Cypermethrin Research Articles

Lifelong exposure to pyrethroid insecticide cypermethrin at environmentally relevant doses causes primary ovarian insufficiency in female mice

Pyrethroids are a class of widely used insecticides. Our recent epidemiological study of Chinese women reported that pyrethroid exposure was positively associated with the risk of primary ovarian insufficiency (POI). In this study, we utilized cypermethrin (CP), the most frequently detected pyrethroid in the environment, to recognize how lifelong and low-dose exposure to pyrethroids affects ovarian functions and the underlying mechanism(s). Female mice were exposed to CP at doses of human dietary intake of 6.7 μg/kg/day, an acceptable daily intake (ADI) of 20 μg/kg/day, or the chronic reference dose (RfD) of 60 μg/kg/day, starting from gestational day 0.5 until 44-week-old. We assessed effects on fertility, serum hormone levels, ovarian follicular development and ovarian transcriptomic profiles. Chronic exposure to CP at doses of ADI and RfD caused a significant reduction in the size of the primordial follicle pool on postnatal day (PND) 5 and the number of all types of follicles in 44-week-old mice, lower estrogen and higher gonadotropin levels, as well as decreased fertility. Significant increase in apoptosis and decrease in cell proliferation were observed in CP-exposed ovarian follicles from PND 5 and 44-week-old mice. Ovarian transcriptomic data showed that the pro-apoptotic protein BMF and the cell cycle inhibitor p27 were significantly up-regulated in CP-exposed ovaries. Cyp17a1, Cyp19a1 and Hsd17b1 genes involved in the key steps of steroidogenesis were down-regulated in the ovaries of female mice exposed to CP. This study first reported that lifelong exposure to CP at doses of ADI or RfD caused an ovarian phenotype similar to human POI in female mice and provided a mechanistic explanation. Our findings suggest that lifelong exposure to pyrethroids of low doses, which are recommended as ‘safe’ dosages, may have a significant impact on the ovarian health of female mammals and humans.

A comprehensive approach using multiple biomarkers to detect damage induced by pesticides in broad-snouted caiman (Caiman latirostris) under ex-situ conditions

Caiman latirostris is one of the two species of the order Crocodylia that inhabit Argentina and is considered a species of vital ecological and economic importance in the north-east of Argentina. In this region, pesticides are the most common contaminants in natural environments and wild caiman populations are subject to this contamination constantly. The aim of this study was to evaluate the effects the main pesticides used in the region: glyphosate (GLY), cypermethrin (CYP) and chlorpyrifos (CPF) -based formulations, as well as the mixture of them, on C. latirostris juveniles under semi-controlled condition of exposure (ex-situ) during 75 days. One hundred yearling caimans (10-month-old) were equally distributed into five experimental groups (20 animals per group): a negative control (NC -tap water), GLY 2% (Roundup® Full II formulation -RU), CYP 0.12% (Atanor® formulation), CPF 0.8% (Lorsban® formulation), and a mixture of the three pesticides (Mx3: GLY 2% + CYP 0.12% + CPF 0.8%). We applied early warning biomarkers to detect damage induced by these chemicals in peripheral blood: activity of the antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD), analysis of lipid peroxidation (LPO) by the thiobarbituric acid reactive substances (TBARS), DNA damage and specific base oxidation through the standard and modified comet assay (CA), chromosome damage by micronucleus (MN) test and other nuclear abnormalities (NAs), hematological and growth parameters. Results showed a statistically significant increase in MN and NAs frequency, DNA damage, with an important contribution of base oxidation for all exposed groups compared to the NC. Total white blood cells count (TWBCC), and growth parameters showed effects mainly at the Mx3. The principal component analysis (PCA) demonstrated more sensitivity for biomarkers associated to genetic damage, including base oxidation to DNA than LPO, antioxidant enzyme modulation, immunotoxicity or growth parameters, to detect pesticides effects, applied under conditions similar to that found in natural environments.

Biochar enhanced the performance of microalgae/bacteria consortium for insecticides removal from synthetic wastewater

The presence of pesticides in aquatic environments has threatened marine food resources, aquaculture, fisheries and human health; therefore, two most used insecticides were removed during this study. Two photobioreactors, including biochar and Chlorella vulgaris/activated sludge (reactor 1), and Chlorella vulgaris/activated sludge (reactor 2) were run to remove chlorpyrifos (CPF) and cypermethrin (CYP). Proteobacteria, Bacteroidetes and Chloroflexi were the dominant phyla of activated sludge. The optimization performance of both reactors was conducted by response surface methods. The performance of first photobioreactor was better than that in the second reactor, achieving abatement of 88.80% CPF and 93.12% CYP, at 69.7 h contact time and 0.32 mg/L initial concentration. The toxicity of CPF and CYP to Chlorella vulgaris was monitored under 0–4 mg/L of insecticide concentrations and 0–72 h contact time. The minimum chlorophyll content (2 mg/L) and protein (16.7%), and maximum growth inhibition (89.7%) were recorded at 4 mg/L insecticides concentration and 72 h contact time. Moreover, molecular docking simulation for catalytic enzyme degradation of Proteobacteria, Bacteroidetes and microalgae was carried out using individual hydrolase enzymes: carboxypeptidase in microalgae, isochorismatase hydrolase in Proteobacteria and alpha-L-arabinofuranosidase in Bacteroidetes. Ligand-binding energy, affinity and dimensions of ligands-binding sites in the enzyme cavity were calculated in each case. Hydrolase is an enzyme group that offers a promising practical application for the degradation of CYP and CPF due to its cavity features. This analysis demonstrated the mode of interaction of ligands with hydrolase enzymes in different species.

The effect and mechanism of cypermethrin-induced hippocampal neurotoxicity as determined by network pharmacology analysis and experimental validation

ABSTRACT Cypermethrin (CMN) is a widely used artificial synthetic pesticide that causes neurotoxicity in the hippocampus. However, the underlying toxicological targets and mechanisms remain unclear. In this study, network pharmacology analysis and in vitro models were integrated to investigate the effect and mechanism of CMN-induced hippocampal neurotoxicity. A total of 88 targets of CMN-induced hippocampal neurotoxicity were predicted. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes enrichment (KEGG) analyses suggested that these targets were related to multiple GO terms and signaling pathways. To further investigate underlying mechanism, the top 10 hub targets (Akt1, Tnf, Ptgs2, Casp3, Igf1, Sirt1, Jun, Cat, Il10, and Bcl2l1) were screened. Furthermore, cell viability and lactate dehydrogenase (LDH) assays demonstrated that CMN was toxic to HT22 cells in a time- and dose-dependent manner. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining revealed that treatment with CMN increased the proportion of apoptotic cells. In addition, the real-time quantitative polymerase chain reaction (RT-qPCR) results indicated that CMN altered the mRNA expression levels of most of the hub targets, with the exceptions of Igf1 and Jun. The results demonstrated that multiple targets and signaling pathways were involved in CMN-induced hippocampal neurotoxicity. These findings provided reference values for subsequent studies of the toxicological mechanism of CMN.

Oxidative stress is involved in the activation of NF-κB signal pathway and immune inflammatory response in grass carp gill induced by cypermethrin and/or sulfamethoxazole.

At present, the concentration of environmental pollutants, such as pesticides and antibiotics exposed in environment, especially in aquatic environment is increasing. Research on environmental pollutants has exploded in the last few years. However, studies on the combined effects of pesticides and antibiotics on fish are rare, especially the toxic damage to gill tissue is vague. In this paper, cypermethrin (CMN) and sulfamethoxazole (SMZ) were analyzed and found that there was a strong correlation between the pathways affected by the first 30 genes regulated by CMN and SMZ, respectively. Therefore, the toxic effects of CMN (0.651μgL-1) and/or SMZ (0.3μgL-1) on grass carp gill were studied in this paper. Histopathology, quantitative real-time PCR, and other methods were used to detect the tissue morphology, oxidative stress level, inflammation, and apoptosis-related indicators of the fish gills after exposure of 42days. It was found that compared with the single exposure (CMN/SMZ) group, the combined exposure (MIX) group had a more pronounced oxidative stress index imbalance. At the same time, nuclear factor-κB (NF-κB) signal pathway was activated and immuno-inflammatory reaction appeared in MIX group. The expression of tumor necrosis factor (TNF-α) in the rising range is 2.94 times that of the C group, while the expression of interleukin 8 (IL-8) is as high as 32.67 times. This study reveals the harm of CMN and SMZ to fish, and provides a reference and basis for the rational use of pesticides and antibiotics.

Surveillance of Culex mosquitoes in Jiangsu Province from 2018 to 2019

To investigate the distribution and density of Culex mosquito populations and the resistance of Culex pipiens pallens to insecticides in Jiangsu Province in 2018 and 2019. During the period from June to October in 2018 and 2019, six counties (districts, cities) were sampled in southern, northern and central Jiangsu Province as surveillance sites. The density of Culex mosquitoes was measured overnight using the light trapping technique. In addition, Culex pipiens pallens mosquitoes were collected from Hai'an of Nantong City and Yandu District of Yancheng City, central Jiangsu Province, and the sensitivity of female first filial generations to dichlorodiphenyltrichloroethane (DDT), malation, proposur, beta cypermethrin and deltamethrin was tested using the standard WHO insecticide susceptibility test assay. A total of 104 423 Culex mosquitoes were captured in six surveillance sites of Jiangsu Province in 2018 and 2019, and Culex quinquefasciatus (49.11%), Culex pipiens pallens (28.38%), and Culex tritaeniorhynchus (21.04%) were predominant species. The density of Culex mosquitoes started to increase since early June, peaked in July and tended to be low in late October. Culex pipiens pallens mosquitoes captured from Hai'an was susceptible to malation, while those from Yandu District were moderately resistant to malation. Culex pipiens pallens mosquitoes from both Yandu and Hai'an were moderately resistant to proposur, and were resistant to DDT, beta cypermethrin and deltamethrin. Culex quinquefasciatus, Culex pipiens pallens and Culex tritaeniorhynchus are predominant Culex species in Jiangsu Province. Culex pipiens pallens is resistant to DT, beta cypermethrin and deltamethrin in central Jiangsu Province.

Cypermethrin triggers YY1-mediated testosterone biosynthesis suppression

Cypermethrin (CYP), an extensively-used broad-spectrum pyrethroid pesticide, is regarded as a potential environmental endocrine disruptor with the anti-androgenic characteristic. To explore underlying roles of non-coding RNAs and the Jak/Stat pathway in CYP-mediated testosterone biosynthesis suppression, SD rats and Leydig cells were employed in this work. Results displayed that β-CYP decreased plasma testosterone levels and led to abnormal alterations of testicular histomorphology and ultrastructures. LncRNA XIST and miR-142–5p were co-localized in the cytoplasm of Leydig cells, but the expression of XIST was inhibited by β-CYP while that of miR-142–5p was induced. Then overexpressed miR-142–5p dampened the Jak1/Stat1 pathway by directly targeting Jak1. Transcription factors NFκB and YY1 impeded by β-CYP were positively regulated by the Jak1/Stat1 pathway. Bidirectional Co-IP and ChIP assays demonstrated that NFκB interacted with and modulated YY1 by directly binding to the promoter region of YY1. ChIP, qPCR, and YY1 knockdown/overexpression assays indicated that YY1 acted as a transcriptional activator to directly modulate steroidogenic StAR and 3β-HSD in Leydig cells. Taken together, miR-142–5p sponged by lncRNA XIST directly targets the Jak1/Stat1 pathway, which regulates steroidogenic StAR and 3β-HSD via NFκB and YY1, and ultimately dampens testosterone production in Leydig cells.

The Effect of Different Repeated Doses of Cypermethrin on the Behavioral and Histological Alterations in the Brain of Rabbits (Oryctolagus cuniculi)

Among pesticides, insecticides are being used to control external parasitic infestations in animals and crops and combat vermin in and around houses. Insecticides are associated with harmful effects on body organs, including brain damage. To explore the toxic effects of pyrethroid insecticides on the brain, this study was conducted to explore the neural-toxicological effects of cypermethrin (CY) in apparently healthy adults and weight-matched male rabbits (n=40). Different doses (0, 50, 100, and 150mg.kg-1 body weight) of CY mixed in mustard oil were injected intraperitoneally at weekly intervals for 71 days in rabbits assigned into four equal groups: W, X, Y, and Z. The rabbits under experiment were monitored daily for various clinical signs of toxicity and fodder intake, whereas the body weight was noted weekly. Two rabbits from each group were euthanized fortnightly, and the brain from each animal was collected for morphological and histological examination. The CY-treated rabbits showed various clinical signs, decreased body weight gain, and reduced relative brain weight. Microscopically, the CY-treated rabbits showed Purkinje neurons of the cerebellum and pyramidal neurons of the cerebral cortex at different stages of development. Therefore, CY could lead to brain and behavior alterations in rabbits and increase the risk of diseases.

Biomarkers of genotoxicity, immunotoxicity and oxidative stress on Caiman latirostris (Broad-snouted caiman) hatchlings exposed to pesticide formulations and mixtures widely used in agriculture

Pesticide formulations are currently considered as one of the main factors responsible for environmental contamination worldwide. Consequently, several wild species can be affected by the over use of pesticides related to agriculture activity. The aim of this study was to evaluate genotoxicity, immunotoxicity and oxidative stress on Caiman latirostris hatchlings exposed in vivo to sub-lethal concentrations of three insecticide formulations: Endosulfan (END)-, Cypermethrin (CYP)-, and Chlorpyrifos (CPF)- based formulations, two Glyphosate (GLY)- based herbicide formulations and two different ternary complex mixtures of them.C. latirostris hatchlings, 20 days old were exposed in plastics containers with pesticide solutions (by voluntary immersion) during two months, with a progressive decrease in pesticide concentrations through time, in order to simulate their degradation in water under natural conditions.After exposure, blood samples were taken to all animals for the analysis of genotoxicity (Comet assay, Micronucleus and other nuclear abnormalities) immunotoxicity (Total and differential white blood cell counts) and oxidative stress (Lipoperoxidation and the antioxidant enzymes Catalase and Superoxide dismutase).Results indicated that the five formulations tested, as well as the complex mixtures of them, induced genotoxicity, alteration in white blood cell counts and oxidative stress at environmentally relevant concentrations. Mixtures showed different interactions depending of the biomarker analyzed.This study constitutes an integral evaluation of the effect of five pesticide formulations and two possible complex ternary mixtures widely used in soybean crops in Argentina, on different endpoints on a native reptile species, C. latirostris.

Insecticide resistance status of important malaria vectors in a tribal district of Rajasthan

Investigations have been carried-out in a malaria prone district of Rajasthan to determine insecticide resistance status of important malaria vector species viz. Anopheles culicifacies, An. annularis and An. stephensi, against insecticides being used under National Malaria Control Programme in two Block Public Health Centres of Banswara district of Rajasthan. An. culicifaies, except one canal irrigated village, where it was found susceptible to DDT, was found either resistant or intermediate resistant. Against Malathion An. culicifacies was found susceptible in one rain-fed irrigation village, whereas in all other villages, it was found either resistant or intermediate resistant. Against synthetic pyrethroids An. culicifacies was found susceptible to both Alpha Cypermethrin and Cyfluthrin, except one rain-fed irrigation village, where against Cyfluthrin, the species exhibited intermediate resistance. This is a first report of synthetic pyrethroid resistance from Rajasthan. An. annularis, was found resistant to DDT in both canal irrigated and rain-fed irrigation villages, however, against Malathion it exhibited resistance in canal irrigated village and intermediate resistance in rain-fed irrigation village, however, against Alpha Cypermethrin and Cyfluthrin the species was found totally susceptible in both the areas. An, stephensi was tested only against Alpha Cypermethrin in a canal irrigated village and found totally susceptible. In the study area An. culicifacies have exhibited triple resistance, showing resistance to DDT, Malathion and intermediate resistance to cyfluthrin, however, An. annularis exhibited double resistance to DDT and Malathion.

Structure and Property of Pesticide Intercalation into Laponite Assisted by Silane Coupling Agent

AbstractThe APTES‐LAP was first prepared by silane coupling agent of 3‐aminopropyltriethoxysilane (APTES) intercalation into laponite (LAP). The effect of m(APTES)/m(LAP) mass ratio and reaction time on the structure of APTES‐LAP were investigated. The results showed that the interlayer distance of APTES‐LAP was about 1.75∼1.89 nm as the mass ratio of m(APTES)/m(LAP) was between 0.5 and 2.0, reaction time was 24 h. Then, pesticides of beta‐cypermethrin (BCT) and imidacloprid (IMP) were separately introduced into APTES‐LAP to prepare BCT/APTES‐LAP and IMP/APTES‐LAP composites. Their structures and thermal stabilities were characterized by powder X‐ray diffraction (XRD), fourier transform infrared spectroscopy (FT‐IR), thermogravimetry/differen‐tial thermal analysis (TGA/DTA), hydrogen magnetic resonance (1H NMR) and scanning electron microscopy (SEM) techniques. Compared with APTES‐LAP, the first diffraction peaks of BCT/APTES‐LAP and IMP/APTES‐LAP moved forward, and interlayer distance increased to about 2.2 nm. The existence of APTES and pesticide were further confirmed in the gallery. Furthermore, the release behaviors of pesticide from BCT/APTES‐LAP and IMP/APTES‐LAP in pH 5.0 and 6.8 buffer solutions were investigated and discussed. The pseudo‐second‐order and the parabolic diffusion models were used to fit the release data. This work was helpful to develop the application of composites in pesticide controlled release formulation.

Procyanidin B2 protects neurons from cypermethrin-induced oxidative stress through the P13K/Akt/Nrf2 signaling pathway

To explore whether procyanidin B2 (PCB2) regulates the P13K/Akt/Nrf2 signaling pathway to protect neurons from oxidative stress induced by cypermethrin (CYP). Primary cultures of cerebral cortex neurons from C57BL/6 mice were randomly divided into 5 groups: normal control group (cultured in serum-free neurobasal-B27 medium), PCB2 treatment group(treated with 5 μg/mL PCB2 for 24 h), CYP exposure group(treated with 50 μmol/L CYP for 24 h), PCB2 pretreatment group(pretreated with 5 μg/mL PCB2 for 30 min followed by exposure to 50 μmol/L CYP for 24 h), and LY294002 treatment group (pretreated with 20 μmol/L LY294002 for 30 min before treatment with PCB2 for 30 min and then CYP for 24 h).CCK-8 assay was used to analyze the neuronal viability after the treatments.Reactive oxygen species (ROS) production in the cells was detected using the fluorescent probe DCFH-DA and flow cytometry.The changes in nuclear morphology and mitochondrial membrane potential of the cells were examined with Hoechst 33342 and JC-1 staining, respectively.Western blotting was performed to detect the protein expressions of Nrf2, HO-1, p-Akt and Akt in the cells. In CYP exposure group, the cells showed significantly decreased viability and mitochondrial membrane potential with obvious apoptotic morphological changes and abnormal ROS production.By comparison, the cells in PCB2 preconditioning group showed improved cell survival rate, reduced abnormalities in nuclear morphology, increased mitochondrial membrane potential, and lowered intracellular ROS production.CYP exposure caused Nrf2 nuclear translocation and up-regulated Nrf2, HO-1, p-Akt protein expressions in the cells, which were inhibited by PCB2 pretreatment.Inhibition of the P13K/Akt signaling pathway obviously neutralized the protective effect of PCB2 against CYP-induced neuronal injury. PCB2 regulates the Nrf2/ARE signaling pathway by activating the P13K/Akt signaling pathway to protect mouse cerebral cortical neurons against oxidative injury induced by cypermethrin.

Deleterious effects of two pesticide formulations with different toxicological mechanisms in the hepatopancreas of a freshwater prawn

The aim of this study was to evaluate the acute effects of the pyrethroid cypermethrin (CYP) and the last generation pesticide spirotetramat (STM) on the prawn Macrobrachium borellii. Initially, the 96-h LC50 was determined in adult prawns. Then, prawns were exposed to sublethal concentrations of pesticides (5% and 20% of the 96-h LC50 values) for four days and hepatopancreas were dissected for biomarkers analyses. Total protein and uric acid content, glutathione S-transferase (GST) activity, levels of lipid peroxidation (LPO), and protein oxidation (PO) were evaluated. Additionally, the presence of histopathological changes, lipofuscins, and neutral lipids accumulation were analyzed. The 96-h LC50 values were 0.12 μg/L and 8.2 mg/L for CYP and STM, respectively. The total proteins and uric acid content were not significantly affected by the treatments (p > 0.05). STM significantly affected the GST activity only at the highest concentration (p < 0.001). However, LPO and OP levels were affected by the lowest concentrations of both pesticides (p < 0.003). CYP and STM caused dose-dependent histological damage as was indicated by the histopathological index. The accumulation of lipofuscins showed a dose-dependent response, while the neutral lipids were significantly accumulated in the prawns exposed to the lowest concentration of both pesticides (p < 0.001). The integrated biomarker index (IBRv2) results indicated that the histological parameters represented the most sensitive biomarkers in M. borellii exposed to CYP and STM. Besides, the pyrethroid showed the highest response at concentration ranges that could be present in its natural environments.

Testicular deficiency associated with exposure to cypermethrin, imidacloprid, and chlorpyrifos in adult rats

The testicular deficiency associated with exposure to three widely used insecticides in Egyptian agriculture was evaluated. Animals were orally treated with sub-lethal dose (1/50 of the oral LD50) of cypermethrin (CYP), imidacloprid (IMC), and chlorpyrifos (CPF) at 5, 9 and 1.9 mg/kg/day, respectively, five times a week for one month. The CYP, IMC, and CPF exposure resulted in a significant decline in animal body weight, sperm count, motility, normality, and viability with increased head and tail deformities. Significant reduction in serum testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), testis superoxide dismutase (SOD), and reduced glutathione (GSH) levels. In contrast, catalase (CAT), lipid peroxidation (LPO), and protein carbonyl content (PCC) levels were significantly stimulated. Jointly, obtained results were confirmed by microscopic examination of testis sections. The present data concluded that the CYP, IMC, and CPF have a public health impact and violently interferes with male rat reproductive system.

Investigating the degradation behavior of Cypermethrin (CYP) and Chlorpyrifos (CPP) in peach orchard soils using organic/inorganic amendments.

Reducing toxic effects of pesticide residues in agricultural soils through organic amendments is an eco-friendly technique. Cypermethrin (CYP) and Chlorpyrifos (CPP) are widely used pesticides in peach growing orchards in Swat valley of Pakistan. The aim of the current study was to investigate the degradation behavior of CYP and CPP in soil by the application of different combination of organic/inorganic amendments. A total of 36 soil samples were used in the current incubation study which was collected from 4 peach orchards in district Swat, Khyber Pakhtunkhwa (KPK), Pakistan. Different amendments including urea, farm yard manure (FYM) and saprofil were applied alone and in various combinations. The initial concentrations of CYP and CPP in the tested soil was range from 0.94 to 4.8 mg kg−1 and 0.024 to 4.12 to mg kg−1. Soil samples were taken at 5, 15, 30 and 45 days after exposure to different treatments. The extraction of pesticides from soils was done through quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction method. Soils amended with urea, FYM and saprofil individually and in combinations significantly reduced the concentrations of CYP and CPP. However, the concentration of CYP (24.6) and CPP (27.0) in soil showed higher reduction through the application of FYM. While the concentrations of CYP and CPP were declined with the 5, 15, 30 and 45 days intervals, however, reduction at day 30 and 45 was faster for CYP (16.7 to 8.46) than CPP (20.2 to 12.3). At day 5 and 15, the CYP (42.5 to 30.7) was slightly lower than CPP (42.9 to 32.7).The highest half-life value (t ½) of CYP was in control treatment (32 days) and the shortest was soil amended with FYM (18.6 days). While the longest half-life value (t ½) of CPP was maximum in control treatment (42 days) and the minimum was in FYM (22 days). Based on our findings, it was concluded that soil application of FYM is recommended for the degradation of CYP and CPP.

Which Is More Toxic? Evaluation of the Short-Term Toxic Effects of Chlorpyrifos and Cypermethrin on Selected Biomarkers in Common Carp (Cyprinus carpio, Linnaeus 1758).

The general aim of this study was to investigate the negative short-term effects of different concentrations of chlorpyrifos (CPF) and cypermethrin (CYP), based on the EU legislation (MAC-EQS) in common carp (Cyprinus carpio Linnaeus, 1758) under laboratory conditions and to compare their toxicity. The fish were exposed to the pesticides for 96 h and then different histological and biochemical biomarkers were investigated in the gills and liver, and bioaccumulation analyses were conducted. The chemical studies showed increased pesticide concentrations in the gills as the first site for pollutants compared to the liver at the 96th hour. In addition, the histological analyses showed severe alterations in the gills and liver after exposure to both tested pesticides. In the gills, we found mainly intense proliferative and, to a lesser extent, degenerative changes and alterations in the circulatory system, such as necrosis and vasodilation. In the liver, regressive and progressive lesions, as well as circulatory disturbances and inflammation, were observed. The regressive lesions showed a higher degree of expression compared to the other changes. Furthermore, we found altered enzymatic activities—catalase, glutathione reductase, and glutathione peroxidase—in the liver, compared to the control. Overall, both tested pesticides impacted the studied biomarkers in common carp, even at concentrations lower than those permitted by law. However, the results of the comparative analysis showed a relatively higher toxicity of CYP compared to CPF in the fish. Still, questions persist as to whether the observed changes are adaptive or entirely destructive. To avoid any danger or risk, these pesticides must be applied cautiously, especially near water bodies.

The Potential Protective Role of Hydroxytyrosol against Cypermethrin-induced Histological, Immunohistochemical and Biochemical Changes in Lung of Adult Male Albino Rats

Background: Cypermethrin (CYP) is a synthetic pyrethroid used as a pesticide. It induces toxicity of different organs. Hydroxytyrosol (HT) can protect against oxidant-induced toxicity and promote programmed apoptosis counteracting cellular infiltration.Aim: The present study aimed at examining the CYP-induced histological, immunohistochemical and biochemical changes in rat lungs and clarifying the protective role of HT. Materials and Methods: Forty adult male albino rats, their wights were (150–200 g), were used. The rats were equally distributed into four groups as follows; control group gavaged by oral route with corn oil (1 ml/kg/day), HT group gavaged by oral route with HT (50 mg/kg/day dissolved in I ml distilled water), CYP-treated group gavaged by oral route with CYP (20 mg/kg/day dissolved in I ml corn oil), and CYP+HT treated group treated orally with CYP and HT (as previous doses) for 14 days. All groups underwent histological lung examination, immunohistochemical, morphometric and biochemical analysis.Results: This study showed that CYP caused a significant rise in MDA with a significant decline of SOD, CAT, and GSH levels. Histological changes revealed extensive cellular infiltration, thickening alveolar septum, increased angiogenesis with areas of hemorrhage, extravasation of blood, and decreased areas of ventilation in lungs of rats treated with CYP. Moreover, ultrastructural observations confirmed previous results. A noticeable improvement of the affected lung tissues was observed with HT treatment in the form of regaining of normal epithelial bronchial lining, re-inflation of alveoli and nearly intact intima of the blood vessels as well as restoration of type II pneumocyte structure.Conclusion: HT was proved to ameliorate the CYP-induced histological, immunohistochemical and biochemical changes in rat lung, without abolishing it. This could be explained by HT's anti-inflammatory and antioxidant properties and scavenging abilities against active free radicals. These findings can be of value for future clinical applications.

Cypermethrin-Induced Lung Damage in Albino Rats: The Preventive Impact of Moringa oleifera

Cypermethrin (CYP) is a popular environmental toxicant because of its wide-ranging use as a broad-band insecticide. The purpose of this research was to explore the potential impact of Moringa oleifera leaves extract (MOLE) as a protective agent against cypermethrin-induced lung toxicity in male albino rats. Forty experimental animals were allocated into four groups. G1 served as the negative control, G2, G3 and G4 were orally treated with MOLE (250 mg/kg body weight), CYP (26.15mg/kg body weight) and CYP + MOLE, respectively. CYP oral administration for 28 days elevated the levels of oxidative stress biomarkers like Malondialdehyde, superoxide dismutase, catalase and glutathione S-transferase and caused a decline in the content of reduced glutathione in the lung tissue of the rats. Lung injury was verified by histopathological changes evidenced by interstitial pneumonia, marked perivasculitis, focal pulmonary hemorrhage, haemosidrosis and pulmonary edema in CYP-exposed rats. Co-administration of MOLE mitigated the induced oxidative stress and histopathological alterations. As a result, Moringa oleifera can prevent cypermethrin-induced lung toxicity due to its free radical scavenging and antioxidant properties.

Insecticides and Drought as a Fatal Combination for a Stream Macroinvertebrate Assemblage in a Catchment Area Exploited by Large-Scale Agriculture

This case study documents responses in a headwater macroinvertebrate assemblage to insecticide pollution and hydrological drought. In 2014, the Doubravka brook (Czech Republic) was damaged by a large overflow of a mixture of chlorpyrifos (CPS) and cypermethrin (CP). In 2016–2017, this brook was then affected by severe drought that sometimes led to an almost complete absence of surface water. We found significant relationships between the strength of both these disturbances and the deeper taxonomic levels of both the overall macroinvertebrate assemblage (classes) and the arthropod assemblage alone (orders and dipteran families), as well as the functional feeding groups (FFGs). The CPS-CP contamination was mostly negatively correlated to arthropod and non-arthropod taxa and was positively correlated only with FFG collector-gatherers; on the other hand, the drought was negatively correlated to Simuliidae, Ephemeroptera, Trichoptera, and the FFG of grazer-scrapers and passive filterers. Drought conditions correlated most positively with Isopoda, Ostracoda, Heteroptera, adult Coleoptera, and predator and active filterer FFGs. The chosen eco-indicators (SPEARpesticides, SPEARrefuge, BMWP, and EPT) used as support information reveal the poor ecological status of the whole assemblage, including the control site, the cause of which is most likely to be the exploitation of the adjacent catchment area by large-scale agriculture. This type of agricultural exploitation will undoubtedly affect macroinvertebrate assemblages as a result of agrochemical and soil inputs during run-off events and will also exacerbate the effect of droughts when precipitation levels drop.

Efficacy of contact insecticides for the control of the lesser mealworm, Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae)

The lesser mealworm, Alphitobius diaperinus is a common pest of poultry farming facilities, the presence of which harbors diseases and economic loss, but it also occurs in different types of storage and processing facilities, such as feed mills. In this study, we evaluated the efficacy of three contact insecticides, alpha cypermethrin, spinosad, and pirimiphos methyl, against adults and larvae of A. diaperinus in a series of two bioassays. In the first series of bioassays, mortality rates were determined after 1, 3, 7 and 14 days of exposure on concrete dishes treated with the above insecticides. The results show that all three insecticides were effective for the control of this species, since after 14 days of exposure mortality exceeded 90% for both adults and larvae. Spinosad had a definite advantage over the other two insecticides, providing complete (100%) insect mortality after 14 days of exposure. In the second series of bioassays, the presence of food was evaluated to determine the effects of immediate and delayed mortality. We found that the presence of food in the concrete dishes decreased the levels of delayed mortality of the exposed individuals. All three insecticides showed an increased level of delayed mortality, either with or without food, but mortality did not reach 100% for any of the combinations tested. These results present a valid series of data for creating a standardized means of control against this pest that has beset poultry facilities for years.