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Chemosphere Oct 2022Pirimicarb as a pesticide is used to control the aphids in the agriculture field; however, it affects the groundwater ecosystem by leaching through the soil profile. The...
Pirimicarb as a pesticide is used to control the aphids in the agriculture field; however, it affects the groundwater ecosystem by leaching through the soil profile. The post-synthetic amine and BWO modified MIL-100 (Fe) nanofillers were synthesized. The photocatalytic property of amine-functionalized and BWO@MIL-100(Fe) nanofillers was confirmed by the lesser bandgap energy than the unmodified MIL-100 (Fe) nanofiller. Herein, we constructed a nanofillers grafted PVDF membrane via in-situ polymerization technique for the pirimicarb reduction and photodegradation. Furthermore, the nanofiller's grafted membranes were characterized by FESEM, XRD, FTIR, and contact angle analysis. The carboxylic acid peak was observed on the FTIR which demonstrated the PAA grafted on the membrane surface and similar crystalline peaks evident that the nanofillers were grafted on the membrane surface. Furthermore, surface morphology studies have exhibited the dispersion of nanofillers and enhanced microvoids in the cross-section of the membrane. The decrease in the water contact angle of the membrane depicted the improved antifouling properties and surface energy. The nanofiller's grafted membranes have shown higher hydrophilicity correlated well with the enhanced pure water flux in the order M4 > M5 > M2 > M3 > M6 > M7 compared to the neat membrane (M1). In BWO@MIL-100(Fe) membrane has shown a higher permeate flux (25.99 L m.h) than the neat PVDF membrane. The BWO@MIL-100(Fe) grafted PVDF membrane has also shown excellent pirimicarb photodegradation of 81% at pH 5. The proposed MIL-100 (Fe) and bismuth tungsten nanocomposite will pave the way for the different MOF-based photocatalytic materials for membrane-based pesticide degradation.
Topics: Amines; Bismuth; Ecosystem; Fluorocarbon Polymers; Pesticides; Photolysis; Polymerization; Polyvinyls; Tungsten Compounds; Water
PubMed: 35690168
DOI: 10.1016/j.chemosphere.2022.135286 -
Archives of Toxicology Dec 2020In chemical risk assessment, default uncertainty factors are used to account for interspecies and interindividual differences, and differences in toxicokinetics and... (Comparative Study)
Comparative Study
Acetylcholinesterase inhibition in electric eel and human donor blood: an in vitro approach to investigate interspecies differences and human variability in toxicodynamics.
In chemical risk assessment, default uncertainty factors are used to account for interspecies and interindividual differences, and differences in toxicokinetics and toxicodynamics herein. However, these default factors come with little scientific support. Therefore, our aim was to develop an in vitro method, using acetylcholinesterase (AChE) inhibition as a proof of principle, to assess both interspecies and interindividual differences in toxicodynamics. Electric eel enzyme and human blood of 20 different donors (12 men/8 women) were exposed to eight different compounds (chlorpyrifos, chlorpyrifos-oxon, phosmet, phosmet-oxon, diazinon, diazinon-oxon, pirimicarb, rivastigmine) and inhibition of AChE was measured using the Ellman method. The organophosphate parent compounds, chlorpyrifos, phosmet and diazinon, did not show inhibition of AChE. All other compounds showed concentration-dependent inhibition of AChE, with ICs in human blood ranging from 0.2-29 µM and ICs ranging from 0.1-18 µM, indicating that AChE is inhibited at concentrations relevant to the in vivo human situation. The oxon analogues were more potent inhibitors of electric eel AChE compared to human AChE. The opposite was true for carbamates, pointing towards interspecies differences for AChE inhibition. Human interindividual variability was low and ranged from 5-25%, depending on the concentration. This study provides a reliable in vitro method for assessing human variability in AChE toxicodynamics. The data suggest that the default uncertainty factor of ~ 3.16 may overestimate human variability for this toxicity endpoint, implying that specific toxicodynamic-related adjustment factors can support quantitative in vitro to in vivo extrapolations that link kinetic and dynamic data to improve chemical risk assessment.
Topics: Acetylcholinesterase; Animals; Bayes Theorem; Biological Variation, Population; Cholinesterase Inhibitors; Dose-Response Relationship, Drug; Electrophorus; Female; GPI-Linked Proteins; Humans; Male; Proof of Concept Study; Reproducibility of Results; Risk Assessment; Species Specificity; Toxicity Tests; Toxicokinetics; Uncertainty
PubMed: 33037899
DOI: 10.1007/s00204-020-02927-8 -
Bioinformation 2014Glutathione S-transferases (GSTs) are one of the major families of detoxifying enzymes that detoxifies different chemical compounds including insecticides in different...
Glutathione S-transferases (GSTs) are one of the major families of detoxifying enzymes that detoxifies different chemical compounds including insecticides in different insect species. Among the GST subclasses, sigma GSTs are found to be the most abundant and conserved among different insect orders. These GSTs are found to play an important role in lipid peroxidation as well as detoxification. Cotton aphid, Aphis gossypii is the most damaging sucking pest with a wide range of hosts and vector of more than 50 plant viruses. Resistance to insecticides in A. gossypii is reported in India and in other countries. Glutathione S transferases (GSTs), an oxidative enzyme is understood to have a role in insecticide resistance and plant resistance breakdown. In relation to this, we have focused on the sigma 1 (GenBank Accession No: JN989964.1) and sigma 2 (GenBank Accession No: JN989965.1) GSTs of A. gossypii and their interaction with plant natural compounds and insecticides. Molecular screening of different insecticides (Chlorphinamidine, Mevinphos, Nitenpyrum, Piperonyl butoxide, Tetrachlorovinphos, Pyrethrins, Resmetrin, Pirimicarb and Dinotefuran) and known plant derived natural compounds (Catechin, Gossypol, Myrcene, Kaempferol, P-coumaric acid, Quercetin, Tannins, α-mangostin, Capsaicin, Cinnamic acid, Citronellal, Curcumin, Dicumarol, Ellagic acid, Eugenol, Geriniol, Isoeugenol, Juglone, Menadione, Methyl jasmonate, Morin, Myricetin, Myristicin, Piperine, Plumbagin, Tangitinin C, Thymol, Vanillin, Alpha pipene, α-terpineol Apigenin and β-Caryophyllene) with sigma 1 and sigma 2 GST protein models was completed using Maestro 9.3 (Schrodinger, USA). This exercise showed the binding of piperonyl butoxide with sigma 1 GST and tannin with sigma 2 GST for further consideration.
PubMed: 25512683
DOI: 10.6026/97320630010679 -
Bulletin of Environmental Contamination... Apr 2016Surface water sampling in 2007-2010 measured the occurrence of carbamates and metalaxyl during base flow conditions and wet weather events in southern Ontario surface...
Surface water sampling in 2007-2010 measured the occurrence of carbamates and metalaxyl during base flow conditions and wet weather events in southern Ontario surface waters. Carbaryl, metalaxyl and pirimicarb were the most frequently detected compounds. In 2008 these three compounds were detected in over 50 % of the samples. Overall mean concentrations of carbaryl and metalaxyl over the course of the study (2007-2010) were 15 and 18 ng/L, respectively. Elevated concentrations of carbaryl (~100 to ~950 ng/L) appeared associated with wet weather (high flow) events, while highest concentrations of metalaxyl (~20-1330 ng/L) were correlated with base flow conditions. We attributed these observations as the result of runoff of carbaryl from the watershed during rain events, while metalaxyl contamination may have resulted primarily from spray drift.
Topics: Alanine; Carbamates; Carbaryl; Environmental Monitoring; Fresh Water; Ontario; Pesticides; Pyrimidines; Rain; Water Pollutants, Chemical
PubMed: 26754544
DOI: 10.1007/s00128-015-1719-x -
Journal of Pharmaceutical and... Aug 2024Pesticides play an important role in forensic toxicology and are usually classified as a single class of chemicals. Despite their commonly perceived unity, pesticides...
Development and validation of a multi-substance method for routine analysis of pesticides in post-mortem samples by Ultra-High Performance Liquid Chromatography-Tandem Mass Spectrometry.
Pesticides play an important role in forensic toxicology and are usually classified as a single class of chemicals. Despite their commonly perceived unity, pesticides encompass a spectrum of compounds, including organophosphates, carbamates, pyrethroids or organochlorines, among others, each with varying degrees of toxicity. Pesticide analysis in post-mortem samples can be difficult due to the complexity of the samples and to the high toxicity of these compounds. The aim of this study was to develop and validate an easy to use, sensitive, and robust method, using ultra-performance liquid chromatography-tandem mass spectrometry to be incorporated in the routine flow for pesticide analysis in post-mortem blood samples. Described herein is a streamlined, expeditious, yet highly efficient method facilitating the screening, qualitative assessment, and quantitative confirmation of 15 pesticides, including acetamiprid, azinphos-ethyl, bendiocarb, carbofuran, chlorfenvinphos, dimethoate, imidaclopride, malathion, methiocarb, methomyl, parathion, pirimicarb, strychnine, tetrachlorvinphos, and thiacloprid in post-mortem blood, recognizing the pivotal role blood plays in forensic investigations. The developed method was linear from 10 to 200 ng/mL; limits of detection were between 1 and 10 ng/mL, depending on the compound; it was successfully evaluated a dilution ratio of 1-2, 5 and 10; and 8 substances showed maximum stability for the time interval studied. This UHPLC-MS/MS method is useful and a powerful tool in a toxicology lab because it is fast, simple, effective, and trustworthy. The results of this validation highlight the robustness of the analytical method, providing a valuable tool for the accurate and sensitive detection of pesticides in post-mortem blood. Poised for routine implementation, this method has already found success in suspected intoxication cases, promising to elevate the standards of forensic pesticide analysis.
Topics: Tandem Mass Spectrometry; Chromatography, High Pressure Liquid; Humans; Pesticides; Forensic Toxicology; Reproducibility of Results; Autopsy; Limit of Detection
PubMed: 38701535
DOI: 10.1016/j.jpba.2024.116176 -
Journal of Chromatography. B,... Jun 2023Carbamate pesticides are extensively used in agriculture for their inhibition to acetylcholinesterase and damages to the insects' neural systems. Because of their...
A retrospective screening method for carbamate toxicant exposure based on butyrylcholinesterase adducts in human plasma with ultra-high performance liquid chromatography-tandem mass spectrometry.
Carbamate pesticides are extensively used in agriculture for their inhibition to acetylcholinesterase and damages to the insects' neural systems. Because of their toxicity, human poisoning incidents caused by carbamate pesticide exposure have occurred from time to time. What's more, some lethally toxic carbamate toxicants known as carbamate nerve agents (CMNAs) have been supplemented in Schedule 1 of the Annex on Chemicals in the Chemical Weapons Convention (CWC) by Organisation of the Prohibition of Chemical Weapons (OPCW) from 2020. And some other carbamates, like physostigmine, have been used in clinical treatment as anticholinergic drugs and their misuse may also cause damages to the body. Similar to organophosphorus toxicants, carbamate toxicants would react with butyrylcholinesterase (BChE) in plasma when entering the human body, resulting in the BChE adducts, based on which the exposure of carbamate toxicants could be detected retrospectively. In this study, methylcarbamyl nonapeptide and dimethylcarbamyl nonapeptide from pepsin digestion of BChE adducts were identified with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) in product ion scan mode. Carbofuran was chosen as the target to establish the detection method of carbamate toxicant exposure based on methylcarbamyl nonapeptide digested from methylcarbamyl BChE. Procainamide-gel affinity purification, pepsin digestion and UHPLC-MS/MS analysis in multiple reaction monitoring (MRM) mode were applied. Under the optimized conditions of sample preparation and UHPLC-MS/MS MRM analysis, the limits of detection (LODs) reached 10.0 ng/mL of plasma exposed to carbofuran with satisfactory specificity. The quantitation approach was established with d-carbofuran-exposed plasma as the internal standard (IS) and the linearity range was 30.0-1.00 × 10 nmol/L (R >0.998) with the accuracy of 95.6%-107% and precision of ≤9% relative standard deviation (RSD). The applicability was also evaluated by N,N-dimethyl-carbamates with the LODs of 30.0 nmol/L for pirimicarb-exposed plasma based on dimethylcarbamyl nonapeptide. Because most of carbamate toxicants has methylcarbamyl or dimethylcarbamyl groups, this approach could be applied on the retrospective screening of carbamate toxicant exposure including CMNAs, carbamate pesticides or carbamate drugs. This study could provide an effective means in the fields of CWC verification, toxicological mechanism investigation and down-selection of potential treatment options.
Topics: Humans; Butyrylcholinesterase; Chromatography, High Pressure Liquid; Tandem Mass Spectrometry; Retrospective Studies; Carbofuran; Acetylcholinesterase; Pepsin A; Nerve Agents; Pesticides
PubMed: 37285767
DOI: 10.1016/j.jchromb.2023.123775 -
Environmental Science and Pollution... May 2016Different strategies are now being optimized to prevent water from agricultural areas being contaminated by pesticides. The aim of this work was to optimize the...
Different strategies are now being optimized to prevent water from agricultural areas being contaminated by pesticides. The aim of this work was to optimize the adsorption of non-polar (tebuconazole, triadimenol) and polar (cymoxanil, pirimicarb) pesticides by soils after applying the biosorbent spent mushroom substrate (SMS) at different rates. The adsorption isotherms of pesticides by three soils and SMS-amended soils were obtained and the adsorption constants were calculated. The distribution coefficients (K d) increased 1.40-23.1 times (tebuconazole), 1.08-23.7 times (triadimenol), 1.31-42.1 times (cymoxanil), and 0.55-23.8 times (pirimicarb) for soils amended with biosorbent at rates between 2 and 75 %. Increasing the SMS rates led to a constant increase in adsorption efficiency for non-polar pesticides but not for polar pesticides, due to the increase in the organic carbon (OC) content of soils as indicated by K OC values. The OC content of SMS-amended soils accounted for more than 90 % of the adsorption variability of non-polar pesticides, but it accounted for only 56.3 % for polar pesticides. The estimated adsorption of SMS-amended soils determined from the individual adsorption of soils and SMS was more consistent with real experimental values for non-polar pesticides than for polar pesticides. The results revealed the use of SMS as a tool to optimize pesticide adsorption by soils in dealing with specific contamination problems involving these compounds.
Topics: Adsorption; Agaricales; Agriculture; Pesticides; Soil; Soil Pollutants; Triazoles; Water Pollution
PubMed: 26832876
DOI: 10.1007/s11356-016-6132-4 -
The Science of the Total Environment Feb 2019In arid and semi-arid areas the use of treated wastewater for crop irrigation and other agricultural practices, such as the use of pesticides, increase the number of...
In arid and semi-arid areas the use of treated wastewater for crop irrigation and other agricultural practices, such as the use of pesticides, increase the number of emerging contaminants (ECs) in crops. Hazards of these practices to human being are largely unknown since there are few studies yet covering a short range of compounds and most of them under non-realistic conditions. This study aims at assessing this problem that will become global soon in an area of Saudi Arabia heavily affected by the reuse of treated wastewater and pesticide in order to ascertain its scale. The novelty of the study relays in the large number of ECs covered and the variety of crops (cabbage, barley, green beans, eggplants, chili, tomato and zucchini) analysed. Extraction procedure developed provided an appropriate extraction yield (up to 50% of the compounds were recovered within a 70-120% range), with good repeatability (relative standard deviations below 20% in most cases) and sensitivity (LOQ < 25 ng g) for the model compounds. Determination by liquid chromatography quadrupole time-of-flight (LC-QqTOF-MS) is able to identify >2000 contaminants. Sixty-four ECs were identified in wastewater but of the sixty-four compounds, six pharmaceuticals (atenolol, caffeine, carbamazepine and its metabolites 10,11-epoxycarbamazepine, gemfibrozil, and naproxen) and seven pesticides (acetamiprid, atrazine deethyl, azoxystrobin, bupirimate, diazinon, malathion, pirimicarb and some of their metabolites) were detected in plants. Furhermore, one metabolite of the ibuprofen (not detected in water or soil), the ibuprofen hexoside was also found in plants. Up to our knowledge, this study demonstrate for the first time the accumulation of ECs in crops irrigated with treated wastewater under real non-controlled environmental conditions.
Topics: Agricultural Irrigation; Crops, Agricultural; Environmental Monitoring; Saudi Arabia; Soil; Soil Pollutants; Waste Disposal, Fluid; Wastewater; Water Pollutants, Chemical
PubMed: 30368185
DOI: 10.1016/j.scitotenv.2018.10.224 -
Environmental Science and Pollution... Jan 2017The high amount of winery wastewaters produced each year makes their treatment a priority issue due to their problematic characteristics such as acid pH, high...
The high amount of winery wastewaters produced each year makes their treatment a priority issue due to their problematic characteristics such as acid pH, high concentration of organic load and colourful compounds. Furthermore, some of these effluents can have dissolved pesticides, due to the previous grape treatments, which are recalcitrant to conventional treatments. Recently, photo-electro-Fenton process has been reported as an effective procedure to mineralize different organic contaminants and a promising technology for the treatment of these complex matrixes. However, the reactors available for applying this process are scarce and they show several limitations. In this study, a sequential two-column reactor for the photo-electro-Fenton treatment was designed and evaluated for the treatment of different pesticides, pirimicarb and pyrimethanil, used in wine production. Both studied pesticides were efficiently removed, and the transformation products were determined. Finally, the treatment of a complex aqueous matrix composed by winery wastewater and the previously studied pesticides was carried out in the designed sequential reactor. The high removals of TOC and COD reached and the low energy consumption demonstrated the efficiency of this new configuration.
Topics: Hydrogen Peroxide; Industrial Waste; Iron; Pesticides; Photolysis; Vitis; Waste Disposal, Fluid; Water Purification; Wine
PubMed: 27796998
DOI: 10.1007/s11356-016-7937-x -
Journal of Agricultural and Food... Apr 2020The goal of this study was to perform in silico identification of bioinsecticidal potential of 42 monoterpenes against and Snyder. Quantitative structure-activity...
The goal of this study was to perform in silico identification of bioinsecticidal potential of 42 monoterpenes against and Snyder. Quantitative structure-activity relationship (QSAR) modeling was performed for both organisms, while docking and molecular dynamics were used only for . Neryl acetate has the lowest interaction energy (-87 kcal/mol) against active site of acetylcholinesterase, which is comparable to the ones of methiocarb and pirimicarb (-90 kcal/mol) and reported PDB binder 9-(3-iodobenzylamino)-1,2,3,4-tetrahydroacridine (-112.67 kcal/mol). Interaction stability was verified by molecular dynamics simulations and showed that the stability of ACHE active site complexes with three selected terpenes is comparable to the one of the pirimicarb and methiocarb. Overall, our results suggest that pulegone, citronellal, carvacrol, linalyl acetate, neryl acetate, citronellyl acetate, and geranyl acetate may be considered as a potential pesticide candidates.
Topics: Acetylcholinesterase; Animals; Drosophila melanogaster; Insect Proteins; Insecticides; Isoptera; Molecular Docking Simulation; Molecular Dynamics Simulation; Monoterpenes; Quantitative Structure-Activity Relationship
PubMed: 32251592
DOI: 10.1021/acs.jafc.0c00272