Toxicity Potential of Nutraceuticals.

During the past few decades and especially during and after the COVID-19 pandemic, the use of nutraceuticals has become increasingly popular in both humans and animals due to their easy access, cost-effectiveness, and tolerability with a wide margin of safety. While some nutraceuticals are safe, others have an inherent toxic potential. For a large number of nutraceuticals, no toxicity/safety data are available due to a lack of pharmacological/toxicological studies. The safety of some nutraceuticals can be compromised via contamination with toxic plants, metals, mycotoxins, pesticides, fertilizers, drugs of abuse, etc. Knowledge of pharmacokinetic/toxicokinetic studies and biomarkers of exposure, effect, and susceptibility appears to play a pivotal role in the safety and toxicity assessment of nutraceuticals. Interaction studies are essential to determine efficacy, safety, and toxicity when nutraceuticals and therapeutic drugs are used concomitantly or when polypharmacy is involved. This chapter describes various aspects of nutraceuticals, particularly their toxic potential, and the factors that influence their safety.

Eco-friendly chitosan microspheres as a novel one-step sorbent for the rapid purification and determination of pesticides and veterinary drug multi-residues in aquatic products with HPLC-MS/MS.

A modified QuEChERS method was developed to determine multi-class pesticide and veterinary residues in aquatic products. Chitosan microspheres were conveniently synthesized and utilized as the cleanup adsorbent in the QuEChERS procedure, showcasing rapid filtration one-step pretreatment ability for the determination of drug multi-residues in aquatic products. Compared to conventional synthetic sorbents, chitosan microspheres not only have good purification performance, but also have renewable and degradable properties. This novel sorbent worked well in the simultaneous determination of 95 pesticides and veterinary drug residues in aquatic products after being combined with an improved one-step vortex oscillating cleanup method. We achieved recoveries ranging from 64.0% to 115.9% for target drugs in shrimp and fish matrix. The limits of detection and quantification were 0.5-1.0 and 1.0-2.0 µg kg-1, respectively. Notably, hydrocortisone was detected with considerable frequency and concentration in the tested samples, underscoring the necessity for stringent monitoring of this compound in aquatic products.

LC-MS/MS and GC-MS/MS Cross-Checking Analysis Method for 426 Pesticide Residues in Agricultural Products: A Method Validation and Measurement of Uncertainty.

A method was developed to analyze residual pesticides in various vegetables using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS). A method can analyze over 200 individual compounds, selectively separate peaks within 30 min, and meet various criteria such as those by the Codex Alimentarius Commission (CODEX). Most compounds showed recovery rates between 70 and 120%, and a relative standard deviation was within 20%. Measurement uncertainty, considering various influencing factors such as instrument precision, method sensitivity, experimental conditions, sample handling, and analytical procedures, was meticulously calculated. The expanded uncertainties of cross-checking 33 available pesticides ranged from 10.1 to 26.2 µg/kg at a confidence level of approximately 95%. Risk assessment of detected pesticides in agricultural products indicated a safety range of 0.00003-2.87240%. The developed method effectively analyzes diverse compounds simultaneously, contributing to agricultural product safety.

The use of in vitro bioassays and chemical screening to assess the impact of a minimally processed vegetable facility on wastewater quality.

Fruit- and vegetable-processing facilities may contaminate wastewater via contaminants found in the produce and disinfecting chemicals used. These contaminants may include agrochemicals, pesticides, and disinfectants such as chlorine and quaternary ammonium compounds (QACs). Some compounds may exhibit harmful endocrine-disrupting activity. This study investigated the impact of a minimally processed vegetable facility on wastewater quality via in vitro bioassays and chemical screening. Estrogen activity was assessed via a yeast estrogen screen (YES), and (anti-)androgenic and glucocorticoid activities were evaluated via an MDA-kb2 reporter gene assay. The samples were screened via gas and liquid chromatography-tandem mass spectrometry (GC-MS/MS and LC-MS/MS) to identify target compounds, and GC coupled with time-of-flight mass spectrometry (GC-TOFMS) was used for non-targeted screening. Sample complexity and chemical profiles were assessed using GC-TOFMS. Estrogenic activity was detected in 16 samples (n = 24) with an upper limit of 595 ± 37 ng/L estradiol equivalents (EEqs). The final wastewater before discharge had an EEq of 0.23 ng/L, which is within the ecological effect-based trigger value range for the estrogenic activity of wastewater (0.2-0.4 ng/L EEq). Androgenic activity was detected in one sample with a dihydrotestosterone equivalent (DHTEq) value of 10 ± 2.7 ng/L. No antiandrogenic activity was detected. The GC-MS/MS and LC-MS/MS results indicated the presence of multiple pesticides, nonylphenols, triclocarban, and triclosan. Many of these compounds exhibit estrogenic activity, which may explain the positive YES assay findings. These findings showed that wastewater from the facility contained detergents, disinfectants, and pesticides and displayed hormonal activity. Food-processing facilities release large volumes of wastewater, which may affect the quality of the water eventually being discharged into the environment. We recommend expanding conventional water quality monitoring efforts to include additional factors like endocrine activity and disinfectant byproducts.

Assessment of the toxic influence of locally formulated pesticides on hepatic and renal biomarkers in male Wistar rats.

Background: There is growing concern of the potential damage to vital organs after long term exposure to locally formulated pesticides in rural area of Nigeria. This study was designed to assessed the effects of the individual chemical compound and their combination on the kidney and liver of rats' model. Methodology: Fifty-four rats divided into six groups and three sub-groups were exposed to 25, 50 and 75% dose of each of the pesticide's LD50 for 4 h at 3 days interval in an inhalation chamber for 28 days. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total bilirubin (TOT_BIL), creatinine and urea assay showed significant increase at the aforementioned doses in comparison to the control group. The red blood cell counts, hematocrit and hemoglobin concentrations were significantly altered in the rats administered varying doses of the pesticides when compared with the control. Similar result was obtained for the differential white blood cell counts. Histopathological examinations of the liver tissue of rats showed infiltrated sinusoids, traces of karypyknosis, vacuolar degeneration and microvesicular steatosis while that of the renal tissue showed glomeruli atrophy leading to widened Bowman's spaces as well as few shrunken glomeruli and varied level of degenerative tubular changes to tubular necrosis. Conclusion: This study established that individual pesticides and their mixture is toxic to the liver and kidney, as evidenced by the elevated markers of renal and liver functions and distortion of the structure of both organs as revealed by their photomicrographs. Therefore, it is a matter of public health significance to regularly monitor pesticide residues in foods and humans in order to assess the food safety risk and population exposure to pesticides.

An overview on the legacy and risks of Polychlorinated Biphenyls (PCBs) and Organochlorinated Pesticides (OCPs) in the polar regions.

Polychlorinated Biphenyls (PCBs) and Organochlorinated Pesticides (OCPs) are 'trapped' in a variety of environmental media and can therefore undergo further processing by geochemical cycles. By reviewing a wide range of research studies, we present and discuss the main progresses that affect legacy contaminants, such as migration and transformation processes, biological effects assessment across all Arctic media. PCBs and OCPs demonstrated an overall decreasing concentration trend over time in the Arctic. Ecological risk assessment was undertaken by comparison with two standards, suggesting that there was no ecological risk in either soil or sediment. The concentrations of HCB, ΣHCHs, ΣDDTs, chlordane, mirex, and ΣPCBs increased with trophic levels (TLs), showing a significant linear correlation (P < 0.001). The calculated trophic magnification factors (TMFs) values ranged from 0.0004 to 26.63, among which DDTs had the highest value. Future research need to focus on the long-term fate of PCBs and OCPs.

Agricultural pesticides in feathers of the burrowing owl (Athene cunicularia) and its relationship to land-use in the argentinean pampas.

The pampas of South America represent one of the most productive lands for agriculture in the world, and consequently this activity has expanded throughout the region, especially in Argentina. In this context, native fauna faces various risks associated with agriculture, with exposure to pesticides being one of the most dangerous and deadly. Assessing the impact of pesticides on wildlife becomes fundamental and the use of sentinel species emerges as an important tool to monitor environmental health. In this study, we determined pesticide levels in the burrowing owl Athene cunicularia nesting in both rural and urban areas of the argentinean pampas. We used a multiple scale approach to evaluate the influence of land-uses (urban, crops, and grazing fields) at the nesting site on the contaminant load of A. cunicularia individuals, and assessed the potential use of this owl as a sentinel species. From March 2018 to January 2020, A. cunicularia feathers were collected at their nest sites in one urban and two rural areas. These samples were analyzed for the presence of contaminants, including chlorpyrifos and 18 organochlorine pesticides. All the compounds analyzed were detected in A. cunicularia samples. The chlorpyrifos showed the highest frequency of occurrence and concentration, thus denoting the exposure of owls to current-use pesticides. ∑DDTs showed the highest occurrence among organochlorines, followed by ∑HCHs > ∑Endosulfans > ∑Heptachlors > ∑Drins = ∑Chlordanes > methoxychlor. Principal Component Analysis showed that most of the compounds found in A. cunicularia samples showed a positive association with grazing fields, suggesting that exposure to contaminants does not depend on specific habitat use at the local scale, but probably the regional scale. Our results evidenced the exposure of A. cunicularia individuals to past and current-use pesticides in the pampas of Argentina, and indicate that this owl would be useful as a sentinel species.

Assessing the chemical landscape of the Galápagos Marine Reserve.

The Galápagos Archipelago is at the forefront of the Anthropocene, facing intensifying pressures from its growing human footprint and accelerated global connectivity. Despite this, little is currently known of its chemical landscape. This review critically examines the drivers, sources, distribution and fate of oil, plastics, pesticides, persistent organic pollutants and heavy metals in the Galápagos Marine Reserve, identifying pollutant hotspots and evaluating rapid assessment methods and sentinel species that could aid regional monitoring. The cumulative influence of the Galápagos' equatorial position amongst major (and seasonally variable) atmospheric and oceanic circulation patterns, along with its distinctive geophysical and environmental conditions, such as extreme UV radiation and precipitation, likely exacerbates the archipelagos susceptibility to chemicals from both local and continental inputs. Point and diffuse sources identified include wastewater/effluent discharge, agricultural run-off, mismanaged waste, recreational boating, commercial shipping and industrial fishing. Limited spatiotemporal monitoring has hindered the identification of pollution hotspots, except for harbours as aggregates for maritime activities and urban run-off, and eastern-facing coastlines exposed to the Humboldt Current as plastic accumulation zones. Furthermore, the remote nature and vital protected status of the Galápagos National Park has constrained comprehensive assessment of chemical toxicity and its impacts on marine species across the reserve, with studies primarily restricted to Galápagos pinnipeds. Thus, there is currently insufficient knowledge to determine the extent to which the widespread but sporadic presence of chemical contaminants threatens the resilience and adaptive capacity of Galápagos' complex ecosystems, unique biodiversity and interconnected environmental processes. Future efforts are recommended to strengthen environmental monitoring and chemical risk assessment through the utilisation of rapid assessment tools and regional sentinel species, enhancing fundamental understanding of the chemical landscape in this global conservation Hope Spot, as well as the wider implications of the Anthropocene on diverse, dynamic and remote island ecosystems.

Large scale screening and quantification of micropollutants in fish from the coastal waters of Cochin, India: Analytical method development and health risk assessment.

Urban estuarine and coastal water receive several micropollutants through industrial and agricultural influxes. The bioaccumulation of these micropollutants in fish and their entry into the coastal population's food chain raises significant food safety concerns. Hence, a comprehensive analytical method was developed for ultra-trace level quantification of 345 micropollutants in fish. The optimized sample preparation method could extract compounds suitable for both GC-MS/MS and LC-MS/MS analysis simultaneously. The target list of contaminants included 278 agricultural pesticides and also 102 endocrine disruptors covering polyaromatic hydrocarbons, polychlorinated biphenyls, organochlorines, and endocrine-disrupting pesticides. The GC-MS/MS with large volume injection (LVI) technique, and LC-MS/MS operating in MRM mode, achieved an LOQ of <2.00 ng/g for most of the analytes. The extraction strategy involved tri-phase partitioning between water, acidified acetonitrile, and hexane, followed by salting out. Dispersive solid phase cleanup (dSPE) with C18, Z-Sep+, CaCl2, and MgSO4 was able to reduce the matrix influence, and the method achieved satisfactory recovery in the range of 70.0-120.0 % for all the target analytes. The repeatability and reproducibility relative standard deviation values of the measured analytes were <20.0 %, and the Horwitz ratio values were well below 2. The method was used to accurately measure the target micropollutants in fish from the Cochin estuary, the highly urbanized portion of the Vembanad Lake, and an important Ramsar site. At least one or more of the 41 different micropollutants were identified and quantified in about 90.7 % of the 108 samples analyzed. The importance of large-scale screening and trace-level quantification methods in environmental monitoring and risk assessment is underscored by the results. The risk assessment showed a moderate risk of exposure to the nearby coastal population through the food chain.

Optimization and pharmacological evaluation of phytochemical-rich Cuscuta reflexa seed extract for its efficacy against chlorpyrifos-induced hepatotoxicity in murine models.

The popular organophosphorus (OP) compound chlorpyrifos (CP) has recently gained significant attention due to its health risks, particularly among farmers exposed to OP pesticides. This study aimed to evaluate the acute toxicity of Cuscuta reflexa seed extract (CRSE) and its efficacy of mitigating the adverse effects of CP in albino male mice. For acute toxicity analysis, the first group was served as the control group, while the second group was received CRSE (200 mg/kg/bw) on the first day of the 14-day experiment. For hepatotoxicity analysis, the first group was the control group, the second group (vehicle control) received corn oil (CO) (2 mL/kg/bw), the third group was given CP (20 mg/kg/bw) dissolved in corn oil and the fourth group was given CP (20 mg/kg/bw) along-with CRSE (200 mg/kg/bw) orally via gavage once daily for 21 days. The acute toxicity examination revealed no statistically significant differences between the CRSE-treated and control groups in serum biochemical indicators and histopathological analyses of various organs, suggesting that CRSE as safe at a dosage of 200 mg/kg/bw, with an oral LD50 in mice higher than 200 mg/kg. The hepatotoxicity study demonstrated that the CP administration resulted in liver damage and oxidative stress, while CRSE acted as an antioxidant and attenuated the signs of oxidative stress in liver damage. Hence, a promising therapeutic approach for lowering CP hepatotoxicity is co-treatment with CRSE.

Microbial degradation of contaminants of emerging concern: metabolic, genetic and omics insights for enhanced bioremediation.

The perpetual release of natural/synthetic pollutants into the environment poses major risks to ecological balance and human health. Amongst these, contaminants of emerging concern (CECs) are characterized by their recent introduction/detection in various niches, thereby causing significant hazards and necessitating their removal. Pharmaceuticals, plasticizers, cyanotoxins and emerging pesticides are major groups of CECs that are highly toxic and found to occur in various compartments of the biosphere. The sources of these compounds can be multipartite including industrial discharge, improper disposal, excretion of unmetabolized residues, eutrophication etc., while their fate and persistence are determined by factors such as physico-chemical properties, environmental conditions, biodegradability and hydrological factors. The resultant exposure of these compounds to microbiota has imposed a selection pressure and resulted in evolution of metabolic pathways for their biotransformation and/or utilization as sole source of carbon and energy. Such microbial degradation phenotype can be exploited to clean-up CECs from the environment, offering a cost-effective and eco-friendly alternative to abiotic methods of removal, thereby mitigating their toxicity. However, efficient bioprocess development for bioremediation strategies requires extensive understanding of individual components such as pathway gene clusters, proteins/enzymes, metabolites and associated regulatory mechanisms. "Omics" and "Meta-omics" techniques aid in providing crucial insights into the complex interactions and functions of these components as well as microbial community, enabling more effective and targeted bioremediation. Aside from natural isolates, metabolic engineering approaches employ the application of genetic engineering to enhance metabolic diversity and degradation rates. The integration of omics data will further aid in developing systemic-level bioremediation and metabolic engineering strategies, thereby optimising the clean-up process. This review describes bacterial catabolic pathways, genetics, and application of omics and metabolic engineering for bioremediation of four major groups of CECs: pharmaceuticals, plasticizers, cyanotoxins, and emerging pesticides.

Dog swimming and ectoparasiticide water contamination in urban conservation areas: A case study on Hampstead Heath, London.

Widespread occurrence of two ectoparasiticide compounds in the aquatic environment, imidacloprid and fipronil, have prompted concerns about their potential environmental impacts. However, very little focus has been placed on water bodies in urban green spaces used for dog swimming. In this study, occurrence of both substances on Hampstead Heath, London, was compared in ponds with (n = 3) and without dog swimming activity (n = 3), as well as connecting streams above, between, and below these ponds (n = 6). Imidacloprid and fipronil were detected at main swimming points in dog swimming ponds at mean concentrations of 309 ±â€¯104 ng/L and 32 ±â€¯13 ng/L, respectively, indicating a high environmental risk in all samples. Measured concentrations in ponds not accessible for dog swimming were either below the limits of detection or limits of quantification for both chemicals. Across all ponds, there was a strong positive correlation between measured dog swimming activities and concentrations of imidacloprid (R2 = 0.91) and fipronil (R2 = 0.79). Some contamination was detected in connecting streams between ponds. A wider chemical analysis for the presence of urban waste water chemical residue signatures indicated minimal contamination, including in source waters. A survey of visitors who allow their dogs to swim in the sampled ponds confirmed frequent use of products containing imidacloprid and fipronil. In total, 86 % of 101 dog owners were unaware of the potential environmental impacts of products, and 94 % indicated that protecting nature would be an important consideration when selecting products. Besides the current practice of limiting dog access to ponds, information collected on product use and dog swimming practices identified additional opportunities to reduce contamination. We suggest that more cooperation between industry, regulators, veterinarians, green space managers, and the public can reduce risks to urban biodiversity while maintaining recreational benefits for dog owners and dogs.

Fluorescent Ionic Liquid Aggregates: A Self-Assembled Approach for Pesticide Detection and Catalysis.

The unregulated use of pesticides, industrial discharge of heavy metals, waste, and agricultural runoff may contaminate surface water and groundwater, consequently threatening ecosystems and human health. Thus, the sensitive detection and degradation of pesticides are essential for safety. In this context, herein, we have developed benzimidazolium-based fluorescent surfactant assemblies TA-1/SDS and TA-2/SDBS, which exhibit aggregation-induced emission enhancement in an aqueous medium. The aggregates (TA-1/SDS and TA-2/SDBS) displayed a turn-on emission response upon interaction with carbendazim and azamethiphos with limits of detection 7.5 and 7.8 nM, respectively. The FE-SEM and AFM studies revealed that TA-1/SDS and TA-2/SDBS undergo self-assembly with the addition of AZA and CBZ, resulting in the formation of dendritic structures. In addition to the quantification of AZA and CBZ, TA-1/SDS and TA-2/SDBS have also been evaluated to degrade both pesticides and validated using 31P NMR spectroscopy and LC-MS spectrometry.

Characterization of pesticide exposures and their associations with asthma morbidity in a predominantly low-income urban pediatric cohort in Baltimore City.

BACKGROUND: Pesticides may impact respiratory health, yet evidence of their impact on pediatric asthma morbidity is limited, particularly among urban children. OBJECTIVE: To characterize pesticide biomarker concentrations and evaluate their associations with pediatric asthma morbidity among predominantly low-income, Black children in Baltimore City, USA. METHODS: We measured urinary concentrations of 10 biomarkers for pyrethroid insecticides (cyfluthrin:4F-3PBA, permethrin:3PBA), organophosphate insecticides (chlorpyrifos:TCPY, malathion:MDA, parathion:PNP, diazinon:IMPY), and herbicides (glyphosate:AMPA, GPS; 2,4-dicholorphenoxyacetic acid:2,4-D; 2,4,5-tricholorphenoxyacetic acid:2,4,5-T) among 148 children (5-17 years) with established asthma. Urine samples and asthma morbidity measures (asthma symptoms, healthcare utilization, lung function and inflammation) were collected every three months for a year. Generalized estimating equations were used to examine associations between pesticide biomarker concentrations and asthma morbidity measures, controlling for age, sex, race, caregiver education, season, and environmental tobacco smoke. In sensitivity analyses, we assessed the robustness of our results after accounting for environmental co-exposures. RESULTS: Frequently detected (≥90% detection) pesticide biomarker concentrations (IMPY, 3PBA, PNP, TCPY, AMPA, GPS) varied considerably within children over the follow-up period (intraclass correlation coefficients: 0.1-0.2). Consistent positive significant associations were observed between the chlorpyrifos biomarker, TCPY, and asthma symptoms. Urinary concentrations of TCPY were associated with increased odds of coughing, wheezing, or chest tightness (adjusted Odds Ratio, aOR, TCPY:1.60, 95% Confidence Interval, CI:1.17-2.18). Urinary concentrations of TCPY were also associated with maximal symptom days (aOR:1.38, CI:1.02-1.86), exercise-related symptoms (aOR:1.63, CI:1.09-2.44), and hospitalizations for asthma (aOR:2.84, CI:1.08-7.43). We did not observe consistent evidence of associations between the pesticide exposures assessed and lung function or inflammation measures. CONCLUSION: Among predominantly Black children with asthma, we found evidence that chlorpyrifos is associated with asthma morbidity. Further research is needed to assess the contribution of pesticide exposures to pediatric respiratory health and characterize exposure sources among vulnerable populations to inform targeted interventions against potentially harmful pesticide exposures.

Screening and quantification of pesticides in wetland water, ice, sediment and soil: occurrence, transport and risk assessment.

Current researches on pesticides in wetlands are limited in terms of screening and quantification of many types of pesticides. Understanding the spatial and temporal dynamics, distribution patterns, and environmental risks of pesticides in multiple media is important for wetland ecological conservation. In this study, 222 pesticides were determined in multimedia samples collected simultaneously from the Songhua Wetland during four seasons. Concentrations of target pesticides in water, ice, sediment and soil ranged from 94.1-7445 ng/L, 62.6-953 ng/L, 0.82-50.2 ng/g dw, and 4.32-146 ng/g dw. Large spatial differences (p < 0.05) in pesticide concentrations in ice were found. However, there were no significant differences in the spatial and temporal distribution of pesticides in water, sediment, and soil (p > 0.05), suggesting that there were no correlation between the spatial and temporal use of pesticides. The dynamic exchange of pesticides between water-ice indicated that most pesticides were more enriched in water. However, there were still some pesticides (Dichlorvos and Biphenyl) that showed a stronger tendency to transfer from water to ice. Sediment-water exchange suggested that sediment is a source of secondary releases of most pesticides in wetland ecology, but is a sink for Biphenyl and Oxadiazon. The correlation between concentration ratios and fugacity fraction supported this finding. Most individual pesticides in wetland water and ice had shown low or moderate ecological risk conducted using risk quotient. The cumulative toxic effects of multiple pesticides had a high potential to pose a threat to wetland aquatic organisms.

Impact of pesticides exposure and type 2 diabetes risk: a systematic review and meta-analysis.

OBJECTIVE: We conducted a systematic review and meta-analysis of observational studies that assessed the relationship between pesticides exposure and type 2 diabetes. We also examined the presence of heterogeneity and biases across the available studies. METHODS: We conducted a comprehensive literature search of peer-reviewed studies published from 2011 to 2023, without language limitations. A random-effects model was employed to calculate the overall odds ratio (OR) and its corresponding 95% confidence interval (CI). RESULTS: We included 19 studies (n = 12 case-control and n = 7 cross-sectional) for a total of 45,813 participants in our analysis. Our findings revealed a notable correlation between pesticide exposure and type 2 diabetes (non-specific definition) when not limiting pesticide types (OR: 1.19, 95% CI: 1.11-1.28). Subgroup analysis identified associations between pyrethroid (OR: 1.17, 95% CI: 1.05-1.30) and type 2 diabetes, as well as between organochlorine (OR: 1.26, 95% CI: 1.11-1.43) and type 2 diabetes. However, no statistically significant association was observed between herbicide exposure and the onset of type 2 diabetes (OR: 1.26, 95% CI: 0.91-1.75). In the elderly group, pesticide exposure significantly heightened the risk of type 2 diabetes (OR: 1.25, 95% CI: 1.14-1.38), with no statistically significant heterogeneity among studies (I2 = 14.2%, p = 0.323). CONCLUSIONS: Pesticide (organochlorine and pyrethroid) exposure constitutes a risk factor for type 2 diabetes.

Microplastic ingestion and co-exposure to Nosema ceranae and flupyradifurone reduce the survival of honey bees (Apis mellifera L.).

Bees are exposed to several threats, including pathogens (i.e. Nosema ceranae), pesticides and environmental contaminants. The new insecticide flupyradifurone, and the microplastics in the environment, have raised significant concerns on bee health. This study evaluated the simultaneous effects of microplastics, flupyradifurone, and N. ceranae on honey bee health, focusing on survival rates, N. ceranae replication, daily food consumption, and bee midgut histological alterations. Results showed a significant decrease in bee longevity across all treatments compared to the control, with the combination of flupyradifurone, microplastics, and N. ceranae having the most severe impact. Microplastics and flupyradifurone exposure also increased N. ceranae proliferation, especially in bees subjected to both stressors. Histological analysis revealed reduced regenerative cell nests in the midgut and changes in the nuclear matrix, indicating stress responses. Overall, the simultaneous presence of both biotic and abiotic stressors in nature can synergistically interact, leading to harmful effects on bees.

Respiratory and allergic outcomes among farmworkers exposed to pesticides in Costa Rica.

AIM: We examined the association of exposure to a pesticide mixture with respiratory and allergic outcomes among farmworkers from Costa Rica. METHODS: We conducted a cross-sectional study of 299 farmworkers between May and August 2016. We collected information on sociodemographic factors, pesticide use, and the presence of respiratory and allergic symptoms during the last 12 months via questionnaire. We calculated specific gravity-adjusted average concentrations of 15 pesticide biomarkers measured in urine samples collected during two visits (4-5 weeks apart). We fitted "traditional" Bayesian and Bayesian Weighted Quantile Sum (BWQS) regression models to assess the association of exposure to independent and summed pesticide mixture components with the outcomes of interest. We adjusted all models for age and smoking status. RESULTS: In "traditional" Bayesian analyses, higher urinary concentrations of 2-isopropyl-4-methyl-6-hydroxypyrimidine (IMPY, metabolite of organophosphate insecticide diazinon) were associated with increased odds of a higher asthma symptom score [adjusted OR per two-fold increase in concentrations = 1.15; 95 % credible interval (CrI): 1.04, 1.27)], asthma symptoms or medication use (aOR = 1.37; 95 % CrI: 1.13, 1.67), and rhinitis (aOR = 1.34; 95 % CrI: 1.15, 1.56). Higher urinary concentrations of boscalid-5-hydroxy (metabolite of fungicide boscalid) were associated with increased odds of asthma symptoms or medication use (aOR = 1.24; 95 % CrI: 1.00, 1.55), whereas higher concentrations of 4-hydroxypyrimethanil (metabolite of the fungicide pyrimethanil) were associated with increased odds of eczema (aOR = 1.11; 95 % CrI: 0.99, 1.24). Several inverse associations of herbicide concentrations with respiratory and allergic outcomes were observed. In BWQS analyses, a positive association was found between exposure to the pesticide mixture and increased odds of rhinitis (aOR = 1.96; 95 % CrI: 1.14, 3.20), with IMPY being the largest contributor. CONCLUSION: Our findings indicate that exposure to pesticides may have both independent and summed mixture effects on respiratory and allergic health among farmworkers.

Structure-based virtual screening of novel chitin synthase inhibitors for the control of Phytophthora sojae.

BACKGROUND: Chitin synthase (CHS) is an important target for pesticide development as chitin biosynthesis is essential for the survival and reproduction of various organisms, such as oomycetes, fungi and insects. Small-molecule inhibitors of CHS have potential applications for the control of agricultural pests and diseases. RESULTS: In this study, exploiting the cryo-EM structures of PsChs1, the CHS indispensable to the sporangial production and virulence of soybean root rot pathogenic oomycete Phytophthora sojae, a virtual screening method combining by molecular docking, inhibitory activity measurement and biological activity determination was conducted, to identify novel small-molecule inhibitors of CHS. A chemical library containing ≈1.8 million compounds was screened, and four potent inhibitors (HS-20, HS-24, HS-36 and HS-40) were identified. Amongst these compounds, HS-20 showed the most potent inhibitory activity with a Ki value of 4.2 ± 0.2 µM. Besides inhibitory activities towards PsChs1, these compounds were effective in decreasing sporangial production and preventing zoospore infection. When inoculated with zoospores, HS-20 and HS-24 completely inhibited the growth of P. sojae, suggesting their potential in its prevention and control. CONCLUSION: This study identified four new compounds with potent chitin synthase (CHS) inhibitory activity, all of which significantly reduce sporangia production and zoospore infection. It also presents promising in silico techniques and small molecule candidates for the design and development of novel CHS inhibitors. © 2024 Society of Chemical Industry. Published by John Wiley & Sons Ltd.

Self-Assembly-Activated Engineered Magnetic Biohybrids Loaded with Phosphotriesterase for Sustainable Decontamination and Detection of Organophosphorus Pesticides.

Phosphotriesterase (PTE) biodegradation of organophosphorus pesticides (OPs) is an efficient and environmentally friendly method. However, the instability and nonreusability of free PTE become the key factors restricting its practical application. In this study, a novel cross-linked magnetic hybrid nanoflower (CLMNF) was prepared. Molecular dynamics (MD) simulations were performed to further investigate the enhanced catalytic efficiency of the enzymes. The recovery rate of enzyme activity was 298% due to the large specific surface area and metal ion activation effect. More importantly, the immobilization scheme greatly improved the stability and reuse performance of the catalyst and simplified the recovery operation. CLMNFs retained 90.32% relative activity after 5 consecutive cycles and maintained 84.8% relative activity after 30 days at 25 °C. It has a good practical application prospect in the degradation and detection of OPs. Consequently, the immobilized enzyme as a biocatalyst has the characteristics of high efficiency, stability, safety, and easy separation, establishing the key step in a biodetoxification system to control organophosphorus contamination in food and the environment.