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1.
J Environ Manage ; 363: 121343, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38843727

RESUMO

This work presents a novel advanced oxidation process (AOP) for degradation of emerging organic pollutants - benzene, toluene, ethylbenzene and xylenes (BTEXs) in water. A comparative study was performed for sonocavitation assisted ozonation under 40-120 kHz and 80-200 kHz dual frequency ultrasounds (DFUS). Based on the obtained results, the combination of 40-120 kHz i.e., low-frequency US (LFDUS) with O3 exhibited excellent oxidation capacity degrading 99.37-99.69% of BTEXs in 40 min, while 86.09-91.76% of BTEX degradation was achieved after 60 min in 80-200 kHz i.e., high-frequency US (HFDUS) combined with O3. The synergistic indexes determined using degradation rate constants were found as 7.86 and 2.9 for LFDUS/O3 and HFDUS/O3 processes, respectively. The higher extend of BTEX degradation in both processes was observed at pH 6.5 and 10. Among the reactive oxygen species (ROSs), hydroxyl radicals (HO•) were found predominant according to scavenging tests, singlet oxygen also importantly contributed in degradation, while O2•- radicals had a minor contribution. Sulfate (SO42-) ions demonstrated higher inhibitory effect compared to chloride (Cl-) and carbonate (CO32-) ions in both processes. Degradation pathways of BTEX was proposed based on the intermediates identified using GC-MS technique.


Assuntos
Derivados de Benzeno , Benzeno , Ozônio , Poluentes Químicos da Água , Xilenos , Ozônio/química , Xilenos/química , Derivados de Benzeno/química , Benzeno/química , Poluentes Químicos da Água/química , Tolueno/química , Oxirredução , Água/química , Espécies Reativas de Oxigênio/química , Purificação da Água/métodos
2.
Bioresour Technol ; 405: 130926, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38824970

RESUMO

Volatile organic compounds emitted from landfills posed adverse effect on health. In this study, gaseous benzene was biologically treated using an in-situ biofilter without air pump. Its performance was investigated and the removal efficiency of benzene reached over 90 %. The decrease in the average benzene concentration was consistent with first-order reaction kinetics. Mycolicibacterium dominated the bacterial consortium (41-57 %) throughout the degradation. Annotation of genes by metagenomic analysis helped to deduce the degradation pathways (benzene degradation, catechol ortho-cleavage and meta-cleavage) and to reveal the contribution of different species to the degradation process. In total, 21 kinds of key genes and 13 enzymes were involved in the three modules of benzene transformation. Mycolicibacter icosiumassiliensis and Sphingobium sp. SCG-1 carried multiple functional genes critically involved in benzene biodegradation. These findings provide technical and theoretical support for the in-situ bioremediation of benzene-contaminated soil and waste gas reduction in landfills.


Assuntos
Benzeno , Biodegradação Ambiental , Poliuretanos , Benzeno/metabolismo , Poliuretanos/química , Filtração , Gases
3.
Sci Rep ; 14(1): 13169, 2024 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849491

RESUMO

The ability of indoor plants to purify benzene pollution is the basic basis for the selection of plants for ecological remediation of indoor benzene pollution. In this study, the purification rate and the purification amount per unit leaf area of 13 test plants at three benzene concentrations were determined by indoor fumigation experiments, and the benzene absorption and purification abilityability of indoor plants were comprehensively evaluated. The results showed that (1) there was a significant correlation between benzene concentration and purification rate and purification amount per unit leaf area. (2) At the three concentrations, Spathiphyllum floribundum showed the highest purification rate and Sansevieria trifasciata var. laurentii showed the highest purification per unit leaf area. (3) The combined results showed that Sansevieria trifasciata var. laurentii, Spathiphyllum floribundum and Aloe arborescens were the strongest absorbers and purifiers, while Podocarpus nagi and Anthurium andraeanum 'Pink champin' had the weakest absorption and purification capacity. The results of this study provide a theoretical basis and reference for the selection of plants with strong capacities to adsorb and purify benzene pollution in indoor air.


Assuntos
Poluição do Ar em Ambientes Fechados , Benzeno , Benzeno/isolamento & purificação , Poluição do Ar em Ambientes Fechados/análise , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/isolamento & purificação , Plantas/química , Folhas de Planta/química , Biodegradação Ambiental , Adsorção
4.
PeerJ ; 12: e17452, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38903883

RESUMO

Background: Conventional biofilters, which rely on bacterial activity, face challenges in eliminating hydrophobic compounds, such as aromatic compounds. This is due to the low solubility of these compounds in water, which makes them difficult to absorb by bacterial biofilms. Furthermore, biofilter operational stability is often hampered by acidification and drying out of the filter bed. Methods: Two bioreactors, a bacterial biofilter (B-BF) and a fungal-bacterial coupled biofilter (F&B-BF) were inoculated with activated sludge from the secondary sedimentation tank of the Sinopec Yangzi Petrochemical Company wastewater treatment plant located in Nanjing, China. For approximately 6 months of operation, a F&B-BF was more effective than a B-BF in eliminating a gas-phase mixture containing benzene, toluene, ethylbenzene, and para-xylene (BTEp-X). Results: After operating for four months, the F&B-BF showed higher removal efficiencies for toluene (T), ethylbenzene (E), benzene (B), and para-X (p-Xylene), at 96.9%, 92.6%, 83.9%, and 83.8%, respectively, compared to those of the B-BF (90.1%, 78.7%, 64.8%, and 59.3%). The degradation activity order for B-BF and F&B-BF was T > E > B > p-X. Similarly, the rates of mineralization for BTEp-X in the F&B-BF were 74.9%, 66.5%, 55.3%, and 45.1%, respectively, which were higher than those in the B-BF (56.5%, 50.8%, 43.8%, and 30.5%). Additionally, the F&B-BF (2 days) exhibited faster recovery rates than the B-BF (5 days). Conclusions: It was found that a starvation protocol was beneficial for the stable operation of both the B-BF and F&B-BF. Community structure analysis showed that the bacterial genus Pseudomonas and the fungal genus Phialophora were both important in the degradation of BTEp-X. The fungal-bacterial consortia can enhance the biofiltration removal of BTEp-X vapors.


Assuntos
Bactérias , Derivados de Benzeno , Reatores Biológicos , Filtração , Fungos , Xilenos , Xilenos/metabolismo , Xilenos/química , Filtração/métodos , Fungos/metabolismo , Derivados de Benzeno/metabolismo , Reatores Biológicos/microbiologia , Bactérias/metabolismo , Biodegradação Ambiental , Tolueno/metabolismo , Benzeno/metabolismo , China , Biofilmes
5.
Chemosphere ; 361: 142551, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38852280

RESUMO

The fate of volatile organic compounds (VOC) vapors in the unsaturated zone is the basis for evaluating the natural attenuation potential and vapor intrusion risk. Microcosm and column experiments were conducted to study the effects chemical speciation and soil types/properties on the fate of petroleum VOCs in unsaturated zone. The biodegradation and total attenuation rates of the seven VOCs obtained by microcosm experiments in black soil and yellow earth were also generally higher than those in floodplain soil, lateritic red earth, and quartz sand. The VOC vapors in floodplain soil, lateritic red earth, and quartz sand showed slow total attenuation rates (<0.3 d-1). N-pentane, methylcyclopentane, and methylcyclohexane showed lower biodegradation rates than octane and three monoaromatic hydrocarbons. Volatilization into the atmosphere and biodegradation are two important natural attenuation paths for VOCs in unsaturated soil columns. The volatilization loss fractions of different volatile hydrocarbons in all five unsaturated soils were generally in the order: n-pentane (93.5%-97.8%) > methylcyclopentane (77.2%-85.5%) > methylcyclohexane (53.5%-69.2%) > benzene (17.1%-73.3%) > toluene (0-45.7%) > octane (1.9%-34.2%) > m-xylene (0-5.7%). The fractions by volatilization into the atmosphere of all seven hydrocarbons in quartz sand, lateritic red earth, and floodplain soil were close and higher compared to the yellow earth and black soil. Overall, this study illustrated the important roles chemical speciation and soil properties in determining the vapor-phase transport and natural attenuation of VOCs in the unsaturated zone.


Assuntos
Biodegradação Ambiental , Petróleo , Poluentes do Solo , Solo , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química , Petróleo/análise , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/química , Adsorção , Volatilização , Pentanos/química , Pentanos/análise , Octanos/química , Tolueno/química , Tolueno/análise , Benzeno/análise , Benzeno/química
6.
Chemosphere ; 361: 142490, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38821131

RESUMO

Aromatic hydrocarbons like benzene, toluene, xylene, and ethylbenzene (BTEX) can escape into the environment from oil and gas operations and manufacturing industries posing significant health risks to humans and wildlife. Unlike conventional clean-up methods used, biological approaches such as bioremediation can provide a more energy and labour-efficient and environmentally friendly option for sensitive areas such as nature reserves and cities, protecting biodiversity and public health. BTEX contamination is often concentrated in the subsurface of these locations where oxygen is rapidly depleted, and biodegradation relies on anaerobic processes. Thus, it is critical to understand the anaerobic biodegradation characteristics as it has not been explored to a major extent. This review presents novel insights into the degradation mechanisms under anaerobic conditions and presents a detailed description and interconnection between them. BTEX degradation can follow four activation mechanisms: hydroxylation, carboxylation, methylation, and fumarate addition. Hydroxylation is one of the mechanisms that explains the transformation of benzene into phenol, toluene into benzyl alcohol or p-cresol, and ethylbenzene into 1-phenylethanol. Carboxylation to benzoate is thought to be the primary mechanism of degradation for benzene. Despite being poorly understood, benzene methylation has been also reported. Moreover, fumarate addition is the most widely reported mechanism, present in toluene, ethylbenzene, and xylene degradation. Further research efforts are required to better elucidate new and current alternative catabolic pathways. Likewise, a comprehensive analysis of the enzymes involved as well as the development of advance tools such as omic tools can reveal bottlenecks degradation steps and create more effective on-site strategies to address BTEX pollution.


Assuntos
Derivados de Benzeno , Benzeno , Biodegradação Ambiental , Tolueno , Xilenos , Anaerobiose , Derivados de Benzeno/metabolismo , Benzeno/metabolismo , Tolueno/metabolismo , Xilenos/metabolismo , Poluentes Ambientais/metabolismo , Hidrocarbonetos Aromáticos/metabolismo
7.
Eur Rev Med Pharmacol Sci ; 28(8): 3135-3143, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38708472

RESUMO

OBJECTIVE: Benzene is one of the major carcinogenic factors that can affect liver, kidneys, and lungs. Chronic inhalation of benzene vapor by petrol stations workers has been shown to have an impact on hematological parameters; thus, the present study aimed to investigate the effect of benzene exposure on petrol station workers. SUBJECTS AND METHODS: The study involved 99 participants, 50 of whom have been exposed to benzene and 49 of whom have not (control). A 5 ml blood sample in an ethylenediaminetetraacetic acid (EDTA) anticoagulant tube was collected from each subject, and a complete blood count test was used to test hematological parameters. RESULTS: The current study showed a significant decrease in red blood cells, packed cell volume, and hemoglobin in the exposed group compared to the control group. However, the amount of white blood cells was significantly increased (p < 0.0001) in the exposed group compared to the control group. Notably, there was no significant difference in platelet counts between the two groups. In terms of exposure time, subjects who have been exposed to benzene for more than a year and fewer than 10 years showed a significant decrease (p < 0.05) in RBCs indices and a significant increase (p < 0.0001) in WBCs compared to those in the control group CONCLUSIONS: Thus, the findings indicated that significant differences in hematological parameters were found in workers who were exposed to benzene compared to those who had not been exposed.


Assuntos
Benzeno , Exposição Ocupacional , Humanos , Exposição Ocupacional/efeitos adversos , Benzeno/toxicidade , Adulto , Masculino , Contagem de Células Sanguíneas , Hemoglobinas/análise , Hemoglobinas/metabolismo , Pessoa de Meia-Idade
8.
Front Public Health ; 12: 1355739, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38807987

RESUMO

Objectives: To assess leukemia risk in occupational populations exposed to low levels of benzene. Methods: Leukemia incidence data from the Chinese Benzene Cohort Study were fitted using the Linearized multistage (LMS) model. Individual benzene exposure levels, urinary S-phenylmercapturic acid (S-PMA) and trans, trans-muconic acid (t, t-MA) were measured among 98 benzene-exposed workers from factories in China. Subjects were categorized into four groups by rounding the quartiles of cumulative benzene concentrations (< 3, 3-5, 5-12, ≥12 mg/m3·year, respectively). The risk of benzene-induced leukemia was assessed using the LMS model, and the results were validated using the EPA model and the Singapore semi-quantitative risk assessment model. Results: The leukemia risks showed a positive correlation with increasing cumulative concentration in the four exposure groups (excess leukemia risks were 4.34, 4.37, 4.44 and 5.52 × 10-4, respectively; Ptrend < 0.0001) indicated by the LMS model. We also found that the estimated leukemia risk using urinary t, t-MA in the LMS model was more similar to those estimated by airborne benzene compared to S-PMA. The leukemia risk estimated by the LMS model was consistent with both the Singapore semi-quantitative risk assessment model at all concentrations and the EPA model at high concentrations (5-12, ≥12 mg/m3·year), while exceeding the EPA model at low concentrations (< 3 and 3-5 mg/m3·year). However, in all four benzene-exposed groups, the leukemia risks estimated by these three models exceeded the lowest acceptable limit for carcinogenic risk set by the EPA at 1 × 10-6. Conclusion: This study demonstrates the utility of the LMS model derived from the Chinese benzene cohort in assessing leukemia risk associated with low-level benzene exposure, and suggests that leukemia risk may occur at cumulative concentrations below 3 mg/m3·year.


Assuntos
Benzeno , Leucemia , Exposição Ocupacional , Ácido Sórbico , Benzeno/toxicidade , Humanos , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Medição de Risco , Leucemia/induzido quimicamente , Leucemia/epidemiologia , China/epidemiologia , Masculino , Adulto , Ácido Sórbico/análogos & derivados , Ácido Sórbico/análise , Pessoa de Meia-Idade , Acetilcisteína/urina , Acetilcisteína/análogos & derivados , Feminino , Estudos de Coortes , Incidência
9.
Chemosphere ; 359: 142247, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38705410

RESUMO

Mn or Co supported CeO2 fiber catalysts were synthesized following a biotemplating route and evaluated in soot combustion and benzene total oxidation. The catalysts were characterized by SEM, EDX, N2 physisorption, FTIR-ATR, XRD, RAMAN and XPS. SEM results confirmed that the "twisted ribbon" morphology of the biotemplate was mostly maintained. XRD and Raman showed that Mn and Co cations partially insert into ceria lattice and also segregate at the surface of the fibers. XPS allowed to determine that both set of catalysts exhibit Ce3+ and Ce4+ species, in addition to adsorbed and lattice oxygen. Also, the average oxidation state (AOS) of surface Mn could be calculated. Compared to bare Fib Ce, the performances for both reactions were improved for the supported catalysts, except from the catalyst with lowest Mn content for soot combustion. The catalytic activity was discussed in terms of the physicochemical features of the supported catalysts.


Assuntos
Benzeno , Cério , Cobalto , Manganês , Oxirredução , Fuligem , Cério/química , Benzeno/química , Catálise , Manganês/química , Cobalto/química , Fuligem/química
10.
Chemosphere ; 359: 142344, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38754484

RESUMO

Burning incenses and scented candles may provide harmful chemicals. Although many studies have evaluated volatile organic chemicals emitted by their use and related health risks, extension of our understanding for guiding appropriate use under various use conditions is necessary. In this study, emission characteristics of commercial incenses and scented candles were evaluated in a laboratory chamber using real-time measurement and the time-weighted average exposure concentrations of monoaromatic compounds and monoterpenes were assessed using passive samplers while volunteers living in a studio apartment use them. After burning incense, the average levels of benzene increased from 1.4 to 100 µg m-3. The presence of a wood core in commercial incense products was the main cause of high benzene emission by burning them although the increase in benzene was also influenced by factors such as the brand of the products, the number of incense sticks burned, the duration of each burning session, and ventilation period. Electrical warming of scented candles increased the levels of monoterpenes by factors of 16-30 on average. Considering the emission characteristics found in this study, exposure to benzene and monoterpenes could be mitigated by cautious use of those products in residential areas.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Benzeno , Monitoramento Ambiental , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/análise , Poluição do Ar em Ambientes Fechados/análise , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Monitoramento Ambiental/métodos , Benzeno/análise , Poluentes Atmosféricos/análise , Habitação , Humanos , Monoterpenos/análise , Odorantes/análise
11.
Environ Int ; 188: 108755, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38772206

RESUMO

The rapid advance in shotgun metagenome sequencing has enabled us to identify uncultivated functional microorganisms in polluted environments. While aerobic petrochemical-degrading pathways have been extensively studied, the anaerobic mechanisms remain less explored. Here, we conducted a study at a petrochemical-polluted groundwater site in Henan Province, Central China. A total of twelve groundwater monitoring wells were installed to collect groundwater samples. Benzene appeared to be the predominant pollutant, detected in 10 out of 12 samples, with concentrations ranging from 1.4 µg/L to 5,280 µg/L. Due to the low aquifer permeability, pollutant migration occurred slowly, resulting in relatively low benzene concentrations downstream within the heavily polluted area. Deep metagenome sequencing revealed Proteobacteria as the dominant phylum, accounting for over 63 % of total abundances. Microbial α-diversity was low in heavily polluted samples, with community compositions substantially differing from those in lightly polluted samples. dmpK encoding the phenol/toluene 2-monooxygenase was detected across all samples, while the dioxygenase bedC1 was not detected, suggesting that aerobic benzene degradation might occur through monooxygenation. Sequence assembly and binning yielded 350 high-quality metagenome-assembled genomes (MAGs), with 30 MAGs harboring functional genes associated with aerobic or anaerobic benzene degradation. About 80 % of MAGs harboring functional genes associated with anaerobic benzene degradation remained taxonomically unclassified at the genus level, suggesting that our current database coverage of anaerobic benzene-degrading microorganisms is very limited. Furthermore, two genes integral to anaerobic benzene metabolism, i.e, benzoyl-CoA reductase (bamB) and glutaryl-CoA dehydrogenase (acd), were not annotated by metagenome functional analyses but were identified within the MAGs, signifying the importance of integrating both contig-based and MAG-based approaches. Together, our efforts of functional annotation and metagenome binning generate a robust blueprint of microbial functional potentials in petrochemical-polluted groundwater, which is crucial for designing proficient bioremediation strategies.


Assuntos
Benzeno , Biodegradação Ambiental , Água Subterrânea , Redes e Vias Metabólicas , Poluentes Químicos da Água , Água Subterrânea/microbiologia , Água Subterrânea/química , Benzeno/metabolismo , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/análise , China , Metagenoma , Bactérias/metabolismo , Bactérias/genética , Bactérias/classificação , Petróleo/metabolismo
12.
Crit Rev Toxicol ; 54(4): 252-289, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38753561

RESUMO

INTRODUCTION: Causal epidemiology for regulatory risk analysis seeks to evaluate how removing or reducing exposures would change disease occurrence rates. We define interventional probability of causation (IPoC) as the change in probability of a disease (or other harm) occurring over a lifetime or other specified time interval that would be caused by a specified change in exposure, as predicted by a fully specified causal model. We define the closely related concept of causal assigned share (CAS) as the predicted fraction of disease risk that would be removed or prevented by a specified reduction in exposure, holding other variables fixed. Traditional approaches used to evaluate the preventable risk implications of epidemiological associations, including population attributable fraction (PAF) and the Bradford Hill considerations, cannot reveal whether removing a risk factor would reduce disease incidence. We argue that modern formal causal models coupled with causal artificial intelligence (CAI) and realistically partial and imperfect knowledge of underlying disease mechanisms, show great promise for determining and quantifying IPoC and CAS for exposures and diseases of practical interest. METHODS: We briefly review key CAI concepts and terms and then apply them to define IPoC and CAS. We present steps to quantify IPoC using a fully specified causal Bayesian network (BN) model. Useful bounds for quantitative IPoC and CAS calculations are derived for a two-stage clonal expansion (TSCE) model for carcinogenesis and illustrated by applying them to benzene and formaldehyde based on available epidemiological and partial mechanistic evidence. RESULTS: Causal BN models for benzene and risk of acute myeloid leukemia (AML) incorporating mechanistic, toxicological and epidemiological findings show that prolonged high-intensity exposure to benzene can increase risk of AML (IPoC of up to 7e-5, CAS of up to 54%). By contrast, no causal pathway leading from formaldehyde exposure to increased risk of AML was identified, consistent with much previous mechanistic, toxicological and epidemiological evidence; therefore, the IPoC and CAS for formaldehyde-induced AML are likely to be zero. CONCLUSION: We conclude that the IPoC approach can differentiate between likely and unlikely causal factors and can provide useful upper bounds for IPoC and CAS for some exposures and diseases of practical importance. For causal factors, IPoC can help to estimate the quantitative impacts on health risks of reducing exposures, even in situations where mechanistic evidence is realistically incomplete and individual-level exposure-response parameters are uncertain. This illustrates the strength that can be gained for causal inference by using causal models to generate testable hypotheses and then obtaining toxicological data to test the hypotheses implied by the models-and, where necessary, refine the models. This virtuous cycle provides additional insight into causal determinations that may not be available from weight-of-evidence considerations alone.


Assuntos
Benzeno , Formaldeído , Leucemia Mieloide Aguda , Humanos , Benzeno/toxicidade , Leucemia Mieloide Aguda/epidemiologia , Leucemia Mieloide Aguda/induzido quimicamente , Formaldeído/toxicidade , Causalidade , Probabilidade , Medição de Risco , Exposição Ambiental , Fatores de Risco
13.
Biomed Environ Sci ; 37(4): 341-353, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38727157

RESUMO

Objective: Hydroquinone (HQ), one of the phenolic metabolites of benzene, is widely recognized as an important participant in benzene-induced hematotoxicity. However, there are few relevant proteomics in HQ-induced hematotoxicity and the mechanism hasn't been fully understood yet. Methods: In this study, we treated K562 cells with 40 µmol/L HQ for 72 h, examined and validated protein expression changes by Label-free proteomic analysis and Parallel reaction monitoring (PRM), and performed bioinformatics analysis to identify interaction networks. Results: One hundred and eighty-seven upregulated differentially expressed proteins (DEPs) and 279 downregulated DEPs were identified in HQ-exposed K562 cells, which were involved in neutrophil-mediated immunity, blood microparticle, and other GO terms, as well as the lysosome, metabolic, cell cycle, and cellular senescence-related pathways. Focusing on the 23 DEGs and 5 DEPs in erythroid differentiation-related pathways, we constructed the network of protein interactions and determined 6 DEPs (STAT1, STAT3, CASP3, KIT, STAT5B, and VEGFA) as main hub proteins with the most interactions, among which STATs made a central impact and may be potential biomarkers of HQ-induced hematotoxicity. Conclusion: Our work reinforced the use of proteomics and bioinformatic approaches to advance knowledge on molecular mechanisms of HQ-induced hematotoxicity at the protein level and provide a valuable basis for further clarification.


Assuntos
Benzeno , Hemolíticos , Proteoma , Proteoma/metabolismo , Proteômica , Benzeno/toxicidade , Células K562 , Humanos , Testes de Toxicidade/métodos , Hemolíticos/toxicidade
14.
Environ Sci Technol ; 58(19): 8380-8392, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38691504

RESUMO

A comprehensive understanding of the full volatility spectrum of organic oxidation products from the benzene series precursors is important to quantify the air quality and climate effects of secondary organic aerosol (SOA) and new particle formation (NPF). However, current models fail to capture the full volatility spectrum due to the absence of important reaction pathways. Here, we develop a novel unified model framework, the integrated two-dimensional volatility basis set (I2D-VBS), to simulate the full volatility spectrum of products from benzene series precursors by simultaneously representing first-generational oxidation, multigenerational aging, autoxidation, dimerization, nitrate formation, etc. The model successfully reproduces the volatility and O/C distributions of oxygenated organic molecules (OOMs) as well as the concentrations and the O/C of SOA over wide-ranging experimental conditions. In typical urban environments, autoxidation and multigenerational oxidation are the two main pathways for the formation of OOMs and SOA with similar contributions, but autoxidation contributes more to low-volatility products. NOx can reduce about two-thirds of OOMs and SOA, and most of the extremely low-volatility products compared to clean conditions, by suppressing dimerization and autoxidation. The I2D-VBS facilitates a holistic understanding of full volatility product formation, which helps fill the large gap in the predictions of organic NPF, particle growth, and SOA formation.


Assuntos
Benzeno , Benzeno/química , Compostos Orgânicos/química , Oxirredução , Aerossóis , Volatilização , Poluentes Atmosféricos , Modelos Teóricos
15.
Arch Toxicol ; 98(7): 1991-2005, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38600397

RESUMO

Benzene is used worldwide as a major raw material in a number of industrial processes and also a potent airborne pollutant emitted from traffic exhaust fume. The present systematic review aimed to identify potential associations between genetic polymorphisms and occupational benzene-induced genotoxicity. For this purpose, a total of 22 selected studies were carefully analysed. Our results revealed a positive relation between gene polymorphism and genotoxicity in individuals exposed to benzene, since 17 studies (out of 22) observed positive relations between genotoxicity and polymorphisms in xenobiotics metabolizing genes influencing, therefore, individuals' susceptibility to genomic damage induced by benzene. In other words, individuals with some genotypes may show increase or decrease DNA damage and/or higher or lower DNA-repair potential. As for the quality assessment, 17 studies (out of 22) were categorized as Strong or Moderate and, therefore, we consider our findings to be trustworthy. Taken together, such findings are consistent with the notion that benzene induces genotoxicity in mammalian cells being strongly dependent on the genetic polymorphism. Certainly, such findings are important for clarifying the role of biomarkers related to genotoxicity in human biomonitoring studies.


Assuntos
Benzeno , Dano ao DNA , Exposição Ocupacional , Polimorfismo Genético , Humanos , Benzeno/toxicidade , Exposição Ocupacional/efeitos adversos , Dano ao DNA/efeitos dos fármacos , Poluentes Ocupacionais do Ar/toxicidade , Mutagênicos/toxicidade
16.
ACS Sens ; 9(4): 1906-1915, 2024 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-38565844

RESUMO

As a carcinogenic and highly neurotoxic hazardous gas, benzene vapor is particularly difficult to be distinguished in BTEX (benzene, toluene, ethylbenzene, xylene) atmosphere and be detected in low concentrations due to its chemical inertness. Herein, we develop a depth-related pore structure in Cu-TCPP-Cu to thermodynamically and kinetically enhance the adsorption of benzene vapor and realize the detection of ultralow-temperature benzene gas. We find that the in-plane π electronic nature and proper pore sizes in Cu-TCPP-Cu can selectively induce the adsorption and diffusion of BTEX. Interestingly, the theoretical calculations (including density functional theory (DFT) and grand canonical Monte Carlo (GCMC) simulations) exhibit that benzene molecules are preferred to adsorb and array as a consecutive arrangement mode in the Cu-TCPP-Cu pore, while the TEX (toluene, ethylbenzene, xylene) dominate the jumping arrangement model. The differences in distribution behaviors can allow adsorption and diffusion of more benzene molecules within limited room. Furthermore, the optimal pore-depth range (60-65 nm) of Cu-TCPP-Cu allows more exposure of active sites and hinders the gas-blocking process. The optimized sensor exhibits ultrahigh sensitivity to benzene vapor (155 Hz/µg@1 ppm), fast response time (less than 10 s), extremely low limit of detection (65 ppb), and excellent selectivity (83%). Our research thus provides a fundamental understanding to design and optimize two-dimensional metal-organic framework (MOF)-based gas sensors.


Assuntos
Benzeno , Cobre , Limite de Detecção , Estruturas Metalorgânicas , Termodinâmica , Benzeno/análise , Benzeno/química , Cobre/química , Estruturas Metalorgânicas/química , Adsorção , Cinética , Teoria da Densidade Funcional , Gases/análise , Gases/química
17.
J Occup Environ Hyg ; 21(5): 353-364, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38560919

RESUMO

Structural firefighters are exposed to a complex set of contaminants and combustion byproducts, including volatile organic compounds (VOCs). Additionally, recent studies have found structural firefighters' skin may be exposed to multiple chemical compounds via permeation or penetration of chemical byproducts through or around personal protective equipment (PPE). This mannequin-based study evaluated the effectiveness of four different PPE conditions with varying contamination control measures (incorporating PPE interface design features and particulate blocking materials) to protect against ingress of several VOCs in a smoke exposure chamber. We also investigated the effectiveness of long-sleeve base layer clothing to provide additional protection against skin contamination. Outside gear air concentrations were measured from within the smoke exposure chamber at the breathing zone, abdomen, and thigh heights. Personal air concentrations were collected from mannequins under PPE at the same general heights and under the base layer at abdomen and thigh heights. Sampled contaminants included benzene, toluene, styrene, and naphthalene. Results suggest that VOCs can readily penetrate the ensembles. Workplace protection factors (WPFs) were near one for benzene and toluene and increased with increasing molecular weight of the contaminants. WPFs were generally lower under hoods and jackets compared to under pants. For all PPE conditions, the pants appeared to provide the greatest overall protection against ingress of VOCs, but this may be due in part to the lower air concentrations toward the floor (and cuffs of pants) relative to the thigh-height outside gear concentrations used in calculating the WPFs. Providing added interface control measures and adding particulate-blocking materials appeared to provide a protective benefit against less-volatile chemicals, like naphthalene and styrene.


Assuntos
Poluentes Ocupacionais do Ar , Bombeiros , Naftalenos , Exposição Ocupacional , Roupa de Proteção , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/análise , Exposição Ocupacional/prevenção & controle , Exposição Ocupacional/análise , Poluentes Ocupacionais do Ar/análise , Humanos , Benzeno/análise , Tolueno/análise , Equipamento de Proteção Individual , Estireno/análise , Manequins , Fumaça/análise , Local de Trabalho
18.
Environ Sci Pollut Res Int ; 31(21): 31443-31454, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38630400

RESUMO

Benzene, toluene, ethylbenzene, and xylene (BTEX) are ubiquitous in the environment, and all of them can cause neurotoxicity. However, the association between BTEX exposure and dyslexia, a disorder with language network-related regions in left hemisphere affected, remains unclear. We aimed to assess the relationship between BTEX exposure and dyslexic odds among school-aged children. A case-control study, including 355 dyslexics and 390 controls from three cities in China, was conducted. Six BTEX metabolites were measured in their urine samples. Logistic regression model was used to explore the association between the BTEX metabolites and the dyslexic odds. Urinary trans,trans-muconic acid (MU: a metabolite of benzene) was significantly associated with an increased dyslexic odds [odds ratio (OR) = 1.23, 95% confidence interval (CI): 1.01, 1.50], and the adjusted OR of the dyslexic odds in the third tertile was 1.72 (95% CI: 1.06, 2.77) compared to that in the lowest tertile regarding urinary MU concentration. Furthermore, the association between urinary MU level and the dyslexic odds was more pronounced among children from low-income families based on stratified analyses. Urinary metabolite levels of toluene, ethylbenzene, and xylene were not found to be associated with the dyslexic odds. In summary, elevated MU concentrations may be associated with an increased dyslexic odds. We should take measures to reduce MU related exposure among children, particularly those with low family income.


Assuntos
Derivados de Benzeno , Benzeno , Dislexia , Tolueno , Xilenos , Humanos , Criança , Xilenos/urina , Tolueno/urina , Masculino , Derivados de Benzeno/urina , China , Feminino , Dislexia/urina , Estudos de Casos e Controles , Exposição Ambiental , Ácido Sórbico/análogos & derivados , Ácido Sórbico/metabolismo , Razão de Chances
19.
CNS Neurosci Ther ; 30(4): e14718, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38615366

RESUMO

AIMS: Classification of spinal muscular atrophy (SMA) is associated with the clinical prognosis; however, objective classification markers are scarce. This study aimed to identify metabolic markers in the cerebrospinal fluid (CSF) of children with SMA types II and III. METHODS: CSF samples were collected from 40 patients with SMA (27 with type II and 13 with type III) and analyzed for metabolites. RESULTS: We identified 135 metabolites associated with SMA types II and III. These were associated with lysine degradation and arginine, proline, and tyrosine metabolism. We identified seven metabolites associated with the Hammersmith Functional Motor Scale: 4-chlorophenylacetic acid, adb-chminaca,(+/-)-, dodecyl benzenesulfonic acid, norethindrone acetate, 4-(undecan-5-yl) benzene-1-sulfonic acid, dihydromaleimide beta-d-glucoside, and cinobufagin. Potential typing biomarkers, N-cyclohexylformamide, cinobufagin, cotinine glucuronide, N-myristoyl arginine, 4-chlorophenylacetic acid, geranic acid, 4-(undecan-5-yl) benzene, and 7,8-diamino pelargonate, showed good predictive performance. Among these, N-myristoyl arginine was unaffected by the gene phenotype. CONCLUSION: This study identified metabolic markers are promising candidate prognostic factors for SMA. We also identified the metabolic pathways associated with the severity of SMA. These assessments can help predict the outcomes of screening SMA classification biomarkers.


Assuntos
Fenilacetatos , Atrofias Musculares Espinais da Infância , Criança , Humanos , Benzeno , Metabolômica , Arginina
20.
Bioresour Technol ; 400: 130650, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38570099

RESUMO

Illustrating the biodegradation processes of multi-component volatile organic compounds (VOCs) will expedite the implication of biotechnology in purifying industrial exhaust. Here, performance shifts of microbial fuel cell and biotrickling filter combined system (MFC-BTF) are investigated for removing single and dual components of toluene and benzene. Synchronous removal of toluene (95 %) and benzene (97 %) are achieved by MFC-BTF accompanied with the output current of 0.41 mA. Elevated content of extracellular polymeric substance facilitates the mass transfer of benzene with the presence of toluene. Strains of Bacteroidota, Proteobacteria and Chloroflexi contribute to the removal of dual components VOCs. Empty bed reaction time and the VOCs concentration are the important factors influencing their dissolution in the system. The biodegradation of toluene and benzene proceeds with 2-hydroxymuconic semialdehyde and o-hydroxybenzoic acid as the main intermediates. These results provide a comprehensive understanding of multi-component VOCs removal by MFC-BTF and guide the system design, optimization, and scale-up.


Assuntos
Benzeno , Biodegradação Ambiental , Fontes de Energia Bioelétrica , Tolueno , Tolueno/metabolismo , Benzeno/metabolismo , Filtração/métodos , Compostos Orgânicos Voláteis/metabolismo , Gases/metabolismo
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