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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 -
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 -
Environmental Toxicology and Chemistry Nov 2020In surface waters, the illumination of photoactive engineered nanomaterials (ENMs) with ultraviolet (UV) light triggers the formation of reactive intermediates,...
In surface waters, the illumination of photoactive engineered nanomaterials (ENMs) with ultraviolet (UV) light triggers the formation of reactive intermediates, consequently altering the ecotoxicological potential of co-occurring organic micropollutants including pesticides due to catalytic degradation. Simultaneously, omnipresent natural organic matter (NOM) adsorbs onto ENM surfaces, altering the ENM surface properties. Also, NOM absorbs light, reducing the photo(cata)lytic transformation of pesticides. Interactions between these environmental factors impact 1) directly the ecotoxicity of photoactive ENMs, and 2) indirectly the degradation of pesticides. We assessed the impact of field-relevant UV radiation (up to 2.6 W UVA/m²), NOM (4 mg TOC/L), and photoactive ENM (nTiO, 50 µg/L) on the acute toxicity of 6 pesticides in Daphnia magna. We selected azoxystrobin, dimethoate, malathion, parathion, permethrin, and pirimicarb because of their varying photo- and hydrolytic stabilities. Increasing UVA alone partially reduced pesticide toxicity, seemingly due to enhanced degradation. Even at 50 µg/L, nano-sized titanium dioxide (nTiO) reduced but also increased pesticide toxicity (depending on the applied pesticide), which is attributable to 1) more efficient degradation and potentially 2) photocatalytically induced formation of toxic by-products. Natural organic matter 1) partially reduced pesticide toxicity, not evidently accompanied by enhanced pesticide degradation, but also 2) inhibited pesticide degradation, effectively increasing the pesticide toxicity. Predicting the ecotoxicological potential of pesticides based on their interaction with UV light or interaction with NOM was hardly possible, which was even more difficult in the presence of nTiO. Environ Toxicol Chem 2020;39:2237-2246. © 2020 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
Topics: Animals; Catalysis; Daphnia; Dimethoate; Malathion; Nanoparticles; Organic Chemicals; Pesticides; Titanium; Ultraviolet Rays; Water Pollutants, Chemical
PubMed: 33464613
DOI: 10.1002/etc.4851 -
Pest Management Science Apr 2021We investigated several aspects that could affect the role of the European earwig (Forficula auricularia) as a generalist predator in orchards: (i) seasonal activity in...
Forficula auricularia (Dermaptera) in orchards: Monitoring seasonal activity, the effect of pesticides, and the perception of European fruit growers on its role as a predator or pest.
BACKGROUND
We investigated several aspects that could affect the role of the European earwig (Forficula auricularia) as a generalist predator in orchards: (i) seasonal activity in apple orchards, (ii) effectiveness of two cardboard trap types (roll vs tape) to enhance earwig densities, (iii) the effect of pesticides (chlorpyrifos-methyl, spinosad, indoxacarb, spirotetramat, pirimicarb, sulphur, fluopyram tebuconazole) on earwig survival and behaviour, and (iv) the perception of European fruit growers of the earwigs' role as a predator or pest.
RESULTS
The highest activity of earwigs in apple trees was observed in summer. Roll traps were a more effective capture method than tape traps. The roll traps also significantly increased earwig abundances in trees. Only the earwigs exposed to the insecticides indoxacarb, spinosad and chlorpyrifos-methyl had significantly higher mortality and more erratic behaviour than earwigs from the control treatment. Earwigs from orchards with long-term (>10 years) application of chlorpyrifos-methyl had significantly lower mortality when exposed to this insecticide than earwigs from nonsprayed orchards. The fruit growers perceived earwigs as natural enemies of aphids and psyllids but also as pests. However, they regarded the damage caused by earwigs as economically unimportant without the necessity for management against them.
CONCLUSION
Fruit growers can increase earwig densities by installing rolled cardboard bands around trees. The highest seasonal activity of European earwigs coincides with applications of insecticides in orchards. This could disturb the earwigs' potential to suppress pest populations because several insecticides widely used in orchards have lethal and sublethal effects on earwigs even though they seem to develop some degree of pesticide resistance over time. © 2020 Society of Chemical Industry.
Topics: Animals; Auricularia; Fruit; Insecta; Insecticides; Malus; Perception; Pesticides; Seasons
PubMed: 33200877
DOI: 10.1002/ps.6189 -
Food Chemistry Nov 2019Matrix effects in complex tea matrices remains a great challenge to rapid quantitative analysis of multi-residue pesticides by analysis of mass spectrometry. Herein, a...
Matrix effects in complex tea matrices remains a great challenge to rapid quantitative analysis of multi-residue pesticides by analysis of mass spectrometry. Herein, a mixed-mode polymer cationic exchange based dispersive solid-phase extraction (DSPE) procedure was established to eliminate matrix effects of tea for a rapid target alkaline multi-residue pesticides analysis. One-step DSPE procedure can eliminate matrix interferences from the tea extract without additional dilution or tedious cleanup operations. Liquid chromatography-high resolution mass spectrometry using pre-column dilution injection mode was used as the detection technique, while eliminating solvent effects of target analytes and improving the detection sensitivity. Based on this effective analytical method, the results of absolute matrix effects were within 0.77-1.08 for quantitation of the 68 alkaline pesticides, and superior relative matrix effects were also achieved with RSD values below 9.8%. Finally, this method was validated and applied to the alkaline pesticides analysis of the 123 tea samples.
Topics: Caffeine; Chromatography, Liquid; Food Analysis; Food Contamination; Mass Spectrometry; Pesticide Residues; Polyphenols; Reproducibility of Results; Solid Phase Extraction; Tea
PubMed: 31302427
DOI: 10.1016/j.foodchem.2019.125146 -
Environmental Science and Pollution... May 2021Modern technologies (especially with the help of autonomous measurement and control systems) introduced automatic composters for the disposal of household food waste...
Modern technologies (especially with the help of autonomous measurement and control systems) introduced automatic composters for the disposal of household food waste production. Environmental risks connected with the utilization of these composts can be characterized by the high electrical conductivity caused by a presence of sodium chloride in food. Electrical conductivity influences the ecotoxicity of the composts. The presence of pesticides in composted food also represents an important environmental problem. The following pesticides were found in compost samples from household food waste: 1,3,5-triazine, methyl trithion, bifenthrin, bifenox, carbophenothion, pirimicarb, dioxacarb, desmetryn. Pesticide content in composts varied from 0.3 to 16.3 μg/kg, the average value being 30.4 ± 10.1 μg/kg dry matter. The higher decomposition was found of "modern" pesticides in the composters. The removal of salts can ensure that inhibition will be < 30% while washing with the ratio of 1:3 will result in the inhibition < 5%. However, this way of processing is not effective for other organisms-Poecilia reticulata (mortality 100%) and Daphnia magna (immobilisation 100%) using this procedure as well as washing of the compost in the ratio 3:1.
Topics: Composting; Food; Refuse Disposal; Soil
PubMed: 32705551
DOI: 10.1007/s11356-020-09916-5 -
Journal of Economic Entomology Jun 2024Aphids (Hemiptera: Aphidoidea) are economically important crop pests worldwide. Because of growing issues with insecticide resistance and environmental contamination by...
Aphids (Hemiptera: Aphidoidea) are economically important crop pests worldwide. Because of growing issues with insecticide resistance and environmental contamination by insecticides, alternate methods are being explored to provide aphid control. Aphids contain endosymbiotic bacteria that affect host fitness and could be targeted as potential biocontrol agents, but such novel strategies should not impact the effectiveness of traditional chemical control. In this work, we used a novel endosymbiont transinfection to examine the impact of the endosymbiont Rickettsiella viridis on chemical tolerance in 3 important agricultural pest species of aphid: Myzus persicae (Sulzer) (Hemiptera: Aphididae), Rhopalosiphum padi (Linnaeus) (Hemiptera: Aphididae), and Diuraphis noxia (Mordvilko ex Kurdjumov) (Hemiptera: Aphididae). We tested tolerance to the commonly used insecticides alpha-cypermethrin, bifenthrin, and pirimicarb using a leaf-dip bioassay. We found no observed effect of this novel endosymbiont transinfection on chemical tolerance, suggesting that the strain of Rickettsiella tested here could be used as a biocontrol agent without affecting sensitivity to insecticides. This may allow Rickettsiella transinfections to be used in combination with chemical applications for pest control. The impacts of other endosymbionts on insecticide tolerance should be considered, along with tests on multiple aphid clones with different inherent levels of chemical tolerance.
PubMed: 38935037
DOI: 10.1093/jee/toae136