This paper describes the role of zinc in the natural environment. The attention is focused on natural and anthropogenic sources in the environment. The effect of zinc on the human organism, in particular its biochemical and physiological functions are described. The lack or excess of zinc and its impact on human health is also discussed. Part of this work summarizes the most commonly used methods for the detection of zinc.
- MeSH
- lidé MeSH
- zinek * analýza metabolismus nedostatek škodlivé účinky MeSH
- životní prostředí MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
The aim of this study was to summarize findings about the role of cadmium in the environment. The study includes information about the properties and effects of cadmium on the environment, transport between the different components of the environment and describes natural and anthropogenic sources of cadmium. Furthermore, this work describes the effect of cadmium on the human body and shows its toxicity. The methods of cadmium determination are also summarized in the scope of this work.
This study deals with the role of lead in the environment. It summarizes information about properties of lead and deals with lead intakes into the environment, anthropogenic or natural, and it follows transport of lead between individual components of the environment. Part of this thesis is given to the accumulation of lead into organisms. It points out the toxicity of lead and its effect to human organism. The last chapter summarizes the analytic methods that are commonly used for lead determination.
- Klíčová slova
- bioalumulace,
- MeSH
- látky znečišťující životní prostředí * MeSH
- lidé MeSH
- olovo * analýza metabolismus škodlivé účinky MeSH
- otrava olovem MeSH
- znečištění životního prostředí MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
This study deals with the role of mercury in the environment. It summarizes information about properties of mercury and its species, deals with individual mercury intakes into the environment, anthropogenic or natural, and it follows transport of mercury between individual components of the environment. Part of this thesis is given to the accumulation of mercury and mercury species into organisms. It points out the toxicity of mercury and mercury species, their effect to human organism. In the last chapter there is a resume of the instrumental methods which are commonly used for mercury determination.
The aim of the study was the preparation of a liposome complex with encapsulated lead ions, which were electrochemically detected. In particular, experiments were focused on the potential of using an electrochemical method for the determination of free and liposome-encapsulated lead and determination of the encapsulation efficiency preventing the lead toxicity. Primarily, encapsulation of lead ions in liposomes and confirmation of successful encapsulation by electrochemical methods was done. Further, the reduction effect of the liposome matrix on the detected electrochemical signal was monitored. Besides encapsulation itself, comparison of toxicity of free lead ions and lead ions encapsulated in liposome was tested. The calculated IC50 values for evaluating the lead cytotoxicity showed significant differences between the lead enclosed in liposomes (28 µM) and free lead ions (237 µM). From the cytotoxicity studies on the bacterial strain of S. aureus it was observed that the free lead ions are less toxic in comparison with lead encapsulated in liposomes. Liposomes appear to be a suitable carrier of various substances through the inner cavity. Due to the liposome structure the lead enclosed in the liposome is more easily accepted into the cell structure and the toxicity of the enclosed lead is higher in comparison to free lead ions.
The aims of the study were to determine total mercury concentrations in "rainbow trout Oncorhynchus mykiss (Walbaum)" at their embryo-larval and juvenile stages and to assess mercury concentration dynamics in individual tissues. Samples of rainbow trout were collected at two-month intervals over a period of 18 months (one stock production cycle) at the Velká Losenice trout farm. Feedstuff samples were collected at the same time and analyzed for mercury concentrations. Tissue mercury concentrations were determined in muscle, liver, and kidneys. Analyses were performed using the AMA 254 atomic absorption spectrophotometer. The lowest mercury concentration was found in 14-day-old embryos (hard roe), and the highest concentrations in muscle tissue, liver, and kidneys at the end of monitoring, that is, in rainbow trout aged 18 months. The amount of mercury in feedstuffs showed an increasing trend and ranged between 0.0126 and 0.0859 mg kg(-1). A significant effect (P < 0.001) of mercury intake on mercury concentrations in muscle tissue, liver, and kidneys was demonstrated. Muscle mercury concentrations in 18-month-old market-ready rainbow trout of 0.128 ± 0.048 mg kg(-1) met the criteria for fish meat hygiene.
- MeSH
- chemické látky znečišťující vodu toxicita MeSH
- krmivo pro zvířata MeSH
- larva metabolismus MeSH
- monitorování životního prostředí metody MeSH
- Oncorhynchus mykiss embryologie fyziologie MeSH
- reprodukovatelnost výsledků MeSH
- rtuť toxicita MeSH
- spektrofotometrie atomová metody MeSH
- tělesná hmotnost MeSH
- teplota MeSH
- vývojová regulace genové exprese MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
