Acephate Residues Research Articles

Validation and efficacy of various decontamination solutions in eliminating acephate residues from okra

The experiments were carried out to validate an analytical method and to examine the impact of various decontaminating solutions on the removal of acephate residues from okra. Acephate analysis was performed using HPLC-UV, and sample extraction was done using the QuEChERS method. Method validation encompassed assessing specificity, linearity, precision, accuracy, as well as limits of detection (LOD) and quantification (LOQ). The method exhibited excellent linearity with R2 values ≥ 0.99. LOD and LOQ were determined at 0.5 µg mL−1 and 2 µg mL−1, respectively. The results indicated average recoveries ranging from 80.2% to 83.3% with a % RSD below 5%. The decontamination procedures include rinsing with running tap water, soaking in lukewarm water, 2% CH3COOH, 1% NaCl, 5% NaHCO3, 0.01% KMnO4, and in commercially available decontamination products such as nimwash, veggie clean, and arka herbiwash for a duration 10 minutes. Among all the treatments, soaking in nimwash solution showed remarkable effectiveness (96.75% removal), followed by veggie clean (94.97% removal) and arka herbiwash (95.80% removal). Washing okra samples in running tap water was found to be the least effective compared to other treatments.

Enhancing the photocatalytic elimination of acephate residues using Ni0 doped and diatomite-supported NiO: optimization, pathway, and toxicity

NiO nanoparticles were synthesized and modified with Ni0 in the form of Ni/NiO blend and supported on a porous diatomite substrate, forming hybrid structures of NiO/D and Ni@NiO/D with enhanced photocatalytic performances.

Enantioseparation and dissipation of acephate and its highly toxic metabolite methamidophos in pakchoi by supercritical fluid chromatography tandem mass spectrometry.

Acephate is widely used in crops as racemate. However, the enantioselective dissipation of acephate enantiomers has not been investigated in pakchoi. A sensitive and effective approach was established for determining residues of acephate and its highly toxic metabolite methamidophos enantiomers by supercritical fluid chromatography tandem mass spectrometry. Baseline separations for their enantiomers were achieved by using a Chiralcel OD-H column. The optimal chromatographic conditions were obtained as follows: CO2 /ethanol (95/5) as mobile phase; flow rate, 3.0mL/min; column temperature, 40°C. The mean recoveries (RSDs) of analytes were in the range of 77-83.1% (6.1-9.9%), 75.4-87.5% (9.3-13.2%), and 81.5-84.2% (7.1-13.4%) at three fortification levels (0.005, 0.05, and 0.5mg/kg for each enantiomer) for interday assay (n=18). The method was used to evaluate the enantioselective dissipation of acephate and methamidophos in pakchoi. S-acephate dissipated faster than R-acephate, while the concentration of R-methamidophos was higher than that of S-methamidophos during the entire study period. The results indicated that the R-enantiomer of acephate and methamidophos was preferentially enriched in pakchoi. The established analysis approach and the study data provided useful information for the rational use of acephate in agriculture.

Pesticide residues analysis in farm gate vegetables of agricultural areas in Tumakuru district, Karnataka, India

The main purpose of this experiment was to understand pesticide residues persistence and their toxicity level in vegetables. In the present study pesticide residues in tomato (Solanum lycopersicum) and capsicum (Capsium annuum L.) vegetables cultivated in Tumakuru, Gubbi, Kunigal and Pavagada taluks in Tumkur district were analysed. In methodology, samples of 1 kg each were collected, cut into small pieces, macerated in a grinder and used for the analysis. Pesticides were quantified by gas chromatography-mass spectrometry (GC-MS). Results showed tomato samples of Pavagada recorded acephate (0.346 mg/kg), dichlorvos (0.189 mg/kg), fenvalerate (0.057 mg/kg) and Tumakuru samples recorded phorate (0.072 mg/kg) residues higher than MRLs (Maximum residue levels). Chlorpyrifos, cyhalothrin-g and cypermethrin were below detection level (BDL) in all the samples. Cyfluthrin-β recorded highest in Kunigal samples (0.294 mg/kg), Tumakuru and Gubbi samples showed BDL. Deltamethrin was highest in Pavagada (0.296 mg/kg) samples and Tumakuru and Kunigal samples revealed BDL. Pavagada samples (0.026 mg/kg) showed monocrotophos residues higher than MRLs. In capsicum samples, acephate residue was highest in Tumakuru samples (0.333 mg/kg), highest chlorpyrifos (0.153 mg/kg) in Kunigal samples, deltamethrin (0.381 mg/kg), fenvalerate (0.168 mg/kg) and phorate (0.089 mg/kg) residues were higher than MRLs in Pavagada samples. Cyfluthrin-β (0.045 mg/kg) was high in Tumakuru and dichlorvos (0.042 mg/kg) high in Pavagada samples. Cyhalothrin-g, cypermethrin and monocrotophos were BDL in all the samples. An attempt has been made to assess the different pesticides usage and their adverse impacts on vegetables, which are backbone to afford assistance for an extensive array of investigators.

Monitoring of pesticide residues in vegetables collected from retail markets of Dhaka district of Bangladesh using QuEChERS Extraction and Gas Chromatography

The present study was aimed to detect and quantify major organophosphorus pesticide residues in cauliflower and cucumber collected from different retail markets of Dhaka city, Bangladesh. In this study, a total of 50 vegetable samples (30 samples of cauliflower and 20 samples of cucumber) were analyzed using Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) extraction technique and Gas Chromatography coupled with Flame Thermionic Detector (GC-FTD). Among the 30 analyzed samples of cauliflower, 5 samples (16.7% of the total number of samples) contained residues of chlorpyrifos, quinalphos, acephate and dimethoate, where 4 samples contained multiple pesticide residues. All the contaminated samples of cauliflower contained residues above the EU-MRL. On the other hand, among the 20 analyzed samples of cucumber, only 2 samples (10% of the total number of samples) contained residues of quinalphos and chlorpyrifos at a level being below the EU-MRL. This study reflects the overall scenario of pesticide residues remain in cauliflower and cucumber purchased from different local markets of Dhaka city, which will help the consumer to be aware of their health and safety. The findings derived from this study reveals the public health concern due to the potential of pesticide toxicity in vegetables for the consumers. Therefore, continuous monitoring on the use of pesticides in vegetables should be strengthened. Asian Australas. J. Food Saf. Secur. 2021, 5 (2), 63-70

Organophosphorus pesticide residues detected in eggplant and tomato samples collected from different regions of Bangladesh

The study was conducted to detect and quantify the residue of seven commonly used organophosphorus pesticides (acephate, chlorpyrifos, quinalphos, diazinon, malathion, dimethoate and fenitrothion) in eggplant and tomato samples collected from local market of commercially grown four different regions viz. Bogura, Narsingdi, Jeshore and Cumilla for the comparison between the detected residue level with maximum residue limit (MRL) set by European Union. A total of 80 analyzed samples of eggplant and tomato, 21.25% of the total number of samples contaminated with acephate, chlorpyrifos, fenitrothion and diazinon residues which were above the EU-MRLs. Out of 40 analyzed samples of eggplant, 11 samples were contaminated with acephate, diazinon fenitrothion and chlorpyrifos residues. All of the contaminated samples (27.5% of the total number of samples) had chlorpyrifos (0.02-0.046), acephate (0.017-0-0.39), diazinon (0.11-0.47) and fenitrothion (0.20) residues which were above the EU-MRLs. The eggplant samples collected from Jeshore and Narsingdi received more pesticides than Cumilla and Bogura regions. In case of 40 analyzed samples of tomato, 6 samples (15% of the total number of samples) had chlorpyrifos (0.27-0.43), diazinon (0.25) and fenitrothion (0.10) residues which were above EU-MRLs. Malathion, quinalphos and dimethoate residues were not found in any of the tested samples which might be applied at recommended doses. Asian Australas. J. Food Saf. Secur. 2021, 5 (1), 27-31

Organophosphate and carbamate pesticide residues and accompanying risks in commonly consumed vegetables in Kenya

ABSTRACT The current study was conducted to assess the levels of organophosphates and carbamates in vegetables in Kenya and to examine potential consumer health risks. A total of 90 samples were analysed by liquid chromatography/high-resolution tandem mass spectrometry. Residues of acephate, chlorpyrifos, methamidophos, omethoate and profenofos were found in 22% of the samples, ranging from 10 to 1343 μg/kg. The EU MRL was exceeded in 21%, 10%, 8% and 22% of the samples of French beans, kales, spinach and tomatoes, respectively. Chlorpyrifos in spinach had an acute HQ of 3.3 and 2.2 for children and adults, respectively, implying that potential health risks with respect to acute dietary exposure cannot be excluded. For chronic dietary exposure, all chronic HQs were below 1. The HI for the pesticides was 0.54 and 0.34 for children and adults. Routine monitoring of OPs and carbamates in vegetables is recommended to minimise consumer’s health risks.

DETERMINATION OF SPIROMESIFEN, QUINOLPHOS, MONOCROTOPHOS, CARBENDAZIM AND ACEPHATE RESIDUE BEHAVIOUR IN OKRA (ABELMOSHUS ESCULENTUS) BY LIQUID CHROMATOGRAPHY AND MASS SPECTROPHOTOMETRY AND THEIR DECONTAMINATION USING HOUSE HOLD PROCESSES

Objective: Field experiments were conducted at Agricultural University, Rajendra Nagar, Hyderabad, Telanagana to study the dissipation kinetics of carbendazim, monocrotophos, spiromesifen, acephate and quinalphos in okra fruit. Decontamination study was also conducted to evaluate quality of okra pods by reducing the residues of carbendazim, monocrotophos, spiromesifen, acephate and quinalphos by using different processes such as 2% salt solution, acetic acid, biowash, butter milk, cooking, drying, Formula 1(T7), frying, lemon water, sodium bicarbonate, tamarind water and tap water.
 Methods: All the pesticide residues with one test dose at two spray i.e., first spray at flowering stage and second spray after an interval of ten days was carried out. The samples drawn at specific periods were analyzed by liquid chromatography and mass spectrophotometry (LC-MS/MS).
 Results: The initial deposit of carbendazim, monocrotophos, spiromesifen, acephate and quinalphos in okra was found to be 2.239, 2.586, 2.401, 1.39, 0.78 mg/kg respectively. More than 98 % of carbendazim, spirofesifin, acephate and quinolphos dissipated after 15 d and monocrotophos was dissipated after 10 d. Sodium bicarbonate and 2% salt solution are the best methods for decontamination after cooking. The decontamination values of frying and formula 1 seems to be almost same. After these two methods biowash thought to be the method of choice.
 Conclusion: These results are helpful in setting up maximum residual limit (MRLs) of these pesticides in okra in India. From the results, it could be recommended that cooking suits best for almost all of the pesticide residues.

Dynamic surface-enhanced Raman spectroscopy for the detection of acephate residue in rice by using gold nanorods modified with cysteamine and multivariant methods

Dynamic surface-enhanced Raman spectroscopy (D-SERS) was employed for the rapid detection of acephate in rice with simply regulated gold nanorods. Gold nanorods modified with cysteamine were prepared to circumvent the weak affinity of acephate molecules to the gold surface for a gigantic and stable enhancement. D-SERS was adopted to measure spectra of acephate residue at a range of 100.2–0.5 mg/L in rice samples, and the low residue of 0.5 mg/L can be still detected. Multivariant methods in machine or deep learning were used to develop the regression models for the automatic analysis of acephate residue level. Partial least squares regression and principal component analysis obtained the optimal performance with the root-mean-square error (RMSE) of validation of 5.4776, coefficient of determination (R2) of validation of 0.9560, RMSE of prediction of 6.2845, and R2 of prediction of 0.9541. Thus, the proposed method provides accurate and sensitive detection for acephate in rice.

Qualitative analysis of insecticide residue in cauliflower samples collected from different regions of Bangladesh

The samples of the cauliflowers were analyzed to assess the residue level of six insecticides (i.e.; cypermethrin, quinalphos, diazinon, malathion, fenitrothion and acephate) using GC-FTD and GC-ECD method. Out of analyzed 75 collected samples of cauliflower from farmer’s field of Jessore, Gazipur and Rangpur, 38.67% (29 from 75) were found to be contaminated with the insecticides. Many samples contained cypermethrin, acephate and fenitrothion residues. Quinalphos, acephate and fenitrothion were found as multiple product residues representing 13.79% (4 from 29) of the total contaminated samples and the rest 86.21% contained single insecticide residue. About 13.33% (10 of 75) of the total samples had residues exceeding the MRL (Maximum Residue Limit) irrespective of single or multiple insecticide residues. Malathion residue was found only in one sample from Jessore. Two samples showed diazinon residue one from Jessore and the other one from Rangpur location. The detected residue levels of both malathion and diazinon were below the MRL, which might be due to higher rate of degradation. The presence of highest residue levels of insecticides in cauliflowers may be due to its irrational and repeated use before harvest.
 Asian Australas. J. Food Saf. Secur. 2018, 2(1), 29-34

Fate of acephate and its toxic metabolite methamidophos during grape processing

This study aimed to determine the degradation of acephate and its metabolite methamidophos during different kinds of grape processing, using a simple gas-chromatographic method with a flame photometry detector. During wine processing, there was no significant effect of crushing, pressing, and clarification on the removal of acephate and methamidophos, whereas 58.9% acephate was dissipated during the fermentation step. Aging and bottling resulted in a reduction of 43.2% and 30.6% for acephate and methamidophos, respectively. The processing factors (PFs) of acephate during the wine process were <1, whereas those of methamidophos were >1. Moreover, washing with hydrogen peroxide solutions effectively reduced the levels of acephate and methamidophos present in the grape skin and pulp more than other washing solutions did (tap water, detergent solution, acetic acid solution, NaCl solution, and Na2CO3 solution). Finally, the best removal rate of acephate residue and the minimum methamidophos level was achieved at a fermentation temperature of 22.4 °C, yeast inoculum of 8.5‰, and pH of 3.8. These results suggest that the potential metabolites of parent pesticide should be paid more attention during wine processing.

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Influence of plant growth regulating substances on transport and degradation of acephate and its metabolite methamidophos in tomato

ABSTRACTThe occurrence of pesticides in vegetables such as tomato poses an increasing attention to their potential risk to human health. In this study, acephate and its metabolite methamidophos were investigated for their transport and degradation in tomato cultivated in spiking nutrient solutions containing acephate at 1 mg/L. Acephate was taken up and transported via xylems with the concentrations of 41–145 μg/L in xylem sap at 2 and 8 cm above the roots in control treatment. The residue levels of methamidophos derived from acephate were in a range of 0–4.21 μg/L, being 0.00–3.73% of the parent acephate. The influence of three plant growth regulating substances, 1-naphthylacetic acid (NAA), glucose and phlorizin, on the transport and degradation of acephate and methamidophos in tomato was evaluated. All of these substances had positive effects on the transport of acephate and methamidophos in tomato xylem system. The NAA or glucose treatment promoted the degradation of acephate to methamidophos; however, with the addition of phlorizin, the concentrations of acephate were reduced in comparison to that under glucose treatment, suggesting that phlorizin would cause an inhibitory effect on the transport of acephate in tomato plant. These results may indicate an effective approach to reduce acephate and methamidophos residues in tomato.

Bioefficacy and persistence of acephate in mungbean Vigna radiata (L.) Wilczek.

The bioefficacy, persistence and metabolism of foliar application of acephate 75 SP at the respective recommended and double doses of 1500 and 3000ga.i. ha(-1) were studied on kharif mungbean crop. Acephate gave a very effective control of the pod borer, Helicoverpa armigera (Hubner) at the tested doses on mungbean crop throughout the cropping season, besides recording lower percent pod damage and higher grain yield. The recommended dose of acephate also recorded higher net returns and thus indicating its superiority. Persistence of acephate in mungbean leaves and soil was studied following applications of acephate @ 1500 and 3000ga.i. ha(-1) at 30days after sowing. Residues of acephate in mungbean leaves and soil were estimated using gas liquid chromatograph (GLC) and confirmed on gas chromatograph-mass spectrometry (GC-MS). Half-life periods for acephate in mungbean leaves were observed to be 2.98 and 3.27days at single and double the application rates, respectively. Residues of acephate dissipated below its limit of quantification (LOQ) of 0.05mgkg(-1) after 20 and 25days at single and double the application dosage, respectively. Similarly, half-life periods for acephate in mungbean soil were observed to be 1.86 and 1.94days at single and double the application rates, respectively. Residues of acephate dissipated below its LOQ of 0.05mgkg(-1) after 10 and 15days at single and double the application dosage, respectively.

Molecularly imprinted polymer prepared by Pickering emulsion polymerization for removal of acephate residues from contaminated waters

ABSTRACTA molecularly imprinted polymer (MIP) prepared with Pickering emulsion polymerization was designed by a computational approach for removal of acephate from aqueous solution. Methacrylic acid, ethylene glycol dimethacrylate, and chloroform were screened as the optimal functional monomer, crosslinker, and porogen by the Gaussian 03 package using the density functional theory method. The polymerization was carried out in an oil‐in‐water emulsion using nano‐SiO2 particles as stabilizer instead of a toxic surfactant. The characterization results indicated that the prepared MIP had a porous and hollow core, and the particle size was approximately 20 μm. The binding and recognition abilities of MIP for acephate were studied through equilibrium adsorption analysis and selectivity analysis. The results showed that the MIP had high binding capacity and excellent selectivity for acephate. The saturated binding amount could reach 6.59 × 103 μg/g. The Langmuir isotherm model gave a good fit to the experimental data. Moreover, the results of a reusability analysis and practical application suggested that the prepared MIP provides the potential for removal of acephate residues from aqueous solution. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43126.

Biomimetic Enzyme-linked Immunosorbent Assay Using a Hydrophilic Molecularly Imprinted Membrane for Recognition and Fast Determination of Trichlorfon and Acephate Residues in Vegetables

This study describes the development of a new direct competitive enzyme-linked immunosorbent assay method with a hydrophilic imprinted film as biomimetic antibody for determining multi-pesticide residues. The imprinted film, which can selectively recognize trichlorfon and acephate, was synthesized directly on the surface of a 96-well plate using 4-(dimethoxyphosphorothioylamino) butanoic acid as the template molecule. This film exhibited antibody-like recognition ability, fast adsorption–desorption dynamics and good stability. Under optimal conditions, the sensitivity (IC50) of the biomimetic enzyme-linked immunosorbent assay (BELISA) method was 12.0 mg/L for trichlorfon and 30.0 mg/L for acephate. The limit of detection (LOD, IC15) was 8.0 μg/L for trichlorfon and 12.0 μg/L for acephate. The developed method was applied to the determination of the trichlorfon and acephate in the spiked asparagus and cucumber samples with recoveries ranging from 72.1 to 92.0 % for trichlorfon and 70.0 to 85.0 % for acephate.

Dissipation behavior and risk assessment of acephate in brinjal using GLC with FPD.

A study was conducted to observe the persistence, dissipation behavior, and risk assessment of acephate on brinjal fruit. Brinjal crop was sprayed with acephate 75 SP at 560 and 1120 g a.i. ha(-1) at fruiting stage followed by another application at 10-day interval. After sampling, the samples were extracted and cleaned up using quick, easy, cheap, effective, rugged, and safe (QuEChERS) technique, and the residues of acephate were analyzed with gas chromatography using flame photometric detector (FPD). The average initial deposits of acephate on brinjal fruits were found to be 2.54 and 4.07 mg kg(-1) following application of insecticide at 560 and 1120 g a.i. ha(-1), respectively. Residues of acephate reached below determination level of 0.10 mg kg(-1) after 7 days at recommended dosages and after 10 days at double the recommended dosages. The half-life of acephate was found to be 1.55 and 1.52 days, respectively, at 560 and 1120 g a.i. ha(-1). For risk assessment studies, theoretical maximum residue contributions (TMRC) were calculated and compared with maximum permissible intake (MPI). It was observed that TMRC values reached below MPI in 0-day samples at both recommended and double the recommended dosages. Therefore, it was concluded that if waiting period of 1 day is observed, there will be much reduced risk to consumers and the insecticide could be safely used for the protection of brinjal crop from insect pests.

Seasonal timing of neonicotinoid and organophosphate trunk injections to optimize the management of avocado thrips in California avocado groves

The timing of trunk injections of the organophosphate, acephate, and two systemic neonicotinoids, imidacloprid and dinotefuran, was evaluated in field trials for the management of avocado thrips. Following treatments, leaves were sampled over a 6-month period to determine the period of efficacy for each insecticide. The efficacy of acephate was determined using bioassays. Imidacloprid and dinotefuran residues in leaves were quantified by ELISA to determine the window of efficacy for these treatments based on previously determined biological dose response data. In addition, residues in fruit were quantified to determine whether trunk injection of insecticides might present a greater risk for contaminating fruit than traditional application methods. The timing of trunk injection treatments significantly impacted the uptake of imidacloprid and dinotefuran, with mid- and late-leaf flush periods proving more effective in terms of rate of uptake and degree of persistence at threshold levels. Acephate was mobilized very rapidly and gave good control of thrips in bioassays; however, residues of acephate, and its insecticidal metabolite methamidophos, were detected in the fruit for up to 4 weeks after injection. Imidacloprid was most effective when injected during the mid-flush period, which allowed levels to establish within the trees over a period of time when thrips would be actively feeding on young leaf tissue. The establishment of dinotefuran in trees was very rapid following trunk injection. However, its use was compromised by the inability of the chemical to reach effective concentrations for thrips control. Residues of dinotefuran were detected in fruit sampled from one tree, but the levels were below typical MRLs for other crops treated with this insecticide. Imidacloprid was not detected in any fruit sampled from trees in which imidacloprid had established in leaf tissue at concentrations that were toxic to avocado thrips. Overall, trunk injection of imidacloprid could be a viable option for avocado thrips control. However, residues of acephate in fruit may preclude its use because of the requirement for increased pre-harvest intervals. Dinotefuran injections may also be useful due to the rapid uptake and establishment within the canopy; however, it will be necessary to determine whether higher doses of dinotefuran can deliver the required levels of insecticide necessary for thrips control, without contaminating the fruit with residues.

A computational approach to design an electrochemical sensor and determination of acephate in aqueous solution based on a molecularly imprinted poly(o-phenylenediamine) film

A new molecularly imprinted polymer (MIP) electrochemical sensor was prepared by anchoring an imprinted insulating poly(o-phenylenediamine) film on a glassy carbon electrode (GCE) surface for the determination of acephate in aqueous solution. In this protocol, the selection of a functional monomer was performed computationally using the density functional theory method to evaluate the template–monomer interaction energy. The electrochemical properties of the MIP–GCE were characterized by cyclic voltammetry and alternating current impedance. Under optimal experimental conditions, the peak current of the MIP–GCE performed by differential pulse voltammetry was related to the concentration of acephate in the range from 5.0 × 10−7 to 1.0 × 10−4 mol L−1. The detection limit of 1.3 × 10−7 mol L−1 and the limit of quantitation of 4.5 × 1.0−7 mol L−1 were obtained. The prepared MIP–GCE showed high recognition, sensitivity to acephate, and it provides potential for monitoring acephate residues in foods and water samples.

Residues of pesticides acephate and methamidophos in capsicum grown in greenhouse and open field

Introduction Capsicum grown in low-cost polyhouses (a protective shade made up of polythene used for growing high-value agricultural products) is often infested by thrips and acephate is an insecticide, which is frequently and repeatedly used for controlling this pest. Objectives Since a polyhouse microclimate is different from that of an open field, a study was carried out to compare the decline pattern of acephate residues in capsicum grown in polyhouse to that grown in open field. Methods Laboratory standardized methodologies using gas liquid chromatography was adopted to estimate residues of acephate and its metabolite, methamidophos in capsicum fruits. Results and Conclusion Higher initial residues (0.39 ppm) and persistence of acephate (pre-harvest interval = 16 days) and its methamidophos metabolite was detected in capsicum grown in polyhouse as compared to that grown in open field (pre-harvest interval = 12 days) in spite of higher rate of growth and consequent residue ‘dilution’ in polyhouse-grown capsicum.