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Sewage sludge – a secondary source of environmental contamination with heavy metals
Sysel, Petr ; Zlámalová Gargošová, Helena (referee) ; Komendová, Renata (advisor)
This work deals with the elementary trace analysis of sewage sludge as a potential source of risk elements when applied to agricultural land. A total of 24 samples were analyzed, divided into two sets with different collection dates. The total content of zinc, copper, chromium, lead, mercury and cadmium in sewage sludge, as well as amount of risk elements that are extracted from sludge to water in 24 hours, was determined. Atomic absorption spectrometry was chosen for the analysis. It was found that the risk elements are in sewage sludge in amounts and order Zn (254.68 – 3084.53 mg/kg) > Cu (6.18 – 961.89 mg/kg) > Cr (26.95 – 387 .91 mg/kg) > Pb (0.84 – 155.30 mg/kg) > Hg (0.50 – 4.12 mg/kg) > Cd (0.06 – 2.61 mg/kg). A lower amounts of analyzed metals in the aqueous extracts than their total amounts in sludges were observed. The concentration of mercury and cadmium in the aqueous extracts was below the detection limits. It was evaluated that the risk elements in sewage sludge are found in less water soluble compounds. The results also show that the concentration of risk elements in the sludge does not depend on the number of equivalent inhabitants for which the treatment plant is dimensioned.
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Elemental analysis of selected types of herbal teas
Adámková, Petra ; Hraníček, Jakub (advisor) ; Šíma, Jan (referee)
In this bachelor thesis the concentrations of magnesium, potassium, manganese, zinc, copper, chromium, cadmium and lead in selected herbal teas and their infusions were determined. Teas from two competing producers on the Czech pharmaceutical market were selected for analysis. The aim of this work was a mutual comparison of selected tea samples in terms of their elemental content. An indicative study of the effect of water temperature and leaching time on the release of elements into the solution during the preparation of the pickle was carried out. The applied method included the decomposition of samples in a microwave device in the presence of concentrated nitric acid and analysis of the composition of the prepared solutions using ICP-MS. The results showed that the element contents differ according to the type of plant and according to the producer. Furthermore, it was proven that the leaching time has a greater influence on the release of elements into the solution than the water temperature. In this work, it was also verified that the ICP-MS method was suitable for determining the concentrations of all selected metals due to low detection limits. Key words Mass spectrometry, inductively coupled plasma, herbal teas, metals, microwave decomposition
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Determination of selected elements in potato tubers by atomic absorption spectrometry
Fořtová, Lucie ; Hraníček, Jakub (advisor) ; Kozlík, Petr (referee)
The main aim of this bachelor thesis was a determination of the elements K, Mg, Ca, Na, Zn and Fe in the potato tubers and in their boiled solution using the method of flame atomic absorption spectrometry. The chosen samples were late consumer potato tubers of Granada cultivar (boiling type B). It was necessary to optimize working conditions before the sample analysis. The optimal flow rate of acetylene ranged from 2.0 to 2.5 l/min using the flame acetylene-air. The flame acetylene-nitrous oxide was used only for calcium with flow rate 6.0 l/min. The optimal height of a beam above the burner edge was measured in interval 5 to 7 pieces of defined scale mentioned in a manual for spectrometer GBC 933 AA. Using the optimal conditions, the basic characteristics for individual methods of determination were characterized (LOD, LOQ, LDR, sensitivity, repeatability). Limits of quantification were following: 78, 31, 7.0, 8.0, 190 and 71 μg/l for K, Na, Mg, Ca, Fe and Zn, respectively. The optimal conditions were used for the determination of the selected elements in samples. The solutions were prepared from diversely processed potato tubers (whole, whole without skin, chopped without skin, skin) by boiling into deionized water. After the samples had cooled down, the concentrated nitric acid was added...
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