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Sample records for compounds voc emitted

  1. [Volatile organic compounds (VOCs) emitted from furniture and electrical appliances].

    PubMed

    Tanaka-Kagawa, Toshiko; Jinno, Hideto; Furukawa, Yoko; Nishimura, Tetsuji

    2010-01-01

    Organic chemicals are widely used as ingredients in household products. Therefore, furniture and other household products as well as building products may influence the indoor air quality. This study was performed to estimate quantitatively influence of household products on indoor air quality. Volatile organic compound (VOC) emissions were investigated for 10 products including furniture (chest, desk, dining table, sofa, cupboard) and electrical appliances (refrigerator, electric heater, desktop personal computer, liquid crystal display television and audio) by the large chamber test method (JIS A 1912) under the standard conditions of 28 degrees C, 50% relative humidity and 0.5 times/h ventilation. Emission rate of total VOC (TVOC) from the sofa showed the highest; over 7900 microg toluene-equivalent/unit/h. Relatively high TVOC emissions were observed also from desk and chest. Based on the emission rates, the impacts on the indoor TVOC were estimated by the simple model with a volume of 17.4 m3 and ventilation frequency of 0.5 times/h. The estimated TVOC increment for the sofa was 911 microg/m3, accounting for almost 230% of the provisional target value, 400 microg/m3. The values of estimated increment of toluene emitted from cupboard and styrene emitted from refrigerator were 10% and 16% of guideline values, respectively. These results revealed that VOC emissions from household products may influence significantly indoor air quality. PMID:21381398

  2. 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.

  3. 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.

  4. 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

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

    PubMed

    Bennett, Joan W; Inamdar, Arati A

    2015-09-01

    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. 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...

  7. 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.

  8. 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.

  9. 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.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  11. [Process-based Emission Characteristics of Volatile Organic Compounds (VOCs) from Paint Industry in the Yangtze River Delta, China].

    PubMed

    Mo, Zi-wei; Niu, He; Lu, Si-hua; Shao, Min; Gou, Bin

    2015-06-01

    Understanding the volatile organic compounds (VOCs) emission characteristics from solvent usage industry is essential to reduce PM2.5 and O3 in Yangtze River Delta region. In this work, VOCs source characteristics of ship container, shipbuilding, wood, and automobile painting industry were measured using canister-GC-MS/FID analysis system. The results showed that VOCs emitted from these industrial sectors were mainly aromatics, such as toluene, xylene, and ethylbenzene, accounting for 79%-99% of total VOCs. The VOCs treatment facilities of activated carbon adsorption had little impact on changing the composition patterns of VOCs, while catalytic combustion treatments produced more alkenes. The combustion treatment of VOCs changed the maximum increment reactivity (MIR) of the VOCs emissions, and was thus very likely to change the ozone formation potentials. PMID:26387293

  12. 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...

  13. 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. PMID:25129414

  14. 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

  15. 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

  16. Plant volatile organic compounds (VOCs) in ozone (O3) polluted atmospheres: the ecological effects.

    PubMed

    Pinto, Delia M; Blande, James D; Souza, Silvia R; Nerg, Anne-Marja; Holopainen, Jarmo K

    2010-01-01

    Tropospheric ozone (O3) is an important secondary air pollutant formed as a result of photochemical reactions between primary pollutants, such as nitrogen oxides (NOx), and volatile organic compounds (VOCs). O3 concentrations in the lower atmosphere (troposphere) are predicted to continue increasing as a result of anthropogenic activity, which will impact strongly on wild and cultivated plants. O3 affects photosynthesis and induces the development of visible foliar injuries, which are the result of genetically controlled programmed cell death. It also activates many plant defense responses, including the emission of phytogenic VOCs. Plant emitted VOCs play a role in many eco-physiological functions. Besides protecting the plant from abiotic stresses (high temperatures and oxidative stress) and biotic stressors (competing plants, micro- and macroorganisms), they drive multitrophic interactions between plants, herbivores and their natural enemies e.g., predators and parasitoids as well as interactions between plants (plant-to-plant communication). In addition, VOCs have an important role in atmospheric chemistry. They are O3 precursors, but at the same time are readily oxidized by O3, thus resulting in a series of new compounds that include secondary organic aerosols (SOAs). Here, we review the effects of O3 on plants and their VOC emissions. We also review the state of current knowledge on the effects of ozone on ecological interactions based on VOC signaling, and propose further research directions. PMID:20084432

  17. 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.

  18. Projection of anthropogenic volatile organic compounds (VOCs) emissions in China for the period 2010-2020

    NASA Astrophysics Data System (ADS)

    Wei, Wei; Wang, Shuxiao; Hao, Jiming; Cheng, Shuiyuan

    2011-12-01

    The future (2010-2020) anthropogenic volatile organic compounds (VOCs) emissions in China were projected in this study using 2005 as the reference year. The projections are based on the assumptions of a lower population growth rate (less than 1%), continuous economic development with high GDP growth, and increased urbanization. The results show that the national VOCs emissions would continuously increase from 19.4 Tg in 2005 to 25.9 Tg in 2020, even if China's legislative standards for VOCs emissions are implemented effectively in the future (assumed as control scenario I). The contributions of various emission sources were found to differ greatly in the period of 2010-2020. Solvent utilization would become the largest contributor rising from 22% to 37%, along with an increase for industrial processes from 17% to 24%. However, road vehicle emissions would rapidly decrease from 25% to 11% due to the strict VOCs emission limit standards in China, along with the decrease for stationary fuel combustion from 23% to 16% caused by the reduction of domestic biofuel consumption. Additionally, there would be a notable divergence among provincial emissions. The developed eastern and coastal regions would emit more VOCs than the relatively underdeveloped western and inland regions. Moreover, this divergence grows in the future. When we assumed stricter control measures for solvent utilization and industrial processes (control scenario II) for that period, the projections revealed national VOCs emissions per year would remain at about 20 Tg, if exhaust after-treatment systems are installed in newly-built factories (after 2005) for the most important industrial sources, and the market shares of "low/zero-VOCs" products in paints, adhesives and printing ink raise to the present levels of developed countries. The emission abatements of the two types of measures were estimated to be similar. While scenario II indicates that the sectoral and provincial differences of VOCs emissions

  19. VOC (VOLATILE ORGANIC COMPOUND) FUGITIVE EMISSION PREDICTIVE MODEL - USER'S GUIDE

    EPA Science Inventory

    The report discusses a mathematical model that can be used to evaluate the effectiveness of various leak detection and repair (LDAR) programs on controlling volatile organic compound (VOC) fugitive emissions from chemical, petroleum, and other process units. The report also descr...

  20. 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

  1. 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. PMID:26386252

  2. 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.

  3. 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. PMID:23016284

  4. 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

  5. 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. PMID:19320266

  6. 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.

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. 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...

  12. 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. PMID:26708646

  13. 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.

  14. INTERNATIONAL COMPARISON EXPERIMENT ON THE DETERMINATION OF VOCS EMITTED FROM INDOOR MATERIALS USING SMALL TEST CHAMBERS

    EPA Science Inventory

    The paper discusses an interlaboratory comparison of three materials to assess the agreement among laboratories for characterizing volatile organic compounds emitted from indoor materials and products using small test chambers. esults from the 20 participating laboratories showed...

  15. 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

  16. 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. PMID:12046285

  17. 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.

  18. 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. PMID:25667057

  19. Emissions of Biogenic Volatile Organic Compounds and Observations of VOC Oxidation at Harvard Forest

    NASA Astrophysics Data System (ADS)

    McKinney, K. A.; Pho, T.; Vasta, A.; Lee, B. H.

    2009-12-01

    The contribution of biogenic volatile organic compounds (BVOCs) to oxidant concentrations and secondary organic aerosol (SOA) production in forested environments depends on the emission rates of these compounds. Recent findings have suggested that the emission rates of BVOCs and the range of species emitted could be larger than previously thought. In this study, Proton Transfer Reaction Mass Spectrometry (PTR-MS) was used to obtain fast (<1 Hz) measurements of the predominant BVOC species, including isoprene, monoterpenes, and oxygenated BVOCs, above the canopy at Harvard Forest (Petersham, MA) during the summers of 2005, 2007, and 2008. Together with vertical wind data, these measurements are used to determine fluxes of BVOCs out of the forest using the virtual disjunct eddy covariance method. Concentrations of additional VOCs, including methyl vinyl ketone + methacrolein and terpene oxidation products were also measured. Isoprene is the dominant emitted species, with peak emission rates and midday mixing ratios of ca. 4 mg isoprene m-2 h-1 and ca. 5 ppbv, respectively. Isoprene emission rates are expected to vary with temperature and radiation (PAR) levels, and are compared to standard emission algorithms based on these parameters. Interannual variability in isoprene emission rates is also observed, and contributing factors are explored. In contrast to isoprene, maximum monoterpene concentrations typically were less than 1 ppbv and occurred in the early evening, with a local minimum at midday. Monoterpene fluxes are about an order of magnitude smaller than those of isoprene. The amplitude of the flux diurnal cycle suggests monoterpene emissions at Harvard Forest may exhibit light dependence as well as temperature dependence. Fluxes of oxygenated VOCs, including methanol, acetone, methyl ethyl ketone, and oxygenated terpenes that have rarely been observed previously, are also reported, and the dependence of their emission rates on factors such as time of year

  20. EVALUATION OF INNOVATIVE LOW-VOLATILE ORGANIC COMPOUND (VOC) INDUSTRIAL MAINTENANCE (IM) COATINGS

    EPA Science Inventory

    The paper discusses a field evaluation of the feasibility of using alternative low-volatile organic compound (VOC) coatings to replace higher-VOC coatings. he evaluation includes chemical, performance, and outdoor exposure testing. he feasibility of five alternative coatings for ...

  1. Volatile organic compounds emitted from silver birch of different provenances across a latitudinal gradient in Finland.

    PubMed

    Maja, Mengistu M; Kasurinen, Anne; Holopainen, Toini; Kontunen-Soppela, Sari; Oksanen, Elina; Holopainen, Jarmo K

    2015-09-01

    Climate warming is having an impact on distribution, acclimation and defence capability of plants. We compared the emission rate and composition of volatile organic compounds (VOCs) from silver birch (Betula pendula (Roth)) provenances along a latitudinal gradient in a common garden experiment over the years 2012 and 2013. Micropropagated silver birch saplings from three provenances were acquired along a gradient of 7° latitude and planted at central (Joensuu 62°N) and northern (Kolari 67°N) sites. We collected VOCs emitted by shoots and assessed levels of herbivore damage of three genotypes of each provenance on three occasions at the central site and four occasions at the northern site. In 2012, trees of all provenances growing at the central site had higher total VOC emission rates than the same provenances growing at the northern site; in 2013 the reverse was true, thus indicating a variable effect of latitude. Trees of the southern provenance had lower VOC emission rates than trees of the central and northern provenances during both sampling years. However, northward or southward translocation itself had no significant effect on the total VOC emission rates, and no clear effect on insect herbivore damage. When VOC blend composition was studied, trees of all provenances usually emitted more green leaf volatiles at the northern site and more sesquiterpenes at the central site. The monoterpene composition of emissions from trees of the central provenance was distinct from that of the other provenances. In summary, provenance translocation did not have a clear effect in the short-term on VOC emissions and herbivory was not usually intense at the lower latitude. Our data did not support the hypothesis that trees growing at lower latitudes would experience more intense herbivory, and therefore allocate resources to chemical defence in the form of inducible VOC emissions. PMID:26093370

  2. 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.

  3. 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

  4. 40 CFR 60.502 - Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline terminals.

    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 Compound... Compound (VOC) emissions from bulk gasoline terminals. On and after the date on which § 60.8(a) requires a... with a vapor collection system designed to collect the total organic compounds vapors displaced...

  5. 40 CFR 60.502 - Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline terminals.

    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 Compound... Compound (VOC) emissions from bulk gasoline terminals. On and after the date on which § 60.8(a) requires a... with a vapor collection system designed to collect the total organic compounds vapors displaced...

  6. 40 CFR 60.502 - Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline terminals.

    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 Compound... Compound (VOC) emissions from bulk gasoline terminals. On and after the date on which § 60.8(a) requires a... with a vapor collection system designed to collect the total organic compounds vapors displaced...

  7. 40 CFR 60.502 - Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline terminals.

    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 Compound... Compound (VOC) emissions from bulk gasoline terminals. On and after the date on which § 60.8(a) requires a... with a vapor collection system designed to collect the total organic compounds vapors displaced...

  8. 40 CFR 60.502 - Standard for Volatile Organic Compound (VOC) emissions from bulk gasoline terminals.

    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 Compound... Compound (VOC) emissions from bulk gasoline terminals. On and after the date on which § 60.8(a) requires a... with a vapor collection system designed to collect the total organic compounds vapors displaced...

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

    PubMed

    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

  10. 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.

  11. 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.

  12. 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. PMID:26179779

  13. 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...

  14. Detection of volatile organic compounds (VOCs) from exhaled breath as noninvasive methods for cancer diagnosis.

    PubMed

    Sun, Xiaohua; Shao, Kang; Wang, Tie

    2016-04-01

    The detection of cancer at an early stage is often significant in the successful treatment of the disease. Tumor cells have been reported to generate unique cancer volatile organic compound (VOC) profiles which can reflect the disease conditions. The detection and analysis of VOC biomarkers from exhaled breath has been recognized as a new frontier in cancer diagnostics and health inspections owing to its potential in developing rapid, noninvasive, and inexpensive cancer screening tools. To detect specific VOCs of low concentrations from exhaled breath, and to enhance the accuracy of early diagnosis, many breath collection and analysis approaches have been developed. This paper will summarize and critically review the exhaled-breath VOC-related sampling, collection, detection, and analytical methods, especially the recent development in VOC sensors. VOC sensors are commonly inexpensive, portable, programmable, easy to use, and can obtain data in real time with high sensitivities. Therefore, many sensor-based VOC detection techniques have huge potential in clinical point-of-care use. PMID:26677028

  15. Assessment of ambient volatile organic compounds (VOCs) near major roads in urban Nanjing, China

    NASA Astrophysics Data System (ADS)

    Wang, P.; Zhao, W.

    2008-08-01

    Volatile organic compounds (VOCs) are a major component of atmospheric pollutants in Nanjing, a large city in the east of China. Accordingly, 12-h diurnal monitoring for ten consecutive days was performed adjacent to major roads in five districts, ca.1.5 m above ground level, in April, July and October 2006, and January 2007. The most numerous species of VOCs (benzene, toluene, ethylbenzene, m/ p-xylene, o-xylene, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, tetrachloromethane, trichloroethane and tetrachloroethane) were selected as the target pollutants for this field study of atmospheric distribution. The eleven VOCs were mostly found in gas phase due to their high vapor pressures. Gas-phase concentrations ranged between 0.6 and 67.9 μg m - 3 . Simultaneously, the levels of those VOCs measured near major roads were associated slightly with their regional background level. For all these areas, as expected, the high traffic area was the highest in terms of concentration. A positive correlation was also found between the VOC levels and traffic density. Our studies also provided VOC distribution, and vertical/horizontal profiles. The results show that traffic-related exposure to VOCs in major road microenvironments is higher than elsewhere and poses a potential threat to pedestrians, commuters, and traffic-exposed workers.

  16. Sesquiterpene volatile organic compounds (VOCs) are markers of elicitation by sulfated laminarine in grapevine

    PubMed Central

    Chalal, Malik; Winkler, Jana B.; Gourrat, Karine; Trouvelot, Sophie; Adrian, Marielle; Schnitzler, Jörg-Peter; Jamois, Frank; Daire, Xavier

    2015-01-01

    Inducing resistance in plants by the application of elicitors of defense reactions is an attractive plant protection strategy, particularly for grapevine (Vitis vinifera), which is susceptible to severe fungal diseases. Although induced resistance (IR) can be successful under controlled conditions, in most cases, IR is not sufficiently effective for practical disease control under outdoor conditions. Progress in the application of IR requires a better understanding of grapevine defense mechanisms and the ability to monitor defense markers to identify factors, such as physiological and environmental factors, that can impact IR in the vineyard. Volatile organic compounds (VOCs) are well-known plant defense compounds that have received little or no attention to date in the case of grape-pathogen interactions. This prompted us to investigate whether an elicitor, the sulfated laminarin (PS3), actually induces the production of VOCs in grapevine. An online analysis (proton-transfer-reaction quadrupole mass spectrometry) of VOC emissions in dynamic cuvettes and passive sampling in gas-tight bags with solid-phase microextraction-GC-MS under greenhouse conditions showed that PS3 elicited the emission of VOCs. Some of them, such as (E,E)-α-farnesene, may be good candidates as biomarkers of elicitor-IR, whereas methyl salicylate appears to be a biomarker of downy mildew infection. A negative correlation between VOC emission and disease severity suggests a positive role of VOCs in grape defense against diseases. PMID:26042139

  17. Solid phase microextraction: measurement of volatile organic compounds (VOCs) in Dhaka City air pollution.

    PubMed

    Hussam, A; Alauddin, M; Khan, A H; Chowdhury, D; Bibi, H; Bhattacharjee, M; Sultana, S

    2002-08-01

    A solid phase microextraction (SPME) technique was applied for the sampling of volatile organic compounds (VOCs) in ambient air polluted by two stroke autorickshaw engines and automobile exhausts in Dhaka city, Bangladesh. Analysis was carried out by capillary gas chromatography (GC) and GC-mass spectrometry (MS). The methodology was tested by insitu sampling of an aromatic hydrocarbon mixture gas standard with a precision of +/-5% and an average accuracy of 1-20%. The accuracy for total VOCs concentration measurement was about 7%. VOC's in ambient air were collected by exposing the SPME fiber at four locations in Dhaka city. The chromatograms showed signature similar to that of unburned gasoline (petrol) and weathered diesel containing more than 200 organic compounds; some of these compounds were positively identified. These are normal hydrocarbons pentane (n-C5H2) through nonacosane (n-C29H60), aromatic hydrocarbons: benzene, toluene, ethylbenzene, n-propylbenzene, n-butylbenzene, 1,3,5-trimethylbenzene, xylenes, and 1-isocyanato-3-methoxybenzene. Two samples collected near an autorickshaw station contained 783000 and 1479000 microg/m3 of VOCs. In particular, the concentration of toluene was 50-100 times higher than the threshold limiting value of 2000 microg/m3. Two other samples collected on street median showed 135000 microg/m3 and 180000 microg/m3 of total VOCs. The method detection limit of the technique for most semi-volatile organic compounds was 1 microg/m3. PMID:15328688

  18. 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

  19. 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. PMID:20012675

  20. 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

  1. 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).

  2. 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

  3. 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 PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Storage Vessels for Petroleum Liquids...

  4. 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...

  5. 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...

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. Volatile Organic Compounds (VOCs) variability at Western Europe mountain site (puy de Dôme, French)

    NASA Astrophysics Data System (ADS)

    Gaimoz, C.; Colomb, A.; Jacob, V.; Jaffrezo, J.; Sellegri, K.; Pichon, J.; Picard, D.; Ribeiro, M.; Bouvier, L.; Legrand, M.

    2010-12-01

    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 particulate equivalent black carbon (eqBC) are continuously monitored throughout the year. 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 also measured during an intensive campaign in June 2010. The analysis of VOCs collected in Tenax cartridges was achieved by using thermo-desorption coupled gas-chromatography with mass spectrometry (GC-MS). The results presented here are discussed in terms of observed levels, diurnal variability and sources influence of these gaseous pollutants. Different methods, including examination of ratio between compounds, comparison with other tracers (CO, BC, …) or other parameters (temperature, air masses origins, …), are used to help identifying main sources influencing VOCs variability. This is the first report of measurements on VOCs from a background French mountain site.

  11. Speciation of VOCs from Animal Feeding Operations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Environmental Pollution Agency (EPA) air consent agreement with animal feeding operations (AFO) specifies the use of EPA TO-15 for the speciation of volatile organic compounds (VOC) emitted from these facilities. However, compounds emitted from AFO are often both volatile and highly polar chara...

  12. Reduced volatile organic compound (VOC) ammunition coatings. Progress report, October 1994-September 1995

    SciTech Connect

    Duncan, J.L.

    1996-05-01

    Production requirements and film thickness limitations typically require that ammunition coating systems consist of a single film. This single film must provide the corrosion resistance of a primer plus such properties as color, gloss, and solvent resistance that are required of a topcoat, a compromise at best. Federal and local regulations resulting from the Clean Air Act and its amendments restrict the amount of VOC emitted during the application of protective coatings, and regulations on worker safety restrict exposure to hazardous materials such as chromates. These materials also generate hazardous wastes and the associated high disposal costs. This report summarizes progress in developing ammunition coatings that perform as well as or better than current systems, but at reduced VOC levels with chromate-free pigmentation.

  13. 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.

  14. MODEL FOR EVALUATION OF REFINERY AND SYNFUELS VOC (VOLATILE ORGANIC COMPOUNDS) EMISSION DATA. VOLUME 1. TECHNICAL REPORT AND APPENDIX A

    EPA Science Inventory

    The report describes the development of a model for estimating emissions of volatile organic compounds (VOCs) from petroleum refineries and synfuel plants. The model, responding to a need to define a consistent and comprehensive approach for estimating VOC emissions from these tw...

  15. MODEL FOR EVALUATION OF REFINERY AND SYNFUELS VOC (VOLATILE ORGANIC COMPOUNDS) EMISSION DATA. VOLUME 2. APPENDICES B AND C

    EPA Science Inventory

    The report describes the development of a model for estimating emissions of volatile organic compounds (VOCs) from petroleum refineries and synfuel plants. The model, responding to a need to define a consistent and comprehensive approach for estimating VOC emissions from these tw...

  16. 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...

  17. 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

    ... 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...

  18. 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

    ... 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...

  19. 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

    ... 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...

  20. 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

    ... 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...

  1. 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.

  2. 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.

  3. Volatile organic compounds (VOCs) in air from Nisyros Island (Dodecanese Archipelago, Greece): Natural versus anthropogenic sources.

    PubMed

    Tassi, F; Capecchiacci, F; Giannini, L; Vougioukalakis, G E; Vaselli, O

    2013-09-01

    This study presents the chemical composition of VOCs in air and gas discharges collected at Nisyros Island (Dodecanese Archipelago, Greece). The main goals are i) to discriminate between natural and anthropogenic VOC sources and ii) to evaluate their impact on local air quality. Up to 63 different VOCs were recognized and quantitatively determined in 6 fumaroles and 19 air samples collected in the Lakki caldera, where fumarolic emissions are located, and the outer ring of the island, including the Mandraki village and the main harbor. Air samples from the crater area show significant concentrations of alkanes, alkenes, cyclic, aromatics, and S- and O-bearing heterocycles directly deriving from the hydrothermal system, as well as secondary O-bearing compounds from oxidation of primary VOCs. At Mandraki village, C6H6/Σ(methylated aromatics) and Σ(linear)/Σ(branched) alkanes ratios <1 allow to distinguish an anthropogenic source related to emissions from outlet pipes of touristic and private boats and buses. PMID:23747819

  4. 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.

  5. 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. PMID:11605854

  6. Off-flavours in wines through indirect transfer of volatile organic compounds (VOCs) from coatings.

    PubMed

    Fumi, M D; Lambri, M; De Faveri, D M

    2009-05-01

    This paper assesses the impact of volatile organic compounds (VOCs) from the drying of coatings on the sensory characters of corks and wines. According to Italian National Standard Method 11021:2002, a small-scale chamber was used (1) to expose wines to the drying of coatings with both low and high VOCs, and (2) to expose corks to the same coatings. After exposure to the coatings, the corks were then placed in direct contact with wine. Different styles of white, red and rose wines were tested. In both directly exposed wines and in wines after contact with the exposed cork, the taste and smell off-flavour perception and intensity were assessed by a panel of eight experienced wine tasters using a five-point numerical scale according to International Organization for Standardization (ISO) standard methods. The results showed that the sensory characters of wines, especially taste, were influenced by the VOC content of the coatings. The taste off-flavour perception was found to be higher than the smell in wines exposed to coatings with either high or low VOCs contents. Analysis of variance (ANOVA) and Duncan analysis prove that: (1) panellist's answers were significantly different, (2) it was difficult to differentiate the off-flavour perception on the high-level scale, and (3) the panellist off-flavour perceptions versus wine style discriminated the wines into two groups (red and white/rose). For all the wine styles, Pearson's test showed no significant correlation between off-flavour perception levels and the main chemical characters of the wines. For the wines that were in direct contact with the exposed corks, the panellists detect the off-flavours according to the levels of VOCs in the coating and wine styles and they assessed the highest levels of alteration were to the taste. PMID:19680948

  7. [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

  8. 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

    2014-04-01

    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

  9. 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

  10. 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.

  11. 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.

  12. 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.

  13. 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. PMID:25464701

  14. 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. PMID:25508332

  15. Derived Emission Rates and Photochemical Production Rates of Volatile Organic Compounds (VOCs) Associated with Oil and Natural Gas Operations in the Uintah Basin, UT During a Wintertime Ozone Formation Event

    NASA Astrophysics Data System (ADS)

    Koss, A.; De Gouw, J. A.; Warneke, C.; Gilman, J.; Lerner, B. M.; Graus, M.; Yuan, B.; Edwards, P. M.; Brown, S. S.; Wild, R. J.; Roberts, J. M.; Bates, T. S.; Quinn, P.

    2014-12-01

    The Uintah Basin, an oil and natural gas extraction field in Utah, experienced extremely high levels of volatile organic compounds (VOCs) and ozone during the winter of 2013 - up to 100 ppmv carbon and 150 ppbv O3. Here we interpret VOCs measured during an ozone formation event from 31 Jan 2013 to 8 Feb 2013. Ratios of VOCs show strong diurnal cycles and week-long trends. A simple analysis was applied to ratios of aromatic VOCs measured by proton transfer reaction mass spectrometer (PTR-MS) to explain these trends and to estimate emission rates of aromatic VOCs from oil and natural gas extraction, VOC emission ratios relative to benzene, and ambient [OH]. The analysis incorporates the following assumptions: (1) the source composition of emitted VOCs and their emission rates were temporally and spatially constant, and (2) the removal of VOCs was governed by reaction with OH, diurnal profile of which is constrained by measured photolysis rates. The main findings are (1) the emission rate of methane, extrapolated from the emission rate of benzene, is on the same order as an independent estimate from aircraft measurements of methane in 2012, (2) the derived aromatic emission ratios are consistent with source contributions from both oil and gas producing wells, and (3) calculated daily OH concentrations are low, peaking at 1x106 molecules cm-3. The analysis was extended to investigate secondary production of oxygenated VOCs measured by PTR-MS. The analysis is able to explain daytime production, but it does not adequately explain nighttime behavior, which may be affected by complex deposition to snow and ice surfaces. The relative carbon mass of primary and secondary compounds was calculated and compared to observations. At the end of the ozone formation event (day 6), our analysis predicts that secondary (oxidized) VOCs should comprise about 40% of total carbon mass. However, only 12% of these compounds are accounted for by measured oxygenated VOCs and organic aerosol

  16. 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. PMID:15506617

  17. 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

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

  18. 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

    2015-01-01

    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. PMID:27506174

  19. 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. PMID:25016450

  20. 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

  1. 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

  2. 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

  3. 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

  4. 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...

  5. 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...

  6. Abatement of mixture of volatile organic compounds (VOCs) in a catalytic non-thermal plasma reactor.

    PubMed

    Karuppiah, J; Reddy, E Linga; Reddy, P Manoj Kumar; Ramaraju, B; Karvembu, R; Subrahmanyam, Ch

    2012-10-30

    Total oxidation of mixture of dilute volatile organic compounds was carried out in a dielectric barrier discharge reactor with various transition metal oxide catalysts integrated in-plasma. The experimental results indicated the best removal efficiencies in the presence of metal oxide catalysts, especially MnO(x), whose activity was further improved with AgO(x) deposition. It was confirmed water vapor improves the efficiency of the plasma reactor, probably due to the formation of hydroxyl species, whereas, in situ decomposition of ozone on the catalyst surface may lead to nascent oxygen. It may be concluded that non-thermal plasma approach is beneficial for the removal of mixture of volatile organic compounds than individual VOCs, probably due to the formation of reactive intermediates like aldehydes, peroxides, etc. PMID:22975253

  7. 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

  8. Spatial and seasonal variation and source apportionment of volatile organic compounds (VOCs) in a heavily industrialized region

    NASA Astrophysics Data System (ADS)

    Dumanoglu, Yetkin; Kara, Melik; Altiok, Hasan; Odabasi, Mustafa; Elbir, Tolga; Bayram, Abdurrahman

    2014-12-01

    Source apportionment is generally applied to a time series of pollutant concentrations measured at a single site. However, in a complex airshed having multiple pollutant sources, it may be helpful to collect samples from several sites to ensure that some of them have low contributions from specific sources. Ambient air samples (n = 160) were collected by passive sampling during four seasons in 2009 and 2010 at forty different sites in Aliaga, Turkey to determine the spatial, seasonal variations and possible sources of volatile organic compounds (VOCs). Fifty-eight VOCs (Σ58VOC) were detected. Σ58VOC concentrations ranged between 0.1 and 1770 μg m-3 (avg ± SD, 67 ± 193 μg m-3). Aliphatic hydrocarbons were generally predominant with a high percentage of contribution (31%-88%) at all sites. Aromatic VOCs were the second highest group (8-50%), followed by halogenated VOCs (1-24%) and oxygenated VOCs (0.04-5.9%). Highly variable spatial distribution of ambient VOC concentrations suggested that the major sources in this region were industrial plants. Generally, VOC concentrations were higher in summer than in winter probably due to increased volatilization from their sources at higher ambient temperatures. However, high atmospheric VOC concentrations were also observed in winter and fall near the petroleum refinery and petrochemical complex, probably due to the calm conditions and high atmospheric stability that is commonly encountered during the winter months in the area, restricting the dilution of pollutants. The newest version of EPA PMF (V5.0) (Positive Matrix Factorization) having the capability of handling multiple site data was used for source apportionment. Refinery and petroleum products, petrochemical industry, solvent use and industrial processes, and vehicle exhaust were the identified VOC sources in the study area, contributing 56%, 22%, 12%, and 10%, respectively to the Σ58VOC concentrations. Carcinogenic risks due to lifetime exposure to seven VOCs

  9. Biogenic VOCs including monoterpenes and functionalized aromatic compounds within mid-troposphere boreal biomass burning plumes

    NASA Astrophysics Data System (ADS)

    Purvis, Ruth; Hopkins, James; Lewis, Ally; Andrews, Stephen; Punjabi, Shalini; Bauguitte, Stephan; Lee, James; Palmer, Paul; Parrington, Mark

    2013-04-01

    Boreal forest fires are a significant source of chemicals to the atmosphere including numerous VOCs (volatile organic compounds) such as monoterpenes and aromatics compounds. These compounds can have a significant effect on the formation of ozone in the atmosphere and some are implicated in the generation of secondary oxidation products, which can lead to the formation of secondary organic aerosols. Observations made during the BORTAS (Quantifying the impact of Boreal forest fires on Tropospheric oxidants using Aircraft and Satellite) campaign are presented. Data was collected onboard the UK Research Aircraft using a fast response in situ GCMS; this campaign was the first time this instrument was deployed in the field. Enhanced mixing ratios of aliphatic hydrocarbons, isoprene and monoterpenes were observed in both fresh and aged biomass burning plumes, in addition to a range of aromatic compounds such as naphthalene, benzaldehyde and acetophenone. Secondary oxidation products were also observed including methacrolein and methyl vinyl ketone. Emission ratios of organic compounds to carbon monoxide concentrations were calculated and where possible compared to literature. For most simple hydrocarbon emission ratios a very good agreement with previous measurements were observed.

  10. Release of volatile organic compounds (VOCs) from the lung cancer cell line CALU-1 in vitro

    PubMed Central

    Filipiak, Wojciech; Sponring, Andreas; Mikoviny, Tomas; Ager, Clemens; Schubert, Jochen; Miekisch, Wolfram; Amann, Anton; Troppmair, Jakob

    2008-01-01

    Background The aim of this work was to confirm the existence of volatile organic compounds (VOCs) specifically released or consumed by lung cancer cells. Methods 50 million cells of the human non-small cell lung cancer (NSCLC) cell line CALU-1 were incubated in a sealed fermenter for 4 h or over night (18 hours). Then air samples from the headspace of the culture vessel were collected and preconcentrated by adsorption on solid sorbents with subsequent thermodesorption and analysis by means of gas chromatography mass spectrometry (GC-MS). Identification of altogether 60 compounds in GCMS measurement was done not only by spectral library match, but also by determination of retention times established with calibration mixtures of the respective pure compounds. Results The results showed a significant increase in the concentrations of 2,3,3-trimethylpentane, 2,3,5-trimethylhexane, 2,4-dimethylheptane and 4-methyloctane in the headspace of CALU-1 cell culture as compared to medium controls after 18 h. Decreased concentrations after 18 h of incubation were found for acetaldehyde, 3-methylbutanal, butyl acetate, acetonitrile, acrolein, methacrolein, 2-methylpropanal, 2-butanone, 2-methoxy-2-methylpropane, 2-ethoxy-2-methylpropane, and hexanal. Conclusion Our findings demonstrate that certain volatile compounds can be cancer-cell derived and thus indicative of the presence of a tumor, whereas other compounds are not released but seem to be consumed by CALU-1 cells. PMID:19025629

  11. 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. PMID:27214244

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

    PubMed

    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

  13. 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.

  14. Chemodiversity in the fingerprint analysis of volatile organic compounds (VOCs) of 35 old and 7 modern apple cultivars determined by proton-transfer-reaction mass spectrometry (PTR-MS) in two different seasons.

    PubMed

    Ciesa, Flavio; Höller, Irene; Guerra, Walter; Berger, Jennifer; Dalla Via, Josef; Oberhuber, Michael

    2015-05-01

    Volatile organic compounds (VOCs) are chemical species that play an important role in determining the characteristic aroma and flavor of fruits. Apple (Malus × domestica Borkh.) cultivars differ in their aroma and composition of VOCs. To determine varietal differences in the aroma profiles, VOCs emitted by 7 modern and 35 old apple cultivars were analyzed using Proton Transfer Reaction Mass Spectrometry (PTR-MS). PTR-MS is a rapid, reproducible, and non-destructive spectrometric technique for VOC analysis of single fruits, developed for direct injection analysis. In the present study, we analyzed the differences in the emission of VOCs from single fruits at harvest and after a storage period of 60±10 days, followed by 3 d of shelf life. Our results show that VOC profile differences among apple cultivars were more pronounced after storage than at harvest. Furthermore, chemodiversity was higher in old cultivars compared to modern cultivars, probably due to their greater genetic variability. Our data highlight the importance of storage and shelf life are crucial for the development of the typical aroma and flavor of several apple cultivars. The validity of the method is demonstrated by comparison of two different harvest years. PMID:26010667

  15. Modeling emissions of volatile organic compounds from silage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  16. 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...

  17. CONTROL OF INDUSTRIAL VOC (VOLATILE ORGANIC COMPOUND) EMISSIONS BY CATALYTIC INCINERATION. VOLUME 1. ASSESSMENT OF CATALYTIC INCINERATION AND COMPETING CONTROLS

    EPA Science Inventory

    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 incin...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  19. Volatile organic compounds (VOCs): Remediation for groundwater. (Latest citations from the Selected Water Resources Abstracts database). Published Search

    SciTech Connect

    Not Available

    1993-11-01

    The bibliography contains citations concerning groundwater contamination by volatile organic compounds (VOCs) and treatment technology for reclamation. Citations discuss treatments such as activated carbon, biological degradation, stripping, aeration, and catalytic oxidation. Articles discuss applications of these techniques to landfills, hazardous waste sites, and Superfund sites. (Contains a minimum of 201 citations and includes a subject term index and title list.)

  20. PARAMETRIC EVALUATION OF VOC/HAP (VOLATILE ORGANIC COMPOUNDS-HAZARDOUS/TOXIC AIR POLLUTANTS) DESTRUCTION VIA CATALYTIC INCINERATION

    EPA Science Inventory

    The report describes the use of a pilot-scale catalytic incineration unit/solvent generation system to investigate the effectiveness of catalytic incineration as a way to destroy volatile organic compounds (VOCs) and hazardous/toxic air pollutants (HAPs). Objectives of the study ...

  1. A Standardized Sampling Procedure for the Determination of Volatile Organic Compounds (VOC) Determined in Snow Samples

    NASA Astrophysics Data System (ADS)

    Kos, G.; Ariya, P. A.

    2005-12-01

    Snow samples were collected from different semi-remote and urban environments using a standardized sampling procedure in order to minimize sampling errors. Samples were collected in pre-cleaned amber glass and sterile HDPE containers. Glass bottles and all non-sterilized equipment were washed with low nutrient detergent, acid washed and rinsed with ultra-pure water. Samples were collected using pre-sterilized or acid-washed sampling tools and blanks, consisting of ultra-pure water, which were treated identically to the collected samples in to monitor contamination from sampling equipment and the different types of containers. Analysis for VOC was carried out with a previously described, but modified solid phase micro-extraction (SPME) pre-concentration method and determination of compounds using gas-chromatography with mass spectrometric detection (GC-MS) (1). Low concentrations required the use of larger sample volumes and splitless injection mode. Samples analyzed were collected in and around Montreal, Quebec (45.28 N/73.45 W) at Mont-Saint Hilaire (altitude: 415 m a.s.l.), Downtown Montreal and Parc Tremblant. We will present and compare results from all sites, and the implication for atmospheric processes will be discussed. References (1) Kos G, Ariya PA (2004), Determination of Volatile Organic Compounds in Snow Using Solid Phase Micro Extraction, Eos Trans. AGU, 85 (47), Fall Meet. Suppl., Abstract A11B-53

  2. Analysis of volatile organic compounds (VOCs) in the headspace of NCI-H1666 lung cancer cells.

    PubMed

    Sponring, Andreas; Filipiak, Wojciech; Ager, Clemens; Schubert, Jochen; Miekisch, Wolfram; Amann, Anton; Troppmair, Jakob

    2010-01-01

    Analysis of volatile organic compounds (VOCs) provides an elegant approach for cancer screening and disease monitoring, whose use is currently limited by a lack of validated cancer-derived metabolites, which may serve as biomarkers. The aim of the experiments presented here was to investigate the release and consumption of VOCs from the non small cell lung cancer cell line NCI-H1666, which was originally derived from a bronchoalveolar carcinoma.Following detachment by trypsinization suspended cells were incubated in a sealed fermenter for 21 hours. 200 ml of headspace from the cell culture were sampled, diluted with dry, highly purified air and preconcentrated by adsorption on three different solid sorbents with increasing adsorption strength. VOC-analysis was performed by thermodesorption-gas chromatography mass spectrometry (TD-GC-MS). In contrast to our previous studies experiments with NCI-H1666 cells only confirmed the consumption of several aldehydes, n-butyl acetate and the ethers methyl tert-butyl ether and ethyl tert-butyl ether, but no unequivocal release of VOCs was observed. Together with our previously published work these data indicate that the consumption of certain VOCs is commonly observed while their release shows cell line-restricted patterns, whose underlying causes are unknown. PMID:21263191

  3. PTR-MS analysis of reference and plant-emitted volatile organic compounds

    NASA Astrophysics Data System (ADS)

    Maleknia, Simin D.; Bell, Tina L.; Adams, Mark A.

    2007-05-01

    Proton transfer reaction-mass spectrometry (PTR-MS) was applied to the analysis of a series of volatile organic compounds (VOCs) that emit from various plants. These include a group of alcohols (methanol, ethanol and butanol), carbonyl-containing compounds (acetic acid, acetone and benzaldehyde), isoprene, acetonitrile, tetrahydrofuran (THF), pyrazine, toluene and xylene and a series of terpenes (p-cymene, camphene, 2-carene, limonene, [beta]-myrcene, [alpha]-pinene, [beta]-pinene, [gamma]-tepinene and terpinolene) and oxygen-containing terpenes (1,8-cineole and linalool). These mass spectral data were compared to an electron ionization (EI) database identifying that not all PTR-MS fragments were common to EI. PTR-MS studies of these reference compounds were utilized to identify VOCs emitted from Eucalyptus grandis leaf at a temperature range of 30-100 °C. In addition to protonated molecules (M + H)+, abundant proton-bound dimers or trimers were detected for alcohols, acetone, acetonitrile and THF. Abundant fragment ions attributed to the loss of water from these proton-bound clusters were also observed. The stability of butyl (C4H9+ m/z 57) and acetyl (CH3CO+ m/z 43) fragment ions directed the proton-transfer reactions of butanol and acetic acid. Abundant (M + H)+ ions were detected for pyrazine, THF, toluene and xylene, as well as for all terpenes except those containing oxygen. For linalool and 1,8-cineole, the loss of water generated an abundant fragment ion at m/z 137. PTR-MS fragmentation patterns for terpenes were proposed for m/z 81 (C6H9+), 93 (C7H9+), 95 (C7H11+), 107 (C8H11+), 109 (C8H13+), 119 (C9H11+), 121 (C9H13+) and 137 (loss of water for oxygen-containing terpenes; C10H17+). The relative abundances of (M + H)+ and fragments for all terpenes (except linalool) were dependent on the drift tube voltage and the optimum voltage for detection of molecular ions was different for various terpenes.

  4. Characterization of odorous compounds (VOC and carbonyl compounds) in the ambient air of Yeosu and Gwangyang, large industrial areas of South Korea.

    PubMed

    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

  5. 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. PMID:18313062

  6. Systemic Resistance Induced by Volatile Organic Compounds Emitted by Plant Growth-Promoting Fungi in Arabidopsis thaliana

    PubMed Central

    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. PMID:24475190

  7. 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. PMID:24475190

  8. Translational research to develop a human PBPK models tool kit-volatile organic compounds (VOCs).

    PubMed

    Mumtaz, M Moiz; Ray, Meredith; Crowell, Susan R; Keys, Deborah; Fisher, Jeffrey; Ruiz, Patricia

    2012-01-01

    Toxicity and exposure evaluations remain the two of the key components of human health assessment. While improvement in exposure assessment relies on a better understanding of human behavior patterns, toxicity assessment still relies to a great extent on animal toxicity testing and human epidemiological studies. Recent advances in computer modeling of the dose-response relationship and distribution of xenobiotics in humans to important target tissues have advanced our abilities to assess toxicity. In particular, physiologically based pharmacokinetic (PBPK) models are among the tools than can enhance toxicity assessment accuracy. Many PBPK models are available to the health assessor, but most are so difficult to use that health assessors rarely use them. To encourage their use these models need to have transparent and user-friendly formats. To this end the Agency for Toxic Substances and Disease Registry (ATSDR) is using translational research to increase PBPK model accessibility, understandability, and use in the site-specific health assessment arena. The agency has initiated development of a human PBPK tool-kit for certain high priority pollutants. The tool kit comprises a series of suitable models. The models are recoded in a single computer simulation language and evaluated for use by health assessors. While not necessarily being state-of-the-art code for each chemical, the models will be sufficiently accurate to use for screening purposes. This article presents a generic, seven-compartment PBPK model for six priority volatile organic compounds (VOCs): benzene (BEN), carbon tetrachloride (CCl(4)), dichloromethane (DCM), perchloroethylene (PCE), trichloroethylene (TCE), and vinyl chloride (VC). Limited comparisons of the generic and original model predictions to published kinetic data were conducted. A goodness of fit was determined by calculating the means of the sum of the squared differences (MSSDs) for simulation vs. experimental kinetic data using the

  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. 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

  11. 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.

  12. ASSESSMENT OF NEUROBEHAVIORAL RESPONSE IN HUMANS TO LOW-LEVEL VOLATILE ORGANIC COMPOUND (VOC) SOURCES

    EPA Science Inventory

    Occupants of sick buildings often complain of CNS symptoms including headache and memory loss, but little objective evidence of neurobehavioral effects exists. vailable evidence of neurobehavioral effects of low level VOC exposure representative of new buildings is reviewed. etho...

  13. 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. PMID:23584189

  14. 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.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

  16. 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.

  17. 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

  18. 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

  19. 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

  20. Sorption studies of VOCs (volatile organic compounds) related to soil/ground water contamination at LLNL (Lawrence Livermore National Laboratory)

    SciTech Connect

    Bishop, D.J.; Knezovich, J.P.; Rice, D.W. Jr.

    1989-08-01

    In 1980, Lawrence Livermore National Laboratory (LLNL) initiated a preliminary ground water study beneath and in the vicinity of the LLNL site in Livermore, California. Findings from that study indicated that volatile organic compounds (VOCs), primarily tetrachloroethylene (PCE) and trichloroethylene (TCE), were present in local ground water. Subsequent sampling results showed several locations with VOCs in the parts-per-billion range, and three areas where parts-per-million concentrations were detected. Subsequently, more than 200 wells were drilled and tested during investigations to assess the lateral and stratigraphic extent of ground water contamination and to understand the hydrogeologic characteristics under the Laboratory and adjacent affected areas. Although PCE and TCE predominate, dichloroethanes, dichloroethylenes, and carbon tetrachloride have been detected in ground water at concentrations exceeding California Department of Health Services recommended action levels. In order to predict the rate and extent of movement of the VOCs in ground water, it is essential to understand the sorptive properties of these compounds in relation to the subsurface soils that exist in this area. TCE and PCE were selected for study initially because of their predominance in the contaminant plume. Additional tests were performed using 1,2-dichloroethane (DCA), 1,2-dichloroethene (DCE), and chloroform (CF). 28 refs., 4 figs., 7 tabs.

  1. 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

    2015-06-01

    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. PMID:25971714

  2. 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. PMID:11289444

  3. 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

  4. RESPONSE OF PORTABLE VOC (VOLATILE ORGANIC COMPOUNDS) ANALYZERS TO CHEMICAL MIXTURES

    EPA Science Inventory

    The report gives the responses of two types of portable VOC analyzers (Century Systems OVA-108 and Bacharach TLV Sniffer), calibrated with methane and used to measure a variety of chemical vapor mixtures. Instrument response data for both binary and ternary mixtures of selected c...

  5. 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.

  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. 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

  8. Volatile organic compounds (VOCs) measured at an urban site of Beijing: intercomparisons, emission ratios and factor analysis

    NASA Astrophysics Data System (ADS)

    Yuan, B.; Shao, M.; De Gouw, J. A.; Bon, D.; Wang, M.; Lu, S.; Zeng, L.; Zhang, Q.; Liu, Y.

    2011-12-01

    A proton transfer reaction mass spectrometer (PTR-MS) were used to measure volatile organic compounds (VOCs) in August - September, 2010 (summer) and December, 2010 - January, 2011 (winter) at an urban site on campus of Peking University. During the summer campaign, other instruments were also deployed at the site, including a custom-built GC-MS/FID, a GC-FID/PID, whole air samples (WAS) collected in canisters, and DNPH cartridges. VOCs concentrations measured by PTR-MS in the summer campaign compared well with the GC methods for most of the measured compounds. VOCs concentrations in winter strongly correlated with the combustion tracer CO for both hydrocarbons and oxygenates VOCs (OVOCs) and emission ratios to CO were calculated from linear fits of ambient concentrations. Emission ratios of aromatics in winter were significantly lower than those in summer, which may be due to: (1) higher CO emissions from coal burning for space heating in winter of Beijing; (2) higher industrial/solvent evaporations of aromatics in summer. The VOCs dataset with 19 species from PTR-MS and 56 species from GC-MS/FID was used for PMF analysis. A solution of five factors with no rotation (fPeak=0) was determined to be the best fit. Uncertainties of PMF analysis were explored by bootstrap method. The five factors included a fresh primary emissions factor (Factor 1, 27%), an aged primary emissions factor (Factor 2, 19%), a secondary & aged factor (Factor 3, 33%), a biogenic factor (Factor 4, 4%) and an industrial-like factor (Factor 5, 17%). The fresh and aged primary factor correlated well with NOx and CO, respectively. And the secondary & aged factor correlated well with PAN and Ox (O3+NO2). The contributions in different factors for various hydrocarbons are dependent on their reactivity. Comparing the obtained factor profiles shows that the aged primary emission factor and the secondary & aged factor are photochemically connected with the fresh primary emission factor. It suggested

  9. Monitoring plant bioremediation of volatile organic compounds (VOCs) using open path Fourier transform infrared (FT-IR) spectrometry

    SciTech Connect

    Hoffman, R.M.; Visser, V.P.; Davis, L.C.; Erickson, L.E.; Muralidharan, N.; Hammaker, R.M.; Fateley, W.G.

    1994-12-31

    This study addresses a viable and natural solution to the elimination of volatile organic compounds (VOCs), which are pollutants, through the bioremediation process. Plants and associated rhizosphere bacteria have the ability to bioremediate both volatile and non-volatile organic compounds. For volatile compounds, intersystem transfer by transpiration may be a matter for concern when plants interact with such materials. The authors have monitored, using FT-IR, the potential transfer from subsurface water in the presence of toluene-adapted alfalfa plants. These experiments show that the plants and/or their associated micro-organisms effectively degrade toluene so that potential intersystem transfer of VOCs by transpiration may be quite manageable with adapted plants. Presently, the authors are monitoring 1,1,1-trichloroethane (TCA), chloroform (CHCl{sub 3}), and, trichloroethylene (TCE) from the subsurface water and the gas phase above the plants. TCA does not show an indication of degradation, whereas TCE does. Methane is produced in the groundwater but not transferred to the atmosphere, indicating the presence of a consortium of methanogens and methanotrophs in this soil. The TCE presumably is the substrate for methane production based on chloride ion accumulation. The majority of the TCE must be degraded aerobically to yield CO{sub 2} in the vadose zone. The FT-IR spectrometer can quickly determine and analyze contaminants in the gas phase, groundwater and plant tissue.

  10. 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.

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

    PubMed Central

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

    2015-01-01

    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. PMID:25674036

  12. 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. PMID:26010216

  13. Non-methane volatile organic compounds predict odor emitted from five tunnel ventilated broiler sheds.

    PubMed

    Murphy, Kathleen R; Parcsi, Gavin; Stuetz, Richard M

    2014-01-01

    Non-methane volatile organic compounds (NMVOCs) emitted from mechanically ventilated poultry sheds in similar stages (32-36 d) of broiler production were measured by thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS), then identified using parallel factor analysis (PARAFAC2) and the NIST11 database. Calibration models predicting odor measured by dilution olfactometry from NMVOC concentrations via orthogonal projection to latent structures (O-PLS) made good predictions (Rp(2)=0.83-0.87, RMSEp=137-175OU) using one to eight NMVOCs with either one or two latent variables representing odor concentration and character, respectively. Similar changes in odorant composition were observed in each sampling campaign, with samples collected early in the day more odorous and more sulfurous than samples collected later in the day. High litter moisture favored sulfur-containing odorants over alcohols, aldehydes and ketones but had little bearing on perceived odor, whereas high bird density favored alcohols, aldehydes and ketones over sulfur-containing odorants. Eight VOCs that were important predictors of odor across all sheds in order of decreasing importance were dimethyl sulfide (DMS), dimethyl trisulfide (DMTS), 2-3 butanedione, 3-methyl-butanal, 1-butanol, 3-methyl-1-butanol, acetoin, and 2-butanone. Four additional NMVOCs also influenced perceived odor although less predictably; these were n-hexane, 2-butanol, dimethyl disulfide (DMDS), and 1-octen-3-ol. All of the odorants are associated with microbial or fungal activity in the litter and manure, except n-hexane, which may originate from hexane-extracted soybean meal in the chicken feed. The organosulfides measured in this study may have arisen from the field sites as well as from the degradation of thiols captured on sorbent tubes during analysis by TD-GC/MS. PMID:24188627

  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. 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

  16. Crossreactivity between the light-emitting systems of distantly related organisms: Novel type of light-emitting compound

    PubMed Central

    Dunlap, Jay C.; Hastings, J. W.; Shimomura, Osamu

    1980-01-01

    Dinoflagellate luciferin has been found to crossreact and emit light with euphausid photoprotein; and euphausid fluorescent substance gives luminescence with dinoflagellate luciferase. Luciferin and the fluorescent substance, both highly unstable and fluorescent compounds, are biochemically similar but not identical. Preliminary spectral and chemical data suggest that both compounds contain an open-chain polypyrrole structure, novel among compounds so far known to be involved in light emission in any biological system. The dinoflagellates and euphausids are phylogenetically distant; the possibility that the latter obtain the molecule nutritionally from the former is suggested. PMID:16592787

  17. Investigation of the acclimatization period: example of the microbial aerobic degradation of volatile organic compounds (VOCs).

    PubMed

    Bayle, Sandrine; Malhautier, Luc; Degrange, Valérie; Godon, Jean-Jacques; Fanlo, Jean-Louis

    2009-01-01

    The aim of this study is to better evaluate the occurrence of an acclimatization-enrichment period, defined as a selection period of consortia having the capability to biodegrade pollutants. In order to perform this evaluation, two experimental strategies were carried out and the results were studied carefully. Two laboratory-scale reactors were inoculated with activated sludge from an urban treatment plant. During the experiment, these reactors were supplied with a gaseous effluent containing VOCs. For both reactors, the composition is different. Three parameters were monitored to characterize the microflora: bacterial activities, bacterial densities, and the genetic structure of Bacteria and Eukarya domains (Single Strand Conformation Polymorphism fingerprint). The obtained results showed that the resultant biodegradation functions were equivalent. The bacterial community structure differs even if six co-migrated peaks were observed. These data suggest that the microbial communities in both reactors were altered differently in response to the treatment but developed a similar capacity to remove VOCs at the issue of this period. Furthermore, it is suggested that the experimental strategies developed in this work lead to an enrichment in terms of functionality and microbial diversity almost equivalent. PMID:19901452

  18. 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

  19. Environmental protection investigations and corrections series: Distribution of VOCs (volatile organic compounds) in round water in the southeast area of LLNL and vicinity

    SciTech Connect

    Dresen, M.D.; Nichols, E.M.

    1986-12-01

    Lawrence Livermore National Laboratory (LLNL) drilled 22 soil borings and 25 monitor wells to investigate the distribution of volatile organic compounds (VOCs) in ground water in the southeast area of LLNL and vicinity. Samples of saturated and unsaturated soil and ground water were collected and analyzed for VOCs. We have used these geologic and chemical data to define the vertical and horizontal distribution of VOCs in ground water. Ground water flow and VOC migration appear to be generally southward in the study area and are integrally related to the subsurface geology. The relatively shallow depth of the low-permeability, low piezometric head, lower member of the Livermore Formation in the study area has induced a significant downward gradient, apparently causing ground water and VOCs to migrate southward in permeable sediments near the contact between the upper and lower members of the Livermore Formation. Trichloroethylene (TCE), tetrachloroethylene (PCE), 1,1-dichloroethylene (1,1-DCE), and carbon tetrachloride (CCl/sub 4/) have been detected in ground water in the study area in concentrations exceeding action levels recommended by the California Department of Health Services (DOHS). TCE is the predominant VOC in the study area. Ground water chemistry and site history data indicate that there are three main sources of VOCs in ground water in the study area and vicinity. A suspected VOC source just south of Building 518 is characterized by TCE with low concentrations of 1,1-DCE, PCE, and CCl/sub 4/. A second VOC source in the Building 612 yard/Building 514 area is characterized by higher concentrations of 1,1-DCE and CCl/sub 4/ relative to TCE. A third source in the Taxi Strip/Old Salvage Yard area north of the study area is characterized by TCE with or without very low concentrations of CCl/sub 4/.

  20. 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

  1. 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.

  2. 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.

  3. Surface-enhanced Raman scattering (SERS)-based volatile organic compounds (VOCs) detection using plasmonic bimetallic nanogap substrate

    NASA Astrophysics Data System (ADS)

    Wong, Chi Lok; Dinish, U. S.; Buddharaju, Kavitha Devi; Schmidt, Michael Stenbæk; Olivo, Malini

    2014-08-01

    In this paper, we present surface-enhanced Raman scattering (SERS)-based volatile organic compounds (VOCs) detection with bimetallic nanogap structure substrate. Deep UV photolithography at the wavelength of 250 nm is used to pattern circular shape nanostructures. The nanogap between adjacent circular patterns is 30 ± 5 nm. Silver (30 nm) and gold (15 nm) plasmonic active layers are deposited on the nanostructures subsequently. SERS measurements on different concentrations of acetone vapor ranged from 0.7, 1.5, 3.5, 10.3, 24.5 % and control have been performed with the substrate. The measurement results are found reproducible, and the detection limit is found to be 9.5 pg (acetone molecule). The detection sensitivity is 28.7 % higher than that of the recent reported leaning silicon nanopillar substrate. With further system miniaturization, the sensing technique can work as a portable SERS-based VOCs detection platform for point-of-care breath analysis, homeland security, chemical sensing and environmental monitoring.

  4. Introduction of a sink-diffusion model to describe the interaction between volatile organic compounds (VOCs) and material surfaces.

    PubMed

    Jørgensen, R B; Dokka, T H; Bjørseth, O

    2000-03-01

    A sink-diffusion model to describe the interaction between material surfaces and volatile organic compounds (VOCs) in indoor air has been introduced. The model is based on adsorption/desorption on the material surfaces and diffusion into the materials. Test chamber experiments with exposure of nylon carpet and polyvinyl chloride (PVC) covering against alpha-pinene and toluene were used to validate the model and to make comparisons with a sink model based on the Langmuir adsorption isotherm. The results showed that the sink-diffusion model gave a better description of the desorption curve than the Langmuir model. The model predictions improved with increasing sorption effect. The Langmuir model gave good predictions of relative weak sorption effects, whereas the sink-diffusion model improved the predictions for stronger sorption effects. In this case, nylon carpet showed substantial stronger sorption than PVC covering and alpha-pinene showed stronger sorption than toluene. Controlled field experiments with combinations of building materials and a mixture of VOCs, encountered in real indoor environments, are needed to further validate the sink-diffusion model. PMID:10842458

  5. 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.

  6. 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.

  7. 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

  8. 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.

  9. 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

    2014-01-01

    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. PMID:24968328

  10. Pollution profiles, health risk of VOCs and biohazards emitted from municipal solid waste transfer station and elimination by an integrated biological-photocatalytic flow system: a pilot-scale investigation.

    PubMed

    Li, Guiying; Zhang, Zhengyong; Sun, Hongwei; Chen, Jiangyao; An, Taicheng; Li, Bing

    2013-04-15

    Volatile organic compounds (VOCs) and biohazards air pollution in municipal solid waste transfer station were investigated. As compressor working, the concentrations of almost all quantified 14 VOCs (0.32-306.03 μg m(-3)) were much higher than those as compressor off (0-13.31 μg m(-3)). Comparatively, only 3 VOCs with extremely low concentrations could be detected at control area. Total microorganism was 7567 CFU m(-3) as compressor working, which was 1.14 and 6.22 times higher than that of compressor off and control area, respectively. Bacteria were the most abundant microorganism at all three sampling places. At pilot-scale, during whole 60-day treatment, for VOCs, the average removal efficiencies were over 92% after biotrickling filter-photocatalytic (BTF-PC) treatment. Although non-cancer and cancer risks of some VOCs were over the concern level before treatment, almost all VOCs were removed substantially and both potential risks were below the concern after BTF-PC treatment. Additionally, biohazard concentrations decreased dramatically and air quality was purified from polluted to cleanness after PC treatment. All results demonstrated that the integrated technology possessed high removal capacity and long stability for the removal of VOCs and biohazards at a pilot scale. PMID:23434489

  11. Treatment of volatile organic compounds from polyurethane and epoxy manufacture by a trickle-bed air biofilter.

    PubMed

    Chang, K; Lu, C; Lin, M

    2001-01-01

    The objective of this study was to evaluate the performance of a trickle-bed air biofilter (TBAB) for the removal of volatile organic compound (VOC) produced during polyurethane (PU) and epoxy manufacture. The major VOCs emitted are ethyl acetate (EA) for PU and EA and xylene for epoxy production. For the treatment of VOCs emitted during PU production, the employed coal carbon appears to be efficient as a VOC concentration buffer in the biofiltration of waste gases. Based on the results of EA and total hydrocarbon (THC) removal, it was concluded that the TBAB is suitable for controlling VOC emission during PU manufacture. For the treatment of VOCs emitted during epoxy production, it was found that the performance of the TBAB is relatively poor due to the lack of VOC sources. However, this problem could be easily solved by mixing the VOCs emitted during PU and epoxy manufacture. PMID:16233071

  12. 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.

  13. CONTROL OF INDUSTRIAL VOC (VOLATILE ORGANIC COMPOUND) EMISSIONS BY CATALYTIC INCINERATION. VOLUME 4. CATALYTIC INCINERATOR PERFORMANCE AT INDUSTRIAL SITE C-2

    EPA Science Inventory

    Radian Corporation is conducting a testing program for the U.S. Environmental Protection Agency to evaluate the performance of catalytic incinerators that are applied to industrial processes for volatile organic compound (VOC) control. This report documents the results of the per...

  14. CONTROL OF INDUSTRIAL VOC (VOLATILE ORGANIC COMPOUND) EMISSIONS BY CATALYTIC INCINERATION. VOLUME 8. CATALYTIC INCINERATOR PERFORMANCE AT INDUSTRIAL SITE C-6

    EPA Science Inventory

    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 incin...

  15. CONTROL OF INDUSTRIAL VOC (VOLATILE ORGANIC COMPOUND) EMISSIONS BY CATALYTIC INCINERATION. VOLUME 7. CATALYTIC INCINERATOR PERFORMANCE AT INDUSTRIAL SITE C-5

    EPA Science Inventory

    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 incin...

  16. CONTROL OF INDUSTRIAL VOC (VOLATILE ORGANIC COMPOUND) EMISSIONS BY CATALYTIC INCINERATION. VOLUME 5. CATALYTIC INCINERATOR PERFORMANCE AT INDUSTRIAL SITE C-3

    EPA Science Inventory

    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 incin...

  17. SOURCE RECEPTOR STUDY OF VOLATILE ORGANIC COMPOUNDS AND PARTICULATE MATTER IN THE KANAWHA VALLEY, WV - PART II: ANALYSIS OF FACTORS CONTRIBUTING TO VOC AND PARTICLE EXPOSURES

    EPA Science Inventory

    The Kanawha Valley region of West Virginia includes a deep river valley with a large population living in close proximity to many potential sources of ambient volatile organics compounds (VOCs). he Valley runs approximately 100 km from Alloy to Nitro and is between 100 and 200 m ...

  18. 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.

  19. Analysis of organic compounds (VOC) in the forest air of the Southern Black Forest

    SciTech Connect

    Juettner, F.

    1986-01-01

    The volatile organic compounds of forest air (Kaelbelescheuer, Southern Black Forest) and, for comparison, suburban air (Tuebingen) were qualitatively analyzed by gas chromatographic and mass spectrometric methods. 94 Individual compounds were identified, 6 of them belonged to biogenic monoterpenes (..cap alpha..-pinene, ..delta..3-carene, myrcene, limonene, eucalyptol, camphene). While the monoterpenes were enriched in forest air, a similar collection of the pollution products was observed in both locations. Predominant substances were aromatic compounds (toluene, ethylbenzene, benzene, xylenes, ethyltoluenes, pseudocumene and naphthalene) which can be regarded as constituents of vehicle exhaust fumes and incineration processes. Other important substances in forest air were various solvents, of which butyl acetate, isobutyl acetate, tetrachloroethylene and trichloroethylene, butanol-1, and several ketones were prominent species.

  20. 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.

  1. 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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  3. [Oxidation behavior and kinetics of representative VOCs emitted from petrochemical industry over CuCeOx composite oxides].

    PubMed

    Chen, Chang-Wei; Yu, Yan-Ke; Chen, Jin-Sheng; He, Chi

    2013-12-01

    CuCeOx composite catalysts were synthesized via coprecipitation (COP-CuCeO,) and incipient impregnation (IMP-CuCeOx) methods, respectively. The physicochemical properties of the samples were characterized by XRD, low-temperature N2 sorption, H2-TPR and O2-TPD. The influences of reactant composition and concentration, reaction space velocity, O2 content, H2O concentration, and catalyst type on the oxidation behaviors of benzene, toluene, and n-hexane emitted from petrochemical industry were systematically investigated. In addition, the related kinetic parameters were model fitted. Compared with IMP-CuCeOx, COP-CuCeOx had well-dispersed active phase, better low-temperature reducibility, and more active surface oxygen species. The increase of reactant concentration was unfavorable for toluene oxidation, while the opposite phenomenon could be observed in n-hexane oxidation. The inlet concentration of benzene was irrelevant to its conversion under high oxidation rate. The introduction of benzene obviously inhibited the oxidation of toluene and n-hexane, while the presence of toluene had a positive effect on beuzene conversion. The presence of n-hexane could promote the oxidation of toluene, while toluene had a negative influence on e-hexane oxidation. Both low space velocity and high oxygen concentration were beneficial for the oxidation process, and the variation of oxygen content had negligible effect on n-hexane and henzene oxidation. The presence of H2O noticeably inhibited the oxidation of toluene, while significantly accelerated the oxidation procedure of henzene and n-hexane. COP-CuCeOx had superior catalytic performance for toluene and benzene oxidation, while IMP-CuCeOx showed higher n-hexane oxidation activity under dry condition. The oxidation behaviors under different conditions could be well fitted and predicted by the pseudo first-order kinetic model. PMID:24640915

  4. 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.

  5. A Comparison of volatile organic compound profiles from bacteria on poultry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In recent years the characterization of volatile organic compounds (VOCs) emitted from food-borne bacteria has prompted studies on the development of approaches to utilize the profile of volatiles emitted as a way of detecting contamination. We have examined VOCs from poultry with this in mind. Patt...

  6. Volatile Organic Compounds Produced by Bacteria from the Poultry Processing Environment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In recent years the characterization of volatile organic compounds (VOCs) emitted from food-borne bacteria has prompted studies on the development of approaches to utilize the profile of volatiles emitted as a way of detecting contamination. We have examined VOCs from poultry with this in mind. Patt...

  7. Volatile compounds emitted by sclerotia of Sclerotinia minor, Sclerotinia sclerotiorum, and Sclerotium rolfsii.

    PubMed

    Fravel, Deborah R; Connick, William J; Grimm, Casey C; Lloyd, Steven W

    2002-06-19

    Volatile compounds emitted by sclerotia of Sclerotinia minor, Sclerotinia sclerotiorum, and Sclerotium rolfsii were identified by solid phase microextraction followed by gas chromatography and mass spectometry. Both S. minor and S. sclerotiorum emitted 2-methylenebornane and 2-methylisoborneol. In addition, S. minor emitted mesityl oxide, gamma-butyrolactone, cis- and trans-linalool oxide, linalool, and trans-nerolidol. S. sclerotiorum emitted 2-methyl-2-bornene, 1-methylcamphene, and a diterpene with a molecular weight of 272. Sclerotium rolfsii did not emit any of these compounds but did emit delta-cadinene and cis-calamenene. Chemicals emitted by S. minor and S. sclerotiorum were tested to determine if they could stimulate germination of conidia of Sporidesmium sclerotivorum, a mycoparasite on sclerotia of Sclerotinia spp. Chemicals were tested at 1 part per billion to 100 parts per million, both in direct contact with conidia and near, but not in, physical contact. None of the chemicals alone nor a combination of all chemicals induced germination of conidia of S. sclerotivorum. PMID:12059156

  8. 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.

  9. 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. PMID:27016807

  10. 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.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  12. 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

  13. 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

  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. 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

  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 Energy's (DOE's) 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 1970's. 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. Volatile Organic Compounds (VOCs)

    MedlinePlus

    ... Air Duct Cleaning Asthma Health, Energy Efficiency and Climate Change Flood Cleanup Home Remodel Indoor airPLUS Mold Radon ... menu Learn the Issues Air Chemicals and Toxics Climate Change Emergencies Greener Living Health and Safety Land and ...

  18. [Characteristics of odors and VOCs from sludge direct drying process].

    PubMed

    Chen, Wen-He; Deng, Ming-Jia; Luo, Hui; Zhang, Jing-Ying; Ding, Wen-Jie; Liu, Jun-Xin; Liu, Jun-Xin

    2014-08-01

    Co-processing sewage sludge by using the high-temperature feature of cement kiln can realize harmless disposal and energy recycling. In this paper, investigation on characteristics of the flue gas from sludge drying process was carried out in Guangzhou Heidelberg Yuexiu Cement Co., LTD. The composition and the main source of odors and volatile organic compounds (VOCs) emitted during the drying process were analyzed, aimed to provide scientific basis for the treatment of sewage sludge. Results showed that there were a large number of malodorous substances and VOCs in the flue gas. Sulfur dioxide and other sulfur-containing compounds were the main components in the malodorous substances, while benzene derivatives were predominant in VOCs. The compositions of odors and VOCs were influenced by the characteristics of the sludge and the heat medium (kiln tail gas). Total organic compounds in the sludge were significantly decreased after drying. Other organic substances such as volatile fatty acid, protein, and polysaccharide were also obviously reduced. The organic matter in sludge was the main source of VOCs in the flue gas. Part of sulfurous substances, such as sulfur dioxide, carbon disulfide, were from sulfur-containing substances in the sludge, and the rest were from the kiln tail gas itself. PMID:25338358

  19. Simulation Chamber Investigations of Secondary Organic Aerosol Formation From Boreal Tree Emissions: Dependence on VOC Classes

    NASA Astrophysics Data System (ADS)

    Kiendler-Scharr, A.; Mentel, T. F.; Kleist, E.; Hohaus, T.; Mensah, A.; Spindler, C.; Tillmann, R.; Uerlings, R.; Dal Maso, M.; Rudich, Y.; Juergen, W.

    2008-12-01

    A considerable fraction of the organic aerosol component is of secondary origin, meaning it is formed through oxidation of volatile organic compounds (VOCs). Plant emissions, e.g. monoterpenes and sesquiterpenes, are a major source of VOCs in the troposphere. So far most laboratory and simulation chamber investigations on the potential to form secondary organic aerosols (SOA) from plant emissions focused on single VOCs such as a-pinene. In this study we investigated the formation and growth of SOA by ozonolysis and/or photo-oxidation of the VOCs emitted by several tree species such as spruce, pine and birch. The experiments were performed in the Plant chamber of the ICG-3 in Jülich under well defined conditions for the plant. VOC emissions were transferred to a reaction chamber which was operated as a continuously stirred tank reactor. SOA formation from the VOCs was initiated by an excess of ozone and OH radicals. The results are compared to a reference study with a-pinene as the only SOA precursor. Our results indicate that the general laboratory approach of studying the formation of SOA from single components can lead to a bias in both the mass yields and the mass spectral signatures observed. Plots of maximum SOA volumes versus the total amount of carbon fed into the reaction chamber led to approximately linear relationships. The intercepts of these plots were seen as threshold for SOA formation. It was observed that this threshold was lower for the mixture of VOCs emitted from spruce, pine, and birch than for a-pinene as single compound. We therefore conclude that the threshold for SOA formation from real plant mixtures may be much lower than the threshold obtained from laboratory experiments that were focussed on single VOCs. SOA formation from stress induced VOCs will be compared to non stress induced emissions. Possible feedbacks of climate change to VOC emissions and aerosol formation will be discussed based on our experimental observations.

  20. 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

  1. 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.

  2. Rapid determination of volatile compounds emitted from Chimonanthus praecox flowers by HS-SPME-GC-MS.

    PubMed

    Deng, Chunhui; Song, Guoxin; Hu, Yaoming

    2004-01-01

    A novel rapid, simple and solvent-free method was developed for determination of the volatile compounds from the flowers of Chimonanthus praecox Link using headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS). The SPME conditions were firstly optimized and applied to sampling of the volatile compounds emitted from living Chimonanthus praecox L. flowers and excised Chimonanthus praecox L. flowers. Thirty-one compounds emitted from living flowers were identified for the first time, which mainly included 4-methyl-1,3-pentadiene (2.0%), a-phellandrene (4.7%), benzyl methanol (11.1%), trans-linalool oxide (furanyl ring) (5.3%), a-linalool (36.0%), methyl salicylate (24.5%) and acetic acid benzyl ester (5.9%). Comparing the emission from living flowers and excised flowers, twenty-eight compounds were found to be detected in the two emissions, and three compounds, n-pentadecane, n-cetane and n-heptadecane, were only found in the emission from the living flowers, which shows that they might be biomarker compounds. PMID:15540594

  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. 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.

  5. 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.

  6. 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. PMID:26687162

  7. 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.

  8. Uptake of VOC by sunflower

    NASA Astrophysics Data System (ADS)

    Folkers, A.; Miebach, M.; Kleist, E.; Wildt, J.

    2003-04-01

    To study potential VOC uptake by plants we exposed sunflower (Helianthus annuus) to different VOC in continuously stirred tank reactors. For many VOC like methanol, ethanol, acetone, methylvinylketone, isoprene or limonene no uptake was detectable within the accuracy of our analytic set up. Other VOC like hexanal, octanal, (E)-3-hexenol and nopinone were taken up by sunflower. The uptake was related to stomatal aperture. Obviously, these VOC enter the plants through stomata. In case of hexanal, octanal, and (E)-3-hexenol the uptake was only limited by stomatal aperture implying that these VOC are rapidly metabolised. For nopinone the uptake seems to be limited by a slow metabolization. Estimations of deposition velocities showed that dry deposition of these compounds cannot be neglected as sink if diffusion through stomata is the limiting step for dry deposition. In such cases the lifetime with respect to dry deposiotion is comparable to the lifetime with respect to oxidation by hydroxyl radicals.

  9. 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.

  10. 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

  11. 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.

  12. 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.

  13. 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

  14. 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.

  15. 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

  16. 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. PMID:26726407

  17. 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.

  18. 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...

  19. Balanced charge injection in multilayer polymer light-emitting diode with water soluble nonconjugated polymer dispersed by ionic compounds

    NASA Astrophysics Data System (ADS)

    Park, Dong-Kyu; Chun, A.-Rum; Kim, Soo-Hong; Kim, Min-Sook; Kim, Choong-Gi; Kwon, Tae-Woo; Cho, Seong-Jin; Woo, Hyung-Suk; Lee, Jae-Gyoung; Lee, Suck-Hyun; Guo, Zhi-Xin

    2007-07-01

    The authors have fabricated highly efficient polymeric light-emitting diode (PLED) from ionic compound dispersed water soluble nonconjugated polymer, polyurethane (PU), which was used as an ultrathin hole blocking and electron injection layer (HB-EIL) on the top of commercially available blue-emitting polymer, polyfluorene. The device with HB-EIL showed a maximum quantum efficiency of 1.7%, while the one without HB-EIL showed an efficiency of 0.6%. They propose that the better performance in PLED with PU layer was due to a well balanced charge injection in emitting layer after the enhanced electron injection due to ionic compound in the insulating PU layer.

  20. Trends in the emissions of Volatile Organic Compounds (VOCs) from light-duty gasoline vehicles tested on chassis dynamometers in Southern California

    NASA Astrophysics Data System (ADS)

    Pang, Yanbo; Fuentes, Mark; Rieger, Paul

    2014-02-01

    We present fleet average VOC emission rate trends for the longest running in-use light-duty gasoline Vehicle Surveillance Program (VSP) in Southern California. Tailpipe emissions data from a limited number of vehicles tested as part of the VSP show that the 2003 fleet average emissions decreased by about 80% for most VOCs relative to the 1995 fleet. Vehicle evaporative emission rates decreased more than 90% for most compounds from the 1999 to the 2003 fleet. Tailpipe benzene-normalized emission rate ratios for most compounds were relatively stable. Evaporative emission rate ratios and weight percentages have changed significantly from the 1999 fleet to the 2003 fleet indicating a significant change in the evaporative emission species patterns. The tailpipe NMHC (Non-Methane HydroCarbon) emission reductions observed between the 1995 fleet and the 2003 fleet likely resulted from the retirement of non-catalyst vehicles in the fleets (49%) and the combined effect of the turn-over of catalyst-equipped vehicles and switch to Phase III gasoline (27%). Our results are consistent with those observed in the Swiss tunnel study. Benzene-normalized emission rate ratios for C2 compounds, aldehydes, and 1,3 butadiene are much higher in tailpipe exhaust than those in evaporative emissions. C4-C5 hydrocarbon ratios in evaporative emissions are much higher than those in exhaust. C8 aromatic compound ratios are comparable for tailpipe and evaporative emissions (hot-soak). Such ratio differences can be used to estimate the relative contributions of vehicle exhaust and evaporative emission to ambient VOCs. The contribution of emissions from malfunctioning vehicles to total fleet emissions increased from 16% to 32% for the 1995 fleet to the 2003 fleet even though the percentage of malfunctioning vehicles in the fleet decreased from 10% to 5%. Most malfunctioning vehicles are vehicles that are at least 10 years old and generally have higher acetylene emission rate ratios. The effective

  1. Characterizing and mitigating emissions of volatile organic compounds from animal feeding operations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

  2. 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.

  3. EMISSIONS OF BIOGENIC OXIDANT AND PM PRECURSORS: VERY HIGH REACTIVITY VOCS AND SURFACE LAYER CHEMISTRY ABOVE FORESTS

    EPA Science Inventory

    Biogenic emissions of volatile organic compounds (VOCs) -- chemicals emitted naturally by the green foliage of a forest, for example -- have been repeatedly shown to be important contributors to ozone pollution levels in many parts of the country. Recently, both the National Rese...

  4. 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.

  5. Estimating human-equivalent no observed adverse-effect levels for VOCs (volatile organic compounds) based on minimal knowledge of physiological parameters. Technical paper

    SciTech Connect

    Overton, J.H.; Jarabek, A.M.

    1989-01-01

    The U.S. EPA advocates the assessment of health-effects data and calculation of inhaled reference doses as benchmark values for gauging systemic toxicity to inhaled gases. The assessment often requires an inter- or intra-species dose extrapolation from no observed adverse effect level (NOAEL) exposure concentrations in animals to human equivalent NOAEL exposure concentrations. To achieve this, a dosimetric extrapolation procedure was developed based on the form or type of equations that describe the uptake and disposition of inhaled volatile organic compounds (VOCs) in physiologically-based pharmacokinetic (PB-PK) models. The procedure assumes allometric scaling of most physiological parameters and that the value of the time-integrated human arterial-blood concentration must be limited to no more than to that of experimental animals. The scaling assumption replaces the need for most parameter values and allows the derivation of a simple formula for dose extrapolation of VOCs that gives equivalent or more-conservative exposure concentrations values than those that would be obtained using a PB-PK model in which scaling was assumed.

  6. 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.

  7. 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

    ... Concrete curing compounds 350 2.9 Concrete curing and sealing compounds 700 5.8 Concrete protective coatings 400 3.3 Concrete surface retarders 780 6.5 Conversion varnish 725 6.0 Dry fog coatings 400...

  8. 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

    ... Concrete curing compounds 350 2.9 Concrete curing and sealing compounds 700 5.8 Concrete protective coatings 400 3.3 Concrete surface retarders 780 6.5 Conversion varnish 725 6.0 Dry fog coatings 400...

  9. 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

    ... Concrete curing compounds 350 2.9 Concrete curing and sealing compounds 700 5.8 Concrete protective coatings 400 3.3 Concrete surface retarders 780 6.5 Conversion varnish 725 6.0 Dry fog coatings 400...

  10. 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

    ... Concrete curing compounds 350 2.9 Concrete curing and sealing compounds 700 5.8 Concrete protective coatings 400 3.3 Concrete surface retarders 780 6.5 Conversion varnish 725 6.0 Dry fog coatings 400...

  11. Volatile organic compound emissions from silage systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  12. Combustion of chlorinated volatile organic compounds (VOCs) using bimetallic chromium-copper supported on modified H-ZSM-5 catalyst.

    PubMed

    Abdullah, Ahmad Zuhairi; Bakar, Mohamad Zailani Abu; Bhatia, Subhash

    2006-02-28

    The paper reports on the performance of chromium or/and copper supported on H-ZSM-5(Si/Al = 240) modified with silicon tetrachloride (Cr1.5/SiCl4-Z, Cu1.5/SiCl4-Z and Cr1.0Cu0.5/SiCl4-Z) as catalysts in the combustion of chlorinated VOCs (Cl-VOCs). A reactor operated at a gas hourly space velocity (GHSV) of 32,000 h(-1), a temperature between 100 and 500 degrees C with 2500 ppm of dichloromethane (DCM), trichloromethane (TCM) and trichloroethylene (TCE) is used for activity studies. The deactivation study is conducted at a GHSV of 3800 h(-1), at 400 degrees C for up to 12 h with a feed concentration of 35,000 ppm. Treatment with silicon tetrachloride improves the chemical resistance of H-ZSM-5 against hydrogen chloride. TCM is more reactive compared to DCM but it produces more by-products due to its high chlorine content. The stabilization of TCE is attributed to resonance effects. Water vapor increases the carbon dioxide yield through its role as hydrolysis agent forming reactive carbocations and acting as hydrogen-supplying agent to suppress chlorine-transfer reactions. The deactivation of Cr1.0Cu0.5/SiCl4-Z is mainly due to the chlorination of its metal species, especially with higher Cl/H feed. Coking is limited, particularly with DCM and TCM. In accordance with the Mars-van Krevelen model, the weakening of overall metal reducibility due to chlorination leads to a loss of catalytic activity. PMID:16310938

  13. Wintertime Secondary Organic Aerosol (SOA) Formation from Oxidation of Volatile Organic Compounds (VOCs) Associated with Oil and Gas Extraction

    NASA Astrophysics Data System (ADS)

    Murphy, S. M.; Soltis, J.; Field, R. A.; Bates, T. S.; Quinn, P.; De Gouw, J. A.; Veres, P. R.; Warneke, C.; Graus, M.; Gilman, J.; Lerner, B. M.; Koss, A.

    2013-12-01

    The Uintah Basin is located in a lightly populated area of Northeastern Utah near Dinosaur National Monument. Oil and gas extraction activities in the basin have dramatically increased in recent years due to the application of hydraulic fracturing. The Uintah Basin has experienced numerous high-ozone events during the past several winters with concentrations often exceeding 100 ppb. PM 2.5 monitoring by the city of Vernal, located at the edge of the basin, have shown wintertime concentrations in excess of the EPA 8-hour national standard, though the source and composition of particulates during these events is unclear. The Energy and Environment - Uintah Basin Winter Ozone Study (E&E UBWOS) was conducted during the winters of 2012 and 2013. During the study, intensive measurements of aerosol composition and speciated VOCs were made at a monitoring site near oil and gas extraction activities. Organic aerosol was found to be a major component of PM 2.5 and organic aerosol formation was highly correlated with the production of secondary VOC's. This correlation suggests that the organic aerosol is secondary in nature even though O:C ratios suggest a less oxidized aerosol than often observed in summertime SOA. The ozone levels and organic aerosol mass during 2012 were much lower than those observed in 2013. Calculations of the aerosol yield during both years will be presented along with an analysis of how well observed yields match predictions based on smog-chamber data. The potential for additional aerosol formation in the system will also be discussed.

  14. Challenges and solutions for biofiltration of hydrophobic volatile organic compounds.

    PubMed

    Cheng, Yan; He, Huijun; Yang, Chunping; Zeng, Guangming; Li, Xiang; Chen, Hong; Yu, Guanlong

    2016-11-01

    Volatile organic compounds (VOCs) emitted to the environment highly probably result in ecological and health risks. Many biotechnologies for waste gases containing hydrophobic VOCs have been developed in recent years. However, these biological processes usually exhibit poor removal performances for hydrophobic VOCs due to the low bioavailability. This review presents an overview of enhanced removal of hydrophobic VOCs in biofilters. Mechanisms and problems relevant to the biological removal of hydrophobic VOCs are reviewed, and then solutions including the addition of surfactants, application of fungal biocatalysts, biofiltration with pretreatment, innovative bioreactors and utilization of hydrophilic compounds are discussed in detail. Future research needs are also proposed. This review provides new insights into hydrophobic VOC removal by biofiltration. PMID:27374790

  15. 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.

  16. 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.

  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. PMID:23334204

  18. 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

  19. 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

  20. Analysis of volatile organic compounds (VOCs) in A/M Area Crouch Branch (Cretaceous) Aquifer characterization samples: 1993

    SciTech Connect

    Looney, B.B.; Haselow, J.S.; Keenan, M.A.; Van Pelt, R.; Eddy-Dilek, C.A.; Rossabi, J.; Simmons, J.L.

    1993-12-06

    Samples were collected during the A/M Area Crouch Branch (Cretaceous) Aquifer Characterization (Phase I) Program. The samples were analyzed for chlorinated VOCs by the Savannah River Technology Center (SRTC) and MicroSeeps Ltd. All samples were sealed in the field immediately upon retrieval of the core and subsampling. A total of 113 samples locations were selected for analysis. The Environmental Sciences Section (ESS) of SRTC analyzed all locations in duplicate (226 samples). MicroSeeps Ltd was selected as the quality assurance (QA) check laboratory. MicroSeeps Ltd analyzed 40 locations with 4 duplicates (44 samples). The samples were collected from seven boreholes in A/M Area in the interval from 200 feet deep to the total depth of the boring (360 feet deep nominal); samples were collected every 10 feet within this interval. The sampling zone corresponds approximately to the Crouch Branch Aquifer in A/M Area. The overall A/M Area Crouch Branch Aquifer characterization objectives, a brief description of A/M Area geology and hydrology, and the sample locations, field notes, driller lithologic logs, and required procedural documentation are presented in WSRC (1993).

  1. 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.

  2. 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.

  3. 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

    2015-12-01

    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. PMID:26670078

  4. DEVELOPMENT OF A SYSTEMATIC APPROACH TO ACCURATELY MEASURE TRACE LEVELS OF VOLATILE ORGANIC COMPOUNDS (VOCS) IN SOIL AND SEDIMENT CONTAINING HIGH MOISTURE TO MEET THE EPA'S RISK ASSESSMENT NEEDS

    EPA Science Inventory

    A majority of the contaminated sites within the United States contain volatile organic compounds (VOCs), either as industrial chlorinated solvents or petroleum products commonly referred to as BTEX (benzene, toluene, ethyl benzene, and xylene). The present EPA methods for low le...

  5. REDUCING UNCERTAINTY IN AIR TOXICS RISK ASSESSMENT: A MECHANISTIC EXPOSURE-DOSE-RESPONSE (EDR) MODEL FOR ASSESSING THE ACUTE NEUROTOXICITY OF VOLATILE ORGANIC COMPOUNDS (VOCS) BASED UPON A RECEPTOR-MEDIATED MODE OF ACTION

    EPA Science Inventory

    SUMMARY: The major accomplishment of NTD’s air toxics program is the development of an exposure-dose- response model for acute exposure to volatile organic compounds (VOCs), based on momentary brain concentration as the dose metric associated with acute neurological impairments...

  6. 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.

  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. Detection and localization of particle-emitting sources with compound-eye inspired detector arrays

    NASA Astrophysics Data System (ADS)

    Liu, Zhi

    2007-08-01

    We develop methods to detect and localize particle-emitting sources using detector arrays that are inspired by biological compound eyes. The sources of interest may be optical, nuclear, or cosmic; they emit particles such as visible photons, neutrons, protons, or charged particles. Our results may have wide applications to artificial vision, which can be important in robotics (robot vision) or medicine (e.g., artificial eyes for the blind); security, where the detection of nuclear materials is needed; or astronomy. This dissertation consists of three parts. First, we detect a far-field particle source using two directional detector arrays: cubic and spherical. We propose a mean-difference test (MDT) detector, analyze its statistical performance, and show that the MDT has a number of advantages over the generalized likelihood- ratio test (GLRT). Second, we localize the source by proposing a novel biologically inspired detector array, whose configuration generalizes the compound eye of insects. This array combines the advantages of compound eyes (e.g., large field-of-view) and human eyes (e.g., high angular resolution). Based on a statistical model of the array measurements, we analyze the array performance by computing the Cramérao bound (CRB) on the error in estimating the source direction. We also derive lower bounds on the mean-square angular error (MSAE) of the source localization and investigate the MSAE of two source- direction estimators. Numerical examples, including the optimal array design, are presented to further illustrate the array performance. Third, we derive a statistical angular resolution limit (ARL) on resolving two closely spaced point sources in a three-dimensional frame, which is applicable to various measurement models (e.g., radar, sonar, or astronomy). Using the asymptotic analysis of the GLRT, we derive the ARL with constraints on the probabilities of false alarm and detection. Our results give explicit analytical expression for the ARL

  9. 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.

  10. MSA for VOC removal

    SciTech Connect

    Lighty, C.W. ); Drago, J.A. )

    1993-03-01

    This article describes what may be the first large-scale application of its type; mechanical surface aeration--usually used in wastewater treatment--is removing volatile organic compounds from potable ground water at a treatment plant in Santa Monica, Calif. Discovery of trace amounts of volatile organic compounds (VOCs) in Santa Monica, Calif's municipal water wells cut available ground-water supplies and increased dependence on expensive imported surface water. With California's extended drought threatening those supplies as well, the search began for a cost-effective way to remove the VOCs and restore the lost ground-water resources. The city retained Kennedy/Jenks Consultants, San Francisco, in 1989 to plan and design an expansion of the Arcadia Water Treatment Plant that included treatment for the voc trichloroethylene (TCE), an industrial solvent and suspected carcinogen. A common solution would have been air stripping, using packed tower aeration (PTA), but several special conditions led us to take a different approach. The plant occupies a city block in densely populated west Los Angeles along the affluent Wilshire Boulevard corridor, and is surrounded by high-rise office buildings, extensive commercial and residential development, schools, and a hospital. It was very important that they minimize the aesthetic and environmental impacts of the plant expansion. At the same time, capital and operating costs had to be kept within reasonable limits. The authors were able to address these concerns and achieve the treatment objectives by using mechanical surface aeration (MSA) technology, which allowed us to hide the aeration process within an existing 5 million gal. reservoir. This project is one of the first large-scale applications of MSA technology to remove VOCs. The process could be used by other plants in heavily populated areas where space is limited and where aesthetics, noise and public health are sensitive issues.

  11. 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.

  12. 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. PMID:23139201

  13. 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.

  14. 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.

  15. 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

  16. 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). PMID:22186871

  17. 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.

  18. Source reduction of VOC and hazardous organic emissions from wood furniture coatings

    SciTech Connect

    Huang, E.W.; McCrillis, R.C.

    1996-12-31

    Under US EPA sponsorship, AeroVironment, Inc. and Adhesives Coating Co. are teaming up to develop and demonstrate a wood furniture coating system containing no volatile organic compounds (VOCs) and no hazardous air pollutants (HAPs), making it less hazardous to use, and emitting no detectable VOCs and HAPs during curing, therefore contributing significantly to emission reduction. Earlier work on a new topcoat showed excellent performance characteristics in terms of adhesion, gloss value, dry time, hardness, organic solvents content, and chemical/stain resistance. The VOC contents of both the clear topcoat and the white pigmented topcoat were less than 10 g/L, the detection list of the test method (EPA Method 24). This coating`s performance and properties compared favorably with those of other low-VOC waterborne coatings. Currently, low-/no-VOC stain and sealer wood coatings are being developed so that a complete low-/no-VOC wood coating system will be available for public use. The compatibility of coating components (a stain and sealer) to go with the topcoat is currently being evaluated. The complete system will be demonstrated at several furniture plants. A marketing plan of the developed products is part of this demonstration project.

  19. Speciation of volatile organic compounds from poultry production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  20. VOC PREVENTION OPTIONS FOR SURFACE COATING

    EPA Science Inventory

    The paper discusses some of the volatile organic compound (VOC) prevention options for surface coating. Most small surface coating industries are considered to be stationary area sources. Although stationary area sources may account for as much as 50% of national VOC emissions, t...

  1. 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...

  2. MEASUREMENT OF VOCS FROM THE TAMS NETWORK

    EPA Science Inventory

    Target volatile organic compounds (VOCS) were measured at a network of urban air monitoring locations in Boston, Chicago, Houston, and the Seattle/Tacoma area. ollowing a pilot-scale field evaluation of available techniques for determining concentrations of VOCs in ambient air, a...

  3. 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...

  4. The adsorption and reaction of halogenated volatile organic compounds (VOC's) on metal oxides. 1998 annual progress report

    SciTech Connect

    Lunsford, J.; Goodman, D.W.; Haw, J.F.

    1998-06-01

    'The goal of the research is to elucidate the properties of the materials responsible for the activation of halocarbons and the nature of the intermediates formed in the dissociative adsorption of this class of compounds. This information is essential for interpreting and predicting stoichiometric and catalytic pathways for the safe destruction of halocarbon pollutants. The specific objectives are: (1) to study the adsorption and reactivity of chloromethanes and chloroethanes on metal oxides; (2) to identify the reaction intermediates using spectroscopic methods; and (3) to develop kinetic models for the reaction of these halocarbons with oxide surfaces. This report summarizes work after 20 months of a 36-month project. Emphasis has been placed understanding the surfaces phases, as well as the bulk phases that are present during the reactions of chlorinated hydrocarbons with strongly basic metal oxides. Most of the research has been carried out with carbon tetrachloride.'

  5. 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

  6. The role of skin absorption as a route of exposure for volatile organic compounds (VOCs) in drinking water

    SciTech Connect

    Brown, H.S.; Bishop, D.R.; Rowan, C.A.

    1984-05-01

    Assessments of drinking water safety rely on the assumption that ingestion represents the principal route of exposure. A review of the experimental literature revealed that skin penetration rates for solvents are remarkably high, and that the stratum corneum is a less effective barrier to penetration than traditionally assumed. Based on published skin absorption rates, we used Fick's law (Jos . Kop delta Cos) to determine permeability constants for selected compounds. We then calculated dose per kilogram for nine different exposure situations and compared this to the oral dose per kilogram. We found that skin absorption contributed from 29-91 per cent of the total dose, averaging 64 per cent. Dose per kilogram body weight ranged from .0002 mg/kg-.18 mg/kg, with an average of .03 mg/kg. In weak aqueous solutions, flux of the solute is directly proportional to concentration. Laboratory approaches differ markedly from environmental exposures and can underestimate absorption. We conclude that skin absorption of contaminants in drinking water has been underestimated and that ingestion may not constitute the sole or even primary route of exposure.

  7. 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. PMID:21305886

  8. Identification of volatile compounds emitted by Artemisia ordosica (Artemisia, Asteraceae) and changes due to mechanical damage and weevil infestation.

    PubMed

    Zhang, Hui; Zhou, Dayong; Luo, Youqing; Wang, Jinlin; Zong, Shixiang

    2013-01-01

    Volatiles emitted by healthy, mechanically damaged, and weevil-infested Artemisia ordosica (Asteraceae) were obtained through a dynamic headspace method and analysed by automatic thermal desorption/gas chromatography/mass spectrometry (ATD/GC/MS). Twenty-eight compounds in all were identified, and the qualitative as well as quantitative differences were compared. The green leaf volatiles 2-hexenal, (Z)-3-hexen-1-ol, 2-hexen-1-ol, 1-hexanol, and (Z)-3-hexen-1-ol acetate were present in all of the damaged plants, but in relatively lower portions when plants were infested by the weevil Adosopius sp., while the terpenoids alpha-copaene, beta-cedrene, and (E,E)-alpha-farnesene and the ester methyl salicylate were only present in weevil-damaged plants. The volatiles from healthy and weevil-infested leaves were dominated by D-limonene, whereas mechanically damaged leaves emitted beta-pinene as the dominant compound. PMID:24066517

  9. Investigation of two-photon absorption properties in new A-D-A compounds emitting blue and yellow fluorescence

    NASA Astrophysics Data System (ADS)

    Jin, Fan; Cai, Zhi-Bin; Huang, Jiu-Qiang; Li, Sheng-Li; Tian, Yu-Peng

    2015-08-01

    Three new acceptor-donor-acceptor compounds (LBQ, DBQ, BYQ) were synthesized and characterized by infrared, hydrogen nuclear magnetic resonance, mass spectrometry and elemental analysis. Their photophysical properties were investigated including linear absorption, single-photon excited fluorescence, fluorescence quantum yield and two-photon absorption. These compounds in CH2Cl2 exhibit good fluorescence quantum yield which are 0.36, 0.26, and 0.25 and the largest two-photon absorption cross-section which are 48, 36, and 181 GM respectively. Under the excitation of Ti: sapphire laser with a pulse width of 140 fs, LBQ and DBQ emit blue two-photon excited fluorescence (TPEF), while BYQ emits bright yellow TPEF. BYQ has a good solubility in water and the σ can be as large as 130 GM, so it shows promising applications in many pharmaceutical and biological fields.

  10. 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.

  11. 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

  12. 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

  13. 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 ...

  14. 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.

  15. 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.

  16. The use of proton transfer mass spectrometry to characterize VOC concentrations within a deciduous forest

    NASA Astrophysics Data System (ADS)

    Ammann, C.; Spirig, C.; Neftel, A.; Schaub, A.; Komenda, M.

    2003-04-01

    Proton Transfer Mass Spectrometry (PTR-MS) has become an important technique for fast measurements of biogenic volatile organic compounds (VOC). As part of the German ECHO project (Emission and chemical transformation of biogenic volatile organic compounds), a PTR-MS instrument was calibrated and applied for a range of VOC including isoprene, sum of monoterpenes, methanol, acetaldehyde, acetone and others. During the first ECHO field campaign in June and July 2002 continuous four-level concentration profiles were measured within and above a mixed deciduous forest stand on an hourly basis. VOC concentrations obtained by PTR-MS agreed reasonably well with parallel gas chromatography measurements. The spatial and temporal distribution of the biogenic VOC such as monoterpenes and isoprene generally reflect the local source with maximum concentrations during daytime within the canopy. Gradients of monoterpenes at the canopy top were more consistent than those of isoprene, which is attributed to the inhomogeneous emission pattern, i.e. the direct surrounding of the measurement tower was dominated by monoterpene-emitting trees (beeches) whereas the dominant isoprene emitters (oaks) were mainly located further upwind. Acetone and the aromatic compounds frequently showed high nighttime concentration peaks reflecting advection of anthropogenic emissions from outside the forest.

  17. 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. PMID:27112551

  18. Electronic and optical properties of novel carbazole-based donor-acceptor compounds for applications in blue-emitting organic light-emitting diodes

    NASA Astrophysics Data System (ADS)

    Legaspi, Christian M.; Stubbs, Regan E.; Yaron, David J.; Peteanu, Linda A.; Sfeir, Matthew Y.; Kemboi, Abraham; Picker, Jesse; Fossum, Eric

    2015-08-01

    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.

  19. Characterization of multifunctional organic nitrates and other VOC during BEARPEX 2007

    NASA Astrophysics Data System (ADS)

    Atlas, E.; Hynes, T.; Bauer, D.; Ren, X.

    2008-12-01

    There is an interest in the role of organic nitrates during the oxidation of reactive hydrocarbons, especially isoprene and terpenes emitted from vegetation. These biogenic VOC are highly reactive and laboratory studies have shown that they can form organic nitrates in high yield during oxidation by OH and NO3 radicals. These high yields can have a significant impact on radical budgets, ozone formation, nitrogen cycling, and possibly aerosol formation. However, with few exceptions, the actual organic nitrate products from biogenic VOC have not been identified, either in the lab or in the field. Measurement of 'Total Alkyl Nitrate' by a thermal dissociation laser-induced fluorescence (TD-LIF) technique (Cohen et al., UC-Berk) suggests the presence of significant organic nitrate that has not been identified. Presumably the components of this measurement are multifunctional nitrates that are difficult to measure with conventional techniques. We have used a micro-charcoal adsorption technique (and evaluated other sorbents) to measure a range of organic nitrates and other higher molecular weight VOC in the Blodgett Forest during BEARPEX 2007. The goal of this study was to characterize the range and types of organic nitrates in the forest environment and provide some preliminary estimates of the magnitude of the multifunctional nitrates present. The analytical technique was also used to characterize other higher molecular weight VOC in the forest environment. In addition to terpene compounds, a large number and range of methoxylated or methylated VOC were identified.

  20. 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.

  1. 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.

  2. Characterization and determination of the odorous charge in the indoor air of a waste treatment facility through the evaluation of volatile organic compounds (VOCs) using TD-GC/MS.

    PubMed

    Gallego, E; Roca, F J; Perales, J F; Sánchez, G; Esplugas, P

    2012-12-01

    Municipal solid waste treatment facilities are generally faced with odorous nuisance problems. Characterizing and determining the odorous charge of indoor air through odour units (OU) is an advantageous approach to evaluate indoor air quality and discomfort. The assessment of the OU can be done through the determination of volatile organic compounds (VOCs) concentrations and the knowledge of their odour thresholds. The evaluation of the presented methodology was done in a mechanical-biological waste treatment plant with a processing capacity of 245.000 tons year(-1) of municipal residues. The sampling was carried out in five indoor selected locations of the plant (Platform of Rotating Biostabilizers, Shipping warehouse, Composting tunnels, Digest centrifugals, and Humid pre-treatment) during the month of July 2011. VOC and volatile sulphur compounds (VSCs) were sampled using multi-sorbent bed (Carbotrap, Carbopack X, Carboxen 569) and Tenax TA tubes, respectively, with SKC AirCheck 2000 pumps. The analysis was performed by automatic thermal desorption (ATD) coupled with a capillary gas chromatography (GC)/mass spectrometry detector (MSD). One hundred and thirty chemical compounds were determined qualitatively in all the studied points (mainly alkanes, aromatic hydrocarbons, alcohols, aldehydes, esters, and terpenes), from which 86 were quantified due to their odorous characteristics as well as their potentiality of having negative health effects. The application of the present methodology in a municipal solid waste treatment facility has proven to be useful in order to determine which type of VOC contribute substantially to the indoor air odorous charge, and thus it can be a helpful method to prevent the generation of these compounds during the treatment process, as well as to find a solution in order to suppress them. PMID:22883687

  3. Chamber assessment of formaldehyde and VOC emissions from wood-based panels.

    PubMed

    Brown, S K

    1999-09-01

    Volatile organic emissions from particleboard, medium density fibreboard (MDF) and office furniture have been measured in dynamic environmental chambers, both small and room-sized. Characterisation of product emission properties in small chambers was possible when inter- and intra-sheet variations were considered. Formaldehyde emission factors for all products were approximately double European low-emission specifications and did not decay to the latter for several months. Long-term emission behaviour could not be predicted from short-term measurements. Volatile organic compounds (VOC) emissions were low for the MDF product, higher for particleboard, and highest for laminated office furniture. The compounds emitted differed from those reported in other countries. VOC emissions from the sheet products decreased more quickly than formaldehyde, reaching low levels within two weeks, except for MDF which was found to become a low-level source of hexanal after several months. PMID:10439559

  4. 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

  5. Singlet harvesting with brightly emitting Cu(I) and metal-free organic compounds

    NASA Astrophysics Data System (ADS)

    Yersin, Hartmut; Czerwieniec, Rafal; Hupfer, Alexander

    2012-06-01

    In an electroluminescent excitation, singlet and triplet excitons are generated. In this contribution it is proposed to harvest all excitons in an efficiently emitting singlet state by use of molecules which exhibit distinct thermally activated delayed fluorescence at T = 300K. Highly attractive examples, comprising Cu(I) complexes and the metal-free acridine orange, are presented and discussed with respect to their photophysical properties.

  6. 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

  7. Contrasting winter and summer VOC mixing ratios at a forest site in the Western Mediterranean Basin: the effect of local biogenic emissions

    NASA Astrophysics Data System (ADS)

    Seco, R.; Peñuelas, J.; Filella, I.; Llusià, J.; Molowny-Horas, R.; Schallhart, S.; Metzger, A.; Müller, M.; Hansel, A.

    2011-12-01

    Atmospheric volatile organic compounds (VOCs) are involved in ozone and aerosol generation, thus having implications for air quality and climate. VOCs and their emissions by vegetation also have important ecological roles as they can protect plants from stresses and act as communication cues between plants and between plants and animals. In spite of these key environmental and biological roles, the reports on seasonal and daily VOC mixing ratios in the literature for Mediterranean natural environments are scarce. We conducted seasonal (winter and summer) measurements of VOC mixing ratios in an elevated (720 m a.s.l.) holm oak Mediterranean forest site near the metropolitan area of Barcelona (NE Iberian Peninsula). Methanol was the most abundant compound among all the VOCs measured in both seasons. While aromatic VOCs showed almost no seasonal variability, short-chain oxygenated VOCs presented higher mixing ratios in summer, presumably due to greater emission by vegetation and increased photochemistry, both enhanced by the high temperatures and solar radiation in summer. Isoprenoid VOCs showed the biggest seasonal change in mixing ratios: they increased by one order of magnitude in summer, as a result of the vegetation's greater physiological activity and emission rates. The maximum diurnal concentrations of ozone increased in summer too, most likely due to more intense photochemical activity and the higher levels of VOCs in the air. The daily variation of VOC mixing ratios was mainly governed by the wind regime of the mountain, as the majority of the VOC species analyzed followed a very similar diel cycle. Mountain and sea breezes that develop after sunrise advect polluted air masses to the mountain. These polluted air masses had previously passed over the urban and industrial areas surrounding the Barcelona metropolitan area, where they were enriched in NOx and in VOCs of biotic and abiotic origin. Moreover, these polluted air masses receive additional biogenic

  8. Contrasting winter and summer VOC mixing ratios at a forest site in the Western Mediterranean Basin: the effect of local biogenic emissions

    NASA Astrophysics Data System (ADS)

    Seco, R.; Peñuelas, J.; Filella, I.; Llusià, J.; Molowny-Horas, R.; Schallhart, S.; Metzger, A.; Müller, M.; Hansel, A.

    2011-07-01

    Atmospheric volatile organic compounds (VOCs) are involved in ozone and aerosol generation, thus having implications for air quality and climate. VOCs and their emissions by vegetation also have important ecological roles as they can protect plants from stresses and act as communication cues between plants and between plants and animals. In spite of these key environmental and biological roles, the reports on seasonal and daily VOC mixing ratios in the literature for Mediterranean natural environments are scarce. We conducted seasonal (winter and summer) measurements of VOC mixing ratios in an elevated (720 m a.s.l.) holm oak Mediterranean forest site near the metropolitan area of Barcelona (NE Iberian peninsula). Methanol was the most abundant compound among all the VOCs measured in both seasons. While aromatic VOCs showed almost no seasonal variability, short-chain oxygenated VOCs presented higher mixing ratios in summer, presumably due to greater emission by vegetation and increased photochemistry, both enhanced by the high temperatures and solar radiation in summer. Isoprenoid VOCs showed the biggest seasonal change in mixing ratios: they increased by one order of magnitude in summer, as a result of the vegetation's greater physiological activity and emission rates. The maximum diurnal concentrations of ozone increased in summer too, most likely due to more intense photochemical activity and the higher levels of VOCs in the air. The daily variation of VOC mixing ratios was mainly governed by the wind regime of the mountain, as the majority of the VOC species analyzed followed a very similar diel cycle. Mountain and sea breezes that develop after sunrise advect polluted air masses to the mountain. These polluted air masses had previously passed over the urban and industrial areas surrounding the Barcelona metropolitan area, where they were enriched in NOx and in VOCs of biotic and abiotic origin. Moreover, these polluted air masses receive additional biogenic

  9. 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.

  10. Biogenic and Anthropogenic VOC Emissions over the Central and Southern U.S.: Results from Recent Airborne Field Campaigns (Invited)

    NASA Astrophysics Data System (ADS)

    Hornbrook, R. S.; Apel, E. C.; Riemer, D. D.; Hills, A. J.; Kaser, L.; Emmons, L. K.; Lamarque, J.; Blake, N. J.; Simpson, I. J.; Blake, D. R.; Karl, T.; Yuan, B.

    2013-12-01

    Over the last two years, the NCAR Trace Organic Gas Analyzer (TOGA), capable of quantifying over 50 individual gas-phase volatile organic compounds (VOCs), was deployed on two airborne field campaigns with flights over the central and southeast United States: Deep Convective Cloud and Chemistry (DC3), and Nitrogen, Oxidants, Mercury and Aerosol Distributions, Sources and Sinks (NOMADSS). These studies provided opportunities to sample air masses dominated by individual emissions sources, including biomass burning, oil and gas extraction, biogenic activity, and marine emissions, as well as the impact of convection on recently emitted trace gases. Using observations of biogenic VOCs, including speciated monoterpenes, we will compare our findings with NCAR CESM CAM-chem model simulations using the MEGAN emissions inventory. Likewise, we will contrast our observations of anthropogenic VOCs over the continental U.S. to model simulations with anthropogenic inventories (e.g., NEI, EDGAR).

  11. 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.

  12. Modeling emissions of volatile organic compounds from silage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  13. 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.

  14. 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. PMID:26498819

  15. 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. PMID:26117814

  16. 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. PMID:26398629

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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. PMID:15015582

  4. 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.

  5. 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. PMID:21376441

  6. Biofilters remove VOCs from stack gases

    SciTech Connect

    Not Available

    1993-10-01

    Weyerhaeuser's strandboard plant in Grayling, Mich., is using biofiltration to remove volatile organic compounds (VOCs) at the site. Primary constituents in the Weyerhaeuser stack gases are alcohols, aldehydes, organic acids, benzene and toluene. The alternative to biofiltration is incineration, but because the concentration of VOCs in the stack gases is so dilute, natural gas would be required. Incineration would be costly, and could introduce pollution problems by generating excess carbon dioxide (CO[sub 2]) and possibly nitrogen oxides. Two pilot biofilters, each about 20ft by 100ft in area, with 4-ft thick media of bark and ground trim ends, are using naturally occurring bacteria to destroy VOCs emanating from a wood panel press and a wood flake dryer. The press offgas biofilter, activated February 1993, had risen to 93% efficiency in removing VOCs by mid-May. The flake dryer exhaust biofilter, placed in service in April, already was more than 80% efficient.

  7. 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 ...

  8. USE OF THE FUNGUS EXOPHIALA LECANII-CORNI TO DEGRADE A MIXTURE OF VOCS

    EPA Science Inventory

    Stricter regulations on volatile organic compounds (VOCs) and hazardous air pollutants (HAPs) have increased the demand for more efficient abatement technologies. One promising technology for removing VOCs from polluted gas streams is biofiltration, a process in which contaminate...

  9. 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.

  10. 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

  11. 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.

  12. 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.

  13. 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.

  14. Identification of estrogenic compounds emitted from the combustion of computer printed circuit boards in electronic waste.

    PubMed

    Owens, Clyde V; Lambright, Christy; Bobseine, Kathy; Ryan, Bryce; Gray, L Earl; Gullett, Brian K; Wilson, Vickie S

    2007-12-15

    Rapid changes in technology have brought about a surge in demand for electronic equipment. Many of these products contain brominated flame-retardants (BFRs) as additives to decrease the rate of combustion, raising concerns about their toxicological risk. In our study, emissions from the combustion of computer-printed circuit boards were evaluated in the T47D-KBluc estrogen-responsive cell line at a series of concentrations. There was significant activity from the emission extract when compared to the positive control, 0.1 nM estradiol. After HPLC fractionation, GC/MS identified ten chemicals which included bisphenol A; the brominated derivates mono-, di-, and tribisphenol, triphenyl phosphate, triphenyl phosphine oxide, 4'-bromo-[1,1'-biphenyl]-4-ol,3,5-dibromo-4-hydroxybiphenyl,3,5-dibromo-2-hydroxybiphenyl, and the oxygenated polyaromatic hydrocarbon benzanthrone. Commercially available samples of these ten compounds were tested. The compound 4'-bromo-[1,1'-biphenyl]-4-ol resulted in dose-dependent significant increases for luciferase activity at concentrations ranging from 0.1 to 10 microM in the T47D-KBluc assay. The chemical also demonstrated an affinity for binding to the estrogen receptor (ER) with an IC50 of 2 x 10(-7) M. To determine the uterotrophic activity, three doses (50, 100, and 200 mg/kg/day) of 4'-bromo-[1,1'-biphenyl]-4-ol were administered to adult ovariectomized Long-Evans rats for 3 days. Treatment of the animals with 200 mg/ kg/day showed an increase in uterine weight Hence one new chemical, released by burning of electrical wastes, was identified which displays estrogenic activity both in vitro and in vivo. However, it was about 1000-fold less potent than ethynyl estradiol. PMID:18200886

  15. 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

  16. 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

  17. Light emitting diodes from MOVPE-grown p- and n-doped II VI compounds

    NASA Astrophysics Data System (ADS)

    Gebhardt, W.; Hahn, B.; Stanzl, H.; Deufel, M.

    1996-02-01

    A critical review is given of the present state, the problems and the prospects of MOVPE-growth of II-VI LEDs. It is shown that MOVPE-growth on (001)GaAs substrates occurs preferentially in a three-dimensional growth mode independent of substrate preparation. ZnS xSe 1 - x grows in good quality over the whole range of composition x. Good quality of Zn xCd 1 - xSe was only obtained for low Cd-concentrations. Improvements can be expected from the use of new precursors. The n-doping of ZnSe and ZnS xSe 1 - x presents no problem when n-butylchloride is used. Carrier concentrations can be as high as n ≥ 10 18. Various nitrogen compounds have been used to achieve p-doping of ZnSe by MOVPE. We show that quite large concentrations of nitrogen can be incorporated by photoassisted MOVPE with phenylhydrazine as precursor. The nitrogen doped samples are usually highly compensated independent from the special doping procedure. Proper annealing can activate at least part of the incorporated nitrogen. The preparation of appropriate diode structures presents no special problems, however their room temperature (RT) luminescence efficiency is still low but may be considerably improved with increasing purity of precursors.

  18. 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

  19. VOC emissions from beech, birch, and oak

    NASA Astrophysics Data System (ADS)

    Wildt, J.; Folkers, A.; Koch, N.; Kleist, E.

    2003-04-01

    VOC emissions from beech (Fagus sylvatica), birch (Betula pendula), and oak (Quercus robur) were studied in continuously stirred tank reactors. Oak emitted nearly exclusively isoprene. The dependence of these isoprene emissions on temperature and photosynthetic radiation (PAR) could quite well be described with existing algorithms and the emission factors were fairly constant. Beech and birch emitted mainly short chained oxygenated VOC and monoterpenes. Temperature and PAR dependence of monoterpene emissions were superimposed by a slow frequency modulation. Hence, descriptions of these emissions with existing algorithms were not successful. Moreover, in some cases the emission pattern switched drastically. For birch it was observed that the plant switched from a sesquiterpene emitter to a monoterpene emitter. emission pattern plants. Emissions of ethanol, acetaldehyde, and methanol were not affected by PAR. Here, the emission factors are determined by other factors not included in existing algorithms.

  20. Sorptive interactions between VOCs and indoor materials.

    PubMed

    Won, D; Corsi, R L; Rynes, M

    2001-12-01

    This study was carried out using various materials (carpet, gypsum board, upholstery, vinyl and wood flooring, acoustic tiles, and fruit) that were exposed to eight gaseous volatile organic compounds (VOCs) (isopropanol, MTBE, cyclohexane, toluene, ethylbenzene, tetrachloroethene, 1,2-dichlorobenzene, and 1,2,4-trichlorobenzene) in electro-polished stainless-steel chambers. Dynamic responses in VOC concentrations were used to determine linear adsorption and desorption rate coefficients and equilibrium partition coefficients. A linear adsorption/desorption model was used to effectively describe the interactions between VOCs and indoor surface materials for short-term source events (10 h). Relationships between sorption parameters and chemical vapor pressure and the octanol-air partition coefficient were observed. Carpet was identified as the most significant sorptive sink for non-polar VOCs. Virgin gypsum board was observed to be a significant sink for highly polar VOCs. Sorptive interactions between non-polar VOCs and indoor materials were not affected by variations in relative humidity. However, increases in relative humidity were observed to increase the degree of sorption of isopropanol to carpet. PMID:11761600

  1. Phosphorescence versus thermally activated delayed fluorescence. Controlling singlet-triplet splitting in brightly emitting and sublimable Cu(I) compounds.

    PubMed

    Leitl, Markus J; Krylova, Valentina A; Djurovich, Peter I; Thompson, Mark E; Yersin, Hartmut

    2014-11-12

    Photophysical properties of two highly emissive three-coordinate Cu(I) complexes, (IPr)Cu(py2-BMe2) (1) and (Bzl-3,5Me)Cu(py2-BMe2) (2), with two different N-heterocyclic (NHC) ligands were investigated in detail (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene; Bzl-3,5Me = 1,3-bis(3,5-dimethylphenyl)-1H-benzo[d]imidazol-2-ylidene; py2-BMe2 = di(2-pyridyl)dimethylborate). The compounds exhibit remarkably high emission quantum yields of more than 70% in the powder phase. Despite similar chemical structures of both complexes, only compound 1 exhibits thermally activated delayed blue fluorescence (TADF), whereas compound 2 shows a pure, yellow phosphorescence. This behavior is related to the torsion angles between the two ligands. Changing this angle has a huge impact on the energy splitting between the first excited singlet state S1 and triplet state T1 and therefore on the TADF properties. In addition, it was found that, in both compounds, spin-orbit coupling (SOC) is particularly effective compared to other Cu(I) complexes. This is reflected in short emission decay times of the triplet states of only 34 μs (1) and 21 μs (2), respectively, as well as in the zero-field splittings of the triplet states amounting to 4 cm(-1) (0.5 meV) for 1 and 5 cm(-1) (0.6 meV) for 2. Accordingly, at ambient temperature, compound 1 exhibits two radiative decay paths which are thermally equilibrated: one via the S1 state as TADF path (62%) and one via the T1 state as phosphorescence path (38%). Thus, if this material is applied in an organic light-emitting diode, the generated excitons are harvested mainly in the singlet state, but to a significant portion also in the triplet state. This novel mechanism based on two separate radiative decay paths reduces the overall emission decay time distinctly. PMID:25260042

  2. 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.

  3. Characterization and measurement of VOC emissions from silage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

  4. 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.

  5. 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 ...

  6. 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.

  7. 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...

  8. 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. PMID:26489914

  9. Reduction of VOCs during pressing of OSB with the use of chemical additives

    SciTech Connect

    Williams, L.S.; McGinnis, G.D.; Kleinheinz, G.T.; Niemi, B.A.; Flicker, T.M.

    1999-07-01

    As air pollution regulations continue to become increasingly stringent, it is critical for the wood composite industry to develop more efficient and economical methods for handling air pollutant emissions. Technologies currently being used for end of pipeline control are often expensive to install and operate; therefore, more cost-effective methods of reduction are necessary. This project was undertaken to determine the feasibility of using various chemical compounds during pressing or drying of wood particles to minimize/reduce volatile organic compound (VOC) emissions from wood composite plants. This study was designed specifically to develop chemical treatment systems, which would reduce VOCs in air emitted from presses and dryers during the oriented strandboard (OSB) manufacturing process. A series of acids, bases, oxidizing agents and nucleophiles were evaluated in this study. The initial model waste stream consisted of furfural and a series of mono-terpenes. The first year results indicated that several of the chemicals did destroy the VOCs; in some cases destruction was observed as high as 75%. The first year of this study was conducted in the laboratory, while the second and third years will combine laboratory studies and OSB plant studies.

  10. 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...

  11. 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...

  12. 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.

  13. 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

    2016-01-01

    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. PMID:27571054

  14. Socioeconomic and personal behavioral factors affecting children's exposure to VOCs in urban areas in Korea.

    PubMed

    Byun, Hyaejeong; Ryu, Kyongnam; Jang, Kyungjo; Bae, Hyunjoo; Kim, Dongjin; Shin, Hosung; Chu, Jangmin; Yoon, Chungsik

    2010-02-01

    Volatile organic compounds (VOCs) are known to cause adverse health effects. We investigated the relationships between children's VOC exposure and socioeconomic and human activity factors with passive personal samplers, questionnaires, and time-activity diaries (TAD). Statistical analyses were conducted using SAS 9.1, and the results were organized using SigmaPlot 8.0 software. Chemicals such as benzene, toluene, 2-butanone, ethylbenzene, xylene, chloroform, n-hexane, heptane, and some kinds of decanes, which are known to adversely affect public health, were identified in measured samples. These were mainly emitted from outdoor sources (e.g., vehicular traffic) or indoor sources (e.g., household activities such as cooking and cleaning) or both. We concluded that region was the most important socioeconomic factor affecting children's VOC exposure, and the significant compounds were n-hexane (p = 0.006), 1,1,1-trichloroethane (p = 0.001), benzene (p = 0.003), toluene (p = 0.002), ethylbenzene (p = 0.020), m-, p-xylene (p = 0.014), dodecane (p = 0.003), and hexadecane (p = 0.001). Parental education, year of home construction and type of housing were also slightly correlated with personal VOC exposure. Only the concentration of o-xylene (p = 0.027) was significantly affected by the parental education, and the concentrations of benzene (p = 0.030) and 2-butanone (p = 0.049) by the type of housing. Also, tridecane (p = 0.049) and n-hexane (p = 0.033) were significantly associated with the year of home construction. When household activities such as cooking were performed indoors, children's VOC concentrations tended to be higher, especially for n-hexane, chloroform, heptane, toluene (p < 0.05), 1,1,1-trichloroethane, benzene, dodecane, and hexadecane (p < 0.01). However, smoking had a significant effect for only dodecane, and cleaning had no impact on any VOC concentrations. Considering both socioeconomic and personal behavioral factors simultaneously, socioeconomic

  15. 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. PMID:25892516

  16. LOW-VOC COATINGS FOR AUTOMOBILE REFINISHING USING NOVEL POLYMER RESINS

    EPA Science Inventory

    Coating operations release a significant portion of the non-mobile source, volatile organic compounds (VOCs) into the air. The U.S. EPA's Emissions Characterization and Prevention Branch has formulated novel low-VOC coatings for the automotive refinishing sector that reduce VOC l...

  17. U.S.-MEXICO BORDER PROGRAM ARIZONA BORDER STUDY--VOCS IN AIR ANALYTICAL RESULTS

    EPA Science Inventory

    The VOCs in Air data set contains analytical results for measurements of up to 45 volatile organic compounds (VOCs) in 183 air samples over 86 households. Results include samples taken using active and passive techniques. The primary VOCs of interest include benzene (CAS# 71-43...

  18. VOC breath biomarkers in lung cancer.

    PubMed

    Saalberg, Yannick; Wolff, Marcus

    2016-08-01

    This review provides an overview of volatile organic compounds (VOCs) which are considered lung cancer biomarkers for diagnostic breath analysis. It includes results of scientific publications from 1985 to 2015. The identified VOCs are listed and ranked according to their occurrence of nomination. The applied detection and sampling methods are specified but not evaluated. Possible reasons for the different results of the studies are stated. Among the most frequently emerging biomarkers are 2-butanone and 1-propanol as well as isoprene, ethylbenzene, styrene and hexanal. The outcome of this review may be helpful for the development of a lung cancer screening device. PMID:27221203

  19. Elimination of volatile organic compounds by biofiltration: a review.

    PubMed

    Nikiema, Josiane; Dastous, Paul-André; Heitz, Michèle

    2007-01-01

    Volatile organic compounds (VOCs) are pollutants that are responsible for the formation of the tropospheric ozone, one of the precursors of smog. VOCs are emitted by various industries including chemical plants, pulp and paper mills, pharmaceuticals, cosmetics, electronics and agri-food industries. Some VOCs cause odor pollution while many of them are harmful to environment and human or animal health. For the removal of VOCs, biofiltration, a biological process, has proved to be reliable when properly operated. This process has therefore been widely applied in Europe and North America. The main advantages associated with the use of biofiltration are related to its set-up, maintenance, and operating costs which are usually lower than those related to other VOCs control technologies and because it is less harmful for the environment than conventional processes like incineration. In the present paper, the main parameters (type, moisture, pH, and temperature of filter bed, microbial population, nutrients concentrations, and VOCs' inlet load) to be controlled during the biofiltration are identified and described in detail. The main phenomena involved in biofiltration are also discussed. For improving the efficiency of VOC control biotechnology, new techniques are now proposed that include the use of membranes, biphasic reactors, UV photolysis, and many others. PMID:18351227

  20. 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

  1. A Real-Time Fast-Flow Tube Study of VOC and Particulate Emissions from Electronic, Potentially Reduced-Harm, Conventional, and Reference Cigarettes

    PubMed Central

    Blair, Sandra L.; Epstein, Scott A.; Nizkorodov, Sergey A.; Staimer, Norbert

    2015-01-01

    Tobacco-free electronic cigarettes (e-cigarettes), which are currently not regulated by the FDA, have become widespread as a “safe” form of smoking. One approach to evaluate the potential toxicity of e-cigarettes and other types of potentially “reduced-harm” cigarettes is to compare their emissions of volatile organic compounds (VOCs), including reactive organic electrophillic compounds such as acrolein, and particulate matter to those of conventional and reference cigarettes. Our newly designed fast-flow tube system enabled us to analyze VOC composition and particle number concentration in real-time by promptly diluting puffs of mainstream smoke obtained from different brands of combustion cigarettes and e-cigarettes. A proton transfer reaction time-of-flight mass spectrometer (PTRMS) was used to analyze real-time cigarette VOC emissions with a 1 s time resolution. Particles were detected with a condensation particle counter (CPC). This technique offers real-time analysis of VOCs and particles in each puff without sample aging and does not require any sample pretreatment or extra handling. Several important determining factors in VOC and particle concentration were investigated: (1) puff frequency; (2) puff number; (3) tar content; (4) filter type. Results indicate that electronic cigarettes are not free from acrolein and acetaldehyde emissions and produce comparable particle number concentrations to those of combustion cigarettes, more specifically to the 1R5F reference cigarette. Unlike conventional cigarettes, which emit different amounts of particles and VOCs each puff, there was no significant puff dependence in the e-cigarette emissions. Charcoal filter cigarettes did not fully prevent the emission of acrolein and other VOCs. PMID:26726281

  2. Next Generation Air Monitoring (NGAM) VOC Sensor Evaluation Report

    EPA Science Inventory

    This report summarizes the results of next generation air monitor (NGAM) volatile organic compound (VOC) evaluations performed using both laboratory as well as field scale settings. These evaluations focused on challenging lower cost (<$2500) NGAM technologies to either controlle...

  3. ASSESSMENT OF VOC EMISSIONS FROM FIBERGLASS BOAT MANUFACTURING

    EPA Science Inventory

    The report presents an assessment of volatile organic compound (VOC) emissions from fiberglass boat manufacturing. escription of the industry structure is presented, including estimates of the number of facilities, their size, and geographic distribution. he fiberglass boat manuf...

  4. ASSESSMENT OF VOC EMISSIONS FROM FIBERGLASS BOAT MANUFACTURING

    EPA Science Inventory

    The report presents an assessment of volatile organic compound (VOC) emissions from fiberglass boat manufacturing. Description of the industry structure is presented, including estimates of the number of facilities, their size, and geographic distribution. The fiberglass boat m...

  5. 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. PMID:26819529

  6. 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

  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. Volatile Organic Compounds Enhance Allergic Airway Inflammation in an Experimental Mouse Model

    PubMed Central

    Bönisch, Ulrike; Böhme, Alexander; Kohajda, Tibor; Mögel, Iljana; Schütze, Nicole; von Bergen, Martin; Simon, Jan C.; Lehmann, Irina; Polte, Tobias

    2012-01-01

    Background Epidemiological studies suggest an association between exposure to volatile organic compounds (VOCs) and adverse allergic and respiratory symptoms. However, whether VOCs exhibit a causal role as adjuvants in asthma development remains unclear. Methods To investigate the effect of VOC exposure on the development of allergic airway inflammation Balb/c mice were exposed to VOCs emitted by new polyvinylchloride (PVC) flooring, sensitized with ovalbumin (OVA) and characterized in acute and chronic murine asthma models. Furthermore, prevalent evaporated VOCs were analyzed and mice were exposed to selected single VOCs. Results Exposure of mice to PVC flooring increased eosinophilic lung inflammation and OVA-specific IgE serum levels compared to un-exposed control mice. The increased inflammation was associated with elevated levels of Th2-cytokines. Long-term exposure to PVC flooring exacerbated chronic airway inflammation. VOCs with the highest concentrations emitted by new PVC flooring were N-methyl-2-pyrrolidone (NMP) and 2,2,4-trimethyl-1,3-pentanediol diisobutyrate (TXIB). Exposure to NMP or TXIB also increased the allergic immune response in OVA-sensitized mice. In vitro or in vivo exposure to NMP or TXIB reduced IL-12 production in maturing dendritic cells (DCs) and enhanced airway inflammation after adoptive DC transfer into Balb/c mice. At higher concentrations both VOCs induced oxidative stress demonstrated by increased isoprostane and glutathione-S-transferase-pi1 protein levels in the lung of non-sensitized mice. Treatment of PVC flooring-exposed mice with N-acetylcysteine prevented the VOC-induced increase of airway inflammation. Conclusions Our results demonstrate that exposure to VOCs may increase the allergic immune response by interfering with DC function and by inducing oxidative stress and has therefore to be considerate as risk factor for the development of allergic diseases. PMID:22802943

  9. Concentrations and co-occurrence correlations of 88 volatile organic compounds (VOCs) in the ambient air of 13 semi-rural to urban locations in the United States

    USGS Publications Warehouse

    Pankow, J.F.; Luo, W.; Bender, D.A.; Isabelle, L.M.; Hollingsworth, J.S.; Chen, C.; Asher, W.E.; Zogorski, J.S.

    2003-01-01

    The ambient air concentrations of 88 volatile organic compounds were determined in samples taken at 13 semi-rural to urban locations in Maine, Massachusetts, New Jersey, Pennsylvania, Ohio, Illinois, Louisiana, and California. The sampling periods ranged from 7 to 29 months, yielding a large data set with a total of 23,191 individual air concentration values, some of which were designated "ND" (not detected). For each compound at each sampling site, the air concentrations (ca, ppbV) are reported in terms of means, medians, and means of the detected values. The analytical method utilized adsorption/thermal desorption with air-sampling cartridges. The analytes included numerous halogenated alkanes, halogenated alkenes, ethers, alcohols, nitriles, esters, ketones, aromatics, a disulfide, and a furan. At some sites, the air concentrations of the gasoline-related aromatic compounds and the gasoline additive methyl tert-butyl ether were seasonally dependent, with concentrations that maximized in the winter. For each site studied here, the concentrations of some compounds were highly correlated one with another (e.g., the BTEX group (benzene, toluene, ethylbenzene, and the xylenes). Other aromatic compounds were also all generally correlated with one another, while the concentrations of other compound pairs were not correlated (e.g., benzene was not correlated with CFC-12). The concentrations found for the BTEX group were generally lower than the values that have been previously reported for urbanized and industrialized areas of other nations. ?? 2003 Elsevier Ltd. All rights reserved.

  10. Effects of heat and drought stress on post-illumination bursts of volatile organic compounds in isoprene-emitting and non-emitting poplar.

    PubMed

    Jud, Werner; Vanzo, Elisa; Li, Ziru; Ghirardo, Andrea; Zimmer, Ina; Sharkey, Thomas D; Hansel, Armin; Schnitzler, Jörg-Peter

    2016-06-01

    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

  11. 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

  12. Reactivity-adjusted VOC measurements by airtrack: A feasibility study

    SciTech Connect

    Chang, T.Y.; Hurley, M.D.; Nance, B.; Japar, S.M.

    1996-12-31

    Measurements of concentrations of ozone precursors, volatile organic compounds (VOC) and NO{sub x} (NO + NO{sub 2}), are essential to better understand ozone-precursor relationships in urban and regional areas. In the last two decades, major advances on measuring VOC and NO{sub x} have been made. Reliable techniques for measuring NO{sub x} are available currently, although it is difficult to measure NO{sub 2} without interferences of other species at routine monitoring sites. For VOC, reliable techniques are available for lighter nonmethane hydrocarbons (NMHC), and current techniques for measuring heavier NMHC and partially oxidized NMHC including carbonyl compounds are somewhat uncertain and are under further development. Currently available measurement techniques for VOC are time-consuming and expensive. Consequently, a simple measurement technique for reactivity-adjusted, total VOC would be valuable for evaluating ozone-precursor relationships. Recently, an integrated air quality assessment instrument, AIRTRAK, has been introduced. The uniqueness of the AIRTRAK is the possible, continuous measurements of ambient VOC. Measurements of smog formation coefficients and derivation of VOC concentrations are based on the integrated empirical rate (IER) model. However, the IER model does not appear to hold rigorously. Consequently, the capability of VOC measurements by AIRTRAK has not been demonstrated adequately. The purpose of the present paper is to investigate the VOC measurement capability of AIRTRAK after substantial experiences in flow-mode experiments using AIRTRAK at our laboratory. First, model simulations are performed to derive relationships between measured smog concentrations (by AIRTRAK) and ambient VOC concentrations. Using these relationships, numerical simulations are performed to simulate ambient VOC measurements. Further, preliminary investigations of implementing the present methodology to AIRTRAK are performed.

  13. Semivolatile organic compound emissions from heavy-duty trucks operating on diesel and bio-diesel fuel blends

    EPA Science Inventory

    This study measured semivolatile organic compounds (SVOCs) in particle matter (PM) emitted from three heavy-duty trucks equipped with modern after-treatment technologies. Emissions testing was conducted as described by the George et al. VOC study also presented as part of this se...

  14. MEMBRANE-MODERATED STRIPPING PROCESS FOR REMOVING VOCS FROM WATER IN A COMPOSITE HOLLOW FIBER MODULE. (R825511C027)

    EPA Science Inventory

    The "stripmeation" process for removing volatile organic compounds (VOCs) from water has been introduced and studied. An aqueous solution of the VOC is passed through the bores of hydrophobic microporous polypropylene hollow fibers having a plasma polymerized silicone ...

  15. VOC emissions from Norway spruce ( Picea abies L. [Karst]) twigs in the field—Results of a dynamic enclosure study

    NASA Astrophysics Data System (ADS)

    Grabmer, W.; Kreuzwieser, J.; Wisthaler, A.; Cojocariu, C.; Graus, M.; Rennenberg, H.; Steigner, D.; Steinbrecher, R.; Hansel, A.

    During the 2002 summer intensive field campaign of BEWA2000 a proton-transfer-reaction mass spectrometer (PTR-MS) was used for online determination of volatile organic compounds (VOC) emitted by Norway spruce ( Picea abies L. [Karst]) twigs in a dynamic sampling enclosure. Emissions of isoprenoids (isoprene and monoterpenes) and oxygenated VOC (OVOC; acetaldehyde, acetone, methanol, and ethanol) were investigated. Emissions showed clear diurnal patterns with high daytime emission rates amounting to 1.8 μg C g -1 dwt h -1 for the sum of monoterpenes and in the range of 0.1 to 0.6 μg C g -1 dwt h -1 for isoprene>acetone>ethanol>methanol. Data were used to validate existing models on isoprene and monoterpene emissions and to discuss environmental and physiological factors affecting VOC emissions. Isoprene and acetaldehyde emission rates were best modelled applying the Guenther 1993 temperature and solar radiation algorithm. Emissions of monoterpenes, acetone and ethanol were best described by a temperature-only exponential algorithm. Using these model approaches a maximum emission variability of 66% was covered (isoprene). Poor r2 values ranging from 0.15 to 0.42 were typical for oxygenated VOC emission modelling indicating the need for model improvement e.g. development of process-based models describing the emission as a result of biochemical de novo synthesis as well as physico-chemical transport properties inside the leaves.

  16. Red:far-red light conditions affect the emission of volatile organic compounds from barley (Hordeum vulgare), leading to altered biomass allocation in neighbouring plants

    PubMed Central

    Kegge, Wouter; Ninkovic, Velemir; Glinwood, Robert; Welschen, Rob A. M.; Voesenek, Laurentius A. C. J.; Pierik, Ronald

    2015-01-01

    Background and Aims Volatile organic compounds (VOCs) play various roles in plant–plant interactions, and constitutively produced VOCs might act as a cue to sense neighbouring plants. Previous studies have shown that VOCs emitted from the barley (Hordeum vulgare) cultivar ‘Alva’ cause changes in biomass allocation in plants of the cultivar ‘Kara’. Other studies have shown that shading and the low red:far-red (R:FR) conditions that prevail at high plant densities can reduce the quantity and alter the composition of the VOCs emitted by Arabidopsis thaliana, but whether this affects plant–plant signalling remains unknown. This study therefore examines the effects of far-red light enrichment on VOC emissions and plant–plant signalling between ‘Alva’ and ‘Kara’. Methods The proximity of neighbouring plants was mimicked by supplemental far-red light treatment of VOC emitter plants of barley grown in growth chambers. Volatiles emitted by ‘Alva’ under control and far-red light-enriched conditions were analysed using gas chromatography–mass spectrometry (GC-MS). ‘Kara’ plants were exposed to the VOC blend emitted by the ‘Alva’ plants that were subjected to either of the light treatments. Dry matter partitioning, leaf area, stem and total root length were determined for ‘Kara’ plants exposed to ‘Alva’ VOCs, and also for ‘Alva’ plants exposed to either control or far-red-enriched light treatments. Key Results Total VOC emissions by ‘Alva’ were reduced under low R:FR conditions compared with control light conditions, although individual volatile compounds were found to be either suppressed, induced or not affected by R:FR. The altered composition of the VOC blend emitted by ‘Alva’ plants exposed to low R:FR was found to affect carbon allocation in receiver plants of ‘Kara’. Conclusions The results indicate that changes in R:FR light conditions influence the emissions of VOCs in barley, and that these altered emissions

  17. GLOBAL INVENTORY OF VOLATILE ORGANIC COMPOUND EMISSIONS FROM ANTHROPOGENIC SOURCES

    EPA Science Inventory

    The paper discusses the development of a global inventory of anthropogenic volatile organic compound (VOC) emissions. t includes VOC estimates for seven classes of VOCs: paraffins, olefins, aromatics (benzene, toluene, xylene), formaldehyde, other aldehydes, other aromatics, and ...

  18. Detection, Composition and Treatment of Volatile Organic Compounds from Waste Treatment Plants

    PubMed Central

    Font, Xavier; Artola, Adriana; Sánchez, Antoni

    2011-01-01

    Environmental policies at the European and global level support the diversion of wastes from landfills for their treatment in different facilities. Organic waste is mainly treated or valorized through composting, anaerobic digestion or a combination of both treatments. Thus, there are an increasing number of waste treatment plants using this type of biological treatment. During waste handling and biological decomposition steps a number of gaseous compounds are generated or removed from the organic matrix and emitted. Different families of Volatile Organic Compounds (VOC) can be found in these emissions. Many of these compounds are also sources of odor nuisance. In fact, odors are the main source of complaints and social impacts of any waste treatment plant. This work presents a summary of the main types of VOC emitted in organic waste treatment facilities and the methods used to detect and quantify these compounds, together with the treatment methods applied to gaseous emissions commonly used in composting and anaerobic digestion facilities. PMID:22163835

  19. ANALYSIS OF VOCS IN AMBIENT AIR USING MULTISORBENT PACKINGS FOR VOC ACCUMULATION AND SAMPLE DRYING

    EPA Science Inventory

    Solid multisorbent packings have been characterized for trapping and release efficiency of trace (10-20 ppbv in humidified zero air) volatile organic compounds (VOCs). he use of a two-stage trapping system reduces sample water content typically by more than 95.5% while maintainin...

  20. Carbonyl compounds emitted by a diesel engine fuelled with diesel and biodiesel-diesel blends: Sampling optimization and emissions profile

    NASA Astrophysics Data System (ADS)

    Guarieiro, Lílian Lefol Nani; Pereira, Pedro Afonso de Paula; Torres, Ednildo Andrade; da Rocha, Gisele Olimpio; de Andrade, Jailson B.

    Biodiesel is emerging as a renewable fuel, hence becoming a promising alternative to fossil fuels. Biodiesel can form blends with diesel in any ratio, and thus could replace partially, or even totally, diesel fuel in diesel engines what would bring a number of environmental, economical and social advantages. Although a number of studies are available on regulated substances, there is a gap of studies on unregulated substances, such as carbonyl compounds, emitted during the combustion of biodiesel, biodiesel-diesel and/or ethanol-biodiesel-diesel blends. CC is a class of hazardous pollutants known to be participating in photochemical smog formation. In this work a comparison was carried out between the two most widely used CC collection methods: C18 cartridges coated with an acid solution of 2,4-dinitrophenylhydrazine (2,4-DNPH) and impinger bottles filled in 2,4-DNPH solution. Sampling optimization was performed using a 2 2 factorial design tool. Samples were collected from the exhaust emissions of a diesel engine with biodiesel and operated by a steady-state dynamometer. In the central body of factorial design, the average of the sum of CC concentrations collected using impingers was 33.2 ppmV but it was only 6.5 ppmV for C18 cartridges. In addition, the relative standard deviation (RSD) was 4% for impingers and 37% for C18 cartridges. Clearly, the impinger system is able to collect CC more efficiently, with lower error than the C18 cartridge system. Furthermore, propionaldehyde was nearly not sampled by C18 system at all. For these reasons, the impinger system was chosen in our study. The optimized sampling conditions applied throughout this study were: two serially connected impingers each containing 10 mL of 2,4-DNPH solution at a flow rate of 0.2 L min -1 during 5 min. A profile study of the C1-C4 vapor-phase carbonyl compound emissions was obtained from exhaust of pure diesel (B0), pure biodiesel (B100) and biodiesel-diesel mixtures (B2, B5, B10, B20, B50, B

  1. Generation and detection of metal ions and volatile organic compounds (VOCs) emissions from the pretreatment processes for recycling spent lithium-ion batteries.

    PubMed

    Li, Jia; Wang, Guangxu; Xu, Zhenming

    2016-06-01

    The recycling of spent lithium-ion batteries brings benefits to both economic and environmental terms, but it can also lead to contaminants in a workshop environment. This study focused on metals, non-metals and volatile organic compounds generated by the discharging and dismantling pretreatment processes which are prerequisite for recycling spent lithium-ion batteries. After discharging in NaCl solution, metal contents in supernate and concentrated liquor were detected. Among results of condition #2, #3, #4 and #5, supernate and concentrated liquor contain high levels of Na, Al, Fe; middle levels of Co, Li, Cu, Ca, Zn; and low levels of Mn, Sn, Cr, Zn, Ba, K, Mg, V. The Hg, Ag, Cr and V are not detected in any of the analyzed supernate. 10wt% NaCl solution was a better discharging condition for high discharge efficiency, less possible harm to environment. To collect the gas released from dismantled LIB belts, a set of gas collecting system devices was designed independently. Two predominant organic vapour compounds were dimethyl carbonate (4.298mgh(-1)) and tert-amylbenzene (0.749mgh(-1)) from one dismantled battery cell. To make sure the concentrations of dimethyl carbonate under recommended industrial exposure limit (REL) of 100mgL(-1), for a workshop on dismantling capacity of 1000kg spent LIBs, the minimum flow rate of ventilating pump should be 235.16m(3)h(-1). PMID:27021697

  2. Characterization of total ecosystem-scale biogenic VOC exchange at a Mediterranean oak-hornbeam forest

    NASA Astrophysics Data System (ADS)

    Schallhart, Simon; Rantala, Pekka; Nemitz, Eiko; Taipale, Ditte; Tillmann, Ralf; Mentel, Thomas F.; Loubet, Benjamin; Gerosa, Giacomo; Finco, Angelo; Rinne, Janne; Ruuskanen, Taina M.

    2016-06-01

    Recently, the number and amount of biogenically emitted volatile organic compounds (VOCs) has been discussed in great detail. Depending on the ecosystem, the published number varies between a dozen and several hundred compounds. We present ecosystem exchange fluxes from a mixed oak-hornbeam forest in the Po Valley, Italy. The fluxes were measured by a proton transfer reaction-time-of-flight (PTR-ToF) mass spectrometer and calculated using the eddy covariance (EC) method. Detectable fluxes were observed for up to 29 compounds, dominated by isoprene, which comprised over 60 % of the total upward flux (on a molar basis). The daily average of the total VOC upward flux was 10.4 nmol m-2 s-1. Methanol had the highest concentration and accounted for the largest downward flux. Methanol seemed to be deposited to dew, as the downward flux happened in the early morning, right after the calculated surface temperature came closest to the calculated dew point temperature.We estimated that up to 30 % of the upward flux of methyl vinyl ketone (MVK) and methacrolein (MACR) originated from atmospheric oxidation of isoprene. A comparison between two methods for the flux detection (manual and automated) was made. Their respective advantages and disadvantages were discussed and the differences in their results shown. Both provide comparable results.

  3. Energy Efficient Removal of Volatile Organic Compounds (VOCs) and Organic Hazardous Air Pollutants (o-HAPs) from Industrial Waste Streams by Direct Electron Oxidation

    SciTech Connect

    Testoni, A. L.

    2011-10-19

    This research program investigated and quantified the capability of direct electron beam destruction of volatile organic compounds and organic hazardous air pollutants in model industrial waste streams and calculated the energy savings that would be realized by the widespread adoption of the technology over traditional pollution control methods. Specifically, this research determined the quantity of electron beam dose required to remove 19 of the most important non-halogenated air pollutants from waste streams and constructed a technical and economic model for the implementation of the technology in key industries including petroleum refining, organic & solvent chemical production, food & beverage production, and forest & paper products manufacturing. Energy savings of 75 - 90% and green house gas reductions of 66 - 95% were calculated for the target market segments.

  4. Fungal succession in relation to volatile organic compounds emissions from Scots pine and Norway spruce leaf litter-decomposing fungi

    NASA Astrophysics Data System (ADS)

    Isidorov, Valery; Tyszkiewicz, Zofia; Pirożnikow, Ewa

    2016-04-01

    Leaf litter fungi are partly responsible for decomposition of dead material, nutrient mobilization and gas fluxes in forest ecosystems. It can be assumed that microbial destruction of dead plant materials is an important source of volatile organic compounds (VOCs) emitted into the atmosphere from terrestrial ecosystems. However, little information is available on both the composition of fungal VOCs and their producers whose community can be changed at different stages of litter decomposition. The fungal community succession was investigated in a litter bag experiment with Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) needle litter. The succession process can be divided into a several stages controlled mostly by changes in litter quality. At the very first stages of decomposition the needle litter was colonized by ascomycetes which can use readily available carbohydrates. At the later stages, the predominance of Trichoderma sp., the known producers of cellulolytic enzymes, was documented. To investigate the fungi-derived VOCs, eight fungi species were isolated. As a result of gas chromatographic analyses, as many as 75C2sbnd C15 fungal volatile compounds were identified. Most components detected in emissions were very reactive substances: the principal groups of VOCs were formed by monoterpenes, carbonyl compounds and aliphatic alcohols. It was found that production of VOCs by fungi is species specific: only 10 metabolites were emitted into the gas phase by all eight species. The reported data confirm that the leave litter decomposition is important source of reactive organic compounds under the forest canopy.

  5. Alternative control technology document: Control of VOC emissions from the application of agricultural pesticides

    SciTech Connect

    Not Available

    1993-03-01

    In many States, some of the ozone nonattainment areas are comprised primarily of agricultural counties where a potentially significant contribution to the ozone may result from area sources of volatile organic compounds (VOC's) emissions. A potential source of VOC emissions in agricultural counties is the release of organic compounds from the application of agricultural pesticides. The report provides technical information that State and local agencies can consider while developing strategies for reducing VOC emissions.

  6. VOCs in fixed film processes. I: Pilot studies

    SciTech Connect

    Parker, W.J.; Monteith, H.D.; Melcer, H.

    1996-07-01

    Stripping of volatile organic contaminants (VOCs) during wastewater treatment is of concern due to the potential of these compounds to contribute to stratospheric ozone depletion, ground-level smog formation, chronic toxicity to exposed workers, and odors. A study of the fate of volatile organic contaminants (VOCs) in trickling filters (TF) and rotating biological contactors (RBC) was performed. Of the target compounds investigated, tetrachloroethylene was volatilized to the greatest extent, while 1,1,2,2-tetrachloroethane was the least volatilized in the TF and bromoform was least volatilized in the RBC. Toulene, o-xylene and 1,3,5-trimethylbenzene were biodegraded to the greatest extent and 1,1,2,2-tetrachloroethane was least biodegraded. Increasing the hydraulic loading tended to increase the proportion of influent VOCs found in the TF effluent. Imposing effluent recycle on the TF increased the fraction of influent VOCs found in the effluent, but also decreased the fraction stripped and increased the fraction that was biodegraded. Increasing hydraulic loading to the RBC tended to increase the proportion of influent VOCs found in the effluent and off-gas. Increasing the RBC disc rotational speed increased the fraction that was biodegraded and decreased the fraction of VOCs found in the effluent and off-gas streams. The TF tended to have greater losses to volatilization than the RBC while the RBC maintained a greater fraction of the candidate VOCs in the process effluent than the TF. Differences between the processes with respect to biodegradation could not be inferred.

  7. Native Fluorescence Detection Methods and Detectors for Naphthalene and/or Other Volatile Organic Compound Vapors

    NASA Technical Reports Server (NTRS)

    Hug, William F. (Inventor); Bhartia, Rohit (Inventor); Reid, Ray D. (Inventor); Lane, Arthur L. (Inventor)

    2014-01-01

    Naphthalene, benzene, toluene, xylene, and other volatile organic compounds have been identified as serious health hazards. This is especially true for personnel working with JP8 jet fuel and other fuels containing naphthalene as well as other hazardous volatile organic compounds (VOCs). 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 naphthalene or other 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. The badges employ a new native fluorescence based detection method to identify and differentiate VOCs. The particular focus of some embodiments are the detection and identification of naphthalene while other embodiments are directed to detection and identification of other VOCs like aromatic hydrocarbons such as benzene, toluene, and xylene.

  8. Effect of mechanical damage on emission of volatile organic compounds from plant leaves and implications for evaluation of host plant specificity of prospective biological control agents of weeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Assessment of host plant specificity is a critical step in the evaluation of classical biological control agents of weeds, which is necessary for avoiding possible damage to nontarget plants. Volatile organic compounds (VOC) emitted by plants likely play an important role in determining which plant...

  9. The atmospheric chemistry of trace gases and particulate matter emitted by different land uses in Borneo

    PubMed Central

    MacKenzie, A. R.; Langford, B.; Pugh, T. A. M.; Robinson, N.; Misztal, P. K.; Heard, D. E.; Lee, J. D.; Lewis, A. C.; Jones, C. E.; Hopkins, J. R.; Phillips, G.; Monks, P. S.; Karunaharan, A.; Hornsby, K. E.; Nicolas-Perea, V.; Coe, H.; Gabey, A. M.; Gallagher, M. W.; Whalley, L. K.; Edwards, P. M.; Evans, M. J.; Stone, D.; Ingham, T.; Commane, R.; Furneaux, K. L.; McQuaid, J. B.; Nemitz, E.; Seng, Yap Kok; Fowler, D.; Pyle, J. A.; Hewitt, C. N.

    2011-01-01

    We report measurements of atmospheric composition over a tropical rainforest and over a nearby oil palm plantation in Sabah, Borneo. The primary vegetation in each of the two landscapes emits very different amounts and kinds of volatile organic compounds (VOCs), resulting in distinctive VOC fingerprints in the atmospheric boundary layer for both landscapes. VOCs over the Borneo rainforest are dominated by isoprene and its oxidation products, with a significant additional contribution from monoterpenes. Rather than consuming the main atmospheric oxidant, OH, these high concentrations of VOCs appear to maintain OH, as has been observed previously over Amazonia. The boundary-layer characteristics and mixing ratios of VOCs observed over the Borneo rainforest are different to those measured previously over Amazonia. Compared with the Bornean rainforest, air over the oil palm plantation contains much more isoprene, monoterpenes are relatively less important, and the flower scent, estragole, is prominent. Concentrations of nitrogen oxides are greater above the agro-industrial oil palm landscape than over the rainforest, and this leads to changes in some secondary pollutant mixing ratios (but not, currently, differences in ozone). Secondary organic aerosol over both landscapes shows a significant contribution from isoprene. Primary biological aerosol dominates the super-micrometre aerosol over the rainforest and is likely to be sensitive to land-use change, since the fungal source of the bioaerosol is closely linked to above-ground biodiversity. PMID:22006961

  10. The atmospheric chemistry of trace gases and particulate matter emitted by different land uses in Borneo.

    PubMed

    MacKenzie, A R; Langford, B; Pugh, T A M; Robinson, N; Misztal, P K; Heard, D E; Lee, J D; Lewis, A C; Jones, C E; Hopkins, J R; Phillips, G; Monks, P S; Karunaharan, A; Hornsby, K E; Nicolas-Perea, V; Coe, H; Gabey, A M; Gallagher, M W; Whalley, L K; Edwards, P M; Evans, M J; Stone, D; Ingham, T; Commane, R; Furneaux, K L; McQuaid, J B; Nemitz, E; Seng, Yap Kok; Fowler, D; Pyle, J A; Hewitt, C N

    2011-11-27

    We report measurements of atmospheric composition over a tropical rainforest and over a nearby oil palm plantation in Sabah, Borneo. The primary vegetation in each of the two landscapes emits very different amounts and kinds of volatile organic compounds (VOCs), resulting in distinctive VOC fingerprints in the atmospheric boundary layer for both landscapes. VOCs over the Borneo rainforest are dominated by isoprene and its oxidation products, with a significant additional contribution from monoterpenes. Rather than consuming the main atmospheric oxidant, OH, these high concentrations of VOCs appear to maintain OH, as has been observed previously over Amazonia. The boundary-layer characteristics and mixing ratios of VOCs observed over the Borneo rainforest are different to those measured previously over Amazonia. Compared with the Bornean rainforest, air over the oil palm plantation contains much more isoprene, monoterpenes are relatively less important, and the flower scent, estragole, is prominent. Concentrations of nitrogen oxides are greater above the agro-industrial oil palm landscape than over the rainforest, and this leads to changes in some secondary pollutant mixing ratios (but not, currently, differences in ozone). Secondary organic aerosol over both landscapes shows a significant contribution from isoprene. Primary biological aerosol dominates the super-micrometre aerosol over the rainforest and is likely to be sensitive to land-use change, since the fungal source of the bioaerosol is closely linked to above-ground biodiversity. PMID:22006961

  11. A simple method for screening emission sources of carbonyl compounds in indoor air.

    PubMed

    Yamashita, Shohei; Kume, Kazunari; Horiike, Toshiyuki; Honma, Nobuyuki; Fusaya, Masahiro; Ohura, Takeshi; Amagai, Takashi

    2010-06-15

    Volatile organic compounds (VOCs) emitted from building and furnishing materials are frequently observed in high concentrations in indoor air. Nondestructive analytical methods that determine the main parameters influencing concentration of the chemical substances are necessary to screen for sources of VOC emissions. Toward this goal, we have developed a new flux sampler, referred to herein as an emission cell for simultaneous multi-sampling (ECSMS), that is used for screening indoor emission sources of VOCs and for determining the emission rates of these sources. Because the ECSMS is based on passive sampling, it can be easily used on-site at a low cost. Among VOCs, low-molecular-weight carbonyl compounds including formaldehyde are frequently detected at high concentrations in indoor environments. In this study, we determined the reliability of the ECSMS for the collection of formaldehyde and other carbonyl compounds emitted from wood-based composites of medium density fiberboards and particleboards. We then used emission rates determined by the ECSMS to predict airborne concentrations of formaldehyde emitted from a bookshelf in a large chamber, and these data were compared to formaldehyde concentrations that were acquired simultaneously by means of an active sampling method. The values obtained from the two methods were quite similar, suggesting that ECSMS measurement is an effective method for screening primary sources influencing indoor concentrations of formaldehyde. PMID:20149530

  12. Study of the VOC emissions from a municipal solid waste storage pilot-scale cell: Comparison with biogases from municipal waste landfill site

    SciTech Connect

    Chiriac, R.; De Araujos Morais, J.; Carre, J.; Bayard, R.; Chovelon, J.M.; Gourdon, R.

    2011-11-15

    Highlights: > Follow-up of the emission of VOCs in a municipal waste pilot-scale cell during the acidogenesis and acetogenesis phases. > Study from the very start of waste storage leading to a better understanding of the decomposition/degradation of waste. > Comparison of the results obtained on the pilot-scale cell with those from 3 biogases coming from the same landfill site. > A methodology of characterization for the progression of the stabilization/maturation of waste is finally proposed. - Abstract: 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

  13. Exposure to fluoropolymers and VOCs during spray sealant product use.

    PubMed

    Rigler, Mark W; Longo, William E; Sauerhoff, Mitchell W

    2011-09-01

    Fluoropolymer based tile and fabric spray sealants were evaluated for the release of airborne fluoropolymer constituents and volatile organic compounds (VOCs) during typical product use scenarios in a simulated bathroom and a simulated recreational vehicle. Fluoride was quantified after oxygen bomb digestion of airborne spray collected from personal, area, and surface samples. VOCs were quantified by gas chromatography/mass spectrometry (GC/MS) and gas chromatography/flame ionization spectrometry (GC/FID). Tile grout sealant contained approximately 1% acrylic fluoropolymer resin and 90% VOCs not including propellants. VOCs were short- and medium- chain methylated isoparaffinic hydrocarbons. When horizontally spraying a bathroom shower floor, grout spray sealant released a non-detectable amount of fluoride (<0.8 µg/m3) and 400-1400 mg/m3 total VOCs. When vertically spraying a shower wall, up to 2.0 µg/m3 of fluoride and from 1000 to 2300 mg/m3 total VOCs were detected. Fabric spray sealant contained 1% acrylic fluoropolymer resin and approximately 90% VOCs including perchloroethylene (PERC). Fabric spray released from 0.5 to 2.3 µg/m3 fluoride inside a recreational vehicle in the absence of crosswinds and less than 0.5 µg/m3 fluoride in the presence of a 10 mph crosswind. VOC release measured 240-938 mg/m3 without crosswinds and 161-522 mg/m3 with crosswinds. These studies show that fluoropolymer constituents from fluorinated spray sealants were near non-detectable levels in the breathing zone in nearly all samples while VOCs were measured at elevated levels (>400 mg/m3). The toxicological consequences of elevated VOCs during sealant spraying and the effects of certain fluoropolymer constituents are discussed. PMID:21879949

  14. Identification and quantification of gaseous organic compounds emitted from biomass burning using two-dimensional gas chromatography/time-of-flight mass spectrometry

    NASA Astrophysics Data System (ADS)

    Hatch, L. E.; Luo, W.; Pankow, J. F.; Yokelson, R. J.; Stockwell, C. E.; Barsanti, K. C.

    2014-09-01

    The current understanding of secondary organic aerosol (SOA) formation within biomass burning (BB) plumes is limited by the incomplete identification and quantification of the non-methane organic compounds (NMOCs) emitted from such fires. Gaseous organic compounds were collected on sorbent cartridges during laboratory burns as part of the fourth Fire Lab at Missoula Experiment (FLAME-4), with analysis by two-dimensional gas chromatography/time-of-flight mass spectrometry (GC × GC / TOFMS). The sensitivity and resolving power of GC × GC / TOFMS allowed the acquisition of the most extensive data set of BB NMOCs to date, with measurements for 722 positively or tentatively identified compounds. Estimated emission factors (EFs) are presented for these compounds for burns of six different vegetative fuels, including conifer branches, grasses, agricultural residue, and peat. The number of compounds detected from individual burns ranged from 129 to 474, and included extensive isomer groups. For example, 38 monoterpene isomers were observed in the emissions from coniferous fuels; the isomeric ratios were found to be consistent with those reported in relevant essential oils, suggesting that the composition of such oils may be very useful when predicting fuel-dependent terpene emissions. Further, eleven sesquiterpenes were detected and tentatively identified, providing the first reported speciation of sesquiterpenes in gas-phase BB emissions. The calculated EFs for all measured compounds are compared and discussed in the context of potential SOA formation.

  15. Identification and quantification of gaseous organic compounds emitted from biomass burning using two-dimensional gas chromatography-time-of-flight mass spectrometry

    NASA Astrophysics Data System (ADS)

    Hatch, L. E.; Luo, W.; Pankow, J. F.; Yokelson, R. J.; Stockwell, C. E.; Barsanti, K. C.

    2015-02-01

    The current understanding of secondary organic aerosol (SOA) formation within biomass burning (BB) plumes is limited by the incomplete identification and quantification of the non-methane organic compounds (NMOCs) emitted from such fires. Gaseous organic compounds were collected on sorbent cartridges during laboratory burns as part of the fourth Fire Lab at Missoula Experiment (FLAME-4) and analyzed by two-dimensional gas chromatography-time-of-flight mass spectrometry (GC × GC-ToFMS). The sensitivity and resolving power of GC × GC-ToFMS allowed the acquisition of the most extensive data set of BB NMOCs to date, with measurements for 708 positively or tentatively identified compounds. Estimated emission factors (EFs) are presented for these compounds for burns of six different vegetative fuels, including conifer branches, grasses, agricultural residue, and peat. The number of compounds meeting the peak selection criteria ranged from 129 to 474 among individual burns, and included extensive isomer groups. For example, 38 monoterpene isomers were observed in the emissions from coniferous fuels; the isomeric ratios were found to be consistent with those reported in relevant essential oils, suggesting that the composition of such oils may be very useful when predicting fuel-dependent terpene emissions. Further, 11 sesquiterpenes were detected and tentatively identified, providing the first reported speciation of sesquiterpenes in gas-phase BB emissions. The calculated EFs for all measured compounds are compared and discussed in the context of potential SOA formation.

  16. A genetically-based latitudinal cline in the emission of herbivore-induced plant volatile organic compounds.

    PubMed

    Wason, Elizabeth L; Agrawal, Anurag A; Hunter, Mark D

    2013-08-01

    The existence of predictable latitudinal variation in plant defense against herbivores remains controversial. A prevailing view holds that higher levels of plant defense evolve at low latitudes compared to high latitudes as an adaptive plant response to higher herbivore pressure on low-latitude plants. To date, this prediction has not been examined with respect to volatile organic compounds (VOCs) that many plants emit, often thus attracting the natural enemies of herbivores. Here, we compared genetically-based constitutive and herbivore-induced aboveground vegetative VOC emissions from plants originating across a gradient of more than 10° of latitude (>1,500 km). We collected headspace VOCs from Asclepias syriaca (common milkweed) originating from 20 populations across its natural range and grown in a common garden near the range center. Feeding by specialist Danaus plexippus (monarch) larvae induced VOCs, and field environmental conditions (temperature, light, and humidity) also influenced emissions. Monarch damage increased plant VOC concentrations and altered VOC blends. We found that genetically-based induced VOC emissions varied with the latitude of plant population origin, although the pattern followed the reverse of that predicted-induced VOC concentration increased with increasing latitude. This pattern appeared to be driven by a greater induction of sesquiterpenoids at higher latitudes. In contrast, constitutive VOC emission did not vary systematically with latitude, and the induction of green leafy volatiles declined with latitude. Our results do not support the prevailing view that plant defense is greater at lower than at higher latitudes. That the pattern holds only for herbivore-induced VOC emission, and not constitutive emission, suggests that latitudinal variation in VOCs is not a simple adaptive response to climatic factors. PMID:23888386

  17. Estimation of VOC emissions from produced-water treatment ponds in Uintah Basin oil and gas field using modeling techniques

    NASA Astrophysics Data System (ADS)

    Tran, H.; Mansfield, M. L.; Lyman, S. N.; O'Neil, T.; Jones, C. P.

    2015-12-01

    Emissions from produced-water treatment ponds are poorly characterized sources in oil and gas emission inventories that play a critical role in studying elevated winter ozone events in the Uintah Basin, Utah, U.S. Information gaps include un-quantified amounts and compositions of gases emitted from these facilities. The emitted gases are often known as volatile organic compounds (VOCs) which, beside nitrogen oxides (NOX), are major precursors for ozone formation in the near-surface layer. Field measurement campaigns using the flux-chamber technique have been performed to measure VOC emissions from a limited number of produced water ponds in the Uintah Basin of eastern Utah. Although the flux chamber provides accurate measurements at the point of sampling, it covers just a limited area of the ponds and is prone to altering environmental conditions (e.g., temperature, pressure). This fact raises the need to validate flux chamber measurements. In this study, we apply an inverse-dispersion modeling technique with evacuated canister sampling to validate the flux-chamber measurements. This modeling technique applies an initial and arbitrary emission rate to estimate pollutant concentrations at pre-defined receptors, and adjusts the emission rate until the estimated pollutant concentrations approximates measured concentrations at the receptors. The derived emission rates are then compared with flux-chamber measurements and differences are analyzed. Additionally, we investigate the applicability of the WATER9 wastewater emission model for the estimation of VOC emissions from produced-water ponds in the Uintah Basin. WATER9 estimates the emission of each gas based on properties of the gas, its concentration in the waste water, and the characteristics of the influent and treatment units. Results of VOC emission estimations using inverse-dispersion and WATER9 modeling techniques will be reported.

  18. Infant exposure to emissions of volatile organic compounds from crib mattresses.

    PubMed

    Boor, Brandon E; Järnström, Helena; Novoselac, Atila; Xu, Ying

    2014-03-18

    Infants spend most of their time sleeping and are likely to be exposed to elevated concentrations of chemicals released from their crib mattresses. Small-scale chamber experiments were conducted to determine the area-specific emission rates (SERs) of volatile organic compounds (VOCs) in a collection of twenty new and used crib mattresses. All mattress samples were found to emit VOCs and the mean values of total VOC (TVOC) SERs were 56 μg/m(2)h at 23 °C and 139 μg/m(2)h at 36 °C. TVOC SERs were greater for new mattresses compared to used ones and were influenced by the type of foam material and the presence of mattress cover layer. A variety of VOCs were identified, with polyurethane foam releasing a greater diversity of VOCs compared to polyester foam. Large-scale chamber experiments were conducted with an infant thermal manikin. TVOC concentrations sampled in the breathing zone and interior pore air of the crib mattress foam were found to be greater than the bulk room air by factors in the range of 1.8 to 2.4 and 7.5 to 21, respectively. The results suggest that crib mattresses are an important source of VOCs and infant exposure to VOCs are possibly elevated in their sleep microenvironments. PMID:24548111

  19. Effects of liquid VOC concentration and salt content on partitioning equilibrium of hydrophilic VOC at air-sweat interface

    NASA Astrophysics Data System (ADS)

    Cheng, Wen-Hsi; Chu, Fu-Sui; Su, Tzy-I.

    Volatile organic compounds (VOCs) must initially be absorbed by sweat on the surface of skin for human VOC dermal exposure. The partitioning equilibrium at the air-sweat interface is given by p=Cg*/C, where pc is the partitioning coefficient, and Cg* is the gaseous concentration in equilibrium with the aqueous VOC concentration ( CL) at a constant water temperature ( Tw). A series of thermodynamic functions of Cg*(C,T) are presented, as well as the values of pc, and the heat of gaseous-liquid phase transfer (Δ Htr) for tested VOCs, including iso-propanol (IPA, CL=12-120 mg L -1) and methyl ethyl ketone (MEK, CL=10-80 mg L -1) to determine the effects of liquid VOC concentration and salt contents of sweat on pc of hydrophilic VOCs. Experimental data reveal that the pc values of IPA and MEK drop as the liquid VOC concentrations increasing from 10 to 120 mg L -1. However, sodium salt content in human sweat (sodium chloride and sodium lactate) induces the effect of salt, indicating the increase in pc. Notably, neither urea nor ammonia in human sweat increase pc. Artificial sweat, consisting of sodium chloride 0.47%, urea 0.05%, ammonia 0.004% and sodium lactate 0.6%, was used to evaluate the increase in the pc values of IPA and MEK. The liquid VOC concentration effect simultaneously develops together with the salt effect on the partition at the interface of air-sweat for hydrophilic VOC solutions. The pc values of IPA for artificial sweat decrease as much as 32.5% as CL increases from 12 to 120 mg L -1 at 300 K, and those of MEK drop by as much as 70.9% as CL increases from 10 to 80 mg L -1 at 300 K. This investigation provides a basis for elucidating the assessment of human dermal exposure to hydrophilic VOCs.

  20. Thermal response and recyclability of poly(stearylacrylate-co-ethylene glycol dimethacrylate) gel as a VOCs absorbent

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The development of absorbent materials for volatile organic compounds (VOCs) is in demand for a variety of environmental applications including protective barriers for VOCs point sources. One of the challenges for the currently available VOCs absorbents is their recyclability. In this study, we syn...

  1. EVALUATION OF SINK EFFECTS ON VOCS FROM A LATEX PAINT

    EPA Science Inventory

    The sink strength of two common indoor materials, a carpet and a gypsum board, was evaluated by environmental chamber tests with four volatile organic compounds (VOCs): propylene glycol, ethylene glycol, 2-(2-butoxyethoxy)ethanol (BEE), and texanol. These oxygenated compounds rep...

  2. Analyses of volatile organic compounds from human skin

    PubMed Central

    Gallagher, M.; Wysocki, C.J.; Leyden, J.J.; Spielman, A.I.; Sun, X.; Preti, G.

    2008-01-01

    Summary Background Human skin emits a variety of volatile metabolites, many of them odorous. Much previous work has focused upon chemical structure and biogenesis of metabolites produced in the axillae (underarms), which are a primary source of human body odour. Nonaxillary skin also harbours volatile metabolites, possibly with different biological origins than axillary odorants. Objectives To take inventory of the volatile organic compounds (VOCs) from the upper back and forearm skin, and assess their relative quantitative variation across 25 healthy subjects. Methods Two complementary sampling techniques were used to obtain comprehensive VOC profiles, viz., solid-phase micro extraction and solvent extraction. Analyses were performed using both gas chromatography/mass spectrometry and gas chromatography with flame photometric detection. Results Nearly 100 compounds were identified, some of which varied with age. The VOC profiles of the upper back and forearm within a subject were, for the most part, similar, although there were notable differences. Conclusions The natural variation in nonaxillary skin odorants described in this study provides a baseline of compounds we have identified from both endogenous and exogenous sources. Although complex, the profiles of volatile constituents suggest that the two body locations share a considerable number of compounds, but both quantitative and qualitative differences are present. In addition, quantitative changes due to ageing are also present. These data may provide future investigators of skin VOCs with a baseline against which any abnormalities can be viewed in searching for biomarkers of skin diseases. PMID:18637798

  3. [VOCs tax policy on China's economy development].

    PubMed

    Liu, Chang-Xin; Wang, Yu-Fei; Wang, Hai-Lin; Hao, Zheng-Ping; Wang, Zheng

    2011-12-01

    In this paper, environmental tax was designed to control volatile organic compounds (VOCs) emissions. Computable general equilibrium (CGE) model was used to explore the impacts of environmental tax (in forms of indirect tax) on the macro-economy development at both national and sector levels. Different levels of tax were simulated to find out the proper tax rate. It is found out that imposing environmental tax on high emission sectors can cause the emission decreased immediately and can lead to negative impacts on macro-economy indicators, such as GDP (gross domestic products), total investment, total product and the whole consumption etc. However, only the government income increased. In addition, the higher the tax rate is, the more pollutants can be reduced and the worse economic effects can be caused. Consequently, it is suggested that, the main controlling policies of VOCs abatement should be mandatory orders, and low environmental tax can be implemented as a supplementary. PMID:22468510

  4. Volatile Organic Compound Emissions from Natural Gas Facilities in the Denver-Julesburg Basin, the Uintah Basin and the Marcellus Shale

    NASA Astrophysics Data System (ADS)

    Li, X.; Omara, M.; Sullivan, M.; Subramanian, R.; Robinson, A. L.; Presto, A. A.

    2015-12-01

    Natural gas has been widely considered as a "bridge" fuel in the future. Because of the rapid advancement of horizontal drilling and hydraulic fracturing techniques, the production of crude oil and natural gas in US increased dramatically in recent years; and currently natural gas contributes to about 25% of total US energy consumption. Recent studies suggest that shale gas extraction facilities may emit Volatile Organic Compounds (VOCs), which could contribute to the formation of ozone and affect regional air quality, public health and climate change. In this study we visited 37 natural gas facilities in Denver-Julesburg and Uintah Basins from March to May, 2015. VOCs and methane concentrations were measured downwind of individual facilities with our mobile lab. In total 13 VOCs, including benzene and toluene, were measured by a SRI 8610C Gas Chromatograph. Similar measurements will be conducted in the Marcellus Shale in late August 2015. Preliminary results show that VOC emissions from individual shale gas facilities are variable, which suggests that a single VOC profile may not characterize all natural gas production facilities, though there may be some common characteristics. Measured VOC concentrations will be normalized to concurrently-measured methane emissions, and coupled with methane emission rates measured at these facilities, used to obtain VOC emission factors from natural gas production. This presentation will also compare VOC emission rates from the Marcellus shale with that from the Denver-Julesburg and Uintah basins.

  5. Optimization of headspace solid phase microextraction for the analysis of microbial volatile organic compounds emitted by fungi: Application to historical objects.

    PubMed

    Sawoszczuk, Tomasz; Syguła-Cholewińska, Justyna; del Hoyo-Meléndez, Julio M

    2015-08-28

    The main goal of this work was to optimize the SPME sampling method for measuring microbial volatile organic compounds (MVOCs) emitted by active molds that may deteriorate historical objects. A series of artificially aged model materials that resemble those found in historical objects was prepared and evaluated after exposure to four different types of fungi. The investigated pairs consisted of: Alternaria alternata on silk, Aspergillus niger on parchment, Chaetomium globosum on paper and wool, and Cladosporium herbarum on paper. First of all, a selection of the most efficient SPME fibers was carried out as there are six different types of fibers commercially available. It was important to find a fiber that absorbs the biggest number and the highest amount of MVOCs. The results allowed establishing and selecting the DVB/CAR/PDMS fiber as the most effective SPME fiber for this kind of an analysis. Another task was to optimize the time of MVOCs extraction on the fiber. It was recognized that a time between 12 and 24h is adequate for absorbing a high enough amount of MVOCs. In the last step the temperature of MVOCs desorption in the GC injection port was optimized. It was found that desorption at a temperature of 250°C allowed obtaining chromatograms with the highest abundances of compounds. To the best of our knowledge this work constitutes the first attempt of the SPME method optimization for sampling MVOCs emitted by molds growing on historical objects. PMID:26209190

  6. Temperature-dependent release of volatile organic compounds of eucalypts by direct analysis in real time (DART) mass spectrometry.

    PubMed

    Maleknia, Simin D; Vail, Teresa M; Cody, Robert B; Sparkman, David O; Bell, Tina L; Adams, Mark A

    2009-08-01

    A method is described for the rapid identification of biogenic, volatile organic compounds (VOCs) emitted by plants, including the analysis of the temperature dependence of those emissions. Direct analysis in real time (DART) enabled ionization of VOCs from stem and leaf of several eucalyptus species including E. cinerea, E. citriodora, E. nicholii and E. sideroxylon. Plant tissues were placed directly in the gap between the DART ionization source skimmer and the capillary inlet of the time-of-flight (TOF) mass spectrometer. Temperature-dependent emission of VOCs was achieved by adjusting the temperature of the helium gas into the DART ionization source at 50, 100, 200 and 300 degrees C, which enabled direct evaporation of compounds, up to the onset of pyrolysis of plant fibres (i.e. cellulose and lignin). Accurate mass measurements facilitated by TOF mass spectrometry provided elemental compositions for the VOCs. A wide range of compounds was detected from simple organic compounds (i.e. methanol and acetone) to a series of monoterpenes (i.e. pinene, camphene, cymene, eucalyptol) common to many plant species, as well as several less abundant sesquiterpenes and flavonoids (i.e. naringenin, spathulenol, eucalyptin) with antioxidant and antimicrobial properties. The leaf and stem tissues for all four eucalypt species showed similar compounds. The relative abundances of methanol and ethanol were greater in stem wood than in leaf tissue suggesting that DART could be used to investigate the tissue-specific transport and emissions of VOCs. PMID:19551840

  7. Modeling unsteady-state VOC transport in simulated waste drums. Revision 1

    SciTech Connect

    Liekhus, K.J.; Gresham, G.L.; Peterson, E.S.; Rae, C.; Hotz, N.J.; Connolly, M.J.

    1994-01-01

    This report is a revision of an EG&G Idaho informal report originally titled Modeling VOC Transport in Simulated Waste Drums. 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 permeability had been measured.

  8. Volatile organic compounds and metal leaching from composite products made from fiberglass-resin portion of printed circuit board waste.

    PubMed

    Guo, Jie; Jiang, Ying; Hu, Xiaofang; Xu, Zhenming

    2012-01-17

    This study focused on the volatile organic compounds (VOCs) and metal leaching from three kinds of composite products made from fiberglass-resin portion (FRP) of crushed printed circuit board (PCB) waste, including phenolic molding compound (PMC), wood plastic composite (WPC), and nonmetallic plate (NMP). Released VOCs from the composite products were quantified by air sampling on adsorbent followed by thermal desorption and GC-MS analysis. The results showed that VOCs emitted from composite products originated from the added organic components during manufacturing process. Phenol in PMC panels came primarily from phenolic resin, and the airborne concentration of phenol emitted from PMC product was 59.4 ± 6.1 μg/m(3), which was lower than odor threshold of 100% response for phenol (180 μg/m(3)). VOCs from WPC product mainly originated from wood flour, e.g., benzaldehyde, octanal, and d-limonene were emitted in relatively low concentrations. For VOCs emitted from NMP product, the airborne concentration of styrene was the highest (633 ± 67 μg/m(3)). Leaching characteristics of metal ions from composite products were tested using acetic acid buffer solution and sulphuric acid and nitric acid solution. Then the metal concentrations in the leachates were tested by ICP-AES. The results showed that only the concentration of Cu (average = 893 mg/L; limit = 100 mg/L) in the leachate solution of the FRP using acetic acid buffer solution exceeded the standard limit. However, concentrations of other metal ions (Pb, Cd, Cr, Ba, and Ni) were within the standard limit. All the results indicated that the FRP in composite products was not a major concern in terms of environmental assessment based upon VOCs tests and leaching characteristics. PMID:22142243

  9. Volatile organic compounds from fungi isolated after hurricane katrina induce developmental defects and apoptosis in a Drosophila melanogaster model.

    PubMed

    Inamdar, Arati A; Bennett, Joan W

    2015-05-01

    In previous work, our laboratory developed a Drosophila model for studying the adverse effects of fungal volatile organic compounds (VOCs) emitted by growing cultures of molds. In this report, we have extended these studies and compared the toxic effects of fungal VOCs emitted from living cultures of four molds isolated after Hurricane Katrina from a flooded home in New Orleans. Strains of Aspergillus, Mucor, Penicillium, and Trichoderma were grown with wild-type larvae and the toxic effects of volatile products on the developmental stages of Drosophila larvae were evaluated. Furthermore, heterozygous mutants of Drosophila carrying the apoptotic genes, reaper and dronc, were used to assess the role of apoptosis in fungal VOCs mediated toxicity. Third-instar larvae of Drosophila carrying these apoptotic genes were exposed to fungal VOCs emitted from growing mold cultures for 10 days. The larval strains carrying apoptopic genes survived longer than the control wild type larvae; moreover, of those that survived, heterozygous reaper and dronc strains progressed to pupae and adult phases more rapidly, suggesting that fungal VOCs may induce apoptotic changes in flies. These data lend support to the use of Drosophila as an inexpensive and genetically versatile toxicological model to investigate the mechanistic basis for some of the human illnesses/symptoms associated with exposure to mold-contaminated indoor air, especially after hurricanes. PMID:24307503

  10. Low VOC drying of lumber and wood panel products: Progress report No. 3

    SciTech Connect

    Boerner, J.; Su, Wei; Banerjee, Sujit; Shmulsky, Rubin; Thompson, Ashlie; Ingram, Leonard; Conners, Terry

    1997-03-01

    Studies on the removal of volatile organic compounds (VOC) from wood or wood products were conducted. Steam-induced extraction of VOC from oriented strand board (OSB) was studied using a tube furnace at 130 C which resulted in over 50% removal in 30 minutes. RF treatment of softwood lumber removed up to 68% of VOC in 20 minutes. Studies on the transport of moisture in wood confirmed that transport is greatest in the transverse surface, followed by the tangential and radial faces.

  11. COMPARISON OF PROCEDURES TO DETERMINE ADSORPTION CAPACITY OF VOLATILE ORGANIC COMPOUNDS ON ACTIVATED CARBON

    EPA Science Inventory

    Numerous volatile organic compounds (VOCs) are under regulatory consideration for inclusion in the National Primary Drinking Water Standards. Adsorption is a cost-effective treatment technology for control of VOCs. Adsorption capacities were determined for fifteen VOCs in distill...

  12. HENRY'S LAW CONSTANTS AND MICELLAR PARTITIONING OF VOLATILE ORGANIC COMPOUNDS IN SURFACTANT SOLUTIONS

    EPA Science Inventory

    Partitioning of volatile organic compounds (VOCs) into surfactant micelles affects the apparent vapor-liquid equilibrium of VOCs in surfactant solutions. This partitioning will complicate removal of VOCs from surfactant solutions by standard separation processes. Headspace expe...

  13. Effects of biological and methodological factors on volatile organic compound patterns during cultural growth of Mycobacterium avium ssp. paratuberculosis.

    PubMed

    Küntzel, Anne; Fischer, Sina; Bergmann, Andreas; Oertel, Peter; Steffens, Markus; Trefz, Phillip; Miekisch, Wolfram; Schubert, Jochen K; Reinhold, Petra; Köhler, Heike

    2016-01-01

    Mycobacterium avium ssp. paratuberculosis (MAP) causes chronic granulomatous enteritis in ruminants. Bacterial growth is still the diagnostic 'gold standard', but is very time consuming. MAP-specific volatile organic compounds (VOCs) above media could accelerate cultural diagnosis. The aim of this project was to assess the kinetics of a VOC profile linked to the growth of MAP in vitro. The following sources of variability were taken into account: five different culture media, three different MAP strains, inoculation with different bacterial counts, and different periods of incubation. Needle-trap microextraction was employed for pre-concentration of VOCs, and gas chromatography-mass spectrometry for subsequent analysis. All volatiles were identified and calibrated by analysing pure references at different concentration levels. More than 100 VOCs were measured in headspaces above MAP-inoculated and control slants. Results confirmed different VOC profiles above different culture media. Emissions could be assigned to either egg-containing media or synthetic ingredients. 43 VOCs were identified as potential biomarkers of MAP growth on Herrold's Egg Yolk Medium without significant differences between the tree MAP strains. Substances belonged to the classes of alcohols, aldehydes, esters, ketones, aliphatic and aromatic hydrocarbons. With increasing bacterial density the VOC concentrations above MAP expressed different patterns: the majority of substances increased (although a few decreased after reaching a peak), but nine VOCs clearly decreased. Data support the hypotheses that (i) bacteria emit different metabolites on different culture media; (ii) different MAP strains show uniform VOC patterns; and (iii) cultural diagnosis can be accelerated by taking specific VOC profiles into account. PMID:27604146

  14. Rendering plant emissions of volatile organic compounds during sterilization and cooking processes.

    PubMed

    Bhatti, Z A; Maqbool, F; Langenhove, H V

    2014-01-01

    The rendering process emits odorous volatile compounds in the atmosphere; if these volatile organic compounds (VOCs) are not handled properly they can cause a serious environmental problem. During this process not all emitted compounds are odorous and hazardous but some of them have been found associated with health problems. Samples were collected in the plastic bags from the Arnout rendering plant. In this study, VOCs emission from two different processes (cooking and sterilization) was compared. For the analysis of various emitted compounds, gas chromatograph and mass spectrophotometer were used. A sterilization process was added in the rendering plant to inactivate the prion protein from meat bone meal prepared during the rendering process. The identification of mass spectrum was performed by using a mass spectral database system. The most odorous classes of compounds identified were aliphatic hydrocarbons (HCs) (29.24%), furans (28.74%), aromatic HCs (18.32%), most important sulphur-containing compounds (12.15%), aldehyde (10.91%) and ketones (0.60%). Emissions released during cooking and sterilization were 32.73 x 10(2) and 36.85 x 10(2) mg m(-3), respectively. In this study, it was observed that after the addition of the sterilization process VOCs' emissions were increased. A total of 87 mg m(-3) dimethyl disulphide (DMS) was detected only during the cooking process, whereas dimethly trisulphide (DMTS) was detected in both cooking (300 mg m(-3)) and sterilization (301 mg m(-3)) processes. About 11 mg m3 of DMS was detected during the cooking process, which was a small concentration compared with 299 mg m(-3) found during the sterilization process. At high temperature and pressure, DMTS and DMS were released more than any other sulphur-containing compounds. A condenser was applied to control the combined emission and it was successful in the reduction of VOCs to 22.83 x 10(2) mg m(-3) (67% reduction). PMID:24701929

  15. The effects of operating conditions on semivolatile organic compounds emitted from light-duty, gasoline-powered motor vehicles

    EPA Science Inventory

    A thermal extraction-gas chromatography-mass spectrometry (TE-GC-MS) method was used to quantitatively examine organic compounds in fine particulate matter (PM2.5) collected from light-duty, gasoline-powered vehicle (LDGV) exhaust. Emissions were analyzed from a subset of 18 vehi...

  16. Use of mass spectrometric methods for field screening of VOC`s

    SciTech Connect

    Evans, J.C.

    1994-11-01

    While mass spectrometric (MS) methods of chemical analysis, particularly gas chromatography-mass spectrometry (GC/MS), have been the mainstay of environmental organic analytical techniques in the laboratory through the use of EPA and other standard methods, field implementation is relatively rare. Instrumentation and methods now exist for utilizing MS and GC/MS techniques in the field for analysis of VOC`s in gas phase, aqueous, and soil media. Examples of field investigations utilizing HP 5971A and Viking SpectraTrak systems for analysis of VOC`s in all three media will be presented. Mass spectral methods were found to offer significant advantages in terms of speed of analysis and reliability of compound identification over field gas chromatography (GC) methods while preserving adequate levels of detection sensitivity. The soil method in particular provides a method for rapid in-field analysis of methanol preserved samples thus minimizing the problem of volatiles loss which typically occurs with routine use of the EPA methods and remote analysis. The high cost of MS instrumentation remains a major obstacle to more widespread use.

  17. In Vivo Volatile Organic Compound Signatures of Mycobacterium avium subsp. paratuberculosis

    PubMed Central

    Bergmann, Andreas; Trefz, Phillip; Fischer, Sina; Klepik, Klaus; Walter, Gudrun; Steffens, Markus; Ziller, Mario; Schubert, Jochen K.; Reinhold, Petra; Köhler, Heike; Miekisch, Wolfram

    2015-01-01

    Mycobacterium avium ssp. paratuberculosis (MAP) is the causative agent of a chronic enteric disease of ruminants. Available diagnostic tests are complex and slow. In vitro, volatile organic compound (VOC) patterns emitted from MAP cultures mirrored bacterial growth and enabled distinction of different strains. This study was intended to determine VOCs in vivo in the controlled setting of an animal model. VOCs were pre-concentrated from breath and feces of 42 goats (16 controls and 26 MAP-inoculated animals) by means of needle trap microextraction (breath) and solid phase microextraction (feces) and analyzed by gas chromatography/ mass spectrometry. Analyses were performed 18, 29, 33, 41 and 48 weeks after inoculation. MAP-specific antibodies and MAP-specific interferon-γ-response were determined from blood. Identities of all marker-VOCs were confirmed through analysis of pure reference substances. Based on detection limits in the high pptV and linear ranges of two orders of magnitude more than 100 VOCs could be detected in breath and in headspace over feces. Twenty eight substances differed between inoculated and non-inoculated animals. Although patterns of most prominent substances such as furans, oxygenated substances and hydrocarbons changed in the course of infection, differences between inoculated and non-inoculated animals remained detectable at any time for 16 substances in feces and 3 VOCs in breath. Differences of VOC concentrations over feces reflected presence of MAP bacteria. Differences in VOC profiles from breath were linked to the host response in terms of interferon-γ-response. In a perspective in vivo analysis of VOCs may help to overcome limitations of established tests. PMID:25915653

  18. Analysis of volatile compounds emitted by filamentous fungi using solid-phase microextraction-gas chromatography/mass spectrometry.

    PubMed

    Roze, Ludmila V; Beaudry, Randolph M; Linz, John E

    2012-01-01

    Here, we describe a solid-phase microextraction-gas chromatography/mass spectrometry (SPME-GC/MS) analytical approach that identifies and analyzes volatile compounds in the headspace above a live fungal culture. This approach is a sensitive, solvent-free, robust technique; most importantly from a practical standpoint, this approach is noninvasive and requires minimal sample handling. Aliquots of liquid fungal cultures are placed into vials equipped with inert septa and equilibrated at a constant temperature, and headspace gases are sampled using an SPME fiber inserted through the septum into the headspace above the fungal culture for a standardized period of time. The outer polymer coating of a fused silica fiber absorbs volatiles from the headspace; the volatiles are then desorbed in the hot GC inlet and chromatographed in the usual manner. The separated compounds are subsequently identified by mass spectrometry. All steps in volatile profiling of a single sample from volatile sorption on a fiber to obtaining a list of volatiles can take as little as 15 min or can be extended to several hours if longer sorption is required for compounds present at very low levels and/or have low rates of diffusion. PMID:23065613

  19. Highly Efficient Near-Infrared Delayed Fluorescence Organic Light Emitting Diodes Using a Phenanthrene-Based Charge-Transfer Compound.

    PubMed

    Wang, Shipan; Yan, Xianju; Cheng, Zong; Zhang, Hongyu; Liu, Yu; Wang, Yue

    2015-10-26

    Significant efforts have been made to develop high-efficiency organic light-emitting diodes (OLEDs) employing thermally activated delayed fluorescence (TADF) emitters with blue, green, yellow, and orange-red colors. However, efficient TADF materials with colors ranging from red, to deep-red, to near-infrared (NIR) have been rarely reported owing to the difficulty in molecular design. Herein, we report the first NIR TADF molecule TPA-DCPP (TPA=triphenylamine; DCPP=2,3-dicyanopyrazino phenanthrene) which has a small singlet-triplet splitting (ΔEST ) of 0.13 eV. Its nondoped OLED device exhibits a maximum external quantum efficiency (EQE) of 2.1 % with a Commission International de L'Éclairage (CIE) coordinate of (0.70, 0.29). Moreover, an extremely high EQE of nearly 10 % with an emission band at λ=668 nm has been achieved in the doped device, which is comparable to the most-efficient deep-red/NIR phosphorescent OLEDs with similar electroluminescent spectra. PMID:26480338

  20. Development of a multi-VOC reference material for quality assurance in materials emission testing.

    PubMed

    Nohr, Michael; Horn, Wolfgang; Jann, Oliver; Richter, Matthias; Lorenz, Wilhelm

    2015-04-01

    Emission test chamber measurement is necessary to proof building materials as sources of volatile organic compounds (VOCs). The results of such measurements are used to evaluate materials and label them according to their potential to emit harmful substances, polluting indoor air. If only labelled materials were installed indoors, this would improve indoor air quality and prevent negative impacts on human health. Because of the complex testing procedure, reference materials for the quality assurance are mandatory. Currently, there is a lack of such materials because most building products show a broad variation of emissions even within one batch. A previous study indicates lacquers, mixed with volatile organic pollutants, as reproducible emission source for a wide range of substances. In the present study, the curing of the lacquer-VOC mixture inside micro-chambers was optimised. Therefore, the humidity and the chamber flow were varied. Typical indoor air pollutants with a wide range of volatilities, for example, styrene, n-hexadecane, dimethyl and dibutyl phthalate were selected. It turned out that, under optimised curing parameters inside the micro-chamber, their emission can be reproduced with variations of less than 10 %. With this, a next important step towards a reference material for emission testing was achieved. PMID:25543146

  1. FULL-SCALE VIBRATING PERVAPORATION MEMBRANE UNIT: VOC REMOVAL FROM WATER AND SURFACTANT SOLUTIONS

    EPA Science Inventory

    A commercial-scale vibrating membrane system with 10 square meters of membrane area was evaluated for the separation of volatile organic compounds (VOCs) from aqueous solutions by pervaporation. Experiments with surrogate solutions of up to five VOCs in the presence and absence o...

  2. Effect of wind tunnel air velocity on VOC flux rates from CAFO manure and wastewater

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wind tunnels and flux chambers are often used to estimate volatile organic compound (VOC) emissions from animal feeding operations (AFOs) without regard to air velocity or sweep air flow rates. Laboratory experiments were conducted to evaluate the effect of wind tunnel air velocity on VOC emission ...

  3. U.S.-MEXICO BORDER PROGRAM ARIZONA BORDER STUDY--VOCS IN WATER ANALYTICAL RESULTS

    EPA Science Inventory

    The VOCs in Water data set contains analytical results for measurements of up to 26 volatile organic compounds (VOCs) in 97 water samples over 61 households. Samples were collected at the tap and any additional drinking water source used extensively within each residence. The p...

  4. U.S.-MEXICO BORDER PROGRAM ARIZONA BORDER STUDY--VOCS IN BLOOD ANALYTICAL RESULTS

    EPA Science Inventory

    The VOCs in Blood data set contains analytical results for measurements of up to 12 volatile organic compounds (VOCs) in 86 blood samples over 86 households. Each sample was collected as a venous sample from the primary respondent within each household. The samples consisted of...

  5. FULL-SCALE VIBRATING PERVAPORATION MEMBRANE UNIT: VOC REMOVAL FROM WATER AND SURFACTANT SOLUTIONS

    EPA Science Inventory

    A commercial-scale vibrating membrane system was evaluated for the separation of volatile organic compounds (VOCs) from aqueous solutions by pervaporation. Experiments with surrogate solutions of up to five VOCs in the presence and absence of a surfactant were performed to compar...

  6. Source characterization of volatile organic compounds affecting the air quality in a coastal urban area of South Texas.

    PubMed

    Sanchez, Marciano; Karnae, Saritha; John, Kuruvilla

    2008-09-01

    Selected Volatile Organic Compounds (VOC) emitted from various anthropogenic sources including industries and motor vehicles act as primary precursors of ozone, while some VOC are classified as air toxic compounds. Significantly large VOC emission sources impact the air quality in Corpus Christi, Texas. This urban area is located in a semi-arid region of South Texas and is home to several large petrochemical refineries and industrial facilities along a busy ship-channel. The Texas Commission on Environmental Quality has setup two continuous ambient monitoring stations (CAMS 633 and 634) along the ship channel to monitor VOC concentrations in the urban atmosphere. The hourly concentrations of 46 VOC compounds were acquired from TCEQ for a comprehensive source apportionment study. The primary objective of this study was to identify and quantify the sources affecting the ambient air quality within this urban airshed. Principal Component Analysis/Absolute Principal Component Scores (PCA/APCS) was applied to the dataset. PCA identified five possible sources accounting for 69% of the total variance affecting the VOC levels measured at CAMS 633 and six possible sources affecting CAMS 634 accounting for 75% of the total variance. APCS identified natural gas emissions to be the major source contributor at CAMS 633 and it accounted for 70% of the measured VOC concentrations. The other major sources identified at CAMS 633 included flare emissions (12%), fugitive gasoline emissions (9%), refinery operations (7%), and vehicle exhaust (2%). At CAMS 634, natural gas sources were identified as the major source category contributing to 31% of the observed VOC. The other sources affecting this site included: refinery operations (24%), flare emissions (22%), secondary industrial processes (12%), fugitive gasoline emissions (8%) and vehicle exhaust (3%). PMID:19139530

  7. Source Characterization of Volatile Organic Compounds Affecting the Air Quality in a Coastal Urban Area of South Texas

    PubMed Central

    Sanchez, Marciano; Karnae, Saritha; John, Kuruvilla

    2008-01-01

    Selected Volatile Organic Compounds (VOC) emitted from various anthropogenic sources including industries and motor vehicles act as primary precursors of ozone, while some VOC are classified as air toxic compounds. Significantly large VOC emission sources impact the air quality in Corpus Christi, Texas. This urban area is located in a semi-arid region of South Texas and is home to several large petrochemical refineries and industrial facilities along a busy ship-channel. The Texas Commission on Environmental Quality has setup two continuous ambient monitoring stations (CAMS 633 and 634) along the ship channel to monitor VOC concentrations in the urban atmosphere. The hourly concentrations of 46 VOC compounds were acquired from TCEQ for a comprehensive source apportionment study. The primary objective of this study was to identify and quantify the sources affecting the ambient air quality within this urban airshed. Principal Component Analysis/Absolute Principal Component Scores (PCA/APCS) was applied to the dataset. PCA identified five possible sources accounting for 69% of the total variance affecting the VOC levels measured at CAMS 633 and six possible sources affecting CAMS 634 accounting for 75% of the total variance. APCS identified natural gas emissions to be the major source contributor at CAMS 633 and it accounted for 70% of the measured VOC concentrations. The other major sources identified at CAMS 633 included flare emissions (12%), fugitive gasoline emissions (9%), refinery operations (7%), and vehicle exhaust (2%). At CAMS 634, natural gas sources were identified as the major source category contributing to 31% of the observed VOC. The other sources affecting this site included: refinery operations (24%), flare emissions (22%), secondary industrial processes (12%), fugitive gasoline emissions (8%) and vehicle exhaust (3%). PMID:19139530

  8. Low VOC drying of lumber and wood panel products. Progress report No. 5

    SciTech Connect

    Wild, P.; Yan, Hui; Banerjee, S.

    1997-10-01

    This progress report summarizes three accomplishments in a study of low volatile organic compound (VOC) drying of lumber and wood panel products. A mathematical model for predicting moisture emissions from particle was constructed and is being extended to VOCs. VOCs emissions from drying boards show that VOCs appear to be evenly released from all surfaces. Preliminary results from monthly analyses of loblolly pines indicate that resin acids appear to decrease between March to August, and that no consistent trends are apparent for terpenes. 3 refs., 13 figs., 1 tab.

  9. Implementation of VOC source reduction practices in a manufactured house and in school classrooms

    SciTech Connect

    Hodgson, A.T.; Apte, M.G.; Shendell, D.G.; Beal, D.; McIlvaine, J.E.R.

    2002-01-01

    Detailed studies of a new manufactured house and four new industrialized relocatable school classrooms were conducted to determine the emission sources of formaldehyde and other VOCs and to identify and implement source reduction practices. Procedures were developed to generate VOC emission factors that allowed reasonably accurate predictions of indoor air VOC concentrations. Based on the identified sources of formaldehyde and other aldehydes, practices were developed to reduce the concentrations of these compounds in new house construction. An alternate ceiling panel reduced formaldehyde concentrations in the classrooms. Overall, the classrooms had relatively low VOC concentrations.

  10. Characterization of hazardous and odorous volatiles emitted from scented candles before lighting and when lit.

    PubMed

    Ahn, Jeong-Hyeon; Kim, Ki-Hyun; Kim, Yong-Hyun; Kim, Bo-Won

    2015-04-01

    Scented candles are known to release various volatile organic compounds (VOCs) including both pleasant aromas and toxic components both before lighting (off) and when lit (on). In this study, we explored the compositional changes of volatiles from scented candles under various settings to simulate indoor use. Carbonyl compounds and other VOCs emitted from six different candle types were analyzed under 'on/off' conditions. The six candle types investigated were: (1) Clean cotton (CT), (2) Floral (FL), (3) Kiwi melon (KW), (4) Strawberry (SB), (5) Vanilla (VN), and (6) Plain (PL). Although a large number of chemicals were released both before lighting and when lit, their profiles were noticeably distinguishable. Before lighting, various esters (n = 30) showed the most dominant emissions. When lit, formaldehyde was found to have the highest emission concentration of 2098 ppb (SB), 1022 ppb (CT), and 925 ppb (PL). In most lit scented candles, there was a general tendency to show increased concentrations of low boiling point compounds. For some scented candle products, the emission of volatiles occurred strongly both before lighting and when lit. For instance, in terms of TVOC (ppbC), the highest concentrations were observed from the KW product with their values of 12,742 (on) and 2766 ppbC (off). As such, the results suggest that certain scented candle products should act as potent sources of VOC emission in indoor environment, regardless of conditions--whether being lit or not. PMID:25588193

  11. Evaluation of total volatile organic compound emissions from adhesives based on chamber tests.

    PubMed

    Guo, H; Murray, F; Wilkinson, S

    2000-02-01

    In 1997, Homeswest in western Australia and Murdoch University developed a project to construct low-allergen houses (LAHs) in a newly developed suburb. Before the construction of LAHs, all potential volatile organic compound (VOC) emission materials used in LAHs are required to be measured to ensure that they are low total VOC (TVOC) emission materials. This program was developed based on this purpose. In recent times, the number of complaints about indoor air pollution caused by VOCs has increased. A number of surveys of indoor VOCs have indicated that many indoor materials contribute to indoor air pollution. Although some studies have been conducted on the characteristics of VOC emissions from adhesives, most of them were focused on VOC emissions from floor adhesives. Few measurements of VOC emissions from adhesives used for wood, fabrics, and leather are available. Furthermore, most research on VOC emissions from adhesives has been done in countries with cool climates, where ventilation rates in the indoor environment are lower than those in Mediterranean climates, due to energy conservation. VOCs emitted from adhesives have not been sufficiently researched to prepare an emission inventory to predict indoor air quality and to determine both exposure levels for the Australian population and the most appropriate strategies to reduce exposure. An environmental test chamber with controlled temperature, relative humidity, and airflow rate was used to evaluate emissions of TVOCs from three adhesives used frequently in Australia. The quantity of TVOC emissions was measured by a gas chromatography/flame ionization detector. The primary VOCs emitted from each adhesive were detected by gas chromatography/mass spectrometry. The temporal change of TVOC concentrations emitted from each adhesive was tested. A double-exponential equation was then developed to evaluate the characteristics of TVOC emissions from these three adhesives. With this double-exponential model, the

  12. [Correlation Analysis Between Characteristics of VOCs and Ozone Formation Potential in Summer in Nanjing Urban District].

    PubMed

    Yang, Xiao-xiao; Tang, Li-li; Zhang, Yun-jiang; Mu, Ying-feng; Wang, Ming; Chen, Wen-tai; Zhou, Hong-cang; Hua, Yan; Jiang, Rong-xin

    2016-02-15

    Volatile organic compounds (VOCs) is an important precursor of photochemical ozone pollution (O3) in the atmosphere. Their concentration variation directly affects the characteristics of the ozone pollution. The concentration, speciation of VOCs, ozone and its precursors in Nanjing were analyzed and measured using online gas detection systems in August 2013. VOCs/NOx discriminant method was used to get the sensitive control factors of ozone. The results showed that the averaged volume fraction of VOCs was 52. 05 x 10(-9), and the largest one reached 200 x 10(-9) in Nanjing urban district. The order of volume fraction of each species VOCs was alkane > oxygen-containing VOCs > alkene > aromatics. The averaged concentration of ozone was 76.5 microg x m(-1) and the exceeding concentration of hourly standard was 5.9%. The change trends of ozone precursors VOCs and NOx were basically identical and Ozone showed the obvious negative correlation during the period of high concentrations of ozone. There were some differences in the concentrations of the same VOCs in different ozone concentration periods. The ozone generation in Nanjing urban district was sensitive to VOCs, and Nanjing belonged to VOCs control area in summer. PMID:27363129

  13. Clinical Application of Volatile Organic Compound Analysis for Detecting Infectious Diseases

    PubMed Central

    Nanda, Ranjan; Chakraborty, Trinad

    2013-01-01

    SUMMARY This review article introduces the significance of testing of volatile organic compounds (VOCs) in clinical samples and summarizes important features of some of the technologies. Compared to other human diseases such as cancer, studies on VOC analysis in cases of infectious diseases are limited. Here, we have described results of studies which have used some of the appropriate technologies to evaluate VOC biomarkers and biomarker profiles associated with infections. The publications reviewed include important infections of the respiratory tract, gastrointestinal tract, urinary tract, and nasal cavity. The results highlight the use of VOC biomarker profiles resulting from certain infectious diseases in discriminating between infected and healthy subjects. Infection-related VOC profiles measured in exhaled breath as well as from headspaces of feces or urine samples are a source of information with respect to disease detection. The volatiles emitted in clinical matrices may on the one hand represent metabolites of the infecting pathogen or on the other hand reflect pathogen-induced host responses or, indeed, a combination of both. Because exhaled-breath samples are easy to collect and online instruments are commercially available, VOC analysis in exhaled breath appears to be a promising tool for noninvasive detection and monitoring of infectious diseases. PMID:23824368

  14. Global inventory of volatile organic compound emissions from anthropogenic sources

    SciTech Connect

    Piccot, S.D.; Watson, J.J.; Jones, J.W.

    1992-01-01

    The paper discusses the development of a global inventory of anthropogenic volatile organic compound (VOC) emissions. It includes VOC estimates for seven classes of VOCs: paraffins, olefins, aromatics (benzene, toluene, xylene), formaldehyde, other aldehydes, other aromatics, and marginally reactive compounds. These classes represent general classes of VOC compounds that possess different chemical reactivities in the atmosphere. The inventory shows total global anthropogenic VOC emissions of about 110,000 Gg/yr, about 10% lower than global VOC inventories developed by other researchers. The study identifies the U.S. as the largest emitter (21% of the total global VOC), followed by the USSR, China, India, and Japan. Globally, fuel wood combustion and savanna burning were among the largest VOC emission sources, accounting for over 35% of the total global VOC emissions. The production and use of gasoline, refuse disposal activities, and organic chemical and rubber manufacturing were also found to be significant sources of global VOC emissions.

  15. Significance of the Development of VOC Sensors

    NASA Astrophysics Data System (ADS)

    Matsubara, Ichiro; Itoh, Toshio; Murayama, Norimitsu

    The environmental problems relevant to VOC, such as sick house syndrome and air pollution, have attracted attention more and more. Japanese government has recently set forth the measure to VOC by amendments to related codes and regulations. The measurement technology and sensors for hazardous chemical substances, formaldehyde, toluene and xylene, are important to control the VOC level. The development of VOC sensors is desired because it is possible to measure VOC concentration simply and quickly, which makes it possible to realize the constant self-management of VOC and to check the real time change of VOC level. Since the performance requirements to a VOC sensor depend much on the applications, it is necessary to figure out the required specifications before starting the development of target VOC sensors. High performance VOC sensors applicable to many application fields are required to construct a secure and safe society.

  16. Clinical breath analysis: Discriminating between human endogenous compounds and exogenous (environmental) chemical confounders

    EPA Science Inventory

    Volatile organic compounds (VOCs) in exhaled breath originate from current or previous environmental exposures (exogenous compounds) and internal metabolic anabolic and catabolic) production (endogenous compounds). The origins of certain VOCs in breath presumed to be endogenous ...

  17. The Venus flytrap attracts insects by the release of volatile organic compounds

    PubMed Central

    Kreuzwieser, Jürgen; Honsel, Anne

    2014-01-01

    Does Dionaea muscipula, the Venus flytrap, use a particular mechanism to attract animal prey? This question was raised by Charles Darwin 140 years ago, but it remains unanswered. This study tested the hypothesis that Dionaea releases volatile organic compounds (VOCs) to allure prey insects. For this purpose, olfactory choice bioassays were performed to elucidate if Dionaea attracts Drosophila melanogaster. The VOCs emitted by the plant were further analysed by GC-MS and proton transfer reaction-mass spectrometry (PTR-MS). The bioassays documented that Drosophila was strongly attracted by the carnivorous plant. Over 60 VOCs, including terpenes, benzenoids, and aliphatics, were emitted by Dionaea, predominantly in the light. This work further tested whether attraction of animal prey is affected by the nutritional status of the plant. For this purpose, Dionaea plants were fed with insect biomass to improve plant N status. However, although such feeding altered the VOC emission pattern by reducing terpene release, the attraction of Drosophila was not affected. From these results it is concluded that Dionaea attracts insects on the basis of food smell mimicry because the scent released has strong similarity to the bouquet of fruits and plant flowers. Such a volatile blend is emitted to attract insects searching for food to visit the deadly capture organ of the Venus flytrap. PMID:24420576

  18. The Venus flytrap attracts insects by the release of volatile organic compounds.

    PubMed

    Kreuzwieser, Jürgen; Scheerer, Ursel; Kruse, Jörg; Burzlaff, Tim; Honsel, Anne; Alfarraj, Saleh; Georgiev, Plamen; Schnitzler, Jörg-Peter; Ghirardo, Andrea; Kreuzer, Ines; Hedrich, Rainer; Rennenberg, Heinz

    2014-02-01

    Does Dionaea muscipula, the Venus flytrap, use a particular mechanism to attract animal prey? This question was raised by Charles Darwin 140 years ago, but it remains unanswered. This study tested the hypothesis that Dionaea releases volatile organic compounds (VOCs) to allure prey insects. For this purpose, olfactory choice bioassays were performed to elucidate if Dionaea attracts Drosophila melanogaster. The VOCs emitted by the plant were further analysed by GC-MS and proton transfer reaction-mass spectrometry (PTR-MS). The bioassays documented that Drosophila was strongly attracted by the carnivorous plant. Over 60 VOCs, including terpenes, benzenoids, and aliphatics, were emitted by Dionaea, predominantly in the light. This work further tested whether attraction of animal prey is affected by the nutritional status of the plant. For this purpose, Dionaea plants were fed with insect biomass to improve plant N status. However, although such feeding altered the VOC emission pattern by reducing terpene release, the attraction of Drosophila was not affected. From these results it is concluded that Dionaea attracts insects on the basis of food smell mimicry because the scent released has strong similarity to the bouquet of fruits and plant flowers. Such a volatile blend is emitted to attract insects searching for food to visit the deadly capture organ of the Venus flytrap. PMID:24420576

  19. Treatment of munitions manufacturing airborne VOC`s by biofiltration

    SciTech Connect

    Severin, B.F.; Neilson, L.M.; Kim, B.J.

    1997-12-31

    The US Army Construction Engineering Research Laboratory contracted MBI International to perform a biofiltration study of industrial waste gas streams. Phase I of the study was a laboratory investigation of the treatability of a specific gas stream. The laboratory study was concluded in September, 1995. Phase II was the design, placement and operation of a full-scale biofilter. The project was completed in August, 1996. The specific gas stream originates from a munitions drying operation at the Olin Chemical Company, Lake City, AAP, Independence, MO. The production line is a blank bullet coating operation in the production line, slats of blank ammunition are inverted and dipped into a coating material to seal the shell tips. The slats are then righted and moved into a drying box. The major solvent in the coating is ethyl acetate (70%) with about 30% of other solvent, such as, xylene and low molecular weight alcohols. The coating is thinned 50% with ethyl acetate, such that ethyl acetate represents more than 90% of the VOC load. The concentration of VOC`s is 400 ug/L at an air flow rate of 1000 ft{sup 3}/min. Laboratory results were collected on six test biofilter columns (15L). Steady state operations over a wide range of VOC loads were studied. The biofilters consistently destroyed 90-95% of the VOC`s. Square-wave dynamic loading cycles were studied to represent shift changes at the production facility. At high loadings, the biofilter performed well. At low organic loadings at applications of 5 hr/day of the gas stream, the filters required a small supplement of glucose to maintain column efficacy. A 1000 cubic foot bed volume, engineered media, biofilter was installed at Lake City AAP in January, 1996. The unit consists of a skid-mounted, class-1 division-1 explosion proof design including the blower package, biofilter media, nutrient addition, and automated VOC monitoring with PID. The unit was monitored for six months.

  20. Organic compounds in PM 2.5 emitted from fireplace and woodstove combustion of typical Portuguese wood species

    NASA Astrophysics Data System (ADS)

    Gonçalves, Cátia; Alves, Célia; Fernandes, Ana Patrícia; Monteiro, Cristina; Tarelho, Luís; Evtyugina, Margarita; Pio, Casimiro

    2011-09-01

    The aim of this study is the further characterisation of PM 2.5 emissions from the residential wood combustion of common woods grown in Portugal. This new research extends to eight the number of biomass fuels studied and tries to understand the differences that the burning appliance (fireplace versus woodstove) and the combustion temperature (cold and hot start) have on emissions. Pinus pinaster (Maritime pine), Eucalyptus globulus (eucalypt), Quercus suber (cork oak), Acacia longifolia (Golden wattle), Quercus faginea (Portuguese oak), Olea europea (Olive), Quercus ilex rotundifolia (Holm oak) and briquettes produced from forest biomass waste were used in the combustion tests. Determinations included fine particle emission factors, carbonaceous content (OC and EC) by a thermal-optical transmission technique and detailed identification and quantification of organic compounds by gas chromatography-mass spectrometry. Fine particle emission factors from the woodstove were lower than those from the fireplace. For both combustion appliances, the OC/EC ratio was higher in "cold start" tests (1.56 ± 0.95 for woodstove and 2.03 ± 1.34 for fireplace). These "cold start" OC/EC values were, respectively, for the woodstove and the fireplace, 51% and 69% higher than those obtained in "hot start" experiments. The chromatographically resolved organics included n-alkanes, n-alkenes, PAHs, n-alkanals, ketones, n-alkanols, terpenoids, triterpenoids, phenolic compounds, phytosterols, alcohols, n-alkanoic acids, n-di-acids, unsaturated acids and alkyl esters of acids. The smoke emission rate and composition varied widely depending on fuel type, burning appliance and combustion temperature.

  1. NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR USE OF THE ACTIVE VOC SAMPLER FOR THE COLLECTION OF AIRBORNE VOCS AT FIXED INDOOR AND OUTDOOR SITES (UA-F-11.1)

    EPA Science Inventory

    The purpose of this SOP is to describe the methods used to collect indoor and outdoor air samples for the determination of selected volatile organic compounds (VOC's) using a pump to draw air through a Carbotrap Sampler. Volatile organic compounds (VOCs) present in the air are p...

  2. COMPETITIVE ADSORPTION OF VOCS AND BOMOXIC AND ANOXIC ENVIRONMENTS

    EPA Science Inventory

    The effect of the presence of molecular oxygen on the adsorption of volatile organic compounds (VOCS) in distilled Milli-Q water and in water supplemented with background organic matter (BOM) is evaluated. xperiments are conducted under conditions where molecular oxygen is presen...

  3. CANISTER-BASED METHODOLOGY FOR MONITORING OF AMBIENT TOXIC VOCS

    EPA Science Inventory

    The availability of reliable, accurate and precise monitoring methods for to:':ic volatile organic compounds (VOCs) is a primary need for state and local agencies addressing daily monitoring requirements related to odor complaints, fugitive emissions, and trend monitoring. The ca...

  4. ASSESSMENT OF EXISTING TEST REPORTS FOR EVALUATING VOC CONTROL EFFECTIVENESS

    EPA Science Inventory

    The report outlines the approach taken by EPA to review existing test reports for evaluating volatile organic compound (VOC) control device effectiveness and identifying missing control device effectiveness information. A format is presented to provide guidance and serve as the b...

  5. NARSTO PAC2001 CESSNA VOC PM OZONE MET DATA

    Atmospheric Science Data Center

    2014-04-25

    NARSTO PAC2001 CESSNA VOC PM OZONE MET DATA Project Title:  NARSTO Discipline:  ... Temperature Probe Humidity Probe Wind Sensor UV Ozone Detector Optical Counter GC Location:  Lower Fraser ... Air Temperature Humidity Upper Level Winds Ozone Aerosol Particle Properties Volatile Organic Compounds ...

  6. EVALUATION OF MAINTENANCE FOR FUGITIVE VOC EMISSIONS CONTROL

    EPA Science Inventory

    The U.S. EPA Office of Air Quality Planning and Standards (OAQPS) has the responsibility for formulating regulations for the control of fugitive emissions of volatile organic compounds (VOC). 'Fugitive emissions' generally refers to the diffuse release of vaporized hydrocarbon or...

  7. A model for predicting VOC emission from silage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Silage has been shown to be an important source of emissions of volatile organic compounds (VOCs), which are precursors to ground-level ozone. Measurements show that environmental conditions and silage properties influence emission rates, making it difficult to assess the contribution of silage to V...

  8. CASE STUDIES: LOW-VOC/HAP WOOD FURNITURE COATINGS

    EPA Science Inventory


    The report gives results of a study in which wood furniture manufacturing facilities were identified that had converted at least one of their primary coating steps to low-volatile organic compound (VOC)/hazardous Air pollutant (HAP) wood furniture coatings: high-solids, water...

  9. RESEARCH AND PRODUCT DEVELOPMENT OF LOW-VOC WOOD COATINGS

    EPA Science Inventory

    The report discusses a project, cofunded by the South Coast Air Quality Management District (SCAQMD) and the U.S. EPA, to develop a new, low volatile organic compound (VOC) wood coating. Traditional wood furniture coating technologies contain organic solvents which become air pol...

  10. ENVIRONMENTALLY SAFE, NO VOC AUTOMOTIVE COATING - PHASE II

    EPA Science Inventory

    The EPA recognizes that volatile organic compounds (VOCs) must be eliminated from automotive coating formulations to improve worker safety and reduce environmental pollution. The phase I project resulted in the production of a polymer-based coating material that was clear, ...

  11. Photocatalytic performance of cylindrical reactor inserted with UV light-emitting-diodes for purification of low-level toxic volatile organic compounds

    NASA Astrophysics Data System (ADS)

    Jo, Wan K.; Kang, Hyun J.

    2012-10-01

    The present study investigated the photocatalytic performance of a cylindrical reactor inserted with UV light-emitting-diodes for the decomposition of low-level (0.1 ppm) gas-phase organic compounds (benzene, toluene, ethyl benzene and xylene (BTEX)). The morphological and optical properties of photocatalysts (Degussa P-25 TiO2) baked at different temperatures were determined using a range of spectral instruments. The photocatalyst baked at 350 °C exhibited the highest conversion efficiencies for both benzene and toluene (81 and ∼100%, respectively). The conventional lamp showed a higher conversion efficiency for benzene compared to the 380-nm UV-LED and a higher conversion efficiency for benzene and toluene than the 365-nm UV-LED. However, the ratios of conversion efficiency to electric power consumption were 2.5-3.0 times higher for the latter light source than the former source. Moreover, as the residence time increased from 0.2 to 1.2 min, the average conversion efficiencies for BTEX of the 3-h photocatalytic process increased from nearly zero to 81%, 7 to nearly 100%, 20 to nearly 100%, and 29-30 to nearly 100%, respectively. The cylindrical photocatalytic reactor inserted with UV-LEDs could be energy-efficiently applied for the decomposition of low-level toxic compounds after optimization of the operating conditions.

  12. Development of new VOC exposure metrics and their relationship to ''Sick Building Syndrome'' symptoms

    SciTech Connect

    Ten Brinke, JoAnn

    1995-08-01

    Volatile organic compounds (VOCs) are suspected to contribute significantly to ''Sick Building Syndrome'' (SBS), a complex of subchronic symptoms that occurs during and in general decreases away from occupancy of the building in question. A new approach takes into account individual VOC potencies, as well as the highly correlated nature of the complex VOC mixtures found indoors. The new VOC metrics are statistically significant predictors of symptom outcomes from the California Healthy Buildings Study data. Multivariate logistic regression analyses were used to test the hypothesis that a summary measure of the VOC mixture, other risk factors, and covariates for each worker will lead to better prediction of symptom outcome. VOC metrics based on animal irritancy measures and principal component analysis had the most influence in the prediction of eye, dermal, and nasal symptoms. After adjustment, a water-based paints and solvents source was found to be associated with dermal and eye irritation. The more typical VOC exposure metrics used in prior analyses were not useful in symptom prediction in the adjusted model (total VOC (TVOC), or sum of individually identified VOCs ({Sigma}VOC{sub i})). Also not useful were three other VOC metrics that took into account potency, but did not adjust for the highly correlated nature of the data set, or the presence of VOCs that were not measured. High TVOC values (2--7 mg m{sup {minus}3}) due to the presence of liquid-process photocopiers observed in several study spaces significantly influenced symptoms. Analyses without the high TVOC values reduced, but did not eliminate the ability of the VOC exposure metric based on irritancy and principal component analysis to explain symptom outcome.

  13. Impacts of simulated herbivory on VOC emission profiles from coniferous plants

    DOE PAGESBeta

    Faiola, C. L.; Jobson, B. T.; VanReken, T. M.

    2014-09-18

    The largest global source of volatile organic compounds (VOCs) in the atmosphere is from biogenic emissions. Plant stressors associated with a changing environment can alter both the quantity and composition of the compounds that are emitted. This study investigated the effects of one global change stressor, increased herbivory, on plant emissions from five different coniferous species: bristlecone pine (Pinus aristata), blue spruce (Picea pungens), western redcedar (Thuja plicata), grand fir (Abies grandis), and Douglas-fir (Pseudotsugas menziesii). Herbivory was simulated in the laboratory via exogenous application of methyl jasmonate, an herbivory proxy. Gas-phase species were measured continuously with a gas chromatographmore » coupled to a mass spectrometer and flame ionization detector (GC-MS-FID). Stress responses varied between the different plant types and even between experiments using the same set of saplings. The compounds most frequently impacted by the stress treatment were alpha-pinene, beta-pinene, 1,8-cineol, beta-myrcene, terpinolene, limonene, and the cymene isomers. Individual compounds within a single experiment often exhibited a different response to the treatment from one another.« less

  14. Impacts of simulated herbivory on VOC emission profiles from coniferous plants

    NASA Astrophysics Data System (ADS)

    Faiola, C. L.; Jobson, B. T.; VanReken, T. M.

    2014-09-01

    The largest global source of volatile organic compounds (VOCs) in the atmosphere is from biogenic emissions. Plant stressors associated with a changing environment can alter both the quantity and composition of the compounds that are emitted. This study investigated the effects of one global change stressor, increased herbivory, on plant emissions from five different coniferous species: bristlecone pine (Pinus aristata), blue spruce (Picea pungens), western redcedar (Thuja plicata), grand fir (Abies grandis), and Douglas-fir (Pseudotsugas menziesii). Herbivory was simulated in the laboratory via exogenous application of methyl jasmonate, an herbivory proxy. Gas-phase species were measured continuously with a gas chromatograph coupled to a mass spectrometer and flame ionization detector (GC-MS-FID). Stress responses varied between the different plant types and even between experiments using the same set of saplings. The compounds most frequently impacted by the stress treatment were alpha-pinene, beta-pinene, 1,8-cineol, beta-myrcene, terpinolene, limonene, and the cymene isomers. Individual compounds within a single experiment often exhibited a different response to the treatment from one another.

  15. Emissions of oxygenated volatile organic compounds from open crop burning in Yangtze River Delta region, China

    NASA Astrophysics Data System (ADS)

    Tanimoto, H.; Kudo, S.; Pan, X.; Inomata, S.; Saito, S.; Kanaya, Y.; Wang, Z.

    2013-12-01

    Measurements of volatile organic compounds (VOCs) were made by gas chromatography/flame ionization detection/mass spectrometry (GC/FID/MS) and proton transfer reaction-mass spectrometry (PTR-MS) at Rudong, a rural area of Central East China in June 2010. During the campaign we identified several plumes originated from open biomass burning by the simultaneous enhancements of carbon monoxide and acetonitrile. Based on positive matrix factorization (PMF) analysis, the contribution of biomass burning was in the range from 60 to 80% for the plumes. We found that oxygenated VOCs were predominant for these events. The emission ratios of OVOCs to CO for open crop burnings derived in this work were found to be high. Combined with the updated CO emissions of 12.7 Tg per year from crop burning, we estimated OVOC emissions from crop burning can be about 1.2 Tg per year, accounting for substantial amount of VOCs emitted from crop burning.

  16. Analysis of Plant Growth-Promoting Effects of Fluorescent Pseudomonas Strains Isolated from Mentha piperita Rhizosphere and Effects of Their Volatile Organic Compounds on Essential Oil Composition.

    PubMed

    Santoro, Maricel V; Bogino, Pablo C; Nocelli, Natalia; Cappellari, Lorena Del Rosario; Giordano, Walter F; Banchio, Erika

    2016-01-01

    Many species or strains of the genus Pseudomonas have been characterized as plant growth promoting rhizobacteria (PGPR). We used a combination of phenotypic and genotypic techniques to analyze the community of fluorescent Pseudomonas strains in the rhizosphere of commercially grown Mentha piperita (peppermint). Biochemical techniques, Amplified rDNA Restriction Analysis (ARDRA), and 16S rRNA gene sequence analysis revealed that the majority of the isolated native fluorescent strains were P. putida. Use of two Repetitive Sequence-based PCR (rep-PCR) techniques, BOX-PCR and ERIC-PCR, allowed us to evaluate diversity among the native strains and to more effectively distinguish among them. PGPR activity was tested for the native strains and reference strain P. fluorescens WCS417r. Micropropagated M. piperita plantlets were exposed to microbial volatile organic compounds (mVOCs) emitted by the bacterial strains, and plant biomass parameters and production of essential oils (EOs) were measured. mVOCs from 11 of the native strains caused an increase in shoot fresh weight. mVOCs from three native strains (SJ04, SJ25, SJ48) induced changes in M. pierita EO composition. The mVOCs caused a reduction of metabolites in the monoterpene pathway, for example menthofuran, and an increase in menthol production. Menthol production is the primary indicator of EO quality. The mVOCs produced by native strains SJ04, SJ25, SJ48, and strain WCS417r were analyzed. The obtained mVOC chromatographic profiles were unique for each of the three native strains analyzed, containing varying hydrocarbon, aromatic, and alogenic compounds. The differential effects of the strains were most likely due to the specific mixtures of mVOCs emitted by each strain, suggesting a synergistic effect occurs among the compounds present. PMID:27486441

  17. Analysis of Plant Growth-Promoting Effects of Fluorescent Pseudomonas Strains Isolated from Mentha piperita Rhizosphere and Effects of Their Volatile Organic Compounds on Essential Oil Composition

    PubMed Central

    Santoro, Maricel V.; Bogino, Pablo C.; Nocelli, Natalia; Cappellari, Lorena del Rosario; Giordano, Walter F.; Banchio, Erika

    2016-01-01

    Many species or strains of the genus Pseudomonas have been characterized as plant growth promoting rhizobacteria (PGPR). We used a combination of phenotypic and genotypic techniques to analyze the community of fluorescent Pseudomonas strains in the rhizosphere of commercially grown Mentha piperita (peppermint). Biochemical techniques, Amplified rDNA Restriction Analysis (ARDRA), and 16S rRNA gene sequence analysis revealed that the majority of the isolated native fluorescent strains were P. putida. Use of two Repetitive Sequence-based PCR (rep-PCR) techniques, BOX-PCR and ERIC-PCR, allowed us to evaluate diversity among the native strains and to more effectively distinguish among them. PGPR activity was tested for the native strains and reference strain P. fluorescens WCS417r. Micropropagated M. piperita plantlets were exposed to microbial volatile organic compounds (mVOCs) emitted by the bacterial strains, and plant biomass parameters and production of essential oils (EOs) were measured. mVOCs from 11 of the native strains caused an increase in shoot fresh weight. mVOCs from three native strains (SJ04, SJ25, SJ48) induced changes in M. pierita EO composition. The mVOCs caused a reduction of metabolites in the monoterpene pathway, for example menthofuran, and an increase in menthol production. Menthol production is the primary indicator of EO quality. The mVOCs produced by native strains SJ04, SJ25, SJ48, and strain WCS417r were analyzed. The obtained mVOC chromatographic profiles were unique for each of the three native strains analyzed, containing varying hydrocarbon, aromatic, and alogenic compounds. The differential effects of the strains were most likely due to the specific mixtures of mVOCs emitted by each strain, suggesting a synergistic effect occurs among the compounds present. PMID:27486441

  18. Study of the effect of biogenic VOC emissions on regional ozone production and the implications for VOC or NO{sub x} control

    SciTech Connect

    Stockwell, W.R.; Kuhn, M.

    1998-12-31

    A key question for the development of air pollution control strategies is whether to reduce nitrogen oxides (NO{sub x}) or volatile organic compound (VOC) emissions. Significant levels of biogenic VOC emissions may greatly limit the effectiveness of VOC control strategies. Concerns have been raised because for many cities it has been suggested that biogenic emissions are a dominate source of VOCs. Biogenic emissions would be expected to contribute an even larger fraction of the VOC emissions on the regional scale than within urban areas. The authors used a new atmospheric chemistry mechanism, the Regional Atmospheric Chemistry Mechanism (RACM), to perform ozone reactivity calculations to investigate the effects of biogenic emissions on the production of photooxidants in the atmosphere. The results show that incremental reactivity of isoprene is about the same as xylene and that the incremental reactivities of d-limonene and a-pinene are near those of toluene.

  19. Non-thermal Plasma for VOC Treatment in Flue Gases

    NASA Astrophysics Data System (ADS)

    Ikaunieks, Janis; Mezmale, Liga; Zandeckis, Aivars; Pubule, Jelena; Blumberga, Andra; Veidenbergs, Ivars

    2011-01-01

    The paper discusses non-thermal plasmas, their generation and characteristics, formation mechanisms of ozone and the treatment of volatile organic compounds (VOCs). In the experimental part, undecane (C11H24 as model VOCs) was treated with assistance of low temperature plasma at an atmospheric pressure which was generated in the so-called stack reactor. The gas composition was 13% of oxygen in nitrogen with impurities of carbon dioxide, carbon monoxide and undecane. The formation of by-products, as well as the removal efficiency, were investigated.

  20. Annual cycle of volatile organic compound exchange between a boreal pine forest and the atmosphere

    NASA Astrophysics Data System (ADS)

    Rantala, P.; Aalto, J.; Taipale, R.; Ruuskanen, T. M.; Rinne, J.

    2015-06-01

    Long-term flux measurements of volatile organic compounds (VOC) over boreal forests are rare, although the forests are known to emit considerable amounts of VOCs into the atmosphere. Thus, we measured fluxes of several VOCs and oxygenated VOCs over a Scots pine dominated boreal forest semi-continuously between May 2010 and December 2013. The VOC profiles were obtained with a proton-transfer-reaction mass-spectrometry, and the fluxes were calculated using vertical concentration profiles and the surface layer profile method connected to the Monin-Obukhov similarity theory. In total fluxes that differed significantly from zero on a monthly basis were observed for 14 out 27 measured masses. Monoterpenes had the highest net emission in all seasons and statistically significant positive fluxes were detected from March until November. Other important compounds emitted were methanol, ethanol/formic acid, acetone and isoprene/MBO. Oxygenated VOCs showed also deposition fluxes that were statistically different from zero. Isoprene/methylbutenol and monoterpene fluxes followed well the traditional isoprene algorithm and the hybrid algorithm, respectively. Emission potentials of monoterpenes were largest in late spring and fall which was possibly driven by growth processes and decaying of soil litter, respectively. Conversely, largest emission potentials of isoprene/methylbutenol were found in July. Thus, we concluded that most of the emissions of m/z 69 at the site consisted of isoprene that originated from broadleaved trees. Methanol had deposition fluxes especially before sunrise. This can be connected to water films on surfaces. Based on this assumption, we were able to build an empirical algorithm for bi-directional methanol exchange that described both emission term and deposition term. Methanol emissions were highest in May and June and deposition level increased towards fall, probably as a result of increasing relative humidity levels leading to predominance of

  1. Seasonal cycles of biogenic volatile organic compound fluxes and concentrations in a California citrus orchard

    NASA Astrophysics Data System (ADS)

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

    2012-07-01

    Orange trees are widely cultivated in Mediterranean climatic regions where they are an important agricultural crop. Citrus have been characterized as emitters of volatile organic compounds (VOC) in chamber studies under controlled environmental conditions, but an extensive characterization at field scale has never been performed using modern measurement methods, and is particularly needed considering the complex interactions between the orchards and the polluted atmosphere in which Citrus is often cultivated. For one year, in a Valencia orange orchard in Exeter, California, we measured fluxes using PTRMS (Proton Transfer Reaction Mass Spectrometer) and eddy covariance for the most abundant VOC typically emitted from citrus vegetation: methanol, acetone, and isoprenoids. Concentration gradients of additional oxygenated and aromatic compounds from the ground level to above the canopy were also measured. In order to characterize concentrations of speciated biogenic VOC (BVOC) in leaves, we analyzed leaf content by GC-MS (Gas Chromatography-Mass Spectrometery) regularly throughout the year. We also characterize in more detail concentrations of speciated BVOC in the air above the orchard by in-situ GC-MS during a few weeks in spring flowering and summer periods. Here we report concentrations and fluxes of the main VOC species emitted by the orchard, discuss how fluxes measured in the field relate to previous studies made with plant enclosures, and describe how VOC content in leaves and emissions change during the year in response to phenological and environmental parameters. The orchard was a source of monoterpenes and oxygenated VOC. The highest emissions were observed during the springtime flowering period, with mid-day fluxes above 2 nmol m-2 s-1 for methanol and up to 1 nmol m-2 s-1 for acetone and monoterpenes. During hot summer days emissions were not as high as we expected considering the known dependence of biogenic emissions on temperature. We provide evidence

  2. Seasonal cycles of biogenic volatile organic compound fluxes and concentrations in a California citrus orchard

    NASA Astrophysics Data System (ADS)

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

    2012-10-01

    Orange trees are widely cultivated in Mediterranean climatic regions where they are an important agricultural crop. Citrus have been characterized as emitters of volatile organic compounds (VOC) in chamber studies under controlled environmental conditions, but an extensive characterization at field scale has never been performed using modern measurement methods, and is particularly needed considering the complex interactions between the orchards and the polluted atmosphere in which Citrus is often cultivated. For one year, in a Valencia orange orchard in Exeter, California, we measured fluxes using PTRMS (Proton Transfer Reaction Mass Spectrometer) and eddy covariance for the most abundant VOC typically emitted from citrus vegetation: methanol, acetone, and isoprenoids. Concentration gradients of additional oxygenated and aromatic compounds from the ground level to above the canopy were also measured. In order to characterize concentrations of speciated biogenic VOC (BVOC) in leaves, we analyzed leaf content by GC-MS (Gas Chromatography - Mass Spectrometery) regularly throughout the year. We also characterized in more detail concentrations of speciated BVOC in the air above the orchard by in-situ GC-MS during a few weeks in spring flowering and summer periods. Here we report concentrations and fluxes of the main VOC species emitted by the orchard, discuss how fluxes measured in the field relate to previous studies made with plant enclosures, and describe how VOC content in leaves and emissions change during the year in response to phenological and environmental parameters. The orchard was a source of monoterpenes and oxygenated VOC. The highest emissions were observed during the springtime flowering period, with mid-day fluxes above 2 nmol m-2 s-1 for methanol and up to 1 nmol m-2 s-1 for acetone and monoterpenes. During hot summer days emissions were not as high as we expected considering the known dependence of biogenic emissions on temperature. We provide

  3. Annual cycle of volatile organic compound exchange between a boreal pine forest and the atmosphere

    NASA Astrophysics Data System (ADS)

    Rantala, P.; Aalto, J.; Taipale, R.; Ruuskanen, T. M.; Rinne, J.

    2015-10-01

    Long-term flux measurements of volatile organic compounds (VOC) over boreal forests are rare, although the forests are known to emit considerable amounts of VOCs into the atmosphere. Thus, we measured fluxes of several VOCs and oxygenated VOCs over a Scots-pine-dominated boreal forest semi-continuously between May 2010 and December 2013. The VOC profiles were obtained with a proton transfer reaction mass spectrometry, and the fluxes were calculated using vertical concentration profiles and the surface layer profile method connected to the Monin-Obukhov similarity theory. In total fluxes that differed significantly from zero on a monthly basis were observed for 13 out of 27 measured masses. Monoterpenes had the highest net emission in all seasons and statistically significant positive fluxes were detected from March until October. Other important compounds emitted were methanol, ethanol+formic acid, acetone and isoprene+methylbutenol. Oxygenated VOCs showed also deposition fluxes that were statistically different from zero. Isoprene+methylbutenol and monoterpene fluxes followed well the traditional isoprene algorithm and the hybrid algorithm, respectively. Emission potentials of monoterpenes were largest in late spring and autumn which was possibly driven by growth processes and decaying of soil litter, respectively. Conversely, largest emission potentials of isoprene+methylbutenol were found in July. Thus, we concluded that most of the emissions of m/z 69 at the site consisted of isoprene that originated from broadleaved trees. Methanol had deposition fluxes especially before sunrise. This can be connected to water films on surfaces. Based on this assumption, we were able to build an empirical algorithm for bi-directional methanol exchange that described both emission term and deposition term. Methanol emissions were highest in May and June and deposition level increased towards autumn, probably as a result of increasing relative humidity levels leading to

  4. Biogenic volatile organic compounds - small is beautiful

    NASA Astrophysics Data System (ADS)

    Owen, S. M.; Asensio, D.; Li, Q.; Penuelas, J.

    2012-12-01

    degradation rate in soil of the persistant organic pollutants, likely acting as analogues for the cometabo-lism of polychlorinated biphenyls (PCBs) Flowers of a ginger species (Alpinia kwangsiensis) and a fig species (Ficus hispida) showed different bVOC signals pre- and post pollination. For Ficus hispida, there are three floral stages of a fig-wasp dependency mechanism: receptive, post pollinator and interfloral. Of 28 compounds detected, transcaryophyllene with trans-β-farnesene were the most important at the receptor stage, trans-caryophyllene was the most abundant at the post-pollinator stage, and isoprene was the most abundant in the interfloral stage. Alpinia kwangsiensis presents two morphologies for the reproductive parts of the flower. The "anaflexistyle" morphology has the flower style lowered in the morning and raised in the afternoon. This is reversed for the "cataflexistyle" morphology. The bVOC mixture emitted by each morphology in morning and afternoon was complex. However for compounds showing a difference (cis-ocimene and Z + E epoxy -ocimene), the emissions from the anaflexistyle were greater than from the cataflexistyle, and were greater in the afternoon compared with the morning emissions. Where large flowering plant species are abundant, big changes in monoterpene emissions at < 2m above ground level over relatively small periods of time during pollination are likely to be missed in larger scale integrated flux measurements.

  5. NHEXAS PHASE I REGION 5 STUDY--VOCS IN BLOOD ANALYTICAL RESULTS

    EPA Science Inventory

    This data set includes analytical results for measurements of VOCs (volatile organic compounds) in 145 blood samples. These samples were collected to examine the relationships between personal exposure measurements, environmental measurements, and body burden. Venous blood sample...

  6. EVALUATION AND PERFORMANCE ASSESSMENT OF INNOVATIVE LOW-VOC CONTACT ADHESIVES IN WOOD LAMINATING OPERATIONS

    EPA Science Inventory

    The report gives results of an evaluation and assessment of the perfor-mance, economics, and emission reduction potential upon application of low-volatile organic compound (VOC) waterborne contact adhesive formulations specifically ina manual laminating operation for assembling s...

  7. EMERGING TECHNOLOGY BULLETIN: A CROSS-FLOW PERVAPORATION SYSTEM FOR REMOVAL OF VOCS FROM CONTAMINATED WASTEWATER

    EPA Science Inventory

    Pervaporation is a process for removing volatile organic compounds (VOC) from contaminated water. The performance of the cross-flow pervaporation system increases with temperature, with an equipment limitation of 35 degrees Celsius. Permeable membranes that preferentially adsor...

  8. MEASUREMENT OF VOCS DESORBED FROM BUILDING MATERIALS--A HIGH TEMPERATURE DYNAMIC CHAMBER METHOD

    EPA Science Inventory

    Mass balance is a commonly used approach for characterizing the source and sink behavior of building materials. Because the traditional sink test methods evaluate the adsorption and desorption of volatile organic compounds (VOC) at ambient temperatures, the desorption process is...

  9. BREATH MEASUREMENT AND MODELS TO ASSESS VOC DERMAL ABSORPTION IN WATER

    EPA Science Inventory

    Dermal exposure to volatile organic compounds (VOCs) in water results from environmental contamination of surface, ground-, and drinking waters. This exposure occurs both in occupational and residential settings. Compartmental models incorporating body burden measurements have ...

  10. Abiotic formation of volatile organic compounds from plant biomass and its dependence on temperature and UV radiation

    NASA Astrophysics Data System (ADS)

    Derendorp, L.; Holzinger, R.; Röckmann, T.

    2009-04-01

    The emissions of volatile organic compounds (VOCs) from living vegetation are measured for many different plant species. However, almost no research has been performed on the VOC emissions from plant litter and senescent leaves. The few studies that are done on plant litter indicate that the VOC emissions from this material can be significant for atmospheric chemistry and the global budgets of those VOCs. Recently, research showed that methane is emitted from dead and senescent leaves, and that the emission rates are influenced by temperature and ultraviolet (UV) radiation. It is also observed that not only methane, but also ethane and ethylene were emitted from leaf material under the influence of UV radiation. In this study, the emissions of ethane, ethylene, acetylene, propane, propylene, i-butane, n-butane and methyl chloride are measured with a gas chromatograph with a flame ionization detector. The effect of temperature and UV radiation on the emission rates of the different VOCs is measured for leaves of several plant species. The emission rates of ethane, ethylene, propane, propylene, and methylchloride increased exponentially with increasing temperature for all measured plant species, while a linear increase of the emission rates was observed for increasing intensity of the UV radiation. Emissions of acetylene, i-butane, and n-butane were not observed.

  11. Transport, behavior, and fate of volatile organic compounds in streams

    USGS Publications Warehouse

    Rathbun, R.E.

    1998-01-01

    Volatile organic compounds (VOCs) are compounds with chemical and physical properties that allow the compounds to move freely between the water and air phases of the environment. VOCs are widespread in the environment because of this mobility. Many VOCs have properties making them suspected or known hazards to the health of humans and aquatic organisms. Consequently, understanding the processes affecting the concentration and distribution VOCs in the environment is necessary. The U.S. Geological Survey selected 55 VOCs for study. This report reviews the characteristics of the various process that could affect the transport, behavior, and fate of these VOCs in streams.

  12. Studies of the Atmospheric Chemsitry of Energy-Related Volatile Organic Compounds and of their Atmospheric Reaction Products

    SciTech Connect

    Roger Atkinson; Janet Arey

    2007-04-14

    The focus of this contract was to investigate selected aspects of the atmospheric chemistry of volatile organic compounds (VOCs) emitted into the atmosphere from energy-related sources as well as from biogenic sources. The classes of VOCs studied were polycyclic aromatic hydrocarbons (PAHs) and nitro-PAHs, the biogenic VOCs isoprene, 2-methyl-3-buten-2-ol and cis-3-hexen-1-ol, alkenes (including alkenes emitted from vegetation) and their oxygenated atmospheric reaction products, and a series of oxygenated carbonyl and hydroxycarbonyl compounds formed as atmospheric reaction products of aromatic hydrocarbons and other VOCs. Large volume reaction chambers were used to investigate the kinetics and/or products of photolysis and of the gas-phase reactions of these organic compounds with hydroxyl (OH) radicals, nitrate (NO3) radicals, and ozone (O3), using an array of analytical instrumentation to analyze the reactants and products (including gas chromatography, in situ Fourier transform infrared spectroscopy, and direct air sampling atmospheric pressure ionization tandem mass spectrometry). The following studies were carried out. The photolysis rates of 1- and 2-nitronaphthalene and of eleven isomeric methylnitronaphthalenes were measured indoors using blacklamp irradiation and outdoors using natural sunlight. Rate constants were measured for the gas-phase reactions of OH radicals, Cl atoms and NO3 radicals with naphthalene, 1- and 2-methylnaphthalene, 1- and 2-ethylnaphthalene and the ten dimethylnaphthalene isomers. Rate constants were measured for the gas-phase reactions of OH radicals with four unsaturated carbonyls and with a series of hydroxyaldehydes formed as atmospheric reaction products of other VOCs, and for the gas-phase reactions of O3 with a series of cycloalkenes. Products of the gas-phase reactions of OH radicals and O3 with a series of biogenically emitted VOCs were identified and quantified. Ambient atmospheric measurements of the concentrations of a

  13. NEW SOIL VOC SAMPLERS: EN CORE AND ACCU CORE SAMPLING/STORAGE DEVICES FOR VOC ANALYSIS

    SciTech Connect

    Susan S. Sorini; John F. Schabron; Joseph F. Rovani Jr

    2006-06-01

    Soil sampling and storage practices for volatile organic analysis must be designed to minimize loss of volatile organic compounds (VOCs) from samples. The En Core{reg_sign} sampler is designed to collect and store soil samples in a manner that minimizes loss of contaminants due to volatilization and/or biodegradation. An ASTM International (ASTM) standard practice, D 6418, Standard Practice for Using the Disposable En Core Sampler for Sampling and Storing Soil for Volatile Organic Analysis, describes use of the En Core sampler to collect and store a soil sample of approximately 5 grams or 25 grams for volatile organic analysis and specifies sample storage in the En Core sampler at 4 {+-} 2 C for up to 48 hours; -7 to -21 C for up to 14 days; or 4 {+-} 2 C for up to 48 hours followed by storage at -7 to -21 C for up to five days. This report discusses activities performed during the past year to promote and continue acceptance of the En Core samplers based on their performance to store soil samples for VOC analysis. The En Core sampler is designed to collect soil samples for VOC analysis at the soil surface. To date, a sampling tool for collecting and storing subsurface soil samples for VOC analysis is not available. Development of a subsurface VOC sampling/storage device was initiated in 1999. This device, which is called the Accu Core{trademark} sampler, is designed so that a soil sample can be collected below the surface using a dual-tube penetrometer and transported to the laboratory for analysis in the same container. Laboratory testing of the current Accu Core design shows that the device holds low-level concentrations of VOCs in soil samples during 48-hour storage at 4 {+-} 2 C and that the device is ready for field evaluation to generate additional performance data. This report discusses a field validation exercise that was attempted in Pennsylvania in 2004 and activities being performed to plan and conduct a field validation study in 2006. A draft ASTM

  14. Volatile organic compound emissions from green waste composting: Characterization and ozone formation

    NASA Astrophysics Data System (ADS)

    Kumar, Anuj; Alaimo, Christopher P.; Horowitz, Robert; Mitloehner, Frank M.; Kleeman, Michael J.; Green, Peter G.

    2011-04-01

    Composting of green waste separated from the disposed solid waste stream reduces biodegradable inputs into landfills, and contributes valuable soil amendments to agriculture. Agencies in regions with severe air quality challenges, such as California's San Joaquin Valley (SJV), have raised concerns about gases emitted during the composting process, which are suspected to contribute to persistent high levels of ground-level ozone formation. The goal of the current study is to thoroughly characterize volatile organic compound (VOC) emissions from green waste compost piles of different ages (fresh tipped piles, 3-6 day old windrows, and 2-3 week old windrows). Multiple sampling and analytical approaches were applied to ensure the detection of most gaseous organic components emitted. More than 100 VOCs were detected and quantified in this study, including aliphatic alkanes, alkenes, aromatic hydrocarbons, biogenic organics, aldehydes, ketones, alcohols, furans, acids, esters, ether, halogenated hydrocarbons and dimethyl disulfide (DMDS). Alcohols were found to be the dominating VOC in the emissions from a compost pile regardless of age, with fluxes ranging from 2.6 to 13.0 mg m -2 min -1 with the highest emissions coming from the younger composting windrows (3-6 days). Average VOC emissions other than alcohols were determined to be 2.3 mg m -2 min -1 from younger windows, which was roughly two times higher than either the fresh tipping pile (1.2 mg m -2 min -1) or the older windrows (1.4 mg m -2 min -1). It was also observed that the older windrows emit a slightly larger proportion of more reactive compounds. Approximately 90% of the total VOCs were found to have maximum incremental reactivity of less than 2. Net ozone formation potential of the emissions was also assessed.

  15. FEV manoeuvre induced changes in breath VOC compositions: an unconventional view on lung function tests

    PubMed Central

    Sukul, Pritam; Schubert, Jochen K.; Oertel, Peter; Kamysek, Svend; Taunk, Khushman; Trefz, Phillip; Miekisch, Wolfram

    2016-01-01

    Breath volatile organic compound (VOC) analysis can open a non-invasive window onto pathological and metabolic processes in the body. Decades of clinical breath-gas analysis have revealed that changes in exhaled VOC concentrations are important rather than disease specific biomarkers. As physiological parameters, such as respiratory rate or cardiac output, have profound effects on exhaled VOCs, here we investigated VOC exhalation under respiratory manoeuvres. Breath VOCs were monitored by means of real-time mass-spectrometry during conventional FEV manoeuvres in 50 healthy humans. Simultaneously, we measured respiratory and hemodynamic parameters noninvasively. Tidal volume and minute ventilation increased by 292 and 171% during the manoeuvre. FEV manoeuvre induced substance specific changes in VOC concentrations. pET-CO2 and alveolar isoprene increased by 6 and 21% during maximum exhalation. Then they decreased by 18 and 37% at forced expiration mirroring cardiac output. Acetone concentrations rose by 4.5% despite increasing minute ventilation. Blood-borne furan and dimethyl-sulphide mimicked isoprene profile. Exogenous acetonitrile, sulphides, and most aliphatic and aromatic VOCs changed minimally. Reliable breath tests must avoid forced breathing. As isoprene exhalations mirrored FEV performances, endogenous VOCs might assure quality of lung function tests. Analysis of exhaled VOC concentrations can provide additional information on physiology of respiration and gas exchange. PMID:27311826

  16. VOC-Induced Flexing of Single and Multilayer Polyethylene Films As Gas Sensors.

    PubMed

    Alipour, Nazanin; Andersson, Richard L; Olsson, Richard T; Gedde, Ulf W; Hedenqvist, Mikael S

    2016-04-20

    The differential swelling and bending of multilayer polymeric films due to the dissimilar uptake of volatile organic compounds (VOCs; n-hexane, limonene) in the different layers was studied. Motions of thin polyethylene films triggered by the penetrant were investigated to learn more about how their deformation is related to VOC absorption. Single layers of metallocene or low-density polyethylene, and multilayers (2-288 layers) of these in alternating positions were considered. Single-, 24-, and 288-layer films displayed no motion when uniformly subjected to VOCs, but they could display simple curving modes when only one side of the film was wetted with a liquid VOC. Two-layer films displayed simple bending when uniformly subjected to VOCs due to the different swelling in the two layers, but when the VOC was applied to only one side of the film, more complex modes of motion as well as dynamic oscillations were observed (e.g., constant amplitude wagging at 2 Hz for ca. 50 s until all the VOC had evaporated). Diffusion modeling was used to study the transport behavior of VOCs inside the films and the different bending modes. Finally a prototype VOC sensor was developed, where the reproducible curving of the two-layer film was calibrated with n-hexane. The sensor is simple, cost-efficient, and nondestructive and requires no electricity. PMID:27023792

  17. FEV manoeuvre induced changes in breath VOC compositions: an unconventional view on lung function tests

    NASA Astrophysics Data System (ADS)

    Sukul, Pritam; Schubert, Jochen K.; Oertel, Peter; Kamysek, Svend; Taunk, Khushman; Trefz, Phillip; Miekisch, Wolfram

    2016-06-01

    Breath volatile organic compound (VOC) analysis can open a non-invasive window onto pathological and metabolic processes in the body. Decades of clinical breath-gas analysis have revealed that changes in exhaled VOC concentrations are important rather than disease specific biomarkers. As physiological parameters, such as respiratory rate or cardiac output, have profound effects on exhaled VOCs, here we investigated VOC exhalation under respiratory manoeuvres. Breath VOCs were monitored by means of real-time mass-spectrometry during conventional FEV manoeuvres in 50 healthy humans. Simultaneously, we measured respiratory and hemodynamic parameters noninvasively. Tidal volume and minute ventilation increased by 292 and 171% during the manoeuvre. FEV manoeuvre induced substance specific changes in VOC concentrations. pET-CO2 and alveolar isoprene increased by 6 and 21% during maximum exhalation. Then they decreased by 18 and 37% at forced expiration mirroring cardiac output. Acetone concentrations rose by 4.5% despite increasing minute ventilation. Blood-borne furan and dimethyl-sulphide mimicked isoprene profile. Exogenous acetonitrile, sulphides, and most aliphatic and aromatic VOCs changed minimally. Reliable breath tests must avoid forced breathing. As isoprene exhalations mirrored FEV performances, endogenous VOCs might assure quality of lung function tests. Analysis of exhaled VOC concentrations can provide additional information on physiology of respiration and gas exchange.

  18. FEV manoeuvre induced changes in breath VOC compositions: an unconventional view on lung function tests.

    PubMed

    Sukul, Pritam; Schubert, Jochen K; Oertel, Peter; Kamysek, Svend; Taunk, Khushman; Trefz, Phillip; Miekisch, Wolfram

    2016-01-01

    Breath volatile organic compound (VOC) analysis can open a non-invasive window onto pathological and metabolic processes in the body. Decades of clinical breath-gas analysis have revealed that changes in exhaled VOC concentrations are important rather than disease specific biomarkers. As physiological parameters, such as respiratory rate or cardiac output, have profound effects on exhaled VOCs, here we investigated VOC exhalation under respiratory manoeuvres. Breath VOCs were monitored by means of real-time mass-spectrometry during conventional FEV manoeuvres in 50 healthy humans. Simultaneously, we measured respiratory and hemodynamic parameters noninvasively. Tidal volume and minute ventilation increased by 292 and 171% during the manoeuvre. FEV manoeuvre induced substance specific changes in VOC concentrations. pET-CO2 and alveolar isoprene increased by 6 and 21% during maximum exhalation. Then they decreased by 18 and 37% at forced expiration mirroring cardiac output. Acetone concentrations rose by 4.5% despite increasing minute ventilation. Blood-borne furan and dimethyl-sulphide mimicked isoprene profile. Exogenous acetonitrile, sulphides, and most aliphatic and aromatic VOCs changed minimally. Reliable breath tests must avoid forced breathing. As isoprene exhalations mirrored FEV performances, endogenous VOCs might assure quality of lung function tests. Analysis of exhaled VOC concentrations can provide additional information on physiology of respiration and gas exchange. PMID:27311826

  19. Variation in biogenic volatile organic compound emission pattern of Fagus sylvatica L. due to aphid infection

    NASA Astrophysics Data System (ADS)

    Joó, É.; Van Langenhove, H.; Šimpraga, M.; Steppe, K.; Amelynck, C.; Schoon, N.; Müller, J.-F.; Dewulf, J.

    2010-01-01

    Volatile organic compounds (VOCs) have been the focus of interest to understand atmospheric processes and their consequences in formation of ozone or aerosol particles; therefore, VOCs contribute to climate change. In this study, biogenic VOCs (BVOCs) emitted from Fagus sylvatica L. trees were measured in a dynamic enclosure system. In total 18 compounds were identified: 11 monoterpenes (MT), an oxygenated MT, a homoterpene (C 14H 18), 3 sesquiterpenes (SQT), isoprene and methyl salicylate. The frequency distribution of the compounds was tested to determine a relation with the presence of the aphid Phyllaphis fagi L. It was found that linalool, (E)-β-ocimene, α-farnesene and a homoterpene identified as (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), were present in significantly more samples when infection was present on the trees. The observed emission spectrum from F. sylvatica L. shifted from MT to linalool, α-farnesene, (E)-β-ocimene and DMNT due to the aphid infection. Sabinene was quantitatively the most prevalent compound in both, non-infected and infected samples. In the presence of aphids α-farnesene and linalool became the second and third most important BVOC emitted. According to our investigation, the emission fingerprint is expected to be more complex than commonly presumed.

  20. Determinants of personal, indoor and outdoor VOC concentrations: An analysis of the RIOPA data

    PubMed Central

    Su, Feng-Chiao; Mukherjee, Bhramar; Batterman, Stuart

    2014-01-01

    Community and environmental exposure to volatile organic compounds (VOCs) has been associated with a number of emission sources and activities, e.g., environmental tobacco smoke and pumping gasoline. Such factors have been identified from mostly small studies with relatively limited information regarding influences on VOC levels. This study uses data from the Relationship of Indoor Outdoor and Personal Air (RIOPA) study to investigate environmental, individual and social determinants of VOC concentrations. RIOPA included outdoor, indoor and personal measurements of 18 VOCs from 310 non-smoking households and adults in three cities and two seasons, and collected a wide range of information pertaining to participants, family members, households, and neighborhoods. Exposure determinants were identified using stepwise regressions and linear mixed-effect models. Most VOC exposure (66 to 78% of the total exposure, depending on VOC) occurred indoors, and outdoor VOC sources accounted for 5 (d-limonene) to 81% (carbon tetrachloride) of the total exposure. Personal exposure and indoor measurements had similar determinants, which depended on the VOC. Gasoline-related VOCs (e.g., benzene, methyl tertiary butyl ether) were associated with city, residences with attached garages, self-pumping of gas, wind speed, and house air exchange rate (AER). Odorant and cleaning-related VOCs (e.g., 1,4-dichlorobenzene and chloroform) also were associated with city and AER, and with house size and family members showering. Dry-cleaning and industry-related VOCs (e.g., tetrachloroethylene and trichloroethylene) were associated with city, residence water supply type, and dry-cleaner visits. These and other relationships were significant, explained from 10 to 40% of the variation, and are consistent with known emission sources and the literature. Outdoor concentrations had only two common determinants: city and wind speed. Overall, personal exposure was dominated by the home setting, although a

  1. The major volatile organic compound emitted from Arabidopsis thaliana flowers, the sesquiterpene (E)-β-caryophyllene, is a defense against a bacterial pathogen.

    PubMed

    Huang, Mengsu; Sanchez-Moreiras, Adela M; Abel, Christian; Sohrabi, Reza; Lee, Sungbeom; Gershenzon, Jonathan; Tholl, Dorothea

    2012-03-01

    Flowers have a high risk of pathogen attack because of their rich nutrient and moisture content, and high frequency of insect visitors. We investigated the role of (E)-β-caryophyllene in floral defense against a microbial pathogen. This sesquiterpene is a common volatile compound emitted from flowers, and is a major volatile released from the stigma of Arabidopsis thaliana flowers. Arabidopsis thaliana lines lacking a functional (E)-β-caryophyllene synthase or constitutively overexpressing this gene were challenged with Pseudomonas syringae pv. tomato DC3000, which is a bacterial pathogen of brassicaceous plants. Flowers of plant lines lacking (E)-β-caryophyllene emission showed greater bacterial growth on their stigmas than did wild-type flowers, and their seeds were lighter and misshapen. By contrast, plant lines with ectopic (E)-β-caryophyllene emission from vegetative parts were more resistant than wild-type plants to pathogen infection of leaves, and showed reduced cell damage and higher seed production. Based on in vitro experiments, (E)-β-caryophyllene seems to act by direct inhibition of bacterial growth, rather than by triggering defense signaling pathways. (E)-β-Caryophyllene thus appears to serve as a defense against pathogens that invade floral tissues and, like other floral volatiles, may play multiple roles in defense and pollinator attraction. PMID:22187939

  2. Enhanced optical power of GaN-based light-emitting diode with compound photonic crystals by multiple-exposure nanosphere-lens lithography

    SciTech Connect

    Zhang, Yonghui; Wei, Tongbo Xiong, Zhuo; Shang, Liang; Tian, Yingdong; Zhao, Yun; Zhou, Pengyu; Wang, Junxi; Li, Jinmin

    2014-07-07

    The light-emitting diodes (LEDs) with single, twin, triple, and quadruple photonic crystals (PCs) on p-GaN are fabricated by multiple-exposure nanosphere-lens lithography (MENLL) process utilizing the focusing behavior of polystyrene spheres. Such a technique is easy and economical for use in fabricating compound nano-patterns. The optimized tilted angle is decided to be 26.6° through mathematic calculation to try to avoid the overlay of patterns. The results of scanning electron microscopy and simulations reveal that the pattern produced by MENLL is a combination of multiple ovals. Compared to planar-LED, the light output power of LEDs with single, twin, triple, and quadruple PCs is increased by 14.78%, 36.03%, 53.68%, and 44.85% under a drive current 350 mA, respectively. Furthermore, all PC-structures result in no degradation of the electrical properties. The stimulated results indicate that the highest light extraction efficiency of LED with the clover-shape triple PC is due to the largest scattering effect on propagation of light from GaN into air.

  3. The effectiveness of circulating aeration in air and high purity oxygen systems for control of VOC emissions from aeration basins

    SciTech Connect

    Zhu, H.; Keener, T.C.; Bishop, P.L.; Orton, T.L.; Wang, M.; Siddiqui, K.F.

    1997-12-31

    A simple steady state circulating aeration system (CAS) model has been used to study the effects of volatility and degradability on the fate of VOCs in both air and high purity oxygen (HPO) systems. With increase of circulation ratio in an air CAS, air emissions by stripping can be significantly reduced for compounds of low degradabilities and high volatilities. Enhancement of biodegradation is more significant for compounds of high degradabilities and volatilities. A large portion of VOCs will remain in the wastewater when circulation ratio is high, especially for VOCs that are difficult to degrade. In HPO systems, emissions by stripping are much less than air systems. However, VOCs will remain in the wastewater if they have poor degradabilities. Volatilities of VOCs are not important in HPO systems. Due to their wide range and large uncertainties, degradation rate constants are a major factor determining the effectiveness of a CAS for VOC emission control

  4. Use of electronic nose and GC-MS in detection and monitoring some VOC

    NASA Astrophysics Data System (ADS)

    Delgado-Rodríguez, M.; Ruiz-Montoya, M.; Giraldez, I.; López, R.; Madejón, E.; Díaz, M. J.

    2012-05-01

    The aim of this study was to evaluate the use of an electronic nose (e-nose) as on-line, rapid method to quantify the MSW composting gases. Changes in selected VOCs (limonene, β-pinene, 2-butanone, undecane, toluene and dimethyl disulfide) during composting were studied and quantified by means of two different analytical methods (GC-MS and e-nose). The results of this study indicate that it is possible to differentiate and quantify the main gases emitted during Municipal Solid Waste- Legume Trimming Residues composting using an electronic nose equipped with 10 Metal Oxide Sensors. The electronic nose was able to detect a clear difference in volatile compounds profile of emitted gases in composting, using Principal Component Analysis (PCA) analysis. PCA successfully reduced the data sets from the sensors to two principal components, which accounted for 74.5%, 68.8% and 62.8% of the total variance by using patterns for initial, thermophilic and mesophilic composting phases respectively.

  5. Novel aqueous foams for suppressing VOC emission.

    PubMed

    Gautam, Pankaj S; Mohanty, Kishore K

    2004-05-01

    Reducing volatile organic compound (VOC) emissions from crude oil/gasoline distribution and storage facilities is important in controlling environmental pollution and enhancing workplace safety. Stable aqueous foam formulations are developed to provide a mass transfer barrier to the emission of VOCs during loading of gasoline. Experiments are carried out in a bench-scale foam cell using liquid hexane as oil. The foam columns of 32 cm in height were able to suppress the plateau concentration of hexane vapors in the effluent by 87% under experimental conditions tested. Vapor suppression increased with foam height but was almost insensitive to liquid viscosity. These experiments are then upscaled from bench-scale to a vessel having an exposed surface area of roughly 2 orders of magnitude higher. Gasoline is used as oil in the upscaled experiments, and the concentrations of volatile hydrocarbons in the effluent are measured during oil loading. A 40-cm-thick foam column is found to reduce the emissions by 96% for foams prepared with deionized water and by 93.8% for foams prepared with 3.5 wt % NaCl brine for 10 h of oil loading. PMID:15180071

  6. Odorous VOC emission following land application of swine manure slurry

    NASA Astrophysics Data System (ADS)

    Parker, David B.; Gilley, John; Woodbury, Bryan; Kim, Ki-Hyun; Galvin, Geordie; Bartelt-Hunt, Shannon L.; Li, Xu; Snow, Daniel D.

    2013-02-01

    Swine manure is often applied to crop land as a fertilizer source. Odor emissions from land-applied swine manure may pose a nuisance to downwind populations if manure is not applied with sufficient forethought. A research project was conducted to assess the time decay of odorous volatile organic compound (VOC) emissions following land application of swine manure. Three land application methods were compared: surface application, incorporation 24 h after surface application, and injection. Emission rates were measured in field plots using a small wind tunnel and sorbent tubes. VOCs including eight volatile fatty acids, five aromatics, and two sulfur-containing compounds were quantified by gas chromatography-mass spectrometry. In most cases, a first order exponential decay model adequately described the flux versus time relationship for the 24 h period following land application, but the model sometimes overestimated flux in the 6-24 h range. The same model but with the time term squared adequately predicted flux over the entire 24 h period. Three compounds (4-methylphenol, skatole, and 4-ethylphenol) accounted for 93 percent of the summed odor activity value. First order decay constants (k) for these three compounds ranged from 0.157 to 0.996 h-1. When compared to surface application, injection of swine manure resulted in 80-95 percent lower flux for the most odorous aromatic compounds. These results show that VOC flux decreases rapidly following land application of swine manure, declining below levels of detection and near background levels after 4 to 8 h.

  7. Observations of Vertical Gradients in Composition, Oxidation States, and Diurnal Dynamics for a Comprehensive Suite of VOCs from 10 to 525 m in the San Joaquin Valley, California

    NASA Astrophysics Data System (ADS)

    Misztal, P. K.; Weber, R.; Guha, A.; Seco, R.; Kim, S.; Guenther, A. B.; Goldstein, A. H.

    2015-12-01

    Volatile organic compounds (VOCs) are emitted by numerous anthropogenic and biogenic sources and undergo oxidative processing, as well as horizontal and vertical transport, in the troposphere. Understanding the dynamics of chemical and physical land atmosphere exchange processes and their impacts on atmospheric chemistry requires high temporal resolution of observations at multiple heights and the knowledge of the sources and sinks. We measured dynamic composition changes of VOCs as a function of height (5 inlets from 10 to 525 m, switching every 2 minutes, full profile every 10 minutes) for more than a year using a PTR-QMS. Here, we focus on a multi-week period in February 2013 when simultaneous SRI-TOFMS and PTR-QMS took place. More than 300 ions were detected within an m/z range of 0.000 - 400.000 Th and 260 ions were analyzed. Chemical formulas were assigned to more than 50% of these ions. Late winter is a period when anthropogenic influences are relatively high including remote sources in the Central Valley. Biogenic influences are low at this time of year, but were clearly observed. The average diurnal vertical gradients (Figure 1) showed trends and patterns and behavior consistent with boundary layer dynamics, wind profiles and source activity for a broad array of VOCs and source categories. Mass concentration of oxygenated VOCs with 2, 3 or more oxygens or with nitrogen+oxygen had an increasing tendency with height. The opposite was true for pure hydrocarbons and reduced nitrogen containing VOCs which generally decrease with height. The remaining species comprised halogenated as well as other volatile products. Average oxidation state ranged from -2.0 to 4.3. These observations are useful to reflect the dynamics of VOCs at a rural site in the Central Valley and could be particularly useful for comparison with models of atmospheric chemistry that include PBL dynamics. Figure 1: Gradient concentration diurnal profiles for 48 selected ions, showing the

  8. GROUND WATER SAMPLING FOR VOCS

    EPA Science Inventory

    Sampling protocol should be dictated by the sampling objective(s). It is important to obtain representative ground water samples, regardless of the sampling objective(s). Low-flow (minimum draw-down) purging and sampling techniques are best in most instances, particularly for VOC...

  9. [Emission Characteristics of VOCs from Typical Restaurants in Beijing].

    PubMed

    Cui, Tong; Cheng, Jing-chen; He, Wan-qing; Ren, Pei-fang; Nie, Lei; Xu, Dong-yao; Pan, Tao

    2015-05-01

    Using the EPA method, emission of volatile organic compounds (VOCs) , sampled from barbecue, Chinese and Western fast-food, Sichuan cuisine and Zhejiang cuisine restaurants in Beijing was investigated. VOCs concentrations and components from different cuisines were studied. The results indicated that based on the calibrated baseline ventilation volume, the VOCs emission level from barbecue was the highest, reaching 12.22 mg · m(-3), while those from fast-food of either Chinese or Western, Sichuan cuisine and Zhejiang cuisine were about 4 mg · m(-3). The components of VOCs from barbecue were different from those in the other cuisines, which were mainly propylene, 1-butene, n-butane, etc. The non-barbecue cuisines consisted of high concentration of alcohols, and Western fast-food contained relatively high proportion of aldehydes and ketones organic compounds. According to emission concentration of baseline ventilation volume, barbecue released more pollutants than the non-barbecue cuisines at the same scale. So, barbecue should be supervised and controlled with the top priority. PMID:26314095

  10. [Study of VOCs emission prediction and control based on dynamic CGE].

    PubMed

    Liu, Chang-Xin; Wang, Yu-Fei; Hao, Zheng-Ping; Wang, Zheng

    2013-12-01

    Researches on controlling volatile organic compounds (VOCs) through macroeconomic policy from the view of cost-benefit analysis are very important for our country to improve the air environment. Based on our previous study, this paper predicted future VOCs emissions until 2020 under current policies with 2007 as reference year by using dynamic CGE model. Meanwhile, environmental tax was imposed in ten industries with high emission and the impacts of emissions and economic system were discussed. Finally, policy implementations for VOCs emission control were suggested for policy-makers. The results showed that environment tax could mitigate VOCs emission, but it also resulted in high cost. Owing to the highly related relationship between different sectors, although transport sector was not taxed, it also suffered a great economic influence. Thus, when using the tax policy for reducing VOCs, subsidy for special sector is necessary. PMID:24640924

  11. Measuring concentrations of volatile organic compounds in vinyl flooring.

    PubMed

    Cox, S S; Little, J C; Hodgson, A T

    2001-08-01

    The initial solid-phase concentration of volatile organic compounds (VOCs) is a key parameter influencing the emission characteristics of many indoor materials. Solid-phase measurements are typically made using solvent extraction or thermal headspace analysis. The high temperatures and chemical solvents associated with these methods can modify the physical structure of polymeric materials and, consequently, affect mass transfer characteristics. To measure solid-phase concentrations under conditions resembling those in which the material would be installed in an indoor environment, a new technique was developed for measuring VOC concentrations in vinyl flooring (VF) and similar materials. A 0.09-m2 section of new VF was punched randomly to produce -200 0.78-cm2 disks. The disks were milled to a powder at -140 degrees C to simultaneously homogenize the material and reduce the diffusion path length without loss of VOCs. VOCs were extracted from the VF particles at room temperature by fluidized-bed desorption (FBD) and by direct thermal desorption (DTD) at elevated temperatures. The VOCs in the extraction gas from FBD and DTD were collected on sorbent tubes and analyzed by gas chromatography/mass spectrometry (GC/MS). Seven VOCs emitted by VF were quantified. Concentration measurements by FBD ranged from 5.1 microg/g VF for n-hexadecane to 130 microg/g VF for phenol. Concentrations measured by DTD were higher than concentrations measured by FBD. Differences between FBD and DTD results may be explained using free-volume and dual-mobility sorption theory, but further research is necessary to more completely characterize the complex nature of a diffusant in a polymer matrix. PMID:11518293

  12. Modelling Contribution of Biogenic VOCs to New Particle Formation in the Jülich Plant Atmosphere Chamber

    NASA Astrophysics Data System (ADS)

    Liao, L.; Boy, M.; Mogensen, D.; Mentel, T. F.; Kleist, E.; Kiendler-Scharr, A.; Tillman, R.; Kulmala, M. T.; Dal Maso, M.

    2012-12-01

    Biogenic VOCs are substantially emitted from vegetation to atmosphere. The oxidation of BVOCs by OH, O3, and NO3 in air generating less volatile compounds may lead to the formation and growth of secondary organic aerosol, and thus presents a link to the vegetation, aerosol, and climate interaction system (Kulmala et al, 2004). Studies including field observations, laboratory experiments and modelling have improved our understanding on the connection between BVOCs and new particle formation mechanism in some extent (see e.g. Tunved et al., 2006; Mentel et al., 2009). Nevertheless, the exact formation process still remains uncertain, especially from the perspective of BVOC contributions. The purpose of this work is using the MALTE aerosol dynamics and air chemistry box model to investigate aerosol formation from reactions of direct tree emitted VOCs in the presence of ozone, UV light and artificial solar light in an atmospheric simulation chamber. This model employs up to date air chemical reactions, especially the VOC chemistry, which may potentially allow us to estimate the contribution of BVOCs to secondary aerosol formation, and further to quantify the influence of terpenes to the formation rate of new particles. Experiments were conducted in the plant chamber facility at Forschungszentrum Jülich, Germany (Jülich Plant Aerosol Atmosphere Chamber, JPAC). The detail regarding to the chamber facility has been written elsewhere (Mentel et al., 2009). During the experiments, sulphuric acid was measured by CIMS. VOC mixing ratios were measured by two GC-MS systems and PTR-MS. An Airmodus Particle size magnifier coupled with a TSI CPC and a PH-CPC were used to count the total particle number concentrations with a detection limit close to the expected size of formation of fresh nanoCN. A SMPS measured the particle size distribution. Several other parameters including ozone, CO2, NO, Temperature, RH, and flow rates were also measured. MALTE is a modular model to predict

  13. Relationship between air exchange rate and indoor VOC levels

    SciTech Connect

    Otson, R.; Williams, D.T.; Fellin, P.

    1998-12-31

    It is often assumed that the air quality is better in leaky than in airtight buildings. To test this anecdotal hypothesis, data from two Canadian surveys were examined. Indoor measurements of 28 volatile organic compounds (VOCs) were made by means of a passive sampling method during the 24 to 48 h study periods in both studies, and air exchange rates were determined by the perfluorocarbon tracer approach. The air exchange rates ranged between about 0.1 to 2.5 air changes per hour in 54 test homes in the Greater Toronto Area (GTA). Other information on building age and construction, renovation activities and occupant activities that potentially influenced indoor VOC concentrations in the homes was collected by means of a questionnaire. The statistical relationships between the concentrations of VOCs and air exchange were determined. Correlation coefficients between the airborne concentrations of each VOC and the air exchange rates for the homes were all < 0.1 indicating that the relationship between the air exchange and indoor VOC concentrations is tenuous. Since the questionnaire responses did not provide quantitative estimates of indoor emissions, a quantitative correlation between responses and indoor concentrations could not be established nor was a consistent pattern evident between these responses and the occurrence of high indoor concentrations. The lack of definitive quantitative relationships is not surprising considering the complexity of indoor environments, the lack of a detailed inventory of indoor sources and their emission rates and a lack of information or understanding of indoor sinks. The findings, on the effect of air exchange rates and the value of questionnaires in studies on indoor VOCs are consistent with findings in other similar studies.

  14. Investigation of VOCs associated with different characteristics of breast cancer cells

    PubMed Central

    Lavra, Luca; Catini, Alexandro; Ulivieri, Alessandra; Capuano, Rosamaria; Baghernajad Salehi, Leila; Sciacchitano, Salvatore; Bartolazzi, Armando; Nardis, Sara; Paolesse, Roberto; Martinelli, Eugenio; Di Natale, Corrado

    2015-01-01

    The efficacy of breath volatile organic compounds (VOCs) analysis for the screening of patients bearing breast cancer lesions has been demonstrated by using gas chromatography and artificial olfactory systems. On the other hand, in-vitro studies suggest that VOCs detection could also give important indications regarding molecular and tumorigenic characteristics of tumor cells. Aim of this study was to analyze VOCs in the headspace of breast cancer cell lines in order to ascertain the potentiality of VOCs signatures in giving information about these cells and set-up a new sensor system able to detect breast tumor-associated VOCs. We identified by Gas Chromatography-Mass Spectrometry analysis a VOCs signature that discriminates breast cancer cells for: i) transformed condition; ii) cell doubling time (CDT); iii) Estrogen and Progesterone Receptors (ER, PgR) expression, and HER2 overexpression. Moreover, the signals obtained from a temperature modulated metal oxide semiconductor gas sensor can be classified in order to recognize VOCs signatures associated with breast cancer cells, CDT and ER expression. Our results demonstrate that VOCs analysis could give clinically relevant information about proliferative and molecular features of breast cancer cells and pose the basis for the optimization of a low-cost diagnostic device to be used for tumors characterization. PMID:26304457

  15. What effect does VOC sampling time have on derived OH reactivity?

    NASA Astrophysics Data System (ADS)

    Sonderfeld, Hannah; White, Iain R.; Goodall, Iain C. A.; Hopkins, James R