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This diploma thesis dealt with the area of toxic substances in food and their impact on public health. The work aims to describe the types and occurrence of toxic substances, analyze the current state of toxic substances found in food and define their impact on public health. It also aimed to describe the effects of toxic substances on the human body. The work is divided into theoretical and practical part. The theoretical part first introduces the historical origins of the scientific field of toxicology. It also defines basic toxicological terms and parameters. Describes factors affecting the toxicity of substances, absorption, distribution, the effect of metabolism and excretion of toxic substances. Objective 1 was met by describing the basic types of natural and foreign toxic substances. Furthermore, their occurrence was described and their impact on public health was defined. The effects of toxic substances on the human body have been described in relation to Objective 2. The effects of toxic substances can manifest themselves in many ways. It can be mild nausea or even death. The second half of the theoretical part deals with toxic substances in the food industry. It describes a massive increase in the use of chemicals in food and agriculture, whether they are various pesticides, crop treatments, or various additives that are added to foods to improve some of their properties. Some of these substances can have an adverse effect on health, and when we consume them in food in quantities that are permitted by legislation, no one has a clear idea of what the consumption of additives and pesticide residues in food can cause us in the long term. The practical part examines the awareness of the general population about toxic substances in food and their impact on public health. The practical part was created using quantitative research, which was conducted through a questionnaire survey. The questionnaire was created on the basis of the theoretical part of the work. The research group consisted of 114 respondents from the general population. The questionnaire consisted of 21 questions that examined the addressees' awareness of toxic substances in food and public health. The results of the research survey corresponded the given knowledge to two research questions, which asked the work whether the public is oriented in the field and whether they differ according to their education. The results were graphically processed and evaluated. It was found that the public is not very familiar with toxic substances in food and public health. The work can serve as a comprehensive educational material on toxic substances in food and public health. The theoretical benefits of this work include an analysis of the current state of toxic substances in food, including a description of control authorities and relevant legislation in the field of toxic substances in food and public health. Among the practical benefits is the creation of a questionnaire that examined public awareness of this issue. Based on the achieved results, follow-up work can be proposed - for example, exploring the possibility of raising public awareness of toxic substances in food.

The effect of terbuthylazine-2-hydroxy (HTBA) on human cell cultures of HepG2 and MG63 was investigated by method of acute in vitro toxicity tests at concentrations of 0; 0.58; 0.8; and 8 mg/l. The experiment has two parts. In the first part overall biological activity (mortality, specific growth rate, dilation - cytoskeletal activity) was examined using a Nikon Biostation IM-Q microscopic device. The evaluation of the acquired images took place visually and the significant effect of HTBA was not confirmed. In the second part of the experiment, performed on a high-resolution NanoTruth light microscope, data corresponding to a concentration of 8 mg/l HTBA and data from a control experiment without added HTBA tested on HepG2 cell culture were evaluated. The evaluation of the obtained image data was performed mathematically, using the optical flow method. From the resulting values of optical flow, lower intracellular dynamics was found in the exposed sample than in the sample without the presence of HTBA. This suggests a possible negative effect of HTBA on the tested cell culture.

The bachelor thesis "Toxic substances and their effects to human health" deals with characteristics of selected historical periods of toxicology. It describes the basic concepts of toxicology. It briefly characterizes toxic substances of plant and animal origin. More attention is paid to mycotoxins, especially aflatoxins, fumonisins, ochratoxins and zearaleon. A very important part of this thesis is the prevention of the effects of toxic substances on human health and describes the partial measures that are necessary before consumption or preparing of food. The practical part examines the awareness of university students about important toxic substances in food. It assesses whether these students recognize the desired mold species on food. Next it is interested in what precautionary measures are taken by university students before consuming and preparing food. The conclusion of the thesis shows that the know-how of university students is relatively high.

Toxicology is a scientific discipline dealing with the influences of dangerous substances on living organisms. The negative effects of some substances have been known since the prehistoric times and the human race has had to face them until today. The impact of these substances on human organisms may be caused either deliberately (e. g. misuse of chemical substances during war conflicts) or unintentionally (e. g. intoxication by poisonous gases released from fire). The current knowledge of the field of toxicology enable to characterise the dangerous substances, to define their effective, toxic and lethal doses and concentrations and to give first aid to the people affected. The knowledge of the first aid procedure in case of intoxication of poisonous gases is crucial for the rescue of human life and moderation of the toxic effects. In connection to the universal first aid procedure, i. e. the patient's rescue out of the contaminated area and calling of the rescue service, the person affected has to receive an adequate immediate pre-hospital care. Based on these findings, procedures used in cases of intoxication in pre-hospital emergency care and emergency medicine are listed. The aim of the theoretical part of this diploma thesis is a comprehensive overview of current theoretical and professional knowledge in the field of chemistry, toxicology and emergency medicine. This knowledge is subsequently applied to the overall management of pre-hospital emergency care for patients intoxicated with toxic gases. The research part includes a retrospective statistical analysis of the number of cases of carbon monoxide intoxication in Vysocina Region, application of theoretical knowledge in the form of analyses of cases of intoxication and creation of a preventive programme with the help of a questionnaire survey which asked the public about their awareness of the risks and dangers of carbon monoxide. In addition, educational material was created. The thesis also tried to answer the research question "How serious is poisonous gas intoxication in pre-hospital emergency care and emergency medicine?" From the point of view of pre-hospital emergency care, the average daily death rate caused by poisonous gas intoxications in the Vysocina Region is four patients per year. When this number is compared with the total number of patients' deaths, it shows a less serious problem. The most common source of carbon monoxide poisoning turned out to be a gas appliance. The rescuers recorded the highest number of carbon monoxide detector activations in 2015. Informing the public in the form of a questionnaire survey has clearly shown that there is persisting confusion of carbon monoxide properties with carbon dioxide ones. This diploma thesis is aimed at specialists providing pre-hospital emergency care i. e. health rescue services and also fire rescue services for the purpose of statistical comparisons with other providers and subjects, or for educational purposes in the context of crisis preparedness. In addition, the work is recommended to the general public to ensure greater awareness of poisonous gas intoxications. This thesis brought a comprehensive overview of this issue which can be used for the purpose of informing, educating and creating the basis for further comparison.

The thesis compares variability of mercury concentration among adult and juvenile fish in order to streamline monitoring of water environment contamination. In terms ov thw thesis there were monitored two localities: Labe Děčín and Labe Kozly. Adult fish were caught usingdeep-water electrofishing equipment and juvenile fish were caught using back-pack electrofishing equipment. Two variations of mercury concentration were compared, one in muscle of particular adult fish species, second in whole bodies of juvenile fish. Mercury concentrations were also compared among particular juvenile fish fish species in particular localities. All analyses were performed using spectrophotometer AMA 254. It was proved that analyses of juvenile fish are suitable and more cheaper than analyses of adult fish, when it comes to monitoring.

Since 1986 extensive reclamation works have taken place in the area. Aim of this works is to mend the damaged environment, eliminate impact of uranium processing, reduce contamination of ground water and radiation effects on the area. However after 29 years of reclamation works, risks of chemical and radiation toxicity are still present. Massive development of uranium mining occurred at the beginning of 20th century. Czech republic was not an exception and czech government decided to build chemical processing plant of uranium under a code name MAPE. chemical processing plantwas built near village Mydlovary, in the southeaster part of Czech republic. Construction began in 1959. Operation started in 1962. Uranium was processed either by acidic or alkalic leaching. During the operation of the plant 36 million tons of sludge were stored in nearby sludge beds. Operation of MAPE ended in the year 1991. This thesis focuses on problems of chemical toxicity in former uranium processing plant MAPE Mydlovary and nearby area. Primary aim was to assess potential risks of chemical toxicity resulting from MAPE operation which could influence health of former employees, citizens of nearby villages and the environment. In order to determine the risks it was necessary to analyse chemical substances used to process uranium, possible signs of uranium intoxication of living organisms, quality and direction of ground water flow in wider area of interest. Among substances used to process uranium were different kinds of gasoline, diesel, ammonia, nitric acid, sulphuric acids and its salts, sodium carbonate and barium chloride dyhydrate. In comparison to dangerousness of particular substances it was found that most occurring types of damage are types of damage to skin or eyes due to irritant or caustic effects. It was difficult to analyse the influence of uranium intoxication on living organisms because of limited availability of useful and relevant information . Therefore assessment of possible effects were established as the result of previous studies. Former employees of MAPE could have been exposed to several kinds of uranium compounds (UO2, UO3, (NH4)2U2O7), therefore effects of intoxication by these compounds were taken into the consideration. Most cases of chemical intoxication were localized in the renal and respiratory systems of living organisms. Ground waters of wider area of interest were estimated as main carrier of potential chemical intoxication of residents of nearby villages and environment. Analysis of quality and direction of spreading showed that villages close to processing plant can use ground water only for irrigation (in the village Mydlovary ground water cannot be used even for irrigation) . Furthermore there is a small risk of contamination of collecting borehole S4 near the city of Zliv. Water from this borehole is drinkable and worsening of the quality of this water could result in exceeding limits set by decree no. 274/2003. Nowadays former chemical processing plant of uranium MAPE Mydlovary represents one of the most severe ecological burdens in Czech republic. Reclamation works significantly reduce negative impacts of chemical processing plantand without these works present situation would pose both real threat to ecology and protection of public health.

This thesis deals with problems of toxicological labs at secondary school. The theoretical part provides an introduction to all the topics, the practical part consists of the processing instructions for laboratory tasks, accompanied by illustrations, photos, and supplementary questions. Suplement contains solutions of these issues.

The object of this thesis is the assessment of fish contamination by selected foreign substances as toxic metals, polychlorinated biphenyls and pesticides in 31 selected fishing grounds. The monitoring was realized between years 2006 and 2010. Fish were caught by electric device and fishing rods. Concentrations of Hg, Cd, Pb, PCB, DDT, HCH and HCB in fish muscle tissues were monitored. Common bream (Abramis brama) was selected as a reference species for a comparison of the monitored sites. The results of analysis were compared with valid hygienic limits. Overrun of hygienic limit for some of the monitored pollutants were observed in 18 localities. We found mercury as a major pollutant in the aquatic environment.

Project brought new scientific results in the field of chemical composition, physical and toxicological characterization of street dust and particulate matter. Chemical analyses and statistical methods including receptor modelling result in identification their sources.

The diploma thesis deals with the influence of dangerous substances in electric aparatus on environment and also on human. The aim of this diploma thesis is to describe toxicological characteristics of dangerous substances in electric apparaus and to find out people´s awareness about electro apparatus hazardousness and electric waste by mean of questionnaires. The thesis first descibe the laws concerning this problem either from the view of dangerous substances or from the view of dangerous waste. Furthermore in the thesis the data taken out of two age groups by questionnaires were elaborated. The questionnaires were focused on the knowledge of dangerous substances and dangerous waste. Toxicological characteristics of dangrous metals are also descbibed in this part.

My Bachelor's work is engaged in complicated procedure of the beginning and constitution of branches of science - military radiobiology and military toxicology in conditions of former country Czechoslovakia. This process specification required to respect the range of complicated troubled levels where each of them could create a theme of individual task: - the second World War, its results and impact to military and political sphere; - formation of divided world, conditions and manifestation of "Cold War"; - new phenomenon-Weapons of Mass Destruction - research and development in this sphere in divided world; - development of home politics in Czechoslavakia and its incorporation to the commonwealth of USSR; - the Czechoslovak military and its health service development after the Second World War, the projection of political development turning points into this area; - the founding of Military medical academy in Hradec Králové as military-medical tutorial and scientific centre; - background of constitution mentioned branches and their prominent characters. My Bachelor's work in closes, sorts and searches the sequences of these problematic levels, it tries to highlight and mediate especially lesser-known pieces of knowledge from military health service and educational system history for public.

This diploma thesis dealing with a simulated accident of a rail tanker in the railway station in Jihlava with subsequent leakage of ammonia has been prepared in the form of public and available information that provides a brief overview about the topic. In the introduction, possible types of extraordinary events are described with individual examples. In another part of the thesis, extraordinary events in traffic are mentioned as well as accidents connected with leakage of dangerous substances. The follow-up chapter deals with the issue of emergency planning, aimed particularly at leakage of ammonia. The remaining part is devoted to the integrated rescue system. Another chapter deals with ammonia toxicology with examples. The following part concerns railway haulage, including rail transport of ammonia. The following chapter describes the chronology of an extraordinary event with the follow-up solution. In the diploma thesis, research of awareness of the general public about ammonia is presented. The conclusion contains specification of problems that occurred during preparation of this paper. Also comparison with specialized literature is provided as well as the author{\crq}s own ideas.

Review presented on the occasion of the significant life jubilee of Prof. J. Tesar, MD, DrSc., 16.12.2002 in the Medical House in Prague deals with the development and application of analytical technologies in toxicological practice in the last fifty years, with demands on decreasing the size of biological samples, detection limits achievable, with possibilities of interpretation deduced from analyses of alternative matrices. The paper also informs about scientific guidelines applied in Europe with attention focused on the reliable detection of illicit drugs in the workplace or drugs and driving. Based on more advanced analytical strategy, more complete and more precise information can be achieved and consequently more perfect interpretation based on objective evidence can be gained and it can comply to "Evidence Based Forensic Toxicology".

Toxicological examination of biological samples of a certain case is a complex task which demands knowledge not only of modern analytical methods but also of the fate and effects of xenobiotics in organism. The evidence of unknown drugs and poisons in biological material is a difficult matter due to the broad variety of harmful substances and their unlimited possible mixtures, due to variable concentrations in a broad unpredictable range. In toxicology, there is the important question of the completeness of evidence and correctness of chemical identification of individual substances. Generally, the validation of qualitative methods is less developed than the validation of quantitative methods. The evidence of unknown harmful substances in biological samples requires often the individual consideration about optimal attitude to a nonstandard toxicological case and prevent from application of uniform procedures in fixed combinations.

Due to the action of light and oxidation some drugs applied to and developed on a thin layer give a colour reaction. As a result of photooxidation artefacts may develop directly on the thin layer.

Embryotoxic effects of 25 mycotoxins were investigated in two-, three- and four-day chick embryos; the results were evaluated on the eighth day of development. The embryotoxicity ranged from 0.0001 to 0.1 microgram per embryo in T-2 toxin, aflatoxin B1, G1, B2 and M1, cytochalasin E, ochratoxin A and PR-toxin; from 0.1 to 1.0 microgram per embryo in sterigmatocystin, aflatoxin G2, vomitoxin (4deoxynivalenol), patulin, rubratoxin B, secalonic acid D, mycophenolic acid, and from 1.0 to 100 micrograms per embryo in penicillic acid, cyclopiazonic acid, tenuazonic acid, citrinine, brevianamide A, zearalenone, fusaric acid, griseofulvin, kojic acid and 8-methoxypsolaren. Acute cardiotoxic effects were observed in PR-toxin, patulin, rubratoxin B, penicillic acid, citrinine and zearalenone. Teratogenic effects with a spectrum of different embryonal malformations occurred in T-2 toxin, ochratoxin A, PR-toxin, patulin, secalonic acid D, mycophenolic acid and citrinine. The embryotoxic effects demonstrated in chick embryos correlated with the well-know literary data on mammals. Considering the different chemical composition and biological effects of mycotoxins, we suppose that the embryotoxicity test of chick embryos will also be suitable for testing other biologically active substances in the environment.

A simplified method for combining thin layer chromatography and infrared spectroscopy was developed. It concentrated compounds in separation just on the treated original chromatogram (after a special cutting out zones). Reduced number of operations substantially decreased losses of studied substances. Minimal amount of a substance for producing the spectrum was about 30 micrograms.

The development of the chemical industry and subsequent intensive use of chemical products in other industrial branches, incl. e.g. agriculture, leads to the demand of hygienic and ecological wholesomeness. A sufficiently accurate background for this evaluation can be provided by experimental disciplines such as toxicology and ecotoxicology. The contemporary development of their methodology has reached a state which provides adequate guarantees for their application in particular in legislative activities. Not only final products are evaluated but also intermediary products in chemical production and finally also waste products. Evaluations of biological wholesomeness are implemented within the framework of international cooperation at levels which make it possible to use the results of toxicological and ecotoxicological evaluation also in other countries. With regard to the extensive character of the subject, attention is paid in the submitted paper in particular to basic toxicological and ecotoxicological tests.

In opening the paper, the authors present a brief outline of the fundamentals of nuclear magnetic resonance. Using selected cases from practice, they demonstrate the use of nuclear magnetic resonance for the purpose of forensic toxicologic analysis. The method is particularly suitable for identifying unknown organic compounds and for analysing mixtures of substances.