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1.
Artigo em Inglês | MEDLINE | ID: mdl-33563085

RESUMO

The objective of this study was to investigate 13 phthalic acid esters (PAEs) with medium or long straight-alkyl-chain, branching or unsaturated side chains, because their structural characteristics make them difficult to biodegrade or highly toxic. A biodegradability and biotoxicity multi-effect pharmacophore model was built using comprehensive evaluation method. The results suggested that introducing hydrophobic groups to the side chains of the PAEs could improve the molecules' biodegradability and biotoxicity effects simultaneously. Thus, 40 target PAE (HEHP, DNOP, DUP) derivatives were designed. Two environmentally friendly PAE derivatives (HEHP-Anthryl and HEHP-Naphthyl) were screened via the test of environmental friendliness and functionality. In addition, the biodegradation and biotoxicity of derivatives were found to have improved as a result of the change in van der Waals forces between molecules and their corresponding proteins. Moreover, the environmental safety of the screened PAE derivatives was confirmed by predicting the toxicity of their intermediates and calculating the energy barrier values for biodegradation and metabolic pathways. This study could provide theoretical guidance for the practical development of environmentally friendly plasticizer.


Assuntos
Ésteres , Modelos Teóricos , Ácidos Ftálicos , Plastificantes , Animais , Biodegradação Ambiental , Decápodes/efeitos dos fármacos , Ésteres/química , Ésteres/metabolismo , Ésteres/toxicidade , Interações Hidrofóbicas e Hidrofílicas , Ácidos Ftálicos/química , Ácidos Ftálicos/metabolismo , Ácidos Ftálicos/toxicidade , Plastificantes/química , Plastificantes/metabolismo , Plastificantes/toxicidade
2.
Food Chem ; 348: 129065, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33493846

RESUMO

Cultivated mushrooms inevitably absorb phthalate esters (PAEs) and potentially toxic metal(loid)s from plastic grow bags and substrate. The associated harm to consumers should be further clarified. This study measured six priority PAEs and nine metal(loid)s in eight mushroom varieties from greenhouses near Jingmen, Hubei, central China. The averaged total target PAE was between 8.60 ± 1.55 and 27.20 ± 5.90 mg kg-1 dry weight. Levels of di-n-butyl phthalate in all samples and those of di-(2-ethylhexyl) phthalate in four mushroom species exceeded the maximum residual amount of China. Compared with the maximum levels of contaminants for foods in China, Cd in one and Pb in four mushroom species exceeded the limits. The estimated weekly intake of As, Cd, Cu, Hg, and Pb for different age groups was higher than the provisional tolerable weekly intake; however, there was no significant carcinogenic risks based on assessment of single or combined PAEs and metal(loid)s.


Assuntos
Ésteres/química , Contaminação de Alimentos/análise , Fungos/química , Metais Pesados/análise , Ácidos Ftálicos/análise , Ácidos Ftálicos/química , China , Fungos/crescimento & desenvolvimento , Medição de Risco
3.
Ecotoxicol Environ Saf ; 208: 111624, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396144

RESUMO

Phthalate esters (PAEs), such as dibutyl phthalate (DBP) and di-(2-ethylhexyl) phthalate (DEHP), are used extensively as additives and plasticizers, and have become ubiquitous in the environment. PAEs in the soil could have adverse effects on crop plants as well as humans via accumulations in food chain. Thus, it is important to explore strategies to reduce the bioavailability of phthalate esters. We investigated the effects of Fe-Mn oxide-modified biochar composite (FMBC) applications on the quality of wheat grown in DBP- and DEHP-polluted brown soil. The application of FMBC and biochar (BC) increased the wheat grain biomass by 9.71-223.01% and 5.40-120.15% in the DBP-polluted soil, and 10.52-186.21% and 4.50-99.53% in the DEHP-spiked soil in comparison to the controls. All FMBC treatments were better than the BC treatments, in terms of decreasing DBP and DEHP bioavailability for the wheat grains. The activities of the glutamine synthetase and glutamic-pyruvic transaminase in the flag leaves at the filling stage and of granule-bound starch synthase, soluble starch synthase, and adenosine diphosphate-glucose pyrophosphorylase in the grains at maturity increased significantly with increases in either the BC or FMBC applications. This, in turn, increased the starch, protein, and amino acid content in the wheat grains. Compared with the BC treatment, the FMBC amendment induced only slight increases in the aforementioned factors. This study offers novel insights into potential strategies for decreasing PAEs bioavailability in soil, with potential positive implications for crop quality and environmental health improvements.


Assuntos
Carvão Vegetal/química , Recuperação e Remediação Ambiental/métodos , Ácidos Ftálicos/química , Poluentes do Solo/metabolismo , Triticum/fisiologia , Dibutilftalato/análise , Dibutilftalato/metabolismo , Dietilexilftalato/metabolismo , Grão Comestível/química , Poluição Ambiental , Ésteres/análise , Humanos , Ferro/análise , Óxidos/análise , Plastificantes/análise , Solo/química , Poluentes do Solo/análise , Triticum/metabolismo
4.
ACS Appl Mater Interfaces ; 13(3): 4146-4155, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33440928

RESUMO

Immobilization can be used to improve the stability of lipases and enhances lipase recovery and reusability, which increases its commercial value and industrial applications. Nevertheless, immobilization frequently causes conformational changes of the lipases, which decrease lipase catalytic activity. in the present work, we synthesized UIO-66 and grafted UIO-66 crystals with proline for immobilization of Candida rugosa lipase (CRL). As indicated by steady-state fluorescence microscopy, grafting of proline onto UIO-66 crystals induced beneficial conformational change in CRL. CRL immobilized on UIO-66/Pro (CRL@UIO-66/Pro) demonstrated higher enzyme activity and better recyclability than that immobilized on UIO-66 (CRL@UIO-66) in both hydrolysis (CRL@UIO-66/Pro: 0.34 U; CRL@UIO-66: 0.15 U) and transesterification (CRL@UIO-66/Pro: 0.93 U; CRL@UIO-66: 0.25 U) reactions. The higher values of kcat and kcat/Km of CRL@UIO-66/Pro also showed that it had better catalytic efficiency as compared to CRL@UIO-66. It is also worth noting that CRL@UIO-66/Pro (0.93 U) demonstrated a much higher transesterification activity as compared to free CRL (0.11 U), indicating that UIO-66/Pro has increased the solvent stability of CRL. Both CRL@UIO-66 and CRL@UIO-66/Pro were also used for the fabrication of biosensors for nitrofen with a wide linear range (0-100 µM), lower limit of detection, and good recovery rate.


Assuntos
Lipase/química , Compostos Organometálicos/química , Praguicidas/análise , Éteres Fenílicos/análise , Ácidos Ftálicos/química , Prolina/análogos & derivados , Saccharomycetales/enzimologia , Técnicas Biossensoriais/métodos , Estabilidade Enzimática , Enzimas Imobilizadas/química , Limite de Detecção , Modelos Moleculares
5.
ACS Appl Mater Interfaces ; 13(4): 5486-5497, 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33491443

RESUMO

Flexible paper-based sensors may be applied in numerous fields, but this requires addressing their limitations related to poor thermal and water resistance, which results in low service life. Herein, we report a paper-based composite sensor composed of carboxylic carbon nanotubes (CCNTs) and poly-m-phenyleneisophthalamide (PMIA), fabricated by a facile papermaking process. The CCNT/PMIA composite sensor exhibits an ability to detect pressures generated by various human movements, attributed to the sensor's conductive network and the characteristic "mud-brick" microstructure. The sensor exhibits the capability to monitor human motions, such as bending of finger joints and elbow joints, speaking, blinking, and smiling, as well as temperature variations in the range of 30-90 °C. Such a capability to sensitively detect pressure can be realized at different applied frequencies, gradient sagittas, and multiple twists with a short response time (104 ms) even after being soaked in water, acid, and alkali solutions. Moreover, the sensor demonstrates excellent mechanical properties and hence can be folded up to 6000 times without failure, can bear 5 kg of load without breaking, and can be cycled 2000 times without energy loss, providing a great possibility for a long sensing life. Additionally, the composite sensor shows exceptional Joule heating performance, which can reach 242 °C in less than 15 s even when powered by a low input voltage (25 V). From the perspective of industrialization, low-cost and large-scale roll-to-roll production of the paper-based sensor can be achieved, with a formed length of thousands of meters, showing great potential for future industrial applications as a wearable smart sensor for detecting pressure and temperature, with the capability of electric heating.


Assuntos
Nanotubos de Carbono/química , Papel , Fenilenodiaminas/química , Ácidos Ftálicos/química , Polímeros/química , Dispositivos Eletrônicos Vestíveis , Técnicas Biossensoriais/instrumentação , Condutividade Elétrica , Humanos , Monitorização Fisiológica/instrumentação , Movimento (Física) , Nanotubos de Carbono/ultraestrutura
6.
Carbohydr Polym ; 254: 117226, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33357841

RESUMO

Chemical modification of polysaccharides is an important approach for their transformation into customized matrices that suit different applications. Microwave irradiation (MW) has been used to catalyze chemical reactions. This study developed a method of MW-initiated synthesis for the production of phthalated cashew gum (Phat-CG). The structural characteristics and physicochemical properties of the modified biopolymers were investigated by FTIR, GPC, 1H NMR, relaxometry, elemental analysis, thermal analysis, XRD, degree of substitution, and solubility. Phat-CG was used as a matrix for drug delivery systems using benznidazole (BNZ) as a model drug. BNZ is used in the pharmacotherapy of Chagas disease. The nanoparticles were characterized by size, PDI, zeta potential, AFM, and in vitro release. The nanoparticles had a size of 288.8 nm, PDI of 0.27, and zeta potential of -31.8 mV. The results showed that Phat-CG has interesting and promising properties as a new alternative for improving the treatment of Chagas disease.


Assuntos
Anacardium/química , Sistemas de Liberação de Medicamentos , Gomas Vegetais/química , Doença de Chagas/tratamento farmacológico , Simulação por Computador , Humanos , Técnicas In Vitro , Espectroscopia de Ressonância Magnética , Microscopia de Força Atômica , Micro-Ondas , Estrutura Molecular , Nanopartículas/química , Nitroimidazóis/administração & dosagem , Tamanho da Partícula , Ácidos Ftálicos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Tripanossomicidas/administração & dosagem
7.
Food Chem ; 339: 127855, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32858384

RESUMO

A magnetic o-hydroxyazobenzene (M-HAzo) porous organic polymer was facilely prepared by a green azo coupling reaction in aqueous solution. The prepared M-HAzo was applied as a new adsorbent for the first time to pre-concentrate phthalate esters (PAEs) from plastic bottled juice, followed by their determination with high performance liquid chromatography-ultraviolet detection. The effects of various parameters, i.e., the mass ratio of the Fe3O4@SiO2 to HAzo, extraction time, ionic strength, pH of the sample, desorption conditions were optimized. Under the optimized conditions, the M-HAzo based method exhibited good performance in terms of linear range (0.3-50.0 µg L-1), detection limit (0.08-0.50 µg L-1), accuracy (recovery of 78.0-115.0%) and repeatability (relative standard deviation of 2.9-7.8%). This work provides a sensitive method for analysis of PAEs at trace levels in drinks, which is featured with high sensitivity, simple operation and environmentally-friendly merit and will have a promising potential in analysis of other organic pollutants.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ésteres/análise , Magnetismo , Ácidos Ftálicos/química , Compostos Azo/química , Ésteres/isolamento & purificação , Óxido Ferroso-Férrico/química , Sucos de Frutas e Vegetais/análise , Limite de Detecção , Polímeros/química , Reprodutibilidade dos Testes , Dióxido de Silício/química , Extração em Fase Sólida , Espectrofotometria Ultravioleta
8.
ACS Appl Mater Interfaces ; 13(1): 312-323, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33378177

RESUMO

In this study, we present a modulated synthesis nanocrystalline defective UiO-66 metal-organic framework as a potential chloroquine diphosphate (CQ) delivery system. Increasing the concentration of hydrochloric acid during the modulated synthesis resulted in a considerable increase of pore volume, which enhanced the CQ loading in CQ@UiO-66 composites. Drug release tests for CQ@UiO-66 composites have confirmed prolonged CQ release in comparison with pure CQ. In vivo tests on a Danio reiro model organism have revealed that CQ released from CQ@UiO-66 25% showed lower toxicity and fewer cardiotoxic effects manifested by cardiac malformations and arrhythmia in comparison to analogous doses of CQ. Cytotoxicity tests proved that the CQ loaded on the defective UiO-66 cargo resulted in increased viability of cardiac cells (H9C2) as compared to incubation with pure CQ. The experimental results presented here may be a step forward in the context of reducing the cardiotoxicity CQ.


Assuntos
Cloroquina/análogos & derivados , Cardiopatias/tratamento farmacológico , Estruturas Metalorgânicas/farmacologia , Nanopartículas/química , Animais , Cloroquina/efeitos adversos , Cloroquina/química , Cloroquina/farmacologia , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos/efeitos adversos , Liberação Controlada de Fármacos/efeitos dos fármacos , Células HEK293 , Cardiopatias/induzido quimicamente , Cardiopatias/patologia , Humanos , Ácido Clorídrico/farmacologia , Estruturas Metalorgânicas/química , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Ácidos Ftálicos/química , Ácidos Ftálicos/farmacologia , Peixe-Zebra/genética
9.
J Food Sci ; 85(9): 2832-2842, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32856302

RESUMO

Films were produced using the blown extrusion method from blends made with cassava and pinhão thermoplastic starch, compostable polyester (poly(butylene adipate co-terephthalate, PBAT) and natural extracts (rosemary and green tea). The effect of the incorporation of the extracts and the type of starch added in the film properties were investigated following the mixture design (23 ) approach. Regression models and response surface curves were generated to predict the film properties. The effect of the cold storage (6 °C and 17% of humidity relative, for 60 days) on the film properties was also investigated in order to simulate future applications. All the properties were mainly influenced by the extract type. The incorporation of the extracts decreased the lightness parameter and the films produced with green tea extract were more opaque than those made with rosemary. Starch/rosemary blends were more flexible, while the extract type did not have a significant effect on tensile strength (TS). Film elongation (ELO) ranged from 520% to 719% and might be comparable to some synthetic polymers. The water vapor permeability was improved in approximately 14% with addition of the extracts. The storage conditions, on the one hand, increased the TS, elastic modulus, and opacity of films and, on the other hand, decreased the elongation parameter. The thermal stability of films was not modified by adding extracts or varying the starch type. The results demonstrated that pinhão/cassava/PBAT blends and the natural extracts are a good alternative matrix to produce packagings with adequate mechanical and barrier properties. PRACTICAL APPLICATION: Extruded films produced from cassava or pinhão starch, poly(butylene adipate co-terephthalate) (PBAT) and natural extracts show technological potential to be used as active packaging for food products. Pinhão starch is a great alternative substitute to cassava starch and the incorporation of the commercial compostable polymer (PBAT) is necessary in order to confer suitable mechanical properties to extrusion process. The extrusion blown method, a process widely used by plastic industries, allows the scale-up of bio-based packagings for industrial scale.


Assuntos
Embalagem de Alimentos/instrumentação , Manihot/química , Extratos Vegetais/química , Amido/química , Módulo de Elasticidade , Umidade , Permeabilidade , Ácidos Ftálicos/química , Poliésteres/química , Polímeros/química , Vapor , Resistência à Tração
10.
J Chromatogr A ; 1626: 461347, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797827

RESUMO

Phthalate diesters are a group of plasticizers extensively used in the manufacturing and processing of plastics. Phthalate monoesters are the primary degradation products of the diesters. Accumulation of endocrine disruptive diesters and monoesters in soil is of great concern because of the extensive use of plastic mulching and misdisposal of plastics. Accurate determination of their levels in soil is critical to assess the occurrence, exposure, and risks of phthalate diesters and monoesters. In this study, we aimed to develop a robust and environmentally friendly method for the simultaneous determination of phthalate diesters and monoesters in soil. Ultra-performance liquid chromatography coupled with electrospray tandem mass spectrometry was used for quantification, combined with accelerated solvent extraction and in-line cleanup for sample preparation. The method detection limits for the 14 diesters and 11 monoesters were in the range of 0.59 to 10.08 ng g-1 d.w. Acceptable recoveries (69%-131%) for these analytes were obtained when four deuterated analogs were used for internal calibration, and intra- and inter-day variations were less than 15%. This method was later successfully applied to five soil samples, and 8 diesters and 7 monoesters were detected with the maximum concentration up to 1142.2 ng g-1 d.w. The method developed in this study can be used for screening and accurate quantification of phthalate diesters and monoesters in soil and possibly in other environmental matrices.


Assuntos
Ácidos Ftálicos/análise , Plastificantes/análise , Solo/química , Calibragem , Cromatografia Líquida de Alta Pressão/normas , Disruptores Endócrinos/análise , Disruptores Endócrinos/normas , Ésteres/química , Limite de Detecção , Ácidos Ftálicos/química , Ácidos Ftálicos/normas , Plastificantes/normas , Espectrometria de Massas em Tandem/normas , Temperatura
11.
Chemosphere ; 259: 127488, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32640376

RESUMO

A Ce-doped Ti/PbO2 electrode was prepared in a deposition solution containing Ce3+ and Pb2+ ions by electrodeposition, and the surface morphology, crystal structure and elemental states were characterized by SEM, XRD and XPS. The electrode was used to investigate the simultaneous degradation of three phthalate esters (PAEs), i.e., dimethyl phthalate (DMP), diethyl phthalate (DEP) and dibutyl phthalate (DBP) in synthetic wastewaters. The results showed that the electrode exhibited excellent electrocatalytic activity and good reusability and stability, and the removal efficiencies of 5 mg L-1 DBP, DMP and DEP in 0.05 M Na2SO4 (pH 7) reached 98.2%, 95.8% and 81.1% at current density of 25 mA cm-2 after 10 h degradation, respectively. The degradation processes followed pseudo first-order kinetic model very well, and the observed rate constants of DBP, DEP and DMP were 0.42, 0.40 and 0.29 h-1, respectively. The energy consumption in three PAEs degradation was also assessed. The main degradation products of the three PAEs were identified by using liquid chromatography-tandem mass spectrometry, and the possible degradation pathways mainly included dealkylation, hydroxyl addition, decarboxylation and benzene ring cleavage. This work is a promising candidate for efficient treatment of multiple PAEs in wastewater and protection of the aquatic ecological environment.


Assuntos
Cério/química , Galvanoplastia/métodos , Recuperação e Remediação Ambiental/métodos , Ácidos Ftálicos/química , Águas Residuárias/química , Poluentes Químicos da Água/química , Dibutilftalato/química , Eletrodos , Ésteres/química , Chumbo/química , Óxidos/química , Titânio/química
12.
Food Chem ; 333: 127537, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32683265

RESUMO

Antifungal bioplastic films were developed based on poly(lactic acid) (PLA) and poly(butylene adipate-co-terephthalate) (PBAT) blends as PLA60/PBAT40 (PLA/PBAT) and PBAT60/PLA40 (PBAT/PLA) with incorporated trans-cinnamaldehyde using cast-extrusion. Trans-cinnamaldehyde was more compatible in PLA which exhibited plasticization that increased molecular mobility, crystallinity, permeability but limited volatile release and reduced film strength. Interaction of trans-cinnamaldehyde modified CO functional groups of PLA and PBAT. Phase separation was higher in PBAT/PLA films due to less surface adhesion in PBAT networks. Higher release of trans-cinnamaldehyde enhanced bread crystallinity but gave lower rate of hardness increase due to plasticization of starch and protein and reduced lipid crystallinity. Increased bread hardness correlated with decreased water activity that was effectively prevented by higher release of trans-cinnamaldehyde. Films containing trans-cinnamaldehyde (2-10%) showed high antifungal efficacy against Penicillium sp. and Aspergillus niger but low effective against Rhizopus sp. Trans-cinnamaldehyde reduced bacterial and fungal growth in breads, extending shelf-life for 21 days.


Assuntos
Acroleína/análogos & derivados , Adipatos/química , Alcenos/química , Pão , Embalagem de Alimentos/métodos , Ácidos Ftálicos/química , Poliésteres/química , Acroleína/química , Antifúngicos/química , Pão/microbiologia , Permeabilidade , Amido/química
13.
Chemosphere ; 258: 127265, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32540534

RESUMO

Ferrate (Fe(VI)) is usually effective for oxidizing a variety of organic pollutants within a few seconds, but some recalcitrant asorganophosphorus pesticides such as dimethoate require higher dose of Fe(VI) and inorganic phosphorus produced by mineralization is difficult to remove. In this study, acid-activated ferrate (Fe(VI)) was firstly used to degrade organophosphorus pesticides dimethoate and simultaneously remove total phosphorus (TP) from solution under simulated sunlight. At a Fe(VI):dimethoate molar radio of 15:1, dimethoate was almost completely removed within 20 min and 47% of TP in the solution was removed by the reduction product of Fe(VI) within 240 min. Electron paramagnetic resonance (EPR) and terephthalic acid (TA) fluorescence experiments showed that •OH radicals were continuously generated in the system, and •OH formation pathway was proposed. Importantly, the involvement of •OH in acid-activated Fe(VI) process was confirmed for the first time by EPR. In the acid-activated Fe(VI)/simulated sunlight system, the removal of dimethoate and TP gradually increased with the decrement of activation pH, whereas the increase of molar ratio of Fe(VI):dimethoate enhanced the removal of dimethoate and TP. The addition of inorganic anions (HCO3- and NO2-) had obvious inhibitory effects on dimethoate and TP removal. Eight degradation products including O,O,S-trimethylphosphorothiate, omethoate and 2-S-methyl-(N-methyl) acetamide were determined by gas chromatography mass spectrometry (GC-MS) analysis, and two possible degradation pathways were proposed. The insights gained from this study open a new avenue to simultaneously degrade and remove organic contaminants.


Assuntos
Dimetoato/análise , Ferro/química , Praguicidas/análise , Ácidos Ftálicos/química , Luz Solar , Poluentes Químicos da Água/análise , Ferro/efeitos da radiação , Modelos Teóricos , Oxirredução , Purificação da Água/métodos
14.
Ecotoxicol Environ Saf ; 201: 110749, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32505048

RESUMO

BACKGROUND: Few epidemiological studies on the correlation between phthalate exposure and elderly obesity in China are available. The purpose of the present study is to assess phthalate exposure levels and explore the connections between exposure to phthalates and obesity using a sample of Chinese community-dwelling elderly individuals. METHODS: Data were acquired from the baseline survey of the Cohort of Health of Elderly and Controllable Factors of Environment, which was established in Lu'an, Anhui province, China, from June to September in 2016. Urine samples were obtained to analyze the concentrations of seven phthalate metabolites, utilizing a high-performance liquid chromatography-tandem mass spectrometry method. General obesity was determined based on body mass index, and abdominal obesity based on waist circumference. Binary logistic regression models were utilized to analyze the associations of creatinine-corrected phthalate metabolite concentrations (categorized into quartiles) with general and abdominal obesity in elderly people. Moreover, a stratified analysis was performed to explore the difference between genders. RESULTS: Of 942 elderly individuals, 52.9% were defined as generally obese and 75.5% as abdominally obese. The detection rates of seven phthalate metabolites ranged from 90.07% to 99.80%. The highest median concentration was 44.08 µg/l (for MBP), and the lowest was 0.55 µg/l (for MEHP). The level of exposure to LMW(low-molecular-weight) PAEs is higher than that to HMW(high-molecular-weight) PAEs. After adjustment for confounding variables, we found a significant association between urinary MEOHP (mono-2-ethyl-5-oxohexyl phthalate), MEHP (mono-2-ethylhexyl phthalate), MBP (mono-n-butyl phthalate), MEP (mono-ethyl phthalate), and MMP (mono-methyl phthalate) levels and general obesity. MBP levels were also correlated with abdominal obesity. When stratified by gender, higher urinary levels of MEOHP, MBP, MEP, and MMP were associated with general obesity in males, whereas MBP and MMP levels were eminently correlated with general obesity in females. Higher urinary MBP levels were associated with increased abdominal obesity rates in males, but not in females. CONCLUSIONS: In conclusion, higher phthalate metabolite concentrations were correlated with obesity in the elderly. Moreover, a gender difference was observed in these associations.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/urina , Obesidade/epidemiologia , Ácidos Ftálicos/urina , Idoso , Índice de Massa Corporal , China/epidemiologia , Estudos de Coortes , Exposição Ambiental/análise , Poluentes Ambientais/química , Feminino , Humanos , Masculino , Obesidade/urina , Ácidos Ftálicos/química , Fatores Sexuais
15.
J Food Sci ; 85(7): 2105-2113, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32506566

RESUMO

As a kind of polymer material additive, phthalic acid esters (PAEs) are widely used in food industry. However, PAEs are environmental endocrine disruptors with reproductive toxicity and teratogenic carcinogenicity, which are difficult to be degraded in the natural environment. In this paper, gas chromatography-mass spectrometer (GC-MS) methods for PAEs in polyethylene wrap film were optimized. For diisobutyl phthalate (DIBP) and dibutyl phthalate (DBP) that were mainly detected, the method had a good linearity in 1 to 500 ng/g. Then, we confirmed that the migration of DIBP and DBP from polyethylene wrap film increased with time and temperature. It is found that the migration law in different food simulations well followed the migration dynamics first-level model. The rate constant K1 and initial release rate V0 are inversely proportional to the polarity of the simulated liquid. We hope that this study can serve as a valuable reference for further research on the migration of food packing materials. PRACTICAL APPLICATION: In this paper, we present a simple example of applying migration model to evaluate the migration behaviors of PAEs in food packaging materials along with their hazardous properties. It can serve as a valuable reference for further research on the migration of food packing materials.


Assuntos
Embalagem de Alimentos/instrumentação , Ácidos Ftálicos/química , Polietileno/química , Dibutilftalato/análogos & derivados , Dibutilftalato/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Polímeros/química
16.
Chemosphere ; 253: 126653, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32302898

RESUMO

Novel brominated flame retardants (NBFRs) have been widely used and frequently detected in various environmental matrices. In this study, 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (TBB), bis-(2-ethylhexyl) tetrabromophthalate (TBPH) and their metabolites (namely 2,3,4,5-tetra-bromo benzoic acid (TBBA) and mono(2-ethylhexyl) tetrabromophthalate (TBMEHP)) were exposed to human umbilical vein endothelial cells (HUVECs). Metabolites can induce stronger cytotoxicity than parent compounds with EC50 at 47.3 (TBBA), 8.6 µg/ml (TBMEHP) vs > 200 µg/mL for parent compounds. Gene expression of platelet endothelial cell adhesion molecule-1, the gene associated with blood platelet kinetics, was significantly induced under TBBA and TBMEHP exposure. The in vivo test was consistent with gene expression result that the number of platelets in mouse blood was significantly increased after gavaged with 0.8 µg/mL TBBA and TBMEHP. In addition, TBB or TBPH were exposed to mice via gavage, and higher concentrations of TBBA (4 h, 60.8 ± 12.9 ng/mL, 8 h, 69.4 ± 2.24 ng/mL) in mouse blood were found than those of TBMEHP (4 h, 17.2 ± 4.01 ng/mL, 8 h, 12.8 ± 3.20 ng/mL), indicating that TBB was more readily in vivo metabolized than TBPH. The in vivo metabolism of TBB and TBPH and the stronger toxicity of their metabolites underscore the potential risk through NBFR exposure and the importance of understanding NBFR metabolism process.


Assuntos
Poluentes Ambientais/toxicidade , Retardadores de Chama/análise , Animais , Ácido Benzoico , Monitoramento Ambiental , Retardadores de Chama/metabolismo , Éteres Difenil Halogenados/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos , Cinética , Camundongos , Ácidos Ftálicos/química , Testes de Toxicidade , Veias Umbilicais
17.
Chemosphere ; 253: 126662, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32268253

RESUMO

In this study, pyrite (FeS2) was used as a novel activator of calcium peroxide (CaO2) for the degradation of diethyl phthalate (DEP) in both aqueous solution and soil. DEP (10 mg/L) in aqueous solution was completely degraded within 5.0 min by the FeS2 (0.30 g/L)/CaO2 (1.0 mM) system at pH 3.5. X-ray diffraction (XRD), scanning electron microscopy (SEM), electron paramagnetic resonance (EPR), free radical quenching, and X-ray photoelectron spectroscopy (XPS) were used to elucidate the mechanism of the catalytic decomposition of CaO2, radical formation and DEP degradation in the presence of by pyrite. The results show that hydroxyl radicals (OH) are the dominant active species responsible for DEP degradation. Surface or lattice Fe(II) of FeS2 readily activates H2O2 generated by CaO2 decomposition to produce OH, while the reducing sulfur species of FeS2 promotes the regeneration of surface of Fe(II) that catalyzes the production of additional OH, leading to the efficiently oxidative degradation of DEP. Although high concentration of common anions, such as Cl-, NO3-, SO42-, and HCO3-, exert inhibitory effects on DEP degradation by pyrite/CaO2, the reaction system can still efficiently degrade DEP in realistic soil. It was observed that 78% of DEP (25 mg kg-1) was degraded by 2.5% CaO2 (w/w) and 0.5% FeS2 (w/w) within 24 h. These results provide new insight into the mechanistic processes of CaO2 activation and OH formation by the novel FeS2 catalyst, demonstrating a promising alternative to the traditional H2O2-base Fenton process for contaminated soil remediation.


Assuntos
Ferro/química , Peróxidos/química , Ácidos Ftálicos/química , Sulfetos/química , Catálise , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres , Peróxido de Hidrogênio/química , Radical Hidroxila/química , Oxirredução , Espectroscopia Fotoeletrônica , Enxofre
18.
Food Chem ; 318: 126507, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32145544

RESUMO

Vegetables are easily contaminated by phthalate esters (PAEs) from the environment, agricultural films and fertilizers, affecting human health. In this paper, titanium dioxide (TiO2) nanotube arrays were prepared by electrochemical anodic oxidation on the surface of titanium wire. Covalent organic framework of TpBD was in situ bonded to the titanium wire via TiO2 nanotube arrays using monomers of 1,3,5-trimethylphloroglucinol (Tp) and benzidine (BD). The fabricated TpBD-TiO2 coated titanium wire was used as the solid-phase microextraction fiber to extract 11 PAEs in vegetable samples. Coupled with gas chromatography-tandem mass spectrometry (GC-MS/MS), the limits of detection for PAEs were from 0.001 (di-n-butyl phthalate) to 0.430 (butyl benzyl phthalate) µg/L (S/N = 3) and enrichment factors were between 226 (dimethyl phthalate) and 2154 (di-n-butyl phthalate). Our fabricated TpBD-TiO2 fiber can be used at least 150 times without significant loss of extraction efficiency (<4.8%). Quantitative determination of PAEs in vegetable samples (tomato, lettuce, cucumber) was achieved by standard addition.


Assuntos
Ésteres/isolamento & purificação , Contaminação de Alimentos/análise , Ácidos Ftálicos/isolamento & purificação , Microextração em Fase Sólida/métodos , Titânio/análise , Verduras/química , Ésteres/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Limite de Detecção , Estruturas Metalorgânicas/química , Ácidos Ftálicos/química , Microextração em Fase Sólida/instrumentação , Espectrometria de Massas em Tandem/métodos , Titânio/química
19.
ACS Appl Mater Interfaces ; 12(10): 11409-11418, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32067445

RESUMO

In this work, we fabricated a dual-wavelength electrochemiluminescence ratiometric biosensor based on electrochemiluminescent resonance energy transfer (ECL-RET). In this biosensor, Au nanoparticle-loaded graphitic phase carbon nitride (Au-g-C3N4) as a donor and Au-modified dimethylthiodiaminoterephthalate (TAT) analogue (Au@TAT) as an acceptor were investigated for the first time. Besides, tetrahedron DNA probe was immobilized onto Au-g-C3N4 to improve the binding efficiency of the transcription factor and ECL ratiometric changes on the basis of the ratio of ECL intensities at 595 and 460 nm, which were obtained through the formation of a sandwich structure of DNA probe-antigen-antibody. Our biosensor achieved the assay of NF-κB p50 with a detection limit of 5.8 pM as well as high stability and specificity.


Assuntos
Técnicas Biossensoriais/métodos , DNA/química , Técnicas Eletroquímicas/métodos , Subunidade p50 de NF-kappa B/análise , Nanoestruturas/química , Corantes Fluorescentes/química , Humanos , Sondas Moleculares/química , Ácidos Ftálicos/química
20.
Chemosphere ; 249: 126153, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32058129

RESUMO

In this study, we determined DNA damage and chromosome breakage (indicators of genotoxicity) and cell viability (an indicator of cytotoxicity) in human lymphoblastoid TK6 and Chinese hamster ovary (CHO) cells treated with 33 e-liquids using in vitro single cell gel (comet), micronucleus (MN), and trypan blue assays, respectively. We also measured the contents of nicotine, five phthalate esters, and DL-menthol in the e-liquids to examine their effects on DNA damage, chromosome breakage, and cell viability. Our chemical analyses showed that: (1) six e-liquids had nicotine ≥2-fold higher than the manufacture's label claim (2-3.5 mg); (2) both dimethyl- and dibutyl-phthalate levels were >0.1 µg/g, i.e., their threshold limits as additives in cosmetics; and (3) the DL-menthol contents ranged from 0.0003 to 85757.2 µg/g, with those of two e-liquids being >1 mg/g, the threshold limit for trigging sensory irritation. Though all the e-liquids induced DNA damage in TK6 cells, 20 resulted in cell viabilities ≤75%, indicating cytotoxicity, yet the inverse relationship between cell viability and DNA damage (r = -0.628, p = 0.003) might reflect their role as pro-apoptotic and DNA damage inducers. Fifteen e-liquids induced MN% in TK6 cells ≥3-fold that of untreated cells. Some of the increase in %MN might be false due to high cytotoxicity, yet six brands showed acceptable cell viabilities (59-71%), indicating chromosome damage. DNA damage and %MN increased when the TK6 cells were exposed to metabolic activation. The CHO cells were less sensitive to the genotoxic effects of the e-liquids than the TK6 cells. DL-menthol was found to be associated with decreased cell viability and increased DNA damage, even at low levels. We cannot dismiss the presence of other ingredients in e-liquids with cytotoxic/genotoxic properties since out of the 63 different flavors, 47 induced DNA damage (≥3-folds), and 26 reduced cell viability (≤75%) in TK6 cells.


Assuntos
Vapor do Cigarro Eletrônico/química , Ácidos Ftálicos/química , Animais , Células CHO , Sobrevivência Celular/efeitos dos fármacos , Cricetinae , Cricetulus , Dano ao DNA , Dibutilftalato/farmacologia , Vapor do Cigarro Eletrônico/análise , Vapor do Cigarro Eletrônico/toxicidade , Ésteres/química , Humanos , Mentol/química , Mentol/toxicidade , Testes para Micronúcleos/métodos , Nicotina/química , Nicotina/toxicidade
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