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1.
Ecotoxicol Environ Saf ; 213: 112059, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33647747

RESUMO

Tibial dyschondroplasia (TD) is a metabolic disease of young poultry that affects bone andcartilage's growth. It mostly occurs in broilers due to thiram toxicity in the feed. In this disease, tibial cartilage is not yet ripe for ossification, but it also results in lameness, death, and moral convictions of commercial poultry due to numerous apoptotic changes on cell level. These changes serve a cardinal role in this situation. Many potential problems indicate that chlorogenic acid (CGA) performs an extensive role in controlling apoptosis's perception. However, the actual role of CGA in TD affected chondrocytes in-vitro is still unidentified. The current study investigates the imperceptible insight of CGA on chondrocyte's apoptosis via B-cell lymphoma 2 (Bcl-2), Bcl-2 associated x-protein (Bax), and Caspase-3 with CD147 signalling. The expression of these markers was investigated by Immunofluorescence, western blot analysis, and reverse transcription-quantitative polymerase chain (RT-qPCR). Chondrocytes from the growth plate of tibia were isolated, cultured, and processed. A sub-lethal thiram (2.5 µg/mL) was used to induce cytotoxicity and then treated with an optimum dose (40 µg/ mL) of CGA. According to the results, thiram distorted chondrocyte cells with enhanced apoptotic rate. But, in case of CGA, high expression of CD147 enhanced cell viability of chondrocytes, accompanied by downregulation of Bax/Caspase-3 signalling with the upregulation of Bcl-2. The first possibility has ruled out in the present study by the observation that the cells apoptosis marker, Caspase-3 showed a significant change in CD147 overexpressing cells. Conversely, immunodepletion of CD147 with enhanced cleavage of Caspase-3, indicating the activation of apoptosis in chondrocytes cells. Therefore, these findings suggest a novel insight about CD147 in thiram induced TD about the regulation of Bcl-2/Bax/Caspase-3 apoptosis-signalling axis.


Assuntos
Basigina/metabolismo , Fungicidas Industriais/toxicidade , Tiram/toxicidade , Animais , Apoptose , Caspase 2 , Caspase 3/metabolismo , Diferenciação Celular , Sobrevivência Celular , Galinhas/metabolismo , Ácido Clorogênico , Condrócitos/metabolismo , Cisteína Endopeptidases , Lâmina de Crescimento/patologia , Osteocondrodisplasias/tratamento farmacológico , Tíbia/patologia , Regulação para Cima , Proteína X Associada a bcl-2/metabolismo
2.
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 , Nitrilos/toxicidade , Pólen , Piretrinas/toxicidade , Triazóis/toxicidade , Animais , Abelhas/fisiologia , Feminino , Polinização , Reprodução/efeitos dos fármacos
3.
Environ Res ; 195: 110829, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33548298

RESUMO

Neurogenesis plays a crucial role during neurodevelopment and its dysfunction can lead to neurodevelopmental disorders. A recent hypothesis stipulates that exogenous factors could corrupt this process and predispose to neurodegenerative disorders later in life. The presence of pesticide residues in the diet represents a threat of which we have recently become aware of. Indeed, they could corrupt neurogenesis, especially during gestation, potentially leading to impaired neuronal and synaptic functions. Since the effects of this low-noise contamination have not yet been evaluated on the neurodevelopment, we investigated the impact of fungicide residues on WT mice exposed throughout gestation. Thus, mice were exposed to fungicides, cyprodinil, mepanipyrim and pyrimethanil, alone at 0.1 µg/L during gestation until P3. Besides, another group was exposed to a cocktail of these three fungicides (0.1 µg/L each) for the same time. Exposure was performed through drinking water at the regulatory limit dose of the European countries (0.1 µg/L). No general toxicity was observed in neonates on body and brain weight upon fungicide exposure. However, results showed that gestational exposure to fungicide residues substantially promoted an increase of neural precursor cells at P3. This corrupted neurogenesis was linked to increased levels of ß-catenin, likely through the crosstalk of the PI3K/Akt and Wnt/ß-catenin pathways, both involved in cell proliferation. Fungicide exposure also altered protein expression of PSD95 and NMDA receptors in P3 neonates, two targets of the ß-catenin signaling pathway. Adult neural stem cell extractions from mice treated with the fungicide cocktail, showed an increase proliferation and differentiation combined with a reduction of their migration properties. In addition, in vitro studies on hippocampal primary cell cultures treated with various concentrations of fungicides showed neurotoxic effects. To conclude, corruption of neurogenesis by this chemical assault could be a fertile ground for the development of neurological diseases later in life.


Assuntos
Fungicidas Industriais , Células-Tronco Neurais , Efeitos Tardios da Exposição Pré-Natal , Animais , Proliferação de Células , Europa (Continente) , Feminino , Fungicidas Industriais/toxicidade , Camundongos , Neurogênese , Fosfatidilinositol 3-Quinases/farmacologia , Gravidez
4.
Ecotoxicol Environ Saf ; 213: 111985, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33578099

RESUMO

The rampant use of pesticides can cause serious environmental problems. They can be contaminating surface water and groundwater, affecting the surrounding micro and macro biota. In this sense, this work aimed to evaluate the effects of a tebuconazole-based fungicide through endpoints accessed in Lactuca sativa bioassays. Germinated-seeds with roots upon 2 mm were treated with a fungicide containing Tebuconazole (TBZ) as active compound. The final concentration of TBZ in the tested solutions were 0.025 (C1); 0.05 (C2); 0.1 (C3); 0.2 (C4) and 0.4 g/L (C5). L. sativa roots were exposed for 24 h to these solutions and Petri dishes containing the treated seeds were kept in incubation chamber at 24 °C. Two positive controls (PC,) the herbicide trifluralin (0.84 mg/L) and Methanesulfonate (4 ×10-4 mol/L), were applied. Distilled water was negative control (NC). The following endpoints were analyzed: root growth (RG), cytogenotoxic potential by cell cycle analysis, induction of DNA damage through TUNEL and comet assays. The obtained data were submitted to one-way variance analysis (ANOVA) and then to Tukey or Kruskal Wallis (P < 0.05) tests. The concentrations (C1, C2, C4 and C5) affected negatively the RG of L. sativa, in comparison with the NC. The mitotic index was reduced by 25% from NC to C1 and in the rest of treatments it did not present significant modifications. However, from C3 to C5 great amount of chromosome alterations were observed, in comparison with the NC. TBZ-based fungicide also induced DNA fragmentation as measured by TUNEL and comet assays. Thus, TBZ-based fungicide in some concentrations can have phytotoxic, cytotoxic and genotoxic effects in roots and meristematic cells of L. sativa.


Assuntos
Fungicidas Industriais/toxicidade , Alface/fisiologia , Triazóis/toxicidade , Bioensaio , Aberrações Cromossômicas , Ensaio Cometa , Dano ao DNA , Germinação/efeitos dos fármacos , Herbicidas/toxicidade , Meristema/efeitos dos fármacos , Índice Mitótico , Raízes de Plantas/efeitos dos fármacos , Sementes/efeitos dos fármacos , Toxicogenética
5.
Environ Pollut ; 275: 116671, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33582629

RESUMO

Strobilurins are popular fungicides used in agriculture on a global scale. Due to their widespread use as agrochemicals, they can enter aquatic environments at concentrations that can elicit adverse effects in organisms. This review synthesizes the current state of knowledge regarding the toxic effects of strobilurin fungicides on aquatic species, including algal species, Daphnia magna, and fish species, to determine risk to aquatic organisms and ecosystems. Data show that the toxicities of strobilurins vary widely across aquatic species. Strobilurins bind cytochrome bc1 in mitochondrial complex III in fungi, and as such, research in aquatic species has focused on mitochondria-related endpoints following exposures to strobilurins. In fish, studies into the activities of mitochondrial complexes and the expression of genes involved in the electron transfer chain have been conducted, converging on the theme that mitochondrial complexes and their enzymes are impaired by strobilurins. In general, the order of toxicity of strobilurins for fish species are pyraoxystrobin > pyraclostrobin ≈ trifloxystrobin > picoxystrobin > kresoxim-methyl > fluoxastrobin > azoxystrobin. In addition to mitochondrial toxicity, studies also report genotoxicity, immunotoxicity, cardiotoxicity, neurotoxicity, and endocrine disruption, and each of these events can potentially impact whole organism-level processes such as development, reproduction, and behavior. Screening data from the US Environmental Protection Agency ToxCast database supports the hypothesis that these fungicides may act as endocrine disruptors, and high throughput data suggest estrogen receptor alpha and thyroid hormone receptor beta can be activated by some strobilurins. It is recommended that studies investigate the potential for endocrine disruption by strobilurins more thoroughly in aquatic species. Based on molecular, physiological, and developmental outcomes, a proposed adverse outcome pathway is presented with complex III inhibition in the electron transfer chain as a molecular initiating event. This review comprehensively addresses sub-lethal toxicity mechanisms of strobilurin fungicides, important as the detection of strobilurins in aquatic environments suggests exposure risks in wildlife.


Assuntos
Fungicidas Industriais , Animais , Daphnia , Ecossistema , Fungicidas Industriais/análise , Fungicidas Industriais/toxicidade , Estrobilurinas/toxicidade , Peixe-Zebra
6.
Environ Pollut ; 274: 116533, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33529906

RESUMO

Commercial beekeepers in many locations are experiencing increased annual colony losses of honey bees (Apis mellifera), but the causes, including the role of agrochemicals in colony losses, remain unclear. In this study, we investigated the effects of chronic consumption of pollen containing a widely-used fungicide (Pristine®), known to inhibit bee mitochondria in vitro, which has recently been shown to reduce honey bee worker lifespan when field-colonies are provided with pollen containing field-realistic levels of Pristine®. We fed field colonies pollen with a field-realistic concentration of Pristine® (2.3 ppm) and a concentration two orders of magnitude higher (230 ppm). To challenge flight behavior and elicit near-maximal metabolic rate, we measured flight quality and metabolic rates of bees in two lower-than-normal air densities. Chronic consumption of 230 but not 2.3 ppm Pristine® reduced maximal flight performance and metabolic rates, suggesting that the observed decrease in lifespans of workers reared on field-realistic doses of Pristine®-laced pollen is not due to inhibition of flight muscle mitochondria. However, consumption of either the 230 or 2.3 ppm dose reduced thorax mass (but not body mass), providing the first evidence of morphological effects of Pristine®, and supporting the hypothesis that Pristine® reduces forager longevity by negatively impacting digestive or nutritional processes.


Assuntos
Fungicidas Industriais , Animais , Abelhas , Digestão , Fungicidas Industriais/toxicidade , Longevidade , Pólen , Tórax
7.
Chemosphere ; 272: 129618, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33465613

RESUMO

In previous articles, it was found that epoxiconazole enantiomers can persist for a long time in the environment, causing severe environmental damage. Herein, we investigated alterations in the soil microbial community and rat gut microbiota after six weeks of treatment with rac-epoxiconazole or one of its enantiomers. The selected concentrations were 1, 2, and 6 times greater than the maximum residue limits (MRLs). The rat gut microbiota relative abundance in the feces significantly changed following exposure to rac-epoxiconazole or one of its enantiomers. At the phylum level, in the R,S-, S,R-epoxiconazole, and rac-treated groups, Firmicutes presented the greatest decrease in abundance; however, Spirochaetes presented the greatest increase in abundance in the rac- and S,R-epoxiconazole-treated groups. In response to R,S-epoxiconazole, Epsilonbacteraeota presented the greatest increase in abundance. In soil samples treated with epoxiconazole, the relative abundance of the soil bacterial community also changed. Proteobacteria presented the greatest decrease in abundance in the S,R- and rac-treated samples. However, Firmicutes presented the greatest increase in abundance. In the R,S-treated soil samples, the situation was the opposite. In general, prolonged exposure to epoxiconazole at high concentrations could initiate noticeable alterations in rat gut microbiota and soil microbial diversity. R,S-epoxiconazole had improved bioactivity and less toxic effects at relatively low concentrations. Therefore, we recommend using R,S-epoxiconazole at a relatively low concentration, which is better for environmental safety.


Assuntos
Fungicidas Industriais , Microbioma Gastrointestinal , Animais , Compostos de Epóxi/toxicidade , Fungicidas Industriais/análise , Fungicidas Industriais/toxicidade , Ratos , Solo , Triazóis
8.
Chemosphere ; 272: 129577, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33465616

RESUMO

Dicarboximide fungicides mainly including procymidone, iprodione, vinclozolin, and dimethachlon are often applied as protective fungicides, 3,5-dichloroaniline (3,5-DCA) is their common metabolite in plant and environment. In this study, the acute toxicity of procymidone, iprodione and their metabolite of 3,5-DCA toward zebrafish was evaluated by semi-static method. The enrichment and metabolism of procymidone and iprodione in zebrafish were also clarified. The results indicated that procymidone and iprodione exhibited moderately toxic to adult zebrafish with the LC50 of 2.00 mg/L, 5.70 mg/L at 96 h. Both procymidone and iprodione could be metabolized to 3,5-DCA in zebrafish, which showed higher toxic to adult zebrafish with the LC50 of 1.64 mg/L at 96 h. From the perspective of histomorphology, for all treatment groups, the brain of the zebrafish was significantly damaged, while the damage to gut and gills was lighter. For procymidone, the biological concentration factor (BCF8d) were 236 and 246 at the exposure concentration of 0.2 mg/L and 0.04 mg/L, and the BCF8d were 3.2 and 2.4 for iprodione at the exposure concentration of 0.5 mg/L and 0.1 mg/L. Therefore, the procymidone and iprodione were moderate-enriched and low-enriched in zebrafish, respectively.


Assuntos
Fungicidas Industriais , Hidantoínas , Aminoimidazol Carboxamida/análogos & derivados , Compostos de Anilina , Animais , Compostos Bicíclicos com Pontes , Fungicidas Industriais/toxicidade , Peixe-Zebra
9.
Chemosphere ; 273: 129663, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33515965

RESUMO

Azoxystrobin (AZ) is a broad-spectrum synthetic fungicide widely used in agriculture globally. However, there are concerns about its fate and effects in the environment. It is reportedly transformed into azoxystrobin acid as a major metabolite by environmental microorganisms. Bacillus licheniformis strain TAB7 is used as a compost deodorant in commercial compost and has been found to degrade some phenolic and agrochemicals compounds. In this article, we report its ability to degrade azoxystrobin by novel degradation pathway. Biotransformation analysis followed by identification by electrospray ionization-mass spectrometry (MS), high-resolution MS, and nuclear magnetic resonance spectroscopy identified methyl (E)-3-amino-2-(2-((6-(2-cyanophenoxy)pyrimidin-4-yl)oxy)phenyl)acrylate, or (E)-azoxystrobin amine in short, and (Z) isomers of AZ and azoxystrobin amine as the metabolites of (E)-AZ by TAB7. Bioassay testing using Magnaporthe oryzae showed that although 40 µg/mL of (E)-AZ inhibited 59.5 ± 3.5% of the electron transfer activity between mitochondrial Complexes I and III in M. oryzae, the same concentration of (E)-azoxystrobin amine inhibited only 36.7 ± 15.1% of the activity, and a concentration of 80 µg/mL was needed for an inhibition rate of 56.8 ± 7.4%, suggesting that (E)-azoxystrobin amine is less toxic than the parent compound. To our knowledge, this is the first study identifying azoxystrobin amine as a less-toxic metabolite from bacterial AZ degradation and reporting on the enzymatic isomerization of (E)-AZ to (Z)-AZ, to some extent, by TAB7. Although the fate of AZ in the soil microcosm supplemented with TAB7 will be needed, our findings broaden our knowledge of possible AZ biotransformation products.


Assuntos
Bacillus licheniformis , Fungicidas Industriais , Aminas , Ascomicetos , Fungicidas Industriais/toxicidade , Pirimidinas , Estrobilurinas
10.
Ecotoxicol Environ Saf ; 208: 111603, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396123

RESUMO

Chlorothalonil (CLT) is a broad spectrum, and non-systemic fungicide applied in foliar structures to prevent and treat pathogens. This compound reaches to aquatic environments and affects the biota. In this context, the main goal of this study was to assess the effects of CLT at biochemical, tissular, and individual levels of biological organization using the invasive bivalve Corbicula largillierti as a bioindicator species. Clams were exposed to different sublethal concentrations (0, 10, 20 and 50 µg. L-1 CLT) for 96 h. At biochemical level, the enzymatic activity (Glutathione-s-Transferase, Catalase, Acetyl-, Butiryl- and Carboxyl-esterases) and lipid peroxidation were measured in gills and the visceral mass. Also, the digestive gland morphometry through quantitative histological indexes was registered at the tissular level. Finally, filtering activity and burial behavior at the individual level were measured. At the highest CLT concentration, the most significant changes were observed in enzymatic activity (except for butyrylcholinesterase), lipid peroxidation and in digestive gland morphometry. It was also registered increases of the filtering activity and the latency time to burial. Most of the biomarkers assessed showed significant responses under CLT exposure. Therefore, taking into account that C. largillierti was affected by CLT, it can be expected that other species could be in a potential risk if this fungicide is present in freshwater systems.


Assuntos
Corbicula/efeitos dos fármacos , Monitoramento Ambiental/métodos , Água Doce/química , Fungicidas Industriais/toxicidade , Nitrilos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Catalase/metabolismo , Corbicula/enzimologia , Relação Dose-Resposta a Droga , Fungicidas Industriais/análise , Brânquias/efeitos dos fármacos , Brânquias/enzimologia , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Nitrilos/análise , Poluentes Químicos da Água/análise
11.
Ecotoxicol Environ Saf ; 208: 111606, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396126

RESUMO

Mancozeb is a metal-containing ethylene bis-dithiocarbamate fungicide widely used in agriculture. Ethylene thiourea (ETU) is the primary metabolite of Mancozeb. Mancozeb has been associated with spontaneous abortions and abnormal menstruation in women. However, the effects of Mancozeb and ETU on embryo attachment remain unknown. The human blastocyst surrogate trophoblastic spheroids (JEG-3), endometrial epithelial surrogate adenocarcinoma cells (Ishikawa), or human primary endometrial epithelial cells (EECs) monolayer were used in the spheroid attachment models. Ishikawa and EECs were pretreated with different concentrations of Mancozeb or ETU for 48 h before the attachment assay. Gene expression profiles of Ishikawa cells were examined to understand how Mancozeb modulates endometrial receptivity with Microarray. The genes altered by Mancozeb were confirmed by qPCR and compared with the ETU treated groups. Mancozeb and ETU treatment inhibited cell viability at 10 µg/mL and 5000 µg/mL, respectively. At non-cytotoxic concentrations, Mancozeb at 3 µg/mL and ETU at 300 µg/mL reduced JEG-3 spheroid attachment onto Ishikawa cells. A similar result was observed with human primary endometrial epithelial cells. Mancozeb at 3 µg/mL modified the transcription of 158 genes by at least 1.5-fold in Microarray analysis. The expression of 10 differentially expressed genes were confirmed by qPCR. Furthermore, Mancozeb decreased spheroid attachment possibly through downregulating the expression of endometrial estrogen receptor ß and integrin ß3, but not mucin 1. These results were confirmed in both overexpression and knockdown experiments and co-culture assay. Mancozeb but not its metabolite ETU reduced spheroid attachment through modulating gene expression profile and decreasing estrogen receptor ß and integrin ß3 expression of endometrial epithelial cells.


Assuntos
Adesão Celular/efeitos dos fármacos , Endométrio/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Receptor beta de Estrogênio/metabolismo , Fungicidas Industriais/toxicidade , Integrina beta3/metabolismo , Maneb/toxicidade , Esferoides Celulares/efeitos dos fármacos , Zineb/toxicidade , Blastocisto/citologia , Blastocisto/efeitos dos fármacos , Blastocisto/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Cocultura , Regulação para Baixo , Endométrio/citologia , Endométrio/metabolismo , Células Epiteliais/metabolismo , Receptor beta de Estrogênio/genética , Feminino , Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Integrina beta3/genética , Gravidez , Esferoides Celulares/metabolismo
12.
Ecotoxicol Environ Saf ; 208: 111587, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396110

RESUMO

Metalaxyl and Metalaxyl-M are the fungicides that widely used in many countries. In this study, the environmental behaviors between metalaxyl and metalaxyl-M in Tubifex tubifex (T. tubifex) were quantitative analyzed by using a high performance liquid chromatography with photo-diode-array-detector (HPLC-DAD). Results demonstrated that there was no significant difference (p > 0.05) in the concentration of metalaxyl and metalaxyl-M in T. tubifex during the exposure process. However, the dissipation behaviors of metalaxyl and metalaxyl-M in T. tubifex were different (p < 0.05) during the non-exposure culture process. Meanwhile, the toxic effects were also evaluated by comparing the different influences of these two compounds on related physiological indicators, and functional enzyme activities. The survival rates of T. tubifex were 63.33 ± 15.28% (20 mg L-1), 63.33 ± 5.77% (200 mg L-1) treated with metalaxyl and were 50.00 ± 10.00% (20 mg L-1), 46.67 ± 11.55 (200 mg L-1) treated with metalaxyl-M at the non-exposure culture process. The autotomy rates were increased significantly compared with the initial in all treatments. Besides, the activities of CAT, SOD, and GST in T. tubifex were also inhibited by metalaxyl and metalaxyl-M treatments. Finally, the high-throughput transcriptome sequencing technology was applied to investigate the metabolic pathways of target analytes in T. tubifex, and results proved that the metabolic pathways associated with human diseases (such as viral myocarditis) were up-regulated expression for metalaxyl and metalaxyl-M treatments, and metalaxyl-M up-regulated more significantly. All the results demonstrated that metalaxyl-M had a higher toxicity than metalaxyl on T. tubifex.


Assuntos
Alanina/análogos & derivados , Fungicidas Industriais/toxicidade , Oligoquetos/fisiologia , Alanina/toxicidade , Animais , Cromatografia Líquida de Alta Pressão , Oligoquetos/efeitos dos fármacos
13.
Ecotoxicol Environ Saf ; 211: 111920, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33497861

RESUMO

Azoxystrobin is a broad-spectrum strobilurin fungicide for use on a wide range of crops available to end-users as formulated products. Due to its extensive application, it has been detected in aquatic ecosystems, raising concerns about its environmental impact, which is still poorly explored. The objective of this work was to study the effects of a commercial formulation of azoxystrobin in the zebrafish embryo model. Sublethal and lethal effects were monitored during the exposure period from 2 h post fertilisation (hpf) to 96 hpf after exposure to azoxystrobin concentrations (1, 10 and 100 µg L-1). The responses of antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR)) as well as detoxifying enzymes (glutathione-s-transferase (GST) and carboxylesterase (CarE)) were evaluated at 96 hpf. Similarly, glutathione levels (reduced (GSH) and oxidised (GSSG) glutathione), neurotransmission (acetylcholinesterase (AChE)) and anaerobic respiration (lactate dehydrogenase (LDH)) -related enzymes were assayed. At 120 hpf, larvae from each group were used for behaviour analysis. Results from this study showed concentration-dependent teratogenic effects, particularly by increasing the number of malformations (yolk and eye), with a higher prevalence at the highest concentration. However, it was found that the lowest concentration induced a high generation of reactive oxygen species (ROS) and increased activity of SOD, GST, and CarE. In addition, GR and GSSG levels were decreased by the lowest concentration, suggesting an adaptive response to oxidative stress, which is also supported by the increased AChE activity and absence of behavioural changes. These findings advance the knowledge of the azoxystrobin developmental and environmental impacts, which may impose ecotoxicological risks to non-target species.


Assuntos
Embrião não Mamífero/efeitos dos fármacos , Fungicidas Industriais/toxicidade , Pirimidinas/toxicidade , Estrobilurinas/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/embriologia , Animais , Antioxidantes/farmacologia , Catalase/metabolismo , Ecossistema , Embrião não Mamífero/fisiologia , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glutationa Transferase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio , Estrobilurinas/farmacologia , Superóxido Dismutase/metabolismo , Peixe-Zebra/metabolismo
14.
Ecotoxicol Environ Saf ; 211: 111894, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33472108

RESUMO

Enantiomers of chiral fungicides usually display different toxic effects on nontarget organisms in the surrounding environment, although there are rare reports on the enantioselective toxicity of metconazole (MEZ) to aquatic organisms, such as Microcystis flos-aquae (M. flos-aquae). To explore the enantioselective toxicity of MEZ in algae, the impact of various concentrations (0.001, 0.003, 0.01, 0.03 and 0.1 mg/L) of MEZ on M. flos-aquae over 8 days was investigated. Significant differences were observed between the four enantiomers in chlorophyll a (Chl a) contents, carotenoids, photochemical efficiency (Fv/Fm), rapid light-response curves (RLCs), utilization efficiency of light energy (α) and protein contents during treatment time. MEZ can enantioselectively stimulate the chlorophyll fluorescence parameters (RLCs, Fv/Fm and α) and carotenoid and Chl a contents of M. flos-aquae, especially at low concentrations (0.001 or 0.003 mg/L). At high concentrations of 0.03 or 0.1 mg/L, the chlorophyll fluorescence parameters (RLCs, Fv/Fm and α), protein and Chl a contents of M. flos-aquae exposed to cis-enantiomers were lower than those of M. flos-aquae exposed to trans-enantiomers. These observations indicated that the enantiomers of MEZ pose different toxicities to M. flos-aquae, with the cis-enantiomers more toxic than the trans-enantiomers. These results are beneficial for understanding the enantioselective effects of MEZ enantiomers on nontarget organisms and helpful for evaluating their eco-environment risk.


Assuntos
Fungicidas Industriais/toxicidade , Microcystis/fisiologia , Fotossíntese/efeitos dos fármacos , Triazóis/toxicidade , Clorofila A , Microcystis/efeitos dos fármacos , Estereoisomerismo
15.
Sci Total Environ ; 766: 144426, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33421785

RESUMO

The broad application of strobilurin fungicide led to pathogen resistance, and toxic effects have been reported for several species. Benzene kresoxim-methyl (BKM) is a novel strobilurin fungicide mainly used to control the cucumber powdery mildew. However, information about the fate of BKM in agrofood systems and related human exposure is limited. In this study, greenhouse experiments were conducted to investigate the distribution, translocation, and residual of the 10% suspension concentrate (SC) commercial BKM formulations on mature cucumber plants using 14C tracer technology. After foliage and fruit application, 25.84% of the applied 14C-labeled BKM can be absorbed into mature cucumber plants at 21 days after treatment. The absorbed BKM transferred throughout the plant acropetally and basipetally, although over 81.13% of absorbed BKM remained in the labeled leaves. In the edible parts, 14.35% of the absorbed BKM remained in the pericarp of labeled fruits, only 0.027 mg kg-1 accumulated in the sarcocarp. The concentration of BKM in newborn fruits was 0.005 mg kg-1, indicating low dietary exposure. These findings develop a better understanding of the fate of BKM in the cucumber plants, provide guidance in the rational use of BKM and can be incorporated into food and environmental assessments of BKM.


Assuntos
Cucumis sativus , Fungicidas Industriais , Benzeno , Fungicidas Industriais/toxicidade , Humanos , Recém-Nascido , Estrobilurinas
16.
Environ Pollut ; 271: 116292, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33388683

RESUMO

Drilled seeds are an important food resource for many farmland birds but may pose a serious risk when treated with pesticides. Most compounds currently used as seed treatment in the EU have low acute toxicity but may still affect birds in a sub-chronic or chronic way, especially considering that the sowing season lasts several weeks or months, resulting in a long exposure period for birds. Tebuconazole is a triazole fungicide widely used in agriculture but its toxicity to birds remains largely unknown. Our aim was to test if a realistic scenario of exposure to tebuconazole treated seeds affected the survival and subsequent reproduction of the red-legged partridge (Alectoris rufa). We fed captive partridges with wheat seeds treated with 0%, 20% or 100% of tebuconazole application rate during 25 days in late winter (i.e. tebuconazole dietary doses were approximately 0.2 and 1.1 mg/kg bw/day). We studied treatment effects on the physiology (i.e. body weight, biochemistry, immunology, oxidative stress, coloration) and reproduction of partridges. Exposed birds did not reduce food consumption but presented reduced plasmatic concentrations of lipids (triglycerides at both exposure doses, cholesterol at high dose) and proteins (high dose). The coloration of the eye ring was also reduced in the low dose group. Exposure ended 60 days before the first egg was laid, but still affected reproductive output: hatching rate was reduced by 23% and brood size was 1.5 times smaller in the high dose group compared with controls. No significant reproductive effects were found in the low dose group. Our results point to the need to study the potential endocrine disruption mechanism of this fungicide with lagged effects on reproduction. Risk assessments for tebuconazole use as seed treatment should be revised in light of these reported effects on bird reproduction.


Assuntos
Fungicidas Industriais , Melhoramento Vegetal , Animais , Fungicidas Industriais/toxicidade , Reprodução , Sementes , Triazóis/toxicidade
17.
Ecotoxicol Environ Saf ; 209: 111848, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33421672

RESUMO

Fungicides pose a risk for crustacean leaf shredders serving as key-stone species for leaf litter breakdown in detritus-based stream ecosystems. However, little is known about the impact of strobilurin fungicides on shredders, even though they are presumed to be the most hazardous fungicide class for aquafauna. Therefore, we assessed the impact of the strobilurin azoxystrobin (AZO) on the survival, energy processing (leaf consumption and feces production), somatic growth (growth rate and molting activity), and energy reserves (neutral lipid fatty and amino acids) of the amphipod crustacean Gammarus fossarum via waterborne exposure and food quality-mediated (through the impact of leaf colonizing aquatic microorganisms) and thus indirect effects using 2 × 2-factorial experiments over 24 days. In a first bioassay with 30 µg AZO/L, waterborne exposure substantially reduced survival, energy processing and affected molting activity of gammarids, while no effects were observed via the dietary pathway. Furthermore, a negative growth rate (indicating a body mass loss in gammarids) was induced by waterborne exposure, which cannot be explained by a loss in neutral lipid fatty and amino acids. These energy reserves were increased indicating a disruption of the energy metabolism in G. fossarum caused by AZO. Contrary to the first bioassay, no waterborne AZO effects were observed during a second experiment with 15 µg AZO/L. However, an altered energy processing was determined in gammarids fed with leaves microbially colonized in the presence of AZO, which was probably caused by fungicide-induced effects on the microbial decomposition efficiency ultimately resulting in a lower food quality. The results of the present study show that diet-related strobilurin effects can occur at concentrations below those inducing waterborne toxicity. However, the latter seems to be more relevant at higher fungicide concentrations.


Assuntos
Anfípodes/fisiologia , Fungicidas Industriais/toxicidade , Estrobilurinas/toxicidade , Poluentes Químicos da Água/toxicidade , Anfípodes/efeitos dos fármacos , Animais , Dieta , Ecossistema , Folhas de Planta/metabolismo , Pirimidinas , Rios , Testes de Toxicidade Crônica
18.
Chemosphere ; 262: 127793, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32799142

RESUMO

Currently, few studies have investigated the joint toxicity mechanism of azole fungicides at different exposure times and mixed at the relevant environmental concentrations. In this study, three common azole fungicides, namely, myclobutanil (MYC), propiconazole (PRO), and tebuconazole (TCZ), were used in studying the toxic mechanisms of a single substance and its ternary mixture exposed to ambient concentrations of Chlorella pyrenoidosa. Superoxide dismutase (SOD), catalase (CAT), chlorophyll a (Chla), and total protein (TP), were used as physiological indexes. Results showed that three azole fungicides and ternary mixture presented obvious time-dependent toxicities at high concentrations. MYC induced a hormetic effect on algal growth, whereas PRO and TCZ inhibit algal growth in the entire range of the tested concentrations. The toxicities of the three azole fungicides at 7 days followed the order PRO > TCZ > MYC. Three azole fungicides and their ternary mixture induced different levels of SOD and CAT activities in algae at high concentrations. The ternary mixture showed additive effects after 4 and 7 days exposure, but no effect was observed at actual environmental concentrations. The toxic mechanisms may be related to the continuous accumulation of reactive oxygen species, which not only affected protein structures and compositions but also damaged thylakoid membranes, hindered the synthesis of proteins and chlorophyll a, and eventually inhibited algal growth. These findings increase the understanding of the ecotoxicity of azole fungicides and use of azole fungicides in agricultural production.


Assuntos
Antioxidantes/metabolismo , Azóis/toxicidade , Chlorella/efeitos dos fármacos , Fungicidas Industriais/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Catalase/metabolismo , Chlorella/enzimologia , Chlorella/crescimento & desenvolvimento , Clorofila A/metabolismo , Relação Dose-Resposta a Droga , Nitrilos/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Triazóis/toxicidade
19.
Chemosphere ; 262: 127792, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32805656

RESUMO

Tebuconazole is a triazole fungicide, used in agriculture to treat phytopathogenic fungi, and as a biocide, has been reported to be related to reproductive and developmental toxicity. The purpose of this study was to investigate the effect of tebuconazole exposure on rat fetal Leydig cells and fetal testis during pregnancy. Pregnant Sprague-Dawley rats were randomly divided into 4 groups, daily gavaged with corn oil (as a control), 25, 50, and 100 mg/kg body weight tebuconazole for 10 days (from the 12th day of pregnancy). Tebuconazole increased fetal serum testosterone and progesterone levels at a dose of 100 mg/kg. Exposure to 100 mg/kg tebuconazole significantly caused an increase in the number of fetal Leydig cells per testis without inducing cell aggregation. Tebuconazole up-regulated the expression of Star, Cyp11a1, Hsd17b3, and Fshr and their proteins. Further investigation found that tebuconazole caused increased phosphorylation of AKT1, ERK1/2, and mTOR, the level of BCL2, as well as the decrease of Beclin1, LC3B, and BAX, which may contribute to the fetal Leydig cell autophagy and proliferation. In conclusion, in utero exposure of tebuconazole causes the proliferation of fetal Leydig cells.


Assuntos
Fungicidas Industriais/toxicidade , Células Intersticiais do Testículo/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Reprodução/efeitos dos fármacos , Triazóis/toxicidade , Animais , Feminino , Células Intersticiais do Testículo/metabolismo , Masculino , Fosfoproteínas/genética , Fosforilação , Gravidez , Efeitos Tardios da Exposição Pré-Natal/patologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Testículo/efeitos dos fármacos , Testículo/embriologia , Testículo/patologia , Testosterona/sangue , Regulação para Cima
20.
Sci Total Environ ; 754: 142098, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32911151

RESUMO

Despite the high usage of pesticides in current agricultural practices, its effects to humans and to the environment (non-target species) are a continuous concern. Soil dwelling organisms are among the first in line of exposure to pesticides, however their risks are often based on the pure active ingredient (a.i.) and not on the commercial formulated products (FPs) actually applied in the fields. In the present study, we investigated the effects of two fungicide FPs versus its a.i. (s): Amistar® XTRA and the respective a.i. (s) azoxystrobin and cyproconazole, and Prosaro® 250 EC and the respective a.i. (s) prothioconazole and tebuconazole, to the non-target soil oligochaete Enchytraeus crypticus. The standard Enchytraeid Reproduction Test was used to assess effects on survival and reproduction. Results showed that Amistar was more toxic than Prosaro, particularly for reproduction (EC50 = 161 mg Amistar/kg soil, EC50 = 350 mg Prosaro/kg soil). For both FPs, reproductive effects were mainly related to one of its a.i. (s) (azoxystrobin [EC50 = 37 mg azosxystrobin/kg soil] for Amistar, and tebuconazole [EC50 = 41 mg tebuconazole/kg soil] for Prosaro), while lethal effects were not predicted by the toxicity of its a.i. (s) (particularly in the case of Prosaro, which was more toxic than its a.i. (s)). These findings highlight the need to further explore the toxicity data of the FPs compared to the a.i. (s), aiming to predict a more realistic environmental hazard of pesticides.


Assuntos
Fungicidas Industriais , Oligoquetos , Poluentes do Solo , Animais , Fungicidas Industriais/análise , Fungicidas Industriais/toxicidade , Pirimidinas , Reprodução , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Estrobilurinas , Triazóis
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