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Cycling of mercury and mercury species in the environment
Finsterlová, Hana ; Diviš, Pavel (referee) ; Dočekalová, Hana (advisor)
This bachelor’s thesis deals with the role of mercury in an environment. It summarizes informations about properties of mercury and its species. The thesis is engaged in the presence of mercury in atmosphere, water, soil and sediments. It deals with individual mercury intakes into the environment, anthropogenic or natural, and it follows transport of mercury between individual components of environment. Part of this thesis is given to the accumulation of mercury and mercury species into plants and organisms. It points out the toxicity of mercury, mercury species, and their effect to human organism. In the last chapter there is a resume and description of the instrumantal methods, which are commonly used for determination mercury and its compounds.
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Presence of heavy metals near the way Rudná
Chovanec, Petr ; Pavlovský, Jiří (referee) ; Doležalová Weissmannová, Helena (advisor)
These diploma thesis is focused on assessment of hazardous metals in soils near the road Rudná in Ostrava. Seventeen sampling sites have been chosen along this road, samples from this sites were collected in three series. The amounts of mercury, lead, copper, cadmium, zinc, vanadium and manganese were determined. There was also assessed contamination of selected sites using contamination factor and degree of contamination.
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Development of Gel Techniques for in situ Measurement of Bioavailable Metals in Soils and Sediments
Kovaříková, Vladěna ; Sommer, Lumír (referee) ; Janoš, Pavel (referee) ; Dočekalová, Hana (advisor)
The doctoral thesis deals with usage of gel techniques for in situ measurement of bioavailable metals in soils and sediments. The DGT technique was applied to soil samples from the localities of Zlín, Tuřany and Chrlice for estimation of bioavailable metals in soils. These soils were amended by sewage sludges in years 1980-1987. The experiment using diffusive gels with different pore size, APA and RG gels, has shown that the DGT can be used for assessment of trace metal soil complexes - small inorganic and larger organic. The results obtained by DGT measurements were approximately up to two orders of magnitude lower than metal concentrations obtained by leaching with sodium nitrate. The leaching with sodium nitrate does not provide true reflection of metal availability to plant root system and soil microorganisms and the DGT technique seems to be a better predictor of metal bioavailability. Only small differences between undisturbed and homogenized soil samples were found out by application of DGT to soil samples from localities of Veverská Bítýška and Ostrovačice. The undisturbed soil is not homogenous and the DGT unit gives information only about the part of the soil which is in direct contact with the unit. The procedure with soil slurry can be recommended for the characterization of large soil areas and estimation of bioavailable metals in soils. Gel techniques were also used for the study of processes occuring in sediments. Mercury species and other metals were analysed in surface water, pore water and sediments collected from two sampling sites in the Dele River in northern France. This river had been polluted during the last century by the activity of Métaleurop factory, which dealt with metal ore treatment. The application of DGT technique using two specific ion-exchange resins, Chelex-100 and Duolite GT-73, provided assessment of mercury in sediment pore water. DGT and DET techniques together with centrifugation provided also high resolution depth profiles of Fe, Mn, Zn, Pb, Cr and Cd in pore water. It is not possible to determine which sampling site was more contaminated. Only small differences in mercury species and metal content were observed between sampling sites. The Dele River can be classified as contaminated river according to total mercury content in sediments and as slightly contaminated river from the point of view of methylmercury content. Correlations between mercury species and sulphide content confirm that total mercury and sulphide content count among factors influencing the mercury release to pore water and controlling processes of methylation and demethylation. Only low toxicity of sediment slurries was found out by the bioluminiscence test with Vibrio fischeri. The results of doctoral thesis demonstrate gel techniques as a very good tool in environmental analysis.
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Characterization of the resin gels for mercury determination by DGT technique.
Finsterlová, Hana ; Řezáčová, Veronika (referee) ; Diviš, Pavel (advisor)
The aim of this thesis is testing of resin gels used in diffusive gradients in thin films technique (DGT) for determination of mercury in natural waters. The sorbets, chosen for preparation of resing gels were: Duolit GT- 73, Spheron- Thiol, and Chelex 100 and newly modified sorbent Iontosorb AV. At the beginning of work, the preparation procedure of all resing gels was optimized. After optimalization of preparation procedure the resin gels were tested in mercury model solutions. The recovery test and time dependence test were performed. When the basic tests were finished, they were followed by the tests of influence of natural ligand (humic acids and chlorides), and other parameters (above all pH and ionic strenght), on mercury determination by DGT technique.
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Selected inorganic pollutants in foodstuffs
Kroupová, Kateřina ; Vítová, Eva (referee) ; Vitoulová, Eva (advisor)
This bachelor thesis is focus on occurrence of inorganic pollutants in foodstuffs. The introduction is dedicated to apperance of individual selected elements in foodstuffs. Concentration of these elements is very important factor for examination of toxic effects for the human organism. If we want to avoid the harmful effects to the human organism, we have to define border limits. Work is based on the legislative of Czech republic. Second part of this study is focused on the biological monitoring. The biological monitoring is important for precautionary measures. In the third part of this study are described toxical effects of these elements to the human organism. Before qualitative and quantitative analysis by instrumental techniques is important to properly take the sample. In the fourth and fifth part of this work are mentioned methods used for determination of these elements and metods of taking samples. This bachelor thesis provide complex view on the problems of pollutants in foodstuffs and it should be used as a base for following diploma thesis.
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Application of Diffusive Gradients in Thin Films Technique in Food and Environmental Analysis
Reichstädter, Marek ; Čáslavský, Josef (referee) ; Urík,, Martin (referee) ; Diviš, Pavel (advisor)
Tato dizertační práce zkoumá vývoj techniky difúzního gradientu v tenkém filmu (DGT) pro stanovení rtuti (Hg) a dalších stopových kovů a dále rozšířené možnosti použití této techniky. Technika DGT je v této práci vyvinuta pro stanovení Hg a dalších stopových prvků v různých kapalných médiích. Dvě rozdílná sorpční média specifická pro rtuť byla testována pro použití v technice DGT – Purolite S924 a cysteinem modifikovaná aminopropyl silika (CAPS). Purolite S924 je komerčně dostupný chelatační iontoměnič, CAPS byla připravena v laboratorních podmínkách imobilizací cysteinu na 3-aminopropyl funkcionalizovanou siliku pomocí glutaraladehydu. Obě testovaná sorpční média ukázala slibný aplikační potenciál pro užití v technice DGT díky funkčnosti v roztocích o širokém rozsahu pH i iontové síly. Funkčnost DGT s novými sorpčními médii byla porovnána s technikami DGT s běžně používanými sorbenty Chelex-100 a 3-merkaptopropylfunkcionalizovanou silikou. Hlavní výhodou sorpčních médií Purolite S924 a CAPS je schopnost současného stanovení Hg a dalších stopových kovů (Cd, Pb, Co, Ni, Cu). Vzhledem k odlišným požadavkům na sorpční média používaná v technice DGT nebylo dosud současné kvantitativní stanovení Hg a dalších stopových kovů možné. Doposud byly zapotřebí dvě samostatné techniky DGT – jedna pro Hg a druhá pro další stopové kovy, což zvyšuje množství vzorků pro analýzu a množství použitého spotřebního materiálu. Technika DGT s CAPS byla použita pro stanovení koncentrací kovů v námořních přístavech v Oostende a Zeebrugge na belgickém pobřeží Severního moře. Přestože byla technika DGT původně představena pro použití v analytické chemii životního prostředí, byla v této práci zkoumáno i použití této techniky v analýze potravin. V prostředí rybí omáčky byla ověřena funkčnost techniky DGT a stanoveny difúzní koeficienty Hg a dalších stopových prvků. Technika DGT byla následně použita pro stanovení koncentrace rtuti a dalších stopových kovů v různých komerčně dostupných vzorcích rybí omáčky. Výsledky nově navrhnutého analytického postupu s použitím techniky DGT byly porovnány s výsledky přímé analýzy atomovou absorpční spektroskopií s termální dekompozicí a amalgamací zlatem (TD-AAS) a po mikrovlnném rozkladu vzorků omáčky také s výsledky sektorové hmotnostní spektrometrie s indukčně vázanou plazmou (SF-ICP-MS). Díky předkoncentrační schopnosti techniky DGT byly dosaženy nižší detekční limity ve srovnání s TD-AAS nebo SF-ICP-MS. Technika DGT díky schopnosti oddělení analytů z komplexní matrice rybí omáčky rovněž snížila opotřebení a koroze kovových částí použitých instrumentálních technik.
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Plant bioindicators of heavy metals
Pecinová, Eliška ; Doležalová Weissmannová, Helena (referee) ; Komendová, Renata (advisor)
The urban areas are exposed to high risk of contamination, and some of the plant species can indicate this contamination. For this study, plants which can accumulate heavy metals and meet the requirements for bioindicators were chosen. Lichens, moss, birch, linden, and yew were chosen as bioindicators. Plant samples were collected from the specified localities in Brno, both with and without heavy traffic, then analysed by atomic absorption spectrometry for the contents of Cd, Cu, Hg, Pb and Zn. Copper (max 47,7 mgkg-1) and zinc (max 200 mgkg-1) were detected in concentrations higher than the lower border of potential phytotoxic concentrations. Lichens and mosses were proved as the best bioindicators for most of the contaminants (Cu, Hg, Pb), except for zinc, which was indicated by birch. Linden wasn’t suitable for biomonitoring. The result concentrations in bioindicators were very variable among localities, without visible effect of traffic load, which implies other factors, which outweighed factors of contamination from the nearby traffic.
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Monitoring of mercury and methylmercury content in fish meat and evaluation of risks associated with the consumption of this meat
Křížová, Lucie ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
Mercury and its compounds are one of the most toxic global pollutants in the environment. It occurs in all segments of the environment, and it attains the food chain ang human body by people consuming fish. The theoretical part of this thesis examines the characteristics of mercury, its occurrence, the roots of its pollution, and the toxicity of various forms of mercury. Consequently, the thesis delineates analytical methodologies applied to determine the overall level of mercury and chemical forms of mercury. The practical part focuses on monitoring the level of mercury and methylmercury in 12 extracts of fish meat. The analyzer AMA 254 has been used to determine the level of mercury and methylmercury in these extracts. Based on the level that resulted from the measurements, the thesis concludes a risk that correlates with consuming this type of meat.
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Contamination of soil and sediment by hazardous metals
Pidima, Tomáš ; Komendová, Renata (referee) ; Doležalová Weissmannová, Helena (advisor)
This bachelor thesis deals with soil and sediments from the environmental perspective. For selected heavy metals – cadmium, lead and mercury are given information about their occurrence, characteristics and potential sources of environmental contamination. It is also mentioned legislation dealing with the topic. The limit concentrations in soil and sediments, determination methodology and principles of the most commonly used instrumental analytical methods for these elements are described.
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Use of DGT technique for mercury determination in food liquid flavorings
Habartová, Aneta ; Reichstädter, Marek (referee) ; Diviš, Pavel (advisor)
This bachelor thesis deals with varification of the use of the diffusive gradient in thin films technique (DGT) for food analysis. It focuses on testing a new type of sorption gel containing Purolite S924 as well, commercially available for mercury determination in food liquid flavorings. Theoretical part contents of characteristics and production of fish sauces are described analytical methods for mercury determination and DGT technique. Experimental part focused on optimization of preparation of sorption gel and validation DGT techniques for mercury determination in fish sauces. After validation DGT technique was successfully used for analysis real samples of fish sauces.
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