TY - JOUR AB - In this study a comparative assessment using various advanced oxidation processes (UV/H2O2, UV/H2O2/Fe(II), O3, O3/UV, O3/UV/H2O2 and O3/UV/H2O2/Fe(II)) was attempted to degrade efficiently two fluoroquinolone drugs ENR [enrofloxacin (1-Cyclopropyl-7-(4-ethyl-1-piperazinyl)-6-fluoro-1,4-dihydro-4-oxo-3-quinolonecarboxylic acid)] and CIP [ciprofloxacin (1-cyclopropyl-6-fluoro-4-oxo-7-(piperazin-1-yl)-quinoline-3-carboxylic acid)] in aqueous solutions at a concentrations of 0.15 mM for each drug. The efficiency of the applied oxidation processes (AOPs) has been estimated by the conversion of the original substrate (XENR and XCIP) and the reduction of chemical oxygen demand (COD), total organic carbon (TOC). Special emphasis was laid on the effect of varying reaction pH as well as of the applied oxidant doses on the observed reaction kinetics for each advanced oxidation processes. High degradation efficiencies, particularly in terms of rates of TOC and COD abatement, were obtained for photo-Fenton assisted ozonation [O3/UV/H2O2/Fe(II)], compared to other advanced oxidation processes. At pH 3 and 25 degrees C best results for the degradation of both investigated drugs were achieved when 10 mM H2O2, 0.5 mM Fe(II) and an initial dose of 8.5 mg L-1 ozone were applied. In addition, the evolution of toxicity of the reaction mixtures for different AOPs has been studied by the bioluminescence test (LUMIStox 300). AU - Bobu, M. AU - Yediler, A. AU - Siminiceanu, I.* AU - Zhang, F.F.* AU - Schulte-Hostede, S. C1 - 11757 C2 - 30812 SP - 251-262 TI - Comparison of different advanced oxidation processes for the degradation of two fluoroquinolone antibiotics in aqueous solutions. JO - J. Environ. Sci. Health A Tox. Hazard. Subst. Environ. Eng. VL - 48 IS - 3 PB - Taylor & Francis PY - 2013 SN - 1093-4529 ER - TY - JOUR AB - The degradation of a paracetamol (N-acetil-para-aminofenol) aqueous solution (C-0 (P) = 5mmol L-1) is studied in a bench-scale setup by means of simple ozonation (O-3) and ozonation catalyzed with UV light (O-3/UV) in order to quantify the influence of UV light on the degradation process. The results have shown that under the adopted experimental conditions (25 degrees C, applied ozone dose = 9.8mg L-1 and gas flow rate of 20 L h(1)) both oxidative systems are capable of removing the substrate with mineralization degrees up to 51% for ozonation and 53% for O-3/UV. HPICE chromatography allowed the detection of nitrate ions and maleic and oxalic acids as ultimate carboxylic acids. The experimental data have been interpreted through 5 indicators: the conversion of paracetamol (X-P ), the conversion degree of TOC (X-TOC ), the apparent rate constant (k(ap) ), the Hatta number (Ha) and the enhancement factor (E). The main advantage of photo-ozonation compared to simple ozonation was a more advanced conversion (79% vs. 92% after 90min). The paracetamol decay follows a pseudofirst-order reaction with a superior rate constant (higher by 54%) for the UV catalyzed system in comparison with direct ozonation. Mineralization is slightly accelerated (+4%) in the O-3/UV system, due to the additional production of hydroxyl radicals induced by the UV light and a higher Hatta number (+24%). Nevertheless, the process was still in the slow reaction kinetic regime (Ha < 0.3), and the enhancement factor was not significantly increased. The results are useful for the design and scale-up of the gas-liquid processes. AU - Neamtu, M.* AU - Bobu, M.* AU - Kettrup, A. AU - Siminiceanu, I.* C1 - 24716 C2 - 31657 SP - 1264-1271 TI - Ozone photolysis of paracetamol in aqueous solution. JO - J. Environ. Sci. Health A Tox. Hazard. Subst. Environ. Eng. VL - 48 IS - 10 PB - Taylor & Francis PY - 2013 SN - 1093-4529 ER - TY - JOUR AB - Titanium dioxide (TiO2) nanoparticles have a high surface-to-mass ratio and rapidly aggregate in water causing great difficulties for toxicity test exposed to aquatic organisms or other cell lines. This study uses a cell viability kit for routine toxicity test of TiO2 as well as other nanoparticles which accumulate in the aquatic environment. Tetrahymena immediately endocytoses TiO2 nanoparticles and stores them in food vacuoles until the particles undergo exocytosis as larger aggregates. However, during the process of endocytosis and exocytosis, TiO2 particles interfere with cell growth and consequently induce acute toxicity. It exerted high cell growth inhibition at 20h incubation and induces significant cytotoxic effects. Surprisingly, the effect of TiO2 decreases at 40h incubation, due to the recovery of cell growth and reduction of the cytotoxicity of the particles. AU - Ud-Daula, A. AU - Pfister, G. AU - Schramm, K.-W. C1 - 24575 C2 - 31586 SP - 1343-1348 TI - Method for toxicity test of titanium dioxide nanoparticles in ciliate protozoan Tetrahymena. JO - J. Environ. Sci. Health A Tox. Hazard. Subst. Environ. Eng. VL - 48 IS - 11 PB - Taylor & Francis PY - 2013 SN - 1093-4529 ER - TY - JOUR AB - In this study, Mediterranean mussel species, Mytilus galloprovincialis, were exposed to phenanthrene (PHE) due to its ubiquitousness and bioavailability in the aquatic environment. Kinetic parameters of the PHE bioaccumulation and depuration were calculated for an 11-day uptake and subsequent 11-day depuration periods. Those values of kinetic rate constants for uptake and depuration of PHE were calculated as varying between 93177 and 0.180.25, respectively. Negative correlation was observed between the PHE concentrations and kinetic rate constants. Bioaccumulation Factors (BAFs) for the mussels exposed to different PHE concentrations were calculated from both kinetic rate constants and from the experimental data and found between 509701 and 441658, respectively. Experimental quantitative structure activity relationship (QSAR) values for PHE were found comparable to the calculated QSARs reported in literature. Two sub-lethal biomarker methods (filtration rate and lysosomal stability) were applied to observe the responses of the mussels throughout the experimental period. Results of both biomarkers show that PHE negatively affects mussels during the uptake of PHE, and mussels were able to recover physiologically at the end of depuration period according to the filtration rate results. AU - Yakan, S.D.* AU - Henkelmann, B. AU - Schramm, K.-W. AU - Okay, O.S.* C1 - 24439 C2 - 31559 SP - 1037-1046 TI - Bioaccumulation-depuration kinetics and effects of phenanthrene on Mediterranean mussel (Mytilus galloprovincialis). JO - J. Environ. Sci. Health A Tox. Hazard. Subst. Environ. Eng. VL - 48 IS - 9 PB - Taylor & Francis PY - 2013 SN - 1093-4529 ER - TY - JOUR AB - Surface sediments from 12 different locations of the Istanbul Strait and Marmara Sea, Turkey were analysed for five antibiotics belonging to two different groups of widely used pharmaceuticals, tetracyclines (TCs) and fluoroquinolones (FQs), by solid-phase extraction and high performance liquid chromatography. These two groups of antibiotics, mainly used to prevent or treat illness for humans as well as for animals, are frequently detected in the effluent of municipal sewage plants, in the aquatic environments and in soils after being spread by liquid manure. The results of analysis revealed that measured concentrations of individual antibiotics were significantly different depending on sampling location. Chlortetracycline (CTC) was not detected in any of the samples. High concentrations were mainly found in urbanized regions of the Strait. The concentrations of the two tetracyclines ranged from not detectable to 27.3 mu g kg(-1) in freeze-dried marine sediments. Comparable results were obtained for the two fluoroquinolones with concentration levels from 1.3 mu g kg(-1) up 34.1 mu g kg(-1). This study is the first attempt to show the contamination degree of the Istanbul Strait sediments by emerging contaminants. Particular concern should be given concerning their potential side effects caused by the frequent consumption of mussels and fishes captured in the Istanbul Strait. AU - Okay, O.S.* AU - Li, K.X.* AU - Yediler, A. AU - Karacik, B.* C1 - 7539 C2 - 29811 SP - 1372-1380 TI - Determination of selected antibiotics in the Istanbul strait sediments by solid-phase extraction and high performance liquid chromatography. JO - J. Environ. Sci. Health A Tox. Hazard. Subst. Environ. Eng. VL - 47 IS - 10 PB - Taylor & Francis PY - 2012 SN - 1093-4529 ER - TY - JOUR AB - A 96-well plate culture methodology for the unicellular eukaryote Tetrahymena pyriformis, strain GL was used for the determination of toxicity and metabolism of catecholamines. Catecholamines exhibited moderate acute toxicity to Tetrahymena cells where dopamine and L-DOPA showed higher toxic potential at EC10 (0.39 ppm and 0.63 ppm, respectively) and EC20 (1.1 ppm and 1.0 ppm respectively) after 48 h exposure. All tested catecholamines were highly degradable in the PPY-medium due to the oxidizing environment during incubation. Also the catecholamines were naturally synthesized and released by Tetrahymena cells into the culture medium and increasingly accumulated with time where noradrenalin exhibited the highest degree of accumulation. However, the exogenous exposure of catecholamines to the cells caused the depletion of natural noradrenalin synthesis even with the addition of very low physiological concentration (0.12 ppm). Dopamine caused the higher effect on inhibiting noradrenalin synthesis. Treatment with a higher concentration (8.0 ppm) of dopamine in 96-well plates caused strong excitation of the cells and ascertained a new metabolite in vivo while the other representative catecholamines were not responsible for the production of this metabolite. This dopamine metabolite is relatively non-polar as compared to noradrenalin, adrenaline and dopamine and eluting later through the reverse phase C-18 column. AU - Ud-Daula, A. AU - Pfister, G. AU - Schramm, K.-W. C1 - 2521 C2 - 25844 SP - 1610-1617 TI - Growth inhibition and biodegradation of catecholamines in the ciliated protozoan Tetrahymena pyriformis. JO - J. Environ. Sci. Health A Tox. Hazard. Subst. Environ. Eng. VL - 43 IS - 14 PB - Dekker PY - 2008 SN - 1093-4529 ER - TY - JOUR AB - The combination of chemical and biological water treatment processes is a promising technique to reduce recalcitrant wastewater loads. The key to the efficiency of such a system is a better understanding of the mechanisms involved during the degradation processes. Ozonation has been applied to many fields in water and wastewater treatment. Especially for effluents of textile finishing industry ozonation can achieve high color removal, enhance biodegradability, destroy phenols and reduce the COD. However, little is known about the reaction intermediates and products formed during ozonation. This work focuses on the oxidative degradation of purified (>90%), hydrolyzed Reactive Red 120 (Color Index), a widely used azo dye in the textile finishing processes with two monochlorotriazine anchor groups. Ozonation of the dye in ultra pure water was performed in a laboratory scale cylindrical batch reactor. Decolorization, determined by measuring the light absorbance at the maximum wavelength in the visible range (53 5 nm), was almost complete after 150 min with an ozone concentration of 12.8 mg/l. The TOC/TOC0 ratio was about 74% and the COD was diminished to 46% of the initial value. The BOD5/COD ratio increased from 0.01 to 0.14. To obtain detailed information on the reaction processes during ozonation and the resulting oxidation products organic and inorganic anions were analyzed. Oxidation and cleavage of the azo group yielded nitrate. Cleavage of the sulfonic acid groups of aromatic rings caused an increase in the amount of sulfate. Formic acid and oxalic acid were identified as main oxidation products by high performance ion chromatography (HPIC). The concentrations of these major products were monitored at defined time intervals during ozonation. AU - Zhang, F.* AU - Yediler, A. AU - Liang, X.* AU - Kettrup, A. C1 - 10085 C2 - 20190 SP - 707-713 TI - Ozonation of the Purified Hydrolyzed Azo Dye Reactive Red 120 (CI). JO - J. Environ. Sci. Health A Tox. Hazard. Subst. Environ. Eng. VL - A37 PB - Dekker PY - 2002 SN - 1093-4529 ER - TY - JOUR AU - Takenaka, S. AU - Fürst, G. AU - Heilmann, P. AU - Heini, A. AU - Hillebrecht, A. AU - Murray, A.B. AU - Heyder, J. C1 - 19091 C2 - 12146 SP - 187-202 TI - An Approach to unbiased sampling of Pulmary Structures for Morphometric Analysis. JO - J. Environ. Sci. Health A Tox. Hazard. Subst. Environ. Eng. VL - 28 PY - 1993 SN - 1093-4529 ER -