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1.
J Hazard Mater ; 424(Pt A): 127291, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34583156

RESUMO

Pesticides can accumulate throughout the food chain to potentially endanger human health. Although molecular hydrogen (H2) is widely used in industry and medicine, its application in agriculture is just beginning. This study showed that H2 enhances the degradation of the fungicide chlorothalonil (CHT) in plants, but does not reduce its antifungal efficacy. Pharmacological evidence confirmed the contribution of H2-stimulated brassinosteroids (BRs) in the above responses. The genetic increased endogenous H2 with overexpression of hydrogenase 1 gene (CrHYD1) from Chlamydomonas reinhardtii in Arabidopsis not only increased BRs levels, but also eventually intensified the degradation of CHT. Expression of genes encoding some enzymes responsible for detoxification in tomato and Arabidopsis were also stimulated. Contrasting responses were observed after the pharmacological removal of endogenous BR. We further proved that H2 control of CHT degradation was relatively universal, with at least since its degradation in Chinese cabbage, cucumber, radish, alfalfa, rice, and rapeseed were differentially enhanced by H2. Collectively, above results clearly indicated that both exogenously and endogenously applied with H2 could stimulate degradation of CHT partially via BR-dependent detoxification. These results may open a new window for environmental-friendly hydrogen-based agriculture.


Assuntos
Brassinosteroides , Regulação da Expressão Gênica de Plantas , Humanos , Hidrogênio , Nitrilas/toxicidade
2.
Ecotoxicol Environ Saf ; 223: 112565, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34358930

RESUMO

The impairments of maternal fenvalerate exposure have been well documented in previous study, but little was known about the effects of paternal fenvalerate exposure. The current study aimed to assess the effects of paternal fenvalerate exposure on spatial cognition and hippocampus across generations. Adult male mice (F0) were orally administered with fenvalerate (0, 2 or 20 mg/kg) for 5 weeks. F0 males were mated with untreated-females to generate F1 generation. F1 males were mated with F1 control females to generate F2 generation. For F1 and F2 adult offspring, spatial learning and memory were detected by Morris water maze. Results showed that spatial learning and memory were impaired in F1 females but not F1 males derived from F0 males exposed to 20 mg/kg FEN. Furthermore, significant impairment of spatial learning and memory were found in F2 females but not F2 males derived from F0 males exposed to 20 mg/kg FEN. As expected, histopathology showed that neural density in hippocampal CA3 region was reduced in F1 and F2 females but not F1 and F2 males derived from F0 males exposed to 20 mg/kg FEN. Mechanistically, hippocampal thyroid hormone receptor alpha1 (TRα1) was down-regulated in F1 and F2 females derived from F0 males exposed to 20 mg/kg FEN. Correspondingly, hippocampal brain-derived neurotrophic factor, tropomyosin receptor kinase B and p75 neurotrophin receptor, three downstream genes of TR signaling, were down-regulated in F1 and F2 females. Taken together, the present study firstly found that paternal fenvalerate exposure transgenerationally impaired spatial cognition in a gender-dependent manner. Hippocampal TR signaling may, at least partially, contribute to the process of cognitive impairment induced by paternal fenvalerate exposure. Further exploration in the mode of action of fenvalerate is critically important to promote human health and environmental safety.


Assuntos
Piretrinas , Animais , Cognição , Feminino , Hipocampo , Masculino , Camundongos , Nitrilas/toxicidade , Piretrinas/toxicidade
3.
Fish Shellfish Immunol ; 116: 140-149, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34256134

RESUMO

Most antibiotics, insecticides, and other chemicals used in agricultural and fishery production tend to persist in the environment. Fenvalerate, sulfide gatifloxacin, and ridomil are widely used in aquaculture as antibacterial, antifungal, and antiparasitic drugs; however, their toxicity mechanism remains unclear. Thus, we herein analyzed the effects of these three drugs on the hepatopancreas of Procambarus clarkii at the transcriptome level. Twelve normalized cDNA libraries were constructed using RNA extracted from P. clarkii after treatment with fenvalerate, sulfide gatifloxacin, or ridomil and from an untreated control group, followed by Kyoto Encyclopedia of Genes and Genomes pathway analysis. In the control vs fenvalerate and control vs sulfide gatifloxacin groups, 14 and seven pathways were significantly enriched, respectively. Further, the effects of fenvalerate and sulfide gatifloxacin were similar on the hepatopancreas of P. clarkii. We also found that the expression level of genes encoding senescence marker protein-30 and arylsulfatase A was downregulated in the sulfide gatifloxacin group, indicating that sulfide gatifloxacin accelerated the apoptosis of hepatopancreatocytes. The expression level of major facilitator superfamily domain containing 10 was downregulated, implying that it interferes with the ability of the hepatopancreas to metabolize drugs. Interestingly, we found that Niemann pick type C1 and glucosylceramidase-ß potentially interact with each other, consequently decreasing the antioxidant capacity of P. clarkii hepatopancreas. In the fenvalerate group, the downregulation of the expression level of xanthine dehydrogenase indicated that fenvalerate affected the immune system of P. clarkii; moreover, the upregulation of the expression level of pancreatitis-associated protein-2 and cathepsin C indicated that fenvalerate caused possible inflammatory pathological injury to P. clarkii hepatopancreas. In the ridomil group, no pathway was significantly enriched. In total, 21 genes showed significant differences in all three groups. To conclude, although there appears to be some overlap in the toxicity mechanisms of fenvalerate, sulfide gatifloxacin, and ridomil, further studies are warranted.


Assuntos
Alanina/análogos & derivados , Antibacterianos/toxicidade , Astacoidea/efeitos dos fármacos , Fungicidas Industriais/toxicidade , Gatifloxacina/toxicidade , Inseticidas/toxicidade , Nitrilas/toxicidade , Piretrinas/toxicidade , Poluentes Químicos da Água/toxicidade , Alanina/toxicidade , Animais , Astacoidea/genética , Perfilação da Expressão Gênica , Hepatopâncreas/efeitos dos fármacos , Hepatopâncreas/metabolismo , Transcriptoma/efeitos dos fármacos
4.
Pestic Biochem Physiol ; 177: 104905, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34301366

RESUMO

The sulfuryl transfer reaction catalyzed by cytosolic sulfotransferase (SULT) is one of the major conjugating pathways responsible for the detoxification and subsequent elimination of xenobiotics, however, functional characterization of insect SULTs is still limited. In this study, cDNA encoding a cytosolic sulfotransferase, named TcSULT1, was cloned from the red flour beetle, Tribolium castaneum. Sequence analysis revealed that TcSULT1 had the conserved signature sequences of SULTs, and shared moderate amino acid identities with Bombyx mori and Drosophila SULTs. Analysis of the transcription level showed that TcSULT1 was highly expressed in head, epidermis and malpighian tube, and upregulated at 4 h after exposure to deltamethrin. Knockdown of TcSULT1 significantly increased the susceptibility of beetles to deltamethrin. Both RNAi and dual-luciferase assay revealed that the transcription factor TcCncC regulates the expression of TcSULT1. These data provides insights into the function and regulatory mechanism of insect SULTs.


Assuntos
Piretrinas , Tribolium , Animais , Proteínas de Insetos/genética , Nitrilas/toxicidade , Piretrinas/toxicidade , Sulfotransferases/genética , Tribolium/genética
5.
Environ Toxicol Pharmacol ; 87: 103697, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34216793

RESUMO

Herbicides may pose considerable danger to non-target aquatic organisms and further threaten human health. The present investigation was aimed to assess the effects of 2-methyl-4-chlorophenoxy acetic acid (MCPA-Na) on Cyprinus carpio embryos. Embryos were exposed to six concentrations of MCPA-Na (0, 52, 54, 56, 58 and 60 mg/L) for 96 h. A series of symptoms were observed in developmental embryos during MCPA-Na exposure, including increased death, hatching inhibited and morphological deformities. Further, MCPA-Na exposure leading to a series of morphological changes (pericardial edema, tail deformation, and spine deformation) in embryos, which were consistent with modifications in the associated genes. In this work, we also investigated the joint toxicity of herbicides (MCPA-Na and cyhalofop-butyl) commonly used in paddy fields on carp embryos, using the 96 h-LC50 of herbicides (59.784 mg/L MCPA-Na and 1.472 mg/L cyhalofop-butyl) and confirmed that a synergistic effect existing in the binary mixtures.


Assuntos
Ácido 2-Metil-4-clorofenoxiacético/toxicidade , Butanos/toxicidade , Carpas , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Herbicidas/toxicidade , Nitrilas/toxicidade , Teratógenos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Carpas/anormalidades , Carpas/genética , Carpas/crescimento & desenvolvimento , Sinergismo Farmacológico , Embrião não Mamífero/anormalidades , Feminino , Expressão Gênica/efeitos dos fármacos , Masculino , Coluna Vertebral/anormalidades , Cauda/anormalidades
6.
J Med Toxicol ; 17(3): 309-311, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34075549

RESUMO

INTRODUCTION: Several overdoses of the antiepileptic drug perampanel have been reported in adults, but very few have been reported in children. We report the case of an observed exploratory ingestion of perampanel in a 2-year-old child that resulted in ataxia and prolonged coma. CASE REPORT: A previously healthy 2-year-old female patient presented to the emergency department (ED) 30 minutes after the witnessed ingestion of 30 mg of perampanel (2 mg/kg). Within minutes of ingestion, she displayed ataxia and inability to walk. Upon ED presentation, she had normal vital signs but was minimally responsive with physical stimulation. Naloxone was given without response. She was intubated because of profound central nervous system depression and transferred to a pediatric tertiary care facility. She remained intubated with no pharmacological sedation. Physical exam showed a horizontal nystagmus. Detailed neurologic examination of ataxia and coordination was not possible, and she did not demonstrate hyperreflexia, clonus, or rigidity. Her mental status gradually improved, and she was extubated approximately 72 hours after exposure. After extubation, the patient still exhibited truncal ataxia and did not return to baseline until 96 hours post ingestion. Serum drawn approximately 16 hours after exposure showed 870 ng/mL perampanel (ref < 20 ng/mL). She remained hemodynamically stable throughout her hospital course, despite protracted depressed mental status. DISCUSSION: Given the severity of our patient's presentation, pediatric patients showing symptoms of perampanel overdose should be triaged to the ED for evaluation in anticipation of a prolonged clinical course with decreased consciousness and hypoventilation.


Assuntos
Anticonvulsivantes/toxicidade , Ataxia/induzido quimicamente , Coma/induzido quimicamente , Overdose de Drogas/tratamento farmacológico , Naloxona/uso terapêutico , Nitrilas/toxicidade , Piridonas/toxicidade , Pré-Escolar , Feminino , Humanos , Resultado do Tratamento
10.
Environ Health ; 20(1): 58, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33980260

RESUMO

BACKGROUND: At a regional or continental scale, the characterization of environmental health inequities (EHI) expresses the idea that populations are not equal in the face of pollution. It implies an analysis be conducted in order to identify and manage the areas at risk of overexposure where an increasing risk to human health is suspected. The development of methods is a prerequisite for implementing public health activities aimed at protecting populations. METHODS: This paper presents the methodological framework developed by INERIS (French National Institute for Industrial Environment and Risks) to identify a common framework for a structured and operationalized assessment of human exposure. An integrated exposure assessment approach has been developed to integrate the multiplicity of exposure pathways from various sources, through a series of models enabling the final exposure of a population to be defined. RESULTS: Measured data from environmental networks reflecting the actual contamination of the environment are used to gauge the population's exposure. Sophisticated methods of spatial analysis are applied to include additional information and take benefit of spatial and inter-variable correlation to improve data representativeness and characterize the associated uncertainty. Integrated approaches bring together all the information available for assessing the source-to-human-dose continuum using a Geographic Information System, multimedia exposure and toxicokinetic model. DISCUSSION: One of the objectives of the integrated approach was to demonstrate the feasibility of building complex realistic exposure scenarios satisfying the needs of stakeholders and the accuracy of the modelling predictions at a fine spatial-temporal resolution. A case study is presented to provide a specific application of the proposed framework and how the results could be used to identify an overexposed population. CONCLUSION: This framework could be used for many purposes, such as mapping EHI, identifying vulnerable populations and providing determinants of exposure to manage and plan remedial actions and to assess the spatial relationships between health and the environment to identify factors that influence the variability of disease patterns.


Assuntos
Exposição Ambiental , Medição de Risco/métodos , Benzoatos/urina , Saúde Ambiental , Contaminação de Alimentos , Sistemas de Informação Geográfica , Humanos , Inseticidas/farmacocinética , Inseticidas/toxicidade , Modelos Teóricos , Nitrilas/farmacocinética , Nitrilas/toxicidade , Piretrinas/farmacocinética , Piretrinas/toxicidade
11.
Anal Sci ; 37(11): 1497-1503, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33867399

RESUMO

User-friendly fingerprint powders, namely efficient, low-cost and nontoxic ones, are always desirable for the development of latent fingerprints (LFPs). Here, we described the use of pristine graphic carbon nitride quantum dots (g-C3N4 QDs) as a new kind of user-friendly fingerprint powder. The g-C3N4 QDs can be easily prepared from urea and sodium citrate precursors through low temperature solid-phase reaction. Due to their good optical properties and selective interactions with secretion residuals, the g-C3N4 QDs powders were exploited to develop LFPs on different substrates by the powder dusting technique. The LFP images on a plastic bag exhibited a high ridge and furrow contrast ratio, allowing for easy identification of level 1 - 3 details of LFPs. This work indicates that the g-C3N4 QD powders provide good performance for LFP visualization and is likely to be adopted for some applications in forensic investigations.


Assuntos
Pontos Quânticos , Nitrilas/toxicidade
12.
Food Chem Toxicol ; 153 Suppl 1: 112180, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33839217

RESUMO

The existing information supports the use of this material as described in this safety assessment. 6-Nonenenitrile, (Z)- (9CI) was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data from read-across analog 3-(cis-3-hexenyloxy)propanenitrile (CAS # 142653-61-0) show that 6-nonenenitrile, (Z)- (9CI) is not expected to be genotoxic. The repeated dose, reproductive, and local respiratory toxicity endpoints were evaluated using the Threshold of Toxicological Concern (TTC) for a Cramer Class III material, and the exposure to 6-nonenenitrile, (Z)- (9CI) is below the TTC (0.0015 mg/kg/day, 0.0015 mg/kg/day, and 0.47 mg/day, respectively). Data from read-across analog 3-(cis-3-hexenyloxy)propanenitrile (CAS # 142653-61-0) show that there are no safety concerns for 6-nonenenitrile, (Z)- (9CI) for skin sensitization under the current declared levels of use. The phototoxicity/photoallergenicity endpoints were evaluated based on ultraviolet (UV) spectra; 6-nonenenitrile, (Z)- (9CI) is not expected to be phototoxic/photoallergenic. The environmental endpoints were evaluated; 6-nonenenitrile, (Z)- (9CI) was found not to be Persistent, Bioaccumulative, and Toxic (PBT) as per the International Fragrance Association (IFRA) Environmental Standards, and its risk quotients, based on its current volume of use in Europe and North America (i.e., Predicted Environmental Concentration/Predicted No Effect Concentration [PEC/PNEC]), are <1.


Assuntos
Nitrilas/toxicidade , Odorantes , Perfumes/toxicidade , Animais , Bactérias/efeitos dos fármacos , Qualidade de Produtos para o Consumidor , Determinação de Ponto Final , Humanos , Nitrilas/química , Medição de Risco , Estereoisomerismo
13.
Ecotoxicol Environ Saf ; 217: 112234, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33864981

RESUMO

The toxicity tests of nineteen commonly used pesticides were carried out to compare the sensitivity differences between predatory mite Neoseiulus cucumeris and its prey Tetranychus cinnabarinus by a "leaf spray method" in laboratory microcosms. For two avermectins, emamectin benzoate and abamectin, exhibited high bioactivity against T. cinnabarinusf with LR50 values of 0.04 and 0.05 g a.i./ha, respectively, but these two insecticides showed the opposite toxic effects to N. cucumeris. These two agents showed strong selectivity for the two test species with Selective Toxicity Rate (STR) values of 950 and 620, respectively. However, for five neonicotinoids, the LR50s of dinotefuran, thiamethoxam, imidacloprid, and acetamiprid were all greater than the recommended rates in the field except for clothianidin, and they showed no obvious toxicity difference to the two species with STR values ranging from 0.58 to 2.00. For two organophosphates, malathion is more toxic to N. cucumeris than T. cinnabarinus, however, dimethoate showed a higher toxic effect on T. cinnabarinus. In addition, the toxicity of four pyrethroids, bifenthrin, deltamethrin, cyhalothrin and gamma-cyhalothrin to N. cucumeris was higher than that of T. cinnabarinus, except for alpha-cypermethrin. For five acaricides, spirodiclofen, spirotetramat and pyridaben had no obvious selectivity to the two organisms, while diafenthiuron and chlorfenapyr were found to be highly toxic to T. cinnabarinus than N. cucumeris with STR values of 14.2 and 68.5, respectively. Thus, some pesticides above-mentioned like emamectin benzoate, abamectin, diafenthiuron and chlorfenapyr exhibited potential to be used in the management programs of T. cinnabarinus, especially in organically based production systems where there are fewer chemical control measures available, which need to combine with natural enemies to achieve the best control effect.


Assuntos
Praguicidas/toxicidade , Aranhas/fisiologia , Tetranychidae/fisiologia , Acaricidas/farmacologia , Animais , Guanidinas/toxicidade , Ácaros/efeitos dos fármacos , Neonicotinoides/toxicidade , Nitrilas/toxicidade , Nitrocompostos/toxicidade , Piretrinas/farmacologia , Piretrinas/toxicidade , Tiazóis/toxicidade
14.
Chemosphere ; 278: 130423, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33819891

RESUMO

Deltamethrin (DTM) is a pyrethroid insecticide widely used for agricultural purposes. Exposure to DTM has proven to be harmful to humans, but whether low, environmental concentrations of this pesticide also poses a threat to wild mammals is still unknown. In Neotropical areas, bats play important roles in contributing to forest regeneration. We investigated the effects of DTM exposure on the reproductive function of male Neotropical fruit-eating bats (Artibeus lituratus), known for contributing to reforestation through seed dispersal in Neotropical Forests. Bats were assigned to 3 groups: control (fed with papaya); DTM2 (fed with papaya treated with DTM at 0.02 mg/kg) and DTM4 (fed with papaya treated with DTM at 0.04 mg/kg) for seven days. Bats from DTM2 and DTM4 groups showed increased testicular levels of nitric oxide and superoxide dismutase and catalase activities. The germinal epithelium from DTM4 bats showed non-viable cells and cell desquamation, indicating microscopic lesions and Leydig cells atrophy. Our results demonstrate the onset of cell degeneration that may affect the reproductive function in DTM exposed bats.


Assuntos
Quirópteros , Piretrinas , Animais , Frutas , Humanos , Masculino , Nitrilas/toxicidade , Piretrinas/toxicidade
15.
Artigo em Inglês | MEDLINE | ID: mdl-33862233

RESUMO

Deltamethrin (Del), a commonly used broad-spectrum insecticide, has been reported to have a toxic effect on aquatic animals, but knowledge in freshwater prawns is limited. This study revealed that Del is highly toxic to Macrobrachium nipponens with the 24 h, 48 h, 72 h, and 96 h LC50 values to be 0.268, 0.165, 0.104, and 0.066 µg/L, respectively. To further investigate the toxic effect of Del in M. nipponense and the reversibility of damage, prawns were exposed to 0.05 µg/L Del for four days and then transferred into fresh water for seven days. Histopathological examination, oxidative stress, hepatopancreas function, respiration system, and immune system were analyzed through multiple biomarkers. Results showed that Del exposure caused severe histopathological damage to hepatopancreas and gill in M. nipponense, and the prominent decrease of acid phosphatase (ACP) and alkaline phosphatase (AKP) activity further enhanced the hepatopancreas damage; the accumulation of malonaldehyde (MDA) and hydrogen peroxide (H2O2), and the decrease of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity, indicated severe oxidative stress caused by Del. Besides, Del exposure also induced remarkably increased lactic acid (LD) level, decreased lactate dehydrogenase (LDH) activity, and decreased expression of immune-related genes, which demonstrated the respiration disruption and immunosuppression caused by Del. After 7-day decontamination in freshwater, the indicator of hepatopancreas function (ACP and AKP activity) and respiration (LD level and LDH activity) improved to the control group level. However, the histopathological damage and the biomarker in oxidative stress and immune system did not recover to the initial level.


Assuntos
Inseticidas/toxicidade , Nitrilas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Palaemonidae/efeitos dos fármacos , Piretrinas/toxicidade , Animais , Brânquias/efeitos dos fármacos , Brânquias/patologia , Hepatopâncreas/efeitos dos fármacos , Hepatopâncreas/patologia , Palaemonidae/imunologia , Poluentes Químicos da Água/toxicidade
16.
Proc Biol Sci ; 288(1947): 20202922, 2021 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-33784861

RESUMO

Numerous threats are putting pollinator health and essential ecosystem pollination services in jeopardy. Although individual threats are widely studied, their co-occurrence may exacerbate negative effects, as posited by the multiple stressor hypothesis. A prominent branch of this hypothesis concerns pesticide-pathogen co-exposure. A landscape analysis demonstrated a positive association between local chlorothalonil fungicide use and microsporidian pathogen (Nosema bombi) prevalence in declining bumblebee species (Bombus spp.), suggesting an interaction deserving further investigation. We tested the multiple stressor hypothesis with field-realistic chlorothalonil and N. bombi exposures in worker-produced B. impatiens microcolonies. Chlorothalonil was not avoided in preference assays, setting the stage for pesticide-pathogen co-exposure. However, contrary to the multiple stressor hypothesis, co-exposure did not affect survival. Bees showed surprising tolerance to Nosema infection, which was also unaffected by chlorothalonil exposure. However, previously fungicide-exposed infected bees carried more transmission-ready spores. Our use of a non-declining bumblebee and potential higher chlorothalonil exposures under some scenarios could mean stronger individual or interactive effects in certain field settings. Yet, our results alone suggest consequences of pesticide co-exposure for pathogen dynamics in host communities. This underlies the importance of considering both within- and between-host processes when addressing the multiple stressor hypothesis in relation to pathogens.


Assuntos
Ecossistema , Nosema , Animais , Abelhas , Nitrilas/toxicidade
17.
PLoS One ; 16(3): e0247756, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33667239

RESUMO

Monitoring pesticide resistance is essential for effective and sustainable agricultural practices. Bioassays are the basis for pesticide-resistance testing, but devising a reliable and reproducible method can be challenging because these tests are carried out on living organisms. Here, we investigated five critical parameters and how they affected the evaluation of resistance to the organophosphate phosmet or the pyrethroid lambda-cyhalothrin using a tarsal-contact protocol on Drosophila suzukii, a worldwide invasive pest. Three of the parameters were related to insect biology: (i) sex, (ii) age of the imago (adult stage) and (iii) genetic diversity of the tested population. The two remaining parameters were linked to the experimental setup: (iv) the number of individuals tested per dose and (v) the duration of exposure to the active ingredient. Results showed that response to insecticide differed depending on sex, males being twice as susceptible to phosmet as females. Age principally affected young females' susceptibility to phosmet, because 0-24 hour-old flies were twice as susceptible as 24-48 hour-old and 72-96 hour-old females. Genetic diversity had no observable effect on resistance levels. The precision and accuracy of the median lethal dose (LD50) were greatly affected by the number of individuals tested per dose with a threshold effect. Finally, optimal duration of exposure to the active ingredient was 24 h, as we found an underestimation of mortality when assessed between 1 and 5 h after exposure to lambda-cyhalothrin. None of the main known point mutations on the para sodium channel gene associated with a knockdown effect were observed. Our study demonstrates the importance of calibrating the various parameters of a bioassay to develop a reliable method. It also provides a valuable and transferable protocol for monitoring D. suzukii resistance worldwide.


Assuntos
Bioensaio , Drosophila/efeitos dos fármacos , Drosophila/genética , Resistência a Inseticidas/genética , Inseticidas/toxicidade , Espécies Introduzidas , Animais , Feminino , Variação Genética , Controle de Insetos , Dose Letal Mediana , Masculino , Nitrilas/toxicidade , Fosmet/toxicidade , Piretrinas/toxicidade
18.
Toxicol In Vitro ; 73: 105132, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33662517

RESUMO

Next Generation Risk Assessment (NGRA) can use the so-called Dietary Comparator Ratio (DCR) to evaluate the safety of a defined exposure to a compound of interest. The DCR compares the Exposure Activity Ratio (EAR) for the compound of interest, to the EAR of an established safe level of human exposure to a comparator compound with the same putative mode of action. A DCR ≤ 1 indicates the exposure evaluated is safe. The present study aimed at defining adequate and safe comparator compound exposures for evaluation of anti-androgenic effects, using 3,3-diindolylmethane (DIM), from cruciferous vegetables, and the anti-androgenic drug bicalutamide (BIC). EAR values for these comparator compounds were defined using the AR-CALUX assay. The adequacy of the new comparator EAR values was evaluated using PBK modelling and by comparing the generated DCRs of a series of test compound exposures to actual knowledge on their safety regarding in vivo anti-androgenicity. Results obtained supported the use of AR-CALUX-based comparator EARs for DCR-based NGRA for putative anti-androgenic compounds. This further validates the DCR approach as an animal free in silico/in vitro 3R compliant method in NGRA.


Assuntos
Antagonistas de Androgênios/toxicidade , Anilidas/toxicidade , Indóis/toxicidade , Modelos Biológicos , Nitrilas/toxicidade , Receptores Androgênicos/metabolismo , Medição de Risco/métodos , Compostos de Tosil/toxicidade , Adulto , Antagonistas de Androgênios/farmacocinética , Anilidas/farmacocinética , Alternativas aos Testes com Animais , Bioensaio , Linhagem Celular Tumoral , Exposição Ambiental , Humanos , Indóis/farmacocinética , Masculino , Nitrilas/farmacocinética , Compostos de Tosil/farmacocinética
19.
Environ Sci Pollut Res Int ; 28(29): 39501-39512, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33754270

RESUMO

Although pesticides are typically used to limit pest population, the diversity and nature of their unintentional effects on non-target organisms remain unclear. Better understanding these effects requires to carry out risk assessments on key physiological and behavioral processes specific to beneficial insects. In this study, we addressed this question by exposing mothers of the European earwig (a beneficial insect) to two sublethal doses of deltamethrin (a common pesticide in agriculture) during family life and measured the short- and long-term effects on a series of behavioral, physiological, and reproductive traits. Somewhat surprisingly, our results first revealed that high and low doses of deltamethrin enhanced mothers' future reproduction by augmenting their likelihood to produce a second clutch, shortening the number of days until its production, and increasing the resulting number of eggs and their hatching rate. Conversely, the high dose of deltamethrin was detrimental, as it limited maternal brood defence, and reduced food consumption and expression of self-grooming. Finally, other traits were independent of deltamethrin exposure, such as three proxies of family interactions (i.e., distance to the brood, occurrence, and duration of mother-offspring contacts), mothers' walking distance, and mother weight gain during family life. Our study overall demonstrates that sublethal exposure to a pesticide such as deltamethrin can have both positive and negative effects on non-target beneficial insects. It thus emphasizes that focusing on narrow parameters can lead to misleading conclusions about the unintended impacts of pesticides in treated agro-ecosystems and call for better considering this parameters diversity in integrated pest management programs.


Assuntos
Inseticidas , Piretrinas , Animais , Ecossistema , Inseticidas/toxicidade , Nitrilas/toxicidade , Piretrinas/toxicidade , Reprodução
20.
Ecotoxicol Environ Saf ; 214: 112105, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33690003

RESUMO

Eusocial Apis mellifera colonies depend on queen longevity and brood viability to survive, as the queen is the sole reproductive individual and the maturing brood replenishes the shorter-lived worker bees. Production of many crops rely on both pesticides and bee pollination to improve crop quantity and quality, yet sublethal impacts of this pesticide exposure is often poorly understood. We investigated the resiliency of queens and their brood after one month of sublethal exposure to field relevant doses of pesticides that mimic exposure during commercial pollination contracts. We exposed full size colonies to pollen contaminated with field-relevant doses of the fungicides (chlorothalonil and propicanizole), insecticides (chlorypyrifos and fenpropathrin) or both, noting a significant reduction in pollen consumption in colonies exposed to fungicides compared to control. While we found no difference in the total amount of pollen collected per colony, a higher proportion of pollen to non-pollen foragers was detected in all pesticide exposed colonies. After ceasing treatments, we measured brood development, discovering a significant increase in brood loss and/or cannibalism across all pesticide exposed groups. Sublethal pesticide exposure in general was linked to reduced production of replacement workers and a change in protein acquisition (pollen vs. non-pollen foraging). Fungicide exposure also resulted in increased loss of the reproductive queen.


Assuntos
Abelhas/efeitos dos fármacos , Clorpirifos/toxicidade , Fungicidas Industriais/toxicidade , Inseticidas/toxicidade , Nitrilas/toxicidade , Pólen , Piretrinas/toxicidade , Triazóis/toxicidade , Animais , Abelhas/fisiologia , Feminino , Polinização , Reprodução/efeitos dos fármacos
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