Search Results (413)

A comprehensive ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed for the simultaneous quantification of 50 pesticide biomarkers across nine current-use chemical classes in human urine. These classes include organophosphorus insecticides (which encompass dialkyl phosphates and specific metabolites), pyrethroid insecticides, fungicides, neonicotinoid insecticides, herbicides, insect repellents, organochlorine pesticide metabolites, and plant growth regulators. The method employs solid-phase extraction (SPE) for sample preparation, requiring only 0.2 mL of urine. Chromatographic separation was optimized using a Hypersil Gold AQ column, achieving a total run time of 18 min. Mass spectrometric detection utilized polarity switching in electrospray ionization mode with multiple reaction monitoring. Method validation demonstrated satisfactory linearity (R² > 0.99), high sensitivity with limits of detection ranging from 0.01 to 0.88 ng/mL, and extraction efficiencies between 85% and 113%. Precision and accuracy were within acceptable ranges, with relative standard deviations generally below 15%. The method’s robustness was confirmed through participation in external quality assessment schemes. Application to real samples revealed significant inter-individual variability in pesticide biomarker concentrations, with total measured biomarker levels ranging from 89 to 1242 ng/mL across the 10 individuals analyzed. This method offers comprehensive coverage of current-use pesticide chemical classes, including 30 biomarkers from the U.S. National Health and Nutrition Examination Survey (NHANES) biomonitoring program, and demonstrates improved sensitivity and broader analyte coverage compared to existing methods. The developed assay provides a valuable tool for large-scale biomonitoring studies and environmental health research. Full article

Brazil hosts the world’s greatest stingless bee diversity but remains a leading pesticide consumer. This study evaluated the effects of thiamethoxam on Melipona scutellaris (Apidae) and Scaptotrigona postica (Apidae) larvae using standardized in vitro protocols and patented biomimetic technologies. Larvae were exposed to a field-realistic dose (RD) of 0.02292 ng a.i./larva—calculated using the BeeRex model for citrus crops—and two lower doses: RD/10 and RD/100. Thiamethoxam exposure resulted in significant mortality and developmental alterations, even at 100-fold dilutions. In M. scutellaris, mortality was dose-dependent; RD and RD/10 induced body malformation and reduced food consumption, resulting in >98% mortality. At RD/100, surviving individuals showed significant reductions in body size. In S. postica, all tested doses induced larval darkening and accelerated fungal growth, leading to 100% mortality during the feeding period, including at RD/100. This pattern contrasts with the greater tolerance reported for the adult stage of this species. Overall, the results suggest that larval stages may be more sensitive to thiamethoxam exposure than adults, highlighting the importance of considering different life stages in pesticide risk assessment. These findings also emphasize the need for validated experimental approaches to support environmental risk evaluation for Neotropical pollinators. Full article

Despite the undisputable ecosystem importance of honeybees, human activities have a substantial impact on their health. Since foraging is directly linked to a wide range of crops and bee-attracting flowers, plant protection products are at the forefront of chemical scrutiny, along with contamination of pollen, nectar, beehive components and water by other xenobiotics. In this study, a non-targeted Liquid Chromatography-High-Resolution Mass Spectrometry (LC-HRMS) screening was applied to 25 honeybee samples collected after reported death incidents in Greece. This approach led to the tentative annotation of over 50 compounds across various chemical classes, including pesticides, PFAS candidates not included in the EFSA “PFAS-4”, pharmaceuticals, antibiotics, industrial chemicals, and natural product constituents. In parallel, targeted pesticide residue analysis using liquid and gas chromatography coupled to tandem mass spectrometry (LC-MS/MS and GC-MS/MS) was performed, covering more than 250 active substances and providing direct quantitative results, revealing 11 active substances in concentrations ranging from <limit of quantification (LOQ) to 0.95 mg/kg, overlapping substantially with the HRMS detection. Overall, this study does not allow concrete causal attribution of mortality to specific chemicals; however, it documents complex co-occurrence patterns (pesticides together with other xenobiotics and plant bioactives), not excluding sublethal and mixture-toxicity effects. Quantified pesticide concentrations were below acute LD50-based thresholds, yet selected samples combined neonicotinoid/pyrethroid/fungicide signatures and other contaminants, supporting the need for mixture-toxicity frameworks and effect-based follow-ups. Full article

Neonicotinoids are widely used pesticides that have caused a catastrophic decrease in bee and bumblebee populations worldwide. In addition to insects, neonicotinoids induce toxic effects in other species, including lizards, birds, and mammals. Previous studies have shown that gestational exposure to thiacloprid promotes transgenerational effects in the testes and thyroid. In this project, we described the epigenetic effects of thiacloprid on prostate tissue in directly exposed F1 and non-directly exposed F3 outbred Swiss male mice. We used paraffin sections for morphological analysis and frozen tissue for immunofluorescence analysis, RT–qPCR, and protein analysis. We purified histones and analyzed them through Western blot. We used ChIP–qPCR for histone H3K4me3 occupancy analysis. A tendency to increase in epithelial hyperplasia in F1 but not in F3 prostate was detected. Elevated levels of phosphorylated histone H3 at serine 10, a marker of mitosis, in both the F1 and F3 prostates were noted. A significant increase in the level of the Ki-67 marker of proliferation was detected in the F1 but not in the F3 anterior prostate. Hox gene expression was upregulated in the F1 and downregulated in the F3 prostate. The changes in gene expression were positively associated with histone H3K4me3 alterations at the promoters of the Hoxa and Hoxb13 genes. We determined that regions of Hox genes that play important roles in prostate development had altered DNA methylation in the sperm of F1 and F3. These alterations in DNA methylation were negatively related to gene expression. This is an observational study, as it was part of our previous research on the effects of thiacloprid on the testis and thyroid. Our analysis revealed that gestational exposure to thiacloprid induced an increase in cell proliferation in the prostates of directly exposed F1. Some persistent epigenetic alterations in the prostate of F3 males were not associated with phenotypic changes. Full article

Cyantraniliprole, a second-generation diamide insecticide, exhibits broad-spectrum efficacy against numerous insect pests due to its selective activation of insect ryanodine receptors (RyRs). This activation triggers uncontrolled calcium release from the sarcoplasmic reticulum, resulting in sustained muscle contraction, paralysis, and ultimately death. Its unique mode of action, which is different from that of organophosphates, carbamates, pyrethroids, and neonicotinoids, helps minimize cross-resistance, making it a valuable component of integrated pest management (IPM). However, continuous field use has led to the development of resistance, primarily mediated by target-site mutations within the RyR transmembrane domain (e.g., G4946E, I4743M, and I4790K) and by enhanced metabolic detoxification via cytochrome P450 monooxygenases, carboxylesterases, and glutathione S-transferases. These mechanisms often confer cross-resistance to other diamide insecticides, thereby complicating resistance management. Moreover, sublethal exposures can disrupt insect growth, development, and reproduction, potentially accelerating resistance evolution. In addition, cyantraniliprole poses ecological risks due to its toxicity to non-target organisms such as aquatic species, including zebrafish and water fleas, pollinators such as honeybees, and soil fauna, as well as the environmental persistence of its major metabolite, J9Z38. This review comprehensively integrated current knowledge on the molecular mechanisms of action, genetic and metabolic bases of resistance, sublethal effects, and ecotoxicological impacts of cyantraniliprole, along with its environmental fate, plant uptake and translocation, and residue dynamics in agricultural systems. Finally, we discuss potential risk-mitigation strategies, including formulation optimization, application-method improvements, and resistance monitoring. Overall, this review aims to provide a comprehensive scientific foundation for the sustainable use, resistance management, and regulatory assessment of this widely used insecticide. Full article

The extensive utilization of TMX, a substance characterized by its high toxicity towards honeybees, has exerted a deleterious influence on the employment of neonicotinoid insecticides and the proliferation of bee colonies. However, there is a lack of effective solutions to mitigate the toxicological impact of neonicotinoid insecticides on bees. The present study proposes a method of using MB to alleviate TMX poisoning in honeybee (Apis mellifera ligustica) larvae. The results demonstrated that when bee larvae ingested MB at a concentration of 0.32 mg·L⁻¹, the mortality rate of larvae could be reduced from 47.2% to 25.0%. Transcriptome analysis identified the honeybee dihydrolipoyl dehydrogenase (AmDld) gene as one of the main genes involved in the function of MB. AmDld was highly expressed in larval hemolymph. Its expression levels and enzymatic content were suppressed by either TMX or MB alone but restored by the TMX+MB combination. RNAi-mediated knockdown of AmDld decreased AmDld content and increased larval mortality under the TMX+MB co-treatment from 25.0% to 40.6%. This indicated that the TMX+MB combination rescued AmDld levels, thereby alleviating TMX toxicity to bee larvae. The present study has demonstrated that the ingestion of MB by honeybee larvae has the capacity to reduce the toxicity of TMX, a toxic substance, through the action of the AmDld gene. This provides a novel approach to mitigating pesticide poisoning in bees. Full article

Clothianidin (CLO) is a widely used neonicotinoid insecticide in agricultural systems and may pose risks to non-target aquatic organisms, including amphibians. Here, we evaluated acute and sublethal effects of CLO on Fejervarya cancrivora tadpoles, an important predator of insect pests in rice paddy ecosystems. Acute toxicity tests (96 h) yielded an LC₅₀ of 50.41 mg a.i./L (with LC₁₀, LC₂₅ and LC₃₀ values of 15.35, 31.96 and 36.07 mg a.i./L, respectively). Sublethal exposure at these concentrations significantly reduced body weight, whole-body length, and hindlimb length during metamorphosis. CLO also altered thyroid hormone regulation, with T4 showing a dose-dependent increase, while T3 was elevated relative to controls but showed comparatively limited additional sensitivity to concentration and exposure duration. Locomotor activity was impaired under sublethal CLO exposure, reflected by reduced swimming distance and speed. In addition, frogs that developed from CLO-exposed tadpoles exhibited decreased feeding efficiency on brown planthoppers (Nilaparvata lugens) across developmental stages 46–48. Together, these findings demonstrate that CLO can affect amphibian development, endocrine regulation, and behavior at sublethal levels, highlighting the need to incorporate sublethal endpoints into ecological risk assessment and to promote pest management strategies that reduce impacts on biodiversity and ecosystem services. Full article

Neonicotinoids (NEOs) are among the most widely used insecticides worldwide, and their increasing detection in environmental and human matrices has raised concerns about chronic exposure and potential health risks. However, human data on target-organ burdens and liver–blood partitioning of NEOs remain unclear. Here, we quantified nine NEOs in paired liver tissue and whole-blood samples from 234 individuals to characterize internal distribution patterns and liver–blood partitioning of NEOs in humans. Samples included both liver cancer patients and non-liver cancer individuals, enabling exploratory evaluation of disease-related differences. At least one NEO was detected in 84.6% of blood samples and 87.2% of liver samples, with median concentrations ranging from 0.15–3.52 ng/mL in blood and 0.39–10.99 ng/g in liver, respectively. Dinotefuran was the most abundant compound in both matrices, accounting for 43.9% of total NEOs in blood and 25.8% in liver, indicating substantial matrix-specific compositional differences. Blood-to-liver partition ratios (R_B/L) varied substantially among compounds and showed a significant inverse association with logKow (p = 0.026), suggesting physicochemical property-dependent partitioning. R_B/L values were generally lower in liver cancer patients, indicating a relative shift toward hepatic accumulation. In exploratory logistic regression analyses, hepatic concentrations of acetamiprid, dinotefuran, imidaclothiz, and thiamethoxam remained statistically associated with liver cancer status after adjustment for covariates. Overall, these findings highlight the importance of tissue-specific biomonitoring and internal partitioning for interpreting human exposure to NEOs and for reducing exposure misclassification when evaluating liver-related health outcomes. Full article

Corn is a critically important agricultural crop, with different parts consumed at specific growth stages—notably, fresh corn and corn grain. The field residue behaviors of clothianidin and phoxim in fresh corn and corn grain were investigated by using a QuEChERS technique combined with UPLC-MS/MS, and the dietary exposure risks of the insecticides were evaluated. Field trials were conducted under the recommended application conditions (2250 g active ingredient per hectare of 2% clothianidin and phoxim granules, applied once) at 12 agricultural regions across China under various climatic conditions to study the residue levels of pesticides. The samples were collected at harvest of fresh corn and corn grain, separately. The results indicated that the residues of the phoxim remained stable in all samples stored at −20 °C for 6 months (180 days). At harvest, the concentrations of clothianidin in fresh corn ranged from <0.01 to 0.027 mg/kg (below the MRL of 0.1 mg/kg established by Japan); the concentrations of phoxim in fresh corn were all below 0.01 mg/kg (below the Chinese MRL of 0.1 mg/kg). In corn grain, clothianidin residues ranged from <0.01 to 0.018 mg/kg (below the Chinese MRL of 0.02 mg/kg), while phoxim residues were below 0.01 mg/kg (below the Chinese MRL of 0.1 mg/kg). Dietary risk assessment based on Chinese pesticide registration status and the per capita dietary structure of Chinese residents showed that the national estimated daily intake (NEDI) of clothianidin for the general population was 0.49 mg, accounting for 7.8% of the adult acceptable daily intake (ADI), while NEDI of phoxim for the general population was 0.048 mg, accounting for 19.2% of adult ADI. The results suggest that the associated health risks are acceptable for the general population. On the basis of these findings, it is recommended to establish an MRL for clothianidin in fresh corn in China at 0.1 mg/kg. This study provided basic data on the use and safety of clothianidin and phoxim in fresh corn and corn grain to help the Chinese government formulate a maximum residue level for clothianidin in fresh corn. Full article

Zeugodacus tau (Walker) is a major invasive pest that targets cucurbitaceous plants and other economically significant crops, causing substantial yield and quality losses. The pest’s method of infesting the fruit, however, limits the efficacy of conventional chemical control strategies. This study comprehensively evaluates the insecticidal efficacy of seven insecticides from two key classes—macrolides and neonicotinoids—against various developmental stages of Z. tau. Additionally, it investigates the distribution and degradation patterns of pesticide residues on sponge gourd. Laboratory toxicity tests showed notable differences in sensitivity among the three pest stages. Larvae were the most sensitive to insecticides, followed by adults, with eggs being relatively resistant. Four macrolide insecticides showed high activity against both adults and larvae, while three neonicotinoids displayed low activity against eggs, larvae, and adults of Z. tau. Field residue trials using common recommended dosages demonstrated rapid degradation of pesticide residues on sponge gourd, with residue levels dropping below the national maximum residue limits (MRLs) within 2 to 24 h after application. Further results indicated that pesticide residues accumulated mainly on the peel, with low or undetectable levels in the flesh. Among the macrolide insecticides, residues were nearly undetectable, whereas neonicotinoids, due to their systemic nature, sometimes showed trace residues in the fruit flesh. Oviposition hole measurements revealed an average depth of 0.57 ± 0.29 cm, just beneath the skin, with the hole’s structure effectively protecting the eggs laid by females. Based on the comprehensive analysis of insecticide toxicity and residue degradation, control strategies should primarily target adults. Macrolide insecticides, which have low residue risks and high efficacy against both adults and larvae, are recommended as the preferred option for management. This study, considering the unique damage characteristics of Z. tau, offers valuable insights into chemical control strategies, focusing on insecticide sensitivity at different life stages, residue distribution, and degradation, providing important references for the scientific use of pesticides and the optimization of pest management approaches. Full article

Neonicotinoid insecticides and fluoroquinolone antibiotics frequently co-occur in aquatic and terrestrial environments, posing a threat to human health, yet their combined neurotoxic potential remains poorly characterized. This study aimed to assess the cytotoxicity of typical neonicotinoids and fluoroquinolones as well as their mixtures in human neuroblastoma SK-N-SH cells and identify affected pathways. SK-N-SH cells were exposed to clothianidin (CLO), imidacloprid (IMI), enrofloxacin (ENR), and ofloxacin (OFX) individually and in fixed-ratio mixtures (50% of each compound’s IC₅₀) for 24 h and 48 h, and cell viability was quantified using the alamarBlue^® method. Single-compound dose–response testing showed time-dependent cytotoxicity, with higher potency for fluoroquinolones (24 h IC₅₀: ENR 1.446 mM, OFX 2.742 mM; 48 h IC₅₀: ENR 0.826 mM, OFX 2.005 mM) than neonicotinoids (24 h IC₅₀: IMI 4.754 mM, CLO 5.356 mM; 48 h IC₅₀: IMI 3.631 mM, CLO 4.029 mM). Concentration-addition analysis indicated that most mixtures produced synergistic interaction in reduction in cell viability, with ENR+OFX showing the strongest effect at 48 h (Observed viability 7.138% vs. Predicated viability 82.368%). RNA-seq (24 h) revealed that binary mixtures generally induced more differentially expressed genes than single exposures, and ENR-containing mixtures showed the largest transcriptomic shifts, enriching pathways related to cellular stress and injury as well as neuronal signaling and connectivity. RT-qPCR validated the changes in expressions of five key neurobiology-relevant genes (LMO3, NOS1, ADCY8, FGF7 and TNFRSF12A). These findings highlight the importance of assessing insecticide–antibiotic mixtures when evaluating their hazards in environment. Full article

Insecticide resistance in Aedes aegypti (Linnaeus, 1762), the primary vector of several arboviruses, threatens vector control efficacy and motivates evaluation of current and candidate public health insecticides, such as imidacloprid and broflanilide, and their molecular impacts. Here, we used RNA sequencing (RNA-seq) to characterize the transcriptomic response to one-hour acute exposure to an operational partial-mortality concentration (<50%) of imidacloprid and broflanilide in two Ae. aegypti strains: a field-derived, pyrethroid-resistant population from San Nicolás and a susceptible laboratory strain (New Orleans). Adults were exposed for 1 h to partial-mortality concentration (<50%) doses of each insecticide or acetone control, and differential gene expression and Gene Ontology (GO) enrichment were assessed with DESeq2-based workflows. We detected pronounced baseline transcriptomic differences between strains and extensive activation of gene expression after insecticide exposure, with a strong bias toward up-regulation. A shared transcriptional core involving proteolysis, transmembrane transport, detoxification pathways, and structural remodeling of the cuticle and cytoskeleton was identified across contrasts. Despite these common elements, broflanilide elicited largely conserved early responses between strains, whereas imidacloprid amplified pre-existing divergence and produced marked population-specific transcriptional signatures. These findings suggest greater transcriptional changes in the field-derived strain, particularly in response to imidacloprid, and highlight the importance of integrating population-specific molecular information when designing insecticide rotation schemes and resistance management strategies targeting Ae. aegypti. Full article

Neonicotinoid pesticides are persistent in aquatic environments, posing ecological risks. To address the limited removal efficiency of conventional soil infiltration systems, this study developed an electrochemically enhanced modular ecological infiltration system (MEIS) integrating iron–carbon micro-electrolysis to synergistically remove conventional pollutants (COD, NH₃-N, TN, TP) and two typical neonicotinoids (NNs): imidacloprid (IMI) and imidaclothiz (IMIZ). Under optimized hydraulic loading (1.2 m³/(m²·d)), C/N ratio (3:1), and current density (0.016 mA/cm²), the system achieved high removal efficiencies for conventional pollutants (COD > 99%, NH₃ N 99.8%, TN 81.7%, TP 85.4%). Notably, electrochemical enhancement significantly improved the removal of IMI and IMIZ to 78.1% and 69.1%, respectively, outperforming the non-electrified control. Adsorption kinetics indicated that the filler designed for autotrophic denitrification exhibited the highest adsorption capacity for both pesticides, with a chemisorption-dominated mechanism. Electrochemical enhancement likely enhanced the performance of MEIS by facilitating the release of anodic Fe²⁺ and the generation of reactive species, thereby achieving higher removal efficiencies for conventional pollutants and pesticides. This study presents an efficient and promising ecological technology for the treatment of pesticide-contaminated water, demonstrating strong initial performance and offering substantial potential for further optimization in terms of long-term stability. Full article

Apis mellifera L. is an important pollinator of both wild and domesticated crop plants, thus greatly contributing to plant biodiversity and commercial agriculture. However, in field conditions, honey bees remain exposed to different pesticides which ultimately affect colony health parameters and their associated ecological services. In the current study, the individual toxicities of sub-lethal doses of two distinct insecticides (bifenthrin and acetamiprid) belonging to different groups (pyrethroid and neonicotinoid) were assessed against the foraging activity, social interactions, and longevity of A. mellifera. The bees were exposed to individual doses of both insecticides via the dietary trophic route through contaminated pollen and nectar under natural field conditions. Sunflower crop (Hysun-33) was sown at nine different sites with an isolation distance of 3 km, and was treated with different doses (1/2, 1/4, 1/10, and 1/20 of the recommended field doses) of both insecticides. However, the untreated control crop plots were not subjected to any chemical treatments (bee colonies received no insecticide, and served as the baseline for making comparison). Twenty-seven bee colonies were introduced in these sites after seven days of treatment applications. Significant differences were observed in the foraging activity of A. mellifera (including bees going out from the hive, returning foragers, and those carrying pollens). The fecundity, adult longevity, and social behaviors like trophallaxis and antennation were significantly lower in bees exposed to higher individual insecticidal concentrations. However, the hatching duration, larval duration, and pupal duration were not affected by the tested insecticidal treatments. Overall, these findings demonstrate that the dietary trophic exposure of sub-lethal doses of insecticides compromised colony activities, which is indeed a matter of concern regarding the existing pesticide application methods in different agro-ecosystems. Such impacts may ultimately impair the survival of colonies, particularly when bees remain exposed to these chemicals over an extended period of time. Therefore, future studies must consider the pesticide application techniques and their application timing to mitigate the direct and indirect negative impacts of pesticides on pollinators. Full article

Neonicotinoids are synthetic nicotine-like compounds extensively used globally as insecticides for agricultural and urban purposes. Neonicotinoid-contaminated produce is a major public health concern worldwide. Limited epidemiological studies have shown an association of neonicotinoid exposure with abnormal semen analysis. This study aimed to elucidate the potential disruption of the androgen receptor (AR) by eight common neonicotinoids, including imidacloprid (IMI), acetamiprid, clothianidin, thiamethoxam, dinotefuran, thiacloprid (THI), nitenpyram, and nithiazine using docking and molecular dynamics (MD) simulation. The results showed good binding strength of all compounds (except THI) with AR, as indicated by high binding energy, high binding affinity, and number of bonding interactions. The results of MD simulation supported the conformational stability and structural dynamic behavior of the AR-IMI (receptor-neonicotinoid) complex upon binding. This was indicated by root mean square deviation showing stability of the complex; the root mean square fluctuation showing minimized residual fluctuations upon binding; the radius of gyration showing greater compactness of the protein structure; the solvent-accessible surface area showing no changes upon binding; and the Gibbs funnel energy of the landscape showing a stable conformation state with minimum energy and slight change in size and position of the sampled energy basin of the AR, with a stable equilibrium. Taken together, the structural dynamics results showed that neonicotinoids are bound stably in the same ligand-binding domain of the AR as the native ligand testosterone. This may perturb the natural binding of testosterone with the AR and potentially disrupt downstream signaling and biological pathways, leading to male reproductive dysfunction. Full article