Search Results (169)

The contamination of traditional Chinese medicines (TCMs) with neonicotinoid pesticides, notably acetamiprid (ACE), poses a significant challenge to product safety. Conventional detection methods are often hampered by operational complexity, prolonged analysis times, and dependence on sophisticated instrumentation, rendering them impractical for rapid on-site screening. To address these limitations, an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) was developed for the efficient quantification of ACE residue in TCM matrices. A monoclonal antibody-based ic-ELISA was developed through the synthesis of an ACE antigen. Critical assay parameters—including coated antigen concentration, antibody dilution ratio, and blocking buffer composition—were systematically optimized. The validated protocol was subsequently applied to ACE detection in five representative TCMs. The sensitivity (IC₅₀), limit of detection (IC₁₅), and detection range (IC₂₀-IC₈₀) of the developed ic-ELISA for ACE were 13.61 ng/mL, 0.50 ng/mL, and 1.00–150.99 ng/mL, respectively. The ic-ELISA demonstrated good stability and specificity, with cross-reactivity for ACE analogs all below 1.5%. Additionally, the ic-ELISA for ACE achieved recoveries of 86.87–104.80% in spiked TCM samples (Lonicerae Japonicae Flos, Lycii Fructus, Bulbus Lilii, Citri Reticulatae Pericarpium, and Jasminum sambae Flos), with relative standard deviations (RSDs) of 3.33–12.05%. The recovery rate of ic-ELISA was verified to be in good consistency with that of high-performance liquid chromatography (86.09–102.10%), indicating that ic-ELISA has acceptable accuracy and precision. This approach is simple and sensitive, making it suitable for the rapid quantitative detection of ACE residues in TCM products. It also provides technical references for the development of ic-ELISA for other small-molecule contaminants. Full article

Neonicotinoid pesticides, including imidacloprid (IMI), are widely used in agriculture and as household insecticides. IMI displays strong affinity for insect nicotinic acetylcholine receptors (nAChRs); however, neonicotinoids still partially bind to mammalian nAChRs. Relatively little is known about how neonicotinoid exposure alters learning, memory or mood, even though nAChRs play a role in these mechanisms. We tested the hypothesis that developmental exposure to IMI impairs performance on memory tasks, and anxiety- and depressive-like behavior. We orally dosed pregnant CD-1 mice from gestation day 10 to birth with vehicle or IMI at 0.5 mg/kg/day or 5.7 mg/kg/day. When exposed animals were adults, we examined cognitive and emotional behaviors and we examined the effect of IMI on α7 and α4 nAChR subunit mRNA expression using qPCR. For both sexes, IMI exposure was associated with impaired striatal-dependent procedural learning task and hippocampal-dependent spatial learning but had no effect on hippocampal-dependent working memory. Males, but not females, displayed increased anxiety-like behavior, with low dose subjects displaying more pronounced effects, suggesting a non-linear dose response. In males, we found lower α7 subunit mRNA expression in the hippocampus and amygdala and lower α4 mRNA expression in the striatum compared to controls. Thus, exposure to IMI during a critical period is associated with disruptions to cognitive and anxiety-like behaviors. Additionally, in males, IMI exposure is associated with reduced expression of nAChR subunits in relevant brain regions. Full article

Integrated pest management (IPM) in tomato (Solanum lycopersicum L.) on the Ecuadorian coast represents a critical challenge, given that pest persistence has led producers to abandon the crop, generating significant losses. This study compared pest population fluctuations in greenhouse and open field conditions under realistic management conditions and free infestation, considering the influence of environmental factors and applications of biorational, semisynthetic, and synthetic pesticides. In open fields, infestations were high and sustained, exceeding treatment thresholds, while in greenhouses, levels were lower, attributable to the protection of the aphid netting. Product efficacy depended on the pest and the level of infestation: Azadirachta indica, Bacillus thuringiensis, and Beauveria bassiana were effective in low infestations; spinetoram and abamectin reached efficacies between 80 and 100% in moderate infestations; neonicotinoids had variable efficacy, ranging from 47.8% to 89.9%. Since the system determines the type of pest and the level of infestation, monitoring becomes a key tool for timely decision-making. The findings show that the greenhouse limits the entry of the main pest, Prodiplosis longifila. While it does not prevent the presence of smaller pests, such as thrips and white mites, the combination of physical barriers and low-toxicity pesticides significantly reduces populations, minimizing the number of applications and the use of more toxic insecticides. The proposed strategy provides solid evidence for the effective implementation of a greenhouse to reduce pest pressure and promote IPM in protected coastal systems in Ecuador. Full article

The European Union’s goal to reduce pesticide risk, exemplified by restrictions on insecticides like neonicotinoids, necessitates a shift from single-substance risk assessment to a holistic evaluation of pest control strategies. To address this, a novel decision-support grid was developed that integrates 13 environmental, biodiversity, and human health risk indicators for multiple active substances across an entire crop season into a single Final Scenario Score (FSS), ranging from 0 to 1 (where 1 is the risk of the reference scenario). This framework was applied to three case studies in Belgium—sugar beet, apple, and pear cultivation—where neonicotinoid-based reference scenarios were compared with chemical and/or organic alternatives under low (best-case) and high (worst-case) pest pressure conditions. The results highlight the complexity of finding viable alternatives, with an FSS below 0.75 as the justification threshold. In sugar beet, only the best-case chemical alternative (FSS = 0.71) met the threshold, while worst-case chemical alternatives failed due to increased risk. For apple and pear, organic alternatives consistently showed low-risk scores (FSS 0.27–0.61) but faced important efficacy gaps against key insect. Chemical alternatives in orchards were justifiable in low-pressure scenarios (FSS 0.64–0.73) but failed under high pest pressure (FSS 0.91–0.93). This novel decision-support grid proves to be a valuable tool for guiding sustainable pest control strategies for regulators and field advisors. Full article

Pesticides have attracted widespread attention as significant factors affecting aquatic ecosystem diversity. Jiujiang Port, located at the confluence of the Yangtze River and Poyang Lake, is the largest hub port in Jiujiang City and also an important agricultural production area. However, the characteristics and ecological risks of pesticide pollution in this basin have rarely been reported. In this study, we investigated the contamination profiles of 49 typical pesticides in surface waters in the Jiujiang Port area and conducted a multi-level ecological risk assessment using the Risk Quotient (RQ) method, semi-probabilistic risk assessment (RQ_f), and Joint Probability Curve (JPC) approach. The results showed that the average concentrations of triazine, carbamate, neonicotinoid, and organophosphorus pesticides were 3.063 ng·L⁻¹, 0.321 ng·L⁻¹, 3.752 ng·L⁻¹, and 1.554 ng·L⁻¹, respectively. Among them, hexazinone was the most predominant contaminant, with an average concentration of 19.209 ng·L⁻¹. Twenty pesticides were detected at frequencies exceeding 80%, and the overall pollution level was higher in the wet season than in the dry season. The RQ assessment indicated that 11 pesticides posed low or higher risks in either the wet or dry season, with imidacloprid, simazine, and terbutryn presenting moderate risks and hexazinone, chlorpyrifos, and diazinon posing high risks. The RQ_f values of hexazinone, chlorpyrifos, diazinon, imidacloprid, simazine, and terbutryn all exceeded 1 in both seasons, indicating substantial ecological risks to aquatic organisms in the Jiujiang Port basin. The JPC evaluation suggested that hexazinone may pose a moderate risk to 0.3–6% of aquatic species, while chlorpyrifos, imidacloprid, and terbutryn were associated with a low risk. This study elucidates the contamination characteristics, spatiotemporal distribution, and ecological risks of pesticides in surface water, providing a scientific basis for the protection of aquatic biodiversity and the management of pesticide pollution in the Jiujiang Port basin. Full article

Neonicotinoid insecticides (NEOs), one of the most widely used pesticide classes worldwide, have raised concerns due to potential neurotoxic effects. Yet evidence on human exposure and health outcomes, particularly in preschool children, remains limited. In this study, 506 children aged 3–6 years from Shenzhen, China, were assessed. Neurobehavioral development was evaluated with the Strengths and Difficulties Questionnaire (SDQ), and urinary concentrations of 11 NEOs were measured, including imidacloprid (IMI), clothianidin (CLO), thiamethoxam (THM), dinotefuran (DNT), nitenpyram (NIT), sulfoxaflor (SFX), acetamiprid (ACE), thiacloprid (THD), flonicamid (FLO), 6-chloronicotinic acid (6-CINA), N-desmethyl-acetamiprid (NACE), and N-desmethyl-thiamethoxam (NTHM). Seven compounds showed high detection rates, including IMI (97.4%), CLO (100%), THM (100%), DNT (99.8%), NIT (99.8%), NACE (100%), and NTHM (99.8%). The mean urinary concentration was 234.145 μg/g creatinine, exceeding levels in earlier studies and indicating widespread exposure. IMI, NTHM, and NACE showed significant positive dose–response relationships with emotional symptoms, hyperactivity, and total difficulties and were major contributors in mixture models; sex-stratified analyses suggested effect modification for NTHM and NACE. These findings provide new epidemiological evidence to inform public health risk assessment and regulatory action on NEOs. Full article

Honeybees (Apis mellifera ligustica Spin.) are the most significant pollinating insects, playing a vital role in maintaining biodiversity. In healthy colonies, the reproductive success of the queen and the genetic contribution of drones are essential for long-term survival, directly affecting brood production, genetic diversity, and environmental adaptability. While the physiological and behavioral impacts of chemical pesticides on worker bees are relatively well documented, the risks to reproductive bees (queens and drones) remain poorly understood. In this study, we comprehensively assessed the effects of the widely used neonicotinoid thiamethoxam on the key developmental and physiological parameters in reproductive bees, including survival, pupation rate, eclosion rate, hormone titers, and detoxification enzyme activities. Our finding reveals that thiamethoxam exerts sublethal effects on larvae, significantly impairing the fitness of reproductive bees. Specifically, exposure altered juvenile hormone III, ecdysone titer, and acetylcholinesterase activity in reproductive larvae, with these effects showing a negative correlation with pesticide concentration. Notably, CYP450 activity exhibits a biphasic dose–response, with an initial elevation followed by a decline after reaching peak levels. These results demonstrate that thiamethoxam adversely affects the growth and development of reproductive bees, potentially compromising colony stability. By elucidating these sublethal effects, our study provides critical insights for mitigating pesticide-related threats to honeybee health. Our findings may help to scientifically and rationally avoid the potential risks of chemical pesticides to honeybees. Full article

Honeybees (Apis mellifera) are indispensable pollinators vital to global biodiversity, ecosystem stability, and agricultural productivity, and they promote over 35% of food crops and 75% of flowering plants. Yet, they are in unprecedented decline, partly as a result of neonicotinoid pesticide use elsewhere. These effects on honey bee health are synthesized in this paper through molecular, physiological, and behavioral data showing that sublethal effects of neonicotinoids impair honey bee health. As neurotoxic insecticides that target nicotinic acetylcholine receptors (nAChRs), these insecticides interfere with neurotransmission and underlie cognitive impairment, immune suppression, and oxidative stress. Developmental toxicity is manifested in larvae as retarded growth, reduced feeding, and increased death; queen and drone reproduction are impaired, lowering colony viability. As a result, adult bees have shortened lives and erratic foraging, are further disoriented, and experience impaired navigation, communication, and resource collection. Together, these effects cascade to reduced brood care, thermoregulatory failure, and heretofore unrecognized increased susceptibility to pathogens, increasing the probability of colony collapse at the colony level. Contaminants such as pesticides may cause pollinator exposure and, in turn, may cause their population to be undermined if they are not mitigated; therefore, urgent mitigation strategies, including integrated pest management (IPM), regulatory reforms, and adoption of biopesticides, are needed to mitigate pollinator exposure. The focus of this review lies in the ecological necessity of restructuring how agriculture is managed to simultaneously meet food security and the conservation of honeybee health, the linchpin of global ecosystems. Full article

Background: Experimental studies suggest that some insecticides, fungicides, and herbicides can result in liver cell death, but population-based evidence is lacking. We investigated associations between urinary pesticide metabolites and liver biomarkers among adolescents and adults in an Ecuadorian agricultural area. Methods: We examined participants in 2016 (N = 528, 11–17 years) and 2022 (N = 505, 17–24 years). Plasma alanine aminotransferase (ALT), aspartate aminotransferase, soluble cytokeratin-18, and erythrocytic acetylcholinesterase were measured. Urinary biomarkers included four organophosphates, six neonicotinoids, three pyrethroids, two herbicides, and two fungicides. Generalized estimating equation (GEE) models examined associations and introduced sex and age interaction terms and quadratic terms. Quantile g-computation evaluated the effects of pesticide mixtures. Results: No significant associations were observed between pesticide biomarkers and liver biomarkers in longitudinal or cross-sectional analyses. A curvilinear association was found between 3-phenoxybenzoic acid (3-PBA; pyrethroid) and ALT (β_quadratic = −0.35, 95% CI: [−0.67, −0.04]) in 2016, but not in 2022. Sex modified the associations of 3-PBA with AST, ALT, and CK18-M65 in adolescents (2016), with non-significant positive associations observed in males and non-significant negative associations observed in females. No pesticide mixture effects were observed. Conclusions: Urinary biomarkers of various insecticides, herbicides, fungicides, and their mixtures were not associated with liver biomarkers among adolescents and young adults in agricultural settings. These largely null findings, consistent across time points, suggest background-level exposures in these settings possibly do not harm liver health in this population, though effects at higher exposures cannot be ruled out. Full article

Organophosphate pesticides, fungicides, and neonicotinoid insecticides are frequently employed in the cultivation and production of leafy vegetables. The conventional detection methods for these pesticides rely on chromatographic techniques, which are characterized by good precision and sensitivity. Nevertheless, these methods suffer from drawbacks such as complex sample pretreatment, prolonged detection times, and high costs, hindering the realization of on-site detection. This paper introduces a detection method based on surface-enhanced Raman spectroscopy (SERS) for the quantitative and qualitative analysis of pesticide residues in leafy vegetables. Gold nanoparticles (AuNPs) were meticulously synthesized to serve as the substrate for enhancing Raman signals. The average particle size was approximately 50 nm, and a significant absorption peak appeared at 536 nm. The density functional theory (DFT) with the B3LYP/6-311G was utilized to calculate the theoretical Raman spectra of the pesticides. The characteristic Raman peaks of the pesticides were selected as calibration peaks to establish calibration equations relating the concentration of pesticide residues to the intensity of these calibration peaks. By substituting the intensity of the calibration peak corresponding to the lowest detectable limit in the SERS spectra into the calibration equation, the quantitative detection limit was calculated. The study revealed that the detection limit for phosmet residues in Chinese cabbage could be was below 0.5 mg/kg, with an R² of 0.93363, a standard deviation ranging from 3.87% to 8.56%, and recovery rates between 94.67% and 112.89%. For thiabendazole residues in water spinach, the detection limit could be below 1 mg/kg, with an R² of 0.98291, a standard deviation of between 1.71% and 9.29%, and recovery rates ranging from 87.67% to 107.83%. In the case of acetamiprid residues in pakchoi, the detection limit could also be below 1 mg/kg, with an R² of 0.95332, a standard deviation of between 4.00% and 9.10%, and recovery rates ranging from 90.67% to 113.75%. These findings demonstrate that the SERS-based detection method for the semi-quantitative and qualitative analysis of pesticide residues in leafy vegetables is an effective approach, enabling rapid and reliable detection of pesticide residues in leafy vegetables. Full article

The competitive retention of pollutants in water tables determines their environmental fate and guides routes for their removal. To distinguish the fine differences in competitive binding at zeolite adsorption centers, a group of neonicotinoid pesticides is compared, relying on theoretical (energy of adsorption, orientation, charge distribution) and experimental (spectroscopic and thermogravimetric) analyses for quick, inexpensive, and reliable screening. The MOPAC/QuantumEspresso platform was used for theoretical calculation, indicating close adsorption energy values for acetamiprid and imidacloprid (−2.2 eV), with thiamethoxam having a lower binding energy of −1.7 eV. FTIR analysis confirmed hydrogen bonding, among different dipole-dipole interactions, as the dominant adsorption mechanism. Due to their comparable binding energies, when the mixture of all three pesticides is examined, comparative adsorption capacities are evident at low concentrations, owing to the excellent adsorption performance of the FAU zeotype. At higher concentrations, competition for adsorption centers occurs, with the expected thiamethoxam binding being diminished due to the lower bonding energy. The catalytic impact of zeolite on the thermal degradation of pesticides is evidenced through TG analysis, confirming the adsorption capacities found by UV/VIS and HPLC/UV measurements. Detailed analysis of spectroscopic results in conjunction with theoretical calculation, thermal profiles, and UV detection offers a comprehensive understanding of neonicotinoids’ adsorption and can help with the design of future adsorbents. Full article

Over the past years, increasing attention has been drawn to the adverse effects of agricultural pesticide use on pollinators, with honeybees being especially vulnerable. The aim of this study was to evaluate the levels of residues detectable and/or quantifiable of neonicotinoid pesticides and other pesticides in biological materials (bees, bee brood, etc.) and beehive products (honey, pollen, etc.) applied as seed dressings in rapeseed and sunflower plants in two growing seasons (2020–2021) in fields located in three agro-climatic regions in Romania. The study involved the comparative sampling of hive products (honey, pollen, adult bees, and brood) from experimental and control apiaries, followed by pesticide residue analysis in an accredited laboratory (Primoris) using validated chromatographic techniques (LC-MS/MS and GC-MS). Toxicological analyses of 96 samples, including bees, bee brood, honey, and pollen, confirmed the presence of residues in 46 samples, including 10 bee samples, 10 bee brood samples, 18 honey samples, and 8 pollen bread samples. The mean pesticide residue concentrations detected in hive products were 0.032 mg/kg in honey, 0.061 mg/kg in pollen, 0.167 mg/kg in bees, and 0.371 mg/kg in bee brood. The results highlight the exposure of honeybee colonies to multiple sources of pesticide residue contamination, under conditions where legal recommendations for the controlled application of agricultural treatments are not followed. The study provides relevant evidence for strengthening the risk assessment framework and underscores the need for adopting stricter monitoring and regulatory measures to ensure the protection of honeybee colony health. Full article

Pesticide exposure gradients between occupational, para-occupational, and general populations remain poorly characterized in North African agricultural contexts. This study evaluates urinary pesticide levels among farmers, indirectly exposed individuals, and a control group in Morocco’s Fez-Meknes region. A cross-sectional survey measured pesticide concentrations using LC-MS/MS in urine samples collected from 154 adults residing in both rural and urban areas. A questionnaire was used to gather information from participants regarding factors that may elevate the risk of pesticide exposure. The results revealed that farmers exhibited the highest concentrations of pesticides in their urine, including compounds classified as Ia/Ib by the World Health Organization. Indirectly exposed individuals showed moderate levels of contamination, with notable detections such as dichlofluanid (22.13 µg/L), while the control group had residual traces of neonicotinoids, notably imidacloprid (2.05 µg/L). Multivariate analyses revealed several sociodemographic factors significantly associated with increased pesticide exposure. The main risk factors identified included low education, residence in an agricultural area, and the consumption of untreated water (wells/rivers). Conversely, wearing personal protective equipment was associated with reduced urinary concentrations. This study highlights intense occupational exposure among farmers, secondary environmental contamination among residents living near treated areas, and the widespread dispersion of pesticide residues into urban areas. Full article

Neonicotinoids are extensively used in agricultural production, yet increasing evidence highlights their cytotoxic effects on various cell types. Research has demonstrated that these pesticides can significantly impair the viability and function of reproductive, adipose, neural, immune, and epithelial cells. The underlying mechanisms involve metabolic disturbances, mitochondrial dysfunction, and oxidative stress. These cellular effects raise serious concerns about the potential risks neonicotinoids pose to both human health and the environment. Further investigation is essential to fully understand their toxicological impact and to inform safer pesticide regulation and use. 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