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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.
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.
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.
William M Wues - One of the best experts on this subject based on the ideXlab platform.
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from antimicrobial activity to mechanism of resistance the multifaceted role of simple quaternary Ammonium Compounds in bacterial eradication
Tetrahedron, 2016Co-Authors: Kevin P. C. Minbiole, Mega C Jennings, Laura E Ato, Jacob W Lack, Melissa C Grenie, Jade E Ladow, Kevi L Cara, Kyle Seife, William M WuesAbstract:Abstract Quaternary Ammonium Compounds (QACs) are a prominent class of antibacterial agents. Drawing inspiration from commercial disinfectants and antimicrobial natural products, we have derivatized structurally diverse tertiary amines to generate several different classes of QACs. We have synthesized over 200 QACs, many of which exhibit potent antibacterial and antibiofilm activity. Analysis of the structure–activity relationship of our Compounds have led to the facile production of inexpensive QACs that display ∼1 μM MIC against a suite of bacteria, and furthermore do not appear to trigger bacterial resistance systems in methicillin-resistant Staphylococcus aureus (MRSA).
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quaternary Ammonium Compounds an antimicrobial mainstay and platform for innovation to address bacterial resistance
ACS Infectious Diseases, 2015Co-Authors: Mega C Jennings, Kevin P. C. Minbiole, William M WuesAbstract:Quaternary Ammonium Compounds (QACs) have represented one of the most visible and effective classes of disinfectants for nearly a century. With simple preparation, wide structural variety, and versatile incorporation into consumer products, there have been manifold developments and applications of these structures. Generally operating via disruption of one of the most fundamental structures in bacteria–the cell membrane–leading to cell lysis and bacterial death, the QACs were once thought to be impervious to resistance. Developments over the past decades, however, have shown this to be far from the truth. It is now known that a large family of bacterial genes (generally termed qac genes) encode efflux pumps capable of expelling many QAC structures from bacterial cells, leading to a decrease in susceptibility to QACs; methods of regulation of qac transcription are also understood. Importantly, qac genes can be horizontally transferred via plasmids to other bacteria and are often transmitted alongside other...
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.