Monika Załęska-Radziwiłł

The impacts of aluminum and zirconium nano-oxides on planktonic and biofilm bacteria

AbstractNanoparticles are molecules, whose dimensions are below 100 nm; they are of colloidal particle size and are often smaller than eukaryotic cells and bacteria. Their increasingly common application might cause their release into sewage and the induction of toxic reactions, among others, in micro-organisms participating in wastewater treatment. The aim of this study was to compare the ecotoxicity of commercial nanoparticles of aluminum oxides and zirconium oxides, in relation to two bacterial strains Pseudomonas putida and Aeromonas hydrophila. These bacteria have an ability to form biofilms, as they are present in planktons and participate in wastewater treatment. The study also includes the assessment of aluminum oxide (Al2O3) and zirconium oxides’ (ZrO2) ecotoxicity in order to compare their harmfulness with the nanoparticular form. It has been found that aluminum and zirconium nano-oxides were more harmful to bacteria compared to aluminum and zirconium oxides. Biofilm-forming bacteria were more r...

Application of white-rot fungi for biodegradation of refractory organic compounds—a review

AbstractThe article presents an overview of literary sources on the use of fungi that cause white rot for removal of organic pollutants from water, wastewater and wastewater sludge. The study characterizes enzymes produced by these fungi, and the methods and conditions for their culture. The article includes some examples of the use of fungi for treatment of wastewater from paper, textile, alcohol and food production, among others, and for biodegradation of dyes, hydrocarbons, phenols, chlorophenols, nitrotoluen and pesticides. It discusses some technological parameters of devices used for elimination of pollutants from wastewater with the use of white-rot fungi. The article highlights the need to extend research work from lab scale to semi-technical scale.

Ecotoxicity of chosen pharmaceuticals in relation to micro-organisms—risk assessment

ABSTRACTThe aim of this study is to assess the impact of three pharmaceutical substances from the group of antibacterial drugs (ciprofloxacin), estrogens (17α-ethinylestradiol) and cytostatic drugs (5-fluorouracil) on micro-organisms. Enzymatic tests (bioluminescence tests with Vibrio fischeri, dehydrogenase and hydrolytic activity of activated sludge organisms) and growth tests (with Pseudomonas fluorescens and microbial assay for toxic risk assessment with 10 species of bacteria and 1 species of fungi) were performed. The obtained values of concentrations of EC50-t and NOEC showed a different sensitivity of the organisms to the examined active substances. According to the EU criteria, ciprofloxacin was extremely toxic and very toxic to nine species and toxic to three species of bacteria. 17α-ethinylestradiol was extremely toxic and toxic to five species and also harmful to five species. 5-fluorouracil proved to be extremely toxic to seven micro-organisms and very toxic and toxic to five. All active ingr...

In vitro and in vivo genotoxicity assessment of selected pharmaceuticals in relation to Escherichia coli and Cyprinus carpio.

ABSTRACT Genotoxicity studies (using SOS chromotest and comet assay) of Escherichia coli and carp (Cyprinus carpio) were performed for three pharmaceutically active compounds, ciprofloxacin, 17α-ethinylestradiol and 5-fluorouracil, used in the treatment of humans. The values of genotoxicity induction coefficient (I) in the SOS chromotest clearly showed genotoxicity for ciprofloxacin, both in the presence and in the absence of S9 fraction; 17α-ethinylestradiol demonstrated slight genotoxicity at the highest tested concentration; and 5-fluorouracil did not induce genotoxic effects in Escherichia coli mutants. Statistical analysis of the results of the comet assay revealed significant differences in cell populations derived from carp placed in a solution of 5-fluorouracil in comparison with the negative control. Statistical analysis also showed a significant increase of “% DNA in tail” of comets in cell populations incubated in solutions of 17α-ethinylestradiol at concentrations of 10000, 2000 and 400 µg/L and in solutions of 5-fluorouracil with S9 fraction at concentrations of 50,000 and 2,000 μg/L in comparison with the negative controls.

Ecotoxicological risk assessment of chosen pharmaceuticals detected in surface waters

ABSTRACT The goal of this work was to assess the risk posed by the presence of ciprofloxacin, 17α-ethinylestradiol and 5-fluorouracil in aquatic ecosystems based on chronic single-species ecotoxicological tests. There were 23 species used in this study: one cyanobacterium, three green algae, one higher plant, one protozoan, two crustaceans, two fish, 12 bacteria and one fungus (yeast). The risk assessment was performed on the basis of the PEC/PNEC ratio (PEC – predicted environmental concentration, PNEC – predicted no-effect concentration). PNEC was calculated using an assessment factor and statistical extrapolation models. The risk in relation to aquatic organisms proved to be high. The potentially affected fraction of aquatic species in the presence of pharmaceutical active ingredients, depending on the calculation method and the selected concentration in surface waters (predicted or measured), ranged from 6.26 to 27.84% for ciprofloxacin, 2.13 to 18.74% for 17α-ethinylestradiol and 4.96 to 39.28% for 5-fluorouracil. The study indicates several gaps in the existing guidelines, which may be considered within the guideline-revision process.

Ecotoxicity of ionic liquids as lubricants

In this article there is discussed a possibility of forming the liquid crystal structure in ionic liquids and its influence on performance characteristics, especially tribological, of these liquids. Formation of such thermal phase might influence on, among other things, easier creation of the boundary lubricating film, which is characterized by high viscous anisotropy. The results of tribological tests showed better lubricity of selected ionic liquids than modern PFPE oils. Identification of mesophase in ionic liquids was necessary. This method is described in the paper. Biolar PL polarizing interference microscope with thermal stabilizing table, with birefraction system, and Brüker Discover 8 powder diffraction instrument with a Cu lamp and monochromator were used. There was being searched the state characterized simultaneously by optical anisotropy properties and liquid state of aggregation. For identification of phase transition temperature, the additional calorimetric tests were carried out during the cycle of heating and cooling. These researches were carried out within the framework of the development and research project no. PBR 15-249/2007/WAT-OR0002904, financed by Ministry of Science and Higher Education during 2007-2011.