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.

Resolving Coffee Waste and Water Pollution-A Study on KOH-Activated Coffee Grounds for Organophosphorus Xenobiotics Remediation.

This study investigates using KOH-activated coffee grounds (KACGs) as an effective adsorbent for removing organophosphorus xenobiotics malathion and chlorpyrifos from water. Malathion and chlorpyrifos, widely used as pesticides, pose significant health risks due to their neurotoxic effects and environmental persistence. Spent coffee grounds, abundant biowaste from coffee production, are chemically activated with KOH to enhance their adsorptive capacity without thermal treatment. This offers a sustainable solution for biowaste management and water remediation. Adsorption kinetics indicating rapid initial adsorption with high affinity were observed, particularly for chlorpyrifos. Isotherm studies confirmed favorable adsorption conditions, with higher maximum adsorption capacities for chlorpyrifos compared to malathion (15.0 ± 0.1 mg g-1 for malathion and 22.3 ± 0.1 mg g-1 for chlorpyrifos), highlighting its potential in mitigating water pollution. Thermodynamic analysis suggested the adsorption process was spontaneous but with the opposite behavior for the investigated pesticides. Malathion interacts with KACGs via dipole-dipole and dispersion forces, while chlorpyrifos through π-π stacking with aromatic groups. The reduction in neurotoxic risks associated with pesticide exposure is also shown, indicating that no more toxic products were formed during the remediation. This research contributes to sustainable development goals by repurposing biowaste and addressing water pollution challenges through innovative adsorbent materials.

Effect of Chrysin and Chrysin Nanocrystals on Chlorpyrifos-Induced Dysfunction of the Hypothalamic-Pituitary-Testicular Axis in Rats.

AIMS AND BACKGROUND: The escalating global concerns regarding reproductive health underscore the urgency of investigating the impact of environmental pollutants on fertility. This study aims to focus on Chlorpyrifos (CPF), a widely-used organophosphate insecticide, and explores its adverse influence on the hypothalamic-pituitary-testicular axis in Wistar male rats. This study explores the potential protective effects of chrysin nanocrystal (CHN), a flavonoid with known antioxidant and anti-inflammatory properties, against CPF-induced impairments in male Wistar rats. METHODS: Chrysin nanocrystals were prepared using a solvent precipitation method. Six sets of male Wistar rats were subjected to 30 days of treatment, comprising a control group, a group treated solely with CPF, groups treated with CHN at doses of 5 mg/kg and 10 mg/kg, and groups co-treated with CPF and CHN. Serum levels of reproductive hormones, enzyme biomarkers of testicular function, oxidative stress, and inflammatory biomarkers were assessed. Additionally, histological examinations were conducted on the hypothalamus, testes, and epididymis. RESULTS: CHN exhibited antioxidant and anti-inflammatory properties, effectively counteracting CPF-induced reductions in Luteinizing Hormone (LH), serum testosterone, Follicle-Stimulating Hormone (FSH), and testicular enzyme biomarkers. Moreover, CHN enhanced antioxidant defenses, as evidenced by decreased malondialdehyde (MDA) and increased glutathione (GSH) levels in the hypothalamus, and testes, epididymis. Inflammatory markers, including nitric oxide (NO), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α), were significantly reduced in CHN co-treated groups compared to the CPF-only group. Histopathological analyses confirmed the protective effects of CHN on tissue integrity. CONCLUSION: Chrysin nanocrystal demonstrated promising potential in mitigating CPF-induced reproductive deficits in male rats through its anti-inflammatory and antioxidant properties. This study provides valuable insights into therapeutic interventions against environmental toxin-induced reproductive toxicity, emphasizing the potential of chrysin nanocrystals as a protective agent in the context of CPF exposure.

Protective Effects of Curcumin against Nephrotoxicity in Male Rats after Chronic Exposure to Chlorpyrifos.

BACKGROUND: Organophosphorus insecticides, widely used in farming and agriculture, have been associated with various health issues. Curcumin, a natural antioxidant, has shown potential in mitigating the adverse effects induced by these insecticides. AIM: This study aimed to evaluate the nephroprotective effects of Curcumin (CUR) against Chlorpyrifos (CPF)-induced renal damage. METHOD: Forty male Wistar albino rats were randomly assigned to five groups, each containing eight rats: control (0.5 mL of olive oil, the solvent for chlorpyrifos), CPF (10 mg/kg of chlorpyrifos), CPF + CUR 25 mg/kg/day, CPF + CUR 50 mg/kg/day, and CPF + CUR 100 mg/k/day. All groups were treated for 90 days. Finally, kidney tissue was assessed for oxidative stress, inflammatory markers, and histopathological changes. RESULT: A considerable elevation in urea and Creatinine (Cr) concentrations was observed in the CPF group compared to the control rats (p < 0.01). CUR decreased creatinine and urea levels in the CPF-exposed group compared to the non-CUR-treated animals (p < 0.05). Additionally, the concentrations of NO, MDA, IL-6, IL-1ß, and TNFα were significantly increased in the kidneys of the CPF-induced rats compared to the controls (p < 0.001). However, CUR (100 mg/kg) administration significantly reduced the abovementioned parameters in rat kidneys (p < 0.01). CUR (100 mg/kg) also increased superoxide dismutase activity and glutathione concentration in the kidneys of CPF-exposed animals compared to non-CUR-treated rats (p < 0.05). Histopathological analysis revealed severe congestion in the kidney tissue after CPF exposure. However, coadministration of CUR restored the normal structure of the kidney in the experimental rats. CONCLUSION: Our findings suggest that curcumin, a potent antioxidant, can help alleviate chlorpyrifos-induced nephrotoxicity.

Overexpression of Two Odorant Binding Proteins Confers Chlorpyrifos Resistance in the Green Peach Aphid Myzus persicae.

The green peach aphid, Myzus persicae, is a worldwide agricultural pest. Chlorpyrifos has been widely used to control M. persicae for decades, thus leading to a high resistance to chlorpyrifos. Recent studies have found that insect odorant binding proteins (OBPs) play essential roles in insecticide resistance. However, the potential resistance mechanism underlying the cross-link between aphid OBPs and chlorpyrifos remains unclear. In this study, two OBPs (MperOBP3 and MperOBP7) were found overexpressed in M. persicae chlorpyrifos-resistant strains (CRR) compared to chlorpyrifos-sensitive strains (CSS); furthermore, chlorpyrifos can significantly induce the expression of both OBPs. An in vitro binding assay indicated that both OBPs strongly bind with chlorpyrifos; an in vivo RNAi and toxicity bioassay confirmed silencing either of the two OBPs can increase the susceptibility of aphids to chlorpyrifos, suggesting that overexpression of MperOBP3 and MperOBP7 contributes to the development of resistance of M. persicae to chlorpyrifos. Our findings provide novel insights into insect OBPs-mediated resistance mechanisms.

Synergetic studies on the thermochemical activation and polyaniline integration on the adsorption properties of natural coal for chlorpyrifos pesticide: steric and energetic studies.

Three types of synthetic coal-derived adsorbents were characterized as potential enhanced structurers during the removal of chlorpyrifos pesticide. The raw coal (CA) was activated into porous graphitic carbon (AC), and both CA and AC were blended with polyaniline polymers (PANI/CA and PANI/AC) forming two advanced composites. The adsorption performances of the modified structures in comparison with CA were evaluated based on both the steric and energetic parameters of the applied advanced isotherm model (the monolayer model of one energy). The uptake performances reflected higher capacities for the PANI hybridized form (235.8 mg/g (PANI/CA) and 309.75 mg/g (PANI/AC) as compared to AC (156.9 mg/g) and raw coal (135.8 mg/g). This signifies the impact of activation step and PANI blending on the surface and textural properties of coal. The steric investigation determined the saturation of the coal surface with extra active sites after the activation step (Nm(AC) = 62.05 mg/g) and the PANI integration (Nm(PANI/CA) = 113.5 mg/g and Nm(PANI/AC) = 169.7 mg/g) as compared to raw coal (Nm(CA) = 39.6 mg/g). This illustrated the reported uptake efficiencies of the modified samples, which can be attributed to the enhancement in the surface area and the incorporation of additional chemical groups. The results also reflect that each site can be loaded with 3-4 molecules of chlorpyrifos, which are arranged vertically and adsorbed by multi-molecular mechanisms. The energetic studies (< 40 kJ/mol) suggested the physical uptake of pesticide molecules by dipole bonding and hydrogen bonding processes. The thermodynamic functions donate the exothermic properties of 47reactions that occur spontaneously.

Expression reduction and a variant of a P450 gene mediate chlorpyrifos resistance in Tetranychus urticae Koch.

INTRODUCTION: Understanding how insects and mites develop resistance to chlorpyrifos is crucial for effective field management. Although extensive research has demonstrated that T. urticae exhibits high resistance to chlorpyrifos, the specific resistance mechanism remains elusive. Investigating this mechanism could provide valuable insights for pest control strategies. OBJECTIVES: This study aimed to reveal the mechanism of chlorpyrifos resistance in T. urticae. METHODS: The expression level of the CYP392D8 gene in T. urticae strains were analyzed using real- time quantitative PCR and western blot techniques. Functional validation of CYP392D8 was conducted through RNAi and heterogeneous expression. The production of chlorpyrifos-oxon in both resistant and susceptible strains were quantified using LC-MS/MS. Furthermore, the metabolic capabilities of CYP392D8 variants were verified using HPLC-MS and molecular docking. RESULTS: The results showed the expression of CYP392D8 was reduced in some Chinese resistant populations and mites with knocked down CYP392D8 showed decreased susceptibility to chlorpyrifos. Chlorpyrifos-oxon, the active metabolite of chlorpyrifos, was generated when chlorpyrifos was incubated with recombinant CYP392D8 protein in vitro. And a higher efficiency of chlorpyrifos-oxon formation was observed with the CYP392D8-S variant from susceptible mites compared to the CYP392D8-R variant from resistant mites. After treatment with low doses of chlorpyrifos, susceptible mite extracts produced substantial amounts of chlorpyrifos-oxon, while resistant mites only showed trace amounts. In addition, molecular docking studies showed that CYP392D8-S had a higher binding capacity to chlorpyrifos than the CYP392D8-R variant. CONCLUSION: This study reveals a mechanism of insecticide resistance due to the bioactivation reduction in combination with the sequence variation in a pest mite. These findings provide an important theoretical bias for management strategies of mites in the field and comprehensive control.

Organophosphate pesticide chlorpyrifos and its metabolite 3,5,6-trichloropyridinol downregulate the expression of genes essential for spermatogenesis in caprine testes.

Organophosphate pesticides have potent endocrine disrupting effects, hence banned in many countries. However, many organophosphates like chlorpyrifos, malathion et cetera continue to be used in some countries (Wolejko et al., 2022; Wolejko et al., 2022)including India. Fodder mediated ingestion of these substances may be harmful for livestock fertility. We have investigated the effect of the widely used organophosphate pesticide chlorpyrifos (CPF) and its metabolite, 3,5,6-trichloropyridinol (TCPy) on the expression of genes essential for spermatogenesis in goat testicular tissue. The testicular Sertoli cells (Sc) regulate germ cell division and differentiation under the influence of follicle stimulating hormone (FSH) and testosterone (T). Impaired FSH and T mediated signalling in Sc can compromise spermatogenesis leading to sub-fertility/infertility. As Sc express receptors (R) for FSH and T, they are highly susceptible to the endocrine disrupting effects of pesticides affecting fertility by dysregulating the functioning of Sc. Our results indicated that exposure to different concentrations of CPF and TCPy can compromise Sc function by downregulating the expression of FSHR and AR which was associated with a concomitant decline in the expression of genes essential for germ cell division and differentiation, like KITLG, INHBB, CLDN11 and GJA1. CPF also induced a significant reduction in the activity of acetylcholinesterase in the testes and increased the total testicular antioxidant capacity. Our results suggested that CPF and its metabolite TCPy may induce reproductive toxicity by dysregulating the expression of Sc specific genes essential for spermatogenesis.

Chlorpyrifos-oxon induced neuronal cell death via endoplasmic reticulum stress-triggered apoptosis pathways.

Chlorpyrifos (CPF) is one of the organophosphorus pesticides widely used throughout the world. Epidemiological studies suggested a link between CPF exposure and neurologic disorders, while the molecular mechanisms remain inconclusive. In the present study, we investigated the impacts of chlorpyrifos-oxon (CPO), the major toxic CPF metabolite, on cell apoptosis, and explored possible mechanism associated with endoplasmic reticulum (ER) stress in SH-SY5Y cells. Results showed that CPO exposure induced dose-dependent apoptosis and expression of ER stress-related proteins in SH-SY5Y cells. Pretreatment with 4-PBA (an ER stress inhibitor) effectively inhibited the expression of GRP78, GRP94, p-IRE1α, and XBP1-s, and apoptotic events. Pretreatment with STF-083010 (an IRE1α inhibitor) partially attenuated CPO-induced apoptosis. In addition, CPO exposure significantly evoked the generation of reactive oxygen species (ROS) which could be eliminated by pretreatment of 4-PBA. Of note, buffering the ROS generation with antioxidant NAC had little impact on the expression of p-IRE1α, and only partially attenuated CPO-induced apoptosis. In contrast, co-pretreatment with NAC and STF-083010 effectively inhibited CPO-induced apoptotic events. Collectively, our results indicate that CPO exposure exerts neuronal cytotoxicity via ER stress downstream-regulated IRE1α/XBP1 signaling pathway and ROS generation-triggered apoptosis. These findings highlight the role of ER stress in CPF-induced neurotoxicity, and provide a promising target for the intervention of organophosphate-associated neurodegenerative diseases.

Adsorptive membrane separation for eco-friendly decontamination of chlorpyrifos via biochar-impregnated cellulose acetate mixed matrix membrane.

In this work, the phase inversion approach is used to synthesize a blended mixed matrix membrane from cellulose acetate polymer and sugarcane bagasse biochar. The experiments were carried out to estimate the extent of chlorpyrifos (CPS) pesticide removal. The results showed that the removal rate was more than 99% in making the filtered water suitable enough for domestic use. The physical and functional characteristics of the membranes, such as permeability, and contact angle were identified. The changes in the membrane characteristics were observed using scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction both before and after the experimental trials. Experiments were conducted to assess not only the rejection characteristics of CPS, as a function feed concentration, but also the effect co-ions on the rejection used to analyze the composition both before and after filtration. The effects of initial CPS concentration, biochar loading, and co-ions on the membrane were investigated. The membranes showed contact angles between 70° and 97° and a permeability between 0.25 × 1010 m Pa-1 s-1 and 0.31 × 1010 m Pa-1 s-1. The effective removal of CPS from the contaminated aqueous stream was attributed to a combination of adsorptive uptake and membrane-based separation. CPS was found to get adsorbed onto the membrane matrix through an intraparticle diffusion mechanism along with an irreversible monolayer adsorption. The membrane-solute adsorptive interaction was represented by Langmuir isotherm and intraparticle diffusion models with a maximum adsorption capacity of 192.3 mg g-1. The findings indicated the efficacy of biochar-cellulose acetate mixed matrix membrane for sustainable and eco-friendly treatment of chlorpyrifos contaminated water.

Maternal exposure to pesticides induces perturbations in the gut microbiota and blood-brain barrier of dams and the progeny, prevented by a prebiotic.

Exposure to pesticide residues during the first 1000 days of life can disrupt body homeostasis and contribute to chronic metabolic diseases. Perinatal chlorpyrifos (CPF) exposure alters gut microbiota (GM) balance, potentially affecting offspring's health. Given the GM influence on brain function, the primary aim is to determine if pesticide-induced dysbiosis (microbial imbalance) affects indirectly other organs, such as the blood-brain barrier (BBB). The secondary objective is to evaluate the prebiotics protective effects, particularly inulin in promoting microbial balance (symbiosis), in both mothers and offspring. A total of 15 or more female rats were divided in 4 groups: control, oral CPF-exposed (1 mg/kg/day), exposed to inulin (10 g/L), and co-exposed to CPF and inulin from pre-gestation until weaning of pups. Samples from intestines, spleen, liver, and brain microvessels underwent microbiological and biomolecular analyses. Bacterial culture assessed GM composition of living bacteria and their translocation to non-intestinal organs. RT qPCR and Western blotting detected gene expression and protein levels of tight junction markers in brain microvessels. CPF exposure caused gut dysbiosis in offspring, with decreased Lactobacillus and Bifidobacterium and increased Escherichia coli (p < 0.01) leading to bacterial translocation to the spleen and liver. CPF also decreased tight junction's gene expression levels (50 to 60% decrease of CLDN3, p < 0.05). In contrast, inulin partially mitigated these adverse effects and restored gene expression to control levels. Our findings demonstrate a causal link between GM alterations and BBB integrity disruptions. The protective effects of inulin suggest potential therapeutic strategies to counteract pesticide-induced dysbiosis.

Chlorpyrifos modulates the mouse gut microbiota and metabolic activity.

The organophosphate chlorpyrifos is a commonly used pesticide for fruits and vegetables despite its association with neurotoxicity in humans. While some studies suggest that organophosphates may impact the gut microbiota, no studies to date have investigated the direct effect of chlorpyrifos on the gut microbiota with doses that approximate environmentally relevant dietary concentrations (EPA chronic reference dose: 0.3 µg/kg/day in humans and EPA acute reference dose: 5 µg/kg/day in humans). Thus, we examined the influence of chlorpyrifos on the gut microbiota by assessment of bacterial physiology and metabolism using flow cytometry, 1H NMR-based metabolomics, and changes in the cecal microbiota community with 16S rRNA amplicon sequencing and analysis. Chlorpyrifos did not directly damage bacteria but rather perturbed bacterial metabolism. Chlorpyrifos exposure to bacteria increased the concentration of amino acids, carbohydrates, and nucleic acids. The relative abundances of Lactobacillus, Allobaculum, Roseburia, and Butyricicoccus increased after exposure to chlorpyrifos. Analyses of the 16S rRNA gene amplicon data predicted decreased amino acid biosynthesis and nucleic acid degradation and increased glycolysis which was supported by 1H NMR-based metabolomics. Collectively, these results demonstrate that environmentally relevant doses of chlorpyrifos can impact the metabolic activity of isolated gut microbes which may result in an imbalance in overall gut metabolic activity.

Fabrication and characterization of biodegradable hydrogel beads of guar gum for the removal of chlorpyrifos pesticide from water.

A new guar gum hydrogel beads were fabricated by dropping method from an aqueous solution of guar gum (GG) using ammonium persulphate and polyethylene glycol as initiator and crosslinker respectively, for the adsorption of chlorpyrifos (CP) from water. The semi-crystalline nature of the synthesized beads was confirmed by FESEM analysis. The TGA studies implied that the beads were thermally stable up to 600 °C. The maximum swelling ratio of 1400 gg-1 was attained at pH 9.2 and 80 min. The evidence of a strong absorption band was found in FTIR spectrum at 584 cm-1 due to -P=S of the adsorbed pesticide CP. The maximum adsorption of CP was found to be 220.97 mgg-1. The adsorption followed pseudo second-order kinetics and Langmuir adsorption isotherm with regression coefficients 0.9998 and 0.9938 which followed the chemisorption process. It is due to the hydrolysis of CP at pH 9.2 to yield 3,5,6-trichloropyridinol which in turn reacts with the carboxylic group present in GG giving -N-C=O linkage. A -ΔG indicates that the process is spontaneous and involves chemisorption which is thermodynamically and kinetically favorable and a -ΔH value (-10.37 kJ/mol) suggests that the adsorption is exothermic.

A comprehensive review on the treatment of pesticide-contaminated wastewater with special emphasis on organophosphate pesticides using constructed wetlands.

Pesticides pose a significant threat to aquatic ecosystems due to their persistent nature and adverse effects on biota. The increased detection of pesticides in various water bodies has prompted research into their toxicological impacts and potential remediation strategies. However, addressing this issue requires the establishment of robust regulatory frameworks to determine safe thresholds for pesticide concentrations in water and the development of effective treatment methods. This assessment underscores the complex ecological risks associated with organophosphate pesticides (OPPs) and emphasizes the urgent need for strategic management and regulatory measures. This study presents a detailed examination of the global prevalence of OPPs and their potential adverse effects on aquatic and human life. A comprehensive risk assessment identifies azinphos-methyl, chlorpyrifos, and profenfos as posing considerable ecological hazard to fathead minnow, daphnia magna, and T. pyriformis. Additionally, this review explores the potential efficacy of constructed wetlands (CWs) as a sustainable approach for mitigating wastewater contamination by diverse pesticide compounds. Furthermore, the review assess the effectiveness of CWs for treating wastewater contaminated with pesticides by critically analyzing the removal mechanism and key factors. The study suggests that the optimal pH range for CWs is 6-8, with higher temperatures promoting microbial breakdown and lower temperatures enhancing pollutant removal through adsorption and sedimentation. The importance of wetland vegetation in promoting sorption, absorption, and degradation processes is emphasized. The study emphasizes the importance of hydraulic retention time (HRT) in designing, operating, and maintaining CWs for pesticide-contaminated water treatment. The removal efficiency of CWs ranges from 38% to 100%, depending on factors like pesticide type, substrate materials, reactor setup, and operating conditions.

Neuroprotective effect of diosmin against chlorpyrifos-induced brain intoxication was mediated by regulating PPAR-γ and NF-κB/AP-1 signals.

Chlorpyrifos (CPF) is a widely used organophosphate (OP) pesticide. Unfortunately, pesticides are known to cause neuronal intoxication. Diosmin (DS) is an antioxidant, anti-inflammatory, and neuroprotective flavonoid with high efficacy and safety. We plan to investigate the efficacy of DS in treating CPF-induced neurotoxicity, as well as the mechanisms underlying the protective effects. In our study, rats were randomized into 5 groups: control, DS (50 mg/kg), CPF (10 mg/kg), CPF + DS (25 mg/kg), and CPF + DS (50 mg/kg). The results indicated that DS ameliorated neuronal intoxication induced by CPF, evidenced by decreasing Tau, p-Tau, and ß-amyloid. Histological examinations support these findings. DS significantly ameliorated CPF-induced neuronal oxidative injury by decreasing MDA content and elevating GSH, GST, and SOD levels mediated by PPAR-γ upregulation. DS suppressed CPF-induced brain inflammation by decreasing MPO enzymatic activity and TNF-α, IL-1ß, and IL-6 levels mediated by downregulation of NF-κB/AP-1(c-FOS and c-JUN) signal. Of note, DS protective effects were dose dependent. In conclusion, our data suggested that DS was a promising therapeutic strategy for attenuating CPF-induced neuronal intoxication by restoring oxidant-antioxidant balance and inhibiting inflammatory response in brain tissues.

Chlorpyrifos induces cytotoxicity via oxidative stress and mitochondrial dysfunction in HepG2 cells.

Chlorpyrifos (CPF), a widely used broad-spectrum organophosphate pesticide, has been associated with various adverse health effects in animals and humans. While its primary mechanism of action involves the irreversible inhibition of acetylcholinesterase, secondary mechanisms have also been suggested. The aim of the present study was to explore the secondary mechanisms of action involved in CPF-induced acute cytotoxicity using human hepatocarcinoma HepG2 cells. In particular, we investigated oxidative stress and mitochondrial function by assessing reactive oxygen species (ROS) generation, lipid peroxidation (LPO) and mitochondrial membrane potential (ΔΨm) alteration. Results showed that 24-h exposure to CPF (78.125-2500 µM) decreased cell viability in a concentration-dependent manner (IC50 = 280.87 ± 26.63 µM). Sub-toxic CPF concentrations (17.5, 35 and 70 µM) induced increases in ROS generation (by 83%), mitochondrial superoxide (by 7.1%), LPO (by 11%), and decreased ΔΨm (by 20%). CPF also upregulated Nrf2 protein expression, indicating the role of the latter in modulating the cellular response to oxidative insults. Overall, our findings suggest that CPF caused hepatotoxicity through oxidative stress and mitochondrial dysfunction. Given the re-emerging use of CPF, this study emphasizes the need for comprehensive analysis to elucidate its toxicity on non-target organs and associated mechanisms.

Effect of an organophosphate insecticide on the behaviour and physiology of the spider Misumenops maculissparsus (Araneae: Thomisidae).

Pests in agriculture cause significant economic damage by reducing production and product quality. While pesticides can be an alternative for pest control, their use has a significant impact on both the environment and human health. Chlorpyrifos, a widely used pesticide, affects both target and non-target organisms, including spiders. In this study, we investigated whether Misumenops maculissparsus spiders at three developmental stages (J0, J2, and adults) recognize the presence of the insecticide and how it affects their enzymatic activity. The results indicated that only J0 was able to recognize the insecticide and avoided surfaces treated with it. On the other hand, J0 and adults exhibited reduced acetylcholinesterase (AChE) activity and the activity of antioxidant enzymes was affected by the treatment. Superoxide dismutase (SOD) increased significantly in J0, catalase (CAT) in all stages, glutathione S-transferase (GST) in J2, and glutathione peroxidase (GPx) in J2 and adults. Chlorpyrifos exposure did not increase reactive oxygen species or alter cellular populations in any model.

A Sensitive SERS Sensor Combined with Intelligent Variable Selection Models for Detecting Chlorpyrifos Residue in Tea.

Chlorpyrifos is one of the most widely used broad-spectrum insecticides in agriculture. Given its potential toxicity and residue in food (e.g., tea), establishing a rapid and reliable method for the determination of chlorpyrifos residue is crucial. In this study, a strategy combining surface-enhanced Raman spectroscopy (SERS) and intelligent variable selection models for detecting chlorpyrifos residue in tea was established. First, gold nanostars were fabricated as a SERS sensor for measuring the SERS spectra. Second, the raw SERS spectra were preprocessed to facilitate the quantitative analysis. Third, a partial least squares model and four outstanding intelligent variable selection models, Monte Carlo-based uninformative variable elimination, competitive adaptive reweighted sampling, iteratively retaining informative variables, and variable iterative space shrinkage approach, were developed for detecting chlorpyrifos residue in a comparative study. The repeatability and reproducibility tests demonstrated the excellent stability of the proposed strategy. Furthermore, the sensitivity of the proposed strategy was assessed by estimating limit of detection values of the various models. Finally, two-tailed paired t-tests confirmed that the accuracy of the proposed strategy was equivalent to that of gas chromatography-mass spectrometry. Hence, the proposed method provides a promising strategy for detecting chlorpyrifos residue in tea.

Increased Levels of Phosphorylated-P38α Induce WNT/ß-Catenin and NGF/P75NTR/TrkA Pathways Disruption and SN56 Cell Death following Single and Repeated Chlorpyrifos Treatment.

Chlorpyrifos (CPF) biocide, exposure to which is mainly produced in the human population through diet, induces several neurotoxic effects. CPF single and repeated exposure induces memory and learning disorders, although the mechanisms that produce these outcomes are complex and not well understood. CPF treatment (single and repeated) of cholinergic septal SN56 cells induced an increase in phosphorylated-P38α levels that led to WNT/ß-Catenin and NGF/P75NTR/TrkA pathways disruption and cell death. These results provide new knowledge on the mechanisms that mediate CPF basal forebrain cholinergic neuronal loss induced by CPF single and repeated exposure and can help unravel the way through which this compound produces cognitive decline and develop efficient treatments against these effects.

Temporal distribution and ecological risk assessment for pesticides in water from the north-central coastal zone of Sinaloa, Mexico.

Water contamination with pesticides is one of the major pollution problems in northwestern Mexico, and this is due to the extensive use of pesticides in agriculture. In this research, water samples of ten sampling sites (fishing grounds, beaches, and both) were analyzed in the search for 28 pesticides (organochlorines, organophosphates, pyrethroids, carbamates, among other chemical classes), supplemented with a calculation of the resulting potential environmental risk. Pesticides were separated from the matrix by liquid-liquid extraction and quantified by gas chromatography coupled to electron micro-capture (organohalogenated) and pulsed flame photometric detectors (organophosphates). In addition, the ecotoxicological risk of pesticides in algae, invertebrates, and fish was assessed, based on seawater pesticide concentrations using the Risk Quotient (RQ) and Toxic Units (TU) approach. The results showed 18 pesticides identified in the analyzed samples, where cypermethrin and chlorpyrifos were identified with the maximum concentrations of 1.223 and 0.994 µg L-1, respectively. In addition, these two pesticides have been associated with acute toxic effects on algae, invertebrates, and fish. It is important to pay particular attention to the search for long-term alternatives to the use of chlorpyrifos and cypermethrin due to their high detection rates and the risks associated with their toxic properties. However, the adoption of alternative measures to synthetic pesticide control should be a priority, moving towards sustainable practices such as the use of biopesticides, crop rotation and polycultures.