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Olive Gans - One of the best experts on this subject based on the ideXlab platform.
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methodological approach towards the environmental significance of uncharacterized substances Quaternary Ammonium Compounds as an example
Desalination, 2007Co-Authors: Norbe Kreuzinge, Sigrid Scharf, Olive Gans, Maria Fuerhacke, Maria Uhl, Itta GrillitschAbstract:Abstract The European Commission has presented a list of priority substances in addition to the Water Framework Directive (WFD) adopted in December 2000. The list of priority substances is a matter of continuous review hence other relevant substances identified as hazardous can be implemented for regulation. In that regard a group of potential hazardous substances, Quaternary Ammonium Compounds (QAC) is selected for further investigation and assessment, as QAC are widely used as disinfectants, biocides, and detergents among a variety of other applications. This paper provides information on a general interdisciplinary approach for assessing the potential significance of chemical substances hitherto not described in a coherent way considering QACs as example. Benzalkonium chlorides (BAC) and dialkyldimethylAmmonium chlorides (DDAC) were selected as key Compounds because of their product and application profiles, as well as their ecotoxicological properties. For basic environmental risk evaluation, QAC usage pattern, emissions from single source polluters, the fate in waste water treatment plants, concentrations in surface water and sediments, as well as ecotoxicological effective concentrations were analyzed in this study. Based on substrate characteristics and use pattern relevant single source polluters were identified and emission concentrations as well as loads discharged into the sewerage were determined. Effluents from hospitals and laundries but also from wellness resorts showed high effluent concentrations compared to municipal waste water. To describe the fate of QACs during waste water treatment, adsorption and degradation behavior were determined. Additionally the influence of QACs on biological processes, especially nitrification was assessed. Partition coefficient values (log kOC) for QACs were determined between 4.35 for DDAC-C10 and 5.69 for DDAC-C18 (data not shown) indicating the high adsorption potential of those substances to the activated sludge in the waste water treatment plants. Results for BAC-C12–18 were found to be in the same range. Concentrations for nitrification inhibition in waste water treatment plants lay above concentrations found in municipal waste water but in the range of concentrations discharged by single source polluters.
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determination of selected Quaternary Ammonium Compounds by liquid chromatography with mass spectrometry part ii application to sediment and sludge samples in austria
Environmental Pollution, 2007Co-Authors: Elena Martinezcarballo, C Gonzalezbarreiro, Andrea Sitka, Norbe Kreuzinge, Sigrid Scharf, Olive GansAbstract:Abstract Soxhlet extraction and high-performance liquid chromatography (HPLC) coupled to tandem mass spectrometry detection (MS/MS) was used for the determination of selected Quaternary Ammonium Compounds (QACs) in solid samples. The method was applied for the determination of alkyl benzyl, dialkyl and trialkyl Quaternary Ammonium Compounds in sediment and sludge samples in Austria. The overall method quantification limits range from 0.6 to 3 μg/kg for sediments and from 2 to 5 μg/kg for sewage sludges. Mean recoveries between 67% and 95% are achieved. In general sediments were especially contaminated by C12 chain benzalkonium chloride (BAC-C12) as well as by the long C-chain dialkyldimethylAmmonium chloride (DDAC-C18) with a maximum concentration of 3.6 mg/kg and 2.1 mg/kg, respectively. Maxima of 27 mg/kg for DDAC-C10, 25 mg/kg for BAC-C12 and 23 mg/kg for BAC-C14 were determined for sludge samples. The sums of the 12 selected target Compounds range from 22 mg/kg to 103 mg/kg in the sludge samples.
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determination of selected Quaternary Ammonium Compounds by liquid chromatography with mass spectrometry part i application to surface waste and indirect discharge water samples in austria
Environmental Pollution, 2007Co-Authors: Elena Martinezcarballo, C Gonzalezbarreiro, Andrea Sitka, Norbe Kreuzinge, Sigrid Scharf, Maria Furhacke, Olive GansAbstract:Abstract A method for simultaneous quantitative determination of alkyl benzyl, dialkyl and trialkyl Quaternary Ammonium Compounds (QACs) has been developed, validated and subsequently applied to real water samples in Austria. The method employs liquid-liquid extraction (LLE) followed by liquid chromatography/tandem mass spectrometry (LC-MS/MS), using electrospray ionization (ESI) in positive mode. The overall method quantification limits range from 4 to 19 ng/L for the enrichment of 500 mL water samples and analyte recoveries are between 80 and 99%. The method was applied to 62 of the respective water samples without filtration to avoid the loss of the analytes due to the high adsorption capacity of these Compounds. Maxima in the mg/L range, especially in the wastewater of hospitals and laundries, could be detected for the selected target Compounds.
Norbe Kreuzinge - One of the best experts on this subject based on the ideXlab platform.
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methodological approach towards the environmental significance of uncharacterized substances Quaternary Ammonium Compounds as an example
Desalination, 2007Co-Authors: Norbe Kreuzinge, Sigrid Scharf, Olive Gans, Maria Fuerhacke, Maria Uhl, Itta GrillitschAbstract:Abstract The European Commission has presented a list of priority substances in addition to the Water Framework Directive (WFD) adopted in December 2000. The list of priority substances is a matter of continuous review hence other relevant substances identified as hazardous can be implemented for regulation. In that regard a group of potential hazardous substances, Quaternary Ammonium Compounds (QAC) is selected for further investigation and assessment, as QAC are widely used as disinfectants, biocides, and detergents among a variety of other applications. This paper provides information on a general interdisciplinary approach for assessing the potential significance of chemical substances hitherto not described in a coherent way considering QACs as example. Benzalkonium chlorides (BAC) and dialkyldimethylAmmonium chlorides (DDAC) were selected as key Compounds because of their product and application profiles, as well as their ecotoxicological properties. For basic environmental risk evaluation, QAC usage pattern, emissions from single source polluters, the fate in waste water treatment plants, concentrations in surface water and sediments, as well as ecotoxicological effective concentrations were analyzed in this study. Based on substrate characteristics and use pattern relevant single source polluters were identified and emission concentrations as well as loads discharged into the sewerage were determined. Effluents from hospitals and laundries but also from wellness resorts showed high effluent concentrations compared to municipal waste water. To describe the fate of QACs during waste water treatment, adsorption and degradation behavior were determined. Additionally the influence of QACs on biological processes, especially nitrification was assessed. Partition coefficient values (log kOC) for QACs were determined between 4.35 for DDAC-C10 and 5.69 for DDAC-C18 (data not shown) indicating the high adsorption potential of those substances to the activated sludge in the waste water treatment plants. Results for BAC-C12–18 were found to be in the same range. Concentrations for nitrification inhibition in waste water treatment plants lay above concentrations found in municipal waste water but in the range of concentrations discharged by single source polluters.
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determination of selected Quaternary Ammonium Compounds by liquid chromatography with mass spectrometry part ii application to sediment and sludge samples in austria
Environmental Pollution, 2007Co-Authors: Elena Martinezcarballo, C Gonzalezbarreiro, Andrea Sitka, Norbe Kreuzinge, Sigrid Scharf, Olive GansAbstract:Abstract Soxhlet extraction and high-performance liquid chromatography (HPLC) coupled to tandem mass spectrometry detection (MS/MS) was used for the determination of selected Quaternary Ammonium Compounds (QACs) in solid samples. The method was applied for the determination of alkyl benzyl, dialkyl and trialkyl Quaternary Ammonium Compounds in sediment and sludge samples in Austria. The overall method quantification limits range from 0.6 to 3 μg/kg for sediments and from 2 to 5 μg/kg for sewage sludges. Mean recoveries between 67% and 95% are achieved. In general sediments were especially contaminated by C12 chain benzalkonium chloride (BAC-C12) as well as by the long C-chain dialkyldimethylAmmonium chloride (DDAC-C18) with a maximum concentration of 3.6 mg/kg and 2.1 mg/kg, respectively. Maxima of 27 mg/kg for DDAC-C10, 25 mg/kg for BAC-C12 and 23 mg/kg for BAC-C14 were determined for sludge samples. The sums of the 12 selected target Compounds range from 22 mg/kg to 103 mg/kg in the sludge samples.
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determination of selected Quaternary Ammonium Compounds by liquid chromatography with mass spectrometry part i application to surface waste and indirect discharge water samples in austria
Environmental Pollution, 2007Co-Authors: Elena Martinezcarballo, C Gonzalezbarreiro, Andrea Sitka, Norbe Kreuzinge, Sigrid Scharf, Maria Furhacke, Olive GansAbstract:Abstract A method for simultaneous quantitative determination of alkyl benzyl, dialkyl and trialkyl Quaternary Ammonium Compounds (QACs) has been developed, validated and subsequently applied to real water samples in Austria. The method employs liquid-liquid extraction (LLE) followed by liquid chromatography/tandem mass spectrometry (LC-MS/MS), using electrospray ionization (ESI) in positive mode. The overall method quantification limits range from 4 to 19 ng/L for the enrichment of 500 mL water samples and analyte recoveries are between 80 and 99%. The method was applied to 62 of the respective water samples without filtration to avoid the loss of the analytes due to the high adsorption capacity of these Compounds. Maxima in the mg/L range, especially in the wastewater of hospitals and laundries, could be detected for the selected target Compounds.
Sigrid Scharf - One of the best experts on this subject based on the ideXlab platform.
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methodological approach towards the environmental significance of uncharacterized substances Quaternary Ammonium Compounds as an example
Desalination, 2007Co-Authors: Norbe Kreuzinge, Sigrid Scharf, Olive Gans, Maria Fuerhacke, Maria Uhl, Itta GrillitschAbstract:Abstract The European Commission has presented a list of priority substances in addition to the Water Framework Directive (WFD) adopted in December 2000. The list of priority substances is a matter of continuous review hence other relevant substances identified as hazardous can be implemented for regulation. In that regard a group of potential hazardous substances, Quaternary Ammonium Compounds (QAC) is selected for further investigation and assessment, as QAC are widely used as disinfectants, biocides, and detergents among a variety of other applications. This paper provides information on a general interdisciplinary approach for assessing the potential significance of chemical substances hitherto not described in a coherent way considering QACs as example. Benzalkonium chlorides (BAC) and dialkyldimethylAmmonium chlorides (DDAC) were selected as key Compounds because of their product and application profiles, as well as their ecotoxicological properties. For basic environmental risk evaluation, QAC usage pattern, emissions from single source polluters, the fate in waste water treatment plants, concentrations in surface water and sediments, as well as ecotoxicological effective concentrations were analyzed in this study. Based on substrate characteristics and use pattern relevant single source polluters were identified and emission concentrations as well as loads discharged into the sewerage were determined. Effluents from hospitals and laundries but also from wellness resorts showed high effluent concentrations compared to municipal waste water. To describe the fate of QACs during waste water treatment, adsorption and degradation behavior were determined. Additionally the influence of QACs on biological processes, especially nitrification was assessed. Partition coefficient values (log kOC) for QACs were determined between 4.35 for DDAC-C10 and 5.69 for DDAC-C18 (data not shown) indicating the high adsorption potential of those substances to the activated sludge in the waste water treatment plants. Results for BAC-C12–18 were found to be in the same range. Concentrations for nitrification inhibition in waste water treatment plants lay above concentrations found in municipal waste water but in the range of concentrations discharged by single source polluters.
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determination of selected Quaternary Ammonium Compounds by liquid chromatography with mass spectrometry part ii application to sediment and sludge samples in austria
Environmental Pollution, 2007Co-Authors: Elena Martinezcarballo, C Gonzalezbarreiro, Andrea Sitka, Norbe Kreuzinge, Sigrid Scharf, Olive GansAbstract:Abstract Soxhlet extraction and high-performance liquid chromatography (HPLC) coupled to tandem mass spectrometry detection (MS/MS) was used for the determination of selected Quaternary Ammonium Compounds (QACs) in solid samples. The method was applied for the determination of alkyl benzyl, dialkyl and trialkyl Quaternary Ammonium Compounds in sediment and sludge samples in Austria. The overall method quantification limits range from 0.6 to 3 μg/kg for sediments and from 2 to 5 μg/kg for sewage sludges. Mean recoveries between 67% and 95% are achieved. In general sediments were especially contaminated by C12 chain benzalkonium chloride (BAC-C12) as well as by the long C-chain dialkyldimethylAmmonium chloride (DDAC-C18) with a maximum concentration of 3.6 mg/kg and 2.1 mg/kg, respectively. Maxima of 27 mg/kg for DDAC-C10, 25 mg/kg for BAC-C12 and 23 mg/kg for BAC-C14 were determined for sludge samples. The sums of the 12 selected target Compounds range from 22 mg/kg to 103 mg/kg in the sludge samples.
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determination of selected Quaternary Ammonium Compounds by liquid chromatography with mass spectrometry part i application to surface waste and indirect discharge water samples in austria
Environmental Pollution, 2007Co-Authors: Elena Martinezcarballo, C Gonzalezbarreiro, Andrea Sitka, Norbe Kreuzinge, Sigrid Scharf, Maria Furhacke, Olive GansAbstract:Abstract A method for simultaneous quantitative determination of alkyl benzyl, dialkyl and trialkyl Quaternary Ammonium Compounds (QACs) has been developed, validated and subsequently applied to real water samples in Austria. The method employs liquid-liquid extraction (LLE) followed by liquid chromatography/tandem mass spectrometry (LC-MS/MS), using electrospray ionization (ESI) in positive mode. The overall method quantification limits range from 4 to 19 ng/L for the enrichment of 500 mL water samples and analyte recoveries are between 80 and 99%. The method was applied to 62 of the respective water samples without filtration to avoid the loss of the analytes due to the high adsorption capacity of these Compounds. Maxima in the mg/L range, especially in the wastewater of hospitals and laundries, could be detected for the selected target Compounds.
Janusz Pawliszy - One of the best experts on this subject based on the ideXlab platform.
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micelle assisted thin film solid phase microextraction a new approach for determination of Quaternary Ammonium Compounds in environmental samples
Analytical Chemistry, 2014Co-Authors: Ezel Oyaci, Janusz PawliszyAbstract:Determination of Quaternary Ammonium Compounds (QACs) often is considered to be a challenging undertaking owing to secondary interactions of the analytes’ permanently charged Quaternary Ammonium head or hydrophobic tail with the utilized labware. Here, for the first time, a micelle assisted thin-film solid phase microextraction (TF-SPME) using a zwitterionic detergent 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS) as a matrix modifier is introduced as a novel approach for in-laboratory sample preparation of the challenging Compounds. The proposed micelle assisted TF-SPME method offers suppression/enhancement free electrospray ionization of analytes in mass spectrometric detection, minimal interaction of the micelles with the TF-SPME coating, and chromatographic stationary phase and analysis free of secondary interactions. Moreover, it was found that the matrix modifier has multiple functions; when its concentration is found below the critical micelle concentration (CMC), the matrix modi...
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thin film microextraction coupled to lc esi ms ms for determination of Quaternary Ammonium Compounds in water samples
Analytical and Bioanalytical Chemistry, 2014Co-Authors: Ezel Oyaci, Chris Sparham, Janusz PawliszyAbstract:The dual nature of the Quaternary Ammonium Compounds, having permanently charged hydrophilic Quaternary Ammonium heads and long-chain hydrophobic tails, makes the sample preparation step and analysis of these Compounds challenging. A high-throughput method based on thin-film solid-phase microextraction (SPME) and liquid chromatography mass spectrometry was developed for simultaneous quantitative analysis of nine benzylic and aliphatic Quaternary Ammonium Compounds. Chromatographic separation and detection of analytes were obtained in reverse-phase mode in 8 min using a triple quadrupole mass spectrometer. Hydrophilic lipophilic balance particle-coated blades were found to be the most suitable among the different coatings tested in terms of recoveries and carryover on the blades. For desorption solvents, 70/30, v/v (A/B) with 0.1 % formic acid (where A is 10 mM Ammonium acetate in acetonitrile/water (95/5 , v/v) and B is 0.1 % (v/v) formic acid in isopropyl alcohol) was shown to be the most efficient solvent for the desorption of the analytes from the SPME sorbent. The SPME method was optimised in terms of extraction, pH, and preconditioning, as well as extraction and desorption times. Optimum conditions were 45 min of extraction time and 15 min of desorption time, all with agitation. The extraction was found to be optimum in a range of pH 6.0 to 8.0, which is consistent with the natural pH of water samples. Wide linear dynamic ranges with the developed method were obtained for each compound, enabling the application of the method for a wide range of concentrations. The developed method was validated according to the Food and Drug Administration criteria. The proposed method is the first SPME-based approach describing the applicability of the high-throughput thin-film SPME in a 96-well system for analysis of such challenging Compounds.
Elena Martinezcarballo - One of the best experts on this subject based on the ideXlab platform.
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determination of selected Quaternary Ammonium Compounds by liquid chromatography with mass spectrometry part ii application to sediment and sludge samples in austria
Environmental Pollution, 2007Co-Authors: Elena Martinezcarballo, C Gonzalezbarreiro, Andrea Sitka, Norbe Kreuzinge, Sigrid Scharf, Olive GansAbstract:Abstract Soxhlet extraction and high-performance liquid chromatography (HPLC) coupled to tandem mass spectrometry detection (MS/MS) was used for the determination of selected Quaternary Ammonium Compounds (QACs) in solid samples. The method was applied for the determination of alkyl benzyl, dialkyl and trialkyl Quaternary Ammonium Compounds in sediment and sludge samples in Austria. The overall method quantification limits range from 0.6 to 3 μg/kg for sediments and from 2 to 5 μg/kg for sewage sludges. Mean recoveries between 67% and 95% are achieved. In general sediments were especially contaminated by C12 chain benzalkonium chloride (BAC-C12) as well as by the long C-chain dialkyldimethylAmmonium chloride (DDAC-C18) with a maximum concentration of 3.6 mg/kg and 2.1 mg/kg, respectively. Maxima of 27 mg/kg for DDAC-C10, 25 mg/kg for BAC-C12 and 23 mg/kg for BAC-C14 were determined for sludge samples. The sums of the 12 selected target Compounds range from 22 mg/kg to 103 mg/kg in the sludge samples.
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determination of selected Quaternary Ammonium Compounds by liquid chromatography with mass spectrometry part i application to surface waste and indirect discharge water samples in austria
Environmental Pollution, 2007Co-Authors: Elena Martinezcarballo, C Gonzalezbarreiro, Andrea Sitka, Norbe Kreuzinge, Sigrid Scharf, Maria Furhacke, Olive GansAbstract:Abstract A method for simultaneous quantitative determination of alkyl benzyl, dialkyl and trialkyl Quaternary Ammonium Compounds (QACs) has been developed, validated and subsequently applied to real water samples in Austria. The method employs liquid-liquid extraction (LLE) followed by liquid chromatography/tandem mass spectrometry (LC-MS/MS), using electrospray ionization (ESI) in positive mode. The overall method quantification limits range from 4 to 19 ng/L for the enrichment of 500 mL water samples and analyte recoveries are between 80 and 99%. The method was applied to 62 of the respective water samples without filtration to avoid the loss of the analytes due to the high adsorption capacity of these Compounds. Maxima in the mg/L range, especially in the wastewater of hospitals and laundries, could be detected for the selected target Compounds.
