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Study of contamination of river sediments with platinum metals
Novotný, Matěj ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This work deals with the characteristics of platinum metals and problems related to their toxicity and mobility in the environment, especially in the aquatic environment. These metals are released into the environment due to the use of automotive catalysts. Their function is based on the catalytic properties of platinum metals. Because of the high temperatures, these metals can be oxidized in the catalyst and subsequently emitted together with the combustion products into the surrounding atmosphere. The aim of the thesis is to measure real samples of river sediments of the river Svratka on the territory of the city of Brno and to find the possibility of contamination of the aquatic environment with these metals.
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Behavioral changes in fish after methamphetamine exposure
SLIVONĚ, Miroslav
Illegal drug use has adverse consequences in the global society, but what about other organisms or ecosystem? According to the results of recently published studies, the use of illegal drugs also has a negative effect on organisms in the aquatic environment, where it enters via insufficiently treated wastewater. This diploma thesis is focused on the effect of the illegal drug methamphetamine (METH) on the change in the behaviour of brown trout (Salmo trutta morpha fario) at environmentally relevant concentrations (1000 ng/L). The results of the experiments confirmed the presence of METH and its major metabolite amphetamine (AMFA) in the liver and brain tissue of exposed fish. The changes in fish behaviour suggest that exposure to METH affected the spatial orientation of fish, expressed by left laterality, and the locomotion, represented by higher exploratory activity of exposed fish. However, the effect of METH has not been demonstrated in the presence of fish near the feed site. Based on the results of this laboratory study, the negative impact of METH and its metabolites on individuals, populations, communities, and possibly entire ecosystems was concluded.
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Psychoaktivní sloučeniny ve vodním prostředí a jejich účinky na ryby
SANCHO SANTOS, Maria Eugenia
Psychoactive substances are emerging compounds that have received an increasing interest in ecotoxicology as a result of their ubiquitous presence in the environment, and the possible effects over non-targeted fauna. They have been detected in continental waters at concentrations ranging from nanograms to micrograms per litre, mainly as a consequence of the ineffective removal in the sewage treatment plants. Within this group of substances, methamphetamine and tramadol were selected in this dissertation due to the lack of research about their potential effects despite of the high amounts reported in water. Methamphetamine, mainly consumed as an illicit drug, is an addictive psychostimulant with special relevance in Central Europe. Environmental relevant and higher concentrations of methamphetamine in water leaded to histopathological alterations in heart and liver in brown trout (Salmo trutta m. fario). The major changes in heart were microvascular injuries, infiltration and fibrosis; and cytoplasmatic vacuolation of hepatocytes in liver. In addition, apoptotic changes were observed in liver. The findings were very similar to those reported in human and experimental animals. The parent compound and the main metabolite, amphetamine, were detected in trout tissues following the order kidney > liver > brain > muscle > plasma. The concentrations of the metabolite were evidently higher comparing to the parent compound; therefore, the histological findings could be suspected to partially derivate from amphetamine. Behaviour - i.e. activity and place preference - and metabolome changes for the period of withdrawal were observed in trouts, linked to remnants of the parent compound and the metabolite in brain. Tramadol is an extensively used analgesic which singular mode of action provides added antidepressant and anxiolytic effects. Realistic concentration of tramadol in water was found to impair essential behavioural traits in the chub (Squalius cephalus) - a native fish species in Central Europe. The degree of the outcomes was correlated with the individual amounts of tramadol in brain. Exposed fish exhibited anxiolytic-like effects, illustrated by lesser bold and social individuals comparing to controls. In the boldness test, exposed fish were less frequently out of the shelter and moved a shorter distance, therefore, they explored the new environment less than control fish. The novel object recognition experiment indicated that, although they distinguished the new item, their activity was reduced, and they explored the new object less. The increased interindividual distance indicated that the shoal cohesion was disturbed. The behavioural traits were associated to the treatment, suggesting the influence of the pollutant over fish personality. Bioconcentration factors for tramadol and methamphetamine were low in all cases, thus, the probability of bioconcentration for these substances is very low. However, these compounds are continuously released into water, leading to their pseudo-persistence and the consequent presence in tissues. The occurrence in fish, and the parallelism in the target signalization result in similar actions in these organisms comparing to human and experimental models. Here we evidenced that the water pollution with the tested neuroactive substances in the aquatic compartment could lead to unexpected effects over fauna, and subsequent changes in the whole aquatic ecosystem.
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Study of contamination of river sediments with platinum metals
Novotný, Matěj ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This work deals with the characteristics of platinum metals and problems related to their toxicity and mobility in the environment, especially in the aquatic environment. These metals are released into the environment due to the use of automotive catalysts. Their function is based on the catalytic properties of platinum metals. Because of the high temperatures, these metals can be oxidized in the catalyst and subsequently emitted together with the combustion products into the surrounding atmosphere. The aim of the thesis is to measure real samples of river sediments of the river Svratka on the territory of the city of Brno and to find the possibility of contamination of the aquatic environment with these metals.
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Vliv chemikálií přítomných ve výtocích z čistíren odpadních vod na ryby
GRABICOVÁ, Kateřina
There are many compounds that are used or produced by humans, e.g. pharmaceuticals and personal care products (PPCPs) which are used in large quantities around the world. These compounds end up in waste waters and enter sewage treatment plants (STPs). But not all of these compounds are removed during the treatment processes in STP and they enter the aquatic environment via sewage effluents. The thesis is focused especially on evaluation of presence and potential toxicological effects of PPCPs in aquatic environment. The risk assessment for a single compound is usually based on laboratory experiments. The first tested compound was verapamil, a pharmaceutical for lowering blood pressure and treatment of cardiac diseases. Two types of tests were carried out, an acute one with high concentration levels and a sub-chronic one with levels that included environmentally relevant concentration. After the exposure, common carp larvae and embryos showed malformation and edemas and the heart rate was decreased. According to 96hLC50, the verapamil could be classified as a harmful or toxic substance. The second tested substance was UV filter 2 phenylbenzimidazole-5-sulfonic acid which was found at relatively high concentrations in south Bohemian surface waters. In spite of very low bioconcentration of PBSA in fish, activities of 7-ethoxyresorufin-O-deethylase, 7-methoxyresorufin-O-deethylase and 7-penthoxyresorufin-O-deethylase in exposed rainbow trout were increased which indicate that activity of cytochromes P450 were affected even in environmentally relevant concentration. In a real aquatic system, fish are exposed to waters which contain not only a single pollutant but a mixture of them. A consequent experiment was carried out on rainbow trout caged in effluent for 13 days from STP in Gothenburg, the second biggest STP in Sweden. The concentration of selected antidepressants was measured in different fish tissues and plasma. Citalopram, sertraline and venlafaxine were found in fish brain and liver. As these antidepressants are used for the treatment of psychical disorders, behavior of fish could be affected. The limitations of these experiments, even with real water with a mixture of chemicals, are that fish are stressed in aquaria or cages and the exposure via the food chain is not included. Benthic organisms are an important part of fish diet. The impact of pollution on benthic organisms is often studied. However, there is limited knowledge about the bioaccumulation of pharmaceuticals in the benthos and consequently in fish. Therefore bioaccumulation in Hydropsyche and Erpobdella was studied. These organisms were collected in non-polluted and in effluent affected localities. Antibiotics azithromycin and clarithromycin, cardio-vascular drug verapamil, antifungal drug clotrimazole and antidepressants citalopram and sertraline were found in Hydropsyche. Cardio-vascular drug valsartan, antidepressant sertraline, anti-inflammatory drug diclofenac and antifungal drug clotrimazole were found in Erpobdella. Passive sampling is an integrative sampling method which allows the obtaining of time average concentration over period of few weeks. POCIS (Polar Organic Chemical Integrative Samplers) are used for sampling of polar compounds. It also can mimic bioconcentration. Based on the field experiments, the sampling rate for individual pharmaceuticals and illicit drugs was calculated. Twenty-one localities in the Czech Republic were sampled by POCIS and the water concentration of psychoactive drugs was estimated. Further research is necessary to make POCIS passive sampling a more precise tool for monitoring pharmaceutical and drug contents in aquatic environments.
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Farmaka ve vodním prostředí a jejich vliv na ryby
BURKINA, Viktoriia
In this thesis, the impact of atenolol, verapamil, dexamethasone, clotrimazole, and PBSA on the physiological condition and health of rainbow trout (Oncorhynchus mykiss) were studied in vivo and in vitro. The sub-chronic test of atenolol, including at the environmentally relevant concentration, demonstrated that only the fish exposed to atenolol at a concentration of 1000 ?g?L-1 may be at a higher risk of oxidative stress. The second pharmaceutical compound studied was an L-type calcium channel blocker, verapamil. Despite the relatively high concentration of verapamil included in the experiments, the rates of seven hepatic CYP450-mediated reactions (EROD, MROD, PROD, BFCOD, COH, and PNPH) were unchanged in the exposed rainbow trout. This indicates that the activities of the selected CYP450 enzymes were not affected. Exposure to the highest concentration of PBSA (1000 ?g?L-1) led to significantly inhibited glutathione reductase activity. The activities of the EROD, MROD, and PROD enzymes gradually increased, beginning at the environmentally relevant concentrations. We suggest that long-term exposure to PBSA could cause oxidative stress in fish, as indicated by the decreased activity of GR. Moreover, PBSA could interact with intracellular receptors due to the elevated activities of CYP1A (EROD and MROD) and CYP2B (PROD). Rainbow trout showed multiple responses after exposure to clotrimazole. Changes in the haematological parameters in the exposed rainbow trout suggested that the immune system and haemoglobin synthesis were affected. The antioxidant defence enzymes that responded to the clotrimazole exposure influenced the oxidative stress status of the fish. Sub-chronic exposure to clotrimazole did not lead to oxidative stress in any of the fish tissues studied, as indicated by the unchanged TBARS levels. Hepatic energetic pathways were activated in the tested groups after 42 days of exposure to clotrimazole. High levels of glutathione S-transferase were seen in the liver and gill tissues, possibly associated with the detoxification of clotrimazole. The interaction of clotrimazole with intracellular receptors can be expected due to the changes in the catalytic activities of CYP1A1 and CYP3A. The BCF levels in the muscle tissue suggest a moderate bioaccumulation of CLO. The relatively long elimination period for CLO in the fish kidney (half-life = 29 days) may imply a greater potential for adverse effects in this organ. This finding is significant in view of the structural disturbances that appeared in the kidney and testis. The changes observed in the kidney were most prominent in the tubular epithelial cells. Changes in the gonads were only visible in the male specimens, and the pathological changes in the testis may indicate a disruption of steroidogenesis. The potential of clotrimazole and dexamethasone to inhibit CYP450 enzyme activity in rainbow trout hepatic microsomes was investigated in vitro. Clotrimazole non-competitively inhibited EROD activity in the hepatic microsomes, while BFCOD activity was competitively inhibited. PNPH activity was only slightly reduced in the presence of clotrimazole, indicating that it does not significantly interact with CYP2E1. The presence of dexamethasone in the incubations did not affect any of the CYP450 enzymes investigated. Everything considered, the results of the study confirmed that the presence of clotrimazole in the environment is of concern with respect to its impact on the health status of fish. In this thesis, the data of the actual effects of several PPCPs on fish were discussed. Based on the response of selected molecular endpoints, the cardiovascular and anti-inflammatory drugs studied do not present a significant risk for fish, while the antifungal drug and UV-screening agent that were tested may disrupt several physiological processes in fish.
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