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1.
PLoS One ; 19(6): e0304712, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38923995

RESUMO

The working conditions of heavy-duty trucks are very complicated as the diesel shaking and resonance problems, which causes weld tears, separators to fall off, and other failures occur. Through experiments and finite element simulation, the natural frequency and vibration mode of a given 400 L diesel tank were calculated to study the influences of structural parameters such as the fill ratio (0.1-0.9), the number of baffle plates (0, 1, 2), the spacing of the plates (240 mm, 400 mm, 560 mm) and the aperture (38 mm, 78 mm, 118 mm) on the modal parameters with the wet mode method. The results of the hammering mode test and the simulation modal analysis agree well with the maximum error is 4.8%; the natural frequency of the diesel tank will increase with fill ratio decrease; the increase of the baffle plate number (0, 1, 2) can effectively increase the first-order natural frequency of the diesel tank, but the change of the natural frequency is not obvious on the higher order; the higher plates spacing has a smaller natural frequency; increasing the aperture will highly increase the natural frequency, 188 mm has better vibration safety.


Assuntos
Veículos Automotores , Vibração , Vibração/efeitos adversos , Gasolina , Humanos , Desenho de Equipamento
2.
Environ Sci Pollut Res Int ; 31(27): 39650-39662, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38829501

RESUMO

In order to replace conventional diesel, biodiesel from various feedstocks is being researched for diesel engines. This study explores novel biodiesel blends produced from unconventional resources such as mentha piperita (peppermint), pontederia crassipes (water hyacinth), tamarindus indica (tamarind), and trichosanthes cucumerina (snake gourd) to assess the outcomes of a diesel engine. The fuel samples are designated as MP20, PC20, TC20, and TI20, which consist of 80% biodiesel and 20% diesel. The assessment is carried out on a four-stroke, one-cylinder diesel engine that is water-cooled and set to operate at 1500 rpm with a 17.5 compression ratio under various engine loading scenarios with quarter-incremental loading from one-fourth to full loading conditions. The fuel samples are injected with 220 bar injection pressure into the combustion chamber 23° before TDC. An extensive analysis of engine parameters is performed using engine configuration, fuel characteristics, and applied boundary conditions. This comprises brake-specific energy consumption (BSEC), fuel consumption (BSFC), thermal efficiency (BTE), cylinder pressure (CP), heat release rate (HRR), particulate matter (PM), nitrogen oxide (NOx), and carbon dioxide (CO2) emissions. At 100% load, the biodiesel blends show an increase in BSFC (2.8-12.6%) and BSEC (1.1-7.1%) but a minor decrease in CP (0.9-6.9%), HRR (0.8-16.2%), and BTE (1.2-2.9%). For biodiesel blends at full engine load, the emissions of PM (8.9-21.4%), NOx (1.4-16.2%) and CO2 (2.4-7.9%) are all significantly reduced. The results emphasize the distinct benefits of biodiesel blends, demonstrating enhanced engine performance and substantial decreases in emissions, which supports the aim of providing sustainable energy solutions.


Assuntos
Biocombustíveis , Emissões de Veículos , Biocombustíveis/análise , Emissões de Veículos/análise , Gasolina
3.
Environ Sci Technol ; 58(24): 10652-10663, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38829825

RESUMO

Secondary organic aerosol (SOA) formation from gasoline vehicles spanning a wide range of emission types was investigated using an oxidation flow reactor (OFR) by conducting chassis dynamometer tests. Aided by advanced mass spectrometric techniques, SOA precursors, including volatile organic compounds (VOCs) and intermediate/semivolatile organic compounds (I/SVOCs), were comprehensively characterized. The reconstructed SOA produced from the speciated VOCs and I/SVOCs can explain 69% of the SOA measured downstream of an OFR upon 0.5-3 days' OH exposure. While VOCs can only explain 10% of total SOA production, the contribution from I/SVOCs is 59%, with oxygenated I/SVOCs (O-I/SVOCs) taking up 20% of that contribution. O-I/SVOCs (e.g., benzylic or aliphatic aldehydes and ketones), as an obscured source, account for 16% of total nonmethane organic gas (NMOG) emission. More importantly, with the improvement in emission standards, the NMOG is effectively mitigated by 35% from China 4 to China 6, which is predominantly attributed to the decrease of VOCs. Real-time measurements of different NMOG components as well as SOA production further reveal that the current emission control measures, such as advances in engine and three-way catalytic converter (TWC) techniques, are effective in reducing the "light" SOA precursors (i.e., single-ring aromatics) but not for the I/SVOC emissions. Our results also highlight greater effects of O-I/SVOCs to SOA formation than previously observed and the urgent need for further investigation into their origins, i.e., incomplete combustion, lubricating oil, etc., which requires improvements in real-time molecular-level characterization of I/SVOC molecules and in turn will benefit the future design of control measures.


Assuntos
Aerossóis , Gasolina , Emissões de Veículos , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/química , Compostos Orgânicos/química
4.
Ecotoxicol Environ Saf ; 279: 116463, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38749194

RESUMO

The environmental impact of oil spills is a critical concern, particularly pertaining to low sulfur marine diesel (LSMD) and high sulfur fuel oil (HSFO) that are commonly involved in coastal spills. Although transcriptomic biomonitoring of sentinel animals can be a powerful tool for assessing biological effects, conventional methods utilize lethal sampling to examine the liver. As a non-lethal alternative, we have previously shown salmonid caudal fin cyp1a1 is significantly responsive to LSMD-derived toxicants. The present study further investigated the transcriptomic biomonitoring potential of coho salmon smolt caudal fin in comparison to liver tissue in the context of LSMD and HSFO seawater accommodated fraction (seaWAF) exposure in cold-water marine environments. Assessing the toxicity of these seaWAFs involved quantifying polycyclic aromatic hydrocarbon (tPAH50) concentrations and generating gene expression profiles. Initial qPCR analyses revealed significant cyp1a1 response in both liver and caudal fin tissues of both genetic sexes to all seaWAF exposures. RNA-Seq analysis, focusing on the highest LSMD and HSFO seaWAF concentrations (28.4±1.8 and 645.08±146.3 µg/L tPAH50, respectively), revealed distinct tissue-specific and genetic sex-independent transcriptomic responses with an overall enrichment of oxidative stress, cell adhesion, and morphogenesis-related pathways. Remarkably, the caudal fin tissue exhibited transcriptomic response patterns comparable to liver tissue, particularly consistent differential expression of 33 gene transcripts in the liver (independent of sex and oil type) and 44 in the caudal fin. The present work underscores the viability of using the caudal fin as a non-lethal alternative to liver sampling for assessing and tracking oil spill exposure in marine environments.


Assuntos
Nadadeiras de Animais , Citocromo P-450 CYP1A1 , Óleos Combustíveis , Fígado , Poluição por Petróleo , Transcriptoma , Poluentes Químicos da Água , Animais , Fígado/efeitos dos fármacos , Fígado/metabolismo , Poluentes Químicos da Água/toxicidade , Poluição por Petróleo/efeitos adversos , Nadadeiras de Animais/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Masculino , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Óleos Combustíveis/toxicidade , Feminino , Enxofre , Monitoramento Ambiental/métodos , Oncorhynchus kisutch/genética , Gasolina/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Água do Mar/química
5.
Sci Total Environ ; 941: 173390, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38815831

RESUMO

Vehicle exhaust is the primary source of polycyclic aromatic compounds (PACs). Real road tests using a portable vehicle measurement system on light-duty gasoline vehicles and light-duty diesel trucks were conducted to investigate gas- and particle-phase polycyclic aromatic hydrocarbons (PAHs), nitro-PAHs (NPAHs), and oxy-PAHs (OPAHs) in vehicle exhaust with different emission standards, fuel types, and altitudes. The results showed that with the tightening of emission standards, the overall emission factors (EFs) of PACs decreased. Compared with China V diesel vehicles, the emissions of PAHs, OPAHs, and NPAHs from China VI diesel vehicles were 75.1 %, 84.4 %, and 61.2 % lower, respectively. With a ∼100 m increase in altitude, the EFs of PAHs, OPAHs, and NPAHs of diesel vehicles increased 1.88, 1.92, and 1.59 times due to incomplete combustion. In addition, the EFs of PAHs and OPAHs in gasoline vehicles were lower than those in diesel vehicles. In contrast, the proportion of PAHs with highly toxic components, such as dibenzo[a,h]anthracene (DahA) and benzo[a]pyrene (BaP), and the EFs of gas-phase NPAHs in gasoline vehicles were higher than those in diesel vehicles. Furthermore, the emissions of 1,8-DNP from diesel vehicles cannot be disregarded. 1,8-DNP was the main gas-phase NPAHs emitted by China VI and China V diesel vehicles, accounting for 49.3 % and 26.0 %, respectively. Moreover, gas-phase PACs contributed more to the EFs than particle-phase PACs, whereas particle-phase PACs have greater toxic effects. Although the EFs of PAHs are more than 100 times those of NPAHs, the toxic equivalent concentrations (TEQBaP) of PAHs in diesel and gasoline vehicles were approximately 6.5 times and 35 times those of NPAHs. The spatial distribution characteristics revealed that PACs emissions were mainly concentrated in urban areas and highways, and the differences in the toxicity of PACs emissions between different cities depended on the proportion of diesel vehicles. The average TEQBaP of PAHs and NPAHs in Haidong, Haibei, Huangnan, Hainan, Guoluo, and Yushu was 8.42 µg/m3 and 0.36 µg/m3, respectively, while those of Xining and Haixi were 0.24-0.29 µg/m3 and 0.09-0.108 µg/m3 higher, respectively. This study provides a comprehensive understanding of the emission characteristics, health risks, and spatial distribution of PACs from diesel and gasoline vehicle PACs in urban areas.


Assuntos
Poluentes Atmosféricos , Monitoramento Ambiental , Gasolina , Hidrocarbonetos Policíclicos Aromáticos , Emissões de Veículos , Emissões de Veículos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Atmosféricos/análise , Gasolina/análise , China , Medição de Risco , Humanos
6.
Environ Monit Assess ; 196(6): 591, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38819539

RESUMO

The increasing number of vehicles are emitting a large amount of particles into the atmosphere, causing serious harm to the ecological environment and human health. This study conducted the Worldwide Harmonized Light Vehicles Test Cycle (WLTC) to investigate the emission characteristics of particle number (PN) of China-VI gasoline vehicles with different gasoline. The gasoline with lower aromatic hydrocarbons and olefins reduced particulate matter (PM) and PN emissions by 24% and 52% respectively. The average PN emission rate of the four vehicles during the first 300 s (the cold start period) was 7.2 times that of the 300 s-1800s. Additionally, because the particle transmission time and instrument response time, the test results of instantaneous emissions of PN were not synchronized with vehicle specific power (VSP). By calculating the Spearman correlation coefficient between pre-average vehicle specific power (PAVSP) and the test results of PN instantaneous emissions, the delay time was determined as 10s. After the PN emissions results were corrected, the PN emissions were found to be more related to VSP. By analyzing the influence of driving status on emission, this study found that vehicles in acceleration mode increased PN emissions by 76% compared to those in constant speed mode.


Assuntos
Poluentes Atmosféricos , Monitoramento Ambiental , Gasolina , Material Particulado , Emissões de Veículos , Emissões de Veículos/análise , Gasolina/análise , China , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Material Particulado/análise , Condução de Veículo , Poluição do Ar/estatística & dados numéricos
7.
Environ Sci Pollut Res Int ; 31(21): 30454-30466, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38607489

RESUMO

The increase in the number of motor vehicles has intensified the impact of traffic sources on air quality. Our aim was to illustrate the characteristics of PM2.5 emissions from vehicles fueled with E10 (a blend of 10% ethanol and 90% gasoline). A 21-day PM2.5 sampling in a fully enclosed urban tunnel and the component analysis were completed, and the characteristics, sources, and health risks of tunnel PM2.5 were studied. Moreover, the PM2.5 pH and its sensitivity were investigated by the thermodynamic model (ISORROPIA-II). In addition, exposure models were used to assess the health risks of different heavy metals in PM2.5 to humans through respiratory pathways. The two-point Cu/Sb ratio (entrance: 4.0 ± 1.4; exit: 4.4 ± 1.7) was close to the diagnostic criteria indicating a significant impact from brake wear. NO3-, NH4+, and SO42- constituted the main components of water-soluble ions in PM2.5 of the tunnel, accounting for 83.0-84.6% of the total concentration of inorganic ions. The organic carbon/elemental carbon ratio of the tunnel was greater than 2, indicating that the contribution of gasoline vehicle exhaust was significant. The average emission factors of PM2.5 in the fleet was 31.4 ± 16.6 mg/(veh·km). The pH value of PM2.5 in a tunnel environment (4.6 ± 0.3) was more acidic than that in an urban environment (4.9 ± 0.6). The main sensitive factors of PM2.5 pH in the urban atmosphere and tunnel environment were total ammonia (sum of gas and aerosol, NH3) and temperature, respectively. The results of the health risk assessment showed that Pb posed a potential carcinogenic risk, while As and Cd presented unacceptable risks for tunnel workers. The non-carcinogenic risk index of heavy metals of PM2.5 in the tunnel environment exceeded the safety threshold.


Assuntos
Poluentes Atmosféricos , Monitoramento Ambiental , Material Particulado , Emissões de Veículos , Material Particulado/análise , Poluentes Atmosféricos/análise , Emissões de Veículos/análise , Poluição do Ar , Humanos , Gasolina , Medição de Risco
8.
Toxicol Ind Health ; 40(6): 323-336, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38597120

RESUMO

The present study evaluated the protective effect of ascorbic acid (ASCB) against gasoline fumes (PET) induced testicular oxidative stress, sperm toxicity, and testosterone imbalance in Wistar rats. Twenty-four (24) male albino rats (75 ± 16 g) were randomized into three experimental groups (N = 8). The control group: received normal saline, PET group: exposed to PET 6 h daily by inhalation in an exposure chamber and PET + 200 mg ASCB/kg body weight group: exposed to PET 6 h daily by inhalation and administered ASCB per os. Treatment of ASCB and PET exposure was done thrice and five times weekly for a period of 10 weeks respectively. ASCB co-treatment prevented PET-induced increases in the oxidative stress markers (glutathione, glutathione S-transferase, superoxide dismutase, catalase, hydrogen peroxide generation, nitric oxide, and lipid peroxidation) and serum testosterone concentration (p < .05). Sperm quality was low and those with damaged heads and tails increased alongside histological injuries in the PET-exposed rats, which were also minimized with ASCB administration. ASCB protected against PET-induced oxidative stress, sperm, and testis damage in rats.


Assuntos
Ácido Ascórbico , Gasolina , Estresse Oxidativo , Ratos Wistar , Espermatozoides , Testículo , Testosterona , Animais , Masculino , Gasolina/toxicidade , Testosterona/sangue , Estresse Oxidativo/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Ácido Ascórbico/farmacologia , Testículo/efeitos dos fármacos , Ratos , Antioxidantes/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos
9.
Toxicol Ind Health ; 40(6): 337-351, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38597775

RESUMO

Gasoline station attendants are exposed to numerous chemicals that might have genotoxic and carcinogenic potential, such as benzene in fuel vapor and particulate matter and polycyclic aromatic hydrocarbons in vehicle exhaust emission. According to IARC, benzene and diesel particulates are Group 1 human carcinogens, and gasoline has been classified as Group 2A "possibly carcinogenic to humans." At gas stations, self-service is not implemented in Turkey; fuel-filling service is provided entirely by employees, and therefore they are exposed to those chemicals in the workplace during all working hours. Genetic monitoring of workers with occupational exposure to possible genotoxic agents allows early detection of cancer. We aimed to investigate the genotoxic damage due to exposures in gasoline station attendants in Turkey. Genotoxicity was evaluated by the Comet, chromosomal aberration, and cytokinesis-block micronucleus assays in peripheral blood lymphocytes. Gasoline station attendants (n = 53) had higher tail length, tail intensity, and tail moment values than controls (n = 61). In gasoline station attendants (n = 46), the frequencies of chromatid gaps, chromosome gaps, and total aberrations were higher compared with controls (n = 59). Increased frequencies of micronuclei and nucleoplasmic bridges were determined in gasoline station attendants (n = 47) compared with controls (n = 40). Factors such as age, duration of working, and smoking did not have any significant impact on genotoxic endpoints. Only exposure increased genotoxic damage in gasoline station attendants independently from demographic and clinical characteristics. Occupational exposure-related genotoxicity risk may increase in gasoline station attendants who are chronically exposed to gasoline and various chemicals in vehicle exhaust emissions.


Assuntos
Aberrações Cromossômicas , Dano ao DNA , Gasolina , Testes para Micronúcleos , Exposição Ocupacional , Humanos , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Gasolina/toxicidade , Adulto , Masculino , Turquia , Aberrações Cromossômicas/induzido quimicamente , Dano ao DNA/efeitos dos fármacos , Pessoa de Meia-Idade , Poluentes Ocupacionais do Ar/análise , Poluentes Ocupacionais do Ar/toxicidade , Ensaio Cometa , Biomarcadores , Emissões de Veículos/toxicidade , Emissões de Veículos/análise , Linfócitos/efeitos dos fármacos , Feminino , Mutagênicos/toxicidade , Benzeno/toxicidade , Benzeno/análise
11.
Cell Mol Biol (Noisy-le-grand) ; 70(4): 113-117, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38678616

RESUMO

Burn as physical injury ranks as the fourth most prevalent trauma across the world. In this study, we aimed to compare the impact of gasoline burn and chromic acid burn on the internal organs and immune functions in rats. The results showed that the levels of methemoglobin (MHb) to total hemoglobin (Hb) as well as the Cr6+ content showed significant elevation in the chromic acid burn group relative to the gasoline burn group. HE staining was used to evaluate the histological changes in the injured tissues as well as the tissues excised from internal organs. We found that chromic acid burn-induced more severe damage to rat tissues. Gasoline burn showed no significant impact on the intestinal tissues of rats, while the chromic acid burn-induced increased cell death in rat intestines. Moreover, the results of HE staining also revealed that gasoline burn and chromic acid burn showed no evident impact on rat hearts. Gasoline burn also showed no significant effects on the liver, lungs and kidneys of rats, while the chromic acid burn caused injuries to such internal organs in comparison with the control and gasoline burn groups. In addition, the MPO activity was higher in the liver, intestine, lungs and kidneys of rats with chromic acid burn. Furthermore, the expression of inflammation response cytokines was examined in the serum of rats. The results demonstrated that the levels of IL-6, IL-1ß and TNF-α showed a significant increase in both the gasoline burn and chromic acid burn groups of rats relative to the control, and the levels were higher in the chromic acid burn group in comparison with the gasoline burn group. In conclusion, the chromic acid burn-induced more severe organ injury, inflammation and immune response compared with the gasoline burn, which may provide reference data for the clinical treatment of patients with different burn injuries.


Assuntos
Gasolina , Animais , Masculino , Ratos , Fígado/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Pulmão/patologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/imunologia , Ratos Sprague-Dawley , Rim/patologia , Rim/efeitos dos fármacos , Rim/metabolismo , Citocinas/metabolismo , Citocinas/sangue , Queimaduras Químicas/patologia , Queimaduras Químicas/metabolismo , Queimaduras Químicas/imunologia , Peroxidase/metabolismo , Inflamação/patologia
12.
J Contam Hydrol ; 263: 104342, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38643702

RESUMO

A recent diesel spill (dated January 2019 ± 1 month) in a refilling station is investigated by the Radon deficit technique. The primary focus was on quantifying the LNAPL pore saturation as a function of duration of ageing, and on proposing a predictive model for on-site natural attenuation. A biennial monitoring of the local fluctuating shallow aquifer has involved the saturated zone nine times, and the vadose zone only once. Rn background generally measured in external and upstream wells is elaborated further due to the site characteristics, using drilling logs and phreatic oscillations. Notably, this study marks the first application of the Rn deficit method to produce a detailed Rn background mapping throughout the soil depth. Simultaneously, tests are performed on LNAPL surnatant samples to study diesel ageing. In particular, they are focused on temporal variations of LNAPL viscosity (from an initial 3.90 cP to 8.99 cP, measured at 25 °C, after 34 months), and Rn partition coefficient between the pollutant and water (from 47.7 to 80.2, measured at 25 °C, after 14 months). Rn diffusion is also measured in different fluids (0.092 cm2 s-1, 1.14 × 10-5 cm2 s-1, and 2.53 × 10-6 cm2 s-1 at 25 °C for air, water and LNAPL, respectively) directly. All parameters and equations utilized during this study are introduced, discussing their influence on Radon deficit technique from a theoretical point of view. Experimental findings are used to mitigate the effect of LNAPL ageing and of phreatic oscillations on determination of LNAPL saturation index (S.I.LNAPL). Finally, S.I.LNAPL dataset is discussed and elaborated to show the pollutant attenuation across subsurface over time, induced by natural processes primarily. The proposed predictive model for on-site natural attenuation suggests a half-removal time of one year and six months. The significance of such models lies in their capability to assess site-specific reactions to pollutants, thereby enhancing the effectiveness of remediation efforts over time. These experimental findings may offer a novel approach to application of Rn deficit technique and to environmental remediation of persistent organic compounds.


Assuntos
Água Subterrânea , Radônio , Água Subterrânea/química , Radônio/análise , Poluentes Radioativos da Água/análise , Vazamento de Resíduos Químicos , Gasolina , Monitoramento Ambiental/métodos
13.
Environ Sci Pollut Res Int ; 31(22): 32449-32463, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38652187

RESUMO

This article presents the outcomes of a research study focused on optimizing the performance of soybean biofuel blends derived from soybean seeds specifically for urban medium-duty commercial vehicles. The study took into consideration elements such as production capacity, economics and assumed engine characteristics. For the purpose of predicting performance, combustion and emission characteristics, an artificial intelligence approach that has been trained using experimental data is used. At full load, the brake thermal efficiency (BTE) dropped as engine speed increased for biofuel and diesel fuel mixes, but brake-specific fuel consumption (BSFC) increased. The BSFC increased by 11.9% when diesel compared to using biofuel with diesel blends. The mixes cut both maximum cylinder pressure and NO x emissions. The biofuel-diesel fuel proved more successful, with maximum reduction of 9.8% and 22.2 at rpm, respectively. The biofuel and diesel blend significantly improved carbon dioxide ( CO 2 ) and smoke emissions. The biofuel blends offer significant advantages by decreeing exhaust pollutants and enhancing engine performance.


Assuntos
Inteligência Artificial , Biocombustíveis , Glycine max , Emissões de Veículos , Emissões de Veículos/análise , Índia , Gasolina
14.
Environ Sci Pollut Res Int ; 31(23): 33663-33684, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38687451

RESUMO

The use of biofuels has grown in the last decades as a consequence of the direct environmental impacts of fossil fuel use. Elucidating structure, diversity, species interactions, and assembly mechanisms of microbiomes is crucial for understanding the influence of environmental disturbances. However, little is known about how contamination with biofuel/petrofuel blends alters the soil microbiome. Here, we studied the dynamics in the soil microbiome structure and composition of four field areas under long-term contamination with biofuel/fossil fuel blends (ethanol 10% and gasoline 90%-E10; ethanol 25% and gasoline 75%-E25; soybean biodiesel 20% and diesel 80%-B20) submitted to different bioremediation treatments along a temporal gradient. Soil microbiomes from biodiesel-polluted areas exhibited higher richness and diversity index values and more complex microbial communities than ethanol-polluted areas. Additionally, monitored natural attenuation B20-polluted areas were less affected by perturbations caused by bioremediation treatments. As a consequence, once biostimulation was applied, the degradation was slower compared with areas previously actively treated. In soils with low diversity and richness, the impact of bioremediation treatments on the microbiomes was greater, and as a result, the hydrocarbon degradation extent was higher. The network analysis showed that all abundant keystone taxa corresponded to well-known degraders, suggesting that the abundant species are core targets for biostimulation in soil remediation processes. Altogether, these findings showed that the knowledge gained through the study of microbiomes in contaminated areas may help design and conduct optimized bioremediation approaches, paving the way for future rationalized and efficient pollutant mitigation strategies.


Assuntos
Biodegradação Ambiental , Biocombustíveis , Microbiota , Microbiologia do Solo , Solo , Solo/química , Poluentes do Solo/metabolismo , Gasolina
15.
Environ Int ; 187: 108682, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38669721

RESUMO

Concentrations of particulate matter (PM10, PM2.5), ultrafine (UFP), particle number (PNC), black carbon (BC), nitrogen dioxide (NO2) and nitrogen oxides (NOX) were measured in train carriages on diesel and bi-mode trains on inter-city and long-distance journeys in the United Kingdom (UK) using a high-quality mobile measurement system. Air quality on 15 different routes was measured using highly-time resolved data on a total of 119 journeys during three campaigns in winter 2020 and summer 2021; this included 13 different train classes. Each journey was sampled 4-10 times with approximatively 11,000 min of in-train concentrations in total. Mean-journey concentrations were 7.552 µg m-3 (PM10); 3.936 µg m-3 (PM2.5); 333-11,300 # cm-3 (PNC); 225-9,131 # cm-3 (UFP); 0.6-11 µg m-3 (BC); 28-201 µg m-3 (NO2); and 130-3,456 µg m-3 (NOX). The impact of different factors on in-train concentrations was evaluated. The presence of tunnels was the factor with the largest impact on the in-train particle concentrations with enhancements by a factor of 40 greater than baseline for BC, and a factor 6 to 7 for PM and PNC. The engine fuel mode was the factor with the largest impact on NO2 with enhancements of up to 14-times larger when the train run on diesel compared to the times running on electric on hybrid trains. Train classes with an age < 10 years observed the lowest in-train PM, BC and NOX concentrations reflecting improvements in aspects of rail technology in recent years. Air quality on UK diesel trains is higher than ambient concentrations but has lower PM2.5 and PNC than most other transport modes, including subway systems, diesel and petrol cars. This paper adds significantly to the evidence on exposure to poor air quality in transport micro-environments and provides the industry and regulatory bodies with reference-grade measurements on which to establish in-train air quality guidelines.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Monitoramento Ambiental , Material Particulado , Emissões de Veículos , Reino Unido , Poluentes Atmosféricos/análise , Material Particulado/análise , Emissões de Veículos/análise , Poluição do Ar/estatística & dados numéricos , Poluição do Ar/análise , Monitoramento Ambiental/métodos , Ferrovias , Óxidos de Nitrogênio/análise , Dióxido de Nitrogênio/análise , Gasolina/análise
16.
Chemosphere ; 356: 141917, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38588900

RESUMO

Currently, nanobubbles are widely discussed in environmental research due to their unique properties, including significant specific surface area, transfer efficiency, and free radical generation. In this study, O2 and O3 nanobubbles (diameters ranging from 0 to 500 nm) were combined with conventional surfactant technology to investigate their enhanced efficacy in removing diesel contaminants from soil. The impact of various factors such as surfactant concentration, temperature, and soil aging duration on pollutant removal rates was examined across different experimental approaches (stirring/flushing). Soil samples subjected to different treatments were characterized using TG-DTG and FTIR analysis, while GC/MS was employed to assess the degradation products of diesel constituents in the soil. The results indicated that the elution efficiencies of the three surfactants (SDS, SDBS, and TX-100) for diesel in soil correlated positively with concentration (0.3-1.4 CMC) and temperature (18-60 °C), and inversely with aging time (10-300 days), with the elution capacity was SDS > SDBS > TX-100. Mechanical stirring (500 rpm) and temperature variations (18-60 °C) did not affect the stability of the nanobubbles. Upon the introduction of O3 nanobubbles to the surfactant solution, there was a consistent increase in both the removal (degraded and removed) efficiency and rate of diesel under varying experimental conditions, resulting in an enhancement of removal rates by approximately 8-15%. FTIR spectroscopy showed that surfactants containing O3 nanobubbles mitigated the impact on the primary functional groups of soil organic matter. GC/MS analyses indicated that residual pollutants were predominantly alkanes, with degradation difficulty ranking as: alkanes < alkenes < cycloalkanes < aromatic compounds. TG-DTG coupled with GC/MS analysis demonstrated that O3 nanobubbles contributed to a reduction in surfactant residues. This study significantly advances our understanding of how nanobubbles facilitate and optimize surfactant-assisted remediation of contaminated soil, thereby advancing the precise application of nanobubble technology in soil remediation.


Assuntos
Recuperação e Remediação Ambiental , Gasolina , Ozônio , Poluentes do Solo , Solo , Tensoativos , Poluentes do Solo/análise , Poluentes do Solo/química , Recuperação e Remediação Ambiental/métodos , Tensoativos/química , Solo/química , Ozônio/química , Temperatura
17.
Environ Pollut ; 348: 123869, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38548150

RESUMO

The Chinese central government has initiated pilot projects to promote the adoption of gasoline containing 10%v ethanol (E10). Vehicle emissions using ethanol blended fuels require investigation to estimate the environmental impacts of the initiative. Five fuel formulations were created using two blending methods (splash blending and match blending) to evaluate the impacts of formulations on speciated volatile organic compounds (VOCs) from exhaust emissions. Seven in-use vehicles covering China 4 to China 6 emission standards were recruited. Vehicle tests were conducted using the Worldwide Harmonized Test Cycle (WLTC) in a temperature-controlled chamber at 23 °C and -7 °C. Splash blended E10 fuels led to significant reductions in VOC emissions by 12%-75%. E10 fuels had a better performance of reducing VOC emissions in older model vehicles than in newer model vehicles. These results suggested that E10 fuel could be an option to mitigate the VOC emissions. Although replacing methyl tert-butyl ether (MTBE) with ethanol in regular gasoline had no significant effects on VOC emissions, the replacement led to lower aromatic emissions by 40%-60%. Alkanes and aromatics dominated approximately 90% of VOC emissions for all vehicle-fuel combinations. Cold temperature increased VOC emissions significantly, by 3-26 folds for all vehicle/fuel combinations at -7 °C. Aromatic emissions were increased by cold temperature, from 2 to 26 mg/km at 23 °C to 33-238 mg/km at -7 °C. OVOC emissions were not significantly affected by E10 fuel or cold temperature. The ozone formation potential (OFP) and secondary organic aerosol formation potential (SOAFP) of splash blended E10 fuels decreased by up to 76% and 81%, respectively, compared with those of E0 fuels. The results are useful to update VOC emission profiles of Chinese vehicles using ethanol blended gasoline and under low-temperature conditions.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Gasolina/análise , Temperatura Baixa , Compostos Orgânicos Voláteis/análise , Etanol , Emissões de Veículos/análise , China , Poluentes Atmosféricos/análise
18.
Sci Rep ; 14(1): 5080, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429521

RESUMO

The polycyclic aromatic hydrocarbon (PAH) concentrations in total suspended particulate matter (TSP) samples collected from October, 2021 to September, 2022 were analyzed to clarify the pollution characteristics and sources of 16 PAHs in the atmospheric TSP in Bengbu City. The ρ(PAHs) concentrations ranged from 1.71 to 43.85 ng/m3 and higher concentrations were detected in winter, followed by spring, autumn, and summer. The positive matrix factorization analysis revealed that, in spring and summer, PAH pollution was caused mainly by industrial emissions, gasoline and diesel fuel combustion, whereas in autumn and winter, it was coal, biomass and natural gas combustion. The cluster and potential source factor analyses showed that long-range transport was a significant factor. During spring, autumn, and winter, the northern and northwestern regions had a significant impact, whereas the coastal area south of Bengbu had the greatest influence in summer. The health risk assessment revealed that the annual total carcinogenic equivalent concentration values for PAHs varied from 0.0159 to 7.437 ng/m3, which was classified as moderate. Furthermore, the annual incremental lifetime cancer risk values ranged from 1.431 × 10-4 to 3.671 × 10-3 for adults and from 6.823 × 10-5 to 1.749 × 10-3 for children, which were higher than the standard.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Adulto , Criança , Humanos , Material Particulado/análise , Poluentes Atmosféricos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Monitoramento Ambiental , Medição de Risco , Gasolina , China
19.
Environ Pollut ; 347: 123665, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38432344

RESUMO

Vehicular emissions deteriorate air quality in urban areas notably. The aim of this study was to conduct an in-depth characterization of gaseous and particle emissions, and their potential to form secondary aerosol emissions, of the cars meeting the most recent emission Euro 6d standards, and to investigate the impact of fuel as well as engine and aftertreatment technologies on pollutants at warm and cold ambient temperatures. Studied vehicles were a diesel car with a diesel particulate filter (DPF), two gasoline cars (with and without a gasoline particulate filter (GPF)), and a car using compressed natural gas (CNG). The impact of fuel aromatic content was examined for the diesel car and the gasoline car without the GPF. The results showed that the utilization of exhaust particulate filter was important both in diesel and gasoline cars. The gasoline car without the GPF emitted relatively high concentrations of particles compared to the other technologies but the implementation of the GPF decreased particle emissions, and the potential to form secondary aerosols in atmospheric processes. The diesel car equipped with the DPF emitted low particle number concentrations except during the DPF regeneration events. Aromatic-free gasoline and diesel fuel efficiently reduced exhaust particles. Since the renewal of vehicle fleet is a relatively slow process, changing the fuel composition can be seen as a faster way to affect traffic emissions.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Emissões de Veículos/análise , Poluentes Atmosféricos/análise , Gasolina , Poluição do Ar/prevenção & controle , Poluição do Ar/análise , Automóveis , Poeira , Aerossóis , Veículos Automotores , Material Particulado/análise
20.
Int J Legal Med ; 138(4): 1315-1321, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38332349

RESUMO

Herein, we present the case of accidental intravenous injection of gasoline in a 62-year-old male who was admitted to a dialysis center for his regular hemodialysis. Due to previous contact with another SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) positive patient, the hemodialysis was conducted in an isolated room. At the end of the procedure, the nurse, wearing all necessary personal protective equipment (PPE), in the intent to clean the dialysis catheter, applied medical gasoline, instead of 0.9% sodium chloride, intravenously to the patient. Soon afterwards, the patient's clinical condition deteriorated, and cardiopulmonary resuscitation was started. Despite the immediate reaction of the medical staff, after two successful cardiopulmonary reanimation and necessary intensive care measures, the patient suffered respiratory, metabolic, and lactic acidosis, hypotension, and tachyarrhythmia and ultimately died 7 h after the incident. The autopsy was conducted under the order of the district attorney. Main autopsy findings were marked congestion; right pleural and pericardial effusion; brain and lung edema; enlarged heart with left ventricle thickening and mild perivascular fibrosis; nephrosclerosis; tubular thyroidization; and interstitial fibrosis with inflammation. Gasoline presence was indisputably proven by conducted toxicology analysis in lung, bile, and brain samples. Traces of gasoline could be noted in the patient's blood sample in comparison to the blood that did not contain gasoline, but it was not possible to confidently claim that gasoline was present in the blood. Based on relevant findings, we concluded that the death of the patient was violent and that the cause of death was acute intoxication by gasoline.


Assuntos
Gasolina , Diálise Renal , Humanos , Masculino , Pessoa de Meia-Idade , Gasolina/intoxicação , Evolução Fatal , COVID-19 , Injeções Intravenosas , Pulmão/patologia
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