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1.
SAR QSAR Environ Res ; 31(10): 785-801, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32878491

RESUMO

Reviewing the toxicological literature for over the past decades, the key elements of QSAR modelling have been the mechanisms of toxic action and chemical classes. As a result, it is often hard to design an acceptable single model for a particular endpoint without clustering compounds. The main aim here was to develop a Pass-Pass Quantitative Structure-Activity-Activity Relationship (PP QSAAR) model for direct prediction of the toxicity of a larger set of compounds, combing the application of an already predicted model for another species, and molecular descriptors. We investigated a large acute toxicity data set of five aquatic organisms, fish, Daphnia magna, and algae from the VEGA-Hub, as well as Tetrahymena pyriformis and Vibrio fischeri. The statistical quality of the models encouraged us to consider this alternative for the prediction of toxicity using interspecies extrapolation QSAAR models without regard to the toxicity mechanism or chemical class. In the case of algae, the use of activity values from a second species did not improve the models. This can be attributed to the weak interspecies relationships, due to different aquatic toxicity mechanisms in species.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Relação Quantitativa Estrutura-Atividade , Testes de Toxicidade Aguda , Poluentes Químicos da Água/toxicidade , Aliivibrio fischeri/efeitos dos fármacos , Animais , Daphnia/efeitos dos fármacos , Peixes , Regulamentação Governamental , Microalgas/efeitos dos fármacos , Modelos Químicos , Medição de Risco , Tetrahymena pyriformis/efeitos dos fármacos
2.
Bull Environ Contam Toxicol ; 105(4): 530-537, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32940716

RESUMO

An increase in the production and usage of gold nanoparticles (AuNPs) triggers the necessity to focus on their impact on ecosystems. Therefore, the purpose of this study was to investigate the acute toxicity of AuNPs and ionic gold (Au (III)) to organisms representing all trophic levels of the aquatic ecosystem, namely producers (duckweed Lemna minor), consumers (crustacean Daphnia magna, embryos of Danio rerio) and decomposers (bacteria Vibrio fischeri). The organisms were exposed according to a standardized protocol for each species and endpoints. The AuNPs (1.16 and 11.6 d.nm) were synthesized using citrate (CIT) and polyvinylpyrrolidone (PVP) as capping agents, respectively. It was found, that Au (III) was significantly more toxic than AuNPs PVP and AuNPs CIT. AuNPs showed significant toxicity only at high concentrations (mg/L), which are not environmentally relevant in the present time, but a cautious approach is advised, due to the possibility of interactions with other contaminants.


Assuntos
Aliivibrio fischeri/efeitos dos fármacos , Araceae/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Ouro/toxicidade , Íons/toxicidade , Nanopartículas Metálicas/toxicidade , Peixe-Zebra , Animais , Organismos Aquáticos , Daphnia/embriologia , Relação Dose-Resposta a Droga , Embrião não Mamífero/efeitos dos fármacos , Testes de Toxicidade Aguda
3.
Ecotoxicol Environ Saf ; 205: 111187, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32853869

RESUMO

Ionic liquids have been becoming new 'green solvent' because of the low saturation vapor pressure, less volatilization and more recycling utilization. Since most ILs are soluble in water, it should be indispensable to evaluate the ecotoxicology effect of ILs on aquatic environment before using them widely. Based on the concept of norm index, a set of norm descriptors were proposed for anions, cations and ILs. The whole IL structure optimization method has been used to build a predictive norm index-based quantitative structure-toxicity relationship model for the toxicity of ILs on Vibrio fischeri. Statistical results indicated that norm descriptors were reliable and robust in expressing the relationship between structural information and toxicity of ILs. Meanwhile, a series of ILs without experimental values were predicted based on this stable QSTR model. The results indicated that for imidazole-based ILs, an increase in the length of substituent in the branch could enhance the toxicity of ILs on Vibrio fischeri, and the branch contains hydroxyl group, double bond or triple bonds might reduce the toxicity of ILs. Results obtained in this present work would be valuable for the molecular design and the toxicity evaluation toward aquatic organism of ILs.


Assuntos
Aliivibrio fischeri/efeitos dos fármacos , Imidazóis , Líquidos Iônicos , Modelos Teóricos , Solventes , Ânions/química , Cátions/química , Ecotoxicologia/métodos , Imidazóis/química , Imidazóis/toxicidade , Líquidos Iônicos/química , Líquidos Iônicos/toxicidade , Valor Preditivo dos Testes , Relação Quantitativa Estrutura-Atividade , Solventes/química , Solventes/toxicidade
4.
Artigo em Inglês | MEDLINE | ID: mdl-32588236

RESUMO

High consumption of drugs, combined with their presence in the environment, raises concerns about its consequences. Even though researches are often engaged in analyzing substances separately, that is not the environmental reality. Therefore, the aim of this study was to investigate the acute toxicity of the pharmaceuticals simvastatin, metformin, omeprazole and diazepam, and all possible mixtures between them, to the organism Aliivibrio fischeri, verifying possible synergistic or antagonistic effects and assessing byproducts formation. In terms of individual toxicity, omeprazole is the most toxic of the active ingredients, followed by simvastatin, diazepam and, finally, metformin. When the toxicity of mixtures was tested, synergism, antagonism and hormesis were perceived, most probably generated due to byproducts formation. Moreover, it was observed that even when compounds are at concentrations below the non-observed effect concentration (NOEC), there may be toxicity to the mixture. Hence, this work points to the urgent need for more studies involving mixtures, since chemicals are subject to interactions and modifications, can mix, and potentiate or nullify the toxic effect of each other.


Assuntos
Aliivibrio fischeri/efeitos dos fármacos , Diazepam/toxicidade , Metformina/toxicidade , Omeprazol/toxicidade , Sinvastatina/toxicidade , Testes de Toxicidade Aguda
5.
Chemosphere ; 259: 127407, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32593821

RESUMO

The objective of this study was to investigate the impact of two pharmaceuticals, diclofenac and sulfamethoxazole, and their binary mixture on aquatic organisms, marine bacteria Aliivibrio fischeri, crustacean Daphnia magna, and vascular plant Lemna minor. The binary mixture of the drugs showed the highest toxicity towards the model organisms. Diclofenac had an average toxicity which posed a high environmental risk to aquatic organisms, while sulfamethoxazole was characterized by a low toxicity with low environmental risk. The organism most sensitive to diclofenac was A. fischeri (IC50 = 8.72 ± 1.14 mg L-1) and for sulfamethoxazole and the binary mixture, it was L. minor (IC50 = 12.56 ± 4.48 and 4.83 ± 0.43 mg L-1, respectively). The toxicity of the mixture was predicted using the Concentration Addition and Independent Action models, and the results were compared with the experimental data. None of the models suitably predicted the real toxicity of the pharmaceutical mixture. Interactions between the mixture components were confirmed by calculating the mixture toxicity index values which showed that the pharmaceuticals displayed synergistic or partial additive effects which depended on the selected test organism and test duration. When added as a complex matrix to wastewater (at a concentration of 2 mg L-1 each), the pharmaceuticals did not display increased toxicity. This observation confirms that the presence of micro-contaminants in aquatic environments may cause interactions between different compounds, the results of which are difficult to predict and model.


Assuntos
Diclofenaco/toxicidade , Sulfametoxazol/toxicidade , Poluentes Químicos da Água/toxicidade , Aliivibrio fischeri/efeitos dos fármacos , Animais , Organismos Aquáticos , Araceae/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Águas Residuárias , Poluentes Químicos da Água/análise
6.
Artigo em Inglês | MEDLINE | ID: mdl-32291616

RESUMO

Sodium lauryl ether sulphate (SLES) is the main chemical component in several lubricant products used for soil conditioning in the mechanized excavation industry using Earth Pressure Balance-Tunnel Boring Machines. During the tunnelling process, huge amounts of excavated soil are produced and the SLES presence can affect the subsequent re-use of this material as a by-product. Currently, there is still no regulatory indication of reliable and sensitive bioassays for monitoring soil quality during the excavation process. The main objective of this work was to verify if the Vibrio fischeri screening test was suitable as a consistent and precautionary tool for this specific purpose. Firstly, the ecotoxicity (EC20 and EC50) of the SLES standard solution and three commercial products (SLES content from 10 to 50%) were evaluated to select the most environmental friendly product. Subsequently, soil samples from about 2 years of tunnelling in a real construction site, conditioned with the selected product, were evaluated for their environmental compatibility with the prescriptions of an Italian site-specific protocol. The latter established 2 mg/L as a threshold value for SLES concentration in soil water extracts and a no toxic response (≤20%) for the Vibrio fischeri test. The comparison of the bacterium bioluminescence inhibition values (%) with analytical determinations showed an ecotoxicity when SLES was >2 mg/L. The toxicity was directly related to SLES concentration, indicating that the V. fischeri test and the SLES analyses are suitable tools for assessing excavated soil as a by-product, ensuring its safe reuse in accordance with a green production process (circular economy).


Assuntos
Aliivibrio fischeri/efeitos dos fármacos , Éteres/toxicidade , Dodecilsulfato de Sódio/toxicidade , Poluentes do Solo/toxicidade , Solo/química , Itália , Testes de Toxicidade Aguda
7.
Luminescence ; 35(3): 434-436, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32239641

RESUMO

The antibacterial properties of self-cleaning coatings are based on bactericide nanoparticles (NPs). Ecotoxicity of these NPs have been assessed mostly in suspension, using standard bioassays. Here a protocol is proposed to test actual coating samples, using the Vibrio fischeri bioluminescence inhibition bioassay. The protocol was designed to test bactericide properties of specially coated PVC floors being used in hospital environments under quasinatural conditions, such as prolonged exposure or room temperature. To take into consideration that the light output of the bacteria under prolonged exposure naturally changes, a correction factor is proposed.


Assuntos
Aliivibrio fischeri/efeitos dos fármacos , Antibacterianos/farmacologia , Nanopartículas/química , Antibacterianos/química , Medições Luminescentes , Testes de Sensibilidade Microbiana
8.
Ecotoxicol Environ Saf ; 194: 110331, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32146199

RESUMO

In this paper, comparison of ecotoxicological and herbicidal effect of newly synthesized N­[(phosphono)(aryl)methyl]glycines 1a-g (C-substituted glyphosate derivatives) with pure glyphosate (N-phosphonomethylglycine) (2) was demonstrated. All of tested glyphosate derivatives (1a-g) in contrast to glyphosate, were found to be completely safe for oat (Avena sativa) and classified as not harmful for marine bacteria Aliivibrio fischeri. Compounds 1a-g were also found rather harmless to radish (Raphanus sativus) as compared to N-phosphonomethylglycine, but they were moderately toxic against freshwater crustaceans Heterocypris incongruens. One of synthesized compounds, namely N-[(phosphono)(4-hydroxyphenyl)methyl]glycine (1f) was found to possess stronger herbicidal properties against gallant soldier (Galinsoga parviflora) and common sorrel (Rumex acetosa) when compared to pure glyphosate and demonstrated total death of these weeds being ranked 1 in the European Weed Research Council (EWRC) scale. Considering lower phytotoxicity of compound 1f against cultivated plants and tested microorganisms when compared to pure glyphosate, this aminophosphonate may be good candidate for further, more comprehensive study toward its agrochemical application, especially that this active agent demonstrated much stronger herbicidal properties than N-phosphonomethylglycine.


Assuntos
Ecotoxicologia , Glicina/análogos & derivados , Herbicidas/toxicidade , Agricultura , Aliivibrio fischeri/efeitos dos fármacos , Animais , Avena/efeitos dos fármacos , Crustáceos/efeitos dos fármacos , Glicina/toxicidade , Herbicidas/química , Plantas Daninhas/efeitos dos fármacos , Raphanus/efeitos dos fármacos , Testes de Toxicidade
9.
Chemosphere ; 248: 126085, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32041071

RESUMO

Hormesis is an ecotoxicological phenomenon referred to as the biphasic dose-response effect. At a low concentration of toxic substances, a hormetic stimulating effect occurs, while an inhibitory effect occurs at higher concentrations. The phenomenon of hormesis may hinder the interpretation of toxicity test results and lower the actual toxicity of test samples. In this study, a hormesis phenomenon was observed and analysed during toxicity tests of wastewater from constructed wetlands containing two pharmaceutical substances, diclofenac (DCF) and sulfamethoxazole (SMX), against the marine bacteria Aliivibrio fischeri. To eliminate the hormesis phenomenon, a change in the diluent (ISO 11348-3:2007) to synthetic sea water (ISO 10253:2006) is proposed. The hormesis phenomenon was observed only during the analysis of wastewater toxicity with the standard toxicity test (with the diluent). The use of synthetic sea water eliminated the hormetic effects because of the presence of additional components in the sea water, such as MgCl2, Na2SO4, CaCl2, KCl, NaHCO3, and H3BO3, which increased the sensitivity of A. fischeri to the pharmaceutical substances. The use of different media in toxicity tests may have significant effects on the toxicity classification of the tested compounds or wastewater. Additionally, the toxicity of tested pharmaceuticals towards A. fischeri was analysed. The IC50 values of DCF were 8.7 ± 1.1 mg L-1 (for diluent) and 13.9 ± 0.9 mg L-1 (for synthetic sea water) whereas those of SMX were 50.5 ± 2.3 and 55.3 ± 1.6 mg L-1, respectively.


Assuntos
Aliivibrio fischeri/efeitos dos fármacos , Hormese/efeitos dos fármacos , Água do Mar/química , Testes de Toxicidade/métodos , Diclofenaco/toxicidade , Ecotoxicologia , Sulfametoxazol/toxicidade , Águas Residuárias/química , Poluentes Químicos da Água/toxicidade
10.
Chemosphere ; 248: 126040, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32041066

RESUMO

Acetamiprid is a neonicotinoid pesticide, which is extensively used on agricultural crops, but has a high toxic effect on beneficial insects and the human body. It is exposed to sunlight irradiation on crops but also in surface waters where it is found at a high level due to its resistance to common water treatments. The aim of the present work was to study the UV-visible photodegradation of acetamiprid, alone and in two marketed mixtures (Polysect Ultra SL® and Roseclear Ultra®). Ten photoproducts were characterized using LC-HR-MS/MS analysis. Photodegradation pathways were proposed based on the chemical structures of photoproducts and kinetic measurements; a matrix effect has been evidenced for commercial mixtures. Most photoproducts exhibit potential developmental toxicity twice higher than that of the parent compound. Regarding potential mutagenicity, all photoproducts are less toxic than acetamiprid. Estimated oral rat LD50 values show that the potential toxicities of photoproducts are similar or lower than that of acetamiprid. In vitro tests on Vibrio fischeri bacteria showed that the ecotoxicities of marketed mixtures are significantly higher than that of acetamiprid in aqueous solution; they slightly increase after UV-light exposure.


Assuntos
Inseticidas/química , Neonicotinoides/química , Raios Ultravioleta , Aliivibrio fischeri/efeitos dos fármacos , Animais , Cromatografia Líquida , Humanos , Inseticidas/toxicidade , Cinética , Mutagênicos , Processos Fotoquímicos , Fotólise , Ratos , Luz Solar , Espectrometria de Massas em Tandem
11.
Ecotoxicol Environ Saf ; 192: 110207, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32032860

RESUMO

Many studies have been conducted on the evaluation and monitoring of micropollutants and by-products in wastewater treatment plants. Considering the increase in the production and consumption of emerging contaminants, such as drugs, personal care products, and plasticisers, it is necessary to conduct studies that support the elaboration of laws and regulations that promote the environmentally sustainable use of sludge and effluents. In this work, the biological degradation of amoxicillin was studied under two anaerobic conditions: i) using a 6 L reactor operated under semi-continuous flow; and ii) a batch system with 100 mL sealed glass syringes. According to the statistical analysis, amoxicillin was completely removed from the systems, but biogas production inhibition was observed (p < 0.05). Liquid chromatography-high-resolution mass spectrometry analysis identified amoxicillin penicilloic acid, amoxilloic acid, amoxicillin diketopiperazine and phenol hydroxypyrazine as by-products under anaerobic conditions. Ecotoxicity tests on effluent treated under the batch conditions showed that the addition of higher amounts of amoxicillin inhibited the target species Aliivibrio fischeri and Raphidocelis subcaptata, causing functional decreases of 28.5% and 22.2% when the antibiotic concentration was 2500 µg L-1. A. fischeri was the most sensitive organism to effluent treated under semi-continuous flow conditions; a continuous reduction in bioluminescence of up to 88.8% was observed after 39 days of feeding, which was associated with by-products accumulation due to unbalanced conditions during anaerobic digestion. Changes in the physico-chemical characteristics of the effluent caused the accumulation and removal of AMX-DKP IV and modified the toxicity to Lactuca sativa and R. subcapitata.


Assuntos
Amoxicilina/metabolismo , Antibacterianos/metabolismo , Águas Residuárias/química , Poluentes Químicos da Água/metabolismo , Aliivibrio fischeri/efeitos dos fármacos , Amoxicilina/toxicidade , Anaerobiose , Antibacterianos/toxicidade , Biocombustíveis/análise , Ecotoxicologia , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/toxicidade
12.
Aquat Toxicol ; 220: 105417, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31958710

RESUMO

Pyraclostrobin is a fungicide used widely across the world. However, its photolysis pathway and toxic mechanism is unclear. In this study, photolysis and photo-induced toxicity of pyraclostrobin to Vibrio fischeri were determined. The results showed that direct photolysis dominated the degradation of pyraclostrobin. Gas Chromatography-Mass spectrometry and quantum chemical calculation revealed that the pyraclostrobin was firstly photo-degraded into Methyl N-phenyl-carbamate and 1-(4-chlorophenyl)-3-hydroxy-1H-pyrzole, synthetic intermediates of pyraclostrobin, then into aniline, benzoquinone and acids. Toxicity assay showed that bioluminescent inhibition rate to V. fischeri fluctuated with radiation/illumination time and the toxicity curve can be classified into three phases (Phase I: 0-10 min, incline; Phase II: 10-60 min, decline; Phase III: 60-120 min, incline). The up-and-down curve indicates the change of parent compound during the photolysis. Simulation of molecular docking showed that the CDOCKER interaction energy of pyraclostrobin (-44.71) lower than other intermediate products (>-30.00), indicating that the parent compound is more toxic than its intermediates. An increased toxicity observed in the toxicity curve was attributed to the generation of benzoquinone with log1/EC50 of 6.73, which can greatly change structure of target luciferase in Vibrio fischeri. In addition, the addition of radical scavengers can inhibit the bioluminescence of the tested solutions, indicating the involvement of radicals in the transformation of intermediates. This paper reveals that one of photochemical transformation products of pyraclostrobin can cause more toxic than its parent compound to bacteria. Environmental risk assessment should consider not only the parent compound, but also its metabolites.


Assuntos
Aliivibrio fischeri/efeitos dos fármacos , Fungicidas Industriais/toxicidade , Fotólise/efeitos dos fármacos , Estrobilurinas/toxicidade , Poluentes Químicos da Água/toxicidade , Simulação por Computador , Relação Dose-Resposta a Droga , Fungicidas Industriais/efeitos da radiação , Cromatografia Gasosa-Espectrometria de Massas , Simulação de Acoplamento Molecular , Estrobilurinas/efeitos da radiação , Poluentes Químicos da Água/efeitos da radiação
13.
Arch Environ Contam Toxicol ; 78(4): 545-554, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31915850

RESUMO

Chemicals pollution in the environment has attracted attention all over the world, and the toxicity prediction of chemical pollutants has become quite important. In this paper, we introduce a simple approach to predict the toxicity of some chemical components, in which the Tchebichef image moment (TM) method was employed to extract useful chemical information from the images of molecular structures to establish quantitative structure-activity relationship (QSAR) prediction models. The proposed approach was applied to predict the toxicity of anilines and phenols for the aquatic organisms of P. subcapitata and V. fischeri, in which the obtained TMs were defined as the independent variables, while the biological toxicity (pEC50) was regarded to be the dependent variable. Then, the predictive models were established by stepwise regression, respectively. The obtained squared correlation coefficients of leave-one-out cross-validation (Q2) for training sets and the predictive squared correlation coefficients (Rp2) for test sets of the two groups of data were higher than 0.79 and 0.75, respectively, which indicated that the obtained models possessed satisfactory accuracy and reliability. Compared with several reported methods, the proposed approach was more convenient and has a higher predictive capability. Our study provides another perspective in QSAR research.


Assuntos
Compostos de Anilina/toxicidade , Organismos Aquáticos/efeitos dos fármacos , Modelos Teóricos , Fenóis/toxicidade , Poluentes Químicos da Água/toxicidade , Aliivibrio fischeri/efeitos dos fármacos , Compostos de Anilina/química , Clorófitas/efeitos dos fármacos , Fenóis/química , Valor Preditivo dos Testes , Relação Quantitativa Estrutura-Atividade , Reprodutibilidade dos Testes , Poluentes Químicos da Água/química
14.
Int J Mol Sci ; 21(2)2020 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-31940888

RESUMO

Hormesis is a concentration-response phenomenon characterized by low-concentration stimulation and high-concentration inhibition, which typically has a nonmonotonic J-shaped concentration-response curve (J-CRC). The concentration addition (CA) model is the gold standard for studying mixture toxicity. However, the CA model had the predictive blind zone (PBZ) for mixture J-CRC. To solve the PBZ problem, we proposed a segmented concentration addition (SCA) method to predict mixture J-CRC, which was achieved through fitting the left and right segments of component J-CRC and performing CA prediction subsequently. We selected two model compounds including chlortetracycline hydrochloride (CTCC) and oxytetracycline hydrochloride (OTCC), both of which presented J-CRC to Aliivibrio fischeri (AVF). The seven binary mixtures (M1-M7) of CTCC and OTCC were designed according to their molar ratios of 12:1, 10:3, 8:5, 1:1, 5:8, 3:10, and 1:12 referring to the direct equipartition ray design. These seven mixtures all presented J-CRC to AVF. Based on the SCA method, we obtained mixture maximum stimulatory effect concentration (ECm) and maximum stimulatory effect (Em) predicted by SCA, both of which were not available for the CA model. The toxicity interactions of these mixtures were systematically evaluated by using a comprehensive approach, including the co-toxicity coefficient integrated with confidence interval method (CTCICI), CRC, and isobole analysis. The results showed that the interaction types were additive and antagonistic action, without synergistic action. In addition, we proposed the cross point (CP) hypothesis for toxic interactive mixtures presenting J-CRC, that there was generally a CP between mixture observed J-CRC and CA predicted J-CRC; the relative positions of observed and predicted CRCs on either side of the CP would exchange, but the toxic interaction type of mixtures remained unchanged. The CP hypothesis needs to be verified by more mixtures, especially those with synergism. In conclusion, the SCA method is expected to have important theoretical and practical significance for mixture hormesis.


Assuntos
Aliivibrio fischeri/efeitos dos fármacos , Clortetraciclina/farmacologia , Composição de Medicamentos/métodos , Oxitetraciclina/farmacologia , Clortetraciclina/efeitos adversos , Combinação de Medicamentos , Hormese , Viabilidade Microbiana/efeitos dos fármacos , Modelos Químicos , Oxitetraciclina/efeitos adversos , Testes de Toxicidade
15.
Ecotoxicol Environ Saf ; 191: 110203, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31972453

RESUMO

The aim of this study was to evaluate of possibility of biotransformation and toxicity effect of monoanthraquinone dyes in cultures of Bjerkandera adusta CCBAS 930. Phenolic compounds, free radicals, phytotoxicity (Lepidium sativum L.), ecotoxicity (Vibrio fischeri) and cytotoxicity effect were evaluated to determine the toxicity of anthraquinone dyes before and after the treatment with B. adusta CCBAS 930. More than 80% of ABBB and AB129 was removed by biodegradation (decolorization) and biosorption, but biodegradation using oxidoreductases was the main dye removing mechanism. Secondary products toxic to plants and bacteria were formed in B. adusta strain CCBAS 930 cultures, despite efficient decolorization. ABBB and AB129 metabolites increased reactive oxygen species (ROS) production in human fibroblasts, but did not increase LDH release, did not affect the resazurine reduction assay and did not change caspase-9 or caspase-3 activity.


Assuntos
Antraquinonas/metabolismo , Antraquinonas/toxicidade , Corantes/metabolismo , Corantes/toxicidade , Coriolaceae/metabolismo , Aliivibrio fischeri/efeitos dos fármacos , Biodegradação Ambiental , Biotransformação , Corantes/química , Humanos , Lepidium sativum/efeitos dos fármacos , Fenóis/análise
16.
Ecotoxicol Environ Saf ; 191: 110004, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31810589

RESUMO

(Eco)toxicological information of natural deep eutectic solvents (NADES) is scarce, and thus, quantitative structure activity relationship (QSAR) models are an important tool for achieving the prediction of toxicity in this case. For that reason, in this manuscript, a new QSAR model for predicting the ecotoxicity of NADES towards the Aliivibrio fischeri biomodel, using mixing rules, is proposed. The main advantage of the method is that the individual components of the mixtures are molecularly modelled, and then, a mixing rule is used, which simplifies the process. For developing the model, a total of 11 descriptors for each component is used: the dissociation constant, partition coefficient, Van der Waals volume, Van der Waals surface area, topological polar surface area, solvent accessible surface area, minimum projection area, maximum projection area, minimum projection radius, maximum projection radius and molecular weight. The final obtained model includes the topological polar surface area and the dissociation constant, mechanistically interpreted as the ability of a NADES to transport through biological membranes and the severe negative effect of pH on the toxicity and biological response of Aliivibrio fischeri bacteria. The OECD Guidance Document on the Validation of (Quantitative) Structure-Activity Relationships is followed to develop the mathematical model.


Assuntos
Aliivibrio fischeri/efeitos dos fármacos , Solventes/toxicidade , Modelos Moleculares , Relação Quantitativa Estrutura-Atividade , Solventes/química
17.
J Environ Sci Health B ; 55(3): 257-264, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31680628

RESUMO

The Parati River contributes to the Babitonga Bay water complex, but the contents of the bay also influence the river during periods of inverted currents. In this study, the water quality along four stretches of the Parati River and Babitonga Bay was evaluated using chemical (physico-chemical and chromatographic analysis), microbiological (fluorescein diacetate hydrolysis) and ecotoxicological (Lumistox) methods to assess the reciprocal influence of the waters of this river-bay system. In addition, the most appropriate type of analysis for the monitoring of the estuarine region of the Parati River was identified. The results of six sampling campaigns showed that the type of contaminants and their levels varied temporally and spatially and thus the water quality also changed. Anthropogenic activity, such as banana cultivation and the release of sewage into the water system, is the primary cause of the contamination that affects the quality of the water in the Parati River estuary, which is a crucial ecological niche for the reproduction of various marine species. The ecotoxicity tests with Aliivibrio fischeri conducted to evaluate the water quality showed an integrative response, and the ecotoxicity data indicated that the Parati River does not have a significant influence on the water quality of Babitonga Bay.


Assuntos
Baías/química , Rios/química , Poluentes Químicos da Água/análise , Qualidade da Água , Aliivibrio fischeri/efeitos dos fármacos , Baías/microbiologia , Brasil , Ecossistema , Ecotoxicologia/métodos , Monitoramento Ambiental/métodos , Estuários , Praguicidas/análise , Rios/microbiologia , Esgotos
18.
Chemosphere ; 241: 125111, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31683437

RESUMO

Linezolid (LIN) and Tedizolid (TED) are representatives of oxazolidinone antibiotics of last resort with a strong efficacy against gram-positive bacteria. This study focused on their solar-mediated degradation to understand better their fate in aquatic environment, for the realistic concentrations in the range of 1 µg/L. Results showed that both antibiotics (ABs) are degradable by simulated sunlight (1 kW/m2), with half-lives of 32 and 93 h in ultrapure water, for LIN and TED, respectively. LIN showed similar photolytic behaviour in pure solution and in surface water, whereas sunlight enhanced the degradation of LIN in pure solutions, but not in surface water. Structure elucidation by liquid chromatography coupled to high resolution mass spectrometry provided information about seven transformation products for LIN and five for TED. The morpholinyl-ring was identified as the target site for most transformation reactions of LIN. TED was prone to oxidation and cleavage of the oxazolidinone ring. Results of a growth inhibition test on Bacillus subtilis exposed to UV light showed antibacterial efficacy of transformation products of LIN and no significant efficacy of degradation products of TED for the concentration range of 100 µg/L-10 mg/L of parent compounds. Photolytically treated solutions of the ABs maintained their inhibitory effect on the bioluminescence of Aliivibrio fischeri.


Assuntos
Antibacterianos/química , Linezolida/química , Oxazolidinonas/química , Fotólise/efeitos da radiação , Luz Solar , Tetrazóis/química , Poluentes Químicos da Água/química , Aliivibrio fischeri/efeitos dos fármacos , Bacillus subtilis/efeitos dos fármacos , Recuperação e Remediação Ambiental/métodos , Cinética , Estrutura Molecular , Poluentes Químicos da Água/análise
19.
Artigo em Inglês | MEDLINE | ID: mdl-31607225

RESUMO

III-V semiconductor materials such as gallium arsenide (GaAs) and indium arsenide (InAs) are increasingly used in the fabrication of electronic devices. There is a growing concern about the potential release of these materials into the environment leading to effects on public and environmental health. The waste effluents from the chemical mechanical planarization process could impact microorganisms in biological wastewater treatment systems. Currently, there is only limited information about the inhibition of gallium- and indium-based nanoparticles (NPs) on microorganisms. This study evaluated the acute toxicity of GaAs, InAs, gallium oxide (Ga2O3), and indium oxide (In2O3) particulates using two microbial inhibition assays targeting methanogenic archaea and the marine bacterium, Aliivibrio fischeri. GaAs and InAs NPs were acutely toxic towards these microorganisms; Ga2O3 and In2O3 NPs were not. The toxic effect was mainly due to the release of soluble arsenic species and it increased with decreasing particle size and with increasing time due to the progressive corrosion of the NPs in the aqueous bioassay medium. Collectively, the results indicate that the toxicity exerted by the arsenide NPs under environmental conditions will vary depending on intrinsic properties of the material such as particle size as well as on the dissolution time and aqueous chemistry.


Assuntos
Aliivibrio fischeri/efeitos dos fármacos , Gálio/toxicidade , Índio/toxicidade , Nanopartículas/toxicidade , Poluentes Químicos da Água/toxicidade , Aliivibrio fischeri/metabolismo , Arsenicais/química , Gálio/química , Índio/química , Metano/biossíntese , Nanopartículas/química , Tamanho da Partícula , Semicondutores , Esgotos/microbiologia , Propriedades de Superfície , Poluentes Químicos da Água/química , Purificação da Água/métodos
20.
Chemosphere ; 240: 124947, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31568943

RESUMO

This work studies the effect of the cation and anion on the biodegradability and inhibition of imidazolium- and choline-based ionic liquids (ILs) using activated sludge. Six commercial ILs, formed by combination of 1-Butyl-3-methylimidazolium (Bmim+) and N,N,N-trimethylethanolammonium (Choline+) cations and chloride (Cl-), acetate (Ac-) and bis(trifluoromethanesulfonyl)imide (NTf2-) anions were evaluated, all representative counter-ions with markedly different toxicity and biodegradability. Inherent and fast biodegradability tests were used to evaluate both the microorganism inhibition and the IL biodegradability. In addition, the ecotoxicological response (EC50) of the ILs was studied using activated sludge and Vibrio fischeri (Microtox® test). Bmim+ and NTf2- can be considered as non-biodegradable, whereas aerobic microorganisms easily degraded Choline+ and Ac-. The biodegradation pattern of each cation/anion is nearly unaffected by counter-ion nature. Moreover, concentrations of CholineNTf2 higher than 50 mg/L caused a partial inhibition on microbial activity, in good concordance with its low EC50 (54 mg/L) measured by respiration inhibition test, which alerts on the negative environmental impact of NTf2-containing ILs on the performance of sewage treatment plants.


Assuntos
Aliivibrio fischeri/efeitos dos fármacos , Biodegradação Ambiental , Colina/análise , Hidrocarbonetos Fluorados/química , Imidazóis/análise , Imidazóis/química , Imidas/química , Compostos de Amônio Quaternário/química , Ecotoxicologia , Líquidos Iônicos/análise , Esgotos/química , Purificação da Água/métodos
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