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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.

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  • 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, Uppsala, 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, 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.

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  • 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.
    Al Kafri, Yaser
    Örebro University, School of Science and Technology.
    Metals uptake in pine needles  (Pinus nigra)2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
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  • 8.
    Alijagic, Andi
    et al.
    Consiglio Nazionale delle Ricerche, Istituto per la Ricerca e l'Innovazione Biomedica (IRIB), Palermo, Italy.
    Barbero, Francesco
    Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, Barcelona, Spain.
    Gaglio, Daniela
    Consiglio Nazionale delle Ricerche, Istituto di Bioimmagini e Fisiologia Molecolare (IBFM), Segrate, MI, Italy; SYSBIO.IT, Centre of Systems Biology, University of Milano-Bicocca, Milano, Italy.
    Napodano, Elisabetta
    SYSBIO.IT, Centre of Systems Biology, University of Milano-Bicocca, Milano, Italy.
    Benada, Oldřich
    Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic.
    Kofroňová, Olga
    Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic.
    Puntes, Victor F
    Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, Barcelona, Spain; Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain; Vall d Hebron, Institut de Recerca (VHIR), Barcelona, Spain.
    Bastús, Neus G
    Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, Barcelona, Spain.
    Pinsino, Annalisa
    Consiglio Nazionale delle Ricerche, Istituto per la Ricerca e l'Innovazione Biomedica (IRIB), Palermo, Italy.
    Gold nanoparticles coated with polyvinylpyrrolidone and sea urchin extracellular molecules induce transient immune activation2021In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 402, article id 123793Article in journal (Refereed)
    Abstract [en]

    We report that the immunogenicity of colloidal gold nanoparticles coated with polyvinylpyrrolidone (PVP-AuNPs) in a model organism, the sea urchin Paracentrotus lividus, can function as a proxy for humans for in vitro immunological studies. To profile the immune recognition and interaction from exposure to PVP-AuNPs (1 and 10 μg mL-1), we applied an extensive nano-scale approach, including particle physicochemical characterisation involving immunology, cellular biology, and metabolomics. The interaction between PVP-AuNPs and soluble proteins of the sea urchin physiological coelomic fluid (blood equivalent) results in the formation of a protein "corona" surrounding the NPs from three major proteins that influence the hydrodynamic size and colloidal stability of the particle. At the lower concentration of PVP-AuNPs, the P. lividus phagocytes show a broad metabolic plasticity based on the biosynthesis of metabolites mediating inflammation and phagocytosis. At the higher concentration of PVP-AuNPs, phagocytes activate an immunological response involving Toll-like receptor 4 (TLR4) signalling pathway at 24 hours of exposure. These results emphasise that exposure to PVP-AuNPs drives inflammatory signalling by the phagocytes and the resolution at both the low and high concentrations of the PVP-AuNPs and provides more details regarding the immunogenicity of these NPs. 

  • 9.
    Alla, Abdelilah
    et al.
    Departament d'Enginyeria Química, Universitat Politècnica de Catalunya, ETSEIB, Barcelona, Spain.
    Oxelbark, Joachim
    Departament d'Enginyeria Química, Universitat Politècnica de Catalunya, ETSEIB, Barcelona, Spain.
    Rodríguez-Galán, Alfonso
    Departament d'Enginyeria Química, Universitat Politècnica de Catalunya, ETSEIB, Barcelona, Spain.
    Muñoz-Guerra, Sebastián
    Departament d'Enginyeria Química, Universitat Politècnica de Catalunya, ETSEIB, Barcelona, Spain.
    Acylated and hydroxylated polyamides derived from L-tartaric acid2005In: Polymer, ISSN 0032-3861, E-ISSN 1873-2291, Vol. 46, no 9, p. 2854-2861Article in journal (Refereed)
    Abstract [en]

    A series of polyamides 6,4 were prepared from 1,6-hexanediamine and active esters of 2,3-di-O-acylated l-tartaric acid by polycondensation in solution. Both O-alkoyl and O-benzoyl esters were used as hydroxyl protecting groups. The resulting acylated polytartaramides were found to be semicrystalline polymers with Tm between 100 and 200°C and Tg slightly above 100°C. Controlled hydrolysis of the ester side group led to the preparation of poly(hexamethylene l-tartaramide)s with different content in free hydroxyl groups. These polyamides continue being crystalline but their properties largely differ from those displayed by their parent acylated polymers.

  • 10.
    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)
  • 11.
    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)
  • 12.
    Allenmark, Stig
    et al.
    Department of Organic Chemistry, Göteborg University, Göteborg, Sweden.
    Oxelbark, Joakim
    Department of Organic Chemistry, Göteborg University, Göteborg, Sweden.
    Inversion barriers in sulfoxide functions studied by enantioselective liquid chromatography and chiroptical methods1997In: Chirality, ISSN 0899-0042, E-ISSN 1520-636X, Vol. 9, no 5-6, p. 638-642Article in journal (Refereed)
    Abstract [en]

    A series of 2-substituted 1,3,2-benzodithiazole 1-oxides has been synthesized and the compounds resolved into enantiomers by semipreparative enantioselective liquid chromatography. The low enantiomerization barriers have been determined by chiroptical techniques and were found to be relatively independent of the 2-substituent used. The kinetic results are consistent with a pyramidal inversion mechanism and a reduced barrier due to electronic effects, favouring the transition state over the pyramidal ground state. This mechanistic rationale was further supported by data obtained from molecular modelling using AM1 geometry optimization. The absolute configurations have been determined via a comparison of their CD-spectra with those of analogs with previously determined configuration.

  • 13.
    Allenmark, Stig
    et al.
    Department of Organic Chemistry, Göteborg University, Göteborg, Sweden.
    Oxelbark, Joakim
    Department of Organic Chemistry, Göteborg University, Göteborg, Sweden.
    Optically active 1,3,2-benzodithiazole S-oxides: A study of rates of racemization and absolute stereochemistry1996In: Enantiomer (Basel. Print), ISSN 1024-2430, E-ISSN 1607-8446, Vol. 1, no 1, p. 13-22Article in journal (Refereed)
    Abstract [en]

    The optical isomers of the 1-oxide, 1,3-dioxide and 1,1,3-trioxide, respectively, of 2-benzyl-1,3,2-benzodithiazole have been isolated by chiral liquid chromatography. The rate of racemization was found to be much higher for the monooxide as compared to the dioxide or trioxide. A first-order rate constant of 8.65 × 10-5 s-1 was calculated for the racemization of the 1-oxide in acetonitrile at 21°C. This corresponds to rate constants for the forward and reverse reactions in the enantiomerization process of 4.32 × 10-5 s-1 and a Gibbs' free activation energy of only 96.5 kJ mol-1 separating the enantiomers. The absolute configuration at the tricoordinated sulfur atom in the series of oxides was determined via an X-ray crystallographic structure determination of one of the diastereomeric 2-((S)-α-phenyl-ethyl)-1,3,2-benzodithiazole 1,3-dioxides.

  • 14.
    Alm, Therese
    Örebro University, School of Science and Technology.
    Characterization of retention chemicals and their effect on the paper forming process on machine PM4, Billerud Korsnäs Gävle Mill.2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the papermaking industries spots in the finished product is a recurring problem. Billerud Korsnäs have in earlier studies identified poorly optimized retention systems as one of the reasons for these spots. Poorly optimized retention systems will allow for detrimental substances to flow freely in the system, which may cause agglomeration into larger particles that could end up as darker spots in the finished product. The aim of this thesis is to investigate a number of retention systems, consisting of a retention polymer and retention microparticles, and characterize the polymers.The retention aid systems task is to flocculate fibres, fines and fillers along with the colloidal material to improve process parameters. To investigate the retention systems three different retention polymers with different charge densities have been investigated alongside one microparticle. The parameters investigated in this thesis were the retention systems effect on drainage time, turbidity, charge demand and zeta potential. Pulp and white water from PM4 was used to imitate mill conditions.The results showed that the drainage time and turbidity was most effected by the retention aid systems. The polymer with the highest charge yielded the best results. Only minor effects could be detected on charge demand and Zeta potential.

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  • 15.
    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.

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  • 16.
    Alvén Fimmerstad, Tilda
    Örebro University, School of Science and Technology.
    Could fluorinated pharmaceuticals have an impact on the EOF amount in human blood?2022Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Recent studies have discovered an increasing amount of unknown organofluorine in human blood. This increase insinuate that humans might be exposed to potentially new and unidentified organofluorine compounds. Currently there is a large gap between the amount of per- and polyfluorinated substances (PFAS) being monitored and the number of PFAS existing. Due to regulations of legacy PFAS like perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), production have shifted to new PFAS, mainly short-chains (C4-C6). New approaches have been made in order to discover these emerging PFAS, for example total oxidizable precursor (TOP) assay and extractable organofluorine (EOF) analysis. Though, these methods are non-specific and therefore useful in screening of fluorinated compounds. In today’s pharmaceutical market, a lot of drugs contain fluorine, and there is a current increase in number of fluorinated pharmaceuticals. Since EOF analysis measures all organofluorine that can be extracted, the presence of fluorinated pharmaceuticals in a sample may contribute to the EOF amount. However, if fluorinated pharmaceuticals do co-extract during sample preparation for common PFAS analysis is not yet known. This study evaluates if selected pharmaceuticals (fluoxetine, seproxetine, celecoxib and ciprofloxacin) will be co-extracted during ion pair extraction, a common extraction for EOF analysis. The extraction was first optimized in order to gain a good extraction efficiency for the pharmaceuticals. Ion pair solution adjusted to different pH’s (pH 3-4, pH 10 and pH 12) was tested, celecoxib had a good recovery independent of what pH was used (95%-102%), fluoxetine and seproxetine were only extractable at high pH’s (10 and 12) and had a recovery of around 90%, ciprofloxacin, however, could not be extracted no matter a low or high pH. The extraction was then conducted both with a pH of 10 and with a low pH (3-4) on human sera samples (n=6); the sera samples included 3 samples where subjects had been taking fluoxetine and 3 control samples. When analysis of the extracted sera samples was performed, no detectable level of pharmaceutical including its known metabolite seproxetine was found. An EOF and TF analysis of the sera samples were also performed. The EOF analysis could however not indicate any presence of pharmaceutical due to contamination in the procedural blanks. The TF analysis indicated vaguely a higher amount of total fluorine in the sera samples where subjects had taken fluoxetine compared to the control group; however, the large variation between the two groups make it hard to draw any conclusion. Since fluoxetine, seproxetine and celecoxib could be extracted when spike tests were performed, hypothetically they could contribute to the EOF amount. However, since no detectable level was found in the sera samples after extraction it cannot be stated for sure that these pharmaceuticals can be extracted from human blood, using ion-pair extraction. The unanswered question here is if the pharmaceutical is present in some other form in the sera samples, which cannot be extracted, or if it is even present at all.

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  • 17.
    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.

  • 18.
    Amruth, C.
    et al.
    Department of Molecular Physics, Lodz University of Technology, Lodz, Poland.
    Luszczynska, Beata
    Department of Molecular Physics, Lodz University of Technology, Lodz, Poland.
    Szymanski, Marek Zdzislaw
    Örebro University, School of Science and Technology. Department of Engineering and Chemical Sciences, Karlstad University, Karlstad, Sweden.
    Ulanski, Jacek
    Department of Molecular Physics, Lodz University of Technology, Lodz, Poland.
    Albrecht, Ken
    Laboratory for Chemistry and Life Science, Tokyo Institute of Technology, Yokohama, Japan; JST-ERATO Yamamoto Atom Hybrid Project, Tokyo Institute of Technology, Yokohama, Japan; Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka, Japan.
    Yamamoto, Kimihisa
    Laboratory for Chemistry and Life Science, Tokyo Institute of Technology, Yokohama, Japan; Institute for Materials Chemistry and Engineering, Kyushu University, Fukuoka, Japan.
    Inkjet printing of thermally activated delayed fluorescence (TADF) dendrimer for OLEDs applications2019In: Organic electronics, ISSN 1566-1199, E-ISSN 1878-5530, Vol. 74, p. 218-227Article in journal (Refereed)
    Abstract [en]

    This study presents the inkjet printing of a novel OLED device with fully solution-processed organic layers that employ TADF material as an emitting layer. The ink was formulated using new TADF material, triazine core carbazole dendrimers with tert-butyl group at the periphery (tBuG2TAZ), dissolved in a mixture of two non-chlorinated solvents. The influence of the print resolution and the substrate temperature on morphology of the printed films was studied and optimized in ambient conditions. The optimized TADF dendrimer layer was then incorporated in the OLEDs as the emitting layer. The best-printed OLEDs exhibited a maximum current efficiency of 18 cd/A and maximum luminance of 6900 cd/m(2). Such values are comparable to the values obtained in spin coated devices made of the same TADF dendrimer. Further, the mobility of charge carriers extracted from transient electroluminescence measurements of printed OLEDs, when compared to reference OLEDs made by spin coating technique, showed similar values. Finally, we have demonstrated the possibility of patterning of emission the area of complex shapes merely by selectively printing the emission layer. These results demonstrate the potential application of the new dendrimer TADF emitters for the fabrication of efficient OLEDs by an inkjet printing technique.

  • 19.
    Amruth, C
    et al.
    Department of Molecular Physics, Lodz University of Technology, Lodz, Poland.
    Szymański, Marek
    Örebro University, School of Science and Technology. Department of Engineering and Chemical Sciences, Karlstad University, Karlstad, Sweden.
    Łuszczyńska, Beata
    Department of Molecular Physics, Lodz University of Technology, Lodz, Poland.
    Ulański, Jacek
    Department of Molecular Physics, Lodz University of Technology, Lodz, Poland.
    Inkjet Printing of Super Yellow: Ink Formulation, Film Optimization, OLEDs Fabrication, and Transient Electroluminescence2019In: Scientific Reports, E-ISSN 2045-2322, Vol. 9, no 1, article id 8493Article in journal (Refereed)
    Abstract [en]

    Inkjet printing technique allows manufacturing low cost organic light emitting diodes (OLEDs) in ambient conditions. The above approach enables upscaling of the OLEDs fabrication process which, as a result, would become faster than conventionally used vacuum based processing techniques. In this work, we use the inkjet printing technique to investigate the formation of thin active layers of well-known light emitting polymer material: Super Yellow (poly(para-phenylene vinylene) copolymer). We develop the formulation of Super Yellow ink, containing non-chlorinated solvents and allowing stable jetting. Optimization of ink composition and printing resolution were performed, until good quality films suitable for OLEDs were obtained. Fabricated OLEDs have shown a remarkable characteristics of performance, similar to the OLEDs fabricated by means of spin coating technique. We checked that, the values of mobility of the charge carriers in the printed films, measured by transient electroluminescence, are similar to the values of mobility measured in spin coated films. Our contribution provides a complete framework for inkjet printing of high quality Super Yellow films for OLEDs. The description of this method can be used to obtain efficient printed OLEDs both in academic and in industrial settings.

  • 20.
    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, 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.

  • 21.
    Andersson, Marcus
    Örebro University, School of Science and Technology.
    Determination of bio-accessible amounts of metal trace elements in baby food using In vitro artificial digestion2022Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Prefabricated baby food is under strict EU legislation by Commission Regulation (EC) 1881/2006 Setting maximum levels for certain contaminants in foodstuffs regarding the maximum allowed content of potentially harmful elements. For potentially toxic trace elements the regulated maximum content is regulated for lead, cadmium, mercury, inorganic tin, inorganic arsenic, cesium, copper and manganese. The Swedish national food agency (Livsmedelsverket) conducts chemical analyses of the regulated elements by full microwave acid digestion followed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) analysis. In this study a simple artificial in vitro digestion method was developed using a commercially available enzyme supplement and optimized to determine the bio-accessible amount of eight potentially harmful metal trace elements that are associated with modern electronics (lithium, vanadium, cobalt, nickel, arsenic, selenium, cadmium and lead) in five prefabricated baby meals from the Swedish market by well-established manufacturers. The results were compared to the total mass content as well as the regulated limits and toxicological literature data. The samples had analyte dry mass contents that were extractable by the developed in vitro method that ranged from 0.0314 μg g-1 to 0.0691 μg g-1 for lithium, 9.42*10-5 μg g-1 to 0.0152 μg g-1 for vanadium, 6.61*10-3 μg g-1 to 30.9*10-3 μg g-1 for cobalt, 0.0599 μg g-1 to 0.194 μg g-1 for nickel, 4.54*10-4 μg g-1 to 0.0431 μg g-1 for arsenic, 8.87*10-4 μg g-1 to 9.85*10-3 μg g-1 for cadmium and 1.24*10-3 μg g-1 to 0.0232 μg g-1 for lead. Selenium was not detected in any of the samples. None of the samples were found to contain toxic levels of any of the quantified elements. Comparisons and paired t-tests of recoveries between the in vitro digestion and control procedures consisting of digestion solutions that exclude either enzymes, pH adjustment or both suggested that lithium, cobalt and cadmium were protein bound and that the digestion enzymes used had a statistically significant effected on the recovery. With further optimization and more extensive comparison to reference data the method could potentially be established as a simple and affordable alternative to more elaborate methods for screening or small scale analysis of the bio-accessible fraction of metal trace elements in food.

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  • 22.
    Andersson Ohnback, Chris
    Örebro University, School of Science and Technology.
    Evaluation of an accelerated solvent extraction method for screening of polybrominated diphenyl ethers and emerging flame retardants in pilot whales (Globicephala melas).2021Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    There is a need to increase the ability to extract a wider range of chemicals in for examplebiological or human samples to monitor environmental pollutants of both current andfuture concern. Flame retardants are commonly used in society but are also environmentalpollutants due to their persistence, toxicity, and mobility in nature. Six different methodsbased on accelerated solvent extraction (ASE) with two different cleanup steps wereevaluated and compared to an open column extraction and multilayer silica cleanup for theanalysis of polybrominated diphenyl ethers (PBDEs), tetrabromobisphenol A (TBBPA),hexabromocyclododecane (HBCDD) and some selected organophosphate flame retardants(OPFRs) in whale blubber. The solvents evaluated were toluene, acetone, anddichloromethane, and the cleanup methods were deactivated silica and Florisil. Thecompounds were analyzed using a gas chromatograph coupled with an Orbitrap massspectrometer (GC/MS-Orbitrap) operated in electron ionization (EI) mode. The methodswere evaluated based on their precision, accuracy, and inclusivity of selected targetcompounds. There was no single method that could replace the original in terms ofperformance for all PBDEs and at the same time also include OPFRs, HBCDD, andTBBPA. All target compounds were detected in whale samples from Faroe Island, but thelimit of detection (LOD) varied depending on the method used. If the evaluation was to berepeated, then a sequential ASE using multiple solvents would possibly be a suitablemethod for including a wide range of compounds with retained precision and accuracy forPBDEs.

  • 23.
    Andrén, Daniel
    et al.
    Department of Physics, Chalmers University of Technology, Göteborg, Sweden.
    Länk, Nils Odebo
    Department of Physics, Chalmers University of Technology, Göteborg, Sweden.
    Sípová-Jungová, Hana
    Department of Physics, Chalmers University of Technology, Göteborg, Sweden.
    Jones, Steven
    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.
    Surface Interactions of Gold Nanoparticles Optically Trapped against an Interface2019In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 123, no 26, p. 16406-16414Article in journal (Refereed)
    Abstract [en]

    Particles that diffuse in close proximity to a surface are expected to behave differently than in free solution because the surface interaction will influence a number of physical properties, including the hydrodynamic, optical, and thermal characteristics of the particle. Understanding the influence of such effects is particularly important in view of the increasing interest in laser tweezing of colloidal resonant nanoparticles for applications such as nanomotors and optical printing and for investigations of unconventional optical forces. Therefore, we used total internal reflection microscopy to probe the interaction between a glass surface and individual similar to 100 nm gold nanoparticles trapped by laser tweezers. The results show that particles can be optically confined at controllable distances ranging between similar to 30 and similar to 90 nm from the surface, depending on the radiation pressure of the trapping laser and the ionic screening of the surrounding liquid. Moreover, the full particle-surface distance probability distribution can be obtained for single nanoparticles by analyzing temporal signal fluctuations. The experimental results are in excellent agreement with Brownian dynamics simulations that take the full force field and photothermal heating into account. At the observed particle-surface distances, translational friction coefficients increase by up to 60% compared to freely diffusing particles, whereas the rotational friction and thermal dissipation are much less affected. The methodology used here is general and can be adapted to a range of single nanoparticle-surface interaction investigations.

  • 24.
    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.

  • 25.
    Aro, Rudolf
    Örebro University, School of Science and Technology.
    Organofluorine Mass Balance and Per- and Polyfluoroalkyl Substance Analysis of Environmental Samples and Human Blood2021Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Per- and polyfluoroalkyl substances (PFAS) have been linked to a range of negative health and environmental effects. Regulations limiting and/or banning the use of some of the legacy compounds have been introduced. Consequently, the production and use of PFAS has diversified. The risks posed by these newly introduced PFAS to both the environment and humans may be underestimated if they are not evaluated in current monitoring programs. Organofluorine mass balance analysis has been used in previous studies to estimate the overall exposure to PFAS since naturally occurring organofluorine compounds are rare in nature.

    In this thesis, the organofluorine mass balance analysis was performed on a variety of samples, from surface water to sewage and human blood. The results indicated the ubiquitous presence of unidentified organofluorines in all environmental compartments and human samples, for example, more than 50 % of extractable organofluorine (EOF) in human samples could not be accounted for by an extended list of target analytes. Until these compounds are identified, it is not possible to assess the risks they pose and it could lead to misguided policy decisions.

    To tackle the increasingly complex analytical picture and ensure more comprehensive screening, a workflow using EOF as an initial metric to identify pollution hot-spots was proposed. The wider adoption of organofluorine mass balance analysis would also require a better understanding of the analytical instrumentation used for this type of work. Experiments carried out here demonstrated the robustness of combustion ion chromatography in EOF analysis and highlighted areas in need of improvement.

    While organofluorine mass balance analysis has its drawbacks, the potential health and environmental risks posed by the unidentified organofluorine compounds cannot be underestimated.

    List of papers
    1. Fluorine Mass Balance Analysis of Effluent and Sludge from Nordic Countries
    Open this publication in new window or tab >>Fluorine Mass Balance Analysis of Effluent and Sludge from Nordic Countries
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    2021 (English)In: ACS - ES & T Water, E-ISSN 2690-0637, Vol. 1, no 9, p. 2087-2096Article in journal (Refereed) Published
    Abstract [en]

    Recent publications have highlighted the ubiquitous presence of unidentified organofluorine compounds, whose environmental occurrence is poorly understood. In this study, wastewater treatment plant (WWTP) effluent and sludge samples from seven countries were analyzed for extractable organofluorine (EOF) and target PFAS, to evaluate which compounds are released back into the environment. Fluorine mass balance analysis of effluent samples (n = 14) revealed that on average 90% of the EOF could not be explained by the 73 PFAS monitored in this investigation. The levels of EOF in effluent (324–1460 ng of F/L) and sludge (39–210 ng of F/g of dry weight) indicate that a substantial amount of organofluorine compounds is released back into nature. A commonly overlooked PFAS class, ultra-short-chain PFCAs, accounted for 4% of EOF on average, while the remaining 71 compounds explained only a further 6% of EOF on average. The highest number of PFAS was detected in the effluent dissolved phase (37), compared to 29 and 23 PFAS in sludge and effluent particulate phase, respectively. The increased concentrations of EOF in both WWTP effluent and sludge are of concern, as the chemical species contained therein remain largely unknown, and thus, their potential health and environmental risks cannot be assessed.

    Place, publisher, year, edition, pages
    American Chemical Society (ACS), 2021
    Keywords
    Fluorine, mass balance analysis, per- and polyfluorinated substances, sludge, effluent, extractable organofluorine
    National Category
    Environmental Sciences
    Identifiers
    urn:nbn:se:oru:diva-94035 (URN)10.1021/acsestwater.1c00168 (DOI)000696179500011 ()2-s2.0-85120567139 (Scopus ID)
    Funder
    Swedish Research Council Formas, 2016-01158Knowledge Foundation
    Note

    Funding agencies:

    Nordic Chemical Group

    Enforce Research Profile, Sweden 20160019

    Available from: 2021-09-01 Created: 2021-09-01 Last updated: 2024-02-05Bibliographically approved
    2. Fluorine mass balance analysis of selected environmental samples from Norway
    Open this publication in new window or tab >>Fluorine mass balance analysis of selected environmental samples from Norway
    Show others...
    2021 (English)In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 283, article id 131200Article in journal (Refereed) Published
    Abstract [en]

    The presence of unidentified organofluorine compounds (UOF) has been investigated in recent publication, but their environmental occurrence is still poorly understood. Fluorine mass balance analysis was performed on environmental samples from lake Mjøsa and river Alna (surface water (n = 9), sediment (n = 5) and fish liver (n = 4)) and sewage samples from Oslo (n = 5), to reveal to the fraction of UOF. In samples that had extractable organofluorine (EOF) concentrations above the limit of detection (LoD), more than 70% of their EOF could not be accounted for by the 37 PFAS monitored in this study. The surface water samples from lake Mjøsa had EOF concentrations several times higher than what has been reported elsewhere in Nordic nations. The flux of EOF in river Alna and selected sewage pipes revealed that it was 1-2 orders of magnitude higher than the flux of the measured PFAS. The elevated concentrations of EOF in all samples pose a potential health and environmental hazard, as their composition remains mostly unknown.

    Place, publisher, year, edition, pages
    Pergamon Press, 2021
    Keywords
    Fluorine mass balance analysis per- and polyfluorinated substances extractable organofluorine surface water passive sampler sediment
    National Category
    Environmental Sciences
    Identifiers
    urn:nbn:se:oru:diva-92560 (URN)10.1016/j.chemosphere.2021.131200 (DOI)000692107900011 ()34157625 (PubMedID)2-s2.0-85109094064 (Scopus ID)
    Funder
    Swedish Research Council Formas, 2016-01158Knowledge Foundation, 20160019
    Note

    Funding agency:

    Norwegian Environment Agency

    Available from: 2021-06-23 Created: 2021-06-23 Last updated: 2022-02-03Bibliographically approved
    3. Organofluorine Mass Balance Analysis of Whole Blood Samples in Relation to Gender and Age
    Open this publication in new window or tab >>Organofluorine Mass Balance Analysis of Whole Blood Samples in Relation to Gender and Age
    (English)Manuscript (preprint) (Other academic)
    National Category
    Other Chemistry Topics
    Identifiers
    urn:nbn:se:oru:diva-94037 (URN)
    Available from: 2021-09-01 Created: 2021-09-01 Last updated: 2024-01-16Bibliographically approved
    4. Extractable Organofluorine Analysis: a Way to Screen for Elevated Per- and Polyfluoroalkyl Substance Contamination in Humans?
    Open this publication in new window or tab >>Extractable Organofluorine Analysis: a Way to Screen for Elevated Per- and Polyfluoroalkyl Substance Contamination in Humans?
    Show others...
    (English)Manuscript (preprint) (Other academic)
    National Category
    Other Chemistry Topics
    Identifiers
    urn:nbn:se:oru:diva-94039 (URN)
    Available from: 2021-09-01 Created: 2021-09-01 Last updated: 2024-01-16Bibliographically approved
    5. Combustion Ion Chromatography for Extractable Organofluorine Analysis
    Open this publication in new window or tab >>Combustion Ion Chromatography for Extractable Organofluorine Analysis
    Show others...
    (English)Manuscript (preprint) (Other academic)
    National Category
    Other Chemistry Topics
    Identifiers
    urn:nbn:se:oru:diva-94041 (URN)
    Available from: 2021-09-01 Created: 2021-09-01 Last updated: 2024-01-16Bibliographically approved
    6. Towards a comprehensive analytical workflow for the chemical characterisation of organofluorine in consumer products and environmental samples
    Open this publication in new window or tab >>Towards a comprehensive analytical workflow for the chemical characterisation of organofluorine in consumer products and environmental samples
    2020 (English)In: TrAC. Trends in analytical chemistry, ISSN 0165-9936, E-ISSN 1879-3142, Vol. 123, article id 115423Article, review/survey (Refereed) Published
    Abstract [en]

    This review summarizes and discusses eight analytical methods for organofluorine (OF) analysis, which offer detection limits suitable for consumer products and environmental samples. Direct sample analysis of OF only applies to some techniques on consumer products, whereas others require sample pretreatment or concentration before measurements. Comparison between methods for OF analysis were found to be difficult because of different selectivity (between OF and fluoride), sensitivity and type of samples (bulk, extract, surface) analysed. Neither inter-laboratory comparison on OF analysis nor suitable certified reference materials have been used for method validation, which makes data comparability between studies challenging. A top down approach for the comprehensive assessment of OF is proposed, where OF/extractable OF is first measured, followed by target analysis to obtain unquantifiable OF concentrations using the mass balance approach. For further identification of unquantifiable OF, approaches such as total oxidizable precursor assay, suspect and non-target screening are briefly discussed.

    Place, publisher, year, edition, pages
    Elsevier, 2020
    Keywords
    Fluorine mass balance, Extractable organofluorine (EOF), Per- and polyfluoroalkyl substances (PFASs), Combustion ion chromatography (CIC), Particle-induced gamma-ray emission spectrometry (PIGE), Inductively coupled plasma MS/MS (ICP-MS/MS)
    National Category
    Analytical Chemistry
    Identifiers
    urn:nbn:se:oru:diva-80250 (URN)10.1016/j.trac.2019.02.024 (DOI)000512979800001 ()2-s2.0-85062809595 (Scopus ID)
    Funder
    Swedish Research Council, 2015-00320Swedish Research Council Formas, 2016-01158Knowledge Foundation, 20160019
    Available from: 2020-02-28 Created: 2020-02-28 Last updated: 2021-09-01Bibliographically approved
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    Organofluorine Mass Balance and Per- and Polyfluoroalkyl Substance Analysis of Environmental Samples and Human Blood
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  • 26.
    Aro, Rudolf
    et al.
    Örebro University, School of Science and Technology.
    Ben Ayoub, Mohamed Wajdi
    CETIAT, Villeurbanne, France; Aix Marseille University, CNRS, Marseille Centrale, Institut Fresnel UMR 7249, Marseille, France.
    Leito, Ivo
    Institute of Chemistry, University of Tartu, Tartu, Estonia.
    Georgin, Eric
    CETIAT, Villeurbanne, France.
    Savanier, Benoit
    CETIAT, Villeurbanne, France.
    Calibration and Uncertainty Estimation for Water Content Measurement in Solids2021In: International journal of thermophysics, ISSN 0195-928X, E-ISSN 1572-9567, Vol. 42, no 3, article id 42Article in journal (Refereed)
    Abstract [en]

    In the field of water content measurement, the calibration of coulometric methods (e.g., coulometric Karl Fischer titration or evolved water vapor analysis) is often overlooked. However, as coulometric water content measurement methods are used to calibrate secondary methods, their results must be obtained with the highest degree of confidence. The utility of calibrating such instruments has been recently demonstrated. Both single and multiple point calibration methods have been suggested. This work compares these calibration methods for the evolved water vapor analysis technique. Two uncertainty estimation approaches (Kragten's spreadsheet and M-CARE software tool) were compared as well, both based on the ISO GUM method.

  • 27.
    Aro, Rudolf
    et al.
    Örebro University, School of Science and Technology.
    Eriksson, Ulrika
    Örebro University, School of Science and Technology.
    Kärrman, Anna
    Örebro University, School of Science and Technology.
    Jakobsson, Kristina
    School of Public Health and Community Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden.
    Yeung, Leo W. Y.
    Örebro University, School of Science and Technology.
    Extractable Organofluorine Analysis: a Way to Screen for Elevated Per- and Polyfluoroalkyl Substance Contamination in Humans?Manuscript (preprint) (Other academic)
  • 28.
    Aro, Rudolf
    et al.
    Örebro University, School of Science and Technology.
    Eriksson, Ulrika
    Örebro University, School of Science and Technology.
    Kärrman, Anna
    Örebro University, School of Science and Technology.
    Reber, Iris
    Metrohm AG, Ionenstrasse, Herisau, Switzerland.
    Yeung, Leo W. Y.
    Örebro University, School of Science and Technology.
    Combustion Ion Chromatography for Extractable Organofluorine AnalysisManuscript (preprint) (Other academic)
  • 29.
    Aro, Rudolf
    et al.
    Örebro University, School of Science and Technology.
    Eriksson, Ulrika
    Örebro University, School of Science and Technology.
    Kärrman, Anna
    Örebro University, School of Science and Technology.
    Yeung, Leo W. Y.
    Örebro University, School of Science and Technology.
    Organofluorine Mass Balance Analysis of Whole Blood Samples in Relation to Gender and AgeManuscript (preprint) (Other academic)
  • 30.
    Aro, Rudolf
    et al.
    University of Tartu, Institute of Chemistry, Tartu, Estonia; CETIAT, 25 Avenues of the Arts, Villeurbanne, France; Université Claude Bernard Lyon, Villeurbanne, France.
    Wajdi Ben Ayoub, Mohamed
    CETIAT, 25 Avenues of the Arts, Villeurbanne, France; CNRS, Marseille Centrale, Institut Fresnel, Aix Marseille University, Marseille, France.
    Leito, Ivo
    University of Tartu, Institute of Chemistry, Tartu, Estonia.
    Georgin, Éric
    CETIAT, 25 Avenues of the Arts, Villeurbanne, France.
    Moisture in Solids: Comparison Between Evolved Water Vapor and Vaporization Coulometric Karl Fischer Methods2020In: International journal of thermophysics, ISSN 0195-928X, E-ISSN 1572-9567, Vol. 41, no 8, article id 113Article in journal (Refereed)
    Abstract [en]

    Moisture content can affect the thermo-physical properties of many materials. Thus sufficient knowledge of this parameter is required to improve product shelf life and quality, reduce waste or enhance process efficiency. The traditional loss on drying methods are still the go-to methods due to their robustness and simplicity. However, their inherent lack of selectivity imposes restrictions. These are overcome with newer techniques such as vaporization coulometric Karl Fischer titration (vap-C-KFT) and evolved water vapor analysis (EWV). The former is a well-established method, but the latter was more recently introduced and the literature available on it is scarce. This work aims to bridge this gap in knowledge and demonstrate the comparability of the EWV to the more established vap-C-KFT. Multiple samples were studied and the data are analyzed along the principles reported recently by INRiM with a few modifications.

  • 31.
    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.

  • 32.
    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.

  • 33.
    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: Programme and Abstracts: 25th International Applied Geochemistry Symposium, 22-26 August, 2011, Rovaniemi, Finland / [ed] Pertti Sarala, V. Juhani Ojala, Marja-Leena Porsanger, Vuorimiesyhdistys - Finnish Association of Mining and Metallurgical Engineers , 2011, p. 77-77Conference paper (Refereed)
  • 34.
    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.

  • 35.
    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.

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    Characterization of the metabolic changes in chicken liver due to
  • 36.
    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.

  • 37.
    Ax, Erika
    et al.
    Uppsala Univeristy, Uppsala, Sweden.
    Salihovic, Samira
    Örebro University, School of Science and Technology.
    Lind, P. Monica
    Occupational & Environmental Medicine, Uppsala University, Uppsala, Sweden.
    van Bavel, Bert
    Örebro University, School of Science and Technology.
    Lind, Lars
    Acute & Internal Medicine, Uppsala University, Uppsala, Sweden.
    Lampa, Erik
    Occupational & Environmental Medicine, Uppsala University, Uppsala, Sweden.
    Sjögren, Per
    Clinical Nutrition & Metabolism, Uppsala University, Uppsala, 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)
  • 38. 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)
  • 39.
    Ayoub, M. W. Ben
    et al.
    CETIAT, Villeurbanne, France; Aix Marseille Univ, Marseille, France.
    Georgin, Éric
    CETIAT, Villeurbanne, France.
    Rochas, Jean François
    CETIAT, Villeurbanne, France.
    Hubert, S.
    CETIAT, Villeurbanne, France.
    Aro, Rudolf
    CETIAT, Villeurbanne, France.
    Neves, Luisa
    Aix Marseille Univ, Marseille, France; Centre Commun de Ressources en Micro-ondes (CCRM), Marseille, France.
    Sabouroux, Pierre
    Aix Marseille Univ, Marseille, France.
    Quantitative determination of bound water in cardboard by measurement of dielectric permittivity2018In: Measurement science and technology, ISSN 0957-0233, E-ISSN 1361-6501, Vol. 29, no 2, article id 024001Article in journal (Refereed)
    Abstract [en]

    In this study we investigated the complex dielectric permittivity of cardboard with different water contents using a coaxial transmission/reflection technique from 10 MHz to 1.5 GHz. A relaxation process was analyzed to identify the bonding forms that exist in cardboard; this analysis was accompanied by a selective direct thermo-coulometric method. Two different types of bonding of water are found in cardboard (free and bound water) and both can be eliminated at 105 degrees C. The novelty of this work is the experimental correlation between the relaxation frequency situated in the radio-frequency band and the fraction of bound water in cardboard with a low water content.

  • 40.
    Ayranci Dahlberg, Rebecka
    Örebro University, School of Science and Technology.
    Remediation of per- and polyfluoroalkyl substances (PFAS) in contaminated water by sorption to pine- and spruce bark2023Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    PFAS are anthropogenic substances used in many different industrial operations and products because of their unique properties. Due to their negative impact on human health and environmental bioaccumulative characteristics different authorities have addressed the issue. In Sweden the limit is4 ng/L for four different PFAS in drinking water. Another risk to human health is elevated concentrations of toxic elements, causing Sweden to include them in the drinking water regulations withlimits such as 5 µg/L for arsenic, 25 µg/L for chromium and 5 µg/L for lead.This study is a continuation of an investigation for PFAS remediation in contaminated water by sorption to pine and spruce bark. The earlier study was a laboratory scale and implied that pine and spruce have some sorption capacity for long-chain PFAS. In this study pine and spruce bark were used as sorbent at an industrial site. The analysis was performed by weak-anion exchange extraction followed bysupercritical fluid chromatography coupled with a tandem mass spectrometer (SFC-MS/MS) and liquid chromatography coupled with tandem mass spectrometer (LC-MS/MS) for instrumental analyses of target ultra-short-chain PFAS, short- and long chain PFAS and branched PFOS isomers. An elemental analysis was executed with inductively coupled plasma mass spectrometry. The obtained results indicated removal for certain long-chain PFAS, potential for sorption of a specific ultra-short-chain PFAS and the elemental analysis implied some reduction of the chromium concentrations. 

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  • 41.
    Baabish, Abeer
    Örebro University, School of Science and Technology.
    Global Priority Perfluoroalkyl Substances in Surface Waters:Establishing Baseline Levels on Regional Basis.2019Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Perfluorooctane sulfonic acid (PFOS) has been regulated under Stockholm Convention in 2009, perfluorooctanoic acid (PFOA) was listed in 2019. Perfluorohexane sulfonic acid (PFHxS) is under review and could be included in 2021. There are still permitted uses of these three chemicals, but it is expected that the production and application will decrease as a result of the international regulation and the environmental concentrations of PFOS, PFOA and PFHxS are expected to decline. However, without a reference point, it is difficult to judge if the levels are decreasing or not. Therefore, baseline levels of PFOS, PFOA and PFHxS in one of United Nations Environment Programme (UNEP) core matrices, surface water, were established with the support of samples collected from Africa (n=34), Asia (n=11), Group of Latin America and Caribbean (GRULAC) (n=35) and Pacific Islands (n=25) under a period of two years. The baseline levels were set as the median concentration (ng/L) in each region (interquartile range) based on a variance test (Kruskal-Wallis) and descriptive statistical testing.

    Baseline levels for ΣPFOS, PFOA and PFHxS including all countries in Africa (n=6) was set at 0.38 (0.18 – 0.54) ng/L, 0.26 (0.13 – 0.80) ng/L and 0.042 (0.02 - 0.09) ng/L respectively, and excluding Kenya and Tunisia (n=4) at 0.22 (0.10 – 0.38) ng/L for ΣPFOS , 0.18 (0.10 – 0.25) ng/L for PFOA and 0.031 (0.02 – 0.04) ng/L for PFHxS.

    In Pacific Islands the baseline levels for ΣPFOS, PFOA and PFHxS were established at 0.15 (0.04 – 1.24) ng/L, 0.046 (0.03 – 0.11) ng/L and 0.055 (0.01 – 0.63) ng/L including all countries (n=7), and 0.053 (0.03 – 0.15) ng/L, 0.033 (0.03 – 0.04) ng/L and 0.012 (0.01 – 0.05) ng/L excluding Vanuatu and Kiribati (n=5).

    In Asia and Group of Latin America samples were in similar concentrations range within the region, so baseline levels for ΣPFOS, PFOA and PFHxS in Asia were set at 0.048 (0.04 - 0.12) ng/L, 0.11 (0.07 – 0.19) ng/L and 0.018 (0.01-0.03) ng/L, and in GRULAC at 1.31(0.39 – 1.88) ng/L, 0.50 (0.28 – 0.71) ng/L and 0.14 (0.06 – 0.44) ng/L for the three priority PFASs respectively.

    The importance of the three PFASs in relation to other measured Σ73 PFASs were assessed in selected samples (n=12) including six samples from Sweden. The results showed a contribution of 10% to 48% of the sum of the three priority PFASs to all 27 detected PFASs.It is not clear whether a total of 73 PFASs is enough to explain the environmental contamination of PFASs and therefore the extractable organofluorine (EOF) was measured in selected samples (n=12). Due to the high EOF levels in procedural blanks, only two out of twelve samples were used to assess the contribution of detected PFASs to EOF. The contribution of 27 detected PFASs to EOF were 3% for Vanuatu and 5% for Sweden (Svartån). The contribution of the sum of the three PFASs to EOF accounted for 1.1% for Vanuatu and 1.4% for Svartån. Nevertheless, within the organofluorine fraction, a major percentage 95% to 97% of fluorine remains unknown in water samples, suggesting the occurrence of other organofluorine substances.

    At the same time, some newly identified PFAS (novel PFASs) that are known to replace PFOS and PFOA in different applications were detected in surface water samples collected from Sweden (n=6) and from developing countries under UNEP/GMP2 project (n=6). Perfluoroethylcyclohexane sulfonate (PFECHS) was detected in four samples in concentrations ranging between 0.03 and 0.14 ng/L. Perfluoro-2-propoxypropanoic acid (HFPO-DA) was detected in three samples in the concentration range 0.03-0.06 ng/L.

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    Global Priority Perfluoroalkyl Substances in Surface Waters: Establishing Baseline Levels on Regional Basis.
  • 42.
    Bartuma, Ninorta
    Örebro University, School of Science and Technology.
    Optimizing purification of oligonucleotides with reversed phase trityl-on solid phase extraction2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Oligonucleotides are synthetic strings of DNA or RNA used mostly for biochemical analysis and diagnostics. For them to be useful in these fields, a purity over 90% is most often required. However, when synthesizing these sequences, many “failures” (shorter sequences) are made in the step-wise process. The synthesized oligonucleotides need to therefore be purified. This is most often done with gel electrophoresis or liquid chromatography. These methods are, on the other hand, very time-consuming and laborious. Solid phase extraction (SPE) is a much faster purification method if optimized and it can be done with the standard cartridges as well as 96-well plates, that allow many samples to efficiently be run at the same time. With reversed phase (RP) SPE, the dimethoxytrityl (DMT) group, that is attached to the target at the final synthesis step, can be used for stronger retention to the bed sorbent and leaving only the target at the final eluting stage. The impurities without a DMT-on group, that do not adsorb to the sorbent, are washed away in earlier steps. The purpose of this study is to optimize an SPE method for purification of oligonucleotides. Two different cartridges, Clarity QSP (Phenomenex) and Glen-Pak (Glen Research) were used. The purity analysis and oligonucleotide identification were done using anion exchange - high performance liquid chromatography (AIE-HPLC) and time-of-flight mass spectrometry (TOF MS).

    To conclude, Clarity QSP achieved, at the most, a purity of 68.8% with the recommended SPE steps by Phenomenex. Alterations in the extraction procedure resulted in similar purity or lower. Glen-Pak reached a peak purity of 78.8% when doing a double salt wash of 5% ACN in 2 M sodium chloride and another double wash after detritylation with 1% acetonitrile. This method has to be further optimized in order to reach a purity of at least 90% to be useful in industrial settings.

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    Optimizing purification of oligonucleotides with reversed phase trityl-on solid phase extraction
  • 43.
    Begic, Elvira
    Örebro University, School of Science and Technology.
    Combined analysis of PFAS and bile acids in human blood using UPLC-MS/MS2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A method was performed to enable a combined analysis for quantifying levels of perfluoroalkyl substances (PFAS) and bile acids in human plasma samples from Taiwan. Protein precipitation and phospholipid removal was performed using a 96-well plate and analysed with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MSMS). The instrumental analysis was performed with a reverse-phased chromatography. The mass analysis was carried out using multiple reaction monitoring (MRM) mode. A matrix matched calibration curve using new-born bovine serum (NBS) was used for the analysis of the PFAS and an external one point calibration for the bile acids. The twenty plasma samples were collected after an over-night fast and consisted of seventeen samples from patients undergoing haemodialysis and three samples from healthy controls. The variation between the healthy controls and the patient samples is observed where a higher concentration of L-PFOS, PFOA, PFNA and PFHxS was found in the control samples. It is explained that haemodialysis can decrease the amount of PFOS. The lower concentrations found in the human plasma was of PFHpA. 18 of 30 bile acids were detected but eight of them were selected for quantitative analysis. The concentration of the bile acids varied less between the three control samples and the seventeen patient samples when compared to the PFAS. The highest median value was found for CDCA whilst GHCA had the lowest median value. Taken together, the combined analysis of bile acids and PFAS was accomplished along with the determination of their concentration in human plasma.

  • 44.
    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.

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  • 45.
    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.

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  • 46.
    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.

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    Trophic transfer of per- and polyfluoroalkyl substances (PFASs) by glacial relicts in Lake Vättern, Sweden
  • 47.
    Bergqvist, Sandra
    Örebro University, School of Science and Technology.
    Content determination of explosive precursors and narcotic salts using 35Cl-nuclear magnetic resonance2023Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Explosive precursors and narcotic salts are chemicals contributing to an undesirabledevelopment of the Swedish society, both in terms of criminal activities and harm to the environment. Reducing the illegal use of these chemicals is important in the work towards a safer society. National Forensic Centre (NFC) is the state agency responsible for forensic investigations for the Swedish Police Authority. The Drug Analysis and ChemistryTechnology section at NFC were both in need for an accurate quantification method to determine the content of Cl in narcotic salts and explosive precursors. Nuclear magnetic resonance (NMR) spectroscopy was assessed to be suitable since a recently published article had shown applicability of 35Cl NMR on narcotic salts. The aim of the method was to find the most appropriate parameter settings for the compounds of interest, including operating frequency, 90° pulse length, number of scans, relaxation time, and relaxation delay. To ensure a reliable and accurate method, the following validation parameters were studied; linearity, limit of detection (LOD), limit of quantification (LOQ), intermediate precision, trueness, repeatability, and ruggedness. Dimethyl sulfoxide (d6-DMSO) was chosen as the preferredsolvent for the Drug Analysis section since it is a common solvent for their 1H-NMR analysis. For explosive precursors results showed advantages of using deuterium oxide (D!O) as solvent, considering accuracy, solubility and shorter analysis time.Concluding, the chosen criteria of signal-to-noise (S/N) ratio >6 resulted in an LOQ of around 0.15g/L, though this was dependent upon the number of scans utilized. Successful pulse length experiments determined exact 90° pulse lengths for each sample and solvent combination. The longitudinal relaxation time T1 was also successfully determined, and since it was multiplied with five to ensure complete relaxation to stable state the relaxation delay D1was assumed as an insignificant parameter for the determination of chloride. Quantification was based upon the pulse-length based concentration determination (PULCON) using an external standard. The ruggedness can be studied additionally by another experienced operator (since trueness was strongly dependent upon the preparation of the external standard solution). The method displayed good linearity over the mass range normally utilized in such quantifications. The conclusion drawn in the thesis is that the method shows great promise but additional analyzes are still required before implementation at NFC

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    fulltext
  • 48.
    Bernheim, Fredrik
    Örebro University, School of Science and Technology.
    Fluoride removal by low-cost adsorbents2022Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Fluoride, the most abundant form of fluorine, is an ion released into the environment, mainly via anthropogenic sources and erosion of mineral rocks. Although the element is well known for its health benefits on teeth and bones, it can as well be a harmful pollutant. In some areas on earth, the population can not obtain drinking water that is below the guideline limits of fluoride, which is set to 1.5 mg/L by the world health organization (WHO). Therefore there is a relevance to develop methods that can clean the waters from excess fluoride. The potential problems when it comes to finding these types of methods is that they can be expensive. However, materials generated as residues in industrial processes may be low in cost. In this thesis, silicon reduced AOD-slag, a material generated as a by-product from the production of stainless steel, was examined by its fluoride adsorption behavior and adsorption capacity. The concentrations of fluoride were measured with ion chromatography (IC) and the concentration of metals were analyzed with microwave plasma atomic emission spectroscopy (MP-AES). Additionally pH and conductivity were measured. The functionality of the material surface was analyzed with isotherm modeling, where the Sips isotherm model was tested. Moreover, optimization of the slag was performed by heat treating the material, as well as a sorption kinetics test on both optimized and original slags. The results from the analysis indicated that the material corresponds well to the Sips isotherm. Considering this result it is suggested that at low concentrations, the surface can be characterized as heterogeneous, with different binding energies at different available sites. At higher concentrations the Sips-model explains the surface to be saturated when a monolayer of fluoride is formed. Therefore the binding on the slag surface can be described to have an inner-sphere and covalent character. The metal analysis showed that calcium ions are released from the slag when in aqueous solutions. The presence of calcium in the liquid samples are believed to result in formations of solid calcium fluoride (CaF2), precipitated on the slag surface. Lastly, the maximum fluoride removal is believed to differ between different types of AOD-slag, where there as well are possibilities to optimize the material.

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    fulltext
  • 49.
    Biswas, Dipsikha
    et al.
    Dalhousie Med New Brunswick, St John, NB, Canada.
    Cowie, Andrew
    Dalhousie Med New Brunswick, St John, NB, Canada.
    Tozer, Kathleen
    Dalhousie Med New Brunswick, St John, NB, Canada.
    Perez, Lester J.
    Dalhousie Med New Brunswick, St John, NB, Canada.
    Trivedi, Purvi
    Dalhousie Med New Brunswick, St John, NB, Canada.
    Bartlett, Jordan J.
    Dalhousie Med New Brunswick, St John, NB, Canada.
    Duffley, Luke
    Univ New Brunswick, St John, NB, Canada.
    Dao, Khoi Thien
    Univ New Brunswick, St John, NB, Canada.
    Paramel Varghese, Geena
    Dalhousie Med New Brunswick, St John, NB, Canada..
    Aguiar, Christie
    St Johns Hosp, St John, NB, Canada.
    Yip, Alexandra M.
    St Johns Hosp, St John, NB, Canada.
    Shea, Jennifer
    St Johns Hosp, St John, NB, Canada.
    Brunt, Keith
    Dalhousie Med New Brunswick, St John, NB, Canada.
    Legare, Jean-Francois
    St Johns Hosp, St John, NB, Canada.
    Hassan, Ansar
    St Johns Hosp, St John, NB, Canada.
    Kienesberger, Petra
    Dalhousie Med New Brunswick, St John, NB, Canada.
    Pulinilkunnil, Thomas
    Dalhousie Med New Brunswick, St John, NB, Canada.
    Adverse Cardiometabolic Outcomes in Obese Patients Correlates Strongly with Defective Branched-Chain Amino Acid Catabolism2018In: Journal of Molecular and Cellular Cardiology, ISSN 0022-2828, E-ISSN 1095-8584, Vol. 124, p. 121-122Article in journal (Other academic)
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    sammanfattning
  • 50.
    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: 2022-02-03Bibliographically 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: 2018-08-16Bibliographically 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: 2018-08-16Bibliographically 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
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    Polybrominated dibenzo-p-dioxins and furans: from source of emission to human exposure
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