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Wilhelm Puttmann - One of the best experts on this subject based on the ideXlab platform.
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Temporal concentration changes of DEET, TCEP, Terbutryn, and nonylphenols in freshwater streams of Hesse, Germany: possible influence of mandatory regulations and voluntary environmental agreements
Environmental Science and Pollution Research, 2009Co-Authors: Kristin Quednow, Wilhelm PuttmannAbstract:Background, aim, and scope The present study focuses on the temporal concentration changes of four common organic pollutants in small freshwater streams of Hesse, Germany. The substances (tris(2-chloroethyl)phosphate (TCEP), the technical isomer mixture of 4-nonylphenol (NP), 2-( t -butylamino)-4-(ethylamino)-6-(methylthio)- s -triazine (Terbutryn), and N , N -diethyl- m -toluamide (DEET)) are subject to differing regulations. Whereas the use of NP and the related nonylphenolethoxylates (NPEOs) are almost completely banned under EU directive 2003/53/EC, the herbicide Terbutryn is only restricted for use as a herbicide in the majority of member states of the European Union (EU). In contrast, TCEP and DEET are not regulated by legislation, but have been replaced in some products through consumer pressure. The impact of regulation on the environmental concentrations of these pollutants is discussed. Materials and methods The substances were monitored in small freshwater streams in the Hessisches Ried region, Germany, during the period September 2003 to September 2006. The samples were extracted with solid phase extraction (SPE) and analyzed by coupled gas chromatography–mass spectrometry (GC–MS). Results All target compounds were detected frequently within the fresh water streams of the study area. Monitoring in the study area revealed a significant concentration decrease only for NP. For the other three compounds, no significant concentration decrease was observed. Terbutryn concentrations and loads showed a seasonal trend with higher levels in summer and autumn, but were also present in winter and spring. Concentrations of TCEP and DEET were in the range of prior investigations. Discussion The decrease of NP concentrations and loads during the sampling period indicates that the regulation of NP and NP ethoxylates has led to a significant improvement in reducing the occurrence of this compound in the aquatic environment. Furthermore, the ban on agricultural use of Terbutryn at the end of 2003 had no discernable influence on Terbutryn concentrations in the following years. Conclusions The benefits of national bans or self-regulations by manufacturers on several chemicals appear to be limited. In contrast, the European-wide ban (of NP) revealed to be effective in preventing the substance from entering the aquatic environment on a large scale and reduced the NP concentration to an acceptable level (i.e., below the PNEC). Recommendations and perspectives Further research is needed to investigate diffuse sources and point sources of Terbutryn not related to agriculture. Further research is required to find an explanation for the ongoing high concentration of TCEP in river water despite of the supposed replacement of TCEP by TCPP already in the 1990s.
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temporal concentration changes of deet tcep Terbutryn and nonylphenols in freshwater streams of hesse germany possible influence of mandatory regulations and voluntary environmental agreements
Environmental Science and Pollution Research, 2009Co-Authors: Kristin Quednow, Wilhelm PuttmannAbstract:Background, aim, and scope The present study focuses on the temporal concentration changes of four common organic pollutants in small freshwater streams of Hesse, Germany. The substances (tris(2-chloroethyl)phosphate (TCEP), the technical isomer mixture of 4-nonylphenol (NP), 2-(t-butylamino)-4-(ethylamino)-6-(methylthio)-s-triazine (Terbutryn), and N,N-diethyl-m-toluamide (DEET)) are subject to differing regulations. Whereas the use of NP and the related nonylphenolethoxylates (NPEOs) are almost completely banned under EU directive 2003/53/EC, the herbicide Terbutryn is only restricted for use as a herbicide in the majority of member states of the European Union (EU). In contrast, TCEP and DEET are not regulated by legislation, but have been replaced in some products through consumer pressure. The impact of regulation on the environmental concentrations of these pollutants is discussed.
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monitoring Terbutryn pollution in small rivers of hesse germany
Journal of Environmental Monitoring, 2007Co-Authors: Kristin Quednow, Wilhelm PuttmannAbstract:Four small river systems in Hesse, Germany, were investigated with respect to seasonal and spatial concentrations of the herbicide Terbutryn [2-(t-butylamino)-4-(ethylamino)-6-(methylthio)-s-triazine]. Despite introduction of a ban on its use as a herbicide in July 2003, Terbutryn was still present in the rivers during the whole sampling period from September 2003 to September 2006, and there was no trend of decreasing concentration during this time. In the Weschnitz and Modau river systems the mean Terbutryn concentration exceeded the German drinking water ordinance threshold value for single biocides. Maximum concentrations of up to 5.6 μg l−1 were determined in the Weschnitz River. Higher Terbutryn concentrations in summer are suggested to originate from agricultural sources, as well as from sediment redissolution. Effluents of two sewage treatment plants had high Terbutryn concentrations, indicating that Terbutryn enters the rivers from this source. Sources other than agriculture must explain Terbutryn occurrence in the rivers during winter, when farm pesticide application typically ceases. The potential for mobilization of Terbutryn from sediments and leaching from soils are discussed.
Kristin Quednow - One of the best experts on this subject based on the ideXlab platform.
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Temporal concentration changes of DEET, TCEP, Terbutryn, and nonylphenols in freshwater streams of Hesse, Germany: possible influence of mandatory regulations and voluntary environmental agreements
Environmental Science and Pollution Research, 2009Co-Authors: Kristin Quednow, Wilhelm PuttmannAbstract:Background, aim, and scope The present study focuses on the temporal concentration changes of four common organic pollutants in small freshwater streams of Hesse, Germany. The substances (tris(2-chloroethyl)phosphate (TCEP), the technical isomer mixture of 4-nonylphenol (NP), 2-( t -butylamino)-4-(ethylamino)-6-(methylthio)- s -triazine (Terbutryn), and N , N -diethyl- m -toluamide (DEET)) are subject to differing regulations. Whereas the use of NP and the related nonylphenolethoxylates (NPEOs) are almost completely banned under EU directive 2003/53/EC, the herbicide Terbutryn is only restricted for use as a herbicide in the majority of member states of the European Union (EU). In contrast, TCEP and DEET are not regulated by legislation, but have been replaced in some products through consumer pressure. The impact of regulation on the environmental concentrations of these pollutants is discussed. Materials and methods The substances were monitored in small freshwater streams in the Hessisches Ried region, Germany, during the period September 2003 to September 2006. The samples were extracted with solid phase extraction (SPE) and analyzed by coupled gas chromatography–mass spectrometry (GC–MS). Results All target compounds were detected frequently within the fresh water streams of the study area. Monitoring in the study area revealed a significant concentration decrease only for NP. For the other three compounds, no significant concentration decrease was observed. Terbutryn concentrations and loads showed a seasonal trend with higher levels in summer and autumn, but were also present in winter and spring. Concentrations of TCEP and DEET were in the range of prior investigations. Discussion The decrease of NP concentrations and loads during the sampling period indicates that the regulation of NP and NP ethoxylates has led to a significant improvement in reducing the occurrence of this compound in the aquatic environment. Furthermore, the ban on agricultural use of Terbutryn at the end of 2003 had no discernable influence on Terbutryn concentrations in the following years. Conclusions The benefits of national bans or self-regulations by manufacturers on several chemicals appear to be limited. In contrast, the European-wide ban (of NP) revealed to be effective in preventing the substance from entering the aquatic environment on a large scale and reduced the NP concentration to an acceptable level (i.e., below the PNEC). Recommendations and perspectives Further research is needed to investigate diffuse sources and point sources of Terbutryn not related to agriculture. Further research is required to find an explanation for the ongoing high concentration of TCEP in river water despite of the supposed replacement of TCEP by TCPP already in the 1990s.
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temporal concentration changes of deet tcep Terbutryn and nonylphenols in freshwater streams of hesse germany possible influence of mandatory regulations and voluntary environmental agreements
Environmental Science and Pollution Research, 2009Co-Authors: Kristin Quednow, Wilhelm PuttmannAbstract:Background, aim, and scope The present study focuses on the temporal concentration changes of four common organic pollutants in small freshwater streams of Hesse, Germany. The substances (tris(2-chloroethyl)phosphate (TCEP), the technical isomer mixture of 4-nonylphenol (NP), 2-(t-butylamino)-4-(ethylamino)-6-(methylthio)-s-triazine (Terbutryn), and N,N-diethyl-m-toluamide (DEET)) are subject to differing regulations. Whereas the use of NP and the related nonylphenolethoxylates (NPEOs) are almost completely banned under EU directive 2003/53/EC, the herbicide Terbutryn is only restricted for use as a herbicide in the majority of member states of the European Union (EU). In contrast, TCEP and DEET are not regulated by legislation, but have been replaced in some products through consumer pressure. The impact of regulation on the environmental concentrations of these pollutants is discussed.
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monitoring Terbutryn pollution in small rivers of hesse germany
Journal of Environmental Monitoring, 2007Co-Authors: Kristin Quednow, Wilhelm PuttmannAbstract:Four small river systems in Hesse, Germany, were investigated with respect to seasonal and spatial concentrations of the herbicide Terbutryn [2-(t-butylamino)-4-(ethylamino)-6-(methylthio)-s-triazine]. Despite introduction of a ban on its use as a herbicide in July 2003, Terbutryn was still present in the rivers during the whole sampling period from September 2003 to September 2006, and there was no trend of decreasing concentration during this time. In the Weschnitz and Modau river systems the mean Terbutryn concentration exceeded the German drinking water ordinance threshold value for single biocides. Maximum concentrations of up to 5.6 μg l−1 were determined in the Weschnitz River. Higher Terbutryn concentrations in summer are suggested to originate from agricultural sources, as well as from sediment redissolution. Effluents of two sewage treatment plants had high Terbutryn concentrations, indicating that Terbutryn enters the rivers from this source. Sources other than agriculture must explain Terbutryn occurrence in the rivers during winter, when farm pesticide application typically ceases. The potential for mobilization of Terbutryn from sediments and leaching from soils are discussed.
Andres Herguedas - One of the best experts on this subject based on the ideXlab platform.
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influence of temperature on the volatilization of triallate and Terbutryn from two soils
Pest Management Science, 2000Co-Authors: Maria T Tabernero, Javier Alvarezbenedi, Julian Atienza, Andres HerguedasAbstract:The rate of volatilization of the formulated herbicides triallate and Terbutryn was studied in a volatilization chamber under controlled laboratory conditions using two soils with sand and loam textures, respectively. The influence of the most relevant experimental variables was investigated by measuring the amount of volatilized herbicides after their incorporation to the soils. The effect of soil temperature was studied in the range from 5 °C to 25 °C. Initial soil water content was fixed at field capacity depending on the physical characteristics of each soil. The volatilized herbicide was trapped in C18 cartridges during different time intervals and analyzed by HPLC. The volatilization losses for triallate ranged from 7 to 58%, whereas the losses for Terbutryn ranged from 1 to 6%. Sorption and volatilization resulted in two coupled effects of major importance in these experiments: the sorption process was favoured as temperature decreased, whereas volatilization increased as temperature increased. © 2000 Society of Chemical Industry
Hyunwook Choi - One of the best experts on this subject based on the ideXlab platform.
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analytical method validation for Terbutryn using gas chromatography ion trap gas chromatography mass selective detector and liquid chromatography triple quadrupole mass spectrometers
Food Science and Biotechnology, 2018Co-Authors: Hae Won Jang, Hyunwook ChoiAbstract:Analytical methods including solvent extraction followed by gas chromatography/ion-trap (GC/IT) with scan and MS/MS mode, a GC/mass selective detector (GC/MSD), and liquid chromatography/triple quadrupole mass spectrometers (LC/MS/MS) were optimized to identify and quantify Terbutryn. The spike recovery was 96.5% using GC/IT with scan mode and 103.5% with MS/MS mode, 90.3% by GC/MSD, and 92.5% by LC/MS/MS. The limit of detection (LOD) was 0.0015 mg/kg by GC/IT with scan, 0.026 mg/kg with MS/MS mode, 0.015 mg/kg with GC/MSD, and 0.026 mg/kg by LC/MS/MS. Of the four methods, GC/IT with scan mode was determined to be the most sensitive (with LOD: 0.0015 mg/kg and limit of quantitation (LOQ): 0.0047 mg/kg), rapid (retention time: 9.6 min) and the most precise method (relative standard deviation: 17%) for the quantification of Terbutryn. GC/IT with scan mode proved to be the more sensitive analytical method for Terbutryn than other methods in this study, showing better accuracy and rapid analysis.
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Analytical method validation for Terbutryn using gas chromatography/ion trap, gas chromatography/mass selective detector, and liquid chromatography/triple quadrupole mass spectrometers.
Food Science and Biotechnology, 2018Co-Authors: Hae Won Jang, Hyunwook ChoiAbstract:Analytical methods including solvent extraction followed by gas chromatography/ion-trap (GC/IT) with scan and MS/MS mode, a GC/mass selective detector (GC/MSD), and liquid chromatography/triple quadrupole mass spectrometers (LC/MS/MS) were optimized to identify and quantify Terbutryn. The spike recovery was 96.5% using GC/IT with scan mode and 103.5% with MS/MS mode, 90.3% by GC/MSD, and 92.5% by LC/MS/MS. The limit of detection (LOD) was 0.0015 mg/kg by GC/IT with scan, 0.026 mg/kg with MS/MS mode, 0.015 mg/kg with GC/MSD, and 0.026 mg/kg by LC/MS/MS. Of the four methods, GC/IT with scan mode was determined to be the most sensitive (with LOD: 0.0015 mg/kg and limit of quantitation (LOQ): 0.0047 mg/kg), rapid (retention time: 9.6 min) and the most precise method (relative standard deviation: 17%) for the quantification of Terbutryn. GC/IT with scan mode proved to be the more sensitive analytical method for Terbutryn than other methods in this study, showing better accuracy and rapid analysis.
Maria T Tabernero - One of the best experts on this subject based on the ideXlab platform.
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influence of temperature on the volatilization of triallate and Terbutryn from two soils
Pest Management Science, 2000Co-Authors: Maria T Tabernero, Javier Alvarezbenedi, Julian Atienza, Andres HerguedasAbstract:The rate of volatilization of the formulated herbicides triallate and Terbutryn was studied in a volatilization chamber under controlled laboratory conditions using two soils with sand and loam textures, respectively. The influence of the most relevant experimental variables was investigated by measuring the amount of volatilized herbicides after their incorporation to the soils. The effect of soil temperature was studied in the range from 5 °C to 25 °C. Initial soil water content was fixed at field capacity depending on the physical characteristics of each soil. The volatilized herbicide was trapped in C18 cartridges during different time intervals and analyzed by HPLC. The volatilization losses for triallate ranged from 7 to 58%, whereas the losses for Terbutryn ranged from 1 to 6%. Sorption and volatilization resulted in two coupled effects of major importance in these experiments: the sorption process was favoured as temperature decreased, whereas volatilization increased as temperature increased. © 2000 Society of Chemical Industry
