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1.
J Environ Qual ; 49(1): 128-139, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33016363

RESUMO

The Variable Volume Water Model (VVWM), the receiving water body model for the USEPA regulatory assessment of aquatic pesticide exposures, is composed of a set of static and quasistatic receiving water body conceptual models, but research comparing performance of these models to observations is limited. The water body models included are the constant volume (CVol), constant volume with overflow (CVO), and varying volume with overflow (VVO) models. This work quantified the performance of these three VVWM conceptual models compared with atrazine observations in 50 community water systems (CWSs), and the effect of alternative conceptual models on estimated environmental concentrations of pesticides in regulatory screening assessments. The 50 selected CWSs most relevant to the static and quasistatic VVWM concepts were small in size, with estimated time to peak flow of <1.5 d for consistency with the daily runoff assumption in USEPA landscape Pesticide Root Zone Model (PRZM). The CVO and VVO conceptual models resulted in similar distributions of bias across CWSs with the median result being close to no bias, but the CVol model resulted in overestimation in the majority of CWSs with median model bias near three times the observed values. At present, the CVol conceptual model parameterized with conservative input assumptions has been the regulatory standard invoked in VVWM, yet our results showed that a more physically correct conceptual model (CVO or VVO) could be invoked in regulatory exposure modeling for ecological risk assessment, reducing structural model bias while still allowing users to introduce conservative model inputs for screening purposes.


Assuntos
Atrazina , Praguicidas/análise , Praguicidas/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Modelos Teóricos , Água
2.
Ecotoxicol Environ Saf ; 203: 111013, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888588

RESUMO

Multiple pesticides originating from plant protection treatments and the treatment of pests infecting honey bees are frequently detected in beehive matrices. Therefore, winter honey bees, which have a long life span, could be exposed to these pesticides for longer periods than summer honey bees. In this study, winter honey bees were exposed through food to the insecticide imidacloprid, the fungicide difenoconazole and the herbicide glyphosate, alone or in binary and ternary mixtures, at environmental concentrations (0 (controls), 0.1, 1 and 10 µg/L) for 20 days. The survival of the honey bees was significantly reduced after exposure to these 3 pesticides individually and in combination. Overall, the combinations had a higher impact than the pesticides alone with a maximum mortality of 52.9% after 20 days of exposure to the insecticide-fungicide binary mixture at 1 µg/L. The analyses of the surviving bees showed that these different pesticide combinations had a systemic global impact on the physiological state of the honey bees, as revealed by the modulation of head, midgut and abdomen glutathione-S-transferase, head acetylcholinesterase, abdomen glucose-6-phosphate dehydrogenase and midgut alkaline phosphatase, which are involved in the detoxification of xenobiotics, the nervous system, defenses against oxidative stress, metabolism and immunity, respectively. These results demonstrate the importance of studying the effects of chemical cocktails based on low realistic exposure levels and developing long-term tests to reveal possible lethal and adverse sublethal interactions in honey bees and other insect pollinators.


Assuntos
Abelhas/fisiologia , Fungicidas Industriais/toxicidade , Herbicidas/toxicidade , Inseticidas/toxicidade , Praguicidas/toxicidade , Animais , Dioxolanos/toxicidade , Sinergismo Farmacológico , Glicina/análogos & derivados , Glicina/toxicidade , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Polinização/efeitos dos fármacos , Triazóis/toxicidade
3.
Ecotoxicol Environ Saf ; 203: 111046, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888614

RESUMO

Agricultural pesticides serve as effective controls of unwanted weeds and pests. However, these same chemicals can exert toxic effects in non-target organisms. To determine chemical modes of action, the toxicity ratio (TR) and critical body residues (CBRs) of 57 pesticides were calculated for Daphnia magna. Results showed that the CBR values of inert compounds were close to a constant while the CBR values of pesticides varied over a wider range. Although herbicides are categorized as specifically-acting compounds to plants, herbicides did not exhibit excess toxicity to Daphnia magna and were categorized as inert compounds with an average logTR = 0.41, which was less than a threshold of one. Conversely, fungicides and insecticides exhibited strong potential for toxic effects to Daphnia magna with an average logTR >2. Many of these chemicals act via disruption of the nervous, respiratory, or reproductive system, with high ligand-receptor binding activity which leads to higher toxicity for Daphnia magna. Molecular docking using acetylcholinesterase revealed that fungicides and insecticides bind more easily with the biological macromolecule when compared with inert compounds. Quantitative structure-activity relationship (QSAR) analysis revealed that the toxicity of fungicides was mainly dependent upon the heat of formation and polar surface area, while the toxicity of insecticides was more related to hydrogen-bond properties. This comprehensive analysis reveals that there are specific differences in toxic mechanisms between fungicides and insecticides. These results are useful for determining relative risk associated with pesticide exposure to aquatic crustaceans, such as Daphnia magna.


Assuntos
Daphnia/efeitos dos fármacos , Modelos Biológicos , Praguicidas/química , Praguicidas/toxicidade , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Acetilcolinesterase/metabolismo , Animais , Daphnia/metabolismo , Relação Dose-Resposta a Droga , Fungicidas Industriais/química , Fungicidas Industriais/toxicidade , Herbicidas/química , Herbicidas/toxicidade , Ligação de Hidrogênio , Inseticidas/química , Inseticidas/toxicidade , Simulação de Acoplamento Molecular , Resíduos de Praguicidas/metabolismo , Relação Quantitativa Estrutura-Atividade
4.
Ecotoxicol Environ Saf ; 205: 111312, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32956863

RESUMO

Chlorpyrifos (CPF) is one of the most frequently used pesticide in extensive agriculture around the world and can be incorporated by humans and animals with possible consequences on health. The effects of this pesticide on carcinogenesis are not clear and there is no consensus concerning the risks of this compound. In previous work, we demonstrated that CPF induces proliferation of breast cancer cells both in vivo and in vitro. In this work we investigate whether CPF promotes the epithelial-mesenchymal transition (EMT) in breast cancer cells. Herein, we demonstrate that 50 µM CFP induces invasion in MCF-7 and MDA-MB-231 cells. In addition, 0.05 and 50 µM CPF increases migration in both cell lines. In MCF-7 cells, 0.05 and 50 µM CPF increase the metalloprotease MMP2 expression and decrease E-Cadherin and ß-Catenin expression diminishing their membrane location. Furthermore, 50 µM CPF induces Vimentin expression and Slug nuclear translocation in MCF-7 cells. 0.05 and 50 µM CPF increase MMP2 gelatinolytic activity and expression, decrease ß-Catenin expression and increase Vimentin expression in MDA-MB-231 cells. Inhibition of the oncoprotein c-Src reverses all the effects induced by CPF in MDA-MB-231 but not in MCF-7 indicating that c-Src is a kinase with a crucial role in the cells which grow in an estrogen-independent way. In MCF-7 cells both c-Src and estrogen receptor alpha must be blocked to completly inhibit the CPF-mediated effects. Our results show for the first time that the exposure to subthreshold concentrations of CPF promotes the modulation of EMT-molecular markers and pathways. These results, together with the ubiquitous distribution of the pesticide CPF, make it of utmost importance to take measures to minimize the risk of exposure to this compound.


Assuntos
Movimento Celular/efeitos dos fármacos , Clorpirifos/toxicidade , Disruptores Endócrinos/toxicidade , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Praguicidas/toxicidade , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proteína Tirosina Quinase CSK/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Relação Dose-Resposta a Droga , Transição Epitelial-Mesenquimal/genética , Receptor alfa de Estrogênio/genética , Feminino , Humanos , Células MCF-7 , Metaloproteinase 2 da Matriz/genética , Transdução de Sinais
5.
Ecotoxicol Environ Saf ; 205: 111314, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32956866

RESUMO

Brazilian freshwater ecosystems are continuously exposed to pesticides and domestic sewage. The Uruguay River was chosen for this study because of its international importance, as it flows through Brazil, Argentina, and Uruguay. It receives contaminants such as pesticides and domestic residues. Thus, the aim of this study to assess the accumulation of pesticides in muscle of the fish Astyanax jacuhiensis, its biochemical responses, and the presence of pesticides in water. In total, seven pesticides were registered in water from both river sites. Eight pesticides were detected in fish muscle. The biochemical responses showed that brain lipid peroxidation (LPO) and protein carbonyl (PC) in A. jacuhiensis were higher in the summer. Muscle showed the highest LPO levels in the spring and the highest PC in the summer. Liver LPO and PC levels were higher in the spring and summer. In the gills, the PC was higher in the spring and the LPO in the spring and winter. In the brain and in the gills, glutathione-S-transferase activity was high in the summer and autumn. Catalase activity was lower during the winter and spring. Non-protein thiol (NPSH) levels were lower in the brain in the winter and spring. Muscle tissue showed lower NPSH in the winter (site 1). Liver NPSH showed increased levels in liver in the spring and winter (site 2). The biochemical results clearly is related to pesticides and/or to the presence of other contaminants in the water such as metals or domestic sewage. The accumulation of pesticides in fish muscle added evidence that pesticides have been used in the area surrounding the Uruguay River. In conclusion, the biomarkers assayed in the present study could be used in future investigations considering other sampling sites along Uruguay River.


Assuntos
Characidae/fisiologia , Monitoramento Ambiental , Praguicidas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Brasil , Characidae/metabolismo , Caraciformes/metabolismo , Caraciformes/fisiologia , Ecossistema , Brânquias/metabolismo , Peroxidação de Lipídeos , Metais/metabolismo , Praguicidas/análise , Rios/química , Estações do Ano , Poluentes Químicos da Água/análise
6.
Sci Total Environ ; 745: 141285, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-32943215

RESUMO

During water years (WY) 2013-2017, the U.S. Geological Survey, National Water-Quality Assessment (NAWQA) Project, sampled the National Water Quality Network - Rivers and Streams (NWQN) year-round and reported on 221 pesticides at 72 sites across the United States in agricultural, developed, and mixed land use watersheds. The Pesticide Toxicity Index (PTI) was used to estimate the potential chronic and acute toxicity to three taxonomic groups - fish, cladocerans, and benthic invertebrates. For invertebrates (either cladocerans, benthic invertebrates, or both), the maximum PTI score exceeded the predicted acute toxicity screening level at 18 of the 72 sites (25%) at some point during WY 2013-2017. The predicted toxicity of a single pesticide compound was found to overwhelm the toxicity of other pesticides in the mixtures after concentrations were toxicity weighted. For this study, about 71%, 72%, and 92% of the Fish-, Cladoceran-, and Benthic Invertebrate-PTI scores, respectively, had one pesticide compound primarily contributing to sample potential toxicity (>50%). There were 17 (13 insecticides, 2 herbicides, 1 fungicide, and 1 synergist) of the 221 pesticide compounds analyzed that were the primary drivers of potential toxicity in each water sample in which the PTI and TUmax (toxic unit score for the pesticide that makes the single largest contribution to the PTI) scores were above predicted chronic (>0.1) or acute (>1) toxicity levels for one of the three taxa. For cladocerans and benthic invertebrates, the drivers of predicted chronic (>0.1) and acute (>1) PTIs were mostly insecticides. For cladocerans, the pesticide compounds driving the PTI scores were bifenthrin, carbaryl, chlorpyrifos, diazinon, dichlorvos, dicrotophos, diflubenzuron, flubendiamide, and tebupirimfos. For benthic invertebrates, atrazine (an herbicide), as well as the insecticides - bifenthrin, carbaryl, carbofuran, chlorpyrifos, diazinon, dichlorvos, fipronil, imidacloprid, and methamidophos - were the drivers of predicted toxicity. For fish, there were three pesticide types that contributed the most to predicted chronic (>0.1) PTIs - acetochlor, an herbicide; carbendazim, a fungicide degradate; and piperonylbutoxide, a synergist.


Assuntos
Praguicidas/análise , Praguicidas/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Animais , Monitoramento Ambiental , Rios , Estados Unidos , Água
7.
PLoS One ; 15(8): e0237876, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32817683

RESUMO

To explain the asymmetrical abundance of native Frankliniella intonsa (Trybom) (Thysanoptera: Thripidae) and invasive Frankliniella occidentalis (Pergande) in the fields, we examined differential susceptibility to pesticides and environmental conditions, i.e., nine combinations of temperatures and relative humidities (RHs). We found adult female F. intonsa to be more susceptible to most of the tested insecticides as compared to F. occidentalis. Chlorfenapyr was most toxic to both thrips' species. In the evaluation of environment conditions in the adult stage, F. intonsa survived 2.5 and 2.4-fold longer as RH increased at 20 and 25 °C, respectively, whereas F. occidentalis survived 1.8 and 1.6-fold longer, respectively. In both pupal and larval stage, no significant effect of interaction of temperatures and RHs was found between the two species. In conclusion, the insecticides tested differed considerably in their species-specific toxicity, and F. intonsa was generally more susceptible to the insecticides, while at the same time survivorship was better at higher RH conditions than F. occidentalis. Thus, differences in the relative susceptibility to changing environmental conditions, especially humidity, may be an underlying mechanism for the recent dominance of F. intonsa over F. occidentalis in the strawberry plastic greenhouse in Korea.


Assuntos
Inseticidas/toxicidade , Praguicidas/toxicidade , Piretrinas/toxicidade , Tisanópteros/efeitos dos fármacos , Animais , Feminino , Fragaria/parasitologia , Umidade , Espécies Introduzidas , Larva/efeitos dos fármacos , Pupa/efeitos dos fármacos , República da Coreia , Especificidade da Espécie , Temperatura
8.
Aquat Toxicol ; 227: 105589, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32841884

RESUMO

Pesticides have an impact on the aquatic environment, with ecological effects. The regulation of this impact is of key importance. One of the components of the planning of agricultural and industrial activities is the development of databases and models in order to identify substances that may cause damage. In this study, a quantitative structure-activity relationship (QSAR) approach was established for the prediction of acute toxicity toward rainbow trout of various pesticides. The so-called index of ideality of correlation is the main component of this approach. The validation of this approach has been carried out with three random splits into the training and validation sets. The range of statistical quality of models obtained here for the validation set is R2 = [0.81-0.86] and RMSE = [0.55-0.65].


Assuntos
Modelos Teóricos , Oncorhynchus mykiss , Praguicidas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Bases de Dados Factuais , Método de Monte Carlo , Praguicidas/química , Relação Quantitativa Estrutura-Atividade , Poluentes Químicos da Água/química
9.
Ecotoxicol Environ Saf ; 202: 110940, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800223

RESUMO

Recent evidence indicates that chronic, low-dose exposure to mixtures of pesticides can cause adverse responses in a variety of cells, tissues and organs, although interactions between pesticides circulating in the blood and cancer cells remain largely unexplored. The aim of this study was to investigate the potential of a mixture of four pesticides to induce multidrug resistance against the chemotherapeutic agents cisplatin, 5-fluorouracil and temozolomide in the human U87 glioblastoma cell line, and to explore the molecular mechanisms underlying this resistance. We found that the repeated administration of the pesticide mixture (containing the insecticides chlorpyrifos-ethyl and deltamethrin, the fungicide metiram, and the herbicide glyphosate) induced a strong drug resistance in U87 cells. The resistance was durable and transferred to subsequent cell generations. In addition, we detected a significant over-expression of the ATP-binding cassette (ABC) membrane transporters P-gp/ABCB1 and BRCP/ABCG2 as well as a glutathione-S-transferase (GST)/M1-type cellular detoxification function, known to have important roles in multidrug resistance, thus providing molecular support for the acquired multidrug resistance phenotype and shedding light on the mechanism of resistance. We further determined that there was lower mortality in the resistant brain tumor cells and that the mitochondrial apoptosis pathway was activated at a lower rate after chemotherapy compared to non-resistant control cells. In addition, multidrug-resistant cells were found to have both higher motility and wound-healing properties, suggesting a greater metastatic potential. Our results suggest that the investigation of P-gp, BRCP and GST/M1 multidrug resistance gene expression and/or protein levels in biopsy specimens of brain tumor patients who were at risk of pesticide exposure could be beneficial in determining chemotherapy dose and prolonging patient survival.


Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Praguicidas/toxicidade , Testes de Toxicidade Crônica , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Cisplatino , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistência a Múltiplos Medicamentos/genética , Resistencia a Medicamentos Antineoplásicos/genética , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas de Neoplasias/farmacologia
10.
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
11.
PLoS One ; 15(7): e0229052, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32614853

RESUMO

Rice paddy irrigation ponds can sustain surprisingly high taxonomic richness and make significant contributions to regional biodiversity. We evaluated the impacts of pesticides and other environmental stressors (including eutrophication, decreased macrophyte coverage, physical habitat destruction, and invasive alien species) on the taxonomic richness of freshwater animals in 21 irrigation ponds in Japan. We sampled a wide range of freshwater animals (reptiles, amphibians, fishes, mollusks, crustaceans, insects, annelids, bryozoans, and sponges) and surveyed environmental variables related to pesticide contamination and other stressors listed above. Statistical analyses comprised contraction of highly correlated environmental variables, best-subset model selection, stepwise model selection, and permutation tests. Results showed that: (i) probenazole (fungicide) was a significant stressor on fish (i.e., contamination with this compound had a significantly negative correlation with fish taxonomic richness), (ii) the interaction of BPMC (insecticide; also known as fenobucarb) and bluegill (invasive alien fish) was a significant stressor on a "large insect" category (Coleoptera, Ephemeroptera, Hemiptera, Lepidoptera, Odonata, and Trichoptera), (iii) the interaction of BPMC and concrete bank protection was a significant stressor on an "invertebrate" category, (iv) the combined impacts of BPMC and the other stressors on the invertebrate and large insect categories resulted in an estimated mean loss of taxonomic richness by 15% and 77%, respectively, in comparison with a hypothetical pond with preferable conditions.


Assuntos
Invertebrados/efeitos dos fármacos , Praguicidas/toxicidade , Animais , Biodiversidade , Carbamatos/toxicidade , Ecossistema , Monitoramento Ambiental , Espécies Introduzidas , Invertebrados/fisiologia , Tanques , Tiazóis/toxicidade , Vertebrados/fisiologia
12.
Nat Commun ; 11(1): 3614, 2020 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-32681015

RESUMO

Larval metamorphosis and recruitment represent critical life-history transitions for most teleost fishes. While the detrimental effects of anthropogenic stressors on the behavior and survival of recruiting fishes are well-documented, the physiological mechanisms that underpin these patterns remain unclear. Here, we use pharmacological treatments to highlight the role that thyroid hormones (TH) play in sensory development and determining anti-predator responses in metamorphosing convict surgeonfish, Acanthurus triostegus. We then show that high doses of a physical stressor (increased temperature of +3 °C) and a chemical stressor (the pesticide chlorpyrifos at 30 µg L-1) induced similar defects by decreasing fish TH levels and affecting their sensory development. Stressor-exposed fish experienced higher predation; however, their ability to avoid predation improved when they received supplemental TH. Our results highlight that two different anthropogenic stressors can affect critical developmental and ecological transitions via the same physiological pathway. This finding provides a unifying mechanism to explain past results and underlines the profound threat anthropogenic stressors pose to fish communities.


Assuntos
Peixes/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Praguicidas/toxicidade , Glândula Tireoide/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Clorpirifos/toxicidade , Poluição Ambiental/efeitos adversos , Metamorfose Biológica/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Glândula Tireoide/metabolismo , Hormônios Tireóideos/metabolismo
13.
J Toxicol Environ Health B Crit Rev ; 23(6): 255-275, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32568623

RESUMO

Gap junctions in liver, as in other organs, play a critical role in tissue homeostasis. Inherently, these cellular constituents are major targets for systemic toxicity and diseases, including cancer. This review provides an overview of chemicals that compromise liver gap junctions, in particular biological toxins, organic solvents, pesticides, pharmaceuticals, peroxides, metals and phthalates. The focus in this review is placed upon the mechanistic scenarios that underlie these adverse effects. Further, the potential use of gap junctional activity as an in vitro biomarker to identify non-genotoxic hepatocarcinogenic chemicals is discussed.


Assuntos
Comunicação Celular/efeitos dos fármacos , Junções Comunicantes/efeitos dos fármacos , Fígado/efeitos dos fármacos , Animais , Conexinas/biossíntese , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Fígado/metabolismo , Metais/toxicidade , Peróxidos/toxicidade , Praguicidas/toxicidade , Ácidos Ftálicos/toxicidade , Medição de Risco , Solventes/toxicidade , Toxinas Biológicas/toxicidade
14.
J Environ Sci Health B ; 55(8): 719-725, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32538258

RESUMO

The industrialization of the agricultural sector has significantly increased the use of chemicals such as pesticides. Therefore, exposure to them is unavoidable, which makes it necessary to assess their safety for humans at actual exposure doses. This paper aims to determine toxicity of three types of pesticides toward human immune cells (HL-60 and U-937): glyphosate (GLY), deltamethrin (DEL), and chlorothalonil (CHL). Cell viability, membrane integrity, inflammation induction, and antioxidant activity were evaluated to determine differences in cellular response to the tested plant protection agents. In experimental models, all tested substances caused increased mortality of cells after only 24 h. Cell membrane damage was recorded under DEL and CHL influences. The largest disintegration of the cell membrane was due to the action of 100 µg/mL DEL for U-937 and CHL at 1 µg/mL for HL-60. GLY at a concentration of 3,600 µg/mL caused significant peroxidation of U-937 cells' lipids. CHL-induced inflammation in both types of cells tested. DEL and GLY also induced antioxidant activity in cells. These results lead to the conclusion that the tested pesticides act cytotoxically to the cells of the human immune system in doses to which both farmers and consumers are exposed.


Assuntos
Glicina/análogos & derivados , Sistema Imunitário/efeitos dos fármacos , Nitrilos/toxicidade , Praguicidas/toxicidade , Piretrinas/toxicidade , Agricultura , Antioxidantes/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/imunologia , Sobrevivência Celular/efeitos dos fármacos , Fazendeiros , Glicina/toxicidade , Células HL-60 , Humanos , Sistema Imunitário/citologia , Peroxidação de Lipídeos/efeitos dos fármacos , Exposição Ocupacional , Testes de Toxicidade
15.
Ecotoxicol Environ Saf ; 201: 110812, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32512419

RESUMO

Pesticides are widely used chemical compounds in agriculture to destroy insects, pests and weeds. In modern era, they form an indispensable part of agricultural and health practices. Globally, nearly 3 billion kg of pesticides are used every year with a budget of ~40 billion USD. This extensive usage has increased the crop yield as well as led to significant reduction in harvest losses and thereby, enhanced food availability. On the other hand, indiscriminate usage of these chemicals has led to several environmental implications and caused adverse effects on human health. Epidemiological evidences have revealed the harmful effects of pesticides exposure on various organs including liver, brain, lungs and colon. Recent investigations have shown that pesticides can also lead to fatal consequences such as cancer among individuals. These chemicals enter ecosystem, thus hampering the sensitive environmental equilibrium through bio-accumulation. Due to their non-biodegradable nature, they can persist in nature for years and are regarded as potent biohazard. Worldwide, very few surveillance methods have been considered, which can bring awareness among the individuals, therefore the present review is an attempt to delineate consequences induced by various types of pesticide exposure on the environment. Further, the prospective of biopesticides use could facilitate the increase of crop production without compromising human health.


Assuntos
Agentes de Controle Biológico/toxicidade , Exposição Ambiental/efeitos adversos , Poluentes Ambientais/toxicidade , Praguicidas/toxicidade , Agentes de Controle Biológico/química , Produção Agrícola/métodos , Ecossistema , Exposição Ambiental/análise , Poluentes Ambientais/química , Humanos , Praguicidas/química
16.
Ecotoxicol Environ Saf ; 201: 110829, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32531577

RESUMO

The toxicity of the insecticide carbofuran and herbicide diuron (individually and in mixture) to the invertebrates Paramecium caudatum and Ceriodaphnia silvestrii was evaluated. Acute and chronic toxicity tests were carried out with the diuron and carbofuran active ingredients and their commercial products, Diuron Nortox® 500 SC and Furadan® 350 SC, respectively. Individual toxicity tests showed that C. silvestrii was more sensitive to both carbofuran and diuron than P. caudatum. In single exposures, both pesticides caused adverse effects to C. silvestrii in environmentally relevant concentrations (48 h EC50 = 0.001 mg L-1 and 8 d LOEC = 0.00038 mg L-1 for formulated carbofuran; 8 d LOEC < 0.05 mg L-1 for formulated diuron). For P. caudatum, carbofuran and diuron in single exposures were only slightly toxic (24 h IC50 = 5.1 mg L-1 and 6.9 mg L-1 for formulated carbofuran and diuron, respectively). Acute and chronic exposures to diuron and carbofuran mixtures caused significant deviations of the toxicity predicted by the Concentration Addition and Independent Action reference models for both test species. For the protozoan P. caudatum, a dose-dependent deviation was verified for mortality, with synergism caused mainly by carbofuran and antagonism caused mainly by diuron. For protozoan population growth, however, an antagonistic deviation was observed when the active ingredient mixtures were tested. In the case of C. silvestrii, antagonism at low concentrations and synergism at high concentrations were revealed after acute exposure to active ingredient mixtures, whereas for reproduction an antagonistic deviation was found. Commercial formulation mixtures presented significantly higher toxicity than the active ingredient mixtures. Our results showed that carbofuran and diuron interact and cause different toxic responses than those predicted by the individually tested compounds. Their mixture toxicity should therefore be considered in risk assessments as these pesticides are likely to be present simultaneously in edge-of-field waterbodies.


Assuntos
Carbofurano/toxicidade , Cladóceros/efeitos dos fármacos , Cladóceros/fisiologia , Diurona/toxicidade , Paramecium caudatum/efeitos dos fármacos , Praguicidas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Testes de Toxicidade
17.
Chemosphere ; 258: 127217, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32535437

RESUMO

The widespread use of pesticides has received increasing attention in regulatory agencies because their extensive overuse and various adverse effects on all living organisms. Organizations such as EPA and ECHA have published laws that pesticides should be fully evaluated before bring them to market. In the present study, we evaluated the pesticides toxicity using the Quantitative Structural-Activity Relationship (QSAR) method. The models for the single class pesticides (herbicides, insecticides and fungicides) as well as the general class pesticides (the combined dataset plus some microbicides, molluscicides, etc.) were developed using the Genetic Algorithm and Multiple Linear Regression method. The internal and external validation results suggested that all the obtained models were stable and predictive. According to the modeling descriptors, the lipophilic descriptors contributed positively while all the electrotopological state descriptors showed a negative contribution, their presences in every model verified the conspicuous influence of molecular lipophilicity and hydrophilicity on the pesticides toxicity. However, the influence of topological structure descriptors was different and varies with the physiochemical information they encode. Finally, the models presented in this paper would help assess the pesticides toxicity against Americamysis bahia, shorten test time, and reduce the cost of pesticides risk assessment.


Assuntos
Crustáceos/efeitos dos fármacos , Modelos Teóricos , Praguicidas/química , Praguicidas/toxicidade , Animais , Bases de Dados Factuais , Fungicidas Industriais/química , Fungicidas Industriais/toxicidade , Herbicidas/química , Herbicidas/toxicidade , Interações Hidrofóbicas e Hidrofílicas , Inseticidas/química , Inseticidas/toxicidade , Modelos Lineares , Relação Quantitativa Estrutura-Atividade
18.
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
19.
Food Chem Toxicol ; 141: 111418, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: covidwho-345861

RESUMO

Occupational, residential, dietary and environmental exposures to mixtures of synthetic anthropogenic chemicals after World War II have a strong relationship with the increase of chronic diseases, health cost and environmental pollution. The link between environment and immunity is particularly intriguing as it is known that chemicals and drugs can cause immunotoxicity (e.g., allergies and autoimmune diseases). In this review, we emphasize the relationship between long-term exposure to xenobiotic mixtures and immune deficiency inherent to chronic diseases and epidemics/pandemics. We also address the immunotoxicologic risk of vulnerable groups, taking into account biochemical and biophysical properties of SARS-CoV-2 and its immunopathological implications. We particularly underline the common mechanisms by which xenobiotics and SARS-CoV-2 act at the cellular and molecular level. We discuss how long-term exposure to thousand chemicals in mixtures, mostly fossil fuel derivatives, exposure toparticle matters, metals, ultraviolet (UV)-B radiation, ionizing radiation and lifestyle contribute to immunodeficiency observed in the contemporary pandemic, such as COVID-19, and thus threaten global public health, human prosperity and achievements, and global economy. Finally, we propose metrics which are needed to address the diverse health effects of anthropogenic COVID-19 crisis at present and those required to prevent similar future pandemics.


Assuntos
Poluentes Atmosféricos/toxicidade , Betacoronavirus , Infecções por Coronavirus/epidemiologia , Praguicidas/toxicidade , Pneumonia Viral/epidemiologia , Xenobióticos/toxicidade , Animais , Antivirais/uso terapêutico , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/fisiopatologia , Dieta , Epidemias , Humanos , Sistema Imunitário/efeitos dos fármacos , Pandemias , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/fisiopatologia , Prevalência , Receptores de Hidrocarboneto Arílico/metabolismo , Fatores de Risco , Transdução de Sinais/efeitos dos fármacos , Tempo
20.
Tunis Med ; 98(2): 123-130, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32395801

RESUMO

BACKGROUND: Cardiac arrest (CA) is a public health problem, with various etiologies and a fatal issue in 90-95% of cases. Toxin-induced cardiac arrests (TICA) are poorly described. Scarcity of national data prompted us to carry-out this study. AIM: To determine TICA frequency in a Tunisian reference center in toxicology and its hospital prognosis, and to describe its clinical and therapeutic aspects Methods : Data were collected retrospectively over an 8-years period. We included patients admitted for post-CA care with highly suspected or confirmed TICA. Clinical and toxicological data were recorded. RESULTS: We recorded 21 cases of TICA, which represented 48.8% of CA. A single toxic agent was incriminated in 90% of cases. Main causative agents identified in our series were pesticides and betablockers: chloralosed (n = 6), carbamate inhibitor of cholinesterase (n = 5), acebutolol (n = 4) and organophosphate (n = 2). One case of opiates and cocaine poisoning was reported. Median duration of "no flow" was 0 minutes. Mean duration of "low flow" was 13.74±9.15 minutes. An initial shockable rhythm was noted only in three patients. Mortality rate was 76% (16/21). Four of the five survivors had a Cerebral Performance Category Scale (CPC) 1, only one patient survived with a CPC 3. Factors associated with mortality were : the duration of "low flow" (p=0.02) and APACHE II score (p=0.014). APACHE II≥29 was the only independent factor (OR=2.0, 95%CI [1.07;3.71]). CONCLUSION: TICA were most frequently provoked by pesticides, mortality was high and was independently predicted by APACHE II score.


Assuntos
Cardiotoxicidade , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Parada Cardíaca/induzido quimicamente , Parada Cardíaca/diagnóstico , Parada Cardíaca/terapia , Toxinas Biológicas/toxicidade , Antagonistas Adrenérgicos beta/toxicidade , Cardiotoxicidade/diagnóstico , Cardiotoxicidade/epidemiologia , Cardiotoxicidade/etiologia , Cardiotoxicidade/terapia , Cocaína/envenenamento , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/terapia , Parada Cardíaca/epidemiologia , Mortalidade Hospitalar , Hospitalização/estatística & dados numéricos , Humanos , Incidência , Mortalidade , Organofosfatos/toxicidade , Praguicidas/toxicidade , Estudos Retrospectivos , Fatores de Risco , Toxinas Biológicas/classificação , Resultado do Tratamento , Tunísia/epidemiologia
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