Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 4.975
Filtrar
1.
Adv Exp Med Biol ; 1121: 21-31, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31392649

RESUMO

The increasing prevalence of non communicable diseases (NCDs) poses main challenges to global public health. Various environmental exposures to different chemicals and pollutants might interact with genetic and epigenetic mechanisms resulting in the development of NCDs. Among these environmental exposures, endocrine disrupting chemicals (EDCs) consist of a group of compounds with potential adverse health effects and the interference with the endocrine system. They are mostly used in food constituents, packaging industries and pesticides. Growing number of in vitro, in vivo, and epidemiological studies documented the link of EDC exposure with obesity, diabetes, and metabolic syndrome, which are the underlying factors for development of NCDs. Prevention of exposure to EDCs and reduction of their production should be underscored in strategies for primordial prevention of NCDs.


Assuntos
Disruptores Endócrinos , Exposição Ambiental , Poluentes Ambientais , Doenças não Transmissíveis , Disruptores Endócrinos/toxicidade , Exposição Ambiental/prevenção & controle , Poluentes Ambientais/toxicidade , Humanos , Praguicidas/toxicidade
2.
Toxicol Lett ; 315: 96-106, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31386889

RESUMO

We investigate the long-term effect of very-low dose exposure to a mixture of six pesticides associated with hydrophilic vitamin deficiency on the neurobehavioral outcomes of rats. Two hundred Wistar rats were divided into four groups, two control groups, a vitamin sufficient control group and a vitamin deficiency control group and 2 test groups, a vitamin sufficient test group, and a vitamin deficiency group. The test groups were exposed for 9 months to a mixture of diquat, imazamox, imazethapyr, tepraloxydin, bentazone and acifluorfen in doses of 0.01xNOAEL (mg/kg bw/day). After 9 months of exposure, the behavior changes were evaluated by open field test and elevated plus maze test and the memory was assessed by passive avoidance test. Chronic vitamin deficiency decreased locomotor and special orientation activity and increased anxiety-like behavior in rats. Exposure to very low doses of a mixture of 6 pesticides caused central nervous effects, manifested as decreased locomotor activity, and increased anxiety levels. Vitamin deficiency and low dose chronic pesticides mixture exposure thus affected the central nervous system, especially long-term memory.


Assuntos
Deficiência de Vitaminas/complicações , Deficiência de Vitaminas/fisiopatologia , Aprendizagem da Esquiva/efeitos dos fármacos , Aprendizagem em Labirinto/efeitos dos fármacos , Doenças do Sistema Nervoso/induzido quimicamente , Doenças do Sistema Nervoso/fisiopatologia , Praguicidas/toxicidade , Animais , Modelos Animais de Doenças , Masculino , Ratos , Ratos Wistar
3.
Ecotoxicol Environ Saf ; 182: 109400, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31276883

RESUMO

This study was designed to investigate skeletal changes in Podocnemis unifilis embryos derived from artificially incubated eggs exposed to different concentrations of atrazine, glyphosate or atrazine and glyphosate mixture. Forty-two eggs were randomly allocated to one of seven trays containing vermiculite treated distilled water (control group) or the following solutions: 2 or 200 µg L-1 of atrazine (groups A1 and A2 respectively); 65 or 6500 µg L-1 of glyphosate (groups G1 and G2 respectively); 2 µg L-1 and 65 µg L-1 or 200 µg L-1 and 6500 µg L-1 of atrazine and glyphosate mixture (groups AG1 and AG2 respectively). Three eggs per tray were randomly collected on days 30 and 50 of the incubation period. Embryos were submitted to soft tissue diaphanization and stained with Alizarin red S or Alcian blue for morphological analysis of bone and cartilage tissues; histological analysis was performed to confirm ossification changes. Findings were compared between groups. Morphological changes were limited to sclerotic ring features and number of ribs. Malformations rates differed significantly (p < 0.05) between embryos in the control and treated groups A2, AG1 and AG2. Concurrent exposure to atrazine and glyphosate did not affect the presence or severity of embryonic malformations and was not associated with appendicular skeleton changes in P. unifilis embryos. However, further studies focusing on the axial skeleton with particular emphasis on rib abnormalities are warranted.


Assuntos
Atrazina/toxicidade , Glicina/análogos & derivados , Óvulo/efeitos dos fármacos , Praguicidas/toxicidade , Testes de Toxicidade , Animais , Atrazina/análise , Desenvolvimento Ósseo , Osso e Ossos/química , Cartilagem , Ovos , Glicina/toxicidade , Osteogênese , Tartarugas
4.
Ecotoxicol Environ Saf ; 182: 109420, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31299472

RESUMO

Mancozeb (MZ), chlorothalonil (CT), and thiophanate methyl (TM) are pesticides commonly used in agriculture due to their efficacy, low acute toxicity to mammals, and short environmental persistence. Although the toxic effects of these pesticides have been previously reported, studies regarding their influence on the immune system are limited. As such, this study focused on the immunomodulatory effect of MZ, CT, and TM pesticides on macrophage cells. RAW 264.7 cells were exposed to a range of concentrations (0.1-100 µg/mL) of these pesticides. CT exposure promoted an increase in reactive oxygen species (ROS) and nitric oxide (NO) levels. The MTT and ds-DNA assay results demonstrated that MZ, CT, and TM exposure induced macrophage proliferation. Moreover, MZ, CT, and TM promoted cell cycle arrest at S phase, strongly suggesting macrophage proliferation. The levels of pro-inflammatory cytokines (IL-1ß, IL-6, TNF-α, and IFN-γ) and caspases (caspase 1, 3, and 8) in macrophages exposed to MZ, CT, and TM pesticides increased, whereas the anti-inflammatory cytokine levels decreased. These results suggest that MZ, CT, and TM exert an immunomodulatory effect on the immune system, inducing macrophage activation and enhancing the inflammatory response.


Assuntos
Praguicidas/toxicidade , Animais , Citocinas/metabolismo , Imunomodulação , Interleucina-1beta/metabolismo , Macrófagos/efeitos dos fármacos , Maneb/toxicidade , Óxido Nítrico/metabolismo , Nitrilos/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Tiofanato/toxicidade , Testes de Toxicidade , Fator de Necrose Tumoral alfa/metabolismo , Zineb/toxicidade
5.
Inorg Chem ; 58(15): 9773-9784, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31318533

RESUMO

In recent years, transition metal complexes have been developed for catalytical degradation of a phosphate ester bond, particularly in RNA and DNA; however, less consideration has been given for development of complexes for the degradation of a phosphorothioate bond, as they are the foremost used pesticides in the environment and are toxic to human beings. In this context, we have developed copper complexes of benzimidazolium based ligands for catalytical degradation of a series of organophosphates (parathion, paraoxon, methyl-parathion) at ambient conditions. The copper complexes (assigned as N1-N3) were characterized using single X-ray crystallography which revealed that all three complexes are mononuclear and distorted square planner in geometry. Further, the solution state studies of the prepared complexes were carried out using UV-visible absorption, fluorescence spectroscopy, and cyclic voltametry. The complexes N1 and N2 have benzimidazolium ionic liquid as base attached with two 2-mercapto-benzimidazole pods, whereas complex N3 contains a nonionic ligand. The synthesized copper complexes were evaluated for their catalytic activity for degradation of organophosphates. It is interesting that the complex containing the ionic ligand efficiently degrades phosphorothioate pesticides, whereas complex N3 was not found to be appropriate for degradation due to a weaker conversion rate. The organophosphate degradation studies were monitored by recording absorbance spectra of parathion in the presence of catalyst, i.e., copper complexes with respect to time. The parathion was hydrolyzed into para-nitrophenol and diethyl thiophosphate. Moreover, to analyze the inhibition activity of the pesticides toward acetylcholine esterase enzyme in the presence of prepared metal complexes, Ellman's assay was performed and revealed that, within 20 min, the inhibition of acetylcholine esterase enzyme decreases by up to 13%.


Assuntos
Acetilcolina/metabolismo , Esterases/metabolismo , Estruturas Metalorgânicas/química , Praguicidas/química , Praguicidas/toxicidade , Fosfatos/química , Acetilcolina/análise , Benzimidazóis/química , Catálise , Cobre/química , Cristalografia por Raios X , Esterases/análise , Estruturas Metalorgânicas/síntese química , Modelos Moleculares , Estrutura Molecular , Fosfatos/toxicidade
6.
Toxicol Lett ; 313: 196-204, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31278966

RESUMO

Fipronil is a chiral insecticide employed worldwide in crops, control of public hygiene and control of veterinary pests. Humans can be exposed to fipronil through occupational, food, and environmental contamination. Therefore, the risk assessment of fipronil in humans is important to protect human health. Fipronil sulfone is the major metabolite formed during fipronil metabolism by humans. Since the CYP450 enzymes are the main ones involved in drug metabolism, the evaluation of their inhibition by fipronil and its main metabolite is important to predict drug-pesticide interactions. The aim of this work was to investigate the inhibition effects of rac-fipronil, S-fipronil, R-fipronil and fipronil sulfone on the main human CYP450 isoforms. The results showed that CYP2D6 is the only CYP450 isoform inhibited by these xenobiotics. In addition, no enantioselective differences were observed in the inhibition of CYP450 isoforms by fipronil and its individuals' enantiomers. Rac-fipronil, S-fipronil and R-fipronil are moderate CYP2D6 inhibitors showing a competitive inhibition profile. On the other hand, the metabolite fipronil sulfone showed to be a strong inhibitor of CYP2D6 also by competitive inhibition. These results highlight the importance of metabolite evaluation on pesticide safety since the metabolism of fipronil into fipronil sulfone increases the risk of pesticide-drug interactions for drugs metabolized by CYP2D6.


Assuntos
Inibidores do Citocromo P-450 CYP2D6/toxicidade , Citocromo P-450 CYP2D6/metabolismo , Praguicidas/toxicidade , Pirazóis/toxicidade , Citocromo P-450 CYP2D6/química , Inibidores do Citocromo P-450 CYP2D6/química , Relação Dose-Resposta a Droga , Interações de Medicamentos , Humanos , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Modelos Biológicos , Praguicidas/química , Conformação Proteica , Pirazóis/química , Medição de Risco , Relação Estrutura-Atividade
7.
Sci Total Environ ; 671: 466-473, 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-31331442

RESUMO

Removal of bio-accumulated pesticides in edible fish is a global problem. In this study, we tested protective capability of a phytochemical pelargonidin-loaded non-toxic, biodegradable poly-lactide-co-glycolide nano-particles (NPG) against toxicity induced by a pesticide cypermethrin (CM) in a fish model (Oreochromis mossambica) in vivo and also in L6 muscle cell line, in vitro. First we assessed potential sustainable release of nanoparticles following oral administration of NPG to fish, their ability to cross sub-cellular membranes in several tissues and efficacy to cross blood-brain-barrier. Next, protective ability of NPG, if any, against CM in fish was evaluated deploying parameters like % cell viability, DNA damage in muscle cells and modulation of anti-oxidative-enzymes like superoxide dismutase, catalase and lipid peroxidase. Modulation of reactive oxygen species generation, nuclear condensation and alteration in stress related protein signalling cascade were assessed in L6 cells. Results revealed that NPG had nano-size range (~10-12 nm) and negative zeta potential (-17 mV). Bioavailability and distribution of NPG could be followed by spectrophotometric absorbance of pelargonidin at 293 nm from 6 h onward till 24 h in all important tissues including the brain. Thus, 0.5 mg/g b.w. NPG could demonstrate protective ability in CM-intoxicated fish muscle cells in respect of % cell viability, DNA damage and stress related enzymes. Similar alterations could also be found in signalling protein cascade in L6 cells in response to treatment of 5 µg/ml NPG against CM-induced toxicity and depletion of overall ROS generation and nuclear condensation. Therefore, NPG could be used as a potential drug in management of pesticide toxicity in cultured edible fish.


Assuntos
Antocianinas/metabolismo , Antioxidantes/metabolismo , Ciclídeos/fisiologia , Praguicidas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Catalase/metabolismo , Dano ao DNA , Estresse Oxidativo , Transdução de Sinais , Superóxido Dismutase/metabolismo
8.
Medicine (Baltimore) ; 98(30): e16588, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31348299

RESUMO

Pesticide exposure is a major health risk factor among agricultural workers, and poor protective behavior and a lack of awareness concerning the risks of pesticide use in developing countries may increase the intensity of pesticide exposure. This cross-sectional study aimed to explore the relationship between neurologic symptoms and protective behavior and awareness in relation to pesticide use in China. Latent class cluster analysis was used to categorize participants into 3 latent cluster subgroups, namely, a poor protective behavior subgroup, an excellent protective awareness and behavior subgroup, and a poor protective awareness subgroup, using a person-centered approach. Multivariate regression models were used to detect the association between the latent class cluster subgroups and self-reported neurologic symptoms. The results showed that poor protective behavior in pesticide use was an important negative predicator of neurologic symptoms such as reduced sleep quality, frequency of nightmares, debility, hypopsia, and hypomnesis. These findings suggest that targeted interventions for agricultural workers, especially local greenhouse farmers, are urgently needed to improve pesticide protection behavior.


Assuntos
Doenças do Sistema Nervoso/induzido quimicamente , Doenças do Sistema Nervoso/prevenção & controle , Exposição Ocupacional/prevenção & controle , Praguicidas/toxicidade , Roupa de Proteção , Adulto , Doenças dos Trabalhadores Agrícolas/induzido quimicamente , Doenças dos Trabalhadores Agrícolas/prevenção & controle , China , Estudos Transversais , Fazendeiros , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Análise de Classes Latentes , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos
9.
Ecotoxicol Environ Saf ; 182: 109358, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31247395

RESUMO

Organochlorine pesticides (OCPs) are ubiquitous environmental contaminants, while their correlations with δ15N values and fatty acids (FAs) in fish tissues remain largely unexplored. In the present study, six species of fish for daily consumption were collected from Dongting Lake, and they were dissected to tissue samples to analyze the δ15N values, FAs and OCPs. The results showed that the δ15N values of fish were ranked in the same order in different fish tissues. The polyunsaturated fatty acids (PUFAs) had a different distribution pattern in fish tissues, while the saturated fatty acid (SFAs) and monounsaturated fatty acids (MUFAs) were not. The composition of HCHs in fish tissues exhibited a tissue-specific and species-specific manner, while such pattern was not detected for DDTs. The correlation analysis indicated that the ratio of DHA/EPA was increased with the increase of δ15N value in the muscle, liver, gill, skin and intestine, indicating the substance flow in freshwater ecosystem. In addition, there were significant positive correlations between the concentrations of some PUFAs and OCPs in the muscle, suggesting that people should pay attention to co-intake of OCPs when they supplemented the PUFAs needed by the human body through fish.


Assuntos
Ácidos Graxos/metabolismo , Hidrocarbonetos Clorados/metabolismo , Praguicidas/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , China , Correlação de Dados , Monitoramento Ambiental , Peixes , Humanos , Hidrocarbonetos Clorados/análise , Hidrocarbonetos Clorados/toxicidade , Lagos , Isótopos de Nitrogênio , Praguicidas/análise , Praguicidas/toxicidade , Alimentos Marinhos/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
10.
Ecotoxicol Environ Saf ; 181: 534-547, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31234068

RESUMO

Despite the increasing use of pesticides in tropical countries, research and legislative efforts have focused on their temperate counterparts. This paper presents a review of the literature on environmental risk assessment of pesticides for tropical terrestrial agroecosystems. It aims at evaluating potential differences in pesticide risk between temperate and tropical regions as well as to highlight research needs in the latter. Peculiarities of pesticide risks in tropical terrestrial agroecosystems are discussed in subsections 1) agricultural practices; 2) research efforts; 3) fate and exposure; 4) toxicity testing methods; and 5) sensitivity. The intensive and often inadequate pesticide application practices in tropical areas are likely to result in a relatively greater pesticide exposure in edge-of-field water bodies. Since pesticide fate may be different under tropical conditions, tropical scenarios for models estimating predicted environmental pesticide concentrations should be developed. Sensitivity comparisons do not indicate a consistent similar, greater or lower relative sensitivity of tropical soil organisms as compared to temperate organisms. However, several methods and procedures for application in the tropics need to be developed, which include: 1) identifying and collecting natural soils to be used as reference test substrates in tests; 2) identifying and discerning the range of sensitivity of native test species to soil contaminants; 3) developing test guidelines applicable to tropical/subtropical conditions; and 4) developing methods and procedures for higher tier testing for full development and implementation of environmental risk assessment schemes.


Assuntos
Ecossistema , Praguicidas/toxicidade , Poluentes do Solo/toxicidade , Testes de Toxicidade/normas , Clima Tropical , Agricultura , Biomarcadores Ambientais , Medição de Risco , Solo/química
11.
Chemosphere ; 231: 538-545, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31151014

RESUMO

Problems with pesticide residues in medicinal and edible plant have received great attention. The dietary exposure risk induced by presence of pesticide residues depends on its release from the food matrix, i.e., its bioaccessibility. The bioaccessibility of pesticide residues in human food is poorly understood and thus, we used in vitro digestive method to measure the bioaccessibility of six pesticides in Chaenomelis speciosa. Results showed that the lower and upper boundary bioaccessibility values of the six pesticides in C. speciosa was 4.26 and 86.52%, and the bioaccessibility varied for the pesticide types and digestion phase. The α-amylase and pancreatin play an important role in vitro bioaccessibility. Our findings suggest that risk assessment studies should be taken into account the pesticide metabolism, and that previous studies may have underestimated pesticide bioaccessibility.


Assuntos
Resíduos de Praguicidas/metabolismo , Praguicidas/metabolismo , Rosaceae/fisiologia , Disponibilidade Biológica , Humanos , Técnicas In Vitro , Resíduos de Praguicidas/química , Resíduos de Praguicidas/toxicidade , Praguicidas/toxicidade , Medição de Risco
12.
Environ Pollut ; 246: 876-884, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31159137

RESUMO

Ecotoxicological studies show the association between pesticide pollution and transgenerational toxicity in aquatic organisms. However, a less considered risk is that many pesticides can be metabolized and transferred to offspring as new toxicants. In this study, we used zebrafish to evaluate the maternal transfer risk of fipronil (FIP), which is a great threat to aquatic organisms with toxic metabolite formation. After 28-day exposure to environmentally relevant concentrations (1.0, 5.0 and 10.0 µg/L) of FIP in adult female zebrafish (F0), the toxicants off-loading and transgenerational toxicity in offspring were studied. High burdens of FIP and its sulfone metabolite were found in both F0 and the embryos (F1), resulting in increased CYP450 activity. The residual levels of the metabolite were higher than those of the parent compound. Chiral analysis further showed a preferential accumulation of S-enantiomer of FIP in both F0 and F1. Maternal exposure to FIP increased the malformation rate and decreased the swim speed in larvae. Additionally, after exposure, the levels of thyroid hormones (THs), including triiodothyronine (T3) and thyroxine (T4), decreased in both generations, particularly in the F1. Gene transcription expression along the hypothalamic-pituitary-thyroid (HPT) axis was also significantly affected. Maternal exposure to FIP increased sulfone metabolite enrichment and cause multiple toxic effects in F1. Findings from this study highlight the key role of biologically active product formation in the maternal transfer of pollutants and associated risk assessment.


Assuntos
Exposição Materna/efeitos adversos , Praguicidas/toxicidade , Pirazóis/toxicidade , Sulfonas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Disruptores Endócrinos/metabolismo , Disruptores Endócrinos/toxicidade , Feminino , Praguicidas/metabolismo , Pirazóis/metabolismo , Sulfonas/metabolismo , Hormônios Tireóideos/metabolismo , Poluentes Químicos da Água/metabolismo , Peixe-Zebra
13.
Chemosphere ; 232: 337-344, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31154195

RESUMO

In this study, we investigated the effects of three binary mixtures of pesticide formulations commonly used in soybean crop: Cypermethrin Atanor® (25% -CYP), Chlorpyrifos Lorsban 48E® (48% -CPF) and Glyphosate Roundup® Full II (66.2% -GLY) on broad-snouted caiman (Caiman latirostris) hatchlings exposed by voluntary immersion under controlled condition. Genotoxicity was evaluated in peripheral blood erythrocytes through the micronucleus (MN) test and other nuclear abnormalities (NAs) and besides, growth of caiman was analyzed in each experimental group. The results showed that pesticide formulations tested, at concentrations similar to those recommended for application in the field, induced an increase in the frequency of micronucleus (FMN; p = 0.001) and Notched nuclei (NN; p = 0.010) in the mixture CYP + CPF, while an increase in the frequency of buds and NN was observed in the mixture of GLY + CYP (pbuds = 0.016 and pNN = 0.021), compared to the vehicle control (VC). On the contrary, a possible antagonistic action was observed between the components in the mixture GLY + CPF. Growth was not affected in any exposed groups (p > 0.05). There was a clutch effect in the frequency of binucleated erythrocytes (BiN; p = 0.011), total length (TL; p = 0.001) and snout-vent length (SVL; p = 0.031). Biomarkers used in this study are considered important predictive tools for the evaluation of xenobiotics. In this study, we demonstrated genotoxicity of pesticide mixtures under conditions that simulate the real situation of exposure suffered by caiman and other wild species in Argentina.


Assuntos
Jacarés e Crocodilos/fisiologia , Testes para Micronúcleos , Mutagênicos/toxicidade , Praguicidas/toxicidade , Animais , Argentina , Clorpirifos/toxicidade , Dano ao DNA , Eritrócitos/efeitos dos fármacos , Glicina/análogos & derivados , Piretrinas/toxicidade
14.
Life Sci ; 231: 116585, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31226415

RESUMO

Exposure to environmental toxicants (ET) results in specific organ damage and auto-immune diseases, mostly mediated by inflammatory responses. The NLRP3 inflammasome has been found to be the major initiator of the associated pathologic inflammation. It has been found that ETs can trigger all the signals required for an NLRP3-mediated response. The exaggerated activation of the NLRP3 inflammasome and its end product IL-1ß, is responsible for the pathogenesis caused by many ETs including pesticides, organic pollutants, heavy metals, and crystalline compounds. Therefore, an extensive study of these chemicals and their mechanisms of inflammasome (INF) activation may provide the scientific evidence for possible targeting of this pathway by proposing possible protective agents that have been previously shown to affect INF compartments and its activation. Melatonin and polyunsaturated fatty acids (PUFA) are among the safest and the most studied of these agents, which affect a wide variety of cellular and physiological processes. These molecules have been shown to suppress the NLRP3 inflammasome mostly through the regulation of cellular redox status and the nuclear factor-κB (NF-κB) pathway, rendering them potential promising compounds to overcome ET-mediated organ damage. In the present review, we have made an effort to extensively review the ETs that exert their pathogenesis via the stimulation of inflammation, their precise mechanisms of action and the possible protective agents that could be potentially used to protect against such toxicants.


Assuntos
Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Animais , Ecotoxicologia/métodos , Poluentes Ambientais/toxicidade , Humanos , Inflamação/metabolismo , Inflamação/patologia , Interleucina-1beta/metabolismo , Melatonina/metabolismo , Metais Pesados/administração & dosagem , Metais Pesados/efeitos adversos , Metais Pesados/toxicidade , NF-kappa B/metabolismo , Oxirredução , Praguicidas/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
15.
Environ Sci Pollut Res Int ; 26(23): 24075-24087, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31228061

RESUMO

Knowledge regarding the concentration levels resulting from the use of agricultural pesticides may indicate the nature of the controls necessary to reduce environmental and human health risks to an acceptable level. Therefore, the main goal of the present work was to assess the spatial and temporal occurrence of 35 pesticides in the River Sado estuary (Portugal) in 2017 and evaluate its environmental condition, as data for estuarine ecosystems is scarce. Since pesticides are very susceptible to matrix effects promoted by environmental samples, to attain the main goal, we developed a fast and almost solvent-free environmentally friendly method with a good performance for both estuarine surface water and sediment samples. Quantified residues were determined mostly during summer, in line with the pesticide application period. Five herbicides (alachlor, bentazon, metobromuron, metribuzin and triclopyr) were measured in the water before and after the production season, suggesting a long-term aquatic exposure. Sediment samples were less contaminated, since a lower number of quantified pesticides were found in the study area, in lower frequencies and lower concentrations. No potential high adverse effects of the use of agricultural pesticides were expected on the aquatic organisms of the Sado estuary, even considering the potential combination effect of pesticide mixtures.


Assuntos
Estuários , Praguicidas/análise , Poluentes Químicos da Água/análise , Agricultura , Organismos Aquáticos , Cromatografia Líquida , Ecossistema , Ecotoxicologia/métodos , Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Humanos , Praguicidas/toxicidade , Portugal , Rios/química , Estações do Ano , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/toxicidade
16.
Environ Monit Assess ; 191(7): 454, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31222463

RESUMO

It is well-known that the metamorphosis process in amphibians is dependent on thyroid hormones. Laboratory studies have shown that several environmental contaminants can affect the function of thyroid hormones leading to alterations in the amphibian metamorphosis. The basic idea of the present study was to elucidate if the amphibian metamorphosis might be a useful tool as biomarker for effect-based environmental monitoring, examining wild tadpoles for potential thyroid hormone disruption. A laboratory test was performed to identify the responses from exposure to 6-propylthiouracil (PTU), which has a well-known mechanism on the thyroid system, on Swedish tadpoles from the Rana genus. This was followed by an environmental monitoring study where tadpoles of Rana arvalis, R. temporaria, and Bufo bufo were sampled from various sites in Sweden. Morphological data such as body weight, histopathological measurements of the thyroid glands, and environmental parameters were recorded. The results revealed that Rana tadpoles respond similar as other amphibians to PTU exposure, with interrupted development and increased size relative to the developmental stage. Data on some wild tadpoles showed similar features as the PTU exposed, such as high body weight, thus suggesting potential thyroid disrupting effects. However, histological evaluation of thyroid glands and pesticide analyses of the water revealed no clear evidence of chemical interactions. To a minor degree, the changes in body weight may be explained by natural circumstances such as pH, forest cover, and temperature. The present study cannot fully explain whether the high body weights recorded in some tadpoles have natural or chemical explanations. However, the study reveals that it is clearly achievable to catch tadpoles in suitable stages for the use in this type of biomonitoring and that the use of these biomarkers for assessment of thyroid disruption seems to be highly relevant.


Assuntos
Antitireóideos/toxicidade , Bufonidae/embriologia , Monitoramento Ambiental/métodos , Larva/crescimento & desenvolvimento , Praguicidas/toxicidade , Propiltiouracila/toxicidade , Ranidae/embriologia , Glândula Tireoide/patologia , Animais , Metamorfose Biológica , Suécia , Glândula Tireoide/efeitos dos fármacos , Hormônios Tireóideos/metabolismo
17.
Environ Sci Pollut Res Int ; 26(19): 19676-19683, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31079294

RESUMO

Since many different pesticides have been used occupationally, there have been inconsistent results regarding DNA damages among greenhouse workers. Thus, the aim of the study is to evaluate DNA damages, cell death, and chromosomal instability by using the buccal micronucleus cytome (BMcyt) assay in greenhouse workers and to compare those with a non-exposed group. The BMcyt assay was applied to the exfoliated buccal cell samples collected from 66 pesticide-exposed and 50 non-exposed individuals. We evaluated the frequency of micronucleus (MN), nuclear bud (NBUD), binucleated (BN) cells, and karyolitic (KL), pyknotic (PY), and karyorrhectic (KH) cells. The results showed that the MN, BN, PY, and KH frequencies of the pesticide-exposed group were significantly higher than those of the controls (P Ë‚ 0.05, P Ë‚ 0.05, P Ë‚ 0.01, and P Ë‚ 0.05, respectively). We observed that the MN, BN, PY, and KH frequencies in the autumn were statistically different compared with those in the control group (P = 0.037 for MN, P = 0.001 for BN, P = 0.016 for PY, and P = 0.033 for KH). The same comparison was done in the spring for the control, and there was a statistically significant difference for MN (P = 0.046) and PY (P = 0.014). We can conclude that pesticide exposure in greenhouse workers was one of the factors that altered DNA damages, cell death, and chromosomal instability in oral mucosa cells.


Assuntos
Instabilidade Cromossômica/efeitos dos fármacos , Dano ao DNA , Monitoramento Ambiental/métodos , Fazendeiros , Mucosa Bucal/efeitos dos fármacos , Exposição Ocupacional/análise , Praguicidas/toxicidade , Adulto , Morte Celular/efeitos dos fármacos , Feminino , Humanos , Masculino , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Testes para Micronúcleos , Mucosa Bucal/citologia , Exposição Ocupacional/efeitos adversos , Turquia
18.
Sci Total Environ ; 677: 57-67, 2019 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-31051383

RESUMO

Sustainable agriculture encourages practices that present low risks to the environment and human health. To this end, zein (corn protein) can be used to develop nanocarrier systems capable of improving the physicochemical properties of biopesticides, reducing their possible toxicity. Neem oil extracted from the Azadirachta indica tree contains many active ingredients including azadirachtin, which is the active ingredient in multiple commercially available biopesticides. In this study, we describe the preparation and characterization of neem oil-loaded zein nanoparticles, together with evaluation of their toxicity towards nontarget organisms, using Allium cepa, soil nitrogen cycle microbiota, and Caenorhabditis elegans aiming to achieve the safer by design strategy. The spherical nanoparticles showed an average diameter of 278 ±â€¯61.5 nm and a good stability during the experiments. In the toxicity assays with A. cepa, the neem oil-loaded zein nanoparticles mitigated the increase in the DNA relative damage index caused by the neem oil. Molecular genetic analysis of the soil nitrogen cycle microbiota revealed that neem oil-loaded zein nanoparticles did not change the number of genes which encode nitrogen-fixing enzymes and denitrifying enzymes. In C. elegans, the neem oil-loaded zein nanoparticles had no toxic effect, while neem oil interfered with pharyngeal pumping and GST-4 protein expression. These neem oil-loaded zein nanoparticles showed promising results in the toxicity studies, opening perspectives for its use in crop protection in organic agriculture.


Assuntos
Caenorhabditis elegans/efeitos dos fármacos , Glicerídeos/toxicidade , Microbiota/efeitos dos fármacos , Cebolas/efeitos dos fármacos , Praguicidas/toxicidade , Terpenos/toxicidade , Animais , Ecotoxicologia , Nanopartículas/toxicidade , Ciclo do Nitrogênio , Microbiologia do Solo , Testes de Toxicidade
19.
Chemosphere ; 230: 51-58, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31102871

RESUMO

Pesticide stress is one of the important factors for global bee declines. Apart from physiological and developmental anomalies, pesticides also impose cognitive damages on bees. The present study investigates the visual acuity of wild populations of honey bees, in an agricultural intensification landscape, and corroborates the findings with controlled laboratory experiments. Even though overall morphometric examinations revealed no significant differences between the populations, correct color choices by bees in pesticide exposed populations were significantly reduced. The study reports, for the first time, the significant reduction in ommatidia facet diameter in these populations, as viewed under scanning electron microscope, along with the molecular underpinnings to these findings. Western blot studies revealed a significant reduction in expression of two visual proteins - blue-sensitive opsin and rhodopsin - in the pesticide exposed populations in both field and laboratory conditions. The novel findings from this study form the basis for further investigations into the effects of field realistic doses of multiple pesticide exposures on wild populations of honey bees.


Assuntos
Abelhas/embriologia , Anormalidades do Olho/induzido quimicamente , Anormalidades do Olho/embriologia , Olho/embriologia , Praguicidas/toxicidade , Acuidade Visual/efeitos dos fármacos , Agricultura , Animais , Abelhas/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Opsinas/biossíntese , Rodopsina/biossíntese
20.
Chemosphere ; 230: 440-448, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31121508

RESUMO

Rice-crab (Chinese mitten crab, Eriocheir sinensis) coculture system has become one of the most important agricultural activities practiced in China. However, the effect of pesticide usage on the survival and edible safety of crab species living in the coculture system has not been investigated. In the present study, we created a field simulation experiment and discovered that the amount of pesticide chlorantraniliprole (CAP) entering the rice-crab coculture system accounted for 82.22% of the total CAP content present in the spray barrel. When CAP residues found in the soil leached into nearby areas, we observed an increase in the CAP concentration in the water and sediment. Specifically, peak CAP concentration (1.35 µg/L) was detected in water within 1 day, and a steady CAP concentration in the sediment (2.55 µg/kg) was detected within 3 days. Additionally, an extensive field sampling experiment conducted in the basin of the lower reaches of the Yangtze River revealed that CAP was routinely used in rice-crab coculture systems. Although detected CAP concentrations were below 1 µg/L in ditch water and below 1 µg/kg in ditch sediment, there was still a potential risk associated with the crab growth. Importantly, there was no risk associated with crab consumption, given the low detection frequency of CAP in the collected samples. Our analysis suggests that an increase in usage ratio and a decrease in the total CAP content will likely promote safe application of CAP in the rice-crab coculture systems.


Assuntos
Agricultura/métodos , Braquiúros/efeitos dos fármacos , Oryza/efeitos dos fármacos , Praguicidas/toxicidade , Rios/química , Poluentes Químicos da Água/toxicidade , ortoaminobenzoatos/toxicidade , Animais , Braquiúros/crescimento & desenvolvimento , China , Contaminação de Alimentos/análise , Oryza/crescimento & desenvolvimento , Praguicidas/análise , Medição de Risco , Alimentos Marinhos/análise , Poluentes Químicos da Água/análise , ortoaminobenzoatos/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA