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Sample records for compounds voc emitted

  1. Characteristics of volatile organic compounds (VOCs) emitted from a petroleum refinery in Beijing, China

    NASA Astrophysics Data System (ADS)

    Wei, Wei; Cheng, Shuiyuan; Li, Guohao; Wang, Gang; Wang, Haiyan

    2014-06-01

    This study made a field VOCs (volatile organic compounds) measurement for a petroleum refinery in Beijing by determining 56 PAMS VOCs, which are demanded for photochemical assessment in US, and obtained the characteristics of VOCs emitted from the whole refinery and from its inner main devices. During the monitoring period, this refinery brought about an average increase of 61 ppbv in the ambient TVOCs (sum of the PAMS VOCs) at the refinery surrounding area, while the background of TVOCs there was only 10-30 ppbv. In chemical profile, the VOCs emitted from the whole refinery was characteristic by isobutane (8.7%), n-butane (7.9%), isopentane (6.3%), n-pentane (4.9%%), n-hexane (7.6%), C6 branched alkanes (6.0%), propene (12.7%), 1-butene (4.1%), benzene (7.8%), and toluene (5.9%). On the other hand, the measurement for the inner 5 devices, catalytic cracking units (CCU2 and CCU3), catalytic reforming unit (CRU), tank farm (TF), and wastewater treatment(WT), revealed the higher level of VOCs pollutions (about several hundred ppbv of TVOCs), and the individual differences in VOCs chemical profiles. Based on the measured speciated VOCs data at the surrounding downwind area, PMF receptor model was applied to identify the VOCs sources in the refinery. Then, coupling with the VOCs chemical profiles measured at the device areas, we concluded that CCU1/3 contributes to 25.9% of the TVOCs at the surrounding downwind area by volume, followed by CCU2 (24.7%), CRU (18.9%), TF (18.3%) and WT (12.0%), which was accordant with the research of US EPA (2008). Finally, ozone formation potentials of the 5 devices were also calculated by MIR technique, which showed that catalytic cracking units, accounting for about 55.6% to photochemical ozone formation, should be given the consideration of VOCs control firstly.

  2. Volatile organic compounds (VOCs) emitted from materials collected from buildings affected by microorganisms.

    PubMed

    Claeson, A-S; Sandström, M; Sunesson, A-L

    2007-03-01

    In this study mould damaged materials, including carpet, concrete, gypsum board, insulation, plastic, sand and wood, from 20 different buildings with moisture problems were collected. To study emissions from these materials both conventional methods for sampling, such as collection on Tenax TA, were used as well as complementary methods for sampling a wider spectrum of compounds, such as more volatile VOCs, amines and aldehydes. Analysis was carried out using gas chromatography and high-performance liquid chromatography. Mass spectrometry was used for identification of compounds. Alcohols and ketones were almost exclusively emitted from the materials after they had been wet for a week. Acids were also emitted in large quantities from wet gypsum board and plastic. No primary or secondary amines could be identified, but two tertiary amines, trimethylamine and triethylamine, were emitted from sand contaminated by Bacillus. The most common moulds found were Penicillium and Aspergillus. A multivariate method (partial least squares, PLS) was used to investigate the emission patterns from the materials. Materials with bacterial growth had a different VOC profile to those with only mould growth.

  3. [Characteristics of volatile organic compounds (VOCs) emitted from biofuel combustion in China].

    PubMed

    Li, Xing-Hua; Wang, Shu-Xiao; Hao, Ji-Ming

    2011-12-01

    Biofuel combustion is an important source of VOCs in China. Measurements were conducted to determine the characteristics of VOCs emitted from combustion of 5 typical biofuels. A carbon mass balance method was used to determine VOCs emission factors. The emission factors of the total VOCs from agricultural residues and wood combustion are (4.37 +/- 2.23) g x kg(-1) and (2.12 +/- 0.77) g x kg(-1), respectively. The emission factors of the agricultural residues are higher than those of the wood. Aromatics and aldehydes dominate the VOC emissions, both accounting for over 25% of the total VOC emissions. Distribution of VOC components from agricultural residues and wood combustion are similar, except for halogenated hydrocarbons and nitriles. On the basis of measured emission factors and the published maximum incremental reactivity values for VOCs, the ozone forming potential (OFPs) of speciated VOCs is estimated. The results indicate that the average OFPs of the total VOCs from agricultural residues and wood combustion are (16.9 +/- 8.2) g x kg(-1) and (10.8 +/- 4.9) g x kg(-1), respectively. The components with the highest OFPs values are: aldehydes, aromatics and alkenes/alkynes. Aldehydes accounts for over 50% of the total OFPs.

  4. Proton Transfer Reaction Time-of-Flight Mass Spectrometric (PTR-TOF-MS) determination of volatile organic compounds (VOCs) emitted from a biomass fire developed under stable nocturnal conditions

    NASA Astrophysics Data System (ADS)

    Brilli, Federico; Gioli, Beniamino; Ciccioli, Paolo; Zona, Donatella; Loreto, Francesco; Janssens, Ivan A.; Ceulemans, Reinhart

    2014-11-01

    Combustion of solid and liquid fuels is the largest source of potentially toxic volatile organic compounds (VOCs), which can strongly affect health and the physical and chemical properties of the atmosphere. Among combustion processes, biomass burning is one of the largest at global scale. We used a Proton Transfer Reaction “Time-of-Flight” Mass Spectrometer (PTR-TOF-MS), which couples high sensitivity with high mass resolution, for real-time detection of multiple VOCs emitted by burned hay and straw in a barn located near our measuring station. We detected 132 different organic ions directly attributable to VOCs emitted from the fire. Methanol, acetaldehyde, acetone, methyl vinyl ether (MVE), acetic acid and glycolaldehyde dominated the VOC mixture composition. The time-course of the 25 most abundant VOCs, representing ∼85% of the whole mixture of VOCs, was associated with that of carbon monoxide (CO), carbon dioxide (CO2) and methane (CH4) emissions. The strong linear relationship between the concentrations of pyrogenic VOC and of a reference species (i.e. CO) allowed us to compile a list of emission ratios (ERs) and emission factors (EFs), but values of ER (and EF) were overestimated due to the limited mixing of the gases under the stable (non-turbulent) nocturnal conditions. In addition to the 25 most abundant VOCs, chemical formula and concentrations of the residual, less abundant VOCs in the emitted mixture were also estimated by PTR-TOF-MS. Furthermore, the evolution of the complex combustion process was described on the basis of the diverse types of pyrogenic gases recorded.

  5. Are Some Fungal Volatile Organic Compounds (VOCs) Mycotoxins?

    PubMed Central

    Bennett, Joan W.; Inamdar, Arati A.

    2015-01-01

    Volatile organic compounds (VOCs) are carbon-compounds that easily evaporate at room temperature. Toxins are biologically produced poisons; mycotoxins are those toxins produced by microscopic fungi. All fungi emit blends of VOCs; the qualitative and quantitative composition of these volatile blends varies with the species of fungus and the environmental situation in which the fungus is grown. These fungal VOCs, produced as mixtures of alcohols, aldehydes, acids, ethers, esters, ketones, terpenes, thiols and their derivatives, are responsible for the characteristic moldy odors associated with damp indoor spaces. There is increasing experimental evidence that some of these VOCs have toxic properties. Laboratory tests in mammalian tissue culture and Drosophila melanogaster have shown that many single VOCs, as well as mixtures of VOCs emitted by growing fungi, have toxic effects. This paper describes the pros and cons of categorizing toxigenic fungal VOCs as mycotoxins, uses genomic data to expand on the definition of mycotoxin, and summarizes some of the linguistic and other conventions that can create barriers to communication between the scientists who study VOCs and those who study toxins. We propose that “volatoxin” might be a useful term to describe biogenic volatile compounds with toxigenic properties. PMID:26402705

  6. Are Some Fungal Volatile Organic Compounds (VOCs) Mycotoxins?

    PubMed

    Bennett, Joan W; Inamdar, Arati A

    2015-09-22

    Volatile organic compounds (VOCs) are carbon-compounds that easily evaporate at room temperature. Toxins are biologically produced poisons; mycotoxins are those toxins produced by microscopic fungi. All fungi emit blends of VOCs; the qualitative and quantitative composition of these volatile blends varies with the species of fungus and the environmental situation in which the fungus is grown. These fungal VOCs, produced as mixtures of alcohols, aldehydes, acids, ethers, esters, ketones, terpenes, thiols and their derivatives, are responsible for the characteristic moldy odors associated with damp indoor spaces. There is increasing experimental evidence that some of these VOCs have toxic properties. Laboratory tests in mammalian tissue culture and Drosophila melanogaster have shown that many single VOCs, as well as mixtures of VOCs emitted by growing fungi, have toxic effects. This paper describes the pros and cons of categorizing toxigenic fungal VOCs as mycotoxins, uses genomic data to expand on the definition of mycotoxin, and summarizes some of the linguistic and other conventions that can create barriers to communication between the scientists who study VOCs and those who study toxins. We propose that "volatoxin" might be a useful term to describe biogenic volatile compounds with toxigenic properties.

  7. Emission characteristics of VOCs emitted from consumer and commercial products and their ozone formation potential.

    PubMed

    Dinh, Trieu-Vuong; Kim, Su-Yeon; Son, Youn-Suk; Choi, In-Young; Park, Seong-Ryong; Sunwoo, Young; Kim, Jo-Chun

    2015-06-01

    The characteristics of volatile organic compounds (VOCs) emitted from several consumer and commercial products (body wash, dishwashing detergent, air freshener, windshield washer fluid, lubricant, hair spray, and insecticide) were studied and compared. The spray products were found to emit the highest amount of VOCs (~96 wt%). In contrast, the body wash products showed the lowest VOC contents (~1.6 wt%). In the spray products, 21.6-96.4 % of the VOCs were propane, iso-butane, and n-butane, which are the components of liquefied petroleum gas. Monoterpene (C10H16) was the dominant component of the VOCs in the non-spray products (e.g., body wash, 53-88 %). In particular, methanol was present with the highest amount of VOCs in windshield washer fluid products. In terms of the number of carbon, the windshield washer fluids, lubricants, insecticides, and hair sprays comprised >95 % of the VOCs in the range C2-C5. The VOCs in the range C6-C10 were predominantly found in the body wash products. The dishwashing detergents and air fresheners contained diverse VOCs from C2 to C11. Besides comprising hazardous VOCs, VOCs from consumer products were also ozone precursors. The ozone formation potential of the consumer and commercial spray products was estimated to be higher than those of liquid and gel materials. In particular, the hair sprays showed the highest ozone formation potential.

  8. VOLATILE ORGANIC COMPOUNDS (VOCS) CHAPTER 31.

    EPA Science Inventory

    The term "volatile organic compounds' (VOCs) was originally coined to refer, as a class, to carbon-containing chemicals that participate in photochemical reactions in the ambient (outdoor) are. The regulatory definition of VOCs used by the U.S. EPA is: Any compound of carbon, ex...

  9. VOLATILE ORGANIC COMPOUNDS (VOCS) CHAPTER 31.

    EPA Science Inventory

    The term "volatile organic compounds' (VOCs) was originally coined to refer, as a class, to carbon-containing chemicals that participate in photochemical reactions in the ambient (outdoor) are. The regulatory definition of VOCs used by the U.S. EPA is: Any compound of carbon, ex...

  10. Head-space, small-chamber and in-vehicle tests for volatile organic compounds (VOCs) emitted from air fresheners for the Korean market.

    PubMed

    Jo, Wan-Kuen; Lee, Jong-Hyo; Kim, Mo-Keun

    2008-02-01

    The present study investigated the emission characteristics of gel-type air fresheners (AFs), using head-space, small-chamber, and in-vehicle tests. Five toxic or hazardous analytes were found in the headspace phase of AFs (toluene, benzene, ethyl benzene, and m,p-xylene) at a frequency of more than 50%. Limonene and linalool, which are known to be unsaturated ozone-reactive VOCs, were detected at a frequency of 58 and 35%, respectively. The empirical model fitted well with the time-series concentrations in the chamber, thereby suggesting that the empirical model was suitable for testing emissions. Limonene exhibited the highest emission rate, followed by m,p-xylene, toluene, ethyl benzene, and benzene. For most target VOCs, higher air change per hour (ACH) levels exhibited increased emission rates. In contrast, higher ACH levels resulted in lower chamber concentrations. The mean concentration of limonene was significantly higher in passenger cars with an AF than without. For other target compounds, there were no significant differences between the two conditions tested. Consequently, it was suggested that unlike limonene, the emission strength for aromatic compounds identified in the chamber tests was not strong enough to elevate in-vehicle levels.

  11. [Study on the chemical compositions of VOCs emitted by cooking oils based on GC-MS].

    PubMed

    He, Wan-Qing; Nie, Lei; Tian, Gang; Li, Jing; Shao, Xia; Wang, Min-Yan

    2013-12-01

    Volatile organic compounds (VOCs) are key precursors of ozone and secondary organic aerosols in air, and the differences in the compositions of VOCs lead to their different contribution to atmospheric reaction. Cooking oil fume is one of the important sources of atmospheric VOCs, and its chemical compositions are distinct under different conditions of oil types, food types, cooking methods and heating temperatures etc. In this study, the production of cooking oil fume was simulated by heating typical pure vegetable oils (peanut oil, sunflower oil, soybean oil, olive oil and blend oil) at different temperatures in beakers to investigate the chemical compositions of VOCs. The emitted VOCs were sampled with a Tenax adsorption tube and analyzed using GC-MS after thermal desorption. According to spectral library search and map analysis, using area normalized semi-quantitative method, preliminary qualitative and quantitative tests were conducted for the specific components of VOCs under different conditions.

  12. Volatile organic compound (VOC) emissions during malting and beer manufacture

    NASA Astrophysics Data System (ADS)

    Gibson, Nigel B.; Costigan, Gavin T.; Swannell, Richard P. J.; Woodfield, Michael J.

    Estimates have been made of the amounts of volatile organic compounds (VOCs) released during different stages of beer manufacture. The estimates are based on recent measurements and plant specification data supplied by manufacturers. Data were obtained for three main manufacturing processes (malting, wort processing and fermentation) for three commercial beer types. Some data on the speciation of emitted compounds have been obtained. Based on these measurements, an estimate of the total unabated VOC emission. from the U.K. brewing industry was calculated as 3.5 kta -1, over 95% of which was generated during barley malting. This value does not include any correction for air pollution control.

  13. VOLATILE ORGANIC COMPOUNDS (VOC) RECOVERY ...

    EPA Pesticide Factsheets

    The purpose of the seminar was to bring researchers, technology developers, and industry representatives together to discuss recovery technologies and techniques for VOCs. The seminar focused on the specific VOC recovery needs of industry and on case studies that summarize effective VOC product recovery techniques applicable to air, water, and solid waste. The case studies highlighted examples in which existing and new recovery technologies resulted in significant cost savings to industry. The seminar focused on the following key issues:. Status and future direction of EPA< DOE, and other major research programs.. What are the latest technology innovations in VOC treatment and recovery?. Performance and cost effectiveness of VOC recovery techniques.. How are recovery techniques applied to air, water, and solid waste?Presenters were from industry, academia, EPA, and various consulting firms. The presentations were followed by several facilitated breakout sessions; these sessions allowed participants an opportunity to discuss their needs and opinions on VOC recovery trends, research, and other issues.This document contains summaries of the presentations and discussions during the seminar. It does not constitute an actual proceedings, since the presentations were informal and no written versions were required. The list of participants and contact information are included in Appendix A. Information

  14. Study of the dispersion of VOCs emitted by a municipal solid waste landfill

    NASA Astrophysics Data System (ADS)

    Chiriac, Rodica; Carré, Jean; Perrodin, Yves; Vaillant, Hervé; Gasso, Santiago; Miele, Philippe

    The dispersion of VOCs emitted by a municipal solid waste landfill was studied for a period of over one year. Sixteen VOCs were monitored: linear alkanes from C 7 to C 11, BTEX, trimethylbenzene, trichlorethylene, tetrachlorethylene, α and β-pinenes, limonene. The analytical procedure was first comprised of static long-term sampling of about 2 months using radial diffusion Radiello tubes containing activated carbon, followed by extraction by solvent ( i.e. CS 2) and GC/MS analysis. The results were initially analysed on the basis of the total concentration of the quantified VOCs, then by examining the concentrations of certain selected compounds. The influence of different parameters such as operating conditions, meteorological conditions and site morphology was highlighted on the basis of total VOC concentrations. In order to study the VOC's dispersion more closely, 5 compounds were chosen: toluene, benzene, limonene, and the sum trichlorethylene + tetrachlorethylene, as a "marker", to verify the origin of the VOCs emitted. The results showed that the main source of VOCs is the open cell and lead to different hypotheses on interferences from neighbouring sources and to the proposal of solutions to limit the emission of VOCs and their dispersion. To our knowledge, this type of study has not been accomplished until this day.

  15. Emission of volatile organic compounds (VOCs) from PVC floor coverings.

    PubMed

    Wiglusz, R; Igielska, B; Sitko, E; Nikel, G; Jarnuszkiewicz, I

    1998-01-01

    In this study 29 PVC floor coverings were tested for emission of vinyl chloride (VC) and other volatile organic compounds (VOCs). A study on the effect of higher temperature on emission of VOCs from newly manufactured PVC flooring was also carried out. The study was conducted in climatic chamber, according to Polish Standard PN-89/Z-04021. GC method was used for analyzing of the compounds emitted. VC was not emitted from any of the floorings tested. Other VOCs were emitted in different concentrations. The influence of temperature on emission was conducted at temperatures of 23 degrees C and 35 degrees C from 2 hrs up to 180 days after introduction of materials in the chamber. The increase of temperature caused increase of total volatile organic compounds (TVOC) emission during 24 hrs of experiment. Then the emission was comparable for both temperatures. After 9 days emission of identified and unidentified compounds (TVOC) showed a rapid decay and stayed on very low level during a few months. The study conducted showed that PVC floorings after 10 days of installation in the room should not be source of indoor air contamination.

  16. Sources of Volatile Organic Compounds (VOCs) in the UAE

    NASA Astrophysics Data System (ADS)

    Abbasi, Naveed; Majeed, Tariq; Iqbal, Mazhar; Riemer, Daniel; Apel, Eric; Lootah, Nadia

    The gas chromatography-flame ionization detection/mass spectrometry system has been used to identify major volatile organic compounds (VOCs) sources in the UAE (latitude 24.45N; longitude 54.22E). VOCs are emitted from an extensive number of sources in urban environments including fuel production, distribution, and consumption. Transport sources contribute a substantial portion of the VOC burden to the urban atmosphere in developed regions. UAE is located at the edge of the Persian Gulf and is highly affected by emissions from petrochemical industries in neighbouring Saudi Arabia, Qatar, and Iran. VOCs emerging from these industries can be transported to the UAE with jet streams. The analysis of the collected air samples at three locations in Sharjah, UAE during the autumn and winter seasons indicates the presence of more than 100 VOC species. The concentrations of these species vary in magnitudes but the most prominent are: acetylene, ethane, propane, butane, pentane, benzene, and toluene. The possible tracers for various emission sources have also been identified such as 2-methylpentane, 1, 3-butadiene and 2, 2-dimethlybutane for vehicle exhaust, the light hydrocarbons, namely n-butane, trans-2-butene, and n-pentane for gasoline vapor, and n-nonane, n-decane, and n-undecane for diesel vapor and asphalt application processes. As various emission sources are characterized by overlapping VOC species, the ratio of possible VOC tracers are used to quantify the contribution of different sources. Our aim in this paper is to explore and discuss possible impacts of transported emissions on the local VOC emission inventory from various sources for the UAE. This work is partially supported by Office of Development and Alumni Affairs at the American University of Sharjah, U.A.E.

  17. [Study on control and management for industrial volatile organic compounds (VOCs) in China].

    PubMed

    Wang, Hai-Lin; Zhang, Guo-Ning; Nei, Lei; Wang, Yu-Fei; Hao, Zheng-Ping

    2011-12-01

    Volatile organic compounds (VOCs) emitted from industrial sources account for a large percent of total anthropogenic VOCs. In this paper, VOCs emission characterization, control technologies and management were discussed. VOCs from industrial emissions were characterized by high intensity, wide range and uneven distribution, which focused on Bejing-Tianjin Joint Belt, Shangdong Peninsula, Yangtze River Delta and the Pearl River Delta. The current technologies for VOCs treatment include adsorption, catalytic combustion, bio-degradation and others, which were applied in petrochemical, oil vapor recovery, shipbuilding, printing, pharmaceutical, feather manufacturing and so on. The scarcity of related regulations/standards plus ineffective supervision make the VOCs management difficult. Therefore, it is suggested that VOCs treatment be firstly performed from key areas and industries, and then carried out step by step. By establishing of actual reducing amount control system and more detailed VOCs emission standards and regulations, applying practical technologies together with demonstration projects, and setting up VOCs emission registration and classification-related-charge system, VOCs could be reduced effectively.

  18. Characterization of low-VOC latex paints: Volatile organic compound content, VOC and aldehyde emissions, and paint performance. Final report, January 1997--January 1999

    SciTech Connect

    Fortmann, R.; Lao, H.C.; Ng, A.; Roache, N.

    1999-04-01

    The report gives results of laboratory tests to evaluate commercially available latex paints advertised as `low-odor,` `low-VOC (volatile organic compound),` or `no-VOC.` Measurements were performed to quantify the total content of VOCs in the paints and to identify the predominant VOCs and aldehydes in the emissions following application to test substrates. The performance of the paints was evaluated and compared to that of commonly used conventional latex paints by American Society for Testing and Materials (ASTM) standard methods that measured parameters such as scrubbability, cleanability, and hiding power. The report describes the paints that were tested, the test methods, and the experimental data. Results are presented that can be used to evaluate the low-odor/low-VOC paints as alternatives to conventional latex wall paints that contain and emit higher concentrations of VOCs.

  19. Gastrophysa polygoni herbivory on Rumex confertus: Single leaf VOC induction and dose dependent herbivore attraction/repellence to individual compounds

    USDA-ARS?s Scientific Manuscript database

    We report large induction (> 65fold increases) of volatile organic compounds (VOCs) emitted from a single leaf of the invasive weed mossy sorrel, Rumex confertus Willd. (Polygonaceae), by herbivory of the dock leaf beetle, Gastrophysa polygoni L. (Coleoptera: Chrysomelidae). The R. confertus VOC ble...

  20. Pollution profiles and health risk assessment of VOCs emitted during e-waste dismantling processes associated with different dismantling methods.

    PubMed

    An, Taicheng; Huang, Yong; Li, Guiying; He, Zhigui; Chen, Jiangyao; Zhang, Chaosheng

    2014-12-01

    Pollution profiles of typical volatile organic compounds (VOCs) emitted during dismantling of various printed circuit board assemblies (PCBAs) of e-wastes using different methods were comparatively investigated in the real e-waste dismantling workshops in South China in April 2013. Similar pollution profiles and concentrations of VOCs were observed between dismantling mobile phone and hard disk PCBAs by using electric blowers and between dismantling television and power supplier PCBAs using electric heating furnaces. Aromatic hydrocarbons (accounting for >60% of the sum of VOCs) were the dominant group during using electric blowers, while aromatic (accounting for >44% of the sum of VOCs) and halogenated hydrocarbons (accounting for >48% of the sum of VOCs) were the two dominant groups which contributed equally using electric heating furnaces. However, the distribution profiles of VOCs emitted during dismantling of televisions, hard disks and micro motors using rotary incinerators varied greatly, though aromatic hydrocarbons were still the dominant group. The combustion of e-wastes led to the most severe contamination of VOCs, with total VOCs (3.3×10(4) μg m(-3)) using rotary incinerators about 190, 180, 139, and 40 times higher than those using mechanical cutting, electric soldering iron, electric blower, and electric heating furnace, respectively. Both cancer and non-cancer risks existed for workers due to exposure to on-site emitted VOCs in all workshops especially in those using rotary incinerators according to the USEPA methodology, whereas only cancer risks existed in rotary incinerator workshops according to the American Conference of Industrial Hygienists methodology. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Biomass Burning Contributions to Ambient Volatile Organic Compounds (VOCs) in the Harvest Season in Beijing, China

    NASA Astrophysics Data System (ADS)

    Wu, R.; Xie, S.

    2015-12-01

    Volatile organic compounds (VOCs) play a fundamental role in the tropospheric chemistry as key precursors of ozone and secondary organic aerosol (SOA), and many VOC species have an adverse impact on human health. Therefore, VOCs are of great concern. Biomass burning, which is recognized as an important source of VOCs in China, has a significant effect on air pollution and climate change. Recent studies have reported some source profiles of VOCs emitted from biomass burning in China, and emission inventories have also been developed to estimate the biomass burning emissions. Nevertheless, very little is known about the emission characteristics of biomass burning, nor its contributions to ambient VOCs. This work presents the results from a continuous measurement of 108 VOC compounds by an online GC-MS/FID system at a receptor site in Beijing from October 1-14, 2014. Several biomass burning plumes were identified by extremely high level of acetonitrile, which is an excellent signature of biomass burning. The emission ratios of six VOCs species relative to acetonitrile were determined by enhancement ratio method. The contributions of biomass burning to ambient VOCs were also explored. Results show that the mixing ratios of ambient VOCs in biomass burning days were over twice as that in non-burning days. And biomass burning accounted for 25.1% (benzene), 24.6% (toluene), 18.8% (acetone), 24.9% (MEK), 29.4% (MVK), and 18.2% (n-hexanal) of the ambient mixing ratios, respectively. PMF analysis indicated that the contributions of biomass burning to VOCs increased from 5.5% to 12.7% on average in biomass burning days, which revealed that the high level of ambient VOCs in Beijing during this period can be partly attributed to extensive biomass burning. Our study will be helpful to better understand biomass burning emissions in China, as well as to explore the contributions of biomass burning to haze formation in the harvest season.

  2. Catalytic oxidation of volatile organic compounds (VOCs) - A review

    NASA Astrophysics Data System (ADS)

    Kamal, Muhammad Shahzad; Razzak, Shaikh A.; Hossain, Mohammad M.

    2016-09-01

    Emission of volatile organic compounds (VOCs) is one of the major contributors to air pollution. The main sources of VOCs are petroleum refineries, fuel combustions, chemical industries, decomposition in the biosphere and biomass, pharmaceutical plants, automobile industries, textile manufacturers, solvents processes, cleaning products, printing presses, insulating materials, office supplies, printers etc. The most common VOCs are halogenated compounds, aldehydes, alcohols, ketones, aromatic compounds, and ethers. High concentrations of these VOCs can cause irritations, nausea, dizziness, and headaches. Some VOCs are also carcinogenic for both humans and animals. Therefore, it is crucial to minimize the emission of VOCs. Among the available technologies, the catalytic oxidation of VOCs is the most popular because of its versatility of handling a range of organic emissions under mild operating conditions. Due to that fact, there are numerous research initiatives focused on developing advanced technologies for the catalytic destruction of VOCs. This review discusses recent developments in catalytic systems for the destruction of VOCs. Review also describes various VOCs and their sources of emission, mechanisms of catalytic destruction, the causes of catalyst deactivation, and catalyst regeneration methods.

  3. VOLATILE ORGANIC COMPOUNDS (VOC) RECOVERY SEMINAR

    EPA Science Inventory

    The purpose of the seminar was to bring researchers, technology developers, and industry representatives together to discuss recovery technologies and techniques for VOCs. The seminar focused on the specific VOC recovery needs of industry and on case studies that summarize effec...

  4. VOLATILE ORGANIC COMPOUNDS (VOC) RECOVERY SEMINAR

    EPA Science Inventory

    The purpose of the seminar was to bring researchers, technology developers, and industry representatives together to discuss recovery technologies and techniques for VOCs. The seminar focused on the specific VOC recovery needs of industry and on case studies that summarize effec...

  5. Volatile Organic Compound (VOC) Emissions from Dairy Cows and Their Waste

    NASA Astrophysics Data System (ADS)

    Shaw, S.; Holzinger, R.; Mitloehner, F.; Goldstein, A.

    2005-12-01

    Biogenic VOCs are typically defined as those directly emitted from plants, but approximately 6% of global net primary production is consumed by cattle that carry out enteric fermentation and then emit VOCs that could also be considered biogenic. Current regulatory estimates suggest that dairy cattle in central California emit VOCs at rates comparable to those from passenger vehicles in the region, and thus contribute significantly to the extreme non-attainment of ozone standards there. We report PTR-MS measurements of ammonia and VOCs, and cavity-enhanced-absorption gas analyzer (Los Gatos Research, Inc.) measurements of CH4, emitted from dairy cattle in various stages of pregnancy/lactation and their waste. Experiments were conducted in chambers at UC Davis that simulate freestall cow housing conditions. CH4 fluxes ranged from 125-374 lb/cow/year. The compounds with the highest fluxes from '3 cows+waste' treatments were: ammonia (1-18), methanol (0-2.3), acetone+propanal (0.2-0.7), dimethylsulfide (0-0.4), and mass 109 (likely ID = p-cresol; 0-0.3) in lb/cow/year. Mass 60 (likely ID = trimethylamine) and acetic acid were also abundant. There were 10s of additional compounds with detectable, but small, emissions. A few compounds that were likely emitted (i.e. ethanol, formaldehyde, and dimethylamine) were not quantified by the PTR-MS. The total flux for all measured organic gases (TOG = CH4 + PTR-MS VOCs(including acetone+propanal)) averaged 246±45 lb/cow/year for '3 cows+waste' treatments, and was dominated by methane (>98%). TOG flux for 'waste only' treatments averaged 1.1±0.1 lb/cow/year, and was instead dominated by VOC (>84%). The PTR-MS VOCs as a percent of TOG (0.6±0.2%) emitted from '3 cows+waste' treatments in chamber conditions was a factor of 10 smaller than that currently estimated by the California Air Resources Board. In addition, the ozone forming potentials of the most abundant VOCs are only about 10% those of typical combustion or plant

  6. Field observations of volatile organic compound (VOC) exchange in red oaks

    NASA Astrophysics Data System (ADS)

    Cappellin, Luca; Algarra Alarcon, Alberto; Herdlinger-Blatt, Irina; Sanchez, Juaquin; Biasioli, Franco; Martin, Scot T.; Loreto, Francesco; McKinney, Karena A.

    2017-03-01

    Volatile organic compounds (VOCs) emitted by forests strongly affect the chemical composition of the atmosphere. While the emission of isoprenoids has been largely characterized, forests also exchange many oxygenated VOCs (oVOCs), including methanol, acetone, methyl ethyl ketone (MEK), and acetaldehyde, which are less well understood. We monitored total branch-level exchange of VOCs of a strong isoprene emitter (Quercus rubra L.) in a mixed forest in New England, where canopy-level fluxes of VOCs had been previously measured. We report daily exchange of several oVOCs and investigated unknown sources and sinks, finding several novel insights. In particular, we found that emission of MEK is linked to uptake of methyl vinyl ketone (MVK), a product of isoprene oxidation. The link was confirmed by corollary experiments proving in vivo detoxification of MVK, which is harmful to plants. Comparison of MEK, MVK, and isoprene fluxes provided an indirect indication of within-plant isoprene oxidation. Furthermore, besides confirming bidirectional exchange of acetaldehyde, we also report for the first time direct evidence of benzaldehyde bidirectional exchange in forest plants. Net emission or deposition of benzaldehyde was found in different periods of measurements, indicating an unknown foliar sink that may influence atmospheric concentrations. Other VOCs, including methanol, acetone, and monoterpenes, showed clear daily emission trends but no deposition. Measured VOC emission and deposition rates were generally consistent with their ecosystem-scale flux measurements at a nearby site.

  7. First Characterisation of Volatile Organic Compounds Emitted by Banana Plants

    PubMed Central

    Berhal, Chadi; De Clerck, Caroline; Fauconnier, Marie-Laure; Levicek, Carolina; Boullis, Antoine; Kaddes, Amine; Jijakli, Haïssam M.; Verheggen, François; Massart, Sébastien

    2017-01-01

    Banana (Musa sp.) ranks fourth in term of worldwide fruit production, and has economical and nutritional key values. The Cavendish cultivars correspond to more than 90% of the production of dessert banana while cooking cultivars are widely consumed locally around the banana belt production area. Many plants, if not all, produce Volatile Organic Compounds (VOCs) as a means of communication with their environment. Although flower and fruit VOCs have been studied for banana, the VOCs produced by the plant have never been identified despite their importance in plant health and development. A volatile collection methodology was optimized to improve the sensitivity and reproducibility of VOCs analysis from banana plants. We have identified 11 VOCs for the Cavendish, mainly (E,E)-α-farnesene (87.90 ± 11.28 ng/μl), methyl salicylate (33.82 ± 14.29) and 6-methyl-5-hepten-2-one (29.60 ± 11.66), and 14 VOCs for the Pacific Plantain cultivar, mainly (Z,E)-α-farnesene (799.64 ± 503.15), (E,E)-α-farnesene (571.24 ± 381.70) and (E) β ocimene (241.76 ± 158.49). This exploratory study paves the way for an in-depth characterisation of VOCs emitted by Musa plants. PMID:28508885

  8. First Characterisation of Volatile Organic Compounds Emitted by Banana Plants.

    PubMed

    Berhal, Chadi; De Clerck, Caroline; Fauconnier, Marie-Laure; Levicek, Carolina; Boullis, Antoine; Kaddes, Amine; Jijakli, Haïssam M; Verheggen, François; Massart, Sébastien

    2017-05-16

    Banana (Musa sp.) ranks fourth in term of worldwide fruit production, and has economical and nutritional key values. The Cavendish cultivars correspond to more than 90% of the production of dessert banana while cooking cultivars are widely consumed locally around the banana belt production area. Many plants, if not all, produce Volatile Organic Compounds (VOCs) as a means of communication with their environment. Although flower and fruit VOCs have been studied for banana, the VOCs produced by the plant have never been identified despite their importance in plant health and development. A volatile collection methodology was optimized to improve the sensitivity and reproducibility of VOCs analysis from banana plants. We have identified 11 VOCs for the Cavendish, mainly (E,E)-α-farnesene (87.90 ± 11.28 ng/μl), methyl salicylate (33.82 ± 14.29) and 6-methyl-5-hepten-2-one (29.60 ± 11.66), and 14 VOCs for the Pacific Plantain cultivar, mainly (Z,E)-α-farnesene (799.64 ± 503.15), (E,E)-α-farnesene (571.24 ± 381.70) and (E) β ocimene (241.76 ± 158.49). This exploratory study paves the way for an in-depth characterisation of VOCs emitted by Musa plants.

  9. Leaf level emissions of volatile organic compounds (VOC) from some Amazonian and Mediterranean plants

    NASA Astrophysics Data System (ADS)

    Bracho-Nunez, A.; Knothe, N. M.; Welter, S.; Staudt, M.; Costa, W. R.; Liberato, M. A. R.; Piedade, M. T. F.; Kesselmeier, J.

    2012-11-01

    As volatile organic compounds (VOCs) significantly affect atmospheric chemistry (oxidative capacity) and physics (secondary organic aerosol formation and effects), emission inventories defining regional and global biogenic VOC emission strengths are important. The aim of this work was to achieve a description of VOC emissions from poorly described tropical vegetation to be compared with the quite well investigated and highly heterogeneous emissions from Mediterranean vegetation. For this task, common plant species of both ecosystems were investigated. Sixteen plant species from the Mediterranean area, which is known for its special diversity in VOC emitting plant species, were chosen. In contrast, little information is currently available regarding emissions of VOCs from tropical tree species at the leaf level. Twelve plant species from different environments of the Amazon basin, i.e. Terra firme, Várzea and Igapó, were screened for emission of VOCs at leaf level with a branch enclosure system. Analysis of the volatile organics was performed online by a proton-transfer-reaction mass spectrometer (PTR-MS) and offline by collection on adsorbent tubes and subsequent gas chromatographic analysis. Isoprene was quantitatively the most dominant compound emitted followed by monoterpenes, methanol and acetone. Most of the Mediterranean species emitted a variety of monoterpenes, whereas only five tropical species were monoterpene emitters exhibiting a quite conservative emission pattern (α-pinene > limonene > sabinene > β-pinene). Mediterranean plants showed additional emissions of sesquiterpenes, whereas in the case of plants from the Amazon region no sesquiterpenes were detected probably due to a lack of sensitivity in the measuring systems. On the other hand methanol emissions, an indicator of growth, were common in most of the tropical and Mediterranean species. A few species from both ecosystems showed acetone emissions. The observed heterogeneous emissions

  10. Real-time and online screening method for materials emitting volatile organic compounds

    NASA Astrophysics Data System (ADS)

    Kim, Changhyuk; Sul, Yong Tae; Pui, David Y. H.

    2016-09-01

    In the semiconductor industry, volatile organic compounds (VOCs) in the cleanroom air work as airborne molecular contamination, which reduce the production yield of semiconductor chips by forming nanoparticles and haze on silicon wafers and photomasks under ultraviolet irradiation during photolithography processes. Even though VOCs in outdoor air are removed by gas filters, VOCs can be emitted from many kinds of materials used in cleanrooms, such as organic solvents and construction materials (e.g., adhesives, flame retardants and sealants), threatening the production of semiconductors. Therefore, finding new replacements that emit lower VOCs is now essential in the semiconductor industry. In this study, we developed a real-time and online method to screen materials for developing the replacements by converting VOCs into nanoparticles under soft X-ray irradiation. This screening method was applied to measure VOCs emitted from different kinds of organic solvents and adhesives. Our results showed good repeatability and high sensitivity for VOCs, which come from aromatic compounds, some alcohols and all tested adhesives (Super glue and cleanroom-use adhesives). In addition, the overall trend of measured VOCs from cleanroom-use adhesives was well matched with those measured by a commercial thermal desorption-gas chromatography-mass spectrometry, which is a widely used off-line method for analyzing VOCs. Based on the results, this screening method can help accelerate the developing process for reducing VOCs in cleanrooms.

  11. Emission of volatile organic compounds (VOC) from tropical plant species in India.

    PubMed

    Padhy, P K; Varshney, C K

    2005-06-01

    Foliar emission of volatile organic compounds (VOC) from common Indian plant species was measured. Dynamic flow enclosure technique was used and the gas samples were collected onto Tenax-GC/Carboseive cartridges. The Tenax-GC/Carboseive cartridges were attached to the thermal disorber sample injection system and the gas sample was analysed using gas chromatography (GC) with flame ionisation detection (FID). Fifty-one local plant species were screened, out of which 36 species were found to emit VOC (4 high emitter; 28 moderate emitter; and 4 low-emitter), while in the remaining 15 species no VOC emission was detected or the levels of emission were below detection limit (BDL). VOC emission was found to vary from one species to another. There was a marked seasonal and diurnal variation in VOC emission. The minimum and maximum VOC emission values were < 0.1 and 87 microgg(-1) dry leaf h(-1) in Ficus infectoria and Lantana camara respectively. Out of the 51 plant species studied, 13 species are reported here for the first time. Among the nine tree species (which were selected for detailed study), the highest average hourly emission (9.69+/-8.39 microgg(-1) dry leaf) was observed in Eucalyptus species and the minimum in Syzygium jambolanum (1.89+/-2.48 microgg(-1) dry leaf). An attempt has been made to compare VOC emission from different plant species between present study and the literature (tropical and other regions).

  12. Assessment of Volatile Organic Compounds (VOCs) in indooor parking facilities at Houston, Texas

    NASA Astrophysics Data System (ADS)

    Kristanto, Gabriel Andari

    This dissertation identified the types, magnitudes, sources, and assessed risk exposure of VOCs in different types of indoor parking facilities. VOCs are ones of major pollutants emitted from automobiles. The indoor parking facilities included were attached garages, grounds, and underground parking. Modification of method TO15 by EPA had been applied for identifying types and magnitudes of VOCs. Results of these identifications are presented. Eight most abundant VOCs could be identified in every sampling location with toluene as the most abundant compound followed by m,p-xylene, ethylbenzene and benzene. Compare to ground and underground parking, attached garages have the highest concentration of TVOCs. For sources identification, BTEX, m,p-xylene and benzene, and toluene and benzene ratios are calculated. BTEX ratios for ground and underground parking are similar compare to attached garage due to the similar pattern of driving speed and the content of gasoline fuel. On the other hand the ratios of m,p-xylene and benzene and toluene and benzene in attached garage are higher compare to the same ratios for ground and underground parking due to other significant contributor of VOCs such as solvent, household cleanings stored. Cancer and noncancer risk assessment were also calculated. Results showed that cancer and noncancer risk due human exposures to VOC in indoor parking facilities were relatively low. However the risk of the human exposure to VOCs from indoor parking facilities has to be considered as a part of total risks of VOC exposures on human during their daily activities. When people in Houston have already exposed to high VOC concentrations from outdoor environment activities such as traffic and refineries and petrochemical facilities, additional activities causing VOC exposures will add the risk significantly.

  13. CHARACTERIZATION OF LOW-VOC LATEX PAINTS: VOLATILE ORGANIC COMPOUND CONTENT, VOC AND ALDEHYDE EMISSIONS, AND PAINT PERFORMANCE

    EPA Science Inventory

    The report gives results of laboratory tests to evaluate commercially available latex paints advertised as "low-odor," "low-VOC (volatile organic compound)," or "no-VOC." Measurements were performed to quantify the total content of VOCs in the paints...

  14. CHARACTERIZATION OF LOW-VOC LATEX PAINTS: VOLATILE ORGANIC COMPOUND CONTENT, VOC AND ALDEHYDE EMISSIONS, AND PAINT PERFORMANCE

    EPA Science Inventory

    The report gives results of laboratory tests to evaluate commercially available latex paints advertised as "low-odor," "low-VOC (volatile organic compound)," or "no-VOC." Measurements were performed to quantify the total content of VOCs in the paints...

  15. Vehicular emission of volatile organic compounds (VOCs) from a tunnel study in Hong Kong

    NASA Astrophysics Data System (ADS)

    Ho, K. F.; Lee, S. C.; Ho, W. K.; Blake, D. R.; Cheng, Y.; Li, Y. S.; Fung, K.; Louie, P. K. K.; Park, D.

    2009-06-01

    Vehicle emissions of VOCs were determined in summer and winter of 2003 at the Shing Mun Tunnel, Hong Kong. One hundred and ten VOCs were quantified in this study. The average concentration of the total measured VOCs at the inlet and outlet of the tunnel were 81 250 pptv and 117 850 pptv, respectively. Among the 110 compounds analyzed, ethene, ethyne and toluene were the most abundant species in the tunnel. The total measured VOC emission factors ranged from 67 mg veh-1 km-1 to 148 mg veh-1 km-1, with an average of 115 mg veh-1 km-1. The five most abundant VOCs observed in the tunnel were, in decreasing order, ethene, toluene, n-butane, propane and i-pentane. These five most abundant species contributed over 38% of the total measured VOCs emitted. The high propane and n-butane emissions were found to be associated with LPG-fueled taxi. And fair correlations were observed between marker species (ethene, i-pentane, n-nonane, BTEX) with fractions of gasoline-fueled or diesel-fueled vehicles. Moreover, ethene, ethyne, and propene are the key species that were abundant in the tunnel but not in gasoline vapors or LPG. In order to evaluate the ozone formation potential emissions in Hong Kong, the maximum increment reactivity is calculated. It was found that about 568 mg of O3 is induced by per vehicle per kilometer traveled. Among them, ethene, propene and toluene contribute most to the ozone-formation reactivity.

  16. [Estimation and forecast of volatile organic compounds emitted from paint uses in China].

    PubMed

    Wei, Wei; Wang, Shu-xiao; Hao, Ji-ming

    2009-10-15

    Based on the current consumptions and forecast consumptions of paints in China, using the volatile organic compounds (VOC) contents of paints calculated as emission factors, an emission inventory model was established to calculate provincial, sector-specific, and species-specific VOC emissions during 2005-2020. The results indicated that the VOC amount emitted from paint use was 1883 kt in 2005, of which aromatics, alcohol compounds, ester compounds, ether compounds and ketone compounds were the main species. The maximum incremental reactivity (MIR,O3/VOC) of VOC emitted in 2005 was about 3.6 g/kg, and the toxic VOC accounted for 31% of the total in weight. The VOC emissions would increase to 5673 kt in 2020 if there were no further control policies and actions taken. Therefore, it is essential to implement the VOC emission control from paint uses as soon as possible. Two control scenarios were developed to evaluate the potential of VOC emission reductions. In 2020, VOC emissions from paint uses might be controlled at 3 519 kt through the improvement of paints quality to the level of that in developed countries in 1990s and installation of waste gas treatment equipments in newly-built factories. VOC emissions could be further reduced to 2243 kt if the quality of decorative paint and wood paint would be improved to the current level of that in developed countries and all factories install waste gas treatment equipments. All these control measures also helpe to reduce the toxicity and atmospheric oxidation reactivity of VOC emissions.

  17. Real time analysis of volatile organic compounds (VOCs) in centenarians.

    PubMed

    Mazzatenta, Andrea; Pokorski, Mieczyslaw; Di Giulio, Camillo

    2015-04-01

    Centenarians are a model to study human longevity and the physiological process of aging. A plethora of studies on this model show the complexity of the system. Laboratory studies fail to find a biomarker of senescence. The real time exhaled breath volatile organic compounds (VOCs) has been suggested as a new biomarker to detect and monitor physiological processes in the respiratory system. VOCs exhaled by centenarians have not been studied in the general population and across-age-groups. In the present study we investigated, in real time, the breath properties and VOC exhaled content in healthy centenarians as compared with non-centenarian seniors and young healthy subjects. We found distinctly different breath pattern and distribution profiles of VOCs in the centenarians. Thus, the VOCs measurement allowed to discriminate the differences between the age-groups. We propose a VOCs fingerprint as a biomarker underlying the physiological mechanisms of aging and longevity. Longevity should be considered physiologically as a new phase of life, characteristic of the well adapted subject. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Novel collection method for volatile organic compounds (VOCs) from dogs.

    PubMed

    Holderman, Chris J; Kaufman, Phillip E; Booth, Matthew M; Bernier, Ulrich R

    2017-09-01

    Host derived chemical cues are an important aspect of arthropod attraction to potential hosts. Host cues that act over longer distances include CO2, heat, and water vapor, while cues such as volatile organic compounds (VOCs) act over closer distances. Domestic dogs are important hosts for disease cycles that include dog heartworm disease vectored by mosquitoes, however the host VOCs utilized by vectors are not well known. Herein we present a novel method that sampled VOCs from a dog host. A Tenax TD stainless steel tube was held near a dog's fur and skin, which collected VOCs that were later desorbed and tentatively identified using a gas chromatograph-mass spectrospectrometer (GC-MS). Background air chemicals were subtracted from the dog sample, resulting in 182 differentiated compounds, a majority of which were identified by ionization fragmentation patterns. Four dogs were sampled and shared 41 of the identified chemicals. VOCs were representative of aliphatics, aromatics, aldehydes, alcohols and carboxylic acids. This chemical characterization method has the potential to identify both individuals and breeds of dogs in addition to other potential uses such as disease diagnosis. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Vehicular emission of volatile organic compounds (VOCs) from a tunnel study in Hong Kong

    NASA Astrophysics Data System (ADS)

    Ho, K. F.; Lee, S. C.; Ho, W. K.; Blake, D. R.; Cheng, Y.; Li, Y. S.; Ho, S. S. H.; Fung, K.; Louie, P. K. K.; Park, D.

    2009-10-01

    Vehicle emissions of volatile organic compounds (VOCs) were determined at the Shing Mun Tunnel, Hong Kong in summer and winter of 2003. One hundred and ten VOCs were quantified in this study. The average concentration of the total measured VOCs at the inlet and outlet of the tunnel were 81 250 pptv and 117 850 pptv, respectively. Among the 110 compounds, ethene, ethyne and toluene were the most abundant species in the tunnel. The total measured VOC emission factors ranged from 67 mg veh-1 km-1 to 148 mg veh-1 km-1, with an average of 115 mg veh-1 km-1. The five most abundant VOCs observed in the tunnel were, in decreasing order, ethene, toluene, n-butane, propane and i-pentane. These five most abundant species contributed over 38% of the total measured VOCs emitted. The high propane and n-butane emissions were found to be associated with liquefied petroleum gas (LPG)-fueled taxis. Fair correlations were observed between marker species (ethene, i-pentane, n-nonane, and benzene, toluene, ethylbenzene and xylenes - BTEX) with fractions of gasoline-fueled or diesel-fueled vehicles. Moreover, ethene, ethyne, and propene are the key species that were abundant in the tunnel but not in gasoline vapors or LPG. The ozone formation potential from the VOCs in Hong Kong was evaluated by the maximum increment reactivity (MIR). It was found to be 568 mg of ozone per vehicle per kilometer traveled. Among them, ethene, propene and toluene contribute most to the ozone-formation reactivity.

  20. Novel collection method for volatile organic compounds (VOCs) from dogs

    USDA-ARS?s Scientific Manuscript database

    Host derived chemical cues are an important aspect of arthropod attraction to potential hosts. Host cues that act over longer distances include CO2, heat, and water vapor, while cues such as volatile organic compounds (VOCs) act over closer distances. Domestic dogs are important hosts for disease cy...

  1. Leaf level emissions of volatile organic compounds (VOC) from some Amazonian and Mediterranean plants

    NASA Astrophysics Data System (ADS)

    Bracho-Nunez, A.; Knothe, , N. M.; Welter, S.; Staudt, M.; Costa, W. R.; Liberato, M. A. R.; Piedade, M. T. F.; Kesselmeier, J.

    2013-09-01

    Emission inventories defining regional and global biogenic volatile organic compounds (VOC) emission strengths are needed to determine the impact of VOC on atmospheric chemistry (oxidative capacity) and physics (secondary organic aerosol formation and effects). The aim of this work was to contribute with measurements of tree species from the poorly described tropical vegetation in direct comparison with the quite well-investigated, highly heterogeneous emissions from Mediterranean vegetation. VOC emission from sixteen plant species from the Mediterranean area were compared with twelve plant species from different environments of the Amazon basin by an emission screening at leaf level using branch enclosures. Analysis of the volatile organics was performed online by a proton-transfer-reaction mass spectrometer (PTR-MS) and offline by collection on adsorbent tubes and subsequent gas chromatographic analysis. Isoprene was the most dominant compound emitted followed by monoterpenes, methanol and acetone. The average loss rates of VOC carbon in relation to the net CO2 assimilation were found below 4% and indicating normal unstressed plant behavior. Most of the Mediterranean species emitted a large variety of monoterpenes, whereas only five tropical species were identified as monoterpene emitters exhibiting a quite conservative emission pattern (α-pinene < limonene < sabinene < ß-pinene). Mediterranean plants showed additional emissions of sesquiterpenes. In the case of Amazonian plants no sesquiterpenes were detected. However, missing of sesquiterpenes may also be due to a lack of sensitivity of the measuring systems. Furthermore, our screening activities cover only 1% of tree species of such tropical areas as estimated based on recent biodiversity reports. Methanol emissions, an indicator of growth, were found to be common in most of the tropical and Mediterranean species. A few species from both ecosystems showed acetone emissions. The observed heterogeneous

  2. Biofiltration for control of volatile organic compounds (VOCS)

    SciTech Connect

    Bishop, D.F.; Govind, R.

    1995-10-01

    Air biofiltration is a promising technology for control of air emissions of biodegradable volatile organic compounds (VOCs). In conjunction with vacuum extraction of soils or air stripping of ground water, it can be used to mineralize VOCs removed from contaminated soil or groundwater. The literature describes three major biological systems for treating contaminated air bioscrubbers, biotrickling filters and biofilters. Filter media can be classified as: bioactive fine or irregular particulates, such as soil, peat, compost or mixtures of these materials; pelletized, which are randomly packed in a bed; and structured, such as monoliths with defined or variable passage size and geometry. The media can be made of sorbing and non-absorbing materials. Non-bioactive pelletized and structured media require recycled solutions of nutrients and buffer for efficient microbial activity and are thus called biotrickling filters. Extensive work has been conducted to improve biofiltration by EPA`s Risk Reduction Engineering Laboratory and the University of Cincinnati in biofilters using pelletized and structured media and improved operational approaches. Representative VOCs in these studies included compounds with a range of aqueous solubilities and octanol-water partition coefficients. The compounds include iso-pentane, toluene, methylene chloride, trichloroethylene (TCE), ethyl benzene, chlorobenzene and perchloroethylene (PCE) and alpha ({alpha}-) pinene. Comparative studies were conducted with peat/compost biofilters using isopentane and {alpha}-pinene. Control studies were also conducted to investigate adsorption/desorption of contaminants on various media using mercuric chloride solution to insure the absence of bioactivity.

  3. Measurements of volatile organic compound (VOC) emissions from wood stains using an electronic balance

    SciTech Connect

    Zhang, J.S.; Nong, G.; Shaw, C.Y.; Wang, J.

    1999-07-01

    An emissions test method using an electronic balance is introduced for measuring the TVOC emission rates of oil-based wood stains, with a detailed procedure for preparing test specimens. The emission characteristics of volatile organic compounds (VOC) from an artificial wood stain and an oil-based commercial wood stain were determined. Results showed that VOC emissions from both stains included a surface evaporation and an internal diffusion sub-process. With regard to time, the entire emission period could be divided into three periods: (1) an initial evaporation-controlled period that was characterized by a high and fast decaying emission rate, (2) a transition period (following the initial period) in which the emissions transited from an evaporation-controlled to an internal diffusion-controlled process, and (3) an internal diffusion-controlled period that was characterized by a low and slowly decaying emission rate. For the commercial wood stain tested, the length of the initial period was approximately three hours, and about 46% of the emittable VOC mass was emitted during this short period. The transition period was between 3 and 6.5 hours from the start of testing and only accounted for about 4% of VOC mass emitted. The rest (about 50%) of the VOC mass was emitted in the diffusion-controlled period over a long period of time. Comparison between the commercial wood stain and an artificial wood stain suggested that the pigments/solids in the wood stain had significant effect on the time scales and amount of mass emitted during each emission period. The presence of additional VOCs in the commercial wood stain might have also affected the emission profiles. These results are useful for developing better models for predicting the emission rates. The electronic balance method was also compared with those determined from the TVOC concentrations measured at the chamber exhaust (referred to as chamber method). Results show that the two methods agreed well with each

  4. [Volatile Organic Compounds (VOC): definition, classification and properties].

    PubMed

    Cicolella, A

    2008-02-01

    The term volatile organic compounds includes a wide variety of chemical substances with the common feature of being carbon compounds that are volatile at ambient temperature. They can be classified into different families defined by their chemical formulae, each of which possesses common properties, although there may be major differences in terms of toxicity. For that reason the effects of VOC on health have to be considered both in an individual way and also from a global viewpoint on account of their common toxic properties and the role they play in the formation of environmental photo-oxidative pollutants, both outdoors and indoors.

  5. Rapid leaf development drives the seasonal pattern of volatile organic compound (VOC) fluxes in a 'coppiced' bioenergy poplar plantation.

    PubMed

    Brilli, Federico; Gioli, Beniamino; Fares, Silvano; Terenzio, Zenone; Zona, Donatella; Gielen, Bert; Loreto, Francesco; Janssens, Ivan A; Ceulemans, Reinhart

    2016-03-01

    Leaves of fast-growing, woody bioenergy crops often emit volatile organic compounds (VOC). Some reactive VOC (especially isoprene) play a key role in climate forcing and may negatively affect local air quality. We monitored the seasonal exchange of VOC using the eddy covariance technique in a 'coppiced' poplar plantation. The complex interactions of VOC fluxes with climatic and physiological variables were also explored by using an artificial neural network (Self Organizing Map). Isoprene and methanol were the most abundant VOC emitted by the plantation. Rapid development of the canopy (and thus of the leaf area index, LAI) was associated with high methanol emissions and high rates of gross primary production (GPP) since the beginning of the growing season, while the onset of isoprene emission was delayed. The highest emissions of isoprene, and of isoprene photo-oxidation products (Methyl Vinyl Ketone and Methacrolein, iox ), occurred on the hottest and sunniest days, when GPP and evapotranspiration were highest, and formaldehyde was significantly deposited. Canopy senescence enhanced the exchange of oxygenated VOC. The accuracy of methanol and isoprene emission simulations with the Model of Emissions of Gases and Aerosols from Nature increased by applying a function to modify their basal emission factors, accounting for seasonality of GPP or LAI.

  6. Emission and Photochemical Evolution of Low Vapor Pressure-Volatile Organic Compounds (LVP-VOCs): from Consumer Products to Secondary Organic Aerosol

    NASA Astrophysics Data System (ADS)

    Li, L.; Kacarab, M.; Chen, C. L.; Price, D.; Carter, W. P. L.; Cocker, D. R., III

    2015-12-01

    Missing emission sources contribute to potential problems in air quality modeling and human health. Low Vapor Pressure-Volatile Organic Compounds (LVP-VOCs) are widely used in consumer products and currently receive VOC exemptions based on their vapor pressure. However, 58.5 TPD LVP-VOC is estimated to emit in 2020 from consumer products in California based on government and industry inventory data. This work investigates the emission and photochemical evolution of major LVP-VOCs in consumer products to demonstrate LVP-VOC impacts on criteria air pollutants. LVP-VOC emission potential is investigated by offline gravimetric and online headspace tracking pure compounds and consumer product mixtures under ambient relevant conditions. Only 3 of the 14 pure LVP-VOCs were found to be atmospherically unavailable. All target LVP-VOCs are observed to evaporate from tested consumer product mixtures. We found improved thermodynamic parameters to predict LVP-VOC evaporation rate. LVP-VOCs photochemical evolution and their impact on ozone and secondary organic aerosol (SOA) formation are evaluated by integrating SAPRC-11 modeling with laboratory studies in a 90 m3 dual environmental chamber at UC Riverside/CE-CERT. Simultaneous photooxidation experiments, with and without the LVP-VOC, are conducted in the presence of reactive organic gas (ROG) surrogate representing urban chemical smog. Further, LVP-VOC photochemical evolution pathway is investigated under various atmospheric activity (LVP + H2O2, LVP+NO or LVP+H2O2+NO) in the environmental chamber. Gas phase and particle phase mass spectrometers (SIFT-MS, Selected Ion Flow Tube-Mass Spectrum and HR-ToF-MS, High Resolution Time-of-Flight Aerosol mass Spectrometer) are applied to monitor the evolution of LVP-VOCs in the controlled atmosphere. The potential of LVP-VOC oxidation into ELVOC is also illustrated. We finally interpret the health risk and environmental concern related to LVP-VOC emission and photoxidation.

  7. Emissions of Volatile Organic Compounds (VOCs) from Animal Husbandry: Chemical Compositions, Separation of Sources and Animal Types

    NASA Astrophysics Data System (ADS)

    Yuan, B.; Coggon, M.; Koss, A.; Warneke, C.; Eilerman, S. J.; Neuman, J. A.; Peischl, J.; Aikin, K. C.; Ryerson, T. B.; De Gouw, J. A.

    2016-12-01

    Concentrated animal feeding operations (CAFOs) are important sources of volatile organic compounds (VOCs) in the atmosphere. We used a hydronium ion time-of-flight chemical ionization mass spectrometer (H3O+ ToF-CIMS) to measure VOC emissions from CAFOs in the Northern Front Range of Colorado during an aircraft campaign (SONGNEX) for regional contributions and from a mobile laboratory sampling for chemical characterizations of individual animal feedlots. The main VOCs emitted from CAFOs include carboxylic acids, alcohols, carbonyls, phenolic species, sulfur- and nitrogen-containing species. Alcohols and carboxylic acids dominate VOC concentrations. Sulfur-containing and phenolic species become more important in terms of odor activity values and NO3 reactivity, respectively. The high time-resolution mobile measurements allow the separation of the sources of VOCs from different parts of the operations occurring within the facilities. We show that the increase of ethanol concentrations were primarily associated with feed storage and handling. We apply a multivariate regression analysis using NH3 and ethanol as tracers to attribute the relative importance of animal-related emissions (animal exhalation and waste) and feed-related emissions (feed storage and handling) for different VOC species. Feed storage and handling contribute significantly to emissions of alcohols, carbonyls and carboxylic acids. Phenolic species and nitrogen-containing species are predominantly associated with animals and their waste. VOC ratios can be potentially used as indicators for the separation of emissions from dairy and beef cattle from the regional aircraft measurements.

  8. Effect of a fungal infection on the profile of volatile organic compounds emitted by plant roots.

    PubMed

    Fiers, M; Lognay, G; Wathelet, J P; Fauconnier, M L; Jijakli, M H

    2012-01-01

    It is known since few years that the aerial and underground parts of the plants emit volatile organic compounds (VOCs) that can interact with other organisms of the environment. They are involved in the attraction of seed dispersers and pollinators, the repellence of enemies via direct or indirect mechanisms and the induction of defence systems in other parts of the same plant or in other plants in the vicinity (Dudareva et al., 2006). It has been shown previously that the VOCs spectrum emitted by plants hardly depends on their physiological state (Kant et al., 2009). However those phenomenons were poorly studied at the edaphic level. Thus, the Rhizovol project, a multidisciplinary project in Gembloux Agro-Bio Tech was set up to study the emissions of VOCs by plant roots and their interactions with other organisms of the rhizosphere. As a partner of this project, the Plant Pathology Unit of Gembloux Agro-Bio Tech chose to study the effect of a fungal infection on the profile of VOCs emitted by plant roots, based on three model organisms, barley (Hordeum vulgare L.), since it is a major crop in Belgium that can suffer a large range of aggressions, and two pathogenic fungi, Cochliobolus sativus and Fusarium culmorum, responsible for root and foot rots and seedling blight on cereals (Wiese, 1977). Later in the development, C. sativus produces elongate brown-black lesions (spot blotch) and F. culmorum induces head blight and produces mycotoxins that make the grain unsuitable for consumption (Nielsen et al., 2011). The objective of this work was to identify the VOCs emitted during the dual interactions between barley roots and a pathogenic fungus. The study was performed in two steps; first, the independent analyses of the VOCs emitted by each of the partners (C. sativus, F. culmorum and healthy barley roots), then the analyses of the VOCs spectrum emitted during dual interactions.

  9. Attraction of the gypsy moth to volatile organic compounds (VOCs) of damaged Dahurian larch.

    PubMed

    Li, Jing; Valimaki, Sanna; Shi, Juan; Zong, Shixiang; Luo, Youqing; Heliovaara, Kari

    2012-01-01

    Olfactory responses of the gypsy moth Lymantria dispar (L.) (Lepidoptera: Lymantriidae), a major defoliator of deciduous trees, were examined in Inner Mongolia, China. We studied whether the gypsy moth adults are attracted by the major volatile organic compounds (VOCs) of damaged Larix gmelinii (Dahurian larch) foliage and compared the attractiveness of the plant volatiles with that of the synthetic sex pheromone. Our results indicated that the VOCs of the Dahurian larch were effective in attracting gypsy moth males especially during the peak flight period. The VOCs also attracted moths significantly better than the sex pheromone of the moth. Our study is the first trial to show the responses of adult gypsy moths to volatile compounds emitted from a host plant. Electroantennogram responses of L. gmelinii volatiles on gypsy moths supported our field observations. A synergistic effect between host plant volatiles and sex pheromone was also obvious, and both can be jointly applied as a new attractant method or population management strategy of the gypsy moth.

  10. Compositions of volatile organic compounds emitted from melted virgin and waste plastic pellets.

    PubMed

    Yamashita, Kyoko; Yamamoto, Naomichi; Mizukoshi, Atsushi; Noguchi, Miyuki; Ni, Yueyong; Yanagisawa, Yukio

    2009-03-01

    To characterize potential air pollution issues related to recycling facilities of waste plastics, volatile organic compounds (VOCs) emitted from melted virgin and waste plastics pellets were analyzed. In this study, laboratory experiments were performed to melt virgin and waste plastic pellets under various temperatures (150, 200, and 250 degrees C) and atmospheres (air and nitrogen [N2]). In the study presented here, low-density polyethylene (LDPE), polypropylene (PP), polystyrene (PS) and the recycled waste plastic pellets were used. The VOCs generated from each plastic pellets were collected by Tenax/Carboxen adsorbent tubes and analyzed by thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS). The result showed the higher temperatures generated larger amounts of total VOCs (TVOCs). The VOCs emitted from the virgin plastic pellets likely originated from polymer degradation. Smaller TVOC emissions were observed in N2 atmosphere than in air atmosphere. In particular, larger amounts of the oxygenated compounds, which are generally hazardous and malodorous, were detected in air than in N2. In addition to the compounds originating from polymer degradation, the compounds originating from the plastic additives were also detected from LDPE and PS. Furthermore, various species of VOCs likely originating from contaminant inseparate polyvinyl chloride (PVC), food residues, cleaning agents, degreasers, and so on were detected from the waste plastic. Thus, melting waste plastics, as is conducted in recycling facilities, might generate larger amounts of potentially toxic compounds than producing virgin plastics.

  11. Measurements of Volatile Organic Compounds (VOCs) on Board of the Zeppelin NT during the PEGASOS Campaign in 2012

    NASA Astrophysics Data System (ADS)

    Jäger, Julia; Hofzumahaus, Andreas; Beck, Harry; Rohrer, Franz; Broch, Sebastian; Fuchs, Hendrik; Gomm, Sebastian; Holland, Frank; Lu, Keding; Kiendler-Scharr, Astrid; Mentel, Thomas; Rose, Bernhard; Wegener, Robert; Wahner, Andreas

    2013-04-01

    Volatile Organic Compounds (VOCs) are mostly emitted at the ground and are degraded by the reactions with OH, NO3 or O3 as they rise upwards in the atmosphere. VOCs play an important role as sources and sinks for radicals in the troposphere. Up to date, most of the VOC measurements were performed from ground based platforms; the profile measurements across the whole planetary boundary layer (PBL) are still quite limited which restrained the exploring of the VOCs chemistry of the entire PBL. This although these measurements are particularly interesting, as most of the chemistry of the VOC degradation in the troposphere takes place in the PBL. Moreover, fast VOCs measurements utilizing Gas Chromatography coupled with Mass Spectrometry (GC-MS) are a challenge due to the great chemical variability of VOC species. Therefore accurate in-situ measurements of VOCs together with other species as CO, NOx, O3 and the OH reactivity, encompassing different levels of altitude and fast time resolution, would essentially improve the understanding of the VOC distribution in the lower troposphere. Here we present the setup and the modifications of the fast GC-MS system and the results of the PEGASOS Zeppelin campaigns in summer 2012. First, we present our developments and modifications of an in-flight GC-MS system to detect volatile non methane hydrocarbons (NMHC) with a time resolution of 3 minutes and a detection limit in the order of 2 pptv. The modified setup enabled us to analyze 70 different VOC species, ranging from alkanes (C4 to C11), aromatics and terpenes to oxygenated hydrocarbons (OVOC) such as alcohols and aldehydes. Second, in contrast to previous airplane studies also utilizing a GC-MS system, the Zeppelin NT as a measuring platform during the PEGASOS campaign enabled us to measure vertical profiles up to 1500m at low travelling speeds which means a high spatial resolution. We will present results for selected VOC that offer new insights on height profiles

  12. Emissions of volatile organic compounds (VOCs) from concentrated animal feeding operations (CAFOs): chemical compositions and separation of sources

    NASA Astrophysics Data System (ADS)

    Yuan, Bin; Coggon, Matthew M.; Koss, Abigail R.; Warneke, Carsten; Eilerman, Scott; Peischl, Jeff; Aikin, Kenneth C.; Ryerson, Thomas B.; de Gouw, Joost A.

    2017-04-01

    Concentrated animal feeding operations (CAFOs) emit a large number of volatile organic compounds (VOCs) to the atmosphere. In this study, we conducted mobile laboratory measurements of VOCs, methane (CH4) and ammonia (NH3) downwind of dairy cattle, beef cattle, sheep and chicken CAFO facilities in northeastern Colorado using a hydronium ion time-of-flight chemical-ionization mass spectrometer (H3O+ ToF-CIMS), which can detect numerous VOCs. Regional measurements of CAFO emissions in northeastern Colorado were also performed using the NOAA WP-3D aircraft during the Shale Oil and Natural Gas Nexus (SONGNEX) campaign. Alcohols and carboxylic acids dominate VOC concentrations and the reactivity of the VOCs with hydroxyl (OH) radicals. Sulfur-containing and phenolic species provide the largest contributions to the odor activity values and the nitrate radical (NO3) reactivity of VOC emissions, respectively. VOC compositions determined from mobile laboratory and aircraft measurements generally agree well with each other. The high time-resolution mobile measurements allow for the separation of the sources of VOCs from different parts of the operations occurring within the facilities. We show that the emissions of ethanol are primarily associated with feed storage and handling. Based on mobile laboratory measurements, we apply a multivariate regression analysis using NH3 and ethanol as tracers to determine the relative importance of animal-related emissions (animal exhalation and waste) and feed-related emissions (feed storage and handling) for different VOC species. Feed storage and handling contribute significantly to emissions of alcohols, carbonyls, carboxylic acids and sulfur-containing species. Emissions of phenolic species and nitrogen-containing species are predominantly associated with animals and their waste.

  13. Removal of volatile organic compounds (VOCs) using biofilters

    SciTech Connect

    Carriere, P.E.; Mohaghegh, S.D.; Madabhushi, B.S.

    1995-12-31

    One of the most significant air pollution control challenges being faced by the Federal and State agencies and the chemical process industries is the control of emissions of volatile organic compounds (VOCs). VOCs are discharged from process industries as major components of mixed organic wastes which contaminate the environment. Among these wastes, benzene, toluene, ethyl benzene and xylene are classified as major pollutants with high frequencies of occurrence on the EPA list of priority pollutants. Biofiltration, a recent air pollution control technology, is the removal and decomposition of contaminants present in emissions of non hazardous substances using a biologically activated medium. Biofiltration involves contacting the contaminated emission gas stream with microorganisms in a filter media. Biofiltration utilizes microorganisms immobilized in the form of a biofilm layer on an adsorptive filter media. Compared to other technologies, biofiltration is inexpensive, reliable and requires no post treatment. The main objective of this study was to compare the performance of both Granular Activated Carbon (GAC) and Biologically Activated Carbon (BAC) for the removal of benzene and toluene.

  14. LakeVOC; A Deterministic Model to Estimate Volatile Organic Compound Concentrations in Reservoirs and Lakes

    USGS Publications Warehouse

    Bender, David A.; Asher, William E.; Zogorski, John S.

    2003-01-01

    This report documents LakeVOC, a model to estimate volatile organic compound (VOC) concentrations in lakes and reservoirs. LakeVOC represents the lake or reservoir as a two-layer system and estimates VOC concentrations in both the epilimnion and hypolimnion. The air-water flux of a VOC is characterized in LakeVOC in terms of the two-film model of air-water exchange. LakeVOC solves the system of coupled differential equations for the VOC concentration in the epilimnion, the VOC concentration in the hypolimnion, the total mass of the VOC in the lake, the volume of the epilimnion, and the volume of the hypolimnion. A series of nine simulations were conducted to verify LakeVOC representation of mixing, dilution, and gas exchange characteristics in a hypothetical lake, and two additional estimates of lake volume and MTBE concentrations were done in an actual reservoir under environmental conditions. These 11 simulations showed that LakeVOC correctly handled mixing, dilution, and gas exchange. The model also adequately estimated VOC concentrations within the epilimnion in an actual reservoir with daily input parameters. As the parameter-input time scale increased (from daily to weekly to monthly, for example), the differences between the measured-averaged concentrations and the model-estimated concentrations generally increased, especially for the hypolimnion. This may be because as the time scale is increased from daily to weekly to monthly, the averaging of model inputs may cause a loss of detail in the model estimates.

  15. Measurements of chlorinated volatile organic compounds emitted from office printers and photocopiers.

    PubMed

    Kowalska, Joanna; Szewczyńska, Małgorzata; Pośniak, Małgorzata

    2015-04-01

    Office devices can release volatile organic compounds (VOCs) partly generated by toners and inks, as well as particles of paper. The aim of the presented study is to identify indoor emissions of volatile halogenated organic compounds into the office workspace environment. Mixtures of organic pollutants emitted by seven office devices, i.e. printers and copiers, were analyzed by taking samples in laboratory conditions during the operation of these appliances. Tests of volatile organic compound emissions from selected office devices were conducted in a simulated environment (test chamber). Samples of VOCs were collected using three-layered thermal desorption tubes. Separation and identification of organic pollutant emissions were made using thermal desorption combined with gas chromatography coupled to mass spectrometry. Test chamber studies indicated that operation of the office printer and copier would contribute to the significant concentration level of VOCs in typical office indoor air. Among the determined volatile halogenated compounds, only chlorinated organic compounds were identified, inter alia: trichloroethylene - carcinogenic - and tetrachloroethylene - possibly carcinogenic to human. The results show that daily exposure of an office worker to chemical factors released by the tested printing and copying units can be variable in terms of concentrations of VOCs. The highest emissions in the test chamber during printing were measured for ethylbenzene up to 41.3 μg m(-3), xylenes up to 40.5 μg m(-3) and in case of halogenated compounds the highest concentration for chlorobenzene was 6.48 μg m(-3). The study included the comparison of chamber concentrations and unit-specific emission rates of selected VOCs and the identified halogenated compounds. The highest amount of total VOCs was emitted while copying with device D and was rated above 1235 μg m(-3) and 8400 μg unit(-1) h(-1) on average.

  16. Key volatile organic compounds emitted from swine nursery house

    NASA Astrophysics Data System (ADS)

    Yao, H. Q.; Choi, H. L.; Zhu, K.; Lee, J. H.

    2011-05-01

    This study was carried out to quantify the concentration and emission levels of key volatile organic compounds (VOCs) - sulfides, indolics, phenolics and volatile fatty acids (VFA) - emitted from swine nursery house, and assess the effect of microclimate (including temperature, relative humidity and air speed) on the key odorous compounds. Samples were collected from the Experimental Farm of Seoul National University in Suwon, South Korea. And the collection took place for four seasons and the sampling time was fixed at 10:30 in the morning. The application of one-way ANOVA and Bonferroni t analyses revealed that, most of the odorous compound concentrations, such as dimethyl sulfide (DMS), dimethyl disulfide (DMDS), indole, p-cresol and all the volatile fatty acids were lowest during the summer ( P < 0.01). Meanwhile, negative correlations were observed between temperature and odorants, as well as air speed and odorants. A possible reason was that high ventilation transferred most of the odors out of the house during the summer. From the whole year data, non-linear multiple regressions were conducted and the equations were proposed depending upon the relationships between microclimate parameters and odorous compounds. The equations were applied in hope of easily calculating the concentrations of the odorous compounds in the commercial farms. The results obtained in this study should be used for reducing the volatile organic compounds by controlling microclimate parameters and also could be helpful in setting a guideline for good management practices in nursery house.

  17. Characteristics of volatile organic compounds (VOCs) from the evaporative emissions of modern passenger cars

    NASA Astrophysics Data System (ADS)

    Yue, Tingting; Yue, Xin; Chai, Fahe; Hu, Jingnan; Lai, Yitu; He, Liqang; Zhu, Rencheng

    2017-02-01

    Volatile organic compounds (VOCs) from vehicle evaporative emissions contribute substantially to photochemical air pollution. Yet, few studies of the characteristics of VOCs emitted from vehicle evaporative emissions have been published. We investigate the characteristics of 57 VOCs in hot soak, 24 h diurnal and 48 h diurnal emissions by applying the Sealed Housing Evaporative Determination unit (SHED) test to three modern passenger cars (one US Tier 2 and two China IV vehicles) using two different types of gasoline. The characteristics of the VOCs from the hot soak, 24 h diurnal and 48 h diurnal emissions were different due to their different emission mechanisms. In the hot soak emissions, toluene, isopentane/n-pentane, and 2,2,4-trimethylpentane were dominant species. In the 24 h and 48 h diurnal emissions, isopentane and n-pentane were dominant species. Toluene was the third most dominant component in the 24 h diurnal emissions but decreased by a mass of 42%-80% in the 48 h diurnal emissions. In the hot soak, 24 h diurnal and 48 h diurnal emissions, alkanes were generally the dominant hydrocarbons, followed by aromatics and olefins. However, owing to different evaporative emission mechanisms, the weight percentages of the aromatic hydrocarbons decreased and the weight percentages of the alkanes increased from the hot soak test to the 24 h diurnal and 48 h diurnal tests for each vehicle. The dominant contributors to the ozone formation potentials (OFPs) were also different in the hot soak, 24 h diurnal and 48 h diurnal emissions. The OFPs (g O3/g VOC) of the hot soak emissions were higher than those of the 24 h and 48 h diurnal emissions. In addition, the combined effect of decreasing the olefin and aromatic contents of gasoline on vehicle evaporative emissions was investigated. The aromatics all decreased substantially in the hot soak, 24 h and 48 h diurnal emissions, and the total masses of the VOCs and OFPs decreased, with the greatest reduction occurring in

  18. Volatile organic compounds (VOCs) in surface coating materials: Their compositions and potential as an alternative fuel.

    PubMed

    Dinh, Trieu-Vuong; Choi, In-Young; Son, Youn-Suk; Song, Kyu-Yong; Sunwoo, Young; Kim, Jo-Chun

    2016-03-01

    A sampling system was designed to determine the composition ratios of VOCs emitted from 31 surface coating materials (SCMs). Representative architectural, automotive, and marine SCMs in Korea were investigated. Toluene, ethylbenzene, and xylene were the predominant VOCs. The VOC levels (wt%) from automotive SCMs were significantly higher than those from architectural and marine paints. It was found that target SCMs comprised mainly VOCs with 6-10 carbon atoms in molecules, which could be adsorbed by activated carbon. The saturated activated carbon which had already adsorbed toluene, ethylbenzene, and m-xylene was combusted. The saturated activated carbon was more combustible than new activated carbon because it comprised inflammable VOCs. Therefore, it could be an alternative fuel when using in a "fuelization system". To use the activated carbon as a fuel, a control technology of VOCs from a coating process was also designed and introduced.

  19. Pollution characteristics and health risk assessment of volatile organic compounds emitted from different plastic solid waste recycling workshops.

    PubMed

    He, Zhigui; Li, Guiying; Chen, Jiangyao; Huang, Yong; An, Taicheng; Zhang, Chaosheng

    2015-04-01

    The pollution profiles of volatile organic compounds (VOCs) emitted from different recycling workshops processing different types of plastic solid waste (PSW) and their health risks were investigated. A total of 64 VOCs including alkanes, alkenes, monoaromatics, oxygenated VOCs (OVOCs), chlorinated VOCs (ClVOCs) and acrylonitrile during the melting extrusion procedure were identified and quantified. The highest concentration of total VOCs (TVOC) occurred in the poly(acrylonitrile-butadiene styrene) (ABS) recycling workshop, followed by the polystyrene (PS), polypropylene (PP), polyamide (PA), polyvinyl chloride (PVC), polyethylene (PE) and polycarbonate (PC) workshops. Monoaromatics were found as the major component emitted from the ABS and PS recycling workshops, while alkanes were mainly emitted from the PE and PP recycling processes, and OVOCs from the PVC and PA recycling workshops. According to the occupational exposure limits' (OEL) assessment, the workers suffered acute and chronic health risks in the ABS and PS recycling workshops. Meanwhile, it was found that most VOCs in the indoor microenvironments were originated from the melting extrusion process, while the highest TVOC concentration was observed in the PS rather than in the ABS recycling workshop. Non-cancer hazard indices (HIs) of all individual VOCs were <1.0, whereas the total HI in the PS recycling workshop was 1.9, posing an adverse chronic health threat. Lifetime cancer risk assessment suggested that the residents also suffered from definite cancer risk in the PS, PA, ABS and PVC recycling workshops. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. 40 CFR 60.312 - Standard for volatile organic compounds (VOC).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for volatile organic compounds (VOC). 60.312 Section 60.312 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Surface Coating of Metal Furniture § 60.312 Standard for volatile organic compounds (VOC). (a) On...

  1. 40 CFR 60.312 - Standard for volatile organic compounds (VOC).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for volatile organic compounds (VOC). 60.312 Section 60.312 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Surface Coating of Metal Furniture § 60.312 Standard for volatile organic compounds (VOC). (a) On...

  2. 40 CFR 60.312 - Standard for volatile organic compounds (VOC).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for volatile organic compounds (VOC). 60.312 Section 60.312 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Surface Coating of Metal Furniture § 60.312 Standard for volatile organic compounds (VOC). (a) On...

  3. 40 CFR 60.312 - Standard for volatile organic compounds (VOC).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for volatile organic compounds (VOC). 60.312 Section 60.312 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Surface Coating of Metal Furniture § 60.312 Standard for volatile organic compounds (VOC). (a) On...

  4. 40 CFR 60.312 - Standard for volatile organic compounds (VOC).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for volatile organic compounds (VOC). 60.312 Section 60.312 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Surface Coating of Metal Furniture § 60.312 Standard for volatile organic compounds (VOC). (a) On...

  5. The Amazonian Floodplains, an ecotype with challenging questions on volatile organic compound (VOC) emissions

    NASA Astrophysics Data System (ADS)

    Kesselmeier, J.

    2012-12-01

    Volatile organic compound (VOC) emissions are affected by a variety of biotic and abiotic factors such as light intensity, temperature, CO2 and drought. Another factor usually overlooked but very important for the tropical rainforest in Amazonia is regular flooding. According to recent estimates, the total Amazonian floodplain area easily ranges up to 700,000 km^2, including whitewater river floodplains (várzea) blackwater regions (igapó) and further clearwater regions. Regarding the total Amazonian wetlands the area sums up to more than 2.000.000 km^2, i.e. 30% of Amazonia. To survive the flooding periods causing anoxic conditions for the root system of up to several months, vegetation has developed several morphological, anatomical and physiological strategies. One is to switch over the root metabolism to fermentation, thus producing ethanol as one of the main products. Ethanol is a toxic metabolite which is transported into the leaves by the transpiration stream. From there it can either be directly emitted into the atmosphere, or can be re-metabolized to acetaldehyde and/or acetate. All of these compounds are volatile enough to be partly released into the atmosphere. We observed emissions of ethanol, acetaldehyde and acetic acid under root anoxia. Furthermore, plant stress induced by flooding also affected leaf primary physiological processes as well as other VOC emissions such as the release of isoprenoids and other volatiles. For example, Hevea spruceana could be identified as a monoterpene emitting tree species behaving differently upon anoxia depending on the origin, with increasing emissions of the species from igapó and decreasing with the corresponding species from várzea. Contrasting such short term inundations, studies of VOC emissions under long term conditions (2-3 months) did not confirm the ethanol/acetaldehyde emissions, whereas emissions of other VOC species decreased considerably. These results demonstrate that the transfer of our knowledge

  6. Detection of new VOC compounds with iCRDS

    NASA Astrophysics Data System (ADS)

    Huang, H.; Leen, J. B.; Gardner, A.; Gupta, M.; Baer, D. S.

    2015-12-01

    The instrument at Los Gatos Research (a member of ABB Inc.) which is based on incoherent cavity ringdown spectroscopy (iCRDS) that operates in the mid-infrared (bands from 860-1060 cm-1 or 970-1280 cm-1) is capable of detecting a broad range of VOCs, in situ, continuously and autonomously, for example, BTEX compounds (benzene, toluene, ethylbenzene, xylene), including differentiation of xylene isomers. Previously, we have demonstrated the measurement of trichloroethylene (TCE) in zero air with a precision of 0.17 ppb (1σ in 4 minutes), and the measurement of tetrachloroethylene (PCE) with a precision of 0.15 ppb (1σ in 4 minutes). Both of these measured precisions exceed the EPA's commercial building action limit, which for TCE is 0.92 ppb (5 µg/m3) and for PCE is 0.29 ppb (2 µg/m3). This ability has been fully demonstrated by the deployment of the instrument to the Superfund site at Moffett Naval Air Station in Mountain View, California where contaminated ground water results in vapor intrusion of TCE and PCE. For two weeks, the instrument operated continuously and autonomously, successfully measuring TCE and PCE concentrations in both the breathing zone and steam tunnel air, in excellent agreement with previous TO-15 data. In this poster, we present laboratory performance data targeting new toxic molecules with the same instrument. We have demonstrated the measurement of trichlorofluolomethane (Freon 11) in zero air with a precision of 1 ppb (3σ at 1075cm-1), and hexafluoropropene in zero air with a precision of about 0.3 ppb (3σ per spectrum). The iCRDS instrument has shown the ability to continuously and autonomously measure sub-ppb levels of toxic VOCs in the lab/field, offering an unprecedented picture of the short term dynamics associated with vapor intrusion and ground water pollution.

  7. Remove volatile organic compounds (VOCs) with membrane separation techniques.

    PubMed

    Zhang, Lin; Weng, Huan-xin; Chen, Huan-lin; Gao, Cong-jie

    2002-04-01

    Membrane separation, a new technology for removing VOCs including pervaporation, vapor permeation, membrane contactor, and membrane bioreactor was presented. Comparing with traditional techniques, these special techniques are an efficient and energy-saving technology. Vapor permeation can be applied to recovery of organic solvents from exhaust streams. Membrane contactor could be used for removing or recovering VOCs from air or wastewater. Pervaporation and vapor permeation are viable methods for removing VOCs from wastewater to yield a VOC concentrate which could either be destroyed by conventional means, or be recycled for reuse.

  8. Gastrophysa polygoni herbivory on Rumex confertus: single leaf VOC induction and dose dependent herbivore attraction/repellence to individual compounds.

    PubMed

    Piesik, Dariusz; Wenda-Piesik, Anna; Kotwica, Karol; Łyszczarz, Alicja; Delaney, Kevin J

    2011-11-15

    We report large induction (>65(fold) increases) of volatile organic compounds (VOCs) emitted from a single leaf of the invasive weed mossy sorrel, Rumex confertus Willd. (Polygonaceae), by herbivory of the dock leaf beetle, Gastrophysa polygoni L. (Coleoptera: Chrysomelidae). The R. confertus VOC blend induced by G. polygoni herbivory included two green leaf volatiles ((Z)-3-hexenal, (Z)-3-hexen-1-yl acetate) and three terpenes (linalool, ß-caryophyllene, (E)-ß-farnesene). Uninjured leaves produced small constitutive amounts of the GLVs and barely detectable amounts of the terpenes. A Y-tube olfactometer bioassay revealed that both sexes of adult G. polygoni were attracted to (Z)-3-hexenal and (Z)-3-hexen-1-yl acetate at a concentration of 300 ng h(-1). No significant G. polygoni attraction or repellence was detected for any VOC at other concentrations (60 and 1500 ng h(-1)). Yet, G. polygoni males and females were significantly repelled by (or avoided) at the highest test concentration (7500 ng h(-1)) of both GLVs and (E)-ß-farnesene. Mated male and female G. polygoni might be attracted to injured R. confertus leaves, but might avoid R. confertus when VOC concentrations (especially the terpene (E)-ß-farnesene) suggest high overall plant injury from conspecifics, G. viridula, or high infestations of other herbivores that release (E)-ß-farnesene (e.g., aphids). Tests in the future will need to examine G. polygoni responses to VOCs emitted directly from uninjured (constitutive) and injured (induced) R. confertus, and examine whether R. confertus VOC induction concentrations increase with greater tissue removal on a single leaf and/or the number of leaves with feeding injury.

  9. Natural vs. Anthropogenic: Combined Measurements of Methane and Volatile Organic Compounds (VOCs) for Investigating Sources of Methane Emissions

    NASA Astrophysics Data System (ADS)

    Zannoni, N.; Assan, S.; Gros, V.; Laville, P.; Loubet, B.; Ciuraru, R.; Baisnee, D.; Bonsang, B.; Sarda Esteve, R.; Chuppin, G.; Truong, F.; Lafouge, F.; Vogel, F. R.

    2016-12-01

    Methane is the second globally most abundant anthropogenic greenhouse gas, whose emissions contribute more than 1/3 of today's additional anthropogenic warming. Methane is emitted from the production and transport of coal, oil and natural gas, as well as from livestock and agricultural practices as well as from natural sources such as e.g. wetlands, freshwaters and wild fauna. Volatile organic compounds constitute less than 0.1% of the total atmospheric composition; however, their emissions and further atmospheric photo-oxidation reactions produce ozone and secondary organic aerosols which have adverse effects on climate and air quality. We measured the concentration of methane and volatile organic compounds (VOCs) over a winter wheat (Triticum aestivum) cropland located in the North-West of Europe during June 2016. The measurements site was located nearby a farm and a methanizer bioreactor, therefore was affected by contrasted sources of emissions: agricultural practices, enteric digestion of livestock, animal manures as well as possible leakages from the biogas unit. Here, measurements of methane, its isotopic composition, and VOCs concentrations are combined to investigate the fingerprint of these sources. Specifically, VOCs, as alkanes which are co-emitted by natural gas, and other compounds as ammonia and NOx will help to unravel the different sources contributions.

  10. Identification and quantitation of volatile organic compounds emitted from dairy silages and other feedstuffs.

    PubMed

    Malkina, Irina L; Kumar, Anuj; Green, Peter G; Mitloehner, Frank M

    2011-01-01

    High ground-level ozone continues to be an important human, animal, and plant health impediment in the United States and especially in California's San Joaquin Valley (SJV). According to California state and regional air quality agencies, dairies are one of the major sources of volatile organic compounds (VOCs) in the SJV. A number of recently conducted studies reported emissions data from different dairy sources. However, limited data are currently available for silage and otherfeed storages on dairies, which could potentially contribute to ozone formation. Because the impact of different VOCs on ozone formation varies significantly from one molecular species to another, detailed characterization of VOC emissions is essential to include all the important contributors to atmospheric chemistry and especially atmospheric reactivity. The present research study identifies and quantifies the VOCs emitted from various silages and other feedstuffs. Experiments were conducted in an environmental chamber under controlled conditions. Almost 80 VOCs were identified and quantified from corn (Zea mays L.), alfalfa (Medicago sativa L.),and cereal (wheat [Triticum aestivum L.] and oat [Avena sativava L.] grains) silages, total mixed ration (TMR), almond (Amygdalus communis L.) shells and hulls using gas chromatography-mass spectrometry and high performance liquid chromatography. The results revealed high concentrations of emitted alcohols and other oxygenated species. Lower concentrations of highly reactive alkenes and aldehydes were also detected. Additional quantitation and monitoring of these emissions are essential for assessment of and response to the specific needs of the regional air quality in the SJV.

  11. 40 CFR 60.502 - Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline terminals.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (VOC) emissions from bulk gasoline terminals. 60.502 Section 60.502 Protection of Environment... SOURCES Standards of Performance for Bulk Gasoline Terminals § 60.502 Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline terminals. On and after the date on which § 60.8(a) requires...

  12. 40 CFR 60.502 - Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline terminals.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (VOC) emissions from bulk gasoline terminals. 60.502 Section 60.502 Protection of Environment... SOURCES Standards of Performance for Bulk Gasoline Terminals § 60.502 Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline terminals. On and after the date on which § 60.8(a) requires...

  13. 40 CFR 60.502 - Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline terminals.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (VOC) emissions from bulk gasoline terminals. 60.502 Section 60.502 Protection of Environment... SOURCES Standards of Performance for Bulk Gasoline Terminals § 60.502 Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline terminals. On and after the date on which § 60.8(a) requires...

  14. 40 CFR 60.502 - Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline terminals.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (VOC) emissions from bulk gasoline terminals. 60.502 Section 60.502 Protection of Environment... SOURCES Standards of Performance for Bulk Gasoline Terminals § 60.502 Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline terminals. On and after the date on which § 60.8(a) requires...

  15. ACTION CONCENTRATION FOR MIXTURES OF VOLATILE ORGANIC COMPOUNDS (VOC) & METHANE & HYDROGEN

    SciTech Connect

    MARUSICH, R.M.

    2006-07-10

    Waste containers may contain volatile organic compounds (VOCs), methane, hydrogen and possibly propane. These constituents may occur individually or in mixtures. Determining if a waste container contains a flammable concentration of flammable gases and vapors (from VOCs) is important to the safety of the handling, repackaging and shipping activities. This report provides the basis for determining the flammability of mixtures of flammable gases and vapors. The concentration of a mixture that is at the lowest flammability limit for that mixture is called the action concentration. The action concentration can be determined using total VOC concentrations or actual concentration of each individual VOC. The concentrations of hydrogen and methane are included with the total VOC or individual VOC concentration to determine the action concentration. Concentrations below this point are not flammable. Waste containers with gas/vapor concentrations at or above the action concentration are considered flammable.

  16. Cross-kingdom effects of plant-plant signaling via volatile organic compounds emitted by tomato (Solanum lycopersicum) plants infested by the greenhouse whitefly (Trialeurodes vaporariorum).

    PubMed

    Ángeles López, Yesenia Ithaí; Martínez-Gallardo, Norma Angélica; Ramírez-Romero, Ricardo; López, Mercedes G; Sánchez-Hernández, Carla; Délano-Frier, John Paul

    2012-11-01

    Volatile organic compounds (VOCs) emitted from plants in response to insect infestation can function as signals for the attraction of predatory/parasitic insects and/or repulsion of herbivores. VOCs also may play a role in intra- and inter-plant communication. In this work, the kinetics and composition of VOC emissions produced by tomato (Solanum lycopersicum) plants infested with the greenhouse whitefly Trialeurodes vaporariorum was determined within a 14 days period. The VOC emission profiles varied concomitantly with the duration of whitefly infestation. A total of 36 different VOCs were detected during the experiment, 26 of which could be identified: 23 terpenoids, plus decanal, decane, and methyl salicylate (MeSA). Many VOCs were emitted exclusively by infested plants, including MeSA and 10 terpenoids. In general, individual VOC emissions increased as the infestation progressed, particularly at 7 days post-infestation (dpi). Additional tunnel experiments showed that a 3 days exposure to VOC emissions from whitefly-infested plants significantly reduced infection by a biotrophic bacterial pathogen. Infection of VOC-exposed plants induced the expression of a likely tomato homolog of a methyl salicylate esterase gene, which preceded the expression of pathogenesis-related protein genes. This expression pattern correlated with reduced susceptibility in VOC-exposed plants. The observed cross-kingdom effect of plant-plant signaling via VOCs probably represents a generalized defensive response that contributes to increased plant fitness, considering that resistance responses to whiteflies and biotrophic bacterial pathogens in tomato share many common elements.

  17. Plant leaves as indoor air passive samplers for volatile organic compounds (VOCs).

    PubMed

    Wetzel, Todd A; Doucette, William J

    2015-03-01

    Volatile organic compounds (VOCs) enter indoor environments through internal and external sources. Indoor air concentrations of VOCs vary greatly but are generally higher than outdoors. Plants have been promoted as indoor air purifiers for decades, but reports of their effectiveness differ. However, while air-purifying applications may be questionable, the waxy cuticle coating on leaves may provide a simple, cost-effective approach to sampling indoor air for VOCs. To investigate the potential use of plants as indoor air VOC samplers, a static headspace approach was used to examine the relationship between leaf and air concentrations, leaf lipid contents and octanol-air partition coefficients (Koa) for six VOCs and four plant species. The relationship between leaf and air concentrations was further examined in an actual residence after the introduction of several chlorinated VOC emission sources. Leaf-air concentration factors (LACFs), calculated from linear regressions of the laboratory headspace data, were found to increase as the solvent extractable leaf lipid content and Koa value of the VOC increased. In the studies conducted in the residence, leaf concentrations paralleled the changing air concentrations, indicating a relatively rapid air to leaf VOC exchange. Overall, the data from the laboratory and residential studies illustrate the potential for plant leaves to be used as cost effective, real-time indoor air VOC samplers. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Characteristics of Ambient Volatile Organic Compounds (VOCs) Measured in Shanghai, China

    PubMed Central

    Cai, Chang-Jie; Geng, Fu-Hai; Tie, Xue-Xi; Yu, Qiong; Peng, Li; Zhou, Guang-Qiang

    2010-01-01

    To better understand the characteristics of ambient abundance of volatile organic compounds (VOCs) in Shanghai, one of the biggest metropolis of China, VOCs were measured with a gas chromatography system equipped with a mass-selective detector (GC/MSD) from July 2006 to February 2010. An intensive measurement campaign was conducted (eight samples per day with a 3 hour interval) during May 2009. The comparison of ambient VOCs collected in different regions of Shanghai shows that the concentrations are slightly higher in the busy commercial area (28.9 ppbv at Xujiaui) than in the urban administrative area (24.3 ppbv at Pudong). However, during the intensive measurement period, the concentrations in the large steel industrial area (28.7 ppbv at Baoshan) were much higher than in the urban administrative area (18 ppbv at Pudong), especially for alkanes, alkenes, and toluene. The seasonal variations of ambient VOC concentrations measured at the Xujiahui sampling site indicate that the VOC concentrations are significantly affected by meteorological conditions (such as wind direction and precipitation). In addition, although alkanes are the most abundant VOCs at the Xujiahui measurement site, the most important VOCs contributing to ozone formation potential (OFP) are aromatics, accounting for 57% of the total OFP. The diurnal variations of VOC concentrations show that VOC concentrations are higher on weekdays than in weekends at the Xujiahui sampling site, suggesting that traffic condition and human activities have important impacts on VOC emissions in Shanghai. The evidence also shows that the major sources of isoprene are mainly resulted from gasoline evaporation at a particular time (06:00–09:00) in the busy commercial area. The results gained from this study provide useful information for better understanding the characteristics of ambient VOCs and the sources of VOCs in Shanghai. PMID:22163629

  19. Volatile organic compounds (VOCs) in exhaled breath of patients with breast cancer in a clinical setting.

    PubMed

    Mangler, Mandy; Freitag, Cornelia; Lanowska, Malgorzata; Staeck, Oliver; Schneider, Achim; Speiser, Dorothee

    2012-10-01

    Carcinogenic products in the exhaled breath of cancer patients are of growing medical interest as they can serve as noninvasive disease markers. Breath analysis can be used as an alternative or complementary diagnostic tool in breast cancer patients who have a different pattern of chemical composition in their breath. This study aims to verify the existence of specific volatile organic compounds (VOCs) in the breath of breast cancer patients. This prospective study included ten patients suffering from breast cancer and ten healthy pair-matched women. Breath samples of each member of the two respective groups were taken and scanned by gas chromatography/mass spectometry for the presence of volatile organic compounds such as alkanes, ketones, halogenated hydrocarbon, aldehydes, and esters. The spectrum of VOCs differed significantly within the two groups. Five specific VOCs could be identified as typical discriminatory markers in the breath samples. Four VOCs were elevated in the healthy controls, one specific VOC was found to be elevated in women affected by breast cancer This pilot study revealed a specific VOC pattern using gas chromatography in the breath of breast cancer patients. Five specific breast cancer-VOCs were identified. At relatively low cost the identification of VOCs may be used to detect breast cancer.

  20. Volatile Organic Compounds (VOCs) in Conventional and High Performance School Buildings in the U.S.

    PubMed

    Zhong, Lexuan; Su, Feng-Chiao; Batterman, Stuart

    2017-01-21

    Exposure to volatile organic compounds (VOCs) has been an indoor environmental quality (IEQ) concern in schools and other buildings for many years. Newer designs, construction practices and building materials for "green" buildings and the use of "environmentally friendly" products have the promise of lowering chemical exposure. This study examines VOCs and IEQ parameters in 144 classrooms in 37 conventional and high performance elementary schools in the U.S. with the objectives of providing a comprehensive analysis and updating the literature. Tested schools were built or renovated in the past 15 years, and included comparable numbers of conventional, Energy Star, and Leadership in Energy and Environmental Design (LEED)-certified buildings. Indoor and outdoor VOC samples were collected and analyzed by thermal desorption, gas chromatography and mass spectroscopy for 94 compounds. Aromatics, alkanes and terpenes were the major compound groups detected. Most VOCs had mean concentrations below 5 µg/m³, and most indoor/outdoor concentration ratios ranged from one to 10. For 16 VOCs, the within-school variance of concentrations exceeded that between schools and, overall, no major differences in VOC concentrations were found between conventional and high performance buildings. While VOC concentrations have declined from levels measured in earlier decades, opportunities remain to improve indoor air quality (IAQ) by limiting emissions from building-related sources and by increasing ventilation rates.

  1. Volatile Organic Compounds (VOCs) in Conventional and High Performance School Buildings in the U.S.

    PubMed Central

    Zhong, Lexuan; Su, Feng-Chiao; Batterman, Stuart

    2017-01-01

    Exposure to volatile organic compounds (VOCs) has been an indoor environmental quality (IEQ) concern in schools and other buildings for many years. Newer designs, construction practices and building materials for “green” buildings and the use of “environmentally friendly” products have the promise of lowering chemical exposure. This study examines VOCs and IEQ parameters in 144 classrooms in 37 conventional and high performance elementary schools in the U.S. with the objectives of providing a comprehensive analysis and updating the literature. Tested schools were built or renovated in the past 15 years, and included comparable numbers of conventional, Energy Star, and Leadership in Energy and Environmental Design (LEED)-certified buildings. Indoor and outdoor VOC samples were collected and analyzed by thermal desorption, gas chromatography and mass spectroscopy for 94 compounds. Aromatics, alkanes and terpenes were the major compound groups detected. Most VOCs had mean concentrations below 5 µg/m3, and most indoor/outdoor concentration ratios ranged from one to 10. For 16 VOCs, the within-school variance of concentrations exceeded that between schools and, overall, no major differences in VOC concentrations were found between conventional and high performance buildings. While VOC concentrations have declined from levels measured in earlier decades, opportunities remain to improve indoor air quality (IAQ) by limiting emissions from building-related sources and by increasing ventilation rates. PMID:28117727

  2. Characterization of volatile organic compounds emitted by barley (Hordeum vulgare L.) roots and their attractiveness to wireworms.

    PubMed

    Gfeller, Aurélie; Laloux, Morgan; Barsics, Fanny; Kati, Djamel Edine; Haubruge, Eric; du Jardin, Patrick; Verheggen, François J; Lognay, Georges; Wathelet, Jean-Paul; Fauconnier, Marie-Laure

    2013-08-01

    Root volatile organic compounds (VOCs), their chemistry and ecological functions have garnered less attention than aboveground emitted plant VOCs. We report here on the identification of VOCs emitted by barley roots (Hordeum vulgare L.). Twenty nine VOCs were identified from isolated 21-d-old roots. The detection was dependent on the medium used for root cultivation. We identified 24 VOCs from 7-d-old roots when plants were cultivated on sterile Hoagland gelified medium, 33 when grown on sterile vermiculite, and 34 on non-sterile vermiculite. The major VOCs were fatty acid derived compounds, including hexanal, methyl hexanoate, (E)-hex-2-enal, 2-pentylfuran, pentan-1-ol, (Z)-2-(pentenyl)-furan, (Z)-pent-2-en-1-ol, hexan-1-ol, (Z)-hex-3-en-1-ol, (E)-hex-2-en-1-ol, oct-1-en-3-ol, 2-ethylhexan-1-ol (likely a contaminant), (E)-non-2-enal, octan-1-ol, (2E,6Z)-nona-2,6-dienal, methyl (E)-non-2-enoate, nonan-1-ol, (Z)-non-3-en-1-ol, (E)-non-2-en-1-ol, nona-3,6-dien-1-ol, and nona-2,6-dien-1-ol. In an olfactometer assay, wireworms (larvae of Agriotes sordidus Illiger, Coleoptera: Elateridae) were attracted to cues emanating from barley seedlings. We discuss the role of individual root volatiles or a blend of the root volatiles detected here and their interaction with CO2 for wireworm attraction.

  3. Emission of VOC Compounds from Ta-Shan Chemical Industrial Park in Middle China

    NASA Astrophysics Data System (ADS)

    Li, Jian; Xie, Chunjuan; Cao, Qun; Yan, Liushui; Zhong, Jiaochan

    2017-03-01

    VOCs emission from a Ta-Shan Chemical Industrial Park in January 1-8, 2014 and summer (July 16-20, 2014) have been studied in this paper. VOCs were collected by the stainlessteel canisters and following pre-concentrate and analyzing by GC/MSD. The results showed that a total of 33 VOC species in winter samplers and 41 VOC species in summer samplers were detected. Among the 41 VOC species detected in the winter and summer samplers, 1-Butene and Ethane were the two most abundant compounds. Their highest average mean concentrations were 6013±1758 and 3188±1025 pptv in summer (contributed more than 12.5% and 4.8 % of the total VOC concentrations), and about 5895±1246 and 2763±789 pptv in winter (contributed more than12.9% and 7.8% of the total VOC concentrations), respectively. In winter, stack emission was found to be the main souce of VOCs emission, while in summer, fugitive emission become the primary source.

  4. Concentrations and flux measurements of volatile organic compounds (VOC) in boreal forest soil

    NASA Astrophysics Data System (ADS)

    Mäki, Mari; Aaltonen, Hermanni; Heinonsalo, Jussi; Hellén, Heidi; Pumpanen, Jukka; Bäck, Jaana

    2017-04-01

    Volatile organic compounds (VOC) impact soil processes as VOCs transmit signals between roots and rhizosphere (Ditengou et al., 2015), VOCs can regulate microbial activity (Asensio et al., 2012), and VOCs can also promote root growth (Hung et al., 2012). Belowground concentrations of VOCs have not been measured in situ and for this reason, knowledge of how different soil organisms such as roots, rhizosphere and decomposers contribute to VOC production is limited. The aim of this study was to determine and quantify VOC fluxes and concentrations of different horizons from boreal forest soil. The VOC concentrations and fluxes were measured from Scots pine (Pinus sylvestris) forest soil at the SMEAR II station in southern Finland from 21th of April to 2nd of December in 2016. VOC fluxes were measured using dynamic (flow-through) chambers from five soil collars placed on five different locations. VOC concentrations were also measured in each location from four different soil horizons with the measurement depth 1-107 cm. VOCs were collected from underground gas collectors into the Tenax-Carbopack-B adsorbent tubes using portable pumps ( 100 ml min-1). The VOC concentrations and fluxes of isoprene, 11 monoterpenes, 13 sesquiterpenes and different oxygenated VOCs were measured. Sample tubes were analyzed using thermal desorption-gas chromatograph-mass spectrometry (TD-GC-MS). Soil temperature and soil water content were continuously monitored for each soil horizon. Our preliminary results show that the primary source of VOCs is organic soil layer and the contribution of mineral soil to the VOC formation is minor. VOC fluxes and concentrations were dominated by monoterpenes such as α-pinene, camphene, β-pinene, and Δ3-carene. Monoterpene concentration is almost 10-fold in organic soil compared to the deeper soil layers. However, the highest VOC fluxes on the soil surface were measured in October, whereas the monoterpene concentrations in organic soil were highest in July

  5. Volatile Organic Compound (VOC) Removal by Vapor Permeation at Low VOC Concentrations: Laboratory Scale Results and Modeling for Scale Up

    PubMed Central

    Rebollar-Perez, Georgette; Carretier, Emilie; Lesage, Nicolas; Moulin, Philippe

    2011-01-01

    Petroleum transformation industries have applied membrane processes for solvent and hydrocarbon recovery as an economic alternative to reduce their emissions and reuse evaporated components. Separation of the volatile organic compounds (VOCs) (toluene-propylene-butadiene) from air was performed using a poly dimethyl siloxane (PDMS)/α-alumina membrane. The experimental set-up followed the constant pressure/variable flow set-up and was operated at ∼21 °C. The membrane is held in a stainless steel module and has a separation area of 55 × 10−4 m2. Feed stream was set to atmospheric pressure and permeate side to vacuum between 3 and 5 mbar. To determine the performance of the module, the removed fraction of VOC was analyzed by Gas Chromatography/Flame Ionization Detector (GC/FID). The separation of the binary, ternary and quaternary hydrocarbon mixtures from air was performed at different flow rates and more especially at low concentrations. The permeate flux, permeance, enrichment factor, separation efficiency and the recovery extent of the membrane were determined as a function of these operating conditions. The permeability coefficients and the permeate flux through the composite PDMS-alumina membrane follow the order given by the Hildebrand parameter: toluene > 1,3-butadiene > propylene. The simulated data for the binary VOC/air mixtures showed fairly good agreement with the experimental results in the case of 1,3-butadiene and propylene. The discrepancies observed for toluene permeation could be minimized by taking into account the effects of the porous support and an influence of the concentration polarization. Finally, the installation of a 0.02 m2 membrane module would reduce 95% of the VOC content introduced at real concentration conditions used in the oil industry. PMID:24957498

  6. Mixing ratios of volatile organic compounds (VOCs) in the atmosphere of Karachi, Pakistan

    NASA Astrophysics Data System (ADS)

    Barletta, Barbara; Meinardi, Simone; Simpson, Isobel J.; Khwaja, Haider A.; Blake, Donald R.; Rowland, F. Sherwood

    Mixing ratios of carbon monoxide (CO), methane (CH 4), non-methane hydrocarbons, halocarbons and alkyl nitrates (a total of 72 species) were determined for 78 whole air samples collected during the winter of 1998-1999 in Karachi, Pakistan. This is the first time that volatile organic compound (VOC) levels in Karachi have been extensively characterized. The overall air quality of the urban environment was determined using air samples collected at six locations throughout Karachi. Methane (6.3 ppmv) and ethane (93 ppbv) levels in Karachi were found to be much higher than in other cities that have been studied. The very high CH 4 levels highlight the importance of natural gas leakage in Karachi. The leakage of liquefied petroleum gas contributes to elevated propane and butane levels in Karachi, although the propane and butane burdens were lower than in other cities (e.g., Mexico City, Santiago). High levels of benzene (0.3-19 ppbv) also appear to be of concern in the Karachi urban area. Vehicular emissions were characterized using air samples collected along the busiest thoroughfare of the city (M.A. Jinnah Road). Emissions from vehicular exhaust were found to be the main source of many of the hydrocarbons reported here. Significant levels of isoprene (1.2 ppbv) were detected at the roadside, and vehicular exhaust is estimated to account for about 20% of the isoprene observed in Karachi. 1,2-Dichloroethane, a lead scavenger added to leaded fuel, was also emitted by cars. The photochemical production of ozone (O 3) was calculated for CO and the various VOCs using the Maximum Incremental Reactivity (MIR) scale. Based on the MIR scale, the leading contributors to O 3 production in Karachi are ethene, CO, propene, m-xylene and toluene.

  7. A parsimonious model for the release of volatile organic compounds (VOCs) encapsulated in products

    NASA Astrophysics Data System (ADS)

    Huang, Lei; Jolliet, Olivier

    2016-02-01

    Studies have demonstrated that near-field chemical intakes may exceed environmentally mediated exposures and are therefore essential to be considered when assessing chemical emissions across a product's life cycle. VOCs encapsulated in materials/products can be a major emission source in the use phase. Previous models describing such emissions require complex analytical or numerical solutions, which poses a great computational burden and lack transparency for use in high-throughput screening of chemicals. In the present study, we adapted a model which describes VOC emissions from building materials and subsequent removal by ventilation, and decoupled the material and air governing equations by assuming a pseudo-steady-state between emission and loss. Results of this decoupled model show good agreement with the original more complex model and the experimental data. The solution of this decoupled model for mass fraction emitted, which still consists of an infinite sum of exponential terms, is further reduced to a sum of only two exponentials with parameters which can be predicted from physiochemical properties using explicit equations. Results of this simple two-exponential model agree well with the original full model over a 15-year time period with R-square greater than 0.99 for a wide range of compounds and material thicknesses. Moreover, the chemical concentration at the material surface can be simply calculated from the derivative of this two-exponential model, which also agrees well with the surface concentration calculated using the original full model. The present parsimonious approach greatly reduces the computational burden, and can be easily implemented for high-throughput screening.

  8. Extended Research on Detection of Deception Using Volatile Organic Compound (VOC) Emissions

    SciTech Connect

    Center for Human Reliability Studies

    2006-06-01

    A system that captures and analyzes volatile organic compound (VOC) emissions from skin surfaces may offer a viable alternative method to the polygraph instrument currently in use for detecting deception in U.S. government settings. Like the involuntary autonomic central nervous system response data gathered during polygraph testing, VOC emissions from the skin may provide data that can be used to detect stress caused by deception. Detecting VOCs, then, may present a noninvasive, non-intrusive method for observing, recording, and quantifying evidence of stress or emotional change.

  9. Process-specific emission characteristics of volatile organic compounds (VOCs) from petrochemical facilities in the Yangtze River Delta, China.

    PubMed

    Mo, Ziwei; Shao, Min; Lu, Sihua; Qu, Hang; Zhou, Mengyi; Sun, Jin; Gou, Bin

    2015-11-15

    Process-specific emission characteristics of volatile organic compounds (VOCs) from petrochemical facilities were investigated in the Yangtze River Delta, China. Source samples were collected from various process units in the petrochemical, basic chemical, and chlorinated chemical plants, and were measured using gas chromatography-mass spectrometry/flame ionization detection. The results showed that propane (19.9%), propene (11.7%), ethane (9.5%) and i-butane (9.2%) were the most abundant species in the petrochemical plant, with propene at much higher levels than in petrochemical profiles measured in other regions. Styrene (15.3%), toluene (10.3%) and 1,3-butadiene (7.5%) were the major species in the basic chemical industry, while halocarbons, especially dichloromethane (15.2%) and chloromethane (7.5%), were substantial in the chlorinated chemical plant. Composite profiles were calculated using a weight-average approach based on the VOC emission strength of various process units. Emission profiles for an entire petrochemical-related industry were found to be process-oriented and should be established considering the differences in VOC emissions from various manufacturing facilities. The VOC source reactivity and carcinogenic risk potential of each process unit were also calculated in this study, suggesting that process operations mainly producing alkenes should be targeted for possible controls with respect to reducing the ozone formation potential, while process units emitting 1,3-butadiene should be under priority control in terms of toxicity. This provides a basis for further measurements of process-specific VOC emissions from the entire petrochemical industry. Meanwhile, more representative samples should be collected to reduce the large uncertainties.

  10. Volatile organic compounds (VOCs) source profiles of on-road vehicle emissions in China.

    PubMed

    Hong-Li, Wang; Sheng-Ao, Jing; Sheng-Rong, Lou; Qing-Yao, Hu; Li, Li; Shi-Kang, Tao; Cheng, Huang; Li-Ping, Qiao; Chang-Hong, Chen

    2017-12-31

    Volatile Organic Compounds (VOCs) source profiles of on-road vehicles were widely studied as their critical roles in VOCs source apportionment and abatement measures in megacities. Studies of VOCs source profiles from on-road motor vehicles from 2001 to 2016 were summarized in this study, with a focus on the comparisons among different studies and the potential impact of different factors. Generally, non-methane hydrocarbons dominated the source profile of on-road vehicle emissions. Carbonyls, potential important components of vehicle emission, were seldom considered in VOCs emissions of vehicles in the past and should be paid more attention to in further study. VOCs source profiles showed some variations among different studies, and 6 factors were extracted and studied due to their impact to VOCs source profile of on-road vehicles. Vehicle types, being dependent on engine types, and fuel types were two dominant factors impacting VOCs sources profiles of vehicles. In comparison, impacts of ignitions, driving conditions and accumulated mileage were mainly due to their influence on the combustion efficiency. An opening and interactive database of VOCs from vehicle emissions was critically essential in future, and mechanisms of sharing and inputting relative research results should be formed to encourage researchers join the database establishment. Correspondingly, detailed quality assurance and quality control procedures were also very important, which included the information of test vehicles and test methods as detailed as possible. Based on the community above, a better uncertainty analysis could be carried out for the VOCs emissions profiles, which was critically important to understand the VOCs emission characteristics of the vehicle emissions. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Diversity of the volatile organic compounds emitted by 55 species of tropical trees: a survey in French Guiana.

    PubMed

    Courtois, Elodie A; Paine, C E Timothy; Blandinieres, Pierre-Alain; Stien, Didier; Bessiere, Jean-Marie; Houel, Emeline; Baraloto, Christopher; Chave, Jerome

    2009-11-01

    Volatile organic compounds (VOCs) are produced by a broad range of organisms, from bacteria to mammals, and they represent a vast chemical diversity. In plants, one of the preeminent roles of VOCs is their repellent or cytotoxic activity, which helps the plant deter its predators. Most studies on VOCs emitted by vegetative parts have been conducted in model plant species, and little is known about patterns of VOC emissions in diverse plant communities. We conducted a survey of the VOCs released immediately after mechanical damage of the bark and the leaves of 195 individual trees belonging to 55 tropical tree species in a lowland rainforest of French Guiana. We discovered a remarkably high chemical diversity, with 264 distinct VOCs and a mean of 37 compounds per species. Two monoterpenes (alpha-pinene and limonene) and two sesquiterpenes (beta-caryophyllene and alpha-copaene), which are known to have cytotoxic and deterrent effects, were the most frequent compounds in the sampled species. As has been established for floral scents, the blend of VOCs is largely species-specific and could be used to discriminate among 43 of the 55 sampled species. The species with the most diverse blends were found in the Sapindales, Laurales, and Magnoliales, indicating that VOC diversity is not uniformly distributed among tropical species. Interspecific variation in chemical diversity was caused mostly by variation in sesquiterpenes. This study emphasizes three aspects of VOC emission by tropical tree species: the species-specificity of the mixtures, the importance of sesquiterpenes, and the wide-ranging complexity of the mixtures.

  12. 40 CFR 60.112 - Standard for volatile organic compounds (VOC).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for volatile organic compounds (VOC). 60.112 Section 60.112 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... After June 11, 1973, and Prior to May 19, 1978 § 60.112 Standard for volatile organic compounds...

  13. 40 CFR 60.112 - Standard for volatile organic compounds (VOC).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for volatile organic compounds (VOC). 60.112 Section 60.112 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... After June 11, 1973, and Prior to May 19, 1978 § 60.112 Standard for volatile organic compounds...

  14. 40 CFR 60.112b - Standard for volatile organic compounds (VOC).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for volatile organic compounds... for Volatile Organic Liquid Storage Vessels (Including Petroleum Liquid Storage Vessels) for Which... organic compounds (VOC). (a) The owner or operator of each storage vessel either with a design...

  15. 40 CFR 60.112 - Standard for volatile organic compounds (VOC).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for volatile organic compounds (VOC). 60.112 Section 60.112 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... After June 11, 1973, and Prior to May 19, 1978 § 60.112 Standard for volatile organic compounds...

  16. 40 CFR 60.112 - Standard for volatile organic compounds (VOC).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for volatile organic compounds (VOC). 60.112 Section 60.112 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... After June 11, 1973, and Prior to May 19, 1978 § 60.112 Standard for volatile organic compounds...

  17. 40 CFR 60.112b - Standard for volatile organic compounds (VOC).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for volatile organic compounds... for Volatile Organic Liquid Storage Vessels (Including Petroleum Liquid Storage Vessels) for Which... organic compounds (VOC). (a) The owner or operator of each storage vessel either with a design...

  18. 40 CFR 60.112b - Standard for volatile organic compounds (VOC).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for volatile organic compounds... for Volatile Organic Liquid Storage Vessels (Including Petroleum Liquid Storage Vessels) for Which... organic compounds (VOC). (a) The owner or operator of each storage vessel either with a design...

  19. 40 CFR 60.112b - Standard for volatile organic compounds (VOC).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for volatile organic compounds... for Volatile Organic Liquid Storage Vessels (Including Petroleum Liquid Storage Vessels) for Which... organic compounds (VOC). (a) The owner or operator of each storage vessel either with a design...

  20. 40 CFR 60.112 - Standard for volatile organic compounds (VOC).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for volatile organic compounds (VOC). 60.112 Section 60.112 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... After June 11, 1973, and Prior to May 19, 1978 § 60.112 Standard for volatile organic compounds...

  1. Development of a Combined Real Time Monitoring and Integration Analysis System for Volatile Organic Compounds (VOCs)

    PubMed Central

    Oka, Kentaro; Iizuka, Atsushi; Inoue, Yasuo; Mizukoshi, Atsushi; Noguchi, Miyuki; Yamasaki, Akihiro; Yanagisawa, Yukio

    2010-01-01

    A combined integration analysis and real time monitoring (Peak Capture System) system was developed for volatile organic compounds (VOCs). Individual integration analysis and real time monitoring can be used to qualitatively and quantitatively analyze VOCs in the atmosphere and in indoor environments and determine the variation in total VOC (TVOC) concentration with time, respectively. In the Peak Capture System, real time monitoring was used to predict future elevations in the TVOC concentration (peak), and this was used an indicator of when to collect (capture) ambient air samples for integration analysis. This enabled qualitative and quantitative analysis of VOCs when the TVOC concentration was high. We developed an algorithm to predict variation in the TVOC concentration, and constructed an automatic system to initiate air sampling for integration analysis. With the system, auto-sampling and analysis of VOCs in a conventional house were conducted. In comparison with background concentrations, the results of peak analysis enabled identification of compounds whose concentration rose. This also enabled an evaluation of possible VOC emission sources. PMID:21317996

  2. Detection of the volatile organic compounds emitted from paints using optical fibre long period grating modified with the mesoporous nano-scale coating

    NASA Astrophysics Data System (ADS)

    Hromadka, Jiri; James, Stephen; Davis, Frank; Tatam, Ralph P.; Crump, Derrick; Korposh, Sergiy

    2015-09-01

    An optical fibre long period grating (LPG) modified with a mesoporous film infused with a calixarene as a functional compound was employed for the detection of a mixture of volatile organic compounds (VOCs). The sensing mechanism is based on the transduction of the refractive index change induced by the complexion of the VOCs with calixarene into a change in the form of the transmission spectrum of the LPG. An LPG, modified with a calixarene-infused coating comprising 5 cycles of silica nanoparticles/poly(allylamine hydrochloride) polycation (SiO2/PAH), was exposed to mixture of VOCs emitted from paint at conditions simulating ISO standards test (16000-10).

  3. [Variation characteristics of ambient volatile organic compounds (VOCs) in Nanjing northern suburb, China].

    PubMed

    An, Jun-Lin; Zhu, Bin; Li, Yong-Yu

    2013-12-01

    Based on the data of volatile organic compounds (VOCs) collected continuously from Mar 1, 2011 to Feb 29, 2012 in the northern suburb of Nanjing, characteristics of their temporal variation, photochemical reactivity of their compositions and source characteristics of VOCs were analyzed. The results showed that the mean value of VOCs mixing ratios was 43.52 x 10(-9) (volume fraction). There was an obvious seasonal cycle of VOCs, with the maximum in summer and minimum in winter. Diurnal variation of VOCs mixing ratios showed a very clear cycle, with higher average VOCs mixing ratios at nighttime than at daytime. The seasonal trend of VOCs mixing ratios at night was in the order of summer > autumn > spring > winter, whereas the order during daytime was winter > summer > spring > winter. Mixing ratio of VOCs had greater diurnal amplitude in autumn and lesser in winter. Alkanes and alkenes had greater diurnal amplitude in autumn. Aromatics and alkenes had greater diurnal amplitude in spring. Using the propylene-equal mixing ratios method, alkenes was found to be the largest part of VOCs, followed by aromatics, and alkanes was the least. The ratios of T/B, E/B and X/B were 1.23, 0.95 and 0.81, respectively, possibly due to the aging of the air mass at this site. The robust vehicular indicator, 3-methylpentane, which is an intrinsic component gasoline, was used to estimate the contributions of traffic versus non-traffic sources. The non-traffic source contribution was significant for ethene (85%), toluene (71%) and m, p-xylene (82%).

  4. Measurement of volatile organic compounds emitted in libraries and archives: an inferential indicator of paper decay?

    PubMed Central

    2012-01-01

    Background A sampling campaign of indoor air was conducted to assess the typical concentration of indoor air pollutants in 8 National Libraries and Archives across the U.K. and Ireland. At each site, two locations were chosen that contained various objects in the collection (paper, parchment, microfilm, photographic material etc.) and one location was chosen to act as a sampling reference location (placed in a corridor or entrance hallway). Results Of the locations surveyed, no measurable levels of sulfur dioxide were detected and low formaldehyde vapour (< 18 μg m-3) was measured throughout. Acetic and formic acids were measured in all locations with, for the most part, higher acetic acid levels in areas with objects compared to reference locations. A large variety of volatile organic compounds (VOCs) was measured in all locations, in variable concentrations, however furfural was the only VOC to be identified consistently at higher concentration in locations with paper-based collections, compared to those locations without objects. To cross-reference the sampling data with VOCs emitted directly from books, further studies were conducted to assess emissions from paper using solid phase microextraction (SPME) fibres and a newly developed method of analysis; collection of VOCs onto a polydimethylsiloxane (PDMS) elastomer strip. Conclusions In this study acetic acid and furfural levels were consistently higher in concentration when measured in locations which contained paper-based items. It is therefore suggested that both acetic acid and furfural (possibly also trimethylbenzenes, ethyltoluene, decane and camphor) may be present in the indoor atmosphere as a result of cellulose degradation and together may act as an inferential non-invasive marker for the deterioration of paper. Direct VOC sampling was successfully achieved using SPME fibres and analytes found in the indoor air were also identified as emissive by-products from paper. Finally a new non

  5. Contribution of low vapor pressure-volatile organic compounds (LVP-VOCs) from consumer products to ozone formation in urban atmospheres

    NASA Astrophysics Data System (ADS)

    Shin, Hyeong-Moo; McKone, Thomas E.; Bennett, Deborah H.

    2015-05-01

    Because recent laboratory testing indicates that some low vapor pressure-volatile organic compounds (LVP-VOC) solvents readily evaporate at ambient conditions, LVP-VOCs used in some consumer product formulations may contribute to ozone formation. The goal of this study is to determine the fraction of LVP-VOCs available for ozone formation from the use of consumer products for two hypothetical emissions. This study calculates and compares the fraction of consumed product available for ozone formation as a result of (a) volatilization to air during use and (b) down-the-drain disposal. The study also investigates the impact of different modes of releases on the overall fraction available in ambient air for ozone formation. For the portion of the LVP-VOCs volatilized to air during use, we applied a multi-compartment mass-balance model to track the fate of emitted LVP-VOCs in a multimedia urban environment. For the portion of the LVP-VOCs disposed down the drain, we used a wastewater treatment plant (WWTP) fate model to predict the emission rates of LVP-VOCs to ambient air at WWTPs or at the discharge zone of the facilities and then used these results as emissions in the multimedia urban environment model. In a WWTP, the LVP-VOCs selected in this study are primarily either biodegraded or removed via sorption to sludge depending on the magnitude of the biodegradation half-life and the octanol-water partition coefficient. Less than 0.2% of the LVP-VOCs disposed down the drain are available for ozone formation. In contrast, when the LVP-VOC in a consumer product is volatilized from the surface to which it has been applied, greater than 90% is available for photochemical reactions either at the source location or in the downwind areas. Comparing results from these two modes of releases allows us to understand the importance of determining the fraction of LVP-VOCs volatilized versus disposed down the drain when the product is used by consumers. The results from this study

  6. Volatile organic compounds emitted after leaf wounding: On-line analysis by proton-transfer-reaction mass spectrometry

    NASA Astrophysics Data System (ADS)

    Fall, Ray; Karl, Thomas; Hansel, Armin; Jordan, Alfons; Lindinger, Werner

    1999-07-01

    Volatile organic compounds (VOCs) released from vegetation, including wound-induced VOCs, can have important effects on atmospheric chemistry. The analytical methods for measuring wound-induced VOCs, especially the hexenal family of VOCs (hexenals, hexenols, and hexenyl esters), are complicated by their chemical instability and the transient nature of their formation after leaf and stem wounding. Here we demonstrate that formation and emission of hexenal family compounds can be monitored on-line using proton-transfer-reaction mass spectrometry (PTR-MS), avoiding the need for preconcentration or chromatography. These measurements allow direct analysis of the rapid emission of the parent compound, (Z)-3-hexenal, within 1-2 s of wounding of aspen leaves and then its disappearance and the appearance of its metabolites including (E)-2-hexenal, hexenols, and hexenyl acetates. Similar results were seen in wounded beech leaves and clover. The emission of hexenal family compounds was proportional to the extent of wounding, was not dependent on light, occurred in attached or detached leaves, and was greatly enhanced as detached leaves dried out. Emission of (Z)-3-hexenal from detached drying aspen leaves averaged 500 μg C g-1 (dry leaf weight). Leaf wound compounds were not emitted in a nitrogen atmosphere but were released within seconds of reintroduction of oxygen; this indicates that there are not large pools of hexenyl compounds in leaves. The PTR-MS method also allows the simultaneous detection of less abundant hexanal family VOCs including hexanal, hexanol, and hexyl acetate and VOCs formed in the light (isoprene) or during anoxia (acetaldehyde). PTR-MS may be a useful tool for the analysis of VOC emissions resulting from grazing, herbivory, and other physical damage to vegetation, from harvesting of crops, and from senescing leaves.

  7. Volatile organic compounds (VOCs) in photochemically aged air from the Eastern and Western Mediterranean

    NASA Astrophysics Data System (ADS)

    Derstroff, Bettina; Stoenner, Christof; Klüpfel, Thomas; Sauvage, Carina; Crowley, John; Phillips, Gavin; Parchatka, Uwe; Lelieveld, Jos; Williams, Jonathan

    2015-04-01

    In summer 2014 a comprehensively instrumented measurement campaign (CYPHEX) was conducted in northwest Cyprus in order to investigate atmospheric oxidation chemistry in the Mediterranean region. The site was periodically influenced by the northerly Etesian winds advecting air from Eastern Europe (Turkey and Greece) and from westerly winds bringing more photochemically processed emissions from Western Europe (Spain and France). In this study the data from a Proton Transfer Reaction Time of Flight Mass Spectrometer (PTR-TOF-MS) are analyzed. Generally, oxidized volatile organic compounds (OVOCs) such as methanol and acetone were measured in high mixing ratios (max. 9.5 ppb, min. 1.3 ppb, average 3.2 ppb for methanol, max. 7.9 ppb, min. 1.3 ppb, average 2.4 ppb for acetone ) while precursors like propane showed low values (max. 500 ppt). This demonstrates that the air measured was oxidized to a high degree over the Mediterranean Sea. Low values of acetonitrile throughout the campaign indicated no significant influence of biomass burning on the data. Temporal variations in VOC mixing ratios and precursor/product ratios over the campaign can be explained by using the HYSPLIT backward trajectory model which delineated air masses originating from Eastern and Western Europe. Diel variations of reactive VOCs such as isoprene and terpenes were also observed at the site. A sharp increase in isoprene and monoterpenes at circa 9:00 local time indicated that the 600 m hilltop site was influenced by ascending boundary layer air at this time. In this study, particular emphasis is placed on acetic (ethanoic) acid measured by PTR- TOF-MS and calibrated by a permeation source. Acetic acid is an atmospheric oxidation product of multiple volatile organic compounds, emitted directly from vegetation, and found in abundance in the Mediterranean region (max. 2.7 ppb, min. 0.2 ppb, average 0.8 ppb). Acetic acid contributes to the acidity of precipitation in remote areas, can be incorporated

  8. [Characteristics and source apportionment of volatile organic compounds (VOCs) in the northern suburb of Nanjing].

    PubMed

    An, Jun-lin; Zhu, Bin; Wang, Hong-lei; Yang, Hui

    2014-12-01

    Based on the data of volatile organic compounds (VOCs) collected continuously from 1st Mar, 2011 to 29th Feb, 2012 in the northern suburb of Nanjing, characteristics of their variability, differences of ratios of tracers and source apportionment by principal component analysis/absolute principal component scores (PCA/APCS) were analyzed. The results showed that the total VOCs mixing ratios were 43.52 x 10(-9), which accounted for 45.1% of alkanes, alkenes for 25.3%, alkyne for 7.3%, and aromatics for 22.3%. There was an obviously seasonal variation of VOCs, with the maximum in summer and the minimum in winter. There was an obvious seasonal variation of VOCs component, with highest alkanes in winter, highest alkenes in summer, highest aromatic in spring, and highest alkyne in winter. By using the specific pollutant ratios ( hydrocarbons/acetylene and toluene/benzene) method, it indicated that the observation site was greatly affected by the surrounding industrial areas. Source analysis of VOCs by PCA/APCS mode showed that the sources consisted of industrial production sources, automobile emission sources, combustion sources, industrial production volatilization sources, solvent use sources and biogenic emission sources. In addition, there were seasonal variations. Overall, the sources related to industrial production activities represented 45% - 63% of VOCs, and they were followed by automobile emission sources, which represented 34% - 50%.

  9. Age matters: the effects of volatile organic compounds emitted by Trichoderma atroviride on plant growth.

    PubMed

    Lee, Samantha; Hung, Richard; Yap, Melanie; Bennett, Joan W

    2015-06-01

    Studying the effects of microbial volatile organic compounds (VOCs) on plant growth is challenging because the production of volatiles depends on many environmental factors. Adding to this complexity, the method of volatile exposure itself can lead to different responses in plants and may account for some of the contrasting results. In this work, we present an improved experimental design, a plate-within-a-plate method, to study the effects of VOCs produced by filamentous fungi. We demonstrate that the plant growth response to VOCs is dependent on the age of the plant and fungal cultures. Plants exposed to volatiles emitted by 5-day-old Trichoderma atroviride for 14 days exhibited inhibition, while plants exposed to other exposure conditions had growth promotion or no significant change. Using GC-MS, we compared fungal volatile emission of 5-day-old and 14-day-old T. atroviride. As the fungi aged, a few compounds were no longer detected, but 24 new compounds were discovered.

  10. Effect of exposure to volatile organic compounds (VOCs) on airway inflammatory response in mice.

    PubMed

    Wang, Fan; Li, Chonglei; Liu, Wei; Jin, Yihe

    2012-01-01

    Volatile organic compounds (VOCs) are the main substances causing multiple chemical sensitivity reactions in human. The effects of single VOCs exposure on airway inflammatory responses in mice lung have been reported. Previous studies have demonstrated the role of reactive oxygen species (ROS) in lung inflammation induced by single VOCs inhalation. However, effects of VOCs exposure on NO signaling and neurological signaling pathways in airway remain less clear. We exposed male Kunming mice to filtered air (0) and four types of VOCs mixture (formaldehyde, benzene, toluene, and xylene) treated air. Group 1 is 1.0, 1.1, 2.0 and 2.0 mg/m(3), group 2 is 3.0, 3.3, 6.0 and 6.0 mg/m(3), group 3 is 5.0, 5.5, 10.0 and 10.0 mg/m(3), group 4 is 10.0, 11.0, 20.0 and 20.0 mg/m(3), which respectively corresponded to 10, 30, 50 and 100 times of indoor air quality standard in China 2 hr per day, 5 days per week, for 2 weeks in the whole body exposure chamber. One day following VOCs exposure, we collected lung, bronchoalveolar lavage fluid (BALF) from each mouse and examined oxidative stress markers, cellular infiltration and production of cytokines, neurotrophin and substance P. We found that VOCs exposure influenced significantly NOS activity, GSH, or IL-6 concentration. The number of total cells, macrophages and eosinophils increased significantly in group 4. In addition, the production of interferon-gamma (IFN-γ) and substance P were significantly decreased. In contrast, neurotrophin-3 production in BALF was significantly increased in group 3 and 4. Our findings suggest that NO signaling pathways may induce airway inflammatory in short term VOCs exposure mice and the airway inflammatory response may be modulated by neurological signaling.

  11. Growth promotion of Lactuca sativa in response to volatile organic compounds emitted from diverse bacterial species.

    PubMed

    Fincheira, Paola; Venthur, Herbert; Mutis, Ana; Parada, Maribel; Quiroz, Andrés

    2016-12-01

    Agrochemicals are currently used in horticulture to increase crop production. Nevertheless, their indiscriminate use is a relevant issue for environmental and legal aspects. Alternative tools for reducing fertilizers and synthetic phytohormones are being investigated, such as the use of volatile organic compounds (VOCs) as growth inducers. Some soil bacteria, such as Pseudomonas and Bacillus, stimulate Arabidopsis and tobacco growth by releasing VOCs, but their effects on vegetables have not been investigated. Lactuca sativa was used as model vegetable to investigate bacterial VOCs as growth inducers. We selected 10 bacteria strains, belonging to Bacillus, Staphylococcus and Serratia genera that are able to produce 3-hydroxy-2-butanone (acetoin), a compound with proven growth promoting activity. Two-day old-seedlings of L. sativa were exposed to VOCs emitted by the selected bacteria grown in different media cultures for 7 days. The results showed that the VOCs released from the bacteria elicited an increase in the number of lateral roots, dry weight, root growth and shoot length, depending on the media used. Three Bacillus strains, BCT53, BCT9 and BCT4, were selected according to its their growth inducing capacity. The BCT9 strain elicited the greatest increases in dry weight and primary root length when L. sativa seedlings were subjected to a 10-day experiment. Finally, because acetoin only stimulated root growth, we suggest that other volatiles could be responsible for the growth promotion of L. sativa. In conclusion, our results strongly suggest that bacteria volatiles can be used as growth-inducers as alternative or complementary strategies for application in horticulture species. Copyright © 2016 Elsevier GmbH. All rights reserved.

  12. AMBIENT LEVEL VOLATILE ORGANIC COMPOUND (VOC) MONITORING USING SOLID ADSORBANTS - RECENT U.S. EPA STUDIES

    EPA Science Inventory

    Ambient air spiked with 1-10 ppbv concentrations of 41 toxic volatile organic compounds (VOCs) listed in U.S. Environmental Protection Agency (EPA) Compendium Method TO-14A was monitored using solid sorbents for sample collection and a Varian Saturn 2000 ion trap mass spectrome...

  13. AMBIENT LEVEL VOLATILE ORGANIC COMPOUND (VOC) MONITORING USING SOLID ADSORBANTS - RECENT U.S. EPA STUDIES

    EPA Science Inventory

    Ambient air spiked with 1-10 ppbv concentrations of 41 toxic volatile organic compounds (VOCs) listed in U.S. Environmental Protection Agency (EPA) Compendium Method TO-14A was monitored using solid sorbents for sample collection and a Varian Saturn 2000 ion trap mass spectrome...

  14. 40 CFR 60.112a - Standard for volatile organic compounds (VOC).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standard for volatile organic compounds (VOC). 60.112a Section 60.112a Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Commenced After May 18, 1978, and Prior to July 23, 1984 § 60.112a Standard for volatile organic...

  15. 40 CFR 60.112a - Standard for volatile organic compounds (VOC).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standard for volatile organic compounds (VOC). 60.112a Section 60.112a Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Commenced After May 18, 1978, and Prior to July 23, 1984 § 60.112a Standard for volatile organic...

  16. 40 CFR 60.112a - Standard for volatile organic compounds (VOC).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standard for volatile organic compounds (VOC). 60.112a Section 60.112a Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Commenced After May 18, 1978, and Prior to July 23, 1984 § 60.112a Standard for volatile organic...

  17. 40 CFR 60.112a - Standard for volatile organic compounds (VOC).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standard for volatile organic compounds (VOC). 60.112a Section 60.112a Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Commenced After May 18, 1978, and Prior to July 23, 1984 § 60.112a Standard for volatile organic...

  18. 40 CFR 60.112a - Standard for volatile organic compounds (VOC).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standard for volatile organic compounds (VOC). 60.112a Section 60.112a Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Commenced After May 18, 1978, and Prior to July 23, 1984 § 60.112a Standard for volatile organic...

  19. Productions of Volatile Organic Compounds (VOCs) in Surface Waters from Reactions with Atmospheric Ozone

    NASA Astrophysics Data System (ADS)

    Hopkins, Frances; Bell, Thomas; Yang, Mingxi

    2017-04-01

    Ozone (O3) is a key atmospheric oxidant, greenhouse gas and air pollutant. In marine environments, some atmospheric ozone is lost by reactions with aqueous compounds (e.g. dissolved organic material, DOM, dimethyl sulfide, DMS, and iodide) near the sea surface. These reactions also lead to formations of volatile organic compounds (VOCs). Removal of O3 by the ocean remains a large uncertainty in global and regional chemical transport models, hampering coastal air quality forecasts. To better understand the role of the ocean in controlling O3 concentrations in the coastal marine atmosphere, we designed and implemented a series of laboratory experiments whereby ambient surface seawater was bubbled with O3-enriched, VOC-free air in a custom-made glass bubble equilibration system. Gas phase concentrations of a range of VOCs were monitored continuously over the mass range m/z 33 - 137 at the outflow of the bubble equilibrator by a proton transfer reaction - mass spectrometer (PTR-MS). Gas phase O3 was also measured at the input and output of the equilibrator to monitor the uptake due to reactions with dissolved compounds in seawater. We observed consistent productions of a variety of VOCs upon reaction with O3, notably isoprene, aldehydes, and ketones. Aqueous DMS is rapidly removed from the reactions with O3. To test the importance of dissolved organic matter precursors, we added increasing (milliliter) volumes of Emiliania huxleyi culture to the equilibrator filled with aged seawater, and observed significant linear increases in gas phase concentrations of a number of VOCs. Reactions between DOM and O3 at the sea-air interface represent a potentially significant source of VOCs in marine air and a sink of atmospheric O3.

  20. Volatile organic compounds emitted by filamentous fungi isolated from flooded homes after Hurricane Sandy show toxicity in a Drosophila bioassay.

    PubMed

    Zhao, G; Yin, G; Inamdar, A A; Luo, J; Zhang, N; Yang, I; Buckley, B; Bennett, J W

    2016-10-17

    Superstorm Sandy provided an opportunity to study filamentous fungi (molds) associated with winter storm damage. We collected 36 morphologically distinct fungal isolates from flooded buildings. By combining traditional morphological and cultural characters with an analysis of ITS sequences (the fungal DNA barcode), we identified 24 fungal species that belong to eight genera: Penicillium (11 species), Fusarium (four species), Aspergillus (three species), Trichoderma (two species), and one species each of Metarhizium, Mucor, Pestalotiopsis, and Umbelopsis. Then, we used a Drosophila larval assay to assess possible toxicity of volatile organic compounds (VOCs) emitted by these molds. When cultured in a shared atmosphere with growing cultures of molds isolated after Hurricane Sandy, larval toxicity ranged from 15 to 80%. VOCs from Aspergillus niger 129B were the most toxic yielding 80% mortality to Drosophila after 12 days. The VOCs from Trichoderma longibrachiatum 117, Mucor racemosus 138a, and Metarhizium anisopliae 124 were relatively non-toxigenic. A preliminary analysis of VOCs was conducted using solid-phase microextraction-gas chromatography-mass spectrometry from two of the most toxic, two of the least toxic, and two species of intermediate toxicity. The more toxic molds produced higher concentrations of 1-octen-3-ol, 3-octanone, 3-octanol, 2-octen-1-ol, and 2-nonanone; while the less toxic molds produced more 3-methyl-1-butanol and 2-methyl-1-propanol, or an overall lower amount of volatiles. Our data support the hypothesis that at certain concentrations, some VOCs emitted by indoor molds are toxigenic.

  1. Pollution characteristics of ambient volatile organic compounds (VOCs) in the southeast coastal cities of China.

    PubMed

    Tong, Lei; Liao, Xu; Chen, Jinsheng; Xiao, Hang; Xu, Lingling; Zhang, Fuwang; Niu, Zhenchuan; Yu, Jianshuan

    2013-04-01

    With the rapid urbanization, the southeast coastal cities of China are facing increasing air pollution in the past decades. Large emissions of VOCs from vehicles and petrochemical factories have contributed greatly to the local air quality deterioration. Investigating the pollution characteristics of VOCs is of great significance to the environmental risk assessment and air quality improvement. Ambient VOC samples were collected simultaneously from nine coastal cities of southeast China using the Tedlar bags, and were subsequently preprocessed and analyzed using a cryogenic preconcentrator and a gas chromatography-mass spectrometry system, respectively. VOC compositions, spatial distributions, seasonal variations and ozone formation potentials (OPFs) were discussed. Results showed that methylene chloride, toluene, isopropyl alcohol and n-hexane were most abundant species, and oxygenated compounds, aromatics and halogenated hydrocarbons were most abundant chemical classes (62.5-95.6% of TVOCs). Both industrial and vehicular exhausts might contribute greatly to the VOC emissions. The VOC levels in the southeast coastal cities of China were sufficiently high (e.g., 6.5 μg m(-3) for benzene) to pose a health risk to local people. A more serious pollution state was found in the southern cities of the study region, while higher VOC levels were usually observed in winter. The B/T ratio (0.26 ± 0.09) was lower than the typical ratio (ca. 0.6) for roadside samples, while the B/E (1.6-7.6) and T/E (7.2-26.8) ratios were higher than other cities around the world, which indicated a unique emission profile in the study region. Besides, analysis on ozone formation potentials (OFPs) indicated that toluene was the most important species in ozone production with the accountabilities for total OFPs of 22.6 to 59.6%.

  2. Method for lowering the VOCS emitted during drying of wood products

    DOEpatents

    Banerjee, Sujit; Boerner, James Robert; Su, Wei

    2000-01-01

    The present invention is directed to a method for removal of VOCs from wood products prior to drying the wood products. The method of the invention includes the steps of providing a chamber having an opening for receiving wood and loading the chamber with green wood. The wood is loaded to an extent sufficient to provide a limited headspace in the chamber. The chamber is then closed and the wood is heated in the chamber for a time and at a temperature sufficient to saturate the headspace with moisture and to substantially transfer VOCs from the wood product to the moisture in the headspace.

  3. Monitoring biogenic volatile compounds emitted by Eucalyptus citriodora using SPME.

    PubMed

    Zini, C A; Augusto, F; Christensen, T E; Smith, B P; Caramão, E B; Pawliszy, J

    2001-10-01

    A procedure to monitor BVOC emitted by living plants using SPME technique is presented. For this purpose, a glass sampling chamber was designed. This device was employed for the characterization of biogenic volatile compounds emitted by leaves of Eucalyptus citriodora. After extraction with SPME fibers coated with PDMS/ DVB, it was possible to identify or detect 33 compounds emitted by this plant. A semiquantitative approach was applied to monitor the behavior of the emitted BVOC during 9 days. Circadian profiles of the variation in the concentration of isoprene were plotted. Using diffusion-based SPME quantitation, a recently introduced analytical approach, with extraction times as short as 15 s, it was possible to quantify subparts-per-billion amounts of isoprene emitted by this plant.

  4. Cellular reactions to long-term volatile organic compound (VOC) exposures

    PubMed Central

    Gostner, Johanna M.; Zeisler, Johannes; Alam, Mohammad Tauqeer; Gruber, Peter; Fuchs, Dietmar; Becker, Kathrin; Neubert, Kerstin; Kleinhappl, Markus; Martini, Stefan; Überall, Florian

    2016-01-01

    Investigations of cellular processes initiated by volatile organic compounds (VOCs) are limited when modelling realistic long-term exposure scenarios at low concentrations. Exposure to indoor VOCs is associated with a range of adverse effects, but data on molecular changes at regulatory threshold limits are lacking. Activity analysis of VOC in vitro can be a valuable complement to inhalation toxicological evaluations. We developed an exposure platform that generates a stable VOC atmosphere and allows the exposure of cells for longer periods. Using formaldehyde as a model analyte, air-liquid interface cultured A549 lung epithelial cells were exposed to critical concentrations of 0.1 and 0.5 ppm for 3 days. Owing to the lack of known exposure biomarkers, we applied a genome-wide transcriptional analysis to investigate cellular responses at these sublethal concentrations. We demonstrate a minor overlap of differentially expressed transcripts for both treatment concentrations, which can be further analyzed for their use as exposure biomarkers. Moreover, distinct expression patterns emerge for 0.1 and 0.5 ppm formaldehyde exposure, which is reflected in significant enrichment of distinct biological processes. More specifically, metabolism of specific compound classes, lipid biosynthesis and lung-associated functions are affected by lower exposure levels and processes affecting proliferation and apoptosis dominate the higher exposure levels. PMID:27905399

  5. Volatile organic compounds (VOCs) in photochemically aged air from the eastern and western Mediterranean

    NASA Astrophysics Data System (ADS)

    Derstroff, Bettina; Hüser, Imke; Bourtsoukidis, Efstratios; Crowley, John N.; Fischer, Horst; Gromov, Sergey; Harder, Hartwig; Janssen, Ruud H. H.; Kesselmeier, Jürgen; Lelieveld, Jos; Mallik, Chinmay; Martinez, Monica; Novelli, Anna; Parchatka, Uwe; Phillips, Gavin J.; Sander, Rolf; Sauvage, Carina; Schuladen, Jan; Stönner, Christof; Tomsche, Laura; Williams, Jonathan

    2017-08-01

    During the summertime CYPHEX campaign (CYprus PHotochemical EXperiment 2014) in the eastern Mediterranean, multiple volatile organic compounds (VOCs) were measured from a 650 m hilltop site in western Cyprus (34° 57' N/32° 23' E). Periodic shifts in the northerly Etesian winds resulted in the site being alternately impacted by photochemically processed emissions from western (Spain, France, Italy) and eastern (Turkey, Greece) Europe. Furthermore, the site was situated within the residual layer/free troposphere during some nights which were characterized by high ozone and low relative humidity levels. In this study we examine the temporal variation of VOCs at the site. The sparse Mediterranean scrub vegetation generated diel cycles in the reactive biogenic hydrocarbon isoprene, from very low values at night to a diurnal median level of 80-100 pptv. In contrast, the oxygenated volatile organic compounds (OVOCs) methanol and acetone exhibited weak diel cycles and were approximately an order of magnitude higher in mixing ratio (ca. 2.5-3 ppbv median level by day, range: ca. 1-8 ppbv) than the locally emitted isoprene and aromatic compounds such as benzene and toluene. Acetic acid was present at mixing ratios between 0.05 and 4 ppbv with a median level of ca. 1.2 ppbv during the daytime. When data points directly affected by the residual layer/free troposphere were excluded, the acid followed a pronounced diel cycle, which was influenced by various local effects including photochemical production and loss, direct emission, dry deposition and scavenging from advecting air in fog banks. The Lagrangian model FLEXPART was used to determine transport patterns and photochemical processing times (between 12 h and several days) of air masses originating from eastern and western Europe. Ozone and many OVOC levels were ˜ 20 and ˜ 30-60 % higher, respectively, in air arriving from the east. Using the FLEXPART calculated transport time, the contribution of photochemical

  6. 40 CFR Table 1 to Subpart B of... - Volatile Organic Compound (VOC) Content Limits for Automobile Refinish Coatings

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Limits for Automobile Refinish Coatings 1 Table 1 to Subpart B of Part 59 Protection of Environment... Automobile Refinish Coatings Pt. 59, Subpt. B, Table 1 Table 1 to Subpart B of Part 59—Volatile Organic Compound (VOC) Content Limits for Automobile Refinish Coatings Coating category Grams VOC per liter...

  7. Characterization of Volatile Organic Compound (VOC) Emissions at Sites of Oil Sands Extraction and Upgrading in northern Alberta

    NASA Astrophysics Data System (ADS)

    Marrero, J.; Simpson, I. J.; Meinardi, S.; Blake, D. R.

    2011-12-01

    The crude oil reserves in Canada's oil sands are second only to Saudi Arabia, holding roughly 173 billion barrels of oil in the form of bitumen, an unconventional crude oil which does not flow and cannot be pumped without heating or dilution. Oil sands deposits are ultimately used to make the same petroleum products as conventional forms of crude oil, though more processing is required. Hydrocarbons are the basis of oil, coal and natural gas and are an important class of gases emitted into the atmosphere during oil production, particularly because of their effects on air quality and human health. However, they have only recently begun to be independently assessed in the oil sands regions. As part of the 2008 ARCTAS airborne mission, whole air samples were collected in the boundary layer above the surface mining operations of northern Alberta. Gas chromatography analysis revealed enhanced concentrations of 53 VOCs (C2 to C10) over the mining region. When compared to local background levels, the measured concentrations were enhanced up to 1.1-400 times for these compounds. To more fully characterize emissions, ground-based studies were conducted in summer 2010 and winter 2011 in the oil sands mining and upgrading areas. The data from the 200 ground-based samples revealed enhancements in the concentration of 65 VOCs. These compounds were elevated up to 1.1-3000 times above background concentrations and include C2-C8 alkanes, C1-C5 alkyl nitrates, C2-C4 alkenes and potentially toxic aromatic compounds such as benzene, toluene, and xylenes.

  8. Diagnosis of air quality through observation and modeling of volatile organic compounds (VOCs) as pollution tracers

    NASA Astrophysics Data System (ADS)

    Liu, Wen-Tzu; Hsieh, Hsin-Cheng; Chen, Sheng-Po; Chang, Julius S.; Lin, Neng-Huei; Chang, Chih-Chung; Wang, Jia-Lin

    2012-08-01

    This study used selected ambient volatile organic compounds (VOCs) as pollution tracers to study the effects of meteorology on air quality. A remote coastal site was chosen as a receptor to monitor pollutants transported upwind from urban traffic and industrial sources. Large concentration variability in VOC concentrations was observed at the coastal site due to rapid changes in meteorology, which caused periodic land-sea exchange of air masses. To assure the quality of the on-line measurements, uniform concentrations of chlorofluorocarbon-113 (CFC-113) were exploited as an internal check of the instrument's stability and the resulting data quality. A VOC speciated air quality model was employed to simulate both temporal and spatial distributions of VOC plumes. The model successfully captured the general features of the variations of toluene as a pollution tracer, which suggests that emissions and meteorology were reasonably well simulated in the model. Through validation by observation, the model can display both the temporal and spatial distribution of air pollutants in a dynamic manner. Thus, a more insightful understanding of how local air quality is affected by meteorology can be obtained.

  9. Investigation of transpiration and/or accumulation of volatile organic compounds (VOCs) by plants

    SciTech Connect

    Goodrich, R.L.; Carlsen, T.M.

    1994-12-31

    The authors are in the planning stages of an investigation to explore plant transpiration and/or accumulation of VOCs (primarily Trichloroethylene [TCE]) by native vegetation. Such processes may naturally remediate these compounds in shallow ground water. To adequately quantify the amount of TCE in ground water prior to vegetation uptake, the authors will first install shallow piezometers adjacent to existing vegetation. Vegetation sampling will be synchronized with the ground water sampling to establish baseline conditions. They will conduct a literature search to identify potential structures with high lipid content in the plant species of interest (Populus fremontii, Typha latifolia and Salix). To investigate VOC distribution in the plant, individual morphological segments of the plant will be analyzed. The vegetation will be dissected into distinct segments, such as the vegetative (stem and leaves) and reproductive structures, to determine the possible accumulation of TCE at various points within the plant. They have completed preliminary development of analytical methods that they will use to analyze the samples. In the field, plastic (Tedlar) bags will be tightly secured onto the vegetation and a direct head-space analysis will be conducted on the bags, thus providing information on the rate of transpiration compared to the actual accumulation of VOCs within the plant. At a minimum, they expect to document VOC losses from the ground water via plant transpiration.

  10. Personal volatile organic compound (VOC) exposure of children attending elementary schools adjacent to industrial complex

    NASA Astrophysics Data System (ADS)

    Park, Kun-Ho; Jo, Wan-Kuen

    The major deficiency in linking the effects of environmental exposure to children's health is the lack of data on the exposure of children to hazardous environmental pollutants. Accordingly, the present study compared the personal volatile organic compound (VOC) exposure of children from four elementary schools at different proximities to the Daegu Dyeing Industrial Complex (DDIC) and adjacent to different traffic densities. The personal air concentrations of four VOCs (toluene, m, p-xylenes, and o-xylene) were significantly higher for the children attending the school (S1) closest to the boundary of the DDIC compared to the children attending the school (S2) further away. The DDIC was the likely primary cause for the elevated personal air concentrations of the four VOCs in the children attending the school nearest the DDIC. The personal exposure to toluene and methyl tertiary-butyl ether (MTBE) for the children attending the school near a major roadway with a high traffic density was significantly higher than that for the children attending the school near a roadway with a low traffic density. The difference in the breath concentrations was generally similar to the difference in the personal air concentrations among the children from the four schools. In contrast to the children attending schools in low-income areas, the children attending schools in high-income areas exhibited no significant difference in the concentrations of any of the target VOCs in the personal air and breath samples between the children living with and without a smoker in the home.

  11. The scent fingerprint of hepatocarcinoma: in-vitro metastasis prediction with volatile organic compounds (VOCs).

    PubMed

    Amal, Haitham; Ding, Lu; Liu, Bin-bin; Tisch, Ulrike; Xu, Zhen-qin; Shi, Da-you; Zhao, Yan; Chen, Jie; Sun, Rui-xia; Liu, Hu; Ye, Sheng-Long; Tang, Zhao-you; Haick, Hossam

    2012-01-01

    Hepatocellular carcinoma (HCC) is a common and aggressive form of cancer. Due to a high rate of postoperative recurrence, the prognosis for HCC is poor. Subclinical metastasis is the major cause of tumor recurrence and patient mortality. Currently, there is no reliable prognostic method of invasion. To investigate the feasibility of fingerprints of volatile organic compounds (VOCs) for the in-vitro prediction of metastasis. Headspace gases were collected from 36 cell cultures (HCC with high and low metastatic potential and normal cells) and analyzed using nanomaterial-based sensors. Predictive models were built by employing discriminant factor analysis pattern recognition, and the classification success was determined using leave-one-out cross-validation. The chemical composition of each headspace sample was studied using gas chromatography coupled with mass spectrometry (GC-MS). Excellent discrimination was achieved using the nanomaterial-based sensors between (i) all HCC and normal controls; (ii) low metastatic HCC and normal controls; (iii) high metastatic HCC and normal controls; and (iv) high and low HCC. Several HCC-related VOCs that could be associated with biochemical cellular processes were identified through GC-MS analysis. The presented results constitute a proof-of-concept for the in-vitro prediction of the metastatic potential of HCC from VOC fingerprints using nanotechnology. Further studies on a larger number of more diverse cell cultures are needed to evaluate the robustness of the VOC patterns. These findings could benefit the development of a fast and potentially inexpensive laboratory test for subclinical HCC metastasis.

  12. Belowground communication: impacts of volatile organic compounds (VOCs) from soil fungi on other soil-inhabiting organisms.

    PubMed

    Werner, Stephanie; Polle, Andrea; Brinkmann, Nicole

    2016-10-01

    We reviewed the impact of fungal volatile organic compounds (VOCs) on soil-inhabiting organisms and their physiological and molecular consequences for their targets. Because fungi can only move by growth to distinct directions, a main mechanism to protect themselves from enemies or to manipulate their surroundings is the secretion of exudates or VOCs. The importance of VOCs in this regard has been significantly underestimated. VOCs not only can be means of communication, but also signals that are able to specifically manipulate the recipient. VOCs can reprogram root architecture of symbiotic partner plants or increase plant growth leading to enlarged colonization surfaces. VOCs are also able to enhance plant resistance against pathogens by activating phytohormone-dependent signaling pathways. In some cases, they were phytotoxic. Because the response was specific to distinct species, fungal VOCs may contribute to regulate the competition of plant communities. Additionally, VOCs are used by the producing fungus to attack rivaling fungi or bacteria, thereby protecting the emitter or its nutrient sources. In addition, animals, like springtails, nematodes, and earthworms, which are important components of the soil food web, respond to fungal VOCs. Some VOCs are effective repellents for nematodes and, therefore, have applications as biocontrol agents. In conclusion, this review shows that fungal VOCs have a huge impact on soil fauna and flora, but the underlying mechanisms, how VOCs are perceived by the recipients, how they manipulate their targets and the resulting ecological consequences of VOCs in inter-kingdom signaling is only partly understood. These knowledge gaps are left to be filled by future studies.

  13. Identification of Volatile Organic Compounds (VOCs) From Photochemical Activity in Snow Samples

    NASA Astrophysics Data System (ADS)

    Kos, G.; Ariya, P. A.

    2004-05-01

    The occurrence of VOCs in snow has been observed and can be related to anthropogenic emissions and biological activity. Photochemistry and microorganisms play a major role in the transformation of compounds in different compartments of the global ecosystem. Studies so far focused on the determination of single analytes or a class of compounds - mainly of anthropogenic origin (e.g. halogenated aromatic hydrocarbons) - that were considered important with regard to health and environmental concerns. Broader studies that describe a range of different compounds with different functionalities are relatively rare, especially for those of biological origin. The presented study investigated the formation of VOCs in snow samples and their connection with microbiological activity. The main aim was to pre-concentrate, identify and quantify volatile organic compounds. Snow samples were collected in an urban environment (Montreal, Canada) with sterilized containers. Samples were transferred into a heated reaction flask, where the sample was melted. A two-trap system was employed for pre-concentration: The first trap was used for water removal. The second trap was used for the collection of expected analytes by removing volatiles from the circulating air. Circulation was maintained with a pump at atmospheric pressure. Adsorption to glass walls of the reaction flask was prevented with halocarbon wax coating. Different sterilization methods were employed to suppress microbiological activity in order to collect background data and identify compounds of biological origin. VOC concentration and compound identification was performed with gas chromatography and mass spectrometric detection (GC-MS) by taking a sample with a gas-tight syringe through a septum-port. The sample was directly injected into the GC system. Compounds were identified by their respective mass spectra and included aldehydes and alcohols.

  14. New device for time-averaged measurement of volatile organic compounds (VOCs).

    PubMed

    Santiago Sánchez, Noemí; Tejada Alarcón, Sergio; Tortajada Santonja, Rafael; Llorca-Pórcel, Julio

    2014-07-01

    Contamination by volatile organic compounds (VOCs) in the environment is an increasing concern since these compounds are harmful to ecosystems and even to human health. Actually, many of them are considered toxic and/or carcinogenic. The main sources of pollution come from very diffuse focal points such as industrial discharges, urban water and accidental spills as these compounds may be present in many products and processes (i.e., paints, fuels, petroleum products, raw materials, solvents, etc.) making their control difficult. The presence of these compounds in groundwater, influenced by discharges, leachate or effluents of WWTPs is especially problematic. In recent years, law has been increasingly restrictive with the emissions of these compounds. From an environmental point of view, the European Water Framework Directive (2000/60/EC) sets out some VOCs as priority substances. This binding directive sets guidelines to control compounds such as benzene, chloroform, and carbon tetrachloride to be at a very low level of concentration and with a very high frequency of analysis. The presence of VOCs in the various effluents is often highly variable and discontinuous since it depends on the variability of the sources of contamination. Therefore, in order to have complete information of the presence of these contaminants and to effectively take preventive measures, it is important to continuously control, requiring the development of new devices which obtain average concentrations over time. As of today, due to technical limitations, there are no devices on the market that allow continuous sampling of these compounds in an efficient way and to facilitate sufficient detection limits to meet the legal requirements which are capable of detecting very sporadic and of short duration discharges. LABAQUA has developed a device which consists of a small peristaltic pump controlled by an electronic board that governs its operation by pre-programming. A constant flow passes

  15. Exposure of Jeepney Drivers in Manila, Philippines, to Selected Volatile Organic Compounds (VOCs)

    PubMed Central

    LUNGU, Claudiu T.

    2013-01-01

    The objective of this study was to assess the occupational exposure of jeepney drivers to selected volatile organic compounds (VOCs) in Manila, Philippines. Personal sampling was conducted on 15 jeepney drivers. Area sampling was conducted to determine the background VOC concentration in Manila as compared to that in a rural area. Both personal and area samples were collected for 5 working days. Samples were obtained using diffusive samplers and were analyzed for 6 VOCs (benzene, toluene, ethylbenzene, m,p-xylene and o-xylene) using gas chromatography. Results showed that the average personal exposure concentration of jeepney drivers was 55.6 (± 9.3), 196.6 (± 75.0), 17.9 (± 9.0), 72.5 (± 21.1) and 88.5 (± 26.5) μg/m3 for benzene, toluene, ethylbenzene, m,p-xylene and o-xylene, respectively. The urban ambient concentration was 11.8 (± 2.2), 83.7 (± 40.5) and 38.0 (± 12.1) μg/m3 for benzene, toluene and o-xylene, respectively. The rural ambient concentration was 14.0 (± 6.0) and 24.7 (± 11.9) μg/m3 for toluene and o-xylene, respectively. The personal samples had significantly higher (p<0.05) concentrations for all selected VOCs than the urban area samples. Among the area samples, the urban concentrations of benzene and toluene were significantly higher (p<0.05) than the rural concentrations. The personal exposures for all the target VOCs were not significantly different among the jeepney drivers. PMID:19218755

  16. [Pollution characteristics and health risk assessment of atmospheric volatile organic compounds (VOCs) in pesticide factory].

    PubMed

    Tan, Bing; Wang, Tie-Yu; Pang, Bo; Zhu, Zhao-Yun; Wang, Dao-Han; Lü, Yong-Long

    2013-12-01

    A method for determining volatile organic compounds (VOCs) in air by summa canister collecting and gas chromatography/ mass spectroscopy detecting was adopted. Pollution condition and characteristics of VOCs were discussed in three representative pesticide factories in Zhangjiakou City, Hebei Province. Meanwhile, an internationally recognized four-step evaluation model of health risk assessment was applied to preliminarily assess the health risk caused by atmospheric VOCs in different exposure ways, inhalation and dermal exposure. Results showed that serious total VOCs pollution existed in all factories. Concentrations of n-hexane (6161.90-6910.00 microg x m(-3)), benzene (126.00-179.30 microg x m(-3)) and 1,3-butadiene (115.00-177.30 microg x m(-3)) exceeded the Chronic Inhalation Reference Concentrations recommended by USEPA, corresponding to 700, 30 and 2 microg x m(-3), respectively. Concentration of dichloromethane (724.00 microg x m(-3)) in factory B was also higher than the reference concentration (600 microg x m(-3)). Results of health risk assessment indicated that non-carcinogenic risk indexes of VOCs ranged from 1.00E-04 to 1.00E + 00 by inhalation exposure, and 1.00E-09 to 1.00E-05 by dermal exposure. Risk indexes of n-hexane and dichloromethane by inhalation exposure in all factories exceeded 1, and risk index of benzene by inhalation in factory B was also higher than 1. Carcinogenic risk indexes exposed to VOCs ranged from 1.00E-08 to 1.00E-03 by inhalation exposure and 1. oo00E -13 to 1.00E-08 by dermal exposure. Cancer risk of 1,3-butadiene by inhalation exceeded 1.0E-04, which lead to definite risk, and those of benzene by inhalation also exceeded the maximum allowable level recommended by International Commission on Radiological Protection (5.0E-05). The risks of dermal exposure presented the same trend as inhalation exposure, but the level was much lower than that of inhalation exposure. Thus, inhalation exposure of atmospheric VOCs was the

  17. Biomass burning contribution to ambient volatile organic compounds (VOCs) in the Chengdu-Chongqing Region (CCR), China

    NASA Astrophysics Data System (ADS)

    Li, Lingyu; Chen, Yuan; Zeng, Limin; Shao, Min; Xie, Shaodong; Chen, Wentai; Lu, Sihua; Wu, Yusheng; Cao, Wei

    2014-12-01

    Ambient volatile organic compounds (VOCs) were measured intensively using an online gas chromatography-mass spectrometry/flame ionization detector (GC-MS/FID) at Ziyang in the Chengdu-Chongqing Region (CCR) from 6 December 2012 to 4 January 2013. Alkanes contributed the most (59%) to mixing ratios of measured non-methane hydrocarbons (NMHCs), while aromatics contributed the least (7%). Methanol was the most abundant oxygenated VOC (OVOC), contributing 42% to the total amount of OVOCs. Significantly elevated VOC levels occurred during three pollution events, but the chemical composition of VOCs did not differ between polluted and clean days. The OH loss rates of VOCs were calculated to estimate their chemical reactivity. Alkenes played a predominant role in VOC reactivity, among which ethylene and propene were the largest contributors; the contributions of formaldehyde and acetaldehyde were also considerable. Biomass burning had a significant influence on ambient VOCs during our study. We chose acetonitrile as a tracer and used enhancement ratio to estimate the contribution of biomass burning to ambient VOCs. Biomass burning contributed 9.4%-36.8% to the mixing ratios of selected VOC species, and contributed most (>30% each) to aromatics, formaldehyde, and acetaldehyde.

  18. Volatile organic compounds (VOCs) in urban air: How chemistry affects the interpretation of positive matrix factorization (PMF) analysis

    NASA Astrophysics Data System (ADS)

    Yuan, Bin; Shao, Min; de Gouw, Joost; Parrish, David D.; Lu, Sihua; Wang, Ming; Zeng, Limin; Zhang, Qian; Song, Yu; Zhang, Jianbo; Hu, Min

    2012-12-01

    Volatile organic compounds (VOCs) were measured online at an urban site in Beijing in August-September 2010. Diurnal variations of various VOC species indicate that VOCs concentrations were influenced by photochemical removal with OH radicals for reactive species and secondary formation for oxygenated VOCs (OVOCs). A photochemical age-based parameterization method was applied to characterize VOCs chemistry. A large part of the variability in concentrations of both hydrocarbons and OVOCs was explained by this method. The determined emission ratios of hydrocarbons to acetylene agreed within a factor of two between 2005 and 2010 measurements. However, large differences were found for emission ratios of some alkanes and C8 aromatics between Beijing and northeastern United States secondary formation from anthropogenic VOCs generally contributed higher percentages to concentrations of reactive aldehydes than those of inert ketones and alcohols. Anthropogenic primary emissions accounted for the majority of ketones and alcohols concentrations. Positive matrix factorization (PMF) was also used to identify emission sources from this VOCs data set. The four resolved factors were three anthropogenic factors and a biogenic factor. However, the anthropogenic factors are attributed here to a common source at different stages of photochemical processing rather than three independent sources. Anthropogenic and biogenic sources of VOCs concentrations were not separated completely in PMF. This study indicates that photochemistry of VOCs in the atmosphere complicates the information about separated sources that can be extracted from PMF and the influence of photochemical processing must be carefully considered in the interpretation of source apportionment studies based upon PMF.

  19. Development of a portable instrument for the continuous analysis of volatile organic compounds (VOCs) and its application to environmental monitoring.

    PubMed

    Yamada, Etsu; Matsushita, Kazumasa; Nakamura, Mitsuaki; Fuse, Yasuro; Miki, Sadao; Fujimoto, Kiyoomi; Morita, Hiroyoshi; Shimada, Osamu

    2006-01-01

    A small, time efficient and sensitive instrument for the continuous analysis of very volatile organic compounds (VOCs) with a boiling point lower than 100 degrees C in addition to the analysis of VOCs with a boiling point in the range of 100-150 degrees C was developed and applied to the measurement of VOCs in the course of university research and environmental monitoring. VOCs, such as n-hexane, acetone, ethyl acetate, alcohols, benzene, toluene and xylene, were continuously measured once every 30 min. The detection limits of hexane, ethyl acetate, benzene and toluene at a preconcentration time of 10 min were 0.41 microg/m(3) (0.12 ppb), 0.67 microg/m(3) (0.19 ppb), 0.22 microg/m(3) (0.07 ppb) and 0.22 microg/m(3) (0.06 ppb), respectively. The relative standard deviations of VOCs were less than 5%. The sensitivities of the present method VOCs were higher than those of the conventional method. The temporal changes in VOC concentrations in several laboratories and at a plant for the disposal of organic liquid wastes were measured, and the behavior of VOCs was analyzed. All the VOC concentrations, except that of ethyl acetate, determined using the portable instrument were slightly lower than those determined using a passive sampler. The portable instrument developed in the course of this study can be used for the risk assessment and management of chemicals.

  20. Distribution of volatile organic compounds (VOCs) in surface water, soil, and groundwater within a chemical industry park in Eastern China.

    PubMed

    Liu, Benhua; Chen, Liang; Huang, Linxian; Wang, Yongseng; Li, Yuehua

    2015-01-01

    This paper focuses on the distribution of volatile organic compounds (VOCs) in the surface water, soil, and groundwater within a chemical industry park in Eastern China. At least one VOC was detected in each of the 20 sampling sites, and the maximum number of VOCs detected in the surface water, groundwater, and soil were 13, 16, and 14, respectively. Two of the 10 VOCs with elevated concentrations detected in surface water, groundwater, and soil were chloroform and 1,2-dichloroethane. The characteristics of VOCs, which include volatility, boiling point, and solubility, could significantly affect their distribution in surface water, soil, and groundwater. However, due to the direct discharging of chemical industry wastewater into surface water, higher concentrations of VOCs (except chloroform) were detected in surface water than in soil and groundwater. Fortunately, the higher volatility of VOCs prevents the VOCs from impacting groundwater, which helps to maintain a lower concentration of VOCs in the groundwater than in both surface water and soil. This is because pollutants with relatively higher boiling points and lower solubilities have higher detection frequencies in soil, and contaminants with relatively lower boiling points and higher solubilities have higher detection frequencies in water, notably in surface water.

  1. Behavior of VOCs and carbonyl compounds emission from different types of wallpapers in Korea.

    PubMed

    Lim, Jungyun; Kim, Suejin; Kim, Arong; Lee, Wooseok; Han, Jinseok; Cha, Jun-Seok

    2014-04-17

    Emissions of volatile organic compounds (VOCs) and carbonyls from three types of commercially available wallpapers (i.e., PVC-coated, paper-backed, natural material-coated) in Korea were evaluated using a 20 L small chamber. A total of 332 products were tested for emission factors, frequencies of occurrence and composition ratios. Toluene and formaldehyde concentrations were below Korean standard values for all products; however, the total VOC (TVOC) concentrations exceeded current standards (4.0 mg/m²·h) for 30 products. The TVOC emission factor for PVC-coated wallpapers, for which polymer materials are used in the manufacturing process, was seven and 16 times higher than those of paper-backed and natural material-coated wallpapers, respectively. The detection frequencies for toluene and formaldehyde were the highest (82.5%) and fourth highest (79.5%), respectively among the 50 target chemical species. The composition ratios for BTEX ranged from 0.3% to 5.1% and unidentified VOCs, which were not qualitatively analyzed using standard gas methods, ranged from 90.2% to 94.8%. Among six carbonyl compounds (acrolein was not detected in any type of wallpaper), acetone had the highest concentrations in PVC-coated (44.6%) and paper-backed (66.6%) wallpapers. Formaldehyde emissions were highest (64.6%) for natural material-coated wallpapers, a result of the formaldehyde-based resin used in the manufacturing process for these products.

  2. Behavior of VOCs and Carbonyl Compounds Emission from Different Types of Wallpapers in Korea

    PubMed Central

    Lim, Jungyun; Kim, Suejin; Kim, ARong; Lee, Wooseok; Han, Jinseok; Cha, Jun-Seok

    2014-01-01

    Emissions of volatile organic compounds (VOCs) and carbonyls from three types of commercially available wallpapers (i.e., PVC-coated, paper-backed, natural material-coated) in Korea were evaluated using a 20 L small chamber. A total of 332 products were tested for emission factors, frequencies of occurrence and composition ratios. Toluene and formaldehyde concentrations were below Korean standard values for all products; however, the total VOC (TVOC) concentrations exceeded current standards (4.0 mg/m2·h) for 30 products. The TVOC emission factor for PVC-coated wallpapers, for which polymer materials are used in the manufacturing process, was seven and 16 times higher than those of paper-backed and natural material-coated wallpapers, respectively. The detection frequencies for toluene and formaldehyde were the highest (82.5%) and fourth highest (79.5%), respectively among the 50 target chemical species. The composition ratios for BTEX ranged from 0.3% to 5.1% and unidentified VOCs, which were not qualitatively analyzed using standard gas methods, ranged from 90.2% to 94.8%. Among six carbonyl compounds (acrolein was not detected in any type of wallpaper), acetone had the highest concentrations in PVC-coated (44.6%) and paper-backed (66.6%) wallpapers. Formaldehyde emissions were highest (64.6%) for natural material-coated wallpapers, a result of the formaldehyde-based resin used in the manufacturing process for these products. PMID:24747540

  3. Regulations and research related to volatile organic compounds (VOCs): Meeting the ozone standard nationwide by 2010

    SciTech Connect

    Ponder, W.H.

    1993-07-01

    The paper gives an overview of the regulatory requiremets related to ambient ozone and discusses the related research programs of the Organics Control Branch of EPA's Air and Energy Engineering Research Laboratory (AEERL). The programs are part of AEERL's comprehensive research program to identify and demonstrate prevention and control approaches for reducing volatile organic compound (VOC) emissions. VOCs react in the atmosphere to form ozone at ground level. Failure to attain the ambient ozone standard is one of the most pressing air pollution problems in the U.S. The Clean Air Act Amendments of 1990 include stringent requirements to ensure attainment of the ozone standard in some areas as early as 1993, and attainment in all areas by 2010.

  4. A Novel Wireless Wearable Volatile Organic Compound (VOC) Monitoring Device with Disposable Sensors

    PubMed Central

    Deng, Yue; Chen, Cheng; Xian, Xiaojun; Tsow, Francis; Verma, Gaurav; McConnell, Rob; Fruin, Scott; Tao, Nongjian; Forzani, Erica S.

    2016-01-01

    A novel portable wireless volatile organic compound (VOC) monitoring device with disposable sensors is presented. The device is miniaturized, light, easy-to-use, and cost-effective. Different field tests have been carried out to identify the operational, analytical, and functional performance of the device and its sensors. The device was compared to a commercial photo-ionization detector, gas chromatography-mass spectrometry, and carbon monoxide detector. In addition, environmental operational conditions, such as barometric change, temperature change and wind conditions were also tested to evaluate the device performance. The multiple comparisons and tests indicate that the proposed VOC device is adequate to characterize personal exposure in many real-world scenarios and is applicable for personal daily use. PMID:27918484

  5. Application of horizontal spiral coil heat exchanger for volatile organic compounds (VOC) emission control.

    PubMed

    Deshpande, P M; Dawande, S D

    2013-04-01

    The petroleum products have wide range of volatility and are required to be stored in bulk. The evaporation losses are significant and it is a economic as well as environmental concern, since evaporative losses of petroleum products cause increased VOC in ambient air. Control of these losses poses a major problem for the storage tank designers. Ever rising cost of petroleum products further adds to the gravity of the problem. Condensation is one of the technologies for reducing volatile organic compounds emissions. Condensation is effected by condenser, which is basically a heat exchanger and the heat exchanger configuration plays an important role. The horizontal spiral coil heat exchanger is a promising configuration that finds an application in VOC control. This paper attempts to understand underlying causes of emissions and analyse the option of horizontal spiral coil heat exchanger as vent condenser.

  6. Technology projects for characterization--monitoring of volatile organic compounds (VOCs)

    SciTech Connect

    Junk, G.A.; Haas, W.J. Jr.

    1992-07-01

    One hundred thirty technology project titles related to the characterization of volatile organic compounds (VOCs) at an arid site are listed alphabetically by first contact person in a master compilation that includes phone numbers, addresses, keywords, and short descriptions. Separate tables are presented for 62 field-demonstrated, 36 laboratory-demonstrated, and 35 developing technology projects. The technology projects in each of these three categories are also prioritized in separate summary tables. Additional tables are presented for a number of other categorizations of the technology projects: In Situ; Fiberoptic; Mass Spectrometer; Optical Spectroscopy; Raman or SERS; Ion Mobility or Acoustic; Associated; and Commercial. Four lists of contact person names are provided so details concerning the projects that deal with sampling, and VOCs in gases, waters, and soils (sediments) can be obtained. Finally, seven wide-ranging conclusions based on observations and experiences during this work are presented.

  7. On the use of plant emitted volatile organic compounds for atmospheric chemistry simulation experiments

    NASA Astrophysics Data System (ADS)

    Kiendler-Scharr, A.; Hohaus, T.; Yu, Z.; Tillmann, R.; Kuhn, U.; Andres, S.; Kaminski, M.; Wegener, R.; Novelli, A.; Fuchs, H.; Wahner, A.

    2015-12-01

    Biogenic volatile organic compounds (BVOC) contribute to about 90% of the emitted VOC globally with isoprene being one of the most abundant BVOC (Guenther 2002). Intensive efforts in studying and understanding the impact of BVOC on atmospheric chemistry were undertaken in the recent years. However many uncertainties remain, e.g. field studies have shown that in wooded areas measured OH reactivity can often not be explained by measured BVOC and their oxidation products (e.g. Noelscher et al. 2012). This discrepancy may be explained by either a lack of understanding of BVOC sources or insufficient understanding of BVOC oxidation mechanisms. Plants emit a complex VOC mixture containing likely many compounds which have not yet been measured or identified (Goldstein and Galbally 2007). A lack of understanding BVOC sources limits bottom-up estimates of secondary products of BVOC oxidation such as SOA. Similarly, the widespread oversimplification of atmospheric chemistry in simulation experiments, using single compound or simple BVOC mixtures to study atmospheric chemistry processes limit our ability to assess air quality and climate impacts of BVOC. We will present applications of the new extension PLUS (PLant chamber Unit for Simulation) to our atmosphere simulation chamber SAPHIR. PLUS is used to produce representative BVOC mixtures from direct plant emissions. We will report on the performance and characterization of the newly developed chamber. As an exemplary application, trees typical of a Boreal forest environment were used to compare OH reactivity as directly measured by LIF to the OH reactivity calculated from BVOC measured by GC-MS and PTRMS. The comparison was performed for both, primary emissions of trees without any influence of oxidizing agents and using different oxidation schemes. For the monoterpene emitters investigated here, we show that discrepancies between measured and calculated total OH reactivity increase with increasing degree of oxidation

  8. Quantitative determination of volatile organic compounds (VOC) in milk by multiple dynamic headspace extraction and GC-MS.

    PubMed

    Ciccioli, Paolo; Brancaleoni, Enzo; Frattoni, Massimiliano; Fedele, Vincenzo; Claps, Salvatore; Signorelli, Federica

    2004-01-01

    A method for the accurate determination of volatile organic compounds (VOC) in milk samples has been developed and tested. It combines multiple dynamic headspace extraction with GC-MS. Absolute amounts of VOC in the liquid phase are obtained by determining the first order kinetic dependence of the stepwise extraction of the analytes and internal standards from the liquid matrix. Compounds released from milk were collected on a train of traps filled with different solid sorbents to cover all components having a number of carbon atoms ranging from 4 to 15. They were analysed by GC-MS after thermal desorption of VOC from the collecting traps. Quantification of VOC in milk was performed using deuterated compounds as internal standards. The method was used to follow seasonal variations of monoterpenes in goat milk and to detect the impact of air pollution on the quality of milk.

  9. Predicted concentrations in new relocatable classrooms of volatile organic compounds emitted from standard and alternate interior finish materials

    SciTech Connect

    Hodgson, Alfred T.; Fisk, William J.; Shendell, Derek G.; Apte, Michael G.

    2001-07-01

    Relocatable classrooms (RCs) are widely employed by California school districts to satisfy rapidly expanding space requirements due to population growth and class size reduction policies. There is public concern regarding indoor environmental quality (IEQ) in schools, particularly in RCs, but very little data to support or dispel these concerns. Several studies are investigating various aspects of IEQ in California schools. This laboratory-based study focused on evaluating the emissions of toxic and/or odorous volatile organic compounds (VOCs), including formaldehyde and acetaldehyde, from materials used to finish the interiors of new RCs. Furthermore, the study implemented a procedure for VOC source reduction by testing and selecting lower-emitting materials as substitutes for standard materials. In total, 17 standard and alternate floor coverings, wall panels and ceiling panels were quantitatively tested for emissions of VOCs using smallscale environmental chambers. Working with the largest northern California manufacturer of conventional RCs and two school districts, specifications were developed for four new RCs to be produced in early summer 2001. Two of these will be predominantly finished with standard materials. Alternate carpet systems, an alternate wall panel covering and an alternate ceiling panel were selected for the two other RCs based on the results of the laboratory study and considerations of cost and anticipated performance and maintenance. Particular emphasis was placed on reducing the concentrations of VOCs on California agency lists of toxic compounds. Indoor concentrations of toxic and odorous VOCs were estimated for the four classrooms by mass balance using the measured VOC emission factors, exposed surface areas of the materials in the RCs, and three ventilation rate scenarios. Results indicate that reductions in the concentrations of formaldehyde, acetaldehyde phenol, di(ethylene glycol) butyl ether, vinyl acetate, 1,2,4-trimethylbenzene

  10. Seasonal variability and source apportionment of volatile organic compounds (VOCs) in the Paris megacity (France)

    NASA Astrophysics Data System (ADS)

    Baudic, Alexia; Gros, Valérie; Sauvage, Stéphane; Locoge, Nadine; Sanchez, Olivier; Sarda-Estève, Roland; Kalogridis, Cerise; Petit, Jean-Eudes; Bonnaire, Nicolas; Baisnée, Dominique; Favez, Olivier; Albinet, Alexandre; Sciare, Jean; Bonsang, Bernard

    2016-09-01

    Within the framework of air quality studies at the megacity scale, highly time-resolved volatile organic compound (C2-C8) measurements were performed in downtown Paris (urban background sites) from January to November 2010. This unique dataset included non-methane hydrocarbons (NMHCs) and aromatic/oxygenated species (OVOCs) measured by a GC-FID (gas chromatograph with a flame ionization detector) and a PTR-MS (proton transfer reaction - mass spectrometer), respectively. This study presents the seasonal variability of atmospheric VOCs being monitored in the French megacity and their various associated emission sources. Clear seasonal and diurnal patterns differed from one VOC to another as the result of their different origins and the influence of environmental parameters (solar radiation, temperature). Source apportionment (SA) was comprehensively conducted using a multivariate mathematical receptor modeling. The United States Environmental Protection Agency's positive matrix factorization tool (US EPA, PMF) was used to apportion and quantify ambient VOC concentrations into six different sources. The modeled source profiles were identified from near-field observations (measurements from three distinct emission sources: inside a highway tunnel, at a fireplace and from a domestic gas flue, hence with a specific focus on road traffic, wood-burning activities and natural gas emissions) and hydrocarbon profiles reported in the literature. The reconstructed VOC sources were cross validated using independent tracers such as inorganic gases (NO, NO2, CO), black carbon (BC) and meteorological data (temperature). The largest contributors to the predicted VOC concentrations were traffic-related activities (including motor vehicle exhaust, 15 % of the total mass on the annual average, and evaporative sources, 10 %), with the remaining emissions from natural gas and background (23 %), solvent use (20 %), wood-burning (18 %) and a biogenic source (15 %). An important finding of

  11. 40 CFR Table 1 to Subpart B of... - Volatile Organic Compound (VOC) Content Limits for Automobile Refinish Coatings

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 6 2013-07-01 2013-07-01 false Volatile Organic Compound (VOC) Content... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL VOLATILE ORGANIC COMPOUND EMISSION STANDARDS FOR CONSUMER AND COMMERCIAL PRODUCTS National Volatile Organic Compound Emission Standards...

  12. 40 CFR Table 1 to Subpart B of... - Volatile Organic Compound (VOC) Content Limits for Automobile Refinish Coatings

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 5 2011-07-01 2011-07-01 false Volatile Organic Compound (VOC) Content... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL VOLATILE ORGANIC COMPOUND EMISSION STANDARDS FOR CONSUMER AND COMMERCIAL PRODUCTS National Volatile Organic Compound Emission Standards...

  13. 40 CFR Table 1 to Subpart B of... - Volatile Organic Compound (VOC) Content Limits for Automobile Refinish Coatings

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 6 2012-07-01 2012-07-01 false Volatile Organic Compound (VOC) Content... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL VOLATILE ORGANIC COMPOUND EMISSION STANDARDS FOR CONSUMER AND COMMERCIAL PRODUCTS National Volatile Organic Compound Emission Standards...

  14. 40 CFR Table 1 to Subpart B of... - Volatile Organic Compound (VOC) Content Limits for Automobile Refinish Coatings

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 5 2010-07-01 2010-07-01 false Volatile Organic Compound (VOC) Content... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL VOLATILE ORGANIC COMPOUND EMISSION STANDARDS FOR CONSUMER AND COMMERCIAL PRODUCTS National Volatile Organic Compound Emission Standards...

  15. Safety Evaluation of Osun River Water Containing Heavy Metals and Volatile Organic Compounds (VOCs) in Rats.

    PubMed

    Azeez, L; Salau, A K; Adewuyi, S O; Osineye, S O; Tijani, K O; Balogun, R O

    2015-12-20

    This study evaluated the pH, heavy metals and volatile organic compounds (VOCs) in Osun river water. It also evaluated its safety in rats. Heavy metals were determined by atomic absorption spectrophotometry (AAS) while VOCs were determined by gas chromatography coupled with flame ionization detector (GC-FID). Male and female rats were exposed to Osun river water for three weeks and then sacrificed. The abundance of heavy metals in Osun river followed the trend Pb > Cd > Zn > Fe > Cr > Cu while VOCs followed the trend benzene < ethylbenzene < toluene < xylene. The concentrations of Pb, Cd and benzene were higher than the permissible limits of Standards Organization of Nigeria (SON) and World Health Organization (WHO) respectively. Rats exposed to Osun river water for three weeks had increased WBC, thiobarbituric acid reactive substances (TBARS), serum proteins and serum aminotransferases. There were also significant decreases in HCT, PLT, liver aminotransferases and liver glutathione compared to the control. These results show that the pollutants in Osun river water are capable of inducing hematological imbalance and liver cell injury. The toxicity induced in blood was sex-dependent affecting female rats more than male rats.

  16. Chlorinated volatile organic compounds (Cl-VOCs) in environment - sources, potential human health impacts, and current remediation technologies.

    PubMed

    Huang, Binbin; Lei, Chao; Wei, Chaohai; Zeng, Guangming

    2014-10-01

    Chlorinated volatile organic compounds (Cl-VOCs), including polychloromethanes, polychloroethanes and polychloroethylenes, are widely used as solvents, degreasing agents and a variety of commercial products. These compounds belong to a group of ubiquitous contaminants that can be found in contaminated soil, air and any kind of fluvial mediums such as groundwater, rivers and lakes. This review presents a summary of the research concerning the production levels and sources of Cl-VOCs, their potential impacts on human health as well as state-of-the-art remediation technologies. Important sources of Cl-VOCs principally include the emissions from industrial processes, the consumption of Cl-VOC-containing products, the disinfection process, as well as improper storage and disposal methods. Human exposure to Cl-VOCs can occur through different routes, including ingestion, inhalation and dermal contact. The toxicological impacts of these compounds have been carefully assessed, and the results demonstrate the potential associations of cancer incidence with exposure to Cl-VOCs. Most Cl-VOCs thus have been listed as priority pollutants by the Ministry of Environmental Protection (MEP) of China, Environmental Protection Agency of the U.S. (U.S. EPA) and European Commission (EC), and are under close monitor and strict control. Yet, more efforts will be put into the epidemiological studies for the risk of human exposure to Cl-VOCs and the exposure level measurements in contaminated sites in the future. State-of-the-art remediation technologies for Cl-VOCs employ non-destructive methods and destructive methods (e.g. thermal incineration, phytoremediation, biodegradation, advanced oxidation processes (AOPs) and reductive dechlorination), whose advantages, drawbacks and future developments are thoroughly discussed in the later sections. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. SUBSTRATE EFFECTS ON VOC EMISSIONS FROM A LATEX PAINT

    EPA Science Inventory

    The effects of two substrates -- a stainless steel plate and a gypsum board -- on the volatile organic compound (VOC) emissions from a latex paint were evaluated by environmental chamber tests. It was found that the amount of VOCs emitted from the painted stainless steel was 2 to...

  18. FORMULATING ULTRA-LOW-VOC WOOD FURNITURE COATINGS

    EPA Science Inventory

    The article discusses the formulation of ultra-low volatile organic compound (VOC) wood furniture coatings. The annual U.S. market for wood coatings is about 240, 000 cu m (63 million gal). In this basis, between 57 and 91 million kg (125 and 200 million lb) of VOCs are emitted i...

  19. FORMULATING ULTRA-LOW-VOC WOOD FURNITURE COATINGS

    EPA Science Inventory

    The article discusses the formulation of ultra-low volatile organic compound (VOC) wood furniture coatings. The annual U.S. market for wood coatings is about 240, 000 cu m (63 million gal). In this basis, between 57 and 91 million kg (125 and 200 million lb) of VOCs are emitted i...

  20. SUBSTRATE EFFECTS ON VOC EMISSIONS FROM A LATEX PAINT

    EPA Science Inventory

    The effects of two substrates -- a stainless steel plate and a gypsum board -- on the volatile organic compound (VOC) emissions from a latex paint were evaluated by environmental chamber tests. It was found that the amount of VOCs emitted from the painted stainless steel was 2 to...

  1. StreamVOC--A Deterministic Source-Apportionment Model to Estimate Volatile Organic Compound Concentrations in Rivers and Streams

    USGS Publications Warehouse

    Asher, William E.; Bender, David A.; Zogorski, John S.; Bartholomay, Roy C.

    2006-01-01

    This report documents the construction and verification of the model, StreamVOC, that estimates (1) the time- and position-dependent concentrations of volatile organic compounds (VOCs) in rivers and streams as well as (2) the source apportionment (SA) of those concentrations. The model considers how different types of sources and loss processes can act together to yield a given observed VOC concentration. Reasons for interest in the relative and absolute contributions of different sources to contaminant concentrations include the need to apportion: (1) the origins for an observed contamination, and (2) the associated human and ecosystem risks. For VOCs, sources of interest include the atmosphere (by absorption), as well as point and nonpoint inflows of VOC-containing water. Loss processes of interest include volatilization to the atmosphere, degradation, and outflows of VOC-containing water from the stream to local ground water. This report presents the details of StreamVOC and compares model output with measured concentrations for eight VOCs found in the Aberjona River at Winchester, Massachusetts. Input data for the model were obtained during a synoptic study of the stream system conducted July 11-13, 2001, as part of the National Water-Quality Assessment (NAWQA) Program of the U.S. Geological Survey. The input data included a variety of basic stream characteristics (for example, flows, temperature, and VOC concentrations). The StreamVOC concentration results agreed moderately well with the measured concentration data for several VOCs and provided compound-dependent SA estimates as a function of longitudinal distance down the river. For many VOCs, the quality of the agreement between the model-simulated and measured concentrations could be improved by simple adjustments of the model input parameters. In general, this study illustrated: (1) the considerable difficulty of quantifying correctly the locations and magnitudes of ground-water-related sources of

  2. TECHNICAL JUSTIFICATION FOR CHOOSING PROPANE AS A CALIBRATION AGENT FOR TOTAL FLAMMABLE VOLATILE ORGANIC COMPOUND (VOC) DETERMINATIONS

    SciTech Connect

    DOUGLAS, J.G.

    2006-07-06

    This document presents the technical justification for choosing and using propane as a calibration standard for estimating total flammable volatile organic compounds (VOCs) in an air matrix. A propane-in-nitrogen standard was selected based on a number of criteria: (1) has an analytical response similar to the VOCs of interest, (2) can be made with known accuracy and traceability, (3) is available with good purity, (4) has a matrix similar to the sample matrix, (5) is stable during storage and use, (6) is relatively non-hazardous, and (7) is a recognized standard for similar analytical applications. The Waste Retrieval Project (WRP) desires a fast, reliable, and inexpensive method for screening the flammable VOC content in the vapor-phase headspace of waste containers. Table 1 lists the flammable VOCs of interest to the WRP. The current method used to determine the VOC content of a container is to sample the container's headspace and submit the sample for gas chromatography--mass spectrometry (GC-MS) analysis. The driver for the VOC measurement requirement is safety: potentially flammable atmospheres in the waste containers must be allowed to diffuse prior to processing the container. The proposed flammable VOC screening method is to inject an aliquot of the headspace sample into an argon-doped pulsed-discharge helium ionization detector (Ar-PDHID) contained within a gas chromatograph. No actual chromatography is performed; the sample is transferred directly from a sample loop to the detector through a short, inert transfer line. The peak area resulting from the injected sample is proportional to the flammable VOC content of the sample. However, because the Ar-PDHID has different response factors for different flammable VOCs, a fundamental assumption must be made that the agent used to calibrate the detector is representative of the flammable VOCs of interest that may be in the headspace samples. At worst, we desire that calibration with the selected calibrating

  3. Influence of volatile organic compounds emitted by Pseudomonas and Serratia strains on Agrobacterium tumefaciens biofilms.

    PubMed

    Plyuta, Vladimir; Lipasova, Valentina; Popova, Alexandra; Koksharova, Olga; Kuznetsov, Alexander; Szegedi, Erno; Chernin, Leonid; Khmel, Inessa

    2016-07-01

    The ability to form biofilms plays an important role in bacteria-host interactions, including plant pathogenicity. In this work, we investigated the action of volatile organic compounds (VOCs) produced by rhizospheric strains of Pseudomonas chlororaphis 449, Pseudomonas fluorescens B-4117, Serratia plymuthica IC1270, as well as Serratia proteamaculans strain 94, isolated from spoiled meat, on biofilms formation by three strains of Agrobacterium tumefaciens which are causative agents of crown-gall disease in a wide range of plants. In dual culture assays, the pool of volatiles emitted by the tested Pseudomonas and Serratia strains suppressed the formation of biofilms of A. tumefaciens strains grown on polycarbonate membrane filters and killed Agrobacterium cells in mature biofilms. The individual VOCs produced by the tested Pseudomonas strains, that is, ketones (2-nonanone, 2-heptanone, 2-undecanone), and dimethyl disulfide (DMDS) produced by Serratia strains, were shown to kill A. tumefaciens cells in mature biofilms and suppress their formation. The data obtained in this study suggest an additional potential of some ketones and DMDS as protectors of plants against A. tumefaciens strains, whose virulence is associated with the formation of biofilms on the infected plants.

  4. Organic liquids storage tanks volatile organic compounds (VOCS) emissions dispersion and risk assessment in developing countries: the case of Dar-es-Salaam City, Tanzania.

    PubMed

    Jackson, Msafiri M

    2006-05-01

    The emission estimation of nine volatile organic compounds (VOCs) from eight organic liquids storage tanks companies in Dar-es-Salaam City Tanzania has been done by using US EPA standard regulatory storage tanks emission model (TANKS 4.9b). Total VOCs atmospheric emission has been established to be 853.20 metric tones/yr. It has been established further that petrol storage tanks contribute about 87% of total VOCs emitted, while tanks for other refined products and crude oil were emitting 10% and 3% of VOCs respectively. Of the eight sources (companies), the highest emission value from a single source was 233,222.94 kg/yr and the lowest single source emission value was 6881.87 kg/yr. The total VOCs emissions estimated for each of the eight sources were found to be higher than the standard level of 40,000 kg/yr per source for minor source according to US EPA except for two sources, which were emitting VOCs below the standard level. The annual emissions per single source for each of the VOCs were found to be below the US EPA emissions standard which is 2,000 kg/yr in all companies except the emission of hexane from company F1 which was slightly higher than the standard. The type of tanks used seems to significantly influence the emission rate. Vertical fixed roof tanks (VFRT) emit a lot more than externally floating roof tanks (EFRT) and internally floating roof tanks (IFRT). The use of IFRT and EFRT should be encouraged especially for storage of petrol which had highest atmospheric emission contribution. Model predicted atmospheric emissions are less than annual losses measured by companies in all the eight sources. It is possible that there are other routes for losses beside atmospheric emissions. It is therefore important that waste reduction efforts in these companies are directed not only to reducing atmospheric emissions, but also prevention of the spillage and leakage of stored liquid and curbing of the frequently reported illegal siphoning of stored products

  5. Spatial and temporal trends of volatile organic compounds (VOC) in a rural area of northern Spain.

    PubMed

    Parra, M A; González, L; Elustondo, D; Garrigó, J; Bermejo, R; Santamaría, J M

    2006-10-15

    Ambient concentrations of volatile organic compounds (VOCs) were measured at 40 rural sampling points in Navarre (northern Spain). Air samples were collected by means of sorbent passive sampling and analyzed by thermal desorption (TD) and gas chromatography/mass-selective detector (GC/MSD). A total of 140 VOCs were identified during the study, which was carried out between May to October 2004 for a total of a 10 biweekly sampling campaigns. Concentrations of benzene, toluene, ethylbenzene, m/p-xylenes, o-xylene (BTEX) and 1,3,5-trimethylbenzene were determined in order to investigate their temporal and spatial distributions. Geostatistical analysis pointed to traffic as the main emission source of these compounds. Supporting this idea, BTEX and nitrogen oxides concentrations were found to be highly significantly correlated (r = 0.495, P = 0.001), whereas a strong negative correlation between BTEX and ozone was also observed (r = -0.355, P = 0.025). The concentrations for the BTEX group were similar to the values that have been previously reported for other rural areas.

  6. Measurements of volatile organic compounds emitted from plants in the metropolitan area of São Paulo City , Brazil.

    NASA Astrophysics Data System (ADS)

    Carvalho, L.; Pisani, S.; Pool, C.; Vasconcellos, P.

    2003-04-01

    The presence of the biogenic hydrocarbons in an NO_x-containing atmosphere can enhance ozone generation and the impact of volatile organic compounds (VOCs) emitted from vegetation on atmospheric chemistry has been investigated. No study of VOC emission rates from plant species has been carried out in São Paulo City, Brazil, prior to this work. This study is part of a three-years project on biogenic volatile organic compounds emissions from species of plants found in the vegetation of the São Paulo metropolitan area. Typical plants (Alchornea sidifolia, Cupania oblongifolia, Cecropia pachystachia, Casearia sylvestris, Machaerium villosum, Croton floribundus, Myrcia rostrata, Solanum erianthum and Ficus insípida) were selected and identical species were studied in urban, sub-urban and forest regions. Biogenic hydrocarbons were determined placing branches of plants in enclosures and measuring the accumulation of emitted compounds in an all-Teflon chamber, the cuvette system. Measuring ambient VOC concentration adsorptive preconcentration, followed by GC-MS after thermal desorption of the sample, was employed to determine components heavier than C_5. Collection of carbonyl compounds on 2, 4-dinitrophenylhydrazine coated particles followed by HPLC-UV was used to analyze low molecular weight carbonyl compounds. Emissions rates of isoprene, a-pinene, camphene and limonene ranged from 0.01 to 2.16 μg C/h.g and emissions rates of aldehydes (C_1 - C_6), acrolein, methacrolein, 2-butanone and acetone ranged from 0.04 to 4.20 μg C/h.g. Ambient and chamber temperatures, relative humidity, light intensity, O_3 and NO_x were monitored during experiments.

  7. Cytotoxicity and genotoxicity in human lung epithelial A549 cells caused by airborne volatile organic compounds emitted from pine wood and oriented strand boards.

    PubMed

    Gminski, Richard; Tang, Tao; Mersch-Sundermann, Volker

    2010-06-16

    Due to the massive reduction of air-change rates in modern, energy-saving houses and dwellings, the contribution of volatile organic compound (VOCs) emissions from wood-based materials to indoor air quality has become increasingly important. To evaluate toxicity of VOC mixtures typically emitted from pine wood and oriented strand boards (OSB) and their main constituents (selected terpenes and aldehydes), cytotoxicity and genotoxicity were investigated in human A549 lung cells. To facilitate exposure directly via gas phase, a 250 L emission chamber was combined with a Vitrocell exposure system. VOC exposure concentrations were measured by GC/MSD. Biological effects were determined after an exposure time of 1h by measuring cytotoxicity (erythrosine B staining) and genotoxicity (comet assay). Neither cytotoxic nor genotoxic effects were observed for VOC mixtures emitted from pine wood or OSB at loading factors of approximately 13 m(2)/m(3) (worst case conditions) of the panels (with maximum VOC levels of about 80 mg/m(3)) in comparison to clean air. While alpha-pinene and Delta(3)-carene did not induce toxic effects even at exposure concentrations of up to 1800 mg/m(3) and 600 mg/m(3), respectively, hexanal showed a cytotoxic effect at 2000 mg/m(3). The alpha,beta-unsaturated aldehydes 2-heptenal and 2-octenal caused genotoxic effects in concentrations exceeding 100mg/m(3) and 40 mg/m(3), respectively. In conclusion, high concentrations of VOCs and VOC mixtures emitted from pine wood and OSB did not lead to adverse effects in A549 human lung cells even at concentrations 10(2) to 10(5)-fold higher than those found in normal indoor air. Attention must be paid to mutagenic and possibly carcinogenic alpha,beta-unsaturated aldehydes.

  8. Source apportionment of ambient volatile organic compounds (VOCs)and their characteristics in Chengdu, southwest of China

    NASA Astrophysics Data System (ADS)

    Deng, Yuanyuan; Xie, Shaodong; Li, Jing; Li, Yaqi

    2017-04-01

    Chengdu, located in the largest basin region in the world, suffers from increasing ground-level ozone and aerosol pollutions. Volatile organic compounds (VOCs) are one of the prominent precursors of ground-level ozone and aerosols. Ambient VOCs were measured continuously using an online gas chromatography-mass spectrometry/flame ionization detector (GC-MS/FID) with a time resolution of 1 hour from 28 August 2016 to 7 October 2016 at Pixian in Chengdu. 99 measurements of VOCs were conducted including 28 alkanes, 11 alkenes, 16 aromatics, 13 oxygenated VOCs (OVOCs) and 29 halocarbons, acetylene, and acetonitrile. Based on the hourly average data, positive matrix factorization (PMF) was used to better understand the emission sources of VOCs in Chengdu. The average mixing ratios of alkanes, alkenes, aromatics, OVOCs, halocarbons, acetylene, and acetonitrile were respectively 14.49 ppbv, 4.92 ppbv, 5.14 ppbv, 9.74 ppbv, 7.77 ppbv, 3.56 ppbv, and 0.43 ppbv. Six sources were extracted by using PMF model. Liquefied petroleum gas, background and petrochemical industries contributed 28%, 19%, 18% to the total ambient VOCs, respectively. Biogenic emission (14%), Gasoline vehicles (13%), Solvent use (8%) were also identified as major sources of ambient VOCs at Pixian.

  9. Emission and Chemistry of Volatile Organic Compounds (VOCs) as Observed at T3: Contrast of the Dry and Wet Seasons

    NASA Astrophysics Data System (ADS)

    Liu, Y.; McKinney, K. A.; Watson, T. B.; Springston, S. R.; Seco, R.; Park, J. H.; Kim, S.; Shilling, J. E.; Guenther, A. B.; Yee, L.; Isaacman-VanWertz, G. A.; Wernis, R. A.; Goldstein, A. H.; Brito, J.; Artaxo, P.; Souza, R. A. F. D.; Manzi, A. O.; Martin, S. T.

    2015-12-01

    Tropical rainforests are vigorous emitters of volatile organic compounds (VOCs) year round. Despite the small seasonal variation expected for tropical rainforests, converging evidence has shown that, among other factors, there can be considerable differences between the wet and dry seasons in leaf coverage, species composition, leaf-level photosynthetic photo flux, and ozone and NOx levels, which are important controlling factors of VOC emission and chemistry. There have been, however, a limited number of studies on the seasonality of VOC concentrations over tropical rainforests. As part of the GoAmazon 2014/5 Experiment, two-month continuous measurements of VOC compounds were carried out using a proton-transfer-reaction time-of-flight mass spectrometer (PTR-TOF-MS) at the T3 site in both the wet and dry seasons of 2014. During the dry season most biogenic VOC species and their oxidation products exhibited increased concentration. For some species, the diel pattern was also different between the two seasons. Implications of the seasonality of the emission and chemistry of biogenic VOCs, in particular isoprene and terpenes, are discussed.

  10. A Compendium of Volatile Organic Compounds (VOCs) Released By Human Cell Lines

    PubMed Central

    Filipiak, Wojciech; Mochalski, Pawel; Filipiak, Anna; Ager, Clemens; Cumeras, Raquel; Davis, Cristina E.; Agapiou, Agapios; Unterkofler, Karl; Troppmair, Jakob

    2016-01-01

    Volatile organic compounds (VOCs) offer unique insights into ongoing biochemical processes in healthy and diseased humans. Yet, their diagnostic use is hampered by the limited understanding of their biochemical or cellular origin and their frequently unclear link to the underlying diseases. Major advancements are expected from the analyses of human primary cells, cell lines and cultures of microorganisms. In this review, a database of 125 reliably identified VOCs previously reported for human healthy and diseased cells was assembled and their potential origin is discussed. The majority of them have also been observed in studies with other human matrices (breath, urine, saliva, feces, blood, skin emanations). Moreover, continuing improvements of qualitative and quantitative analyses, based on the recommendations of the ISO-11843 guidelines, are suggested for the necessary standardization of analytical procedures and better comparability of results. The data provided contribute to arriving at a more complete human volatilome and suggest potential volatile biomarkers for future validation. Dedication: This review is dedicated to the memory of Prof. Dr. Anton Amann, who sadly passed away on January 6, 2015. He was motivator and motor for the field of breath research. PMID:27160536

  11. Modeling emissions of volatile organic compounds from silage

    USDA-ARS?s Scientific Manuscript database

    Volatile organic compounds (VOCs), necessary reactants for photochemical smog formation, are emitted from numerous sources. Limited available data suggest that dairy farms emit VOCs with cattle feed, primarily silage, being the primary source. Process-based models of VOC transfer within and from si...

  12. The indoor volatile organic compound (VOC) characteristics and source identification in a new university campus in Tianjin, China.

    PubMed

    Kang, Jian; Liu, Junjie; Pei, Jingjing

    2017-06-01

    This study investigates the volatile organic compounds (VOCs) constituents and concentration levels on a new university campus, where all of the buildings including classrooms and student dormitories were newly built and decorated within 1 year. Investigated indoor environments include dormitories, classrooms, and the library. About 30 dormitory buildings with different furniture loading ratios were measured. The characteristics of the indoor VOCs species are analyzed and possible sources are identified. The VOCs were analyzed with gas chromatography-mass spectroscopy (GC-MS). It was found that the average total VOC (TVOC) concentration can reach 2.44 mg/m(3). Alkenes were the most abundant VOCs in dormitory rooms, contributing up to 86.5% of the total VOCs concentration. The concentration of α-pinene is the highest among the alkenes. Unlike the dormitory rooms, there is almost no room with TVOC concentration above 0.6 mg/m(3) in classroom and library buildings. Formaldehyde concentration in the dormitory rooms increased about 23.7% after the installation of furniture, and the highest level reached 0.068 mg/m(3). Ammonia released from the building antifreeze material results in an average indoor concentration of 0.28 mg/m(3), which is 100% over the threshold and should be seriously considered. Further experiments were conducted to analyze the source of the α-pinene and some alkanes in dormitory rooms. The results showed that the α-pinene mainly comes from the bed boards, while the wardrobes are the main sources of alkanes. The contribution of the pinewood bed boards to the α-pinene and TVOC concentration can reach up to above 90%. The same type rooms were sampled 1 year later and the decay rate of α-pinene is quite high, close to 100%, so that it almost cannot be detected in the sampled rooms. Analysis of indoor volatile organic compounds (VOCs) in newly built campus buildings in China identified the specific constituents of indoor VOCs contaminants exposed to

  13. First results on headspace-solid phase microextraction-gas chromatography/mass spectrometry of volatile organic compounds emitted by wax objects in museums.

    PubMed

    Lattuati-Derieux, A; Thao, S; Langlois, J; Regert, M

    2008-04-11

    Sampling volatile organic compounds (VOCs) emitted by a large variety of materials is nowadays a very useful technique for analytical purpose. In the field of cultural heritage, it can be applied to identify some constituents of museum artefacts off-gassing VOCs without sampling on the object itself. In this study, we focused on objects made of wax. First volatiles emitted by a reference beeswax were trapped and identified by headspace-solid phase microextraction (HS-SPME)-gas chromatography and mass spectrometry (GC/MS). This allowed to identify numerous volatile biomarkers, namely saturated n-alkanes from C(10) to C(21), saturated n-carboxylic acids containing 6-12 carbon atoms, benzene and cinnamic derivatives that may be considered as volatile biomarkers of beeswax. The SPME strategy was then performed at the Orsay museum (Paris) in a showcase containing a wax sculpture "Le Mineur de la Loire" by J.-J. Carriès. The use of beeswax in this sculpture was unequivocally confirmed by the VOCs concentrated in the showcase, together with a set of characteristic molecular compounds identified by HT-GC/MS. HS-SPME-GC/MS thus appears to be a powerful in situ and non-invasive analytical technique that allows to identify natural substances in the field of cultural heritage without any sampling of solid matter from the object. The results obtained are promising for orientating the strategy of preventive conservation related to works of art characterised by important emission of VOCs.

  14. Oil and Natural Gas Industry Sources Covered by the 2012 New Source Performance Standards (NSPS) for Volatile Organic Compounds (VOCs) and the 2016 NSPS for Methane and VOCs, by Site

    EPA Pesticide Factsheets

    This is a 2016 table that looks at oil and natural gas industry site types and lists the applicable rules for the 2012 and 2016 new source performance standards (NSPS) and Volatile Organic Compounds (VOC) rules.

  15. CRITICAL EVALUATION OF THE DIFFUSION HYPOTHESIS IN THE THEORY OF POROUS MEDIA VOLATILE ORGANIC COMPOUND (VOC) SOURCES AND SINKS

    EPA Science Inventory

    The paper proposes three alternative, diffusion-limited mathematical models to account for volatile organic compound (VOC) interactions with indoor sinks, using the linear isotherm model as a reference point. (NOTE: Recent reports by both the U.S. EPA and a study committee of the...

  16. Volatile Organic Compound (VOC) emissions from feedlot pen surface materials as affected by within pen location, moisture, and temperature

    USDA-ARS?s Scientific Manuscript database

    A laboratory study was conducted to evaluate the effects of pen location, moisture, and temperature on emissions of volatile organic compounds (VOC) from surface materials obtained from feedlot pens where beef cattle were fed a diet containing 30% wet distillers grain plus solubles. Surface material...

  17. Navy compliance with volatile organic compounds (VOC) regulations for marine coatings. Final report Oct-Nov 90

    SciTech Connect

    Thielen, T.

    1990-12-01

    Air-pollution regulations in California are requiring the U.S. Navy and the private sector to develop new types of coating specifications and paints to meet California air pollution regulations and volatile organic compounds (VOC) requirements. The progress made in these areas and the impact of these regulations upon Navy operations are discussed.

  18. CRITICAL EVALUATION OF THE DIFFUSION HYPOTHESIS IN THE THEORY OF POROUS MEDIA VOLATILE ORGANIC COMPOUND (VOC) SOURCES AND SINKS

    EPA Science Inventory

    The paper proposes three alternative, diffusion-limited mathematical models to account for volatile organic compound (VOC) interactions with indoor sinks, using the linear isotherm model as a reference point. (NOTE: Recent reports by both the U.S. EPA and a study committee of the...

  19. Emissions of Volatile Organic Compounds (VOCs) Associated with Natural Gas Production in the Uintah Basin, Utah

    NASA Astrophysics Data System (ADS)

    Warneke, C.; Geiger, F.; Zahn, A.; Graus, M.; De Gouw, J. A.; Gilman, J. B.; Lerner, B. M.; Roberts, J. M.; Edwards, P. M.; Dube, W. P.; Brown, S. S.; Peischl, J.; Ryerson, T. B.; Williams, E. J.; Petron, G.; Kofler, J.; Sweeney, C.; Karion, A.; Dlugokencky, E. J.

    2012-12-01

    Technological advances such as hydraulic fracturing have led to a rapid increase in the production of natural gas from several basins in the Rocky Mountain West, including the Denver-Julesburg basin in Colorado, the Uintah basin in Utah and the Upper Green River basin in Wyoming. There are significant concerns about the impact of natural gas production on the atmosphere, including (1) emissions of methane, which determine the net climate impact of this energy source, (2) emissions of reactive hydrocarbons and nitrogen oxides, and their contribution to photochemical ozone formation, and (3) emissions of air toxics with direct health effects. The Energy & Environment - Uintah Basin Wintertime Ozone Study (UBWOS) in 2012 was focused on addressing these issues. During UBWOS, measurements of volatile organic compounds (VOCs) were made using proton-transfer-reaction mass spectrometry (PTR-MS) instruments from a ground site and a mobile laboratory. Measurements at the ground site showed mixing ratios of VOCs related to oil and gas extraction were greatly enhanced in the Uintah basin, including several days long periods of elevated mixing ratios and concentrated short term plumes. Diurnal variations were observed with large mixing ratios during the night caused by low nighttime mixing heights and a shift in wind direction during the day. The mobile laboratory sampled a wide variety of individual parts of the gas production infrastructure including active gas wells and various processing plants. Included in those point sources was a new well that was sampled by the mobile laboratory 11 times within two weeks. This new well was previously hydraulically fractured and had an active flow-back pond. Very high mixing ratios of aromatics were observed close to the flow-back pond. The measurements of the mobile laboratory are used to determine the source composition of the individual point sources and those are compared to the VOC enhancement ratios observed at the ground site. The

  20. Systemic resistance induced by volatile organic compounds emitted by plant growth-promoting fungi in Arabidopsis thaliana.

    PubMed

    Naznin, Hushna Ara; Kiyohara, Daigo; Kimura, Minako; Miyazawa, Mitsuo; Shimizu, Masafumi; Hyakumachi, Mitsuro

    2014-01-01

    Volatile organic compounds (VOC) were extracted and identified from plant growth-promoting fungi (PGPF), Phoma sp., Cladosporium sp. and Ampelomyces sp., using gas chromatography-mass spectrometry (GC-MS). Among the three VOC extracted, two VOC blends (emitted from Ampelomyces sp. and Cladosporium sp.) significantly reduced disease severity in Arabidopsis plants against Pseudomonas syringae pv. tomato DC3000 (Pst). Subsequently, m-cresol and methyl benzoate (MeBA) were identified as major active volatile compounds from Ampelomyces sp. and Cladosporium sp., respectively, and found to elicit induced systemic resistance (ISR) against the pathogen. Molecular signaling for disease suppression by the VOC were investigated by treating different mutants and transgenic Arabidopsis plants impaired in salicylic acid (SA) or Jasmonic acid (JA)/ethylene (ET) signaling pathways with m-cresol and MeBA followed by challenge inoculation with Pst. Results show that the level of protection was significantly lower when JA/ET-impaired mutants were treated with MeBA, and in SA-, and JA/ET-disrupted mutants after m-cresol treatment, indicating the involvement of these signal transduction pathways in the ISR primed by the volatiles. Analysis of defense-related genes by real-time qRT-PCR showed that both the SA-and JA-signaling pathways combine in the m-cresol signaling of ISR, whereas MeBA is mainly involved in the JA-signaling pathway with partial recruitment of SA-signals. The ET-signaling pathway was not employed in ISR by the volatiles. Therefore, this study identified two novel volatile components capable of eliciting ISR that may be promising candidates in biological control strategy to protect plants from diseases.

  1. Measurement of volatile organic compounds (VOCs) in libraries and archives in Florence (Italy).

    PubMed

    Cincinelli, A; Martellini, T; Amore, A; Dei, L; Marrazza, G; Carretti, E; Belosi, F; Ravegnani, F; Leva, P

    2016-12-01

    Indoor air samples from libraries and archives in Florence, Italy, were collected and analysed for a variety of volatile organic compounds. The aim was to perform a characterisation of the indoor air quality, and try to elucidate if there are VOCs that may cause or result from the determination of the cultural heritage institutions. All compounds of interest were regularly detected, with BTEXs (Benzene, Toluene, Ethylbenzene, Xylenes) being the most abundant and followed by cyclic volatile methylsiloxanes, aldehydes, terpenes and organic acids. The prevalence and qualitative characteristics, such as concentrations, profiles and indoor/outdoor ratios of BTEXs underline the important influence of the outdoor air infiltrations on the indoor air concentrations. Acetic acid that is a substance that can oxidise books and other exposed objects was detected at concentrations ranging between 1.04 and 18.9μgm(-3), while furfural, that is a known marker of paper degradation, was constantly present at concentrations that ranged between 5.26 and 32.6μgm(-3). This work shows the importance that indoor air quality monitoring campaigns can have in order to give early warning to cultural heritage institution managers about the impact that indoor air quality can have on exposed and/or preserved objects.

  2. High-VOC biochar-effectiveness of post-treatment measures and potential health risks related to handling and storage.

    PubMed

    Buss, Wolfram; Mašek, Ondřej

    2016-10-01

    Biochar can contain volatile organic compounds (VOCs), formed and introduced during the pyrolysis process. In some pyrolysis units or under specific conditions during production, pyrolysis vapours can deposit on biochar in significant amounts resulting in high-VOC biochar. In this study, it was tested to which extent VOCs are released from such high-VOC biochars when openly stored, which post-treatment measures are most effective in reducing phytotoxic potential and whether the VOC emissions could exceed human health-related threshold values. It was shown that the initial VOC release of high-VOC biochars can exceed occupational exposure limit values and even after 2 months, the biochars still emitted VOCs exceeding air quality guideline values. Consequently, these specific high-VOC biochars pose health risks when handled or stored openly. Simple open-air storage turned out to be insufficient for VOC removal. Low temperature treatment, on the other hand, removed VOCs from the high-VOC biochars effectively and alleviated any human health risks and phytotoxic effects. In addition to the high-VOC biochars, a low-VOC biochar was tested which did not emit any VOCs and was even able to sorb VOCs from the VOC-rich biochar to a certain extent. Thermal treatment and blending with low-VOC biochar are methods which could be used in practise to treat high-VOC biochar, reducing VOC emissions. This study revealed significant new findings on the topic of VOCs in biochar which highlights the need to include VOCs in the list of priority contaminants in biochar.

  3. Characterization of Odorous Compounds (VOC and Carbonyl Compounds) in the Ambient Air of Yeosu and Gwangyang, Large Industrial Areas of South Korea

    PubMed Central

    Seo, Young-Kyo; Suvarapu, Lakshmi Narayana; Baek, Sung-Ok

    2014-01-01

    Odorous compounds play an important role in air pollution in industrial areas and the residential areas surrounding them. This study measured the odorous volatile organic compounds (VOC) and carbonyl compounds at Yeosu and Gwangyang, two large industrial areas of South Korea, during four seasons of 2008-2009. Along with these two cities, the same odorous compounds were measured at Suncheon, which was selected as a control site. The concentrations of VOC and carbonyl compounds that were listed as odorous air pollutants by the Ministry of Environment of South Korea are discussed. Benzene and formaldehyde were included in the target analytes because of their carcinogenic nature. Most researchers only examined the concentration of odorous compounds in ambient air but the present study evaluated the odor intensity, which is a new parameter that will help better understand the precise odor perceived by people. This paper describes the seasonal variations and spatial distribution of the above-mentioned odorous compounds at the specified sites. Pearson correlation coefficients between the odorous compounds and other air pollutants, such as ozone, CO, SO2, NO2, and PM10, and meteorological conditions, such as temperature and wind speed, provide the source information of odorous VOC and carbonyl compounds. PMID:25309959

  4. Solid-phase microcolumn extraction and gas chromatography-mass spectrometry identification of volatile organic compounds emitted by paper.

    PubMed

    Hrivnák, Ján; Tölgyessy, Peter; Figedyová, Sona; Katuscák, Svetozár

    2009-11-15

    A rapid non-destructive sampling technique for the analysis of volatile organic compounds (VOCs) emitted by paper sheets is described. A capillary, which is connected to a microcolumn packed with Tenax TA, is inserted between two sheets at the centre of a paper stack encapsulated inside a PET/Al/PE composite foil. The other end of the microcolumn is connected to a gas-tight syringe and an appropriate volume of gaseous phase is aspirated. The microcolumn is then thermally desorbed in a modified GC inlet (modification is presented) and analysed by gas chromatography-mass spectrometry (GC-MS). In the chromatogram from the analysis of artificially aged paper sample 21 compounds were identified. Advantages of the method including the short sampling time (1 min), simplicity and economic aspect are discussed.

  5. Characterizations of volatile organic compounds (VOCs) from vehicular emissions at roadside environment: The first comprehensive study in Northwestern China

    NASA Astrophysics Data System (ADS)

    Li, Bowei; Ho, Steven Sai Hang; Xue, Yonggang; Huang, Yu; Wang, Liqin; Cheng, Yan; Dai, Wenting; Zhong, Haobin; Cao, Junji; Lee, Shuncheng

    2017-07-01

    Vehicular emission (VE) is one of the important anthropogenic sources for ground-level volatile organic compounds (VOCs) in both urban and suburban areas. A first comprehensive campaign was conducted at an urban roadside in Xi'an, China in summer, 2016. A total of 57 VOCs, as known as critical surface ozone (O3) precursors, and other trace gases were measured simultaneously during the sampling period. Iso-pentane, a tracer of gasoline evaporation, was the most abundant VOC in the roadside samples, followed by isobutane and benzene, attributed to the largest composition (∼70%) of gasoline-fueled vehicles on the road. The molar ratio of toluene/benzene (T/B) in our study (0.36) is far lower than the range reported in other cities, indicating the stronger contributions from diesel emissions. The results of source apportionment achieved with positive matrix factorization (PMF) receptor model were highly consistent with the vehicles compositions, strongly evidenced that the precise characterization of the VE sources from those marker species. The degrees of individual compound contributed to O3 production were weighed by ozone formation potential (OFP). Propylene (20%), 1-butene (11%) and iso-pentane(10%) were the top three contributors at the roadside. The information of this study complements the VOCs database regarding to the VE sources in Northwestern China.

  6. Evaluation of an on-line methodology for measuring volatile organic compounds (VOC) fluxes by eddy-covariance with a PTR-TOF-Qi-MS

    NASA Astrophysics Data System (ADS)

    Loubet, Benjamin; Buysse, Pauline; Lafouge, Florence; Ciuraru, Raluca; Decuq, Céline; Zurfluh, Olivier

    2017-04-01

    Field scale flux measurements of volatile organic compounds (VOC) are essential for improving our knowledge of VOC emissions from ecosystems. Many VOCs are emitted from and deposited to ecosystems. Especially less known, are crops which represent more than 50% of French terrestrial surfaces. In this study, we evaluate a new on-line methodology for measuring VOC fluxes by Eddy Covariance with a PTR-Qi-TOF-MS. Measurements were performed at the ICOS FR-GRI site over a crop using a 30 m long high flow rate sampling line and an ultrasonic anemometer. A Labview program was specially designed for acquisition and on-line covariance calculation: Whole mass spectra ( 240000 channels) were acquired on-line at 10 Hz and stored in a temporary memory. Every 5 minutes, the spectra were mass-calibrated and normalized by the primary ion peak integral at 10 Hz. The mass spectra peaks were then retrieved from the 5-min averaged spectra by withdrawing the baseline, determining the resolution and using a multiple-peak detection algorithm. In order to optimize the peak detection algorithm for the covariance, we determined the covariances as the integrals of the peaks of the vertical-air-velocity-fluctuation weighed-averaged-spectra. In other terms, we calculate , were w is the vertical component of the air velocity, Sp is the spectra, t is time, lag is the decorrelation lag time and <.> denotes an average. The lag time was determined as the decorrelation time between w and the primary ion (at mass 21.022) which integrates the contribution of all reactions of VOC and water with the primary ion. Our algorithm was evaluated by comparing the exchange velocity of water vapor measured by an open path absorption spectroscopy instrument and the water cluster measured with the PTRQi-TOF-MS. The influence of the algorithm parameters and lag determination is discussed. This study was supported by the ADEME-CORTEA COV3ER project (http://www6.inra.fr/cov3er).

  7. The pollution characteristics of odor, volatile organochlorinated compounds and polycyclic aromatic hydrocarbons emitted from plastic waste recycling plants.

    PubMed

    Tsai, Chung-Jung; Chen, Mei-Lien; Chang, Keng-Fu; Chang, Fu-Kuei; Mao, I-Fang

    2009-02-01

    Plastic waste treatment trends toward recycling in many countries; however, the melting process in the facilities which adopt material recycling method for treating plastic waste may emit toxicants and cause sensory annoyance. The objectives of this study were to analyze the pollution characteristics of the emissions from the plastic waste recycling plants, particularly in harmful volatile organochlorinated compounds, polycyclic aromatic hydrocarbons (PAHs), odor levels and critical odorants. Ten large recycling plants were selected for analysis of odor concentration (OC), volatile organic compounds (VOCs) and PAHs inside and outside the plants using olfactometry, gas chromatography-mass spectrometry and high performance liquid chromatography-fluorescence detector, respectively. The olfactometric results showed that the melting processes used for treating polyethylene/polypropylene (PE/PP) and polyvinyl chloride (PVC) plastic waste significantly produced malodor, and the odor levels at downwind boundaries were 100-229 OC, which all exceeded Taiwan's EPA standard of 50 OC. Toluene, ethylbenzene, 4-methyl-2-pentanone, methyl methacrylate and acrolein accounted for most odors compared to numerous VOCs. Sixteen organochlorinated compounds were measured in the ambient air emitted from the PVC plastic waste recycling plant and total concentrations were 245-553 microg m(-3); most were vinyl chloride, chloroform and trichloroethylene. Concentrations of PAHs inside the PE/PP plant were 8.97-252.16 ng m(-3), in which the maximum level were 20-fold higher than the levels detected from boundaries. Most of these recycling plants simply used filter to treat the melting fumes, and this could not efficiently eliminate the gaseous compounds and malodor. Improved exhaust air pollution control were strongly recommended in these industries.

  8. Measurements of Volatile Organic Compounds (VOCs) from Biomass Combustion - Emission Ratios, OH Reactivities and SOA Precursors

    NASA Astrophysics Data System (ADS)

    Kuster, W. C.; Gilman, J. B.; Goldan, P. D.; Warneke, C.; Degouw, J.; Veres, P. R.; Burling, I. R.; Yokelson, R. J.

    2009-12-01

    Multiple instruments including a gas chromatograph/mass spectrometer (GC/MS), a proton transfer reaction mass spectrometer (PTR-MS), a proton ion trap mass spectrometer (PIT-MS), a negative-ion proton-transfer chemical-ionization mass spectrometer (NI-PT-CIMS) and a Fourier-transform infrared spectrometer (FTIR) acquired data from 77 burns of various biomass fuels conducted at the U.S. Department of Agriculture (USDA) Forest Sciences Laboratory (FSL) in Missoula, MT in February 2009. We compare VOC measurements of oxygenates, aromatics and biogenics from the various instruments as well as from the various fuel types collected in southeastern and southwestern regions of the United States. The relative contribution of the combustion species to the total reactivity with the OH radical is calculated and compared to ambient air reactivity in various locations. Total reactivity for measured species in these fires occasionally exceeded 1000 sec-1 with the majority of this reactivity due to alkenes. In addition, we investigate the relative contribution of the combustion species to the potential for secondary organic aerosol (SOA) formation. Measurements of several compounds not previously reported in various urban ambient air measurement campaigns such as pyrazole (C3H4N2), pyrrole (C4H5N), benzofuran (C8H6O) and 2-furanaldehyde (C5H4O2), which are highly reactive with OH, will be presented.

  9. Assessment of neurobehavioral response in humans to low-level volatile organic compound (VOC) sources

    SciTech Connect

    Otto, D.A.

    1991-06-01

    Occupants of sick buildings often complain of CNS symptoms including headache and memory loss, but little objective evidence of neurobehavioral effects exists. Available evidence of neurobehavioral effects of low level VOC exposure representative of new buildings is reviewed. Methods suitable for studying the neurobehavioral effects of low-level VOC exposure--including computerized behavioral tests, balance tests and sensory evoked potentials--are reviewed. The use of computerized behavioral tests in conjunction with symptom questionnaires is recommended for low-level VOC studies.

  10. Ground water: volatile organic compounds (VOC's). January 1970-December 1988 (Citations from the NTIS data base). Report for January 1970-December 1988

    SciTech Connect

    Not Available

    1988-12-01

    This bibliography contains citations concerning volatile organic compounds (VOC's) in ground water. Articles cover the detection, identification, and quantification of VOC's in ground water. Detection methods are covered as well as means for following the spread of the compounds. Citations also cover the removal of volatile organic compounds from groundwater. Superfund decisions, environmental impact statements, and reports of the Installation Restoration Program undertaken by the military are included. (Contains 161 citations fully indexed and including a title list.)

  11. Emission and profile characteristic of volatile organic compounds emitted from coke production, iron smelt, heating station and power plant in Liaoning Province, China.

    PubMed

    Shi, Jianwu; Deng, Hao; Bai, Zhipeng; Kong, Shaofei; Wang, Xiuyan; Hao, Jiming; Han, Xinyu; Ning, Ping

    2015-05-15

    107 kinds of C₂-C₁₂ volatile organic compound (VOC) mass concentrations and profiles for four types of coal-fired stationary sources in Liaoning Province were studied by a dilution sampling system and GC-MS analysis method, which are of significant importance with regard to VOC emissions in northeast of China. The results showed that there were some differences among these VOC source profiles. The total mass concentrations of analyzed 107 VOC species varied from 10,917 to 19,652 μg m(-3). Halogenated hydrocarbons exhibited higher mass percentages for the VOC source profiles of iron smelt (48.8%) and coke production plant (37.7%). Aromatic hydrocarbons were the most abundant in heating station plant (69.1%). Ketones, alcohols and acetates held 45.0% of total VOCs in thermal power plant. For non-methane hydrocarbons (NMHCs), which are demanded for photochemical assessment in the USA, toluene and n-hexane were the most abundant species in the iron smelt, coke production and thermal power plant, with the mass percentages of 64.8%, 52.7% and 38.6%, respectively. Trimethylbenzene, n-propylbenzene and o,m-ethyltoluene approximately accounted for 70.0% in heating station plant. NMHCs emitted from coke production, iron smelt, heating station and power plant listed above presented different chemical reactivities. The average OH loss rate of NMHCs from heating station, was 4 to 5.6 times higher than that of NMHCs from iron smelt, coke production and power plant, which implies that VOCs emitted from heating station in northeast of China should be controlled firstly to avoid photochemical ozone pollution and protect human health. There are significant variations in the ratios of benzene/toluene and m, p-xylene/ethylbenzene of these coal-fired source profiles. The representativeness of the coal-fired sources studied and the VOC samples collected should be more closely examined. The accuracy of VOC source profiles related to coal-fired processes is highly dependent on

  12. Trends in selected ambient volatile organic compound (VOC) concentrations and a comparison to mobile source emission trends in California's South Coast Air Basin

    NASA Astrophysics Data System (ADS)

    Pang, Yanbo; Fuentes, Mark; Rieger, Paul

    2015-12-01

    Trends in ambient concentrations of Volatile Organic Compounds (VOC) in the South Coast Air Basin (SoCAB) are compared to trends in VOC emissions from Light-Duty Gasoline Vehicles (LDGV) tested on chassis dynamometers and to trends observed in tunnel studies during the same period to understand the impacts of gasoline vehicle emissions on ambient VOC concentrations from 1999 to 2009. Annual median concentrations for most ambient VOCs decreased 40% from 1999 to 2009 in the SoCAB, based on data from the Photochemical Assessment Monitoring Stations (PAMS). Annual concentration decreases of most compounds, except 2,2,4-trimethylpentane, are highly correlated with the decrease of acetylene, a marker for tailpipe emissions from LDGV. This indicates that ambient VOC concentration decreases were likely due to tailpipe emission reductions from gasoline vehicles. Air Toxics Monitoring Network data also support this conclusion. Benzene concentration-normalized ratios for most compounds except ethane, propane, isoprene, and 2,2,4-trimethylpentane were stable even as these compound concentrations decreased significantly from 1999 to 2009. Such stability suggests that the main sources of ambient VOC were still the same from 1999 to 2009. The comparison of trends in dynamometer testing and tunnel studies also shows that tailpipe emissions remained the dominant source of tunnel LDGV emissions. The pronounced changes in 2,2,4-trimethylpentane ratios due to the introduction of Phase 3 gasoline also confirm the substantial impact of LDGV emissions on ambient VOCs. Diurnal ambient VOC data also suggest that LDGV tailpipe emissions remained the dominant source of ambient VOCs in the SoCAB in 2009. Our conclusion, which is that current inventory models underestimate VOC emissions from mobile sources, is consistent with that of several recent studies of ambient trends in the SoCAB. Our study showed that tailpipe emissions remained a bigger contributor to ambient VOCs than evaporative

  13. Degradation Pathways for Geogenic Volatile Organic Compounds (VOCs) in Soil Gases from the Solfatara Crater (Campi Flegrei, Southern Italy).

    NASA Astrophysics Data System (ADS)

    Tassi, F.; Venturi, S.; Cabassi, J.; Capecchiacci, F.; Nisi, B., Sr.; Vaselli, O.

    2014-12-01

    The chemical composition of volatile organic compounds (VOCs) in soil gases from the Solfatara crater (Campi Flegrei, Southern Italy) was analyzed to investigate the effects of biogeochemical processes occurring within the crater soil on gases discharged from the hydrothermal reservoir and released into the atmosphere through diffuse degassing. In this system, two fumarolic vents (namely Bocca Grande and Bocca Nuova) are the preferential pathways for hydrothermal fluid uprising. For our goal, the chemistry of VOCs discharged from these sites were compared to that of soil gases. Our results highlighted that C4-C9 alkanes, alkenes, S-bearing compounds and alkylated aromatics produced at depth were the most prone to degradation processes, such as oxidation-reduction and hydration-dehydration reactions, as well as to microbial activity. Secondary products, which were enriched in sites characterized by low soil gas fluxes, mostly consisted of aldheydes, ketons, esters, ethers, organic acids and, subordinately, alcohols. Benzene, phenol and hydrofluorocarbons (HCFCs) produced at depth were able to transit through the soil almost undisturbed, independently on the emission rate of diffuse degassing. The presence of cyclics was possibly related to an independent low-temperature VOC source, likely within sedimentary formations overlying the hydrothermal reservoir. Chlorofluorocarbons (CFCs) were possibly due to air contamination. This study demonstrated the strict control of biogeochemical processes on the behaviour of hydrothermal VOCs that, at least at a local scale, may have a significant impact on air quality. Laboratory experiments conducted at specific chemical-physical conditions and in presence of different microbial populations may provide useful information for the reconstruction of the degradation pathways controlling fate and behaviour of VOCs in the soil.

  14. Characterization of VOCs and odorants on PM from animal feeding operations

    USDA-ARS?s Scientific Manuscript database

    Volatile organic compounds (VOC) emitted from animal feeding operations negatively impact local and potentially regional air quality though the release of both odorous and ozone precursor molecules. Characterizing emissions of VOCs from AFOs is strongly influenced by both the method and location of ...

  15. Use of Compound-Specific Stable Isotope Analysis to Distinguish Between Vapor Intrusion and Indoor Sources of VOCs

    DTIC Science & Technology

    2013-11-01

    xylenes cis-1,2-DCE cis-1,2-dichloroethylene COC Chemical of concern CSIA Compound-specific stable isotope analysis cVOC Chlorinated volatile organic...found to be distinct from most potential indoor sources. • Issues with hydrocarbon sites. At chlorinated hydrocarbon sites, two isotope ratios can...follows: • Task 1: Validate the use of active adsorbent samplers for the collection of vapor-phase samples for carbon, chlorine , and hydrogen CSIA of

  16. Industrial sector-based volatile organic compound (VOC) source profiles measured in manufacturing facilities in the Pearl River Delta, China.

    PubMed

    Zheng, Junyu; Yu, Yufan; Mo, Ziwei; Zhang, Zhou; Wang, Xinming; Yin, Shasha; Peng, Kang; Yang, Yang; Feng, Xiaoqiong; Cai, Huihua

    2013-07-01

    Industrial sector-based VOC source profiles are reported for the Pearl River Delta (PRD) region, China, based source samples (stack emissions and fugitive emissions) analyzed from sources operating under normal conditions. The industrial sectors considered are printing (letterpress, offset and gravure printing processes), wood furniture coating, shoemaking, paint manufacturing and metal surface coating. More than 250 VOC species were detected following US EPA methods TO-14 and TO-15. The results indicated that benzene and toluene were the major species associated with letterpress printing, while ethyl acetate and isopropyl alcohol were the most abundant compounds of other two printing processes. Acetone and 2-butanone were the major species observed in the shoemaking sector. The source profile patterns were found to be similar for the paint manufacturing, wood furniture coating, and metal surface coating sectors, with aromatics being the most abundant group and oxygenated VOCs (OVOCs) as the second largest contributor in the profiles. While OVOCs were one of the most significant VOC groups detected in these five industrial sectors in the PRD region, they have not been reported in most other source profile studies. Such comparisons with other studies show that there are differences in source profiles for different regions or countries, indicating the importance of developing local source profiles. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

  17. The European wool-carder bee (Anthidium manicatum) eavesdrops on plant volatile organic compounds (VOCs) during trichome collection.

    PubMed

    Graham, Kelsey K; Brown, Steve; Clarke, Stephanie; Röse, Ursula S R; Starks, Philip T

    2017-08-19

    The plant-pollinator relationship is generally considered mutualistic. This relationship is less clear, however, when pollinators also cause tissue damage. Some Megachilidae bees collect plant material for nests from the plants they pollinate. In this study, we examined the relationship between Anthidium manicatum, the European wool-carder bee, and the source of its preferred nesting material - Stachys byzantina, lamb's ear. Female A. manicatum use their mandibles to trim trichomes from plants for nesting material (a behaviour dubbed "carding"). Using volatile organic compound (VOC) headspace analysis and behavioural observations, we explored (a) how carding effects S. byzantina and (b) how A. manicatum may choose specific S. byzantina plants. We found that removal of trichomes leads to a dissimilar VOC bouquet compared to intact leaves, with a significant increase in VOC detection following damage. A. manicatum also visit S. byzantina plants with trichomes removed at a greater frequency compared to plants with trichomes intact. Our data suggest that A. manicatum eavesdrop on VOCs produced by damaged plants, leading to more carding damage for individual plants due to increased detectability by A. manicatum. Accordingly, visitation by A. manicatum to S. byzantina may incur both a benefit (pollination) and cost (tissue damage) to the plant. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. In vivo analysis of palm wine (Elaeis guineensis) volatile organic compounds (VOCs) by proton transfer reaction-mass spectrometry

    NASA Astrophysics Data System (ADS)

    Lasekan, Ola; Otto, Sabine

    2009-04-01

    The in vivo volatile organic compounds (VOCs) release patterns in palm wine was carried out using the PTR-MS. In order to analyze the complex mixtures of VOCs in palm wine, the fragmentation patterns of 14 known aroma compounds of palm wine were also investigated. Results revealed masses m/z (43, 47, 61, 65, 75, 89 and 93) as the predominant ones measured in-breathe exhaled from the nose, during consumption of palm wine. Further studies of aroma's fragmentation patterns, showed that the m/z 43 is characteristic of fragment of various compounds, while m/z 47 is ethanol, m/z 61(acetic acid), m/z 65 (protonated ethanol cluster ions), m/z 75 (methyl acetate), m/z 89 (acetoin) and m/z 93 (2-phenylethanol) respectively. The dynamic release parameters (Imax and tmax) of the 7 masses revealed significant (P = 0.05) differences, between maximum intensity (Imax) and no significant (P = 0.05) differences between tmax among VOCs respectively.

  19. Emissions of volatile organic compounds (VOCs) from the food and drink industries of the European community

    NASA Astrophysics Data System (ADS)

    Passant, Neil R.; Richardson, Stephen J.; Swannell, Richard P. J.; Gibson, N.; Woodfield, M. J.; van der Lugt, Jan Pieter; Wolsink, Johan H.; Hesselink, Paul G. M.

    Estimates were made of the amounts of volatile organic compounds (VOCs) released into the atmosphere as a result of the industrial manufacture and processing of food and drink in the European Community. The estimates were based on a review of literature sources, industrial and government contacts and recent measurements. Data were found on seven food manufacturing sectors (baking, vegetable oil extraction, solid fat processing, animal rendering, fish meal processing, coffee production and sugar beet processing) and three drink manufacturing sectors (brewing, spirit production and wine making). The principle of a data quality label is advocated to illustrate the authors' confidence in the data, and to highlight areas for further research. Emissions of ethanol from bread baking and spirit maturation were found to be the principle sources. However, significant losses of hexane and large quantities of an ill-defined mixture of partially oxidized hydrocarbons were noted principally from seed oil extraction and the drying of plant material, respectively. This latter mixture included low molecular weight aldehydes, carboxylic acids, ketones, amines and esters. However, the precise composition of many emissions were found to be poorly understood. The total emission from the food and drink industry in the EC was calculated as 260 kt yr -1. However, many processes within the target industry were found to be completely uncharacterized and therefore not included in the overall estimate (e.g. soft drink manufacture, production of animal food, flavourings, vinegar, tea, crisps and other fried snacks). Moreover, the use of data quality labels illustrated the fact that many of our estimates were based on limited data. Hence, further emissions monitoring is recommended from identified sources (e.g. processing of sugar beet, solid fat and fish meal) and from uncharacterized sources.

  20. Optimizing the emission inventory of volatile organic compounds (VOCs) based on network observations

    NASA Astrophysics Data System (ADS)

    Chen, Sheng-Po; Liu, Wen-Tzu; Ou-Yang, Chang-Feng; Chang, Julius S.; Wang, Jia-Lin

    2014-02-01

    Hourly observations of 56 non-methane hydrocarbons (NMHCs) performed by a network of photochemical assessment monitoring stations (PAMS) at 11 locations across Taiwan were used to evaluate 56 speciated emissions and the resulting simulations of an air quality model. Based on the PAMS observations at two urban sites, emission modification was made for the 56 PAMS species in the model. To further test the applicability of this emission correction approach, the same modified emissions were subject to seven different meteorological conditions and comparison with observations of all the 11 PAMS sites. Originally there was a minimum of only 8 of 56 species showed agreement with observations for the worst of the 11 PAMS sites and 28 of 56 species for the best site. With modified emissions, the number increased to 13-52 species across the 11 PAMS sites, demonstrating that the simple urban based correction procedure has broad applicability. When applying this modification of PAMS emissions to the simulations of other air quality gases, SO2 and NOx showed small changes compared with observations (-0.27% and -2.51%, respectively), while total VOC concentrations showed significant changes (+15.28%) as a result of the adjustment in VOC emissions (+26.7%). Although VOCs are the precursor of ozone, the relatively large changes in VOC did not seem to affect ozone formation to the similar extent, only resulting in the changes of average O3 by 2.9 ppb (+9.41%). It shows that although the emission modification improves individual VOC simulations, the performance in oxidant simulation is still largely unaltered. Although the original U.S. VOC emission profiles can capture the general features of ambient VOCs, further optimization of emissions may still be needed by referencing extensive observations, so that emissions can better fit domestic conditions and accuracy in model simulations can be improved.

  1. Rapid detection of pathogenic bacteria by volatile organic compound (VOC) analysis

    NASA Astrophysics Data System (ADS)

    Senecal, Andre G.; Magnone, Joshua; Yeomans, Walter; Powers, Edmund M.

    2002-02-01

    Developments in rapid detection technologies have made countless improvements over the years. However, because of the limited sample that these technologies can process in a single run, the chance of capturing and identifying a small amount of pathogens is difficult. The problem is further magnified by the natural random distribution of pathogens in foods. Methods to simplify pathogenic detection through the identification of bacteria specific VOC were studied. E. coli O157:H7 and Salmonella typhimurium were grown on selected agar medium to model protein, and carbohydrate based foods. Pathogenic and common spoilage bacteria (Pseudomonas and Morexella) were screened for unique VOC production. Bacteria were grown on agar slants in closed vials. Headspace sampling was performed at intervals up to 24 hours using Solid Phase Micro-Extraction (SPME) techniques followed by GC/MS analysis. Development of unique volatiles was followed to establish sensitivity of detection. E. coli produced VOC not found in either Trypticase Soy Yeast (TSY) agar blanks or spoilage organism samples were - indole, 1-decanol, and 2-nonanone. Salmonella specific VOC grown on TSY were 3-methyl-1-butanol, dimethyl sulfide, 2-undecanol, 2-pentadecanol and 1-octanol. Trials on potato dextrose agar (PDA) slants indicated VOC specific for E. coli and Salmonella when compared to PDA blanks and Pseudomonas samples. However, these VOC peaks were similar for both pathogens. Morexella did not grow on PDA slants. Work will continue with model growth mediums at various temperatures, and mixed flora inoculums. As well as, VOC production based on the dynamics of bacterial growth.

  2. Assessment of regional influence from a petrochemical complex by modeling and fingerprint analysis of volatile organic compounds (VOCs)

    NASA Astrophysics Data System (ADS)

    Su, Yuan-Chang; Chen, Sheng-Po; Tong, Yu-Huei; Fan, Chen-Lun; Chen, Wei-Hao; Wang, Jia-Lin; Chang, Julius S.

    2016-09-01

    This study aimed to demonstrate a strategy to investigate the influence of volatile organic compounds (VOCs) on its neighboring districts from a gigantic petrochemical complex. Monitoring of the VOCs in the region was achieved by a nine-station network, dubbed photochemical assessment measurement stations (PAMS), which produced speciated mixing ratios of 54 non-methane hydrocarbons (NMHCs) to represent VOCs with an hourly resolution within a 20 km radius. One-year (2013/10/1-2014/9/30) worth of PAMS data from the network were used in forms of total NMHCs (called PAMS-TNMHC) and speciated mixing ratios. Three dimensional modeling coupled with PAMS measurements successfully elucidated how the study domain was affected by the petrochemical complex and distant sources under three typical seasonal wind patterns: northeast monsoonal, southwest monsoonal, and local-circulation. More exquisite analysis of influence on the neighboring districts was permitted with the use of speciated mixing ratios of VOCs provided by the PAMS network. The ratios of ethylene/acetylene (E/A) > 3 and propylene/acetylene (P/A) > 1.5 were used as indicators to reveal the PAMS sites affected by the petrochemical emissions. Consequently, the hourly speciated data from the nine PAMS sites enabled a finer assessment of the districts affected by the complex to calculate the percent time of influence (dubbed TI%) for all the sites (districts). It was found that the region was more affected by the complex under both the northeast monsoonal and the local-circulation wind types with some of the PAMS sites greater than 5% for the TI%. By contrast, influence on the region was found minimal under the southwest monsoonal flow with the TI% small than 1.5% across all sites. This study successfully devised a method of assessment with the use of speciated measurements of selected VOCs and modeling to assess the influence of a prominent source on the neighboring districts by filtering out irrelevant sources under

  3. Source Signature of Volatile Organic Compounds (VOCs) associated with oil and natural gas operations in Utah and Colorado

    NASA Astrophysics Data System (ADS)

    Gilman, J.; Lerner, B. M.; Warneke, C.; Holloway, J. S.; Peischl, J.; Ryerson, T. B.; Young, C. J.; Edwards, P.; Brown, S. S.; Wolfe, D. E.; Williams, E. J.; De Gouw, J. A.

    2012-12-01

    The U.S. Energy Information Administration has reported a sharp increase in domestic oil and natural gas production from "unconventional" reserves (e.g., shale and tight sands) between 2005 and 2012. The recent growth in drilling and fossil fuel production has led to environmental concerns regarding local air quality. Severe wintertime ozone events (greater than 100 ppb ozone) have been observed in Utah's Uintah Basin and Wyoming's Upper Green River Basin, both of which contain large natural gas fields. Raw natural gas is a mixture of approximately 60-95 mole percent methane while the remaining fraction is composed of volatile organic compounds (VOCs) and other non-hydrocarbon gases. We measured an extensive set of VOCs and other trace gases near two highly active areas of oil and natural gas production in Utah's Uintah Basin and Colorado's Denver-Julesburg Basin in order to characterize primary emissions of VOCs associated with these industrial operations and identify the key VOCs that are precursors for potential ozone formation. UBWOS (Uintah Basin Winter Ozone Study) was conducted in Uintah County located in northeastern Utah in January-February 2012. Two Colorado studies were conducted at NOAA's Boulder Atmospheric Observatory in Weld County in northeastern Colorado in February-March 2011 and July-August 2012 as part of the NACHTT (Nitrogen, Aerosol Composition, and Halogens on a Tall Tower) and SONNE (Summer Ozone Near Natural gas Emissions) field experiments, respectively. The C2-C6 hydrocarbons were greatly enhanced for all of these studies. For example, the average propane mixing ratio observed during the Utah study was 58 ppb (median = 35 ppb, minimum = 0.8, maximum = 520 ppb propane) compared to urban averages which range between 0.3 and 6.0 ppb propane. We compare the ambient air composition from these studies to urban measurements in order to show that the VOC source signature from oil and natural gas operations is distinct and can be clearly

  4. Physiological variability in volatile organic compounds (VOCs) in exhaled breath and released from faeces due to nutrition and somatic growth in a standardized caprine animal model.

    PubMed

    Fischer, Sina; Trefz, Phillip; Bergmann, Andreas; Steffens, Markus; Ziller, Mario; Miekisch, Wolfram; Schubert, Jochen S; Köhler, Heike; Reinhold, Petra

    2015-05-14

    Physiological effects may change volatile organic compound (VOC) concentrations and may therefore act as confounding factors in the definition of VOCs as disease biomarkers. To evaluate the extent of physiological background variability, this study assessed the effects of feed composition and somatic growth on VOC patterns in a standardized large animal model. Fifteen clinically healthy goats were followed during their first year of life. VOCs present in the headspace over faeces, exhaled breath and ambient air inside the stable were repeatedly assessed in parallel with the concentrations of glucose, protein, and albumin in venous blood. VOCs were collected and analysed using solid-phase or needle-trap microextraction and gas chromatograpy together with mass spectroscopy. The concentrations of VOCs in exhaled breath and above faeces varied significantly with increasing age of the animals. The largest variations in volatiles detected in the headspace over faeces occurred with the change from milk feeding to plant-based diet. VOCs above faeces and in exhaled breath correlated significantly with blood components. Among VOCs exhaled, the strongest correlations were found between exhaled nonanal concentrations and blood concentrations of glucose and albumin. Results stress the importance of a profound knowledge of the physiological backgrounds of VOC composition before defining reliable and accurate marker sets for diagnostic purposes.

  5. Detection and quantification of methane and VOC emissions from oil and gas production operations using remote measurements, Interim report

    EPA Science Inventory

    Improved understanding of air pollutant emissions from oil and gas production operations is needed. With a steadily increasing number of production sources, the impact of emitted volatile organic compounds (VOCs) on regional ozone is potentially significant. As the separation dis...

  6. Detection and quantification of methane and VOC emissions from oil and gas production operations using remote measurements, Interim report

    EPA Science Inventory

    Improved understanding of air pollutant emissions from oil and gas production operations is needed. With a steadily increasing number of production sources, the impact of emitted volatile organic compounds (VOCs) on regional ozone is potentially significant. As the separation dis...

  7. Analysis of a GC/MS thermal desorption system with simultaneous sniffing for determination of off-odor compounds and VOCs in fumes formed during extrusion coating of low-density polyethylene.

    PubMed

    Villberg, K; Veijanen, A

    2001-03-01

    A thermal desorption equipment introducing volatile organic compounds (VOCs) into the gas chromatographic/ mass spectrometric system (GC/MS) with simultaneous sniffing (SNIFF) is a suitable method for identifying the volatile organic off-odor compounds formed during the extrusion coating process of low-density polyethylene. Fumes emitted during the extrusion coating process of three different plastic materials were collected at two different temperatures (285 and 315 degrees C) from an outgoing pipe and near an extruder. The VOCs of fumes were analyzed by drawing a known volume of air through the adsorbent tube filled with a solid adsorbent (Tenax GR). The air samples were analyzed by using a special thermal desorption device and GC/MS determination. The simultaneous sniffing was carried out to detect off-odors and to assist in the identification of those compounds that contribute to tainting and smelling. The amounts of off-odor carbonyl compounds and the total content of the volatile organic compounds were determined. The most odorous compounds were identified as carboxylic acids while the majority of the volatile compounds were hydrocarbons. The detection and quantification of carboxylic acids were based on the characteristic ions of their mass spectra. The higher the extrusion temperature the more odors were detected. An important observation was that the total concentration of volatiles was dependent not only on the extrusion temperature but also on the plastic material.

  8. An Analysis of Air Pollution Control Technologies for Shipyard Emitted Volatile Organic Compounds (VOCS)

    DTIC Science & Technology

    1993-03-01

    reducing the overall amount of coating used in the Shipbuilding Industry are High Volume Low Pressure ( HVLP ) systems and airless spray equipment. Other...systems, such as plural component systems that mix two-part paints at the spray gun , reduce the volume of coating used by reducing the amount of pre-mixed...carbon dioxide expands into a gas as it is released horn pressure when the solution is sprayed . As the coating sprays from the gun , atomization

  9. Occupational hygiene in terms of volatile organic compounds (VOCs) and bioaerosols at two solid waste management plants in Finland

    SciTech Connect

    Lehtinen, Jenni; Tolvanen, Outi; Nivukoski, Ulla; Veijanen, Anja; Hänninen, Kari

    2013-04-15

    Highlights: ► Odorous VOCs: acetic acid, 2,3-butanedione, ethyl acetate, alpha-pinene and limonene. ► VOC concentrations did not exceed occupational exposure limit concentrations. ► 2,3-Butanedione as the health effecting compound is discussed. ► Endotoxin concentrations may cause health problems in waste treatment. - Abstract: Factors affecting occupational hygiene were measured at the solid waste transferring plant at Hyvinkää and at the optic separation plant in Hämeenlinna. Measurements consisted of volatile organic compounds (VOCs) and bioaerosols including microbes, dust and endotoxins. The most abundant compounds in both of the plants were aliphatic and aromatic hydrocarbons, esters of carboxylic acids, ketones and terpenes. In terms of odour generation, the most important emissions were acetic acid, 2,3-butanedione, ethyl acetate, alpha-pinene and limonene due to their low threshold odour concentrations. At the optic waste separation plant, limonene occurred at the highest concentration of all single compounds of identified VOCs. The concentration of any single volatile organic compound did not exceed the occupational exposure limit (OEL) concentration. However, 2,3-butanedione as a health risk compound is discussed based on recent scientific findings linking it to lung disease. Microbe and dust concentrations were low at the waste transferring plant. Only endotoxin concentrations may cause health problems; the average concentration inside the plant was 425 EU/m{sup 3} which clearly exceeded the threshold value of 90 EU/m{sup 3}. In the wheel loader cabin the endotoxin concentrations were below 1 EU/m{sup 3}. High microbial and endotoxin concentrations were measured in the processing hall at the optic waste separation plant. The average concentration of endotoxins was found to be 10,980 EU/m{sup 3}, a concentration which may cause health risks. Concentrations of viable fungi were quite high in few measurements in the control room. The most

  10. Investigation of key parameters influencing the efficient photocatalytic oxidation of indoor volatile organic compounds (VOCs)

    SciTech Connect

    Quici, Natalia; Kibanova, Daria; Vera, Maria Laura; Choi, Hyeok; Dionysiou, Dionysios D.; Litter, Marta I.; Cervini-Silva, Javiera; Hodgson, Alfred T.; Destaillats, Hugo; Destaillats, Hugo

    2008-06-01

    Photocatalytic oxidation of indoor VOCs has the potential to eliminate pollutants from indoor environments, thus effectively improving and/or maintaining indoor air quality while reducing ventilation energy costs. Design and operation of UV photocatalytic oxidation (UVPCO) air cleaners requires optimization of various parameters to achieve highest pollutant removal efficiencies while avoiding the formation of harmful secondary byproducts and maximizing catalyst lifetime.

  11. Characterisation of volatile organic compounds (VOCs) released by the composting of different waste matrices.

    PubMed

    Schiavon, Marco; Martini, Luca Matteo; Corrà, Cesare; Scapinello, Marco; Coller, Graziano; Tosi, Paolo; Ragazzi, Marco

    2017-09-01

    The complaints arising from the problem of odorants released by composting plants may impede the construction of new composting facilities, preclude the proper activity of existing facilities or even lead to their closure, with negative implications for waste management and local economy. Improving the knowledge on VOC emissions from composting processes is of particular importance since different VOCs imply different odour impacts. To this purpose, three different organic matrices were studied in this work: dewatered sewage sludge (M1), digested organic fraction of municipal solid waste (M2) and untreated food waste (M3). The three matrices were aerobically biodegraded in a bench-scale bioreactor simulating composting conditions. A homemade device sampled the process air from each treatment at defined time intervals. The samples were analysed for VOC detection. The information on the concentrations of the detected VOCs was combined with the VOC-specific odour thresholds to estimate the relative weight of each biodegraded matrix in terms of odour impact. When the odour formation was at its maximum, the waste gas from the composting of M3 showed a total odour concentration about 60 and 15,000 times higher than those resulting from the composting of M1 and M2, respectively. Ethyl isovalerate showed the highest contribution to the total odour concentration (>99%). Terpenes (α-pinene, β-pinene, p-cymene and limonene) were abundantly present in M2 and M3, while sulphides (dimethyl sulphide and dimethyl disulphide) were the dominant components of M1. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Screening the Emission Sources of Volatile Organic Compounds (VOCs) in China Based on Multi-effect Evaluation

    NASA Astrophysics Data System (ADS)

    Niu, H., Jr.

    2015-12-01

    Volatile organic compounds (VOCs) in the atmosphere have adverse impacts via three main pathways: photochemical ozone formation, secondary organic aerosol production, and direct toxicity to humans. Few studies have integrated these effects to prioritize control measures for VOCs sources. In this study, we developed a multi-effect evaluation methodology based on updated emission inventories and source profiles, which was combined with ozone formation potential (OFP), secondary organic aerosol potential (SOAP), and VOC toxicity data to identify important emission sources and key species. We derived species-specific emission inventories for 152 sources. The OFPs, SOAPs, and toxicity of each source were determined, and the contribution and share of each source to each of these adverse effects was calculated. Weightings were given to the three adverse effects by expert scoring, and the integrated impact was determined. Using 2012 as the base year, solvent usage and industrial process were found to be the most important anthropogenic sources, accounting for 24.2 and 23.1% of the integrated environmental effect, respectively. This was followed by biomass burning, transportation, and fossil fuel combustion, all of which had a similar contribution ranging from 16.7 to 18.6%. The top five industrial sources, including plastic products, rubber products, chemical fiber products, the chemical industry, and oil refining, accounted for nearly 70.0% of industrial emissions. In China, emissions reductions are required for styrene, toluene, ethylene, benzene, and m/p-xylene. The 10 most abundant chemical species contributed 76.5% of the integrated impact. Beijing, Chongqing, Shanghai, Jiangsu, and Guangdong were the five leading provinces when considering the integrated effects. Besides, the chemical mass balance model (CMB) was used to verify the VOCs inventories of 47 cities in China, so as to optimize our evaluation results. We suggest that multi-effect evaluation is necessary to

  13. Exposures to volatile organic compounds (VOCs) and associated health risks of socio-economically disadvantaged population in a "hot spot" in Camden, New Jersey

    NASA Astrophysics Data System (ADS)

    Wu, Xiangmei (May); Fan, Zhihua (Tina); Zhu, Xianlei; Jung, Kyung Hwa; Ohman-Strickland, Pamela; Weisel, Clifford P.; Lioy, Paul J.

    2012-09-01

    To address disparities in health risks associated with ambient air pollution for racial/ethnic minority groups, this study characterized personal and ambient concentrations of volatile organic compounds (VOCs) in a suspected hot spot of air pollution - the Village of Waterfront South (WFS), and an urban reference community - the Copewood/Davis Streets (CDS) neighborhood in Camden, New Jersey. Both are minority-dominant, impoverished communities. We collected 24-h integrated personal air samples from 54 WFS residents and 53 CDS residents, with one sample on a weekday and one on a weekend day during the summer and winter seasons of 2004-2006. Ambient air samples from the center of each community were also collected simultaneously during personal air sampling. Toluene, ethylbenzene, and xylenes (TEX) presented higher (p < 0.05) ambient levels in WFS than in CDS, particularly during weekdays. A stronger association between personal and ambient concentrations of MTBE and TEX was found in WFS than in CDS. Fourteen to forty-two percent of the variation in personal MTBE, hexane, benzene, and TEX was explained by local outdoor air pollution. These observations indicated that local sources impacted the community air pollution and personal exposure in WFS. The estimated cancer risks resulting from two locally emitted VOCs, benzene and ethylbenzene, and non-cancer neurological and respiratory effects resulting from hexane, benzene, toluene, and xylenes exceeded the US EPA risk benchmarks in both communities. These findings emphasized the need to address disparity in health risks associated with ambient air pollution for the socio-economically disadvantaged groups. This study also demonstrated that air pollution hot spots similar to WFS can provide robust setting to investigate health effects of ambient air pollution.

  14. Analysis of Volatile Organic Compounds Emitted by Plant Growth-Promoting Fungus Phoma sp. GS8-3 for Growth Promotion Effects on Tobacco

    PubMed Central

    Naznin, Hushna Ara; Kimura, Minako; Miyazawa, Mitsuo; Hyakumachi, Mitsuro

    2013-01-01

    We extracted volatile organic compounds (VOCs) emitted by a plant growth-promoting fungus (PGPF) Phoma sp. GS8-3 by gas chromatography and identified them by mass spectrometry. All of the identified compounds belonged to C4-C8 hydrocarbons. Volatiles varied in number and quantity by the culture period of the fungus (in days). 2-Methyl-propanol and 3-methyl-butanol formed the main components of the volatile blends for all the culture periods of fungus. Growth-promoting effects of the identified synthetic compounds were analyzed individually and in blends using tobacco plants. We found that the mixture of volatiles extracted from 3-day-old culture showed significant growth promotion in tobacco in vitro. The volatile blend showed better growth promotion at lower than higher concentrations. Our results confirm the potential role of volatile organic compounds in the mechanism of growth enhancement by GS8-3. PMID:23080408

  15. VOC identification and inter-comparison from laboratory biomass burning using PTR-MS and PIT-MS

    Treesearch

    C. Warneke; J. M. Roberts; P. Veres; J. Gilman; W. C. Kuster; I. Burling; R. Yokelson; J. A. de Gouw

    2011-01-01

    Volatile organic compounds (VOCs) emitted from fires of biomass commonly found in the southeast and southwest U.S. were investigated with PTR-MS and PIT-MS, which are capable of fast measurements of a large number of VOCs. Both instruments were calibrated with gas standards and mass dependent calibration curves are determined. The sensitivity of the PIT-MS linearly...

  16. Navy Compliance with Volatile Organic Compounds (VOC) Regulations for Marine Coatings

    DTIC Science & Technology

    1990-12-01

    antifouling polyisobutylene, Formula 133 MIL-P-22299 Paint, antifouling polyisobutylene, Formula 134 TT-L-1155 Linseed oil , alkyd refined 8 Reformulation...9 Epoxy Polyamide (MIL-P-2444 1) .............................. 9 Lead and Chromate-Free Oil Alkyd Primer (TT-P-645...Free Oil Alkyd Primer (TT-P-645). The formulation goal is to eliminate the zinc chromate and to lower the VOC to 340 g/l. Silicone-Alkyd Topcoat (TT-E

  17. Influence of relative humidity on VOC concentrations in indoor air.

    PubMed

    Markowicz, Pawel; Larsson, Lennart

    2015-04-01

    Volatile organic compounds (VOCs) may be emitted from surfaces indoors leading to compromised air quality. This study scrutinized the influence of relative humidity (RH) on VOC concentrations in a building that had been subjected to water damage. While air samplings in a damp room at low RH (21-22%) only revealed minor amounts of 2-ethylhexanol (3 μg/m(3)) and 2,2,4-trimethyl-1,3-pentanediol diisobutyrate (TXIB, 8 μg/m(3)), measurements performed after a rapid increase of RH (to 58-75%) revealed an increase in VOC concentrations which was 3-fold for 2-ethylhexanol and 2-fold for TXIB. Similar VOC emission patterns were found in laboratory analyses of moisture-affected and laboratory-contaminated building materials. This study demonstrates the importance of monitoring RH when sampling indoor air for VOCs in order to avoid misleading conclusions from the analytical results.

  18. Volatile Organic Compounds (VOCs) measurements onboard the HALO research aircraft during OMO-ASIA

    NASA Astrophysics Data System (ADS)

    Safadi, Layal; Neumaier, Marco; Fischbeck, Garlich; Geiger, Felix; Förster, Eric; Tomsche, Laura; Zahn, Andreas

    2017-04-01

    The objective of the OMO-Asia campaign that took place in summer 2015 was to study the free-radical chemistry at higher altitudes during the Asian summer monsoon taken over a wide area of Asia. VOC measurements (e.g. acetone, acetonitrile, benzene, and toluene) were conducted using a strongly modified instrument based on a commercial Proton-Transfer-Reaction Mass Spectrometer (PTRMS) from Ionicon. The PTRMS data are generally in good agreement with VOC measurements taken by the GC instrument from Max Planck Institute for Chemistry. In the outflow of the Monsoon plume acetone and acetonitrile volume mixing ratios (VMR) up to 1500 pptV and 180 pptV have been measured, respectively, pointing to a small contribution from biomass burning sources of which acetonitrile is an important tracer. Comparison with VOCs simulated in the atmospheric chemistry model EMAC model exhibits an underestimation (factor of 3 for acetone). The measured data were analyzed with the help of 10 days back trajectories to distinguish air mass origins. For air masses originating from North America (NA) an enhancement of 500 pptV acetone relative to the atmospheric background ( 500 pptV) can be traced back to active biogenic acetone sources in the NA boreal summer. An average enhancement of 400 pptV acetone comes from the Asian summer monsoon. Acetone - CO correlations in the monsoon relative to background air is being analyzed for further characterization and estimation of the sources.

  19. Characterizing the chemical evolution of air masses via multi-platform measurements of volatile organic compounds (VOCs) during CalNEX: Composition, OH reactivity, and potential SOA formation

    NASA Astrophysics Data System (ADS)

    Gilman, J. B.; Kuster, W. C.; Bon, D.; Warneke, C.; Lerner, B. M.; Williams, E. J.; Holloway, J. S.; Pollack, I. B.; Ryerson, T. B.; Atlas, E. L.; Blake, D. R.; Herndon, S. C.; Zahniser, M. S.; Vlasenko, A. L.; Li, S.; Alvarez, S. L.; Rappenglueck, B.; Flynn, J. H.; Grossberg, N.; Lefer, B. L.; De Gouw, J. A.

    2011-12-01

    Volatile organic compounds (VOCs) are critical components in the photochemical production of ozone (O3) and secondary organic aerosol (SOA). During the CalNex 2010 field campaign, an extensive set of VOCs were measured at the Pasadena ground site, and aboard the NOAA WP-3D aircraft and the WHOI Research Vessel Atlantis. The measurements from each platform provide a unique perspective into the emissions, transport, and atmospheric processing of VOCs within the South Coast Air Basin (SoCAB). The observed enhancement ratios of the hydrocarbons measured on all three platforms are in good agreement and are generally well correlated with carbon monoxide (CO), indicating the prevalence of on-road VOC emission sources throughout the SoCAB. Offshore measurements aboard the ship and aircraft are used to characterize the air mass composition as a function of the land/sea-breeze effect. VOC ratios and other trace gases are used to identify air masses containing relatively fresh emissions that were often associated with offshore flow and re-circulated continental air associated with onshore flow conditions. With the prevailing southwesterly airflow pattern in the LAB throughout the daytime, the Pasadena ground site effectively functions as a receptor site and is used to characterize primary VOC emissions from downtown Los Angeles and to identify the corresponding secondary oxidation products. The chemical evolution of air masses as a function of the time of day is investigated in order to determine the relative impacts of primary emissions vs. secondary VOC products on OH reactivity and potential SOA formation. The reactivity of VOCs with the hydroxyl radical (OH) at the Pasadena site was dominated by the light hydrocarbons, isoprene, and oxygenated VOCs including aldehydes (secondary products) and alcohols (primary anthropogenic emissions). Toluene and benzaldehyde, both of which are associated with primary anthropogenic emissions, are the predominant VOC precursors to the

  20. Do time-averaged, whole-building, effective volatile organic compound (VOC) emissions depend on the air exchange rate? A statistical analysis of trends for 46 VOCs in U.S. offices.

    PubMed

    Rackes, A; Waring, M S

    2016-08-01

    We used existing data to develop distributions of time-averaged air exchange rates (AER), whole-building 'effective' emission rates of volatile organic compounds (VOC), and other variables for use in Monte Carlo analyses of U.S. offices. With these, we explored whether long-term VOC emission rates were related to the AER over the sector, as has been observed in the short term for some VOCs in single buildings. We fit and compared two statistical models to the data. In the independent emissions model (IEM), emissions were unaffected by other variables, while in the dependent emissions model (DEM), emissions responded to the AER via coupling through a conceptual boundary layer between the air and a lumped emission source. For 20 of 46 VOCs, the DEM was preferable to the IEM and emission rates, though variable, were higher in buildings with higher AERs. Most oxygenated VOCs and some alkanes were well fit by the DEM, while nearly all aromatics and halocarbons were independent. Trends by vapor pressure suggested multiple mechanisms could be involved. The factors of temperature, relative humidity, and building age were almost never associated with effective emission rates. Our findings suggest that effective emissions in real commercial buildings will be difficult to predict from deterministic experiments or models.

  1. Occupational hygiene in terms of volatile organic compounds (VOCs) and bioaerosols at two solid waste management plants in Finland.

    PubMed

    Lehtinen, Jenni; Tolvanen, Outi; Nivukoski, Ulla; Veijanen, Anja; Hänninen, Kari

    2013-04-01

    Factors affecting occupational hygiene were measured at the solid waste transferring plant at Hyvinkää and at the optic separation plant in Hämeenlinna. Measurements consisted of volatile organic compounds (VOCs) and bioaerosols including microbes, dust and endotoxins. The most abundant compounds in both of the plants were aliphatic and aromatic hydrocarbons, esters of carboxylic acids, ketones and terpenes. In terms of odour generation, the most important emissions were acetic acid, 2,3-butanedione, ethyl acetate, alpha-pinene and limonene due to their low threshold odour concentrations. At the optic waste separation plant, limonene occurred at the highest concentration of all single compounds of identified VOCs. The concentration of any single volatile organic compound did not exceed the occupational exposure limit (OEL) concentration. However, 2,3-butanedione as a health risk compound is discussed based on recent scientific findings linking it to lung disease. Microbe and dust concentrations were low at the waste transferring plant. Only endotoxin concentrations may cause health problems; the average concentration inside the plant was 425 EU/m(3) which clearly exceeded the threshold value of 90 EU/m(3). In the wheel loader cabin the endotoxin concentrations were below 1 EU/m(3). High microbial and endotoxin concentrations were measured in the processing hall at the optic waste separation plant. The average concentration of endotoxins was found to be 10,980 EU/m(3), a concentration which may cause health risks. Concentrations of viable fungi were quite high in few measurements in the control room. The most problematic factor was endotoxins whose average measured concentrations was 4853 EU/m(3).

  2. Application of inverse dispersion model for estimating volatile organic compounds emitted from the offshore industrial park

    NASA Astrophysics Data System (ADS)

    Tsai, M.; Lee, C.; Yu, H.

    2013-12-01

    In the last 20 years, the Yunlin offshore industrial park has significantly contributed to the economic development of Taiwan. Its annual production value has reached almost 12 % of Taiwan's GDP in 2012. The offshore industrial park also balanced development of urban and rural in areas. However, the offshore industrial park is considered the major source of air pollution to nearby counties, especially, the emission of Volatile Organic Compounds(VOCs). Studies have found that exposures to high level of some VOCs have caused adverse health effects on both human and ecosystem. Since both health and ecological effects of air pollution have been the subject of numerous studies in recent years, it is a critical issue in estimating VOCs emissions. Nowadays emission estimation techniques are usually used emissions factors in calculation. Because the methodology considered totality of equipment activities based on statistical assumptions, it would encounter great uncertainty between these coefficients. This study attempts to estimate VOCs emission of the Yunlin Offshore Industrial Park using an inverse atmospheric dispersion model. The inverse modeling approach will be applied to the combination of dispersion modeling result which input a given one-unit concentration and observations at air quality stations in Yunlin. The American Meteorological Society-Environmental Protection Agency Regulatory Model (AERMOD) is chosen as the tool for dispersion modeling in the study. Observed concentrations of VOCs are collected by the Taiwanese Environmental Protection Administration (TW EPA). In addition, the study also analyzes meteorological data including wind speed, wind direction, pressure and temperature etc. VOCs emission estimations from the inverse atmospheric dispersion model will be compared to the official statistics released by Yunlin Offshore Industrial Park. Comparison of estimated concentration from inverse dispersion modeling and official statistical concentrations will

  3. Indoor air quality (IAQ) assessment in a multistorey shopping mall by high-spatial-resolution monitoring of volatile organic compounds (VOC).

    PubMed

    Amodio, M; Dambruoso, P R; de Gennaro, Gianluigi; de Gennaro, L; Loiotile, A Demarinis; Marzocca, A; Stasi, F; Trizio, L; Tutino, M

    2014-12-01

    In order to assess indoor air quality (IAQ), two 1-week monitoring campaigns of volatile organic compounds (VOC) were performed in different areas of a multistorey shopping mall. High-spatial-resolution monitoring was conducted at 32 indoor sites located in two storehouses and in different departments of a supermarket. At the same time, VOC concentrations were monitored in the mall and parking lot area as well as outdoors. VOC were sampled at 48-h periods using diffusive samplers suitable for thermal desorption. The samples were then analyzed with gas chromatography-mass spectrometry (GC-MS). The data analysis and chromatic maps indicated that the two storehouses had the highest VOC concentrations consisting principally of terpenes. These higher TVOC concentrations could be a result of the low efficiency of the air exchange and intake systems, as well as the large quantity of articles stored in these small spaces. Instead, inside the supermarket, the food department was the most critical area for VOC concentrations. To identify potential emission sources in this department, a continuous VOC analyzer was used. The findings indicated that the highest total VOC concentrations were present during cleaning activities and that these activities were carried out frequently in the food department. The study highlights the importance of conducting both high-spatial-resolution monitoring and high-temporal-resolution monitoring. The former was able to identify critical issues in environments with a complex emission scenario while the latter was useful in interpreting the dynamics of each emission source.

  4. Effect of habitat and age on variations in volatile organic compound (VOC) emissions from Quercus ilex and Pinus pinea

    NASA Astrophysics Data System (ADS)

    Street, R. A.; Owen, S.; Duckham, S. C.; Boissard, C.; Hewitt, C. N.

    A dynamic branch enclosure was used to measure emission rates of volatile organic compounds (VOCs) under field conditions from two common native Mediterranean species, Quercus ilex and Pinus pinea. In addition to α-pinene, β-pinene, sabinene, limonene and cineole, a suite of lesser known compounds were tentatively identified including cis- and trans-ocimene, cis- and trans-linalool oxide and sabinaketone. Emissions of isoprene from Quercus ilex were insignificant in comparison to those of the monoterpenes and were not detected from Pinus pinea. Variability in emission rates between two habitats, the forest and the dunes, were assessed for Quercus ilex. Temperature sensitivities of emissions and total summed emission rates from Quercus ilex were clearly related to environmental conditions. Emission rates from Pinus pinea showed great variability, but differences between normalised mean emission rates from mature forest and young plantation trees may be significant. Existing emission rate models were found to inadequately describe the observed data.

  5. VOC emissions from wet toner photocopy machines

    SciTech Connect

    Shepherd, J.L.; Howard, C.L.; Leto, B.J.

    1997-12-31

    Indoor air pollution in office buildings affects millions of American workers every day. Potential sources of office indoor air pollution are photocopiers which emit volatile organic compounds (VOCs) during operation. A photocopier`s toner and dispersant contain heavy-treated naphtha, a mixture consisting primarily of decane, which is known to be toxic to humans. An experimental study was completed to characterize VOC emissions from a photocopier located on campus at the University of Texas at Austin. Experiments were completed to estimate the air turnover rate in the room, the VOC concentration in the room during photocopier operation, and a typical daily concentration profile. Based on these experiments, two emissions models were developed: (1) a mass balance on VOC concentration in the room, and (2) a mass balance on the amount of toner and dispersant used per copy. Room ventilation rate was determined to be approximately 1.5 air exchanges per hour. Photocopier emission rates were measured to be from 2 g/min to 9 g/min based on VOC concentration in the room, and were calculated to be 5.4 g/min based on toner and dispersant consumption. These high emission rates of potentially harmful VOCs indicate a need for implementation of measures to protect the health of those utilizing wet toner photocopy machines on a regular basis.

  6. Using Comprehensive Two-dimensional Gas Chromatography (GCxGC) for the Analysis of Volatile Organic Compounds (VOCs)

    NASA Astrophysics Data System (ADS)

    Lidster, R. T.; Hamilton, J. F.; Lewis, A. C.; Lee, J. D.; Hopkins, J. R.; Punjabi, S.

    2012-04-01

    Volatile organic compounds (VOC) play an important role in atmospheric chemistry through their contribution to the formation of ozone and secondary organic aerosol, both of which may lead to human health impacts. VOC monitoring and quantification has traditionally used techniques like gas chromatography and mass spectrometry, with methods developed to target specific groups of compounds. However studies have shown that in some locations the VOC loading in the atmosphere is not fully accounted for. Comprehensive two-dimensional Gas chromatography (GC-GC) utilises two columns coupled via a modulator and can give rise to significant increases in resolution and peak capacity. Used in combination with mass spectrometry it makes a powerful tool for complex sample analysis. Unfortunately GC-GC has found only limited application in atmospheric chemistry due to the instrument size, expense, power consumption and cryogen requirement. GC-GC-TOF/MS has been used to analyse Whole Air Samples (WAS) collected onboard the FAAM research aircraft as part of the "ROle of Nighttime chemistry in controlling the Oxidising Capacity of the AtmOsphere" (RONOCO) campaign. RONOCO studied the transformation of pollutants during nightime over the UK and North Sea. GCxGC results have shown good agreement with an established GC-FID instrument and the comprehensive analysis has allowed for the identification and quantification of additional species not covered by the GC-FID system. The higher molecular weight aromatic compounds detected showed a strong correlation with toluene and this has enabled the calculation of proportionally factors. The additional reactive carbon identified using GC-GC is calculated to provide a large OH sink and may account for some of the missing reactivity seen in previous studies. A number of additional NO3 sink compounds were also identified, although their impact is likely to be small due to their reactivity. Further work has also been carried out on the development

  7. Nanotechnology in environmental remediation: degradation of volatile organic compounds (VOCs) over visible-light-active nanostructured materials.

    PubMed

    Selvaraj, Rengaraj; Al-Kindy, Salma M Z; Silanpaa, Mika; Kim, Younghun

    2014-01-01

    Volatile organic compounds (VOCs) are major pollutants and are considered to be one of the most important contaminants generated by human beings living in urban and industrial areas. Methyl tert-butyl ether (MTBE) is a VOC that has been widely used as a gasoline additive to reduce VOC emissions from motor vehicles. However, new gasoline additives like MTBE are having negative environmental impacts. Recent survey reports clearly show that groundwater is often polluted owing to leakage of petroleum products from underground storage tanks. MTBE is highly soluble in water (e.g., 0.35-0.71 M) and has been detected at high concentrations in groundwater. The presence of MTBE in groundwater poses a potential health problem. The documented effects of MTBE exposure are headaches, vomiting, diarrhea, fever, cough, muscle aches, sleepiness, disorientation, dizziness, and skin and eye irritation. To address these problems, photocatalytic treatment is the preferred treatment for polluted water. In the present work, a simple and template-free solution phase synthesis method has been developed for the preparation of novel cadmium sulfide (CdS) hollow microspheres using cadmium nitrate and thioacetamide precursors. The synthesized products have been characterized by a variety of methods, including X-ray powder diffraction, high-resolution scanning electron microscopy (HR-SEM), X-ray photoelectron spectroscopy, and UV-visible diffused reflectance spectroscopy. The HR-SEM measurements revealed the spherical morphology of the CdS microspheres, which evolved by the oriented aggregation of the primary CdS nanocrystals. Furthermore, studies of photocatalytic activity revealed that the synthesized CdS hollow microspheres exhibit an excellent photocatalytic performance in rapidly degrading MTBE in aqueous solution under visible light illumination. These results suggest that CdS microspheres will be an interesting candidate for photocatalytic detoxification studies under visible light

  8. δ13C of volatile organic compounds (VOCS) in airborne samples by thermal desorption-gas chromatography-isotope ratio-mass spectrometry (TD-GC-IR-MS)

    NASA Astrophysics Data System (ADS)

    Turner, Nicole; Jones, Mark; Grice, Kliti; Dawson, Daniel; Ioppolo-Armanios, Marisa; Fisher, Steven J.

    This paper is a preliminary investigation into the use of a thermal desorption-gas chromatography-isotope ratio mass spectrometry (TD-GC-IR-MS) method to determine stable carbon isotopic compositions ( δ13C) of low molecular-weight volatile organic compounds (VOCs) in airborne samples (e.g. industrial and car exhaust emissions) as a means of differentiating their sources in the environment. A TD-GC-IR-MS method for obtaining δ13C of VOCs (benzene, toluene, chlorobenzene, ethylbenzene, m-xylene and propylbenzene) in air samples has been optimised, and is proven to be both reproducible and linear. The δ13C of the VOC standards was found to be comparable (within analytical error) to that obtained from direct GC-IR-MS analysis. This novel method of VOC analysis is valuable in environmental and forensic investigations.

  9. Assessment of a groundwater contamination with vinyl chloride (VC) and precursor volatile organic compounds (VOC) by use of a geographical information system (GIS).

    PubMed

    Kistemann, Thomas; Hundhausen, Joachim; Herbst, Susanne; Classen, Thomas; Färber, Harald

    2008-07-01

    Regarding the health effects of volatile organic compounds (VOC) and their decomposition products (particularly vinyl chloride (VC)) under chronic low-dose exposure, VOC groundwater contaminations are seen to be an ongoing public health issue. This article presents results of a long-term investigation surveying VOC and VC groundwater contamination upstream of a large groundwater works in Cologne, Germany. For 10 years a contaminated aquifer has been monitored for different VOC and for VC. In total, 255 samples have been taken to assess both the 3-dimensional distribution and the temporal dynamics of the contaminants. VOC and VC precursor substances have been measured by means of pentane-liquid-liquid-extraction, GC and ECD, VC by means of derivatisation to 1,2 dibromochloroethane, GC, ECD, and by purge and trap technique and GC-MS-coupling. For spatial analysis all test results and additional hydrogeological attribute data have been transferred to a GIS. The spatial VOC distribution has been assessed by use of kriging interpolation indicating a decrease of the initial contaminants in time. A cluster analysis allowed to distinguish several independent contaminations within the large contamination area. The VC contamination was increasing. Anaerobic microbial dechlorination of VOC and subsequent VC accumulation were seen to be as credible from several indications (VC presence, downstream change of tetra/trichloroethylene-ratio and anaerobic conditions in the aquifer, high Fe(2+)- and Mn(2+)-concentrations). There was no statistically significant vertical differentiation of VOC and VC concentrations. The VOC load within the different water protection zones of the waterworks could be assessed.

  10. Biogenic VOC and Climate

    NASA Astrophysics Data System (ADS)

    Guenther, A. B.

    2014-12-01

    Secondary organic aerosol (SOA) and ozone are short-lived contributors to radiative forcing that can drive relatively rapid changes in climate. They are not emitted into the atmosphere but are formed from precursors including biogenic volatile organic compounds (BVOC) that are emitted from terrestrial ecosystems. BVOC can also impact longer-lived climate-relevant compounds by acting as a sink for the oxidants that remove moderately reactive gases such as methane and by being a source of carbon dioxide. Emissions of BVOC are highly temperature sensitive, and some also respond to light, and so there is a potential feedback coupling between climate and BVOC emissions. Another potential feedback is associated with the water cycle since SOA can influence precipitation by serving as cloud condensation nuclei and because VOC emissions are sensitive to water availability. Anthropogenic air pollutants add to the complexity of this coupled system by enhancing the production of ozone and SOA from BVOC. The role of BVOC in the land-atmosphere-climate system and potential feedback couplings is conceptually clear but developing an accurate quantitative representation is challenging. Our current understanding of the role of BVOC in the climate system and potential feedback couplings will be presented and the major uncertainties will be discussed. Advances in observations for constraining models, including long-term measurements and recent multi-scale studies, will be presented and priorities for continued advances will be discussed.

  11. Reducing VOC Press Emission from OSB Manufacturing

    SciTech Connect

    Dr. Gary D. McGinnis; Laura S. WIlliams; Amy E. Monte; Jagdish Rughani: Brett A. Niemi; Thomas M. Flicker

    2001-12-31

    Current regulations require industry to meet air emission standards with regard to particulates, volatile organic compounds (VOCs), hazardous air pollutants (HAPs) and other gases. One of many industries that will be affected by the new regulations is the wood composites industry. This industry generates VOCs, HAPs, and particulates mainly during the drying and pressing of wood. Current air treatment technologies for the industry are expensive to install and operate. As regulations become more stringent, treatment technologies will need to become more efficient and cost effective. The overall objective of this study is to evaluate the use of process conditions and chemical additives to reduce VOC/HAPs in air emitted from presses and dryers during the production of oriented strand board.

  12. Matrix effect on the performance of headspace solid phase microextraction method for the analysis of target volatile organic compounds (VOCs) in environmental samples.

    PubMed

    Higashikawa, Fábio S; Cayuela, Maria Luz; Roig, Asunción; Silva, Carlos A; Sánchez-Monedero, Miguel A

    2013-11-01

    Solid phase microextraction (SPME) is a fast, cheap and solvent free methodology widely used for environmental analysis. A SPME methodology has been optimized for the analysis of VOCs in a range of matrices covering different soils of varying textures, organic matrices from manures and composts from different origins, and biochars. The performance of the technique was compared for the different matrices spiked with a multicomponent VOC mixture, selected to cover different VOC groups of environmental relevance (ketone, terpene, alcohol, aliphatic hydrocarbons and alkylbenzenes). VOC recovery was dependent on the nature itself of the VOC and the matrix characteristics. The SPME analysis of non-polar compounds, such as alkylbenzenes, terpenes and aliphatic hydrocarbons, was markedly affected by the type of matrix as a consequence of the competition for the adsorption sites in the SPME fiber. These non-polar compounds were strongly retained in the biochar surfaces limiting the use of SPME for this type of matrices. However, this adsorption capacity was not evident when biochar had undergone a weathering/aging process through composting. Polar compounds (alcohol and ketone) showed a similar behavior in all matrices, as a consequence of the hydrophilic characteristics, affected by water content in the matrix. SPME showed a good performance for soils and organic matrices especially for non-polar compounds, achieving a limit of detection (LD) and limit of quantification (LQ) of 0.02 and 0.03 ng g(-1) for non-polar compounds and poor extraction for more hydrophilic and polar compounds (LD and LQ higher 310 and 490 ng g(-1)). The characteristics of the matrix, especially pH and organic matter, had a marked impact on SPME, due to the competition of the analytes for active sites in the fiber, but VOC biodegradation should not be discarded in matrices with active microbial biomass.

  13. Volatile Organic Compound (VOC) Analysis For Disease Detection: Proof Of Principle For Field Studies Detecting Paratuberculosis And Brucellosis

    NASA Astrophysics Data System (ADS)

    Knobloch, Henri; Köhler, Heike; Nicola, Commander; Reinhold, Petra; Turner, Claire; Chambers, Mark

    2009-05-01

    A proof of concept investigation was performed to demonstrate that two independent infectious diseases of cattle result in different patterns of volatile organic compounds (VOC) in the headspace of serum samples detectable using an electronic nose (e-nose). A total of 117 sera from cattle naturally infected with Mycobacterium avium subsp. paratuberculosis (paraTB, n = 43) or Brucella sp. (n = 26) and sera from corresponding control animals (n = 48) were randomly and analysed blind to infection status using a ST214 e-nose (Scensive Ltd, Leeds, UK). Samples were collected under non-standardised conditions on different farms from the UK (brucellosis) and Germany (paraTB). The e-nose could differentiate the sera from brucellosis infected, paraTB infected and healthy animals at the population level, but the technology used was not suitable for determination of the disease status of individual animals. Nevertheless, the data indicate that there are differences in the sensor responses depending on the disease status, and therefore, it shows the potential of VOC analysis from serum headspace samples for disease detection.

  14. Constraints on the sources and impacts of volatile organic compounds (VOCs) over North America from tall tower measurements

    NASA Astrophysics Data System (ADS)

    Hu, Lu

    This dissertation presents the first-ever in-situ tall tower measurements of volatile organic compound (VOC) concentrations. The data span August 2009 through July 2012, and provide new constraints on seasonal and long-term controls on VOC sources and their atmospheric effects. The 200 m sampling height provides a large-scale footprint, while the tall tower location, near the intersection of the main North American ecosystems and at times downwind of the Twin Cities, affords information on natural emissions from some of the most important US landscapes as well as on anthropogenic sources. I interpret the dataset using an atmospheric chemical transport model (GEOS-Chem CTM), with a focus on several key atmospheric VOCs. This dissertation finds that current models underestimate methanol emission rates for younger versus older leaves. This biased seasonality means that the photochemical role for methanol early in the growing season is presently underestimated. A Bayesian inverse analysis of the tall tower observations reveals that the prior estimate of North American anthropogenic acetone sources (based on the US EPA's NEI05 inventory) is accurate to within 20%. However, biogenic acetone emissions from broadleaf trees, shrubs, and herbaceous plants are presently underestimated (˜37%), while emissions from needleleaf trees plus secondary production from biogenic precursors are overestimated by a similar amount (˜40%). Model-measurement comparisons imply that isoprene emissions in the immediate vicinity of the tall tower are accurately captured by the MEGANv2.1 biogenic inventory, but that larger-scale regional emissions are underestimated, reflecting the heterogeneous land cover in this transitional landscape. Isoprene emissions play a key role in seasonal shifts between VOC-limited chemistry in the spring and fall and NOx-limited or transitional chemistry in the summer. A Bayesian inverse analysis based on the tall tower measurements suggests that: i) the RETRO

  15. Fragranced consumer products: Chemicals emitted, ingredients unlisted

    SciTech Connect

    Steinemann, Anne C.; MacGregor, Ian C.; Gordon, Sydney M.; Gallagher, Lisa G.; Davis, Amy L.; Ribeiro, Daniel S.; Wallace, Lance A.

    2011-04-15

    Fragranced consumer products are pervasive in society. Relatively little is known about the composition of these products, due to lack of prior study, complexity of formulations, and limitations and protections on ingredient disclosure in the U.S. We investigated volatile organic compounds (VOCs) emitted from 25 common fragranced consumer products-laundry products, personal care products, cleaning supplies, and air fresheners-using headspace analysis with gas chromatography/mass spectrometry (GC/MS). Our analysis found 133 different VOCs emitted from the 25 products, with an average of 17 VOCs per product. Of these 133 VOCs, 24 are classified as toxic or hazardous under U.S. federal laws, and each product emitted at least one of these compounds. For 'green' products, emissions of these compounds were not significantly different from the other products. Of all VOCs identified across the products, only 1 was listed on any product label, and only 2 were listed on any material safety data sheet (MSDS). While virtually none of the chemicals identified were listed, this nonetheless accords with U.S. regulations, which do not require disclosure of all ingredients in a consumer product, or of any ingredients in a mixture called 'fragrance.' Because the analysis focused on compounds emitted and listed, rather than exposures and effects, it makes no claims regarding possible risks from product use. Results of this study contribute to understanding emissions from common products, and their links with labeling and legislation.

  16. Blue light emitting Ir(III) compounds for OLEDs - new insights into ancillary ligand effects on the emitting triplet state.

    PubMed

    Rausch, Andreas F; Thompson, Mark E; Yersin, Hartmut

    2009-05-21

    The sky-blue emitting phosphorescent compound Ir(4,6-dFppy)(2)(acac) (FIracac) doped into different matrices is studied under ambient conditions and at cryogenic temperatures on the basis of broadband and high-resolution emission spectra. The emitting triplet state is found to be largely of metal-to-ligand charge transfer (MLCT) character. It is observed that different polycrystalline and amorphous hosts distinctly affect the properties of the triplet. Moreover, a comparison of FIracac with the related Ir(4,6-dFppy)(2)(pic) (FIrpic), differing only by the ancillary ligand, reveals obvious changes of properties of the emitting state. These observations are explained by different effects of acac and pic on the Ir(III) d-orbitals. In particular, the occupied frontier orbitals, strongly involving the t(2g)-manifold, and their splitting patterns are modified differently. This influences spin-orbit coupling (SOC) of the emitting triplet state to higher-lying (1,3)MLCT states. As a consequence, zero-field splittings, radiative decay rates, and phosphorescence quantum yields are changed. The important effects of SOC are discussed qualitatively and are related to the emission properties of the individual triplet substates, as determined from highly resolved spectra. The results allow us to gain a better understanding of the impact of SOC on the emission properties with the aim to develop more efficient triplet emitters for OLEDs.

  17. Review of unsaturated-zone transport and attenuation of volatile organic compound (VOC) plumes leached from shallow source zones.

    PubMed

    Rivett, Michael O; Wealthall, Gary P; Dearden, Rachel A; McAlary, Todd A

    2011-04-25

    Reliable prediction of the unsaturated zone transport and attenuation of dissolved-phase VOC (volatile organic compound) plumes leached from shallow source zones is a complex, multi-process, environmental problem. It is an important problem as sources, which include solid-waste landfills, aqueous-phase liquid discharge lagoons and NAPL releases partially penetrating the unsaturated zone, may persist for decades. Natural attenuation processes operating in the unsaturated zone that, uniquely for VOCs includes volatilisation, may, however, serve to protect underlying groundwater and potentially reduce the need for expensive remedial actions. Review of the literature indicates that only a few studies have focused upon the overall leached VOC source and plume scenario as a whole. These are mostly modelling studies that often involve high strength, non-aqueous phase liquid (NAPL) sources for which density-induced and diffusive vapour transport is significant. Occasional dissolved-phase aromatic hydrocarbon controlled infiltration field studies also exist. Despite this lack of focus on the overall problem, a wide range of process-based unsaturated zone - VOC research has been conducted that may be collated to build good conceptual model understanding of the scenario, particularly for the much studied aromatic hydrocarbons and chlorinated aliphatic hydrocarbons (CAHs). In general, the former group is likely to be attenuated in the unsaturated zone due to their ready aerobic biodegradation, albeit with rate variability across the literature, whereas the fate of the latter is far less likely to be dominated by a single mechanism and dependent upon the relative importance of the various attenuation processes within individual site - VOC scenarios. Analytical and numerical modelling tools permit effective process representation of the whole scenario, albeit with potential for inclusion of additional processes - e.g., multi-mechanistic sorption phase partitioning, and provide

  18. Source apportionment of ambient VOCS in Mumbai city

    NASA Astrophysics Data System (ADS)

    Srivastava, Anjali

    Air pollution kills almost half a million Asians every year. Most of this pollution is emitted from buses, trucks, motorcycles and other forms of transport. As Asia's cities continue to expand, the rising number of vehicles has resulted in even greater pollution. Amongst the measures available to control, vehicular emission was engine modification, catalytic converters and fuel modifications. Some of these have led to emissions of some hazardous air pollutants (HAP) like volatile organic compounds (VOCs). VOC emission is an area needing attention in air quality management. This paper discusses a study on VOC concentration at major sources like traffic junction, residential area, commercial areas, industrial areas and petrol pumps in Mumbai city. CMB8 Model has been used to apportion VOCs in Mumbai city. It was observed that evaporative emissions dominate in Mumbai. In order to control VOCs in air the management strategy should thus focus on cost effective vapor recovery systems at refueling stations and in vehicles. Effective inspection and maintenance programme can reduce evaporative and exhaust VOC emissions. Modifying certain fuel parameters, like reducing benzene content in petrol will as well reduce VOC content in air. The benzene content in petrol was 3% in the year 2001 in Mumbai. Adulteration also results in high levels of VOCs in air.

  19. Volatile organic compounds (VOC) and their contribution to the enhancement of photooxidants in the Greater Athens Area under Mediterranean climate conditions

    SciTech Connect

    Rappenglueck, B.; Fabian, P.; Kalabokas, P.; Viras, L.G.; Ziomas, I.C.

    1996-12-31

    Volatile organic compounds (VOC) play an important role in photochemical processes in the lower troposphere. In presence of nitrogen oxides VOC largely contribute to the build-up of ozone and PAN, especially during sunny and warm weather conditions. During the period from 20 August until 20 September 1994 a comprehensive campaign entitled Mediterranean Campaign of Photochemical Tracers--Transport and Evolution (MEDCAPHOT-TRACE) took place in the GAA covering a wide range of simultaneous measurements of meteorological parameters and air chemical compounds including various experimental equipment such as LIDAR, DOAS, tethered balloon soundings, aircraft measurements and ground-based devices. Here the authors will report about VOC-measurements that were carried out on a quasi-continuous basis by two GC/FID-systems at two sites in the GAA.

  20. Surface emission determination of volatile organic compounds (VOC) from a closed industrial waste landfill using a self-designed static flux chamber.

    PubMed

    Gallego, E; Perales, J F; Roca, F J; Guardino, X

    2014-02-01

    Closed landfills can be a source of VOC and odorous nuisances to their atmospheric surroundings. A self-designed cylindrical air flux chamber was used to measure VOC surface emissions in a closed industrial landfill located in Cerdanyola del Vallès, Catalonia, Spain. The two main objectives of the study were the evaluation of the performance of the chamber setup in typical measurement conditions and the determination of the emission rates of 60 different VOC from that industrial landfill, generating a valuable database that can be useful in future studies related to industrial landfill management. Triplicate samples were taken in five selected sampling points. VOC were sampled dynamically using multi-sorbent bed tubes (Carbotrap, Carbopack X, Carboxen 569) connected to SKC AirCheck 2000 pumps. The analysis was performed by automatic thermal desorption coupled with a capillary gas chromatograph/mass spectrometry detector. The emission rates of sixty VOC were calculated for each sampling point in an effort to characterize surface emissions. To calculate average, minimum and maximum emission values for each VOC, the results were analyzed by three different methods: Global, Kriging and Tributary area. Global and Tributary area methodologies presented similar values, with total VOC emissions of 237 ± 48 and 222 ± 46 g day(-1), respectively; however, Kriging values were lower, 77 ± 17 gd ay(-1). The main contributors to the total emission rate were aldehydes (nonanal and decanal), acetic acid, ketones (acetone), aromatic hydrocarbons and alcohols. Most aromatic hydrocarbon (except benzene, naphthalene and methylnaphthalenes) and aldehyde emission rates exhibited strong correlations with the rest of VOC of their family, indicating a possible common source of these compounds. B:T ratio obtained from the emission rates of the studied landfill suggested that the factors that regulate aromatic hydrocarbon distributions in the landfill emissions are different from the ones

  1. Volatile Organic Compounds (VOCs) onboard the HALO research aircraft during OMO-ASIA

    NASA Astrophysics Data System (ADS)

    Safadi, Layal; Neumaier, Marco; Fischbeck, Garlich; Zahn, Andreas

    2016-04-01

    We report on first results of VOC measurements during the OMO-Asia campaign that took place in summer 2015 on Cyprus and on the island of Gan (Maldives) to study the free-radical chemistry at higher altitudes during the Asian summer monsoon. The deployed instrument (KMS = Karlsruhe Mass Spectrometer) is based on a commercial PTRMS from Ionicon and was strongly modified for the use onboard the research aircraft HALO (a modified Gulfstream GV-550 having a ceiling altitude of ~15.5 km). By the construction of an aluminum vacuum system, the development of largely custom-made electronics and the use of light-weight pumps, the weight was reduced to ~55 kg compared to 120-130 kg of the commercial instrument. The KMS is in addition very robust and field-compliant. Before OMO-Asia the HALO payload was tested first during a technical field campaign OMO-EU which took place in Oberpfaffenhofen (Germany) in winter 2015. During OMO-Asia the instrument was calibrated before and after each flight by diluting an external gas standard (Apel-Riemer Environmental, Inc. Denver, Colorado) containing ~1 ppm of 10 VOCs. The determined sensitivity for acetone was ~380 cps/ppb showing a variation of ±5% over a period of 8 weeks. The detection limit amounted to ~35 ppt for acetone at an integration time of 6 s. The measurements during all together 17 flights took place over a wide range of Asia, including Saudi Arabia, Bahrain, Oman and Sri Lanka. Referring to the meteorological forecasts of carbon monoxide (CO), remnant of the Asia monsoon outflow was measured during some flights (e.g. over Oman). Acetone mixing ratios of up to ~1500 ppt and up to ~100 ppt of benzene were measured in the outflow of the plume. The gathered data shows a good correlation with the measurements taken with other instruments (e.g. CO measurements by Max Planck Institute for Chemistry). The poster will describe the instrument and the main features derived.

  2. Determination of volatile organic compounds (VOCs) from wrapping films and wrapped PDO Italian cheeses by using HS-SPME and GC/MS.

    PubMed

    Panseri, Sara; Chiesa, Luca Maria; Zecconi, Alfonso; Soncini, Gabriella; De Noni, Ivano

    2014-06-25

    Nowadays food wrapping assures attractive presentation and simplifies self-service shopping. Polyvinylchloride (PVC)- and polyethylene (PE)-based cling-films are widely used worldwide for wrapping cheeses. For this purpose, films used in retail possess suitable technical properties such as clinginess and unrolling capacity, that are achieved by using specific plasticizers during their manufacturing process. In the present study, the main VOCs of three cling-films (either PVC-based or PE-based) for retail use were characterized by means of Solid-Phase Micro-Extraction and GC/MS. In addition, the effects of cling film type and contact time on the migration of VOCs from the films to four different PDO Italian cheeses during cold storage under light or dark were also investigated. Among the VOCs isolated from cling-films, PVC released 2-ethylhexanol and triacetin. These compounds can likely be considered as a "non-intentionally added substance". These same compounds were also detected in cheeses wrapped in PVC films with the highest concentration found after 20 days storage. The PE cling-film was shown to possess a simpler VOC profile, lacking some molecules peculiar to PVC films. The same conclusions can be drawn for cheeses wrapped in the PE cling-film. Other VOCs found in wrapped cheeses were likely to have been released either by direct transfer from the materials used for the manufacture of cling-films or from contamination of the films. Overall, HS-SPME is shown to be a rapid and solvent free technique to screen the VOCs profile of cling-films, and to detect VOCs migration from cling-films to cheese under real retail storage conditions.

  3. Operation of a two-stage treatment train for the remediation of volatile organic compounds (VOCs) from a complex air stream

    SciTech Connect

    Manninen, M.R.; Kleinheinz, G.T.; Niemi, B.A.; Hose, J.T.

    1999-07-01

    The use of aqueous biological systems to remove contaminants from waste streams has been well documented. However, in complex waste streams containing compounds of varying chemical properties, the use of only one type of treatment system may not be the best alternative. When treating a complex waste stream, the use of treatment trains, or coupled systems, may be advantageous when compared with any single technology. The purpose of this project was to design and operate a treatment train for the effective removal and biodegradation of a complex mixture of VOCs with varying chemical properties. A bench-scale system was designed consisting of a liquid bioreactor coupled to a biofilter for removal of acetone, methanol, methyl ethyl ketone, naphthalene, alpha-pinene, and toluene. The liquid bioreactor contained an aqueous medium and an inert solid support (polystyrene bioballs) which immobilized a characterized microbial population. The biofiltration portion of the system utilized the same microbial inoculum, but employed Douglas fir bark as its solid support. As the air stream bubbled into the liquid bioreactor, the VOCs were made available to the bacteria for destruction in the aqueous medium or on the polystyrene solid support. The fugitive VOCs from the liquid bioreactor were then subsequently treated by the biofiltration unit. The six-compound VOC mixture was added to the air stream via in-line syringe pump injection. Concentrations of the VOC mixture in the main influent air stream, the effluent air stream from the liquid bioreactor, the aqueous medium in the liquid bioreactor, and the effluent air stream from the biofilter were monitored on a regular basis via an on-line gas chromatograph with a flame ionization detector (GC-FID). Successful biodegradation of the complex VOC mixture was accomplished with this treatment train, the average total VOC removal efficiency being 96.2% ({+-}2.6).

  4. Volatile Organic Compounds (VOCs) Measured in the Arctic Aboard the R/V Knorr During ICEALOT 2008: Primary Sources and Evidence of Halogen Oxidation

    NASA Astrophysics Data System (ADS)

    Gilman, J. B.; Kuster, W. C.; Goldan, P. D.; Lerner, B. M.; Williams, E. J.; de Gouw, J. A.

    2008-12-01

    A full suite of gas-phase compounds were measured in-situ aboard the R/V Knorr as part of the International Chemistry Experiment in the Arctic Lower Troposphere (ICEALOT) conducted in March and April of 2008. A wide range of VOCs were measured by a two-channel GC-MS (Gas Chromatograph-Mass Spectrometer) every 30 minutes significantly expanding the spatial and temporal database of these compounds in the Arctic spring-time marine boundary layer. This was done in order to (1) characterize the composition of VOCs over the ice-free regions of the Arctic and to (2) determine the relative impacts of local VOC sources (i.e. oceanic and local point sources) and sinks (i.e. halogen oxidation) in this isolated region. The VOC composition was dominated by relatively long-lived VOCs, such as ethane (median = 2.1 ppbv) and propane (median = 1.3 ppbv), and remained relatively constant throughout the far North Atlantic; however, there were distinct events that displayed significant variability in the measured mixing ratios of some VOCs. One episode is characterized by a 2-10 fold increase in C2-C6 alkanes indicating a primary source of anthropogenic emissions near the Kola Peninsula (Russia). In contrast, a significant decline in certain VOCs is associated with a halogen oxidation episode that occurred during an ozone depletion event (ODE). Halogen oxidation was further evidenced by sharp departures in the [benzene]/[acetylene] and [iso-butane]/[n-butane] ratios which are known to be affected by halogen chemistry.

  5. Predicting the emission of volatile organic compounds from silage systems

    USDA-ARS?s Scientific Manuscript database

    As a precursor to smog, emission of volatile organic compounds (VOCs) to the atmosphere is an environmental concern in some regions. The major VOC emission source from farms is silage, with emissions coming from the silo face, mixing wagon, and feed bunk. The major compounds emitted are alcohols wit...

  6. Light dependency of VOC emissions from selected Mediterranean plant species

    NASA Astrophysics Data System (ADS)

    Owen, S. M.; Harley, P.; Guenther, A.; Hewitt, C. N.

    The light, temperature and stomatal conductance dependencies of volatile organic compound (VOC) emissions from ten plant species commonly found in the Mediterranean region were studied using a fully controlled leaf cuvette in the laboratory. At standard conditions of temperature and light (30°C and 1000 μmol m -2 s -1 PAR), low emitting species ( Arbutus unedo, Pinus halepensis, Cistus incanus, Cistus salvifolius, Rosmarinus officinalis and Thymus vulgaris) emitted between 0.1 and 5.0 μg (C) (total VOCs) g -1 dw h -1, a medium emitter ( Pinus pinea) emitted between 5 and 10 μg (C) g -1 dw h -1 and high emitters ( Cistus monspeliensis, Lavendula stoechas and Quercus sp.) emitted more than 10 μg (C) g -1 dw h -1. VOC emissions from all of the plant species investigated showed some degree of light dependency, which was distinguishable from temperature dependency. Emissions of all compounds from Quercus sp. were light dependent. Ocimene was one of several monoterpene compounds emitted by P. pinea and was strongly correlated to light. Only a fraction of monoterpene emissions from C. incanus exhibited apparent weak light dependency but emissions from this plant species were strongly correlated to temperature. Data presented here are consistent with past studies, which show that emissions are independent of stomatal conductance. These results may allow more accurate predictions of monoterpene emission fluxes from the Mediterranean region to be made.

  7. Automated detection and reporting of Volatile Organic Compounds (VOCs) in complex environments

    SciTech Connect

    Hargis, P.J. Jr.; Preppernau, B.L.; Osbourn, G.C.

    1997-03-01

    This paper describes results from efforts to develop VOC sensing systems based on two complementary techniques. The first technique used a gated channeltron detector for resonant laser-induced multiphoton photoionization detection of trace organic vapors in a supersonic molecular beam. The channeltron was gated using a relatively simple circuit to generate a negative gate pulse with a width of 400 ns (FWHM), a 50 ns turn-on (rise) time, a 1.5 {mu}s turn-off (decay) time, a pulse amplitude of {minus}1000 Volts, and a DC offset adjustable from zero to {minus}1500 Volts. The gated channeltron allows rejection of spurious responses to UV laser light scattered directly into the channeltron and time-delayed ionization signals induced by photoionization of residual gas in the vacuum chamber. Detection limits in the part-per-trillion range have been demonstrated with the gated detector. The second technique used arrays of surface acoustic wave (SAW) devices coated with various chemically selective materials (e.g., polymers, self assembled monolayers) to provide unique response patterns to various chemical analytes. This work focused on polymers, formed by spin casting from solution or by plasma polymerization, as well as on self assembled monolayers. Response from coated SAWs to various concentrations of water, volatile organics, and organophosphonates (chemical warfare agent simulants) were used to provide calibration data. A novel visual empirical region of influence (VIERI) pattern recognition technique was used to evaluate the ability to use these response patterns to correctly identify chemical species. This investigation shows how the VERI technique can be used to determine the best set of coatings for an array, to predict the performance of the array even if sensor responses change due to aging of the coating materials, and to identify unknown analytes based on previous calibration data.

  8. PM2.5 and volatile organic compounds (VOCs) in ambient air: a focus on the effect of meteorology.

    PubMed

    Giakoumi, A; Maggos, Th; Michopoulos, J; Helmis, C; Vasilakos, Ch

    2009-05-01

    PM(2.5) and VOCs (benzene, toluene, m-p-o-xylenes) concentrations were measured in an urban and a suburban site in Athens, Greece, during the period between April and November 2004. This period, which is considered to be the warmer period in Greece, is characterized by the development of sea-breeze over the Attica Basin. Additionally strong Northern, North-eastern winds called "The Etesians", predominate during the summer months (July-August), acting positively to the dispersion of pollutants. In this campaign, 24 days with sea-breeze development were observed, 15 days with northern winds, 6 days with southern winds while the rest of the days presented no specific wind profile. Maximum concentrations of PM(2.5), VOCs and nitrogen oxides, were detected during the days with sea-breeze, while minimum concentrations during the days with northern winds. Ozone was the only pollutant that appeared to have higher concentrations in the background site and not in the city centre, where benzene presented strong negative correlation with ozone, indicating the photochemical reaction of hydrocarbons that lead to the ozone formation. The BTX ratios were similar for both sites and wind profiles, indicating common sources for those pollutants. T/B ratio ranged in low levels, between 3-5 for site A and 2-5 for site B, suggesting vehicles emissions as the main sources of volatile compounds. Finally, the strong correlations of PM(2.5) and benzene concentrations, between the two sampling sites, indicate that both the city centre and the background site, are affected by the same sources, under common meteorological conditions (sea-breeze, northern winds).

  9. Toxic pollutants emitted from thermal decomposition of phthalimide compounds.

    PubMed

    Chen, Kai; Mackie, John C; Wojtalewicz, Dominika; Kennedy, Eric M; Dlugogorski, Bogdan Z

    2011-03-15

    Phthalimide (PI) and tetrahydrophthalimide (THPI) are two structurally similar compounds extensively used as intermediates for the synthesis of variety of industrial chemicals. This paper investigates the thermal decomposition of PI and THPI under oxygen rich to oxygen lean conditions, quantifying the production of toxicants and explaining their formation pathways. The experiments involved a plug flow reactor followed by silica cartridges, activated charcoal trap and a condenser, with the decomposition products identified and quantified by Fourier transform infrared spectroscopy (FTIR), gas chromatography-mass spectrometry (GC-MS) and micro gas chromatography (μGC). The density functional theory (DFT) calculations served to obtain dissociation energies and reaction pathways, to elucidate the reaction mechanism. The oxidation of PI and THPI produced several toxic nitrogen-containing gases and volatile organic compounds, including hydrogen cyanide, isocyanic acid, nitrogen oxides, benzonitrile, maleimide and tentatively identified benzenemethanimine. The detection of dibenzo-p-dioxin (DD) and dibenzofuran (DF) suggests potential formation of the toxic persistent organic pollutants (POPs) in fires involving PI and THPI, in presence of a chlorine source. The oxidation of THPI produced 2-cyclohexen-1-one, a toxic unsaturated ketone. The results of the present study provide the data for quantitative risk assessments of emissions of toxicants in combustion processes involving PI and THPI. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Arabidopsis thaliana as Bioindicator of Fungal VOCs in Indoor Air

    PubMed Central

    Hung, Richard; Yin, Guohua; Klich, Maren A.; Grimm, Casey; Bennett, Joan W.

    2016-01-01

    In this paper, we demonstrate the ability of Arabidopsis thaliana to detect different mixtures of volatile organic compounds (VOCs) emitted by the common indoor fungus, Aspergillus versicolor, and demonstrate the potential usage of the plant as a bioindicator to monitor fungal VOCs in indoor air. We evaluated the volatile production of Aspergillus versicolor strains SRRC 108 (NRRL 3449) and SRRC 2559 (ATCC 32662) grown on nutrient rich fungal medium, and grown under conditions to mimic the substrate encountered in the built environment where fungi would typically grow indoors (moist wallboard and ceiling tiles). Using headspace solid phase microextraction/gas chromatography-mass spectrometry, we analyzed VOC profiles of the two strains. The most abundant compound produced by both strains on all three media was 1-octen-3-ol. Strain SRRC 2559 made several terpenes not detected from strain SRRC 108. Using a split-plate bioassay, we grew Arabidopsis thaliana in a shared atmosphere with VOCs from the two strains of Aspergillus versicolor grown on yeast extract sucrose medium. The VOCs emitted by SRRC 2559 had an adverse impact on seed germination and plant growth. Chemical standards of individual VOCs from the Aspergillus versicolor mixture (2-methyl-1-butanol, 3-methyl-1-butanol, 1-octen-3-ol, limonene, and β-farnesene), and β-caryophyllene were tested one by one in seed germination and vegetative plant growth assays. The most inhibitory compound to both seed germination and plant growth was 1-octen-3-ol. Our data suggest that Arabidopsis is a useful model for monitoring indoor air quality as it is sensitive to naturally emitted fungal volatile mixtures as well as to chemical standards of individual compounds, and it exhibits relatively quick concentration- and duration-dependent responses. PMID:27790067

  11. Summary of state VOC (volatile organic compound) regulations. Volume 2. Group 3 CTG (control technique guidelines) and greater than 100 ton per year non-CTG VOC regulations

    SciTech Connect

    Clark, C.R.; Meardon, K.R.

    1988-05-01

    In April of 1985, EPA published Summary of State VOC Regulations (EPA-450/2-85-003), which summarized regulations for Group I, II, and III CTG's and >100 tpy non-CTG categories as of August 1, 1984. This document updates and expands parts of that publication; specifically, it presents summaries of State and local regulations for Group III CTG's and >100 tpy non-CTG regulations. Information used to compile the document was collected from all 10 EPA regions in early 1987.

  12. Emissions of volatile organic compounds (VOCs) from oil and natural gas activities: compositional comparison of 13 major shale basins via NOAA airborne measurements

    NASA Astrophysics Data System (ADS)

    Gilman, J.; Lerner, B. M.; Aikin, K. C.; De Gouw, J. A.; Koss, A.; Yuan, B.; Warneke, C.; Peischl, J.; Ryerson, T. B.; Holloway, J. S.; Graus, M.; Tokarek, T. W.; Isaacman-VanWertz, G. A.; Sueper, D.; Worsnop, D. R.

    2015-12-01

    The recent and unprecedented increase in natural gas production from shale formations is associated with a rise in the production of non-methane volatile organic compounds (VOCs) including natural gas plant liquids (e.g., ethane, propane, and butanes) and liquid lease condensate (e.g., pentanes, hexanes, aromatics and cycloalkanes). Since 2010, the production of natural gas liquids and the amount of natural gas vented/flared has increased by factors of ~1.28 and 1.57, respectively (U.S. Energy and Information Administration), indicating an increasingly large potential source of hydrocarbons to the atmosphere. Emission of VOCs may affect local and regional air quality due to the potential to form tropospheric ozone and organic particles as well as from the release of toxic species such as benzene and toluene. The 2015 Shale Oil and Natural Gas Nexus (SONGNex) campaign studied emissions from oil and natural gas activities across the central United States in order to better understand their potential air quality and climate impacts. Here we present VOC measurements from 19 research flights aboard the NOAA WP-3D over 11 shale basins across 8 states. Non-methane hydrocarbons were measured using an improved whole air sampler (iWAS) with post-flight analysis via a custom-built gas chromatograph-mass spectrometer (GC-MS). The whole air samples are complimented by higher-time resolution measurements of methane (Picarro spectrometer), ethane (Aerodyne spectrometer), and VOCs (H3O+ chemical ionization mass spectrometer). Preliminary analysis show that the Permian Basin on the New Mexico/Texas border had the highest observed VOC mixing ratios for all basins studied. We will utilize VOC enhancement ratios to compare the composition of methane and VOC emissions for each basin and the associated reactivities of these gases with the hydroxyl radical, OH, as a proxy for potential ozone formation.

  13. Air sampling and analysis method for volatile organic compounds (VOCs) related to field-scale mortality composting operations.

    PubMed

    Akdeniz, Neslihan; Koziel, Jacek A; Ahn, Hee-Kwon; Glanville, Thomas D; Crawford, Benjamin P; Raman, D Raj

    2009-07-08

    In biosecure composting, animal mortalities are so completely isolated during the degradation process that visual inspection cannot be used to monitor progress or the process status. One novel approach is to monitor the volatile organic compounds (VOCs) released by decaying mortalities and to use them as biomarkers of the process status. A new method was developed to quantitatively analyze potential biomarkers--dimethyl disulfide, dimethyl trisulfide, pyrimidine, acetic acid, propanoic acid, 3-methylbutanoic acid, pentanoic acid, and hexanoic acid--from field-scale biosecure mortality composting units. This method was based on collection of air samples from the inside of biosecure composting units using portable pumps and solid phase microextraction (SPME). Among four SPME fiber coatings, 85 microm CAR/PDMS was shown to extract the greatest amount of target analytes during a 1 h sampling time. The calibration curves had high correlation coefficients, ranging from 96 to 99%. Differences between the theoretical concentrations and those estimated from the calibration curves ranged from 1.47 to 20.96%. Method detection limits of the biomarkers were between 11 pptv and 572 ppbv. The applicability of the prepared calibration curves was tested for air samples drawn from field-scale swine mortality composting test units. Results show that the prepared calibration curves were applicable to the concentration ranges of potential biomaker compounds in a biosecure animal mortality composting unit.

  14. The human volatilome: volatile organic compounds (VOCs) in exhaled breath, skin emanations, urine, feces and saliva.

    PubMed

    Amann, Anton; Costello, Ben de Lacy; Miekisch, Wolfram; Schubert, Jochen; Buszewski, Bogusław; Pleil, Joachim; Ratcliffe, Norman; Risby, Terence

    2014-09-01

    Breath analysis is a young field of research with its roots in antiquity. Antoine Lavoisier discovered carbon dioxide in exhaled breath during the period 1777-1783, Wilhelm (Vilém) Petters discovered acetone in breath in 1857 and Johannes Müller reported the first quantitative measurements of acetone in 1898. A recent review reported 1765 volatile compounds appearing in exhaled breath, skin emanations, urine, saliva, human breast milk, blood and feces. For a large number of compounds, real-time analysis of exhaled breath or skin emanations has been performed, e.g., during exertion of effort on a stationary bicycle or during sleep. Volatile compounds in exhaled breath, which record historical exposure, are called the 'exposome'. Changes in biogenic volatile organic compound concentrations can be used to mirror metabolic or (patho)physiological processes in the whole body or blood concentrations of drugs (e.g. propofol) in clinical settings-even during artificial ventilation or during surgery. Also compounds released by bacterial strains like Pseudomonas aeruginosa or Streptococcus pneumonia could be very interesting. Methyl methacrylate (CAS 80-62-6), for example, was observed in the headspace of Streptococcus pneumonia in concentrations up to 1420 ppb. Fecal volatiles have been implicated in differentiating certain infectious bowel diseases such as Clostridium difficile, Campylobacter, Salmonella and Cholera. They have also been used to differentiate other non-infectious conditions such as irritable bowel syndrome and inflammatory bowel disease. In addition, alterations in urine volatiles have been used to detect urinary tract infections, bladder, prostate and other cancers. Peroxidation of lipids and other biomolecules by reactive oxygen species produce volatile compounds like ethane and 1-pentane. Noninvasive detection and therapeutic monitoring of oxidative stress would be highly desirable in autoimmunological, neurological, inflammatory diseases and cancer

  15. Multiple internal standard normalization for improving HS-SPME-GC-MS quantitation in virgin olive oil volatile organic compounds (VOO-VOCs) profile.

    PubMed

    Fortini, Martina; Migliorini, Marzia; Cherubini, Chiara; Cecchi, Lorenzo; Calamai, Luca

    2017-04-01

    The commercial value of virgin olive oils (VOOs) strongly depends on their classification, also based on the aroma of the oils, usually evaluated by a panel test. Nowadays, a reliable analytical method is still needed to evaluate the volatile organic compounds (VOCs) and support the standard panel test method. To date, the use of HS-SPME sampling coupled to GC-MS is generally accepted for the analysis of VOCs in VOOs. However, VOO is a challenging matrix due to the simultaneous presence of: i) compounds at ppm and ppb concentrations; ii) molecules belonging to different chemical classes and iii) analytes with a wide range of molecular mass. Therefore, HS-SPME-GC-MS quantitation based upon the use of external standard method or of only a single internal standard (ISTD) for data normalization in an internal standard method, may be troublesome. In this work a multiple internal standard normalization is proposed to overcome these problems and improving quantitation of VOO-VOCs. As many as 11 ISTDs were used for quantitation of 71 VOCs. For each of them the most suitable ISTD was selected and a good linearity in a wide range of calibration was obtained. Except for E-2-hexenal, without ISTD or with an unsuitable ISTD, the linear range of calibration was narrower with respect to that obtained by a suitable ISTD, confirming the usefulness of multiple internal standard normalization for the correct quantitation of VOCs profile in VOOs. The method was validated for 71 VOCs, and then applied to a series of lampante virgin olive oils and extra virgin olive oils. In light of our results, we propose the application of this analytical approach for routine quantitative analyses and to support sensorial analysis for the evaluation of positive and negative VOOs attributes.

  16. Volatile organic compounds (VOCs) emission characteristics and control strategies for a petrochemical industrial area in middle Taiwan.

    PubMed

    Yen, Chia-Hsien; Horng, Jao-Jia

    2009-11-01

    This study investigated VOC emissions from the largest petrochemical industrial district in Taiwan and recommended some control measures to reduce VOC emissions. In addition to the petrochemical industry, the district encompasses a chemical and fiber industry, a plastics industry and a harbor, which together produce more than 95% of the VOC emissions in the area. The sequence of VOC emission was as follows: components (e.g., valves, flanges, and pumps) (47%) > tanks (29%) > stacks (15%) > wastewater treatment facility (6%) > loading (2%) > flares (1%). Other plants producing high-density polyethylene (HDPE), styrene, ethylene glycol (EG), gas oil, and iso-nonyl-alchol (INA) were measured to determine the VOC leaching in the district. The VOC emissions of these 35 plants (90% of all plants) were less than 100 tons/year. About 74% of the tanks were fixed-roof tanks that leached more VOCs than the other types of tanks. To reduce leaching, the components should be checked periodically, and companies should be required to follow the Taiwan EPA regulations. A VOC emission management system was developed in state implementation plans (SIPs) to inspect and reduce emissions in the industrial district.

  17. The VOC-ozone connection: a grassland case study

    NASA Astrophysics Data System (ADS)

    Wohlfahrt, G.; Hoertnagl, L.; Bamberger, I.; Schnitzhofer, R.; Dunkel, J.; Hammerle, A.; Graus, M.; Hansel, A.

    2008-12-01

    Tropospheric ozone (O3) is formed in the presence of sunlight through the interaction of volatile organic compounds (VOCs) and NOX (NO, NO2). A photochemical equilibrium exists between NO, NO2 and O3; however in the presence of VOCs this equilibrium is broken and additional O3 is produced. O3 damages plants in several ways, most importantly by reducing net photosynthesis and growth. The extent of this damage depends on the time-integrated absorbed O3 flux (i.e. the dose), which is a function of leaf stomatal conductance and ambient O3 concentration, and further influenced by plant species specific defence mechanisms. VOCs are produced by plants through a variety of pathways and in response to large number of different driving forces. A large variety of VOCs are emitted by plants in response to stress conditions, including the foliar uptake of O3. Here we present preliminary data from an ongoing study where concurrent measurements of the fluxes of VOCs and O3 are made above a managed mountain grassland in Tyrol/Austria. Fluxes of several different VOCs are measured by means of the eddy covariance method and a proton transfer reaction mass spectrometer (PTR-MS). Fluxes of O3 are measured by both the eddy covariance method and a modified Bowen-ratio approach. The data analysis will try to identify whether VOC emissions change with the time-integrated uptake of O3 by plants.

  18. VOCs and OVOCs distribution and control policy implications in Pearl River Delta region, China

    NASA Astrophysics Data System (ADS)

    Louie, Peter K. K.; Ho, Josephine W. K.; Tsang, Roy C. W.; Blake, Donald R.; Lau, Alexis K. H.; Yu, Jian Zhen; Yuan, Zibing; Wang, Xinming; Shao, Min; Zhong, Liuju

    2013-09-01

    Ambient air measurements of volatile organic compounds (VOCs) and oxygenated volatile organic compounds (OVOCs) were conducted and characterised during a two-year grid study in the Pearl River Delta (PRD) region of southern China. The present grid study pioneered the systematic investigation of the nature and characteristics of complex VOC and OVOC sources at a regional scale. The largest contributing VOCs, accounting over 80% of the total VOCs mixing ratio, were toluene, ethane, ethyne, propane, ethene, butane, benzene, pentane, ethylbenzene, and xylenes. Sub-regional VOC spatial characteristics were identified, namely: i) relatively fresh pollutants, consistent with elevated vehicular and industrial activities, around the PRD estuary; and ii) a concentration gradient with higher mixing ratios of VOCs in the west as compared with the eastern part of PRD. Based on alkyl nitrate aging determination, a high hydroxyl radical (OH) concentration favoured fast hydrocarbon reactions and formation of locally produced ozone. The photochemical reactivity analysis showed aromatic hydrocarbons and alkenes together consisted of around 80% of the ozone formation potential (OFP) among the key VOCs. We also found that the OFP from OVOCs should not be neglected since their OFP contribution was more than one-third of that from VOCs alone. These findings support the choice of current air pollution control policy which focuses on vehicular sources but warrants further controls. Industrial emissions and VOCs emitted by solvents should be the next targets for ground-level ozone abatement.

  19. Emission of volatile organic compounds from silage: compounds, sources, and implications

    USDA-ARS?s Scientific Manuscript database

    Silage, fermented cattle feed, has recently been identified as a significant source of volatile organic compounds (VOCs) emitted to the atmosphere. A small number of studies have measured VOC emission from silage, but not enough is known about the processes involved to accurately quantify emission r...

  20. Ambient levels and temporal trends of VOCs, including carbonyl compounds, and ozone at Cabañeros National Park border, Spain

    NASA Astrophysics Data System (ADS)

    Villanueva, Florentina; Tapia, Araceli; Notario, Alberto; Albaladejo, José; Martínez, Ernesto

    2014-03-01

    Concentration levels of 15 carbonyls, 17 VOCs and ozone were studied at Cabañeros National Park border, Spain, in an area mainly constituted by holm oaks (Quercus ilex) and cork oaks (Quercus suber), along with scrubland formations such as rock-rose and heather. The compounds were collected by means of diffusive samplers from August-November 2010 and February-August 2011. Carbonyl compounds, VOCs and O3 were analysed by HPLC with diode array UV-Vis detector, GC-FID and by UV-visible spectrophotometry, respectively. The most abundant carbonyls were hexanal, acetone-acrolein, formaldehyde and acetaldehyde. Seasonal variation was apparent with maximum values observed in summer months. Total carbonyl concentrations ranged from 2.8 to 19.7 μg m-3. Most VOCs studied (using chemically desorbable cartridges) were either not detected or were below their detection limits, however, a parallel sampling using thermally desorbable cartridges, from May 22 to June 19, revealed the presence of much more VOCs, identified using GC-MS. O3 concentration ranged from 27.2 to 90.5 μg m-3, reaching the maximum monthly mean concentration in March (84.4 μg m-3). The analysis of back trajectories indicates the transport of polluted air masses from remote areas, mainly from the Mediterranean basin that should contribute to the high levels of ozone observed.

  1. Volatilization of low vapor pressure--volatile organic compounds (LVP-VOCs) during three cleaning products-associated activities: Potential contributions to ozone formation.

    PubMed

    Shin, Hyeong-Moo; McKone, Thomas E; Bennett, Deborah H

    2016-06-01

    There have been many studies to reduce ozone formation mostly from volatile organic compound (VOC) sources. However, the role of low vapor pressure (LVP)-VOCs from consumer products remains mostly unexplored and unaddressed. This study explores the impact of high production volume LVP-VOCs on ozone formation from three cleaning products-associated activities (dishwashing, clothes washing, and surface cleaning). We develop a model framework to account for the portion available for ozone formation during the use phase and from the down-the-drain disposal. We apply experimental studies that measured emission rates or models that were developed for estimating emission rates of organic compounds during the use phase. Then, the fraction volatilized (fvolatilized) and the fraction disposed down the drain (fdown-the-drain) are multiplied by the portion available for ozone formation for releases to the outdoor air (fO3|volatilized) and down-the-drain (fO3|down-the-drain), respectively. Overall, for chemicals used in three specific cleaning-product uses, fvolatilized is less than 0.6% for all studied LVP-VOCs. Because greater than 99.4% of compounds are disposed of down the drain during the use phase, when combined with fO3|volatilized and fO3|down-the-drain, the portion available for ozone formation from the direct releases to outdoor air and the down-the-drain disposal is less than 0.4% and 0.2%, respectively. The results from this study indicate that the impact of the studied LVP-VOCs on ozone formation is very sensitive to what occurs during the use phase and suggest the need for future research on experimental work at the point of use.

  2. A shape tailored gold-conductive polymer nanocomposite as a transparent electrode with extraordinary insensitivity to volatile organic compounds (VOCs)

    NASA Astrophysics Data System (ADS)

    Khalil, Rania; Homaeigohar, Shahin; Häußler, Dietrich; Elbahri, Mady

    2016-09-01

    In this study, the transparent conducting polymer of poly (3,4-ethylenendioxythiophene): poly(styrene sulphonate) (PEDOT:PSS) was nanohybridized via inclusion of gold nanofillers including nanospheres (NSs) and nanorods (NRs). Such nanocomposite thin films offer not only more optimum conductivity than the pristine polymer but also excellent resistivity against volatile organic compounds (VOCs). Interestingly, such amazing properties are achieved in the diluted regimes of the nanofillers and depend on the characteristics of the interfacial region of the polymer and nanofillers, i.e. the aspect ratio of the latter component. Accordingly, a shape dependent response is made that is more desirable in case of using the Au nanorods with a much larger aspect ratio than their nanosphere counterparts. This transparent nanocomposite thin film with an optimized conductivity and very low sensitivity to organic gases is undoubtedly a promising candidate material for the touch screen panel production industry. Considering PEDOT as a known material for integrated electrodes in energy saving applications, we believe that our strategy might be an important progress in the field.

  3. A shape tailored gold-conductive polymer nanocomposite as a transparent electrode with extraordinary insensitivity to volatile organic compounds (VOCs)

    PubMed Central

    Khalil, Rania; Homaeigohar, Shahin; Häußler, Dietrich; Elbahri, Mady

    2016-01-01

    In this study, the transparent conducting polymer of poly (3,4-ethylenendioxythiophene): poly(styrene sulphonate) (PEDOT:PSS) was nanohybridized via inclusion of gold nanofillers including nanospheres (NSs) and nanorods (NRs). Such nanocomposite thin films offer not only more optimum conductivity than the pristine polymer but also excellent resistivity against volatile organic compounds (VOCs). Interestingly, such amazing properties are achieved in the diluted regimes of the nanofillers and depend on the characteristics of the interfacial region of the polymer and nanofillers, i.e. the aspect ratio of the latter component. Accordingly, a shape dependent response is made that is more desirable in case of using the Au nanorods with a much larger aspect ratio than their nanosphere counterparts. This transparent nanocomposite thin film with an optimized conductivity and very low sensitivity to organic gases is undoubtedly a promising candidate material for the touch screen panel production industry. Considering PEDOT as a known material for integrated electrodes in energy saving applications, we believe that our strategy might be an important progress in the field. PMID:27654345

  4. Effect of traffic restriction on reducing ambient volatile organic compounds (VOCs): Observation-based evaluation during a traffic restriction drill in Guangzhou, China

    NASA Astrophysics Data System (ADS)

    Huang, Xinyu; Zhang, Yanli; Yang, Weiqiang; Huang, Zuzhao; Wang, Yujun; Zhang, Zhou; He, Quanfu; Lü, Sujun; Huang, Zhonghui; Bi, Xinhui; Wang, Xinming

    2017-07-01

    Traffic restriction (TR) is a widely adopted control measure in case of heavy air pollution particularly in urban areas, yet it is hard to evaluate the effect of TR on reducing VOC emissions based on monitoring data since ambient VOC mixing ratios are influenced not only by source emissions but also by meteorological conditions and atmospheric degradation. Here we collected air samples for analysis of VOCs before, during and after a TR drill carried out in Guangzhou in September 2010 at both a roadside and a rooftop (∼50 m above the ground) site. TR measures mainly included the ;odd-even license; rule and banning high-emitting ;yellow label; vehicles. The mixing ratios of non-methane hydrocarbons (NMHCs) did not show significant changes at the roadside site with total NMHCs of 39.0 ± 11.8 ppbv during non-TR period and 39.1 ± 14.8 ppbv during TR period, whereas total NMHCs decreased from 30.4 ± 14.3 ppbv during the non-TR period to 22.1 ± 10.6 ppbv during the TR period at rooftop site. However, the ratios of methyl tert-butyl ether (MTBE), benzene and toluene against carbon monoxide (MTBE/CO, T/CO and B/CO) at the both sampling sites dropped significantly. The ratios of toluene to benzene (T/B) instead increased significantly. Changes in these ratios all consistently indicated reduced input from traffic emissions particularly gasoline vehicles. Source attribution by positive matrix factorization (PMF) confirmed that during the TR period gasoline vehicles contributed less VOCs in percentages while industrial sources, biomass burning and LPG shared larger percentages. Assuming that emissions from industrial sources remained unchanged during the TR and non-TR periods, we further used the PMF-retrieved contribution percentages to deduce the reduction rate of traffic-related VOC emissions, and obtained a reduction rate of 31% based on monitoring data at the roadside site and of 34% based on the monitoring data at the rooftop site. Considering VOC emissions from all

  5. mVOC: a database of microbial volatiles

    PubMed Central

    Lemfack, Marie Chantal; Nickel, Janette; Dunkel, Mathias; Preissner, Robert; Piechulla, Birgit

    2014-01-01

    Scents are well known to be emitted from flowers and animals. In nature, these volatiles are responsible for inter- and intra-organismic communication, e.g. attraction and defence. Consequently, they influence and improve the establishment of organisms and populations in ecological niches by acting as single compounds or in mixtures. Despite the known wealth of volatile organic compounds (VOCs) from species of the plant and animal kingdom, in the past, less attention has been focused on volatiles of microorganisms. Although fast and affordable sequencing methods facilitate the detection of microbial diseases, however, the analysis of signature or fingerprint volatiles will be faster and easier. Microbial VOCs (mVOCs) are presently used as marker to detect human diseases, food spoilage or moulds in houses. Furthermore, mVOCs exhibited antagonistic potential against pathogens in vitro, but their biological roles in the ecosystems remain to be investigated. Information on volatile emission from bacteria and fungi is presently scattered in the literature, and no public and up-to-date collection on mVOCs is available. To address this need, we have developed mVOC, a database available online at http://bioinformatics.charite.de/mvoc. PMID:24311565

  6. Leaf ontogeny dominates the seasonal exchange of volatile organic compounds (VOC) in a SRC-poplar plantation during an entire growing season

    NASA Astrophysics Data System (ADS)

    Brilli, Federico; Gioli, Beniamino; Fares, Silvano; Zenone, Terenzio; Zona, Donatella; Gielen, Bert; Loreto, Francesco; Janssens, Ivan; Ceulemans, Reinhart

    2015-04-01

    The declining cost of many renewable energy technologies and changes in the prices of fossil fuels have recently encouraged governments policies to subsidize the use of biomass as a sustainable source of energy. Deciduous poplars (Populus spp.) trees are often selected for biomass production in short rotation coppiced (SRC) for their high CO2 photosynthetic assimilation rates and their capacity to develop dense canopies with high values of leaf area index (LAI). So far, observations and projections of seasonal variations of many VOC fluxes has been limited to strong isoprenoids emitting evergreen ecosystems such tropical and Mediterranean forests as well as Citrus and oil palm plantation, all having constant values of LAI. We run a long-term field campaign where the exchange of VOC, together with CO2 and water vapor was monitored during an entire growing season (June - November, 2012) above a SRC-based poplar plantation. Our results confirmed that isoprene and methanol were the most abundant fluxes emitted, accounting for more than 90% of the total carbon released in form of VOC. However, Northern climates characterized by fresh summertime temperatures and recurring precipitations favored poplar growth while inhibiting the development of isoprene emission that resulted in only 0.7% of the net ecosystem carbon exchange (NEE). Besides, measurements of a multitude of VOC fluxes by PTR-TOF-MS showed bi-directional exchange of oxygenated-VOC (OVOC) such as: formaldehyde, acetaldehyde, acetone, isoprene oxidation products (iox, namely MVK, MAC and MEK) as well as ethanol and formic acid. The application of Self Organizing Maps to visualize the relationship between the full time-series of many VOC fluxes and the observed seasonal variations of environmental, physiological and structural parameters proved the most abundant isoprene ad methanol fluxes to occur mainly on the hottest days under mid-high light intensities when also NEE and evapotraspiration reached the highest

  7. Characterization of trace gases measured over Alberta oil sands mining operations: 76 speciated C2-C10 volatile organic compounds (VOCs), CO2, CH4, CO, NO, NO2, NOy, O3 and SO2

    NASA Astrophysics Data System (ADS)

    Simpson, I. J.; Blake, N. J.; Barletta, B.; Diskin, G. S.; Fuelberg, H. E.; Gorham, K.; Huey, L. G.; Meinardi, S.; Rowland, F. S.; Vay, S. A.; Weinheimer, A. J.; Yang, M.; Blake, D. R.

    2010-08-01

    Oil sands comprise 30% of the world's oil reserves and the crude oil reserves in Canada's oil sands deposits are second only to Saudi Arabia. The extraction and processing of oil sands is much more challenging than for light sweet crude oils because of the high viscosity of the bitumen contained within the oil sands and because the bitumen is mixed with sand and contains chemical impurities such as sulphur. Despite these challenges, the importance of oil sands is increasing in the energy market. To our best knowledge this is the first peer-reviewed study to characterize volatile organic compounds (VOCs) emitted from Alberta's oil sands mining sites. We present high-precision gas chromatography measurements of 76 speciated C2-C10 VOCs (alkanes, alkenes, alkynes, cycloalkanes, aromatics, monoterpenes, oxygenates, halocarbons, and sulphur compounds) in 17 boundary layer air samples collected over surface mining operations in northeast Alberta on 10 July 2008, using the NASA DC-8 airborne laboratory as a research platform. In addition to the VOCs, we present simultaneous measurements of CO2, CH4, CO, NO, NO2, NOy, O3 and SO2, which were measured in situ aboard the DC-8. Methane, CO, CO2, NO, NO2, NOy, SO2 and 53 VOCs (e.g., halocarbons, sulphur species, NMHCs) showed clear statistical enhancements (up to 1.1-397×) over the oil sands compared to local background values and, with the exception of CO, were higher over the oil sands than at any other time during the flight. Twenty halocarbons (e.g., CFCs, HFCs, halons, brominated species) either were not enhanced or were minimally enhanced (< 10%) over the oil sands. Ozone levels remained low because of titration by NO, and three VOCs (propyne, furan, MTBE) remained below their 3 pptv detection limit throughout the flight. Based on their mutual correlations, the compounds emitted by the oil sands industry fell into two groups: (1) evaporative emissions from the oil sands and its products and/or from the diluent used to

  8. 40 CFR Table 1 to Subpart D of... - Volatile Organic Compound (VOC), Content Limits for Architectural Coatings

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...), Content Limits for Architectural Coatings Coating category Grams VOC per liter Pounds VOC per gallon a... interior clear wood sealers) 400 3.3 Shellacs: Clear 730 6.1 Opaque 550 4.6 Stains: Clear and semitransparent 550 4.6 Opaque 350 2.9 Low solids b 120 b 1.0 Stain controllers 720 6.0 Swimming pool coatings...

  9. 40 CFR Table 1 to Subpart D of... - Volatile Organic Compound (VOC), Content Limits for Architectural Coatings

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...), Content Limits for Architectural Coatings Coating category Grams VOC per liter Pounds VOC per gallon a... interior clear wood sealers) 400 3.3 Shellacs: Clear 730 6.1 Opaque 550 4.6 Stains: Clear and semitransparent 550 4.6 Opaque 350 2.9 Low solids b 120 b 1.0 Stain controllers 720 6.0 Swimming pool coatings...

  10. 40 CFR Table 1 to Subpart D of... - Volatile Organic Compound (VOC), Content Limits for Architectural Coatings

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...), Content Limits for Architectural Coatings Coating category Grams VOC per liter Pounds VOC per gallon a... interior clear wood sealers) 400 3.3 Shellacs: Clear 730 6.1 Opaque 550 4.6 Stains: Clear and semitransparent 550 4.6 Opaque 350 2.9 Low solids b 120 b 1.0 Stain controllers 720 6.0 Swimming pool coatings...

  11. 40 CFR Table 1 to Subpart D of... - Volatile Organic Compound (VOC), Content Limits for Architectural Coatings

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...), Content Limits for Architectural Coatings Coating category Grams VOC per liter Pounds VOC per gallon a... interior clear wood sealers) 400 3.3 Shellacs: Clear 730 6.1 Opaque 550 4.6 Stains: Clear and semitransparent 550 4.6 Opaque 350 2.9 Low solids b 120 b 1.0 Stain controllers 720 6.0 Swimming pool coatings...

  12. 40 CFR Table 1 to Subpart D of... - Volatile Organic Compound (VOC), Content Limits for Architectural Coatings

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...), Content Limits for Architectural Coatings Coating category Grams VOC per liter Pounds VOC per gallon a... interior clear wood sealers) 400 3.3 Shellacs: Clear 730 6.1 Opaque 550 4.6 Stains: Clear and semitransparent 550 4.6 Opaque 350 2.9 Low solids b 120 b 1.0 Stain controllers 720 6.0 Swimming pool coatings...

  13. Control of industrial VOC (volatile organic compound) emissions by catalytic incineration. volume 5. catalytic incinerator performance at industrial site c-3. Final report, May 1982-August 1983

    SciTech Connect

    Blacksmith, J.R.; Randall, J.L.

    1984-07-01

    The report is part of a two-phase EPA effort to assess the performance, suitability, and costs of various technologies to control emissions of volatile organic compounds (VOCs). In Phase 1, information was assembled from the literature on the use and cost of using catalytic incineration for VOC control. Results included: (1) a review of current and developing catalytic incineration technology, (2) an assessment of the overall performance of catalytic incinerators, (3) a review of applications where catalytic incinerators are used, (4) a comparative analysis of catalytic incineration with other competing VOC controls, (5) an examination of available methods for emission testing catalytic incinerators, and (6) an assessment of the need for additional performance test data. Phase 2 was a test program designed to increase the catalytic incinerator performance data base. It resulted in reports documenting the performance of eight catalytic incinerators at six industrial sites. The incinerators were used to control VOC emissions from solvent evaporation processes at can coating, coil coating, magnet wire, and graphic arts printing plants. Performance was measured at several process conditions at each site. Incinerator performance was characterized in terms of destruction efficiency, outlet solvent concentration, and energy usage. Design and operating data were collected. This report preseents test resultls and data evaluation for the testing conducted at the third test site, which involved the testing of two catalytic incinerators at Plant C-3, a graphic arts printing establishment.

  14. Natural attenuation of volatile organic compounds (VOCs) in the leachate plume of a municipal landfill: Using alkylbenzenes as process probes

    USGS Publications Warehouse

    Eganhouse, R.P.; Cozzarelli, I.M.; Scholl, M.A.; Matthews, L.L.

    2001-01-01

    More than 70 individual VOCs were identified in the leachate plume of a closed municipal landfill. Concentrations were low when compared with data published for other landfills, and total VOCs accounted for less than 0.1% of the total dissolved organic carbon. The VOC concentrations in the core of the anoxic leachate plume are variable, but in all cases they were found to be near or below detection limits within 200 m of the landfall. In contrast to the VOCs, the distributions of chloride ion, a conservative tracer, and nonvolatile dissolved organic carbon, indicate little dilution over the same distance. Thus, natural attentuation processes are effectively limiting migration of the VOC plume. The distribution of C2-3-benzenes, paired on the basis of their octanol-water partition coefficients and Henry's law constants, were systematically evaluated to assess the relative importance of volatilization, sorption, and biodegradation as attenuation mechanisms. Based on our data, biodegradation appears to be the process primarily responsible for the observed attenuation of VOCs at this site. We believe that the alkylbenzenes are powerful process probes that can and should be exploited in studies of natural attenuation in contaminated ground water systems.

  15. Emissions of volatile organic compounds during the decomposition of plant litter

    NASA Astrophysics Data System (ADS)

    Gray, Christopher M.; Monson, Russell K.; Fierer, Noah

    2010-09-01

    Volatile organic compounds (VOCs) are emitted during plant litter decomposition, and such VOCs can have wide-ranging impacts on atmospheric chemistry, terrestrial biogeochemistry, and soil ecology. However, we currently have a limited understanding of the relative importance of biotic versus abiotic sources of these VOCs and whether distinct types of litter emit different types and quantities of VOCs during decomposition. We analyzed VOCs emitted by microbes or by abiotic mechanisms during the decomposition of litter from 12 plant species in a laboratory experiment using proton transfer reaction mass spectrometry (PTR-MS). Net emissions from litter with active microbial populations (non-sterile litters) were between 0 and 11 times higher than emissions from sterile controls over a 20-d incubation period, suggesting that abiotic sources of VOCs are generally less important than biotic sources. In all cases, the sterile and non-sterile litter treatments emitted different types of VOCs, with methanol being the dominant VOC emitted from litters during microbial decomposition, accounting for 78 to 99% of the net emissions. We also found that the types of VOCs released during biotic decomposition differed in a predictable manner among litter types with VOC profiles also changing as decomposition progressed over time. These results show the importance of incorporating both the biotic decomposition of litter and the species-dependent differences in terrestrial vegetation into global VOC emission models.

  16. Quantifying VOC emissions for the strategic petroleum reserve.

    SciTech Connect

    Knowlton, Robert G.; Lord, David L.

    2013-06-01

    A very important aspect of the Department of Energys (DOEs) Strategic Petroleum Reserve (SPR) program is regulatory compliance. One of the regulatory compliance issues deals with limiting the amount of volatile organic compounds (VOCs) that are emitted into the atmosphere from brine wastes when they are discharged to brine holding ponds. The US Environmental Protection Agency (USEPA) has set limits on the amount of VOCs that can be discharged to the atmosphere. Several attempts have been made to quantify the VOC emissions associated with the brine ponds going back to the late 1970s. There are potential issues associated with each of these quantification efforts. Two efforts were made to quantify VOC emissions by analyzing VOC content of brine samples obtained from wells. Efforts to measure air concentrations were mentioned in historical reports but no data have been located to confirm these assertions. A modeling effort was also performed to quantify the VOC emissions. More recently in 2011- 2013, additional brine sampling has been performed to update the VOC emissions estimate. An analysis of the statistical confidence in these results is presented here. Arguably, there are uncertainties associated with each of these efforts. The analysis herein indicates that the upper confidence limit in VOC emissions based on recent brine sampling is very close to the 0.42 ton/MMB limit used historically on the project. Refining this estimate would require considerable investment in additional sampling, analysis, and monitoring. An analysis of the VOC emissions at each site suggests that additional discharges could be made and stay within current regulatory limits.

  17. Comparisons of diffusive and advective fluxes of gas phase volatile organic compounds (VOCs) in unsaturated zones under natural conditions

    NASA Astrophysics Data System (ADS)

    You, Kehua; Zhan, Hongbin

    2013-02-01

    Diffusive flux is traditionally treated as the dominant mechanism of gas transport in unsaturated zones under natural conditions, and advective flux is usually neglected. However, some researchers have found that pressure-driven and density-driven advective flux may also be significant under certain conditions. This article compares the diffusive, pressure-driven and density-driven advective fluxes of gas phase volatile organic compound (VOCs) in unsaturated zones under various natural conditions. The presence of a less or more permeable layer at ground surface in a layered unsaturated zone is investigated for its impact on the net contribution of advective and diffusive fluxes. Results show although the transient advective flux can be greater than the diffusive flux, under most of the field conditions the net contribution of the advective flux is one to three orders of magnitude less than the diffusive flux, and the influence of the density-driven flux is undetectable. The advective flux contributes comparably with the diffusive flux only when the gas-filled porosity is less than 0.05. The presence of a less permeable layer at ground surface slightly increases the total flux in the underlying layer, while the presence of a more permeable layer at ground surface significantly increases the total flux in it. When the magnitude of water table fluctuation is less than 1 cm, and the period is greater than 0.5 day, the fluctuation of the water table can be simulated by fixing the water table position and setting a fluctuating moving velocity at the water table.

  18. Characterization of gaseous and semi-volatile organic compounds emitted from field burning of rice straw

    NASA Astrophysics Data System (ADS)

    Kim Oanh, Nguyen Thi; Tipayarom, Aungsiri; Bich, Thuy Ly; Tipayarom, Danutawat; Simpson, Christopher D.; Hardie, David; Sally Liu, L.-J.

    2015-10-01

    Rice straw (RS) field burning, commonly practiced in Asia, produces large amounts of toxic air pollutants but has not been comprehensively characterized. This study conducted field and laboratory measurements for gaseous pollutants and semi-VOCs (16 PAHs, 16 chlorinated pesticides and 14 PCBs) in RS burning smoke to determine emission factors (EFs) and emission concentration profiles. Paddy burning experiments were done following common practices used by farmers in Southeast Asia and EFs were estimated using the carbon balance method. Laboratory hood experiments simulated burning of dry RS (moisture content ∼ 5%) and normal RS (moisture ∼ 23-30%). Semi-VOCs were analyzed separately in the particulate (PM) and gas phases, and the levels measured in smoke were compared with those in the paddy background and in general ambient air to identify enrichment of the compounds. Lower EFs of all pollutants were obtained for hood burning dry RS as compared to hood burning normal RS. EFs of all detected pollutants in the field burning were higher than hood burning. The EFs of field burning in mg kg-1 RS were 760 for benzene, 230 for toluene, 510 for SO2, 490 for NO2, 260 for total PAHs (88% in gas phase), 0.11 for total PCBs (59% in gas phase) and 0.23 for OCPs (62% in gas phase). The EF of aldehydes determined in the hood experiment was 80-150 mg kg-1 RS. As compared to ambient air, RS smoke had significant enrichment of light PAHs, fluoranthene in PM and acenaphthylene in gas phase. Smoke had a higher proportion of benzene in BTEX than roadside air. Levels of PCBs, OCPs and aldehydes were higher in the burning smoke compared to ambient air, but there was no significant enrichment of particular compounds. This study provides appropriate ranges of EFs for developing emission inventory of RS spread field burning.

  19. Anthropogenic and biogenic influence on VOC fluxes at an urban background site in Helsinki, Finland

    NASA Astrophysics Data System (ADS)

    Rantala, Pekka; Järvi, Leena; Taipale, Risto; Laurila, Terhi K.; Patokoski, Johanna; Kajos, Maija K.; Kurppa, Mona; Haapanala, Sami; Siivola, Erkki; Petäjä, Tuukka; Ruuskanen, Taina M.; Rinne, Janne

    2016-07-01

    We measured volatile organic compounds (VOCs), carbon dioxide (CO2) and carbon monoxide (CO) at an urban background site near the city centre of Helsinki, Finland, northern Europe. The VOC and CO2 measurements were obtained between January 2013 and September 2014 whereas for CO a shorter measurement campaign in April-May 2014 was conducted. Both anthropogenic and biogenic sources were identified for VOCs in the study. Strong correlations between VOC fluxes and CO fluxes and traffic rates indicated anthropogenic source of many VOCs. The VOC with the highest emission rate to the atmosphere was methanol, which originated mostly from traffic and other anthropogenic sources. The traffic was also a major source for aromatic compounds in all seasons whereas isoprene was mostly emitted from biogenic sources during summer. Some amount of traffic-related isoprene emissions were detected during other seasons but this might have also been an instrumental contamination from cycloalkane products. Generally, the observed VOC fluxes were found to be small in comparison with previous urban VOC flux studies. However, the differences were probably caused by lower anthropogenic activities as the CO2 fluxes were also relatively small at the site.

  20. Analysis and quantitation of volatile organic compounds emitted from plastics used in museum construction by evolved gas analysis-gas chromatography-mass spectrometry.

    PubMed

    Samide, Michael J; Smith, Gregory D

    2015-12-24

    Construction materials used in museums for the display, storage, and transportation of artwork must be assessed for their tendency to emit harmful pollution that could potentially damage cultural treasures. Traditionally, a subjective metals corrosion test known as the Oddy test has been widely utilized in museums for this purpose. To augment the Oddy test, an instrumental sampling approach based on evolved gas analysis (EGA) coupled to gas chromatography (GC) with mass spectral (MS) detection has been implemented for the first time to qualitatively identify off-gassed pollutants under specific conditions. This approach is compared to other instrumental methods reported in the literature. This novel application of the EGA sampling technique yields several benefits over traditional testing, including rapidity, high sensitivity, and broad detectability of volatile organic compounds (VOCs). Furthermore, unlike other reported instrumental approaches, the EGA method was used to determine quantitatively the amount of VOCs emitted by acetate resins and polyurethane foams under specific conditions using both an external calibration method as well as surrogate response factors. EGA was successfully employed to rapidly characterize emissions from 12 types of common plastics. This analysis is advocated as a rapid pre-screening method to rule out poorly performing materials prior to investing time and energy in Oddy testing. The approach is also useful for rapid, routine testing of construction materials previously vetted by traditional testing, but which may experience detrimental formulation changes over time. As an example, a case study on batch re-orders of rigid expanded poly(vinyl chloride) board stock is presented. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Volatile Organic Compounds (VOCs)

    MedlinePlus

    ... provides general solutions for resolving the syndrome. Indoor Air Pollution: An Introduction for Health Professionals Assists health professionals ( ... symptoms that could be related to an indoor air pollution problem. Addresses the health problems that may be ...

  2. Ambient air levels of volatile organic compounds (VOC) and nitrogen dioxide (NO2) in a medium size city in Northern Spain.

    PubMed

    Parra, M A; Elustondo, D; Bermejo, R; Santamaría, J M

    2009-01-15

    Ambient concentrations of volatile organic compounds (VOC) and nitrogen dioxide (NO2) were measured by means of passive sampling at 40 sampling points in a medium-size city in Northern Spain, from June 2006 to June 2007. VOC and NO2 samplers were analysed by thermal desorption followed by gas chromatography/mass-selective detector and by visible spectrophotometry, respectively. Mean concentrations of benzene, toluene, ethylbenzene, xylenes, propylbenzene, trimethylbenzenes, and NO(2) were 2.84, 13.26, 2.15, 6.01, 0.59, 1.32 and 23.17 microg m(-3) respectively, and found to be highly correlated. Their spatial distribution showed high differences in small distances and pointed to traffic as the main emission source of these compounds. The lowest levels of VOC and NO2 occurred during summer, owing to the increase in solar radiation and to lower traffic densities. Mean concentrations of benzene and NO2 exceeded the European limits at some of the monitored points.

  3. Putting VOC Measurements During SOAS 2013 in Context of Historical Observations: How Have VOC Emissions in the Alabama Region Changed Since the SOS 1990 Study?

    NASA Astrophysics Data System (ADS)

    Olson, K. F.; Koss, A.; De Gouw, J. A.; Goldstein, A. H.

    2013-12-01

    Volatile organic compounds (VOCs) play an important role in atmospheric photochemistry. They react with atmospheric oxidants to form ozone and secondary organic aerosols (SOA). VOCs are emitted from a variety of anthropogenic and biogenic sources. The Southeastern United States (SEUS) is heavily forested with high biogenic VOCs emissions. There are many anthropogenic air pollution sources in the region, including urban centers and power plants. This makes the SEUS an ideal location to study the chemistry of biogenic VOCs in the presence of anthropogenic emissions. The SEUS has hosted several large atmospheric chemistry field campaigns. The Southern Oxidant and Aerosol Study (SOAS) took place in a forested site near Centerville, AL from June 1st to July 15th, 2013. SOAS included a comprehensive suite of instruments measuring VOCs, oxidants, aerosol properties and meteorology. During the campaign, in-situ gas chromatography - mass spectrometry (GC-MS) was used to measure VOCs at the SOAS Centreville ground site. We put these VOC measurements in perspective of measurements from previous campaigns in the SEUS including the Southern Oxidant Study (SOS) campaign in the 1990s as well as measurements during June and July 1990 in a loblolly pine plantation in western Alabama as part of the Rural Oxidants in the Southern Environment program. We analyze how VOC levels vary within the region and how regional photochemistry has changed in recent decades.

  4. Experiments in the EMRP project KEY-VOCs: Adsorption/desorption effects of VOCs in different tubing materials and preparation and analysis of a zero gas

    NASA Astrophysics Data System (ADS)

    Englert, Jennifer; Claude, Anja; Kubistin, Dagmar; Tensing, Erasmus; Michl, Katja; Plass-Duelmer, Christian

    2017-04-01

    Atmospheric chemistry and composition are influenced by volatile organic compounds (VOCs) emitted from natural and anthropogenic sources. Due to their toxicity and their crucial role in ozone and aerosol formation VOCs impact air quality and climate change and high quality observations are demanded. The European Metrology Research Programme (EMRP) project KEY-VOCs has targeted the improvement of VOC measurement capabilities with the focus on VOCs relevant for indoor air as well as for air quality and climate monitoring programmes. One major uncertainty is the influence of surface effects of the measurement devices. By developing a test system the adsorption/desorption effects of certain VOCs can be systematically examined. Different tubing materials e.g. stainless steel and PFA were analysed with the oxygenated VOC methanol and results of these experiments will be presented. In air quality monitoring very low levels of VOCs have to be measured. Purified air or nitrogen is widely used as a zero gas to characterize measurement systems and procedures as well as for instrument calibration. A high quality zero gas is an important contributor to the quality of the measurements and generally achieved by using state-of-the-art purification technologies. The efficiency of several air purifiers was assessed and the results have been analysed.

  5. Profiling of soil volatile organic compounds after long-term application of inorganic, organic and organic-inorganic mixed fertilizers and their effect on plant growth.

    PubMed

    Raza, Waseem; Mei, Xinlan; Wei, Zhong; Ling, Ning; Yuan, Jun; Wang, Jichen; Huang, Qiwei; Shen, Qirong

    2017-12-31

    The complexity of soil processes involved in the production, consumption and accumulation of volatile organic compounds (VOCs) makes hard to access the overall dynamics of VOCs in the soil. In this study, the field soil, applied with inorganic (CF), organic (OF) and inorganic-organic mixed (CFOF) fertilizers for ten years was evaluated for the emission of VOCs at different temperature and moisture levels. We identified 30-50 soil emitted VOCs representing the most common soil VOCs groups by using the solid-phase microextraction (SPME) fiber and gas chromatography-mass spectroscopy. The highest total emission of VOCs was found in OF treatment, but it was non-significantly different with CF treatment. The emission of VOCs was significantly increased with the decrease in moisture contents and increase in the temperature of the soil. Among different fertilizer treatments, the emission of VOCs was significantly higher in OF treatment at 5% moisture, and in CF and OF treatments at 35°C. Further, the VOCs emitted from soil treated with CFOF showed the highest increase in plant growth while CF and OF treatments showed similar results. The VOCs were also extracted from the soil using methanol to better understand the dynamics of VOCs. The abundance of VOCs extracted from the soil was 44-61%, while the richness was 65-70% higher than the VOCs emitted from the soil in different treatments. Taken together the results of emitted and extracted VOCs from the soil, we conclude that the fertilizers are able to discriminate among the VOC patterns of soil. In addition, most of the VOCs are retained in the soil and the emission of VOCs from soil depends on the type of VOCs, soil properties and environmental conditions; however, more research is required to find out better soil VOCs analysis methods. Copyright © 2017. Published by Elsevier B.V.

  6. New method to quantify volatile organic compounds (VOCs) in cloud droplets sampled at the puy de Dôme research station.

    NASA Astrophysics Data System (ADS)

    Colomb, A.; Fleuret, J.; Gaimoz, C.; Deguillaume, L.

    2012-04-01

    In recent years several studies have focused on the health and environmental effects of atmospheric pollution, and especially on the emissions of volatile organic compounds (VOCs). In cloud droplets, chemical reactions in the liquid phase modify the amount of radicals which drive the oxidizing power of the atmosphere. The objective of this project was to identify and quantify VOCs in cloud water samples at the puy de Dôme research site using a combination of stir bar sorptive extraction (SBSE)-thermal desorption (TD)-gas chromatography-mass spectrometry (GC-MS). Experimental studies were carried out at the puy de Dôme (PDD) Station (48°N, 2°E; 1465 m a.s.l.), in the Massif Central Region (France). It is a strategic point from which to observe warm and mixed clouds that are present 30% of the time on an annual basis. Clouds are frequently formed at the top of the site either during advection of frontal systems or by orographic rise of moist air. The station is in the free troposphere a large fraction of the time and air masses are usually exempt from the influence of local pollution. Non-precipitating cloud droplets are sampled using a single-stage cloud collector. Cloud droplets larger than 7 µm (cut-off diameter) are collected by impaction onto a rectangular plate at a flow rate of approximately 86 m3 h-1. This work has established a functional procedure to allow the quantitative extraction of 80 VOCs in cloud water. The method has been optimized to determine the best repeatability and detection limit for most of the compounds (hydrophobic and hydrophilic). According to SBSE theory, at equilibrium the distribution coefficients of the analytes between the aqueous matrix and coated film of the stir bar (PDMS) are correlated with the corresponding octanol-water partitioning coefficients (Kpdms/w vs Ko/w). Hydrophobic compounds, characterized by a high octanol-water distribution coefficient (Kow), are extracted from water by SBSE with a high recovery. However

  7. Biogenic volatile organic compounds (BVOC) emitted and accumulated by herbaceous and woody California crops

    NASA Astrophysics Data System (ADS)

    Ormeño, E.; Fares, S.; Park, J.; Gentner, D. R.; Karlik, J. F.; Goldstein, A. H.

    2009-12-01

    Emissions from vegetation may substantially influence regional air quality in California. However, the emission potentials of many important crop species have not been extensively studied, although they comprise extensive areas of landcover within this state. A better knowledge of the emission rate at the species-specific level is critical for reducing uncertainties in emission inventories and evaluating emission model performance. In the present study we identify and quantify BVOC produced (emitted and stored) by leaves of 22 dominant agricultural woody and herbaceous crops in California. Emissions were studied by means of a dynamic cuvette system where a whole plant (herbaceous species) or a branch (woody species) was enclosed. Emitted BVOC were collected by passing air from the cuvette enclosing the branch through a glass tube packed with carbon based adsorbents. The adsorbents were later liquid extracted and concentrated in the laboratory. BVOCs stored in the plant tissues were extracted with an organic solvent, after plant grinding. Both BVOC emitted and BVOC stored were identified and quantified using the same GC-MS equipment. Most identified leaf emissions and stored compounds were terpenoids, but BVOC from other biosynthetic classes (benzenoids and fatty acid derivates)were not negligible. The relationship between different BVOC classes and between emitted and stored terpenoids will be presented. Differences between herbaceous and woody crops, and a variety of foliar secretory structures (e.g. secretory cavities, secretory ducts, glandular trichomes, and glands), will be evaluated in terms of BVOC content and emissions to the atmosphere.

  8. Quantification of Methane and VOC Emissions from Natural Gas Production in Two Basins with High Ozone Events

    NASA Astrophysics Data System (ADS)

    Edie, R.; Robertson, A.; Snare, D.; Soltis, J.; Field, R. A.; Murphy, S. M.

    2015-12-01

    Since 2005, the Uintah Basin of Utah and the Upper Green River Basin of Wyoming frequently exceeded the EPA 8-hour allowable ozone level of 75 ppb, spurring interest in volatile organic compounds (VOCs) emitted during oil and gas production. Debate continues over which stage of production (drilling, flowback, normal production, transmission, etc.) is the most prevalent VOC source. In this study, we quantify emissions from normal production on well pads by using the EPA-developed Other Test Method 33a. This methodology combines ground-based measurements of fugitive emissions with 3-D wind data to calculate the methane and VOC emission fluxes from a point source. VOC fluxes are traditionally estimated by gathering a canister of air during a methane flux measurement. The methane:VOC ratio of this canister is determined at a later time in the laboratory, and applied to the known methane flux. The University of Wyoming Mobile Laboratory platform is equipped with a Picarro methane analyzer and an Ionicon Proton Transfer Reaction-Time of Flight-Mass Spectrometer, which provide real-time methane and VOC data for each well pad. This independent measurement of methane and VOCs in situ reveals multiple emission sources on one well pad, with varying methane:VOC ratios. Well pad emission estimates of methane, benzene, toluene and xylene for the two basins will be presented. The different emission source VOC profiles and the limitations of real-time and traditional VOC measurement methods will also be discussed.

  9. Diffuse emissions of Volatile Organic Compounds (VOCs) from soil in volcanic and hydrothermal systems: evidences for the influence of microbial activity on the carbon budget

    NASA Astrophysics Data System (ADS)

    Venturi, Stefania; Tassi, Franco; Fazi, Stefano; Vaselli, Orlando; Crognale, Simona; Rossetti, Simona; Cabassi, Jacopo; Capecchiacci, Francesco

    2017-04-01

    Soils in volcanic and hydrothermal areas are affected by anomalously high concentrations of gases released from the deep reservoirs, which consists of both inorganic (mainly CO2 and H2S) and organic (volatile organic compounds; VOCs) species. VOCs in volcanic and hydrothermal fluids are mainly composed of saturated and unsaturated hydrocarbons (alkanes, aromatics, alkenes, and cyclics), with variable concentrations of O- and S-bearing compounds and halocarbons, depending on the physicochemical conditions at depth. VOCs in interstitial soil gases and fumarolic emissions from four volcanic and hydrothermal systems in the Mediterranean area (Solfatara Crater, Poggio dell'Olivo and Cava dei Selci, in Italy, and Nisyros Island, in Greece) evidenced clear compositional differences, suggesting that their behavior is strongly affected by secondary processes occurring at shallow depths and likely controlled by microbial activity. Long-chain saturated hydrocarbons were significantly depleted in interstitial soil gases with respect to those from fumarolic discharges, whereas enrichments in O-bearing compounds (e.g. aldehydes, ketones), DMSO2 and cyclics were commonly observed. Benzene was recalcitrant to degradation processes, whereas methylated aromatics were relatively instable. The chemical and isotopic (δ13C in CO2 and CH4) composition of soil gases collected along vertical profiles down to 50 cm depth at both Solfatara Crater and Poggio dell'Olivo (Italy) showed evidences of relevant oxidation processes in the soil, confirming that microbial activity likely plays a major role in modifying the composition of deep-derived VOCs. Despite their harsh conditions, being typically characterized by high temperatures, low pH, and high toxic gases and metal contents, the variety of habitats characterizing volcanic and hydrothermal environments offers ideal biomes to extremophilic microbes, whose metabolic activity can consume and/or produce VOCs. In the Solfatara Crater, microbial

  10. Synthesis and Electroluminescent Property of New Orange Iridium Compounds for Flexible White Organic Light Emitting Diodes.

    PubMed

    Lee, Ho Won; Jeong, Hyunjin; Kim, Young Kwan; Ha, Yunkyoung

    2015-10-01

    Recently, white organic light-emitting diodes (OLEDs) have aroused considerable attention because they have the potential of next-generation flexible displays and white illuminated applications. White OLED applications are particularly heading to the industry but they have still many problems both materials and manufacturing. Therefore, we proposed that the new iridium compounds of orange emitters could be demonstrated and also applied to flexible white OLEDs for verification of potential. First, we demonstrated the chemical properties of new orange iridium compounds. Secondly, conventional two kinds of white phosphorescent OLEDs were fabricated by following devices; indium-tin oxide coated glass substrate/4,4'-bis[N-(napthyl)-N-phenylamino]biphenyl/N,N'-dicarbazolyl-3,5-benzene doped with blue and new iridium compounds for orange emitting 8 wt%/1,3,5-tris[N-phenylbenzimidazole-2-yl]benzene/lithium quinolate/aluminum. In addition, we fabricated white OLEDs using these emitters to verify the potential on flexible substrate. Therefore, this work could be proposed that white light applications can be applied and could be extended to additional research on flexible applications.

  11. Concentration, ozone formation potential and source analysis of volatile organic compounds (VOCs) in a thermal power station centralized area: A study in Shuozhou, China.

    PubMed

    Yan, Yulong; Peng, Lin; Li, Rumei; Li, Yinghui; Li, Lijuan; Bai, Huiling

    2017-04-01

    Volatile organic compounds (VOCs) from two sampling sites (HB and XB) in a power station centralized area, in Shuozhou city, China, were sampled by stainless steel canisters and measured by gas chromatography-mass selective detection/flame ionization detection (GC-MSD/FID) in the spring and autumn of 2014. The concentration of VOCs was higher in the autumn (HB, 96.87 μg/m(3); XB, 58.94 μg/m(3)) than in the spring (HB, 41.49 μg/m(3); XB, 43.46 μg/m(3)), as lower wind speed in the autumn could lead to pollutant accumulation, especially at HB, which is a new urban area surrounded by residential areas and a transportation hub. Alkanes were the dominant group at both HB and XB in both sampling periods, but the contribution of aromatic pollutants at HB in the autumn was much higher than that of the other alkanes (11.16-19.55%). Compared to other cities, BTEX pollution in Shuozhou was among the lowest levels in the world. Because of the high levels of aromatic pollutants, the ozone formation potential increased significantly at HB in the autumn. Using the ratio analyses to identify the age of the air masses and analyze the sources, the results showed that the atmospheric VOCs at XB were strongly influenced by the remote sources of coal combustion, while at HB in the spring and autumn were affected by the remote sources of coal combustion and local sources of vehicle emission, respectively. Source analysis conducted using the Positive Matrix Factorization (PMF) model at Shuozhou showed that coal combustion and vehicle emissions made the two largest contributions (29.98% and 21.25%, respectively) to atmospheric VOCs. With further economic restructuring, the influence of vehicle emissions on the air quality should become more significant, indicating that controlling vehicle emissions is key to reducing the air pollution.

  12. Characterizing Emissions of Volatile Organic Compounds (VOCs) from Oil and Natural Gas Operations in Haynesville, Fayetteville, and Marcellus Shale Regions via Aircraft Observations During SENEX 2013

    NASA Astrophysics Data System (ADS)

    Gilman, J.; Lerner, B. M.; Dumas, M.; Hughes, D.; Jaksich, A.; Hatch, C. D.; Graus, M.; Peischl, J.; Pollack, I. B.; Ryerson, T. B.; Holloway, J.; Trainer, M.; Aikin, K.; Kaiser, J.; Keutsch, F. N.; Wolfe, G. M.; Hanisco, T. F.; Warneke, C.; De Gouw, J. A.

    2013-12-01

    The 2013 SENEX (Southeast Nexus) field campaign took place in June and July 2013 with to ascertain how the interaction of natural and anthropogenic emissions influence climate change and air quality throughout the southeastern United States. Five of the research flights utilizing the NOAA WP-3D aircraft focused on areas of intensive oil and natural gas production from various shale plays. These areas included the Haynesville shale in eastern Texas and western Louisiana, the Fayetteville shale in northern Arkansas, and the Marcellus shale in western Pennsylvania. According to the U.S. Energy Information Administration's (EIA) Annual Energy Outlook 2013 report, (1) the Haynesville, Fayetteville, and Marcellus shale collectively account for approximately 75% of the dry shale gas produced in the U.S., and (2) shale gas is expected to provide the largest source of growth in the U.S. natural gas supply over the next few decades. Depending on the particular shale formation, raw natural gas can contain significant amounts of non-methane hydrocarbons in the form of natural gas liquids (e.g., ethane, propane, butanes) and natural gas condensate (e.g., pentanes, cycloalkanes, and aromatics). Trace gases including methane, aromatics, formaldehyde, other oxygenated VOCs, carbon monoxide, and nitrogen oxides were measured by multiple instruments aboard the NOAA WP-3D research aircraft. Up to 72 whole air samples (WAS) were collected in flight and analyzed in the field post-flight for a variety of volatile organic compounds (VOCs). Whole air samples provide a detailed chemical snapshot that can be combined with higher time-resolved measurements in order to provide a more comprehensive chemical analysis. In this presentation, we will compare the emissions composition of the Haynesville, Fayetteville, and Marcellus shale plays to investigate the relative importance of primary VOC emissions on the formation of secondary pollutants such as ozone, oxygenated VOCs, and secondary

  13. Ambient air/near-field measurements of methane and Volatile Organic Compounds (VOCs) from a natural gas facility in Northern Europe

    NASA Astrophysics Data System (ADS)

    Baudic, Alexia; Gros, Valérie; Bonsang, Bernard; Baisnee, Dominique; Vogel, Félix; Yver Kwok, Camille; Ars, Sébastien; Finlayson, Andrew; Innocenti, Fabrizio; Robinson, Rod

    2015-04-01

    Since the 1970's, the natural gas consumption saw a rapid growth in large urban centers, thus becoming an important energy resource to meet continuous needs of factories and inhabitants. Nevertheless, it can be a substantial source of methane (CH4) and pollutants in urban areas. For instance, we have determined that about 20% of Volatile Organic Compounds (VOCs) in downtown Paris are originating from this emission source (Baudic, Gros et al., in preparation). Within the framework of the "Fugitive Methane Emissions" (FuME) project (Climate-KIC, EIT); 2-weeks gas measurements were conducted at a gas compressor station in Northern Europe. Continuous ambient air measurements of methane and VOCs concentrations were performed using a cavity ring-down spectrometer (model G2201, Picarro Inc., Santa Clara, USA) and two portable GC-FID (Chromatotec, Saint-Antoine, France), respectively. On-site near-field samplings were also carried out at the source of two pipelines using stainless steel flasks (later analyzed with a laboratory GC-FID). The objective of this study aims to use VOCs as additional tracers in order to better characterize the fugitive methane emissions in a complex environment, which can be affected by several urban sources (road-traffic, others industries, etc.). Moreover, these measurements have allowed determining the chemical composition of this specific source. Our results revealed that the variability of methane and some VOCs was (rather) well correlated, especially for alkanes (ethane, propane, etc.). An analysis of selected events with strong concentrations enhancement was performed using ambient air measurements; thus allowing the preliminary identification of different emission sources. In addition, some flasks were also sampled in Paris to determine the local natural gas composition. A comparison between both was then performed. Preliminary results from these experiments will be presented here.

  14. Short-Term Intra-Subject Variation in Exhaled Volatile Organic Compounds (VOCs) in COPD Patients and Healthy Controls and Its Effect on Disease Classification

    PubMed Central

    Phillips, Christopher; Mac Parthaláin, Neil; Syed, Yasir; Deganello, Davide; Claypole, Timothy; Lewis, Keir

    2014-01-01

    Exhaled volatile organic compounds (VOCs) are of interest for their potential to diagnose disease non-invasively. However, most breath VOC studies have analyzed single breath samples from an individual and assumed them to be wholly consistent representative of the person. This provided the motivation for an investigation of the variability of breath profiles when three breath samples are taken over a short time period (two minute intervals between samples) for 118 stable patients with Chronic Obstructive Pulmonary Disease (COPD) and 63 healthy controls and analyzed by gas chromatography and mass spectroscopy (GC/MS). The extent of the variation in VOC levels differed between COPD and healthy subjects and the patterns of variation differed for isoprene versus the bulk of other VOCs. In addition, machine learning approaches were applied to the breath data to establish whether these samples differed in their ability to discriminate COPD from healthy states and whether aggregation of multiple samples, into single data sets, could offer improved discrimination. The three breath samples gave similar classification accuracy to one another when evaluated separately (66.5% to 68.3% subjects classified correctly depending on the breath repetition used). Combining multiple breath samples into single data sets gave better discrimination (73.4% subjects classified correctly). Although accuracy is not sufficient for COPD diagnosis in a clinical setting, enhanced sampling and analysis may improve accuracy further. Variability in samples, and short-term effects of practice or exertion, need to be considered in any breath testing program to improve reliability and optimize discrimination. PMID:24957028

  15. Root anoxia effects on physiology and emissions of volatile organic compounds (VOC) under short- and long-term inundation of trees from Amazonian floodplains.

    PubMed

    Bracho-Nunez, Araceli; Knothe, Nina Maria; Costa, Wallace R; Maria Astrid, Liberato R; Kleiss, Betina; Rottenberger, Stefanie; Piedade, Maria Teresa Fernandez; Kesselmeier, Jürgen

    2012-01-01

    Volatile organic compound (VOC) emissions are affected by a variety of biotic and abiotic factors such as light intensity, temperature, CO2 and drought. Another stress factor, usually overlooked but very important for the Amazon region, is flooding. We studied the exchange of VOCs in relation to CO2 exchange and transpiration of 8 common tree species from the Amazonian floodplain forest grown up from seeds using a dynamic enclosure system. Analysis of volatile organics was performed by PTR-MS fast online measurements. Our study confirmed emissions of ethanol and acetaldehyde at the beginning of root anoxia after inundation, especially in less anoxia adapted species such as Vatairea guianensis, but not for Hevea spruceana probably due to a better adapted metabolism. In contrast to short-term inundation, long-term flooding of the root system did not result in any emission of ethanol or/and acetaldehyde. Emission of other VOCs, such as isoprenoids, acetone, and methanol exhibited distinct behavior related to the origin (igapó or várzea type of floodplain) of the tree species. Also physiological activities exhibited different response patterns for trees from igapó or várzea. In general, isoprenoid emissions increased within the course of some days of short-term flooding. After a long period of waterlogging, VOC emissions decreased considerably, along with photosynthesis, transpiration and stomatal conductance. However, even under long-term testing conditions, two tree species did not show any significant decrease or increase in photosynthesis. In order to understand ecophysiological advantages of the different responses we need field investigations with adult tree species.

  16. [Air quality in schools - classroom levels of carbon dioxide (CO2), volatile organic compounds (VOC), aldehydes, endotoxins and cat allergen].

    PubMed

    Fromme, H; Heitmann, D; Dietrich, S; Schierl, R; Körner, W; Kiranoglu, M; Zapf, A; Twardella, D

    2008-02-01

    Children are assumed to be more vulnerable to health hazards and spend a large part of their time in schools. To assess the exposure situation in this microenvironment, we evaluated the indoor air quality in winter 2004/5 in 92 classrooms, and in 75 classrooms in summer 2005 in south Bavaria, Germany. Indoor air climate parameters (temperature, relative humidity), carbon dioxide (CO2) and various volatile organic compounds, aldehydes and ketones were measured. Additionally, cat allergen (Fel d1) and endotoxin (LAL-test) were analysed in the settled dust of school rooms. Data on room and building characteristics were collected by use of a standardised form. Only data collected during teaching hours were considered in analysis. The median indoor CO2 concentration in the classrooms ranged in the winter and summer period from 598 to 4 172 ppm and 480 to 1 875 ppm, respectively. While during the winter period in 92% of the classrooms the CO2 daily medians went above 1 000 ppm, the percentage of classrooms with increased CO2 concentration fell to 28% in summer. In winter, in 60% of classes the daily median CO2 concentration exceeded 1 500 ppm, while in summer this threshold was reached by only 9%. A high concentration of CO2 was associated with a high number of pupils, a low room surface area and a low room volume. The levels of total volatile organic compounds (TVOC) in classrooms ranged between 110 and 1 000 microg/m3 (median in winter 345 microg/m3, in summer 260 microg/m3). Acetone, formaldehyde and acetaldehyde were measured in concentrations from 14.0 to 911 microg/m3, from 3.1 to 46.1 microg/m3, and from 2.9 to 78 microg/m3, respectively. The other aldehydes were detected in minor amounts only. The median Fel d1 level in winter was 485 ng/g dust (20 to 45 160 ng/g) and in summer it was 417 ng/g (40-7 470 ng/g). We observed no marked differences between the two sampling periods and between smooth floors and rooms with carpeted floors. No differences were found

  17. Measurements of volatile organic compounds (VOCs) at the puy de Dôme research station (France, 1465m a.s.l.).

    NASA Astrophysics Data System (ADS)

    Colomb, A.; Gaimoz, C.; Fleuret, J.; Jacob, V.; Bouvier, L.; Pichon, J.-M.; Picard, D.; Ribeiro, M.; Freney, E.; Asmi, E.; Hervo, M.; Rose, C.; Jaffrezo, J.-L.; Sellegri, K.

    2012-04-01

    The high altitude puy de Dôme research station is located in central France (45° 46' N, 2° 57' E, 1465 m a.s.l.), 16km away from the city of Clermont-Ferrand. This station has been classified as representative background. At the summit, meteorological parameters including wind speed and direction, temperature, pressure, relative humidity and radiation, atmospheric trace gases (O3, NOx, SO2, CO2, CO), and aerosol physical, optical and chemical properties (particle size, black carbon, mass,... Selected volatile organic compounds (VOCs, including a large set of non-methane hydrocarbons and some terpenes (isoprene, α-pinene, …) and some oxygenated and halogenated compounds) were measured during intensive campaigns in summer 2010, spring 2011, summer 2011 and winter 2012. The analysis of VOCs collected on Tenax/Carbosieve III cartridges was achieved by using thermo-desorption coupled gas-chromatography with mass spectrometry (GC-MS). In order to determine the transport pathways of the air masses prior to arriving at the pdD site, the Hybrid Single Particle Langrangian Trajectory (HYSPLIT) model was used. Trajectories were classified according to their predominant transport direction prior to measurement as either continental (C), marine (M), marine modified (Mod), Mediterranean (Med), or mixed depending on their pathways. The results presented here are discussed in terms of observed levels, diurnal variability and sources influence. Different methods, including examination of ratio between compounds, comparison with other tracers (CO, BC, …) or other variables (temperature, air masses origins, planetary boundary layer height,…), are used to identify main parameters influencing VOCs variability.

  18. Particulate organic compounds emitted from motor vehicle exhaust and in the urban atmosphere

    NASA Astrophysics Data System (ADS)

    Fraser, Matthew P.; Cass, Glen R.; Simoneit, Bernd R. T.

    The emission rate of particle-phase petroleum biomarkers in vehicular exhaust compared to the concentrations of these biomarkers in ambient air is used to determine the particulate organic compound concentration due to primary particle emissions from motor vehicles in the southern California atmosphere. A material balance on the organic particulate matter emitted from motor vehicle traffic in a Los Angeles highway tunnel first is constructed to show the proportion which is solvent-extractable and which will elute from a GC column, the ratio of resolved to unresolved compound mass, the portion of the resolved material that can be identified as single organic compounds, and the contribution of different classes of organic compounds to the overall identified fraction. It is shown that the outdoor ambient concentrations of the petroleum biomarkers track primary emissions measured in the highway tunnel, confirming that direct emissions of these compounds from vehicles govern the observed ambient petroleum biomarker concentrations. Using organic chemical tracer techniques, the portion of fine organic particulate matter in the Los Angeles atmosphere which is attributable to direct particle emissions from vehicle exhaust is calculated to vary from 7.5 to 18.3% at different sites throughout the air basin during a summertime severe photochemical smog episode. A similar level of variation in the contribution of primary motor vehicle exhaust to fine particulate organic matter concentrations during different times of day is seen. While peak atmospheric concentrations of fine particulate organic carbon are observed during the 1200-1600 PDT afternoon sampling period, only 6.3% of that material is apportioned to the directly emitted particles from vehicle exhaust. During the morning traffic peak between 0600-1000 PDT, 19.1% of the fine particulate organic material is traced to primary emissions from motor vehicles.

  19. Comparison of Adsorption/Desorption of Volatile Organic Compounds (VOCs) on Electrospun Nanofibers with Tenax TA for Potential Application in Sampling

    PubMed Central

    Chu, Lanling; Deng, Siwei; Zhao, Renshan; Deng, Jianjun; Kang, Xuejun

    2016-01-01

    The objective of this study was to compare the adsorption/desorption of target compounds on homemade electrospun nanofibers, polystyrene (PS) nanofibers, acrylic resin (AR) nanofibers and PS-AR composite nanofibers with Tenax TA. Ten volatile organic compounds (VOCs) were analyzed by preconcentration onto different sorbents followed by desorption (thermal and solvent orderly) and analysis by capillary gas chromatography. In comparison to Tenax TA, the electrospun nanofibers displayed a significant advantage in desorption efficiency and adsorption selectivity. Stability studies were conducted as a comparative experiment between PS-AR nanofibers and Tenax TA using toluene as the model compound. No stability problems were observed upon storage of toluene on both PS-AR nanofibers and Tenax TA over 60 hours period when maintained in an ultra-freezer (−80°C). The nanofibers provided slightly better stability for the adsorbed analytes than Tenax TA under other storage conditions. In addition, the nanofibers also provided slightly better precision than Tenax TA. The quantitative adsorption of PS-AR nanofibers exhibited a good linearity, as evidenced by the 0.988–0.999 range of regression coefficients (R). These results suggest that for VOCs sampling the electrospun nanofibers can be a potential ideal adsorbent. PMID:27776140

  20. Comparison of Adsorption/Desorption of Volatile Organic Compounds (VOCs) on Electrospun Nanofibers with Tenax TA for Potential Application in Sampling.

    PubMed

    Chu, Lanling; Deng, Siwei; Zhao, Renshan; Deng, Jianjun; Kang, Xuejun

    2016-01-01

    The objective of this study was to compare the adsorption/desorption of target compounds on homemade electrospun nanofibers, polystyrene (PS) nanofibers, acrylic resin (AR) nanofibers and PS-AR composite nanofibers with Tenax TA. Ten volatile organic compounds (VOCs) were analyzed by preconcentration onto different sorbents followed by desorption (thermal and solvent orderly) and analysis by capillary gas chromatography. In comparison to Tenax TA, the electrospun nanofibers displayed a significant advantage in desorption efficiency and adsorption selectivity. Stability studies were conducted as a comparative experiment between PS-AR nanofibers and Tenax TA using toluene as the model compound. No stability problems were observed upon storage of toluene on both PS-AR nanofibers and Tenax TA over 60 hours period when maintained in an ultra-freezer (-80°C). The nanofibers provided slightly better stability for the adsorbed analytes than Tenax TA under other storage conditions. In addition, the nanofibers also provided slightly better precision than Tenax TA. The quantitative adsorption of PS-AR nanofibers exhibited a good linearity, as evidenced by the 0.988-0.999 range of regression coefficients (R). These results suggest that for VOCs sampling the electrospun nanofibers can be a potential ideal adsorbent.

  1. Volatile compounds emitted by diverse phytopathogenic microorganisms promote plant growth and flowering through cytokinin action.

    PubMed

    Sánchez-López, Ángela María; Baslam, Marouane; De Diego, Nuria; Muñoz, Francisco José; Bahaji, Abdellatif; Almagro, Goizeder; Ricarte-Bermejo, Adriana; García-Gómez, Pablo; Li, Jun; Humplík, Jan F; Novák, Ondřej; Spíchal, Lukáš; Doležal, Karel; Baroja-Fernández, Edurne; Pozueta-Romero, Javier

    2016-12-01

    It is known that volatile emissions from some beneficial rhizosphere microorganisms promote plant growth. Here we show that volatile compounds (VCs) emitted by phylogenetically diverse rhizosphere and non-rhizhosphere bacteria and fungi (including plant pathogens and microbes that do not normally interact mutualistically with plants) promote growth and flowering of various plant species, including crops. In Arabidopsis plants exposed to VCs emitted by the phytopathogen Alternaria alternata, changes included enhancement of photosynthesis and accumulation of high levels of cytokinins (CKs) and sugars. Evidence obtained using transgenic Arabidopsis plants with altered CK status show that CKs play essential roles in this phenomenon, because growth and flowering responses to the VCs were reduced in mutants with CK-deficiency (35S:AtCKX1) or low receptor sensitivity (ahk2/3). Further, we demonstrate that the plant responses to fungal VCs are light-dependent. Transcriptomic analyses of Arabidopsis leaves exposed to A. alternata VCs revealed changes in the expression of light- and CK-responsive genes involved in photosynthesis, growth and flowering. Notably, many genes differentially expressed in plants treated with fungal VCs were also differentially expressed in plants exposed to VCs emitted by the plant growth promoting rhizobacterium Bacillus subtilis GB03, suggesting that plants react to microbial VCs through highly conserved regulatory mechanisms.

  2. Apparatus and method for reading two-dimensional electrophoretograms containing. beta. -ray-emitting labeled compounds

    SciTech Connect

    Anderson, H.L.; Kinnison, W.W.; Lillberg, J.W.

    1987-08-11

    An apparatus for reading flat, substantially planar two-dimensional gel electrophoretograms containing ..beta..-ray-emitting labeled compounds, the apparatus comprising in combination: a. a single, substantially flat and rectangular proportional chamber radiation detection means substantially parallel to and approximately coextensive with the gel electrophoretogram for receiving ..beta..-rays emitted from the electrophoretogram and cosmic rays and generating electrical signals according to the two dimensional coordinates of each ..beta..-ray and cosmic ray received thereby; b. substantially flat and rectangular scintillator means located nearby to the substantially flat and rectangular proportional chamber radiation detection means for detecting the incidence of cosmic rays on the substantially flat and rectangular proportional chamber radiation detection means and having an electrical output in response thereto, yet having substantially no sensitivity to the ..beta..-rays emitted from the gel; c. magnetic field generating means for providing a substantially uniform magnetic field having dimensions substantially coextensive with the rectangular dimension of the substantially flat and rectangular proportional chamber radiation detection means and passing substantially perpendicularly therethrough and through the scintillator means.

  3. Sorption capacity of ground tires for vapor-phase volatile organic compounds

    SciTech Connect

    Kim, J.Y.; Park, J.K.; Edil, T.B.; Jhung, J.K.

    1996-12-31

    Batch sorption tests were conducted to determine the partition coefficient of volatile organic compounds (VOCs) by ground tires. The partition coefficient in the vapor phase was estimated by dividing the partition coefficient in the aqueous phase by Henry`s law constant. Under a diluted condition VOCs are sorbed onto ground tires noncompetitively regardless of the existence of other VOCs. Polar compounds such as methylene chloride were less sorbed onto ground tires than nonpolar compounds. The vapor-phase partition coefficient was found to have a logarithmic relationship with the saturation vapor concentration. VOCs emitted from waste-water treatment facilities can be effectively retarded by the ground tires.

  4. The urban atmosphere as a non-point source for the transport of MTBE and other volatile organic compounds (VOCS) to shallow groundwater

    USGS Publications Warehouse

    Pankow, J.F.; Thomson, N.R.; Johnson, R.L.; Baehr, A.L.; Zogorski, J.S.

    1997-01-01

    Infiltration and dispersion (including molecular diffusion) can transport volatile organic compounds (VOCs) from urban air into shallow groundwater. The gasoline additive methyl-tert-butyl ether (MTBE) is of special interest because of its (1) current levels in some urban air, (2) strong partitioning from air into water, (3) resistance to degradation, (4) use as an octane-booster since the 1970s, (5) rapidly increasing use in the 1990s to reduce CO and O3 in urban air, and (6) its frequent detection rat lOW microgram per liter levels in shallow urban groundwater in Denver, New England, and elsewhere. Numerical simulations were conducted using a l-D model domain set in medium sand (depth to water table = 5 m) to provide a test of whether MTBE and other atmospheric VOCs could move to shallow groundwater within the 10-15 y time frame over which MTBE has now been used in large amounts. Degradation and sorption were assumed negligible. In case 1 (no infiltration, steady atmospheric source), 10 y was not long enough to permit significant VOC movement by diffusion into shallow groundwater. Case 2 considered a steady atmospheric source plus 36 cm/y of net infiltration; groundwater at 2 m below the water table became nearly saturated with atmospheric levels of VOC within 5 y. Case 3 was similar to case 2, but considered the source to be seasonal being 'on' for only 5 of 12 months each year, as with the use of MTBE during the winter fuel-oxygenate season; groundwater at 2 m below the water table became equilibrated with 5/12 of the 'source-on' concentration within 5 y. Cases 4 and 5 added an evapotranspiration (ET) loss of 36 cm/y, resulting in no net recharge. Case 4 took the ET from the surface, and case 5 took the ET from the capillary fringe at a depth of 3.5 m. Net VOC mass transfer to shallow groundwater after 5 y was less for both cases 4 and 5 than for case 3. However, it was significantly greater for cases 4 and 5 than for case 1, even though cases 1, 4, add 5 were

  5. On-road emission characteristics of VOCs from diesel trucks in Beijing, China

    NASA Astrophysics Data System (ADS)

    Yao, Zhiliang; Shen, Xianbao; Ye, Yu; Cao, Xinyue; Jiang, Xi; Zhang, Yingzhi; He, Kebin

    2015-02-01

    This paper is the first in our series of papers aimed at understanding the volatile organic compound (VOC) emissions of vehicles in Beijing by conducting on-board emission measurements. This paper focuses on diesel vehicles. In this work, 18 China III diesel vehicles, including seven light-duty diesel trucks (LDDTs), four medium-duty diesel trucks (MDDTs) and seven heavy-duty diesel trucks (HDDTs), were examined when the vehicles were driven on predesigned fixed test routes in Beijing in China using a portable emissions measurement system (PEMS). Tedlar bag sampling and 2,4-dinitrophenyhydrazine (DNPH) cartridge sampling were used to collect VOC species, and gas chromatography-mass spectrometry (GC/MS) and high-performance liquid chromatography (HPLC) were used to analyze these samples. We obtained the VOC emission factors and relative compositions for diesel trucks of different sizes under different driving patterns. In total, 64 VOC species were quantified in this study, including 25 alkanes, four alkenes, 13 aromatics, 13 carbonyls and nine other compounds. The emission factors of the total VOCs based on mileage traveled for HDDTs were higher than those of LDDTs and MDDTs. Carbonyls, aromatics and alkanes were the dominant VOC species. Carbonyls accounted for 42.7%-69.2% of the total VOCs in the three types of tested diesel trucks. The total VOC emission factors of the tested vehicles that were driven on non-highway routes were 1.5-2.0 times higher than those of the vehicles driven on the highway. As for the OFP calculation results, with increased vehicle size, the ozone formation potential presented an increasing trend. Among the VOC components, carbonyls were the primary contributor to OFP. In addition, the OFPs under non-highway driving cycles were 1.3-1.7 times those under highway driving cycles. The results of this study will be helpful in improving our understanding of VOCs emitted from on-road diesel trucks in China.

  6. Use of thermal desorption gas chromatography-olfactometry/mass spectrometry for the comparison of identified and unidentified odor active compounds emitted from building products containing linseed oil.

    PubMed

    Clausen, P A; Knudsen, H N; Larsen, K; Kofoed-Sørensen, V; Wolkoff, P; Wilkins, C K

    2008-11-14

    The emission of odor active volatile organic compounds (VOCs) from a floor oil based on linseed oil, the linseed oil itself and a low-odor linseed oil was investigated by thermal desorption gas chromatography combined with olfactometry and mass spectrometry (TD-GC-O/MS). The oils were applied to filters and conditioned in the micro emission cell, FLEC, for 1-3days at ambient temperature, an air exchange rate of 26.9h(-1) and a 30% relative humidity. These conditions resulted in dynamic headspace concentrations and composition of the odor active VOCs that may be similar to real indoor setting. Emission samples for TD-GC-O/MS analysis from the FLEC were on Tenax TA. Although many volatile VOCs were detected by MS, only the odor active VOCs are reported here. In total, 142 odor active VOCs were detected in the emissions from the oils. About 50 of the odor active VOCs were identified or tentatively identified by GC-MS. While 92 VOCs were detected from the oil used in the floor oil, only 13 were detected in the low-odor linseed oil. The major odor active VOCs were aldehydes and carboxylic acids. Spearmen rank correlation of the GC-O profiles showed that the odor profile of the linseed oil likely influenced the odor profile of the floor oil based on this linseed oil.

  7. The reduction of HNO3 by volatile organic compounds emitted by motor vehicles

    NASA Astrophysics Data System (ADS)

    Rutter, A. P.; Malloy, Q. G. J.; Leong, Y. J.; Gutierrez, C. V.; Calzada, M.; Scheuer, E.; Dibb, J. E.; Griffin, R. J.

    2014-04-01

    Nitric acid (HNO3) was reduced in a flow tube by volatile organic carbon compounds (VOCs) generated from engine oil vapor. The primary reaction product was believed to be HONO. The reaction was not enhanced when Teflon® Raschig rings were added to the flow tube to increase surface area, thereby showing the reaction to be homogeneous under the conditions studied. The HONO formation observed ranged between 0.1 and 0.6 ppb h-1, with a mean of 0.3 ± 0.1 ppb h-1, for typical HNO3 concentrations of 4-5 ppb and estimated concentrations of the reactive components in the engine oil vapor between 200 and 300 ppt. The observations in this study compare well to a recently published field study conducted in Houston that observed average formation rates of 0.6 ± 0.3 ppb h-1. Water vapor was found to decrease the HONO formation rate by ˜0.1 ppb h-1 for every 1% increase in the water mixing ratio.

  8. VOC Contamination in Hospital, from Stationary Sampling of a Large Panel of Compounds, in View of Healthcare Workers and Patients Exposure Assessment

    PubMed Central

    Bessonneau, Vincent; Mosqueron, Luc; Berrubé, Adèle; Mukensturm, Gaël; Buffet-Bataillon, Sylvie; Gangneux, Jean-Pierre; Thomas, Olivier

    2013-01-01

    Background We aimed to assess, for the first time, the nature of the indoor air contamination of hospitals. Methods and Findings More than 40 volatile organic compounds (VOCs) including aliphatic, aromatic and halogenated hydrocarbons, aldehydes, alcohols, ketones, ethers and terpenes were measured in a teaching hospital in France, from sampling in six sampling sites – reception hall, patient room, nursing care, post-anesthesia care unit, parasitology-mycology laboratory and flexible endoscope disinfection unit – in the morning and in the afternoon, during three consecutive days. Our results showed that the main compounds found in indoor air were alcohols (arithmetic means ± SD: 928±958 µg/m3 and 47.9±52.2 µg/m3 for ethanol and isopropanol, respectively), ethers (75.6±157 µg/m3 for ether) and ketones (22.6±20.6 µg/m3 for acetone). Concentrations levels of aromatic and halogenated hydrocarbons, ketones, aldehydes and limonene were widely variable between sampling sites, due to building age and type of products used according to health activities conducted in each site. A high temporal variability was observed in concentrations of alcohols, probably due to the intensive use of alcohol-based hand rubs in all sites. Qualitative analysis of air samples led to the identification of other compounds, including siloxanes (hexamethyldisiloxane, octamethyltrisiloxane, decamethylcyclopentasiloxane), anesthetic gases (sevoflurane, desflurane), aliphatic hydrocarbons (butane), esters (ethylacetate), terpenes (camphor, α-bisabolol), aldehydes (benzaldehyde) and organic acids (benzoic acid) depending on sites. Conclusion For all compounds, concentrations measured were lower than concentrations known to be harmful in humans. However, results showed that indoor air of sampling locations contains a complex mixture of VOCs. Further multicenter studies are required to compare these results. A full understanding of the exposure of healthcare workers and patients to complex

  9. Characterizing and mitigating emissions of volatile organic compounds from animal feeding operations

    USDA-ARS?s Scientific Manuscript database

    Volatile organic compounds (VOC) emitted from animal feeding operations negatively impact local and potentially regional air quality though the release of both odorous and ozone precursor molecules. Characterizing emissions of VOCs from AFOs is strongly influenced by both the method and location of ...

  10. Volatile organic compound emission from holm oak infested by gypsy moth larvae: evidence for distinct responses in damaged and undamaged leaves.

    PubMed

    Staudt, Michael; Lhoutellier, Louise

    2007-10-01

    Foliage of Quercus ilex L. (holm oak), a widespread Mediterranean species, constitutively emits large quantities of a complex genotype-dependent mixture of volatile organic compounds (VOCs). During a mass outbreak of gypsy moth (Lymantria dispar L.) in southern France, we examined the effects of gypsy moth feeding on VOC production from whole apices and single leaves of Q. ilex. Feeding induced the emission of new VOCs at rates up to 240 ng m(-2) s(-1) (16% of the total VOC release), which mainly consisted of sesquiterpenes, a homoterpene and a monoterpene alcohol. The new compounds were emitted after a delay of several hours following infestation and their production declined rapidly when caterpillars were removed. Undamaged leaves of infested trees emitted new VOCs, but with a different composition to those of damaged leaves and at lower rates. Neither caterpillars nor caterpillar excrement released VOCs. Emission of constitutive VOCs by undamaged leaves of infested trees temporary increased by up to 30%, whereas, in damaged leaves, they remained stable and decreased after some days when necrotic spots occurred around the feeding sites. In continuous light and at constant temperature, emissions of new VOCs showed a marked diurnal cycle, whereas those of constitutive VOCs did not. The results suggest that induced VOCs make a significant contribution to the atmospheric VOC load and may mediate trophic interactions. The observed differential local and systemic responses in composition, quantity and time courses of emissions mirror the existence of several regulation processes triggered by different signaling compounds and elicitors.

  11. Sensitivity-Based VOC Reactivity Calculation

    EPA Science Inventory

    Volatile Organic Compound (VOC) reactivity scales are used to compare the ozone-forming potentials of various compounds. The comparison allows for substitution of compounds to lessen formation of ozone from paints, solvents, and other products. Current reactivity scales for VOC c...

  12. Sensitivity-Based VOC Reactivity Calculation

    EPA Science Inventory

    Volatile Organic Compound (VOC) reactivity scales are used to compare the ozone-forming potentials of various compounds. The comparison allows for substitution of compounds to lessen formation of ozone from paints, solvents, and other products. Current reactivity scales for VOC c...

  13. Anthropogenic sources of VOC in a football stadium: Assessing human emissions in the atmosphere

    NASA Astrophysics Data System (ADS)

    Veres, Patrick R.; Faber, Peter; Drewnick, Frank; Lelieveld, Jos; Williams, Jonathan

    2013-10-01

    Measurements of gas-phase volatile organic compounds (VOCs), aerosol composition, carbon dioxide (CO2), and ozone (O3) were made inside Coface Arena in Mainz, Germany (49°59‧3″N, 8°13‧27″E) during a football match on April 20 2012. The VOC measurements were performed with a proton-transfer-reaction time-of-flight mass spectrometer (PTR-TOF-MS). Observed VOCs could be classified into several distinct source categories including (1) human respiration/breath, (2) ozonolysis of skin oils, and (3) cigarette smoke/combustion. In this work, we present a detailed discussion on the scale and potential impacts of VOCs emitted as a result of these sources and their contributions on local and larger scales. Human emissions of VOCs have a negligible contribution to the global atmospheric budget (˜1% or less) for all those quantified in this study. However, fluxes as high as 0.02 g m-2 h-1 and 2 × 10-4 g m-2 h-1, for ethanol and acetone respectively are observed, suggesting the potential for significant impact on local air chemistry and perhaps regional scales. This study suggests that even in outdoor environments, situations exist where VOCs emitted as a result of human presence and activity are an important component of local air chemistry.

  14. VOC emissions during outdoor ship painting and health-risk assessment

    NASA Astrophysics Data System (ADS)

    Malherbe, Laure; Mandin, Corinne

    Painting of ship external surfaces in building or repair shipyards generates significant emissions of volatile organic compounds (VOC) to the atmosphere. Such emissions have not been specifically regulated so far. The purpose of our study is therefore to evaluate the quantities and as far as possible the nature of the emitted VOC, to characterize the dispersion of these chemicals in the atmosphere and to assess the exposure and resulting health risks for surrounding populations. This study is focused on VOC emitted during outdoor work involving use of paints and solvents. VOC emissions are diffuse, since they come from the whole painted surfaces. A methodology for quantifying them is developed and tested, using information provided by ALSTOM—Chantiers de l'Atlantique and data found in paint technical sheets. Its reliability is checked against emission values established by ALSTOM or found in literature. Then, for two particular situations, construction on one hand, repair on the other hand, atmospheric dispersion of total VOC is simulated to assess the long-term impact (characterized by the plume extension and the annual mean concentrations) of these compounds. Finally, a health-risk assessment based on the estimates is carried out to evaluate the risks by inhalation for people living near the site. Considering the presumed composition of paints and the available reference toxicological values, total VOC are entirely assimilated to toluene. In both examples (construction and repair) and in the current state of knowledge, the calculated risk is not of health concern. Several ways for taking this study further are proposed: a more exhaustive collection of data relative to VOC and other substances contained in paints, on-site measurement of VOC in the ambient air, characterization of diffuse emissions related to other activities, such as purging or welding, and other pollutants, like particles.

  15. Impact of cigarette smoking on volatile organic compound (VOC) blood levels in the U.S. population: NHANES 2003-2004.

    PubMed

    Chambers, David M; Ocariz, Jessica M; McGuirk, Maureen F; Blount, Benjamin C

    2011-11-01

    The impact of cigarette smoking on volatile organic compound (VOC) blood levels is studied using 2003-2004 National Health and Nutrition Examination Survey (NHANES) data. Cigarette smoke exposure is shown to be a predominant source of benzene, toluene, ethylbenzene, xylenes and styrene (BTEXS) measured in blood as determined by (1) differences in central tendency and interquartile VOC blood levels between daily smokers [≥1 cigarette per day (CPD)] and less-than-daily smokers, (2) correlation among BTEXS and the 2,5-dimethylfuran (2,5-DMF) smoking biomarker in the blood of daily smokers, and (3) regression modeling of BTEXS blood levels versus categorized CPD. Smoking status was determined by 2,5-DMF blood level using a cutpoint of 0.014 ng/ml estimated by regression modeling of the weighted data and confirmed with receiver operator curve (ROC) analysis. The BTEXS blood levels among daily smokers were moderately-to-strongly correlated with 2,5-DMF blood levels (correlation coefficient, r, ranging from 0.46 to 0.92). Linear regression of the geometric mean BTEXS blood levels versus categorized CPD showed clear dose-response relationship (correlation of determination, R(2), ranging from 0.81 to 0.98). Furthermore, the pattern of VOCs in blood of smokers is similar to that reported in mainstream cigarette smoke. These results show that cigarette smoking is a primary source of benzene, toluene and styrene and an important source of ethylbenzene and xylene exposure for the U.S. population, as well as the necessity of determining smoking status and factors affecting dose (e.g., CPD, time since last cigarette) in assessments involving BTEXS exposure.

  16. Volatile organic compound emissions from silage systems

    USDA-ARS?s Scientific Manuscript database

    As a precursor to smog, emission of volatile organic compounds (VOCs) to the atmosphere is an environmental concern in some regions. The major source from farms is silage, with emissions coming from the silo face, mixing wagon, and feed bunk. The major compounds emitted are alcohols with other impor...

  17. Dual-emitting nanocomposites derived from rare-earth compound nanotubes for ratiometric fluorescence sensing applications.

    PubMed

    Sun, Tian-Ying; Zhang, Da-Quan; Yu, Xue-Feng; Xiang, Yang; Luo, Min; Wang, Jia-Hong; Tan, Guo-Long; Wang, Qu-Quan; Chu, Paul K

    2013-02-21

    A new class of ratiometric fluorescence sensors composed of rare-earth (RE) compound nanotubes is described. Polyethylenimine-coated yttrium hydroxide fluoride nanotubes (YHF NTs) that were synthesized hydrothermally exhibit highly efficient fluorescence when doped with RE ions. The polyethylenimine on the NTs facilitates the incorporation of phosphors such as quantum dots or organic dyes onto the NT surface to produce dual-emitting nanocomposites which are excellent ratiometric fluorescence sensors. The phosphor layer and underlying tubes in the nanocomposites act as the indicator and reference probes, respectively. This ratiometric fluorescence method which can be applied to the detection of heavy metals in solutions, temperature sensing, and pH sensing boasts high sensitivity and selectivity as well as better accuracy than traditional intensity-based fluorescence methods.

  18. Fungal volatile compounds induce production of the secondary metabolite Sodorifen in Serratia plymuthica PRI-2C.

    PubMed

    Schmidt, Ruth; Jager, Victor de; Zühlke, Daniela; Wolff, Christian; Bernhardt, Jörg; Cankar, Katarina; Beekwilder, Jules; Ijcken, Wilfred van; Sleutels, Frank; Boer, Wietse de; Riedel, Katharina; Garbeva, Paolina

    2017-04-13

    The ability of bacteria and fungi to communicate with each other is a remarkable aspect of the microbial world. It is recognized that volatile organic compounds (VOCs) act as communication signals, however the molecular responses by bacteria to fungal VOCs remain unknown. Here we perform transcriptomics and proteomics analyses of Serratia plymuthica PRI-2C exposed to VOCs emitted by the fungal pathogen Fusarium culmorum. We find that the bacterium responds to fungal VOCs with changes in gene and protein expression related to motility, signal transduction, energy metabolism, cell envelope biogenesis, and secondary metabolite production. Metabolomic analysis of the bacterium exposed to the fungal VOCs, gene cluster comparison, and heterologous co-expression of a terpene synthase and a methyltransferase revealed the production of the unusual terpene sodorifen in response to fungal VOCs. These results strongly suggest that VOCs are not only a metabolic waste but important compounds in the long-distance communication between fungi and bacteria.

  19. Indoor air VOC concentrations in suburban and rural New Jersey.

    PubMed

    Weisel, Clifford P; Alimokhtari, Shahnaz; Sanders, Paul F

    2008-11-15

    Indoor VOC air concentrations of many compounds are higher than outdoor concentrations due to indoor sources. However, most studies have measured residential indoor air in urban centers so the typical indoor air levels in suburban and rural regions have not been well characterized. Indoor VOC air concentrations were measured in 100 homes in suburban and rural areas in NJ to provide background levels for investigations of the impact from subsurface contamination sources. Of the 57 target compounds, 23 were not detected in any of the homes, and 14 compounds were detected in at least 50% of the homes with detection limits of approximately 1 microg/m3. The common compounds identified included aromatic and aliphatic hydrocarbons from mobile sources, halogenated hydrocarbons commonly used in consumer products or from chlorinated drinking water, acetone and 2-butanone emitted from cosmetic products, and Freons. Typical concentrations were in the low microg/m3 range, though values of tens, hundreds or even thousands of microg/m3 were measured in individual homes in which activities related to specific sources of VOCs were reported. Compounds with known similar sources were highly correlated. The levels observed are consistent with concentrations found in the air of urban homes.

  20. Dual-emitting nanocomposites derived from rare-earth compound nanotubes for ratiometric fluorescence sensing applications

    NASA Astrophysics Data System (ADS)

    Sun, Tian-Ying; Zhang, Da-Quan; Yu, Xue-Feng; Xiang, Yang; Luo, Min; Wang, Jia-Hong; Tan, Guo-Long; Wang, Qu-Quan; Chu, Paul K.

    2013-01-01

    A new class of ratiometric fluorescence sensors composed of rare-earth (RE) compound nanotubes is described. Polyethylenimine-coated yttrium hydroxide fluoride nanotubes (YHF NTs) that were synthesized hydrothermally exhibit highly efficient fluorescence when doped with RE ions. The polyethylenimine on the NTs facilitates the incorporation of phosphors such as quantum dots or organic dyes onto the NT surface to produce dual-emitting nanocomposites which are excellent ratiometric fluorescence sensors. The phosphor layer and underlying tubes in the nanocomposites act as the indicator and reference probes, respectively. This ratiometric fluorescence method which can be applied to the detection of heavy metals in solutions, temperature sensing, and pH sensing boasts high sensitivity and selectivity as well as better accuracy than traditional intensity-based fluorescence methods.A new class of ratiometric fluorescence sensors composed of rare-earth (RE) compound nanotubes is described. Polyethylenimine-coated yttrium hydroxide fluoride nanotubes (YHF NTs) that were synthesized hydrothermally exhibit highly efficient fluorescence when doped with RE ions. The polyethylenimine on the NTs facilitates the incorporation of phosphors such as quantum dots or organic dyes onto the NT surface to produce dual-emitting nanocomposites which are excellent ratiometric fluorescence sensors. The phosphor layer and underlying tubes in the nanocomposites act as the indicator and reference probes, respectively. This ratiometric fluorescence method which can be applied to the detection of heavy metals in solutions, temperature sensing, and pH sensing boasts high sensitivity and selectivity as well as better accuracy than traditional intensity-based fluorescence methods. Electronic supplementary information (ESI) available: EA and TGA profiles, emission spectra of YHF:Eu NTs. See DOI: 10.1039/c2nr33217e

  1. Measurement of VOC permeability of polymer bags and VOC solubility in polyethylene drum liner

    SciTech Connect

    Liekhus, K.J.; Peterson, E.S.

    1995-03-01

    A test program conducted at the Idaho National Engineering Laboratory (INEL) investigated the use of a transport model to estimate the volatile organic compound (VOC) concentration in the void volume of a waste drum. Unsteady-state VOC transport model equations account for VOC permeation of polymer bags, VOC diffusion across openings in layers of confinement, and VOC solubility in a polyethylene drum liner. In support of this program, the VOC permeability of polymer bags and VOC equilibrium concentration in a polyethylene drum liner were measured for nine VOCs. The VOCs used in experiments were dichloromethane, carbon tetrachloride, cyclohexane, toluene, 1,1,1-trichloroethane, methanol, 1,1,2-trichloro-1,2,2-trifluoroethane (Freon-113), trichloroethylene, and p-xylene. The experimental results of these measurements as well as a method of estimating both parameters in the absence of experimental data are described in this report.

  2. Effects of climate change on volatile organic compound emissions from soil and litter

    NASA Astrophysics Data System (ADS)

    Gray, C. M.; Fierer, N.

    2012-12-01

    Our knowledge of the variability and magnitude of volatile organic compound (VOC) emissions from soil and litter is relatively limited compared to what we know about VOC emissions from terrestrial plants. With climate change expecting to alter plant community composition, nitrogen (N) deposition rates, mean annual temperatures, and precipitation patterns, it is unknown how production and consumption of VOCs from litter and soil will respond. We spent the last four years quantifying VOC emissions from soil and litter, comparing VOC emissions to CO2 emissions, and identifying the biotic and abiotic controls on emission rates with both lab and field experiments using a proton transfer reaction mass spectrometer (PTR-MS). In all studies, methanol was the dominant VOC flux. VOC emissions were not driven by abiotic processes, as microbial sources accounted for 78% to 99% of the total VOC emissions from decomposing litter. Litter chemistry was correlated with the types of VOCs emitted and the net emissions of carbon as VOCs was found to be up to 88% of that emitted as CO2 suggesting that VOCs likely represent an important component of the carbon cycle in many terrestrial systems. Nitrogen additions drastically reduced VOC emissions from litter to near zero, though it is still not understood whether this was due to an increase in consumption or a decrease in production. Finally, field and lab experiments show that temperature and moisture are both important controls of certain VOC emissions from soils, but that the effects of these factors on VOC emissions are not necessarily equivalent to their effects on CO2 emissions. Together, these series of studies are moving us toward a predictive understanding of VOC emissions from soil and litter with the ultimate goal of incorporating these VOC emissions into global models of terrestrial VOC dynamics.

  3. Cut-induced VOC emissions from agricultural grasslands.

    PubMed

    Davison, B; Brunner, A; Ammann, C; Spirig, C; Jocher, M; Neftel, A

    2008-01-01

    The introduction of proton transfer reaction mass spectrometry (PTR-MS) for fast response measurements of volatile organic compounds (VOC) has enabled the use of eddy covariance methods to investigate VOC fluxes on the ecosystem scale. In this study PTR-MS flux measurements of VOC were performed over agricultural grassland during and after a cut event. Selected masses detected by the PTR-MS showed fluxes of methanol, acetaldehyde, and acetone. They were highest directly after cutting and during the hay drying phase. Simultaneously, significant fluxes of protonated ion masses 73, 81, and 83 were observed. Due to the limited identification of compounds with the PTR-MS technique, GC-MS and GC-FID-PTR-MS techniques were additionally applied. In this way, ion mass 73 could be identified as 2-butanone, mass 81 mainly as (Z)-3-hexenal, and mass 83 mainly as the sum of (Z)-3-hexenol and hexenyl acetates. Hexenal, hexenols, and the hexenyl acetates are mostly related to plant wounding during cutting. It was found that legume plants and forbs emit a higher number of different VOC species than graminoids.

  4. Pilot and Full Scale Measurements of VOC Emissions from Lumber Drying of Inland Northwest Species

    SciTech Connect

    Fritz, Brad G.; Lamb, Brian K.; Westberg, Halvor; Folk, Richard; Knighton, B; Grimsrud, E

    2004-07-01

    Volatile organic compounds (VOCs) are precursors to ground level ozone. Ground level ozone is the major component of photochemical smog, and has been linked to a variety of adverse health effects. These health effects include cancer, heart disease, pneumonia and death. In order to reduce ground level ozone, VOC emissions are being more stringently regulated. One VOC source that may come under regulation is lumber drying. Drying lumber is known to emit VOC into the atmosphere. This research evaluates the validity of VOC emission measurements from a small-scale kiln to approximate VOC emissions from kilns at commercial mills. We also report emission factors for three lumber species commonly harvested in the northwest United States (Douglas-fir, ponderosa pine, & grand fir). This work was done with a novel tracer ratio technique at a small laboratory kiln and a large commercial lumber drying facility. The measured emission factors were 0.51 g/kgOD for Douglas-fir, 0.7 g/kgOD for ponderosa pine, and 0.15 g/kgOD for grand fir. Aldehyde emission rates from lumber drying were also measured in some experiments. Results indicate that aldehyde emissions can constitute a significant percentage of the total VOC emissions.

  5. Pollution characteristics of volatile organic compounds, polycyclic aromatic hydrocarbons and phthalate esters emitted from plastic wastes recycling granulation plants in Xingtan Town, South China

    NASA Astrophysics Data System (ADS)

    Huang, De-Yin; Zhou, Shun-Gui; Hong, Wei; Feng, Wei-Feng; Tao, Liang

    2013-06-01

    With the aim to investigate the main pollution characteristics of exhaust gases emitted from plastic waste recycling granulation plants, mainly volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs) and phthalate esters (PAEs) were analyzed in Xingtan Town, the largest distribution center of plastic waste recycling in China. Both inside and outside the plants, the total concentrations of volatile monocyclic aromatic hydrocarbons (MAHs), PAHs and PAEs ranged from 2000 to 3000 μg m-3, 450 to 1200 ng m-3, and 200 to 1200 ng m-3, respectively. Their concentration levels inside the plants were higher than those outside the plants, and PAHs and PAEs were mainly distributed in the gas-phase. Notably, highly toxic benzo[a]pyrene (BaP) could be detected inside the plants, and harmful PAEs could be detected not only inside but also outside the plants, although PAEs are non-volatile. The exhaust gas composition and concentration were related to the plastic feedstock and granulation temperature.

  6. Influence of ozone concentration and temperature on ultra-fine particle and gaseous volatile organic compound formations generated during the ozone-initiated reactions with emitted terpenes from a car air freshener.

    PubMed

    Lamorena, Rheo B; Lee, Woojin

    2008-10-30

    Experiments were conducted to identify the emissions from the car air freshener and to identify the formation of ultra-fine particles and secondary gaseous compounds during the ozone-initiated oxidations with emitted volatile organic compounds (VOCs). The identified primary constituents emitted from the car air freshener in this study were alpha-pinene, beta-pinene, p-cymene, and limonene. Formation of ultra-fine particles (4.4-160 nm) was observed when ozone was injected into the chamber containing emitted monoterpenes from the air freshener. Particle number concentrations, particle mass concentrations, and surface concentrations were measured in time dependent experiments to describe the particle formation and growth within the chamber. The irritating secondary gaseous products formed during the ozone-initiated reactions include formaldehyde, acetaldehyde, acrolein, acetone, and propionaldehyde. Ozone concentration (50 and 100 ppb) and temperature (30 and 40 degrees C) significantly affect the formation of particles and gaseous products during the ozone-initiated reactions. The results obtained in this study provided an insight on the potential exposure of particles and irritating secondary products formed during the ozone-initiated reaction to passengers in confined spaces.

  7. Apparatus and method for reading two-dimensional electrophoretograms containing .beta.-ray-emitting labeled compounds

    DOEpatents

    Anderson, Herbert L.; Kinnison, W. Wayne; Lillberg, John W.

    1987-01-01

    Apparatus and method for electronically reading planar two dimensional .beta.-ray emitter-labeled gel electrophoretograms. A single, flat rectangular multiwire proportional chamber is placed in close proximity to the gel and the assembly placed in an intense uniform magnetic field disposed in a perpendicular manner to the rectangular face of the proportional chamber. Beta rays emitted in the direction of the proportional chamber are caused to execute helical motions which substantially preserve knowledge of the coordinates of their origin in the gel. Perpendicularly oriented, parallel wire, parallel plane cathodes electronically sense the location of the .beta.-rays from ionization generated thereby in a detection gas coupled with an electron avalanche effect resulting from the action of a parallel wire anode located therebetween. A scintillator permits the present apparatus to be rendered insensitive when signals are generated from cosmic rays incident on the proportional chamber. Resolution for concentrations of radioactive compounds in the gel exceeds 700 .mu.m. The apparatus and method of the present invention represent a significant improvement over conventional autoradiographic techniques in dynamic range, linearity and sensitivity of data collection. A concentration and position map for gel electrophoretograms having significant concentrations of labeled compounds and/or highly radioactive labeling nuclides can generally be obtained in less than one hour.

  8. Apparatus for reading two-dimensional electrophoretograms containing. beta. -ray-emitting labeled compounds

    DOEpatents

    Anderson, H.L.; Kinnison, W.W.; Lillberg, J.W.

    1985-04-30

    An apparatus and method for electronically reading planar two-dimensional ..beta..-ray emitter-labeled gel electrophoretograms. A single, flat rectangular multiwire proportional chamber is placed in close proximity to the gel and the assembly placed in an intense uniform magnetic field disposed in a perpendicular manner to the rectangular face of the proportional chamber. Beta rays emitted in the direction of the proportional chamber are caused to execute helical motions which substantially preserve knowledge the coordinates of their origin in the gel. Perpendicularly oriented, parallel wire, parallel plane cathodes electronically sense the location of the ..beta..-rays from ionization generated thereby in a detection gas coupled with an electron avalanche effect resulting from the action of a parallel wire anode located therebetween. A scintillator permits the present apparatus to be rendered insensitive when signals are generated from cosmic rays incident on the proportional chamber. Resolution for concentrations of radioactive compounds in the gel exceeds 700-..mu..m. The apparatus and method of the present invention represent a significant improvement over conventional autoradiographic techniques in dynamic range, linearity and sensitivity of data collection. A concentration and position map for gel electrophoretograms having significant concentrations of labeled compounds and/or highly radioactive labeling nuclides can generally be obtained in less than one hour.

  9. Flameless thermal destruction of VOCs

    SciTech Connect

    Hohl, H.M.

    1997-04-01

    A new technology controls volatile organic compounds (VOCs) emissions with high destruction efficiencies. This article describes the technology developed by Thermatrix, Inc. of San Jose, CA. The field proven flameless thermal oxidation (FTO) is capable of destroying over 99.99 percent of a wide range of organic air pollution. Topics covered include FTO technology, high destruction efficiencies, VOCs in wastewater from chemical manufacturing; refinery fugitive emissions.

  10. Characterization of trace gases measured over Alberta oil sands mining operations: 76 speciated C2-C10 volatile organic compounds (VOCs), CO2, CH4, CO, NO, NO2, NOy, O3 and SO2

    NASA Astrophysics Data System (ADS)

    Simpson, I. J.; Blake, N. J.; Barletta, B.; Diskin, G. S.; Fuelberg, H. E.; Gorham, K.; Huey, L. G.; Meinardi, S.; Rowland, F. S.; Vay, S. A.; Weinheimer, A. J.; Yang, M.; Blake, D. R.

    2010-12-01

    Oil sands comprise 30% of the world's oil reserves and the crude oil reserves in Canada's oil sands deposits are second only to Saudi Arabia. The extraction and processing of oil sands is much more challenging than for light sweet crude oils because of the high viscosity of the bitumen contained within the oil sands and because the bitumen is mixed with sand and contains chemical impurities such as sulphur. Despite these challenges, the importance of oil sands is increasing in the energy market. To our best knowledge this is the first peer-reviewed study to characterize volatile organic compounds (VOCs) emitted from Alberta's oil sands mining sites. We present high-precision gas chromatography measurements of 76 speciated C2-C10 VOCs (alkanes, alkenes, alkynes, cycloalkanes, aromatics, monoterpenes, oxygenated hydrocarbons, halocarbons and sulphur compounds) in 17 boundary layer air samples collected over surface mining operations in northeast Alberta on 10 July 2008, using the NASA DC-8 airborne laboratory as a research platform. In addition to the VOCs, we present simultaneous measurements of CO2, CH4, CO, NO, NO2, NOy, O3 and SO2, which were measured in situ aboard the DC-8. Carbon dioxide, CH4, CO, NO, NO2, NOy, SO2 and 53 VOCs (e.g., non-methane hydrocarbons, halocarbons, sulphur species) showed clear statistical enhancements (1.1-397×) over the oil sands compared to local background values and, with the exception of CO, were greater over the oil sands than at any other time during the flight. Twenty halocarbons (e.g., CFCs, HFCs, halons, brominated species) either were not enhanced or were minimally enhanced (<10%) over the oil sands. Ozone levels remained low because of titration by NO, and three VOCs (propyne, furan, MTBE) remained below their 3 pptv detection limit throughout the flight. Based on their correlations with one another, the compounds emitted by the oil sands industry fell into two groups: (1) evaporative emissions from the oil sands and its

  11. Volatile organic compounds (VOC), formaldehyde and nitrogen dioxide (NO2) in schools in Johor Bahru, Malaysia: Associations with rhinitis, ocular, throat and dermal symptoms, headache and fatigue.

    PubMed

    Norbäck, Dan; Hashim, Jamal Hisham; Hashim, Zailina; Ali, Faridah

    2017-08-15

    This paper studied associations between volatile organic compounds (VOC), formaldehyde, nitrogen dioxide (NO2) and carbon dioxide (CO2) in schools in Malaysia and rhinitis, ocular, nasal and dermal symptoms, headache and fatigue among students. Pupils from eight randomly selected junior high schools in Johor Bahru, Malaysia (N=462), participated (96%). VOC, formaldehyde and NO2 were measured by diffusion sampling (one week) and VOC also by pumped air sampling during class. Associations were calculated by multi-level logistic regression adjusting for personal factors, the home environment and microbial compounds in the school dust. The prevalence of weekly rhinitis, ocular, throat and dermal symptoms were 18.8%, 11.6%, 15.6%, and 11.1%, respectively. Totally 20.6% had weekly headache and 22.1% fatigue. Indoor CO2 were low (range 380-690 ppm). Indoor median NO2 and formaldehyde concentrations over one week were 23μg/m(3) and 2.0μg/m(3), respectively. Median indoor concentration of toluene, ethylbenzene, xylene, and limonene over one week were 12.3, 1.6, 78.4 and 3.4μg/m(3), respectively. For benzaldehyde, the mean indoor concentration was 2.0μg/m(3) (median<1μg/m(3)). Median indoor levels during class of benzene and cyclohexane were 4.6 and 3.7μg/m(3), respectively. NO2 was associated with ocular symptoms (p<0.001) and fatigue (p=0.01). Formaldehyde was associated with ocular (p=0.004), throat symptoms (p=0.006) and fatigue (p=0.001). Xylene was associated with fatigue (p<0.001) and benzaldehyde was associated with headache (p=0.03). In conclusion, xylene, benzaldehyde, formaldehyde and NO2 in schools can be risk factors for ocular and throat symptoms and fatigue among students in Malaysia. The indoor and outdoor levels of benzene were often higher than the EU standard of 5μg/m(3). Copyright © 2017. Published by Elsevier B.V.

  12. Short-chain oxygenated VOCs: Emission and uptake by plants and atmospheric sources, sinks, and concentrations

    NASA Astrophysics Data System (ADS)

    Seco, Roger; Peñuelas, Josep; Filella, Iolanda

    Emissions of volatile organic compounds (VOCs) have multiple atmospheric implications and play many roles in plant physiology and ecology. Among these VOCs, growing interest is being devoted to a group of short-chain oxygenated VOCs (oxVOCs). Technology improvements such as proton transfer reaction-mass spectrometry are facilitating the study of these hydrocarbons and new data regarding these compounds is continuously appearing. Here we review current knowledge of the emissions of these oxVOCs by plants and the factors that control them, and also provide an overview of sources, sinks, and concentrations found in the atmosphere. The oxVOCs reviewed here are formic and acetic acids, acetone, formaldehyde, acetaldehyde, methanol, and ethanol. In general, because of their water solubility (low gas-liquid partitioning coefficient), the plant-atmosphere exchange is stomatal-dependent, although it can also take place via the cuticle. This exchange is also determined by atmospheric mixing ratios. These compounds have relatively long atmospheric half-lives and reach considerable concentrations in the atmosphere in the range of ppbv. Likewise, under non-stressed conditions plants can emit all of these oxVOCs together at fluxes ranging from 0.2 up to 4.8 μg(C)g -1(leaf dry weight)h -1 and at rates that increase several-fold when under stress. Gaps in our knowledge regarding the processes involved in the synthesis, emission, uptake, and atmospheric reactivity of oxVOCs precludes the clarification of exactly what is conditioning plant-atmosphere exchange—and also when, how, and why this occurs—and these lacunae therefore warrant further research in this field.

  13. Impact of food intake on in vivo VOC concentrations in exhaled breath assessed in a caprine animal model.

    PubMed

    Fischer, Sina; Bergmann, Andreas; Steffens, Markus; Trefz, Phillip; Ziller, Mario; Miekisch, Wolfram; Schubert, Jochen S; Köhler, Heike; Reinhold, Petra

    2015-12-15

    Physiological processes within the body may change emitted volatile organic compound (VOC) composition, and may therefore cause confounding biological background variability in breath gas analyses. To evaluate the effect of food intake on VOC concentration patterns in exhaled breath, this study assessed the variability of VOC concentrations due to food intake in a standardized caprine animal model. VOCs in (i) alveolar breath gas samples of nine clinically healthy goats and (ii) room air samples were collected and pre-concentrated before morning feeding and repeatedly after (+60 min, +150 min, +240 min) using needle trap microextraction (NTME). Analysis of VOCs was performed by gas chromatography and mass spectrometry (GC-MS). Only VOCs with significantly higher concentrations in breath gas samples compared to room air samples were taken into consideration. Six VOCs that belonged to the chemical classes of hydrocarbons and alcohols were identified presenting significantly different concentrations before and after feeding. Selected hydrocarbons showed a concentration pattern that was characterized by an initial increase 60 min after food intake, and a subsequent gradual decrease. Results emphasize consideration of physiological effects on exhaled VOC concentrations due to food intake with respect to standardized protocols of sample collection and critical evaluation of results.

  14. [Preliminary study concerning emissions of the volatile organic compounds from cooking oils].

    PubMed

    He, Wan-Qing; Tian, Gang; Nie, Lei; Qu, Song; Li, Jing; Wang, Min-Yan

    2012-09-01

    Cooking oil fume is one of the important sources of atmospheric volatile organic compounds (VOCs), which are the key precursors of ozone and secondary organic aerosols in air. In this study, the production of cooking oil fume was simulated by heating typical pure vegetable oils (peanut oil, sunflower oil, soybean oil, olive oil and blend oil) at different temperatures in beakers to investigate the VOCs emission characteristics. The emitted VOCs were sampled with a Tenax adsorption tube and analyzed using GC-MS after thermal desorption. The results showed that the emission of VOCs increased with the increase of the heating temperature for all the investigated cooking oils, and at a given temperature, the blend oil emitted the lowest amount of VOCs. The VOCs emission intensity at different heating temperatures fitted well with binomial equations and ranged from 1.6-11.1 mg x (kg x min)(-1).

  15. EFFECTS OF PARTICLE EVAPORATION ON THE ANGULAR MOMENTUM OF THE EMITTING NUCLEUS FOR DEEP INELASTIC AND COMPOUND NUCLEAR REACTIONS

    SciTech Connect

    Blau, S.K.; Moretto, L.G.

    1980-09-01

    A model is developed which allows one to calculate analytically the angular momentum removed, and the angular momentum misalignment created by the evaporation of light particles from an excited nucleus. The mass, temperature, and angular momentum of the emitting nucleus are explicitly considered. The formalism applies equally well to heavy ion and compound nuclear reactions.

  16. Drosophila melanogaster as a model to characterize fungal volatile organic compounds.

    PubMed

    Inamdar, Arati A; Zaman, Taslim; Morath, Shannon U; Pu, David C; Bennett, Joan W

    2014-05-01

    Fungi are implicated in poor indoor air quality and may pose a potential risk factor for building/mold related illnesses. Fungi emit numerous volatile organic compounds (VOCs) as alcohols, esters, ethers, ketones, aldehydes, terpenoids, thiols, and their derivatives. The toxicity profile of these VOCs has never been explored in a model organism, which could enable the performance of high throughput toxicological assays and lead to a better understanding of the mechanism of toxicity. We have established a reductionist Drosophila melanogaster model to evaluate the toxicity of fungal VOCs. In this report, we assessed the toxicity of fungal VOCs emitted from living cultures of species in the genera, Trichoderma, Aspergillus, and Penicillium and observed a detrimental effect on larval survival. We then used chemical standards of selected fungal VOCs to assess their toxicity on larval and adult Drosophila. We compared the survival of adult flies exposed to these fungal VOCs with known industrial toxic chemicals (formaldehyde [37%], xylene, benzene, and toluene). Among the tested fungal VOC standards, the compounds with eight carbons (C8) caused greater truncation of fly lifespan than tested non-C8 fungal VOCs and industrial toxins. Our data validate the use of Drosophila melanogaster as a model with the potential to elucidate the mechanistic attributes of different toxic VOCs emitted by fungi and also to explore the potential link between reported human illnesses/symptoms and exposure to water damaged and mold contaminated buildings.

  17. Volatile Organic Compounds (VOCs) Measurements in Karachi, Pakistan (2006): a Comparison With Previous Urban Sampling Campaigns Worldwide.

    NASA Astrophysics Data System (ADS)

    Barletta, B.; Meinardi, S.; Khwaja, H. A.; Beyersdorf, A. J.; Baker, A. K.; Zou, S.; Rowland, F.; Blake, D. R.

    2008-12-01

    Mixing ratios of carbon monoxide (CO), carbon dioxide (CO2), methane (CH4), and 47 nonmethane hydrocarbons - NMHCs - (19 alkanes, 13 alkenes, ethyne, and 14 aromatics) were determined for ground level whole air samples collected during the winter of 2006 in Karachi, Pakistan. Pakistan is among the fastest growing economies in Asia, and Karachi is one of the largest cities in the world with a rapidly expanding population of over 14 million in the whole metropolitan area, and a large industrial base. Samples were collected in January 2006 throughout the urban area to characterize the overall air composition of the city, and along the busiest road to determine the traffic signature of Karachi. This sampling campaign follows a previous study carried out in the winter of 1998-1999 in the same city, when elevated concentrations of many NMHCs were observed. Exceptionally high levels of methane were still observed in 2006 with an average mixing ratio of 5.0 ppmv (6.3 ppmv were observed in 1999). The overall air composition of the Karachi urban environment characterized during this 2006 sampling is compared to 1999 aiming to highlight any possible change in the main VOC sources present throughout the city. In particular, we want to evaluate the impact of the heavy usage of natural gas on the overall air quality of Karachi and the recently increased use of liquefied petroleum gas (LPG) as alternative source of energy. We also compare the composition of the urban troposphere of Karachi to other major urban centers worldwide such as Guangzhou (China), Mexico City (Mexico), and Milan (Italy).

  18. Volatile organic compound (VOC) emissions characterization during the flow-back phase of a hydraulically refractured well in the Uintah Basin, Utah using mobile PTR-MS measurements

    NASA Astrophysics Data System (ADS)

    Geiger, F.; Warneke, C.; Brown, S. S.; De Gouw, J. A.; Dube, W. P.; Edwards, P.; Gilman, J.; Graus, M.; Helleis, F.; Kofler, J.; Lerner, B. M.; Orphal, J.; Petron, G.; Roberts, J. M.; Zahn, A.

    2014-12-01

    Ongoing improvements in advanced technologies for crude oil and natural gas extraction from unconventional reserves, such as directional drilling and hydraulic fracturing, have greatly increased the production of fossil fuels within recent years. The latest forecasts even estimate an enhancement of 56% in total natural gas production due to increased development of shale gas, tight gas and offshore natural gas resources from 2012 to 2040 with the largest contribution from shale formations [US EIA: Annual Energy Outlook 2014]. During the field intensive 'Energy and Environment - Uintah Basin Winter Ozone Study (UBWOS)', measurements of volatile organic compounds (VOCs) were made using proton-transfer-reactions mass spectrometry (PTR-MS) at the ground site Horse Pool and using a mobile laboratory in the Uintah Basin, Utah, which is a region well known for intense fossil fuel production. A reworked gas well in the Red Wash fields was sampled regularly within two weeks performing mobile laboratory measurements downwind of the well site. The well had been recently hydraulically refractured at that time and waste water was collected into an open flow-back pond. Very high mixing ratios of aromatic hydrocarbons (C6-C13) up to the ppm range were observed coming from condensate and flow-back reservoirs. The measurements are used to determine sources of specific VOC emissions originating from the different parts of the well site and mass spectra are used to classify the air composition in contrast to samples taken at the Horse Pool field site and crude oil samples from South Louisiana. Enhancement ratios and time series of measured peak values for aromatics showed no clear trend, which indicates changes in emissions with operations at the site.

  19. NICS report links VOCs to respiratory problems

    SciTech Connect

    Kirschner, E.

    1992-04-22

    Children who live near the chemical plants of Kanawha Valley, WV, suffer more acute and chronic respiratory aliments than those farther away, says a Harvard University School of Public Health report. In the $1-million, five-year study commissioned by the National Institute for Chemical Studies (NICS:Charleston, WV) and funded by the Environmental Protection Agency, proximity to chemical plants that emit volatile organic compounds (VOCs) was linked to higher incidence of asthma, acute eye irritation, shortness of breath, and chronic cough. The researchers say they adjusted for most other factors, such as parental smoking and petroleum. {open_quotes}The research hypothesis was whether children in the valley had more symptoms,{close_quotes} says NICS president Paul Hill. {open_quotes}Yes, there is a difference.{close_quotes} The study showed that some ailments were up to 28% more prevalent in children in the valley than in other Kanawha County children.

  20. VOC emission into the atmosphere by trees and leaf litter in Polish forests

    NASA Astrophysics Data System (ADS)

    Isidorov, V.; Smolewska, M.; Tyszkiewicz, Z.

    2009-04-01

    It is generally recognized at present that the vegetation of continents is the principal source of reactive volatile organic compounds (VOC) of the atmosphere. The upper limit of the evaluation of global phytogenic VOC is 1100-1500 Tg/yr (Isidorov, 1990; Guenther et al., 1995). Although these global evaluations showing the place of phytogenic emission among of other VOC sources are important, evaluations for individual countries are also very important. This poster represents the results of the estimation of VOC emission from Polish forests. Calculations took into account the composition and age of forests. According to our estimation, the total VOC emission by the arboreal vegetation differs from 190 to 750 kt/yr, depending of weather conditions in different years. There are only few studies conducted on decaying plant material as a source of atmospheric VOCs, but still they are able to give evidence of the importance of this source. For Polish forests, the litter mass is estimated to be (16-19)106 t/yr. These organic materials undergo decomposition by mesofauna and microorganisms. In these processes volatile organic compounds (VOC) stored in the litter and secondary metabolites of litter-destroying fungi are emitted into the atmosphere. The scale of the phenomenon makes leaf litter an important VOC source in the atmosphere. The filling of numerous gaps in researches of VOC emissions from decomposing leaf litter demands carrying out of long term field experiments in various climatic conditions. In this communication we report also the results of 3.5-year experiment on qualitative and quantitative GC-MS investigations of VOC emitted into the gas phase from leaves litter of some species of deciduous and coniferous trees of Polish forests. Apart from terpenes and their oxygenated derivatives, which are usual in plant tissues, leaf litter intensively emits vast amounts of lower alcohols and carbonyl compounds. We suppose that these volatile substances are products

  1. VOC emissions from residential combustion of Southern and mid-European woods

    NASA Astrophysics Data System (ADS)

    Evtyugina, Margarita; Alves, Célia; Calvo, Ana; Nunes, Teresa; Tarelho, Luís; Duarte, Márcio; Prozil, Sónia O.; Evtuguin, Dmitry V.; Pio, Casimiro

    2014-02-01

    Emissions of trace gases (carbon dioxide (CO2), carbon monoxide (CO), total hydrocarbons (THC)), and volatile organic compounds (VOCs) from combustion of European beech, Pyrenean oak and black poplar in a domestic woodstove and fireplace were studied. These woods are widely used as biofuel in residential combustion in Southern and mid-European countries. VOCs in the flue gases were collected in Tedlar bags, concentrated in sorbent tubes and analysed by thermal desorption-gas chromatography-flame ionisation detection (GC-FID). CO2 emissions ranged from 1415 ± 136 to 1879 ± 29 g kg-1 (dry basis). The highest emission factors for CO and THC, 115.8 ± 11.7 and 95.6 24.7 ± 6.3 g kg-1 (dry basis), respectively, were obtained during the combustion of black poplar in the fireplace. European beech presented the lowest CO and THC emission factors for both burning appliances. Significant differences in emissions of VOCs were observed among wood species burnt and combustion devices. In general the highest emission factors were obtained from the combustion of Pyrenean oak in the woodstove. Among the VOCs identified, benzene and related compounds were always the most abundant group, followed by oxygenated compounds and aliphatic hydrocarbons. The amount and the composition of emitted VOCs were strongly affected by the wood composition, the type of burning device and operating conditions. Emission data obtained in this work are useful for modelling the impact of residential wood combustion on air quality and tropospheric ozone formation.

  2. VOC concentration in Taiwan's household drinking water.

    PubMed

    Kuo, H W; Chiang, T F; Lo, I I; Lai, J S; Chan, C C; Wang, J D

    1997-12-03

    The objective of this study is to analyze volatile organic compound (VOC) concentrations in Taiwan's drinking water supply. Focusing on Taiwan's three major metropolitan areas--Taipei, Taichung and Kaohsiung (in the north, middle and south, respectively)--171 samples were taken from tap water and 68 from boiled water. Tests showed VOC concentrations were highest in Kaohsiung. This is due to different water sources and methods of treatment. Except for bromoform, trihalomethane (THM) concentrations were highest. Detection rates of toluene and 1,2-dichloroethane were slightly higher than other VOC compounds. VOC concentrations decreased significantly after water was boiled. THMs had a removal rate from 61% to 82%. The authors conclude that the three metropolitan areas contain significantly different levels of VOCs and that boiling can significantly reduce the presence of VOCs. Other sources of pollution that contaminate drinking water such as industrial plants and gas stations must be further investigated.

  3. Equilibration times, compound selectivity, and stability of diffusion samplers for collection of ground-water VOC concentrations

    USGS Publications Warehouse

    Vroblesky, D.A.; Campbell, T.R.

    2001-01-01

    Vapor-filled polyethylene diffusion samplers (typically used to locate discharge zones of volatile organic compound contaminated ground water beneath streams and lakes) and water-filled polyethylene diffusion bag samplers (typically used to obtain volatile organic compound concentrations in ground-water at wells) were tested to determine compound selectivity, equilibration times, and sample stability. The aqueous concentrations of several volatile organic compounds obtained from within water-filled diffusion samplers closely matched concentrations in ambient water outside the samplers. An exception was methyl-tert-butyl ether, which was detectable, but not reliably quantifiable using the diffusion samplers. The samplers equilibrated to a variety of volatile organic compounds within 24 h for vapor-filled passive diffusion vial samplers and within 48 h for water-filled passive diffusion bag samplers. Under field conditions, however, a longer equilibration time may be required to account for environmental disturbances caused by sampler deployment. An equilibrium period for both vapor- and water-filled diffusion samplers of approximately 2 weeks probably is adequate for most investigations in sandy formations. Longer times may be required for diffusion-sampler equilibration in poorly permeable sediment. The vapor-filled samplers should be capped and water from the diffusion bag samplers should be transferred to sampling vials immediately upon recovery to avoid volatilization losses of the gasses. ?? 2001 Elsevier Science Ltd.

  4. Probability of Elevated Volatile Organic Compound (VOC) Concentrations in Groundwater in the Eagle River Watershed Valley-Fill Aquifer, Eagle County, North-Central Colorado, 2006-2007

    USGS Publications Warehouse

    Rupert, Michael G.; Plummer, L. Niel

    2009-01-01

    This raster data set delineates the predicted probability of elevated volatile organic compound (VOC) concentrations in groundwater in the Eagle River watershed valley-fill aquifer, Eagle County, North-Central Colorado, 2006-2007. This data set was developed by a cooperative project between the U.S. Geological Survey, Eagle County, the Eagle River Water and Sanitation District, the Town of Eagle, the Town of Gypsum, and the Upper Eagle Regional Water Authority. This project was designed to evaluate potential land-development effects on groundwater and surface-water resources so that informed land-use and water management decisions can be made. This groundwater probability map and its associated probability maps was developed as follows: (1) A point data set of wells with groundwater quality and groundwater age data was overlaid with thematic layers of anthropogenic (related to human activities) and hydrogeologic data by using a geographic information system to assign each well values for depth to groundwater, distance to major streams and canals, distance to gypsum beds, precipitation, soils, and well depth. These data then were downloaded to a statistical software package for analysis by logistic regression. (2) Statistical models predicting the probability of elevated nitrate concentrations, the probability of unmixed young water (using chlorofluorocarbon-11 concentrations and tritium activities), and the probability of elevated volatile organic compound concentrations were developed using logistic regression techniques. (3) The statistical models were entered into a GIS and the probability map was constructed.

  5. Speciation of volatile organic compounds from poultry production

    USDA-ARS?s Scientific Manuscript database

    The air consent agreement between EPA and large animal feeding operations (AFO) is designed to determine at what level compounds are being emitted from these facilities. However, the methodology used for quantifying total non-methane hydrocarbons and speciation of volatile organic compounds (VOC) n...

  6. Volatile organic compound control technologies for compliance with the Clean Air Act

    SciTech Connect

    Wax, M.J.

    1995-12-31

    Chemical industry sources in the U.S. emit 1,800,000 tons/year of volatile organic compounds (VOC), which contribute to the formation of ground-level ozone (smog). Concern with VOC emissions is heightened because many of these also are among the 189 toxic air pollutants listed in the Clean Air Act. This brief overview will cover the VOC problem, particularly as it is reflected in Clean Air Act requirements for reduced VOC emissions from small chemical businesses. Specific topics to be discussed include the HON rule, state RACT rules, and the general strategies and control technologies which will allow cost-effective compliance with these rules.

  7. Fast online emission monitoring of volatile organic compounds (VOC) in wastewater and product streams (using stripping with direct steam injection).

    PubMed

    Schocker, Alexander; Lissner, Bert

    2012-03-01

    Open-loop stripping analysis (also referred to as dynamic headspace) is a very flexible and robust technology for online monitoring of volatile organic compounds in wastewater or coolant. However, the quality and reliability of the analytical results depend strongly on the temperature during the stripping process. Hence, the careful and constant heating of the liquid phase inside the stripping column is a critical parameter. In addition, this stripping at high temperatures extends the spectrum of traceable organics to less volatile and more polar compounds with detection limits down to the ppm-level. This paper presents a novel and promising approach for fast, efficient, and constant heating by the direct injection of process steam into the strip medium. The performance of the system is demonstrated for temperatures up to 75 °C and traces of various hydrocarbons in water (e.g., tetrahydrofuran, methanol, 1-propanol, n-butanol, ethylbenzene).

  8. Modeling VOC transport in simulated waste drums

    SciTech Connect

    Liekhus, K.J.; Gresham, G.L.; Peterson, E.S.; Rae, C.; Hotz, N.J.; Connolly, M.J.

    1993-06-01

    A volatile organic compound (VOC) transport model has been developed to describe unsteady-state VOC permeation and diffusion within a waste drum. Model equations account for three primary mechanisms for VOC transport from a void volume within the drum. These mechanisms are VOC permeation across a polymer boundary, VOC diffusion across an opening in a volume boundary, and VOC solubilization in a polymer boundary. A series of lab-scale experiments was performed in which the VOC concentration was measured in simulated waste drums under different conditions. A lab-scale simulated waste drum consisted of a sized-down 55-gal metal drum containing a modified rigid polyethylene drum liner. Four polyethylene bags were sealed inside a large polyethylene bag, supported by a wire cage, and placed inside the drum liner. The small bags were filled with VOC-air gas mixture and the VOC concentration was measured throughout the drum over a period of time. Test variables included the type of VOC-air gas mixtures introduced into the small bags, the small bag closure type, and the presence or absence of a variable external heat source. Model results were calculated for those trials where the VOC permeability had been measured. Permeabilities for five VOCs [methylene chloride, 1,1,2-trichloro-1,2,2-trifluoroethane (Freon-113), 1,1,1-trichloroethane, carbon tetrachloride, and trichloroethylene] were measured across a polyethylene bag. Comparison of model and experimental results of VOC concentration as a function of time indicate that model accurately accounts for significant VOC transport mechanisms in a lab-scale waste drum.

  9. Use of Compound-Specific Stable Isotope Analysis to Distinguish between Vapor Intrusion and Indoor Sources of VOC

    DTIC Science & Technology

    2013-12-01

    ORGANIZATION NAME(S) AND ADDRESS(ES) Environmental Security Technology Certification Program (ESTCP,4800 Mark Center Drive, Suite 17D08,Alexandria,VA,22350...volatile organic compound δ Delta, an isotope ratio measure DoD Department of Defense ESTCP Environmental Security Technology Certification...Program GC gas chromatography GSI GSI Environmental GW groundwater HC hydrocarbons IRMS isotope ratio mass spectrometer µg/L micrograms per

  10. Modeling the VOC emissions from interior latex paint applied to gypsum board

    SciTech Connect

    Guo, Z.; Fortmann, R.; Marfiak, S.; Tichenor, B.; Sparks, L.

    1997-09-01

    The paper discusses modeling volatile organic compound (VOC) emissions from indoor latex paint applied to gypsum board. An empirical source model for a porous substrate was developed that takes both the wet- and dry-stage emission into consideration. Tests in the U.S. EPA`s Source Characterization Laboratory showed that common interior surfaces such as gypsum board and carpet could absorb significant amounts of latex paint VOCS from the air, and that they were re-emitted very slowly. An indoor air quality model incorporating the source model, an irreversible sink model, and the air movement data obtained from tracer gas tests made satisfactory predictions for the VOC levels in a test house.

  11. Estimation of Biogenic VOC Emissions From Ecosystems in the Czech Republic

    NASA Astrophysics Data System (ADS)

    Zemankova, K.; Brechler, J.

    2008-12-01

    Volatile organic compounds (VOC) are one of the crucial elements in photochemical reactions in the atmosphere which lead to tropospheric ozone formation. While modelling concentration of low-level ozone proper information about VOC sources and sinks is necessary. VOC are emitted into the atmosphere both from anthropogenic and natural sources. It has been shown in previous studies (e.g. Simpson et al, 1995) that contribution of volatile organic compounds emitted from biogenic sources to total amount of VOC in the atmosphere can be significant. Our work focuses on estimation of VOC emissions from natural ecosystems, most importantly from forests, and its application in photochemical modelling. Preliminary results have shown that inclusion of biogenic emissions in model input data leads to improvement of resulting ozone concentration which encouraged us to work on detailed biogenic VOC emission estimation. Using grid of 1x1km CORINE Land Cover over the area of the Czech Republic, emissions from deciduous, coniferous and mixed forests were estimated aplying the algorithm of Guenther et al., 1995. According to data from Forest Management Institute each cell of model grid has been assigned a proportional composition of each of thirteen tree species which are the the main forest constituents in the Czech Republic. Aggregating data of tree species composition with land cover category emission factor of particular chemical compound (isoprene, monoterpenes) has been obtained for each cell. Annual emissions of VOC on hourly basis have been calculated for domain of the Czech Republic. Biogenic emissions of isoprene and monoterpenes were compared with the emission inventory of anthropogenic sources. The inventory is provided by Czech Hydrometeorological Institute and covers emissions from major stationary sources, area sources (including domestic heating) and mobile sources. Our results show that natural emissions are approximately half the amount of organic compounds emitted

  12. A study on dynamic volatile organic compound emission characterization of water-based paints.

    PubMed

    Chang, Yu-Min; Hu, Wei-Hsing; Fang, Wen-Bing; Chen, Shiao-Shing; Chang, Chang-Tang; Ching, Hsiao-Wei

    2011-01-01

    Volatile organic compounds (VOCs) emitted from surface coatings have caused growing public concern for air quality. Even the low-emitted VOC impact from water-based paints on indoor air quality in urban areas has caused concern. This paper presents experimental data using a mathematical model to simulate dynamic VOC emissions from water-based paints that is based on mass transfer and molecular diffusion theories. A series of field-analogous experiments were carried out to continuously measure the VOCs emitted from two typical water-based paints using a gas chromatography-flame-ionization detector monitor in an artificial wind tunnel system. In the study cases, the mass flux of VOCs emitted from the water-based paints was up to 50 microg/m2sec. It was found that the time needed to completely emit VOCs from water-based paints is just hundreds of seconds. However, the order of magnitude of the VOC emission rate from water-based paints is not lower than that from some dry building materials and solvent-based paints. The experimental data were used to produce a useful semiempirical correlation to estimate the VOC emission rates for water-based paints. This correlation is valid under appropriate conditions as suggested by this work with a statistical deviation of +/- 7.6%. With this correlation, it seems feasible to predict the dynamic emission rates for VOCs during a painting process. This correlation is applicable for assessing the hazardous air pollutant impact on indoor air quality or for environmental risk assessment. Associated with the dynamic VOC emission characterization, the air-exchange rate effect on the VOC emission rates is also discussed.

  13. DEVELOPING A NO-VOC WOOD TOPCOAT

    EPA Science Inventory

    The paper reports an evaluation of a new low-VOC (volatile organic compound) wood coating technology, its performance characteristics, and its application and emissions testing. The low-VOC wood coating selected for the project was a two-component, water-based epoxy coating. Poly...

  14. MEMBRANE BIOTREATMENT OF VOC-LADEN AIR

    EPA Science Inventory

    The paper discusses membrane biotreatment of air laden with volatile organic compounds (VOCs). Microporous flat-sheet and hollow-fiber membrane contactors were used to support air-liquid mass transfer interfaces. These modules were used in a two-step process to transfer VOCs fr...

  15. DEVELOPING A NO-VOC WOOD TOPCOAT

    EPA Science Inventory

    The paper reports an evaluation of a new low-VOC (volatile organic compound) wood coating technology, its performance characteristics, and its application and emissions testing. The low-VOC wood coating selected for the project was a two-component, water-based epoxy coating. Poly...

  16. MEMBRANE BIOTREATMENT OF VOC-LADEN AIR

    EPA Science Inventory

    The paper discusses membrane biotreatment of air laden with volatile organic compounds (VOCs). Microporous flat-sheet and hollow-fiber membrane contactors were used to support air-liquid mass transfer interfaces. These modules were used in a two-step process to transfer VOCs fr...

  17. Volatile Organic Compound Emissions from Humans Indoors.

    PubMed

    Tang, Xiaochen; Misztal, Pawel K; Nazaroff, William W; Goldstein, Allen H

    2016-12-06

    Research on the sources of indoor airborne chemicals has traditionally focused on outdoor air, building materials, furnishings, and activities such as smoking, cooking, and cleaning. Relatively little research has examined the direct role of occupant emissions, even though this source clearly contributes to indoor volatile organic compounds (VOCs) and influences indoor chemistry. In this work, we quantify occupant-related gaseous VOC emissions in a university classroom using a proton-transfer-reaction time-of-flight mass spectrometer. Time-resolved concentrations of VOCs in room air and supply air were measured continuously during occupied and unoccupied periods. The emission factor for each human-emitted VOC was determined by dividing the occupant-associated source rate by the corresponding occupancy. Among the most abundant species detected were compounds associated with personal care products. Also prominent were human metabolic emissions, such as isoprene, methanol, acetone, and acetic acid. Additional sources included human skin oil oxidation by ozone, producing compounds such as 4-oxopentanal (4-OPA) and 6-methyl-5-hepten-2-one (6-MHO). By mass, human-emitted VOCs were the dominant source (57%) during occupied periods in a well-ventilated classroom, with ventilation supply air the second most important (35%), and indoor nonoccupant emissions the least (8%). The total occupant-associated VOC emission factor was 6.3 mg h(-1) per person.

  18. Quantification of VOC emissions from paint spraying on a construction site using solid phase microextraction devices.

    PubMed

    Cheng, Wen-Hsi; Huang, Hsiao-Lin; Chen, Kang-Shin; Chang, Yu-Jen

    2017-09-18

    The objective of this study was to measure the emission of, and personal exposure to workers, volatile organic compound (VOC) during paint spraying on a construction site. Needle trap samplers (NTSs), which are a green solid phase microextraction sampling technology, were used to obtain air samples at a large music exhibition center. The standard active sampling method using charcoal tubes and a personal air pump, Method 1501, was simultaneously utilized at the sampling sites to assess the workers' VOC exposures. Analysis of the data thus obtained showed that benzene, toluene, ethylenebenzene, and xylenes (BTEXs) were the main emission compounds. Acetone and isobutyl alcohol, which are used as thinning solvents, were detected as minor emission compounds. The emitted concentrations of most compounds were lower than the legal emission limits in Taiwan except that of benzene, for which the 2-ppm time weighted average short-term exposure limit was exceeded. The packed divinylbenzene (DVB) in the NTS was observed under an environmental scanning electron microscope, and many fine aerosols were found to be deposited on the surface of the DVB adsorbents, causing VOC extraction efficiencies after the fifth sampling in the field to decline. Workers on construction sites should be protected from emissions of VOC and fine particulates to preserve their occupational health.

  19. A Non-targeted Metabolomics Approach Unravels the VOCs Associated with the Tomato Immune Response against Pseudomonas syringae.

    PubMed

    López-Gresa, María Pilar; Lisón, Purificación; Campos, Laura; Rodrigo, Ismael; Rambla, José Luis; Granell, Antonio; Conejero, Vicente; Bellés, José María

    2017-01-01

    Volatile organic compounds (VOCs) emitted by plants are secondary metabolites that mediate the plant interaction with pathogens and herbivores. These compounds may perform direct defensive functions, i.e., acting as antioxidant, antibacterial, or antifungal agents, or indirectly by signaling the activation of the plant's defensive responses. Using a non-targeted GC-MS metabolomics approach, we identified the profile of the VOCs associated with the differential immune response of the Rio Grande tomato leaves infected with either virulent or avirulent strains of Pseudomonas syringae DC3000 pv. tomato. The VOC profile of the tomato leaves infected with avirulent bacteria is characterized by esters of (Z)-3-hexenol with acetic, propionic, isobutyric or butyric acids, and several hydroxylated monoterpenes, e.g., linalool, α-terpineol, and 4-terpineol, which defines the profile of an immunized plant response. In contrast, the same tomato cultivar infected with the virulent bacteria strain produced a VOC profile characterized by monoterpenes and SA derivatives. Interestingly, the differential VOCs emission correlated statistically with the induction of the genes involved in their biosynthetic pathway. Our results extend plant defense system knowledge and suggest the possibility for generating plants engineered to over-produce these VOCs as a complementary strategy for resistance.

  20. Volatile organic compound emissions from dairy cows and their waste as measured by proton-transfer-reaction mass spectrometry.

    PubMed

    Shaw, Stephanie L; Mitloehner, Frank M; Jackson, Wendi; Depeters, Edward J; Fadel, James G; Robinson, Peter H; Holzinger, Rupert; Goldstein, Allen H

    2007-02-15

    California dairies house approximately 1.8 million lactating and 1.5 million dry cows and heifers. State air regulatory agencies view these dairies as a major air pollutant source, but emissions data are sparse, particularly for volatile organic compounds (VOCs). The objective of this work was to determine VOC emissions from lactating and dry dairy cows and their waste using an environmental chamber. Carbon dioxide and methane were measured to provide context for the VOCs. VOCs were measured by proton-transfer-reaction mass spectrometry (PTR-MS). The compounds with highest fluxes when cows plus waste were present were methanol, acetone + propanal, dimethylsulfide, and m/z 109 (likely 4-methyl-phenol). The compounds with highest fluxes from fresh waste (urine and feces) were methanol, m/z 109, and m/z 60 (likely trimethylamine). Ethanol fluxes are reported qualitatively, and several VOCs that were likely emitted (formaldehyde, methylamine, dimethylamine) were not detectable by PTR-MS. The sum of reactive VOC fluxes measured when cows were present was a factor of 6-10 less than estimates historically used for regulatory purposes. In addition, ozone formation potentials of the dominant VOCs were -10% those of typical combustion or biogenic VOCs. Thus dairy cattle have a comparatively small impact on ozone formation per VOC mass emitted.

  1. Temporal variation of VOC emission from solvent and water based wood stains

    NASA Astrophysics Data System (ADS)

    de Gennaro, Gianluigi; Loiotile, Annamaria Demarinis; Fracchiolla, Roberta; Palmisani, Jolanda; Saracino, Maria Rosaria; Tutino, Maria

    2015-08-01

    Solvent- and water-based wood stains were monitored using a small test emission chamber in order to characterize their emission profiles in terms of Total and individual VOCs. The study of concentration-time profiles of individual VOCs enabled to identify the compounds emitted at higher concentration for each type of stain, to examine their decay curve and finally to estimate the concentration in a reference room. The solvent-based wood stain was characterized by the highest Total VOCs emission level (5.7 mg/m3) that decreased over time more slowly than those related to water-based ones. The same finding was observed for the main detected compounds: Benzene, Toluene, Ethylbenzene, Xylenes, Styrene, alpha-Pinene and Camphene. On the other hand, the highest level of Limonene was emitted by a water-based wood stain. However, the concentration-time profile showed that water-based product was characterized by a remarkable reduction of the time of maximum and minimum emission: Limonene concentration reached the minimum concentration in about half the time compared to the solvent-based product. According to AgBB evaluation scheme, only one of the investigated water-based wood stains can be classified as a low-emitting product whose use may not determine any potential adverse effect on human health.

  2. Exchange of volatile organic compounds in the boreal forest floor

    NASA Astrophysics Data System (ADS)

    Aaltonen, Hermanni; Bäck, Jaana; Pumpanen, Jukka; Pihlatie, Mari; Hakola, Hannele; Hellén, Heidi; Aalto, Juho; Heinonsalo, Jussi; Kajos, Maija K.; Kolari, Pasi; Taipale, Risto; Vesala, Timo

    2013-04-01

    Terrestrial ecosystems, mainly plants, emit large amounts of volatile organic compounds (VOCs) into the atmosphere. In addition to plants, VOCs also have less-known sources, such as soil. VOCs are a very diverse group of reactive compounds, including terpenoids, alcohols, aldehydes and ketones. Due to their high reactivity, VOCs take part in formation and growth of secondary organic aerosols in the atmosphere and thus affect also Earth's radiation balance (Kulmala et al. 2004). We have studied boreal soil and forest floor VOC fluxes with chamber and snow gradient techniques we were developed. Spatial and temporal variability in VOC fluxes was studied with year-round measurements in the field and the sources of boreal soil VOCs in the laboratory with fungal isolates. Determination of the compounds was performed mass spectrometrically. Our results reveal that VOCs from soil are mainly emitted by living roots, above- and belowground litter and microbes. The strongest source appears to be litter, in which both plant residuals and decomposers play a role in the emissions. Soil fungi showed high emissions of lighter VOCs, like acetone, acetaldehyde and methanol, from isolates. Temperature and moisture are the most critical physical factors driving VOC fluxes. Since the environment in boreal forests undergoes strong seasonal changes, the VOC flux strength of the forest floor varies markedly during the year, being highest in spring and autumn. The high spatial heterogeneity of the forest floor was also clearly visible in VOC fluxes. The fluxes of other trace gases (CO2, CH4 and N2O) from soil, which are also related to the soil biological activity and physical conditions, did not show correlations with the VOC fluxes. These results indicate that emissions of VOCs from the boreal forest floor account for as much as several tens of percent, depending on the season, of the total forest ecosystem VOC emissions. This emphasises that forest floor compartment should be taken into

  3. Underestimated public health risks caused by overestimated VOC removal in wastewater treatment processes.

    PubMed

    Yang, Junchen; Wang, Kun; Zhao, Qingliang; Huang, Likun; Yuan, Chung-Shin; Chen, Wei-Hsiang; Yang, Wen-Bin

    2014-02-01

    The uncontrolled release of volatile organic compounds (VOCs) from wastewater treatment plants (WWTPs) and the adverse health effects on the public have been of increasing concern. In this study, a lab-scale bioreactor was prepared to analyze the mass distribution of three aromatic (benzene, toluene, and xylenes) and four chlorinated VOCs (chloroform, carbon tetrachloride, trichloroethylene, and tetrachloroethylene) among the air, water and sludge phases in wastewater treatment processes. The VOC distribution through a full-scale WWTP in northern China was further investigated with respect to the effects of seasonal temperature variations and treatment technologies, followed by the cancer risk assessment using a steady-state Gaussian plume model (Industrial Source Complex) to simulate the atmospheric behaviors of the VOCs emitted from the WWTP. It was found that three aromatic hydrocarbons, notably benzene, were more readily released from the wastewater into the atmosphere, whereas the chlorinated compounds except chloroform were mainly present in the water phase through the treatment processes. The primary clarifier was the technology releasing high levels of VOCs into the atmosphere from the wastewater. The extents of volatilization or biodegradation, two important mechanisms to remove VOCs from wastewater, appeared to be determined by the physicochemical characteristics of the compounds, as the influence of treatment technologies (e.g., aeration) and seasonal temperature variations was rather limited. More importantly, the people living in the areas even more than 4 km away from the WWTP were still potentially exposed to cancer risks exceeding the regulatory threshold limit. The findings described the complex nature of VOC emissions from WWTPs and quantitatively indicated that the associated health impacts on the public near the WWTPs could be severely underestimated, whereas their treatment efficiencies by wastewater treatment technologies were overestimated

  4. Electronic and optical properties of novel carbazole-based donor-acceptor compounds for applications in blue-emitting organic light-emitting diodes

    SciTech Connect

    Legaspi, Christian M.; Stubbs, Regan E.; Yaron, David J.; Peteanu, Linda A.; Sfeir, Matthew Y.; Kemboi, Abraham; Picker, Jesse; Fossum, Eric

    2015-08-20

    We report that organic light-emitting diodes (OLEDs) have received a significant attention over the past decade due to their energy-saving potential. We have recently synthesized two novel carbazole-based donor-acceptor compounds and analyzed their optical properties to determine their suitability for use as blue emitters in OLEDs. These compounds show remarkable photo-stability and high quantum yields in the blue region of the spectrum. In addition, they have highly solvatochromic emission. In non-polar solvents, bright, blue-shifted (λmax ≈ 398 nm), and highly structured emission is seen. With increasing solvent dielectric constant, the emission becomes weaker, red-shifted (λmax ≈ 507 nm), and broad. We aim to determine the underlying cause of these changes. Electronic structure calculations indicate the presence of multiple excited states with comparable oscillator strength. These states are of interest because there are several with charge-transfer (CT) character, and others centered on the donor moiety. We theorize that CT states play a role in the observed changes in emission lineshape and may promote charge mobility for electrofluorescence in OLEDs. In the future, we plan to use Stark spectroscopy to analyze the polarity of excited states and transient absorption spectroscopy to observe the dynamics in the excited state.

  5. Electronic and optical properties of novel carbazole-based donor-acceptor compounds for applications in blue-emitting organic light-emitting diodes

    DOE PAGES

    Legaspi, Christian M.; Stubbs, Regan E.; Yaron, David J.; ...

    2015-08-20

    We report that organic light-emitting diodes (OLEDs) have received a significant attention over the past decade due to their energy-saving potential. We have recently synthesized two novel carbazole-based donor-acceptor compounds and analyzed their optical properties to determine their suitability for use as blue emitters in OLEDs. These compounds show remarkable photo-stability and high quantum yields in the blue region of the spectrum. In addition, they have highly solvatochromic emission. In non-polar solvents, bright, blue-shifted (λmax ≈ 398 nm), and highly structured emission is seen. With increasing solvent dielectric constant, the emission becomes weaker, red-shifted (λmax ≈ 507 nm), and broad.more » We aim to determine the underlying cause of these changes. Electronic structure calculations indicate the presence of multiple excited states with comparable oscillator strength. These states are of interest because there are several with charge-transfer (CT) character, and others centered on the donor moiety. We theorize that CT states play a role in the observed changes in emission lineshape and may promote charge mobility for electrofluorescence in OLEDs. In the future, we plan to use Stark spectroscopy to analyze the polarity of excited states and transient absorption spectroscopy to observe the dynamics in the excited state.« less

  6. Case study: Vacuuming for VOCs

    SciTech Connect

    Das, A.; Mazowiecki, C.R.

    1996-06-01

    The soil-vapor extraction system, which draws VOC-laden vapors from the subsurface, has become a popular remediation tool. The soil-vapor extraction (SVE) system, also know as {open_quotes}venting,{close_quotes} has proven to be a popular and cost-effective choice to remediate sites contaminated with volatile organic compounds (VOCs) in the vadose zone. The SVE system includes airflow in the subsurface by applying a vacuum through extraction wells. The system is described in this article, with a report on performance monitoring included.

  7. Improvement of HS-SPME for analysis of volatile organic compounds (VOC) in water samples by simultaneous direct fiber cooling and freezing of analyte solution.

    PubMed

    Fries, Elke; Püttmann, Wilhelm

    2006-11-01

    The sensitivity and precision of headspace solid-phase micro extraction (HS-SPME) at an analyte solution temperature (T (as)) of +35 degrees C and a fiber temperature (T (fiber)) of +5 degrees C were compared with those for HS-SPME at T (as) and T (fiber) of -20 degrees C for analysis of the volatile organic compounds benzene, 1,1,1-trichloroethane, trichloroethylene, toluene, o-xylene, ethylbenzene, m/p-xylene, and tetrachloroethylene in water samples. The effect of simultaneous fiber cooling and analyte solution freezing during extraction was studied. The compounds are of different hydrophobicity, with octanol/water partition coefficients (Kow) ranging from 126 and 2511. During a first set of experiments the polydimethylsiloxane (PDMS) SPME fiber was cooled to +5 degrees C with simultaneous heating of the aqueous analyte solution to +35 degrees C. During a second set of experiments, both SPME fiber holder and samples were placed in a deep freezer maintained at -20 degrees C for a total extraction time of 30 min. After approximately 2 min the analyte solution in the vial began to freeze from the side inwards and from the bottom upwards. After approximately 30 min the solution was completely frozen. Analysis of VOC was performed by coupling HS-SPME to gas chromatography-mass spectrometry (GC-MS). In general, i.e. except for tetrachloroethylene, the sensitivity of HS-SPME increased with increasing compound hydrophobicity at both analyte solution and fiber temperatures. At T (as) of +35 degrees C and T (fiber) of +5 degrees C detection limits of HS-SPME were 0.5 microg L(-1) for benzene, 1,1,1-trichloroethane, trichloroethylene, and tetrachloroethylene, 0.125 microg L(-1) for toluene, and 0.025 microg L(-1) for ethylbenzene, m/p-xylene, and o-xylene. In the experiments with T (as) and T (fiber) of -20 degrees C, detection limits were reduced for compounds of low hydrophobicity (Kow<501), for example benzene, toluene, 1,1,1-trichloroethane, and trichloroethylene. In

  8. EVALUATION OF LOW-VOC LATEX PAINTS

    EPA Science Inventory

    The paper gives results of an evaluation of four commercially available low-VOC (volatile organic compound) latex paints as substitutes for conventional latex paints by assessing both their emission characteristics and their performance as coatings. Bulk analysis indicated that ...

  9. Philips VOCs signature — EDRN Public Portal

    Cancer.gov

    A combination of 22 breath volatile organic compounds (VOCs), predominantly alkanes, alkane derivatives, and benzene derivatives, that can discriminate between patients with and without lung cancer, regardless of stage (all p<0.0003).

  10. EVALUATION OF LOW-VOC LATEX PAINTS

    EPA Science Inventory

    The paper gives results of an evaluation of four commercially available low-VOC (volatile organic compound) latex paints as substitutes for conventional latex paints by assessing both their emission characteristics and their performance as coatings. Bulk analysis indicated that ...

  11. World Calibration Center for VOC (WCC-VOC), a new Facility for the WMO-GAW-Programme

    NASA Astrophysics Data System (ADS)

    Rappenglueck, B.-

    2002-12-01

    Volatile organic compounds (VOC) are recognized to be important precursors of tropospheric ozone as well as other oxidants and organic aerosols. In order to design effective control measures for the reduction of photooxidants, photochemical processes have to be understood and the sources of the precursors known. Reliable and representative measurements of VOCs are necessary to describe the anthropogenic and biogenic sources, to follow the photochemical degradation of VOCs in the troposphere. Measurement of VOCs is of key importance for the understanding of tropospheric chemistry. Tropospheric VOCs have been one of the recommended measurements to be made within the GAW programme. The purpose will be to monitor their atmospheric abundance, to characterize the various compounds with regard to anthropogenic and biogenic sources and to evaluate their role in the tropospheric ozone formation process. An international WMO/GAW panel of experts for VOC measurements developed the rational and objectives for this GAW activity and recommended the configuration and required activities of the WCC-VOC. In reflection of the complexity of VOC measurements and the current status of measurement technology, a "staged" approach was adopted. Stage 1 measurements: C2-C9 hydrocarbons, including alkanes, alkenes, alkynes, dienes and monocyclics. (The WCC-VOC operates currently under this mode). Stage 2 measurements: C10-C14 hydrocarbons, including higher homologs of the Stage 1 set as well as biogenic hydrocarbon compounds. Stage 3 measurements: Oxygenated VOCs, including alcohols, carbonyls, carboxylic acids. The Quality Assurance/Science Activity Centre (QA/SAC) Germany currently has established the World Calibration Centre for VOC (WCC-VOC). The WCC-VOC has operated in the research mode und has become operational recently. From now on, the WCC-VOC conducts one round-robin calibration audit per year at all global stations that measure VOCs and assists other stations in setting up VOC

  12. Influence of dry deposition of semi-volatile organic compounds (VOC) on secondary organic aerosol (SOA) formation in the Mexico City plume

    NASA Astrophysics Data System (ADS)

    Hodzic, Alma; Madronich, Sasha; Aumont, Bernard; Lee-Taylor, Julia; Karl, Thomas

    2013-04-01

    The dry deposition removal of organic compounds from the atmosphere and its impact on organic aerosol mass is currently unexplored and unaccounted for in chemistry-climate models. The main reason for this omission is that current models use simplified SOA mechanisms that lump precursors and their products into volatility bins, therefore losing information on other important properties of individual molecules (or groups) that are needed to calculate dry deposition. In this study, we apply the Generator of Explicit Chemistry and Kinetics of Organics in the Atmosphere (GECKO-A) to simulate SOA formation and estimate the influence of dry deposition of VOCs on SOA concentrations downwind of Mexico City. SOA precursors considered here include short- and long-chain alkanes (C3-25), alkenes, and light aromatics. The results suggest that 90% of SOA produced in Mexico City originates from the oxidation and partitioning of long-chain (C>12) alkanes, while the regionally exported SOA is almost equally produced from long-chain alkanes and from shorter alkanes and light aromatics. We show that dry deposition of oxidized gases is not an efficient sink for SOA, as it removes <5% of SOA within the city's boundary layer and ~15% downwind. We discuss reasons for this limited influence, and investigate separately the impacts on short and long-chain species. We show that the dry deposition is competing with the uptake of gases to the aerosol phase, and because dry deposition of submicron aerosols is slow, condensation onto particles protects organic gases from deposition and therefore increases their atmospheric burden and lifetime. In the absence of this condensation, ~50% of the regionally produced mass would have been dry-deposited.

  13. Signals of speciation: volatile organic compounds resolve closely related sagebrush taxa, suggesting their importance in evolution.

    PubMed

    Jaeger, Deidre M; Runyon, Justin B; Richardson, Bryce A

    2016-09-01

    Volatile organic compounds (VOCs) play important roles in the environmental adaptation and fitness of plants. Comparison of the qualitative and quantitative differences in VOCs among closely related taxa and assessing the effects of environment on their emissions are important steps to deducing VOC function and evolutionary importance. Headspace VOCs from five taxa of sagebrush (Artemisia, subgenus Tridentatae) growing in two common gardens were collected and analyzed using GC-MS. Of the 74 total VOCs emitted, only 15 were needed to segregate sagebrush taxa using Random Forest analysis with a low error of 4%. All but one of these 15 VOCs showed qualitative differences among taxa. Ordination of results showed strong clustering that reflects taxonomic classification. Random Forest identified five VOCs that classify based on environment (2% error), which do not overlap with the 15 VOCs that segregated taxa. We show that VOCs can discriminate closely related species and subspecies of Artemisia, which are difficult to define using molecular markers or morphology. Thus, it appears that changes in VOCs either lead the way or follow closely behind speciation in this group. Future research should explore the functions of VOCs, which could provide further insights into the evolution of sagebrushes.

  14. Air sparging: Effects of VOCs and soil properties on VOC volatilization

    SciTech Connect

    Chao, K.P.; Ong, S.K.

    1995-12-31

    The effect of the physical-chemical properties of volatile organic compounds (VOCs) and soil on the volatilization of VOCs during air sparging was investigated using a laboratory-scale air sparging system. The variables studied included two types of soils, three different VOCs, and various air flowrates. VOCs used were chloroform, trichloroethylene (TCE), and carbon tetrachloride. As expected, the percent removal efficiencies of VOCs over a 24-h period were proportional to the injected air flowrate and Henry`s law constant. Experimental results also indicated that beyond a certain air flowrate, the mass of TCE removed was similar for the two porous media used in the experiments. The VOCs volatilized from the porous media appeared to be limited by the interfacial surface area of the water-air interface of the air channels. However, other physical processes, such as diffusion, may also be limiting.

  15. Volatile Organic Compounds Emitted by Fungal Associates of Conifer Bark Beetles and their Potential in Bark Beetle Control.

    PubMed

    Kandasamy, Dineshkumar; Gershenzon, Jonathan; Hammerbacher, Almuth

    2016-09-01

    Conifer bark beetles attack and kill mature spruce and pine trees, especially during hot and dry conditions. These beetles are closely associated with ophiostomatoid fungi of the Ascomycetes, including the genera Ophiostoma, Grosmannia, and Endoconidiophora, which enhance beetle success by improving nutrition and modifying their substrate, but also have negative impacts on beetles by attracting predators and parasites. A survey of the literature and our own data revealed that ophiostomatoid fungi emit a variety of volatile organic compounds under laboratory conditions including fusel alcohols, terpenoids, aromatic compounds, and aliphatic alcohols. Many of these compounds already have been shown to elicit behavioral responses from bark beetles, functioning as attractants or repellents, often as synergists to compounds currently used in bark beetle control. Thus, these compounds could serve as valuable new agents for bark beetle management. However, bark beetle associations with fungi are very complex. Beetle behavior varies with the species of fungus, the stage of the beetle life cycle, the host tree quality, and probably with changes in the emission rate of fungal volatiles. Additional research on bark beetles and their symbiotic associates is necessary before the basic significance of ophiostomatoid fungal volatiles can be understood and their applied potential realized.

  16. T2VOC user`s guide

    SciTech Connect

    Falta, R.W.; Pruess, K.; Finsterle, S.; Battistelli, A.

    1995-03-01

    T2VOC is a numerical simulator for three-phase, three-component, non-isothermal flow of water, air, and a volatile organic compound (VOC) in multidimensional heterogeneous porous media. Developed at the Lawrence Berkeley Laboratory, T2VOC is an extension of the TOUGH2 general-purpose simulation program. This report is a self-contained guide to application of T2VOC to subsurface contamination problems involving nonaqueous phase liquids (NAPLs). It gives a technical description of the T2VOC code, including a discussion of the physical processes modeled, and the mathematical and numerical methods used. Detailed instructions for preparing input data are presented along with several illustrative sample problems.

  17. VOC transport in vented drums containing simulated waste sludge

    SciTech Connect

    Liekhus, K.J.; Gresham, G.L.; Rae, C.; Connolly, M.J.

    1994-02-01

    A model is developed to estimate the volatile organic compound (VOC) concentration in the headspace of the innermost layer of confinement in a lab-scale vented waste drum containing simulated waste sludge. The VOC transport model estimates the concentration using the measured VOC concentration beneath the drum lid and model parameters defined or estimated from process knowledge of drum contents and waste drum configuration. Model parameters include the VOC diffusion characteristic across the filter vent, VOC diffusivity in air, size of opening in the drum liner lid, the type and number of layers of polymer bags surrounding the waste, VOC permeability across the polymer, and the permeable surface area of the polymer bags. Comparison of model and experimental results indicates that the model can accurately estimate VOC concentration in the headspace of the innermost layer of confinement. The model may be useful in estimating the VOC concentration in actual waste drums.

  18. Characterization of semi-volatile organic compounds emitted during heating of nitrogen-containing plastics at low temperature.

    PubMed

    Watanabe, Mafumi; Nakata, Chisto; Wu, Wei; Kawamoto, Katsuya; Noma, Yukio

    2007-08-01

    Because of recent volume increases, appropriate management of plastic recycling, which generates various organic compounds, is required to ensure the chemical safety of the processes. The processing temperature and resin type are the important factors determining both the efficiency of the processes and the emission of chemicals. Therefore, we studied the thermal degradation of various plastics at various temperatures from 70 to 300 degrees C under oxygen-present conditions to identify the semi-volatile organic compounds (SVOCs) emitted and to understand their thermal behaviors. The plastics examined were nitrogen-containing resins, such as polyamide 6, polyurethane, melamine formaldehyde, urea formaldehyde and acrylonitrile-butadiene-styrene. Major commodity plastics were also investigated for comparison. In total, more than 500 SVOCs were detected as emissions from plastics. While various nitrogen-containing SVOCs were detected from nitrogen-containing resins, the major commodity plastics released only these, which possibly were included as additives. These results indicate that the nitrogen atoms in the SVOCs emitted originated from the resins and additives, and not from ambient air at low temperature. As a result of the detection of raw materials, degradation chemicals and by-products of the polymers in the emissions, we found that the variation in chemical species is dependent on the resins. Additives were also emitted from all the resins, meaning that these chemicals were also released to the environment at the temperature examined. In most cases, the numbers and concentrations of SVOCs increased with increasing heating temperature. The variation of thermal behaviors of SVOCs was related to the origins and chemical species of SVOCs.

  19. Plant specific volatile organic compound emission factors from young and mature leaves of Mediterranean vegetation

    NASA Astrophysics Data System (ADS)

    Bracho-Nunez, Araceli; Welter, Saskia; Staudt, Michael; Kesselmeier, Jürgen

    2010-05-01

    Terrestrial vegetation is the most important source of atmospheric volatile organic compounds (VOC) with significant influence on the chemistry and physics of the atmosphere. VOCs influence the oxidative capacity of the atmosphere and contribute to the formation and growth of secondary organic aerosols affecting cloud development and precipitation. The aim of our study was to investigate potential quantitative and qualitative differences in VOC emission patterns of young and mature leaves for nine typical Mediterranean plant species. The Mediterranean area was chosen due to its special diversity in VOC emitting plant species. Foliar isoprenoid emissions as well as emissions of oxygenated VOC like methanol and acetone were measured under standard light and temperature conditions during spring and summer 2008 at the CEFE-CNRS institute in Montpellier, France. A proton transfer reaction mass spectrometer (PTR-MS) was used for online measurement of VOCs. While PTR-MS is an excellent technique for fast chemical measurements it lacks specificity and compounds with the same mass cannot be distinguished. For this reason, cartridge samples were collected and afterwards analyzed with GC-FID. In parallel offline VOC analyses were performed with gas chromatography (GC) coupled to a mass spectrometer and flame ionization detector, enabling assignment of the observed PTR-MS mass to charge ratios (m/z) to specific identification based on the GC-FID retention times. Thus, combining the PTR-MS and GC-FID analyses enabled accurate and online identification of the VOCs emitted. The results emphasise that VOC emission is a developmentally regulated process and quantitative and qualitative variability is plant species specific. Leaf ontogeny clearly influenced not only the standard emission rate but also the VOC composition, with methanol being the major compound that contributes to the total VOC emissions in young leaves and maintaining or decreasing its contribution with maturity.

  20. Boreal forest fire emissions in fresh Canadian smoke plumes: C1-C10 volatile organic compounds (VOCs), CO2, CO, NO2, NO, HCN and CH3CN

    NASA Astrophysics Data System (ADS)

    Simpson, I. J.; Akagi, S. K.; Barletta, B.; Blake, N. J.; Choi, Y.; Diskin, G. S.; Fried, A.; Fuelberg, H. E.; Meinardi, S.; Rowland, F. S.; Vay, S. A.; Weinheimer, A. J.; Wennberg, P. O.; Wiebring, P.; Wisthaler, A.; Yang, M.; Yokelson, R. J.; Blake, D. R.

    2011-07-01

    Boreal regions comprise about 17 % of the global land area, and they both affect and are influenced by climate change. To better understand boreal forest fire emissions and plume evolution, 947 whole air samples were collected aboard the NASA DC-8 research aircraft in summer 2008 as part of the ARCTAS-B field mission, and analyzed for 79 non-methane volatile organic compounds (NMVOCs) using gas chromatography. Together with simultaneous measurements of CO2, CO, CH4, CH2O, NO2, NO, HCN and CH3CN, these measurements represent the most comprehensive assessment of trace gas emissions from boreal forest fires to date. Based on 105 air samples collected in fresh Canadian smoke plumes, 57 of the 80 measured NMVOCs (including CH2O) were emitted from the fires, including 45 species that were quantified from boreal forest fires for the first time. After CO2, CO and CH4, the largest emission factors (EFs) for individual species were formaldehyde (2.1 ± 0.2 g kg-1), followed by methanol, NO2, HCN, ethene, α-pinene, β-pinene, ethane, benzene, propene, acetone and CH3CN. Globally, we estimate that boreal forest fires release 2.4 ± 0.6 Tg C yr-1 in the form of NMVOCs, with approximately 41 % of the carbon released as C1-C2 NMVOCs and 21 % as pinenes. These are the first reported field measurements of monoterpene emissions from boreal forest fires, and we speculate that the pinenes, which are relatively heavy molecules, were detected in the fire plumes as the result of distillation of stored terpenes as the vegetation is heated. Their inclusion in smoke chemistry models is expected to improve model predictions of secondary organic aerosol (SOA) formation. The fire-averaged EF of dichloromethane or CH2Cl2, (6.9 ± 8.6) × 10-4 g kg-1, was not significantly different from zero and supports recent findings that its global biomass burning source appears to have been overestimated. Similarly, we found no evidence for emissions of chloroform (CHCl3) or methyl chloroform (CH3CCl3

  1. Both the adaxial and abaxial epidermal layers of the rose petal emit volatile scent compounds.

    PubMed

    Bergougnoux, Véronique; Caissard, Jean-Claude; Jullien, Frédéric; Magnard, Jean-Louis; Scalliet, Gabriel; Cock, J Mark; Hugueney, Philippe; Baudino, Sylvie

    2007-09-01

    The localization and timing of production and emission of scent was studied in different Rosa x hybrida cultivars, focusing on three particular topics. First, it was found that petals represent the major source of scent in R. x hybrida. In heavily scented cultivars, the spectrum and levels of volatiles emitted by the flower broadly correlated with the spectrum and levels of volatiles contained within the petal, throughout petal development. Secondly, analysis of rose cultivars that lacked a detectable scent indicated that the absence of fragrance was due to a reduction in both the biosynthesis and emission of scent volatiles. A cytological study, conducted on scented and non-scented rose cultivars showed that no major difference was visible in the anatomy of the petals either at small magnification in optical sections or in ultrathin sections observed by TEM. In particular, the cuticle of epidermal cells was not thicker in scentless cultivars. Thirdly, using two different techniques, solid/liquid phase extraction and headspace collection of volatiles, we showed that in roses, both epidermal layers are capable of producing and emitting scent volatiles, despite the different morphologies of the cells of these two tissues. Moreover, OOMT, an enzyme involved in scent molecule biosynthesis was localized in both epidermal layers.

  2. Modeling emissions of volatile organic compounds from silage

    USDA-ARS?s Scientific Manuscript database

    Photochemical smog is a major air pollution problem and a significant cause of premature death in the U.S. Smog forms in the presence of volatile organic compounds (VOCs), which are emitted primarily from industry and motor vehicles in the U.S. However, dairy farms may be an important source in so...

  3. Quantifying VOC emissions from East Asia using 10 years of satellite observations

    NASA Astrophysics Data System (ADS)

    Stavrakou, T.; Muller, J. F.; Bauwens, M.; De Smedt, I.; Van Roozendael, M.; Boersma, F.; van der A, R. J.; Pierre-Francois, C.; Clerbaux, C.

    2016-12-01

    China's emissions are in the spotlight of efforts to mitigate climate change and improve regional and city-scale air quality. Despite growing efforts to better quantify China's emissions, the current estimates are often poor or inadequate. Complementary to bottom-up inventories, inverse modeling of fluxes has the potential to improve those estimates through the use of atmospheric observations of trace gas compounds. As formaldehyde (HCHO) is a high-yield product in the oxidation of most volatile organic compounds (VOCs) emitted by anthropogenic and natural sources, satellite observations of HCHO hold the potential to inform us on the spatial and temporal variability of the underlying VOC sources. The 10-year record of space-based HCHO column observations from the OMI instrument is used to constrain VOC emission fluxes in East Asia in a source inversion framework built on the IMAGES chemistry-transport model and its adjoint. The interannual and seasonal variability, spatial distribution and potential trends of the top-down VOC fluxes (anthropogenic, pyrogenic and biogenic) are presented and confronted to existing emission inventories, satellite observations of other species (e.g. glyoxal and nitrogen oxides), and past studies.

  4. Evaluation of volatile organic compound (VOC) blank data and application of study reporting levels to groundwater data collected for the California GAMA Priority Basin Project, May 2004 through September 2010

    USGS Publications Warehouse

    Fram, Miranda S.; Olsen, Lisa D.; Belitz, Kenneth

    2012-01-01

    Volatile organic compounds (VOCs) were analyzed in quality-control samples collected for the California Groundwater Ambient Monitoring and Assessment (GAMA) Program Priority Basin Project. From May 2004 through September 2010, a total of 2,026 groundwater samples, 211 field blanks, and 109 source-solution blanks were collected and analyzed for concentrations of 85 VOCs. Results from analyses of these field and source-solution blanks and of 2,411 laboratory instrument blanks during the same time period were used to assess the quality of data for the 2,026 groundwater samples. Eighteen VOCs were detected in field blanks or source-solution blanks: acetone, benzene, bromodichloromethane, 2-butanone, carbon disulfide, chloroform, 1,1-dichloroethene, dichloromethane, ethylbenzene, tetrachloroethene, styrene, tetrahydrofuran, toluene, trichloroethene, trichlorofluoromethane, 1,2,4-trimethylbenzene, m- and p-xylenes, and o-xylene. The objective of the evaluation of the VOC-blank data was to determine if study reporting levels (SRLs) were needed for any of the VOCs detected in blanks to ensure the quality of the data from groundwater samples. An SRL is equivalent to a raised reporting level that is used in place of the reporting level used by the analyzing laboratory [long‑term method detection level (LT-MDL) or laboratory reporting level (LRL)] to reduce the probability of reporting false-positive detections. Evaluation of VOC-blank data was done in three stages: (1) identification of a set of representative quality‑control field blanks (QCFBs) to be used for calculation of SRLs and identification of VOCs amenable to the SRL approach, (2) evaluation of potential sources of contamination to blanks and groundwater samples by VOCs detected in field blanks, and (3) selection of appropriate SRLs from among four potential SRLs for VOCs detected in field blanks and application of those SRLs to the groundwater data. An important conclusion from this study is that to ensure the

  5. Aromatic VOCs global influence in the ozone production

    NASA Astrophysics Data System (ADS)

    Cabrera-Perez, David; Pozzer, Andrea

    2016-04-01

    Aromatic hydrocarbons are a subgroup of Volatile Organic Compounds (VOCs) of special interest in the atmosphere of urban and semi-urban areas. Aromatics form a high fraction of VOCs, are highly reactive and upon oxidation they are an important source of ozone. These group of VOCs are released to the atmosphere by processes related to biomass burning and fossil fuel consumption, while they are removed from the atmosphere primarily by OH reaction and by dry deposition. In addition, a branch of aromatics (ortho-nitrophenols) produce HONO upon photolysis, which is responsible of certain amount of the OH recycling. Despite their importance in the atmosphere in anthropogenic polluted areas, the influence of aromatics in the ozone production remains largely unknown. This is of particular relevance, being ozone a pollutant with severe side effects on air quality, health and climate. In this work the atmospheric impacts at global scale of the most emitted aromatic VOCs in the gas phase (benzene, toluene, xylenes, ethylbenzene, styrene, phenol, benzaldehyde and trimethylbenzenes) are analysed and assessed. Specifically, the impact on ozone due to aromatic oxidation is estimated, as this is of great interest in large urban areas and can be helpful for developing air pollution control strategies. Further targets are the quantification of the NOx loss and the OH recycling due to aromatic oxidation. In order to investigate these processes, two simulations were performed with the numerical chemistry and climate simulation ECHAM/MESSy Atmospheric Chemistry (EMAC) model. The simulations compare two cases, one with ozone concentrations when aromatics are present or the second one when they are missing. Finally, model simulated ozone is compared against a global set of observations in order to better constrain the model accuracy.

  6. Native Fluorescence Detection Methods, Devices, and Systems for Organic Compounds

    NASA Technical Reports Server (NTRS)

    Hug, William F. (Inventor); Bhartia, Rohit (Inventor); Reid, Ray D. (Inventor); Lane, Arthur L. (Inventor)

    2016-01-01

    Naphthalene, benzene, toluene, xylene, and other volatile organic compounds VOCs have been identified as serious health hazards. Embodiments of the invention are directed to methods and apparatus for near-real-time in-situ detection and accumulated dose measurement of exposure to naphthalene vapor and other hazardous gaseous VOCs. The methods and apparatus employ excitation of fluorophors native or endogenous to compounds of interest using light sources emitting in the ultraviolet below 300 nm and measurement of native fluorescence emissions in distinct wavebands above the excitation wavelength. The apparatus of some embodiments are cell-phone-sized sensor/dosimeter "badges" to be worn by personnel potentially exposed to hazardous VOCs. The badge sensor of some embodiments provides both real time detection and data logging of exposure to naphthalene or other VOCs of interest from which both instantaneous and accumulated dose can be determined.

  7. Duration of emission of volatile organic compounds from mechanically damaged plant leaves.

    PubMed

    Smith, Lincoln; Beck, John J

    2015-09-01

    Classical biological control of invasive alien weeds depends on the use of arthropod herbivores that are sufficiently host specific to avoid risk of injuring nontarget plants. Host plant specificity is usually evaluated by using a combination of behavioral and developmental experiments under choice, no-choice and field conditions. Secondary plant compounds are likely to have an important influence on host plant specificity. However, relatively little is known about the volatile organic compounds (VOCs) that are emitted by target and nontarget plants, and how environmental conditions may affect their emission. Previous studies have shown that mechanical damage of leaves increases the composition and content of VOCs emitted. In this study we measured the VOC emissions of five species of plants in the subtribe Centaureinae (Asteraceae)--Carthamus tinctorius, Centaurea cineraria, Centaurea melitensis, Centaurea rothrockii, and Centaurea solstitialis--that have previously been used in host specificity experiments for a prospective biological control agent of yellow starthistle (C. solstitialis). Leaves of each plant were punctured with a needle and the VOCs were collected by solid-phase microextraction (SPME) periodically over 48 h and analyzed by GC-MS. A total of 49 compounds were detected. Damage caused an immediate increase of 200-600% in the composition of VOCs emitted from each plant species, and the amounts generally remained high for at least 48 h. The results indicate that a very unspecific mechanical damage can cause a prolonged change in the VOC profile of plants. Published by Elsevier GmbH.

  8. The VOC-Ozone connection: a grassland case study

    NASA Astrophysics Data System (ADS)

    Wohlfahrt, G.; Hoertnagl, L.; Bamberger, I.; Schnitzhofer, R.; Dunkel, J.; Hammerle, A.; Graus, M.; Hansel, A.

    2009-04-01

    Trophospheric ozone (O3) is formed in the presence of sunlight through the interaction of volatile organic compounds (VOCs) and NOx (NO, NO2). O3 damages plants in several ways, most importantly by reducing net photosynthesis and growth. The extent of this damage depends on the time-integrated absorbed O3 flux (i.e. the dose), which is a function of leaf stomatal conductance and ambient O3 concentration, and further influenced by plant species specific defence mechanisms. VOCs are produced by plants through a variety of pathways and in response to a large number of different driving forces. A large variety of VOCs are emitted by plants in response to stress conditions, including the foliar uptake of O3. Here we present preliminary data from an ongoing study where concurrent measurements of the fluxes of VOCs and O3 are made above a managed mountain grassland in Tyrol/Austria. Fluxes of several different VOCs and O3 are measured by means of the eddy covariance method and a proton transfer reaction mass spectrometer (PTR-MS) and an ozone analyser, respectively. Our findings show that the Methanol (MeOH) flux is correlated with the daily time-integrated O3 uptake by vegetation (integrated daily from sunrise - a surrogate for the O3 dose absorbed and the oxidative stress experienced by plants) - MeOH deposition and emission prevailing at low and high time-integrated O3 uptake rates, respectively. Fluxes of other VOCs were not related to the time-integrated O3 uptake. Integrated over longer time scales (several weeks) no correlation between the O3 uptake and MeOH emissions were found. Our study thus confirms earlier leaf-level studies, who found that MeOH emission increase with O3 dose, at the ecosystems scale. As the reaction with the hydroxyl radical (OH), which is responsible for the destruction of the greenhouse gas methane (CH4), is the major sink of atmospheric MeOH, this process provides a potentially important indirect radiative forcing.

  9. Characterization and control of organic compounds emitted from air pollution sources. Final report

    SciTech Connect

    Schauer, J.J.; Kleeman, M.J.; Cass, G.R.; Simoneit, B.R.T.

    1998-04-01

    A dilution source sampling system is used to quantify the air pollutant emissions from major urban air pollution sources. The emissions from catalyst-equipped gasoline powered-motor vehicles, noncatalyst gasoline-powered motor vehicls, diesel trucks, meat charbroiling, the cooking of vegetables with seed oils, fireplace combustion of softwood and hardwood, cigarette combustion, and paint spray coating operations are characterized. Semi-volatile and particle-phase organic compounds in the diluted source emissions are collected simultaneously by both a traditional filter/PUF (polyurethane foam) sampling train and by an advanced organic compound-based denuder/filter/PUF sampling train to provide information on the gas/particle phase distribution of the semi-volatile organic compounds. Emission rates of hundreds of organic compounds, spanning carbon number from C1 to C29 are determined by gas chromatography/mass spectrometry and gas chromatography with flame ionization detection. Fine partile mass emission rates and fine particle elemental chemical composition are measured as well.

  10. Measurements of hydrocarbons and reduced sulfur compounds emitted from a wastewater treatment pond

    SciTech Connect

    Tran, G.; Geen, C.; Friel, D.

    1996-12-31

    A flux chamber was deployed on the water surface to monitor the emissions of hydrocarbons and reduced sulfur compounds from a wastewater treatment pond at a refinery site. Air samples were collected in Tedlar bags and analyzed on-site by means of a gas chromatograph/flame ionization detector (GC/FID) for hydrocarbons and a gas chromatograph/flame photometric detector (GC/FPD) for reduced sulfur compounds. The standard deviations of the duplicate samples for hydrocarbons and for reduced sulfur compounds were better than 4% and 11%, respectively. The pond was monitored during the daytime and nighttime, under two different weather conditions where the daytime temperatures were about 22{degrees}C and 14{degrees}C. The results showed that the difference between day and night emissions of hydrocarbons and reduced sulfur compounds were greater during the warm weather compared to those during cool weather. Air samples were also collected with charcoal adsorbent tubes and analyzed by means of a gas chromatograph/mass selective detector (GC/MSD) at the BOVAR Environmental (BE) laboratory to confirm the GC/FID hydrocarbon analyses. There was excellent agreement between hydrocarbons identified by GC/FID and GC/MSD. 10 refs., 3 figs.

  11. Effect of resin content and substrate on the emission of BTEX and carbonyls from low-VOC water-based wall paint.

    PubMed

    Zhao, Ping; Cheng, Yu-Hsiang; Lin, Chi-Chi; Cheng, Yu-Lin

    2016-02-01

    The primary aim of this work is to explore the effect of resin content and the effect of substrate on the emission of benzene, toluene, ethylbenzene, and xylene (BTEX) and carbonyls from low-VOC water-based wall paint. Four low-volatile organic compound (VOC) paints include paints A (20% acrylic), B (30% acrylic), C (20% polyvinyl acetate), and D (30% polyvinyl acetate) were painted on stainless steel specimen for the study of resin effect. Green calcium silicate, green cement, and stainless steel were painted with paints A and C for the study of substrate effect. Concentrations of the VOCs in the chamber decreased with the elapsed time. Both resin type and resin quantity in paint had effects on VOC emissions. Paints with acrylic resin emitted less BTEX and carbonyls than paints with polyvinyl acetate resin. However, the effects of resin quantity varied with VOCs. Porous substrates were observed to interact more strongly with paints than inert substrates. Both green calcium silicate and green cement substrates have strong power of adsorption of VOCs from wall paints, namely toluene, formaldehyde, acetaldehyde, 2-butanone, methacrolein, butyraldehyde, and benzaldehyde. Some compounds like toluene, formaldehyde, and butyaldehyde were desorbed very slowly from green calcium silicate and green cement substrates.

  12. Impact of multisource VOC emission on in-vehicle air quality: test chamber simulation

    NASA Astrophysics Data System (ADS)

    Brodzik, K.; Faber, J.; Goƚda-Kopek, A.; Łomankiewicz, D.

    2016-09-01

    Air quality inside vehicle may be strongly influenced by the presence of volatile organic compounds (VOC). The sources of these compounds may be different. In case of new vehicles VOC mainly originate from off-gassing of interior materials, while in used cars exterior pollution, like exhaust gases, starts to dominate. The aim of this work was to check the influence of multiple VOC sources on concentration of volatile organic compounds emitted from car interior parts. For this purpose material emission tests were performed in 1 m3 emission testing chamber (WKE 1000, Weiss, Germany) at 65 °C, 5% RH and with air exchange. Three different car parts were studied: sun visor, headlining, and handbrake lever cover. It was stated that volatile organic compounds concentration inside test chamber during the test performed with three different parts inside was significantly lower than those being result of addition of the results obtained for parts tested separately. Presented results indicate interactions between different materials and their emissions as well as prove that some of materials acts like sorbents.

  13. The role of local environment on the electronic properties of a novel blue-emitting donor-acceptor compound

    NASA Astrophysics Data System (ADS)

    Legaspi, Christian M.; Stubbs, Regan E.; Yaron, David J.; Peteanu, Linda A.; Kemboi, Abraham; Picker, Jesse; Fossum, Eric

    2016-09-01

    With the rising popularity of organic light-emitting diodes (OLEDs) in display applications, demand for more efficient blue emitters has increased. We have recently synthesized a novel blue-emitting, donor-acceptor system employing carbazole as the donor and a benzothiazole derivative as the acceptor, BTZ-CBZ. We find that the solution-phase emission of BTZ-CBZ is highly dependent on solvent polarity, both in lineshape and emission maximum, showing a Stokes shift of 50 nm in methylcyclohexane and 150 nm in acetonitrile. This is expected behavior for donor-acceptor compounds due to the presence of a charge-transfer excited state. However, the solid state properties are more important for OLED devices. Using time-dependent density functional theory calculations employing the linear-response (LR) and state-specific (SS) polarizable continuum model (PCM), we explore the effects of solvent reorganization on the emission properties of BTZ-CBZ. SS-PCM reproduces the solvatochromism behavior of BTZ-CBZ in solution, but LR-PCM shows effectively no shift with solvent polarity. We surmise that this is because solvent reorganization is necessary for the solvatochromic effect to occur. The effect of rigid matrices on the emission of BTZ-CBZ has direct implications on its viability as a blue emitter in solid-state OLEDs and which molecular environments will be ideal for devices.

  14. Characteristics of carbonaceous aerosols emitted from peatland fire in Riau, Sumatra, Indonesia (2): Identification of organic compounds

    NASA Astrophysics Data System (ADS)

    Fujii, Yusuke; Kawamoto, Haruo; Tohno, Susumu; Oda, Masafumi; Iriana, Windy; Lestari, Puji

    2015-06-01

    Smoke emitted from Indonesian peatland fires has caused dense haze and serious air pollution in Southeast Asia such as visibility impairment and adverse health impacts. To mitigate the Indonesian peatland fire aerosol impacts, an effective strategy and international framework based on the latest scientific knowledge needs to be established. Although several attempts have been made, limited data exist regarding the chemical characteristics of peatland fire smoke for the source apportionment. In order to identify the key organic compounds of peatland fire aerosols, we conducted intensive field studies based on ground-based and source-dominated sampling of PM2.5 in Riau Province, Sumatra, Indonesia, during the peatland fire seasons in 2012. Levoglucosan was the most abundant compound among the quantified organic compounds at 8.98 ± 2.28% of the PM2.5 mass, followed by palmitic acid at 0.782 ± 0.163% and mannosan at 0.607 ± 0.0861%. Potassium ion was not appropriate for an indicator of Indonesian peatland fires due to extremely low concentrations associated with smoldering fire at low temperatures. The vanillic/syringic acids ratio was 1.06 ± 0.155 in this study and this may be a useful signature profile for peatland fire emissions. Particulate n-alkanes also have potential for markers to identify impact of Indonesian peatland fire source at a receptor site.

  15. Emission of volatile organic compounds from silage: Compounds, sources, and implications

    NASA Astrophysics Data System (ADS)

    Hafner, Sasha D.; Howard, Cody; Muck, Richard E.; Franco, Roberta B.; Montes, Felipe; Green, Peter G.; Mitloehner, Frank; Trabue, Steven L.; Rotz, C. Alan

    2013-10-01

    Silage, fermented cattle feed, has recently been identified as a significant source of volatile organic compounds (VOCs) to the atmosphere. A small number of studies have measured VOC emission from silage, but not enough is known about the processes involved to accurately quantify emission rates and identify practices that could reduce emissions. Through a literature review, we have focused on identifying the most important compounds emitted from corn silage (the most common type of silage in the US) and the sources of these compounds by quantifying their production and emission potential in silage and describing production pathways. We reviewed measurements of VOC emission from silage and assessed the importance of individual silage VOCs through a quantitative analysis of VOC concentrations within silage. Measurements of VOC emission from silage and VOCs present within silage indicated that alcohols generally make the largest contribution to emission from corn silage, in terms of mass emitted and potential ozone formation. Ethanol is the dominant alcohol in corn silage; excluding acids, it makes up more than half of the mean mass of VOCs present. Acids, primarily acetic acid, may be important when emission is high and all VOCs are nearly depleted by emission. Aldehydes and esters, which are more volatile than acids and alcohols, are important when exposure is short, limiting emission of more abundant but less volatile compounds. Variability in silage VOC concentrations is very high; for most alcohols and acids, tolerance intervals indicate that 25% of silages have concentrations a factor of two away from median values, and possibly much further. This observation suggests that management practices can significantly influence VOC concentrations. Variability also makes prediction of emissions difficult. The most important acids, alcohols, and aldehydes present in silage are probably produced by bacteria (and, in the case of ethanol, yeasts) during fermentation and

  16. Comparison of the substrate effect on VOC emissions from water based varnish and latex paint.

    PubMed

    Silva, Gabriela V; Vasconcelos, M Teresa S D; Santos, Armando M; Fernandes, Eduardo O

    2003-01-01

    analysed using thermal desorption online with gas chromatography provided with both mass selective detection and flame ionisation detection. A double exponential model was applied to the VOC concentrations as a function of time to facilitate the interpretation of the results. The varnish, which was introduced in the test chamber 23 h after the application of the last layer of material, emitted mainly glycolethers. Only primary VOCs were emitted, but their concentrations varied markedly with the nature of the substrate. The higher VOC concentrations were observed for the parquets of cork and eucalyptus, which indicated that they have a much higher porosity and, therefore, a higher power of VOC adsorption than the finished pine parquet (and polyester film). The paint was introduced in the chamber just after its application. Only primary VOCs were emitted (esters, phthalates, glycolethers and white spirit) but some compounds, like 2-(2-butoxyethoxy)ethanol and diethylphthalate, were only observed for paint/polyester, which suggested that they were irreversibly adsorbed by the paint/concrete. Compared with the inert substrate, the rate of VOC emissions was lower for concrete in the wet-stage (first hours after the paint application) but slightly higher later (dry-stage) as a consequence of desorption. As to varnish, the substrates without finishing, like cork and eucalyptus parquets, displayed a higher power of adsorption of VOCs than the pine parquet with finishing, probably because they have a higher porosity. As concerns paint, the total masses of VOCs emitted were lower for concrete than for polyester, indicating that concrete reduces the global VOC emissions from the latex paint. Concrete is seen to have a strong power of adsorption of VOCs. Some compounds, namely 2-(2-butoxyethoxy)ethanol, diethylphthalate and TEXANOL (this partially), were either irreversibly adsorbed by the concrete or desorbed very slowly (at undetected levels). A similar behaviour had not been

  17. Rapid production of positron emitting labeled compounds for use in cardiology PET studies

    NASA Astrophysics Data System (ADS)

    Bolomey, Leonard

    1985-05-01

    Large scale clinical application of positron emission tomography requires a variety of short-lived positron emitting radionuclides to be produced in Curie quantities up to 20 times per day. Rapid routine production of these radiopharmaceuticals requires the collaboration of engineers and chemists to achieve production targetry compatible with high beam current (up to 100 μA) and radionuclide production in a chemical form compatible with the rapid radiochemical synthesis. Chemical processing is further complicated by the need to repeat the procedures several times per day and maintain sterility within the shielded area. At our cyclotron facility primary production targets for 11C, 13N, 15O, and 18F (half lives from 2 min to 2 h) are mounted on a vertical gantr that indexes to position the required target on the beam line. Target changes are handled under microprocessor control remotely from the control room such that all valves, cooling, evacuation of target manifold, and testing of interlocks are handled automatically. This system enables us to change targets, energy and particles in less than five minutes. Since the installation of the cyclotron up to fifteen batches of routine radiopharmaceuticals have been produced per day with very low radiation doses to all personnel involved. These radiopharmaceuticals will be used to measure perfusion, metabolism and other biochemical functions in man non invasively with PET.

  18. Thorium and actinium polyphosphonate compounds as bone-seeking alpha particle-emitting agents.

    PubMed

    Henriksen, Gjermund; Bruland, Oyvind S; Larsen, Roy H

    2004-01-01

    The present study explores the use of alpha-particle-emitting, bone-seeking agents as candidates for targeted radiotherapy. Actinium and thorium 1,4,7,10 tetraazacyclododecane N,N',N'',N''' 1,4,7,10-tetra(methylene) phosphonic acid (DOTMP) and thorium-diethylene triamine N,N',N'' penta(methylene) phosphonic acid (DTMP) were prepared and their biodistribution evaluated in conventional Balb/C mice at four hours after injection. All three bone-seeking agents showed a high uptake in bone and a low uptake in soft tissues. Among the soft tissue organs, only kidney had a relatively high uptake. The femur/kidney ratios for 227Th-DTMP, 228-Ac-DOTMP and 227Th-DOTMP were 14.2, 7.6 and 6.0, respectively. A higher liver uptake of 228Ac-DOTMP was seen than for 227Th-DTMP and 227Th-DOTMP. This suggests that some demetallation of the 228Ac-DOTMP complex had occurred. The results indicate that 225Ac-DOTMP, 227Th-DOTMP and 227Th-DTMP have promising properties as potential therapeutic bone-seeking agents.

  19. Diffusion-controlled reference material for VOC emissions testing: proof of concept.

    PubMed

    Cox, S S; Liu, Z; Little, J C; Howard-Reed, C; Nabinger, S J; Persily, A

    2010-10-01

    Because of concerns about indoor air quality, there is growing awareness of the need to reduce the rate at which indoor materials and products emit volatile organic compounds (VOCs). To meet consumer demand for low emitting products, manufacturers are increasingly submitting materials to independent laboratories for emissions testing. However, the same product tested by different laboratories can result in very different emissions profiles because of a general lack of test validation procedures. There is a need for a reference material that can be used as a known emissions source and that will have the same emission rate when tested by different laboratories under the same conditions. A reference material was created by loading toluene into a polymethyl pentene film. A fundamental emissions model was used to predict the toluene emissions profile. Measured VOC emissions profiles using small-chamber emissions tests compared reasonably well to the emissions profile predicted using the emissions model, demonstrating the feasibility of the proposed approach to create a diffusion-controlled reference material. To calibrate emissions test chambers and improve the reproducibility of VOC emission measurements among different laboratories, a reference material has been created using a polymer film loaded with a representative VOC. Initial results show that the film's VOC emission profile measured in a conventional test chamber compares well to predictions based on independently determined material/chemical properties and a fundamental emissions model. The use of such reference materials has the potential to build consensus and confidence in emissions testing as well as 'level the playing field' for product testing laboratories and manufacturers.

  20. Polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs) mitigation in the pyrolysis process of waste tires using CO₂ as a reaction medium.

    PubMed

    Kwon, Eilhann E; Oh, Jeong-Ik; Kim, Ki-Hyun

    2015-09-01

    Our work reported the CO2-assisted mitigation of PAHs and VOCs in the thermo-chemical process (i.e., pyrolysis). To investigate the pyrolysis of used tires to recover energy and chemical products, the experiments were conducted using a laboratory-scale batch-type reactor. In particular, to examine the influence of the CO2 in pyrolysis of a tire, the pyrolytic products including C1-5-hydrocarbons (HCs), volatile organic carbons (VOCs), and polycyclic aromatic hydrocarbons (PAHs) were evaluated qualitatively by gas chromatography (GC) with mass spectroscopy (MS) as well as with a thermal conductivity detector (TCD). The mass balance of the pyrolytic products under various pyrolytic conditions was established on the basis of their weight fractions of the pyrolytic products. Our experimental work experimentally validated that the amount of gaseous pyrolytic products increased when using CO2 as a pyrolysis medium, while substantially altering the production of pyrolytic oil in absolute content (7.3-17.2%) and in relative composition (including PAHs and VOCs). Thus, the co-feeding of CO2 in the pyrolysis process can be considered an environmentally benign and energy efficient process.

  1. Room temperature red emitting carbodiimide compound Ca(CN2):Mn2+

    NASA Astrophysics Data System (ADS)

    Kubus, Mariusz; Castro, Cristina; Enseling, David; Jüstel, Thomas

    2016-09-01

    Carbodiimides are a growing group of compounds, which raised interest as hosts for luminescent materials. Ca(CN2) doped with 5, 10 and 50 mol% Mn2+ was synthesized by a solid-state metathesis reaction at rather low temperature. The unit cell volume of Ca(CN2) decreases with increasing the Mn2+ concentration. The emission spectra of the doped material show an emission band in the red spectral range originating from the 4T1g(4G)-6A1g(6S) transition.

  2. Speciation of volatile organic compounds from poultry production

    NASA Astrophysics Data System (ADS)

    Trabue, Steven; Scoggin, Kenwood; Li, Hong; Burns, Robert; Xin, Hongwei; Hatfield, Jerry

    2010-09-01

    Volatile organic compounds (VOCs) emitted from poultry production are leading source of air quality problems. However, little is known about the speciation and levels of VOCs from poultry production. The objective of this study was the speciation of VOCs from a poultry facility using evacuated canisters and sorbent tubes. Samples were taken during active poultry production cycle and between production cycles. Levels of VOCs were highest in areas with birds and the compounds in those areas had a higher percentage of polar compounds (89%) compared to aliphatic hydrocarbons (2.2%). In areas without birds, levels of VOCs were 1/3 those with birds present and compounds had a higher total percentage of aliphatic hydrocarbons (25%). Of the VOCs quantified in this study, no single sampling method was capable of quantifying more than 55% of compounds and in several sections of the building each sampling method quantified less than 50% of the quantifiable VOCs. Key classes of chemicals quantified using evacuated canisters included both alcohols and ketones, while sorbent tube samples included volatile fatty acids and ketones. The top five compounds made up close to 70% of VOCs and included: 1) acetic acid (830.1 μg m -3); 2) 2,3-butanedione (680.6 μg m -3); 3) methanol (195.8 μg m -3); 4) acetone (104.6 μg m -3); and 5) ethanol (101.9 μg m -3). Location variations for top five compounds averaged 49.5% in each section of the building and averaged 87% for the entire building.

  3. VOCs monitoring system simulation and design

    NASA Astrophysics Data System (ADS)

    Caldararu, Florin; Vasile, Alexandru; Vatra, Cosmin

    2010-11-01

    The designed and simulated system will be used in the tanning industry, for Volatile Organic Compound (VOC) measurements. In this industry, about 90% of the solvent contained in the emulsions evaporates during its application, giving rise to VOC, which are at the same time hazardous atmospheric pollutants and one of the sources of ground level photochemical ozone formation. It results that a monitoring system is necessary in a leather finishing process, in order to detect hazardous VOC concentration and conducting process in order of VOC concentration diminishing. The paper presents the design of a VOC monitoring system, which includes sensors for VOCs and temperature, the conditioning circuitry for these sensors, the suction system of the gas in the hood, the data acquisition and the computing system and graphic interface. The used sensor in the detection system is a semiconductor sensor, produced by Figaro Engineering Inc., characterized by a short response time, high sensitivity at almost all VOC substances. The design of the conditioning circuitry and data acquisition is done in order to compensate the sensor response variation with temperature and to maintain the low response time of the sensor. The temperature compensation is obtained by using a thermistor circuitry, and the compensation is done within the software design. A Mitsubishi PLC is used to receive the output signals of the circuits including the sensor and of the thermistor, respectively. The acquisition and computing system is done using Mitsubishi ALPHA 2 controller and a graphical terminal, GOT 1000.

  4. Evaluation of low-VOC latex paints

    SciTech Connect

    Chang, J.C.S.; Fortmann, R.C.; Roache, N.F.; Lao, H.C.

    1999-01-01

    The paper gives results of an evaluation of four commercially available low-VOC (volatile organic compound) latex paints as substitutes for conventional latex paints by assessing both their emission characteristics and their performance as coatings. Bulk analysis indicated that the VOC contents of all four paints are considerably lower than those of conventional latex paints. Low-VOC emissions were confirmed by small chamber emission tests. However, sigificant emissions of several aldehydes, especially formaldehyde, were detected from two of the paints. ASTM methods were used to evaluate the hiding power, scrubbability, washability, dry to touch, and yellowing index. The results indicated that one of the low-VOC paints tested showed performance equivalent or superior to that of a widely used conventional latex paint used as a control. It was concluded that low-VOC latex paint can be a viable option to replace conventional latex paints for prevention of indoor air pollution. However, paints marketed as low-VOC may still have significant emissions of some individual VOCs, and some may not have performance characteristics matching those of conventional latex paints.

  5. Evaluation of low-VOC latex paints

    SciTech Connect

    Chang, J.C.S.; Fortmann, R.C.; Roache, N.F.; Lao, H.C.

    1999-11-01

    The paper gives results of an evaluation of four commercially available low-VOC (volatile organic compound) latex paints as substitutes for conventional latex paints by assessing both their emission characteristics and their performance as coatings. Bulk analysis indicated that the VOC contents of all four paints are considerably lower than those of conventional latex paints. Low-VOC emissions were confirmed by small chamber emission tests. However, sigificant emissions of several aldehydes, especially formaldehyde, were detected from two of the paints. ASTM methods were used to evaluate the hiding power, scrubbability, washability, dry to touch, and yellowing index. The results indicated that one of the low-VOC paints tested showed performance equivalent or superior to that of a widely used conventional latex paint used as a control. It was concluded that low-VOC latex paint can be a viable option to replace conventional latex paints for prevention of indoor air pollution. However, paints marketed as low-VOC may still have significant emissions of some individual VOCs, and some may not have performance characteristics matching those of conventional latex paints.

  6. VOC Control: Current practices and future trends

    SciTech Connect

    Moretti, E.C.; Mukhopadhyay, N. )

    1993-07-01

    One of the most formidable challenges posed by the Clean Air Act Amendments of 1990 (CAAA) is the search for efficient and economical control strategies for volatile organic compounds (VOCs). VOCs are precursors to ground-level ozone, a major component in the formation of smog. Under the CAAA, thousands of currently unregulated sources will be required to reduce or eliminate VOC emissions. In addition, sources that are currently regulated may seek to evaluate alternative VOC control strategies to meet stricter regulatory requirements such as the maximum achievable control technology (MACT) requirements in Title III of the CAAA. Because of the increasing attention being given to VOC control, the American Institute of Chemical Engineers' (AIChE) Center for Waste Reduction Technologies (CWRT) initiated a study of VOC control technologies and regulatory initiatives. A key objective of the project was to identify and describe existing VOC control technologies and air regulations, as well as emerging technologies and forthcoming regulations. That work is the basis for this article.

  7. Effects of volatile compounds emitted by Protea species (Proteaceae) on antennal electrophysiological responses and attraction of cetoniine beetles.

    PubMed

    Steenhuisen, Sandy-Lynn; Jürgens, Andreas; Johnson, Steven D

    2013-03-01

    Evolutionary shifts in pollination systems within a plant genus are commonly associated with changes in floral scent, reflecting selection mediated through the sensory systems of various pollinators. The most common cetoniine beetle pollinator of grassland Protea species in South Africa, Atrichelaphinis tigrina, previously has been shown to have a strong preference for the fruity floral scent of these plants over the weak scent of their bird-pollinated congeners. However, it is not known which of the many compounds found in the scent of beetle pollinated Protea species play a role for pollinator attraction. Electroantennograms (EAG) from A. tigrina beetles were recorded in response to 15 compounds emitted by Protea flower heads. EAG responses to all 15 compounds were significantly greater than those to the paraffin solvent in which they were diluted. The greatest responses were observed for aromatics (anisole, methyl benzoate, methyl salicylate, benzaldehyde) followed by the monoterpene β-linalool, which can comprise up to 66 % of fruity Protea scents. Five compounds that elicited EAG responses (benzaldehyde, β-linalool, (E/Z)-linalool oxide (furanoid), methyl benzoate, and methyl salicylate) were tested in commercially available yellow bucket traps in the field to test their attractiveness to beetles. Traps baited with methyl benzoate, β-linalool, (E/Z)-linalool oxide (furanoid), and methyl salicylate caught significantly more insects than did those containing paraffin only. Methyl benzoate also was more specifically attractive to A. tigrina than was (E/Z)-linalool oxide (furanoid) and paraffin baited controls. A second field experiment using a combination of linalool vs. paraffin baited yellow or green traps showed that trap color had a significant effect on the number of trapped beetles. Yellow traps yielded a ten-fold higher number of insect catches than did green traps. However, the combination of yellow color and the scent compound linalool yielded the

  8. Low VOC Barrier Coating for Industrial Maintenance

    DTIC Science & Technology

    2012-09-01

    surface area VOC volatile organic compound UFGS Unified Facilities Guide Specification USEPA U.S. Environmental Protection Agency UST...many excellent properties include rapid curing at normal temperatures, good adhesion to most surfaces , toughness and chemical resistance to most...resin compounds are widely used in construction, marine, electrical and industrial markets. However, to meet the different physical properties

  9. Lower operating temperatures oxidize VOCs

    SciTech Connect

    Chen, J.

    1996-12-01

    Regenerative catalytic oxidation (RCO) is a new volatile organic compound (VOC) abatement technology that is gaining acceptance in plants where energy costs are high and hours of operation are long. By combining the features of thermal and catalytic oxidation, RCO technology provides an efficient and cost-effective solution to air pollution problems in a variety of industries where hours of operation reach 4,000 annually, and the challenge is growing to reduce energy and operating costs, yet comply with increasingly stringent VOC control regulations. These may include: printed circuit board fabrication (laminate manufacturing), printing (lithography and flexography), coating (cans, coils and fabrics), forest products (production of woods ranging from plywood to medium- and high-density fiberboard) and automotive OEM (spray-paint booths) and component manufacturing (parts spray-painting, resin components, adhesive components, miscellaneous metalworking applications).

  10. Particulate organic compounds emitted from experimental wildland fires in a Mediterranean ecosystem

    NASA Astrophysics Data System (ADS)

    Alves, C. A.; Gonçalves, C.; Evtyugina, M.; Pio, C. A.; Mirante, F.; Puxbaum, H.

    2010-07-01

    Fine (PM 2.5) and coarse (PM 2.5-10) smoke particles from controlled biomass burnings of a shrub-dominated forest in Lousã Mountain, Portugal, enabled the quantification by chromatographic techniques of several molecular tracers for the combustion of Mediterranean forest ecosystems, which could be conducive to source apportionment studies. The major organic components in the smoke samples were pyrolysates of vegetation cuticles, mainly comprising steradienes and sterol derivatives, carbohydrates from the breakdown of cellulose, aliphatic lipids from vegetation waxes and methoxyphenols from the lignin thermal degradation. Most of these compounds are chiefly found in fine particles. Polycyclic aromatic hydrocarbons (PAH) were also present as minor constituents. Anhydrosugar and PAH molecular diagnostic ratios were applied as source assignment tools. Some biomarkers are reported for the first time in biomass burning smoke.

  11. Photocatalytic solar tower reactor for the elimination of a low concentration of VOCs.

    PubMed

    Negishi, Nobuaki; Sano, Taizo

    2014-10-15

    We developed a photocatalytic solar tower reactor for the elimination of low concentrations of volatile organic compounds (VOCs) typically emitted from small industrial establishments. The photocatalytic system can be installed in a narrow space, as the reactor is cylindrical-shaped. The photocatalytic reactor was placed vertically in the center of a cylindrical scattering mirror, and this vertical reactor was irradiated with scattered sunlight generated by the scattering mirror. About 5 ppm toluene vapor, used as representative VOC, was continuously photodegraded and converted to CO2 almost stoichiometrically under sunny conditions. Toluene removal depended only on the intensity of sunlight. The performance of the solar tower reactor did not decrease with half a year of operation, and the average toluene removal was 36% within this period.

  12. Mechanisms of Increased Particle and VOC Emissions during DPF Active Regeneration and Practical Emissions Considering Regeneration.

    PubMed

    Yamada, Hiroyuki; Inomata, Satoshi; Tanimoto, Hiroshi

    2017-03-07

    Mechanisms involved in increased particle and volatile organic compound (VOC) emissions during active and parked active regenerations of a diesel particulate filter (DPF) were investigated using heavy-duty trucks equipped with both a urea selective catalytic reduction system and a DPF (SCR + DPF) and a DPF-only. Particle emissions increased in the later part of the regeneration period but the mechanisms were different above and below 23 nm. Particles above 23 nm were emitted due to the lower filtering efficiency of the DPF because of the decreasing amount of soot trapped during regeneration. Small particles below 23 nm were thought to be mainly sulfuric acid particles produced from SO2 trapped by the catalyst, being released and oxidized during regeneration. Contrary to the particle emissions, VOCs increased in the earlier part of the regeneration period. The mean molecular weights of the VOCs increased gradually as the regeneration proceeded. To evaluate "practical emissions" in which increased emissions during the regeneration were considered, a Regeneration Correction Factor (RCF), which is the average emission during one cycle of regeneration/emission in normal operation, was adopted. The RCFs of PM and VOCs were 1.1-1.5, and those of PNs were as high as 3-140, although they were estimated from a limited number of observations.

  13. Multi-pass gas cell designed for VOCs analysis by infrared spectroscopy system

    NASA Astrophysics Data System (ADS)

    Wang, Junbo; Wang, Xin; Wei, Haoyun

    2015-10-01

    Volatile Organic Compounds (VOCs) emitted from chemical, petrochemical, and other industries are the most common air pollutants leading to various environmental hazards. Regulations to control the VOCs emissions have been more and more important in China, which requires specific VOCs measurement systems to take measures. Multi-components analysis system, with an infrared spectrometer, a gas handling module and a multi-pass gas cell, is one of the most effective air pollution monitoring facilities. In the VOCs analysis system, the optical multi-pass cell is required to heat to higher than 150 degree Celsius to prevent the condensation of the component gas. Besides that, the gas cell needs to be designed to have an optical path length that matches the detection sensitivity requirement with a compact geometry. In this article, a multi-pass White cell was designed for the high temperature absorption measurements in a specified geometry requirement. The Aberration theory is used to establish the model to accurately calculate the astigmatism for the reflector system. In consideration of getting the optimum output energy, the dimensions of cell geometry, object mirrors and field mirror are optimized by the ray-tracing visible simulation. Then finite element analysis was used to calculate the thermal analysis for the structure of the external and internal elements for high stability. According to the simulation, the cell designed in this paper has an optical path length of 10 meters with an internal volume of 3 liters, and has good stability between room temperature to 227 degree Celsius.

  14. Final disposal of VOCs from industrial wastewaters

    SciTech Connect

    Ying, W.; Bonk, R.R.; Hannam, S.C. ); Qi-dong Li )

    1994-08-01

    Vapor phase carbon adsorption followed by spent carbon regeneration and catalytic oxidation were evaluated as methods for disposal of volatile organic compounds (VOCs) released from industrial wastewaters during treatment operations such as aeration, air-stripping and aerobic biodegradation. Adsorptive capacities and breakthrough characteristics for eight VOCs found in many hazardous landfill leachates and contaminated groundwater were compared for selection of the best adsorbent and optimum treatment conditions. Coconut shell-based activated carbons exhibited higher VOC loading capacities than coal-based carbons, fiber carbon, molecular sieve and zeolite. Steam and hot nitrogen were both effective for regeneration of the spent carbon. A small quantity of adsorbates left in the regenerated carbon did not result in immediate VOC breakthrough in the next cycle adsorption treatment. Catalytic oxidation was found to be an attractive alternative for VOC disposal. Using a new commercial catalyst developed for destruction of halogenated organic compounds, even stable VOCs such as trichloroethylene and tetrachloroethylene were completely destroyed at <350[degrees]C when oxidation was conducted at a space velocity of 17000/hr. 25 refs., 10 figs., 10 tabs.

  15. Hot stuff controls for VOC emissions

    SciTech Connect

    Yewshenko, P.

    1995-12-01

    For close to three decades, American industry has paved the way and led the world in controlling volatile organic compound (VOC) emissions. As more and more systems have been installed, the history of operation for the various types of systems has broadened dramatically, spurring significant technological advances, the traditional technologies and those on the cutting edge of VOC control. With the number of technologies available, the environmental professional may have a difficult task choosing the most strategic environmental solution. The conventional, traditional or proven methodology for VOC control has been incineration. Other technologies have been used for very specific applications. In deciding the specific type of incineration system to select, the environmental professional will look at a broad spectrum of evaluation factors. These include initial system cost, operational cost, maintenance requirements, reliability factors and most importantly, the projected success of achieving 99% VOC destruction efficiency. This article provides an overview of the basic differences among incineration technologies.

  16. Locating industrial VOC sources with aircraft observations.

    PubMed

    Toscano, P; Gioli, B; Dugheri, S; Salvini, A; Matese, A; Bonacchi, A; Zaldei, A; Cupelli, V; Miglietta, F

    2011-05-01

    Observation and characterization of environmental pollution, focussing on Volatile Organic Compounds (VOCs), in a high-risk industrial area, are particularly important in order to provide indications on a safe level of exposure, indicate eventual priorities and advise on policy interventions. The aim of this study is to use the Solid Phase Micro Extraction (SPME) method to measure VOCs, directly coupled with atmospheric measurements taken on a small aircraft environmental platform, to evaluate and locate the presence of VOC emission sources in the Marghera industrial area. Lab analysis of collected SPME fibres and subsequent analysis of mass spectrum and chromatograms in Scan Mode allowed the detection of a wide range of VOCs. The combination of this information during the monitoring campaign allowed a model (Gaussian Plume) to be implemented that estimates the localization of emission sources on the ground.

  17. Deposition of terpenes to vegetation - a paradigm shift towards bidirectional VOC exchange?

    NASA Astrophysics Data System (ADS)

    Bamberger, I.; Hörtnagl, L.; Ruuskanen, T.; Schnitzhofer, R.; Müller, M.; Graus, M.; Karl, T.; Wohlfahrt, G.; Hansel, A.

    2012-04-01

    Biogenic volatile organic compounds (BVOCs) are important precursors for secondary organic aerosol (SOA) formation (Hallquist et al., 2009). In addition reactive BVOCs play a crucial role in local tropospheric ozone production (Atkinson, 2000). According to the present scientific understanding vegetation is recognized as a major VOC emission source rather than a deposition sink. Our recent observations however demonstrate that an uptake of terpene compounds to mountain grassland can be significant - at least under certain atmospheric conditions. After a severe hailstorm volume mixing ratios (VMR) of locally emitted terpene compounds originating from conifers located at the mountain slopes were strongly enhanced, even during daytime hours. Weeks after the hailstorm our PTR-MS and PTR-time-of-flight (PTR-TOF) instruments still measured deposition fluxes of monoterpenes (m/z 137.133), sesquiterpenes (m/z 205.195), and oxygenated terpenes (m/z 153.128) to the grassland. The total amount of terpenoids (on a carbon basis) deposited to the grassland during the weeks after the hailstorm is comparable to the total methanol emission of the entire growing season (Bamberger et al., 2011). These findings pose the question whether the terminology should be adjusted from VOC emission to VOC exchange.

  18. Evaluations of an Enhanced Total Hydrocarbon Analyzer With Complex Mixtures of Volatile Organic Compounds

    NASA Technical Reports Server (NTRS)

    Cross, John H.; Limero, Thomas F.; James, John T.; Breach, James; Hinton, Mark

    1995-01-01

    From the earliest manned missions, the volatile organic compound (VOC) content of spacecraft air has been a concern because of a much greater potential for contamination than air in most terrestrial settings. First, the volume of air is small compared to the mass of man- made materials comprising the interior furnishings of the spacecraft. These man-made materials offgas VOCs trapped during manufacture. Second, the nitrogen fraction of the air is recycled. Any VOCs not scrubbed out with charcoal filters or aqueous condensate (mainly water expired by the crew) will accumulate in the air. Third, the crew emits metabolic VOCs. Fourth, experimental payloads can also offgas or accidentally release a VOC; in fact a major organic constituent of the atmosphere is the disinfectant isopropanol released from swabs used in medical experiments.

  19. Evaluations of an Enhanced Total Hydrocarbon Analyzer With Complex Mixtures of Volatile Organic Compounds

    NASA Technical Reports Server (NTRS)

    Cross, John H.; Limero, Thomas F.; James, John T.; Breach, James; Hinton, Mark

    1995-01-01

    From the earliest manned missions, the volatile organic compound (VOC) content of spacecraft air has been a concern because of a much greater potential for contamination than air in most terrestrial settings. First, the volume of air is small compared to the mass of man- made materials comprising the interior furnishings of the spacecraft. These man-made materials offgas VOCs trapped during manufacture. Second, the nitrogen fraction of the air is recycled. Any VOCs not scrubbed out with charcoal filters or aqueous condensate (mainly water expired by the crew) will accumulate in the air. Third, the crew emits metabolic VOCs. Fourth, experimental payloads can also offgas or accidentally release a VOC; in fact a major organic constituent of the atmosphere is the disinfectant isopropanol released from swabs used in medical experiments.

  20. Characteristics of microbial volatile organic compound flux rates from soil and plant litter

    NASA Astrophysics Data System (ADS)

    Gray, C. M.; Fierer, N.

    2013-12-01

    Our knowledge of microbial production and consumption of volatile organic compounds (VOCs) from soil and litter, as well as which microorganisms are involved, is relatively limited compared to what we know about VOC emissions from terrestrial plants. With climate change expecting to alter plant community composition, nitrogen (N) deposition rates, mean annual temperatures, precipitation patterns, and atmospheric VOC concentrations, it is unknown how microbial production and consumption of VOCs from litter and soil will respond. We have spent the last 5 years quantifying VOC flux rates in decaying plant litter, mineral soils and from a subalpine field site using a proton transfer reaction mass spectrometer (PTR-MS). Microbial production, relative to abiotic sources, accounted for 78% to 99% of the total VOC emissions from decomposing litter, highlighting the importance of microbial metabolisms in these systems. Litter chemistry correlated with the types of VOCs emitted, of which, methanol was emitted at the highest rates from all studies. The net emissions of carbon as VOCs was found to be up to 88% of that emitted as CO2 suggesting that VOCs likely represent an important component of the carbon cycle in many terrestrial systems. Nitrogen additions drastically reduced VOC emissions from litter to near zero, though it is still not understood whether this was due to an increase in consumption or a decrease in production. In the field, the root system contributed to 53% of the carbon that was emitted as VOCs from the soil with increasing air temperatures correlating to an increase in VOC flux rates from the soil system. Finally, we are currently utilizing next generation sequencing techniques (Illumina MiSeq) along with varying concentrations of isoprene, the third most abundant VOC in the atmosphere behind methane and methanol, above soils in a laboratory incubation to determine consumption rates and the microorganisms (bacteria, archaea and fungi) associated with the

  1. Study of the VOC emissions from a municipal solid waste storage pilot-scale cell: comparison with biogases from municipal waste landfill site.

    PubMed

    Chiriac, R; De Araujos Morais, J; Carre, J; Bayard, R; Chovelon, J M; Gourdon, R

    2011-11-01

    The emission of volatile organic compounds (VOCs) from municipal solid waste stored in a pilot-scale cell containing 6.4 tonnes of waste (storage facility which is left open during the first period (40 days) and then closed with recirculation of leachates during a second period (100 days)) was followed by dynamic sampling on activated carbon and analysed by GC-MS after solvent extraction. This was done in order to know the VOC emissions before the installation of a methanogenesis process for the entire waste mass. The results, expressed in reference to toluene, were exploited during the whole study on all the analyzable VOCs: alcohols, ketones and esters, alkanes, benzenic and cyclic compounds, chlorinated compounds, terpene, and organic sulphides. The results of this study on the pilot-scale cell are then compared with those concerning three biogases from a municipal waste landfill: biogas (1) coming from waste cells being filled or recently closed, biogas (2) from all the waste storage cells on site, and biogas (3) which is a residual gas from old storage cells without aspiration of the gas. The analysis of the results obtained revealed: (i) a high emission of VOCs, principally alcohols, ketones and esters during the acidogenesis; (ii) a decrease in the alkane content and an increase in the terpene content were observed in the VOCs emitted during the production of methane; (iii) the production of heavier alkanes and an increase in the average number of carbon atoms per molecule of alkane with the progression of the stabilisation/maturation process were also observed. Previous studies have concentrated almost on the analysis of biogases from landfills. Our research aimed at gaining a more complete understanding of the decomposition/degradation of municipal solid waste by measuring the VOCs emitted from the very start of the landfill process i.e. during the acidogenesis and acetogenesis phases.

  2. TREATMENT OF VOCS IN HIGH STRENGTH WASTES USING AN ANAEROBIC EXPANDED-BED GAS REACTOR

    EPA Science Inventory

    The potential of the expanded-bed granular activated carbon (GAC) anaerobic reactor in treating a high strength waste containing RCRA volatile organic compounds (VOCs) was studied. A total of six VOCs, methylene chloride, chlorobenzene, carbon tetrachloride, chloroform, toluene ...

  3. TREATMENT OF VOCS IN HIGH STRENGTH WASTES USING AN ANAEROBIC EXPANDED-BED GAS REACTOR

    EPA Science Inventory

    The potential of the expanded-bed granular activated carbon (GAC) anaerobic reactor in treating a high strength waste containing RCRA volatile organic compounds (VOCs) was studied. A total of six VOCs, methylene chloride, chlorobenzene, carbon tetrachloride, chloroform, toluene ...

  4. Volatile organic compounds released from Microcystis flos-aquae under nitrogen sources and their toxic effects on Chlorella vulgaris.

    PubMed

    Xu, Qinghuan; Yang, Lin; Yang, Wangting; Bai, Yan; Hou, Ping; Zhao, Jingxian; Zhou, Lv; Zuo, Zhaojiang

    2017-01-01

    Eutrophication promotes massive growth of cyanobacteria and algal blooms, which can poison other algae and reduce biodiversity. To investigate the differences in multiple nitrogen (N) sources in eutrophicated water on the emission of volatile organic compounds (VOCs) from cyanobacteria, and their toxic effects on other algal growth, we analyzed VOCs emitted from Microcystis flos-aquae with different types and concentrations of nitrogen, and determined the effects under Normal-N and Non-N conditions on Chlorella vulgaris. M. flos-aquae released 27, 22, 20, 27, 19, 25 and 17 compounds, respectively, with NaNO3, NaNO2, NH4Cl, urea, Ser, Lys and Arg as the sole N source. With the reduction in N amount, the emission of VOCs was increased markedly, and the most VOCs were found under Non-N condition. C. vulgaris cell propagation, photosynthetic pigment and Fv/Fm declined significantly following exposure to M. flos-aquae VOCs under Non-N condition, but not under Normal-N condition. When C. vulgaris cells were treated with two terpenoids, eucalyptol and limonene, the inhibitory effects were enhanced with increasing concentrations. Therefore, multiple N sources in eutrophicated water induce different VOC emissions from cyanobacteria, and reduction in N can cause nutrient competition, which can result in emissions of more VOCs. Those VOCs released from M. flos-aquae cells under Non-N for nutrient competition can inhibit other algal growth. Among those VOCs, eucalyptol and limonene are the major toxic agents.

  5. Patterns in volatile organic compound emissions along a savanna-rainforest gradient in central Africa

    NASA Astrophysics Data System (ADS)

    Klinger, L. F.; Greenburg, J.; Guenther, A.; Tyndall, G.; Zimmerman, P.; M'bangui, M.; Moutsamboté, J.-M.; Kenfack, D.

    1998-01-01

    In temperate regions the chemistry of the lower troposphere is known to be significantly affected by biogenic volatile organic compounds (VOCs) emitted by plants. The chemistry of the lower troposphere over the tropics, however, is poorly understood, in part because of the considerable uncertainties in VOC emissions from tropical ecosystems. Present global VOC models predict that base emissions of isoprene from tropical rainforests are considerably higher than from savannas. These global models of VOC emissions which rely mainly on species inventories are useful, but significant improvement might be made with more ecologically based models of VOC emissions by plants. Ecosystems along a successional transect from woodland savanna to primary rainforest in central Africa were characterized for species composition and vegetation abundance using ground surveys and remotely sensed data. A total of 336 species (mostly trees) at 13 sites were recorded, and 208 of these were measured for VOC emissions at near-optimal light and temperature conditions using a leaf cuvette and hand-held photoionization detector (PID). A subset of 59 species was also sampled using conventional VOC emission techniques in order to validate the PID technique. Results of ecological and VOC emission surveys indicate both phylogenetic and successional patterns along the savanna-rainforest transect. Genera and families of trees which tend to emit isoprene include Lophira, Irvingia, Albizia, Artocarpus, Ficus, Pterocarpus, Caesalpiniaceae, Arecaceae, and Moraceae. Other taxa tend to contain stored VOCs (Annonaceae and Asteraceae). Successional patterns suggest that isoprene emissions are highest in the relatively early successional Isoberlinia forest communities and progressively decrease in the later successional secondary and primary rainforest communities. Stored VOCs appear to increase along the savanna-rainforest succession, but these data are more tentative. These findings are consistent with

  6. Emissions of volatile organic compounds from new carpets measured in a large-scale environmental chamber

    SciTech Connect

    Hodgson, A.T.; Wooley, J.D.; Daisey, J.M. )

    1993-03-01

    This study was undertaken to quantify the emissions of volatile organic compounds (VOCs) released by new carpets. Samples of four typical carpets, including two with styrene-butadiene rubber (SBR) latex adhesive and two with different backings, were collected from the finish lines at manufacturers' mills. Individual VOCs released from these samples were identified, and their concentrations, emission rates and mass emissions were measured under simulated indoor conditions in a 20 m[sup 3] environmental chamber over one week periods. Concentrations and emission rates of VOCs emitted by a new SBR carpet were also measured in a house. The carpets emitted a variety of VOCs. The two SBR carpets primarily emitted 4-phenylcyclohexene (4-PCH), the source of [open quotes]new carpet[close quotes] odor, and styrene. The concentrations and emission rates of 4-PCH were similar for the two carpets, while the styrene values varied significantly. The carpet with a polyvinyl chloride backing emitted formaldehyde, vinyl acetate, isooctane, 1,2-propanediol, and 2-ethyl-1-hexanol. Of these, vinyl acetate and propanediol had the highest concentrations and emission rates. The carpet with a polyurethane backing primarily emitted butylated hydroxytoluene. With the exception of formaldehyde, little is known about the health effects of these VOCs at low concentrations. 23 refs., 3 figs., 6 tabs.

  7. Emissions of volatile organic compounds from new carpets measured in a large-scale environmental chamber.

    PubMed

    Hodgson, A T; Wooley, J D; Daisey, J M

    1993-03-01

    This study was undertaken to quantify the emissions of volatile organic compounds (VOCs) released by new carpets. Samples of four typical carpets, including two with styrene-butadiene rubber (SBR) latex adhesive and two with different backings, were collected from the finish lines at manufacturers' mills. Individual VOCs released from these samples were identified, and their concentrations, emission rates and mass emissions were measured under simulated indoor conditions in a 20 m3 environmental chamber over one week periods. Concentrations and emission rates of VOCs emitted by a new SBR carpet were also measured in a house. The carpets emitted a variety of VOCs. The two SBR carpets primarily emitted 4-phenylcyclohexene (4-PCH), the source of "new carpet" odor, and styrene. The concentrations and emission rates of 4-PCH were similar for the two carpets, while the styrene values varied significantly. The carpet with a polyvinyl chloride backing emitted formaldehyde, vinyl acetate, isooctane, 1,2-propanediol, and 2-ethyl-1-hexanol. Of these, vinyl acetate and propanediol had the highest concentrations and emission rates. The carpet with a polyurethane backing primarily emitted butylated hydroxytoluene. With the exception of formaldehyde, little is known about the health effects of these VOCs at low concentrations.

  8. VOC and HAP recovery using ionic liquids

    SciTech Connect

    Michael R. Milota : Kaichang Li

    2007-05-29

    During the manufacture of wood composites, paper, and to a lesser extent, lumber, large amounts of volatile organic compounds (VOCs) such as terpenes, formaldehyde, and methanol are emitted to air. Some of these compounds are hazardous air pollutants (HAPs). The air pollutants produced in the forest products industry are difficult to manage because the concentrations are very low. Presently, regenerative thermal oxidizers (RTOs and RCOs) are commonly used for the destruction of VOCs and HAPs. RTOs consume large amounts of natural gas to heat air and moisture. The combustion of natural gas generates increased CO2 and NOx, which have negative implications for global warming and air quality. The aforementioned problems are addressed by an absorption system containing a room-temperature ionic liquid (RTIL) as an absorbent. RTILs are salts, but are in liquid states at room temperature. RTILs, an emerging technology, are receiving much attention as replacements for organic solvents in industrial processes with significant cost and environmental benefits. Some of these processes include organic synthesis, extraction, and metal deposition. RTILs would be excellent absorbents for exhausts from wood products facilities because of their unique properties: no measurable vapor pressure, high solubility of wide range of organic compounds, thermal stability to 200°C (almost 400°F), and immisciblity with water. Room temperature ionic liquids were tested as possible absorbents. Four were imidizolium-based and were eight phosphonium-based. The imidizolium-based ionic liquids proved to be unstable at the conditions tested and in the presence of water. The phosphonium-based ionic liquids were stable. Most were good absorbents; however, cleaning the contaminates from the ionic liquids was problematic. This was overcome with a higher temperature (120°C) than originally proposed and a very low pressure (1 kPa. Absorption trials were conducted with tetradecy

  9. VOC removal and deodorization of effluent gases from an industrial plant by photo-oxidation, chemical oxidation, and ozonization.

    PubMed

    Domeño, Celia; Rodríguez-Lafuente, Angel; Martos, J M; Bilbao, Rafael; Nerín, Cristina

    2010-04-01

    The efficiency of photo-oxidation, chemical oxidation by sodium hypochlorite, and ozonization for the industrial-scale removal of volatile organic compounds (VOCs) and odors from gaseous emissions was studied by applying these treatments (in an experimental system) to substances passing through an emission stack of a factory producing maize derivatives. Absorption and ozonization were the most efficient treatment, removing 75% and 98% of VOCs, respectively, while photo-oxidation only removed about 59%. The emitted chemical compounds and odors were identified and quantified by gas chromatography-mass spectrometry (in full-scan mode). In addition to presenting the results, their implications for selecting optimal processes for treating volatile emissions are discussed.

  10. On-line measurements of nitro organic compounds emitted from automobiles by proton transfer reaction mass spectrometry: Laboratory experiments and a field measurement

    NASA Astrophysics Data System (ADS)

    Inomata, S.; Tanimoto, H.; Fujitani, Y.; Fushimi, A.; Sato, K.; Sekimoto, K.; Yamada, H.; Hori, S.; Shimono, A.; Hikida, T.

    2011-12-01

    On-line measurements of nitro organic compounds in automobile exhaust were carried out by proton transfer reaction mass spectrometry (PTR-MS) with a chassis dynamometer. Diesel vehicles with oxidation catalyst system (diesel vehicle A) and with diesel PM-NOx reduction system ((diesel vehicle B) and a gasoline vehicle were used as a test vehicle. In the case of the diesel vehicle A, the emissions of nitromethane, nitrophenol (NPh), C7-, C8-, C9-, and C10-nitrophenols, and dihydroxynitrobenzenes (DHNB) were observed in the diesel exhaust from the experiment under the constant driving at 60 km hr-1. Temporal variations of mixing ratios for nitromethane, NPh, and DHNB along with related volatile organic compounds (VOCs) were measured during a transient driving cycle. The time-resolved measurement revealed that the nitromethane emission was strongly correlated with the emissions of CO, benzene, and acetone, which are relatively quickly produced in acceleration processes and appeared as sharp peaks. On the other hand, the NPh emission was moderately correlated with the emissions of acetic acid and phenol, which peaks were broad. The emission of nitromethane was observed from the exhaust of the diesel vehicle B but the emission of other nitro organic compounds was not observed. This suggests that the emission of nitro organic compounds besides nitromethane may depend on the diesel exhaust aftertreatment devices. The emission of nitromethane was also observed from the exhaust of the gasoline vehicle with cold start. An in-situ measurement of nitro organic compounds and their related VOCs was carried out at the crossing of an urban city, Kawasaki. Nitromethane was observed at the crossing and we found that the concentration of nitrometane varied rapidly. During the measurement, the maximum of the concentration of nitrometane reached 5 ppbv. Not only nitrophenols but also nitroaromatics were sometimes detected in the field measurement.

  11. A process-based emission model for volatile organic compounds from silage sources on farms

    USDA-ARS?s Scientific Manuscript database

    Silage on dairy farms can emit large amounts of volatile organic compounds (VOCs), a precursor in the formation of tropospheric ozone. Because of the challenges associated with direct measurements, process-based modeling is another approach for estimating emissions of air pollutants from sources suc...

  12. ESTIMATES OF REGIONAL NATURAL VOLATILE ORGANIC COMPOUND FLUXES FROM ENCLOSURE AND AMBIENT MEASUREMENTS

    EPA Science Inventory

    The paper discusses results of an investigation at two forested sites in the Southeastern United States. A variety of VOC compounds including methanol, 2-methyl-3-buten-2-ol, 6-methyl-5-hepten-
    2-one, isoprene, and 15 monoterpenes were emitted from vegetation at these sites. D...

  13. ESTIMATES OF REGIONAL NATURAL VOLATILE ORGANIC COMPOUND FLUXES FROM ENCLOSURE AND AMBIENT MEASUREMENTS

    EPA Science Inventory

    The paper discusses results of an investigation at two forested sites in the Southeastern United States. A variety of VOC compounds including methanol, 2-methyl-3-buten-2-ol, 6-methyl-5-hepten-
    2-one, isoprene, and 15 monoterpenes were emitted from vegetation at these sites. D...

  14. VOCs elimination and health risk reduction in e-waste dismantling workshop using integrated techniques of electrostatic precipitation with advanced oxidation technologies.

    PubMed

    Chen, Jiangyao; Huang, Yong; Li, Guiying; An, Taicheng; Hu, Yunkun; Li, Yunlu

    2016-01-25

    Volatile organic compounds (VOCs) emitted during the electronic waste dismantling process (EWDP) were treated at a pilot scale, using integrated electrostatic precipitation (EP)-advanced oxidation technologies (AOTs, subsequent photocatalysis (PC) and ozonation). Although no obvious alteration was seen in VOC concentration and composition, EP technology removed 47.2% of total suspended particles, greatly reducing the negative effect of particles on subsequent AOTs. After the AOT treatment, average removal efficiencies of 95.7%, 95.4%, 87.4%, and 97.5% were achieved for aromatic hydrocarbons, aliphatic hydrocarbons, halogenated hydrocarbons, as well as nitrogen- and oxygen-containing compounds, respectively, over 60-day treatment period. Furthermore, high elimination capacities were also seen using hybrid technique of PC with ozonation; this was due to the PC unit's high loading rates and excellent pre-treatment abilities, and the ozonation unit's high elimination capacity. In addition, the non-cancer and cancer risks, as well as the occupational exposure cancer risk, for workers exposed to emitted VOCs in workshop were reduced dramatically after the integrated technique treatment. Results demonstrated that the integrated technique led to highly efficient and stable VOC removal from EWDP emissions at a pilot scale. This study points to an efficient approach for atmospheric purification and improving human health in e-waste recycling regions. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. A farm-level model of VOC emission from silage

    USDA-ARS?s Scientific Manuscript database

    Recent measurements suggest that dairy farms can be a significant emission source of volatile organic compounds (VOCs). However, accurate estimates of farm-level emissions currently do not exist. A preliminary process-based model was developed to estimate VOC emissions from silage on farms and to as...

  16. VOC EMISSIONS FROM AN AIR FRESHENER IN THE INDOOR ENVIRONMENT

    EPA Science Inventory

    The paper describes results of tests, conducted in the U.S. Environmental Protection Agency (EPA) large chamber facility, that investigated emissions of volatile organic compounds (VOCS) from one electrical plug-in type air freshener with pine-scented refills. VOCs were measured ...

  17. Unsteady-state VOC transport in vented waste drums

    SciTech Connect

    Liekhus, K.J.; Gresham, G.L.; Peterson, E.S.; Rae, C.; Hotz, N.J.; Connolly, M.J.

    1993-08-01

    A model of unsteady-state volatile organic compound (VOC) transport in a vented waste drum has been developed. Model predictions of the VOC concentration in the innermost layer of confinement and the drum headspace are compared to measurements in lab-scale simulated waste drums.

  18. VOC EMISSIONS FROM AN AIR FRESHENER IN THE INDOOR ENVIRONMENT

    EPA Science Inventory

    The paper describes results of tests, conducted in the U.S. Environmental Protection Agency (EPA) large chamber facility, that investigated emissions of volatile organic compounds (VOCS) from one electrical plug-in type air freshener with pine-scented refills. VOCs were measured ...

  19. Characterization and measurement of VOC emissions from silage

    USDA-ARS?s Scientific Manuscript database

    There is growing concern in the U.S. regarding the emission of volatile organic compounds (VOCs) from farms and their contribution to smog formation near ozone non-attainment areas. The few studies that have measured VOC emissions have identified mixed feed and the exposed silage face as major farm ...

  20. Sources and reactivity of NMHCs and VOCs in the atmosphere: a review.

    PubMed

    Kansal, Ankur

    2009-07-15

    Nonmethane hydrocarbons (NMHCs) and volatile organic compounds (VOCs) are important species present in the environment, which results in alteration of the chemistry of atmosphere. On the global scale natural emissions of NMHCs and VOCs exceed anthropogenic emissions, although anthropogenic sources usually dominate within urban areas. Among the natural sources, vegetation is the dominant source. Oceanic and microbial production of these species is minimal as compared to other sources of input. Isoprene and terpenes are main species of NMHCs which are emitted from plants as a protective mechanism against temperature stress tolerance and protection from ravages of insects and pests. The major anthropogenic sources for NMHCs emissions are biomass burning and transportation. NMHCs play a significant role in ozone (O(3)) production in the presence of adequate concentration of oxides of nitrogen in the atmosphere. The production of O(3) is based on Maximum Incremental Reactivity (MIR) of NMHCS and VOCs. The compound's MIR multiplied by molecular weight gives Relative Ozone Productivity (ROPi). To check the reliability of current methods of measuring the NMHCs the Nonmethane Hydrocarbon Inter-comparison Experiment (NMHICE) had been designed. The sample of known composition and unknown concentration of different hydrocarbons was supplied to different laboratories worldwide and less than 50% laboratories correctly separated the unknown mixture. Atmospheric scientists throughout the world are evaluating current analytical methods being employed and are trying to correct the problems to ensure quality control in hydrocarbon analysis.

  1. VOCs in Arid soils: Technology summary

    SciTech Connect

    Not Available

    1994-02-01

    The Volatile Organic Compounds In Arid Soils Integrated Demonstration (VOC-Arid ID) focuses on technologies to clean up volatile organic compounds and associated contaminants in soil and groundwater at arid sites. The initial host site is the 200 West Area at DOE`s Hanford site in southeastern Washington state. The primary VOC contaminant is carbon tetrachloride, in association with heavy metals and radionuclides. An estimated 580--920 metric tons of carbon tetrachloride were disposed of between 1955 and 1973, resulting in extensive soil and groundwater contamination. The VOC-Arid ID schedule has been divided into three phases of implementation. The phased approach provides for: rapid transfer of technologies to the Environmental Restoration (EM-40) programs once demonstrated; logical progression in the complexity of demonstrations based on improved understanding of the VOC problem; and leveraging of the host site EM-40 activities to reduce the overall cost of the demonstrations. During FY92 and FY93, the primary technology demonstrations within the ID were leveraged with an ongoing expedited response action at the Hanford 200 West Area, which is directed at vapor extraction of VOCs from the vadose (unsaturated) zone. Demonstration efforts are underway in the areas of subsurface characterization including: drilling and access improvements, off-gas and borehole monitoring of vadose zone VOC concentrations to aid in soil vapor extraction performance evaluation, and treatment of VOC-contaminated off-gas. These current demonstration efforts constitute Phase 1 of the ID and, because of the ongoing vadose zone ERA, can result in immediate transfer of successful technologies to EM-40.

  2. Evaluation of the Effect of Two Volatile Organic Compounds on Barley Pathogens.

    PubMed

    Kaddes, Amine; Parisi, Olivier; Berhal, Chadi; Ben Kaab, Sofiene; Fauconnier, Marie-Laure; Nasraoui, Bouzid; Jijakli, M Haissam; Massart, Sébastien; De Clerck, Caroline

    2016-08-26

    This study aimed to determine the effect of Volatile Organic Compounds (VOCs) on some pathogens, these VOCs were emitted during interactions of barley with Fusarium culmorum Schltdl and/or Cochliobolus sativus Shoemaker, two common root rot pathogens. Our work shows that two organic esters: methyl propanoate (MP) and methyl prop-2-enoate (MA) significantly reduced the development of fungi in vitro. Additional tests showed that the esters significantly inhibited spore germination of these pathogens. The activity of these VOCs on a wide range of fungal and bacterial pathogens was also tested in vitro and showed inhibitory action. The effect of the VOCs on infected barley seeds also showed plantlets growing without disease symptoms. MA and MP seem to have potential value as alternative plant protection compounds against barley bioagressors.

  3. Quantification of volatile organic compounds in smoke from prescribed burning and comparison with occupational exposure limits

    NASA Astrophysics Data System (ADS)

    Romagnoli, E.; Barboni, T.; Santoni, P.-A.; Chiaramonti, N.

    2014-05-01

    Prescribed burning represents a serious threat to personnel fighting fires due to smoke inhalation. The aim of this study was to investigate exposure by foresters to smoke from prescribed burning, focusing on exposure to volatile organic compounds (VOCs). The methodology for smoke sampling was first evaluated. Potentially dangerous compounds were identified among the VOCs emitted by smoke fires at four prescribed burning plots located around Corsica. The measured mass concentrations for several toxic VOCs were generally higher than those measured in previous studies due to the experimental framework (short sampling distance between the foresters and the flame, low combustion, wet vegetation). In particular, benzene, phenol and furfural exceeded the legal short-term exposure limits published in Europe and/or the United States. Other VOCs such as toluene, ethybenzene or styrene remained below the exposure limits. In conclusion, clear and necessary recommendations were made for protection of personnel involved in fighting fires.

  4. Effects of heat and drought stress on post‐illumination bursts of volatile organic compounds in isoprene‐emitting and non‐emitting poplar

    PubMed Central

    Jud, Werner; Vanzo, Elisa; Li, Ziru; Ghirardo, Andrea; Zimmer, Ina; Sharkey, Thomas D.; Schnitzler, Jörg‐Peter

    2016-01-01

    Abstract Over the last decades, post‐illumination bursts (PIBs) of isoprene, acetaldehyde and green leaf volatiles (GLVs) following rapid light‐to‐dark transitions have been reported for a variety of different plant species. However, the mechanisms triggering their release still remain unclear. Here we measured PIBs of isoprene‐emitting (IE) and isoprene non‐emitting (NE) grey poplar plants grown under different climate scenarios (ambient control and three scenarios with elevated CO2 concentrations: elevated control, periodic heat and temperature stress, chronic heat and temperature stress, followed by recovery periods). PIBs of isoprene were unaffected by elevated CO2 and heat and drought stress in IE, while they were absent in NE plants. On the other hand, PIBs of acetaldehyde and also GLVs were strongly reduced in stress‐affected plants of all genotypes. After recovery from stress, distinct differences in PIB emissions in both genotypes confirmed different precursor pools for acetaldehyde and GLV emissions. Changes in PIBs of GLVs, almost absent in stressed plants and enhanced after recovery, could be mainly attributed to changes in lipoxygenase activity. Our results indicate that acetaldehyde PIBs, which recovered only partly, derive from a new mechanism in which acetaldehyde is produced from methylerythritol phosphate pathway intermediates, driven by deoxyxylulose phosphate synthase activity. PMID:26390316

  5. Determination and impact of volatile organics emitted during rush hours in the ambient air around gasoline stations.

    PubMed

    Wu, Ben-Zen; Hsieh, Ling-Ling; Sree, Usha; Chiu, Kong-Hwa; Lo, Jiunn-Guang

    2006-09-01

    This study analyzes the volatile organic compounds (VOCs) in the ambient air around gasoline stations during rush hours and assesses their impact on human health. Results from this study clearly indicate that methyl tertiary butyl ether (MTBE), toluene, and isobutane are the major VOCs emitted from gasoline stations. Moreover, the concentrations of MTBE and toluene in the ambient air near gasoline stations are remarkably higher than those sampled on surrounding roads, revealing that these compounds are mainly released from gasoline stations. The concentration of VOCs near the gasoline stations without vapor recovery systems are approximately 7.3 times higher than those around the gasoline stations having the recovery systems. An impact on individual health and air quality because of gasoline station emissions was done using Integrated Risk Information System and Industrial Source Complex Short Term model.

  6. Promotion of plant growth by Pseudomonas fluorescens strain SS101 via novel volatile organic compounds.

    PubMed

    Park, Yong-Soon; Dutta, Swarnalee; Ann, Mina; Raaijmakers, Jos M; Park, Kyungseok

    2015-05-29

    Volatile organic compounds (VOCs) from plant growth-promoting rhizobacteria (PGPR) play key roles in modulating plant growth and induced systemic resistance (ISR) to pathogens. Despite their significance, the physiological functions of the specific VOCs produced by Pseudomonas fluorescens SS101 (Pf.SS101) have not been precisely elucidated. The effects of Pf.SS101 and its VOCs on augmentation of plant growth promotion were investigated in vitro and in planta. A significant growth promotion was observed in plants exposed Pf.SS101 under both conditions, suggesting that its VOCs play a key role in promoting plant growth. Solid-phase micro-extraction (SPME) and a gas chromatography-mass spectrophotometer (GC-MS) system were used to characterize the VOCs emitted by Pf.SS101 and 11 different compounds were detected in samples inoculated this bacterium, including 13-Tetradecadien-1-ol, 2-butanone and 2-Methyl-n-1-tridecene. Application of these compounds resulted in enhanced plant growth. This study suggests that Pf.SS101 promotes the growth of plants via the release of VOCs including 13-Tetradecadien-1-ol, 2-butanone and 2-Methyl-n-1-tridecene, thus increasing understanding of the role of VOCs in plant-bacterial inter-communication.

  7. Analysis of Relative Concentration of Ethanol and Other Odorous Compounds (OCs) Emitted from the Working Surface at a Landfill in China

    PubMed Central

    Li, Dong; Lu, Wenjing; Liu, Yanjun; Guo, Hanwen; Xu, Sai; Ming, Zhongyuan; Wang, Hongtao

    2015-01-01

    Estimating odor emissions from landfill sites is a complicated task because of the various chemical and biological species that exist in landfill gases. In this study, the relative concentration of ethanol and other odorous compounds emitted from the working surface at a landfill in China was analyzed. Gas sampling was conducted at the landfill on a number of selected days from March 2012 to March 2014, which represented different periods throughout the two years. A total of 41, 59, 66, 54, 63, 54, 41, and 42 species of odorous compounds were identified and quantified in eight sampling activities, respectively; a number of 86 species of odorous compounds were identified and quantified all together in the study. The measured odorous compounds were classified into six different categories (Oxygenated compounds, Halogenated compounds, Terpenes, Sulfur compounds, Aromatics, and Hydrocarbons). The total average concentrations of the oxygenated compounds, sulfur compounds, aromatics, halogenated compounds, hydrocarbons, and terpenes were 2.450 mg/m3, 0.246 mg/m3, 0.203 mg/m3, 0.319 mg/m3, 0.530 mg/m3, and 0.217 mg/m3, respectively. The relative concentrations of 59 odorous compounds with respect to the concentration of ethyl alcohol (1000 ppm) were determined. The dominant contaminants that cause odor pollution around the landfill are ethyl sulfide, methyl mercaptan, acetaldehyde, and hydrogen sulfide; dimethyl disulfide and dimethyl sulfide also contribute to the pollution to a certain degree. PMID:25769100

  8. GEIGER BRICKEL BENEFITS FROM LOW -VOC COATINGS

    EPA Science Inventory

    Midwest Research Institute, under a cooperative agreement with the U.S. Environmental Protection Agency (EPA), conducted a study to identify wood furniture manufacturing facilities that had converted to low-volatile organic compound (VOC)/hazardous air pollutant (HAP) wood furnit...

  9. COMPOSITE SAMPLING FOR SOIL VOC ANALYSIS

    EPA Science Inventory

    Data published by numerous researchers over the last decade demonstrate that there is a high degree of spatial variability in the measurement of volatile organic compounds (VOCs) in soil at contaminated waste sites. This phenomenon is confounded by the use of a small sample aliqu...

  10. GEIGER BRICKEL BENEFITS FROM LOW -VOC COATINGS

    EPA Science Inventory

    Midwest Research Institute, under a cooperative agreement with the U.S. Environmental Protection Agency (EPA), conducted a study to identify wood furniture manufacturing facilities that had converted to low-volatile organic compound (VOC)/hazardous air pollutant (HAP) wood furnit...

  11. Contrasting responses of silver birch VOC emissions to short- and long-term herbivory.

    PubMed

    Maja, Mengistu M; Kasurinen, Anne; Yli-Pirilä, Pasi; Joutsensaari, Jorma; Klemola, Tero; Holopainen, Toini; Holopainen, Jarmo K

    2014-03-01

    There is a need to incorporate the effects of herbivore damage into future models of plant volatile organic compound (VOC) emissions at leaf or canopy levels. Short-term (a few seconds to 48 h) changes in shoot VOC emissions of silver birch (Betula pendula Roth) in response to feeding by geometrid moths (Erannis defoliaria Hübner) were monitored online by proton transfer reaction time-of-flight mass spectrometry (PTR-TOF-MS). In addition, two separate field experiments were established to study the effects of long-term foliage herbivory (FH, 30-32 days of feeding by geometrids Agriopis aurantiaria (Clerck) and E. defoliaria in two consecutive years) and bark herbivory (BH, 21 days of feeding by the pine weevil (Hylobius abietis L.) in the first year) on shoot and rhizosphere VOC emissions of three silver birch genotypes (gt14, gt15 and Hausjärvi provenance). Online monitoring of VOCs emitted from foliage damaged by geometrid larvae showed rapid bursts of green leaf volatiles (GLVs) immediately after feeding activity, whereas terpenoid emissions had a tendency to gradually increase during the monitoring period. Long-term FH caused transient increases in total monoterpene (MT) emissions from gt14 and sesquiterpene (SQT) emissions from Hausjärvi provenance, mainly in the last experimental season. In the BH experiment, genotype effects were detected, with gt14 trees having significantly higher total MT emissions compared with other genotypes. Only MTs were detected in the rhizosphere samples of both field experiments, but their emission rates were unaffected by genotype or herbivory. The results suggest that silver birch shows a rapid VOC emission response to short-term foliage herbivory, whereas the response to long-term foliage herbivory and bark herbivory is less pronounced and variable at different time points.

  12. Development and mining of a volatile organic compound database.

    PubMed

    Abdullah, Azian Azamimi; Altaf-Ul-Amin, Md; Ono, Naoaki; Sato, Tetsuo; Sugiura, Tadao; Morita, Aki Hirai; Katsuragi, Tetsuo; Muto, Ai; Nishioka, Takaaki; Kanaya, Shigehiko

    2015-01-01

    Volatile organic compounds (VOCs) are small molecules that exhibit high vapor pressure under ambient conditions and have low boiling points. Although VOCs contribute only a small proportion of the total metabolites produced by living organisms, they play an important role in chemical ecology specifically in the biological interactions between organisms and ecosystems. VOCs are also important in the health care field as they are presently used as a biomarker to detect various human diseases. Information on VOCs is scattered in the literature until now; however, there is still no available database describing VOCs and their biological activities. To attain this purpose, we have developed KNApSAcK Metabolite Ecology Database, which contains the information on the relationships between VOCs and their emitting organisms. The KNApSAcK Metabolite Ecology is also linked with the KNApSAcK Core and KNApSAcK Metabolite Activity Database to provide further information on the metabolites and their biological activities. The VOC database can be accessed online.

  13. Development and Mining of a Volatile Organic Compound Database

    PubMed Central

    Abdullah, Azian Azamimi; Altaf-Ul-Amin, Md.; Ono, Naoaki; Sato, Tetsuo; Sugiura, Tadao; Morita, Aki Hirai; Katsuragi, Tetsuo; Muto, Ai; Nishioka, Takaaki; Kanaya, Shigehiko

    2015-01-01

    Volatile organic compounds (VOCs) are small molecules that exhibit high vapor pressure under ambient conditions and have low boiling points. Although VOCs contribute only a small proportion of the total metabolites produced by living organisms, they play an important role in chemical ecology specifically in the biological interactions between organisms and ecosystems. VOCs are also important in the health care field as they are presently used as a biomarker to detect various human diseases. Information on VOCs is scattered in the literature until now; however, there is still no available database describing VOCs and their biological activities. To attain this purpose, we have developed KNApSAcK Metabolite Ecology Database, which contains the information on the relationships between VOCs and their emitting organisms. The KNApSAcK Metabolite Ecology is also linked with the KNApSAcK Core and KNApSAcK Metabolite Activity Database to provide further information on the metabolites and their biological activities. The VOC database can be accessed online. PMID:26495281

  14. Diagnosing gastrointestinal illnesses using fecal headspace volatile organic compounds

    PubMed Central

    Chan, Daniel K; Leggett, Cadman L; Wang, Kenneth K

    2016-01-01

    Volatile organic compounds (VOCs) emitted from stool are the components of the smell of stool representing the end products of microbial activity and metabolism that can be used to diagnose disease. Despite the abundance of hydrogen, carbon dioxide, and methane that have already been identified in human flatus, the small portion of trace gases making up the VOCs emitted from stool include organic acids, alcohols, esters, heterocyclic compounds, aldehydes, ketones, and alkanes, among others. These are the gases that vary among individuals in sickness and in health, in dietary changes, and in gut microbial activity. Electronic nose devices are analytical and pattern recognition platforms that can utilize mass spectrometry or electrochemical sensors to detect these VOCs in gas samples. When paired with machine-learning and pattern recognition algorithms, this can identify patterns of VOCs, and thus patterns of smell, that can be used to identify disease states. In this review, we provide a clinical background of VOC identification, electronic nose development, and review gastroenterology applications toward diagnosing disease by the volatile headspace analysis of stool. PMID:26819529

  15. Diagnosing gastrointestinal illnesses using fecal headspace volatile organic compounds.

    PubMed

    Chan, Daniel K; Leggett, Cadman L; Wang, Kenneth K

    2016-01-28

    Volatile organic compounds (VOCs) emitted from stool are the components of the smell of stool representing the end products of microbial activity and metabolism that can be used to diagnose disease. Despite the abundance of hydrogen, carbon dioxide, and methane that have already been identified in human flatus, the small portion of trace gases making up the VOCs emitted from stool include organic acids, alcohols, esters, heterocyclic compounds, aldehydes, ketones, and alkanes, among others. These are the gases that vary among individuals in sickness and in health, in dietary changes, and in gut microbial activity. Electronic nose devices are analytical and pattern recognition platforms that can utilize mass spectrometry or electrochemical sensors to detect these VOCs in gas samples. When paired with machine-learning and pattern recognition algorithms, this can identify patterns of VOCs, and thus patterns of smell, that can be used to identify disease states. In this review, we provide a clinical background of VOC identification, electronic nose development, and review gastroenterology applications toward diagnosing disease by the volatile headspace analysis of stool.

  16. Volatile Organic Compounds (VOCs) and Elevated Concentrations of Carbon Dioxide (CO2) in Unsaturated-Zone Vapors Near a Chemical and Low-Level Radioactivity Waste-Disposal Facility, Amargosa Desert Research Site, Nye County, Nevada

    NASA Astrophysics Data System (ADS)

    Baker, R. J.; Andraski, B. J.; Walvoord, M. A.; Stonestrom,