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Frank Thomas Lange - One of the best experts on this subject based on the ideXlab platform.
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analysis and occurrence of seven artificial sweeteners in german waste water and surface water and in soil aquifer treatment sat
Analytical and Bioanalytical Chemistry, 2009Co-Authors: Marco Scheurer, Heinzj Brauch, Frank Thomas LangeAbstract:A method for the simultaneous determination of seven commonly used artificial sweeteners in water is presented. The analytes were extracted by solid phase extraction using Bakerbond SDB 1 cartridges at pH 3 and analyzed by liquid chromatography electrospray ionization tandem mass spectrometry in negative ionization mode. Ionization was enhanced by post-column addition of the alkaline modifier Tris(hydroxymethyl)amino methane. Except for aspartame and neohesperidin dihydrochalcone, recoveries were higher than 75% in potable water with comparable results for surface water. Matrix effects due to reduced extraction yields in undiluted waste water were negligible for aspartame and neotame but considerable for the other compounds. The widespread distribution of Acesulfame, saccharin, cyclamate, and sucralose in the aquatic environment could be proven. Concentrations in two influents of German sewage treatment plants (STPs) were up to 190 μg/L for cyclamate, about 40 μg/L for Acesulfame and saccharin, and less than 1 μg/L for sucralose. Removal in the STPs was limited for Acesulfame and sucralose and >94% for saccharin and cyclamate. The persistence of some artificial sweeteners during soil aquifer treatment was demonstrated and confirmed their environmental relevance. The use of sucralose and Acesulfame as tracers for anthropogenic contamination is conceivable. In German surface waters, Acesulfame was the predominant artificial sweetener with concentrations exceeding 2 μg/L. Other sweeteners were detected up to several hundred nanograms per liter in the order saccharin ≈ cyclamate > sucralose.
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Analysis and occurrence of seven artificial sweeteners in German waste water and surface water and in soil aquifer treatment (SAT)
Analytical and Bioanalytical Chemistry, 2009Co-Authors: Marco Scheurer, Heinzj Brauch, Frank Thomas LangeAbstract:A method for the simultaneous determination of seven commonly used artificial sweeteners in water is presented. The analytes were extracted by solid phase extraction using Bakerbond SDB 1 cartridges at pH 3 and analyzed by liquid chromatography electrospray ionization tandem mass spectrometry in negative ionization mode. Ionization was enhanced by post-column addition of the alkaline modifier Tris(hydroxymethyl)amino methane. Except for aspartame and neohesperidin dihydrochalcone, recoveries were higher than 75% in potable water with comparable results for surface water. Matrix effects due to reduced extraction yields in undiluted waste water were negligible for aspartame and neotame but considerable for the other compounds. The widespread distribution of Acesulfame, saccharin, cyclamate, and sucralose in the aquatic environment could be proven. Concentrations in two influents of German sewage treatment plants (STPs) were up to 190 μg/L for cyclamate, about 40 μg/L for Acesulfame and saccharin, and less than 1 μg/L for sucralose. Removal in the STPs was limited for Acesulfame and sucralose and >94% for saccharin and cyclamate. The persistence of some artificial sweeteners during soil aquifer treatment was demonstrated and confirmed their environmental relevance. The use of sucralose and Acesulfame as tracers for anthropogenic contamination is conceivable. In German surface waters, Acesulfame was the predominant artificial sweetener with concentrations exceeding 2 μg/L. Other sweeteners were detected up to several hundred nanograms per liter in the order saccharin ≈ cyclamate > sucralose. Figure Some artificial sweeteners are excreted unchanged and in particular Acesulfame is a perfect tracer for municipal waste water
Marco Scheurer - One of the best experts on this subject based on the ideXlab platform.
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Transformation of the artificial sweetener Acesulfame by UV light
Science of The Total Environment, 2014Co-Authors: Marco Scheurer, Heinz-jürgen Brauch, Beat Schmutz, Oliver Happel, Richard Wülser, Florian R. StorckAbstract:Abstract The transformation of the artificial sweetener Acesulfame by direct photolysis was investigated at various pH values, in different water types and at various concentration levels. Main photodegradation products of Acesulfame were elucidated and analyzed both in laboratory experiments and in a full-scale waterworks using UV treatment for disinfection purposes. The degradation of Acesulfame was found to be independent of the pH (range 5–11) and followed pseudo first order kinetics in a concentration range between 1 μg∙L − 1 and 10 mg∙L − 1 . Calculated rate constants were in the range between 5.4 · 10 − 3 s − 1 and 7.4 · 10 − 3 s − 1 . The main photodegradation products of Acesulfame were separated by ion exchange chromatography and high performance liquid chromatography and were identified as hydroxylated Acesulfame and iso-Acesulfame by high resolution mass spectrometry and fragmentation experiments. In the case of iso-Acesulfame an intramolecular rearrangement is assumed as the transformation product has a higher polarity and different product ions after MS fragmentation compared to Acesulfame. Minor transformation products were identified as amidosulfonic acid and sulfate by comparison with analytical standards. The transformation pathway was found to be transferable to drinking water production as the identified transformation products were also detected to a similar extent in fortified tap water. In a Swiss full-scale waterworks Acesulfame concentrations were reduced by approximately 30% and one of the main UV transformation products could be qualitatively detected.
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analysis and occurrence of seven artificial sweeteners in german waste water and surface water and in soil aquifer treatment sat
Analytical and Bioanalytical Chemistry, 2009Co-Authors: Marco Scheurer, Heinzj Brauch, Frank Thomas LangeAbstract:A method for the simultaneous determination of seven commonly used artificial sweeteners in water is presented. The analytes were extracted by solid phase extraction using Bakerbond SDB 1 cartridges at pH 3 and analyzed by liquid chromatography electrospray ionization tandem mass spectrometry in negative ionization mode. Ionization was enhanced by post-column addition of the alkaline modifier Tris(hydroxymethyl)amino methane. Except for aspartame and neohesperidin dihydrochalcone, recoveries were higher than 75% in potable water with comparable results for surface water. Matrix effects due to reduced extraction yields in undiluted waste water were negligible for aspartame and neotame but considerable for the other compounds. The widespread distribution of Acesulfame, saccharin, cyclamate, and sucralose in the aquatic environment could be proven. Concentrations in two influents of German sewage treatment plants (STPs) were up to 190 μg/L for cyclamate, about 40 μg/L for Acesulfame and saccharin, and less than 1 μg/L for sucralose. Removal in the STPs was limited for Acesulfame and sucralose and >94% for saccharin and cyclamate. The persistence of some artificial sweeteners during soil aquifer treatment was demonstrated and confirmed their environmental relevance. The use of sucralose and Acesulfame as tracers for anthropogenic contamination is conceivable. In German surface waters, Acesulfame was the predominant artificial sweetener with concentrations exceeding 2 μg/L. Other sweeteners were detected up to several hundred nanograms per liter in the order saccharin ≈ cyclamate > sucralose.
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Analysis and occurrence of seven artificial sweeteners in German waste water and surface water and in soil aquifer treatment (SAT)
Analytical and Bioanalytical Chemistry, 2009Co-Authors: Marco Scheurer, Heinzj Brauch, Frank Thomas LangeAbstract:A method for the simultaneous determination of seven commonly used artificial sweeteners in water is presented. The analytes were extracted by solid phase extraction using Bakerbond SDB 1 cartridges at pH 3 and analyzed by liquid chromatography electrospray ionization tandem mass spectrometry in negative ionization mode. Ionization was enhanced by post-column addition of the alkaline modifier Tris(hydroxymethyl)amino methane. Except for aspartame and neohesperidin dihydrochalcone, recoveries were higher than 75% in potable water with comparable results for surface water. Matrix effects due to reduced extraction yields in undiluted waste water were negligible for aspartame and neotame but considerable for the other compounds. The widespread distribution of Acesulfame, saccharin, cyclamate, and sucralose in the aquatic environment could be proven. Concentrations in two influents of German sewage treatment plants (STPs) were up to 190 μg/L for cyclamate, about 40 μg/L for Acesulfame and saccharin, and less than 1 μg/L for sucralose. Removal in the STPs was limited for Acesulfame and sucralose and >94% for saccharin and cyclamate. The persistence of some artificial sweeteners during soil aquifer treatment was demonstrated and confirmed their environmental relevance. The use of sucralose and Acesulfame as tracers for anthropogenic contamination is conceivable. In German surface waters, Acesulfame was the predominant artificial sweetener with concentrations exceeding 2 μg/L. Other sweeteners were detected up to several hundred nanograms per liter in the order saccharin ≈ cyclamate > sucralose. Figure Some artificial sweeteners are excreted unchanged and in particular Acesulfame is a perfect tracer for municipal waste water
Heinzj Brauch - One of the best experts on this subject based on the ideXlab platform.
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analysis and occurrence of seven artificial sweeteners in german waste water and surface water and in soil aquifer treatment sat
Analytical and Bioanalytical Chemistry, 2009Co-Authors: Marco Scheurer, Heinzj Brauch, Frank Thomas LangeAbstract:A method for the simultaneous determination of seven commonly used artificial sweeteners in water is presented. The analytes were extracted by solid phase extraction using Bakerbond SDB 1 cartridges at pH 3 and analyzed by liquid chromatography electrospray ionization tandem mass spectrometry in negative ionization mode. Ionization was enhanced by post-column addition of the alkaline modifier Tris(hydroxymethyl)amino methane. Except for aspartame and neohesperidin dihydrochalcone, recoveries were higher than 75% in potable water with comparable results for surface water. Matrix effects due to reduced extraction yields in undiluted waste water were negligible for aspartame and neotame but considerable for the other compounds. The widespread distribution of Acesulfame, saccharin, cyclamate, and sucralose in the aquatic environment could be proven. Concentrations in two influents of German sewage treatment plants (STPs) were up to 190 μg/L for cyclamate, about 40 μg/L for Acesulfame and saccharin, and less than 1 μg/L for sucralose. Removal in the STPs was limited for Acesulfame and sucralose and >94% for saccharin and cyclamate. The persistence of some artificial sweeteners during soil aquifer treatment was demonstrated and confirmed their environmental relevance. The use of sucralose and Acesulfame as tracers for anthropogenic contamination is conceivable. In German surface waters, Acesulfame was the predominant artificial sweetener with concentrations exceeding 2 μg/L. Other sweeteners were detected up to several hundred nanograms per liter in the order saccharin ≈ cyclamate > sucralose.
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Analysis and occurrence of seven artificial sweeteners in German waste water and surface water and in soil aquifer treatment (SAT)
Analytical and Bioanalytical Chemistry, 2009Co-Authors: Marco Scheurer, Heinzj Brauch, Frank Thomas LangeAbstract:A method for the simultaneous determination of seven commonly used artificial sweeteners in water is presented. The analytes were extracted by solid phase extraction using Bakerbond SDB 1 cartridges at pH 3 and analyzed by liquid chromatography electrospray ionization tandem mass spectrometry in negative ionization mode. Ionization was enhanced by post-column addition of the alkaline modifier Tris(hydroxymethyl)amino methane. Except for aspartame and neohesperidin dihydrochalcone, recoveries were higher than 75% in potable water with comparable results for surface water. Matrix effects due to reduced extraction yields in undiluted waste water were negligible for aspartame and neotame but considerable for the other compounds. The widespread distribution of Acesulfame, saccharin, cyclamate, and sucralose in the aquatic environment could be proven. Concentrations in two influents of German sewage treatment plants (STPs) were up to 190 μg/L for cyclamate, about 40 μg/L for Acesulfame and saccharin, and less than 1 μg/L for sucralose. Removal in the STPs was limited for Acesulfame and sucralose and >94% for saccharin and cyclamate. The persistence of some artificial sweeteners during soil aquifer treatment was demonstrated and confirmed their environmental relevance. The use of sucralose and Acesulfame as tracers for anthropogenic contamination is conceivable. In German surface waters, Acesulfame was the predominant artificial sweetener with concentrations exceeding 2 μg/L. Other sweeteners were detected up to several hundred nanograms per liter in the order saccharin ≈ cyclamate > sucralose. Figure Some artificial sweeteners are excreted unchanged and in particular Acesulfame is a perfect tracer for municipal waste water
R Van Geldern - One of the best experts on this subject based on the ideXlab platform.
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Quantification of long-term wastewater fluxes at the surface water/groundwater-interface: an integrative model perspective using stable isotopes and Acesulfame.
Science of The Total Environment, 2014Co-Authors: I Engelhardt, J A C Barth, R Bol, M Schulz, T A Ternes, C Schüth, R Van GeldernAbstract:The suitability of Acesulfame to trace wastewater-related surface water fluxes from streams into the hyporheic and riparian zones over long-term periods was investigated. The transport behavior of Acesulfame was compared with the transport of water stable isotopes (δ(18)O or δ(2)H). A calibrated model based on a joint inversion of temperature, Acesulfame, and piezometric pressure heads was employed in a model validation using data sets of Acesulfame and water stable isotopes collected over 5months in a stream and groundwater. The spatial distribution of fresh water within the groundwater resulting from surface water infiltration was estimated by computing groundwater ages and compared with the predicted Acesulfame plume obtained after 153day simulation time. Both, surface water ratios calculated with a mixing equation from water stable isotopes and simulated Acesulfame mass fluxes, were investigated for their ability to estimate the contribution of wastewater-related surface water inflow within groundwater. The results of this study point to limitations for the application of Acesulfame to trace surface water-groundwater interactions properly. Acesulfame completely missed the wastewater-related surface water volumes that still remained in the hyporheic zone under stream-gaining conditions. In contrast, under stream-losing conditions, which developed after periods of stagnating hydraulic exchange, Acesulfame based predictions lead to an overestimation of the surface water volume of up to 25% in the riparian zone. If slow seepage velocities prevail a proportion of Acesulfame might be stored in smaller pores, while when released under fast flowing water conditions it will travel further downstream with the groundwater flow direction. Therefore, under such conditions Acesulfame can be a less-ideal tracer in the hyporheic and riparian zones and additional monitoring with other environmental tracers such as water stable isotopes is highly recommended.
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quantification of long term wastewater fluxes at the surface water groundwater interface an integrative model perspective using stable isotopes and Acesulfame
Science of The Total Environment, 2014Co-Authors: I Engelhardt, J A C Barth, R Bol, M Schulz, T A Ternes, C Schüth, R Van GeldernAbstract:Abstract The suitability of Acesulfame to trace wastewater-related surface water fluxes from streams into the hyporheic and riparian zones over long-term periods was investigated. The transport behavior of Acesulfame was compared with the transport of water stable isotopes (δ 18 O or δ 2 H). A calibrated model based on a joint inversion of temperature, Acesulfame, and piezometric pressure heads was employed in a model validation using data sets of Acesulfame and water stable isotopes collected over 5 months in a stream and groundwater. The spatial distribution of fresh water within the groundwater resulting from surface water infiltration was estimated by computing groundwater ages and compared with the predicted Acesulfame plume obtained after 153 day simulation time. Both, surface water ratios calculated with a mixing equation from water stable isotopes and simulated Acesulfame mass fluxes, were investigated for their ability to estimate the contribution of wastewater-related surface water inflow within groundwater. The results of this study point to limitations for the application of Acesulfame to trace surface water–groundwater interactions properly. Acesulfame completely missed the wastewater-related surface water volumes that still remained in the hyporheic zone under stream-gaining conditions. In contrast, under stream-losing conditions, which developed after periods of stagnating hydraulic exchange, Acesulfame based predictions lead to an overestimation of the surface water volume of up to 25% in the riparian zone. If slow seepage velocities prevail a proportion of Acesulfame might be stored in smaller pores, while when released under fast flowing water conditions it will travel further downstream with the groundwater flow direction. Therefore, under such conditions Acesulfame can be a less-ideal tracer in the hyporheic and riparian zones and additional monitoring with other environmental tracers such as water stable isotopes is highly recommended.
Salvador Massano Cardoso - One of the best experts on this subject based on the ideXlab platform.
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estimated intake of the sweeteners Acesulfame k and aspartame from soft drinks soft drinks based on mineral waters and nectars for a group of portuguese teenage students
Food Additives and Contaminants Part A-chemistry Analysis Control Exposure & Risk Assessment, 2008Co-Authors: Celeste M. Lino, Isabel Costa, Rui Ferreira, A Pena, Salvador Massano CardosoAbstract:In a survey of levels of Acesulfame-K and aspartame in soft drinks and in light nectars, the intake of these intense sweeteners was estimated for a group of teenage students. Acesulfame-K was detected in 72% of the soft drinks, with a mean concentration of 72 mg l−1 and aspartame was found in 92% of the samples with a mean concentration of 89 mg l−1. When data on the content of these sweeteners in soft drinks were analysed according to flavour, cola drinks had the highest mean levels for both sweeteners with 98 and 103 mg l−1 for Acesulfame-K and aspartame, respectively. For soft drinks based on mineral water, aspartame was found in 62% of the samples, with a mean concentration of 82 mg l−1 and Acesulfame-K was found in 77%, with a mean level of 48 mg l−1. All samples of nectars contained Acesulfame-K, with a mean concentration of 128 mg l−1 and aspartame was detected in 80% of the samples with a mean concentration of 73 mg l−1. A frequency questionnaire, designed to identify adolescents having high consu...
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Estimated intake of sweeteners Acesulfame-K and aspartame from soft drinks, soft drinks based on mineral waters and nectars in a scholar group of Portuguese teenagers
Food Additives and Contaminants, 2008Co-Authors: Celeste M. Lino, Rui Ferreira, Isabel M. Costa, Angelina Lopes Simões Pena, Salvador Massano CardosoAbstract:Abstract A surveillance of Acesulfame-K and aspartame levels in soft drinks and in light nectars was undertaken. Furthermore, the estimated intake of these intense sweeteners was also studied in a scholar group of teenagers. Acesulfame-K was detected in 72% of the soft drinks, with a mean concentration of 72 mg/L. Aspartame was found in 92% of the samples. The mean concentration was 89 mg/L. When soft drinks results were analyzed according to the flavour, the cola drinks presented the highest mean levels for both the sweeteners, 98 and 103 mg/L for Acesulfame-K and aspartame, respectively. In respect to soft drinks based on mineral waters, aspartame was found in 62% of the samples. The mean concentration value was 82 mg/L. Acesulfame-K was detected in 77%, with a mean level of 48 mg/L. All samples of nectars showed the presence of Acesulfame-K, being the mean concentration of 128 mg/L. Aspartame was detected in 80% of the samples. The mean concentration was 73 mg/L. A frequency questionnaire, designed to identify adolescents having high consumption of these drinks, was filled in by a randomly extracted sample of teenagers (n=65) living in the city of Coimbra, in the year 2007. The estimated intakes of Acesulfame-K and aspartame for the average consumer were below the acceptable daily intakes (ADIs). For Acesulfame-K the EDI was 0.7 mg/kg b.w./day for soft drinks, 0.2 mg/kg b.w./day for soft drinks based on mineral waters, and 0.5 mg/kg b.w./day for nectars, representing 8.0%, 2.2%, and 5.8% of the ADI, respectively. Similar situation was observed for aspartame. In this way, the EDI for soft drinks was 1.1 mg/kg b.w./day, representing only 2.9% of the ADI. In respect to nectars, the EDI was 0.2 mg/kg b.w./day, what represents 0.5% of the ADI. Soft drinks based on mineral waters showed the lowest EDI values, 0.3 mg/kg b.w./day, accounting with 0.7 % ADI.
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Estimated intake of the sweeteners, Acesulfame-K and aspartame, from soft drinks, soft drinks based on mineral waters and nectars for a group of Portuguese teenage students
Food Additives & Contaminants: Part A, 2008Co-Authors: Celeste M. Lino, Isabel Costa, Rui Ferreira, A Pena, Salvador Massano CardosoAbstract:In a survey of levels of Acesulfame-K and aspartame in soft drinks and in light nectars, the intake of these intense sweeteners was estimated for a group of teenage students. Acesulfame-K was detected in 72% of the soft drinks, with a mean concentration of 72 mg l(-1) and aspartame was found in 92% of the samples with a mean concentration of 89 mg l(-1). When data on the content of these sweeteners in soft drinks were analysed according to flavour, cola drinks had the highest mean levels for both sweeteners with 98 and 103 mg l(-1) for Acesulfame-K and aspartame, respectively. For soft drinks based on mineral water, aspartame was found in 62% of the samples, with a mean concentration of 82 mg l(-1) and Acesulfame-K was found in 77%, with a mean level of 48 mg l(-1). All samples of nectars contained Acesulfame-K, with a mean concentration of 128 mg l(-1) and aspartame was detected in 80% of the samples with a mean concentration of 73 mg l(-1). A frequency questionnaire, designed to identify adolescents having high consumption of these drinks, was completed by a randomly selected sample of teenagers (n = 65) living in the city of Coimbra, in 2007. The estimated daily intakes (EDI) of Acesulfame-K and aspartame for the average consumer were below the acceptable daily intakes (ADIs). For Acesulfame-K, the EDI was 0.7 mg kg(-1) bw day(-1) for soft drinks, 0.2 mg kg(-1) bw day(-1) for soft drinks based on mineral waters, and 0.5 mg kg(-1) bw day(-1) for nectars, representing 8.0%, 2.2%, and 5.8% of the ADI, respectively. A similar situation was observed for aspartame. In this way, the EDI for soft drinks was 1.1 mg kg(-1) day(-1), representing only 2.9% of the ADI. In respect of nectars, the EDI was 0.2 mg kg(-1) bw day(-1), representing 0.5% of the ADI. Soft drinks based on mineral waters showed the lowest EDI values of 0.3 mg kg(-1) bw day(-1), accounting for 0.7% of the ADI.