Microtransplantation of rat brain neurolemma into the plasma membrane of Xenopus laevis oocytes is an ex vivo method used to study channels and receptors in their native state using standard electrophysiological appro...Microtransplantation of rat brain neurolemma into the plasma membrane of Xenopus laevis oocytes is an ex vivo method used to study channels and receptors in their native state using standard electrophysiological approaches.In this review,we show that oocytes injected with adult rat brain neurolemma elicited tetrodotoxin-sensitive inward ion currents upon membrane depolarization,which were increased in a concentration-dependent manner by treatment with the pyrethroid insecticides permethrin and deltamethrin.Under our initial protocols,oocyte health was reduced over time and neurolemma incorporation varied between batches of oocytes from different frogs,limiting the usefulness of the assay for regulatory issues.A collection of changes to the assay procedure,data acceptance criteria,and analysis method yield substantially improved precision and,hence,assay performance.These changes established this ex vivo approach as a toxicologically relevant assay to study the toxicodynamic action of pyrethroids on ion channels in their native state using neurolemma fragments prepared from juvenile and adult rat brains.展开更多
Of the tumors diagnosed in the female dogs have the highest mammary neoplasias incidence. These neoplasias can be influenced by environmental contaminants. Despite evidence of pyrethroid toxicity, carcinogenic potenti...Of the tumors diagnosed in the female dogs have the highest mammary neoplasias incidence. These neoplasias can be influenced by environmental contaminants. Despite evidence of pyrethroid toxicity, carcinogenic potential has not yet been sufficiently elucidated, there is a need to investigate their involvement in mammary tumor. In previous studies, pyrethroid residues were detected in female dogs with mammary neoplasia, however was not investigate the influence of this insecticide in the genesis and aggressiveness of mammary cancer. This study aimed to investigate possible relations between pyrethroid residues and aggressiveness of mammary carcinoma in female dogs. Fifty selected female dogs were divided into five groups of 10 animals each: the Control group, female dogs without mammary neoplasia;the groups Luminal A, Luminal B, HER-2 Superexpression and Basal were constituted by female dogs that presented inguinal mammary carcinoma classified immunohistochemically. The aggressiveness of carcinomas was evaluated by immunohistochemistry (HER-2, p63, estrogen receptor). Residual concentrations of the pyrethroids from the mammary gland and fat tissue adjacent to it were determined by HPLC. Data were analyzed by Chi-Square test. Of the all animals, six presented residues of pyrethroids in mammary samples and 10 presented it in fat tissue samples. There was no statistical evidence that pyrethroids are involved in mammary carcinoma aggressiveness in female dogs.展开更多
Diagnosis and biological behavior of breast cancer of female dog represent one of the biggest challenges facing the Veterinarian in recent years. Due to its exponential growth and the degree of aggressiveness, the exa...Diagnosis and biological behavior of breast cancer of female dog represent one of the biggest challenges facing the Veterinarian in recent years. Due to its exponential growth and the degree of aggressiveness, the exact cause of this tumor is probably multifactorial and it is believed that may suffer influence from environmental factors. Among the suspected environmental contaminants are the pyrethroids. Aiming to investigate the participation of pyrethroids in tumorigenesis in female dogs, a study was conducted using 50 female dogs, 22 were positive for simple breast carcinoma (Group I), 18 with a diagnosis of complex breast carcinoma (Group II) and 10 negative (Group III) for breast cancer. In order to detect DNA damage, the Comet assay was performed on mammary samples of these animals, which also had samples submitted to the technique of High Performance Liquid Chromatography (HPLC), which aimed to quantify the concentration of pyrethroids. The results of HPLC of each animal were compared with those obtained by the Comet assay analysis of variance and the means were compared by the test groups “Student T” at the significance level of p ￡ 0.05. Despite presenting correlation between the amount of DNA damage and tumor aggressiveness, no statistical differences were found in the DNA damage of different histologic types of breast carcinoma. As for pyrethroids, even these were detected in 22% of tumor tissues and peritumoral fat, there was no difference in DNA damage between cells exposed and not exposed to environmental contaminant.展开更多
Pyrethroid is widely used in developing countries and is a potential threat to human health.So putting forward an effective pyrethroid cleaning method is of vital importance.Clearance of fenpropathrin,cypermethrin and...Pyrethroid is widely used in developing countries and is a potential threat to human health.So putting forward an effective pyrethroid cleaning method is of vital importance.Clearance of fenpropathrin,cypermethrin and deltamethrin in cabbage by using ultrasonic treatment accompanied with different baking soda concentrations were investigated in this study.The results of response surface methodology showed that the maximum clearance rate was 70.61% for fenpropathrin under the optimal power,treated time,treated temperature and baking soda concentration,which were 260.02 W,10 min,20.15◦C and 0.014 g/mL,respectively.Similarly,the maximum removal efficiency was 73.72% for cypermethrin under 240 W,13.84 min,19.53℃ and 0.014 g/mL,and 92.15%for deltamethrin under 238.99 W,12.42 min,25℃ and 0.013 g/mL.The clearance rate of pyrethroid by this method was significant higher(P<0.05)than traditional cleaning methods(bathing and running water washing).The contents of the compositions such as vitamin C,total soluble sugar,protein and dietary fiber,texture and sensory evaluation of cabbage were not found obvious changes after the ultrasonic treatment combined with baking soda(P>0.05).Results showed that ultrasonic treatment combined with baking soda was an effective way to eliminate the fenpropathrin,cypermethrin and deltamethrin in cabbage without influencing cabbage quality.展开更多
[Objective] In order to provide a reference for safe and reasonable use of pyrethroids in cigarette production,the degradation behaviors of three kinds of pyrethroids in cigarette production environment were studied. ...[Objective] In order to provide a reference for safe and reasonable use of pyrethroids in cigarette production,the degradation behaviors of three kinds of pyrethroids in cigarette production environment were studied. [Method]Three kinds of pyrethroids( permethrin,cyfluthrin and cis-cypermethrin) were administrated to two media( cut tobacco and iron sheet surface) in cigarette production environment at MRLs concentration,and the first sampling was conducted at 24 d post administration. Afterwards,sampling was performed once every 7 d,with a total of six times. The degradation rates of insecticides in different media were calculated,and degradation models were established. [Result] The contents of three kinds of insecticides in two media gradually declined with the prolongation of time,and degradation rates presented the trend of fast-slow-fast; the degradation rates of permethrin,cyfluthrin and cis-cypermethrin in cut tobacco at 36 d post administration were 97. 14%,88. 89% and 95. 38%,respectively; the degradation rates on iron sheet surface were 29. 95%,48. 99% and 40. 24%,respectively.The half lives of three kinds of insecticides in cut tobacco were 1- 2 d,while those on iron sheet surface were 6- 10 d. [Conclusion]The contents of three kinds of insecticides in two media gradually declined with the prolongation of time,and their degradation regularity accorded with first order kinetic equation.展开更多
Synthetic pyrethroids(SPs) ,a family of chiral insecticides consisting of multiple stereoismers,have been regarded as estrogenic endocrine-disrupting chemicals(EDCs) .In this study,we applied the yeast two-hybrid and ...Synthetic pyrethroids(SPs) ,a family of chiral insecticides consisting of multiple stereoismers,have been regarded as estrogenic endocrine-disrupting chemicals(EDCs) .In this study,we applied the yeast two-hybrid and molecular docking(MD) assay to assess the enantioselective estrogenic activities of three commonly used SPs,bifenthrin(cis-BF) ,permethrin(PM) and fenvalerate(Fen) .The β-galactosidase analyses indicated that all of the testing pyrethroids displayed significant(p<0.05) enantioselectivity.The results showed that the estrogenic potential of cis-BF was mainly attributed to 1S-cis-BF.Neither PM nor Fen showed estrogenic effects.However,two stereoisomers of PM possessed estrogenic potential activities.αR-2R-Fen and αS-2S-Fen also induced the β-galactosidase activity.The inability to initiate the reporter gene expression by the racemic chemicals may be due to the low ratios of these isomers or the antagonism among them.The strong hydrophobic interaction and the hydrogen bond between positive estrogenic isomers and ERα support our biological testing results.This research demonstrated that the enantioselective estrogenic activity of chiral SPs was due to selective binding between their isomers and the ERαreceptor.The data suggests that enantioselectivity of these chiral pesticides is significant to their estrogenic activities.展开更多
In this study,a sensitive and rapid magnetic solid‑phase microextraction(MSPE)procedure based on Fe_(3)O_(4) nanoparticle‑modified,multi‑walled carbon nanotubes combined with a gas chromatography/electron capture dete...In this study,a sensitive and rapid magnetic solid‑phase microextraction(MSPE)procedure based on Fe_(3)O_(4) nanoparticle‑modified,multi‑walled carbon nanotubes combined with a gas chromatography/electron capture detector(GC/ECD)was developed to quantify pyrethroids in human blood samples.This study compared liquid-liquid extraction and solid‑phase extraction methods and found that the MSPE‑GC/ECD method had many advantages,such as high recovery rate,high extraction efficiency,high detection sensitivity,low limit of detection,and simple operation.It can meet the actual requirements for the determination of synthetic pyrethroids in human blood.展开更多
The red imported fire ant,Solenopsis invicta Buren,poses a significant threat to biodiversity,agriculture,and public health in its introduced ranges.While chemicals such as toxic baits and dust are the main methods fo...The red imported fire ant,Solenopsis invicta Buren,poses a significant threat to biodiversity,agriculture,and public health in its introduced ranges.While chemicals such as toxic baits and dust are the main methods for S.invicta control,toxic baits are slow,requiring approximately one or two weeks,but dust can eliminate the colony of fire ants rapidly in just three to five days.To explore more active ingredients for fire ant control using dusts,the toxicity of bifenthrin and dimefluthrin,the horizontal transfer of bifenthrin and dimefluthrin dust and their efficacy in the field were tested.The results showed that the LD50(lethal dose) values of bifenthrin and dimefluthrin were 3.40 and 1.57 ng/ant,respectively.The KT50(median knockdown time) and KT95(95%knockdown time) values of a 20μg mL^(–1)bifenthrin dose were 7.179and 16.611 min,respectively.The KT50and KT95of a 5μg mL^(–1)dimefluthrin dose were 1.538 and 2.825 min,respectively.The horizontal transfers of bifenthrin and dimefluthrin among workers were effective.The mortality of recipients (secondary mortality) and secondary recipients (tertiary mortality) were both over 80%at 48 h after 0.25,0.50 and 1.00%bifenthrin dust treatments.The secondary mortality of recipients was over 99%at 48 h after 0.25,0.50 and 1.00% dimefluthrin dust treatments,but the tertiary mortality was below 20%.The field trial results showed that both bifenthrin and dimefluthrin exhibited excellent fire ant control effects,and the comprehensive control effects of 1.00%bifenthrin and dimefluthrin dusts at 14 d post-treatment were 95.87 and 85.70%,respectively.展开更多
This review aimed to determine the prevalence of the insecticide resistance status of the field-collected Aedes(Ae.)aegypti and Ae.albopictus in Malaysia from 2010 to 2022 towards carbamates,organochlorines,organophos...This review aimed to determine the prevalence of the insecticide resistance status of the field-collected Aedes(Ae.)aegypti and Ae.albopictus in Malaysia from 2010 to 2022 towards carbamates,organochlorines,organophosphates and pyrethroids.Biological and environmental controls were summarized with an emphasis on the mosquito vector control strategies in Malaysia.The information in this review was extracted from several databases such as PubMed(MEDLINE),Science Direct and Scopus by using keywords including“insecticide resistance”,“carbamate resistance”,“organochlorine resistance”,“organophosphate resistance”,“pyrethroid resistance”,“Aedes”and“Malaysia”,between January 2022 and December 2022.Distribution of resistant Ae.aegypti and Ae.albopictus in Malaysia was mapped using QGIS software.Insecticide resistance in both Ae.aegypti and Ae.albopictus is widespread in Malaysia,although the rates vary by states.The most notable was the steep increase in permethrin resistance of Ae.aegypti in Selangor,Malaysia,over the past decade.Ae.albopictus also displayed moderate resistance to permethrin,though not as widespread as Ae.aegypti in Selangor,but showed sign of resistance in Sarawak,East Malaysia.Resistance towards four main classes of insecticides have been widely documented in Malaysia.The extensive resistance towards permethrin in Malaysia which is one of the current insecticides used in Malaysia suggested that policies supporting the widespread use of permethrin fogging needs further evaluation.展开更多
Alzheimer’s disease(AD)is a progressive and neurodegenerative illness which results in alterations in cognitive development.It is characterized by loss/dysfunction of cholinergic neurons,and formation of amyloid plaq...Alzheimer’s disease(AD)is a progressive and neurodegenerative illness which results in alterations in cognitive development.It is characterized by loss/dysfunction of cholinergic neurons,and formation of amyloid plaques,and formation of neurofibrillary tangles,among other changes,due to hyperphosphorylation of tau-protein.Exposure to pesticides in humans occurs frequently due to contact with contaminated food,water,or particles.Organochlorines,organophosphates,carbamates,pyrethroids and neonicotinoids are associated with the most diagnosed incidents of severe cognitive impairment.The aim of this study was to determine the effects of these pesticides on the phosphorylation of tau protein,and its cognitive implications in the development of AD.It was found that exposure to pesticides increased the phosphorylation of tau protein at sites Ser198,Ser199,Ser202,Thr205,Ser396 and Ser404.Contact with these chemicals altered the enzymatic activities of cyclin-dependent kinase 5 and glycogen synthase kinase 3 beta,and protein phosphatase-2A.Moreover,it altered the expression of the microtubule associated protein tau gene,and changed levels of intracellular calcium.These changes affected tau protein phosphorylation and neuroinflammation,and also increased oxidative stress.In addition,the exposed subjects had poor level of performance in tests that involved evaluation of novelty,as test on verbal,non-verbal,spatial memory,attention,and problem-solving skills.展开更多
Background: In lacustrine communities, whether in Benin or elsewhere, populations use impregnated mosquito nets (IMNs) as fishing nets. This depletes the lake of its fishery resources, which in turn are contaminated b...Background: In lacustrine communities, whether in Benin or elsewhere, populations use impregnated mosquito nets (IMNs) as fishing nets. This depletes the lake of its fishery resources, which in turn are contaminated by the pyrethroids impregnated in the nets. This study aims to determine the scale and factors associated with the use of pyrethroid-impregnated mosquito nets as fishing tools in the municipality of Sô-Ava in Benin. Methods: This is a cross-sectional and analytical study with two components. First, a quantitative component was made up of 280 volunteers who were interviewed in the seven districts of the city. Data collection was done in two phases: the first from September to October 2020, and the second in August 2022. Data were analyzed with Stata and logistic regression was used. Another qualitative component was made up of forty participants chosen by reasoned choice, of which 32 were split into four focus groups of eight members each, and the rest participated in semi-structured interviews. Triangulation of the different sources was used to analyze the data. Results: Around 67% of the population reported using impregnated mosquito nets as fishing tools and 33% exclusively for malaria. Seasonal fishermen (ORa = 2.03, CI = 1.35 - 4.97, P = 0.004) and years of professional experience (ORa = 1.53, CI = 1.00 - 2.05, P = 0.021) increase the risk of using these nets as fishing tools. The use of insecticide-treated mosquito nets against mosquitoes causes skin scratching and impairs breathing because of the impregnation products, as reported by respondents. Conclusion: A high prevalence of inappropriate use of impregnated mosquito nets in fishing practices is highlighted in this study. Interviews in the field revealed that nets are diverted for fishing purposes to increase the volume of catches. Consequently, it will be appropriate to assess the pyrethroid content in water and fishery products.展开更多
The widespread use of long-lasting insecticidal nets (LLINs) is a major intervention method for malaria control. While coverage of LLINs has increased, there is a need for information on the operational effectiveness ...The widespread use of long-lasting insecticidal nets (LLINs) is a major intervention method for malaria control. While coverage of LLINs has increased, there is a need for information on the operational effectiveness of nets deployed in the field in the context of malaria vector resistance to insecticides used for impregnation. The development of specific anti-malarial biomarkers to assess exposure to mosquito bites is an important development in evaluations. The aim of this study was to characterize the human IgG antibody response to Anopheles gSG6-P1 saliva, a salivary peptide antigen previously shown to be a relevant biomarker of human exposure to Anopheles bites, in order to assess the LLINs under field conditions in areas of low and high vector resistance to insecticides. We analyzed data from 240 randomly selected children ( 0.05). Furthermore, the same finding was observed for antibody expression in children whether or not they used LLINs on the day before the survey (p = 0.7724). Similarly, gender and especially age, major factors of variation in the adaptive immune response, did not have a significant effect on IgG expression.展开更多
A GC-MS method was established for determination of 10 pyrethroids in apple juice concentrate.The sample was extracted by acetone and hexane,and the 10 pyrethroids were separated on a capillary column(DB-5,30 m×2...A GC-MS method was established for determination of 10 pyrethroids in apple juice concentrate.The sample was extracted by acetone and hexane,and the 10 pyrethroids were separated on a capillary column(DB-5,30 m×250 μm×0.25 μm) and determined by GC-MSD.The recoveries of pyrethroids were range of 84%-96% with the detection limits of 3-46 μg/kg.The relative standard deviations were range of 0.68%-5.11%.展开更多
A GC-MS method for the determination of 27 organochlorine pesticides and 15 Pyrethroid pesticides in animal food is established.The method was based on Gel Permeation chromatography combined with solid-phase extractio...A GC-MS method for the determination of 27 organochlorine pesticides and 15 Pyrethroid pesticides in animal food is established.The method was based on Gel Permeation chromatography combined with solid-phase extraction for sample preparation.Rapid qualitative and quantitative analyses was carried out by gas chromatography-mass spectrometry under the selective-ion monitoring mode.The experimental results showed that the correlation coefficients were better than 0.99,the recoveries for spiked standards were 70%-104%,the relative standard deviations were 2.1%-15.9%.展开更多
Objective: To evaluate the susceptibility of Anopheles stephensi(An. stephensi) Liston, the main malaria vector in southern Iran, to WHO recommended insecticides. Methods: Larvae of An. stephensi were collected from t...Objective: To evaluate the susceptibility of Anopheles stephensi(An. stephensi) Liston, the main malaria vector in southern Iran, to WHO recommended insecticides. Methods: Larvae of An. stephensi were collected from three different larval habitats in both urban and rural area of Bandar Abbas city and one rural area in Rudan county southern Iran. WHO standard method was used for evaluation of adult and larval mosquito susceptibility. Bendiocarb, permethrin, lambda-cyhalothrin, deltamethrin as insecticide and temephos and chlorpyriphos as larvicide were used at the diagnostic dosages recommended by WHO. Results: Findings of this study showed all larval populations of An. stephensi were completely susceptible to temephos and candidate for resistance to chlorpyriphos. Adult mosquitoes in rural areas of Bandar Abbas city were resistant to pyrethroid and carbamate insecticides. Conclusion: Comparison of the results of this survey with previous studies indicates that the resistance to pyrethroids and carbamates in this malaria endemic region is increasing. Wide use of pesticides in agriculture is certainly effective in increasing resistance. The inter-sectoral coordination and collaboration in health and agriculture seem to be necessary to manage insecticide resistance in malaria vectors.展开更多
Most national malaria control programmes rely extensively on pyrethroid insecticides to control mosquito vectors of this disease. Unfortunately, the intensive use of this class of insecticides both in public health an...Most national malaria control programmes rely extensively on pyrethroid insecticides to control mosquito vectors of this disease. Unfortunately, the intensive use of this class of insecticides both in public health and agriculture has led to its reduced efficacy. The objective of this review was to assess the role of agricultural pesticides use on the development of resistance to insecticides in malaria vectors and the potential impact of this resistance on control activities. We searched library catalogues and public databases for studies that included data on resistance to the major classes of insecticides: organochlorines, carbamates, organophosphates and pyrethroids, in the malaria vectors of Anopheles genera. There is a strong geographical bias in published studies many originating from West African countries. Several studies demonstrate that resistance to pyrethroids is widespread in the major malaria vectors of the Anopheles gambiae and Anopheles funestus complexes. Assessing the impact of insecticide resistance on vector control is complicated owing to the lack of studies into the epidemiological consequences of resistance on the control of malaria and other vector borne diseases.展开更多
The low yield of food production ascribed to harm caused by pests has led to the application of pesticides to food crops. Pesticide residues from the application on crops are mostly found in foods that can cause disea...The low yield of food production ascribed to harm caused by pests has led to the application of pesticides to food crops. Pesticide residues from the application on crops are mostly found in foods that can cause diseases for consumers of such products. A total of 37 pesticide residues consisting of 15 organochlorines (OC), 13 organophosphorus (OP) and 9 synthetic pyrethroids (SP) were determined. The QuEChERS method was exploited for extraction and clean-up. Gas Chromatograph was used for detection and quantification which was equipped with an electron capture detector and pulse flame photometric detector. The results showed that the mean concentrations of pesticides in fish ranged from 0.007 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> to 1.026 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> for OCs, 0.002 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> to 0.190 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> for OPs and 0.004 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> to 0.032 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> for SP. Sediments have mean concentrations ranged from 0.005 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> to 1.207 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> for OCs. OP ranges from 0.002 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> to 0.399 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> and 0.003 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> to 0.202 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> for synthetic pyrethroids. Maximum Residue Limits were exceeded in both fish and sediment samples except for malathion, fenitrothion, profenofos, gamma-chlordane, and deltamethrin. Exposure in children ranged from 4.60 × 10<sup>-6</sup> mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup><span style="white-space:nowrap;">·</span>d<sup>-1</sup> to 2.36 × 10<sup>-3</sup> mg·kg<sup>-1</sup><span style="white-space:nowrap;">·</span>d<sup>-1</sup> and in adults it is from 1.97 × 10<sup>-6</sup> mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup><span style="white-space:nowrap;">·</span>d<sup>-1</sup> to 1.01 × 10<sup>-3</sup> mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup><span style="white-space:nowrap;">·</span>d<sup>-1</sup>. Health risk estimation revealed a non-cancer risk potential of β-HCH in sediment and aldrin and p,p'-DDE in fish. Carcinogenic risk assessed for organochlorine pesticide residues indicates cancer benchmark concentrations greater than 10<sup>-4</sup> to 10<sup>-6</sup> threshold for acceptance.展开更多
Objective: To investigate the susceptibility to some conventional and non-conventional insecticides in laboratory and field larval populations of the West Nile vector Culex pipiens L.(Cx. pipiens), the dominant specie...Objective: To investigate the susceptibility to some conventional and non-conventional insecticides in laboratory and field larval populations of the West Nile vector Culex pipiens L.(Cx. pipiens), the dominant species in Jeddah Province, Saudi Arabia.Methods: The tested conventional insecticides were Actikil and Pesgard, while the nonconventional ones were Bacilod, Dudim and Baycidal. Probit analysis and photomicroscopical observations were carried out to shed light on acute toxicity in laboratory and field Cx. pipiens strains.Results: Cx. pipiens were more susceptible to Pesgard(LC50: 0.045 and 0.032 mg/L)than Actikil(0.052 and 0.038 mg/L) and Bacilod(0.129 and 0.104 mg/L), for the field and laboratory strains, respectively. Results showed that treatments with the chitin synthesis inhibitor Dudim and Baycidal evoked morphological effects similar to those induced by other insect growth regulators. According to IC50 values obtained(concentration which to inhibit the emergence of 50% of mosquito adults), the compound Dudim(0.000 3 and 0.000 1 mg/L) was more effective against Cx. pipiens L. mosquitoes than Baycidal(0.000 4 and 0.000 3 mg/L) for both the field and laboratory strains, respectively.Conclusions: Our results provide baseline data to enhance control programs and orient public health decisions on the selection of pesticides against mosquito vectors in Saudi Arabia.展开更多
Considering the potential pesticide side effects on environment, their short and long term untoward effects on living creatures, their excessive usage for producing more agricultural products, and also their applicati...Considering the potential pesticide side effects on environment, their short and long term untoward effects on living creatures, their excessive usage for producing more agricultural products, and also their application to destroy pests of any sort, the present study was carried out to investigate the used amount of common pesticides in Iran markets. A questionnaire was designed. Referring to pesticide selling shops and plants preservations organizations in Tehran and Isfahan, the sufficient data was collected and then categorized regarding the applications and the total amount of used pesticides in a year. The results demonstrated that there were 60 sorts of used pesticides in Iran. They included Organochlorine (10%), Organophosphorus (28.4%), Pyrethroids derivatives (10%), Carbamate derivatives (10%), and others (41.6%). The commonest pesticide used in a year was Organophosphorus and the least one was Organochlorine. The obtained data pointed out that the most common pesticide was Organophosphorus. Given that Organophosphorine compounds are poisonous in living creatures and cause short and long term side effects. It is recommended that responsible authorities provide the necessary information for the aimed groups in terms of the allowable using amount of pesticides, the protection strategies and the pesticides hazards on users.展开更多
基金supported by the Council of the Advancement of Pyrethroid Human Risk Assessment(CAPHRA)(#S17110000000004).
文摘Microtransplantation of rat brain neurolemma into the plasma membrane of Xenopus laevis oocytes is an ex vivo method used to study channels and receptors in their native state using standard electrophysiological approaches.In this review,we show that oocytes injected with adult rat brain neurolemma elicited tetrodotoxin-sensitive inward ion currents upon membrane depolarization,which were increased in a concentration-dependent manner by treatment with the pyrethroid insecticides permethrin and deltamethrin.Under our initial protocols,oocyte health was reduced over time and neurolemma incorporation varied between batches of oocytes from different frogs,limiting the usefulness of the assay for regulatory issues.A collection of changes to the assay procedure,data acceptance criteria,and analysis method yield substantially improved precision and,hence,assay performance.These changes established this ex vivo approach as a toxicologically relevant assay to study the toxicodynamic action of pyrethroids on ion channels in their native state using neurolemma fragments prepared from juvenile and adult rat brains.
文摘Of the tumors diagnosed in the female dogs have the highest mammary neoplasias incidence. These neoplasias can be influenced by environmental contaminants. Despite evidence of pyrethroid toxicity, carcinogenic potential has not yet been sufficiently elucidated, there is a need to investigate their involvement in mammary tumor. In previous studies, pyrethroid residues were detected in female dogs with mammary neoplasia, however was not investigate the influence of this insecticide in the genesis and aggressiveness of mammary cancer. This study aimed to investigate possible relations between pyrethroid residues and aggressiveness of mammary carcinoma in female dogs. Fifty selected female dogs were divided into five groups of 10 animals each: the Control group, female dogs without mammary neoplasia;the groups Luminal A, Luminal B, HER-2 Superexpression and Basal were constituted by female dogs that presented inguinal mammary carcinoma classified immunohistochemically. The aggressiveness of carcinomas was evaluated by immunohistochemistry (HER-2, p63, estrogen receptor). Residual concentrations of the pyrethroids from the mammary gland and fat tissue adjacent to it were determined by HPLC. Data were analyzed by Chi-Square test. Of the all animals, six presented residues of pyrethroids in mammary samples and 10 presented it in fat tissue samples. There was no statistical evidence that pyrethroids are involved in mammary carcinoma aggressiveness in female dogs.
文摘Diagnosis and biological behavior of breast cancer of female dog represent one of the biggest challenges facing the Veterinarian in recent years. Due to its exponential growth and the degree of aggressiveness, the exact cause of this tumor is probably multifactorial and it is believed that may suffer influence from environmental factors. Among the suspected environmental contaminants are the pyrethroids. Aiming to investigate the participation of pyrethroids in tumorigenesis in female dogs, a study was conducted using 50 female dogs, 22 were positive for simple breast carcinoma (Group I), 18 with a diagnosis of complex breast carcinoma (Group II) and 10 negative (Group III) for breast cancer. In order to detect DNA damage, the Comet assay was performed on mammary samples of these animals, which also had samples submitted to the technique of High Performance Liquid Chromatography (HPLC), which aimed to quantify the concentration of pyrethroids. The results of HPLC of each animal were compared with those obtained by the Comet assay analysis of variance and the means were compared by the test groups “Student T” at the significance level of p ￡ 0.05. Despite presenting correlation between the amount of DNA damage and tumor aggressiveness, no statistical differences were found in the DNA damage of different histologic types of breast carcinoma. As for pyrethroids, even these were detected in 22% of tumor tissues and peritumoral fat, there was no difference in DNA damage between cells exposed and not exposed to environmental contaminant.
基金the financial and technology support of State Key Lab of Food Science and Technology of Nanchang University(SKLF-ZZA-201910).
文摘Pyrethroid is widely used in developing countries and is a potential threat to human health.So putting forward an effective pyrethroid cleaning method is of vital importance.Clearance of fenpropathrin,cypermethrin and deltamethrin in cabbage by using ultrasonic treatment accompanied with different baking soda concentrations were investigated in this study.The results of response surface methodology showed that the maximum clearance rate was 70.61% for fenpropathrin under the optimal power,treated time,treated temperature and baking soda concentration,which were 260.02 W,10 min,20.15◦C and 0.014 g/mL,respectively.Similarly,the maximum removal efficiency was 73.72% for cypermethrin under 240 W,13.84 min,19.53℃ and 0.014 g/mL,and 92.15%for deltamethrin under 238.99 W,12.42 min,25℃ and 0.013 g/mL.The clearance rate of pyrethroid by this method was significant higher(P<0.05)than traditional cleaning methods(bathing and running water washing).The contents of the compositions such as vitamin C,total soluble sugar,protein and dietary fiber,texture and sensory evaluation of cabbage were not found obvious changes after the ultrasonic treatment combined with baking soda(P>0.05).Results showed that ultrasonic treatment combined with baking soda was an effective way to eliminate the fenpropathrin,cypermethrin and deltamethrin in cabbage without influencing cabbage quality.
基金Supported by Standard Project of State Tobacco Monopoly Administration(2014B023)
文摘[Objective] In order to provide a reference for safe and reasonable use of pyrethroids in cigarette production,the degradation behaviors of three kinds of pyrethroids in cigarette production environment were studied. [Method]Three kinds of pyrethroids( permethrin,cyfluthrin and cis-cypermethrin) were administrated to two media( cut tobacco and iron sheet surface) in cigarette production environment at MRLs concentration,and the first sampling was conducted at 24 d post administration. Afterwards,sampling was performed once every 7 d,with a total of six times. The degradation rates of insecticides in different media were calculated,and degradation models were established. [Result] The contents of three kinds of insecticides in two media gradually declined with the prolongation of time,and degradation rates presented the trend of fast-slow-fast; the degradation rates of permethrin,cyfluthrin and cis-cypermethrin in cut tobacco at 36 d post administration were 97. 14%,88. 89% and 95. 38%,respectively; the degradation rates on iron sheet surface were 29. 95%,48. 99% and 40. 24%,respectively.The half lives of three kinds of insecticides in cut tobacco were 1- 2 d,while those on iron sheet surface were 6- 10 d. [Conclusion]The contents of three kinds of insecticides in two media gradually declined with the prolongation of time,and their degradation regularity accorded with first order kinetic equation.
基金support from the National Natural Science Foundation of China(20837002 & 20877071)the National Basic Research Program of China(2009CB421603)
文摘Synthetic pyrethroids(SPs) ,a family of chiral insecticides consisting of multiple stereoismers,have been regarded as estrogenic endocrine-disrupting chemicals(EDCs) .In this study,we applied the yeast two-hybrid and molecular docking(MD) assay to assess the enantioselective estrogenic activities of three commonly used SPs,bifenthrin(cis-BF) ,permethrin(PM) and fenvalerate(Fen) .The β-galactosidase analyses indicated that all of the testing pyrethroids displayed significant(p<0.05) enantioselectivity.The results showed that the estrogenic potential of cis-BF was mainly attributed to 1S-cis-BF.Neither PM nor Fen showed estrogenic effects.However,two stereoisomers of PM possessed estrogenic potential activities.αR-2R-Fen and αS-2S-Fen also induced the β-galactosidase activity.The inability to initiate the reporter gene expression by the racemic chemicals may be due to the low ratios of these isomers or the antagonism among them.The strong hydrophobic interaction and the hydrogen bond between positive estrogenic isomers and ERα support our biological testing results.This research demonstrated that the enantioselective estrogenic activity of chiral SPs was due to selective binding between their isomers and the ERαreceptor.The data suggests that enantioselectivity of these chiral pesticides is significant to their estrogenic activities.
文摘In this study,a sensitive and rapid magnetic solid‑phase microextraction(MSPE)procedure based on Fe_(3)O_(4) nanoparticle‑modified,multi‑walled carbon nanotubes combined with a gas chromatography/electron capture detector(GC/ECD)was developed to quantify pyrethroids in human blood samples.This study compared liquid-liquid extraction and solid‑phase extraction methods and found that the MSPE‑GC/ECD method had many advantages,such as high recovery rate,high extraction efficiency,high detection sensitivity,low limit of detection,and simple operation.It can meet the actual requirements for the determination of synthetic pyrethroids in human blood.
基金supported by the Special Project for Sustainable Development Science and Technology of Shenzhen, China (2021N007)the Special Project for Red Imported Fire Ant Management, Shenzhen Agricultural Science and Technology Promotion Center, China (20220900044zbzjbc)。
文摘The red imported fire ant,Solenopsis invicta Buren,poses a significant threat to biodiversity,agriculture,and public health in its introduced ranges.While chemicals such as toxic baits and dust are the main methods for S.invicta control,toxic baits are slow,requiring approximately one or two weeks,but dust can eliminate the colony of fire ants rapidly in just three to five days.To explore more active ingredients for fire ant control using dusts,the toxicity of bifenthrin and dimefluthrin,the horizontal transfer of bifenthrin and dimefluthrin dust and their efficacy in the field were tested.The results showed that the LD50(lethal dose) values of bifenthrin and dimefluthrin were 3.40 and 1.57 ng/ant,respectively.The KT50(median knockdown time) and KT95(95%knockdown time) values of a 20μg mL^(–1)bifenthrin dose were 7.179and 16.611 min,respectively.The KT50and KT95of a 5μg mL^(–1)dimefluthrin dose were 1.538 and 2.825 min,respectively.The horizontal transfers of bifenthrin and dimefluthrin among workers were effective.The mortality of recipients (secondary mortality) and secondary recipients (tertiary mortality) were both over 80%at 48 h after 0.25,0.50 and 1.00%bifenthrin dust treatments.The secondary mortality of recipients was over 99%at 48 h after 0.25,0.50 and 1.00% dimefluthrin dust treatments,but the tertiary mortality was below 20%.The field trial results showed that both bifenthrin and dimefluthrin exhibited excellent fire ant control effects,and the comprehensive control effects of 1.00%bifenthrin and dimefluthrin dusts at 14 d post-treatment were 95.87 and 85.70%,respectively.
基金support from Ministry of Higher Education Malaysia for funding Fundamental Research Grant Scheme FRGS 2020-1 (FRGS/1/2020/WAB02/MSU/02/1)Management and Science University for funding Seed Research Grant Phase 1/2020 (SG-008-012020-FHLS).
文摘This review aimed to determine the prevalence of the insecticide resistance status of the field-collected Aedes(Ae.)aegypti and Ae.albopictus in Malaysia from 2010 to 2022 towards carbamates,organochlorines,organophosphates and pyrethroids.Biological and environmental controls were summarized with an emphasis on the mosquito vector control strategies in Malaysia.The information in this review was extracted from several databases such as PubMed(MEDLINE),Science Direct and Scopus by using keywords including“insecticide resistance”,“carbamate resistance”,“organochlorine resistance”,“organophosphate resistance”,“pyrethroid resistance”,“Aedes”and“Malaysia”,between January 2022 and December 2022.Distribution of resistant Ae.aegypti and Ae.albopictus in Malaysia was mapped using QGIS software.Insecticide resistance in both Ae.aegypti and Ae.albopictus is widespread in Malaysia,although the rates vary by states.The most notable was the steep increase in permethrin resistance of Ae.aegypti in Selangor,Malaysia,over the past decade.Ae.albopictus also displayed moderate resistance to permethrin,though not as widespread as Ae.aegypti in Selangor,but showed sign of resistance in Sarawak,East Malaysia.Resistance towards four main classes of insecticides have been widely documented in Malaysia.The extensive resistance towards permethrin in Malaysia which is one of the current insecticides used in Malaysia suggested that policies supporting the widespread use of permethrin fogging needs further evaluation.
文摘Alzheimer’s disease(AD)is a progressive and neurodegenerative illness which results in alterations in cognitive development.It is characterized by loss/dysfunction of cholinergic neurons,and formation of amyloid plaques,and formation of neurofibrillary tangles,among other changes,due to hyperphosphorylation of tau-protein.Exposure to pesticides in humans occurs frequently due to contact with contaminated food,water,or particles.Organochlorines,organophosphates,carbamates,pyrethroids and neonicotinoids are associated with the most diagnosed incidents of severe cognitive impairment.The aim of this study was to determine the effects of these pesticides on the phosphorylation of tau protein,and its cognitive implications in the development of AD.It was found that exposure to pesticides increased the phosphorylation of tau protein at sites Ser198,Ser199,Ser202,Thr205,Ser396 and Ser404.Contact with these chemicals altered the enzymatic activities of cyclin-dependent kinase 5 and glycogen synthase kinase 3 beta,and protein phosphatase-2A.Moreover,it altered the expression of the microtubule associated protein tau gene,and changed levels of intracellular calcium.These changes affected tau protein phosphorylation and neuroinflammation,and also increased oxidative stress.In addition,the exposed subjects had poor level of performance in tests that involved evaluation of novelty,as test on verbal,non-verbal,spatial memory,attention,and problem-solving skills.
文摘Background: In lacustrine communities, whether in Benin or elsewhere, populations use impregnated mosquito nets (IMNs) as fishing nets. This depletes the lake of its fishery resources, which in turn are contaminated by the pyrethroids impregnated in the nets. This study aims to determine the scale and factors associated with the use of pyrethroid-impregnated mosquito nets as fishing tools in the municipality of Sô-Ava in Benin. Methods: This is a cross-sectional and analytical study with two components. First, a quantitative component was made up of 280 volunteers who were interviewed in the seven districts of the city. Data collection was done in two phases: the first from September to October 2020, and the second in August 2022. Data were analyzed with Stata and logistic regression was used. Another qualitative component was made up of forty participants chosen by reasoned choice, of which 32 were split into four focus groups of eight members each, and the rest participated in semi-structured interviews. Triangulation of the different sources was used to analyze the data. Results: Around 67% of the population reported using impregnated mosquito nets as fishing tools and 33% exclusively for malaria. Seasonal fishermen (ORa = 2.03, CI = 1.35 - 4.97, P = 0.004) and years of professional experience (ORa = 1.53, CI = 1.00 - 2.05, P = 0.021) increase the risk of using these nets as fishing tools. The use of insecticide-treated mosquito nets against mosquitoes causes skin scratching and impairs breathing because of the impregnation products, as reported by respondents. Conclusion: A high prevalence of inappropriate use of impregnated mosquito nets in fishing practices is highlighted in this study. Interviews in the field revealed that nets are diverted for fishing purposes to increase the volume of catches. Consequently, it will be appropriate to assess the pyrethroid content in water and fishery products.
文摘The widespread use of long-lasting insecticidal nets (LLINs) is a major intervention method for malaria control. While coverage of LLINs has increased, there is a need for information on the operational effectiveness of nets deployed in the field in the context of malaria vector resistance to insecticides used for impregnation. The development of specific anti-malarial biomarkers to assess exposure to mosquito bites is an important development in evaluations. The aim of this study was to characterize the human IgG antibody response to Anopheles gSG6-P1 saliva, a salivary peptide antigen previously shown to be a relevant biomarker of human exposure to Anopheles bites, in order to assess the LLINs under field conditions in areas of low and high vector resistance to insecticides. We analyzed data from 240 randomly selected children ( 0.05). Furthermore, the same finding was observed for antibody expression in children whether or not they used LLINs on the day before the survey (p = 0.7724). Similarly, gender and especially age, major factors of variation in the adaptive immune response, did not have a significant effect on IgG expression.
文摘A GC-MS method was established for determination of 10 pyrethroids in apple juice concentrate.The sample was extracted by acetone and hexane,and the 10 pyrethroids were separated on a capillary column(DB-5,30 m×250 μm×0.25 μm) and determined by GC-MSD.The recoveries of pyrethroids were range of 84%-96% with the detection limits of 3-46 μg/kg.The relative standard deviations were range of 0.68%-5.11%.
文摘A GC-MS method for the determination of 27 organochlorine pesticides and 15 Pyrethroid pesticides in animal food is established.The method was based on Gel Permeation chromatography combined with solid-phase extraction for sample preparation.Rapid qualitative and quantitative analyses was carried out by gas chromatography-mass spectrometry under the selective-ion monitoring mode.The experimental results showed that the correlation coefficients were better than 0.99,the recoveries for spiked standards were 70%-104%,the relative standard deviations were 2.1%-15.9%.
基金financially supported by deputy for research,Tehran University of Medical Sciences,Project No.36251
文摘Objective: To evaluate the susceptibility of Anopheles stephensi(An. stephensi) Liston, the main malaria vector in southern Iran, to WHO recommended insecticides. Methods: Larvae of An. stephensi were collected from three different larval habitats in both urban and rural area of Bandar Abbas city and one rural area in Rudan county southern Iran. WHO standard method was used for evaluation of adult and larval mosquito susceptibility. Bendiocarb, permethrin, lambda-cyhalothrin, deltamethrin as insecticide and temephos and chlorpyriphos as larvicide were used at the diagnostic dosages recommended by WHO. Results: Findings of this study showed all larval populations of An. stephensi were completely susceptible to temephos and candidate for resistance to chlorpyriphos. Adult mosquitoes in rural areas of Bandar Abbas city were resistant to pyrethroid and carbamate insecticides. Conclusion: Comparison of the results of this survey with previous studies indicates that the resistance to pyrethroids and carbamates in this malaria endemic region is increasing. Wide use of pesticides in agriculture is certainly effective in increasing resistance. The inter-sectoral coordination and collaboration in health and agriculture seem to be necessary to manage insecticide resistance in malaria vectors.
文摘Most national malaria control programmes rely extensively on pyrethroid insecticides to control mosquito vectors of this disease. Unfortunately, the intensive use of this class of insecticides both in public health and agriculture has led to its reduced efficacy. The objective of this review was to assess the role of agricultural pesticides use on the development of resistance to insecticides in malaria vectors and the potential impact of this resistance on control activities. We searched library catalogues and public databases for studies that included data on resistance to the major classes of insecticides: organochlorines, carbamates, organophosphates and pyrethroids, in the malaria vectors of Anopheles genera. There is a strong geographical bias in published studies many originating from West African countries. Several studies demonstrate that resistance to pyrethroids is widespread in the major malaria vectors of the Anopheles gambiae and Anopheles funestus complexes. Assessing the impact of insecticide resistance on vector control is complicated owing to the lack of studies into the epidemiological consequences of resistance on the control of malaria and other vector borne diseases.
文摘The low yield of food production ascribed to harm caused by pests has led to the application of pesticides to food crops. Pesticide residues from the application on crops are mostly found in foods that can cause diseases for consumers of such products. A total of 37 pesticide residues consisting of 15 organochlorines (OC), 13 organophosphorus (OP) and 9 synthetic pyrethroids (SP) were determined. The QuEChERS method was exploited for extraction and clean-up. Gas Chromatograph was used for detection and quantification which was equipped with an electron capture detector and pulse flame photometric detector. The results showed that the mean concentrations of pesticides in fish ranged from 0.007 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> to 1.026 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> for OCs, 0.002 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> to 0.190 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> for OPs and 0.004 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> to 0.032 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> for SP. Sediments have mean concentrations ranged from 0.005 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> to 1.207 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> for OCs. OP ranges from 0.002 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> to 0.399 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> and 0.003 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> to 0.202 mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup> for synthetic pyrethroids. Maximum Residue Limits were exceeded in both fish and sediment samples except for malathion, fenitrothion, profenofos, gamma-chlordane, and deltamethrin. Exposure in children ranged from 4.60 × 10<sup>-6</sup> mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup><span style="white-space:nowrap;">·</span>d<sup>-1</sup> to 2.36 × 10<sup>-3</sup> mg·kg<sup>-1</sup><span style="white-space:nowrap;">·</span>d<sup>-1</sup> and in adults it is from 1.97 × 10<sup>-6</sup> mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup><span style="white-space:nowrap;">·</span>d<sup>-1</sup> to 1.01 × 10<sup>-3</sup> mg<span style="white-space:nowrap;">·</span>kg<sup>-1</sup><span style="white-space:nowrap;">·</span>d<sup>-1</sup>. Health risk estimation revealed a non-cancer risk potential of β-HCH in sediment and aldrin and p,p'-DDE in fish. Carcinogenic risk assessed for organochlorine pesticide residues indicates cancer benchmark concentrations greater than 10<sup>-4</sup> to 10<sup>-6</sup> threshold for acceptance.
基金Entomology and Toxicology Unit,University of Tabuk,Saudi Arabia with Grant No.1/1/11/1435
文摘Objective: To investigate the susceptibility to some conventional and non-conventional insecticides in laboratory and field larval populations of the West Nile vector Culex pipiens L.(Cx. pipiens), the dominant species in Jeddah Province, Saudi Arabia.Methods: The tested conventional insecticides were Actikil and Pesgard, while the nonconventional ones were Bacilod, Dudim and Baycidal. Probit analysis and photomicroscopical observations were carried out to shed light on acute toxicity in laboratory and field Cx. pipiens strains.Results: Cx. pipiens were more susceptible to Pesgard(LC50: 0.045 and 0.032 mg/L)than Actikil(0.052 and 0.038 mg/L) and Bacilod(0.129 and 0.104 mg/L), for the field and laboratory strains, respectively. Results showed that treatments with the chitin synthesis inhibitor Dudim and Baycidal evoked morphological effects similar to those induced by other insect growth regulators. According to IC50 values obtained(concentration which to inhibit the emergence of 50% of mosquito adults), the compound Dudim(0.000 3 and 0.000 1 mg/L) was more effective against Cx. pipiens L. mosquitoes than Baycidal(0.000 4 and 0.000 3 mg/L) for both the field and laboratory strains, respectively.Conclusions: Our results provide baseline data to enhance control programs and orient public health decisions on the selection of pesticides against mosquito vectors in Saudi Arabia.
文摘Considering the potential pesticide side effects on environment, their short and long term untoward effects on living creatures, their excessive usage for producing more agricultural products, and also their application to destroy pests of any sort, the present study was carried out to investigate the used amount of common pesticides in Iran markets. A questionnaire was designed. Referring to pesticide selling shops and plants preservations organizations in Tehran and Isfahan, the sufficient data was collected and then categorized regarding the applications and the total amount of used pesticides in a year. The results demonstrated that there were 60 sorts of used pesticides in Iran. They included Organochlorine (10%), Organophosphorus (28.4%), Pyrethroids derivatives (10%), Carbamate derivatives (10%), and others (41.6%). The commonest pesticide used in a year was Organophosphorus and the least one was Organochlorine. The obtained data pointed out that the most common pesticide was Organophosphorus. Given that Organophosphorine compounds are poisonous in living creatures and cause short and long term side effects. It is recommended that responsible authorities provide the necessary information for the aimed groups in terms of the allowable using amount of pesticides, the protection strategies and the pesticides hazards on users.
