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1.
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
2.
Environ Sci Pollut Res Int ; 27(8): 7785-7794, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31889277

RESUMO

Due to their pervasive applications, phthalic acid esters or phthalates have ample presence in all environmental compartments. A principal source of their existence in freshwater is phthalate-laden wastewater treatment plant effluents. For its sustainable operation and biogas production, wastewater treatment scheme of up flow anaerobic sludge blanket (UASB) and polishing pond is more prevalent in developing countries. This yearlong study focused on evaluating the occurrence, fate and risk of four priority phthalates, diethyl phthalate (DEP), dibutyl phthalate (DBP), benzylbutyl phthalate (BBP), and diethylhexyl phthalate (DEHP) in a UASB+ polishing pond-based wastewater treatment plant. Concentration of the phthalates in raw wastewater ranged from nd to 17.36 µg/L (DEP), 0.92 to 18.26 µg/L (DBP), nd to 6.54 µg/L (BBP), and nd to 53.21 µg/L (DEHP). DEHP concentrations in UASB sludge were below 100 mg/kg, the recommended limit by the European Union for safe disposal of dewatered sludge. All four compounds were removed approximately 80% in the wastewater treatment plant, with larger removal in polishing pond than UASB. Sorption contributes a significant portion of BBP and DEHP removal (15-24%) in UASB than DEP and DBP (0-3%). Seasonally, larger removals of phthalates were observed during the summer season. Risk assessment showed that the treated effluents had low risk of DEP, DBP, and BBP. However, the hazard quotient (HQ) of DEHP was greater than 1. To comply with regulations, dilution requirement of effluents was investigated which showed that a dilution factor of 4.4 in summer and 2.1 in winter is required for effluents of UASB + Pond-based treatment plant.


Assuntos
Disruptores Endócrinos , Ácidos Ftálicos/análise , Águas Residuárias/análise , Disruptores Endócrinos/análise , Monitoramento Ambiental , Ácidos Ftálicos/química , Eliminação de Resíduos Líquidos
3.
J Environ Sci Health B ; 55(1): 60-68, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31971076

RESUMO

This work reports the development of a very-simple-to-construct stir-bar extraction device so called "a dumbbell-shaped stainless steel stir-bar." The extraction device was assembled from a rolled up stainless steel net filled with an XAD-2 sorbent and a metal rod to allow the use of a magnetic stirrer during extraction. The dumbbell-shaped stainless steel stir-bar was used to extract diethyl phthalate (DEP), dibutyl phthalate (DBP), and di(2-ethylhexyl) phthalate (DEHP) before analysis by a gas chromatograph equipped with an electron capture detector (GD-ECD). Under the optimal conditions, the developed method provided a good linearity from 10.0 to 1,000.0 ng mL-1 for all three compounds. Limits of detection and limits of quantification were 9.37 ± 0.29 ng mL-1 and 31.22 ± 0.95 ng mL-1 for DEP, 5.73 ± 0.31 ng mL-1 and 19.1 ± 1.0 ng mL-1 for DBP and 3.30 ± 0.06 ng mL-1 and 11.0 ± 0.19 ng mL-1 for DEHP, respectively. Good recoveries in the range of 81.89 ± 0.17 to 109.5 ± 2.0% were achieved when the method was used to extract phthalate esters in five instant noodle and two rice soup samples.


Assuntos
Fracionamento Químico/instrumentação , Análise de Alimentos/instrumentação , Oryza , Ácidos Ftálicos/isolamento & purificação , Aço Inoxidável , Fracionamento Químico/métodos , Cromatografia Gasosa , Dibutilftalato/isolamento & purificação , Dietilexilftalato/isolamento & purificação , Desenho de Equipamento , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Limite de Detecção , Ácidos Ftálicos/química , Reprodutibilidade dos Testes
4.
Food Chem ; 314: 126179, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31968292

RESUMO

In this study, for the first time, hollow fiber and monolithic fiber were fabricated based on metal-organic framework deep eutectic solvents/molecularly imprinted polymers (MOF- DES/MIPs) and were used for microextraction of phthalate esters under termed hollow fiber liquid membrane-protected solid-phase microextraction (HFLMP-SPME) followed by gas chromatography- flame ionization detection. Several parameters influencing extraction recoveries of phthalate esters including adsorption and desorption parameters were investigated and optimized using fabricated MOF- DES/MIPs monolithic fiber. Under optimal conditions, detection limits (S/N = 3) of the method were in a range of 0.008-0.03 µg L-1 and limits of quantification (S/N = 10) were between 0.028 and 0.12 µg L-1. RSD (%) for intra-day and inter-day precisions were between 2.4-4.7% and 2.6-3.4%, respectively. Subsequently, this procedure was successfully applied with satisfactory results in the determination of phthalate esters in yogurt, water, and soybean oil samples. The R (%) ranged from 95.5 to 100.0% in different samples.


Assuntos
Estruturas Metalorgânicas/química , Impressão Molecular/métodos , Microextração em Fase Sólida/métodos , Óleo de Soja/química , Água/química , Iogurte/análise , Adsorção , Cromatografia Gasosa , Ésteres/química , Limite de Detecção , Impressão Molecular/instrumentação , Ácidos Ftálicos/química , Polímeros/química , Microextração em Fase Sólida/instrumentação , Solventes/química
5.
Chem Commun (Camb) ; 56(1): 125-128, 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31793952

RESUMO

We compare the ability of a prototypical dicarboxylic acid and its fluorinated analogue to act as molecular building blocks for the formation of self-assembled monolayers. Whilst fluorination is found to prevent homomolecular self-assembly, it greatly increases the ability of the carboxylic acid to act as a hydrogen bond donor for the formation of bimolecular networks.


Assuntos
Fluorbenzenos/química , Ácidos Ftálicos/química , Piridinas/química , Triazinas/química , Halogenação , Ligação de Hidrogênio
6.
Food Chem ; 311: 125918, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31869647

RESUMO

Multilayer materials used in food packaging are commonly manufactured with a polyurethane adhesive layer in its structure that may contain cyclic esters oligomers as potential migrants. However, little is known about their toxicity. In this work, two cyclic esters of polyurethane are evaluated in migration from 20 multilayer packaging samples. They were composed by adipic acid (AA), diethylene glycol (DEG) and isophthalic acid (IPA) and their structure was AA-DEG and AA-DEG-IPA-DEG. The concentration of these compounds in migration exceeded the maximum level established by Regulation EU/10/2011 (10 ng g-1). Bioaccessibility of both compounds was evaluated by studying gastric and intestinal digestion. The studies showed that the concentration of the compounds decreased during digestion and that their hydrolysed molecules increased. Furthermore, endocrine activity in vitro assays were performed. A weak androgen receptor antagonism was identified, whereas no arylhydrocarbon receptor activity or binding to the thyroid hormone transport protein was found.


Assuntos
Adesivos/química , Embalagem de Alimentos/instrumentação , Poliésteres/química , Poliuretanos/química , Adipatos/química , Adipatos/toxicidade , Antagonistas de Receptores de Andrógenos/química , Antagonistas de Receptores de Andrógenos/toxicidade , Linhagem Celular , Etilenoglicóis/química , Etilenoglicóis/toxicidade , Contaminação de Alimentos/análise , Humanos , Ácidos Ftálicos/química , Ácidos Ftálicos/toxicidade , Poliuretanos/toxicidade
7.
Ecotoxicol Environ Saf ; 190: 109143, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31865203

RESUMO

Phthalate esters (PAEs) are one of the most frequently detected organic pollutants in soils. In this work, the adsorption behaviors of di-ethyl phthalate (DEP) and dibutyl phthalate (DBP) on soils, humins (HM) and Clay organo-mineral complexes (Clay-OM) from four regions in China, Changchun (CC), Cangzhou (CZ), Yinchuan (YC), and Changsha (CS) were studied. The surface and structural properties of these sorbents were characterized using Brunauer-Emmett-Teller specific surface area, Fourier transform infrared spectroscopy, X-ray diffraction spectroscopy, and 13C nuclear magnetic resonance methods. The results showed that the CC soil has the largest pore volume (PV) and specific surface area (SSA). PV, SSA, and aliphatic carbon content of the samples ranked as Clay-OM > HM > soil. Adsorption experiments indicated that the Clay-OM exhibited the strongest adsorption affinity for both DBP and DEP, followed by HM, and then the soil samples. Furthermore, DEP and DBP adsorption amounts on the samples declined as follows: CC > CS > CZ > YC. To illustrate the dominant mechanisms for PAEs adsorption onto soil, the soil organic carbon content normalized adsorption coefficient (LogKoc) was correlated with several possible parameters using multiple parameter linear regression and significance testing. The R2 values of the DBP and DEP in multi-regression equations were 0.825 and 0.741 respectively, and the significance test suggested that pore structure and specific surface area had crucial influences on the adsorption progress.


Assuntos
Dibutilftalato/química , Ácidos Ftálicos/química , Poluentes do Solo/química , Adsorção , Carbono/análise , China , Argila/química , Ésteres , Substâncias Húmicas , Minerais/química , Solo/química
8.
Mater Sci Eng C Mater Biol Appl ; 107: 110291, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31761240

RESUMO

Electrospinning is a valuable technology for cartilage tissue engineering (CTE) due to its ability to produce fibrous scaffolds mimicking the nanoscale and alignment of collagen fibers present within the superficial zone of articular cartilage. Coaxial electrospinning allows the fabrication of core-shell fibers able to incorporate and release bioactive molecules (e.g., drugs or growth factors) in a controlled manner. Herein, we used coaxial electrospinning to produce coaxial poly(glycerol sebacate) (PGS)/poly(caprolactone) (PCL) aligned nanofibers (core:PGS/shell:PCL). The obtained scaffolds were characterized in terms of their structure, chemical composition, thermal properties, mechanical performance and in vitro degradation kinetics, in comparison to monoaxial PCL aligned fibers and respective non-aligned controls. All the electrospun scaffolds produced presented average fiber diameters within the nanometer-scale and the core-shell structure of the composite fibers was clearly confirmed by TEM. Additionally, fiber alignment significantly increased (>2-fold) the elastic modulus of both coaxial and monoxial scaffolds. Kartogenin (KGN), a small molecule known to promote mesenchymal stem/stromal cells (MSC) chondrogenesis, was loaded into the core PGS solution to generate coaxial PGS-KGN/PCL nanofibers. The KGN release kinetics and scaffold biological performance were evaluated in comparison to KGN-loaded monoaxial fibers and respective non-loaded controls. Coaxial PGS-KGN/PCL nanofibers showed a more controlled and sustained KGN release over 21 days than monoaxial PCL-KGN nanofibers. When cultured with human bone marrow MSC in incomplete chondrogenic medium (without TGF-ß3), KGN-loaded scaffolds enhanced significantly cell proliferation and chondrogenic differentiation, as suggested by the increased sGAG amounts and chondrogenic markers gene expression levels. Overall, these findings highlight the potential of using coaxial PGS-KGN/PCL aligned nanofibers as a bioactive scaffold for CTE applications.


Assuntos
Anilidas , Cartilagem , Nanofibras/química , Ácidos Ftálicos , Engenharia Tecidual , Tecidos Suporte , Anilidas/química , Anilidas/metabolismo , Anilidas/farmacocinética , Anilidas/farmacologia , Cartilagem/citologia , Cartilagem/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Decanoatos/química , Técnicas Eletroquímicas , Desenho de Equipamento , Glicerol/análogos & derivados , Glicerol/química , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Ácidos Ftálicos/química , Ácidos Ftálicos/metabolismo , Ácidos Ftálicos/farmacocinética , Ácidos Ftálicos/farmacologia , Poliésteres/química , Polímeros/química , Engenharia Tecidual/instrumentação , Engenharia Tecidual/métodos
9.
Chemosphere ; 240: 124875, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31541899

RESUMO

Adsorptive removal of phthalate esters from wastewater combined with their persulfate (PS) catalytic degradation has attracted the attention of many researchers. In this study, the adsorptive and catalytic properties of an MIL100 material obtained by a green synthetic route have been optimized by a surface molecular imprinting technique. Results have shown that there are two steps in the molecular imprinting process. A polymerization is first carried out in the internal channels of the material and the imprinting layer is then formed on the surface. The relative proportions of the starting materials for the synthesis have been optimized through the design of a three-dimensional response surface. The amount of pollutant adsorbed was increased fourfold after surface imprinting, reaching 13.6 mg g-1. The homogeneity of the recognition sites has been evaluated by dynamics calculations and the Freundlich equation. The selective adsorption ability of the material for diethyl phthalate was improved, and the process involved chemical adsorption. The catalytic properties of the material after imprinting were increased about 1.5-fold, indicating that selective adsorption is important. Such molecularly imprinted polymers may potentially serve as good functional materials for the removal of phthalate esters from wastewater.


Assuntos
Impressão Molecular/métodos , Ácidos Ftálicos/química , Águas Residuárias/química , Polímeros/química
10.
Ultrason Sonochem ; 60: 104749, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31494466

RESUMO

The effectiveness and synergistic mechanisms of combining ultrasonic process (US) with peroxymonosulfate (PMS) were investigated using Bisphenol A (BPA) and Dimethyl Phthalate (DMP) as the model pollutants. Synergy between US and PMS improved the degradation of target pollutants, and PMS was found to play a dual role. The optimum dosage of PMS and the extent of efficiency promotion were found to depend on not only the ultrasonic frequency but also on the hydrophobicity of target pollutants. The scavenger quenching experiments and electron paramagnetic resonance analysis indicated that OH was responsible for DMP degradation in both US and US/PMS processes. The chemical probe experiments also proved that activation of PMS could increase the production of OH while excess PMS consumed the available radicals. Furthermore, it was found for the first time that the constituent salts of KHSO4 and K2SO4 in the commercial Oxone also made considerable influence on US/PMS process. It was also found that the combination of US and PMS showed more pronounced synergistic effect for treating DMP at lower concentrations. Higher efficiency was achieved at more acidic condition and similar efficiencies were obtained at pH range of 5.1 ~ 8.12. DMP degradation pathways were found to be the OH addition to the aromatic ring and hydrogen absorption at the aliphatic chains with and without the presence of PMS, but much better mineralization capability was obtained in the presence of PMS than ultrasonic degradation alone.


Assuntos
Disruptores Endócrinos/química , Peróxidos/química , Ondas Ultrassônicas , Compostos Benzidrílicos/química , Espectroscopia de Ressonância de Spin Eletrônica , Sondas Moleculares , Oxirredução , Fenóis/química , Ácidos Ftálicos/química , Poluentes Químicos da Água/química
11.
Sheng Wu Gong Cheng Xue Bao ; 35(11): 2104-2120, 2019 Nov 25.
Artigo em Chinês | MEDLINE | ID: mdl-31814358

RESUMO

Phthalates esters (PAEs) are important organic compounds used as plasticizers to enhance their plasticity and versatility. At the same time, PAEs are also typical environmental endocrine disruptors. Long-term production and use of plastic products have caused harm to the environment and organisms, as well as human health. Previous studies found that biodegradation has become a main pathway to reduce PAEs in the environment. This article reviews PAEs' structural characteristics and classifications, toxicology, pollution in the environment, summarizes the diversity of PAEs-degrading bacterial species, and explores the possible mechanisms of bacterial PAEs degradation. The article may provide some reference in solving the problem of PAEs pollution.


Assuntos
Biodegradação Ambiental , Ésteres , China , Poluição Ambiental , Ésteres/química , Ésteres/metabolismo , Ácidos Ftálicos/química , Ácidos Ftálicos/metabolismo , Plastificantes/química , Plastificantes/metabolismo
12.
Chem Commun (Camb) ; 55(89): 13458-13461, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31647069

RESUMO

Here, an enzyme mimic inspired by serine proteases was developed for the degradation of PAEs. This enzyme mimic, comprised an active site (SHD), a self-assembling polypeptide (LKLKLKL), a spacer (GGG) and a polymerizable site (DOPA) and showed high activity towards the degradation of DEHP in cells.


Assuntos
Dietilexilftalato/metabolismo , Ésteres/metabolismo , Ácidos Ftálicos/metabolismo , Serina Proteases/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Dietilexilftalato/química , Dietilexilftalato/farmacologia , Ésteres/química , Ésteres/farmacologia , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Ácidos Ftálicos/química , Ácidos Ftálicos/farmacologia , Serina Proteases/química , Propriedades de Superfície , Temperatura
13.
ACS Appl Mater Interfaces ; 11(38): 34744-34754, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31475824

RESUMO

Here, kartogenin (KGN), an emerging stable nonprotein compound with the ability to promote differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) into chondrocytes, was grafted onto the surface of modified ultrasmall superparamagnetic iron-oxide (USPIO) and then integrated into cellulose nanocrystal/dextran hydrogels. The hydrogels served as a carrier for the USPIO-KGN and a matrix for cartilage repair. We carried out in vitro and in vivo studies, the results of which demonstrated that KGN undergoes long-term stable sustained release, recruits endogenous host cells, and induces BMSCs to differentiate into chondrocytes, thus enabling in situ cartilage regeneration. Meanwhile, the USPIO-incorporated theranostic hydrogels exhibited a distinct magnetic resonance contrast enhancement and maintained a stable relaxation rate, with almost no loss, both in vivo and in vitro. According to noninvasive in vivo observation results and immunohistochemistry analyses, the regenerated cartilage tissue was very similar to natural hyaline cartilage. This innovative diagnosis and treatment system increases the convenience and effectiveness of chondrogenesis.


Assuntos
Anilidas , Cartilagem , Hidrogéis , Nanopartículas de Magnetita , Ácidos Ftálicos , Regeneração/efeitos dos fármacos , Anilidas/química , Anilidas/farmacologia , Animais , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Cartilagem/lesões , Cartilagem/patologia , Cartilagem/fisiologia , Diferenciação Celular/efeitos dos fármacos , Condrócitos/metabolismo , Condrócitos/patologia , Hidrogéis/química , Hidrogéis/farmacologia , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/uso terapêutico , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/patologia , Ácidos Ftálicos/química , Ácidos Ftálicos/farmacologia , Coelhos , Nanomedicina Teranóstica
14.
Environ Sci Pollut Res Int ; 26(31): 31644-31653, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31485943

RESUMO

In this study, poly(ethylene terephthalate) fibers grafted with 4-vinyl pyridine (PET-g-4VP) was synthesized with using a radical polymerization method and its removal capacity for bromate ions in the aqueous solution was explored. The synthesized graft copolymer was structurally characterized by scanning electron microscopy (SEM) and Fourier transformed infrared spectroscopy (FTIR). The effect of some parameters such as pH, grafting rate, processing time, and ion concentration on bromate removal was examined with batch experiments. The sorptions of bromate onto the PET-g-4VP fibers were both verified with FTIR and X-ray fluorescence analysis (XRF) and the remaining amount of bromate after adsorption process was determined with an ion chromatography (Shimadzu). Moreover, kinetic and isotherm studies were also performed for adsorption of bromate with the grafted fibers. The point of zero charge (pHpzc) of the PET-g-4VP fibers was found to be 7.5 and the fibers removed maximum amount of bromate from aqueous solution at pH 3. Equilibrium time of adsorption was determined to be 75 min and the adsorption kinetic was found to be pseudo-second-order model. It was observed that the increase in the amount of grafted 4VP onto the PET fibers increased the bromate removal capacity of the fibers; however, when the grafting yield of 4VP was over 80%, the bromate removal ability of the fibers decreased. The maximum bromate removal capacity of the PET-g-4VP was determined to be 183 mg/g when the initial bromate amount was 800 mg/L, treatment time was 75 min, pH of the solution was 3, and 4VP grafting yield was 80%. When the initial bromate concentration was higher than 800 mg/L, the removal rate of the PET-g-4VP fibers was not changed. In addition, bromate ion adsorption data indicated compliance with the Freundlich isotherm. The adsorbent fibers obtained by this study may be promising candidates for the removal of bromate ions from the aqueous media.


Assuntos
Bromatos/química , Íons/química , Ácidos Ftálicos/química , Polietilenotereftalatos/química , Piridinas/química , Poluentes Químicos da Água/análise , Adsorção , Cinética , Piridinas/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Água , Poluentes Químicos da Água/química
15.
Environ Sci Pollut Res Int ; 26(27): 28256-28269, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31368075

RESUMO

Environmental exposure to phthalates may contribute to an increased risk of asthma in children and adults. We aimed to assess the direction and strength of the association between urinary phthalates metabolites and current asthma in children and adults that participated in the National Health and Nutrition Examination Survey (NHANES) 2007-2012. Data on ten urinary phthalate metabolites, self-reported questionnaires, spirometry measures, and covariates were obtained from 7765 participants (28.1% were children aged 6-17 years) taking part in the NHANES 2007-2012. Asthma was assessed using self-reported questionnaires for children and adults, and via spirometry measures for adults alone. We used crude and adjusted logistic regression models to estimate the odds ratios (ORs) and 95% confidence interval (CI) per one log10 unit change in the concentration of phthalate metabolites. We further modeled the effect modification by sex. Out of 10 metabolites, only mono-benzyl phthalate (MBzP) was positively associated with the prevalence of self-reported asthma in children, after adjusting for a range of potential confounders (odds ratio 1.54; 95% confidence interval 1.05-2.27). No significant relationship was observed for adults. The association of mono-ethyl phthalate (MEP) was modified by sex, with significantly increased odds of asthma among males [boys (2.00; 1.14-3.51); adult males (1.32; 1.04-1.69)]. While no other phthalates showed a positive relationship with current asthma in males, mono-(carboxynonyl) phthalate (MCNP) and mono-(3-carboxylpropyl) phthalate (MCPP) were inversely associated with spirometrically defined asthma in adult females. A sex-specific relationship in adults was evident when spirometry, but not self-reported measures were used to define asthma. We found no clear association between exposure to phthalates and current asthma, except for a significant relationship between MBzP metabolites and self-reported asthma in children. As a result, exposure to phthalates and asthma development and/or exacerbations remains controversial, suggesting a need for a well-designed longitudinal study.


Assuntos
Asma/induzido quimicamente , Exposição Ambiental/efeitos adversos , Ácidos Ftálicos/efeitos adversos , Ácidos Ftálicos/química , Adolescente , Adulto , Criança , Feminino , Humanos , Modelos Logísticos , Estudos Longitudinais , Masculino , Inquéritos Nutricionais , Razão de Chances , Ácidos Ftálicos/metabolismo , Autorrelato , Inquéritos e Questionários , Adulto Jovem
16.
Dalton Trans ; 48(34): 13017-13025, 2019 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-31403139

RESUMO

Lysosome visualization is very important for accurate diagnosis of human diseases. However, currently developed lysosome imaging probes usually have poor specificity and are easily quenched, leading to a low signal to noise ratio in lysosome labeling. To resolve this problem, herein, metal-organic framework-based probes of copper-terephthalic acid (CuBDC) are investigated, which show sensitivity to pH and hydrogen peroxide (H2O2), simultaneously. By self-assembling under the template effect of soluble starch, the particle size of CuBDC can be well controlled for entering into cells and locating lysosomes. Based on the Fenton-like reaction, CuBDC can catalyze the decomposition of H2O2 into ˙OH, which in turn reacts with CuBDC to generate a stable fluorescent substance. Meanwhile, Cu2+ can be released from CuBDC under acidic conditions for reacting with H2O2 more thoroughly. And the synthesized CuBDC has a similar attraction to the electrophilic ˙OH at different pH values owing to the residual soluble starch in the particles. The above properties cause CuBDC to have a stable fluorescence signal with low pH values and high H2O2 concentration, simultaneously. The fluorescence imaging experiments in HeLa cells demonstrate that CuBDC acting as a pH/H2O2 responsive fluorescent probe holds great promise for lysosome-specific imaging.


Assuntos
Cobre/química , Corantes Fluorescentes/química , Peróxido de Hidrogênio/metabolismo , Lisossomos/metabolismo , Imagem Óptica/métodos , Ácidos Ftálicos/química , Amido/química , Corantes Fluorescentes/metabolismo , Células HeLa , Humanos , Concentração de Íons de Hidrogênio
17.
Sci Total Environ ; 694: 133705, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31386955

RESUMO

We prepared carbon nanofiber (CCNF) using cellulose as the carbon source in this study and utilized for the first time as the support to enhance the catalytic performance of the cobalt ferrite (CoFe2O4) for peroxymonosulfate (PMS) activation. The catalytic capability of the CoFe2O4/CCNF nanocomposites activated PMS was investigated through degrading dimethyl phthalate (DMP), a classical organic pesticide pollutant, in water media. The influence factors like CCNF content, nanocomposite and PMS dosage, DMP content, and pH value on the degradation speed were systematically investigated and analyzed. Since CoFe2O4 is a spinel structured molecule which is magnetically separable, the reusability of the prepared CoFe2O4/CCNF nanocomposites under multiple cycles was also tested. Besides, the degradation intermediates during the catalytic process were also analyzed and identified by liquid chromatography-mass spectrometry (LC-MS) with a possible degradation mechanism. The results indicated that the prepared nanocomposite had promising catalytic capability in degrading DMP, in which the SO4- radicals played the main role as the active oxidation agent. Furthermore, the CoFe2O4/CCNF nanocomposites exhibited very good stability and reusability. The present study provides a clean biochar supported catalyst which could readily enhance the PMS activation efficiency for recycled decontamination of refractory organic pollutants in water media.


Assuntos
Modelos Químicos , Nanofibras/química , Peróxidos/química , Ácidos Ftálicos/química , Carbono , Celulose/química , Carvão Vegetal
18.
Chemosphere ; 237: 124450, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31394450

RESUMO

The work detailed here investigated the efficiency of oxidising technologies in clearing aqueous solutions of di-n-butyl phthalate (DBP), a known endocrine-disrupting compound (EDCs). Specifically, this paper addresses the use of the classic Fenton process, and the development of a modification of Fenton's reagent targeted at the degradation of di-n-butyl phthalate in aqueous solution. The modification in question entailed the use of alternative catalysts or a mixture thereof. Hence oxidation by hydrogen peroxide (at various different concentrations), the classic Fenton process, was tested for the removal of DBP, alongside versions modified in terms of the quantitative and qualitative composition of a mixture of catalysts, and the presence of metal ions, as well as the factors of time, pH and initial DBP concentration. Given that it did not exceed 31%, the degradation of DBP we achieved using H2O2 could not be regarded as satisfactory. In contrast, the addition of 2.5 mM L-1 of Fe2+ was found to mediate almost complete elimination of the phthalate from the model solution. Also confirmed by experimentation were the benefits of using homogeneous catalysts (compounds of copper(II) and manganese(II)) as alternatives to Fe2+ in the Fenton reagent. A key experimental achievement was to confirm the applicability of a catalyst formed from a mixture of 2 or 3 types of transition metal ion. A Fenton reaction extended to ions like Mn2+ and Cu2+ in particular is seen to eliminate factors/parameters discouraging practical industrial use of the classic Fenton process.


Assuntos
Dibutilftalato/química , Recuperação e Remediação Ambiental , Poluentes Químicos da Água/química , Catálise , Cobre/química , Disruptores Endócrinos/química , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Ferro/química , Metais/química , Oxirredução , Ácidos Ftálicos/química , Soluções , Poluentes Químicos da Água/análise
19.
J Agric Food Chem ; 67(31): 8548-8558, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31266305

RESUMO

Herein, we report a double enzyme system to degrade 12 phthalate esters (PAEs), particularly bulky PAEs, such as the widely used bis(2-ethylhexyl) phthalate (DEHP), in a one-pot cascade process. A PAE-degrading bacterium, Gordonia sp. strain 5F, was isolated from soil polluted with plastic waste. From this strain, a novel esterase (GoEst15) and a mono(2-ethylhexyl) phthalate hydrolase (GoEstM1) were identified by homology-based cloning. GoEst15 showed broad substrate specificity, hydrolyzing DEHP and 10 other PAEs to monoalkyl phthalates, which were further degraded by GoEstM1 to phthalic acid. GoEst15 and GoEstM1 were heterologously coexpressed in Escherichia coli BL21 (DE3), which could then completely degrade 12 PAEs (5 mM), within 1 and 24 h for small and bulky substrates, respectively. To our knowledge, GoEst15 is the first DEHP hydrolase with a known protein sequence, which will enable protein engineering to enhance its catalytic performance in the future.


Assuntos
Proteínas de Bactérias/química , Esterases/química , Ésteres/química , Gordonia (Bactéria)/enzimologia , Ácidos Ftálicos/química , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biocatálise , Biodegradação Ambiental , Dietilexilftalato/química , Dietilexilftalato/metabolismo , Esterases/genética , Esterases/metabolismo , Ésteres/metabolismo , Gordonia (Bactéria)/genética , Gordonia (Bactéria)/isolamento & purificação , Gordonia (Bactéria)/metabolismo , Hidrólise , Ácidos Ftálicos/metabolismo , Alinhamento de Sequência , Microbiologia do Solo
20.
Environ Sci Pollut Res Int ; 26(25): 25690-25701, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31267401

RESUMO

In this study, wastewater from municipal services, such as a port wastewater reception facility (PRF-WW) and a municipal solid waste plant (MSWP), was tested for the presence of the suspected endocrine-disrupting compounds phthalates (PAEs) and bisphenol A (BPA). PAEs and BPA were found in this study in high concentrations in raw wastewater obtained from passenger ships (RMT-WWs) (up to 738 µg/L and 957 µg/L, respectively) collected in the Port of Gdynia and in landfill leachates (LLs) (up to 536 µg/L and up to 2202 µg/L, respectively) from a MSWP located near Gdynia. In particular, the presence of reprotoxic di(2-ethylhexyl) phthalate (DEHP, up to 536 µg/L in LLs and up to 738 µg/L in RMT-WWs) requires further action because if this compound, as well as other PAEs and BPA, is not degraded by activated sludge microorganisms, it may reach receiving waters and adversely impact aquatic organisms. Therefore, PAEs and BPA should be removed either during the onsite pretreatment of tested industrial wastewater or during tertiary treatment at municipal wastewater treatment plants (WWTPs, representing end-of-pipe technology). Graphical abstract.


Assuntos
Compostos Benzidrílicos/química , Disruptores Endócrinos , Fenóis/química , Ácidos Ftálicos/química , Águas Residuárias/química , Poluentes Químicos da Água/análise , Disruptores Endócrinos/análise , Esgotos , Resíduos Sólidos , Águas Residuárias/análise , Poluentes Químicos da Água/química
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