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Chlorpyrifos (CPF) is one of the most widely used organophosphorus pesticides all over the world. Unfortunately, long-term exposure to CPF may cause considerable toxicity to organisms. Some evidence suggests that the intestinal microbial community may be involved in regulating the toxicity of CPF. In this study, we explored if the intestinal microbial community is involved in regulating the toxicity of CPF. Adult mice were continuously exposed to CPF (4 mg/kg body weight /day) for 10 weeks with or without a 2-week pretreatment of antibiotics to change the ecological structure of intestinal microorganisms in advance. Pathological changes in the liver and kidneys were examined and the biochemical parameters in serum for liver and kidney functions were detected, and changes in the intestinal microbial community of the mice were measured. The results showed that subchronic exposure to low-dose CPF caused an ecological imbalance in the intestinal flora and caused pathological damage to the liver and kidneys. Serum biochemical indicators for liver function such as alanine aminotransferase and total bile acids contents and renal biochemical indicators such as urea nitrogen and creatinine were disrupted. Changes in intestinal microbial community structure by using antibiotics in advance can effectively alleviate the pathological and functional damage to the liver and kidneys caused by CPF exposure. Further analysis showed that intestinal microorganisms such as Saccharibacteria (TM7), Odoribacter, Enterococcus and AF12 genera may be involved in managing the toxicity of CPF. Together, our results indicated that long-term low-dose CPF exposure could induce hepatotoxicity and nephrotoxicity, and liver and kidney damage may be mitigated by altering the ecology of intestinal microorganisms. [ABSTRACT FROM AUTHOR]

The main objective of the present study was to investigate the toxicity of orally administered organophosphorus dimethoate pesticide in Rattus norvegicus on the basis of biochemical alterations in the blood. There was a total of eight groups: two control groups and six treatment groups. Albino rats of the exposed groups were fed simple laboratory chow along with a low dose: five milliliters were given to the T1 group; the medium dose, ten milliliters, was given to the T2 group; and the high dose, twenty milliliters, was given to the T3 group of dimethoate pesticide for thirty, sixty, or ninety days under controlled laboratory conditions. At the end of the experiment, any weight gain, changes in the blood parameters, or biochemical changes were determined. The results revealed increases in the total glucose, aspartate aminotransferase, and alanine aminotransferase levels in the exposed groups of both genders of albino rats. There were decreases in the levels of urea, uric acid and total bilirubin in the exposed groups of both genders of albino rats. These effects did not vary between the sexes. This study provides a foundation for further research on the long-term effects of dimethoate and similar pesticides, promoting the development of safer alternatives. [ABSTRACT FROM AUTHOR]

Introduction/purpose: Organophosphates are widely used nowadays. They have applications as pesticides, drugs, plasticizers, flame retardants, or chemical warfare agents. Their acute toxicity is ascribed to inhibiting acetylcholinesterase (AChE), a key enzyme in the transmission of nerve impulses in animals. Their toxic effects manifest by acetylcholine accumulation in the nerve synapses and can lead to paralysis or death. Organo-thiophosphate pesticides (OPs) are used in large quantities. Their oxo-analogs can also be found in the environment due to oxidation. Once accumulated in the environment, they exhibit toxic effects on non-target organisms. Methods: The hydrolysis of OPs in different pH was systematically analyzed, and their neurotoxic effects were evaluated. The concentration of the investigated pesticides during decomposition was monitored by ultraperformance liquid chromatography (UPLC). At the same time, a decrease in the toxicity of the treated samples was observed by measuring the activity of the enzyme AChE. Results: OPs decompose rapidly in alkaline aqueous solutions but are highly stable in acidic solutions. Chlorpyrifos hydrolyzes the fastest and dimethoate the slowest. The toxicity of these OP solutions decreases over time, indicating that more toxic products were not formed. Conclusion: The presented results can provide a sound basis for further efforts to find simple and efficient decomposition methods of OPs. [ABSTRACT FROM AUTHOR]

Organophosphorus pesticides are commonly employed in agricultural fields due to their potent insecticidal properties and short environmental persistence. However, organophosphorus pesticides enter the human body through the food chain, surface, and groundwater, leading to irreversible damage to the nervous system. Therefore, monitoring the presence of organophosphorus pesticides in food is necessary to ensure human safety. Herein, an ultra‐sensitive electrochemical biosensor has been prepared by using graphitic carbon nitride decorated molybdenum sulfide (g‐C3N4@MoS2) as a catalyst for the detection of organophosphorus pesticides, trichlorfon. The synergistic effect of g‐C3N4@MoS2 boosts the electron transfer across the electrode surface, further contributing to the immobilization of acetylcholinesterase (AChE) enzyme using glutaraldehyde as a crosslinking agent. At optimum conditions, the developed biosensor (AChE/g‐C3N4@MoS2/ITO) demonstrated a broad linear range (5–100 nM) with a low detection limit (LOD) of 2.1 nM obtained using the equation 3σ/S where σ is the standard deviation and S is the sensitivity of the bioelectrode. In addition, the AChE/g‐C3N4@MoS2/ITO biosensor exhibited good stability and reproducibility, with satisfactory results for real sample analysis of trichlorfon detection. [ABSTRACT FROM AUTHOR]

We report on the sensing of a hazardous pesticide alphacypermethrin (ACM) using electrochemical technique through a nanocomposite film modified electrode. The nanocomposite film comprising of octadecylamine, chitosan, polyvinyl alcohol-silver nanowires and haemoglobin, shortly (OCPAH), was prepared by Langmuir–Blodgett (LB) film deposition technique on various substrates and electrodes. The composite LB film was characterised by UV-visible spectroscopy and scanning electron microscopy, which confirms the stable and multilayer film. The LB film modified electrode was used for sensing ACM pesticide by cyclic voltammetry (CV), differential pulse voltammetry (DPV), and square wave voltammetry (SWV) techniques. The achieved sensing parameters such as limit of detection as 14 nM, 5 nM and 10 nM; linear range as 10–100 nM, 10–40 nM and 50–100 nM/10–100 nM; and sensitivity as 0.418 µA/nM/cm2, 0.259 µA/nM/cm2 and 0.271 µA/nM/cm2 for CV, DPV and SWV techniques, respectively. The reported sensor is found to have stability of 74% upto 20 cycles, the relative standard deviation (RSD) value for metal ion/organic interference species as 2% and for real samples are within 1.4% using CV technique. The reported nanocomposite-based ACM pesticide sensor will open up new options for research on LB film nanocomposite-based sensing of different organophosphorus groups of pesticides. [ABSTRACT FROM AUTHOR]

BACKGROUND: Several studies have addressed the adsorption of pesticides such as alachlor, acetochlor, metolachlor and fenthion from water and wastewater, yet the interaction of these compounds with natural organic matter (NOM) complicates their effective removal owing to competitive adsorption effects. This study aims to fill this gap by exploring the efficacy of nitric acid and chlorosulfonic acid‐modified activated carbons (ACs) in removing both pesticides and NOM under realistic environmental conditions. RESULTS: Modifications using nitric acid and chlorosulfonic acid significantly improved the pesticide removal capabilities of Norit SX F Cat (AC1) adsorbents. While both the original and chlorosulfonic acid‐modified adsorbents showed comparable efficacy in pesticide removal, nitric acid‐modified AC Puriss (AC2) adsorbents were less effective. Remarkably, a 100 mg L−1 dose of both original and modified powdered ACs (PACs) removed >98% of all four pesticides from water samples. Additionally, a lower 25 mg L−1 dose effectively achieved similar removal rates, demonstrating their utility as feasible options for water treatment. CONCLUSION: Modifying PACs with nitric acid and chlorosulfonic acid has been proven to enhance their structural and adsorptive properties significantly. These modifications led to improved pesticide removal efficiencies, particularly with the chlorosulfonic acid‐modified PACs, which demonstrated superior performance in adsorption tests. The study also highlighted the competitive adsorption posed by low‐molecular‐weight organic substances in water, which compete with pesticides for active adsorption sites. © 2024 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Background: Pesticide poisoning kills hundreds of thousands of people in the Asia Pacific region each year. The majority are from deliberate self-poisoning with organophosphorus pesticides (OP), paraquat etc. It is a critical health problem in rural areas, where hazardous pesticides are easily available. Very few studies were present regarding this in India and research on anti-dotes to commonly available pesticides is very minimal. According to WHO report, it is the 2nd most common cause of death among people aged 15-29 years. Methodology: An observational study was conducted to study suicidal poisoning cases from Jan-June 2022 in a retrospective record-based manner. Qualitative variables were represented with graphs and tables. Quantitative variables were represented with mean and Standard deviation. Multinomial logistic regression was done to test the significance of poisoning agents with survival status. Nagelkerke R-squared mean regression model was considered in the analysis. p-value less than 0.05 was considered significant. Results: The incidence of suicidal poisoning was 696(~0.46%) during the study period. The mean age of the study population is 32.5±12.3 years. Majority of the cases were Organophosphorus compounds and paraquat comprising a total of about 26.11%. Fatality rate was 17.4% Multinomial logistic regression of various poisoning agents showed high significance of mortality OP poisoning (p=0.03), Paraquat poisoning (p<0.001) and Herbicides (p=0.02). Conclusion: Young populations were more prone to commit suicide suggesting increased recognition of the need for a coordinated response involving public health officials and psychiatric specialists to conduct mental health awareness camps and to provide counselling. Strengthening of translational research to develop anti-dotes for commonly available pesticides. [ABSTRACT FROM AUTHOR]

MPs have raised significant public concern due to their role as carriers of organic contaminants in aqueous solutions. DZN is a non-systemic organophosphorus pesticide that poses risks to human and environmental health. This study aimed to investigate the adsorption of DZN onto PE MPs by examining factors such as PE dose, reaction time, pesticide concentration, and pH through experimental runs based on the Box‒Behnken model. According to the Langmuir model, the maximum adsorption capacity of PE for DZN was 0.35 mg/g. The results indicated that the highest adsorption rate of DZN (92%) was observed in distilled water, while the lowest adsorption rate (57%) was observed in municipal wastewater. The ΔH° and ΔS° values were obtained as − 0.16 kJ/mol and 54.41 J/(mol K), respectively. Therefore, regarding negative ΔG° values, it can be concluded that the adsorption of DZN onto PE MPs is an exothermic, highly disordered, and spontaneous process. The findings indicate a reduction in the adsorption rate of DZN as the concentrations of interfering compounds increase. These findings offer understanding of the interaction between MPs and organic contaminants, emphasizing the need for further studies and approaches to reduce their harmful impact on human health and the environment. [ABSTRACT FROM AUTHOR]

The identification and detection of pesticides is crucial to protecting both the environment and human health. However, it can be challenging to conveniently and rapidly differentiate between different types of pesticides. We developed a supramolecular fluorescent sensor array, in which calixarenes with broad-spectrum encapsulation capacity served as recognition receptors. The sensor array exhibits distinct fluorescence change patterns for seven tested pesticides, encompassing herbicides, insecticides, and fungicides. With a reaction time of just three minutes, the sensor array proves to be a rapid and efficient tool for the discrimination of pesticides. Furthermore, this supramolecular sensing approach can be easily extended to enable real-time and on-site visual detection of varying concentrations of imazalil using a smartphone with a color scanning application. This work not only provides a simple and effective method for pesticide identification and quantification, but also offers a versatile and advantageous platform for the recognition of other analytes in relevant fields. [ABSTRACT FROM AUTHOR]

In this study, the degradation system of Shewanella oneidensis MR-1 and goethite was constructed with chlorpyrifos as the target contaminant. The effects of initial pH, contaminant concentration, and temperature on the removal rate of chlorpyrifos during the degradation process were investigated. The experimental conditions were optimized by response surface methodology with a Box–Behnken design (BBD). The results show that the removal rate of chlorpyrifos is 75.71% at pH = 6.86, an initial concentration of 19.18 mg·L−1, and a temperature of 30.71 °C. LC-MS/MS analyses showed that the degradation products were C4H11O3PS, C7H7Cl3NO4P, C9H11Cl2NO3PS, C7H7Cl3NO3PS, C9H11Cl3NO4P, C4H11O2PS, and C5H2Cl3NO. Presumably, the degradation pathways involved are: enzymatic degradation, hydrolysis, dealkylation, desulfur hydrolysis, and dechlorination. The findings of this study demonstrate the efficacy of the goethite/S. oneidensis MR-1 complex system in the removal of chlorpyrifos from water. Consequently, this research contributes to the establishment of a theoretical framework for the microbial remediation of organophosphorus pesticides in aqueous environments. [ABSTRACT FROM AUTHOR]

Modern agriculture is mainly based on the use of pesticides to protect crops but their efficiency is very low, in fact, most of them reach water or soil ecosystems causing pollution and health hazards to non-target organisms. Fungicide triazoles and strobilurins based are the most widely used and require a specific effort to investigate toxicological effects on non-target species. This study evaluates the toxic effects of four commercial fungicides Prosaro® (tebuconazole and prothioconazole), Amistar®Xtra (azoxystrobin and cyproconazole), Mirador® (azoxystrobin) and Icarus® (Tebuconazole) on Eisenia fetida using several biomarkers: lipid peroxidation (LPO), catalase activity (CAT), glutathione S-transferase (GST), total glutathione (GSHt), DNA fragmentation (comet assay) and lysozyme activity tested for the first time in E. fetida. The exposure to Mirador® and AmistarXtra® caused an imbalance of ROS species, leading to the inhibition of the immune system. AmistarXtra® and Prosaro®, composed of two active ingredients, induced significant DNA alteration, indicating genotoxic effects. This study broadened our knowledge of the effects of pesticide product formulations on earthworms and showed the need for improvement in the evaluation of toxicological risk deriving from the changing of physicochemical and toxicological properties that occur when a commercial formulation contains more than one active ingredient and several unknown co-formulants. [ABSTRACT FROM AUTHOR]

In the present work, graphitic carbon nitride/GO/V2O5 nanocomposite was synthesized via a single stage and utilized this photocatalyst for the degradation of the pesticide Chlorpyrifos. The nanocomposite was prepared using the hydrothermal method. The crystal structure was determined using powder X-ray diffraction of ternary nanocomposite material crystallite size, phase, and defects. Scanning electron microscopy (SEM) and FT-IR evaluated surface morphologies and functional groups. FTIR heterocycle C–N and C=N stretching modes due to bands of 1200–1650 cm−1 During the course of the experiment, the impacts of the experimental parameters (such as pH, time, H2O2 concentration, and Catalyst Dose) on the degradation of Chlorpyrifos were investigated. The photocatalytic studies indicated that the graphitic carbon nitride/GO/V2O5 composites significantly outperformed the pure versions of g-C3N4 in photocatalytic degradation of Chlorpyrifos. The excellent photocatalytic removal efficiency of more than 88% in 120 min obtained using a graphitic carbon nitride/GO/V2O5 catalyst pointed toward a great alternative catalyst for the treatment of Chlorpyrifos and other hazardous pesticides from wastewater. By using 0.1% H2O2, the photocatalytic elimination of Chlorpyrifos was further increased from 88 to 90.5%. The g-C3N4/GO/V2O5 catalyst has outstanding recycling performance and a high level of stability. [ABSTRACT FROM AUTHOR]

Background: The large-scale application of pyrethroids and organophosphorus pesticides has great benefits for pest control. However, the increase of cancer incidence rate in recent years has also caused public concern about the health risks of pesticides. Hence, we utilized data from the National Health and Nutrition Examination Survey (NHANES) to assess the association and risk between pesticide exposure and several cancers, along with the comprehensive impact of oxidative stress. In this study, six cancers and six common pesticides were included to analyze their correlation and risk. And the levels of eight oxidative stress marks and two inflammatory markers were used for stratified analysis. Multiple logistic regression analysis was applied to estimate the odds ratio and 95% confidence intervals. Machine learning prediction models were established to evaluate the importance of different exposure factors. Results: According to the data analyzed, each pesticide increased the risk of three to four out of six cancers on average. Iron, aspartate aminotransferase (AST), and gamma glutamyl transferase levels positively correlated with cancer risk in most cases of pesticide exposure. Except for demographic factors, factors such as AST, iron, and 3-phenoxybenzoic acid showed high contributions to the random forest model, which was consistent with our expectations. The receiver operating characteristic curve showed that the prediction model had sufficient accuracy (74.2%). Conclusion: Our results indicated that specific pesticide exposure increased the risk of cancer, which may be mediated by various oxidative stress mechanisms. Additionally, some biochemical indicators have the potential to be screened for cancer prevention. [ABSTRACT FROM AUTHOR]

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The rapid development of aptamers has helped address the challenges presented by the wide existed pesticides contaminations. Screening of aptamers with excellent performance is a prerequisite for successfully constructing biosensors, while further tailoring of aptamers with enhanced activity greatly improved the assay performance. Firstly, this paper reviewed the advanced screening strategies for pesticides aptamers, including immobilization screening that preserves the native structures of targets, non-immobilized screening based on nanomaterials, capillary electrophoresis-systematic evolution of ligands by exponential enrichment (CE-SELEX), virtual screening in silico, high-throughput selection, and rational secondary library generation methods, which contributed significantly to improve the success rate of screening, reduce the screening time, and ensure aptamer binding affinity. Secondly, the precise tailoring strategies for pesticides aptamers were modularly elaborated, containing deletion, splitting, elongation, and fusion, which provided various advantages like cost-efficiency, enhanced binding affinity, and new derived functional motifs. Thirdly, the developed aptamer-based biosensors (aptasensors) for pesticide detection were systematically reviewed according to the different signal output modes. Finally, the challenges and future perspectives of pesticide detection are discussed comprehensively. [ABSTRACT FROM AUTHOR]

Pesticides are the ubiquitous xenobiotics. Ethion, an organophosphorus pesticide, induces adverse effects in animals upon ingestion. Quercetin, a potent antioxidant, has very low water solubility. As a result, this study aimed to synthesize and analyze nanoparticles of quercetin and assess their potential to mitigate oxidative harm caused by ethion in rats. Ethion was administered at dose rates of 3.6 and 7.2 mg/kg once daily for 90 days. Quercetin (50 mg/kg) and quercetin nanoparticles (50 mg/kg) were also simultaneously administered to high-dose ethion-administered rats in separate groups for 90 days. A 10% blood hemolysate was prepared and analyzed for different biochemical parameters. Groups subjected to ethion treatment exhibited a notable increase in lipid peroxidation, indicated by heightened MDA production, alongside a significant reduction in SOD levels, Catalase, GSH, GPX, GST, and GR. In groups treated with quercetin and quercetin nanoparticles, the impact of ethion-induced oxidative stress was notably mitigated, particularly in the quercetin nanoparticles-treated group. [ABSTRACT FROM AUTHOR]

Background: Pesticide bans and regulatory restrictions have been shown to be effective strategies for preventing suicide in several countries. Suicide and suicide by pesticides have decreased significantly in China over the past two decades. However, whether the reduction was associated with pesticide regulation is unknown. Methods: The monthly data on suicide and suicide by pesticide from 2006 to 2018 were obtained from China's Disease Surveillance Point (DSP) system. Information on China's pesticide regulations since 1970 was obtained from Pesticide Action Network International (PAN International), Joint Meeting on Pesticide Management Highly Hazardous Pesticides (JMPM HHP) lists, the website of the Ministry of Agriculture of China, Pesticide Information Network of China, and the Wan Fang database. Change point detection and policy analysis were combined to identify the time of any trend change breakpoint of suicide and suicide by pesticide. Interrupted time series analysis was used to investigate the pre- and post-breakpoint trends of monthly standardized rates in suicide and suicide by pesticide. Results: The standardized pesticide suicide rate decreased by 60.5% from 6.50 in 2006 to 2.56 per 100,000 in 2018. Larger declines were evident among people in urban areas (67.3%), female individuals (63.5%), and people aged 15-44 years (68.1%). The effect of policies banning highly hazardous organophosphorus pesticides (HHOP) [rate ratio (RR) = 0.993, 95% CIs (0.991--0.994)] in December 2008 and stopping domestic sales and use of paraquat aqueous solution (RR = 0.992, 95% CIs: 0.990-0.994) in July 2016 were more pronounced than regulating the paraquat-related products (RR = 1.003, 95% CIs: 1.002-1.004) in April 2012. Conclusion: Declines in suicide by pesticide in China occurred contemporaneously with regulatory bans and restrictions implemented on several pesticides, particularly in urban areas, among female individuals, and the relatively low age profile. These findings indicate the potential influence of these bans on trends of suicide by pesticides. [ABSTRACT FROM AUTHOR]

Highlights: What are the main findings? Abnormally increased concentrations of ingested or inhaled pollutants can lead to cardiac oxidative stress and inflammation. Untreated cardiac inflammation promotes myocardial fibrosis and cardiac arrhythmias. What is the implication of the main findings? Patients hospitalized for acute pesticide poisoning often suffer from episodes of atrial or ventricular fibrillation. Management of pollutant poisoning associated with AF includes detoxification (i.e., gastric lavage) and prompt rhythm control. Atrial fibrillation (AF) is the most common type of cardiac rhythm disorder. Recent clinical and experimental studies reveal that environmental pollutants, including organophosphorus–organochloride pesticides and air pollution, may contribute to the development of cardiac arrhythmias including AF. Here, we discussed the unifying cascade of events that may explain the role of pollutant exposure in the development of AF. Following ingestion and inhalation of pollution-promoting toxic compounds, damage-associated molecular pattern (DAMP) stimuli activate the inflammatory response and oxidative stress that may negatively affect the respiratory, cognitive, digestive, and cardiac systems. Although the detailed mechanisms underlying the association between pollutant exposure and the incidence of AF are not completely elucidated, some clinical reports and fundamental research data support the idea that pollutant poisoning can provoke perturbed ion channel function, myocardial electrical abnormalities, decreased action potential duration, slowed conduction, contractile dysfunction, cardiac fibrosis, and arrhythmias including AF. [ABSTRACT FROM AUTHOR]

The aim of the current study was to investigate endosulfan effects on the Acetylcholinesterase (AChE) enzyme and gene in albino mice. Thirty selected male albino mice were randomly divided into 3 groups. The first group was control group (G1), while the other two treated groups were injected intraperitoneally twice per week with two doses of endosulfanG2 (3 mg/kg) and G3 (17 mg/kg) for 21 and 45 days respectively. The results recorded a significant decrease in AChE enzyme in the group treated with 17 mg/kg b.wt. (3986.67 ±170.32 U/L),compared to the control (5584.33 ±140.35 U/L)and treatment group with 3 mg/kg b.wt.(5556.00 ±341.01) U/L for 21 days. Also, there was a significant decrease in the enzyme level between the two treated groups (4688.00 ±221.49 U/L)and (3413.67 ±305.42 U/L) for the duration of 45 days of the dose, compared with the control group (5584.33 ±140.35 U/L), and increased expression of AChE gene in the treated groups. Gene expression fold in all treated groups was higher than in the control group with the highest recorded value of 14.320at 17 mg/kg for 45 days, compared with the control group. [ABSTRACT FROM AUTHOR]

Organophosphates (OPs) and carbamates (CMs) are two classes of pesticides that are widely used in agriculture, public health, and home pest control. Both OPs and CMs work by inhibiting the activity of acetylcholinesterase, an enzyme that breaks down the neurotransmitter acetylcholine. Analytical methods used for the detection of OPs and CMs can be costly, as they often require specialized equipment and experienced analysts. Therefore, it is necessary to develop low-cost, quick, and simple analytical techniques for OPs and CMs detection. This study developed a method for detecting OPs and CMs using esterase enzymes from honey bee heads and a colorimetric technique. The limits of detection (LODs) for OPs include dicrovos, mevinphos, azinophos-methyl, and chlorpyrifos with values of 0.005, 0.001, 0.02, and 0.02 mg/kg, respectively, and the LODs for CMs are carbaryl, ethiofencarb, oxamyl, and fenobucarb with values of 0.0008, 0.03, 0.01, and 0.09 mg/kg, respectively. Comparisons between the developed method and the GC-FPD showed no difference in detecting OPs and CMs residues in fruits and vegetables. This developed method can detect OPs and CMs residues in fruits and vegetables, which will help reduce costs and facilitate easy verification. [ABSTRACT FROM AUTHOR]

Simple Summary: We used the geometric morphometrics method to explore whether the exposure of the parental females to pirimiphos-methyl at short exposure times may impact the wings of the F1 generation of Rhyzopertha dominica, Prostephanus truncatus, and Tenebrio molitor. For this purpose, adult females of the three coleopterans were exposed to treated concrete at the label dose for 30 min, 3, 5, 8, 16, 24, and 36 h. Their offspring responded differently to pirimiphos-methyl. The most noticeable deformations were observed in the elytra and hindwings of T. molitor, and males experienced deeper morphological changes than females. The hindwings of P. truncatus exhibited morphological deformations after 36 h of exposure to pirimiphos-methyl. Rhyzopertha dominica proved the least susceptible species since pirimiphos-methyl did not have any effect on both elytra and hindwings. Tenebrio molitor L. (Coleoptera: Tenebrionidae), Prostephanus truncatus (Horn), and Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae) are noxious insect pests of grains in storages. Pirimiphos-methyl is widely used to protect grains at the post-harvest stage. However, the sub-lethal impact of this active ingredient on the offspring of all three coleopterans remains unknown. Thus, mated females of each species were exposed separately to pirimiphos-methyl at short exposures (30 min, 3, 5, 8, 16, 24, and 36 h), where the elytra and hindwings of the adult progeny were analyzed with the geometric morphometrics method. Males and females of all species were incorporated into the analysis. The results revealed variability among species. Tenebrio molitor was the most sensitive among three species, displaying significant deformations in the elytra and hindwings. Males had more conspicuous morphological changes than females. Prostephanus truncatus hindwings exhibited deformities after 36 h of exposure to pirimiphos-methyl. In contrast, R. dominica offspring were not affected by pirimiphos-methyl. In light of our findings, organophosphorus insecticides may cause variable sub-lethal effects to stored-product insects. This issue may lead to different insecticidal treatments according to the targeted stored-product species. [ABSTRACT FROM AUTHOR]

Pesticides are considered to be toxic pollutants that are harmful to the health of humans and animals or dangerous to the environment. The pesticides chlorpyrifos, acetochlor, and dicofol, representatives of organophosphorus, acyl amide, and organochlorine pesticides, are widely used in agriculture and have been frequently detected in aquatic environments. However, the toxicity of these pesticides to marine microbes is unclear. In this study, the toxic effects of the three pesticides on a representative marine microalga, the diatom Skeletonema costatum (S. costatum), were investigated. Microalgal cell density and chlorophyll-a (Chl-a) content were analyzed to investigate the toxic effects after S. costatum was exposed to the three pesticides both individually and in combination. The N/P ratio in the culture medium and the degradation of the pesticides were also analyzed during exposure. Individual acute toxicity analysis indicated that the growth of S. costatum was significantly inhibited by acetochlor, followed by the effect of dicofol and chlorpyrifos. The cell membrane of the microalgae was impaired by acetochlor. Combined toxicity analysis indicated that the presence of acetochlor increased the toxicity of dicofol and chlorpyrifos. In contrast, the presence of dicofol reduced the toxicity of acetochlor and chlorpyrifos. The N/P ratio in the culture medium was largely increased at late growth stages; however, it was significantly lowered when the microalgae were exposed to chlorpyrifos compared to acetochlor and dicofol. The degradation of the pesticides was promoted by microalgae, suggesting that microalgae might contribute to the removal of these pesticides from the marine environment. The toxic mechanism of the pesticides on the marine microalgae and the fates of pesticides in the ocean need to be further studied. [ABSTRACT FROM AUTHOR]

Pesticides have been widely used to ensure the yield and quality of crops in modern agriculture, such as insecticides, herbicides, fungicides, and plant growth regulators. Among them, chlorpyrifos can be one of the best-selling organophosphorus pesticides in the world. However, the irrational use of chlorpyrifos can lead to excessive pesticide residues in food products, event harm to human health. The persistence and toxicity of chlorpyrifos have received ever-increasing attention in recent years. Furthermore, chlorpyrifos can be restricted or banned in a few countries, due to the residue risks. Therefore, the high-enrichment factor needle filter solid-phase microextraction and a highly sensitive enzyme inhibition-digital image colorimetry have been used for the rapid detection of chlorpyrifos residues in food samples, in order to avoid the traditional cumbersome steps and low sensitivity. However, there are still some challenges in both the pre-treatment and detection. In the pre-treatment process, the carbon materials as the solid phase adsorbents were added to a needle filter, and then the enrichment of chlorpyrifos in the food samples was achieved to repeat pumping of the needle filter by a syringe. The needle filter solid phase microextraction has the advantages of less adsorbent, less solvent, shorter time, and larger enrichment factors, compared with traditional solid phase extraction. The carbon material type and sample volume were optimized to achieve better recovery. In the detection, the tyrosinase can be used to oxidize the aminophenol and ferric chloride system into the yellow color. But chlorpyrifos can inhibit the activity of tyrosinase, even indirectly affect the color of the aminophenol and ferric chloride system. Particularly, digital image colorimetry can be used to analyze the color data after capturing the picture with a smartphone. The linear relationship can be quantitatively analyzed between chlorpyrifos concentration and green intensity. In this study, a highly efficient tyrosinase was selected, instead of acetylcholinesterase in the traditional enzyme inhibition. Digital image colorimetry was achieved in the qualitative and quantitative analysis, compared with traditional colorimetry. A better sensitivity was obtained to optimize the aminophenol concentration, tyrosinase concentration, reaction time, and incubation time. The results showed that the better linearity of chlorpyrifos was in the range of 0.005-0.1 mg/L with the determination coefficient (R²) ≥ 0.99. The limit of detection using a signal-to-noise ratio of 3 was 0.001 5 mg/L in mineral water, tea, and fruit juice. The limit of quantification using a signal-to-noise ratio of 10 was 0.005 mg/L in the mineral water, tea, and fruit juice. The spiked recoveries in the samples were 86.6%-92.5% with a relative standard deviation of 3.2%-6.9%, indicating higher accuracy and precision. The further application can be expected in real sample analysis. Consequently, the developed pre-treatment can be applied to extract different hydrophobic pesticides in food samples, together with the different organophosphorus and carbamate pesticides, indicating better inhibitory effects on tyrosinase. In conclusion, the finding can provide a strong reference to develop rapid pretreatment and detection techniques for pesticides. [ABSTRACT FROM AUTHOR]

In present study, a new sample pretreatment method based on the combination of stirring-assisted ferrofluid-based liquid phase microextraction and dispersive liquid–liquid microextraction has been developed for the extraction of some pesticides (diazinon, deltamethrin, fenpropathrin, phosalone, prometryn, simazine, and terbutryn) from herbal distillate samples. In this method, a few microlitre of a synthesised ferrofluid as an extraction solvent is added into the sample solution containing the analytes and the mixture is stirred at a high rate to increase the contact area between the ferrofluid and sample solution. Then the stirring procedure is stopped and the ferrofluid droplets containing the analytes are collected on the surface of stir bar. In the next step, the stir bar is washed with acetonitrile. In the following, the obtained mixture of acetonitrile and ferrofluid is rapidly injected into deionised water. The ferrofluid droplets are settled down at the bottom of a conical test tube and after back-extraction of the analytes into n-hexane, an aliquot of the extractant phase is injected into gas chromatography–mass spectrometry. Under optimum conditions, the introduced method offered high enrichment factors (1643−1884) and extraction recoveries (82–94%), low limits of detection (3.1–7.3 ng L–1) and quantification (10.3–24.3 ng L–1), and an acceptable repeatability (relative standard deviation ≤ 7.9%). [ABSTRACT FROM AUTHOR]

Pesticide residue is an increasing concern in rotational crop practices. The pesticide used for the primary crop may re-enter the secondary crop, thus exceeding pesticide levels set by the positive list system (PLS). As such, evaluation of pesticide residue translocated into rotational crops is required for ensuring pesticide safety. In this study, we investigated the residue pattern of diazinon translocated into lettuce as a typical rotational crop in Korea. Diazinon was used to treat greenhouse soil at the maximum annual application rate before crop planting. Diazinon residues in soil and lettuce were investigated using liquid chromatography/tandem mass spectroscopy and a modified quick, easy, cheap, effective, rugged, safe (QuEChERS) method. The limit of quantitation (LOQ) of diazinon was found as 0.005 mg/kg for the plant and soil samples. The recovery of diazinon at the LOQ and 10× the LOQ ranged from 100.2% to 108.7%. The matrix calibration curve showed linearity, with R2 values > 0.998. Diazinon residue in soil dissipated over time after the initial treatment, generating first-order kinetics (R2 = 0.9534) and having a half-life of about 22 days. The uptake ratio (UTR) of diazinon from the soil to the plant ranged from 0.002 to 0.026 over the harvest period. Considering the UTRs, diazinon residue in the edible leaf could exceed the PLS level (0.01 mg/kg) if lettuce is rotated in soil containing >0.357 mg/kg of diazinon. Based on our findings, to comply with the PLS, a 3-month plant-back interval is required following diazinon treatment and/or setting the maximum residue limit of diazinon for lettuce. [ABSTRACT FROM AUTHOR]

Diazinon, an organophosphorus pesticide, widely used in agricultural activities, can be effectively degraded in aqueous solutions via advanced oxidation processes. Electrochemical oxidation is a promising technique for the degradation of recalcitrant organic micropollutants in water. Thus, this study evaluated the pesticide diazinon degradation by anodic oxidation. To carry out the experiments, a synthetic solution of diazinon was used, with an initial concentration of 40 mg L−1. Two types of electrodes were evaluated, a dimensionally stable anode type, with RuO2–IrO2 composition, and a boron-doped diamond (BDD) electrode. In addition, two supporting electrolytes (NaCl and Na2SO4), the electrolyte concentration, current density and also energy consumption were evaluated. All configurations were able to promote the degradation of total organic carbon. The anodic oxidation for the degradation of diazinon was more efficient with the BDD electrode, reaching 97.5% of diazinon removal after 180 min with 25 mM of Na2SO4, a current density of 42 mA cm−2 and pH 3. [ABSTRACT FROM AUTHOR]

• A new method for the analysis of pesticides in soil using direct-immersion solid-phase microextraction (DI-SPME) is presented. • Extraction is performed by making an aqueous slurry and then extracting with constant stirring. • A plackett-burman screening was performed for ten variables. Extraction time and percentage of organic modifier on the slurry were the most crucial variables to optimize separately. • The method appears fit-for-purpose, with detection limits between 0.01–10 µ g/kg and adequate repeatability when using an isotopically labelled internal standard. A new method was evaluated and developed for the analysis of pesticides in sandy-loam soil by direct-immersion solid phase microextraction (DI-SPME) followed by gas chromatography tandem-mass spectrometry (GC–MS/MS) determination. Ten pesticides were selected based on a literature survey of the compounds reported to be present in EU soils. The extraction was performed using SPME LC-Tips, a new SPME configuration with the coated fibers attached to a disposable and easy-to-handle micropipette tip, which was immersed into a soil slurry made by the addition of an aqueous solution to the soil sample. Ten experimental parameters were evaluated with a Plackett-Burman design, after which the extraction time and percentage of organic solvent in the aqueous extraction were optimized separately. The two fiber chemistries available (PDMS/DVB and C 18) were evaluated in parallel for the entire work. In the final method, slurry samples were made by adding an aqueous solution (6 % methanol v/v) to 2 g of soil. The fiber was conditioned and then inserted, for extraction, into the samples, stirred by a magnetic bar. Afterwards, the analytes were desorbed onto 100 µ L of methanol. After the addition of analyte protectants (ethylglycerol, gulonolactone, and sorbitol) the extract was injected into the GC–MS/MS system. Isotopically labelled penconazole was used as internal standard. A calibration was performed by extracting spiked soil with analyte concentrations of 0.1–50 µg/kg. Coefficients of determination of the linear calibration were between 0.94–0.98 for the PDMS/DVB and 0.92–0.99 for the C 18. Limits of detection range between 0.01–10 µg/kg for the PDMS/DVB and 0.1–10 µg/kg for the C 18. Overall, the C 18 analytically outperformed the PDMS/DVB but required a longer extraction time (120 min vs 75 min for the PDMS/DVB). This method allows automation and generates low residual toxic waste, having the potential to be introduced as a greener and simpler alternative to currently used sample preparation methodologies. [ABSTRACT FROM AUTHOR]

A combination of modified quick easy cheap effective rugged and safe extraction approach with carbon nano–onions–based dispersive solid‐phase extraction and dispersive liquid–liquid microextraction was developed for the extraction of several pesticides (diazinon, chlorpyrifos, tebuconazole, deltamethrin, permethrin, haloxyfop–methyl, penconazole, and cyhalothrin) from grape before their analysis by gas chromatography–flame ionization detection. In the extraction approach, an aliquot of grape sample is chopped and after separating its juice, the pesticides that remained in the refuse are extracted by the quick, easy, cheap, effective, rugged, and safe extraction method. The obtained acetonitrile phase is mixed with juice and the analytes are extracted by the carbon nano‐onions‐based dispersive solid‐phase extraction. The analytes are concentrated using the microextraction procedure to obtain high enrichment factors. The results showed low limits of detection (0.5–1.6 ng/g) and quantification (1.8–5.4 ng/g) with satisfactory linearity of the calibration curves (determination coefficient, r2 ≥ 0.994). The precision of the developed method expressed as relative standard deviations was good (≤7.2%). The method provided high enrichment factors (350–410) and extraction recoveries (70–82%). Finally, seven grape samples were analyzed successfully. [ABSTRACT FROM AUTHOR]

This survey reports the monitoring of multi-pesticide residues of some fruits and vegetables sold in the local markets, sampled in 2018–2019, in the Souss Massa region in Morocco. A QuEChERS-LC-MS/MS method for 202 pesticides, belonging to different classes (carbamates, organophosphorus and organonitrogen pesticides) was applied and 51 samples were randomly bought from the local market, belonging to different products (tomato, cucumber, coriander, apricot, parsley, potato, zucchini, green bean, lettuce, strawberry and orange) and analysed for pesticide residues, which were detected in 69% of the samples, below the maximum residue limits (MRLs) for some pesticides which represent 14% of the targeted compounds. The most frequently detected compounds were acetamiprid, acibenzolar-s-methyl, abamectin, azoxystrobin, bifenazate, bitertanol, bromuconazole, butoxycarboxim, cyromazine, difenoconazole, epoxiconazole, fenbuconazole, fluometuron, linuron, metaflumizone, metconazole, metribuzin, myclobutanil, pirimicarb, pyraclostrobin, propamocarb, rotenone, trichlorfon, tebuconazole, tetraconazole, thiamethoxam and thiophanate-methyl. The obtained results provide a value to the situation of pesticide residues in Morocco. [ABSTRACT FROM AUTHOR]

As in the case of the food industry in general, there is a global concern about safety and quality in complex food matrices, such as honey, which is driving the demand for fast, sensitive and affordable analytical techniques across the honey-packaging industry. Although excellent techniques such as liquid chromatography-tandem mass spectrometry (LC-MS/MS) are available, these are located in centralized laboratories and are still lacking in speed, simplicity and cost-effectiveness. Here, a new approach is presented where a competitive immunoassay is combined with a novel High Fundamental Frequency Quartz Crystal Microbalance with Dissipation (HFF-QCMD) array biosensor for the simultaneous detection of antibiotics and pesticides in honey. Concretely, thiabendazole and sulfathiazole residues were monitored in spiked honey samples. Results revealed that HFF-QCMD arrays provide a complementary and reliable tool to LC-MS/MS for the analysis of contaminants in these kinds of complex matrices, while avoiding elaborate sample pre-treatment. The good sensitivity achieved (I50 values in the 70–720 µg/kg range) and the short analysis time (60 min for 24 individual assays), together with the ability for multiple analyte detection (24 sensor array) and its cost-effectiveness, pave the way for the implementation of a fast on-line, in situ routine control of potentially hazardous chemical residues in honey. [ABSTRACT FROM AUTHOR]

Novel, sensitive, selective, efficient and portable electrochemical biosensors are needed to detect residual contaminants of the pesticide 1-naphthyl methylcarbamate (carbaryl) in the environment, food, and essential biological fluids. In this work, a study of nanocomposite-based Ag reduced graphene oxide (rGO) and chitosan (CS) that optimise surface conditions for immobilisation of acetylcholinesterase (AChE) enzyme to improve the performance of catalytic biosensors is examined. The Ag/rGO/CS nanocomposite membrane was used to determine carbaryl pesticide using a potentiometer transducer. The AChE enzyme-based biosensor exhibits a good affinity for acetylthiocholine chloride (ATCl). It can catalyse the hydrolysis of ATCl with a potential value of 197.06 mV, which is then oxidised to produce a detectable and rapid response. Under optimal conditions, the biosensor detected carbaryl pesticide at concentrations in the linear range of 1.0 × 10−8 to 1.0 μg mL−1 with a limit of detection (LoD) of 1.0 × 10−9 μg mL−1. The developed biosensor exhibits a wide working concentration range, detection at low concentrations, high sensitivity, acceptable stability, reproducibility and simple fabrication, thus providing a promising tool for pesticide residue analysis. [ABSTRACT FROM AUTHOR]

Organophosphate hydrolase (OphB) gene from Pseudomonas sp. was transferred into Arabidopsis plants to observe the bioremediation ability and tolerance level of the transgenic plant to organophosphate pesticides contaminants. Gene transfer was observed by PCR of the transgenic Arabidopsis plants' genomic DNA. Expression of ophB gene and protein levels in the transgenic Arabidopsis plants was observed by western blot analysis. The transgenic plants were resistant and tolerant to chlorpyrifos (an organophosphate pesticide), as evidenced by a toxicity test, where the transgenic plants produced greater shoot and root biomass than that of wild type plants. The fresh weight of transgenic Arabidopsis plants' did not reduced significantly till 400 ppm chlorpyrifos treatment, but fresh weight of wild type Arabidopsis plants' significantly reduced by the application of 100 ppm chlorpyrifos. Moreover, in 600 ppm chlorpyrifos liquid culture, transgenic Arabidopsis plants' produced 1.34 g biomass from 100 seeds, but wild type Arabidopsis plants' produced only 0.24 g biomass from 100 seeds. This study indicates that transgenic Arabidopsis plants having ophB gene increase the tolerance level of organophosphate pesticides. [ABSTRACT FROM AUTHOR]

A voltammetric biosensor for acetylthiocholine (ATCh) and paraoxon detection was successfully developed. To achieve this goal, polypyrrole (PPy) was synthesized onto the platinum (Pt) electrode surface in 0.30 M oxalic acid solution containing 25 mM pyrrole. PPy‐coated Pt (Pt/PPy) electrode surface was covered with chitosan (Chi) (Pt/PPy/Chi). The acetylcholinesterase (AChE) enzyme was immobilized on the Pt/PPy/Chi electrode surface to build a voltammetric biosensor (Pt/PPy/Chi/AChE). The storage stability of the biosensor was determined to be 72% even after 60 days. The operational stability was determined to be 94% after 20 consecutive measurements. For the biosensor, the linear range was determined to be 30–50 µM for ATCh and 0.46–1.84 nM for paraoxon. The limit of detection (LOD) was determined to be 0.45 µM for ATCh and 0.17 nM for paraoxon [ABSTRACT FROM AUTHOR]

A graft copolymer was prepared by grafting a mixture of 2‐acrylamido‐2‐methyl propane sulfonic acid (AMPS) and acrylic acid (AA) monomers onto the dextrin polysaccharide backbone by free radical copolymerization technique using potassium peroxydisulfate as an initiator in water medium. Several characterization techniques like FT‐IR, 1H and 13C NMR, XRD, SEM, and EDAX analyses were used to characterize the synthesized polymer. The polymer was used as an efficient adsorbent for the removal of toxic pesticides namely dimethoate (DM), chlorpyrifos (CP), and phosalone (PL) from their aqueous solutions. Various operating variables such as kinetic, isotherm, and thermodynamic parameters were investigated for the three pesticides. The pesticide adsorption process over polymer surface was directed by pseudo‐second‐order kinetic model. Langmuir and Dubinin–Radushkevich isotherms both correlate well with the equilibrium data. Maximum adsorption capacity (qm) of the polymer was found to be 172.4 mg g−1 for DM, 121.95 mg g−1 for PL, and 108.69 mg g−1 for CP. Thermodynamic parameters showed that the selected pesticides' adsorption onto the polymers was a spontaneous and endothermic process. The preferential pesticide sorption by the graft copolymer followed the order DM>PL>CP. [ABSTRACT FROM AUTHOR]

With the development of modern agriculture, the pollution caused by the use of chemical fertilizers and pesticides has become a serious problem, posing a threat to human health and the living environment. The remediation of plant microorganisms has been seen as an economical, effective, and eco-friendly method of cleaning up soils contaminated with organophosphorus pesticides. In this study, white-rot fungi were immobilized by adsorption method, a plant-microbial remediation met was established. The data results show that after 30 days, the combined remediation system for corn microbes increased the rate of chlorpyrifos degradation by 18% compared to the single remediation of the plant, and the rate of combined remediation of ryegrass microbes increased by 23%. The effect of CPF content in soil on the combined remediation is mainly reflected in the significant difference in the number of microorganisms (P < 0.05). In this article, plant-microbial remediation were applied to soil contaminated by CPF, which provides a new idea for the remediation of pesticide-contaminated soil. Combined bioremediation may be a better alternative to mitigate the impact of high pollution on microorganisms at different pollutant concentrations compared to single microbial remediation or phytoremediation. [ABSTRACT FROM AUTHOR]

Introduction/purpose: In this study, we investigated the possibility of removing the organophosphorus pesticide malathion from water using a new adsorbent based on the biowaste of river shell shards from the Anodonta Sinadonta woodiane family, a material that accumulates in large quantities as waste on the banks of large rivers. Two adsorbents were tested - mechanically comminuted river shells (MRM) and mechanosynthetic hydroxyapatite from comminuted river shells (RMHAp). Methods: The obtained adsorbents were characterized and tested for the removal of the organophosphorus pesticide malathion from water. In order to predict the optimal adsorption conditions using the Response Surface Method (RSM), the authors investigated the influence of variable factors (adsorption conditions), pH values, adsorbent doses, contact times, and temperatures on the adsorbent capacity. Results: The best adsorption of malathion was achieved at mean pH values between 6.0 and 7.0. The adsorption data for malathion at 25, 35, and 45 °C were compared using the Langmuir, Freundlich, Dubinin- Radushkevich (DR), and Temkin isothermal models, as well as pseudofirst order, pseudo-second order and Elovic kinetic models for modeling adsorption kinetics. The maximum Langmuir adsorption capacity for MRM and RMHAp at 25 °C was 46,462 mg g-1 and 78,311 mg g-1, respectively. Conclusion: The results have showed that malathion adsorption on both adsorbents follows the pseudo-second kinetic model and the Freundlich isothermal model. The thermodynamic parameters indicate the endothermic, feasible, and spontaneous nature of the adsorption process. [ABSTRACT FROM AUTHOR]

Background and Objective: The Pesticides used in agriculture have caused great concern due to their adverse effects on human health. In this study, the effect of rinsing, crushing, filtering, clarifying with bentonite and pasteurization on the reduction of diazinon, ethion and phosalone during Asari grape juice was investigated. Materials and Methods: Vineyard was sprayed during three growth stages before flowering, sour grape (ghooreh) and during grape ripening with phosalone, diazinon, ethion and in doses of 525, 600, 750 g of active substance per hectare, respectively. Twenty-four hours after the last spraying step, the grape sample was harvested and exposed to the process of rinsing (20-30 s), crushing, filtering, clarifying and pasteurizing. Then, the pesticides residue concentration was determined after each step by GC-MS/MS. Results: The initial concentrations of diazinon, ethion and phosalone in unprocessed grape samples were 0.640, 0.716 and 0.550 mg/kg, respectively. The reduction values of diazinon during the juicing processes of rinsing, crushing, filtering, clarifying with bentonite and pasteurization, in comparison with the concentration of unprocessed grapes, were 25.72, 41.96, 74.54, 90.21 and 100% (not found), respectively; while these values were 9.78, 28.50, 69.45, 89.38 and 96.74% for ethion and 17.32, 28.47, 46.40, 80.25, 93.28% for phosalone, respectively. All processes significantly reduced insecticides residue. Conclusion: Findings showed that the processes of grape juice production could significantly decrease the diazinon, ethion and phosalone residues. [ABSTRACT FROM AUTHOR]

A new electrochemical sensor for organophosphate pesticide (methyl-paraoxon) detection based on bifunctional cerium oxide (CeO 2) nanozyme is here reported for the first time. Methyl-paraoxon was degraded into p -nitrophenol by using CeO 2 with phosphatase mimicking activity. The CeO 2 nanozyme-modified electrode was then synthesized to detect p -nitrophenol. Cyclic voltammetry was applied to investigate the electrochemical behavior of the modified electrode, which indicates that the signal enhancement effect may attribute to the coating of CeO 2 nanozyme. The current research also studied and discussed the main parameters affecting the analytical signal, including accumulation potential, accumulation time, and pH. Under the optimum conditions, the present method provided a wider linear range from 0.1 to 100 μmol/L for methyl-paraoxon with a detection limit of 0.06 μmol/L. To validate the proof of concept, the electrochemical sensor was then successfully applied for the determination of methyl-paraoxon in three herb samples, i.e., Coix lacryma-jobi, Adenophora stricta and Semen nelumbinis. Our findings may provide new insights into the application of bifunctional nanozyme in electrochemical detection of organophosphorus pesticide. [Display omitted] • A new electrochemical method for methyl-paraoxon detection by using bifunctional nanozyme was presented. • The cerium oxide nanozyme modified glassy carbon electrode was prepared to improve the sensitivity. • The developed method has been successfully applied in three herbal plant samples. [ABSTRACT FROM AUTHOR]

• Bionic modulation of catalytic activity of MOF nanozymes via a facile approach. • Increasing the amount of histidine modification to enhance the catalytic activity. • The established structure-activity of MOF nanozyme can direct practical sensing. • Pesticide detection by the sensor arrays is highly discriminatory and quantitative. Biosensors provide simple, rapid and sensitive detection of a wide range of analytes. Recently, they have been widely used for the rapid detection of pesticides, which makes up for the shortcomings of traditional detection methods. However, the catalytic activity of some nanozymes is not satisfactory in practical applications, limiting the performance of biosensors. Further development of highly active and stable nanozymes is conducive to improving the sensitivity of the sensors and expanding their application in practical detection. Herein we simulated the amino acid microenvironment of natural enzymes and synthesized His-MIL-101(Fe)-X with different histidine (His) modification amounts (X = 0, 25%, 50%, 75%) by regulating the ratio of histidine and terephthalic acid ligands using a one-step solvothermal method. With increasing histidine doping, the peroxidase-like activity of His-MIL-101(Fe)-X was gradually enhanced, and the sensing performance of the sensor arrays constructed by combining His-MIL-101(Fe)-X with three peroxidase substrates was also gradually improved, with a 25-fold increase in detection limit. The His-MIL-101(Fe)-75% sensor array was not only able to accurately discriminate five pesticides in the range of 2-100 μM, but also to quantitatively identify different concentrations of pesticides. Moreover, the His-MIL-101(Fe)-75% sensor array showed good anti-interference capability and was able to discriminate five pesticides at only 2 μM in soil, lake water, seawater, and apple samples, as well as quantitatively detecting diafenthiuron, which has great potential for practical application. [ABSTRACT FROM AUTHOR]

Methyl parathion (MP) is a highly toxic organophosphorus pesticide associated with water, soil, and air pollution events. The identification and characterization of microorganisms capable of biodegrading pollutants are an important environmental task for bioremediation of pesticide impacted sites. The strain Burkholderia cenocepacia CEIB S5-2 is a bacterium capable of efficiently hydrolyzing MP and biodegrade p-nitrophenol (PNP), the main MP hydrolysis product. Due to the high PNP toxicity over microbial living forms, the reports on bacterial PNP biodegradation are scarce. According to the genomic data, the MP- and PNP-degrading ability observed in B. cenocepacia CEIB S5-2 is related to the presence of the methyl parathion-degrading gene (mpd) and the gene cluster pnpABA'E1E2FDC, which include the genes implicated in the PNP degradation. In this work, the transcriptomic analysis of the strain in the presence of MP revealed the differential expression of 257 genes, including all genes implicated in the PNP degradation, as well as a set of genes related to the sensing of environmental changes, the response to stress, and the degradation of aromatic compounds, such as translational regulators, membrane transporters, efflux pumps, and oxidative stress response genes. These findings suggest that these genes play an important role in the defense against toxic effects derived from the MP and PNP exposure. Therefore, B. cenocepacia CEIB S5-2 has a great potential for application in pesticide bioremediation approaches due to its biodegradation capabilities and the differential expression of genes for resistance to MP and PNP. [ABSTRACT FROM AUTHOR]

The extensive use of pesticides requires innovative approaches to remove these compounds from the environment. Carbon materials are traditionally used as adsorbents for removing pesticides, and the development of the new sorts of carbon materials allows more advanced approaches in environmental applications. Using density functional calculations, we have predicted chemical reaction between the S(O)=P moieties of the organophosphates with point defects in graphene - single vacancies, Stone-Wales defects and epoxy--groups. The reaction was confirmed using ultra high performance chromatography for two graphene oxide samples and dimethoate as a representative of organophosphates. The exact reaction mechanism is still elusive, but it is unambiguously confirmed that no selective oxidation of dimethoate to more toxic oxo-analog occurs. The presented results can help to develop novel systems for the irreversible conversion of organophosphates to non-toxic compounds, without using aggressive chemical agents or external physical factors like UV radiation. [ABSTRACT FROM AUTHOR]

Pesticides application is expanding globally as the worldwide population increases demanding a secure and safe food supply. Organophosphorus (OP) pesticides, as a group, are widely used because they are rapidly degraded in the environment and because they have excellent efficacy and an acceptable price point. However, the chemical fate of organophosphorus pesticides is influenced by several factors, including their chemistry in aquatic environments. Among many degradation choices, hydrolysis by metal ions appears to be a good approach. Dissolved metal ions have been shown to promote the hydrolysis of organophosphorus pesticides. Using silver ion, we showed the effectiveness under in vitro and in vivo conditions for this metal ion to decontaminate water polluted by the organophosphorus phosalone. Phosalone was completely degraded in the presence of silver ions in a mole ratio of 7:1 in 20 min. Rainbow trout were divided into experimental groups to investigate the most effective ratio of silver/phosalone for pesticide degradation. Silver ion (2%) at a concentration of 0.75 and 0.1 mL removed phosalone (2%) at concentrations of 0.4 and 0.5 mL. All the rainbow trout survived in these two groups. This experiment suggested that silver ions can be beneficial at ratios in the range of 1:4 to 1:6 by hydrolyzing phosalone by attacking the electron-deficient phosphorus atom in the pesticide [ABSTRACT FROM AUTHOR]

Featured Application: Authors are encouraged to provide a concise description of the specific application or a potential application of the work. This section is not mandatory. The aim of this work is to detect acetamiprid using electrochemical capacitance spectroscopy, which is widely used as a pesticide in agriculture and is harmful to humans. We have designed aptasensing platform based on the adsorption of a DNA aptamer on lipoic acid-modified MoS2 nano-sheets. The biosensor takes advantage of the high affinity of single-stranded DNA sequences to MoS2 nano-sheets. The stability of DNA on MoS2 nano-sheets is assured by covalent attachment to lipoic acid that forms self-assembled layer on MoS2 surface. The biosensor exhibits excellent capacitance performances owing to its large effective surface area making it interesting material for capacitive transduction system. The impedance-derived capacitance varies with the increasing concentrations of acetamiprid that can be attributed to the aptamer desorption from the MoS2 nanosheets facilitating ion diffusion into MoS2 interlayers. The developed device showed high analytical performances for acetamiprid detection on electrochemical impedance spectroscopy EIS- derived capacitance variation and high selectivity toward the target in presence of other pesticides. Real sample analysis of food stuff such as tomatoes is demonstrated which open the way to their use for monitoring of food contaminants by tailoring the aptamer. [ABSTRACT FROM AUTHOR]

Ever increasing demand for food and agricultural resources have led to escalation of pesticide poisoning and environmental hazards. An efficient system for pesticide detection is a constant endeavour and several technologies are working hand in hand to generate effective biosensors for various classes of pesticides. Innovative technologies are being developed for pesticides detection which overcome issues such as time and costs involved in sample preparation. Moreover, improvements in ease of operation and better sensitivity have been achieved using techniques such as fluorescence spectroscopy and electrochemical methods. Many tools such as aptamers, gold nanoparticles, quantum dots, molecularly imprinted polymers and, antibodies are used to develop hybrid biosensors where the sensitivity is increased several folds and limit of detection is as low as 0.1 pM. The time of detection is reduced to minutes along with simultaneous detection of multiple pesticides using the biosensors. We reviewed the latest biosensors developed which can be utilized for on-site sensing and optical biosensors are at the forefront of technology with advantages such as easy protocols, simple operation, high sensitivity, broad linearity range and cost-effectiveness. Colorimetric and fluorescence biosensors have rapid detection of pesticides with 90% recovery in food and serum samples. Chemiluminescence utilising biosensors have low detection time while photoluminescent sensors are highly sensitive and can be easily combined with smartphones for real-time detection. Many commercially available Surface Enhanced Raman Scattering (SERS) substrates are also present. For a cost-effective point-of-care biosensor, sample pre-treatment and expensive instrumentation are few hurdles that are conquered in electrochemical sensors. With amperometric, impedimetric and potentiometric techniques used in these biosensors, a low detection limit and time is observed in agriculture, water and food samples containing variety of pesticides. The review covers all the major techniques which can potentially be used for the development of point-of care biosensors such as, colorimetric, fluorescence, chemiluminescence, photoluminescence, surface enhanced Raman scattering and electrochemical in detailed and up-to-date analysis. [ABSTRACT FROM AUTHOR]

An electrochemical biosensor for organophosphorus pesticides detection has been developed by immobilizing acetylcholinesterase (AChE) enzyme, through a multi-step functionalization process, on porous silicon (PSi) surface. The PSi surface was functionalized using thermal hydrosilylation creating acidic chains to stabilize the surface. The AChE was covalently attached on the PSi surface and exhibited a good enzyme activity in the presence of its substrate acetylthiocholine iodide (ATI) by forming thiocholine. The response of the device shows a linear evolution over a wide concentration range of ATI from 0.15 to 0.65 mM with a good correlation coefficient. Furthermore, AChE revealed high affinity to its substrate ATI from calculated Michaelis–Menten constant (Km), which is about 0.249 mM. The effect of the organophosphorus pesticide malathion was monitored by measuring the current oxidation in ATI solution. After incubation, it shows a drastic decrease in the electrochemical response in the presence of the pesticide at different concentrations (2–8 nM). [ABSTRACT FROM AUTHOR]

We developed a highly sensitive and selective method for double-signal analysis (fluorescence and ultraviolet–visible spectrophotometry) of organophosphorus pesticides (OPs), based on reversible quenching of graphene quantum dots (GQDs; fluorophores) with silver nanoparticles (AgNPs; absorbers). We used acetylcholinesterase to catalytically convert acetylthiocholine into thiocholine. In turn, by competitive binding to the AgNPs, the produced thiocholine displaces AgNPs from the GQDs and thus induces fluorescence recovery. However, OP analytes inhibit the activity of acetylcholinesterase and, in so doing, retain the silver–graphene nanoparticle complex and fluorescence quenching. The degree of quenching is proportional to the concentration of OPs; the detection limit is as low as 0.017 μg/L. The ultraviolet–visible absorption of GQDs/AgNPs at 390 nm decreases—because of AgNP aggregation that occurs after desorption from the GQDs—and the absorbance is linearly proportional to the OP concentration. Our system has good selectivity to substances that are commonly present in water and vegetables. We successfully applied our method to OP analysis in water, apple, and carrot samples. [ABSTRACT FROM AUTHOR]

Microencapsulation of pesticide can reduce mammalian toxicity, phyto-toxicity, and protect the pesticides from rapid environmental degradation. The aim of this study was to develop a liquid-driven coaxial flow focusing (LDCFF) process for fabricating pesticide-loaded microcapsules having high encapsulation efficiency, loading efficiency and yield. We have optimized and evaluated the effects of process parameters on the size and morphology of pesticide-loaded microcapsules. The release of pesticides from pesticide-loaded microcapsules has sustained release profiles, which depends on their core-shell structure and shell material degradation process. LDCFF process enables successful encapsulation of pesticides in microcapsules with tunable characteristics important in pesticide applications. [ABSTRACT FROM AUTHOR]

Food contaminants are challenging the food industry due to the inefficiency of conventional decontamination techniques. Cold plasma as an emerging technique for the degradation of food contaminants attracted notable attention. The current study overviews the plasma-induced degradation of food contaminants, discusses the mechanisms involved, points its benefits and drawbacks out, highlights the research needed in this area, and explores future trends. According to the literature, cold plasma efficiently degraded many common pesticides (e.g. parathion, paraoxon, omethoate, dichlorvos, malathion, azoxystrobin, cyprodinil, fludioxonil, cypermethrin, and chlorpyrifos) and food allergens (e.g. tropomyosin, b-conglycinin, glycinin, trypsin inhibitor, and Kunitztype trypsin inhibitor). These degradations occurred primarily due to the presence of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in the plasma that attack the chemical bonds of food contaminants. The type of pesticide degrades are highly dependent on the concentrations of plasma-generated ROS and RNS. Research showed that several parameters, such as plasma generation device, plasma exposure time, plasma power, and the carrier gas composition, influence the type and concentration of reactive species (e.g. ROS and RNS) and the overall efficiency of cold plasma degradation for a specific pesticide or allergen.HighlightsCold plasma can be used for degradation of many types of pesticides and allergens.Plasma-generated reactive species and UV can interact with pesticides and allergens.The scaled up removal of pesticides and allergens by plasma can be challenging. [ABSTRACT FROM AUTHOR]

Pesticide residues are one of the major food safety concerns for consumers all over the world, and it is crucial to develop simple, rapid, and effective method for the detection of pesticide residues. In the study, we report the sensitive detection of pesticides with the dynamic surface‐enhanced Raman spectroscopy (dynamic SERS) method. The dynamic SERS method provides excellent detection sensitivity at the metastable state of plasmonic nanoparticles in the sessile drop, which is a critical state between the wet state and dry state during the volatilization process. With this simple and rapid method, the SERS performance towards four pesticides, paraquat, thiabendazole, tricyclazole, and isocarbophos, is investigated with silver nanoparticles (AgNPs) as the enhancing reagents. The characteristic SERS spectra of paraquat, thiabendazole, tricyclazole, and isocarbophos can be detected at concentrations down to 1 × 10−9 M, 5 × 10−9 M, 5.28 × 10−9 M, and 3.45 × 10−7 M, respectively. The pesticides are also discriminable at the same concentrations as the standard solution counterparts from the pesticides spiked vegetable extracts, and linear relationship can be drawn from the characteristic peak intensities and negative logarithm of concentrations of the four pesticides. Therefore, the simple and rapid dynamic SERS method shows great potential in the practical detection of pesticide residues. [ABSTRACT FROM AUTHOR]

Environmental contamination can negatively impact fish populations. In addition to acute toxicity leading to death, toxicants can reduce fish growth and lower reproduction. The potential for adverse population level effects of environmental contaminants are estimated to conduct risk assessments from laboratory toxicity tests that most often measure apical endpoints related to growth, survival and reproduction. The relationships between these effect endpoints are being evaluated to predict shifts in fish population demography better after exposure to environmental toxicants. Environmental contaminants can also affect fish populations indirectly by reducing prey biomass. However, estimating the magnitude of the combined effects of prey reduction and direct toxicity is difficult and rarely attempted. Here we describe a toxicity test designed to estimate the effect on Japanese medaka of both reduced food and chronic exposure to diazinon, an acetylcholinesterase inhibiting organophosphate pesticide. Fish were reared with limited food ration and/or diazinon exposure through a full life cycle to assess possible interactions between the two stressors in their effects on growth and reproduction. Diazinon exposure (10 or 20 μg/L), reduced ration (50% and 25% of ad libitum), or combinations of both lowered growth rates and reproductive output of Japanese medaka. In addition, growth and reproduction alone were modeled, and then various relationships between the two stressors (diazinon and ration) and how they relate to growth and reproduction were modeled. Study describes a toxicity test in which fish were reared with limited food ration and/or diazinon exposure through a full life cycle, showing that diazinon exposure, reduced ration, or combinations of both lowered growth rates and reproductive output of Japanese medaka. In addition, growth and reproduction alone were modeled, and then various relationships between the two stressors (diazinon and ration) and how they relate to growth and reproduction were modeled. [ABSTRACT FROM AUTHOR]