Search for dissertations about: "Mercury methylation"

Showing result 1 - 5 of 12 swedish dissertations containing the words Mercury methylation.

  2. 1. Remediation of mercury contaminated soil and biological mercury methylation in the landscape

    Author : Jingying Xu; Stefan Bertilsson; Andrea Garcia Bravo; Dario Acha; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Mercury contamination; Soil remediation; Methylmercury; Mercury methylation; hgcA; Community composition; Bacteria; Landscape; Biologi med inriktning mot mikrobiologi; Biology with specialization in Microbiology;

    Abstract : Accumulation of mercury (Hg) in soil originating from both natural and anthropogenic sources poses a major hazard to environmental and human health. Inorganic Hg(II) in soil can be transformed to highly toxic methylmercury (MeHg) mainly via methylating microorganisms. READ MORE

  4. 2. Unraveling the importance of solid and adsorbed phase mercury speciation for methylmercury formation, evasion and bioaccumulation

    Author : Sofi Jonsson; Erik Björn; Ulf Skyllberg; Erik Lundberg; Per Persson; Robert Mason; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; mercury; methylmercury; aquatic systems; estuary; Hg; MeHg; bioaccumulation; methylation; demethylation; evasion; sediment; water; terrestrial sources; atmospheric sources; climate change; eutrophication;

    Abstract : Monomethylmercury, MeHg, is formed under anoxic conditions in waters, sediments and soils and then bioaccumulated and biomagnified in aquatic food webs, negatively effecting both human and wildlife health. It is generally accepted that precipitation of mercury, Hg, and adsorption of Hg to e.g. READ MORE

  5. 3. Mercury species transformations in marine and biological systems studied by isotope dilution mass spectrometry and stable isotope tracers

    Author : Lars Lambertsson; Wolfgang Frech; John Munthe; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Analytical chemistry; Mercury; methylmercury; ethylmercury; Thimerosal; speciation; methylation; demethylation; brackish water sediment; natural waters; GC-ICP-MS; species-specific isotope dilution; isotope enriched tracers; Analytisk kemi; Analytical chemistry; Analytisk kemi; analytisk kemi; Analytical Chemistry;

    Abstract : This thesis focuses on the implementation of species-specific isotope dilution (SSID) methodology and stable isotope tracers to determine mercury species occurrence and transformation processes in-situ and during sample treatment. Isotope enriched tracers of methyl-, ethyl- and inorganic mercury were synthesised and applied in different combinations to marine and biological samples. READ MORE

  6. 4. Unraveling the importance of thiol compounds on mercury speciation, uptake and transformation by the iron-reducer Geobacter sulfurreducens

    Author : Mareike Franziska Gutensohn; Erik Björn; Ulf Skyllberg; Jeffra K. Schaefer; Vera Slaveykova; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; mercury; low molecular mass thiols; speciation; uptake; methylation; reduction; Hg 0 ; Hg II ; MeHg; Geobacter sulfurreducens; ICP-MS; LC-MS MS; X-ray absorption spectroscopy; cell physiology;

    Abstract : The biogenic methylation of inorganic, divalent mercury (Hg(II)) by methylating microorganisms leads to formation and bioaccumulation of monomethyl mercury (MeHg) in the environment and can cause severe damage to ecosystems and human health. Diverse microorganisms carry the gene sequence hgcAB and are able to methylate Hg(II) intracellularly. READ MORE

  7. 5. Formation, uptake and bioaccumulation of methylmercury in coastal seas : a baltic sea case study

    Author : Aleksandra Skrobonja; Erik Björn; Agneta Andersson; Anne L. Soerensen; Marc Amyot; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Mercury; methylmercury; bioaccumulation; mesososm; isotope tracers; methylation; demethylation; stability constant; kinetic model; coastal sea; ICPMS; LC-MS MS;

    Abstract : Methylmercury (MeHg) is a potent neurotoxin which can bioaccumulate to harmful levels in aquatic food webs. Methylmercury formation is a predominantly biotic process which involves phylogenically diverse microorganisms (e.g. iron- or sulfate-reducing bacteria). READ MORE