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Novel perfluorinated compounds in the environment
Leifertová, Karolína ; Cajthaml, Tomáš (advisor) ; Innemanová, Petra (referee)
Perfluorinated compounds are a broad class of manmade chemicals. Even though they have been linked to hepatotoxicity, neurotoxicity, nephrotoxicity and carcinogenicity, the mechanism of toxicity still remains unclear. Only recently, two compounds (perfluorooctanesulfonic acid and perfluorooctanoic acid) have been phased out. This has led to a production of so-called "novel perfluorinated compounds". This work focuses on the evaluation of toxicity for 4 perfluorinated compounds, including the novel perfluorinated compounds (perfluorooctanesulfonic acid PFOS, perfluorooctanoic acid PFOA, hexafluoropropylene oxide dimer acid GenX, and hexafluoropropylene oxide trimer acid HFPO-TA). Gonadal and liver cell lines of rainbow trout were used for testing. Relevant toxicity tests were performed, such as viability tests (carboxyfluorescein diacetate, alamar blue and neutral red uptake), cytochrome P450 1A activation (ethoxyresorufin-o-deethylase, EROD) and measurements of reactive oxygen species generation (2',7'-dichlorofluorescein diacetate). HFPO- TA dramatically reduced viability and resulted in a statistically significant increase in intracellular reactive oxygen species. GenX caused an increase in EROD activity, but no effect on viability or reactive oxygen species formation was observed. The...
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Nové postupy biomonitoringu cizorodých látek ve vodním prostředí
ČERVENÝ, Daniel
Within the presented work, several approaches of biomonitoring were studied. A well-established method for human health risk assessment was applied to evaluate the quality of fish from open waters in the Czech Republic. As this work is targeted on sport fishermen, who frequently consume their own catches, besides the publication in scientific journal, a brochure with results of this study was distributed via the Czech Fishing Union. Health risks for consumers related to the consumption of wild fish were found strongly species and locality dependent. As there is no risks related with the consumption of carp (Cyprinus carpio) at all investigated sites, frequent consumption of predatory fish should be avoided at some fishing grounds. The use of passive samplers has become more and more attractive in the last two decades. As these devices are able to mimic the biological uptake of chemicals, their potential for replacing fish as bioindicators in routine biomonitoring programmes is evident. In our study, the comparison between analysis of fish tissues and POCIS extracts from selected sampling sites confirms this idea about interchangeability of these indicators in the case of PFASs as target pollutants. Moreover, no metabolic transformation of contaminants present in water take place in passive samplers contrary to living organisms, thus these reflect the actual contamination at the locality more precisely. The use of passive samplers completely fulfils the internationally accepted principles of Replacement, Reduction, Refinement (the three R´s). Another promising approach using YOY fish as bioindicators was evaluated within the present study. Multispecies samples of YOY fish homogenate was found as a better indicator for wide range of pollutants than muscle tissue of adult fish within one species from the same locality. As all inner organs and tissues are presented in analysed samples, more target pollutants in higher concentrations are detected compared to the muscle of adults. Besides the higher sensitivity in pollutants detection and quantification, practical and economic benefits are of concern in the case of the YOY fish approach. The YOY fish approach also particularly fulfil the three R´s strategy, as sampling of this age group of fish has a smaller impact on the environment than the sampling of adults. In case of mercury, that was found as a limiting contaminant for the consumption of fish from open waters in the Czech Republic, a nonlethal method of finclips sampling can be used for the monitoring of this compound in aquatic environments. Besides the monitoring, our optimised method for the estimation of muscle tissue concentrations could be used for human health risk assessment as well. The difference between real muscle concentrations and concentrations estimated using our method differs less than 10% in most of the investigated localities. Benthic organisms are an important part of the food web in aquatic environments, but insufficient information about its contamination is available. In another study included in this thesis, first evidence about bioaccumulation of certain pharmaceuticals in benthic organisms was described. Although, pharmaceuticals are generally considered to be not accumulative in organisms, our study proved that certain pharmaceuticals have bioaccumulation potential. From this finding, it is evident that not only the concentrations of pharmaceutical dissolved in water but also the diet represents an important exposure pathway of contamination by these compounds for organisms (fish) inhabiting aquatic environments.
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