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1.
Braz. j. biol ; 83: e250373, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339376

RESUMO

Abstract Honey is a suitable matrix for the evaluation of environmental contaminants including organochlorine insecticides. The present study was conducted to evaluate residues of fifteen organochlorine insecticides in honey samples of unifloral and multifloral origins from Dir, Pakistan. Honey samples (5 g each) were extracted with GC grade organic solvents and then subjected to Rotary Evaporator till dryness. The extracts were then mixed with n-Hexane (5 ml) and purified through Column Chromatography. Purified extracts (1μl each) were processed through Gas Chromatograph coupled with Electron Capture Detector (GC-ECD) for identification and quantification of the insecticides. Of the 15 insecticides tested, 46.7% were detected while 53.3% were not detected in the honey samples. Heptachlor was the most prevalent insecticide with a mean level of 0.0018 mg/kg detected in 80% of the samples followed by β-HCH with a mean level of 0.0016 mg/kg detected in 71.4% of the honey samples. Honey samples from Acacia modesta Wall. were 100% positive for Heptachlor with a mean level of 0.0048 mg/kg followed by β-HCH with a mean level of 0.003 mg/kg and frequency of 83.3%. Minimum levels of the tested insecticides were detected in the unifloral honey from Ziziphus jujuba Mill. Methoxychlor, Endosulfan, Endrin and metabolites of DDT were not detected in the studied honey samples. Some of the tested insecticides are banned in Pakistan but are still detected in honey samples indicating their use in the study area. The detected levels of all insecticides were below the Maximum Residue Levels (MRLs) and safe for consumers. However, the levels detected can cause mortality in insect fauna. The use of banned insecticides is one of the main factors responsible for the declining populations of important insect pollinators including honeybees.


Resumo O mel é uma matriz adequada para a avaliação de contaminantes ambientais, incluindo inseticidas organoclorados. O presente estudo foi conduzido para avaliar resíduos de 15 inseticidas organoclorados em amostras de mel de origem unifloral e multifloral de Dir, Paquistão. Amostras de mel (5 g cada) foram extraídas com solventes orgânicos de grau GC e, em seguida, submetidas ao evaporador rotativo até a secura. Os extratos foram então misturados com n-hexano (5 ml) e purificados por cromatografia em coluna. Os extratos purificados (1μl cada) foram processados através de cromatógrafo gasoso acoplado a detector de captura de elétrons (GC-ECD) para identificação e quantificação dos inseticidas. Dos 15 inseticidas testados, 46,7% foram detectados enquanto 53,3% não foram detectados nas amostras de mel. O heptacloro foi o inseticida mais prevalente com um nível médio de 0,0018 mg / kg detectado em 80% das amostras, seguido por β-HCH com um nível médio de 0,0016 mg / kg detectado em 71,4% das amostras de mel. Amostras de mel da parede de Acacia modesta foram 100% positivos para heptacloro com um nível médio de 0,0048 mg / kg seguido por β-HCH com um nível médio de 0,003 mg / kg e frequência de 83,3%. Níveis mínimos dos inseticidas testados foram detectados no mel unifloral de Ziziphus jujuba da usina. Metoxicloro, Endosulfan, Endrin e metabólitos do DDT não foram detectados nas amostras de mel estudadas. Alguns dos inseticidas testados são proibidos no Paquistão, mas ainda são detectados em amostras de mel, indicando seu uso na área de estudo. Os níveis detectados de todos os inseticidas estavam abaixo dos Níveis Máximos de Resíduos (MRLs) e seguros para os consumidores. No entanto, os níveis detectados podem causar mortalidade na fauna de insetos. O uso de inseticidas proibidos é um dos principais fatores responsáveis pelo declínio das populações de importantes insetos polinizadores, incluindo as abelhas.


Assuntos
Animais , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/toxicidade , Mel/análise , Inseticidas/toxicidade , Abelhas , Biomarcadores Ambientais , Endossulfano/análise
2.
Braz. j. biol ; 83: e240118, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278559

RESUMO

Abstract For many centuries human populations have been suffering and trying to fight with disease-bearing mosquitoes. Emerging and reemerging diseases such as Dengue, Zika, and Chikungunya affect billions of people around the world and recently has been appealing to control with chemical pesticides. Malathion (MT) is one of the main pesticides used against mosquitoes, the vectors of these diseases. This study aimed to assess cytotoxicity and mutagenicity of the malathion for the bioindicator Allium cepa L. using a multivariate and integrative approach. Moreover, an appendix table was compiled with all available literature of insecticides assessed by the Allium cepa system to support our discussion. Exposures during 48h to 0.5 mg mL-1 and 1.0 mg mL-1 MT were compared to the negative control (distilled water) and positive control (MMS solution at 10 mg L-1). The presence of chromosomal aberrations, micronuclei frequency, and mitotic index abnormalities was evaluated. Anaphase bridges were the alterations with higher incidence and presented a significantly elevated rate in the concentration of 0.5 mg mL-1, including when compared to the positive control. The integrative discriminant analysis summarizes that MT in assessed concentrations presented effects like the positive control, corroborating its potential of toxicity to DNA. Therefore, it is concluded that MT in its pure composition and in realistic concentrations used, has genotoxic potential in the biological assessment of A. cepa cells. The multivariate integrative analysis was fundamental to show a whole response of all data, providing a global view of the effect of MT on DNA.


Resumo Por muitos séculos, as populações humanas sofrem e tentam combater os mosquitos transmissores de doenças. Doenças emergentes e reemergentes como Dengue, Zika e Chikungunya afetam bilhões de pessoas em todo o mundo e, recentemente, vem apelando ao controle com pesticidas químicos. O Malation (MT) é um dos principais pesticidas usados ​​contra mosquitos, vetores dessas doenças. O objetivo deste estudo foi avaliar a citotoxicidade e a mutagenicidade do MT para o bioindicador Allium cepa L. usando uma abordagem multivariada e integrativa. Além disso, uma tabela suplementar foi compilada com toda a literatura disponível de inseticidas avaliada pelo sistema Allium cepa para apoiar nossa discussão. Exposições ao MT durante 48h a 0,5 mg mL-1 e 1,0 mg mL-1 foram comparadas a um controle negativo (água destilada) e um controle positivo (10 mg L-1 de MMS). Foram avaliadas a presença de aberrações cromossômicas, frequência de micronúcleos e anormalidades no índice mitótico. As pontes anafásicas foram as alterações com maior incidência e apresentaram uma taxa significativamente elevada na concentração de 0,5 mg mL-1, inclusive quando comparadas ao controle positivo. A análise discriminante integrativa resume que o MT nas concentrações avaliadas apresentou efeitos semelhantes ao controle positivo, corroborando seu potencial de toxicidade para o DNA. Portanto, conclui-se que o MT, em sua composição pura e nas concentrações realistas utilizadas, possui potencial genotóxico na avaliação biológica de células de A. cepa. A análise integrativa multivariada foi fundamental para mostrar uma resposta completa de todos os dados, fornecendo uma visão global do efeito da MT no DNA.


Assuntos
Humanos , Animais , Zika virus , Infecção por Zika virus , Inseticidas/toxicidade , Dano ao DNA , Aberrações Cromossômicas , Raízes de Plantas , Cebolas , Mosquitos Vetores , Malation/toxicidade , Índice Mitótico
3.
Braz. j. biol ; 83: e244647, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278527

RESUMO

Abstract The essential oil of citronella (Cymbopogon winterianus) has several biological activities, among them the insect repellent action. Some studies showed that cinnamic acid esters can be applied as natural pesticides, insecticides and fungicides. In this context, the objective of the present work was to evaluate the production of esters from citronella essential oil with cinnamic acid via enzymatic esterification. Besides, the essential oil toxicity before and after esterification against Artemia salina and larvicidal action on Aedes aegypti was investigated. Esters were produced using cinnamic acid as the acylating agent and citronella essential oil (3:1) in heptane and 15 wt% NS 88011 enzyme as biocatalysts, at 70 °C and 150 rpm. Conversion rates of citronellyl and geranyl cinnamates were 58.7 and 69.0% for NS 88011, respectively. For the toxicity to Artemia salina LC50 results of 5.29 μg mL-1 were obtained for the essential oil and 4.36 μg mL-1 for the esterified oils obtained with NS 88011. In the insecticidal activity against Aedes aegypti larvae, was obtained LC50 of 111.84 μg mL-1 for the essential oil of citronella and 86.30 μg mL-1 for the esterified oils obtained with the enzyme NS 88011, indicating high toxicity of the esters. The results demonstrated that the evaluated samples present potential of application as bioinsecticide.


Resumo O óleo essencial de citronela (Cymbopogon winterianus) possui diversas atividades biológicas, entre elas a ação repelente a insetos. Alguns estudos mostraram que os ésteres do ácido cinâmico podem ser aplicados como pesticidas naturais, inseticidas e fungicidas. Nesse contexto, o objetivo do presente trabalho foi avaliar a produção de ésteres a partir do óleo essencial de citronela com ácido cinâmico via esterificação enzimática. Além disso, foi investigada a toxicidade do óleo essencial antes e após a esterificação contra Artemia salina e a ação larvicida sobre Aedes aegypti. Os ésteres foram produzidos utilizando ácido cinâmico como agente acilante e óleo essencial de citronela (3: 1) em heptano e 15% em peso da enzima NS 88011 como biocatalisadores, a 70 ° C e 150 rpm. As taxas de conversão de cinamatos de citronelil e geranil foram 58,7 e 69,0% para NS 88011, respectivamente. Para a toxicidade sobre Artemia salina foram obtidos CL50 de 5,29 μg mL-1 para o óleo essencial e 4,36 μg mL-1 para os óleos esterificados com NS 88011. Na atividade inseticida contra larvas de Aedes aegypti, obteve-se CL50 de 111,84 μg mL-1 para o óleo essencial de citronela e 86,30 μg mL-1 para os óleos esterificados com a enzima NS 88011, indicando alta toxicidade dos ésteres. Os resultados demonstraram que as amostras avaliadas apresentam potencial de aplicação como bioinseticida.


Assuntos
Animais , Óleos Voláteis/toxicidade , Aedes , Cymbopogon , Repelentes de Insetos , Inseticidas/toxicidade , Esterificação , Larva
4.
Environ Health ; 21(1): 74, 2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35934697

RESUMO

BACKGROUND: Organophosphate (OP) insecticides represent one of the largest classes of sprayed insecticides in the U.S., and their use has been associated with various adverse health outcomes, including disorders of blood pressure regulation such as hypertension (HTN). METHODS: In a study of 935 adults from the NHANES 2013-2014 cycle, we examined the relationship between systolic and diastolic blood pressure changes and urinary concentrations of three OP insecticides metabolites, including 3,5,6-trichloro-2-pyridinol (TCPy), oxypyrimidine, and para-nitrophenol. These metabolites correspond to the parent compounds chlorpyrifos, diazinon, and methyl parathion, respectively. Weighted, multivariable linear regression analysis while adjusting for potential confounders were used to model the relationship between OP metabolites and blood pressure. Weighted, multivariable logistic regression analysis was used to model the odds of HTN for quartile of metabolites. RESULTS: We observed significant, inverse association between TCPy on systolic blood pressure (ß-estimate = -0.16, p < 0.001) and diastolic blood pressure (ß-estimate = -0.15, p < 0.001). Analysis with para-nitrophenol revealed a significant, positive association with systolic blood pressure (ß-estimate = 0.03, p = 0.02), and an inverse association with diastolic blood pressure (ß-estimate = -0.09, p < 0.001). For oxypyrimidine, we observed significant, positive associations between systolic blood pressure (ß-estimate = 0.58, p = 0.03) and diastolic blood pressure (ß-estimate = 0.31, p < 0.001). Furthermore, we observed significant interactions between TCPy and ethnicity on systolic blood pressure (ß-estimate = 1.46, p = 0.0036). Significant interaction terms were observed between oxypyrimidine and ethnicity (ß-estimate = -1.73, p < 0.001), as well as oxypyrimidine and BMI (ß-estimate = 1.51 p < 0.001) on systolic blood pressure, and between oxypyrimidine and age (ß-estimate = 1.96, p = 0.02), race (ß-estimate = -3.81 p = 0.004), and BMI on diastolic blood pressure (ß-estimate = 0.72, p = 0.02). A significant interaction was observed between para-nitrophenol and BMI for systolic blood pressure (ß-estimate = 0.43, p = 0.01), and between para-nitrophenol and ethnicity on diastolic blood pressure (ß-estimate = 2.19, p = 0.006). Lastly, we observed a significant association between the odds of HTN and TCPy quartiles (OR = 0.65, 95% CI [0.43,0.99]). CONCLUSION: Our findings support previous studies suggesting a role for organophosphate insecticides in the etiology of blood pressure dysregulation and HTN. Future studies are warranted to corroborate these findings, evaluate dose-response relationships between organophosphate insecticides and blood pressure, determine clinical significance, and elucidate biological mechanisms underlying this association.


Assuntos
Clorpirifos , Hipertensão , Inseticidas , Adulto , Pressão Sanguínea , Humanos , Hipertensão/induzido quimicamente , Hipertensão/epidemiologia , Inseticidas/toxicidade , Inseticidas/urina , Nitrofenóis , Inquéritos Nutricionais , Compostos Organofosforados/urina
5.
PLoS One ; 17(8): e0272514, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35921304

RESUMO

Sulfoxaflor is a new insecticide which acts on the nicotinic acetylcholine receptor (nAChRs) in a similar way to neonicotinoids. However, sufloxaflor (SFX) is thought to act in a different manner and is thus proposed as an alternative in crop protection. The goal of this study is to evaluate the toxicity of SFX and its sublethal effect on the honeybee Apis mellifera after acute exposure. In toxicological assay studies, the LD50 value and sublethal dose (corresponding to the NOEL: no observed effect level) were 96 and 15 ng/bee, respectively. Using the proboscis extension response paradigm, we found that an SFX dose of 15 ng/bee significantly impairs learning and memory retrieval when applied 12 h before conditioning or 24 h after olfactory conditioning. SFX had no effect on honeybee olfactory performance when exposure happened after the conditioning. Relative quantitative PCR experiments performed on the six nicotinic acetylcholine receptor subunits demonstrated that they are differently expressed in the honeybee brain after SFX exposure, whether before or after conditioning. We found that intoxicated bees with learning defects showed a strong expression of the Amelß1 subunit. They displayed overexpression of Amelα9 and Amelß2, and down-regulation of Amelα1, Amelα3 and Amelα7 subunits. These results demonstrated for the first time that a sublethal dose of SFX could affect honeybee learning and memory performance and modulate the expression of specific nAChR subunits in the brain.


Assuntos
Inseticidas , Receptores Nicotínicos , Animais , Abelhas/genética , Inseticidas/toxicidade , Aprendizagem , Neonicotinoides/toxicidade , Piridinas , Receptores Nicotínicos/genética , Receptores Nicotínicos/metabolismo , Compostos de Enxofre/farmacologia
6.
Sci Rep ; 12(1): 11926, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35831394

RESUMO

Imidacloprid is a neonicotinoid insecticide used to control agricultural pests around the world. This pesticide can have adverse effects on non-target organisms, especially in aquatic environments. The present study evaluated the toxicity of an imidacloprid-based insecticide in amphibians, using Leptodactylus luctator and Physalaemus cuvieri tadpoles as study models. Spawning of both species were collected within less than 24 h of oviposition from a non-agricultural land at Erechim, Rio Grande do Sul state, Brazil. Survival, swimming activity, body size, morphological malformations, and genotoxic parameters were analyzed at laboratory conditions. A short-term assay was conducted over 168 h (7 days) with five different concentrations of imidacloprid (3-300 µg L-1) being tested. The insecticide did not affect survival, although the tadpoles of both species presented reduced body size, malformed oral and intestine structures, and micronuclei and other erythrocyte nuclear abnormalities following exposure to this imidacloprid-based compound. Exposure also affected swimming activity in L. luctator, which reflected the greater sensitivity of L. luctator to imidacloprid in comparison with P. cuvieri. The swimming activity, body size, and malformations observed in L. luctator and the morphological malformations found in P. cuvieri indicated that even the lowest tested concentration of the insecticide were harmful to amphibians. At concentrations of over 3 µg L-1, P. cuvieri presents a smaller body size, and both species are affected by genotoxic cell damage. This demonstrates that imidacloprid is potentially toxic for the two study species at environmentally relevant concentrations.


Assuntos
Inseticidas , Poluentes Químicos da Água , Animais , Anuros , Dano ao DNA , Inseticidas/toxicidade , Larva , Neonicotinoides/toxicidade , Nitrocompostos , Poluentes Químicos da Água/toxicidade
7.
Artigo em Inglês | MEDLINE | ID: mdl-35805859

RESUMO

This is a preliminary study conducted to analyze the presence and concentration of pesticides in honey obtained from honey bee colonies located in two regions with managed ecosystems that differ in the intensity and technification of agricultural practices. Fourteen pesticides at variable concentrations were detected in 63% of the samples analyzed. The pesticides most frequently found at higher concentrations were insecticides (neonicotinoids, followed by organophosphates), herbicides, and fungicides. The number, frequency, and concentration of pesticides were higher in samples collected from hives located where intensive and highly-technified agriculture is practiced. Forty-three percent of the samples from that zone had residues of imidacloprid, compared with only 13% of the samples from the less-technified zone. Furthermore, 87.5% of those samples had imidacloprid concentrations that were above sublethal doses for honey bees (>0.25 ng/g) but that are not considered hazardous to human health by the European Commission. The results of this study suggest that honey can be used as a bioindicator of environmental contamination by pesticides, which highlights the need to continue monitoring contaminants in this product to determine the risks of pesticide impacts on pollinator health, on ecosystems, and on their potential implications to human health and other non-target organisms.


Assuntos
Inseticidas , Praguicidas , Agricultura , Animais , Abelhas , Ecossistema , Humanos , Inseticidas/análise , Inseticidas/toxicidade , Neonicotinoides
8.
Ecotoxicology ; 31(6): 998-1008, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35779162

RESUMO

Pyriproxyfen is a juvenile hormone analogue that is commonly used to control the immature stages of mosquitoes in both artificial and natural water reservoirs. Recently, concerns have been raised regarding the community effectiveness of pyriproxyfen in preventing vector-transmitted diseases. Such concerns have been based on the unintended effects on non-target organisms and the selection of resistant mosquito populations. This investigation was, therefore, conducted to evaluate the toxicity of pyriproxyfen to Aedes aegypti (Diptera: Culicidae) larvae and the backswimmer Buenoa amnigenus (Hemiptera: Notonectidae), a naturally occurring mosquito larvae predator. We also assessed the abilities of backswimmers exposed to sublethal levels of pyriproxyfen to prey upon mosquito larvae (L2) under three larval densities (3, 6, or 9 larvae/100 mL of water) using artificial containers. Our results revealed that pyriproxyfen killed backswimmers only at concentrations higher than 100 µg active ingredient [a.i.]/L, which is 10 times higher than that recommended for larvicidal field application (i.e, 10 µg a.i./L). The abilities of backswimmers exposed to sublethal levels of pyriproxyfen (100 µg a.i./L) to prey upon mosquito larvae were not affected. Harmful effects on the backswimmer predatory abilities were detected only at concentrations of 150 µg a.i./L and when there was a higher prey availability (i.e., 9 larvae/100 mL of water). Together, our findings indicate that the reduced community effectiveness of this insecticide derives from factors other than its detrimental effects on non-target organisms such as backswimmers.


Assuntos
Aedes , Heterópteros , Inseticidas , Animais , Inseticidas/toxicidade , Larva , Controle de Mosquitos/métodos , Mosquitos Vetores , Piridinas , Água
9.
BMC Pharmacol Toxicol ; 23(1): 46, 2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35804463

RESUMO

BACKGROUND: Permethrin is one of the pyrethroid insecticides, which is widely used in agriculture and public health. Although acute toxicity of the insecticide has been studied, the chronic toxicity upon the long-term exposure has not been clear yet. The purpose of the current study is to investigate the organ toxicities of permethrin following its long-term low-dose exposure. METHODS: Male Wistar rats were daily administrated orally with permethrin (75 mg/kg body weight/day, gavage) for 90 days, and then the samples of biofluids (blood and urine) and organs including liver and kidney were collected. The serum and urine samples were measured by biochemical assay and the tissues of kidney and liver were examined and analyzed by histopathological method. RESULTS: The results showed that no change was found in serum and urine biochemical parameters for the toxicity; however, significant changes including hyperchromatic nuclei swollen in the hepatic parenchymal cells and the swelling proximal tubules in the kidneys were observed in the tissue structures of liver and kidneys in the histopathological sections. CONCLUSION: These results indicate that low-dose long-term exposure of permethrin can cause chronic toxicity with slight liver and kidney damage.


Assuntos
Inseticidas , Permetrina , Animais , Inseticidas/toxicidade , Rim/patologia , Fígado/patologia , Masculino , Permetrina/toxicidade , Ratos , Ratos Wistar
10.
Biosci Rep ; 42(7)2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35822445

RESUMO

The present study aimed to develop a novel methodology for controlling the mosquito larvae using different nanoparticles, with special reference to their effect on rats (a non-target mammalian model). The mosquito species of Culex quinquefasciatus was reared in the laboratory. Chitosan, silver nanoparticles and their combination as well as lavender (Lavandula officinalis) nanoemulsion with different concentrations were tested as biological insecticides against the mosquito larvae. Mammalian toxicity of the used nanoparticles were evaluated using 27 adult male rats, experimental rats were divided into 9 equal groups (n=3). The nanoparticles were added to the drinking water for 30 days. At the end of the study, blood and tissue samples were collected to assess the levels of the serum alanine aminotransferase and aspartate aminotransferase, different genes expression as interleukin 6 (IL-6) and IL-1ß activity. Histopathological and immunohistochemical studies using two markers (TNF-α and BAX expression) were also applied. The LC50 and LC90 were recorded for each tested nanoparticles, and also the changes of the treated mosquito larvae cuticle were assessed using the scanning electron microscopy. Green nanoemulsion (Lavandula officinalis) was more effective than metal (silver) or even biodegradable (chitosan) nanoparticles in controlling of Culex quiquefasciatus mosquito larvae, and also it proved its safety by evaluation of the mammalian hepatotoxicity of the tested nanoparticles.


Assuntos
Aedes , Anopheles , Doença Hepática Induzida por Substâncias e Drogas , Quitosana , Culex , Inseticidas , Nanopartículas Metálicas , Animais , Anopheles/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Culex/metabolismo , Inseticidas/toxicidade , Larva/metabolismo , Masculino , Mamíferos/metabolismo , Nanopartículas Metálicas/toxicidade , Extratos Vegetais/farmacologia , Folhas de Planta/metabolismo , Ratos , Prata/toxicidade
11.
Molecules ; 27(15)2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35897869

RESUMO

In order to discover pesticidal lead compounds with high activity and low toxicity, a series of novel benzamides substituted with pyrazole-linked 1,2,4-oxadiazole were designed via bioisosterism. The chemical structures of the target compounds were confirmed via 1H NMR, 13C NMR and HRMS analysis. The preliminary bioassay showed that most compounds exhibited good lethal activities against Mythimna separate, Helicoverpa armigera, Ostrinia nubilalis and Spodoptera frugiperda at 500 mg/L. Particularly in the case of Mythimna separate, compound 14q (70%) exhibited obvious insecticidal activity. In addition, compound 14h demonstrated good fungicidal activity against Pyricularia oryae with an inhibition rate of 77.8%, and compounds 14e, 14k, 14n and 14r also showed certain antifungal activities (55.6-66.7%). The zebrafish toxicity test showed that the LC50 of compound 14h was 14.01 mg/L, which indicated that it may be used as a potential leading compound for further structural optimization.


Assuntos
Inseticidas , Mariposas , Animais , Benzamidas , Desenho de Fármacos , Inseticidas/toxicidade , Estrutura Molecular , Oxidiazóis/química , Oxidiazóis/toxicidade , Pirazóis/toxicidade , Relação Estrutura-Atividade , Peixe-Zebra
12.
PLoS One ; 17(7): e0271417, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35862486

RESUMO

Although insecticide formulations and spray rates are optimized to achieve lethal exposure, there are many factors in agricultural settings that can reduce the effective exposure of insect pests. These include weather patterns, timing of application, chemical degradation/volatilization, plant structural complexity, and resistant populations. While sub-lethal exposure to insecticides can still have negative impacts on pest populations, they can also lead to stimulatory, or hormetic, responses that can increase the fitness of surviving insects. Sub-lethal concentrations may also produce increased tolerance in the offspring of surviving adults through transgenerational effects. Sub-lethal effects are pertinent for the invasive fruit pest, spotted-wing Drosophila, Drosophila suzukii (Matsumura), because its small size, diurnal movement patterns, and utilization of hosts with complex plant structures, such as caneberries and blueberries, make effective insecticide applications tenuous. In this study, we measured spotted-wing Drosophila survivorship, reproductive performance, and offspring tolerance in flies exposed to sub-lethal concentrations of three commonly-used insecticides (zeta-cypermethrin, spinetoram, and pyrethrin). We found some evidence for hormesis, with survival effects being sex- and concentration-dependent for all insecticides. Males were far more susceptible to insecticides than females, which in some cases exhibited higher eclosion success and reproductive rates when exposed to sub-lethal doses. We did not observe significant transgenerational effects at sub-lethal concentrations, despite trends of increased offspring viability for zeta-cypermethrin and spinetoram. More research, however, is needed to fully understand the role that sub-lethal effects may play in pest population dynamics, insecticide efficacy, and the development of genetic resistance.


Assuntos
Mirtilos Azuis (Planta) , Himenópteros , Inseticidas , Animais , Drosophila , Feminino , Hormese , Controle de Insetos , Inseticidas/toxicidade , Masculino
13.
Toxicol In Vitro ; 83: 105426, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35781001

RESUMO

As commonly used neonicotinoid insecticides for pest control, imidacloprid (IMI) and acetamiprid (ACE) posed neurotoxicity effects on living organisms. However, researches of the differences in toxicity mechanism between these two neonicotinoid insecticides are still limited. In this study, different cellular metabolism perturbations and redox homeostasis damages induced by IMI and ACE exposure in Neuro-2a cells were investigated. Distinct elevation of lactate dehydrogenase (LDH) activity and caspase 7 level demonstrated the influences on necrosis and apoptosis. There were 21 and 12 metabolites screened out as potential biomarkers after IMI and ACE exposure, including lipids and amino acids. Remarkable decrease of lipid hydroperoxides (LOOH) and increase of reactive oxygen species (ROS) generation were found only in the ACE20 group. Interference with glutathione metabolism pathway was further validated by detecting GPx (glutathion peroxidase), GSH (reduced glutathione) and GSSG (oxidized glutathione) levels. Taken together, the metabolic interferences and oxidative damages in ACE20 group were significantly different from the other three exposure groups. These results help to explore the toxicity mechanism of neonicotinoid insecticides from multiple perspectives. This study provides scientific basis for evaluating toxicity of different neonicotinoid insecticides.


Assuntos
Inseticidas , Inseticidas/toxicidade , Lipidômica , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade
14.
J Prev Med Public Health ; 55(3): 280-288, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35678002

RESUMO

OBJECTIVES: One of the most widely used pesticides today is chlorpyrifos (CPF). Cytochrome P450 (CYP)2B6, the most prominent catalyst in CPF bioactivation, is highly polymorphic. The objective of our study was to evaluate the role of CYP2B6*6, which contains both 516G>T and 785A>G polymorphisms, in CPF toxicity, as represented by the concentration of 3,5,6-trichloro-2-pyridinol (TCPy), among vegetable farmers in Central Java, Indonesia, where CPF has been commonly used. METHODS: A cross-sectional study was conducted among 132 vegetable farmers. Individual socio-demographic and occupational characteristics, as determinants of TCPy levels, were obtained using a structured interviewer-administered questionnaire and subsequently used to estimate the cumulative exposure level (CEL). TCPy levels were detected with liquid chromatography-mass spectrometry. CYP2B6*6 gene polymorphisms were analyzed using a TaqMan® SNP Genotyping Assay and Sanger sequencing. Linear regression analysis was performed to analyze the association between TCPy, as a biomarker of CPF exposure, and its determinants. RESULTS: The prevalence of CYP2B6*6 polymorphisms was 31% for *1/*1, 51% for *1/*6, and 18% for *6/*6. TCPy concentrations were higher among participants with CYP2B6*1/*1 than among those with *1/*6 or *6/*6 genotypes. CYP2B6*6 gene polymorphisms, smoking, CEL, body mass index, and spraying time were retained in the final linear regression model as determinants of TCPy. CONCLUSIONS: The results suggest that CYP2B6*6 gene polymorphisms may play an important role in influencing susceptibility to CPF exposure. CYP2B6*6 gene polymorphisms together with CEL, smoking habits, body mass index, and spraying time were the determinants of urinary TCPy concentrations, as a biomarker of CPF toxicity.


Assuntos
Clorpirifos , Inseticidas , Biomarcadores , Clorpirifos/toxicidade , Estudos Transversais , Citocromo P-450 CYP2B6/genética , Fazendeiros , Humanos , Indonésia , Inseticidas/toxicidade , Polimorfismo Genético , Piridonas
15.
Huan Jing Ke Xue ; 43(6): 2987-2995, 2022 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-35686768

RESUMO

This study was conducted in response to the current situation in our country in which neonicotinoid pesticides (NNIs) are used in large quantities and their concentration in surface water is gradually increasing. Based on the species sensitivity distribution (SSD), the hazard quotient (HQ) and probabilistic risk assessment (PRA) were used to compare single and mixture risks of NNIs in the surface water in China. The target and recommended values of NNIs in China's surface water quality supervision were also presented. The results showed that:① in the single acute hazard assessment, imidacloprid (IMI) was the most harmful insecticide, and in the single chronic hazard assessment, imidacloprid (IMI) and acetamiprid (ACE) were more harmful. Furthermore, insects were the most sensitive creatures. ② Hainan province was the region with the highest single acute and chronic hazard in the study area. ③ Based on the joint probability curves of five neonicotinoids, the probability in which 5% of species would be affected by long-term exposure was approximately 91.12%. Thus, the combined ecological risk of these five neonicotinoids cannot be ignored. ④ Based on the toxicity reference value from SSD and the combined results of HQ and PRA, the regulatory values of surface water quality in China were as follows:acetamiprid (ACE) 0.04 µg·L-1, clothianidin (CLO) 0.22 µg·L-1, imidacloprid (IMI) 0.01 µg·L-1, thiacloprid (THI) 0.03 µg·L-1, and thiamethoxam (THIA) 0.24 µg·L-1. In short, the concentration of NNIs in the surface water in China has threatened the safety of aquatic organisms, and its supervision must be improved.


Assuntos
Inseticidas , Poluentes Químicos da Água , Organismos Aquáticos , China , Inseticidas/análise , Inseticidas/toxicidade , Neonicotinoides/análise , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Tiametoxam , Poluentes Químicos da Água/análise
16.
Pestic Biochem Physiol ; 184: 105059, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35715026

RESUMO

Hibernation is a short-term survival strategy for ectotherms to cope with cold weather and food shortages. The energy sources stored before hibernation are used not only in the winter, but also in preparation for reproduction. Reproductive physiology and behavior are primarily regulated by the hypothalamus-pituitary-gonad (HPG) axis. In this study, we examined endocrine hormone changes in the HPG axis of female lizards (Eremias argus) after chlorantraniliprole insecticide (CAP) exposure during hibernation. The levels of gonadotropin-releasing hormone, luteinizing hormone, follicle-stimulating hormone and progesterone were significantly decreased and the level of testosterone (T) was significantly increased after 135d experiment. This study verified the possible endocrine disrupting effects of CAP. More energy material consumption was observed in CAP treated group. Female E. argus preferred to invest energy to present survival when exposed to CAP, rather than to reserve material for following reproductive activity.


Assuntos
Hibernação , Inseticidas , Lagartos , Animais , Inseticidas/metabolismo , Inseticidas/toxicidade , ortoaminobenzoatos
17.
Pestic Biochem Physiol ; 184: 105104, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35715043

RESUMO

Cyantraniliprole, a second-generation anthranilic diamide insecticide, is widely used to control chewing and sucking pests. ATP-binding cassette transporters (ABCs) are a ubiquitous family of membrane proteins that play important roles in insect detoxification mechanisms. However, the potential effects of ABCs on cyantraniliprole-resistance remain unclear. In the present study, synergism bioassays revealed that verapamil, an ABC inhibitor, increased the toxicity of cyantraniliprole by 2.00- and 12.25-fold in the susceptible and cyantraniliprole-resistant strains of Aphis gossypii. Based on transcriptome data, the expression levels of ABCB4, ABCB5, ABCD1, ABCG4, ABCG7, ABCG13, ABCG16, ABCG17, ABCG26 and MRP12 were upregulated 1.56-, 1.32-, 1.51-, 2.03-, 1.65-, 1.50-, 4.18-, 6.07-, 4.68- and 4.69-fold, respectively, in the cyantraniliprole-resistant strain (CyR) compared to the susceptible strain (SS), as determined using RT-qPCR. Drosophila melanogaster ectopically overexpressing ABCB5, ABCG4, ABCG7, ABCG16, ABCG17, ABCG26 and MRP12 exhibited significantly increased tolerance to cyantraniliprole by 11.71-, 2.39-, 4.85-, 2.06-, 3.75-, 4.20- and 3.50-fold, respectively, with ABCB5 and ABCG family members being the most effective. Furthermore, the suppression of ABCB5, ABCG4, ABCG7, ABCG16, ABCG17, ABCG26 and MRP12 significantly increased the sensitivity of the CyR strain to cyantraniliprole. These results indicate that ABCs may play crucial roles in cyantraniliprole resistance and may provide information for shaping resistance management strategies.


Assuntos
Afídeos , Inseticidas , Transportadores de Cassetes de Ligação de ATP/genética , Animais , Drosophila melanogaster/metabolismo , Resistência a Inseticidas/genética , Inseticidas/toxicidade , Pirazóis , ortoaminobenzoatos/farmacologia
18.
Pestic Biochem Physiol ; 184: 105115, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35715054

RESUMO

Essential oils (EOs) can provide important alternatives to chemical insecticides in the control of pests. In this study, 12 EOs of native plant species from Iran were evaluated for their adulticidal activity against the house fly. In addition, we examined the insecticidal activity of Zataria multiflora and Rosmarinus officinalis EOs on adult female house flies from pyrethroid and organophosphate resistant and susceptible populations, using both fumigant and topical bioassays. The involvement of detoxification enzymes in susceptibility was investigated with synergism experiments in vivo, while the inhibitory effects of R. officinalis and Zataria multiflora EOs on the activities of cytochrome P450-dependent monooxygenases (P450s), carboxylesterases (CarEs) and glutathione S-transferases (GSTs) were determined by enzymatic inhibition assays in vitro. The EOs of Z. multiflora, Mentha pulegium, R. officinalis and Thymus vulgaris were the most effective against adults in contact topical assays, while oils extracted from Eucalyptus cinerea, Z. multiflora, Citrus sinensis, R. officinalis, Pinus eldarica and Lavandula angustifolia where the most effective in fumigant assays. Rosmarinus officinalis and Z. multiflora EOs were selected for further investigation and showed higher toxicity against a susceptible population, compared to two insecticide-resistant populations. Correlation analysis suggested cross-resistance between these EOs and pyrethroids in the resistant populations. The toxicity of both EOs on the resistant populations was synergized by three detoxification enzyme inhibitors. Further, in vitro inhibition studies showed that R. officinalis and Z. multiflora EOs more effectively inhibited the activities of the detoxification enzymes from flies of the susceptible population compared to those of the pyrethroid resistant populations. Synergistic and enzymatic assays further revealed that increased activities of P450s, GSTs, and CarEs are possibly involved in the cross-resistance between EOs and pyrethroids. Investigating the molecular mechanisms of P450s, GSTs, and CarEs in the resistance to EOs should be subject to further studies.


Assuntos
Moscas Domésticas , Inseticidas , Óleos Voláteis , Piretrinas , Animais , Resistência a Inseticidas , Inseticidas/toxicidade , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Óleos Vegetais/química , Piretrinas/toxicidade
19.
Pestic Biochem Physiol ; 184: 105126, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35715064

RESUMO

Synthetic insecticides continue to be the main strategy for managing insect pests, which are a major concern for both crop protection and public health. As nicotinic acetylcholine receptors play a central role in insect neurotransmission, they are the molecular target of neurotoxic insecticides such as neonicotinoids. These insecticides are used worldwide and have shown high efficiency in culture protection. However, the emergence of insect resistance mechanisms, and negative side-effects on non-target species have highlighted the need for a new control strategy. In this context, the use of insecticide mixtures with synergistic effects have been used in order to decrease the insecticide dose, and thus delay the selection of resistance-strains, and limit their negative impact. In this review, we summarize the available data concerning the mode of action of neonicotinoid mixtures, as well as their toxicity to various insect pests and non-target species. We found that insecticide mixtures containing neonicotinoids may be an effective strategy for limiting insect pests, and in particular resistant strains, although they could also negatively impact non-target species such as pollinating insects.


Assuntos
Inseticidas , Receptores Nicotínicos , Animais , Insetos , Resistência a Inseticidas , Inseticidas/toxicidade , Neonicotinoides/toxicidade
20.
Pestic Biochem Physiol ; 184: 105132, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35715070

RESUMO

Deltamethrin is one of the most effective pyrethroid compounds used in stored product protection to control a wide range of pests. However, the development of resistance to deltamethrin in many pest species has been reported and useful research to overcome this problem is required. The present study investigated the possible synergistic effect of a commercial formulation of a mixture of the short chain fatty acids, octanoic, nonanoic and decanoic acid, in a formulation called "C8910" on the lethal activity of deltamethrin against susceptible (Lab-S) and relatively pyrethroid-resistant (Pyr-R) strains of T. castaneum. The possible mechanisms of synergism were studied by investigating the inhibitory effect of C8910 on the activity of detoxification enzymes including cytochrome P450s, esterases, and glutathione S-transferases (GST). In addition, the possible role of C8910 in enhancement of cuticular penetration of deltamethrin through insect cuticle was studied using GC analysis. The results showed that C8910 enhanced the toxicity of deltamethrin at mixing ratios of 1:5 and 1:10 against the Lab-S strain after 24 and 48 h of exposure, and synergistic factors (SF) ranged between 5.69 and 13.59. C8910 also showed greater synergism on the deltamethrin toxicity against the resistant strain than the susceptible one after 24 and 48 h of treatment at 1:5 and 1:10 ratios with SF values ranging from 22.82 and 47.16. C8910 showed strong inhibition of cytochrome P450 of rat microsomal fraction with IC50 value of 6.24 mM. Meanwhile, C8910 inhibited the activity of general esterases in Lab-S and Pyr-R strains with IC50 values of 26.22 and 51.73 mM, respectively. However, weak inhibition of GST activity was observed with inhibition of 52.0 and 22.6% at concentration of 100 mM of C8910 for Lab-S and Pyr-R, respectively. In addition, the results showed no significant difference between the unpenetrated amounts of deltamethrin when insects were treated with deltamethrin alone or with deltamethrin+C8910 (1:20) through the insect cuticle. Results suggested that the synergism between C8910 and deltamethrin could be related to the ability of C8910 to inhibit the detoxification enzymes such as cytochrome P450 and esterases. Therefore, C8910 could be a promising synergist to enhance deltamethrin toxicity and to be a possible natural alternative for conventional synergists such as piperonyl butoxide.


Assuntos
Besouros , Inseticidas , Piretrinas , Tribolium , Animais , Sistema Enzimático do Citocromo P-450 , Esterases , Ácidos Graxos Voláteis/farmacologia , Resistência a Inseticidas , Inseticidas/toxicidade , Nitrilas/farmacologia , Piretrinas/farmacologia , Ratos
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