Health & Environmental Research Online (HERO)


Ethylbenzene


999 References Were Found:

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Mutagenic products are promoted in the nitrosation of tyramine

Authors: González-Jiménez, M; Arenas-Valgañón, J; García-Santos, M; Calle, E; Casado, J (2017) Food Chemistry 216:60-65. HERO ID: 3491292

[Less] Tyramine is a biogenic compound derived from the decarboxylation of the amino acid tyrosine, and is . . . [More] Tyramine is a biogenic compound derived from the decarboxylation of the amino acid tyrosine, and is therefore present at important concentrations in a broad range of raw and fermented foods. Owing to its chemical properties, tyramine can react with nitrite, a common food additive, in the acidic medium of stomach to form N- and C-nitroso compounds. Since toxicology studies have shown that the product of C-nitrosation of tyramine is mutagenic, in the present article tyramine nitrosation mechanisms have been characterized in order to discern which of them are favoured under conditions similar to those in the human stomach lumen. To determine the kinetic course of nitrosation reactions, a systematic study of the nitrosation of ethylbenzene, phenethylamine, and tyramine was carried out, using UV-visible absorption spectroscopy. The results show that, under conditions mimicking those of the stomach lumen, the most favoured reaction in tyramine is C-nitrosation, which generates mutagenic products.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Toxicity of acidization fluids used in California oil exploration

Authors: Abdullah, K; Malloy, T; Stenstrom, MK; Suffet, IHMel (2017) Toxicological and Environmental Chemistry 99:78-94. HERO ID: 3491297

[Less] There has been considerable public interest regarding the toxicity of chemicals used in hydraulic fracturing, . . . [More] There has been considerable public interest regarding the toxicity of chemicals used in hydraulic fracturing, but little is known about its sister technique, acidizing. Little to no research has been done on what the chemicals of acidization are and what impact they could have on humans and the environment. This paper discusses the differences between three acidizing techniques (acid maintenance, matrix acidization, and acid fracturing) and quantifies the amounts of the chemicals used for each. Washington State's Quick Chemical Assessment Tool is used to identify F-graded toxins, which are known carcinogens, mutagens, reproductive toxins, developmental toxins, endocrine disruptors, or high acute toxicity chemicals. The analysis of the present data shows that there have been over 600 instances of acidizing in urbanized Southern and Central California from April 2013 to August 2015. Although most of the chemicals of acidizing are similar to hydraulic fracturing, those used most frequently are different. There are close to 200 specific chemicals used in acidization, with at least 28 of them being F-graded hazardous chemicals. Some are used frequently in the range of 100-1000 kg per treatment, such as hydrofluoric acid, xylene, diethylene glycol, and ethyl benzene. Close to 90 more chemicals are identified using non-specific names as trade secrets or reported with no quantity. Unlike hydraulic fracturing the chemical concentrations in acidizing are high, ranging from 6% to 18%, and the waste returns can be highly acidic, in the range of pH 0-3. With this paper it is hoped that acidization becomes part of the larger discussion on concerns with oil exploration and be evaluated by appropriate authorities.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Treatment of airborne BTEX by a two-stage biotrickling filter and biofilter, exploiting selected bacterial and fungal consortia

Authors: Raboni, M; Torretta, V; Viotti, P (2017) International Journal of Environmental Science and Technology 14:19-28. HERO ID: 3491298

[Less] The pilot plant fed by a 600-Nm(3) h(-1) waste air flow rate consisted of a water scrubbing pre-treatment . . . [More] The pilot plant fed by a 600-Nm(3) h(-1) waste air flow rate consisted of a water scrubbing pre-treatment followed by a biotrickling filter and a biofilter, in series. The growth of selected bacterial and fungal consortia was promoted through the biotrickling filter and biofilter. Total BTEX levels were detected in a raw waste air stream at an average concentration of 39.07 mg Nm(-3). The whole treatment achieved an average of 96.1 % removal efficiency. This performance led to very low average concentrations of individual BTEX in the final air effluent: 1.07 mg Nm(-3) for benzene, 0.16 mg Nm(-3) for toluene, 0.22 mg Nm(-3) for ethylbenzene and 0.07 mg Nm(-3) for xylene (mix). The performance and stability of both biotrickling filter and biofilter confirmed the effectiveness of the treatment in achieving low concentrations of individual BTEX in the final air effluent, which fully comply with the most stringent toxicological standard and threshold odor concentrations, for the protection of workers and local residents. This result was possible by the complementary and synergistic action of the bacterial and fungal consortia in degrading BTEX.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Environmental risk assessment of toxicity exposure: high-throughput expression profiling

Authors: Hong, JiY; Yu, SoY; Ahn, J; Kim, SY; Kim, G; Kim, Y; Son, SW; Hwang, SY (2016) BioChip Journal 10:74-80. HERO ID: 3367550

[Less] Recently, volatile organic compounds (VOCs) in outdoor air pollution have led to major public health . . . [More] Recently, volatile organic compounds (VOCs) in outdoor air pollution have led to major public health problems and the identification of specific minimally invasive biomarkers for assessing environmental toxicant exposure has become increasingly important. However, research into the human health effects of inhalation exposure to VOCs remains insufficient. Using a microarray based approach, we identified and validated characteristic mRNA expression profiles in the human whole blood of workers exposed to VOCs (toluene, ethylbenzene, and xylene), which were then compared with genomic level expressions in workers not exposed to the toxicants. We surveyed 141 workers working in a chemical production factory, of which 66 were not exposed to VOCs. We identified 4384 characteristic discernible exposure indicator mRNAs for toluene, 1296 for ethylbenzene, and 5821 for xylene. Using these, we were able to discern those subjects from the control group to a higher accuracy, sensitivity, and specificity than when using urinary biomarkers. The results showed that altered levels of mRNA can be a reliable, novel, and minimally invasive biological indicator of occupational exposure to VOCs. Future research directions should consider the adverse effects of exposure to VOCs on epigenetic regulation.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Kinetic Separation of Alkylbenzenes with Metal-organic Framework Compounds

Authors: Sawai, T; Yonehara, T; Sano, M; Suzuki, T; Miyake, T (2016) HERO ID: 3491286

[Less] Metal-organic framework (MOF) compounds consisting of terephthalic acid and cations (Cr3+, In3+, Al3+, . . . [More] Metal-organic framework (MOF) compounds consisting of terephthalic acid and cations (Cr3+, In3+, Al3+, Cu2+ and Zn2+) were prepared by the hydro- and solvo-thermal methods and characterized by XRD, N-2 adsorption desorption isotherm, TG-DTA and PE-SEM. The prepared MOFs were crystalline and phase-pure. MOFs were used as column packings for chromatographic separation of alkylbenzenes. MOFs recognized differences in molecular sizes in addition to boiling points of alkylbenzenes. Activation energy for diffusion in the MOF micropores ranged from 25 to 60 kJ mol(-1). Temperature-programmed XRD measurement in air revealed that no expansion or contraction of MOF frameworks occurred up to 230 degrees C.

Book/Book Chapter
Book/ Chapter

Perception of occupational risk exposure to Xylene, Ethylbenzene and Toluene by workers of furniture industry

Authors: Pedro, M; Dias Teixeira, M (2016) In Arezes, PM; Baptista, JS; Barroso, MP; Carneiro, P; Cordeiro, P; Costa, N; Melo, RB; Miguel, AS; Perestrelo, G (Eds.), Occupational Safety and Hygiene IV (pp. 423-426). London: Taylor & Francis Group. HERO ID: 3491294

[Less] The organic solvents are specific properties of each chemical group that makes other toxicological characteristics, . . . [More] The organic solvents are specific properties of each chemical group that makes other toxicological characteristics, with consequent effects on health. Some substances in paints, varnishes and plugged pores in the furniture surface treatment sector are xylene, toluene and ethylbenzene. The study of perception and risk of occupational exposure to xylene, toluene and ethylbenzene by workers of furniture factories in the districts of Aveiro, Coimbra and Viseu, intends to separately evaluate the perceived risk and real risk of exposure to these chemicals in the workplace. The cross-sectional study using a questionnaire was applied in April and May of 2014 to workers of furniture factories, with a sample of 142 respondents from 28 companies. The results of this study show that 55% use the suction booths without proper maintenance. 49% does not always use protective masks. When the protection masks are used, these are not suitable for organic solvents. They indicated also suffering from upper respiratory tract irritation (45%). The ambient air samples were collected between July and November 2014 were held 108 crops air for the determination of toluene, xylene and ethylbenzene. The results of measurements of concentrations of COV's in different companies showed that the arithmetic mean of certain concentrations was 51 ppm for toluene, ethylbenzene to 23 ppm and 57 ppm for xylene isomers. The workers have no real perception of the risks they are exposed. Environmental levels of xylene and toluene exceed the exposure limits established in Decree Law 24/2012.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Modeling of the Reaction Mechanism of Enzymatic Radical C-C Coupling by Benzylsuccinate Synthase

Authors: Szaleniec, M; Heider, J (2016) International Journal of Molecular Sciences 17:514. HERO ID: 3491290

[Less] Molecular modeling techniques and density functional theory calculations were performed to study the . . . [More] Molecular modeling techniques and density functional theory calculations were performed to study the mechanism of enzymatic radical C-C coupling catalyzed by benzylsuccinate synthase (BSS). BSS has been identified as a glycyl radical enzyme that catalyzes the enantiospecific fumarate addition to toluene initiating its anaerobic metabolism in the denitrifying bacterium Thauera aromatica, and this reaction represents the general mechanism of toluene degradation in all known anaerobic degraders. In this work docking calculations, classical molecular dynamics (MD) simulations, and DFT+D2 cluster modeling was employed to address the following questions: (i) What mechanistic details of the BSS reaction yield the most probable molecular model? (ii) What is the molecular basis of enantiospecificity of BSS? (iii) Is the proposed mechanism consistent with experimental observations, such as an inversion of the stereochemistry of the benzylic protons, syn addition of toluene to fumarate, exclusive production of (R)-benzylsuccinate as a product and a kinetic isotope effect (KIE) ranging between 2 and 4? The quantum mechanics (QM) modeling confirms that the previously proposed hypothetical mechanism is the most probable among several variants considered, although C-H activation and not C-C coupling turns out to be the rate limiting step. The enantiospecificity of the enzyme seems to be enforced by a thermodynamic preference for binding of fumarate in the pro(R) orientation and reverse preference of benzyl radical attack on fumarate in pro(S) pathway which results with prohibitively high energy barrier of the radical quenching. Finally, the proposed mechanism agrees with most of the experimental observations, although the calculated intrinsic KIE from the model (6.5) is still higher than the experimentally observed values (4.0) which suggests that both C-H activation and radical quenching may jointly be involved in the kinetic control of the reaction.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Expression of exosomal and cellular microRNAs: as biomarkers for toluene, ethylbenzene, xylene (TEX) exposure

Authors: Lim, Jhee; Song, MiK; Cho, Y; Kim, W; Han, SOk; Ryu, JaeC (2016) Molecular and Cellular Toxicology 12:359-369. HERO ID: 3491283

[Less] Exosomes, small vesicles released by many cells, are associated with various biological processes and . . . [More] Exosomes, small vesicles released by many cells, are associated with various biological processes and they can potentially be used for prognosis and therapy and as biomarkers of health. Thus, they are gaining attention in toxicological and pathological research. miRNA is also considered as a useful tool to predict health risk caused by environmental toxicants. Volatile organic compounds (VOCs), including toluene (T), xylene (X), and ethylbenzene (E), have been reported to be harmful. Although VOCs are prevalent in the environment, the mechanisms underlying their toxicity are not understood. In this study, a microarray analysis identified 50 miRNAs that were differentially expressed in exosomes and cytosols of HL-60 cell line exposed to three VOCs (TEX). A total of 3,355 putative target genes were classified according to the miRWalk 2.0 database. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of the putative target genes showed a correlation with biological processes involved in the regulation of myeloid leukocyte differentiation, MAPK signaling pathway, and pathways in cancer. In conclusion, this study describes alterations in miRNA expression profiles in response to exposure to VOCs and related toxicity affected by significantly expressed target genes. Moreover, it illustrates the value of exosomes as diagnostic biomarkers of toxicity.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Towards preparative peroxygenase-catalyzed oxyfunctionalization reactions in organic media

Authors: Fernandez-Fueyo, E; Ni, Yan; Baraibar, AG; Alcalde, M; van Langen, LM; Hollmann, F (2016) Journal of Molecular Catalysis B: Enzymatic 134:347-352. HERO ID: 3491307

[Less] The peroxygenase from Agrocybe aegerita (AaeUPO) has been evaluated for stereoselective oxyfunctionalization . . . [More] The peroxygenase from Agrocybe aegerita (AaeUPO) has been evaluated for stereoselective oxyfunctionalization chemistry under non-aqueous reaction conditions.

The stereoselective hydroxylation of ethylbenzene to (R)-1-phenylethanol was performed in neat substrate as reaction medium together with the immobilized biocatalyst and (BuOOH)-Bu-tert as oxidant.

Stability and activity issues still have to be addressed. Nevertheless, gram-scale production of enan-tiopure (R)-1-phenylethanol was achieved with respectable 90,000 turnovers of the biocatalyst. (C) 2016 The Authors. Published by Elsevier B.V.

Book/Book Chapter
Book/ Chapter

Evaluation of the perception of knowledge and occupational exposure to xylene, toluene and ethylbenzene for the furniture industry workers

Authors: Pedroso, M; Dias-Teixeira, M (2016) In Arezes, P (Ed.), Advances in Intelligent Systems and Computing (pp. 533-539). Switzerland: Springer International Publishing. HERO ID: 3491282

[Less] The study of perception and risk of occupational exposure to xylene, toluene and ethylbenzene by workers . . . [More] The study of perception and risk of occupational exposure to xylene, toluene and ethylbenzene by workers of furniture factories in the districts of Aveiro, Coimbra and Viseu, intends to separately evaluate the perceived risk and real risk of exposure to these chemicals in the workplace. The cross-sectional study using a questionnaire was applied in April and May of 2014 to workers of furniture factories, with a sample of 142 respondents from 28 companies. The results of this study show that 55 % use the suction booths without proper maintenance. The ambient air samples were collected between July and November 2014 and held 108 crops of air for the determination of toluene, xylene and ethylbenzene. The results of measurements of concentrations of COV's in different companies showed that the arithmetic mean of certain concentrations was 51 ppm for toluene, ethylbenzene to 23 ppm and 57 ppm for xylene isomers.