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Hormonally active substances in the aquatic environment and risk to aquatic organisms and human.
Duisembay, Zhuldyz ; Bušová, Milena (advisor) ; Ezechiáš, Martin (referee)
This bachelor thesis aims to investigate the presence, sources and impacts of hormonally active substances, or endocrine disruptors (EDs), in the aquatic environment. These substances, including long-lived persistent organic pollutants (POPs), e. g. pesticides and polycyclic aromatic hydrocarbons (PAHs), and non-persistent pollutants such as bisphenol A and alkyphenols, directly or indirectly affect the hormonal systems of aquatic organisms and humans. For instance, it was observed, that elevated concentrations of certain progestogens impact fertility, reproductive processes, induce transcriptional changes, and alter sex ratios within fish populations. Numerous studies in the field focus on evaluating the manifestation of EDs in water, their effects on behavior and vital functions of aquatic organisms and humans, and the challenges associated with their detection and removal from the wastewater discharged into the environment. Recent researches have revealed elevated concentrations of specific EDs in various regions, including Czech Republic (significant concentrations of levonorgestrel, megestrol acetate (MGA), drospirenone and dienogest were detected in Blanice river). This indicates a lack of regulations and potential difficulties in effectively removing these substances from water with...
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Distribuce vybraných léčiv mezi články potravního řetězce ve vodním prostředí
LEXOVÁ, Veronika
This bachelor thesis deals with occurrence of pharmaceuticals in aquatic organisms. Sources of pharmaceuticals in recipients are treated effluents from sewage treatment plants. The mostly found in surface water and aquatic organisms are antibiotics, psychoactive pharmaceuticals, antihistamines, painkillers and cardiovascular pharmaceuticals. The occurrence of 20 selected pharmaceuticals at 10 localities affected by treated effluents from sewage treatment plants was studied in several types of matrices, in juvenile fish, plasma and muscle of adult common chub (Squalius cephalus), zebra mussel (Dreissena polymorpha) and benthic organisms. Based on the results, the highest concentrations of pharmaceuticals were found in benthic organisms and zebra mussels. The highest number of pharmaceuticals was found in benthic organisms (18 of 20 analysed) and 3 pharmaceuticals were found at all localities. The lowest number of pharmaceuticals was found in plasma and muscle of adult fish. Bílina Ústí nad Labem and Svratka Židlochovice belong to the most polluted localities. These rivers have low flows and treated wastewater from sewage treatment plants are less diluted therefore the concentration of pharmaceuticals in aquatic organisms is higher.
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Toxicita vybraných antiarytmik (verapamilu a diltiazemu) pro vodní organismy \kur{(Dpahnia magna)}
DOKOUPILOVÁ, Eliška
This bachelor thesis deals with a group of antiarrhythmic drugs and their toxicity to aquatic organisms. The theoretical part of the thesis summarizes the basic characteristics and distribution of antiarrhythmics, their mechanism of action and therapeutic use in the treatment of cardiovascular diseases together with their occurrence in the aquatic environment. Toxicology testing and related adverse effects of drugs on aquatic organisms are also described. The experimental part presents the results from a 21 day chronic toxicity test of verapamil and its degradation products on number of juveniles, number of broods and the body size of cladoceran Daphnia magna.
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An acidification of fresh waters is not over
Beneš, Filip ; Tátosová, Jolana (advisor) ; Hardekopf, David (referee)
Acidification of freshwaters is a problem of many areas over the northern hemisphere from the half of the 20th century. It has been caused by industrial factories discharging emissions of sulfur and nitrogen oxides, from which originate acids by the photochemical reactions in the atmosphere. Acidic atmospheric deposition has caused disappearance of fish and the most aquatic organisms in streams and lakes. Acidic atmospheric deposition has also washed up not only the buffering basic cations (Ca2+ , Mg2+ , Na+ , K+ ), but also toxic aluminium (Al3+ ) ions from soils into the freshwaters. The maximum levels of emissions of sulfur and nitrogen oxides were observed in 1980s and since that time the emissions of sulfur and nitrogen oxides significantly dropped down. However, the recovery from acidification is not as fast as it could be expected. It is impeding by several processes. One of them is hysteresis or saturation of soils by sulfur and nitrogen, which are slowly washing up into the freshwaters in forms of sulfates and nitrates now. Another process is the oligotrophication of lakes, when the important nutrient - phosphorus - is precipitating by aluminium. There is the lack of food for organisms after that. Another processes slowing down the recovery from acidification could be bad forest management...
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