (AuNP) on a DNA origami construct. We study the distance dependence of the FRET rate by varying the location of the donor molecule, D, relative to the AuNP while maintaining a fixed location of the acceptor molecule, A. The presence of the AuNP induces an alteration in the spontaneous emission of the donor (including radiative and non-radiative rates) which is strongly dependent on the distance between the donor and AuNP surface. Simultaneously, the energy transfer rates are enhanced at shorter D-A (and D-AuNP) distances. Overall, in addition to the direct influence of the acceptor and AuNP on the donor decay there is also a significant increase in decay rate not explained by the sum of the two interactions. This leads to enhanced energy transfer between donor and acceptor in the presence of a 5 nm AuNP. We also demonstrate that the transfer rate in the three "particle" geometry (D + A + AuNP) depends approximately linearly on the transfer rate in the donor-AuNP system, suggesting the possibility to control FRET process with electric field induced by 5 nm AuNPs close to the donor fluorophore. It is concluded that DNA origami is a very versatile platform for studying interactions between molecules and plasmonic nanoparticles in general and FRET enhancement in particular.

  • 7.
    Allard, Bert
    et al.
    Örebro University, School of Science and Technology.
    Bäckström, Mattias
    Örebro University, School of Science and Technology.
    Häller, Sara
    Örebro University, School of Science and Technology.
    Panova, Elena
    St Petersburgs universitet, St Petersburg, Ryssland.
    Grawunder, Anja
    Friedrich Sciller Univ., Jena, Germany.
    Karlsson, Stefan
    Örebro University, School of Science and Technology.
    Water chemistry and trace metal concentrations in an acidic alum shale pit lake: effects of liming2011In: Mine water: managing the challenges: proceedings of the International Mine Water Association Congress 2011 / [ed] Trude R.Rüde, Antje Freund, Christian Wolkersdorfer, Aachen: RWTH , 2011, p. 503-508Conference paper (Refereed)
  • 8.
    Allard, Bert
    et al.
    Örebro University, Department of Natural Sciences.
    Karlsson, Stefan
    Greis, Christina
    Örebro University, Department of Natural Sciences.
    Pettersson, Håkan
    Düker, Anders
    Redistribution pf Pu, Am, Cs and Np in salt marsh sediment - Wigtown Merse, Irish SeaManuscript (Other academic)
  • 9.
    Alnehem, Isabell
    Örebro University, School of Science and Technology.
    Assessment on Groundwater Contamination from a Former Hard Chromium Plating Site in Iggesund2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Before the persistent and toxicological properties of perfluoroalkyl and polyfluoroalkyl substances (PFASs) were known they were used worldwide. The thermal and chemical stability from the carbon-fluorine bond makes these substances desirable for industrial applications. One particular PFAS that have received much attention is perfluorooctanesulfonic acid (PFOS) which is included in the Stockholm convention. Analyses have detected PFASs, especially the ones with longer carbon chain, in the environment, wildlife and humans so replacements are being searched for. This study investigates groundwater around a former hard chromium plating site, which is one of the registered exceptions where PFOS still is used. Five different located sampling points were collected and analyzed from this site in Iggesund, which is in the northern parts of Sweden. The substances analyzed for were thirteen perfluorinated carboxylic acids (PFCAs: C4-C14, C16 and C18), five perfluorinated sulfonic acids (PFSAs: C4, C6, C8 and C10) and 6:2 fluorotelomer sulfonate (6:2 FTS). The 6:2 telomer substances is being used as a replacement for similar compounds with longer carbon chains, but are believed to undergo biotransformation to persistent alkyl acids like perfluorohexanoic acid (PFHxA) in the environment. Solid phase extraction was performed on 500 mL filtered groundwater with and the concentrated samples were analyzed on an Ultra Performance Liquid Chromatography (UPLC), tandem mass spectrometer. The glass microfiber filters used for filtrating the groundwater were analyzed for particle bound PFASs. Results from the water extraction analysis showed eight detected PFAS, with PFOS as the major contributor (72 - 9600 ng/L). The PFOS concentrations differs substantially between the five groundwater samples where the two sampling points located south of the facility, and closest to the actual hard chromium plating, were clearly higher than the other three. Two other substances detected in high concentration were perfluorobutanesulfonic acid (PFBuS), 8-1550 ng/L, and perfluorohexanesulfonic acid (PFHxS), 18-140 ng/L which can be produced as an impurity during the production of PFOS. PFCAs in all samples were detected in lower concentrations (1-25 ng/L).

    Additional to the PFAS analysis, the groundwater was also measured for chromium since the carcinogenic hexavalent form is used in the chromic acid bath during hard chromium plating. In the same two samples that had the highest PFAS concentration, chromium was found in high concentration, 34900-44800 μg/L. These result indicates that the chromic acid baths is the source for the elevated concentrations found in the groundwater. If the facilities are left to deteriorate it will lead to continuously spreading of chromium and the highly water soluble PFASs downstream to Iggesundså which is of concern for the environment and water living organisms.

  • 10.
    Amadei, Damien
    et al.
    Lab Chim & Biol Membranes & Nanoobjets (CBMN), UMR 5248, Univ Bordeaux, Pessac, France.
    Chatzidaki, Maria D.
    Örebro University, School of Science and Technology. Inst Theoret & Phys Chem, Inst Biol Med Chem & Biotechnol, Natl Hellen Res Fdn, Athens, Greece.
    Devienne, Julia
    Lab Chim & Biol Membranes & Nanoobjets (CBMN), UMR 5248, Univ Bordeaux, Pessac, France.
    Monteil, Julien
    Lab Chim & Biol Membranes & Nanoobjets (CBMN), UMR 5248, Univ Bordeaux, Pessac, France.
    Cansell, Maud
    Lab Chim & Biol Membranes & Nanoobjets (CBMN), UMR 5248, Univ Bordeaux, Pessac, France.
    Xenakis, Aristotelis
    Inst Theoret & Phys Chem, Inst Biol Med Chem & Biotechnol, Natl Hellen Res Fdn, Athens, Greece.
    Leal-Calderon, Fernando
    Lab Chim & Biol Membranes & Nanoobjets (CBMN), UMR 5248, Univ Bordeaux, Pessac, France.
    Low shear-rate process to obtain transparent W/O fine emulsions as functional foods2014In: Food Research International, ISSN 0963-9969, E-ISSN 1873-7145, Vol. 62, p. 533-540Article in journal (Refereed)
    Abstract [en]

    Edible transparent emulsions of the water-in-oil (W/O) type are highly sought after and currently not available. In such materials, the water droplets can be advantageously used as reservoirs to encapsulate biologically active hydrophilic substances (minerals, antioxidants, etc.). The emulsions must remain transparent, fluid and kinetically stable to meet consumers' requirements. In this paper, we describe a simple yet versatile process to fabricate food grade transparent W/O emulsions. Our method involves the preparation of coarse emulsions which are submitted to shear under laminar flow conditions to reduce their average droplet size. The process generates negligible heat and consequently, it preserves the integrity of thermally sensitive compounds. The obtained emulsions contain between 5 and 10 wt.% of aqueous droplets whose average droplet size is lower than 200 nm. They are kinetically stable for at least 2 months. Transparency results from the relatively low droplet size and the incorporation in the aqueous phase of hydrophilic solutes that decrease the refractive index mismatch between the two immiscible phases.

  • 11.
    Andersson, Erika
    et al.
    Örebro University, School of Science and Technology.
    Rotander, Anna
    Örebro University, School of Science and Technology.
    von Kronhelm, Thomas
    SAKAB.
    Berggren, Anna
    Analycen AB.
    Ivarsson, Per
    Analycen AB.
    Hollert, Henner
    RWTH Aachen university.
    Engwall, Magnus
    Örebro University, School of Science and Technology.
    AhR agonist and genotoxicant bioavailability in a PAH-contaminated soil undergoing biological treatment2009In: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 16, no 5, p. 521-530Article in journal (Refereed)
    Abstract [en]

    Degradation of the 16 US EPA priority PAHs in soil subjected to bioremediation is often achieved. However, the PAH loss is not always followed by a reduction in soil toxicity. For instance, bioanalytical testing of such soil using the chemical-activated luciferase gene expression (CALUX) assay, measuring the combined effect of all Ah receptor (AhR) activating compounds, occasionally indicates that the loss of PAHs does not correlate with the loss of Ah receptor-active compounds in the soil. In addition, standard PAH analysis does not address the issue of total toxicant bioavailability in bioremediated soil.

    To address these questions, we have used the CALUX AhR agonist bioassay and the Comet genotoxicity bioassay with RTL-W1 cells to evaluate the toxic potential of different extracts from a PAH-contaminated soil undergoing large-scale bioremediation. The extracts were also chemically analyzed for PAH16 and PCDD/PCDF. Soil sampled on five occasions between day 0 and day 274 of biological treatment was shaken with n-butanol with vortex mixing at room temperature to determine the bioavailable fraction of contaminants. To establish total concentrations, parts of the same samples were extracted using an accelerated solvent extractor (ASE) with toluene at 100A degrees C. The extracts were tested as inducers of AhR-dependent luciferase activity in the CALUX assay and for DNA breakage potential in the Comet bioassay.

    The chemical analysis of the toluene extracts indicated slow degradation rates and the CALUX assay indicated high levels of AhR agonists in the same extracts. Compared to day 0, the bioavailable fractions showed no decrease in AhR agonist activity during the treatment but rather an up-going trend, which was supported by increasing levels of PAHs and an increased effect in the Comet bioassay after 274 days. The bio-TEQs calculated using the CALUX assay were higher than the TEQs calculated from chemical analysis in both extracts, indicating that there are additional toxic PAHs in both extracts that are not included in the chemically derived TEQ.

    The response in the CALUX and the Comet bioassays as well as the chemical analysis indicate that the soil might be more toxic to organisms living in soil after 274 days of treatment than in the untreated soil, due to the release of previously sorbed PAHs and possibly also metabolic formation of novel toxicants.

    Our results put focus on the issue of slow degradation rates and bioavailability of PAHs during large-scale bioremediation treatments. The release of sorbed PAHs at the investigated PAH-contaminated site seemed to be faster than the degradation rate, which demonstrates the importance of considering the bioavailable fraction of contaminants during a bioremediation process.

    It has to be ensured that soft remediation methods like biodegradation or the natural remediation approach do not result in the mobilization of toxic compounds including more mobile degradation products. For PAH-contaminated sites this cannot be assured merely by monitoring the 16 target PAHs. The combined use of a battery of biotests for different types of PAH effects such as the CALUX and the Comet assay together with bioavailability extraction methods may be a useful screening tool of bioremediation processes of PAH-contaminated soil and contribute to a more accurate risk assessment. If the bioremediation causes a release of bound PAHs that are left undegraded in an easily extracted fraction, the soil may be more toxic to organisms living in the soil as a result of the treatment. A prolonged treatment time may be one way to reduce the risk of remaining mobile PAHs. In critical cases, the remediation concept might have to be changed to ex situ remediation methods.

  • 12.
    Andrén, Daniel
    et al.
    Department of Physics, Chalmers University of Technology, Göteborg, Sweden.
    Shao, Lei
    Department of Physics, Chalmers University of Technology, Göteborg, Sweden.
    Länk, Nils Odebo
    Department of Physics, Chalmers University of Technology, Göteborg, Sweden.
    Acimovic, Srdjan S.
    Department of Physics, Chalmers University of Technology, Göteborg, Sweden.
    Johansson, Peter
    Örebro University, School of Science and Technology. Department of Physics, Chalmers University of Technology, Göteborg, Sweden.
    Käll, Mikael
    Department of Physics, Chalmers University of Technology, Göteborg, Sweden.
    Probing Photothermal Effects on Optically Trapped Gold Nanorods by Simultaneous Plasmon Spectroscopy and Brownian Dynamics Analysis2017In: ACS Nano, ISSN 1936-0851, E-ISSN 1936-086X, Vol. 11, no 10, p. 10053-10061Article in journal (Refereed)
    Abstract [en]

    Plasmonic gold nanorods are prime candidates for a variety of biomedical, spectroscopy, data storage, and sensing applications. It was recently shown that gold nanorods optically trapped by a focused circularly polarized laser beam can function as extremely efficient nanoscopic rotary motors. The system holds promise for-applications ranging from nanofluidic flow control and nanorobotics to biomolecular actuation and analysis. However, to fully exploit this potential, one needs to be able to control and understand heating effects associated with laser trapping. We investigated photothermal heating of individual rotating gold nanorods by simultaneously probing their localized surface plasmon resonance spectrum and rotational Brownian dynamics over extended periods of time. The data reveal an extremely slow nanoparticle reshaping process, involving migration of the order of a few hundred atoms per minute, for moderate laser powers and a trapping wavelength close to plasmon resonance. The plasmon spectroscopy and Brownian analysis allows for separate temperature estimates based on the refractive index and the viscosity of the water surrounding a trapped nanorod. We show that both measurements yield similar effective temperatures, which correspond to the actual temperature at a distance of the order 10-15 nm from the particle surface. Our results shed light on photothermal processes on the nanoscale and will be useful in evaluating the applicability and performance of nanorod motors and optically heated nanoparticles for a variety of applications.

  • 13.
    Arwidsson, Zandra
    et al.
    Örebro University, School of Science and Technology. SAKAB AB, Kumla, Sweden.
    Allard, Bert
    Örebro University, School of Science and Technology.
    Remediation of Metal-Contaminated Soil by Organic Metabolites from Fungi II-Metal Redistribution2010In: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 207, no 1-4, p. 5-18Article in journal (Refereed)
    Abstract [en]

    Exudation of low molecular weight organic acids by fungi was studied in a project focusing on bioremediation of metal-contaminated soils. The production of acids (mainly oxalic and citric acid) as a response to nutrient variations and presence of metals has recently been reported (Arwidsson et al. 2009). A significant release of metals was observed and was related not only to the production of organic acids but also to the resulting pH decrease in the systems. The processes governing the release and redistribution of metals in the soil-water fungus system were the focus of the present continuation of the project, based on observations of Aspergillus niger, Penicillium bilaiae, and a Penicillium sp. The release of lead was 12% from the soil with the second highest initial load (1,600 mg kg(-1)), while the release of copper was 90% from the same soil (140 mg kg(-1)). The dominating mechanism behind the release and subsequent redistribution was the change in pH, going from near neutral to values in the range 2.1-5.9, reflecting the production of organic acids. For some of the systems, the formation of soluble complexes is indicated (copper, at intermediate pH) which favors the metal release. Iron is assumed to play a key role since the amount of secondary iron in the soils is higher than the total load of secondary heavy metals. It can be assumed that most of the heavy metals are initially associated with iron-rich phases through adsorption or coprecipitation. These phases can be dissolved, or associated metals can be desorbed, by a decrease in pH. It would be feasible to further develop a process in technical scale for remediation of metal-contaminated soil, based on microbial metabolite production leading to formation of soluble metal complexes, notably with copper.

  • 14.
    Arwidsson, Zandra
    et al.
    Örebro University, School of Science and Technology. SAKAB AB, Kumla, Sweden.
    Elgh-Dalgren, Kristin
    Örebro University, School of Science and Technology.
    von Kronhelm, Thomas
    SAKAB AB, Kumla, Sweden.
    Sjoberg, Ragnar
    Solvent AB, Motala, Sweden.
    Allard, Bert
    Örebro University, School of Science and Technology.
    van Hees, Patrick A. W.
    Örebro University, School of Science and Technology.
    Remediation of heavy metal contaminated soil washing residues with amino polycarboxylic acids2010In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 173, no 1-3, p. 697-704Article in journal (Refereed)
    Abstract [en]

    Removal of Cu, Pb, and Zn by the action of the two biodegradable chelating agents [S,S]-ethylenediaminedisuccinic acid (EDDS) and methylglycinediacetic acid (MGDA), as well as citric acid, was tested. Three soil samples, which had previously been treated by conventional soil washing (water), were utilized in the leaching tests. Experiments were performed in batches (0.3 kg-scale) and with a WTC-mixer system (Water Treatment Construction, 10 kg-scale). EDDS and MGDA were most often equally efficient in removing Cu, Pb, and Zn after 10-60 min. Nonetheless, after 10 d, there were occasionally significant differences in extraction efficiencies. Extraction with citric acid was generally less efficient, however equal for Zn (mainly) after 10 d. Metal removal was similar in batch and WTC-mixer systems, which indicates that a dynamic mixer system could be used in full-scale. Use of biodegradable amino polycarboxylic acids for metal removal, as a second step after soil washing, would release most remaining metals (Cu, Pb and Zn) from the present soils, however only after long leaching time. Thus, a full-scale procedure, based on enhanced metal leaching by amino polycarboxylic acids from soil of the present kind, Would require a pre-leaching step lasting several days in order to be efficient. (C) 2009 Elsevier B.V. All rights reserved.

  • 15.
    Arwidsson, Zandra
    et al.
    SAKAB AB, Norrtorp, Sweden.
    Ålund, Marie
    SAKAB AB, Norrtorp, Sweden.
    Allard, Bert
    Örebro University, School of Science and Technology.
    Karlsson, Stefan
    Örebro University, School of Science and Technology.
    Metal mobilisation from soils and sediments by hydroxycarboxylic acids of natural origin2011In: 25th International Applied Geochemistry Symposium, 22-26 August, 2011, Rovaniemi, Finland / [ed] Pertti Sarala, V. Juhani Ojala, Marja-Leena Porsanger, 2011, p. 77-77Conference paper (Refereed)
  • 16.
    Ashhami, Arnavaz
    Örebro University, School of Science and Technology.
    Assessment of Extractable Organic Fluorine (EOF) Content and Contribution of Per- and Polyfluoroalkyl Substances (PFASs) in Cosmetic Products2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Per- and polyfluoroalkyl substances (PFASs) are a large group of compounds consisting of a fully or partially fluorinated alkyl chain and a functional head group. The structure of PFASs yields molecules that are highly desired in both industrial and commercial applications were properties such as oil and water repellency are needed. However PFASs have also been linked to health problems such as cancer, hepatoxicity and reproductive toxicity. Recently the analysis of total organic fluorine (TOF) and PFASs in several matrices have revealed the presence of unidentified organofluorine (OF) compounds. In addition fluorinated compounds have been identified in various personal care products (PCPs).

    The aim of this study was to quantify the extractable organic fluorine (EOF) content and contribution of individual PFASs in various cosmetic products in order to determine the amount of unidentified OF and asses the possibility of a risk to human health. Determination of EOF was conducted using combustion ion chromatography (CIC) and followed up through target analysis by liquid chromatography tandem-mass spectrometry (LC-MS/MS).

    Fluorinated compounds were detected in 21 of the 32 analyzed samples in concentrations ranging up to 242 μg/g. Target analysis established polyfluoroalkyl phosphate esters (PAPs) as the main contributing compounds to total PFASs, followed by perfluoroalkyl carboxylic acids (PFCAs). In addition perfluoroalkyl sulfonic acids (PFSAs) and fluorotelomer sulfonic acids (FTSAs) were detected. Unidentified OF ranged from 53-100% in a majority of the samples. In addition the study was able to confirm the presence of fluorinated compounds other than those declared on the product labels.

    The results suggest cosmetic products as a possible contributing source to total PFAS exposure, making their presence a possible concern to human health. Further studies are required to assess the risk.

  • 17.
    Au Musse, Ayan
    Örebro University, School of Science and Technology.
    Characterization of the metabolic changes in chicken liver due to exposure of perfluorooctane sulfonate (PFOS) during the embryo development2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Perfluoroalkyl substances (PFASs) are anthropogenic compounds that have been classed as persistent organic pollutants (POPs) and are found in both commercial and industrial products. PFASs have been detected in different environmental matrices and have been found to bioaccumulate in all trophic levels. The adverse effects that are associated with PFAS exposure include reduced body weight, increased liver weight, hepatocellular hypertrophy, a decrease in serum cholesterol and triglycerides. This project aims to characterize the metabolic changes in lipid metabolism in the liver after exposure to one of the well-studied PFASs, the perfluorooctane sulfonate (PFOS), during the embryo development using the domestic chicken as a model organism.

    The characterization of the metabolic changes was done by conducting both quantitative lipidomic analysis and semi-quantitative global profiling on extracted lipids from liver homogenates from a former related project looking at fatty acid profiles. The extracted lipids were analyzed using UHPLC/Q-TOF-MS. In the quantitative analysis, the PFOS-treated groups (0.1 ug/g and 1.0 ug/g)exhibited higher lipid concentrations when compared with the solvent control group (5% DMSO) and the untreated group leading to the conclusion that PFOS exposure disrupts the lipid metabolism. When comparing the lipid concentrations between the two PFOS-treated groups (0.1 ug/g and 1.0 ug/g), the majority of the lipids exhibited higher lipid concentrations in the 1.0 ug/g PFOS-treated groups leading to the conclusion that the effect PFOS has on the lipid metabolism is dose dependent. In the global profiling analysis, 63 lipids showed significant differences when comparing the solvent control group with samples either treated with 0.1 ug/g PFOS or 1.0 ug/g PFOS.

  • 18.
    Avakian, Maureen D.
    et al.
    MDB Inc, Research Triangle Park, NC, USA.
    Dellinger, Barry
    Louisiana State Univ, Dept Chem, Baton Rouge, LA, USA.
    Fiedler, Heidelore
    United Nations Environment Program Chemicals, Chatelaine, Switzerland.
    Gullet, Brian
    U.S. Environmental Protection Agency, Research Triangle Park, NC, USA.
    Koshland, Catherine
    School of Public Health, University of California, Berkeley, CA, USA.
    Marklund, Stellan
    Environmental Chemistry, University of Umeå, Umeå, Sweden.
    Oberdorster, Günter
    Department of Environmental Medicine, University of Rochester, New York, USA.
    Safe, Stephen
    Department of Veterinary Physiology and Pharmacology, Texas A&M University, Texas , USA.
    Sarofim, Adel
    Department of Chemical anf Fuels Engineering, University of Utah, Salt Lake City, Utah, USA.
    Smith, Kirk R.
    Environmental Health Sciences, University of California, Berkeley, California, USA.
    Schwartz, David
    Duke University Medical Center, Durham, North Carolina, USA.
    Suk, William A.
    National Institute of Environmental Health Sciences, Resaearc Triangle Park, North Carolina, USA.
    The origin, fate, and health effects of combustion by-products: A research framework2002In: Journal of Environmental Health Perspectives, ISSN 0091-6765, E-ISSN 1552-9924, Vol. 110, no 11, p. 1155-1162Article in journal (Refereed)
    Abstract [en]

    Incomplete combustion processes can emit organic pollutants, metals, and fine particles. Combustion by-products represent global human and environmental health challenges that are relevant not only in heavily industrialized nations, but also in developing nations where up to 90% of rural households rely on unprocessed biomass fuels for cooking, warmth, and light. These issues were addressed at the Seventh International Congress on Combustion BY-Products, which convened 4-6 June 2001 in Research Triangle Park, North Carolina. This congress included a diverse group of multidisciplinary researchers and practitioners who discussed recent developments and future goals in the control of combustion by-products and their effects of exposure on human and ecologic health. Participants recommended that interdisciplinary, coordinated research efforts should be focused to capitalize on the important potential synergisms between efforts to reduce the adverse human health effects linked to exposures to combustion by-products and broader efforts to reduce greenhouse gas emissions and save energy through efficiency. In this article we summarize the principal findings and recommendations for research focus and direction.

  • 19.
    Ax, Erika
    et al.
    Uppsala Univeristy, Sweden.
    Salihovic, Samira
    Örebro University, School of Science and Technology.
    Lind, P. Monica
    Occupational & Environmental Medicine UU, Sweden.
    van Bavel, Bert
    Örebro University, School of Science and Technology.
    Lind, Lars
    Acute & Internal Medicine, UU, Sweden.
    Lampa, Erik
    Occupational & Environmental Medicine UU, Sweden.
    Sjögren, Per
    Clinical Nutrition & Metabolism, UU, Sweden.
    Circulating levels of environmental contaminants are associated with dietary pattern2012In: Toxicology Letters, ISSN 0378-4274, E-ISSN 1879-3169, Vol. 211, no Supplement, p. S101-S101Article in journal (Refereed)
  • 20. Ax, Erika
    et al.
    Sjögren, Per
    Lind, P. Monica
    Lampa, Erik
    Salihovic, Samira
    Örebro University, School of Science and Technology.
    van Bavel, Bert
    Örebro University, School of Science and Technology.
    Lind, Lars
    Dietary pattern affects blood levels of environmental pollutants in elderly Swedish men and women2011In: Annals of Nutrition and Metabolism, ISSN 0250-6807, E-ISSN 1421-9697, Vol. 58, no Suppl. 3, p. 59-60Article in journal (Refereed)
  • 21.
    Berg, Isabelle
    Örebro University, School of Science and Technology.
    Validation of MP-AES at the Quantification of Trace Metals in Heavy Matrices with Comparison of Performance to ICP-MS2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The MP-AES 4200 using microwave plasma and an atomic emission spectroscopy detector provide a new and improved instrument to the analytical field. In this project will the performance of the equipment be evaluated in controlled NaCl-heavy matrices for selected metals (Cu, Zn, Li) and the result from this will be used to optimize a method for specific samples. These samples consist of combustion ashes from the incineration of hazardous waste and are provided by the company SAKAB AB. The sample preparation consisted of several cycles of L/S 10 followed by microwave assisted dissolution with concentrated HNO3, aqua regia or 18.2 MΩ. An extended amount of metals were quantified for these samples (Al, As, Ba, Ca, Cd, Cr, Cu, Fe, K, Li, Mn, Na, Ni, Pb, V, Zn) and most (not Ca, Li, K or Na) were compared with an ICP-MS instrument equipped with a collision cell used for the elements As, Fe and V. A final experiment was made on an L/S 10 of the samples to attempt to separate the metals from the salt with ion exchange, something that would make it possible to recycle this otherwise unused waste.

    The detection limits were all in the low μg L-1 except for Cd, Mn and Zn, which were between 2-4 μg L-1. The MP-AES was found to be able to handle matrices up to 5 g L-1 NaCl without a significant loss of response and provided near identical results to the ICP-MS for the elements that could be compared, this did not included the elements not quantified with the ICP-MS or V which was the only element under the limit of detection for the MP-AES. The experiment where an attempt was made to separate the metals from the salt was proven successful after treatment of bark compost and another type of waste ash as cation exchangers.

  • 22.
    Bergman, Malin
    Örebro University, School of Science and Technology.
    Determination of Polyoxymethylene (POM): Water Partition Coefficients for Alkylated Polycyclic Aromatic Hydrocarbons by Use of GC/MS2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Methods to measure the concentration of freely dissolved PAHs in pore water have been developed and are based on the usage of passive samplers, in this case polyoxymethylene (POM). Spiked samples (containing PAHs with 4-5 rings, methylated PAHs with 2-5 rings and dibenzothiophenes in three different concentrations) were placed on an end-over-end shaker for 28 days, to obtain equilibrium between the amount of PAHs accumulated on the POM strips and the amount of PAHs freely dissolved in the water. Four samples (medium concentration) were removed from the shaker after 7 and 14 days, respectively, and after 28 days were 12 samples (low, medium and high concentrations) removed. The variance of the average log(KPOM) values obtained from medium concentration were statistically tested, and showed that the coefficients for all compounds did not differ significantly over time. The coefficient difference between the three concentrations for the methylated PAHs were greater amongst the more hydrophobic compounds; 7,12-Dimethylbenz(a)anthracene had log(KPOM) of 5.64, 2.77 and 3.71 (low, medium, high). The hydrophilic compounds had coefficients that were more similar in the three concentrations; 1,6-Dimethylnaphthalene had log(KPOM) of 3.80, 2.62, and 3.39 (low, medium, high). Previous studies have determined log(KPOM) for several PAHs, and merged log(KPOM) for alkylated isomeric PAHs. The coefficients from the lowest concentration of serval methylated PAHs and Benzo(e)pyrene were similar to log(KPOM) values obtained for those compounds in an earlier study. The accuracy of risk assessments of PAH contaminated areas will increase when analysing individual methylated PAHs and using individual KPOM values for methylated PAHs, as in this study, instead of merged coefficients.

  • 23.
    Bergman, Malin
    Örebro University, School of Science and Technology.
    Trophic transfer of per- and polyfluoroalkyl substances (PFASs) by glacial relicts in Lake Vättern, Sweden2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The aim with the study was to assess if glacial relict amphipods constitute as vectors of transport of per- and polyfluoroalkyl substances (PFASs) in the Arctic char food web in Lake Vättern, Sweden. Sediment, surface water and biota samples were analysed for PFASs using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), and stable isotope analysis of δ 13C and δ15N was performed on sediments and biota samples. Sediment samples (n=3) were suggested to have PFASs originating from different sources. Generally low concentrations were detected in sediment (sum of all detected PFASs were 2.7 ng/g in St. Aspön, 2.9 ng/g in Visingsö and 0.6 ng/g in Omberg, reported in dry weight), compared to biota and several water samples. The PFAS distribution and concentrations in the samples representing St. Aspön and Visingsö deviated from the third sample from Omberg, which was further evidenced by stable isotope analysis. The average concentration of all detected PFASs in the potentially low contaminated samples was 6 ng/L, while it was 5900 ng/L in the potentially aqueous film forming foam (AFFF) contaminated samples. Surface water samples from Jönköping airport and Kärnebäcken measured concentrations of linear perfluorooctane sulfonate (L-PFOS) that all exceeded the Annual Average Environmental Quality Standard (AA-EQS) value of 0.65 ng/L of PFOS in freshwater (fire pond: 14 000 ng/L, ditch: 600 ng/L, Sandserydsån: 160 ng/L, Kärnebäcken: 150 ng/L). A reference sample that was assumed to represent diffuse sources showed similar distribution of PFASs as in several estuaries around Lake Vättern. Since the surface area of Lake Vättern is large (1900 km2), atmospheric deposition is suggested as one of the major contamination sources. This should be further investigated to better assess the local environmental burden. Trophic magnification factors (TMFs) calculated for L-PFOS, perfluorononaoate (PFNA) and perfluorotridecanoate (PFTrDA) were > 1, indicating biomagnification to higher trophic levels. Among all detected PFASs in biota samples, L-PFOS was the most prominent component (58 %), followed by PFTrDA (20 %), PFNA (6.7 %), perfluoroundecanoate (PFUnDA) (5.3 %), perfluorodecanoate (PFDA) (4.9 %) and perfluorooctanoate (PFOA) (2.9 %). Highest concentrations of all targeted compounds (ΣPFAS 220 ng/g) were detected in Monoporeia, the smallest of amphipods. Contamination profiles of perfluorinated carboxylates (PFCAs) showed similar patterns for several species as those derived in another study from Lake Ontario. Mainly Monoporeia and Pallasea, but partly also Mysis are potential vectors of trophic transport of PFASs in Lake Vättern, although further investigations should be conducted including additional replicates and species. Glacial relict crustaceans are sensitive to pollution in a system, and several fish species 3 in the present study had concentrations of L-PFOS above the AA-EQS value of 9.1 ng/g in fish, thus indicating PFAS contamination. Since many fish species feed on glacial relicts, contamination of these amphipods will transfer PFASs further in the Arctic char food web and could thus affect the whole eco-system in Lake Vättern.

  • 24.
    Bjurlid, Filip
    Örebro University, School of Science and Technology.
    Polybrominated dibenzo-p-dioxins and furans: from source of emission to human exposure2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Brominated flame retardants (BFRs), which are ubiquitous in modern life and the environment, are the major source for polybrominated dibenzo-p-dioxins and furans (PBDD/Fs). The knowledge about PBDD/Fs is lim-ited compared to other environmental pollutants, even though PBDD/Fs show similar toxicity as polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) which are considered to be among the most toxic man-made substances. The aim of the thesis was to provide a better understanding of PBDD/Fs by investigating the occurrence and distribution of PBDD/Fs in the following matrices: soot and gas from an accidental fire site which is a typical source of emission, blubber from marine mammals living in both far remote areas as well as areas close to anthropogenic sources, and finally in human milk from ten nursing mothers.

    PBDD/Fs was detected in blubber from pilot whales sampled around Faroe Islands, which proved the occurrence in marine mammals in a far remote area. The findings of PBDD/Fs in blubber from Baltic ringed seals showed slightly higher concentrations compared to the pilot whales, which is expected since the Baltic Sea in among the world’s most contam-inated water areas. In the pilot whales and the ringed seals, the average contribution from PBDD/Fs to the total (PCDD/F+PBDD/F) Total Equiv-alent Quantity (TEQ) was low, (1-8%). In gas and soot samples from the accidental fire site, PBDD/Fs were detected in all samples and the contri-bution of PBDD/Fs to the total TEQ was close to 100%. In the human milk samples, PBDD/Fs were detected in all samples and the average con-tribution of PBDD/Fs to the total TEQ was 40%. The results indicate that PBDD/Fs are of concern for human exposure, and should be monitored together with PCDD/Fs in future studies. Moreover, the occurrence at ac-cidental fire sites indicate that PBDD/Fs are a source for occupational ex-posure for firefighters and other professionals. The impact from PBDD/Fs on marine mammalians seems to be of less concern.

    List of papers
    1. Occurrence of brominated dioxins in a study using various firefighting methods
    Open this publication in new window or tab >>Occurrence of brominated dioxins in a study using various firefighting methods
    2017 (English)In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 599-600, p. 1213-1221Article in journal (Refereed) Published
    Abstract [en]

    The use of different firefighting methods influences how fast a fire is extinguished and how fast the temperature drops in the area affected by the fire. These differences may also influence the formation of harmful pollutants during firefighting of an accidental fire. The aim was to study occurrence of brominated dibenzo-p-dioxins and furans (PBDD/Fs) in gas and soot during five fire scenarios resembling a small apartment fire and where different firefighting methods were used. Samples of gas and soot were taken both during the buildup of the fire and during the subsequent extinguishing of the fire while using different firefighting methods (nozzle, compressed air foam system, cutting extinguisher) and an extinguishing additive. New containers equipped with identical sets of combustible material were used for the five tests. The use of different firefighting methods and extinguishing additive induced variations in concentration and congener profiles of detected PBDD/Fs. The concentration range of Sigma PBDD/Fs in gas was 4020-18,700 pg/m(3), and in soot 76-4092 pg/m(2). PBDFs were the predominant congeners and 1,2,3,4,6,7,8-HpBDF was the most abundant congener. Chlorinated dibenzo-p-dioxins and furans (PCDD/Fs) were also monitored. The PBDD/Fs contributed with in average 97% to the total (PCDD/Fs plus PBDD/Fs) toxic equivalents, in soot and gas. During extinguishing, the shorter time the temperature was around 300 degrees C, the lower occurrence of PBDD/Fs. In the study the firefighting methods showed a difference in how effectively they induced a temperature decrease below 300 degrees C in the fire zone during quenching, where cutting extinguishing using additive and the compressed air foam system showed the fastest drop in temperature.

    Place, publisher, year, edition, pages
    Elsevier, 2017
    Keywords
    PBDD/F, PCDD/F, Fire, Cutting extinguisher, Foam, Additive, Nozzle, Formation
    National Category
    Environmental Sciences
    Research subject
    Enviromental Science
    Identifiers
    urn:nbn:se:oru:diva-59123 (URN)10.1016/j.scitotenv.2017.05.087 (DOI)000405253500018 ()28514839 (PubMedID)2-s2.0-85019068316 (Scopus ID)
    Funder
    Swedish Civil Contingencies Agency
    Available from: 2017-08-22 Created: 2017-08-22 Last updated: 2017-12-18Bibliographically approved
    2. Occurrence of polybrominated dibenzo-p-dioxins, dibenzofurans (PBDD/Fs) and polybrominated diphenyl ethers (PBDEs) in pilot whales (Globicephala melas) caught around the Faroe Islands
    Open this publication in new window or tab >>Occurrence of polybrominated dibenzo-p-dioxins, dibenzofurans (PBDD/Fs) and polybrominated diphenyl ethers (PBDEs) in pilot whales (Globicephala melas) caught around the Faroe Islands
    2018 (English)In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 195, p. 11-20Article in journal (Refereed) Published
    Abstract [en]

    Blubber from Faroese pilot whales (Globicephala melas) was analysed for brominated dioxins PBDD/Fs, with a subset also analysed for chlorinated dioxins, PCDD/Fs. The studied individuals were restricted to juvenile male whales sampled in the Faroe Islands during the period 1997–2013. Among the PBDD/Fs, the furans were predominant, although the relative abundance of various congeners differed between samples. Furans accounted for, on average, 79% of the ∑PBDD/Fs in the samples, with 1,2,3,4,6,7,8-HpBDF the most abundant congener, found in half of the analysed pilot whales. The concentration range for ∑PBDD/Fs among the samples was 0.080–71 pg/g l.w. (lipid weight), and the sum of toxic equivalents ranged from 0.0039 to 4.7 pg TEQ/g l.w. No relationship was found between PBDD/Fs and PCDD/Fs. In addition, 20 pilot whale samples from the period 2010–2013 were analysed for PBDEs. Several PBDE congeners were found in all of the sampled pilot whales, and at noticeably higher levels than PBDD/Fs and PCDD/Fs. The ∑PBDEs ranged from 140 to 1900 ng/g l.w., with BDE #47 the most abundant congener detected in the samples. Results from the present study were then compared with data from previous studies on pilot wales to investigate temporal trends between 1986 and 2013. The comparison indicated that PBDE concentrations in juvenile males have decreased from 1996 to the latest observations in 2013. No relationship between the concentration levels of PBDD/Fs and PBDEs in the sampled pilot whales could be identified, which indicates possible differences in the metabolism of, or exposure to, PBDEs and PBDD/Fs.

    Place, publisher, year, edition, pages
    Elsevier, 2018
    Keywords
    PBDD/Fs, PBDEs, PCDD/Fs, Pilot whale blubber, Faroe Islands
    National Category
    Other Chemistry Topics Environmental Sciences
    Identifiers
    urn:nbn:se:oru:diva-63414 (URN)10.1016/j.chemosphere.2017.12.044 (DOI)000424172400002 ()29248748 (PubMedID)2-s2.0-85037990841 (Scopus ID)
    Note

    Funding Agency:

    Danish Environmental Protection Agency as part of the environmental support program Dancea - Danish Cooperation for Environment in the Arctic

    Available from: 2017-12-18 Created: 2017-12-18 Last updated: 2018-02-22Bibliographically approved
    3. Temporal trends of PBDD/Fs, PCDD/Fs, PBDEs and PCBs in ringed seals from the Baltic Sea (Pusa hispida botnica) between 1974 and 2015
    Open this publication in new window or tab >>Temporal trends of PBDD/Fs, PCDD/Fs, PBDEs and PCBs in ringed seals from the Baltic Sea (Pusa hispida botnica) between 1974 and 2015
    2018 (English)In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 616-617, p. 1374-1383Article in journal (Refereed) Published
    Abstract [en]

    Temporal trends in exposure to persistent organic pollutants (POPs) were assessed in 22 pooled samples gathered from 69 individuals of Baltic ringed seal (Pusa hispida botnica) from 1974 to 2015. Samples were analysed for polybrominated dibenzo-p-dioxins and furans (PBDD/Fs), polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs). No previous study has reported on the occurrence of PBDD/Fs in marine mammals in the Baltic Sea. Concentrations of pollutants in Baltic ringed seal, a marine mammal and top predator, can be used as an indicator of pollutants concentrations in the Baltic region.

    Visual inspection of data did not show any temporal trends for PBDD/Fs, while the PCDD/Fs and PCBs showed decreasing concentrations between 1974 and 2015. PBDEs increased until the end of the 1990s and then decreased until the end of the period. ∑ PBDD/Fs ranged from 0.5–52.3 pg/g lipid weight (l.w.) (0.08–4.8 pg TEQ/g l.w.), with 1,2,3,4,6,7,8-HpBDF contributing on average 61% to ∑ PBDD/Fs. ∑ PCDD/Fs ranged from 103 to 1480 pg/g l.w. (39–784 pg TEQ/g l.w.), with 1,2,3,6,7,8-HxCDD, 1,2,3,7,8-PeCDD and 2,3,4,7,8-PeCDF showing the highest average concentrations. PBDD/F toxic equivalents (TEQ) contributed on average 1.1% to the total (PBDD/F + PCDD/F) TEQ. The ∑ PBDEs concentration range was 18.7–503 ng/g l.w., with BDE #47 the predominant congener. The concentration range for ∑ PCBs was 2.8–40.1 μg/g l.w., with #138 and #153 the most abundant congeners. Visual inspection of the data showed decreasing concentrations for all compound groups except PBDD/Fs. A slight increase in the PBDD/Fs concentrations was observed from 2004 onwards. This observation needs to be investigated further.

    Place, publisher, year, edition, pages
    Elsevier, 2018
    Keywords
    Dioxins, Furans, POPs, Marine mammal
    National Category
    Other Chemistry Topics Environmental Sciences
    Identifiers
    urn:nbn:se:oru:diva-63413 (URN)10.1016/j.scitotenv.2017.10.178 (DOI)000424121800137 ()29066193 (PubMedID)2-s2.0-85038955003 (Scopus ID)
    Note

    Funding Agency:

    Swedish Environmental Protection Agency  2213-15-022

    Available from: 2017-12-18 Created: 2017-12-18 Last updated: 2018-02-22Bibliographically approved
    4. Polybrominated dibenzo-p-dioxins and dibenzofurans and Stockholm Convention POPs in human milk: evaluation of the effects of breastfeeding duration
    Open this publication in new window or tab >>Polybrominated dibenzo-p-dioxins and dibenzofurans and Stockholm Convention POPs in human milk: evaluation of the effects of breastfeeding duration
    (English)Manuscript (preprint) (Other academic)
    National Category
    Other Chemistry Topics
    Identifiers
    urn:nbn:se:oru:diva-63415 (URN)
    Available from: 2017-12-18 Created: 2017-12-18 Last updated: 2017-12-18Bibliographically approved
  • 25.
    Bjurlid, Filip
    et al.
    Örebro University, School of Science and Technology.
    Dam, Maria
    Environment Agency, Argir, Faroe Islands.
    Hoydal, Katrin
    Environment Agency, Argir, Faroe Islands.
    Hagberg, Jessika
    Örebro University, School of Science and Technology. Department of Occupational and Environmental Medicine, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
    Occurrence of polybrominated dibenzo-p-dioxins, dibenzofurans (PBDD/Fs) and polybrominated diphenyl ethers (PBDEs) in pilot whales (Globicephala melas) caught around the Faroe Islands2018In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 195, p. 11-20Article in journal (Refereed)
    Abstract [en]

    Blubber from Faroese pilot whales (Globicephala melas) was analysed for brominated dioxins PBDD/Fs, with a subset also analysed for chlorinated dioxins, PCDD/Fs. The studied individuals were restricted to juvenile male whales sampled in the Faroe Islands during the period 1997–2013. Among the PBDD/Fs, the furans were predominant, although the relative abundance of various congeners differed between samples. Furans accounted for, on average, 79% of the ∑PBDD/Fs in the samples, with 1,2,3,4,6,7,8-HpBDF the most abundant congener, found in half of the analysed pilot whales. The concentration range for ∑PBDD/Fs among the samples was 0.080–71 pg/g l.w. (lipid weight), and the sum of toxic equivalents ranged from 0.0039 to 4.7 pg TEQ/g l.w. No relationship was found between PBDD/Fs and PCDD/Fs. In addition, 20 pilot whale samples from the period 2010–2013 were analysed for PBDEs. Several PBDE congeners were found in all of the sampled pilot whales, and at noticeably higher levels than PBDD/Fs and PCDD/Fs. The ∑PBDEs ranged from 140 to 1900 ng/g l.w., with BDE #47 the most abundant congener detected in the samples. Results from the present study were then compared with data from previous studies on pilot wales to investigate temporal trends between 1986 and 2013. The comparison indicated that PBDE concentrations in juvenile males have decreased from 1996 to the latest observations in 2013. No relationship between the concentration levels of PBDD/Fs and PBDEs in the sampled pilot whales could be identified, which indicates possible differences in the metabolism of, or exposure to, PBDEs and PBDD/Fs.

  • 26.
    Bjurlid, Filip
    et al.
    Örebro University, School of Science and Technology.
    Hagberg, Jessika
    Örebro University, School of Science and Technology. Department of Occupational and Environmental Medicine, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
    Polybrominated dibenzo-p-dioxins and dibenzofurans and Stockholm Convention POPs in human milk: evaluation of the effects of breastfeeding durationManuscript (preprint) (Other academic)
  • 27.
    Bjurlid, Filip
    et al.
    Örebro University, School of Science and Technology.
    Roos, Anna
    Department of Environmental Research and Monitoring, Swedish Museum of Natural History, Stockholm, Sweden.
    Ericson Jogsten, Ingrid
    Örebro University, School of Science and Technology.
    Hagberg, Jessika
    Örebro University, School of Science and Technology. Department of Occupational and Environmental Medicine, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
    Temporal trends of PBDD/Fs, PCDD/Fs, PBDEs and PCBs in ringed seals from the Baltic Sea (Pusa hispida botnica) between 1974 and 20152018In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 616-617, p. 1374-1383Article in journal (Refereed)
    Abstract [en]

    Temporal trends in exposure to persistent organic pollutants (POPs) were assessed in 22 pooled samples gathered from 69 individuals of Baltic ringed seal (Pusa hispida botnica) from 1974 to 2015. Samples were analysed for polybrominated dibenzo-p-dioxins and furans (PBDD/Fs), polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs). No previous study has reported on the occurrence of PBDD/Fs in marine mammals in the Baltic Sea. Concentrations of pollutants in Baltic ringed seal, a marine mammal and top predator, can be used as an indicator of pollutants concentrations in the Baltic region.

    Visual inspection of data did not show any temporal trends for PBDD/Fs, while the PCDD/Fs and PCBs showed decreasing concentrations between 1974 and 2015. PBDEs increased until the end of the 1990s and then decreased until the end of the period. ∑ PBDD/Fs ranged from 0.5–52.3 pg/g lipid weight (l.w.) (0.08–4.8 pg TEQ/g l.w.), with 1,2,3,4,6,7,8-HpBDF contributing on average 61% to ∑ PBDD/Fs. ∑ PCDD/Fs ranged from 103 to 1480 pg/g l.w. (39–784 pg TEQ/g l.w.), with 1,2,3,6,7,8-HxCDD, 1,2,3,7,8-PeCDD and 2,3,4,7,8-PeCDF showing the highest average concentrations. PBDD/F toxic equivalents (TEQ) contributed on average 1.1% to the total (PBDD/F + PCDD/F) TEQ. The ∑ PBDEs concentration range was 18.7–503 ng/g l.w., with BDE #47 the predominant congener. The concentration range for ∑ PCBs was 2.8–40.1 μg/g l.w., with #138 and #153 the most abundant congeners. Visual inspection of the data showed decreasing concentrations for all compound groups except PBDD/Fs. A slight increase in the PBDD/Fs concentrations was observed from 2004 onwards. This observation needs to be investigated further.

  • 28. Björkblom, Carina
    et al.
    Olsson, Per-Erik
    Örebro University, Department of Natural Sciences.
    Katsiadaki, I
    Wiklund, T
    Estrogen- and androgen-sensitive bioassays based on primary cell and tissue slice cultures from three-spined stickleback (Gasterosteus aculeatus)2007In: Comparative Biochemistry and Physiology Part C: Toxicology & Pharmacology, ISSN 1532-0456, Vol. 146, no 3, p. 431-442Article in journal (Refereed)
    Abstract [en]

    Endocrine disrupting compounds are chemicals that may interfere with the endocrine system causing severe effects in organisms. The three-spined stickleback (Gasterosteus aculeatus L.) offers a potential for the assessment of endocrine disruption caused by a) estrogenic xenobiotics through the estrogen-dependent protein vitellogenin and b) androgenic xenobiotics through the androgen-dependent protein spiggin. The stickleback is presently the only known fish species with a quantifiable androgen and anti-androgen biomarker endpoint. In the current study, hepatocyte and kidney primary cell cultures and liver and kidney tissue slice cultures were prepared and used for detecting estrogenic or androgenic activity in vitro through the action of hormones or municipal sewage water. The results indicate that stickleback male hepatocyte cultures are suitable in detecting estrogenic activity and stickleback female kidney tissue slice cultures in detecting androgenic activity. The tested sewage water showed high estrogenic activity but no significant androgenic activity. Primary cell and tissue slice cultures isolated from the three-spined stickleback will allow simultaneously screening in vitro for potential estrogenic and androgenic activity of complex samples.

  • 29.
    Björklund, Sofie
    Örebro University, School of Science and Technology.
    Validation of a Cleanup Method for Analysis of Novel Brominated Flame Retardants in Biota Matrices Sofie Björklund 2015-05-30 Supervisors Ingrid Ericson2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Brominated flame retardants is a group of compounds present in numerous types of materials in our surroundings. Although their purpose is to slow the progression of a fire, many has been shown to be toxic to the environment. Novel brominated flame retardants have been introduced to the market as old ones have been removed. Reliable methods are crucial to be able to monitor how the novel brominated flame retardant spread and accumulate in the environment. To achieve this, a method validation of a cleanup method using multilayer silica followed by analysis by atmospheric pressure gas chromatography coupled to tandem mass spectroscopy was performed. This method had been previously used for polybrominated diphenyl ethers and the aim was to see if it could be used for analysis of novel brominated flame retardants as well. Spiking experiments showed generally good results, with recoveries of the native compound ranging from 40% to 174%.

    To apply the method on real matrix samples, eight samples of osprey eggs and five samples of adipose tissue of ringed seal was analyzed. Several novel brominated flame retardants were found, most abundant being the methoxylated polybrominated diphenyl ethers. Dominant congener was 2'-Methoxy-2,3',4,5'-tetrabromodiphenyl ether (2PMBDE#68) followed by 6-Methoxy-2,2',4,4'-tetrabromodiphenyl ether (6PMBDE#47), 5-Methoxy-2,2',4,4'-tetrabromodiphenyl ether (5PMBDE#47) and 5-Methoxy-2,2',4,4',6-pentabromodiphenyl ether (5PMBDE#100) with concentrations ranging from <0,13-13 ng/g lipid weight in osprey eggs and <0,003-249 ng/g lipid weight in ringed seal blubber. Also 1,2-Bis(2,4,6-tribromophenoxy)ethane and pentabromobenzene were found in both osprey eggs and ringed seal blubber. Hexabromobenzene was found in ringed seal blubber and 2,3,5,6-tetrabromo-p-xylene was identified in osprey eggs.

  • 30.
    Björnsdotter, Maria
    Örebro University, School of Science and Technology.
    Leaching of Residual Monomers, Oligomers and Additives from Polyethylene, Polypropylene, Polyvinyl Chloride, High-density Polyethylene and Polystyrene Virgin Plastics2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Plastic debris are accumulating in our oceans and are degraded into smaller pieces which eventually becomes small enough to be available to lower thropic level organisms. Microplastics, commonly defined as plastic particles <5 mm, are globally distributed and found at remote locations far away from industrialized and populated areas. The effects of macro sized plastics is well understood whilst the effects of microplastics is hard to predict. It is known that microplastics act as transfer vectors for a wide range of toxic chemicals into organisms, and it is also known that the particle itself can cause toxic responses such as increased immune response and endocrine disruption. Researchers utilize virgin plastic pellets in order to determine the toxicological effect of the plastic particle itself, but resent research suggest that these virgin plastics may release chemicals that contribute to the toxic response and thus complicates the interpretation of the results. In present study, five different virgin plastics were allowed to leach in artificial seawater under conditions that mimic those used in particle toxicity studies. Plastics included were polyethylene, polypropylene, polyvinyl chloride, high-density polyethylene and polystyrene. Leachable monomers and oligomers were found in three of the five plastics tested: polyvinyl chloride, high-density polyethylene and polystyrene. Leached compounds from polyvinyl chloride were not identified due to time limitations. Aliphatic hydrocarbons in the size C14-C22 were leached out from high-density polyethylene in the concentration range 0.47 × 10-3 – 1.13 × 10-3 μg ml-1 within 24 hours. Polystyrene was found to leach styrene monomer which reached a concentration of 0.17 μg ml-1 within 24 hours.

  • 31.
    Black, R. R.
    et al.
    National Research Centre for Environmental Toxicology, The University of Queensland, Coopers Plains, Australia.
    Meyer, C. P. (Mick)
    CSIRO Marine and Atmospheric Research, Aspendale, Australia.
    Touati, A.
    ARCADIS Geraghty and Miller Inc, Research Triangle Park NC, USA.
    Gullett, B. K.
    National Risk Management Research Laboratory, US Environment Protection Agency, Research Triangle Park NC, USA.
    Fiedler, Heidelore
    UNEP Chemicals Branch, Châtelaine (GE), Switzerland.
    Mueller, J. F.
    National Research Centre for Environmental Toxicology, The University of Queensland, Coopers Plains, Australia.
    Emission factors for PCDD/PCDF and dl-PCB from open burning of biomass2012In: Environment International, ISSN 0160-4120, E-ISSN 1873-6750, Vol. 38, no 1, p. 62-66Article in journal (Refereed)
    Abstract [en]

    The Stockholm Convention on Persistent Organic Pollutants includes in its aims the minimisation of unintentional releases of polychlorinated dibenzo-dioxins and dibenzofurans (PCDD/PCDF) and dioxin like PCB (dl-PCB) to the environment Development and implementation of policies to achieve this aim require accurate national inventories of releases of PCDD/PCDF/dl-PCB. To support this objective, the Conference of Parties established a process to review and update the UNEP Standardized Toolkit for Identification and Quantification of Dioxin and Furan Releases. An assessment of all emission inventories was that for many countries open burning of biomass and waste was identified as the major source of PCDD/PCDF releases. However, the experimental data underpinning the release estimates used were limited in number and, consequently, confidence in the accuracy of the emissions predictions was low. There has been significant progress in measurement technology since the last edition of the Toolkit in 2005. In this paper we reassess published emission factors for release of PCDD/PCDF and dl-PCB to land and air.

    In total, four types of biomass and 111 emission factors were assessed. It was found that there are no systematic differences in emission factors apparent between biomass types or fire classes. The data set is best described by a lognormal distribution. The geometric mean emission factors (EFs) for releases of PCDD/PCDF to air for the four biomass classes used in the Toolkit (sugarcane, cereal crops, forest and savannah/grass) are 1.6 mu g TEQ(t fuel)(-1), 0.49 mu g TEQ(t fuel)(-1), 1.0 mu g TEQ(t fuel)(-1) and 0.4 mu g TEQ(t fuel)(-1), respectively. Corresponding EFs for release of PCDD/PCDF to land are 3.0 ng TEQ (kg ash)(-1), 1.1 ng TEQ (kg ash)(-1), 1.1 ng TEQ (kg ash)(-1) and 0.67 ng TEQ (kg ash)(-1). There are now also sufficient published data available to evaluate EFs for dl-PCB release to air for sugarcane, forest and grass/savannah; these are 0.03 mu g TEQ (t fuel)(-1), 0.09 mu g TEQ (t fuel)(-1) and 0.01 mu g TEQ (t fuel)(-1), respectively. The average EF for dl-PCB release to land is 0.19 ng TEQ (kg ash)(-1). Application of these EFs to national emissions of PCDD/PCDF for global estimates from open burning will lower previous estimates of PCDD/PCDF releases to air and to land by 85% and 90%, respectively. For some countries, the ranking of their major sources will be changed and open burning of biomass will become less significant than previously concluded.

  • 32.
    Black, R. R.
    et al.
    The University of Queensland, National Research Centre for Environmental Toxicology, Coopersplains, Australia.
    Meyer, C. P.
    CSIRO Marine and Atmospheric Research, Aspendale Vic, Australia.
    Touati, A.
    ARCADIS Geraghty and Miller, Inc, Research Triangle Park NC, USA.
    Gullett, B. K.
    US Environmental Protection Agency, Office of Research and Development, NRMRL (E343-04), Research Triangle Park NC, USA.
    Fiedler, Heidelore
    UNEP/DTIE Chemicals Branch, Châtelaine GE, Switzerland.
    Mueller, J. F.
    The University of Queensland, National Research Centre for Environmental Toxicology, Coopersplains, Australia.
    Emissions of PCDD and PCDF from combustion of forest fuels and sugarcane: A comparison between field measurements and simulations in a laboratory burn facility2011In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 83, no 10, p. 1331-1338Article in journal (Refereed)
    Abstract [en]

    Release of PCDD and PCDF from biomass combustion such as forest and agricultural crop fires has been nominated as an important source for these chemicals despite minimal characterisation. Available emission factors that have been experimentally determined in laboratory and field experiments vary by several orders of magnitude from <0.51 mu g TEQ(t fuel consumed)(-1) to >1001 mu g TEQ(t fuel consumed)(-1). The aim of this study was to evaluate the effect of experimental methods on the emission factor.

    A portable field sampler was used to measure PCDD/PCDF emissions from forest fires and the same fuel when burnt over a brick hearth to eliminate potential soil effects. A laboratory burn facility was used to sample emissions from the same fuels. There was very good agreement in emission factors to air (EF(Air)) for forest fuel (Duke Forest, NC) of 0.52 (range: 0.40-0.79), 0.59 (range: 0.18-1.2) and 0.75 (range: 0.27-1.2) mu g TEQ(WHO2005) (t fuel consumed)(-1) for the in-field, over a brick hearth, and burn facility experiments, respectively. Similarly, experiments with sugarcane showed very good agreement with EFAir of 1.1 (range: 0.40-2.2), 1.5 (range: 0.84-2.2) and 1.7 (range: 0.34-4.4) mu g TEQ (t fuel consumed)(-1) for in-field, over a brick hearth, open field and burn facility experiments respectively. Field sampling and laboratory simulations were in good agreement, and no significant changes in emissions of PCDD/PCDF could be attributed to fuel storage and transport to laboratory test facilities.

  • 33.
    Bogdal, C.
    et al.
    Institute for Chemical and Bioengineering, Eidgenössische Technische Hochschule Zürich (ETH), Zürich, Switzerland; International Panel on Chemical Pollution, Office ETH Zurich, Zürich, Switzerland.
    Abad, E.
    Laboratory of Dioxins, Department of Environmental Chemistry, IDÆA-CSIC, Barcelona, Spain.
    Abalos, M.
    Laboratory of Dioxins, Department of Environmental Chemistry, IDÆA-CSIC, Barcelona, Spain.
    van Bavel, Bert
    Örebro University, School of Science and Technology.
    Hagberg, Jessika
    Örebro University, School of Science and Technology.
    Scheringer, M.
    Institute for Chemical and Bioengineering, Eidgenössische Technische Hochschule (ETH), Zürich, Switzerland; International Panel on Chemical Pollution, Office ETH Zürich, Switzerland.
    Fiedler, Heidelore
    UNEP Chemicals, Châtelaine GE, Switzerland.
    Worldwide distribution of persistent organic pollutants in air, including results of air monitoring by passive air sampling in five continents2013In: TrAC. Trends in analytical chemistry, ISSN 0165-9936, E-ISSN 1879-3142, Vol. 46, p. 150-161Article in journal (Refereed)
    Abstract [en]

    This article provides an overview of concentrations of persistent organic pollutants (POPs) in ambient air on a global scale, including recent measurements and an extensive compilation of literature data. In this study, passive air samplers (PASs) were successfully employed to assess concentrations of POPs in ambient air from Africa, Latin America, the Caribbean, and the Pacific Islands. The project aimed to extend the knowledge on environmental contamination by POPs in these regions, where the currently available data are still limited to a few monitoring studies.

    The ambient air concentrations of PCB in Africa were relatively high when compared to other regions. Waste, in particular electronic waste, exported to Africa from industrialized countries may be a possible source of PCB in Africa, where PCB have never been extensively used or produced. For DDTs, the wide range of concentrations and particularly high levels in some countries of Africa and the Pacific Islands reflect the use of DDT for malaria control in these regions. For PCDD/PCDF, concentrations in Africa and Latin America are similar to or even higher than in Europe, probably due to unfavorable combustion practices of chlorine-containing materials.

    The data support the needs for further monitoring in developing countries and countries with economies in transition, and action to reduce environmental contamination by, and human exposure to, hazardous chemicals.

  • 34. Borg, O. Anders
    et al.
    Eriksson, Leif A.
    Örebro University, Department of Natural Sciences.
    Durbeej, Bo
    Electron-transfer induced repair of 6-4 photoproducts in DNA: a computational study.2007In: Journal of Physical Chemistry A, ISSN 1089-5639, E-ISSN 1520-5215, Vol. 111, no 12, p. 2351-2361Article in journal (Refereed)
    Abstract [en]

    The mechanism employed by DNA photolyase to repair 6-4 photoproducts in UV-damaged DNA is explored by means of quantum chemical calculations. Considering the repair of both oxetane and azetidine lesions, it is demonstrated that reduction as well as oxidation enables a reversion reaction by creating anionic or cationic radicals that readily fragment into monomeric pyrimidines. However, on the basis of calculated reaction energies indicating that electron transfer from the enzyme to the lesion is a much more favorable process than electron transfer in the opposite direction, it is suggested that the photoenzymic repair can only occur by way of an anionic mechanism. Furthermore, it is shown that reduction of the oxetane facilitates a mechanism involving cleavage of the C−O bond followed by cleavage of the C−C bond, whereas reductive fragmentation of the azetidine may proceed with either of the intermonomeric C−N and C−C bonds cleaved as the first step. From calculations on neutral azetidine radicals, a significant increase in the free-energy barrier for the initial fragmentation step upon protonation of the carbonylic oxygens is predicted. This effect can be attributed to protonation serving to stabilize reactant complexes more than transition structures.

  • 35.
    Boström, Björn
    et al.
    Örebro University, Department of Natural Sciences.
    Comstedt, Daniel
    Örebro University, Department of Natural Sciences.
    Ekblad, Alf
    Örebro University, Department of Natural Sciences.
    Isotope fractionation and 13C enrichment in soil profiles during the decomposition of soil organic matter2007In: Oecologia, ISSN 0029-8549, E-ISSN 1432-1939, Vol. 153, no 1, p. 89-98Article in journal (Refereed)
    Abstract [en]

    The mechanisms behind the 13C enrichment of organic matter with increasing soil depth in forests are unclear. To determine if 13C discrimination during respiration could contribute to this pattern, we compared d13C signatures of respired CO2 from sieved mineral soil, litter layer and litterfall with measurements of d13C and d15N of mineral soil, litter layer, litterfall, roots and fungal mycelia sampled from a 68-year-old Norway spruce forest stand planted on previously cultivated land. Because the land was subjected to ploughing before establishment of the forest stand, shifts in d13C in the top 20 cm reflect processes that have been active since the beginning of the reforestation process. As 13C-depleted organic matter accumulated in the upper soil, a 1.0 o/oo d13C gradient from –28.5 o/oo in the litter layer to –27.6 o/oo at a depth of 2–6 cm was formed. This can be explained by the 1 o/oo drop in d13C of atmospheric CO2 since the beginning of reforestation together with the mixing of new C (forest) and old C (farmland). However, the isotopic change of the atmospheric CO2 explains only a portion of the additional 1.0& increase in d13C below a depth of 20 cm. The d13C of the respired CO2 was similar to that of the organic matter in the upper soil layers but became increasingly 13C enriched with depth, up to 2.5 o/oo relative to the organic matter. We hypothesise that this 13C enrichment of the CO2 as well as the residual increase in d13C of the organic matter below a soil depth of 20 cm results from the increased contribution of 13C-enriched microbially derived C with depth. Our results suggest that 13C discrimination during microbial respiration does not contribute to the 13C enrichment of organic matter in soils. We therefore recommend that these results should be taken into consideration when natural variations in d13C of respired CO2 are used to separate different components of soil respiration or ecosystem respiration.

  • 36.
    Breivik, Knut
    et al.
    Norwegian Institute for Air Research (NILU), Kjeller, Norway.
    Alcock, Ruth
    Environmental Research Solutions, Witherslack, Cumbria, UK.
    Li, Yi-Fan
    Meteorological Service of Canada, Downsview, ON, Canada.
    Bailey, Robert E.
    Bailey Associates, Midland, USA.
    Fiedler, Heidelore
    UNEP Chemicals, Châtelaine (GE), Switzerland.
    Pacyna, Jozef M.
    Norwegian Institute for Air Research (NILU), Kjeller, Norway.
    Primary sources of selected POPs: regional and global scale emission inventories2004In: Environmental Pollution, ISSN 0269-7491, E-ISSN 1873-6424, Vol. 128, no 1-2, p. 3-16Article in journal (Refereed)
    Abstract [en]

    During the last decade, a number of studies have been devoted to the sources and emissions of Persistent Organic Pollutants (POPs) at regional and global scales. While significant improvements in knowledge have been achieved for some pesticides, the quantitative understanding of the emission processes and emission patterns for "non-pesticide" POPs are still considered limited. The key issues remaining for the non-pesticide POPs are in part determined by their general source classification. For industrial chemicals, such as the polychlorinated biphenyls (PCBs), there is considerable uncertainty with respect to the relative importance of atmospheric emissions from various source categories. For PCBs, temperature is discussed as a potential key factor influencing atmospheric emission levels and patterns. When it comes to the unintentional by-products of combustion and industrial processes (PCDD/Fs), there is still a large uncertainty with respect to the relative contribution of emissions from unregulated sources such as backyard barrel burning that requires further consideration and characterisation. For hexachlorobenzene (HCB), the relative importance of primary and secondary atmospheric emissions in controlling current atmospheric concentrations remains one of the key uncertainties. While these and other issues may remain unresolved, knowledge concerning the emissions of POPs is a prerequisite for any attempt to understand and predict the distribution and fate of these chemicals on a regional and global scale as well as to efficiently minimise future environmental burdens.

  • 37.
    Brus, Camilla
    Örebro University, School of Science and Technology.
    Techniques for Determining Alcohol Levels in Wine and Mulled Wine2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of this study is to in cooperation with Grythyttan Vin compare and evaluate the accuracy and precision of the Alcolyzer Wine. The Alcolyzer Wine is a Near Infrared based instrument that was compared to GC-FID, GC-MS and distillation. Samples were taken from cisterns at Grythyttan Vin along with finished product samples. These were then analysed using the mentioned analytical techniques. Multiple improvements can be made for the different techniques, such as use of internal standards. The relative standard deviations are higher than desired. Considering aspects such as precision, accuracy, cost, time consumption and user friendliness the preferred method of use is the Alcolyzer Wine. Even though it has limitations in the need to know sugar content it is the fastest and easiest instrument to use. Further studies have to be made to ensure the accuracy and precision of the GC-MS and the GC-FID.

  • 38. Bunta, Juraj
    et al.
    Dahlberg, Martin
    Eriksson, Leif A.
    Örebro University, Department of Natural Sciences.
    Korolev, Nikolai
    Laaksonen, Aatto
    Lohikoski, Raimo
    Lyubartsev, Alexander
    Pinak, Miroslav
    Schyman, Patric
    Solvating, manipulating, damaging, and repairing DNA in a computer2007In: International Journal of Quantum Chemistry, ISSN 0020-7608, E-ISSN 1097-461X, Vol. 107, no 2, p. 279-291Article in journal (Refereed)
    Abstract [en]

    This work highlights four different topics in modeling of DNA: (i) the importance of water and ions together with the structure and function of DNA; the hydration structure around the ions appears to be the determining factor in the ion coordination to DNA, as demonstrated in the results of our MD simulations; (ii) how MD simulations can be used to simulate single molecule manipulation experiments as a complement to reveal the structural dynamics of the studied biomolecules; (iii) how damaged DNA can be studied in computer simulations; and (iv) how repair of damaged DNA can be studied theoretically.

  • 39.
    Bushnell, Eric A C
    et al.
    University of Windsor, Windsor, ON, N9B 3P4, Canada.
    Erdtman, Edvin
    Örebro University, School of Science and Technology.
    Llano, Jorge
    University of Windsor, Windsor, ON, N9B 3P4, Canada.
    Eriksson, Leif A.
    National University of Ireland, Galway, University Road, Galway, Ireland.
    Gauld, James W.
    University of Windsor, Windsor, ON, N9B 3P4, Canada.
    Computational insights into the first branching point in porphyrin biosynthesis: decarboxylation of ring D in URO–III by Uroporphyrinogen–III DecarboxylaseManuscript (preprint) (Other academic)
  • 40.
    Bushnell, Eric A. C.
    et al.
    Department of Chemistry and Biochemistry, University of Windsor, Windsor ON, Canada.
    Erdtman, Edvin
    Örebro University, School of Science and Technology.
    Llano, Jorge
    Department of Chemistry and Biochemistry, University of Windsor, Windsor ON, Canada.
    Eriksson, Leif A.
    Örebro University, School of Science and Technology.
    Gauld, James W.
    Department of Chemistry and Biochemistry, University of Windsor, Windsor ON, Canada.
    The first branching point in porphyrin biosynthesis: a systematic docking, molecular dynamics and quantum mechanical/molecular mechanical study of substrate binding and mechanism of uroporphyrinogen-III decarboxylase2011In: Journal of Computational Chemistry, ISSN 0192-8651, E-ISSN 1096-987X, Vol. 32, no 5, p. 822-834Article in journal (Refereed)
    Abstract [en]

    In humans, uroporphyrinogen decarboxylase is intimately involved in the synthesis of heme, where the decarboxylation of the uroporphyrinogen-III occurs in a single catalytic site. Several variants of the mechanistic proposal exist; however, the exact mechanism is still debated. Thus, using an ONIOM quantum mechanical/molecular mechanical approach, the mechanism by which uroporphyrinogen decarboxylase decarboxylates ring D of uroporphyrinogen-III has been investigated. From the study performed, it was found that both Arg37 and Arg50 are essential in the decarboxylation of ring D, where experimentally both have been shown to be critical to the catalytic behavior of the enzyme. Overall, the reaction was found to have a barrier of 10.3 kcal mol−1 at 298.15 K. The rate-limiting step was found to be the initial protontransfer from Arg37 to the substrate before the decarboxylation. In addition, it has been found that several key interactions exist between the substrate carboxylate groups and backbone amides of various activesite residues as well as several other functional groups.

  • 41.
    Bäckström, Mattias
    Örebro University, Department of Natural Sciences.
    On the chemical state and mobility of lead and other trace elements at the biogeosphere/technosphere interface2002Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Most inorganic contamination has occurred at the interface between the technosphere and the biogeosphere, even though atmospheric emissions have affected the entire globe. Several human activities now pose a substantial threat towards human health and the ecosystems. It was thus decided to study lead as an element with significant anthropogenic emissions in a variety of sources and environments. Lead and other trace elements were studied in groundwaters used for drinking water, in roadside environments, at a shooting range and in a contaminated lake in order to obtain information about mobility and redistribution in different hydrobiogeochemical environments.

    It was found that 60% of the investigated drilled wells in crystalline bedrock failed to meet international health safety limits. This was mainly due to the presence of enhanced concentrations of fluoride and uranium.

    Along roads the concentrations and massfluxes increased significantly for lead, as well as for otheer elements during the winter. This is most likely due to increased pavement wear as a consequence of studded tires and use of deicing salts. The mobility of trace elements also increased in the roadside soils, threatening the shallow groundwater.

    At the shooting range it was found that the downward migration of lead was greater than expected and equilibrium with cerussite was suggested from solid speciation and geochemical calculations. Antimony was associated with lead and showed, despite differences in chemical properties, a similar distribution pattern. This was due to the fact that the major part of the transport at the shooting range was physical.

    In the contaminated lake, several findings regarding the solid speciation of lead was confirmed and other information about redistribution into the hypolimnion from the sediment was gained.

    List of papers
    1. Chemical character of drinking water from Swedish crystaline bedrock
    Open this publication in new window or tab >>Chemical character of drinking water from Swedish crystaline bedrock
    (English)Manuscript (preprint) (Other academic)
    National Category
    Chemical Sciences
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-15924 (URN)
    Available from: 2011-06-15 Created: 2011-06-15 Last updated: 2017-10-17Bibliographically approved
    2. Speciation of heavy metals in road runoff and roadside total deposition
    Open this publication in new window or tab >>Speciation of heavy metals in road runoff and roadside total deposition
    Show others...
    2003 (English)In: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 147, no 1-4, p. 343-366Article in journal (Refereed) Published
    Abstract [en]

    The concentrations of Cd, Co, Cu, Pb, W and Zn were measured in road runoff and total deposition at two Swedish field sites during one year. It was found that the concentrations of most elements increased significantly during the winter, up to one order of magnitude. For cobalt and tungsten, it was found that around 90% of the total mass transport occurred during the winter, whereas for Cu, Pb, Cd, Zn and Na, the corresponding figures were 70–90, 40–80, 60–90, 50–70 and >99% depending on site specific conditions. The deicing salts (rock salts) did not significantly contribute to the increase in trace element concentrations. Instead, the increased concentrations were due to more intense wearing of the pavement during the winter because of the use of studded tires in combination with the chemical effects caused by the use of deicing salts. New potential elemental markers for roads and traffic are suggested.

    National Category
    Natural Sciences
    Research subject
    Enviromental Science
    Identifiers
    urn:nbn:se:oru:diva-5196 (URN)10.1023/A:1024545916834 (DOI)
    Available from: 2009-01-30 Created: 2009-01-30 Last updated: 2017-12-14Bibliographically approved
    3. Mobilisation of heavy metals by deicing salts in a roadside environment
    Open this publication in new window or tab >>Mobilisation of heavy metals by deicing salts in a roadside environment
    Show others...
    2004 (English)In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 38, no 3, p. 720-732Article in journal (Refereed) Published
    Abstract [en]

    The seasonal variations of some selected heavy metals (Cd, Cu, Pb and Zn) and principal anions in soil solutions were monitored as a function of distance from the road at two field sites in Sweden. During the winter, the conductivity, concentrations of dissolved sodium and chloride increased dramatically due to the application of deicing agents (i.e. NaCl). Due to ion exchange, the pH decreased one unit in the soil solutions, whereas the concentrations of total organic carbon decreased due to coagulation and/or sorption to stationary solids. The heavy metal concentrations increased during the winter, but through different mechanisms. Cadmium concentrations in the aqueous phase increased as a response to ion exchange, possibly also enhanced by the formation of chloride complexes. Similarly, the concentrations of zinc increased, due to ion exchange, with calcium and protons. The mechanisms of mobilisation for copper and lead were not that clear probably due to association with coagulated or sorbed organic matter in combination with colloid dispersion

    National Category
    Natural Sciences
    Research subject
    Enviromental Science
    Identifiers
    urn:nbn:se:oru:diva-5200 (URN)10.1016/j.watres.2003.11.006 (DOI)
    Available from: 2009-01-30 Created: 2009-01-30 Last updated: 2017-12-14Bibliographically approved
    4. Metal leachability and anthropogenic signal in roadside soils estimated from sequential extraction and stable lead isotopes
    Open this publication in new window or tab >>Metal leachability and anthropogenic signal in roadside soils estimated from sequential extraction and stable lead isotopes
    2004 (English)In: Environmental Monitoring & Assessment, ISSN 0167-6369, E-ISSN 1573-2959, Vol. 90, no 1-3, p. 135-160Article in journal (Refereed) Published
    Abstract [en]

    Several roadside soil samples were collected at two field sites in Sweden. They were analysed for total elemental content (using both ICP-MS and XRF) and stable lead isotopes. Extraction with deicing salt solution and sequential extraction were performed in order to elucidate the potential mobility due to the use of deicing agents. The total concentrations of elements, especially lead, have decreased and lead is presently almost at background concentrations (15–51 ppm for surface samples). However, the isotopic signature indicates that old gasoline lead still is left at the site constructed prior to 1975. The field site constructed in 1992 showed, however, no 206Pb/207Pb ratio below 1.14. Only minor amounts were leached using deicing salt solutions; for lead only 0.29%, on average, was extracted indicating that the mobile fraction already was released. Sequential extraction indicated that lead mainly was associated with reducible (34.4%) and oxidisable (35.4%) fractions. Exchangable and acid soluble fractions contained 20.3% while 10.0% was found in the residual fraction. The salt extraction released, however, very low concentrations indicating that most in fraction 1 is acid soluble (e.g. carbonates). Tungsten was also found at high concentrations indicating a possible impact from studded tires. For tungsten the following composition was obtained: residual (48.0%) > oxidisable (47.6%) > reducible (3.3%) > exchangeable/acid soluble (1.1%). From the isotopic studies it was also suggested that the order for incorporating anthropogenic lead into soils is exchangeable/carbonates > (hydr)oxides > organic matter > residual. The multivariate technique principal component analysis (PCA) seems promising for evaluating large sequential extraction datasets.

    National Category
    Chemical Sciences
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-5197 (URN)10.1023/B:EMAS.0000003572.40515.31 (DOI)
    Available from: 2009-01-30 Created: 2009-01-30 Last updated: 2017-12-14Bibliographically approved
    5. Factors affecting the dissolution of lead pellets in natural waters
    Open this publication in new window or tab >>Factors affecting the dissolution of lead pellets in natural waters
    (English)Manuscript (preprint) (Other academic)
    National Category
    Chemical Sciences
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-15925 (URN)
    Available from: 2011-06-15 Created: 2011-06-15 Last updated: 2017-10-17Bibliographically approved
    6. Multielement contamination at a skeet and trap shooting range: I: mobility assessment through sequential extraction
    Open this publication in new window or tab >>Multielement contamination at a skeet and trap shooting range: I: mobility assessment through sequential extraction
    (English)Manuscript (preprint) (Other academic)
    National Category
    Chemical Sciences
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-15926 (URN)
    Available from: 2011-06-15 Created: 2011-06-15 Last updated: 2017-10-17Bibliographically approved
    7. Multielement contamination at a skeet and trap shooting range: II: seasonal and spatial variations in surface and groundwaters
    Open this publication in new window or tab >>Multielement contamination at a skeet and trap shooting range: II: seasonal and spatial variations in surface and groundwaters
    (English)Manuscript (preprint) (Other academic)
    National Category
    Chemical Sciences
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-15928 (URN)
    Available from: 2011-06-15 Created: 2011-06-15 Last updated: 2017-10-17Bibliographically approved
    8. Migration and mobility of lead and antimony from a heavily polluted lake sediment
    Open this publication in new window or tab >>Migration and mobility of lead and antimony from a heavily polluted lake sediment
    (English)Manuscript (preprint) (Other academic)
    National Category
    Chemical Sciences
    Research subject
    Chemistry
    Identifiers
    urn:nbn:se:oru:diva-15929 (URN)
    Available from: 2011-06-15 Created: 2011-06-15 Last updated: 2017-10-17Bibliographically approved
  • 42.
    Bäckström, Mattias
    et al.
    Örebro University, Department of Natural Sciences.
    Bohlin, Hanna
    Karlsson, Stefan
    Örebro University, Department of Natural Sciences.
    Holm, Nils
    Element (Ag, Cd, Cu, Pb, Sb, Tl and Zn), element ratio and lead isotope profiles in a sediment affected by a mining operation episode during the late 19th century2006In: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 177, no 1-4, p. 285-311Article in journal (Refereed)
    Abstract [en]

    Mining operations at Maarsaetter in 1877-81 resulted in increased metal loading to a small lake, notably as sulphidic tailings. The event is taken as an opportunity to study the present environmental impact of a historical single major metal release. Lake water and four sediment cores were sampled and analysed for principal and trace elements in solid and aqueous phases as well as general hydrochemical conditions. Chronologies were determined from super(206)Pb/ super(207)Pb ratios and historical records.Ordinary sedimentation after the event has lead to that the tailings are found as a distinct layer at a depth of 18-22 cm in the sediment. The layer is characterized by elevated metal concentrations in the solid and pore water phases, respectively, circum neutral pH and sulphate concentrations below detection. Geochemical modelling indicated a preference for carbonate equilibrium in the waste while sulphides prevailed above it. It is concluded that the growth of the ordinary sediment on top of the waste has lead to a physicochemical barrier that seals of the waste from the overlying sediment. Chemical or physical rupture of the barrier will release the metals to downstream regions.According to the chronologies at least three sources have contributed to the present elevated levels of metals, in additions to the release of tailings. Copper from a historical blast furnace prior to the event at Maarsaetter, transport from mineralized parts of the watershed and release of contaminated water from present mining operations maintain elevated levels of notably zinc, silver, cadmium and lead. At present less than 10% of the lead content at the sediment/water interface comes from atmospheric deposition. Increased levels of antimony and thallium were not observed prior to ca 1950.

  • 43.
    Bäckström, Mattias
    et al.
    Örebro University, Department of Natural Sciences.
    Börjesson, Erika
    SWECO VBB VIAK, SE-61132 Nykoping, Sweden.
    Karlsson, Stefan
    Örebro University, Department of Natural Sciences.
    Diurnal variations of abiotic parameters in a stream, recipient for drainage water in Ranstad, southwest Sweden2002In: Journal of Environmental Monitoring, ISSN 1464-0325, E-ISSN 1464-0333, Vol. 4, no 5, p. 772-777Article in journal (Refereed)
    Abstract [en]

    During 24 h, water samples were taken for determination of a number of key parameters in a water system containing high concentrations of FeII at circumneutral pH. None of the major constituents (Ca, Mg, Na, K and sulfate) showed diurnal variations, while dissolved oxygen and pH increased during the night. This increase could entirely be explained by the decrease in water temperature. However, the concentration of FeII slightly increased at constant concentration of total Fe during the night, opposite to earlier observations in other systems where the presence of FeII was shown to be controlled by photoreduction. Nocturnal peaks of FeII have also been observed in other systems with high iron concentrations, however, at acidic pH, but without obvious explanation. The mechanisms for this process therefore need further investigation.

  • 44.
    Bäckström, Mattias
    et al.
    Örebro University, Department of Natural Sciences.
    Dario, Mårten
    Örebro University, Department of Natural Sciences.
    Allard, Bert
    Örebro University, Department of Natural Sciences.
    Karlsson, Stefan
    Örebro University, Department of Natural Sciences.
    Effects of a fulvic acid on the adsorption of mercury and cadmium on goethite2003In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 304, no 1-3, p. 257-268Article in journal (Refereed)
    Abstract [en]

    The effects of an aquatic fulvic acid on the pH-dependent adsorption of Hg(II) and Cd(II) to particulate goethite (a-FeOOH) were studied in batch systems. The ionic medium consisted of 0.01 M HClO and the total concentrations 4 of mercury and cadmium were maintained at 10y8 M with 203Hg and 109Cd as tracers. pH In the systems was varied in the range 3–10 by addition of HClO and NaOH.All commercial chemicals were of analytical grade or better. An 4 aquatic fulvic acid (20 ppm), previously isolated and characterised in detail, was used as a model for humic substances and its adsorption to goethite is included in this study. The adsorption of the fulvic acid (20 ppm) onto goethite decreased slowly from 90% at pH 3–7.5 to 10% at pH 10. In systems without fulvic acid the adsorption of mercury increased in a linear fashion from 10% at pH 3 to 70% at pH 10.In the presence of fulvic acid (20 ppm), the adsorption was almost quantitative in the intermediate pH range (pH 5–7), and exceeded 92% over the entire pH range. Thus, association between mercury and the fulvic acid enhanced adsorption in general although the largest impact was found at low pH.Adsorption of cadmium increased from nearly 0 to almost 100% at approximately pH 6. In the presence of fulvic acid, the adsorption increased below pH 7 and decreased above pH 7. The adsorption isotherm for mercury when the concentration was increased from 10y8 to 1.8=10y4 M showed a corresponding increase of K (lyg) up to a total concentration at 10y6 M.At higher mercury concentrations K was lowered. In the presence of fulvic acid the corresponding relationship of K was bi-modal, i.e. high values at low and intermediate concentrations of mercury. This behaviour suggests that in the absence of fulvic acid the adsorption follow the expected behaviour, i.e. adsorption sites with similar affinity for mercury. In the presence of fulvic acid, additional adsorption sites are available by the organic molecule (possibly sulfur groups) when it is associated to the goethite. The adsorption isotherm for cadmium indicates a lowering of K at 10y4 M. Cadmium had no competitive effect on mercury and vice versa. Zinc, however, affected the adsorption of cadmium but not the adsorption of mercury.

  • 45. Bäckström, Mattias
    et al.
    Dario, Mårten
    Örebro University, Department of Natural Sciences.
    Karlsson, Stefan
    Allard, Bert
    Örebro University, Department of Natural Sciences.
    Effects of a fulvic acid on the adsorption of mercury and cadmium on goethite2003In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 304, no 1-3, p. 257-268Article in journal (Refereed)
    Abstract [en]

    The effects of an aquatic fulvic acid on the pH-dependent adsorption of Hg(II) and Cd(II) to particulate goethite (alpha-FeOOH) were studied in batch systems. The ionic medium consisted of 0.01 M HClO(4) and the total concentrations of mercury and cadmium were maintained at 10(-8) M with 203Hg and 109Cd as tracers. pH In the systems was varied in the range 3-10 by addition of HClO(4) and NaOH. All commercial chemicals were of analytical grade or better. An aquatic fulvic acid (20 ppm), previously isolated and characterised in detail, was used as a model for humic substances and its adsorption to goethite is included in this study. The adsorption of the fulvic acid (20 ppm) onto goethite decreased slowly from 90% at pH 3-7.5 to 10% at pH 10. In systems without fulvic acid the adsorption of mercury increased in a linear fashion from 10% at pH 3 to 70% at pH 10. In the presence of fulvic acid (20 ppm), the adsorption was almost quantitative in the intermediate pH range (pH 5-7), and exceeded 92% over the entire pH range. Thus, association between mercury and the fulvic acid enhanced adsorption in general although the largest impact was found at low pH. Adsorption of cadmium increased from nearly 0 to almost 100% at approximately pH 6. In the presence of fulvic acid, the adsorption increased below pH 7 and decreased above pH 7. The adsorption isotherm for mercury when the concentration was increased from 10(-8) to 1.8 x 10(-4) M showed a corresponding increase of K(d) (l/g) up to a total concentration at 10(-6) M. At higher mercury concentrations K(d) was lowered. In the presence of fulvic acid the corresponding relationship of K(d) was bi-modal, i.e. high values at low and intermediate concentrations of mercury. This behaviour suggests that in the absence of fulvic acid the adsorption follow the expected behaviour, i.e. adsorption sites with similar affinity for mercury. In the presence of fulvic acid, additional adsorption sites are available by the organic molecule (possibly sulfur groups) when it is associated to the goethite. The adsorption isotherm for cadmium indicates a lowering of K(d) at 10(-4) M. Cadmium had no competitive effect on mercury and vice versa. Zinc, however, affected the adsorption of cadmium but not the adsorption of mercury.

  • 46.
    Bäckström, Mattias
    et al.
    Örebro University, Department of Natural Sciences.
    Karlsson, Stefan
    Örebro University, Department of Natural Sciences.
    Multielement contamination at a skeet and trap shooting range: I: mobility assessment through sequential extractionManuscript (preprint) (Other academic)
  • 47.
    Bäckström, Mattias
    et al.
    Örebro University, Department of Natural Sciences.
    Karlsson, Stefan
    Örebro University, Department of Natural Sciences.
    Allard, Bert
    Örebro University, Department of Natural Sciences.
    Metal leachability and anthropogenic signal in roadside soils estimated from sequential extraction and stable lead isotopes2004In: Environmental Monitoring & Assessment, ISSN 0167-6369, E-ISSN 1573-2959, Vol. 90, no 1-3, p. 135-160Article in journal (Refereed)
    Abstract [en]

    Several roadside soil samples were collected at two field sites in Sweden. They were analysed for total elemental content (using both ICP-MS and XRF) and stable lead isotopes. Extraction with deicing salt solution and sequential extraction were performed in order to elucidate the potential mobility due to the use of deicing agents. The total concentrations of elements, especially lead, have decreased and lead is presently almost at background concentrations (15–51 ppm for surface samples). However, the isotopic signature indicates that old gasoline lead still is left at the site constructed prior to 1975. The field site constructed in 1992 showed, however, no 206Pb/207Pb ratio below 1.14. Only minor amounts were leached using deicing salt solutions; for lead only 0.29%, on average, was extracted indicating that the mobile fraction already was released. Sequential extraction indicated that lead mainly was associated with reducible (34.4%) and oxidisable (35.4%) fractions. Exchangable and acid soluble fractions contained 20.3% while 10.0% was found in the residual fraction. The salt extraction released, however, very low concentrations indicating that most in fraction 1 is acid soluble (e.g. carbonates). Tungsten was also found at high concentrations indicating a possible impact from studded tires. For tungsten the following composition was obtained: residual (48.0%) > oxidisable (47.6%) > reducible (3.3%) > exchangeable/acid soluble (1.1%). From the isotopic studies it was also suggested that the order for incorporating anthropogenic lead into soils is exchangeable/carbonates > (hydr)oxides > organic matter > residual. The multivariate technique principal component analysis (PCA) seems promising for evaluating large sequential extraction datasets.

  • 48.
    Bäckström, Mattias
    et al.
    Örebro University, Department of Natural Sciences.
    Karlsson, Stefan
    Örebro University, Department of Natural Sciences.
    Allard, Bert
    Örebro University, Department of Natural Sciences.
    Mobilisation of lead: field measurements at a trap range compared to solubility experiments2000Conference paper (Refereed)
  • 49.
    Bäckström, Mattias
    et al.
    Örebro University, Department of Natural Sciences.
    Karlsson, Stefan
    Örebro University, Department of Natural Sciences.
    Mellberg, Karin
    Factors affecting the dissolution of lead pellets in natural watersManuscript (preprint) (Other academic)
  • 50.
    Bäckström, Mattias
    et al.
    Örebro University, Department of Natural Sciences.
    Karlsson, Stefan
    Örebro University, Department of Natural Sciences.
    Salih, Isam
    Pettersson, Håkan
    Chemical character of drinking water from Swedish crystaline bedrockManuscript (preprint) (Other academic)
1234567 1 - 50 of 618
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