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Pyrethroid are the primary insecticides used for controlling of Bactricera dorsalis, a highly destructive and invasive fruit pest. Field populations have developed serious resistance, especially to ß-cypermethrin. While mutations in the voltage-gated sodium channel (Vgsc) are a common mechanism of pyrethroid resistance, variations in BdVgsc associated with ß-cypermethrin resistance remain unclear. Here, we reported the resistance levels of five field populations from China, with resistance ratio ranging from 1.54 to 21.34-fold. Cloning the full length of BdVgsc revealed no specific or known amino acid mutations between the most resistant population and the susceptible strain. However, three types of partial intron retention (IRE4-5, IRE19-f and IREL-24) were identified in BdVgsc transcripts, with these intron retentions containing stop codons. The expression of IRE4-5 transcripts and total BdVgsc showed different trends across developmental stages and tissues. Exposure to ß-cypermethrin led to increased expression of IRE4-5. Comparison of genomic and transcriptional sequences reveled that IRE4-5 transcripts had two types (IRE4-5.5 T and IRE4-5.6 T) caused by genomic variations. Both field and congenic strains indicated that homozygotes for IRE4-5.5 T had lower IRE4-5 transcript levels than homozygotes for IRE4-5.6 T. However, congenic and field strains exhibited inconsistent results about the association of expression levels of IRE4-5 transcripts with sensitivity to ß-cypermethrin. In summary, this study is the first to identify intron retention transcripts in the Vgsc gene from B. dorsalis and to examine their expression patterns across different developmental stages, tissues, and strains with varying sensitivities to ß-cypermethrin. The potential role of the intron retentions of BdVgsc in insecticide toxicity is also discussed.

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To compare the impact of two pesticide dose forms on Blattella germanica (B. germanica)resistance enzymes.The micro-drop technique was utilized on subcultured B. germanica, and the metabolic enzyme activity was assessed.Using spectrophotometry, the relative enzyme activities of B.germanica were determined.Profile analysis was used to compare the enzyme activities of beta-cypermethrin in both nanoemulsion and traditional emulsion forms.Findings: The suppression percentages of the acetylcholinesterase enzyme (AchE), GST, and P450-O demethylases across different pesticide formulations were analyzed using regression equations, yielding F = 31.18, P < 0.001; F = 9.18, P < 0.001; and F = 4.58, P < 0.02.Conclusion: The suppression of AchE, GST, and P450-O demethylase by beta-cypermethrin nanoemulsion was more significant compared to the beta-cypermethrin emulsifiable concentrate.The study concluded that beta-cypermethrin nanoemulsion had a significant impact on insect detoxifying enzymes compared to beta-cypermethrin emulsifiable concentrate due to their numerous advantages.

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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.

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This study aimed to investigate the protective effects of Allium jesdianum essential oil (AJEO) in decreasing cypermethrin toxicity for rainbow trout. First, the safety of the 0%, 0.5%, 1%, and 1.5% AJEO supplements was assayed after 60 days. Then, the protective effects of AJEO were studied on fish exposed to 12.5% 96h LC50 cypermethrin after 14 days. Results showed that 1 and 1.5% AJEO administration enhanced protease and lipase activities in the intestine and improved growth performance. Moreover, feeding fish with 1 and 1.5% AJEO increased catalase (CAT) and superoxide dismutase activities (SOD) and decreased malondialdehyde (MDA). Also, AJEO increased glutathione peroxidase (GPx) activity in serum. However, exposure to cypermethrin significantly decreased these enzyme activities and increased MDA. The oxidative biomarkers remained normal in fish fed with AJEO after exposure to cypermethrin. The administration of 1 and 1.5% AJEO significantly decreased cortisol and glucose levels, alkaline phosphatase (ALP), lactate dehydrogenase, aspartate aminotransferase and alanine aminotransferase activities. Although exposure to cypermethrin significantly increased these biochemical biomarkers, AJEO could adjust them. A significant effect of 1% AJEO on total protein and globulin was observed before and after exposure to cypermethrin. Exposure to cypermethrin decreased all immunological parameters in the serum and mucus. However, administration of 1% AJEO increased protease, lysozyme (LYS) activities, total immunoglobulin (Ig), complement C3 and C4, and nitroblue tetrazolium (NBT) in the serum and ALP, LYS, protease activities and Ig in mucus. In conclusion, results showed that AJEO could potentially decrease the toxicity effects of cypermethrin in fish.

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Heterothermic insectivorous bats are supposed to experience differential adverse effects of insecticidal pollutants depending on their seasonal and/or daily variation of metabolic and detoxification rates. Here, we investigated effects of imidacloprid, cypermethrin and fipronil on Nyctalus noctula bat-derived hepatocytes through cytotoxicity, cell inhibition and death at different concentrations (0.01, 0.1, 1, 10, 100, 1000 µg/ml), exposure times (10, 24, 48 hrs), incubation temperatures simulating hibernation (8 °C), daily torpor (20 °C), normothermy (37 °C) and active flight (40 °C), and cytochrome P450 addition. Toxic effects were significantly influenced by temperature (p < 0.05), with strong cytotoxicity after 10 hour exposure to fipronil or cypermethrin at 37 and 40 °C, cell replication inhibition (all insecticides at 8 °C) and cellular stimulation, with slight culture proliferation after 48 hours (all insecticides at 40 °C). Replacing protected chiropterans with cell cultures is a way to assess and extrapolate risks of insecticides for bats.

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Rhipicephalus microplus is among the most important ectoparasites for livestock. The use of synthetic acaricides has raised some concerns due to the selection of tick populations that are resistant to acaricides and environmental contamination. Therefore, plant extracts have been used as alternatives for the treatment of animals infested with ticks. In this study, R. microplus populations from seven different dairy farms were collected and assessed for their resistance to the acaricides cypermethrin or trichlorfon. Larvae of the most resistant population were used in assays to evaluate the acaricide effect of leaf extracts from plants of the Brazilian savanna. The most active extracts were also tested against fully engorged females. Among seven tick populations, five and three showed resistance level ≥ III for cypermethrin or trichlorfon, respectively. The most resistant tick population was evaluated in mortality assays with the plants Piptadenia viridiflora, Annona crassiflora, Caryocar brasiliense, Ximenia americana, and Schinopsis brasilienses. The ethanolic extracts of C. brasiliense, X. americana and S. brasilienses showed higher larvicidal effects in comparison to the other extracts and cypermethrin. The ethanolic extract of X. americana showed 60.79 % efficacy against fully engorged females of the acaricide resistant tick strain. The ethanolic extracts of C. brasiliense, X. americana, and S. brasilienses showed peaks in HPLC-DAD, indicating the presence of tannins and flavonoids. Three of the plants showed promising results and should be explored in further studies to develop novel tools to control R. microplus in cattle.

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Diptera and Lepidoptera species have the highest levels of insecticide resistance, and the mechanism of drug resistance has been studied in detoxification metabolism genes such as P450, GST, EST, and ABC. Since Bactrocera dorsalis are resistant to a variety of chemicals, the pattern and mechanism of resistance in Bactrocera dorsalis have been investigated from a variety of aspects such as detoxification metabolism genes, detoxification enzymes, intestinal symbiotic bacteria, and synergists in the world. In this study, 51 species and 149 detoxification metabolism genes were annotated in the Suppression Subtractive Hybridization (SSH) library, and 12 candidate genes related to beta-cypermethrin resistance were screened and quantitatively expressed in this library. Two genes were found to be upregulated in the egg stage, three genes in the larval stage, one gene in the pupal stage, and five genes in the adult stage, and four genes were found to be upregulated in the midgut and the malacca ducts in the midgut. The expression of cyp6g1, cyp6a22, GST-Epsilon9, and Trypsin-4 genes was upregulated in resistant strains, with the most obvious upregulation occurring in the midgut and the Malpighian tubules. These results provide new insights into the study of pesticide resistance in quarantine insects.

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The tobacco cutworm, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) is an economically important agricultural polyphagous pest worldwide. It has shown high resistance to several insecticides, including cypermethrin, a synthetic pyrethroid that is used in large-scale commercial agricultural applications. The present study investigated the development of selection-induced resistance to cypermethrin and associated fitness costs in S. litura. After continuous exposure to cypermethrin for consecutive fifteen generations, the cypermethrin-selected population (CYP-Sel) of S. litura developed a 21.2-fold resistance. The CYP-Sel strain had a relative fitness of 0.16 when treated with LC50, prolonged larval duration, and development time. Meanwhile, the strain also showed shorter adult duration, lower fecundity, and hatchability compared with the Unsel-Lab population. CYP-Sel population showed a significant disadvantage in intrinsic rate of natural increase (rm), net reproductive rate (Ro), and finite rate of increase (λ) when compared to the Unsel-Lab population. This knowledge could help to design resistance management strategies against this particular pest, along with potential management strategies to overcome the development of resistance.

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The extensive utilization of pesticides results in their frequent detection in aquatic environments, often as complex mixtures, posing risks to aquatic organisms. The hook snout carp (Opsariichthys bidens) serves as a valuable bioindicator for evaluating the impacts of environmental pollutants in aquatic ecosystems. However, few studies examined the toxic effects of pesticides on O.bidens, let alone the characterization of the combined effects resulting from their mixtures. This study aims to elucidate the toxic effects of beta-cypermethrin and pyraclostrobin on O.bidens, individually and in combination, focusing on biochemical, transcriptional, and molecular responses. By organizing and analyzing the toxicogenomic databases, both pesticides were identified as a contributor to processes such as apoptosis, oxidative stress, and inflammatory responses. The acute toxicity test revealed comparable acute toxicity of beta-cypermethrin and pyraclostrobin on O.bidens, with LC50 being 0.019 and 0.027 mg/L, respectively, whereas the LC50 decreased to 0.0057 and 0.0079 mg/L under the combined exposure, indicating potential synergistic effects. The activities of enzymes involved in oxidative stress and detoxification were significantly altered after exposure, with superoxide dismutase (SOD) and catalase (CAT) increasing, while malondialdehyde (MDA) levels decreased. The activity of CYP450s was significantly changed. Likewise, the expression levels of genes (mn-sod, p53, esr, il-8) associated with oxidative stress, apoptosis, endocrine and immune systems were significantly increased. Combined exposure to the pesticides significantly exacerbated the aforementioned biological processes in O.bidens. Furthermore, both pesticides can modify protein activity by binding to the surface of SOD molecules and altering protein conformation, contributing to the elevated enzyme activity. Through the investigation of the synergistic toxic effects of pesticides and molecular mechanisms in O.bidens, our findings highlight the importance of assessing the combined effects of pesticide mixtures in aquatic environments.

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The study aimed to investigate the combined effects of chlorpyrifos and cypermethrin combined on dopaminergic neurotoxicity, motor behaviours and level of selected inflammatory proteins in rats compared to either alone for delineating an interaction between these two pesticides. The rotarod and grip strength tests were employed to assess neurobehavioural changes. The striatal dopamine content and expression of tyrosine hydroxylase (TH), α-synuclein, cyclooxygenase-2 (COX-2), and tumour necrosis factor-α (TNF-α) proteins in the nigrostriatal tissue were measured. Chlorpyrifos impaired the neurobehavioural indexes, reduced the striatal dopamine level, augmented the level of α-synuclein, COX-2, and TNF-α and attenuated the expression of TH similar to but a little less than cypermethrin. Half the dose of both pesticides together produced additional neurotoxicity compared with the usual (highest employed) dose of either alone. The results showed that chlorpyrifos induced moderately less dopaminergic neurotoxicity than cypermethrin. In the combination, they produced a little higher toxicity than either pesticide alone.

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This study examined the pattern of resistance to widely applied synthetic pyrethroids, i.e., cypermethrin and deltamethrin, against larvae of Rhipicephalus microplus ticks sampled from Marathwada region in Maharashtra, India. The study also examined the role of α- and ß-esterases and glutathione-S-transferase (GST) in resistance development. All eight R. microplus isolates tested were resistant to deltamethrin (RL IV), having RR50 values from 6.88 to 131.26. LPT analysis exhibited the resistance level II deltamethrin resistance in Beed and Hingoli, III in Dharashiv, and IV in Sambhajinagar, Parbhani, Latur, Jalna, and Nanded isolates. The LIT analysis showed that Dharashiv field isolates had the lowest LC50 value of 229.09 ppm against cypermethrin, while Sambhajinagar field isolates had the highest at 489.78 ppm. The RR50 ranged from 1145.45 to 2448.9. Seven isolates were level I resistant to cypermethrin while the Jalna isolate was level II resistant. In larvae treated with deltamethrin and cypermethrin, the activity of α- and ß-esterase enzymes increased significantly compared to control groups. The enzyme ratios in treated larvae ranged from 0.7533 to 1.7023 for α-esterase and 0.7434 to 3.2054 for ß-esterase. The Hingoli isolate treated with cypermethrin exhibited the highest α-esterase activity (903.261), whereas Sambhajinagar isolate had the highest GST enzyme ratio (2.8224) after deltamethrin exposure. When exposed to cypermethrin, the Hingoli isolate showed the highest GST enzyme ratio, 2.0832. The present study provides the current resistance status in tick populations from Marathwada region indicating deltamethrin and cypermethrin to be ineffective for tick control. The results also suggest that SP compounds should be regulated in this region and alternative control strategies should be introduced.

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Natural enemies of arthropods contribute considerably to agriculture by suppressing pests, particularly when combined with chemical control. Studies show that insect recovery after insecticide application is rare. Here, we discovered the recovery of the predatory bug Arma chinensis from knockdown following the application of ß-cypermethrin but not five other insecticides. A. chinensis individuals were more tolerant to ß-cypermethrin than lepidopteran and coleopteran larvae, which did not recover from knockdown. We assessed A. chinensis recovery by monitoring their respiration and tracking locomotion through the entire process. We identified and verified the trans-regulation of detoxifying genes, including those encoding cytochrome P450s and α/ß-hydrolase, which confer recovery from ß-cypermethrin exposure in A. chinensis, by mitogen-activated protein kinase (MAPK) and cAMP response element binding protein (CREB). Furthermore, we discovered a novel mechanism, the neurotransmitter clearance, in vivo during the recovery process, by which the insect initiated the removal of excessive dopamine with a degrading enzyme ebony. Overall, these results provide mechanistic insights into the detoxification and neurotransmitter clearance that jointly drive insect recovery from insecticide exposure.

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In this study, the toxicity of the pesticide cypermethrin and the protective properties of royal jelly against this toxicity were investigated using Allium cepa L., a model organism. Toxicity was evaluated using 6 mg/L cypermethrin, while royal jelly (250 mg/L and 500 mg/L) was used in combination with cypermethrin to test the protective effect. To comprehend toxicity and protective impact, growth, genotoxicity, biochemical, comet assay and anatomical parameters were employed. Royal jelly had no harmful effects when applied alone. On the other hand, following exposure to cypermethrin, there was a reduction in weight increase, root elongation, rooting percentage, mitotic index (MI), and chlorophyll a and b. Cypermethrin elevated the frequencies of micronucleus (MN) and chromosomal aberrations (CAs), levels of proline and malondialdehyde (MDA), and the activity rates of the enzymes catalase (CAT) and superoxide dismutase (SOD). A spectral change in the DNA spectrum indicated that the interaction of cypermethrin with DNA was one of the reasons for its genotoxicity, and molecular docking investigations suggested that tubulins, histones, and topoisomerases might also interact with this pesticide. Cypermethrin also triggered some critical meristematic cell damage in the root tissue. At the same time, DNA tail results obtained from the comet assay revealed that cypermethrin caused DNA fragmentation. When royal jelly was applied together with cypermethrin, all negatively affected parameters due to the toxicity of cypermethrin were substantially restored. However, even at the maximum studied dose of 500 mg/L of royal jelly, this restoration did not reach the levels of the control group. Thus, the toxicity of cypermethrin and the protective function of royal jelly against this toxicity in A. cepa, the model organism studied, were determined by using many different approaches. Royal jelly is a reliable, well-known and easily accessible protective functional food candidate against the harmful effects of hazardous substances such as pesticides.

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The aims of this study were to evaluate the exposure to permethrin and cypermethrin of young children aged between 2 and 5 years in Nakhon Pathom and Sing Buri provinces, Thailand. A questionnaire that included general demographic information, household characteristics, insecticide usage and exposure-related behavior in children was used to interview parents or family caregivers. Permethrin and cypermethrin concentrations on floor surfaces and children's hands, as well as their urinary metabolites, were analyzed by gas chromatography coupled with mass spectrometry. The results showed that permethrin and cypermethrin were detected in 62% and 83% of the children's hand wipe samples, with geometric mean (GM) levels of 0.02 µg and 0.04 µg, respectively. Permethrin and cypermethrin were detected in 79% and 93% of floor surface wipe samples, with GM levels of 0.90 µg/m2, and 1.49 µg/m2, respectively. For children's urine, the GM concentrations of cis- and trans-DCCA, 3-PBA, and total pyrethroid metabolites were 0.84, 0.31 and 1.23 nmol/g creatinine, respectively. This study found that household insecticide product usage and having a tile floor were associated with increased permethrin concentrations on the children's hands and floor surfaces. However, cypermethrin concentrations on floor surfaces were significantly higher in families using aerosol insecticide sprays and insecticide products in the living room and bedroom. The predictors of the total pyrethroid, DCCA and 3-PBA metabolites are permethrin on children's hands or floor surfaces and cypermethrin on floor surfaces.

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G-protein coupled receptors (GPCRs) are the largest and most diverse transmembrane receptor family in the cell. They are involved in regulating a wide range of biological processes, including behavior, reproduction, and development. However, GPCRs have not yet been identified in Zeugodacus cucurbitae. The current study focuses on the GPCRs identification, classification, distribution, and their expression analysis under ß-cypermethrin stress to uncover novel targets for pest management and assist in the development of effective strategies for controlling the melon fly population. We identified 80 GPCRs genes including 50 GPCRs identified in family A, 17 GPCRs identified in family B, 8 identified in family C, and 5 identified in family F. Z. cucurbitae GPCRs showed significant differences in both the number of genes in families or subfamilies, as well as the sequencing of the genes. Interestingly, newly identified GPCRs genes are expressed differently at various developmental stages of Z. cucurbitae. Further, we evaluated these 80 GPCRs using Realtime quantitative PCR to confirm their expression between ß-cypermethrin-resistant (RS) strain and susceptible strain (SS) of Z. cucurbitae. We identified 50 GPCR genes were highly overexpressed in a RS. Among these genes, eight genes were strongly induced by the 30% lethal concentration (LC) while two genes were significantly increased by the 50% LC of ß-cypermethrin. This first genome-wide profiling and characterization of GPCRs could lay foundation for unraveling detoxification mechanism and target site modifications which may improve the insect resistance and could be effective insecticide targets for Z. cucurbitae management.

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Dermanyssus gallinae, a worldwide pest in birds, has developed varying degrees of resistance to insecticides. The ATP-binding cassette (ABC) transporters are essential for the removal of xenobiotics from arthropods. However, our knowledge about ABC transporter proteins in D. gallinae is limited. Forty ABC transporters were identified in the transcriptome and genome of D. gallinae. The resistant population displayed an augmented metabolic rate for beta-cypermethrin compared to the susceptible group, with a remarkable increase in the content of ABC transporters. Verapamil was found able to increase the toxicity of beta-cypermethrin in the resistant population. Results from qRT-PCR analysis showed that eleven ABC transcripts were more highly expressed in the resistant population than the susceptible group at all stages of development, and beta-cypermethrin was observed to be able to induce the expression of DgABCA5, DgABCB4, DgABCD3, DgABCE1 and DgABCG5 in D. gallinae. RNAi-mediated knockdown of the five genes was observed to increase the susceptibility of resistant mites to beta-cypermethrin. These results suggest that ABC transporters, DgABCA5, DgABCB4, DgABCD3, DgABCE1 and DgABCG5 genes, may be related to beta-cypermethrin resistance in D. gallinae. This research will serve as a foundation for further studies on mechanism of insecticide resistance, which could be beneficial for controlling D. gallinae.

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The present study was conducted to evaluate the effects of exposure to sublethal concentrations of cypermethrin on growth, phenotypic traits, and metabolic and antioxidant enzymes activities of monosex tilapia (Oreochromis niloticus). The median lethal concentration (LC50) of cypermethrin was initially ascertained to be 0.04 ppm after 12 h of exposure to three concentrations (0.04, 0.20, and 1.0 ppm) via the Probit analysis method. The sublethal exposures were obtained for 3 months at 0.0016, 0.008, and 0.04 ppm of cypermethrin. The growth performance, phenotypic traits, and enzymatic activity were analyzed. The research findings revealed a notable impact of cypermethrin on the growth performance of monosex tilapia, with a significant (p < 0.05) decrease in weight observed as the concentration increased. The experiment documented a significant change (p < 0.05) in the phenotypic traits of standard length, total length, tail length, trunk length, eye diameter, body area, and color patterns, but not dressing percentage. Furthermore, it was observed that the activities of amylase and protease in both the intestine and muscle decreased significantly (p < 0.05) with increasing concentrations of cypermethrin, except for amylase in the muscle, where no significant change was noted (p > 0.05). The results also demonstrated significant reductions (p < 0.05) in the activity of metabolic enzymes, specifically superoxide dismutase and catalase, following exposure to sublethal levels of cypermethrin. The study suggested that sublethal exposure of pyrethroid alters the growth, phenotypic traits, metabolic enzymes activities, and immunity of monosex tilapia.

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BACKGROUND: Due to the constant and improper use of chemicals, including pesticides, many substances, and their degradation products can accumulate in the soil and negatively affect its organisms. METHODS: In this study, morphological methods, Gram-staining, and Matrix-Assisted Laser Desorption/Ionzation Time of Flight Mass Spectrometry (MALDI-TOF MS) methods were used to isolate bacteria from agricultural soils, while genetic identification was conducted using 16S rRNA. The density of bacteria was determined using the spectrophotometric method, and the residual amount of cypermethrin was determined and analyzed using Gas chromatograohy-mass spectrometry (GC-MS) methods. RESULTS: Nine isolates were obtained from various agricultural soils. Isolate No. 3 showed the greatest effectiveness against cypermethrin and was selected for further research. Isolate No. 3 was identified as the Ochrobactrum intermedium strain PDB-3 and was registered in the National Center for Biotechnology Information (NCBI) database (GenBank: OL587509.1). Using this strain, the influence of various external factors on the degradation of cypermethrin was studied. This bacterium demonstrated 100% degradation of cypermethrin in 20 days under optimal conditions (temperature: 30 °C; optical density (OD) = 0.2; cypermethrin concentration: 80 ± 0.02 mg/kg). In addition, PDB-3 changed the original structure of cypermethrin into various intermediate metabolites, such as 2-hydroxy-3-phenoxy benzeneacetonitrile, 3-phenoxybenzaldehyde, 3-phenoxybenzaldehyde, methyl stearate, anethol, citral, and phenol. CONCLUSIONS: The results obtained using PDB-3 provide the basis for large-scale field trials on the bioremediation of cypermethrin-contaminated soils.

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Cypermethrin (CP) is a neurotoxic insecticide found accumulated in oysters, one of the most commonly consumed seafoods, posing potential health risks to the human body. We designed a gastrointestinal tracing method allowing for accurate quantification of the propulsion of chyme and further established the mouse in vivo digestion model to explore the behavior of CP in the digestion of raw, steamed, and roasted oysters. The results showed that bioaccumulation of CP in oysters may be accompanied by the biotransformation of CP. Thermal processing decreased both the CP content in oysters and its bioaccessibility. The small intestine is the main site for CP digestion and absorption. The cis-isomers of CP might finally accumulate in the body at a higher ratio and further become the predominant configuration for toxic effects. Taken together, the study contributes to the risk assessment of the dietary exposure of CP from aquatic products.

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This study evaluated pesticide exposure practices, and the potential health risks of drinking water and consuming fish from the cultivated wetlands of Ndop, Cameroon. Six hundred and twenty-six questionnaires were conveniently administered to farmers (≥ 26 years old) in a cross-sectional study to assess exposure practices and dietary risks. The Chi-square and Pearson correlation coefficients were used to establish relationships between variables. The PRIMET model was used to predict a worst-case dietary risk. The pesticide handling practices of 90% of farmers were inadequate. Chlorpyriphos, lambda-cyhalothrin, fipronil, and paraquat dichloride posed a possible dietary risk at recommended and applied doses, with chlorpyrifos having the highest exposure toxicity ratio (ETRdiet = 36.72). Paraquat dichloride, fipronil, and lambda-cyhalothrin posed a possible dietary risk at 26.3%, 58.3%, and 62.2% of their recommended concentrations, respectively. Remarkably, the dietary risk for cypermethrin was acceptable at 5.8 times its recommended dose (ETRdietR = 0.29). The significant positive correlation (p = 0.000) between PECfish and ETRdiet, suggests a possible health risk of consuming fish and drinking water harvested from the wetlands, thus the need for replacing pesticides posing possible risks at lower or recommended concentrations with less toxic alternatives and to train farmers on pesticide application practices.

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