Search Results (230)

Background/Objectives: Thiamethoxam (TMX) is one of the most extensively utilized insecticides of the neonicotinoid family; however, its application is associated with notable toxic effects on multiple organs of mammals. Our purpose was to explore the potential hepatoprotective effect of taurine (TAU) and/or gallic acid (GA) against TMX-induced liver damage, with an emphasis on their role in regulating SIRT-1/PGC-1α, NF-κB/iNOS, and p53/Bax/caspase-3 pathways. Methods: Rats were assigned to seven groups (n = 6) and gavaged daily for 28 days with saline (control group), TAU at 50 mg/kg, GA at 20 mg/kg, TMX at 78.15 mg/kg, TMX + TAU, TMX + GA, and TMX + TAU + GA. Results: The findings revealed that TAU and/or GA attenuated TMX-induced liver injury, as demonstrated by the restoration of hepatic performance hallmarks and histological structure. TAU and GA mitigated TMX-mediated oxidative stress and boosted the antioxidant defense mechanism by upregulating the transcription levels of SIRT-1, PGC-1α, Nrf2, and HO-1. Moreover, TAU and GA suppressed TMX-associated inflammatory response by increasing IL-10 concentration and lowering the levels of NF-κB, IL-1β, and iNOS; the mRNA levels of NLRP3; and TNF-α immunoexpression. Both compounds, individually or concurrently, exerted an anti-apoptotic effect in TMX-treated rats, evidenced by increased Bcl-2 expression and reduced p53 mRNA level, Bax expression, and caspase-3 concentration. Conclusions: TAU and/or GA may be regarded as promising remedies that can alleviate TMX-induced hepatotoxicity by activating SIRT-1/PGC-1α signaling and abolishing inflammation and apoptosis. Full article

Trichogramma dendrolimi, a key egg parasitoid for lepidopteran pest control, faces potential risks from neonicotinoid insecticides like acetamiprid used in integrated pest management (IPM). This study evaluated acetamiprid’s acute and sublethal toxicity to T. dendrolimi and assessed population-level risks via species sensitivity distribution (SSD). Acute toxicity assays using glass-vial residues revealed a 24 h LC₅₀ of 0.12 mg a.i. L⁻¹ for adults, three orders of magnitude below the maximum field rate (100 mg a.i. L⁻¹). Sublethal exposure (1/2–1/100 LC₅₀) significantly reduced parasitism and emergence rates (NOEC = 2.3 μg a.i. L⁻¹) but did not affect offspring survival. Acetamiprid also shortened offspring development at 11.5–57.5 μg a.i. L⁻¹. SSD analysis identified T. dendrolimi as the most sensitive parasitoid to acetamiprid (HC₅/HC₅₀) = 0.11/5.88 mg a.i. L⁻¹), with field rates (30–100 mg a.i. L⁻¹) indicating a potentially affected fraction (PAF) of 76.8–97.9%. These findings underscore the need to integrate sublethal effects into pesticide regulations to conserve parasitoid-mediated ecosystem services. Full article

Neonicotinoids (NEOs) are a class of systemic insecticides widely used in agriculture owing to their high efficacy and selectivity. As one of the most globally consumed beverages, tea may represent a potential dietary source of pesticide residues. However, limited research has examined NEO contamination in tea and its implications for human exposure, highlighting the need for further investigation. Therefore, this study comprehensively evaluated the residue characteristics, processing effects, and human exposure risks of six NEOs—dinotefuran (DIN), imidacloprid (IMI), acetamiprid (ACE), thiamethoxam (THM), clothianidin (CLO), and thiacloprid (THI)—in Chinese tea products. According to the findings, the primary pollutants, ACE, DIN, and IMI, accounted for 95.65% of the total NEO residues in 137 tea samples, including green, oolong, white, black, dark, and herbal teas. The highest total target NEO (∑₆NEOs) residue level was detected in oolong tea (mean: 57.86 ng/g). Meanwhile, IMI exhibited the highest residue level (78.88 ng/g) in herbal tea due to the absence of high-temperature fixation procedures. Concentrations of DIN in 61 samples (44.5%) exceeded the European Union’s maximum residue limit of 10 ng/g. Health risk assessment indicated that both the chronic hazard quotient (cHQ) and acute hazard quotient (aHQ) for adults and children were below the safety threshold (<1). However, children required special attention, as their exposure risk was 1.28 times higher than that of adults. The distribution of NEO residues was significantly influenced by tea processing techniques, such as full fermentation in black tea. Optimizing processing methods (e.g., using infrared enzyme deactivation) and implementing targeted pesticide application strategies may help mitigate risk. These results provide a scientific foundation for enhancing tea safety regulations and protecting consumer health. Full article

Imidacloprid, a systemic neonicotinoid insecticide, exerts its neurotoxic effects by binding to nicotinic acetylcholine receptors in the central nervous system. In this study, we examined the effects of commercial imidacloprid formulations on the growth of Chlorella vulgaris and other algal species, comparing these responses with those induced by plant hormones. Our results demonstrate that formulated imidacloprid stimulates C. vulgaris growth at concentrations as low as 7.82 μM, with a more pronounced effect than certain phytohormones. We observed similar growth-enhancing effects in other algal species exposed to imidacloprid. Notably, pure imidacloprid induced equivalent growth responses in C. vulgaris, confirming that the observed stimulation results from the active ingredient itself rather than formulation adjuvants. Given its insecticidal mode of action, potential worst-case aquatic contamination scenarios with imidacloprid may lead to significant increases in algal biomass through both direct (growth stimulation) and indirect (reduction of zooplankton grazing pressure) mechanisms. Full article

Drosophila suzukii (Matsumura) is a relevant pest affecting berries and stone fruits globally, including in the Neotropical region, where its invasion was reported about a decade ago. Despite chemical control being the main management method for D. suzukii, data on insecticide susceptibility in Neotropical D. suzukii populations are scarce. Here, we assessed the susceptibility of three field-collected Brazilian D. suzukii populations to four insecticides (i.e., deltamethrin, permethrin, spinetoram, imidacloprid) and contrasted this with a standard insecticide-susceptible population. Using the discriminating concentration (LC₉₀) from the standard susceptible population, we identified resistant populations. Synergist exposure (piperonyl butoxide, triphenyl phosphate, diethyl maleate) indicated the role of detoxification enzymes in resistance. Our results showed that deltamethrin was the most toxic, followed by spinetoram, permethrin, and imidacloprid. While all field populations were similarly susceptible to pyrethroids and spinosyns, one population from Minas Gerais (i.e., Paula Candido) had significantly lower imidacloprid susceptibility, with only 53.4 ± 5.2% mortality at 10.0 g/L (the equivalent of 10-fold the estimated imidacloprid LC₉₀). Only piperonyl butoxide increased the imidacloprid susceptibility of Paula Candido flies. Our findings indicate the occurrence of cytochrome P450 enzyme-based imidacloprid resistance in the state of Minas Gerais, which can challenge the management of D. suzukii in Brazil. Full article

The interactions between dissolved organic matter (DOM) and agrochemicals (e.g., neonicotinoid insecticides, NIs) govern the distribution, migration, and potential environmental risks of agrochemicals. However, the long-term effects of agricultural management on the DOM components and structure, as well as their further influences on the interactions between DOM and agrochemicals, remain unclear. Here, spectroscopic techniques, including Fourier transform infrared spectroscopy, two-dimensional correlation spectroscopy, and three-dimensional excitation–emission matrix fluorescence spectroscopy were employed to delve into the interaction mechanism between the DOM from citrus orchards with distinct cultivation ages (10, 30, and 50 years) and imidacloprid, which is a type of pesticide widely used in agricultural production. The findings revealed that the composition and structure of soil DOM significantly change with increasing cultivation age, characterized by an increase in humic substances and the emergence of new organic components, indicating complex biodegradation and chemical transformation processes of soil organic matter. Imidacloprid primarily interacts with fulvic acid-like fractions of DOM, and its binding affinity decreases with increasing cultivation age. Additionally, the interactions of protein-like fractions with imidacloprid occur after humic-like fractions, suggesting differential binding behaviors among DOM fractions. These results demonstrate that cultivation age significantly influences the composition and structural characteristics of soil DOM in citrus orchards, subsequently affecting its sorption capacity to imidacloprid. This study enhances the understanding of imidacloprid’s environmental behavior and provides theoretical support for the environmental risk management of neonicotinoid pesticides. Full article

Neonicotinoids (NEOs) are widely used neuroactive insecticides with several adverse effects on human health. This study examined 186 colostrum samples collected at three time points between 2007 and 2019 from Shanghai, China to investigate the distribution and temporal variations of NEOs. The median total concentration (ΣNEOs) was 136 ng/L, with the imidacloprid equivalent concentration (IMIeq) of 249 ng/L. N-desmethyl-acetamiprid (DM-ACE) had the highest median level at 49.6 ng/L, accounting for 43.9% of ΣNEOs, followed by imidacloprid (IMI) (20.1 ng/L and 22.1%). Thiamethoxam (THM), clothianidin, and acetamiprid were also identified as important parent compounds (p-NEOs). Temporal variations suggested a decrease in ΣNEOs, IMIeq, and DM-ACE concentrations from 2013 to 2019; however, the total concentrations of p-NEOs remained comparable. Distinct trends were also observed in the concentrations of dinotefuran and IMI. Maternal body mass index and weight changes, which reflect the dietary habits of mothers, appeared to influence IMI and THM levels. No statistically significant relationships were found between colostrum concentrations and birth parameters using full-term birth data in 2019. The estimated hazard quotients (≤0.003), which were far below the risk threshold of 1, generally indicated negligible health risks for breastfeeding neonates. Nevertheless, the substantial contribution from several p-NEOs warrants further investigation. Full article

In integrated pest management (IPM), achieving a balance between biological and chemical control strategies is essential for effective pest control. Therefore, it is crucial to assess the impact of chemical pesticides on natural enemies. Neonicotinoid insecticides, particularly dinotefuran, are among the most widely used insecticides globally. This study investigated the acute toxicity of dinotefuran to adult predatory natural enemy Picromerus lewisi and evaluated its effects on offspring growth and predation. The results showed that the 72 h median lethal concentrations (LC₅₀) of dinotefuran for female and male adults (F₀) were 0.624 mg/L and 0.592 mg/L, respectively. Exposure to LC₅₀ concentrations of dinotefuran significantly reduced parental fecundity, longevity, and offspring growth and predatory ability. The most pronounced effects were observed when both female and male adults were exposed. Specifically, the pre-oviposition period was 2.64 times longer than in the control group, oviposition frequency dropped to 18.6%, total fecundity decreased to 13.4%, and the offspring emergence rate was reduced to 50% of the control group’s level. Furthermore, predation efficacy of F₁ generation (5th instar nymphs and adults) on Spodoptera exigua and Spodoptera litura larvae reduced by 52.76% to 66.81%. Exposure of only female adults also led to significant but less severe effects on offspring, while male-only exposure showed the least impact. These findings highlighted the toxicological risks of dinotefuran to P. lewisi, impairing both reproductive and predatory functions, which could undermine biological control and affect the success of IPM strategies. Full article

The excessive levels of neonicotinoid insecticides, particularly thiacloprid (THI), in the environment have become a significant threat to ecosystems. This study investigates the catalytic degradation of THI using pinewood biochar (PBC), zero-valent iron (ZVI), and ZVI/PBC composite, with a particular focus on the reaction activity modulation mediated by organic acids (humic acid: HA and oxalic acid: OA). Reductive dechlorination dominated THI degradation as observed by Cl⁻ release kinetics. Compared to HA (39.73%), the OA (73.44%) addition markedly increased the THI removal efficiency by ZVI/PBC, which alone has a lower removal efficacy, i.e., 37.29%. The increase in the THI removal rate was attributed to its enhanced electron transfer capacity. As confirmed by electrochemical characterization, the addition of organic acids promotes electron transfer between THI and catalysts (ZVI, PBC, or ZVI/PBC), thereby improving the removal efficiency of THI. XRD/XPS analyses elucidated that OA preferentially converted passivating Fe₂O₃/Fe₃O₄ on ZVI/PBC to reactive FeOOH and formed electron-conductive Fe–COO bonds, thereby suppressing oxide layer formation. PBC amplified these effects through ZVI dispersion and electron shuttling, reducing aggregation-induced activity loss. These findings provide a mechanistic framework for optimizing ligand-engineered iron composites, offering practical strategies to enhance pesticide remediation efficiency in organic acid-rich environmental systems. Full article

Pesticides such as neonicotinoids frequently harm beneficial insect pollinators and affect their survival, social behavior, digestive system, and metabolism. Investigating the mechanisms behind these impairments is crucial for enhancing pesticide risk assessments. Apis cerana, a native honeybee species in Asia, has received limited research attention regarding the toxicological mechanisms of thiamethoxam (TMX) exposure. We exposed newly emerged worker bees of A. cerana to a field-relevant dose of TMX (400 ng/g) under laboratory conditions to examine whether TMX exposure triggers similar or distinct effects in different biological processes and tissues. Our results demonstrate that TMX damages the gut cell structure and significantly increases mortality. Gut transcriptomic analysis revealed that the activation of signaling pathways such as glycosphingolipid biosynthesis, Notch signaling, and Wnt signaling likely contributed to structural damage in gut cells. Head transcriptomic results indicated that the activation of pathways including pyruvate metabolism, glycolysis/gluconeogenesis, thiamine metabolism, and riboflavin metabolism might negatively affect the stability of the neural system in A. cerana. The metabolic dysfunction of glycine, serine, threonine, as well as glycerophospholipids potentially impairs the neural system, leading to behavioral abnormalities and mortality. In summary, field-level TMX damages the gut cell structure, destabilizes the neural system, and increases the mortality rate of A. cerana. These findings demonstrate that TMX exposure induces complex, tissue-specific effects. This study provides a comprehensive understanding of the molecular and physiological impacts of TMX on A. cerana, offering valuable insights for the conservation and protection of this important pollinator species. Full article

Imidacloprid (IMI), a widely used neonicotinoid insecticide, has raised environmental concerns due to its potential impact on non-target aquatic organisms. This study investigates the effects of IMI exposure on the intestinal immune function of red swamp crayfish (Procambarus clarkii, P. clarkii), focusing on oxidative stress, inflammatory response, and autophagy. The P. clarkii was exposed to different doses of IMI (0, 10.93, 21.86, 43.73, 87.45 μg/L) for 96 h. Our findings reveal that IMI exposure leads to a survival rate of less than 70% when the concentration was 87.45 μg/L at 96 h. Hemolymph LZM and AKP contents were significantly decreased at the medium and high concentrations, and the expressions of hsp70 and nf-κb genes were significantly up-regulated. The expression of the lysozyme gene was significantly down-regulated. Additionally, the activities of SOD, CAT, and GPX were significantly decreased, the contents of MDA were significantly increased, and the gene expressions of CuZnsod, mMnsod, cat, and gpx in the gut were significantly down-regulated after exposure to medium-high IMI. The expression of autophagy-related genes showed that the expressions of beclin1, atg5, atg13, and lc3c genes in the medium- and high-concentration groups were significantly up-regulated. In summary, this study elucidates that medium-high levels of IMI exposure impair intestinal immune function in P. clarkii through mechanisms involving oxidative stress, inflammatory response, and autophagy. Full article

The impact of agrochemicals on pollinators, especially honey bees, has drawn significant attention due to its critical implications for worldwide food stability and ecosystems. Given the potential threat of insecticides to honey bees, bees may encounter multiple insecticides simultaneously during foraging. This study investigated the toxic effect of an insecticide mixture (IM) containing acetamiprid (neonicotinoid) and deltamethrin (pyrethroid) on the survival and cognitive appetitive performance of Apis mellifera jemenitica, a vital native pollinator in arid regions of Saudi Arabia. The lethal concentration (LC₅₀) was determined by assessing bees’ mortality rates following exposure to IM through topical and oral routes. Significant bee mortality occurred at 4–48 h post treatment with IM through both exposure routes, showing a trend of increased mortality with higher IM concentrations compared to the control bees. Throughout all tested times, topical exposure proved relatively more effective, resulting in significantly greater bee mortality compared to oral exposure to IM. Food intake declined progressively with rising IM concentrations during oral exposure. The LC₅₀ values of IM at 24 h after treatment were 12.24 ppm for topical and 10.45 ppm for oral exposure. The corresponding LC₁₀, LC₂₀, and LC₃₀ values were 3.75 ppm, 5.63 ppm, and 7.54 ppm for topical exposure and 2.45 ppm, 4.04 ppm, and 5.78 ppm for oral exposure, respectively. The combination index (CI) revealed a synergistic effect (0.43) for topical exposure and antagonistic effects (1.43) for oral exposure, highlighting differential toxicity dynamics. IM exposure significantly impaired cognitive acquisition and memory reinforcement in honey bees, as demonstrated through behavioral assays, indicating potential neurotoxic effects. Learning and memory formation significantly declined at 2, 12, and 24 h after exposure to sublethal concentrations of IM through both topical and oral routes. Thus, evaluating the interactive impact of multiple pesticides on bees’ health and cognitive function is essential, particularly in regions where diverse agrochemicals are routinely utilized. Full article

Neonicotinoid insecticides (NNIs) can harm non-target species. This study examines NNIs’ distribution, sources, human exposure risks, and ecological risks in the Qiantang River’s water and sediment. NNIs concentrations ranged from 8.92 to 88.0 ng/L in water and 0.55 to 16.6 ng/g dw in sediment. The concentrations showed a trend of middle reaches > lower reaches > upper reaches. Agricultural activities were the main NNIs source, followed by wastewater treatment plants. Infants had the highest NNIs intake, with a daily intake of 15.4 ng/kg body weight, about 5.4-times higher than adolescents. Using the species sensitivity distribution and relative potency factor, the acute and chronic toxicity thresholds for aquatic organisms were estimated at HC₅ values of 3636 ng/L and 40 ng/L, respectively. Species at lower trophic levels were more sensitive to NNIs. While acute risks to aquatic fauna are low, prolonged exposure poses potential risks to human and ecological health. These findings contribute to the enhancement of the regulatory framework for NNIs and serve as a reference for policymakers in formulating water pollution management strategies, thereby advancing the sustainable development of water resources in the region. Full article

Imidacloprid, a widely used neonicotinoid insecticide, targets insect pests but also affects natural enemies. However, the effects of neonicotinoid insecticides on closely related insects remain unclear. We evaluated the harmful effects of imidacloprid on the phytophagous Halyomorpha halys and predaceous Arma chinensis. Bioassays revealed that imidacloprid was more toxic to H. halys than to A. chinensis and more harmful to the males than to the females of the two insects. A. chinensis adults recovered from imidacloprid-induced knockdown, as evidenced by restored respiratory rates, metabolic rates, and locomotion. Surviving A. chinensis showed reduced fecundity, suggesting a trade-off between detoxification and reproduction. Bioinformatics analysis of nicotinic acetylcholine receptors (nAChRs) and molecular docking simulations indicated a lower diversity of the nAChR gene family in A. chinensis than in H. halys, with weaker binding to imidacloprid, consistent with the relatively low toxicity of the insecticide in this species. This might account for the susceptibility differences to imidacloprid between the species. These findings underscore the efficacy of imidacloprid against H. halys and provide insights into the toxicities of neonicotinoids to target and non-target insects. Full article

In this study, residues of 10 neonicotinoid insecticides were tested with 143 fresh samples of Oenanthe javanica using the QuEChERS method combined with UPLC-MS/MS. Based on the residue results, the point estimation method was used to assess dietary risks for adults and children, and the cumulative risk was assessed according to the hazard index (HI) and relative potency factor (RPF) methods. The results showed that 71 out of 143 samples of fresh Oenanthe javanica sold in Hainan tested positive for neonicotinoid insecticides, with a detection rate of 49.65%. Six neonicotinoid insecticides were detected and their detection frequencies are as follows: imidacloprid (44.76%), acetamiprid (16.08%), clothianidin (13.29%), dinotefuran (4.90%), thiamethoxam (3.50%) and flonicamid (3.50%). The most frequently co-detected combination was imidacloprid and acetamiprid, with a detection rate of 29.58%. The results of acute and chronic dietary risks showed that all the obtained values of %ADI (acceptable daily intake) and %ARfD (acute reference dose) are far below 100%, so the risks of the six detected neonicotinoid insecticides are acceptable for various population groups. Meanwhile, the results of the cumulative risk showed that all the obtained values of the hazard index and the corrected total exposure concentration are far lower than the health guidelines, indicating that the residue levels of neonicotinoid insecticides in fresh Oenanthe javanica are acceptable. However, it is notable that its acute risk is higher than its chronic risk, and the dietary risk for children is higher than adults. These findings will provide a theoretical basis and objective data for supporting the revision of MRLs for Oenanthe javanica, as well as valuable guidance for the production, consumption, regulation and standardization of Oenanthe javanica sold in Hainan. Full article