Concentrations Of Chlorpyrifos Research Articles

Assessment of the Potential Phytotoxicity of Chlorpyrifos in the Wetland Macrophyte Bidens laevis (L.).

Chlorpyrifos (CPF) has been used worldwide, but its possible negative effects on macrophytes have been scarcely studied. The main goal of the present work was to assess the potential phytotoxic effects of CPF on different stages (seed and seedling) of the wetland macrophyte Bidens laevis. During the germination of seeds, stimulation of radicle growth at low concentrations of CPF (10µg/L) and inhibition of its elongation at 80µg/L CPF were observed. In seedlings, concentrations ≤ 160µg/L CPF did not exhibit adverse effects on growth after 7 days of exposure, despite the decrease of photosynthetic pigments and carotenoids observed at 40µg/L CPF compared to the control. Environmentally relevant concentrations of CPF altered neither oxidative stress biomarkers nor pigment contents in seedlings exposed for 48h, suggesting CPF would be non-toxic to B. laevis in natural scenarios.

Electrochemiluminescence sensor for organophosphorus pesticides based on the regulation of resonance energy transfer between negative charged gold nanorods and Ru(bpy)32+

Combined the electrostatic interaction of the negatively charged gold nanorods (AuNRs) (as acceptor) and Ru(bpy)32+ (as donor), an electrochemiluminescence resonance energy transfer (ECL-RET) sensor was constructed and applied for the detection of organophosphorus pesticides (OPs). Negatively charged AuNRs were synthesized by modifying AuNRs with polystyrene sulfonate (PSS) firstly, which can bind to Ru(bpy)32+ through electrostatic interaction so that the luminophore was absorbed by the acceptor, the resonance energy transfer occurred and only low ECL signal had been detected. Thiocholine can be produced by the hydrolysis process of acetylthiocholine (ATCh) with the help of acetylcholinesterase (AChE), which can bond with PSS-modified AuNRs (PSS-AuNRs) through gold-sulfur interaction, this caused the releasing of the adsorbed Ru(bpy)32+ into the solution and resulting in the restoration of the ECL intensity. However, the activity of AChE was inhibited by OPs, and the recovery process of the ECL signal was thus suppressed as well. In this study, chlorpyrifos was chosen as model target, the results indicated that the correlation between the ECL intensity and the logarithm of chlorpyrifos concentration showed remarkable linearity across 1 ng/mL to 1 mg/mL, achieving a detection limit of 0.51 ng/mL. The proposed system has been utilized for detecting OPs in real samples with satisfied results.

Acute toxicity of chlorpyrifos to some non-target freshwater organisms: which one is more toxic-technical grade or commercial formulation?

Chlorpyrifos is among the most widely sold organophosphates in the agriculture sector worldwide. Static bioassays were performed in the laboratory to compare the acute toxicity between the technical grade (94% a.i.) and commercial formulation (20% EC) of chlorpyrifos to four freshwater organisms: the crustacean zooplankton Cyclops viridis, the oligochaete worm Branchiura sowerbyi, the gastropod Pila globosa, and tadpole larvae of Duttaphrynus melanostictus. The recovery of actual chlorpyrifos concentrations in water after 2 h of exposure to the nominal concentrations ranged from 82.98% to 88.56%. The commercial formulation (F) of chlorpyrifos was found to be 1.94 to 2.76 times more toxic than the technical grade (T). Based on 96 h LC50 values of T and F chlorpyrifos, C. viridis was found to be most sensitive (0.56 and 0.25 μg/L) and P. globosa as most tolerant (1482 and 536 μg/L) to chlorpyrifos. Changes in LC50 values of both T and F chlorpyrifos were noted in respect of exposure hours for the three aquatic invertebrates and the tadpole larvae of the toad. In conclusion, the acute toxicity of chlorpyrifos to some non-target freshwater organisms differs between technical grade and commercial formulations.

Pesticides trapping performance of vegetative filter strips in black soil region, Northeast China: controlled experiments and VFSMOD-W modeling

The Northeast black soil region in China is an important grain-producing area where various pesticides are extensively used to increase grain yields. However, this practice poses serious risks to the ecological health of soil and water systems, necessitating effective measures. Vegetative filter strips (VFS) are commonly used to mitigate agricultural diffuse pollutants, but their efficiency varies across different regions, requiring assessment. This study employed flume experiments, the VFSMOD-W model, and redundancy analysis (RDA) to evaluate the efficacy of VFS in runoff, sediment, and pesticide removal, as well as influencing factors. The results showed that VFS reduced outflow rate of runoff by 8 %–64 % and sediment by approximately 90 %, achieving load removal rates of 61 % and 95 % respectively. Pesticide load removal efficiency ranged from 37 % to 94 %, with higher efficiency for adsorbed pesticides like chlorpyrifos compared to water-soluble ones like atrazine. Interflow and vertical seepage were significant pathways for pesticide transport in VFS, with chlorpyrifos concentrations at 4 %–26 % and atrazine at 20 %–37 % of inflow concentrations. The VFSMOD-W model accurately predicted VFS efficiency (NSE > 0.90), and RDA results indicated that environmental factors could explain 86.7 % of the variation in VFS performance, with soil vertical saturated hydraulic conductivity (VKS) being the most influential factor, followed by rainfall intensity (T), saturated soil water content (OS), initial soil water content (OI), and filter slope for each segment (SOA). Optimizing soil moisture characteristic factors and increasing infiltration are crucial for VFS performance. Applying VFSMOD-W for precise VFS design can help reduce construction costs. In the future, long-term field monitoring and evaluation of VFS efficiency after implementation should be conducted in the black soil region of Northeast China to provide data supporting the improvement of VFSMOD-W simulation accuracy. This will also offer recommendations for the government in formulating VFS configuration schemes.

The role of efflux transporters in cytotoxicity and intracellular concentration of chlorpyrifos and chlorpyrifos oxon in human cell lines

In this study, we investigated the role of two efflux transporters, p-glycoprotein (P-gp) and breast cancer resistance protein (BCRP), in the cytotoxicity and intracellular accumulation of the organophosphate pesticide chlorpyrifos (CPF) and its active metabolite, CPF-oxon (CPFO), in a human-derived liver cell line (HepG2) and kidney epithelial cell line (HK−2). The cytotoxicity to CPF and CPFO differed between cell lines where HK-2 had lower IC50 values which could be attributed to lower basal expression and inducibility of metabolizing enzymes, transporters, and nuclear receptors in HK-2 cells. In HepG2 cells, co-exposure of CPF with a specific inhibitor of either P-gp or BCRP enhanced the cytotoxicity of CPF while co-exposure of CPFO with VRP enhanced the cytotoxicity of CPFO, suggesting the role of these transporters in the elimination CPF and CPFO. Inhibition of efflux transporters did not affect the cytotoxicity of CPF and CPFO in HK-2 cells. Co-incubation of CPF with P-gp and BCRP inhibitors increased the intracellular concentration of CPF in HepG2 cells suggesting that both transporters play a role in limiting the cellular accumulation of CPF in HepG2 cells. Our results provide evidence that inhibition of efflux transporters can enhance CPF-induced toxicity through enhanced cellular accumulation and raises additional questions regarding how pesticide-transporter interactions may influence toxicity of mixtures containing pesticides and other environmental chemicals.

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 chlorpyrifoscontaminated water.

Evaluating the Potential of Bacillus Isolates for Chlorpyrifos Degradation and Their Role in Tea Growth Promotion and Suppression of Pathogens.

Pesticides employed for controlling domestic and agricultural pests are among the most dangerous environmental contaminants. Nevertheless, negligent usage and a lack of technical expertise have led to the contamination and pollution of various ecological niches. The extensive utilization of the organophosphate chlorpyrifos (CPs) for insect infestation control, coupled with its detrimental effects and persistence in the ecosystem, has led to calls for its removal from contaminated sites. The study is mainly focused on degradation of CPs; using viz. Bacillus wiedmannii A3 and Bacillus cereus P14 isolated from tea rhizosphere soil having pesticide contamination in Sonitpur district, Assam, India. These two bacterial strains were able to degrade CPs in vitro within 3days. Reverse-phase HPLC analysis suggested about 96% reduction of CPs concentration upon bacterial treatment. Again, in case of A3, GC-MS analysis revealed that CPs was modified to 2-hydroxy-3,5,6-trichloropyridine and chlorpyrifos-oxon, thus finally metabolized into non-toxic products. While analyzing P14, silane, dimethyl (2,2,2-trichloroethoxy) propoxy, and 3-aminobenzoic acid, N-trimethylsilyl-, trimethylsilyl ester were identified. These compounds were subsequently transformed into non-toxic products. In addition to this, they demonstrated a significant boost of plant growth-promoting traits in both absence and presence of CPs; also showed growth development in nursery scale condition. Moreover, they functioned as biocontrol agents against Phellinus lamaensis and Colletotrichum gloeosporioides, responsible for brown root rot and anthracnose in North East India tea plantations, respectively. Thus, the pesticide-tolerant Bacilli strains A3 and P14 could be used as bioremediation of contaminated sites and also as biostimulants, and biocontrols in tea crop production.

EFFECTS OF PESTICIDES RECIDUES ON TILAPIA ZILLII, SEDIMENT AND SURFACE WATER OF ERINLE DAM AND RIVER OSUN IN OSUN STATE

This study investigates the effects of selected pesticides on the health of aquatic ecosystems and humans in Erinle Dam and River Osun, Osun State, Nigeria. Focusing on Tilapia zillii, a commonly consumed fish in the region, the research assesses the potential health risks posed by pesticides found in the water, sediments, and fish tissues. Samples were collected following APHA guidelines and tested for pesticides like DDT, Heptachlor, Dieldrin, Aldrin, and Chlorpyrifos. The findings revealed high levels of DDT and Chlorpyrifos in both the water and fish, with Erinle Dam showing higher concentrations than River Osun. Specifically, DDT levels in River Osun's water averaged 199.08mg/kg, while Erinle Dam had 271.58mg/kg. Dieldrin and Chlorpyrifos also showed high concentrations, with Heptachlor and Aldrin absent in the water samples from both sites. Fish tissue analysis indicated higher pesticide levels in specimens from Erinle Dam compared to River Osun. DDT and Chlorpyrifos concentrations were notably high, while Dieldrin, Aldrin, and Heptachlor were present in lower amounts. Similarly, sediment analysis showed Erinle Dam with higher pesticide concentrations, particularly for DDT, Dieldrin, and Chlorpyrifos, while Heptachlor and Aldrin were absent.Overall, the study highlights significant pesticide contamination in Erinle Dam and River Osun, posing health risks to local fish consumers and indicating a need for stringent pesticide regulation and monitoring in the region.

Design of silver nanoparticle-embedded nano zirconium-based metal-organic frameworks for highly sensitive detection of chlorpyrifos in real samples.

Chlorpyrifos (CPS) is widely found in food and water sources due to agricultural use, posing health and environmental risks. Therefore, this work introduces a fluorescent sensor design of silver nanoparticle-embedded nano zirconium-based metal-organic frameworks (UiO-66-NH2@AgNPs) for accurate examination of CPS. Briefly, UiO-66-NH2 was synthesized hydrothermally, exhibiting weak luminescence owed to ligand-to-metal charge transfer (LMCT). Here, it limits its direct utility in fluorescence-based detection. To address this limitation, silver nanoparticles (AgNPs) were introduced into UiO-66-NH2, enhancing fluorescence via the metal-enhanced fluorescence (MEF) effect. Briefly, a comprehensive spectral analysis such as XPS, SEM, TEM, PXRD, etc., was performed to validate the synthesis of UiO-66-NH2@AgNPs. Subsequent evaluation revealed that CPS effectively quenched the luminescence intensity of UiO-66-NH2@AgNPs through a static quenching mechanism. The fluorescence intensity exhibited good linearity with CPS concentration in the span of 10 to 1,000 ng/mL, with a recognition limit of 191.5ng/mL(S/N = 3). The interaction involved Ag-S bond formation and electrostatic interactions, reducing fluorescence intensity. The method was confirmed through successful CPS detection in fruit samples. The UiO-66-NH2@AgNPs nanoprobe offers a simple, sensitive, and accurate platform for CPS sensing, with potential for future use in detecting CPS in fruits and vegetables.

Comparative Acute Toxicity Studies of Chlorpyrifos Technical Grade with its Emulsifiable Concentrate (20% EC) on Labeo rohita, a Freshwater Major Carp, and Mystus vittatus, a Freshwater Catfish.

Chlorpyrifos is widely used across the world as an organophosphate insecticide and frequently contaminates freshwater bodies through runoff from agricultural fields. In the laboratory, static bioassays were undertaken to examine differences in acute toxicity caused by exposure to the technical grade (94% a.i.) and an emulsifiable concentrate (20% EC) of chlorpyrifos to two species of freshwater fish, Labeo rohita and Mystus vittatus. The recovery of actual chlorpyrifos concentrations varied from 83% (technical grade, T) to 89% (emulsifiable concentrate, F) after two hours in water. The susceptibilities of the two fish species to the two types of chlorpyrifos varied. The 96-h LC50 values for T and F chlorpyrifos in L. rohita were 68 and 36µg/L, respectively, and 120 and 62µg/L in M. vittatus, respectively. As the exposure period was extended, the LC50 values gradually decreased. LC50 values between the technical grade and formulation were compared following the criteria of Mayer et al. (1986), Schmuck et al. (1994), APHA (1995), and Demetrio et al. (2014). It was concluded from the study that the emulsifiable concentrate (20% EC) of chlorpyrifos was more toxic than technical-grade chlorpyrifos.

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.

Biochar & fly ash amendments lower mortality and increase antioxidant activity in chlorpyrifos-exposed earthworms

The investigation presented a novel finding regarding mitigating stress induced by chlorpyrifos in Eisenia fetida by incorporating biochar derived from rice straw and fly ash as soil amendments. It was observed that phenolic compounds exhibit solubility in methanol, and the methanolic fraction exhibited notable inhibitory effects on lipid peroxidation and displayed antioxidant properties. The defence mechanism of E. fetida, comprising catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX), and various other enzymes, remained effective in neutralizing stressors without disruption when the earthworm was subjected to diverse chemical agents or stressful conditions. These enzymes served as indicative markers of toxicity induced by pesticide exposure, even at sublethal concentrations. The scavenging of free radicals by these enzymes ultimately safeguarded the organism. Fly ash and biochar emerged as two organic alternatives capable of alleviating stress by providing a protective mechanism. In this context, the study examined the impact of biochar and fly ash amendments on earthworm biomarkers. The mortality rate at the median lethal concentration of chlorpyrifos was reduced to less than 50% through 3% and 5% modifications. In contrast to the non-amendment group exposed to sublethal doses, the amendment group exhibited higher levels of oxidative stress and lower protein content. This observation indicated the presence of stress induced by the accumulation of free radicals, which increased in number with higher doses of chlorpyrifos. Moreover, the study highlighted the interconnected nature of total antioxidant capacity and total phenolic capacity values, with a decrease in these parameters signifying a shift in earthworm biomarkers.Graphical abstract

Isolation, Identification and Characterization of Bacteria Capable of Degrading Chlorpyrifos from Agricultural Soil at Amansea, Anambra State Nigeria.

Chlorpyrifos (O, O-diethyl O-(3,5,6-trichloro-2-pyridyl phosphorothioate) a broad spectrum moderately toxic organophosphorous insecticide is commonly used as pest control on grain, cotton, fruits, and vegetable crops against pest. Although it is important, its use has become one of the major causes of soil and water pollution. The present technique for removing chloryrifos insecticide from the environment which is biodegradation has shown to be more effective than any other physical or chemical methods like chemical hydrolysis. Therefore the aim of this research was to evaluate the biodegradation of chlorpyrifos insecticide by bacteria isolated from agricultural soil in Amansea, Anambra State, Nigeria. In the present study, two bacteria capable of degrading chlorpyrifos were isolated from Agricultural soil using mineral salts medium and characterized based on their physiological, biochemical, morphological and 16S rRNA sequencing as strains of Bacillus cereus ST06 and Chryseobacterium sp. 6024. Their growth response in mineral salts medium supplemented with 20mg/l concentration of chlorpyrifos was determined by monitoring the optical density at 600nm and at optimium condition of pH 6.5 and 300C for 28 days. The residual chlorpyrifos concentration after 28 days was also determined using Gas Chromatography- Electron Cathode Detector (GC-ECD). The result from one way ANOVA indicated that there were significant differences (P < 0.05) in the Growth responses to the insecticides by the test organisms. The result showed that Bacillus cereus ST06 and Chryseobacterium sp. 6024 reached maximum growth on 20mg/l chlorpyrifos with an arithmetic mean difference of 0.23±0.20 and 0.42±0.02 respectively on day 16 .There were also significant (<0.05) difference in concentration of residual chlorpyrifos degraded by the isolates obtained from the GC-ECD curves. Bacillus cereus ST06 and Chryseobacterium sp. 6024 degraded 63% and 57% of 20mg/l chlorpyrifos respectively. Bacillus cereus ST06 showed better results and possess potential to be used in biodegradation of 20mg/l Chlorpyrifos than Chryseobacterium sp. 6024. It is therefore recommended that further studies on the effect of varying Chlorpyrifos concentration on the bacteria singly and as a consortium be studied to better understand their potential for degrading chlorpyrifos efficiently.Keywords: Isolation, Identification, Characterization, Bacteria, Biodegradation, Chlorpyrifos and Insecticides

Persistent organic pollutants and chlorpyrifos in tissues of a histotrophic viviparous species, the Southern Eagle Ray Myliobatis goodei

Elasmobranchs are good indicators of marine pollution as they accumulate pollutants from water and food, and occupy different trophic levels. Concentrations of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and chlorpyrifos were quantified in muscle, liver, gonads, gills, and brain in both sexes and maturity stages of the Southern Eagle Ray, Myliobatis goodei, captured in Argentine coastal waters. Moreover, possible histological alterations in the liver and gonads were analyzed. Pollutant concentrations were pervasive across all tissues, with PCBs > OCPs > chlorpyrifos. Elevated pollutant levels were notably found in the liver and gills. We identified thirty-six PCB congeners in tissues, with low-chlorine congeners prevailing. Among OCPs, ∑DDT and ∑endosulfan were predominant. Females exhibited higher pollutant levels in most tissues compared to males, except in the gonads, and adults generally displayed elevated pollutant levels. Histological analysis revealed the presence of atretic follicles and melanomacrophages (MM). Continuous monitoring of pollutant levels, alongside their effects on physiological and ecological traits, is imperative for effective management and conservation efforts.

Multifunctional Metal-Organic Frameworks Driven Three-Dimensional Folded Paper-Based Microfluidic Analysis Device for Chlorpyrifos Detection.

Chlorpyrifos (CPF) residues in food pose a serious threat to ecosystems and human health. Herein, we propose a three-dimensional folded paper-based microfluidic analysis device (3D-μPAD) based on multifunctional metal-organic frameworks, which can achieve rapid quantitative detection of CPF by fluorescence-colorimetric dual-mode readout. Upconversion nanomaterials were first coupled with a bimetal organic framework possessing peroxidase activity to create a fluorescence-quenched nanoprobe. After that, the 3D-μPAD was finished by loading the nanoprobe onto the paper-based detection zone and spraying it with a color-developing solution. With CPF present, the fluorescence intensity of the detection zone gradually recovers, the color changes from colorless to blue. This showed a good linear relationship with the concentration of CPF, and the limits of detection were 0.028 (fluorescence) and 0.043 (colorimetric) ng/mL, respectively. Moreover, the 3D-μPAD was well applied in detecting real samples with no significant difference compared with the high-performance liquid chromatography method. We believe it has huge potential for application in the on-site detection of food hazardous substance residues.

Non-linear responses via agglomeration and aggregation of gold nanoparticles for surface-enhanced Raman spectroscopy (SERS) coupled with chemometric analysis for chlorpyrifos detection

This study investigates the behaviour of gold nanoparticles (AuNPs) when exposed to chlorpyrifos, an agricultural pesticide, and its application in detecting the pesticide via surface-enhanced Raman spectroscopy (SERS). Under synergistic addition of NaCl, AuNPs undergo agglomeration at lower chlorpyrifos concentrations but aggregation at higher concentrations, resulting in a distinctive nonlinear SERS response. A linear relationship is obtained between 0.001 and 1 ppm with detection limit (LOD) of 0.009 ppm, while an inverse response is observed at higher concentrations (1–1000 ppm) with a LOD of 1 ppm. Combining the colorimetric response of AuNP solutions, their absorbance spectra, and principal component analysis can improve detection reliability. The assay, coupled with a simple recovery method using acetonitrile swabbing, achieves high reproducibility in detecting chlorpyrifos in cucumber, even at concentrations as low as 0.11 ppm. This approach can be tailored for various chlorpyrifos concentrations not only in cucumbers but also in different food matrices.

Time-series variation in the locomotor behavior and vocal traits of Japanese medaka (Oryzias latipes) acutely exposed to organophosphorus pesticide chlorpyrifos

Organophosphorus pesticides (OPs), such as chlorpyrifos (CPF), are the most commonly used pesticides worldwide. Considering that OPs will eventually enter aquatic ecosystems due to runoff from agricultural lands, accidental leakage, and other unforeseen emergencies, monitoring water pollution of those substances is crucial for environmental protection and public health. In this study, Japanese medaka (Oryzias latipes) were exposed to CPF (0.03, 0.06, and 0.12 mg/L) for 6 h, and the time-series variations in their locomotor behavior and vocal traits were investigated. Compared with that measured before exposure, significantly changed locomotor behavior and vocal traits in Japanese medaka exposed to CPF could be observed at 4 h after exposure and thereafter, and the pattern of behavioral changes depends on the CPF concentrations. Exposure to CPF also changed the frequency-sound pressure level curve of Japanese medaka at 6 h after exposure, especially at 0.12 mg/L. Moreover, CPF exposure could significantly inhibit the acetylcholinesterase (AChE) activity in the brains and eyes of medaka, which exhibited significant correlations with the variation of locomotor behavioral and vocal traits. Considering that inhibiting the AChE activity is the primary mechanism underlying the neurobehavioral toxicity of all OPs, our finding suggested that simultaneously monitoring changes in the locomotor behavioral and vocal traits has a high potential to reflect the pollution of organophosphorus substances.

Effects of chlorpyriphos on haematological parameters in freshwater fish Anabas testudineus

Haematological measures are frequently employed as stress indicators in fish and to evaluate their overall health. This study evaluated the sublethal effects of the organophosphate insecticide chlorpyriphos on a number of haematological parameters in freshwater fish, specifically Anabas testudineus. Based on comparisons between control and experimental groups exposed to sublethal amounts of chlorpyrifos (0.125 and 0.250) at 7, 14, and 21 days, the effect was evaluated. Red blood cell counts, haemoglobin levels, WBC, and thrombocyte counts were found to decline as chlorpyrifos concentrations and days increased. White blood cell counts rose on the seventh day of exposure but fell on the fourteenth and twenty-first days when chlorpyrifos concentrations rose. According to the study, chlorpyrifos had a major negative effect on the fish's health, and haematological measures might be used as a diagnostic tool to determine whether A. testudineus has been exposed to chlorpyrifos.. KEYWORDS :A. testudineus, Chlorpyrifos, haemoglobin, Rbc, Wbc, haematological.

A highly sensitive electrochemical sensor based on surface molecularly imprinted polymers and graphene carbon nanotubes for highly selective detection of chlorpyrifos

AbstractPesticide residues represent a serious challenge for environmental protection, food safety, and public health. Addressing this challenge, this study strategically developed an electrochemical sensor with molecularly imprinted polymers (MIPs) as the recognition element to accurately detect chlorpyrifos in environmental samples. In this study, we used vinyl‐modified SiO2 as the matrix, methacrylic acid as the functional monomer, ethylene glycol dimethacrylate as the cross‐linker, and azobisisobutyronitrile as the initiator to synthesize the surface‐imprinted polymers. The development of the electrochemical sensor involved a detailed modification of the electrode, first by integrating carboxylated multi‐walled carbon nanotubes and graphene oxide to improve its properties, and then by applying a suspension of MIPs to the glassy carbon electrode. This process resulted in a sensor capable of detecting chlorpyrifos in environmental samples with high sensitivity. The electrochemical sensor, designed for chlorpyrifos detection, exhibited a robust linear response in peak current to varying concentrations of chlorpyrifos, ranging from 1 × 10−11 to 1 × 10−5 mol L−1. It achieved a detection limit as low as 1.85 × 10−11 mol L−1 (S/N = 3). Testing confirmed the sensor's exceptional repeatability, stability, and high selectivity towards chlorpyrifos, underscoring its efficacy. The demonstrated capabilities of this sensor suggest its substantial potential for widespread use in pesticide regulation and environmental conservation efforts.

Vitamin E alleviates chlorpyrifos induced glutathione depletion, lipid peroxidation and iron accumulation to inhibit ferroptosis in hepatocytes and mitigate toxicity in zebrafish

Organophosphates, a widely used group of pesticides, can cause severe toxicity in human beings and other non-target organisms. Liver, being the primary site for xenobiotic metabolism, is extremely vulnerable to xenobiotic-induced toxicity. Considering the numerous vital functions performed by the liver, including xenobiotic detoxification, protecting this organ from the ubiquitous pesticides in our food and environment is essential for maintaining homeostasis.In this study, we have investigated the impact of the organophosphate pesticide, Chlorpyrifos (CPF), on zebrafish liver at a concentration (300 μg/L) which is environmentally realistic. We have also demonstrated the role of dietary supplementation of α-tocopherol or Vitamin E (Vit E) (500 mg/kg feed) in mitigating pesticide-induced liver toxicity. Mechanistically, we showed that Vit E resulted in significant elevation of the Nrf2 and its downstream antioxidant enzyme activities and gene expressions, especially that of GST and GPx, resulting in reduction of CPF-induced intracellular lipid ROS and hepatic LPO. Further interrogation, such as analysis of GSH: GSSG ratio, intracellular iron concentration, iron metabolizing genes, mitochondrial dysfunction etc. revealed that CPF induces ferroptosis which can be reversed by Vit E supplementation. Ultimately, reduced concentration of CPF in zebrafish serum and flesh highlighted the role of Vit E in ameliorating CPF toxicity.