Neonicotinoid Pesticides Research Articles

Exposure to neonicotinoid pesticides induces physiological disorders and affects color performance and foraging behavior in goldfish.

We investigated the effects of neonicotinoid pesticides (NEOs) on the spontaneous swimming and foraging behavior, as well as the morphological and physiological changes of goldfish. Most fish reared in thiamethoxam (THM)-sprayed rice fields showed the scales easily peeled off, and increased ascites. Some individuals showed decreased bio-defense activity and low plasma Ca2+. Similar changes were found in the exposure test to THM (1.0 and 20.0 μg/L) and dinotefuran (1.2 and 23.5 μg/L). Next, the effects of a low concentration of THM (1.0 μg/L) on the spontaneous swimming and foraging behavior of fish were examined. Fish exposed to THM for 1 week became restless and had increased the swimming performance, especially under natural light, white LED lighting and blue LED lighting. Goldfish exposed to THM had also increased intake of shiny white beads under green LED illumination. These results indicate that the exposure to NEO, even for a short period and at low levels, not only suppressed bio-defense activities and metabolic abnormalities, but also stress response, the swimming and foraging behavior of the fish are likely to be significantly suffered.

Low-temperature subcritical water dechlorination composites of waste PVC/coal fly ash with powerful sensing activity for chemiluminescent detection of acetamiprid and imidacloprid

Pesticide residues in agricultural products are serious threat to people's health. Real-time monitoring of pesticides residues in the environment and agricultural products posed challenges to sustainable methods with high analytical performance for pesticide detection. Herein, waste PVC/coal fly ash (the mass ratio of PVC and coal fly ash was 4:1) was dechlorinated in subcritical water at low temperature to achieve nearly 100 % dechlorination of PVC and obtain carbon-based composite materials (CM-Fe/Al/Si-dPVC) with strong sening activity. For CM-Fe/Al/Si-dPVC, CFe bonding resulted in strong electron migration, and nano/μm SiO2 and Al2O3 doping in the layered polyene C matrix provided large specific surface area, and silicon hydroxyl created good heterogeneous catalytic interfaces. CM-Fe/Al/Si-dPVC could strongly trigger luminol chemiluminescence (CL) reaction and produce intense CL signals. Neonicotinoid pesticides (acetamiprid and imidacloprid) bonded with CM-Fe/Al/Si-dPVC through coordination chelation and hydrogen bonding, which shielded the catalytic active site and increased the Fermi level of system, thus quenching CL reaction. Inspired by these, a cheap CL assay was constructed for detecting neonicotinoids combinations of acetamiprid and imidacloprid (NICs). The detection limits of NICs were 0.7 ng/L. Satisfactory recoveries were obtained for real agricultural products and environmental samples. The results of life cycle evaluation (LCA) revealed that the strategy had significantly small global warming potential (GWP). This work presented a sustainable method with environmental benefits for the detection of neonicotinoids, and also opened up new way for the recycling of organic solid wastes.

Unveiling the link: Neonicotinoids and elevated cardiometabolic risks in Chinese rural residents–from a prospective cohort study combing mendelian randomization study

PurposeThis study aimed to evaluate the relationships of separate and mixed exposure of neonicotinoids on cardiometabolic risk at baseline and follow-up and its change over 3 years, and further explore whether inflammatory markers levels and platelet traits (PLT) mediate these relationships. MethodsIn this prospective cohort study from the Henan Rural Cohort Study, 2315 participants were involved at baseline, and 1841 participants completed cardiometabolic risk predictors determinations during the 3-year follow-up. Each neonicotinoid pesticide was normalized to imidacloprid (IMIeq) using the relative potency factor approach. Quantile-based g-computation (Qgcomp) regression was used to evaluate the effect of the mixtures of neonicotinoids mediation analysis was employed to explore whether inflammatory markers levels and platelet traits mediated these relationships. A two-sample mendelian randomization (MR) study was further used to causal association. ResultsQgcomp regression revealed a statistically positive relationship between neonicotinoids mixture exposure and cardiometabolic risk score at baseline and follow-up over 3 years. Both neutrophils/monocytes and PLT were mediators in the relationship between IMIeq and cardiometabolic risk score at baseline and follow-up over 3 years. The causal risk effect of pesticide exposure were 2.50 (0.05, 4.95) and 5.24 (1.28, 9.19) for cardiometabolic risk indicators including insulin resistance and triglyceride, respectively. Nevertheless, there was no correlation discovered between pesticide exposure and other markers of cardiometabolic risk. ConclusionNeonicotinoid insecticides exposure was connected to an increased cardiometabolic risk, especially in individuals with T2DM. Furthermore, inflammatory markers and PLT seem to be two vital mediators of these associations. Additionally, genetic evidence on pesticide exposure and cardiometabolic risk still needs to be validated by multiregional and multiethnic GWAS studies.

Interactions of traditional and biodegradable microplastics with neonicotinoid pesticides

Neonicotinoid pesticides (NNPs) and microplastics (MPs) are two emerging contaminants in agricultural environment. However, the interaction between MPs (especially biodegradable plastics) and NNPs is currently unclear. Therefore, taking thiacloprid (THI) as an example of NNPs, this study explores the adsorption-desorption process and mechanism of NNPs on MPs (traditional and biodegradable plastics), and analyzed the main factors affecting the adsorption (pH, salinity and dissolved organic matter). In addition, by using diffusive gradients in thin-films device, this study assessed the impact of MPs on the bioavailability of NNPs in soil. The results showed that the maximum adsorption capacity of polyamide 6 (96.49 μg g−1) for THI was greater than that of poly (butylene adipate co-terephthalate) (88.78 μg g−1). Aging increased the adsorption amount of THI (5.53 %–15.8 %) due to the higher specific surface area and reduced contact angle of MPs, but the adsorption mechanism remained unchanged. The desorption amount of THI from MPs in simulated intestinal fluid is 1.30–1.36 times. The MPs in soil alter the distribution of THI in the soil, increasing the bioavailability of THI while inhibiting its degradation. The results highlighted the significance of examining the combined pollution caused by MPs and NNPs.

Neonicotinoid insecticides in a large-scale agricultural basin system-Use, emission, transportation, and their contributions to the ecological risks in the Pearl River Basin, China

Neonicotinoid pollution has increased rapidly and globally in recent years, posing significant risks to agricultural areas. Quantifying use and emission, transport and fate of these contaminants, and risks is critical for proper management of neonicotinoids in river basin. This study elucidates use and emissions of neonicotinoid pesticides in a typical large-scale agriculture basin of China, the Pearl River Basin, as well as the resulting agricultural non-point source pollution and related ecological risks using market surveys, data analysis, and the Soil and Water Assessment Tool. Neonicotinoid use in the basin was estimated at 1361 t in 2019, of which 83.1 % was used in agriculture. After application, approximately 99.1 t neonicotinoids were transported to the Pearl River, accounting for 7.2 % of the total applied. Estimated aquatic concentrations of neonicotinoids showed three seasonal peaks. Several distinct groups of neonicotinoid chemicals can be observed in the Pearl River, as estimated by the model. An estimated 3.9 % of the neonicotinoids used were transported to the South China Sea. Based on the present risk assessment result, several neonicotinoids posed risks to aquatic organism. Therefore, the use of alternative products and/or reduced use is deemed necessary. This study provides novel insights into the fate and ecological risks of neonicotinoid insecticides in large-scale watersheds, and underscores the need for greater efficiency of use and extensive environmental monitoring.

Exposure to an insecticide formulation alters chemosensory orientation, but not floral scent detection, in buff-tailed bumblebees (Bombus terrestris)

Although pesticide-free techniques have been developed in agriculture, pesticides are still routinely used against weeds, pests, and pathogens worldwide. These agrochemicals pollute the environment and can negatively impact human health, biodiversity and ecosystem services. Acetamiprid, an approved neonicotinoid pesticide in the EU, may exert sub-lethal effects on pollinators and other organisms. However, our knowledge on the scope and severity of such effects is still incomplete. Our experiments focused on the effects of the insecticide formulation Mospilan (active ingredient: 20% acetamiprid) on the peripheral olfactory detection of a synthetic floral blend and foraging behaviour of buff-tailed bumblebee (Bombus terrestris) workers. We found that the applied treatment did not affect the antennal detection of the floral blend; however, it induced alterations in their foraging behaviour. Pesticide-treated individuals started foraging later, and the probability of finding the floral blend was lower than that of the control bumblebees. However, exposed bumblebees found the scent source faster than the controls. These results suggest that acetamiprid-containing Mospilan may disrupt the activity and orientation of foraging bumblebees. We hypothesize that the observed effects of pesticide exposure on foraging behaviour could be mediated through neurophysiological and endocrine mechanisms. We propose that future investigations should clarify whether such sub-lethal effects can affect pollinators’ population dynamics and their ecosystem services.

Method optimization for a simultaneous determination of neonicotinoid, carbamate/thiocarbamate, triazole, organophosphate and pyrethroid pesticides and their metabolites in urine using UPLC-MS/MS

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.

Structural gonadal lesions observed in Japanese quail (Coturnix coturnix japonica) following exposure during puberty to the neonicotinoid pesticide, imidacloprid

Exposure to the neonicotinoid insecticide, imidacloprid (IMI), causes reproductive toxicity in mammals and reptiles. However, reports on the effects of IMI on the gonads in birds are grossly lacking. Therefore, this study investigated the effects of pubertal exposure to IMI on the histology, ultrastructure, as well as the cytoskeletal proteins, desmin, smooth muscle actin and vimentin, of the gonads of Japanese quail (Coturnix coturnix japonica). Quails were randomly divided into four groups at 5 weeks of age. The control group was given only distilled water, whereas, the other three experimental groups, IMI was administered by oral gavage at 1.55, 3.1, and 6.2 mg/kg, twice per week for 4 weeks. Exposure to IMI doses of 3.1 and 6.2 mg/kg caused dose-dependent histopathological changes in the ovary and testis. In the ovary, accumulation of lymphocytes, degenerative changes, and necrosis with granulocyte infiltrations were observed, while in the testis, distorted seminiferous tubules, germ cell sloughing, vacuolisations, apoptotic bodies, autophagosomes, and mitochondrial damage were detected. These changes were accompanied by a decreased number of primary follicles (P ≤ 0.05) in the ovary and a decrease (P ≤ 0.05) in the epithelial height, luminal, and tubular diameters of seminiferous tubules at the two higher dosages. In addition, IMI had a negative effect on the immunostaining intensity of desmin, smooth muscle actin, and vimentin in the ovarian and testicular tissue. In conclusion, exposure to IMI during puberty can lead to a range of histopathological alterations in the gonads of Japanese quails, which may ultimately result in infertility.

Developmental toxicity of the neonicotinoid pesticide clothianidin to the larvae of the crustacean Decapoda, Penaeus vannamei

The developmental toxicity effects of neonicotinoid pesticides such as clothianidin have not been fully explored in agricultural applications. This is particularly noteworthy because such pesticides significantly impact the survival rates of invertebrates, with arthropod larvae being particularly vulnerable. This study aimed to address this research gap by specifically investigating the toxicological effects of clothianidin on the developmental stages of the larvae of the economically important aquaculture species Penaeus vannamei. In these experiments, shrimp eggs were exposed to seawater containing different concentrations of clothianidin beginning at N1, and each phase was observed and analyzed to determine its toxic impact on larval development. These results revealed that clothianidin induces an increase in deformity rates and triggers abnormal cell apoptosis. It also significantly reduced survival rates and markedly decreased body length and heart rate in the later stages of larval development (P3). Transcriptomic analysis revealed disruptions in larval DNA integrity, protein synthesis, and signal transduction caused by clothianidin. To survive prolonged exposure, larvae may attempt to maintain their viability by repairing cell structures and enhancing signal transduction mechanisms. This study offers the first empirical evidence of the toxicity of clothianidin to arthropod larvae, underscoring the impact of environmental pollution on aquatic health.

Occurrence and inhalation health risk of neonicotinoid pesticides in outdoor air particulate matters from 2019 to 2021 in China

Neonicotinoid insecticides (NNIs), as a new type of insecticide, are widely used in agriculture and daily life. Because of the low volatility of NNIs, few studies have evaluated them in atmospheric particulate matter. In this study, 101 outdoor PM2.5 samples were collected from the Wuhan urban area from 2019 to 2021, leading to the detection of seven NNIs and three of their metabolites. The detection frequencies of all 10 substances were more than 60%, with DIN (dinotefuran) and IMI (imidacloprid) reaching 100%. DIN (52.4 pg/m3) and IMI (43.0 pg/m3) had higher median concentrations than other substances. Concentration distributions of the four substances ACE (acetamiprid), DIN, IMI, and 5-OH-IMI (5-Hydro-Imidacloprid) exhibited statistically significant differences (P < 0.05) across the four seasons. Concentration levels of ACE, CLO (clothianidin), and IMI were statistically different between the three years (P < 0.05). The median concentration of imidacloprid-equivalent total neonicotinoids (IMIeq: generated by the relative potency factor method) was 256.1 pg/m3. Finally, the estimated daily intake (EDI) of NNIs via respiration was greater in infants and young children than in the rest of the population, suggesting that infants and young children were more likely to be exposed to the health effects of airborne residual PM2.5.

Role of brain monoamines in acetamiprid-induced anxiety-like behavior

Neonicotinoid (NN) pesticides have been linked to increased brain dysfunction in mammals, such as anxiety-like behavior; this is thought to involve monoamines (MA), neurotransmitters that control behavior, memory, and learning. However, the mechanism by which NNs affect the central nervous system is not fully understood. In this study, we aimed to investigate whether MAs affect NNs-induced anxiety-like behavior. Mice were orally administered acetamiprid (ACE), an NN, at the no observed adverse effect level (NOAEL) of mouse (20 mg/kg body mass) set by the Food Safety Commission of Japan, and the elevated zero-maze (EZM) test was performed 30 min after administration. After behavioral analysis, levels of four MA (dopamine, 3-MT, serotonin, and histamine) in selected brain regions were determined by liquid chromatography mass spectrometry (LC/MS/MS). In the exposed group, a trend toward increased anxiety-like behavior was observed, and at least one MA concentration was significantly increased in each region. Further, significant correlations were found between behavioral test results and hippocampal serotonin and striatal dopamine concentrations, as well as between dopamine and serotonin concentrations, in the exposed group. As anxiety can influence activity in the behavioral tests, the activity of neurons in the raphe nuclei (RN), a brain region greatly involved in anxiety via the serotonergic system, was examined by staining with anti-serotonin antibodies, and increased serotonergic activity was observed. Taken together, these results suggest that ACE regulates MA levels, notably serotonin levels in the hippocampus and that RN plays an important role in ACE-induced anxiety-like behavior.

Precise Control and Prevention Methods for Whitefly in Greenhouse Vegetables

Trialeurodes vaporariorum Westwood (greenhouse whitefly) are worldwide polyphagous pests of economic importance that damage solanaceous vegetables. Neonicotinoid pesticides and parasitoid Encarsia formmosa Gahan are the main management strategies applied worldwide, but precise control methods in greenhouse vegetables need to be developed to reduce the application amounts of pesticides and improve the suppression of whitefly populations. Therefore, we assessed the indoor acute toxicities and risk assessment of neonicotinoids for T. vaporariorum and E. formosa adults and pupae and compared the control effects of E. formosa and neonicotinoid acetamiprid. According to the acute toxicities results, most neonicotinoid insecticides were more toxic to E. formosa than T. vaporariorum, and pupae were much less susceptible than adults of both species. Moreover, acetamiprid had a low risk effect on E. formosa. Sole application of E. formosa and acetamiprid could effectively control T. vaporariorum, but their combined application resulted in antagonistic effects on the control of T. vaporariorum. The results showed that a combined application or sole use of E. formosa could reduce the use of insecticides, slow down the development of insecticide resistance in whiteflies, and improve the efficiency of controlling the growth of whitefly populations in greenhouse vegetable production.

De novo transcriptome analysis of Protohermes xanthodes Navás (Megaloptera: Corydalidae) reveling the effects of sublethal chlorpyrifos on the expression of cholinergic neuronal genes

The insect cholinergic neuron system is the target for various pesticides, including organophosphate, carbamate and neonicotinoid pesticides. In this study, we conducted a de novo transcriptome analysis on the aquatic insect Protohermes xanthodes and identified for the first time presenting sixteen genes encoding cholinergic neuronal proteins (PxanChaT, PxanVAChT, PxanmAChR, PxannAChRs, and PxanAChEs), which are candidates for acetylcholine synthesis, transport, reception and degradation in cholinergic synapse. FPKM analysis revealed that these genes are primarily expressed in head and nerve cord of P. xanthodes larvae, and some of them are also abundant in hindgut, malpighian tubules and tracheae. After exposed to different concentrations of sublethal chlorpyrifos (CPF), expression of these cholinergic neuronal genes are generally increased and then decreased with the increase of CPF concentration, except PxannAChRα9 which is increased in both 4.2 and 8.4 μg/L CPF groups. Short-term (96 h) CPF exposure resulted in significant up-regulation of PxanAChE1 expression in P. xanthodes larvae exposed to 0.42 and 4.2 μg/L CPF concentrations, while PxanAChE2 was up-regulated only in 0.42 μg/L CPF group. After long-term (14 d) CPF exposure, PxanAChE1 expression was down-regulated in 0.168 and 0.42 μg/L CPF groups. PxanAChE2 expression was dramatically decreased in all CPF groups. Moreover, acetylcholinesterase (AChE) activity was significantly decreased across all long-term CPF exposure groups. These results suggested that sublethal exposure to CPF can disrupt the expression of cholinergic neuronal genes in P. xanthodes larvae, and implied that long-term sublethal CPF exposure may cause toxic effects on P. xanthodes larvae by inhibiting AChE activity. Furthermore, identification of cholinergic neuronal genes in P. xanthodes provided candidate molecular markers for study the toxic effects of environmental pollutants on the neuron system of an aquatic predatory insect with ecological importance.

Neonicotinoid exposure increases Varroa destructor (Mesostigmata: Varroidae) mite parasitism severity in honey bee colonies and is not mitigated by increased colony genetic diversity.

Agrochemical exposure is a major contributor to ecological declines worldwide, including the loss of crucial pollinator species. In addition to direct toxicity, field-relevant doses of pesticides can increase species' vulnerabilities to other stressors, including parasites. Experimental field demonstrations of potential interactive effects of pesticides and additional stressors are rare, as are tests of mechanisms via which pollinators tolerate pesticides. Here, we controlled honey bee colony exposure to field-relevant concentrations of 2 neonicotinoid insecticides (clothianidin and thiamethoxam) in pollen and simultaneously manipulated intracolony genetic heterogeneity. We showed that exposure increased rates of Varroa destructor (Anderson and Trueman) parasitism and that while increased genetic heterogeneity overall improved survivability, it did not reduce the negative effect size of neonicotinoid exposure. This study is, to our knowledge, the first experimental field demonstration of how neonicotinoid exposure can increase V. destructor populations in honey bees and also demonstrates that colony genetic diversity cannot mitigate the effects of neonicotinoid pesticides.

Next-generation neonicotinoid: The impact of cycloxaprid on the crustacean decapod Penaeus vannamei

Cycloxaprid, a new neonicotinoid pesticide, poses ecological risks, particularly in aquatic environments, due to its unique action and environmental dispersal. This study investigated the ecotoxicological effects of various concentrations of cycloxaprid on Penaeus vannamei over 28 days. High cycloxaprid levels significantly altered shrimp physiology, as shown by changes in the hepatosomatic index and fattening. Indicators of oxidative stress, such as increased serum hemocyanin, respiratory burst, and nitric oxide, as well as decreased phenol oxidase activity, were observed. Additionally, elevated activities of lactate dehydrogenase, succinate dehydrogenase, and isocitrate dehydrogenase indicated disrupted energy metabolism in the hepatopancreas. Notably, analyses of the nervous system revealed marked disturbances in neural signaling, as evidenced by elevated acetylcholine, octopamine, and acetylcholinesterase levels. Transcriptomic analysis highlighted significant effects on gene expression and metabolic processes in the hepatopancreas and nervous system. This study demonstrated that cycloxaprid disrupts neural signaling and oxidative balance in P. vannamei, potentially affecting its growth, and provides key insights into its biochemical and transcriptomic toxicity in aquatic systems.

Chronic sub-lethal exposure to clothianidin triggers organismal and sub-organismal-level health hazards in a non-target organism, Drosophila melanogaster

Neonicotinoids are among the most widely used systemic pesticides across the world. These chemicals have gathered significant attention for their potential adverse impacts on non-target organisms. Clothianidin is a novel neonicotinoid pesticide, employed globally to control sucking and chewing types of pests. In nature, various non-target organisms can be exposed to this chemical through contaminated food, water, and air. Nonetheless, extensive investigations demonstrating the sub-lethal impacts of clothianidin on non-target entities are limited. Hence, the present study was aimed to unravel the chronic sub-lethal impacts (LC50 0.74 μg/mL) of clothianidin on a non-target organism, Drosophila melanogaster. The study parameters involved multiple tiers of life ranging from organismal level to the sub-cellular level. 1st instar larvae were exposed to the six sub-lethal concentrations viz. 0.05, 0.06, 0.07, 0.08, 0.09, and 0.1 μg/mL of clothianidin till their 3rd larval instar. Investigations involving organismal level have revealed clothianidin-induced significant reduction in the developmental duration, life span, phototaxis, and physical activities of the treated individuals. Interestingly, the tested compound has also altered the compound eye morphology of treated flies. Study was extended to the tissue and cellular levels where reduced cell viability in gut, brain, and fat body was apparent. Additionally, increased ROS production, nuclear disorganization, and higher lipid deposition were evident in gut of exposed individuals. Study was further extended to the sub-cellular level where chronic exposure to clothianidin up-regulated the major oxidative stress markers such as lipid peroxidation, protein carbonylation, HSP-70, SOD, catalase, GSH, and thioredoxin reductase. Furthermore, the activities of detoxifying enzymes such as CYP4501A1 and GST were also altered. Chronic exposure to clothianidin also triggered DNA fragmentation in treated larvae. In essence, results of this multi-level study depict the ROS-mediated toxicity of clothianidin on a non-target organism, D. melanogaster.

Colorimetric and photothermal double-model immunochromatographic assay based on MoS2@Au nanocomposite for high sensitive detection of imidacloprid in food

In this work, a colorimetric and photothermal double-model immunochromatographic assay for the detection of imidacloprid (IMI) was developed using gold nanoparticles (AuNPs) deposited on two-dimensional layered molybdenum disulphide nanosheets (MoS2 NSs). Here, as a signal amplification carrier, the AuNPs on the surface of MoS2 NSs can be well connected with antibody to prepare the photothermal signal probe, this probe has good biocompatibility and high heat conversion efficiency. It is worthing mentioning that the assay realizes the double-mode signal output of semi-quantitative visual detection and quantitative photothermal detection under 808 nm excitation. Under optimal conditions, the limit of detection (LOD) of assay based on photothermal model for IMI was 0.18 μg L-1 and the visual limit of detection (vLOD) of assay based on colorimetric model was 12 μg L-1. The proposed assay has good specificity and other neonicotinoid pesticide analogues have no effect on assay performance. The detection results of this assay were consistent with that of HPLC, indicating the good accuracy of this proposed quantitative detection method. This double-model assay can be used as a promising candidate for sensitive and rapid detection of IMI, which provides a new strategy for real-time monitoring of pesticide residues in food safety test.

Determination of twelve neonicotinoid pesticides in chili using an improved QuEChERS method with UPLC-Q-TOF/MS

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.

Degradation of the neonicotinoid pesticide imidacloprid by electrocoagulation and ultrasound

Imidacloprid is still a widely used neonicotinoid insecticide that is banned in many countries because of the associated environmental risks. Due to the inefficiency of conventional wastewater treatments for pesticide removal, new treatment methods are being investigated. Electrochemical methods, including electrocoagulation (EC), seem to be promising alternatives considering their effectiveness in removing various pollutants from wastewater. The aim of this study was to investigate the effects of electrode material, current density, ultrasound, and operation time on the efficiency of imidacloprid removal from a model solution by EC. The combination of aluminum electrodes and 20 A of applied current for 20 min resulted in total imidacloprid degradation. A simplified energy balance was introduced as a form of process evaluation. Combining ultrasound with EC resulted in 7% to 12% greater efficacy than using only EC.

Enantioselective bioaccumulation and toxicological effects of chiral neonicotinoid sulfoxaflor in rats

Sulfoxaflor is a widely used fourth-generation neonicotinoid pesticide, which has been detected in biological and environmental samples. Sulfoxaflor can potentially be exposed to humans via the food chain, thus understanding its toxic effects and enantioselective bioaccumulation is crucial. In this study, toxicokinetics, bioaccumulation, tissue distribution and enantiomeric profiles of sulfoxaflor in rats were investigated through single oral exposure and 28-days continuous exposure experiment. Sulfoxaflor mainly accumulated in liver and kidney, and the (−)-2R,3R-sulfoxaflor and (−)-2S,3R-sulfoxaflor had higher enrichment than their enantiomers in rats. The toxicological effects were evaluated after 28-days exposure. Slight inflammation in liver and kidney were observed by histopathology. Sphingolipid, amino acid, and vitamin B6 metabolism pathways were significantly disturbed in metabonomics analysis. These toxicities were in compliance with dose-dependent effects. These results improve understanding of enantioselective bioaccumulation and the potential health risk of sulfoxaflor.