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1.
Pestic Biochem Physiol ; 200: 105829, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38582575

RESUMO

Cowpea weevil, Callosobruchus maculatus, is the primary pest of stored cowpea seeds. The management of this infestation currently relies on insecticides, resulting in environmental pollution and selection of insecticide-resistant pests. Consequently, research efforts are being devoted to identify natural insecticides as sustainable and environment friendly alternatives for the control of C. maculatus. In this study, we explore the toxic effects of the nonhost seeds Parkia multijuga, Copaifera langsdorffii, Ormosia arborea, Amburana cearensis, Lonchocarpus guilleminianus, Sapindus saponaria, and Myroxylon peruiferum, on the cowpea weevil C. maculatus. Notably, all nonhost seeds led to reductions between 60 and 100% in oviposition by C. maculatus females. Additionally, the larvae were unable to penetrate the nonhost seeds. Artificial seeds containing 0.05% to 10% of cotyledon flour were toxic to C. maculatus larvae. Approximately 40% of larvae that consumed seeds containing 0.05% of O. arborea failed to develop, in contrast to control larvae. Proteomic analysis of A. cearensis and O. arborea seeds identify revealed a total of 371 proteins. From those, 237 are present in both seeds, 91 were exclusive to O. arborea seeds, and 43 were specific to A. cearensis seeds. Some of these proteins are related to defense, such as proteins containing the cupin domain and 11S seed storage protein. The in silico docking of cupin domain-containing proteins and 11S storage protein with N-acetylglucosamine (NAG)4 showed negative values of affinity energy, indicating spontaneous binding. These results showed that nonhost seeds have natural insecticide compounds with potential to control C. maculatus infestation.


Assuntos
Besouros , Inseticidas , Vigna , Gorgulhos , Animais , Feminino , Inseticidas/toxicidade , Proteômica , Larva , Sementes/química
2.
Pestic Biochem Physiol ; 200: 105827, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38582591

RESUMO

In addition to the acute lethal toxicity, insecticides might affect population dynamics of insect pests by inducing life history trait changes under low concentrations, however, the underlying mechanisms remain not well understood. Here we examined systemic impacts on development and reproduction caused by low concentration exposures to cyantraniliprole in the fall armyworm (FAW), Spodoptera frugiperda, and the putative underlying mechanisms were investigated. The results showed that exposure of third-instar larvae to LC10 and LC30 of cyantraniliprole significantly extended larvae duration by 1.46 and 5.41 days, respectively. Treatment with LC30 of cyantraniliprole significantly decreased the pupae weight and pupation rate as well as the longevity, fecundity and egg hatchability of female adults. Consistently, we found that exposure of FAW to LC30 cyantraniliprole downregulated the mRNA expression of four ecdysteroid biosynthesis genes including SfNobo, SfShd, SfSpo and SfDib and one ecdysone response gene SfE75 in the larvae as well as the gene encoding vitellogenin (SfVg) in the female adults. We also found that treatment with LC30 of cyantraniliprole significantly decreased the whole body levels of glucose, trehalose, glycogen and triglyceride in the larvae. Our results indicate that low concentration of cyantraniliprole inhibited FAW development by disruption of ecdysteroid biosynthesis as well as carbohydrate and lipid metabolism, which have applied implications for the control of FAW.


Assuntos
Ecdisteroides , Inseticidas , Pirazóis , ortoaminobenzoatos , Animais , Spodoptera , Metabolismo dos Lipídeos , Larva , Inseticidas/toxicidade , Carboidratos
3.
Pestic Biochem Physiol ; 200: 105837, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38582599

RESUMO

Susceptibility to insecticides is one of the limiting factors preventing wider adoption of natural enemies to control insect pest populations. Identification and selective breeding of insecticide tolerant strains of commercially used biological control agents (BCAs) is one of the approaches to overcome this constraint. Although a number of beneficial insects have been selected for increased tolerance to insecticides the molecular mechanisms underpinning these shifts in tolerance are not well characterised. Here we investigated the molecular mechanisms of enhanced tolerance of a lab selected strain of Orius laevigatus (Fieber) to the commonly used biopesticide spinosad. Transcriptomic analysis showed that spinosad tolerance is not a result of overexpressed detoxification genes. Molecular analysis of the target site for spinosyns, the nicotinic acetylcholine receptor (nAChR), revealed increased expression of truncated transcripts of the nAChR α6 subunit in the spinosad selected strain, a mechanism of resistance which was described previously in insect pest species. Collectively, our results demonstrate the mechanisms by which some beneficial biological control agents can evolve insecticide tolerance and will inform the development and deployment of insecticide-tolerant natural enemies in integrated pest management strategies.


Assuntos
Inseticidas , Receptores Nicotínicos , Tisanópteros , Animais , Tisanópteros/metabolismo , Inseticidas/toxicidade , Resistência a Inseticidas/genética , Agentes de Controle Biológico/farmacologia , Receptores Nicotínicos/genética , Receptores Nicotínicos/metabolismo , Insetos/genética , Macrolídeos/farmacologia , Combinação de Medicamentos
4.
Pestic Biochem Physiol ; 200: 105843, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38582603

RESUMO

Isoxazoline is a novel structure with strong potential for controlling agricultural insect pests, but its high toxicity to honeybees limits its development in agriculture. Herein, a series of N-phenylamide isoxazoline derivatives with low honeybee toxicity were designed and synthesized using the intermediate derivatization method. Bioassay results showed that these compounds exhibited good insecticidal activity. Compounds 3b and 3f showed significant insecticidal effects against Plutella xylostella (P. xylostella) with median lethal concentrations (LC50) of 0.06 and 0.07 mg/L, respectively, comparable to that of fluralaner (LC50 = 0.02 mg/L) and exceeding that of commercial insecticide fluxametamide (LC50 = 0.52 mg/L). It is noteworthy that the acute honeybee toxicities of compounds 3b and 3f (LD50 = 1.43 and 1.63 µg/adult, respectively) were significantly reduced to 1/10 of that of fluralaner (LD50 = 0.14 µg/adult), and were adequate or lower than that of fluxametamide (LD50 = 1.14 µg/adult). Theoretical simulation using molecular docking indicates that compound 3b has similar binding modes with fluralaner and a similar optimal docking pose with fluxametamide when binding to the GABA receptor, which may contribute to its potent insecticidal activity and relatively low toxicity to honey bees. This study provides compounds 3b and 3f as potential new insecticide candidates and provides insights into the development of new isoxazoline insecticides exhibiting both high efficacy and environmental safety.


Assuntos
Inseticidas , Mariposas , Abelhas , Animais , Inseticidas/toxicidade , Inseticidas/química , Simulação de Acoplamento Molecular , Insetos , Receptores de GABA/metabolismo , Amidas/toxicidade , Mariposas/metabolismo
5.
Sci Rep ; 14(1): 8291, 2024 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594566

RESUMO

Neonicotinoids (NEOs) have been designed to act selectively on insect nicotinic acetylcholine receptors (nAChRs). However, nAChRs are also expressed in vertebrate immune cells, so NEOs may interfere with the immune system in exposed non-target animals. The present study shows that NEOs: imidacloprid and thiacloprid, and their main metabolites: desnitro-imidacloprid and thiacloprid amide, at sub-micromolar concentrations ranging from 2.25 to 20 µM, affect the immune cells of fish. This was found both in primary cultures of leukocytes isolated from the carp head kidney and in the continuous adherent carp monocyte/macrophage cell line. Moreover, the results revealed that the studied pesticides and metabolites generate oxidative stress in carp immune cells and that this is one of the most important mechanisms of neonicotinoid immunotoxicity. Significant increases were observed in the formation of ROS and malondialdehyde (MDA). The antioxidant status alteration was linked with decrease in antioxidant enzyme activity: superoxide dismutase (SOD), catalase (CAT), and non-enzymatic antioxidant glutathione (GSH). Importantly, the metabolites: desnitro-imidacloprid and thiacloprid amide showed significantly higher cytotoxicity towards fish leukocytes than their parent compounds, imidacloprid and thiacloprid, which emphasizes the importance of including intermediate metabolites in toxicology studies.


Assuntos
Carpas , Inseticidas , Receptores Nicotínicos , Tiazinas , Animais , Inseticidas/toxicidade , Carpas/metabolismo , Antioxidantes/metabolismo , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Estresse Oxidativo , Receptores Nicotínicos/metabolismo , Leucócitos/metabolismo , Amidas
6.
Pestic Biochem Physiol ; 199: 105766, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38458675

RESUMO

Bemisia tabaci (Gennadius) is one of the most dangerous polyphagous pests in the world causing damage to various crops by sucking sap during the nymphal and adult stages. Chemical management of whiteflies is challenging because of the emergence of pesticide resistance. RNA interference has been well established in whitefly to study the functions of various genes. G-protein coupled receptors (GPCRs) are important targets for development of new generation insecticides. In this study, Ecdysis triggering hormone receptor (ETHr) gene expression was recorded in different stages of whitefly and its function has been studied through RNAi. The expression of ETHr is highest in third-instar nymphs followed by other nymphal instars, pupae and newly emerged adults. Silencing of ETHr resulted in significantly higher adult mortality (68.88%), reduced fecundity (4.46 eggs /female), reduced longevity of male and female (1.05 and 1.40 days, respectively) when adults were fed with dsETHr @ 1.0 µg/µl. Silencing of ETHr in nymphs lead to significantly higher mortality (81.35%) as compared to control. This study confirms that ETHr gene is essential for growth and development of whitefly nymphs and adults. Hence, it can be future target for developing dsRNA based insecticides for management of whitefly.


Assuntos
Hemípteros , Inseticidas , Animais , Inseticidas/toxicidade , Inseticidas/metabolismo , Muda/genética , Reprodução/genética , Hormônios/metabolismo , Hemípteros/fisiologia
7.
Pestic Biochem Physiol ; 199: 105775, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38458682

RESUMO

Insect cuticular protein (ICP) plays an important role in insect growth and development. However, research on the role of ICP in insecticide resistance is very limited. In this study, insect cuticular protein genes LCP17 and SgAbd5 were cloned and characterized in Helicoverpa armigera based on previous transcriptome data. The functions of LCP17 and SgAbd5 genes in fenvalerate resistance were assessed by RNA interference (RNAi), and their response to fenvalerate was further detected. The results showed that LCP17 and SgAbd5 were overexpressed in the fenvalerate-resistant strain comparing with a susceptible strain. The open reading frames of LCP17 and SgAbd5 genes were 423 bp and 369 bp, encoding 141 and 123 amino acids, respectively. LCP17 and SgAbd5 genes were highly expressed in the larval stage, but less expressed in the adult and pupal stages. The expression level of LCP17 and SgAbd5 genes increased significantly after fenvalerate treatment at 24 h. When the cotton bollworms larvae were exposed to fenvalerate at LD50 level, RNAi-mediated silencing of LCP17 and SgAbd5 genes increased the mortality from 50.68% to 68.67% and 63.89%, respectively; the mortality increased to even higher level, which was 73.61%, when these two genes were co-silenced. Moreover, silencing of these two genes caused the cuticle lamellar structure to become loose, which led to increased penetration of fenvalerate into the larvae. The results suggested that LCP17 and SgAbd5 may be involved in the resistance of cotton bollworm to fenvalerate, and LCP17 and SgAbd5 could serve as potential targets for H. armigera control.


Assuntos
Inseticidas , Mariposas , Nitrilas , Piretrinas , Animais , Inseticidas/toxicidade , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Mariposas/genética , Mariposas/metabolismo , Larva/genética , Larva/metabolismo
8.
Hum Exp Toxicol ; 43: 9603271241235408, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38472141

RESUMO

INTRODUCTION: Organophosphate pesticides (Ops) like diazinon (DZN) have well-known neurotoxic effects and low-level chronic exposure has been linked to detrimental neurobehavioral impairments and memory deficits. However, it's not entirely clear how DZN-induced biological changes, particularly in the prefrontal cortex (PFC) contribute to these effects. The purpose of this study is to investigate the impact of DZN exposure on inhibitory avoidance (IA) memory function, amyloid precursor expression (APP), and proinflammatory tumor necrosis factor-α (TNF-α) levels in the rat cortex. MATERIALS AND METHODS: Rats were divided into 4 groups and recived 2 mg/kg DZN for 5-days or 12-weeks and two control groups recived the same volume of vehicle. IA memory was assesed using the shuttle box apparatus. Rats were sacrificed and the prefrontal cortex PFC were removed. Real-time PCR and Western blotting were used to messure TNF-α, and amyloid protein precursors gene expression and protein levels. RESULTS: Our findings indicated that DZN caused body weight loss and a notable decline in performance on the IA memory. Additionally, 5-days exposure increased APP and APLP2 protein levels in the PFC, while 12-weeks exposure decreased these levels. Furthermore, expression of APP and APLP2 gens were decreased in PFC. TNF-α levels increased as a result of 5-days exposure to DZN, but these levels dropped to normal after 12-weeks administration, and this observation was significant. CONCLUSION: Taken together, exposure to low doses of DZN leads to disturbances in IA memory performance and also alternations in amyloid beta precursors that can be related to increased risk of Alzheimer's disease.


Assuntos
Diazinon , Inseticidas , Ratos , Animais , Diazinon/toxicidade , Fator de Necrose Tumoral alfa , Peptídeos beta-Amiloides , Estresse Oxidativo , Inseticidas/toxicidade , Córtex Pré-Frontal
9.
Proc Biol Sci ; 291(2019): 20232939, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38503336

RESUMO

Mounting evidence supporting the negative impacts of exposure to neonicotinoids on bees has prompted the registration of novel 'bee-friendly' insecticides for agricultural use. Flupyradifurone (FPF) is a butenolide insecticide that shares the same mode of action as neonicotinoids and has been assessed to be 'practically non-toxic to adult honeybees' using current risk assessment procedures. However, these assessments overlook some routes of exposure specific to wild bees, such as contact with residues in soil for ground-nesters. Co-exposure with other pesticides may also lead to detrimental synergistic effects. In a fully crossed experiment, we assessed the possible lethal and sublethal effects of chronic exposure to two pesticides used on Cucurbita crops, the insecticide Sivanto Prime (FPF) and the fungicide Quadris Top (azoxystrobin and difenoconazole), alone or combined, on solitary ground-nesting squash bees (Xenoglossa pruinosa). Squash bees exposed to Quadris Top collected less pollen per flower visit, while Sivanto-exposed bees produced larger offspring. Pesticide co-exposure induced hyperactivity in female squash bees relative to both the control and single pesticide exposure, and reduced the number of emerging offspring per nest compared to individual pesticide treatments. This study demonstrates that 'low-toxicity' pesticides can adversely affect squash bees under field-realistic exposure, alone or in combination.


Assuntos
4-Butirolactona/análogos & derivados , Inseticidas , Praguicidas , Piridinas , Pirimidinas , Estrobilurinas , Abelhas , Feminino , Animais , Praguicidas/toxicidade , Inseticidas/toxicidade , Neonicotinoides/toxicidade
10.
PLoS One ; 19(3): e0300899, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38527045

RESUMO

Pollution produced by exposure to pesticides is a major concern for food security because the negative impacts on pollinators. Fipronil, an insecticide broadly used around the globe has been associated with the ongoing decline of bees. With a characteristic neuroactive toxicodynamic, fipronil leads to cognitive and motor impairments at sublethal dosages. Despite of regional bans, multilevel strategies are necessary for the protection of pollinators. Recent evidence suggests that specific nutrients in the diets of bees may induce protection against insecticides. Here, we evaluated whether the administration of three phytochemicals, namely rutin, kaempferol and p-coumaric acid provide protection to the Africanized honey bee Apis mellifera against oral administration of realistic dosages of fipronil. We tested the potential impairment produced by fipronil and the protection induced by the phytochemicals in learning, 24h memory, sucrose sensitivity and motor control. We found that the administration of fipronil induced a concentration-dependent impairment in learning and motor control, but not 24h memory or sucrose sensitivity across a 24h window. We also found that the administration of rutin, p-coumaric acid, kaempferol and the mixture was innocuous and generally offered protection against the impairments induced by fipronil. Overall, our results indicate that bees can be prophylactically protected against insecticides via nutrition, providing an alternative to the ongoing conflict between the use of insecticides and the decline of pollinators. As the studied phytochemicals are broadly present in nectar and pollen, our results suggest that the nutritional composition, and not only its production, should be considered when implementing strategies of conservation via gardens and co-cropping.


Assuntos
Ácidos Cumáricos , Inseticidas , Transtornos Motores , Pirazóis , Abelhas , Animais , Inseticidas/toxicidade , Quempferóis , Sacarose , Compostos Fitoquímicos , Rutina , Administração Oral , Cognição
11.
Chemosphere ; 354: 141652, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38462182

RESUMO

The high diversity and distinctive characteristics of stingless bees pose challenges in utilizing toxicity test results for agrochemical registrations. Toxicity assessments were performed on 15 stingless bee species, along with the honey bee, using the insecticide dimethoate, following adapted OECD protocols. Median lethal doses over 24 h (24 h-LD50) were determined for exposure routes (acute oral or contact) and species. Species sensitivity distribution (SSD) curves were constructed and the 5% hazard doses (HD5) were estimated based on 24 h-LD50 values. The SSD curve was adjusted as the body weight and dimethoate response were correlated. Lighter bees (<10 mg) had lower 24 h-LD50 values. Contact exposure for adjusted HD5 suggested insufficient protection for Melipona mondury, whereas the oral exposure HD5 indicated no risks for the other 14 species. Comprehensive risk assessments are crucial for understanding the agrochemical impact on stingless bees, emphasizing the need for a broader species range in formulating conservation strategies.


Assuntos
Dimetoato , Inseticidas , Abelhas , Animais , Dimetoato/toxicidade , Inseticidas/toxicidade , Dose Letal Mediana , Agroquímicos , Peso Corporal
12.
Crit Rev Toxicol ; 54(3): 194-213, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38470098

RESUMO

Neonicotinoid pesticides are utilized against an extensive range of insects. A growing body of evidence supports that these neuro-active insecticides are classified as toxicants in invertebrates. However, there is limited published data regarding their toxicity in vertebrates and mammals. the current systematic review is focused on the up-to-date knowledge available for several neonicotinoid pesticides and their non-acute toxicity on rodents and human physiology. Oral lethal dose 50 (LD50) of seven neonicotinoids (i.e. imidacloprid, acetamiprid, clothianidin, dinotefuran, thiamethoxam, thiacloprid, and nitenpyram) was initially identified. Subsequently, a screening of the literature was conducted to collect information about non-acute exposure to these insecticides. 99 studies were included and assessed for their risk of bias and level of evidence according to the Office of Health and Translation (OHAT) framework. All the 99 included papers indicate evidence of reproductive toxicity, hepatotoxicity, nephrotoxicity, neurotoxicity, immunotoxicity, and oxidative stress induction with a high level of evidence in the health effect of rodents and a moderate level of evidence for human health. The most studied type of these insecticides among 99 papers was imidacloprid (55 papers), followed by acetamiprid (22 papers), clothianidin (21 papers), and thiacloprid (11 papers). While 10 of 99 papers assessed the relationship between clothianidin, thiamethoxam, dinotefuran, and nitenpyram, showing evidence of liver injury, dysfunctions of oxidative stress markers in the reproductive system, and intestinal toxicity. This systematic review provides a comprehensive overview of the potential risks caused by neonicotinoid insecticides to humans and rodents with salient health effects. However, further research is needed to better emphasize and understand the patho-physiological mechanisms of these insecticides, taking into account various factors that can influence their toxicity.


Assuntos
Guanidinas , Inseticidas , Tiazinas , Tiazóis , Animais , Humanos , Tiametoxam , Inseticidas/toxicidade , Oxazinas/toxicidade , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Medição de Risco , Mamíferos
13.
Sci Total Environ ; 925: 171698, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38499105

RESUMO

The exposure of organisms to microplastics could compromise their ability to cope with other environmental stressors, such as infections. In this context, we investigated the effects of a 14-day exposure of the terrestrial isopod Porcellio scaber to tire particles in soil (1.5 % w w-1 dry weight) on the organisms' response to a secondary exposure, i.e., injection of the bacterial endotoxin lipopolysaccharide. In addition, the insecticide chlorpyrifos (2 mg kg-1 dry weight) was tested as a positive control. The survival and immune response of P. scaber was assessed at the end of the 7- and 14-day primary exposure and two days after the secondary exposure, by analyzing selected haemolymph immune parameters (total haemocyte count, differential haemocyte count, and haemocyte viability). No change in survival was observed after primary exposure of P. scaber to tire particles or chlorpyrifos. However, primary exposure to chlorpyrifos triggered a strong activation of the immune response, which was not the case following exposure to the tire particles. Further injection of lipopolysaccharide into the body did not affect the survival of animals exposed to tire particles or chlorpyrifos, while a strong immunomodulatory change was observed, particularly with chlorpyrifos, and to some extent, tire particles. Based on these results, we conclude that exposure of P. scaber to tire particles or chlorpyrifos has no significant effect on the susceptibility of the organism to lipopolysaccharide in terms of their mortality, but primary exposure to an insecticide significantly modulates the immune response of the organisms to a second stressor. We discuss the "stress on stress" approach for testing low-toxic substances, such as microplastics, where an environmentally realistic exposure is followed by a secondary exposure.


Assuntos
Clorpirifos , Inseticidas , Isópodes , Animais , Inseticidas/toxicidade , Plásticos , Microplásticos , Lipopolissacarídeos/toxicidade , Clorpirifos/toxicidade
14.
J Toxicol Environ Health A ; 87(9): 381-397, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38466085

RESUMO

Tetrachlorvinphos (TCVP) is the pesticidal active ingredient found in some flea and tick collars for dogs and cats. Recent studies sponsored by The Hartz Mountain Corporation, confirm the safety of TCVP as an active ingredient in pet collars. Based upon data from these new studies and results previously relied upon by the U.S. Environmental Protection Agency, the following conclusions have been made: Torsion study data clearly indicate that approximately 93% of released formulation from TCVP containing pet collars is in a liquid phase immediately following activation.Further, even more relevant to human health risk analysis associated with post-application exposures, in vivo data from dogs wearing TCVP pet collars definitively document that TCVP dust released from the collar is rapidly absorbed into the sebum. The maximum ratio of dust to liquid was 0.023% dust to 99.977% liquid.In vivo fur data provide scientific evidence confirming that the mechanism of dissemination of TCVP from pet collars is as a liquid suspended or dissolved in the animal's sebum, even though it may be released from the collar as a solid. Thus, potential post-application exposure to TCVP, including immediately following collar placement, is almost entirely to a liquid phase.Based upon EPA's refined and conservative "untrimmed" collar risk assessment, post-application incidental oral hand-to-mouth activity by children aged 1 to <2 years of age results in margins of exposure significantly greater than the level of concern of 1000, and therefore do not present unreasonable health risk.


Assuntos
Doenças do Gato , Doenças do Cão , Inseticidas , Estados Unidos , Criança , Humanos , Animais , Gatos , Cães , Pré-Escolar , Tetraclorvinfos/análise , Inseticidas/toxicidade , Doenças do Gato/prevenção & controle , Medição de Risco , Poeira/análise
15.
Sci Rep ; 14(1): 6253, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491058

RESUMO

Sitotroga cerealella is a serious pest of a wide range of stored cereal grains. An essential element of an integrated pest control approach is the application of plant oils as a substitute for chemical insecticides. This study aimed to investigate the fumigant toxicity of Allium sativum and Mentha piperita essential oils against S. cerealella adult moths and the egg parasitoid Trichogramma evanescens. Gas chromatography-mass spectrometry analyses detected that Diallyl trisulfide (37.97%) and DL-Menthol (47.67%) as main compounds in A. sativum and M. piperita, respectively. The results showed that, A. sativum at 10.0, 5.0, and 2.5 µL/L air resulted in 100% insect mortality after 24 h exposure. The concentrations of 10.0 and 5.0 µL/L air of M. piperita oil resulted in 100 and 96% insect mortality, respectively. The parasitoid adult emergence in the F1 reduced when exposed to LC99 of A. sativum and M. piperita oils by 10.89 and 9.67%, respectively. Also, the parasitism of emerged parasitoid decreased by 9.25 and 5.84% (class I-harmless), respectively. Therefore A. sativum and M. piperita have the potential to be used as bio-fumigant for the management of S. cerealella and can be used alongside the T. evanescens in integrated pest management.


Assuntos
Himenópteros , Inseticidas , Mariposas , Óleos Voláteis , Praguicidas , Animais , Óleos Voláteis/toxicidade , Inseticidas/toxicidade
16.
Ecotoxicol Environ Saf ; 273: 116139, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38428240

RESUMO

The thyroid gland is susceptible to chemical exposure such as organophosphate insecticides (OPIs). With the ubiquitous nature of these products, humans are simultaneously exposed to a multitude of chemicals. This study aimed to evaluate the association between an individual and a mixture of OPI metabolites and changes in serum thyroid hormone (TH) concentrations. The analyzed data were 1,434 participants from the United States National Health and Nutrition Examination Surveys (NHANES) cycle 2007-2008. Generalized linear model (GLM) regression, weighted quantile sum (WQS), and adaptive least absolute shrinkage and selection operator (adaptive LASSO) regression were used to investigate the associations between urinary OPI metabolites and altered serum THs. In GLM, all of the five urinary OPI metabolites were inversely associated with free triiodothyronine (FT3) among the male subjects; meanwhile, higher thyroglobulin (Tg) was related to dimethylphosphate (DMP). Moreover, in WQS models, the metabolite mixture induced FT3 down-regulation (ß = -0.209 (95% CI: -0.310, -0.114)), and caused an increased Tg concentration (ß = 0.120 (95% CI: 0.024, 0.212)), however, any significant association was observed among female participants. Consistently, the weighted index and LASSO coefficient demonstrated dimethylthiophosphate (DMTP) as the strongest metabolite in the FT3 model (mean weight= 3.449e-01 and ß =-0.022, respectively), and dimethylphosphate (DMP) represented the highest association in the Tg model (mean weight= 9.873e-01 and ß =-0.020, respectively). Further research is required to confirm our results and investigate the clinical impacts of these disruptions.


Assuntos
Inseticidas , Compostos Organofosforados , Adulto , Humanos , Masculino , Feminino , Estados Unidos , Inseticidas/toxicidade , Inquéritos Nutricionais , Hormônios Tireóideos , Organofosfatos/toxicidade , Organofosfatos/urina
17.
J Hazard Mater ; 469: 133915, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38452669

RESUMO

Neonicotinoids are widely used insecticides that have raised considerable concerns for both environmental and human health. However, there lack of comprehensive evaluation of their accumulation in surface water ecosystems and exposure to various human groups. Additionally, there's a distinct lack of scientific evidence describing the carcinogenic and non-carcinogenic impacts of neonicotinoids from surface water. Using an integrated approach employing the Relative Potency Factor (RPF), Hazard Index (HI), and Monte Carlo Simulation (MCS), the study assessed neonicotinoid exposure and risk to four demographic groups via dermal contact and mistaken oral intake pathways in the Yangtze River Basin (YRB), China. Neonicotinoid concentrations range from 0.1 to 408.12 ng/L, indicating potential risk (10-3 to 10-1) across the studied demographic groups. The Incremental Lifetime Cancer Risk (ILCR) for dermal contact was within a moderate range of 2.00 × 10-3 to 1.67 × 10-2, while the mistaken oral intake was also within a moderate range of 3.07 × 10-3 to 7.05 × 10-3. The Hazard Index (HI) for dermal exposure ranged from 1.49 × 10-2 to 0.125, while for mistaken oral intake, it varied between 2.69 × 10-2 and 0.14. The findings highlight the importance of implementing specific interventions to address neonicotinoid exposure, especially among demographic groups that are more susceptible. This research underscores the urgent need for targeted strategies to address neonicotinoid risks to vulnerable populations within the YRB while contributing to insights for effective policies to mitigate neonicotinoid exposure in surface water ecosystems globally.


Assuntos
Inseticidas , Poluentes Químicos da Água , Humanos , Inseticidas/toxicidade , Inseticidas/análise , Água , Rios , Ecossistema , Neonicotinoides/toxicidade , China , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise
18.
Ecotoxicology ; 33(2): 226-234, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38424316

RESUMO

The use of insecticides in agricultural settings often exerts negative effects on nontarget species. Methomyl, a broad-spectrum carbamate insecticide, is recommended to manage a number of insect pests of the cotton crop. Recently, Musca domestica, which is a nontarget insect species in cotton fields, has shown resistance to methomyl in Pakistan. The present study tried to assess resistance-risk assessment, rapidity of resistance development to methomyl, cross-resistance potential to other insecticides, resistance heritability and to forecast the projected rate of resistance development under field conditions. For this purpose, a field strain of M. domestica with 186 fold resistance to methomyl was re-selected in the laboratory for eight consecutive generations. Consequently, LD50 values increased rapidly (126.64 ng/fly to 3112.79 ng/fly) compared to those before selection experiments. Similarly, RR values increased from 186 to 3113 fold as a result of the selection process. However, resistance to methomyl did not remain stable when the selected strain (Meth-SEL) reared for the next five generations in a pesticide free environment. The Meth-SEL strain also developed cross-resistance to permethrin. The realized heritability (h2) value for the Meth-SEL strain was 0.39 with 27% average mortality of M. domestica. Assuming the standard deviation (σp) value 0.27 and the h2 value 0.39 for eight generations of continuous exposure to methomyl, then five, seven, eight, ten and twelve generations at 90, 80, 70, 60 and 50% selection intensity, respectively, would be required for a tenfold increase in the LD50 value of methomyl. In conclusion, the Meth-SEL strain of M. domestica exhibited a high risk of resistance development to methomyl under continuous selection pressure. Resistance increased rapidly during selection experiments that reflect the probability of resistance development under field conditions if M. domestica receive exposures to methomyl during its applications for the management of target pest species.


Assuntos
Moscas Domésticas , Inseticidas , Animais , Moscas Domésticas/genética , Inseticidas/toxicidade , Metomil , Permetrina , Medição de Risco , Resistência a Inseticidas/genética
19.
Sci Total Environ ; 919: 170937, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38360305

RESUMO

Neonicotinoids are broad-spectrum and highly effective insecticides that work by affecting neural activity in insects. Neonicotinoids are systemic pesticides that are absorbed by plants, transported, and accumulated in plant tissues, including nectar and pollen. Currently, there is a lack of a comprehensive assessment of the level of neonicotinoid contamination and the associated health risks to non-targeted organisms in commercial honey and pollen produced in China. This study collected 160 batches of honey and 26 batches of pollen from different regions and plant sources in China, analyzed the residue patterns of neonicotinoid pesticides, and comprehensively evaluated the exposure risks to non-targeted organisms including bees (adults and larvae) and humans. Furthermore, this study addresses this imperative by establishing a high-throughput, rapid, and ultra-sensitive indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) based on broad-spectrum monoclonal antibodies to detect and quantify neonicotinoids, with validation conducted using the LC-MS/MS method. The findings indicated that 59.4 % of honey samples contained at least one of eight neonicotinoids, and the ic-ELISA rapid detection and calculation method could detect all the samples containing neonicotinoids. Additionally, the dietary risk assessment for humans and honeybees indicates that the consumption of a specific quantity of honey may not pose a health risk to human due to neonicotinoid intake. However, the Risk Quotient values for imidacloprid to adult bees and bee larvae, as well as clothianidin to bee larvae, were determined to be 2.22, 5.03, and 1.01, respectively-each exceeding 1. This highlights the elevated risk of acute toxicity posed by imidacloprid and clothianidin residues to honey bees. The study bears significant implications for the safety evaluation of non-targeted organisms in the natural food chain. Moreover, it provides scientific guidance for protecting the diversity and health of the ecosystem.


Assuntos
Ecossistema , Guanidinas , Inseticidas , Tiazóis , Humanos , Abelhas , Animais , Cromatografia Líquida , Espectrometria de Massas em Tandem , Neonicotinoides/toxicidade , Neonicotinoides/análise , Nitrocompostos/análise , Inseticidas/toxicidade , Inseticidas/análise , Pólen/química , Plantas , Medição de Risco
20.
Ecotoxicol Environ Saf ; 272: 116040, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38306817

RESUMO

Insecticides are an indispensable and important tool for agricultural production. However, the inappropriate application of insecticides can cause damage to the food chain and ecosystem. Orius similis is an important predatory and natural enemy of Frankliniella occidentalis. Imidacloprid is widely used to control pests, but will inevitably exert adverse effects on O. similis. In order to determine the effect of different imidacloprid treatments on the ability of O. similis to prey on the 2nd-instar nymphs of F. occidentalis, we determined the toxicity and predation of imidacloprid on different stages of O. similis under contact and ingestion treatments. In addition, we used the Holling disc equation to evaluate the ability of O. similis to search and exhibit predatory activity following contact and ingestion treatments. Analysis showed that the highest LC10 and LC20 values for imidacloprid contact and ingestion toxicity treatment were 17.06 mg/L and 23.74 mg/L, respectively. Both imidacloprid treatments led toa reduction in the predatory of O. similis on prey. The functional responses of the 3rd to 5th instar nymphs, along with female and male O. similis adults to the 2nd-instar nymphs of F. occidentalis were consistent with the Holling type II response following contact and ingestion with imidacloprid. However, following imidacloprid treatment, the handing time (Th) of O. similis with single F. occidentalis was prolonged and the instantaneous attack rate (a) was reduced after imidacloprid treatment. The predatory capacity (a/Th) of female O. similis adults when treated with the LC10 concentration of imidacloprid by ingestion was 52.85; this was lower than that of the LC10 concentration of imidacloprid in the contact treatment (57.67). The extent of predation of O. similis on the 2nd-instar nymphs of F. occidentalis was positively correlated with prey density, although the search effect was negatively correlated with prey density. The most extensive search effect was exhibited by adult O. similis females. Simulations with the Hessell-Varley interference model showed that an increase in the number of O. similis would reduce search efficiency regardless of whether they were treated with imidacloprid or not. Thus, O. similis, especially female adults, exhibited strong potential for controlling the 2nd-instar nymphs of F. occidentalis. The toxicity of ingestion following treatment with the same concentration of imidacloprid in O. similis was greater than that of contact treatment. When using O. similis to control F. occidentalis in the field, we should increase the number of female adults released, and prolong the interval between imidacloprid treatment and O. similis exposure. This strategy will improve the control ability of O. similis, coordinate both chemical and biological control, reduce the impact of pesticides on the environment, and improve the efficiency of agricultural production.


Assuntos
Inseticidas , Neonicotinoides , Nitrocompostos , Animais , Feminino , Masculino , Inseticidas/toxicidade , Cadeia Alimentar , Comportamento Predatório , Ecossistema , Comportamento Alimentar , Ninfa
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