Carbamate Pesticides Research Articles

Background-free sensing platform for on-site detection of carbamate pesticide through upconversion nanoparticles-based hydrogel suit

On-site monitoring of carbamate pesticide in complex matrix remians as a challenge in terms of the real-time control of food safety and supervision of environmental quality. Herein, we fabricated robust upconversion nanoparticles (UCNPS)/polydopamine (PDA)-based hydrogel portable suit that precisely quantified carbaryl in complex tea samples with smartphone detector. UCNPS/PDA nanoprobe was developed by polymerization of dopamine monomers on the surface of NaErF4: 0.5% Tm3+@NaYF4 through electrostatic interaction, leading to efficient red luminescence quenching of UCNPS under near-infrared excitation, which circumvented autofluorescence and background interference in complicated environment. Such a luminescence quenching could be suppressed by thiocholine that was produced by acetylcholinesterase-mediated catalytic reaction, thus enabling carbaryl bioassay by inhibiting the activity of enzyme. Bestowed with the feasibility analysis of fluorescent output, portable platform was designed by integrating UCNPS-embedded sodium alginate hydrogel with 3D-printed smartphone device for quantitatively on-site monitoring of carbaryl in the range of 0.5–200 ng mL-1 in tea sample, accompanied by a detection limit of 0.5 ng mL-1. Owing to specific UCNPS signatures and hydrogel immobilization, this modular platform displayed sensitive response, portability and anti-interference capability in complex matrix analysis, thus holding great potential in point-of-care application.

Effects of carbamate pesticides intermediates on Escherichia coli membrane architecture: An in vitro and in silico approach.

Methyl isocyanate (MIC), a low molecular weight synthetic aliphatic compound, having an isocyanate group (−NCO), has industrial application. In this study, the effects of methyl isocyanate and its mechanism on outer membrane protein of Escherichia coli were observed using experimental and computational methods. In vitro exposure of N-succinimidyl N-methylcarbamate (NSNM) a synthetic analogue of MIC on E. coli to a final concentration of 2 mM was found to affect the growth curve pattern and changes in cell morphology. Molecular docking studies of MIC and NSNM with E. coli outer membrane protein (OmpW, OmpX, OmpF OmpA), and periplasmic domain (PAL) were performed. The in-silico results revealed that outer membrane protein OmpF showed the highest negative binding energy, i.e. ΔG −4.11 kcal/mole and ΔG −3.19 kcal/mole by NSNM and MIC as compared to other proteins. Our study concludes that methyl isocyanate retains lethal toxicity which leads to cell death due to the membrane protein damage of E. coli membrane.

Heterologous expression and exploration of the enzymatic properties of the carbaryl hydrolase CarH from a newly isolated carbaryl-degrading strain

Carbaryl is the representative of carbamate insecticide. As an acetylcholinesterase inhibitor, it poses potential threat to humans and other non-target organisms. Agrobacterium sp. XWY-2, which could grow with carbaryl as the sole carbon source, was isolated and characterized. The carH gene, encoding a carbaryl hydrolase, was cloned from strain XWY-2 and expressed in Escherichia coli BL21 (DE3). CarH was able to hydrolyze carbamate pesticides including carbaryl, carbofuran, isoprocarb, propoxur and fenobucarb efficiently, while it hydrolyzed oxamyl and aldicarb poorly. The optimal pH of CarH was 8.0 and the optimal temperature was 30 ℃. The apparent Km and kcat values of CarH for carbaryl were 38.01 ± 2.81 μM and 0.33 ± 0.01 s−1, respectively. The point mutation experiment demonstrated that His341, His343, His346, His416 and D437 are the key sites for CarH to hydrolyze carbaryl.

Co-Treatment of Copper Oxide Nanoparticle and Carbofuran Enhances Cardiotoxicity in Zebrafish Embryos.

The use of chemicals to boost food production increases as human consumption also increases. The insectidal, nematicidal and acaricidal chemical carbofuran (CAF), is among the highly toxic carbamate pesticide used today. Alongside, copper oxide nanoparticles (CuO) are also used as pesticides due to their broad-spectrum antimicrobial activity. The overuse of these pesticides may lead to leaching into the aquatic environments and could potentially cause adverse effects to aquatic animals. The aim of this study is to assess the effects of carbofuran and copper oxide nanoparticles into the cardiovascular system of zebrafish and unveil the mechanism behind them. We found that a combination of copper oxide nanoparticle and carbofuran increases cardiac edema in zebrafish larvae and disturbs cardiac rhythm of zebrafish. Furthermore, molecular docking data show that carbofuran inhibits acetylcholinesterase (AChE) activity in silico, thus leading to impair cardiac rhythms. Overall, our data suggest that copper oxide nanoparticle and carbofuran combinations work synergistically to enhance toxicity on the cardiovascular performance of zebrafish larvae.

Capturing Methomyl Droplet by Calix[4]arene Modified Surface

AbstractSelective recognition of carbamate pesticides on a superhydrophobic surface by the phenomenon of droplet rolling is a challenging topic. Here, the alkynyl‐calix[4]arene (AYC4) was synthesized, then self‐assembled on Si‐N3 modified silicon surface (AYC4‐SAMs) for rapid detection of methomyl. The AYC4‐SAMs exhibited high selectivity/sensitivity towards methomyl via visual water contact angle change with promising reusability, which is potential application for the identification and detection of pesticides.

Combination of cold induced HLLME with an effervescence-assisted DLLME based on deep eutectic solvent decomposition; application in extraction of some pyrethroid and carbamate pesticides from edible oils

ABSTRACT A cold-induced homogenous liquid–liquid microextraction method combined with solidification of floating organic droplets effervescent-assisted dispersive liquid–liquid microextraction has been developed for simultaneous extraction of several pyrethroid and carbamate pesticides from edible oils. The extracted analytes were determined by high performance liquid chromatography-diode array detector. For this purpose, 5 mL of edible oil sample was transferred into a glass test tube and it was mixed with 150 µL α-terpineol: acetic acid deep eutectic solvent. After vortexing (for 5 min), the mixture was placed into an ice: sodium chloride bath to adjust the solution temperature at −16℃. In this step, the oil sample was solidified, and the deep eutectic solvent was collected on top of the oil. Thus, it was collected and dispersed into 5.0 mL sodium carbonate solution at a concentration of 1.0 mol/L containing 2.5% w/v sodium chloride. In this step, the deep eutectic solvent was decomposed in the solution and α-terpineol dispersed in the sample solution. To obtain high extraction efficiency the effective parameters were optimised and under optimal conditions, the method showed broad linear ranges (2.6–500 ng/mL) with good coefficient of determinations ≥0.994. The extraction recoveries and enrichment factors of the method were in the ranges of 78–93% and 98–116%, respectively. The limits of detection and quantification were within the range of 0.2–0.8 and 0.6–2.6 ng/mL, respectively. The method was successfully used for the determination of the analytes in different edible oil samples.

A new method for predicting the acute toxicity of carbamate pesticides based on the perspective of binding information with carrier protein

Toxicity is one of the most important factors limiting the success of new drug development. In this paper, we built a fast and convenient new method (Carrier protein binding information-toxicity relationship, CPBITR) for predicting drug acute toxicity based on the perspective of binding information with carrier protein. First, we studied the binding information between carbamate pesticides and human serum albumin (HSA) through various spectroscopic methods and molecular docking. Then a total of 16 models were established to clarify the relationship between binding information with HSA and drug toxicity. The results showed that the binding information was related to toxicity. Finally we obtained the effective toxicity prediction model for carbamate pesticides. And the “Platform for Predicting Drug Toxicity Based on the Information of Binding with Carrier Protein” was established with the Back-propagation neural network model. We proposed and proved that it was feasible to predict drug toxicity from this new perspective: binding with carrier protein. According to this new perspective, toxicity prediction model of other drugs can also be established. This new method has the advantages of convenience and fast, and can be used to screen out low-toxic drugs quickly in the early stage. It is helpful for drug research and development.

A portable and automatic dual-readout detector integrated with 3D-printed microfluidic nanosensors for rapid carbamate pesticides detection

In the current study, we report here the design, fabrication and functional verification of a novel, portable and automatic dual-readout device for carbamate pesticides detection applications with low detection limits. This device integrated a 3D printed, low cost and disposable microfluidic chip to deliver nanomaterials and pesticides samples. Based on the cross-responsive mechanism and the agglomeration effect of AuNPs, two model signals (fluorescence and color change, dual-readout) were achieved from the response between pesticides and sensing materials. Simultaneously, a novel and unique fluorescence difference patterns (spectra-fingerprint) were produced based on cross-responsive mechanism for specificity recognition. The difference maps including color difference image and fluorescence difference spectra presented good selectivity among carbamate pesticides (six kinds of carbamate pesticides were successfully distinguished) or other categories in low concentration. By use of this dual-signal model, the device could achieve the lowest detectable concentrations for carbamate pesticides at ppb level with the practicability, reproducibility and stability estimated. Importantly, with the features of integration and instrumentation, the detector could be further employed for the home-based testing and environmental monitoring.

O-NE005. Electroneuromyography as a predictor of peripheral neuropathy symptoms after two years follow-up in farmers exposed to pesticide: A cohort study

Introduction . Farmer is one of the most common occupation in Indonesia. To increase crop production, they tend to use organophosphate or carbamate pesticides. These extensive pesticide uses could cause low cholinesterase levels in blood, and cause injury in peripheral nerve and neuropathy symptoms. With electroneuromyography (ENMG), subclinical neuropathy preceding its symptom could be found. The purpose of this study is to find association between any abnormality measurement in ENMG with neuropathic symptoms after two years. Methods . This was cohort prospective study. Farmers with history of pesticide exposure, without neuropathic symptoms in 2017, had low blood cholinesterase levels, and gave consent to have ENMG examination were recruited. Motor and sensory aspect of nerve was examined. For motor, we examined distal latency (DL), nerve conduction velocity (NCV), proximal amplitude (PA) and distal amplitude (DA) of median, ulnar, and tibial nerves. For sensory, we examined DL and PA of median, ulnar, and sural nerves. Neuropathic symptoms in 2 years follow up were determined from Total Neuropathic Symptoms Scale, with score > 0 diagnosed as having neuropathic symptoms. Results . There were 26 farmers included in this study. After statistical analyses, there were association between neuropathic symptoms after 2 years with motor NCV, motor PA and sensory DL of median nerve; motor NCV and motor PA of ulnar nerve (p-value > 0.05). After age, gender, working hour, pesticide spray duration adjustment, ENMG markers which had significant and independent association with neuropathy symptoms after two years were ulnar motor DL (p-value: 0.032), median motor NCV (p-value: 0.035), median motor PA (p-value: 0.043), and ulnar sensory DL (p-value: 0.010). Conclusion . From this study, we concluded that ENMG can be used as predictor for neuropathic symptoms in 2 years for asymptomatic farmers exposed to pesticide with low blood cholinesterase levels.

Conserved Metabolic and Evolutionary Themes in Microbial Degradation of Carbamate Pesticides.

Carbamate pesticides are widely used as insecticides, nematicides, acaricides, herbicides and fungicides in the agriculture, food and public health sector. However, only a minor fraction of the applied quantity reaches the target organisms. The majority of it persists in the environment, impacting the non-target biota, leading to ecological disturbance. The toxicity of these compounds to biota is mediated through cholinergic and non-cholinergic routes, thereby making their clean-up cardinal. Microbes, specifically bacteria, have adapted to the presence of these compounds by evolving degradation pathways and thus play a major role in their removal from the biosphere. Over the past few decades, various genetic, metabolic and biochemical analyses exploring carbamate degradation in bacteria have revealed certain conserved themes in metabolic pathways like the enzymatic hydrolysis of the carbamate ester or amide linkage, funnelling of aryl carbamates into respective dihydroxy aromatic intermediates, C1 metabolism and nitrogen assimilation. Further, genomic and functional analyses have provided insights on mechanisms like horizontal gene transfer and enzyme promiscuity, which drive the evolution of degradation phenotype. Compartmentalisation of metabolic pathway enzymes serves as an additional strategy that further aids in optimising the degradation efficiency. This review highlights and discusses the conclusions drawn from various analyses over the past few decades; and provides a comprehensive view of the environmental fate, toxicity, metabolic routes, related genes and enzymes as well as evolutionary mechanisms associated with the degradation of widely employed carbamate pesticides. Additionally, various strategies like application of consortia for efficient degradation, metabolic engineering and adaptive laboratory evolution, which aid in improvising remediation efficiency and overcoming the challenges associated with in situ bioremediation are discussed.

Communication—An Optical Fiber Biosensor Based on a Lab-on-a-Tip Approach for User-Friendly Carbosulfan Detection in Vegetable Samples

The use of a disposable pipette tip was studied to create a lab-on-a-tip approach. The configuration of a pipette tip, fiber optics, and paper-based biosensor show the compatibility of creating a novel one-shot optical biosensor for carbosulfan as carbamate pesticide. Under optimal experimental parameters, the lab-on-a-tip could detect carbosulfan in the linear range value of 10–22000 μg l−1 with a detection limit value of 10 μg l−1. The results show good agreement with the HPLC method.

Study of changes in the behaviour of Channa punctatus exposed to carbamate pesticide carbaryl

Present work was undertaken to study the behavioural alterations and morphological deformities in the freshwater fish Channa punctatus developed due to exposure to different sublethal concentrations of carbamate pesticide carbaryl. Channa punctatus were exposed to concentrations ranging between 0.1ppm to 1.31ppm in in vitro conditions in the laboratory. 100% mortality was observed due to exposure to 1.17 ppm or more concentrations of carbaryl. Below this concentration fish remained alive but several morphological and behavioral changes were observed. It shows that the change in the aquatic environment causes altered behavioural responses in the animals living in it. Channa punctatus in this toxic medium exhibited erratic movements, hyperactivity, restlessness, and loss of buoyancy and they started swimming at the surface of water. The response of the fish towards toxicity was dependent on concentration of carbaryl and length of exposure. The changes in behavioural parameters were both time and dose dependent.

Investigation of Residual Concentration of Organochlorine, Organophosphorus, and Carbamate Pesticides in Urban Drinking Water Networks of Hamadan Province, Iran

Pollution of water resources with pesticides is one of the environmental problems and a serious threat to the communities’ health. This study aimed to determine the residual concentration of pesticides in urban drinking water networks of Hamadan province in 2019. In order for investigating the residual concentration of organochlorine (aldrin, dieldrin, lindane, methoxychlor and permethrin), organophosphorus (chlorpyrifos, diazinon and malathion), and carbamate (atrazine and alachlor) pesticides in urban drinking water distribution networks of the province, a total of 46 samples were taken. The samples were analyzed by GC-ECD and the results were analyzed using Excel software (a descriptive cross-sectional study). The residues of aldrin, dieldrin, lindane, diazinon, malathion, atrazine, and alachlor were found in none of the samples. The maximum concentrations of chlorpyrifos and permethrin were 2.20 and 8.03 μg/L, respectively. The methoxychlor residue was observed only in one sample (C=0.35 μg/L) and all other samples were free of methoxychlor. Residues of studied pesticides in all samples are much less than the maximum allowable in the national standard and the World Health Organization (WHO) and Environmental Protection Agency (EPA) guidelines. Therefore, it can be concluded that the studied networks water quality as well as the urban drinking water resources in Hamadan province are at a very desirable level in terms of the pesticide residues. If the consumption of pesticides is not controlled, there is a possibility of increasing the concentration of these pollutants in water resources, which in turn may threaten the human health in the future.

Identification and Quantification of Soil Pesticides in Coastal Lakshmipur District of Bangladesh

This study was carried out to determine the presence and quantity of some selected pesticides from soil sediments collected from some ponds and canals located in the Lakshmipur district of Bangladesh. The high performance liquid chromatography (HPLC) technique was used to determine the concentration of pesticide residues. Some soil samples were found to be contaminated with carbamate (carbofuran and carbaryl) and organophosphorus (diazinon) pesticides. The concentration of carbofuran pesticide ranged from 0.303 μg/kg to 1.851 μg/kg. The highest concentration of carbofuran pesticide was found in SSP6 (1.851 μg/kg) and the lowest concentration was found in SSP9 (0.303 μg/kg). Carbaryl pesticide was found to be present in the sediment of only one pond, the concentration being 1.047 μg/kg. Organophosphorus (diazinon) pesticide was found in soil samples and the concentrations ranged from 0.147 μg/kg to 0.759 μg/kg, which were higher than the EEC-recommended limit of 0.1 μg/kg.
 Asiat. Soc. Bangladesh, Sci. 46(2): 191-200, December 2020

Enhanced Secretory Expression and Surface Display Level of Bombyx mori Acetylcholinesterase 2 by Pichia pastoris Based on Codon Optimization Strategy for Pesticides Setection.

The cholinesterase-based spectrophotometric assay, also called enzyme inhibition method, is a good choice for rapid detection of organophosphate pesticides (OPs) and carbamate pesticides (CPs). Obviously, the cholinesterase is the core reagent in enzyme inhibition method. In our previous work, a recombinant acetylcholinesterase 2 from Bombyx mori (rBmAChE2) was expressed in yeast successfully and exhibited great sensitivity. However, the yield of rBmAChE2 is not desirable. In this study, a codon optimization strategy was employed to enhance the yield of rBmAChE2 in Pichia pastoris GS115. Results showed that by replacing 6 key rare codons and increasing the percentage of bases G and C up to 46.85%, codon adaptation index (CAI) of Bombyx mori acetylcholinesterase 2 (bmace2) gene was improved from 0.70 to 0.81. After being transformed into Pichia pastoris GS115 via electroporation, the expression transformant can produce 139.7 U/mL secretory codon-optimized rBmAChE2 (opt-rBmAChE2) in the culture supernatant, 3.62 times higher than that of strain bearing the wild-type bmace2 gene. Meanwhile, opt-rBmAChE2 displayed on the yeast surface was up to 2280.02 U/g, 2.8 times higher than wild-type displayed rBmAChE2. In addition, either secretory or surface-displayed opt-rBmAChE2 maintained the similar sensitivities to the wild-type rBmAChE2 for tested inhibitors. Furthermore, the detection limits of the opt-rBmAChE2-based enzyme inhibition method for 10 kinds of OPs or CPs (0.01-2.69 mg/kg) were lower than most of the indexes present in current standard method (GB/T 5009.199-2003) or the maximum residue limits (GB 2763-2019) in China. The results might contribute to the utilization of rBmAChE2 for pesticide residue screening detection in practice.

Pesticide-induced changes in cholinesterase activity and chronic kidney disease of unknown etiology among farmers in Nakhon Ratchasima, Thailand

Chronic kidney disease of unknown etiology (CKDu) has emerged agricultural population. This study aimed to obtain a prevalence of cholinesterase activity and CKDu, and evaluate factors associated with organophosphate (OP) and carbamate (CA) poisoning and CKDu among farmers in Nakhon Ratchasima province, Thailand. A cross-sectional study was conducted among 58 farmers, with data collected using a structured questionnaire. Blood and urine samples were collected for analysis of erythrocyte acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), serum creatinine (SCr), and urinary creatinine (UCr). Farmers who had CKD without diabetes, hypertension, proteinurea, and other traditional causes were classified as CKDu. The average age (± SD) was 49.22(± 6.87) years. The prevalence of abnormal AChE and BuChE activity levels were 55.17% and 46.55%, respectively. In kidney function, the prevalence of abnormal UCr was 17.24% and CKDu was 24.14%. In adjusted model, the type of pesticide sprayer and personal protective equipment used were significantly associated with CKDu (bivariate analysis, p < 0.05). Using multivariate analysis, OP and CA poisoning were significantly associated with a 4.703-fold higher risk of CKDu (95% CI = 1.020-21.686). Farmers who applied OP and CA pesticides had decreased kidney function. These findings might be beneficial in reducing the adverse effects pesticide exposure and CKDu prevention.

Simultaneous determination of carbofuran and 3-hydroxycarbofuran in duck liver by an UPLC-MS/MS

AbstractCarbofuran is a carbamate pesticide, a broad-spectrum, high-efficiency, low-residue, and highly toxic insecticide, acaricide, and nematicide, widely used in agriculture. Carbofuran is most harmful to birds, and birds or insects killed by furan poisoning can be killed by secondary poisoning after being foraged by raptors, small mammals, or reptiles. In this paper, an UPLC-MS/MS method was developed for the determination of carbofuran and its metabolite, 3-hydroxycarbofuran, in duck liver. Liver tissue was first ground into a homogenate and then passed through ethyl acetate liquid-liquid extraction processing samples. Multiple reaction monitoring (MRM) mode was used for quantitative analysis, m/z 222.1 → 165.1 for carbofuran, m/z 238.1 → 180.9 for 3-hydroxycarbofuran and m/z 290.2 → 198.2 for an internal standard. The standard curves of carbofuran and 3-hydroxycarbofuran in duck liver were within a range of 2–2000 ng/g, where the linearity was good, the lower limit of quantification was 2 ng/g. The intra-day precision of carbofuran and 3-hydroxycarbofuran was &lt;14%, and the inter-day precision was &lt;13%, the accuracy range was between 91.8 and 108.9%, the average extraction efficiency was higher than 75.1% with a matrix effect between 93.4 and 107.7%. The developed method was applied to a situation of suspected duck poisoning at a local farm.

A novel acetylcholinesterase biosensor with dual-recognized strategy based on molecularly imprinted polymer

Biosensors using acetylcholinesterase (AChE) as the recognition element detect both toxicity (AChE inhibition activity) and concentration of organophosphorus pesticides (OPs). However, real application of these biosensors remains a challenge due to their low selectivity and low resistance to sample matrix, interferences and hash analytical conditions. In this study, a novel dual-recognized strategy was established by using molecularly imprinted polymer (MIP) and AChE selective to different moieties of acephate (AP) as affinity molecules simultaneously. Using AP as the model OP, MIP highly selective to certain moieties but not phosphorus of AP was prepared on the surface of microplate by self-polymerization of dopamine. The MIP enriched AP from samples selectively. Then AChE selective to phosphorus of AP quantified the levels of AP captured by MIP. AP captured by MIP still inhibited the activity of AChE because the affinity of AP to AChE was higher than to MIP. By incorporating selective sample pretreatment with AChE inhibition assay in one sensor, the biosensor identified AP from other OPs, carbamates pesticides and interferences commonly found in food and environmental samples. When vegetables with high matrix effect on AChE inhibition assay were analyzed, selective sample pretreatment ensured the biosensor to detect AP more accurately and selectively than classical AChE inhibition assay. The results of the biosensor had no statistical difference compared with those of HPLC-MS/MS. The dual-recognized strategy may provide a new solution to detect target enzyme inhibitors in complicated samples using enzyme-based biosensors selectively and accurately.

Simultaneous Determination of Seven Carbamate Pesticide Residues in Vegetable by Capillary Electrophoresis with Solid Phase Microextraction

Simultaneous Determination of Seven Carbamate Pesticide Residues in Vegetable by Capillary Electrophoresis with Solid Phase Microextraction

An old story with new insights into an ignored issue of metabolites in biochar-amended soil: Effect of biochar on dissipation of carbosulfan as an example

Carbofuran (CAS) is one of extensively used carbamate pesticides, which is considered as a derivative or a candidate of carbofuran (CAN) for its lower toxicity and persistence. Nevertheless, CAS could be degraded into its toxic metabolites, imposing potential risks on ecological safety. In this paper, biochars, derived from rice straw (RS), chicken manure (CM), corn straw (CS) and tire rubber (TR), were applied in CAS-contaminated soil to explore their effects on the dissipation of CAS and its metabolites. The dissipation rate of CAS was depressed by the amendment of biochar, mainly because biochar inhibited the hydrolysis of CAS by elevating soil pH value. Nevertheless, CS has efficiently enhanced the dissipation of CAN by almost 2-times for its promotion in hydrolysis and biodegradation. CS and CM improved biodegradation by altering the composition and structure of the microbial communities, exhibiting potential for facilitating bioremediation of CAS and CAN. Moreover, steam activated biochar accelerated the dissipation rate by 1.7–2.9 times and 1.3–2.4 times for CAS and CAN, respectively. This study investigated the effects of biochar on CAS and its toxic metabolites as well as possible governing mechanisms, providing rational instruction for biochar application in ambient atmosphere.