WorldWideScience

Sample records for total pah emission

  1. PAH emissions from coal combustion and waste incineration.

    Science.gov (United States)

    Hsu, Wei Ting; Liu, Mei Chen; Hung, Pao Chen; Chang, Shu Hao; Chang, Moo Been

    2016-11-15

    The characteristics of PAHs that are emitted by a municipal waste incinerator (MWI) and coal-fired power plant are examined via intensive sampling. Results of flue gas sampling reveal the potential for PAH formation within the selective catalytic reduction (SCR) system of a coal-fired power plant. In the large-scale MWI, the removal efficiency of PAHs achieved with the pilot-scaled catalytic filter (CF) exceeds that achieved by activated carbon injection with a bag filter (ACI+BF) owing to the effective destruction of gas-phase contaminants by a catalyst. A significantly lower PAH concentration (1640ng/g) was measured in fly ash from a CF module than from an ACI+BF system (5650ng/g). Replacing the ACI+BF system with CF technology would significantly reduce the discharge factor (including emission and fly ash) of PAHs from 251.6 to 77.8mg/ton-waste. The emission factors of PAHs that are obtained using ACI+BF and the CF system in the MWI are 8.05 and 7.13mg/ton, respectively. However, the emission factor of MWI is significantly higher than that of coal-fired power plant (1.56mg/ton). From the perspective of total environmental management to reduce PAH emissions, replacing the original ACI+BF process with a CF system is expected to reduce environmental impact thereof. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Mitigation of PAH and nitro-PAH emissions from nonroad diesel engines.

    Science.gov (United States)

    Liu, Z Gerald; Wall, John C; Ottinger, Nathan A; McGuffin, Dana

    2015-03-17

    More stringent emission requirements for nonroad diesel engines introduced with U.S. Tier 4 Final and Euro Stage IV and V regulations have spurred the development of exhaust aftertreatment technologies. In this study, several aftertreatment configurations consisting of diesel oxidation catalysts (DOC), diesel particulate filters (DPF), Cu zeolite-, and vanadium-based selective catalytic reduction (SCR) catalysts, and ammonia oxidation (AMOX) catalysts are evaluated using both Nonroad Transient (NRTC) and Steady (8-mode NRSC) Cycles in order to understand both component and system-level effects of diesel aftertreatment on emissions of polycyclic aromatic hydrocarbons (PAH) and their nitrated derivatives (nitro-PAH). Emissions are reported for four configurations including engine-out, DOC+CuZ-SCR+AMOX, V-SCR+AMOX, and DOC+DPF+CuZ-SCR+AMOX. Mechanisms responsible for the reduction, and, in some cases, the formation of PAH and nitro-PAH compounds are discussed in detail, and suggestions are provided to minimize the formation of nitro-PAH compounds through aftertreatment design optimizations. Potency equivalency factors (PEFs) developed by the California Environmental Protection Agency are then applied to determine the impact of aftertreatment on PAH-derived exhaust toxicity. Finally, a comprehensive set of exhaust emissions including criteria pollutants, NO2, total hydrocarbons (THC), n-alkanes, branched alkanes, saturated cycloalkanes, aromatics, aldehydes, hopanes and steranes, and metals is provided, and the overall efficacy of the aftertreatment configurations is described. This detailed summary of emissions from a current nonroad diesel engine equipped with advanced aftertreatment can be used to more accurately model the impact of anthropogenic emissions on the atmosphere.

  3. Influence of PAHs among other coastal environmental variables on total and PAH-degrading bacterial communities.

    Science.gov (United States)

    Sauret, Caroline; Tedetti, Marc; Guigue, Catherine; Dumas, Chloé; Lami, Raphaël; Pujo-Pay, Mireille; Conan, Pascal; Goutx, Madeleine; Ghiglione, Jean-François

    2016-03-01

    We evaluated the relative impact of anthropogenic polycyclic aromatic hydrocarbons (PAHs) among biogeochemical variables on total, metabolically active, and PAH bacterial communities in summer and winter in surface microlayer (SML) and subsurface seawaters (SSW) across short transects along the NW Mediterranean coast from three harbors, one wastewater effluent, and one nearshore observatory reference site. At both seasons, significant correlations were found between dissolved total PAH concentrations and PAH-degrading bacteria that formed a gradient from the shore to nearshore waters. Accumulation of PAH degraders was particularly high in the SML, where PAHs accumulated. Harbors and wastewater outfalls influenced drastically and in a different way the total and active bacterial community structure, but they only impacted the communities from the nearshore zone (PAH concentrations on the spatial and temporal dynamic of total and active communities in this area, but this effect was putted in perspective by the importance of other biogeochemical variables.

  4. PAH EMISSION AT THE BRIGHT LOCATIONS OF PDRs: THE grandPAH HYPOTHESIS

    International Nuclear Information System (INIS)

    Andrews, H.; Tielens, A. G. G. M.; Boersma, C.; Allamandola, L. J.; Werner, M. W.; Livingston, J.

    2015-01-01

    The polycyclic aromatic hydrocarbon (PAH) emission observed in the Spitzer Infrared Spectrograph spectra of bright mid-IR locations of NGC 7023, NGC 2023, and NGC 1333 was analyzed. These objects show large variations in PAH band ratios when studied through spectral mapping. Nevertheless, the mid-IR spectra at these bright spots show a remarkably similar PAH emission. We used the NASA Ames PAH IR Spectroscopic Database to fit the observations and analyze the derived PAH populations. Our results show that PAH emission in the 5–15 μm range appears to be rather insensitive to variations of the radiation field. Similar PAH populations of neutral small to medium-sized PAHs (∼50%), with ionized species contributing in slightly less than 50%, provide very good fits. Analyzing the degeneracy of the results shows that subtle (but intrinsic) variations in the emission properties of individual PAHs lead to observable differences in the resulting spectra. On top of this, we found that variations of <30% in the PAH abundances would lead to noticeable spectral differences between the three photodissociation regions (PDRs). Therefore, PAH populations must be remarkably similar at these different lines of sight. To account for this, we suggest the concept of grandPAHs as a unique mixture of the most stable PAHs emitting at these spots. Using NGC 7023 as an example, the grandPAHs refer to the robust PAH population that results from the intense processing of PAHs at the border limit between the PDR and the molecular cloud, where, due to the UV radiation that destroys the PAH population, the abundance of PAHs starts decreasing as we move toward the star

  5. PAH EMISSION AT THE BRIGHT LOCATIONS OF PDRs: THE grandPAH HYPOTHESIS

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, H.; Tielens, A. G. G. M. [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands); Boersma, C.; Allamandola, L. J. [NASA Ames Research Center, MS 245-6, Moffett Field, CA 94035 (United States); Werner, M. W.; Livingston, J., E-mail: heandrew@strw.leidenuniv.nl, E-mail: Christiaan.Boersma@nasa.gov [Jet Propulsion Laboratory, MC 264-767, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)

    2015-07-01

    The polycyclic aromatic hydrocarbon (PAH) emission observed in the Spitzer Infrared Spectrograph spectra of bright mid-IR locations of NGC 7023, NGC 2023, and NGC 1333 was analyzed. These objects show large variations in PAH band ratios when studied through spectral mapping. Nevertheless, the mid-IR spectra at these bright spots show a remarkably similar PAH emission. We used the NASA Ames PAH IR Spectroscopic Database to fit the observations and analyze the derived PAH populations. Our results show that PAH emission in the 5–15 μm range appears to be rather insensitive to variations of the radiation field. Similar PAH populations of neutral small to medium-sized PAHs (∼50%), with ionized species contributing in slightly less than 50%, provide very good fits. Analyzing the degeneracy of the results shows that subtle (but intrinsic) variations in the emission properties of individual PAHs lead to observable differences in the resulting spectra. On top of this, we found that variations of <30% in the PAH abundances would lead to noticeable spectral differences between the three photodissociation regions (PDRs). Therefore, PAH populations must be remarkably similar at these different lines of sight. To account for this, we suggest the concept of grandPAHs as a unique mixture of the most stable PAHs emitting at these spots. Using NGC 7023 as an example, the grandPAHs refer to the robust PAH population that results from the intense processing of PAHs at the border limit between the PDR and the molecular cloud, where, due to the UV radiation that destroys the PAH population, the abundance of PAHs starts decreasing as we move toward the star.

  6. Global time trends in PAH emissions from motor vehicles

    Science.gov (United States)

    Shen, Huizhong; Tao, Shu; Wang, Rong; Wang, Bin; Shen, Guofeng; Li, Wei; Su, Shenshen; Huang, Ye; Wang, Xilong; Liu, Wenxin; Li, Bengang; Sun, Kang

    2011-04-01

    Emission from motor vehicles is the most important source of polycyclic aromatic hydrocarbons (PAHs) in urban areas. Emission factors of individual PAHs for motor vehicles reported in the literature varied 4 to 5 orders of magnitude, leading to high uncertainty in emission inventory. In this study, key factors affecting emission factors of PAHs (EF PAH) for motor vehicles were evaluated quantitatively based on thousands of EF PAH measured in 16 countries for over 50 years. The result was used to develop a global emission inventory of PAHs from motor vehicles. It was found that country and vehicle model year are the most important factors affecting EF PAH, which can be quantified using a monovariate regression model with per capita gross domestic production (purchasing power parity) as a sole independent variable. On average, 29% of variation in log-transformed EF PAH could be explained by the model, which was equivalent to 90% reduction in overall uncertainty on arithmetic scale. The model was used to predict EF PAH and subsequently PAH emissions from motor vehicles for various countries in the world during a period from 1971 to 2030. It was estimated that the global emission reached its peak value of approximate 101 Gg in 1978 and decreased afterwards due to emission control in developed countries. The annual emission picked up again since 1990 owing to accelerated energy consumption in China and other developing countries. With more and more rigid control measures taken in the developing world, global emission of PAHs is currently passing its second peak. It was predicted that the emission would decrease from 77 Gg in 2010 to 42 Gg in 2030.

  7. PAH emissions from old and new types of domestic hot water boilers.

    Science.gov (United States)

    Horak, Jiri; Kubonova, Lenka; Krpec, Kamil; Hopan, Frantisek; Kubesa, Petr; Motyka, Oldrich; Laciok, Vendula; Dej, Milan; Ochodek, Tadeas; Placha, Daniela

    2017-06-01

    Five different domestic heating boilers (automatic, over-fire, with down-draft combustion and gasification) and three types of fuel (lignite, wood and mixed fuel) were examined in 25 combustion tests and correlated with the emissions of particulate matter (PM), carbon monoxide (CO), total organic carbon (TOC) and 12 polycyclic aromatic hydrocarbons (PAHs with MW = 178-278 g/mol) focusing on particle phase. However, the distribution of 12 PAHs in gas phase was considered as well due to the presence mainly of lighter PAHs in gas phase. The PAHs, as well as the CO and TOC, are the indicators of incomplete combustion, and in this study PAH emission increased significantly with increasing emissions of CO and TOC. The PAHs were mainly detected on PM 2.5 , their contents were increasing linearly with increasing PM 2.5 emissions. The highest emission factors of PAHs were measured for boilers of old construction, such as over-fire boiler (5.8-929 mg/kg) and boiler with down-draft combustion (3.1-54.1 mg/kg). Modern types of boilers produced much lower emissions of PAHs, in particular, automatic boiler (0.3-3.3 mg/kg) and gasification boilers (0.2-6.7 mg/kg). In general, the inefficient combustion at reduced output of boilers generated 1.4-17.7 times more emissions of PAHs than the combustion at nominal output of boilers. It is recommended to operate boilers at nominal output with sufficient air supply and to use the proper fuel to minimise PAHs emissions from domestic heating appliances. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. The PAH Emission Characteristics of the Reflection Nebula NGC 2023

    International Nuclear Information System (INIS)

    Peeters, Els; Bauschlicher, Charles W. Jr.; Allamandola, Louis J.; Tielens, Alexander G. G. M.; Ricca, Alessandra; Wolfire, Mark G.

    2017-01-01

    We present 5–20 μ m spectral maps of the reflection nebula NGC 2023 obtained with the Infrared Spectrograph SL and SH modes on board the Spitzer Space Telescope, which reveal emission from polycyclic aromatic hydrocarbons (PAHs), C 60 , and H 2 superposed on a dust continuum. We show that several PAH emission bands correlate with each other and exhibit distinct spatial distributions that reveal a spatial sequence with distance from the illuminating star. We explore the distinct morphology of the 6.2, 7.7, and 8.6 μ m PAH bands and find that at least two spatially distinct components contribute to the 7–9 μ m PAH emission in NGC 2023. We report that the PAH features behave independently of the underlying plateaus. We present spectra of compact, oval PAHs ranging in size from C 66 to C 210 , determined computationally using density functional theory, and we investigate trends in the band positions and relative intensities as a function of PAH size, charge, and geometry. Based on the NASA Ames PAH database, we discuss the 7–9 μ m components in terms of band assignments and relative intensities. We assign the plateau emission to very small grains with possible contributions from PAH clusters and identify components in the 7–9 μ m emission that likely originate in these structures. Based on the assignments and the observed spatial sequence, we discuss the photochemical evolution of the interstellar PAH family as the PAHs are more and more exposed to the radiation field of the central star in the evaporative flows associated with the Photo-Dissociation Regions in NGC 2023.

  9. The PAH Emission Characteristics of the Reflection Nebula NGC 2023

    Energy Technology Data Exchange (ETDEWEB)

    Peeters, Els [Department of Physics and Astronomy, University of Western Ontario, London, ON N6A 3K7 (Canada); Bauschlicher, Charles W. Jr. [Entry Systems and Technology Division, Mail Stop 230-3, NASA Ames Research Center, Moffett Field, CA 94035 (United States); Allamandola, Louis J. [NASA Ames Research Center, Space Science Division, Mail Stop 245-6, Moffett Field, CA 94035 (United States); Tielens, Alexander G. G. M. [Leiden Observatory, P.O. Box 9513, 2300 RA Leiden (Netherlands); Ricca, Alessandra [Carl Sagan Center, SETI Institute, 189 N. Bernardo Avenue, Suite 100, Mountain View, CA 94043 (United States); Wolfire, Mark G., E-mail: epeeters@uwo.ca [Astronomy Department, University of Maryland, College Park, MD 20742 (United States)

    2017-02-20

    We present 5–20 μ m spectral maps of the reflection nebula NGC 2023 obtained with the Infrared Spectrograph SL and SH modes on board the Spitzer Space Telescope, which reveal emission from polycyclic aromatic hydrocarbons (PAHs), C{sub 60}, and H{sub 2} superposed on a dust continuum. We show that several PAH emission bands correlate with each other and exhibit distinct spatial distributions that reveal a spatial sequence with distance from the illuminating star. We explore the distinct morphology of the 6.2, 7.7, and 8.6 μ m PAH bands and find that at least two spatially distinct components contribute to the 7–9 μ m PAH emission in NGC 2023. We report that the PAH features behave independently of the underlying plateaus. We present spectra of compact, oval PAHs ranging in size from C{sub 66} to C{sub 210}, determined computationally using density functional theory, and we investigate trends in the band positions and relative intensities as a function of PAH size, charge, and geometry. Based on the NASA Ames PAH database, we discuss the 7–9 μ m components in terms of band assignments and relative intensities. We assign the plateau emission to very small grains with possible contributions from PAH clusters and identify components in the 7–9 μ m emission that likely originate in these structures. Based on the assignments and the observed spatial sequence, we discuss the photochemical evolution of the interstellar PAH family as the PAHs are more and more exposed to the radiation field of the central star in the evaporative flows associated with the Photo-Dissociation Regions in NGC 2023.

  10. Effects of low concentration biodiesel blends application on modern passenger cars. Part 3: Impact on PAH, nitro-PAH, and oxy-PAH emissions

    International Nuclear Information System (INIS)

    Karavalakis, Georgios; Fontaras, Georgios; Ampatzoglou, Dimitrios; Kousoulidou, Marina; Stournas, Stamoulis; Samaras, Zissis; Bakeas, Evangelos

    2010-01-01

    This study explores the impact of five different types of methyl esters on polycyclic aromatic hydrocarbon (PAH), nitrated-PAH and oxygenated PAH emissions. The measurements were conducted on a chassis dynamometer, according to the European regulation. Each of the five different biodiesels was blended with EN590 diesel at a proportion of 10-90% v/v (10% biodiesel concentration). The vehicle was a Euro 3 compliant common-rail diesel passenger car. Emission measurements were performed over the NEDC and compared with those of the real traffic-based Artemis driving cycles. The experimental results showed that the addition of biodiesel led to some important increases in low molecular-weight PAHs (phenanthrene and anthracene) and to both increases and reductions in large PAHs which are characterised by their carcinogenic and mutagenic properties. Nitro-PAHs were found to reduce with biodiesel whereas oxy-PAH emissions presented important increases with the biodiesel blends. The impact of biodiesel source material was particularly clear on the formation of PAH compounds. It was found that most PAH emissions decreased as the average load and speed of the driving cycle increased. Cold-start conditions negatively influenced the formation of most PAH compounds. A similar trend was observed with particulate alkane emissions. - This investigation is a contribution to the understanding the impact of different biodiesels on the formation of PAHs, nitro-PAHs and oxy-PAHs over different driving conditions.

  11. Mosses as an integrating tool for monitoring PAH atmospheric deposition: comparison with total deposition and evaluation of bioconcentration factors. A year-long case-study.

    Science.gov (United States)

    Foan, Louise; Domercq, Maria; Bermejo, Raúl; Santamaría, Jesús Miguel; Simon, Valérie

    2015-01-01

    Polycyclic aromatic hydrocarbon (PAH) atmospheric deposition was evaluated at a remote site in Northern Spain using moss biomonitoring with Hylocomium splendens (Hedw.) Schimp., and by measuring the total deposition fluxes of PAHs. The year-long study allowed seasonal variations of PAH content in mosses to be observed, and these followed a similar trend to those of PAH fluxes in total deposition. Generally, atmospheric deposition of PAHs is greater in winter than in summer, due to more PAH emissions from domestic heating, less photoreactivity of the compounds, and intense leaching of the atmosphere by wet deposition. However, fractionation of these molecules between the environmental compartments occurs: PAH fluxes in total deposition and PAH concentrations in mosses are correlated with their solubility (r=0.852, pPAH fluxes can be estimated with moss biomonitoring data if the bioconcentration or 'enriching' factors are known. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. PAH diagnostic ratios for the identification of pollution emission sources

    International Nuclear Information System (INIS)

    Tobiszewski, Marek; Namieśnik, Jacek

    2012-01-01

    Polycyclic aromatic hydrocarbon (PAH) diagnostic ratios have recently come into common use as a tool for identifying and assessing pollution emission sources. Some diagnostic ratios are based on parent PAHs, others on the proportions of alkyl-substituted to non-substituted molecules. The ratios are applicable to PAHs determined in different environmental media: air (gas + particle phase), water, sediment, soil, as well as biomonitor organisms such as leaves or coniferous needles, and mussels. These ratios distinguish PAH pollution originating from petroleum products, petroleum combustion and biomass or coal burning. The compounds involved in each ratio have the same molar mass, so it is assumed they have similar physicochemical properties. Numerous studies show that diagnostic ratios change in value to different extents during phase transfers and environmental degradation. The paper reviews applications of diagnostic ratios, comments on their use and specifies their limitations. - Highlights: ► PAH diagnostic ratios may identify pollution coming from petroleum spills, fuel combustion and coal or biomass burning. ► They are sensitive to changes during PAHs environmental fate processes. ► Some diagnostic ratios are of limited value due to fast photodegradation of one of the compounds. - The paper reviews PAH diagnostic ratios that are applied to identify pollution emission originating from petroleum products, fuel combustion or coal and biomass burning.

  13. Enhanced PM10 bounded PAHs from shipping emissions

    Science.gov (United States)

    Pongpiachan, S.; Hattayanone, M.; Choochuay, C.; Mekmok, R.; Wuttijak, N.; Ketratanakul, A.

    2015-05-01

    Earlier studies have highlighted the importance of maritime transport as a main contributor of air pollutants in port area. The authors intended to investigate the effects of shipping emissions on the enhancement of PM10 bounded polycyclic aromatic hydrocarbons (PAHs) and mutagenic substances in an industrial area of Rayong province, Thailand. Daily PM10 speciation data across two air quality observatory sites in Thailand during 2010-2013 were collected. Diagnostic binary ratios of PAH congeners, analysis of variances (ANOVA), and principal component analysis (PCA) were employed to evaluate the enhanced genotoxicity of PM10 during the docking period. Significant increase of PAHs and mutagenic index (MI) of PM10 were observed during the docking period in both sampling sites. Although stationary sources like coal combustions from power plants and vehicular exhausts from motorway can play a great role in enhancing PAH concentrations, regulating shipping emissions from diesel engine in the port area like Rayong is predominantly crucial.

  14. PM, carbon, and PAH emissions from a diesel generator fuelled with soy-biodiesel blends

    International Nuclear Information System (INIS)

    Tsai, Jen-Hsiung; Chen, Shui-Jen; Huang, Kuo-Lin; Lin, Yuan-Chung; Lee, Wen-Jhy; Lin, Chih-Chung; Lin, Wen-Yinn

    2010-01-01

    Biodiesels have received increasing attention as alternative fuels for diesel engines and generators. This study investigates the emissions of particulate matter (PM), total carbon (TC), e.g., organic/elemental carbons, and polycyclic aromatic hydrocarbons (PAHs) from a diesel generator fuelled with soy-biodiesel blends. Among the tested diesel blends (B0, B10 (10 vol% soy-biodiesel), B20, and B50), B20 exhibited the lowest PM emission concentration despite the loads (except the 5 kW case), whereas B10 displayed lower PM emission factors when operating at 0 and 10 kW than the other fuel blends. The emission concentrations or factors of EC, OC, and TC were the lowest when B10 or B20 was used regardless of the loading. Under all tested loads, the average concentrations of total-PAHs emitted from the generator using the B10 and B20 were lower (by 38% and 28%, respectively) than those using pure petroleum diesel fuel (B0), while the emission factors of total-PAHs decreased with an increasing ratio of biodiesel to premium diesel. With an increasing loading, although the brake specific fuel consumption decreased, the energy efficiency increased despite the bio/petroleum diesel ratio. Therefore, soy-biodiesel is promising for use as an alternative fuel for diesel generators to increase energy efficiency and reduce the PM, carbon, and PAH emissions.

  15. ON THE VIABILITY OF THE PAH MODEL AS AN EXPLANATION OF THE UNIDENTIFIED INFRARED EMISSION FEATURES

    International Nuclear Information System (INIS)

    Zhang, Yong; Kwok, Sun

    2015-01-01

    Polycyclic aromatic hydrocarbon (PAH) molecules are widely considered the preferred candidate for the carrier of the unidentified infrared emission bands observed in the interstellar medium and circumstellar envelopes. In this paper, we report the results of fitting a variety of non-PAH spectra (silicates, hydrogenated amorphous carbon, coal, and even artificial spectra) using the theoretical infrared spectra of PAHs from the NASA Ames PAH IR Spectroscopic Database. We show that these non-PAH spectra can be well fitted by PAH mixtures. This suggests that a general match between astronomical spectra and those of PAH mixtures does not necessarily provide definitive support for the PAH hypothesis

  16. An experimental investigation of PAH emissions from a heavy duty diesel engine fuelled with biodiesel and its blend

    International Nuclear Information System (INIS)

    Shah, A. N.; Shan, G.E.Y.; Wei, T.J.; Hua, L.Z.

    2008-01-01

    For the comparison of emission of polycyclic aromatic hydrocarbons (PAHs) from diesel biodiesel and its 20% blend with diesel, and their carcinogenic potencies, an experimental study has been conducted on a turbocharged, intercooled and direct injection diesel engine. Total PAHs (solid and gas) from diesel, B20 and B100 at low load were more than those at high loads. Total PAH emissions from the test fuels at the rated speed were more than those at maximum torque speed. Benzo[a] pyrene (BaP) brake specific emission of biodiesel is less than that of diesel. LMW-PAH emissions for the test fuels are all higher than those of MMW and HMW PAH. Biodiesel and B20 reduce both the total Benzo[a] pyrene equivalent concentration (BaP/sub eq/) and the total mean-PAHs as compared to commercial diesel fuel. BSFC of the engine increased but its brake power decreased in the cases of B20 and biodiesel. (author)

  17. Carbonyl compounds and PAH emissions from CNG heavy-duty engine

    International Nuclear Information System (INIS)

    Gambino, M.; Cericola, R.; Corbo, P.; Iannaccone, S.

    1993-01-01

    Previous works carried out in Istituto Motori laboratories have shown that natural gas is a suitable fuel for general means of transportation. This is because of its favorable effects on engine performance and pollutant emissions. The natural gas fueled engine provided the same performance as the diesel engine, met R49 emission standards, and showed very low smoke levels. On the other hand, it is well known that internal combustion engines emit some components that are harmful for human health, such as carbonyl compounds and polycyclic aromatic hydrocarbons (PAH). This paper shows the results of carbonyl compounds and PAH emissions analysis for a heavy-duty Otto cycle engine fueled with natural gas. The engine was tested using the R49 cycle that is used to measure the regulated emissions. The test analysis has been compared with an analysis of a diesel engine, tested under the same conditions. Total PAH emissions from the CNG engine were about three orders of magnitude lower than from the diesel engine. Formaldehyde emission from the CNG engine was about ten times as much as from the diesel engine, while emissions of other carbonyl compounds were comparable

  18. The ir emission features: Emission from PAH (Polycyclic Aromatic Hydrocarbons) molecules and amorphous carbon particles

    Energy Technology Data Exchange (ETDEWEB)

    Allamandola, L.J.; Tielens, A.G.G.M.; Barker, J.R.

    1986-01-01

    PAHs can have several forms in the interstellar medium. To assess the importance of each requires the availability of a collection of high quality, complete mid-ir interstellar emission spectra, a collection of laboratory spectra of PAH samples prepared under realistic conditions and a firm understanding of the microscopic emission mechanism. Given what we currently know about PAHs, the spectroscopic data suggests that there are at least two components which contribute to the interstellar emission spectrum: free molecule sized PAHs producing the narrow features and amorphous carbon particles (which are primarily made up of an irregular ''lattice'' of PAHs) contributing to the broad underlying components. An exact treatment of the ir fluorescence from highly vibrationally excited large molecules shows that species containing between 20 and 30 carbon atoms are responsible for the narrow features, although the spectra match more closely with the spectra of amorphous carbon particles. Since little is known about the spectroscopic properties of free PAHs and PAH clusters, much laboratory work is called for in conjunction with an observational program which focuses on the spatial characteristics of the spectra. In this way the distribution and evolution of carbon from molecule to particle can be traced. 38 refs., 9 figs.

  19. The ir emission features: Emission from PAH [Polycyclic Aromatic Hydrocarbons] molecules and amorphous carbon particles

    International Nuclear Information System (INIS)

    Allamandola, L.J.; Tielens, A.G.G.M.; Barker, J.R.

    1986-01-01

    PAHs can have several forms in the interstellar medium. To assess the importance of each requires the availability of a collection of high quality, complete mid-ir interstellar emission spectra, a collection of laboratory spectra of PAH samples prepared under realistic conditions and a firm understanding of the microscopic emission mechanism. Given what we currently know about PAHs, the spectroscopic data suggests that there are at least two components which contribute to the interstellar emission spectrum: free molecule sized PAHs producing the narrow features and amorphous carbon particles (which are primarily made up of an irregular ''lattice'' of PAHs) contributing to the broad underlying components. An exact treatment of the ir fluorescence from highly vibrationally excited large molecules shows that species containing between 20 and 30 carbon atoms are responsible for the narrow features, although the spectra match more closely with the spectra of amorphous carbon particles. Since little is known about the spectroscopic properties of free PAHs and PAH clusters, much laboratory work is called for in conjunction with an observational program which focuses on the spatial characteristics of the spectra. In this way the distribution and evolution of carbon from molecule to particle can be traced. 38 refs., 9 figs

  20. Developing the Infrared PAH Emission Bands Into Calibrated Probes of Astrophysical Conditions with The NASA Ames PAH IR Spectroscopic Database

    Science.gov (United States)

    Boersma, Christiaan

    We propose to quantitatively calibrate the PAH band strength ratios that have been traditionally used as qualitative proxies of PAH properties and linking PAH observables with local astrophysical conditions, thus developing PAHs into quantitative probes of astronomical environments. This will culminate in a toolbox (calibration charts) that can be used by PAH experts and non-PAH experts alike to unlock the information hidden in PAH emission sources that are part of the Spitzer and ISO archives. Furthermore, the proposed work is critical to mine the treasure trove of information JWST will return as it will capture, for the first time, the complete mid-infrared (IR) PAH spectrum with fully resolved features, through a single aperture, and along single lines-of-sight; making it possible to fully extract the information contained in the PAH spectra. In short, the work proposed here represents a major step in enabling the astronomical PAH model to reach its full potential as a diagnostic of the physical and chemical conditions in objects spanning the Universe. Polycyclic aromatic hydrocarbons (PAHs), a common and important reservoir of accessible carbon across the Universe, play an intrinsic part in the formation of stars, planets and possibly even life itself. While most PAH spectra appear quite similar, they differ in detail and contain a wealth of untapped information. Thanks to recent advances in laboratory studies and computer-based calculations of PAH spectra, the majority of which have been made at NASA Ames, coupled with the astronomical modeling tools we have developed, we can interpret the spectral details at levels never before possible. This enables us to extract local physical conditions and track subtle changes in these conditions at levels previously impossible. Building upon the tools and paradigms developed as part of the publicly available NASA Ames PAH IR Spectroscopic Database (PAHdb; www.astrochem.org/pahdb/), the purpose of our proposed research is

  1. Study of PAH emission from the solid fuels combustion in residential furnaces

    International Nuclear Information System (INIS)

    Kakareka, Sergey V.; Kukharchyk, Tamara I.; Khomich, Valery S.

    2005-01-01

    The procedure for and results of a test study of polycyclic aromatic hydrocarbon (PAH) emission from a few types of solid fuels combustion in residential furnaces of various designs typical for Belarus are discussed. Greatest levels of PAH emission were detected from domestic wastes and wood waste combustion. Lowest levels of PAH emission are from peat briquette combustion. It was found that PAH concentration in off-gases from firewood combustion also varies significantly depending on the type of wood: the highest values of PAH are typical for waste gases from birch firewood combustion in comparison with pine firewood combustion. Draft PAH emission factors are proposed with intended application for emission inventory of such installations

  2. Biodiesel emissions profile in modern diesel vehicles. Part 2: Effect of biodiesel origin on carbonyl, PAH, nitro-PAH and oxy-PAH emissions.

    Science.gov (United States)

    Karavalakis, Georgios; Boutsika, Vasiliki; Stournas, Stamoulis; Bakeas, Evangelos

    2011-01-15

    In the present study, the effects of different biodiesel blends on the unregulated emissions of a Euro 4 compliant passenger car were examined. Two fresh and two oxidized biodiesel fuels of different source materials were blended with an ultra low sulphur automotive diesel fuel at proportions of 10, 20, and 30% v/v. Emission measurements were conducted on a chassis dynamometer with a constant volume sampling (CVS) technique, over the New European Driving Cycle (NEDC) and the Artemis driving cycles. The experimental results revealed that the addition of biodiesel led to important increases in most carbonyl compounds. Sharp increases were observed with the use of the oxidized biodiesel blends, especially those prepared from used frying oil methyl esters. Similar to carbonyl emissions, most PAH compounds increased with the addition of the oxidized biodiesel blends. It can be assumed that the presence of polymerization products and cyclic acids, along with the degree of unsaturation were the main factors that influenced carbonyl and PAH emissions profile. Copyright © 2010 Elsevier B.V. All rights reserved.

  3. Major gaseous and PAH emissions from a fluidized-bed combustor firing rice husk with high combustion efficiency

    International Nuclear Information System (INIS)

    Janvijitsakul, Kasama; Kuprianov, Vladimir I.

    2008-01-01

    This experimental work investigated major gaseous (CO and NO x ) and PAH emissions from a 400 kW th fluidized-bed combustor with a cone-shaped bed (referred to as 'conical FBC') firing rice husk with high, over 99%, combustion efficiency. Experimental tests were carried out at the fuel feed rate of 80 kg/h for different values of excess air (EA). As revealed by the experimental results, EA had substantial effects on the axial CO and NO x concentration profiles and corresponding emissions from the combustor. The concentration (mg/kg-ash) and specific emission (μg/kW h) of twelve polycyclic aromatic hydrocarbons (PAHs), acenaphthylene, fluorene, phenanthrene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenz[a,h]anthracene and indeno[1,2,3-cd]pyrene, were quantified in this work for different size fractions of ash emitted from the conical FBC firing rice husk at EA = 20.9%. The total PAHs emission was found to be predominant for the coarsest ash particles, due to the effects of a highly developed internal surface in a particle volume. The highest emission was shown by acenaphthylene, 4.1 μg/kW h, when the total yield of PAHs via fly ash was about 10 μg/kW h. (author)

  4. Infrared absorption and emission characteristics of interstellar PAHs [Polycyclic Aromatic Hydrocarbon

    International Nuclear Information System (INIS)

    Allamandola, L.J.; Tielens, A.G.G.M.; Barker, J.R.

    1986-01-01

    The mid-infrared interstellar emission spectrum with features at 3050, 1610, 1300, 1150, and 885 cm -1 (3.28, 6.2, 7.7, 8.7 and 11.3 microns) is discussed in terms of the Polycyclic Aromatic Hydrocarbon (PAH) hypothesis. This hypothesis is based on the suggestive, but inconclusive comparison between the interstellar emission spectrum with the infrared absorption and Raman spectra of a few PAHs. The fundamental vibrations of PAHs and PAH-like species which determine the ir and Raman properties are discussed. Interstellar ir band emission is due to relaxation from highly vibrationally excited PAHs which have been excited by ultraviolet photons. The excitation/emission process is described in general and the ir fluorescence from one PAH, chrysene, is traced in detail. Generally, there is sufficient energy to populate several vibrational levels in each mode. Molecular vibrational potentials are anharmonic and emission from these higher levels will fall at lower frequencies and produce weak features to the red of the stronger fundamentals. This process is also described and can account for some spectroscopic details of the interstellar emission spectra previously unexplained. Analysis of the interstellar spectrum shows that PAHs containing between 20 and 30 carbon atoms are responsible for the emission. 43 refs., 11 figs

  5. Infrared absorption and emission characteristics of interstellar PAHs (Polycyclic Aromatic Hydrocarbon)

    Energy Technology Data Exchange (ETDEWEB)

    Allamandola, L.J.; Tielens, A.G.G.M.; Barker, J.R.

    1986-01-01

    The mid-infrared interstellar emission spectrum with features at 3050, 1610, 1300, 1150, and 885 cm/sup -1/ (3.28, 6.2, 7.7, 8.7 and 11.3 microns) is discussed in terms of the Polycyclic Aromatic Hydrocarbon (PAH) hypothesis. This hypothesis is based on the suggestive, but inconclusive comparison between the interstellar emission spectrum with the infrared absorption and Raman spectra of a few PAHs. The fundamental vibrations of PAHs and PAH-like species which determine the ir and Raman properties are discussed. Interstellar ir band emission is due to relaxation from highly vibrationally excited PAHs which have been excited by ultraviolet photons. The excitation/emission process is described in general and the ir fluorescence from one PAH, chrysene, is traced in detail. Generally, there is sufficient energy to populate several vibrational levels in each mode. Molecular vibrational potentials are anharmonic and emission from these higher levels will fall at lower frequencies and produce weak features to the red of the stronger fundamentals. This process is also described and can account for some spectroscopic details of the interstellar emission spectra previously unexplained. Analysis of the interstellar spectrum shows that PAHs containing between 20 and 30 carbon atoms are responsible for the emission. 43 refs., 11 figs.

  6. Cooking with Fire: The Mutagenicity- and PAH-Emission ...

    Science.gov (United States)

    Emissions from solid fuels used for cooking cause ~4 million premature deaths per year. Advanced solid-fuel cookstoves are a potential solution, but they should be assessed by appropriate performance indicators, including biological effects. We evaluated two categories of solid-fuel cookstoves for 8 pollutant- and 4 mutagenicity-emission factors, correlated the mutagenicity-emission factors, and compared them to those of other combustion emissions. We burned red oak in a 3-stone fire (TSF), a natural-draft stove (NDS), and a forced-draft stove (FDS); we combusted propane as a liquified petroleum gas control fuel. We determined emission factors based on useful energy (megajoules delivered, MJd) for carbon monoxide, nitrogen oxides (NOx), black carbon, methane, total hydrocarbons, 32 polycyclic aromatic hydrocarbons, PM2.5, levoglucosan (a wood-smoke marker), and mutagenicity in Salmonella. Other than NOx the emission factors per MJd correlated highly among each other (r2 ≥ 0.92); NOx correlated 0.58-0.76 with the other emission factors. Excluding NOx, the NDS and FDS reduced the emission factors on average 68 and 92%, respectively, relative to the TSF. Nonetheless, the mutagenicity-emission factor based on fuel energy used (MJthermal) for the most efficient stove (FDS) was intermediate to that of a large diesel bus engine and a small diesel generator. Both mutagenicity- and pollutant-emission factors may be informative for characterizing cookstove

  7. Prediction of HS Soderberg plant PAH emissions from a laboratory evaluation of a pitch

    Energy Technology Data Exchange (ETDEWEB)

    Castonguay, L.; Mirtchi, A. A.; Proulx, A. L.; Savard, G.; Simard, E.; Steward, N.; Tremblay, C. [Alcan International Ltd., Arvida Research and Development Centre, Jonquiere, PQ (Canada)

    1998-12-31

    The presence of certain polycyclic aromatic hydrocarbons (PAHs) in coal tar pitch has been identified as a possible limit to the long-term viability of horizontal stud (HS) Soderberg technology, a technology of importance in the aluminum industry. This paper presents the results of a comparative study of pitch PAH content and HS Soderberg cell emissions. Laboratory results are compared with plant emissions for two regular and low PAH pitches with the same softening points. The results indicate the existence of a correlation between pitch PAH content and cell emission, which is valid for regular tar pitches, low tar pitches, as well as for hybrid pitches. These findings make it possible to predict the quantity and distribution of HS Soderberg cell PAH emissions from the analysis of PAHs in the pitch. The results also justify the conclusion that the emission of genotoxic compounds from pitch in the HS Soderberg technology can be decreased by using a pitch with low PAH content. 4 refs., 5 tabs., 5 figs.

  8. Characteristics of polycyclic aromatic hydrocarbon (PAH) emissions from a UH-1H helicopter engine and its impact on the ambient environment

    Science.gov (United States)

    Chen, Yu-Cheng; Lee, Wen-Jhy; Uang, Shi-Nian; Lee, Su-Hsing; Tsai, Perng-Jy

    The objective of this study is to characterize the emissions of polycyclic aromatic hydrocarbons (PAHs) from a UH-1H helicopter turboshaft engine and its impact on the ambient environment. Five power settings of the ground idle (GI), fly idle (FI), beed band check (BBC), inlet guide vane (IGV), and take off (TO) were selected and samples were collected from the exhaust by using an isokinetic sampling system. Twenty-two PAH compounds were analyzed by gas chromatograph (GC)/MS. We found the mean total PAH concentration in the exhaust of the UH-1H engine (843 μg m -3) is 1.05-51.7 times in magnitude higher than those of the heavy-duty diesel (HDD) engine, motor vehicle engine, and F101 aircraft engine. Two- and three-ringed PAHs account for 97.5% of total PAH emissions from the UH-1H engine. The mean total PAH and total BaP eq emission factors for the UH-1H engine (63.4 and 0.309 mg L -1·fuel) is 1.65-23.4 and 1.30-7.54 times in magnitude higher than those for the motor vehicle engine, HDD engine, and F101 aircraft engine. The total emission level of the single PAH compound, BaP, for the UH-1H engine (EL BaP) during one landing and take off (LTO) cycle (2.19 mg LTO -1) was higher than the European Commission standard (1.24 mg LTO -1) suggesting that appropriate measures should be taken to reduce PAH emissions from UH-1H engines in the future.

  9. Variations of emission characterization of PAHs emitted from different utility boilers of coal-fired power plants and risk assessment related to atmospheric PAHs

    International Nuclear Information System (INIS)

    Wang, Ruwei; Liu, Guijian; Zhang, Jiamei

    2015-01-01

    Coal-fired power plants (CFPPs) represent important source of atmospheric PAHs, however, their emission characterization are still largely unknown. In this work, the concentration, distribution and gas-particle partitioning of PM_1_0- and gas-phase PAHs in flue gas emitted from different coal-fired utility boilers were investigated. Moreover, concentration and distribution in airborne PAHs from different functional areas of power plants were studied. People's inhalatory and dermal exposures to airborne PAHs at these sites were estimated and their resultant lung cancer and skin cancer risks were assessed. Results indicated that the boiler capacity and operation conditions have significant effect on PAH concentrations in both PM_1_0 and gas phases due to the variation of combustion efficiency, whereas they take neglected effect on PAH distributions. The wet flue gas desulphurization (WFGD) takes significant effect on the scavenging of PAH in both PM_1_0 and gas phases, higher scavenging efficiency were found for less volatile PAHs. PAH partitioning is dominated by absorption into organic matter and accompanied by adsorption onto PM_1_0 surface. In addition, different partitioning mechanism is observed for individual PAHs, which is assumed arising from their chemical affinity and vapor pressure. Risk assessment indicates that both inhalation and dermal contact greatly contribute to the cancer risk for CFPP workers and nearby residents. People working in workshop are exposed to greater inhalation and dermal exposure risk than people living in nearby vicinity and working office. - Highlights: • PAH distribution in PM_1_0 and gas phases primarily depend on the vapor pressure. • Combustion conditions and WFGD show typical effects on PAH level and profile. • PAH partitioning is dominated by absorption and also accompanied by adsorption. • Individual PAHs show different partitioning mechanisms in PM_1_0- and gas-phases. • People in workshop suffer greater cancer

  10. Variations of emission characterization of PAHs emitted from different utility boilers of coal-fired power plants and risk assessment related to atmospheric PAHs

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ruwei [CAS Key Laboratory of Crust-Mantle and the Environment, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, Anhui (China); State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, The Chinese Academy of Sciences, Xi' an 710075, Shanxi (China); Liu, Guijian, E-mail: lgj@ustc.edu.cn [CAS Key Laboratory of Crust-Mantle and the Environment, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, Anhui (China); State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, The Chinese Academy of Sciences, Xi' an 710075, Shanxi (China); Zhang, Jiamei [CAS Key Laboratory of Crust-Mantle and the Environment, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, Anhui (China)

    2015-12-15

    Coal-fired power plants (CFPPs) represent important source of atmospheric PAHs, however, their emission characterization are still largely unknown. In this work, the concentration, distribution and gas-particle partitioning of PM{sub 10}- and gas-phase PAHs in flue gas emitted from different coal-fired utility boilers were investigated. Moreover, concentration and distribution in airborne PAHs from different functional areas of power plants were studied. People's inhalatory and dermal exposures to airborne PAHs at these sites were estimated and their resultant lung cancer and skin cancer risks were assessed. Results indicated that the boiler capacity and operation conditions have significant effect on PAH concentrations in both PM{sub 10} and gas phases due to the variation of combustion efficiency, whereas they take neglected effect on PAH distributions. The wet flue gas desulphurization (WFGD) takes significant effect on the scavenging of PAH in both PM{sub 10} and gas phases, higher scavenging efficiency were found for less volatile PAHs. PAH partitioning is dominated by absorption into organic matter and accompanied by adsorption onto PM{sub 10} surface. In addition, different partitioning mechanism is observed for individual PAHs, which is assumed arising from their chemical affinity and vapor pressure. Risk assessment indicates that both inhalation and dermal contact greatly contribute to the cancer risk for CFPP workers and nearby residents. People working in workshop are exposed to greater inhalation and dermal exposure risk than people living in nearby vicinity and working office. - Highlights: • PAH distribution in PM{sub 10} and gas phases primarily depend on the vapor pressure. • Combustion conditions and WFGD show typical effects on PAH level and profile. • PAH partitioning is dominated by absorption and also accompanied by adsorption. • Individual PAHs show different partitioning mechanisms in PM{sub 10}- and gas-phases. • People in

  11. Emission characterization and δ"1"3C values of parent PAHs and nitro-PAHs in size-segregated particulate matters from coal-fired power plants

    International Nuclear Information System (INIS)

    Wang, Ruwei; Yousaf, Balal; Sun, Ruoyu; Zhang, Hong; Zhang, Jiamei; Liu, Guijian

    2016-01-01

    Highlights: • pPAHs and NPAHs were strongly associated with PM_1_–_2_._5 and PM_1 compared with PM_2_._5_–_1_0. • Combustion conditions and WFGD showed typical effects on PAH level and profile. • Diagnostic ratio of PAH was to indicative of emission sources to a certain degree. • δ"1"3C values of PAHs were useful for differentiating coal combustion source. • δ"1"3C values of PAHs were unable to differentiate coal-processing sources. - Abstract: The objective of this study was to characterize parent polycyclic aromatic hydrocarbons (pPAHs) and their nitrated derivatives (NPAHs) in coarse (PM_2_._5_–_1_0), intermediate (PM_1_–_2_._5) and fine (PM_1) particulate matters emitted from coal-fired power plants (CFPPs) in Huainan, China. The diagnostic ratios and the stable carbon isotopic approaches to characterize individual PAHs were applied in order to develop robust tools for tracing the origins of PAHs in different size-segregated particular matters (PMs) emitted CFPP coal combustion. The concentrations of PAH compounds in flue gas emissions varied greatly, depending on boiler types, operation and air pollution control device (APCD) conditions. Both pPAHs and NPAHs were strongly enriched in PM_1_–_2_._5 and PM_1. In contrary to low molecular weight (LMW) PAHs, high molecular weight (HMW) PAHs were more enriched in finer PMs. The PAH diagnostic ratios in size-segregated PMs are small at most cases, highlighting their potential application in tracing CFPP emitted PAHs attached to different sizes of PMs. Yet, substantial uncertainty still exists to directly apply PAH diagnostic ratios as emission tracers. Although the stable carbon isotopic composition of PAH molecular was useful in differentiating coal combustion emissions from other sources such as biomass combustion and vehicular exhausts, it was not feasible to differentiate isotopic fractionation processes such as low-temperature carbonization, high-temperature carbonization, gasification and

  12. Emission characterization and δ{sup 13}C values of parent PAHs and nitro-PAHs in size-segregated particulate matters from coal-fired power plants

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ruwei [CAS Key Laboratory of Crust-Mantle Materials and the Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026 (China); State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, The Chinese Academy of Sciences, Xi’an 710075 Shaanxi (China); Yousaf, Balal; Sun, Ruoyu [CAS Key Laboratory of Crust-Mantle Materials and the Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026 (China); Zhang, Hong [Anhui Department of Environmental Protection, Anhui Academy of Environmental Science, Hefei 230071 (China); Zhang, Jiamei [CAS Key Laboratory of Crust-Mantle Materials and the Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026 (China); Liu, Guijian, E-mail: lgj@ustc.edu.cn [CAS Key Laboratory of Crust-Mantle Materials and the Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026 (China); State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, The Chinese Academy of Sciences, Xi’an 710075 Shaanxi (China)

    2016-11-15

    Highlights: • pPAHs and NPAHs were strongly associated with PM{sub 1–2.5} and PM{sub 1} compared with PM{sub 2.5–10}. • Combustion conditions and WFGD showed typical effects on PAH level and profile. • Diagnostic ratio of PAH was to indicative of emission sources to a certain degree. • δ{sup 13}C values of PAHs were useful for differentiating coal combustion source. • δ{sup 13}C values of PAHs were unable to differentiate coal-processing sources. - Abstract: The objective of this study was to characterize parent polycyclic aromatic hydrocarbons (pPAHs) and their nitrated derivatives (NPAHs) in coarse (PM{sub 2.5–10}), intermediate (PM{sub 1–2.5}) and fine (PM{sub 1}) particulate matters emitted from coal-fired power plants (CFPPs) in Huainan, China. The diagnostic ratios and the stable carbon isotopic approaches to characterize individual PAHs were applied in order to develop robust tools for tracing the origins of PAHs in different size-segregated particular matters (PMs) emitted CFPP coal combustion. The concentrations of PAH compounds in flue gas emissions varied greatly, depending on boiler types, operation and air pollution control device (APCD) conditions. Both pPAHs and NPAHs were strongly enriched in PM{sub 1–2.5} and PM{sub 1}. In contrary to low molecular weight (LMW) PAHs, high molecular weight (HMW) PAHs were more enriched in finer PMs. The PAH diagnostic ratios in size-segregated PMs are small at most cases, highlighting their potential application in tracing CFPP emitted PAHs attached to different sizes of PMs. Yet, substantial uncertainty still exists to directly apply PAH diagnostic ratios as emission tracers. Although the stable carbon isotopic composition of PAH molecular was useful in differentiating coal combustion emissions from other sources such as biomass combustion and vehicular exhausts, it was not feasible to differentiate isotopic fractionation processes such as low-temperature carbonization, high

  13. Single photon infrared emission spectroscopy: a study of IR emission from UV laser excited PAHs between 3 and 15 micrometers

    Science.gov (United States)

    Cook, D. J.; Schlemmer, S.; Balucani, N.; Wagner, D. R.; Harrison, J. A.; Steiner, B.; Saykally, R. J.

    1998-01-01

    Single-photon infrared emission spectroscopy (SPIRES) has been used to measure emission spectra from polycyclic aromatic hydrocarbons (PAHs). A supersonic free-jet expansion has been used to provide emission spectra of rotationally cold and vibrationally excited naphthalene and benzene. Under these conditions, the observed width of the 3.3-micrometers (C-H stretch) band resembles the bandwidths observed in experiments in which emission is observed from naphthalene with higher rotational energy. To obtain complete coverage of IR wavelengths relevant to the unidentified infrared bands (UIRs), UV laser-induced desorption was used to generate gas-phase highly excited PAHs. Lorentzian band shapes were convoluted with the monochromator-slit function in order to determine the widths of PAH emission bands under astrophysically relevant conditions. Bandwidths were also extracted from bands consisting of multiple normal modes blended together. These parameters are grouped according to the functional groups mostly involved in the vibration, and mean bandwidths are obtained. These bandwidths are larger than the widths of the corresponding UIR bands. However, when the comparison is limited to the largest PAHs studied, the bandwidths are slightly smaller than the corresponding UIR bands. These parameters can be used to model emission spectra from PAH cations and cations of larger PAHs, which are better candidate carriers of the UIRs.

  14. Variations of emission characterization of PAHs emitted from different utility boilers of coal-fired power plants and risk assessment related to atmospheric PAHs.

    Science.gov (United States)

    Wang, Ruwei; Liu, Guijian; Zhang, Jiamei

    2015-12-15

    Coal-fired power plants (CFPPs) represent important source of atmospheric PAHs, however, their emission characterization are still largely unknown. In this work, the concentration, distribution and gas-particle partitioning of PM10- and gas-phase PAHs in flue gas emitted from different coal-fired utility boilers were investigated. Moreover, concentration and distribution in airborne PAHs from different functional areas of power plants were studied. People's inhalatory and dermal exposures to airborne PAHs at these sites were estimated and their resultant lung cancer and skin cancer risks were assessed. Results indicated that the boiler capacity and operation conditions have significant effect on PAH concentrations in both PM10 and gas phases due to the variation of combustion efficiency, whereas they take neglected effect on PAH distributions. The wet flue gas desulphurization (WFGD) takes significant effect on the scavenging of PAH in both PM10 and gas phases, higher scavenging efficiency were found for less volatile PAHs. PAH partitioning is dominated by absorption into organic matter and accompanied by adsorption onto PM10 surface. In addition, different partitioning mechanism is observed for individual PAHs, which is assumed arising from their chemical affinity and vapor pressure. Risk assessment indicates that both inhalation and dermal contact greatly contribute to the cancer risk for CFPP workers and nearby residents. People working in workshop are exposed to greater inhalation and dermal exposure risk than people living in nearby vicinity and working office. Copyright © 2015. Published by Elsevier B.V.

  15. Infrared emission from a polycyclic aromatic hydrocarbon (PAH) excited by ultraviolet laser

    International Nuclear Information System (INIS)

    Cherchneff, I.; Barker, J.R.

    1989-01-01

    The infrared fluorescence spectrum from the C-H stretch modes of vibrationally excited azulene (C10H8), a PAH was measured in the laboratory. PAHs are candidates as carriers of the unidentified infrared emission bands that are observed in many astronomical objects associated with dust and ultraviolet light. In the present experiment, gas phase azulene was excited with light from a 308 nm pulsed laser, and the infrared emission spectrum was time-resolved and wavelength-resolved. Moreover, the infrared absorption spectrum of gas phase azulene was obtained using an FTIR spectrometer. The laboratory emission spectrum resembles observed infrared emission spectra from the interstellar medium, providing support for the hypothesis that PAHs are the responsible carriers. The azulene C-H stretch emission spectrum is more asymmetric than the absorption spectrum, probably due to anharmonicity of levels higher than nu = 1. 36 refs

  16. Hot gas cleaning in power stations by using electron beam technology. Influence on PAH emissions

    International Nuclear Information System (INIS)

    Callen, M.S.; de la Cruz, M.T.; Mastral, A.M.; Murillo, R.; Marinov, S.; Stefanova, M.

    2007-01-01

    The Electron Beam Technology (EBT), proven treatment for SO 2 and NO x removal, is applied to different power stations as a hot gas cleaning system. In this paper, an assessment of this technique installed in a Bulgarian power station on organic emissions is analyzed. The Polycyclic Aromatic Hydrocarbons (PAH) content, not only emitted in the gas phase but also trapped in the solid phase, has been carried out before and after the irradiation. The main aim has been to know whether the EBT affects organic emissions, like PAH, as it happens with inorganic pollutants, like SO 2 and NO x , studying EBT effects from an organic environmental point of view. The PAH quantification was performed by using a very sensitive analytical technique, gas chromatography with mass spectrometry mass spectrometry detection (GC-MS-MS). Results showed that PAH are influenced by the EBT showing a reduction of the most volatile PAH in the gas phase. With regard to the solid by-products obtained after the irradiation, fertilizers, similar PAH concentration to the fly ashes produced when no irradiation is applied were found. These fertilizers were considered like unpolluted soils being adequate for agriculture applications with PAH concentrations below the target value set up by the Dutch government. (author)

  17. Effect of upgraded diesel fuels and oxidation catalysts on emission properties, especially PAH and genotoxicity

    DEFF Research Database (Denmark)

    Johansen, Keld; Gabrielsson, Pär; Stavnsbjerg, Peter

    1997-01-01

    in an engine test bench and a full ECE R49 13 mode test was performed and 2) a VW GOLF 1.6 l engine was mounted in a car and a full transient FTP-75 test was performed. Regulated emissions and unregulated emissions as SOF, sulphur, nitrate, PAH in PM plus vapour phase were measured. Genotoxic activity...

  18. A CASE AGAINST SPINNING PAHS AS THE SOURCE OF THE ANOMALOUS MICROWAVE EMISSION

    Energy Technology Data Exchange (ETDEWEB)

    Hensley, Brandon S.; Draine, B. T. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Meisner, Aaron M., E-mail: brandon.s.hensley@jpl.nasa.gov [Berkeley Center for Cosmological Physics, Berkeley, CA 94720 (United States)

    2016-08-10

    We employ an all-sky map of the anomalous microwave emission (AME) produced by component separation of the microwave sky to study correlations between the AME and Galactic dust properties. We find that while the AME is highly correlated with all tracers of dust emission, the best predictor of the AME strength is the dust radiance. Fluctuations in the AME intensity per dust radiance are uncorrelated with fluctuations in the emission from polycyclic aromatic hydrocarbons (PAHs), casting doubt on the association between AME and PAHs. The PAH abundance is strongly correlated with the dust optical depth and dust radiance, consistent with PAH destruction in low density regions. We find that the AME intensity increases with increasing radiation field strength, at variance with predictions from the spinning dust hypothesis. Finally, the temperature dependence of the AME per dust radiance disfavors the interpretation of the AME as thermal emission. A reconsideration of other AME carriers, such as ultrasmall silicates, and other emission mechanisms, such as magnetic dipole emission, is warranted.

  19. Seasonal variation, spatial distribution and source apportionment for polycyclic aromatic hydrocarbons (PAHs) at nineteen communities in Xi'an, China: The effects of suburban scattered emissions in winter.

    Science.gov (United States)

    Wang, Jingzhi; Cao, Junji; Dong, Zhibao; Guinot, Benjamin; Gao, Meiling; Huang, Rujin; Han, Yongming; Huang, Yu; Ho, Steven Sai Hang; Shen, Zhenxing

    2017-12-01

    Seasonal variation and spatial distribution of PM 2.5 bound polycyclic aromatic hydrocarbons (PAHs) were investigated at urban residential, commercial area, university, suburban region, and industry in Xi'an, during summer and winter time at 2013. Much higher levels of total PAHs were obtained in winter. Spatial distributions by kriging interpolations principle showed that relative high PAHs were detected in western Xi'an in both summer and winter, with decreasing trends in winter from the old city wall to the 2 nd -3rd ring road except for the suburban region and industry. Coefficients of diversity and statistics by SPSS method demonstrated that PAHs in suburban have significant differences (t winter and summer in urban, which different with the suburban. The coal combustion was the main source for PAHs in suburban region, which accounted for 46.6% in winter and sharp decreased to 19.2% in summer. Scattered emissions from uncontrolled coal combustion represent an important source of PAHs in suburban in winter and there were about 135 persons in Xi'an will suffer from lung cancer for lifetime exposure at winter levels. Further studies are needed to specify the effluence of the scattered emission in suburban to the city and to develop a strategy for controlling those emissions and lighten possible health effects. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Effects of Co-Processing Sewage Sludge in the Cement Kiln on PAHs, Heavy Metals Emissions and the Surrounding Environment.

    Science.gov (United States)

    Lv, Dong; Zhu, Tianle; Liu, Runwei; Li, Xinghua; Zhao, Yuan; Sun, Ye; Wang, Hongmei; Zhang, Fan; Zhao, Qinglin

    2018-04-08

    To understand the effects of co-processing sewage sludge in the cement kiln on non-criterion pollutants emissions and its surrounding environment, the flue gas from a cement kiln stack, ambient air and soil from the background/downwind sites were collected in the cement plant. Polycyclic aromatic hydrocarbons (PAHs) and heavy metals of the samples were analyzed. The results show that PAHs in flue gas mainly exist in the gas phase and the low molecular weight PAHs are the predominant congener. The co-processing sewage sludge results in the increase in PAHs and heavy metals emissions, especially high molecular weight PAHs and low-volatile heavy metals such as Cd and Pb in the particle phase, while it does not change their compositions and distribution patterns significantly. The concentrations and their distributions of the PAHs and heavy metals between the emissions and ambient air have a positive correlation and the co-processing sewage sludge results in the increase of PAHs and heavy metals concentrations in the ambient air. The PAHs concentration level and their distribution in soil are proportional to those in the particle phase of flue gas, and the co-processing sewage sludge can accelerate the accumulation of the PAHs and heavy metals in the surrounding soil, especially high/middle molecular weight PAHs and low-volatile heavy metals.

  1. Estimation of the emission factors of PAHs by traffic with the model of atmospheric dispersion and deposition from heavy traffic road.

    Science.gov (United States)

    Ozaki, N; Tokumitsu, H; Kojima, K; Kindaichi, T

    2007-01-01

    In order to consider the total atmospheric loadings of the PAHs (polycyclic aromatic hydrocarbons) from traffic activities, the emission factors of PAHs were estimated and from the obtained emission factors and vehicle transportation statistics, total atmospheric loadings were integrated and the loadings into the water body were estimated on a regional scale. The atmospheric concentration of PAHs was measured at the roadside of a road with heavy traffic in the Hiroshima area in Japan. The samplings were conducted in summer and winter. Atmospheric particulate matters (fine particle, 0.6-7 microm; coarse particle, over 7 microm) and their PAH concentration were measured. Also, four major emission sources (gasoline and diesel vehicle emissions, tire and asphalt debris) were assumed for vehicle transportation activities, the chemical mass balance method was applied and the source partitioning at the roadside was estimated. Furthermore, the dispersion of atmospheric particles from the vehicles was modelled and the emission factors of the sources were determined by the comparison to the chemical mass balance results. Based on emission factors derived from the modelling, an atmospheric dispersion model of nationwide scale (National Institute of Advanced Industrial Science and Technology - Atmospheric Dispersion Model for Exposure and Risk assessment) was applied, and the atmospheric concentration and loading to the ground were calculated for the Hiroshima Bay watershed area.

  2. CO and PAH emissions from engines operating on producer gas

    DEFF Research Database (Denmark)

    Ahrenfeldt, Jesper

    2005-01-01

    High carbon monoxide (CO) emission from gas engines fueled by producer gas is a concerning problem in the struggle to make biomass gasification for heat and power production a success. The standing regulations concerning CO emissions from gas engine based power plants in most EU countries are so ...

  3. Polycyclic aromatic hydrocarbons (PAH) and diesel engine emission (elemental carbon) inside a car and a subway train.

    Science.gov (United States)

    Fromme, H; Oddoy, A; Piloty, M; Krause, M; Lahrz, T

    1998-06-30

    Significant concentrations of potentially harmful substances can be present in the interior of vehicles. The main sources of PAHs and elemental carbon (EC) inside a car are likely to be combustion emissions, especially from coal and traffic. The same sources can also be important for the interior of a subway train for which there are specific sources in the tunnel system, for example diesel engines. Twice, in summer 1995 and winter 1996 polycyclic aromatic hydrocarbons (PAH) and diesel motor emission (estimated as elemental carbon) were determined in the interior of a car (a 2-year-old VW Golf with a three-way catalytic converter) and in the passenger compartment of a subway train (below ground). On each sampling day (in total 16 daily measurements in the car and 16 in the subway) the substances were determined in the breathing zone of the passengers from 07:00 h to 16:00 h under different meteorologic conditions (winter- and summertime). The car followed the route of the subway from the western Berlin borough of Spandau to the south-eastern borough of Neukölln, and back. The sampling represented a realistic exposure model for driving in a high traffic and polluted urban area. The electric subway train (also 2 years in use) connected the same parts of Berlin (31 km underground). The mean values obtained during the two measurement periods (summer/winter) inside the car were 1.0 and 3.2 ng/m3 for benzo[a]pyrene, 10.2 and 28.7 ng/m3 for total-measured-PAHs, 14.1 and 8.2 micrograms/m3 for EC and in the subway 0.7 and 4.0 ng/m3 for benzol[a]pyrene, 30.2 and 67.5 ng/m3 for total PAHs, 109 and 6.9 micrograms/m3 for EC. A comparison between subway and car exposures shows significantly higher concentrations of PAHs in the subway train, which can be explained by relatively high concentrations of fluoranthene and pyrene in the subway. So far a satisfactory explanation has not been found, but one source might be the wooden railway ties which were formerly preserved with tar

  4. Heat and PAHs Emissions in Indoor Kitchen Air and Its Impact on Kidney Dysfunctions among Kitchen Workers in Lucknow, North India.

    Science.gov (United States)

    Singh, Amarnath; Kamal, Ritul; Mudiam, Mohana Krishna Reddy; Gupta, Manoj Kumar; Satyanarayana, Gubbala Naga Venkata; Bihari, Vipin; Shukla, Nishi; Khan, Altaf Hussain; Kesavachandran, Chandrasekharan Nair

    2016-01-01

    Indoor air quality and heat exposure have become an important occupational health and safety concern in several workplaces including kitchens of hotels. This study investigated the heat, particulate matter (PM), total volatile organic compounds (TVOCs) and polycyclic aromatic hydrocarbons (PAHs) emissions in indoor air of commercial kitchen and its association with kidney dysfunctions among kitchen workers. A cross sectional study was conducted on 94 kitchen workers employed at commercial kitchen in Lucknow city, North India. A questionnaire-based survey was conducted to collect the personal and occupational history of the kitchen workers. The urine analysis for specific gravity and microalbuminuria was conducted among the study subjects. Indoor air temperature, humidity, wet/ dry bulb temperature and humidex heat stress was monitored during cooking activities at the kitchen. Particulate matter (PM) for 1 and 2.5 microns were monitored in kitchen during working hours using Hazdust. PAHS in indoor air was analysed using UHPLC. Urinary hydroxy-PAHs in kitchen workers were measured using GC/MS-MS. Higher indoor air temperature, relative humidity, PM1 and PM2.5 (pworkers (pworkers. Urinary PAH metabolites detected among kitchen workers were 1-NAP, 9-HF, 3-HF, 9-PHN and 1-OHP. Continuous heat exposure in kitchens due to cooking can alter kidney functions viz., high specific gravity of urine in kitchen workers. Exposure to PM, VOCs and PAHs in indoor air and presence of urinary PAHs metabolites may lead to inflammation, which can cause microalbuminuria in kitchen workers, as observed in the present study.

  5. Seasonal variation, spatial distribution and source apportionment for polycyclic aromatic hydrocarbons (PAHs) at nineteen communities in Xi'an, China: The effects of suburban scattered emissions in winter

    International Nuclear Information System (INIS)

    Wang, Jingzhi; Cao, Junji; Dong, Zhibao; Guinot, Benjamin; Gao, Meiling; Huang, Rujin; Han, Yongming; Huang, Yu

    2017-01-01

    Seasonal variation and spatial distribution of PM 2.5 bound polycyclic aromatic hydrocarbons (PAHs) were investigated at urban residential, commercial area, university, suburban region, and industry in Xi'an, during summer and winter time at 2013. Much higher levels of total PAHs were obtained in winter. Spatial distributions by kriging interpolations principle showed that relative high PAHs were detected in western Xi'an in both summer and winter, with decreasing trends in winter from the old city wall to the 2 nd -3rd ring road except for the suburban region and industry. Coefficients of diversity and statistics by SPSS method demonstrated that PAHs in suburban have significant differences (t < 0.05) with those in urban residential in both seasons. The positive Matrix Factorization (PMF) modeling indicated that biomass burning (31.1%) and vehicle emissions (35.9%) were main sources for PAHs in winter and summer in urban, which different with the suburban. The coal combustion was the main source for PAHs in suburban region, which accounted for 46.6% in winter and sharp decreased to 19.2% in summer. Scattered emissions from uncontrolled coal combustion represent an important source of PAHs in suburban in winter and there were about 135 persons in Xi'an will suffer from lung cancer for lifetime exposure at winter levels. Further studies are needed to specify the effluence of the scattered emission in suburban to the city and to develop a strategy for controlling those emissions and lighten possible health effects. - Highlights: • PM 2.5 bound PAHs were investigated in nineteen communities of Xi'an at 2013. • High amount of uncontrolled coal combustion were happened in suburban at winter. • About 135 persons in Xi'an will suffer from lung cancer for exposure at winter. - The high contribution of coal combustion for PAHs in suburban region demonstrated the high amount of scattered emissions in winter.

  6. PM10 emissions and PAHs: The importance of biomass type and combustion conditions.

    Science.gov (United States)

    Zosima, Angela T; Tzimou-Tsitouridou, Roxani D; Nikolaki, Spyridoula; Zikopoulos, Dimitrios; Ochsenkühn-Petropoulou, Maria Th

    2016-01-01

    The aim of the present work was to investigate the impact of biomass combustion with respect to conditions and fuel types on particle emissions (PM10) and their PAHs content. Special concern was on sampling, quantification and characterization of PM using different appliances, fuels and operating procedures. For this purpose different lab-scale burning conditions, two pellets stoves (8.5 and 10 kW) and one open fireplace were tested by using eight fuel types of biomass. An analytical method is described for the quantitative determination of 16 PAHs using liquid-liquid extraction and subsequent measurement by gas chromatography coupled to a mass spectrometer (GC-MS). Average PM10 emissions ranged from about 65 to 170 mg/m(3) at lab-scale combustions with flow oxygen at 13% in the exhaust gas, 85-220 mg/m(3) at 20% O2, 47-83 mg/m(3) at pellet stove of 10 kW, 34-69 mg/m(3) at pellet stove of 8.5 kW and 106-194 mg/m(3) at the open fireplace. The maximum permitted particle emission limit is 150 mg/m(3). Pellets originated from olive trees and from nonmixture trees were found to emit the lowest particulate matter in relation to the others, so they are considered healthiest and suitable for domestic heating reasons. In general, the results show that biomass open burning is an important PM10 and PAHs emission source.

  7. Field measurement on the emissions of PM, OC, EC and PAHs from indoor crop straw burning in rural China

    International Nuclear Information System (INIS)

    Wei, Siye; Shen, Guofeng; Zhang, Yanyan; Xue, Miao; Xie, Han; Lin, Pengchuan; Chen, Yuanchen; Wang, Xilong; Tao, Shu

    2014-01-01

    Field measurements were conducted to measure emission factors of particulate matter (EF PM ), organic carbon (EF OC ), elemental carbon (EF EC ), 28 parent polycyclic aromatic hydrocarbons (EF 28pPAHs ), and 4 oxygenated PAHs (EF 4oPAHs ) for four types of crop straws burned in two stoves with similar structure but different ages. The average EF PM , EF OC , EF EC , EF 28pPAHs , and EF 4oPAHs were 9.1 ± 5.7 (1.8–22 as range), 2.6 ± 2.9 (0.30–12), 1.1 ± 1.2 (0.086–5.5), 0.26 ± 0.19 (0.076–0.96), 0.011 ± 0.14 (1.3 × 10 −4 – 0.063) g/kg, respectively. Much high EF 28pPAHs was observed in field compared with the laboratory derived EFs and significant difference in EF 28pPAHs was identified among different crop residues, indicating considerable underestimation when laboratory derived EFs were used in the inventory. The field measured EF PM , EF OC , and EF EC were significantly affected by stove age and the EFs of carbonaceous particles for the 15-year old stove were approximately 2.5 times of those for the 1-year old stove. Highlights: • Field measurements provided more reliable data for the inventory. • Emissions from indoor crop residue burning were measured in field. • Much high PAHs emissions were found in field measurement in comparison with laboratory derived results. • Emissions of carbonaceous particulate matter increased by 2.5 times in the old stove compared that in a new stove. -- Emissions of incomplete combustion pollutants strongly affected by the fuel type and stove usage

  8. Emissions of PCDD/Fs, PCBs, and PAHs from a modern diesel engine equipped with catalyzed emission control systems.

    Science.gov (United States)

    Laroo, Christopher A; Schenk, Charles R; Sanchez, L James; McDonald, Joseph

    2011-08-01

    Exhaust emissions of 17 2,3,7,8-substituted chlorinated dibenzo-p-dioxin/furan (CDD/F) congeners, tetra-octa CDD/F homologues, 12 2005 WHO chlorinated biphenyls (CB) congeners, mono-nona CB homologues, and 19 polycyclic aromatic hydrocarbons (PAHs) from a model year 2008 Cummins ISB engine were investigated. Testing included configurations composed of different combinations of aftertreatment including a diesel oxidation catalyst (DOC), catalyzed diesel particulate filter (CDPF), copper zeolite urea selective catalytic reduction (SCR), iron zeolite SCR, and ammonia slip catalyst. Results were compared to a baseline engine out configuration. Testing included the use of fuel that contained the maximum expected chlorine (Cl) concentration of U.S. highway diesel fuel and a Cl level 1.5 orders of magnitude above. Results indicate there is no risk for an increase in polychlorinated dibenzo-p-dioxin/furan and polychlorinated biphenyl emissions from modern diesel engines with catalyzed aftertreatment when compared to engine out emissions for configurations tested in this program. These results, along with PAH results, compare well with similar results from modern diesel engines in the literature. The results further indicate that polychlorinated dibenzo-p-dioxin/furan emissions from modern diesel engines both with and without aftertreatment are below historical values reported in the literature as well as the current inventory value.

  9. Diurnal variations of ambient particulate wood burning emissions and their contribution to the concentration of Polycyclic Aromatic Hydrocarbons (PAHs) in Seiffen, Germany

    Science.gov (United States)

    Poulain, L.; Iinuma, Y.; Müller, K.; Birmili, W.; Weinhold, K.; Brüggemann, E.; Gnauk, T.; Hausmann, A.; Löschau, G.; Wiedensohler, A.; Herrmann, H.

    2011-12-01

    Residential wood burning is becoming an increasingly important cause of air quality problems since it has become a popular source of alternative energy to fossil fuel. In order to characterize the contribution of residential wood burning to local particle pollution, a field campaign was organized at the village of Seiffen (Saxony, Germany). During this campaign, an Aerosol Mass Spectrometer (AMS) was deployed in parallel to a PM1 high volume filter sampler. The AMS mass spectra were analyzed using Positive Matrix Factorization (PMF) to obtain detailed information about the organic aerosol (OA). Biomass-burning organic aerosol (BBOA), Hydrocarbon-like organic aerosol (HOA), and Oxygenated Organic Aerosol (OOA) were identified and represented 20%, 17% and 62% of total OA, respectively. Additionally, Polycyclic Aromatic Hydrocarbons (PAH) were measured by the AMS with an average concentration of 10 ng m-3 and short term events of extremely high PAH concentration (up to 500 ng m-3) compared to the mean PAH value were observed during the whole measurement period. A comparison with the results from PM1 filter samples showed that the BBOA factor and the AMS PAH are good indicators of the total concentration of the different monosaccharide anhydrides and PAH measured on the filter samples. Based on its low correlation with CO and the low car traffic, the HOA factor was considered to be related to residential heating using liquid fuel. An influence of the time of the week (week vs. weekend) on the diurnal profiles of the different OA components was observed. The weekdays were characterized by two maxima; a first one early in the morning and a stronger one in the evening. During the weekend days, the different OA components principally reached only one maximum in the afternoon. Finally, the PAH emitted directly from residential wood combustion was estimated to represent 1.5% of the total mass of the BBOA factor and around 62% of the total PAH concentration measured at

  10. Diurnal variations of ambient particulate wood burning emissions and their contribution to the concentration of Polycyclic Aromatic Hydrocarbons (PAHs in Seiffen, Germany

    Directory of Open Access Journals (Sweden)

    L. Poulain

    2011-12-01

    around 62% of the total PAH concentration measured at Seiffen. This result highlights the important contribution of residential wood combustion to air quality and PAH emissions at the sampling place, which might have a significant impact on human health. Moreover, it also emphasizes the need for a better time resolution of the chemical characterization of toxic particulate compounds in order to provide more information on variations of the different sources through the days as well as to better estimate the real human exposure.

  11. Emission characteristics for gaseous- and size-segregated particulate PAHs in coal combustion flue gas from circulating fluidized bed (CFB) boiler.

    Science.gov (United States)

    Wang, Ruwei; Liu, Guijian; Sun, Ruoyu; Yousaf, Balal; Wang, Jizhong; Liu, Rongqiong; Zhang, Hong

    2018-07-01

    The partitioning behavior of polycyclic aromatic hydrocarbons (PAHs) between gaseous and particulate phases from coal-fired power plants (CFPPs) is critically important to predict PAH removal by dust control devices. In this study, 16 US-EPA priority PAHs in gaseous and size-segregated particulate phases at the inlet and outlet of the fabric filter unit (FFs) of a circulating fluidized bed (CFB) boiler were analyzed. The partitioning mechanisms of PAHs between gaseous and particulate phases and in particles of different size classes were investigated. We found that the removal efficiencies of PAHs are 45.59% and 70.67-89.06% for gaseous and particulate phases, respectively. The gaseous phase mainly contains low molecular weight (LMW) PAHs (2- and 3-ring PAHs), which is quite different from the particulate phase that mainly contains medium and high molecular weight (MMW and HMW) PAHs (4- to 6-ring PAHs). The fractions of LMW PAHs show a declining trend with the decrease of particle size. The gas-particle partitioning of PAHs is primarily controlled by organic carbon absorption, in addition, it has a clear dependence on the particle sizes. Plot of log (TPAH/PM) against logD p shows that all slope values were below -1, suggesting that PAHs were mainly adsorbed to particulates. The adsorption effect of PAHs in size-segregated PMs for HMW PAHs is more evident than LMW PAHs. The particle size distributions (PSDs) of individual PAHs show that most of PAHs exhibit bi-model structures, with one mode peaking in the accumulation size range (2.1-1.1 μm) and another mode peaking in coarse size range (5.8-4.7 μm). The intensities of these two peaks vary in function of ring number of PAHs, which is likely attributed to Kelvin effect that the less volatile HMW PAH species preferentially condense onto the finer particulates. The emission factor of PAHs was calculated as 3.53 mg/kg of coal burned, with overall mean EF PAH of 0.55 and 2.98 mg/kg for gaseous and particulate

  12. Heat and PAHs Emissions in Indoor Kitchen Air and Its Impact on Kidney Dysfunctions among Kitchen Workers in Lucknow, North India.

    Directory of Open Access Journals (Sweden)

    Amarnath Singh

    Full Text Available Indoor air quality and heat exposure have become an important occupational health and safety concern in several workplaces including kitchens of hotels. This study investigated the heat, particulate matter (PM, total volatile organic compounds (TVOCs and polycyclic aromatic hydrocarbons (PAHs emissions in indoor air of commercial kitchen and its association with kidney dysfunctions among kitchen workers. A cross sectional study was conducted on 94 kitchen workers employed at commercial kitchen in Lucknow city, North India. A questionnaire-based survey was conducted to collect the personal and occupational history of the kitchen workers. The urine analysis for specific gravity and microalbuminuria was conducted among the study subjects. Indoor air temperature, humidity, wet/ dry bulb temperature and humidex heat stress was monitored during cooking activities at the kitchen. Particulate matter (PM for 1 and 2.5 microns were monitored in kitchen during working hours using Hazdust. PAHS in indoor air was analysed using UHPLC. Urinary hydroxy-PAHs in kitchen workers were measured using GC/MS-MS. Higher indoor air temperature, relative humidity, PM1 and PM2.5 (p<0.001 was observed in the kitchen due to cooking process. Indoor air PAHs identified are Napthalene, fluorine, acenaphthene, phenanthrene, pyrene, chrysene and indeno [1,2,3-cd pyrene. Concentrations of all PAHs identified in kitchen were above the permissible OSHA norms for indoor air. Specific gravity of urine was significantly higher among the kitchen workers (p<0.001 as compared to the control group. Also, the prevalence of microalbuminuria was higher (p<0.001 among kitchen workers. Urinary PAH metabolites detected among kitchen workers were 1-NAP, 9-HF, 3-HF, 9-PHN and 1-OHP. Continuous heat exposure in kitchens due to cooking can alter kidney functions viz., high specific gravity of urine in kitchen workers. Exposure to PM, VOCs and PAHs in indoor air and presence of urinary PAHs

  13. Do 16 Polycyclic Aromatic Hydrocarbons Represent PAH Air Toxicity?

    Science.gov (United States)

    Samburova, Vera; Zielinska, Barbara; Khlystov, Andrey

    2017-08-15

    Estimation of carcinogenic potency based on analysis of 16 polycyclic aromatic hydrocarbons (PAHs) ranked by U.S. Environmental Protection Agency (EPA) is the most popular approach within scientific and environmental air quality management communities. The majority of PAH monitoring projects have been focused on particle-bound PAHs, ignoring the contribution of gas-phase PAHs to the toxicity of PAH mixtures in air samples. In this study, we analyzed the results of 13 projects in which 88 PAHs in both gas and particle phases were collected from different sources (biomass burning, mining operation, and vehicle emissions), as well as in urban air. The aim was to investigate whether 16 particle-bound U.S. EPA priority PAHs adequately represented health risks of inhalation exposure to atmospheric PAH mixtures. PAH concentrations were converted to benzo(a)pyrene-equivalent (BaPeq) toxicity using the toxic equivalency factor (TEF) approach. TEFs of PAH compounds for which such data is not available were estimated using TEFs of close isomers. Total BaPeq toxicities (∑ 88 BaPeq) of gas- and particle-phase PAHs were compared with BaPeq toxicities calculated for the 16 particle-phase EPA PAH (∑ 16EPA BaPeq). The results showed that 16 EPA particle-bound PAHs underrepresented the carcinogenic potency on average by 85.6% relative to the total (gas and particle) BaPeq toxicity of 88 PAHs. Gas-phase PAHs, like methylnaphthalenes, may contribute up to 30% of ∑ 88 BaPeq. Accounting for other individual non-EPA PAHs (i.e., benzo(e)pyrene) and gas-phase PAHs (i.e., naphthalene, 1- and 2-methylnaphthalene) will make the risk assessment of PAH-containing air samples significantly more accurate.

  14. Total hemispherical emissivity of Inconel 718

    Energy Technology Data Exchange (ETDEWEB)

    Keller, Benjamin P.; Nelson, Shawn E.; Walton, Kyle L.; Ghosh, Tushar K.; Tompson, Robert V.; Loyalka, Sudarshan K., E-mail: LoyalkaS@missouri.edu

    2015-06-15

    Highlights: • We have measured the total hemispherical emissivity for Inconel 718 from about 600–1250 K. • Oxidation in air at 1073 K resulted in an increase in emissivity. • Sandblasting of Inconel 718 was also observed to increase the emissivity. • Coating of graphite powder onto the ‘as-received’ Inconel 718 showed no increase in the emissivity. • Coating of graphite powder onto the 220 grit sandblasted Inconel 718 did show an increase in emissivity. - Abstract: Total hemispherical emissivity for Inconel 718 was measured in anticipation of its application in Very High Temperature Gas Reactors (VHTRs). A majority of current emissivity data for Inconel 718 is in the form of spectral measurements. The data presented here were obtained with an experimental apparatus based on the standard ASTM C835-06 for total hemispherical emittance. Measurements of Inconel 718 were made for four different surface types including: (i) ‘as-received’ from the manufacturer, (ii) oxidized in air and humidified helium, (iii) sandblasted with aluminum oxide powder, and (iv) with a thin coating of nuclear grade graphite powder (grade NGB-18). The emissivity for the ‘as-received’ sample ranged from 0.21 to 0.28 in the temperature interval from 760 K to 1275 K. Oxidation in air at 1073 K resulted in an increase in emissivity into the range from 0.2 at 650 K to 0.52 at 1200 K. There was no dependence on the oxidation times studied here. Oxidation with humidified helium at 1073 K produced less of an increase in emissivity than the oxidation in air but there was an increase up to the range from 0.2 at 600 K to 0.35 at 1200 K. Sandblasting of Inconel 718 was also observed to increase the emissivity up to the range from 0.43 at 780 K to 0.53 at 1270 K when 60 grit sized powder was used and up to the range from 0.45 at 683 K to 0.57 at 1267 K when 120 and 220 grit sized powders were used. Coating of graphite powder onto the ‘as-received’ Inconel 718 showed no increase

  15. THE FAR-INFRARED EMISSION FROM THE Mg+-PAH SPECIES

    International Nuclear Information System (INIS)

    Bauschlicher, Charles W. Jr.; Ricca, Alessandra

    2009-01-01

    The far-infrared (FIR) spectra of several Mg + -PAH species are studied using density functional theory. The Mg + -PAH stretching mode, regardless of the polycyclic aromatic hydrocarbon (PAH) species, carries a reasonable intensity and tends to fall in a narrow range near 40 μm. Because the bands tend to fall at very similar frequencies, the average spectra of several Mg + -PAH species produce a broadband with an intensity that is about 20% of the well known C-H out-of-plane bending mode. In contrast, an average of seven large compact pure PAHs has no FIR bands that carry any significant intensity.

  16. The Infrared Spectra of Polycyclic Aromatic Hydrocarbons with Excess Peripheral H Atoms (H(sub n)-PAHs) and their Relation to the 3.4 and 6.9 Micrometer PAH Emission Features

    Science.gov (United States)

    Sandford, Scott A.; Bernstein, Max P.; Materese, Christopher K.

    2013-01-01

    A population of polycyclic aromatic hydrocarbons (PAHs) and related materials are thought to be responsible for the family of infrared emission features that are seen towards a wide variety of astrophysical environments. A potentially important subclass of these materials are polycyclic aromatic hydrocarbons whose edges contain excess H atoms (H(sub n)-PAHs). While it has been suggested that this type of compound may be present in the interstellar population, it has been difficult to properly assess this possibility because of a lack of suitable infrared laboratory spectra to assist with analysis of the astronomical data. We present the 4000-500 cm(exp -1) (2.5-20 micrometers) infrared spectra of 23 H(sub n)-PAHs and related molecules isolated in argon matrices, under conditions suitable for use in the interpretation of astronomical data. The spectra of molecules with mixed aromatic and aliphatic domains show unique characteristics that distinguish them from their fully aromatic PAH equivalents. We discuss the changes to the spectra of these types of molecules as they transition from fully aromatic to fully aliphatic forms. The implications for the interpretation of astronomical spectra are discussed with specific emphasis on the 3.4 and 6.9 micrometer features. Laboratory data is compared with emission spectra from IRAS 21282+5050, an object with normal PAH emission features, in addition to IRAS 22272+5435 and IRAS 0496+3429, two protoplanetary nebulae with abnormally large 3.4 micrometer features. We show that 'normal' PAH emission objects contain relatively few H(sub n)-PAHs in their emitter populations, but less evolved protoplanetary nebulae may contain significant abundances of these molecules.

  17. Indoor emission, dispersion and exposure of total particle-bound polycyclic aromatic hydrocarbons during cooking

    Science.gov (United States)

    Gao, Jun; Jian, Yating; Cao, Changsheng; Chen, Lei; Zhang, Xu

    2015-11-01

    Cooking processes highly contribute to indoor polycyclic aromatic hydrocarbon (PAH) pollution. High molecular weight and potentially carcinogenic PAHs are generally found attached to small particles, i.e., particulate phase PAHs (PPAHs). Due to the fact that indoor particle dynamics have been clear, describing the indoor dynamics of cooking-generated PPAHs within a specific time span is possible. This paper attempted to quantify the dynamic emission rate, simultaneous spatial dispersion and individual exposure of PPAHs using a cooking source. Experiments were conducted in a real-scale kitchen chamber to elucidate the time-resolved emission and effect of edible oil temperature and mass. Numerical simulations based on indoor particle dynamics were performed to obtain the spatial dispersion and individual inhalation intake of PPAHs under different emission and ventilation conditions. The present work examined the preheating cooking stage, at which edible oil is heated up to beyond its smoke point. The dynamic emission rate peak point occurred much earlier than the oil heating temperature. The total PPAH emission ranged from 2258 to 6578 ng upon heating 40-85 g of edible oil. The overall intake fraction by an individual within a period of 10 min, including 3 min for heating and 7 min for natural cooling, was generally ∼1/10,000. An important outcome of this work was that the overall intake fraction could be represented by multiplying the range hood escape efficiency by the inhalation-to-ventilation rate ratio, which would be no greater than the same ratio. The methodology and results of this work were extendible for the number-based assessment of PPAHs. This work is expected to help us understand the health risks due to inhalation exposure to cooking-generated PPAHs in the kitchen.

  18. Modeling the Anomalous Microwave Emission with Spinning Nanoparticles: No PAHs Required

    Energy Technology Data Exchange (ETDEWEB)

    Hensley, Brandon S. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Draine, B. T., E-mail: brandon.s.hensley@jpl.nasa.gov [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)

    2017-02-20

    In light of recent observational results indicating an apparent lack of correlation between the anomalous microwave emission (AME) and mid-infrared emission from polycyclic aromatic hydrocarbons, we assess whether rotational emission from spinning silicate and/or iron nanoparticles could account for the observed AME without violating observational constraints on interstellar abundances, ultraviolet extinction, and infrared emission. By modifying the SpDust code to compute the rotational emission from these grains, we find that nanosilicate grains could account for the entirety of the observed AME, whereas iron grains could be responsible for only a fraction, even for extreme assumptions on the amount of interstellar iron concentrated in ultrasmall iron nanoparticles. Given the added complexity of contributions from multiple grain populations to the total spinning dust emission, as well as existing uncertainties due to the poorly constrained grain size, charge, and dipole moment distributions, we discuss generic, carrier-independent predictions of spinning dust theory and observational tests that could help identify the AME carrier(s).

  19. Distributions and Concentrations of PAHs in Hong Kong Soils

    International Nuclear Information System (INIS)

    Zhang, H.B.; Luo, Y.M.; Wong, M.H.; Zhao, Q.G.; Zhang, G.L.

    2006-01-01

    Surface soil (0-10 cm) samples from 53 sampling sites including rural and urban areas of Hong Kong were collected and analyzed for 16 EPA priority polycyclic aromatic hydrocarbons (PAHs). Total PAH concentrations were in the range of 7.0-410 μg kg -1 (dry wt), with higher concentrations in urban soils than that in rural soils. The three predominant PAHs were Fluoranthene, Naphthalene and Pyrene in rural soils, while Fluoranthene, Naphthalene and Benzo(b + k)fluoranthene dominated the PAHs of urban soils. The values of PAHs isomer indicated that biomass burning might be the major origin of PAHs in rural soils, but vehicular emission around the heavy traffic roads might contribute to the soil PAHs in urban areas. A cluster analysis was performed and grouped the detectable PAHs under 4 clusters, which could be indicative of the PAHs with different origins and PAHs affected by soil organic carbon contents respectively. - Baseline information is provided on levels, distributions and possible sources of PAHs in Hong Kong soils

  20. Time-resolved analysis of particle emissions from residential biomass combustion - Emissions of refractory black carbon, PAHs and organic tracers

    Science.gov (United States)

    Nielsen, Ingeborg E.; Eriksson, Axel C.; Lindgren, Robert; Martinsson, Johan; Nyström, Robin; Nordin, Erik Z.; Sadiktsis, Ioannis; Boman, Christoffer; Nøjgaard, Jacob K.; Pagels, Joakim

    2017-09-01

    Time-resolved particle emissions from a conventional wood stove were investigated with aerosol mass spectrometry to provide links between combustion conditions, emission factors, mixing state of refractory black carbon and implications for organic tracer methods. The addition of a new batch of fuel results in low temperature pyrolysis as the fuel heats up, resulting in strong, short-lived, variable emission peaks of organic aerosol-containing markers of anhydrous sugars, such as levoglucosan (fragment at m/z 60). Flaming combustion results in emissions dominated by refractory black carbon co-emitted with minor fractions of organic aerosol and markers of anhydrous sugars. Full cycle emissions are an external mixture of larger organic aerosol-dominated and smaller thinly coated refractory black carbon particles. A very high burn rate results in increased full cycle mass emission factors of 66, 2.7, 2.8 and 1.3 for particulate polycyclic aromatic hydrocarbons, refractory black carbon, total organic aerosol and m/z 60, respectively, compared to nominal burn rate. Polycyclic aromatic hydrocarbons are primarily associated with refractory black carbon-containing particles. We hypothesize that at very high burn rates, the central parts of the combustion zone become air starved, leading to a locally reduced combustion temperature that reduces the conversion rates from polycyclic aromatic hydrocarbons to refractory black carbon. This facilitates a strong increase of polycyclic aromatic hydrocarbons emissions. At nominal burn rates, full cycle emissions based on m/z 60 correlate well with organic aerosol, refractory black carbon and particulate matter. However, at higher burn rates, m/z 60 does not correlate with increased emissions of polycyclic aromatic hydrocarbons, refractory black carbon and organic aerosol in the flaming phase. The new knowledge can be used to advance source apportionment studies, reduce emissions of genotoxic compounds and model the climate impacts of

  1. Development of a screening method for the determination of total polynuclear aromatic hydrocarbons (PAH) in water and wastewater

    International Nuclear Information System (INIS)

    Riggin, R.; Strup, P.; Billets, S.

    1983-01-01

    Polynuclear aromatic hydrocarbons (PAHs) represent an important class of organic compounds from an environmental standpoint, due to known human carcinogenicity of some members. Consequently, there is a great need for monitoring the PAH concentration of a variety of media, including water and industrial wastewater. Recently, the United States Environmental Protection Agency (U.S. EPA) developed a sensitive analytical method, designated Test Method 610, for the determination of priority pollutant PAHs in aqueous industrial discharges. This method employs reversed phase high performance liquid chromatography (HPLC) with ultraviolet (UV) and fluorescence detection to determine all sixteen priority pollutant PAHs in a single chromatographic separation

  2. Atmospheric concentrations and air–soil gas exchange of polycyclic aromatic hydrocarbons (PAHs) in remote, rural village and urban areas of Beijing–Tianjin region, North China

    Science.gov (United States)

    Wang, Wentao; Simonich, Staci; Giri, Basant; Chang, Ying; Zhang, Yuguang; Jia, Yuling; Tao, Shu; Wang, Rong; Wang, Bin; Li, Wei; Cao, Jun; Lu, Xiaoxia

    2013-01-01

    Forty passive air samplers were deployed to study the occurrence of gas and particulate phase PAHs in remote, rural village and urban areas of Beijing–Tianjin region, North China for four seasons (spring, summer, fall and winter) from 2007 to 2008. The influence of emissions on the spatial distribution pattern of air PAH concentrations was addressed. In addition, the air–soil gas exchange of PAHs was studied using fugacity calculations. The median gaseous and particulate phase PAH concentrations were 222 ng/m3 and 114 ng/m3, respectively, with a median total PAH concentration of 349 ng/m3. Higher PAH concentrations were measured in winter than in other seasons. Air PAH concentrations measured at the rural villages and urban sites in the northern mountain region were significantly lower than those measured at sites in the southern plain during all seasons. However, there was no significant difference in PAH concentrations between the rural villages and urban sites in the northern and southern areas. This urban–rural PAH distribution pattern was related to the location of PAH emission sources and the population distribution. The location of PAH emission sources explained 56%–77% of the spatial variation in ambient air PAH concentrations. The annual median air–soil gas exchange flux of PAHs was 42.2 ng/m2/day from soil to air. Among the 15 PAHs measured, acenaphthylene (ACY) and acenaphthene (ACE) contributed to more than half of the total exchange flux. Furthermore, the air–soil gas exchange fluxes of PAHs at the urban sites were higher than those at the remote and rural sites. In summer, more gaseous PAHs volatilized from soil to air because of higher temperatures and increased rainfall. However, in winter, more gaseous PAHs deposited from air to soil due to higher PAH emissions and lower temperatures. The soil TOC concentration had no significant influence on the air–soil gas exchange of PAHs. PMID:21669328

  3. The impact of co-combustion of polyethylene plastics and wood in a small residential boiler on emissions of gaseous pollutants, particulate matter, PAHs and 1,3,5- triphenylbenzene.

    Science.gov (United States)

    Tomsej, Tomas; Horak, Jiri; Tomsejova, Sarka; Krpec, Kamil; Klanova, Jana; Dej, Milan; Hopan, Frantisek

    2018-04-01

    The aim of this study was to simulate a banned but widely spread practice of co-combustion of plastic with wood in a small residential boiler and to quantify its impact on emissions of gaseous pollutants, particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), and 1,3,5-triphenylbenzene (135TPB), a new tracer of polyethylene plastic combustion. Supermarket polyethylene shopping bags (PE) and polyethylene terephthalate bottles (PET) were burnt as supplementary fuels with beech logs (BL) in an old-type 20 kW over-fire boiler both at a nominal and reduced heat output. An impact of co-combustion was more pronounced at the nominal heat output: an increase in emissions of PM, total organic carbon (TOC), toxic equivalent (TEQ) of 7 carcinogenic PAHs (c-PAHs) and a higher ratio of c-PAHs TEQ in particulate phase was observed during co-combustion of both plastics. 135TPB was found in emissions from both plastics both at a nominal and reduced output. In contrast to findings reported in the literature, 135TPB was a dominant compound detected by mass spectrometry on m/z 306 exclusively in emissions from co-combustion of PE. Surprisingly, six other even more abundant compounds of unknown identity were found on this m/z in emissions from co-combustion of PET. One of these unknown compounds was identified as p-quaterphenyl (pQ). Principal component analysis revealed strong correlation among 135TPB, pQ and five unknown compounds. pQ seems to be suitable tracers of polyethylene terephthalate plastic co-combustion, while 135TPB proved its suitability to be an all-purpose tracer of polyethylene plastics combustion. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Emissions of PCDD/Fs, PCBs, and PAHs from legacy on-road heavy-duty diesel engines.

    Science.gov (United States)

    Laroo, Christopher A; Schenk, Charles R; Sanchez, L James; McDonald, Joseph; Smith, Peter L

    2012-11-01

    Exhaust emissions of seventeen 2,3,7,8-substituted polychlorinated dibenzo-p-dioxin/furan (PCDD/F) congeners, tetra-octa PCDD/F homologues, 12 WHO 2005 polychlorinated biphenyl (PCB) congeners, mono-nona chlorinated biphenyl homologues, and 19 polycyclic aromatic hydrocarbons (PAHs) from three legacy diesel engines were investigated. The three engines tested were a 1985 model year GM 6.2J-series engine, a 1987 model year Detroit Diesel Corporation 6V92 engine, and a 1993 model year Cummins L10 engine. Results were compared to United States' mobile source inventory for on-road diesel engines, as well as historic and modern diesel engine emission values. The test fuel contained chlorine at 9.8 ppm which is 1.5 orders of magnitude above what is found in current diesel fuel and 3900 ppm sulfur to simulate fuels that would have been available when these engines were produced. Results indicate PCDD/F emissions of 13.1, 7.1, and 13.6 pg International Toxic Equivalency (I-TEQ)L(-1) fuel consumed for the three engines respectively, where non-detects are equal to zero. This compares with a United States' mobile source on-road diesel engine inventory value of 946 pg I-TEQL(-1) fuel consumed and 1.28 pg I-TEQL(-1) fuel consumed for modern engines equipped with a catalyzed diesel particle filter and urea selective catalytic reduction. PCB emissions are 2 orders of magnitude greater than modern diesel engines. PAH results are representative of engines from this era based on historical values and are 3-4 orders of magnitude greater than modern diesel engines. Published by Elsevier Ltd.

  5. Characteristics of particulate PAHs during a typical haze episode in Guangzhou, China

    Science.gov (United States)

    Tan, Jihua; Guo, Songjun; Ma, Yongliang; Duan, Jingchun; Cheng, Yuan; He, Kebin; Yang, Fumo

    2011-10-01

    The concentrations of polycyclic aromatic hydrocarbons (PAHs) in PM 2.5 and TSP were measured in Guangzhou during a typical haze episode. This episode included NH (non-haze, 3 days), HFN (haze when air masses from north and northeast, 6 days) and HFS (haze when air masses from south, 4 days). The air quality in HFN was much worse than that in NH and HFS. The total average concentrations of PAHs in PM 2.5 were 13.25 ng m -3, 59.82 ng m -3 and 13.09 ng m -3 in NH, HFN and HFS, respectively. It indicated PAH pollution had been substantially aggravated by HFN. PAHs(5 + 6) were the most abundant compounds in HFN and HFS, which accounted for 55-75% of total concentration of PAHs, while PAHs(3 + 4) were the most abundant compounds in NH, which accounted for 54-67% of total concentration of PAHs. TEF (Toxic Equivalency Factors)-adjusted concentrations of 13 particulate PAHs were very high in HFN, indicating high health risks to humans for PAH exposure in HFN. The characteristic ratios of PAHs indicated coal combustion and traffic emission were the major contributors to PAHs in HFN and HFS. The concentrations of particulate PAHs in haze episode were strongly affected by wind speed and wind direction. PAHs in NH could be from long-range transport with high north wind speed, while local emission could be the main contributor of particle-associated PAHs in HFN. The transport speed of air masses was found to play an important role on PAH concentrations.

  6. Incidence of real-world automotive parent and halogenated PAH in urban atmosphere.

    Science.gov (United States)

    Gao, Pan-Pan; Zhao, Yi-Bo; Ni, Hong-Gang

    2018-06-01

    This study reports results from a tunnel experiment impact of real-world traffic-related particle and gas parent and halogenated polycyclic aromatic hydrocarbons (PAHs and HPAHs) on urban air. The traffic related emission characteristics and subsequent environmental behavior of these compounds were investigated. To understand the significance of real-world transport emissions to the urban air, traffic-related mass emissions of PAHs and HPAHs were estimated based on measured emission factors. According to our results, PAHs and HPAHs emissions via particulate phase were greater than those via gaseous phase; particles in 2.1-3.3 μm size fraction, have the major contribution to particulate PAHs and HPAHs emissions. Over all, contribution of traffic-related emission of PAHs (only ∼3% of the total PAHs emission in China) is an overstated source of PAHs pollution in China. Actually, exhaust pipe emission contributed much less than the total traffic-related emission of pollutants. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. C2D spitzer-IRS spectra of disks around T tauri stars : II. PAH emission features

    NARCIS (Netherlands)

    Geers, V. C.; Augereau, J. -C; Pontoppidan, K. M.; Dullemond, C. P.; Visser, R.; Kessler-Silacci, J. E.; Evans, N. J.; van Dishoeck, E. F.; Blake, G. A.; Boogert, A. C. A.; Lahuis, F.; Merin, B.

    Aims. We search for Polycyclic Aromatic Hydrocarbon (PAH) features towards young low-mass (T Tauri) stars and compare them with surveys of intermediate mass (Herbig Ae/Be) stars. The presence and strength of the PAH features are interpreted with disk radiative transfer models exploring the PAH

  8. Coal-tar-based sealcoated pavement: A major PAH source to urban stream sediments

    International Nuclear Information System (INIS)

    Witter, Amy E.; Nguyen, Minh H.; Baidar, Sunil; Sak, Peter B.

    2014-01-01

    We used land-use analysis, PAH concentrations and assemblages, and multivariate statistics to identify sediment PAH sources in a small (∼1303 km 2 ) urbanizing watershed located in South-Central, Pennsylvania, USA. A geographic information system (GIS) was employed to quantify land-use features that may serve as PAH sources. Urban PAH concentrations were three times higher than rural levels, and were significantly and highly correlated with combined residential/commercial/industrial land use. Principal components analysis (PCA) was used to group sediments with similar PAH assemblages, and correlation analysis compared PAH sediment assemblages to common PAH sources. The strongest correlations were observed between rural sediments (n = 7) and coke-oven emissions sources (r = 0.69–0.78, n = 5), and between urban sediments (n = 22) and coal-tar-based sealcoat dust (r = 0.94, n = 47) suggesting that coal-tar-based sealcoat is an important urban PAH source in this watershed linked to residential and commercial/industrial land use. -- Highlights: • Total PAH concentrations were measured at 35 sites along an urbanizing land-use gradient. • PAH concentrations increased with increasing urban land-use. • Urban land-use metrics were measured at three spatial scales using GIS. • PAH assemblages indicate coal-tar-based sealcoat is a major urban PAH source. • PAH assemblages indicate coke-oven emissions are an important rural PAH source. -- Coal-tar-based sealcoated pavement is a major PAH source to urban freshwater stream sediments in south-central Pennsylvania, USA

  9. Emission of BTEX and PAHs from molding sands with furan cold setting resins containing different contents of free furfuryl alcohol during production of cast iron

    Directory of Open Access Journals (Sweden)

    Mariusz Holtzer

    2015-11-01

    Full Text Available At present, furan resin is the largest selling no-bake system of moulding sands. The most commonly used furan no-bake binders (FNB are condensation products of furfuryl alcohol (FA urea, formaldehyde and phenol. They are generally cured by exposure to organic sulfonic acids. FNB provide excellent mold and core strength, cure rapidly and allow the sand to be reclaimed at fairly high yields, generally 75%-80%, especially in applications where due allowance is made for the need to keep total sulfur content below 0.1%. However, due to probable carcinogenic properties of furfuryl alcohol, the EU Directive limits the content of this substance (in a monomer form in resin to 25%. The classification of furfuryl alcohol and the resulting furan resin products has changed from "harmful" to "toxic" by inhalation? The aim of this study was to determine the effect of free furfuryl alcohol content in the resin on the emission of harmful substances from the BTEX (Benzene Toluene Ethylbenzene & Xylene and PAHs (polycyclic aromatic hydrocarbon group exposed to high temperature and how it affects the emissions allowance of reclaimed sand in the matrix. Three resins from a leading manufacturer were examined, which contain a free furfuryl alcohol content of 71%-72%, about 50% and < 25%, respectively. The hardener for each resin was 65% aqueous solution of paratoluenesulfonic acid. Tests were carried out in semi-industrial conditions where liquid cast-iron was poured into sample sand mold at 1,350 ìC. The matrix of the studied sands was reclaimed in the amount of 0, 50%, 100%, respectively. With the increase of free furfuryl alcohol content, the volume of evolved gases decreased. For all resins the main component from the BTEX group dominating in the emitted gases was benzene; however toluene also appeared in the amount of a few percentages. In contrast, ethylbenzene and xylenes occurred only in the gases emitted from resin-bonded sands with the largest furfuryl

  10. Polycyclic aromatic hydrocarbons (PAHs) in exhaust emissions from diesel engines powered by rapeseed oil methylester and heated non-esterified rapeseed oil

    Science.gov (United States)

    Vojtisek-Lom, Michal; Czerwinski, Jan; Leníček, Jan; Sekyra, Milan; Topinka, Jan

    2012-12-01

    Polycyclic aromatic hydrocarbons (PAHs) of exhaust emissions were studied in four direct-injection turbocharged four-cylinder diesel engines, with power ratings of 90-136 kW. The engines were operated on biodiesel (B-100), a blend of 30% biodiesel in diesel fuel (B-30), and heated rapeseed oil (RO) in two independent laboratories. Diesel particle filters (DPF) and selective catalytic reduction (SCR) systems were used with B-30 and B-100. Concentrations of individual PAHs sampled in different substrates (quartz, borosilicate fiber and fluorocarbon membrane filters, polyurethane foam) were analyzed using different methods. Benzo[a]pyrene toxic equivalents (BaP TEQ) were calculated using different sets of toxic equivalency factors (TEF). Operation on B-100 without aftertreatment devices, compared to diesel fuel, yielded a mean reduction in PAHs of 73%, consistent across engines and among TEF used. A lower PAH reduction was obtained using B-30. The BaP TEQ reductions on DPF were 91-99% using B-100, for one non-catalyzed DPF, and over 99% in all other cases. The BaP TEQ for heated RO were higher than those for B-100 and one half lower to over twice as high as that of diesel fuel. B-100 and RO samples featured, compared to diesel fuel, a relatively high share of higher molecular weight PAH and a relatively low share of lighter PAHs. Using different sets of TEF or different detection methods did not consistently affect the observed effect of fuels on BaP TEQ. The compilation of multiple tests was helpful for discerning emerging patterns. The collection of milligrams of particulate matter per sample was generally needed for quantification of all individual PAHs.

  11. CO and PAH Emissions from Engines Operating on Biomass Producer Gas

    DEFF Research Database (Denmark)

    Ahrenfeldt, Jesper; Jensen, Torben Kvist; Henriksen, Ulrik Birk

    2003-01-01

    High carbon monoxide (CO) emission from gas engines fueled by producer gas is a concerning problem in the struggle to make biomass gasification for heat and power production a success. The standing regulations concerning CO emissions from producer gas engine based power plants in most EU countrie...

  12. Cloud deposition of PAHs at Mount Lushan in southern China

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ruixia [School of Environmental Science and Engineering, Shandong University, Jinan, 250100 (China); Wang, Yan, E-mail: wangyan405@gmail.com [School of Environmental Science and Engineering, Shandong University, Jinan, 250100 (China); Li, Hongli, E-mail: lihongli1225@163.com [Environmental Monitoring Central Station of Shandong Province, Jinan, 250101 (China); Yang, Minmin; Sun, Lei [School of Environmental Science and Engineering, Shandong University, Jinan, 250100 (China); Wang, Tao [Department of Civil and Structural Engineering, The Hong Kong Polytechnic University, Hong Kong (China); Wang, Wenxing [Environment Research Institute, Shandong University, Jinan, 250100 (China)

    2015-09-01

    Cloud water samples were collected from Mount Lushan, a high alpine area of southern China, and analyzed using GC–MS to investigate the concentration levels, seasonal variations, particle-dissolved phase partitioning, ecological risk of PAHs and its relationship to the atmosphere and rainwater. The average concentration of total (dissolved + particle) PAHs in cloud water was 819.90 ng/L, which ranged from 2.30 ng/L for DbA to 295.38 ng/L for PhA. PhA (33.11%) contributed the most individual PAHs, followed by Flu (28.24%). Distinct seasonal variations in the total PAHs measured in this research had a higher concentration during the spring and a lower concentration during the summer. When cloud events occurred, the concentration of the atmospheric PAHs of the two phases decreased. The contribution from the gaseous phase of total PAHs in the air to the dissolved phase in cloud water was up to 60.43%, but the particulate phase in the air only contributed 39.57% to the total scavenging. The contribution of total PAHs from the atmosphere to clouds is higher in the gaseous phase than in the particulate phase. A comparative study of the concentrations of cloud water and the closest rain water revealed that the PAH concentration in rainwater was 1.80 times less than that of cloud water and that the dominant individual compounds in cloud water and rainwater were PhA and Flu. A total of 81.27% of the PAHs in cloud samples and 72.21% of the PAHs in rain samples remained in the dissolved phase. Ecological risk assessment indicated that PAHs in cloud water in spring and summer caused a certain degree of ecosystem risk and the mean ecosystem risk in spring was higher than that in summer. - Highlights: • The site is in the high pollution emission area, having many sources of PAHs around. • Mount Lushan is a unique site for cloud chemistry monitoring. • Atmospheric PAHs mostly deposited and transferred into cloud water. • Special case showed PAHs are more concentrated in

  13. Cloud deposition of PAHs at Mount Lushan in southern China

    International Nuclear Information System (INIS)

    Wang, Ruixia; Wang, Yan; Li, Hongli; Yang, Minmin; Sun, Lei; Wang, Tao; Wang, Wenxing

    2015-01-01

    Cloud water samples were collected from Mount Lushan, a high alpine area of southern China, and analyzed using GC–MS to investigate the concentration levels, seasonal variations, particle-dissolved phase partitioning, ecological risk of PAHs and its relationship to the atmosphere and rainwater. The average concentration of total (dissolved + particle) PAHs in cloud water was 819.90 ng/L, which ranged from 2.30 ng/L for DbA to 295.38 ng/L for PhA. PhA (33.11%) contributed the most individual PAHs, followed by Flu (28.24%). Distinct seasonal variations in the total PAHs measured in this research had a higher concentration during the spring and a lower concentration during the summer. When cloud events occurred, the concentration of the atmospheric PAHs of the two phases decreased. The contribution from the gaseous phase of total PAHs in the air to the dissolved phase in cloud water was up to 60.43%, but the particulate phase in the air only contributed 39.57% to the total scavenging. The contribution of total PAHs from the atmosphere to clouds is higher in the gaseous phase than in the particulate phase. A comparative study of the concentrations of cloud water and the closest rain water revealed that the PAH concentration in rainwater was 1.80 times less than that of cloud water and that the dominant individual compounds in cloud water and rainwater were PhA and Flu. A total of 81.27% of the PAHs in cloud samples and 72.21% of the PAHs in rain samples remained in the dissolved phase. Ecological risk assessment indicated that PAHs in cloud water in spring and summer caused a certain degree of ecosystem risk and the mean ecosystem risk in spring was higher than that in summer. - Highlights: • The site is in the high pollution emission area, having many sources of PAHs around. • Mount Lushan is a unique site for cloud chemistry monitoring. • Atmospheric PAHs mostly deposited and transferred into cloud water. • Special case showed PAHs are more concentrated in

  14. Mass balance-based regression modeling of PAHs accumulation in urban soils, role of urban development

    International Nuclear Information System (INIS)

    Peng, Chi; Wang, Meie; Chen, Weiping; Chang, Andrew C.

    2015-01-01

    We investigated the polycyclic aromatic hydrocarbons (PAHs) contents in 68 soils samples collected at housing developments that represent different length of development periods across Beijing. Based on the data, we derived a mass balanced mathematical model to simulate the dynamics of PAH accumulations in urban soils as affected by the urban developments. The key parameters were estimated by fitting the modified mass balance model to the data of PAH concentrations vs. building age of the sampling green area. The total PAH concentrations would increase from the baseline of 267 ng g −1 to 3631 ng g −1 during the period of 1978–2048. It showed that the dynamic changes in the rates of accumulations of light and heavy PAH species were related to the shifting of sources of fuels, combustion efficiencies, and amounts of energy consumed during the course of development. - Highlights: • Introduced a mass balance model for soil PAHs accumulation with urbanization. • Reconstructed the historical data of PAH accumulation in soil of Beijing, China. • The soil PAH concentrations would be doubled in the following 40 years. • The composition of PAH emissions were shifting to light PAH species. - Introduced a regression modeling approach to predict the changes of PAH concentrations in urban soil

  15. Uptake of Total Petroleum Hydrocarbon (TPH) and Polycyclic Aromatic Hydrocarbons (PAHs) by Oryza sativa L. Grown in Soil Contaminated with Crude Oil.

    Science.gov (United States)

    Patowary, Rupshikha; Patowary, Kaustuvmani; Devi, Arundhuti; Kalita, Mohan Chandra; Deka, Suresh

    2017-01-01

    The purpose of this study was to determine whether total petroleum hydrocarbon (TPH) and polycyclic aromatic hydrocarbons (PAHs) present in crude oil contaminated sites are transferred to roots, shoots and finally the grains of rice crops (Oryza sativa L.) grown in those sites. Soil was artificially contaminated with crude oil at concentrations of 0, 1000, 5000, 10,000, and 15,000 mg/kg, followed by planting of rice seedlings. After harvest, TPH in plant samples were measured, and it was determined that the uptake of TPH by the plants gradually increased as the concentration of oil in soil increased. Further, from GC-MS analysis, it was observed that PAHs including naphthalene and phenanthrene bioaccumulated in rice plant parts. Vital physico-chemical properties of soil were also altered due to crude oil contamination. Our study revealed that rice plants grown in crude oil polluted sites can uptake TPH including PAHs, thus emphasising the importance of prior investigation of soil condition before cultivation of crops.

  16. Cooking with Fire: The Mutagenicity- and PAH-Emission Factors of Solid-Fuel Cookstoves

    Science.gov (United States)

    Emissions from solid fuels used for cooking cause ~4 million premature deaths per year. Advanced solid-fuel cookstoves are a potential solution, but they should be assessed by appropriate performance indicators, including biological effects. We evaluated two categories of solid...

  17. Supported manganese oxide on TiO{sub 2} for total oxidation of toluene and polycyclic aromatic hydrocarbons (PAHs): Characterization and catalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Aboukaïs, Antoine, E-mail: aboukais@univ-littoral.fr [Univ Lille Nord de France, 59000 Lille (France); Equipe Catalyse, UCEIV, EA 4492, MREI, ULCO, 59140 Dunkerque (France); Abi-Aad, Edmond [Univ Lille Nord de France, 59000 Lille (France); Equipe Catalyse, UCEIV, EA 4492, MREI, ULCO, 59140 Dunkerque (France); Taouk, Bechara [Laboratoire de Sécurité des procédés Chimiques (LSPC), EA 4704, INSA Rouen, Avenue de l' Université, 76801 Saint Etienne du Rouvray (France)

    2013-11-01

    Manganese oxide catalysts supported on titania (TiO{sub 2}) were prepared by incipient wetness impregnation method in order to elaborate catalysts for total oxidation of toluene and PAHs. These catalysts have been characterized by means of X-ray diffraction (XRD), electron paramagnetic resonance (EPR), temperature programmed reduction (TPR) and temperature programmed desorption (TPD). It has been shown that for the 5%Mn/TiO{sub 2} catalyst the reducibility and the mobility of oxygen are higher compared, in one side, to other x%Mn/TiO{sub 2} samples and, in another side, to catalysts where TiO{sub 2} support was replaced by γ-Al{sub 2}O{sub 3} or SiO{sub 2}. It has been shown that the content of manganese loading on TiO{sub 2} has an effect on the catalytic activity in the toluene oxidation. A maximum of activity was obtained for the 5%Mn/TiO{sub 2} catalyst where the total conversion of toluene was reached at 340 °C. This activity seems to be correlated to the presence of the Mn{sup 3+}/Mn{sup 4+} redox couple in the catalyst. When the Mn content increases, large particles of Mn{sub 2}O{sub 3} appear leading then to the decrease in the corresponding activity. In addition, compared to both other supports, TiO{sub 2} seems to be the best to give the best catalytic activity for the oxidation of toluene when it is loaded with 5% of manganese. For this reason, the latter catalyst was tested for the abatement of some PAHs. The light off temperature of PAHs compounds increases with increasing of benzene rings number and with decreasing of H/C ratio. All of PAHs are almost completely oxidized and converted at temperatures lower than 500 °C. - Highlights: • Preparation of x%MnO{sub 2}/TiO{sub 2} catalysts. • Catalytic oxidation tests of toluene and PAHs. • EPR, TPR and TPD characterizations of Mn(II) and Mn(IV) ions.

  18. Source characterization and exposure modeling of gas-phase polycyclic aromatic hydrocarbon (PAH) concentrations in Southern California

    Science.gov (United States)

    Masri, Shahir; Li, Lianfa; Dang, Andy; Chung, Judith H.; Chen, Jiu-Chiuan; Fan, Zhi-Hua (Tina); Wu, Jun

    2018-03-01

    Airborne exposures to polycyclic aromatic hydrocarbons (PAHs) are associated with adverse health outcomes. Because personal air measurements of PAHs are labor intensive and costly, spatial PAH exposure models are useful for epidemiological studies. However, few studies provide adequate spatial coverage to reflect intra-urban variability of ambient PAHs. In this study, we collected 39-40 weekly gas-phase PAH samples in southern California twice in summer and twice in winter, 2009, in order to characterize PAH source contributions and develop spatial models that can estimate gas-phase PAH concentrations at a high resolution. A spatial mixed regression model was constructed, including such variables as roadway, traffic, land-use, vegetation index, commercial cooking facilities, meteorology, and population density. Cross validation of the model resulted in an R2 of 0.66 for summer and 0.77 for winter. Results showed higher total PAH concentrations in winter. Pyrogenic sources, such as fossil fuels and diesel exhaust, were the most dominant contributors to total PAHs. PAH sources varied by season, with a higher fossil fuel and wood burning contribution in winter. Spatial autocorrelation accounted for a substantial amount of the variance in total PAH concentrations for both winter (56%) and summer (19%). In summer, other key variables explaining the variance included meteorological factors (9%), population density (15%), and roadway length (21%). In winter, the variance was also explained by traffic density (16%). In this study, source characterization confirmed the dominance of traffic and other fossil fuel sources to total measured gas-phase PAH concentrations while a spatial exposure model identified key predictors of PAH concentrations. Gas-phase PAH source characterization and exposure estimation is of high utility to epidemiologist and policy makers interested in understanding the health impacts of gas-phase PAHs and strategies to reduce emissions.

  19. Contamination levels, toxicity profiles, and emission sources of polycyclic aromatic hydrocarbons (PAHs) in the soils of an emerging industrial town and its environs in the Southeastern Nigeria.

    Science.gov (United States)

    Ofomatah, Anthony C; Okoye, Chukwuma O B

    2017-11-09

    Polycyclic aromatic hydrocarbon (PAH) concentrations in Nnewi and its environs were determined. Soil samples were extracted by sonication using hexane:dichloromethane (3:1) mixture and determined by gas chromatography-flame ionization detection. The total PAHs concentrations (μg/kg) were 16.681 to 46.815, being three orders of magnitude lower than the maximum permissible level recommended by the Agency for Toxic Substances and Disease Registry (ATSDR). These concentrations followed this order: industrial ˃ farmlands ˃ commercial ˃ residential. Industrialized areas showed higher concentrations (p ˂ 0.05) than the other areas. Diagnostic ratios show that the major source of PAHs was the open burning of industrial and agricultural wastes, as shown by the occurrence of highest concentrations in the industrial areas, followed by agricultural areas. Benzo[a]pyrene equivalent values showed non-pollution and very low toxicity. Nevertheless, it was clear that industrialization has had some impact on the PAHs levels in soils and the total environment in this area and could be problematic with time, except with proper environmental management.

  20. The C-C-C bending modes of PAHs : a new emission plateau from 15 to 20 mu m

    NARCIS (Netherlands)

    Van Kerckhoven, C; Hony, S; Peeters, E; Tielens, A. G. G. M.; Allamandola, LJ; Hudgins, DM; Cox, P; Roelfsema, PR; Voors, RHM; Waelkens, C; Waters, LBFM; Wesselius, PR

    We have obtained 2.5-45 mu m spectra of a sample of compact H II regions, YSOs and evolved stars in order to study the origin and evolution of interstellar Polycyclic Aromatic Hydrocarbon molecules (PAHs). Besides the well-known, strong PAH bands at 3.3, 6.2, 7.7, 8.6, and 11.2 mu m, these spectra

  1. Characteristics of PAHs from deep-frying and frying cooking fumes.

    Science.gov (United States)

    Yao, Zhiliang; Li, Jing; Wu, Bobo; Hao, Xuewei; Yin, Yong; Jiang, Xi

    2015-10-01

    Cooking fumes are an important indoor source of polycyclic aromatic hydrocarbons (PAHs). Because indoor pollution has a more substantial impact on human health than outdoor pollution, PAHs from cooking fumes have drawn considerable attention. In this study, 16 PAHs emitted through deep-frying and frying methods using rapeseed, soybean, peanut, and olive oil were examined under a laboratory fume hood. Controlled experiments were conducted to collect gas- and particulate-phase PAHs emitted from the cooking oil fumes, and PAH concentrations were quantified via high-performance liquid chromatography (HPLC). The results show that deep-frying methods generate more PAHs and benzo[a]pyrene (B[a]P) (1.3 and 10.9 times, respectively) because they consume greater volumes of edible oil and involve higher oil temperatures relative to those of frying methods. In addition, the total B[a]Peq concentration of deep-frying is 2.2-fold larger than that of frying. Regarding the four types of edible oils studied, rapeseed oil produced more PAH emission than the other three oil varieties. For all of the cooking tests, three- and four-ringed PAHs were the main PAH components regardless of the food and oil used. Concerning the PAH partition between gas and particulate phase, the gaseous compounds accounted for 59-96 % of the total. Meanwhile, the particulate fraction was richer of high molecular weight PAHs (five-six rings). Deep-frying and frying were confirmed as important sources of PAH pollution in internal environments. The results of this study provide additional insights into the polluting features of PAHs produced via cooking activities in indoor environments.

  2. Totally impermeable film (TIF reduces emissions in perennial crop fumigation

    Directory of Open Access Journals (Sweden)

    Suduan Gao

    2013-10-01

    Full Text Available Many perennial nursery fields and replanted orchards and vineyards in California are treated with preplant soil fumigants to control soilborne pests. In annual crops, such as strawberry, covering fumigated fields with totally impermeable film (TIF has shown promise in controlling emissions and improving fumigant distribution in soil. The objective of this research was to optimize the use of TIF for perennial crops via three field trials. TIF reduced peak emission flux and cumulative emissions by > 90% relative to polyethylene tarp during a 2-week covering period. After the TIF was cut, emissions were greatly reduced compared to when tarps were cut after 6 days. TIF maintained higher fumigant concentrations under tarp and in the soil than polyethylene film. The results indicate that TIF can increase fumigation efficiency for perennial crop growers.

  3. Persistent free radicals, heavy metals and PAHs generated in particulate soot emissions and residue ash from controlled combustion of common types of plastic

    International Nuclear Information System (INIS)

    Valavanidis, Athanasios; Iliopoulos, Nikiforos; Gotsis, George; Fiotakis, Konstantinos

    2008-01-01

    The production and use of polymeric materials worldwide has reached levels of 150 million tonnes per year, and the majority of plastic materials are discarded in waste landfills where are burned generating toxic emissions. In the present study we conducted laboratory experiments for batch combustion/burning of commercial polymeric materials, simulating conditions of open fire combustion, with the purpose to analyze their emissions for chemical characteristics of toxicological importance. We used common types of plastic materials: poly(vinyl chloride) (PVC), low and high density poly(ethylene) (LDPE, HDPE), poly(styrene) (PS), poly(propylene) (PP) and poly(ethylene terephthalate) (PET). Samples of particulate smoke (soot) collected on filters and residue solid ash produced by controlled burning conditions at 600-750 deg. C are used for analysis. Emissions of particulate matter, persistent free radicals embedded in the carbonaceous polymeric matrix, heavy metals, other elements and PAHs were determined in both types of samples. Results showed that all plastics burned easily generating charred residue solid ash and black airborne particulate smoke. Persistent carbon- and oxygen-centered radicals, known for their toxic effects in inhalable airborne particles, were detected in both particulate smoke emissions and residue solid ash. Concentrations of heavy metals and other elements (determined by Inductively Coupled Plasma Emission Spectrometry, ICP, method) were measured in the airborne soot and residue ash. Toxic heavy metals, such as Pb, Zn, Cr, Ni, and Cd were relatively at were found at low concentrations. High concentrations were found for some lithophilic elements, such as Na, Ca, Mg, Si and Al in particulate soot and residue solid ash. Measurements of PAHs showed that low molecular weight PAHs were at higher concentrations in the airborne particulate soot than in the residue solid ash for all types of plastic. Higher-ringed PAHs were detected at higher

  4. Persistent free radicals, heavy metals and PAHs generated in particulate soot emissions and residue ash from controlled combustion of common types of plastic.

    Science.gov (United States)

    Valavanidis, Athanasios; Iliopoulos, Nikiforos; Gotsis, George; Fiotakis, Konstantinos

    2008-08-15

    The production and use of polymeric materials worldwide has reached levels of 150 million tonnes per year, and the majority of plastic materials are discarded in waste landfills where are burned generating toxic emissions. In the present study we conducted laboratory experiments for batch combustion/burning of commercial polymeric materials, simulating conditions of open fire combustion, with the purpose to analyze their emissions for chemical characteristics of toxicological importance. We used common types of plastic materials: poly(vinyl chloride) (PVC), low and high density poly(ethylene) (LDPE, HDPE), poly(styrene) (PS), poly(propylene) (PP) and poly(ethylene terephthalate) (PET). Samples of particulate smoke (soot) collected on filters and residue solid ash produced by controlled burning conditions at 600-750 degrees C are used for analysis. Emissions of particulate matter, persistent free radicals embedded in the carbonaceous polymeric matrix, heavy metals, other elements and PAHs were determined in both types of samples. Results showed that all plastics burned easily generating charred residue solid ash and black airborne particulate smoke. Persistent carbon- and oxygen-centered radicals, known for their toxic effects in inhalable airborne particles, were detected in both particulate smoke emissions and residue solid ash. Concentrations of heavy metals and other elements (determined by Inductively Coupled Plasma Emission Spectrometry, ICP, method) were measured in the airborne soot and residue ash. Toxic heavy metals, such as Pb, Zn, Cr, Ni, and Cd were relatively at were found at low concentrations. High concentrations were found for some lithophilic elements, such as Na, Ca, Mg, Si and Al in particulate soot and residue solid ash. Measurements of PAHs showed that low molecular weight PAHs were at higher concentrations in the airborne particulate soot than in the residue solid ash for all types of plastic. Higher-ringed PAHs were detected at higher

  5. Dioxine and PAH-emissions from private incineration of wastes; Dioxin- und PAK-Emissionen der privaten Abfallverbrennung: Umwelt-Materialien Nr. 172 Luft

    Energy Technology Data Exchange (ETDEWEB)

    Nussbaumer, T.

    2004-07-01

    This report published by the Swiss Agency for the Environment, Forests and Landscape (SAEFL) presents the results of a literature study and situation analysis on the burning of wastes at the domestic level. The private burning of municipal solid waste, urban waste wood and other wastes as a potential source of toxic emissions and residues is discussed. Beside the heavy metals found in ash and flue gas, the paper looks at organic substances such as polycyclic aromatic hydrocarbons (PAH) and polychlorinated dibenzo-p-dioxines and polychlorinated dibenzofuranes (PCDD/F) that can be emitted in relevant concentrations. The aim of the study - to evaluate emission factors of PCDD/F and PAH from private waste incineration in wood stoves and boilers, in barrels, and in open fires - is discussed. A survey of recent investigations in Europe and the United States and the correlation between the most relevant emission factors is looked at. Critical situations leading to extremely high PCDD/F emissions are described.

  6. Origin and Distribution of PAHs in Ambient Particulate Samples at High Mountain Region in Southern China

    Directory of Open Access Journals (Sweden)

    Peng-hui Li

    2015-01-01

    Full Text Available To understand the deposition and transport of PAHs in southern China, a measurement campaign was conducted at a high-elevation site (the summit of Mount Heng, 1269 m A.S.L. from April 4 to May 31, 2009, and a total of 39 total suspended particulate samples were collected for measurement of PAH concentrations. The observed particulate-bound PAHs concentrations ranged from 1.63 to 29.83 ng/m3, with a mean concentration of 6.03 ng/m3. BbF, FLA, and PYR were the predominant compounds. Good correlations were found between individual PAHs and meteorological parameters such as atmospheric pressure, relative humidity, and ambient temperature. The backward trajectory analysis suggested that particulate samples measured at the Mount Heng region were predominantly associated with the air masses from southern China, while the air masses transported over northern and northwestern China had relative higher PAHs concentrations. Based on the diagnostic ratios and factor analysis, vehicular emission, coal combustion, industry emission, and unburned fossil fuels were suggested to be the PAHs sources at Mount Heng site. However, the reactivity and degradation of individual PAHs could influence the results of PAH source profiles, which deserves further investigations in the future.

  7. Emission Inventory for Fugitive Emissions in Denmark

    DEFF Research Database (Denmark)

    Plejdrup, Marlene Schmidt; Nielsen, Ole-Kenneth; Nielsen, Malene

    This report presents the methodology and data used in the Danish inventory of fugitive emissions from fuels for the years until 2007. The inventory of fugitive emissions includes CO2, CH4, N2O, NOx, CO, NMVOC, SO2, dioxin, PAH and particulate matter. In 2007 the total Danish emission of greenhouse...

  8. Atmospheric concentrations and air-soil gas exchange of polycyclic aromatic hydrocarbons (PAHs) in remote, rural village and urban areas of Beijing-Tianjin region, North China.

    Science.gov (United States)

    Wang, Wentao; Simonich, Staci; Giri, Basant; Chang, Ying; Zhang, Yuguang; Jia, Yuling; Tao, Shu; Wang, Rong; Wang, Bin; Li, Wei; Cao, Jun; Lu, Xiaoxia

    2011-07-01

    Forty passive air samplers were deployed to study the occurrence of gas and particulate phase PAHs in remote, rural village and urban areas of Beijing-Tianjin region, North China for four seasons (spring, summer, fall and winter) from 2007 to 2008. The influence of emissions on the spatial distribution pattern of air PAH concentrations was addressed. In addition, the air-soil gas exchange of PAHs was studied using fugacity calculations. The median gaseous and particulate phase PAH concentrations were 222 ng/m³ and 114 ng/m³, respectively, with a median total PAH concentration of 349 ng/m³. Higher PAH concentrations were measured in winter than in other seasons. Air PAH concentrations measured at the rural villages and urban sites in the northern mountain region were significantly lower than those measured at sites in the southern plain during all seasons. However, there was no significant difference in PAH concentrations between the rural villages and urban sites in the northern and southern areas. This urban-rural PAH distribution pattern was related to the location of PAH emission sources and the population distribution. The location of PAH emission sources explained 56%-77% of the spatial variation in ambient air PAH concentrations. The annual median air-soil gas exchange flux of PAHs was 42.2 ng/m²/day from soil to air. Among the 15 PAHs measured, acenaphthylene (ACY) and acenaphthene (ACE) contributed to more than half of the total exchange flux. Furthermore, the air-soil gas exchange fluxes of PAHs at the urban sites were higher than those at the remote and rural sites. In summer, more gaseous PAHs volatilized from soil to air because of higher temperatures and increased rainfall. However, in winter, more gaseous PAHs deposited from air to soil due to higher PAH emissions and lower temperatures. The soil TOC concentration had no significant influence on the air-soil gas exchange of PAHs. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. Atmospheric deposition of polycyclic aromatic hydrocarbons (PAHs) in Shanghai: the spatio-temporal variation and source identification

    Science.gov (United States)

    Cheng, Chen; Bi, Chunjuan; Wang, Dongqi; Yu, Zhongjie; Chen, Zhenlou

    2018-03-01

    This study investigated the dry and wet deposition fluxes of atmospheric polycyclic aromatic hydrocarbons (PAHs) in Shanghai, China. The flux sources were traced based on composition and spatio-temporal variation. The results show that wet deposition concentrations of PAHs ranged from 0.07 to 0.67 mg·L-1 and were correlated with temperature ( P<0.05). Dry deposition of PAHs concentrations ranged from 3.60-92.15 mg·L-1 and were higher in winter and spring than in summer and autumn. The annual PAH average fluxes were 0.631 mg·m-2·d-1 and 4.06 mg·m-2·d-1 for wet and dry deposition, respectively. The highest wet deposition of PAH fluxes was observed in summer, while dry deposition fluxes were higher in winter and spring. Atmospheric PAHs were deposited as dry deposition in spring and winter, yet wet deposition was the dominant pathway during summer. Total atmospheric PAH fluxes were higher in the northern areas than in the southern areas of Shanghai, and were also observed to be higher in winter and spring. Annual deposition of atmospheric PAHs was about 10.8 t in across all of Shanghai. Wet deposition of PAHs was primarily composed of two, three, or four rings, while dry deposition of PAHs was composed of four, five, or six rings. The atmospheric PAHs, composed of four, five, or six rings, primarily existed in the form of particulates. Coal combustion and vehicle emissions were the dominant sources of PAH in the observed area of downtown Shanghai. In suburban areas, industrial pollution, from sources such as coke oven, incinerator, and oil fired power plant, was as significant as vehicle emissions in contributing to the deposition of PAHs.

  10. Measurement as basis for emission reductions: VOC, PAH, PCB and dioxins in air in Ostrava. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Braathen, O.A.

    1996-12-31

    As part of the cooperation between Norway and the Czech Republic on environment protection, a project was carried out in Ostrava, Czech Republic, to transfer competence to Ostrava such that measurements of selected organic contaminants in air could be measured. The focus was on volatile organic compounds (VOC), polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PBC) and dioxin. This work also included acquiring and establishing equipment and analysis methodology. This is the final report from the project. 9 figs., 12 tabs.

  11. Polycyclic aromatic hydrocarbons (PAHs) concentration levels, pattern, source identification and soil toxicity assessment in urban traffic soil of Dhanbad, India.

    Science.gov (United States)

    Suman, Swapnil; Sinha, Alok; Tarafdar, Abhrajyoti

    2016-03-01

    Present study was carried out to assess and understand potential health risk and to examine the impact of vehicular traffic on the contamination status of urban traffic soils in Dhanbad City with respect to polycyclic aromatic hydrocarbons (PAHs). Eight urban traffic sites and two control/rural site surface soils were analyzed and the contents of 13 priority PAHs was determined. Total PAH concentration at traffic sites ranged from 1.019 μg g(-1) to 10.856 μg g(-1) with an average value of 3.488 μg g(-1). At control/rural site, average concentration of total PAHs was found to be 0.640 μg g(-1). PAH pattern was dominated by four- and five-ring PAHs (contributing >50% to the total PAHs) at all the eight traffic sites. On the other hand, rural soil showed a predominance of low molecular weight three-ring PAHs (contributing >30% to the total PAHs). Indeno[123-cd]pyrene/benz[ghi]perylene (IP/BgP) ratio indicated that PAH load at the traffic sites is predominated by the gasoline-driven vehicles. The ratio of Ant/(Ant+Phe) varied from 0.03 to 0.44, averaging 0.10; Fla/(Fla+Pyr) from 0.39 to 0.954, averaging 0.52; BaA/(BaA+Chry) from 0.156 to 0.60, averaging 0.44; and IP/(IP+BgP) from 0.176 to 0.811, averaging 0.286. The results indicated that vehicular emission was the major source for PAHs contamination with moderate effect of coal combustion and biomass combustion. Carcinogenic potency of PAH load in traffic soil was nearly 6.15 times higher as compared to the control/rural soil. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Source seasonality of polycyclic aromatic hydrocarbons (PAHs) in a subtropical city, Guangzhou, South China.

    Science.gov (United States)

    Li, J; Zhang, G; Li, X D; Qi, S H; Liu, G Q; Peng, X Z

    2006-02-15

    Mega-cities are large sources of air pollution on a regional base. Differences in energy structures, geographical settings and regional climate features lead to a large variety of air pollution sources from place to place. To understand the seasonality of air pollution sources is critical to precise emission inventories and a sound protection of human health. Based on a year-round dataset, the sources of PAHs in the air of Guangzhou were drawn by principal factor analysis (PCA) in combination with diagnostic ratios, and the seasonality of these sources were analyzed by PCA/MLR (multiple linear regressions) and discussed. The average total gaseous and particulate PAHs concentrations were 313 and 23.7 ng m(-3), respectively, with a higher concentration of vapor PAHs in summer and particulate PAHs in winter. In addition to vehicle exhaust, which contributed 69% of the particulate PAHs, coal combustion was still an important source and contributed 31% of the particulate PAHs. Relatively constant contribution from coal combustion was found through the year, implying that coal combustion in power plants was not a seasonally dependent source. Evaporation from contaminated ground may be an important source of light PAHs in summer, providing an average contribution of 68% to the total PAHs in this study. By comparing the PAH concentrations and meteorological parameters, we found that higher concentrations of particulate PAHs in winter resulted from enhanced vehicle exhaust under low temperature and accumulation of pollutants under decreased boundary layer, slower wind speed, and long-term dryness conditions. It is suggested that the typical subtropical monsoon climate in South China, cool and dry in winter, hot and humid in summer, may play a key role in controlling the source seasonality (by enhancing vehicle exhaust in winter, ground evaporation in summer), and hence the ambient concentrations of PAHs in the air.

  13. Distribution and Source Apportionment of Polycyclic Aromatic Hydrocarbons (PAHs) in Forest Soils from Urban to Rural Areas in the Pearl River Delta of Southern China

    Science.gov (United States)

    Xiao, Yihua; Tong, Fuchun; Kuang, Yuanwen; Chen, Bufeng

    2014-01-01

    The upper layer of forest soils (0–20 cm depth) were collected from urban, suburban, and rural areas in the Pearl River Delta of Southern China to estimate the distribution and the possible sources of polycyclic aromatic hydrocarbons (PAHs). Total concentrations of PAHs in the forest soils decreased significantly along the urban–suburban–rural gradient, indicating the influence of anthropogenic emissions on the PAH distribution in forest soils. High and low molecular weight PAHs dominated in the urban and rural forest soils, respectively, implying the difference in emission sources between the areas. The values of PAH isomeric diagnostic ratios indicated that forest soil PAHs were mainly originated from traffic emissions, mixed sources and coal/wood combustion in the urban, suburban and rural areas, respectively. Principal component analysis revealed that traffic emissions, coal burning and residential biomass combustion were the three primary contributors to forest soil PAHs in the Pearl River Delta. Long range transportation of PAHs via atmosphere from urban area might also impact the PAHs distribution in the forest soils of rural area. PMID:24599040

  14. Polycyclic aromatic hydrocarbons (PAHs) associated with PM2.5 within boundary layer: Cloud/fog and regional transport.

    Science.gov (United States)

    Yang, Minmin; Wang, Yan; Li, Hongli; Li, Tao; Nie, Xiaoling; Cao, Fangfang; Yang, Fengchun; Wang, Zhe; Wang, Tao; Qie, Guanghao; Jin, Tong; Du, Lili; Wang, Wenxing

    2018-06-15

    A study of PM 2.5 -associated PAHs analysis at Mount Lushan (1165m) was conducted to investigate the distributions of PAHs in PM 2.5 and influences of cloud/fog. The main purpose was to quantify the main emission sources of PAHs and estimate regional transport effects within the boundary layer. Mount Lushan is located between the boundary layer and troposphere, which is an ideal site for atmosphere transport investigation. The concentrations of PAHs in PM 2.5 were analyzed with GC-MS. The results showed that the volume concentration was 6.98ng/m 3 with a range from 1.47 to 25.17ng/m 3 and PAHs mass were 160.24μg/g (from 63.86 to 427.97μg/g) during the sampling time at Mount Lushan. The dominant compounds are BbF, Pyr and BP. In terms of aromatic-ring PAHs distributions, 4-6-ring PAHs are predominant, indicating that the high-ring PAHs tend to contribute more than low-ring PAHs in particulates. Due to frequent cloud/fog days at Mount Lushan, PAHs concentrations in the PM 2.5 were determined before and after cloud/fog weather. The results demonstrated that the cloud/fog and rain conditions cause lower PAHs levels. Regression analysis was used for studying the relationship of PAHs distributions with meteorological conditions like temperature, humidity and wind. The results showed that the temperature and wind speed were inversely related with PAHs concentration but humidity had no significant relationship. Furthermore, backward trajectories and PCA combined with DR (diagnostic ratio analysis) were employed to identify the influences of regional transport and main emission sources. The results revealed that PAHs in PM 2.5 were mainly affected by regional transport with the main emissions by mobile vehicle and steel industry, which contributed about 56.0% to the total PAHs in the area of Mount Lushan. In addition, backward trajectories revealed that the dominant air masses were from the northwest accounting for about one third of total PAHs. Copyright © 2018

  15. The characterisation of polycyclic aromatic hydrocarbons emissions from burning of different firewood species in Australia

    International Nuclear Information System (INIS)

    Zou, Linda Y.; Zhang Weidong; Atkiston, Steven

    2003-01-01

    Emission levels for PAHs varied with the type of wood burned. - Four kinds of woods used for residential heating in Australia were selected and burned under two burning conditions in a domestic wood heater installed in a laboratory. The selected wood species included pine (Pinus radiata), red gum (Eucalyptus camaldulensis), sugar gum (Eucalyptus cladocalyx) and yellow box (Eucalyptus melliodora). The two different burning conditions represented fast burning and slow burning, with the air inlet of the combustion chamber respectively 'full open' and 'half open'. By sampling and analysing particulate and gaseous emissions from the burning of each load of wood under defined experimental conditions, PAHs emissions and their profiles in the particulate and gaseous phases were obtained. 16 species out of the 18 selected PAHs were detected. Of these, seven species were detected in the gaseous phase and most were lower molecular weight compounds. Similarly, more than 10 species of PAHs were detected in the particulate phase and these were mostly heavier molecular weight compounds. Under both burning conditions, emission levels for total PAHs and total genotoxic PAHs were the highest for pine and lowest for sugar gum, with red gum being the second highest, followed by yellow box. Using the specific sampling method, gaseous PAHs accounted for above 90% mass fraction of total PAHs in comparison to particulate PAHs (10%). The majority of the genotoxic PAHs were present in the particulate phase. PAHs emission levels in slow burning conditions were generally higher than those in fast burning conditions

  16. PAH, BTEX, carbonyl compound, black-carbon, NO2 and ultrafine particle dynamometer bench emissions for Euro 4 and Euro 5 diesel and gasoline passenger cars

    Science.gov (United States)

    Louis, Cédric; Liu, Yao; Tassel, Patrick; Perret, Pascal; Chaumond, Agnès; André, Michel

    2016-09-01

    Although implementing Diesel particulate filters (DPF) and other novel aftertreatment technologies makes it possible to achieve significant reductions in particle mass emissions, it may induce the release of ultrafine particles and emissions of many other unregulated compounds. This paper focuses on (i) ultrafine particles, black carbon, BTEX, PAH, carbonyl compounds, and NO2 emissions from Euro 4 and Euro 5 Diesel and gasoline passenger cars, (ii) the influence of driving conditions (e.g., cold start, urban, rural and motorway conditions), and (iii) the impact of additive and catalysed DPF devices on vehicle emissions. Chassis dynamometer tests were conducted on four Euro 5 vehicles and two Euro 4 vehicles: gasoline vehicles with and without direct injection system and Diesel vehicles equipped with additive and catalysed particulate filters. The results showed that compared to hot-start cycles, cold-start urban cycles increased all pollutant emissions by a factor of two. The sole exception was NO2, which was reduced by a factor of 1.3-6. Particulate and black carbon emissions from the gasoline engines were significantly higher than those from the Diesel engines equipped with DPF. Moreover, the catalysed DPF emitted about 3-10 times more carbonyl compounds and particles than additive DPF, respectively, during urban driving cycles, while the additive DPF vehicles emitted 2 and 5 times more BTEX and carbonyl compounds during motorway driving cycles. Regarding particle number distribution, the motorway driving cycle induced the emission of particles smaller in diameter (mode at 15 nm) than the urban cold-start cycle (mode at 80-100 nm). The results showed a clear positive correlation between particle, black carbon, and BTEX emissions, and a negative correlation between particles and NO2.

  17. Optimization of heavy metals total emission, case study: Bor (Serbia)

    Science.gov (United States)

    Ilić, Ivana; Bogdanović, Dejan; Živković, Dragana; Milošević, Novica; Todorović, Boban

    2011-07-01

    The town of Bor (Serbia) is one of the most polluted towns in southeastern Europe. The copper smelter which is situated in the centre of the town is the main pollutant, mostly because of its old technology, which leads to environmental pollution caused by higher concentrations of SO 2 and PM 10. These facts show that the word is about a very polluted region in Europe which, apart from harming human health in the region itself, poses a particular danger for wider area of southeastern Europe. Optimization of heavy metal's total emission was undertaken because years of long contamination of the soil with heavy metals of anthropogenic origin created a danger that those heavy metals may enter the food chains of animals and people, which can lead to disastrous consequences. This work represents the usage of Geographic Information System (GIS) for establishing a multifactor assessment model to quantitatively divide polluted zones and for selecting control sites in a linear programming model, combined with PROMETHEE/GAIA method, Screen View modeling system, and linear programming model. The results show that emissions at some control sites need to be cut for about 40%. In order to control the background of heavy metal pollution in Bor, the ecological environment must be improved.

  18. Biomarkers of PAH exposure and hematologic effects in subjects exposed to combustion emission during residential (and professional) cooking practices in Pakistan.

    Science.gov (United States)

    Kamal, Atif; Cincinelli, Alessandra; Martellini, Tania; Malik, Riffat Naseem

    2016-01-01

    The aim of this study was to evaluate and compare the exposure of household women and professional male workers to combustion emission in the indoor and semi-outdoor environments, respectively, by using biochemical parameters and the biomarkers of exposure to polycyclic aromatic hydrocarbon (PAH). Female (WR n = 60) and male "cooks" (WC n = 60) exposed to the combustion emission of fuel wood and coal in rural/suburban areas of Pakistan were recruited in this study and compared to non-exposed female (CF) and male (CM) groups (n = 32 and 34, respectively). Urinary biomarkers of PAH exposure including 1-hyroxypyrene (1-OHPyr), α-naphthol, and β-naphthol were analyzed together with the biomarkers of effect, including the serum c-reactive proteins (CRP), white blood cells (WBCs), hemoglobin (Hb), red blood cells (RBC), and platelet (PLT) count. In addition, blood superoxide dismutase (SOD) and urinary level of 8-hydroxydeoxyguanosine (8-OHdG) were evaluated to determine the oxidative stress and DNA damage, respectively. A questionnaire was used to document demographic-, health-, and exposure-related information. The results showed that urinary β-naphthol was almost 44% higher in WR subjects than WC (median 7.69 vs. 3.39 μmol/mol-Cr, respectively; p = 0.01) and respective controls (CF). Higher urinary 8-OHdG were observed in WR (71.1 ng/mg-Cr) than WC (56.37 ng/mg-Cr) (p cooking (due to occupational requirement) than WR.

  19. Interstellar dehydrogenated PAH anions: vibrational spectra

    Science.gov (United States)

    Buragohain, Mridusmita; Pathak, Amit; Sarre, Peter; Gour, Nand Kishor

    2018-03-01

    Interstellar polycyclic aromatic hydrocarbon (PAH) molecules exist in diverse forms depending on the local physical environment. Formation of ionized PAHs (anions and cations) is favourable in the extreme conditions of the interstellar medium (ISM). Besides in their pure form, PAHs are also likely to exist in substituted forms; for example, PAHs with functional groups, dehydrogenated PAHs etc. A dehydrogenated PAH molecule might subsequently form fullerenes in the ISM as a result of ongoing chemical processes. This work presents a density functional theory (DFT) calculation on dehydrogenated PAH anions to explore the infrared emission spectra of these molecules and discuss any possible contribution towards observed IR features in the ISM. The results suggest that dehydrogenated PAH anions might be significantly contributing to the 3.3 μm region. Spectroscopic features unique to dehydrogenated PAH anions are highlighted that may be used for their possible identification in the ISM. A comparison has also been made to see the size effect on spectra of these PAHs.

  20. Polycyclic aromatic hydrocarbons (PAHs in the atmospheres of two French alpine valleys: sources and temporal patterns

    Directory of Open Access Journals (Sweden)

    N. Marchand

    2004-01-01

    Full Text Available Alpine valleys represent some of the most important crossroads for international heavy-duty traffic in Europe, but the full impact of this traffic on air quality is not known due to a lack of data concerning these complex systems. As part of the program "Pollution des Vallées Alpines" (POVA, we performed two sampling surveys of polycyclic aromatic hydrocarbons (PAHs in two sensitive valleys: the Chamonix and Maurienne Valleys, between France and Italy. Sampling campaigns were performed during the summer of 2000 and the winter of 2001, with both periods taking place during the closure of the "Tunnel du Mont-Blanc". The first objective of this paper is to describe the relations between PAH concentrations, external parameters (sampling site localization, meteorological parameters, sources, and aerosol characteristics, including its carbonaceous fraction (OC and EC. The second objective is to study the capacity of PAH profiles to accurately distinguish the different emission sources. Temporal evolution of the relative concentration of an individual PAH (CHR and the PAH groups BghiP+COR and BbF+BkF is studied in order to differentiate wood combustion, gasoline, and diesel emissions, respectively. The results show that the total particulate PAH concentrations were higher in the Chamonix valley during both seasons, despite the cessation of international traffic. Seasonal cycles, with higher concentrations in winter, are also stronger in this valley. During winter, particulate PAH concentration can reach very high levels (up to 155 ng.m-3 in this valley during cold anticyclonic periods. The examination of sources shows the impact during summer of heavy-duty traffic in the Maurienne valley and of gasoline vehicles in the Chamonix valley. During winter, Chamonix is characterized by the strong influence of wood combustion in residential fireplaces, even if the temporal evolution of specific PAH ratios are difficult to interpret. Information on sources

  1. Effects of hydrostatic pressure on the excitation-emission matrix (EEM) of a series of pure PAHs

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Zhi-juan [Ocean College, Zhejiang University of Technology, Hangzhou 310014 (China); Wang, Jie [College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014 (China); Ye, Shu-ming [College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou 310027 (China); Jiang, Chun-yue, E-mail: zjjcy@zjut.edu.cn [College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014 (China); Chen, Hang [College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou 310027 (China)

    2017-06-15

    The effects of hydrostatic pressure on the EEM of a series of pure PAHs (naphthalene, fluorene, phenanthrene, acenaphthene, fluoranthene, and anthracene) with three different concentrations (10{sup -6} mol L{sup -1}, 10{sup -5} mol L{sup -1}, and 10{sup -4} mol L{sup -1}) were investigated in a pressure range from 0.1 MPa to 60 MPa at room temperature. According to the EEM, 2 (naphthalene) to 12 (anthracene) fluorescence peaks were observed and the variation of EEM under high pressure were revealed by analyzing the fluorescence peaks positions and intensities with the increased hydrostatic pressure. It is found that fluorescence peak shifts were not detected in the compression, however, both the enhancement of intensity (e.g. naphthalene, 10{sup -6} mol L{sup -1}, peak of 225/330 nm, relative fluorescence intensity increased by 0.594) and reduction of intensity (e.g. fluorene, 10{sup -6} mol L{sup -1}, peak of 275/309 nm, relative fluorescence intensity decreased by 0.0966) were observed. Otherwise, the pressure effects were magnified when the concentration was increased (e.g. the relative fluorescence intensity of anthracene (peak of 380/425 nm) increased by 0.0165 (10{sup -6} mol L{sup -1}) and decreased by 0.479 (10{sup -6} mol L{sup -1}) when the pressure was elevated from 0.1 MPa to 60 MPa).

  2. Effects of hydrostatic pressure on the excitation-emission matrix (EEM) of a series of pure PAHs

    International Nuclear Information System (INIS)

    Sun, Zhi-juan; Wang, Jie; Ye, Shu-ming; Jiang, Chun-yue; Chen, Hang

    2017-01-01

    The effects of hydrostatic pressure on the EEM of a series of pure PAHs (naphthalene, fluorene, phenanthrene, acenaphthene, fluoranthene, and anthracene) with three different concentrations (10 -6 mol L -1 , 10 -5 mol L -1 , and 10 -4 mol L -1 ) were investigated in a pressure range from 0.1 MPa to 60 MPa at room temperature. According to the EEM, 2 (naphthalene) to 12 (anthracene) fluorescence peaks were observed and the variation of EEM under high pressure were revealed by analyzing the fluorescence peaks positions and intensities with the increased hydrostatic pressure. It is found that fluorescence peak shifts were not detected in the compression, however, both the enhancement of intensity (e.g. naphthalene, 10 -6 mol L -1 , peak of 225/330 nm, relative fluorescence intensity increased by 0.594) and reduction of intensity (e.g. fluorene, 10 -6 mol L -1 , peak of 275/309 nm, relative fluorescence intensity decreased by 0.0966) were observed. Otherwise, the pressure effects were magnified when the concentration was increased (e.g. the relative fluorescence intensity of anthracene (peak of 380/425 nm) increased by 0.0165 (10 -6 mol L -1 ) and decreased by 0.479 (10 -6 mol L -1 ) when the pressure was elevated from 0.1 MPa to 60 MPa).

  3. Impacts of urbanization on surface sediment quality: evidence from polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) contaminations in the Grand Canal of China.

    Science.gov (United States)

    Hong, Youwei; Yu, Shen; Yu, Guangbin; Liu, Yi; Li, Guilin; Wang, Min

    2012-06-01

    Organic pollutants, especially synthetic organic compounds, can indicate paces of anthropogenic activities. Effects of urbanization on polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) distributions in surface sediment were conducted in urban sections of the Grand Canal, China, consisting of a four-level urbanization gradient. The four-level urbanization gradients include three countryside towns, two small-size cities, three medium-size cities, and a large-size city. Diagnostic ratio analysis and factor analysis-multiple linear regression model were used for source apportionment of PAHs. Sediment quality guidelines (SQGs) of USA and Canada were employed to assess ecological risks of PAHs and PCBs in surface sediments of the Canal. Ranges of PAH and PCB concentrations in surface sediments were 0.66-22 mg/kg and 0.5-93 μg/kg, respectively. Coal-related sources were primary PAH sources and followed by vehicular emission. Total concentration, composition, and source apportionment of PAHs exhibited urbanization gradient effects. Total PCB concentrations increased with the urbanization gradient, while total PAHs concentration in surface sediments presented an inverted U Kuznets curve with the urbanization gradient. Elevated concentrations of both PAHs and PCBs ranged at effect range low levels or interim SQG, assessed by USA and Canadian SQGs. PAHs and PCBs in surface sediments of the Grand Canal showed urbanization gradient effects and low ecological risks.

  4. Source identification and ecological impact evaluation of PAHs in urban river sediments: A case study in Taiwan.

    Science.gov (United States)

    Tu, Y T; Ou, J H; Tsang, D C W; Dong, C D; Chen, C W; Kao, C M

    2018-03-01

    The Love River and Ho-Jin River, two major urban rivers in Kaohsiung City, Taiwan, are moderately to heavily polluted because different types of improperly treated wastewaters are discharged into the rivers. In this study, sediment and river water samples were collected from two rivers to investigate the river water quality and accumulation of polycyclic aromatic hydrocarbons (PAHs) in sediments. The spatial distribution, composition, and source appointment of PAHs of the sediments were examined. The impacts of PAHs on ecological system were assessed using toxic equivalence quotient (TEQ) of potentially carcinogenic PAHs (TEQ carc ) and sediment quality guidelines. The average PAHs concentrations ranged from 2161 ng/g in Love River sediment to 160 ng/g in Ho-Jin River sediment. This could be due to the fact that Love River Basin had much higher population density and pyrolytic activities. High-ring PAHs (4-6 rings) contributed to 59-90% of the total PAHs concentrations. Benzo(a)pyrene (BaP) had the highest toxic equivalence quotient (up to 188 ng TEQ/g). Moreover, the downstream sediments contained higher TEQ of total TPHs than midstream and upstream sediment samples. The PAHs were adsorbed onto the fine particles with high organic content. Results from diagnostic ratio analyses indicate that the PAHs in two urban river sediments might originate from oil/coal combustion, traffic-related emissions, and waste combustion (pyrogenic activities). Future pollution prevention and management should target the various industries, incinerators, and transportation emission in this region to reduce the PAHs pollution. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Total greenhouse gas emissions related to the Dutch crop production system

    NARCIS (Netherlands)

    Kramer, K.J.; Moll, H.C.; Nonhebel, S.

    1999-01-01

    This article discusses the greenhouse gas emissions (CO2, CH4, N2O) related to Dutch agricultural crop production. Emissions occur during agricultural processes (direct emissions) as well as in the life cycle of the required inputs (indirect emissions). An integrated approach assesses the total

  6. A whole farm model for quantifying total greenhouse gas emissions ...

    African Journals Online (AJOL)

    Valued Acer Customer

    2017-10-13

    Oct 13, 2017 ... In conclusion, the accounting methodologies that are described in this ... Corresponding author: riana@farmvision.co.za ... Studies to estimate the contribution of milk production to global GHG emissions do not reflect the.

  7. Total emissivity and spectral emissivity of high-temperature materials; Gesamtemissionsgrad und spektraler Emissionsgrad von Hochtemperaturmaterialien

    Energy Technology Data Exchange (ETDEWEB)

    Neuer, G.; Pohlmann, P.; Schreiber, E.

    1998-05-01

    A new emissivity measurement device with inductive sample heating is described. The disc shaped samples can be measured between 800 C and 2000 C in vacuum or in each available gas atmosphere. Two kinds of surface temperature measurement methods are described, one by measuring in a blackbody hole and one by measuring at the surface without additional measures to correct emissivity. Total normal and spectral emissivity at wavelengths between 0,5 {mu}m and 8,3 {mu}m of various high temperature materials like platinum and Pt-Rh-alloys, siliconcarbide and molybdenum disilicide have been measured. From the investigated materials a few have been selected as reference samples for comparative emissivity measurements fullfilling the requirement of stability on air up to 400 C to 1000 C in order to ensure reproducibility of the results at different measurement conditions in air and in vacuum. (orig.) [Deutsch] Der Aufbau einer neuen Messapparatur fuer Emissionsgradmessungen bei Temperaturen zwischen 1000 C und 2000 C wird beschrieben. Die scheibenfoermigen Proben werden induktiv beheizt, und die Messungen koennen entweder in Vakuum oder einer beliebigen Gasatmosphaere durchgefuehrt werden. Es werden zwei verschiedene Verfahren zur Bestimmung der Oberflaechentemperatur bechrieben, wobei entweder in einer oder direkt an der Oberflaeche ohne zusaetzliche Massnahmen zur Emissionsgradkorrektur gemessen wird. An verschiedenen Hochtemperaturwerkstoffen wie Platin und Platin-Rhodium-Legierungen, Siliziumkarbid mit unterschiedlichen Herstellungsarten und Molybdaen-Disilizid wurden der Gesamtemissionsgrad und der spektrale Emissionsgrad bei Wellenlaengen von 0,5 {mu}m bis 8,3 {mu}m senkrecht zur Oberflaeche gemessen. Aus den untersuchten Materialien wurden solche als Referenzmaterialien fuer vergleichende Emissionsgradmessungen ausgewaehlt, die sowohl im Vakuum als auch in Luft und bei Temperaturen von 1400 C bis 1600 C unter verschiedenen Messbedingungen reproduzierbare Ergebnisse

  8. An Emission Inventory of Polycyclic Aromatic Hydrocarbons in China

    Science.gov (United States)

    Mu, Xilong; Zhu, Xianlei; Wang, Xuesong

    2015-04-01

    Polycyclic Aromatic Hydrocarbons (PAHs) are among the most dangerous compounds due to their high carcinogenic and mutagenic character. Emission inventory provides the primary data to account for the sources of ambient PAHs and server as a necessary database for effective PAHs pollution control. China is experiencing fast economic growth and large energy consumption, which might result in a large amount of PAHs anthropogenic emissions. Therefore, based on the previous studies and combined recently field emission measurements as well as socio-economic activity data, the development of a nationwide PAHs emission inventory is needed. In this work, the emission inventory of 16 PAHs listed as U.S. Environmental Protection Agency priority pollutants in China in the year 2012 is compiled. The emission amounts of PAHs were estimated as annual rates of emission-related activities multiplied by respective emission factors. The activities such as fuel consumption, including fossil fuel and biofuel, and socio-economic statistics were obtained from yearbook released by Chinese central government and/or provincial governments, as well as related industry reports. Emission factors were derived from the related literature. Recently reported emission factors from local measurements were used. The total emissions of PAHs were 120611 ton in 2012. In China, PAHs were emitted predominantly from domestic combustion of coal and biofuel, coking industry and motor vehicles, accounting for 72% of the total amount. PAHs emission profiles were significantly different between China and the other countries. The emission profile in China featured a relatively higher portion of high molecular weight species with carcinogenic potential due to large contributions of domestic combustion and coking industry. Domestic combustion of straw, coal and firewood emitted 19464 ton, 8831 ton, and 5062 ton of PAHs, respectively, which were much higher than those in other countries. Emission per capita showed

  9. The characterisation of polycyclic aromatic hydrocarbons emissions from burning of different firewood species in Australia.

    Science.gov (United States)

    Zou, Linda Y; Zhang, Weidong; Atkiston, Steven

    2003-01-01

    Four kinds of woods used for residential heating in Australia were selected and burned under two burning conditions in a domestic wood heater installed in a laboratory. The selected wood species included pine (Pinus radiata), red gum (Eucalvptus camaldulensis), sugar gum (Eucalyptus cladocalyx) and yellow box (Eucalyptus melliodora). The two different burning conditions represented fast burning and slow burning, with the air inlet of the combustion chamber respectively 'full open' and 'half open'. By sampling and analysing particulate and gaseous emissions from the burning of each load of wood under defined experimental conditions, PAHs emissions and their profiles in the particulate and gaseous phases were obtained. 16 species out of the 18 selected PAHs were detected. Of these, seven species were detected in the gaseous phase and most were lower molecular weight compounds.Similarly, more than 10 species of PAHs were detected in the particulate phase and these were mostly heavier molecular weight compounds. Under both burning conditions, emission levels for total PAHs and total genotoxic PAHs were the highest for pine and lowest for sugar gum, with red gum being the second highest, followed by yellow box. Using the specific sampling method, gaseous PAHs accounted for above 90% mass fraction of total PAHs in comparison to particulate PAHs (10%). The majority of the genotoxic PAHs were present in the particulate phase. PAHs emission levels in slow burning conditions were generally higher than those in fast burning conditions.

  10. Structure-reactivity correlation of diesel soot and characterization of polycyclic aromatic hydrocarbons and carbonyls in biofuel emissions; Struktur-Reaktivitaets-Korrelation von Dieselruss und Charakterisierung von PAHs und Carbonylen im Abgas von Biokraftstoffen

    Energy Technology Data Exchange (ETDEWEB)

    Knauer, Markus

    2010-12-29

    This work reports on the determination of the structure-reactivity correlation of soot using Raman microscopy (RM) and temperature programmed oxidation (TPO), as well as on changes in the emission level of polycyclic aromatic hydrocarbons (PAH) and carbonyls at the combustion of biofuels. To characterize the reactivity of soot the combustion behaviour of model- and diesel soot has been determined by means of TPO in the presence of oxygen. In this context, spark-discharge soot and graphite powder were applied as model substances, and EURO VI and IV diesel soot as real-diesel soots. The structure of soot samples was investigated by RM and structural changes during the TPO were observed. In order to make a statement about the changes in PAH and carbonyl compound emissions during combustion of biofuels, samples were taken at different engine testbenches. Fossil fuel, biodiesel and vegetable oil were used during this study, as well as fuel mixtures with different biofuel fractions.

  11. Structure-reactivity correlation of diesel soot and characterization of polycyclic aromatic hydrocarbons and carbonyls in biofuel emissions; Struktur-Reaktivitaets-Korrelation von Dieselruss und Charakterisierung von PAHs und Carbonylen im Abgas von Biokraftstoffen

    Energy Technology Data Exchange (ETDEWEB)

    Knauer, Markus

    2009-12-29

    This work reports on the determination of the structure-reactivity correlation of soot using Raman microscopy (RM) and temperature programmed oxidation (TPO), as well as on changes in the emission level of polycyclic aromatic hydrocarbons (PAH) and carbonyls at the combustion of biofuels. To characterize the reactivity of soot the combustion behaviour of model- and diesel soot has been determined by means of TPO in the presence of oxygen. In this context, spark-discharge soot and graphite powder were applied as model substances, and EURO VI and IV diesel soot as real-diesel soots. The structure of soot samples was investigated by RM and structural changes during the TPO were observed. In order to make a statement about the changes in PAH and carbonyl compound emissions during combustion of biofuels, samples were taken at different engine testbenches. Fossil fuel, biodiesel and vegetable oil were used during this study, as well as fuel mixtures with different biofuel fractions.

  12. Summertime PAH assembly in Mediterranean air: the Herceg Novi sampling station as an example

    Directory of Open Access Journals (Sweden)

    VLADIMIR Z. JOVANOVIC

    2007-02-01

    Full Text Available The results of an analysis of the total suspended particles (TSP, total solvent organic extracts (TSOE, and polycyclic aromatic hydrocarbons (PAHs in aerosol samples collected from the atmosphere of Herceg Novi from 17th June to 15th September in 1998 and 1999 are presented. The TSP and TSOE concentrations were determined by the standard gravimetric method, whereas the PAHs from the organic part of the aerosol were analysed by the GC-MS method. The difference found in the TSP and TSOE contents between the two consecutive years (before and after the bombing of Yugoslavia was attributed to changes in the intensity and origin of emissions from dominant sources, specific to the summer period of this region. The content and nature of the PAHs identified in the samples of 1998 and 1999 were also different, indicating the significance of traffic as the source of PAHs, which was of significantly lower intensity in 1999 (immediately after the war due to the lower influx of tourists. Factor analysis showed that the PAH distribution at the measuring site in 1999 was largely determined by meteorological parameters, mainly by the average daily temperature and wind direction. In 1998, the dominant impact on the PAH distribution was attributed to traffic, both local and from a wider region, without an explicit impact of meteorological parameters.

  13. Ecotoxicological and Health Risk Assessment of Polycyclic Aromatic Hydrocarbons (PAHs) in Short-Neck Clam (Paphia undulata) and Contaminated Sediments in Malacca Strait, Malaysia.

    Science.gov (United States)

    Keshavarzifard, Mehrzad; Zakaria, Mohamad Pauzi; Sharifi, Reza

    2017-10-01

    The distribution, sources, and human health risk assessment of polycyclic aromatic hydrocarbons (PAHs) in surface sediment and the edible tissue of short-neck clam (Paphia undulata) from mudflat ecosystem in the west coast of Malaysia were investigated. The concentrations of ∑ 16 PAHs varied from 347.05 to 6207.5 and 179.32 to 1657.5 ng g -1 in sediment and short-neck clam samples, respectively. The calculations of mean PEL quotients (mean-PELQs) showed that the ecological risk of PAHs in the sediment samples was low to moderate-high level, whereas the total health risk through ingestion and dermal contact was considerably high. The PAHs biota sediment accumulation factors data for short-neck clam were obtained in this study, indicating a preferential accumulation of lower molecular weight PAHs. The source apportionment of PAHs in sediment using positive matrix factorization model indicated that the highest contribution to the PAHs was from diesel emissions (30.38%) followed by oil and oil derivate and incomplete coal combustion (23.06%), vehicular emissions (16.43%), wood combustion (15.93%), and natural gas combustion (14.2%). A preliminary evaluation of human health risk using chronic daily intake, hazard index, benzo[a]pyrene-equivalent (BaP eq ) concentration, and the incremental lifetime cancer risk indicated that PAHs in short-neck clam would induce potential carcinogenic effects in the consumers.

  14. THE INFRARED SPECTRA OF VERY LARGE IRREGULAR POLYCYCLIC AROMATIC HYDROCARBONS (PAHs): OBSERVATIONAL PROBES OF ASTRONOMICAL PAH GEOMETRY, SIZE, AND CHARGE

    International Nuclear Information System (INIS)

    Bauschlicher, Charles W.; Peeters, Els; Allamandola, Louis J.

    2009-01-01

    The mid-infrared (IR) spectra of six large, irregular polycyclic aromatic hydrocarbons (PAHs) with formulae (C 84 H 24 -C 120 H 36 ) have been computed using density functional theory (DFT). Trends in the dominant band positions and intensities are compared to those of large, compact PAHs as a function of geometry, size, and charge. Irregular edge moieties that are common in terrestrial PAHs, such as bay regions and rings with quartet hydrogens, are shown to be uncommon in astronomical PAHs. As for all PAHs comprised solely of C and H reported to date, mid-IR emission from irregular PAHs fails to produce a strong CC str band at 6.2 μm, the position characteristic of the important, class A astronomical PAH spectra. Earlier studies showed that inclusion of nitrogen within a PAH shifts this to 6.2 μm for PAH cations. Here we show that this band shifts to 6.3 μm in nitrogenated PAH anions, close to the position of the CC stretch in class B astronomical PAH spectra. Thus, nitrogenated PAHs may be important in all sources and the peak position of the CC stretch near 6.2 μm appears to directly reflect the PAH cation to anion ratio. Large irregular PAHs exhibit features at 7.8 μm but lack them near 8.6 μm. Hence, the 7.7 μm astronomical feature is produced by a mixture of small and large PAHs while the 8.6 μm band can only be produced by large compact PAHs. As with the CC str , the position and profile of these bands reflect the PAH cation to anion ratio.

  15. Phenylacetylene and PAH

    Indian Academy of Sciences (India)

    During the last decades, polycyclic aromatic hydrocarbons (PAHs) and other related aromatic compounds, such as ionized PAHs, have received considerable attention from astronomers, astrobiologists, environmentalists, and the combustion community. In the interstellar medium, PAH like species account for up to 10% of ...

  16. Comparative study of radiometric and calorimetric methods for total hemispherical emissivity measurements

    Science.gov (United States)

    Monchau, Jean-Pierre; Hameury, Jacques; Ausset, Patrick; Hay, Bruno; Ibos, Laurent; Candau, Yves

    2018-05-01

    Accurate knowledge of infrared emissivity is important in applications such as surface temperature measurements by infrared thermography or thermal balance for building walls. A comparison of total hemispherical emissivity measurement was performed by two laboratories: the Laboratoire National de Métrologie et d'Essais (LNE) and the Centre d'Études et de Recherche en Thermique, Environnement et Systèmes (CERTES). Both laboratories performed emissivity measurements on four samples, chosen to cover a large range of emissivity values and angular reflectance behaviors. The samples were polished aluminum (highly specular, low emissivity), bulk PVC (slightly specular, high emissivity), sandblasted aluminum (diffuse surface, medium emissivity), and aluminum paint (slightly specular surface, medium emissivity). Results obtained using five measurement techniques were compared. LNE used a calorimetric method for direct total hemispherical emissivity measurement [1], an absolute reflectometric measurement method [2], and a relative reflectometric measurement method. CERTES used two total hemispherical directional reflectometric measurement methods [3, 4]. For indirect techniques by reflectance measurements, the total hemispherical emissivity values were calculated from directional hemispherical reflectance measurement results using spectral integration when required and directional to hemispherical extrapolation. Results were compared, taking into account measurement uncertainties; an added uncertainty was introduced to account for heterogeneity over the surfaces of the samples and between samples. All techniques gave large relative uncertainties for a low emissive and very specular material (polished aluminum), and results were quite scattered. All the indirect techniques by reflectance measurement gave results within ±0.01 for a high emissivity material. A commercial aluminum paint appears to be a good candidate for producing samples with medium level of emissivity

  17. Occupational PAH Exposures during Prescribed Pile Burns

    Science.gov (United States)

    Robinson, M. S.; Anthony, T. R.; Littau, S. R.; Herckes, P.; Nelson, X.; Poplin, G. S.; Burgess, J. L.

    2008-01-01

    Wildland firefighters are exposed to particulate matter and gases containing polycyclic aromatic hydrocarbons (PAHs), many of which are known carcinogens. Our objective was to evaluate the extent of firefighter exposure to particulate and PAHs during prescribed pile burns of mainly ponderosa pine slash and determine whether these exposures were correlated with changes in urinary 1-hydroxypyrene (1-HP), a PAH metabolite. Personal and area sampling for particulate and PAH exposures were conducted on the White Mountain Apache Tribe reservation, working with 21 Bureau of Indian Affairs/Fort Apache Agency wildland firefighters during the fall of 2006. Urine samples were collected pre- and post-exposure and pulmonary function was measured. Personal PAH exposures were detectable for only 3 of 16 PAHs analyzed: naphthalene, phenanthrene, and fluorene, all of which were identified only in vapor-phase samples. Condensed-phase PAHs were detected in PM2.5 area samples (20 of 21 PAHs analyzed were detected, all but naphthalene) at concentrations below 1 μg m−3. The total PAH/PM2.5 mass fractions were roughly a factor of two higher during smoldering (1.06 ± 0.15) than ignition (0.55 ± 0.04 μg mg−1). There were no significant changes in urinary 1-HP or pulmonary function following exposure to pile burning. In summary, PAH exposures were low in pile burns, and urinary testing for a PAH metabolite failed to show a significant difference between baseline and post-exposure measurements. PMID:18515848

  18. Effect of biomass open burning on particulate matter and polycyclic aromatic hydrocarbon concentration levels and PAH dry deposition in ambient air.

    Science.gov (United States)

    Chiu, Jui C; Shen, Yun H; Li, Hsing W; Chang, Shun S; Wang, Lin C; Chang-Chien, Guo P

    2011-01-01

    The objectives of the present study were to investigate particulate matter (PM) and polycyclic aromatic hydrocarbon (PAH) concentrations in ambient air during rice straw open burning and non-open burning periods. In the ambient air of a rice field, the mean PM concentration during and after an open burning event were 1828 and 102 μg m⁻³, respectively, which demonstrates that during a rice field open burning event, the PM concentration in the ambient air of rice field is over 17 times higher than that of the non-open burning period. During an open burning event, the mean total PAH and total toxic equivalence (BaP(eq)) concentrations in the ambient air of a rice field were 7206 ng m⁻³ and 10.3 ng m⁻³, respectively, whereas after the open burning event, they were 376 ng m⁻³ and 1.50 ng m⁻³, respectively. Open burning thus increases total PAH and total BaP(eq) concentrations by 19-fold and 6.8-fold, respectively. During a rice straw open burning event, in the ambient air of a rice field, the mean dry deposition fluxes of total PAHs and total BaP(eq) were 1222 μg m⁻² day⁻¹ and 4.80 μg m⁻² day⁻¹, respectively, which are approximately 60- and 3-fold higher than those during the non-open burning period, respectively. During the non-open burning period, particle-bound PAHs contributed 79.2-84.2% of total dry deposition fluxes (gas + particle) of total PAHs. However, an open burning event increases the contribution to total PAH dry deposition by particle-bound PAHs by up to 85.9-95.5%. The results show that due to the increased amount of PM in the ambient air resulting from rice straw open burning, particle-bound PAHs contributed more to dry deposition fluxes of total PAHs than they do during non-open burning periods. The results show that biomass (rice straw) open burning is an important PAH emission source that significantly increases both PM and PAH concentration levels and PAH dry deposition in ambient air.

  19. The hydrogen coverage of interstellar PAHs [Polycyclic Aromatic Hydrocarbons

    International Nuclear Information System (INIS)

    Tielens, A.G.G.M.; Allamandola, L.J.; Barker, J.R.; Cohen, M.

    1986-02-01

    The rate at which the CH bond in interstellar Polycyclic Aromatic Hydrocarbons (PAHs) rupture due to the absorption of a uv photon has been calculated. The results show that small PAHs (less than or equal to 25 carbon atoms) are expected to be partially dehydrogenated in regions with intense uv fields, while large PAHs (greater than or equal to 25 atoms) are expected to be completely hydrogenated in those regions. Because estimate of the carbon content of interstellar PAHs lie in the range of 20 to 25 carbon atoms, dehydrogenation is probably not very important. Because of the absence of other emission features besides the 11.3 micrometer feature in ground-based 8 to 13 micrometer spectra, it has been suggested that interstellar PAHs are partially dehydrogenated. However, IRAS 8 to 22 micrometer spectra of most sources that show strong 7.7 and 11.2 micrometer emission features also show a plateau of emission extending from about 11.3 to 14 micrometer. Like the 11.3 micrometer feature, this new feature is attributed to the CH out of plane bending mode in PAHs. This new feature shows that interstellar PAHs are not as dehydrogenated as estimated from ground-based 8 to 13 micrometer spectra. It also constrains the molecular structure of interstellar PAHs. In particular, it seems that very condensed PAHs, such as coronene and circumcoronene, dominate the interstellar PAH mixture as expected from stability arguments

  20. Nature and sources of particle associated polycyclic aromatic hydrocarbons (PAH) in the atmospheric environment of an urban area

    International Nuclear Information System (INIS)

    Callén, M.S.; López, J.M.; Iturmendi, A.; Mastral, A.M.

    2013-01-01

    The total PAH associated to the airborne particulate matter (PM10) was apportioned by one receptor model based on positive matrix factorization (PMF) in an urban environment (Zaragoza city, Spain) during February 2010–January 2011. Four sources associated with coal combustion, gasoline, vehicular and stationary emissions were identified, allowing a good modelling of the total PAH (R 2 = 0.99). A seasonal behaviour of the four factors was obtained with higher concentrations in the cold season. The NE direction was one of the predominant directions showing the negative impact of industrial parks, a paper factory and a highway located in that direction. Samples were classified according to hierarchical cluster analysis obtaining that, episodes with the most negative impact on human health (the highest lifetime cancer risk concentrations), were produced by a higher contribution of stationary and vehicular emissions in winter season favoured by high relative humidity, low temperature and low wind speed. -- Highlights: ► PMF receptor model apportioned four sources associated to the total PAH in Zaragoza. ► The sources were: vehicular, coal combustion, gasoline and stationary emissions. ► Samples were additionally classified according to hierarchical cluster analysis. ► The stationary and vehicular emissions factors showed higher risk for human health. ► Low temperature, wind speed and high relative humidity favoured this negative impact. -- Episodes with the most negative impact on human health regarding PAH were produced by a higher contribution of stationary and vehicular emissions in winter season

  1. PAHs levels in gas and particle-bound phase in schools at different locations in Serbia

    Directory of Open Access Journals (Sweden)

    Živković Marija

    2015-01-01

    Full Text Available This study investigated seasonal variation of PAHs and their partition between gas and particulate-bounded phases in indoor and outdoor air in 4 schools in Serbia located at different locations. The sampling campaigns were conducted during one workweek at each school successively. Campaigns were conducted in schools during heating and non-heating seasons in December 2011 and June 2012. Seasonal variations of gas and particle-bounded PAHs concentrations were observed with higher levels during heating season. The highest total PAH values were associated with the gas phase in both sampling periods. The total PAHs concentration at indoor and at the outdoor sites, during heating season, ranged from 88.45 to 447.72 ng/m3 and 201.69 to 1017.15 ng/m3, respectively. During non-heating season, the total PAHs concentration ranged from 36.91 to 271.57 ng/m3 in indoor environment and 27.00 to 132.32 ng/m3 in outdoor environment. Most of the I/O ratios were less than 1, which indicated that the indoor PAHs were mostly from outdoor sources. The use of diagnostic ratio showed that traffic emission and coal combustion are the major sources of PAHs. Only the diagnostic ratios for the school, located near the industrial area, showed significant deviation compared to other schools. [Projekat Ministarstva nauke Republike Srbije, br. TR33036: Development of new meteorological mast for turbulence parameters characterization and br. III42008: Evaluation of Energy Performances and Indoor Environment Quality of Educational Buildings in Serbia with Impact to Health

  2. Source apportionment of the particulate PAHs at Seoul, Korea: impact of long range transport to a megacity

    Directory of Open Access Journals (Sweden)

    J. Y. Lee

    2007-07-01

    Full Text Available Northeast Asia including China, Korea, and Japan is one of the world's largest fossil fuel consumption regions. Seoul, Korea, is a megacity in Northeast Asia. Its emissions of air pollutants can affect the region, and in turn it is also affected by regional emissions. To understand the extent of these influences, major sources of ambient particulate PAHs in Seoul were identified and quantified based on measurements made between August 2002 and December 2003. The chemical mass balance (CMB model was applied. Seven major emission sources were identified based on the emission data in Seoul and Northeast Asia: Gasoline and diesel vehicles, residential coal use, coke ovens, coal power plants, biomass burning, and natural gas (NG combustion. The major sources of particulate PAHs in Seoul during the whole measurement period were gasoline and diesel vehicles, together accounted for 31% of the measured particulate PAHs levels. However, the source contributions showed distinct daily and seasonal variations. High contributions of biomass burning and coal (residential and coke oven were observed in fall and winter, accounting for 63% and 82% of the total concentration of PAHs, respectively. Since these sources were not strong in and around Seoul, they are likely to be related to transport from outside of Seoul, from China and/or North Korea. This implies that the air quality in a mega-city such as Seoul can be influenced by the long range transport of air pollutants such as PAHs.

  3. PAH Spectroscopy: Past, Present and Future

    Science.gov (United States)

    Mattioda, Andrew

    2016-01-01

    Since their discovery in the 1970's, astronomers, astrophysicists and astrochemists have been intrigued by the nearly ubiquitous unidentified infrared emission (UIR) bands. In the 1980's, investigators determined the most probably source of these emissions was a family of molecules known as Polycyclic Aromatic Hydrocarbons or simply PAHs. In order to better understand these interstellar IR features and utilize them as chemical probes of the cosmos, laboratory spectroscopists have spent the last three decades investigating the spectroscopy of PAHs under astrophysically relevant conditions. This presentation will discuss the similarities and differences in the spectroscopic properties of PAHs as one goes from the Far to Mid to Near infrared wavelength regions and probe the changes observed in PAH spectra as they go from neutral to ionized molecules suspended in an inert gas matrix, to PAHs in a water ice matrix and as a thin film. In selected instances, the experimental results will be compared to theoretical values. The presentation will conclude with a discussion on the future directions of PAH spectroscopy.

  4. Quantification of variability and uncertainty in lawn and garden equipment NOx and total hydrocarbon emission factors.

    Science.gov (United States)

    Frey, H Christopher; Bammi, Sachin

    2002-04-01

    Variability refers to real differences in emissions among multiple emission sources at any given time or over time for any individual emission source. Variability in emissions can be attributed to variation in fuel or feedstock composition, ambient temperature, design, maintenance, or operation. Uncertainty refers to lack of knowledge regarding the true value of emissions. Sources of uncertainty include small sample sizes, bias or imprecision in measurements, nonrepresentativeness, or lack of data. Quantitative methods for characterizing both variability and uncertainty are demonstrated and applied to case studies of emission factors for lawn and garden (L&G) equipment engines. Variability was quantified using empirical and parametric distributions. Bootstrap simulation was used to characterize confidence intervals for the fitted distributions. The 95% confidence intervals for the mean grams per brake horsepower/hour (g/hp-hr) emission factors for two-stroke engine total hydrocarbon (THC) and NOx emissions were from -30 to +41% and from -45 to +75%, respectively. The confidence intervals for four-stroke engines were from -33 to +46% for THCs and from -27 to +35% for NOx. These quantitative measures of uncertainty convey information regarding the quality of the emission factors and serve as a basis for calculation of uncertainty in emission inventories (EIs).

  5. Chemometric techniques in distribution, characterisation and source apportionment of polycyclic aromatic hydrocarbons (PAHS) in aquaculture sediments in Malaysia.

    Science.gov (United States)

    Retnam, Ananthy; Zakaria, Mohamad Pauzi; Juahir, Hafizan; Aris, Ahmad Zaharin; Zali, Munirah Abdul; Kasim, Mohd Fadhil

    2013-04-15

    This study investigated polycyclic aromatic hydrocarbons (PAHs) pollution in surface sediments within aquaculture areas in Peninsular Malaysia using chemometric techniques, forensics and univariate methods. The samples were analysed using soxhlet extraction, silica gel column clean-up and gas chromatography mass spectrometry. The total PAH concentrations ranged from 20 to 1841 ng/g with a mean of 363 ng/g dw. The application of chemometric techniques enabled clustering and discrimination of the aquaculture sediments into four groups according to the contamination levels. A combination of chemometric and molecular indices was used to identify the sources of PAHs, which could be attributed to vehicle emissions, oil combustion and biomass combustion. Source apportionment using absolute principle component scores-multiple linear regression showed that the main sources of PAHs are vehicle emissions 54%, oil 37% and biomass combustion 9%. Land-based pollution from vehicle emissions is the predominant contributor of PAHs in the aquaculture sediments of Peninsular Malaysia. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. THE CHARGE STATE OF POLYCYCLIC AROMATIC HYDROCARBONS ACROSS REFLECTION NEBULAE: PAH CHARGE BALANCE AND CALIBRATION

    International Nuclear Information System (INIS)

    Boersma, C.; Bregman, J.; Allamandola, L. J.

    2016-01-01

    Low-resolution Spitzer spectral map data (>1700 spectra) of ten reflection nebulae (RNe) fields are analyzed using the data and tools available through the NASA Ames PAH IR Spectroscopic Database. The PAH emission is broken down into PAH charge state using a database fitting approach. Here, the physics of the PAH emission process is taken into account and uses target appropriate parameters, e.g., a stellar radiation model for the exciting star. The breakdown results are combined with results derived using the traditional PAH band strength approach, which interprets particular PAH band strength ratios as proxies for the PAH charge state, e.g., the 6.2/11.2 μ m PAH band strength ratio. These are successfully calibrated against their database equivalent; the PAH ionized fraction ( f i ). The PAH ionized fraction is converted into the PAH ionization parameter, which relates the PAH ionized fraction to the strength of the radiation field, gas temperature and electron density. The behavior of the 12.7 μ m PAH band is evaluated as a tracer for PAH ionization and erosion. The plot of the 8.6 versus 11.2 μ m PAH band strength for the northwest photo-dominated region (PDR) in NGC 7023 is shown to be a robust diagnostic template for the PAH ionized fraction. Remarkably, most of the other RNe fall within the limits set by NGC 7023. Finally, PAH spectroscopic templates are constructed and verified as principal components. Template spectra derived from NGC 7023 and NGC 2023 compare extremely well with each other, with those derived for NGC 7023 successfully reproducing the PAH emission observed from NGC 2023.

  7. THE CHARGE STATE OF POLYCYCLIC AROMATIC HYDROCARBONS ACROSS REFLECTION NEBULAE: PAH CHARGE BALANCE AND CALIBRATION

    Energy Technology Data Exchange (ETDEWEB)

    Boersma, C.; Bregman, J.; Allamandola, L. J., E-mail: Christiaan.Boersma@nasa.gov [NASA Ames Research Center, MS 245-6, Moffett Field, CA 94035-0001 (United States)

    2016-11-20

    Low-resolution Spitzer spectral map data (>1700 spectra) of ten reflection nebulae (RNe) fields are analyzed using the data and tools available through the NASA Ames PAH IR Spectroscopic Database. The PAH emission is broken down into PAH charge state using a database fitting approach. Here, the physics of the PAH emission process is taken into account and uses target appropriate parameters, e.g., a stellar radiation model for the exciting star. The breakdown results are combined with results derived using the traditional PAH band strength approach, which interprets particular PAH band strength ratios as proxies for the PAH charge state, e.g., the 6.2/11.2 μ m PAH band strength ratio. These are successfully calibrated against their database equivalent; the PAH ionized fraction ( f {sub i} ). The PAH ionized fraction is converted into the PAH ionization parameter, which relates the PAH ionized fraction to the strength of the radiation field, gas temperature and electron density. The behavior of the 12.7 μ m PAH band is evaluated as a tracer for PAH ionization and erosion. The plot of the 8.6 versus 11.2 μ m PAH band strength for the northwest photo-dominated region (PDR) in NGC 7023 is shown to be a robust diagnostic template for the PAH ionized fraction. Remarkably, most of the other RNe fall within the limits set by NGC 7023. Finally, PAH spectroscopic templates are constructed and verified as principal components. Template spectra derived from NGC 7023 and NGC 2023 compare extremely well with each other, with those derived for NGC 7023 successfully reproducing the PAH emission observed from NGC 2023.

  8. Polycyclic aromatic hydrocarbon emissions from the combustion of alternative fuels in a gas turbine engine.

    Science.gov (United States)

    Christie, Simon; Raper, David; Lee, David S; Williams, Paul I; Rye, Lucas; Blakey, Simon; Wilson, Chris W; Lobo, Prem; Hagen, Donald; Whitefield, Philip D

    2012-06-05

    We report on the particulate-bound polycyclic aromatic hydrocarbons (PAH) in the exhaust of a test-bed gas turbine engine when powered by Jet A-1 aviation fuel and a number of alternative fuels: Sasol fully synthetic jet fuel (FSJF), Shell gas-to-liquid (GTL) kerosene, and Jet A-1/GTL 50:50 blended kerosene. The concentration of PAH compounds in the exhaust emissions vary greatly between fuels. Combustion of FSJF produces the greatest total concentration of PAH compounds while combustion of GTL produces the least. However, when PAHs in the exhaust sample are measured in terms of the regulatory marker compound benzo[a]pyrene, then all of the alternative fuels emit a lower concentration of PAH in comparison to Jet A-1. Emissions from the combustion of Jet A-1/GTL blended kerosene were found to have a disproportionately low concentration of PAHs and appear to inherit a greater proportion of the GTL emission characteristics than would be expected from volume fraction alone. The data imply the presence of a nonlinear relation between fuel blend composition and the emission of PAH compounds. For each of the fuels, the speciation of PAH compounds present in the exhaust emissions were found to be remarkably similar (R(2) = 0.94-0.62), and the results do provide evidence to support the premise that PAH speciation is to some extent indicative of the emission source. In contrast, no correlation was found between the PAH species present in the fuel with those subsequently emitted in the exhaust. The results strongly suggests that local air quality measured in terms of the particulate-bound PAH burden could be significantly improved by the use of GTL kerosene either blended with or in place of Jet A-1 kerosene.

  9. [Internal Exposure Levels of PAHs of Primary School Students in Guangzhou].

    Science.gov (United States)

    Su, Hui; Zhao, Bo; Zhang, Su-kun; Liu, Shan; Ren, Ming-zhong; Li, Jie; Shi, Xiao-xia

    2015-12-01

    In order to investigate the internal exposure levels of polycyclic aromatic hydrocarbons (PAHs) in primary school students of Guangzhou, the research collected urine of 78 and 86 primary school students from two primary schools in the summer of 2014, one school located in the ordinary residential area and the other in the industrial area. The contents of 10 kinds of OH-PAHs were tested by the rapid liquid chromatography coupled to triple quadruple tandem mass spectrometry. The results showed that the concentrations of total OH-PAHs in primary school students in the residential zone ranged from 0.83 µmol · mol⁻¹ to 80.63 µmol · mol⁻¹, while those in industrial area ranged from 1.06 µmol · mol⁻¹ to 72.47 µmol · mol⁻¹. The geometric average concentrations were 6.18 µmol · mol⁻¹ and 6.47 µmol · mol⁻¹, respectively, and there was no statistical significance between them (P > 0.05). Comparison of the exposure levels of different components of PAHs in the two areas found that all the OH-PAHs had no significant difference except for the levels of 1- OHP (P transportation emissions.

  10. The Assessment of Biofuel Utilization Policy on the Total Output and CO2 Emissions in Thailand

    Directory of Open Access Journals (Sweden)

    Suthathip Suanmali

    2013-07-01

    Full Text Available The transport sector is the largest energy-consuming sector in Thailand. Its primary energy supply is heavily depended on imported oil. Since 2005, world crude oil price has been rising and had reached a record of 147 $/barrel. Therefore the policy on promotion of biofuel utilization was initiated in 2005 by the Ministry of Energy; however, the economy-wide impacts have been rarely assessed. This paper presents the energy Input-Output Analysis (IO of the economy-wide impacts on the promotion policy, in particular, the change in Greenhouse Gas (GHG emissions. In order to measure the total GHG emission from different economic sectors, the contribution of emissions has to be considered. In this paper, the focus is placed on CO2 emissions. To calculate the amount of CO2 emissions, the emission amount of various final consumptions in the economy evaluated by the IO must be applied. The direct CO2 emissions in final energy consumptions in Thailand are evaluated by using conversion factors from Guidelines to Defra's GHG conversion factors, Annexes updated in June 2007. The CO2 emissions in various economic sectors will be calculated and compared with the figures in 2015 when the policy is fully implemented.

  11. Biodegradation, bioaccessibility, and genotoxicity of diffuse polycyclic aromatic hydrocarbon (PAH) pollution at a motorway site

    DEFF Research Database (Denmark)

    Johnsen, A.R.; de Lipthay, J.R.; Reichenberg, F.

    2006-01-01

    the asphalt pavement and tested for total amounts of PAHs, amounts of bioaccessible PAHs, total bacterial populations, PAH degrader populations, the potential for mineralization of C-14-PAHs, and mutagenicity. Elevated PAH concentrations were found in the samples taken 1-8 m from the pavement. Soil sampled...... in the most polluted samples close to the pavement. Hydroxypropyl-beta-cyclodextrin extraction of soil PAHs, as a direct estimate of the bioaccessibility, indicated that only 1-5% of the PAHs were accessible to soil bacteria. This low bioaccessibility is suggested to be due to sorption to traffic soot...... particles. The increased PAH level close to the pavement was reflected in slightly increased mutagenic activity (1 m, 0.32 +/- 0.08 revertants g(-1) soil; background/24 m: 0.08 +/- 0.04), determined by the Salmonella/microsome assay of total extractable PAHs activated by liver enzymes. The potential...

  12. Distribution of polycyclic aromatic hydrocarbons (PAHs) in surface sediments of Pulau Tinggi, Johor

    Science.gov (United States)

    Razak, Ezzati Sulhi Abdul; Halim, Izzyan Syazwani Abdul; Ali, Masni Mohd

    2016-11-01

    Surface sediments samples were collected at 11 stations around the Pulau Tinggi, Johor in September 2015. A total of 15 PAHs were determined and quantified by gas chromatography coupled with mass spectrometry (GC-MS). The total PAH concentrations of surface sediments from Pulau Tinggi ranged from 39.61 ng/g to 149.2 ng/g and they were classified as being in low to moderate pollution range. Individual PAH analysis showed that two and three rings PAHs were the most frequently detected isomers and accounted for 22 - 46% of the total PAH concentrations. The sources of PAHs were evaluated by employing diagnostic ratiosof specific PAH compounds.PAH ratios analysis showed a prevalence of pyrogenic PAH origin at most of the stations with exception of only a few stations.

  13. Polysykliske aromatiske hydrokarboner (PAH) i fisk

    OpenAIRE

    Knutzen, J.

    1987-01-01

    Det er sammenstilt litteraturdata om polysykliske aromatiske hydrokarboner (PAH, tjærestoffer) i fisk fra et lite påvirkede og fra forurensede områder og sammenlignet med utvalgte data for PAH i røkt fisk. På grunn av sparsomt og delvis tvilsomt materiale, har det bare latt seg gjøre å antyde øvre grense for et "diffust bakgrunnsnivå" av benzo(a)pyren i fiskefilet: 1 µg/kg frisk vekt. Ofte har ikke total-PAH eller utvalgte PAH-forbindelser latt seg påvise, selv i områder som vites å være mark...

  14. Time trend of polycyclic aromatic hydrocarbon emission factors from motor vehicles

    Science.gov (United States)

    Tao, Shu; Shen, Huizhong; Wang, Rong; Sun, Kang

    2010-05-01

    Motor vehicle is an important emission source of polycyclic aromatic hydrocarbons (PAHs) and this is particularly true in urban areas. Motor vehicle emission factors (EFs) for individual PAH compound reported in the literature varied for 4 to 5 orders of magnitude, leading to high uncertainty in emission estimation. In this study, the major factors affecting EFs were investigated and characterized by regression models. Based on the model developed, a motor vehicle PAH emission inventory at country level was developed. It was found that country and model year are the most important factors affecting EFs for PAHs. The influence of the two factors can be quantified by a single parameter of per capita gross domestic production (purchasing power parity), which was used as the independent variables of the regression models. The models developed using randomly selected 80% of measurements and tested with the remained data accounted for 28 to 48% of the variations in EFs for PAHs measured in 16 countries over 50 years. The regression coefficients of the EF prediction models were molecular weight dependent. Motor vehicle emission of PAHs from individual countries in the world in 1985, 1995, 2005, 2015, and 2025 were calculated and the global emission of total PAHs were 470, 390, and 430 Gg in 1985, 1995, and 2005 and will be 290 and 130 Gg in 2015 and 2025, respectively. The emission is currently passing its peak and will decrease due to significant decrease in China and other developing countries.

  15. Estimating the contributions of mobile sources of PAH to urban air using real-time PAH monitoring.

    Science.gov (United States)

    Dunbar, J C; Lin, C I; Vergucht, I; Wong, J; Duran, J L

    2001-11-12

    Motor vehicles are a significant source of airborne polycyclic aromatic hydrocarbons (PAH) in many urban areas. Traditional approaches used in determining the relative contributions of individual vehicle types to the total amount of PAH in air have been based on the analysis of integrated samples of airborne particles and gases for the presence of chemical tracers indicative of the vehicles from which the chemicals derived. As an alternative, we have used a photoelectric aerosol sensor (PAS) capable of measuring PAH levels in real-time in the emissions plumes from motor vehicles. We placed the PAS near a traffic-light in Kenmore Square, a busy crossroads in downtown Boston (MA, USA). A video camera co-located at the site recorded the vehicles passing the sensor, and this record was correlated with the PAS data. During a 5-day monitoring period (approximately 59 h) in the summer of 1998, over 34,000 motor vehicles were counted and classified and over 24,000 PAS readings were recorded (frequency = 1/8.6 s). The composition of the vehicle population was 94% passenger vehicles, 1.4% buses, 2.6% small trucks, 1.3% medium trucks, 0.35% large trucks, and 0.45% garbage and construction trucks. In analyzing the PAS data, it was assumed that the highest PAS measurements--those that exceeded the 95% critical level of the 5-min moving average of all the PAS measurements--were indicative of primary vehicular emissions. We found that approximately 46% of the mass of particle-bound PAH (i.e. approximately 46% of the integrated area under the PAS signal vs. time plots) was attributable to primary emissions from motor vehicles passing the sensor. Of this, 35-61% was attributable to passenger vehicles (cars, pickup trucks, and sports utility vehicles) and 39-65% was attributable to non-passenger vehicles [buses (14-23%), small trucks (12-20%), medium trucks (8.4-14%), large trucks (2.9-4.8%) and garbage and construction trucks (1.9-3.2%)]. Our results suggest that on a per vehicle

  16. The total hemispheric emissivity of painted aluminum honeycomb at cryogenic temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Tuttle, J.; Canavan, E.; DiPirro, M.; Li, X. [NASA Goddard Space Flight Center, Code 552 Greenbelt, Maryland, 20771 (United States); Knollenberg, P. [Northrop Grumman Aerospace Systems Redondo Beach, CA 90278 (United States)

    2014-01-29

    NASA uses high-emissivity surfaces on deep-space radiators and thermal radiation absorbers in test chambers. Aluminum honeycomb core material, when coated with a high-emissivity paint, provides a lightweight, mechanically robust, and relatively inexpensive black surface that retains its high emissivity down to low temperatures. At temperatures below about 100 Kelvin, this material performs much better than the paint itself. We measured the total hemispheric emissivity of various painted honeycomb configurations using an adaptation of an innovative technique developed for characterizing thin black coatings. These measurements were performed from room temperature down to 30 Kelvin. We describe the measurement technique and compare the results with predictions from a detailed thermal model of each honeycomb configuration.

  17. Level, potential sources of polycyclic aromatic hydrocarbons (PAHs) in particulate matter (PM10) in Naples

    Science.gov (United States)

    Di Vaio, Paola; Cocozziello, Beatrice; Corvino, Angela; Fiorino, Ferdinando; Frecentese, Francesco; Magli, Elisa; Onorati, Giuseppe; Saccone, Irene; Santagada, Vincenzo; Settimo, Gaetano; Severino, Beatrice; Perissutti, Elisa

    2016-03-01

    In Naples, particulate matter PM10 associated with polycyclic aromatic hydrocarbons (PAHs) in ambient air were determined in urban background (NA01) and urban traffic (NA02) sites. The principal objective of the study was to determine the concentration and distribution of PAHs in PM10 for identification of their possible sources (through diagnostic ratio - DR and principal component analysis - PCA) and an estimation of the human health risk (from exposure to airborne TEQ). Airborne PM10 samples were collected on quartz filters using a Low Volume Sampler (LVS) for 24 h with seasonal samples (autumn, winter, spring and summer) of about 15 days each between October 2012 and July 2013. The PM10 mass was gravimetrically determined. The PM10 levels, in all seasons, were significantly higher (P gas chromatography-mass spectrometer (GC-MS) analysis. The concentration of Benzo[a]Pyrene, BaP (EU and National limit value: 1 ng m-3 in PM10), varied from 0.065 ng m-3 during autumn time to 0.872 ng m-3 in spring time (NA01) and from 0.120 ng m-3 during autumn time to 1.48 ng m-3 of winter time (NA02) with four overshoots. In NA02 the trend of Σ12 PAHs was comparable to NA01 but were observed higher values than NA01. In fact, the mean concentration of Σ12 PAHs, in urban-traffic site was generally 2 times greater than in urban-background site in all the campaigns. PAHs with 5 and 6 ring, many of which are suspected carcinogens or genotoxic agents, (i.e Benzo[a]Pyrene, Indeno[1,2,3-cd]Pyrene, Benzo[b]Fluoranthene, Benzo[k]Fluoranthene and Benzo[g,h,i]Perylene), had a large contribution (∼50-55%) of total PAHs concentration in PM10 in two sites and in each of the campaigns. Diagnostic ratio analysis and PCA suggested a substantial contributions from traffic emission with minimal influence from coal combustion and natural gas emissions. In particular diesel vehicular emissions were the major source of PAHs at the studied sites. The use of Toxicity Equivalence Quantity (TEQ

  18. Consumption-based Total Suspended Particulate Matter Emissions in Jing-Jin-Ji Area of China

    Science.gov (United States)

    Yang, S.; Chen, S.; Chen, B.

    2014-12-01

    The highly-industrialized regions in China have been facing a serious problem of haze mainly consisted of total suspended particulate matter (TSPM), which has attracted great attention from the public since it directly impairs human health and clinically increases the risks of various respiratory and pulmonary diseases. In this paper, we set up a multi-regional input-output (MRIO) model to analyze the transferring routes of TSPM emissions between regions through trades. TSPM emission from particulate source regions and sectors are identified by analyzing the embodied TSPM flows through monetary flow and carbon footprint. The track of TSPM from origin to end via consumption activities are also revealed by tracing the product supply chain associated with the TSPM emissions. Beijing-Tianjin-Hebei (Jing-Jin-Ji) as the most industrialized area of China is selected for a case study. The result shows that over 70% of TSPM emissions associated with goods consumed in Beijing and Tianjin occurred outside of their own administrative boundaries, implying that Beijing and Tianjin are net embodied TSPM importers. Meanwhile, 63% of the total TSPM emissions in Hebei Province are resulted from the outside demand, indicating Hebei is a net exporter. In addition, nearly half of TSPM emissions are the by-products related to electricity and heating supply and non-metal mineral products in Jing-Jin-Ji Area. Based on the model results, we provided new insights into establishing systemic strategies and identifying mitigation priorities to stem TSPM emissions in China. Keywords: total suspended particulate matter (TSPM); urban ecosystem modeling; multi-regional input-output (MRIO); China

  19. Analysis of PAHs Associated with Particulate Matter PM2.5 in Two Places at the City of Cuernavaca, Morelos, México

    Directory of Open Access Journals (Sweden)

    Hugo Saldarriaga-Noreña

    2015-08-01

    Full Text Available This study was carried out between January and February 2013, at two sites in the city of Cuernavaca, México, using low-volume equipment. Fifteen Polycyclic aromatic hydrocarbons (PAHs, were identified by gas chromatography coupled with mass spectrometry. The total average concentration observed for PAHs was 24.0 ng·m−3, with the high molecular weight compounds being the most abundant. The estimated equivalent concentration for Benzo (a P (BaPE was 4.05 ng·m−3. Diagnostic ratios together with the principal components analysis (PCA allowed for establishing coal burning and vehicle emissions as being the main sources of these compounds in the area. The PAHs used to calculate this index account for 51% of the 15 PAHs identified, which probably involves a risk to the exposed population.

  20. Biodegradation, bioaccessibility, and genotoxicity of diffuse polycyclic aromatic hydrocarbon (PAH) pollution at a motorway site

    DEFF Research Database (Denmark)

    Johnsen, A.R.; de Lipthay, J.R.; Reichenberg, F.

    2006-01-01

    Diffuse pollution of surface soil with polycyclic aromatic hydrocarbons (PAHs) is problematic in terms of the large areas and volumes of polluted soil. The levels and effects of diffuse PAH pollution at a motorway site were investigated. Surface soil was sampled with increasing distance from...... in the most polluted samples close to the pavement. Hydroxypropyl-beta-cyclodextrin extraction of soil PAHs, as a direct estimate of the bioaccessibility, indicated that only 1-5% of the PAHs were accessible to soil bacteria. This low bioaccessibility is suggested to be due to sorption to traffic soot...... the asphalt pavement and tested for total amounts of PAHs, amounts of bioaccessible PAHs, total bacterial populations, PAH degrader populations, the potential for mineralization of C-14-PAHs, and mutagenicity. Elevated PAH concentrations were found in the samples taken 1-8 m from the pavement. Soil sampled...

  1. Lung cancer risk in relation to traffic-related nano/ultrafine particle-bound PAHs exposure: a preliminary probabilistic assessment.

    Science.gov (United States)

    Liao, Chung-Min; Chio, Chia-Pin; Chen, Wei-Yu; Ju, Yun-Ru; Li, Wen-Hsuan; Cheng, Yi-Hsien; Liao, Vivian Hsiu-Chuan; Chen, Szu-Chieh; Ling, Min-Pei

    2011-06-15

    Exposures to carcinogenic polycyclic aromatic hydrocarbons (PAHs) have been linked to human lung cancer. The purpose of this study was to assess lung cancer risk caused by inhalation exposure to nano/ultrafine particle-bound PAHs at the population level in Taiwan appraised with recent published data. A human respiratory tract model was linked with a physiologically based pharmacokinetic model to estimate deposition fraction and internal organic-specific PAHs doses. A probabilistic risk assessment framework was developed to estimate potential lung cancer risk. We reanalyzed particle size distribution, total-PAHs, particle-bound benzo(a)pyrene (B[a]P) and PM concentrations. A dose-response profile describing the relationships between external B[a]P concentration and lung cancer risk response was constructed based on population attributable fraction (PAF). We found that 90% probability lung cancer risks ranged from 10(-5) to 10(-4) for traffic-related nano and ultrafine particle-bound PAHs, indicating a potential lung cancer risk. The particle size-specific PAF-based excess annual lung cancer incidence rate due to PAHs exposure was estimated to be less than 1 per 100,000 population, indicating a mild risk factor for lung cancer. We concluded that probabilistic risk assessment linked PAF for limiting cumulative PAHs emissions to reduce lung cancer risk plays a prominent role in future government risk assessment program. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Exposure to dust-bound PAHs and associated carcinogenic risk in primitive and traditional cooking practices in Pakistan.

    Science.gov (United States)

    Kamal, Atif; Malik, Riffat Naseem; Martellini, Tania; Cincinelli, Alessandra

    2015-08-01

    The aim of this study was to determine the abundance and distribution of polycyclic aromatic hydrocarbons (PAHs) in dust samples collected from the selected professional cooking workplaces (WCs) and residential household cooking areas (WRs), where traditional and primitive cooking practices are still prevelent. Another aim of this study was to investigate the carcinogenic risk for Pakistani human exposure to dust-bound PAHs via the routes of inhalation, ingestion, and dermal contact. Generally, the concentration of individual congeners of PAHs in surface dust samples of WC sites was higher than those measured in WR sites (p < 0.05). The benzo(a)pyrene (B(a)P), a very high carcinogenic compound, was present in the dust samples from WC sites in the highest mean concentration (630 ng g(-1) dry weight (d.w.)). The BaP mean concentration in WC workplaces was almost eight times higher than the mean value found in WR exposure sites. Moreover, the average concentration of ∑PAHs, combustion origin PAHs (∑COMB) and sum total of 7-carcinogenic PAHs (∑7-carcinogens) were also significantly higher in WC dusts samples than that in WR workplaces. Principal component analysis (PCA) and diagnostic ratios suggested coal/wood combustion as major PAH emission sources in both exposure sites. The average incremental lifetime cancer risk (ILCR) suggested a moderate to potential high cancer risk for adults and children exposed to dust-bound PAHs in both exposure sites, in particular via both dermal and ingestion contact pathways.

  3. Migration of polycyclic aromatic hydrocarbons (PAHs) in urban treatment sludge to the air during PAH removal applications.

    Science.gov (United States)

    Karaca, Gizem; Cindoruk, S Siddik; Tasdemir, Yücel

    2014-05-01

    In the present study, the amounts of polycylic aromatic hydrocarbons (PAHs) penetrating into air during PAH removal applications from the urban treatment sludge were investigated. The effects of the temperature, photocatalyst type, and dose on the PAH removal efficiencies and PAH evaporation were explained. The sludge samples were taken from an urban wastewater treatment plant located in the city of Bursa, with 585,000 equivalent population. The ultraviolet C (UV-C) light of 254 nm wavelength was used within the UV applications performed on a specially designed setup. Internal air of the setup was vacuumed through polyurethane foam (PUF) columns in order to collect the evaporated PAHs from the sludge during the PAH removal applications. All experiments were performed with three repetitions. The PAH concentrations were measured by gas chromatography-mass spectrometry (GC-MS). It was observed that the amounts of PAHs penetrating into the air were increased with increase of temperature, and more than 80% of PAHs migrated to the air consisted of 3-ring compounds during the UV and UV-diethylamine (DEA) experiments at 38 and 53 degrees C. It was determined that 40% decrease was ensured in sigma12 (total of 12) PAH amounts with UV application and 13% of PAHs in sludge penetrated into the air. In the UV-TiO2 applications, a maximum 80% of sigma12 PAH removal was obtained by adding 0.5% TiO2 of dry weight of sludge. The quantity of PAH penetrating into air did not exceed 15%. UV-TiO2 applications ensured high levels of PAH removal in the sludge and also reduced the quantity of PAH penetrating into the air. Within the scope of the samples added with DEA, there was no increase in PAH removal efficiencies and the penetration of PAHs into air was not decreased. In light of these data, it was concluded that UV-TiO2 application is the most suitable PAH removal alternative that restricts the convection of PAH pollution.

  4. Infrared spectra of interstellar deuteronated PAHs

    Science.gov (United States)

    Buragohain, Mridusmita; Pathak, Amit; Sarre, Peter

    2015-08-01

    Polycyclic Aromatic Hydrocarbon (PAH) molecules have emerged as a potential constituent of the ISM that emit strong features at 3.3, 6.2, 7.7, 8.6, 11.2 and 12.7 μm with weaker and blended features in the 3-20μm region. These features are proposed to arise from the vibrational relaxation of PAH molecules on absorption of background UV photons (Tielens 2008). These IR features have been observed towards almost all types of astronomical objects; say H II regions, photodissociation regions, reflection nebulae, planetary nebulae, young star forming regions, external galaxies, etc. A recent observation has proposed that interstellar PAHs are major reservoir for interstellar deuterium (D) (Peeters et al. 2004). According to the `deuterium depletion model' as suggested by Draine (2006), some of the Ds formed in the big bang are depleted in PAHs, which can account for the present value of D/H in the ISM. Hence, study of deuterated PAHs (PADs) is essential in order to measure D/H in the ISM.In this work, we consider another probable category of the large PAH family, i.e. Deuteronated PAHs (DPAH+). Onaka et al. have proposed a D/H ratio which is an order of magnitude smaller than the proposed value of D/H by Draine suggesting that if Ds are depleted in PAHs, they might be accommodated in large PAHs (Onaka et al. 2014). This work reports a `Density Functional Theory' calculation of large deuteronated PAHs (coronene, ovalene, circumcoronene and circumcircumcoronene) to determine the expected region of emission features and to find a D/H ratio that is comparable to the observational results. We present a detailed analysis of the IR spectra of these molecules and discuss the possible astrophysical implications.ReferencesDraine B. T. 2006, in ASP Conf. Ser. 348, Proc. Astrophysics in the Far Ultraviolet: Five Years of Discovery with FUSE, ed. G. Sonneborn, H. Moos, B-G Andersson (San Francisco, CA:ASP) 58Onaka T., Mori T. I., Sakon I., Ohsawa R., Kaneda H., Okada Y., Tanaka M

  5. Cloud deposition of PAHs at Mount Lushan in southern China.

    Science.gov (United States)

    Wang, Ruixia; Wang, Yan; Li, Hongli; Yang, Minmin; Sun, Lei; Wang, Tao; Wang, Wenxing

    2015-09-01

    Cloud water samples were collected from Mount Lushan, a high alpine area of southern China, and analyzed using GC-MS to investigate the concentration levels, seasonal variations, particle-dissolved phase partitioning, ecological risk of PAHs and its relationship to the atmosphere and rainwater. The average concentration of total (dissolved+particle) PAHs in cloud water was 819.90 ng/L, which ranged from 2.30 ng/L for DbA to 295.38 ng/L for PhA. PhA (33.11%) contributed the most individual PAHs, followed by Flu (28.24%). Distinct seasonal variations in the total PAHs measured in this research had a higher concentration during the spring and a lower concentration during the summer. When cloud events occurred, the concentration of the atmospheric PAHs of the two phases decreased. The contribution from the gaseous phase of total PAHs in the air to the dissolved phase in cloud water was up to 60.43%, but the particulate phase in the air only contributed 39.57% to the total scavenging. The contribution of total PAHs from the atmosphere to clouds is higher in the gaseous phase than in the particulate phase. A comparative study of the concentrations of cloud water and the closest rain water revealed that the PAH concentration in rainwater was 1.80 times less than that of cloud water and that the dominant individual compounds in cloud water and rainwater were PhA and Flu. A total of 81.27% of the PAHs in cloud samples and 72.21% of the PAHs in rain samples remained in the dissolved phase. Ecological risk assessment indicated that PAHs in cloud water in spring and summer caused a certain degree of ecosystem risk and the mean ecosystem risk in spring was higher than that in summer. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. [Concentrations and Component Profiles PAHs in Surface Soils and Wheat Grains from the Cornfields Close to the Steel Smelting Industry in Handan, Hebei Province].

    Science.gov (United States)

    Wu, Di; Wang, Yi-long; Liu, Wei-jian; Chen, Yuan-chen; Fu, Xiao-fang; Tao, Shu; Liu, Wen-xin

    2016-02-15

    In this study, paired surface soil and mature wheat grain samples were collected in the cornfields near the large Handan Steel Manufacturer; and the total concentrations and compositional profiles of the parent PAHs were measured, then the spatial distribution characteristics and correlation with total organic carbon fractions in soil were determined. Accordingly, a preliminary source identification was performed, and the association between PAHs in surface soil and wheat grain was briefly discussed. The median concentration of total PAHs in surface soils from the cornfields of Handan was 398.9 ng x g(-1) (ranged from 123.4 ng x g(-1) to 1626.4 ng x g(-1), where around 18% and 10% of all the studied soil samples were over the corresponding quality criteria for total PAHs and B [a] P in soils, respectively. The MMW and HMW species were the main components in the compositional profiles of surface soils. Based on the specific isomeric ratios of PAHs species, coal/biomass combustion and transportation fuel (tail gas) were the dominant mixed sources for the local PAHs emission. The fractions of surface soil TOC had significant positive correlations with the total PAHs and also with the individual components with different rings. In addition, the median concentration of total PAHs in wheat grains collected in the cornfields near the Handan Steel Manufacture was 27.0 ng x g(-1) (ranged from 19.0-34.0 ng x g(-1)). The levels in wheat grains were not high, and lower than the related hygienic standards of food proposed by EU and China. The LMW and MMW PAHs with 2 to 4 rings occupied a larger proportion, more than 84% of the total PAHs, which was largely different from the component profiles in surface soils. This situation suggested that the local sources of PAHs in wheat grains may originate not only from surface soil via root absorption and internal transportation, but also from ambient air through dry and wet deposition on the leaf surface (stoma).

  7. Emission characteristics and size distribution of polycyclic aromatic hydrocarbons from coke production in China

    Science.gov (United States)

    Mu, Ling; Peng, Lin; Liu, Xiaofeng; He, Qiusheng; Bai, Huiling; Yan, Yulong; Li, Yinghui

    2017-11-01

    Coking is regarded as a major source of atmospheric polycyclic aromatic hydrocarbons (PAHs), but few researches have been conducted on the emission characteristics of PAHs from coke production. In this study, emissions of size-segregated particulate matter (PM) and particle-bound PAHs emitted from charging of coal (CC) and pushing of coke (PC) in four typical coke plants were determined. The emission factors on average, sums of CC and PC, were 4.65 mg/kg, 5.96 mg/kg, 19.18 μg/kg and 20.69 μg/kg of coal charged for PM2.1 (≤ 2.1 μm), PM, PAHs in PM2.1 and total-PAHs, respectively. PM and PAHs emission from plants using stamp charging were significantly more than those using top charging. The profile of PAHs in PM with size ≤ 1.4 μm (PM1.4) emitted from CC process were similar with that from PC, however, it revealed obviously different tendency for PAHs in PM with size > 1.4 μm, indicating the different formation mechanism for coarse particles emitted from CC and PC. Size distributions of PM and PAHs indicated that they were primarily connected with PM1.4, and the contributions of PM1.4 to PM and PAHs emitted from the plants using stamp charging were higher than those using top charging. Some improved technology in air-pollution control devices should be considered in coke production in future based on the considerable impacts of PM1.4 and PAHs on human health and ambient air quality.

  8. Effects of particulate oxidation catalyst on unregulated pollutant emission and toxicity characteristics from heavy-duty diesel engine.

    Science.gov (United States)

    Feng, Xiangyu; Ge, Yunshan; Ma, Chaochen; Tan, Jianwei

    2015-01-01

    To evaluate the effects of particulate oxidation catalyst (POC) on unregulated pollutant emission and toxicity characteristics, polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds (VOCs), soot, soluble organic fractions (SOF) and sulphate emissions emitted from a heavy-duty diesel engine retrofitted with a POC were investigated on a diesel bench. The particulate matter (PM) in the exhaust was collected by Teflon membrane, and the PAHs and VOCs were analysed by a gas chromatography/mass spectrometer (GC/MS). The results indicate that the POC exhibits good performance on the emission control of VOCs, PAHs and PM. The POC and the diesel particulate filters (DPF) both show a good performance on reducing the VOCs emission. Though the brake-specific emission (BSE) reductions of the total PAHs by the POC were lower than those by the DPF, the POC still removed almost more than 50% of the total PAHs emission. After the engine was retrofitted with the POC, the reductions of the PM mass, SOF and soot emissions were 45.2-89.0%, 7.8-97.7% and 41.7-93.3%, respectively. The sulphate emissions decreased at low and medium loads, whereas at high load, the results were contrary. The PAHs emissions were decreased by 32.4-69.1%, and the contributions of the PAH compounds were affected by the POC, as well as by load level. The benzo[a]pyrene equivalent (BaPeq) of PAHs emissions were reduced by 35.9-97.6% with the POC. The VOCs emissions were reduced by 21.8-94.1% with the POC, and the reduction was more evident under high load.

  9. Effect of Smoking on Polycyclic Aromatic Hydrocarbons (PAHS ...

    African Journals Online (AJOL)

    ADOWIE PERE

    Manage. Vol. 22 (2) 293 - 297. February 2018. Full-text Available Online at ... aromatic hydrocarbons (PAHs) were studied in raw and smoked samples of catfish (Clarias ... inferred that the smoking process generally increased the mean total PAH levels in the fish .... with 5 g of anhydrous sodium sulphate in a laboratory.

  10. Ability of natural attenuation and phytoremediation using maize (Zea mays L.) to decrease soil contents of polycyclic aromatic hydrocarbons (PAHs) derived from biomass fly ash in comparison with PAHs-spiked soil.

    Science.gov (United States)

    Košnář, Zdeněk; Mercl, Filip; Tlustoš, Pavel

    2018-05-30

    A 120-day pot experiment was conducted to compare the ability of natural attenuation and phytoremediation approaches to remove polycyclic aromatic hydrocarbons (PAHs) from soil amended with PAHs-contaminated biomass fly ash. The PAH removal from ash-treated soil was compared with PAHs-spiked soil. The removal of 16 individual PAHs from soil ranged between 4.8% and 87.8% within the experiment. The natural attenuation approach led to a negligible total PAH removal. The phytoremediation was the most efficient approach for PAH removal, while the highest removal was observed in the case of ash-treated soil. The content of low molecular weight (LMW) PAHs and the total PAHs in this treatment significantly decreased (P <.05) over the whole experiment by 47.6% and 29.4%, respectively. The tested level of PAH soil contamination (~1600 µg PAH/kg soil dry weight) had no adverse effects on maize growth as well on the biomass yield. In addition, the PAHs were detected only in maize roots and their bioaccumulation factors were significantly lower than 1 suggesting negligible PAH uptake from soil by maize roots. The results showed that PAHs of ash origin were similarly susceptible to removal as spiked PAHs. The presence of maize significantly boosted the PAH removal from soil and its aboveground biomass did not represent any environmental risk. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. Grafted cellulose for PAHs removal present in industrial discharge waters

    Science.gov (United States)

    Euvrard, Elise; Druart, Coline; Poupeney, Amandine; Crini, Nadia; Vismara, Elena; Lanza, Tommaso; Torri, Giangiacomo; Gavoille, Sophie; Crini, Gregorio

    2014-05-01

    Keywords: cellulose; biosorbent; PAHs; polycontaminated wastewaters; trace levels. Polycyclic aromatic hydrocarbons (PAHs), chemicals essentially formed during incomplete combustion of organic materials from anthropogenic activities, were present in all compartments of the ecosystem, air, water and soil. Notably, a part of PAHs found in aquatic system was introduced through industrial discharge waters. Since the Water Framework Directive has classified certain PAHs as priority hazardous substances, industrials are called to take account this kind of organic pollutants in their global environmental concern. Conventional materials such as activated carbons definitively proved their worth as finishing treatment systems but remained costly. In this study, we proposed to use cellulose grafted with glycidyl methacrylate [1] for the removal of PAHs present in discharge waters of surface treatment industries. Firstly, to develop the device, we worked with synthetic solutions containing 16 PAHs at 500 ng/L. Two types of grafted cellulose were tested over a closed-loop column with a concentration of 4g cellulose/L: cellulose C2 with a hydroxide group and cellulose C4 with an amine group. No PAH was retained by the raw cellulose whereas abatement percentages of PAHs were similar between C2 and C4 (94% and 98%, respectively, for the sum of the 16 PAHs) with an experiment duration of 400 min (corresponding to about 20 cycles through grafted cellulose). Secondly, to determine the shorter time to abate the amount maximum of PAHs through the system, a kinetic was realized from 20 min (one cycle) to 400 min with C4. The steady state (corresponding to about 95% of abatement of the total PAHs) was reached at 160 min. Finally, the system was then tested with real industrial discharge waters containing both mineral and organic compounds. The results indicated that the abatement percentage of PAHs was similar between C2 and C4, corroborating the tests with synthetic solution. In return

  12. PAH in Some Brands of Tea and Coffee

    DEFF Research Database (Denmark)

    Duedahl-Olesen, Lene; Navaratnam, Marin Arosha; Jewula, J.

    2015-01-01

    The presence of 25 polycyclic aromatic hydrocarbons (PAHs) in tea and coffee were investigated with focus on four PAHs (PAH4), classified by the European Food Safety Authority (EFSA) as suitable indicators; benz[a]anthracene (BaA), chrysene (CHR), benzo[b]fluoranthene (BbF) and benzo[a]pyrene (Ba......P). PAH4 from samples of 18 brands of tea leaves and 13 brands of coffee were extracted by pressurized liquid extraction (PLE) followed by highly automated clean up steps for gel permeation chromatography (SX-3) and solid phase extraction (500mg silica). GC-MS were applied for detection of PAH4. The limit...... of detection (LOD) ranged from 0.1–0.3 μg/kg with recoveries from 94–106% for PAH4. Concentrations of PAH4 followed the pattern of the total sum of 25 PAHs with higher concentrations with a maximum of 115 μg/kg in tea leaves compared to 5.1 μg/kg in coffee. The highest PAH4 levels were found in black tea...

  13. Kandungan Senyawa Polisiklik Aromatik Hidrokarbon (PAH di Teluk Jakarta (Polycyclic Aromatic Compounds Hydrocarbons (PAH Content in Jakarta Bay

    Directory of Open Access Journals (Sweden)

    Fasmi Ahmad

    2013-07-01

    Full Text Available Perairan Teluk Jakarta menerima limbah yang berasal dari darat maupun perairan itu sendiri. Salah satu limbah tersebut adalah senyawa organik Polisiklik Aromatik Hidrokarbon (PAH yang merupakan senyawa organik bersifat toksik terhadap biota laut. Penelitian dilakukan untuk mengetahui kandungan PAH air laut dan sedimen dalam kaitannya dengan kehidupan biota laut serta mengetahui sumber senyawa tersebut. Pengukuran dilakukan bulan Maret 2011. Contoh air laut diambil dengan water sampler dan contoh sedimen dengan grab pada 15 stasiun. Kadar PAH dianalisa dengan Gas Chromatography-Flame Ionization Detector. Hasil penelitian menunjukkan kadar PAH air laut di Teluk Jakarta Bagian Barat > Bagian Tengah > Bagian Timur. Kandungan PAH di Teluk Jakarta Bagian Barat berkisar 201,57-474,68 ppb dengan total PAH 1404,68 ppb, di Bagian Tengah 104,61-337,07 ppb dengan total 825,63 ppb, dan di Bagian Timur 112,91-370,79 ppb dengan total 806,73 ppb. Data ini menunjukkan Teluk Jakarta Bagian Barat lebih banyak menerima masukan limbah yang mengandung PAH. Sedangkan Kadar PAH sedimen di Teluk Jakarta Bagian Timur > Bagian Tengah > Bagian Barat. Kadar PAH di Teluk Jakarta Bagian Barat berkisar 1,92-64,241 ppm dengan total 107,931 ppm, di Bagian Tengah 16,14-77,71 ppm dengan total 170,61 ppm, dan di Bagian Timur 8,72-115,39 ppm dengan total 252,25 ppm. Data ini menunjukkan sedimen di Teluk Jakarta Bagian Timur lebih banyak mengakumulasi limbah yang mengandung PAH. Sumber PAH dalam air laut dan sedimen ini berasal dari berbagai sumber yakni pembakaran bahan organik, pembakaran minyak bumi, dan tumpahan minyak. Kadar PAH dalam air laut di Teluk Jakarta ini telah melebihi Nilai Ambang Batas yang ditetapkan oleh KMNLH untuk biota laut, dan Nilai Ambang Batas untuk sedimen yang ditetapkan oleh Handbook for Sediment Quality Assessment. Kata kunci: Teluk Jakarta, Polisiklik Aromatik Hidrokarbon, PAH, polusi Jakarta Bay receives various kinds of waste both from land and waters

  14. Is black carbon a better predictor of polycyclic aromatic hydrocarbon distribution in soils than total organic carbon?

    International Nuclear Information System (INIS)

    Agarwal, Tripti; Bucheli, Thomas D.

    2011-01-01

    Black carbon (BC) and total organic carbon (TOC) were quantified in the surface soils of Switzerland (N = 105) and Delhi (N = 36), India, to examine their relationships with contents of polycyclic aromatic hydrocarbons (PAH). BC content in Swiss (background) soils (N = 104) varied from 0.41 to 4.75 mg/g (median: 1.13 mg/g) and constituted 1-9% (median: 3%) of TOC. Indian (urban) soils had similar BC concentrations (0.37-2.05 mg/g, median: 1.19 mg/g), with relatively higher BC/TOC (6-23%, median: 13%). Similar to TOC, BC showed significant positive correlation with lighter PAH, but no correlation with heavier PAH in Swiss soils. In contrast, heavier PAH were significantly correlated only with BC in Delhi soils. It seems that TOC governs the distribution of PAH in organic matter rich background soils, while the proximity to emission sources is reflected by BC-PAH association in urban soils. - Light PAH correlated with TOC in background soils, whereas heavy PAH were associated with BC close to emission sources.

  15. PAH processing in space

    NARCIS (Netherlands)

    Micelotta, Elisabetta Rita

    2009-01-01

    Polycyclic Aromatic Hydrocarbons (PAHs) are one of the most common chemical compounds on Earth. These big molecules are naturally present in crude oil and coal deposits, and are also formed by incomplete combustion of carbon-containing fuels, hence they are found in car exhaust, cigarette smoke and

  16. Measurement of polynuclear aromatic hydrocarbons (PAHs) in epiphytic lichens and from PM 2.5 filters for receptor modeling in the Alberta Oil Sands Region (Invited)

    Science.gov (United States)

    Studabaker, W. B.; Jayanty, J.; Raymer, J. H.; Krupa, S.

    2013-12-01

    As mining and refinery operations in the Alberta Oil Sands Region (AOSR) have expanded, there has been increasing concern for the impacts of air pollution generated by those operations on both human and ecosystem health. The inaccessibility of much of the AOSR makes it difficult to establish conventional air quality monitoring stations to the extent needed to model long-range impacts of emissions from the AOSR operations. Epiphytic lichens are important markers of ecosystem health, are well-established bioaccumulators of trace metals, and are potentially useful biomonitors of air pollution. However, their ability to take up organic pollutants has not been extensively explored, and only recently have they been used for biomonitoring of pollution by PAHs. Here we describe the determination of polynuclear aromatic hydrocarbons (PAHs) in lichens, collected from sites throughout the AOSR, for modeling emissions associated with mining and oil extraction operations. We also describe preliminary results of the determination of PAHs in PM 2.5 filters from dichotomous samplers stationed in the AOSR, in the context of the biological sample data. Lichens (Hypogymnia physodes) were collected on two separate occasions. During the summer of 2009, single samples were taken from 200 sites in the AOSR; a subset of 20 of these was selected for determination of PAHs. During the summer of 2011, triplicate samples (from separate trees within a site) were collected from 20 sites representing similar locations to the 2008 sites. Lichens were milled in a cryogenic impactor, then were extracted with cyclohexane. Extracts were purified on silica gel using automated solid phase extraction and analyzed by gas chromatography with mass selective detection. Method detection limits for individual PAHs were 2-4 ng/g. Total PAHs in the samples from both collection events ranged from 50 ng/g to 350 ng/g, and declined with increasing distance from the mining and refinery operations. The relative

  17. Vegetative cover and PAHs accumulation in soils of urban green space

    International Nuclear Information System (INIS)

    Peng Chi; Ouyang Zhiyun; Wang Meie; Chen Weiping; Jiao Wentao

    2012-01-01

    We investigated how urban land uses influence soil accumulation of polycyclic aromatic hydrocarbons (PAHs) in the urban green spaces composed of different vegetative cover. How did soil properties, urbanization history, and population density affect the outcomes were also considered. Soils examined were obtained at 97 green spaces inside the Beijing metropolis. PAH contents of the soils were influenced most significantly by their proximity to point source of industries such as the coal combustion installations. Beyond the influence circle of industrial emissions, land use classifications had no significant effect on the extent of PAH accumulation in soils. Instead, the nature of vegetative covers affected PAH contents of the soils. Tree–shrub–herb and woodland settings trapped more airborne PAH and soils under these vegetative patterns accumulated more PAHs than those of the grassland. Urbanization history, population density and soil properties had no apparent impact on PAHs accumulations in soils of urban green space. - Highlights: ► Land use did not affect PAHs in soils except for areas adjacent to industrial sources. ► Tree–shrub–herb and woodland cover amass more PAHs in soils than grassland cover. ► Urban development and soil property factors had little effect on PAHs in soils. - Industrial emissions aside, vegetative cover is the dominant factor controlling accumulation of PAHs in urban green space soils.

  18. Relation between PAH and black carbon contents in size fractions of Norwegian harbor sediments

    International Nuclear Information System (INIS)

    Oen, Amy M.P.; Cornelissen, Gerard; Breedveld, Gijs D.

    2006-01-01

    Distributions of total organic carbon (TOC), black carbon (BC), and polycyclic aromatic hydrocarbons (PAH) were investigated in different particle size fractions for four Norwegian harbor sediments. The total PAH (16-EPA) concentrations ranged from 2 to 113 mg/kg dry weight with the greatest fraction of PAH mass in the sand fraction for three of the four sediments. TOC contents ranged from 0.84% to 14.2% and BC contents from 0.085% to 1.7%. This corresponds to organic carbon (OC = TOC - BC) contents in the range of 0.81-14% and BC:TOC ratios of 1.3-18.1%. PAH isomer ratios suggested that the PAH in all four sediments were of pyrogenic origin. Furthermore, stronger correlations between PAH versus BC (r 2 = 0.85) than versus OC (r 2 = 0.15) were found. For all size fractions and bulk sediments, the PAH-to-BC ratios for the total PAHs were on average 6 ± 3 mg PAH/g BC. These results suggest that PAH distributions were dominated by the presence of BC, rather than OC. As sorption to BC is much stronger than sorption to OC, this may result in significantly lower dissolved concentrations of PAH than expected on the basis of organic carbon partitioning alone. - PAH contents correlated better with black carbon than organic carbon for four Norwegian harbor sediments

  19. Spatial Variability of PAHs and Microbial Community Structure in Surrounding Surficial Soil of Coal-Fired Power Plants in Xuzhou, China.

    Science.gov (United States)

    Ma, Jing; Zhang, Wangyuan; Chen, Yi; Zhang, Shaoliang; Feng, Qiyan; Hou, Huping; Chen, Fu

    2016-09-02

    This work investigated the spatial profile and source analysis of polycyclic aromatic hydrocarbons (PAHs) in soil that surrounds coal-fired power plants in Xuzhou, China. High-throughput sequencing was employed to investigate the composition and structure of soil bacterial communities. The total concentration of 15 PAHs in the surface soils ranged from 164.87 to 3494.81 μg/kg dry weight. The spatial profile of PAHs was site-specific with a concentration of 1400.09-3494.81 μg/kg in Yaozhuang. Based on the qualitative and principal component analysis results, coal burning and vehicle emission were found to be the main sources of PAHs in the surface soils. The phylogenetic analysis revealed differences in bacterial community compositions among different sampling sites. Proteobacteria was the most abundant phylum, while Acidobacteria was the second most abundant. The orders of Campylobacterales, Desulfobacterales and Hydrogenophilales had the most significant differences in relative abundance among the sampling sites. The redundancy analysis revealed that the differences in bacterial communities could be explained by the organic matter content. They could also be explicated by the acenaphthene concentration with longer arrows. Furthermore, OTUs of Proteobacteria phylum plotted around particular samples were confirmed to have a different composition of Proteobacteria phylum among the sample sites. Evaluating the relationship between soil PAHs concentration and bacterial community composition may provide useful information for the remediation of PAH contaminated sites.

  20. Distribution of Gas Phase Polycyclic Aromatic Hydrocarbons (PAHs in Selected Indoor and Outdoor Air Samples of Malaysia: a Case Study in Serdang, Selangor and Bachang, Malacca

    Directory of Open Access Journals (Sweden)

    Haris Hafizal Abd Hamid

    2017-07-01

    Full Text Available Distribution of 10 polycyclic aromatic hydrocarbons (PAHs in the gas phase of air from selected indoor and outdoor areas of Selangor and Malacca, Malaysia has been investigated. A locally designed Semi Permeable Membrane Device (SPMD was applied for passive air sampling for 37 days at selected locations. Cleanup was carried out with Gas Purge - Micro Syringe Extraction (GP-MSE and the final analysis was using Gas Chromatography-Mass Spectrometry (GC-MS. In this study, 6 indoor and 12 outdoor locations were selected for air sampling. A total of 10 compounds of PAHs (Ʃ10PAHs were determined in the range of 0.218 ng/m3 - 1.692 ng/m3 and 0.378 ng/m3 - 1.492 ng/m3 in outdoor and indoor samples respectively. In the outdoor samples, locations such as near a petrol station and heavy traffic showed the maximum levels of Ʃ10PAHs, while rooftop samples showed the lowest Ʃ10PAHs. The distribution of gas phase Ʃ10PAHs was influenced by vehicular emission. Low molecular weight (LMW compounds (2-3 rings were dominant in all samples (>70% indicating that SPMD has successfully sampled the gas phase of the air.

  1. Concentrations, sources and health effects of parent, oxygenated- and nitrated- polycyclic aromatic hydrocarbons (PAHs) in middle-school air in Xi'an, China

    Science.gov (United States)

    Wang, Jingzhi; Xu, Hongmei; Guinot, Benjamin; Li, Lijuan; Ho, Steven Sai Hang; Liu, Suixin; Li, Xiaoping; Cao, Junji

    2017-08-01

    Indoor and outdoor concentrations of polycyclic aromatic hydrocarbons (PAHs), oxygenated-PAHs (OPAHs), and nitro-PAHs (NPAHs) associated with PM2.5 particles were monitored in a middle-school classroom from 8 to 22 March 2012 in Xi'an, China. The total PAHs ranged from 49.6 to 140.0 ng/m3 in outdoors and 50.3 to 111.6 ng/m3 in indoors, while OPAHs and NPAHs showed averages of 19.1 and 16.4 ng/m3, 0.1039 and 0.0785 ng/m3 for outdoor and indoor air, respectively. Strong correlations were found between indoor (I) and outdoor (O), and the I/O ratios were school in Xi'an. Indoor pollutants were mostly influenced by outdoor air. Biomass burning, coal combustion, and vehicle emission were main sources for PAHs. Secondary formation was the main source for OPAHs and NPAHs. Inhalation cancer risks assessment of PAHs showed there were potential health risks for students during sampling time.

  2. Spatial Variability of PAHs and Microbial Community Structure in Surrounding Surficial Soil of Coal-Fired Power Plants in Xuzhou, China

    Directory of Open Access Journals (Sweden)

    Jing Ma

    2016-09-01

    Full Text Available This work investigated the spatial profile and source analysis of polycyclic aromatic hydrocarbons (PAHs in soil that surrounds coal-fired power plants in Xuzhou, China. High-throughput sequencing was employed to investigate the composition and structure of soil bacterial communities. The total concentration of 15 PAHs in the surface soils ranged from 164.87 to 3494.81 μg/kg dry weight. The spatial profile of PAHs was site-specific with a concentration of 1400.09–3494.81 μg/kg in Yaozhuang. Based on the qualitative and principal component analysis results, coal burning and vehicle emission were found to be the main sources of PAHs in the surface soils. The phylogenetic analysis revealed differences in bacterial community compositions among different sampling sites. Proteobacteria was the most abundant phylum, while Acidobacteria was the second most abundant. The orders of Campylobacterales, Desulfobacterales and Hydrogenophilales had the most significant differences in relative abundance among the sampling sites. The redundancy analysis revealed that the differences in bacterial communities could be explained by the organic matter content. They could also be explicated by the acenaphthene concentration with longer arrows. Furthermore, OTUs of Proteobacteria phylum plotted around particular samples were confirmed to have a different composition of Proteobacteria phylum among the sample sites. Evaluating the relationship between soil PAHs concentration and bacterial community composition may provide useful information for the remediation of PAH contaminated sites.

  3. PCDD/F, PCB, HXCBZ, PAH, AND PM EMISSION FACTORS FOR FIREPLACE AND WOODSTOVE COMBUSTION IN THE SAN FRANCISCO BAY REGION

    Science.gov (United States)

    Emissions from residential fireplace and woodstove appliances burning fuels available from the San Francisco Bay area were sampled for polychlornated dibenzodioxins and dibenzofurans (PCDDs/Fs), polychlorinated biphenyls (PCBs), hexachlorobenzene (HxCBz), particulatematter (P...

  4. Characterization and concentrations of polycyclic aromatic hydrocarbons in emissions from different heating systems in Damascus, Syria.

    Science.gov (United States)

    Alkurdi, Farouk; Karabet, François; Dimashki, Marwan

    2014-04-01

    Traffic has long been recognized as the major contributor to polycyclic aromatic hydrocarbon (PAH) emissions to the urban atmosphere. Stationary combustion sources, including residential space heating systems, are also a major contributor to PAH emissions. The aim of this study was to determine the profile and concentration of PAHs in stack flue gas emissions from different kinds of space heaters in order to increase the understanding of the scale of the PAH pollution problem caused by this source. This study set out to first assess the characteristics of PAHs and their corresponding benzo[a]pyrene equivalent emissions from a few types of domestic heaters and central heating systems to the urban atmosphere. The study, enabled for the first time, the characterization of PAHs in stationary combustion sources in the city of Damascus, Syria. Nine different types of heating systems were selected with respect to age, design, and type of fuel burned. The concentrations of 15 individual PAH compounds in the stack flue gas were determined in the extracts of the collected samples using high-performance liquid chromatography system (HPLC) equipped with ultraviolet-visible and fluorescence detectors. In general, older domestic wood stoves caused considerably higher PAH emissions than modern domestic heaters burning diesel oil. The average concentration of ΣPAH (sum of 15 compounds) in emissions from all types of studied heating systems ranged between 43 ± 0.4 and 316 ± 1.4 μg/m(3). Values of total benzo[a]pyrene equivalent ranged between 0.61 and 15.41 μg/m(3).

  5. Toxic assessment of urban atmospheric particle-bound PAHs: Relevance of composition and particle size in Barcelona (Spain)

    International Nuclear Information System (INIS)

    Mesquita, Sofia Raquel; Drooge, Barend L. van; Reche, Cristina; Guimarães, Laura; Grimalt, Joan O.; Barata, Carlos; Piña, Benjamin

    2014-01-01

    Zebrafish embryotoxicity and dioxin-like activity levels were tested for particulate air samples from an urban background site in Barcelona (Spain). Samples were collected during 14 months, and maximal values for both biological activities corresponded to samples collected during late autumn months, correlating with elevated PAH levels. Vehicle and combustion emissions appeared as the potentially most toxic sources, whereas total PM mass and mineral content appeared to be poor predictors of the biological activity of the samples. Samples simultaneously collected at different particle size cut-offs (10, 2.5, and 1 μm) did not differ significantly in dioxin-like PAH levels and biological activity, indicating that the sub-micron particle fraction (PM 1 ) concentrated essentially all observed toxicity. Our results support the need for a tighter control on sub-micron particle emissions and show that total PM mass and, particularly, PM 10 , may not fully characterize the toxic potential of air samples. Highlights: • Dioxin-like activity was found in all air particle samples collected in Barcelona. • 50% of the samples showed different levels of fish embryotoxicity. • Toxic effects associated to PAHs and linked to vehicle and combustion emissions. • The toxicity was not correlated to PM mass or mineral content. • The sub-micron particle fraction PM 1 concentrated essentially all observed toxicity. -- In vivo toxic effects associated to sub-micron urban air particles from combustion and vehicle emissions

  6. Steps Toward Identifying PAHs: A Child's Garden of Recent Results

    Science.gov (United States)

    Hudgins, Douglas M.

    2005-01-01

    Based on over two decades of experimental, observational and theoretical studies by scientists around the world. It is now widely accepted that the composite emission of mixtures of vibrationally-excited PAHs and PAH ions can accommodate the general pattern of band positions, intensities, and profiles observed in the discreet IR emission features of carbon-rich interstellar dust, as well as the variations in those characteristics. These variations provide insight into the detailed nature of the emitting PAH population and reflect conditions within the emitting regions giving the population enormous potential as probes of astrophysical environments. Moreover, the ubiquity and abundance of this material has impacts that extend well beyond the IR. In this presentation we will examine recent, combined experimental, theoretical, and observational studies that indicate that nitrogen-substituted PAHs represent an important component of the interstellar dust population, and we will go on to explore some of the ramifications of this result. We will also explore the results of recent experimental studies of the strong, low-lying electronic transitions of ionized PAH ions in the Near-IR (0.7 - 2.5 microns) and explore the role that these transitions might play in pumping the PAH IR emission in regions of low-excitation.

  7. Emissions databases for polycyclic aromatic compounds in the Canadian Athabasca oil sands region - development using current knowledge and evaluation with passive sampling and air dispersion modelling data

    Science.gov (United States)

    Qiu, Xin; Cheng, Irene; Yang, Fuquan; Horb, Erin; Zhang, Leiming; Harner, Tom

    2018-03-01

    Two speciated and spatially resolved emissions databases for polycyclic aromatic compounds (PACs) in the Athabasca oil sands region (AOSR) were developed. The first database was derived from volatile organic compound (VOC) emissions data provided by the Cumulative Environmental Management Association (CEMA) and the second database was derived from additional data collected within the Joint Canada-Alberta Oil Sands Monitoring (JOSM) program. CALPUFF modelling results for atmospheric polycyclic aromatic hydrocarbons (PAHs), alkylated PAHs, and dibenzothiophenes (DBTs), obtained using each of the emissions databases, are presented and compared with measurements from a passive air monitoring network. The JOSM-derived emissions resulted in better model-measurement agreement in the total PAH concentrations and for most PAH species concentrations compared to results using CEMA-derived emissions. At local sites near oil sands mines, the percent error of the model compared to observations decreased from 30 % using the CEMA-derived emissions to 17 % using the JOSM-derived emissions. The improvement at local sites was likely attributed to the inclusion of updated tailings pond emissions estimated from JOSM activities. In either the CEMA-derived or JOSM-derived emissions scenario, the model underestimated PAH concentrations by a factor of 3 at remote locations. Potential reasons for the disagreement include forest fire emissions, re-emissions of previously deposited PAHs, and long-range transport not considered in the model. Alkylated PAH and DBT concentrations were also significantly underestimated. The CALPUFF model is expected to predict higher concentrations because of the limited chemistry and deposition modelling. Thus the model underestimation of PACs is likely due to gaps in the emissions database for these compounds and uncertainties in the methodology for estimating the emissions. Future work is required that focuses on improving the PAC emissions estimation and

  8. Emissions databases for polycyclic aromatic compounds in the Canadian Athabasca oil sands region – development using current knowledge and evaluation with passive sampling and air dispersion modelling data

    Directory of Open Access Journals (Sweden)

    X. Qiu

    2018-03-01

    Full Text Available Two speciated and spatially resolved emissions databases for polycyclic aromatic compounds (PACs in the Athabasca oil sands region (AOSR were developed. The first database was derived from volatile organic compound (VOC emissions data provided by the Cumulative Environmental Management Association (CEMA and the second database was derived from additional data collected within the Joint Canada–Alberta Oil Sands Monitoring (JOSM program. CALPUFF modelling results for atmospheric polycyclic aromatic hydrocarbons (PAHs, alkylated PAHs, and dibenzothiophenes (DBTs, obtained using each of the emissions databases, are presented and compared with measurements from a passive air monitoring network. The JOSM-derived emissions resulted in better model–measurement agreement in the total PAH concentrations and for most PAH species concentrations compared to results using CEMA-derived emissions. At local sites near oil sands mines, the percent error of the model compared to observations decreased from 30 % using the CEMA-derived emissions to 17 % using the JOSM-derived emissions. The improvement at local sites was likely attributed to the inclusion of updated tailings pond emissions estimated from JOSM activities. In either the CEMA-derived or JOSM-derived emissions scenario, the model underestimated PAH concentrations by a factor of 3 at remote locations. Potential reasons for the disagreement include forest fire emissions, re-emissions of previously deposited PAHs, and long-range transport not considered in the model. Alkylated PAH and DBT concentrations were also significantly underestimated. The CALPUFF model is expected to predict higher concentrations because of the limited chemistry and deposition modelling. Thus the model underestimation of PACs is likely due to gaps in the emissions database for these compounds and uncertainties in the methodology for estimating the emissions. Future work is required that focuses on improving the PAC

  9. An optimised set-up for total reflection particle induced X-ray emission

    International Nuclear Information System (INIS)

    Kan, J.A. van; Vis, R.D.

    1997-01-01

    MeV proton beams at small angles of incidence (0-35 mrad) are used to analyse trace elements on flat surfaces such as Si wafers or quartz substrates. In these experiments, the particle induced X-ray emission (PIXE) signal is used in a new optimized set-up. This set-up is constructed in such a way that the X-ray detector can reach very large solid angles, larger than 1 sr. Use of these large detector solid angles, combined with the reduction of bremsstrahlung background, affords limits of detection (LOD) of the order of 10 10 at cm -2 using total reflection particle induced X-ray emission (TPIXE). The LODs from earlier TPIXE measurements in a non-optimized set-up are used to estimate LODs in the new TPIXE set-up. Si wafers with low surface concentrations of V, Ni, Cu and Ag are used as standards to calibrate the LODs found with this set-up. The metal concentrations are determined by total reflection X-ray fluorescence (TXRF). The TPIXE measurements are compared with TXRF measurements on the same wafers. (Author)

  10. Atmospheric polycyclic aromatic hydrocarbons (PAHs) in Asia: A review from 1999 to 2004

    International Nuclear Information System (INIS)

    Chang, K.-F.; Fang, G.-C.; Chen, J.-C.; Wu, Y.-S.

    2006-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are present in both gaseous and particulate phases. These compounds are considered to be atmospheric contaminants and are human carcinogens. Many studies have monitored atmospheric particulate and gaseous phases of PAH in Asia over the past 5 years. This work compares and discusses different sample collection, pretreatment and analytical methods. The main PAH sources are traffic exhausts (AcPy, FL, Flu, PA, Pyr, CHR, BeP) and industrial emissions (BaP, BaA, PER, BeP, COR, CYC). PAH concentrations are highest in areas of traffic, followed by the urban sites, and lowest in rural sites. Meteorological conditions, such as temperature, wind speed and humidity, strongly affect PAH concentrations at all sampling sites. This work elucidates the characteristics, sources and distribution, and the healthy impacts of atmospheric PAH species in Asia. - This work summarizes the characteristics, sources and distribution, and the healthy impacts of atmospheric PAH species in Asia

  11. [Comparison of polycyclic aromatic hydrocarbons (PAHS) contents in bakery products].

    Science.gov (United States)

    Ciemniak, Artur; Witczak, Agata

    2010-01-01

    Polycyclic aromatic hydrocarbons are a group of well-known chemical carcinogens with a wide distribution in the environment and formed by the incomplete combustion of organic substances. PAHs have attracted most attention because of their carcinogenic potential. PAHs have been found as contaminants in different food categories such as dairy products, smoked and barbecued meat, vegetables, fruits, oils, coffee, tea, and cereals. Processing of food at high temperatures increases the amount of PAHs in the food Diet is the major source of human exposure to PAHs. The major dietary source of PAH are oils and fats, cereals products and vegetables. The aims of this study were to determine the content levels of 23 PAHs in various sorts of bread. The analytical procedure was based Soxhlet extraction with n--hexane and cleaned up in aflorisil cartridge. Chromatographic separation was performed using gas chromatography (HP 6890) coupled to mass spectrometry (HP 5973). The total concentration of PAHs was low end varied between 2.61 microg/kg to 43.4 microg/kg. Furthermore, the results revealed differences in concentrations of PAHs between rind and bread-crumb.

  12. Effect of prenatal PAH exposure on birth outcomes and neurocognitive development in a cohort of newborns in Poland. Study design and preliminary ambient data

    Energy Technology Data Exchange (ETDEWEB)

    Jedrychowski, W.; Whyatt, R.M.; Camann, D.E.; Bawle, U.V.; Peki, K.; Spengler, J.D.; Dumyahn, T.S.; Penar, A.; Perera, F.F. [Jagiellonian University, Krakow (Poland). Department of Epidemiology and Preventive Medicine, Collegium Medicum

    2003-07-01

    Preliminary data suggest an association between infant mortality rates and several measures of ambient air pollution, including dustfall and polycyclic aromatic hydrocarbons (PAH). The effects of airborne PAH components on fetal growth and early childhood development are of primary interest since we have previously demonstrated that these pollutants were associated with significant decrements in birth weight, length and head circumference in Polish newborn babies. The undertaken research combines a state-of-the-art environmental monitoring and molecular approaches with comprehensive neurodevelopment assessments. A further innovation is the incorporation of biomarkers (lead and antioxidants in cord blood) to control for potential confounding of exposure-effect. The mean overall concentrations of specific PAH compounds in Krakow, Poland were highest for benzo(b)fluoranthene (23 ng/m{sup 3}), benzo(a)anthracene, indeno(1,2,3-cd)pyrene, chyresene and benzo(a)pyrene. Concentrations of the PAH compounds measured by personal monitoring were higher in residents of the higher polluted area of the city. Comparison between the Krakow and New York City ambient data demonstrates that the concentrations and proportions of specific compounds in the total PAH mixture differ widely across these cities. Thus, one may expect that the PAH-related health risks would differ between the two areas not only because exposures are different, but also because the PAH profile differs. Presumably, this different profile is a consequence of variations in the sources of fossil and solid fuels used to produce energy. In Poland, more coal is used than in New York City. Auto emissions for example, are low in benzo(a)pyrene, whereas such emissions from refuse burning are high. 31 refs.

  13. 3 mm GMVA Observations of Total and Polarized Emission from Blazar and Radio Galaxy Core Regions

    Directory of Open Access Journals (Sweden)

    Carolina Casadio

    2017-10-01

    Full Text Available We present total and linearly polarized 3 mm Global mm-VLBI Array (GMVA; mm-VLBI: Very Long Baseline Interferometry observations at millimetre wavelengths images of a sample of blazars and radio galaxies from the VLBA-BU-BLAZAR 7 mm monitoring program designed to probe the innermost regions of active galactic nuclei (AGN jets and locate the sites of gamma-ray emission observed by the Fermi-LAT. The lower opacity at 3 mm and improved angular resolution—on the order of 50 microarcseconds—allow us to distinguish features in the jet not visible in the 7 mm VLBA data. We also compare two different methods used for the calibration of instrumental polarisation and we analyze the resulting images for some of the sources in the sample.

  14. Distribution and origin sources of Polycyclic Aromatic Hydrocarbons (PAHs) pollution in sediment of Sarawak coastal area

    International Nuclear Information System (INIS)

    Mohd Shuhaimi Elias; Abdul Khalik Wood; Zaleha Hashim; Mohd Suhaimi Hamzah; Shamsiah Abdul Rahman; Nazaratul Ashifa Abdullah Salim

    2010-01-01

    Alkyl and parent Polycyclic Aromatic Hydrocarbons (PAHs) compounds in marine sediment sample collected from ten locations along Sarawak coastal areas were extracted and analyzed by using gas chromatography-mass spectrometry. The source identification of PAH pollution in marine sediment of Sarawak coastal areas were identify by ratios technique of An/ An+phen, Fl/ Fl +Py, B[a]A/ (B[a]A+Chry) and total Methyl Phen/ Phen. The total alkyl and parent PAHs concentration varies from 36.5 - 277.4 ng/ g dry weight (d.w.) with a mean concentration of 138.2 ng/ g d.w. The ratio values of PAHs pollution in marine sediment of Sarawak coastal areas are clearly indicating the PAHs pollutions are originated from petroleum (petrogenic) and petroleum combustion (pyrolytic). However, the origin sources of PAHs pollution in a few stations were uncertain due to mixing sources of PAHs. (author)

  15. Observational Evidence Linking Interstellar UV Absorption to PAH Molecules

    Energy Technology Data Exchange (ETDEWEB)

    Blasberger, Avi; Behar, Ehud; Perets, Hagai B. [Department of Physics, Technion (Israel); Brosch, Noah [The Wise Observatory and School of Physics and Astronomy, Tel Aviv University (Israel); Tielens, Alexander G. G. M. [Leiden Observatory, Leiden University (Netherlands)

    2017-02-20

    The 2175 Å UV extinction feature was discovered in the mid-1960s, yet its physical origin remains poorly understood. One suggestion is absorption by polycyclic aromatic hydrocarbon (PAH) molecules, which is supported by theoretical molecular structure computations and by laboratory experiments. PAHs are positively detected by their 3.3, 6.2, 7.7, 8.6, 11.3, and 12.7 μ m IR emission bands, which are specified by their modes of vibration. A definitive empirical link between the 2175 Å UV extinction and the IR PAH emission bands, however, is still missing. We present a new sample of hot stars that have both 2175 Å absorption and IR PAH emission. We find significant shifts of the central wavelength of the UV absorption feature, up to 2350 Å, but predominantly in stars that also have IR PAH emission. These UV shifts depend on stellar temperature in a fashion that is similar to the shifts of the 6.2 and 7.7 μ m IR PAH bands, that is, the features are increasingly more redshifted as the stellar temperature decreases, but only below ∼15 kK. Above 15 kK both UV and IR features retain their nominal values. Moreover, we find a suggestive correlation between the UV and IR shifts. We hypothesize that these similar dependences of both the UV and IR features on stellar temperature hint at a common origin of the two in PAH molecules and may establish the missing link between the UV and IR observations. We further suggest that the shifts depend on molecular size, and that the critical temperature of ∼15 kK above which no shifts are observed is related to the onset of UV-driven hot-star winds and their associated shocks.

  16. Observational Evidence Linking Interstellar UV Absorption to PAH Molecules

    International Nuclear Information System (INIS)

    Blasberger, Avi; Behar, Ehud; Perets, Hagai B.; Brosch, Noah; Tielens, Alexander G. G. M.

    2017-01-01

    The 2175 Å UV extinction feature was discovered in the mid-1960s, yet its physical origin remains poorly understood. One suggestion is absorption by polycyclic aromatic hydrocarbon (PAH) molecules, which is supported by theoretical molecular structure computations and by laboratory experiments. PAHs are positively detected by their 3.3, 6.2, 7.7, 8.6, 11.3, and 12.7 μ m IR emission bands, which are specified by their modes of vibration. A definitive empirical link between the 2175 Å UV extinction and the IR PAH emission bands, however, is still missing. We present a new sample of hot stars that have both 2175 Å absorption and IR PAH emission. We find significant shifts of the central wavelength of the UV absorption feature, up to 2350 Å, but predominantly in stars that also have IR PAH emission. These UV shifts depend on stellar temperature in a fashion that is similar to the shifts of the 6.2 and 7.7 μ m IR PAH bands, that is, the features are increasingly more redshifted as the stellar temperature decreases, but only below ∼15 kK. Above 15 kK both UV and IR features retain their nominal values. Moreover, we find a suggestive correlation between the UV and IR shifts. We hypothesize that these similar dependences of both the UV and IR features on stellar temperature hint at a common origin of the two in PAH molecules and may establish the missing link between the UV and IR observations. We further suggest that the shifts depend on molecular size, and that the critical temperature of ∼15 kK above which no shifts are observed is related to the onset of UV-driven hot-star winds and their associated shocks.

  17. Polycyclic aromatic hydrocarbons (PAH) formation from the pyrolysis of different municipal solid waste fractions

    International Nuclear Information System (INIS)

    Zhou, Hui; Wu, Chunfei; Onwudili, Jude A.; Meng, Aihong; Zhang, Yanguo; Williams, Paul T.

    2015-01-01

    Highlights: • PAH from pyrolysis of 9 MSW fractions was investigated. • Pyrolysis of plastics released more PAH than that of biomass. • Naphthalene was the most abundant PAH in the tar. • The mechanism of PAH release from biomass and plastics was proposed. - Abstract: The formation of 2–4 ring polycyclic aromatic hydrocarbons (PAH) from the pyrolysis of nine different municipal solid waste fractions (xylan, cellulose, lignin, pectin, starch, polyethylene (PE), polystyrene (PS), polyvinyl chloride (PVC), and polyethylene terephthalate (PET)) were investigated in a fixed bed furnace at 800 °C. The mass distribution of pyrolysis was also reported. The results showed that PS generated the most total PAH, followed by PVC, PET, and lignin. More PAH were detected from the pyrolysis of plastics than the pyrolysis of biomass. In the biomass group, lignin generated more PAH than others. Naphthalene was the most abundant PAH, and the amount of 1-methynaphthalene and 2-methynaphthalene was also notable. Phenanthrene and fluorene were the most abundant 3-ring PAH, while benzo[a]anthracene and chrysene were notable in the tar of PS, PVC, and PET. 2-ring PAH dominated all tar samples, and varied from 40 wt.% to 70 wt.%. For PS, PET and lignin, PAH may be generated directly from the aromatic structure of the feedstock

  18. Polycyclic aromatic hydrocarbons (PAH) formation from the pyrolysis of different municipal solid waste fractions

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Hui [Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084 (China); Energy Research Institute, University of Leeds, Leeds LS2 9JT (United Kingdom); Wu, Chunfei, E-mail: c.wu@leeds.ac.uk [Energy Research Institute, University of Leeds, Leeds LS2 9JT (United Kingdom); Onwudili, Jude A. [Energy Research Institute, University of Leeds, Leeds LS2 9JT (United Kingdom); Meng, Aihong [Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084 (China); Zhang, Yanguo, E-mail: zhangyg@tsinghua.edu.cn [Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084 (China); Williams, Paul T., E-mail: p.t.williams@leeds.ac.uk [Energy Research Institute, University of Leeds, Leeds LS2 9JT (United Kingdom)

    2015-02-15

    Highlights: • PAH from pyrolysis of 9 MSW fractions was investigated. • Pyrolysis of plastics released more PAH than that of biomass. • Naphthalene was the most abundant PAH in the tar. • The mechanism of PAH release from biomass and plastics was proposed. - Abstract: The formation of 2–4 ring polycyclic aromatic hydrocarbons (PAH) from the pyrolysis of nine different municipal solid waste fractions (xylan, cellulose, lignin, pectin, starch, polyethylene (PE), polystyrene (PS), polyvinyl chloride (PVC), and polyethylene terephthalate (PET)) were investigated in a fixed bed furnace at 800 °C. The mass distribution of pyrolysis was also reported. The results showed that PS generated the most total PAH, followed by PVC, PET, and lignin. More PAH were detected from the pyrolysis of plastics than the pyrolysis of biomass. In the biomass group, lignin generated more PAH than others. Naphthalene was the most abundant PAH, and the amount of 1-methynaphthalene and 2-methynaphthalene was also notable. Phenanthrene and fluorene were the most abundant 3-ring PAH, while benzo[a]anthracene and chrysene were notable in the tar of PS, PVC, and PET. 2-ring PAH dominated all tar samples, and varied from 40 wt.% to 70 wt.%. For PS, PET and lignin, PAH may be generated directly from the aromatic structure of the feedstock.

  19. Temporal variability in sediment PAHs accumulation in the northern Gulf of Mexico Shelf

    Science.gov (United States)

    Bam, W.; Maiti, K.; Adhikari, P. L.

    2017-12-01

    Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous group of organic pollutants, some of which are known to be toxic, and/or carcinogenic to humans. The major source of these PAHs into the northern Gulf of Mexico (NGOM) are Mississippi River discharge, coastal erosion, atmospheric deposition, and numerous natural oil seeps and spills. In addition to these background source of PAHs, the Deepwater Horizon (DWH) oil spill in 2010 added 21,000 tons of PAHs into the NGOM water. In this study, we measured PAHs distribution and accumulation rates in coastal sediments near the Mississippi River mouth in 2011 and 2015 to understand the effect of DWH oil spill in PAHs accumulation in coastal sediments. Sediment cores were collected and sliced at 1 cm interval to measure PAHs concentration, and to estimate 210Pb-based sedimentation and the PAHs' accumulation rates. The results showed that the sediment deposition rates in this region varied between 0.5 to 0.9 cm/yr. The results also showed that the concentration of total PAHsPAH43) and their accumulation rates vary between 68 - 100 ng g-1 and 7 - 160 ng cm-2 yr-1, respectively. While the PAHs accumulation rate in coastal sediment varied over the years, there is no significant variation in PAHs accumulation rate before and after the DWH oil spill.

  20. Polycyclic aromatic hydrocarbons (PAHs) in Austin sediments after a ban on pavement sealers

    Energy Technology Data Exchange (ETDEWEB)

    DeMott, R.P.; Gauthier, T.D.; Wiersema, J.M.; Crenson, G. [ENVIRON International, Tampa, FL (USA)

    2010-07-01

    Polycyclic aromatic hydrocarbon (PAH) concentrations were measured in stream sediments collected before and after a municipal ban on the use of coal-tar-based pavement sealers in Austin, Texas. Samples were collected in October 2005, prior to the ban, and again in April, 2008, approximately 2 years after the ban. Differences in total PAH concentrations between samples collected before and after the ban show no net change in PAH levels in Austin stream sediments. Results of hydrocarbon fingerprinting reveal subtle differences in PAH profiles that appear to reflect the effects of weathering rather than a change in PAH sources.

  1. Biomonitoring, status and source risk assessment of polycyclic aromatic hydrocarbons (PAHs) using honeybees, pine tree leaves, and propolis.

    Science.gov (United States)

    Kargar, Navid; Matin, Golnar; Matin, Amir Abbas; Buyukisik, Hasan Baha

    2017-11-01

    In this study, to identify and quantify the sources of airborne polycyclic aromatic hydrocarbons (PAHs), we gathered honeybee, pine tree leaf, and propolis samples to serve as bioindicators from five stations in the village of "Bozkoy" in the Aliaga industrial district of Izmir (Turkey) during April-May 2014. The PAH concentrations which measured by gas chromatography (GC) varied from 261.18 to 553.33 μg kg -1 dry weight (dw) in honeybee samples, 138.57-853.67 μg kg -1 dw in pine leaf samples, and 798.61-2905.53 μg kg -1 dw in propolis samples. The total PAH concentrations can be ranked as follows: propolis > pine leaves > honeybees. The ring sequence pattern was 5 > 3 > 6 > 4 > 2 for honeybees, 5 > 3 > 4 > 6 > 2 for pine leaves, and 5 > 4 > 6 > 3 > 2 for propolis. The diagnostic ratios [fluoranthene/fluoranthene + pyrene], [indeno(1,2,3-c,d)pyrene/indeno(1,2,3-c,d)pyrene + benzo(g,h,i)perylene], and [benzo(a)anthracene/benzo(a)anthracene + chrysene] indicate coal and biomass combustion to be the dominant PAH source in the study area. In biomonitoring studies of airborne PAHs based on honeybees, fluoranthene is considered to be a characteristic PAH compound. Distribution maps with different numbers of PAH rings among the sampling sites show the advantages of honeybee samples as indicators due to the honeybee's provision of a broader range of information with respect to heavier pollutants that are typically not in the gas or suspended phase for long periods of time. Our correlation, factor analysis, and principal components analysis (PCA) results indicate potential sources of PAH pollution in pine leaves and honeybees from airborne emissions, but we found propolis to be contaminated by PAHs due to the replacement of herbal sources of resins with synthetic gummy substances from paving materials (e.g., asphalt and tar leaks). Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Assessment of ecotoxicity and total volatile organic compound (TVOC) emissions from food and children's toy products.

    Science.gov (United States)

    Szczepańska, Natalia; Marć, Mariusz; Kudłak, Błażej; Simeonov, Vasil; Tsakovski, Stefan; Namieśnik, Jacek

    2018-09-30

    The development of new methods for identifying a broad spectrum of analytes, as well as highly selective tools to provide the most accurate information regarding the processes and relationships in the world, has been an area of interest for researchers for many years. The information obtained with these tools provides valuable data to complement existing knowledge but, above all, to identify and determine previously unknown hazards. Recently, attention has been paid to the migration of xenobiotics from the surfaces of various everyday objects and the resulting impacts on human health. Since children are among those most vulnerable to health consequences, one of the main subjects of interest is the migration of low-molecular-weight compounds from toys and products intended for children. This migration has become a stimulus for research aimed at determining the degree of release of compounds from popular commercially available chocolate/toy sets. One of main objectives of this research was to determine the impact of time on the ecotoxicity (with Vibrio fischeri bioluminescent bacteria) of extracts of products intended for children and to assess the correlation with total volatile organic compound emissions using basic chemometric methods. The studies on endocrine potential (with XenoScreen YES/YAS) of the extracts and showed that compounds released from the studied objects (including packaging foils, plastic capsules storing toys, most of toys studied and all chocolate samples) exhibit mostly androgenic antagonistic behavior while using artificial saliva as extraction medium increased the impact observed. The impact of time in most cases was positive one and increased with prolonging extraction time. The small-scale stationary environmental test chambers - μ-CTE™ 250 system was employed to perform the studies aimed at determining the profile of total volatile organic compounds (TVOCs) emissions. Due to this it was possible to state that objects from which the

  3. Biodegradation of Mixed PAHs by PAH-Degrading Endophytic Bacteria

    Directory of Open Access Journals (Sweden)

    Xuezhu Zhu

    2016-08-01

    Full Text Available Endophytic bacteria can promote plant growth, induce plant defence mechanisms, and increase plant resistance to organic contaminants. The aims of the present study were to isolate highly PAH-degrading endophytic bacteria from plants growing at PAH-contaminated sites and to evaluate the capabilities of these bacteria to degrade polycyclic aromatic hydrocarbons (PAHs in vitro, which will be beneficial for re-colonizing target plants and reducing plant PAH residues through the inoculation of plants with endophytic bacteria. Two endophytic bacterial strains P1 (Stenotrophomonas sp. and P3 (Pseudomonas sp., which degraded more than 90% of phenanthrene (PHE within 7 days, were isolated from Conyza canadensis and Trifolium pretense L., respectively. Both strains could use naphthalene (NAP, PHE, fluorene (FLR, pyrene (PYR, and benzo(apyrene (B(aP as the sole sources of carbon and energy. Moreover, these bacteria reduced the contamination of mixed PAHs at high levels after inoculation for 7 days; strain P1 degraded 98.0% NAP, 83.1% FLR, 87.8% PHE, 14.4% PYR, and 1.6% B(aP, and strain P3 degraded 95.3% NAP, 87.9% FLR, 90.4% PHE, 6.9% PYR, and negligible B(aP. Notably, the biodegradation of PAHs could be promoted through additional carbon and nitrogen nutrients; therein, beef extract was suggested as the optimal co-substrate for the degradation of PAHs by these two strains (99.1% PHE was degraded within 7 days. Compared with strain P1, strain P3 has more potential for the use in the removal of PAHs from plant tissues. These results provide a novel perspective in the reduction of plant PAH residues in PAH-contaminated sites through inoculating plants with highly PAH-degrading endophytic bacteria.

  4. Polycyclic aromatic hydrocarbons (PAH) in exhaust emissions from diesel engines powered by rapeseed oil methylester and heated non-esterified rapeseed oil

    Czech Academy of Sciences Publication Activity Database

    Vojtíšek-Lom, M.; Czerwinski, J.; Leníček, J.; Sekyra, M.; Topinka, Jan

    2012-01-01

    Roč. 60, 14 JUNE (2012), s. 253-261 ISSN 1352-2310 R&D Projects: GA ČR GAP503/11/0142 Grant - others:GA ČR(CZ) GA101/08/1717; GA MŠk(CZ) 1M0568; project MEDETOX(XE) LIFE10ENV/CZ/651 Institutional research plan: CEZ:AV0Z50390703 Institutional support: RVO:68378041 Keywords : diesel engine * diesel emissions * particulate matter Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 3.110, year: 2012

  5. Recent Advances in Laboratory Infrared Spectroscopy of Polycyclic Aromatic Hydrocarbons: PAHs in the Far Infrared

    Science.gov (United States)

    Mattioda, Andrew L.; Ricca, Alessandra; Tucker, Jonathan; Boersma, Christiaan; Bauschlicher, Charles, Jr.; Allamandola, Louis J.

    2010-01-01

    Over 25 years of observations and laboratory work have shown that the mid-IR spectra of a majority of astronomical sources are dominated by emission features near 3.3, 6.2, 7.7, and 11.2 microns, which originate in free polycyclic aromatic hydrocarbon (PAH) molecules. PAHs dominate the mid-IR emission from many galactic and extragalactic objects. As such, this material tracks a wide variety of astronomical processes, making this spectrum a powerful probe of the cosmos Apart from bands in the mid-IR, PAHs have bands spanning the Far-IR (FIR) and emission from these FIR features should be present in astronomical sources showing the Mid-IR PAH bands. However, with one exception, the FIR spectral characteristics are known only for a few neutral small PAHs trapped in salt pellets or oils at room temperature, data which is not relevant to astrophysics. Furthermore, since most emitting PAHs responsible for the mid-IR astronomical features are ionized, the absence of any experimental or theoretical PAH ion FIR spectra will make it impossible to correctly interpret the FIR data from these objects. In view of the upcoming Herschel space telescope mission and SOFIA's FIR airborne instrumentation, which will pioneer the FIR region, it is now urgent to obtain PAH FIR spectra. This talk will present an overview recent advances in the laboratory spectroscopy of PAHs, Highlighting the FIR spectroscopy along with some quantum calculations.

  6. Polynuclear aromatic hydrocarbons (PAHs) mediate cadmium toxicity to an emergent wetland species

    International Nuclear Information System (INIS)

    Zhang, Zhenhua; Rengel, Zed; Meney, Kathy; Pantelic, Ljiljana; Tomanovic, Radmila

    2011-01-01

    Growth and pollutant removal by emergent wetland plants may be influenced by interactions among mixed pollutants in constructed wetlands. A glasshouse experiment was conducted to investigate interactive effects of cadmium (Cd) x polynuclear aromatic hydrocarbons (PAHs) x plant treatments on growth of Juncus subsecundus, Cd and PAH removal from soil and the total number of microorganisms in soil. Growth and biomass of J. subsecundus were significantly influenced by interaction of Cd and PAHs, significantly decreasing with either Cd or PAH additions, but with the effect of Cd on plant growth being stronger than that of PAHs. The mixture of low Cd and low PAH lessened Cd toxicity to plants, resulting in improved plant growth and increased Cd accumulation in plant tissues, thus enhancing Cd removal by plants. The dissipation of PAHs in soils was significantly influenced by interactions of Cd, PAH and plant presence or absence. The total number of microorganisms in soils was significantly increased by the PAH additions. The interactive effect of Cd and PAHs on plant growth may be linked to the changes in the abundance of microorganisms in the rhizosphere, probably via a positive effect of PAH metabolites and/or phytohormones produced by microorganisms on plant growth.

  7. Spatial Distribution of Polycyclic Aromatic Hydrocarbon (PAH) Concentrations in Soils from Bursa, Turkey.

    Science.gov (United States)

    Karaca, Gizem

    2016-02-01

    The objectives of this study were to identify regional variations in soil polycyclic aromatic hydrocarbon (PAH) contamination in Bursa, Turkey, and to determine the distributions and sources of various PAH species and their possible sources. Surface soil samples were collected from 20 different locations. The PAH concentrations in soil samples were analyzed using gas chromatography-mass spectrometry (GC-MS). The total PAH concentrations (∑12 PAH) varied spatially between 8 and 4970 ng/g dry matter (DM). The highest concentrations were measured in soils taken from traffic+barbecue+ residential areas (4970 ng/g DM) and areas with cement (4382 ng/g DM) and iron-steel (4000 ng/g DM) factories. In addition, the amounts of ∑7 carcinogenic PAH ranged from 1 to 3684 ng/g DM, and between 5 and 74 % of the total PAHs consisted of such compounds. Overall, 4-ring PAH compounds (Fl, Pyr, BaA and Chr) were dominant in the soil samples, with 29-82 % of the ∑12 PAH consisting of 4-ring PAH compounds. The ∑12 BaPeq values ranged from 0.1 to 381.8 ng/g DM. Following an evaluation of the molecular diagnostic ratios, it was concluded that the PAH pollution in Bursa soil was related to pyrolytic sources; however, the impact of petrogenic sources should not be ignored.

  8. Distribution of polycyclic aromatic hydrocarbons (PAHs) in rivers and estuaries in Malaysia: a widespread input of petrogenic PAHs.

    Science.gov (United States)

    Zakaria, Mohamad Pauzi; Takada, Hideshige; Tsutsumi, Shinobu; Ohno, Kei; Yamada, Junya; Kouno, Eriko; Kumata, Hidetoshi

    2002-05-01

    This is the first publication on the distribution and sources of polycyclic aromatic hydrocarbons (PAHs) in riverine and coastal sediments in South East Asia where the rapid transfer of land-based pollutants into aquatic environments by heavy rainfall and runoff waters is of great concern. Twenty-nine Malaysian riverine and coastal sediments were analyzed for PAHs (3-7 rings) by gas chromatography mass spectrometry. Total PAHs concentrations in the sediment ranged from 4 to 924 ng/g. Alkylated homologues were abundant for all sediment samples. The ratio of the sum of methylphenanthrenes to phenanthrene (MP/P), an index of petrogenic PAHs contribution, was more than unity for 26 sediment samples and more than 3 for seven samples for urban rivers covering a broad range of locations. The MP/P ratio showed a strong correlation with the total PAHs concentrations, with an r2 value of 0.74. This ratio and all other compositional features indicated that Malaysian urban sediments are heavily impacted by petrogenic PAHs. This finding is in contrast to other studies reported in many industrialized countries where PAHs are mostly of pyrogenic origin. The MP/P ratio was also significantly correlated with higher molecular weight PAHs such as benzo[a]pyrene, suggesting unique PAHs source in Malaysia which contains both petrogenic PAHs and pyrogenic PAHs. PAHs and hopanes fingerprints indicated that used crankcase oil is one of the major contributors of the sedimentary PAHs. Two major routes of inputs to aquatic environments have been identified: (1) spillage and dumping of waste crankcase oil and (2) leakage of crankcase oils from vehicles onto road surfaces, with the subsequent washout by street runoff. N-Cyclohexyl-2-benzothiazolamine (NCBA), a molecular marker of street dust, was detected in the polluted sediments. NCBA and other biomarker profiles confirmed our hypothesis of the input from street dust contained the leaked crankcase oil. The fingerprints excluded crude oil

  9. Biomonitoring airborne parent and alkylated three-ring PAHs in the Greater Cologne Conurbation I: Temporal accumulation patterns

    International Nuclear Information System (INIS)

    Lehndorff, E.; Schwark, L.

    2009-01-01

    Polycyclic aromatic hydrocarbons (PAHs) comprise an important group of air pollutants, with three-ring components (PAH-3) often dominating. Spatiotemporal variation in atmospheric PAH-3 can be analyzed by biomonitoring but high vapour pressure and low octanol-air-partitioning of PAH-3 cause dynamic accumulation on plant surfaces. This study for the first time shows that PAH-3 exhibit systematic accumulation trends on pine needles of 3-48 months of exposure time at six sites in Germany. Correlation of needle exposure time with PAH-3 concentration was r 2 = 0.83 for phenanthrene and methylphenanthrenes, r 2 = 0.77 for cyclopenta[def]phenanthrene, r 2 = 0.60 for dibenzothiophene, r 2 = 0.57 for dimethylphenanthrenes and r 2 = 0.32 for retene. Variations in PAH-3 for summer and winter collected needles emphasize vegetation-air-partitioning influence on cumulative PAH-3 loads. PAH-3 ratios calculated for needle cohorts indicate persistence of original PAH patterns thus demonstrating the source-diagnostic potential of pine needle biomonitoring, which is utilized in part II of this study where spatial distribution of PAH-3 is investigated and related to emission sources. - Accumulation of volatile three-ring PAHs on pine needles was found to be systematic over a period of 50 months thus qualifying PAHs for regional air quality studies

  10. Biomonitoring airborne parent and alkylated three-ring PAHs in the Greater Cologne Conurbation I: Temporal accumulation patterns

    Energy Technology Data Exchange (ETDEWEB)

    Lehndorff, E. [Department of Geology and Mineralogy, University of Cologne, Zuelpicher Str. 49a, 50674 Cologne (Germany); Schwark, L. [Department of Geology and Mineralogy, University of Cologne, Zuelpicher Str. 49a, 50674 Cologne (Germany); Institute of Geosciences, Kiel University, Ludewig-Meyn-Str. 10, 24118 Kiel (Germany)], E-mail: ls@gpi.uni-kiel.de

    2009-04-15

    Polycyclic aromatic hydrocarbons (PAHs) comprise an important group of air pollutants, with three-ring components (PAH-3) often dominating. Spatiotemporal variation in atmospheric PAH-3 can be analyzed by biomonitoring but high vapour pressure and low octanol-air-partitioning of PAH-3 cause dynamic accumulation on plant surfaces. This study for the first time shows that PAH-3 exhibit systematic accumulation trends on pine needles of 3-48 months of exposure time at six sites in Germany. Correlation of needle exposure time with PAH-3 concentration was r{sup 2} = 0.83 for phenanthrene and methylphenanthrenes, r{sup 2} = 0.77 for cyclopenta[def]phenanthrene, r{sup 2} = 0.60 for dibenzothiophene, r{sup 2} = 0.57 for dimethylphenanthrenes and r{sup 2} = 0.32 for retene. Variations in PAH-3 for summer and winter collected needles emphasize vegetation-air-partitioning influence on cumulative PAH-3 loads. PAH-3 ratios calculated for needle cohorts indicate persistence of original PAH patterns thus demonstrating the source-diagnostic potential of pine needle biomonitoring, which is utilized in part II of this study where spatial distribution of PAH-3 is investigated and related to emission sources. - Accumulation of volatile three-ring PAHs on pine needles was found to be systematic over a period of 50 months thus qualifying PAHs for regional air quality studies.

  11. The formation of aromatics and PAH's in laminar flames

    International Nuclear Information System (INIS)

    Marinov, N M; Pitz, W J; Westbrook, C K

    1999-01-01

    The formation of aromatics and PAH's is an important problem in combustion. These compounds are believed to contribute to the formation of soot whose emission from diesel engines is regulated widely throughout the industrial world. Additionally, the United States Environmental Protection Agency regulates the emission of many aromatics and PAH species from stationary industrial burners, under the 1990 Clean Air Act Amendments. The above emission regulations have created much interest in understanding how these species are formed in combustion systems. Much previous work has been done on aromatics and PAH's. The work is too extensive to review here, but is reviewed in Reference 1. A few recent developments are highlighted here. McEnally, Pfefferle and coworkers have studied aromatic, PAH and soot formation in a variety of non-premixed flames with hydrocarbon additives[2-4]. They found additives that contain a C5 ring increase the concentration of aromatics and soot[4]. Howard and coworkers have studied the formation of aromatic and PAH's in low pressure, premixed, laminar hydrocarbon flames. They found the cyclopentadienyl radical to be a key species in naphthalene formation in a fuel-rich, benzene/Ar/O2 flame[5

  12. Generation and distribution of PAHs in the process of medical waste incineration

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Ying, E-mail: echochen327@163.com [School of Environment, Tsinghua University, Beijing 100084 (China); National Center of Solid Waste Management, Ministry of Environmental Protection, Beijing 100029 (China); Zhao, Rongzhi [Civil and Environmental Engineering School, University of Science and Technology Beijing, Beijing 100083 (China); Xue, Jun [National Center of Solid Waste Management, Ministry of Environmental Protection, Beijing 100029 (China); Li, Jinhui, E-mail: jinhui@tsinghua.edu.cn [State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084 (China)

    2013-05-15

    Highlights: ► PAHs generation and distribution features of medical waste incineration are studied. ► More PAHs were found in fly ash than that in bottom ash. ► The highest proportion of PAHs consisted of the seven most carcinogenic ones. ► Increase of free oxygen molecule and burning temperature promote PAHs degradation. ► There is a moderate positive correlation between total PCDD/Fs and total PAHs. - Abstract: After the deadly earthquake on May 12, 2008 in Wenchuan county of China, several different incineration approaches were used for medical waste disposal. This paper investigates the generation properties of polycyclic aromatic hydrocarbons (PAHs) during the incineration. Samples were collected from the bottom ash in an open burning slash site, surface soil at the open burning site, bottom ash from a simple incinerator, bottom ash generated from the municipal solid waste (MSW) incinerator used for medical waste disposal, and bottom ash and fly ash from an incinerator exclusively used for medical waste. The species of PAHs were analyzed, and the toxicity equivalency quantities (TEQs) of samples calculated. Analysis results indicate that the content of total PAHs in fly ash was 1.8 × 10{sup 3} times higher than that in bottom ash, and that the strongly carcinogenic PAHs with four or more rings accumulated sensitively in fly ash. The test results of samples gathered from open burning site demonstrate that Acenaphthylene (ACY), Acenaphthene (ACE), Fluorene (FLU), Phenanthrene (PHE), Anthracene (ANT) and other PAHs were inclined to migrate into surrounding environment along air and surface watershed corridors, while 4- to 6-ring PAHs accumulated more likely in soil. Being consistent with other studies, it has also been confirmed that increases in both free oxygen molecules and combustion temperatures could promote the decomposition of polycyclic PAHs. In addition, without the influence of combustion conditions, there is a positive correlation between

  13. Generation and distribution of PAHs in the process of medical waste incineration

    International Nuclear Information System (INIS)

    Chen, Ying; Zhao, Rongzhi; Xue, Jun; Li, Jinhui

    2013-01-01

    Highlights: ► PAHs generation and distribution features of medical waste incineration are studied. ► More PAHs were found in fly ash than that in bottom ash. ► The highest proportion of PAHs consisted of the seven most carcinogenic ones. ► Increase of free oxygen molecule and burning temperature promote PAHs degradation. ► There is a moderate positive correlation between total PCDD/Fs and total PAHs. - Abstract: After the deadly earthquake on May 12, 2008 in Wenchuan county of China, several different incineration approaches were used for medical waste disposal. This paper investigates the generation properties of polycyclic aromatic hydrocarbons (PAHs) during the incineration. Samples were collected from the bottom ash in an open burning slash site, surface soil at the open burning site, bottom ash from a simple incinerator, bottom ash generated from the municipal solid waste (MSW) incinerator used for medical waste disposal, and bottom ash and fly ash from an incinerator exclusively used for medical waste. The species of PAHs were analyzed, and the toxicity equivalency quantities (TEQs) of samples calculated. Analysis results indicate that the content of total PAHs in fly ash was 1.8 × 10 3 times higher than that in bottom ash, and that the strongly carcinogenic PAHs with four or more rings accumulated sensitively in fly ash. The test results of samples gathered from open burning site demonstrate that Acenaphthylene (ACY), Acenaphthene (ACE), Fluorene (FLU), Phenanthrene (PHE), Anthracene (ANT) and other PAHs were inclined to migrate into surrounding environment along air and surface watershed corridors, while 4- to 6-ring PAHs accumulated more likely in soil. Being consistent with other studies, it has also been confirmed that increases in both free oxygen molecules and combustion temperatures could promote the decomposition of polycyclic PAHs. In addition, without the influence of combustion conditions, there is a positive correlation between total

  14. Toxic emissions from mobile sources: a total fuel-cycle analysis for conventional and alternative fuel vehicles.

    Science.gov (United States)

    Winebrake, J J; Wang, M Q; He, D

    2001-07-01

    Mobile sources are among the largest contributors of four hazardous air pollutants--benzene, 1,3-butadiene, acetaldehyde, and formaldehyde--in urban areas. At the same time, federal and state governments are promoting the use of alternative fuel vehicles as a means to curb local air pollution. As yet, the impact of this movement toward alternative fuels with respect to toxic emissions has not been well studied. The purpose of this paper is to compare toxic emissions from vehicles operating on a variety of fuels, including reformulated gasoline (RFG), natural gas, ethanol, methanol, liquid petroleum gas (LPG), and electricity. This study uses a version of Argonne National Laboratory's Greenhouse Gas, Regulated Emissions, and Energy Use in Transportation (GREET) model, appropriately modified to estimate toxic emissions. The GREET model conducts a total fuel-cycle analysis that calculates emissions from both downstream (e.g., operation of the vehicle) and upstream (e.g., fuel production and distribution) stages of the fuel cycle. We find that almost all of the fuels studied reduce 1,3-butadiene emissions compared with conventional gasoline (CG). However, the use of ethanol in E85 (fuel made with 85% ethanol) or RFG leads to increased acetaldehyde emissions, and the use of methanol, ethanol, and compressed natural gas (CNG) may result in increased formaldehyde emissions. When the modeling results for the four air toxics are considered together with their cancer risk factors, all the fuels and vehicle technologies show air toxic emission reduction benefits.

  15. An interior-point method for total variation regularized positron emission tomography image reconstruction

    Science.gov (United States)

    Bai, Bing

    2012-03-01

    There has been a lot of work on total variation (TV) regularized tomographic image reconstruction recently. Many of them use gradient-based optimization algorithms with a differentiable approximation of the TV functional. In this paper we apply TV regularization in Positron Emission Tomography (PET) image reconstruction. We reconstruct the PET image in a Bayesian framework, using Poisson noise model and TV prior functional. The original optimization problem is transformed to an equivalent problem with inequality constraints by adding auxiliary variables. Then we use an interior point method with logarithmic barrier functions to solve the constrained optimization problem. In this method, a series of points approaching the solution from inside the feasible region are found by solving a sequence of subproblems characterized by an increasing positive parameter. We use preconditioned conjugate gradient (PCG) algorithm to solve the subproblems directly. The nonnegativity constraint is enforced by bend line search. The exact expression of the TV functional is used in our calculations. Simulation results show that the algorithm converges fast and the convergence is insensitive to the values of the regularization and reconstruction parameters.

  16. Polycyclic Aromatic Hydrocarbons (PAHs) and their Bioaccessibility in Meat: a Tool for Assessing Human Cancer Risk.

    Science.gov (United States)

    Hamidi, Elliyana Nadia; Hajeb, Parvaneh; Selamat, Jinap; Abdull Razis, Ahmad Faizal

    2016-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are primarily formed as a result of thermal treatment of food, especially barbecuing or grilling. Contamination by PAHs is due to generation by direct pyrolysis of food nutrients and deposition from smoke produced through incomplete combustion of thermal agents. PAHs are ubiquitous compounds, well-known to be carcinogenic, which can reach the food in different ways. As an important human exposure pathway of contaminants, dietary intake of PAHs is of increasing concern for assessing cancer risk in the human body. In addition, the risks associated with consumption of barbecued meat may increase if consumers use cooking practices that enhance the concentrations of contaminants and their bioaccessibility. Since total PAHs always overestimate the actual amount that is available for absorption by the body, bioaccessibility of PAHs is to be preferred. Bioaccessibility of PAHs in food is the fraction of PAHs mobilized from food matrices during gastrointestinal digestion. An in vitro human digestion model was chosen for assessing the bioaccessibility of PAHs in food as it offers a simple, rapid, low cost alternative to human and animal studies; providing insights which may not be achievable in in vivo studies. Thus, this review aimed not only to provide an overview of general aspects of PAHs such as the formation, carcinogenicity, sources, occurrence, and factors affecting PAH concentrations, but also to enhance understanding of bioaccessibility assessment using an in vitro digestion model.

  17. Emission inventory for fugitive emissions from fuel in Denmark

    DEFF Research Database (Denmark)

    Plejdrup, Marlene Schmidt; Nielsen, Ole-Kenneth; Nielsen, Malene

    This report presents the methodology and data used in the Danish inventory of fugitive emissions from fuels for the years until 2013. The inventory of fugitive emissions includes CO2, CH4, N2O, SO2, NOx, NMVOC, CO, particulate matter, Black carbon, heavy metals, dioxin and PAHs. In 2013 the total...... Danish emission of greenhouse gasses was 54 584 Gg CO2 equivalents. Fugitive emissions from fuels account for 387 Gg CO2 equivalents or approximately 1 %. The major part of the fugitive emissions are emitted as CO2 (61 %) mainly from flaring in upstream oil and gas production. The major source...... of fugitive CH4 emission is production of oil and gas in the North Sea, refining of oil and loading of oil onto ships both offshore and onshore. The fugitive emissions of NMVOC originate for the major part from oil and gas production, loading of ships, transmission and distribution of oil, and to a less...

  18. Short Communication: Emission of Oxygenated Polycyclic Aromatic Hydrocarbons from Biomass Pellet Burning in a Modern Burner for Cooking in China.

    Science.gov (United States)

    Shen, Guofeng; Wei, Siye; Zhang, Yanyan; Wang, Rong; Wang, Bin; Li, Wei; Shen, Huizhong; Huang, Ye; Chen, Yuanchen; Chen, Han; Wei, Wen; Tao, Shu

    2012-12-01

    Biomass pellets are undergoing fast deployment widely in the world, including China. To this stage, there were limited studies on the emissions of various organic pollutants from the burning of those pellets. In addition to parent polycyclic aromatic hydrocarbons, oxygenated PAHs (oPAHs) have been received increased concerns. In this study, emission factors of oPAHs (EF oPAHs ) were measured for two types of pellets made from corn straw and pine wood, respectively. Two combustion modes with (mode II) and without (mode I) secondary side air supply in a modern pellet burner were investigated. For the purpose of comparison, EF oPAHs for raw fuels combusted in a traditional cooking stove were also measured. EF oPAHs were 348±305 and 396±387 µg/kg in the combustion mode II for pine wood and corn straw pellets, respectively. In mode I, measured EF oPAHs were 77.7±49.4 and 189±118 µg/kg, respectively. EFs in mode II were higher (2-5 times) than those in mode I mainly due to the decreased combustion temperature under more excess air. Compared to EF oPAHs for raw corn straw and pine wood burned in a traditional cooking stove, total EF oPAHs for the pellets in mode I were significantly lower ( p < 0.05 ), likely due to increased combustion efficiencies and change in fuel properties. However, the difference between raw biomass fuels and the pellets burned in mode II was not statistically significant. Taking both the increased thermal efficiencies and decreased EFs into consideration, substantial reduction in oPAH emission can be expected if the biomass pellets can be extensively used by rural residents.

  19. Emission of oxygenated polycyclic aromatic hydrocarbons from biomass pellet burning in a modern burner for cooking in China

    Science.gov (United States)

    Shen, Guofeng; Wei, Siye; Zhang, Yanyan; Wang, Rong; Wang, Bin; Li, Wei; Shen, Huizhong; Huang, Ye; Chen, Yuanchen; Chen, Han; Wei, Wen; Tao, Shu

    2012-12-01

    Biomass pellets are undergoing fast deployment widely in the world, including China. To this stage, there were limited studies on the emissions of various organic pollutants from the burning of those pellets. In addition to parent polycyclic aromatic hydrocarbons, oxygenated PAHs (oPAHs) have been received increased concerns. In this study, emission factors of oPAHs (EFoPAHs) were measured for two types of pellets made from corn straw and pine wood, respectively. Two combustion modes with (mode II) and without (mode I) secondary side air supply in a modern pellet burner were investigated. For the purpose of comparison, EFoPAHs for raw fuels combusted in a traditional cooking stove were also measured. EFoPAHs were 348 ± 305 and 396 ± 387 μg kg-1 in the combustion mode II for pine wood and corn straw pellets, respectively. In mode I, measured EFoPAHs were 77.7 ± 49.4 and 189 ± 118 μg kg-1, respectively. EFs in mode II were higher (2-5 times) than those in mode I mainly due to the decreased combustion temperature under more excess air. Compared to EFoPAHs for raw corn straw and pine wood burned in a traditional cooking stove, total EFoPAHs for the pellets in mode I were significantly lower (p pellets burned in mode II was not statistically significant. Taking both the increased thermal efficiencies and decreased EFs into consideration, substantial reduction in oPAH emission can be expected if the biomass pellets can be extensively used by rural residents.

  20. Influence of Air Pollution and Soil Contamination on the Contents of Polycyclic Aromatic Hydrocarbons (PAHs in Vegetables Grown in Urban Gardens of Sao Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Luís F. Amato-Lourenco

    2017-11-01

    Full Text Available Urban community gardens (UCGs have become prevalent worldwide and play a significant role in strengthening the sustainability of urban food systems. Although UCGs provide multiple benefits to society, the extent to which vegetables grown in them are contaminated by chemical compounds derived from airborne fallout or soil contamination is unclear. We evaluated the influence of both air pollution and the contamination of garden soil beds on the contents of 16 PAHs in the edible tissues of spinach and collard green. The PAH contents were quantified using gas chromatography-mass spectrometry (GC-MS-EI. The concentrations of PAHs in both the vegetables grown in the vessels and in the soil of the UCGs were <0.1 μg kg−1. The total concentrations of the 16 priority PAHs in the soil beds ranged from 132.94 to 410.50 μg kg−1. These levels were lower than those that have been reported from other urban areas. Principal Component Analysis resulted in two components indicating that traffic-derived emissions are the main sources of PAHs in the soil. The first component represented the compounds with higher molecular weights and had a moderate loading for the fine fraction of the soil (clay (0.63. The second component showed a high loading for silt (0.97, including those PAHs with lower molecular weights. Our data show that spinach and collard greens do not accumulate significant PAH concentrations on their leaves over 45-day periods, whether they are raised in controlled soil or in local beds.

  1. Inhalation exposure and risk of polycyclic aromatic hydrocarbons (PAHs) among the rural population adopting wood gasifier stoves compared to different fuel-stove users

    Science.gov (United States)

    Lin, Nan; Chen, Yuanchen; Du, Wei; Shen, Guofeng; Zhu, Xi; Huang, Tianbo; Wang, Xilong; Cheng, Hefa; Liu, Junfeng; Xue, Chunyu; Liu, Guangqing; Zeng, Eddy Y.; Xing, Baoshan; Tao, Shu

    2016-12-01

    Polycyclic aromatica hydrocarbons (PAHs) are a group of compounds with carcinogenic potentials and residential solid fuel combustion is one major source of PAHs in most developing countries. Replacement of traditional stoves with improved ones is believed to be a practical approach to reduce pollutant emissions, however, field assessments on the performance and consequent impacts on air quality and human health after adopting improved stoves are rare. The study is the first time to quantify inhalation exposure to PAHs among the residents who adopted wood gasifier stoves. The results were compared to those still burning coals in the region and compared to exposure levels for different fuel/stove users in literature. The results showed that the PAHs exposure levels for the wood gasifier stove users were significantly lower than the values for those using traditional wood stoves reported in literature, and the daily exposure concentrations of BaPeq (Benzo[a]pyrene equivalent concentration) can be reduced by 48%-91% if traditional wood stoves were replaced by wood gasifier stoves. The corresponding Incremental Lifetime Cancer Risk (ILCR) decreased approximately four times from 1.94 × 10-4 to 5.17 × 10-5. The average concentration of the total 26 PAHs for the wood users was 1091 ± 722 ng/m3, which was comparable to 1060 ± 927 ng/m3 for those using anthracite coals, but the composition profiles were considerably different. The average BaPeq were 116 and 25.8 ng/m3 for the wood and coal users, respectively, and the corresponding ILCR of the anthracite coal users was 1.69 × 10-5, which was nearly one third of those using the wood gasifier stoves. The wood users exposed to not only high levels of high molecular weight PAHs, but relatively high fractions of particulate phase PAHs in small particles compared to the coal users, resulting in high exposure risks.

  2. Quantifying the relative contribution of natural gas fugitive emissions to total methane emissions in Colorado, Utah, and Texas using mobile isotopic methane analysis based on Cavity Ringdown Spectroscopy

    Science.gov (United States)

    Rella, Chris; Winkler, Renato; Sweeney, Colm; Karion, Anna; Petron, Gabrielle; Crosson, Eric

    2014-05-01

    Fugitive emissions of methane into the atmosphere are a major concern facing the natural gas production industry. Because methane is more energy-rich than coal per kg of carbon dioxide emitted into the atmosphere, it represents an attractive alternative to coal for electricity generation, provided that the fugitive emissions of methane are kept under control. A key step in assessing these emissions in a given region is partitioning the observed methane emissions between natural gas fugitive emissions and other sources of methane, such as from landfills or agricultural activities. One effective method for assessing the contribution of these different sources is stable isotope analysis, using the isotopic carbon signature to distinguish between natural gas and landfills or ruminants. We present measurements of methane using a mobile spectroscopic stable isotope analyzer based on cavity ringdown spectroscopy, in three intense natural gas producing regions of the United States: the Denver-Julesburg basin in Colorado, the Uintah basin in Utah, and the Barnett Shale in Texas. Performance of the CRDS isotope analyzer is presented, including precision, calibration, stability, and the potential for measurement bias due to other atmospheric constituents. Mobile isotope measurements of individual sources and in the nocturnal boundary layer have been combined to establish the fraction of the observed methane emissions that can be attributed to natural gas activities. The fraction of total methane emissions in the Denver-Julesburg basin attributed to natural gas emissions is 78 +/- 13%. In the Uinta basin, which has no other significant sources of methane, the fraction is 96% +/- 15%. In addition, results from the Barnett shale are presented, which includes a major urban center (Dallas / Ft. Worth). Methane emissions in this region are spatially highly heterogeneous. Spatially-resolved isotope and concentration measurements are interpreted using a simple emissions model to

  3. A regional mass balance model based on total ammoniacal nitrogen for estimating ammonia emissions from beef cattle in Alberta Canada

    Science.gov (United States)

    Chai, Lilong; Kröbel, Roland; Janzen, H. Henry; Beauchemin, Karen A.; McGinn, Sean M.; Bittman, Shabtai; Atia, Atta; Edeogu, Ike; MacDonald, Douglas; Dong, Ruilan

    2014-08-01

    Animal feeding operations are primary contributors of anthropogenic ammonia (NH3) emissions in North America and Europe. Mathematical modeling of NH3 volatilization from each stage of livestock manure management allows comprehensive quantitative estimates of emission sources and nutrient losses. A regionally-specific mass balance model based on total ammoniacal nitrogen (TAN) content in animal manure was developed for estimating NH3 emissions from beef farming operations in western Canada. Total N excretion in urine and feces was estimated from animal diet composition, feed dry matter intake and N utilization for beef cattle categories and production stages. Mineralization of organic N, immobilization of TAN, nitrification, and denitrification of N compounds in manure, were incorporated into the model to account for quantities of TAN at each stage of manure handling. Ammonia emission factors were specified for different animal housing (feedlots, barns), grazing, manure storage (including composting and stockpiling) and land spreading (tilled and untilled land), and were modified for temperature. The model computed NH3 emissions from all beef cattle sub-classes including cows, calves, breeding bulls, steers for slaughter, and heifers for slaughter and replacement. Estimated NH3 emissions were about 1.11 × 105 Mg NH3 in Alberta in 2006, with a mean of 18.5 kg animal-1 yr-1 (15.2 kg NH3-N animal-1 yr-1) which is 23.5% of the annual N intake of beef cattle (64.7 kg animal-1 yr-1). The percentage of N intake volatilized as NH3-N was 50% for steers and heifers for slaughter, and between 11 and 14% for all other categories. Steers and heifers for slaughter were the two largest contributors (3.5 × 104 and 3.9 × 104 Mg, respectively) at 31.5 and 32.7% of total NH3 emissions because most growing animals were finished in feedlots. Animal housing and grazing contributed roughly 63% of the total NH3 emissions (feedlots, barns and pastures contributed 54.4, 0.2 and 8.1% of

  4. Effects of biodiesel on emissions of regulated air pollutants and polycyclic aromatic hydrocarbons under engine durability testing

    International Nuclear Information System (INIS)

    Hsi-Hsien Yang; Shu-Mei Chien; Mei-Yu Lo; John Chi-Wei Lan; Wen-Chang Lu; Yong-Yuan Ku

    2007-01-01

    An 80,000-km durability test was performed on two engines using diesel and biodiesel (methyl ester of waste cooking oil) as fuel in order to examine emissions resulting from the use of biodiesel. The test biodiesel (B20) was blended with 80% diesel and 20% methyl ester derived from waste cooking oil. Emissions of regulated air pollutants, including CO, HC, NO x , particulate matter (PM) and polycyclic aromatic hydrocarbons (PAHs) were measured at 20,000-km intervals. The identical-model engines were installed on a standard dynamometer equipped with a dilution tunnel used to measure the pollutants. To simulate real-world driving conditions, emission measurements were made in accordance with the United States Environmental Protection Agency (USEPA) FTP transient cycle guidelines. At 0 km of the durability test, HC, CO and PM emission levels were lower for the B20 engine than those for diesel. After running for 20,000 km and longer, they were higher. However, the deterioration coefficients for these regulated air pollutants were not statistically higher than 1.0, implying that the emission factors do not increase significantly after 80,000 km of driving. Total (gaseous+particulate phase) PAH emission levels for both B20 and diesel decreased as the driving mileage accumulated. However, for the engine using B20 fuel, particulate PAH emissions increased as engine mileage increased. The average total PAH emission factors were 1097 and 1437 μg bhp h -1 for B20 and diesel, respectively. For B20, the benzo[a]pyrene equivalence emission factors were 0.77, 0.24, 0.20, 7.48, 5.43 and 14.1 μg bhp h -1 for 2-, 3-, 4-, 5-, 6-ringed and total PAHs. Results show that B20 use can reduce both PAH emission and its corresponding carcinogenic potency. (author)

  5. Effects of biodiesel on emissions of regulated air pollutants and polycyclic aromatic hydrocarbons under engine durability testing

    Energy Technology Data Exchange (ETDEWEB)

    Hsi-Hsien Yang; Shu-Mei Chien; Mei-Yu Lo [Chaoyang University of Technology, Wufong (China). Dept. of Environmental Engineering and Management; John Chi-Wei Lan [Yuan Ze University (China). Dept. of Chemical Engineering and Materials Science; Wen-Chang Lu [Industrial Technology Research Institute, Hsinchu (China). New Energy Div.; Yong-Yuan Ku [Automotive Research and Testing Center, Chunhwa (China). Diesel Vehicle Section

    2007-11-15

    An 80,000-km durability test was performed on two engines using diesel and biodiesel (methyl ester of waste cooking oil) as fuel in order to examine emissions resulting from the use of biodiesel. The test biodiesel (B20) was blended with 80% diesel and 20% methyl ester derived from waste cooking oil. Emissions of regulated air pollutants, including CO, HC, NO{sub x}, particulate matter (PM) and polycyclic aromatic hydrocarbons (PAHs) were measured at 20,000-km intervals. The identical-model engines were installed on a standard dynamometer equipped with a dilution tunnel used to measure the pollutants. To simulate real-world driving conditions, emission measurements were made in accordance with the United States Environmental Protection Agency (USEPA) FTP transient cycle guidelines. At 0 km of the durability test, HC, CO and PM emission levels were lower for the B20 engine than those for diesel. After running for 20,000 km and longer, they were higher. However, the deterioration coefficients for these regulated air pollutants were not statistically higher than 1.0, implying that the emission factors do not increase significantly after 80,000 km of driving. Total (gaseous+particulate phase) PAH emission levels for both B20 and diesel decreased as the driving mileage accumulated. However, for the engine using B20 fuel, particulate PAH emissions increased as engine mileage increased. The average total PAH emission factors were 1097 and 1437 {mu}g bhp h{sup -1} for B20 and diesel, respectively. For B20, the benzo[a]pyrene equivalence emission factors were 0.77, 0.24, 0.20, 7.48, 5.43 and 14.1 {mu}g bhp h{sup -1} for 2-, 3-, 4-, 5-, 6-ringed and total PAHs. Results show that B20 use can reduce both PAH emission and its corresponding carcinogenic potency. (author)

  6. Accumulation, allocation, and risk assessment of polycyclic aromatic hydrocarbons (PAHs in soil-Brassica chinensis system.

    Directory of Open Access Journals (Sweden)

    Juan Zhang

    Full Text Available Farmland soil and leafy vegetables accumulate more polycyclic aromatic hydrocarbons (PAHs in suburban sites. In this study, 13 sampling areas were selected from vegetable fields in the outskirts of Xi'an, the largest city in northwestern China. The similarity of PAH composition in soil and vegetation was investigated through principal components analysis and redundancy analysis (RDA, rather than discrimination of PAH congeners from various sources. The toxic equivalent quantity of PAHs in soil ranged from 7 to 202 μg/kg d.w., with an average of 41 μg/kg d.w., which exceeded the agricultural/horticultural soil acceptance criteria for New Zealand. However, the cancer risk level posed by combined direct ingestion, dermal contact, inhalation of soil particles, and inhalation of surface soil vapor met the rigorous international criteria (1 × 10(-6. The concentration of total PAHs was (1052 ± 73 μg/kg d.w. in vegetation (mean ± standard error. The cancer risks posed by ingestion of vegetation ranged from 2×10-5 to 2 × 10(-4 with an average of 1.66 × 10(-4, which was higher than international excess lifetime risk limits for carcinogens (1 × 10(-4. The geochemical indices indicated that the PAHs in soil and vegetables were mainly from vehicle and crude oil combustion. Both the total PAHs in vegetation and bioconcentration factor for total PAHs (the ratio of total PAHs in vegetation to total PAHs in soil increased with increasing pH as well as decreasing sand in soil. The total variation in distribution of PAHs in vegetation explained by those in soil reached 98% in RDA, which was statistically significant based on Monte Carlo permutation. Common pollution source and notable effects of soil contamination on vegetation would result in highly similar distribution of PAHs in soil and vegetation.

  7. Importance of soil NO emissions for the total atmospheric NOxbudget of Saxony, Germany

    DEFF Research Database (Denmark)

    Molina-Herrera, Saúl; Haas, Edwin; Grote, Rüdiger

    2017-01-01

    simulations and measurements significantly increased if data were aggregated to weekly, monthly and seasonal time scales. The model reproduced NO emissions from high and low emitting sites, and responded to fertilization (mineral and organic) events with pulse emissions. After evaluation, we linked...... were by far more important than anthropogenic sources....

  8. Battery condenser system total particulate emission factors and rates for cotton gins: Method 17

    Science.gov (United States)

    This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

  9. Battery condenser system total particulate emission factors and rates for cotton gins

    Science.gov (United States)

    This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

  10. Impact of biomass burning emission on total peroxy nitrates: fire plume identification during the BORTAS campaign

    Directory of Open Access Journals (Sweden)

    E. Aruffo

    2016-11-01

    Full Text Available Total peroxy nitrate ( ∑ PN concentrations have been measured using a thermal dissociation laser-induced fluorescence (TD-LIF instrument during the BORTAS campaign, which focused on the impact of boreal biomass burning (BB emissions on air quality in the Northern Hemisphere. The strong correlation observed between the  ∑ PN concentrations and those of carbon monoxide (CO, a well-known pyrogenic tracer, suggests the possible use of the  ∑ PN concentrations as marker of the BB plumes. Two methods for the identification of BB plumes have been applied: (1  ∑ PN concentrations higher than 6 times the standard deviation above the background and (2  ∑ PN concentrations higher than the 99th percentile of the  ∑ PNs measured during a background flight (B625; then we compared the percentage of BB plume selected using these methods with the percentage evaluated, applying the approaches usually used in literature. Moreover, adding the pressure threshold ( ∼  750 hPa as ancillary parameter to  ∑ PNs, hydrogen cyanide (HCN and CO, the BB plume identification is improved. A recurrent artificial neural network (ANN model was adapted to simulate the concentrations of  ∑ PNs and HCN, including nitrogen oxide (NO, acetonitrile (CH3CN, CO, ozone (O3 and atmospheric pressure as input parameters, to verify the specific role of these input data to better identify BB plumes.

  11. Biomonitoring seasonal variation of urban air polycyclic aromatic hydrocarbons (PAHs) using Ficus benghalensis leaves

    International Nuclear Information System (INIS)

    Prajapati, Santosh Kumar; Tripathi, B.D.

    2008-01-01

    Temporal and seasonal variations of polycyclic aromatic hydrocarbons (PAHs) concentrations in leaves of Ficus benghalensis were investigated in Varanasi city (India). Leaf samples were collected from six sites from urban area of Varanasi and from a control site. PAH extraction was done by sonication in dichloromethane-acetone and quantification by GC-MS. In January total leaf PAHs concentrations at all the urban sites were twice higher as compared to other season's viz. summer and rainy. In contrast, at the control site leaf PAHs concentrations showed lower values than urban sites. The maximum concentrations of total PAHs in winter were due to the medium molecular weight PAHs which increases with respect to both low and high molecular weight PAHs. The temporal variation of medium molecular weight PAHs was similar both at the urban and remote sites. These results support biomonitoring ability of Ficus benghalensis leaves to temporal variations in PAHs contamination. - Biomonitoring PAHs in atmosphere using F. benghalensis leaves for its temporal and seasonal variation is cost effective as well as easier

  12. Phytoremediation of polycyclic aromatic hydrocarbons (PAH) by cv. Crioula: A Brazilian alfalfa cultivar.

    Science.gov (United States)

    Alves, Wilber S; Manoel, Evelin A; Santos, Noemi S; Nunes, Rosane O; Domiciano, Giselli C; Soares, Marcia R

    2018-07-03

    This work aimed to evaluate the phytoremediation capacity of the alfalfa cultivar Crioula in soils contaminated with polycyclic aromatic hydrocarbons (PAHs), primary pollutants with mutagenic and carcinogenic potential. Alfalfa was grown from seed for 40 days on soil amended with anthracene, pyrene, and phenanthrene. Soil and plant tissue was collected for biometric assay, dry mass analysis, and PAH analysis by liquid chromatography. Increased total PAH concentration was associated with decreases in plant biomass, height, and internode length. The Crioula cultivar had a satisfactory phytoremediation effect, reducing total PAH concentration (300 ppm) in the experimental soil by 85% in 20 days, and by more than 95% in 40 days. The PAH showed a tendency to be removed in the temporal order: phenanthrene before pyrene before anthracene, and the removal ratio was influenced by the initial soil concentration of each PAH.

  13. Source identification of Polycyclic Aromatic Hydrocarbons (PAHs in the urban environment of İstanbul

    Directory of Open Access Journals (Sweden)

    Günay Kural

    2018-04-01

    Full Text Available In this study, İstanbul-Tuzla Region atmosphere is selected as the working area because of this region contains shipyards and shipyard-related side product industries. To examine the PAHs as atmospheric inputs, 46 ambient air samples were collected in Tuzla region of Istanbul, Turkey at 2010. The sample collection was carried out as monthly. Additionally, the volume of the air was drawn and meteorological data recorded. The PAH concentrations were classified as hot and cold season samples. Due to the particle-bond character of PAHs and condensation in cold, the high concentrations were encountered in winter months. Monthly average total PAH concentrations fluctuated between 7.4 ng m-3 (in March-0.05 ng m-3 (in August. The concentrations of total PAHs in cold season were almost hundred times higher than those in hot season. The fossil fuel (gasoline and diesel fuel combustion was found to be the main source of PAHs.

  14. Concentration of PAHs in Municipal Wastewater in Selected Sewer Collectors of the Upper Silesian Urban Area, Poland

    Directory of Open Access Journals (Sweden)

    Pistelok Franciszek

    2014-12-01

    (GC-MS. The concentrations of 16 PAHs sum (EPA list ranged between 1.025 and 3.056 μg/L. Phenanthrene dominated in nearly all the analysed samples. The contents of PAHs, which are priority hazardous substances according to the directive, were high in the analysed samples. The obtained results and the analysis of diagnostic ratios for the emissions of PAHs into the air helped to reach the conclusion that traffic emissions were the main source of PAHs in the examined wastewater.

  15. Calculations of total fusion power and spatial distribution of emissivity for a D-T thermal plasma

    International Nuclear Information System (INIS)

    Batistoni, P.; Pillon, M.

    1987-01-01

    The preliminary project of a diagnostic tool to measure the neutron emissivity profile for NET (Next European Torus) with an array of collimators is presented. With the help of a neutron transport code the maximum possible number of collimators, compatible with the crosstalk noise and the space available in the NET 2.2.B is determined within these constraints. An array of 17 collimators can be used, and some experimental results are simulated using a Monte Carlo code. These results are analyzed and an inversion procedure is used to obtain the emissivity profile and evaluate the total fusion power. The results show that the total fusion power can be measured within 10% for different emission profiles

  16. Influence of the sunflower rhizosphere on the biodegradation of PAHs in soil

    OpenAIRE

    Tejeda Agredano, M. C.; Gallego, Sara; Vila, Joaquim; Ortega Calvo, J. J.; Cantos, Manuel

    2013-01-01

    Reduced bioavailability to soil microorganisms is probably the most limiting factor in the bioremediation of polycyclic aromatic hydrocarbons PAH-polluted soils. We used sunflowers planted in pots containing soil to determine the influence of the rhizosphere on the ability of soil microbiota to reduce PAH levels. The concentration of total PAHs decreased by 93% in 90 days when the contaminated soil was cultivated with sunflowers, representing an improvement of 16% compared to contaminated soi...

  17. Quantifying the relative contribution of natural gas fugitive emissions to total methane emissions in Colorado and Utah using mobile stable isotope (13CH4) analysis

    Science.gov (United States)

    Rella, Chris; Jacobson, Gloria; Crosson, Eric; Karion, Anna; Petron, Gabrielle; Sweeney, Colm

    2013-04-01

    Fugitive emissions of methane into the atmosphere are a major concern facing the natural gas production industry. Because methane is more energy-rich than coal per kg of CO2 emitted into the atmosphere, it represents an attractive alternative to coal for electricity generation. However, given that the global warming potential of methane is many times greater than that of carbon dioxide (Solomon et al. 2007), the importance of quantifying the fugitive emissions of methane throughout the natural gas production and distribution process becomes clear (Howarth et al. 2011). A key step in the process of assessing the emissions arising from natural gas production activities is partitioning the observed methane emissions between natural gas fugitive emissions and other sources of methane, such as from landfills or agricultural activities. One effective method for assessing the contribution of these different sources is stable isotope analysis. In particular, the 13CH4 signature of natural gas (-35 to -40 permil) is significantly different that the signature of other significant sources of methane, such as landfills or ruminants (-45 to -70 permil). In this paper we present measurements of mobile field 13CH4 using a spectroscopic stable isotope analyzer based on cavity ringdown spectroscopy, in two intense natural gas producing regions of the United States: the Denver-Julesburg basin in Colorado, and the Uintah basin in Utah. Mobile isotope measurements in the nocturnal boundary layer have been made, over a total path of 100s of km throughout the regions, allowing spatially resolved measurements of the regional isotope signature. Secondly, this analyzer was used to quantify the isotopic signature of those individual sources (natural gas fugitive emissions, concentrated animal feeding operations, and landfills) that constitute the majority of methane emissions in these regions, by making measurements of the isotope ratio directly in the downwind plume from each source. These

  18. Risk assessment of metals and PAHs for receptor organisms in differently polluted areas in Slovenia.

    Science.gov (United States)

    Al Sayegh Petkovšek, Samar; Kopušar, Nataša; Tome, Davorin; Kryštufek, Boris

    2015-11-01

    Samples from receptor organisms (small mammals, passerine birds) and their food sources (herbaceous plants, leaves and fruits of wood plants, earthworms) were collected during 2011-2014 from the vicinity of a former lead smelter, from the vicinity of the largest Slovenian thermal power plant, from along a state road and also from a reference area. The samples were then analysed to determine the degree of contamination with the metals (Pb, Cd, Zn, Hg, Cu, Mo) and with polycyclic aromatic hydrocarbons (PAHs). This study provides the first data on metal and PAH exposure to small mammals and passerine birds in southeast Europe, focussing on the transfer of metals and PAHs through the food chain and on risk assessment for differently polluted areas in Slovenia. The results indicate that: (i) earthworms and herbaceous plants (especially roots) can be a source of metal exposure for organisms higher in the food chain; (ii) a risk from Pb and Cd (HQ > 1) in the vicinity of the former lead smelter exists for Myodes glareolus feeding in part on roots and for Apodemus flavicollis and Parus major feeding in part on earthworms; and (iii) mean Pb and Cd concentrations in the liver of small mammal species inhabiting the vicinity of the lead smelter reach effect concentrations in a significant proportion of the specimens (Pb: 40%, Cd: 67%); (iv) the results for P. major confirm that the study area is exposed to Pb, Cd, Hg; (v) metals contribute the major part of the total risk for receptor organisms from vicinity of lead smelter. On the contrary, the risk of PAHs for small mammals trapped close to the state road is insignificant. We can summarize, that the hazards experienced by the local ecosystem due to metal exposure may persist for decades in the vicinity of large emission sources (especially smelters). Copyright © 2015 Elsevier B.V. All rights reserved.

  19. PAHs in Translucent Interstellar Clouds

    Science.gov (United States)

    Salama, Farid; Galazutdinov, G.; Krelowski, J.; Biennier, L.; Beletsky, Y.; Song, I.

    2011-05-01

    We discuss the proposal of relating the origin of some of the diffuse interstellar bands (DIBs) to neutral polycyclic aromatic hydrocarbons (PAHs) present in translucent interstellar clouds. The spectra of several cold, isolated gas-phase PAHs have been measured in the laboratory under experimental conditions that mimic the interstellar conditions and are compared with an extensive set of astronomical spectra of reddened, early type stars. This comparison provides - for the first time - accurate upper limits for the abundances of specific PAH molecules along specific lines-of-sight. Something that is not attainable from IR observations alone. The comparison of these unique laboratory data with high resolution, high S/N ratio astronomical observations leads to two major findings: (1) a finding specific to the individual molecules that were probed in this study and, which leads to the clear and unambiguous conclusion that the abundance of these specific neutral PAHs must be very low in the individual translucent interstellar clouds that were probed in this survey (PAH features remain below the level of detection) and, (2) a general finding that neutral PAHs exhibit intrinsic band profiles that are similar to the profile of the narrow DIBs indicating that the carriers of the narrow DIBs must have close molecular structure and characteristics. This study is the first quantitative survey of neutral PAHs in the optical range and it opens the way for unambiguous quantitative searches of PAHs in a variety of interstellar and circumstellar environments. // Reference: F. Salama et al. (2011) ApJ. 728 (1), 154 // Acknowledgements: F.S. acknowledges the support of the NASA's Space Mission Directorate APRA Program. J.K. acknowledges the financial support of the Polish State (grant N203 012 32/1550). The authors are deeply grateful to the ESO archive as well as to the ESO staff members for their active support.

  20. PAH partitioning in a toxicity exposure chamber

    International Nuclear Information System (INIS)

    Sterling, M.C. Jr.; Autenrieth, R.L.; Bonner, J.S.; Page, C.A.; Fuller, C.B.; Ernest, A.N.S.

    2003-01-01

    The hypothesis that observed petroleum aromatic hydrocarbon (PAH) concentrations in an aqueous system are equal to the sum of the organic phase and the soluble phase molar concentrations was examined. Raoult's law was used to estimate the soluble phase molar concentrations. The organic phase concentrations were proportional to the PAH mole fraction in the oil. The experiment involved initially loading a batch laboratory mixing vessel with a scalable mixing energy at various oil layer thicknesses corresponding to oil surface loadings. The vessel was then agitated at a constant mean shear rate. Periodical total petroleum hydrocarbon (TPH) samples were taken in order to estimate the entrainment rate as a function of initial oil layer thickness. In-situ measurements of TPH concentrations were performed with the use of a laser scattering instrument while ex-situ measurements were effected using gravimetric analysis. Additional samples were analyzed for PAH concentration at a steady state TPH concentration using gas chromatograph/mass spectrometer (GC/MS) analysis. The results obtained were in agreement with a first order kinetic model (TPH concentrations increased over time). It was noted that in general, the first order rate constant and steady state concentration increased with increased oil loading and increased mean shear rates. There was good correlation between the measurements and the concentrations predicted using the hypothesized model. 8 refs., 3 tabs., 2 figs

  1. The North Cape oil spill assessment: PAHs in oil

    International Nuclear Information System (INIS)

    Brown, J.; Boehm, P. D.; Hardestine, J. H.; Douglas, G. S.

    1997-01-01

    The North Cape oil spill in January 1996 resulted in the release of an estimated 827,000 gallons of No. 2 home heating oil into the nearshore turbulent waters of coastal Rhode Island. The oil was mixed into the water column and was transported on the surface as well as below the surface. Some of the spilled oil entered the coastal ponds behind the beaches. Sampling and chemical analysis for detailed suites of petroleum saturated and polycyclic aromatic hydrocarbons (PAHs) was undertaken as part of the assessment of the fate of the oil spill and of the exposure to the marine environment. The ponds were found to contain significant quantities of background petroleum hydrocarbons, including petrogenic PAHs and combustion PAHs. Initial assessment pointed (incorrectly as it turned out) to widespread contamination due only to the North Cape spill. Application of advanced chemical fingerprinting approaches, and geochemical biomarker data illustrated that many of the PAHs consisted of combustion-related 4- and 5-ringed PAHs, attributable to diesel fuel used routinely by boats in the area. The analysis demonstrated that the use of non-specific total PAH data and insufficient fingerprinting and allocation of petrogenic residues has the potential to overestimate contamination and hence injury to the environment in similar oil spill situations

  2. Study of remobilization polycyclic aromatic hydrocarbons (PAHs) in contaminated matrices

    International Nuclear Information System (INIS)

    Belkessam, L.; Vessigaud, S.; Laboudigue, A.; Vessigaud, S.; Perrin-Ganier, C.; Schiavon, M.; Denys, S.

    2005-01-01

    Polycyclic aromatic hydrocarbons (PAHs) originate from many pyrolysis processes. They are widespread environmental pollutants because some of them present toxic and genotoxic properties. In coal pyrolysis sites such as former manufactured gas plants and coke production plants, coal tar is a major source of PAHs. The management of such sites requires better understanding of the mechanisms that control release of PAHs to the biosphere. Determining total PAH concentrations is not sufficient since it does not inform about the pollutants availability to environmental processes. The fate and transport of PAHs in soil are governed by sorption and microbial processes which are well documented. Globally, enhancing retention of the compounds by a solid matrix reduces the risk of pollutant dispersion, but decreases their accessibility to microbial microflora. Conversely, the remobilization of organics from contaminated solid matrices represents a potential hazard since these pollutants can reach groundwater resources. However the available data are often obtained from laboratory experiments in which many field parameters can not be taken into account (long term, temperature, co-pollution, ageing phenomenon, heterogenous distribution of pollution). The present work focuses on the influence assessment and understanding of some of these parameters on PAHs remobilization from heavily polluted matrices in near-field conditions (industrial contaminated matrices, high contact time, ..). Results concerning effects of temperature and physical state of pollution (dispersed among the soil or condensed in small clusters or in coal tar) are presented. (authors)

  3. Generation of polycyclic aromatic hydrocarbons (PAH during woodworking operations

    Directory of Open Access Journals (Sweden)

    Evin Danisman Bruschweiler

    2012-10-01

    Full Text Available Occupational exposures to wood dust have been associated with an elevated risk of sinonasal cancer (SNC. Wood dust is recognized as a human carcinogen but the specific cancer causative agent remains unknown. One possible explanation is a co-exposure to; wood dust and polycyclic aromatic hydrocarbons (PAHs. PAHs could be generated during incomplete combustion of wood due to heat created by use of power tools.To determine if PAHs are generated from wood during common woodworking operations, PAHs concentrations in wood dust samples collected in an experimental chamber operated under controlled conditions were analyzed. In addition, personal air samples from workers exposed to wood dust (n=30 were collected.Wood dust was generated using tree different power tools: vibrating sander, belt sander, and saw; and six wood materials: fir, Medium Density Fiberboard (MDF, beech, mahogany, oak and wood melamine. Monitoring of wood workers was carried out by means of personnel sampler device during wood working operations. We measured 21 PAHs concentrations in wood dust samples by capillary gas chromatographic-ion trap mass spectrometric analysis (GC-MS.Total PAH concentrations in wood dust varied greatly (0.24 – 7.95 ppm with the lowest being in MDF dust and the highest in wood melamine dust. Personal exposures to PAHs observed were between 37.5-119.8 ng m-3 among workers during wood working operations.Our results suggest that PAH exposures during woodworking operation are present and hence could play a role in the mechanism of cancer induction related to wood dust exposure.

  4. [The mutation analysis of PAH gene and prenatal diagnosis in classical phenylketonuria family].

    Science.gov (United States)

    Yan, Yousheng; Hao, Shengju; Yao, Fengxia; Sun, Qingmei; Zheng, Lei; Zhang, Qinghua; Zhang, Chuan; Yang, Tao; Huang, Shangzhi

    2014-12-01

    To characterize the mutation spectrum of phenylalanine hydroxylase (PAH) gene and perform prenatal diagnosis for families with classical phenylketonuria. By stratified sequencing, mutations were detected in the exons and flaking introns of PAH gene of 44 families with classical phenylketonuria. 47 fetuses were diagnosed by combined sequencing with linkage analysis of three common short tandem repeats (STR) (PAH-STR, PAH-26 and PAH-32) in the PAH gene. Thirty-one types of mutations were identified. A total of 84 mutations were identified in 88 alleles (95.45%), in which the most common mutation have been R243Q (21.59%), EX6-96A>G (6.82%), IVS4-1G>A (5.86%) and IVS7+2T>A (5.86%). Most mutations were found in exons 3, 5, 6, 7, 11 and 12. The polymorphism information content (PIC) of these three STR markers was 0.71 (PAH-STR), 0.48 (PAH-26) and 0.40 (PAH-32), respectively. Prenatal diagnosis was performed successfully with the combined method in 47 fetuses of 44 classical phenylketonuria families. Among them, 11 (23.4%) were diagnosed as affected, 24 (51.1%) as carriers, and 12 (25.5%) as unaffected. Prenatal diagnosis can be achieved efficiently and accurately by stratified sequencing of PAH gene and linkage analysis of STR for classical phenylketonuria families.

  5. The economic burden of pulmonary arterial hypertension (PAH) in the US on payers and patients.

    Science.gov (United States)

    Sikirica, Mirko; Iorga, Serban R; Bancroft, Tim; Potash, Jesse

    2014-12-24

    Pulmonary arterial hypertension (PAH) is a rare condition that can ultimately lead to right heart failure and death. In this study we estimated the health care costs and resource utilization associated with PAH in a large US managed care health plan. Subjects with claims-based evidence of PAH from 1/1/2004 to 6/30/2010 (identification period) were selected. To be included in the final PAH study sample, subjects were required to have ≥2 claims with a primary PH diagnosis; ≥2 claims with a PAH related-diagnosis (connective tissue diseases, congenital heart diseases, portal hypertension); and ≥1 claim with evidence of a PAH-indicated medication. The earliest date of a claim with evidence of PAH-indicated medication during the identification period was set as the index date. Health care costs and resource utilization were compared between an annualized baseline period and a 12 month follow-up period. 504 PAH subjects were selected for the final study cohort. Estimated average total health care costs were approximately 16% lower in the follow-up period compared to the baseline period (follow-up costs = $98,243 [SD = 110,615] vs. baseline costs = $116,681 [SD = 368,094], p PAH had substantively high health care costs. Medical costs appeared to decrease following PAH medication use, but with a concomitant increase in pharmacy costs.

  6. Senyawa polisiklik aromatik hidrokarbon (PAH dalam air laut di Teluk Jakarta

    Directory of Open Access Journals (Sweden)

    Edward .

    2014-01-01

    Full Text Available Research on polycyclic aromatic hydrocarbons (pahs compound at Jakarta Bay seawater were carried out on July 2011. The objectives of this research were to measure the concentration of total polycyclic aromatic hydrocarbons (PAH compound, concentration of individual PAH compound, and to identify sources of PAH compound in seawater. PAH compound concentration was measured by Gas Chromatography (Gas Chromatography-Flame Ionization Detector and sources of polycyclic aromatic hydrocarbons compound were identified by diagnostic ratio analysis. The results show that the concentration of PAH compound in the middle of Jakarta Bay was higher compared to the west and the east. In the west and middle of Jakarta Bay, it is found that 11 PAH types, and 10 types in the east. Individual PAH compound dominated by high moleculer weight of PAH Benzo(aAnthracene, Chrysene, Benzo(bFluoranthene, Benzo(aPyrene, dan Indeno(123-cd Pyrene. The results of PAH compound ratio individual analysis showed that polycyclic aromatic hydrocarbons compound at Jakarta Bay seawater came from oil spill and incomplete combustion mixture of organic material such as wood, grass, fuel oil, and fuel industry combustion activity.

  7. Characterization of polycyclic aromatic hydrocarbon emissions in the particulate and gas phase from smoldering mosquito coils containing various atomic hydrogen/carbon ratios

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Tzu-Ting, E-mail: d89844001@ntu.edu.tw [Department of Environmental Engineering and Health, Yuanpei University, No. 306, Yuanpei St., Hsin Chu 30015, Taiwan (China); Lin, Shaw-Tao [Department of Applied Chemistry, Providence University, No. 200 Chung-Chi Rd., Salu Dist., Taichung City 43301, Taiwan (China); Lin, Tser-Sheng [Department of Safety, Health, and Environmental Engineering, National United University, 2 Lien Da, Maioli 360, Taiwan (China); Chung, Hua-Yi [Department of Environmental Engineering and Health, Yuanpei University, No. 306, Yuanpei St., Hsin Chu 30015, Taiwan (China)

    2015-02-15

    The polycyclic aromatic hydrocarbon emissions in particulate and gas phases generated from smoldering mosquito coils containing various atomic H/C ratios were examined. Five types of mosquito coils were burned in a test chamber with a total airflow rate of 8.0 L/min at a constant relative humidity and temperature. The concentrations of individual PAHs were determined using the GC/MS technique. Among the used mosquito coils, the atomic H/C ratio ranged from 1.23 to 1.57, yielding total mass, gaseous, and particulate PAH emission factors of 28.17–78.72 mg/g, 26,139.80–35,932.98 and 5735.22–13,431.51 ng/g, respectively. The various partitions of PAHs in the gaseous and particulate phases were in the ranges, 70.26–83.70% and 16.30–29.74% for the utilized mosquito coils. The carcinogenic potency of PAH emissions in the particulate phase (203.82–797.76 ng/g) was approximately 6.92–25.08 times higher than that of the gaseous phase (26.27–36.07 ng/g). Based on the analyses of PAH emissions, mosquito coils containing the lowest H/C ratio, a low oxygen level, and additional additives (i.e., CaCO{sub 3}) are recommended for minimizing the production of total PAH emission factors and carcinogenic potency. - Highlights: • PAHs emissions are influenced by mosquito coils containing various atomic H/C ratios. • The PAHs generated by burning mosquito coils mainly occur in the gaseous phase. • Total TEQ emission factors of PAHs mainly consisted of the particulate phase (> 87%). • The BaP and BaA accounted for 71.13–77.28% of the total TEQ emission factors. • Special PAH ratios were regarded as characteristic ratios for burning mosquito coil.

  8. A novel field measurement method for determining fine particle and gas emissions from residential wood combustion

    Science.gov (United States)

    Tissari, Jarkko; Hytönen, Kati; Lyyränen, Jussi; Jokiniemi, Jorma

    Emission data from residential wood combustion are usually obtained on test stands in the laboratory but these measurements do not correspond to the operational conditions in the field because of the technological boundary conditions (e.g. testing protocol, environmental and draught conditions). The field measurements take into account the habitual practice of the operators and provide the more reliable results needed for emission inventories. In this study, a workable and compact method for measuring emissions from residential wood combustion in winter conditions was developed. The emissions for fine particle, gaseous and PAH compounds as well as particle composition in real operational conditions were measured from seven different appliances. The measurement technique worked well and was evidently suitable for winter conditions. It was easy and fast to use, and no construction scaffold was needed. The dilution of the sample with the combination of a porous tube diluter and an ejector diluter was well suited to field measurement. The results indicate that the emissions of total volatile organic carbon (TVOC) (17 g kg -1 (of dry wood burned)), carbon monoxide (CO) (120 g kg -1) and fine particle mass (PM 1) (2.7 g kg -1) from the sauna stove were higher than in the other measured appliances. In the masonry heaters, baking oven and stove, the emissions were 2.9-9 g kg -1 TVOC, 28-68 g kg -1 CO and 0.6-1.6 g kg -1 PM 1. The emission of 12 PAHs (PAH 12) from the sauna stove was 164 mg kg -1 and consisted mainly of PAHs with four benzene rings in their structure. PAH 12 emission from other appliances was, on average, 21 mg kg -1 and was dominated by 2-ring PAHs. These results indicate that despite the non-optimal operational practices in the field, the emissions did not differ markedly from the laboratory measurements.

  9. Levels and patterns of polycyclic aromatic hydrocarbons (PAHs) in soils after forest fires in South Korea.

    Science.gov (United States)

    Kim, Eun Jung; Choi, Sung-Deuk; Chang, Yoon-Seok

    2011-11-01

    To investigate the influence of biomass burning on the levels of polycyclic aromatic hydrocarbons (PAHs) in soils, temporal trends and profiles of 16 US Environmental Protection Agency priority PAHs were studied in soil and ash samples collected 1, 5, and 9 months after forest fires in South Korea. The levels of PAHs in the burnt soils 1 month after the forest fires (mean, 1,200 ng/g dry weight) were comparable with those of contaminated urban soils. However, 5 and 9 months after the forest fires, these levels decreased considerably to those of general forest soils (206 and 302 ng/g, respectively). The burnt soils and ash were characterized by higher levels of light PAHs with two to four rings, reflecting direct emissions from biomass burning. Five and 9 months after the forest fires, the presence of naphthalene decreased considerably, which indicates that light PAHs were rapidly volatilized or degraded from the burnt soils. The temporal trend and pattern of PAHs clearly suggests that soils in the forest-fire region can be contaminated by PAHs directly emitted from biomass burning. However, the fire-affected soils can return to the pre-fire conditions over time through the washout and wind dissipation of the ash with high content of PAHs as well as vaporization or degradation of light PAHs.

  10. Assisted Interpretation of Laser-Induced Fluorescence Spectra of Egg-Based Binding Media Using Total Emission Fluorescence Spectroscopy

    International Nuclear Information System (INIS)

    Anglos, D.; Nevin, A.

    2006-01-01

    Laser-induced fluorescence (LIF) spectroscopy can provide nondestructive, qualitative analysis of protein-based binding media found in artworks. Fluorescence emissions from proteins in egg yolk and egg white are due to auto fluorescent aromatic amino acids as well as other native and age-related fluorophores, but the potential of fluorescence spectroscopy for the differentiation between binding media is dependent on the choice of a suitable excitation wavelength and limited by problems in interpretation. However, a better understanding of emission spectra associated with LIF can be achieved following comparisons with total emission fluorescence spectra where a series of consecutive emission spectra are recorded over a specific range. Results using nanosecond UV laser sources for LIF of egg-based binding media are presented which are rationalised following comparisons with total emission spectra. Specifically, fluorescence is assigned to tryptophan and oxidation products of amino acids; in the case of egg yolk, fatty-acid polymerisation and age-related degradation products account for the formation of fluorophores.

  11. Response of microbial activities and diversity to PAHs contamination at coal tar contaminated land

    Science.gov (United States)

    Zhao, Xiaohui; Sun, Yujiao; Ding, Aizhong; Zhang, Dan; Zhang, Dayi

    2015-04-01

    Coal tar is one of the most hazardous and concerned organic pollutants and the main hazards are polycyclic aromatic hydrocarbons (PAHs). The indigenous microorganisms in soils are capable to degrade PAHs, with essential roles in biochemical process for PAHs natural attenuation. This study investigated 48 soil samples (from 8 depths of 6 boreholes) in Beijing coking and chemistry plant (China) and revealed the correlation between PAHs contamination, soil enzyme activities and microbial community structure, by 16S rRNA denaturing gradient gel electrophoresis (DGGE). At the site, the key contaminants were identified as naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene and anthracene, and the total PAHs concentration ranged from 0.1 to 923.9 mg/kg dry soil. The total PAHs contamination level was positively correlated (pcatalase activities (0.554-6.230 mL 0.02 M KMnO4/g•h) and dehydrogenase activities (1.9-30.4 TF μg/g•h soil), showing the significant response of microbial population and degrading functions to the organic contamination in soils. The PAHs contamination stimulated the PAHs degrading microbes and promoted their biochemical roles in situ. The positive relationship between bacteria count and dehydrogenase activities (p<0.05) suggested the dominancy of PAHs degrading bacteria in the microbial community. More interestingly, the microbial community deterioration was uncovered via the decline of microbial biodiversity (richness from 16S rRNA DGGE) against total PAHs concentration (p<0.05). Our research described the spatial profiles of PAHs contamination and soil microbial functions at the PAHs heavily contaminated sites, offering deeper understanding on the roles of indigenous microbial community in natural attenuation process.

  12. Estimation of Total Yearly CO2 Emissions by Wildfires in Mexico during the Period 1999–2010

    Directory of Open Access Journals (Sweden)

    Flor Bautista Vicente

    2014-01-01

    Full Text Available The phenomenon of wildfires became a global environmental problem which demands estimations of their CO2 emissions. Wildfires have deteriorated the air quality increasingly. Using available information on documented wildfires and a data set of satellite detected hot spots, total yearly emissions of CO2 in Mexico were estimated for the period 1999–2010. A map of the main vegetation groups was used to calculate total areas for every vegetation type. The yearly number of hot spots per vegetation type was calculated. Estimates of emitted CO2 in a wildfire were then accomplished by considering parameters such as: forest fuel load, vegetation type, burning efficiency, and mean burned area. The number of wildfires and total affected areas showed an annual variability. The yearly mean of affected area by a single wildfire varied between 0.2 and 0.3 km2. The total affected area during the period 1999 to 2010 was 86800 km2 which corresponds to 4.3% of the Mexican territory. Total CO2 emissions were approximately 112 Tg. The most affected vegetation types were forest and rainforest.

  13. PAHs contamination in urban soils from Lisbon: spatial variability and potential risks

    Science.gov (United States)

    Cachada, Anabela; Pereira, Ruth; Ferreira da Silva, Eduardo; Duarte, Armando

    2015-04-01

    Polycyclic Aromatic hydrocarbons (PAHs) can become major contaminants in urban and industrial areas, due to the existence of a plethora of diffuse and point sources. Particularly diffuse pollution, which is normally characterized by continuous and long-term emission of contaminants below risk levels, can be a major problem in urban areas. Since PAHs are persistent and tend to accumulate in soils, levels are often above the recommended guidelines indicating that ecological functions of soils may be affected. Moreover, due to the lipophilic nature, hydrophobicity and low chemical and biological degradation rates of PAHs, which leads to their bioconcentration and bioamplification, they may reach toxicological relevant concentrations in organisms. The importance and interest of studying this group of contaminants is magnified due to their carcinogenic, mutagenic and endocrine disrupting effects. In this study, a risk assessment framework has been followed in order to evaluate the potential hazards posed by the presence of PAHs in Lisbon urban soils. Hence, the first step consisted in screening the total concentrations of PAHs followed by the calculation of risks based on existing models. Considering these models several samples were identified as representing a potential risk when comparing with the guidelines for soil protection. Moreover, it was found that for 38% of samples more than 50% of species can be potentially affected by the mixture of PAHs. The use of geostatistical methods allowed to visualize the predicted distribution of PAHs in Lisbon area and identify the areas where possible risk to the environment are likely occurring However, it is known that total concentration may not allow a direct prediction of environmental risk, since in general only a fraction of total concentration is available for partitioning between soil and solution and thus to be uptake or transformed by organisms (bioacessible or bioavailable) or to be leached to groundwater. The

  14. Remarkably constant PAH concentrations in Swiss soils over the last 30 years.

    Science.gov (United States)

    Gubler, Andreas; Wächter, Daniel; Blum, Franziska; Bucheli, Thomas D

    2015-10-01

    Although polycyclic aromatic hydrocarbons (PAH) are of concern due to their carcinogenic, mutagenic, and teratogenic properties and their ubiquitous occurrence in environmental compartments, only few studies assessed the temporal evolutions of PAH contents of soils over extended time periods. The Swiss Soil Monitoring Network NABO runs long-term monitoring sites resampled every five years since the 1980s. In the present study, soil (0-20 cm) samples collected from 1985 through 2013 at 25 selected monitoring sites were analysed for the 16 priority PAH according to the U.S. EPA and five PAH marker substances. We observed divergent trends for light PAH, such as naphthalene and phenanthrene, compared with heavy PAH, such as benzo[a]pyrene and benzo[ghi]perylene. Whereas the former showed decreasing concentrations since the late 1980s, no significant trends were found for the latter. Furthermore, the analyses showed that naphthalene contents decreased most strongly at rural sites featuring low population densities, while phenanthrene contents generally decreased most strongly at semi-rural sites. The deviating evolutions of light and heavy PAH were mainly attributed to their differing physico-chemical properties. Temporal evolutions in soils contradict emission inventory data suggesting PAH emissions to decline since the 1980s.

  15. Distribution of PAHs and the PAH-degrading bacteria in the deep-sea sediments of the high-latitude Arctic Ocean

    Science.gov (United States)

    Dong, C.; Bai, X.; Sheng, H.; Jiao, L.; Zhou, H.; Shao, Z.

    2015-04-01

    Polycyclic aromatic hydrocarbons (PAHs) are common organic pollutants that can be transferred long distances and tend to accumulate in marine sediments. However, less is known regarding the distribution of PAHs and their natural bioattenuation in the open sea, especially the Arctic Ocean. In this report, sediment samples were collected at four sites from the Chukchi Plateau to the Makarov Basin in the summer of 2010. PAH compositions and total concentrations were examined with GC-MS. The concentrations of 16 EPA-priority PAHs varied from 2.0 to 41.6 ng g-1 dry weight and decreased with sediment depth and movement from the southern to the northern sites. Among the targeted PAHs, phenanthrene was relatively abundant in all sediments. The 16S rRNA gene of the total environmental DNA was analyzed with Illumina high-throughput sequencing (IHTS) to determine the diversity of bacteria involved in PAH degradation in situ. The potential degraders including Cycloclasticus, Pseudomonas, Halomonas, Pseudoalteromonas, Marinomonas, Bacillus, Dietzia, Colwellia, Acinetobacter, Alcanivorax, Salinisphaera and Shewanella, with Dietzia as the most abundant, occurred in all sediment samples. Meanwhile, enrichment with PAHs was initiated onboard and transferred to the laboratory for further enrichment and to obtain the degrading consortia. Most of the abovementioned bacteria in addition to Hahella, Oleispira, Oceanobacter and Hyphomonas occurred alternately as predominant members in the enrichment cultures from different sediments based on IHTS and PCR-DGGE analysis. To reconfirm their role in PAH degradation, 40 different bacteria were isolated and characterized, among which Cycloclasticus Pseudomonas showed the best degradation capability under low temperatures. Taken together, PAHs and PAH-degrading bacteria were widespread in the deep-sea sediments of the Arctic Ocean. We propose that bacteria of Cycloclasticus, Pseudomonas, Pseudoalteromonas, Halomonas, Marinomonas and Dietzia may

  16. Quantifying the relative contribution of natural gas fugitive emissions to total methane emissions in Colorado, Utah, and Texas using mobile δ13CH4 analysis

    Science.gov (United States)

    Rella, C.; Crosson, E.; Petron, G.; Sweeney, C.; Karion, A.

    2013-12-01

    Fugitive emissions of methane into the atmosphere are a major concern facing the natural gas production industry. Because methane is more energy-rich than coal per kg of CO2 emitted into the atmosphere, it represents an attractive alternative to coal for electricity generation, provided that the fugitive emissions of methane are kept under control. A key step in assessing these emissions in a given region is partitioning the observed methane emissions between natural gas fugitive emissions and other sources of methane, such as from landfills or agricultural activities. One effective method for assessing the contribution of these different sources is stable isotope analysis, using the δ13CH4 signature to distinguish between natural gas and landfills or ruminants. We present measurements of mobile field δ13CH4 using a spectroscopic stable isotope analyzer based on cavity ringdown spectroscopy, in three intense natural gas producing regions of the United States: the Denver-Julesburg basin in Colorado, the Uintah basin in Utah, and the Barnett Shale in Texas. Mobile isotope measurements of individual sources and in the nocturnal boundary layer have been combined to establish the fraction of the observed methane emissions that can be attributed to natural gas activities. The fraction of total methane emissions in the Denver-Julesburg basin attributed to natural gas emissions is 78 +/- 13%. In the Uinta basin, which has no other significant sources of methane, the fraction is 96% +/- 15%. In addition, results from the Barnett shale are presented, which includes a major urban center (Dallas / Ft. Worth). Methane emissions in this region are spatially highly heterogeneous. Spatially-resolved isotope and concentration measurements are interpreted using a simple emissions model to arrive at an overall isotope ratio for the region. (left panel) Distribution of oil and gas well pads (yellow) and landfills (blue) in the Dallas / Ft. Worth area. Mobile nocturnal measurements

  17. Quantifying the relative contribution of natural gas fugitive emissions to total methane emissions in Weld County Colorado using δ13CH4 analysis

    Science.gov (United States)

    Rella, C.; Jacobson, G. A.; Crosson, E.; Sweeney, C.; Karion, A.; Petron, G.

    2012-12-01

    Fugitive emissions of methane into the atmosphere are a major concern facing the natural gas production industry. Given that the global warming potential of methane is many times greater than that of carbon dioxide (Forster et al. 2007), the importance of quantifying methane emissions becomes clear. Companion presentations at this meeting describe efforts to quantify the overall methane emissions in two separate gas producing areas in Colorado and Utah during intensive field campaigns undertaken in 2012. A key step in the process of assessing the emissions arising from natural gas production activities is partitioning the observed methane emissions between natural gas fugitive emissions and other sources of methane, such as from landfills or agricultural activities. One method for assessing the contribution of these different sources is stable isotope analysis. In particular, the δ13CH4 signature of natural gas (-37 permil) is significantly different that the signature of other significant sources of methane, such as landfills or ruminants (-50 to -70 permil). In this paper we present measurements of δ13CH4 in Colorado in Weld County, a region of intense natural gas production, using a mobile δ13CH4¬ analyzer capable of high-precision measurements of the stable isotope ratio of methane at ambient levels. This analyzer was used to make stable isotope measurements at a fixed location near the center of the gas producing region, from which an overall isotope ratio for the regional emissions is determined. In addition, mobile measurements in the nocturnal boundary layer have been made, over a total distance of 150 km throughout Weld County, allowing spatially resolved measurements of this isotope signature. Finally, this analyzer was used to quantify the isotopic signature of those individual sources (natural gas fugitive emissions, concentrated animal feeding operations, and landfills) that constitute the majority of methane emissions in this region, by making

  18. 1-hydroxypyrene as a biomarker of PAH exposure in the marine invertebrates N. diversicolor

    DEFF Research Database (Denmark)

    Tairova, Zhanna; Giessing, Anders; Hansen, Rikke

    Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous, persistent and toxic contaminants in the marine environment. Uptake of PAHs by marine deposit-feeding invertebrates can be determined by screening for PAH-derived metabolites. Methods for detection and quantification of PAH metabolites may...... invertebrates is on the other hand practically non-existing. The present study investigated formation of pyrene metabolites in the marine polychaete Nereis diversicolor, with special attention given to the detection of 1-hydroxypyrene. 1-hydroxypyrene was identified in tissues of Nereis diversicolor exposed...... this context the usefulness of SFS for identification and quantification was explored. Considering the complex composition of environmental PAH pollution, before the 1-hydoxypyrene in tissues of exposed marine invertebrates can be regarded as a suitable biomarker for assessing total PAH exposure...

  19. Assessment of polycyclic aromatic hydrocarbons (PAHs) in mussels (Mytilus galloprovincialis) of Prince Islands, Marmara Sea.

    Science.gov (United States)

    Balcıoğlu, Esra Billur

    2016-08-15

    In this study, PAH analyses have been conducted on indigenous mussels. Mussel samples (Mytilus galloprovincialis) have been collected from seven stations of Prince Islands during September 2015. Concentrations of total determined PAHs (sum of 16 compounds) ranged between 664 and 9083ngg(-1). The origin of PAHs has been found to be pyrolytic according to the PHE/ANT and FA/PYR ratios in Büyükada. For other islands, PAH origins have been observed as pyrolytic and petrogenic together according to the PHE/ANT, FA/PYR and BaA/CHR ratios. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Developmental toxicity of PAH mixtures in fish early life stages. Part II: adverse effects in Japanese medaka.

    Science.gov (United States)

    Le Bihanic, Florane; Clérandeau, Christelle; Le Menach, Karyn; Morin, Bénédicte; Budzinski, Hélène; Cousin, Xavier; Cachot, Jérôme

    2014-12-01

    In aquatic environments, polycyclic aromatic hydrocarbons (PAHs) mostly occur as complex mixtures, for which risk assessment remains problematic. To better understand the effects of PAH mixture toxicity on fish early life stages, this study compared the developmental toxicity of three PAH complex mixtures. These mixtures were extracted from a PAH-contaminated sediment (Seine estuary, France) and two oils (Arabian Light and Erika). For each fraction, artificial sediment was spiked at three different environmental concentrations roughly equivalent to 0.5, 4, and 10 μg total PAH g(-1) dw. Japanese medaka embryos were incubated on these PAH-spiked sediments throughout their development, right up until hatching. Several endpoints were recorded at different developmental stages, including acute endpoints, morphological abnormalities, larvae locomotion, and genotoxicity (comet and micronucleus assays). The three PAH fractions delayed hatching, induced developmental abnormalities, disrupted larvae swimming activity, and damaged DNA at environmental concentrations. Differences in toxicity levels, likely related to differences in PAH proportions, were highlighted between fractions. The Arabian Light and Erika petrogenic fractions, containing a high proportion of alkylated PAHs and low molecular weight PAHs, were more toxic to Japanese medaka early life stages than the pyrolytic fraction. This was not supported by the toxic equivalency approach, which appeared unsuitable for assessing the toxicity of the three PAH fractions to fish early life stages. This study highlights the potential risks posed by environmental mixtures of alkylated and low molecular weight PAHs to early stages of fish development.

  1. Comparative survey of PAHs incidence in Portuguese traditional meat and blood sausages.

    Science.gov (United States)

    Roseiro, L C; Gomes, A; Patarata, L; Santos, C

    2012-06-01

    Sixteen polycyclic aromatic hydrocarbons (PAHs) in representative traditional sausages produced in "Trás-os-Montes" and "Alentejo", were determined. Light PAHs represented similar overall contents in both regions and showed close decreasing order patterns (ACY, PHE, FLR and NAP), irrespective of the product type considered. Amongst the carcinogenic/mutagenic PAHs analyzed (PAH8), both regions also had greater contents associated to BaA and CHR, with slightly higher values for the former compound in "Alentejo" and, oppositely, for the later in "Trás-os-Montes". However, their quantitative comparison showed that the general mean total PAH content found in "Trás-os-Montes" was almost 3-fold higher than in similar products from "Alentejo" and this factor was about 8-fold superior when the PAH8 and PAH4 indicators were compared, expressing benzo[a]pyrene toxic equivalencies (BaPE), 15 times (total mean toxicity), 34 times (PAH8) and 9 times (PAH4) higher. In general terms, the mean BaP content of all analyzed samples from "Alentejo" was 0.41 μg kg(-1). Differently that value in "Trás-os-Montes" reached 3.57 μg kg(-1), expressing concerning average contents of 5.35, 5.87 and 4.51 μg kg(-1) in Chouriço de Carne, Moura and Salpicão sausages, respectively. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Biomonitoring of PAHs by using Quercus ilex leaves: Source diagnostic and toxicity assessment

    Science.gov (United States)

    De Nicola, Flavia; Claudia, Lancellotti; MariaVittoria, Prati; Giulia, Maisto; Anna, Alfani

    2011-03-01

    Quercus ilex L. leaves were sampled at nineteen urban sites and two remote sites in order to evaluate PAH contamination degree. One-, two- and three-year-old leaves were collected and leaf lipid content was measured to investigate the influence of leaf age and lipids in PAH accumulation. Some PAH diagnostic ratios, such as Ant/Ant + Phen, Flt/Flt + Pyr, B[a]A/B[a]A + Crys and IP/IP + B[g,h,i]P, were calculated. The results suggest that Q. ilex leaves are effective biomonitors of PAH air contamination: in fact, a great PAH accumulation in leaves from the urban areas, until 30-time higher compared to those from the remote sites, has been observed. At each site, the similar total PAH concentrations in leaves of different age, probably due to a canopy effect, indicate an ability of all leaf age classes to monitor local PAH concentrations in air, remarking practical implications for air biomonitoring. The findings suggest that PAH adsorption in Q. ilex leaves does not result limited by leaf lipid content. Moreover, this study demonstrates the source-diagnostic potential of Q. ilex leaves, because, in particular, the Flt/Flt + Pyr and IP/IP + B[g,h,i]P ratios indicate vehicular traffic as the main source of PAHs in the urban areas and wood combustion in the remote areas. Moreover, to distinguish biomass combustion source, a promising tracer PAH as DB[a,h]A could be used. The high contribution of DB[a,h]A to total PAH concentrations at the remote sites determines a high carcinogenic potential in this area, similar to that calculated for the urban area where the carcinogenic PAH concentrations in absolute values are often higher.

  3. Development of methods for determination of PAH based on measured CO-content; Metodutveckling foer indirekt bestaemning av PAH-halt utgaaende fraan maett momentan CO-halt

    Energy Technology Data Exchange (ETDEWEB)

    Ingman, Rolf; Schuster, Robert [AaF Energikonsult Stockholm AB, Stockholm (Sweden)

    2001-02-01

    The aim of the project 'Development of methods for determination of PAH based on measured CO-content' is to investigate the possibility to develop a method for continuous optimisation of NO{sub x}-emissions by decreased air ratio, without significant increase of polyaromatic hydrocarbons such as PAH. The general idea has been to find a indirect online method to predict the emissions of heavier hydrocarbons by: - creating a correlation between the content of CO and PAH, - controlling the air ratio by the CO-content, and - integrating the calculated PAH-content from CO-content. Today many boilers are operated with a low air ratio to minimise the NO{sub x} content and the NO{sub x}-fee. A low ratio increases the risk of high CO contents in the flue gas as well as increased contents of VOC and PAH. Other boilers are operated with high air ratios in order to minimise the CO content, which in some cases will result in unnecessary high NO{sub x} emissions. One of the main difficulties in optimising the air ratio to the most environmental friendly level is the lack of a suitable and well proven PAH instrument. There are today no available instruments for instantaneous and continuous measurement of PAH. PAH is normally measured as an average value during a period of at least one hour. It is not possible to detect short peaks. The development of the CO-method has been based on data from a CFB-boiler in Korsta in Sundsvall (Vaermeforskrapport 541). The data shows a clear correlation between THC and CO. The correlation seems to be mostly dependent of moisture content and load. The development presented in the report shows that it is possible to find a method to predict the PAH content from the CO-content in the flue gas. The next phase aims to improve and implement the method, by measurements and adaptation in a plant. The practical use of the method is as a tool to optimise the emission of CO, NO{sub x}, THC and PAH and/or to predict the PAH-emission during

  4. PAHs pollution from traffic sources in air of Hangzhou, China: trend and influencing factors.

    Science.gov (United States)

    Zhu, Li-Zhong; Wang, Jing

    2005-01-01

    PAHs pollution in air of arterial roads was investigated from October 1998 to October 2001 in Hangzhou, China. The results showed that sigma10 PAHs was 13-36 microg/m3, among which, BaP, a strong carcinogenic kind ranged from 0.034 microg/m3 to 0.12 microg/m3. PAHs pollutions in four seasons were winter > autumn > spring-summer. The annual averages of sigmaPAHs concentration were 25 microg/m3 for 1999, 28 microg/m3 for 2000, and 29 microg/m3 for 2001, respectively. Leaded gasoline was banned in December 1998 in Hangzhou, thus comparative measurements with PAHs in leaded and lead-free gasoline powered motor exhausts made it certain that the use of lead-free gasoline leaded to a heavier PAHs pollution in roadside air from December, 1998, in China, and sigmaPAHs in air samples after the lead-banning were more than twice of that in samples before the action. For the large contribution of vehicle discharge to air pollution in roadside, further research was performed to suggest the factors influencing PAHs distribution in vehicle exhaust in order to control air pollution effectively. Compared to gasoline engines, emissions from diesel engines were less toxic, although they might produce more PAHs. Of the same vehicular and oil type, automobiles of longer mileages produced more toxic PAHs. PAHs distributions in the vehicular exhausts were related to the oil type. Large difference was found in the abundance of 3-, 5- and 6-ring PAHs between exhausts from gasoline and diesel oil engines. Diesel oil engines produced relative lighter PAHs such as NAPH, ACEN, FLUOR, while gasoline engines emitted heavier kinds such as BkF, IN and BP. The automobile produced more PAHs with the increase of mileage especially FLUR, PY, BaP, BP. Some significant ratios for traffic source in Hangzhou such as PHEN/AN, FLUR/PY, IN/BP were 0.50-4.3, 0.58-7.4, 0.51-1.5, respectively. A source fingerprint for vehicle exhausts of a mixture of vehicle and oil types in the city district for light

  5. Contamination characteristics and source apportionment of methylated PAHs in agricultural soils from Yangtze River Delta, China

    International Nuclear Information System (INIS)

    Chen, Weixiao; Wu, Xinyi; Zhang, Haiyun; Sun, Jianteng; Liu, Wenxin; Zhu, Lizhong; Li, Xiangdong; Tsang, Daniel C.W.; Tao, Shu; Wang, Xilong

    2017-01-01

    Alkylated PAHs (APAHs) have been shown to be more toxic and persistent than their non-alkylated parent compounds. However, little is known about the extent of soil contamination by these pollutants. To help understand agricultural soil pollution by these compounds at a regional scale, a total of 18 methylated PAHs (MPAHs, a major class of APAHs) in 243 soil samples were analyzed. These soil samples were collected from 11 sites in the Yangtze River Delta (YRD) region, a representative fast developing area in China. The total concentration of MPAHs (∑18MPAHs) ranged from 5.5 to 696.2 ng/g dry soil, with methylnaphthalenes (M-NAPs) and methylphenanthrenes (M-PHEs) accounting for more than 70% of the compositional profile. Relatively high concentrations of ∑18MPAHs were found in Jiaxing and Huzhou areas of Zhejiang province, as well as on the border between the cities of Wuxi and Suzhou. Different MPAH groups showed dissimilar spatial distribution patterns. The spatial distribution of lower molecular weight MPAHs was related to agricultural straw burning and emissions/depositions from industrial activities, whereas that of higher molecular weight MPAHs was much more a function of the total organic carbon (TOC) content of soil. Although coal, biomass (crop straw and wood), and petroleum combustion were identified to be the major emission sources for most of the sampling sites, the areas with relatively severe pollution with ∑18MPAHs resulted from the localized hotspots of petroleum leakage. Isomeric MPAHs with methyl group substituted at 2- (β) position exhibited significantly higher concentrations than those substituted at 1- (α) position. Results of this work help to understand soil pollution by MPAHs, and are useful for designing effective strategies for pollution control so as to ensure food safety in areas with fast economic growth. - Highlights: • Several 2–4 rings methyl-PAHs were investigated in soils from Yangtze River Delta. • Higher levels of

  6. Indoor PAHs at schools, homes and offices in Rome, Italy

    Science.gov (United States)

    Romagnoli, P.; Balducci, C.; Perilli, M.; Gherardi, M.; Gordiani, A.; Gariazzo, C.; Gatto, M. P.; Cecinato, A.

    2014-08-01

    Indoor and outdoor concentrations of polycyclic aromatic hydrocarbons (PAHs) associated with PM2.5 particles were monitored in three microenvironments (schools, homes and offices) in the city of Rome, Italy, between winter 2011 and summer 2012. Molecular signatures and indoor/outdoor concentration ratios of PAHs were investigated, with special emphasis on carcinogenic congeners. At indoor locations, total PAHs ranged, on average, from 1.8 to 8.4 ng/m3 in winter and from 0.30 to 1.35 ng/m3 in spring/summer. Outdoors, total PAH concentrations were found to reach 6.3-17.9 ng/m3 in winter and 0.42-1.74 ng/m3 in spring-summer. Indoors, the concentration of benzo[a]pyrene (BaP) was as high as 1.1 ng/m3 in winter and below 0.1 ng/m3 in the warm season, independently of site type; the yearly average remained below the European guideline value. The indoor/outdoor concentration ratios of individual compounds were lower than one for most of congeners, suggesting that outdoor sources were predominant. Nonetheless, the percentages of PAH compounds changed with sites and seasons; in particular, in spring/summer, the concentration of BaP at our sites was more than twice that recorded at the regional network stations.

  7. Source apportionment of polycyclic aromatic hydrocarbons (PAHs) in sediments from Khuzestan province, Iran

    DEFF Research Database (Denmark)

    Lübeck, Josephine; Poulsen, Kristoffer Gulmark; Knudsen, Sofie B.

    2016-01-01

    of polycyclic aromatic hydrocarbon (PAH) pollution. A four-component principal component analysis (PCA) model was obtained. While principal component 1 (PC1) was related to the total concentration of PAHs, the remaining PCs described three distinct sources: PC2 and PC3 collectively differentiate between...

  8. Effects of vehicle type and fuel quality on real world toxic emissions from diesel vehicles

    Science.gov (United States)

    Nelson, Peter F.; Tibbett, Anne R.; Day, Stuart J.

    Diesel vehicles are an important source of emissions of air pollutants, particularly oxides of nitrogen (NO x), particulate matter (PM), and toxic compounds with potential health impacts including volatile organic compounds (VOCs) such as benzene and aldehydes, and polycyclic aromatic hydrocarbons (PAHs). Current developments in engine design and fuel quality are expected to reduce these emissions in the future, but many vehicles exceed 10 years of age and may make a major contribution to urban pollutant concentrations and related health impacts for many years. In this study, emissions of a range of toxic compounds are reported using in-service vehicles which were tested using urban driving cycles developed for Australian conditions. Twelve vehicles were chosen from six vehicle weight classes and, in addition, two of these vehicles were driven through the urban drive cycle using a range of diesel fuel formulations. The fuels ranged in sulphur content from 24 to 1700 ppm, and in total aromatics from 7.7 to 33 mass%. Effects of vehicle type and fuel composition on emissions are reported. The results show that emissions of these toxic species were broadly comparable to those observed in previous dynamometer and tunnel studies. Emissions of VOCs and smaller PAHs such as naphthalene, which are derived largely from the combustion process, appear to be related, and show relatively little variability when compared with the variability in emissions of aldehydes and larger PAHs. In particular, aldehyde emissions are highly variable and may be related to engine operating conditions. Fuels of lower sulphur and aromatic content did not have a significant influence on emissions of VOCs and aldehydes, but tended to result in lower emissions of PAHs. The toxicity of vehicle exhaust, as determined by inhalation risk and toxic equivalency factor (TEF)-weighted PAH emissions, was reduced with fuels of lower aromatic content.

  9. Mobile sources of polycyclic aromatic hydrocarbons (PAH) and nitro-PAH: Results of samples collected in a roadway tunnel

    International Nuclear Information System (INIS)

    Benner, B.A. Jr.; Gordon, G.E.; Wise, S.A.

    1987-01-01

    A recent review article emphasized the need for further characterizations of the carbonaceous fraction of mobile source emissions, particularly with the impending removal of lead alkyl octane boosters and bromine-containing lead scavengers from regular leaded gasolines. The lead and bromine emitted from the combustion of these fuels have been used as tracers of mobile source emissions for a number of years. Single vehicle emission studies have shed light on the relationship between engine operating parameters and the chemical characteristics of the emissions but they are not suitable for use in source apportionment studies which require emission data from a large number of different vehicles. Air particulate samples collected near a busy highway or in a roadway tunnel would be more appropriate for use in estimating the mobile source contribution of organic compounds to a region. Suspended particle samples collected in a heavily-travelled roadway tunnel (Baltimore Harbor Tunnel, Baltimore, Maryland) were characterized for polycyclic aromatic hydrocarbons (PAH) and some nitro-PAH by gas and liquid chromatographic techniques. These samples included those collected on Teflon filters and on glass fiber filters for investigating any differences in samples collected on an inert (Teflon) and more reactive (glass-fiber) medium. All samples collected on Teflon were backed-up with polyurethane foam plugs (PUF) which trapped any inherent vapor-phase PAH as well as any compounds ''blown-off'' the particles during collection

  10. Leaching of PAHs from agricultural soils treated with oil shale combustion ash: an experimental study.

    Science.gov (United States)

    Jefimova, Jekaterina; Adamson, Jasper; Reinik, Janek; Irha, Natalya

    2016-10-01

    The present study focuses on the fate of polycyclic aromatic hydrocarbons (PAHs) in soils amended with oil shale ash (OSA). Leachability studies to assess the release of PAHs to the environment are essential before the application of OSA in agriculture. A quantitative estimation of the leaching of PAHs from two types of soil and two types of OSA was undertaken in this study. Two leaching approaches were chosen: (1) a traditional one step leaching scheme and (2) a leaching scheme with pretreatment, i.e.., incubation of the material in wet conditions imitating the field conditions, followed by a traditional leaching procedure keeping the total amount of water constant. The total amount of PAHs leached from soil/OSA mixtures was in the range of 15 to 48 μg/kg. The amount of total PAHs leached was higher for the incubation method, compared to the traditional leaching method, particularly for Podzolic Gleysols soil. This suggests that for the incubation method, the content of organic matter and clay minerals of the soil influence the fate of PAHs more strongly compared to the traditional leaching scheme. The amount of PAHs leached from OSA samples is higher than from soil/OSA mixtures, which suggests soils to inhibit the release of PAHs. Calculated amount of PAHs from experimental soil and OSA leaching experiments differed considerably from real values. Thus, it is not possible to estimate the amount of PAHs leached from soil/OSA mixtures based on the knowledge of the amount of PAHs leached from soil and OSA samples separately.

  11. Temporal variability of Polycyclic Aromatic Hydrocarbons (PAHs) in a receptor site of the Puebla-Tlaxcala Valley

    Science.gov (United States)

    Padilla, Z. V.; Torres, R.; Ruiz Suarez, L.; Molina, L. T.

    2013-05-01

    This contribution documents the presence and possible origin of PAHs, their temporal concentration patterns and correlations with other air pollutants in the so-called Puebla-Tlaxcala valley. This valley is located to the east of the Mexico City Metropolitan Area and is a very populated region which suffers of air pollution problems. Emission sources of PAHs include open burning, industrial boilers, automobiles and trucks, but vehicle emissions vary significantly depending on the use of: fuel, engine type and catalytic converter. An important emission source in the Puebla-Tlaxcala region is wood burning for cooking. Therefore, it is expected to have contributions of PAHS from this type of sources. PAHs measurements were performed in an air pollution semi-rural receptor site (Chipilo) southwest the City of Puebla, using an aerosol photoelectric sensor (PAS 2000 CE) to measure the concentration of PAHs and a diffuser charger (DC 2000 CE) to evaluate the active surface (DC) of the particles. The measuring period included March and April of 2012 during the ozne season in central Mexico. The use of these two sensors in parallel has been identified as a fingerprint technique to identify different types of particles from several combustion processes and is a useful tool to identify quantitatively the major source of emissions, as well as to describe thephysical and chemical characteristics of the particles. Correlations between PAHs and DC, with NOx and CO, together with an analysis of atmospheric transport may approximate the possible origin of these particles. The coefficient PAHs / DC associated with backward trajectory analysis represents a tool to identify potential areas of emission. The correlation between PAHs and NOx emissions reflects association with diesel combustion, while the correlation between PAHs and CO, the combustion of gasoline. The results show that vehicle emissions are the major source of PAHs with an associated increase in the concentration of

  12. SPATIAL VARIATIONS OF PAH PROPERTIES IN M17SW REVEALED BY SPITZER /IRS SPECTRAL MAPPING

    Energy Technology Data Exchange (ETDEWEB)

    Yamagishi, M. [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Chuo-ku, Sagamihara 252-5210 (Japan); Kaneda, H.; Ishihara, D.; Oyabu, S.; Suzuki, T.; Nishimura, A.; Kohno, M. [Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan); Onaka, T.; Ohashi, S. [Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Nagayama, T.; Matsuo, M. [Graduate School of Science and Engineering, Kagoshima University, 1-21-35 Korimoto, Kagoshima 890-0065 (Japan); Umemoto, T.; Minamidani, T.; Fujita, S. [Nobeyama Radio Observatory, National Astronomical Observatory of Japan (NAOJ), National Institutes of Natural Sciences (NINS), 462-2, Nobeyama, Minamimaki, Minamisaku, Nagano 384-1305 (Japan); Tsuda, Y., E-mail: yamagish@ir.isas.jaxa.jp [Graduate School of Science and Engineering, Meisei University, 2-1-1 Hodokubo, Hino, Tokyo 191-0042 (Japan)

    2016-12-20

    We present Spitzer /IRS mid-infrared spectral maps of the Galactic star-forming region M17 as well as IRSF/SIRIUS Br γ and Nobeyama 45 m/FOREST {sup 13}CO ( J = 1–0) maps. The spectra show prominent features due to polycyclic aromatic hydrocarbons (PAHs) at wavelengths of 6.2, 7.7, 8.6, 11.3, 12.0, 12.7, 13.5, and 14.2  μ m. We find that the PAH emission features are bright in the region between the H ii region traced by Br γ and the molecular cloud traced by {sup 13}CO, supporting that the PAH emission originates mostly from photo-dissociation regions. Based on the spatially resolved Spitzer /IRS maps, we examine spatial variations of the PAH properties in detail. As a result, we find that the interband ratio of PAH 7.7  μ m/PAH 11.3  μ m varies locally near M17SW, but rather independently of the distance from the OB stars in M17, suggesting that the degree of PAH ionization is mainly controlled by local conditions rather than the global UV environments determined by the OB stars in M17. We also find that the interband ratios of the PAH 12.0  μ m, 12.7  μ m, 13.5  μ m, and 14.2  μ m features to the PAH 11.3  μ m feature are high near the M17 center, which suggests structural changes of PAHs through processing due to intense UV radiation, producing abundant edgy irregular PAHs near the M17 center.

  13. Distribution, sources and ecological risk assessment of PAHs in surface sediments from the Luan River Estuary, China.

    Science.gov (United States)

    Zhang, Daolai; Liu, Jinqing; Jiang, Xuejun; Cao, Ke; Yin, Ping; Zhang, Xunhua

    2016-01-15

    The distribution, sources and risk assessment of 16 polycyclic aromatic hydrocarbons (PAHs) of surface sediments in the Luan River Estuary, China, have been investigated in the research. The results indicated that the total concentrations of 16 PAHs in surface sediments of the Luan River Estuary ranged from 5.1 to 545.1 ng g(-1)dw with a mean value of 120.8 ng g(-1)dw, which is relatively low in comparison with other estuaries around the world. The PAHs in the study area were mainly originated from pyrogenic sources. Besides, PAHs may be contaminated by petrogenic PAHs as indicated by the selected ratios of PAHs, the 2-tailed Pearson correlation analysis and principal components analysis at different sites. The result of the ecological risk assessment shows little negative effect for most individual PAHs in surface sediments of the Luan River Estuary, China. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Polycyclic aromatic hydrocarbons (PAH) in superficial water from a tropical estuarine system: Distribution, seasonal variations, sources and ecological risk assessment.

    Science.gov (United States)

    Santos, Ewerton; Souza, Michel R R; Vilela Junior, Antônio R; Soares, Laiane S; Frena, Morgana; Alexandre, Marcelo R

    2018-02-01

    This study aimed to evaluate the PAH distribution, sources, seasonal variations and ecological risk assessment in superficial water from the Japaratuba River, Brazil. PAH concentrations ranged from 4 to 119ngL -1 . It was observed that the PAH total concentrations and profiles showed significant differences when comparing the dry season (summer) with the rainy season (winter). Furthermore, most of the PAH originated from pyrogenic sources in the winter, whereas a mixture of sources was observed in the summer. PAH concentration levels found in this study were considered lower than those obtained in other estuarine systems. Ecological risk assessment was determined for individual PAH, based on the risk quotient (RQ) to evaluate the risk of aquatic biota's exposure to PAH. Results suggested that the Japaratuba River has achieved a moderate degree of ecological risk for high molecular weight, showing the importance of identifying these carcinogenic and mutagenic compounds in aquatic systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Evolution of bacterial community during bioremediation of PAHs in a coal tar contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Lors, C.; Ryngaert, A.; Perie, F.; Diels, L.; Damidot, D. [University of Lille, Lille (France)

    2010-11-15

    The monitoring of a windrow treatment applied to soil contaminated by mostly 2, 3- and 4-ring PAHs produced by coal tar distillation was performed by following the evolution of both PAH concentration and the bacterial community. Total and PAH-degrading bacterial community structures were followed by 165 rRNA PCR-DGGE in parallel with quantification by bacterial counts and 16 PAH measurements. Six months of biological treatment led to a strong decrease in 2-, 3- and 4-ring PAH concentrations (98, 97 and 82%, respectively). This result was associated with the activity of bacterial PAH-degraders belonging mainly to the Gamma proteobacteria, in particular the Enterobacteria and Pseudomonas genera which were detected over the course of the treatment. This group was considered to be a good bioindicator to determine the potential PAH biodegradation of contaminated soil. Conversely other species like the Beta proteobacteria were detected after 3 months when 2-, 3- and 4-ring PAHs were almost completely degraded. Thus presence of the Beta proteobacteria group could be considered a good candidate indicator to estimate the endpoint of biotreatment of this type of PAH contaminated soil.

  16. Power plant allocation in East Kalimantan considering total cost and emissions

    Science.gov (United States)

    Muslimin; Utomo, D. S.

    2018-04-01

    The fulfillment of electricity need in East Kalimantan is the responsibility of State Electricity Company/Perusahaan Listrik Negara (PLN). But PLN faces constraints in the lack of generating capacity it has. So the allocation of power loads in East Kalimantan has its own challenges. Additional power supplies from other parties are required. In this study, there are four scenarios tested to meet the electricity needs in East Kalimantan with the goal of minimizing costs and emissions. The first scenario is only by using PLN power plant. The second scenario is by combining PLN + Independent Power Producer (IPP) power plants. The third scenario is by using PLN + Rented power plants. The fourth scenario is by using PLN + Excess capacity generation. Numerical experiment using nonlinear programming is conducted with the help of the solver. The result shows that in the peak load condition, the best combination is scenario 2 (PLN + IPP). While at the lowest load condition, the cheapest scenario is PLN + IPP while the lowest emission is PLN + Rent.

  17. The Scale, Structure and Influencing Factors of Total Carbon Emissions from Households in 30 Provinces of China—Based on the Extended STIRPAT Model

    Directory of Open Access Journals (Sweden)

    Yong Wang

    2018-05-01

    Full Text Available Household carbon emissions are important components of total carbon emissions. The consumer side of energy-saving emissions reduction is an essential factor in reducing carbon emissions. In this paper, the carbon emissions coefficient method and Consumer Lifestyle Approach (CLA were used to calculate the total carbon emissions of households in 30 provinces of China from 2006 to 2015, and based on the extended Stochastic Impacts by Regression on Population, Affluence, and Technology (STIRPAT model, the factors influencing the total carbon emissions of households were analyzed. The results indicated that, first, over the past ten years, the energy and products carbon emissions from China’s households have demonstrated a rapid growth trend and that regional distributions present obvious differences. Second, China’s energy carbon emissions due to household consumption primarily derived from the residents’ consumption of electricity and coal; China’s products household carbon emissions primarily derived from residents’ consumption of the high carbon emission categories: residences, food, transportation and communications. Third, in terms of influencing factors, the number of households in China plays a significant role in the total carbon emissions of China’s households. The ratio of children 0–14 years old and gender ratio (female = 100 are two factors that reflect the demographic structure, have significant effects on the total carbon emissions of China’s households, and are all positive. Gross Domestic Product (GDP per capita plays a role in boosting the total carbon emissions of China’s households. The effect of the carbon emission intensity on total household carbon emissions is positive. The industrial structure (the proportion of secondary industries’ added value to the regional GDP has curbed the growth of total carbon emissions from China’s household consumption. The results of this study provide data to support the

  18. Polycyclic Aromatic Hydrocarbon (pah) In The Bulk Precipitation of The Seine Estuary, France

    Science.gov (United States)

    Motelay-Massei, A.; Ollivon, D.; Garban, B.; Chevreuil, M.

    The evolution of industry and the rising of population have resulted in deep changes in the quality of the environment. Nowadays much more often the attention of analysts is focused on the presence of organic pollutants in precipitation, such as polycyclic aromatic hydrocarbons or pesticides. Atmospheric inputs play a significant role in semivolatile chemicals cycling and alter so the hydrological cycle. PAHs are semi- volatile organic contaminants of great environmental concern because of their car- cinogenic properties. PAHs are produced primarily during incomplete combustion of fossil fuels and wood. Major sources of PAHs to urban atmosphere include au- tomobile traffic, home heating, municipal incinerators and industrial emissions. De- spite their production in urban and industrial sites, PAHs occur at high concentra- tions in rural areas due to their persistence and ability to be transported over long distances. The aim of this investigation was to obtain information about occurrence of organic trace components in precipitation in the Seine Estuary. It was also of in- terest to investigate the spatial and temporal variability of PAHs in the bulk (wet and dry) deposition occurring in the estuary region and to estimate PAH deposition flux on watershed (urban, industrial or rural). Precipitation samples were collected at four locations in the Seine Estuary: the first is an industrial site (Le Havre), two are urban sites (Rouen, representative of urban area influenced by heavy traffic and Notre-Dame de Gravenchon, near from an industrial center) and the last one is ru- ral (Evreux). Each of the sites is located close to a meteorological station. Sam- pling is performed weekly since March 2001. In our analytical conditions, "total PAH" includes 15 compounds: naphthalene (NAP), acenaphtene (ACE), phenanthrene (PHE), anthracene (ANT), fluoranthene (FTH), pyrene (PYR), benzo(a)anthracene (BaA), chrysene (CHR), benzo(b)fluoranthene (BbF), benzo(k)fluoranthene (Bk

  19. PAH volatilization following application of coal-tar-based pavement sealant

    Science.gov (United States)

    Van Metre, Peter C.; Majewski, Michael S.; Mahler, Barbara J.; Foreman, William T.; Braun, Christopher L.; Wilson, Jennifer T.; Burbank, Teresa L.

    2012-01-01

    Coal-tar-based pavement sealants, a major source of PAHs to urban water bodies, have recently been identified as a source of volatile PAHs to the atmosphere. We tracked the volatilization of PAHs for 1 year after application of a coal-tar-based pavement sealant by measuring gas-phase PAH concentrations above the pavement surface and solid-phase PAH concentrations in sealant scraped from the surface. Gas-phase concentrations at two heights (0.03 and 1.28 m) and wind speed were used to estimate volatilization flux. The sum of the concentrations of eight frequently detected PAHsPAH8) in the 0.03-m sample 1.6 h after application (297,000 ng m-3) was about 5000 times greater than that previously reported for the same height above unsealed parking lots (66 ng m-3). Flux at 1.6 h after application was estimated at 45,000 μg m-2 h-1 and decreased rapidly during the 45 days after application to 160 μg m-2 h-1. Loss of PAHs from the adhered sealant also was rapid, with about a 50% decrease in solid-phase ΣPAH8 concentration over the 45 days after application. There was general agreement, given the uncertainties, in the estimated mass of ΣPAH8 lost to the atmosphere on the basis of air sampling (2–3 g m-2) and adhered sealant sampling (6 g m-2) during the first 16 days after application, translating to a loss to the atmosphere of one-quarter to one-half of the PAHs in the sealcoat product. Combining the estimated mass of ΣPAH8 released to the atmosphere with a national-use estimate of coal-tar-based sealant suggests that PAH emissions from new coal-tar-based sealcoat applications each year (~1000 Mg) are larger than annual vehicle emissions of PAHs for the United States.

  20. Source apportionment of atmospheric polycyclic aromatic hydrocarbons (PAHs) in Palm Beach County, Florida.

    Science.gov (United States)

    Afshar-Mohajer, Nima; Wilson, Christina; Wu, Chang-Yu; Stormer, James E

    2016-04-01

    Due to concerns about adverse health effects associated with inhalation of atmospheric polycyclic aromatic hydrocarbons (PAHs), 30 ambient air samples were obtained at an air quality monitoring station in Palm Beach County, Florida, from March 2013 to March 2014. The ambient PAH concentration measurements and fractional emission rates of known sources were incorporated into a chemical mass balance model, CMB8.2, developed by EPA, to apportion contributions of three major PAH sources including preharvest sugarcane burning, mobile vehicles, and wildland fires. Strong association between the number of benzene rings and source contribution was found, and mobile vehicles were identified to be the prevailing source (contribution≥56%) for the observed PAHs concentration with lower molecular weights (four or fewer benzene rings) throughout the year. Preharvest sugarcane burning was the primary contributing source for PAHs with relatively higher molecular weights (five or more benzene rings) during the sugarcane burning season (from October to May of the next year). Source contribution of wildland fires varied among PAH compounds but was consistently lower than for sugarcane burning during the sugarcane harvest season. Determining the major sources responsible for ground-level PAHs serves as a tool to improving management strategies for PAH emitting sources and a step toward better protection of the health of residents in terms of exposure to PAHs. The results obtain insight into temporal dominance of PAH polluting sources for those residential areas located near sugarcane burning facilities and have implications beyond Palm Beach County, in areas with high concerns of PAHs and their linked sources. Source apportionment of atmospheric polycyclic hydrocarbons (PAHs) in Palm Beach County, Florida, meant to estimate contributions of major sources in PAH concentrations measured at Belle Glade City of Palm Beach County. Number of benzene rings was found to be the key parameter

  1. Coal-tar-based sealcoated pavement: a major PAH source to urban stream sediments.

    Science.gov (United States)

    Witter, Amy E; Nguyen, Minh H; Baidar, Sunil; Sak, Peter B

    2014-02-01

    We used land-use analysis, PAH concentrations and assemblages, and multivariate statistics to identify sediment PAH sources in a small (~1303 km(2)) urbanizing watershed located in South-Central, Pennsylvania, USA. A geographic information system (GIS) was employed to quantify land-use features that may serve as PAH sources. Urban PAH concentrations were three times higher than rural levels, and were significantly and highly correlated with combined residential/commercial/industrial land use. Principal components analysis (PCA) was used to group sediments with similar PAH assemblages, and correlation analysis compared PAH sediment assemblages to common PAH sources. The strongest correlations were observed between rural sediments (n = 7) and coke-oven emissions sources (r = 0.69-0.78, n = 5), and between urban sediments (n = 22) and coal-tar-based sealcoat dust (r = 0.94, n = 47) suggesting that coal-tar-based sealcoat is an important urban PAH source in this watershed linked to residential and commercial/industrial land use. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Dry Deposition of Polycyclic Aromatic Hydrocarbons (PAHs) at a Suburban Site in Beijing, China

    Science.gov (United States)

    Zhang, Xincheng; Wang, Weiyu; Zhu, Xianlei

    2017-04-01

    A great amount of polycyclic aromatic hydrocarbons (PAHs) have been generated by industrial production, waste incineration and landfill, traffic and road dust etc. They are emitted into atmosphere and afterwards enter into water body and soil through deposition, resulting in wide distribution of PAHs in environment. However, the dry deposition of PAHs from atmosphere has not been well studied, especially in the aspects of its characteristics, environmental and health effects, sources and mechanism. This study measured PAHs dry deposition in the northwest suburban area of Beijing. Dry deposition samples (i.e. dustfall samples) were collected at the sampling site located in China University of Petroleum - Beijing in 2012-2016. And PAHs in the samples were determined by GC/MS. The dry deposition flux of 16 US EPA priority PAHsPAH16) was 2.58 μg/(m^2·d), which was lower than those in other regions of North China. Its seasonal variability was more significant than annual variability (p spring > autumn > summer. The amount of ΣPAH16 removed from the atmosphere by dry deposition process accounted for only 1.2% of their emissions, indicating that the atmosphere self-purification capacity was quite limited and emission reduction measures would play a key role in controlling PAHs air pollution. However, PAHs dry deposition would deteriorate soil quality since the content of ΣPAH16 in dustfall was 1-2 orders of magnitude higher than that in soil in the same area. Dermal exposure resulting from PAHs dry deposition was not the major route. The sources of PAHs dry deposition varied with seasons. The profile and specific ratios of PAHs showed that in winter, domestic coal combustion was the main source of PAHs with the contribution up to 77%; in spring and summer, the impact of coal combustion decreased and the contribution of vehicle exhaust increased to 30% - 45%; in fall, in addition to coal combustion and vehicle exhaust, the impact of biomass burning was observed

  3. Concentration and source identification of polycyclic aromatic hydrocarbons (PAHs) in PM10 of urban, industrial and semi-urban areas in Malaysia

    Science.gov (United States)

    Jamhari, Anas Ahmad; Sahani, Mazrura; Latif, Mohd Talib; Chan, Kok Meng; Tan, Hock Seng; Khan, Md Firoz; Mohd Tahir, Norhayati

    2014-04-01

    Particulate matter (PM10) associated with polycyclic aromatic hydrocarbons (PAHs) in ambient air were determined at two sites within the Klang Valley, Kuala Lumpur (urban, KL) and Petaling Jaya (industrial, PJ), and one site outside the Klang Valley, Bangi (semi-urban, BG). This study aimed to determine the concentration and distribution of PAHs in PM10 and the source of origin through principal component analysis (PCA) and diagnostic ratio analysis. This study also assessed the health risk from exposure to airborne BaPeq. PM10 samples were collected on glass fiber filter paper using a High Volume Sampler (HVS) for 24 h between September 2010 and April 2011. The filter papers with PM10 were extracted using dichloromethane-methanol (3:1), and analysis of 16 USEPA priority PAHs was determined using gas chromatography with mass spectra (GC-MS). Health risk assessment was estimated using toxic equivalency factors (TEFs) and incremental lifetime cancer risk (ILCR) which quantitatively estimate the exposure risk for age specific group. The results showed that the total PAHs concentrations throughout seasonal monsoons for KL, PJ and BG ranged from 1.33 ng m-3 to 2.97 ng m-3, 2.24 ng m-3 to 4.84 ng m-3 and 1.64 ng m-3 to 3.45 ng m-3 respectively. More than 80% of total PAHs consisted of 5-ring and 6-ring PAHs such as benzo[a]pyrene (BaP), indeno[1,2,3-cd]pyrene (IcP), benzo[b]fluoranthene (BbF), benzo[k]fluoranthene (BkF) and benzo[g,h,i]perylene (BgP). The presence of benzo[g,h,i]perylene (BgP) with high concentration at all locations suggested a source indicator for traffic emission. PCA and diagnostic ratio analysis also suggested substantial contributions from traffic emission with minimal influence from coal combustion and natural gas emissions. The use of total BaPeq concentration provide a better estimation of carcinogenicity activities, where they contributed to more than 50% of the potential health risk. Health risk assessment showed that the estimated incremental

  4. Determination of total tin in canned food using inductively coupled plasma atomic emission spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Perring, Loic; Basic-Dvorzak, Marija [Department of Quality and Safety Assurance, Nestle Research Centre, P.O. Box 44, Vers chez-les-Blanc, 1000, Lausanne (Switzerland)

    2002-09-01

    Tin is considered to be a priority contaminant by the Codex Alimentarius Commission. Tin can enter foods either from natural sources, environmental pollution, packaging material or pesticides. Higher concentrations are found in processed food and canned foods. Dissolution of the tinplate depends on the of food matrix, acidity, presence of oxidising reagents (anthocyanin, nitrate, iron and copper) presence of air (oxygen) in the headspace, time and storage temperature. To reduce corrosion and dissolution of tin, nowadays cans are usually lacquered, which gives a marked reduction of tin migration into the food product. Due to the lack of modern validated published methods for food products, an ICP-AES (Inductively coupled plasma-atomic emission spectroscopy) method has been developed and evaluated. This technique is available in many laboratories in the food industry and is more sensitive than atomic absorption. Conditions of sample preparation and spectroscopic parameters for tin measurement by axial ICP-AES were investigated for their ruggedness. Two methods of preparation involving high-pressure ashing or microwave digestion in volumetric flasks were evaluated. They gave complete recovery of tin with similar accuracy and precision. Recoveries of tin from spiked products with two levels of tin were in the range 99{+-}5%. Robust relative repeatabilities and intermediate reproducibilities were <5% for different food matrices containing >30 mg/kg of tin. Internal standard correction (indium or strontium) did not improve the method performance. Three emission lines for tin were tested (189.927, 283.998 and 235.485 nm) but only 189.927 nm was found to be robust enough with respect to interferences, especially at low tin concentrations. The LOQ (limit of quantification) was around 0.8 mg/kg at 189.927 nm. A survey of tin content in a range of canned foods is given. (orig.)

  5. Association of plasma IL-6 and Hsp70 with HRV at different levels of PAHs metabolites.

    Directory of Open Access Journals (Sweden)

    Jian Ye

    Full Text Available Exposure to polycyclic aromatic hydrocarbons (PAHs is associated with reduced heart rate variability (HRV, a strong predictor of cardiovascular diseases, but the mechanism is not well understood.We hypothesized that PAHs might induce systemic inflammation and stress response, contributing to altered cardiac autonomic function.HRV indices were measured using a 3-channel digital Holter monitor in 800 coke oven workers. Plasma levels of interleukin-6 (IL-6 and heat shock protein 70 (Hsp70 were determined using ELISA. Twelve urinary PAHs metabolites (OH-PAHs were measured by gas chromatography-mass spectrometry.We found that significant dose-dependent relationships between four urinary OH-PAHs and IL-6 (all Ptrend<0.05; and an increase in quartiles of IL-6 was significantly associated with a decrease in total power (TP and low frequency (LF (Ptrend = 0.014 and 0.006, respectively. In particular, elevated IL-6 was associated in a dose-dependent manner with decreased TP and LF in the high-PAHs metabolites groups (all Ptrend<0.05, but not in the low-PAHs metabolites groups. No significant association between Hsp70 and HRV in total population was found after multivariate adjustment. However, increased Hsp70 was significantly associated with elevated standard deviation of NN intervals (SDNN, TP and LF in the low-PAHs metabolites groups (all Ptrend<0.05. We also observed that both IL-6 and Hsp70 significantly interacted with multiple PAHs metabolites in relation to HRV.In coke oven workers, increased IL-6 was associated with a dose-response decreased HRV in the high-PAHs metabolites groups, whereas increase of Hsp70 can result in significant dose-related increase in HRV in the low-PAHs metabolites groups.

  6. PAH in tea and coffee

    DEFF Research Database (Denmark)

    Duedahl-Olesen, Lene; Navarantem, Marin; Adamska, Joanna

    For food regulation in the European Union maximum limits on other foods than tea and coffee includes benzo[a]pyrene and the sum of PAH4 (sum of benzo[a]pyrene, chrysene, benz[a]anthracene and benzo[b]fluoranthene). This study includes analysis of the above mentioned PAH in both, tea leaves, coffee...... beans and ready-to-drink preparations. Compared to other food matrices (e.g. fish), the analytical methods were challenged by the hot water extracts. Preparation of tea includes roasting and drying of the tea leaves using combustion gases from burning wood, oil, or coal. These are responsible...... for accumulation of PAH in tea leaves. Different varieties of tea leaves were analyzed and highest concentrations were found in leaves from mate and black tea with maximum concentrations of 32 μg/kg for benzo[a]pyrene and 115 μg/kg for the sum of PAH4. Also, coffee beans are roasted during processing. However...

  7. Combustion Chamber Deposits and PAH Formation in SI Engines Fueled by Producer Gas from Biomass Gasification

    DEFF Research Database (Denmark)

    Ahrenfeldt, Jesper; Henriksen, Ulrik Birk; Schramm, Jesper

    2003-01-01

    Investigations were made concerning the formation of combustion chamber deposits (CCD) in SI gas engines fueled by producer gas. The main objective was to determine and characterise CCD and PAH formation caused by the presence of the light tar compounds phenol and guaiacol in producer gas from...... on filters and a sorbent was used for collection of vapour phase aromatic compounds. The filters and sorbent were analysed for polycyclic aromatic hydrocarbons (PAH) formed during combustion. The measurements showed that there was no significant increase in particulate PAH emissions due to the tar compounds...

  8. Removal of polycyclic aromatic hydrocarbons (PAHs) from industrial sludges in the ambient air conditions: automotive industry.

    Science.gov (United States)

    Karaca, Gizem; Tasdemir, Yucel

    2013-01-01

    Removal of polycyclic aromatic hydrocarbons (PAHs) existed in automotive industry treatment sludge was examined by considering the effects of temperature, UV, titanium dioxide (TiO2) and diethyl amine (DEA) in different dosages (i.e., 5% and 20%) in this study. Application of TiO2 and DEA to the sludge samples in ambient environment was studied. Ten PAH (Σ10 PAH) compounds were targeted and their average value in the sludge was found to be 4480 ± 1450 ng/g dry matter (DM). Total PAH content of the sludge was reduced by 25% in the ambient air environment. Meteorological conditions, atmospheric deposition, evaporation and sunlight irradiation played an effective role in the variations in PAH levels during the tests carried out in ambient air environment. Moreover, it was observed that when the ring numbers of PAHs increased, their removal rates also increased. Total PAH level did not change with the addition of 5% DEA and only 10% decreased with 5% TiO2 addition. PAH removal ratios were 8% and 32% when DEA (20%) and TiO2 (20%) were added, respectively. It was concluded that DEA was a weak photo-sensitizer yet TiO2 was effective only at 20% dosage.

  9. Development of methods for determination of PAH based on measured CO-content

    International Nuclear Information System (INIS)

    Ingman, Rolf; Schuster, Robert

    2001-02-01

    The aim of the project 'Development of methods for determination of PAH based on measured CO-content' is to investigate the possibility to develop a method for continuous optimisation of NO x -emissions by decreased air ratio, without significant increase of polyaromatic hydrocarbons such as PAH. The general idea has been to find a indirect online method to predict the emissions of heavier hydrocarbons by: - creating a correlation between the content of CO and PAH, - controlling the air ratio by the CO-content, and - integrating the calculated PAH-content from CO-content. Today many boilers are operated with a low air ratio to minimise the NO x content and the NO x -fee. A low ratio increases the risk of high CO contents in the flue gas as well as increased contents of VOC and PAH. Other boilers are operated with high air ratios in order to minimise the CO content, which in some cases will result in unnecessary high NO x emissions. One of the main difficulties in optimising the air ratio to the most environmental friendly level is the lack of a suitable and well proven PAH instrument. There are today no available instruments for instantaneous and continuous measurement of PAH. PAH is normally measured as an average value during a period of at least one hour. It is not possible to detect short peaks. The development of the CO-method has been based on data from a CFB-boiler in Korsta in Sundsvall (Vaermeforskrapport 541). The data shows a clear correlation between THC and CO. The correlation seems to be mostly dependent of moisture content and load. The development presented in the report shows that it is possible to find a method to predict the PAH content from the CO-content in the flue gas. The next phase aims to improve and implement the method, by measurements and adaptation in a plant. The practical use of the method is as a tool to optimise the emission of CO, NO x , THC and PAH and/or to predict the PAH-emission during continuous operation

  10. In situ treatment of soil contaminated with PAHs and phenols

    International Nuclear Information System (INIS)

    Sresty, G.; Dev, H.; Chang, J.; Houthoofd, J.

    1992-01-01

    The wood preserving industry uses more pesticides than any other industry worldwide. The major chemicals used are creosote, pentachlorophenol, and CCA (copper, chrome and arsenate). It is reported that between 415 to 550 creosoting operations within the United States consume approximately 454,000 metric tons of creosote annually. When properly used and disposed off, creosote does not appear to significantly threaten human health. However, due to improper disposal and spillage at old facilities, creosote and other wood preserving chemicals have found their way into surface soils. Active wood preserving sites generate an estimated 840 to 1530 dry metric tons of hazardous contaminated sludge annually, which is classified as KOOL. Creosote, obtained from coal tar, contains a large number of chemical components. The three main families of compounds represented in creosote are: polycyclic aromatic hydrocarbons (PAH), phenolic, and heterocyclic compounds. Creosote is composed of approximately 85% PAHs, 10% phenolic compounds and 5% heterocyclic compounds. There are approximately a total of 17 PAHs present in creosote. The four most prominent compounds belonging to the PAH family are naphthalene, 2-methylnaphthalene, phenanthrene, and anthracene. These four compounds represent approximately 52% of the total PAHs present in creosote. There are approximately 12 different phenolic compounds present in creosote among which phenol is the most abundant, representing 20% of the total phenolics. In addition, the various isomers of cresol represent about 20% and pentachlorophenol (PCP) represents 10% of the total phenolics. There are approximately 13 different heterocyclic compounds are the most abundant, representing approximately 70% of the total heterocyclics. All of these compounds possess toxic properties and some of them, for example, PCP, when subjected to high temperature environments are suspected precursors in the formation of dioxins

  11. PROPERTIES OF POLYCYCLIC AROMATIC HYDROCARBONS IN THE NORTHWEST PHOTON DOMINATED REGION OF NGC 7023. III. QUANTIFYING THE TRADITIONAL PROXY FOR PAH CHARGE AND ASSESSING ITS ROLE

    Energy Technology Data Exchange (ETDEWEB)

    Boersma, C.; Bregman, J.; Allamandola, L. J., E-mail: Christiaan.Boersma@nasa.gov [NASA Ames Research Center, MS 245-6, Moffett Field, CA 94035-0001 (United States)

    2015-06-10

    Polycyclic aromatic hydrocarbon (PAH) emission in the Spitzer/IRS spectral map of the northwest photon dominated region (PDR) in NGC 7023 is analyzed. Here, results from fitting the 5.2–14.5 μm spectrum at each pixel using exclusively PAH spectra from the NASA Ames PAH IR Spectroscopic Database (www.astrochem.org/pahdb/) and observed PAH band strength ratios, determined after isolating the PAH bands, are combined. This enables the first quantitative and spectrally consistent calibration of PAH charge proxies. Calibration is straightforward because the 6.2/11.2 μm PAH band strength ratio varies linearly with the ionized fraction (PAH ionization parameter) as determined from the intrinsic properties of the individual PAHs comprising the database. This, in turn, can be related to the local radiation field, electron density, and temperature. From these relations diagnostic templates are developed to deduce the PAH ionization fraction and astronomical environment in other objects. The commonly used 7.7/11.2 μm PAH band strength ratio fails as a charge proxy over a significant fraction of the nebula. The 11.2/12.7 μm PAH band strength ratio, commonly used as a PAH erosion indicator, is revealed to be a better tracer for PAH charge across NGC 7023. Attempting to calibrate the 12.7/11.2 μm PAH band strength ratio against the PAH hydrogen adjacency ratio (duo+trio)/solo is, unexpectedly, anti-correlated. This work both validates and extends the results from Paper I and Paper II.

  12. Cosmic PAHs: from infrared astronomy to laboratory astrophysics

    Science.gov (United States)

    Joblin, Christine

    2017-06-01

    Astronomers consider polycyclic aromatic hydrocarbons (PAHs) to be the smallest dust particles and they use their infrared emission features, the aromatic infrared bands (AIBs), as a diagnostic of physical conditions in regions of star formation from the small scales of protoplanetary disks to the large scales of galaxies. This topic has to face several obstacles. One is the lack of identification of specific PAH species. Another one is that the AIB features carry not only information on the chemical diversity of species but also on photophysical processes involved in the relaxation of PAHs after having been energized by the absorption of UV photons from stars. In this presentation, I will discuss how we can progress in the analysis of the observed AIB spectrum by addressing both the photophysics of isolated PAHs and the formation and evolution of these molecules in cosmic environments. This is achieved by the combination of astronomical models with detailed investigation of molecular processes. The study of these processes has stimulated the development of dedicated laboratory setups and theoretical simulations at the forefront of molecular physics. I will more specifically present the opening given by ERC Synergy project Nanocosmos and the perspectives with the coming James Webb telescope.

  13. PAHs molecules and heating of the interstellar gas

    Science.gov (United States)

    Verstraete, Laurent; Leger, Alain; Dhendecourt, Louis B.; Dutuit, O.; Defourneau, D.

    1989-01-01

    Until now it has remained difficult to account for the rather high temperatures seen in many diffuse interstellar clouds. Various heating mechanisms have been considered: photoionization of minor species, ionization of H by cosmic rays, and photoelectric effect on small grains. Yet all these processes are either too weak or efficient under too restricting conditions to balance the observed cooling rates. A major heat source is thus still missing in the thermal balance of the diffuse gas. Using photoionization cross sections measured in the lab, it was shown that in order to balance the observed cooling rates in cold diffuse clouds (T approx. 80 K) the PAHs would have to contain 15 percent of the cosmic abundance of carbon. This value does not contradict the former estimation of 6 percent deduced from the IR emission bands since this latter is to be taken as a lower limit. Further, it was estimated that the contribution to the heating rate due to PAH's in a warm HI cloud, assuming the same PAH abundance as for a cold HI cloud, would represent a significant fraction of the value required to keep the medium in thermal balance. Thus, photoionization of PAHs might well be a major heat source for the cold and warm HI media.

  14. Characteristics of PAHs in farmland soil and rainfall runoff in Tianjin, China.

    Science.gov (United States)

    Shi, Rongguang; Xu, Mengmeng; Liu, Aifeng; Tian, Yong; Zhao, Zongshan

    2017-10-14

    Rainfall runoff can remove certain amounts of pollutants from contaminated farmland soil and result in a decline in water quality. However, the leaching behaviors of polycyclic aromatic hydrocarbons (PAHs) with rainfall have been rarely reported due to wide variations in the soil compositions, rainfall conditions, and sources of soil PAHs in complex farmland ecosystems. In this paper, the levels, spatial distributions, and composition profiles of PAHs in 30 farmland soil samples and 49 rainfall-runoff samples from the Tianjin region in 2012 were studied to investigate their leaching behaviors caused by rainfall runoff. The contents of the Σ 16 PAHs ranged from 58.53 to 3137.90 μg/kg in the soil and 146.58 to 3636.59 μg/L in the runoff. In total, most of the soil sampling sites (23 of 30) were contaminated, and biomass and petroleum combustion were proposed as the main sources of the soil PAHs. Both the spatial distributions of the soil and the runoff PAHs show a decreasing trend moving away from the downtown, which suggested that the leaching behaviors of PAHs in a larger region during rainfall may be mainly affected by the compounds themselves. In addition, 4- and 5-ring PAHs are the dominant components in farmland soil and 3- and 4-ring PAHs dominate the runoff. Comparisons of the PAH pairs and enrichment ratios showed that acenaphthylene, acenaphthene, benzo[a]anthracene, chrysene, and fluoranthene were more easily transferred into water systems from soil than benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[ghi]perylene, and indeno[123-cd]pyrene, which indicated that PAHs with low molecular weight are preferentially dissolved due to their higher solubility compared to those with high molecular weight.

  15. Monitoring PAH contamination in water: Comparison of biological and physico-chemical tools

    International Nuclear Information System (INIS)

    Bourgeault, A.; Gourlay-Francé, C.

    2013-01-01

    The suitability of biological methods and chemical-based passive samplers to determine exposure to PAHs was tested by deploying zebra mussels and SPMDs along the Seine River over 11 months. The concentration of 13 PAHs was analyzed every month in both water and mussels. The sum of the PAH concentrations in mussels, initially at 299 ng g dry wt −1 , reached 2654, 3972 and 3727 ng g −1 at the end of exposure in the three sampling points taken through the river. The respective SPMD-available concentrations of TPAHs reached 9, 52 and 34 ng L −1 . Results showed seasonal variations of total PAH concentrations in the mussels, characterized by a decrease during spawning. The non-achievement of steady state concentration that was observed in mussels may be accounted for by the temporal variation of environmental concentrations. Thus, a bioaccumulation model based on kinetic rather than simple equilibrium partitioning was found to be more appropriate to describe PAH content in mussels. Moreover, biodynamic kinetic modeling proved useful to better understand the uptake and loss processes of pyrene. It clearly shows that these processes are markedly influenced by the biological state of the zebra mussels. The most realistic hypothesis is that the temporal variation of the biodynamic parameters may originate from a decrease of the mussels' metabolization of PAHs during spawning. Since SPMD passive samplers cannot integrate such biological factors, they are poor predictors of PAH bioavailability in mussels. - Highlights: • PAH contamination was monitored by deploying mussels and SPMDs over 11 months along the Seine River. • 5–6 ring PAHs which could not be quantified in spot samples, were measured in SPMDs. • PAH concentrations in the mussels decreased during spawning. • Temporal variation of bioaccumulated PAH may originate from a decrease of the mussels' metabolism during spawning. • Biodynamic model was allowed to explain the bioaccumulation

  16. Monitoring PAH contamination in water: Comparison of biological and physico-chemical tools

    Energy Technology Data Exchange (ETDEWEB)

    Bourgeault, A., E-mail: bourgeault@ensil.unilim.fr; Gourlay-Francé, C.

    2013-06-01

    The suitability of biological methods and chemical-based passive samplers to determine exposure to PAHs was tested by deploying zebra mussels and SPMDs along the Seine River over 11 months. The concentration of 13 PAHs was analyzed every month in both water and mussels. The sum of the PAH concentrations in mussels, initially at 299 ng g{sub dry} {sub wt}{sup −1}, reached 2654, 3972 and 3727 ng g{sup −1} at the end of exposure in the three sampling points taken through the river. The respective SPMD-available concentrations of TPAHs reached 9, 52 and 34 ng L{sup −1}. Results showed seasonal variations of total PAH concentrations in the mussels, characterized by a decrease during spawning. The non-achievement of steady state concentration that was observed in mussels may be accounted for by the temporal variation of environmental concentrations. Thus, a bioaccumulation model based on kinetic rather than simple equilibrium partitioning was found to be more appropriate to describe PAH content in mussels. Moreover, biodynamic kinetic modeling proved useful to better understand the uptake and loss processes of pyrene. It clearly shows that these processes are markedly influenced by the biological state of the zebra mussels. The most realistic hypothesis is that the temporal variation of the biodynamic parameters may originate from a decrease of the mussels' metabolization of PAHs during spawning. Since SPMD passive samplers cannot integrate such biological factors, they are poor predictors of PAH bioavailability in mussels. - Highlights: • PAH contamination was monitored by deploying mussels and SPMDs over 11 months along the Seine River. • 5–6 ring PAHs which could not be quantified in spot samples, were measured in SPMDs. • PAH concentrations in the mussels decreased during spawning. • Temporal variation of bioaccumulated PAH may originate from a decrease of the mussels' metabolism during spawning. • Biodynamic model was allowed to explain

  17. Characterizing Methane Emissions at Local Scales with a 20 Year Total Hydrocarbon Time Series, Imaging Spectrometry, and Web Facilitated Analysis

    Science.gov (United States)

    Bradley, Eliza Swan

    Methane is an important greenhouse gas for which uncertainty in local emission strengths necessitates improved source characterizations. Although CH4 plume mapping did not motivate the NASA Airborne Visible InfraRed Imaging Spectrometer (AVIRIS) design and municipal air quality monitoring stations were not intended for studying marine geological seepage, these assets have capabilities that can make them viable for studying concentrated (high flux, highly heterogeneous) CH4 sources, such as the Coal Oil Point (COP) seep field (˜0.015 Tg CH4 yr-1) offshore Santa Barbara, California. Hourly total hydrocarbon (THC) data, spanning 1990 to 2008 from an air pollution station located near COP, were analyzed and showed geologic CH4 emissions as the dominant local source. A band ratio approach was developed and applied to high glint AVIRIS data over COP, resulting in local-scale mapping of natural atmospheric CH4 plumes. A Cluster-Tuned Matched Filter (CTMF) technique was applied to Gulf of Mexico AVIRIS data to detect CH4 venting from offshore platforms. Review of 744 platform-centered CTMF subsets was facilitated through a flexible PHP-based web portal. This dissertation demonstrates the value of investigating municipal air quality data and imaging spectrometry for gathering insight into concentrated methane source emissions and highlights how flexible web-based solutions can help facilitate remote sensing research.

  18. PAH Baselines for Amazonic Surficial Sediments: A Case of Study in Guajará Bay and Guamá River (Northern Brazil).

    Science.gov (United States)

    Rodrigues, Camila Carneiro Dos Santos; Santos, Ewerton; Ramos, Brunalisa Silva; Damasceno, Flaviana Cardoso; Correa, José Augusto Martins

    2018-06-01

    The 16 priority PAH were determined in sediment samples from the insular zone of Guajará Bay and Guamá River (Southern Amazon River mouth). Low hydrocarbon levels were observed and naphthalene was the most representative PAH. The low molecular weight PAH represented 51% of the total PAH. Statistical analysis showed that the sampling sites are not significantly different. Source analysis by PAH ratios and principal component analysis revealed that PAH are primary from a few rate of fossil fuel combustion, mainly related to the local small community activity. All samples presented no biological stress or damage potencial according to the sediment quality guidelines. This study discuss baselines for PAH in surface sediments from Amazonic aquatic systems based on source determination by PAH ratios and principal component analysis, sediment quality guidelines and through comparison with previous studies data.

  19. Sources of polyaromatic hydrocarbons (PAH); Kildebestemmelse af polyaromatiske kulbrinter (PAH)

    Energy Technology Data Exchange (ETDEWEB)

    Egsgaard, H. [Forskningscenetr Risoe, Ald. for Plantebiologi og Biokemi (DK); Larsen, E. [Forskningscenter Risoe, Ald. for Optic og Fluid Dynamik (Denmark)

    2000-03-01

    Aromatic hydrocarbons including PAH compounds are thermally and chemically very stable compounds and are formed by gasification/pyrolysis of biomass. With reference to the tar compounds present in the produced gas from updraft gasifiers the sources responsible for the formation of naphthalene and poly-aromatic hydrocarbons have been investigated. The focus has been on thermal and oxidative conversions of compounds related to the lignin building blocks. Thus, phenols, 2-methoxy-phenols and 4-substituted-2-methoxy-phenols were investigated by introducing water solutions of the compounds into a continuos flow system operating in the temperature range 600-850 deg. C. The pyrolysis products were identified by GC/MS. The tar compounds reveal a well-defined and characteristic thermal transformation. Phenol is a strong source to naphthalene and indenes while 2-methoxyphenols are sources to aromatic oxo-compounds such as cinnamaldehyde. More complex systems are sources to higer PAH compounds. Thus, oligomers of phenol and 2-methoxyphenol give dibenzofuran and oligomers of isoeugenol are important sources to acenaphthylene. It is characteristic that the simple tar compounds investigated undergo loss of CO and hereby loss of the aromatic structure. The intermediary compounds are very reactive cyclo-pentadienes entering Diels-Alder reactions. The later products are transformed to aromatic compounds. The results may facilitate the determination of optimum conditions for updraft gasifiers and hence a reduction of PAH formation. (au)

  20. Comparison of 15N analysis by optical emission spectrometry and mass spectrometry for clinical studies during total parenteral nutrition

    International Nuclear Information System (INIS)

    Ragon, A.; Reynier, J.P.; Guiraud, G.

    1985-01-01

    During total and stable parenteral nutrition, a branched chain amino acid enriched solution containing [ 15 N]leucine was infused into a patient to determine the fate of the nitrogen administered through this formulation. Measurements of 15 N isotopic enrichments were performed on the same biological samples (urinary urea, total plasma proteins and albumin) by optical emission spectrometry (OES) and mass spectrometry (MS) to determine if OES with its specific advantages (cost, handling maintenance) constituted even with low enrichments a useful alternative technique to MS considered as the reference method. The results show that OES constituted a very useful analytical technique to obtain reliable information in clinical metabolic studies when low 15 N enrichments must be determined. (Auth.)

  1. Effect of fuel composition on poly aromatic hydrocarbons in particulate matter from DI diesel engine; Particulate chu no PAH ni oyobosu nenryo sosei no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, S; Tatani, T; Yoshida, H; Takizawa, H; Miyoshi, K; Ikebe, H [COSMO Research Institute, Tokyo (Japan)

    1997-10-01

    The effect of fuel composition on poly aromatic hydrocarbons (PAH) in particulate matter from DI diesel engine was investigated by using deeply desulfurized fuel and model fuel which properties are not interrelated. It was found that the deeply desulfurized fuel have effect on reducing PAH emissions. Furthermore, it was suggested that poly aromatics in the fuel affect PAH emissions and the influence of tri-aromatics in the fuel was promoted by the coexistence of mono-aromatics or naphthene. PAH formation scheme from each fuel component was proposed by chemical thermodynamic data. 4 refs., 8 figs., 3 tabs.

  2. A source mixing model to apportion PAHs from coal tar and asphalt binders in street pavements and urban aquatic sediments

    Energy Technology Data Exchange (ETDEWEB)

    Ahrens, M.J.; Depree, C.V. [National Institute of Water & Atmospheric Research, Hamilton (New Zealand)

    2010-12-15

    Present-day and more than 30 years old road and footpath pavements from Auckland, New Zealand were analysed for PAHs to test the hypothesis that coal tar based pavement binders contribute to unusually high PAH concentrations in adjacent stream and estuarine sediments Total PAH ({Sigma}{sub 28}PAH) concentrations in the dichloromethane-soluble fraction ('binder'), comprising 5-10% of pavement mass, were as high as 200 000 mg kg{sup -1}(10 000 mg kg{sup -1} in binder + aggregate) Older and deeper pavement layers were strongly pyrogenic, whereas pavement layers from recently sealed roads had a more petrogenic composition and more than 1000 times lower Sigma(28)PAH concentrations. Source identification analysis using three PAH isomer ratio pairs (benz(a)anthracene/(benz(a)anthracene + chrysene), benzo(a)pyrene/(benzo(a)pyrene + benzo(e)pyrene)), and indeno(1,2,3-cd)pyrene/(indeno(1,2,3-cd)pyrene + benzo(g,h,i)perylene) revealed low PAH (bitumen) pavements to have consistently lower isomer ratios than high PAH (coal tar) samples. A concentration-weighted mixing model, with coal tar and bitumen as source materials, explained more than 80% of the variance in isomer ratios and enveloped the entire PAH compositional and concentration range encountered PAH composition and concentrations in adjacent stream sediments ({gt} 15 mg kg{sup -1} dry weight) were consistent with diluted coal tar material as a principal PAH source. Due to the very high PAH concentrations of coal tar, a coal tar content of as little as 0.01% of total sediment mass can account for more than 90% of PAH concentrations in adjacent stream sediments.

  3. Avoiding total reduced sulfur (TRS) emissions from sodium sulfite pulping recovery processes

    International Nuclear Information System (INIS)

    Norman, J.C.; Sell, N.J.; Ciriacks, J.C.

    1990-01-01

    This paper reports that one of the current trends in paper-making with cellulose pulping is the use of high-yield processes. With yields greater than 65%, these processes include mechanical pulps (groundwood and thermomechanical pulps or TMP), and semichemical types (chemi-TMP or CTMP). Groundwood and TMP make up about 10% of North American pulp production. Semichemical pulp makes up about 7% and is mostly used for corrugating medium. High-yield pulping for linerboard, particularly using the alkaline sulfite process, is also likely to be used in the future. High-yield pulping is based primarily on the sulfite process using mostly sodium-based chemicals. A disadvantage of this process is the unavailability of a recovery system for the inorganic pulping chemicals. Generally, mills have not accepted any particular recovery system for this process. For this and other reasons, sulfite processes constitute only 3-4% of the total North American pulp production. If high-yield processes continue to increase in popularity, a sodium sulfite chemical recovery system will be needed. A number of chemical recovery systems have been developed in the past 30 years for sodium-based sulfite pulping processes, with most of the mills successfully using this process located in Scandinavia

  4. Total Particle Number Emissions from Modern Diesel, Natural Gas, and Hybrid Heavy-Duty Vehicles During On-Road Operation.

    Science.gov (United States)

    Wang, Tianyang; Quiros, David C; Thiruvengadam, Arvind; Pradhan, Saroj; Hu, Shaohua; Huai, Tao; Lee, Eon S; Zhu, Yifang

    2017-06-20

    Particle emissions from heavy-duty vehicles (HDVs) have significant environmental and public health impacts. This study measured total particle number emission factors (PNEFs) from six newly certified HDVs powered by diesel and compressed natural gas totaling over 6800 miles of on-road operation in California. Distance-, fuel- and work-based PNEFs were calculated for each vehicle. Distance-based PNEFs of vehicles equipped with original equipment manufacturer (OEM) diesel particulate filters (DPFs) in this study have decreased by 355-3200 times compared to a previous retrofit DPF dynamometer study. Fuel-based PNEFs were consistent with previous studies measuring plume exhaust in the ambient air. Meanwhile, on-road PNEF shows route and technology dependence. For vehicles with OEM DPFs and Selective Catalytic Reduction Systems, PNEFs under highway driving (i.e., 3.34 × 10 12 to 2.29 × 10 13 particles/mile) were larger than those measured on urban and drayage routes (i.e., 5.06 × 10 11 to 1.31 × 10 13 particles/mile). This is likely because a significant amount of nucleation mode volatile particles were formed when the DPF outlet temperature reached a critical value, usually over 310 °C, which was commonly achieved when vehicle speed sustained over 45 mph. A model year 2013 diesel HDV produced approximately 10 times higher PNEFs during DPF active regeneration events than nonactive regeneration.

  5. Quantitative determination of total cesium in highly active liquid waste by using liquid electrode plasma optical emission spectrometry.

    Science.gov (United States)

    Do, Van-Khoai; Yamamoto, Masahiko; Taguchi, Shigeo; Takamura, Yuzuru; Surugaya, Naoki; Kuno, Takehiko

    2018-06-01

    A sensitive analytical method for determination of total cesium (Cs) in highly active liquid waste (HALW) by using modified liquid electrode plasma optical emission spectrometry (LEP-OES) is developed in this study. The instrument is modified to measure radioactive samples in a glove box. The effects of important factors, including pulsed voltage sequence and nitric acid concentration, on the emission of Cs are investigated. The limit of detection (LOD) and limit of quantification (LOQ) are 0.005 mg/L and 0.02 mg/L, respectively. The achieved LOD is one order lower than that of recently developed spectroscopic methods using liquid discharge plasma. The developed method is validated by subjecting a simulated HALW sample to inductively coupled plasma mass spectrometry (ICP-MS). The recoveries obtained from a spike-and-recovery test are 96-102%, implying good accuracy. The method is successfully applied to the quantification of Cs in a real HALW sample at the Tokai reprocessing plant in Japan. Apart from dilution and filtration of the HALW sample, no other pre-treatment process is required. The results agree well with the values obtained using gamma spectrometry. The developed method offers a reliable technique for rapid analysis of total Cs in HALW samples. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Human health risk due to variations in PM10-PM2.5 and associated PAHs levels

    Science.gov (United States)

    Sosa, Beatriz S.; Porta, Andrés; Colman Lerner, Jorge Esteban; Banda Noriega, Roxana; Massolo, Laura

    2017-07-01

    WHO (2012) reports that chronic exposure to air pollutants, including particulate matter (PM), causes the death of 7 million people, constituting the most important environmental risk for health in the world. IARC classifies contaminated outdoor air as carcinogenic, Group 1 category. However, in our countries there are few studies regarding air pollution levels and possible associated effects on public health. The current study determined PM and associated polycyclic aromatic hydrocarbons (PAHs) levels in outdoor air, identified their possible emission sources and analysed health risks in the city of Tandil (Argentina). PM10 and PM2.5 samples were collected using a low volume sampler (MiniVol TAS) in three areas: city centre, industrial and residential. Concentrations were determined by gravimetric methods and the content of the US EPA 16 priority PAHs was found by high performance liquid chromatography (HPLC). Description of the main emission sources and selection of monitoring sites resulted from spatial analysis and the IVE (International Vehicle Emissions) model was used in the characterisation of the traffic flow. Median values of 35.7 μgm-3 and 9.6 μgm-3 in PM10 and PM2.5 respectively and characteristic profiles were found for each area. Local values PAHs associated to PM10 and PM2.5, in general, were lower than 10ngm-3. The estimated Unit Risk for the three areas exceeds US EPA standards (9 × 10-5). The number of deaths attributable to short term exposure to outdoor PM10 was 4 cases in children under 5 years of age, and 21 cases in total population, for a relative risk of 1.037.

  7. Increased zooplankton PAH concentrations across hydrographic fronts in the East China Sea.

    Science.gov (United States)

    Hung, Chin-Chang; Ko, Fung-Chi; Gong, Gwo-Ching; Chen, Kuo-Shu; Wu, Jian-Ming; Chiang, Hsin-Lun; Peng, Sen-Chueh; Santschi, Peter H

    2014-06-15

    The Changjiang has transported large quantities of polycyclic aromatic hydrocarbons (PAHs) to the East China Sea (ECS), but information of these pollutants in zooplankton is limited. To understand PAHs pollution in zooplankton in the ECS, total concentrations of PAHs in zooplankton from surface waters were measured. Values of PAHs ranged from 2 to 3500 ng m(-3) in the ECS, with highest PAHs levels located at the salinity front between the Changjiang Diluted Water (CDW) and the mid-shelf waters. In contrast, concentrations of zooplankton PAHs in the mid-shelf and outer-shelf waters were significantly lower (2-23 ng m(-3)) than those in the CDW. These results demonstrate that PAHs are conspicuously accumulated in zooplankton at the salinity front between the CDW and the mid-shelf waters. These higher levels of PAHs in zooplankton at the salinity front may be further biomagnified in marine organisms of higher trophic levels through their feeding activities. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. Polycyclic aromatic hydrocarbons (PAH) formation from the pyrolysis of different municipal solid waste fractions.

    Science.gov (United States)

    Zhou, Hui; Wu, Chunfei; Onwudili, Jude A; Meng, Aihong; Zhang, Yanguo; Williams, Paul T

    2015-02-01

    The formation of 2-4 ring polycyclic aromatic hydrocarbons (PAH) from the pyrolysis of nine different municipal solid waste fractions (xylan, cellulose, lignin, pectin, starch, polyethylene (PE), polystyrene (PS), polyvinyl chloride (PVC), and polyethylene terephthalate (PET)) were investigated in a fixed bed furnace at 800 °C. The mass distribution of pyrolysis was also reported. The results showed that PS generated the most total PAH, followed by PVC, PET, and lignin. More PAH were detected from the pyrolysis of plastics than the pyrolysis of biomass. In the biomass group, lignin generated more PAH than others. Naphthalene was the most abundant PAH, and the amount of 1-methynaphthalene and 2-methynaphthalene was also notable. Phenanthrene and fluorene were the most abundant 3-ring PAH, while benzo[a]anthracene and chrysene were notable in the tar of PS, PVC, and PET. 2-ring PAH dominated all tar samples, and varied from 40 wt.% to 70 wt.%. For PS, PET and lignin, PAH may be generated directly from the aromatic structure of the feedstock. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Coal-tar-based parking lot sealcoat: An unrecognized source of PAH to settled house dust

    Science.gov (United States)

    Mahler, B.J.; Van Metre, P.C.; Wilson, J.T.; Musgrove, M.; Burbank, T.L.; Ennis, T.E.; Bashara, T.J.

    2010-01-01

    Despite much speculation, the principal factors controlling concentrations of polycyclic aromatic hydrocarbons (PAH) in settled house dust (SHD) have not yet been identified. In response to recent reports that dust from pavement with coaltar-based sealcoat contains extremely high concentrations of PAH, we measured PAH in SHD from 23 apartments and in dust from their associated parking lots, one-half of which had coal-tar-based sealcoat (CT). The median concentration of total PAH (T-PAH) in dust from CT parking lots (4760 ??g/g, n = 11) was 530 times higher than that from parking lots with other pavement surface types (asphalt-based sealcoat, unsealed asphalt, concrete [median 9.0 ??g/g, n = 12]). T-PAH in SHD from apartments with CT parking lots (median 129 ??g/g) was 25 times higher than that in SHD from apartments with parking lots with other pavement surface types (median 5.1 ??g/g). Presence or absence of CT on a parking lot explained 48% of the variance in log-transformed T-PAH in SHD. Urban land-use intensity near the residence also had a significant but weaker relation to T-PAH. No other variables tested, including carpeting, frequency of vacuuming, and indoor burning, were significant. ?? 2010 American Chemical Society.

  10. Properties of polycyclic aromatic hydrocarbons in the northwest photon dominated region of NGC 7023. II. Traditional PAH analysis using k-means as a visualization tool

    International Nuclear Information System (INIS)

    Boersma, C.; Bregman, J.; Allamandola, L. J.

    2014-01-01

    Polycyclic aromatic hydrocarbon (PAH) emission in the Spitzer-IRS spectral map of the northwest photon dominated region (PDR) in NGC 7023 is analyzed using the 'traditional' approach in which the PAH bands and plateaus between 5.2-19.5 μm are isolated by subtracting the underlying continuum and removing H 2 emission lines. The spectra are organized into seven spectroscopic bins by using k-means clustering. Each cluster corresponds to, and reveals, a morphological zone within NGC 7023. The zones self-organize parallel to the well-defined PDR front that coincides with an increase in intensity of the H 2 emission lines. PAH band profiles and integrated strengths are measured, classified, and mapped. The morphological zones revealed by the k-means clustering provides deeper insight into the conditions that drive variations in band strength ratios and evolution of the PAH population that otherwise would be lost. For example, certain band-band relations are bifurcated, revealing two limiting cases; one associated with the PDR, the other with the diffuse medium. Traditionally, PAH band strength ratios are used to gain insight into the properties of the emitting PAH population, i.e., charge, size, structure, and composition. Insights inferred from this work are compared and contrasted to those from Boersma et al. (first paper in this series), where the PAH emission in NGC 7023 is decomposed exclusively using the PAH spectra and tools made available through the NASA Ames PAH IR Spectroscopic Database.

  11. Concentration, composition and sources of PAHs in the coastal sediments of the exclusive economic zone (EEZ) of Qatar, Arabian Gulf.

    Science.gov (United States)

    Soliman, Y S; Al Ansari, E M S; Wade, T L

    2014-08-30

    Surface sediments were collected from sixteen locations in order to assess levels and sources of polycyclic aromatic hydrocarbons (PAHs) in sediments of Qatar exclusive economic zone (EEZ). Samples were analyzed for 16 parent PAHs, 18 alkyl homologs and for dibenzothiophenes. Total PAHs concentration (∑PAHs) ranged from 2.6 ng g(-1) to 1025 ng g(-1). The highest PAHs concentrations were in sediments in and adjacent to harbors. Alkylated PAHs predominated most of the sampling locations reaching up to 80% in offshore locations. Parent PAHs and parent high molecular weight PAHs dominated location adjacent to industrial activities and urban areas. The origin of PAHs sources to the sediments was elucidated using ternary plot, indices, and molecular ratios of specific compounds such as (Ant/Phe+Ant), (Flt/Flt+Pyr). PAHs inputs to most coastal sites consisted of mixture of petroleum and combustion derived sources. However, inputs to the offshore sediments were mainly of petroleum origin. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Polycyclic aromatic hydrocarbons (PAHs in indoor dusts of Guizhou, southwest of China: status, sources and potential human health risk.

    Directory of Open Access Journals (Sweden)

    Qin Yang

    Full Text Available Polycyclic aromatic hydrocarbons (PAHs were analyzed for 136 indoor dust samples collected from Guizhou province, southwest of China. The ∑18PAHs concentrations ranged from 2.18 μg•g-1 to 14.20 μg•g-1 with the mean value of 6.78 μg•g-1. The highest Σ18PAHs concentration was found in dust samples from orefields, followed by city, town and village. Moreover, the mean concentration of Σ18PAHs in indoor dust was at least 10% higher than that of outdoors. The 4-6 rings PAHs, contributing more than 70% of ∑18PAHs, were the dominant species. PAHs ratios, principal component analysis with multiple linear regression (PCA-MLR and hierarchical clustering analysis (HCA were applied to evaluate the possible sources. Two major origins of PAHs in indoor dust were identified as vehicle emissions and coal combustion. The mean incremental lifetime cancer risk (ILCR due to human exposure to indoor dust PAHs in city, town, village and orefield of Guizhou province, China was 6.14×10-6, 5.00×10-6, 3.08×10-6, 6.02×10-6 for children and 5.92×10-6, 4.83×10-6, 2.97×10-6, 5.81×10-6 for adults, respectively.

  13. Polycyclic aromatic hydrocarbons (PAHs) in continental shelf sediment of China: Implications for anthropogenic influences on coastal marine environment

    International Nuclear Information System (INIS)

    Liu Liangying; Wang Jizhong; Wei Gaoling; Guan Yufeng; Zeng, Eddy Y.

    2012-01-01

    Sediments collected from the continental shelf of China, embracing Yellow Sea, inner shelf of the East China Sea (ECS), and the South China Sea (SCS), were analyzed for polycyclic aromatic hydrocarbons (PAHs). The concentrations of anthropogenic PAHs (Σ 18 PAH) were 27–224 ng/g dry weight, with an average of 82 ng/g. Sedimentary PAHs in the continental shelf off China were mainly derived from mixed residues of biomass, coal, and petroleum combustion. Fluvial transport and atmospheric deposition mainly accounted for sediment PAHs in the ECS inner shelf and Yellow Sea (and the SCS), respectively. Furthermore, statistically higher levels of Σ 18 PAH (28–224 ng/g; mean 110 ng/g) in the Yellow Sea sediment than in the SCS sediment (28–109 ng/g; mean 58 ng/g) were probably resulted from higher PAH emissions from coke industry and domestic coal combustion in North China than in South China. - Highlights: ► Coal and biomass combustion was the main origin of PAHs in coastal marine sediment of China. ► Fluvial transport was the main mode for transporting PAHs to the East China Sea inner shelf. ► Atmospheric deposition largely accounted for sediment PAHs in Yellow Sea and the South China Sea. ► Regional energy use pattern in China was responsible for the spatial distribution of PAHs in coastal marine sediment. - Sources, compositions and spatial distributions of PAHs in continental shelf sediments off China are analyzed to estimate anthropogenic influences.

  14. Decreasing polycyclic aromatic hydrocarbons emission from bitumen using alternative bitumen production process

    International Nuclear Information System (INIS)

    Rasoulzadeh, Y.; Mortazavi, S.B.; Yousefi, A.A.; Khavanin, A.

    2011-01-01

    In 1988, the National Institute for Occupational Safety and Health (NIOSH) recommended that bitumen fumes should also be considered a potential occupational carcinogen and management practices such as engineering controls should be implemented. Changing the production process of bitumen, as a source control method, was investigated in our study. For the first time, a novel alternative process was used to produce paving grade bitumen with decreased PAH emissions as well as improved bitumen performance grade (PG). Post-consumer latex and natural bitumen (NB) were used as additives to obtain 60/70 modified bitumen directly from the vacuum bottom (VB) without any need for air-blowing. The emissions were produced by a laboratory fume generation rig and were sampled and analyzed by GC-Mass and GC-FID as described in NIOSH method 5515. The PG of the resulting modified 60/70 bitumen in this study covers a wider range of climatic conditions and has higher total resistance against deformation than conventional 60/70 bitumen. The total PAH emissions from modified 60/70 bitumen (100.2619 ng/g) were decreased approximately to 50% of PAHs emitted from conventional 60/70 bitumen (197.696 ng/g). Therefore, it is possible to obtain modified bitumen with lower PAH emissions and better quality than conventional bitumen via additives and without air-blowing.

  15. Occurrence and distribution of Polycyclic aromatic hydrocarbons (PAHs) in seawater, sediments and corals from Hainan Island, China.

    Science.gov (United States)

    Xiang, Nan; Jiang, Chunxia; Yang, Tinghan; Li, Ping; Wang, Haihua; Xie, Yanli; Li, Sennan; Zhou, Hailong; Diao, Xiaoping

    2018-05-15

    The levels of 16 US EPA priority polycyclic aromatic hydrocarbons (PAHs) were investigated in corals, ambient seawater and sediments of Hainan Island, China, using gas chromatography - mass spectrometry (GC-MS). The total PAHs (∑PAHs) concentrations ranged from 273.79 to 407.82ng/L in seawater. Besides, the concentrations of ∑PAHs in corals 333.88-727.03ng/g dw) were markedly (P corals. The highest concentration of ∑PAHs was detected at site S2 in Pavona decussate, which also bore the highest ∑PAHs levels in both seawater and sediments. The massive corals were more enriched with PAHs than the branching corals. Although 2 and 3-ring PAHs were predominant and accounted for 69.27-80.46% of the ∑PAHs in corals and ambient environment, the levels of high molecular weight (HMW) PAHs (4-6 ring) in corals also demonstrated their potential dangers for corals and organisms around coral reefs. Biota-sediment accumulation factor (BSAF) refers to an index of the pollutant absorbed by aquatic organisms from the surrounding sediments. The poor correlation between log BSAF and log K ow (hydrophobicity) indicated that PAHs in corals maybe not bioaccumulate from the ambient sediments but through pathways like absorbing from seawater, symbiosis, and feeding. Based on our data, long-term ecological monitoring in typical coral reef ecosystems combined with ecotoxicological tests of PAHs on corals is necessary to determine the impacts of PAHs on coral reefs. Copyright © 2018 Elsevier Inc. All rights reserved.

  16. PAH features within few hundred parsecs of active galactic nuclei

    Science.gov (United States)

    Jensen, J. J.; Hönig, S. F.; Rakshit, S.; Alonso-Herrero, A.; Asmus, D.; Gandhi, P.; Kishimoto, M.; Smette, A.; Tristram, K. R. W.

    2017-09-01

    in the use of PAH emission as a star formation tracer within a kpc around AGN.

  17. Geographic variations in female breast cancer incidence in relation to ambient air emissions of polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Large, Courtney; Wei, Yudan

    2017-07-01

    A significant geographic variation of breast cancer incidence exists, with incidence rates being much higher in industrialized regions. The objective of the current study was to assess the role of environmental factors such as exposure to ambient air pollution, specifically carcinogenic polycyclic aromatic hydrocarbons (PAHs) that may be playing in the geographic variations in breast cancer incidence. Female breast cancer incidence and ambient air emissions of PAHs were examined in the northeastern and southeastern regions of the USA by analyzing data from the Surveillance, Epidemiology, and End Results (SEER) Program and the State Cancer Profiles of the National Cancer Institute and from the Environmental Protection Agency. Linear regression analysis was conducted to evaluate the association between PAH emissions and breast cancer incidence in unadjusted and adjusted models. Significantly higher age-adjusted incidence rates of female breast cancer were seen in northeastern SEER regions, when compared to southeastern regions, during the years of 2000-2012. After adjusting for potential confounders, emission densities of total PAHs and four carcinogenic individual PAHs (benzo[a]pyrene, dibenz[a,h]anthracene, naphthalene, and benzo[b]fluoranthene) showed a significantly positive association with annual incidence rates of breast cancer, with a β of 0.85 (p = 0.004), 58.37 (p = 0.010), 628.56 (p = 0.002), 0.44 (p = 0.041), and 77.68 (p = 0.002), respectively, among the northeastern and southeastern states. This study suggests a potential relationship between ambient air emissions of carcinogenic PAHs and geographic variations of female breast cancer incidence in the northeastern and southeastern US. Further investigations are needed to explore these interactions and elucidate the role of PAHs in regional variations of breast cancer incidence.

  18. Gas-phase polynuclear aromatic hydrocarbons (PAH) in vehicle exhaust: A method for collection and analysis

    International Nuclear Information System (INIS)

    Seigl, W.O.; Chladek, E.

    1990-01-01

    Gas-phase polynuclear aromatic hydrocarbons (PAH) are emitted at low levels in vehicle exhaust compared to other hydrocarbon emissions. A method has been developed involving the trapping of gas phase emissions on Tenax, a macrorecticular porous polymer, followed by thermal desorption onto a capillary gas chromatography column. Gas chromatography/mass spectrometry (GC/MS) was used for the chemical analysis. A detection limit of 0.05 ng was achieved for several gas-phase PAH. This high sensitivity enables the speciation and quantitation of gas-phase PAH collected from a dilution tube during standard driving (test) cycles. The method was demonstrated for the analysis of 9 PAH in the exhaust from a 1987 vehicle (with and without catalyst) during the hot start transient phase of the EPA urban dynamometer driving schedule. The PAH measured include naphthalene, 2-methyl- and 1-methylnaphthalene, biphenyl, fluorene, phenanthrene, anthracene, fluoranthene and pyrene. The four most abundant PAH observed are naphthalene, 2-methyl and 1-methylnaphthalene, and biphenyl, in that order

  19. Application of positive matrix factorization to identify potential sources of PAHs in soil of Dalian, China

    International Nuclear Information System (INIS)

    Wang Degao; Tian Fulin; Yang Meng; Liu Chenlin; Li Yifan

    2009-01-01

    Soil derived sources of polycyclic aromatic hydrocarbons (PAHs) in the region of Dalian, China were investigated using positive matrix factorization (PMF). Three factors were separated based on PMF for the statistical investigation of the datasets both in summer and winter. These factors were dominated by the pattern of single sources or groups of similar sources, showing seasonal and regional variations. The main sources of PAHs in Dalian soil in summer were the emissions from coal combustion average (46%), diesel engine (30%), and gasoline engine (24%). In winter, the main sources were the emissions from coal-fired boiler (72%), traffic average (20%), and gasoline engine (8%). These factors with strong seasonality indicated that coal combustion in winter and traffic exhaust in summer dominated the sources of PAHs in soil. These results suggested that PMF model was a proper approach to identify the sources of PAHs in soil. - PMF model is a proper approach to identify potential sources of PAHs in soil based on the PAH profiles measured in the field and those published in the literature.

  20. Evaluation of stream water quality data generated from MODIS images in modeling total suspended solid emission to a freshwater lake.

    Science.gov (United States)

    Ayana, Essayas K; Worqlul, Abeyou W; Steenhuis, Tammo S

    2015-08-01

    Modeling of suspended sediment emission into freshwater lakes is challenging due to data gaps in developing countries. Existing models simulate sediment concentration at a gauging station upstream and none of these studies had modeled total suspended solids (TSS) emissions by inflowing rivers to freshwater lakes as there are no TSS measurements at the river mouth in the upper Blue Nile basin. In this study a 10year TSS time series data generated from remotely sensed MODIS/Terra images using established empirical relationship is applied to calibrate and validate a hydrology model for Lake Tana in Upper Blue Nile Basin. The result showed that at a monthly time scale TSS at the river mouth can be replicated with Nash-Sutcliffe efficiency (NS) of 0.34 for calibration and 0.21 for validation periods. Percent bias (PBIAS) and ratio of the root-mean-square error to the standard deviation of measured data (RSR) are all within range. Given the inaccessibility and costliness to measure TSS at river mouths to a lake the results found here are considered useful for suspended sediment budget studies in water bodies of the basin. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Determination of daily intake of elements from Philippine total diet samples using inductively coupled plasma-atomic emission spectrometry

    International Nuclear Information System (INIS)

    Leon, G.C. de; Shiraishi, K.; Kawamura, H.; Igaraishi, Y.; Palattao, M.V.; Azanon, E.M.

    1990-10-01

    Total diet samples were analyzed for major elements (Na, K, Ca, Mg, P) and some minor trace elements (Fe, Zn, Mn, Al, Sr, Cu, Ba, Yt) using inductively coupled plasma-atomic emission spectrometry (ICP-AES). Samples analyzed were classified into sex and age groups. Results for some elements (Na, K, Mg, Zn, Cu, Mn) were compared with values from Bataan dietary survey calculated using the Philippine composition table. Exceot for Na, analytical results were similar to calculated values. Analytical results for Ca and Fe were also compared with the values from Food and Nutrition Research Institute. In general, values obtained in the study were lower than the FNRI values. Comparison of the analytical and calculated results with the Japanese and ICRP data showed that Philippine values were lower than foreign values. (Auth.). 22 refs., 9 tabs

  2. Determination of total fluorine in five coal reference materials by proton-induced gamma-ray emission spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Roelandts, I.; Robaye, G.; Delbrouck-Habaru, J.M.; Weber, G. [University of Liege, Sart (Belgium). Dept. of Geology, Petrology and Geochemistry

    1996-03-01

    The direct non-destructive proton-induced gamma-ray emission (PIGE) technique with a germanium detector was applied to the determination of total fluorine concentration in five coal reference materials (BCR 30, NIST 1632b, NIST 1635, SARM 20 and USGS CLB-1). Duplicate analyses were made from five randomly selected bottles of each coal. Individual data are presented and some problems (calibration, proton stopping power, effects of sample heating by the proton beam, background estimation) which were encountered during this study are discussed. Sensitivity and reproducibility of the determinations, and homogeneity of the coal samples with respect to fluorine contents by analysis of variance were investigated. The present data are also compared with the few published values for these reference samples, including other PIGE data. The use of synthetic standards and spiked samples in the present study suggested that the PIGE method was more accurate than other techniques.

  3. Vertical distributions of PAHs in the sediments of four lakes in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Fukushima, Takehiko; Watanabe, Seigo; Kamiya, Koichi [Tsukuba Univ., Ibaraki (Japan). Graduate School of Life and Environment; Ozaki, Noriatsu [Hiroshima Univ., Higashihiroshima (Japan). Graduate School of Engineering

    2012-12-15

    Purpose: The purpose of this study was to elucidate historical trends, spatial variations, and the sources of polycyclic aromatic hydrocarbons (PAHs) pollution in several Japanese lakes. Materials and methods: The vertical distributions of PAHs in the core samples of sediments taken at several points in lakes Kasumigaura, Suwa, Kizaki, and Shinji were determined using a gas chromatograph equipped with a mass selective detector and combined with chronological information and the physical/elemental properties of the sediment. Results and discussion: Seventeen related compounds (congeners) typically had concentration peaks at sediment depths corresponding to the 1960s to 1970s. In Lake Shinji and one bay of Lake Kasumigaura, there was a tendency for PAH concentrations to increase downstream; in contrast, another bay of Lake Kasumigaura showed the reverse trend. During big flood events, the fluxes of PAHs increased due to large inputs of particulate matter, although PAH concentrations were reduced. For the four study lakes and other similar lakes, PAH concentrations of surface sediments were approximately proportional to population densities in the respective watersheds, while the total input of PAHs to the lakes were correlated with their population and watershed area. The source apportionment analysis using isomer ratios for the congener profiles indicated that the principal sources of the PAHs in the lake sediments were gasoline and/or diesel engine exhausts and biomass burning. Conclusions: The observed concentration peaks showed a deterioration of the chemical quality of atmospheric conditions around 1960-1970 and a recent tendency for their amelioration. Between-lake differences suggest that the influence of human activity in the watersheds influences sediment PAH concentrations. The PAH sources were identified to be of pyrogenic origin. (orig.)

  4. VUV photo-processing of PAH cations: quantitative study on the ionization versus fragmentation processes

    Science.gov (United States)

    Zhen, Junfeng; Castillo, Sarah Rodriguez; Joblin, Christine; Mulas, Giacomo; Sabbah, Hassan; Giuliani, Alexandre; Nahon, Laurent; Martin, Serge; Champeaux, Jean-Philippe; Mayer, Paul M.

    2016-01-01

    Interstellar polycyclic aromatic hydrocarbons (PAHs) are strongly affected by the absorption of vacuum ultraviolet (VUV) photons in the interstellar medium (ISM), yet the branching ratio between ionization and fragmentation is poorly studied. This is crucial for the stability and charge state of PAHs in the ISM in different environments, affecting in turn the chemistry, the energy balance, and the contribution of PAHs to the extinction and emission curves. We studied the interaction of PAH cations with VUV photons in the 7 – 20 eV range from the synchrotron SOLEIL beamline, DESIRS. We recorded by action spectroscopy the relative intensities of photo-fragmentation and photo-ionization for a set of eight PAH cations ranging in size from 14 to 24 carbon atoms, with different structures. At photon energies below ~13.6 eV fragmentation dominates for the smaller species, while for larger species ionization is immediately competitive after the second ionization potential (IP). At higher photon energies, all species behave similarly, the ionization yield gradually increases, leveling off between 0.8 and 0.9 at ~18 eV. Among isomers, PAH structure appears to mainly affect the fragmentation cross section, but not the ionization cross section. We also measured the second IP for all species and the third IP for two of them, all are in good agreement with theoretical ones confirming that PAH cations can be further ionized in the diffuse ISM. Determining actual PAH dication abundances in the ISM will require detailed modeling. Our measured photo-ionization yields for several PAH cations provide a necessary ingredient for such models. PMID:27212712

  5. VUV photo-processing of PAH cations: quantitative study on the ionization versus fragmentation processes.

    Science.gov (United States)

    Zhen, Junfeng; Castillo, Sarah Rodriguez; Joblin, Christine; Mulas, Giacomo; Sabbah, Hassan; Giuliani, Alexandre; Nahon, Laurent; Martin, Serge; Champeaux, Jean-Philippe; Mayer, Paul M

    2016-05-10

    Interstellar polycyclic aromatic hydrocarbons (PAHs) are strongly affected by the absorption of vacuum ultraviolet (VUV) photons in the interstellar medium (ISM), yet the branching ratio between ionization and fragmentation is poorly studied. This is crucial for the stability and charge state of PAHs in the ISM in different environments, affecting in turn the chemistry, the energy balance, and the contribution of PAHs to the extinction and emission curves. We studied the interaction of PAH cations with VUV photons in the 7 - 20 eV range from the synchrotron SOLEIL beamline, DESIRS. We recorded by action spectroscopy the relative intensities of photo-fragmentation and photo-ionization for a set of eight PAH cations ranging in size from 14 to 24 carbon atoms, with different structures. At photon energies below ~13.6 eV fragmentation dominates for the smaller species, while for larger species ionization is immediately competitive after the second ionization potential (IP). At higher photon energies, all species behave similarly, the ionization yield gradually increases, leveling off between 0.8 and 0.9 at ~18 eV. Among isomers, PAH structure appears to mainly affect the fragmentation cross section, but not the ionization cross section. We also measured the second IP for all species and the third IP for two of them, all are in good agreement with theoretical ones confirming that PAH cations can be further ionized in the diffuse ISM. Determining actual PAH dication abundances in the ISM will require detailed modeling. Our measured photo-ionization yields for several PAH cations provide a necessary ingredient for such models.

  6. VUV PHOTO-PROCESSING OF PAH CATIONS: QUANTITATIVE STUDY ON THE IONIZATION VERSUS FRAGMENTATION PROCESSES

    International Nuclear Information System (INIS)

    Zhen, Junfeng; Castillo, Sarah Rodriguez; Joblin, Christine; Mulas, Giacomo; Sabbah, Hassan; Giuliani, Alexandre; Nahon, Laurent; Martin, Serge; Champeaux, Jean-Philippe; Mayer, Paul M.

    2016-01-01

    Interstellar polycyclic aromatic hydrocarbons (PAHs) are strongly affected by the absorption of vacuum ultraviolet (VUV) photons in the interstellar medium (ISM), yet the branching ratio between ionization and fragmentation is poorly studied. This is crucial for the stability and charge state of PAHs in the ISM in different environments, affecting in turn the chemistry, the energy balance, and the contribution of PAHs to the extinction and emission curves. We studied the interaction of PAH cations with VUV photons in the 7–20 eV range from the synchrotron SOLEIL beamline, DESIRS. We recorded by action spectroscopy the relative intensities of photo-fragmentation and photo-ionization for a set of eight PAH cations ranging in size from 14 to 24 carbon atoms, with different structures. At photon energies below ∼13.6 eV fragmentation dominates for the smaller species, while for larger species ionization is immediately competitive after the second ionization potential (IP). At higher photon energies all species behave similarly; the ionization yield gradually increases, leveling off between 0.8 and 0.9 at ∼18 eV. Among isomers, PAH structure appears to mainly affect the fragmentation cross section but not the ionization cross section. We also measured the second IP for all species and the third IP for two of them; all are in good agreement with theoretical ones, confirming that PAH cations can be further ionized in the diffuse ISM. Determining actual PAH dication abundances in the ISM will require detailed modeling. Our measured photo-ionization yields for several PAH cations provide a necessary ingredient for such models.

  7. VUV PHOTO-PROCESSING OF PAH CATIONS: QUANTITATIVE STUDY ON THE IONIZATION VERSUS FRAGMENTATION PROCESSES

    Energy Technology Data Exchange (ETDEWEB)

    Zhen, Junfeng; Castillo, Sarah Rodriguez; Joblin, Christine; Mulas, Giacomo; Sabbah, Hassan [Université de Toulouse, UPS-OMP, Institut de Recherche en Astrophysique et Planétologie, Toulouse (France); Giuliani, Alexandre; Nahon, Laurent [Synchrotron SOLEIL, LOrme des Merisiers, F-91192 Gif sur Yvette Cedex (France); Martin, Serge [Institut Lumière Matière, Université Lyon 1-CNRS, Université de Lyon, F-69622 Villeurbanne cedex (France); Champeaux, Jean-Philippe [Laboratoire Collisions Agrégats Réactivité, Université de Toulouse, UPS-IRSAMC, CNRS, 118 Route de Narbonne, Bat 3R1B4, F-31062 Toulouse Cedex 9 (France); Mayer, Paul M., E-mail: christine.joblin@irap.omp.eu [Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa K1N 6N5 (Canada)

    2016-05-10

    Interstellar polycyclic aromatic hydrocarbons (PAHs) are strongly affected by the absorption of vacuum ultraviolet (VUV) photons in the interstellar medium (ISM), yet the branching ratio between ionization and fragmentation is poorly studied. This is crucial for the stability and charge state of PAHs in the ISM in different environments, affecting in turn the chemistry, the energy balance, and the contribution of PAHs to the extinction and emission curves. We studied the interaction of PAH cations with VUV photons in the 7–20 eV range from the synchrotron SOLEIL beamline, DESIRS. We recorded by action spectroscopy the relative intensities of photo-fragmentation and photo-ionization for a set of eight PAH cations ranging in size from 14 to 24 carbon atoms, with different structures. At photon energies below ∼13.6 eV fragmentation dominates for the smaller species, while for larger species ionization is immediately competitive after the second ionization potential (IP). At higher photon energies all species behave similarly; the ionization yield gradually increases, leveling off between 0.8 and 0.9 at ∼18 eV. Among isomers, PAH structure appears to mainly affect the fragmentation cross section but not the ionization cross section. We also measured the second IP for all species and the third IP for two of them; all are in good agreement with theoretical ones, confirming that PAH cations can be further ionized in the diffuse ISM. Determining actual PAH dication abundances in the ISM will require detailed modeling. Our measured photo-ionization yields for several PAH cations provide a necessary ingredient for such models.

  8. Source characterisation and distribution of selected PCBs, PAHs and alkyl PAHs in sediments from the Klip and Jukskei Rivers, South Africa.

    Science.gov (United States)

    Rimayi, Cornelius; Chimuka, Luke; Odusanya, David; de Boer, Jacob; Weiss, Jana M

    2017-07-01

    A study of the distribution of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) utilising 16 priority PAHs, benzo(e)pyrene, perylene, 19 alkylated PAHs and 31 ortho substituted PCBs in South Africa is presented. It was aimed to (a) deduce characteristic contamination patterns for both PCBs and PAHs and (b) provide the first comprehensive dataset for establishment of source characterisation of PCBs and PAHs. This is in line with new South African legislation on mandatory monitoring of PCB and PAH emissions. Bar charts, principal component analysis (PCA) and biplots were utilised to identify signature contamination patterns and distribution of PCBs and PAHs within the Jukskei and Klip Rivers. Sediments from the Jukskei and Klip River catchments both showed distinct contamination signatures for hexa to nonachlorinated PCBs, characteristic of contamination by Aroclor 1254 and 1260 technical mixtures. PCB signature patterns in order of abundance were 138 > 180 > 206 > 153 > 187 > 149 and 138 > 153 > 180 > 149 > 187 > 110 > 170 for the Jukskei and Klip River sediments, respectively. The upstream Alberton point had the highest Σ31 PCB and Σ (parent+alkyl) PAH concentrations in the Klip River of 61 and 6000 μg kg -1 dry weight (dw), respectively. In the Jukskei River, the upstream Marlboro point had the highest Σ31 PCB concentration of 19 μg kg -1 dw and the N14 site recorded the highest Σ (parent+alkyl) PAH concentration of 2750 μg kg -1 dw. PAH concentrations in both the Jukskei and Klip Rivers were significantly higher than the PCB concentrations. Fluoranthene, phenanthrene and pyrene were found in the highest concentrations in both the Jukskei and Klip River sediments. Both the Jukskei and Klip River sediments showed trends of a mixed pyrogenic-petrogenic PAH source contamination.

  9. PAHs and the Diffuse Interstellar Bands. What have we Learned from the New Generation of Laboratory and Observational Studies?

    Science.gov (United States)

    Salama, Farid

    2005-01-01

    Polycyclic Aromatic Hydrocarbons (PAHs) are an important and ubiquitous component of carbon-bearing materials in space. PAHs are the best-known candidates to account for the IR emission bands (UIR bands) and PAH spectral features are now being used as new probes of the ISM. PAHs are also thought to be among the carriers of the diffuse interstellar absorption bands (DIBs). In the model dealing with the interstellar spectral features, PAHs are present as a mixture of radicals, ions and neutral species. PAH ionization states reflect the ionization balance of the medium while PAH size, composition, and structure reflect the energetic and chemical history of the medium. A major challenge for laboratory astrophysics is to reproduce (in a realistic way) the physical conditions that exist in the emission and/or absorption interstellar zones, An extensive laboratory program has been developed at NASA Ames to characterize the physical and chemical properties of PAHs in astrophysical environments and to describe how they influence the radiation and energy balance in space and the interstellar chemistry. In particular, laboratory experiments provide measurements of the spectral characteristics of interstellar PAH analogs from the ultraviolet and visible range to the infrared range for comparison with astronomical data. This paper will focus on the recent progress made in the laboratory to measure the direct absorption spectra of neutral and ionized PAHs in the gas phase in the near-W and visible range in astrophysically relevant environments. These measurements provide data on PAHs and nanometer-sized particles that can now be directly compared to astronomical observations. The harsh physical conditions of the IS medium - characterized by a low temperature, an absence of collisions and strong V W radiation fields - are simulated in the laboratory by associating a molecular beam with an ionizing discharge to generate a cold plasma expansion. PAH ions are formed from the neutral

  10. Polycyclic aromatic hydrocarbons and PAH-related DNA adducts.

    Science.gov (United States)

    Ewa, Błaszczyk; Danuta, Mielżyńska-Švach

    2017-08-01

    Investigations on the impact of chemicals on the environment and human health have led to the development of an exposome concept. The exposome refers to the totality of exposures received by a person during life, including exposures to life-style factors, from the prenatal period to death. The exposure to genotoxic chemicals and their reactive metabolites can induce chemical modifications of DNA, such as, for example, DNA adducts, which have been extensively studied and which play a key role in chemically induced carcinogenesis. Development of different methods for the identification of DNA adducts has led to adopting DNA adductomic approaches. The ability to simultaneously detect multiple PAH-derived DNA adducts may allow for the improved assessment of exposure, and offer a mechanistic insight into the carcinogenic process following exposure to PAH mixtures. The major advantage of measuring chemical-specific DNA adducts is the assessment of a biologically effective dose. This review provides information about the occurrence of the polycyclic aromatic hydrocarbons (PAHs) and their influence on human exposure and biological effects, including PAH-derived DNA adduct formation and repair processes. Selected methods used for determination of DNA adducts have been presented.

  11. Distribution of particle-phase hydrocarbons, PAHs and OCPs in Tianjin, China

    Science.gov (United States)

    Wu, Shui-Ping; Tao, Shu; Zhang, Zhi-Huan; Lan, Tian; Zuo, Qian

    Aliphatic hydrocarbons, polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) were determined in the total suspended particles (TSP) collected from 13 different locations in Tianjin, China, where intensive coal burning for domestic heating in winter takes place and a large quantity of pesticides had been produced and applied. Carbon preference index (CPI), carbon number maximum (C max) of n-alkane and plant wax index (%wax C n) indicate that n-alkanes come from both biogenic and petrogenic sources, and biogenic source contributes more n-alkanes in autumn than in winter. Petroleum biomarkers as indicators of petrogenic source such as hopanes and steranes were also detected in both seasons' samples. The sum of 16 PAH concentrations (∑PAH) ranged from 69.3 to 2170 ng m -3 in winter and from 7.01 to 40.0 ng m -3 in autumn. Seasonal variations were mainly attributed to the difference in coal combustion emission and meteorological conditions. The results of a source diagnostic analysis suggest that PAHs in TSP mainly come from coal combustion. Seven OCPs (four hexachlorohexanes (HCHs) and three dichlorodipheny-trichloroethane and metabolites (DDTs)) were detected in most samples. Concentrations of the sum of α-, β-, δ- and γ-HCH (∑HCH) and the sum of p, p'-DDT, p, p'-DDD and p, p'-DDE (∑DDT) in autumn varied in the ranges of 0.002-0.9 ng m -3 and 0.025-2.21 ng m -3 with the average±standard deviation values of 0.127±0.241 ng m -3 and 0.239±0.546 ng m -3, respectively. In winter, ∑HCH and ∑DDT in TSP ranged from 0.071 to 5.35 ng m -3 and from 0.416 to 3.14 ng m -3 with the average±standard deviation values 1.05±1.88 ng m -3 and 0.839±0.713 ng m -3, respectively. Both of the illegal application of technical HCH and DDT and the volatilization from topsoil contributed to the particle-phase contents of HCHs and DDTs in the atmosphere.

  12. Light vehicle regulated and unregulated emissions from different biodiesels

    International Nuclear Information System (INIS)

    Karavalakis, George; Stournas, Stamoulis; Bakeas, Evangelos

    2009-01-01

    In this study, the regulated and unregulated emissions profile and fuel consumption of an automotive diesel and biodiesel blends, prepared from two different biodiesels, were investigated. The biodiesels were a rapeseed methyl ester (RME) and a palm-based methyl ester (PME). The tests were performed on a chassis dynamometer with constant volume sampling (CVS) over the New European Driving Cycle (NEDC) and the non-legislated Athens Driving Cycle (ADC), using a Euro 2 compliant passenger vehicle. The objectives were to evaluate the impact of biodiesel chemical structure on the emissions, as well as the influence of the applied driving cycle on the formation of exhaust emissions and fuel consumption. The results showed that NOx emissions were influenced by certain biodiesel properties, such as those of cetane number and iodine number. NOx emissions followed a decreasing trend over both cycles, where the most beneficial reduction was obtained with the application of the more saturated biodiesel. PM emissions were decreased with the palm-based biodiesel blends over both cycles, with the exception of the 20% blend which was higher compared to diesel fuel. PME blends led to increases in PM emissions over the ADC. The majority of the biodiesel blends showed a tendency for lower CO and HC emissions. The differences in CO2 emissions were not statistically significant. Fuel consumption presented an increase with both biodiesels. Total PAH and nitro-PAH emission levels were decreased with the use of biodiesel independently of the source material. Lower molecular weight PAHs were predominant in both gaseous and particulate phases. Both biodiesels had a negative impact on certain carbonyl emissions. Formaldehyde and acetaldehyde were the dominant aldehydes emitted from both fuels.

  13. Sediment-porewater partition of polycyclic aromatic hydrocarbons (PAHs) from Lanzhou Reach of Yellow River, China

    Energy Technology Data Exchange (ETDEWEB)

    Yu Yong [Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, College of Environmental Science and Engineering, Nankai University, Tianjin 300071 (China); Xu Jian, E-mail: xujian@nankai.edu.cn [Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, College of Environmental Science and Engineering, Nankai University, Tianjin 300071 (China); Wang Ping; Sun Hongwen; Dai Shugui [Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, College of Environmental Science and Engineering, Nankai University, Tianjin 300071 (China)

    2009-06-15

    Pollution of polycyclic aromatic hydrocarbons (PAHs) in the aquatic environment has drawn much attention around the world. The occurrence of 16 priority PAHs in the sediments and corresponding porewaters in Lanzhou Reach of Yellow River, China, and their partitioning behavior between the two phases were investigated. The results demonstrated that the total PAH levels in the sediments were positively correlated with the sediment clay contents (R{sup 2} = 0.756). Concentrations of total PAHs in porewaters ranged from 48.2 to 206 {mu}g/L, and indeno[1,2,3-cd]pyrene (InP) was the most abundant compound measured in the porewater samples with a mean value of 42.9 {mu}g/L. The compositions of PAHs in porewaters were dominated by their compositions in the sediment samples. The in situ organic carbon normalized partition coefficients (logK{sub oc}{sup '}) of the PAHs between sediments and porewaters were significantly correlated with their octanol-water partition coefficients (log K{sub ow}) when log K{sub ow} values were less than 5.5 (naphthalene (Nap) excluded). logK{sub oc}{sup '} values of 14 PAHs were lower than those predicted by the Karickhoff relationship. This discrepancy was largest for InP, dibenzo[a,h]anthracene (DBA), and benzo[ghi]perylene (BgP). The results in present study showed the tendency of PAHs release from sediment to porewater, indicating that PAHs sequestered in the sediments may be a pollution source to aquatic ecosystem.

  14. PAHS

    African Journals Online (AJOL)

    user

    2011-03-02

    Mar 2, 2011 ... spillage's and/or heavy ship traffic. However, the ... various aspects such as industrial effluents, air, highway vehicle exhaust and highway .... detection (LOD) of the GC-MS method, established at signals three times that of the.

  15. Genetic study of the PAH locus in the Iranian population: familial gene mutations and minihaplotypes.

    Science.gov (United States)

    Razipour, Masoumeh; Alavinejad, Elaheh; Sajedi, Seyede Zahra; Talebi, Saeed; Entezam, Mona; Mohajer, Neda; Kazemi-Sefat, Golnaz-Ensieh; Gharesouran, Jalal; Setoodeh, Aria; Mohaddes Ardebili, Seyyed Mojtaba; Keramatipour, Mohammad

    2017-10-01

    Phenylketonuria (PKU), one of the most common inborn errors of amino acid metabolism, is caused by mutations in the phenylalanine hydroxylase (PAH) gene (PAH). PKU has wide allelic heterogeneity, and over 600 different disease-causing mutations in PAH have been detected to date. Up to now, there have been no reports on the minihaplotype (VNTR/STR) analysis of PAH locus in the Iranian population. The aims of the present study were to determine PAH mutations and minihaplotypes in Iranian families with PAH deficiency and to investigate the correlation between them. A total of 81 Iranian families with PAH deficiency were examined using PCR-sequencing of all 13 PAH exons and their flanking intron regions to identify sequence variations. Fragment analysis of the PAH minihaplotypes was performed by capillary electrophoresis for 59 families. In our study, 33 different mutations were found accounting for 95% of the total mutant alleles. The majority of these mutations (72%) were distributed across exons 7, 11, 2 and their flanking intronic regions. Mutation c.1066-11G > A was the most common with a frequency of 20.37%. The less frequent mutations, p.Arg261Gln (8%), p.Arg243Ter (7.4%), p.Leu48Ser (7.4%), p.Lys363Asnfs*37 (6.79%), c.969 + 5G > A (6.17%), p.Pro281Leu (5.56), c.168 + 5G > C (5.56), and p.Arg261Ter (4.94) together comprised about 52% of all mutant alleles. In this study, a total of seventeen PAH gene minihaplotypes were detected, six of which associated exclusively with particular mutations. Our findings indicate a broad PAH mutation spectrum in the Iranian population, which is consistent with previous studies reporting a wide range of PAH mutations, most likely due to ethnic heterogeneity. High prevalence of c.1066-11G > A mutation linked to minihaplotype 7/250 among both Iranian and Mediterranean populations is indicative of historical and geographical links between them. Also, strong association between particular mutations and minihaplotypes

  16. Extension of EU Emissions Trading Scheme to Other Sectors and Gases: Consequences for Uncertainty of Total Tradable Amount

    International Nuclear Information System (INIS)

    Monni, S.; Syri, S.; Pipatti, R.; Savolainen, I.

    2007-01-01

    Emissions trading in the European Union (EU), covering the least uncertain emission sources of greenhouse gas emission inventories (CO 2 from combustion and selected industrial processes in large installations), began in 2005. During the first commitment period of the Kyoto Protocol (2008-2012), the emissions trading between Parties to the Protocol will cover all greenhouse gases (CO 2 , CH 4 , N 2 O, HFCs, PFCs, and SF 6 ) and sectors (energy, industry, agriculture, waste, and selected land-use activities) included in the Protocol. In this paper, we estimate the uncertainties in different emissions trading schemes based on uncertainties in corresponding inventories. According to the results, uncertainty in emissions from the EU15 and the EU25 included in the first phase of the EU emissions trading scheme (2005-2007) is ±3% (at 95% confidence interval relative to the mean value). If the trading were extended to CH 4 and N 2 O, in addition to CO 2 , but no new emissions sectors were included, the tradable amount of emissions would increase by only 2% and the uncertainty in the emissions would range from -4 to +8%. Finally, uncertainty in emissions included in emissions trading under the Kyoto Protocol was estimated to vary from -6 to +21%. Inclusion of removals from forest-related activities under the Kyoto Protocol did not notably affect uncertainty, as the volume of these removals is estimated to be small

  17. Integrated technology selection for energy conservation and PAHs control in iron and steel industry: Methodology and case study

    International Nuclear Information System (INIS)

    Li, Li; Lu, Yonglong; Shi, Yajuan; Wang, Tieyu; Luo, Wei; Gosens, Jorrit; Chen, Peng; Li, Haiqian

    2013-01-01

    Energy conservation and PAHs (polycyclic aromatic hydrocarbon) control are two challenges for the iron and steel industry, especially where the industry has developed at high speed. How to select appropriate technologies to improve energy efficiency and control pollution from PAHs simultaneously is encountered by both the researchers and the decision makers. This study sets up a framework on technology selection and combination which integrates technology assessment, multiple objective programming and scenario analysis. It can predict proper technology combination for different emission controls, energy conservation targets and desired levels of production. An iron and steel factory in Southwestern China is cited as a case. It is shown that stricter PAHs control will drive the transformation from process control technology to alternative smelting technology. In low PAHs limit, 25% energy reduction is a threshold. Before inclusion of a restraint on energy consumption at 25% reduction, PAHs emission is the key limiting factor for the technology selection; while after inclusion of this restraint, energy consumption becomes the key limiting factor. The desired level of production will also influence the technology selection. This study can help decision makers to select appropriate technologies to meet the PAHs control objectives and energy conservation strategies in energy-intensive industries. - Highlights: ► We predict technical strategy for energy and PAHs reduction in iron and steel mill. ► With low PAHs control objectives, process control technologies are preferable. ► With medium and high PAHs control goals, alternative smelting technology is dominate. ► In low PAHs control objective, 25% energy reduction is a threshold

  18. Dietary risk evaluation for 28 polycyclic aromatic hydrocarbons (PAHs) in tea preparations made of teas available on the Polish retail market.

    Science.gov (United States)

    Roszko, Marek; Kamińska, Marta; Szymczyk, Krystyna; Jędrzejczak, Renata

    2018-01-02

    The aim of this work was to assess dietary risk resulting from consumption of polycyclic aromatic hydrocarbons (PAHs) with tea infusions. To this end, levels of 28 PAHs in black, green, red and white teas available on the Polish retail market have been assessed. Profiles and correlation between concentrations of individual PAHs have been identified. A model study on transfer of PAHs from tea leaves into tea preparations has been conducted. Relatively high concentrations of 28 evaluated PAHs have been found in 58 tested samples of black, green, red and white teas sampled on the Polish retail market. Total concentration ∑28PAH ranged from 57 to 696 µg kg -1 with mean 258 µg kg -1 (dry tea leaves). The most mature tea leaves fermented to a small degree contained relatively the highest PAH levels among all four tested tea types. Relatively low PAH transfer rates into tea infusions and limited volumes of the consumed tea keep the risks associated with PAH dietary intake at a safely low level. The worst-case scenario dietary intake values were 7.62/0.82/0.097 ng kg -1 b.w. day -1 (estimated on the basis of the maximum found concentrations 696/113/23 µg kg -1 and maximum observed transfer rates 24/16/9%) for ∑28PAH/∑PAH4/B[a]P, respectively. MOE values calculated using the above worst case estimates exceeded 700,000 and 400,000 (BMDL 10 0.07 and 0.34 mg kg -1 b.w. day -1 ) for B[a]P and PAH4, respectively. Both B[a]P and PAH4 concentrations may be used as indicators of total PAH concentration in tea leaves; PAH4 slightly better fits low molecular weight PAHs. Several correlations between various PAHs/groups of PAHs have been identified, the strongest one (R 2 = 0.92) between PAH4 and EU PAH 15+1.

  19. Exposure Assessment of Polycyclic Aromatic Hydrocarbon (PAHs) in Childcare Centers of Muang, Nakhon Ratchasima

    Science.gov (United States)

    Jitlada, C.; Pentamwa, P.

    2018-03-01

    This study aims to characterize airborne polycyclic aromatic hydrocarbons (PAHs) as of particulate and vapor phases variation. The samples were collected from the childcare centers where divided into urban and rural areas in Nakhon Ratchasima Province of Thailand. The airborne samples were collected from five childcare centers during the dry season in the year 2017. The PAHs species were determined by the gas chromatography and mass spectroscopy (GS/MS) method. Results show that the total concentrations of PAHs were higher than vapor phase that both similar in urban area and rural area. The dominant PAHs compounds of both urban and rural areas were benzo(a)pyrene, benzo(a,h)anthracene and indeno(1,2,3-cd)pyrene, respectively. Furthermore, the concentrations of PAHs in municipality (urban) childcare centers were higher than rural childcare centers area of Nakhon Ratchasima province. The risks associated with exposure to PAHs were evaluated using the TEF approach. The estimated value of lifetime lung cancer risks children in urban were significantly (p < 0.05) 2 times of children in rural, thus demonstrating that exposure to PAHs at levels found at urban site may be cause potential health risks.

  20. Bimonthly assessment of PAH content in wild mussels from the Spanish Atlantic Coast

    Directory of Open Access Journals (Sweden)

    Juan Antonio Campillo

    2014-06-01

    Full Text Available During 2013-14 wild mussels were bimonthly sampled in five stations along the Spanish Atlantic coast in order to assess any temporal variation in the concentration of parent PAHs. The sampling stations selected (Oia, Raxó, Mera, Avilés and Pedreña included both polluted and unpolluted sites and tried to reflect the different situations in the area (coastal and more estuarine waters. The samples were shipped to the lab and three homogenates from each site were prepared and frozen until analysis. 13 parent PAHs were quantified using HPLC with fluorescence detection. In general, the highest concentrations were found in the January-March sampling, during the pre-spawning period. PAHs contents were related to mussel biochemical composition, mainly carbohydrates and lipids, and to mussel reproductive stage. In general the 4-ring PAHs is the most abundant group of PAHs. The input of the HMW PAHs (4-5 rings to the total PAH burden generally increases in the winter months probably due to both different sources in that season (building heatings and the remobilization of sediments.

  1. Chemical-assisted phytoremediation of CD-PAHs contaminated soils using Solanum nigrum L.

    Science.gov (United States)

    Yang, Chuanjie; Zhou, Qixing; Wei, Shuhe; Hu, Yahu; Bao, Yanyu

    2011-09-01

    A well-characterized cadmium (Cd) hyperaccumulating plant Solanum nigrum was grown in Cd and polycyclic aromatic hydrocarbons (PAHs) co-contaminated soil that was repeatedly amended with chemicals, including EDTA, cysteine (CY), salicylic acid (Sa), and Tween 80 (TW80), to test individual and combined treatment effects on phytoremediation of Cd-PAHs contaminated soils. Plant growth was negatively affected by exogenous chemicals except for EDTA. S. nigrum could accumulate Cd in tissues without assistant chemicals, while there was no visible effect on the degradation of PAHs. Cysteine had significant effects on phytoextraction of Cd and the highest metal extraction ratio (1.27%) was observed in 0.9 mmol/kg CY treatment. Both salicylic acid and Tween 80 had stimulative effects on the degradation of PAHs and there was the maximal degradation rate (52.6%) of total PAHs while 0.9 mmol/kg Sa was applied. Furthermore, the combined treatment T(0.1EDTA+0.9CY+0.5TW80) and T(0.5EDTA+0.9CY+03Sa) could not only increase the accumulation of Cd in plant tissues, but also promote the degradation of PAHs. These results indicated that S. nigrum might be effective in phytoextracting Cd and enhancing the biodegradation of PAHs in the co-contaminated soils with assistant chemicals.

  2. Regional modelling of polycyclic aromatic hydrocarbons: WRF-Chem-PAH model development and East Asia case studies

    Science.gov (United States)

    Mu, Qing; Lammel, Gerhard; Gencarelli, Christian N.; Hedgecock, Ian M.; Chen, Ying; Přibylová, Petra; Teich, Monique; Zhang, Yuxuan; Zheng, Guangjie; van Pinxteren, Dominik; Zhang, Qiang; Herrmann, Hartmut; Shiraiwa, Manabu; Spichtinger, Peter; Su, Hang; Pöschl, Ulrich; Cheng, Yafang

    2017-10-01

    Polycyclic aromatic hydrocarbons (PAHs) are hazardous pollutants, with increasing emissions in pace with economic development in East Asia, but their distribution and fate in the atmosphere are not yet well understood. We extended the regional atmospheric chemistry model WRF-Chem (Weather Research Forecast model with Chemistry module) to comprehensively study the atmospheric distribution and the fate of low-concentration, slowly degrading semivolatile compounds. The WRF-Chem-PAH model reflects the state-of-the-art understanding of current PAHs studies with several new or updated features. It was applied for PAHs covering a wide range of volatility and hydrophobicity, i.e. phenanthrene, chrysene and benzo[a]pyrene, in East Asia. Temporally highly resolved PAH concentrations and particulate mass fractions were evaluated against observations. The WRF-Chem-PAH model is able to reasonably well simulate the concentration levels and particulate mass fractions of PAHs near the sources and at a remote outflow region of East Asia, in high spatial and temporal resolutions. Sensitivity study shows that the heterogeneous reaction with ozone and the homogeneous reaction with the nitrate radical significantly influence the fate and distributions of PAHs. The methods to implement new species and to correct the transport problems can be applied to other newly implemented species in WRF-Chem.

  3. Concentrations of PAHs (Polycyclicaromatic Hydrocarbons Pollutant in Sediment of The Banten Bay

    Directory of Open Access Journals (Sweden)

    Khozanah Munawir

    2018-02-01

    Full Text Available Banten Bay is end of stream for a few rivers from Banten mainland where many manufactures and petrochemical industries are built. This may give environmental pressure of water quality of the bay due to pollutant input, such as Polycyclic Aromatic Hydrocarbons (PAHs. This study is to identify those pollutants and determine their total concentration and distribution in sediments. Surface sediment samples were collected in four zones: inner coastline within the bay, middle bay, coastline off the bay and outer of the Bay in April 2016. PAH components were extracted and measured using a gas chromatography-mass spectrometry. Levels of total PAHs in sediments in inner coastline within the bay ranged between 0.381-2.654 ppm with an average of 1.288 ppm, middle of the bay ranged between 0.747-1.762 ppm with an average of 1.198 ppm, outer of the bay ranged between 0.192-1.394 ppm with an average of 0.921 ppm, and east coast of the bay ranged between 0.191-1.394 ppm and an average of 0.778 ppm. The levels of total PAH contamination is apparently lower than those of PAH threshold in sediments (i.e. 4.5 ppm. Keywords: PAHs (Polycyclic Aromatic Hydrocarbons, Banten Bay

  4. Response of bacterial pdo1, nah, and C12O genes to aged soil PAH pollution in a coke factory area.

    Science.gov (United States)

    Han, Xue-Mei; Liu, Yu-Rong; Zheng, Yuan-Ming; Zhang, Xiao-Xia; He, Ji-Zheng

    2014-01-01

    Soil pollution caused by polycyclic aromatic hydrocarbons (PAHs) is threatening human health and environmental safety. Investigating the relative prevalence of different PAH-degrading genes in PAH-polluted soils and searching for potential bioindicators reflecting the impact of PAH pollution on microbial communities are useful for microbial monitoring, risk evaluation, and potential bioremediation of soils polluted by PAHs. In this study, three functional genes, pdo1, nah, and C12O, which might be involved in the degradation of PAHs from a coke factory, were investigated by real-time quantitative PCR (qPCR) and clone library approaches. The results showed that the pdo1 and C12O genes were more abundant than the nah gene in the soils. There was a significantly positive relationship between the nah or pdo1 gene abundances and PAH content, while there was no correlation between C12O gene abundance and PAH content. Analyses of clone libraries showed that all the pdo1 sequences were grouped into Mycobacterium, while all the nah sequences were classified into three groups: Pseudomonas, Comamonas, and Polaromonas. These results indicated that the abundances of nah and pdo1 genes were positively influenced by levels of PAHs in soil and could be potential microbial indicators reflecting the impact of soil PAH pollution and that Mycobacteria were one of the most prevalent PAHs degraders in these PAH-polluted soils. Principal component analysis (PCA) and correlation analyses between microbial parameters and environmental factors revealed that total carbon (TC), total nitrogen (TN), and dissolved organic carbon (DOC) had positive effects on the abundances of all PAH-degrading genes. It suggests that increasing TC, TN, and DOC inputs could be a useful way to remediate PAH-polluted soils.

  5. Have Market-oriented Reforms Decoupled China’s CO2 Emissions from Total Electricity Generation? An Empirical Analysis

    Directory of Open Access Journals (Sweden)

    Wei Shang

    2016-05-01

    Full Text Available Achieving the decoupling of electric CO2 emissions from total electricity generation is important in ensuring the sustainable socioeconomic development of China. To realize this, China implemented market-oriented reforms to its electric power industry at the beginning of 2003. This study used the Tapio decoupling index, the Laspeyres decomposition algorithm, and decoupling-related data from 1993 to 2012 to evaluate the effect of these reforms. Several conclusions can be drawn based on the empirical analysis. (1 The reforms changed the developmental trend of the decoupling index and facilitated its progress towards strong decoupling. (2 The results forecasted through fitting the curve to the decoupling index indicate that strong decoupling would be realized by 2030. (3 Limiting the manufacturing development and upgrading the generation equipment of the thermal power plants are essential for China to achieve strong decoupling at an early date. (4 China should enhance regulatory pressures and guidance for appropriate investment in thermal power plants to ensure the stable development of the decoupling index. (5 Transactions between multiple participants and electricity price bidding play active roles in the stable development of the decoupling index.

  6. Interactions between selected PAHs and the microbial community in rhizosphere of a paddy soil.

    Science.gov (United States)

    Su, Yu H; Yang, Xue Y

    2009-01-15

    This study investigated the interaction of three polycyclic aromatic hydrocarbons (PAHs), i.e., naphthalene (NAP), phenanthrene (PHN), and pyrene (PYR), with the microbial community in the rhizosphere of a paddy soil and the influence of the rice (Oryza sativa) rhizosphere on the microbial community structure. A range of initial NAP, PHN and PYR levels in soil (50-200, 18-72, and 6.6-26.6 mg kg(-1), respectively) were prepared and the soil samples were then aged for 4 months (to yield PAH concentrations at 1.02-1.42, 1.32-4.77, and 2.98-18.5 mg kg(-)(1), respectively) before the soil samples were planted with rice seedlings. The microbial phospholipid-fatty-acid (PLFA) patterns in PAH-contaminated soils were analyzed to elucidate the changes of the microbial biomass and community composition. Results indicated that at the applied concentrations the PAHs were not toxic to rice seedlings, as evidenced by no growth inhibition during the 8-week planting period. However, the microbial biomass, as revealed by PLFAs, decreased significantly with increasing PAH concentration in both rhizospheric and non-rhizospheric soils. The PAHs in soils were obviously toxic to microorganisms, and the toxicity of PHN was greater than PYR due likely to the higher PHN bioavailability. Total PLFAs in rhizospheric soils were profoundly higher than those in non-rhizospheric soils, suggesting that the inhibitive effect of PAHs on microbial activities was alleviated by the rice roots. The principal component analysis (PCA) of the PLFA signatures revealed pronounced changes in PLFA pattern in rhizospheric and non-rhizospheric soils with or without spiked PAHs. Using the PLFA patterns as a biomarker, it was found that Gram-positive bacteria were more sensitive to PAHs than Gram-negative bacteria, and the rhizosphere of rice roots stimulated the growth of aerobic bacteria.

  7. Biomonitoring airborne parent and alkylated three-ring PAHs in the Greater Cologne Conurbation II: Regional distribution patterns

    International Nuclear Information System (INIS)

    Lehndorff, E.; Schwark, L.

    2009-01-01

    The spatial distribution of an important air pollutant class, three-ring polycyclic aromatic hydrocarbons and their derivatives (PAH-3), has been monitored for the Greater Cologne Conurbation (GCC) using pine needle as passive samplers. The GCC comprises one of the most heavily populated, trafficked, and industrialized regions in Germany. Here, 71 locations covering 3600 km 2 were sampled and, for the first time, isopleths maps constructed to investigate the regional variability in PAH-3 concentration and composition. The highest PAH-3 loads on needles (1000-1500 ng g -1 ) were detected downwind of three lignite fuelled power plants, followed by Cologne City (600-700 ng g -1 ) and smaller towns (400-600 ng g -1 ), whereas rural and forest regions yielded PAH-3 loads of 60-300 ng g -1 . PAH-3 ratios facilitated source reconciliation, with high dibenzothiophene versus retene values indicating lignite combustion and high 9/(9 + 1)-methylphenanthrene ratios depicting traffic emissions in inner cities. PAH-3 ratios depended on topography and outlined the heavily industrialized Rhine Valley, demonstrating atmospheric dispersal of PAH-3. - Regional high-resolution biomonitoring identified lignite combustion in power plants to dominate over urban traffic and other emission sources.

  8. Concentration and photochemistry of PAHs, NPAHs, and OPAHs and toxicity of PM2.5 during the Beijing Olympic Games.

    Science.gov (United States)

    Wang, Wentao; Jariyasopit, Narumol; Schrlau, Jill; Jia, Yuling; Tao, Shu; Yu, Tian-Wei; Dashwood, Roderick H; Zhang, Wei; Wang, Xuejun; Simonich, Staci L Massey

    2011-08-15

    Atmospheric particulate matter with diameter cells were also measured. Significant reductions in BC (45%), OC (31%), MW< 300 PAH (26-73%), MW 302 PAH (22-77%), NPAH (15-68%), and OPAH (25-53%) concentrations were measured during the source control and Olympic periods. However, the mutagenicity of the PM(2.5) was significantly reduced only during the Olympic period. The PAH, NPAH, and OPAH composition of the PM(2.5) was similar throughout the study, suggesting similar sources during the different periods. During the source control period, the parent PAH concentrations were correlated with NO, CO, and SO(2) concentrations, indicating that these PAHs were associated with both local and regional emissions. However, the NPAH and OPAH concentrations were only correlated with the NO concentrations, indicating that the NPAH and OPAH were primarily associated with local emissions. The relatively high 2-nitrofluoranthene/1-nitropyrene ratio (25-46) and 2-nitrofluoranthene/2-nitropyrene ratio (3.4-4.8), suggested a predominance of photochemical formation of NPAHs through OH-radical-initiated reactions in the atmosphere. On average, the ∑NPAH and ∑OPAH concentrations were 8% of the parent PAH concentrations, while the direct-acting mutagenicity (due to the NPAH and OPAH) was 200% higher than the indirect-acting mutagenicity (due to the PAH). This suggests that NPAH and OPAH make up a significant portion of the overall mutagenicity of PM(2.5) in Beijing.

  9. Generation and distribution of PAHs in the process of medical waste incineration.

    Science.gov (United States)

    Chen, Ying; Zhao, Rongzhi; Xue, Jun; Li, Jinhui

    2013-05-01

    After the deadly earthquake on May 12, 2008 in Wenchuan county of China, several different incineration approaches were used for medical waste disposal. This paper investigates the generation properties of polycyclic aromatic hydrocarbons (PAHs) during the incineration. Samples were collected from the bottom ash in an open burning slash site, surface soil at the open burning site, bottom ash from a simple incinerator, bottom ash generated from the municipal solid waste (MSW) incinerator used for medical waste disposal, and bottom ash and fly ash from an incinerator exclusively used for medical waste. The species of PAHs were analyzed, and the toxicity equivalency quantities (TEQs) of samples calculated. Analysis results indicate that the content of total PAHs in fly ash was 1.8×10(3) times higher than that in bottom ash, and that the strongly carcinogenic PAHs with four or more rings accumulated sensitively in fly ash. The test results of samples gathered from open burning site demonstrate that Acenaphthylene (ACY), Acenaphthene (ACE), Fluorene (FLU), Phenanthrene (PHE), Anthracene (ANT) and other PAHs were inclined to migrate into surrounding environment along air and surface watershed corridors, while 4- to 6-ring PAHs accumulated more likely in soil. Being consistent with other studies, it has also been confirmed that increases in both free oxygen molecules and combustion temperatures could promote the decomposition of polycyclic PAHs. In addition, without the influence of combustion conditions, there is a positive correlation between total PCDD/Fs and total PAHs, although no such relationship has been found for TEQ. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. PAH contamination in soils adjacent to a coal-transporting facility in Tapin district, south Kalimantan, Indonesia.

    Science.gov (United States)

    Mizwar, Andy; Trihadiningrum, Yulinah

    2015-07-01

    This study was undertaken to determine the level of 16 polycyclic aromatic hydrocarbon (PAH), listed as priority pollutants by the United States Environmental Protection Agency (USEPA), in surface soils around a coal-transporting facility in the western part of South Kalimantan, Indonesia. Three composite soil samples were collected from a coal stockpile, coal-hauling road, and coal port. Identification and quantification of PAH was performed by gas chromatography-mass spectrometry. The total content of 16 USEPA-PAH ranged from 11.79 to 55.30 mg/kg with arithmetic mean value of 33.14 mg/kg and median of 32.33 mg/kg. The 16 USEPA-PAH measured levels were found to be greater compared with most of the literature values. The levels of high molecular-weight PAH (5- and 6-ring) were dominant and formed 67.77-80.69 % of the total 16 USEPA-PAH The most abundant of individual PAH are indeno[1,2,3-cd] pyrene and benzo[a]pyrene with concentration ranges of 2.11-20.56 and 1.59-17.84 mg/kg, respectively. The degree of PAH contamination and subsequent toxicity assessment suggest that the soils of the study area are highly contaminated and pose a potential health risk to humans.

  11. Destruction of PAHs by X-Rays in circumnuclear regions of AGNs

    Science.gov (United States)

    Monfredini, T.; Wolff, W.; Boechat-Roberty, H. M.; Sales, D. A.; Pastoriza, M. G.

    2017-07-01

    Emission bands associated with PAH molecules are observed in the direction of some classes of AGNs like Seyfert 2, LINERs and obscured quasars (e.g. Kaneda et al., 2008, Sansigre et al., 2008 and Sales et al. 2013). The molecular stability in these environments suggest the presence of very dense gas (˜ 1023-24 cm-2) to shield the cloud of PAHs against X-ray radiation (Voit, 1992, Tielens, 2011, Sales et al., 2013). We examined the photochemistry of simple PAHs: naphtalene (C10H8), anthracene (C14H10), methyl-anthracene (C15H12) and pyrene (C16H10) at the photon energies of 275 eV, 310 eV, 1900 eV and 2500 eV in order to apply the findings at the AGN scenario. The absolute single and double photoionization and photodissociation cross sections were determined for each molecule at each energy. Their ionization and destruction induced by X-rays were examined in the conditions of the circumnuclear region of NGC 1808, a Seyfert 2 galaxy, where PAH emission was detected at 26 pc from the central object (Sales et al., 2013). It was verified the higher photostability of PAHs without functional groups attached. At higher photon energies, the results suggest a higher production yield of double charged PAHs in comparision with the single charged ones (e.g., 2 × higher for double ionized naphtalene at 2500 eV). The production of double charged molecules increase with the size of the molecules. We also discuss a minimum formation rate of PAH to balance the photodestruction rate and maintain a minimum density for their detection (e.g. 4,0× 10-7 M⊙ year-1 for a column density NH of 1023 cm-2 at 26 pc).

  12. Using deuterated PAH amendments to validate chemical extraction methods to predict PAH bioavailability in soils

    International Nuclear Information System (INIS)

    Gomez-Eyles, Jose L.; Collins, Chris D.; Hodson, Mark E.

    2011-01-01

    Validating chemical methods to predict bioavailable fractions of polycyclic aromatic hydrocarbons (PAHs) by comparison with accumulation bioassays is problematic. Concentrations accumulated in soil organisms not only depend on the bioavailable fraction but also on contaminant properties. A historically contaminated soil was freshly spiked with deuterated PAHs (dPAHs). dPAHs have a similar fate to their respective undeuterated analogues, so chemical methods that give good indications of bioavailability should extract the fresh more readily available dPAHs and historic more recalcitrant PAHs in similar proportions to those in which they are accumulated in the tissues of test organisms. Cyclodextrin and butanol extractions predicted the bioavailable fraction for earthworms (Eisenia fetida) and plants (Lolium multiflorum) better than the exhaustive extraction. The PAHs accumulated by earthworms had a larger dPAH:PAH ratio than that predicted by chemical methods. The isotope ratio method described here provides an effective way of evaluating other chemical methods to predict bioavailability. - Research highlights: → Isotope ratios can be used to evaluate chemical methods to predict bioavailability. → Chemical methods predicted bioavailability better than exhaustive extractions. → Bioavailability to earthworms was still far from that predicted by chemical methods. - A novel method using isotope ratios to assess the ability of chemical methods to predict PAH bioavailability to soil biota.

  13. Using deuterated PAH amendments to validate chemical extraction methods to predict PAH bioavailability in soils

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Eyles, Jose L., E-mail: j.l.gomezeyles@reading.ac.uk [University of Reading, School of Human and Environmental Sciences, Soil Research Centre, Reading, RG6 6DW Berkshire (United Kingdom); Collins, Chris D.; Hodson, Mark E. [University of Reading, School of Human and Environmental Sciences, Soil Research Centre, Reading, RG6 6DW Berkshire (United Kingdom)

    2011-04-15

    Validating chemical methods to predict bioavailable fractions of polycyclic aromatic hydrocarbons (PAHs) by comparison with accumulation bioassays is problematic. Concentrations accumulated in soil organisms not only depend on the bioavailable fraction but also on contaminant properties. A historically contaminated soil was freshly spiked with deuterated PAHs (dPAHs). dPAHs have a similar fate to their respective undeuterated analogues, so chemical methods that give good indications of bioavailability should extract the fresh more readily available dPAHs and historic more recalcitrant PAHs in similar proportions to those in which they are accumulated in the tissues of test organisms. Cyclodextrin and butanol extractions predicted the bioavailable fraction for earthworms (Eisenia fetida) and plants (Lolium multiflorum) better than the exhaustive extraction. The PAHs accumulated by earthworms had a larger dPAH:PAH ratio than that predicted by chemical methods. The isotope ratio method described here provides an effective way of evaluating other chemical methods to predict bioavailability. - Research highlights: > Isotope ratios can be used to evaluate chemical methods to predict bioavailability. > Chemical methods predicted bioavailability better than exhaustive extractions. > Bioavailability to earthworms was still far from that predicted by chemical methods. - A novel method using isotope ratios to assess the ability of chemical methods to predict PAH bioavailability to soil biota.

  14. Chemical and bioanalytical characterisation of PAHs in risk assessment of remediated PAH-contaminated soils.

    Science.gov (United States)

    Larsson, Maria; Hagberg, Jessika; Rotander, Anna; van Bavel, Bert; Engwall, Magnus

    2013-12-01

    Polycyclic aromatic hydrocarbons (PAHs) are common contaminants in soil at former industrial areas; and in Sweden, some of the most contaminated sites are being remediated. Generic guideline values for soil use after so-called successful remediation actions of PAH-contaminated soil are based on the 16 EPA priority pollutants, which only constitute a small part of the complex cocktail of toxicants in many contaminated soils. The aim of the study was to elucidate if the actual toxicological risks of soil samples from successful remediation projects could be reflected by chemical determination of these PAHs. We compared chemical analysis (GC-MS) and bioassay analysis (H4IIE-luc) of a number of remediated PAH-contaminated soils. The H4IIE-luc bioassay is an aryl hydrocarbon (Ah) receptor-based assay that detects compounds that activate the Ah receptor, one important mechanism for PAH toxicity. Comparison of the results showed that the bioassay-determined toxicity in the remediated soil samples could only be explained to a minor extent by the concentrations of the 16 priority PAHs. The current risk assessment method for PAH-contaminated soil in use in Sweden along with other countries, based on chemical analysis of selected PAHs, is missing toxicologically relevant PAHs and other similar substances. It is therefore reasonable to include bioassays in risk assessment and in the classification of remediated PAH-contaminated soils. This could minimise environmental and human health risks and enable greater safety in subsequent reuse of remediated soils.

  15. IRS SCAN-MAPPING OF THE WASP-WAIST NEBULA (IRAS 16253-2429). I. DERIVATION OF SHOCK CONDITIONS FROM H2 EMISSION AND DISCOVERY OF 11.3 μm PAH ABSORPTION

    International Nuclear Information System (INIS)

    Barsony, Mary; Wolf-Chase, Grace A.; Ciardi, David R.; O'Linger, JoAnn

    2010-01-01

    The outflow driven by the Class 0 protostar, IRAS 16253-2429, is associated with bipolar cavities visible in scattered mid-infrared light, which we refer to as the Wasp-Waist Nebula. InfraRed Spectometer (IRS) scan mapping with the Spitzer Space Telescope of a ∼1' x 2' area centered on the protostar was carried out. The outflow is imaged in six pure rotational (0-0 S(2) through 0-0 S(7)) H 2 lines, revealing a distinct, S-shaped morphology in all maps. A source map in the 11.3 μm polycyclic aromatic hydrocarbon (PAH) feature is presented in which the protostellar envelope appears in absorption. This is the first detection of absorption in the 11.3 μm PAH feature. Spatially resolved excitation analysis of positions in the blue- and redshifted outflow lobes, with extinction-corrections determined from archival Spitzer 8 μm imaging, shows remarkably constant temperatures of ∼1000 K in the shocked gas. The radiated luminosity in the observed H 2 transitions is found to be 1.94 ± 0.05 x 10 -5 L sun in the redshifted lobe and 1.86 ± 0.04 x 10 -5 L sun in the blueshifted lobe. These values are comparable to the mechanical luminosity of the flow. By contrast, the mass of hot (T ∼ 1000 K) H 2 gas is 7.95 ± 0.19 x 10 -7 M sun in the redshifted lobe and 5.78 ± 0.17 x 10 -7 M sun in the blueshifted lobe. This is just a tiny fraction, of order 10 -3 , of the gas in the cold (30 K), swept-up gas mass derived from millimeter CO observations. The H 2 ortho/para ratio of 3:1 found at all mapped points in this flow suggests previous passages of shocks through the gas. Comparison of the H 2 data with detailed shock models of Wilgenbus et al. shows the emitting gas is passing through Jump (J-type) shocks. Pre-shock densities of 10 4 cm -3 ≤ n H ≤ 10 5 cm -3 are inferred for the redshifted lobe and n H ≤ 10 3 cm -3 for the blueshifted lobe. Shock velocities are 5 km s -1 ≤ v s ≤ 10 km s -1 for the redshifted gas and v s = 10 km s -1 for the blueshifted gas

  16. The differences in transformation mechanism in natural and anthropogenic PAH in environmental system

    International Nuclear Information System (INIS)

    Navai, A.I.; Abasova, D.R.; Suleymanov, B.A.

    2005-01-01

    Full text : In present time, with the large reliability the established fact, that the majority of polycyclic aromatic hydrocarbons acting in an environment as from natural (fires, volcanic activity etc.) and from anthropogenesis (emissions of the industrial enterprises, the exhaust gases of automobiles etc.) sources, have carcinogenic activity. Toxicity and persistence of PAH and also their significant prevalence and their ability to be accumulated in an environment, cause necessity of the constant control most harmful polycyclic aromatic hydrocarbons in a various wide spectrum of natural matrixes - air, water, ground adjournment, ground, vegetative and animal fabrics and secretion, products of a meal. From natural sources creating a background level by PAH, is possible to note their synthesis from some plants and microorganisms, wood fires, volcanic activity and meteoric dust and etc. Anthropogenesis PAH pollution an environmental, the problem carries global character. PAH are formed as collateral products at processes of high-temperature processing of organic raw material, mainly, on oil refining, by-product-coking industry, aluminium manufactures. One of the basic sources of pollution PAH of an environment is the vehicle exhaust gases of automobiles are revealed more than 150 PAH. A significant role in PAH formation play aircraft and navigation. It is impossible to exclude an opportunity of pollution of an environment by components PAH, around and along transport pipelines. The reason to this can be oils outflow during transportation or clearing of pipelines. In the publications there is information on presence PAH in Absheron oils. But this information is not sufficient for PAI components specification. We carried out polycyclic aromatic hydrocarbons research's in oils structure of Absheron peninsula. At the first were investigated the average oils samples, which have taken from Surakhani oilfield. In Surakhani oils were found the following PAH components (in

  17. Seasonal trends in vegetation and atmospheric concentrations of PAHs and PBDEs near a sanitary landfill

    Science.gov (United States)

    St-Amand, Annick D.; Mayer, Paul M.; Blais, Jules M.

    Spruce needle and atmospheric (gaseous and particulate-bound) concentrations were surveyed near a sanitary landfill from February 2004 to June 2005. The influence of several parameters such as temperature, relative humidity, wind speed and direction, as well as increased domestic heating during the winter was assessed. In general, polybrominated diphenyl ethers (PBDE) and polycyclic aromatic hydrocarbons (PAH) concentrations in spruce needles increased over time and decreased following snowmelt with a minimum coinciding with bud burst of deciduous trees. Atmospheric concentrations of PBDE and PAH, both particulate-bound and gaseous phase, were linked to daily weather events and thus showed more variability than those in spruce needles. Highest PAH concentrations were encountered during the winter, likely reflecting increased emission from heating homes. Pseudo Clausius-Clapeyron plots revealed higher PBDE gaseous concentrations with increasing temperature, but showed no correlation between PAH gaseous concentrations and temperature as this effect was obscured by seasonal emission patterns. Finally, air mass back trajectories and local wind directions revealed that particulate-bound PBDEs, along with both gaseous and particulate-bound PAHs were from local sources, whereas gaseous PBDEs were likely from distant sources.

  18. Emission of Polycyclic Aromatic Hydrocarbons from the Exhalation Zones of Thermally Active Mine Waste Dumps

    Directory of Open Access Journals (Sweden)

    Patrycja Kuna-Gwoździewicz

    2013-01-01

    Full Text Available The article presents results of research carried out on the occurrence of polycyclic aromatic hydrocarbons (PAH in gases of exhalation zones, created on the surface of a thermally active coal mine waste dump. The oxidation and self-heating of mine waste are accompanied with the intensive emission of flue gases, including PAH group compounds. Taking into consideration the fact the hydrocarbons show strong genotoxic, mutagenic and carcinogenic properties, research was conducted to establish their content in the examined gases. The research object was a gangue dump located in Rybnik. The research was performed in 2012. In total, 24 samples of gas were collected with PUF (polyurethane foam sampling cartridges with a quartz fibre filter and an aspirator. The collected samples were analysed with the use of high performance liquid chromatography (HPLC and a fluorescence detector (FLD to evaluate the amount of PAH present.

  19. Evaluation of hydrophobicity in PAH-contaminated soils during phytoremediation

    International Nuclear Information System (INIS)

    Cofield, Naressa; Banks, M. Katherine; Schwab, A. Paul

    2007-01-01

    The impact of recalcitrant organic compounds on soil hydrophobicity was evaluated in contaminated soil from a manufactured gas plant site following 12 months of phytoremediation. Significant reduction in soil wetting and water retention was observed in contaminated soil compared to an uncontaminated control. Phytoremediation was effective at reducing total PAHs by 69% with corresponding changes in soil classification from extremely hydrophobic (initial sample) to moderately-strongly hydrophobic (planted) and hydrophilic-very hydrophilic (unplanted) after 12 months. The greatest reduction in soil hydrophobicity was observed in the unplanted, unfertilized treatments that had the lowest removal rate of PAHs. The presence of plants may contribute to hydrophobicity in contaminated soil. - The presence of recalcitrant hydrophobic organic pollutants may enhance soil hydrophobicity

  20. Heavy metals, PAHs and toxicity in stormwater wet detention ponds

    DEFF Research Database (Denmark)

    Wium-Andersen, Tove; Nielsen, Asbjørn Haaning; Hvitved-Jacobsen, Thorkild

    2011-01-01

    Concentrations of 6 different heavy metals and total Polycyclic Aromatic Hydrocarbons (PAH) were determined in stormwater runoff and in the pond water of two Danish wet detention ponds. The pond water samples were analyzed for toxic effects, using the algae Selenastrum capricornutum as a test...... organism. Stormwater and pond water from a catchment with light industry showed high levels of heavy metals, especially zinc and copper. The pond water showed high toxic effects and copper were found to be the main toxicant. Additionally, a large part of the copper was suspected to be complex bound......, reducing the potential toxicity of the metal. Another catchment (residential) produced stormwater and pond water with moderate concentration of heavy metals. The pond water occasionally showed toxic effects but no correlation between heavy metals and toxicity was identified. PAHs concentrations were...

  1. Estimation of PAHs dry deposition and BaP toxic equivalency factors (TEFs) study at Urban, Industry Park and rural sampling sites in central Taiwan, Taichung.

    Science.gov (United States)

    Fang, Guor-Cheng; Chang, Kuan-Foo; Lu, Chungsying; Bai, Hsunling

    2004-05-01

    The concentrations of polycyclic aromatic hydrocarbons (PAHs) in gas phase and particle bound were measured simultaneously at industrial (INDUSTRY), urban (URBAN), and rural areas (RURAL) in Taichung, Taiwan. And the PAH concentrations, size distributions, estimated PAHs dry deposition fluxes and health risk study of PAHs in the ambient air of central Taiwan were discussed in this study. Total PAH concentrations at INDUSTRY, URBAN, and RURAL sampling sites were found to be 1650 +/- 1240, 1220 +/- 520, and 831 +/- 427 ng/m3, respectively. The results indicated that PAH concentrations were higher at INDUSTRY and URBAN sampling sites than the RURAL sampling sites because of the more industrial processes, traffic exhausts and human activities. The estimation dry deposition and size distribution of PAHs were also studied. The results indicated that the estimated dry deposition fluxes of total PAHs were 58.5, 48.8, and 38.6 microg/m2/day at INDUSTRY, URBAN, and RURAL, respectively. The BaP equivalency results indicated that the health risk of gas phase PAHs were higher than the particle phase at three sampling sites of central Taiwan. However, compared with the BaP equivalency results to other studies conducted in factory, this study indicated the health risk of PAHs was acceptable in the ambient air of central Taiwan.

  2. Occurrence of polycyclic aromatic hydrocarbons (PAHs in beached plastic pellets from Mumbai coast, India

    Directory of Open Access Journals (Sweden)

    HB Jayasiri

    2014-06-01

    Full Text Available PAHs are a class of ubiquitous pollutants which consist of two or more fused benzene rings in various arrangements. A number of PAH compounds are known carcinogens and bioaccumulate and biomagnify. These compounds originate naturally as well as anthropogenically through oil spills, incineration of waste and combustion of fossil fuels and wood. The environmental consequence of Plastic pellets is the sorption organic pollutants on their surface from the sea surface microlayer (SML where the hydrophobic contaminants are known to be enriched. The plastic pellets were collected along the recent high tide line from four beaches of Mumbai coast bimonthly during May 2011 - March 2012. A total of 72 pools of plastic pellets were extracted, fractionated and analysed by Gas Chromatograph coupled to a mass spectrometer to evaluate the extent and sources of 16 PAHs. The mean ΣPAH concentration in pellets was 9202.30±114.89 ng g-1 with a wide range (35.4-46191.58 ng g-1. The concentration of fluorene was found to be the highest (1606.30±251.54 ng g-1 followed by anthracene, chrysene and phenanthrene. The ΣPAH concentration was significantly varied among months and there was no significant difference among sites at  p=0.05. The 2-3 aromatic ring compounds accounted for 60% of the total PAHs in pellets of Mumbai coast while 4 rings and 5-6 rings compounds accounted for 26 and 14%, respectively. The ratio of low and high molecular weight PAHs indicated that the contamination by petrogenic sources was predominant over the pyrogenic ones in plastic pellets suggesting oil pollution in coastal area of Mumbai.Keywords: plastic pellets, PAHs, Mumbai, sources

  3. Urban sprawl leaves its PAH signature

    Science.gov (United States)

    Van Metre, P.C.; Mahler, B.J.; Furlong, E.T.

    2000-01-01

    The increasing vehicle traffic associated with urban sprawl in the United States is frequently linked to degradation of air quality, but its effect on aquatic sediment is less well-recognized. This study evaluates trends in PAHs, a group of contaminants with multiple urban sources, in sediment cores from 10 reservoirs and lakes in six U.S. metropolitan areas. The watersheds chosen represent a range in degree and age of urbanization. Concentrations of PAHs in all 10 reservoirs and lakes increased during the past 20-40 years. PAH contamination of the most recently deposited sediment at all sites exceeded sediment-quality guidelines established by Environment Canada, in some cases by several orders of magnitude. These results add a new chapter to the story told by previous coring studies that reported decreasing concentrations of PAHs after reaching highs in the 1950s. Concurrent with the increase in concentrations is a change in the assemblage of PAHs that indicates the increasing trends are driven by combustion sources. The increase in PAH concentrations tracks closely with increases in automobile use, even in watersheds that have not undergone substantial changes in urban land-use levels since the 1970s.The increasing vehicle traffic associated with urban sprawl in the United States is frequently linked to degradation of air quality, but its effect on aquatic sediment is less well-recognized. This study evaluates trends in PAHs, a group of contaminants with multiple urban sources, in sediment cores from 10 reservoirs and lakes in six U.S. metropolitan areas. The watersheds chosen represent a range in degree and age of urbanization. Concentrations of PAHs in all 10 reservoirs and lakes increased during the past 20-40 years. PAH contamination of the most recently deposited sediment at all sites exceeded sediment-quality guidelines established by Environment Canada, in some cases by several orders of magnitude. These results add a new chapter to the story told by

  4. PAH distribution and mass fluxes in the Three Gorges Reservoir after impoundment of the Three Gorges Dam.

    Science.gov (United States)

    Deyerling, Dominik; Wang, Jingxian; Hu, Wei; Westrich, Bernhard; Peng, Chengrong; Bi, Yonghong; Henkelmann, Bernhard; Schramm, Karl-Werner

    2014-09-01

    Mass fluxes of polycyclic aromatic hydrocarbons (PAHs) were calculated for the Three Gorges Reservoir (TGR) in China, based on concentration and discharge data from the Yangtze River. Virtual Organisms (VOs) have been applied during four campaigns in 2008, 2009 (twice) and 2011 at sampling sites distributed from Chongqing to Maoping. The total PAH mass fluxes ranged from 110 to 2,160 mg s(-1). Highest loads were determined at Chongqing with a decreasing trend towards Maoping in all four sampling campaigns. PAH remediation capacity of the TGR was found to be high as the mass flux reduced by more than half from upstream to downstream. Responsible processes are thought to be adsorption of PAH to suspended particles, dilution and degradation. Furthermore, the dependence of PAH concentration upon water depth was investigated at Maoping in front of the Three Gorges Dam. Although considerable differences could be revealed, there was no trend observable. Sampling of water with self-packed filter cartridges confirmed more homogenous PAH depth distribution. Moreover, PAH content of suspended particles was estimated from water concentrations gathered by VOs based on a water-particle separation model and subsequently compared to PAH concentration measured in water and in filter cartridges. It could be shown that the modeled data predicts the concentration caused by particle-bound PAHs to be about 6 times lower than PAHs dissolved in water. Besides, the model estimates the proportions of 5- and 6-ring PAHs being higher than in water phase. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. PAH effects on meio- and microbial benthic communities strongly depend on bioavailability.

    Science.gov (United States)

    Lindgren, J Fredrik; Hassellöv, Ida-Maja; Dahllöf, Ingela

    2014-01-01

    The effects of anthropogenic pollutants in dissimilar habitats can vary depending on differences in bioavailability. The factors determining bioavailability are not yet fully understood. This study was performed to evaluate whether analysis of total PAH concentrations in sediments is a satisfactory measurement to indicate environmental effects or if bioavailability is needed to be taken into account. We have here performed a 60-day experiment, where nominal PAH concentrations of 1,300 μg/kg sediment were added to three different marine sediments. Meiofaunal and microbial communities were analyzed for alterations in community response at 30 and 60 days. Results showed that bioavailability of PAHs varied between the three different sediments. Nonetheless, the petroleum addition gave rise to significant negative effects on all three sediments at both time points. The two direct measurements of toxicity on the microbial community, potential nitrification and denitrification, displayed a lower effect of the PAH addition in the muddy sediment at both time points, compared to the other two sediment types. No effects were seen in the analysis of meiofaunal community structure. Measurements of PAH bioavailability in the three sediment types concurred with the results from the microbial community, revealing a lower bioavailability in the muddy sediment compared to the other two sediment types, 34% compared to sandy and 18% compared to organic at day 0. At day 60 it was 61% lower compared to sandy and 20% lower compared to organic. The negative effects of the PAH addition on the microbial nitrogen cycle were in six out of eight cases best correlated to the amount of alkylated bioavailable PAH in the sediments, and thus microbial nitrogen cycle is a possible good indicator for assessing PAH-induced stress. The results presented here have implications for risk analysis studies of petroleum-contaminated marine sediments; consequently, sediment characteristics and its effects on

  6. A PAH growth mechanism and synergistic effect on PAH formation in counterflow diffusion flames

    KAUST Repository

    Wang, Yu

    2013-09-01

    A reaction mechanism having molecular growth up to benzene for hydrocarbon fuels with up to four carbon-atoms was extended to include the formation and growth of polycyclic aromatic hydrocarbons (PAHs) up to coronene (C24H12). The new mechanism was tested for ethylene premixed flames at low (20torr) and atmospheric pressures by comparing experimentally observed species concentrations with those of the computed ones for small chemical species and PAHs. As compared to several existing mechanisms in the literature, the newly developed mechanism showed an appreciable improvement in the predicted profiles of PAHs. The new mechanism was also used to simulate PAH formation in counterflow diffusion flames of ethylene to study the effects of mixing propane and benzene in the fuel stream. In the ethylene-propane flames, existing experimental results showed a synergistic effect in PAH concentrations, i.e. PAH concentrations first increased and then decreased with increasing propane mixing. This PAH behavior was successfully captured by the new mechanism. The synergistic effect was predicted to be more pronounced for larger PAH molecules as compared to the smaller ones, which is in agreement with experimental observations. In the experimental study in which the fuel stream of ethylene-propane flames was doped with benzene, a synergistic effect was mitigated for benzene, but was observed for large PAHs. This effect was also predicted in the computed PAH profiles for these flames. To explain these responses of PAHs in the flames of mixture fuels, a pathway analysis has been conducted, which show that several resonantly stabilized species as well as C4H4 and H atom contribute to the enhanced synergistic behaviors of larger PAHs as compared to the small ones in the flames of mixture fuels. © 2013 The Combustion Institute.

  7. Effects of combustion temperature on air emissions and support fuel consumption in full scale fluidized bed sludge incineration: with particular focus on nitrogen oxides and total organic carbon.

    Science.gov (United States)

    Löschau, Margit

    2018-04-01

    This article describes a pilot test at a sewage sludge incineration plant and shows its results considering the impacts of reducing the minimum combustion temperature from 850°C to 800°C. The lowering leads to an actual reduction of the average combustion temperature by 25 K and a significant reduction in the fuel oil consumption for support firing. The test shall be used for providing evidence that the changed combustion conditions do not result in higher air pollutant emissions. The analysis focusses on the effects of the combustion temperature on nitrogen oxides (NO x ) and total organic carbon emissions. The evaluation of all continuously monitored emissions shows reduced emission levels compared to the previous years, especially for NO x .

  8. Determination of polynuclear aromatic hydrocarbons (PAHs) in ...

    African Journals Online (AJOL)

    AJB SERVER

    2006-11-02

    Nov 2, 2006 ... Several water bodies in the Niger Delta region of Nigeria where extensive crude oil ..... hydrocarbons (PAHs) in fish from the Red Sea Coast of Yemem. ... smoked meat products and smoke flavouring food additives. J.

  9. Calculation of total cross sections and effective emission coefficients for B5+ collisions with ground-state and excited hydrogen

    International Nuclear Information System (INIS)

    Guzman, F; Errea, L F; Illescas, Clara; Mendez, L; Pons, B

    2010-01-01

    Classical and semiclassical calculations of nl-resolved charge exchange cross sections in B 5 + collisions with H(n i ) are performed to compute effective emission coefficients for the n = 7 → n = 6 transition in B 4 + for plasma conditions typical of the ASDEX-U tokamak. For n i = 1, the value of the emission coefficient is larger than that obtained from ADAS database by a factor of 2 at energies of 10 keV amu -1 , but no differences are found at energies above 50 keV amu -1 . For n i = 2, our calculation yields emission coefficients close to those derived from ADAS data from low to high impact energies. The emission coefficients corresponding to B 5 + + H(n i = 3) collisions are of the same order of magnitude as those for n i = 2.

  10. Characterization of Intrinsic PAH Biodegradation in Groundwater During Tidal Cycles at the Naval Station Norfolk: Interim Report

    National Research Council Canada - National Science Library

    Boyd, Thomas

    2002-01-01

    .... Groundwater at the site is impacted by subsurface fuel spill(s). Groundwater was assessed for fuel hydrocarbon concentrations, stable carbon isotope fingerprints, temperature, salinity, total microbial carbon demand, and PAH mineralization rates...

  11. Low accessibility and chemical activity of PAHs restrict bioremediation and risk of exposure in a manufactured gas plant soil

    International Nuclear Information System (INIS)

    Reichenberg, Fredrik; Karlson, Ulrich Gosewinkel; Gustafsson, Orjan; Long, Sara M.; Pritchard, Parmely H.; Mayer, Philipp

    2010-01-01

    Composting of manufactured gas plant soil by a commercial enterprise had removed most of its polycyclic aromatic hydrocarbons (PAHs), but concentrations remained above regulatory threshold levels. Several amendments and treatments were first tested to restart the PAH degradation, albeit with little success. The working hypothesis was then that PAHs were 'stuck' due to strong sorption to black carbon. Accessibility was measured with cyclodextrin extractions and on average only 4% of the PAHs were accessible. Chemical activity of the PAHs was measured by equilibrium sampling, which confirmed a low exposure level. These results are consistent with strong sorption to black carbon (BC), which constituted 59% of the total organic carbon. Composting failed to remove the PAHs, but it succeeded to minimize PAH accessibility and chemical activity. This adds to accumulating evidence that current regulatory thresholds based on bulk concentrations are questionable and alternative approaches probing actual risk should be considered. - Bioremediation of MGP soil failed to eliminate PAHs but it succeeded to limit their accessibility, chemical activity and the remaining risk of biological exposure.

  12. Source characterization using compound composition and stable carbon isotope ratio of PAHs in sediments from lakes, harbor, and shipping waterway

    International Nuclear Information System (INIS)

    Kim, Moonkoo; Kennicutt, Mahlon C.; Qian, Yaorong

    2008-01-01

    Molecular compositions and compound specific stable carbon isotope ratios of polycyclic aromatic hydrocarbons (PAH) isolated from sediments were used to characterize possible sources of contamination at an urban lake, a harbor, a shipping waterway, and a relatively undisturbed remote lake in the northwest United States. Total PAH concentrations in urban lake sediments ranged from 66.0 to 16,500 μg g -1 dry wt. with an average of 2600 μg g -1 , which is ∼ 50, 100, and 400 times higher on average than PAH in harbor (48 μg g -1 on average), shipping waterway (26 μg g -1 ), and remote lake (7 μg g -1 ) sediments, respectively. The PAH distribution patterns, methyl phenanthrene/phenanthrene ratios, and a pyrogenic index at the sites suggest a pyrogenic origin for PAHs. Source characterization using principal component analysis and various molecular indices including C2-dibenzothiophenes/C2-phenanthrenes, C3-dibenzothiophenes/C3-phenanthrenes, and C2-chrysenes/C2-phenanthrenes ratios, was able to differentiate PAH deposited in sediments from the four sites. The uniqueness of the source of the sediment PAHs from urban lake was also illustrated by compound specific stable carbon isotope analysis. It was concluded that urban lake sediments are accumulating PAH from sources that are unique from contamination detected at nearby sites in the same watershed

  13. Response of PAH-degrading genes to PAH bioavailability in the overlying water, suspended sediment, and deposited sediment of the Yangtze River.

    Science.gov (United States)

    Xia, Xinghui; Xia, Na; Lai, Yunjia; Dong, Jianwei; Zhao, Pujun; Zhu, Baotong; Li, Zhihuang; Ye, Wan; Yuan, Yue; Huang, Junxiong

    2015-06-01

    The degrading genes of hydrophobic organic compounds (HOCs) serve as indicators of in situ HOC degradation potential, and the existing forms and bioavailability of HOCs might influence the distribution of HOC-degrading genes in natural waters. However, little research has been conducted to study the relationship between them. In the present study, nahAc and nidA genes, which act as biomarkers for naphthalene- and pyrene-degrading bacteria, were selected as model genotypes to investigate the response of polycyclic aromatic hydrocarbon (PAH)-degrading genes to PAH bioavailability in the overlying water, suspended sediment (SPS), and deposited sediment of the Yangtze River. The freely dissolved concentration, typically used to reflect HOC bioavailability, and total dissolved, as well as sorbed concentrations of PAHs were determined. Phylogenetic analysis showed that all the PAH-ring hydroxylating dioxygenase gene sequences of Gram-negative bacteria (PAH-RHD[GN]) were closely related to nahAc, nagAc, nidA, and uncultured PAH-RHD genes. The PAH-RHD[GN] gene diversity as well as nahAc and nidA gene copy numbers decreased in the following order: deposited sediment>SPS>overlying water. The nahAc and nidA gene abundance was not significantly correlated with environmental parameters but was significantly correlated with the bioavailable existing forms of naphthalene and pyrene in the three phases. The nahAc gene copy numbers in the overlying water and deposited sediment were positively correlated with freely dissolved naphthalene concentrations in the overlying and pore water phases, respectively, and so were nidA gene copy numbers. This study suggests that the distribution and abundance of HOC-degrading bacterial population depend on the HOC bioavailability in aquatic environments. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Elucidating the urban levels, sources and health risks of polycyclic aromatic hydrocarbons (PAHs) in Pakistan: Implications for changing energy demand.

    Science.gov (United States)

    Hamid, Naima; Syed, Jabir Hussain; Junaid, Muhammad; Mahmood, Adeel; Li, Jun; Zhang, Gan; Malik, Riffat Naseem

    2018-04-01

    Due to the severe fuel crisis in terms of natural gas, a paradigm shift in fuel combustion (diesel, gasoline, and biomass) may increase the atmospheric emissions and associated health risks in Pakistan. Present study was aimed to investigate the concentration of fugitive PAHs in the environment (outdoor and indoor settings), associated probabilistic health risk assessment in the exposed population, and possible linkage between fuel consumption patterns and PAHs emissions in twin cities (Rawalpindi and Islamabad) of Pakistan. Results showed that the mean PAHs concentrations (air: 2390pgm -3 ; dust: 167ngg -1 ) in the indoor environment were higher than that of the outdoor environment (air: 2132pgm -3 ; dust: 90.0ngg -1 ). Further, the source apportionment PCA-MLR receptor model identified diesel and gasoline combustion as the primary PAHs sources in the urban and sub-urban settings. Estimated life cancer risk (LCR) potential via inhalation to indoor PAHs was higher with a probability of 2.0 cases per 10,000 inhabitants as compared to outdoor exposure. Incremental lifetime cancer risk (ILCR) model from exposure to dust bound PAHs showed risk in the order of ingestion>dermal>inhalation for various exposure pathways. Likewise, estimated daily intake (EDI) model reflects that PAHs in surface dust enter into the human body mainly through the respiratory system because EDI for breathing was reported higher than that of oral intake. Therefore, adoption of sustainable fuels is recommended to meet the energy requirements and to reduce PAHs emissions and related health risks in the twin cities of Pakistan. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Analysis of PAH in soil samples

    International Nuclear Information System (INIS)

    Haeufel, J.; Weisweiler, W.

    1994-01-01

    The supercritical fluid extraction of polycyclic aromatic hydrocarbons (PAH) from soil samples is described. Carbon dioxide mixed with a small amount of methanol is used for solvent. The results are compared with those obtained by a classical extraction method (that means with the use of organic liquids). The extracted PAH from both procedures can be separated by HPLC and analyzed with UV- and fluorescence detection. (orig.) [de

  16. Microorganism selection and performance in bioslurry reactors treating PAH-contaminated soil.

    Science.gov (United States)

    Cassidy, D P; Hudak, A J

    2002-09-01

    A continuous-flow reactor (CSTR) and a soil slurry-sequencing batch reactor (SS-SBR) were operated in 81 vessels for 200 days to treat a soil contaminated with polycyclic aromatic hydrocarbons (PAH). Filtered slurry samples were used to quantify bulk biosurfactant concentrations and PAH emulsification. Concentrations of Corynebacterium aquaticum, Flavobacterium mizutaii, Mycobacterium gastri, Pseudomonas aeruginosa, and Pseudomonas putida were determined using fatty acid methyl ester (FAME) analysis. The CSTR and SS-SBR selected microbial consortia with markedly different surfactant-producing and PAH-degrading abilities. Biosurfactant levels in the SS-SBR reached 4 times the critical micelle concentration (CMC) that resulted in considerable emulsification of PAH. In contrast, CSTR operation resulted in nomeasurable biosurfactant production. Total PAH removal efficiency was 93% in the SS-SBR, compared with only 66% in the CSTR, and stripping of PAH was 3 times less in the SS-SBR. Reversing the mode of operation on day 100 caused a complete reversal in microbial consortia and in reactor performance by day 140. These results show that bioslurry reactor operation can be manipulated to control overall reactor performance.

  17. Concentrations, input prediction and probabilistic biological risk assessment of polycyclic aromatic hydrocarbons (PAHs) along Gujarat coastline.

    Science.gov (United States)

    Gosai, Haren B; Sachaniya, Bhumi K; Dudhagara, Dushyant R; Rajpara, Rahul K; Dave, Bharti P

    2018-04-01

    A comprehensive investigation was conducted in order to assess the levels of PAHs, their input prediction and potential risks to bacterial abundance and human health along Gujarat coastline. A total of 40 sediment samples were collected at quarterly intervals within a year from two contaminated sites-Alang-Sosiya Shipbreaking Yard (ASSBRY) and Navlakhi Port (NAV), situated at Gulf of Khambhat and Gulf of Kutch, respectively. The concentration of ΣPAHs ranged from 408.00 to 54240.45 ng g -1  dw, indicating heavy pollution of PAHs at both the contaminated sites. Furthermore, isomeric ratios and principal component analysis have revealed that inputs of PAHs at both contaminated sites were mixed-pyrogenic and petrogenic. Pearson co-relation test and regression analysis have disclosed Nap, Acel and Phe as major predictors for bacterial abundance at both contaminated sites. Significantly, cancer risk assessment of the PAHs has been exercised based on incremental lifetime cancer risks. Overall, index of cancer risk of PAHs for ASSBRY and NAV ranged from 4.11 × 10 -6 -2.11 × 10 -5 and 9.08 × 10 -6 -4.50 × 10 -3 indicating higher cancer risk at NAV compared to ASSBRY. The present findings provide baseline information that may help in developing advanced bioremediation and bioleaching strategies to minimize biological risk.

  18. Source apportionment of elevated wintertime PAHs by compound-specific radiocarbon analysis

    Directory of Open Access Journals (Sweden)

    R. J. Sheesley

    2009-05-01

    Full Text Available Natural abundance radiocarbon analysis facilitates distinct source apportionment between contemporary biomass/biofuel (14C "alive" versus fossil fuel (14C "dead" combustion. Here, the first compound-specific radiocarbon analysis (CSRA of atmospheric polycyclic aromatic hydrocarbons (PAHs was demonstrated for a set of samples collected in Lycksele, Sweden a small town with frequent episodes of severe atmospheric pollution in the winter. Renewed interest in using residential wood combustion (RWC means that this type of seasonal pollution is of increasing concern in many areas. Five individual/paired PAH isolates from three pooled fortnight-long filter collections were analyzed by CSRA: phenanthrene, fluoranthene, pyrene, benzo[b+k]fluoranthene and indeno[cd]pyrene plus benzo[ghi]perylene; phenanthrene was the only compound also analyzed in the gas phase. The measured Δ14C for PAHs spanned from −138.3‰ to 58.0‰. A simple isotopic mass balance model was applied to estimate the fraction biomass (fbiomass contribution, which was constrained to 71–87% for the individual PAHs. Indeno[cd]pyrene plus benzo[ghi]perylene had an fbiomass of 71%, while fluoranthene and phenanthrene (gas phase had the highest biomass contribution at 87%. The total organic carbon (TOC, defined as carbon remaining after removal of inorganic carbon fbiomass was estimated to be 77%, which falls within the range for PAHs. This CSRA data of atmospheric PAHs established that RWC is the dominating source of atmospheric PAHs to this region of the boreal zone with some variations among RWC contributions to specific PAHs.

  19. Source and Ecological Risk Characteristics of PAHs in Sediments from Qinhuai River and Xuanwu Lake, Nanjing, China

    Directory of Open Access Journals (Sweden)

    Zhenhua Zhao

    2017-01-01

    Full Text Available In order to investigate the residual characteristics, sources, and ecological risk of PAHs in sediment from urban rivers, the sediments of 15 typical sites from Qinhuai River and Xuanwu Lake, which are typical urban rivers and lake, were collected from October 2015 to July 2016; the sources of PAHs in sediment were also identified by several methods. Results showed that ∑PAHs concentration in sediment ranged from 796.2 ng/g to 10,470 ng/g with an average of 2,713.8 ng/g. High molecular weight PAHs with 4-5 rings were most prominent in the sediment during all four seasons. Source characterization studies based on the analysis of diagnostic ratio (triangular plot method, cluster analysis, and positive factor matrix analysis suggested that the PAHs of Qinhuai River Basin were mainly from pyrogenic origin (biomass and coal combustion and vehicular emission, and the petroleum source also cannot be ignored (specially in summer. Most individual PAHs occasionally affect the aquatic organisms. The highest benzo[a]pyrene-equivalent doses (BaPeq dose appear at the sites of sewage discharge and heavy traffic. So, the PAHs pollution sources of urban water body have obvious seasonal-dependent and human activities-dependent characteristics.

  20. Polycyclic aromatic hydrocarbons (PAHs) in continental shelf sediment of China: implications for anthropogenic influences on coastal marine environment.

    Science.gov (United States)

    Liu, Liang-Ying; Wang, Ji-Zhong; Wei, Gao-Ling; Guan, Yu-Feng; Zeng, Eddy Y

    2012-08-01

    Sediments collected from the continental shelf of China, embracing Yellow Sea, inner shelf of the East China Sea (ECS), and the South China Sea (SCS), were analyzed for polycyclic aromatic hydrocarbons (PAHs). The concentrations of anthropogenic PAHs (Σ(18)PAH) were 27-224 ng/g dry weight, with an average of 82 ng/g. Sedimentary PAHs in the continental shelf off China were mainly derived from mixed residues of biomass, coal, and petroleum combustion. Fluvial transport and atmospheric deposition mainly accounted for sediment PAHs in the ECS inner shelf and Yellow Sea (and the SCS), respectively. Furthermore, statistically higher levels of Σ(18)PAH (28-224 ng/g; mean 110 ng/g) in the Yellow Sea sediment than in the SCS sediment (28-109 ng/g; mean 58 ng/g) were probably resulted from higher PAH emissions from coke industry and domestic coal combustion in North China than in South China. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Influence of continental organic aerosols to the marine atmosphere over the East China Sea: Insights from lipids, PAHs and phthalates.

    Science.gov (United States)

    Kang, Mingjie; Yang, Fan; Ren, Hong; Zhao, Wanyu; Zhao, Ye; Li, Linjie; Yan, Yu; Zhang, Yingjie; Lai, Senchao; Zhang, Yingyi; Yang, Yang; Wang, Zifa; Sun, Yele; Fu, Pingqing

    2017-12-31

    Total suspended particle (TSP) samples were collected during a marine cruise in the East China Sea from May 18 to June 12, 2014. They were analyzed for solvent extractable organic compounds (lipid compounds, PAHs and phthalates) using gas chromatography/mass spectrometry (GC/MS) to better understand the sources and source apportionment of aerosol pollution in the western North Pacific. Higher concentrations were observed in the terrestrially influenced aerosol samples on the basis of five-day backward air mass trajectories, especially for aerosols collected near coastal areas. Phthalates were found to be the dominant species among these measured compound classes (707±401ngm -3 for daytime and 313±155ngm -3 for nighttime), followed by fatty acids, fatty alcohols, n-alkanes and PAHs. In general, the daytime abundances for these compounds are higher than nighttime, possibly attributable to more intensive anthropogenic activities during the daytime. The factor analysis indicates that biomass burning, fungal activities and fossil fuel combustion maybe the main emission sources for organic aerosols over the East China Sea. This study demonstrates that the East Asian continent can be a natural emitter of biogenic and anthropogenic organics to the marine atmosphere through long-range transport, which controls the chemical composition and concentration of organic aerosols over the East China Sea. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Investigations of Flare Gas Emissions in Taq Taq Oil Field on the Surrounding Land

    Directory of Open Access Journals (Sweden)

    Jafar A. Ali

    2014-11-01

    Full Text Available Environmental pollution caused by oil takes many different forms; one of the most damaging sources is simply the combustion of oil products, such as a well flare burn-off. This paper presents the results of a survey of the agriculture lands around the Taq Taq Oil Production Company. The aim of the survey was to determine the potential contamination caused by the gas emissions from the well flares. Taq Taq field is located in the Kurdistan Region of Iraq, 60 km north of the giant Kirkuk oil field, 85 km south-east of Erbil and 120 km north-west of Suleimani. Samples of soil were collected from several locations around the site and analyzed to determine the content of Polycyclic Aromatic Hydrocarbons PAH present. A gas chromatography linked to a mass spectrometry (GCMS machine was used for these measurements. The PAH contamination at each location of soil was determined and the 16-PAHs, as listed in the US Environmental Protection Agency (EPA documentation were investigated. The average content of total PAH in all samples of the agricultural soil was 0.654 mg·kg-1 with the concentrations ranging from 0.310 to 0.869 mg·kg-1. It was found that the PAH concentrations decreased with increasing distance from the TTOPCO oil field, indicating that pollution was evident, the area close to the field being more affected by the gas pollution.

  3. Evaluating the effectiveness of carbon tax for total emission control of carbon dioxide. Systems analysis of a dynamic environmental-economic model

    International Nuclear Information System (INIS)

    Tamura, Hiroyuki; Abe, Makoto; Tomiyama, Shinji; Hatono, Itsuo

    1999-01-01

    This paper deals with how to evaluate the effectiveness of carbon tax (environmental tax) for regulating the carbon dioxide emissions. For this purpose we mainly deal with a primal problem and its dual problem of dynamic linear programming model. The primal problem is formulated by using Leontief type input-output model and the basic idea of commodity stocks. It represents the balance of materials. The dual problem is obtained and interpreted as cash balance. It is clarified in this paper whether the carbon tax is effective to decrease the total amount of carbon dioxide emissions. (author)

  4. Properties of polycyclic aromatic hydrocarbons in the northwest photon dominated region OF NGC 7023. I. PAH size, charge, composition, and structure distribution

    International Nuclear Information System (INIS)

    Boersma, C.; Bregman, J. D.; Allamandola, L. J.

    2013-01-01

    Polycyclic aromatic hydrocarbon (PAH) emission in the Spitzer Infrared Spectrograph spectral map of the northwest photon dominated region (PDR) in NGC 7023 was analyzed exclusively using PAH spectra from the NASA Ames PAH IR Spectroscopic Database (www.astrochem.org/pahdb). The 5-15 μm spectrum at each pixel is fitted using a non-negative-least-squares fitting approach. The fits are of good quality, allowing decomposition of the PAH emission into four subclasses: size, charge, composition, and hydrogen adjacency (structure). Maps tracing PAH subclass distributions across the region paint a coherent astrophysical picture. Once past some 20 seconds of arc from HD 200775, the emission is dominated by the more stable, large, symmetric, compact PAH cations with smaller, neutral PAHs taking over along the lines-of-sight toward the more distant molecular cloud. The boundary between the PDR and the denser cloud material shows up as a distinct discontinuity in the breakdown maps. Noteworthy is the requirement for PANH cations to fit the bulk of the 6.2 and 11.0 μm features and the indication of PAH photo-dehydrogenation and fragmentation close to HD 200775. Decomposition of the spectral maps into 'principal' subclass template spectra provides additional insight into the behavior of each subclass. However, the general applicability of this computationally more efficient approach is presently undetermined. This is the first time the spectra of individual PAHs are exclusively used to fit the 5-15 μm region and analyze the spatial behavior of the aromatic infrared bands, providing fundamental, new information about astronomical PAH subpopulations including their dependence on, and response to, changes in local conditions.

  5. Properties of polycyclic aromatic hydrocarbons in the northwest photon dominated region OF NGC 7023. I. PAH size, charge, composition, and structure distribution

    Energy Technology Data Exchange (ETDEWEB)

    Boersma, C.; Bregman, J. D.; Allamandola, L. J., E-mail: Christiaan.Boersma@nasa.gov [NASA Ames Research Center, MS 245-6, Moffett Field, CA 94035-0001 (United States)

    2013-06-01

    Polycyclic aromatic hydrocarbon (PAH) emission in the Spitzer Infrared Spectrograph spectral map of the northwest photon dominated region (PDR) in NGC 7023 was analyzed exclusively using PAH spectra from the NASA Ames PAH IR Spectroscopic Database (www.astrochem.org/pahdb). The 5-15 μm spectrum at each pixel is fitted using a non-negative-least-squares fitting approach. The fits are of good quality, allowing decomposition of the PAH emission into four subclasses: size, charge, composition, and hydrogen adjacency (structure). Maps tracing PAH subclass distributions across the region paint a coherent astrophysical picture. Once past some 20 seconds of arc from HD 200775, the emission is dominated by the more stable, large, symmetric, compact PAH cations with smaller, neutral PAHs taking over along the lines-of-sight toward the more distant molecular cloud. The boundary between the PDR and the denser cloud material shows up as a distinct discontinuity in the breakdown maps. Noteworthy is the requirement for PANH cations to fit the bulk of the 6.2 and 11.0 μm features and the indication of PAH photo-dehydrogenation and fragmentation close to HD 200775. Decomposition of the spectral maps into 'principal' subclass template spectra provides additional insight into the behavior of each subclass. However, the general applicability of this computationally more efficient approach is presently undetermined. This is the first time the spectra of individual PAHs are exclusively used to fit the 5-15 μm region and analyze the spatial behavior of the aromatic infrared bands, providing fundamental, new information about astronomical PAH subpopulations including their dependence on, and response to, changes in local conditions.

  6. Properties of Polycyclic Aromatic Hydrocarbons in the Northwest Photon Dominated Region of NGC 7023. I. PAH Size, Charge, Composition, and Structure Distribution

    Science.gov (United States)

    Boersma, C.; Bregman, Jesse; Allamandola, L. J

    2013-01-01

    Polycyclic aromatic hydrocarbon (PAH) emission in the Spitzer Infrared Spectrograph spectral map of the northwest photon dominated region (PDR) in NGC 7023 was analyzed exclusively using PAH spectra from the NASA Ames PAH IR Spectroscopic Database (www.astrochem.org/pahdb). The 5-15 micron spectrum at each pixel is fitted using a non-negative-least-squares fitting approach. The fits are of good quality, allowing decomposition of the PAH emission into four subclasses: size, charge, composition, and hydrogen adjacency (structure). Maps tracing PAH subclass distributions across the region paint a coherent astrophysical picture. Once past some 20 seconds of arc from HD 200775, the emission is dominated by the more stable, large, symmetric, compact PAH cations with smaller, neutral PAHs taking over along the lines-of-sight toward the more distant molecular cloud. The boundary between the PDR and the denser cloud material shows up as a distinct discontinuity in the breakdown maps. Noteworthy is the requirement for PANH cations to fit the bulk of the 6.2 and 11.0 micron features and the indication of PAH photo-dehydrogenation and fragmentation close to HD 200775. Decomposition of the spectral maps into "principal" subclass template spectra provides additional insight into the behavior of each subclass. However, the general applicability of this computationally more efficient approach is presently undetermined. This is the first time the spectra of individual PAHs are exclusively used to fit the 5-15 micron region and analyze the spatial behavior of the aromatic infrared bands, providing fundamental, new information about astronomical PAH subpopulations including their dependence on, and response to, changes in local conditions.

  7. Lead and polycyclic aromatic hydrocarbons (PAHs) in surface soil from day care centres in the city of Bergen, Norway

    International Nuclear Information System (INIS)

    Haugland, Toril; Ottesen, Rolf Tore; Volden, Tore

    2008-01-01

    Surface soil (0-2 cm) quality in 87 day care centres in the city of Bergen, Norway has been studied. Approximately 45% of the day care centres contained Pb and PAH values above recommended action levels. There are clear variations between different areas of the city. The old central part of the city hosts most of the contaminated day care centres. In suburban areas most of the day care centres have Pb and PAH concentrations below action levels. City fires, gas work emission, lead-based paint, and traffic are probably important anthropogenic contamination sources, together with uncontrolled transportation of soil from contaminated to clean areas. Geological or other natural sources are probably not an important contributor to the high levels of lead and PAH. - Surface soil in 45% of the studied day care centres was contaminated by lead and PAH

  8. Personal exposure to particulate PAHs and anthraquinone and oxidative DNA damages in humans.

    Science.gov (United States)

    Wei, Yongjie; Han, In-Kyu; Hu, Min; Shao, Min; Zhang, Junfeng Jim; Tang, Xiaoyan

    2010-11-01

    Recent studies suggest that DNA oxidative damage be related to the chemical constituents of ambient particles. The purpose of this study was to examine whether particulate polycyclic aromatic hydrocarbons (PAHs) and quinone-structure chemicals increase body burden of oxidative stress in human exposed to heavy traffic volume. We recruited two nonsmoking security guards who worked at a university campus gate near a heavily trafficked road. Each subject wore a personal air sampler for 24h per day to estimate exposures to 24 PAHs and anthraquinone (AnQ) in PM(2.5). Daily pre- and post-work shift spot urines were collected for 29d from each subject. Urine samples were analyzed for 8-hydroxy-2'-deoxyguanosine (8-OHdG). Additionally, using 19 organic tracers other than 24 PAHs and AnQ, a receptor source apportionment model of chemical mass balance was applied to determine the contributions of sources on the PM: gasoline vehicle, diesel vehicle, coal burning, vegetable debris, cooking, natural gas and biomass burning. The relationship among urinary 8-OHdG, individual PAH, and AnQ was demonstrated as follows: the average urinary concentration of 8-OHdG was increased more than three times after 8-h work-shift than those before the work shift. All the 24 PAH and AnQ levels were positively and significantly associated with the post-work urinary 8-OHdG. The results from source apportionment suggest vehicular emission to be the dominant source of personal exposure to PM(2.5). Our finding indicates that personal air exposures to 24 individual PAHs and AnQ originating from traffic emissions are important in increasing oxidative burdens in human body. Copyright © 2010 Elsevier Ltd. All rights reserved.

  9. Environmental assessment of polycyclic aromatic hydrocarbons (PAHs) in surface sediments of the Santander Bay, Northern Spain.

    Science.gov (United States)

    Viguri, J; Verde, J; Irabien, A

    2002-07-01

    Samples of intertidal surface sediments (0-2 cm) were collected in 17 stations of the Santander Bay, Cantabric Sea, Northern Spain. The concentrations of polycyclic aromatic hydrocarbons (PAHs), 16, were analysed by HPLC and MS detection. Surface sediments show a good linear correlation among the parameters of the experimental organic matter evaluation, where total carbon (TC) and loss on ignition (LOI) are approximately 2.5 and 5 times total organic carbon (TOC). A wide range of TOC from 0.08% to 4.1%, and a broad distribution of the sum of sigma16PAHs, from 0.02 to 344.6 microg/g d.w., which can be correlated by an exponential equation to the TOC, has been identified. A qualitative relationship may be established between the industrial input along the rivers and the concentration of sigma6PAHs in the sediments of the estuaries: Boo estuary (8404-4631 microg/g OC), Solia-San Salvador estuaries (305-113 microg/g OC) and Cubas estuary (31-32 microg/g OC). This work shows a dramatic change in the spatial distribution in the concentration of PAHs of intertidal surface sediments. The left edge of the Bay has the main traffic around the city and the major source of PAHs is from combustion processes and estuarine inputs, leading to medium values of PAHs in the sediments; the right edge of the Bay has much lesser anthropogenic activities leading to lower values of PAHs in sediments. The distribution of individual PAHs in sediments varies widely depending on their structure and molecular weight; the 4-6 ring aromatics predominate in polluted sediments due to their higher persistence. The isomer ratio does not allow any clear identification of the PAHs origin. Environmental evaluation according to Dutch guidelines and consensus sediment quality guidelines based on ecotoxicological data leads to the same conclusion, sediments in the Santander Bay show a very different environmental quality depending on the spatial position from heavily polluted/medium effects to non

  10. Later life swimming performance and persistent heart damage following subteratogenic PAH mixture exposure in the Atlantic killifish (Fundulus heteroclitus).

    Science.gov (United States)

    Brown, Daniel R; Thompson, Jasmine; Chernick, Melissa; Hinton, David E; Di Giulio, Richard T

    2017-12-01

    High-level, acute exposures to individual polycyclic aromatic hydrocarbons (PAHs) and complex PAH mixtures result in cardiac abnormalities in developing fish embryos. Whereas acute PAH exposures can be developmentally lethal, little is known about the later life consequences of early life, lower level PAH exposures in survivors. A population of PAH-adapted Fundulus heteroclitus from the PAH-contaminated Superfund site, Atlantic Wood Industries, Elizabeth River, Portsmouth, Virginia, United States, is highly resistant to acute PAH cardiac teratogenicity. We sought to determine and characterize long-term swimming performance and cardiac histological alterations of a subteratogenic PAH mixture exposure in both reference killifish and PAH-adapted Atlantic Wood killifish embryos. Killifish from a relatively uncontaminated reference site, King's Creek, Virginia, United States, and Atlantic Wood killifish were treated with dilutions of Elizabeth River sediment extract at 24 h post fertilization (hpf). Two proven subteratogenic dilutions, 0.1 and 1.0% Elizabeth River sediment extract (total PAH 5.04 and 50.4 µg/L, respectively), were used for embryo exposures. Then, at 5-mo post hatching, killifish were subjected to a swim performance test. A separate subset of these individuals was processed for cardiac histological analysis. Unexposed King's Creek killifish significantly outperformed the unexposed Atlantic Wood killifish in swimming performance as measured by Ucrit (i.e., critical swimming speed). However, King's Creek killifish exposed to Elizabeth River sediment extract (both 0.1 and 1.0%) showed significant declines in Ucrit. Histological analysis revealed the presence of blood in the pericardium of King's Creek killifish. Although Atlantic Wood killifish showed baseline performance deficits relative to King's Creek killifish, their pericardial cavities were nearly free of blood and atrial and ventricular alterations. These findings may explain, in part, the

  11. MEASUREMENT OF TOTAL SITE MERCURY EMISSIONS FROM A CHLOR-ALKALI PLANT USING OPEN-PATH UV-DOAS

    Science.gov (United States)

    In December 2003, the EPA promulgated the National Emission Standard for Hazardous Air Pollutants for mercury cell chlor-alkali plants. In February 2004, the Natural Resources Defense Council filed petitions on the final rule in U.S. district court citing, among other issues, th...

  12. Comparison of techniques for estimating PAH bioavailability: Uptake in Eisenia fetida, passive samplers and leaching using various solvents and additives

    Energy Technology Data Exchange (ETDEWEB)

    Bergknut, Magnus [Department of Chemistry, Environmental Chemistry, Umeaa University, SE-90187 Umeaa (Sweden)]. E-mail: magnus.bergknut@chem.umu.se; Sehlin, Emma [Department of Chemistry, Environmental Chemistry, Umeaa University, SE-90187 Umeaa (Sweden); Lundstedt, Staffan [Department of Chemistry, Environmental Chemistry, Umeaa University, SE-90187 Umeaa (Sweden); Andersson, Patrik L. [Department of Chemistry, Environmental Chemistry, Umeaa University, SE-90187 Umeaa (Sweden); Haglund, Peter [Department of Chemistry, Environmental Chemistry, Umeaa University, SE-90187 Umeaa (Sweden); Tysklind, Mats [Department of Chemistry, Environmental Chemistry, Umeaa University, SE-90187 Umeaa (Sweden)

    2007-01-15

    The aim of this study was to evaluate different techniques for assessing the availability of polycyclic aromatic hydrocarbons (PAHs) in soil. This was done by comparing the amounts (total and relative) taken up by the earthworm Eisenia fetida with the amounts extracted by solid-phase microextraction (SPME), semi-permeable membrane devices (SPMDs), leaching with various solvent mixtures, leaching using additives, and sequential leaching. Bioconcentration factors of PAHs in the earthworms based on equilibrium partitioning theory resulted in poor correlations to observed values. This was most notable for PAHs with high concentrations in the studied soil. Evaluation by principal component analysis (PCA) showed distinct differences between the evaluated techniques and, generally, there were larger proportions of carcinogenic PAHs (4-6 fused rings) in the earthworms. These results suggest that it may be difficult to develop a chemical method that is capable of mimicking biological uptake, and thus estimating the bioavailability of PAHs. - The total and relative amounts of PAHs extracted by abiotic techniques for assessing the bioavailability of PAHs was found to differ from the amounts taken up by Eisenia fetida.

  13. Comparison of techniques for estimating PAH bioavailability: Uptake in Eisenia fetida, passive samplers and leaching using various solvents and additives

    International Nuclear Information System (INIS)

    Bergknut, Magnus; Sehlin, Emma; Lundstedt, Staffan; Andersson, Patrik L.; Haglund, Peter; Tysklind, Mats

    2007-01-01

    The aim of this study was to evaluate different techniques for assessing the availability of polycyclic aromatic hydrocarbons (PAHs) in soil. This was done by comparing the amounts (total and relative) taken up by the earthworm Eisenia fetida with the amounts extracted by solid-phase microextraction (SPME), semi-permeable membrane devices (SPMDs), leaching with various solvent mixtures, leaching using additives, and sequential leaching. Bioconcentration factors of PAHs in the earthworms based on equilibrium partitioning theory resulted in poor correlations to observed values. This was most notable for PAHs with high concentrations in the studied soil. Evaluation by principal component analysis (PCA) showed distinct differences between the evaluated techniques and, generally, there were larger proportions of carcinogenic PAHs (4-6 fused rings) in the earthworms. These results suggest that it may be difficult to develop a chemical method that is capable of mimicking biological uptake, and thus estimating the bioavailability of PAHs. - The total and relative amounts of PAHs extracted by abiotic techniques for assessing the bioavailability of PAHs was found to differ from the amounts taken up by Eisenia fetida

  14. Distribution and health risks of polycyclic aromatic hydrocarbons (PAHs) in smoke aerosols from burning of selected garden wastes

    International Nuclear Information System (INIS)

    Hui, Tay Joo; Seng, Tan Hock; Mohd Radzi Abas; Norhayati Mohd Tahir

    2008-01-01

    A study has been carried out to characterize polycyclic aromatic hydrocarbons emitted from the burning of five types of typical garden wastes viz, Bachang, Mango, Jackfruit, Jambu Air litter fall and a type of Grass. The samples were burned to the ember and respective smoke aerosols emitted during the burning period were sampled using high volume filtration on a pre-cleaned glass fibre filters. Polycyclic aromatic hydrocarbons (PAHs) were extracted using dichloromethane-methanol (3:1) as solvent and the extracts fractionated on silica-alumina column. Detection and quantification of PAHs compounds were carried out using GC-MS. Results indicated that burning resulted in the formation of significant amount of PAHs compounds in all samples; total PAHs compounds emitted were in the range of 0.41 to 42.2 μg/ m 3 . The major PAHs compound exhibited in all smoke samples were three to four rings PAHs (example fluoranthene and pyrene) with lesser amount of five to six rings (example benzo(a)pyrene and benzo(g,h,i) perylene) and two rings PAHs (example acenaphthylene). The BaP equivalency results showed that the potential health risk from these garden wastes smoke were very significant; total BaP equivalency values were in the range of 5.60 E+04 pg/ m 3 - 4.98 E+06 pg/ m 3 with Jambu Air smoke exhibited the highest potential health risk. (author)

  15. Spatial variation of PAHs and PCBs in coastal air, seawater, and sediments in a heavily industrialized region.

    Science.gov (United States)

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

    2017-05-01

    Concurrent coastal seawater (n = 22), sediment (n = 22), and atmospheric samples (n = 10) were collected in the Aliaga industrial region, Turkey, to explore the spatial variation, sources, and air-seawater exchange of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). Seawater Σ 16 PAH concentrations (particle + dissolved) ranged between 5107 and 294,624 pg L -1 , while Σ 41 PCB concentrations were in the range of 880-50,829 pg L -1 . Levels in sediments were highly variable ranging between 35.5-49,682 and 2.7-2450 μg kg -1 in dry weight for Σ 16 PAHs and Σ 41 PCBs, respectively. Atmospheric concentrations varied between 1791-274,974 and 104-20,083 pg m -3 for Σ 16 PAHs and Σ 41 PCBs, respectively. Sediment organic matter (OM) content and levels of Σ 16 PAHs and Σ 41 PCBs correlated weakly (r 2  = 0.19-0.23, p seawater, and sediment and factor analysis on the sediment levels pointed out that the major sources in the region are steel plants, petroleum refinery, petrochemical complex, ship breaking, loading/unloading activities at the ports, vehicular emissions, and fossil fuel combustion emissions. The direction of the air-seawater exchange was also explored by estimating seawater fugacity fractions of PAHs and PCBs. For PAHs, the number of cases implying deposition (43.0%) and volatilization (39.5%) was similar, while for PCBs, the number of cases implying volatilization (60.4%) was much higher compared to deposition (21.6%). Fugacity fractions were generally seawater and sediment levels were measured, implying that atmospheric deposition is an important mechanism affecting seawater and sediment PAH and PCB levels.

  16. PCB and PAH release from power stations and waste incineration processes in the UK

    Energy Technology Data Exchange (ETDEWEB)

    Dyke, Patrick H. [PD Consulting, Magdalen, Brobury, HR3 6DX (United Kingdom); Foan, Colin [The Environment Agency, National Centre for Risk Analysis and Options Appraisal, Kings Meadow House, Kings Meadow Road, Reading, (United Kingdom); Fiedler, Heidelore [United Nations Environment Programme (UNEP) Chemicals, 11-13, chemin des Anemones, CH-1219, Chatelaine (Switzerland)

    2003-01-01

    This study focused on emissions of polychlorinated biphenyls (PCB) and polycyclic aromatic hydrocarbons (PAH) from incineration and power generation processes. Increased concern over human exposure to both classes of compounds has meant that environmental regulators need to assess the contribution made by emissions from regulated processes to human exposure. In the first part of an assessment in the UK we reviewed literature data on emissions of PCB, focusing on the dioxin-like PCB assigned toxic equivalency factors by the World Health Organization, and PAH. The literature study was supplemented by a series of plant tests to gather initial real plant data. Literature data were limited and the lack of standard protocols for measurement and reporting of both PCB and PAH meant that few data sets were comparable. Levels of dioxin-like PCB reported in the literature and measured in UK plant tests showed that well-controlled modern combustion plants with comprehensive pollution controls gave low emissions, typically about 5-10% of the toxic equivalent of the emissions of polychlorinated dibenzodioxins and dibenzofurans at the same plants and below the widely used standard of 0.1 ng TEQ/N m{sup 3}. (Author)

  17. Occurrence of nitro- and oxy-PAHs in agricultural soils in eastern China and excess lifetime cancer risks from human exposure through soil ingestion.

    Science.gov (United States)

    Sun, Zhe; Zhu, Ying; Zhuo, Shaojie; Liu, Weiping; Zeng, Eddy Y; Wang, Xilong; Xing, Baoshan; Tao, Shu

    2017-11-01

    The quality of agricultural soil is vital to human health, however soil contamination is a severe problem in China. Polycyclic aromatic hydrocarbons (PAHs) have been found to be among the major soil contaminants in China. PAH derivatives could be more toxic but their measurements in soils are extremely limited. This study reports levels, spatial distributions and compositions of 11 nitrated (nPAHs) and 4 oxygenated PAHs (oPAHs) in agricultural soils covering 26 provinces in eastern China to fill the data gap. The excess lifetime cancer risk (ELCR) from the exposure to them in addition to 21 parent PAHs (pPAHs) via soil ingestion has been estimated. The mean concentration of ∑nPAHs and ∑oPAHs in agricultural soils is 50±45μg/kg and 9±8μg/kg respectively. Both ∑nPAHs and ∑oPAHs follow a similar spatial distribution pattern with elevated concentrations found in Liaoning, Shanxi, Henan and Guizhou. However if taking account of pPAHs, the high ELCR by soil ingestion is estimated for Shanxi, Zhejiang, Liaoning, Jiangsu and Hubei. The maximum ELCR is estimated at ca.10 -5 by both deterministic and probabilistic studies with moderate toxic equivalent factors (TEFs). If maximum TEFs available are applied, there is a 0.2% probability that the ELCR will exceed 10 -4 in the areas covered. There is a great chance to underestimate the ELCR via soil ingestion for some regions if only the 16 priority PAHs in agricultural soils are considered. The early life exposure and burden are considered extremely important to ELCR. Emission sources are qualitatively predicted and for areas with higher ELCR such as Shanxi and Liaoning, new loadings of PAHs and derivatives are identified. This is the first large scale study on nPAHs and oPAHs contamination levels in agricultural soils in China. The risk assessment based on this underpins the policy making and is valuable for both scientists and policy makers. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Properties of polycyclic aromatic hydrocarbons in the northwest photon dominated region of NGC 7023. II. Traditional PAH analysis using k-means as a visualization tool

    Energy Technology Data Exchange (ETDEWEB)

    Boersma, C.; Bregman, J.; Allamandola, L. J., E-mail: Christiaan.Boersma@nasa.gov [NASA Ames Research Center, MS 245-6, Moffett Field, CA 94035-0001 (United States)

    2014-11-10

    Polycyclic aromatic hydrocarbon (PAH) emission in the Spitzer-IRS spectral map of the northwest photon dominated region (PDR) in NGC 7023 is analyzed using the 'traditional' approach in which the PAH bands and plateaus between 5.2-19.5 μm are isolated by subtracting the underlying continuum and removing H{sub 2} emission lines. The spectra are organized into seven spectroscopic bins by using k-means clustering. Each cluster corresponds to, and reveals, a morphological zone within NGC 7023. The zones self-organize parallel to the well-defined PDR front that coincides with an increase in intensity of the H{sub 2} emission lines. PAH band profiles and integrated strengths are measured, classified, and mapped. The morphological zones revealed by the k-means clustering provides deeper insight into the conditions that drive variations in band strength ratios and evolution of the PAH population that otherwise would be lost. For example, certain band-band relations are bifurcated, revealing two limiting cases; one associated with the PDR, the other with the diffuse medium. Traditionally, PAH band strength ratios are used to gain insight into the properties of the emitting PAH population, i.e., charge, size, structure, and composition. Insights inferred from this work are compared and contrasted to those from Boersma et al. (first paper in this series), where the PAH emission in NGC 7023 is decomposed exclusively using the PAH spectra and tools made available through the NASA Ames PAH IR Spectroscopic Database.

  19. Relating Bioavailability Parameters to the Sorbent Characteristics of PAH Polluted Soils

    DEFF Research Database (Denmark)

    Bartolome, N.; Hilber, I.; Schulin, R.

    2015-01-01

    Regulation of Hydrophobic Organic Contaminants (HOC) such as polycyclic aromatic hydrocarbons (PAHs) in soil is still based on total concentrations. However, many studies have demonstrated that not all of a pollutant’s content in soil is equally available to organisms (Reichenberg & Mayer 2006...... to several sorbent characteristics including organic and black carbon content. The results will provide a better understanding of bioavailability of PAHs in soils. Moreover, the outcomes will be discussed regarding to the potential application of chemical proxies in soil pollution risk assessment......). Over the last decade, intensive effort has been made to incorporate bioavailability into risk assessment (Cachada et al. 2014). Here, we compare total concentrations of PAH with two bioavailability parameters in 30 different soil samples from the archive of the standardized National and Zurich Cantonal...

  20. Measuring the Total-Factor Carbon Emission Performance of Industrial Land Use in China Based on the Global Directional Distance Function and Non-Radial Luenberger Productivity Index

    Directory of Open Access Journals (Sweden)

    Wei Wang

    2016-04-01

    Full Text Available Industry is a major contributor to carbon emissions in China, and industrial land is an important input to industrial production. Therefore, a detailed analysis of the carbon emission performance of industrial land use is necessary for making reasonable carbon reduction policies that promote the sustainable use of industrial land. This paper aims to analyze the dynamic changes in the total-factor carbon emission performance of industrial land use (TCPIL in China by applying a global directional distance function (DDF and non-radial Luenberger productivity index. The empirical results show that the eastern region enjoys better TCPIL than the central and western regions, but the regional gaps in TCPIL are narrowing. The growth in NLCPILs (non-radial Luenberger carbon emission performance of industrial land use in the eastern and central regions is mainly driven by technological progress, whereas efficiency improvements contribute more to the growth of NLCPIL in the western region. The provinces in the eastern region have the most innovative and environmentally-friendly production technologies. The results of the analysis of the influencing factors show implications for improving the NLCPIL, including more investment in industrial research and development (R&D, the implementation of carbon emission reduction policies, reduction in the use of fossil energy, especially coal, in the process of industrial production, actively learning about foreign advanced technology, properly solving the problem of surplus labor in industry and the expansion of industrial development.

  1. Bioremediation of soils and sediments containing PAHs and PCP using Daramend trademark

    International Nuclear Information System (INIS)

    Seech, A.; Burwell, S.; Marvan, I.

    1994-01-01

    A full-scale demonstration of Grace Dearborn's Daramend trademark for bioremediation of soil containing chlorinated phenols, PAHs and petroleum hydrocarbons is being conducted at an industrial wood treatment site in Ontario. A pilot-scale demonstration of Daramend for the clean-up of sediments contaminated with PAHs was also conducted. The full-scale demonstration, which includes bioremediation of approximately 4,500 m 3 of soil, was initiated at a wood preserving facility in Ontario, in the summer of 1993. The soil contains chlorinated phenols, PAHs and total petroleum hydrocarbons at concentrations of up to 700, 1,400 and 6,300 mg/kg respectively. Full-scale bioremediation at this site employs the same Daramend protocols and organic amendment treatments that were used at the pilot-scale phase where the PAH, total petroleum hydrocarbon, and pentachlorophenol concentrations were reduced to below the Canadian clean-up guidelines for industrial soils. In addition, the toxicity of the soil to earthworms was eliminated while the rate of seed germination was increased to that of an agricultural soil during the pilot scale demonstration phase. The ex-situ portion of the full-scale demonstration is currently being audited by the EPA under the SITE program. This paper will focus on the ex-situ work. The pilot-scale demonstration of sediment remediation consisted of ex-situ bioremediation of approximately 90 tonnes of PAH-contaminated sediment in a confined treatment area

  2. Biological treatment of PAH-contaminated sediments in a Sequencing Batch Reactor

    International Nuclear Information System (INIS)

    Chiavola, Agostina; Baciocchi, Renato; Gavasci, Renato

    2010-01-01

    The technical feasibility of a sequential batch process for the biological treatment of sediments contaminated by polycyclic aromatic hydrocarbons (PAHs) was evaluated through an experimental study. A bench-scale Sediment Slurry Sequencing Batch Reactor (SS-SBR) was fed with river sediments contaminated by a PAH mixture made by fluorene, anthracene, pyrene and crysene. The process performance was evaluated under different operating conditions, obtained by modifying the influent organic load, the feed composition and the hydraulic residence time. Measurements of the Oxygen Uptake Rates (OURs) provided useful insights on the biological kinetics occurring in the SS-SBR, suggesting the minimum applied cycle time-length of 7 days could be eventually halved, as also confirmed by the trend observed in the volatile solid and total organic carbon data. The removal efficiencies gradually improved during the SS-SBR operation, achieving at the end of the study rather constant removal rates above 80% for both 3-rings PAHs (fluorene and anthracene) and 4-ring PAHs (pyrene and crysene) for an inlet total PAH concentration of 70 mg/kg as dry weight (dw).

  3. Phyto remediation of PAH contaminated soil

    International Nuclear Information System (INIS)

    Petruzzelli, G.; Pedron, F.; Barbafieri, M.; Cervelli, St.; Vigna Guidi, G.

    2005-01-01

    Phyto-remediation may enhance degradation of organic compounds promoting an adequate substrate for microbial growth. The aim of this work was to evaluate the efficiency of two plant species, Lupinus albus and Zea mais, in the bio-remediation of a PAH contaminated soil. This soil has been collected in a contaminated industrial area in Italy characterized by PAH concentrations up to 16000 mg/Kg. Microcosms experiments were carried out by planting Lupinus albus and Zea mais in the polluted soil; controls without plants were run separately. Growing period lasted by three months. Plants favoured PAH biodegradation by percentages of 32% with Lupinus albus and 22% with Zea mais, with respect to non vegetated microcosms. (authors)

  4. Non-relativistic Free–Free Emission due to the n -distribution of Electrons—Radiative Cooling and Thermally Averaged and Total Gaunt Factors

    Energy Technology Data Exchange (ETDEWEB)

    De Avillez, Miguel A. [Department of Mathematics, University of Évora, R. Romão Ramalho 59, 7000 Évora (Portugal); Breitschwerdt, Dieter, E-mail: mavillez@galaxy.lca.uevora.pt [Zentrum für Astronomie und Astrophysik, Technische Universität Berlin, Hardenbergstrasse 36, D-10623 Berlin (Germany)

    2017-09-01

    Tracking the thermal evolution of plasmas, characterized by an n -distribution, using numerical simulations, requires the determination of the emission spectra and of the radiative losses due to free–free emission from the corresponding temperature-averaged and total Gaunt factors. Detailed calculations of the latter are presented and associated with n -distributed electrons with the parameter n ranging from 1 (corresponding to the Maxwell–Boltzmann distribution) to 100. The temperature-averaged and total Gaunt factors with decreasing n tend toward those obtained with the Maxwell–Boltzmann distribution. Radiative losses due to free–free emission in a plasma evolving under collisional ionization equilibrium conditions and composed by H, He, C, N, O, Ne, Mg, Si, S, and Fe ions, are presented. These losses decrease with a decrease in the parameter n , reaching a minimum when n  = 1, and thus converge with the loss of thermal plasma. Tables of the thermal-averaged and total Gaunt factors calculated for n -distributions, and a wide range of electron and photon energies, are presented.

  5. Non-relativistic Free–Free Emission due to the n -distribution of Electrons—Radiative Cooling and Thermally Averaged and Total Gaunt Factors

    International Nuclear Information System (INIS)

    De Avillez, Miguel A.; Breitschwerdt, Dieter

    2017-01-01

    Tracking the thermal evolution of plasmas, characterized by an n -distribution, using numerical simulations, requires the determination of the emission spectra and of the radiative losses due to free–free emission from the corresponding temperature-averaged and total Gaunt factors. Detailed calculations of the latter are presented and associated with n -distributed electrons with the parameter n ranging from 1 (corresponding to the Maxwell–Boltzmann distribution) to 100. The temperature-averaged and total Gaunt factors with decreasing n tend toward those obtained with the Maxwell–Boltzmann distribution. Radiative losses due to free–free emission in a plasma evolving under collisional ionization equilibrium conditions and composed by H, He, C, N, O, Ne, Mg, Si, S, and Fe ions, are presented. These losses decrease with a decrease in the parameter n , reaching a minimum when n  = 1, and thus converge with the loss of thermal plasma. Tables of the thermal-averaged and total Gaunt factors calculated for n -distributions, and a wide range of electron and photon energies, are presented.

  6. Co-formation and co-release of genotoxic PAHs, alkyl-PAHs and soot nanoparticles from gasoline direct injection vehicles

    Science.gov (United States)

    Muñoz, Maria; Haag, Regula; Honegger, Peter; Zeyer, Kerstin; Mohn, Joachim; Comte, Pierre; Czerwinski, Jan; Heeb, Norbert V.

    2018-04-01

    Gasoline direct injection (GDI) vehicles quickly replace traditional port-fuel injection (PFI) vehicles in Europe reaching about 50 million vehicles on roads in 2020. GDI vehicles release large numbers of soot nanoparticles similar to conventional diesel vehicles without particle filters. These exhausts will increasingly affect air quality in European cities. We hypothesized that such particles are released together with polycyclic aromatic hydrocarbons (PAHs) formed under the same combustion conditions. Emission data of a fleet of 7 GDI vehicles (1.2-1.8 L) including Euro-3,-4,-5 and -6 technologies revealed substantial particle emissions on average of 2.5 × 1012 particles km-1 in the cold worldwide harmonized light vehicle test cycle (cWLTC), the future European legislative driving cycle. Particle emissions increased 2-3 orders of magnitude during acceleration like CO, indicating that transient driving produces fuel-rich conditions with intense particle formation. For comparison, an Euro-5 diesel vehicle (1.6 L) equipped with a particle filter released 3.9 × 1010 particles km-1 (cWLTC), clearly within the Euro-5/6 limit value of 6.0 × 1011 particles km-1 and 64-fold below the GDI fleet average. PAH and alkyl-PAH emissions of the GDI vehicles also exceeded those of the diesel vehicle. Mean GDI emissions of 2-, 3-, 4-, 5- and 6-ring PAHs in the cWLTC were 240, 44, 5.8, 0.5 and 0.4 μg km-1, those of the diesel vehicle were only 8.8, 7.1, 8.6, 0.02 and 0.02 μg km-1, respectively. Thus mean PAH emissions of the GDI fleet were 2 orders of magnitude higher than the bench mark diesel vehicle. A comparison of the toxicity equivalent concentrations (TEQ) in the cWLTC of the GDI fleet and the diesel vehicle revealed that GDI vehicles released 200-1700 ng TEQ m-3 genotoxic PAHs, being 6-40 times higher than the diesel vehicle with 45 ng TEQ km-1. The co-release of genotoxic PAHs adsorbed on numerous soot nanoparticles is critical due to the Trojan horse effect

  7. Impact of using fishing boat fuel with high poly aromatic content on the emission of polycyclic aromatic hydrocarbons from the diesel engine

    Science.gov (United States)

    Lin, Yuan-Chung; Lee, Wen-Jhy; Li, Hsing-Wang; Chen, Chung-Ban; Fang, Guor-Cheng; Tsai, Perng-Jy

    Because of the fishery subsidy policy, the fishing boat fuel oil (FBFO) exemption from commodity taxes, business taxes and air pollution control fees, resulted in the price of FBFO was ˜50% lower than premium diesel fuel (PDF) in Taiwan. It is estimated that ˜650,000 kL FBFO was illegally used by traveling diesel-vehicles (TDVs) with a heavy-duty diesel engine (HDDE), which accounted for ˜16.3% of the total diesel fuel consumed by TDVs. In this study, sulfur, poly aromatic and total-aromatic contents in both FBFO and PDF were measured and compared. Exhaust emissions of polycyclic aromatic hydrocarbons (PAHs) and their carcinogenic potencies (BaP eq) from a HDDE under transient cycle testing for both FBFO and PDF were compared and discussed. Finally, the impact caused by the illegal use of FBFO on the air quality was examined. Results show that the mean sulfur-, poly aromatic and aromatic-contents in FBFO were 43.0, 3.89 and 1.04 times higher than that of PDF, respectively. Emission factors of total-PAHs and total-BaP eq obtained by utilizing FBFO were 51.5 and 0.235 mg L -1-Fuel, which were 3.41 and 5.82 times in magnitude higher than obtained by PDF, respectively. The estimated annual emissions of total-PAHs and total-BaP eq to the ambient environment due to the illegally used FBFO were 23.6 and 0.126 metric tons, respectively, which resulted in a 17.9% and a 25.0% increment of annual emissions from all mobile sources, respectively. These results indicated that the FBFO used illegally by TDVs had a significant impact on PAH emissions to the ambient environment.

  8. Modeling personal particle-bound polycyclic aromatic hydrocarbon (pb-pah) exposure in human subjects in Southern California.

    Science.gov (United States)

    Wu, Jun; Tjoa, Thomas; Li, Lianfa; Jaimes, Guillermo; Delfino, Ralph J

    2012-07-11

    Exposure to polycyclic aromatic hydrocarbon (PAH) has been linked to various adverse health outcomes. Personal PAH exposures are usually measured by personal monitoring or biomarkers, which are costly and impractical for a large population. Modeling is a cost-effective alternative to characterize personal PAH exposure although challenges exist because the PAH exposure can be highly variable between locations and individuals in non-occupational settings. In this study we developed models to estimate personal inhalation exposures to particle-bound PAH (PB-PAH) using data from global positioning system (GPS) time-activity tracking data, traffic activity, and questionnaire information. We conducted real-time (1-min interval) personal PB-PAH exposure sampling coupled with GPS tracking in 28 non-smoking women for one to three sessions and one to nine days each session from August 2009 to November 2010 in Los Angeles and Orange Counties, California. Each subject filled out a baseline questionnaire and environmental and behavior questionnaires on their typical activities in the previous three months. A validated model was used to classify major time-activity patterns (indoor, in-vehicle, and other) based on the raw GPS data. Multiple-linear regression and mixed effect models were developed to estimate averaged daily and subject-level PB-PAH exposures. The covariates we examined included day of week and time of day, GPS-based time-activity and GPS speed, traffic- and roadway-related parameters, meteorological variables (i.e. temperature, wind speed, relative humidity), and socio-demographic variables and occupational exposures from the questionnaire. We measured personal PB-PAH exposures for 180 days with more than 6 h of valid data on each day. The adjusted R2 of the model was 0.58 for personal daily exposures, 0.61 for subject-level personal exposures, and 0.75 for subject-level micro-environmental exposures. The amount of time in vehicle (averaging 4.5% of total

  9. [Mutation analysis of the PAH gene in children with phenylketonuria from the Qinghai area of China].

    Science.gov (United States)

    He, Jiang; Wang, Hui-Zhen; Xu, Fa-Liang; Yang, Xi; Wang, Rui; Zou, Hong-Yun; Yu, Wu-Zhong

    2015-11-01

    To study the mutation characteristics of the phenylalanine hydroxylase (PAH) gene in children with phenylketonuria (PKU) from the Qinghai area of China, in order to provide basic information for genetic counseling and prenatal diagnosis. Mutations of the PAH gene were detected in the promoter and exons 1-13 and their flanking intronic sequences of PAH gene by PCR and DNA sequencing in 49 children with PKU and their parents from the Qinghai area of China. A total of 30 different mutations were detected in 80 out of 98 mutant alleles (82%), including 19 missense (63%), 5 nonsense (17%), 3 splice-site (10%) and 3 deletions (10%). Most mutations were detected in exons 3, 6, 7, 11 and intron 4 of PAH gene. The most frequent mutations were p.R243Q (19%), IVS4-1G>A (9%), p.Y356X (7%) and p.EX6-96A>G(5%). Two novel mutations p.N93fsX5 (c.279-282delCATC) and p.G171E (c.512G>A) were found. p.H64fsX9(c.190delC) was documented for the second time in Chinese PAH gene. The mutation spectrum of the gene PAH in the Qinghai population was similar to that in other populations in North China while significantly different from that in the populations from some provinces in southern China, Japan and Europe. The mutations of PAH gene in the Qinghai area of China demonstrate a unique diversity, complexity and specificity.

  10. Removal of PAHs from contaminated clayey soil by means of electro-osmosis

    KAUST Repository

    Lima, Ana T.

    2011-06-01

    The removal of polycyclic aromatic hydrocarbons (PAHs) from clayey soils is an intricate task. The low porosity of compacted clayey soil hinders bacterial activity and makes convective removal by hydraulic flow impossible. Electro-osmosis is a process that has been used for the mobilization and cleanup of contaminants in clayey soils with varying successes. The present study focuses on the remediation of a contaminated peaty clay soil, located in Olst - the Netherlands, by means of electro-osmosis. The soil was originally contaminated by an asphalt production plant, active from 1903 to 1983, and presents high levels of all 16 priority PAHs indicated by the US Environmental Protection Agency (EPA). Such a long contact times of PAH with the soil (≥100 years) presents a unique study material with well established solid/liquid contaminant partitioning equilibrium, preferable to artificially spiked soil. A batch of 6 electro-osmosis laboratory experiments was carried out to study the removal of 16 PAHs through electro-osmosis. In these experiments, water and a surfactant (Tween 80) were used to enhance the PAH desorption. The electro-osmotic conductivities ranged from 2.88 × 10-10 to a substantial 1.19 × 10-7 m2 V-1 s -1 when applying a current density of 0.005-0.127 A m-2. Electro-osmosis was expected to occur towards the cathode, because of natural soil characteristics (negative zeta potential), but presented scattered directions. The use of reference electrodes proved to be very effective to the prediction of the flow direction. Finally, the addition of Tween 80 as a surfactant enhanced PAH removal up to 30% of the total PAH content of the soil in 9 days. © 2011 Elsevier B.V.

  11. Chemical analysis and genotoxicity of high molecular mass PAH in sediment samples and biota

    International Nuclear Information System (INIS)

    McCarry, B.E.; Marvin, C.H.; Smith, R.W.; Bryant, D.W.

    1995-01-01

    A normal phase liquid chromatography (NPLC) method was used to fractionate the organic extracts of prepared from coal tar-contaminated sediments from hamilton Harbor in Ontario and from Sydney Harbor in Nova Scotia into molecular mass classes. Each PAH fraction up to 302 amu was analyzed by GC-MS and fractions containing PAH with molecular masses greater than 302 amu were analyzed by atmospheric pressure chemical ionization (APCI) LC-MS.Each fraction was also subjected to Ames bioassays using a TA100-like strain of Salmonella typhimurium (YG1025 + S9). The 300/302 amu, 326/328 and 350/352 amu PAH fractions accounted for 25% of the total genotoxic response of the extract; these PAH constitute a substantial genotoxic burden. A number of 300, 302, 326, 350, 374 and 400 amu PAH were identified using APCI LC-MS and comparison with authentic standards. The non-polar aromatic extracts of bottom sediments, suspended sediments and zebra mussels from Hamilton Harbor were also examined by GC-MS, APCI LC-MS and genotoxicity bioassays. The profiles of the priority and high mass PAH in these samples were identical showing that all PAH up to and exceeding 400 amu were readily bioavailable to biota such as Zebra mussels. In addition, the pseudo faeces of the Zebra mussels and amphipod detritivores which fed on the pseudo faeces had chemical profiles identical to the Zebra mussels. Since many sport fish prize amphipods as food, this observation demonstrates a pathway for organic contaminants adsorbed to suspended sediments to enter the food chain of non-bottom-feeding fish in areas infested by Zebra mussels

  12. Micellar Enhanced Ultrafiltration for the Removal of Polycyclic Aromatic Hydrocarbons (PAHs Mixtures in Underground Contaminated Water in Oman

    Directory of Open Access Journals (Sweden)

    Mohamed Aoudia

    2011-12-01

    Full Text Available In an attempt to analyze polycyclic aromatic hydrocarbons (PAHs in diesel contaminated underground water in Oman (Rustaq, Gas chromatography-Mass spectrometry was first used to determine the different concentrations in a standard mixture containing 16 PAHs. Retention time and calibration curves were obtained for all aromatic compounds and were used to identify a given analyte as well as its concentration in the contaminated underground water. Micellar enhanced ultrafiltration (MEUF was then used to treat standard aqueous solution of PAHs at low concentration (~ 1 ppb using an edible nonionic surfactant (Tween 80. The totality of the mixture components was completely rejected. Within the experimental detection limit (± 0.01 ppb, the residual PAH concentrations were less than 0.01 ppb in accord with the allowed concentrations in drinking water. Likewise, excellent rejections of PAHs in MEUF treatment of diesel contaminated underground water at an Omani site (Rustaq were observed. The concentration of PAHs was reduced to less than 0.01 ppb, the accepted limit for the most toxic member of the PAH group (benzo(apyrene.

  13. Ambient concentrations and personal exposure to polycyclic aromatic hydrocarbons (PAH) in an urban community with mixed sources of air pollution

    Science.gov (United States)

    ZHU, XIANLEI; FAN, ZHIHUA (TINA); WU, XIANGMEI; JUNG, KYUNG HWA; OHMAN-STRICKLAND, PAMELA; BONANNO, LINDA J.; LIOY, PAUL J.

    2014-01-01

    Assessment of the health risks resulting from exposure to ambient polycyclic aromatic hydrocarbons (PAH) is limited by a lack of environmental exposure data among the general population. This study characterized personal exposure and ambient concentrations of PAH in the Village of Waterfront South (WFS), an urban community with many mixed sources of air toxics in Camden, New Jersey, and CopeWood/Davis Streets (CDS), an urban reference area located ~1 mile east of WFS. A total of 54 and 53 participants were recruited from non-smoking households in WFS and CDS, respectively. In all, 24-h personal and ambient air samples were collected simultaneously in both areas on weekdays and weekends during summer and winter. The ambient PAH concentrations in WFS were either significantly higher than or comparable to those in CDS, indicating the significant impact of local sources on PAH pollution in WFS. Analysis of diagnostic ratios and correlation suggested that diesel truck traffic, municipal waste combustion and industrial combustion were the major sources in WFS. In such an area, ambient air pollution contributed significantly to personal PAH exposure, explaining 44–96% of variability in personal concentrations. This study provides valuable data for examining the impact of local ambient PAH pollution on personal exposure and therefore potential health risks associated with environmental PAH pollution. PMID:21364704

  14. Effect of water flux and sediment discharge of the Yangtze River on PAHs sedimentation in the estuary.

    Science.gov (United States)

    Li, Rufeng; Feng, Chenghong; Wang, Dongxin; He, Maozhi; Hu, Lijuan; Shen, Zhenyao

    2016-12-01

    Historical distribution characteristics of polycyclic aromatic hydrocarbons (PAHs) and their carriers (i.e., organic matter and mineral particles) in the sediment cores of the Yangtze Estuary were investigated, with emphasis laid on the role of the Yangtze River. Grain size component of sediments (clay, silt, and sand) and organic carbon (black carbon and total organic carbon) in the sediment cores were markedly affected by water flux and sediment discharge of the Yangtze River. Qualitative and quantitative analysis results showed that sands and black carbon acted as the main carriers of PAHs. The sedimentation of two-ring to three-ring PAHs in the estuary had significant correlations with water flux and sediment discharge of the Yangtze River. The relative lower level of the four-ring and five-ring to six-ring PAHs concentrations appeared around the year 2003 and remained for the following several years. This time period accorded well with the water impoundment time of the Three Gorges Reservoir. The decreased level of two-ring to three-ring PAHs occurred in the year 1994, and the peak points around the year 2009 indicated that PAHs sedimentation in the estuary also had close relationship to severe drought and flood in the catchments. The findings presented in this paper could provide references for assessing the impacts of water flux and sediment discharge on the historical deposition of PAHs and their carriers in the Yangtze Estuary.

  15. Aromatization of oils from coal-tyre cothermolysis. Part 2. PAH content study as a function of the process variables

    Energy Technology Data Exchange (ETDEWEB)

    Mastral, A.M.; Callen, S.; Garcia, T.; Navarro, M.V. [Department of Energy and Environmental, Instituto de Carboquimica CSIC, P.O. Box 589, C/Maria de Luna, 12, 50015, Zaragoza (Spain)

    2000-10-01

    In this work, the PAH content in the oils obtained from hydro-cothermolysis have been analysed. The influence of the process variables (H{sub 2} pressure, 1 and 10 MPa, different feed materials: coal, tyre and a blend of coal-tyre (1:1 in organic matter) in two reactors, tubing bomb and autoclave reactors (TBR, AR)), on PAH formation has been studied.Gas chromatography/mass spectrometry (GC/MS) is used as the main analytical technique after fractionation into four chemical fractions using neutral alumina column chromatography (CC). As the complementary technique, thin layer chromatography with flame ionisation detector (TLC/FID) was used to compare the analytical tool on the total aromatic compounds, leading to the conclusion that the nature of synthetic oils is also dependent on the analytical technique.In relation to the variables studied, the lower the pressure the higher the concentration of PAH detected. The hydrogen abundance reduces the PAH content. The hydropyrolysis of tyre, coal, and a blend of coal-tyre at the same conditions show that coal produces higher concentrations of PAH at hydrogenating conditions. PAHs that contain three and four cycles are the main PAHs detected regardless of the feed.

  16. Abundances of polycyclic aromatic hydrocarbons (PAHs) in 14 chinese and american coals and their relation to coal rank and weathering

    Science.gov (United States)

    Wang, R.; Liu, Gaisheng; Zhang, Jiahua; Chou, C.-L.; Liu, J.

    2010-01-01

    The abundances of 16 polycyclic aromatic hydrocarbons (PAHs) on the priority list of the United States Environmental Protection Agency (U.S. EPA) have been determined in 14 Chinese and American coals. The ranks of the samples range from lignite, bituminous coal, anthracite, to natural coke. Soxhlet extraction was conducted on each coal for 48 h. The extract was analyzed on a gas chromatograph-mass spectrometer (GC-MS). The results show that the total PAH content ranged from 0.31 to 57.6 ??g/g of coal (on a dry basis). It varied with coal rank and is highest in the maturity range of bituminous coal rank. High-molecular-weight (HMW) PAHs are predominant in low-rank coals, but low-molecular-weight (LMW) PAHs are predominant in high-rank coals. The low-sulfur coals have a higher PAH content than high-sulfur coals. It may be explained by an increasing connection between disulfide bonds and PAHs in high-sulfur coal. In addition, it leads us to conclude that the PAH content of coals may be related to the depositional environment. ?? 2010 American Chemical Society.

  17. Lichens biomonitoring as feasible methodology to assess air pollution in natural ecosystems: combined study of quantitative PAHs analyses and lichen biodiversity in the Pyrenees Mountains.

    Science.gov (United States)

    Blasco, María; Domeño, Celia; Nerín, Cristina

    2008-06-01

    The air quality in the Aragón valley, in the central Pyrenees, has been assessed by evaluation of lichen biodiversity and mapped by elaboration of the Index of Air Purity (IAP) based on observations of the presence and abundance of eight kinds of lichen with different sensitivity to air pollution. The IAP values obtained have been compared with quantitative analytical measures of 16 PAHs in the lichen Evernia prunastri, because this species was associated with a wide range of traffic exposure and levels of urbanization. Analyses of PAHs were carried out by the DSASE method followed by an SPE clean-up step and GC-MS analysis. The concentration of total PAHs found in lichen samples from the Aragón valley ranged from 692 to 6420 ng g(-1) and the PAHs profile showed predominance of compounds with three aromatic rings. The influence of the road traffic in the area has been shown because values over the median concentration of PAHs (>1092 ng g(-1)), percentage of combustion PAHs (>50%), and equivalent toxicity (>169) were found in lichens collected at places exposed to the influence of traffic. The combination of both methods suggests IAP as a general method for evaluating the air pollution referenced to PAHs because it can be correlated with the content of combustion PAHs and poor lichen biodiversity can be partly explained by the air pollution caused by specific PAHs.

  18. A highly sensitive monoclonal antibody based biosensor for quantifying 3–5 ring polycyclic aromatic hydrocarbons (PAHs in aqueous environmental samples

    Directory of Open Access Journals (Sweden)

    Xin Li

    2016-03-01

    Full Text Available Immunoassays based on monoclonal antibodies (mAbs are highly sensitive for the detection of polycyclic aromatic hydrocarbons (PAHs and can be employed to determine concentrations in near real-time. A sensitive generic mAb against PAHs, named as 2G8, was developed by a three-step screening procedure. It exhibited nearly uniformly high sensitivity against 3-ring to 5-ring unsubstituted PAHs and their common environmental methylated PAHs, with IC50 values between 1.68 and 31 μg/L (ppb. 2G8 has been successfully applied on the KinExA Inline Biosensor system for quantifying 3–5 ring PAHs in aqueous environmental samples. PAHs were detected at a concentration as low as 0.2 μg/L. Furthermore, the analyses only required 10 min for each sample. To evaluate the accuracy of the 2G8-based biosensor, the total PAH concentrations in a series of environmental samples analyzed by biosensor and GC–MS were compared. In most cases, the results yielded a good correlation between methods. This indicates that generic antibody 2G8 based biosensor possesses significant promise for a low cost, rapid method for PAH determination in aqueous samples. Keywords: Monoclonal antibody, PAH, Pore water, Biosensor, Pyrene

  19. Effect of rhamnolipids on the uptake of PAHs by ryegrass

    International Nuclear Information System (INIS)

    Zhu Lizhong; Zhang Ming

    2008-01-01

    A hydroponic experiment was conducted to investigate the effect of rhamnolipids, a biosurfactant, on the uptake of polycyclic aromatic hydrocarbons (PAHs) by ryegrass. Results showed that rhamnolipids could enhance the uptake of PAHs by ryegrass roots. With increasing concentration of rhamnolipids, the PAH content in ryegrass roots initially increased and then decreased, while the PAH content in ryegrass shoots did not change. Batch studies also showed that the sorption of phenanthrene by fresh ryegrass roots was dependent on rhamnolipid concentration and showed the same trends as the uptake experiment. The increase of permeability of ryegrass root cells with the increase of rhamnolipid concentration may lead to the initial enhancement of PAH content in ryegrass roots, and the decrease of PAH adsorption onto the root surface with further increase of rhamnolipids led to the decrease of PAH content in ryegrass roots. - Rhamnolipids, a biosurfactant, can promote the uptake of PAHs by ryegrass, which indicates a potential application of surfactant-enhanced phytoremediation

  20. Effect of rhamnolipids on the uptake of PAHs by ryegrass

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Lizhong [Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang 310028 (China); Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, Zhejiang University, Hangzhou, Zhejiang 310029 (China)], E-mail: zlz@zju.edu.cn; Zhang Ming [Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang 310028 (China)], E-mail: zhangming@zju.edu.cn

    2008-11-15

    A hydroponic experiment was conducted to investigate the effect of rhamnolipids, a biosurfactant, on the uptake of polycyclic aromatic hydrocarbons (PAHs) by ryegrass. Results showed that rhamnolipids could enhance the uptake of PAHs by ryegrass roots. With increasing concentration of rhamnolipids, the PAH content in ryegrass roots initially increased and then decreased, while the PAH content in ryegrass shoots did not change. Batch studies also showed that the sorption of phenanthrene by fresh ryegrass roots was dependent on rhamnolipid concentration and showed the same trends as the uptake experiment. The increase of permeability of ryegrass root cells with the increase of rhamnolipid concentration may lead to the initial enhancement of PAH content in ryegrass roots, and the decrease of PAH adsorption onto the root surface with further increase of rhamnolipids led to the decrease of PAH content in ryegrass roots. - Rhamnolipids, a biosurfactant, can promote the uptake of PAHs by ryegrass, which indicates a potential application of surfactant-enhanced phytoremediation.

  1. Laboratory characterization of PM emissions from combustion of wildland biomass fuels

    Energy Technology Data Exchange (ETDEWEB)

    Hosseini, SeyedEhsan; Urbanski, Shawn; Dixit, P.; Qi, L.; Burling, Ian R.; Yokelson, Robert; Johnson, Timothy J.; Shrivastava, ManishKumar B.; Jung, H.; Weise, David; Miller, J. Wayne; Cocker, David R.

    2013-09-09

    Particle emissions from open burning of southwestern (SW) and southeastern (SE) U.S. 17 fuel types during 77 controlled laboratory burns are presented. The fuels include SW 18 vegetation types: ceanothus, chamise/scrub oak, coastal sage scrub, California sagebrush, 19 manzanita, maritime chaparral, masticated mesquite, oak savanna, and oak woodland as 20 well as SE vegetation types: 1-year, 2-year rough, pocosin, chipped understory, 21 understory hardwood, and pine litter. The SW fuels burned at a higher Modified 22 Combustion Efficiency (MCE) than the SE fuels resulting in lower particulate matter 23 (PM) mass emission factor (EF). Particle size distributions for six fuels and particle 24 number emission or all fuels are reported. Excellent mass closure (slope = 1.00, r2=0.94) 25 between ions, metals, and carbon with total weight was obtained. Organic carbon 26 emission factors inversely correlated (= 0.72) with MCE, while elemental carbon (EC) 27 had little correlation with MCE (=0.10). The EC/total carbon (TC) ratio sharply 28 increased with MCE for MCEs exceeding 0.94. The average levoglucosan and total Poly 29 Aromatic Hydrocarbons (PAH) emissions factors ranged from 25-1272 mg/kg fuel and 30 1790-11300 μg/kg fuel, respectively. No correlation between MCE and emissions of 31 PAHs/levoglucosan was found. Additionally, PAH diagnostic ratios were observed to be 32 poor indicators of biomass burning. Large fuel-type and regional dependency was 33 observed in the emission rates of ammonium, nitrate, fluoride, chloride, sodium, and

  2. Composition and morphology characterization of exopolymeric substances produced by the PAH-degrading fungus of Mucor mucedo.

    Science.gov (United States)

    Jia, Chunyun; Li, Xiaojun; Allinson, Graeme; Liu, Changfeng; Gong, Zongqiang

    2016-05-01

    To explore the role of exopolymeric substances (EPS) in the process of polycyclic aromatic hydrocarbons (PAH) biodegradation, the characteristics of EPS isolated from a PAH-degrading fungus were investigated firstly by spectrometric determination, microscopic observation, Fourier transform-infrared spectroscopy (FT-IR), and three-dimensional excitation-emission matrix fluorescence spectroscopy (3D-EEM), and then the PAH-degrading ability of isolated EPS was evaluated. The EPS compositions and morphology varied significantly with the extraction methods. EPS were mainly composed of proteins, carbohydrate, and humic-like substances, and the cation exchange resin (CER)-extracted EPS were granular while other EPS samples were all powders. Heating was the most effective treatment method, followed by the CER, centrifugation, and ultrasonication methods. However, 3D-EEM data demonstrated that heating treatment makes the mycelia lyse the most. Overall, therefore, the CER was the best EPS extraction method for Mucor mucedo (M. mucedo). The PAH degradation results indicated that 87 % of pyrene and 81 % of benzo[a]pyrene (B[a]P) were removed by M. mucedo over 12 days and 9 % more pyrene and 7 % more B[a]P were reduced after CER-extracted EPS addition of 465 mg l(-1). The investigation of EPS characterization and EPS enhancing PAH biodegradation is the premise for further in-depth exploration of the role of EPS contribution to PAH biodegradation.

  3. Soil efflux and total emission rates of magmatic CO2 at the horseshoe lake tree kill, mammoth mountain, California, 1995-1999

    Science.gov (United States)

    Gerlach, T.M.; Doukas, M.P.; McGee, K.A.; Kessler, R.

    2001-01-01

    We report the results of eight soil CO2 efflux surveys by the closed circulation chamber method at the Horseshoe Lake tree kill (HLTK) - the largest tree kill on Mammoth Mountain. The surveys were undertaken from 1995 to 1999 to constrain total HLTK CO2 emissions and to evaluate occasional efflux surveys as a surveillance tool for the tree kills. HLTK effluxes range from 1 to > 10,000 g m -2 day -1 (grams CO2 per square meter per day); they are not normally distributed. Station efflux rates can vary by 7-35% during the course of the 8- to 16-h surveys. Disturbance of the upper 2 cm of ground surface causes effluxes to almost double. Semivariograms of efflux spatial covariance fit exponential or spherical models; they lack nugget effects. Efflux contour maps and total CO2 emission rates based on exponential, spherical, and linear kriging models of survey data are nearly identical; similar results are also obtained with triangulation models, suggesting that the kriging models are not seriously distorted by the lack of normal efflux distributions. In addition, model estimates of total CO2 emission rates are relatively insensitive to the measurement precision of the efflux rates and to the efflux value used to separate magmatic from forest soil sources of CO2. Surveys since 1997 indicate that, contrary to earlier speculations, a termination of elevated CO2 emissions at the HLTK is unlikely anytime soon. The HLTK CO2 efflux anomaly fluctuated greatly in size and intensity throughout the 1995-1999 surveys but maintained a N-S elongation, presumably reflecting fault control of CO2 transport from depth. Total CO2 emission rates also fluctuated greatly, ranging from 46 to 136 t day-1 (metric tons CO2 per day) and averaging 93 t day-1. The large inter-survey variations are caused primarily by external (meteorological) processes operating on time scales of hours to days. The externally caused variations can mask significant changes occurring at depth; a striking example is

  4. Simple Bioremediation Treatments for the Removal of Polycyclic Aromatic Hydrocarbons (PAHs) from the Polluted Desert Soil of Kuwait

    International Nuclear Information System (INIS)

    Al-Gounaim, Marzooq Yousuf; Abu-Shady, Abdulsatar

    2004-01-01

    A soil microcosm test was designed to evaluate the influence of mixing polluted desert soil with clay soil (which is used as an amendment material and for immobilization of bacterial cells) on the biodegradation of petroleum polycyclic aromatic hydrocarbons (PAHs). Residual PAHs in this type of polluted soil were quantified by using GC analysis. At the begining of experiment 16 PAHs were resolved, of which the mutagenic and carcinogenic compounds flouranthene and pyrene were more frequent than the otherPAHs (14% and 12.4% respectively). Results of total PAH biodegradation show that mixing this polluted desert soil with clay soil or its water extract stimulated the biodegradation of 85.8%-89.1% of these compounds. This is contrast to 61.7%-75.5% in the absence of clay soil. Moreover when the mixed bacterial culture was immobilized in this clay soil 94.4% of total of total PAHs were degraded. On the other hand, the free cells of mixed culture succeeded to remove only 75.5% of these compounds. In this study the six-ranged PAHs were completely degraded in the presence of clay soil. A particularly notable distinction between the immobilized culture (T3) and other treatment in this biodegradation study is the greater efficiency of the immobilized culture to degrade the individuals of the 16 PAHs, especially the carcinogenic compounds: flouranthene, pyrene, chrysene, benzo(a) pyrene and dibenzo (a,h) anthracene. These results lead to the conclusion that mixing the polluted desert soil with clay soil and/or its water extract seems to be a simple cost effective bioremediation method. (author)

  5. A PAH growth mechanism and synergistic effect on PAH formation in counterflow diffusion flames

    KAUST Repository

    Wang, Yu; Raj, Abhijeet Dhayal; Chung, Suk-Ho

    2013-01-01

    was tested for ethylene premixed flames at low (20torr) and atmospheric pressures by comparing experimentally observed species concentrations with those of the computed ones for small chemical species and PAHs. As compared to several existing mechanisms

  6. Polycyclic Aromatic Hydrocarbons (PAHs) Levels in Two ...

    African Journals Online (AJOL)

    Polycyclic aromatic hydrocarbons (PAHs) concentrations were measured by gas chromatography with flame ionization detector (GC/FID) in two fish species, Sardinella maderensis (Flat sardinella) and Galeoides decadactylus (Lesser African threadfin or Shine-nose or Common threadfin) from Ghanaian coastal waters and ...

  7. Determination of polynuclear aromatic hydrocarbons (PAHs) in ...

    African Journals Online (AJOL)

    AJB SERVER

    2006-11-02

    Nov 2, 2006 ... (PAHs) in selected water bodies in the Niger Delta. Chimezie Anyakora and ... production, foundries), transportation, burning (e.g. forest, straw, agriculture ..... the Red Sea Coast of Yemen (DouAbul et al., 1997), a comparable ...

  8. Polycyclic aromatic hydrocarbons (PAHs) skin permeation rates change with simultaneous exposures to solar ultraviolet radiation (UV-S).

    Science.gov (United States)

    Hopf, Nancy B; Spring, Philipp; Hirt-Burri, Nathalie; Jimenez, Silvia; Sutter, Benjamin; Vernez, David; Berthet, Aurelie

    2018-05-01

    Road construction workers are simultaneously exposed to two carcinogens; solar ultraviolet (UV-S) radiation and polycyclic aromatic hydrocarbons (PAHs) in bitumen emissions. The combined exposure may lead to photogenotoxicity and enhanced PAH skin permeation rates. Skin permeation rates (J) for selected PAHs in a mixture (PAH-mix) or in bitumen fume condensate (BFC) with and without UV-S co-exposures were measured with in vitro flow-through diffusion cells mounted with human viable skin and results compared. Possible biomarkers were explored. Js were greater with UV-S for naphthalene, anthracene, and pyrene in BFC (0.08-0.1 ng/cm 2 /h) compared to without (0.02-0.26 ng/cm 2 /h). This was true for anthracene, pyrene, and chrysene in the PAH-mix. Naphthalene and benzo(a)pyrene (BaP) in the PAH-mix had greater Js without (0.97-13.01 ng/cm 2 /h) compared to with UV-S (0.40-6.35 ng/cm 2 /h). Time until permeation (T lags ) in the PAH-mix were generally shorter compared to the BFC, and they ranged from 1 to 13 h. The vehicle matrix could potentially be the reason for this discrepancy as BFC contains additional not identified substances. Qualitative interpretation of p53 suggested a dose-response with UV-S, and somewhat with the co-exposures. MMP1, p65 and cKIT were not exploitable. Although not statistically different, PAHs permeate human viable skin faster with simultaneous exposures to UV. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Polycyclic Aromatic Hydrocarbons (PAHs in the atmosphere of the Baltic Sea Region

    Directory of Open Access Journals (Sweden)

    Julia Gaffke

    2016-03-01

    Full Text Available The paper presents a review of publications on the concentrations of polycyclic aromatic hydrocarbons in the atmosphere of the Baltic Sea Region (BSR. It indicates the main emission sources of these substances, related to anthropogenic activity. These include incomplete combustion of fuels in engines on land and from marine transportation, as well as the burning of coal in the community sector. High PAH concentrations in the air are also related to increased industrial activity in urban areas. In the Baltic Sea Region, Germany and Poland have been determined to be responsible for the greatest proportion of PAH emissions. However, the highest number of exceedances of the accepted annual norm for benzo(apyrene concentrations was recorded in Poland.

  10. [Characteristics and sources of particulate polycyclic aromatic hydrocarbons (PAHs) during haze period in Guangzhou].

    Science.gov (United States)

    Duan, Jing-Chun; Tan, Ji-Hua; Sheng, Guo-Ying; Fu, Jia-Mo

    2009-06-15

    PM10 (particulates matter with aerodynamic diameter Guangzhou city between March 2002 and June 2003. Polycyclic aromatic hydrocarbons (PAHs) were studied during haze and non-haze periods in both summer and winter. PAHs pollution was serious in haze period compared with that in non-haze period, especially in winter. Compared with non-haze period, Phe, Ant, Flu, Pyr, BaA, Chr, IcdP, DahA and BghiP were more abundant in haze period in summer, and BaF, BeP, BaP, Pery, IcdP, DahA and BghiP were more abundant in haze period in winter. The BEQ values were 3.5 ng x m(-3), 3.35 ng x m(-3), 1.43 ng x m(-3) and 13.0 ng x m(-3) in non-haze in summer, in haze in summer, in non-haze in winter and in haze in winter, respectively. The BEQ values in non-haze in summer, in haze in summer and in non-haze in winter in Guangzhou (average: 2.76 ng x m(-3)) were relatively low in Chinese cities, and comparable with oversea cities. However, the BEQ value in haze in winter was relatively high in Chinese cities. It indicated that haze in winter would impair human health seriously. The diagnostic ratios suggested gasoline and diesel vehicle emission were main sources of PAHs in summer, and diesel vehicle and coal combustion emission were main sources of PAHs in winter; PAHs may come from both local sources and long-range transportation in non-haze in winter.

  11. Polycyclic aromatic hydrocarbons (PAHs) in wetland soils under different land uses in a coastal estuary: toxic levels, sources and relationships with soil organic matter and water-stable aggregates.

    Science.gov (United States)

    Xiao, Rong; Bai, Junhong; Wang, Junjing; Lu, Qiongqiong; Zhao, Qingqing; Cui, Baoshan; Liu, Xinhui

    2014-09-01

    The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) were determined in the soils from industrial, wharf, cropland, milldam and natural wetland sites to characterize their distributions, toxic levels and possible sources in the Pearl River Estuary and identify their relationships with soil organic matter (SOM) and water-stable aggregates (WSAs). Our results indicate that the average concentration of total PAHs in this region reached a moderate pollution level, which was higher than that in other larger estuaries in Asia. The average level of total PAHs in industrial soils was 1.2, 1.5, 1.6 and 2.3 times higher than those in soils from wharf, cropland, milldam and natural wetland sites, respectively. Greater accumulation of PAHs occurred in the middle and/or bottom soil layers where 3-ring PAHs were dominant. Industrial soils also exhibited the highest toxic levels with the highest toxic equivalent concentrations of PAHs, followed by wharf and milldam soils, and the cropland and wetland soils had the lowest toxicity. The diagnostic ratios suggested that PAHs primarily originated from biomass and coal combustion at industrial and milldam sites, and petroleum combustion was determined to be the primary source of PAHs at the wharf, cropland and wetland sites. Both 3-ring and 4-ring PAHs in the milldam and wharf soils were significantly positively correlated with the SOM, whereas the 4,5,6-ring PAHs and total PAHs in industrial soils and the 2-ring PAHs in cropland soils were significantly negatively correlated with the SOM. In addition, large WSAs also exhibited a significant positive correlation with PAHs. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Addition of biochar to sewage sludge decreases freely dissolved PAHs content and toxicity of sewage sludge-amended soil.

    Science.gov (United States)

    Stefaniuk, Magdalena; Oleszczuk, Patryk

    2016-11-01

    Due to an increased content of polycyclic aromatic hydrocarbons (PAHs) frequently found in sewage sludges, it is necessary to find solutions that will reduce the environmental hazard associated with their presence. The aim of this study was to determine changes of total and freely dissolved concentration of PAHs in sewage sludge-biochar-amended soil. Two different sewage sludges and biochars with varying properties were tested. Biochars (BC) were produced from biogas residues at 400 °C or 600 °C and from willow at 600 °C. The freely dissolved PAH concentration was determined by means of passive sampling using polyoxymethylene (POM). Total and freely dissolved PAH concentration was monitored at the beginning of the experiment and after 90 days of aging of the sewage sludge with the biochar and soil. Apart from chemical evaluation, the effect of biochar addition on the toxicity of the tested materials on bacteria - Vibrio fischeri (Microtox ® ), plants - Lepidium sativum (Phytotestkit F, Phytotoxkit F), and Collembola - Folsomia candida (Collembolan test) was evaluated. The addition of biochar to the sewage sludges decreased the content of C free PAHs. A reduction from 11 to 43% of sewage sludge toxicity or positive effects on plants expressed by root growth stimulation from 6 to 25% to the control was also found. The range of reduction of C free PAHs and toxicity was dependent on the type of biochar. After 90 days of incubation of the biochars with the sewage sludge in the soil, C free PAHs and toxicity were found to further decrease compared to the soil with sewage sludge alone. The obtained results show that the addition of biochar to sewage sludges may significantly reduce the risk associated with their environmental use both in terms of PAH content and toxicity of the materials tested. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Tenax TA extraction to understand the rate-limiting factors in methyl-β-cyclodextrin-enhanced bioremediation of PAH-contaminated soil.

    Science.gov (United States)

    Sun, Mingming; Luo, Yongming; Teng, Ying; Christie, Peter; Jia, Zhongjun; Li, Zhengao

    2013-06-01

    The effectiveness of many bioremediation systems for PAH-contaminated soil may be constrained by low contaminant bioaccessibility due to limited aqueous solubility or large sorption capacity. Information on the extent to which PAHs can be readily biodegraded is of vital importance in the decision whether or not to remediate a contaminated soil. In the present study the rate-limiting factors in methyl-β-cyclodextrin (MCD)-enhanced bioremediation of PAH-contaminated soil were evaluated. MCD amendment at 10 % (w/w) combined with inoculation with the PAH-degrading bacterium Paracoccus sp. strain HPD-2 produced maximum removal of total PAHs of up to 35 %. The desorption of PAHs from contaminated soil was determined before and after 32 weeks of bioremediation. 10 % (w/w) MCD amendment (M2) increased the Tenax extraction of total PAHs from 12 to 30 % and promoted degradation by up to 26 % compared to 6 % in the control. However, the percentage of Tenax extraction for total PAHs was much larger than that of degradation. Thus, in the control and M2 treatment it is likely that during the initial phase the bioaccessibility of PAHs is high and biodegradation rates may be limited by microbial processes. On the other hand, when the soil was inoculated with the PAH-degrading bacterium (CKB and MB2), the slowly and very slowly desorbing fractions (F sl and F vl ) became larger and the rate constants of slow and very slow desorption (k sl and k vl ) became extremely small after bioremediation, suggesting that desorption is likely rate limiting during the second, slow phase of biotransformation. These results have practical implications for site risk assessment and cleanup strategies.

  14. In situ phytoremediation of PAH-contaminated soil by intercropping alfalfa (Medicago sativa L.) with tall fescue (Festuca arundinacea Schreb.) and associated soil microbial activity

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Mingming; Fu, Dengqiang; Teng, Ying; Shen, Yuanyuan; Luo, Yongming; Li, Zhengao [Chinese Academy of Sciences, Nanjing (China). Key Laboratory of Soil Environment and Pollution Remediation; Christie, Peter [Agri-Food and Biosciences Institute, Belfast (United Kingdom). Agri-Environment Branch

    2011-09-15

    Purpose: A 7-month field experiment was conducted to investigate the polycyclic aromatic hydrocarbon (PAH) remediation potential of two plant species and changes in counts of soil PAH-degrading bacteria and microbial activity. Materials and methods: Alfalfa and tall fescue were grown in monoculture and intercropped for 7 months in contaminated field soil. Soil and plant samples were analyzed for PAHs. Plant biomass, densities of PAH-degradation soil bacteria, soil microbial biomass C and N, enzyme activities, and the physiological profile of the soil microbial community were determined. Results and discussion: Average removal percentage of total PAHs in intercropping (30.5%) was significantly higher than in monoculture (19.9%) or unplanted soil (-0.6%). About 7.5% of 3-ring, 12.3% of 4-ring, and 17.2% of 5(+6)-ring PAHs were removed from the soil by alfalfa, with corresponding values of 25.1%, 10.4%, and 30.1% for tall fescue. Intercropping significantly enhanced the remediation efficiency. About 18.9% of 3-ring, 30.9% of 4-ring, and 33.4% of 5(+6)-ring PAHs were removed by the intercropping system. Higher counts of soil culturable PAH-degrading bacteria and elevated microbial biomass and enzyme activities were found after intercropping. Soil from intercropping showed significantly higher (p < 0.05) average well-color development obtained by the BIOLOG Ecoplate assay and Shannon-Weaver index compared with monoculture. Conclusions: Cropping promoted the dissipation of soil PAHs. Tall fescue gave greater removal of soil PAHs than alfalfa, and intercropping was more effective than monoculture. Intercropping of alfalfa and tall fescue may be a promising in situ bioremediation strategy for PAH-contaminated soils. (orig.)

  15. Characterization of particle bound organic carbon from diesel vehicles equipped with advanced emission control technologies.

    Science.gov (United States)

    Pakbin, Payam; Ning, Zhi; Schauer, James J; Sioutas, Constantinos

    2009-07-01

    A chassis dynamometer study was carried out by the University of Southern California in collaboration with the Air Resources Board (CARB) to investigate the physical, chemical, and toxicological characteristics of diesel emissions of particulate matter (PM) from heavy-duty vehicles. These heavy-duty diesel vehicles (HDDV) were equipped with advanced emission control technologies, designed to meet CARB retrofit regulations. A HDDV without any emission control devices was used as the baseline vehicle. Three advanced emission control technologies; continuously regenerating technology (CRT), zeolite- and vanadium-based selective catalytic reduction technologies (Z-SCRT and V-SCRT), were tested under transient (UDDS) (1) and cruise (80 kmph) driving cycles to simulate real-world driving conditions. This paper focuses on the characterization of the particle bound organic species from the vehicle exhaust. Physical and chemical properties of PM emissions have been reported by Biswas et al. Atmos. Environ. 2008, 42, 5622-5634) and Hu et al. (Atmos. Environ. 2008, submitted) Significant reductions in the emission factors (microg/mile) of particle bound organic compounds were observed in HDDV equipped with advanced emission control technologies. V-SCRT and Z-SCRT effectively reduced PAHs, hopanes and steranes, n-alkanes and acids by more than 99%, and often to levels below detection limits for both cruise and UDDS cycles. The CRT technology also showed similar reductions with SCRT for medium and high molecular weight PAHs, acids, but with slightly lower removal efficiencies for other organic compounds. Ratios of particle bound organics-to-OC mass (microg/g) from the baseline exhaust were compared with their respective ratios in diesel fuel and lubricating oil, which revealed that hopanes and steranes originate from lubricating oil, whereas PAHs can either form during the combustion process or originate from diesel fuel itself. With the introduction of emission control

  16. Natural organic matter to enhance electrokinetic transport of PAH

    Energy Technology Data Exchange (ETDEWEB)

    Suer, P.; Joensson, S.; Allard, B. [Man-Technology-Environment Research Centre, Oerebro Univ. (Sweden)

    2001-07-01

    The remediation of contaminated soil can be enhanced with natural organic matter (NOM) as a complexing agent for pollutants. NOM has both hydrophobic and acidic properties, so that it is charged and thus subject to electroremediation. At the same time many contaminants have a high affinity for organic matter. Organic matter was produced in situ in an electric field or added in solute form. The resulting dissolved organic matter was transported towards the cathode, probably by cationic colloids. Produced dissolved organic matter included high molecular weight molecules near the cathode, at the site of pH buffering. Pyrene and phenanthrene were likewise transported towards the cathode. Movement was small but distinctive in 2-day experiments. Clay influence the soil/water distribution of the PAH but no effect on the total transport could be discerned. The presence of solid organic matter in the soil removed all PAH from the water phase, even though the concentration of organic matter in the water phase was high as well. (orig.)

  17. Atmospheric concentrations, sources and gas-particle partitioning of PAHs in Beijing after the 29th Olympic Games

    Energy Technology Data Exchange (ETDEWEB)

    Ma Wanli [International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Sun Dezhi [International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083 (China); Shen Weiguo [College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083 (China); Yang Meng [IJRC-PTS, Dalian Maritime University, Dalian (China); Qi Hong; Liu Liyan; Shen Jimin [International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Li Yifan, E-mail: ijrc_pts_paper@yahoo.com [International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Science and Technology Branch, Environment C