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Javier Hernández-borges - One of the best experts on this subject based on the ideXlab platform.
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Dissipation kinetics of organophosphorus pesticides in milled toasted maize and wheat flour (gofio) during storage.
Food chemistry, 2017Co-Authors: Miguel Ángel González-curbelo, Bárbara Socas-rodríguez, Miguel Herrero, Antonio V. Herrera-herrera, Javier Hernández-borgesAbstract:The dissipation/degradation of the pesticides dimethoate, terbufos, Disulfoton, and pirimiphos-methyl were evaluated in milled toasted maize and wheat flour (gofio) during three months of storage. Their dissipation kinetics and residual levels were determined, as well as their possible decomposition into some of their main transformation products (Disulfoton sulfoxide, terbufos sulfone and Disulfoton sulfone). For this purpose, pesticide-free milled toasted maize and wheat samples were spiked with the pesticides, and they were then stored in the darkness at ambient temperature in a closed container to simulate current storage conditions of such packed food. A multiresidue analysis based on the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method was performed for the simultaneous determination of these pesticides and their metabolites. After three months of storage, the dissipation of residues ranged between 34% (pirimiphos-methyl) and 86% (Disulfoton) for maize gofio and between 69% (terbufos) and 92% (Disulfoton and pirimiphos-methyl) for wheat gofio. The results demonstrated that the degradation was slower in gofio than in wheat gofio and that none of the selected metabolites were detected in any of the samples. Dissipation curves of all studied pesticides fitted to a first-order decay curve in both types of cereals.
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Pesticide residue analysis in cereal-based baby foods using multi-walled carbon nanotubes dispersive solid-phase extraction
Analytical and Bioanalytical Chemistry, 2012Co-Authors: Miguel Ángel González-curbelo, Antonio V. Herrera-herrera, María Asensio-ramos, Javier Hernández-borgesAbstract:In the present study, a new analytical method has been developed for the simultaneous quantification of 15 organophosphorus pesticides, including some of their metabolites, (Disulfoton-sulfoxide, ethoprophos, cadusafos, dimethoate, terbufos, Disulfoton, chlorpyrifos-methyl, malaoxon, fenitrothion, pirimiphos-methyl, malathion, chlorpyrifos, terbufos-sulfone, Disulfoton-sulfone and fensulfothion) in three different types of commercial cereal-based baby foods. Dispersive solid-phase extraction (dSPE) with multi-walled carbon nanotubes (MWCNTs) was used together with gas chromatography with nitrogen phosphorus detection. Most favorable conditions involved a previous ultrasound-assisted extraction of the sample with acetonitrile containing formic acid. After evaporation of the extract and redissolution in water, a dSPE procedure was carried out with MWCNTs. The whole method was validated in terms of repeatability, linearity, precision and accuracy and matrix effect was also evaluated. Absolute recoveries were in the range 64–105 % with relative standard deviation values below 7.6 %. Limits of quantification achieved ranged from 0.31 to 5.50 μg/kg, which were lower than the European Union maximum residue limits for pesticide residues in cereal-based baby foods.
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Determination of pesticides and their metabolites in processed cereal samples
2012Co-Authors: Miguel Ángel González-curbelo, Javier Hernández-borges, Teresa M. Borges-miquel, Miguel Ángel Rodríguez-delgadoAbstract:Fifteen pesticides including some of their metabolites (Disulfoton sulfoxide, ethoprophos, cadusafos, dimethoate, terbufos, Disulfoton, chlorpyrifos-methyl, malaoxon, fenitrothion, pirimiphos-methyl, malathion, chlorpyrifos, terbufos sulfone, Disulfoton sulfone and fensulfothion) were analysed in milled toasted wheat and maize as well as in wheat flour and baby cereals. The QuEChERS (quick, easy, cheap, effective, rugged and safe) methodology was used and its dispersive solid-phase extraction procedure was optimised by means of an experimental design with the aim of reducing the amount of co-extracted lipids and obtaining a clean extract. Gas chromatography with nitrogen phosphorus detection were used as the separation and detection techniques, respectively. The method was validated in terms of selectivity, recoveries, calibration, precision and accuracy as well as matrix effects. Limits of detection were between 0.07 and 34.8 µg kg−1 with recoveries in the range of 71–110% (relative standard deviations were below 9%). A total of 40 samples of different origin were analysed. Residues of pirimiphos-methyl were found in six of the samples at concentrations in the range 0.08–0.47 mg kg−1, which were below the MRLs established for this pesticide in cereal grains. Tandem mass spectrometry confirmation was also carried out in order to identify unequivocally the presence of this pesticide.
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Determination of pesticides and their metabolites in processed cereal samples
Food Additives and Contaminants Part A-chemistry Analysis Control Exposure & Risk Assessment, 2011Co-Authors: Miguel Ángel González-curbelo, Javier Hernández-borges, Teresa M. Borges-miquel, Miguel Ángel Rodríguez-delgadoAbstract:Fifteen pesticides including some of their metabolites (Disulfoton sulfoxide, ethoprophos, cadusafos, dimethoate, terbufos, Disulfoton, chlorpyrifos-methyl, malaoxon, fenitrothion, pirimiphos-methyl, malathion, chlorpyrifos, terbufos sulfone, Disulfoton sulfone and fensulfothion) were analysed in milled toasted wheat and maize as well as in wheat flour and baby cereals. The QuEChERS (quick, easy, cheap, effective, rugged and safe) methodology was used and its dispersive solid-phase extraction procedure was optimised by means of an experimental design with the aim of reducing the amount of co-extracted lipids and obtaining a clean extract. Gas chromatography with nitrogen phosphorus detection were used as the separation and detection techniques, respectively. The method was validated in terms of selectivity, recoveries, calibration, precision and accuracy as well as matrix effects. Limits of detection were between 0.07 and 34.8 µg kg−1 with recoveries in the range of 71–110% (relative standard deviations w...
Miguel Ángel González-curbelo - One of the best experts on this subject based on the ideXlab platform.
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Dissipation kinetics of organophosphorus pesticides in milled toasted maize and wheat flour (gofio) during storage.
Food chemistry, 2017Co-Authors: Miguel Ángel González-curbelo, Bárbara Socas-rodríguez, Miguel Herrero, Antonio V. Herrera-herrera, Javier Hernández-borgesAbstract:The dissipation/degradation of the pesticides dimethoate, terbufos, Disulfoton, and pirimiphos-methyl were evaluated in milled toasted maize and wheat flour (gofio) during three months of storage. Their dissipation kinetics and residual levels were determined, as well as their possible decomposition into some of their main transformation products (Disulfoton sulfoxide, terbufos sulfone and Disulfoton sulfone). For this purpose, pesticide-free milled toasted maize and wheat samples were spiked with the pesticides, and they were then stored in the darkness at ambient temperature in a closed container to simulate current storage conditions of such packed food. A multiresidue analysis based on the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method was performed for the simultaneous determination of these pesticides and their metabolites. After three months of storage, the dissipation of residues ranged between 34% (pirimiphos-methyl) and 86% (Disulfoton) for maize gofio and between 69% (terbufos) and 92% (Disulfoton and pirimiphos-methyl) for wheat gofio. The results demonstrated that the degradation was slower in gofio than in wheat gofio and that none of the selected metabolites were detected in any of the samples. Dissipation curves of all studied pesticides fitted to a first-order decay curve in both types of cereals.
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Pesticide residue analysis in cereal-based baby foods using multi-walled carbon nanotubes dispersive solid-phase extraction
Analytical and Bioanalytical Chemistry, 2012Co-Authors: Miguel Ángel González-curbelo, Antonio V. Herrera-herrera, María Asensio-ramos, Javier Hernández-borgesAbstract:In the present study, a new analytical method has been developed for the simultaneous quantification of 15 organophosphorus pesticides, including some of their metabolites, (Disulfoton-sulfoxide, ethoprophos, cadusafos, dimethoate, terbufos, Disulfoton, chlorpyrifos-methyl, malaoxon, fenitrothion, pirimiphos-methyl, malathion, chlorpyrifos, terbufos-sulfone, Disulfoton-sulfone and fensulfothion) in three different types of commercial cereal-based baby foods. Dispersive solid-phase extraction (dSPE) with multi-walled carbon nanotubes (MWCNTs) was used together with gas chromatography with nitrogen phosphorus detection. Most favorable conditions involved a previous ultrasound-assisted extraction of the sample with acetonitrile containing formic acid. After evaporation of the extract and redissolution in water, a dSPE procedure was carried out with MWCNTs. The whole method was validated in terms of repeatability, linearity, precision and accuracy and matrix effect was also evaluated. Absolute recoveries were in the range 64–105 % with relative standard deviation values below 7.6 %. Limits of quantification achieved ranged from 0.31 to 5.50 μg/kg, which were lower than the European Union maximum residue limits for pesticide residues in cereal-based baby foods.
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Determination of pesticides and their metabolites in processed cereal samples
2012Co-Authors: Miguel Ángel González-curbelo, Javier Hernández-borges, Teresa M. Borges-miquel, Miguel Ángel Rodríguez-delgadoAbstract:Fifteen pesticides including some of their metabolites (Disulfoton sulfoxide, ethoprophos, cadusafos, dimethoate, terbufos, Disulfoton, chlorpyrifos-methyl, malaoxon, fenitrothion, pirimiphos-methyl, malathion, chlorpyrifos, terbufos sulfone, Disulfoton sulfone and fensulfothion) were analysed in milled toasted wheat and maize as well as in wheat flour and baby cereals. The QuEChERS (quick, easy, cheap, effective, rugged and safe) methodology was used and its dispersive solid-phase extraction procedure was optimised by means of an experimental design with the aim of reducing the amount of co-extracted lipids and obtaining a clean extract. Gas chromatography with nitrogen phosphorus detection were used as the separation and detection techniques, respectively. The method was validated in terms of selectivity, recoveries, calibration, precision and accuracy as well as matrix effects. Limits of detection were between 0.07 and 34.8 µg kg−1 with recoveries in the range of 71–110% (relative standard deviations were below 9%). A total of 40 samples of different origin were analysed. Residues of pirimiphos-methyl were found in six of the samples at concentrations in the range 0.08–0.47 mg kg−1, which were below the MRLs established for this pesticide in cereal grains. Tandem mass spectrometry confirmation was also carried out in order to identify unequivocally the presence of this pesticide.
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Determination of pesticides and their metabolites in processed cereal samples
Food Additives and Contaminants Part A-chemistry Analysis Control Exposure & Risk Assessment, 2011Co-Authors: Miguel Ángel González-curbelo, Javier Hernández-borges, Teresa M. Borges-miquel, Miguel Ángel Rodríguez-delgadoAbstract:Fifteen pesticides including some of their metabolites (Disulfoton sulfoxide, ethoprophos, cadusafos, dimethoate, terbufos, Disulfoton, chlorpyrifos-methyl, malaoxon, fenitrothion, pirimiphos-methyl, malathion, chlorpyrifos, terbufos sulfone, Disulfoton sulfone and fensulfothion) were analysed in milled toasted wheat and maize as well as in wheat flour and baby cereals. The QuEChERS (quick, easy, cheap, effective, rugged and safe) methodology was used and its dispersive solid-phase extraction procedure was optimised by means of an experimental design with the aim of reducing the amount of co-extracted lipids and obtaining a clean extract. Gas chromatography with nitrogen phosphorus detection were used as the separation and detection techniques, respectively. The method was validated in terms of selectivity, recoveries, calibration, precision and accuracy as well as matrix effects. Limits of detection were between 0.07 and 34.8 µg kg−1 with recoveries in the range of 71–110% (relative standard deviations w...
Antonio V. Herrera-herrera - One of the best experts on this subject based on the ideXlab platform.
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Dissipation kinetics of organophosphorus pesticides in milled toasted maize and wheat flour (gofio) during storage.
Food chemistry, 2017Co-Authors: Miguel Ángel González-curbelo, Bárbara Socas-rodríguez, Miguel Herrero, Antonio V. Herrera-herrera, Javier Hernández-borgesAbstract:The dissipation/degradation of the pesticides dimethoate, terbufos, Disulfoton, and pirimiphos-methyl were evaluated in milled toasted maize and wheat flour (gofio) during three months of storage. Their dissipation kinetics and residual levels were determined, as well as their possible decomposition into some of their main transformation products (Disulfoton sulfoxide, terbufos sulfone and Disulfoton sulfone). For this purpose, pesticide-free milled toasted maize and wheat samples were spiked with the pesticides, and they were then stored in the darkness at ambient temperature in a closed container to simulate current storage conditions of such packed food. A multiresidue analysis based on the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method was performed for the simultaneous determination of these pesticides and their metabolites. After three months of storage, the dissipation of residues ranged between 34% (pirimiphos-methyl) and 86% (Disulfoton) for maize gofio and between 69% (terbufos) and 92% (Disulfoton and pirimiphos-methyl) for wheat gofio. The results demonstrated that the degradation was slower in gofio than in wheat gofio and that none of the selected metabolites were detected in any of the samples. Dissipation curves of all studied pesticides fitted to a first-order decay curve in both types of cereals.
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Pesticide residue analysis in cereal-based baby foods using multi-walled carbon nanotubes dispersive solid-phase extraction
Analytical and Bioanalytical Chemistry, 2012Co-Authors: Miguel Ángel González-curbelo, Antonio V. Herrera-herrera, María Asensio-ramos, Javier Hernández-borgesAbstract:In the present study, a new analytical method has been developed for the simultaneous quantification of 15 organophosphorus pesticides, including some of their metabolites, (Disulfoton-sulfoxide, ethoprophos, cadusafos, dimethoate, terbufos, Disulfoton, chlorpyrifos-methyl, malaoxon, fenitrothion, pirimiphos-methyl, malathion, chlorpyrifos, terbufos-sulfone, Disulfoton-sulfone and fensulfothion) in three different types of commercial cereal-based baby foods. Dispersive solid-phase extraction (dSPE) with multi-walled carbon nanotubes (MWCNTs) was used together with gas chromatography with nitrogen phosphorus detection. Most favorable conditions involved a previous ultrasound-assisted extraction of the sample with acetonitrile containing formic acid. After evaporation of the extract and redissolution in water, a dSPE procedure was carried out with MWCNTs. The whole method was validated in terms of repeatability, linearity, precision and accuracy and matrix effect was also evaluated. Absolute recoveries were in the range 64–105 % with relative standard deviation values below 7.6 %. Limits of quantification achieved ranged from 0.31 to 5.50 μg/kg, which were lower than the European Union maximum residue limits for pesticide residues in cereal-based baby foods.
Christian Schlatter - One of the best experts on this subject based on the ideXlab platform.
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Toxicity of Organophosphorus Insecticides in the Zebra Mussel, Dreissena polymorpha P.
Archives of Environmental Contamination and Toxicology, 1996Co-Authors: Carole Dauberschmidt, Daniel R. Dietrich, Christian SchlatterAbstract:The 96-h toxicity of four organophosphates (thiometon, Disulfoton, malathion, and demeton-S-methyl, the oxygen analogue of thiometon) in the freshwater bivalve mollusc Dreissena polymorpha was tested using different nominal concentrations ranging between 6 and 50 mg/L. No mortalities were observed in mussels exposed to malathion and demeton-S-methyl (26 mg/L and 6 mg/L, respectively), and at the lowest concentrations of thiometon and Disulfoton (6 and 10 mg/L, respectively). At higher thiometon and Disulfoton concentrations, mortalities occurred. At the highest concentrations of 50 mg thiometon/L and 30 mg Disulfoton/L, mussel mortalities of 88 and 93%, respectively, were determined. Organophosphate concentrations of up to a factor 10 times higher than in the ambient water were found in exposed mussels, irrespective of whether they were alive or dead. The search for organophosphate metabolites via GC/MS analysis of mussel tissue extracts was negative, suggesting lacking or low oxidative activation of the insecticides used. The mollusc is highly resistant to toxic effects of organophosphate insecticides and their biological active oxygen analogues.
Carole Dauberschmidt - One of the best experts on this subject based on the ideXlab platform.
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Toxicity of Organophosphorus Insecticides in the Zebra Mussel, Dreissena polymorpha P.
Archives of Environmental Contamination and Toxicology, 1996Co-Authors: Carole Dauberschmidt, Daniel R. Dietrich, Christian SchlatterAbstract:The 96-h toxicity of four organophosphates (thiometon, Disulfoton, malathion, and demeton-S-methyl, the oxygen analogue of thiometon) in the freshwater bivalve mollusc Dreissena polymorpha was tested using different nominal concentrations ranging between 6 and 50 mg/L. No mortalities were observed in mussels exposed to malathion and demeton-S-methyl (26 mg/L and 6 mg/L, respectively), and at the lowest concentrations of thiometon and Disulfoton (6 and 10 mg/L, respectively). At higher thiometon and Disulfoton concentrations, mortalities occurred. At the highest concentrations of 50 mg thiometon/L and 30 mg Disulfoton/L, mussel mortalities of 88 and 93%, respectively, were determined. Organophosphate concentrations of up to a factor 10 times higher than in the ambient water were found in exposed mussels, irrespective of whether they were alive or dead. The search for organophosphate metabolites via GC/MS analysis of mussel tissue extracts was negative, suggesting lacking or low oxidative activation of the insecticides used. The mollusc is highly resistant to toxic effects of organophosphate insecticides and their biological active oxygen analogues.
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a n d Toxicalogy © 1996 Springer-Verlag New York Inc. To:xicity of Organophosphorus Insecticides in the Zebra Mussel, Dreissena
1995Co-Authors: Polymorpha P, Carole Dauberschmidt, Daniel R. Dietrich, C. SchlauerAbstract:Abstract. The 96-h toxieity of four organophosphates (thio-meton, Disulfoton, malathion, and demeton-S-methyl, the oxy-gen analogue of thiometon) in the freshwater bivalve molluse Dreissena polymorpha was tested using different nominal con-centrations ranging between 6 and 50 mglL. No mortalities were observed in musseis exposed to malathion and demeton-S-methyl (26 mglL and 6 mglL, respectively), and at the lowest eoncentrations of thiometon and Disulfoton (6 and 10 mglL, respectively). At higher thiometon and Disulfoton concentra-tions, mortalities occurred. At the highest concentrations of 50 mg thiometonIL and 30 mg DisulfotonIL, mussei mortalities of 88 and 93%, respectively, were determined. Organophosphate concentrations of up to a factor 10 times higher than in the ambient water were found in exposed musseis, irrespective of whether they were alive or dead. The search for organophos-phate metabolites via GCIMS analysis of mussei tissue extraets was negative, suggesting lacking or low oxidative activation of the insecticides used. The mollusc is highly resistant to toxie effects of organophosphate insectieides and their biologieal aetive oxygen analogues. On November 1, 1986, a pestieide storing facility at Sandoz in Basel (Switzerland) caught fire. In order to extinguish the fire, water was pumped at high volurnes from the nearby river Rhine. This water found its way back into the river Rhine due to overflowing sewage canals (Capel et al. 1988; Güttinger and Stumm 1992). Along with the fire-extinguishing water, pesticides stored in the affeeted facility were swept into the river. Among these pesticides were organophosphate insecti-eides, mainly thiometon and Disulfoton, mereurial-based fungi-eides, and herbicides. Consequently, the river Rhine ecosyste