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The quality and safety of edible vegetable oils are closely related to human life and health, meaning it is of great significance to explore the rapid detection methods of pesticide residues in edible vegetable oils. This study explored the applicability potential of substrate-assisted laser-induced breakdown spectroscopy (LIBS) for quantitatively determining fenthion in soybean oils. First, we explored the impact of laser energy, delay time, and average oil film thickness on the spectral signals to identify the best experimental parameters. Afterward, we quantitatively analyzed soybean oil samples using these optimized conditions and developed a full-spectrum extreme learning machine (ELM) model. The model achieved a prediction correlation coefficient (RP2) of 0.8417, a root mean square error of prediction (RMSEP) of 167.2986, and a mean absolute percentage error of prediction (MAPEP) of 26.46%. In order to enhance the prediction performance of the model, a modeling method using the Boruta algorithm combined with the ELM was proposed. The Boruta algorithm was employed to identify the feature variables that exhibit a strong correlation with the fenthion content. These selected variables were utilized as inputs for the ELM model, with the RP2, RMSEP, and MAPEP of Boruta-ELM being 0.9631, 71.4423, and 10.06%, respectively. Then, the genetic algorithm (GA) was used to optimize the parameters of the Boruta-ELM model, with the RP2, RMSEP, and MAPEP of GA-Boruta-ELM being 0.9962, 11.005, and 1.66%, respectively. The findings demonstrate that the GA-Boruta-ELM model exhibits excellent prediction capability and effectively predicts the fenthion contents in soybean oil samples. It will be valuable for the LIBS quantitative detection and analysis of pesticide residues in edible vegetable oils. [ABSTRACT FROM AUTHOR]

• Heterogeneous kinetics of fenthion and parathion toward OH radicals was studied. • OH radicals play an important role in their atmospheric degradation. • A negative RH and a positive temperature dependences of kinetics were observed. • Heterogeneous rate constants and atmospheric lifetimes were obtained. Fenthion and parathion are two representative kinds of organophosphorus pesticides and widely used in agriculture. They are directly or indirectly released into the atmosphere by spraying or volatilization processes. However, their heterogeneous reactivity toward OH radicals has not yet been well understood. Therefore, this work investigated the heterogeneous kinetics of the OH-initiated degradation of surface-bound fenthion and parathion using a flow reactor. The results showed that OH radicals played an important role in the atmospheric degradation of fenthion and parathion. Their average rate constants were (7.20 ± 0.77) × 10−12 and (10.40 ± 0.60) × 10−12 cm3/(mol· sec) at a relative humidity (RH) and temperature of 35% and 20 °C, respectively, suggesting that they have relatively short lifetimes in the atmosphere. In addition, a negative RH dependence and a positive temperature dependence of the rate constants were observed. The Arrhenius expressions of fenthion and parathion were k 2 = (1.34 ± 0.48) × 10−9exp[−(1432.59 ± 105.29)/T] and k 2 = (1.96 ± 1.38) × 10−9exp[−(1619.98 ± 222.02)/T], respectively, and their overall activation energy was estimated to be (11.88 ± 0.87) and (13.48 ± 1.83) kJ/mol. The experimental results will update the kinetic data of fenthion and parathion in the atmosphere and be helpful to further understand their atmospheric transportation processes. [Display omitted] [ABSTRACT FROM AUTHOR]

The quality and safety of edible vegetable oils are closely related to human life and health, meaning it is of great significance to explore the rapid detection methods of pesticide residues in edible vegetable oils. This study explored the applicability potential of substrate-assisted laser-induced breakdown spectroscopy (LIBS) for quantitatively determining fenthion in soybean oils. First, we explored the impact of laser energy, delay time, and average oil film thickness on the spectral signals to identify the best experimental parameters. Afterward, we quantitatively analyzed soybean oil samples using these optimized conditions and developed a full-spectrum extreme learning machine (ELM) model. The model achieved a prediction correlation coefficient (RP2) of 0.8417, a root mean square error of prediction (RMSEP) of 167.2986, and a mean absolute percentage error of prediction (MAPEP) of 26.46%. In order to enhance the prediction performance of the model, a modeling method using the Boruta algorithm combined with the ELM was proposed. The Boruta algorithm was employed to identify the feature variables that exhibit a strong correlation with the fenthion content. These selected variables were utilized as inputs for the ELM model, with the RP2, RMSEP, and MAPEP of Boruta-ELM being 0.9631, 71.4423, and 10.06%, respectively. Then, the genetic algorithm (GA) was used to optimize the parameters of the Boruta-ELM model, with the RP2, RMSEP, and MAPEP of GA-Boruta-ELM being 0.9962, 11.005, and 1.66%, respectively. The findings demonstrate that the GA-Boruta-ELM model exhibits excellent prediction capability and effectively predicts the fenthion contents in soybean oil samples. It will be valuable for the LIBS quantitative detection and analysis of pesticide residues in edible vegetable oils.

In the present work, composites with non-toxic metal oxides, such as TiO2 and ZnO, and a natural red clay (taua) reach in hematite were used in the photocatalytic degradation of Fenthion. The composite TiO2/Taua (0.5:1 wt. ratio) and pure TiO2 were prepared by sol-gel method while ZnO/Taua (0.5:1 wt. ratio) and pure ZnO were prepared by Pechini method. The materials were characterized by XRD, SEM, EDX, and DRS. The anatase phase was formed in both pure TiO2 and TiO2/Taua, while the hexagonal phase was formed in pure ZnO and ZnO/Taua. The bandgap energies for the two composites were narrowed compared to the respective pure oxides as consequence of the hematite (α-Fe2O3, Eg = 2.1 eV) in the red clay, reaching 2.1 eV for TiO2/Taua and 2.0 eV for ZnO/Taua, while the bandgap energies for pure TiO2 and ZnO were 3.2 and 3.0 eV, respectively. Fenthion was not degraded in the dark, but the concentration droped 20% after 180 min under visible light irradiation without photocatalyst and 60% after 210 min in the presence of the pure red clay. Both TiO2/Taua and ZnO/Taua composites were also photocatalytic active to degrade Fenthion (λ > 420 nm), with degradation of 78% (in 180 min) and 85% (in 210 min) respectively. In the optimized conditions (pH 2, 100 mg L−1 of H2O2 and 30 mg L−1 of Fenthion), the ZnO/Taua composite was the most efficient, reaching 89% degradation in up to 30 min, with Fenthion sulfoxide as the degradation product. [ABSTRACT FROM AUTHOR]

In the present study, a molecularly imprinted solid-phase extraction (MISPE) technique coupled with high-performance liquid chromatography was applied for selective extraction and recognition of fenthion insecticide in the biological sample. The nanoparticles of fenthion imprinted polymer were prepared by precipitation polymerisation using methacrylic acid (MAA) as functional monomer, ethylene glycol dimethacrylate (EGDMA) as cross-linker, and 70 mL of chloroform. Morphological and structural characterisation was achieved by scanning electron microscopy and infrared spectrometry. The optimisation of parameters being effective on extraction yield was carried out by employing the central composite design (CCD). The empirical models were developed to link the output response and input variables and the proposed models were tested for significance through analysis of variance (ANOVA). The optimum conditions leading to the maximum efficiency of MISPE were sorbent mass of 8.61 mg, sample pH 4.93, sample flow rate of 2.07 mLmin−1, as well as 1.94 mL of methanol/acetic acid (95.7:4.3, v/v) at the flow rate of 1 mLmin−1 as elution solvent. Under the optimised conditions, a linear range of 20–120 μgL−1 was obtained and the limit of detection was found to be 4.58 μgL−1. Analysis of spiked urine samples demonstrated the satisfactory efficiency of the designed protocol ranging from 92.69 to 95.64% and the relative standard deviation (RSD) was calculated to be lower than 3.75%. [ABSTRACT FROM AUTHOR]

Modern agricultural production is greatly dependent on pesticide usage, which results in severe environmental pollution, health risks and degraded food quality and safety. Molecularly imprinted polymers are one of the most prominent approaches for the detection of pesticide residues in food and environmental samples. In this research, we prepared molecularly imprinted polymers for fenthion detection by using beta-cyclodextrin as a functional monomer and a room-temperature ionic liquid as a cosolvent. The characterization of the developed polymers was carried out. The polymers synthesized by using the room-temperature ionic liquid as the cosolvent had a good adsorption efficiency of 26.85 mg g−1, with a short adsorption equilibrium time of 20 min, and the results fitted well with the Langmuir isotherm model and pseudo-second-order kinetic model. The polymer showed cross-selectivity for methyl-parathion, but it had a higher selectivity as compared to acetamiprid and abamectin. A recovery of 87.44–101.25% with a limit of detection of 0.04 mg L−1 and a relative standard deviation of below 3% was achieved from soil, lettuce and grape samples, within the linear range of 0.02–3.0 mg L−1, using high-performance liquid chromatography with an ultraviolet detector. Based on the results, we propose a new, convenient and practical analytical method for fenthion detection in real samples using improved imprinted polymers with room-temperature ionic liquid. [ABSTRACT FROM AUTHOR]

Modern agricultural production is greatly dependent on pesticide usage, which results in severe environmental pollution, health risks and degraded food quality and safety. Molecularly imprinted polymers are one of the most prominent approaches for the detection of pesticide residues in food and environmental samples. In this research, we prepared molecularly imprinted polymers for fenthion detection by using beta-cyclodextrin as a functional monomer and a room-temperature ionic liquid as a cosolvent. The characterization of the developed polymers was carried out. The polymers synthesized by using the room-temperature ionic liquid as the cosolvent had a good adsorption efficiency of 26.85 mg g−1, with a short adsorption equilibrium time of 20 min, and the results fitted well with the Langmuir isotherm model and pseudo-second-order kinetic model. The polymer showed cross-selectivity for methyl-parathion, but it had a higher selectivity as compared to acetamiprid and abamectin. A recovery of 87.44–101.25% with a limit of detection of 0.04 mg L−1 and a relative standard deviation of below 3% was achieved from soil, lettuce and grape samples, within the linear range of 0.02–3.0 mg L−1, using high-performance liquid chromatography with an ultraviolet detector. Based on the results, we propose a new, convenient and practical analytical method for fenthion detection in real samples using improved imprinted polymers with room-temperature ionic liquid.

In this paper, a green proline choline ionic liquid ([Ch][Pro])-modified magnetic graphene oxide was used as the solid-phase extractant (Fe3O4@SiO2@GO@[Ch][Pro]), which was characterized by FIR and hysteresis loops. A novel method for the determination of fenthion by magnetic solid-phase extraction with HPLC was established. Factors affecting extraction and elution performance were investigated, such as the amount of extractant, pH of the solution, the time and temperature of extraction and elution. Under the best conditions, a good linearity (R2 = 0.9987) equation was obtained with the concentration range 0.02–10 μg mL−1. This method has been successfully applied to the determination of fenthion in apple samples and water samples. [ABSTRACT FROM AUTHOR]

Purpose: Today, the long-term effects of partial exposure of cholinesterase on the kidney continue to be a research topic. In this study, we aimed to histopathologically investigate the possible effect of acute toxicity due to fenthion, an organophosphate (OP) compound, on the kidneys. Methods: In all, 21 rats were randomly divided into three groups. Experimental group was each administered intraperitoneal 0.8 g/kg fenthion within physiologic serum. Sham group was only administered intraperitoneal physiologic serum. The control group continued normal nutrition with no procedure performed. After 24 h, all rats were sacrificed by cervical dislocation. Half of the recipient kidney tissues were examined histopathologically and the other half biochemically. Results: No histopathological findings were found in the control group. Rats in the experimental group were observed to have epithelial cell disorganization in tubules, moderate epithelial cell loss, and degeneration. Again, expansion of tubules, vacuolization of tubular epithelial cells, and tubular structure approaching atrophy were observed, with cells approaching apoptosis and common hemorrhage noted although rats in the sham group were observed to have mild tubular degeneration. Conclusions: It should not be forgotten that one of the causes of systemic complaints linked to acute toxicity exposed to the OP compound of fenthion may be cellular injury to glomerular and tubular structures in the kidneys.

In this work a direct, simple, fast and sensitive method to determine Fenthion was developed using a Boron-Doped Diamond Electrode and Square Wave Voltammetry. The method was applied into Passiflora alata herbal medicinal tinctures derivate from passion fruits. None previous treatment such as derivation or pre-concentration of the analyte was done. Cyclic Voltammetry results showed well defined irreversible oxidation peaks at around 1.27 V into the pH range of 2.0 to 8.0. Square Wave Voltammetry was used to analytical determination and the analysis parameters, such as frequency, amplitude and pH from support electrolyte were optimized. A calibration curve was obtained, and it was observed a sensitivity of 0.38 A/mol L-1 and linearity of 0.995. The limits of detection and quantification were 8.0x10-8 mol L-1 (21 mg L-1) and 2.5x10-7 mol L-1 (70 mg L-1), respectively. Recovery studies were applied using Passiflora alata samples fortified with Fenthion in concentrations of 2.5 µmol L-1and 4.0 µmol L-1, followed by the standard addition of the pesticide aliquots. It was observed that the complex matrix does not interferes in the method. The recovery results were about 98.4 and 112.0%, reinforcing that the method is suitable to determine the analyte in target complexes samples, such as Herbal Medicinal Plants. DOI: http://dx.doi.org/10.17807/orbital.v10i2.1077

The aim of this study was to reveal the effects of piperonyl butoxide which is a pesticide synergist agent, modulator of cytochrome P450, on oxidative and apoptotic responses of fenthion, an organophosphate pesticide in the liver of Oreochromis niloticus selected as a model organism. For this purpose, 0.567 mg/L fenthion (1/4 of LC50 value) and PBO concentration of 0.5 mg/L were applied for 24, 96 hours and 15 days. GPx, GR, GST and caspase enzyme activities; tGSH, GSH, GSSG, TBARS and HSP70 levels were analyzed in the liver. The results show that PBO induced hepatotoxic effects of fenthion by altering stress proteins, lipid peroxidation and GSH metabolism in the liver of O. niloticus. Liver cells could not be protected by GSH-related antioxidant system from oxidative damage of these agents. Furthermore, the results also show that fenthion may have caused induction in apoptosis, and PBO might have increased this effect of fenthion by affecting caspase-3 enzyme activity depending on oxidative stress in the liver samples obtained from O. niloticus. We conclude that these types of synergistic agents may increase toxic effects of other pesticides including OP fenthion and may also cause concerns for human and animal health as well as ecotoxicological effects. [ABSTRACT FROM AUTHOR]

• Details of the distribution of fenthion and its metabolites within the bodies of fenthion poisoning victims are unclear. • We developed and validated an LC/ESI–MS/MS method for the quantification of fenthion and its five metabolites in cadaveric body fluids. • We detected for the first time fenthion and all five fenthion metabolites in the cadaveric blood and CSF. • The concentrations of the oxidized forms of fenthion, including fenthion-sulfone and fenthion-sulfoxide, were higher in CSF than in the blood. Fenthion (MPP) is a popular organophosphorus pesticide that acts via inhibition of the enzyme cholinesterase. It is well known that fenthion is metabolized by plants, animals and soil microorganisms to sulfone and sulfoxide by oxidation of thioether and is further metabolized by conversion of P = S to P = O (oxon). Although human fenthion poisonings sometimes occur, details of the distribution of fenthion and its metabolites within the bodies of victims are unclear. In this study, we developed and validated an approach that uses liquid chromatography coupled with electrospray ionization−tandem mass spectrometry to quantify the concentrations of fenthion and its five metabolites (MPP-sulfoxide, MPP-sulfone, MPP-oxon, MPP-oxon sulfoxide and MPP-oxon sulfone) in the fluids [blood, cerebral spinal fluid (CSF) and urine] of a human cadaver. The calibration curves were linear in the concentration range 5–200 ng/mL. Our method allowed for repeatable and accurate quantification with intra- and inter-assay coefficients of variation smaller than 8.6% and 11.0%, respectively, for each target compound. We used the developed method to measure the fenthion concentration in the blood of a dead victim of fenthion poisoning and found the concentration to be in the comatose–fatal range. In addition, we detected for the first time fenthion and all five fenthion metabolites in the cadaveric blood and CSF. The concentrations of the oxidized forms of fenthion, including MPP-sulfone and MPP-sulfoxide, were higher in CSF than in the blood. [ABSTRACT FROM AUTHOR]

Background: A green sample preparation method named deep eutectic solvent-based single drop microextraction (DES-SDME) was developed and optimized for determining trace metribuzin, dichlorvos, and fenthion., Methods: Two hundred seventy experimental runs were performed, and the optimal values of the five influential factors in the DES-SDME method were determined. The design of the study was based on one factor at a time and the peak area of high-performance liquid chromatography was used as a benchmark for comparing analysis results., Results: After optimizing the effective factors, the linearity range, detection limit and quantification limit of the method were determined by drawing calibration curves for the studied analytes., Conclusion: The results indicated the success of the developed method in obtaining acceptable figures of merit as a green preparation method with accuracy and precision., (Copyright© 2023 Pourhossein et al. Published by Tehran University of Medical Sciences.)

Abstract The red-billed quelea (Quelea quelea) is the most important avian pest of small grain crops in semi-arid zones of Africa. Fenthion, an organophosphate, is the main avicide used for controlling the pest but it is highly toxic to non-target organisms. The only readily available pesticide that could replace fenthion is cyanophos, but this chemical is also highly toxic to non-target organisms, although less so than fenthion, and may be more expensive; however, more research on its environmental impacts is needed. Apart from chemical avicides, the only rapid technique to reduce the numbers of quelea substantially is the use of explosives combined with fuel to create fire-bombs but these also have negative effects on the environment, can be dangerous and have associated security issues. The technique is labour intensive and in practice can only be deployed against small (<5 ha) colonies and roosts. An integrated pest management (IPM) approach is the most environmentally benign strategy but, apart from when circumstances permit cultural control measures, most IPM activities only have realistic chances of succeeding in controlling quelea in small (<10 ha) areas. For instance, mass-trapping, which also has the advantage of providing a food source, is suitable when quelea roosts and colonies are less than 5 and 10 hectares in area, respectively. Nevertheless with both traps and mist nets, care is needed to minimise non-target casualties. Other IPM measures are also reviewed and the advantages and disadvantages of different methods tabulated. A related figure provides a decision tree for choosing appropriate measures for different circumstances. If fenthion has to be used, means of minimising its use include ensuring that spraying is only conducted when crops are threatened and that the lowest dosages necessary are applied. Regular training of pest control workers in how to use equipment correctly and in what to do in the case of accidental contamination of operators, and training of farmers on IPM principles and quelea biology through farmer field schools are recommended. Graphical abstract Image 1 Highlights • Alternatives to the organophosphate fenthion to control quelea birds that minimise environmental damage are reviewed, including trapping techniques, harvesting birds for food, cultural control techniques and bird-scaring methods. • Cyanophos, another organophosphate, and use of explosives both have severe environmental consequences. • Procedures to minimise environmental damage when fenthion is used are recommended. [ABSTRACT FROM AUTHOR]

Abstract Following the loss of two key pesticides, dimethoate and fenthion, producers and regulators need to develop new fruit fly management options. A systems approach is a likely measure in the post dimethoate and fenthion era. The risk of fruit fly can be mitigated at the regional, district and farm level. Some measures such as awareness and exclusion are common across all three levels. Pest control measures will be based on an understanding of climate, biology and pesticides. In this present paper, 28 different risk mitigation options that can be used in a systems approach in Australia are discussed. Highlights • Fruit fly management continues to change due to climate change and reduction in available pesticides. • Systems approach is an international phytosanitary standard for fruit fly management. • There are 28 risk management options in an Australian fruit fly systems approach to minimise the risk posed by fruit fly. • Systems approach can be used at a local, district or regional level and deploy different options. • Managers can mix and match options according to their circumstances. [ABSTRACT FROM AUTHOR]

Abstract Pollution has been less investigated in marine and coastal environments than in inland waters. The low levels at which pollutants are expected to be present in seawater calls for the use of reliable and high sensitivity analytical methodologies. In this context, this work presents the optimization and validation of an analytical method to determine 26 medium to highly polar pesticides in seawater based on solid phase extraction and liquid chromatography-tandem mass spectrometry detection. The developed methodology was linear, accurate (relative recoveries within 80–120% for most analytes), repeatable (relative standard deviations <18% for most analytes), and sensitive (limits of determination <1 ng/L for 89% of the compounds). The use of isotopically labeled compounds as surrogate standards compensated for low analyte recoveries and matrix effects. The method was applied to the analysis of seawater samples collected along the coastline of Catalonia (NE Spain). Overall, total pesticide loads were higher inside the marinas than outside. The booster biocides diuron and irgarol used in antifouling paintings and different triazine pesticides were the most abundant compounds. Irgarol was present above the maximum allowable concentration set in European regulations in 70% of the samples collected inside the marinas. A different pesticide pollution pattern, with MCPA and bentazone presenting the highest concentrations, was observed at the Ebro Delta area due to the impact of the agricultural activities carried out there. To the authors' knowledge, 4 out of the 26 target pesticides, namely, chlorfenvinphos, fenthion oxon, fenthion sulfone, and fenthion sulfoxide, have not been previously investigated in seawater. Graphical abstract Image 1 Highlights • Reliable and sensitive method optimized for analysis of 26 pesticides in seawater. • Reliability of results ensured by quantification with an isotope dilution approach. • Pesticide occurrence was evaluated in coastal and offshore water of Catalonia. • Total levels were higher inside the marinas than outside. • Irgarol, diuron and triazine pesticides were the most abundant compounds. [ABSTRACT FROM AUTHOR]

In this study, the potential of different sublethal concentrations (2.00, 4.00, 6.00, 8.00, 10.00, 20.00, 50.00, and 100.00 κg/100 g diet) of fenthion, an organophosphorus insecticide, to create oxidative stress and their effect on the antioxidant enzymes and lipid peroxidation of the larvae of the model organism Galleria mellonella were investigated. The activities of catalase (CAT) and superoxide dismutase (SOD) and the contents of malondialdehyde (MDA) and protein were determined using spectrophotometric methods. Fenthion caused a reduction in protein contents but an increase in the MDA content and CAT activity. Lower fenthion doses resulted in an increase in SOD activity, whereas higher fenthion doses significantly decreased SOD activity. Thus, the toxicity of fenthion due to oxidation was determined to result from the oxidative stress caused by the effect on activities of antioxidant enzymes such as CAT and SOD. [ABSTRACT FROM AUTHOR]

Purpose: Today, the long-term effects of partial exposure of cholinesterase on the kidney continue to be a research topic. In this study, we aimed to histopathologically investigate the possible effect of acute toxicity due to fenthion, an organophosphate (OP) compound, on the kidneys. Methods: In all, 21 rats were randomly divided into three groups. Experimental group was each administered intraperitoneal 0.8 g/kg fenthion within physiologic serum. Sham group was only administered intraperitoneal physiologic serum. The control group continued normal nutrition with no procedure performed. After 24 h, all rats were sacrificed by cervical dislocation. Half of the recipient kidney tissues were examined histopathologically and the other half biochemically. Results: No histopathological findings were found in the control group. Rats in the experimental group were observed to have epithelial cell disorganization in tubules, moderate epithelial cell loss, and degeneration. Again, expansion of tubules, vacuolization of tubular epithelial cells, and tubular structure approaching atrophy were observed, with cells approaching apoptosis and common hemorrhage noted although rats in the sham group were observed to have mild tubular degeneration. Conclusions: It should not be forgotten that one of the causes of systemic complaints linked to acute toxicity exposed to the OP compound of fenthion may be cellular injury to glomerular and tubular structures in the kidneys. [ABSTRACT FROM AUTHOR]

A simultaneous analytical method for the organophosphorus insecticide fenthion and its five metabolites (fenthion oxon, fenthion oxon sulfoxide, fenthion oxon sulfone, fenthion sulfoxide, and fenthion sulfone) was developed based on ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Five matrices (brown rice, chili pepper, orange, potato, and soybean) were selected to validate the method. The target compounds were analyzed using positive electrospray ionization in the multiple reaction monitoring mode. For the best sensitivity in regard to the detector response, water and methanol containing formic acid (0.1%) were selected as the mobile phase. The optimum extraction efficiency was obtained through a citrate-buffered QuEChERS (quick, easy, cheap, effective, rugged, and safe) method. Recovery tests were carried out at three spiking levels (n = 3). At all fortification levels, the accuracy and precision results were between 70% and 120% with a relative standard deviation of ≤15%. The limit of quantitation was 0.01 mg/kg, and the correlation coefficients (r2) of the matrix-matched calibration curves were >0.99. Significant signal suppression in the detector responses were observed for all matrices, suggesting that a compensation method, such as matrix-matched calibration, is required to provide accurate quantitative results. The applicability of the presented method was confirmed for the simultaneous analysis of fenthion and its metabolites in various crops.

The susceptibility levels of Malaysian Aedes albopictus larvae sampled from several agricultural, fogging-free residential and dengue prone residential areas against different larvicides were evaluated using revised diagnostic doses derived from the 2xLC99 values of the reference strain. Upon 24-hour recovery period of WHO larval bioassay, incipient resistance was observed among Ae. albopictus larvae from rubber estates against fenitrothion (96.67% mortality) and permethin (97.00% mortality) while Ae. albopictus larvae from rice cultivation areas were moderately resistant to fenthion (94.33% mortality). Aedes albopictus larvae from dengue prone residential areas developed moderate to high resistance against dichlorodiphenyltrichloroethane (DDT), fenitrothion, fenthion, propoxur and permethrin (79.67% - 97.33% mortality). Moderate to high resistance were also demonstrated among all populations of Ae. albopictus larvae against temephos and chlorpyrifos (63.00% - 97.67% mortality). Except for Ae. albopictus larvae from oil palm plantations, all Ae. albopictus larval populations were also highly resistant to bendiocarb (65.67% - 89.67% mortality). Cross resistance between larvicides from similar and different insecticide classes were also revealed in this study. The use of revised diagnostic doses established from the local reference strain could reduce the possibility of underestimation or overestimation of the insecticide susceptibility status of field strain populations.

Objective: The epidemiological evidence of human exposure to organophosphorus pesticides (OPPs) with type 2 diabetes mellitus (T2DM) and prediabetes (PDM) is scarce. We aimed to examine the association of T2DM/PDM risk with single OPP exposure and multi-OPP co-exposure., Methods: Plasma levels of ten OPPs were measured using the gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS) among 2734 subjects from the Henan Rural Cohort Study. We used generalized linear regression to estimate odds ratios (ORs) or β with 95% confidence intervals (CIs), and constructed quantile g-computation and Bayesian kernel machine regression (BKMR) models to investigate the association of OPPs mixture with the risk of T2DM and PDM., Results: High detection rates ranged from 76.35% (isazophos) to 99.17% (malathion and methidathion) for all OPPs. Several plasma OPPs concentrations were in positive correlation with T2DM and PDM. Additionally, positive associations of several OPPs with fasting plasma glucose (FPG) values and glycosylated hemoglobin (HbA1c) levels were observed. In the quantile g-computation, we identified significantly positive associations between OPPs mixtures and T2DM as well as PDM, and fenthion had the greatest contribution for T2DM, followed by fenitrothion and cadusafos. As for PDM, the increased risk was largely explained by cadusafos, fenthion, and malathion. Furthermore, BKMR models suggested that co-exposure to OPPs was linked to an increased risk of T2DM and PDM., Conclusion: Our findings suggested that the individual and mixture of OPPs exposure were associated with an increased risk of T2DM and PDM, implying that OPPs might act an important role in the development of T2DM., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

Abstract: An acryloyl β‐cyclodextrin‐silica hybrid monolithic column for pipette tip solid‐phase extraction and high‐performance liquid chromatography determination of methyl parathion and fenthion has been prepared through a sol–gel polymerization method. The synthesis conditions, including the volume of cross‐linker and the ratio of inorganic solution to organic solution, were optimized. The prepared monolithic column was characterized by thermogravimetric analysis, scanning electron microscopy, and Fourier transform infrared spectroscopy. The eluent type, volume and flow rate, sample volume, flow rate, acidity, and ionic strength were optimized in detail. Under the optimized conditions, a simple and sensitive pipette tip solid‐phase extraction with high‐performance liquid chromatography method was developed for the determination of methyl parathion and fenthion in lettuce. The method yielded a linear calibration curve in the concentration ranges of 15–400 μg/kg for methyl parathion and 20–400 μg/kg for fenthion with correlation coefficients of above 0.9957. The limits of detection were 4.5 μg/kg for methyl parathion and 6.0 μg/kg for fenthion, respectively. The recoveries of methyl parathion and fenthion spiked in lettuce ranged from 96.0 to 104.2% with relative standard deviations less than 8.4%. [ABSTRACT FROM AUTHOR]

The ubiquity of pollutants, such as agrochemicals and heavy metals, constitute a serious risk to human health. To evaluate the induction of DNA damage and programmed cell death (PCD), root cells of Allium cepa and Vicia faba were treated with two organophosphate insecticides (OI), fenthion and malathion, and with two heavy metal (HM) salts, nickel nitrate and potassium dichromate. An alkaline variant of the comet assay was performed to identify DNA breaks; the results showed comets in a dose-dependent manner, while higher concentrations induced clouds following exposure to OIs and HMs. Similarly, treatments with higher concentrations of OIs and HMs were analyzed by immunocytochemistry, and several structural characteristics of PCD were observed, including chromatin condensation, cytoplasmic vacuolization, nuclear shrinkage, condensation of the protoplast away from the cell wall, and nuclei fragmentation with apoptotic-like corpse formation. Abiotic stress also caused other features associated with PCD, such as an increase of active caspase-3-like protein, changes in the location of cytochrome C (Cyt C) toward the cytoplasm, and decreases in extracellular signal-regulated protein kinase (ERK) expression. Genotoxicity results setting out an oxidative via of DNA damage and evidence the role of the high affinity of HM and OI by DNA molecule as underlying cause of genotoxic effect. The PCD features observed in root cells of A. cepa and V. faba suggest that PCD takes place through a process that involves ERK inactivation, culminating in Cyt C release and caspase-3-like activation. The sensitivity of both plant models to abiotic stress was clearly demonstrated, validating their role as good biosensors of DNA breakage and PCD induced by environmental stressors. [ABSTRACT FROM AUTHOR]

Dynamic surface-enhanced Raman spectroscopy (D-SERS) based on the state change of the substrate not only significantly enhances but also provides a highly reproducible Raman signal. Hence, we develop a fast and accurate method for the detection of fenthion on fruit and vegetable peel using D-SERS and random forests (RF) with variable selection. With uniform Ag nanoparticles, the dynamic spectra of fenthion solution at different concentrations were obtained using D-SERS, and fenthion solution greater than or equal to 0.05 mg/L can be detected. Then, the quantitative analysis models of fenthion were developed by RF with variable selection for spectra of different range. The model of best performance is developed by RF and spectra of characteristic range with higher RF importance (top 40%), and the root mean square error of cross-validation is 0.0101 mg/L. Moreover, the fenthion residue of tomato, pear, and cabbage peel were extracted by a swab dipped in ethanol and analyzed using the above method to further validate the practical effect. Compared to gas chromatography, the maximal relative deviation is below 12.5%, and the predicted recovery is between 87.5% and 112.5%. Accordingly, D-SERS and RF with variable selection can realize the fast, simple, ultrasensitive, and accurate analysis of fenthion residue on fruit and vegetable peel. [ABSTRACT FROM AUTHOR]

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This study aimed to describe the relationship between viral infection in Nilaparvata lugens (Stål), the brown planthopper (BPH), and different insecticide susceptibilities. BPH-resistant strains were selected using fenthion (an organophosphate) or etofenprox (a pyrethroid); a susceptible strain was used as the baseline colony before insecticide selection. All strains were infected with rice ragged stunt virus (RRSV) or rice grassy stunt virus (RGSV), after which the activities of three detoxification enzymes, cytochrome-P450-monooxygenase (P450), glutathione S-transferase (GST), and carboxylesterase (CE), were compared. Males of the strains selected for both insecticides showed high P450 and GST-CDNB activities. The activity of all enzymes was higher in males than in females, as a whole. However, males of the susceptible strain infected with RRSV showed decreased CE and GSTCDNB activities. BPH with low susceptibility to etofenprox showed a marked increase in P450 activity after RRSV infection; the GST-CDNB activity of females in the insecticide-resistant strain increased. RGSV infection induced high CE and P450 activities in etofenprox-selected females. The RRSV infection rate, but not the RGSV, decreased in etofenprox-selected strains. [ABSTRACT FROM AUTHOR]

In this work a direct, simple, fast and sensitive method to determine Fenthion was developed using a Boron-Doped Diamond Electrode and Square Wave Voltammetry. The method was applied into Passiflora alata herbal medicinal tinctures derivate from passion fruits. None previous treatment such as derivation or pre-concentration of the analyte was done. Cyclic Voltammetry results showed well defined irreversible oxidation peaks at around 1.27 V into the pH range of 2.0 to 8.0. Square Wave Voltammetry was used to analytical determination and the analysis parameters, such as frequency, amplitude and pH from support electrolyte were optimized. A calibration curve was obtained and it was observed a sensitivity of 0.38 A/mol L-1 and linearity of 0.995. The limits of detection and quantification were 8.0x10-8 mol L-1 (21 μg L-1) and 2.5x10-7 mol L-1 (70 μg L-1), respectively. Recovery studies were applied using Passiflora alata samples fortified with Fenthion in concentrations of 2.5 μmol L-1and 4.0 μmol L-1, followed by the standard addition of the pesticide aliquots. It was observed that the complex matrix does not interferes in the method. The recovery results were about 98.4 and 112.0%, reinforcing that the method is suitable to determine the analyte in target complexes samples, such as Herbal Medicinal Plants. [ABSTRACT FROM AUTHOR]

Fenthion is a widely used organophosphorus pesticide in agriculture that induces different cytotoxic effects, including male reproductive toxicity. The present work aimed to study the ameliorative effects of curcumin, a potential therapeutic agent against several chronic diseases, on reproductive toxicity induced by the organophosphate insecticide fenthion. Forty adult male albino rats were divided into four groups. The control group received distilled water. The curcumin group was administered curcumin at a dose of 100 mg kg−1body weight. The fenthion group was administered fenthion at a dose of 0.001 mg kg−1. The fenthion/curcumin group was administered fenthion and curcumin together at the same doses. After four weeks of daily oral administration, the animals were sacrificed and their testes were excised. Specimens were processed for histopatholological and immunohistochemical investigations. Light and electron microscopic analysis visualised dramatic degenerative changes in seminiferous tubules as indicated by atrophy, necrosis, vacuolation and decreased number of spermatogenic cells. Moreover, the fenthion group showed a significant reduction in the proliferating cell nuclear antigen (PCNA)-immunoreactivity. Decreased PCNA-immunoreactivity reflected the depletion in the proliferation rate of spermatogenic cells and suggesting arrested spermatogenesis. Curcumin administration to fenthion-treated rats revealed mild degenerative changes with partial improvement of active spermatogenesis. In conclusion, these data may confirm the cytoprotective potency of curcumin against fenthion-induced cyto-toxicity. [ABSTRACT FROM PUBLISHER]

Background: Acute high dose exposure to teratogenic chemicals alters the proper development of an embryo leading to infertility, impaired fecundity, and few viable offspring. However, chronic exposure to sub-toxic doses of teratogens during early development may also have long-term impacts on egg quality and embryo viability. Methods: To test the hypothesis that low dose exposure during early development can impact long-term reproductive health, Caenorhabditis elegans larvae were exposed to 10 teratogens during larval development, and subsequently were examined for the pattern of egg-laying and egg quality (hatched larvae and embryo viability) as gravid adults. After the exposure, adult gravid worms were transferred to untreated plates and the numbers of eggs laid were recorded every 3 hours, and the day following exposure the numbers of hatched larvae were counted. Re sults: While fecundity and fertility were typically impaired by teratogens, unexpectedly, many teratogens initially increased egg-laying at the earliest interval compared to control but not at later intervals. However, egg quality, as assessed by embryo viability, remained the same because many of the eggs (Conclusions: Chronic, low dose exposures to teratogens during early larval development have subtle, long-term effects on egg laying and egg quality.

Fenthion is one of the most widely used organophosphate insecticides for the control of many varieties of pests in Nigeria. The genotoxic effect of the pesticide was evaluated in the blood erythrocytes ofClarias gariepinususing the micronucleus (MN) test. The oxidative stress parameters were also studied in the liver and gill tissues. Fish were exposed to 2.0, 4.0, and 8.0 mgL−1of fenthion and sampling was done on days 1, 7, 14, 21 and after 7-day recovery. Micronuclei induction was highest (7.55) on day 14 at all concentrations in the peripheral blood cells. Oxidative stress was evidenced by increased lipid peroxidation (LPO). Maximum LPO values of 62.47% and 71.17% were observed in the gill and liver tissues respectively inC. gariepinusexposed to 8.0 mgL−1concentration of fenthion. There were alterations in the values of reduced glutathione (GSH), glutathione reductase (GR), glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT) during the exposure and recovery periods. The 7-day recovery period was not adequate to eliminate fenthion-induced changes as LPO, CAT, and GR activity remain elevated. However, MN frequency and activity of SOD, GSH, and GPx (except at 8.0 mgL−1) recovered. The present findings give further credence on the integrated use of MN test and oxidative stress parameters in risk assessment of pollutants in aquatic ecosystem. [ABSTRACT FROM PUBLISHER]

The susceptibility values for field-collected (BG-BG) and laboratory (KS-BG) strains of German cockroaches (BS-BG), Blattella germanica (L.) to five synthetic pyrethroid and three organophosphate insecticides were assessed by topical application. Both KS-BG and BS-BG strains demonstrated the highest levels of susceptibility to deltamethrin with LD50 values of 0.0035 μg/female and 1.5744 μg/female, respectively. The KS-BG strain demonstrated the lowest susceptibility level to fenthion with an LD50 value of 0.0698 μg/female, while the BS-BG field population showed the lowest susceptibility to bifenthrin with 4.6811 μg/female. The BS-BG field population showed resistance levels of 50 to 640 fold higher against the eight pesticides evaluated compared to the KS-BG strain. The resistance ratios (RR) of the eight pesticides were compared using populations of B. germanica that were collected from the same locality during 2007 and 2014. The field population of B. germanica collected during 2014 demonstrated significantly high resistance to an organophosphates and all pyrethroids when compared with those collected during 2007, but RR values were <10 except for chlorpyrifos-methyl and chlorpyrifos with RR values of 74 and 104, respectively. [ABSTRACT FROM AUTHOR]

This study investigated alternative in-field chemical controls against Bactrocera tryoni (Froggatt). Bioassay 1 tested the mortality of adults exposed to fruit and filter paper dipped in insecticide, and the topical application of insecticide to adults/fruit. Bioassay 2 measured the mortality of adults permitted to oviposit on fruit dipped in insecticide and aged 0, 1, 3, or 5 days, plus the production of offspring. Bioassay 3 tested infested fruit sprayed with insecticide. The field bioassay trialed the mortality of adults exposed to one- and five-day insecticide residues on peaches, and subsequent offspring. Abamectin, alpha-cypermethrin, clothianidin, dimethoate (half-label rate), emamectin benzoate, fenthion (half- and full-label rate), and trichlorfon were the most efficacious in bioassay 1, across 18 tested insecticide treatments. Overall, the LT50 value was lowest for fenthion (full-label rate), clothianidin, and alpha-cypermethrin. Fenthion, emamectin benzoate, and abamectin had the greatest effect on adult mortality and offspring production. Infested fruit treated with acetamiprid, fenthion, and thiacloprid produced no/very few offspring. Alpha-cypermethrin demonstrated good field efficacy against adults (one day post treatment: 97.2% mortality, five day post treatment: 98.8% mortality) and subsequent offspring (100% across one and five day post treatments), comparable to that of fenthion (full-label rate) (100% mortality for offspring and adults across both post treatments). Alpha-cypermethrin is a possible alternative to fenthion against B. tryoni; as a pyrethroid, it may not be desirable if adjunct biological control is imperative. Thiacloprid and Acetamiprid may be useful as a post-harvest treatment. [ABSTRACT FROM AUTHOR]

Oxidation and reduction processes of the insecticide fenthion was comparatively investigated at a reduced graphene oxide modified glassy carbon electrode (RGO-GCE) and a cyclic renewable silver amalgam film electrode (Hg(Ag)FE) using square wave stripping voltammetry (SWSV). The influence of pH and SW parameters was investigated. The linear concentration ranges were found to be 1 × 10−6 - 2 × 10−5 and 1 × 10−7 - 2 × 10−5 mol L−1 for Hg(Ag)FE and RGO-GCE, respectively. The detection and quantification limits were calculated as 1.3 × 10−7 and 4.5 × 10−7 mol L−1 for Hg(Ag)FE and 7.6 × 10−9 and 2.5 × 10−8 mol L−1 for RGO-GCE. Both of the developed electroanalytical methods offer rapid and simple detection of fenthion and were used on spiked tap and river water and apple juice samples. Scanning electron microscopy was used for RGO-GCE surface characterization. [ABSTRACT FROM AUTHOR]

The authors report on a surface molecular imprinting strategy for synthesizing magnetic and molecularly imprinted core-shell polymer nanoparticles (MMIPs) with a typical size of 320 nm. The triazophos-imprinted polymer shell on 180-nm magnetite particles (modified with 3-methacryloxypropyl trimethoxysilane) was obtained by radical polymerization of ethylene glycol dimethacrylate in the presence of triazophos, this followed by extractive removal of triazophos. The resulting MMIPs possess large binding capacity, high recognition selectivity, and fast binding kinetics for triazophos. They can be easily separated from a solution by using a magnet. These features result in a convenient and selective solid-phase extraction procedure for triazophos prior to its determination by UV spectrometry or by GC analysis. The method was successfully applied to the extraction and clean-up of triazophos residues in spiked homogenates of vegetables with recoveries in the range of 89.2 ~ 99.0%. The detection limits for triazophos by the UV assay and GC assay are 0.93 nM and 0.32 nM, respectively. [ABSTRACT FROM AUTHOR]

• Immobilisation of human FMO1 on glassy carbon electrode with cation surfactant DDAB. • Contact angle and AFM surface measurements of graphene oxide-DDAB. • Enhanced electrochemical signal of FMO1 in presence of graphene oxide. • FMO1 bioelectrode activity towards pesticides; phorate, methiocarb and fenthion. • Successful tandem oxidation of phorate with FMO1 and CYP3A4 bioelectrodes. It is highly advantageous to devise an in vitro platform that can predict the complexity of an in vivo system. The first step of this process is the identification of a xenobiotic whose monooxygenation is carried out by two sequential enzymatic reactions. Pesticides are a good model for this type of tandem reactions since in specific cases they are initially metabolised by human flavin-containing monooxygenase 1 (hFMO1), followed by cytochrome P450 (CYP). To assess the feasibility of such an in vitro platform, hFMO1 is immobilised on glassy carbon electrodes modified with graphene oxide (GO) and cationic surfactant didecyldimethylammonium bromide (DDAB). UV–vis, contact angle and AFM measurements support the effective decoration of the GO sheets by DDAB which appear as 3 nm thick structures. hFMO1 activity on the bioelectrode versus three pesticides; fenthion, methiocarb and phorate, lead to the expected sulfoxide products with K M values of 29.5 ± 5.1, 38.4 ± 7.5, 29.6 ± 4.1 µM, respectively. Moreover, phorate is subsequently tested in a tandem system with hFMO1 and CYP3A4 resulting in both phorate sulfoxide as well as phoratoxon sulfoxide. The data demonstrate the feasibility of using bioelectrochemical platforms to mimic the complex metabolic reactions of xenobiotics within the human body. [ABSTRACT FROM AUTHOR]