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Study of behaviour of selected elements in soil profiles on the Alsar deposit, North Macedonia.
Fizková, Karolína ; Mihaljevič, Martin (advisor) ; Vaňková, Maria (referee)
This thesis is dealing with the behaviour and mobility of hazardous elements Tl, Hg and As occurring in anthropogenic soils on the heaps of the former Alshar deposit in North Macedonia. As, Sb and Au mining had been taking here since the 15th century, peaking during the 19th and first half of the 20th century. Local soils were thus created by periodic layering of tailings of varying age and origin. Nowadays, the area is known mainly for its large number of unique mineral phases, as well as for its extensive possibilities for soil contamination research. The contents of the elements in the samples were exceptionally high and without optimisation of measurement and appropriate dilution would exceed the upper limit of detection of the analytical methods. Arsenic and Tl occur on average in the tens to hundreds of mg/kg, while Hg occurs in the hundreds of mg/kg. The behaviour of the hazardous elements was assessed in relation to soil characteristics, including granulometry, pH, cation exchange capacity, total carbon and sulphur content, or content of Fe, Mn and Al oxides. Correlation with concentrations of other elements was also taken into account. In addition, an isotopic ratio of ε 205 Tl was determined for Tl in the selected samples. However, from the complete measurement results, it was very...
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Arsenic speciation in mining wastes - case studies in systems dominated by ferric sulfoarsenates
Jelenová, Helena ; Drahota, Petr (advisor) ; Filippi, Michal (referee) ; Jurkovič, Ľubomír (referee)
The aim of the thesis is to study behavior and mineralogy of arsenic in mine wastes with high levels of FeIII and SVI . Three methodological studies are related to (i) identification and characterization of secondary arsenic phases using a Raman spectrometry, (ii) chemical fractionation of arsenic in mine waste materials as observed by optimized sequential extraction, (ii) and investigation of thermodynamic properties of zýkaite. The mineralogy and mobility of arsenic was studied in mine waste material of five dumps located at three sites (Kaňk near Kutná Hora, Jedová jáma near Vejprty, and Dlouhá Ves) and in stalactite samples from two abandoned underground mines (Plavno and Mikulov near Teplice). Mineralogical and geochemical characterization of samples included standard methods and techniques. Chemical composition of solid and liquid (pore water, leachates) samples was performed using a XRF, ICP OES, ICP MS, etc. X-ray diffraction, Raman spectrometry and electron microscope equipped with microanalysis were the most frequent techniques used for mineralogical characterization of the solids. The results showed that the speciation of arsenic in the solid phase significantly varied among the studied sites and was a function of total concentration as well as proportion of the major components of...
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Distribution of arsenic in the soil of gold mineralizations in Central Bohemian metallogenetic zone
Řeháček, Jan ; Drahota, Petr (advisor) ; Kindlová, Helena (referee)
Univerzita Karlova v Praze Přírodovědecká fakulta Ústav geochemie, mineralogie a nerostných zdrojů Obsahy arzenu v půdách zlatonosných ložisek středočeské metalogenetické zóny Bakalářská práce Jan Řeháček Vedoucí bakalářské práce: doc. Mgr. Petr Drahota, Ph.D. Praha, 2016 Summary This bachelor thesis reviews scientific publications regarding high concentrations of arsenic in soils of natural geochemical anomalies and former gold mines in the Central Bohemian Metallogenic Zone. High concentrations of arsenic in these areas originates primarily from sulfide minerals which are associated with gold mineralization. Arsenopyrite and pyrite are the most important primary As carriers in the bedrock. Due to natural weathering of sulfide minerals hosting rocks, release of arsenic and other potentially toxic elements into the surrounding environment takes place. This presents danger not only to soil fauna and flora but also to local inhabitants as contamination may also affect water sources in the area. At the beginning of this thesis some general aspects of the presence of arsenic in the environment are described, followed by chapters about the Central Bohemian Metallogenic Zone and its sites with anomalous concentration of arsenic in soil.
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Arsenic toxicity and hyperaccumulation in plants and their potentail use in phytoremediation
Gímeš, Lukáš ; Mašková, Petra (advisor) ; Podlipná, Radka (referee)
Arsenic is classified as a heavy metalloid. Small amounts of arsenic can be found in the environment naturally, but human activity constantly increases the amount of arsenic in the soil. Increasing arsenic contamination of the soil causes serious health problems for both animals and humans. Due to its toxicity, it can also cause considerable problems for plants. Arsenic negatively affects a number of processes in the body of plants, such as oxidative stress or the metabolism of important macromolecules. Photosynthesis is a physiological process that is the most affected by arsenic toxicity. Closely related to photosynthesis are the growth properties of plants. Negative effects that arsenic has on many biochemical, physiological and morphological processes in the plant body, we must understand the uptake, translocation and detoxification of arsenic in the plant body. Arsenic hyperaccumulators are plants that can accumulate orders of magnitude higher concentrations of As and better manage the phytotoxicity of this contaminant than non-hyperaccumulating plants. Hyperaccumulation of heavy metals is associated with changes in the physiological properties of plants. A common characteristic of hyperaccumulators is that they can accumulate the higher concentrations of metals they in the aboveground parts...
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Speciation of arsenic in fluvial systems
Jaxylykova, Anastassiya ; Drahota, Petr (advisor) ; Peřestá, Magdaléna (referee)
4 Summary This bachelor work is devoted to the distribution of the increased concentrations of arsenic in fluvial systems near the villages of Mokrsko and Smolotely in the Central Bohemian region of the Czech Republic. Arsenic in these areas is found in sulfidic minerals associated with gold- bearing mineralizations in the bedrock. Due to the toxicity of arsenic, natural weathering of the mineralized rocks represents a danger for the population of these sites. The theoretical part of the work is devoted to general concepts of the occurrence and concentrations of arsenic in different environments. In the practical part, a small separate study is presented, which studies the concentration of arsenic in fluvial sediments and stream water of the study sites. The results show that the highest arsenic concentrations in the fluvial sediments are almost the same (500- 550 mg/kg). The highest dissolved arsenic concentration was found at Mokrsko (360 g/l), while the highest aqueous arsenic at Smolotely was 160 g/l. Keywords: Arsenic, fluvial sediments, stream water, arsenic contamination
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Synthesis and separation of arsenic-glutathione complexes
Balcárová, Barbora ; Petry-Podgórska, Inga (advisor) ; Červený, Václav (referee)
The arsenic-glutathione complexes are very unstable in solution and tend to decompose during separation in liquid chromatography. The aim of this work was to develop a relatively fast method of the synthesis and storage conditions for the arsenic-glutathione complexes. The thesis is focused on synthesis, stability in-solution and separation of arsenicglutathione complexes. The synthesis was carried out in solution of 2 mM TCEP (tris(2carboxyethyl)phosphine) in water and with excess of the glutathione. Solutions of 20 ppb arsenic-complexes were consecutively measured after 1h, 2h, 3h, 4h and 24 hours of synthesis. The results confirmed stability of the arsenic-complexes in the reaction mixtures over 24 h. The arsenic-glutathione complexes were separated using a reversed phase high performance liquid chromatography (RP-HPLC) coupled with inductively coupled plasma - mass spectrometry (ICP-MS). The chromatographic method was developed using Aeris widepore 3.6u XB-C18 250x2.10mm column. Isocratic and gradient elutions were compared using several compositions of mobile phases and time of the separation. Methods were tested using samples of synthesized arsenic-glutathione complex (DMAs(GS)). An application of the isocratic elution enabled elimination of time needed for the separation and conditioning of...
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Effect of heavy metal ions on Norway spruce embryos
?or?ević, Dragana
Aim of this work was to evaluate effect of copper and arsenic on Norway spruce embryogenic cell masses (ECMs) in different concentrations during 14 days proliferation period but as well during maturation and germination stages. Copper in lower concentrations increased the growth of ECMs while in higher concentrations growth was inhibited. Arsenic in concentrations 50, 250 and 500 uM showed very high toxicity and after 14 days proliferation period all ECMs were dead. In experiments with lower concentrations (10 and 25 uM), control had highest proliferation ratio while arsenic had insignificant difference on growth. Cell line I-1-3 had higher proliferation ratio and produced more somatic embryos during maturation in comparison with cell line III-3-3, respectively. After maturation certain number of abnormally developed cotyledonary somatic embryos was obtained. Norway spruce as a fast growing conifer tree is one of the most widely planted spruces and one of the most economically important species in Europe. The results of this thesis can help to understand effect of two tested metals on somatic embryogenesis but as well can be used for investigation of two tested clones in polluted soils.
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Distribution of arsenic in the soil of gold mineralizations in Central Bohemian metallogenetic zone
Řeháček, Jan ; Drahota, Petr (advisor) ; Kindlová, Helena (referee)
Univerzita Karlova v Praze Přírodovědecká fakulta Ústav geochemie, mineralogie a nerostných zdrojů Obsahy arzenu v půdách zlatonosných ložisek středočeské metalogenetické zóny Bakalářská práce Jan Řeháček Vedoucí bakalářské práce: doc. Mgr. Petr Drahota, Ph.D. Praha, 2016 Summary This bachelor thesis reviews scientific publications regarding high concentrations of arsenic in soils of natural geochemical anomalies and former gold mines in the Central Bohemian Metallogenic Zone. High concentrations of arsenic in these areas originates primarily from sulfide minerals which are associated with gold mineralization. Arsenopyrite and pyrite are the most important primary As carriers in the bedrock. Due to natural weathering of sulfide minerals hosting rocks, release of arsenic and other potentially toxic elements into the surrounding environment takes place. This presents danger not only to soil fauna and flora but also to local inhabitants as contamination may also affect water sources in the area. At the beginning of this thesis some general aspects of the presence of arsenic in the environment are described, followed by chapters about the Central Bohemian Metallogenic Zone and its sites with anomalous concentration of arsenic in soil.
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Separation of toxicologically relevant arsenic species for speciation analysis by RP-HPLC-ICP-MS
Kanásová, Mária ; Matoušek, Tomáš (advisor) ; Červený, Václav (referee)
The thesis is mapping possibilities of separation of toxicologically relevant arsenic species complexed with peptides by reversed-phase high-performance liquid chromatography-inductively coupled plasma mass spectrometry (RP-HPLC-ICP-MS). The C18 chromatography column and gradient elution of the mobile phase (0,1% formic acid with gradient of acetonitrile) was used. At these conditions the separation of simple arsenic species - arsenite (As(III)), arsenate (As(V)), monomethylarsenic acid (MA(III)), monomethylarsenous acid (MA(V)), dimethylarsenic acid (DMA(III)) and dimethylarsenous acid (DMA(V)) was not successful. However, separation of arsenic- -glutathione complexes - arsenic triglutathione (ATG), methylarsenic diglutathione (MADG) and dimethylarsenic glutathione (DMAG) was obtained. Several chromatographic peaks were observed at higher concentration of acetonitrile in mobile phase. The analysis of two in vitro methylation mixtures was also examined. Mixtures contained arsenite (As(III)), S-(5'-adenosyl)methionine chloride (SAM), tris(2-carboxyethyl)phosphine (TCEP) and arsenic(3+)methyltrasferase enzyme (AS3MT) probably participating in human arsenic metabolism. Second mixture also included glutathione (GSH). Several chromatographic peaks of complex species were obtained by analyzing these...
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