Search

The CuO nanorods were in-situ grown on sensing electrodes by a chemical bath method for the detection of volatile organic compounds (VOCs). The synthesized material was characterized by using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy (FTIR). The CuO nanorods, with lengths of 100–150 nm and diameters of 35–55 nm, were uniformly formed into a thin film on the electrode surface, with a thickness of approximately 1 μm. The gas test results demonstrated that the sensor achieved a peak response of 1.32 for formaldehyde at 200 °C, and a response of 1.92 for ethanol at 175 °C. At a concentration of 50 ppm, ethanol and formaldehyde at an operating temperature of 200 °C exhibit short response/recovery times of 28 s/48 s for ethanol and 45 s/62 s for methanol, respectively, coupled with good reproducibility. Moreover, the sensor exhibited a power-law response to varying gas concentrations and showcased superior selectivity in the VOCs gas detection. This in-situ growing CuO of our work provides a facial gas sensing material fabricated method. [ABSTRACT FROM AUTHOR]

Increased levels and detrimental effects of volatile organic compounds (VOCs) on air quality and human health have become an important issue in the environmental field. Benzene is classified as one of the most hazardous air pollutants among non-halogenated aromatic hydrocarbons with toxic, carcinogenic, and mutagenic effects. Various technologies have been applied to decrease harmful emissions from various sources such as petrochemistry, steel manufacturing, organic chemical, paint, adhesive, and pharmaceutical production, vehicle exhausts, etc. Catalytic oxidation to CO2 and water is an attractive approach to VOC removal due to high efficiency, low energy consumption, and the absence of secondary pollution. However, catalytic oxidation of the benzene molecule is a great challenge because of the extraordinary stability of its six-membered ring structure. Developing highly efficient catalysts is of primary importance for effective elimination of benzene at low temperatures. This review aims to summarize and discuss some recent advances in catalyst composition and preparation strategies. Advantages and disadvantages of using noble metal-based catalysts and transition metal oxide-based catalysts are addressed. Effects of some crucial factors such as catalyst support nature, metal particle size, electronic state of active metal, redox properties, reactivity of lattice oxygen and surface adsorbed oxygen on benzene removal are explored. Thorough elucidation of reaction mechanisms in benzene oxidation is a prerequisite to develop efficient catalysts. Benzene oxidation mechanisms are analyzed based on in situ catalyst characterization, reaction kinetics, and theoretical simulation calculations. Considering the role of oxygen vacancies in improving catalytic performance, attention is given to oxygen defect engineering. Catalyst deactivation due to coexistence of water vapor and other pollutants, e.g., sulfur compounds, is discussed. Future research directions for rational design of catalysts for complete benzene oxidation are provided. [ABSTRACT FROM AUTHOR]

Changes in the work function provide a fingerprint to characterize analyte binding in charge transfer-based sensor devices. Hence, a rational sensor design requires a fundamental understanding of the microscopic factors controlling the modification of the work function. In the current investigation, we address the mechanisms behind the work function change (WFC) for the adsorption of four common volatile organic compounds (toluene, ethanol, 2-Furfurylthiol, and guaiacol) on different nitrogen-doped graphene-based 2D materials using density functional theory. We show that competition between the surface dipole moment change induced by spatial charge redistribution, the one induced by the pure adsorbate, and the one caused by the surface deformation can quantitatively predict the work function change. Furthermore, we also show this competition can explain the non-growing work function change behavior in the increasing concentrations of nitrogen-doped graphenes. Finally, we propose possible design principles for WFC of VOCs interacting with N-doped graphene materials. [ABSTRACT FROM AUTHOR]

In this research, silver was loaded onto ZnO using the photoreduction method to enhance the photocatalytic activity of ZnO in the visible region. The photocatalytic activity of ZnO and Ag/ZnO was investigated for the gas‐phase degradation of volatile organic compounds such as ethyl acetate, ethanol, and toluene under visible light irradiation. The Ag/ZnO effectively decomposed ethyl acetate, toluene, and ethanol separately and in a mixed state. The characteristics of Ag/ZnO and ZnO were studied using XRD, SEM, EDAX, XPS, BET, UV–vis DRS, and PL analyses. The XRD pattern confirmed the formation of metallic silver in the Ag/ZnO photocatalyst. The PL results showed that the loading of Ag on the ZnO significantly reduces the photoelectron‐hole pairs recombination in Ag/ZnO. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the influence of different growing conditions on the amount of leaf pigments (chlorophylls, carotenoids), bioactive metabolites, such as polyphenols, flavonoids, lawsone and volatile organic compounds (VOCs) of Lawsonia inermis L. (henna) plants. Young henna plants were cultivated for two months in a growth chamber (GC) and in open-air conditions during summer under the Mediterranean climate (OF), and leaves were analysed to evaluate their adaptive responses. The different growth conditions modified the carbon allocation priorities, increasing antioxidant metabolites (e.g. phenolic and flavonoid compounds) while decreasing lawsone in GC conditions. Quali-quantitative changes were observed for VOCs. This study revealed that GC conditions permit an alternative use of Lawsonia cultivation, because of the increase in the endogenous content of bioactive secondary metabolites with many potential biological activities. [ABSTRACT FROM AUTHOR]

Introduction: The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has posed extraordinary challenges to global health systems and economies. The virus's rapid evolution has resulted in several variants of concern (VOCs), including the highly transmissible Omicron variant, characterized by extensive mutations. In this study, we investigated the genetic diversity, population differentiation, and evolutionary dynamics of the Omicron VOC during the fifth wave of COVID-19 in Pakistan. Methods: A total of 954 Omicron genomes sequenced during the fifth wave of COVID-19 in Pakistan were analyzed. A Bayesian framework was employed for phylogenetic reconstructions, molecular dating, and population dynamics analysis. Results: Using a population genomics approach, we analyzed Pakistani Omicron samples, revealing low within-population genetic diversity and significant structural variation in the spike (S) protein. Phylogenetic analysis showed that the Omicron variant in Pakistan originated from two distinct lineages, BA.1 and BA.2, which were introduced from South Africa, Thailand, Spain, and Belgium. Omicron-specific mutations, including those in the receptor-binding domain, were identified. The estimated molecular evolutionary rate was 2.562E-3 mutations per site per year (95% HPD interval: 8.8067E-4 to 4.1462E-3). Bayesian skyline plot analysis indicated a significant population expansion at the end of 2021, coinciding with the global Omicron outbreak. Comparative analysis with other VOCs showed Omicron as a highly divergent, monophyletic group, suggesting a unique evolutionary pathway. Conclusions: This study provides a comprehensive overview of Omicron's genetic diversity, genomic epidemiology, and evolutionary dynamics in Pakistan, emphasizing the need for global collaboration in monitoring variants and enhancing pandemic preparedness. [ABSTRACT FROM AUTHOR]

Volatile Organic Compounds (VOCs) are not only essential precursors for the formation of ozone and PM2.5, but also hazardous to human health and responsible for unpleasant odors. The pharmaceutical industry has become an important industrial source of VOCs due to China's large emissions and complex emission chains. In total, 245 VOCs samples were collected and analyzed from 11 typical pharmaceutical companies in Zibo City of the North China Plain, in order to investigate the VOCs emission characteristics and odor impacts. The emission factor for the pharmaceutical industry was 7.97 ± 8.21 g/kg pharmaceuticals, while the main emission links were chimney emissions, equipment sealing leakage, and so on. Finally, considering both purifying efficiency and economic benefits, the multistage absorption (AB) method is most effective for VOCs concentrations below 100 mg/m3, while UV photo-oxygenation combined with adsorption (UVA) is more suitable for concentrations below 300 mg/m3. The Regenerative Thermal Oxidizer (RTO), Catalytic Oxidizer (CO), and Condensation + Adsorption (CA) technologies demonstrated greater stability and efficiency, particularly in the treatment of complex organic pollutants, highlighting their advantages in both VOCs and odor removal at higher concentrations. [ABSTRACT FROM AUTHOR]

Since actual industrial emissions contain a wide range of volatile organic compounds, studies into the simultaneous catalytic degradation of multi-component VOCs are essential. This work developed Pd-CeZrOx samples for the simultaneous elimination of benzene and toluene. Firstly, CeZrOx supports were synthesized using several methods (co-precipitation, CTAB template co-precipitation, and sol–gel method). Pd active species were then added into the 1.0Pd-CeZrOx samples using the impregnation procedure. XRD, BET, NH3-TPD, Raman, EPR, XPS, and H2-TPR were utilized to analyze the as-prepared Pd-CeZrOx samples. The catalytic performance tests reveal that the performance of 1.0Pd-CeZrOx-CTAB outperforms that of 1.0Pd-CeZrOx-PM and 1.0Pd-CeZrOx-CASG, and 1.0Pd-CeZrOx-CTAB displays superior catalytic activity for both benzene and toluene oxidation. The improved redox properties, the abundant surface oxygen vacancies, and the surface Pd2+ species of the 1.0Pd-CeZrOx-CTAB sample may be responsible for the simultaneous degradation activity of benzene and toluene. [ABSTRACT FROM AUTHOR]

This study employed proton transfer reaction mass spectrometry (PTR-MS) and gas chromatography–mass spectrometry (GC-MS) to identify and monitor volatile organic compounds (VOCs) in frying fumes generated during the deep frying of tempeh. The research aimed to assess the impact of frying conditions, including frying temperature, oil type, and repeated use cycles, on the formation of thermal decomposition products. A total of 78 VOCs were identified, with 42 common to both rapeseed and palm oil. An algorithm based on cosine similarity was proposed to group variables, resulting in six distinct emission clusters. The findings highlighted the prominence of saturated and unsaturated aldehydes, underscoring the role of fatty acid oxidation in shaping the frying fume composition. This study not only corroborates previous research but also provides new insights into VOC emissions during deep frying, particularly regarding the specific emission profiles of certain compound groups and the influence of frying conditions on these profiles. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) are common constituents of many consumer products. Although many VOCs are generally considered harmless at low concentrations, some compound classes represent substances of concern in relation to human (inhalation) exposure and can elicit adverse health effects, especially when concentrations build up, such as in indoor settings. Determining VOC emissions from consumer products, such as toys, utensils or decorative articles, is of utmost importance to enable the assessment of inhalation exposure under real-world scenarios with respect to consumer safety. Due to the diverse sizes and shapes of such products, as well as their differing uses, a one-size-fits-all approach for measuring VOC emissions is not possible, thus, sampling procedures must be chosen carefully to best suit the sample under investigation. This review outlines the different sampling approaches for characterizing VOC emissions from consumer products, including headspace and emission test chamber methods. The advantages and disadvantages of each sampling technique are discussed in relation to their time and cost efficiency, as well as their suitability to realistically assess VOC inhalation exposures. [ABSTRACT FROM AUTHOR]

The Permian Basin is the largest petroleum producing region in the United States. Few studies have investigated impact the Petroleum Industry had on the air quality of the Permian Basin. Industry operations in the Basin has two primary impacts on air quality, (a) it significantly contributes carbon dioxide (CO2) and methane (CH4) to the atmosphere during extraction, transport and use of fossil fuels, (b) industry operations influence public health especially when populations are in proximity to all categories of oil and gas facilities. The advent of Covid-19 in late 2019 and a severe drought that began prior to 2019 in West Texas have created unusual circumstances regarding air quality and public health in the Permian Basin. This study has monitored airborne pollen, spores, fungal spores, and other organically derived particles, and inorganic particulate matter (1, 2.5, 10-micron particulate matter (PM) and total suspended particles (TSP)), volatile organic compounds (VOCs), and sulfur dioxide (SO2). The pandemic caused a historic reduction in oil and gas production slowing operations in the Permian Basin to near zero during the study period, reducing environmental effects on air quality and concomitantly an increase in flaring of natural gas. Although there were increases in the release of VOCs fixed base monitors detected no notable increase. However, an increase in the concentration of airborne pollutants (VOCs and SO2) shows a close correlation with proximity to oil and gas facilities and the intensity of industry operations. This phenomenon is attributed to the highly local nature of flaring and CH4 plume emissions from leaking oil and gas facilities. Air quality improved in the Permian Basin due to reduction in production activity because of the Covid-19 pandemic, and the reduction of particulate matter due to the ongoing drought during the study period. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) are ubiquitous in the atmosphere, posing significant adverse impacts on air quality and human health. However, current research on atmospheric VOCs mainly focuses on specific regions or industries, without comprehensive national-level analysis. In this study, a total of 99 articles on atmospheric VOCs in China published from 2015 to 2024 were screened, and data on their concentrations, source apportionment, and health risks were extracted and summarized. The results revealed that the annual average concentrations of TVOCs and their groups in China generally increased and then decreased between 2011 and 2022, peaking in 2018–2019. A distinct seasonal pattern was observed, with the highest concentrations occurring in winter, followed by autumn, spring, and summer. TVOC emissions were highly concentrated in northern and eastern China, mainly contributed by alkanes and alkenes. Source apportionment of VOCs indicated that vehicle sources (32.9% ± 14.3%), industrial emissions (18.0% ± 12.8%), and other combustion sources (13.0% ± 13.0%) were the primary sources of VOCs in China. There was a significant positive correlation (p < 0.05) between the annual mean VOC concentration and population size, and a notable negative correlation (p < 0.05) with GDP per capita. Atmospheric VOCs had no non-carcinogenic risk (HI = 0.5) but exhibited a probable carcinogenic risk (7.5 × 10−5), with relatively high values for 1,2-dibromoethane, 1,2-dichloroethane, and naphthalene. The health risk was predominantly driven by halocarbons. These findings are essential for a better understanding of atmospheric VOCs and for developing more targeted VOC control measures. [ABSTRACT FROM AUTHOR]

Human production and living processes emit excessive VOCs into the atmosphere, posing significant threats to both human health and the environment. The photothermal catalytic oxidation process is an organic combination of photocatalysis and thermocatalysis. Utilizing photothermal catalytic degradation of VOCs can achieve better catalytic activity at lower temperatures, resulting in more rapid and thorough degradation of these compounds. Photothermal catalysis has been increasingly applied in the treatment of atmospheric VOCs due to its many advantages. A brief introduction on the three modes of photothermal catalysis is presented. Depending on the main driving force of the reactions, they can be categorized into thermal‐assisted photocatalysis (TAPC), photo‐assisted thermal catalysis (PATC) and photo‐driven thermal catalysis (PDTC). The commonly used catalyst design methods and reactor types for photothermal catalysis are also briefly introduced. This paper then focuses on recent developments in specific applications for photothermal catalytic oxidation of different types of VOCs and their corresponding principles. Finally, the problems and challenges facing VOC degradation through this method are summarized, along with prospects for future research. [ABSTRACT FROM AUTHOR]

Rajasthan, experiencing rapid industrialization and urbanization, faces critical air quality challenges, particularly concerning toxic volatile organic compounds (VOCs) such as BTEX (Benzene, Toluene, Ethylbenzene, Xylene). This study presents a long-term analysis of BTEX concentrations across various cities in Rajasthan, India, using data from the Central Pollution Control Board (CPCB) from 2017 to 2022. The findings revealed that the average ∑BTEX concentrations increased from 4.15 µg/m3 in 2017 to 12.29 µg/m3 in 2022, with a temporary decline in 2020. The Hazard Quotient (HQ) values for BTEX exposure ranged from 0.052 to 0.15 for males, 0.056 to 0.17 for females, and 0.09 to 0.29 for children over the study period, indicating higher health risks for children. Similarly, the Lifetime Cancer Risk (LCR) values varied from 6.04 × 10⁻⁶ to 1.92 × 10⁻5 for males, 1.09 × 10⁻⁶ to 2.24 × 10⁻5 for females, and 1.17 × 10⁻5 to 3.73 × 10⁻5 for children. The results demonstrate that children are at a greater cancer risk from BTEX exposure compared to adults. This study emphasizes the urgent need for effective air pollution control measures and continuous monitoring to protect public health, particularly vulnerable populations like children. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs), particularly aromatic hydrocarbons, pose significant environmental risks due to their toxicity and role in the formation of secondary pollutants. This study explores the potential of catalytic pyrolysis as an innovative strategy for the effective remediation and conversion of aromatic hydrocarbon pollutants. The research investigates the high-efficiency removal and resource recovery of the VOC toluene using a Ni/Al2O3 catalyst. The Ni/Al2O3 catalyst was synthesized using the impregnation method and thoroughly characterized. Various analytical techniques, including scanning electron microscopy, X-ray diffraction, and N2 adsorption–desorption isotherms, were employed to characterize the Al2O3 support, NiO/Al2O3 precursor, Ni/Al2O3 catalyst, and the resulting solid carbon. Results indicate that Ni predominantly occupies the pores of γ-Al2O3, forming nano/microparticles and creating interstitial pores through aggregation. The catalyst demonstrated high activity in the thermochemical decomposition of toluene into solid carbon materials and COx-Free hydrogen, effectively addressing toluene pollution while recovering valuable resources. Optimal conditions were identified, revealing that a moderate temperature of 700 °C is most favorable for the catalytic process. Under optimized conditions, the Ni/Al2O3 catalyst removed 1328 mg/g of toluene, generated 915 mg/g of carbon material, and produced 1234 mL/g of hydrogen. The prepared carbon material, characterized by its mesoporous structure and high specific surface area graphite nanofibers, holds potential application value in adsorption, catalysis, and energy storage. This study offers a promising approach for the purification and resource recovery of aromatic volatile organic compounds, contributing to the goals of a circular economy and green chemistry. [ABSTRACT FROM AUTHOR]

Crumb rubber-modified asphalt mixtures have been proven to have extensive utilization value in road engineering. However, the rubber releases more fumes during the construction period, which causes severe harm to human health and the environment. This research focused on the emission risk of asphalt fume from crumb rubber-modified asphalt, and then the inhibition technology was also optimized. Firstly, the emission behavior and the hazardous evaluation of the asphalt fume from crumb rubber-modified asphalt were investigated. Then, the characteristics of the inhibition materials were evaluated. Finally, the reduction in the emission of inhibited crumb rubber-modified asphalt fume was identified, and the optimized formula was determined based on the inhibition effect, rheological properties, and cost. The results indicate that crumb rubber-modified asphalts release more fume components with an increment in the temperature and crumb rubber content. Desulfurized rubber reduces the release of H2S and NO. Benzene compounds, including paraxylene, toluene, and benzene, are the most released pollutants that harm human health, especially DS CRA 20% and CRA 50%. Kaolin powder and expanded graphite have a sufficient pore structure and volume, the addition of which reduces the release of pollutants while possibly promoting the release of NO and H2S. Their addition also has a significant control effect on the release of particulate matter at 170 °C and 185 °C. With the consideration of emissions, rheological properties, and cost, CRA 40%-EG2%-KL2% was determined as the optimization formula. This research is helpful to the application of crumb rubber-modified asphalt in road construction and maintenance. [ABSTRACT FROM AUTHOR]

AbstractInvestigating the biotechnological potential of wild microorganisms is paramount for optimizing bioprocesses. Given this premise, we looked for yeasts in Brazilian native stingless bees, considering the recognized potential of pollinating insect-associated microorganisms for the production of volatile organic compounds (VOCs). Two yeast strains of the species Meyerozyma caribbica were isolated from bees Scaptotrigona postica and evaluated for their fermentative capacity. Both yeasts were capable of fermenting sucrose (the main sugar used in the Brazilian ethanol industry) with over 90% efficiency and yields of up to 0.504 g/g. Through an experimental design analysis (CCD), it was verified that the ethanol productivity of these yeasts can also benefit from high concentrations of sucrose and low pH values, desirable traits for microorganisms in this biofuel production. At the same time, CCD analyses also showed the great capacity of these M. caribbica strains to produce another alcohol of broad biotechnological interest, 2-phenylethanol. Interestingly, the statistical analyses demonstrated that greater production of this compound can occur at high sugar concentrations and low availability of nitrogen sources, which can be easily achieved using residual low-cost feedstocks. Thus, our results suggest that these M. caribbica strains may be efficiently used in both ethanol and 2-phenylethanol production. [ABSTRACT FROM AUTHOR]

This work presents a year-long integral study of air quality parameters in Ciudad Real, a small city in the center of Spain, and its influence on the nearby national park, Las Tablas de Daimiel. The study covers meteorological parameters and criteria pollutants such as O3, NO, NO2, SO2, and PM10. Additionally, for each month, a 1-week campaign was performed sampling air in sorbent tubes with 8-h time resolution to analyze anthropogenic volatile organic compounds and the effects of seasons, daytime, and working-weekend days. During these campaigns, 24-h PM2.5 samples were also collected to measure the load of bacteria and fungi, as well as the trace concentrations of elements. The city and the national park NOx profiles showed that emissions from the town had a non-perceivable effect on the protected area. PM10 levels in Ciudad Real were influenced by Saharan intrusions, as was the national park; however, Ciudad Real had a higher contribution from anthropogenic sources. Ozone levels were lower in the city during the cold season due to the higher concentration of NOx and have not changed significantly in the last decade. The VOCs with higher average concentrations were toluene, m,p-xylene, benzene, methylene chloride, and o-xylene, with traffic being the main source of these pollutants in the city. For benzene and carbon tetrachloride levels, weak carcinogenic risks were estimated. In PM2.5, the most abundant metals were Na, Zn, Mg, Ca, Al, Fe, and K. The carcinogenic and non-carcinogenic risks estimated from the levels of the studied metals were negligible. Bacterial and fungal counts positively correlated with the concentration of PM2.5. Microbial community composition showed seasonal variability, with the dominance of human pathogenic bacteria which correlated with certain pollutants such as SO2. Bacillus and Cutibacterium were the most abundant genera. [ABSTRACT FROM AUTHOR]

In this study, we investigate the adsorption and sensing capabilities of pristine (MoSi2N4) and nitrogen‐vacancy induced (MoSi2N4−VN) monolayers towards five potential lung cancer volatile organic compounds (VOCs), such as 2,3,4‐trimethylhexane (C9H20), 4‐methyloctane (C9H20), o‐toluidine (C7H9N), Aniline (C6H7N), and Ethylbenzene (C8H10). Spin‐polarized density functional theory (DFT) calculations reveal that MoSi2N4 weakly adsorb the mentioned VOCs, whereas the introduction of nitrogen vacancies significantly enhances the adsorption energies ( Eads ${{E}_{ads}}$ ), both in gas phase and aqueous medium. The MoSi2N4−VN monolayers exhibit a reduced bandgap and facilitate charge transfer upon VOCs adsorption, resulting in enhanced Eads ${{E}_{ads}}$ values of −0.83, −0.76, −0.49, −0.61, and −0.50 eV for 2,3,4‐trimethylhexane, 4‐methyloctane, o‐toluidine, Aniline, and Ethylbenzene, respectively. Bader charge analysis and spin‐polarized density of states (SPDOS) elucidate the charge redistribution and hybridization between MoSi2N4−VN and the adsorbed VOCs. The work function of MoSi2N4−VN is significantly reduced upon VOCs adsorption due to induced dipole moments, enabling smooth charge transfer and selective VOCs sensing. Notably, MoSi2N4−VN monolayers exhibit sensor responses ranging from 16.2 % to 26.6 % towards the VOCs, with discernible selectivity. Importantly, the recovery times of the VOCs desorption is minimal, reinforcing the suitability of MoSi2N4−VN as a rapid, and reusable biosensor platform for efficient detection of lung cancer biomarkers. Thermodynamic analysis based on Langmuir adsorption model shows improved adsorption and detection capabilities MoSi2N4−VN under diverse operating conditions of temperatures and pressures. [ABSTRACT FROM AUTHOR]

Premise: Plants produce an array of floral olfactory and visual cues to attract pollinators, including volatile organic compounds (VOC), which mediate plant–pollinator interactions and may be influenced by herbivory and neighboring plants. Consequently, these factors may affect plant fitness by disrupting pollination. However, most evidence comes from controlled experiments, limiting our understanding of how VOCs function in natural populations. This study investigated how herbivory and conspecific ramet density influence floral VOC profile, pollination, and seed production in a naturally occurring population of Solidago altissima. Methods: We recorded leaf herbivory and ramet density surrounding one focal ramet in 1‐m2 plots. We collected VOCs from the floral headspace and measured ovary fertilization as a proxy for pollination success and the number of seeds produced by the focal ramet. Results: Our findings revealed interactive effects between ramet density and herbivory on floral VOC emission, richness, and diversity. Specifically, at lower ramet densities, herbivory did not affect floral volatile emissions. However, in highly dense stands, herbivory suppressed floral volatile emissions. Despite these changes, floral volatiles did not affect pollination and the number of seeds in S. altissima. Conclusions: Our field‐based findings underscore the importance of understanding the complex responses of floral VOCs to environmental stressors and their contributions to plant reproduction within natural communities. Our results suggest that while herbivory and ramet density influence floral scent, these changes do not affect reproduction in our study. Ultimately, generalist‐pollinated plants like S. altissima might not rely heavily on chemical signaling during pollination. [ABSTRACT FROM AUTHOR]

Recently, volatile organic compound (VOC) determination in exhaled breath has seen growing interest due to its promising potential in early diagnosis of several pathological conditions, including chronic kidney disease (CKD). Therefore, this study aimed to identify the breath VOC pattern providing an accurate, reproducible and fast CKD diagnosis at early stages of disease. A cross-sectional observational study was carried out, enrolling a total of 30 subjects matched for age and gender. More specifically, the breath samples were collected from (a) 10 patients with end-stage kidney disease (ESKD) before undergoing hemodialysis treatment (DIAL); (b) 10 patients with mild-moderate CKD (G) including 3 patients in stage G2 with mild albuminuria, and 7 patients in stage G3 and (c) 10 healthy controls (CTRL). For each volunteer, an end-tidal exhaled breath sample and an ambient air sample (AA) were collected at the same time on two sorbent tubes by an automated sampling system and analyzed by Thermal Desorption–Gas Chromatography–Mass Spectrometry. A total of 110 VOCs were detected in breath samples but only 42 showed significatively different levels with respect to AA. Nonparametric tests, such as Wilcoxon/Kruskal–Wallis tests, allowed us to identify the most weighting variables able to discriminate between AA, DIAL, G and CTRL breath samples. A promising multivariate data mining approach incorporating only selected variables (showing p-values lower than 0.05), such as nonanal, pentane, acetophenone, pentanone, undecane, butanedione, ethyl hexanol and benzene, was developed and cross-validated, providing a prediction accuracy equal to 87% and 100% in identifying patients with both mild–moderate CKD (G) and ESKD (DIAL), respectively. [ABSTRACT FROM AUTHOR]

Kidney diseases are a group of conditions related to the functioning of kidneys, which are in turn unable to properly filter waste and excessive fluids from the blood, resulting in the presence of dangerous levels of electrolytes, fluids, and waste substances in the human body, possibly leading to significant health effects. At the same time, the toxins amassing in the organism can lead to significant changes in breath composition, resulting in halitosis with peculiar features like the popular ammonia breath. Starting from this evidence, scientists have started to work on systems that can detect the presence of kidney diseases using a minimally invasive approach, minimizing the burden to the individuals, albeit providing clinicians with useful information about the disease's presence or its main related features. The electronic nose (e-nose) is one of such tools, and its applications in this specific domain represent the core of the present review, performed on articles published in the last 20 years on humans to stay updated with the latest technological advancements, and conducted under the PRISMA guidelines. This review focuses not only on the chemical and physical principles of detection of such compounds (mainly ammonia), but also on the most popular data processing approaches adopted by the research community (mainly those relying on Machine Learning), to draw exhaustive conclusions about the state of the art and to figure out possible cues for future developments in the field. [ABSTRACT FROM AUTHOR]

Understanding the pollution levels, potential sources, and chemical reactivity of atmospheric volatile organic compounds (VOCs), the key precursors of ozone (O3) and fine particulate matter (PM2.5), is important for emission control and air pollution abatement. This study presents a systematic VOCs analysis in a less studied heavy industrial urban agglomeration located in Northeast China. Using a cruising platform, we conducted real-time monitoring of VOC concentrations and components at Changchun (CC), Jilin (JL), Siping (SP), and Liaoyuan (LY) in Jilin Province. During the observation period, the average VOC concentrations at CC, JL, SP, and LY were 63.38 ± 127.03, 260.39 ± 855.76, 18.06 ± 17.17, and 10.12 ± 17.48 µg/m3, respectively. Halocarbons were predominant with a high percentage of contribution (22.4–31.1%) to the total observed VOCs for all cities. Combined with 2020-based anthropogenic VOCs emission inventory of Jilin Province, we concluded that industrial processes had the largest contribution to VOCs concentration in CC, whereas petrochemical emission was the major source of VOCs in JL. The assessment of atmospheric photochemical reactivity indicates the dominant role of aromatics and alkenes in O3 formation potential (OFP). As the second-most abundant species in CC and JL, aromatics contributed over 50% of the OFPs. Alkenes played a dominant role in O3 formation in SP and LY, accounting for nearly half of the total OFPs. Considering the VOC emission characteristics and OFP results, we suggest that reducing aromatics emissions, particularly benzene, toluene, ethylbenzene, and xylene, should be given higher priority to mitigate O3 pollution and prevent health risks. Moreover, industrial-related, and petrochemical sources are crucial in the evolution of O3 pollution, which should be incorporated into heavy industrial urban air quality management and targeted control of O3 pollution in Northeast China. [ABSTRACT FROM AUTHOR]

Plasma from electric discharges can be used in the abatement of volatile organic compounds (VOCs). The application of gas-phase pulsed corona discharge (PCD) in air–water mixtures provides favorable conditions for the oxidation of VOCs at unsurpassed energy efficiency. This research investigates the impact of water sprinkling on PCD performance in the oxidation of m-xylene as a model compound. Experimental research into the plasma treatment of continuous air flow was undertaken using the PCD reactor in dry and water-sprinkled modes. Water sprinkling more than doubled the m-xylene oxidation rate, which can be attributed to abundant OH-radicals produced at the plasma–water interface. Water sprinkling substantially reduced the formation of nitrous oxide, which is considered to be a secondary pollutant in the outlet air. Ozone is considered a by-product helping the subsequent photocatalytic oxidation of potential residues and photocatalyst maintenance. The use of water-sprinkled PCD is a promising approach to energy-efficient abatement of VOCs. [ABSTRACT FROM AUTHOR]

This study investigates the effects of breeds, feeding methods, and parts on the volatile flavor of yak meat. Gas chromatography–ion mobility spectrometry (GC-IMS) and multivariate analysis were used to analyze the volatile organic components (VOCs) in yak meat from various sources. A total of 71 volatile compounds were identified, 53 of which were annotated based on the GC-IMS database. These include 20 alcohols, 16 ketones, 10 aldehydes, four alkenes, one ester, one acid, and one furan. Using VOC fingerprinting and multivariate analysis, yak meats from different sources were distinctly categorized. Breed had the most significant impact on yak meat VOCs, followed by feeding method and then part. Six volatiles with a variable importance in projection value greater than one were identified as potential markers for distinguishing yak meat. This study offers insights into the flavor profile of yak meat from different sources and demonstrates the efficacy of GC-IMS and multivariate analysis in characterizing and discriminating meats. [ABSTRACT FROM AUTHOR]

Background: Clear cell renal cell carcinoma (ccRCC) comprises the majority, approximately 70–80%, of renal cancer cases and often remains asymptomatic until incidentally detected during unrelated abdominal imaging or at advanced stages. Currently, standardized screening tests for renal cancer are lacking, which presents challenges in disease management and improving patient outcomes. This study aimed to identify ccRCC-specific volatile organic compounds (VOCs) in the urine of ccRCC-positive patients and develop a urinary VOC-based diagnostic model. Methods: This study involved 233 pretreatment ccRCC patients and 43 healthy individuals. VOC analysis utilized stir-bar sorptive extraction coupled with thermal desorption gas chromatography/mass spectrometry (SBSE-TD-GC/MS). A ccRCC diagnostic model was established via logistic regression, trained on 163 ccRCC cases versus 31 controls, and validated with 70 ccRCC cases versus 12 controls, resulting in a ccRCC diagnostic model involving 24 VOC markers. Results: The findings demonstrated promising diagnostic efficacy, with an Area Under the Curve (AUC) of 0.94, 86% sensitivity, and 92% specificity. Conclusions: This study highlights the feasibility of using urine as a reliable biospecimen for identifying VOC biomarkers in ccRCC. While further validation in larger cohorts is necessary, this study's capability to differentiate between ccRCC and control groups, despite sample size limitations, holds significant promise. [ABSTRACT FROM AUTHOR]

BACKGROUND: Bursaphelenchus xylophilus, the causative agent of pine wilt disease (PWD), is an ever‐increasing threat to Pinus forests worldwide. This study aimed to develop biological control of PWD by the application of endophytic fungi isolated from healthy pine trees. RESULTS: We successfully isolated a novel endophytic fungal strain 1‐24‐2 from branches of healthy Pinus massoniana. The culture filtrates (CFs) of strain 1‐24‐2 exhibited strong nematicidal activity against Bursaphelenchus xylophilus, with a corrected mortality rate of 99.00%. Based on the morphological and molecular characteristics, the isolated strain 1‐24‐2 was identified as Chaetomium ascotrichoides. In the in‐planta assay, pine seedlings (2‐years‐old) treated with 1‐24‐2 CFs + pine wood nematode (T2) showed a significant control effect of 80%. A total of 24 toxic compounds were first identified from 1‐24‐2 CFs through gas chromatography–mass spectrometry (GC–MS) analysis, from which O‐methylisourea, 2‐chlorobenzothiazole, and 4,5,6‐trihydroxy‐7‐methylphthalide showed robust binding sites at Tyr119 against phosphoethanolamine methyltransferase (PMT) protein of Bursaphelenchus xylophilus by molecular docking approach and could be used as potential compounds for developing effective nematicides. Interestingly, strain 1‐24‐2 produces toxic volatile organic compounds (VOCs), which disturb the natural development process of B. xylophilus, whose total number decreased by up to 83.32% in the treatment group as compared to control and also reduced Botrytis cinerea growth by up to 71.01%. CONCLUSION: Our results highlight the potential of C. ascotrichoides 1‐24‐2 as a promising biocontrol agent with solid nematicidal activity against B. xylophilus. This is the first report of C. ascotrichoides isolated from P. massoniana exhibiting strong biocontrol potential against B. xylophilus in the world. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

AbstractA set of mono-metallic nanoparticles catalysts, including palladium, platinum, and gold supported on titania, were prepared via the sol-immobilization technique, and evaluated for the total oxidation of propane as a model reaction of volatile organic compounds (VOCs) oxidation, which is a wide-ranging group of organic pollutants that contribute to serious atmospheric problems. The results showed that 1 wt.% Pt/TiO2 was the most active catalyst toward CO2, as the catalyst was very active, and the complete conversion of propane was achieved with full selectivity toward CO2. The effect of the support type was investigated through the immobilization of platinum nanoparticles on CeO2 and γ-Al2O3. The results indicated that the catalytic activity follows the order 1% Pt/TiO2 > 1% Pt/CeO2 > 1% Pt/Al2O3. For the Pt/TiO2 catalyst, the influence of the calcination temperature and metal loading on the catalytic activity was investigated. There is a slight increase in the Pt particle size when raising the calcination temperature from 300 °C to 500 °C, which enhances the catalytic activity of 1% Pt/TiO2 at 500 °C. Furthermore, increasing the metal loading from 0.1 to 1 wt.% enhances the catalytic activity as a result of the increase in particle size. Different characterization techniques were utilized, including XRD, TEM, XPS, and MP-AES, to determine the structure-activity relationship, and together they indicate that the catalytic activity is influenced more by the particle size of Pt nanoparticles than by the oxidation state.

Photocatalysis has applications in various fields, such as in air purification devices and even in coatings, where it can be incorporated into paint formulations to take advantage of its air purification and self-cleaning properties. This report looks not only at the process of photocatalysis, but also at studies that have been carried out on its incorporation into coatings using titanium dioxide (TiO2). TiO2 is commercially available and can be synthesized in the laboratory to improve its performance in air purification and decontamination of various pollutants. In addition, studies into enhancing TiO2 semiconductor materials with a photocatalytic system, such as the inclusion of manganese, were emphasized. These studies presented findings on boosted decontamination performance, which is critical for enhancing indoor air quality through the elimination of harmful gases and organic compounds. Volatile organic compounds, such as formaldehyde, toluene, benzene, and NOx, have extremely toxic health effects. Every year, indoor and outdoor air pollution causes a significant number of deaths. Considering that people spend more than 80% of their time indoors, the filtration of indoor air is even more important. Therefore, this article presents some studies on the further development of photocatalytic materials and technologies for the commercial application of photocatalytic paints. Commercial photocatalytic paints containing TiO2 doped with magnesium (Mn), silicate paints and water-based styrene acrylic paints were investigated, focusing on their ability to reduce VOC emissions.

The adsorption of toxic and harmful gases through porous materials is an effective means of air pollution control. A multi-level porous carbon material with ultra-high-specific surface area was made based on rice husk biomass to improve the air pollution controlling efficiency and reduce its cost. The rice husk substrate was pretreated using T.viride spore suspension during the preparation of this material. This changes the proportion of various components in the matrix, thereby achieving an increase in the multi-level porous carbon material’s specific surface area. Its performance was analyzed through various means in the study. The results confirmed that when the activation treatment time was 60 minutes, the porous carbon material’s specific surface area was the highest, reaching 3714 m2/g. After 30 days of treatment with T.viride spore suspension, the cellulose content in rice husks decreased by about 40 g/kg. Compared to untreated porous carbon materials, after 20 days of treatment, the micropores and mesopores of these materials significantly increased. The research has successfully increased the multi-level porous carbon material’s specific surface area and achieved rapid absorption of atmospheric volatile organic compounds. The multi-level porous carbon material can enhance the air pollution controlling efficiency and reduce its cost.

Abstract Perennial grains, which remain productive for multiple years, rather than growing for only one season before harvest, have deep, dense root systems that can support a richness of beneficial microorganisms, which are mostly underexplored. In this work we isolated forty-three bacterial strains associated with the rhizosphere of the OK72 perennial wheat line, developed from a cross between winter common wheat and Thinopyrum ponticum. Identified using 16S rDNA sequencing, these bacteria were assessed for plant growth-promoting traits such as indole-3-acetic acid, siderophores and ACC-deaminase acid production, biofilm formation, and the ability to solubilize phosphate and proteins. Twenty-five strains exhibiting in vitro significant plant growth promoting traits, belong to wheat keystone genera Pseudomonas, Microbacterium, Variovorax, Pedobacter, Dyadobacter, Plantibacter, and Flavobacterium. Seven strains, including Aeromicrobium and Okibacterium genera, were able to promote root growth in a commercial annual wheat cultivar while strains from Pseudomonas genus inhibited the growth of Aspergillus flavus and Fusarium species, using direct antagonism assays. The same strains produced a high amount of 1-undecanol a volatile organic compound, which may aid in suppressing fungal growth. The study highlights the potential of these bacteria to form new commercial consortia, enhancing the health and productivity of annual wheat crops within sustainable agricultural practices.

• The incorporation of Co 3 O 4 enhances the full-spectrum absorption of the catalyst. • The Co 3 O 4 NPs are uniformly dispersed on the TiO 2 support. • The introduction of Ce brings in the advantageous dual redox cycles. • Co3+, Ti3+ and oxygen vacancies play important roles in toluene catalytic oxidation. • Light irradiation displays a promoting effect on catalytic activity. Cerium and cobalt loaded Co-Ce/TiO 2 catalyst prepared by impregnation method was investigated for photothermal catalytic toluene oxidation. Based on catalyst characterizations (XPS, EPR and H 2 -TPR), redox cycle between Co and TiO 2 (Co2+ + Ti4+ ↔ Co3+ + Ti3+) results in the formation of Co3+, Ti3+ and oxygen vacancies, which play important roles in toluene catalytic oxidation reaction. The introduction of Ce brings in the dual redox cycles (Co2+ + Ti4+ ↔ Co3+ + Ti3+, Co2+ + Ce4+ ↔ Co3+ + Ce3+), further promoting the elevation of reaction sites amount. Under full spectrum irradiation with light intensity of 580 mW/cm2, Co-Ce/TiO 2 catalyst achieved 96% of toluene conversion and 73% of CO 2 yield, obviously higher than Co/P25 and Co/TiO 2. Co-Ce/TiO 2 efficiently maintains 10-hour stability test under water vapor conditions and exhibits better photothermal catalytic performance than counterparts under different wavelengths illumination. Photothermal catalytic reaction displays improved activities compared with thermal catalysis, which is attributed to the promotional effect of light including photocatalysis and light activation of reactive oxygen species. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] Indoor air pollution, predominantly caused by volatile organic compounds (VOCs), poses significant health hazards when concentrations surpass critical thresholds. Using waste corn straw as carbon source and urea as nitrogen source, straw derived carbon aerogel (CAGH) loaded with g-C 3 N 4 H 2 O-N 2 -450–3 h was successfully prepared by hydrothermal and water-assisted calcination. Following water-assisted regulation, g-C 3 N 4 H 2 O-N 2 -450–3 h on CAGH exhibited a mixed structure comprising honeycomb and two-dimensional filaments, while the growth of g-C 3 N 4 H 2 O-N 2 -450–3 h was uniformly distributed on carbon aerogel in a line-surface combination fashion. This innovative binding method not only enhanced the loading capacity of g-C 3 N 4 and the mechanical elasticity of aerogel, but also exposed a large number of adsorption sites, resulting in a significant increase in its adsorption capacity for VOCs, exceeding that of commercial activated carbon (AC). In comparison to pure g-C 3 N 4 , CAGH exhibited an expanded photo-response range. Under the exposure of visible light, CAGH proved highly effective in eliminating 73.87 % of toluene. In addition, it has demonstrated efficient removal of formaldehyde and acetone VOCs with good cyclic stability. Therefore, this work aims to reduce the emission of pollutants at source and provide an effective and economical strategy for the preparation of clean building materials from renewable materials, with potential applications in the environmental field. [ABSTRACT FROM AUTHOR]

Introduction. For four years, SARS-CoV-2, the etiological agent of COVID-19, has been circulating among humans. By the end of the second year, an absence of immunologically naive individuals was observed, attributable to extensive immunization efforts and natural viral exposure. This study focuses on delineating the molecular and biological patterns that facilitate the persistence of SARS-CoV-2, thereby informing predictions on the epidemiological trajectory of COVID-19 toward refining pandemic countermeasures. The aim of this study was to describe the molecular biological patterns identified that contribute to the persistence of the virus in the human population. Materials and methods. For over three years since the beginning of the COVID-19 pandemic, molecular genetic monitoring of SARS-CoV-2 has been conducted, which included the collection of nasopharyngeal swabs from infected individuals, assessment of viral load, and subsequent whole-genome sequencing. Results. We discerned dominant genetic lineages correlated with rising disease incidence. We scrutinized amino acid substitutions across SARS-CoV-2 proteins and quantified viral loads in swab samples from patients with emerging COVID-19 variants. Our findings suggest a model of viral persistence characterized by 1) periodic serotype shifts causing substantial diminutions in serum virus-neutralizing activity ( 10-fold), 2) serotype-specific accrual of point mutations in the receptor-binding domain (RBD) to modestly circumvent neutralizing antibodies and enhance receptor affinity, and 3) a gradually increasing amount of virus being shed in mucosal surfaces within a single serotype. Conclusion. This model aptly accounts for the dynamics of COVID-19 incidence in Moscow. For a comprehensive understanding of these dynamics, acquiring population-level data on immune tension and antibody neutralization relative to genetic lineage compositions is essential.

Objectives To find possible relationship between asthma exacerbation and metabolomic profile of airways, assessed by non-invasive method – free volatile organic compounds (VOCs) in exhaled air in children. Material and Methods The study included 80 children aged 4–18 years with asthma: 42 children with a min. 3 asthma exacerbations in the past 12 months, and 38 children without a history of exacerbations in the past year. During the study visit, each patient was examined, medical history (including information regarding atopy and eosinophil blood count) was taken, spirometry and fractional exhaled nitric oxide (FeNO) were tested, an exhaled air sample was taken to test for the presence of VOCs, and the patient also completed standardized form – Asthma Control Questionnaire . Volatile organic compounds were measured by combined gas chromatography coupled to mass spectrometry. Results The obtained results of VOCs were correlated with the history of the disease. The 2 gas profiles were defined and they formed 2 clinically distinct clusters (p = 0.085). Cluster 2 was characterized for children with a higher number of bronchial asthma exacerbations and worse lung function parameters (predicted percentage forced expiratory volume in 1 s [FEV 1 ] [p = 0.023], FEV 1 / forced vital capacity ratio [FVC] [p = 0.0219]). The results were independent of the age, sex, BMI, atopy (house dust mite allergy) and eosinophil blood count. Conclusions The study findings suggest that a relative group of gases may be a useful predictor of having asthma exacerbations in children. Additionally, a single FeNO value was unlikely to be clinically useful in predicting asthma exacerbations in children. The VOCs profile reflecting the metabolism of the airway epithelium and local microbiota was associated with the course of asthma, which strongly justifies further prospective validation studies. Int J Occup Med Environ Health. 2024;37(3):351–59

New building construction is often counted as a source of indoor air pollution because of formaldehyde and volatile organic compounds (VOCs) emitted from new building materials, such as furnishings, wood, and finishings. The high levels of formaldehyde and VOCs in the early stage of new buildings could be linked to the negative health effects on occupants. The aim of this study is to examine the impacts of flush-out air flow rate and flush period in reducing formaldehyde and VOCs produced by building materials or furnishing of newly built residential buildings. Field measurements were conducted from September 2016 to August 2018 in nineteen newly built apartments to verify the effectiveness of the flush-out procedure. The field measurements showed that after the flush-out, the indoor concentrations of formaldehyde and VOCs in the newly built samples significantly decreased. The indoor concentrations of formaldehyde and TVOCs were reduced to about 61% and 41% of the initial concentration when the samples were flushed at 0.7ACH for nine days. The results of this study showed that the flush-out for a short term of below two weeks was more effective reducing the emission potential of VOCs than of formaldehyde. When the samples were flushed for more than seven days, the air change rates of the flushing did not significantly influence the reduction of indoor pollutants.

Abstract This study established a novel infield sensing approach based on detection of the volatile compound markers in skin secretions. This was based on analysis of volatile compounds in axillary sweat samples collected from RT-PCR-proven Coronavirus disease 2019 (COVID-19) positive and negative populations using gas chromatography-mass spectrometry (GC–MS). The analysis proposed the possible markers of the monoaromatic compounds and ethyl hexyl acrylate. A portable photo ionization detector (PID) incorporated with the selective material towards the marker compounds was then developed with the pressurized injection approach. This provided the accuracy of 100% in the research phase (n = 125). The developed approach was then applied for screening of 2207 COVID-19 related cases covering the periods of the Alpha, Beta, Delta and Omicron variants of SARS-CoV-2 infection in Bangkok, Thailand. This offered the sensitivity, specificity and accuracy ranges of 92–99, 93–98 and 95–97%, respectively.

Species within the primitive genus Magnolia may often produce specialized floral traits and behaviour to grab the attention of potential pollinators from their surroundings. These reproductive traits in plants undergo various selection pressures and frequently bring forth variations to adapt to the new habitat that may result in speciation. We have aimed to understand the floral traits, the functional role of floral parts, and the variable response of visitors in Magnolia grandiflora belonging to an ancient order Magnoliales. Our observations reveal that the floral traits of M. grandiflora resemble those of basal angiosperms, conforming to the primitive existence of the genus Magnolia. The inconsistency in floral form reflected that M. grandiflora has been experiencing various selection pressures from biotic and abiotic factors. Inconsistency in floral equations and diagrams reflect the structural variability in flowers, which can directly impact pollination and reproductive output. SEM images of pollen grains reveal that the pollen grains were monocolpate and boat-shaped in structure. GC-MS analysis showed that VOCs in stigmatic exudation of the flower were largely composed of terpene hydrocarbons such as Perthenine, β-Elemene, β-Caryophyllene, α-Humulene, Bicyclogermacrene, Germacrene A and D, etc. Beyond pollinators attraction, VOCs play a major role in repelling unwanted visitors and in improving the defensive mechanisms in Magnolia. Beetles, bees, and flies were found to be the active pollinators and the behaviour of bees indicates that bees were trying to replace the role of beetles in pollinating M. grandiflora. In summary, floral whorls were diversely functionalized to ensure maximum reproduction in M. grandiflora.

Abstract Characteristic volatile organic compounds (VOCs) are anticipated to be used for the identification of lung cancer cells. However, to date, consistent biomarkers of VOCs in lung cancer cells have not been obtained through direct comparison between cancer and healthy groups. In this study, we regulated the glycolysis, a common metabolic process in cancer cells, and employed solid phase microextraction gas chromatography mass spectrometry (SPME–GC–MS) combined with untargeted analysis to identify the characteristic VOCs shared by cancer cells. The VOCs released by three types of lung cancer cells (A549, PC-9, NCI-H460) and one normal lung epithelial cell (BEAS-2B) were detected using SPME–GC–MS, both in their resting state and after treatment with glycolysis inhibitors (2-Deoxy-d-glucose, 2-DG/3-Bromopyruvic acid, 3-BrPA). Untargeted analysis methods were employed to compare the VOC profiles between each type of cancer cell and normal cells before and after glycolysis regulation. Our findings revealed that compared to normal cells, the three types of lung cancer cells exhibited three common differential VOCs in their resting state: ethyl propionate, acetoin, and 3-decen-5-one. Furthermore, under glycolysis control, a single common differential VOC—acetoin was identified. Notably, acetoin levels increased by 2.60–3.29-fold in all three lung cancer cell lines upon the application of glycolysis inhibitors while remaining relatively stable in normal cells. To further elucidate the formation mechanism of acetoin, we investigated its production by blocking glutaminolysis. This interdisciplinary approach combining metabolic biochemistry with MS analysis through interventional synthetic VOCs holds great potential for revolutionizing the identification of lung cancer cells and paving the way for novel cytological examination techniques.

Biofilter technology has played a significant role over several decades in providing clean air through removal of Volatile Organic Compounds (VOCs) and odor causing chemicals such as hydrogen sulfide from industrial polluted airstreams. Biofilters where biological oxidation process takes place are designed and installed in numerous industrial facilities including chemical manufacturing, food processing, solid waste recycling and wastewater treatment plants to control emissions of VOCs, and odors in order to comply with the air emission regulations and to provide clean breathable air. Biofilter mathematical models under steady-state and transient conditions are essential in order to design, scale-up and predict biofilter performance under different operating conditions. Similarly, Artificial Intelligence (AI) through the use of Artificial Neural Network (ANN) modeling of biofiltration process is also becoming important. This research provides a detailed discussion and review of the recent (i.e., the last two decades) and important studies related to ANN, steady-state and transient biofilter models.

Biogenic volatile organic compounds (BVOCs) are regarded as important precursors for ozone and secondary organic aerosol, mainly from vegetation emissions. In the context of the expanding trend of vegetation greening, the development of high‐precision vegetation data and accurate BVOC emission estimates are essential to develop effective air pollution control measures. In this study, by integrating the multi‐source vegetation cover data, we established a high‐resolution vegetation distribution (HRVD) data set to develop a high spatio‐temporal resolution emission inventory and investigated the impact of different land cover data sets on emission simulation and impact of land cover change on BVOC emissions during 2001–2020. The annual total BVOC emissions in China for 2020 was 15.66 Tg, which were mainly from trees. The emissions simulated by CNLUCC and MODIS data sets were 1.53% and 1.72% higher than those simulated by HRVD data sets, respectively. The spatial distribution of emission differences was consistent with that of land cover differences. The simulated BVOC emissions by the HRVD data set had the best accuracy as they improved the bias between modeling and observation from 69.06% to 65.35% and decreased the underprediction of observations by a factor of 2.13 compared with simulation by MEGAN default vegetation data. The annual BVOC emissions caused by changing vegetation distribution and LAIv (LAI of vegetation covered surfaces) enhanced at a rate of 72.06 Gg yr−1 during 2001–2020. LAIv was the main driver of emission variations. The total OH reactivity of the resulted BVOC emissions increased at a rate of 1.59 s−1 yr−1, with isoprene contributed the most. Plain Language Summary: Biogenic Volatile organic compounds (BVOCs) are the key precursors of fine particulate matter and ozone, that mainly from vegetation emissions. To help to develop effective air pollution control measures in the context of expanding vegetation coverage for realizing carbon neutralization in China, it is urgent to develop highly precise vegetation data and accurately estimate BVOC emission. A high‐resolution vegetation distribution data set was established through integrating multi‐source vegetation cover data. Using it, the simulated annual BVOC emission in China was 15.66 Tg and mainly emitted from trees. Emissions from varied growth forms had different compound compositions. The BVOC emission simulated using the high‐resolution vegetation distribution data set we developed had better accuracy than that using the single vegetation databases. The annual BVOC emissions caused by changing vegetation cover and leaf area index (LAI) enhanced at a rate of 72.06 Gg yr−1 during 2001–2020. LAI was the main driver of BVOC emission variations. The interannual variation and its spatial pattern of the OH loss rates of BVOCs during 2001–2020 were consistent with that of BVOC emissions, especially isoprene. Key Points: Annual total BVOC emissions in China for 2020 was 15.66 Tg and emissions from varied growth forms had different compositionsBVOC emission inventory simulated by the developed high‐resolution vegetation distribution (HRVD) data set had better accuracyBVOC emission enhanced at a rate of 72.06 Gg yr−1 during 2001–2020 caused by land cover change, mainly driven by changing leaf area index [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) are typical pollutants with hazards for humans and the environment, which can be efficiently mitigated by catalytic combustion. Fe2O3‐based catalysts are a promising choice due to their low cost and strong redox ability. Several attempts have been made to promote the catalytic performance for Fe2O3‐based catalysts at low temperatures. This review summarizes the research progress on Fe2O3‐based catalysts for the oxidation of toluene, one of the most common and harmful VOC. Firstly, the structural properties and catalytic performances for Fe2O3‐based catalysts have been summarized, and the reaction mechanisms for toluene oxidation on the surface of Fe2O3‐based catalysts were detailed to comprehend the role of oxygen vacancies. Then, the modification for single Fe2O3 catalysts, including synthesis parameters, structure and morphology control, is introduced to reveal the correlation between physicochemical properties of catalysts and their activity for toluene oxidation. In addition, composite Fe2O3 catalysts, which can promote catalytic performance significantly by the synergetic effect between different components, were presented in detail. Moreover, waste‐derived Fe2O3 catalysts with sustainable merit as converting waste into worth have been discussed. Finally, the advanced machine learning tools, which are helpful in accelerating catalyst design, configuration optimization and reactivity prediction, have been introduced as an emerging research opportunity for the future. [ABSTRACT FROM AUTHOR]

Fungal phytopathogens represent a large and economically significant challenge to food production worldwide. Thus, the application of biocontrol agents can be an alternative. In the present study, we carried out biological, metabolomic, and genetic analyses of three endophytic isolates from nodules of Chamaecytisus albus, classified as Pseudomonas chlororaphis acting as antifungal agents. The efficiency of production of their diffusible and volatile antifungal compounds (VOCs) was verified in antagonistic assays with the use of soil-borne phytopathogens: B. cinerea, F. oxysporum, and S. sclerotiorum. Diffusible metabolites were identified using chromatographic and spectrometric analyses (HPTLC, GC-MS, and LC-MS/MS). The phzF, phzO, and prnC genes in the genomes of bacterial strains were confirmed by PCR. In turn, the plant growth promotion (PGP) properties (production of HCN, auxins, siderophores, and hydrolytic enzymes, phosphate solubilization) of pseudomonads were bioassayed. The data analysis showed that all tested strains have broad-range antifungal activity with varying degrees of antagonism. The most abundant bioactive compounds were phenazine derivatives: phenazine-1-carboxylic acid (PCA), 2-hydroxy-phenazine, and diketopiperazine derivatives as well as ortho-dialkyl-aromatic acids, pyrrolnitrin, siderophores, and HCN. The results indicate that the tested P. chlororaphis isolates exhibit characteristics of biocontrol organisms; therefore, they have potential to be used in sustainable agriculture and as commercial postharvest fungicides to be used in fruits and vegetables. [ABSTRACT FROM AUTHOR]

There has been a recent increase in the frequency of mass disaster events. Following these events, the rapid location of victims is paramount. Currently, the most reliable search method is scent detection dogs, which use their sense of smell to locate victims accurately and efficiently. Despite their efficacy, they have limited working times, can give false positive responses, and involve high costs. Therefore, alternative methods for detecting volatile compounds are needed, such as using electronic noses (e-noses). An e-nose named the 'NOS.E' was developed and has been used successfully to detect VOCs released from human remains in an open-air environment. However, the system's full capabilities are currently unknown, and therefore, this work aimed to evaluate the NOS.E to determine the efficacy of detection and expected sensor response. This was achieved using analytical standards representative of known human ante-mortem and decomposition VOCs. Standards were air diluted in Tedlar gas sampling bags and sampled using the NOS.E. This study concluded that the e-nose could detect and differentiate a range of VOCs prevalent in ante-mortem and decomposition VOC profiles, with an average LOD of 7.9 ppm, across a range of different chemical classes. The NOS.E was then utilized in a simulated mass disaster scenario using donated human cadavers, where the system showed a significant difference between the known human donor and control samples from day 3 post-mortem. Overall, the NOS.E was advantageous: the system had low detection limits while offering portability, shorter sampling times, and lower costs than dogs and benchtop analytical instruments. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic of 2020, marked by stringent lockdowns and reduced human activity, resulted in a significant decrease in air pollutant emissions. This study investigates the impact of these altered atmospheric conditions on human health by focusing on Volatile Organic Compounds (VOCs) such as benzene, toluene, and meta-xylene (BTX), comparing data from before, during, and after the pandemic lockdowns. The objectives were to assess changes in Total VOC (TVOC) concentrations and to evaluate the associated health risks, particularly Lifetime Cancer Risk (LCR) from benzene exposure. Analysis of the data revealed a notable reduction in TVOCs during the 2020 lockdown, with average concentrations of 12.15 ± 20.49 µg/m3 in 2019, 8.08 ± 5.50 µg/m3 in 2020, and 5.12 ± 7.56 µg/m3 in 2021. LCR values also fluctuated, with averages of 1.12 × 10−5, 1.23 × 10−5, and 6.91 × 10−6 or pre-pandemic, during-pandemic, and post-pandemic periods, respectively. The findings highlight the potential effectiveness of lockdowns in reducing air pollution and underscore the need for continued, targeted environmental policies to improve public health. [ABSTRACT FROM AUTHOR]

Transition metal oxides show high activity while still facing the challenges of low mineralization and poor durability in the ozone catalytic oxidation (OCO) of volatile organic compounds (VOCs). Improving the oxygen mobility and low-temperature reducibility of transition metal oxides was found to be an effective way to address the above challenges. Here, highly dispersed Ag was added to Mn3O4 via the co-precipitation oxalate route, and the obtained Ag/Mn3O4 exhibited higher mineralization and stability in benzene catalytic ozonation at room temperature. Compared to Mn3O4, the concentration of CO2 formed from benzene oxidation over Ag/Mn3O4 was significantly increased, from 585.4 ppm to 810.9 ppm, while CO generation was greatly suppressed to only one tenth of its original value (194 ppm vs. 19 ppm). In addition, Ag/Mn3O4 exhibited higher catalytic stability than Mn3O4. The introduction of Ag obviously improved the oxygen mobility and low-temperature reducibility of Mn3O4. Moreover, the highly dispersed Ag also promoted the activity of surface oxygen species and the chemisorption of benzene on Mn3O4. The above physicochemical properties contributed to the excellent catalytic performance and durability of Ag/Mn3O4. This research could shed light on the improvement in VOC mineralization via ozone catalytic oxidation. [ABSTRACT FROM AUTHOR]

In a project to preserve photographic archives in Southeast Asia, the authors sought to develop sustainable solutions with low environmental impact, avoiding air conditioning and using locally available materials. Dry cabinets were tested and implemented to store a glass plate negative collection that was rehoused in envelopes and boxes made locally. The project took just over a year to complete, and two years of monitoring environmental conditions have shown that relative humidity can be stabilized at low levels. However, the dry cabinets are airtight to limit the introduction of moisture and dust, preventing air exchange. In order to avoid the build-up of degradation by-products released by the stored materials, and in particular off-gassing of acetic acid from the cellulose acetate-based photographs, the use of an adsorbent is necessary. To achieve this, a cellulose-based composite with particles of a porous hybrid inorganic/ organic solid, denoted as a metal–organic framework (MOF), at a very high loading over 70% by weight and shaped as a sheet of paper, has been prepared and tested. This special paper maintains acetic acid-free air in the cabinets and also helps to reduce the energy consumption by reducing the need for cool storage. This MOF paper composite traps small carboxylic acids and was found to be an appropriate solution for maintaining clean air in the dry cabinets or any other confined space or enclosure. Additionally, it can also be designed to trap other noxious pollutants such as hydrogen sulfide or formaldehyde, by choosing other MOFs. [ABSTRACT FROM AUTHOR]

The effect of different methods of drying celery root enriched with beet juice by vacuum impregnation (VI) was studied. The process of convection drying, vacuum drying and freeze drying was carried out. Compared to dried indigenous celery, dry impregnated tissue was characterized by lower values of dry matter, L* and b* color parameters, as well as higher values of water activity, density and a* color parameter. In addition, VI reduced the drying time. Forty Volatile Organic Compounds (VOCs) were found in celery, while fifty-one VOCs were found in the profile of celery with beetroot juice. The innovative method of vacuum impregnation made it possible to produce a new type of product with changed properties and a variable VOCs profile. The best fit of the drying process kinetics was achieved by using the logistic model. Increasing the temperature during convection drying resulted in shorter drying time, increased values of dry matter, reduced the water activity value and altered VOCs. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) are significant pollutants in urban road dust, but their distribution and associated health risks remain unclear. VOC distribution in road dust from six distinct urban areas in Beijing Daxing District, China was systematically investigated. Eighteen VOCs were detected, with the highest load in commercial areas (7.73 μg/g), followed by industrial parks (6.38 μg/g), residential areas (3.35 μg/g), leisure areas (2.79 μg/g), traffic areas (2.01 μg/g) and urban-rural fringe (1.85 μg/g), much lower than in air and water phases. Typical VOCs in road dust include methyl tertiary butyl ether (MTBE) (0.82–1.24 μg/g), benzene series compounds (0.02–4.19 μg/g) and volatile halogenated alkanes (0.002-0.095 μg/g). Incomplete combustion of road vehicle fuels is the key source of VOCs. Particular attention was given to VOCs in typical sites within the urban-rural fringe, known for their unique pollution characteristics. The VOCs loads were ranked as follows: Gas Stations (2.61–2.62 μg/g) > Intersection (1.41 μg/g) > Main Road (1.34 μg/g) > University Gate (1.27 μg/g). Increased vehicle activity and frequent stalling contribute to higher VOCs accumulation in road dust. Health risk assessment indicates there is no appreciable non-carcinogenic risk associated with exposure to road dust VOCs. Further research should consider VOCs in the broader environmental context, including air and water. [ABSTRACT FROM AUTHOR]

Landfills for disposing of solid waste are designed, located, managed, and monitored facilities expected to comply with government regulations to prevent contamination of the surrounding environment. After the average life expectancy of a typical landfill (30 to 50 years), a large investment in the construction, operation, final closure, and 30-year monitoring of a new site is needed. In this case study, we provide a holistic explanation of the unexpected development of elevated temperature landfills (ETLFs), such as that in the city of Bristol (United States) on the border of the states of Virginia and Tennessee, including the initial role played by coal ash. Despite the increasing frequency of ETLF occurrence, there is limited knowledge available about their associated environmental problems. The study uses mixed (qualitative, quantitative, and mapping) methods to analyze (1) the levels of odoriferous reduced sulfur compounds, ammonia, and volatile organic compounds (VOCs) emitted, (2) the ratio of methane to carbon dioxide concentrations in five locations, which dropped from unity (normal landfill) to 0.565, (3) the location of gas well heads with gradients of elevated temperatures, and (4) the correlation of the filling rate (upward of ~12 m y−1) with depth for registered events depositing coal ash waste. The work identifies spatial patterns that support the conclusion that coal ash served as the initiator for an ETLF creation. The case of the city of Bristol constitutes an example of ETLFs with elevated temperatures above the regulatory United States Environmental Protection Agency (EPA) upper threshold (65 °C), having alongside low methane emissions, large production of leachate, land subsidence, and a large production of organic compounds. Such landfills suffer abnormal chemical reactions within the waste mass that reduce the life expectancy of the site. Residents in such communities suffer intolerable odors from fugitive emissions and poor air quality becomes prominent, affecting the well-being and economy of surrounding populations. Conclusive information available indicates that the Bristol landfill has been producing large amounts of leachate and hazardous gases under the high pressures and temperatures developed within the landfill. A lesson learned, which should be used to prevent this problem in the future, is that the early addition of coal ash into the landfill would have catalyzed the process of ETLF creation. The work considers the public health risks and socioeconomic problems of residents exposed to emissions from an ETLF and discusses the efforts needed to prevent further incidents in other locations. [ABSTRACT FROM AUTHOR]