Volatile organic compounds (VOCs) are key precursors for secondary organic aerosols (SOA) and ozone, imposing severe impacts on human health and environment. Considering the massive coal consumption, ...coal fired power plants (CFPPs) in China are non-negligible VOCs contributors, whose emission characteristics remain inadequately understood. Here, we investigated emission characteristics of 117 VOCs by field tests in four typical CFPPs, and a latest localized CFPPs source profile was compiled by integrating literature reviews. Then speciated-VOCs emission inventories for 2018–2022 were established based on dynamic emission factors and unit-level activity data. The results suggested that oxygenated VOCs (OVOCs) constituted the dominant group (76.5 %), with propionaldehyde (32.0 %) and formaldehyde (24.5 %) being the predominant species. OVOCs (93.2 %) and aromatics (77.4 %) were identified as the primary contributors to ozone and SOA, respectively. Driven by both the rise in coal consumption and technological advancements, nationwide VOCs emissions decreased from 83,393 t in 2018 to 53,251 t in 2022. Regional disparities and varying rates of decline in provincial emissions were evident, with VOCs emissions predominantly concentrated in northern and eastern provinces. Neimenggu, Shandong, Shanxi, Jiangsu, and Guangdong were identified as the top five provinces with the highest emissions. We believe this study would be conducive to a more comprehensive understanding and effective control of VOCs emissions from CFPPs in China.
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•Characteristics of 117 VOCs from CFPPs in China were investigated by field tests at four representative CFPPs.•Latest localized source profile for VOCs from CFPPs was established based on field tests and selected literature reviews.•The potential contributions of CFPP VOC emissions on secondary atmospheric pollutants were estimated.•The spatiotemporal variations in VOC emissions from CFPPs between 2018 and 2022 were analyzed.
Volatile organic compounds (VOCs) are the organic compounds having a minimum vapor pressure of 0.13 kPa at standard temperature and pressure (293 K, 101 kPa). Being used as a solvent for organic and ...inorganic compounds, they have a wide range of applications. Most of the VOCs are non-biodegradable and very easily become component of the environment and deplete its purity. It also deteriorates the water quality index of the water bodies, impairs the physiology of living beings, enters the food chain by bio-magnification and degrades, decomposes and manipulates the physiology of living organisms. To unveil the adverse impacts of volatile organic compounds (VOCs) and their rapid eruption and interference in the living world, a review has been designed. This review presents an insight into the currently available VOCs, their sources, applications, sampling methods, analytic procedures, imposition on the health of aquatic and terrestrial communities and their contamination of the environment. Elaboration has been done on representation of toxicological effects of VOCs on vertebrates, invertebrates, and birds. Subsequently, the role of environmental agencies in the protection of environment has also been illustrated.
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•VOCs are used as a solvent for organic and inorganic compounds; they have a wide range of applications.•Most of the VOCs are non-biodegradable and very easily become component of the environment and deplete itspurity.•VOCs deteriorate the water quality index of the water bodies and shows biomagnification in food chain.•Most of the VOCs impairs the physiology of living organisms.
One of the more important classes of potentially toxic indoor air chemicals are the Volatile Organic Compounds (VOCs). However, due to a limited understanding of the relationships between indoor ...concentrations of individual VOCs and health outcomes, there are currently no universal health-based guideline values for VOCs within Europe including the UK. In this study, a systematic search was conducted designed to capture evidence on concentrations, emissions from indoor sources, and health effects for VOCs measured in European residences.
We identified 65 individual VOCs, and the most commonly measured were aromatic hydrocarbons (14 chemicals), alkane hydrocarbons (9), aldehydes (8), aliphatic hydrocarbons (5), terpenes (6), chlorinated hydrocarbons (4), glycol and glycol ethers (3) and esters (2). The pathway of interest was inhalation and 8 individual aromatic hydrocarbons, 7 alkanes and 6 aldehydes were associated with respiratory health effects. Members of the chlorinated hydrocarbon family were associated with cardiovascular neurological and carcinogenic health effects and some were irritants as were esters and terpenes. Eight individual aromatic hydrocarbons, 7 alkanes and 6 aldehydes identified in European residences were associated with respiratory health effects. Of the 65 individual VOCs, 52 were from sources associated with building and construction materials (e.g. brick, wood products, adhesives and materials for flooring installation etc.), 41 were linked with consumer products (passive, electric and combustible air fresheners, hair sprays, deodorants) and 9 VOCs were associated with space heating, which may reflect the relatively small number of studies discussing emissions from this category of sources.
A clear decrease in concentrations of formaldehyde was observed over the last few years, whilst acetone was found to be one of the most abundant but underreported species. A new approach based on the operational indoor air quality surveillance will both reveal trends in known VOCs and identify new compounds.
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•A systematic search was conducted designed to capture evidence on concentrations, emissions from indoor sources, and health effects for VOCs measured in European and UK residences.•65 individual VOCs were identified.•Health end points from inhalation exposure to these VOCs were identified and discussed.•Reported emission rates from indoor sources will provide a valuable source as input for modelling tools.
In recent years, ozone (O3) is often the major pollutant during summertime in China. In order to better understand this problem, a long-term measurement of ozone (from 2006 to 2015) and its ...precursors (NOx and VOCs) as well as the photochemical parameter (UV radiation) in a mega city of China (Shanghai) is analyzed. The focus of this study is to investigate the trend of O3 and the causes of the O3 trend in large cities in China. In order to understand the relationship between the O3 precursors and O3 formation, two distinguished different sites of measurements are selected in the study, including an urbanization site (XJH-Xujiahui) and a remote site (DT-Dongtan). At the XJH site, there are high local emissions of ozone precursors (such as VOCs and NOx), which is suitable to study the effect of O3 precursors on O3 formation. In contrast, at the DT site, where there are low local emissions, the measured result can be used to analyze the background conditions nearby the city of Shanghai. The analysis shows that there were long-term trends of O3 and NOx concentrations at the urban site (XJH) from 2006 to 2015 (O3 increasing 67% and NOx decreasing 38%), while there were very small trends of O3 and NOx concentrations at the background site (DT). The analysis for causing the O3 trend suggests that (1) the large O3 increase at the urban area (XJH) was not due to the regional transport of O3; (2) the measurement of solar radiation had not significant trend during the period, and was not the major cause for the long-term O3 trend; (3) the measurement of VOCs had small change during the same period, suggesting that the trend in NOx concentrations at the urban site (XJH) was a major factor for causing the long-term change of O3 at the urban area of Shanghai. As a result, the O3 and NOx concentrations from 2006 to 2015 at the urban area of Shanghai were strongly anti-correlated, suggesting that the extremely high NOx concentration in the urban area depressed the O3 concentrations. It is interesting to note that the anti-correlation between O3 and NOx was in an un-linearly relationship. Under high O3 concentration condition, the ratio of ΔO3/ΔNOx was as large as −1.5. In contrast, under low O3 concentrations, the ratio of ΔO3/ΔNOx was only −0.2. This result suggested that when O3 concentration was high, it was more sensitive to NOx concentration, while when O3 concentration was low, it was less sensitive to NOx concentration. This study provides useful insights for better understanding the causes of the long-term-trend of regional O3 pollution nearby Shanghai, and has important implication for air pollution control in large cities in China. Due to the fact that NOx and VOCs are not only precursors for O3, but also are important precursors for particular matter (PM). If reduction of NOx leads to decrease in PM, but increase in O3, the NOx emission control become a very complicated issue and need to carefully design a comprehensive control method.
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•There are insignificant trends of O3 and NOx from 2006 to 2015 in a mega city (Shanghai).•The trends between O3 and NOx are strongly anti-correlated, indicating that the O3 is strongly depressed by high NOx.•The study suggests that the reduction of NOx can reduce PM2.5, while causes O3 to increase.•The NOx emission control becomes a very complicated issue and needs to carefully design a comprehensive control method.
The development of highly efficient and stable monolithic catalysts is essential for the removal of volatile organic compounds (VOCs). Copper foam (CF) is a potential ideal carrier for monolithic ...catalysts, but its low surface area is not conducive to dispersion of active species, thus reducing the interface interaction with active species. Herein, a vertically oriented Cu(OH)2 nanorod was in situ grown on the CF, which acted as the template and precursor to synthesize CoCu-MOF. The optimized catalyst (12CoCu-R) delivers excellent performance for acetone oxidation with a T90 of 195 °C. Impressively, the catalyst demonstrated satisfactory stability in long-term, cycle, water resistance, and high airspeed tests. Therefore, the present study provides a novel strategy for rationally designing efficient monolithic catalysts for VOC oxidation and other environmental applications.
Biogenic and anthropogenic organic vapors are crucial precursors of ozone and secondary organic aerosol (SOA) in the atmosphere. Here we conducted real-time measurements of gaseous organic compounds ...using a Vocus proton-transfer-reaction mass spectrometer (Vocus PTR-MS) at the Shanghuang mountain site (1128 m a.s.l.) in southeastern China during November 2022. Our results revealed a substantial impact of mixed biogenic and anthropogenic compounds at the mountain site, with oxygenated volatile organic compounds (OVOCs) comprising 74 % of the organic vapors. Two distinct periods, characterized by sunny days (P1) and persistent cloud events (P2), were observed. P1 exhibited higher concentrations of biogenic-related emissions compared to P2. For instance, isoprene, monoterpenes, and sesquiterpenes during P1 were 2.4–2.9 times higher than those during P2. OVOCs such as acetaldehyde, MVK + MACR, acetone, and MEK also showed higher concentrations during P1, indicating a dominant source from the photochemical oxidation of biogenic VOCs. Anthropogenic-related VOCs like benzene and toluene had higher concentrations during P2, displaying different diurnal cycles compared to P1. Our analysis identified four biogenic-related factors dominated by isoprene and sesquiterpene oxidation products, and two anthropogenic-related factors. During P1, biogenic sources contributed approximately 80 % to total organic compounds, while during P2, anthropogenic sources, particularly the aromatic-related factor, increased from 16 % to 35 %. Furthermore, a unique factor characterized by C2 amines and C3 amides and periodic plumes indicated the influence of industrial emissions from regional transport. The study highlights the significant variations in sources and compositions of gaseous organic compounds at regional mountain sites due to changes in meteorology and photochemical processing, potentially impacting regional ozone and SOA formation.
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•Organic vapors at a mountain site in southeastern China were first characterized by a Vocus PTR-MS.•Organic vapors at the regional background site comprised mainly oxygenated volatile organic compounds (74 %).•Largely different influences of biogenic and anthropogenic emissions between sunny and cloudy days.
Biogenic volatile emissions from the soil PEÑUELAS, J; ASENSIO, D; THOLL, D ...
Plant, cell & environment/Plant, cell and environment,
August 2014, Letnik:
37, Številka:
8
Journal Article
Recenzirano
Odprti dostop
Volatile compounds are usually associated with an appearance/presence in the atmosphere. Recent advances, however, indicated that the soil is a huge reservoir and source of biogenic volatile organic ...compounds (bVOCs), which are formed from decomposing litter and dead organic material or are synthesized by underground living organism or organs and tissues of plants. This review summarizes the scarce available data on the exchange of VOCs between soil and atmosphere and the features of the soil and particle structure allowing diffusion of volatiles in the soil, which is the prerequisite for biological VOC‐based interactions. In fact, soil may function either as a sink or as a source of bVOCs. Soil VOC emissions to the atmosphere are often 1–2 (0–3) orders of magnitude lower than those from aboveground vegetation. Microorganisms and the plant root system are the major sources for bVOCs. The current methodology to detect belowground volatiles is described as well as the metabolic capabilities resulting in the wealth of microbial and root VOC emissions. Furthermore, VOC profiles are discussed as non‐destructive fingerprints for the detection of organisms. In the last chapter, belowground volatile‐based bi‐ and multi‐trophic interactions between microorganisms, plants and invertebrates in the soil are discussed.
•Grafting methyl on the inner surface to enhance the water tolerance of HY.•Attachment of methyl leads to an enhancement of toluene adsorption capacity.•Outer surface silanization could not reduce ...the effect of water on toluene adsorption.•The adsorption behavior was investigated by adsorption kinetics and Y-N model.
Although Y zeolites are considered as a promising adsorbent for capturing volatile organic compounds (VOCs), its hydrophilic nature causes a significantly decrease in VOCs adsorption performance due to the pervasive water vapor in VOCs streams. Herein, a facile approach is proposed to significantly enhance the hydrophobicity by grafting methyl on the inner surface of Y zeolite. Attachment of methyl to the inner surface leads to a significant reduction in water affinity, resulting in a notable enhancement of toluene adsorption capacity in humid environment. The silanization process and the evolution of silane species are further elucidated through in-situ DRIFTS, NMR and TGA. Adsorption kinetics reveals that inner surface silanization reduces the adsorption rate constant of water by 50 %. However, the outer surface silanization with propyl is ineffective in mitigating the detrimental impact of water on the toluene adsorption. Moreover, Yoon-Nelson (Y-N) model analysis is applied to predict the breakthrough characteristics of fixed-bed adsorption and to evaluate the applicability in actual industry. In this work, this regioselective silanization approach could provide a facile strategy for controlling VOCs in humid environment.
Volatile organic compounds (VOCs) are low molecular weight molecules that tend to evaporate easily at room temperature because of their low boiling points. VOCs are emitted by all organisms; ...therefore, inter- and intra-kingdom interactions have been established, which are fundamental to the structuring of life on our planet. One of the most studied interactions through VOCs is between microorganism VOCs (mVOCs) and plants, including those of agricultural interest. The mVOC interactions generate various advantages for plants, ranging from promoting growth to the activation of defense pathways triggered by salicylic acid (systemic acquired resistance) and jasmonic acid (induced systemic resistance) to protect them against phytopathogens. Additionally, mVOCs directly inhibit the growth of phytopathogens, thereby providing indirect protection to plants. Among the current agricultural problems is the extensive use of chemicals, such as fertilizers, intended to combat production loss, and pesticides to combat phytopathogen infection. This causes problems in food safety and environmental pollution. Therefore, to overcome this problem, it is important to identify alternatives that do not generate environmental impacts, such as the application of mVOCs. This review addresses the protective effects of mVOCs emitted by microorganisms from different kingdoms and their implications in plant defense pathways.
Systemic propagation of immunity in plants Vlot, A. Corina; Sales, Jennifer H.; Lenk, Miriam ...
New phytologist,
February 2021, 2021-02-00, 20210201, Letnik:
229, Številka:
3
Journal Article
Recenzirano
Odprti dostop
Summary
Systemic immunity triggered by local plant–microbe interactions is studied as systemic acquired resistance (SAR) or induced systemic resistance (ISR) depending on the site of induction and ...the lifestyle of the inducing microorganism. SAR is induced by pathogens interacting with leaves, whereas ISR is induced by beneficial microbes interacting with roots. Although salicylic acid (SA) is a central component of SAR, additional signals exclusively promote systemic and not local immunity. These signals cooperate in SAR‐ and possibly also ISR‐associated signaling networks that regulate systemic immunity. The non‐SA SAR pathway is driven by pipecolic acid or its presumed bioactive derivative N‐hydroxy‐pipecolic acid. This pathway further regulates inter‐plant defense propagation through volatile organic compounds that are emitted by SAR‐induced plants and recognized as defense cues by neighboring plants. Both SAR and ISR influence phytohormone crosstalk towards enhanced defense against pathogens, which at the same time affects the composition of the plant microbiome. This potentially leads to further changes in plant defense, plant–microbe, and plant–plant interactions. Therefore, we propose that such inter‐organismic interactions could be combined in potentially highly effective plant protection strategies.
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