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1.
Carbohydr Polym ; 259: 117749, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33673979

RESUMO

The increasing world-wide demand for food has prompted the development of efficient and environmentally friendly pesticide formulations. In this article, we have prepared CMC-g-PRSG carrier based on two compounds from natural materials carboxymethyl cellulose (CMC) and rosin (RS). The model pesticide avermectin (AVM) was encapsulated through hydrophobic interaction, and self-assembled to form nanopesticide AVM@CMC-g-PRSG with an average particle size of 167 nm. The prepared nanopesticide displays enhanced dispersibility and stability of AVM in water, and can effectively adhere to the leaves to prevent loss. The release rate of AVM encapsulated in the nanocarrier can be controlled by adjusting pH, and AVM half-life under ultraviolet radiation shows a 3-fold increase allowing control of pests for prolonged periods of time in practical applications. Biological safety tests showed that AVM@CMC-g-PRSG effectively reduces the toxicity of AVM to aquatic animals. Therefore, the cheap and degradable carrier CMC-g-PRSG can improve the effect of hydrophobic pesticides.


Assuntos
Carboximetilcelulose Sódica/química , Portadores de Fármacos/química , Resinas Vegetais/química , Animais , Liberação Controlada de Fármacos , Meia-Vida , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Ivermectina/análogos & derivados , Ivermectina/química , Ivermectina/metabolismo , Ivermectina/farmacologia , Larva/efeitos dos fármacos , Nanopartículas/química , Tamanho da Partícula , Controle de Pragas/métodos , Praguicidas/química , Praguicidas/metabolismo , Praguicidas/farmacologia , Raios Ultravioleta , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/fisiologia
2.
J Environ Pathol Toxicol Oncol ; 40(1): 43-50, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33639072

RESUMO

Exposure to organochlorine pesticides (OCPs) may be a risk factor for breast cancer (BC). Their role may be more relevant in developing countries such as India, where an abundance of these products is used for agricultural purposes. The present study compares OCP tissue levels in patients who underwent BC surgery (group A) or patients who had surgery for excision of breast fibroadenoma (group B). We perform OCP level quantification using a PerkinElmer, Inc. (Waltham, MA) gas chromatograph (GC) that is equipped with a 63Ni selective electron-capture detector. Significantly higher breast tissue OCP levels are present in the study population, indicating significant exposure. We detect 18 different types of OPCs in study subjects, with six OPCs (γ-hexachlorocyclohexane [HCH], δ-HCH, endrin, endosulfan-II, p,p'-dichlorodiphenyldichloroenthane [DDD], and p,p'-dichlorodiphenyltrichloroenthane [DDT]) present in all subjects. Endosulfan-II, p,p'-DDT, and p,p'-DDD tissue levels are significantly higher in BC patients than in those with fibroadenoma. Higher tissue levels of OCPs (α-HCH) are significantly associated with the presence of extracapsular spread (1.42 vs. 0.91; p = 0.04) and higher disease stage (early BC vs. locally advanced BC; 18.90 vs. 11.90; p = 0.04). The present pilot study indicates higher OCP tissue levels in northern India BC patients compared to patients with fibroadenoma.


Assuntos
Neoplasias da Mama/metabolismo , Fibroadenoma/metabolismo , Hidrocarbonetos Clorados/metabolismo , Praguicidas/metabolismo , Adulto , Feminino , Humanos , Índia , Pessoa de Meia-Idade , Projetos Piloto
3.
Food Chem ; 346: 128894, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33422918

RESUMO

This study was undertaken to assess the potential of Tribolium castaneum (Red flour beetle) acetylcholinesterase (Tc-AChE) based electrochemical biosensor integrating WO3/g-C3N4 nanocomposite modified Pencil graphite electrode to detect an organophosphate insecticide, Phosmet. The WO3/g-C3N4 nanocomposite provides a non-toxic, biocompatible surface for binding the enzyme on the electrode surface, attributed to its large surface area, high conductivity, and low ohmic resistance. The proposed biosensor shows a very good analytical performance with LOD 3.6 nM for Phosmet and effectively determined Phosmet in wheat with a 99% recovery rate. Furthermore, molecular docking deciphers the binding interactions of Phosmet with Tc-AChE using a modified AutoDock LGA algorithm and an AMBER03 force field in YASARA. The kinetic parameters strongly suggest the high potency of inhibitor with the enzyme. This study presents an adaptable, rapid, and straightforward approach that opens ways towards real progress in developing commercial biosensors for pesticide detection.


Assuntos
Acetilcolinesterase/metabolismo , Técnicas Biossensoriais/instrumentação , Grão Comestível/química , Grafite/química , Nitrilos/química , Óxidos/química , Fosmet/análise , Tungstênio/química , Animais , Besouros/enzimologia , Eletrodos , Armazenamento de Alimentos , Simulação de Acoplamento Molecular , Nanocompostos/química , Praguicidas/análise , Praguicidas/metabolismo , Fosmet/metabolismo
4.
Ecotoxicol Environ Saf ; 208: 111654, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396168

RESUMO

Salicylic acid (SA) is an important signal molecule, regulating oxidative stress response in plants. In this study, we evaluated the influences of SA (1 mg L-1, 10 mg L-1 and 50 mg L-1) on the accumulation of clothianidin (CLO), dinotefuran (DFN) and difenoconazole (DFZ) (5 mg L-1) and pesticide-induced (CLO-10 mg L-1, DFN-20 mg L-1, and DFZ-10 mg L-1) oxidative stress in cucumber plants. Exogenous SA at 10 mg L-1 significantly reduced the half-lives of three pesticides in nutrient solution and prevented the accumulation of pesticides in roots and leaves. And the role of SA in reducing residues was related to the major accumulation sites of pesticides. By calculating the root concentration factor (RCF) and translocation factor (TF), we found that SA at 10 mg L-1 reduced the ability of roots to absorb pesticides and enhanced the translocation ability from roots to leaves. Roots exposed to high concentrations of three pesticides could reduce biomass, low chlorophyll content, increase the accumulation of reactive oxygen species (ROS) and proline, promote lipid peroxidation, and alter the activities of a range of antioxidant enzymes, respectively. Exogenous SA at low concentrations (1 mg L-1 and 10 mg L-1) significantly mitigated these negative effects. Hence, application of exogenous SA at 10 mg L-1 could effectively alleviate the accumulation of pesticides and induce stress tolerance in cucumber planting systems.


Assuntos
Cucumis sativus/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Praguicidas/metabolismo , Ácido Salicílico/farmacologia , Antioxidantes/metabolismo , Clorofila/metabolismo , Cucumis sativus/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Praguicidas/toxicidade , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Prolina/metabolismo , Espécies Reativas de Oxigênio/metabolismo
5.
Food Chem ; 339: 127985, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920305

RESUMO

There is limited research focusing on the effects of human gut microbiota on the oral bioaccessibility and intestinal absorption of pesticide residues in food. In the present study, we use a modified setup of the Simulator of the Human Intestinal Microbial Ecosystem for the determination of pesticide residue bioaccessibility in Chaenomeles speciosa, and a Caco-2 cell model of human intestinal absorption. Results showed that gut microbiota played a dual role based their effects on contaminant release and metabolism in the bioaccessibility assay, and Lactobacillus plantarum was one of key bacterial species in the gut microbiota that influenced pesticide stability significantly. The addition of L. plantarum to the system reduced the relative amounts (by 11.40-86.51%) of six pesticides. The interaction between the food matrix and human gut microbiota led to different absorption rates, and the barrier effects increased with an increase in incubation time.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Praguicidas/farmacologia , Rosaceae/química , Bactérias/metabolismo , Células CACO-2 , Humanos , Mucosa Intestinal/citologia , Mucosa Intestinal/microbiologia , Lactobacillus plantarum/efeitos dos fármacos , Lactobacillus plantarum/isolamento & purificação , Neonicotinoides/metabolismo , Neonicotinoides/farmacologia , Nitrocompostos/metabolismo , Nitrocompostos/farmacologia , Compostos Organotiofosforados/metabolismo , Compostos Organotiofosforados/farmacologia , Praguicidas/química , Praguicidas/metabolismo , Rosaceae/metabolismo , Tiametoxam/metabolismo , Tiametoxam/farmacologia
6.
Chemosphere ; 262: 127848, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32771708

RESUMO

Honey bees are important pollinators and are subject to numerous stressors, such as changing floral resources, parasites, and agrochemical exposure. Pesticide exposure has been linked to the decline in the global honey bee population. We have limited knowledge of the metabolic pathways and synergistic effects of xenobiotics in bees. Quercetin is one of the most abundant phytochemicals in plants and is therefore abundant in the honey bee diet. Quercetin can upregulate the detoxification system in honey bees; however, it is still unknown to what extent quercetin ingestion can reduce the content of absorbed pesticides. In this study, we investigated the effect of dietary quercetin on the contents of three pesticides in honey bees: imidacloprid (insecticide), tebuconazole (fungicide), and tau-fluvalinate (insecticide and acaricide). Bees were divided into two main groups and fed either quercetin-sucrose paste or only sucrose for 72 h. Thereafter, they were orally exposed to ∼10 ng/bee imidacloprid or contact-exposed to ∼0.9 µg/bee tau-fluvalinate or ∼5.2 µg/bee tebuconazole. After 1 h of oral exposure or 24 h of contact exposure, the bees were anaesthetised with CO2, sacrificed by freezing, and extracted with a validated QuEChERS method. Subsequently, the concentrations of the three pesticides and quercetin in the bees were determined with a triple quadrupole tandem mass spectrometer coupled to an HPLC system. No significant effect on the concentration of tebuconazole or tau-fluvalinate was observed in bees fed quercetin. Intake of quercetin led to a reduction in the concentration of imidacloprid in honey bees. Quercetin-rich plants may be exploited in future beekeeping.


Assuntos
Abelhas/metabolismo , Praguicidas/metabolismo , Quercetina , Acaricidas , Animais , Criação de Abelhas , Dieta , Inseticidas , Neonicotinoides , Nitrilos , Nitrocompostos , Compostos Fitoquímicos , Piretrinas , Xenobióticos
7.
Ecotoxicol Environ Saf ; 209: 111861, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33383338

RESUMO

Soybean pod borer (Leguminivora glycinivorella) is an important pest in soybean production, and chemical pesticides was major way for prevention. However, it is difficult to balance the efficiency and safety of pesticide application. In this paper, we evaluated safety and effectiveness of common insecticides (chlorpyrifos and lambda-cyhalothrin) on soybean from three aspects, including distribution, dissipation and control effect, around three major soybean production area (Anhui, Jilin and Shandong) in China. For chlorpyrifos, the initial deposition of each position (upper leaf, lower leaf, upper stem, lower stem, soybean and root) was determinated for 0.23 mg/kg to 70.7 mg/kg, and the half-lifes ranged from 1.96 days to 5.36 days. For lambda-cyhalothrin, the initial deposition of the position was determinated for 0.10 mg/kg to 2.54 mg/kg, and the half-lifes ranged from 2.45 days to 7.26 days. We found that the target insecticides were major deposition and faster degradation in upper stem and leaf. Through comparing the relationship between field control effect and residue, it can be suggested that 40% chlorpyrifos EC and 2.5% lambda-cyhalothrin WE should be sprayed at 600 g a.i./ha and 5.63 g a.i./ha for SPB prevention. This study enhanced our understanding of distribution, dissipation and relationship between residue and control effect. The results provided data support for guiding the precise and scientific application of chemical insecticides on soybean.


Assuntos
Clorpirifos/metabolismo , Inseticidas/metabolismo , Mariposas , Nitrilos/metabolismo , Piretrinas/metabolismo , Soja/metabolismo , Animais , China , Inseticidas/análise , Praguicidas/metabolismo , Folhas de Planta/química
8.
Extremophiles ; 24(6): 897-908, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32968825

RESUMO

A psychrotolerant Sphingobacterium sp. was isolated from the apple orchard situated in the Kufri region of Shimla, Himachal Pradesh, India using an enrichment culture technique having chlorpyrifos (CP) as the sole source of carbon and energy. Based on biochemical characterization and 16S rRNA analysis, the strain was identified as Sphingobacterium sp. C1B. The bacterium C1B was able to degrade chlorpyrifos ≥ 42 ppm and ≥ 36 ppm within 14 days at 20 °C and 15 °C, respectively. The strain was also able to degrade chlorpyrifos ≤ 35 ppm at 28 °C within 14 days. The enzyme organophosphorus hydrolase might be responsible for the initial degradation of CP by the strain C1B. Based on the HPLC and GCMS analysis, a probable degradation pathway has been proposed, which followed the path from chlorpyrifos to 3,5,6-trichloro-2-pyridinol to benzene, 1,3-bis (1,1-dimethylethyl) and then entered into the TCA cycle. Our current study revealed that the bacterium C1B was found to be a useful strain for the degradation of pesticide chlorpyrifos in the cold climatic environment.


Assuntos
Biodegradação Ambiental , Clorpirifos/metabolismo , Malus/microbiologia , Praguicidas/metabolismo , Sphingobacterium/metabolismo , Temperatura Baixa , Índia , RNA Ribossômico 16S , Sphingobacterium/genética
9.
Ecotoxicol Environ Saf ; 202: 110912, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800247

RESUMO

Occupational exposure to pesticides has been identified as a factor that predisposes to disorders of the immune system. Immunosuppression, autoimmunity, cancer of various organs and other diseases in people who apply these products have been reported by the studies. This study aimed to investigate the relationship between occupational exposure to pesticides and the immunological profile in 43 farmers exposed to mixtures of pesticides for at least 15 years. A control group composed of 30 individuals without a history of occupational exposure to pesticides was also evaluated. Peripheral blood samples were processed by flow cytometry and cells were labelled with an 8-color monoclonal antibody panel. Plasma cytokines were also measured. Significant increase in classical monocytes (p < 0.001) and dendritic cells (p < 0.001) in the exposed group was observed as well in total T cells (p = 0.04), central memory CD8 T cells (p = 0.02) and effector memory CD8 T cells (p = 0.01). On the other hand, the activation markers of T cells as the expression of CD57, HLA-DR, CD25 and CD28 were evaluated and no difference was found between groups. When the B cells were analyzed, a significant decrease in total B cells (p = 0.01), regulatory B cells (p < 0.001) and plasmablasts (p < 0.001) in the exposed group, compared to healthy controls, was observed. Pro-inflammatory IL-6 was significantly elevated (p = 0.04) in the plasma of farmers compared to that of controls. The constant antigenic stimulus that occurs during exposure to pesticides can favor the recruitment of dendritic cells and macrophages (APCs) presents in the skin and respiratory tract. In the secondary lymphoid organs, the CD4 T and B cells that process such antigens are possibly undergoing proliferative exhaustion, with the consequent depletion of all mature B subpopulations. The resulting drop in humoral immunity may be offset by an increase in the number of circulating CD8 T lymphocytes due to their cytotoxic action.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Exposição Ocupacional/estatística & dados numéricos , Praguicidas/toxicidade , Adulto , Poluentes Ocupacionais do Ar/análise , Linfócitos B/imunologia , Brasil , Antígenos CD28/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Citocinas/metabolismo , Fazendeiros , Feminino , Citometria de Fluxo , Antígenos HLA-DR/metabolismo , Humanos , Subunidade alfa de Receptor de Interleucina-2 , Masculino , Pessoa de Meia-Idade , Praguicidas/análise , Praguicidas/metabolismo
10.
Ecotoxicology ; 29(9): 1293-1305, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32740705

RESUMO

Biofilms are a consortium of communities of organisms that live in syntrophic relationships and present a higher organization level than that of individual cells. Biofilms dominate microbial life in streams and rivers, enable crucial ecosystem processes, contribute to global biogeochemical flows and represent the main active bacterial life form. Epilithic biofilms are the main biomass found in rivers; their exposure to contaminants can lead to changes in their structure and composition. The composition of these communities is influenced by physicochemical factors, temperature, light and prior exposure to pollutants, among other factors, and it can be used for water quality monitoring purposes. The heterogenous composition of biofilms enables them to accumulate compounds in an integrative manner. Moreover, the availability of several sorption sites and their likely saturation can contribute to bioaccumulation. In aquatic environments, biofilms are also susceptible to the acquisition of antibiotic resistance genes and participate in their dissemination. Anthropic pressure intensification processes continuously expose water resources and, consequently, biofilm communities to different contamination sources. Therefore, the use of biofilms to indicate environmental pollution is reinforced by the progress of studies on the subject. Biofilm communities' response to pollutants in aquatic environments can be mainly influenced by the presence of different organisms, which may change due to community development or age. The current research aims to review studies about biofilm contamination and highlight the importance of biofilm use to better evaluate and maintain the quality of water bodies.


Assuntos
Biofilmes , Praguicidas/metabolismo , Preparações Farmacêuticas/metabolismo , Poluentes Químicos da Água/metabolismo , Biodegradação Ambiental , Ecossistema
11.
Ecotoxicol Environ Saf ; 201: 110852, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32554204

RESUMO

Maps with grey or even white spaces are still present in spite of the fact that persistent organic pollutants (POPs) are at the forefront of research in aquatic toxicology and environmental safety. This is also the case for the Mureș River basin. The intensive use of industrial substances such as polychlorinated biphenyls (PCBs) and pesticides such as organochlorine compounds (OCPs) has caused global contamination of the aquatic environment. In our study we have found very high concentrations of both PCBs (2110-169,000 ng/g lipid weight ΣPCB, 1950-166,000 ng/g lipid weight ΣPCB7) and OCPs (1130-7830 ng/g lipid weight ΣDDT, 47.6-2790 ng/g lipid weight ΣHCH, 5.53-35.6 ng/g lipid weight ΣChlordane, and 6.74-158 ng/g lipid weight HCB) in the gonad tissue of Barbus barbus (Linnaeus, 1758) males and females. Contrary to most studies where the weight, length, and lipid percentage are positively correlated with the concentration of POPs from different tissue types, we observed a downward trend for the lipid normalized concentrations of some pollutants in gonads while these indices were actually increasing. The decrease of lipid normalized POPs with the increase of CF and lipid percentage may be due to the fact that individuals are eliminating hard and soft roes every year during reproduction which could mean that some quantities of pollutants are also eliminated along with the hard and soft roes. The high POPs concentrations found in our study should be a needed wakeup call for environmentalists and a starting point in developing monitoring and management measures for these pollutants.


Assuntos
Bioacumulação , Cyprinidae/metabolismo , Monitoramento Ambiental/métodos , Gônadas/metabolismo , Rios/química , Poluentes Químicos da Água/análise , Animais , Feminino , Hidrocarbonetos Clorados/análise , Hidrocarbonetos Clorados/metabolismo , Masculino , Praguicidas/análise , Praguicidas/metabolismo , Bifenilos Policlorados/análise , Bifenilos Policlorados/metabolismo , Romênia , Poluentes Químicos da Água/metabolismo
12.
Emerg Top Life Sci ; 4(1): 59-76, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32558901

RESUMO

Parasites are linked to the decline of some bee populations; thus, understanding defense mechanisms has important implications for bee health. Recent advances have improved our understanding of factors mediating bee health ranging from molecular to landscape scales, but often as disparate literatures. Here, we bring together these fields and summarize our current understanding of bee defense mechanisms including immunity, immunization, and transgenerational immune priming in social and solitary species. Additionally, the characterization of microbial diversity and function in some bee taxa has shed light on the importance of microbes for bee health, but we lack information that links microbial communities to parasite infection in most bee species. Studies are beginning to identify how bee defense mechanisms are affected by stressors such as poor-quality diets and pesticides, but further research on this topic is needed. We discuss how integrating research on host traits, microbial partners, and nutrition, as well as improving our knowledge base on wild and semi-social bees, will help inform future research, conservation efforts, and management.


Assuntos
Anti-Infecciosos/metabolismo , Abelhas/imunologia , Abelhas/fisiologia , Parasitos/microbiologia , Viroses/imunologia , Animais , Comportamento Animal , Biodiversidade , Dieta , Ecossistema , Interações Hospedeiro-Parasita , Imunidade , Microbiota , Praguicidas/metabolismo
13.
PLoS One ; 15(6): e0234865, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32598366

RESUMO

In this study, we selected and characterized different pesticide-tolerant bacteria isolated from a biomixture of a biopurification system that had received continuous applications of a pesticides mixture. The amplicon analysis of biomixture reported that the phyla Proteobacteria, Firmicutes, Bacteroidetes and Actinobacteria were predominant. Six strains grew in the presence of chlorpyrifos and iprodione. Biochemical characterization showed that all isolates were positive for esterase, acid phosphatase, among others, and they were identified as Pseudomonas, Rhodococcus and Achromobacter based on molecular and proteomic analysis. Bacterial growth decreased as both pesticide concentrations increased from 10 to 100 mg L-1 in liquid culture. The Achromobacter sp. strain C1 showed the best chlorpyrifos removal rate of 0.072-0.147 d-1 a half-life of 4.7-9.7 d and a maximum metabolite concentration of 2.10 mg L-1 at 120 h. On the other hand, Pseudomonas sp. strain C9 showed the highest iprodione removal rate of 0.100-0.193 d-1 a half-life of 4-7 d and maximum metabolite concentration of 0.95 mg L-1 at 48 h. The Achromobacter and Pseudomonas strains showed a good potential as chlorpyrifos and iprodione-degrading bacteria.


Assuntos
Achromobacter/metabolismo , Biodegradação Ambiental , Praguicidas/metabolismo , Pseudomonas/metabolismo , Microbiologia do Solo , Achromobacter/isolamento & purificação , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/metabolismo , Aminoimidazol Carboxamida/toxicidade , Clorpirifos/metabolismo , Clorpirifos/toxicidade , Hidantoínas/metabolismo , Hidantoínas/toxicidade , Praguicidas/toxicidade , Pseudomonas/isolamento & purificação , Poluentes do Solo/metabolismo , Poluentes do Solo/toxicidade , Recursos Hídricos
14.
Chemosphere ; 257: 127165, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32480088

RESUMO

Phytoplankton and bacterioplankton are the key components of the organic matter cycle in aquatic ecosystems, and their interactions can impact the transfer of carbon and ecosystem functioning. The aim of this work was to assess the consequences of chemical contamination on the coupling between phytoplankton and bacterioplankton in two contrasting marine coastal ecosystems: lagoon waters and offshore waters. Bacterial carbon demand was sustained by primary carbon production in the offshore situation, suggesting a tight coupling between both compartments. In contrast, in lagoon waters, due to a higher nutrient and organic matter availability, bacteria could rely on allochthonous carbon sources to sustain their carbon requirements, decreasing so the coupling between both compartments. Exposure to chemical contaminants, pesticides and metal trace elements, resulted in a significant inhibition of the metabolic activities (primary production and bacterial carbon demand) involved in the carbon cycle, especially in offshore waters during spring and fall, inducing a significant decrease of the coupling between primary producers and heterotrophs. This coupling loss was even more evident upon sediment resuspension for both ecosystems due to the important release of nutrients and organic matter. Resulting enrichment alleviated the toxic effects of contaminants as indicated by the stimulation of phytoplankton biomass and carbon production, and modified the composition of the phytoplankton community, impacting so the interactions between phytoplankton and bacterioplankton.


Assuntos
Fitoplâncton/fisiologia , Poluentes Químicos da Água/toxicidade , Bactérias/metabolismo , Biomassa , Carbono/metabolismo , Ecossistema , Praguicidas/metabolismo , Estações do Ano , Água do Mar/química , Oligoelementos/metabolismo
15.
Ecotoxicol Environ Saf ; 200: 110734, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32464440

RESUMO

Microorganisms' role in pesticide degradation has been studied widely. Insitu treatments of effluents containing pesticides such as biological beds (biobeds) are efficient biological systems where biomixture (mixture of substrates) and microorganisms are the keys in pesticide treatment; however, microbial activity has been studied poorly, and its potential beyond biobeds has not been widely explored. In this study, the capacity of microbial consortium and bacteria-pure strains isolated from a biomixture (soil-straw; 1:1, v/v) used to treat agricultural effluents under real conditions were evaluated during a bioremediation process of five pesticides commonly used Yucatan Mexico. Atrazine, carbofuran, and glyphosate had the highest degradations (>90%) using the microbial consortium; 2,4-D and diazinon were the most persistent (DT50 = 8.64 and 6.63 days). From the 21 identified bacteria species in the microbial consortium, Pseudomonas nitroreducens was the most abundant (52%) according to identified sequences. For the pure strains evaluation 2,4-D (DT50 = 9.87 days), carbofuran (DT50 = 8.27 days), diazinon (DT50 = 8.80 days) and glyphosate (DT50 = 8.59 days) were less persistent in the presence of the mixed consortium (Ochrobactrum sp. DGG-1-3, Ochrobactrum sp. Ge-14, Ochrobactrum sp. B18 and Pseudomonas citronellolis strain ADA-23B). Time, pesticide, and strain type were significant (P < 0.05) in pesticide degradation, so this process is multifactorial. Microbial consortium and pure strains can be used to increase the biobed efficiency by inoculation, even in the remediation of soil contaminated by pesticides in agricultural areas.


Assuntos
Bactérias/metabolismo , Consórcios Microbianos , Praguicidas/metabolismo , Poluentes do Solo/metabolismo , Ácido 2,4-Diclorofenoxiacético/metabolismo , Agricultura , Atrazina/metabolismo , Bactérias/isolamento & purificação , Biodegradação Ambiental , Carbofurano/metabolismo , Diazinon/metabolismo , Glicina/análogos & derivados , Glicina/metabolismo , Pseudomonas/isolamento & purificação , Solo/química
16.
Xenobiotica ; 50(11): 1380-1392, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32421406

RESUMO

Pesticides are now recognised to interact with drug transporters, but only few data are available on this issue for carbamate pesticides, a widely used class of agrochemicals, to which humans are highly exposed. The present study was therefore designed to determine whether four representative carbamate pesticides, i.e. the insecticides aminocarb and carbofuran, the herbicide chlorpropham and the fungicide propamocarb, may impair activities of main drug transporters implicated in pharmacokinetics. The interactions of carbamates with solute carrier and ATP-binding cassette transporters were investigated using cultured transporter-overexpressing cells, reference substrates and spectrofluorimetry-, liquid chomatography/tandem mass spectrometry- or radioactivity-based methods. Aminocarb and carbofuran exerted no or minimal effects on transporter activities, whereas chlorpropham inhibited BCRP and OAT3 activities and propamocarb decreased those of OCT1 and OCT2, but cis-stimulated that of MATE2-K. Such alterations of transporters however required chlorpropham/propamocarb concentrations in the 5-50 µM range, likely not relevant to environmental exposure. Trans-stimulation assays and propamocarb accumulation experiments additionally suggested that propamocarb is not a substrate for OCT1, OCT2 and MATE2-K. These data indicate that some carbamate pesticides can interact in vitro with some drug transporters, but only when used at concentrations higher than those expected to occur in environmentally exposed humans.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Transporte Biológico , Carbamatos/metabolismo , Praguicidas/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Interações Medicamentosas , Humanos , Inseticidas , Proteínas de Neoplasias , Proteínas de Transporte de Cátions Orgânicos
17.
Chemosphere ; 256: 127069, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32447111

RESUMO

Pesticides are proposed as one reason for the worldwide decline in the reptile. Effects of pesticides on food intake and organ toxicity could affect wildlife populations dynamics. To explore the hepatotoxicity of alpha-cypermethrin (ACP) in reptiles, we designed a tri-trophic food chain with three concentrations (0, 2, and 20 mg/kgwet weight). Although the enzymes changes were similar between male and female lizards, the significant variations in anti-oxidative enzymes' activities, lactic dehydrogenase activities and acetylcholine esterase activities in liver and kidney suggesting that oxidative stress, decreased metabolic ability and neurotoxicity on lizards. The results of hepatic metabolomics showed that ACP could affect amino acid, energy and lipid metabolism on lizards. Comparing with female lizards, there were more significant changes of metabolites in male lizards. The histopathology analysis in the liver (such as hepatic lobule congestion and hepatocyte vacuolation) and kidney (such as renal tubule necrosis and glomerulus necrosis), dose- and gender dependent changes of lesions suggested the functions of organ were damaged. In summary, the reduction of detoxification and elimination capacities of the liver and kidney showed dose/gender-dependent in lizards.


Assuntos
Praguicidas/toxicidade , Piretrinas/toxicidade , Animais , Doença Hepática Induzida por Substâncias e Drogas/patologia , Relação Dose-Resposta a Droga , Feminino , Cadeia Alimentar , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Lagartos/metabolismo , Masculino , Síndromes Neurotóxicas/patologia , Estresse Oxidativo/fisiologia , Praguicidas/metabolismo
18.
J Toxicol Sci ; 45(5): 281-291, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32404560

RESUMO

Despite the developmental toxicity reported in animals, few epidemiologic studies have investigated the potential effects of prenatal exposure to pyrethroid pesticides (PYRs) on fetal growth. A birth cohort study was conducted to examine the association between prenatal exposure to PYRs and birth outcomes, and a nested case-control study was conducted in this cohort to evaluate the effects of PYR on congenital defects. The assessment of PYR exposure was based on self-reported household pesticide use and urinary PYR metabolite levels. We found that pregnant women in this region were ubiquitously exposed to low-level PYRs, although few reported household pesticide use. Women who often ate bananas or cantaloupes had a higher level of urinary 3-(2,2-dibromovinyl)-2,2-dimethylcyclopropane-1-carboxylic acid (DBCA), and the number of fruit types consumed by pregnant women was positively related to the concentrations of 3-phenoxybenzoic acid (3PBA) and total PYR metabolites (P < 0.05). Increased urinary 4-fluoro-3-phenoxybenzoic acid (4F3PBA), DBCA, and total PYR metabolites were associated with increased birth weight, length, and gestational age, and with decreased risk of small for gestational age (SGA) and/or premature birth. However, maternal household pesticides use was related to congenital anomalies. Thus, although prenatal exposure to low-dose PYRs promoted the fetal growth, the beneficial effects of fruit intake may outweigh the adverse effects of pesticide exposure. This study provided us an insight into the biological mechanisms for the effect of prenatal PYR exposure on fetal development, and suggested that further investigations in a larger study population with low-dose PYR exposure is needed.


Assuntos
Desenvolvimento Fetal/efeitos dos fármacos , Exposição Materna/efeitos adversos , Praguicidas/efeitos adversos , Piretrinas/efeitos adversos , Anormalidades Induzidas por Medicamentos/etiologia , Adulto , Estudos de Coortes , Feminino , Humanos , Troca Materno-Fetal , Praguicidas/metabolismo , Gravidez , Resultado da Gravidez , Piretrinas/metabolismo , Piretrinas/urina , Adulto Jovem
19.
Toxicology ; 438: 152446, 2020 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-32278049

RESUMO

Chiral pollutants are widely distributed in the environment; however, the enantioselective toxic effects of these chemicals have still not fully been clarified. Using wet experiments and computational toxicology, this story was to explore the static and dynamic toxic reactions between chiral diclofop-methyl and target protein at the enantiomeric level, and further unveil the microscopic mechanism of enantioselective toxicity of chiral pesticide. Steady-state and time-resolved results indicated that both (R)-/(S)-enantiomers can form the stable toxic conjugates with target protein and the bioaffinities were 1.156 × 104 M-1/1.734 × 104 M-1, respectively, and significant enantioselectivity was occurred in the reaction. Results of the modes of toxic action revealed that diclofop-methyl enantiomers located in the subdomain IIA, and the strength of important noncovalent interactions between (S)-diclofop-methyl and the residues was greater than that of (R)-diclofop-methyl. The Gibbs free energies of the chiral reactions were -26.89/-29.40 kJ mol-1 and -25.79/-30.08 kJ mol-1, respectively, which was consistent with the outcomes of photochemistry and site-specific competitive assay. Dynamic enantioselective processes explained that the impact of intrinsic protein conformational flexibility on the toxic reaction of (R)-diclofop-methyl was lower than that of (S)-diclofop-methyl, which originates from the conformational changes and spatial displacement of the four loop regions (i.e. h6↔h7, h1↔h2, h5↔h6, and h8↔h9). The quantitative data of circular dichroism spectra confirmed such results. Energy decomposition displayed that the electrostatic energy of the target protein-(S)-diclofop-methyl system (-25.86 kJ mol-1) was higher than that of the target protein-(R)-diclofop-methyl complex (-18.21 kJ mol-1). Some crucial residues such as Lys-195, Lys-199, Ser-202, and Trp-214 have been shown to be of different importance for the enantioselective toxicity of chiral diclofop-methyl. Obviously this scenario will contribute mechanistic clues to assessing the potential hazards of chiral environmental pollutants to the body.


Assuntos
Poluentes Ambientais/toxicidade , Éteres Difenil Halogenados/toxicidade , Praguicidas/toxicidade , Albumina Sérica Humana/metabolismo , Animais , Sítios de Ligação , Poluentes Ambientais/química , Poluentes Ambientais/metabolismo , Éteres Difenil Halogenados/química , Éteres Difenil Halogenados/metabolismo , Humanos , Simulação de Acoplamento Molecular , Praguicidas/química , Praguicidas/metabolismo , Ligação Proteica , Domínios Proteicos , Medição de Risco , Albumina Sérica Humana/química , Estereoisomerismo , Relação Estrutura-Atividade
20.
Crit Rev Oncol Hematol ; 150: 102950, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32339980

RESUMO

Incidence and mortality of thyroid cancer are increasing, thus making mandatory to improve the knowledge of disease etiology. The hypothesis of a role for anthropogenic chemicals is raising wide consideration. A series of occupational studies revealed that job exposures with high risk of chemical contamination were usually more prone to thyroid cancer development. These include shoe manufacture, preserving industry, building activities, pulp/papermaker industry and the wood processing, agricultural activities, and other work categories characterized by contact with chemicals, such as chemists and pharmacists. However, such epidemiological analyses cannot define a causal relationship. Thyroid-disrupting activity has emerged for a broad set of anthropogenic chemicals, with the best evidence being gained for polychlorinated biphenyls, polybrominated diphenyl ethers, dioxins, bisphenols, phthalates, pesticides, and heavy metals. A series of case-control studies, assessing exposure to thyroid-disrupting agents, as measured on biological matrices, have been recently performed providing the following insights: a) positive relationship with thyroid cancer was found for phthalates, bisphenols, the heavy metals cadmium, copper, and lead; b) polybrominated diphenyl ethers exposure showed no relationship with thyroid cancer c) controversial results were reported for polychlorinated biphenyls and pesticides. However, such studies cannot demonstrate the causal link with disease occurrence, as exposure is assessed after tumour development. Studies with different methodological approach are therefore required for defining the role of anthropogenic environmental chemicals in thyroid carcinogenesis.


Assuntos
Dioxinas/efeitos adversos , Poluentes Ambientais/efeitos adversos , Praguicidas/efeitos adversos , Bifenil Polibromatos/efeitos adversos , Bifenilos Policlorados/efeitos adversos , Glândula Tireoide/efeitos dos fármacos , Neoplasias da Glândula Tireoide/induzido quimicamente , Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Éteres Difenil Halogenados , Humanos , Praguicidas/metabolismo , Fenóis/toxicidade , Éteres Fenílicos/efeitos adversos , Glândula Tireoide/fisiologia
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