The Experts below are selected from a list of 246 Experts worldwide ranked by ideXlab platform
Michael S. Roberts - One of the best experts on this subject based on the ideXlab platform.
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High lethality and minimal variation after acute self-poisoning with Carbamate Insecticides in Sri Lanka - implications for global suicide prevention.
Clinical Toxicology, 2016Co-Authors: Thomas Lamb, Liza R. Selvarajah, Fahim Mohamed, Shaluka Jayamanne, Indika Gawarammana, Ahmed Mostafa, Nicholas A. Buckley, Michael S. Roberts, Michael EddlestonAbstract:AbstractBackground: Highly hazardous organophosphorus (OP) Insecticides are responsible for most pesticide poisoning deaths. As they are removed from agricultural practice, they are often replaced by Carbamate Insecticides of perceived lower toxicity. However, relatively little is known about poisoning with these Insecticides.Methods: We prospectively studied 1288 patients self-poisoned with Carbamate Insecticides admitted to six Sri Lankan hospitals. Clinical outcomes were recorded for each patient and plasma Carbamate concentration measured in a sample to confirm the Carbamate ingested.Findings: Patients had ingested 3% carbofuran powder (719), carbosulfan EC25 liquid (25% w/v, 389), or fenobucarb EC50 liquid (50% w/v, 127) formulations, Carbamate Insecticides of WHO Toxicity Classes Ib, II, and II, respectively. Intubation and ventilation was required for 183 (14.2%) patients while 71 (5.5%) died. Compared with carbofuran, poisoning with carbosulfan or fenobucarb was associated with significantly highe...
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simultaneous quantification of Carbamate Insecticides in human plasma by liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2011Co-Authors: Ahmed Mostafa, Michael S. Roberts, Gregory Medley, Darren M Roberts, Mosaad S Mohamed, Abdalla A Elshanawani, Xin LiuAbstract:Carbofuran (CFN), carbosulfan (CSN) and fenobucarb (FBC) are Carbamate pesticides that are widely used in gardening and agriculture for the control of insects. Human poisoning due to occupational or self-poisoning exposures is also reported, so assays are required to quantify the plasma concentration of these Insecticides. An LC–MS/MS method was developed and validated for the simultaneous quantification of these three Carbamate Insecticides in the plasma of patients with acute intentional self-poisoning. Plasma samples were pretreated by acetonitrile for protein precipitation. Chromatography was carried out on a Luna C18(2) analytical column with gradient elution using a mobile phase containing acetonitrile and water with 10mM ammonium acetate. Mass spectrometric analysis was performed by an Applied Biosystems MDS Sciex API 2000 triple quadrupole mass spectrometer coupled with electrospray ionization (ESI) source in the positive ion mode. The total run time was 7min. The assay was validated over a concentration range from 10 to 1000ng/ml for CSN and FBC and 20–2000ng/ml for CFN. The precision and accuracy for both intra- and inter-day determination of all analytes were acceptable (<15%). No significant matrix effect was observed. Stability of compounds was established for short term bench and autosampler storage as well as freeze/thaw cycles. The method was effectively applied to 270 clinical samples from patients with a history of acute intentional Carbamate self-poisoning.
Xin Liu - One of the best experts on this subject based on the ideXlab platform.
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simultaneous quantification of Carbamate Insecticides in human plasma by liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2011Co-Authors: Ahmed Mostafa, Michael S. Roberts, Gregory Medley, Darren M Roberts, Mosaad S Mohamed, Abdalla A Elshanawani, Xin LiuAbstract:Carbofuran (CFN), carbosulfan (CSN) and fenobucarb (FBC) are Carbamate pesticides that are widely used in gardening and agriculture for the control of insects. Human poisoning due to occupational or self-poisoning exposures is also reported, so assays are required to quantify the plasma concentration of these Insecticides. An LC–MS/MS method was developed and validated for the simultaneous quantification of these three Carbamate Insecticides in the plasma of patients with acute intentional self-poisoning. Plasma samples were pretreated by acetonitrile for protein precipitation. Chromatography was carried out on a Luna C18(2) analytical column with gradient elution using a mobile phase containing acetonitrile and water with 10mM ammonium acetate. Mass spectrometric analysis was performed by an Applied Biosystems MDS Sciex API 2000 triple quadrupole mass spectrometer coupled with electrospray ionization (ESI) source in the positive ion mode. The total run time was 7min. The assay was validated over a concentration range from 10 to 1000ng/ml for CSN and FBC and 20–2000ng/ml for CFN. The precision and accuracy for both intra- and inter-day determination of all analytes were acceptable (<15%). No significant matrix effect was observed. Stability of compounds was established for short term bench and autosampler storage as well as freeze/thaw cycles. The method was effectively applied to 270 clinical samples from patients with a history of acute intentional Carbamate self-poisoning.
Sara Bogialli - One of the best experts on this subject based on the ideXlab platform.
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simple and rapid assay for analyzing residues of Carbamate Insecticides in bovine milk hot water extraction followed by liquid chromatography mass spectrometry
Journal of Chromatography A, 2004Co-Authors: Sara Bogialli, Roberta Curini, Antonio Di Corcia, Manuela Nazzari, Aldo Lagana, Michela TonciAbstract:A simple, specific and rapid procedure for determining six largely used Carbamate Insecticides in bovine whole milk is here presented. This method is based on the matrix solid-phase dispersion technique with heated water as extractant followed by liquid chromatography (LC)-mass spectrometry (MS) equipped with a single quadrupole and an electrospray ion source. Target compounds were extracted from milk by water heated at 90 degrees C. After acidification and filtration, 0.2 mL of the aqueous extract was injected in the LC column. MS data acquisition was performed in the selected ion-monitoring mode, selecting three ions for each target compound. Heated water appeared to be an excellent extractant, since absolute recovery data ranged between 76 and 104% with R.S.D. not larger than 8%. Using butocarboxim (an obsolete Carbamate insecticide) as surrogate internal standard, the accuracy of the analysis at three spike levels varied between 85 and 105% with R.S.D. not larger than 9%. On the basis of a signal-to-noise ratio of 10, limits of quantification were estimated to range between 3 ppb (propoxur) and 8 ppb (pirimicarb). The effects of temperature, volume and flow rate of the extractant on the analyte recovery were studied.
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A Simple and Rapid Assay for Analyzing Residues of Carbamate Insecticides in Vegetables and Fruits: Hot Water Extraction Followed by Liquid Chromatography-Mass Spectrometry
Journal of Agricultural and Food Chemistry, 2004Co-Authors: Sara Bogialli, Roberta Curini, Antonio Di Corcia, Manuela Nazzari, Davide TamburroAbstract:A simple, specific, and rapid analytical method for determining seven largely used Carbamate Insecticides in tomato, spinach, lettuce, zucchini, pear, and apple is here presented. This method is based on the matrix solid-phase dispersion technique, with heated water as extractant followed by liquid chromatography (LC)-mass spectrometry (MS) equipped with a single quadrupole and an electrospray ion source. Target compounds were extracted from the vegetal matrixes by water heated at 50 °C. After acidification and filtration, 0.25 mL of any aqueous extract was injected in the LC column. MS data acquisition was performed in the selected ion monitoring mode, selecting three ions for each target compound. Heated water appeared to be an excellent extractant because recovery data ranged between 76 (carbaryl in spinach) and 99% (pirimicarb in spinach), with RSDs not larger than 10%. Using trimethacarb (an obsolete Carbamate insecticide) as a surrogate internal standard, the accuracy of the analysis varied between ...
Ahmed Mostafa - One of the best experts on this subject based on the ideXlab platform.
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High lethality and minimal variation after acute self-poisoning with Carbamate Insecticides in Sri Lanka - implications for global suicide prevention.
Clinical Toxicology, 2016Co-Authors: Thomas Lamb, Liza R. Selvarajah, Fahim Mohamed, Shaluka Jayamanne, Indika Gawarammana, Ahmed Mostafa, Nicholas A. Buckley, Michael S. Roberts, Michael EddlestonAbstract:AbstractBackground: Highly hazardous organophosphorus (OP) Insecticides are responsible for most pesticide poisoning deaths. As they are removed from agricultural practice, they are often replaced by Carbamate Insecticides of perceived lower toxicity. However, relatively little is known about poisoning with these Insecticides.Methods: We prospectively studied 1288 patients self-poisoned with Carbamate Insecticides admitted to six Sri Lankan hospitals. Clinical outcomes were recorded for each patient and plasma Carbamate concentration measured in a sample to confirm the Carbamate ingested.Findings: Patients had ingested 3% carbofuran powder (719), carbosulfan EC25 liquid (25% w/v, 389), or fenobucarb EC50 liquid (50% w/v, 127) formulations, Carbamate Insecticides of WHO Toxicity Classes Ib, II, and II, respectively. Intubation and ventilation was required for 183 (14.2%) patients while 71 (5.5%) died. Compared with carbofuran, poisoning with carbosulfan or fenobucarb was associated with significantly highe...
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simultaneous quantification of Carbamate Insecticides in human plasma by liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2011Co-Authors: Ahmed Mostafa, Michael S. Roberts, Gregory Medley, Darren M Roberts, Mosaad S Mohamed, Abdalla A Elshanawani, Xin LiuAbstract:Carbofuran (CFN), carbosulfan (CSN) and fenobucarb (FBC) are Carbamate pesticides that are widely used in gardening and agriculture for the control of insects. Human poisoning due to occupational or self-poisoning exposures is also reported, so assays are required to quantify the plasma concentration of these Insecticides. An LC–MS/MS method was developed and validated for the simultaneous quantification of these three Carbamate Insecticides in the plasma of patients with acute intentional self-poisoning. Plasma samples were pretreated by acetonitrile for protein precipitation. Chromatography was carried out on a Luna C18(2) analytical column with gradient elution using a mobile phase containing acetonitrile and water with 10mM ammonium acetate. Mass spectrometric analysis was performed by an Applied Biosystems MDS Sciex API 2000 triple quadrupole mass spectrometer coupled with electrospray ionization (ESI) source in the positive ion mode. The total run time was 7min. The assay was validated over a concentration range from 10 to 1000ng/ml for CSN and FBC and 20–2000ng/ml for CFN. The precision and accuracy for both intra- and inter-day determination of all analytes were acceptable (<15%). No significant matrix effect was observed. Stability of compounds was established for short term bench and autosampler storage as well as freeze/thaw cycles. The method was effectively applied to 270 clinical samples from patients with a history of acute intentional Carbamate self-poisoning.
Darren M Roberts - One of the best experts on this subject based on the ideXlab platform.
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simultaneous quantification of Carbamate Insecticides in human plasma by liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2011Co-Authors: Ahmed Mostafa, Michael S. Roberts, Gregory Medley, Darren M Roberts, Mosaad S Mohamed, Abdalla A Elshanawani, Xin LiuAbstract:Carbofuran (CFN), carbosulfan (CSN) and fenobucarb (FBC) are Carbamate pesticides that are widely used in gardening and agriculture for the control of insects. Human poisoning due to occupational or self-poisoning exposures is also reported, so assays are required to quantify the plasma concentration of these Insecticides. An LC–MS/MS method was developed and validated for the simultaneous quantification of these three Carbamate Insecticides in the plasma of patients with acute intentional self-poisoning. Plasma samples were pretreated by acetonitrile for protein precipitation. Chromatography was carried out on a Luna C18(2) analytical column with gradient elution using a mobile phase containing acetonitrile and water with 10mM ammonium acetate. Mass spectrometric analysis was performed by an Applied Biosystems MDS Sciex API 2000 triple quadrupole mass spectrometer coupled with electrospray ionization (ESI) source in the positive ion mode. The total run time was 7min. The assay was validated over a concentration range from 10 to 1000ng/ml for CSN and FBC and 20–2000ng/ml for CFN. The precision and accuracy for both intra- and inter-day determination of all analytes were acceptable (<15%). No significant matrix effect was observed. Stability of compounds was established for short term bench and autosampler storage as well as freeze/thaw cycles. The method was effectively applied to 270 clinical samples from patients with a history of acute intentional Carbamate self-poisoning.