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International Journal of Environmental... Dec 2022Organophosphates (OPPs) are an important element of modern agriculture; however, because they are being used excessively, their residues are leaching and accumulating in...
Organophosphates (OPPs) are an important element of modern agriculture; however, because they are being used excessively, their residues are leaching and accumulating in the soil and groundwater, contaminating aquatic and terrestrial food chains. An important OPP called disulfoton is frequently used to eradicate pests from a wide range of crops, including Brazil's coffee crops. Additionally, it does not easily degrade in the environment, and as such, this compound can slowly build up in living organisms such as humans. Moreover, this compound has been classified as "extremely hazardous" by the World Health Organization. This study evaluated the degradation efficiency of disulfoton using a Fenton-like reaction catalyzed by magnetite nanoparticles and determined the toxicity of the by-products of the degradation process using the bioindicator . Further, the removal efficiency of disulfoton was determined to be 94% under optimal conditions. On the other hand, the bioassay showed different toxic, cytotoxic, genotoxic, and mutagenic outcomes even after the remediation process. In conclusion, the Fenton process catalyzed by magnetite nanoparticles presents great efficiency for the oxidation of disulfoton. However, it is important to highlight that the high degradation efficiency of the Fenton-based process was not sufficient to achieve detoxification of the samples.
Topics: Humans; Disulfoton; Oxidation-Reduction; Agriculture; Soil; Crops, Agricultural
PubMed: 36613108
DOI: 10.3390/ijerph20010786 -
Environmental Science and Pollution... Dec 2023Pesticide deposits post-treatment and before diffusing inside the plants are exposed to sunlight. Many of them degrade into a variety of photoproducts that may be...
Pesticide deposits post-treatment and before diffusing inside the plants are exposed to sunlight. Many of them degrade into a variety of photoproducts that may be harmful to living beings through accidental ingestion. The addition of ultraviolet light absorbers to the pesticide formulations is an attractive strategy to prevent photodegradation of the pesticides. Water-soluble quaternary ammonium ultraviolet light absorbers (QAUVAs) were synthesized from 2,4-dihydroxy benzophenones (BP-1) and their structures were confirmed by H NMR, C NMR, UV, and FTIR. A cost-saving approach for the photoprotection of disulfoton insecticide using these QAUVAs is presented. All the four QAUVAs exhibit excellent UV screening effect. The insecticide disulfoton was recovered in much higher amounts (22.27 ~ 25.64% higher than control) when it was irradiated in the presence of QAUVAs in comparison with the amount of recovery of pesticide exposed in absence of them.
Topics: Photolysis; Disulfoton; Insecticides; Ultraviolet Rays; Pesticides; Benzophenones
PubMed: 35687284
DOI: 10.1007/s11356-022-21247-1 -
Se Pu = Chinese Journal of... Feb 2022Disulfoton, an organophosphorus pesticide, is used to control cotton, beet, potato, and other seedling period aphids, leaf moths, underground pests, etc., with internal...
[Determination of disulfoton and its metabolites in agricultural products by dispersive soild phase extraction-ultra high performance liquid chromatography-tandem mass spectrometry].
Disulfoton, an organophosphorus pesticide, is used to control cotton, beet, potato, and other seedling period aphids, leaf moths, underground pests, etc., with internal absorption, killing, gastric poisoning, and fumigation. Disulfoton is a highly toxic organophosphate pesticide, which can inhibit cholinesterase activity, resulting in neurophysiological disorders by inhalation, feeding, and transdermal absorption. Disulfoton is difficult to degrade in the environment, which leads to enrichment in organisms and interference with endocrine. This compound is harmful to the ecological environment and human health. To ensure the quality and safety of food, it is important to develop a detection method for disulfoton and its metabolites in agricultural products. A reliable method based on dispersive solid phase extraction (d-SPE) with ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was developed for the determination of disulfoton and its metabolites (disulfoton sulfone, disulfoton sulfoxide, demeton-, demeton- sulfone, and demeton- sulfoxide) in agricultural products (pea, asparagus, wheat, coffee bean, and peanut). The optimal extraction method was as follows: 5.0 g the samples were extracted with acetonitrile (wheat, coffee bean, and peanut presoaked in 5 mL water) in a 50 mL centrifuge tube, followed by 10 min vortex. Before 30 s vortex, 4 g NaCl was added. After 5 min centrifugation, 1.5 mL of the supernatant was cleaned up with 50 mg octadecylsilane bonded silica (C), 50 mg primary secondary amine (PSA), and 50 mg aminopropyl (NH) adsorbents. The analytes were separated on a Thermo Syncronis C column (150 mm×2.1 mm, 5 μm) with gradient elution using water and acetonitrile at a column temperature of 40 ℃. The injection volume was 2 μL. Disulfoton and its metabolites were analyzed in multiple reaction monitoring (MRM) mode with positive electrospray ionization (ESI) for the selective quantification. Qualitative and quantitative analyses were accorded to the retention times and characteristic ion pairs with one parent ion and two fragment ions. Quantitative analysis was performed by an external standard method using matrix-matched calibration curves. All the parameters that affected the extraction efficiencies were optimized. C, PSA, and NH gave good recoveries of 87.9%-109.0%. Other adsorbents, multiwalled carbon nanotubes (MWCNTs), hydroxylated multiwalled carbon nanotubes (OH-MWCNTs), carboxylated multiwalled carbon nanotubes (COOH-MWCNTs), octylsilane bonded silica (C), strong cation exchange (SCX) and neutral alumina (-AlO), led to recoveries below 56.2%. The combination of adsorbents was also considered. Seven different combinations of 50 mg C, 50 mg PSA, and 50 mg NH were chosen for the optimization experiments. There were no obvious differences in these combinations, and the target analytes recoveries ranged from 81.0% to 109.3% with relative standard deviations (RSDs) between 0.6% and 12.5%. The matrix effect could affect the extraction efficiency. The adsorbents of 50 mg C, 50 mg PSA, and 50 mg NH showed weaker matrix effects as compared with other combinations of adsorbents in the instrument. The results for the matrix effect showed that peanuts and asparagus exceeded 20%, requiring matrix-matched calibration curves. Under the optimized conditions, disulfoton and its metabolites showed good linearities (≥0.9981) in the range of 2.0-200.0 μg/L. The average spiked recoveries of disulfoton and its metabolites in peas, asparagus, wheat, peanuts, and coffee beans ranged from 75.0% to 110.0%, with RSDs of 0.7% to 14.9%. The limits of detection (LODs) were between 0.02 and 2.0 μg/kg, and the limits of quantification (LOQs) were 5.0 μg/kg. The method was applied for the detection of 80 commercial productions, and neither disulfoton nor its metabolites were found. The proposed method is rapid, accurate, highly selective, and sensitive, and it is suitable for the simultaneous determination of disulfoton and its metabolites in grain, oil crops, vegetables, and other matrices.
Topics: Chromatography, High Pressure Liquid; Disulfoton; Humans; Nanotubes, Carbon; Organophosphorus Compounds; Pesticides; Solid Phase Extraction; Tandem Mass Spectrometry
PubMed: 35080159
DOI: 10.3724/SP.J.1123.2021.04028 -
Analytica Chimica Acta Mar 2020Magnetic restricted-access carbon nanotubes (M-RACNTs) were synthesised and used for dispersive solid phase extraction of organophosphates (chlorpyriphos, malathion,...
Magnetic restricted-access carbon nanotubes (M-RACNTs) were synthesised and used for dispersive solid phase extraction of organophosphates (chlorpyriphos, malathion, disulfoton, pirimiphos) from commercial bovine raw milk samples. Due to their magnetic susceptibility, M-RACNTs were easily separated from the samples/solvents using a neodymium magnet, and the extracted organophosphates were analysed by gas chromatography-mass spectrometry. The protein exclusion capacity was about 100%. Kinetic and isotherm data (for M-RACNTs - malathion interaction) were adequately adjusted to the pseudo-second order and Sips models, respectively, and the maximum adsorption capacity was about 0.55 mg g. The method presented linear ranges from 5.0 to 40.0 μg L for all analytes, with determination coefficients from 0.9902 to 0.9963. The intra-assay precisions (as relative standard deviation) and accuracies (as relative error) ranged from 10.47 to 19.85% and from -0.18 to -18.80%, respectively, whereas the inter-assay precisions ranged from 6.48 to 18.76% and from -0.22 to 19.49%, respectively for 5.0, 20.0 and 40.0 μg L organophosphates levels. The organophosphates were not stable at 4 and 24 h (relative errors ranged from -39.30 to 72.07% and -69.64 to 75.95%, respectively). Limits of detection ranged from 0.36 to 0.95 μg L, and 5 μg L was defined as the limit of quantification for all the analytes. The proposed method was applied in the determination of organophosphates in five commercial milk samples, and no pesticides were detected.
Topics: Adsorption; Animals; Food Contamination; Gas Chromatography-Mass Spectrometry; Limit of Detection; Magnetic Phenomena; Milk; Nanotubes, Carbon; Organophosphates; Pesticides; Reproducibility of Results; Solid Phase Extraction
PubMed: 32043990
DOI: 10.1016/j.aca.2019.12.039 -
Food Chemistry Nov 2019An analytical method involving QuEChERS (quick, easy, cheap, effective, rugged, and safe) sample preparation, followed by LC-MS/MS and GC-MS/MS was developed and...
An analytical method involving QuEChERS (quick, easy, cheap, effective, rugged, and safe) sample preparation, followed by LC-MS/MS and GC-MS/MS was developed and validated for the determination of 60 pesticides in eggs. Recoveries of 70-120% were achieved for selected pesticides and relative standard deviations <20% were obtained for most analytes at three concentrations. The limit of quantification was <10 µg kg for 83% of the total pesticides. This method was used to analyze 58 egg samples and the residues of seven pesticides (disulfoton, fipronil sulfone, cyromazine, o,p-DDT, p,p-DDD, p,p-DDT, and permethrin) were quantified in 16 egg samples at levels of 5-10 µg kg, which was below the corresponding the maximum residue levels, as established by Korean Ministry of Food and Drug Safety. We demonstrated that LC-MS/MS and GC-MS/MS in combination with QuEChERS can be used to routinely monitor multiple pesticide residues in egg samples.
Topics: Animals; Chickens; Chromatography, High Pressure Liquid; Disulfoton; Eggs; Female; Gas Chromatography-Mass Spectrometry; Limit of Detection; Pesticide Residues; Pyrazoles; Reproducibility of Results; Tandem Mass Spectrometry
PubMed: 31260955
DOI: 10.1016/j.foodchem.2019.125050 -
PloS One 2019Senescence Marker Protein (SMP30) is a metalloenzyme that shows lactonase activity in the ascorbic acid (AA) biosynthesis pathway in non-primate mammals such as a mouse....
Senescence Marker Protein (SMP30) is a metalloenzyme that shows lactonase activity in the ascorbic acid (AA) biosynthesis pathway in non-primate mammals such as a mouse. However, AA biosynthesis does not occur in the primates including humans. Several studies have shown the role of SMP30 in maintaining calcium homeostasis in mammals. In addition, it is also reported to have promiscuous enzyme activity with an organophosphate (OP) substrate. Hence, this study aims to recombinantly express and purify the SMP30 proteins from both mouse and human, and to study their structural alterations and functional deviations in the presence of different divalent metals. For this, mouse SMP30 (MoSMP30) as well as human SMP30 (HuSMP30) were cloned in the bacterial expression vector. Proteins were overexpressed and purified from soluble fractions as well as from inclusion bodies as these proteins were expressed largely in insoluble fractions. The purified proteins were used to study the folding conformations in the presence of different divalent cations (Ca2+, Co2+, Mg2+, and Zn2+) with the help of circular dichroism (CD) spectroscopy. It was observed that both MoSMP30 and HuSMP30 acquired native folding conformations. To study the metal-binding affinity, dissociation constant (Kd values) were calculated from UV-VIS titration curve, which showed the highest affinity of MoSMP30 with Zn2+. However, HuSMP30 showed the highest affinity with Ca2+, suggesting the importance of HuSMP30 in maintaining calcium homeostasis. Enzyme kinetics were performed with γ-Thiobutyrolactone and Demeton-S in the presence of different divalent cations. Interestingly, both the proteins showed lactonase activity in the presence of Ca2+. In addition, MoSMP30 and HuSMP30 also showed lactonase activity in the presence of Co2+ and Zn2+ respectively. Moreover, both the proteins showed OP hydrolase activities in the presence of Ca2+ as well as Zn2+, suggesting the metal-dependent promiscuous nature of SMP30.
Topics: 4-Butyrolactone; Animals; Binding Sites; Calcium-Binding Proteins; Cations, Divalent; Disulfoton; Humans; Intracellular Signaling Peptides and Proteins; Kinetics; Mice; Mice, Inbred BALB C; Molecular Dynamics Simulation; Protein Binding; Sequence Homology, Amino Acid
PubMed: 31220150
DOI: 10.1371/journal.pone.0218629 -
Royal Society Open Science Jul 2018This study was performed to determine the storage stability of organophosphorus pesticide residues in high oil content commodity matrices, peanut and soya bean. The...
This study was performed to determine the storage stability of organophosphorus pesticide residues in high oil content commodity matrices, peanut and soya bean. The storage conditions included different types of solvents (ethyl acetate, acetone and hexane) and corresponding extracted matrix solutions, light and temperature. It was found that three pesticides degraded quickly especially in ethyl acetate solvent. They decreased greater than 30% when stored for 3 days at -20°C in ethyl acetate; the results showed that the stability could be improved in the extracted matrix solutions. Light had a slight effect for stability of phorate and fenthion, while it played an important effect for disulfoton with the exception of ethyl acetate as solvent. Even at -20°C, exposure to solvents or extracted matrix solution resulted in 40.67, 96.33 and 35.07% loss of phorate, disulfoton and fenthion. Hence, it could be assumed that these three residues could be more stable at lower temperature, in the dark and in acetone or hexane extracted peanut and soya bean solutions.
PubMed: 30109115
DOI: 10.1098/rsos.180757 -
Macromolecular Rapid Communications Jun 2018The threat of chemical warfare agents (CWA) compels research into novel self-decontaminating materials (SDM) for the continued safety of first-responders, civilians, and...
The threat of chemical warfare agents (CWA) compels research into novel self-decontaminating materials (SDM) for the continued safety of first-responders, civilians, and active service personnel. The capacity to actively detoxify, as opposed to merely sequester, offending agents under typical environmental conditions defines the added value of SDMs in comparison to traditional adsorptive materials. Porous polymers, synthesized via the high internal phase emulsion (HIPE) templating, provide a facile fabrication method for materials with permeable open cellular structures that may serve in air filtration applications. PolyHIPEs comprising polydicyclopentadiene (polyDCPD) networks form stable hydroperoxide species following activation in air under ambient conditions. The hydroperoxide-containing polyDCPD materials react quickly with CWA simulants, Demeton-S and 2-chloroethyl ethyl sulfide, forming oxidation products as confirmed via gas chromatography mass spectrometry. The simplicity of the detoxification chemistry paired with the porous foam form factor presents an exciting opportunity for the development of self-decontaminating filter media.
Topics: Chemical Warfare Agents; Chromatography, Liquid; Decontamination; Disulfoton; Emulsions; Hydrogen Peroxide; Indenes; Mass Spectrometry; Mustard Gas; Oxidation-Reduction; Polymers; Porosity; Styrenes; Time Factors
PubMed: 29786164
DOI: 10.1002/marc.201800194 -
Ecotoxicology and Environmental Safety Jul 2018The use of multiple biomarkers has been shown to be an efficient method for evaluating environmental contamination. In this work, we evaluate neurotoxic effects and the...
The use of multiple biomarkers has been shown to be an efficient method for evaluating environmental contamination. In this work, we evaluate neurotoxic effects and the antioxidant system responses of the R. branneri collected in two streams of lower Iguazu River basin, relating them with different percentage of vegetation coverture, presence of pesticides and fall and winter seasons. The biological samples were collected in March and August of 2015, from two streams that belong to the lower Iguazu River basin (Brazil): the Manoel Gomes River and the Arquimedes Stream. Soil analyses were performed, and the results showed the presence of the following organophosphates in the Manoel Gomes River and the Arquimedes Stream: disulfoton, methyl parathion, and ronnel. The present study detected inhibition of cholinesterase activity in the brain and muscle of fish samples during the fall from the Manoel Gomes River and the Arquimedes Stream. In the Manoel Gomes River, elevated lipoperoxidation was also observed during the fall. It was observed that the increase or decrease of biomarkers was related to temporal variation and, possibly, to the exposure of animals to agrochemicals. Although the Manoel Gomes River and the Arquimedes Stream are located in regions with large areas of vegetation, the soil analyses show that agrochemical residues are able to reach these locations, which suggests that the fauna are in contact with oxidant and anti-cholinesterase agents during the fall, in addition to respond differently during each season.
Topics: Animals; Biomarkers; Brain; Brazil; Catfishes; Cholinesterase Inhibitors; Cholinesterases; Environmental Monitoring; Muscles; Organophosphates; Pesticides; Rivers; Seasons; Water Pollutants, Chemical
PubMed: 29522881
DOI: 10.1016/j.ecoenv.2018.02.063