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Angelo Abbondandolo - One of the best experts on this subject based on the ideXlab platform.
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genotoxic effects of the carbamate insecticide Methomyl i in vitro studies with pure compound and the technical formulation lannate 25
Environmental and Molecular Mutagenesis, 1994Co-Authors: Stefania Bonatti, Claudia Bolognesi, Paolo Degan, Angelo AbbondandoloAbstract:The carbamate insecticide Methomyl and the Methomyl-containing technical formulation "Lannate 25" were tested on whole blood human lymphocyte cultures. Both products induced dose-dependent increases in chromosome aberrations and micronuclei. Lannate 25 induced DNA damage as measured by the alkaline elution assay and hydroxylation of guanine at the C8 position. Sister chromatid exchanges were not increased significantly with either product. Overall, the technical formulation was more active than the pure compound, when compared at similar concentrations of active principle. Moreover, a different ratio of CREST-positive/CREST-negative micronuclei was observed with the two products, pure Methomyl being relatively more active than Lannate 25 in the induction of CREST-positive micronuclei. On the basis of these results, previous evaluations of Methomyl as a nongenotoxic compound should be reconsidered.
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genotoxic effects of the carbamate insecticide Methomyl i in vitro studies with pure compound and the technical formulation lannate 25
Environmental and Molecular Mutagenesis, 1994Co-Authors: Stefania Bonatti, Claudia Bolognesi, Paolo Degan, Angelo AbbondandoloAbstract:The carbamate insecticide, Methomyl, and the Methomyl-containing technical formulation, "Lannate 25", were tested for the induction of DNA damage in vivo. Swiss CD1 mice were treated intraperitoneally with test substances and the following tests were performed: alkaline elution of liver and kidney DNA, 8-hydroxyguanosine detection in liver DNA, and 32P-postlabelling analysis of DNA adducts in liver DNA. The clastogenic activity of the two pesticide preparations was also evaluated as micronucleus frequency in bone marrow. No DNA adducts were detected in liver DNA of mice treated with pure Methomyl, while a dose-related increase in DNA adducts was found in Lannate 25-treated animals. All other tests were positive with both Methomyl and Lannate 25. A summary of genotoxic activity of Methomyl is also presented. The hypothesis that the observed genotoxic effects of Methomyl are induced indirectly, through formation of active oxygen species, is discussed.
Jia Zhang Chen - One of the best experts on this subject based on the ideXlab platform.
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determination of Methomyl residues in bohe by ultrahigh performance liquid chromatography tandem mass spectrometry uplc ms
International Journal of Analytical Chemistry, 2020Co-Authors: Jia Zhang Chen, Li Ping Qiu, Yao Zheng, Addotey Tracy Naa Adoley, Benkhelifa FatehAbstract:The aim of this work is to investigate the presence of Methomyl pesticide residue and the rate of disappearance in mint cultivated in the aquaponics system based on the application of UPLC-MS to establish a safety time interval before crop harvesting. Results showed that an effective and sensitive method based on UPLC-MS has been used for the determination of Methomyl pesticide residues in mint. The initial residue level was much higher in roots (79.52 μg/kg), and it can be decreased to 16.73 (after 15 days) μg/kg and 3.31 (20 days) μg/kg, while the least was detected on the mix leaves and stems (44.54 μg/kg), and it can be decreased to 15.35 (after 20 days). In our case, we suggest that a safety interval in the range of 15-20 days should be allowed after the detection of Methomyl in water, and the concentration of Methomyl was lower than the acceptable daily intake (ADI) of the China Food and Drug Administration (CFDA) (20 μg/kg).
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effect of chronic exposure to Methomyl on tissue damage and apoptosis in testis of tilapia oreochromis niloticus and recovery pattern
Bulletin of Environmental Contamination and Toxicology, 2019Co-Authors: Shun Long Meng, Jia Zhang Chen, Li Min Fan, Chao Song, Li Ping Qiu, Tao Liu, Xi Chen, Yao ZhengAbstract:Tilapia were exposed to 0, 0.2, 2, 20, 200 µg/L Methomyl for 30 days, and then transferred to Methomyl-free water for 18 days. Caspase-8 in serum, apoptosis rate, microstructure and ultra-microstructure of testis were checked after Methomyl exposure and at 18 days after transferring to Methomyl-free water. There were no significant changes in Caspase-8 activity, apoptosis rate, and tissue structure in testis exposed to 0.2 and 2 µg/L compared with control. However, when tilapia exposed to 20 and 200 µg/L, the Caspase-8 activity and apoptosis rate were induced significantly, and tissue damage happened compared with the control. Thus it would appear 2 µg/L Methomyl might be considered as the no observed adverse effect level. Recovery data showed that the effects produced by lower concentration of 20 µg/L were reversible but not at the higher 200 µg/L concentration.
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effect of Methomyl on sex steroid hormone and vitellogenin levels in serum of male tilapia oreochromis niloticus and recovery pattern
Environmental Toxicology, 2017Co-Authors: Shun Long Meng, Li Min Fan, Chao Song, Li Ping Qiu, Yao Zheng, Jia Zhang ChenAbstract:Tilapia were exposed to sub-lethal concentrations of 0, 0.2, 2, 20 or 200 μg/L for 30 days, then transferred to Methomyl-free water for 18 days. E2 , T, 11-KTand VTG in serum were examined. There were no significant changes in all the parameters in serum of tilapia exposed to 0.2 μg/L and 2 μg/L Methomyl compared to the control. However, 20 μg/L and 200 μg/L have the potential to disrupt the endocrine system of male tilapia, as shown by its ability to increase VTG and E2 and decrease T and 11-KT in serum. Thus it would appear the no observed adverse effect level for sexual steroid hormones of Methomyl is lower than 2 μg/L. Recovery data showed that the effects produced by 20μg/L were reversible but not at 200μg/L. Furthermore, the sensitivity of above parameters to Methomyl followed the order of VTG>E2 >11-KT>T>GSI, suggesting VTG being the better biomarkers.
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effects of Methomyl on steroidogenic gene transcription of the hypothalamic pituitary gonad liver axis in male tilapia
Chemosphere, 2016Co-Authors: Shun Long Meng, Li Min Fan, Chao Song, Li Ping Qiu, Yao Zheng, Jia Zhang ChenAbstract:Male tilapia were exposed to sub-lethal Methomyl concentrations of 0, 0.2, 2, 20 or 200 μg/L for 30 d, and were subsequently cultured in Methomyl-free water for 18 d. Relative transcript abundance of steroidogenic genes involved in the HPGL axis of male tilapia was examined at 30 d in the exposure test and at 18 d in the recovery test. The results revealed that low concentrations of Methomyl (0.2 and 2 μg/L) did not cause significant changes in gene mRNA levels in the HPGL axis of male tilapia; thus, we considered 2 μg/L concentrations as the level that showed no apparent adverse endocrine disruption effects. However, higher concentrations of Methomyl (20 and 200 μg/L) disrupted the endocrine system and caused significant increase in the levels of GnRH2, GnRH3, ERα, and ERβ genes in the hypothalamus, GnRHR and FSHβ genes in the pituitary, CYP19a, FSHR, and ERα genes in the testis, and VTG and ERα genes in the liver, and significantly decreased the levels of LHR, StAR, 3β-HSD, and ARα genes in the testis and LHβ gene in the pituitary, leading to changes in sex steroid hormone and vitellogenin levels in the serum and ultimately resulting in reproductive dysfunction in male tilapia. The recovery tests showed that the toxicity effect caused by 20 μg/L Methomyl was reversible; however, the toxicity effect at 200 μg/L of Methomyl was irreversible after 18 d. Therefore, we concluded that 200 μg/L was the threshold concentration for Methomyl-induced irreversible endocrine disruption in male tilapia.
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effects of chronic exposure of Methomyl on the antioxidant system in liver of nile tilapia oreochromis niloticus
Ecotoxicology and Environmental Safety, 2014Co-Authors: Shun Long Meng, Jia Zhang Chen, Li Min Fan, Chao Song, Li Ping QiuAbstract:Abstract The chronic effect of Methomyl on the antioxidant system in tilapia ( Oreochromis niloticus ) was investigated. Fish were exposed to sub-lethal concentrations of 0.2, 2, 20 and 200 μ gL −1 for 30 days, and then transferred to Methomyl-free water for 18 days. Hepatic antioxidant parameters, including Glutathione-S-transferase (GST), Glutathione peroxidase (GPx), Glutathione reductase (GR), Reduced glutathione (GSH) and oxidized glutathione (GSSG), were measured at 10 min (day 0), 6, 12, 18, 24 and 30 days after starting the experiment and at 18 days after transferring to Methomyl-free water. There were no significant changes in enzymatic activity and content of antioxidants in liver of tilapia exposed to 0.2 μg L −1 Methomyl compared to controls. However, the results showed significant increases in activities of GST, GR, GPx and levels of GSSG accompanied by a decrease in GSH levels following Methomyl exposure in tilapia to 2, 20 or 200 μg L −1 over the 30-day exposure period and the highest induction rates in GST, GR, GPx and GSSG were 150.87%, 163.21%, 189.76%, and 179.56% of the control respectively, and the highest inhibition rate in GSH was 50.67% of the control, suggesting the presence of oxidative stress. Thus it would appear that the 0.2 μg L −1 Methomyl might be considered as the no observed adverse effect level (NOAEL). Recovery data showed that the effects produced by lower concentration of Methomyl 20 μg L −1 were reversible but not at the higher 200 μg L −1 concentration.
Shun Long Meng - One of the best experts on this subject based on the ideXlab platform.
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effect of chronic exposure to Methomyl on tissue damage and apoptosis in testis of tilapia oreochromis niloticus and recovery pattern
Bulletin of Environmental Contamination and Toxicology, 2019Co-Authors: Shun Long Meng, Jia Zhang Chen, Li Min Fan, Chao Song, Li Ping Qiu, Tao Liu, Xi Chen, Yao ZhengAbstract:Tilapia were exposed to 0, 0.2, 2, 20, 200 µg/L Methomyl for 30 days, and then transferred to Methomyl-free water for 18 days. Caspase-8 in serum, apoptosis rate, microstructure and ultra-microstructure of testis were checked after Methomyl exposure and at 18 days after transferring to Methomyl-free water. There were no significant changes in Caspase-8 activity, apoptosis rate, and tissue structure in testis exposed to 0.2 and 2 µg/L compared with control. However, when tilapia exposed to 20 and 200 µg/L, the Caspase-8 activity and apoptosis rate were induced significantly, and tissue damage happened compared with the control. Thus it would appear 2 µg/L Methomyl might be considered as the no observed adverse effect level. Recovery data showed that the effects produced by lower concentration of 20 µg/L were reversible but not at the higher 200 µg/L concentration.
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effect of Methomyl on sex steroid hormone and vitellogenin levels in serum of male tilapia oreochromis niloticus and recovery pattern
Environmental Toxicology, 2017Co-Authors: Shun Long Meng, Li Min Fan, Chao Song, Li Ping Qiu, Yao Zheng, Jia Zhang ChenAbstract:Tilapia were exposed to sub-lethal concentrations of 0, 0.2, 2, 20 or 200 μg/L for 30 days, then transferred to Methomyl-free water for 18 days. E2 , T, 11-KTand VTG in serum were examined. There were no significant changes in all the parameters in serum of tilapia exposed to 0.2 μg/L and 2 μg/L Methomyl compared to the control. However, 20 μg/L and 200 μg/L have the potential to disrupt the endocrine system of male tilapia, as shown by its ability to increase VTG and E2 and decrease T and 11-KT in serum. Thus it would appear the no observed adverse effect level for sexual steroid hormones of Methomyl is lower than 2 μg/L. Recovery data showed that the effects produced by 20μg/L were reversible but not at 200μg/L. Furthermore, the sensitivity of above parameters to Methomyl followed the order of VTG>E2 >11-KT>T>GSI, suggesting VTG being the better biomarkers.
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effects of Methomyl on steroidogenic gene transcription of the hypothalamic pituitary gonad liver axis in male tilapia
Chemosphere, 2016Co-Authors: Shun Long Meng, Li Min Fan, Chao Song, Li Ping Qiu, Yao Zheng, Jia Zhang ChenAbstract:Male tilapia were exposed to sub-lethal Methomyl concentrations of 0, 0.2, 2, 20 or 200 μg/L for 30 d, and were subsequently cultured in Methomyl-free water for 18 d. Relative transcript abundance of steroidogenic genes involved in the HPGL axis of male tilapia was examined at 30 d in the exposure test and at 18 d in the recovery test. The results revealed that low concentrations of Methomyl (0.2 and 2 μg/L) did not cause significant changes in gene mRNA levels in the HPGL axis of male tilapia; thus, we considered 2 μg/L concentrations as the level that showed no apparent adverse endocrine disruption effects. However, higher concentrations of Methomyl (20 and 200 μg/L) disrupted the endocrine system and caused significant increase in the levels of GnRH2, GnRH3, ERα, and ERβ genes in the hypothalamus, GnRHR and FSHβ genes in the pituitary, CYP19a, FSHR, and ERα genes in the testis, and VTG and ERα genes in the liver, and significantly decreased the levels of LHR, StAR, 3β-HSD, and ARα genes in the testis and LHβ gene in the pituitary, leading to changes in sex steroid hormone and vitellogenin levels in the serum and ultimately resulting in reproductive dysfunction in male tilapia. The recovery tests showed that the toxicity effect caused by 20 μg/L Methomyl was reversible; however, the toxicity effect at 200 μg/L of Methomyl was irreversible after 18 d. Therefore, we concluded that 200 μg/L was the threshold concentration for Methomyl-induced irreversible endocrine disruption in male tilapia.
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effects of chronic exposure of Methomyl on the antioxidant system in liver of nile tilapia oreochromis niloticus
Ecotoxicology and Environmental Safety, 2014Co-Authors: Shun Long Meng, Jia Zhang Chen, Li Min Fan, Chao Song, Li Ping QiuAbstract:Abstract The chronic effect of Methomyl on the antioxidant system in tilapia ( Oreochromis niloticus ) was investigated. Fish were exposed to sub-lethal concentrations of 0.2, 2, 20 and 200 μ gL −1 for 30 days, and then transferred to Methomyl-free water for 18 days. Hepatic antioxidant parameters, including Glutathione-S-transferase (GST), Glutathione peroxidase (GPx), Glutathione reductase (GR), Reduced glutathione (GSH) and oxidized glutathione (GSSG), were measured at 10 min (day 0), 6, 12, 18, 24 and 30 days after starting the experiment and at 18 days after transferring to Methomyl-free water. There were no significant changes in enzymatic activity and content of antioxidants in liver of tilapia exposed to 0.2 μg L −1 Methomyl compared to controls. However, the results showed significant increases in activities of GST, GR, GPx and levels of GSSG accompanied by a decrease in GSH levels following Methomyl exposure in tilapia to 2, 20 or 200 μg L −1 over the 30-day exposure period and the highest induction rates in GST, GR, GPx and GSSG were 150.87%, 163.21%, 189.76%, and 179.56% of the control respectively, and the highest inhibition rate in GSH was 50.67% of the control, suggesting the presence of oxidative stress. Thus it would appear that the 0.2 μg L −1 Methomyl might be considered as the no observed adverse effect level (NOAEL). Recovery data showed that the effects produced by lower concentration of Methomyl 20 μg L −1 were reversible but not at the higher 200 μg L −1 concentration.
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hepatic antioxidant enzymes sod and cat of nile tilapia oreochromis niloticus in response to pesticide Methomyl and recovery pattern
Bulletin of Environmental Contamination and Toxicology, 2014Co-Authors: Shun Long Meng, Jia Zhang Chen, Li Min Fan, Chao Song, Li Ping QiuAbstract:Hepatic antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) of Nile tilapia in response to pesticide Methomyl and recovery pattern were researched by exposing tilapia to sub-lethal Methomyl concentrations of 0, 0.2, 2, 20 and 200 μg/L for 30 days, and then transferred to Methomyl-free water for 18 days. Hepatic SOD and CAT were measured at 10 min (day 0), 6, 12, 18, 24 and 30 days after starting the experiment and at 18 days after transferring to Methomyl-free water. The results showed hepatic SOD and CAT activities in 2, 20 and 200 μg/L groups were affected significantly, however, that in 0.2 μg/L group didn’t change significantly compared to control during 30-day exposure period. Thus it would appear the 0.2 μg/L Methomyl might be considered the no observed adverse effect level. Recovery data showed that, for SOD, the effects produced by lower concentration of Methomyl 2 μg/L were reversible but not at concentrations higher than 20 μg/L, however, for CAT, the effects produced by all the concentrations were reversible.
Stefania Bonatti - One of the best experts on this subject based on the ideXlab platform.
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genotoxic effects of the carbamate insecticide Methomyl i in vitro studies with pure compound and the technical formulation lannate 25
Environmental and Molecular Mutagenesis, 1994Co-Authors: Stefania Bonatti, Claudia Bolognesi, Paolo Degan, Angelo AbbondandoloAbstract:The carbamate insecticide Methomyl and the Methomyl-containing technical formulation "Lannate 25" were tested on whole blood human lymphocyte cultures. Both products induced dose-dependent increases in chromosome aberrations and micronuclei. Lannate 25 induced DNA damage as measured by the alkaline elution assay and hydroxylation of guanine at the C8 position. Sister chromatid exchanges were not increased significantly with either product. Overall, the technical formulation was more active than the pure compound, when compared at similar concentrations of active principle. Moreover, a different ratio of CREST-positive/CREST-negative micronuclei was observed with the two products, pure Methomyl being relatively more active than Lannate 25 in the induction of CREST-positive micronuclei. On the basis of these results, previous evaluations of Methomyl as a nongenotoxic compound should be reconsidered.
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genotoxic effects of the carbamate insecticide Methomyl i in vitro studies with pure compound and the technical formulation lannate 25
Environmental and Molecular Mutagenesis, 1994Co-Authors: Stefania Bonatti, Claudia Bolognesi, Paolo Degan, Angelo AbbondandoloAbstract:The carbamate insecticide, Methomyl, and the Methomyl-containing technical formulation, "Lannate 25", were tested for the induction of DNA damage in vivo. Swiss CD1 mice were treated intraperitoneally with test substances and the following tests were performed: alkaline elution of liver and kidney DNA, 8-hydroxyguanosine detection in liver DNA, and 32P-postlabelling analysis of DNA adducts in liver DNA. The clastogenic activity of the two pesticide preparations was also evaluated as micronucleus frequency in bone marrow. No DNA adducts were detected in liver DNA of mice treated with pure Methomyl, while a dose-related increase in DNA adducts was found in Lannate 25-treated animals. All other tests were positive with both Methomyl and Lannate 25. A summary of genotoxic activity of Methomyl is also presented. The hypothesis that the observed genotoxic effects of Methomyl are induced indirectly, through formation of active oxygen species, is discussed.
Dusan ž Mijin - One of the best experts on this subject based on the ideXlab platform.
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photolysis of insecticide Methomyl in various solvents an experimental and theoretical study
Journal of Photochemistry and Photobiology A-chemistry, 2020Co-Authors: Anđelka Tomasevic, Dusan ž Mijin, Marina Radisic, Nevena ž Prlainovic, Ilija N Cvijetic, Danijela V Kovacevic, Aleksandar D MarinkovicAbstract:Abstract This study describes photolysis of 1 × 10–4 M Methomyl solution in deionized water and in eleven organic solvents, both polar and nonpolar: methanol, ethanol, n-propanol, isopropanol, sec-butanol, tert-butanol, isobutanol, isopentanol, n-hexane, acetonitrile, and dichloromethane. Photolysis of Methomyl at 254 nm was performed using Osram mercury lamp (6 × 8 W) by exposing to irradiation for five hours. All photolytic Methomyl reactions were studied by UV/Vis spectroscopy within a wavelength range of 190−300 nm (Spectrum Mode), and at 233.4 nm (Quantitative Mode), while the rate of photodecomposition of Methomyl was measured using UV spectroscopy and HPLC. In order to get better insight in the photolysis of Methomyl, a liquid chromatography-mass spectrometry (LC–MSn) was used. The rate of Methomyl photolysis was solvent-specific and the following reaction rate order was established: deionized water > tert-butanol > n-hexane > sec-butanol > ethanol > isopentanol > isobutanol > isopropanol > methanol > acetonitrile > dichloromethane > n-propanol. Both nonspecific and specific solvent-solute interactions contribute mutually to the differences in the obtained quantum yields. Results of quantum chemical calculations, using CBS-QB3 method, provided insights into the solvent effects on both ground and excited state. The LC/MSn analysis showed the formation of several photolytic products.
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the influence of polychromatic light on Methomyl degradation in tio2 and zno aqueous suspension
Desalination and Water Treatment, 2014Co-Authors: Anđelka Tomasevic, Dusan ž Mijin, Slavica Gasic, Ernő E KissAbstract:AbstractThe photocatalytic degradation of the insecticide Methomyl in water using TiO2 Merck Eusolex® T (anatase) under Osram ultra-vitalux® lamp light (315–400 nm, 300 W) was studied. The effect of the operational parameters, such as initial concentration of catalyst, initial Methomyl concentration, initial salt concentration (NaCl), and pH, was studied. The optimal concentration of catalyst was found to be 2.0 g/L. Using the Langmuir–Hinshelwood mechanism as a base, a pseudo-first-order kinetic model was illustrated and the adsorption equilibrium constant and the rate constant of the surface reaction were calculated (KMT = 0.079 L/mg and kC = 0.134 mg/L min, respectively). The photodegradation rate was higher in acidic than in alkaline conditions. The presence of Cl– ions significantly affected the photodegradation of the pollutant. The rate of photodecomposition of Methomyl was measured using UV spectroscopy and high performance liquid chromatography, while its mineralization was followed using ion chr...
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a kinetics study of the Methomyl electrochemical degradation in the chloride containing solutions
Applied Catalysis B-environmental, 2014Co-Authors: Branimir N Grgur, Dusan ž MijinAbstract:Abstract The kinetics of the electrochemical degradation of Methomyl has been study by the means of electrochemical techniques, UV–vis spectrophotometry, HPLC, and HPLC–ESI-MS in the sodium chloride containing solution. Degradation kinetics has been investigated on the DSA Ti/RuO 2 electrode in mainly 2 g dm −3 sodium chloride solution, applying the currents in the range of 10–90 mA and Methomyl concentration from 0.05 to 0.5 mM. It has been suggested that Methomyl degradation initially follows the pseudo zero-order Langmuir–Hinshelwood reaction kinetics, and mixed homogeneous and heterogeneous pseudo first-order reaction during prolonged electrolysis.
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study on the photocatalytic degradation of insecticide Methomyl in water
Desalination, 2010Co-Authors: Andjelka Tomasevic, Slobodan D Petrovic, Ernő E Kiss, Dusan ž MijinAbstract:Photo-Fenton degradation of the insecticide Methomyl in water using Fe-ZSM-5 zeolite and AlFe-pillared montmorillonite catalysts under halogen lamp light was studied. The study was performed at room temperature in a glass batch reactor under constant airflow. Both catalysts exhibited activity in the wet oxidative degradation of Methomyl. The rate of photodecomposition of Methomyl was measured using UV spectrometry and HPLC, while its mineralization was followed using ion chromatography (IC) and total organic carbon (TOC) analyzer. IC results showed that mineralization led to formation of sulfate, nitrate and ammonium ions during the process. Under our conditions, complete disappearance of 16.22 mg/L of pure pesticide and 100% or 80% TOC removal occurred within 4 h using 5 g/L or 1 g/L of Fe-ZSM-5 zeolite, respectively. The Fe-ZSM-5 was found to be a better catalyst. Pseudo-first-order rate constants were calculated, and the performed treatments compared.
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photochemical behavior of the insecticide Methomyl under different conditions
Separation Science and Technology, 2010Co-Authors: Andjelka Tomasevic, Dusan ž Mijin, Ernő E KissAbstract:This article describes the photolytic and photocatalytic removal of the insecticide Methomyl at low concentration from different types of water, upon UV, visible or natural solar light radiation, in the presence of TiO2 and ZnO, as well as using Fe-ZSM-5 zeolite and AlFe-pillared montmorillonite (photo-Fenton process). The rate of photodecomposition of Methomyl was measured using UV spectrometry and HPLC, while its mineralization was investigated by ion chromatography (IC) and total organic carbon (TOC) analysis. The photochemical removal of Methomyl is a natural and applicable model for the purification of water.