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1.
Pestic Biochem Physiol ; 202: 105920, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38879321

RESUMO

The queen is the sole reproductive individual and the maturing brood replenishes the shorter-lived worker bees. Production of many crops relies on both pesticides and bee pollination to improve crop quantity and quality. Despite the certain knowledge on chemical pesticides caused damage to worker bee physiology and behavior, our understanding of the relationship between honeybee queen development and chemical pesticides remains weak. Here, we comprehensive investigate the effects of the widely used insecticide chlorantraniliprole on the growth, hormone levels, and detoxifying enzyme activity of queen larvae. It has been determined that chlorantraniliprole present a chronic toxic effect on queen larvae and also reduced the fitness of queen, and that these effects are positively correlated with pesticide levels. It has been found that queen larvae began to show reduced capping and emergence rates when exposed to 2 ng/larva of chlorantraniliprole. At 20 ng/larva, queen capping and emergence rates were the lowest, and there were significant reductions in larval hormone level. Chlorantraniliprole have an effect on detoxification enzyme activity and hormone levels in queen larvae. In conclusion, chlorantraniliprole can adversely affect the growth and development of queen larvae. Our findings may guide the scientifically sound use of chemical pesticides to reduce potential risks to queen larvae.


Assuntos
Inseticidas , Larva , ortoaminobenzoatos , Animais , ortoaminobenzoatos/toxicidade , Larva/efeitos dos fármacos , Inseticidas/toxicidade , Abelhas/efeitos dos fármacos , Abelhas/crescimento & desenvolvimento , Feminino
2.
J Environ Manage ; 145: 210-29, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25058869

RESUMO

Stillage is the main wastewater from ethanol production, generated specifically in the step of distillation. Regardless the feedstock, stillage contains high concentrations of organic matter, potassium and sulfates, as well as acidic and corrosive characteristics. Currently almost the entire volume of stillage generated in Brazilian distilleries is directed to the fertigation of sugarcane fields, due to its fertilizer character. However, the polluting potential of stillage characterizes its land disposal as problematic, considering probable negative impacts on the soil structure and water resources in case of excessive dosages. Since the literature lacks critical content describing clearly the cons related to the reuse of stillage in agriculture in the long-term, this review aimed to assess the real polluting potential of stillage, and the implications of its land disposal and/or discharge into water bodies. Evidence from the literature indicate that the main obstacles to reuse stillage in natura include risks of soil salinization; clogging of pores, reduction in the microbial activity and the significant depletion of dissolved oxygen concentrations in water bodies; contamination per nitrates and eutrophication; soil structure destabilization due to high concentrations of potassium and sodium; and, possible acidification of soil and water resources, considering the low pH of stillage (∼4,5). Toxic metals, such as cadmium, lead, copper, chromium and nickel, were also identified in concentrations above the recommended limits in stillage samples, increasing risks to human health (e.g. carcinogenic potential) and to crops (e.g. productivity loss). In short, although some studies report benefits from the land application of stillage, its treatment prior to disposal is essential to make fertigation an environmentally suitable practice.


Assuntos
Fertilizantes/análise , Solo/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Brasil , Produtos Agrícolas , Destilação
3.
Mar Pollut Bull ; 199: 115978, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38217911

RESUMO

The detrimental effects of anthropogenic underwater noise on marine organisms have garnered significant attention among scientists. This review delves into the research concerning the repercussions of underwater noise on marine species, with specific emphasis on the physiological and molecular responses of marine biota. This review investigates the sensory mechanisms, hearing sensitivity, and reaction thresholds of diverse marine organisms, shedding light on their susceptibility to underwater noise disturbances. The physiological and molecular effects of anthropogenic underwater noise on marine biota include oxidative stress, energy homeostasis, metabolism, immune function, and respiration. Additionally, changes in the gene expression profile associated with oxidative stress, metabolism, and immunological response are among the responses reported for marine biota. These effects pose a threat to animal fitness and potentially affect their survival as individuals and populations.


Assuntos
Organismos Aquáticos , Ruído , Humanos , Animais , Organismos Aquáticos/fisiologia , Audição/fisiologia , Biota
4.
NanoImpact ; 29: 100450, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36610661

RESUMO

The terrestrial environment is one of the main recipients of plastic waste. However, limited research has been performed on soil contamination by plastics and even less assessing the effects of nanoplastics (NPls). Behind the potential toxicity caused per se, NPls are recognized vectors of other environmental harmful contaminants. Therefore, the main aim of the present study is to understand whether the toxicity of an industrial chemical (bisphenol A - BPA) and a pharmaceutical (diphenhydramine - DPH) changes in the presence of polystyrene NPls to the terrestrial invertebrate Folsomia candida. Assessed endpoints encompassed organismal (reproduction, survival and behavior) and biochemical (neurotransmission and oxidative stress) levels. BPA or DPH, 28 d single exposures (1 to 2000 mg/kg), induce no effect on organisms' survival. In terms of reproduction, the calculated EC50 (concentration that causes 50% of the effect) and determined LOEC (lowest observed effect concentration) were higher than the environmental concentrations, showing that BPA or DPH single exposure may pose no threat to the terrestrial invertebrates. Survival and reproduction effects of BPA or DPH were independent on the presence of NPls. However, for avoidance behavior (48 h exposure), the effects of the tested mixtures (BPA + NPls and DPH + NPls) were dependent on the NPls concentration (at 0.015 mg/kg - interaction: no avoidance; at 600 mg/kg - no interaction: avoidance). Glutathione S-transferase activity increased after 28 d exposure to 100 mg/kg DPH + 0.015 mg/kg NPls (synergism). The increase of lipid peroxidation levels found after the exposure to 0.015 mg/kg NPls (a predicted environmental concentration) was not detected in the mixtures (antagonism). The results showed that the effects of the binary mixtures were dependent on the assessed endpoint and the tested concentrations. The findings of the present study show the ability of NPls to alter the effects of compounds with different natures and mechanisms of toxicity towards soil organisms, showing the importance of environmental risk assessment considering mixtures of contaminants.


Assuntos
Artrópodes , Difenidramina , Animais , Difenidramina/farmacologia , Microplásticos/farmacologia , Solo , Invertebrados
5.
PeerJ ; 11: e16024, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37846312

RESUMO

Management of deep-sea fisheries in areas beyond national jurisdiction by Regional Fisheries Management Organizations/Arrangements (RFMO/As) requires identification of areas with Vulnerable Marine Ecosystems (VMEs). Currently, fisheries data, including trawl and longline bycatch data, are used by many RFMO/As to inform the identification of VMEs. However, the collection of such data creates impacts and there is a need to collect non-invasive data for VME identification and monitoring purposes. Imagery data from scientific surveys satisfies this requirement, but there currently is no established framework for identifying VMEs from images. Thus, the goal of this study was to bring together a large international team to determine current VME assessment protocols and establish preliminary global consensus guidelines for identifying VMEs from images. An initial assessment showed a lack of consistency among RFMO/A regions regarding what is considered a VME indicator taxon, and hence variability in how VMEs might be defined. In certain cases, experts agreed that a VME could be identified from a single image, most often in areas of scleractinian reefs, dense octocoral gardens, multiple VME species' co-occurrence, and chemosynthetic ecosystems. A decision flow chart is presented that gives practical interpretation of the FAO criteria for single images. To further evaluate steps of the flow chart related to density, data were compiled to assess whether scientists perceived similar density thresholds across regions. The range of observed densities and the density values considered to be VMEs varied considerably by taxon, but in many cases, there was a statistical difference in what experts considered to be a VME compared to images not considered a VME. Further work is required to develop an areal extent index, to include a measure of confidence, and to increase our understanding of what levels of density and diversity correspond to key ecosystem functions for VME indicator taxa. Based on our results, the following recommendations are made: 1. There is a need to establish a global consensus on which taxa are VME indicators. 2. RFMO/As should consider adopting guidelines that use imagery surveys as an alternative (or complement) to using bycatch and trawl surveys for designating VMEs. 3. Imagery surveys should also be included in Impact Assessments. And 4. All industries that impact the seafloor, not just fisheries, should use imagery surveys to detect and identify VMEs.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Conservação dos Recursos Naturais/métodos , Pesqueiros
6.
Pest Manag Sci ; 78(4): 1407-1416, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34897947

RESUMO

BACKGROUND: Declines in bee populations and diversity have drawn international attention. The long-term use of chemical pesticides has affected bee behavior and physiology. This study aimed to investigate the effects of chronic exposure to four commonly used chemical pesticides (beta-cypermethrin, chlorbenzuron, chlorothalonil and pendimethalin) on the growth of Apis mellifera ligustica and Apis cerana cerana larvae reared in vitro. RESULTS: Pesticide type and concentration were the main factors affecting honeybee fitness. Beta-cypermethrin and chlorbenzuron had chronic toxic effects on bee larvae. They reduced the fitness of A. m. ligustica and A. c. cerana even at low doses of 323.5 ng g-1 for beta-cypermethrin and 62.6 ng g-1 for chlorbenzuron in bee bread. The effects were positively associated with the dietary amounts of pesticides. By contrast, chlorothalonil and pendimethalin exposure did not affect bee larvae despite changes in enzyme activities. Caution is still needed with chlorothalonil, which led to a decrease in harvest adult bee numbers at a high dose (6937.2 ng g-1 ). Furthermore, a difference in pesticide resistance was observed, suggesting that A. m. ligustica may tolerate toxic effects better than A. c. cerana. CONCLUSION: This study sheds new light on chronic toxicity in bee larvae exposed to residues in bee bread. The results could guide the scientific and rational use of chemical pesticides to reduce the potential risks to A. m. ligustica and A. c. cerana. © 2021 Society of Chemical Industry.


Assuntos
Larva , Compostos de Anilina , Animais , Abelhas , Imidas , Nitrilas , Compostos de Fenilureia , Piretrinas
7.
Insects ; 12(10)2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34680667

RESUMO

The decreasing number of bees is a global ecological problem. With the advancement of agricultural modernisation, the large-scale use of neonicotinoid insecticides is one of the main factors leading to the decline of bees. The aim of the present study was to investigate the effect and the mechanisms underlying bees impaired by dinotefuran. Acute (48 h) oral toxicity tests showed that a 5% lethal concentration (LC5) was 0.220 mg/L, and a 20% lethal concentration (LC20) was 0.458 mg/L. The gene expression profile shows that when compared with the control group, the LC5 group induced 206 significantly upregulated, differentially expressed genes (DEGs) and 363 significantly downregulated DEGs, while the LC20 group induced 180 significantly upregulated DEGs and 419 significantly downregulated DEGs. Significantly, transcriptomic analysis revealed DEGs involved in immunity, detoxification, and the nervous system, such as antimicrobial peptides, vitellogenin, synaptotagmin-10, AChE-2, and nAChRa9. Furthermore, Gene Ontology (GO) annotation and Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway analysis revealed that DEGs were enriched in amino acid and fatty acid biosynthesis and metabolism pathways. Collectively, our findings will help clarify the deleterious physiological and behavioural impacts of dinotefuran on bees and provide a basis for future research on the mechanisms underlying bees impaired by dinotefuran.

8.
Sci Total Environ ; 744: 140819, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-32693280

RESUMO

Understanding the causes of the decline in bee population has attracted intensive attention worldwide. The indiscriminate use of agrochemicals is a persistent problem due to their physiological and behavioural damage to bees. Glyphosate and its commercial formulation stand out due to their wide use in agricultural areas and non-crop areas, such as parks, railroads, roadsides, industrial sites, and recreational and residential areas, but the mode of action of glyphosate on bees at the molecular level remains largely unelucidated. Here, we found that the numbers of differentially expressed genes and metabolites under glyphosate commercial formulation (GCF) stress were significantly higher in Apis cerana cerana than in Apis mellifera ligustica. Despite these differences, the number of differentially expressed transcripts increased following an increase in the GCF treatment time in both A. cerana cerana and A. mellifera ligustica. GCF exerted adverse impacts on the immune system, digestive system, nervous system, amino acid metabolism, carbohydrate metabolism, growth and development of both bee species by influencing their key genes and metabolites to some extent. The expression of many genes involved in immunity, agrochemical detoxification and resistance, such as antimicrobial peptides, cuticle proteins and cytochrome P450 families, was upregulated by GCF in both bee species. Collectively, our results indicate that both A. cerana cerana and A. mellifera ligustica strive to mitigate the pernicious effects caused by GCF by regulating detoxification and immune systems. Moreover, A. cerana cerana might be better able to withstand the toxic effects of GCF with lower fitness costs than A. mellifera ligustica. Our work will contribute to elucidating the deleterious physiological and behavioural impacts of GCF on bees.


Assuntos
Metabolômica , Transcriptoma , Animais , Abelhas , Glicina/análogos & derivados , Glifosato
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