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In this study, a QuEChERS method based on citrate was developed and utilized for the analysis of twelve neonicotinoid pesticides in fresh red chilies, fresh green chilies, and dried chilies, coupled with ultra-high performance liquid chromatography quadrupole time of flight mass spectrometry (UPLC-Q-TOF/MS). In the sample preparation, acetonitrile containing 1% formic acid was used as the extraction solvent. Anhydrous sodium sulfate replaced the traditional anhydrous magnesium sulfate for water removal, effectively eliminating the issues of salt caking. Graphitized carbon black, octadecyl silica, and primary secondary amine were used as cleaning agents. The method showed good sensitivity, with the limits of quantification below 0.03 mg/kg for fresh chilies and below 0.15 mg/kg for dried chilies. Values of matrix effects ranged from −19.5% to 8.4%, and the recovery was 86.9% - 105.2%. The analytical method provided an effective tool for the high throughput detection of neonicotinoid pesticide residues in multiple chili matrices. [Display omitted] • Twelve neonicotinoid pesticides were effectively analyzed using a modified QuEChERS method. • Anhydrous sodium sulfate was used to avoid the impact of salt caking. • Cleaning agents effectively removed interfering substances in chili. • Validation data demonstrated satisfactory performance of the developed method. • The method was applied for the analysis of neonicotinoid pesticides in multi-matrix. [ABSTRACT FROM AUTHOR]

• An UPLC-MS/MS 5-window-method enduring 22 min has been optimized. • This sensitive and accurate method allows to quantify 23 pesticides in human urine. • The optimization includes 3 further pesticide groups: neonicotinoids, carbamates and triazoles. • Pesticides still in use and others already banned by legislations are included. • This method is optimal as a HBM tool for health risk assessment in large population surveys. An accurate and sensitive method for the determination of a total of 23 pesticides and their metabolites in human urine has been optimised. The methodology is based on a previously published method based on solid-phase extraction with methanol and acetone followed by ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) in the selected reaction mode (SRM) with both positive and negative electrospray ionization (ESI+/-). The detection settings of the previous method, which allowed to determine the metabolites from 6 organophosphate and 2 pyrethroid pesticides, were optimised in order to include further pesticide groups, such as 11 neonicotinoids, 3 carbamates/thiocarbamates and 2 triazoles. The 5-windows method enduring 22 min was optimized with acceptable results in relation to accuracy (recoveries >75 %), precision (coefficients of variation <26 %) and linearity (R2> 0.9915). The limits of detection ranged between 0.012 ng/mL and 0.058 ng/mL. Samples from the German External Quality Assessment Scheme (G-EQUAS) encompassing 2 pyrethroids, 2 organophosphate and one neonicotinoid (6-chloronicotinic acid, a common metabolite of imidacloprid and acetamiprid) were analysed, and the latter, included in this newest optimization, provided good reference results. The method is optimal as a human biomonitoring tool for health risk assessment in large population surveys. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biogenic activated carbon with a strong affinity for neonicotinoid pesticides. • Continuous adsorption of multicomponent solutions using sludge-derived materials. • Mesopority of the novel material promoted adsorption kinetics. • FBU values reaching up to 71%, compared to 7–8% for commercial adsorbent. • Regeneration of the fixed bed for reuse was successfully accomplished. The environmental impact of pesticides, together with the increasing regulatory framework on sewage sludge disposal, has raised a great political and social concern. Neonicotinoid pesticides, such as imidacloprid (IMD), thiamethoxam (THM), and acetamiprid (ACT), have been included among the main emerging pollutants on the latest EU Watch Lists derived from Directive 2008/105/EC. This research aims at valorising an industrial sludge through the synthesis of a biogenic activated carbon for the continuous adsorption of the aforementioned plaguicides from multicomponent aqueous solutions. AC-Industrial2 was prepared by combining chemical and physical activation, resulting in a mesoporous material with a high surface area (S BET = 750 m2∙g−1) and a strong affinity for the micropollutants tested. The sludge-derived adsorbent achieved maximum adsorption capacity values at equilibrium of 124.3, 124.4 and 153.1 mg∙g−1 for ACT, THM and IMD, respectively. Therefore, this material not only presented similar removal yields to those obtained with the commercial material (AC-F400), but also it considerably favoured the adsorption kinetics due to its great mesoporosity contribution. The best fitting of experimental kinetic data was found by using pseudo-first order model, while Freundlich model successfully fitted most of the equilibrium adsorption isotherms. The breakthrough behaviour of the multicomponent fixed-bed system for AC-Industrial2 was related to the pesticides' hydrophobicity, rather than the molecular volume of the pollutants. Additionally, an overshooting phenomenon was noticed for the weakest adsorbable components (THM and ACT). The sorbent developed in this work allowed a bed utilisation in the range 51–67.2 %, whereas the commercial material led to values between 7.0 and 8.3 %. This fact, together with the complete and efficient regeneration of the novel material by a Fenton process, highlighted its excellent reusability and stability for scale-up. [ABSTRACT FROM AUTHOR]

The excessive residue of neonicotinoid pesticides in the environment and food poses a severe threat to human health, necessitating the urgent development of a sensitive and efficient method for detecting trace amounts of these pesticides. Electrochemical sensors, characterized by their simplicity of operation, rapid response, low cost, strong selectivity, and high feasibility, have garnered significant attention for their immense potential in swiftly detecting trace target molecules. The detection capability of electrochemical sensors primarily relies on the catalytic activity of electrode materials towards the target analyte, efficient loading of biomolecular functionalities, and the effective conversion of interactions between the target analyte and its receptor into electrical signals. Electrode materials with superior performance play a crucial role in enhancing the detection capability of electrochemical sensors. With the continuous advancement of nanotechnology, particularly the widespread application of novel functional materials, there is paramount significance in broadening the applicability and expanding the detection range of pesticide sensors. This comprehensive review encapsulates the electrochemical detection mechanisms of neonicotinoid pesticides, providing detailed insights into the outstanding roles, advantages, and limitations of functional materials such as carbon-based materials, metal-organic framework materials, supramolecular materials, metal-based nanomaterials, as well as molecular imprinted materials, antibodies/antigens, and aptamers as molecular recognition elements in the construction of electrochemical sensors for neonicotinoid pesticides. Furthermore, prospects and challenges facing various electrochemical sensors based on functional materials for neonicotinoid pesticides are discussed, providing valuable insights for the future development and application of biosensors for simplified on-site detection of agricultural residues. This comprehensive review encapsulates the electrochemical detection mechanisms of neonicotinoid pesticides, providing detailed insights into the outstanding roles, advantages, and limitations of functional materials such as carbon-based materials, metal-organic framework materials, supramolecular materials, metal-based nanomaterials, as well as molecular imprinting materials, antibodies/antigens, and aptamers as molecular recognition elements in the construction of electrochemical sensors for neonicotinoid pesticides. Simultaneously, the challenges faced by various neonicotinoid pesticide electrochemical sensors based on functional materials and future prospects are thoroughly explored. [Display omitted] • Review explores the electrochemical detection mechanisms for neonicotinoids. • Article examines the signal amplification strategy employing various functional materials and nucleic acid self-assembly. • Review explores the different electrochemical signal transduction modes for neonicotinoids detection. [ABSTRACT FROM AUTHOR]

• RAMs is devised to enrich neonicotinoid pesticides while exclude proteins. • RAMs possess dual-function adsorption sites and zwitterionic polymer exclusion sites. • Offline and online RAMs couple with LC show the potential in the detection of neonicotinoid pesticides from Goji samples. • Online RAMs-LC is able to complete extraction-detection of neonicotinoid pesticides into one step by simple valve-switching. A method based on novel restricted access materials (RAMs) for the determination of neonicotinoid pesticides in Goji samples using offline and online solid phase extraction (SPE) coupled with high-performance liquid chromatography (LC). RAMs were synthesized using poly(chloromethylstyrene- co -divinylbenzene) (P VBC/DVB) microspheres as substrate, styrene (St) and n-vinylpyrrolidone (NVP) were first copolymerized on the interior to construct adsorption sites, and sulfobetaine methacrylate (SBMA) was then polymerized on the exterior to form exclusion sites via two-step surface initiated-atom transfer polymerization. The prepared P VBC/DVB @poly(St- co -NVP)@poly(SBMA) RAMs could efficiently extract neonicotinoid pesticides and automatically exclude proteins. Under the optimized conditions, the developed methods of offline (magnetic SPE and SPE column) and online extraction coupled with LC both using P VBC/DVB @poly(St- co -NVP)@poly(SBMA) RAMs as the extractant, exhibit a wide linearity, low limits of detection and limit of quantification and good inter-day and intra-day precision with satisfactory recoveries. Among these methods, online extraction coupled with LC based on novel RAMs exhibits clear advantages for the determination of neonicotinoid pesticides in Goji samples has clear advantages, such as simple operation by direct injection, short extraction times, and high accuracy with less human error. [ABSTRACT FROM AUTHOR]

Incorrect use of neonicotinoid pesticides poses a serious threat to human and pollinator health, as these substances are commonly present in bee products and even drinking water. To combat this threat, the study developed a new method of degrading the pesticide imidacloprid using surface discharge cold plasma oxidation technology. The study showed that this method achieved a very high efficiency of imidacloprid degradation of 91.4%. The main reactive oxygen species (H 2 O 2 , O 3 , · OH, O 2 -, 1O 2) effectively participated in the decomposition reaction of imidacloprid. Reactive oxygen species were more sensitive to the structure of the nitroimine group. Density functional theory (DFT) further explored the sites of reactive oxygen species attack on imidacloprid and revealed the process of energy change of attacking imidacloprid. In addition, a degradation pathway for imidacloprid was proposed, mainly involving reactive oxygen species chemisorption, a ring-opening intermediate, and complete cleavage of the nitroimine group structure. Model predictions indicated that acute oral and developmental toxicity were significantly reduced after cold plasma treatment, as confirmed by insect experiments. Animal experiments have shown that plasma treatment reduces imidacloprid damage to mice hippocampal tissue structure and inhibits the reduction of brain-derived neurotrophic factor content, thus revealing the detoxification mechanism of the body. [Display omitted] • A new energy-efficient method for discharge cold plasma degradation of imidacloprid is proposed. • 91.4% of imidacloprid was removed in the cold plasma system within 40 min. • 1O 2 , O 2 –and •OH generated in the cold plasma process contributed to imidacloprid decomposition. • The sensitive sites for ROS attack on imidacloprid molecules were predicted by DFT calculations. • Possible imidacloprid degradation pathways and toxicity assessment are proposed. [ABSTRACT FROM AUTHOR]

Multiple pesticides are often used in combination to protect crops from pests. This makes rapid on-site detection of pesticide contamination challenging. Herein, we describe a method for simultaneous detection of diverse neonicotinoid pesticides using a sensor that combines neonicotinoid-specific odorant-binding protein 2 (OBP2), which was cloned from an insect chemical sensing protein and modified gold nanoparticles with local surface plasmon resonance (LSPR)-based digital nanoplasmonometry (DiNM). When neonicotinoid pesticides bind to OBP2 on gold nanoparticles, the induced LSPR shift peak wavelength is too small to be measured using conventional LSPR immunoassays. DiNM records and compares the scattered image intensity in two adjacent wavelength bands, A and B, centered on the LSPR peak. It considers both the peak shift and the relative intensity change in these two bands, resulting in a significant LSPR signal enhancement. Then the spectral-image contrast was computed as the signal response. Using this approach, we obtained excellent limits of detection (LODs) of 1.4, 1.5, and 4.5 ppb for the neonicotinoids imidacloprid, acetamiprid, and dinotefuran, respectively. Blind tests demonstrated high positive and negative rates for teas, approximately 85 and 100%, respectively. Recombinant OBP2 produced in E. coli offers several advantages over antibodies, including high yield, time savings, and cost effectiveness. Moreover, this method is highly selective and sensitive to neonicotinoids, making it practical for field use. • OBP2 displays a broader affinity for neonicotinoids than monoclonal antibodies. • OBP2 expression is higher yield, saves time, and cost-effective than antibodies. • Spectral image contrast and digital analysis enable LSPR direct pesticide detection. • The direct detection with a LOD of ppb levels within 45 min was reached. • Real sample blind test results were consistent with the standard mass spectrometry. [ABSTRACT FROM AUTHOR]

[Display omitted] In this work, a novel magnetic hyper-crosslinked polymers (EA-MHCP1) was facilely synthesized by using biogenic ellagic acid (natural polyphenol) as monomer for the first time. The EA-MHCP-1 showed high extraction capacity toward neonicotinoid pesticides. Thus, it was applied as efficient sorbent to simultaneously extract four of the most frequently used neonicotinoids from environmental water and lettuces, followed by high performance liquid chromatography-diode array detection. This work provided a fast, reliable and sensitive tool for neonicotinoids detection. • A novel magnetic HCP (EA-MHCP) was facilely synthesized using biogenic ellagic acid. • EA-MHCP showed large adsorption capacity and fast adsorption rate to neonicotinoids. • H-bond and Lewis acid-base interaction may be the main adsorption mechanism. • EA-MHCP was applied as MSPE sorbent to detect neonicotinoids in water and lettuce. • EA-MHCP exhibited good application prospect for organic compounds with big polarity. Three hydroxyl-functionalized magnetic hyper-crosslinked polymers (EA-MHCPs) were facilely synthesized using biogenic ellagic acid (EA) as monomer for the first time. The EA-MHCP1 possessed large surface area, good magnetism and excellent extraction capability toward neonicotinoids. Thus, an EA-MHCP1 based magnetic solid phase extraction method coupled with HPLC was developed for simultaneous analysis of four neonicotinoids in water and lettuce samples. At optimized conditions, excellent linear response (R2 ≥ 0.9990) was observed in the range of 0.06–100 ng mL−1 for water and 2.5–250 ng g−1 for lettuce. Low detection limits (S/N = 3) were obtained over the range of 0.02–0.03 ng mL−1 for environmental water and 0.8–3.2 ng g−1 for lettuce samples. Good method recoveries ranging from 80.0 % to 116 % were obtained, with relative standard deviations below 7.1 %. This work provided a robust analysis method for sensitively determining neonicotinoid residues in real samples. [ABSTRACT FROM AUTHOR]

• All four neonicotinoids exhibit photo-enhanced toxicity to V. fischeri with different toxic responses because of diverse photolysis mechanism for different main structure. • ROSs play important roles in the photolysis process and photo-enhanced toxicity. • A developed theoretical equation can well explain the toxicity variations of four neonicotinoids. Neonicotinoids are widely used pesticides that contaminate aquatic environments. Although these chemicals can be photolyzed under sunlight radiation, it is unclear for the relationship between photolysis mechanism and toxicity change in aquatic organisms. This study aims to determine the photo-enhanced toxicity of four neonicotinoids with different main structures (acetamiprid, and thiacloprid for cyano-amidine structure, imidacloprid and imidaclothiz for nitroguanidine). To Achieve the goal, photolysis kinetics, effect of dissolved organic matter (DOM) and reactive oxygen species (ROSs) scavengers on photolysis rates, photoproducts, and photo-enhanced toxicity to Vibrio fischeri were investigated for four neonicotinoids. The results showed direct photolysis plays a key role in the photo-degradation of imidacloprid and imidaclothiz (photolysis rate constants are 7.85 × 10−3 and 6.48 × 10−3 min−1, respectively), while the photosensitization process of acetamiprid and thiacloprid was dominated by ·OH reactions and transformation (photolysis rate constants are 1.16 × 10−4 and 1.21 × 10−4 min−1, respectively). All four neonicotinoid insecticides exerted photo-enhanced toxicity to Vibrio fischeri , indicating photolytic product(s) posed greater toxicity than their parent compounds. The addition of DOM and ROS scavengers influenced photo-chemical transformation rates of parent compounds and their intermediates, leading to diverse effects on photolysis rates and photo-enhanced toxicity for the four insecticides as a result of different photo-chemical transformation processes. Based upon the detection of chemical structures of intermediates and Gaussian calculations, we observed different photo-enhanced toxicity mechanisms for the four neonicotinoid insecticides. Molecular docking was used to analyze the toxicity mechanism of parent compounds and photolytic products. A theoretical model was subsequently employed to describe the variability of toxicity response to each of the four neonicotinoids. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • A high-throughput automated pipetting system was innovatively combined with DLLME. • Batch samples was processed in-parallel, greatly reducing labor and time costs. • A novel, economical and safe DES was used as extractant solvent. • The semi-automatic DES-VA-DLLME met green analysis principles better than regular DLLME. • The proposed method was successfully applied to the detection of neonicotinoid residues in edible oils. In this study, a high-throughput automated pipetting system was innovatively combined with dispersive liquid–liquid microextraction (DLLME). This application automates the sample and solvent addition steps in DLLME and allows simultaneous batch sample processing, thereby, greatly saving labor and time. The use of a deep eutectic solvent (DES) instead of traditional organic solvents as the extractant makes the whole extraction process environmental-friendly. Under optimized conditions, the method exhibits satisfactory extraction performance for all target analytes. The limits of detection for thiamethoxam, imidacloprid, and thiacloprid in the rapeseed oil matrix are 5.8, 2.9, and 2.7 μg L−1, respectively. It is worth mentioning that this high-throughput automatic pipetting system can be applied to different types of DLLME. Furthermore, the greenness of the established method is evaluated using the AGREE metric and the results show distinct advantages, such as fast operation, automation, and environmental friendliness, compared to previously published works for the detection of neonicotinoids in edible oils. [ABSTRACT FROM AUTHOR]

[Display omitted] • Enhanced removal of neonicotinoid pesticides with sustainable solvents. • Matrix effect and temperature influence on pesticides extraction from river water. • Novel use of pure terpenoid carvacrol for the removal of neonicotinoid pesticides. • Complete extraction of pesticides at low Solvent/Feed ratios. The potential environmental impact and adverse effects of the occurrence of pesticides in the aquatic environment have raised great social and political concern, leading to their control by means of several regulations, such as the European Directive 98/83/EC. In this regard, the three neonicotinoid pesticides analyzed in this work (acetamiprid, imidacloprid, and thiamethoxam) have been included in the surface water European Watch Lists under the Water Framework Directive. This research proposes the use of terpenoid-based solvents for the extraction of the three emerging contaminants previously mentioned. An initial screening of the extraction solvents was carried out through the COSMO-RS methodology, selecting the most favourable pure terpenes, eutectic terpenoid-based and conventional solvents. Furthermore, relevant issues were experimentally analyzed, such as extraction in more realistic multicomponent mixtures together with key parametric studies covering operating temperature and matrix influence. Carvacrol, a pure terpenoid not applied before as an extraction solvent of pesticides, has been revealed as an effective and sustainable substitute for conventional solvents for the first time to the best of our knowledge. Specifically, carvacrol exhibited overall extraction yields of around 97.5 % from a river water matrix at a volumetric S/F ratio of 0.1 and 303.2 K. High extraction yields from river water matrices regardless of temperature pointed to the potential of this solvent for a wide range of industrial application. [ABSTRACT FROM AUTHOR]

The extensively used neonicotinoid pesticides are reported seriously threatened ecological environment and even human health, which is one of the most urgent environmental problems. In this study, the bioremediation of thiamethoxam contaminated wetland soil by Phanerochaete chrysosporium and the analysis of microorganisms' response was conducted. Results showed that P. chrysosporium improved thiamethoxam degradation both in non-sterilized and sterilized soils. Obvious bioaugmentation of thiamethoxam degradation was especially found in non-sterilized soil at the earlier stage (< 10 d). The pH of the soils increased accompanied with the decreasing in organic matter after remediation. Increase in invertase activity and decrease in urease activity was observed, while the catalase activity changed little. Microbial community analysis illustrated that phyla Proteobacteria , Actinobacteria , Firmicutes , and Bacteroidetes were the dominate species for bacteria, and phyla Ascomycota , Basidiomycota were the dominate species for fungi. P. chrysosporium inoculation in different modes shifted the composition and relative abundance of microbial community differently, but increased in microbial diversity in soil was observed overall. The obtained results proved that white-rot fungus P. chrysosporium enhanced elimination was available for bioremediation of thiamethoxam contaminated soil. [Display omitted] • P. chrysosporium enhanced remediation of THX contaminated soil was confirmed. • THX degradation, soil enzymes, and microbial community varied with inoculated modes. • Increased microbial diversity overall with P. chrysosporium inoculation. [ABSTRACT FROM AUTHOR]

[Display omitted] • •Biochar was produced from Tenebrio molitor frass and modified by KOH. • • TMFBC-750A possessed high S BET of 1858.80 m2g−1 with enhanced absorptivity. • •The prevailing mechanisms of NEOs on BC were revealed. • •TMFBC-750A realized efficient adsorption of NEOs in water. Neonicotinoid pesticides (NEOs) are the most widely used insecticides in the world and pose a serious threat to ecological systems. Thus, the development of an efficient and sustainable technique for their removal is urgently needed. In this study, a novel biochar was prepared by pyrolysis of Tenebrio molitor frass and activated with KOH at 650 (TMFBC-650A), 750 (TMFBC-750A) and 850 °C (TMFBC-850A). Among them, TMFBC-750A showed the best adsorption performance, and the adsorption capacities for thiacloprid (THI), nitenpyram (NIT) and dinotefuran (DIN) were 155.08 mg·g−1, 195.86 mg·g−1, 325.81 mg·g−1, respectively. The isotherms for the adsorption of NIT and THI fit the Langmuir model quite well, while DIN fits the Freundlich model. Moreover, the adsorption of THI, NIT and DIN was well fitted by the pseudofirst-order kinetic model. The physicochemical characterization analysis demonstrated that the adsorption process of NEOs by TMFBC might be mainly controlled by micropore filling, π-π electron donor–acceptor interactions and functional group interactions (H-bonding, covalent bonding and hydrophobic interactions). Additionally, the thermodynamic parameters suggested that NEO adsorption in this work was a spontaneous, endothermic and randomly increasing process. TMFBC also exhibited a high selective adsorption capacity regardless of solution pH and inorganic ion strength concentrations. The regenerated TMFBC (via synergistic ultrasound/ethanol) could sustainably and efficiently absorb NEOs in reuse cycles, suggesting that TMFBC has excellent reusability and stability. These results indicated that TMFBC can be a potential and sustainable adsorbent for neonicotinoid pesticide removal. [ABSTRACT FROM AUTHOR]

Neonicotinoids are widely used pesticides all over the world and pose severe water pollution. Although they can be degraded via absorbing sunlight, few attentions have been paid to the environmental risks of their photolysis products. In this paper, the photo-toxicity was investigated for four neonicotinoids (dinotefuran, nitenpyram, thiamethoxam and clothianidin) based on a series of experiments (i.e., photolysis kinetics, radical scavenging, bioluminescent inhibition test to Vibrio Fischeri and intermediate identification) and in-silico calculation of photolysis pathway. The results show that direct photolysis dominates the photolysis of the four neonicotinoids under simulated sunlight radiation. The bioluminescent inhibition kinetics shows that all four neonicotinoids have photo-induced toxicity to V. fischeri , but with different light-induced responses. Scavenging radicals (·OH and 1O 2) will decrease the photo-induced toxicity of all the four neonicotinoids, indicating radicals play important roles to the photo-chemical reactions of intermediates. Dissolved organic matters exhibit slightly shading effect to the photolysis rates of four parent compounds. However, the ROSs generated by DOM can accelerate the photo-chemical reactions of intermediates, leading to different photo-induced toxicity in present of DOM. According to the detected intermediates and Gaussian calculations, there are different photolysis pathways and mechanisms for the four neonicotinoids. The calculation for photo-sensitization reactions with 3O 2 indicates that both energy transfer reactions and electron transfer reactions can be produced under simulated sunlight radiation, which further consolidate that reactive oxygen species are involved in the photolysis process. A theoretical model has been developed to explain the toxicity variations of four neonicotinoids in different aqueous conditions. [Display omitted] • All the four neonicotinoids exhibit the photo-induced toxicity to V. fischeri , but with different toxic response. • ROSs are involved in and play important roles in the photo-chemical transformation of intermediates. • The amounts of ROSs play key roles in the photo-induced toxicity variation for the four neonicotinoids in different solution. • A developed theoretical equation can well explain the toxicity variations of four neonicotinoids to V. fischeri. [ABSTRACT FROM AUTHOR]

Abstract: Three Fe/TiO2 photocatalysts with different content of Fe (1.9, 7.2 and 13.9%, w/w) were synthesized by a simple deposition–precipitation method and characterized by XRD, SEM, N2 physisorption at 77K and Mössbauer spectroscopy. The characterization showed the presence of nano-sized Fe2O3 particles (less than 4nm) on the TiO2 support. The photocatalytic efficiency of the catalysts was examined on the example of thiacloprid (TCL) degradation under UV light irradiation in aqueous suspension in the presence/absence of H2O2. Since the efficiency of TCL degradation in the presence of H2O2 (heterogeneous photo-Fenton process) was more than two times higher, all other investigations were conducted in the presence of H2O2. The photocatalyst with 7.2%, w/w Fe (denoted as 7.2Fe/TiO2) appeared to be most efficient. The photocatalytic degradation studied under different operating conditions indicated that 0.5gL−1 of 7.2Fe/TiO2 was an optimal catalyst loading, and the optimal pH was 2.8. In the investigated range of initial concentrations of TCL (0.06–0.32mM) the photocatalytic degradation in the first stage of the reaction followed approximately a pseudo-first order kinetics. The suspended Fe/TiO2 spontaneously precipitated once the stirring of the reaction mixture was terminated (>90% after 15min). The results clearly demonstrated that 7.2Fe/TiO2 was stable and resistant to photocorrosion during the photocatalytic degradation of TCL. The higher efficiency of 7.2Fe/TiO2 compared to Degussa P25 under the optimal experimental conditions of TCL photodegradation, spontaneous precipitation of the suspension, possibility of reusing the catalyst, as well as an insignificant increase in the iron concentration in water solution, all this indicates the possibility of the practical application of this photocatalyst for water treatment. [Copyright &y& Elsevier]

Abstract: Although some studies concerning flash photolysis and photocatalytic ozonation of thiacloprid have already been published, no complete investigation and explanation of the effects of thiacloprid photodegradation under the conditions of UV and UV/H2O2 (high-pressure mercury lamp and H2O2) have been reported yet. The photochemical degradation of thiacloprid (0.32mM) was studied under a variety of solution conditions, by varying the initial concentrations of H2O2 from 0 to 162mM and the pH from 2.8 to 9. In the UV/H2O2 system, thiacloprid reacted rapidly, the maximum first-order rate constant (2.7×10−2 min−1, r =0.9996) being observed at the H2O2/thiacloprid molar ratio of 220 and pH 2.8. Under these conditions, 97% of the thiacloprid was removed in about 120min. The thiacloprid degradation is accompanied by the formation of a number of ionic byproducts (Cl−, acetate, formate, , and ) and organic intermediates, so that after 35h of irradiation, 17% of organic carbon remained non-degraded. The application of UV radiation, or H2O2 alone, yielded no significant thiacloprid degradation. The study of the rate of removal of thiacloprid from natural water showed that it is dominantly influenced by the presence of . [Copyright &y& Elsevier]

• Simultaneous determination of two neonicotinoid residues using MIPs. • Excellent extraction of thiamethoxam and thiacloprid from light and dark honey. • Development of UHPLC–MS/MS method for reliable quantification of pesticides. In this work, new selective and sensitive dual-template molecularly imprinted polymer nanoparticles (MIPs) were synthesized and characterized. Sorbent MIPs were investigated for simultaneous extraction and clean-up of thiamethoxam and thiacloprid from light and dark honey samples. In this study, ultra-high-performance liquid chromatography–tandem mass spectrometry triple-quadrupole (UHPLC-MS/MS) (QQQ) was used to detect and quantify the pesticides. The kinetic model with adsorption kinetics of sorbent was investigated. The optimal adsorption conditions were 80 mg of polymer MIPs, a 30-min extraction time, and a pH of 7. The detection limit (LOD) and the quantification limit (LOQ) varied from 0.045 to 0.070 µg kg−1 and from 0.07 to 0.10 µg kg−1, respectively. The intra-day and inter-day precision (RSD, %) ranged from 1.3 to 2.0% and from 8.2 to 12.0%, respectively. The recovery of thiamethoxam and thiacloprid ranged from 96.8 to 106.5% and 95.3 to 104.4%, respectively, in light and dark honey samples. [ABSTRACT FROM AUTHOR]

In this decade, photocatalytic degradation of organic contaminants has attracted great attentions. In this study, we used graphic carbon nitride (g-C 3 N 4) nanosheets as the photocatalyst for the degradation of thiamethoxam (THM). The properties of g-C 3 N 4 nanosheets have been fully characterized by the analysis techniques. The experiments results shown that under the optimum condition, 91.3% of THM degradation efficiency can be reached in the presence of g-C 3 N 4 nanosheets within 60 min under visible light irradiation. Take the realistic application into consideration and to fully investigate the reaction process, the influence of reaction parameters, including the dosage of g-C 3 N 4 nanosheets, initial THM concentration, and initial solution pH value, co-existence ions, humic acid (HA) and fulvic acid (FA) have been systematically studied and discussed. Results demonstrated that weak acidity and neutral condition is benefit for THM decomposition, and Ca2+ and Mg2+ present enhanced inhibition effect than Na+ for THM removal. Meanwhile, PO 4 3- and CO 3 2- show strong inhibition effect, but HA and FA performed weak inhibitory effect. The trapping experiments and electron spin resonance (ESR) measurement demonstrated that superoxide radical (•O 2 -), hydroxyl radical (•OH) and holes (h+) are all generated during the reaction process. There are all participated in the THM decomposition process and •O 2 - plays the major role on it. The results obtained in this study indicated that metal free g-C 3 N 4 present great photocatalytic activity and stability for THM removal and owns great potential in the application of actual agricultural environment. [Display omitted] • Visible light degradation of thiamethoxam based on g-C3N4 has been systematically studied. • Superoxide radical, hydroxyl radical and holes are all contributed to thiamethoxam decomposition. • Environmental factors study demonstrates g-C3N4 owns great stability for thiamethoxam removal. • g-C3N4 has a strong practical significance for thiamethoxam wastewater remediation. [ABSTRACT FROM AUTHOR]

• A double-enzymes-mediated Fe2+/Fe3+ conversion strategy was developed for acetamiprid residue detection (2.66 ng mL−1). • Fe2+ as T 2 signal transformation and amplification can show stable and sensitive signal out-put. • Fe2+, ACh, AChE and CHO are optimized to obtain the best reaction system with one-step mixing assay. • The sensor showed a 335-fold improvement in the sensitivity than that of TEIA method (0.89 μg mL−1). It is a great challenge to develop a newly rapid and accurate detection method for pesticide residues. In this work, based on acetylcholinesterase (AChE) and choline oxidase (CHO), a double-enzymes-mediated Fe2+/Fe3+ conversion as magnetic relaxation switch was explored for the measurement of acetamiprid residue. In the double-enzymes reactions, acetylcholine chloride (ACh) can be catalyzed to produce choline by AChE, which is successively hydrolyzed to betaine and hydrogen peroxide (H 2 O 2) by CHO. According to the enzyme inhibition principle, AChE activity will be inactivated in the presence of acetamiprid, thus leading to the less production of H 2 O 2. Wherein, Fe2+, ACh, AChE and CHO were optimized as the reaction substrates. In the reaction system, acetamiprid can be reflected by the transverse relaxation time (T 2) that related with H 2 O 2 mediated Fe2+ variations, which was further developed as an enzyme cascade amplification method. The detection linear range is 0.01∼1000 μg mL−1 (R2 = 0.99), and the limit of detection (LOD) is 2.66 ng mL−1 (S/N = 3, n = 3), behaving a 335-fold improvement in LOD than that of traditional enzyme inhibition method (0.89 μg mL−1). This method can realize "one-step mixing" detection of acetamiprid, which makes it a promising analytical tool for monitoring pesticide residue in complicated samples. [ABSTRACT FROM AUTHOR]

Neonicotinoid insecticides have been widely used in plant protection against pests worldwide. Generally, more than one neonicotinoids are detected in plants and foods, and such mixtures may show combined toxicity and increase the risk for both insects and higher organisms. In this study, the combined toxicity of imidacloprid (IM), acetamiprid (AC) and thiamethoxam (TH) was investigated using human neuroblastoma cell line (SK-N-SH) and lepidopteran cell line (Sf-9). Results showed that binary and ternary mixtures could enhance the inhibition of growth of both SK-N-SH and Sf-9 cells at low doses. In SK-N-SH cells, based on CompuSyn software analysis, all the mixtures of IM+AC, IM+TH, AC+TH and IM+AC+TH showed synergistic effects at concentrations < 50 mg/L, but IM+AC, IM+TH showed antagonistic effects at higher concentrations. For Sf-9 cells, all mixtures revealed synergistic effects at low concentrations (< 0.1 mg/L) except IM+AC, showing antagonism at higher concentrations (> 0.5 mg/L). The toxicity thresholds of mixtures denoted by BMDL 10 values were all lower than those for single pesticides and the combined BMDL 10 value of AC+TH was the lowest one. It is concluded that the co-occurrence of several neonicotinoid insecticides may enhance their toxicity and aggravate the health risk for both insects and human. Image 1 • Thiamethoxam had the highest toxic potential both on Sf-9 and SK-N-SH cells. • Synergy effects observed from combined treatment at low concentration. • The benchmark dose lower bound of acetamiprid plus thiamethoxam was the lowest one. [ABSTRACT FROM AUTHOR]

This study systematically investigated the advanced oxidation processes driven by the white-rot fungus (WRF) Phanerochaete chrysosporium in the removal of the neonicotinoid pesticide imidacloprid (IMI). The quinone redox cycling driven by P. chrysosporium promotes the degradation of IMI in presence of Mn2+ and Fe (III)-oxalate. Results showed that the degradation efficiency varied with the type of quinine mediator, and gallic acid (GA) was a more effective mediator than 1,4-benzoquinone (BQ). The removal rate of IMI was increased by 1.8-fold in the presence of 100 μM of Mn2+ compared with that of the system without Mn2+. The addition of oxalic acid and EDTA promoted the degradation of IMI, and the effect of oxalic acid was more pronounced at the later stage (day 5 and day 6); the optimal Fe3+/oxalate ratio was 1:3. Time-course experiments revealed the maximum removal rates of IMI were 97.37%, 82.0% and 73.52% at the initial IMI concentration of 10, 20, and 30 mg/L, respectively, in the presence of 100 μM Mn2+, 100 μM Fe3+-300 μM of oxalate and 500 μM gallic acid. Under quinone redox cycling conditions, the good correlation between ·OH production rates and the enzymes activity was concluded, the quinines redox cycles promote enzyme activity, as well as the rate of ·OH production. Results from this study indicated the GA mediator-based system using P. chrysosporium offers a new method to advance the bio-oxidation process owing to its simple culture system, low-cost precursors, unique fungi, and degradation stability. • P. chrysosporium has the ability to drive advanced oxidation processes. • Advanced bio-oxidation by P. chrysosporium increased its degradation ability. • An appropriate amount of Mn2+ is beneficial for IMI degradation. • The substitution of Fe3+-EDTA by Fe3+-oxalate improve IMI degradation rate. • The quinines redox cycles promote enzyme activity. [ABSTRACT FROM AUTHOR]