Sample records for aromatic hydrocarbon content

  1. Mutagenecity and contents of polycyclic aromatic hydrocarbons in new high-viscosity naphthenic oils and used and recycled mineral oils

    Microsoft Academic Search

    Manuela Granella; Cinzia Ballarin; Barbara Nardini; Marscia Marchioro; Erminio Clonfero

    1995-01-01

    Mutagenic activity on the Ames test was evaluated in 15 samples of naphthenic high-viscosity minerals oils and 12 samples of used lubricants (recovered and pooled) and their recycled products. Bacterial mutagenesis was assayed using both the standard technique and Blackburn's modification. The contents of polycyclic aromatic hydrocarbons (PAH) was also evaluated, as polynuclear aromatic fraction (PAF) and total PAH, determined

  2. Combustion aerosol water content and its effect on polycyclic aromatic hydrocarbon reactivity

    NASA Astrophysics Data System (ADS)

    Mcdow, Stephen R.; Vartiainen, Matti; Sun, Qingrui; Hong, Yusen; Yao, Yilin; Kamens, Richard M.

    A linear relationship was observed between particle water uptake and relative humidity for aerosol samples collected on Teflon coated glass fiber filters. Gasoline soot and wood smoke sample weight increases were three to five times greater than diesel soot weight increases at comparable relative humidities. Lower limit estimates of wood smoke water content at 90% relative humidity were in the 5-10% range. Based on these results polycyclic aromatic hydrocarbon photodegradation was investigated in liquid mixtures of actual wood smoke components with water content varied from 0 to 15%. Reaction rates of benz[a]anthracene and benzo[k]fluroanthene were significantly greater in methoxyphenol mixtures with 10% water content than in mixtures which did not contain water. Benzo[a]pyrene photodegradation was not significantly different. The results indicate that combustion particle water content increases with increasing relative humidity and that PAH photodegradation rates are likely to increase with increasing particle water content. This provides an explanation for previously described smog chamber studies in which a correlation between polycyclic aromatic hydrocarbon (PAH) decay in sunlight and water vapor concentration was reported.

  3. [Characterization of the content of polycyclic aromatic hydrocarbons in the cold- and hot-smoked fish].

    PubMed

    Kim, I N; Kim, G N; Krivosheeva, L V; Khitrovo, I A

    1999-01-01

    The carcinogenic danger of the commercial smoked herring was assessed. The edible part of the smoked herring contains 16 polycyclic aromatic hydrocarbons whose bulk consists of phenanthrene, pyrene, floranthene, and benzo(b)fluoranthene. The content of benzo(a)pyrene (BP) in the cold and hot smoked herring are 189 and 291 ng/kg, respectively. It is lower than the present standard values. The proportion of carcinogenic danger of BP is 32% for cold smoked herring and 34% for hot smoked herring. PMID:10465871

  4. Superconductivity in aromatic hydrocarbons

    NASA Astrophysics Data System (ADS)

    Kubozono, Yoshihiro; Goto, Hidenori; Jabuchi, Taihei; Yokoya, Takayoshi; Kambe, Takashi; Sakai, Yusuke; Izumi, Masanari; Zheng, Lu; Hamao, Shino; Nguyen, Huyen L. T.; Sakata, Masafumi; Kagayama, Tomoko; Shimizu, Katsuya

    2015-07-01

    'Aromatic hydrocarbon' implies an organic molecule that satisfies the (4n + 2) ?-electron rule and consists of benzene rings. Doping solid aromatic hydrocarbons with metals provides the superconductivity. The first discovery of such superconductivity was made for K-doped picene (Kxpicene, five benzene rings). Its superconducting transition temperatures (Tc's) were 7 and 18 K. Recently, we found a new superconducting Kxpicene phase with a Tc as high as 14 K, so we now know that Kxpicene possesses multiple superconducting phases. Besides Kxpicene, we discovered new superconductors such as Rbxpicene and Caxpicene. A most serious problem is that the shielding fraction is ?15% for Kxpicene and Rbxpicene, and it is often ?1% for other superconductors. Such low shielding fractions have made it difficult to determine the crystal structures of superconducting phases. Nevertheless, many research groups have expended a great deal of effort to make high quality hydrocarbon superconductors in the five years since the discovery of hydrocarbon superconductivity. At the present stage, superconductivity is observed in certain metal-doped aromatic hydrocarbons (picene, phenanthrene and dibenzopentacene), but the shielding fraction remains stubbornly low. The highest priority research area is to prepare aromatic superconductors with a high superconducting volume-fraction. Despite these difficulties, aromatic superconductivity is still a core research target and presents interesting and potentially breakthrough challenges, such as the positive pressure dependence of Tc that is clearly observed in some phases of aromatic hydrocarbon superconductors, suggesting behavior not explained by the standard BCS picture of superconductivity. In this article, we describe the present status of this research field, and discuss its future prospects.

  5. Polycyclic Aromatic Hydrocarbons

    NSDL National Science Digital Library

    The featured molecules for the month of February are a number of polycyclic aromatic hydrocarbons (PAHs) discussed in the article "Fluorescence, Absorption, and Excitation Spectra of Polycyclic Aromatic Hydrocarbons as a Tool for Quantitative Analysis". PAHs are ubiquitous in air, soils, and water as a result of both direct and indirect emissions. PAHs are discharged into environments as byproducts of the combusion of fossil fuels used for transportation and generation of electricity. Other sources of PAH emissions include industrial processes, biomass burning, waste incineration, oil spills, and cigarette smoke.

  6. Changes in the contents of selected polycyclic aromatic hydrocarbons in soils of various types.

    PubMed

    Banach-Szott, Magdalena; Debska, Bozena; Wisniewska, Alicja; Pakula, Jaroslaw

    2015-04-01

    The aim of the paper was to determine the stability and the decomposition intensity of selected polycyclic aromatic hydrocarbons (fluorene, anthracene, pyrene, and chrysene) in soils that are under agricultural use. Soil was sampled from the arable layer that is representative of the Kujawy and Pomorze Provinces, which are located in the northwestern part of Poland. The soil samples were polluted with selected PAHs at an amount corresponding to 10 mg PAHs/kg. PAH-polluted soil samples were incubated for 10, 30, 60, 120, 180, and 360 days at a temperature of 20-25 °C and a fixed moisture of 50% field water capacity. High-performance liquid chromatography (HPLC) was used to determine the content of PAHs. It was found that the process of the degradation of PAHs was most intensive during the first 30 days of the experiment; however, three-ring PAHs (fluorene and anthracene) definitely decomposed faster than the four-ring ones (pyrene and chrysene). The results also confirm the significant role of soil organic matter in sorption and activation processes of PAHs. PMID:25586610

  7. Influence of soil fertilization by sewage sludge on the content of polycyclic aromatic hydrocarbons (PAHs) in crops.

    PubMed

    Oleszczuk, Patryk; Baran, Stanis?aw

    2005-01-01

    The aim of the present study was an evaluation of the influence of the addition of different sewage sludge doses on the uptake of polycyclic aromatic hydrocarbons from fertilized soil. Sewage sludge was introduced into the soil in the following doses: 30, 75, 150, 300, and 600 Mg/ha. The content of polycyclic aromatic hydrocarbons (PAH) was determined by means of HPLC-UV method. The addition of increasing doses of sludge into the soil resulted in a gradual increase in the amount of the polycyclic aromatic hydrocarbons contained therein. During the period of the study, continuous changes in the content of all the compounds studied were found in all the experimental variants. Finally, on the last day of the study, the highest degree of degradation (73%) of 16 PAHs' sum (US EPA) was noted for sludge doses of 30 and 300 Mg/ha. In the case of individual PAHs, the change in their content differed and clearly depended on the sewage sludge dose. The introduction of sewage sludge into the soil influenced the increase of the sum of 16 PAHs in the plants grown in this soil. The influence mentioned above depended on the sewage sludge dose and the plant species grown, as well as the PAH content in the soil. The evaluation of individual PAHs in plants showed an increase in their content with the increase of the amount of sewage sludge. A statistically significant increase in their content was most often observed for sewage sludge doses above 150 Mg/ha. Moreover, it was found that fertilization of the soil with sewage sludge resulted in pollution of the plants with PAHs of high molecular weight. PMID:16287643

  8. Polycyclic aromatic hydrocarbon bioremediation design

    Microsoft Academic Search

    Shigeaki Harayama

    1997-01-01

    Many polycyclic aromatic hydrocarbons (PAHs) are known to be mutagenic or carcinogenic, and their contamination in soil and aquifer is of great environmental concern. Limited numbers of microorganisms including mycobacteria, Sphingomonas and white rot fungi were found to be capable of degrading PAHs with four or more fused aromatic rings. In white rot fungi, lignin peroxidases are believed to be

  9. Polycyclic Aromatic Hydrocarbons

    NASA Technical Reports Server (NTRS)

    Salama, Farid

    2010-01-01

    Carbonaceous materials play an important role in space. Polycyclic Aromatic Hydrocarbons (PAHs) are a ubiquitous component of the carbonaceous materials. PAHs are the best-known candidates to account for the IR emission bands. They are also thought to be among the carriers of the diffuse interstellar absorption bands (DIBs). 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 is to reproduce in the laboratory the physical conditions that exist in the emission and absorption interstellar zones. The harsh physical conditions of the ISM -low temperature, collisionless, strong UV radiation fields- are simulated in the laboratory by associating a molecular beam with an ionizing discharge to generate a cold plasma expansion. PAH ions and radicals are formed from the neutral precursors in an isolated environment at low temperature and probed with high-sensitivity cavity ringdown spectroscopy in the NUV-NIR range. Carbon nanoparticles are also formed during the short residence time of the precursors in the plasma and are characterized with time-offlight mass spectrometry. These experiments provide unique information on the spectra of large carbonaceous molecules and ions in the gas phase that can now be directly compared to interstellar and circumstellar observations (IR emission bands, DIBs, extinction curve). These findings also hold great potential for understanding the formation process of interstellar carbonaceous grains. We will review recent progress in the experimental and theoretical studies of PAHs, compare the laboratory data with astronomical observations and discuss the global implications.

  10. The Effect of Liquid Smoking of Anchovy (Engraulis encrasicolus, L. 1758) Fillets on Sensory, Meat Yield, Polycyclic Aromatic Hydrocarbon (PAH) Content, and Chemical Changes

    Microsoft Academic Search

    Zayde Alçiçek; Özge Zencir; Gül Çelik Çakiro?ullari; Hasan Hüseyin Atar

    2010-01-01

    In this study, the effects of a commercial liquid smoke flavoring agent and two different brining solutions applied on fillets of anchovy were investigated by performing sensory analyses, meat yield, polycyclic aromatic hydrocarbon (PAH) content, and chemical composition analyses. Fillets were brined at 40 and 65% for 4 h at 4°C. Meat yield, sensorial acceptability, and chemical compositions were affected

  11. AROMATIC HYDROCARBON DEGRADATION: A MOLECULAR APPROACH

    EPA Science Inventory

    Aromatic hydrocarbons have a ubiquitous distribution in nature. he majority of these compounds are formed through the pyrolysis of organic matter. yrolysis at high temperatures leads to the information of unsubstituted polycyclic aromatic hydrocarbons (1). yrolysis at low tempera...

  12. Chemistry on Polycyclic Aromatic Hydrocarbons

    NASA Astrophysics Data System (ADS)

    Hornekaer, Liv

    Chemistry on Polycyclic Aromatic Hydrocarbons Even though Polycyclic Aromatic Hydrocarbons (PAHs) are ubiquitous in the interstellar medium, the role they play as catalysts for interstellar chemistry is still largely unexplored. However, existing experimental data and theoretical calculations indicate that PAHs may well play a very active role, in particular in connection with the formation of molecular hydrogen. These findings may explain observations of increased molecular hydrogen formation rates in Photodissociation regions with high PAH abundances. In my talk I will present temperature programmed desorption data demonstrating the formation of highly super-hydrogenated PAHs via hydrogen addition reactions and catalytic formation of molecular hydrogen via abstraction reactions at a wide range of H atom temperatures. Approximate cross-sections for these reactions derived via model simulations will be presented. The implications for the role played by PAHs in interstellar chemistry will be discussed.

  13. Stabilization of sewage sludge by different biochars towards reducing freely dissolved polycyclic aromatic hydrocarbons (PAHs) content.

    PubMed

    Oleszczuk, Patryk; Zieli?ska, Anna; Cornelissen, Gerard

    2014-03-01

    The objective of the study was to identify the effect of various biochars on the content of freely dissolved (Cfree) PAHs in sewage sludge. Apart from the evaluation of biochars obtained from various materials, the study also included the determination of the effects of biochar particle sizes and biochar production temperature on their ability to bind PAHs in sewage sludge. Increase in biochar dose caused a gradual reduction of Cfree PAHs content, but only up to the biochar dose of 5%. Depending on the kind of initial material from which the biochar was produced, the reduction of Cfree PAHs content in sewage sludge varied from 17.4% to 58.0%. Both the temperature and the particle size of biochar had an effect on PAH free concentration reduction. Biochars characterised by a low polarity index (O/C or (O+N)/C) reduced the level of Cfree PAHs better than biochars with a higher polarity index value. PMID:24495539

  14. Combustion aerosol water content and its effect on polycyclic aromatic hydrocarbon reactivity

    Microsoft Academic Search

    Stephen R. Mcdow; Matti Vartiainen; Qingrui Sun; Yusen Hong; Yilin Yao; Richard M. Kamens

    1995-01-01

    A linear relationship was observed between particle water uptake and relative humidity for aerosol samples collected on Teflon coated glass fiber filters. Gasoline soot and wood smoke sample weight increases were three to five times greater than diesel soot weight increases at comparable relative humidities. Lower limit estimates of wood smoke water content at 90% relative humidity were in the

  15. Polycyclic aromatic hydrocarbons in carcinogenesis.

    PubMed Central

    Warshawsky, D

    1999-01-01

    A symposium on "Polycyclic Aromatic Hydrocarbons (PAHs) in Carcinogenesis" was presented at the third International Congress of Pathophysiology held in Lathi, Finland, 28 June-3 July 1998. The congress was also sponsored by the International Union of Biological Sciences and the International Society of Free Radical Research. Institutional support for the symposium included the Electric Power Research Institute, National Center for Toxicological Research, and EPA/National Health and Environmental Effects Research Laboratory and the Office of Solid Waste and Emergency Response. The symposium focused on the sources, carcinogenicity, genotoxicity, and risk assessment of individual and mixtures of PAHs that are found in solid wastes, Superfund sites, and other hazardous waste sites. Based on the occurrence of PAHs at numerous Superfund sites and the significant data gaps on the toxic potential of certain PAHs, the information developed during this symposium would be of value in assessing health risks of these chemicals at Superfund and other hazardous waste sites. PMID:10090712

  16. Polynuclear aromatic hydrocarbons for fullerene synthesis in flames

    DOEpatents

    Alford, J. Michael; Diener, Michael D.

    2006-12-19

    This invention provides improved methods for combustion synthesis of carbon nanomaterials, including fullerenes, employing multiple-ring aromatic hydrocarbon fuels selected for high carbon conversion to extractable fullerenes. The multiple-ring aromatic hydrocarbon fuels include those that contain polynuclear aromatic hydrocarbons. More specifically, multiple-ring aromatic hydrocarbon fuels contain a substantial amount of indene, methylnapthalenes or mixtures thereof. Coal tar and petroleum distillate fractions provide low cost hydrocarbon fuels containing polynuclear aromatic hydrocarbons, including without limitation, indene, methylnapthalenes or mixtures thereof.

  17. Lipid-content-normalized polycyclic aromatic hydrocarbons (PAHs) in the xylem of conifers can indicate historical changes in regional airborne PAHs.

    PubMed

    Kuang, Yuan-wen; Li, Jiong; Hou, En-qing

    2015-01-01

    The temporal variation of polycyclic aromatic hydrocarbons (PAHs) concentrations as well as the lipid content in the xylem of Masson pine trees sampled from the same site were determined and compared with the days of haze occurrence and with the historical PAHs reported in sedimentary cores. The patterns of the lipid content as well as the PAH concentrations based on the xylem dry weight (PAHs-DW) decreased from the heartwood to the sapwood. The trajectories of PAHs normalized by xylem lipid content (PAHs-LC) coincided well with the number of haze-occurred days and were partly similar with the historical changes in airborne PAHs recorded in the sedimentary cores. The results indicated that PAHs-LC in the xylem of conifers might reliably reflect the historical changes in airborne PAHs at a regional scale. The species-specificity should be addressed in the utility and application of dendrochemical monitoring on historical and comparative studies of airborne PAHs. PMID:25299794

  18. Infrared Spectra of Polycyclic Aromatic Hydrocarbons (PAHs)

    NASA Technical Reports Server (NTRS)

    Bauschlicher, Charles W., Jr.; Bakes, E. L. O.

    2000-01-01

    We have computed the synthetic infrared spectra of some polycyclic aromatic hydrocarbons containing up to 54 carbon atoms. The species studied include ovalene, circumcoronene, dicoronylene, and hexabenzocoronene. We report spectra for anions, neutrals, cations, and multiply charged cations.

  19. Effect of roasting conditions on the polycyclic aromatic hydrocarbon content in ground Arabica coffee and coffee brew.

    PubMed

    Houessou, Justin Koffi; Maloug, Saber; Leveque, Anne-Sophie; Delteil, Corine; Heyd, Bertrand; Camel, Valérie

    2007-11-14

    Roasting is a critical process in coffee production as it enables the development of flavor and aroma. At the same time, roasting may lead to the formation of nondesirable compounds, such as polycyclic aromatic hydrocarbons (PAHs). In this study, Arabica green coffee beans from Cuba were roasted under controlled conditions to monitor PAH formation during the roasting process. Roasting was performed in a pilot spouted bed roaster, with the inlet air temperature varying from 180 to 260 degrees C, using both dark (20 min) and light (5 min) roasting conditions. Several PAHs were determined in both roasted coffee samples and green coffee samples. Also, coffee brews, obtained using an electric coffee maker, were analyzed for final estimation of PAH transfer coefficients to the infusion. Formation of phenanthrene, anthracene, and benzo[a]anthracene in coffee beans was observed at temperatures above 220 degrees C, whereas formation of pyrene and chrysene required 260 degrees C. Low levels of benzo[g,h,i]perylene were also noted for dark roasting under 260 degrees C, with simultaneous partial degradation of three-cycle PAHs, suggesting that transformation of low molecular PAHs to high molecular PAHs occurs as the roasting degree is increased. The PAH transfer to the infusion was quite moderate (<35%), with a slightly lower extractability for dark-roasted coffee as compared to light-roasted coffee. PMID:17941690

  20. Polycyclic aromatic hydrocarbons in human fat and liver

    Microsoft Academic Search

    H. Obana; S. Hori; T. Kashimoto; N. Kunita

    1981-01-01

    Nine polycyclic aromatic hydrocarbons (PAH) were determined in human fat and liver by high pressure liquid column chromatography without complex pretreatment prior to analysis. Fat and liver tissue were obtained from autopsies. Smoking habits, occupations, and residence of the persons were unknown. The tissues were free from cancer. Differences of sex and age did not affect PAH content in the

  1. Polycyclic aromatic hydrocarbons: environmental pollution and bioremediation

    Microsoft Academic Search

    Sudip K Samanta; Om V Singh; Rakesh K Jain

    2002-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are widely distributed and relocated in the environment as a result of the incomplete combustion of organic matter. Many PAHs and their epoxides are highly toxic, mutagenic and\\/or carcinogenic to microorganisms as well as to higher systems including humans. Although various physicochemical methods have been used to remove these compounds from our environment, they have many

  2. Decreased mitochondrial DNA content in association with exposure to polycyclic aromatic hydrocarbons in house dust during wintertime: from a population enquiry to cell culture.

    PubMed

    Pieters, Nicky; Koppen, Gudrun; Smeets, Karen; Napierska, Dorota; Plusquin, Michelle; De Prins, Sofie; Van De Weghe, Hendrik; Nelen, Vera; Cox, Bianca; Cuypers, Ann; Hoet, Peter; Schoeters, Greet; Nawrot, Tim S

    2013-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are widespread environmental pollutants that are formed in combustion processes. At the cellular level, exposure to PAHs causes oxidative stress and/or some of it congeners bind to DNA, which may interact with mitochondrial function. However, the influence of these pollutants on mitochondrial DNA (mtDNA) content remains largely unknown. We determined whether indoor exposure to PAHs is associated with mitochondrial damage as represented by blood mtDNA content. Blood mtDNA content (ratio mitochondrial/nuclear DNA copy number) was determined by real-time qPCR in 46 persons, both in winter and summer. Indoor PAH exposure was estimated by measuring PAHs in sedimented house dust, including 6 volatile PAHs and 8 non-volatile PAHs. Biomarkers of oxidative stress at the level of DNA and lipid peroxidation were measured. In addition to the epidemiologic enquiry, we exposed human TK6 cells during 24 h at various concentrations (range: 0 to 500 µM) of benzo(a)pyrene and determined mtDNA content. Mean blood mtDNA content averaged (± SD) 0.95 ± 0.185. The median PAH content amounted 554.1 ng/g dust (25(th)-75(th) percentile: 390.7-767.3) and 1385 ng/g dust (25(th)-75(th) percentile: 1000-1980) in winter for volatile and non-volatile PAHs respectively. Independent for gender, age, BMI and the consumption of grilled meat or fish, blood mtDNA content decreased by 9.85% (95% CI: -15.16 to -4.2; p = 0.002) for each doubling of non-volatile PAH content in the house dust in winter. The corresponding estimate for volatile PAHs was -7.3% (95% CI: -13.71 to -0.42; p = 0.04). Measurements of oxidative stress were not correlated with PAH exposure. During summer months no association was found between mtDNA content and PAH concentration. The ability of benzo(a)pyrene (range 0 µM to 500 µM) to lower mtDNA content was confirmed in vitro in human TK6 cells. Based on these findings, mtDNA content can be a target of PAH toxicity in humans. PMID:23658810

  3. Origins of polycyclic aromatic hydrocarbons in estuarine sediments

    Microsoft Academic Search

    James L. Lake; Curtis Norwood; Crandall Dimock; Robert Bowen

    1979-01-01

    In order to determine the origin of polycyclic aromatic hydrocarbons (PAHs) in sediments from Narragansett Bay, Rhode Island, the PAH assemblages from the sediments and from possible origin materials were analyzed by gas Chromatographic and gas chromatographic-mass spectrometric techniques. Analyses included determinations of: 1. (1) the relative content of non-alkylated PAH parent molecules i.e. parent compound distributions (PCDs); 2. (2)

  4. Polycyclic aromatic hydrocarbon emissions from motorcycles

    Microsoft Academic Search

    Hsi-Hsien Yang; Lien-Te Hsieh; Hsu-Chung Liu; Hsiao-Hsuan Mi

    2005-01-01

    Emissions of polycyclic aromatic hydrocarbons (PAHs, 2–7 ring) and regulated air pollutants (CO, HC, NOx, PM) from 2-stroke carburetor (2-Stk\\/Cb), 4-stroke carburetor (4-Stk\\/Cb) and 4-stroke fuel injection (4-Stk\\/FI) motorcycles were investigated by testing these vehicles on a chassis dynamometer. Exhaust samplings were carried out on diluted exhausts in a dilution tunnel connected to a constant volume sampling system. Measurements were

  5. QUANTITATIVE ANALYSIS OF POLYNUCLEAR AROMATIC HYDROCARBONS IN LIQUID FUELS

    EPA Science Inventory

    Polynuclear aromatic hydrocarbons (PNAs), formed in combustion processes with liquid hydrocarbon fuels, contribute to mobile source exhaust emissions. Because correlation between PNA levels in automobile exhaust and pre-existent PNAs in fuel has been demonstrated in previous work...

  6. TRACE ANALYSIS FOR AROMATIC HYDROCARBONS IN NATURAL WATERS

    EPA Science Inventory

    A method of trace analysis of volatile aromatic hydrocarbons in natural water is described. The method is based on sparging water samples with nitrogen, adsorption of hydrocarbons on activated charcoal, followed by desorption into carbon disulfide and gas chromatographic analysis...

  7. Polycyclic Aromatic Hydrocarbons Content in Shoots and Leaves of Willow ( Salix viminalis ) Cultivated on the Sewage Sludge-Amended Soil

    Microsoft Academic Search

    Patryk Oleszczuk; Stanis?aw Baran

    2005-01-01

    The aim of the present study was to investigate the uptake of 16 PAHs by willow (Salix viminalis) from soil amended with contaminated sewage sludge. Uptake experiments were conducted on field plots using sludge applications\\u000a of 0, 30, 75, 150, 300, and 600 Mg ha?1. The total PAH content of control soil and sludge were 49.6 ?g kg?1 and 5713

  8. Analysis of the polycyclic aromatic hydrocarbon content of petrol and diesel engine lubricating oils and determination of DNA adducts in topically treated mice by 32P-postlabelling.

    PubMed

    Carmichael, P L; Jacob, J; Grimmer, G; Phillips, D H

    1990-11-01

    Engine lubricating oils are known to accumulate carcinogenic polycyclic aromatic hydrocarbons (PAHs) during engine running. Oils from nine petrol-powered and 11 diesel-powered vehicles, in addition to samples of unused oil, were analysed for PAH content and ability to form DNA adducts when applied topically to mouse skin. The levels of 19 PAHs, determined by GC, were in total, approximately 22 times higher in used oils from petrol engines than in oils from diesel engines. Male Parkes mice were treated with 50 microliters of oil daily for 4 days before they were killed and DNA isolated from skin and lung tissue. DNA samples were analysed by nuclease P1-enhanced 32P-postlabelling. Used oils from both diesel and petrol engines showed several adduct spots on PEI-cellulose plates at total adduct levels of up to 0.57 fmol/microgram DNA [approximately 60 times greater than in experiments with samples of unused oil in which adduct levels (0.01-0.02 fmol adducts/microgram DNA) were close to the limit of detection]. Higher adduct levels were generally formed by petrol engine oils than by diesel engine oils. Lung DNA contained similar total adduct levels to those in skin although the adduct maps were less complex. Total adduct levels correlated with extent of oil use in the engine, the total PAH concentration in oils and with the concentrations of certain individual PAHs present in the oils. An adduct spot that co-eluted with that of the major benzo[a]pyrene-DNA adduct accounted for 9-26% of the total adducts in skin DNA, and approximately 8% of the adducts in lung DNA, of mice treated with petrol engine oils. A major, and as yet unidentified, adduct spot comprised up to 30% of the total adducts in skin DNA, and up to 89% of the total adducts in lung DNA, of these animals. PMID:2225336

  9. Polycyclic aromatic hydrocarbons (PAHs) in subcutaneous biopsies of Mediterranean cetaceans

    E-print Network

    Hahn, Mark E.

    Polycyclic aromatic hydrocarbons (PAHs) in subcutaneous biopsies of Mediterranean cetaceans Letizia Abstract The aim of the present study was to measure polycyclic aromatic hydrocarbon (PAH) levels in free. A ®ngerprint of 14 PAHs was obtained for both species. In whales, the median value of total PAHs was 1970 ppb

  10. Effects of ozonation on mutagenic activity of polycyclic aromatic hydrocarbons

    Microsoft Academic Search

    Bruno Fouillet; Paul Chambon; Renée Chambon; Marcel Castegnaro; Nicole Weill

    1991-01-01

    Polycyclic aromatic hydrocarbons (PAH) represent a broad class of pollutants which are widely distributed in the environment (Neff 1979; Nikolaou et al. 1984) .These aromatic hydrocarbons are generated by incomplete combustion processes: many of them have been shown to possess mutagenic and carcinogenic activities (I.A.R.C. 1983). Therefore studies were undertaken in order to test the efficacy of various techniques to

  11. .. Polycyclic aromatic hydrocarbons in nearshore marine sediments of Australia*

    E-print Network

    Canberra, University of

    143 . .. Polycyclic aromatic hydrocarbons in nearshore marine sediments of Australia* W.A. Maher and J. Aislabiet Water Research Centre, University of Canberra, PO Box /, Belconnen,ACT 26/6, Australia aromatic hydrocarbons (PAH) in nearshore marine sediments of Australia isdiscussed. Available information

  12. Laboratory Investigation of Organic Aerosol Formation from Aromatic Hydrocarbons

    SciTech Connect

    Luisa T. Molina; Mario J. Molina; Renyi Zhang

    2006-08-23

    Our work for this DOE funded project includes: (1) measurements of the kinetics and mechanism of the gas-phase oxidation reactions of the aromatic hydrocarbons initiated by OH; (2) measurements of aerosol formation from the aromatic hydrocarbons; and (3) theoretical studies to elucidate the OH-toluene reaction mechanism using quantum-chemical and rate theories.

  13. Coumarin, Naphthalene, and Additional Polycyclic Aromatic Hydrocarbons

    NSDL National Science Digital Library

    The featured molecules this month are drawn from two papers. The first, "One-Pot Synthesis of 7-Hydroxy-3-carboxycoumarin in Water", is a Green Chemistry feature by Fringuelli, Piermatti, and Pizzo. The three-dimensional versions of the molecules in the synthesis of the coumarin derivative are directly tied to the reaction scheme included in the paper, opening the possibility of showing large numbers of complex synthetic pathways in this manner.The second paper is "Determining the Carbon-Carbon Distance in an Organic Molecule with a Ruler" by Simoni, Tubino, and Ricchi. This article describes an experiment to determine the size of a naphthalene molecule, using an extension of classic experiments for determining molecular size and Avogadro's number. While the structure of naphthalene will come as no surprise to most students, the molecule collection also includes additional polycyclic aromatic hydrocarbons (PAHs) that can be used to introduce students to the environmental and health issues related to these molecules.

  14. Ions colliding with polycyclic aromatic hydrocarbon clusters

    NASA Astrophysics Data System (ADS)

    Gatchell, M.; Zettergren, H.; Seitz, F.; Chen, T.; Alexander, J. D.; Stockett, M. H.; Schmidt, H. T.; ?awicki, A.; Rangama, J.; Rousseau, P.; Capron, M.; Maclot, S.; Maisonny, R.; Domaracka, A.; Adoui, L.; Méry, A.; Chesnel, J.-Y.; Manil, B.; Huber, B. A.; Cederquist, H.

    2013-09-01

    We have measured the ionization and fragmentation of polycyclic aromatic hydrocarbon (PAH) molecules and their clusters. We find that PAH clusters containing up to roughly 100 individual molecules fragment strongly following collisions with keV ions in low or high charge states (q). For both types of collisions, singly charged PAH molecules are found to be the dominant products but for very different reasons. A high-q ion projectile charge leads to strong multiple ionization of the PAH clusters and subsequent Coulomb explosions. A low-q ion projectile charge often leads to single ionization but stronger internal heating and long evaporation sequences with a singly charged PAH monomer as the end product. We have developed a Monte Carlo method for collision-induced heating of PAH clusters and present an evaporation model where the clusters cool slowly as most of the internal energies are stored in intramolecular vibrations and not in molecule-molecule vibrations.

  15. PHOTOTOXICITY OF POLYCYCLIC AROMATIC HYDROCARBONS IN COASTAL GREAT LAKES WATERS

    EPA Science Inventory

    Photoinduced toxicity is the exacerbated toxicity of environmental contaminants by UV radiation. Photoinduced toxicity of polycyclic aromatic hydrocarbons (PAHs) has been well established in the laboratory for numerous aquatic species including larval fish. The contaminants sub-p...

  16. POLYCYCLIC AROMATIC HYDROCARBON (PAH) EXPOSURE OF 257 PRESCHOOL CHILDREN

    EPA Science Inventory

    We investigated the polycyclic aromatic hydrocarbon (PAH) exposure of 257 preschool children and their adult caregivers in their everyday environments. Participants were recruited randomly from eligible homes and daycare centers within six North Carolina (NC) and six Ohio (OH) c...

  17. ENGINEERED ANTIBODIES FOR MONITORING OF POLYNUCLEAR AROMATIC HYDROCARBONS

    EPA Science Inventory

    The objective of this multidisciplinary project is to use molecular biological techniques to derive a set of antibodies with useful affinities and selectivities for recovery and detection of polynuclear aromatic hydrocarbons (PAHs) in environmental and biological samples. The lon...

  18. Biodegradability of select polycyclic aromatic hydrocarbon (pah) mixtures 

    E-print Network

    Desai, Anuradha M.

    2007-04-25

    Polycyclic aromatic hydrocarbons (PAHs) are environmentally significant because of their ubiquity and the toxicity of some. Their recalcitrance and persistence makes them problematic environmental contaminants. Microbial degradation is considered...

  19. CONSTRUCTING MICROBIAL STRAINS FOR DEGRADATION OF HALOGENATED AROMATIC HYDROCARBONS

    EPA Science Inventory

    The book chapter examines methods that have been used to isolate and to construct bacteria capable of growing aerobically with chlorinated aromatic compounds, including chlorinated hydrocarbons. It also describes some recent work in this area of research....

  20. Determination of aromatic hydrocarbons in urban air of Rome

    Microsoft Academic Search

    D. Brocco; R. Fratarcangeli; L. Lepore; M. Petricca; I. Ventrone

    1997-01-01

    Aromatic hydrocarbons were measured in Rome during 1992–1993 by means a differential optical absorption spectrometer (DOAS) and an automatic gas chromatograph (VOC analyzer). The mean distribution of aromatic hydrocarbons was: benzene 12.6%, toluene 35.4%, and remaining species 42%. The mean yearly concentrations of toluene (128 and 138 ?g m?3) were 2–3 times higher than those of benzene (40 and 47

  1. Double photoionization of pyrene and other aromatic hydrocarbons

    NASA Astrophysics Data System (ADS)

    Wehlitz, R.; Hartman, T.

    2014-04-01

    We have measured the ratio of doubly to singly charged parent ions of pyrene, an aromatic hydrocarbon, for photon energies ranging from threshold to the carbon K edge. Monochromatized synchrotron radiation of the Synchrotron Radiation Center has been used in combination with an ion time-of-flight spectrometer for this investigation. We compared these results with our previous measurements on benzene, coronene and pyrrole. We will discuss differences and similarities in the double photoionization for these aromatic hydrocarbons.

  2. Polycyclic aromatic hydrocarbons in the soils of Moscow

    NASA Astrophysics Data System (ADS)

    Belinskaya, E. A.; Zykova, G. V.; Semenov, S. Yu.; Finakov, G. G.

    2015-06-01

    The contents of polycyclic aromatic hydrocarbons (PAHs) in soil samples taken in the city of Moscow have been determined. A sixfold excess of the maximum permissible concentration (MPC) for benzo[ a]pyrene has been found in 66% of the studied samples; an excess of the European standard for benzo[ a]pyrene has been observed in 31% of the samples. The found weight fraction of benzo[ a]pyrene in soil samples varies in the range of 10-740 ?g/kg. The content of the ecotoxicant in the soil increases from west to east. The total concentrations of 10 indicative PAH compounds in the soils of Moscow are usually lower than the European standard. An excess of the European standard by 2-6 times has been noted in the Southeastern, Eastern, and Central administrative districts of Moscow, with separate sites of high contamination up to 6118 ?g/kg.

  3. Mechanism of aromatic hydrocarbon formation in FCC naphtha

    SciTech Connect

    Mota, C.J.A.; Rawet, R. [Petrobras-Cenpes, Rio de Janeiro (Brazil)

    1995-12-01

    A microactivity test study of the FCC naphtha composition at increasing conversions was carried out. At low conversions (ca. 10--20%), the naphtha is rich in olefinic and aromatic hydrocarbons. As the conversion increases, the composition changes dramatically. The olefins initially increase and then decrease sharply. The paraffins increase continually, and the aromatics initially decrease and then increase slightly. The naphthenics remain constant in the conversion range studied. These results indicate that, at low conversions, the aromatics in the gasoline are mainly formed by dealkylation of heavy aromatic molecules present in the feed. At higher conversions, however, the aromatics in the naphtha are mainly formed by cyclization followed by hydrogen transfer of the olefins formed during cracking. This reaction also increases the relative concentration of paraffinic hydrocarbons. The distribution of C9 aromatics showed that, as the conversion increases, there occurs an isomerization of the alkyl chain, to increase the branching of the ring.

  4. Polycyclic aromatic hydrocarbons and childhood asthma.

    PubMed

    Karimi, Parisa; Peters, Kamau O; Bidad, Katayoon; Strickland, Paul T

    2015-02-01

    Asthma is the most common chronic illness in children living in developed countries and the leading cause of childhood hospitalization and school absenteeism. Prevalence rates of asthma are increasing and show disparities across gender, geographic regions, and ethnic/racial groups. Common risk factors for developing childhood asthma include exposure to tobacco smoke, previous allergic reactions, a family history of asthma, allergic rhinitis or eczema, living in an urban environment, obesity and lack of physical exercise, severe lower respiratory tract infections, and male gender. Asthma exacerbation in children can be triggered by a variety of factors, including allergens (e.g., pollen, dust mites, and animal dander), viral and bacterial infections, exercise, and exposure to airway irritants. Recent studies have shown that exposure to polycyclic aromatic hydrocarbons (PAHs), a major component of fine particulate matter from combustion sources, is also associated with onset of asthma, and increasing asthmatic symptoms. In this paper, we review sources of childhood PAH exposure and the association between airborne PAH exposure and childhood asthma prevalence and exacerbation. PMID:25600297

  5. Aliphatic and aromatic hydrocarbons in coastal caspian Sea sediments

    Microsoft Academic Search

    Imma Tolosa; Stephen de Mora; Mohammad Reza Sheikholeslami; Jean-Pierre Villeneuve; Jean Bartocci; Chantal Cattini

    2004-01-01

    This investigation represents the first extensive study of the spatial distribution and sources of aliphatic (n-alkanes and unresolved complex mixture of fossil hydrocarbons) and polycyclic aromatic hydrocarbons (PAHs) in coastal sediments from the Caspian Sea. PAH concentrations, n-alkanes and biomarker profiles all suggested that there was limited petrogenic contamination in the shallow North Caspian Sea sediments, which are coarse with

  6. Investigation of polycyclic aromatic hydrocarbons from coal gasification.

    PubMed

    Zhou, Hong-cang; Jin, Bao-sheng; Zhong, Zhao-ping; Huang, Ya-ji; Xiao, Rui; Li, Da-ji

    2005-01-01

    The hazardous organic pollutants generated from coal gasification, such as polycyclic aromatic hydrocarbons(PAHs), are highly mutagenic and carcinogenic. More researchers have paid particular attention to them. Using air and steam as gasification medium, the experiments of three kinds of coals were carried out in a bench-scale atmospheric fluidized bed gasifier. The contents of the 16 PAHs specified by US EPA in raw coal, slag, bag house coke, cyclone coke and gas were measured by HPLC to study the contents of PAHs in raw coal and the effects of the inherent characters of coals on the formation and release of PAHs in coal gasification. The experimental results showed that the distributions of PAHs in the gasified products are similar to raw coals and the total-PAHs content in coal gasification is higher than in raw coal(except Coal C). The total-PAHs contents increase and then decrease with the rise of fixed carbon and sulfur of coal while there has an opposite variation when volatile matters content increase. The quantities of PAHs reduce with the increase of ash content or the drop of heating value during coal gasification. PMID:15900777

  7. Polycyclic Aromatic Hydrocarbon Emission within Ly? Blobs

    NASA Astrophysics Data System (ADS)

    Colbert, James W.; Scarlata, Claudia; Teplitz, Harry; Francis, Paul; Palunas, Povilas; Williger, Gerard M.; Woodgate, Bruce

    2011-02-01

    We present Spitzer observations of Ly? blobs (LABs) at z = 2.38-3.09. The mid-infrared ratios (4.5 ?m/8 ?m and 8 ?m/24 ?m) indicate that ~60% of LAB infrared counterparts are cool, consistent with their infrared output being dominated by star formation and not active galactic nuclei (AGNs). The rest have a substantial hot dust component that one would expect from an AGN or an extreme starburst. Comparing the mid-infrared to submillimeter fluxes (~850 ?m or rest-frame far-infrared) also indicates that a large percentage (~2/3) of the LAB counterparts have total bolometric energy output dominated by star formation, although the number of sources with submillimeter detections or meaningful upper limits remains small (~10). We obtained Infrared Spectrograph (IRS) spectra of six infrared-bright sources associated with LABs. Four of these sources have measurable polycyclic aromatic hydrocarbon (PAH) emission features, indicative of significant star formation, while the remaining two show a featureless continuum, indicative of infrared energy output completely dominated by an AGN. Two of the counterparts with PAHs are mixed sources, with PAH line-to-continuum ratios and PAH equivalent widths indicative of large energy contributions from both star formation and AGN. Most of the LAB infrared counterparts have large stellar masses, around 1011 M sun. There is a weak trend of mass upper limit with the Ly? luminosity of the host blob, particularly after the most likely AGN contaminants are removed. The range in likely energy sources for the LABs found in this and previous studies suggests that there is no single source of power that is producing all the known LABs.

  8. Formation mechanism for polycyclic aromatic hydrocarbons in methane flames

    NASA Astrophysics Data System (ADS)

    Siegmann, K.; Sattler, K.

    2000-01-01

    A laminar diffusion flame of methane was investigated using time-of-flight mass spectroscopy with two-photon UV laser ionization. Benzenoid polycyclic aromatic hydrocarbons (PAHs) up to 788 amu (C64H20) were detected in the combustion gases. Only the most compact PAHs are formed in the flame. The observed groups of PAH peaks with 24 amu spacings belong to PAHs with constant hydrogen content and are separated by 26 amu gaps. The sequences of PAH peaks with 24 amu spacing are explained by a repetitive bay closure mechanism. The first PAH of a constant H-sequence is proposed to form by a dimerization process. The PAHs observed can be arranged in a repetitive pattern in Dias's formula periodic system.

  9. Polycyclic aromatic hydrocarbons in human fat and liver

    SciTech Connect

    Obana, H.; Hori, S.; Kashimoto, T.; Kunita, N.

    1981-07-01

    Nine polycyclic aromatic hydrocarbons (PAH) were determined in human fat and liver by high pressure liquid column chromatography without complex pretreatment prior to analysis. Fat and liver tissue were obtained from autopsies. Smoking habits, occupations, and residence of the persons were unknown. The tissues were free from cancer. Differences of sex and age did not affect PAH content in the tissues. Pyrene averaged 1100 ppT in the fat and 380 ppT in the liver. The next highest level was that of anthracene (260 ppT in the fat and 170 ppT in the liver). The known carcinogens, benzanthracene and dibenzanthracene, were not detected in either tissue, but benzo(a)pyrene was present at a rather low level (20 ppT in both tissues). (RJC)

  10. POLYCYCLIC AROMATIC HYDROCARBONS AND THE ORIGIN OF TIN DEPOSITS IN THE SOVIET MARITIME PROVINCE

    Microsoft Academic Search

    M. A. Favorskaya; V. N. Florovskaya; A. I. Ogloblina; Yu. I. Pikovskiy; M. Ye. Ramenskaya

    1986-01-01

    In recent years, interest has grown in the role of carbon compounds, including polycyclic aromatic hydrocarbons (PAH), in endogenous processes. The body of data on the contents of such compounds in rocks, ores, and minerals is extensive. Evidence has been given for a plutonic or mantle origin for certain carbon compounds. Some groups of these compounds have been considered as

  11. Distribution of polycyclic aromatic hydrocarbons in subcellular root tissues of ryegrass (Lolium multiflorum Lam.)

    Microsoft Academic Search

    Fuxing Kang; Dongsheng Chen; Yanzheng Gao; Yi Zhang

    2010-01-01

    BACKGROUND: Because of the increasing quantity and high toxicity to humans of polycyclic aromatic hydrocarbons (PAHs) in the environment, several bioremediation mechanisms and protocols have been investigated to restore PAH-contaminated sites. The transport of organic contaminants among plant cells via tissues and their partition in roots, stalks, and leaves resulting from transpiration and lipid content have been extensively investigated. However,

  12. Polycyclic aromatic hydrocarbon (PAH)-phase associations in Washington coastal sediment

    Microsoft Academic Search

    Fredrick G. Prahl; Roy Carpenter

    1983-01-01

    Polycyclic aromatic (PAH) and aliphatic hydrocarbon compositions, organic carbon, nitrogen and lignin contents were determined in whole, unfractionated sediment from the Washington continental shelf and in discrete sediment fractions separated by particle size and density. At least 20 to 25% of perylene and PAH derived from pyrolytic processes and 50% of the retene measured in whole sediment are contained within

  13. Hydrophobicity of Siloxane Surfaces in Smectites as Revealed by Aromatic Hydrocarbon Adsorption from Water

    Microsoft Academic Search

    W. F. Jaynes; S. A. BOYD

    1991-01-01

    The nature of the siloxane surface in smectites was investigated by measuring the adsorption of aromatic hydrocarbons from water by organo-clays. The organo-clays were prepared by replacing the hydrophilic, inorganic exchange cations of a series of smectites with the small, hydrophobic organic cation, trimethylphenylammonium (TMPA). Smectites with a range in charge densities were used that resulted in different TMPA contents

  14. Determination of polycyclic aromatic hydrocarbons (PAHs) in commonly consumed Nigerian smoked\\/grilled fish and meat

    Microsoft Academic Search

    V. O. E. Akpambang; G. Purcaro; L. Lajide; I. A. Amoo; L. S. Conte; S. Moret

    2009-01-01

    Smoking and\\/or grilling, when carried out with traditional methods involving direct contact with wood combustion fumes, is responsible for high contamination levels with carcinogenic polycyclic aromatic hydrocarbons (PAHs). The aim of this work was to investigate the PAH content of different smoked or grilled meat and fish products commonly consumed in Nigeria. A rapid method involving microwave-assisted saponification and simultaneous

  15. In vitro toxicity of polycyclic aromatic hydrocarbons and halogenated aromatic hydrocarbons to cetacean cells and tissues

    SciTech Connect

    Carvan, M.J. III.

    1993-01-01

    Cetaceans bioaccumulate high aromatic hydrocarbon tissue residues, and elevated levels of PCB residues in tissues are proposed to have occurred concurrently with recent epizootic deaths of dolphins. The objectives of this study were: (1) to develop and characterize an epithelial cell line derived from dolphin tissues, (2) to investigate the effects of hydrocarbon pollutants on those cells, and (3) to analyze the toxicity of hydrocarbon pollutants on cetacean tissues in vitro. An epithelial cell line, Carvan dolphin kidney (CDK), isolated from a spontaneously aborted female bottlenose dolphin, Tursiops truncatus, grew rapidly. These cells were neither transformed nor immortal. Velocity sedimentation analysis showed CDK cells contained nuclear aryl hydrocarbon receptor, suggestive of cytochrome P450 inducibility. BaP inhibited mitosis in CDK cells in a dose-dependent manner. Data indicate that CDK cells metabolize BaP, that BaP metabolites bind to cellular DNA initiating unscheduled DNA synthesis, and that the inhibition of cytochrome P450 metabolism decrease the BaP-associated inhibition of mitosis in dolphin cells. The data also suggest that TCDD acts synergistically to increase the levels of DNA damage by the procarcinogen BaP. Cetacean liver microsomes was isolated and evaluated for the presence of cytochrome P450 proteins by SDS-PAGE, apparent minimum molecular weight determination, and immunoblot analysis. P450 activity was induced in cetacean tissue samples and CDK cells by exposure in vitro to one of several cytochrome P450-inducing chemicals. The data suggest that cetacean tissues and cells can be utilized to study the in vitro induction of cytochrome P450, resultant metabolism of xenobiotic contaminants, and the subsequent cellular and molecular responses. However, the identity of specific P450 isozymes involved in this process will remain undetermined until monoclonal antibodies that recognize cetacean P450s can be generated.

  16. Astrochemical studies of polycyclic aromatic hydrocarbons and fullerenes

    NASA Astrophysics Data System (ADS)

    Elsila, Jamie Elizabeth

    Microprobe laser-desorption, laser-ionization mass spectrometry (mL 2 MS) is used to measure the spatial and chemical distributions of polycyclic aromatic hydrocarbons (PAHs) and related carbonaceous compounds in a variety of real and laboratory-simulated extraterrestrial samples. The combination of this sensitive microanalytical technique with this interesting group of compounds provides novel information about the chemical history of the solar system, the potential for the formation of life on other worlds, and the rich chemistry that exists in interstellar space. This dissertation focuses first on properties of the mL 2 MS technique. Factors affecting its quantitative abilities were determined. It is also shown that mL 2 MS samples the free organic material in meteorites, rather than the macromolecular material. Additionally, mL 2 MS was modified to detect the fullerene molecule C 60 in toluene solutions but proved incapable of detecting aggregated C 60 . The focus of this thesis then turns to the analysis of laboratory simulations and field samples of astrochemical interest: (1) The spatial distribution and degree of alkylation of PAHs were measured in carbonaceous chondrites. The results suggest that meteoritic PAHs resulted from a common pool of compounds prior to meteoritic parent-body formation. These compounds may then have been separated chromatographically by parent-body aqueous exposure or lost by volatilization during thermal metamorphism. (2) C 60 was detected in samples from three terrestrial impact craters (Sudbury, Gardnos, and Ries) using surface-enhanced laser desorption/ionization. (3) Energetic processing of interstellar ice analogs by ultraviolet radiation or high-energy proton irradiation caused the addition of a variety of side groups to the PAH coronene, as detected by mL 2 MS. Formation of new C-C, C-O, and C-N bonds was observed. (4) Simulations of the atmospheric chemistry of Titan showed that PAHs and nitrogen-containing aromatics may be formed in this environment. The aromatic content and extent of aromatic nitrogen incorporation detected by mL 2 MS increased in tholins formed at lower pressures. (5) mL 2 MS and gas chromatography-mass spectrometry (GC-MS) analysis of Siberian hydrothermal samples revealed the presence of PAHs and aliphatic hydrocarbons, with abundance and distribution varying among the sampling sites. These compounds may be of abiotic or biologic origin.

  17. Aromaticity of Polycyclic Conjugated Hydrocarbons Milan Randic*

    E-print Network

    Ferreira, Márcia M. C.

    Heisenberg). Supek introduced him to the book by Linus Pauling, The Nature of the Chemical Bond for Benzenoid Hydrocarbons 3490 1. Pauling-Wheland Valence Bond Approach 3490 2. Pauling-Wheland Resonance

  18. Biodegradation aspects of Polycyclic Aromatic Hydrocarbons (PAHs): A review

    Microsoft Academic Search

    A. K. Haritash; C. P. Kaushik

    2009-01-01

    PAHs are aromatic hydrocarbons with two or more fused benzene rings with natural as well as anthropogenic sources. They are widely distributed environmental contaminants that have detrimental biological effects, toxicity, mutagenecity and carcinogenicity. Due to their ubiquitous occurrence, recalcitrance, bioaccumulation potential and carcinogenic activity, the PAHs have gathered significant environmental concern. Although PAH may undergo adsorption, volatilization, photolysis, and chemical

  19. Polycyclic Aromatic Hydrocarbons in Maternal and Cord Blood Plasma

    Microsoft Academic Search

    Paula G. Radmacher; Stephen W. Looney; Steven R. Myers

    2010-01-01

    Polycyclic aromatic hydrocarbons (PAH) come from incomplete combustion of organic materials, including tobacco smoke. Some PAH are known to be mutagenic and carcinogenic and of concern for the fetus when women smoke during pregnancy. Known consequences of smoking during pregnancy include low birth weight (LBW) and preterm (PT) delivery. This study was designed to measure concentrations of 3 PAH: anthracene

  20. Polycyclic aromatic hydrocarbons in fuel-oil contaminated soils, Antarctica

    Microsoft Academic Search

    Jackie Aislabie; Megan Balks; Norma Astori; Gavin Stevenson; Robert Symons

    1999-01-01

    Where fuel oil spills have occurred on Antarctic soils polycyclic aromatic hydrocarbons (PAH) may accumulate. Surface and subsurface soil samples were collected from fuel spill sites up to 30 years old, and from nearby control sites, and analysed for the 16 PAHs on the USEPA priority pollutants list, as well as for two methyl substituted naphthalenes, 1-methylnaphthalene and 2-methylnaphthalene. PAH

  1. Polycyclic aromatic hydrocarbons in Estonian soil: contamination and profiles

    Microsoft Academic Search

    M Trapido

    1999-01-01

    The distribution and accumulation of polycyclic aromatic hydrocarbons (PAH) in soil as well as PAH profiles have been investigated in areas with different anthropogenic pollution such as the city of Tallinn, the towns of Pärnu and Kohtla-Järve and some rural areas. PAH were identified in 147 soil samples (0–10 cm upper layer) collected in September 1996. The typical ? PAH

  2. AGRONOMIC OPTIMIZATION FOR PHYTOREMEDIATION OF POLYCYCLIC AROMATIC HYDROCARBONS

    EPA Science Inventory

    Phytoremediation is a low-cost method of using plants to degrade, volatilize or sequester organic and metal pollutants that has been used in efforts to remediate sites contaminated with polycyclic aromatic hydrocarbon (PAH) refinery wastes. Non-native plant species aggressivel...

  3. Atmospheric polycyclic aromatic hydrocarbons: Source attribution, emission factors and regulation

    Microsoft Academic Search

    Khaiwal Ravindra; Ranjeet Sokhi; René Van Grieken

    2008-01-01

    There is an increasing concern about the occurrence of polycyclic aromatic hydrocarbons (PAHs) in the environment as they are ubiquitous in ambient air and some of them are among the strongest known carcinogens. PAHs and their derivatives are produced by the incomplete combustion of organic material arising, partly, from natural combustion such as forest and volcanic eruption, but with the

  4. Structure-biodegradability relationships of polycyclic aromatic hydrocarbons in soil

    Microsoft Academic Search

    Ingeborg D. Bossert; Richard Bartha

    1986-01-01

    The potential of some polycyclic aromatic hydrocarbons (PAH) to be metabolized to mutagenic and\\/or carcinogenic compounds (Cerniglia 1984, Gibson & Subramanian 1984) has caused concern for environmental pollution by this class of residues. In industrialized countries, pollution by PAH is primarily associated with the processing, combustion and disposal of fossil fuels (Bartha & Bossert 1984, Hites& LaFlamme 1977), but low

  5. Laboratory Infrared Spectroscopy of Cationic Polycyclic Aromatic Hydrocarbon Molecules

    Microsoft Academic Search

    Jos Oomens; A. G. G. M. Tielens; Boris G. Sartakov; Gert von Helden; Gerard Meijer

    2003-01-01

    Infrared spectroscopy of a variety of interstellar sources shows strong mid-IR emission bands, which are generally attributed to emission from highly vibrationally excited polycyclic aromatic hydrocarbon molecules (PAHs) in the neutral and, particularly, cationic states. Over the past decade, various experimental methods have been developed to record the infrared spectra of cationic PAHs in the laboratory. In this paper, we

  6. Groundwater risk assessment for a Polycyclic Aromatic Hydrocarbons (PAH) contaminated

    E-print Network

    Paris-Sud XI, Université de

    2001-53 Groundwater risk assessment for a Polycyclic Aromatic Hydrocarbons (PAH) contaminated site to simulate a contamination of soils and groundwaters by PAH at a disused coke plant site were compared applying a risk assessment approach to contaminated sites, of primary importance is the evaluation

  7. Occurrence of polycyclic aromatic hydrocarbons in municipal sewage sludge ashes

    Microsoft Academic Search

    Patricia C. Wszolek; Timothy Wachs

    1982-01-01

    Sludge ash residues from four cities that incinerate municipal sewage sludge were analyzed for isolated polycyclic aromatic hydrocarbons. Total amounts of PAHs in the ashes were in the range of 0.1–1µg\\/g. The ash containing the highest amount also exhibited the greatest variety of PAHs.

  8. CHILDREN'S AGGREGATE EXPOSURE TO POLYCYCLIC AROMATIC HYDROCARBONS (PAHS)

    EPA Science Inventory

    Polycyclic aromatic hydrocarbons (PAHs) have been frequently detected at children's homes and day care centers and may pose health concerns due to their carcinogenicity. Most PAHs have been persistent indoors and outdoors, therefore, children may be exposed to chronic low level...

  9. Interactions of polyhalogeneted aromatic hydrocarbons with thyroid hormone metabolism

    Microsoft Academic Search

    A. G. Schuur

    1998-01-01

    This thesis deals with the possible interactions of polyhalogenated aromatic hydrocarbons and\\/or their metabolites with thyroid hormone metabolism. This chapter summarizes firstly the effects of thyroid hormone on the induction of biotransformation enzymes by PHAHs. Secondly, the results on the inhibition of thyroid hormone sulfation by hydroxylated metabolites of PHAH are summarized. Some conclusions and remarks on the overall implications

  10. ENVIRONMENTAL CARCINOGENIC POLYCYCLIC AROMATIC HYDROCARBONS: PHOTOCHEMISTRY AND PHOTOTOXICITY

    Microsoft Academic Search

    Hongtao Yu

    2002-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are a class of environmental contaminants that has long been of interest in the fields of organic chemistry, theoretical chemistry, physical chemistry, environmental science, toxicology, cancer research, and energy sciences. Concerning environmental science and cancer research, majority of the research has focused on the occurrence, environmental fate, degradation\\/remediation, chemical transformation, genotoxicity, metabolism and metabolic activation, DNA

  11. Enhanced Bioremediation of Polycyclic Aromatic Hydrocarbons by Environmentally Friendly Techniques

    Microsoft Academic Search

    Huey-Min Hwang; Xiaoke Hu; Xueheng Zhao

    2007-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are recognized as a worldwide environmental contamination problem because of their intrinsic chemical stability, high resistance to various transformation processes, and toxicity property. Because of the wide distribution of the PAHs in the environment, human exposure to the PAHs is likely to occur from dermal contact, ingestion of particles, inhalation of airborne dust, or bioaccumulation in

  12. UV Irradiation of Polycyclic Aromatic Hydrocarbons in Ices

    E-print Network

    . Clemett,3 Richard N. Zare3 Polycyclic aromatic hydrocarbons (PAHs) in water ice were exposed to ultra with laboratory stud- ies of realistic interstellar analog materials, is a powerful means for identifying abundant and widespread class of carbon-car- rying gaseous species is believed to be PAHs (3­5). In dense

  13. Effect of bioremediation on polycyclic aromatic hydrocarbon residues in soil

    Microsoft Academic Search

    Xiaoping Wang; Xiaobing Yu; Richard Bartha

    1990-01-01

    Soil contamination (60 mg\\/g of soil) by a diesel oil (DO) spill was simulated in outdoor lysimeter units and the effect of bioremediation treatment consisting of liming, fertilization, and tilling on the persistence of polycyclic aromatic hydrocarbon (PAH) components of DO was measured. After solvent extraction from soil and class separation on silica gel, PAH components were identified and partially

  14. Thermal neutron cross-section libraries for aromatic hydrocarbons

    Microsoft Academic Search

    F. Cantargi; J. R. Granada

    2010-01-01

    Solid phases of aromatic hydrocarbons, such as benzene, toluene, mesitylene and a 3:2 mixture by volume of mesitylene and toluene, were studied as potential moderator materials for a cold neutron source. Existing information on the (lattice) translational and rotational modes of the different molecular species was used to produce generalized frequency spectra; the latter included the internal vibrational modes which

  15. Dermal Exposure to Polycyclic Aromatic Hydrocarbons among Road Pavers

    Microsoft Academic Search

    VIRPI VAANANEN; MERVI HAMEILA; PENTTI KALLIOKOSKI; ELINA NYKYRI; PIRJO HEIKKILA

    2005-01-01

    Objectives: Dermal exposure to polycyclic aromatic hydrocarbons (PAHs) and the role of an industrial by-product, coal fly ash, on workers' PAH exposure were investigated during stone mastic asphalt (SMA) paving and remixing. Methods: PAH exposure was measured at eight sites during the laying of SMA containing coal fly ash or limestone (conventional SMA) as the filler. Six of the surveys

  16. Modeling the biodegradability and physicochemical properties of polycyclic aromatic hydrocarbons 

    E-print Network

    Dimitriou-Christidis, Petros

    2006-10-30

    OF BINARY AND TERNARY MIXTURES OF POLYCYCLIC AROMATIC HYDROCARBONS ..................................... 80 Overview.............................................................................................80 Introduction... of binary (a, b, and c) and ternary (d) mixtures of 2MPHE, FLA, and PYR...........................................................101 xi LIST OF TABLES TABLE 1.1 PAHs used in the four experiments discussed in this dissertation...

  17. Emission of polycyclic aromatic hydrocarbons from animal carcass incinerators

    Microsoft Academic Search

    Shui-Jen Chen; Lien-Te Hsieh; Shui-Chi Chiu

    2003-01-01

    This study investigated two batch-type animal carcass waste incinerators, one in a hog farm (HOWI) and the other in a livestock disease control centre (LIWI). Additionally, a medical waste incinerator (MEWI) with a fixed grate for the disposal of biological medical waste was also examined. A GC\\/MS technique was applied to analyze the concentrations of 21 polycyclic aromatic hydrocarbons (PAHs)

  18. Ambient aromatic hydrocarbon measurements at Welgegund, South Africa

    NASA Astrophysics Data System (ADS)

    Jaars, K.; Beukes, J. P.; van Zyl, P. G.; Venter, A. D.; Josipovic, M.; Pienaar, J. J.; Vakkari, V.; Aaltonen, H.; Laakso, H.; Kulmala, M.; Tiitta, P.; Guenther, A.; Hellén, H.; Laakso, L.; Hakola, H.

    2014-07-01

    Aromatic hydrocarbons are associated with direct adverse human health effects and can have negative impacts on ecosystems due to their toxicity, as well as indirect negative effects through the formation of tropospheric ozone and secondary organic aerosol, which affect human health, crop production and regional climate. Measurements of aromatic hydrocarbons were conducted at the Welgegund measurement station (South Africa), which is considered to be a regionally representative background site. However, the site is occasionally impacted by plumes from major anthropogenic source regions in the interior of South Africa, which include the western Bushveld Igneous Complex (e.g. platinum, base metal and ferrochrome smelters), the eastern Bushveld Igneous Complex (platinum and ferrochrome smelters), the Johannesburg-Pretoria metropolitan conurbation (> 10 million people), the Vaal Triangle (e.g. petrochemical and pyrometallurgical industries), the Mpumalanga Highveld (e.g. coal-fired power plants and petrochemical industry) and also a region of anticyclonic recirculation of air mass over the interior of South Africa. The aromatic hydrocarbon measurements were conducted with an automated sampler on Tenax-TA and Carbopack-B adsorbent tubes with heated inlet for 1 year. Samples were collected twice a week for 2 h during daytime and 2 h during night-time. A thermal desorption unit, connected to a gas chromatograph and a mass selective detector was used for sample preparation and analysis. Results indicated that the monthly median (mean) total aromatic hydrocarbon concentrations ranged between 0.01 (0.011) and 3.1 (3.2) ppb. Benzene levels did not exceed the local air quality standard limit, i.e. annual mean of 1.6 ppb. Toluene was the most abundant compound, with an annual median (mean) concentration of 0.63 (0.89) ppb. No statistically significant differences in the concentrations measured during daytime and night-time were found, and no distinct seasonal patterns were observed. Air mass back trajectory analysis indicated that the lack of seasonal cycles could be attributed to patterns determining the origin of the air masses sampled. Aromatic hydrocarbon concentrations were in general significantly higher in air masses that passed over anthropogenically impacted regions. Inter-compound correlations and ratios gave some indications of the possible sources of the different aromatic hydrocarbons in the source regions defined in the paper. The highest contribution of aromatic hydrocarbon concentrations to ozone formation potential was also observed in plumes passing over anthropogenically impacted regions.

  19. Pollution patterns of polycyclic aromatic hydrocarbons in tobacco smoke.

    PubMed

    Lu, Hao; Zhu, Lizhong

    2007-01-10

    Concentrations of polycyclic aromatic hydrocarbons (PAHs) in tobacco smoke of 12 commercial brand cigarettes were determined in a simulated chamber of 20.25 m3 in size. The total concentrations of 17 PAHs (summation operatorPAHs) in the chamber were 3500 and 1152 ng/m3 in vapor phase and particulate phase, respectively. In vapor phase, the yield of naphthalene (NA) appeared to be the most abundant (2462 ng/cig) followed by fluorene (FLUOR) and acenaphthylene (ACY), while the yield of benzo[ghi]perylene (BP) was the most abundant (259.7 ng/cig) in particulate phase followed by phenanthrene (PHEN) and FLUOR. The proportion of PAHs in particulate phase increased with increasing molecular weight. PAHs with two to six rings accounted for 40.2%, 35.3%, 11.7%, 7.6%, 5.2% of summation operatorPAHs, respectively. There was no obvious correlation between PAHs, benzo[a]pyrene (BaP) concentrations in tobacco smoke and smoking tar contents, nicotine contents. With the source fingerprint of PAHs in tobacco smoke, NA could be regarded as the marker of tobacco smoke source because of its largest contribution to summation operatorPAHs (40.2%), followed by FLUOR (12.7%) and ACY (9.8%). Further study indicated that more than 80% of BaP in indoor air of resident homes in Hangzhou was from tobacco smoke. PMID:16839683

  20. Aromatic and polycyclic aromatic hydrocarbon formation in a laminar premixed n-butane flame

    SciTech Connect

    Marinov, N.M.; Pitz, W.J.; Westbrook, C.K. [Lawrence Livermore National Lab., CA (United States)] [Lawrence Livermore National Lab., CA (United States); Vincitore, A.M.; Castaldi, M.J.; Senkan, S.M. [Univ. of California, Los Angeles, CA (United States)] [Univ. of California, Los Angeles, CA (United States); Melius, C.F. [Sandia National Labs., Livermore, CA (United States)] [Sandia National Labs., Livermore, CA (United States)

    1998-07-01

    Experimental and detailed chemical kinetic modeling work has been performed to investigate aromatic and polycyclic aromatic hydrocarbon (PAH) formation pathways in a premixed, rich, sooting, n-butane-oxygen-argon burner stabilized flame. An atmospheric pressure, laminar flat flame operated at an equivalence ratio of 2.6 was used to acquire experimental data for model validation. Gas composition analysis was conducted by an on-line gas chromatograph/mass spectrometer technique. Measurements were made in the main reaction and post-reaction zones for a number of low molecular weight species, aliphatics, aromatics, and polycyclic aromatic hydrocarbons (PAHs) ranging from two to five-fused aromatic rings. Reaction flux and sensitivity analysis were used to help identify the important reaction sequences leading to aromatic and PAH growth and destruction in the n-butane flame. Reaction flux analysis showed the propargyl recombination reaction was the dominant pathway to benzene formation. The consumption of propargyl by H atoms was shown to limit propargyl, benzene, and naphthalene formation in flames as exhibited by the large negative sensitivity coefficients. Naphthalene and phenanthrene production was shown to be plausibly formed through reactions involving resonantly stabilized cyclopentadienyl and indenyl radicals. Many of the low molecular weight aliphatics, combustion by-products, aromatics, branched aromatics, and PAHs were fairly well simulated by the model. Additional work is required to understand the formation mechanisms of phenyl acetylene, pyrene, and fluoranthene in the n-butane flame. 73 refs.

  1. Biodegradation of aliphatic vs. aromatic hydrocarbons in fertilized arctic soils

    USGS Publications Warehouse

    Braddock, J.F.

    1999-01-01

    A study was carried out to test a simple bioremediation treatment strategy in the Arctic and analyze the influence of fertilization the degradation of aliphatic and aromatic hydrocarbons, e.g., pristine, n-tetradecane, n-pentadecane, 2-methylnaphthalene, naphthalene, and acenaphthalene. The site was a coarse sand pad that once supported fuel storage tanks. Diesel-range organics concentrations were 250-860 mg/kg soil at the beginning of the study. Replicate field plots treated with fertilizer yielded final concentrations of 0, 50, 100, or 200 mg N/kg soil. Soil pH and soil-water potentials decreased due to fertilizer application. The addition of fertilizer considerably increased soil respiration potentials, but not the populations of microorganisms measured. Fertilizer addition also led to ??? 50% loss of measured aliphatic and aromatic hydrocarbons in surface and subsurface soils. For fertilized plots, hydrocarbon loss was not associated with the quantity of fertilizer added. Losses of aliphatic hydrocarbons were ascribed to biotic processes, while losses of aromatic hydrocarbons were due to biotic and abiotic processes.

  2. Effect of fluorine substitution on the aromaticity of polycyclic hydrocarbons.

    PubMed

    Kaipio, Mikko; Patzschke, Michael; Fliegl, Heike; Pichierri, Fabio; Sundholm, Dage

    2012-10-18

    The effect of fluorine substitution on the aromaticity of polycyclic hydrocarbons (PAH) is investigated. Magnetically induced current densities, current pathways, and current strengths, which can be used to assess molecular aromaticity, are calculated using the gauge-including magnetically induced current method (GIMIC). The degree of aromaticity of the individual rings is compared to those obtained using calculated nucleus-independent chemical shifts at the ring centers (NICS(0) and NICS(0)(zz)). Calculations of explicitly integrated current strengths for selected bonds show that the aromatic character of the investigated polycyclic hydrocarbons is weakened upon fluorination. In contrast, the NICS(0) values for the fluorinated benzenes increase noteworthy upon fluorination, predicting a strong strengthening of the aromatic character of the arene rings. The integrated current strengths also yield explicit current pathways for the studied molecules. The current pathways of the investigated linear polyacenes, pyrene, anthanthrene, coronene, ovalene, and phenanthro-ovalene are not significantly affected by fluorination. NISC(0) and NICS(0)(zz) calculations provide contradictory degrees of aromaticity of the fused individual ring. Obtained NICS values do not correlate with the current strengths circling around the individual rings. PMID:22994485

  3. Aromatic and Polycyclic Aromatic Hydrocarbon Formation in a Laminar Premixed n-Butane Flame

    Microsoft Academic Search

    Nick M Marinov; William J Pitz; Charles K Westbrook; Antonio M Vincitore; Marco J Castaldi; Selim M Senkan; Carl F Melius

    1998-01-01

    Experimental and detailed chemical kinetic modeling work has been performed to investigate aromatic and polycyclic aromatic hydrocarbon (PAH) formation pathways in a premixed, rich, sooting, n-butane–oxygen–argon burner stabilized flame. An atmospheric pressure, laminar flat flame operated at an equivalence ratio of 2.6 was used to acquire experimental data for model validation. Gas composition analysis was conducted by an on-line gas

  4. Toxicity Analysis of Polycyclic Aromatic Hydrocarbon Mixtures 

    E-print Network

    Naspinski, Christine S.

    2010-01-16

    ............................................... 35 2-1 Variability of floor surface total PAH loadings in each location.................... 58 2-2 Seasonal variation in floor wipe samples from Azerbaijan and China ......... 59 2-3 PAH profile by number of aromatic rings in floor wipes from each..., combustion of fuels, tobacco and candles, and by use of personal care products, cleaning products, home maintenance products, and lawn and gardening equipment. Use of tap water for bathing, cooking, washing, and sanitation can release volatile...

  5. Biodegradation of Aromatic Hydrocarbons in an Extremely Acidic Environment

    PubMed Central

    Stapleton, Raymond D.; Savage, Dwayne C.; Sayler, Gary S.; Stacey, Gary

    1998-01-01

    The potential for biodegradation of aromatic hydrocarbons was evaluated in soil samples recovered along gradients of both contaminant levels and pH values existing downstream of a long-term coal pile storage basin. pH values for areas greatly impacted by runoff from the storage basin were 2.0. Even at such a reduced pH, the indigenous microbial community was metabolically active, showing the ability to oxidize more than 40% of the parent hydrocarbons, naphthalene and toluene, to carbon dioxide and water. Treatment of the soil samples with cycloheximide inhibited mineralization of the aromatic substrates. DNA hybridization analysis indicated that whole-community nucleic acids recovered from these samples did not hybridize with genes, such as nahA, nahG, nahH, todC1C2, and tomA, that encode common enzymes from neutrophilic bacteria. Since these data suggested that the degradation of aromatic compounds may involve a microbial consortium instead of individual acidophilic bacteria, experiments using microorganisms isolated from these samples were initiated. While no defined mixed cultures were able to evolve 14CO2 from labeled substrates in these mineralization experiments, an undefined mixed culture including a fungus, a yeast, and several bacteria successfully metabolized approximately 27% of supplied naphthalene after 1 week. This study shows that biodegradation of aromatic hydrocarbons can occur in environments with extremely low pH values. PMID:9797263

  6. Occupational exposure to Polycyclic Aromatic Hydrocarbons in wood dust

    NASA Astrophysics Data System (ADS)

    Huynh, C. K.; Schüpfer, P.; Boiteux, P.

    2009-02-01

    Sino-nasal cancer (SNC) represents approximately 3% of Oto-Rhino-Laryngology (ORL) cancers. Adenocarcinoma SNC is an acknowledged occupational disease affecting certain specialized workers such as joiners and cabinetmakers. The high proportion of woodworkers contracting a SNC, subjected to an estimated risk 50 to 100 times higher than that affecting the general population, has suggested various study paths to possible causes such as tannin in hardwood, formaldehyde in plywood and benzo(a)pyrene produced by wood when overheated by cutting tools. It is acknowledged that tannin does not cause cancer to workers exposed to tea dust. Apart from being an irritant, formaldehyde is also classified as carcinogenic. The path involving carcinogenic Polycyclic Aromatic Hydrocarbons (PAHs) emitted by overheated wood is attractive. In this study, we measured the particle size and PAHs content in dust emitted by the processing of wood in an experimental chamber, and in field situation. Quantification of 16 PAHs is carried out by capillary GC-ion trap Mass Spectrometric analysis (GC-MS). The materials tested are rough fir tree, oak, impregnated polyurethane (PU) oak. The wood dust contains carcinogenic PAHs at the level of ?g.g-1 or ppm. During sanding operations, the PU varnish-impregnated wood produces 100 times more PAHs in dust than the unfinished wood.

  7. Polycyclic aromatic hydrocarbons and esophageal squamous cell carcinoma.

    PubMed

    Roshandel, Gholamreza; Semnani, Shahryar; Malekzadeh, Reza; Dawsey, Sanford M

    2012-11-01

    Esophageal cancer (EC) is the 8th most common cancer and the 6th most frequent cause of cancer mortality worldwide. Esophageal squamous cell carcinoma (ESCC) is the most common type of EC. Exposure to polycyclic aromatic hydrocarbons (PAHs) has been suggested as a risk factor for developing ESCC. In this paper we will review different aspects of the relationship between PAH exposure and ESCC. PAHs are a group of compounds that are formed by incomplete combustion of organic matter. Studies in humans have shown an association between PAH exposure and development of ESCC in many populations. The results of a recent case-control study in a high risk population in northeastern Iran showed a dramatic dose-response relationship between PAH content in non-tumor esophageal tissue (the target tissue for esophageal carcinogenesis) and ESCC case status, consistent with a causal role for PAH exposure in the pathogenesis of ESCC.  Identifying the main sources of exposure to PAHs may be the first and most important step in designing appropriate PAH-reduction interventions for controlling ESCC, especially in high risk areas. Coal smoke and drinking mate have been suggested as important modifiable sources of PAH exposure in China and Brazil, respectively. But the primary source of exposure to PAHs in other high risk areas for ESCC, such as northeastern Iran, has not yet been identified. Thus, environmental studies to determining important sources of PAH exposure should be considered as a high priority in future research projects in these areas. PMID:23102250

  8. Distribution of polycyclic aromatic hydrocarbons in lime spray dryer ash

    SciTech Connect

    Ping Sun; Panuwat Taerakul; Linda K. Weavers; Harold W. Walker [Ohio State University, Columbus, OH (United States). Department of Civil and Environmental Engineering and Geodetic Science

    2005-10-01

    Four lime spray dryer (LSD) ash samples were collected from a spreader stoker boiler and measured for their concentrations of 16 U.S. EPA specified polycyclic aromatic hydrocarbons (PAHs). Results showed that the total measured PAH concentration correlated with the organic carbon content of the LSD ash. Each LSD ash sample was then separated using a 140 mesh sieve into two fractions: a carbon-enriched fraction ({gt}140 mesh) and a lime-enriched fraction ({lt}140 mesh). Unburned carbon was further separated from the carbon-enriched fraction with a lithiumheteropolytungstate (LST) solution. PAH measurements on these different fractions showed that unburned carbon had the highest PAH concentrations followed by the carbon-enriched fraction, indicating that PAHs were primarily associated with the carbonaceous material in LSD ash. However, detectable levels of PAHs were also found in the lime-enriched fraction, suggesting that the fine spray of slaked lime may sorb PAH compounds from the flue gas in the LSD process. 37 refs., 5 figs., 4 tabs.

  9. Ambient aromatic hydrocarbon measurements at Welgegund, South Africa

    NASA Astrophysics Data System (ADS)

    Jaars, K.; Beukes, J. P.; van Zyl, P. G.; Venter, A. D.; Josipovic, M.; Pienaar, J. J.; Vakkari, V.; Aaltonen, H.; Laakso, H.; Kulmala, M.; Tiitta, P.; Guenther, A.; Hellén, H.; Laakso, L.; Hakola, H.

    2014-02-01

    Aromatic hydrocarbons are associated with direct adverse human health effects and can have negative impacts on ecosystems due to their toxicity, as well as indirect negative effects through the formation of tropospheric ozone and secondary organic aerosol that affect human health, crop production and regional climate. Measurements were conducted at the Welgegund measurement station (South Africa) that is considered to be a regionally representative background site. However, the site is occasionally impacted by plumes from major anthropogenic source regions in the interior of South Africa, which include the western Bushveld Igneous Complex (e.g. platinum, base metal and ferrochrome smelters), the eastern Bushveld Igneous Complex (platinum and ferrochrome smelters), the Johannesburg-Pretoria metropolitan conurbation (>10 million people), the Vaal Triangle (e.g. petrochemical and pyrometallurgical industries), the Mpumalanga Highveld (e.g. coal-fired power plants and petrochemical industry) and also a region of anti-cyclonic recirculation of air mass over the interior of South Africa. The aromatic hydrocarbon measurements were conducted with an automated sampler on Tenax-TA and Carbopack-B adsorbent tubes with heated inlet for one year. Samples were collected twice a week for two hours during daytime and two hours during night-time. A thermal desorption unit, connected to a gas chromatograph and a mass selective detector was used for sample preparation and analysis. Results indicated that the monthly median total aromatic hydrocarbon concentrations ranged between 0.01 to 3.1 ppb. Benzene levels did not exceed local air quality standards. Toluene was the most abundant species, with an annual median concentration of 0.63 ppb. No statistically significant differences in the concentrations measured during daytime and night-time were found and no distinct seasonal patterns were observed. Air mass back trajectory analysis proved that the lack of seasonal cycles could be attributed to patterns determining the origin of the air masses sampled. Aromatic hydrocarbon concentrations were in general significantly higher in air masses that passed over anthropocentrically impacted regions. Interspecies correlations and ratios gave some indications of the possible sources for the different aromatic hydrocarbons in the source regions defined in the paper. The highest contribution of aromatic hydrocarbon concentrations to ozone formation potential was also observed in plumes passing over anthropocentrically impacted regions.

  10. Phototransformation of polycyclic aromatic hydrocarbons into stable, mutagenic components

    SciTech Connect

    Okinaka, R.T.; Nickols, J.W.; Whaley, T.W.; Strniste, G.F.

    1983-01-01

    This report compares the mutagenicity of photochemical products produced by exposure of the polycyclic aromatic hydrocarbons benzo(a)pyrene and 9,10-dimethylanthracene or the aromatic amines 2-aminofluorene, 2-aminoanthracene and 2-aminonaphthalene to sunlight or to ultraviolet light (UVA). 2-Aminofluorene, giving the most active products, was further investigated with respect to the mechanism of photoactivation and the chemical identity of the photochemical products. Screening of HPLC resolved photochemical products demonstrated that the majority of the mutagenicity was localized to one peak - which co-chromatographed with 2-nitrofluorene.

  11. Emission of polycyclic aromatic hydrocarbons from selected processes in steelworks.

    PubMed

    Baraniecka, Joanna; Pyrzy?ska, Krystyna; Szewczy?ska, Ma?gorzata; Po?niak, Ma?gorzata; Dobrzy?ska, Elzbieta

    2010-11-15

    The emission of polycyclic aromatic hydrocarbons from selected processes in steelworks in southern Poland was investigated. Size-segregated samples of air particulate matter (<0.25, 0.25-0.5, 0.5-1.0, 1.0-2.5 and 2.5-10 ?m) were collected at the electric arc furnace and rolling mill. The PAHs were sampled with the personal cascade impactor and identified by HPLC with fluorescence detector. The obtained results showed that collected PAH contents were significantly higher at the electric arc furnace. The highest content of total PAHs (93 ng m(-3)) was present in the smallest particles of 0.5 ?m aerodynamic diameter or less, indicating that the ultrafine particles have a high contribution in the overall PM(2.5) fine fraction. Concentrations of Py, CH, BbF, BaP and BghiP came to 76% of total PAHs content in <0.25 ?m fraction. The five- and six-ring compounds (BbF, BkF, BaP, DBA, BghiP) with 4-ring chrysene presented typical unimodal size distribution with one predominant peak for this particles' diameter. Phenanthrene and fluoranthene exhibited highest concentrations on coarse particles in the range of 10-2.5 ?m, decreasing with decrease of a particle size fraction. Using the toxic equivalent factor (TEF), the mean contributions of the carcinogenic potency of BaP to the air samples collected at the arc furnace and rolling mill (fraction below 0.25 ?m) were determined to be 66.3% and 50.3%, respectively. PMID:20675043

  12. Exposure to polycyclic aromatic hydrocarbons among Dutch children.

    PubMed Central

    van Wijnen, J H; Slob, R; Jongmans-Liedekerken, G; van de Weerdt, R H; Woudenberg, F

    1996-01-01

    We determined the urinary 1-hydroxypyrene (1-HP) concentration and the creatinine-adjusted 1-HP concentration in 644 randomly selected Dutch children, aged 1-6 years and living in five areas with roughly different levels of polycyclic aromatic hydrocarbons (PAHs) in soil and ambient air. The presence of other factors that might influence the exposure to PAHs was studied using a questionnaire. To evaluate the reliability of a single urinary 1-HP determination, measurements were repeated after 3 weeks for approximately 200 children. The mean urinary 1-HP content of the total study population was 2.06 nmol/l. This varied from 1.58 nmol/l in the reference area (Flevoland) to 2.71 nmol/l in the valley of the Geul. Only indoor sources of PAHs showed a small, positive association with urinary 1-HP. The urinary 1-HP concentrations of children from the valley of the Geul were higher (p < 0.01) and those of children from a suburb of Amsterdam were lower (p < 0.01) than those of children from the reference area. The possible ambient environment-related differences were probably too small to be detected in the variations of the intake of PAHs from the daily diet. The reliability of a single 1-HP measurement was low. Similar results were obtained with the creatinine-adjusted data. In one neighborhood built on coal-mine tailings, the urinary 1-HP content in children was weakly but positively associated with the PAH content in the upper soil layer of the garden of their homes. However, this association was not found for the children from the other neighborhood built on coal-mine tailings and with similar PAH levels in soil. PMID:8743441

  13. Polycyclic aromatic hydrocarbons in agricultural soils in Poland: preliminary proposals for criteria to evaluate the level of soil contamination

    Microsoft Academic Search

    Barbara Maliszewska-Kordybach

    1996-01-01

    The contamination of agricultural soils in the Upper Silesia region of Poland with polycyclic aromatic hydrocarbons (PAH) was evaluated on the basis of three criteria: the sum of PAH content; the number of exceeded reference values for individual PAH (according Dutch regulations); the author's preliminary proposals for agricultural lands in Poland (the sum of PAH content normalized to “average soil”

  14. Are Aromatic Hydrocarbons Generated from the Atmospheric Oxidation of Biogenic Hydrocarbons?

    NASA Astrophysics Data System (ADS)

    Gratien, A.; Johnson, S. N.; Ezell, M. J.; Wingen, L. M.; Perraud, V. M.; Dawson, M.; Bennett, R.; Finlayson-Pitts, B. J.

    2010-12-01

    Biogenic volatile organic compounds (BVOCs) are estimated to account for approximately 90% of total hydrocarbon emissions. When released into the troposphere, these BVOC undergo chemical oxidation, e.g. by hydroxyl radicals (OH) and ozone (O3) during daytime, and by nitrate radicals (NO3) and ozone at night. Anthropogenic sources release into the troposphere a wide range of volatile organic compounds (VOC), also including aromatic hydrocarbons. Their major source is believed to be the combustion and the evaporation of the fuels. One question is while there are others sources of aromatics in air. For example, an aromatic hydrocarbon, p-cymene, was recently reported in air above a forest canopy that had significant emissions of terpenes (isoprene, ?-pinene, ?-pinene, limonene…), and its concentration increased as a function of altitude, suggesting its possible formation in the atmosphere. The goal of the present study was to determine whether p-cymene can be generated from reactions of biogenic hydrocarbons in air. The oxidations of isoprene, ?-pinene, ?-pinene and limonene by O3, NO3 and OH have been studied at 1 atm air under dry conditions, at high relative humidity (70% RH), or with deliquesced sodium bisulfate (acid source) on the walls of a Teflon reaction chamber. A search for the generation of aromatic hydrocarbons products was made using GC-MS and PTR-MS. p-cymene has been observed from the reactions of ?-pinene and limonene. Possible mechanisms will be presented and the atmospheric implications discussed.

  15. Isolation and characterization of novel bacteria degrading polycyclic aromatic hydrocarbons from polluted Greek soils

    Microsoft Academic Search

    Haimou Zhang; Aristeidis Kallimanis; Anna I. Koukkou; Constantin Drainas

    2004-01-01

    Three bacterial strains, designated as Wphe1, Sphe1, and Ophe1, were isolated from Greek soils contaminated with polycyclic aromatic hydrocarbon (PAH)-containing waste from the wood processing, steel, and oil refinery industries. Wphe1, Sphe1, and Ophe1 were characterized and identified as species of Pseudomonas, Microbacterium, and Paracoccus, respectively, based on Gram staining, biochemical tests, phospholipid analysis, FAME analysis, G+C content and 16S

  16. [Distribution of various polycyclic aromatic hydrocarbons in reservoir water of Estonia].

    PubMed

    Veldre, I A; Itra, A R; Paal'me, L P; Urbas, E R

    1985-01-01

    The paper presents experimental data on different polycyclic aromatic hydrocarbons (PAH) in water, bottom sediments and algae as well as evidence available in literature on their content in exhausts of automobiles, oil shale industry and power station. Attempts are made to reveal differences in sources of the environment pollution with allowance for different PAH/benzo(a)pyrene percentage ratio, but as the PAH ratios are relatively similar in different pollution sources this attempt was a failure. PMID:4006850

  17. Polycyclic Aromatic Hydrocarbons (PAH) in Water and Sediment from Gully Pots

    Microsoft Academic Search

    Kristin Karlsson; Maria Viklander

    2008-01-01

    A gully pot is often cleaned with the help of an eductor truck, which uses hydrodynamic pressure and a vacuum to loosen and\\u000a remove the solids and standing liquid from a gully pot. This paper considers the polycyclic aromatic hydrocarbons (PAH) content\\u000a in the gully pot mixture (water and sediment) after it has been discharged from the eductor truck. The

  18. New selective solvents of aromatic hydrocarbons based on petroleum sulfides

    SciTech Connect

    Nikitin, Yu.E.; Baikova, A.Ya.; Vakhitova, N.G.; Khorosheva, S.I.; Murinov, Yu.I.

    1985-01-01

    The present work examines the extractive properties of petroleum sulfoxides (PSO) and their mixtures with other industrial extraction agents. Substitutes are tested to find inexpensive, high-boiling selective solvents and as extractive rectification agents for aromatic hydrocarbons. Effective extraction agents were proposed for the recovery of benzene and toluene from hydrocarbon mixtures during extractive rectification. Petroleum sulfoxides and their synergistic mixtures with diethylene glycol and dimethylformamide, enabled benzene and toluene to be recovered to the extent of 91-99% with a purity of 92-98%; when recovery is from a mixture enriched with benzene, purity increases to 99.5%.

  19. Phenalenyl-based open-shell polycyclic aromatic hydrocarbons.

    PubMed

    Kubo, Takashi

    2015-02-01

    The phenalenyl radical is a polycyclic aromatic hydrocarbon (PAH) radical. Owing to its widely distributed spin structure, phenalenyl is relatively stable compared to other hydrocarbon radicals and has been studied from the viewpoint of its application to electroconductive and magnetic materials. In addition, a strong intermolecular spin-spin coupling nature is another feature of phenalenyl. This account summarizes my studies so far into PAH radicals containing the phenalenyl scaffold in terms of their amphoteric redox properties and singlet biradical character, which strongly rely on the characteristic electronic structure, that is, non-bonding character and sixfold symmetry of a singly occupied molecular orbital of the phenalenyl radical. PMID:25345729

  20. Phylogenetic comparison of two polycyclic aromatic hydrocarbon-degrading mycobacteria.

    PubMed

    Govindaswami, M; Feldhake, D J; Kinkle, B K; Mindell, D P; Loper, J C

    1995-09-01

    Two mycobacterial strains previously isolated from fossil-fuel-contaminated environments and shown to degrade four- and/or five-ring polycyclic aromatic hydrocarbons were further characterized. The two strains, PYR-I and RJGII-135, had similar growth characteristics, colony morphologies, and scotochromogenic pigmentations. DNA amplification fingerprints obtained with total genomic DNA indicated some strain similarities but with several distinctly different bands. Moreover, phylogenetic analysis based upon essentially full-length 16S rRNA gene sequences separates the two strains as distinct species within the fast-growing group of mycobacteria. Although both strains are thermosensitive, strain PYR-I has the bulged U between positions 184 and 193 characteristic of thermotolerant mycobacteria. Both strains are of potential use for reintroduction into and bioremediation of polycyclic aromatic hydrocarbon-contaminated soils. PMID:7574631

  1. Emission of polycyclic aromatic hydrocarbons from gasohol and ethanol vehicles

    Microsoft Academic Search

    Rui de Abrantes; João Vicente de Assunção; Célia Regina Pesquero; Roy Edward Bruns; Raimundo Paiva Nóbrega

    2009-01-01

    The exhaust emission of the polycyclic aromatic hydrocarbons (PAHs) considered toxic to human health were investigated on two spark ignition light duty vehicles, one being gasohol (Gasohol, in Brazil, is the generic denomination for mixtures of pure gasoline plus 20–25% of anhydrous ethyl alcohol fuel (AEAF).)-fuelled and the other a flexible-fuel vehicle fuelled with hydrated ethanol. The influence of fuel

  2. Near Infrared Spectra of Large Polycyclic Aromatic Hydrocarbons

    Microsoft Academic Search

    A. L. Mattioda; D. M. Hudgins; C. W. Bauschlicher; L. J. Allamandola

    2003-01-01

    The widespread, mid-IR interstellar emission features at 3.3, 6.2, 7.7, 8.6, and 11.2 microns are generally attributed to vibrationally excited polycyclic aromatic hydrocarbons (PAHs). Since these features typcially originate from radiation-rich regions, it has been generally thought that UV photons must dominate the interstellar excitation process since PAHs have very strong UV absorption bands. However, observations have shown that lower

  3. Chromatographic methods for carcinogenic/mutagenic nitropolycyclic aromatic hydrocarbons.

    PubMed

    Hayakawa, K

    2000-10-01

    Nitropolycyclic aromatic hydrocarbons (NPAHs), which are known to be carcinogenic and/or mutagenic, are considered to be one of the air pollutants that cause lung cancer. In the last two decades, a number of sensitive and selective methods have been developed for the determination of NPAHs and related compounds in environmental and biological samples. This paper describes the state of the art of the methods and applications. PMID:11002277

  4. Polycyclic aromatic hydrocarbons in crude and deodorized vegetable oils

    Microsoft Academic Search

    B. K. Larsson; A. T. Eriksson; M. Cervenka

    1987-01-01

    The efficiency of the refining process in removing polycyclic aromatic hydrocarbons (PAH) from crude vegetable oils was studied.\\u000a Samples of the crude oils (coconut, soybean and rapeseed oils) and the corresponding refined, deodorized oil were taken on-line\\u000a in three Swedish oil refineries and margarine manufacturing plants and analyzed for 20 different PAHs. Of the crude oils,\\u000a coconut oil had by

  5. Pollution patterns of polycyclic aromatic hydrocarbons in tobacco smoke

    Microsoft Academic Search

    Hao Lu; Lizhong Zhu

    2007-01-01

    Concentrations of polycyclic aromatic hydrocarbons (PAHs) in tobacco smoke of 12 commercial brand cigarettes were determined in a simulated chamber of 20.25m3 in size. The total concentrations of 17 PAHs (?PAHs) in the chamber were 3500 and 1152ng\\/m3 in vapor phase and particulate phase, respectively. In vapor phase, the yield of naphthalene (NA) appeared to be the most abundant (2462ng\\/cig)

  6. Thermochemical Properties of Polycyclic Aromatic Hydrocarbons (PAH) from G3MP2B3 Calculations

    E-print Network

    Pitsch, Heinz

    Thermochemical Properties of Polycyclic Aromatic Hydrocarbons (PAH) from G3MP2B3 Calculations database of thermodynamic properties for polycyclic aromatic hydrocarbons (PAH). These large aromatic. PAH are commonly assumed to be the intermediates leading to soot formation. Therefore, accurate

  7. Spectroscopic properties of polycyclic aromatic hydrocarbons (PAHs) and astrophysical implications.

    PubMed

    d'Hendecourt, L; Ehrenfreund, P

    1997-01-01

    PAHs (polycyclic aromatic hydrocarbons) are probably present as a mixture of neutral and ionized species and are responsible for the set of infrared emission bands in the 2-15 microns regions, which are observed in many different objects like reflection and planetary nebulae and external galaxies. PAHs are suggested to be the most abundant free organic molecules and ubiquitous in space. PAHs might also exist in the solid phase, included in interstellar ices in dense clouds. A complex aromatic network is expected on interstellar grains in the diffuse interstellar medium. The existence of an aromatic kerogen-like structure in carbonaceous meteorites and its similarity with interstellar spectra suggests a link between interstellar matter and primitive Solar System bodies. PMID:11541329

  8. Modeling Galactic Extinction with Dust and "Real" Polycyclic Aromatic Hydrocarbons

    NASA Astrophysics Data System (ADS)

    Mulas, Giacomo; Zonca, Alberto; Casu, Silvia; Cecchi-Pestellini, Cesare

    2013-07-01

    We investigate the remarkable apparent variety of galactic extinction curves by modeling extinction profiles with core-mantle grains and a collection of single polycyclic aromatic hydrocarbons. Our aim is to translate a synthetic description of dust into physically well-grounded building blocks through the analysis of a statistically relevant sample of different extinction curves. All different flavors of observed extinction curves, ranging from the average galactic extinction curve to virtually "bumpless" profiles, can be described by the present model. We prove that a mixture of a relatively small number (54 species in 4 charge states each) of polycyclic aromatic hydrocarbons can reproduce the features of the extinction curve in the ultraviolet, dismissing an old objection to the contribution of polycyclic aromatic hydrocarbons to the interstellar extinction curve. Despite the large number of free parameters (at most the 54 × 4 column densities of each species in each ionization state included in the molecular ensemble plus the 9 parameters defining the physical properties of classical particles), we can strongly constrain some physically relevant properties such as the total number of C atoms in all species and the mean charge of the mixture. Such properties are found to be largely independent of the adopted dust model whose variation provides effects that are orthogonal to those brought about by the molecular component. Finally, the fitting procedure, together with some physical sense, suggests (but does not require) the presence of an additional component of chemically different very small carbonaceous grains.

  9. MODELING GALACTIC EXTINCTION WITH DUST AND 'REAL' POLYCYCLIC AROMATIC HYDROCARBONS

    SciTech Connect

    Mulas, Giacomo; Casu, Silvia; Cecchi-Pestellini, Cesare [INAF-Osservatorio Astronomico di Cagliari, Strada n.54, Loc. Poggio dei Pini, I-09012 Capoterra (Italy); Zonca, Alberto, E-mail: gmulas@oa-cagliari.inaf.it, E-mail: silvia@oa-cagliari.inaf.it, E-mail: ccp@oa-cagliari.inaf.it, E-mail: azonca@oa-cagliari.inaf.it [Dipartimento di Fisica, Universita di Cagliari, Strada Prov.le Monserrato-Sestu Km 0.700, I-09042 Monserrato (Italy)

    2013-07-01

    We investigate the remarkable apparent variety of galactic extinction curves by modeling extinction profiles with core-mantle grains and a collection of single polycyclic aromatic hydrocarbons. Our aim is to translate a synthetic description of dust into physically well-grounded building blocks through the analysis of a statistically relevant sample of different extinction curves. All different flavors of observed extinction curves, ranging from the average galactic extinction curve to virtually 'bumpless' profiles, can be described by the present model. We prove that a mixture of a relatively small number (54 species in 4 charge states each) of polycyclic aromatic hydrocarbons can reproduce the features of the extinction curve in the ultraviolet, dismissing an old objection to the contribution of polycyclic aromatic hydrocarbons to the interstellar extinction curve. Despite the large number of free parameters (at most the 54 Multiplication-Sign 4 column densities of each species in each ionization state included in the molecular ensemble plus the 9 parameters defining the physical properties of classical particles), we can strongly constrain some physically relevant properties such as the total number of C atoms in all species and the mean charge of the mixture. Such properties are found to be largely independent of the adopted dust model whose variation provides effects that are orthogonal to those brought about by the molecular component. Finally, the fitting procedure, together with some physical sense, suggests (but does not require) the presence of an additional component of chemically different very small carbonaceous grains.

  10. QSARs for aromatic hydrocarbons at several trophic levels.

    PubMed

    Di Marzio, Walter; Saenz, Maria Elena

    2006-04-01

    Quantitative structure-activity relationships (QSARs) with aromatic hydrocarbons were obtained. Biological response was measured by acute toxicity of several aquatic trophic levels. The chemicals assayed were benzene, toluene, ethylbenzene, o-xylene, m-xylene, p-xylene, isopropylbenzene, n-propylbenzene, and butylbenzene. Acute toxicity tests were carried out with Scenedesmus quadricauda, as representative of primary producers; Daphnia spinulata, a zooplanctonic cladoceran; Hyalella curvispina, a benthic macroinvertebrate; and Bryconamericus iheringii, an omnivorous native fish. The EC50 or LC50 was calculated from analytical determinations of aromatic hydrocarbons. Nonlinear regression analysis between the logarithm of the octanol-water partition coefficient (log Kow) of each compounds and the toxicity end points was performed. QSARs were positively related to increases in log Kow at all trophic levels. Intertaxonomic differences were found in comparisons of algae with animals and of invertebrates with vertebrates. We observed that these differences were not significant with a log Kow higher than 3 for all organisms. Aromatic hydrocarbons with log Kow values of less than 3 showed different toxicity responses, with algae more resistant than fish and invertebrates. We concluded that this was a result of the narcotic mode of action related to liposolubility and the ability of the compound to reach its target site in the cell. The bioconcentration factor (BCF) achieved to start nonpolar narcosis fell almost 1 order of magnitude below the BCF expected from the log Kow. Predicted critical body residues for nonpolar narcosis ranged between 2 and 1 mM. PMID:16528686

  11. Mutagenic and carcinogenic properties of polycyclic aromatic hydrocarbons.

    PubMed

    Pashin, Y V; Bakhitova, L M

    1979-06-01

    The rapid development of the chemical industry, combustion of fossil fuels, and smoking of tobacco have resulted in contact of the general population with benzo(a)pyrene and other carcinogenic aromatic hydrocarbons. Persons especially at risk occupationally are those engaged in thermal processing of oil shale, coal, and heavy residual petroleum. It has been shown that polycyclic aromatic hydrocarbons require metabolic activation before they can act as mutagens or carcinogens. This metabolic activation results from interaction with microsomal enzymes present in many body cells, yielding reactive epoxides which react with DNA and produce mutations in the count frame shift or participate in covalent bounding. While opinions differ regarding the relative role of these processes in mutagenesis, considerable evidence exists which links mutagenesis and carcinogenesis. Metabolites of the polycyclic aromatic hydrocarbons which are carcinogenic are usually mutagenic, which supports the hypothesis that damage to chromosomes plays an important role in carcinogenesis. These facts open the possibility to monitoring the spread of carcinogenic substances in the biosphere by relatively simple tests whose endpoint is mutagenesis. PMID:446450

  12. Polycyclic aromatic hydrocarbons and the origin of tin deposits in the Soviet Maritime Province

    SciTech Connect

    Favorskaya, M.A.; Florovskaya, V.N.; Ogloblina, A.I.; Pikovskiy, Yu.I.; Ramenskaya, M.E.

    1986-05-01

    In recent years, interest has grown in the role of carbon compounds, including polycyclic aromatic hydrocarbons (PAH), in endogenous processes. The body of data on the contents of such compounds in rocks, ores, and minerals is extensive. Evidence has been given for a plutonic or mantle origin for certain carbon compounds. Some groups of these compounds have been considered as playing a role in mineralization. Such compounds have been identified in deposits of gold, lead-zinc, fluorite, mercury, and other minerals. It has been suggested that heteroorganic compounds are involved in heavy-element transport and deposition. Tin deposits in South Primor'ye (Maritime Province) offer a good opportunity to study the role of polycyclic aromatic hydrocarbons, as these deposits reflect a complicated multiphase igneous history and repeated hydrothermal cycles. The purpose is to identify the distribution of the PAH groups and individual compounds in the various stages.

  13. Determination of polycyclic aromatic hydrocarbons in dry tea.

    PubMed

    Adisa, Afolabi; Jimenez, Angelica; Woodham, Cara; Anthony, Kevin; Nguyen, Thao; Saleh, Mahmoud A

    2015-08-01

    Twenty-eight different tea samples sold in the United States were evaluated using high-performance liquid chromatography (HPLC) with fluorescence detection (FLD) for their contamination with polycyclic aromatic hydrocarbons (PAHs). Many PAHs exhibit carcinogenic, mutagenic, and teratogenic properties and have been related to several kinds of cancer in man and experimental animals. The presence of PAHs in environmental samples such as water, sediments, and particulate air has been extensively studied, but food samples have received little attention. Eighteen PAHs congeners were analyzed, with percentage recovery higher than 85%. Contamination expressed as the sum of the 18 analyzed PAHs was between 101 and 1337 ?g/kg on dry mass and the average contents in all of the 28 examined samples was 300 ?g/kg on dry mass. Seven of the congeners were found in all samples with wide ranges of concentrations as follows: fluorene (7-48 ?g/kg), anthracene (1-31 ?g/kg), pyrene (1-970 ?g/kg), benzo(a)anthracene (1-18 ?g/kg) chrysene (17-365 ?g/kg), benzo(a)pyrene (1-29 ?g/kg), and indeno(1,2,3-cd)pyrene (4-119 ?g/kg). The two most toxic congeners benzo(a)pyrene and dibenzo(a,h)anthracene were found at high concentrations only in Earl Grey Twinnings, Earl Grey Harney& Sons Fine Teas, and Chai Ultra Spice Black Tea Twinnings. Six PAH congeners are considered as suspected carcinogens (U.S.EPA), formed the basis of the estimation of the toxic equivalent (TEQ), Chai Ultra-Spice Black Tea Twinnings had the highest TEQ (110.9) followed by two grey tea samples, Earl Grey Harney & Sons Fine Tea (57.7) and Earl Grey Twinnings (54.5). Decaffeinated grey teas had the lowest TEQs, decaffeinated Earl Grey Bigelow (9.4) and Green Tea Honey Lemon Decaffeinated Lipton (9.6). PMID:26065515

  14. The origin of the polycyclic aromatic hydrocarbons in meteorites

    NASA Astrophysics Data System (ADS)

    Wing, Michael R.; Bada, Jeffrey L.

    1991-09-01

    Polycyclic aromatic hydrocarbons (PAHs) in C1 and C2 Carbonaceous Chondrites appear to be the product of a high-temperature synthesis. This observation counters a prevailing view that PAHs in meteorites are a thermal alternation product of preexisting aliphatic compounds, which in turn required the presence of low-temperature mineral phases such as magnetite and hydrated phyllosilicates for their formation. Such a process would necessarily lead to a more low-temperature assemblage of PAHs, as many low-temperature minerals and compounds are extant in meteorites. Ivuna, a C1 carbonaceous chondrite, has been shown to contain abundant amounts of the three-ring PAHs phenanthrene/anthracene, but no detectable levels of the two- and four-ring PAHs naphthalene and pyrene/fluoranthene. Ivuna and other C1 carbonaceous chondrites are known to have been extensively altered by water. The aqueous solubities of PAHs indicate that some PAHs would have been mobilized during the aqueous alteration phase in meteorite parent bodies. Model geochromatography experiments using crushed serpentine or beach sand as the solid phase and water for elution suggest that the complete separation of two, three, and four-ring PAHs could be expected to occur in the parent body of C1 carbonaceous chondrites. It is proposed that aqueous fluids driven by heat in the parent body of Ivuna migrated from the interior to the surface, in the process transporting, separating and concentrating PAHs at various zones in the parent body. The presence of indigenous PAHs and absence of indigenous amino acids in the H4 ordinary chondrite Forest Vale provides support for the contention that different processes and environments contributed to the synthesis of the organic matter in the solar system.

  15. Enzymatic and genetic profiles in environmental strains grown on polycyclic aromatic hydrocarbons

    Microsoft Academic Search

    Lucia Cavalca; Nicoletta Guerrieri; Milena Colombo; Silvia Pagani; Vincenza Andreoni

    2007-01-01

    The possible generation of oxidative stress induced by aromatic hydrocarbon degradation suggests that ancillary enzyme activities\\u000a could facilitate the utilization of polycyclic aromatic hydrocarbons as sole carbon source. To investigate the metabolic profiles\\u000a of low molecular weight polycyclic aromatic hydrocarbon-degrading strains of Sphingobium chlorophenolicum, Rhodococcus\\u000a aetherovorans, Rhodococcus opacus and Mycobacterium smegmatis, the determination of the activity of putative detoxifying enzymes

  16. Composition, distribution, and characterization of polycyclic aromatic hydrocarbons in soil in Linfen, China

    SciTech Connect

    Fu, S.; Cheng, H.X.; Liu, Y.H.; Xia, X.J.; Xu, X.B. [Chinese Academy of Sciences, Beijing (China)

    2009-02-15

    A total of 10 surface soil samples representing the entire area of Linfen City were collected and analyzed for the presence of 16 polycyclic aromatic hydrocarbons. The total polycyclic aromatic hydrocarbon concentration ranged from 1.1 to 63.7 {mu} g g{sup -1}. Analysis of the sources of contamination revealed that polycyclic aromatic hydrocarbons in the soil were derived from combustion sources. Specifically, the primary source of polycyclic aromatic hydrocarbons was coal combustion, but the samples were also effected to varying degrees by traffic emissions. Furthermore, increased levels of contamination were observed in northeast Linfen due to the distribution of industrial plants.

  17. Atmospheric chlorinated polycyclic aromatic hydrocarbons in East Asia.

    PubMed

    Kakimoto, Kensaku; Nagayoshi, Haruna; Konishi, Yoshimasa; Kajimura, Keiji; Ohura, Takeshi; Hayakawa, Kazuichi; Toriba, Akira

    2014-09-01

    This study estimates atmospheric concentrations of chlorinated polycyclic aromatic hydrocarbons (ClPAHs) and polycyclic aromatic hydrocarbons (PAHs) in East Asia using a Gas Chromatograph with High Resolution Mass Spectrometer (GC-HRMS). ClPAHs are ubiquitously generated from PAHs through substitution, and some ClPAHs show higher aryl hydrocarbon receptor (AhR)-mediated activities than their parent PAHs. Atmospheric particles were collected using a high-volume air sampler equipped with a quartz-fiber filter. We determined the ClPAH concentrations of atmospheric particles collected in Japan (Sapporo, Sagamihara, Kanazawa, and Kitakyushu), Korea (Busan), and China (Beijing). The concentrations of ClPAHs were highest in the winter Beijing sample, where the total mean concentration was approximately 15-70 times higher than in the winter samples from Japan and Korea. The concentrations of ?19ClPAHs and ?9PAHs were significantly correlated in the Kanazawa and the Busan samples. This indicates that within those cities ClPAHs and PAHs share the same origin, implying direct chlorination of parent PAHs. Toxic equivalent concentrations (TEQs) of the total ClPAHs and PAHs were lowest in Kanazawa in the summer, reaching 1.18 and 2610fg-TEQm(-3) respectively, and highest in Beijing in the winter, reaching 627 and 4240000fg-TEQm(-3) respectively. PMID:24997898

  18. The effect of aromatization on the isotopic compositions of hydrocarbons during early diagenesis

    NASA Technical Reports Server (NTRS)

    Freeman, K. H.; Boreham, C. J.; Summons, R. E.; Hayes, J. M.

    1994-01-01

    Polycyclic aromatic hydrocarbons with varying degrees of aromatization were isolated from the Eocene Messel Shale (Rheingraben, Germany). The high abundances of these compounds and their structural resemblances to cyclic triterpenoid lipids are consistent with derivation from microbial rather than thermal processes. Compounds structurally related to oleanane contain from five to nine double bonds; those within a series of aromatized hopanoids contain from three to nine. All are products of diagenetic reactions that remove hydrogen or methyl groups, and, in several cases, break carbon-carbon bonds to open rings. Aromatized products are on average depleted in 13C relative to possible precursors by l.2% (range: l.5% enrichment to 4% depletion, n = 9). The dependence of 13C content on the number of double bonds is not, however, statistically significant and it must be concluded that there is no strong evidence for isotopic fractionation accompanying diagenetic aromatization. Isotopic differences between series (structures related to ursane, des-A-ursane, des-A-lupane, des-A-arborane, and possibly, des-A-gammacerane are present) are much greater, indicating that 13C contents are controlled primarily by source effects. Fractionations due to chromatographic isotope effects during HPLC ranged from 0.1 to 2.8%.

  19. The high-temperature oxidation of aromatic hydrocarbons

    NASA Technical Reports Server (NTRS)

    Brezinsky, K.

    1986-01-01

    Chemical mechanisms of the atmospheric pressure, high-temperature (875-1500 K) gas-phase oxidation of benzene, toluene, ethylbenzene, and propylbenzene are described and discussed. Oxidation trends evident from turbulent flow reactor experiments serve as the basis for the mechanisms of the oxidation of benzene and alkylated aromatics. The potential effects of very high temperatures and pressures on the chemistry of oxidation of aromatics are described. The oxidation of benzene and phenyl radical has been found to proceed in a stepwise C6-C5-C4 sequence. Species profiles obtained from flow-reactor experiments suggest that the oxidation of benzene and phenyl radical follows the generalized route via phenoxy, cyclopentadienyl and butadienyl radical. The oxidation of the C4 species branches into multiple pathways that yield copious amounts of ethylene and acetylene. Certain major trends are evident: the alkylated aromatics on initial attack either form styrene, benzyl radical or benzene. The styrene reacts further to produce a benzyl radical or benzene. The oxidation of an alkylated aromatic hydrocarbon appears eventually to reduce to the oxidation of either phenyl radical or benzene.

  20. Polycyclic aromatic hydrocarbons and the diffuse interstellar bands

    NASA Technical Reports Server (NTRS)

    Van Der Zwet, G. P.; Allamandola, L. J.

    1985-01-01

    This paper discusses some of the thermodynamic and spectroscopic properties of polycyclic aromatic hydrocarbons which make them attractive candidates as carriers of the Diffuse Interstellar Bands (DIBs). It is pointed out that, in the diffuse medium, many of these species will be partially hydrogenated and positively charged, and will absorb in the visible. The observed lineshapes and widths of the DIBs can be explained by rovibronic band contours and linebroadening due to internal conversion. Since little information is available concerning the spectroscopic properties of such species in the gas phase, a considerable amount of laboratory and theoretical work is needed.

  1. Polycyclic aromatic hydrocarbons residues in sandstorm depositions in Beijing, China

    SciTech Connect

    Fu, S.; Li, K.; Xia, X.J.; Xu, X.B. [Chinese Academy of Sciences, Beijing (China)

    2009-02-15

    This study was conducted to determine the concentration of 16 polycyclic aromatic hydrocarbons (PAHs) in sandstorm depositions in Beijing, China. The PAH concentrations in 13 samples collected in Beijing ranged from 0.18 to 3.52 {mu} g g{sup -1}. Analysis of the sources of contamination revealed that the PAHs were derived from a coal combustion source, although various effects of traffic emissions were also observed. Furthermore, the PAH levels in Beijing tended to be higher in the southeast. Finally, the Nemerow composite index revealed that the degree of pollution in the sandstorm depositions varied widely among sampling sites.

  2. Polycyclic Aromatic Hydrocarbons in Soils from European High Mountain Areas

    Microsoft Academic Search

    Roberto Quiroz; Joan O. Grimalt; Pilar Fernandez; Lluis Camarero; Jordi Catalan; Evzen Stuchlik; Hansjoerg Thies; Ulrike Nickus

    2011-01-01

    Polycyclic aromatic hydrocarbons (PAHs) were analyzed in 70 soils distributed in mountain areas such as Montseny (300–1,700 m),\\u000a Pyrenees (1,500–2,900 m), Alps (1,100–2,500 m), and Tatras (1,400–1,960 m). Average total PAH concentrations, excluding retene\\u000a and perylene, were about 400 ng\\/g in the Pyrenees and 1,300–1,600 ng\\/g in the other mountain ranges. No correlations between\\u000a PAH concentrations and total organic carbon were observed. Retene was the major

  3. Extraction Techniques for Polycyclic Aromatic Hydrocarbons in Soils

    PubMed Central

    Lau, E. V.; Gan, S.; Ng, H. K.

    2010-01-01

    This paper aims to provide a review of the analytical extraction techniques for polycyclic aromatic hydrocarbons (PAHs) in soils. The extraction technologies described here include Soxhlet extraction, ultrasonic and mechanical agitation, accelerated solvent extraction, supercritical and subcritical fluid extraction, microwave-assisted extraction, solid phase extraction and microextraction, thermal desorption and flash pyrolysis, as well as fluidised-bed extraction. The influencing factors in the extraction of PAHs from soil such as temperature, type of solvent, soil moisture, and other soil characteristics are also discussed. The paper concludes with a review of the models used to describe the kinetics of PAH desorption from soils during solvent extraction. PMID:20396670

  4. Polycyclic aromatic hydrocarbons - Primitive pigment systems in the prebiotic environment

    NASA Technical Reports Server (NTRS)

    Deamer, D. W.

    1992-01-01

    The chemical evolution of meteoritic organics in the primitive earth is examined experimentally with attention given to the photochemical effects of hydrocarbon/water mixtures. Also addressed are the generation of amphiphilic products by photochemical reactions and the transduction of light energy into potentially useful forms. Polycyclic aromatic hydrocarbons (PAHs) absorb light and exist in carbonaceous chondrites; PAHs are therefore examined as primitive pigments by means of salt solutions with pyrene, fluoranthene, and pyrene derivatives with hexadecane. The hexadecane undergoes photochemical oxidation and yields long-chain amphiphiles with oxygen supplied by water, and acid pH shifts also occur. PAHs are also tested in lipid bilayer membranes to examine light-energy transduction. Protons are found to accumulate within the membrane-bounded volume to form proton gradients, and this reaction is theorized to be a good model of primitive photochemical reactions that related to the transduction of light energy into useable forms.

  5. Polycyclic aromatic hydrocarbons as plausible prebiotic membrane components.

    PubMed

    Groen, Joost; Deamer, David W; Kros, Alexander; Ehrenfreund, Pascale

    2012-08-01

    Aromatic molecules delivered to the young Earth during the heavy bombardment phase in the early history of our solar system were likely to be among the most abundant and stable organic compounds available. The Aromatic World hypothesis suggests that aromatic molecules might function as container elements, energy transduction elements and templating genetic components for early life forms. To investigate the possible role of aromatic molecules as container elements, we incorporated different polycyclic aromatic hydrocarbons (PAH) in the membranes of fatty acid vesicles. The goal was to determine whether PAH could function as a stabilizing agent, similar to the role that cholesterol plays in membranes today. We studied vesicle size distribution, critical vesicle concentration and permeability of the bilayers using C(6)-C(10) fatty acids mixed with amphiphilic PAH derivatives such as 1-hydroxypyrene, 9-anthracene carboxylic acid and 1,4 chrysene quinone. Dynamic Light Scattering (DLS) spectroscopy was used to measure the size distribution of vesicles and incorporation of PAH species was established by phase-contrast and epifluorescence microscopy. We employed conductimetric titration to determine the minimal concentration at which fatty acids could form stable vesicles in the presence of PAHs. We found that oxidized PAH derivatives can be incorporated into decanoic acid (DA) vesicle bilayers in mole ratios up to 1:10 (PAH:DA). Vesicle size distribution and critical vesicle concentration were largely unaffected by PAH incorporation, but 1-hydroxypyrene and 9-anthracene carboxylic acid lowered the permeability of fatty acid bilayers to small solutes up to 4-fold. These data represent the first indication of a cholesterol-like stabilizing effect of oxidized PAH derivatives in a simulated prebiotic membrane. PMID:22798228

  6. Polycyclic Aromatic Hydrocarbons (PAHs), nitrated PAHs and oxygenated PAHs in ambient air of the

    E-print Network

    Paris-Sud XI, Université de

    1 Polycyclic Aromatic Hydrocarbons (PAHs), nitrated PAHs and oxygenated PAHs in ambient air + particle phases) of 16 polycyclic aromatic hydrocarbons (PAHs), 17 nitrated PAHs (NPAHs) and 9 oxygenated PAHs (OPAHs) were carried out during July 2004 on three different sites (urban, sub-urban and rural

  7. hal-00258891,version1-25Feb2008 Polycyclic Aromatic Hydrocarbons (PAH's) in dense cloud

    E-print Network

    Paris-Sud XI, Université de

    hal-00258891,version1-25Feb2008 Polycyclic Aromatic Hydrocarbons (PAH's) in dense cloud chemistry V aromatic hydrocarbons (PAH's). This omission is unfortunate because from the few studies that have been done on the sub- ject, it is known that the inclusion of PAH's can affect the gas-phase chemistry

  8. 1 Solvent-Extractable Polycyclic Aromatic Hydrocarbons in Biochar: 2 Influence of Pyrolysis Temperature and Feedstock

    E-print Network

    1 Solvent-Extractable Polycyclic Aromatic Hydrocarbons in Biochar: 2 Influence of Pyrolysis Supporting Information 10 ABSTRACT: Despite the increasing agricultural use of biochar as a way of combining of polycyclic aromatic hydrocarbons (PAHs) that 14 inevitably form and associate with biochar. To close

  9. Partition characteristics of polycyclic aromatic hydrocarbons on soils and sediments

    USGS Publications Warehouse

    Chiou, C.T.; Mcgroddy, S.E.; Kile, D.E.

    1998-01-01

    The partition behavior was determined for three polycyclic aromatic hydrocarbons (PAHs), i.e., naphthalene, phenanthrene, and pyrene, from water to a range of soil and sediment samples. The measured partition coefficients of the individual PAHs between soil/sediment organic matter (SOM) and water (i.e., K(oc) values) are relatively invariant either for the 'clean' (uncontaminated) soils or for the clean sediments; however, the mean K(oc) values on the sediments are about twice the values on the soils. This disparity is similar to the earlier observation for other nonpolar solutes and reflects the compositional differences between soil and sediment organic matters. No significant differences in K(oc) are observed between a clean coastal marine sediment and freshwater sediments. The coastal sediments that are significantly impacted by organic contaminants exhibit higher K(oc) values. At given K(ow) values (octanol-water), the PAHs exhibit much higher K(oc) values than other relatively nonpolar solutes (e.g., chlorinated hydrocarbons). This effect is shown to result from the enhanced partition of PAHs to SOM rather than from lower K(ow) values of PAHs at given supercooled liquid solute solubilities in water. The enhanced partition of PAHs over other nonpolar solutes in SOM provides an account of the markedly different correlations between log K(oc) and log K(ow) for PAHs and for other nonpolar solutes. The improved partition of PAHs in SOM stems apparently from the enhanced compatibility of their cohesive energy densities with those of the aromatic components in SOM. The approximate aromatic fraction in soil/sediment organic matter has been assessed by solid-state 13C-NMR spectroscopy.The partition behavior was determined for three polycyclic aromatic hydrocarbons (PAHs), i.e., naphthalene, phenanthrene, and pyrene, from water to a range of soil and sediment samples. The measured partition coefficients of the individual PAHs between soil/sediment organic matter (SOM) and water (i.e., Koc values) are relatively invariant either for the `clean' (uncontaminated) soils or for the clean sediments; however, the mean Koc values on the sediments are about twice the values on the soils. This disparity is similar to the earlier observation for other nonpolar solutes and reflects the compositional differences between soil and sediment organic matters. No significant differences in Koc are observed between a clean coastal marine sediment and freshwater sediments. The coastal sediments that are significantly impacted by organic contaminants exhibit higher Koc values. At given Kow values (octanol-water), the PAHs exhibit much higher Koc values than other relatively nonpolar solutes (e.g., chlorinated hydrocarbons). This effect is shown to result from the enhanced partition of PAHs to SOM rather than from lower Kow values of PAHs at given supercooled liquid solute solubilities in water. The enhanced partition of PAHs over other nonpolar solutes in SOM provides an account of the markedly different correlations between log Koc and log Kow for PAHs and for other nonpolar solutes. The improved partition of PAHs in SOM stems apparently from the enhanced compatibility of their cohesive energy densities with those of the aromatic components in SOM. The approximate aromatic fraction in soil/sediment organic matter has been assessed by solid-state 13C-NMR spectroscopy.

  10. Polycyclic aromatic hydrocarbons in clams Ruditapes decussatus (Linnaeus, 1758).

    PubMed

    Barreira, Luísa A; Mudge, Stephen M; Bebianno, Maria J

    2007-02-01

    The concentration of sixteen individual polycyclic aromatic hydrocarbons (PAHs) was measured in the clam Ruditapes decussatus whole soft tissues from several places of the Ria Formosa lagoon (Portugal). Total PAH (tPAH) concentrations were higher in the summer (August) and winter (January) than in the other months and the distribution pattern of the individual PAHs was generally dominated by the 4 aromatic ring PAHs, followed by the 2 + 3 aromatic rings PAHs. Benzo[a]anthracene and acenaphthene were the most representative PAHs of the two fractions. Principal components analysis (PCA) revealed that, in the Ria Formosa, seasonal variations are more important than spatial variations, due to changes in PAH source. These sources ranged from petrogenic to pyrolytic or a mixture of both. The origin of clam PAHs was also assessed by partial least squares (PLS) analysis using nineteen different PAH signatures, taken from the literature. It was possible to identify boat traffic, especially in the summer, as one of the most relevant PAH sources to the Ria Formosa. The influence of boat traffic was revealed by several signatures including diesel soot, oil and weathered oil and a mixture of different individual PAHs usually found in harbour sediments. Other relevant sources included combustion of organic matter such as forest fires and diverse domestic activities, occurring mainly in the summer. Most of the clams were considered safe for human consumption, except for some point samples, which presented unusually high PAH concentrations, suggesting the need for a regular survey of PAHs in clam tissues. PMID:17285162

  11. Secondary organic aerosol from polycyclic aromatic hydrocarbons in Southeast Texas

    NASA Astrophysics Data System (ADS)

    Zhang, Hongliang; Ying, Qi

    2012-08-01

    Recent chamber studies show that low-volatility gas phase precursors such as polycyclic aromatic hydrocarbons (PAHs) can be a significant source of secondary organic aerosol (SOA). In this work, formation of SOA from the photo-oxidation products of PAHs is added to the SOA modeling framework of the Community Multiscale Air Quality (CMAQ) model to determine the regional distribution of SOA products from PAHs (PAH-SOA) and the contributions from sources in Southeast Texas during the Texas Air Quality Study 2006 (TexAQS 2006). Results show that PAHs released from anthropogenic sources can produce SOA mass as much as 10% of that from the traditional light aromatics or approximately 4% of total anthropogenic SOA. In areas under the influence of wildfire emissions, the amount of PAH-SOA can be as much as 50% of the SOA from light aromatics. A source-oriented modeling framework is adopted to determine the major sources of PAH-SOA by tracking the emitted PAHs and their oxidation products in the gas and aerosol phases from different sources separately. Among the eight sources (vehicles, solvent utilization, residential wood, industries, natural gas combustion, coal combustion, wildfire and other sources) that are tracked in the model, wildfire, vehicles, solvent and industries are the major sources of PAH-SOA. Coal and natural gas combustion appear to be less important in terms of their contributions to PAH-SOA.

  12. Peat fires as source of polycyclic aromatic hydrocarbons in soils

    NASA Astrophysics Data System (ADS)

    Tsibart, Anna

    2013-04-01

    Polycyclic aromatic hydrocarbons (PAHs) arrive from pyrogenic sources including volcanism and the combustion of oil products and plant materials. The production of PAHs during the combustion of plant materials was considered in a number of publications, but their results were mainly obtained in laboratory experiments. Insufficient data are available on the hightemperature production of PAHs in environmental objects. For example, natural fires are frequently related to the PAH sources in landscapes, but very little factual data are available on this topic. On Polistovskii reserve (Russia, Pskov region) the soil series were separated depending on the damage to the plants; these series included soils of plots subjected to fires of different intensities, as well as soils of the background plots. The series of organic and organomineral soils significantly differed in their PAH distributions. In this series, the concentration of PAHs in the upper horizons of the peat soils little varied or slightly decreased, but their accumulation occurred at a depth of 5-10 or 10-20 cm in the soils after the fires. For example, in the series of high moor soils, the content of PAHs in the upper horizons remained almost constant; significant differences were observed in the subsurface horizons: from 2 ng/g in the background soil to 70 ng/g after the fire. In the upper horizons of the oligotrophic peat soils under pine forests, the total PAH content also varied only slightly. At the same time, the content of PAHs in the soil series increased from 15 to 90 ng/g with the increasing pyrogenic damage to the plot. No clear trends of the PAH accumulation were recorded in the organomineral soils. The content of PAHs in the soddy-podzolic soil subjected to fire slightly decreased (from 20 to 10 ng/g) compared to the less damaged soil. In peat fires, the access of oxygen to the fire zone is lower than in forest fires. The oxygen deficit acts as a factor of the organic fragments recombination and PAH production; therefore, larger amounts of PAHs are formed in peat fires. In addition, the peat fires occur directly in the soil layer; therefore, larger amounts of the resulting polyarenes remain in the soils of the fire sites. PAHs also can be formed at the heating of organic matter on the areas adjacent to the fire sites. After the combustion of peat in fires, phenanthrene, chrysene, benz[a]pyrene, and tetraphene accumulate in soils. This is mainly the group of 4-nuclear compounds with the participation of 3-nuclear phenanthrene and 5-nuclear benz[a]pyrene. The formation of high-molecular weight compounds like benz[a]pyrene and, in some places, benzo[ghi]perylene is possible during smoldering under a low oxygen supply.

  13. Assessment of polycyclic aromatic hydrocarbons (PAHs) pollution in soil of suburban areas in Tianjin, China.

    PubMed

    Lv, Jungang; Shi, Rongguang; Cai, Yanming; Liu, Yong

    2010-07-01

    Soil contamination with polycyclic aromatic hydrocarbons is an increasing problem and has aroused more and more concern in many countries, including China. In this study, representative soil samples (n = 87) of suburban areas in Tianjin (Xiqing, Dongli, Jinnan, Beichen) were evaluated for 16 polycyclic aromatic hydrocarbons. Surface soil samples were air-dried and sieved. Microwave assisted extraction was used for polycyclic aromatic hydrocarbons preparation prior to analysis with gas chromatography-mass spectrometry. The total concentrations of tested polycyclic aromatic hydrocarbons in Xiqing, Dongli, Jinnan, Beichen ranged in 58.5-2,748.3, 36.1-6,734.7, 58.5-4,502.5, 29.7-852.5 ng/g and the averages of total concentration of polycyclic aromatic hydrocarbons were 600.5, 933.6, 640.8, 257.3 ng/g, respectively. Spatial variation of polycyclic aromatic hydrocarbons in soil was illustrated; Pollution status and comparison to other cities were also investigated. Serious polycyclic aromatic hydrocarbons soil pollution was found in Dongli district, on the contrary, Bap in most sites in Beichen did not exceed relative standards and most sites in Beichen should be classified as non-contaminated soil. Principal component analysis was used to identify the possible sources of different districts. It turned out that coal combustion still was the most important sources in three districts except Beichen. Coking, traffic, cooking, biomass combustion also accounted for polycyclic aromatic hydrocarbons pollution to certain extent in different districts. These data can be further used to assess the health risk associated with soils polluted with polycyclic aromatic hydrocarbons and help local government find proper way to reduce polycyclic aromatic hydrocarbons pollution in soils. PMID:20411238

  14. Subpicogram laser-induced fluorescence detection of aromatic hydrocarbons in vapor-deposited aromatic crystals

    SciTech Connect

    Pace, C.F.; Maple, J.R.

    1985-09-01

    Aromatic hydrocarbons can be detected at subpicogram levels under conditions of high spectral resolution when the sample is placed in an aromatic crystal with molecular dimensions matched to the analyte. The advantages of using a low-temperature parent-molecule matrix have been assessed by comparing the laser-induced fluorescence and two-photon excitation of fluorescence spectra of methylnaphthalene, chloronaphthalene, and hydroxynaphthalene derivatives in durene and naphthalene crystals. It has been demonstrated that the parent-molecule matrix is well suited for use with its derivatives and that sharp spectral features result for a wide variety of substituents and substitution positions. The vapor-deposition procedure that has been developed is characterized by high spectral resolution and good quantitative precision and is often essential for detecting subpicogram levels. The potential of two-photon excitation of fluorescence for trace analysis has also been explored.

  15. Contamination of soils in the urbanized areas of Belarus with polycyclic aromatic hydrocarbons

    NASA Astrophysics Data System (ADS)

    Kukharchyk, T. I.; Khomich, V. S.; Kakareka, S. V.; Kurman, P. V.; Kozyrenko, M. I.

    2013-02-01

    The content of polycyclic aromatic hydrocarbons (PAHs) in the soils of urbanized areas, including the impact zones of Belarus, were studied. The concentrations of 16 PAHs in the soils were determined for individual and high-rise building zones, forests, and forest parks of Belarus. The levels of the PAH accumulation in the soils of different industrial enterprises and boiler stations were analyzed. Possible sources of soil contamination with PAHs were considered, and the structure of the PAHs in the soils was shown. The levels of the soil contamination were determined from the regulated parameters for individual compounds and the sum of 16 PAHs.

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

    Microsoft Academic Search

    Tripti Agarwal; Thomas D. Bucheli

    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 4.75mg\\/g (median: 1.13mg\\/g) and constituted 1–9% (median: 3%) of TOC. Indian (urban) soils had similar BC concentrations

  17. Insight into unresolved complex mixtures of aromatic hydrocarbons in heavy oil via two-dimensional gas chromatography coupled with time-of-flight mass spectrometry analysis.

    PubMed

    Weng, Na; Wan, Shan; Wang, Huitong; Zhang, Shuichang; Zhu, Guangyou; Liu, Jingfu; Cai, Di; Yang, Yunxu

    2015-06-12

    The aromatic hydrocarbon fractions of five crude oils representing a natural sequence of increasing degree of biodegradation from the Liaohe Basin, NE, China, were analyzed using conventional gas chromatography-mass spectrometry (GC-MS) and comprehensive two-dimensional gas chromatography (GC×GC). Because of the limited peak capability and low resolution, compounds in the aromatic fraction of a heavily biodegraded crude oil that were analyzed by GC-MS appeared as unresolved complex mixtures (UCMs) or GC "humps". They could be separated based on their polarity by GC×GC. UCMs are composed mainly of aromatic biomarkers and aromatic hydrocarbons with branched alkanes or cycloalkanes substituents. The quantitative results achieved by GC×GC-FID were shown that monoaromatic hydrocarbons account for the largest number and mass of UCMs in the aromatic hydrocarbon fraction of heavily biodegraded crude oil, at 45% by mass. The number and mass of diaromatic hydrocarbons ranks second at 33% by mass, followed by the aromatic biomarker compounds, triaromatic, tetraaromatic, and pentaaromatic hydrocarbons, that account for 10%, 6%, 1.5%, and 0.01% of all aromatic compounds by mass, respectively. In the heavily biodegraded oil, compounds with monocyclic cycloalkane substituents account for the largest proportion of mono- and diaromatic hydrocarbons, respectively. The C4-substituted compounds account for the largest proportion of naphthalenes and the C3-substituted compounds account for the largest proportion of phenanthrenes, which is very different from non-biodegraded, slightly biodegraded, and moderately biodegraded crude oil. It is inferred that compounds of monoaromatic, diaromatic and triaromatic hydrocarbons are affected by biodegradation, that compounds with C1-, C2-substituents are affected by the increase in degree of biodegradation, and that their relative content decreased, whereas compounds with C3-substituents or more were affected slightly or unaffected, and their relative content also increased. The varying regularity of relative content of substituted compounds may be used to reflect the degree of degradation of heavy oil. Moreover, biomarkers for the aromatic hydrocarbons of heavily biodegraded crude oil are mainly aromatic steranes, aromatic secohopanes, aromatic pentacyclotriterpanes, and benzohopanes. According to resultant data, aromatic secohopanes could be used as a specific marker because of their relatively high concentration. This aromatic compound analysis of a series of biodegraded crude oil is useful for future research on the quantitative characterization of the degree of biodegradation of heavy oil, unconventional oil maturity evaluation, oil source correlation, depositional environment, and any other geochemical problems. PMID:25939738

  18. Aging of proportional counters with gas mixtures containing impurities of aromatic hydrocarbons

    Microsoft Academic Search

    H. Andersson; T. Andersson; J. Heino; J. Huovelin; K. Kurvinern; R. Lauhakangas; S. Nenonen; A. Numminen; J. Ojala; R. Orava; J. Schultz; H. Sipila; O. Vilhu

    2004-01-01

    The aging characteristics of some aromatic hydrocarbons and some other solvents with a ring like molecule structure are systematically studied. The concentrations ranging from a few ppm to several hundred ppm were investigated. Gas mixtures with and without hydrocarbons were tested as well, to find out whether the hydrocarbons contribute to the plasma polymerisation process. An array of twelve single-wire

  19. Polycyclic Aromatic Hydrocarbons in Electrocautery Smoke during Peritonectomy Procedures

    PubMed Central

    Näslund Andréasson, Sara; Mahteme, Haile; Sahlberg, Bo; Anundi, Helena

    2012-01-01

    Objective. This study identified and quantified polycyclic aromatic hydrocarbons (PAHs) in electrocautery smoke during 40 peritonectomy procedures and investigated any correlations and/or differences between levels of PAHs and perioperative variables. Methods. PAHs were measured in personal and stationary sampling by 40?mm Millipore cassettes, for adsorption of both gaseous and particle-bound PAHs. Results. All 16 USEPA priority pollutant PAHs were detected during peritonectomy procedures, naphthalene being the most abundant. For the only two PAHs with Swedish occupational exposure limits (OELs), benzo[a]pyrene and naphthalene, limits were never exceeded. Amount of bleeding was the only perioperative variable that correlated with levels of PAHs. Conclusions. Low levels of PAHs were detected in electrocautery smoke during peritonectomy procedures, and an increased amount of bleeding correlated with higher levels of PAHs. For evaluation of long-term health effects, more studies are needed. PMID:22685482

  20. Oxygenated polycyclic aromatic hydrocarbons in urban air particulate matter

    NASA Astrophysics Data System (ADS)

    María del Rosario Sienra, M.

    Atmospheric concentrations of oxygenated polycyclic aromatic hydrocarbons (Oxy-PAHs) in Santiago de Chile city were evaluated to study particulate Oxy-PAHs profiles during cold and spring weather periods. Samples of urban particulate matter PM10 were collected during July and September-October, using a high volume air sampler provided with glass fiber filters. Samples were analyzed by gas chromatography-mass spectrometry (GC-MS). Ketones, quinones, aldehydes and carboxaldehydes were characterized and quantified. Among 12 oxy-PAHs found in the air samples, 1-pyrenecarboxaldehyde was found the greatest amount at the two sampling seasons (winter and spring) and at the two sampling sites (4.66±4.21 ng m -3 at Providencia and 2.66±2.33 ng m -3 at Las Condes, during winter). Concentration of these carcinogenic compounds is higher than other cities indicating an exposure of the inhabitants of Santiago to high amount of carcinogenic-mutagenic compounds air pollutants.

  1. Polycyclic Aromatic Hydrocarbons and Infrared Astrophysics with Spitzer

    NASA Technical Reports Server (NTRS)

    Hudgins, Douglas M.; Allamandola, L. J.

    2004-01-01

    Over the past fifteen years, thanks to significant, parallel advancements in observational, experimental, and theoretical techniques, tremendous strides have been made in our understanding of the role that carbon-rich plays in the interstellar medium (ISM). Twenty years ago, the possible existence of an abundant population of large, carbon-rich molecules in the ISM was unthinkable. Today, the unmistakable spectroscopic signatures of polycyclic aromatic hydrocarbons (PAHs) - shockingly large molecules by the standards of traditional interstellar chemistry -are recognized throughout the Universe. In this presentation, we will examine the current state of the interstellar PAH model and explore how this data, in conjunction with the unparalleled observational data provided by the Spitzer Space Telescope, can be used to draw ever-deeper insights into the physical and chemical natures of a wide range of astrophysical environments.

  2. Phototoxicity of polycyclic aromatic hydrocarbons at varying light intensities

    SciTech Connect

    Ankley, G.T.; Phipps, G.L.; Mattson, V.R.; Erickson, R.J. [Environmental Protection Agency, Duluth, MN (United States); Kosian, P.A.; Cox, J.S.; Sheedy, B.R.; Mount, D.R. [Integrated Laboratory Systems, Duluth, MN (United States)

    1994-12-31

    Conceptual models suggest that the toxicity of photoactivated polycyclic aromatic hydrocarbons (PAHs) should be a function both of chemical (PAH) dose, and intensity of the ultraviolet (UV) light to which the organism is exposed (photon dose). However, there have been no systematic studies with aquatic organisms to quantify the relationship between PAH dose and UV intensity in producing phototoxicity. In these studies, oligochaetes (Lumbriculus variegatus) were exposed, via the water, to multiple concentrations of individual PAHs known to be photoactivated (fluoranthene, pyrene, anthracene), and then placed under UV light of three different intensities. The resultant phototoxicity clearly was a function both of PAH dose and light intensity. A joint toxicity model relating toxicity to PAH concentrations and light intensity will be presented.

  3. Polycyclic Aromatic Hydrocarbons and the Diffuse Interstellar Bands: a Survey

    NASA Technical Reports Server (NTRS)

    Salama, F.; Galazutdinov, G. A.; Krelowski, J.; Allamandola, L. J.; Musaev, F. A.; DeVincenzi, Donald L. (Technical Monitor)

    1999-01-01

    We discuss the proposal relating the origin of some of the diffuse interstellar bands (DIBs) to neutral and ionized polycyclic aromatic hydrocarbons (PAHs) present in interstellar clouds. Laboratory spectra of several PAHs, isolated at low temperature in inert gas matrices, are compared with an extensive set of astronomical spectra of reddened, early type stars. From this comparison, it is concluded that PAN ions are good candidates to explain some of the DIBs. Unambiguous assignments are difficult, however, due to the shift in wavelengths and the band broadening induced in the laboratory spectra by the solid matrix. Definitive band assignments and, ultimately, the test of the of the proposal that PAH ions carry some of the DIB must await the availability of gas-phase measurements in the laboratory. The present assessment offers a guideline for future laboratory experiments by allowing the preselection of promising PAH molecules to be studied in jet expansions.

  4. Characterization of polycyclic aromatic hydrocarbons degradative soil Pseudomonas.

    PubMed

    Fuenmayor, S L; Rodriguez Lemoine, V

    1992-01-01

    Nine Pseudomonas strains, able to degrade polycycle aromatic hydrocarbons (PAHs), were isolated from enriched cultures with naphthalene, as carbon source, and soil samples from a land farming process applied on oil sludge, as inocula. Degradative tests showed that all the strains were capable to catabolize naphthalene (Nah) and phenanthrene (Phn). U2 strain transferred the selected function (Nah) to P. aeruginosa T1 (Hgr Oct+), however some of the transconjugants lost the Oct character, suggesting that it is of plasmidic nature. T1 derivatives as well the wild strains U28 and U31 transferred Nah function to P. putida AC165. All of the examined transconjugants also catabolized phenanthrene, suggesting that Nah and Phn functions in U2, U28, and U31 strains are linked and probably encoded by transferable plasmids. PMID:1343746

  5. Alkyl polycyclic aromatic hydrocarbons emissions in diesel/biodiesel exhaust

    NASA Astrophysics Data System (ADS)

    Casal, Carina S.; Arbilla, Graciela; Corrêa, Sergio M.

    2014-10-01

    Polycyclic aromatic hydrocarbons (PAHs) are widely studied in environmental matrices, such as air, water, soil and sediment, because of their toxicity, mutagenicity and carcinogenicity. Because of these properties, the environmental agencies of developed countries have listed sixteen PAHs as priority pollutants. Few countries have limits for these compounds for ambient air, but they only limit emissions from stationary and mobile sources and occupational areas. There are several studies to specifically address the 16 priority PAHs and very little for the alkyl PAHs. These compounds are more abundant, more persistent and frequently more toxic than the non-alkylated PAHs, and the toxicity increases with the number of alkyl substitutions on the aromatic ring. In this study, a method was developed for the analysis of PAHs and alkyl PAHs by using a GC-MS and large injection volume injection coupled with program temperature vaporisation, which allows for limits of detection below 1.0 ng ?L-1. Several variables were tested, such as the injection volume, injection velocity, injector initial temperature, duration of the solvent split and others. This method was evaluated in samples from particulate matter from the emissions of engines employing standard diesel, commercial diesel and biodiesel B20. Samples were collected on a dynamometer bench for a diesel engine cycle and the results ranged from 0.5 to 96.9 ng mL-1, indicating that diesel/biodiesel makes a significant contribution to the formation of PAHs and alkyl PAHs.

  6. Graphite, Polycyclic Aromatic Hydrocarbons, and the 2175 Å Extinction Feature

    NASA Astrophysics Data System (ADS)

    Duley, W. W.; Seahra, S.

    1998-11-01

    We investigate the extinction produced by small carbon particles consisting of aromatic rings in configurations similar to those of polycyclic aromatic hydrocarbon (PAH) molecules, but with varying degrees of hydrogenation, ionization, and defects. Extinction produced by candidate particles is calculated using the discrete dipole array (DDA) formalism with optical constants similar to those of graphite modified to take these changes into account. Clusters of neutral molecules as well as mixed ion-neutral clusters are also investigated. We find that certain specific carbon structures such as a dehydrogenated coronene-like molecule, C24, exhibit a plasmon-type resonance at the 2175 Å wavelength of the interstellar extinction bump. However, we find that similar fits can be obtained using a distribution of molecule shape and sizes containing up to several hundred C atoms. These results suggest that interstellar ``graphite'' may be the high-mass component of the population of PAH seen in interstellar clouds. Such particles could derive from fragments ejected from carbonaceous grains in shocks.

  7. Autothermal reforming of aliphatic and aromatic hydrocarbon liquids

    NASA Technical Reports Server (NTRS)

    Flytzani-Stephanopoulos, M.; Voecks, G. E.

    1983-01-01

    Results are presented from a study of the autothermal reforming of paraffins and aromatics over nickel catalysts. The trials were performed to examine the carbon products that appear when steam is passed over hydrocarbon liquids to form H2-rich gases, i.e., the autothermal process (ATR). Attention was given to n-hexane, n-tetradecane, benzene, and benzene solutions of naphthalene with reactant preheat to 1000-1150 F. The carbon-formation limit was sought as a function of the steam-to-carbon and oxygen to carbon molar ratios at constant pressure and the preheat temperatures. The catalyst bed was examined after each trial to identify the locations and types of carbon formed using SEM, thermal gravimetric analysis, and X ray diffraction techniques. The hydrocarbon fuels each had a separate temperature and reaction profile, as well as carbon formation characteristics. No carbon formation was observed in the upper layer of the reactor bed, while both gas phase and surface-grown deposits were present in the lower part. The results are concluded of use in the study of No. 2 fuel oil for ATR feedstock.

  8. Polycyclic aromatic hydrocarbons and cytochrome P450 in HIV pathogenesis.

    PubMed

    Rao, P S S; Kumar, Santosh

    2015-01-01

    High prevalence of cigarette smoking in HIV patients is associated with increased HIV pathogenesis and disease progression. While the effect of smoking on the occurrence of lung cancer has been studied extensively, the association between smoking and HIV pathogenesis is poorly studied. We have recently shown the possible role of cytochrome P450 (CYP) in smoking/nicotine-mediated viral replication. In this review, we focus on the potential role of CYP pathway in polycyclic aromatic hydrocarbons (PAH), important constituents of cigarette smoke, mediated HIV pathogenesis. More specifically, we will discuss the role of CYP1A1 and CYP1B1, which are the major PAH-activating CYP enzymes. Our results have shown that treatment with cigarette smoke condensate (CSC) increases viral replication in HIV-infected macrophages. CSC contains PAH, which are known to be activated by CYP1A1 and CYP1B1 into procarcinogens/toxic metabolites. The expression of these CYPs is regulated by aryl hydrocarbon receptors (AHR), the cellular target of PAH, and an important player in various diseases including cancer. We propose that PAH/AHR-mediated CYP pathway is a novel target to develop new interventions for HIV positive smokers. PMID:26082767

  9. Polycyclic aromatic hydrocarbons and cytochrome P450 in HIV pathogenesis

    PubMed Central

    Rao, P. S. S.; Kumar, Santosh

    2015-01-01

    High prevalence of cigarette smoking in HIV patients is associated with increased HIV pathogenesis and disease progression. While the effect of smoking on the occurrence of lung cancer has been studied extensively, the association between smoking and HIV pathogenesis is poorly studied. We have recently shown the possible role of cytochrome P450 (CYP) in smoking/nicotine-mediated viral replication. In this review, we focus on the potential role of CYP pathway in polycyclic aromatic hydrocarbons (PAH), important constituents of cigarette smoke, mediated HIV pathogenesis. More specifically, we will discuss the role of CYP1A1 and CYP1B1, which are the major PAH-activating CYP enzymes. Our results have shown that treatment with cigarette smoke condensate (CSC) increases viral replication in HIV-infected macrophages. CSC contains PAH, which are known to be activated by CYP1A1 and CYP1B1 into procarcinogens/toxic metabolites. The expression of these CYPs is regulated by aryl hydrocarbon receptors (AHR), the cellular target of PAH, and an important player in various diseases including cancer. We propose that PAH/AHR-mediated CYP pathway is a novel target to develop new interventions for HIV positive smokers. PMID:26082767

  10. CHEMICAL ACTIVATION OF NON-MUTAGENIC NITRATED POLYCYCLIC AROMATIC HYDROCARBONS TO MUTAGENS

    EPA Science Inventory

    Nitrated polycyclic aromatic hydrocarbons, including carcinogens, may be non-mutagenic in microorganisms because bacterial nitroreductases are unable to reduce their nitro function to proximate mutagenic hydroxylamines. The reduction of the nitro moiety can be accomplished chemic...

  11. COMPUTATIONAL METHODS FOR STUDYING THE INTERACTION BETWEEN POLYCYCLIC AROMATIC HYDROCARBONS AND BIOLOGICAL MACROMOLECULES

    EPA Science Inventory

    Computational Methods for Studying the Interaction between Polycyclic Aromatic Hydrocarbons and Biological Macromolecules . The mechanisms for the processes that result in significant biological activity of PAHs depend on the interaction of these molecules or their metabol...

  12. DIGESTIVE BIOAVAILABILITY TO A DEPOSIT FEDDER (ARENICOLA MARINA) OF POLYCYCLIC AROMATIC HYDROCARBONS ASSOCIATED WITH ANTHRPOGENIC PARTICLES

    EPA Science Inventory

    Marine sediments around urban areas serve as catch basins for anthropogenic particles containing polycyclic aromatic hydrocarbons (PAHs). Using incubations with gut fluids extracted from a deposit-feeding polychaete (Arenicola marina), we determined the digestive bioavailability ...

  13. Molecular catalytic hydrogenation of aromatic hydrocarbons and hydrotreating of coal liquids.

    SciTech Connect

    Yang, Shiyong; Stock, L.M.

    1996-05-01

    This report presents the results of research on the development of new catalytic pathways for the hydrogenation of multiring aromatic hydrocarbons and the hydrotreating of coal liquids at The University of Chicago under DOE Contract No. DE-AC22-91PC91056. The work, which is described in three parts, is primarily concerned with the research on the development of new catalytic systems for the hydrogenation of aromatic hydrocarbons and for the improvement of the quality of coal liquids by the addition of dihydrogen. Part A discusses the activation of dihydrogen by very basic molecular reagents to form adducts that can facilitate the reduction of multiring aromatic hydrocarbons. Part B examines the hydrotreating of coal liquids catalyzed by the same base-activated dihydrogen complexes. Part C concerns studies of molecular organometallic catalysts for the hydrogenation of monocyclic aromatic hydrocarbons under mild conditions.

  14. SCREENING METHODS FOR PAH (POLYNUCLEAR AROMATIC HYDROCARBON) PRIORITY POLLUTANTS IN WASTEWATER

    EPA Science Inventory

    A screening method for the determination of total polynuclear aromatic hydrocarbon (PAH) concentration in industrial effluents was developed. The method employs solvent extraction, alumina column chromatographic cleanup, and UV absorbance determination. The UV detection step util...

  15. AMENDMENT OF SEDIMENTS WITH A CARBONACEOUS RESIN REDUCES BIOAVAILABILITY OF POLYCYCLIC AROMATIC HYDROCARBONS

    EPA Science Inventory

    A series of laboratory and field test studies were conducted to evaluate the effectiveness of Ambersorb, a carbonaceous resin, in reducing bioavailability of polycyclic aromatic hydrocarbons (PAHs) in contaminated sediments collected from the field. Amending contaminated sediment...

  16. Bacterial mutagenicity of polycyclic aromatic hydrocarbons in reconstituted mixtures and crude coal tar extracts and fractions 

    E-print Network

    Onufrock, Amy Mildred

    1994-01-01

    Although polycyclic aromatic hydrocarbons (PAHS) are one of the most ubiquitous carcinogens in the environment, little is known regarding their potential mutagenic interactions. Risk assessment of complex PAH mixtures utilizes toxic equivalency...

  17. Sorption of polycyclic aromatic hydrocarbons to minerals and low-organic-carbon aquifer sediments 

    E-print Network

    Grimaldi, Gabriel Orlando

    1999-01-01

    the influence of exchangeable cations and mineral surface chemistry on the sorption of polycyclic aromatic hydrocarbons (PAH) to minerals, including kaolinite, quartz, hematite, vermiculite, and a low-organic-carbon aquifer sediment. Pyrene was selected...

  18. MULTISUBSTRATE BIODEGRADATION KINETICS FOR BINARY AND COMPLEX MIXTURES OF POLYCYCLIC AROMATIC HYDROCARBONS

    EPA Science Inventory

    Biodegradation kinetics were studied for binary and complex mixtures of nine polycyclic aromatic hydrocarbons (PAHs): naphthalene, 1-methylnaphthalene, 2-methylnaphthalene, 2-ethylnaphthalene, phenanthrene, anthracene, pyrene, fluorene and fluoranthene. Discrepancies between the ...

  19. STUDIES ON BIOREMEDIATION OF POLYCYCLIC AROMATIC HYDROCARBON-CONTAMINATED SEDIMENTS: BIOAVAILABILITY, BIODEGRADABILITY, AND TOXICITY ISSUES

    EPA Science Inventory

    The widespread contamination of aquatic sediments by polycyclic aromatic hydrocarbons (PAHs) has created a need for cost-effective bioremediation processes, on which the bioavailability and the toxicity of PAHs often have a significant impact. This research investigated the biode...

  20. METHODOLOGY FOR DETERMINATION OF POLYCYCLIC AROMATIC HYDROCARBONS AND OTHER SEMIVOLATILE ORGANIC COMPOUNDS IN HOUSE DUST

    EPA Science Inventory

    Analytical methods were validated to determine polycyclic aromatic hydrocarbons (PAH) and other semivolatile organic compounds in house dust. e also examined the storage stability of three potential markers (solanesol, nicotine, and continine) for particulate-phase environmental ...

  1. ANALYSIS OF POLYNUCLEAR AROMATIC HYDROCARBONS IN PARTICULATE MATTER BY LUMINESCENCE TECHNIQUES

    EPA Science Inventory

    Fluorescence, phosphorescence, and heavy-metal activated room temperature phosphorescence spectra were obtained for ten polycyclic aromatic hydrocarbon (PAH) reference compounds individually and in mixtures on quartz plates and particulate matter. The results indicate that multic...

  2. ASSAYING PARTICLE-BOUND POLYCYCLIC AROMATIC HYDROCARBONS (PAH) FROM ARCHIVED PM2.5 FILTERS

    EPA Science Inventory

    Airborne particulate matter contains numerous organic species, including several polycyclic aromatic hydrocarbons (PAHs) that are known or suspected carcinogens. Existing methods for measuring airborne PAHs are complex and costly, primarily because they are designed to collect...

  3. COMBINED CHEMICAL AND BIOLOGICAL OXIDATION OF SLURRY PHASE POLYCYCLIC AROMATIC HYDROCARBONS

    EPA Science Inventory

    Bioslurry treatment of polycyclic aromatic hydrocarbon (PAH)-impacted soils was demonstrated under the Superfund Innovative Technologies Evaluation (SITE)/Emerging Technologies Program (ETD) as an extension of research previously funded by IT Corporation (IT) (Brown and Sanseveri...

  4. QSARS FOR PREDICTING REDUCTIVE TRANSFORMATION RATE CONSTANTS OF HALOGENATED AROMATIC HYDROCARBONS IN ANOXIC SEDIMENT SYSTEMS

    EPA Science Inventory

    Quantitative structure-activity relationships (QSARs) are developed relating initial and final pseudo-first-order disappearance rate constants of 45 halogenated aromatic hydrocarbons in anoxic sediments to four readily available molecular descriptors: the carbon-halogen bond stre...

  5. Emission of polycyclic aromatic hydrocarbons from gasohol and ethanol vehicles

    NASA Astrophysics Data System (ADS)

    de Abrantes, Rui; Vicente de Assunção, João; Pesquero, Célia Regina; Bruns, Roy Edward; Nóbrega, Raimundo Paiva

    The exhaust emission of the polycyclic aromatic hydrocarbons (PAHs) considered toxic to human health were investigated on two spark ignition light duty vehicles, one being gasohol (Gasohol, in Brazil, is the generic denomination for mixtures of pure gasoline plus 20-25% of anhydrous ethyl alcohol fuel (AEAF).)-fuelled and the other a flexible-fuel vehicle fuelled with hydrated ethanol. The influence of fuel type and quality, aged lubricant oil type and use of fuel additives on the formation of these compounds was tested using standardized tests identical to US FTP-75 cycle. PAH sampling and chemical analysis followed the basic recommendations of method TO-13 (United States. Environmental Protection Agency, 1999. Compendium Method TO-13A - Determination of polycyclic Aromatic hydrocarbons (PAH) in Ambient Air Using Gas Chromatography/Mass Spectrometry (CG/MS). Center for environmental research information, Cincinnati, p. 78), with the necessary modification for this particular application. Results showed that the total PAH emission factor varied from 41.9 ?g km -1 to 612 ?g km -1 in the gasohol vehicle, and from 11.7 ?g km -1 to 27.4 ?g km -1 in the ethanol-fuelled vehicle, a significant difference in favor of the ethanol vehicle. Generally, emission of light molecular weight PAHs was predominant, while high molecular weights PAHs were not detected. In terms of benzo( a)pyrene toxicity equivalence, emission factors varied from 0.00984 ?g TEQ km -1 to 4.61 ?g TEQ km -1 for the gasohol vehicle and from 0.0117 ?g TEQ km -1 to 0.0218 ?g TEQ km -1 in the ethanol vehicle. For the gasohol vehicle, results showed that the use of fuel additive causes a significant increase in the emission of naphthalene and phenanthrene at a confidence level of 90% or higher; the use of rubber solvent on gasohol showed a reduction in the emission of naphthalene and phenanthrene at the same confidence level; the use of synthetic oil instead of mineral oil also contributed significantly to a decrease in the emission of naphthalene and fluorene. In relation to the ethanol vehicle, the same factors were tested and showed no statistically significant influence on PAH emission.

  6. Polycyclic Aromatic Hydrocarbons Profiles of Spent Drilling Fluids Deposited at Emu-Uno, Delta State, Nigeria

    Microsoft Academic Search

    Chukwujindu M. A. Iwegbue

    The concentrations and profiles of polycyclic aromatic hydrocarbons were determined in spent drilling fluid deposited at Emu-Uno,\\u000a Delta State of Nigeria. The total concentrations of polycyclic aromatic hydrocarbons in the spent drilling fluid deposits\\u000a ranged between 40 and 770 ?g kg?1. The PAHs profile were predominantly 2- and 3-rings with acenaphthalene, phenanthrene, fluorene being the predominant PAHs.\\u000a The prevalence of 2- and

  7. Determination of Polycyclic Aromatic Hydrocarbons in Indoor and Outdoor Air with Chromatographic Methods

    Microsoft Academic Search

    Li-Zhong Zhu; Xueyou Shen; Yong-Jian Liu

    2003-01-01

    Polycyclic aromatic hydrocarbons in indoor and outdoor air of four typical homes in Hangzhou, China were determined with a highly automated chromatographic method. The results indicated that the concentrations of the 15 polycyclic aromatic hydrocarbons in the indoor air were between 1.907 µg\\/m and 14.29 µg\\/m, which were much higher than those in the corresponding outdoor air. Because of the popular use

  8. Polycyclic aromatic hydrocarbons: from metabolism to lung cancer.

    PubMed

    Moorthy, Bhagavatula; Chu, Chun; Carlin, Danielle J

    2015-05-01

    Excessive exposure to polycyclic aromatic hydrocarbons (PAHs) often results in lung cancer, a disease with the highest cancer mortality in the United States. After entry into the lung, PAHs induce phase I metabolic enzymes such as cytochrome P450 (CYP) monooxygenases, i.e. CYP1A1/2 and 1B1, and phase II enzymes such as glutathione S-transferases, UDP glucuronyl transferases, NADPH quinone oxidoreductases (NQOs), aldo-keto reductases (AKRs), and epoxide hydrolases (EHs), via the aryl hydrocarbon receptor (AhR)-dependent and independent pathways. Humans can also be exposed to PAHs through diet, via consumption of charcoal broiled foods. Metabolism of PAHs through the CYP1A1/1B1/EH pathway, CYP peroxidase pathway, and AKR pathway leads to the formation of the active carcinogens diol-epoxides, radical cations, and o-quinones. These reactive metabolites produce DNA adducts, resulting in DNA mutations, alteration of gene expression profiles, and tumorigenesis. Mutations in xenobiotic metabolic enzymes, as well as polymorphisms of tumor suppressor genes (e.g. p53) and/or genes involved in gene expression (e.g. X-ray repair cross-complementing proteins), are associated with lung cancer susceptibility in human populations from different ethnicities, gender, and age groups. Although various metabolic activation/inactivation pathways, AhR signaling, and genetic susceptibilities contribute to lung cancer, the precise points at which PAHs induce tumor initiation remain unknown. The goal of this review is to provide a current state-of-the-science of the mechanisms of human lung carcinogenesis mediated by PAHs, the experimental approaches used to study this complex class of compounds, and future directions for research of these compounds. PMID:25911656

  9. Polycyclic aromatic hydrocarbon exhaust emissions from different reformulated diesel fuels and engine operating conditions

    NASA Astrophysics Data System (ADS)

    Borrás, Esther; Tortajada-Genaro, Luis A.; Vázquez, Monica; Zielinska, Barbara

    2009-12-01

    The study of light-duty diesel engine exhaust emissions is important due to their impact on atmospheric chemistry and air pollution. In this study, both the gas and the particulate phase of fuel exhaust were analyzed to investigate the effects of diesel reformulation and engine operating parameters. The research was focused on polycyclic aromatic hydrocarbon (PAH) compounds on particulate phase due to their high toxicity. These were analyzed using a gas chromatography-mass spectrometry (GC-MS) methodology. Although PAH profiles changed for diesel fuels with low-sulfur content and different percentages of aromatic hydrocarbons (5-25%), no significant differences for total PAH concentrations were detected. However, rape oil methyl ester biodiesel showed a greater number of PAH compounds, but in lower concentrations (close to 50%) than the reformulated diesel fuels. In addition, four engine operating conditions were evaluated, and the results showed that, during cold start, higher concentrations were observed for high molecular weight PAHs than during idling cycle and that the acceleration cycles provided higher concentrations than the steady-state conditions. Correlations between particulate PAHs and gas phase products were also observed. The emission of PAH compounds from the incomplete combustion of diesel fuel depended greatly on the source of the fuel and the driving patterns.

  10. Method of upgrading oils containing hydroxyaromatic hydrocarbon compounds to highly aromatic gasoline

    DOEpatents

    Baker, E.G.; Elliott, D.C.

    1993-01-19

    The present invention is a multi-stepped method of converting an oil which is produced by various biomass and coal conversion processes and contains primarily single and multiple ring hydroxyaromatic hydrocarbon compounds to highly aromatic gasoline. The single and multiple ring hydroxyaromatic hydrocarbon compounds in a raw oil material are first deoxygenated to produce a deoxygenated oil material containing single and multiple ring aromatic compounds. Then, water is removed from the deoxygenated oil material. The next step is distillation to remove the single ring aromatic compounds as gasoline. In the third step, the multiple ring aromatics remaining in the deoxygenated oil material are cracked in the presence of hydrogen to produce a cracked oil material containing single ring aromatic compounds. Finally, the cracked oil material is then distilled to remove the single ring aromatics as gasoline.

  11. Source identification of aromatic hydrocarbons in sediments using GC\\/MS

    Microsoft Academic Search

    S. Sporstoel; Nina Gjos; Rainer G. Lichtenthaler; Kay O. Gustavsen; Kjell Urdal; Froydis Oreld; J. Skel

    1983-01-01

    A method that may distinguish between input of polycyclic aromatic hydrocarbons (PAH) from petroleum and combustion sources is demonstrated on sediment samples. Selected series of aromatics (unsubstituted compounds and their Câ-Câ alkyl homologues) are quantified by computerized GC\\/MS. The alkyl homologue distribution (AHD) within each series and the sum of components in each series relative to the sum of all

  12. Evaluation of sediment contamination by polycyclic aromatic hydrocarbons in the Gironde estuary

    Microsoft Academic Search

    H. Budzinski; I. Jones; J. Bellocq; C. Piérard; P. Garrigues

    1997-01-01

    Surface sediments, collected in the Gironde estuary during February and October 1993, were analysed for polycyclic aromatic hydrocarbons (PAHs). The aromatic fractions were separated by liquid chromatography of the extracts and analysed by gas chromatography\\/mass spectrometry (GC\\/MS). Total PAH concentrations ranged among 1000 to 2000 ng\\/g of dry sediment. The resulting distributions and molecular ratios of specific aromatic compounds (phenanthrene,

  13. Chemical Kinetics of Polycyclic Aromatic Hydrocarbons in Protoplanetary Disks

    NASA Astrophysics Data System (ADS)

    Kress, Monika; Tran, T.; Chiar, J.; Tielens, A. G. G. M.

    2012-05-01

    Polycyclic aromatic hydrocarbons (PAHs) comprise about 10% of the carbon in the interstellar medium. There is evidence of modification of PAHs in protoplanetary disks. What happens to these molecules as they are incorporated into protoplanetary disks? We address this question by investigating the chemical kinetics of PAHs in the disk environment. Kress et al. (2010) investigated the chemical behavior of PAHs at temperatures from 1000 to 2000 K at a pressure of 1e-6 bar, and proposed the concept of the 'soot line', analogous to the 'snow line' in the solar nebula. Inside of the soot line, PAHs are irreversibly destroyed via thermally-driven reactions. We will extend this study to more realistic disk conditions and timescales. In a related project (see poster by Tran, Chiar, et al.), we are investigating the differences in the PAH physical characteristics in quiescent dense clouds versus the environment around embedded protostars. Together, these studies will help us understand (1) the fate of interstellar PAHs in planet-forming disks and (2) the relationship between interstellar and solar system PAHs. We also will investigate the soot line in disks around sub-solar mass stars (e.g. M dwarfs). This work has been supported by the NASA Astrobiology Institute's Virtual Planetary Laboratory (PI: V. Meadows) and the NASA/EPOESS program (PI: C. Phillips).

  14. Polycyclic aromatic hydrocarbon emissions from joss paper furnaces

    NASA Astrophysics Data System (ADS)

    Yang, Hsi-Hsien; Jung, Ray-Chen; Wang, Ya-Fen; Hsieh, Lien-Te

    The emissions of polycyclic aromatic hydrocarbons (PAHs) were quantified for two joss paper furnaces burning two kinds of joss papers (recycled paper made and virgin bamboo made). A cyclone and a wet scrubber were installed in series on one of the two furnaces. Particulate and gaseous PAHs were collected with a sampling system meeting the criteria of U.S. EPA Modified Method 5. Twenty-one species of PAH were analyzed by GC/MS. Individual PAH emission factors vary from less than 1 mg kg -1 fuel to several tens of mg kg -1 fuel. The total (sum of 21 compounds) and the carcinogenic PAH (benz[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, indeno[1,2,3,-cd]pyrene, dibenz[a,h]anthracene) emission factors were not statistically different for the two furnaces and averaged 71.0 and 3.2 mg kg -1, respectively. The PAH profiles showed a predominance of naphthalene (58.1%), phenanthrene (11.7%) and fluorene (7.5%). Of the two joss papers examined, bamboo-made joss paper showed less emission in both particulate and gaseous PAHs. For particulate and gaseous PAHs, the removal efficiencies of total PAHs by the air pollution control devices were 42.5% and 11.7%, respectively. PAH emission factors in high airflow conditions were generally lower than those in low airflow condition.

  15. Fullerenes, fulleranes and polycyclic aromatic hydrocarbons in the Allende meteorite

    NASA Technical Reports Server (NTRS)

    Becker, L.; Bunch, T. E.

    1997-01-01

    In this paper, we confirm our earlier observations of fullerenes (C60 and C70) in the Allende meteorite (Becker et al., 1994a, 1995). Fullerene C60 was also detected in two separate C-rich (approximately 0.5-1.0%) dark inclusions (Heymann et al., 1987) that were hand picked from the Allende sample. The amounts of C60 detected were approximately 5 and approximately 10 ppb, respectively, which is considerably less than what was detected in the Allende 15/21 sample (approximately 100 ppb; Becker et al., 1994a, 1995). This suggests that fullerenes are heterogeneously distributed in the meteorite. In addition, we present evidence for fulleranes, (C60Hx), detected in separate samples by laser desorption (reflectron) time-of-flight (TOF) mass spectrometry (LDMS). The LDMS spectra for the Allende extracts were remarkably similar to the spectra generated for the synthetic fullerane mixtures. Several fullerane products were synthesized using a Rh catalyst (Becker et al., 1993a) and separated using high-performance liquid chromatography (HPLC). Polycyclic aromatic hydrocarbons (PAHs) were also observed ppm levels) that included benzofluoranthene and corannulene, a cup-shaped molecule that has been proposed as a precursor molecule to the formation of fullerenes in the gas phase (Pope et al., 1993).

  16. Mild extractability and bioavailability of polycyclic aromatic hydrocarbons in soil

    SciTech Connect

    Tang, J.; Alexander, M.

    1999-12-01

    A study was conducted to determine the relationship between bioavailability of unaged and aged polycyclic aromatic hydrocarbons (PAHs) in soil and the amounts detected by mild solvent extraction. More aged than unaged anthracene remained in Lima loam following introduction of earthworms (Eisenia foetida), a mixed culture containing anthracene-degrading microorganisms, or earthworms or wheat after bacterial biodegradation of the compound. Aging decreased the percentage of anthracene recovered by mild extraction with n-butanol from soil following introduction of earthworms, growth of wheat, biodegradation by bacteria, or when maintained sterile. Biodegradation resulted in a marked decrease in the percentage of aged and unaged anthracene recovered from soil by mild extraction with n-butanol or ethyl acetate. Aging of fluoranthene and pyrene decreased the amount removed by mild extraction with n-butanol, ethyl acetate, and propanol. The uptake of aged and unaged anthracene, fluoranthene, and pyrene by earthworms was correlated with the amounts recovered from soil by mild extraction with n-butanol, propanol, and ethyl acetate. The retention of aged and unaged anthracene by wheat and barley was correlated with the amounts recovered from soil by the same procedure. The authors suggest that mild extraction with organic solvents can be used to predict the bioavailability of PAHs in soil.

  17. Aromatized arborane/fernane hydrocarbons as biomarkers for cordaites

    NASA Astrophysics Data System (ADS)

    Auras, Stefan; Wilde, Volker; Scheffler, Kay; Hoernes, Stephan; Kerp, Hans; Püttmann, Wilhelm

    2006-12-01

    Previous palaeobotanical and palynological studies on coals from Euramerican Pennsylvanian (? Late Carboniferous) coal basins indicate a major change in coal-swamp floras, especially at the Westphalian Stephanian (?Kasimovian Gzhelian, according to Geological Time Scale 2004) boundary. A flora dominated by arborescent lycophytes was replaced by a vegetation dominated by marattialean tree ferns in various Euramerican coal basins. Earlier combined palynological and organic geochemical studies on Westphalian/Stephanian coals and shales from the Saar-Nahe Basin (Germany) revealed that the distribution of aromatized arborane/fernane hydrocarbons in solvent extracts reflects the increasing importance of seed plants, especially cordaites (extinct group of gymnosperms), conifers and pteridosperms. However, the biological source of the precursor molecules could not be specified. To clarify if the arborane/fernane derivatives MATH, MAPH, DAPH 1, and DAPH 2 in Westphalian/Stephanian coals can be assigned to one of the three potential source plant groups, we analyzed coals, sediments and fossil plant remains from different Euramerican locations with respect to their biomarker composition and stable carbon isotopic composition. Thereby, stable carbon isotopic ratios showed only insignificant variations between Westphalian and Stephanian samples and proved to be an unsuitable tool to describe floral changes during the Westphalian/Stephanian of the Saar-Nahe Basin. In contrast, we were able to show for the first time that MATH, MAPH, DAPH 1 and DAPH 2 are prominent constituents only in extracts of cordaitean macrofossils and can therefore be regarded as biomarkers for this group of gymnosperms.

  18. Polycyclic Aromatic Hydrocarbons in drinking water of Tehran, Iran

    PubMed Central

    2013-01-01

    Distribution and seasonal variation of sixteen priority polycyclic aromatic hydrocarbons (PAHs) were investigated in the drinking water of Tehran, the capital of Iran. Detected single and total PAHs concentrations were in the range of 2.01-38.96 and 32.45-733.10 ng/L, respectively, which were quite high compared to the values recorded in other areas of the world. The average occurrence of PAHs with high molecular weights was 79.55%; for example, chrysene occurred in 60.6% of the samples, with a maximum concentration of 438.96 ng/L. In addition, mean carcinogen to non-carcinogen PAHs ratio was 63.84. Although the concentration of benzo[a]pyrene, as an indicator of water pollution to PAHs, was lower than the guideline value proposed by World Health Organization (WHO) as well as that of Iranian National Drinking Water Standards for all of the samples, the obtained results indicated that carcinogen PAHs present in the drinking water of Tehran can cause threats to human health. PMID:24499505

  19. Polycyclic Aromatic Hydrocarbon Ionization Energy Lowering in Water Ices

    NASA Technical Reports Server (NTRS)

    Gudipati, Murthy S.; Allamandola, Louis J.

    2004-01-01

    In studying various interstellar and solar system ice analogs, we have recently found that upon vacuum ultraviolet photolysis, polycyclic aromatic hydrocarbons (PAHs) frozen in water ice at low temperatures are easily ionized and indefinitely stabilized as trapped ions (Gudipati; Gudipati & Allamandola). Here we report the first experimental study that shows that PAH ionization energy is significantly lowered in PAH/H2O ices, in agreement with recent theoretical work (Woon & Park). The ionization energy (IE) of the PAH studied here, quaterrylene (C40H20, IE = 6.11 eV), is lowered by up to 2.11 eV in water ice. PAH ionization energy reduction in low-temperature water ice substantially expands the astronomical regions in which trapped ions and electrons may be important. This reduction in ionization energy should also hold for other types of trapped species in waterrich interstellar, circumstellar, and solar system ices. Subject headings: ISM: clouds - methods: laboratory - molecular processes - radiation mechanisms: nonthermal -ultraviolet: ISM - ultraviolet: solar system

  20. Laboratory Infrared Spectroscopy of Cationic Polycyclic Aromatic Hydrocarbon Molecules

    NASA Astrophysics Data System (ADS)

    Oomens, Jos; Tielens, A. G. G. M.; Sartakov, Boris G.; von Helden, Gert; Meijer, Gerard

    2003-07-01

    Infrared spectroscopy of a variety of interstellar sources shows strong mid-IR emission bands, which are generally attributed to emission from highly vibrationally excited polycyclic aromatic hydrocarbon molecules (PAHs) in the neutral and, particularly, cationic states. Over the past decade, various experimental methods have been developed to record the infrared spectra of cationic PAHs in the laboratory. In this paper, we discuss available experimental spectra obtained with matrix isolation spectroscopy (MIS), infrared multiple-photon dissociation of trapped ions (MPD), dissociation spectroscopy of ionic PAH van der Waals clusters (VDW), and infrared emission (IRE). Moreover, we compare these experimental spectra to density functional theory (DFT) calculations. The main body of experimental data relies on MIS and MPD spectra, and we present a detailed comparison of results from these methods, providing linear and multiple-photon absorption data, respectively. The effects of multiple-photon absorption, as encountered in MPD, and multiple-photon emission, occurring in interstellar spectra, are carefully assessed with the use of mathematical models, which include the effects of vibrational anharmonicity. We show that an analysis of the multiple-photon and linear data can provide important information on the anharmonicity parameters, which is otherwise difficult to attain. This is illustrated with a detailed comparison of the linear and multiple-photon absorption spectra of the naphthalene cation, yielding experimental anharmonicity parameters for the IR-active modes in the 500-1700 cm-1 range.

  1. Generation of polycyclic aromatic hydrocarbons (PAHs) during woodworking operations

    PubMed Central

    Bruschweiler, Evin D.; Danuser, Brigitta; Huynh, Cong Khanh; Wild, Pascal; Schupfer, Patrick; Vernez, David; Boiteux, Philippe; Hopf, Nancy B.

    2012-01-01

    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 wood working operations, PAH 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 three 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 personal sampler device during wood working operations. We measured 21 PAH concentrations in wood dust samples by capillary gas chromatography-ion trap mass spectrometry (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 PAH exposures were between 37.5–119.8 ng m?3 during wood working operations. Our results suggest that PAH exposures are present during woodworking operations and hence could play a role in the mechanism of cancer induction related to wood dust exposure. PMID:23087908

  2. Role of radical cations in aromatic hydrocarbon carcinogenesis.

    PubMed Central

    Cavalieri, E; Rogan, E

    1985-01-01

    Carcinogenic activation of polycyclic aromatic hydrocarbons (PAH) involves two main pathways: one-electron oxidation and monooxygenation. One-electron oxidation produces PAH radical cations, which can react with cellular nucleophiles. Results from biochemical and biological experiments indicate that only PAH with ionization potentials below ca. 7.35 eV can be metabolically activated by one-electron oxidation. In addition, the radical cations of carcinogenic PAH must have relatively high charge localization to react effectively with macromolecules in target cells. Metabolic formation of PAH quinones proceeds through radical cation intermediates. Binding of benzo[a]pyrene (BP) to mouse skin DNA occurs predominantly at C-6, the position of highest charge localization in the BP radical cation, and binding of 6-methyl BP to DNA in mouse skin yields a major adduct with the 6-methyl group bound to the 2-amino group of deoxyguanosine. Studies of carcinogenicity by direct application of PAH to rat mammary gland indicate that only PAH with ionization potentials low enough for activation by one-electron oxidation produce tumors in this target tissue. These constitute some of the results which provide evidence for the involvement of one-electron oxidation in PAH carcinogenesis. PMID:3830701

  3. Atmospheric transport and outflow of polycyclic aromatic hydrocarbons from China

    SciTech Connect

    Chang Lang; Shu Tao; Wenxin Liu; Yanxu Zhang; Staci Simonich [Peking University, Beijing (China). Laboratory for Earth Surface Processes, College of Environmental Sciences

    2008-07-15

    A potential receptor influence function (PRIF) model, based on air mass forward trajectory calculations, was applied to simulate the atmospheric transport and outflow of polycyclic aromatic hydrocarbons (PAHs) emitted from China. With a 10 day atmospheric transport time, most neighboring countries and regions, as well as remote regions, were influenced by PAH emissions from China. Of the total annual PAH emission of 114 Gg, 92.7% remained within the boundary of mainland China. The geographic distribution of PRIFs within China was similar to the geographic distribution of the source regions, with high values in the North China Plain, Sichuan Basin, Shanxi, and Guizhou province. The Tarim basin and Sichuan basin had unfavorable meteorological conditions for PAH outflow. Of the PAH outflow from China (8092 tons or 7.1% of the total annual PAH emission), approximately 69.9% (5655 tons) reached no further than the offshore environment of mainland China and the South China Sea. Approximate 227, 71, 746, and 131 tons PAHs reached North Korea, South Korea, Russia-Mongolia region, and Japan, respectively, 2-4 days after the emission. Only 1.4 tons PAHs reached North America after more than 9 days. Interannual variation in the eastward PAH outflow was positively correlated to cold episodes of El Nino/Southern Oscillation. However, trans-Pacific atmospheric transport of PAHs from China was correlated to Pacific North America index (PNA) which is associated with the strength and position of westerly winds. 38 refs., 4 figs.

  4. Polycyclic aromatic hydrocarbons in the dwarf galaxy IC 10

    E-print Network

    Wiebe, D S; Lozinskaya, T A

    2011-01-01

    Infrared observations from the Spitzer Space Telescope archive are used to study the dust component of the interstellar medium in the IC~10 irregular galaxy. Dust distribution in the galaxy is compared to the distributions of H$\\alpha$ and [SII] emission, neutral hydrogen and CO clouds, and ionizing radiation sources. The distribution of polycyclic aromatic hydrocarbons (PAH) in the galaxy is shown to be highly non-uniform with the mass fraction of these particles in the total dust mass reaching 4%. PAHs tend to avoid bright HII regions and correlate well with atomic and molecular gas. This pattern suggests that PAHs form in the dense interstellar gas. We propose that the significant decrease of the PAH abundance at low metallicity is observed not only globally (at the level of entire galaxies), but also locally (at least, at the level of individual HII regions). We compare the distribution of the PAH mass fraction to the distribution of high-velocity features, that we have detected earlier in wings of H$\\alp...

  5. Infrared Spectroscopy of Matrix-Isolated Polycyclic Aromatic Hydrocarbon Cations

    NASA Technical Reports Server (NTRS)

    Hudgins, D. M.; Allamandola, L. J.

    1995-01-01

    Gaseous, ionized polycyclic aromatic hydrocarbons (PAHs) are thought to be responsible for a very common family of interstellar infrared emission bands. Here the near- and mid-infrared spectra of the cations of the five most thermodynamically favored PAHs up to coronene: phenanthrene, pyrene, benzo(e)pyrene, benzo-(ghi)perylene, and coronene, are presented to test this hypothesis. For those molecules that have been studied previously (pyrene, pyrene-d(sub 10), and coronene), band positions and relative intensities are in agreement. In all of these cases we report additional features. Absolute integrated absorbance values are given for the phenanthrene, perdeuteriophenanthrene, pyrene, benzo(ghi]perylene, and coronene cations. With the exception of coronene, the cation bands corresponding to the CC modes are typically 2-5 times more intense than those of the CH out-of-plane bending vibrations. For the cations, the CC stretching and CH in-plane bending modes give rise to bands that are an order of magnitude stronger than those of the neutral species, and the CH out-of-plane bends produce bands that are 5-20 times weaker than those of the neutral species. This behavior is similar to that found in most other PAH cations studied to date. The astronomical implications of these PAH cation spectra are also discussed.

  6. Biodegradation of polycyclic aromatic hydrocarbons in rhizosphere soil

    SciTech Connect

    Schwab, A.P.; Banks, M.K.; Arunachalam, M. [Kansas State Univ., Manhattan, KS (United States)

    1995-12-31

    Increased contaminant biodegradation in soil in the presence of plants has been demonstrated for several classes of organic compounds. Although enhanced dissipation of polycyclic aromatic hydrocarbons (PAHs) was observed previously in the rhizosphere of several plant species, the mechanism of this effect has not been assessed. A laboratory experiment was conducted to test the importance of cometabolism and the presence of common rhizosphere organic acids on the loss of PAHs (pyrene and phenanthrene) from soil. The role of cometabolism in the mineralization of pyrene was tested by observing the impact of adding phenanthrene to soil containing {sup 14}C-pyrene and observing the effects on {sup 14}CO{sub 2} generation. Adding phenanthrene apparently induced cometabolism of pyrene, particularly in the presence of organic acids. In a subsequent experiment, mineralization of pyrene to {sup 14}CO{sub 2} was significantly greater in soil from the rhizospheres of warm-season grasses, sorghum (Sorghum bicolor L.) and bermuda grass (Cynodon dactylon L.), compared to soil from alfalfa (Medicago sativa L.), which did not differ from sterilized control soil. A highly branched, fine root system appears to be more effective in enhancing biodegradation than taproots, and the presence of organic acids increases rates of PAH mineralization.

  7. DUSTY WINDS: EXTRAPLANAR POLYCYCLIC AROMATIC HYDROCARBON FEATURES OF NEARBY GALAXIES

    SciTech Connect

    McCormick, Alexander; Veilleux, Sylvain [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Rupke, David S. N., E-mail: alexm@astro.umd.edu, E-mail: veilleux@astro.umd.edu, E-mail: rupked@rhodes.edu [Rhodes College, 2000 North Parkway, Memphis, TN 38112 (United States)

    2013-09-10

    Recent observations have shown the presence of dust and molecular material in galactic winds, but relatively little is known about the distribution of these outflow components. To shed some light on this issue, we have used IRAC images from the Spitzer Space Telescope archive to investigate polycyclic aromatic hydrocarbon (PAH) emission from a sample of 16 local galaxies with known winds. Our focus on nearby sources (median distance 8.6 Mpc) has revealed detailed PAH structure in the winds and allowed us to measure extraplanar PAH emission. We have identified extraplanar PAH features on scales of {approx}0.8-6.0 kpc. We find a nearly linear correlation between the amount of extraplanar PAH emission and the total infrared flux, a proxy for star formation activity in the disk. Our results also indicate a correlation between the height of extraplanar PAH emission and star formation rate surface density, which supports the idea of a surface density threshold on the energy or momentum injection rate for producing detectable extraplanar wind material.

  8. Multiphoton ionization mass spectrometry of nitrated polycyclic aromatic hydrocarbons.

    PubMed

    Tang, Yuanyuan; Imasaka, Tomoko; Yamamoto, Shigekazu; Imasaka, Totaro

    2015-08-01

    In order to suppress the fragmentation and improve the sensitivity for determination of nitrated polycyclic aromatic hydrocarbons (NPAHs), the mechanism of multiphoton ionization was studied for the following representative NPAHs, 9-nitroanthracene, 3-nitrofluoranthene, and 1-nitropyrene. The analytes were extracted from the PM2.5 on the sampling filter ultrasonically, and were measured using gas chromatography/multiphoton ionization/time-of-flight mass spectrometry with a femtosecond tunable laser in the range from 267 to 405nm. As a result, a molecular ion was observed as the major ion and fragmentation was suppressed at wavelengths longer than 345nm. Furthermore, the detection limit measured at 345nm was measured to be the subpicogram level. The organic compounds were extracted from a 2.19mg sample of particulate matter 2.5 (PM2.5), and the extract was subjected to multiphoton ionization mass spectrometry after gas chromatograph separation. The background signals were drastically suppressed at 345nm, and the target NPAHs, including 9-nitroanthracene and 1-nitropyrene, were detected, and their concentrations were determined to be 5 and 3pg/m(3), respectively. PMID:26048831

  9. Accumulation of mutagenic polycyclic aromatic hydrocarbons in biological sludge

    SciTech Connect

    Moretti, C.J.

    1984-01-01

    Research was conducted to study the lipophilic accumulation of mutagenic polycyclic aromatic hydrocarbons (PAH) in biological sludge produced during activated sludge treatment of fixed-bed coal-gasification wastewater. The activated sludge system was viewed as a two phase chemical system to model the PAH accumulation process, and PAH distribution in this system was quantified by an equilibrium distribution coefficient. A general equation was next developed from thermodynamic principles to predict a sludge lipid-gasifier wastewater distribution coefficient for any PAH of interest. Determination of the required parameters for this equation involved the use of a modified version of the UNIFAC method for calculating activity coefficients. PAH absorption isotherms for biological sludge in gasifier wastewater were determined by running a series of equilibrium absorption experiments. The results of these experiments indicated that the predictive equation accurately estimated distribution coefficients for most of the PAH tested. A bench scale activated sludge system treating gasifier wastewater was then operated to gather further data on PAH absorption.

  10. Polycyclic aromatic hydrocarbons in stormwater runoff from sealcoated pavements.

    PubMed

    Watts, Alison W; Ballestero, Thomas P; Roseen, Robert M; Houle, James P

    2010-12-01

    Coal-tar based sealcoat has been identified as a source of polycyclic aromatic hydrocarbons (PAHs) in the environment. This study measured the long-term release of PAHs in parking lot runoff and found that the presence of coal tar sealant increased the mass of PAHs released in runoff by over an order of magnitude. PAH concentrations in stormwater from two coal tar sealed parking lots and one unsealed parking lot (control) were monitored over a two-year period. The measured flow volume and concentrations were used to calculate a mass of 9.8-10.8 kg total ?16 PAHs per hectare exported in stormwater runoff from the two sealed parking lots and 0.34 kg total ?16 PAHs per hectare from the unsealed control. The study also measured sediment PAH concentration changes in a receiving drainage and found that even partial coverage of a drainage area by coal tar sealant resulted in measurable increases in PAH sediment concentrations; PAH concentrations in sediment in a stormwater swale receiving runoff from both sealed and unsealed lots increased near the outfall from less than 4 mg/kg prior to sealing to 95.7 mg/kg after sealing. Compound ratio plots and principal components analysis were examined and were able to clearly differentiate between pre- and postsealant samples. PMID:21047119

  11. Carbonyl atmospheric reaction products of aromatic hydrocarbons in ambient air

    NASA Astrophysics Data System (ADS)

    Obermeyer, Genevieve; Aschmann, Sara M.; Atkinson, Roger; Arey, Janet

    To convert gaseous carbonyls to oximes during sampling, an XAD-4 resin denuder system pre-coated with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine and followed by analysis with methane positive chemical ionization gas chromatography/mass spectrometry was used to measure carbonyls in ambient air samples in Riverside, CA. In conjunction with similar analyses of environmental chamber OH radical-initiated reactions of o- and p-xylene, 1,2,4-trimethylbenzene, ethylbenzene, 4-hydroxy-2-butanone and 1,4-butanediol, we identified benzaldehyde, o-, m- and p-tolualdehyde and acetophenone and the dicarbonyls glyoxal, methylglyoxal, biacetyl, ethylglyoxal, 1,4-butenedial, 3-hexene-2,5-dione, 3-oxo-butanal, 1,4-butanedial and malonaldehyde in the ambient air samples. As discussed, these carbonyls and dicarbonyls can be formed from the OH radical-initiated reactions of aromatic hydrocarbons and other volatile organic compounds emitted into the atmosphere, and we conclude that in situ atmospheric formation is a major source of these carbonyls in our Riverside, CA, ambient air samples.

  12. Separation of {sup 32}P-postlabeled DNA adducts of polycyclic aromatic hydrocarbons and nitrated polycyclic aromatic hydrocarbons by HPLC

    SciTech Connect

    King, L.C.; Gallagher, J.E.; Lewtas, J. [Environmental Protection Agency, Research Triangle Park, NC (United States); George, M. [Integrated Lab. Systems, Research Triangle Park, NC (United States)

    1994-07-01

    The {sup 32}P-postlabeling assay, thin-layer chromatography, and reverse-phase high-pressure liquid chromatography (HPLC) were used to separate DNA adducts formed from 10 polycyclic aromatic hydrocarbons (PAHs) and 6 nitrated polycyclic aromatic hydrocarbons (NO{sub 2}-PAHs). The PAHs included benzo[j]fluoranthene, benzo[k]fluoranthene, indeno[1,2,3-cd]pyrene, benzo[a]pyrene, chrysene, 6-methylchrysene, 5-methylchrysene, and benz[a]anthracene. The NO{sub 2}-PAHs included 1-nitropyrene, 2-nitrofluoranthene, 3-nitrofluoranthene, 1,6-dinitropyrene, 1,3-dinitropyrene, and 1,8-dinitropyrene. Separation of seven of the major PAH-DNA adducts was achieved by an initial PAH HPLC gradient system. The major NO{sub 2}-PAH-DNA adducts were not all separated from each other using the initial PAH HPLC gradient but were clearly separated from the PAH-DNA adducts. A second NO{sub 2}-PAH HPLC gradient system was developed to separate NO{sub 2}-PAH-DNA adducts following one-dimensional TLC and HPLC analysis. HPLC profiles of NO{sub 2}-PAH-DNA adducts were compared using both adduct enhancement versions of the {sup 32}P-postlabeling assay to evaluate the use of this technique on HPLC to screen for the presence of NO{sub 2}-PAH-DNA adducts. To demonstrate the application of these separation methods to a complex mixture of DNA adducts, the chromatographic mobilities of the {sup 32}P-postlabeled DNA adduct standards (PAHs and NO{sub 2}-PAHs) were compared with those produced by a complex mixture of polycyclic organic matter (POM) extracted from diesel emission particles. The diesel-derived adducts did not elute with the identical retention time of any of the PAH or NO{sub 2}-PAH standards used in this study. HPLC analyses of the NO{sub 2}-PAH-derived adducts (butanol extracted) revealed the presence of multiple DNA adducts.

  13. Environmental Research 105 (2007) 101118 Polycyclic aromatic hydrocarbon (PAH) contamination in

    E-print Network

    2007-01-01

    Environmental Research 105 (2007) 101­118 Polycyclic aromatic hydrocarbon (PAH) contamination hydrocarbons (PAH) are widespread contaminants in the San Francisco Bay. Several exceedances of water quality criteria raise the possibility that PAH may be impacting aquatic biota. The Regional Monitoring Program

  14. Interfacial effects in a two-phase partitioning bioreactor: degradation of polycyclic aromatic hydrocarbons (PAHs)

    E-print Network

    Daugulis, Andrew J.

    hydrocarbons (PAHs) by a hydrophobic Mycobacterium Carolan T. MacLeod, Andrew J. Daugulis* Department 18 June 2004 Abstract The growth of Mycobacterium PYR-1 on polycyclic aromatic hydrocarbons (PAHs-organic interface. Results showed that agitation rate affected cell growth and PAH degradation rates, while

  15. Sources of contamination by polycyclic aromatic hydrocarbons in Spanish virgin olive oils

    Microsoft Academic Search

    Rafael Rodríguez-Acuña; María del Carmen Pérez-Camino; Arturo Cert; Wenceslao Moreda

    2008-01-01

    The presence of polycyclic aromatic hydrocarbons (PAHs) in virgin olive oils results from contamination on olive skins and the oil itself during processing. Determination of nine PAHs was carried out by isolation of the hydrocarbon fraction and subsequent clean-up by solid phase extraction, followed by RP-HPLC analysis using a programmable fluorescence detector. Contamination of olive skins depends directly on environmental

  16. POLYHALOGENATED AROMATIC HYDROCARBONS AND METABOLITES: RELATION TO CIRCULATING THYROID HORMONE AND RETINOL IN NESTLING BALD EAGLES

    E-print Network

    with significant decreases in T4, suggesting a potential negative effect on the endocrine system of nestling bald--Polyhalogenated aromatic hydrocarbons are global contaminants that are often considered to be endocrine disruptors hydrocarbons (PHAHs), many of which are considered to be endocrine disruptors, has been well documented [1

  17. UV irradiation of polycyclic aromatic hydrocarbons in ices: production of alcohols, quinones, and ethers

    NASA Technical Reports Server (NTRS)

    Bernstein, M. P.; Sandford, S. A.; Allamandola, L. J.; Gillette, J. S.; Clemett, S. J.; Zare, R. N.

    1999-01-01

    Polycyclic aromatic hydrocarbons (PAHs) in water ice were exposed to ultraviolet (UV) radiation under astrophysical conditions, and the products were analyzed by infrared spectroscopy and mass spectrometry. Peripheral carbon atoms were oxidized, producing aromatic alcohols, ketones, and ethers, and reduced, producing partially hydrogenated aromatic hydrocarbons, molecules that account for the interstellar 3.4-micrometer emission feature. These classes of compounds are all present in carbonaceous meteorites. Hydrogen and deuterium atoms exchange readily between the PAHs and the ice, which may explain the deuterium enrichments found in certain meteoritic molecules. This work has important implications for extraterrestrial organics in biogenesis.

  18. Polycyclic aromatic hydrocarbon formation in carbon-rich stellar envelopes

    NASA Technical Reports Server (NTRS)

    Cherchneff, Isabelle; Barker, John R.; Tielens, Alexander G. G. M.

    1992-01-01

    A detailed chemical kinetic scheme is applied to stellar envelope profiles of gas density and temperature profiles in order to study the formation of PAH molecules in carbon-rich stellar outflows. Chemical concentration profiles are calculated for several envelope models by integrating the coupled continuity equations that include spherically expanding flows from an inner boundary at the shock formation radius. The influence of the 'inverse greenhouse' effect experienced by small PAHs is investigated and shown to increase the PAH yield by many orders of magnitude. It is shown that the route through propargyl radicals could be an important channel to produce benzene. PAH formation yields are found to be extremely sensitive to gas density and temperature and are much smaller than values inferred from the observed dust content of late-type carbon-rich stellar envelopes. It is therefore unlikely that aromatic molecules are generated in the stellar outflow itself.

  19. Analysis and fate of aliphatic hydrocarbons, linear alkylbenzenes, polychlorinated biphenyls and polycyclic aromatic hydrocarbons in sewage sludge-amended soils

    Microsoft Academic Search

    E. Mangas; M. T. Vaquero; L. Comellas; F. Broto-Puig

    1998-01-01

    Different extraction and clean-up methods for the multi-residue determination of aliphatic hydrocarbons (AHCs), linear alkylbenzenes (LABs), polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in sewage sludge-amended soil were investigated. Soxhlet extraction with dichloromethane and actived silica gel clean-up provided the best results. HRGC with FID detection, HRGC with ECD detection, and HPLC with a programmable fluorescence detection, performed accurate

  20. Petroleum alteration by thermochemical sulfate reduction - A comprehensive molecular study of aromatic hydrocarbons and polar compounds

    NASA Astrophysics Data System (ADS)

    Walters, Clifford C.; Wang, Frank C.; Qian, Kuangnan; Wu, Chunping; Mennito, Anthony S.; Wei, Zhibin

    2015-03-01

    Thermochemical sulfate reduction (TSR) alters petroleum composition as it proceeds towards the complete oxidation of hydrocarbons to CO2. The effects of TSR on the molecular and isotopic composition of volatile species are well known; however, the non-volatile higher molecular weight aromatic and polar species have not been well documented. To address this deficiency, a suite of onshore Gulf coast oils and condensates generated from and accumulating in Smackover carbonates was assembled to include samples that experienced varying levels of TSR alteration and in reservoir thermal cracking. The entire molecular composition of aromatic hydrocarbons and NSO species were characterized and semi-quantified using comprehensive GC × GC (FID and CSD) and APPI-FTICR-MS. The concentration of thiadiamondoids is a reliable indicator of the extent of TSR alteration. Once generated by TSR, thiadiamondoids remain thermally stable in all but the most extreme reservoir temperatures (>180 °C). Hydrocarbon concentrations and distributions are influenced by thermal cracking and TSR. With increasing TSR alteration, oils become enriched in monoaromatic hydrocarbons and the distribution of high molecular weight aromatic hydrocarbons shifts towards more condensed species with a decrease in the number of alkyl carbons. Organosulfur compounds are created by the TSR process. In addition to the increase in benzothiophenes and dibenzothiophenes noted in previous studies, TSR generates condensed species containing one or more sulfur atoms that likely are composed of a single or multiple thiophenic cores. We hypothesize that these species are generated from the partial oxidation of PAHs and dealkylation reactions, followed by sulfur incorporation and condensation reactions. The organosulfur species remaining in the TSR altered oils are "proto-solid bitumen" moieties that upon further condensation, oxidation or sulfur incorporation result in highly sulfur enriched solid bitumen, which is chemically distinct from pyrobitumen formed by thermal cracking reactions. Although TSR involves the oxidation of hydrocarbons to CO2, prior studies of TSR-altered oils have not identified intermediate products. Using NESI-FTIRC-MS, the presence and distribution of oxygenated species become evident. All oils possess minor amounts of O2 and O4 species, presumable mono- and di-naphthenic acids originating from the source. As TSR progresses, the distribution of oxygenated species shifts towards increasing species with higher oxygen content, up to O8. Similar trends are observed for the SOx species. We hypothesize that these are partially oxidized condensed hydrocarbons and that these species are likely formed by the reaction proposed by Püttmann et al. (1989) for the oxidation of PAHs associated with Kupferschiefer mineralization, whereby hydrocarbons with aryl-aryl bonds incorporate sulfur to form thiophenic species. The rate of TSR is influenced by reservoir temperature and the presence of H2S. Typically, high reservoir temperatures (>140 °C) are needed for extensive TSR alteration to occur. Oil from the Gin Creek Field appears to have received a charge of H2S, presumably from TSR alteration of a down dip reservoir, which has accelerated the TSR reaction within a relatively cold reservoir (?109 °C). This condition has allowed for the generation and preservation of abundant sulfur containing species that would be thermally cracked at higher temperatures.

  1. Formation history of polycyclic aromatic hydrocarbons in galaxies

    NASA Astrophysics Data System (ADS)

    Seok, Ji Yeon; Hirashita, Hiroyuki; Asano, Ryosuke S.

    2014-04-01

    Polycyclic aromatic hydrocarbons (PAHs) are some of the major dust components in the interstellar medium (ISM). We present our evolution models for the abundance of PAHs in the ISM on a galaxy-evolution time-scale. We consider shattering of carbonaceous dust grains in interstellar turbulence as the formation mechanism of PAHs while the PAH abundance can be reduced by coagulation on to dust grains, destruction by supernova shocks, and incorporation into stars. We implement these processes in a one-zone chemical evolution model to obtain the evolution of the PAH abundance in a galaxy. We find that PAH formation becomes accelerated above certain metallicity where shattering becomes efficient. For PAH destruction, while supernova shock is the primary mechanism in the metal-poor environment, coagulation is dominant in the metal-rich environment. We compare the evolution of the PAH abundances in our models with observed abundances in galaxies with a wide metallicity range. Our models reproduce both the paucity of PAH detection in low-metallicity galaxies and the metallicity dependence of the PAH abundance in high-metallicity galaxies. The strong metallicity dependence of PAH abundance appears as a result of the strong metallicity dependence of the dust mass increase by the accretion of metals on to dust grains, which are eventually shattered into PAHs. We conclude that the observational trend of the PAH abundance can be a natural consequence of shattering of carbonaceous grains being the source of PAHs. To establish our scenario of PAH formation, observational evidence of PAH formation by shattering would be crucial.

  2. Polycyclic aromatic hydrocarbons in surface sediments of the Jialu River.

    PubMed

    Fu, Jie; Sheng, Sheng; Wen, Teng; Zhang, Zhi-Ming; Wang, Qing; Hu, Qiu-Xiang; Li, Qing-Shan; An, Shu-Qing; Zhu, Hai-Liang

    2011-07-01

    The Jialu River, an important branch of the Huaihe River in China, was seriously polluted because of rapid economic growth and urbanization. In order to evaluate the potential for serious environmental consequences as a result of anthropogenic contamination, the distribution of polycyclic aromatic hydrocarbons (PAHs) has been investigated in surface sediment samples collected in connection with field surveys of 19 sites along the Jialu River. The total concentration of the 16 USEPA priority PAHs ranged from 466.0 to 2605.6 ng/g dry weight with a mean concentration of 1363.2 ng/g. Sediment samples with the highest PAH concentrations were from the upper reaches of the river, where Zhengzhou City is located; the PAH levels in the middle and lower reaches were relatively low. According to the observed molecular indices, PAHs originated largely from the high-temperature pyrolytic process. According to the numerical effect-based sediment quality guidelines (SQGs) of the United States, the levels of PAHs in the Jialu River should not exert adverse biological effects. The total benzo[a]pyrene toxicity equivalent (TEQ) values calculated for samples varied from 50.4 to 312.8 ng/g dry weight with an average of 167.4 ng/g. The relationships between PAHs and environmental factors, including chemical properties of sediments, water quality, aquatic organisms, hydrological conditions, and anthropogenic activities, are also discussed. PAHs exerted a potential negative impact on the benthos. Settlement percentage, population density and industrial GDP per capita had a significant influence on the distribution of PAHs. PMID:21451950

  3. Polycyclic Aromatic Hydrocarbons and digestive tract cancers - a perspective

    PubMed Central

    Diggs, Deacqunita L.; Huderson, Ashley C.; Harris, Kelly L.; Myers, Jeremy N.; Banks, Leah D.; Rekhadevi, Perumalla V.; Niaz, Mohammad S.; Ramesh, Aramandla

    2011-01-01

    Cancers of the colon are most common in the Western world. In majority of these cases, there is no familial history and sporadic gene damage seems to play an important role in the development of tumors in the colon. Studies have shown that environmental factors, especially diet, play an important role in susceptibility to GI tract cancers. Consequently, environmental chemicals that contaminate food or diet during its preparation becomes important in the development of GI cancers. Polycyclic aromatic hydrocarbons (PAHs) are one such family of ubiquitous environmental toxicants. These pollutants enter the human body through consumption of contaminated food, drinking water, inhalation of cigarette smoke, automobile exhausts, and contaminated air from occupational settings. Among these pathways, dietary intake of PAHs constitutes a major source of exposure in humans. Although many reviews and books on PAHs and their ability to cause toxicity and breast or lung cancer have been published, aspects on contribution of diet, smoking and other factors towards development of digestive tract cancers and strategies to assess risk from exposure to PAHs have received much less attention. This review, therefore, focuses on dietary intake of PAHs in humans, animal models, and cell cultures used for GI cancer studies along with epidemiological findings. Bioavailability and biotransformation processes, which influence the disposition of PAHs in body and the underlying causative mechanisms of GI cancers, are also discussed. The existing data gaps and scope for future studies is also emphasized. This information is expected to stimulate research on mechanisms of sporadic GI cancers caused by exposure to environmental carcinogens. PMID:22107166

  4. Ambient polycyclic aromatic hydrocarbons and pulmonary function in children.

    PubMed

    Padula, Amy M; Balmes, John R; Eisen, Ellen A; Mann, Jennifer; Noth, Elizabeth M; Lurmann, Frederick W; Pratt, Boriana; Tager, Ira B; Nadeau, Kari; Hammond, S Katharine

    2015-05-01

    Few studies have examined the relationship between ambient polycyclic aromatic hydrocarbons (PAHs) and pulmonary function in children. Major sources include vehicular emissions, home heating, wildland fires, agricultural burning, and power plants. PAHs are an important component of fine particulate matter that has been linked to respiratory health. This cross-sectional study examines the relationship between estimated individual exposures to the sum of PAHs with 4, 5, or 6 rings (PAH456) and pulmonary function tests (forced expiratory volume in one second (FEV1) and forced expiratory flow between 25% and 75% of vital capacity) in asthmatic and non-asthmatic children. We applied land-use regression to estimate individual exposures to ambient PAHs for averaging periods ranging from 1 week to 1 year. We used linear regression to estimate the relationship between exposure to PAH456 with pre- and postbronchodilator pulmonary function tests in children in Fresno, California (N=297). Among non-asthmatics, there was a statistically significant association between PAH456 during the previous 3 months, 6 months, and 1 year and postbronchodilator FEV1. The magnitude of the association increased with the length of the averaging period ranging from 60 to 110?ml decrease in FEV1 for each 1?ng/m(3) increase in PAH456. There were no associations with PAH456 observed among asthmatic children. We identified an association between annual PAHs and chronic pulmonary function in children without asthma. Additional studies are needed to further explore the association between exposure to PAHs and pulmonary function, especially with regard to differential effects between asthmatic and non-asthmatic children. PMID:24938508

  5. Sorption characteristics of polycyclic aromatic hydrocarbons in aluminum smelter residues

    SciTech Connect

    Gijs D. Breedveld; Emilien Pelletier; Richard St. Louis; Gerard Cornelissen [Norwegian Geotechnical Institute, Oslo (Norway)

    2007-04-01

    High temperature carbon oxidation in primary aluminum smelters results in the release of polycyclic aromatic hydrocarbons (PAH) into the environment. The main source of PAH are the anodes, which are composed of petroleum coke (black carbon, BC) and coal tar pitch. To elucidate the dominant carbonaceous phase controlling the environmental fate of PAH in aluminum smelter residues (coke BC and/or coal tar), the sorptive behavior of PAHs has been determined, using passive samplers and infinite-sink desorption methods. Samples directly from the wet scrubber were studied as well as ones from an adjacent 20-year old storage lagoon and roof dust from the smelter. Carbon-normalized distribution coefficients of native PAHs were 2 orders of magnitude higher than expected based on amorphous organic carbon (AOC)/water partitioning, which is in the same order of magnitude as reported literature values for soots and charcoals. Sorption isotherms of laboratory-spiked deuterated phenanthrene showed strong (about 100 times stronger than AOC) but nonetheless linear sorption in both fresh and aged aluminum smelter residues. The absence of nonlinear behavior typical for adsorption to BC indicates that PAH sorption in aluminum smelter residues is dominated by absorption into the semi-solid coal tar pitch matrix. Desorption experiments using Tenax showed that fresh smelter residues had a relatively large rapidly desorbing fraction of PAH (35-50%), whereas this fraction was strongly reduced (11-16%) in the lagoon and roof dust material. Weathering of the coal tar residue and/or redistribution of PAH between coal tar and BC phases could explain the reduced availability in aged samples. 38 refs., 5 figs., 1 tab.

  6. Near Infrared Spectra of Large Polycyclic Aromatic Hydrocarbons.

    NASA Astrophysics Data System (ADS)

    Mattioda, A. L.; Hudgins, D. M.; Bauschlicher, C. W.; Allamandola, L. J.

    The widespread, mid-IR interstellar emission features at 3.3, 6.2, 7.7, 8.6, and 11.2 microns are generally attributed to vibrationally excited polycyclic aromatic hydrocarbons (PAHs). Since these features typcially originate from radiation-rich regions, it has been generally thought that UV photons must dominate the interstellar excitation process since PAHs have very strong UV absorption bands. However, observations have shown that lower energy photons can also pump the emission (Aitken and Roche, Uchida and Sellgren), raising questions about the PAH model. Although it has long been known that larger PAHs should absorb at longer wavelengths (e.g. Schutte et. al., Salama et al., Li and Draine) data was not available for the isolated, neutral and ionized PAHs of sizes comparable to those thought responsible for the interstellar emission features. Here the matrix-isolated near-IR (NIR) spectra (from 0.7 to 2.5 microns) are presented for the anions and cations of PAHs ranging in size from C34H16 to C50H22. These molecules are characterized by strong absorption bands in this region, bands that can account for the emission of the interstellar features from UV poor regions. These NIR PAH transitions could also contribute to the extinction curve associated with the diffuse interstellar medium. For example, band overlap, as expected from a mixture of PAHs, can contribute to the continuum. Overlapping broad bands could lead to slight undulations in the continuum reminiscent of the Very Broad Structure (VBS, e.g. Hayes et al.). Furthermore, as previously pointed out, individual PAH bands may contribute to the diffuse interstellar band (DIB) spectrum (e.g. Romanini)

  7. Polycyclic aromatic hydrocarbon ecotoxicity data for developing soil quality criteria.

    PubMed

    Jensen, John; Sverdrup, Line E

    2003-01-01

    With the overall perspective of calculating soil quality criteria (SQC) for the group of polycyclic aromatic hydrocarbons (PAHs), the existing ecotoxicity data for the soil compartment have been reviewed. The majority of data useful in the context of deriving SQC are of recent origin. Soil quality criteria are considered valuable tools for assessing the environmental risk of contamination, as they may give guidance on concentration limits for various chemicals to protect the function and structure of ecosystems. Soil quality criteria for soil-dwelling species were calculated using various assumptions and two internationally accepted methods, i.e., application of assessment factors and species sensitivity distributions, respectively. It was suggested to derive ecotoxicological soil quality criteria, which focus on the lower molecular weight PAHs, i.e., those with log Kow values lower than 5.5 or 6; this is the log Kow range where a cutoff in toxicity for terrestrial species is expected for narcotic substances. Predicted values from the two methods were similar. Calculations showed that, for four individual PAHs of three or four rings, SQC fall in the range of 1.0 and 2.5 mg kg(-1). However, as no individual PAH is fond alone it is suggested to use a sum criterion for a group of PAHs instead. The different possibilities to calculate such a sum criterion are discussed. Based on toxicity data presented here and the average abundance of different PAHs in nearly 1000 Danish soil samples, an ecotoxicological soil quality criterion of 25 mg kg(-1) dry weight for the sum of the eight PAHs acenaphthene, fluorene, anthracene, phenanthrene, pyrene, fluoranthene, benz[a]anthracene, and chrysene is suggested. PMID:15366584

  8. Ambient polycyclic aromatic hydrocarbons and pulmonary function in children

    PubMed Central

    Padula, Amy M.; Balmes, John R.; Eisen, Ellen A.; Mann, Jennifer; Noth, Elizabeth M.; Lurmann, Frederick W.; Pratt, Boriana; Tager, Ira B.; Nadeau, Kari; Hammond, S. Katharine

    2014-01-01

    Few studies have examined the relationship between ambient polycyclic aromatic hydrocarbons (PAHs) and pulmonary function in children. Major sources include vehicular emissions, home heating, wildland fires, agricultural burning, and power plants. PAHs are an important component of fine particulate matter that has been linked to respiratory health. This cross-sectional study examines the relationship between estimated individual exposures to the sum of PAHs with 4, 5, or 6 rings (PAH456) and pulmonary function tests (forced expiratory volume in one second (FEV1) and forced expiratory flow between 25% and 75% of vital capacity) in asthmatic and non-asthmatic children. We applied land-use regression to estimate individual exposures to ambient PAHs for averaging periods ranging from 1 week to 1 year. We used linear regression to estimate the relationship between exposure to PAH456 with pre- and postbronchodilator pulmonary function tests in children in Fresno, California (N =297). Among non-asthmatics, there was a statistically significant association between PAH456 during the previous 3 months, 6 months, and 1 year and postbronchodilator FEV1. The magnitude of the association increased with the length of the averaging period ranging from 60 to 110 ml decrease in FEV1 for each 1 ng/m3 increase in PAH456. There were no associations with PAH456 observed among asthmatic children. We identified an association between annual PAHs and chronic pulmonary function in children without asthma. Additional studies are needed to further explore the association between exposure to PAHs and pulmonary function, especially with regard to differential effects between asthmatic and non-asthmatic children. PMID:24938508

  9. Sorption characteristics of polycyclic aromatic hydrocarbons in aluminum smelter residues.

    PubMed

    Breedveld, Gijs D; Pelletier, Emilien; St Louis, Richard; Cornelissen, Gerard

    2007-04-01

    High temperature carbon oxidation in primary aluminum smelters results in the release of polycyclic aromatic hydrocarbons (PAH) into the environment. The main source of PAH are the anodes, which are composed of petroleum coke (black carbon, BC) and coal tar pitch. To elucidate the dominant carbonaceous phase controlling the environmental fate of PAH in aluminum smelter residues (coke BC and/or coal tar), the sorptive behavior of PAHs has been determined, using passive samplers and infinitesink desorption methods. Samples directly from the wet scrubber were studied as well as ones from an adjacent 20-year old storage lagoon and roof dust from the smelter. Carbon-normalized distribution coefficients of native PAHs were 2 orders of magnitude higher than expected based on amorphous organic carbon (AOC)/water partitioning, which is in the same order of magnitude as reported literature values for soots and charcoals. Sorption isotherms of laboratory-spiked deuterated phenanthrene showed strong (-100 times stronger than AOC) but nonetheless linear sorption in both fresh and aged aluminum smelter residues. The absence of nonlinear behavior typical for adsorption to BC indicates that PAH sorption in aluminum smelter residues is dominated by absorption into the semi-solid coal tar pitch matrix. Desorption experiments using Tenax showed that fresh smelter residues had a relatively large rapidly desorbing fraction of PAH (35-50%), whereas this fraction was strongly reduced (11-16%) in the lagoon and roof dust material. Weathering of the coal tar residue and/or redistribution of PAH between coal tar and BC phases could explain the reduced availability in aged samples. PMID:17438813

  10. STRONG POLYCYCLIC AROMATIC HYDROCARBON EMISSION FROM z {approx} 2 ULIRGs

    SciTech Connect

    Desai, Vandana; Soifer, B. T.; Melbourne, Jason [Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Dey, Arjun; Brand, Kate; Brodwin, Mark; Jannuzi, Buell T. [National Optical Astronomy Observatory, Tucson, AZ 85726-6732 (United States); Le Floc'h, Emeric [Institute for Astronomy, University of Hawaii, Honolulu, HI 96822 (United States); Armus, Lee; Teplitz, Harry [Spitzer Science Center, California Institute of Technology, Pasadena, CA 91125 (United States); Brown, Michael J. I. [School of Physics, Monash University, Clayton, Victoria 3800 (Australia); Houck, James R.; Weedman, Daniel W. [Astronomy Department, Cornell University, Ithaca, NY 14853 (United States); Ashby, Matthew L. N.; Huang Jiasheng; Smith, Howard A.; Willner, Steve P. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Gonzalez, Anthony [Department of Astronomy, University of Florida, Gainesville, FL 32611-2055 (United States)

    2009-08-01

    Using the Infrared Spectrograph on board the Spitzer Space Telescope, we present low-resolution (64 < {lambda}/{delta}{lambda} < 124), mid-infrared (20-38 {mu}m) spectra of 23 high-redshift ULIRGs detected in the Booetes field of the NOAO Deep Wide-Field Survey. All of the sources were selected to have (1) f {sub {nu}}(24 {mu}m)>0.5 mJy; (2) R - [24]>14 Vega mag; and (3) a prominent rest frame 1.6 {mu}m stellar photospheric feature redshifted into Spitzer's 3-8 {mu}m IRAC bands. Of these, 20 show emission from polycyclic aromatic hydrocarbons (PAHs), usually interpreted as signatures of star formation. The PAH features indicate redshifts in the range 1.5 < z < 3.0, with a mean of (z) = 1.96 and a dispersion of 0.30. Based on local templates, these sources have extremely large infrared luminosities, comparable to that of submillimeter galaxies. Our results confirm previous indications that the rest-frame 1.6 {mu}m stellar bump can be efficiently used to select highly obscured star-forming galaxies at z {approx} 2, and that the fraction of starburst-dominated ULIRGs increases to faint 24 {mu}m flux densities. Using local templates, we find that the observed narrow redshift distribution is due to the fact that the 24 {mu}m detectability of PAH-rich sources peaks sharply at z = 1.9. We can analogously use observed spectral energy distributions to explain the broader redshift distribution of Spitzer-detected ULIRGs that are dominated by an active galactic nucleus (AGN). Finally, we conclude that z {approx} 2 sources with a detectable 1.6 {mu}m stellar opacity feature lack sufficient AGN emission to veil the 7.7 {mu}m PAH band.

  11. Simulation of polycyclic aromatic hydrocarbons transport in multimedia

    SciTech Connect

    Chen, L.; Chu, C.J.

    1999-07-01

    Many studies have indicated that the threat from toxic air pollutants such as VOCs comes not through inhalation by humans while the pollutants are in a gaseous state but through absorption when the pollutants are in a solid state such as in an aerosol or particulate form. Pollutants such as Polycyclic Aromatic Hydrocarbons (PAHs) usually exist in a semi-volatile state. To assess the risk of the PAHs, one needs to estimate the dose of the pollutants to which a human would be exposed through various pathways. In this study, the authors modified a Spatial Multimedia Compartmental Model (SMCM) originally developed by UCLA Professor Cohen to predict the PAHs distribution among multimedia such as air, water, soil and sediment in the Taipei metropolitan area. Three PAHs were considered in this study. They are Benzo(a)pyrene, Pyrene and Chrysene. When PAHs are emitted into atmosphere, physical and chemical mechanisms may redistribute the PAHs among multimedia. Five cases of PAHs distribution in multimedia were simulated: (1) PAHs distribution in a dry condition, (2) PAHs distribution when there are different dry deposition velocities, (3) PAHs distribution under a single rainfall event, (4) PAHs distribution when there are different soil properties, (5) PAHs distribution under a random rainfall case. The simulation results are concluded: (1) In the dry case, the PAHs accumulate mostly in soil and air compartments, (2) Different dry depositing velocities will affect the PAHs distribution among compartments. (3) Different soil properties affect the PAHs concentration in the soil and sediment compartments, (4) The soil PAHs concentrations usually increase for those PAHs with a high solid/gas ratio. (5) The random rainfall only affects the PAHs concentration in the soil.

  12. Degradation of Polycyclic Aromatic Hydrocarbons (PAHs) by Laccase in Rhamnolipid Reversed Micellar System.

    PubMed

    Peng, Xin; Yuan, Xing-Zhong; Liu, Huan; Zeng, Guang-Ming; Chen, Xiao-Hong

    2015-05-01

    Rhamnolipid was applied to degrade anthracene and pyrene in reversed micelles. The parameters in degradation were optimized for the purpose of improving degradation rates. The proper amount of rhamnolipid (RL) used for degrading anthracene was 0.065 mM, while 0.075 mM for pyrene. However, reaction time for degrading both anthracene and pyrene was 48 h. The optimum water content, pH, laccase concentration, polycyclic aromatic hydrocarbon (PAH) initial concentration, and volume ratio of n-hexanol to isooctane for both were found out. The highest degradation rates of anthracene and pyrene were 37.52 and 25.58 %, respectively. Although the degradation rates were not higher than the results previous literatures reported, this method was of novelty and provided guidance in application in degrading PAHs by reversed micellar system, especially for biosurfactant-based reversed micelles. PMID:25637508

  13. Polycyclic aromatic hydrocarbon (PAH) in four fish species from different trophic levels in the Persian Gulf.

    PubMed

    Rahmanpour, Shirin; Farzaneh Ghorghani, Nasrin; Lotfi Ashtiyani, Seyede Masoumeh

    2014-11-01

    Concentration of ten polycyclic aromatic hydrocarbon (PAH) compounds were determined in liver of four fish species from different trophic levels (Aurigequula fasciata, omnivore; Alepes djedaba, carnivore; Liza abu and Sardinella albella, phytoplanktivores). In all the species, similar distributions were observed in which pyrene predominated and followed by naphthalene and acenaphthylene. L. abu accumulated the highest concentration of ?PAH, followed by S. albella, A. fasciata, and A. djedaba. No correlation between PAH content in fish liver and fish size has been found at the level of individual compounds, except for benzo[a]pyrene (p?

  14. Polycyclic Aromatic Hydrocarbons in the Martian (SNC) Meteorite ALH 84001: Hydrocarbons from Mars, Terrestrial Contaminants, or Both?

    Microsoft Academic Search

    K. L. Thomas; S. J. Clemett; C. S. Romanek; C. R. Macheling; E. K. Gibson; D. S. McKay; R. Score; R. N. Zare

    1995-01-01

    Previous work has shown that pre-terrestrial polycyclic aromatic hydrocarbons (PAHs) exist in interplanetary dust particles (IDPs) and certain meteorites [1-3]. We previously reported the first observation of PAHs in the newest member of the SNC group, Allan Hills 84001 [4] and determined that particular types of organic compounds are indigenous to ALH 84001 because they are associated with certain mineralogical

  15. Polycyclic aromatic hydrocarbon (PAH) burden of mussels ( Mytilus sp.) in different marine environments in relation with sediment PAH contamination, and bioavailability

    Microsoft Academic Search

    P Baumard; H Budzinski; P Garrigues; J. F Narbonne; T Burgeot; X Michel; J Bellocq

    1999-01-01

    Sediments and mussels (Mytilus edulis, Mytilus galloprovincialis) were sampled in different European coastal environments (Germany, France, Spain) and analysed for their polycyclic aromatic hydrocarbon (PAH) content by Gas Chromatography\\/Mass Spectrometry (GC-MS). Bioaccumulation factors of individual compounds from the sediment were calculated and discussed according to the compound solubility. The mussels showed different accumulation patterns according to the pollution source they

  16. Genome Sequence of Rhodococcus sp. 4J2A2, a Desiccation-Tolerant Bacterium Involved in Biodegradation of Aromatic Hydrocarbons.

    PubMed

    Manzanera, Maximino; García-Fontana, Cristina; Vílchez, Juan Ignacio; González-López, Jesús

    2015-01-01

    The genome sequence for Rhodococcus sp. 4J2A2, a newly described desiccation-tolerant strain that removes aromatic hydrocarbons, is reported here. The genome is estimated to be around 7.5 Mb in size, with an average G+C content of 60.77% and a predicted number of protein-coding sequences of 6,354. PMID:26044434

  17. Genome Sequence of Rhodococcus sp. 4J2A2, a Desiccation-Tolerant Bacterium Involved in Biodegradation of Aromatic Hydrocarbons

    PubMed Central

    García-Fontana, Cristina; Vílchez, Juan Ignacio; González-López, Jesús

    2015-01-01

    The genome sequence for Rhodococcus sp. 4J2A2, a newly described desiccation-tolerant strain that removes aromatic hydrocarbons, is reported here. The genome is estimated to be around 7.5 Mb in size, with an average G+C content of 60.77% and a predicted number of protein-coding sequences of 6,354. PMID:26044434

  18. Determination of aromatic hydrocarbons in bituminous emulsion sealants using headspace solid-phase microextraction and gas chromatography-mass spectrometry.

    PubMed

    Tang, Bing; Isacsson, Ulf

    2006-12-22

    The possibility of quantitative determination of aromatic hydrocarbons in bituminous emulsion sealants was investigated using headspace solid-phase microextraction (HS-SPME) followed by gas chromatography-mass spectrometry (GC-MS). The target analytes studied were benzene, toluene, ethylbenzene, p-, m-, and o-xylene (BTEX) as well as 1,3,5- and 1,2,4-trimethylbenzene. Experimental factors influencing HS-SPME efficiency were studied (sample-headspace equilibration time, extraction time and sample matrix effects). A HS-SPME method using surrogate matrix was developed. The detection limit was estimated as approximately 0.1 ppmw for the target analytes investigated. Good linearity was observed (R(2)>0.997) for all calibration curves obtained. The repeatability of the method (RSD, relative standard deviation) was found less than 10%. The accuracy of the method given by recovery of spiked samples was between 99 and 116%. The HS-SPME method developed was applied to two commercially available bituminous emulsion sealants. External calibration and standard addition approaches were investigated, and statistical paired t-test was performed. The contents of target aromatic hydrocarbons in the sealants studied varied from approximately 0.4 to 150 ppmw. The method developed shows potential as a tool for the determination of aromatic hydrocarbons in emulsified bituminous materials. PMID:17069821

  19. Applications of electrochemically-modulated liquid chromatography (EMLC): Separations of aromatic amino acids and polycyclic aromatic hydrocarbons

    SciTech Connect

    Deng, L.

    1998-03-27

    The research in this thesis explores the separation capabilities of a new technique termed electrochemically-modulated liquid chromatography (EMLC). The thesis begins with a general introduction section which provides a literature review of this technique as well as a brief background discussion of the two research projects in each of the next two chapters. The two papers which follow investigate the application of EMLC to the separation of a mixture of aromatic amino acids and of a mixture of polycyclic aromatic hydrocarbons (PAHs). The last section presents general conclusions and summarizes the thesis. References are compiled in the reference section of each chapter. The two papers have been removed for separate processing.

  20. Polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and chlorinated pesticides in background air in central Europe - investigating parameters affecting wet scavenging of polycyclic aromatic hydrocarbons

    NASA Astrophysics Data System (ADS)

    Shahpoury, P.; Lammel, G.; Holubová Šmejkalová, A.; Klánová, J.; P?ibylová, P.; Vá?a, M.

    2015-02-01

    Concentrations of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and chlorinated pesticides (CPs) were measured in air and precipitation at a background site in central Europe. ∑ PAH concentrations in air and rainwater ranged from 0.7 to 327.9 ng m-3 and below limit of quantification (< LOQ) to 2.1 × 103 ng L-1. The concentrations of PCBs and CPs in rainwater were < LOQ. ∑ PCB and ∑ CP concentrations in air ranged from < LOQ to 44.6 and < LOQ to 351.7 pg m-3, respectively. The potential relationships between PAH wet scavenging and particulate matter and rainwater properties were investigated. The concentrations of ionic species in particulate matter and rainwater were significantly correlated, highlighting the importance of particle scavenging process. Overall, higher scavenging efficiencies were found for relatively less volatile PAHs, underlining the effect of analyte gas-particle partitioning on scavenging process. The particulate matter removal by rain, and consequently PAH wet scavenging, was more effective when the concentrations of ionic species were high. In addition, the elemental and organic carbon contents of the particulate matter were found to influence the PAH scavenging.

  1. Emission of polycyclic aromatic hydrocarbons from medical waste incinerators

    NASA Astrophysics Data System (ADS)

    Lee, Wen-Jhy; Liow, Ming-Chu; Tsai, Perng-Jy; Hsieh, Lien-Te

    This study was conducted on two batch-type medical waste incinerators (MWIs), including the one with a mechanical grate (MG-MWI) and the other with a fixed grate (FG-MWI) for the disposal of general medical waste and special medical waste, respectively. Both incinerators shared the same air-pollution control devices which were installed in series, including one electrostatic precipitator (ESP) and one wet scrubber (WSB). In addition to the investigated emissions of polycyclic aromatic hydrocarbons (PAHs) from both types of MWIs, the PAH removal efficiencies of air-pollution control devices were also included. In this study, the GC/MS technique was used to analyze the concentrations of 21 PAH species contained in the stack flue gas, ESP fly ash, WSB effluent, and incinerating ash. Results show that total-PAHs (i.e., the sum of 21 PAH species) in stack flue gas were dominated by LM-PAHs (i.e., two- to three-ringed PAHs), but in incinerating ash, ESP fly ash and WSB effluent we found that they were dominated by MM-PAHs (i.e., four-ringed PAHs) and HM-PAHs (i.e., five- to seven-ringed PAHs) for both types of MWIs. The above results due to air-pollution control devices used in both types of MWIs had much higher removal efficiencies on both MM-PAHs and HM-PAHs (>78%) than on LM-PAHs (<5%). The emission factors of total-PAHs for MG-MWI (=252,000 ?g/kg-waste) were lower than FG-MWI (=856,000 ?g/kg-waste), which was probably due to more complete combustion involved in the combustion process of the former than the latter. Nevertheless, the above two emission factors were found consistently higher than the only municipal waste incinerator that was located in the same city (=871 ?g/kg-waste, respectively). The above results warrant the need for seeking better technologies for disposing medical waste in the future.

  2. Molecular determinants of hormone mimicry: halogenated aromatic hydrocarbon environmental agents.

    PubMed

    McKinney, J D; Waller, C L

    1998-01-01

    The potential of ostensibly structurally diverse environmental chemicals to modulate endocrine processes in biological systems has been recognized. Difficulty in classifying endocrine system modulators by chemical structure may in large part be due to lack of understanding of mechanisms of action. New developments in understanding nuclear receptor mechanisms of hormone action support a more complex mechanism, possibly involving dimerization/aggregation events leading to multimeric receptor complexes in agonist action. Because of the requirement for high structural specificity in agonist action, it is suggested that most environmental chemicals of concern are likely to function as imperfect hormones with partial agonist-antagonist properties, especially at environmentally realistic concentrations. In the absence of having appropriately placed molecular recognition domains to affect agonist action, partial agonism-antagonism may be associated with favorable low-energy conformational flexibility and complementary receptor protein flexibility. The halogenated aromatic hydrocarbons are of particular concern as hormone mimics since they often have (1) similar molecular recognition factors but in many cases relatively more flexible structures, (2) similar bulk physico-chemical properties controlling uptake and distribution in biological systems, and (3) are relatively more resistant to metabolism and elimination. Some important molecular reactivity properties underlying thyromimetic and estrogenic actions of some of these chemicals are identified and described in terms of structure-activity relationships (SARs). It is proposed that specificity of hormone action in the nucleus could be associated with differential interaction of ligand-bound receptor dimeric forms with other transcription factors specific to the target cell. The small-molecule ligand can be viewed as playing a central, multifunctional role in nuclear receptor action as an organic unmasking and reclustering agent for critical macromolecules. Evidence is discussed in support of a nuclear heterodimerization model for dioxin and related compound action involving a structural transition mechanism. These models with some molecular detail also have utility in understanding the different structural properties of agonists and antagonists. There would appear to be ample opportunities for environmental chemicals to act as antagonists for multiple receptor systems with little more than anchor-ring similarities in structure. The application of three-dimensional quantitative structure-activity (3D QSAR) models incorporating such structural information should be a useful adjunct for identifying endocrine system modulating chemicals. This data has implications for (1) improved drug design, (2) understanding of chemical interaction toxicity, (3) removing undesirable chemicals from our environment, and (4) reducing their chemical release. PMID:9487092

  3. Exposure of firefighters to particulates and polycyclic aromatic hydrocarbons.

    PubMed

    Baxter, C Stuart; Hoffman, Joseph D; Knipp, Michael J; Reponen, Tiina; Haynes, Erin N

    2014-01-01

    Firefighting continues to be among the most hazardous yet least studied occupations in terms of exposures and their relationship to occupational disease. Exposures are complex, involving mixtures of particles and chemicals such as polycyclic aromatic hydrocarbons (PAHs). Adverse health effects associated with these agents include elevated incidences of coronary heart disease and several cancers. PAHs have been detected at fire scenes, and in the firehouse rest area and kitchen, routinely adjoining the truck bay, and where firefighters spend a major part of each shift. An academic-community partnership was developed with the Cincinnati Fire Department with the goal of understanding active firefighters' airborne and dermal PAH exposure. PAHs were measured in air and particulates, and number and mass concentrations, respectively, of submicron (0.02-1 ?m) and PM2.5 (2.5 ?m diameter and less) particles during overhaul events in two firehouses and a University of Cincinnati administrative facility as a comparison location. During overhaul firefighters evaluate partially combusted materials for re-ignition after fire extinguishment and commonly remove Self-Contained Breathing Apparatus (SCBA). Face and neck wipes were also collected at a domestic fire scene. Overhaul air samples had higher mean concentrations of PM2.5 and submicron particles than those collected in the firehouse, principally in the truck bay and kitchen. Among the 17 PAHs analyzed, only naphthalene and acenaphthylene were generally detectable. Naphthalene was present in 7 out of 8 overhaul activities, in 2 out of 3 firehouse (kitchen and truck bay) samples, and in none collected from the control site. In firefighter face and neck wipes a greater number of PAHs were found, several of which have carcinogenic activity, such as benzofluoranthene, an agent also found in overhaul air samples. Although the concentration for naphthalene, and all other individual PAHs, was very low, the potential simultaneous exposure to multiple chemicals even in small quantities in combination with high ultrafine particle exposure deserves further study. It is recommended that personal respiratory and skin protection be worn throughout the overhaul process. PMID:24512044

  4. Intermediates in the Formation of Aromatics in Hydrocarbon Combustion

    NASA Technical Reports Server (NTRS)

    Walch, Stephen P.; Langhoff, S. R. (Technical Monitor)

    1994-01-01

    The formation of the first benzene ring is believed to be the rate limiting step in soot formation. Two different mechanisms have been proposed for formation of cyclic C6 species. The first involves the reaction of two acetylenes to give CH2CHCCH (vinyl acetylene), the loss of a H to give CHCHCCH (n-C41-13) or CH2CCCH (iso-C4H3), and addition of another acetylene to n-C4H3, followed by ring closure to give phenyl radical. Miller and Melius argue that only n-C4H3 leads to phenyl radical and since iso-C4H3 is more stable than n-C4H3 this mechanism is unlikely. An alternative mechanism proposed by them is formation of benzene from the dimerization of two CH2CCH (propargyl) radicals (formed by the reaction of singlet methylene with C2H2). We report reaction pathways and accurate energetics (from CASSCF/internally contracted CI calculations) for the reactions of CH(pi-2) and CH2-1 with acetylene, the reaction of vinylidene with acetylene, and the reaction of n-C4H3 and iso-C4H3 with acetylene. These calculations identify two new reactive intermediates CHCHCH ( a A"-2 ground state in Cs symmetry; spin coupling is a doublet from three singly occupied orbitals) and CHCCH (B-3 ground state in C2 symmetry) from the reaction of CH with acetylene. These species dimerize with no barrier to form benzene and para-benzyne, respectively. CHCCH is proposed as a reactive intermediate which can add to benzene to give higher polynuclear aromatic hydrocarbons or fullerenes. The addition of a C3H2 unit releases two C-C bond energies and thus the resulting addition product contains sufficient energy to break several CH bonds leading to a reduction in the H to C ratio as the cluster size increases. It is found that iso-C4H3 adds to acetylene to initially give a fulvene radical but that this species rearranges to phenyl radical. Thus, the reaction of acetylene with iso-C4H3 does lead to phenyl radical and the cyclization pathway may also contribute to formation of the initial benzene ring.

  5. An Emission Inventory of Polycyclic Aromatic Hydrocarbons in China

    NASA Astrophysics Data System (ADS)

    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 geographical variations. In general, the southeastern provinces of China were characterized by higher emission per capita. The PAHs emissions were higher in the winter than those in the summer. In the following work, the above emission inventory will be used as an input to Chemical Transport Model to simulate the ambient PAHs concentrations in China, and the uncertainty of the inventory will be assessed based on the comparisons between simulated concentrations and available observations. Acknowledgement This work was financially supported by the Natural Science Foundation of China (Grant No. 41175102). Corresponding author: Xuesong Wang

  6. Bioremediation of Mixtures of High Molecular Weight Polycyclic Aromatic Hydrocarbons

    NASA Astrophysics Data System (ADS)

    Xu, H.; Wu, J.; Shi, X.; Sun, Y.

    2014-12-01

    Although bioremediation has been considered as one of the most promising means to remove polycyclic aromatic hydrocarbons (PAHs) from polluted environments, the efficacy of PAHs bioremediation still remains challenged, especially for high molecular weight PAHs (HMW PAHs) and their mixtures. This study was focused on (a) isolation and characterization of pure strain and mixed microbial communities able to degrade HMW PAHs and (b) further evaluation of the ability of the isolated microbes to degrade HMW PAHs mixtures in the absence and presence of indigenous flora. Fluoranthene, benzo[b]fluoranthene and pyrene were selected as the representative HMW PAHs in this study. A pure bacterial strain, identified as Herbaspirillum chlorophenolicum FA1, was isolated from activated sludge. A mixed bacterial community designated as consortium-4 was isolated from petroleum contaminated soils, containing Pseudomonas sp. FbP1?Enterobacter sp. FbP2?Hydrogenophaga sp. FbP3 and Luteolibacter pohnpeiensis. FbP4. To our knowledge, this is the first study to demonstrate that bacterial strains of Herbaspirillum chlorophenolicum FA1 and Luteolibacter pohnpeiensis. FbP4 can also degrade fluoranthene, benzo[b]fluoranthene and pyrene. Experiment results showed that both strain FA1 and consortium-4 could degrade fluoranthene, benzo[b]fluoranthene and pyrene within a wide range of temperature, pH and initial PAHs concentration. Degradation of HMW PAHs mixtures (binary and ternary) demonstrated the interactive effects that can alter the rate and extent of biodegradation within a mixture. The presence of indigenous flora was found to either increase or decrease the degradation of HMW PAHs, suggesting possible synergistic or competition effects. Biodegradation kinetics of HMW PAHs for sole substrates, binary and ternary systems was evaluated, with the purpose to better characterize and compare the biodegradation process of individual HMW PAH and mixtures of HMW PAHs. Results of this study could advance our understanding of HMW PAHs biodegradation and help to develop successful bioremediation strategies. This work was supported by the National Natural Science Foundation of China (41102148), and the Specialized Research Fund for the Doctoral Program of Higher Education of China (20110091120063).

  7. Polycyclic aromatic hydrocarbons in US and Swedish smokeless tobacco products

    PubMed Central

    2013-01-01

    Background Debate about the health implications of using smokeless tobacco products (STPs) has prompted considerable interest in characterising their levels of toxic and carcinogenic components. In the present study seventy smokeless tobacco products from the US and Sweden, categorized as chewing tobacco, dry and moist snuff, hard and soft pellets, plug, and loose and portion snus, were analysed for twenty one polycyclic aromatic hydrocarbons (PAHs). The tested brands represented 80-90% of the 2008 market share for the major STP categories in these two countries. Results There were significant differences in the total and individual PAH concentrations in the different styles of product. Substantially higher levels of total PAHs (10–60 fold) were found in moist and dry snuff and soft pellets than in the other smokeless tobacco styles. The individual PAH concentrations followed the same patterns as total PAHs except for naphthalene, for which the highest concentrations were found in snus and moist snuff. Good correlations were obtained between benzo[a]pyrene (B[a]P) and all the other PAHs except naphthalene, 1-methylnaphthalene and 2-methylnaphthalene, providing evidence for the first time that it can be used as a good marker for PAHs in STPs. Results were generally in good agreement with two previous studies of PAHs in STPs, except for naphthalene for which significantly lower concentrations were found than previously reported. Analysis of the ratios of different PAHs confirmed that the use of fire-cured tobaccos in the snuffs and soft pellet were the major source of PAHs in these product styles, and provided, for the first time, some indications as to the source of PAHs in the other STP styles, including petrogenic and other combustion sources. Conclusions This study confirms the presence of PAHs in STPs, and identifies substantial differences between the levels in different STP categories. Since previous studies of naphthalene concentrations in STPs differed so markedly from those found in this study, it is recommended that further work on PAH determination is undertaken to investigate the source of this discrepancy. PMID:24011230

  8. Polycyclic aromatic hydrocarbons in the South American environment.

    PubMed

    Barra, Ricardo; Castillo, Caroline; Torres, Joao Paulo Machado

    2007-01-01

    Pollution of the environment with polycyclic aromatic hydrocarbons (PAHs) should be a global concern, especially in urbanized areas. In South American countries, where notable increase in urban populations has been observed in the past few years, reliable information about the pollution status of these urban environments is not always easily accessible, and therefore an effort to collect updated information is required. This review attempts to contribute by analyzing the existing information regarding environmental levels of PAHs in some South American countries. A regional trend for environmental PAH information is an uneven contribution, because some countries, such as Bolivia, Peru, Paraguay, and Ecuador, have reported no information at all in the scientific literature, reflecting to a certain extent the different patterns of economic, technical, and scientific development. PAH air monitoring is one of the areas that has received the most attention during the last few years, mainly in Brazil, Chile, and Argentina, where data represent a few geographical areas within the region. PAH levels in air from some urban areas in Argentina, Brazil, and Chile, considered moderate to high (100-1000ng/m3), are probably among the highest values reported in the open literature. Urbanization, vehicle pollution, and wood fires are the principal contributors to the high reported levels. In more temperate areas, a clear distinction is observed between summer and winter levels. PAH monitoring in soils is very limited within the region, with few data available, and most information indicates widespread pollution. In Brazil, values for many representative ecosystems were found. In Chile, data from forestry and agricultural areas indicate in general low concentrations, in spite of a relatively high detection frequency. Pollution levels in soils are highly dependent on their closeness to PAH sources and certain cultural practices (agricultural burnings, forest fires, etc.). Water PAH levels are rarely reported in the scientific literature for South American countries. Few data were available, even though many regulatory agencies perform routine analysis of hydrocarbons in waters. No information was found specifically related to PAH compounds, which could indicate generally low PAH levels in waters. Regional PAH information for sediments also indicates higher levels. Overall, as observed for water, sediment data indicate a complex situation in densely populated areas affected by urban-industrial inputs where high PAH levels are found. In contrast, in remote areas a typical profile of diagenetic PAHs dominates. Concentrations are greatly variable and are principally related to several highly contaminated sites in Argentina and Brazil (hot spots) with levels four to five orders of magnitude higher. Even though PAHs have carcinogenic properties, little attention has been paid to the analysis of aquatic organisms except in the case of bivalves. As observed for other environmental receptors, the regional data distribution is uneven and is heavily centered in coastal environments and in a few countries (Argentina, Brazil, Chile, and Peru). The most comprehensive PAH monitoring program in the South American coastal environment is the Mussel Watch. Baseline PAH concentrations range from 200 to 700 microg kg(-1) lipids in unpolluted sites; from 1,000 to 3,000 microg kg(-1) in moderately contaminated sites; and from 4,000 to 13,000 microg/kg lipids in the most affected bivalves that come from areas of Río de la Plata (Argentine side), Recife (Brazil), and Punta Arenas (Chile). Critical data gaps exist with respect to PAH analysis in biota, including humans, in foodstuffs, and subsequent effects. Considering the high levels reported in the air compartment, risk assessment procedures in highly populated areas need to be performed. Additionally, few countries within the region have information on PAH levels. In these countries, this type of analysis needs to be performed, and the laboratory capacity needs to be built to assure the accomplishment of these

  9. C-Nucleosides Derived from Simple Aromatic Hydrocarbons

    PubMed Central

    Chaudhuri, Narayan C.; Ren, Rex X.-F.

    2009-01-01

    We describe the synthesis, structure and DNA incorporation of a class of novel aromatic C-deoxynucleosides in which benzenes and larger polycyclic aromatics serve as DNA base analogs. Novel approaches have been developed for glycosidic bond formation and for epimenzation of the anomeric substitutents to ?-configuration, and we describe some of the properties of such compounds in DNA. PMID:20336193

  10. Polycyclic aromatic hydrocarbons in sediments and mussels of the western Mediterranean Sea

    SciTech Connect

    Baumard, P.; Budzinski, H.; Garrigues, P. [Univ. Bordeaux I, Talence (France)

    1998-05-01

    The distribution of polycyclic aromatic hydrocarbons (PAHs) has been investigated in superficial sediments and mussels (Mytilus galloprovincialis) of the western Mediterranean sea. The analyses were performed by gas chromatography coupled to mass spectrometry (GC-MS). The PAH concentrations ranged from 1 to 20,500 ng/g in the sediments. Different molecular indices allowed differentiation between the different pollutant sources. On the French coast, PAHs originated mainly from incomplete combustion of organic matter (pyrolytic origin), whereas for some sites in Corsica and Sardinia an overimposition of petrogenic PAHs occurred. The mussel PAH concentrations ranged from 25 to 390 ng/g. The total and individual PAH bioaccumulation factors were calculated. The correlation between sediment and mussel PAH content was discussed in terms of bioavailability. It was possible to distinguish different absorption routes for the xenobiotics according to their physicochemical properties. Because the mussel distribution of phenanthrene and anthracene seems to be governed by their water solubility, these compounds were probably mainly absorbed as the water-dissolved form, whereas the heavier molecular weight PAHs (more than four aromatic rings), whose sediment and mussel concentrations are correlated with higher correlation coefficients than for phenanthrene and anthracene, were probably mainly absorbed as adsorbed on particles. Furthermore, a possible preferential biotransformation of benzo[a]pyrene over benzo[e]pyrene is discussed.

  11. Absorption of nitro-polycyclic aromatic hydrocarbons by biomembrane models: effect of the medium lipophilicity.

    PubMed

    Castelli, Francesco; Micieli, Dorotea; Ottimo, Sara; Minniti, Zelica; Sarpietro, Maria Grazia; Librando, Vito

    2008-10-01

    To demonstrate the relationship between the structure of nitro-polycyclic aromatic hydrocarbons and their effect on biomembranes, we have investigated the influence of three structurally different nitro-polycyclic aromatic hydrocarbons, 2-nitrofluorene, 2,7-dinitrofluorene and 3-nitrofluoranthene, on the thermotropic behavior of dimyristoylphosphatidylcholine multilamellar vesicles, used as biomembrane models, by means of differential scanning calorimetry. The obtained results indicate that the studied nitro-polycyclic aromatic hydrocarbons affected the thermotropic behavior of multilamellar vesicles to various extents, modifying the pretransition and the main phase transition peaks and shifting them to lower temperatures. The effect of the aqueous and lipophilic medium on the absorption process of these compounds by the biomembrane models has been also investigated revealing that the process is hindered by the aqueous medium but strongly allowed by the lipophilic medium. PMID:18723205

  12. Non-linear, cata-Condensed, Polycyclic Aromatic Hydrocarbon Materials: A Generic Approach and Physical Properties.

    PubMed

    Haire, Barnaby T; Heard, Kane W J; Little, Mark S; Parry, Adam V S; Raftery, James; Quayle, Peter; Yeates, Stephen G

    2015-07-01

    A generic approach to the regiospecific synthesis of halogenated polycyclic aromatics is made possible by the one- or two-directional benzannulation reactions of readily available (ortho-allylaryl)trichloroacetates (the "BHQ" reaction). Palladium-catalysed cross-coupling reactions of the so-formed haloaromatics enable the synthesis of functionalised polycyclic aromatic hydrocarbons (PAHs) with surgical precision. Overall, this new methodology enables the facile mining of chemical space in search of new electronic functional materials. PMID:26059760

  13. GC\\/MS analysis of polynuclear aromatic hydrocarbons in sediment samples from the Niger Delta region

    Microsoft Academic Search

    Chimezie Anyakora; Anthony Ogbeche; Pete Palmer; Herbert Coker; Grace Ukpo; Celina Ogah

    2005-01-01

    Thirteen sediment samples from different locations in the Niger Delta region of Nigeria were analyzed for the presence of 16 polynuclear aromatic hydrocarbons (PAHs) via gas chromatography\\/mass spectrometry. The specific target compounds for this study included naphthalene, acenaphthylene, acenaphthene, flourene, phenanthrene, anthracene, flouranthene, pyrene, benz[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]flouranthene, benzo[a]pyrene, benzo[ghi]perylene, dibenz[a,h]anthracene, and indeno[1,2,3-cd]pyrene. Four isotopically labeled polynuclear aromatic hydrocarbons (acanaphthene-d10,

  14. Polycyclic aromatic hydrocarbons profiles of spent drilling fluids deposited at Emu-Uno, Delta State, Nigeria.

    PubMed

    Iwegbue, Chukwujindu M A

    2011-10-01

    The concentrations and profiles of polycyclic aromatic hydrocarbons were determined in spent drilling fluid deposited at Emu-Uno, Delta State of Nigeria. The total concentrations of polycyclic aromatic hydrocarbons in the spent drilling fluid deposits ranged between 40 and 770 ?g kg(-1). The PAHs profile were predominantly 2- and 3-rings with acenaphthalene, phenanthrene, fluorene being the predominant PAHs. The prevalence of 2- and 3-rings PAHs in the spent drilling fluid deposits indicate contamination of the drilling fluids with crude oil during drilling. Incorporation of spent drilling fluids into the soil has serious implication for soil, surface water and groundwater quality. PMID:21809098

  15. Determination of low level exposure to volatile aromatic hydrocarbons and genotoxic effects in workers at a styrene plant

    Microsoft Academic Search

    O Holz; G Scherer; S Brodtmeier; F Koops; K Warncke; T Krause; A Austen; J Angerer; A R Tricker; F Adlkofer

    1995-01-01

    OBJECTIVES--Low exposures to volatile aromatic hydrocarbons and cytogenetic effects in peripheral white blood cells were determined in 25 healthy workers employed in different areas of a styrene production plant in the former German Democratic Republic. The results were compared with 25 healthy unexposed controls (matched for age and sex) employed in the same company. METHODS--The concentrations of aromatic hydrocarbons determined

  16. The cytotoxicity of jet fuel aromatic hydrocarbons and dose-related interleukin-8 release from human epidermal keratinocytes

    Microsoft Academic Search

    C. C. Chou; J. E. Riviere; N. A. Monteiro-Riviere

    2003-01-01

    Many jet fuel aromatic hydrocarbons are known carcinogens with the ability to both readily penetrate the skin with high absorptive flux and cause skin irritation. In order to evaluate the in vitro cutaneous toxicity of individual aromatic hydrocarbons in jet fuels and their potential for inducing skin irritation, we evaluated the LD 50, the highest non-cytotoxic (5% mortality) dose (HNTD),

  17. Polycyclic aromatic hydrocarbons (PAH) and phenolic substances in meat products smoked with different types of wood and smoking spices.

    PubMed

    Hitzel, Alexander; Pöhlmann, Margarete; Schwägele, Fredi; Speer, Karl; Jira, Wolfgang

    2013-08-15

    The contents of polycyclic aromatic hydrocarbons (15+1 EU PAH) and phenolic substances (guaiacol, 4-methylguaiacol, syringol, eugenol, and trans-isoeugenol) were investigated in smouldering-smoked Frankfurters and mini-salamis. For the 51 smoking experiments wood chips of oak, poplar, hickory, spruce, fir, alder, beech, and beech with an apple-smoking spice mix, cherry-smoking spice mix, and a mix of juniper berries and bay leaves were tested. The use of poplar and hickory led to a decrease in the PAH contents in the range of 35-55% compared to the commonly used beech wood. Higher PAH contents by using softwood were not observed. The use of the rapidly growing poplar seems to be a reasonable approach for reducing the PAH contents in smoked meat products. Furthermore, the sum contents of the five phenolic substances in sausages smoked with poplar were higher, or only slightly lower, when compared to the use of beech. PMID:23561196

  18. High-resolution electron spectroscopy, preferential metal-binding sites, and thermochemistry of lithium complexes of polycyclic aromatic hydrocarbons

    NASA Astrophysics Data System (ADS)

    Lee, Jung Sup; Krasnokutski, Serge A.; Yang, Dong-Sheng

    2011-01-01

    Polycyclic aromatic hydrocarbons are model systems for studying the mechanisms of lithium storage in carbonaceous materials. In this work, Li complexes of naphthalene, pyrene, perylene, and coronene were synthesized in a supersonic metal-cluster beam source and studied by zero-electron-kinetic-energy (ZEKE) electron spectroscopy and density functional theory calculations. The adiabatic ionization energies of the neutral complexes and frequencies of up to nine vibrational modes in the singly charged cations were determined from the ZEKE spectra. The metal-ligand bond energies of the neutral complexes were obtained from a thermodynamic cycle. Preferred Li/Li+ binding sites with the aromatic molecules were determined by comparing the measured spectra with theoretical calculations. Li and Li+ prefer the ring-over binding to the benzene ring with a higher ?-electron content and aromaticity. Although the ionization energies of the Li complexes show no clear correlation with the size of the aromatic molecules, the metal-ligand bond energies increase with the extension of the ?-electron network up to perylene, then decrease from perylene to coronene. The trends in the ionization and metal-ligand bond dissociation energies of the complexes are discussed in terms of the orbital energies, local quadrupole moments, and polarizabilities of the free ligands and the charge transfer between the metal atom and aromatic molecules.

  19. Estrogenic activity of environmental polycyclic aromatic hydrocarbons in uterus of immature Wistar rats

    Microsoft Academic Search

    Vladimír Kummer; Jarmila Mašková; Zden?k Zralý; Ji?í Ne?a; Pavlína Šime?ková; Jan Vondrá?ek; Miroslav Machala

    2008-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are an important group of environmental pollutants, known for their mutagenic and carcinogenic activities. Many PAHs are aryl hydrocarbon receptor (AhR) ligands and several recent studies have suggested that PAHs or their metabolites may activate estrogen receptors (ER). The present study investigated possible estrogenic\\/antiestrogenic effects of abundant environmental contaminants benzo[a]pyrene (BaP), benz[a]anthracene (BaA), fluoranthene (Fla) and

  20. Polycyclic aromatic hydrocarbons in fish from remote and high mountain lakes in Europe and Greenland.

    PubMed

    Vives, I; Grimalt, J O; Fernández, P; Rosseland, B

    2004-05-25

    Polycyclic aromatic hydrocarbons (PAHs) were analysed in liver of fifty-seven individual trout distributed among seven high mountain lakes in Europe and one remote lake in Greenland. In all cases, very similar distributions were observed in which phenanthrene largely predominated and fluoranthene and pyrene were the second major compounds. These distributions were similar to those observed in the dissolved fraction of the waters studied in three of these lakes. The range of concentrations of PAH in fish liver show only a five-fold variation, which is considerably smaller than the range more than two orders of magnitude of sedimentary PAH concentrations of these lakes. No correlation between PAH content in sediments and fish liver has been found both at the level of total and individual compounds. However, lake site is the main statistically significant factor of variability between PAH concentrations in fish liver. Changes in fish species explain significant differences in liver content of some PAHs. Within lake, condition factor and liver concentration are inversely correlated. Female fish display lower average concentrations than male in all lakes but the differences are not statistically significant. No correspondence between fish age and PAH content has been observed. PMID:15081697

  1. Surface enhanced Raman spectroscopy of polycyclic aromatic hydrocarbons and molecular asphaltenes

    NASA Astrophysics Data System (ADS)

    Andrews, A. Ballard; Wang, Dongxing; Marzec, Katarzyna M.; Mullins, Oliver C.; Crozier, Kenneth B.

    2015-01-01

    We describe, for the first time to the best of our knowledge, the acquisition of surface enhanced Raman spectra (SERS) of asphaltenes. SERS is an especially sensitive probe for aromatic carbon making it ideal to investigate the enigmatic polycyclic aromatic hydrocarbons (PAHs) of asphaltenes, the heaviest, most aromatic components of crude oil. SERS spectra of a known PAH model compound and of asphaltene samples are compared to density functional theory (DFT) calculations of PAH structures. This combination of experimental and theoretical methods represents an advance in the characterization of asphaltenes and other complex mixtures.

  2. Enumeration and characterization of the soil microflora from hydrocarbon-contaminated soil sites able to mineralize polycyclic aromatic hydrocarbons (PAH)

    Microsoft Academic Search

    M. Kästner; M. Breuer-Jammali; B. Mahro

    1994-01-01

    The use of a plate screening technique allowed the direct isolation and quantification of polycylic aromatic hydrocarbon (PAH)-degrading bacteria from different soil sites. Bacteria that were able to grow on anthracene, phenanthrene, fluoranthene or pyrene as a sole carbon source were found with numbers between 103 and 105 colony-forming units (cfu)\\/g of soil dry weight, but only in samples that

  3. CHEMICAL CHARACTERIZATION OF POLYNUCLEAR AROMATIC HYDROCARBON DEGRADATION PRODUCTS FROM SAMPLING ARTIFACTS

    EPA Science Inventory

    The objective of the study was to characterize the polar components, mainly polynuclear aromatic hydrocarbon (PAH) derivatives, in air samples and to determine whether these compounds are from sampling artifacts or from the sampled air. A literature survey was conducted to review...

  4. REMOVAL OF POLYNUCLEAR AROMATIC HYDROCARBONS FROM PRIMARY ALUMINUM AIR POLLUTION CONTROL SCRUBBER WASTEWATER

    EPA Science Inventory

    A pilot-scale study was conducted at a primary aluminum plant to evaluate the removal of benzo(a)pyrene and other polynuclear aromatic hydrocarbons (PAH's) from potline scrubber wastewater. Specific objectives included determining the need for granular activated carbon to remove ...

  5. Risk of polycyclic aromatic hydrocarbon (PAH) exposure from ingested food: The Azerbaijan case study

    Microsoft Academic Search

    Oke C. Nwaneshiudu; Robin L. Autenrieth; Thomas J. McDonald; Kirby C. Donnelly; Erica D. Degollado; Afraa A. Abusalih

    2007-01-01

    Risks due to polycyclic aromatic hydrocarbons (PAHs) exposure from food consumption for the population of Azerbaijan were determined using deterministic and probabilistic methods. The guidelines and methods described and presented in the United States Environmental Protection Agency (U.S. EPA) Risk Assessment Guidance for Superfund (RAGS) Part A was used in performing the risk assessments. The current study utilized concentration data

  6. Modeling of nitro-polycyclic aromatic hydrocarbon formation and decay in the atmosphere

    Microsoft Academic Search

    Zhihua Fan; Danhua Chen; Parag Birla; Richard M. Kamens

    1995-01-01

    A reaction mechanism of polycyclic aromatic hydrocarbons (PAH) and nitro-PAH (NPAH) in the gas and particle phase in the atmosphere has been further evaluated and modified using outdoor smog chamber experimental results. Diesel exhaust emissions were added to a 190 m3 outdoor smog chamber and permitted to age under conditions of daylight and darkness. A sampling train consisting of an

  7. Toxicity of polycyclic aromatic hydrocarbons. (Latest citations from Pollution abstracts). Published Search

    SciTech Connect

    NONE

    1995-07-01

    The bibliography contains citations concerning the toxicity and biochemical effects of aromatic polycyclic hydrocarbons. Citations discuss air, water, soil, and sediment pollution and control. Topics include vehicle emissions and control, pollutant pathways, carcinogens and mutagenic activity, and photoinduced toxicity. Food contamination, environmental monitoring, and soil contamination along highways are examined. (Contains 50-250 citations and includes a subject term index and title list.)

  8. COMPARISON OF QUANTUM MECHANICAL METHODS TO COMPUTE THE BIOLOGICALLY RELEVANT REACTIVITIES OF CYCLOPENTA POLYCYCLIC AROMATIC HYDROCARBONS

    EPA Science Inventory

    In computational studies to understand the interaction of polycyclic aromatic hydrocarbons (PAHS) with biomolecular systems, the semi-empirical method AM1 has been used to determine the geometry of the PAH, its metabolites and relevant intermediates. umber of studies have shown t...

  9. Coal-tar-based pavement sealcoat, polycyclic aromatic Hydrocarbons (PAHs), and environmental health

    USGS Publications Warehouse

    Mahler, B.J.; Van Metre, P.C.

    2011-01-01

    Studies by the U.S. Geological Survey (USGS) have identified coal-tar-based sealcoat-the black, viscous liquid sprayed or painted on asphalt pavement such as parking lots-as a major source of polycyclic aromatic hydrocarbon (PAH) contamination in urban areas for large parts of the Nation. Several PAHs are suspected human carcinogens and are toxic to aquatic life.

  10. Determination of polycyclic aromatic hydrocarbons in alcoholic drinks and the identification of their potential sources

    Microsoft Academic Search

    M. S. García-Falcón; J. Simal-Gándara

    2005-01-01

    Some polycyclic aromatic hydrocarbons (PAHs), particularly those with a high molecular mass, have been classified as probably being carcinogenic to humans by the International Agency for Research on Cancer (IARC). The significance of the determination of PAHs is reflected by the special attention the European Union is paying to regulating their maximum allowed levels in various types of foodstuffs. Like

  11. Polycyclic aromatic hydrocarbons in edible fats and oils: occurrence and analytical methods

    Microsoft Academic Search

    Sabrina Moret; Lanfranco S Conte

    2000-01-01

    This review deals with analytical methods for polycyclic aromatic hydrocarbon (PAH) determination in oils and fats. The data reported in the introduction deal with PAH dietary intake from this group of food and contamination levels recently found by some authors in different vegetable oils, stressing the importance of establishing a method suitable for routine analyses. Traditional sample preparation relies on

  12. EXTRACTION AND DETERMINATION OF SELECTED POLYCYCLIC AROMATIC HYDROCARBONS IN PLANT TISSUES

    EPA Science Inventory

    A procedure has been developed for analysis of plant material for polycyclic aromatic hydrocarbons (PAHs). Sonication is used to extract the PAHs from homogenized plant material into acetonitrile and then the PAHs are partitioned into pentane. The pentane extract is fractionated ...

  13. Enumeration and phylogenetic analysis of polycyclic aromatic hydrocarbon-degrading marine bacteria from Puget Sound sediments

    SciTech Connect

    Geiselbrecht, A.D.; Herwig, R.P.; Deming, J.W.; Staley, J.T. [Univ. of Washington, Seattle, WA (United States)

    1996-09-01

    Polycyclic aromatic hydrocarbons (PAHs) are primarily released into the environment through anthropomorphic sources. PAH degradation has been known to occur in marine sediments. This paper describes the enumeration, isolation, and preliminary characterization of PAH-degrading strains from Puget Sound sediments. 38 refs., 3 figs., 3 tabs.

  14. Comparison of various extraction techniques for the determination of polycyclic aromatic hydrocarbons in worms

    Microsoft Academic Search

    D. Mooibroek; R. Hoogerbrugge; B. H. G. Stoffelsen; E. Dijkman; C. J. Berkhoff; E. A. Hogendoorn

    2002-01-01

    Two less laborious extraction methods, viz. (i) a simplified liquid extraction using light petroleum or (ii) microwave-assisted solvent extraction (MASE), for the analysis of polycyclic aromatic hydrocarbons (PAHs) in samples of the compost worm Eisenia andrei, were compared with a reference method. After extraction and concentration, analytical methodology consisted of a cleanup of (part) of the extract with high-performance gel

  15. WARM DUST AND SPATIALLY VARIABLE POLYCYCLIC AROMATIC HYDROCARBON EMISSION IN THE DWARF STARBURST GALAXY NGC 1705

    E-print Network

    Draine, Bruce T.

    extinction at optical wavelengths. The galaxy has a relatively low global dust mass ($2 ; 105 M, implying a global dust-to-gas mass ratio $2­4 times lower than the Milky Way average, roughly consistentWARM DUST AND SPATIALLY VARIABLE POLYCYCLIC AROMATIC HYDROCARBON EMISSION IN THE DWARF STARBURST

  16. TECHNICAL BASIS FOR NARCOTIC CHEMICALS AND POLYCYCLIC AROMATIC HYDROCARBON CRITERIA. II. MIXTURES AND SEDIMENTS

    Microsoft Academic Search

    Dominic M. Di Toro; Joy A. McGrath

    2000-01-01

    A method is presented for developing sediment quality guidelines (SQG) for narcotic chemicals in general and polycyclic aromatic hydrocarbons (PAHs) in particular. The guidelines can be applied to any individual or mixture of narcotic chemicals including PAHs using only the chemical's octanol\\/water partition coefficient. They are derived using the final chronic values for type I narcotics developed from a database

  17. Occurrence and Phylogenetic Diversity of Sphingomonas Strains in Soils Contaminated with Polycyclic Aromatic Hydrocarbons

    Microsoft Academic Search

    Natalie M. E. J. Leys; Annemie Ryngaert; Leen Bastiaens; Willy Verstraete; Eva M. Top; Dirk Springael

    2004-01-01

    Bacterial strains of the genus Sphingomonas are often isolated from contaminated soils for their ability to use polycyclic aromatic hydrocarbons (PAH) as the sole source of carbon and energy. The direct detection of Sphingomonas strains in contaminated soils, either indigenous or inoculated, is, as such, of interest for bioremediation purposes. In this study, a culture-independent PCR-based detection method using specific

  18. WATERSHED-BASED SOURCES OF POLYCYCLIC AROMATIC HYDROCARBONS IN URBAN STORM WATER

    Microsoft Academic Search

    Eric D. Stein; Liesl L. Tiefenthaler; Kenneth Schiff

    2006-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic and mutagenic compounds, ubiquitous in the air and water of urban environments, and have been shown to accumulate in coastal estuarine and marine sediments. Although previous studies have documented concentrations and loads of PAHs in urban runoff, little is known about the sources and temporal patterns of PAH loading from storm water. This study

  19. Estimation of individual dermal and respiratory uptake of polycyclic aromatic hydrocarbons in 12 coke oven workers

    Microsoft Academic Search

    J G VanRooij; M M Bodelier-Bade; F J Jongeneelen

    1993-01-01

    Twelve workers from a coke plant in The Netherlands participated in an intensive skin monitoring programme combined with personal air sampling and biological monitoring during five consecutive eight hour workshifts. The purpose of the study was to make a quantitative assessment of both the dermal and respiratory intake of polycyclic aromatic hydrocarbons (PAHs). Pyrene was used as a marker compound

  20. CHARACTERIZATION OF EMISSIONS OF PAH'S (POLYNUCLEAR AROMATIC HYDROCARBON) FROM RESIDENTIAL COAL-FIRED SPACE HEATERS

    EPA Science Inventory

    The paper gives results of a joint emissions testing and analysis program--the U.S. EPA and the State of Vermont--to determine polynuclear aromatic hydrocarbon (PAH), particulate, sulfur dioxide (SO2), and carbon monoxide (CO) emissions from two coal-fired residential space heate...

  1. Fluorescence, Absorption, and Excitation Spectra of Polycyclic Aromatic Hydrocarbons as a Tool for Quantitative Analysis

    ERIC Educational Resources Information Center

    Rivera-Figueroa, A. M.; Ramazan, K. A.; Finlayson-Pitts, B. J.

    2004-01-01

    A quantitative and qualitative study of the interplay between absorption, fluorescence, and excitation spectra of pollutants called polycyclic aromatic hydrocarbons (PAHs) is conducted. The study of five PAH displays the correlation of the above-mentioned properties along with the associated molecular changes.

  2. Applications and New Developments in Fluorescence Spectroscopic Techniques for the Analysis of Polycyclic Aromatic Hydrocarbons

    Microsoft Academic Search

    Digambara Patra

    2003-01-01

    Carcinogenic, mutagenic and the toxic nature of polycyclic aromatic hydrocarbons (PAHs) make them of current interest for environmental monitoring. Recent progress in the use of a fiber optic wave-guide for remote sensing and inexpensive laser sources to enhance sensitivity has made fluorescence techniques rich for PAHs classification and estimation. This is further boosted by multiparametric information e.g., spectral change, intensity,

  3. HIGH PURITY PNA HYDROCARBONS AND OTHER AROMATIC COMPOUNDS. SYNTHESIS AND PURIFICATION

    EPA Science Inventory

    The synthesis and/or purification of a group of polynuclear aromatic (PNA) hydrocarbons, commonly found as pollutants in the environment, are described. The steps used in a given synthesis, the experiments carried out, and a presentation of some instrumental data obtained in esta...

  4. POLYCYCLIC AROMATIC HYDROCARBON BIODEGRADATION AS A FUNCTION OF OXYGEN TENSION IN CONTAMINATED SOIL

    EPA Science Inventory

    Laboratory tests were conducted to determine the effect of soil gas oxygen concentration on the degradation and mineralization of spiked 14C-pyrene and nonspiked 16 priority pollutant polycyclic aromatic hydrocarbons (PAH) present in the soil. The soil used for the evaluation was...

  5. MEASUREMENTS OF POLYCYCLIC AROMATIC HYDROCARBONS IN AMBIENT AIR PARTICULATES IN NORTHERN NEW ENGLAND

    EPA Science Inventory

    The paper gives results of measuring polycyclic aromatic hydrocarbons (PAHs) in ambient air particulates in Northern New England. Standard high-volume filter samples of ambient-air particulates were collected during several heating seasons in a semi-rural village, a rural area, a...

  6. Polycyclic aromatic hydrocarbons and polychlorinated biphenyls in urban soils from Kathmandu, Nepal

    Microsoft Academic Search

    B. Aichner; B. Glaser; W. Zech

    2007-01-01

    Kathmandu, the capital of Nepal, faces increasing environmental problems such as heavy air pollution and lack of proper waste management. The aim of this study was to examine if the soils are also affected by pollution, with the focus on polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). The sum of 20 PAHs in surface soils ranged between 184 and

  7. Polycyclic aromatic hydrocarbons in dust from computers : one possible indoor source of human exposure

    Microsoft Academic Search

    Yu Ren; Tiantao Cheng; Jianmin Chen

    2006-01-01

    Computer is an important part of our usual life and work. The harmful exposure to the radiation of computers has been paid attention broadly. However, chemical pollution related to computers is rarely reported. Here we investigated the levels and sources of EPA 16 priority polycyclic aromatic hydrocarbons (PAHs) in dust samples collected from components and internal walls of computers’ boxes

  8. Partitioning and desorption behavior of polycyclic aromatic hydrocarbons from disparate sources

    Microsoft Academic Search

    W. R. Reeves; T. J. McDonald; L. Cizmas; K. C. Donnelly

    2004-01-01

    Contaminated sediments pose a unique challenge for risk assessment or remediation because the overlying water column may transport contaminants offsite or to ecological receptors. This research compares the behavior of polycyclic aromatic hydrocarbons (PAHs) on marine sediments from two sites. The first site was affected by shipping activities and the second was impacted by a creosote seep. Organic carbon:water partitioning

  9. SOLAR RADIATION DOSE AND PHOTOTOXICITY OF POLYCYCLIC AROMATIC HYDROCARBONS: A CASE STUDY

    EPA Science Inventory

    The toxicity of polycyclic aromatic hydrocarbons increases by as much as three orders of magnitude in the presence of solar radiation. The risk of this photoactive toxicity is thus based on both tissue concentrations of potentially photo activated compounds and the levels of subs...

  10. Factors influencing polycyclic aromatic hydrocarbon distributions in South Carolina estuarine sediments

    Microsoft Academic Search

    John R. Kucklick; Scott K. Sivertsen; Marion Sanders; Geoffrey I. Scott

    1997-01-01

    Surface (2 cm) sediment was collected from three South Carolina estuaries, Winyah Bay, Charleston Harbor and the North Edisto River estuary for a total of 64 samples. The sediment samples were analyzed for 24 individual polycyclic aromatic hydrocarbons (PAHs; two to six rings) by gas chromatography with ion trap mass spectrometric detection. Concentrations of total PAHs were extremely variable, ranging

  11. Induction of nuclear anomalies in the gastrointestinal tract by polycyclic aromatic hydrocarbons

    Microsoft Academic Search

    T. V. Reddy; J. A. Stober; G. R. Olson; F. B. Daniel

    1991-01-01

    A selective list of polycyclic aromatic hydrocarbons (PAH) with varied carcinogenic and mutagenic potencies, which are identified as common contaminants at industrial sites and which often contaminate the neighboring ground water, are investigated for their ability to induce nuclear anomalies (NA) in the mouse gastrointestinal (G.I.) tract. These studies examined the hypothesis that a relationship between NA induction and carcinogenic

  12. Sexual Maturation in Relation to Polychlorinated Aromatic Hydrocarbons: Sharpe and Skakkebaek's Hypothesis Revisited

    Microsoft Academic Search

    Elly Den Hond; Harry A. Roels; Karel Hoppenbrouwers; Tim Nawrot; Lutgarde Thijs; Corinne Vandermeulen; Gerhard Winneke; Dirk Vanderschueren; Jan A. Staessen

    2002-01-01

    Polychlorinated aromatic hydrocarbons (PCAHs) have been described as endocrine disruptors in animals and in accidentally or occupationally exposed humans. In the present study we examined the effect of moderate exposure to PCAHs on sexual maturation. Two hundred adolescents (mean age, 17.4 years) who resided in two polluted suburbs and a rural control area in Flanders (Belgium) participated. We measured the

  13. Characterization of a Polycyclic Aromatic Hydrocarbon–Degrading Microbial Consortium from a Petrochemical Sludge Landfarming Site

    Microsoft Academic Search

    Rodrigo J. S. Jacques; Benedict C. Okeke; Fatima M. Bento; Maria C. R. Peralba; Flávio A. O. Camargo

    2007-01-01

    Anthracene, phenanthrene, and pyrene are polycyclic aromatic hydrocarbon (PAHs) that display both mutagenic and carcinogenic properties. They are recalcitrant to microbial degradation in soil and water due to their complex molecular structure and low solubility in water. This study presents the characterization of an efficient PAH (anthracene, phenanthrene, and pyrene)-degrading microbial consortium, isolated from a petrochemical sludge landfarming site. Soil

  14. Polycyclic aromatic hydrocarbons, black carbon, and molecular markers in soils of Switzerland

    Microsoft Academic Search

    Thomas D. Bucheli; Franziska Blum; André Desaules; Örjan Gustafsson

    2004-01-01

    Polycyclic aromatic hydrocarbons (PAH) were analysed in 23 soil samples (0–10 cm layer) from the Swiss soil monitoring network (NABO) together with total organic carbon (TOC) and black carbon (BC) concentration, as well as some PAH source diagnostic ratios and molecular markers. The concentrations of the sum of 16 EPA priority PAHs ranged from 50 to 619 ?g\\/kg dw. Concentrations

  15. POLYCYCLIC AROMATIC HYDROCARBON FORMATION IN OPPOSED FLOW DIFFUSION FLAMES OF ETHANE. (R825412)

    EPA Science Inventory

    Abstract The effect of fuel-side carbon density on the levels of polycyclic aromatic hydrocarbon (PAH) formation in atmospheric pressure, opposed flow, ethane diffusion flames has been studied using heated micro-probe sampling and gas chromatography/mass spectrometry (...

  16. Determination of polycyclic aromatic hydrocarbons in biochar and biochar amended soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A method for the determination of the 16 USEPA polycyclic aromatic hydrocarbons (PAHs) in biochar and soil amended with biochar was developed. Samples were Soxhlet extracted with acetone:cyclohexane 1:1, and PAHs were analysed by GC-MS after silica gel clean-up. In a comparative study based on reflu...

  17. Assessment of exposure to polycyclic aromatic hydrocarbons in engine rooms by measurement of urinary 1-hydroxypyrene

    Microsoft Academic Search

    B E Moen; R Nilsson; R Nordlinder; S Ovrebø; K Bleie; A H Skorve; B E Hollund

    1996-01-01

    OBJECTIVE: Machinists have an increased risk of lung cancer and bladder cancer, and this may be caused by exposure to carcinogenic compounds such as asbestos and polycyclic aromatic hydrocarbons (PAHs) in the engine room. The aim of this study was to investigate the exposure of engine room personnel to PAHs, with 1-hydroxypyrene in urine as a biomarker. METHODS: Urine samples

  18. Cancer risk from occupational and environmental exposure to polycyclic aromatic hydrocarbons

    Microsoft Academic Search

    Paolo Boffetta; Nadia Jourenkova; Per Gustavsson

    1997-01-01

    Epidemiologic evidence on the relationship between polycyclic aromatic hydrocarbons (PAH) and cancer is reviewed. High occupational exposure to PAHs occurs in several industries and occupations. Covered here are aluminum production, coal gasification, coke production, iron and steel foundries, tar distillation, shale oil extraction, wood impregnation, roofing, road paving, carbon black production, carbon electrode production, chimney sweeping, and calcium carbide production.

  19. Detection of polycyclic aromatic hydrocarbons in skin oil obtained from roofing workers

    Microsoft Academic Search

    M. S. Wolff; B. Taffe; R. R. Boesch; I. J. Selikoff

    1982-01-01

    Many sources of polyclic aromatic hydrocarbons (PAH), which constitute potential human exposures, have been documented, including urban air, cigarette smoke, heavily contaminated petroleum derivatives, and even topical medications. The implication of potential human health effects has been extrapolated from extensive data on animal carcinogenesis of PAH. Thirteen PAH compounds have been documented as potential carcinogens, including 7 of the 12

  20. Phototoxic response of Lumbriculus variegatus to sediments contaminated by polycyclic aromatic hydrocarbons

    Microsoft Academic Search

    Philip D. Monson; Gerald T. Ankley; Patricia A. Kosian

    1995-01-01

    The toxicity of certain polycyclic aromatic hydrocarbons (PAHs) to aquatic organisms can be greatly increased upon exposure of the organisms to ultraviolet (UV) radiation present in sunlight. The phenomenon of photoactivation of PAHs had received some attention in the laboratory; however, evaluation of the photoinduced toxicity of PAHs in field settings has been limited. In these studies, in situ chambers

  1. Additive Toxicity of Binary Mixtures of Phototoxic Polycyclic Aromatic Hydrocarbons to the Oligochaete Lumbriculus variegatus

    Microsoft Academic Search

    Russell J. Erickson; Gerald T. Ankley; David L. DeFoe; Patricia A. Kosian; Elizabeth A. Makynen

    1999-01-01

    Toxicity of some polycyclic aromatic hydrocarbons (PAHs) can increase by an order of magnitude, or more, in the presence of solar ultraviolet (UV) radiation. In the environment, PAHs exist as complex mixtures, which generally would include multiple PAHs that could cause photoinduced toxicity. Hence, to accurately predict the potential ecological risk of phototoxic PAHs, it is critical to understand their

  2. Examination of Apollo 17 surface fines for porphyrins and aromatic hydrocarbons

    NASA Technical Reports Server (NTRS)

    Rho, J. H.

    1974-01-01

    An Apollo 17 surface fines sample 75081,78, collected from Station 5, was extracted and examined fluorometrically. No porphyrins were found with fluorometric methods capable of detecting 2 times 10 to the minus 14th moles/g of Ni-mesoporphyrin IX in the sample. Also aromatic hydrocarbons were undetected.

  3. Adsorption of polycyclic aromatic hydrocarbons (PAHs) by soil particles: influence on biodegradability and biotoxicity

    Microsoft Academic Search

    Walter D. Weissenfels; Hans-Jiirgen Klewer; Joseph Langhoff

    1992-01-01

    Polycyclic aromatic hydrocarbon (PAH) biodegradation was investigated in contaminated soils from two different industrial sites under simulated land treatment conditions. Soil samples from a former impregnation plant (soil A) showed high degradation rates of PAHs by the autochthonous microorganisms, whereas PAHs in material of a closed-down coking plant (soil B) were not degraded even after inoculation with bacteria known to

  4. Bladder cancer incidence and exposure to polycyclic aromatic hydrocarbons among asphalt pavers

    Microsoft Academic Search

    Igor Burstyn; Hans Kromhout; Christoffer Johansen; Sverre Langard; Timo Kauppinen; Judith Shaham; Gilles Ferro; Paolo Boffetta

    2007-01-01

    Objectives: To investigate the association between exposures to polycyclic aromatic hydrocarbons (PAH) that arises during asphalt paving, and risk of bladder cancer.Methods: 7298 men included in the historical cohort were first employed between 1913 and 1999 in companies applying asphalt in Denmark, Norway, Finland and Israel. The minimal duration of employment for inclusion in the cohort was two seasons of

  5. Effects of Polycyclic Aromatic Hydrocarbons in Northern Bobwhite Quail (Colinus virginianus)

    Microsoft Academic Search

    John M. Brausch; Brett R. Blackwell; Blake N. Beall; Cynthia Caudillo; Venkata Kolli; Céline Godard-Codding; Stephen B. Cox; George Cobb; Philip N. Smith

    2010-01-01

    Polycyclic aromatic hydrocarbons (PAH) are ubiquitous contaminants of aquatic and terrestrial ecosystems, and are known to induce biochemical alterations in exposed organisms. Aside from a variety of adverse physiological effects associated with exposure to petroleum products, oils, and oil sludges, little is known about the effects of individual PAH on birds. Acute toxicity of naphthalene, pyrene, and benz[a]anthracene (BAA) was

  6. Biodegradation of polycyclic aromatic hydrocarbons (PAHs) by Cladosporium sphaerospermum isolated from an aged PAH contaminated soil

    Microsoft Academic Search

    Olivier Potin; Etienne Veignie; Catherine Rafin

    2004-01-01

    The ability of a Deuteromycete fungus, Cladosporium sphaerospermum, previously isolated from soil of an aged gas manufacturing plant, to degrade polycyclic aromatic hydrocarbons was investigated. This strain was able to degrade PAHs in non-sterile soils (average 23%), including high molecular weight PAHs, after 4 weeks of incubation. In a microcosm experiment, PAH depletion was clearly correlated to fungal establishment. In

  7. Polycyclic aromatic hydrocarbons in asteroid 2008 TC3: Dispersion of organic compounds inside asteroids

    E-print Network

    Zare, Richard N.

    Polycyclic aromatic hydrocarbons in asteroid 2008 TC3: Dispersion of organic compounds inside asteroids Hassan SABBAH1* , Amy L. MORROW1 , Peter JENNISKENS2 , Muawia H. SHADDAD3 , and Richard N. ZARE1. Among the predominantly polymict ureilite meteorites collected from the impact of asteroid 2008 TC3

  8. Fungal metabolism of polycyclic aromatic hydrocarbons: past, present and future applications in bioremediation

    Microsoft Academic Search

    C E Cerniglia

    1997-01-01

      This article examines the importance of non-ligninolytic and ligninolytic fungi in the bioremediation of polycyclic aromatic\\u000a hydrocarbon contaminated wastes. The research from the initial studies in Dave Gibson’s laboratory to the present are discussed.

  9. EVALUATION OF SAMPLING AND ANALYTICAL METHODS FOR NICOTINE AND POLYNUCLEAR AROMATIC HYDROCARBON IN INDOOR AIR

    EPA Science Inventory

    The objective of the project was to evaluate a potential collection medium, XAD-4 resin, for collecting nicotine and polynuclear aromatic hydrocarbon (PAH) and to determine whether one collection system and one analytical method will allow quantification of both compound classes ...

  10. Sediment fluxes of polycyclic aromatic hydrocarbons in European high altitude mountain lakes

    Microsoft Academic Search

    P. Fernandez; Rosa M. Vilanova; Joan O. Grimalt

    1999-01-01

    Polycyclic aromatic hydrocarbons (PAH) were measured in superficial sediments from several high altitude mountain lakes for assessment of contemporary background PAH pollution levels in Europe. The sediments were obtained by gravity coring, and the upper 0--1 cm were analyzed by gas chromatography coupled to mass spectrometry. The parent PAH mixtures are very uniform irrespective of lake location, lake characteristics, and

  11. Polycyclic aromatic hydrocarbons in fish from remote and high mountain lakes in Europe and Greenland

    Microsoft Academic Search

    I Vives; J. O Grimalt; P Fernández; B Rosseland

    2004-01-01

    Polycyclic aromatic hydrocarbons (PAHs) were analysed in liver of fifty-seven individual trout distributed among seven high mountain lakes in Europe and one remote lake in Greenland. In all cases, very similar distributions were observed in which phenanthrene largely predominated and fluoranthene and pyrene were the second major compounds. These distributions were similar to those observed in the dissolved fraction of

  12. Polycyclic aromatic hydrocarbon composition in soils and sediments of high altitude lakes

    Microsoft Academic Search

    Joan O Grimalt; Barend L van Drooge; Alejandra Ribes; Pilar Fernández; Peter Appleby

    2004-01-01

    Polycyclic aromatic hydrocarbons (PAH) in lake sediments and nearby soils of two European high mountain regions, Pyrenees and Tatra, have been studied. Similar mixtures of parent PAH were observed in all cases, indicating predominance of airborne transported combustion products. Nevertheless, the composition of these atmospherically long-range transported PAH was better preserved in the superficial layers of soils than sediments. This

  13. Phototoxicity of individual polycyclic aromatic hydrocarbons and petroleum to marine invertebrate larvae and juveniles

    Microsoft Academic Search

    Marguerite C. Pelletier; Robert M. Burgess; Kay T. Ho; Anne Kuhn; Richard A. McKinney; Stephan A. Ryba

    1997-01-01

    Phototoxicity resulting from photoactivated polycyclic aromatic hydrocarbons (PAHs) has been reported in the literature for a variety of freshwater organisms. The magnitude of increase in PAH toxicity often exceeds a factor of 100. In the marine environment phototoxicity to marine organisms has not been reported for individual or complex mixtures of PAHs. In this study, larvae and juveniles of the

  14. Source diagnostics of polycyclic aromatic hydrocarbons in urban road runoff, dust, rain and canopy throughfall

    Microsoft Academic Search

    Wei Zhang; Shucai Zhang; Chao Wan; Dapan Yue; Youbin Ye; Xuejun Wang

    2008-01-01

    Diagnostic ratios and multivariate analysis were utilized to apportion polycyclic aromatic hydrocarbon (PAH) sources for road runoff, road dust, rain and canopy throughfall based on samples collected in an urban area of Beijing, China. Three sampling sites representing vehicle lane, bicycle lane and branch road were selected. For road runoff and road dust, vehicular emission and coal combustion were identified

  15. Sampling and Analytical Method Development and Hand Wipe Measurements of Dermal Exposures to Polycyclic Aromatic Hydrocarbons

    Microsoft Academic Search

    Mark Boeniger; Charles Neumeister; Angela Booth-Jones

    2008-01-01

    This article describes the laboratory assessment of a hand and surface wipe sampling method for polycyclic aromatic hydrocarbons (PAHs). The analytical method employed extraction of the wipe samples into dimethyl sulfoxide (DMSO) and high-performance liquid chromatography (HPLC) flourometric detection of pyrene, a predominant PAH in used gasoline engine oils (UGEO). Recovery of pyrene was evaluated for two different sampling media

  16. Particle in a Disk: A Spectroscopic and Computational Laboratory Exercise Studying the Polycyclic Aromatic Hydrocarbon Corannulene

    ERIC Educational Resources Information Center

    Frey, E. Ramsey; Sygula, Andrzej; Hammer, Nathan I.

    2014-01-01

    This laboratory exercise introduces undergraduate chemistry majors to the spectroscopic and theoretical study of the polycyclic aromatic hydrocarbon (PAH), corannulene. Students explore the spectroscopic properties of corannulene using UV-vis and Raman vibrational spectroscopies. They compare their experimental results to simulated vibrational…

  17. Trace Metals and Polycyclic Aromatic Hydrocarbons in an Urbanized Area of Florida

    Microsoft Academic Search

    Maninder K. Chahal; Gurpal S. Toor; Pam Brown

    2010-01-01

    Contamination of soils by a variety of pollutants in urbanized and rapidly urbanizing regions is an ongoing problem in the world. Our objective in this study was to determine the contamination levels of trace metals and polycyclic aromatic hydrocarbons (PAHs) in urban residential soils. Surface (0–15 cm) samples of soils were collected and analyzed from an urbanized region of Florida

  18. APPLICATION OF EPA METHOD 610 TO THE ANALYSIS OF POLYNUCLEAR AROMATIC HYDROCARBONS IN LEACHATE SAMPLES

    EPA Science Inventory

    This report summarizes the results of a spiking study performed on a sanitary landfill leachate matrix. Fifteen polynuclear aromatic hydrocarbons (PNAs) were dosed into the landfill leachate and analyzed using EPA Method 610. The results show that the PNAs containing two, three, ...

  19. Polycyclic aromatic hydrocarbon exposures of children in low-income families1

    Microsoft Academic Search

    JANE C CHUANG; PATRICK J CALLAHAN; CHRISTOPHER W LYU; NANCY K WILSON

    1999-01-01

    Children in low-income families may have high exposures to polycyclic aromatic hydrocarbons (PAH). Such exposures could result from household proximity to heavy traffic or industrial sources, environmental tobacco smoke, contaminated house dust or soil, among others. The objectives of this study were: to establish methods for measuring total PAH exposure of children in low-income families, to estimate the PAH exposures

  20. QSARS FOR PHOTOINDUCED TOXICITY: I. ACUTE LETHALITY OF POLYCYCLIC AROMATIC HYDROCARBONS TO DAPHNIA MAGNA

    EPA Science Inventory

    Research with a variety of aquatic species has shown that while polycyclic aromatic hydrocarbons (PAHs) are generally not acutely toxic in conventional laboratory tests, many are extremely toxic in the presence of sunlight. n an effort to develop a model for predicting which PAHs...

  1. CONCENTRATIONS AND PHASE DISTRIBUTIONS OF NITRATED AND OXYGENATED POLYCYCLIC AROMATIC HYDROCARBONS IN AMBIENT AIR

    EPA Science Inventory

    The concentrations of nitrated and oxygenated aromatic hydrocarbons (PAH) in ambient air, both in the vapor phase and adsorbed on airborne particles, were measured over a 12-month period in Houston, Texas. easonal variations in the levels of the target compounds were weakly relat...

  2. Trace elements and polycyclic aromatic hydrocarbons (PAHs) concentrations in deep Gulf of Mexico sediments

    Microsoft Academic Search

    Terry L. Wade; Yousra Soliman; Stephen T. Sweet; Gary A. Wolff; Bobby J. Presley

    2008-01-01

    The concentrations of polycyclic aromatic hydrocarbons (PAHs) and trace elements were determined for surface (top 2cm) sediment samples collected during the deep Gulf of Mexico benthos (DGoMB) study .These elements and compounds are known to be toxic to organisms at high concentrations and may affect biological communities. There is no indication of major anthropogenic input of the elements Be, Co,

  3. REDUCTIVE TRANSFORMATIONS OF HALOGENATED AROMATIC HYDROCARBONS IN ANAEROBIC SEDIMENT-WATER SYSTEMS: KINETICS, MECHANISMS, AND PRODUCTS

    EPA Science Inventory

    The degradation of several classes of halogenated aromatic hydrocarbons in methanogenic sediment-water systems was examined in laboratory studies. everal transformation processes were shown to occur, leading to formation of a variety of products. n the study, a clear distinction ...

  4. Urban runoff as a source of polycyclic aromatic hydrocarbons to coastal waters

    Microsoft Academic Search

    Eva J. Hoffman; Gary L. Mills; James S. Latimer; James G. Quinn

    1984-01-01

    Urban runoff samples collected from four storm drains, each serving a different land use, were analyzed for selected polycyclic aromatic hydrocarbons (PAHs) by gas chromatography. The PAH concentrations varied widely during the history of each storm and appeared to be most concentrated in first or second flushes. Higher molecular weight PAHs were mostly found associated with the particulates and were

  5. Physiological effects of polycyclic aromatic hydrocarbons on soft-shell clam Mya arenaria

    Microsoft Academic Search

    H. Frouin; J. Pellerin; M. Fournier; E. Pelletier; P. Richard; N. Pichaud; C. Rouleau; F. Garnerot

    2007-01-01

    The aim of this study was to investigate the effects of polycyclic aromatic hydrocarbons (PAHs) on the physiological status of the bivalve Mya arenaria. Specimens were exposed to four different sources of PAHs: aluminium smelter soot, sediment from an industrial discharge pound, charcoal fine particles and dietary PAHs assessed by feeding clams with phytoplankton freshly impregnated with dissolved PAHs. The

  6. THE EFFECT OF IRRADIANCE SPECTRA ON THE PHOTOACTIVATED TOXICITY OF THREE POLYCYCLIC AROMATIC HYDROCARBONS

    EPA Science Inventory

    Photoinduced toxicity of polycyclic aromatic hydrocarbons (PAHs) is dependent on the concentration of compounds present and the dose of light recieved. Of the light present, only those wavelengths absorbed by the compound have the potential to initiate the photochemical events un...

  7. COMPARATIVE STUDIES OF THE EFFECT OF POLYCYCLIC AROMATIC HYDROCARBON GEOMETRY ON THE HYDROLYSIS OF DIOL EPOXIDES

    EPA Science Inventory

    Comparative studies of the effect of polycyclic aromatic hydrocarbon geometry on the hydrolysis of diol epoxides The interaction of the diol epoxides (DEs) of both planar and non-planar PAHs with water have been examined using quantum mechanical and molecular dynamics. Th...

  8. SAR Models for Estimating the Percutaneous Absorption of Polynuclear Aromatic Hydrocarbons

    Microsoft Academic Search

    T. A. Roy; A. J. Krueger; C. R. Mackerer; W. Neil; A. M. Arroyo; J. J. Yang

    1998-01-01

    A structure-activity relationship (SAR) of the in vitro percutaneous absorption of polycyclic aromatic hydrocarbons (PAH) is described. The data set consisted of 60 three to seven ring PAH. Over 50 numeric descriptors were generated from the modeled molecular structures. Computer aided methods were used to evaluate descriptors and develop linear expressions relating the percent of dermally applied PAH dose absorbed

  9. Effect of three aromatic hydrocarbons on respiration and heart rates of the mussel, mytilus californianus

    SciTech Connect

    Sabourin, T.D.; Tullis, R.E.

    1981-06-01

    The effects of petroleum derivatives on morality of marine invertebrates is now well established. Aromatics are considered to be the most toxic of all oil fractions. Recent studies of marine invertebrates have focused mainly upon respiration, locomotion, and growth. The filter feeding marine bivalves have received primary attention due to their proximity to coastal oil spills, importance in human food consumption and possible role in petroleum hydrocarbon bioconcentration. If these organisms are to be used as monitors in the future, then it is important to learn something of how quickly the bivalve responds metabolically to changes in ambient levels of petroleum hydrocarbons. Respiration and heart activity reveal a great deal of information concerning the physiological state of the bivalve. We report measrements of these two variables in the mussel, Mytilus californianus (Conrad), under conditions of exposure to, and recovery from, three aromatic hydrocarbons.

  10. Infrared Signature of the Cation-? Interaction between Calcite and Aromatic Hydrocarbons.

    PubMed

    Wang, Haitao; Grant, Daniel J; Burns, Peter C; Na, Chongzheng

    2015-06-01

    The cation-? interaction is proposed as an important mechanism for the adsorption of aromatic hydrocarbons having non-zero quadrupole moments by mineral surfaces. Direct evidence supporting such a mechanism is, however, limited. Using the model mineral calcite, we probe the cation-? interaction with adsorbed benzene, toluene, and ethylbenzene (BTE) molecules using attenuated total reflectance Fourier transform infrared spectroscopy. We show that the presence of calcite increases the energy required to excite the synchronized bending of aromatic C-H bonds of BTE molecules. The unique conformation of this vibrational mode indicates that the planar aromatic rings of BTE molecules are constrained in a tilted face-down position by the cation-? interaction, as further confirmed by density functional theory calculations. Our results suggest that the shift of the excitation energy of the aromatic C-H bending may be used as an infrared signature for the cation-? interaction occurring on mineral surfaces. PMID:25974679

  11. Joint thermal hydrogenation conversions of aromatic and nonaromatic hydrocarbons

    Microsoft Academic Search

    R. R. Akhundova; Yu. G. Kambarov; Kh. G. Isaev; R. M. Aliev; N. N. Nadzhafov

    2009-01-01

    During the last few decades, processes for the high-temperature hydrogenation of liquid products from pyrolysis operations have been used extensively in benzene production. In certain published reports, it has been noted that reactions of nonaromatic hydrocarbon hydrocracking have an initiating effect on reactions of alkylbenzene dehydroalkylation. However, no additional detailed information is available on the relationships in such a complex

  12. Solidphase extraction of polycyclic aromatic hydrocarbons from soil samples

    Microsoft Academic Search

    P. R. Kootstra; M. H. C. Straub; G. H. Stil; E. G. van der Velde; W. Hesselink; C. C. J. Land

    1995-01-01

    A new solid-phase extraction (SPE) method was developed for the analysis of 16 polyaromatic hydrocarbons (PAHs) on the US Environmental Protection Agency priority list, in soil samples. Different types of SPE columns were tested and conditioning and elution steps were optimised. In the final procedure, soil samples are extracted with acetone and, after dilution with HPLC-grade water, loaded on a

  13. Neurobehavioral effects of acute exposure to aromatic hydrocarbons.

    PubMed

    McKee, Richard H; Lammers, J H C M; Muijser, H; Owen, D E; Kulig, B M

    2010-01-01

    This article reports the results of neurobehavioral tests on representative aromatic constituents, specifically C(9) to C(11) species. The testing evaluated effects in several domains including clinical effects, motor activity, functional observations, and visual discrimination performance. Exposures ranging from 600 to 5000 mg/m(3), depending on the molecular weights of the specific aromatic constituents, produced minor, reversible effects on the central nervous system (CNS), particularly in the domains of gait and visual discrimination. There was little evidence of effects at lower exposure levels. There was some evidence of respiratory effects at 5000 mg/m(3) in 1 study, and there were also minor changes in body weight and temperature. The CNS effects became less pronounced with repeated exposures, corresponding to lower concentrations in the brain of 1 representative substance, 1,2,4-trimethyl benzene (TMB). At high exposure levels, the alkyl benzenes apparently induced their own metabolism, increasing elimination rates. PMID:20448260

  14. Corona discharge ion mobility spectrometry of aliphatic and aromatic hydrocarbons

    Microsoft Academic Search

    Helko Borsdorf; Hubert Schelhorn; Johannes Flachowsky; Hans-Rüdiger Döring; Joachim Stach

    2000-01-01

    Positive ion mobility spectra of n-alkanes (n-C5 to n-C19), branched chain alkanes (C5 to C9) and aromatic compounds (benzene and alkylated benzenes) were acquired with an ion mobility spectrometer equipped with a corona discharge ionization source. Reduced mobilities and mass-to-mobility correlation curves were determined for these compounds. Depending on their concentration, the n-alkanes form one or two product ion peaks.

  15. Polycyclic Aromatic Hydrocarbons in Rock Oysters: A Baseline Study

    Microsoft Academic Search

    R. Kagi; R. Alexander; M. Cumbers

    1985-01-01

    Coral-rock oysters were collected in September 1982 from six locations in the area of Mermaid Sound in North-Western Australia. Analysis was carried out by digestion of the samples, followed by solvent extraction and analysis of the extracts using HPLCUVF and GC-MS.The levels of two- and three-ring aromatics ranged from very low for the site outside Mermaid Sound and for one

  16. Attenuation of dilute aromatic hydrocarbon transport by a block copolymer in a compacted vertisol 

    E-print Network

    Akin, James Browning

    2001-01-01

    fixed wall permeameters. The compacted Ships clay met the United States Environmental Protection Agency's mandated saturated hydraulic conductivity of 10?? cm sec?¹ at polymer contents of 3% (wt) polymer or less. The presence of dissolved aromatic...

  17. Determination of aromatic hydrocarbons in asphalt release agents using headspace solid-phase microextraction and gas chromatography-mass spectrometry.

    PubMed

    Tang, Bing; Isacsson, Ulf

    2005-04-01

    The possibility of quantitative analysis of aromatic hydrocarbons in oil-based asphalt release agents was investigated using headspace solid-phase microextraction (HS-SPME) followed by gas chromatography-mass spectrometry (GC-MS). The target analytes studied were benzene, toluene, ethylbenzene, p-, m-, and o-xylene (BTEX) and 1,3,5-trimethylbenzene and 1,2,4-trimethylbenzene. Experimental parameters influencing HS-SPME efficiency were studied (equilibration time between sample and headspace and between headspace and SPME fiber, sample amount and sample matrice effects). A HS-SPME method using hexadecane as a surrogate matrice was developed. The detection limit was estimated as 0.03-0.08 ppm (w/w) for the target analytes investigated. Good linearity was observed (R2 > 0.999) for all calibration curves at high, medium and low concentration level. The repeatability of the method (RSD, relative standard deviation) was found to be less than 10% (generally less than 5%) in triplicate samples and approximately 2% at eight consecutive tests on one and the same sample. The accuracy of the method given by recovery of spiked samples was between 85 and 106% (generally between 95 and 105%). The HS-SPME method developed was applied to four commercially available asphalt release agents. External calibration and standard addition approaches were investigated regarding accuracy. The results showed that standard addition generates higher accuracy than external calibration. The contents of target aromatic hydrocarbons in the asphalt release agents studied varied greatly from approximately 0.1-700 ppm. The method described looks promising, and could be a valuable tool for determination of aromatic hydrocarbons in different types of organic matrices. PMID:15830950

  18. A novel method for evaluating bioavailability of polycyclic aromatic hydrocarbons in sediments of an urban stream.

    PubMed

    Nakajima, F; Baun, A; Ledin, A; Mikkelsen, P S

    2005-01-01

    Hydrophobic organic pollutants in urban wet weather discharges can accumulate in the sediments of receiving waters and may have adverse effects on the ecological system, especially on benthic organisms. Here, a novel method is developed for evaluating the bioavailability of such hydrophobic organic pollutants by considering the digestive guts in deposit-feeding polychaetes. We compared the amount of polycyclic aromatic hydrocarbons (PAHs) extracted by an organic solvent and by sodium dodecyl sulfate (SDS) solution (as a hypothetical digestive gut fluid of polychaetes) and interpreted the ratio of the two values as bioavailability. The sediment extracts were applied to bacterial acute toxicity tests and algal growth inhibition tests. Sediment samples were collected from an urban stream system receiving wet weather discharges. The bioavailability of the total amount of 12 PAHs in the sediments was in the range 14-38% based on the results from the GC/MS determination of the two different extracts. Lower molecular PAHs showed higher bioavailability compared to the higher molecular ones. The sediment extracts were shown to be toxic towards both algae and bacteria. The SDS extracts showed similar or higher toxicity in the two biotests compared to the organic solvent extracts in spite of their lower PAHs content. PMID:15850200

  19. Determination of polycyclic aromatic hydrocarbons in marine samples by high-performance liquid chromatography

    SciTech Connect

    Obana, H.; Hori, S.; Kashimoto, T.

    1981-05-01

    It has been reported that polycyclic aromatic hydrocarbons (PAHs) are widely distributed in the environment, although their concentrations are quite low. Some PAHs, benzo(a)pyrene, dibenz(a,h)anthracene and 3-methycholanthrene, are carcinogenic to mammals after in vivo hydroxylation by mixed function oxidases. PAHs originate largely from smoke, soot, and exhaust gas produced by combustion and from petroleum oil spilled into the sea, so that the quantity of PAHs in the environment is broadly related to the level of contamination in a given region. Although PAHs have been determined by a TLC-fluorescence method, these methods suffer from complex pretreatment. On the other hand, the development of high-performance liquid chromatography (HPLC) has made it possible to analyze PAHs with good separation and high sensitivity and to simplify the pretreatment processes. In this study, ten PAHs in sediments, oyster, and wakame seaweed were determined by HPLC with a fluorescence detector (HPLC-FD). The contents and the patterns of PAHs found in sediments and marine samples may be used as an indicator of petroleum contamination in the sea.

  20. Occurrence of polycyclic aromatic hydrocarbons (PAHs) in seawater from the Western Taiwan Strait, China.

    PubMed

    Wu, Yu-Ling; Wang, Xin-Hong; Li, Yong-Yu; Hong, Hua-Sheng

    2011-01-01

    Seawater samples (including surface water and bottom water) were collected from the Western Taiwan Strait (WTS) during June 24-25, 2009; polycyclic aromatic hydrocarbons (PAHs) in dissolved phase and particulate phase were analyzed, respectively. The results showed that the total concentrations of PAHs in the dissolved phase and particulate phase were ranged from 12.3 to 58.0 ng L(-1), and 10.3-45.5 ng L(-1), which showed a low-middle contamination level in the China Seas. The spatial variability of PAHs may be related to the complicated currents of WTS, especially the Min-Zhe coastal current. PAHs diagnostic ratios suggested that PAHs mainly originated from the inputs of pyrolytic (combustion) sources, which might be contributed to land-based atmospheric deposition. The particle-water partition coefficients of individual PAH showed that partitions were not correlated with suspended particulate matter content, dissolved organic carbon or salinity, similar to the Yangtze coastal area. PMID:21440914

  1. Distribution of polycyclic aromatic hydrocarbons in sediments of Akaki River, Lake Awassa, and Lake Ziway, Ethiopia.

    PubMed

    Mekonnen, Kebede Nigussie; Chandravanshi, Bhagwan Singh; Redi-Abshiro, Mesfin; Ambushe, Abayneh Ataro; McCrindle, Robert Ian; Moyo, Stanley

    2015-07-01

    The quantification of 14 polycyclic aromatic hydrocarbons (PAHs) was carried out in sediment samples collected from Akaki River, Lake Awassa, and Lake Ziway, Ethiopia. The concentration of PAHs in the samples was determined using gas chromatography-mass spectrometry (GC-MS) in selected ion monitoring (SIM) mode, after microwave-assisted extraction (MAE), using acetone/n-hexane (1:1, v/v) mixture. The accuracy of the method was determined by extracting and analyzing New York/New Jersey waterway sediment standard reference material (SRM 1944). The measured concentrations of PAHs in SRM 1944 agreed well with the certified values. In samples from Akaki River, Lake Awassa, and Lake Ziway, the total content of PAHs determined ranged from 0 to 3070 ng/g (average 534 ng/g), 24.9 to 413 ng/g (average 169 ng/g), and 15.0 to 305 ng/g (average 175 ng/g), respectively. Source ratios indicated that the PAHs were mainly from petrogenic origin. Sediments from all sampling sites indicated negligible levels of toxicity with no risk of adverse biological effects. PMID:26122125

  2. Polycyclic aromatic hydrocarbons and their oxygenated derivatives in the urban atmosphere of Athens.

    PubMed

    Andreou, G; Rapsomanikis, S

    2009-12-15

    Ambient samples of coarse and fine organic particulate matter collected from two urban sites in the city of Athens over one warm and one cold period have been solvent-extracted and quantitatively characterized by gas chromatography-mass spectrometry for their content of polycyclic aromatic hydrocarbons (PAHs) and oxidized PAHs (oxyPAHs). Variable concentrations were observed for the two distinct monthly periods representing a cold, dry period and a summer period, relating to strong local primary emissions and to lower emissions with more stable meteorological conditions, respectively. Additionally, gaseous concentrations of selected PAHs were calculated, revealing that the relative proportions between gaseous and particle phase of individual compounds may differ significantly between summer and late winter, reflecting changes in PAH emission sources and climate conditions. In fact almost all of SigmaPAHs were attributed to combustion sources (82-92%), while more than half are considered as comprising of probable human carcinogens (47-62%). Traffic was confirmed as the major contributor of PAHs when appropriate diagnostic ratios and traffic marker compounds were used. This approach also led to the estimation of diesel versus petrol contribution to the atmospheric PAH burden, using the methylphenanthrene to phenanthrene ratio. The fourteen oxygenated polycyclic compounds that were quantified had greater concentrations in the colder period. Among these compounds 9,10-phenanthrenequinone, 1-pyrenecarboxaldehyde and 9H-fluoren-9-one had the highest concentrations. PMID:19647935

  3. Optimization of purification processes to remove polycyclic aromatic hydrocarbons (PAHs) in polluted raw fish oils.

    PubMed

    Yebra-Pimentel, Iria; Fernández-González, Ricardo; Martínez-Carballo, Elena; Simal-Gándara, Jesús

    2014-02-01

    Fish oils are one of the main sources of health promoting nutrients such as n-3 fatty acids in animal and human diet. Nevertheless, they could be an important source of persistent organic pollutants (POPs). Different strategies of decontamination processes to reduce polycyclic aromatic hydrocarbon (PAH) levels in fish oils, such as solvent extraction (ethanol) and adsorbent extraction using commercially available (activated carbon) and sustainable adsorbents (mussel shell and wood ashes), were compared. Adsorption conditions were evaluated and optimized by an experimental design and the experimental results were adjusted to response surfaces. In this way, PAH removals increased with increasing of individual PAH molecular weight and they range from 80% to 100% using activated carbon and from 10% to 100% using wood ashes. Pine wood ashes showed similar removal rates to activated carbon (87%-100%) excluding F (51%) and P (42%). No PAH removal was observed using mussel shell ashes. Ethanol extraction was also optimized and showed a good performance in the extraction of PAHs. However, it does affect their ?-3 fatty acid contents. Finally, real oil samples from different fishing areas: Spain, South America, and North Europe were selected for the decontamination experiments under experimental conditions previously optimized. PMID:24231673

  4. Bioavailability and biotransformation of polycyclic aromatic hydrocarbons in the benthos of coastal Massachusetts

    SciTech Connect

    McElroy, A.E. [State Univ. of New York, Stony Brook, NY (United States); MacGillivray, A.R. [Weston Inc., Lionville, PA (United States); Shiaris, M.P. [Univ. of Massachusetts, Boston, MA (United States); Sisson, J.D. [Woods Hole Oceanographic Institution, MA (United States)

    1994-12-31

    To better understand the environmental factors controlling PAH fate in coastal sediments and to obtain more realistic estimates of biodegradation rates and removal of polycyclic aromatic hydrocarbons (PAHs) from coastal systems, the authors examined the effect of sediment organic matter concentration and previous contaminant loadings on bioavailability, biotransformation, and biodegradation of two model PAHs: phenanthrene (PHN) and benzanthracene (BA) in benthic microcosms. These processes were assessed in the presence and absence of two representative infaunal organisms, the deposit feeding polychaete Scolecolepides viridis and the suspension feeding bivalve Mya arenaria. Organic carbon content of the sediment does not appear to be the primary controlling factor for PAH accumulation or metabolism by macrofauna or metabolism and degradation by microbes. Susceptibility of an individual PAH to prokaryotic degradation differs from its susceptibility to metabolism by eukaryotes. S. viridis, accumulated more PHN and Ba than M.arenaria. In addition, worms rapidly metabolized PAH, with polar metabolites accounting for more than 50% of the total body burdens of PAH measured. Most, and in some cases almost all, material removed from the sediment reservoir had been transformed into polar metabolites or completely mineralized to CO{sub 2}. Efforts should be made to include metabolism in fate and transport models of PAH in nearshore benthic environments.

  5. Detection of polycyclic aromatic hydrocarbons in different types of processed foods.

    PubMed

    Kumosani, Taha A; Moselhy, Said S; Asseri, Abdullah M; Asseri, Amer Hamzah

    2013-04-01

    Polycyclic aromatic hydrocarbons (PCAHs), particularly those with a high molecular weight, have been classified as probable carcinogens to humans. The aim of the present study is to determine the levels of PCAHs in samples of meat, fish, chicken, fried potato, and toasted bread, which will be thermally processed using conventional and microwave ovens. Different samples will be collected and analyzed for five PCAHs including pyrene, benzo(a)anthracene, benzo(e)pyrene, benzoflouroanthene, and benzo(a)pyrene. The analytical method involves saponification with methanolic potassium hydroxide, extraction with cyclohexane, and determination by high-performance liquid chromatography. The obtained results showed that there is a variation in the detected PCAHs in different foodstuffs. Fried potato processed by conventional oven or microwave oven showed none of the selected studied PCAHs. It was found that, chicken showed higher content levels of total PCAHs than the meat and fish. Data are the highest mean concentrations of fluoranthene and benzo(a)pyrene but within low limit. The obtained results were compared with international permissible levels to avoid pollution, which may cause hazardous effects on individual and society. PMID:22294443

  6. [Distribution and source apportionment of polycyclic aromatic hydrocarbons (PAHs) in urban rainfall runoff].

    PubMed

    Wu, Zi-Lan; Yang, Yi; Liu, Min; Lu, Min; Yu, Ying-Peng; Wang, Qing; Zheng, Xin

    2014-11-01

    Runoff samples were collected from traffic roads, campus, residential road and roof in a typical rain event. Polycyclic aromatic hydrocarbons (PAHs) in both dissolved and particle phases were investigated at impervious surfaces. The PAHs wash-off process at different monitoring sites was analyzed. The scatters of first flush were conducted in a method of fitting power function to quantitatively assess the magnitude of first flush effect (FFE). The sources of PAHs were identified using factor analysis. The results showed that PAHs concentrations in runoff samples varied from 317.21 ng x L(-1) to 10364.3 ng x L(-1) with the maximal and minimal contents of PAHs found on Longwu Road and campus, respectively. The values of event mean concentration ( EMC) varied considerably at different sampling sites. The concentration of washed-off pollutant generally decreased with runoff duration, which showed an obvious attenuation trend. The runoff process indicated the occurrence of FFE at different levels. PAHs mainly came from the incomplete combustion of fossil fuels, oil leakage and coking, and the contribution of each source was different in accordance with various surfaces. PMID:25639088

  7. Fugacity approach to evaluate the sediment-water diffusion of polycyclic aromatic hydrocarbons.

    PubMed

    Wang, De-Gao; Alaee, Mehran; Byer, Jonathan; Liu, Yong-Jun; Tian, Chong-Guo

    2011-06-01

    Diffusion is an important process for sediment-water exchange and plays a vital role in controlling water quality. Fugacity fraction (ff) was used to estimate the sediment-water diffusion of polycyclic aromatic hydrocarbons (PAHs) between seawater and surficial sediment. A total of 33 surface sediment and sea water samples were collected concurrently from the northeast coastal area in China and 25 PAHs were analyzed including the alkylated and chlorated PAHs. Fugacity fraction was calculated based on the PAH concentrations in water and sediment, octanol-water partition coefficient of PAHs, organic matter content in sediment, and density of sediment. The calculated results showed that ff increased with decreasing molecular weight of PAHs. The low molecular weight PAHs (2-3 rings) transferred from sediment to water and the sediment acted as a secondary source to the water. The medium molecular weight PAHs (4-5 rings) were close to the sediment-water equilibrium and the transfer tendency shifted between sediment and water. The high molecular weight PAHs (5-6 rings) transferred from water into sediment and the sediment acted as a sink. Soot carbon and the difference of PAH concentrations between sediment and water were found to be important factors affecting the sediment-water diffusion. This study provided new insight into the process of sediment-water diffusion, which has a great influence on the quality of water, especially in severely-polluted sediment areas. PMID:21552633

  8. Sediment-porewater partition of polycyclic aromatic hydrocarbons (PAHs) from Lanzhou Reach of Yellow River, China.

    PubMed

    Yu, Yong; Xu, Jian; Wang, Ping; Sun, Hongwen; Dai, Shugui

    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(2)=0.756). Concentrations of total PAHs in porewaters ranged from 48.2 to 206 microg/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 microg/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(oc)(') of the PAHs between sediments and porewaters were significantly correlated with their octanol-water partition coefficients (logK(ow)) when logK(ow) values were less than 5.5 (naphthalene (Nap) excluded). logK(oc)(') 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. PMID:19059717

  9. Atmospheric chemistry of gas-phase polycyclic aromatic hydrocarbons: formation of atmospheric mutagens.

    PubMed Central

    Atkinson, R; Arey, J

    1994-01-01

    The atmospheric chemistry of the 2- to 4-ring polycyclic aromatic hydrocarbons (PAH), which exist mainly in the gas phase in the atmosphere, is discussed. The dominant loss process for the gas-phase PAH is by reaction with the hydroxyl radical, resulting in calculated lifetimes in the atmosphere of generally less than one day. The hydroxyl (OH) radical-initiated reactions and nitrate (NO3) radical-initiated reactions often lead to the formation of mutagenic nitro-PAH and other nitropolycyclic aromatic compounds, including nitrodibenzopyranones. These atmospheric reactions have a significant effect on ambient mutagenic activity, indicating that health risk assessments of combustion emissions should include atmospheric transformation products. PMID:7821285

  10. Polycyclic aromatic hydrocarbon degradation of phytoplankton-associated Arenibacter spp. and description of Arenibacter algicola sp. nov., an aromatic hydrocarbon-degrading bacterium.

    PubMed

    Gutierrez, Tony; Rhodes, Glenn; Mishamandani, Sara; Berry, David; Whitman, William B; Nichols, Peter D; Semple, Kirk T; Aitken, Michael D

    2014-01-01

    Pyrosequencing of the bacterial community associated with a cosmopolitan marine diatom during enrichment with crude oil revealed several Arenibacter phylotypes, of which one (OTU-202) had become significantly enriched by the oil. Since members of the genus Arenibacter have not been previously shown to degrade hydrocarbons, we attempted to isolate a representative strain of this genus in order to directly investigate its hydrocarbon-degrading potential. Based on 16S rRNA sequencing, one isolate (designated strain TG409(T)) exhibited >99% sequence identity to three type strains of this genus. On the basis of phenotypic and genotypic characteristics, strain TG409(T) represents a novel species in the genus Arenibacter, for which the name Arenibacter algicola sp. nov. is proposed. We reveal for the first time that polycyclic aromatic hydrocarbon (PAH) degradation is a shared phenotype among members of this genus, indicating that it could be used as a taxonomic marker for this genus. Kinetic data for PAH mineralization rates showed that naphthalene was preferred to phenanthrene, and its mineralization was significantly enhanced in the presence of glass wool (a surrogate for diatom cell surfaces). During enrichment on hydrocarbons, strain TG409(T) emulsified n-tetradecane and crude oil, and cells were found to be preferentially attached to oil droplets, indicating an ability by the strain to express cell surface amphiphilic substances (biosurfactants or bioemulsifiers) as a possible strategy to increase the bioavailability of hydrocarbons. This work adds to our growing knowledge on the diversity of bacterial genera in the ocean contributing to the degradation of oil contaminants and of hydrocarbon-degrading bacteria found living in association with marine eukaryotic phytoplankton. PMID:24212584

  11. Nordic laboratory intercomparison of supercritical fluid extraction for the determination of total petroleum hydrocarbon, polychlorinated biphenyls and polycyclic aromatic hydrocarbons in soil

    Microsoft Academic Search

    Kari Hartonen; Søren Bøwadt; Hans Peter Dybdahl; Kerstin Nylund; Sune Sporring; Hanne Lund; Frøydis Oreld

    2002-01-01

    Two developed supercritical fluid extraction (SFE) methods [one for the determination of total petroleum hydrocarbon (TPH) and polychlorinated biphenyls (PCBs), and one for polycyclic aromatic hydrocarbons (PAHs) and creosote components in soil] were evaluated in a Nordic laboratory intercomparison study with 11 participating laboratories. The interlaboratory comparison showed that excellent recoveries can be obtained with SFE for PAHs and PCBs

  12. Aromatic hydrocarbons associated with brines from geopressured wells

    SciTech Connect

    Keeley, D.F.; Meriwether, J.R.

    1991-01-01

    The measurement of the basic physical chemical properties of the components of brine produced in the US DOE geopressured wells is necessary to provide the fundamental data necessary for understanding the mechanisms by which constituents of petroleum migrate and are partitioned into different phases in various geologic strata. The cryocondensate materials, which we sample, are present in the geopressured brines of all the wells observed to date. These materials are a complex mixture of aromatic compounds ranging in complexity from benzene to highly substituted anthracenes. While data is available for room temperature and for solutions of pure water, there is little earlier information on these compounds in solutions of higher salinity and at elevated temperatures. Our work extended the basic solubility data for benzene and toluene (two of the major aromatic constituents of the geopressured brine) to higher sodium chloride concentrations. The techniques we have developed during the course of this work allows us to make solubility measurements with precision and to make major contributions to the basic literature. It is important to realize that reliable data on these fundamental quantities comes only with great attention to detail and an insistence on consistency and reproducibility. To determine the solubility of one compound at one set of conditions requires the manual injection of a minimum of 45 samples into a gas chromatograph and an analysis of each chromatogram. 10 figs., 10 tabs.

  13. Vertical distribution of polycyclic aromatic hydrocarbons (PAHs) in Hunpu wastewater-irrigated area in northeast China under different land use patterns

    Microsoft Academic Search

    Ru Xiao; Xiaoming Du; Xiaozhen He; Yuejin Zhang; Zhihua Yi; Fasheng Li

    2008-01-01

    The concentrations of polycyclic aromatic hydrocarbons (PAHs) were determined in groundwater and soil profiles from upland\\u000a field and paddy field in the Hunpu wastewater-irrigated area of northeast China. In the study area, the peak concentrations\\u000a of total PAHs were within or just below the topsoil, and the contents decline with depth at various trend verified by the\\u000a Spearman’s rank correlation

  14. Genome Sequence of Porticoccus hydrocarbonoclasticus Strain MCTG13d, an Obligate Polycyclic Aromatic Hydrocarbon-Degrading Bacterium Associated with Marine Eukaryotic Phytoplankton

    PubMed Central

    Whitman, William B.; Huntemann, Marcel; Copeland, Alex; Chen, Amy; Kyrpides, Nikos; Markowitz, Victor; Pillay, Manoj; Ivanova, Natalia; Mikhailova, Natalia; Ovchinnikova, Galina; Andersen, Evan; Pati, Amrita; Stamatis, Dimitrios; Reddy, T. B. K.; Ngan, Chew Yee; Chovatia, Mansi; Daum, Chris; Shapiro, Nicole; Cantor, Michael N.; Woyke, Tanja

    2015-01-01

    Porticoccus hydrocarbonoclasticus strain MCTG13d is a recently discovered bacterium that is associated with marine eukaryotic phytoplankton and that almost exclusively utilizes polycyclic aromatic hydrocarbons (PAHs) as the sole source of carbon and energy. Here, we present the genome sequence of this strain, which is 2,474,654 bp with 2,385 genes and has an average G+C content of 53.1%.

  15. Genome Sequence of Polycyclovorans algicola Strain TG408, an Obligate Polycyclic Aromatic Hydrocarbon-Degrading Bacterium Associated with Marine Eukaryotic Phytoplankton.

    PubMed

    Gutierrez, Tony; Thompson, Haydn F; Angelova, Angelina; Whitman, William B; Huntemann, Marcel; Copeland, Alex; Chen, Amy; Kyrpides, Nikos; Markowitz, Victor; Palaniappan, Krishnaveni; Ivanova, Natalia; Mikhailova, Natalia; Ovchinnikova, Galina; Andersen, Evan; Pati, Amrita; Stamatis, Dimitrios; Reddy, T B K; Ngan, Chew Yee; Chovatia, Mansi; Daum, Chris; Shapiro, Nicole; Cantor, Michael N; Woyke, Tanja

    2015-01-01

    Polycyclovorans algicola strain TG408 is a recently discovered bacterium associated with marine eukaryotic phytoplankton and exhibits the ability to utilize polycyclic aromatic hydrocarbons (PAHs) almost exclusively as sole sources of carbon and energy. Here, we present the genome sequence of this strain, which is 3,653,213 bp, with 3,477 genes and an average G+C content of 63.8%. PMID:25814607

  16. Genome Sequence of Porticoccus hydrocarbonoclasticus Strain MCTG13d, an Obligate Polycyclic Aromatic Hydrocarbon-Degrading Bacterium Associated with Marine Eukaryotic Phytoplankton.

    PubMed

    Gutierrez, Tony; Whitman, William B; Huntemann, Marcel; Copeland, Alex; Chen, Amy; Kyrpides, Nikos; Markowitz, Victor; Pillay, Manoj; Ivanova, Natalia; Mikhailova, Natalia; Ovchinnikova, Galina; Andersen, Evan; Pati, Amrita; Stamatis, Dimitrios; Reddy, T B K; Ngan, Chew Yee; Chovatia, Mansi; Daum, Chris; Shapiro, Nicole; Cantor, Michael N; Woyke, Tanja

    2015-01-01

    Porticoccus hydrocarbonoclasticus strain MCTG13d is a recently discovered bacterium that is associated with marine eukaryotic phytoplankton and that almost exclusively utilizes polycyclic aromatic hydrocarbons (PAHs) as the sole source of carbon and energy. Here, we present the genome sequence of this strain, which is 2,474,654 bp with 2,385 genes and has an average G+C content of 53.1%. PMID:26089431

  17. Effect of dissolved aromatic hydrocarbons on the growth of marine bacteria in batch culture.

    PubMed Central

    Calder, J A; Lader, J H

    1976-01-01

    Dissolved aromatic hydrocarbons were found to decrease growth rate and maximum cell density of marine bacteria in batch cultures. The magnitude of the decrement was observed to be a function of concentration of the hydrocarbon and inherent toxicity. The inherent toxicity was observed to increase inversely with solubility such that naphthalene at 100 muM concentration demonstrated a toxic effect similar to benzopyrene at 0.02 muM. A partial oxidation product of naphthalene was found to be more effective in decreasing growth parameters than naphthalene at equivalent concentrations and to cause complete cessation of growth at the higher concentrations permitted by its polar structure. PMID:970939

  18. Effectiveness of in site biodegradation for the remediation of polycyclic aromatic hydrocarbons at a contaminated oil refinery, Port Arthur, Texas 

    E-print Network

    Moffit, Alfred Edward

    2000-01-01

    The effectiveness of bioremediation for the removal of polycyclic aromatic hydrocarbons (PAHs) from sediments contaminated with highly weathered petroleum was evaluated at a contaminated oil refinery. The sediments were chronically contaminated...

  19. TRENDS OF POLYCYCLIC AROMATIC HYDROCARBON LEVELS AND MUTAGENICITY IN SANTIAGO'S INHALABLE AIRBORNE PARTICLES IN THE PERIOD 1992-1996.

    EPA Science Inventory

    Abstract Trends of polycyclic aromatic hydrocarbons (PAHs) for 1992-1996 (cold season) and their mutagenic activity were investigated in organic extracts from the Santiago. Chile. inhalable particles (PM10). The highest PAH concentrations were observed in 1992 and decline...

  20. FORMATION OF POLYCYCLIC AROMATIC HYDROCARBONS AND THEIR GROWTH TO SOOT -A REVIEW OF CHEMICAL REACTION PATHWAYS. (R824970)

    EPA Science Inventory

    The generation by combustion processes of airborne species of current health concern such as polycyclic aromatic hydrocarbons (PAH) and soot particles necessitates a detailed understanding of chemical reaction pathways responsible for their formation. The present review discus...

  1. The Optical Spectrum of a Large Isolated Polycyclic Aromatic Hydrocarbon: Hexa-peri-hexabenzocoronene, C42H18

    NASA Astrophysics Data System (ADS)

    Kokkin, Damian L.; Troy, Tyler P.; Nakajima, Masakazu; Nauta, Klaas; Varberg, Thomas D.; Metha, Gregory F.; Lucas, Nigel T.; Schmidt, Timothy W.

    2008-07-01

    The first optical spectrum of an isolated polycyclic aromatic hydrocarbon large enough to survive the photophysical conditions of the interstellar medium is reported. Vibronic bands of the first electronic transition of the all-benzenoid polycyclic aromatic hydrocarbon hexa-peri-hexabenzocoronene were observed in the 4080-4530 Å range by resonant 2-color 2-photon ionization spectroscopy. The strongest feature at 4264 Å is estimated to have an oscillator strength of f=1.4×10-3, placing an upper limit on the interstellar abundance of this polycyclic aromatic hydrocarbon at 4×1012 cm-2, accounting for a maximum of ~0.02% of interstellar carbon. This study opens up the possibility to rigorously test neutral polycyclic aromatic hydrocarbons as carriers of the diffuse interstellar bands in the near future.

  2. IMPORTANCE OF BLACK CARBON IN DISTRIBUTION AND BIOACCUMULATION MODELS OF POLYCYCLIC AROMATIC HYDROCARBONS IN CONTAMINATED MARINE SEDIMENTS

    EPA Science Inventory

    The roles and relative importance of nonpyrogenic organic carbon (NPOC) and black carbon (BC) as binding phases of polycyclic aromatic hydrocarbons (PAHs) were assessed by their ability to estimate pore water concentrations and biological uptake in various marine sediments. Sedim...

  3. IMPORTANCE OF MATERNAL TRANSFER OF THE PHOTOREACTIVE POLYCYCLIC AROMATIC HYDROCARBON FLUORANTHENE FROM BENTHIC ADULT BIVALVES TO THEIR PELAGIC LARVAE

    EPA Science Inventory

    Laboratory experiments were conducted to determine if maternal transfer of polycyclic aromatic hydrocarbons (PAHs) from benthic adult bivalves could result in phototoxicity to their pelagic larvae when exposed to ultraviolet light (UV). In these experiments, adult bivalves were e...

  4. PHOTOACTIVATED POLYCYCLIC AROMATIC HYDROCARBON TOXICITY IN MEDAKA (ORYZIAS LATIPES) EMBRYOS: RELEVANCE TO ENVIRONMENTAL RISK IN CONTAMINATED SITES

    EPA Science Inventory

    The hazard for photoactivated toxicity of polycyclic aromatic hydrocarbons (PAHs) has been clearly demonstrated; however, to our knowledge, the risk in contaminated systems has not been characterized. To address this question, a median lethal dose (LD50) for fluoranthene photoa...

  5. BROMO- AND BROMOCHLORO-POLYNUCLEAR AROMATIC HYDROCARBONS, DIOXINS AND DIBENZOFURANS IN MUNICIPAL INCINERATOR FLY ASH (JOURNAL VERSION)

    EPA Science Inventory

    A fly ash sample found to contain polychlorinated dioxins and dibenzofurans was analyzed for brominated analytes. Bromochloro-polynuclear aromatic hydrocarbons, dioxins and dibenzofurans, as well as bromo PAH were found in ppt to ppb concentrations. Analytical results were confir...

  6. Detection of aromatic hydrocarbons in the atmosphere at ppt levels

    NASA Astrophysics Data System (ADS)

    Whalen, M.; Driscoll, J. N.; Wood, C. D.

    A new method has been described and evaluated which will detect ppt levels of hydrocarbons in the atmosphere. An automatic GC was used with a concentrator and a photoionization detector to measure benzene, toluene and xylene. The values obtained in the Boston, MA area were in good agreement with the literature value. The BTX data were compared with simultaneous CO 2 data and some interesting features were observed. Good correlation was obtained with simultaneous CO 2 data during rush hour traffic and no correlation during the early morning hours when the BTX values would rise while the CO 2 values decreased to their ambient levels of 350 ppm.

  7. Calculations of Henry's law constants for adsorption of aromatic hydrocarbons on a graphitic carbon surface

    SciTech Connect

    McConnell, C.L.; Rybolt, T.R. (Univ. of Tennessee, Chattanooga, TN (United States))

    1994-01-01

    Correlations were developed and used to calculate energetic and structural parameters which, in turn, were used to calculate Henry's law constants for the adsorption of a series of aromatic hydrocarbons on a graphitic carbon surface. The adsorption energetic parameter was correlated with a ratio involving the critical temperature divided by the square root of the critical pressure of the adsorbate molecule. The structural parameter was correlated with the cross-sectional molecular area obtained from available molecular modeling software, CAChe. Calculations of Henry's law constants per unit surface area were compared to available experimental values for 17 aromatic hydrocarbons divided into groups of mono-substituted benzene and methyl-substituted benzene. This approach could be used to predict the extent adsorption in the Henry's law region using only adsorbate molecular properties where correlations have been established for a series of molecules of similar structure. 11 refs., 3 figs., 4 tabs.

  8. Air monitoring of aromatic hydrocarbons during automobile spray painting for developing change schedule of respirator cartridges.

    PubMed

    Jahangiri, Mehdi; Adl, Javad; Shahtaheri, Seyed Jamaleddin; Kakooe, Hossein; Rahimi Forushani, Abbas; Ganjali, Mohammad Reza

    2014-01-01

    In the absence of End of Service Life Indicator (ESLI), a cartridge change schedule should be established for ensuring that cartridges are changed before their end of service life. Factors effecting service life of cartridges were evaluated, including the amount of atmospheric contamination with aromatic hydrocarbon vapors in the workplace, temperature, and relative humidity of the air. A new change schedule was established based on comparing the results of air monitoring and workplace conditions, laboratory experiment, and the NIOSH MultiVapor software. Spray painters were being exposed to aromatic hydrocarbons in a range exceeding occupational exposure limits. The cartridge change schedule was not effective and could no longer provide adequate protection against organic contaminants for sprayers. Change schedules for respirator cartridges should be reduced from 16-24 hours to 4 hours. NIOSH's service life software program could be applied to developing cartridge change schedules. PMID:24468234

  9. Air monitoring of aromatic hydrocarbons during automobile spray painting for developing change schedule of respirator cartridges

    PubMed Central

    2014-01-01

    In the absence of End of Service Life Indicator (ESLI), a cartridge change schedule should be established for ensuring that cartridges are changed before their end of service life. Factors effecting service life of cartridges were evaluated, including the amount of atmospheric contamination with aromatic hydrocarbon vapors in the workplace, temperature, and relative humidity of the air. A new change schedule was established based on comparing the results of air monitoring and workplace conditions, laboratory experiment, and the NIOSH MultiVapor software. Spray painters were being exposed to aromatic hydrocarbons in a range exceeding occupational exposure limits. The cartridge change schedule was not effective and could no longer provide adequate protection against organic contaminants for sprayers. Change schedules for respirator cartridges should be reduced from 16–24 hours to 4 hours. NIOSH’s service life software program could be applied to developing cartridge change schedules. PMID:24468234

  10. Renal cancer risk and occupational exposure to polycyclic aromatic hydrocarbons and plastics

    PubMed Central

    Karami, Sara; Boffetta, Paolo; Brennan, Paul; Stewart, Patricia A.; Zaridze, David; Matveev, Vsevolod; Janout, Vladimir; Kollarova, Helena; Bencko, Vladimir; Navratilova, Marie; Szeszenia-Dabrowska, Neonila; Mates, Dana; Gromiec, Jan P.; Sobotka, Roman; Chow, Wong-Ho; Rothman, Nathaniel; Moore, Lee E.

    2011-01-01

    Objective To investigate whether occupational exposure to polycyclic aromatic hydrocarbons and certain plastic monomers increased renal cell carcinomas (RCC) risk. Methods Unconditional logistic regression was used to calculate RCC risk in relation to exposure. Results No association between RCC risk and having ever been occupationally exposed to any polycyclic aromatic hydrocarbons or plastics was observed. Duration of exposure and average exposure also showed no association with risk. Suggestive positive associations between RCC risk and cumulative exposure to styrene (P-trend = 0.02) and acrylonitrile (P-trend = 0.06) were found. Cumulative exposure to petroleum/gasoline engine emissions was inversely associated with risk (P-trend = 0.02). Conclusions Results indicate a possible association between occupational styrene and acrylonitrile exposure and RCC risk. Additional studies are needed to replicate findings, as this is the first time these associations have been reported and they may be due to chance. PMID:21270648

  11. [Estimation of gas chromatographic retention index for polycyclic aromatic hydrocarbons using VMDE].

    PubMed

    Zhou, L P; Xia, Z N; Li, B Y; Liu, S S; Li, H; He, M; Li, Z L

    2001-01-01

    A novel molecular distance-edge vector with 6 parameters was calculated for 100 polycyclic aromatic hydrocarbons (PAHs) based on the molecular interaction theory. It was found that there was a good linear relationship between the molecular distance-edge vector (VMDE) and the gas chromatographic retention index for the 100 PAHs, and the molecular modelling equation for the quantitative structure-retention relationship (QSRR) can be expressed as follows: IR = a + b VMDE, n = 100, r = 0.988, where a and b represent regression coefficients. The regression results showed that the molecular distance-edge vector is in good agreement with the results of molecular polarizability index to the gas chromatographic retention index for the polycyclic aromatic hydrocarbons. PMID:12541841

  12. Near-Infrared Spectroscopy of Nitrogenated Polycyclic Aromatic Hydrocarbon Cations from 0.7 to 2.5 mum

    Microsoft Academic Search

    Andrew L. Mattioda; Lindsay Rutter; John Parkhill; Martin Head-Gordon; Timothy J. Lee; Louis J. Allamandola

    2008-01-01

    The near-infrared (NIR) spectra and absolute band strengths of 10 nitrogenated polycyclic aromatic hydrocarbon (PANH) radical cations isolated in an argon matrix are presented and compared with the spectra of their parent polycyclic aromatic hydrocarbon (PAH) radical cations. The 0.7-2.5 mum (14,500-4000 cm-1) spectrum for the open-shell cation forms of two nitrogenated anthracenes (C13H9N and C 12H8N2), four isomeric nitrogenated

  13. Characterization of the H4IIE Rat Hepatoma Cell Bioassay for Evaluation of Environmental Samples Containing Polynuclear Aromatic Hydrocarbons (PAHs)

    Microsoft Academic Search

    K. L. Willett; P. R. Gardinali; J. L. Sericano; T. L. Wade; S. H. Safe

    1997-01-01

    .   The H4IIE rat hepatoma cell bioassay has been extensively used to assess the toxic equivalents (TEQs) of complex mixtures\\u000a of halogenated aromatic hydrocarbons in environmental samples. However, there is often a discrepancy between bioassay induction\\u000a results and toxic equivalents calculated from chemical analysis of samples; the former generally yield higher bioassay-TEQs.\\u000a Polynuclear aromatic hydrocarbons (PAHs) are a class of

  14. Derivation of a chronic reference dose and reference concentration for trimethylbenzenes and C9 aromatic hydrocarbon solvents

    Microsoft Academic Search

    Michael J. Firth

    2008-01-01

    Trimethylbenzenes (TMBs) and C9 aromatic hydrocarbon solvents are structurally similar and have similar toxicity. Based on a review of the entire TMB and C9 aromatic hydrocarbon solvents toxicology database, oral and inhalation studies were identified to serve as the basis for a Reference dose (RfD) and Reference concentrations (RfC). The RfD and RfC were derived using standard USEPA methods and

  15. Secondary Aerosol Formation from Oxidation of Aromatics Hydrocarbons by Cl atoms

    NASA Astrophysics Data System (ADS)

    Cai, X.; Griffin, R.

    2006-12-01

    Aerosol Formation From the Oxidation of Aromatic Hydrocarbons by Chlorine Atmospheric secondary organic aerosol (SOA) affects regional and global air quality. The formation mechanisms of SOA via the oxidation of volatile organic compounds by hydroxyl radicals, ozone, and nitrate radicals have been studied intensively during the last decade. Chlorine atoms (Cl) also have been hypothesized to be effective oxidants in marine and industrially influenced areas. Recent work by the authors has indicated that significant amounts of SOA are formed from the oxidation of monoterpenes by Cl. Aromatic hydrocarbons are important for generation of both SOA and ozone in urban areas because of their large emission rates and high reactivity. The goal of this work was to quantify the SOA formation potentials of two representative aromatic hydrocarbons through laboratory chamber experiments in which oxidation was initiated by Cl. The system constructed for this study includes an experimental chamber, a gas chromatograph for quantification of aromatic mixing ratios, a Scanning Mobility Particle Spectrometer to measure SOA size distributions, a zero air generator, and an illuminating system. The model aromatic hydrocarbons chosen for this study are toluene and m-xylene. Aerosol yields are estimated based on measured aerosol volume concentration, the concentration of consumed hydrocarbon, and estimation of wall loss of the newly formed aerosol. Toluene and m-xylene exhibit similar SOA yields from the oxidation initiated by Cl. The toluene SOA yield from Cl-initiated oxidation, however, depends on the ratio between the mixing ratios of the initial chlorine source and toluene in the chamber. For toluene experiments with higher such ratios, SOA yields vary from 0.05 to 0.079 for generated aerosol ranging from 4.2 to12.0 micrograms per cubic meter. In the lower ratio experiments, SOA yields are from 0.033 to 0.064, corresponding to generated aerosol from 3.0 to 11.0 micrograms per cubic meter. The m-xylene SOA yield ranges from 0.04 to 0.08 for aerosol in the range of 4.0 to 12.0 micrograms per cubic meter. These yields are generally comparable to those from photooxidation. In marine and industrial areas, SOA formation from the Cl- initiated oxidation of the studied common aromatics is likely to be most important in the early morning.

  16. Uptake of gaseous aromatic hydrocarbons by non-growing ice crystals

    NASA Astrophysics Data System (ADS)

    Fries, Elke; Haunold, Werner; Jaeschke, Wolfgang; Hoog, Ines; Mitra, Subir K.; Borrmann, Stephan

    Laboratory studies were performed in a walk-in cold chamber to investigate the uptake of aromatic hydrocarbons by non-growing ice crystals at -20 °C. Dendritic ice crystals were grown by vapor deposition and exposed to organic gases (benzene, toluene, ethylbenzene, m/ p-xylene, o-xylene, n-propylbenzene, 4-ethyltoluene, 1,3,5-trimethylbenzene, tert-butylbenzene, 1,2,4-trimethylbenzene, and 1,2,3-trimethylbenzene) at gas-phase concentrations between 2.8 and 33.1 ?g m -3. During all exposure experiments, the gas/air stream was maintained at ice saturation to avoid ice crystal growth or evaporation. An analytical method comprising of solid-phase-micro-extraction followed by gas chromatography/mass spectrometry (SPME/GC-MS) was applied, which allows detection of organic compounds in melted ice at 0.025 ng g ice-1. The SPME/GC-MS method was an appropriate tool to determine the uptake of organic compounds by ice crystals at the applied gas-phase concentrations. However, it was not possible to detect any of the test substances in ice samples after exposure. No adsorption could be detected by increasing gas-phase concentrations. Neither increasing exposure time nor lowering flow rate of the carrier gas caused detectable adsorption effects of aromatic compounds on ice. Our results indicate that adsorption of aromatic hydrocarbons is either insignificant or highly reversible at -20 °C. These findings are consistent with reversible adsorption processes reported already for many oxygenated organic compounds like alcohols, acids, and aldehydes. Although the specific surface area of dendritic ice crystals is large, the results of our study demonstrate that gas uptake by ice surfaces is negligible for the removal of aromatic hydrocarbons in the atmosphere. This is an indication that the occurrence of aromatic hydrocarbons in precipitation cannot be explained by surface adsorption. There must be another accumulation process leading to concentrations of aromatic hydrocarbons found in field studies which is still unknown.

  17. Polycyclic aromatic hydrocarbon (PAH) contamination in the urban topsoils of Shenyang, China

    Microsoft Academic Search

    Yuebing Sun; Guohong Sun; Qixing Zhou; Yingming Xu; Lin Wang; Xuefeng Liang; Yang Sun; Xu Qin

    2012-01-01

    Polycyclic aromatic hydrocarbons (PAHs) in the surface urban soils of Shenyang in Northeastern China were investigated. The total concentration of the PAHs ranged from 0.09 to 8.35 mg kg, with an average value of 1.51 ± 1.64 mg kg. 3–5-ring PAHs accounted for 90% of total PAHs. The functional areas, such as the industrial regions (4.95 mg kg) and main roads (1.56 mg kg),

  18. Isolation of adherent polycyclic aromatic hydrocarbon (PAH)-degrading bacteria using PAH-sorbing carriers

    Microsoft Academic Search

    LEEN BASTIAENS; DIRK SPRINGAEL; PIERRE WATTIAU; HAUKE HARMS; RUPERT DEWACHTER; HUBERT VERACHTERT; LUDO DIELS

    2000-01-01

    Two different procedures were compared to isolate polycyclic aromatic hydrocarbon (PAH)-utilizing bacteria from PAH-contaminated soil and sludge samples, i.e., (i) shaken enrichment cultures in liquid mineral medium in which PAHs were supplied as crystals and (ii) a new method in which PAH degraders were enriched on and recovered from hydrophobic membranes containing sorbed PAHs. Both techniques were successful, but selected

  19. Degradation of polycyclic aromatic hydrocarbons in soil by a two-step sequential treatment

    Microsoft Academic Search

    Leticia Pizzul; Åsa Sjögren; María del Pilar Castillo; John Stenström

    2007-01-01

    The objectives of this work were to isolate the microorganisms responsible for a previously observed degradation of polycyclic\\u000a aromatic hydrocarbons (PAH) in soil and to test a method for cleaning a PAH-contaminated soil. An efficient PAH degrader was\\u000a isolated from an agricultural soil and designated as Mycobacterium LP1. In liquid culture, it degraded phenanthrene (58%), pyrene (24%), anthracene (21%) and

  20. Aromatic Hydrocarbons in Biota from the Detroit River and Western Lake Erie

    Microsoft Academic Search

    Chris D. Metcalfel; Tracy L. Metcalfe; Geoffrey Riddle; G. Douglas Haffner

    1997-01-01

    Polynuclear aromatic hydrocarbons (PAHs) and PCBs in zebra mussels were elevated to concentrations greater than 5,000 ng\\/g lipid and 15,000 ng\\/g lipid, respectively, at the Ambassador Bridge in the Detroit River and concentrations gradually declined at downstream locations, which included three stations in the western basin of Lake Erie (Middle Sister Island, East Sister Island, Pelee Island). PCB concentrations in

  1. Interlaboratory comparison of methods used for analysing polycyclic aromatic hydrocarbons (PAHs) in soil samples

    Microsoft Academic Search

    Iris Blankenhorn; Dirk Meijer; Robert J. Delft

    1992-01-01

    In view of the investigation of contaminated model sites in Baden-Württemberg an inter-laboratory comparison was organized for the methods used for analysing polycyclic aromatic hydrocarbons (PAHs). The laboratories performing chemical and physical analyses at the model sites participated at the request of the Landesanstalt für Umweltschutz, Baden-Württemberg. This inter-laboratory comparison was meant as a first laboratory evaluation, and not as

  2. Degradation of Polycyclic Aromatic Hydrocarbons (PAHs) by Indigenous Mixed and Pure Cultures Isolated from Coastal Sediments

    Microsoft Academic Search

    Mahasin G. Tadros; Joseph B. Hughes

    1997-01-01

    The goal of this paper was to quantify and characterize microorganisms (bacteria) in sediment samples contaminated with polycyclic\\u000a aromatic hydrocarbons (PAHs: fluorene and naphthalene). The isolated organisms were evaluated for their ability to degrade\\u000a PAHs compounds. The results indicated that the total number of recovered heterotrophic colony forming units was higher than\\u000a zone forming units produced by the PAHs compounds.

  3. Evaluation of bacterial strategies to promote the bioavailability of polycyclic aromatic hydrocarbons

    Microsoft Academic Search

    A. R. Johnsen; U. Karlson

    2004-01-01

    Polycyclic aromatic hydrocarbon (PAHs)-degrading bacteria may enhance the bioavailability of PAHs by excreting biosurfactants, by production of extracellular polymeric substances, or by forming biofilms. We tested these hypotheses in pure cultures of PAHs-degrading bacterial strains. Most of the strains did not substantially reduce the surface tension when grown on PAHs in liquid shaken cultures. Thus, pseudo-solubilization of PAHs in biosurfactant

  4. Polycyclic aromatic hydrocarbons in sediments and mussels of the western Mediterranean Sea

    Microsoft Academic Search

    Pascale Baumard; Hélène Budzinski; Philippe Garrigues

    1998-01-01

    The distribution of polycyclic aromatic hydrocarbons (PAHs) has been investigated in superficial sediments and mussels (Mytilus galloprovincialis) of the western Mediterranean sea. The analyses were performed by gas chromatography coupled to mass spectrometry (GC-MS). The PAH concentrations ranged from 1 to 20,500 ng\\/g in the sediments. Different molecular indices allowed differentiation between the different pollutant sources. On the French coast,

  5. Vaporous and particulate?bound polycyclic aromatic hydrocarbons in Chinese incense smoke

    Microsoft Academic Search

    1998-01-01

    In this study, we determined polycyclic aromatic hydrocarbons (PAHs) in incense smoke by high performance liquid Chromatograph equipped with a fluorescence detector. The total yield of PAHs was 94.07 ug to 111.65 ?g per gram incense burned and varied with four kinds of incenses. All vaporous PAHs were those with molecular weight (MW) less than 202.26, the MW of pyrene.

  6. Distribution of polycyclic aromatic hydrocarbons (PAHs) in floodplain soils of the Mosel and Saar River

    Microsoft Academic Search

    Carmen Pies; Yi Yang; Thilo Hofmann

    2007-01-01

    Background, Aim and Scope  Polycyclic aromatic hydrocarbons (PAHs) have gained serious attention in the scientific community due to their persistence\\u000a and toxic potential in the environment. PAHs may pose a risk to ecosystem health. Along the Mosel River\\/Germany, a tributary\\u000a of the river Rhine, PAHs were found at significantly high concentrations (> 20 mg kg?1, German national guideline value Z2, LAGA

  7. Composition and distribution of polycyclic aromatic hydrocarbon contamination in surficial marine sediments from Kitimat Harbor, Canada

    Microsoft Academic Search

    Christopher D. Simpson; Andrew A. Mosi; William R. Cullen; Kenneth J. Reimer

    1996-01-01

    Surficial marine sediments from 20 sites within the Kitimat fjord system were analyzed for polycyclic aromatic hydrocarbons (PAHs). Levels of the sum of the 16 USEPA priority pollutant PAHs varied from below detection limits (ca. 1 ?g·g?1) to over 10000 ?g·g?1. Sediment PAH levels were highest in the immediate vicinity of a large aluminum smelter at the head of Kitimat

  8. Effects of ambient temperature on aspects of airborne polycyclic aromatic hydrocarbons

    Microsoft Academic Search

    Hiroyasu Yamasaki; Kazuhiro Kuwata; Hiroko Miyamoto

    1982-01-01

    Three- to six-ring polycyclic aromatic hydrocarbons in the vapor phase (PAHs\\/sub vap\\/) and in the particulate phase (PAHs\\/sub pat) and total suspended particulate (TSP) in ambient air were sampled and determined year-round. At ambient temperature levels, substantial amounts of three-to five-ring PAHs were found in the vapor phase depending upon temperature (T, K) and the six-ring PAHs were all found

  9. Contamination by polycyclic aromatic hydrocarbons in the Jiulong River Estuary and Western Xiamen Sea, China

    Microsoft Academic Search

    K Maskaoui; J. L Zhou; H. S Hong; Z. L Zhang

    2002-01-01

    The distribution of 16 polycyclic aromatic hydrocarbons (PAHs) was determined in water, sediment and pore water of the Jiulong River Estuary and Western Xiamen Sea, China. Total PAH concentrations varied from 6.96 to 26.9 ?g\\/l in water, 59–1177 ng\\/g dry weight in surficial sediments, and 158–949 ?g\\/l in pore water. The PAHs were present in higher levels in pore water

  10. Oxidation of Polycyclic Aromatic Hydrocarbons (PAH) by Laccase of Trametes Versicolor

    Microsoft Academic Search

    Andrzej Majcherczyk; Christian Johannes; Aloys Hüttermann

    1998-01-01

    Laccase of Trametes versicolor was able to oxidize in vitro most of the 14 polycyclic aromatic hydrocarbons (PAH) tested. Acenaphthylene was removed by 37% followed by anthracene and benzo[a]pyrene which were oxidized by 18 and 19%, respectively. Lower but significant oxidation of about 10% was found for eight additional PAH: acenaphthene, fluoranthene, pyrene, benzo[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, and perylene. Naphthalene,

  11. Selective Fluorescence Detection of Polycyclic Aromatic Hydrocarbons in Environmental Tobacco Smoke and Other Airborne Particles

    Microsoft Academic Search

    K. R. R. Mahanama; L. A. Gundel; J. M. Daisey

    1994-01-01

    An analytical method is described for the simultaneous quantitation of polycyclic aromatic hydrocarbons [PAHs] and alkyl-derivatives [alkyl-PAHs] in “real world” samples using microbore reversed-phase high performance liquid chromatography in conjunction with two programmable fluorescence detectors. Sensitivity and selectivity were enhanced by analyzing PAHs under their optimum fluorescence wavelengths. The accuracy of the analytical method was evaluated by determination of PAHs

  12. Enhanced sorption of polycyclic aromatic hydrocarbons by soil amended with biochar

    Microsoft Academic Search

    Baoliang Chen; Miaoxin Yuan

    2011-01-01

    Purpose  Polycyclic aromatic hydrocarbon (PAHs) are ubiquitous pollutants in agricultural soils in China. Biochar is the charred product\\u000a of biomass pyrolysis, which is widely applied to soils to sequestrate atmospheric carbon dioxide and guarantees a long-term\\u000a benefit for soil fertility. Knowledge about the impacts of various biochars on soil sorption affinity remains obscure. In\\u000a this study, we evaluated the effects of

  13. Blood Levels of Polycyclic Aromatic Hydrocarbons in Children of Lucknow, India

    Microsoft Academic Search

    Vipul K. Singh; Devendra K. Patel; S. Ram; N. Mathur; M. K. J. Siddiqui; Jai Raj Behari

    2008-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are compounds with two or more fused benzene rings produced by incomplete combustion\\u000a of organic substances involved in natural and anthropogenic processes. Children are exposed to these compounds through inhalation,\\u000a dietary ingestion, and, also, soil at the playground. It has been well established that PAHs have carcinogenic, mutagenic,\\u000a and teratogenic effects. Considering possible health risks due

  14. Sources of heavy metals and polycyclic aromatic hydrocarbons in urban stormwater runoff

    Microsoft Academic Search

    Jeffrey N. Brown; Barrie M. Peake

    2006-01-01

    Polycyclic aromatic hydrocarbons (PAHs) and heavy metals were measured in road debris collecting in urban areas and in the suspended sediment (SS) component of runoff from two stormwater catchments in Dunedin, New Zealand. Levels in the road debris ranged from 119–527 ?g\\/g for lead, 50–464 ?g\\/g for copper, 241–1 325 ?g\\/g for zinc and 1.20–11.6 ?g\\/g for ?16PAH. The SS

  15. Altered Tissue Levels of Vitamin a by Selected Polycyclic Aromatic Hydrocarbons (PAHs)

    Microsoft Academic Search

    Li-Chuan Chen; Isabelle Berberian; Howard P. Glauert; Larry W. Robertson; Ching K. Chow

    1994-01-01

    The purpose of this study was to determine the effects of certain polycyclic aromatic hydrocarbons (PAHs) of known carcinogenic potential on rat tissue levels of retinol and retinyl esters. Male Sprague-Dawley rats fed a vitamin A-adequate diet (1.3 mg of retinyl palmitate\\/kg) for 30 days were intraperitoneally administered three injections of one of the following four PAHs: carcinogenic 3-methylcholanthrene (MC),

  16. Flotation of polycyclic aromatic hydrocarbons coprecipitated with aluminum hydroxide containing sodium dodecyl sulfate and magnesium

    Microsoft Academic Search

    Tohru Saitoh; Seiichi Matsushima; Masataka Hiraide

    2007-01-01

    A simple and efficient method for concentrating polycyclic aromatic hydrocarbons (PAHs) in water was developed. Al(III) and an anionic surfactant, sodium dodecyl sulfate (SDS), were added into the aqueous sample solution. Subsequently, the solution pH was adjusted to 7 by adding 2 and 0.1mol\\/L sodium hydroxide solutions to form aluminum hydroxide precipitaties. Hydrophobic PAHs were well incorporated into the hydrophobic

  17. Fluorescence optosensors based on different transducers for the determination of polycyclic aromatic hydrocarbons in water

    Microsoft Academic Search

    J. F. Fernández-Sánchez; A. Segura-Carretero; J. M. Costa-Fernández; N. Bordel; R. Pereiro; C. Cruces-Blanco; A. Sanz-Medel; A. Fernández-Gutiérrez

    2003-01-01

    .  This paper presents the development of two optosensors for the determination of four polycyclic aromatic hydrocarbons (anthracene, benzo[a]pyrene, fluoranthene and benzo[b]fluoranthene) using a photomultiplier device and an intensified coupled charge device (ICCD) as optical transducers, respectively. These optosensors are based on the on-line immobilization of the analytes onto a non-ionic resin solid support (Amberlite XAD-4) in a continuous flow system,

  18. Phototoxicity of non-carcinogenic polycyclic aromatic hydrocarbons in aquatic organisms

    SciTech Connect

    Kagan, J.; Kagan, E.D.; Kagan, I.A.; Kagan, P.A.; Quigley, S.

    1985-01-01

    Anthracene, fluoranthene, and pyrene are phototoxic in Daphnia magna, Artemia salina, first instar larvae of Aedes aegypti, late embryonic forms of Rana pipiens, and fish (Pimephales promelas). Since polycyclic aromatic hydrocarbons are generated in the combustion processes held responsible for the damages of acid rain, and they are introduced into the environment through other means as well, the high phototoxicity of the major pollutants, which are not carcinogenic, suggests that greater attention must be given to their environmental significance.

  19. Distribution and biodegradation of polycyclic aromatic hydrocarbons in contaminated sites of Hisar (India)

    Microsoft Academic Search

    Kiran Bishnoi; Umashanker Sain; Rajender Kumar; Rajesh Singh; Narsi R Bishnoi

    2009-01-01

    Fifty-two soil samples were collected from various location of the Hisar city. These samples were analysed for six polycyclic aromatic hydrocarbons (naphthalene, acenaphthene, phenanthrene, anthracene, fluoranthene, and pyrene). Total mean concentration of six PAHs varied from 51.79 to 148.82 mg kg-1 dry weight of the soil, PAH concentration was higher in soil samples from local auto market while lower concentration

  20. Effects of enrichment with phthalate on polycyclic aromatic hydrocarbon biodegradation in contaminated soil

    Microsoft Academic Search

    David R. Singleton; Stephen D. Richardson; Michael D. Aitken

    2008-01-01

    The effect of enrichment with phthalate on the biodegradation of polycyclic aromatic hydrocarbons (PAH) was tested with bioreactor-treated\\u000a and untreated contaminated soil from a former manufactured gas plant (MGP) site. Soil samples that had been treated in a bioreactor\\u000a and enriched with phthalate mineralized 14C-labeled phenanthrene and pyrene to a greater extent than unenriched samples over a 22.5-h incubation, but

  1. Synthesis, electronic properties and WOLED devices of planar phosphorus-containing polycyclic aromatic hydrocarbons.

    PubMed

    Riobé, François; Sz?cs, Rózsa; Bouit, Pierre-Antoine; Tondelier, Denis; Geffroy, Bernard; Aparicio, Fátima; Buendía, Julia; Sánchez, Luis; Réau, Régis; Nyulászi, László; Hissler, Muriel

    2015-04-20

    We describe the synthesis and the physical properties of polyaromatic hydrocarbons (PAHs) containing a phosphorus atom at the edge. In particular, the impact of the successive addition of aromatic rings on the electronic properties was investigated by experimental (UV/Vis absorption, fluorescence, cyclic voltammetry) and theoretical studies (DFT). The physical properties recorded in solution and in the solid state showed that the P-containing PAHs exhibit properties expected for an emitter in white organic light-emitting diodes (WOLEDs). PMID:25760307

  2. Atmospheric polycyclic aromatic hydrocarbons (PAHs) in the urban air of Delhi during 2003

    Microsoft Academic Search

    Homdutt Sharma; V. K. Jain; Zahid H. Khan

    2008-01-01

    Atmospheric concentrations of polycyclic aromatic hydrocarbons (PAHs) in Delhi were evaluated to study particulate PAHs profiles\\u000a during the different seasons of 2003. Samples of urban suspended particulate matter were collected during January 2003 to\\u000a December 2003 at three locations (Okhla, Dhaulakuan and Daryaganj), using a high volume sampler provided with glass fiber\\u000a filters. Samples were analyzed using the gas chromatography

  3. Global fate and distribution of polycyclic aromatic hydrocarbons emitted from Europe and Russia

    Microsoft Academic Search

    Aissa M. Sehili; Gerhard Lammel

    2007-01-01

    The long-range atmospheric transport (LRT) of polycyclic aromatic hydrocarbons (PAHs) is not fully understood and has hardly been addressed by model studies. By model experiments the LRT of PAH emissions into air from Europe and Russia is studied testing several scenarios of gas–particle partitioning and degradability by reaction with ozone and the hydroxyl and nitrate radicals for two PAHs, benzo[a]pyrene

  4. Observation of Indigenous Polycyclic Aromatic Hydrocarbons in ‘Giant’ carbonaceous Antarctic Micrometeorites

    Microsoft Academic Search

    S. J. Clemett; X. D. F. Chillier; S. Gillette; R. N. Zare; M. Maurette; C. Engrand; G. Kurat

    1998-01-01

    Two-step laser desorption\\/laser ionization mass spectrometry (µL2MS) was used to establish the nature and mass distribution of polycyclic aromatic hydrocarbons (PAHs) in fragments of fifteen ‘giant’ (~200 µm) carbonaceous Antarctic micrometeorites (AMMs). Detectable concentrations of PAHs were observed in all AMMs showing a fine-grained matrix. The range of integrated PAH signal intensities varied between samples by over two orders of

  5. Exposure to polycyclic aromatic hydrocarbons in petrochemical industries by measurement of urinary 1-hydroxypyrene

    Microsoft Academic Search

    P J Boogaard; N J van Sittert

    1994-01-01

    Biological monitoring of exposure of workers to polycyclic aromatic hydrocarbons (PAHs) in petrochemical industries was performed by the measurement of urinary excretion of 1-hydroxypyrene. In 121 of the 462 workers studied (both smokers and non-smokers) who had had no recent occupational exposure to PAHs a median 1-hydroxypyrene concentration of 0.21 micrograms\\/g creatinine was found. The upper limit of the 95%

  6. Studies on aromatic hydrocarbon quinone metabolism and DT-Diaphorase function in liver of fish species

    Microsoft Academic Search

    Philippe Lemaire; Joachim Sturve; Lars Förlin; David R. Livingstone

    1996-01-01

    Studies were carried out to examine the role of aromatic hydrocarbon (AH)-quinone metabolism and DT-diaphorase (quinone oxidoreductase; EC 1.6.99.2; DTD) function in pollution-caused oxidative damage in fish. Redox cycling of quinones to produce reactive oxygen species (ROS) was studied by oxygen consumption and oxidation of the hydroxyl radical scavenger 2-keto-4-methiolbutyric acid. NADH-dependent redox cycling by hepatic microsomes of flounder (Platichthys

  7. Combustion Kinetics and Emission Characteristics of Polycyclic Aromatic Hydrocarbons from Polylactic Acid Combustion

    Microsoft Academic Search

    Yi-Chi Chien; Chenju Liang; Shou-Heng Liu; Shu-Hua Yang; Krzysztof Gaska; Lingjuan Wang; Edgar Oviedo-Rondon; John Small; Zifei Liu; Brian Sheldon; Gerald Havenstein; C. Williams; Di Tian; Daniel Cohan; Sergey Napelenok; Michelle Bergin; Yongtao Hu; Michael Chang; Armistead Russell; Ye Xu; Guohe Huang; Xiaosheng Qin; Kuo-Pin Yu; Grace Lee; Guo-Hao Huang; Prabhakar Sharma; Tjalfe Poulsen; William Vizuete; Leiran Biton; Harvey Jeffries; Evan Couzo; Maciej Kryza; Malgorzata Werner; Marek Blas; Anthony Dore; Mieczyslaw Sobik; Daniel Olsen; Morgan Kohls; Gregg Arney; Kaushlendra Singh; L. Risse; K. C. Das; John Worley; Sidney Thompson; Bryan Comer; James Corbett; J. Hawker; Karl Korfmacher; Earl Lee; Chris Prokop; James Winebrake

    2010-01-01

    This study investigates the combustion kinetics and emission factors of 16 U.S. Environmental Protection Agency priority polycyclic aromatic hydrocarbons (PAHs) in polylactic acid (PLA) combustion. Experimentally, two reactions are involved in the PLA combustion process that potentially result in the release of lactide, acetaldehyde, and n-hexaldehyde. The products may continuously be oxidized to form carbon dioxide (CO2) and some PAHs

  8. Chlorinated Polycyclic Aromatic Hydrocarbons in Sediments from Industrial Areas in Japan and the United States

    Microsoft Academic Search

    Yuichi Horii; Takeshi Ohura; Nobuyoshi Yamashita; Kurunthachalam Kannan

    2009-01-01

    Chlorinated polycyclic aromatic hydrocarbons (ClPAHs) are widespread environmental pollutants in the urban environment. Nevertheless,\\u000a there is little information available regarding the occurrence and profiles of ClPAHs in environmental matrices. In this study,\\u000a residual concentrations and profiles of 20 individual ClPAHs and 16 US EPA-priority PAHs were determined using high- resolution\\u000a gas chromatography–high-resolution mass spectrometry in sediments from water bodies near

  9. Polycyclic Aromatic Hydrocarbons (PAHs) in Sediments of the White Sea, Russia

    Microsoft Academic Search

    Vladimir M Savinov; Tatiana N Savinova; JoLynn Carroll; Gennady G Matishov; Salve Dahle; Kristoffer Næs

    2000-01-01

    The extent of environmental contamination and sources of polycyclic aromatic hydrocarbon (PAH) compounds to sediments of the White Sea are evaluated and compared with previously published results for adjacent Arctic Sea areas. Concentrations of two- to six-ring PAHs of molecular mass 128–278 including perylene and sediment characteristics are considered in this investigation. Mean ?PAH concentration was 61±34 ng\\/g dw (n=11)

  10. Induction of mixed—function oxidase activity in mouse lymphoid tissues by polycyclic aromatic hydrocarbons

    Microsoft Academic Search

    Guy D. Griffin; B. Zane Egan; Norman E. Lee; Carl A. Burtis

    1986-01-01

    Polycyclic aromatic hydrocarbon (PAH) exposure can cause mixed?function oxidase (MFO) enzyme induction in certain tissues of various organisms. Measurement of such induction might serve as a useful bioindicator of human exposure to PAHs, provided readily obtainable human tissues can be utilized for such measurements.We have investigated the MFO activity in various lymphoid tissues of the C3H mouse as a model

  11. Leaching and microbial treatment of a soil contaminated by sulphide ore ashes and aromatic hydrocarbons

    Microsoft Academic Search

    Alessandro D’Annibale; Vanessa Leonardi; Ermanno Federici; Franco Baldi; Fulvio Zecchini; Maurizio Petruccioli

    2007-01-01

    Contaminated soil from a historical industrial site and containing sulfide ore ashes and aromatic hydrocarbons underwent sequential\\u000a leaching by 0.5 M citrate and microbial treatments. Heavy metals leaching was with the following efficiency scale: Cu (58.7%)\\u000a > Pb (55.1%) > Zn (44.5%) > Cd (42.9%) > Cr (26.4%) > Ni (17.7%) > Co (14.0%) > As (12.4%) > Fe (5.3%) >

  12. Experimental investigation of the effects of polynuclear aromatic hydrocarbons on an estuarine sediment food web

    Microsoft Academic Search

    Kevin R. Carman; John W. Fleeger; Jay C. Meanqb; Steven M. Pomarico; Debra J. McMillin

    1995-01-01

    The influence of polynuclear aromatic hydrocarbons (PAH) on a benthic estuarine sedimentary salt-marsh food web was examined using a microcosm system to simulate natural conditions. Microcosms were dosed with sublethal concentrations of PAH-contaminated sediment collected from a produced-water site at Pass Fourchon, Louisiana, USA (final PAH concentrations ranged from 0.3 to 3 mg PAH\\/kg dry sediment). Bacterial activity, physiological condition

  13. Genotoxic effects of five polycyclic aromatic hydrocarbons in human and rat mammary epithelial cells

    Microsoft Academic Search

    Suneeti S. Mane; Dallas M. Purnell; Ih-chang Hsu

    1990-01-01

    Five polycyclic aromatic hydrocarbons (PAHs) of different carcinogenic activities were evaluated for their effects on DNA synthesis (³HTdR labeling index (L.I.)) of rat and human mammary epithelial cells (MEC) and for their effects on chromosomes in MEC-mediated sister chromatid exchange (SCE) assays. When compared with DMSO-treated cells, exposures of rat MEC to the two most potent carcinogens, i.e., 7,12-dimethylbenz(a)anthracene (DMBA)

  14. Elimination Rate Constants of 46 Polycyclic Aromatic Hydrocarbons in the Unionid Mussel, Elliptio complanata

    Microsoft Academic Search

    W. A. Thorsen; D. Forestier; T. Sandifer; P. R. Lazaro; W. G. Cope; D. Shea

    2004-01-01

    Elimination rate constants (k2), biological half-lives (t1\\/2), and the time required to reach 95% of steady-state (t95) are reported for 46 individual polycyclic aromatic hydrocarbons (PAHs) including both parent and alkyl homologues, for the freshwater unionid mussel, Elliptio complanata. Elimination rate constants generally follow first-order kinetics and range from 0.04\\/day (d) for perylene to 0.26\\/d for 2,6-dimethylnapthalene, half-lives range from

  15. The role of microbial populations in the containment of aromatic hydrocarbons in the subsurface.

    PubMed

    Franzmann, P D; Robertson, W J; Zappia, L R; Davis, G B

    2002-01-01

    A survey of soil gases associated with gasoline stations on the Swan Coastal Plain of Western Australia has shown that 20% leak detectable amounts of petroleum. The fates of volatile hydrocarbons in the vadose zone at one contaminated site, and dissolved hydrocarbons in groundwater at another site were followed in a number of studies which are herein reviewed. Geochemical evidence from a plume of hydrocarbon-contaminated groundwater has shown that sulfate reduction rapidly developed as the terminal electron accepting process. Toluene degradation but not benzene degradation was linked to sulfate reduction. The sulfate-reducing bacteria isolated from the plume represented a new species, Desulfosporosinus meridiei. Strains of the species do not mineralise 14C-toluene in pure culture. The addition of large numbers of cells and sulfate to microcosms did stimulate toluene mineralisation but not benzene mineralisation. Attempts to follow populations of sulfate-reducing bacteria by phospholipid signatures, or Desulfosporosinus meridiei by FISH in the plume were unsuccessful, but fluorescently-labeled polyclonal antibodies were successfully used. In the vadose zone at a different site, volatile hydrocarbons were consumed in the top 0.5 m of the soil profile. The fastest measured rate of mineralisation of 14C-benzene in soils collected from the most active zone (6.5 mg kg(-1) day(-1)) could account for the majority of the flux of hydrocarbon vapourtowards the surface. The studies concluded that intrinsic remediation by subsurface microbial populations in groundwater on the Swan Coastal Plain can control transport of aromatic hydrocarbon contamination, except for the transport of benzene in groundwater. In the vadose zone, intrinsic remediation by the microbial populations in the soil profile can contain the transport of aromatic hydrocarbons, provided the physical transport of gases, in particular oxygen from the atmosphere, is not impeded by structures. PMID:12222956

  16. Bioavailability and potential carcinogenicity of polycyclic aromatic hydrocarbons from wood combustion particulate matter in vitro.

    PubMed

    Gauggel-Lewandowski, Susanne; Heussner, Alexandra H; Steinberg, Pablo; Pieterse, Bart; van der Burg, Bart; Dietrich, Daniel R

    2013-11-25

    Due to increasing energy demand and limited fossil fuels, renewable energy sources have gained in importance. Particulate matter (PM) in general, but also PM from the combustion of wood is known to exert adverse health effects in human. These are often related to specific toxic compounds adsorbed to the PM surface, such as polycyclic aromatic hydrocarbons (PAH), of which some are known human carcinogens. This study focused on the bioavailability of PAHs and on the tumor initiation potential of wood combustion PM, using the PAH CALUX® reporter gene assay and the BALB/c 3T3 cell transformation assay, respectively. For this, both cell assays were exposed to PM and their respective organic extracts from varying degrees of combustion. The PAH CALUX® experiments demonstrated a concentration-response relationship matching the PAHs detected in the samples. Contrary to expectations, PM samples from complete (CC) and incomplete combustion (IC) provided for a stronger and weaker response, respectively, suggesting that PAH were more readily bioavailable in PM from CC. These findings were corroborated via PAH spiking experiments indicating that IC PM contains organic components that strongly adsorb PAH thereby reducing their bioavailability. The results obtained with organic extracts in the cell transformation assay presented the highest potential for carcinogenicity in samples with high PAH contents, albeit PM from CC also demonstrated a carcinogenic potential. In conclusion, the in vitro assays employed emphasize that CC produces PM with low PAH content however with a general higher bioavailability and thus with a nearly similar carcinogenic potential than IC PM. PMID:23796820

  17. Distribution, sources and ecological risks of polycyclic aromatic hydrocarbons in an urban landscape river.

    PubMed

    Ao, Jing; Ruan, Xiaohong; Yan, Yixing; Cai, Mei

    2012-01-01

    The contents of 16 priority water-borne polycyclic aromatic hydrocarbons (PAHs) in water, potential external pollution sources and sediment from the famous landscape of the Qinghuai River were measured by gas chromatography-mass spectrometry (GC-MS). The distribution, composition, source and ecological risk of PAHs were analyzed. The following results were obtained: (1) Benzo[a]pyrene and benzo[ghi] perylene were not detected in all samples. The total contents of 16 priority PAHs (PAH16) varied from 52.5 to 745.3 ng l(-1) with the average of 174.0 ng l(-1) in water, from 96.0 to 1,064.6 ng l(-1) with the average of 329.2 ng l(-1) in potential sources, from 931.7 to 15,295.5 ng g(-1) with the average of 7,133.6 ng g(-1) in sediments. (2) The concentration of PAH16 in water is lower than in sediment and higher rings are more easily detected in sediment. The percentage of higher ring (four- to six-rings) PAHs accounted for more than 55.6% of PAHs in sediment. (3) The value of FLA/(FLA+Pyr) was higher than 0.5 at most sampling points which illustrated the source was related with petrogenic such as liquid fossil fuel combustion. (4) The potential ecosystem risk of low ring PAH for upstream conflux of external Qinhuai River was less than 10%, while it was 10-50% for other sampling points; The four rings PAH shows lower potential ecosystem risk than other ring PAH in this study area; Dibenzo [ah] anthracene (DahA) shows high potential ecosystem risk at all sampling points. PMID:22797219

  18. Deuterium enrichment of polycyclic aromatic hydrocarbons by photochemically induced exchange with deuterium-rich cosmic ices

    NASA Technical Reports Server (NTRS)

    Sandford, S. A.; Bernstein, M. P.; Allamandola, L. J.; Gillette, J. S.; Zare, R. N.

    2000-01-01

    The polycyclic aromatic hydrocarbon (PAH) coronene (C24H12) frozen in D2O ice in a ratio of less than 1 part in 500 rapidly exchanges its hydrogen atoms with the deuterium in the ice at interstellar temperatures and pressures when exposed to ultraviolet radiation. Exchange occurs via three different chemical processes: D atom addition, D atom exchange at oxidized edge sites, and D atom exchange at aromatic edge sites. Observed exchange rates for coronene (C24H12)-D2O and d12-coronene (C24D12)-H2O isotopic substitution experiments show that PAHs in interstellar ices could easily attain the D/H levels observed in meteorites. These results may have important consequences for the abundance of deuterium observed in aromatic materials in the interstellar medium and in meteorites. These exchange mechanisms produce deuteration in characteristic molecular locations on the PAHs that may distinguish them from previously postulated processes for D enrichment of PAHs.

  19. Optimizing catalysis conditions to decrease aromatic hydrocarbons and increase alkanes for improving jet biofuel quality.

    PubMed

    Cheng, Jun; Li, Tao; Huang, Rui; Zhou, Junhu; Cen, Kefa

    2014-04-01

    To produce quality jet biofuel with high amount of alkanes and low amount of aromatic hydrocarbons, two zeolites of HY and HZSM-5 supporting Ni and Mo were used as catalysts to convert soybean oil into jet fuel. Zeolite HY exhibited higher jet range alkane selectivity (40.3%) and lower jet range aromatic hydrocarbon selectivity (23.8%) than zeolite HZSM-5 (13.8% and 58.9%). When reaction temperature increased from 330 to 390°C, yield of jet fuel over Ni-Mo/HY catalyst at 4 MPa hydrogen pressure increased from 0% to 49.1% due to the shift of reaction pathway from oligomerization to cracking reaction. Further increase of reaction temperature from 390 to 410°C resulted in increased yield of jet range aromatic hydrocarbons from 18.7% to 30%, which decreased jet fuel quality. A high yield of jet fuel (48.2%) was obtained at 1 MPa low hydrogen pressure over Ni (8 wt.%)-Mo (12 wt.%)/HY catalyst. PMID:24656484

  20. [Halogenated polycyclic aromatic hydrocarbons in surface sediments of Maozhou River, Shenzhen].

    PubMed

    Sun, Jian-Lin; Ni, Hong-Gang; Ding, Chao; Zeng, Hui

    2012-09-01

    Surface sediments collected from the Maozhou River watershed in Shenzhen were analyzed for the concentration levels and spatial distribution characteristics of halogenated polycyclic aromatic hydrocarbons (HPAHs) using GC-MS. Total concentrations of three chlorinated polycyclic aromatic hydrocarbons (ClPAHs) and six brominated polycyclic aromatic hydrocarbons (BrPAHs) of concern ranged from 3.00 to 301 ng x g(-1) and 7.52 to 285 ng x g(-1), respectively. Source appointments indicated that the HPAHs in these surface sediments were mainly derived from waste incineration, fossil fuel combustion, vehicle emission, and burning of crop straw, accounting for 40%, 20.5% 11.9%, and 11.7% of the total loading, respectively. Additionally, the toxic equivalency quotients (TEQ) of total ClPAHs and BrPAHs ranged from 7.95 to 38.1 pg x g(-1) and 38.1 to 105 pg x g(-1) respectively. Finally, the relationships between the HPAHs levels and different land use types were examined. Results indicated that the levels of HPAHs in surface sediments showed a decreasing trend after the first increase to the peak with the density of industrial land, but inversely proportional to the density of agricultural land. PMID:23243864

  1. The effect of strain rate on polycyclic aromatic hydrocarbon (PAH) formation in acetylene diffusion flames

    SciTech Connect

    Yamamoto, Manabu; Duan, Shici; Senkan, Selim [Department of Chemical Engineering, University of California, Los Angeles, CA 90095 (United States)

    2007-11-15

    Acetylene is a ubiquitous combustion intermediate that is also believed to be the major precursor for aromatic, polycyclic aromatic hydrocarbon (PAH), and soot formation in both hydrocarbon and halogenated hydrocarbon flames. However, in spite of its important role as a flame intermediate, the detailed chemical structures of acetylene diffusion flames have not been studied in the past. Here the detailed chemical structures of counterflow diffusion flames of acetylene at strain rates of 37.7 and 50.3 s{sup -1} are presented. Both flames possessed the same carbon density of 0.37 g/L corresponding to an acetylene mole fraction of 0.375 in argon on the fuel side, and an oxygen mole fraction of 0.22 in argon on the oxidizer side. Concentration profiles of a large number of major, minor, and trace species, including a wide spectrum of aromatics and PAH, have been determined by direct sampling from flames using a heated quartz microprobe coupled to an online gas chromatograph/mass selective detector (GC/MSD). Temperature profiles were made using a thermocouple and the rapid insertion technique. Although the major species concentrations were nearly the same in the two flames, the mole fraction profiles of trace combustion by-products were significantly lower in the higher-strain-rate flame, by nearly two orders of magnitude for PAH. These comparative results provide new information on the trace chemistries of acetylene flames and should be useful for the development and validation of detailed chemical kinetic mechanisms describing the formation of toxic by-products in the combustion of hydrocarbons and halogenated hydrocarbons. (author)

  2. Draft Genome Sequence of Pseudomonas sp. Strain 10-1B, a Polycyclic Aromatic Hydrocarbon Degrader in Contaminated Soil.

    PubMed

    Bello-Akinosho, Maryam; Adeleke, Rasheed; Swanevelder, Dirk; Thantsha, Mapitsi

    2015-01-01

    Pseudomonas sp. strain 10-1B was isolated from artificially polluted soil after selective enrichment. Its draft genome consists of several predicted genes that are involved in the hydroxylation of the aromatic ring, which is the rate-limiting step in the biodegradation of polycyclic aromatic hydrocarbons. PMID:25953172

  3. Formation of polycyclic aromatic hydrocarbons and their growth to soot—a review of chemical reaction pathways

    Microsoft Academic Search

    H. Richter; J. B. Howard

    2000-01-01

    The generation by combustion processes of airborne species of current health concern such as polycyclic aromatic hydrocarbons (PAH) and soot particles necessitates a detailed understanding of chemical reaction pathways responsible for their formation. The present review discusses a general scheme of PAH formation and sequential growth of PAH by reactions with stable and radical species, including single-ring aromatics, other PAH

  4. Aromatic hydrocarbon emissions in the United States deduced from tall tower measurements

    NASA Astrophysics Data System (ADS)

    Hu, L.; Millet, D. B.; Griffis, T. J.; Tessum, C.; Travis, K.

    2013-12-01

    Aromatic compounds including benzene (C6H6), toluene (C7H8), and xylenes (C8H10) are important anthropogenic precursors of secondary organic aerosol and ground-level ozone. In addition, benzene has been classified as a Group 1 carcinogen by the International Agency for Research on Cancer (IARC). However, their emissions remain poorly constrained. Here we present a full year (2011) of continuous aromatic hydrocarbon measurements by PTR-MS at the University of Minnesota tall tower Tracer Gas Observatory (KCMP tall tower, 244 m a.g.l, 44.689°N, 93.073°W). We interpret the tall tower data with a 0.5° ×0.667° GEOS-Chem nested grid simulation to constrain US sources of benzene, toluene, and xylenes. The tall tower observations reveal a clear high bias in the model, with model: measurement slopes of 1.8, 5.3, and 2.9 for benzene, toluene, and xylenes, respectively. The high bias reflects an overestimate of aromatic hydrocarbon emissions in the model, which are based on the RETRO emission Inventory. In this work, we employ a Bayesian inversion to interpret the KCMP tall tower measurements in terms of quantitative constraints on US aromatic sources and the importance of sectors such as on-road transportation, waste treatment and disposal, solvent use, etc. We discuss our findings relative to other emission estimates (e.g., the EPA NEI) and in terms of their implications for air quality modeling.

  5. Polycyclic aromatic hydrocarbon distributions in Mississippi Fan sediments 

    E-print Network

    Sandberg, William Allan

    1986-01-01

    -diode array spectrophotometry (HPLC- DAS) was shown to be incapable of determining quantitative PAH distributions in this chemically complex system under several experimental conditions. TABLE OF CONTENTS Page ABSTRACT, TABLE OF CONTENTS LIST OF TABLES... EXPERIMENTAL PROCEDURE. 17 Sampling procedures Sample preparation, Sample analysis HPLC analysis 17 17 19 29 RESULTS 31 Lower fan site (Site 615) Middle fan site (Site 621). Fan margin (Site 616) Intraslope basins (Sites 618 and 619) General...

  6. A Multiscale Study of Polycyclic Aromatic Hydrocarbon Properties in Galaxies

    E-print Network

    F. Galliano

    2008-02-16

    In the present contribution, I summarize a systematic study of ISO and Spitzer mid-IR spectra of Galactic regions and star forming galaxies. This study quantifies the relative variations of the main aromatic features inside spatially resolved objects as well as among the integrated spectra of 50 objects. Our analysis implies that the properties of the PAHs are remarkably universal throughout our sample and at different spatial scales. In addition, the relative variations of the band ratios, as large as one order of magnitude, are mainly controled by the fraction of ionized PAHs. In particular, I show that we can rule out both the modification of the PAH size distribution and the mid-IR extinction, as an explanation of these variations. High values of the I(6.2)/I(11.3) ratio are found to be associated with the far-UV illuminated surface of PDRs, at the scale of an interstellar cloud, and associated with star formation activity, at the scale of a galaxy. Using a few well-studied Galactic regions, we provide an empirical relation between the I(6.2)/I(11.3) ratio and the ionization/recombination ratio G0/ne. Finally, I show that these trends are consistent with the detailed modeling of the PAH emission within photodissociation regions, taking into account the radiative transfer, the stochastic heating and the charge exchange between gas and dust.

  7. Infrared spectra of protonated polycyclic aromatic hydrocarbon molecules: azulene.

    PubMed

    Zhao, Dawei; Langer, Judith; Oomens, Jos; Dopfer, Otto

    2009-11-14

    The infrared (IR) spectrum of protonated azulene (AzuH(+), C(10)H(9)(+)) has been measured in the fingerprint range (600-1800 cm(-1)) by means of IR multiple photon dissociation (IRMPD) spectroscopy in a Fourier transform ion cyclotron resonance mass spectrometer equipped with an electrospray ionization source using a free electron laser. The potential energy surface of AzuH(+) has been characterized at the B3LYP/6-311G(**) level in order to determine the global and local minima and the corresponding transition states for interconversion. The energies of the local and global minima, the dissociation energies for the lowest-energy fragmentation pathways, and the proton affinity have been evaluated at the CBS-QB3 level. Comparison with calculated linear IR absorption spectra supports the assignment of the IRMPD spectrum to C4-protonated AzuH(+), the most stable of the six distinguishable C-protonated AzuH(+) isomers. Comparison between Azu and C4-AzuH(+) reveals the effects of protonation on the geometry, vibrational properties, and the charge distribution of these fundamental aromatic molecules. Calculations at the MP2 level indicate that this technique is not suitable to predict reliable IR spectra for this type of carbocations even for relatively large basis sets. The IRMPD spectrum of protonated azulene is compared to that of isomeric protonated naphthalene and to an astronomical spectrum of the unidentified IR emission bands. PMID:19916604

  8. Infrared spectra of protonated polycyclic aromatic hydrocarbon molecules: Azulene

    NASA Astrophysics Data System (ADS)

    Zhao, Dawei; Langer, Judith; Oomens, Jos; Dopfer, Otto

    2009-11-01

    The infrared (IR) spectrum of protonated azulene (AzuH+, C10H9+) has been measured in the fingerprint range (600-1800 cm-1) by means of IR multiple photon dissociation (IRMPD) spectroscopy in a Fourier transform ion cyclotron resonance mass spectrometer equipped with an electrospray ionization source using a free electron laser. The potential energy surface of AzuH+ has been characterized at the B3LYP/6-311G?? level in order to determine the global and local minima and the corresponding transition states for interconversion. The energies of the local and global minima, the dissociation energies for the lowest-energy fragmentation pathways, and the proton affinity have been evaluated at the CBS-QB3 level. Comparison with calculated linear IR absorption spectra supports the assignment of the IRMPD spectrum to C4-protonated AzuH+, the most stable of the six distinguishable C-protonated AzuH+ isomers. Comparison between Azu and C4-AzuH+ reveals the effects of protonation on the geometry, vibrational properties, and the charge distribution of these fundamental aromatic molecules. Calculations at the MP2 level indicate that this technique is not suitable to predict reliable IR spectra for this type of carbocations even for relatively large basis sets. The IRMPD spectrum of protonated azulene is compared to that of isomeric protonated naphthalene and to an astronomical spectrum of the unidentified IR emission bands.

  9. Evaluating the Effects of Aromatics Content in Gasoline on Gaseous and Particulate Matter Emissions from SI-PFI and SIDI Vehicles.

    PubMed

    Karavalakis, Georgios; Short, Daniel; Vu, Diep; Russell, Robert; Hajbabaei, Maryam; Asa-Awuku, Akua; Durbin, Thomas D

    2015-06-01

    We assessed the emissions response of a fleet of seven light-duty gasoline vehicles for gasoline fuel aromatic content while operating over the LA92 driving cycle. The test fleet consisted of model year 2012 vehicles equipped with spark-ignition (SI) and either port fuel injection (PFI) or direct injection (DI) technology. Three gasoline fuels were blended to meet a range of total aromatics targets (15%, 25%, and 35% by volume) while holding other fuel properties relatively constant within specified ranges, and a fourth fuel was formulated to meet a 35% by volume total aromatics target but with a higher octane number. Our results showed statistically significant increases in carbon monoxide, nonmethane hydrocarbon, particulate matter (PM) mass, particle number, and black carbon emissions with increasing aromatics content for all seven vehicles tested. Only one vehicle showed a statistically significant increase in total hydrocarbon emissions. The monoaromatic hydrocarbon species that were evaluated showed increases with increasing aromatic content in the fuel. Changes in fuel composition had no statistically significant effect on the emissions of nitrogen oxides (NOx), formaldehyde, or acetaldehyde. A good correlation was also found between the PM index and PM mass and number emissions for all vehicle/fuel combinations with the total aromatics group being a significant contributor to the total PM index followed by naphthalenes and indenes. PMID:25938171

  10. Picosecond 266-nm multiphoton laser photolysis studies on liquid alkane solution of aromatic hydrocarbons: Ultrafast solute triplet formation

    Microsoft Academic Search

    Hiroshi. Miyasaka; Hiroshi. Masuhara; Noboru. Mataga

    1990-01-01

    Triplet formation of aromatic hydrocarbon solute in aliphatic hydrocarbon solution in the picosecond to a few nanosecond time region induced by multiphoton excitation with 266-nm picosecond laser pulse is demonstrated. Mechanisms of the rapid triplet state formation, especially the contribution of the ionized state of solvent molecule to it, are discussed by comparing the results of picosecond laser photolysis studies

  11. Current-voltage characteristics of a homologous series of polycyclic aromatic hydrocarbons.

    PubMed

    Böhme, Thilo; Simpson, Christopher D; Müllen, Klaus; Rabe, Jürgen P

    2007-01-01

    A novel alkyl-substituted polycyclic aromatic hydrocarbon (PAH) with D(2h) symmetry and 78 carbon atoms in the aromatic core (C78) was synthesized, thereby completing a homologous series of soluble PAH compounds with increasing size of the aromatic pi system (42, 60, and 78 carbon atoms). The optical band gaps were determined by UV/Vis and fluorescence spectroscopy in solution. Scanning tunneling microscopy (STM) and spectroscopy (STS) revealed diode-like current versus voltage (I-V) characteristics through individual aromatic cores in monolayers at the interface between the solution and the basal plane of graphite. The asymmetry of the current-voltage (I-V) characteristics increases with the increasing size of the aromatic core, and the concomitantly decreasing HOMO-LUMO gap. This is attributed to resonant tunneling through the HOMO of the adsorbed molecule, and an asymmetric position of the molecular species in the tunnel junction. Consistently, submolecularly resolved STM images at negative substrate bias are in good agreement with the calculated pattern for the electron densities of the HOMOs. The analysis provides the basis for tailoring rectification with a single molecule in an STM junction. PMID:17579898

  12. The phn Island: A New Genomic Island Encoding Catabolism of Polynuclear Aromatic Hydrocarbons

    PubMed Central

    Hickey, William J.; Chen, Shicheng; Zhao, Jiangchao

    2012-01-01

    Bacteria are key in the biodegradation of polycyclic aromatic hydrocarbons (PAH), which are widespread environmental pollutants. At least six genotypes of PAH degraders are distinguishable via phylogenies of the ring-hydroxylating dioxygenase (RHD) that initiates bacterial PAH metabolism. A given RHD genotype can be possessed by a variety of bacterial genera, suggesting horizontal gene transfer (HGT) is an important process for dissemination of PAH-degrading genes. But, mechanisms of HGT for most RHD genotypes are unknown. Here, we report in silico and functional analyses of the phenanthrene-degrading bacterium Delftia sp. Cs1-4, a representative of the phnAFK2 RHD group. The phnAFK2 genotype predominates PAH degrader communities in some soils and sediments, but, until now, their genomic biology has not been explored. In the present study, genes for the entire phenanthrene catabolic pathway were discovered on a novel ca. 232?kb genomic island (GEI), now termed the phn island. This GEI had characteristics of an integrative and conjugative element with a mobilization/stabilization system similar to that of SXT/R391-type GEI. But, it could not be grouped with any known GEI, and was the first member of a new GEI class. The island also carried genes predicted to encode: synthesis of quorum sensing signal molecules, fatty acid/polyhydroxyalkanoate biosynthesis, a type IV secretory system, a PRTRC system, DNA mobilization functions and >50 hypothetical proteins. The 50% G?+?C content of the phn gene cluster differed significantly from the 66.7% G?+?C level of the island as a whole and the strain Cs1-4 chromosome, indicating a divergent phylogenetic origin for the phn genes. Collectively, these studies added new insights into the genetic elements affecting the PAH biodegradation capacity of microbial communities specifically, and the potential vehicles of HGT in general. PMID:22493593

  13. Vertical distribution and potential risk of particulate polycyclic aromatic hydrocarbons in high buildings of Bangkok, Thailand.

    PubMed

    Pongpiachan, Siwatt

    2013-01-01

    Vertical variations of polycyclic aromatic hydrocarbon (PAH) concentrations in PM10 were investigated in order to assess the factors controlling their behavior in the urban atmosphere of Bangkok City, Thailand. Air samples were collected every three hours for three days at three different levels at Bai-Yok Suit Hotel (site-1 and site-2) and Bai-Yok Sky Hotel (site-3) in February 18th-21st, 2008. The B[a]P concentration showed a value 0.54 fold, lower than the United Kingdom Expert Panel on Air Quality Standard (UK-EPAQS; i.e. 250 pg m-3) at the top level. In contrast, the B[a]P concentrations exhibited, at the ground and middle level, values 1.50 and 1.43 times higher than the UK-EPAQS standard respectively. PAHs displayed a diurnal variation with maximums at night time because of the traffic rush hour coupled with lower nocturnal mixing layer, and the decreased wind speed, which consequently stabilized nocturnal boundary layer and thus enhanced the PAH contents around midnight. By applying Nielsen's technique, the estimated traffic contributions at Site-3 were higher than those of Site-1: about 10% and 22% for Method 1 and Method 2 respectively. These results reflect the more complicated emission sources of PAHs at ground level in comparison with those of higher altitudes. The average values of incremental individual lifetime cancer risk (ILCR) for all sampling sites fell within the range of 10?7-10?6, being close to the acceptable risk level (10?6) but much lower than the priority risk level (10?4). PMID:23679287

  14. Determination of polycyclic aromatic hydrocarbons in alcoholic drinks and the identification of their potential sources.

    PubMed

    García-Falcón, M S; Simal-Gándara, J

    2005-09-01

    Some polycyclic aromatic hydrocarbons (PAHs), particularly those with a high molecular mass, have been classified as probably being carcinogenic to humans by the International Agency for Research on Cancer (IARC). The significance of the determination of PAHs is reflected by the special attention the European Union is paying to regulating their maximum allowed levels in various types of foodstuffs. Like tobacco and smoked meats, alcoholic drinks can also contain these carcinogenic chemicals, as the latter have been detected in the charred insides of barrels, some ingredients such as caramel or the smoke released during the drying of germinated barley in beer or whisky. This paper determined the contents of seven PAHs in alcoholic beverages of variable alcoholic strength that had been aged in charred barrels for different times (months, years). The aim was to elucidate the dependence of the formation of seven PAHs on the type of charring (traditional or convective) used and the charring intensity (light, medium or heavy). Based on the results, the way the tree raw material is toasted strongly influences PAH levels in alcoholic drinks; thus, traditional charring produces increased amounts of PAHs from the wood relative to convective toasting. The sum of the analysed PAH concentrations in the aged alcoholic beverages studied ranged from zero for a white wine to 172 ng l(-1) for a 'brandy de jerez solera'. The carcinogenic indicator benzo[a]pyrene was found at concentrations below 10 ng l(-1). These PAH concentrations in alcoholic beverages are very low relative to those in smoked and char-broiled foodstuffs. Any health hazards, however, can be minimized by using convective toasting to manufacture the barrels where the drinks are to be aged. PMID:16192065

  15. Residual indoor contamination from world trade center rubble fires as indicated by polycyclic aromatic hydrocarbon profiles.

    PubMed

    Pleil, Joachim D; Funk, William E; Rappaport, Stephen M

    2006-02-15

    The catastrophic destruction of the World Trade Center (WTC) on Sept. 11, 2001 (9/11) created an immense dust cloud followed by fires that emitted smoke and soot into the air of New York City (NYC) well into December. Outdoor pollutant levels in lower Manhattan returned to urban background levels after about 200 days as the fires were put out and the debris cleanup was completed. However, particulate matter (PM) from the original collapse and fires also penetrated into commercial and residential buildings. This has created public concern because WTC dust is thought to cause adverse pulmonary symptoms including "WTC cough" and reduced lung capacity. Additionally, some recent studies have suggested a possible link between exposure to WTC contamination and other adverse health effects. Distinguishing between normal urban pollutant infiltration and residual WTC dust remaining in interior spaces is difficult; efforts are underway to develop such discriminator methods. Some progress has been made in identifying WTC dust by the content of fibers believed to be associated with the initial building collapse. There are also contaminants created by the fires that burned for 100 days in the debris piles of the building rubble. Using WTC ambient air samples, we have developed indicators for fire related PM based on the relative amounts of specific particle bound polycyclic aromatic hydrocarbons (PAHs) and the mass fraction of PAHs per mass of PM. These two parameters are combined, and we show a graphical method for discriminating between fire sources and urban particulate sources as applied to samples of settled dusts. We found that our PAHs based discriminator method can distinguish fire source contributions to WTC related particulate matter and dusts. Other major building fires or large open burn events could have similar PAHs characteristics. We found that random samples collected approximately 3.5 years after the WTC event from occupied indoor spaces (primarily residential) in the New York area are not statistically distinguishable from contemporary city background. PMID:16572771

  16. Comparative Genomics Reveals Adaptation by Alteromonas sp. SN2 to Marine Tidal-Flat Conditions: Cold Tolerance and Aromatic Hydrocarbon Metabolism

    PubMed Central

    Math, Renukaradhya K.; Jin, Hyun Mi; Kim, Jeong Myeong; Hahn, Yoonsoo; Park, Woojun; Madsen, Eugene L.; Jeon, Che Ok

    2012-01-01

    Alteromonas species are globally distributed copiotrophic bacteria in marine habitats. Among these, sea-tidal flats are distinctive: undergoing seasonal temperature and oxygen-tension changes, plus periodic exposure to petroleum hydrocarbons. Strain SN2 of the genus Alteromonas was isolated from hydrocarbon-contaminated sea-tidal flat sediment and has been shown to metabolize aromatic hydrocarbons there. Strain SN2's genomic features were analyzed bioinformatically and compared to those of Alteromonas macleodii ecotypes: AltDE and ATCC 27126. Strain SN2's genome differs from that of the other two strains in: size, average nucleotide identity value, tRNA genes, noncoding RNAs, dioxygenase gene content, signal transduction genes, and the degree to which genes collected during the Global Ocean Sampling project are represented. Patterns in genetic characteristics (e.g., GC content, GC skew, Karlin signature, CRISPR gene homology) indicate that strain SN2's genome architecture has been altered via horizontal gene transfer (HGT). Experiments proved that strain SN2 was far more cold tolerant, especially at 5°C, than the other two strains. Consistent with the HGT hypothesis, a total of 15 genomic islands in strain SN2 likely confer ecological fitness traits (especially membrane transport, aromatic hydrocarbon metabolism, and fatty acid biosynthesis) specific to the adaptation of strain SN2 to its seasonally cold sea-tidal flat habitat. PMID:22563400

  17. Source apportionment of polycyclic aromatic hydrocarbons in soils of wetlands in the Liao River Delta, Northeast China.

    PubMed

    Ma, Chuanliang; Ye, Siyuan; Lin, Tian; Ding, Xigui; Yuan, Hongming; Guo, Zhigang

    2014-03-15

    The polycyclic aromatic hydrocarbons (PAHs) of 55 surface soil samples from the wetlands in the Liao River Delta, Northeast China were measured in order to apportion their sources. The total concentrations of 16 US EPA priority PAHs and alkyl-PAHs in this region ranged 106-3148 ng g?¹ (dry weight) (average: 550 ± 565 ng g?¹) and 54-5564 ng g?¹ (average: 517 ± 838 ng g?¹), respectively. Based on the positive matrix factorization analysis of alkylated and parent PAHs, six sources of PAHs were identified including petroleum (23%), biomass burning (23%), air-soil exchange (18%), coal combustion (17%), traffic emission (14%) and biogenic origin (6%). The positive correlation between low molecular weight (LMW) PAHs and TOC contents could demonstrate a potential positive influence of TOC on the accumulations of LMW PAHs in soils by the air-soil exchange. The petrogenic PAHs may pose a limited harmful effect on aquatic organisms although they were abundant in the area. PMID:24461691

  18. Sediment-porewater partitioning of polynuclear aromatic hydrocarbons (PAHs)

    SciTech Connect

    Maruya, K.A.; Risebrough, R.W.; Horne, A.J. [Univ. of California, Berkeley, CA (United States)

    1996-10-01

    Quantifying the distribution of hydrophobic organic compounds between contaminated sediment and interstitial water is key to understanding their fate and effects in aquatic ecosystems. Sampling during the wet and dry-seasons in San Francisco Bay has revealed that the extent of partitioning, measured as the apparent sediment organic carbon-porewater distribution coefficient (K{sub oc}{prime}), was positively correlated with the octanol-water distribution coefficient (K{sub ow}) for a suite of pyrogenically-derived, 2-6 ring PAHs. In addition, sediment PAHs (organic carbon basis) were associated with the silt fraction and organic carbon content. Moreover, K{sub oc}{prime} decreased along an intertidal gradient and was an order of magnitude higher during the wet season when runoff into the Bay was high. Our results provide evidence that substrate heterogeneity, a factor not accounted for in simple equilibrium models, can significantly alter the distribution of PAHs in this environment.

  19. Spatial and temporal distributions of polycyclic aromatic hydrocarbons in sediments from the Songhua River, China

    NASA Astrophysics Data System (ADS)

    Dong, D.; Guo, Z.; Liu, X.; Hua, X.; Liang, D.

    2013-12-01

    Polycyclic aromatic hydrocarbons (PAHs), a class of typical persistent organic pollutants, widely exist in the environment and are potentially harmful to human health. They can enter the waters through atmospheric deposition, soil leaching, shipping, sewage discharges and surface runoff. In recent years, many studies on the distributions of PAHs in major rivers, lakes and bays around the world have been carried out. In this study, 9 surface sediments (0-10cm) were sampled from the Songhua River in Jilin and Heilongjiang provinces. The contents of 16 PAHs in the US Environmental Protection Agency list of priority pollutants were determined and their spatial distributions were discussed. Sediment cores (50cm length) in three oxbow lakes in this area were also collected and cut into 2 cm thickness sub-samples. PAHs concentrations in these samples were determined and the cores were dated using a 210Pb geochronology technique. Finally, the sedimentary history of PAHs in the Songhua River since the 1920s was revealed. Results indicated that total concentration of the 16 PAHs analyzed in the surface sediments was 187-2079 ng/g (dry weight), and the mean was 1029 ng/g. Sediments collected from near urban areas (Jilin and Harbin City) contained higher PAHs content. Compared with the domestic and international rivers, the PAHs content in this river sediments is at a medium level. The PAHs profiles showed that 2-3 ring PAHs, especially naphthalene, were dominant in all of the samples. Sedimentary flux can reflect the accumulating history of pollutants better. The PAHs fluxes were low and varied little from the 1920s to 1970s, but higher PAH fluxes were found since the 1980s in each core (Fig. 1). The PAHs sedimentary flux near Harbin City (Shuangcheng) was found changed remarkably. We inferred that the PAHs might be influenced by hydrological conditions, population mobility and economic activity in this area. PAHs sedimentary record in the Songhua River revealed that the economic development in large cities in this area lagged behind the environmental protection. Acknowledgments: This work was supported by Specialized Research Fund for the Doctoral Program of Higher Education (No. 20100061110041), and the Major Science and Technology Program for Water Pollution Control and Treatment, China (No. 2009ZX0707-001-03). Fig. 1 PAHs fluxes vs. year in sediment cores from Songyuan, Shuangcheng (Harbin) and Mulan

  20. Docosahexaenoic acid regulates gene expression in HUVEC cells treated with polycyclic aromatic hydrocarbons.

    PubMed

    Gdula-Argasi?ska, Joanna; Czepiel, Jacek; Toto?-?ura?ska, Justyna; Jurczyszyn, Artur; Perucki, William; Wo?kow, Pawe?

    2015-07-16

    The molecular mechanism of inflammation and carcinogenesis induced by exposure of polycyclic aromatic hydrocarbons (PAHs) is not clearly understood. Our study was undertaken due to the strong pro-carcinogenic potential and reactivity of PAH-metabolites, as well as the susceptibility of polyunsaturated fatty acids to oxidation. The aim of this study was to evaluate the pro- or anti-inflammatory impact of n-3 docosahexaenoic acid on human primary umbilical vein endothelial cells (HUVEC) exposed to polycyclic aromatic hydrocarbons. We analysed the influence of docosahexaenoic acid (DHA) and/or PAHs supplementation on the fatty acid profile of cell membranes, on cyclooxygenase-2 (COX-2), aryl hydrocarbon receptor (AHR), and glutathione S transferase Mu1 (GSTM1) protein expression as well as on the prostaglandin synthase 2 (PTGS2), AHR, GSTM1, PLA2G4A, and cytochrome P450 CYP1A1 gene expression. We observed that COX-2 and AHR protein expression was increased while GSTM1 expression was decreased in cells exposed to DHA and PAHs. Docosahexaenoic acid down-regulated CYP1A1 and up-regulated the AHR and PTGS2 genes. Our findings suggested that DHA contributes significantly to alleviate the harmful effects caused by PAHs in endothelial cells. Moreover, these results suggest that a diet rich in n-3 fatty acids is helpful to reduce the harmful effects of PAHs exposure on human living in heavily polluted areas. PMID:25956473

  1. The cytosolic receptor binding affinities and AHH induction potencies of 29 polynuclear aromatic hydrocarbons.

    PubMed

    Piskorska-Pliszczynska, J; Keys, B; Safe, S; Newman, M S

    1986-11-01

    The dose-response rat hepatic cytosolic receptor-binding avidities, aryl hydrocarbon hydroxylase (AHH) and ethoxyresorufin O-deethylase (EROD) induction potencies in rat hepatoma H-4-II E cells in culture were determined for 29 polynuclear aromatic hydrocarbons. It was apparent that the magnitude of the EC50 values for these in vitro responses were strongly dependent on structure. Dibenz[a,h]anthracene (1.6 X 10(-8) M), 7-methylbenz[a]anthracene (1.6 X 10(-8) M), 3-methylcholanthrene (2.8 X 10(-8) M) and picene (4.5 X 10(-8) m) exhibited the highest affinity for the receptor protein and these compounds were only 5-fold less active the 2,3,7,8-tetrachlorodibenzo-p-dioxin (1 X 10(-8) M). All of the compounds which were active in the receptor-binding and monooxygenase enzyme-induction assays possessed one common structural feature, namely the presence of a phenanthrene structure fused with at least 1 benzo ring. The results also demonstrated that there was not any apparent correlation between the receptor-binding avidities and in vitro monooxygenase enzyme-induction potencies for the most active polynuclear aromatic hydrocarbons. PMID:3024361

  2. Reaction dynamics in astrochemistry: low-temperature pathways to polycyclic aromatic hydrocarbons in the interstellar medium.

    PubMed

    Kaiser, Ralf I; Parker, Dorian S N; Mebel, Alexander M

    2015-04-01

    Bimolecular reactions of phenyl-type radicals with the C4 and C5 hydrocarbons vinylacetylene and (methyl-substituted) 1,3-butadiene have been found to synthesize polycyclic aromatic hydrocarbons (PAHs) with naphthalene and 1,4-dihydronaphthalene cores in exoergic and entrance barrierless reactions under single-collision conditions. The reaction mechanism involves the initial formation of a van der Waals complex and addition of a phenyl-type radical to the C1 position of a vinyl-type group through a submerged barrier. Investigations suggest that in the hydrocarbon reactant, the vinyl-type group must be in conjugation with a -C?CH or -HC=CH2 group to form a resonantly stabilized free radical intermediate, which eventually isomerizes to a cyclic intermediate followed by hydrogen loss and aromatization (PAH formation). The vinylacetylene-mediated formation of PAHs might be expanded to more complex PAHs, such as anthracene and phenanthrene, in cold molecular clouds via barrierless reactions involving phenyl-type radicals, such as naphthyl, which cannot be accounted for by the classical hydrogen abstraction-acetylene addition mechanism. PMID:25422849

  3. Reflectance spectroscopy (350-2500 nm) of solid-state polycyclic aromatic hydrocarbons (PAHs)

    NASA Astrophysics Data System (ADS)

    Izawa, M. R. M.; Applin, D. M.; Norman, L.; Cloutis, E. A.

    2014-07-01

    Polycyclic aromatic hydrocarbons (PAHs) are organic compounds based on fused aromatic rings, and are formed in a variety of astrophysical, solar nebula and planetary processes. Polycyclic aromatic hydrocarbons are known or suspected to occur in a wide variety of planetary settings including icy satellites, Titan’s hazes, carbonaceous meteorites, comet nuclei, ring particles; and terrestrial organic-rich lithologies such as coals, asphaltites, and bituminous sands. Relatively few measurements of the visible and near-infrared spectra of PAHs exist, yet this wavelength region (350-2500 nm) is widely used for remote sensing. This study presents detailed analyses of the 350-2500 nm reflectance spectra of 47 fine-grained powders of different high-purity solid-state PAHs. Spectral properties of PAHs change with variations in the number and connectivity of linked aromatic rings and the presence and type of side-groups and heterocycles. PAH spectra are characterized by three strong features near ?880 nm, ?1145 nm, and ?1687 nm due to overtones of ?CH fundamental stretching vibrations. Some PAHs are amenable to remote detection due to the presence of diagnostic spectral features, including: Nsbnd H stretching overtones at 1490-1515 nm in NH- and NH2-bearing PAHs, aliphatic or saturated bond Csbnd H overtone vibrations at ?1180-1280 nm and ?1700-1860 nm; a broad asymmetric feature between ?1450 nm and ?1900 nm due to Osbnd H stretching overtones in aromatic alcohols, Csbnd H and Cdbnd O combinations near ?2000-2010 nm and ?2060-2270 nm in acetyl and carboxyl-bearing PAHs. Other substituents such as sulphonyl, thioether ether and carboxyl heterocycles, or cyano, nitrate, and aromatic side groups, do not produce well-resolved diagnostic spectral features but do cause shifts in the positions of the aromatic Csbnd H vibrational overtone features. Fluorescence is commonly suppressed by the presence of heterocycles, side-groups and in many non-alternant PAHs. The spectral characteristics of PAHs offer the potential, under suitable circumstances, for remote characterization of the classes of PAH present and in some cases, identification of particular heterocyclic or side-group substituents.

  4. Desorption resistance of polycyclic aromatic hydrocarbons and duration of exposure.

    PubMed

    Chai, Yunzhou; Kochetkov, Alexander; Reible, Danny D

    2006-11-01

    The desorption-resistant fraction of laboratory-spiked phenanthrene in two Louisiana (USA) sediments was not observed to be significantly different, but the two sediments exhibited different condensed-phase organic carbon contents, as defined operationally by the organic carbon remaining after combustion of the sediment at 375 degrees C. Only 3% of the original saturated phenanthrene in the sediments was not readily removed by exposure to a nonpolar polymeric resin and sorbent XAD-2. Allowing the laboratory-spiked contaminants to age for periods of up to three years yielded little difference in the desorption-resistant characteristics of the sediments. Field-contaminated sediments from Utica Harbor (Utica, NY, U.S.A.) and Rouge River (Detroit, MI, USA) that had a lengthy (decades to a century) period of contamination, however, exhibited significantly different desorption-resistant contaminant fractions, consistent with the fractions of condensed-phase organic carbon in the sediments. Measurements of the fraction that could be rapidly desorbed using the XAD-2 sorbent also accounted for essentially all desorption to pore water and, thus, provided a good prediction of effective bulk partition coefficients. It was concluded that the condensed-phase organic carbon was a good indicator of the potential for desorption resistance in field-contaminated sediments and that the rapidly desorbing fraction provided a quantitative indicator of its significance. PMID:17089703

  5. A Theoretical Study on the Vibrational Spectra of Polycyclic Aromatic Hydrocarbon Molecules with Aliphatic Sidegroups

    NASA Astrophysics Data System (ADS)

    Sadjadi, SeyedAbdolreza; Zhang, Yong; Kwok, Sun

    2015-03-01

    The role of aliphatic side groups in the formation of astronomical unidentified infrared emission (UIE) features is investigated by applying the density functional theory to a series of molecules with mixed aliphatic-aromatic structures. The effects of introducing various aliphatic groups to a fixed polycyclic aromatic hydrocarbon (PAH) core (ovalene) are studied. Simulated spectra for each molecule are produced by applying a Drude profile at T = 500 K while the molecule is kept at its electronic ground state. The vibrational normal modes are classified using a semi-quantitative method. This allows us to separate the aromatic and aliphatic vibrations, and therefore provides clues to what types of vibrations are responsible for the emissions bands at different wavelengths. We find that many of the UIE bands are not pure aromatic vibrational bands but may represent coupled vibrational modes. The effects of aliphatic groups on the formation of the 8 ?m plateau are quantitatively determined. The vibrational motions of methyl (-CH3) and methylene (-CH2 -) groups can cause the merging of the vibrational bands of the parent PAH and the forming of broad features. These results suggest that aliphatic structures can play an important role in the UIE phenomenon.

  6. ORIGIN OF ORGANIC GLOBULES IN METEORITES: LABORATORY SIMULATION USING AROMATIC HYDROCARBONS

    SciTech Connect

    Saito, Midori [Institute for Molecular Science, National Institutes of Natural Sciences, Okazaki, Aichi 444-8585 (Japan); Kimura, Yuki [Department of Earth and Planetary Materials Science, Graduate School of Science, Tohoku University, Sendai 980-8578 (Japan)

    2009-10-01

    Analogs of organic hollow globules, which have been found in carbonaceous chondrite meteorites and interplanetary dust particles, were synthesized in our laboratory from benzene and anthracene using plasma. Our results suggest that organic globules could be made from aromatic rings in circumstellar envelopes around evolved stars. The hollow interior could be formed by coagulation of vacancies, formed by electronic excitation and/or knock-out of carbon atoms following irradiation by plasma particles such as protons and He{sup +} ions. This experimental result suggests that organic globules are possibly the final products in the evolution of carbonaceous matter from acetylene and benzene to polycyclic aromatic hydrocarbons in ejecta gas from evolved stars.

  7. Polycyclic aromatic hydrocarbon composition in soils and sediments of high altitude lakes.

    PubMed

    Grimalt, Joan O; van Drooge, Barend L; Ribes, Alejandra; Fernández, Pilar; Appleby, Peter

    2004-09-01

    Polycyclic aromatic hydrocarbons (PAH) in lake sediments and nearby soils of two European high mountain regions, Pyrenees and Tatra, have been studied. Similar mixtures of parent PAH were observed in all cases, indicating predominance of airborne transported combustion products. Nevertheless, the composition of these atmospherically long-range transported PAH was better preserved in the superficial layers of soils than sediments. This difference points to significant PAH degradation process, e.g. during lake water column transport, before accumulation in the latter. Post-depositional transformation was also different in both types of environmental compartments. Thus, lake sediments exhibit higher preservation of the more labile PAH involving lower degree of post-depositional oxidation. However, they also show the formation of major amounts of perylene by diagenetic transformation in the deep sections. This compound is not formed in soils where downcore enrichments of phenanthrene are observed, probably as a consequence of diagenetic aromatization of diterpenoids. PMID:15210271

  8. Boron-Containing Polycyclic Aromatic Hydrocarbons: Facile Synthesis of Stable, Redox-Active Luminophores.

    PubMed

    Hertz, Valentin M; Bolte, Michael; Lerner, Hans-Wolfram; Wagner, Matthias

    2015-07-20

    Herein we show that replacing the two meso carbon atoms of the polycyclic aromatic hydrocarbon (PAH) bisanthene by boron atoms transforms a near-infrared dye into an efficient blue luminophore. This observation impressively illustrates the impact of boron doping on the frontier orbitals of PAHs. To take full advantage of this tool for the targeted design of organic electronic materials, the underlying structure-property relationships need to be further elucidated. We therefore developed a modular synthesis sequence based on a Peterson olefination, a stilbene-type photocyclization, and an Si-B exchange reaction to substantially broaden the palette of accessible polycyclic aromatic organoboranes and to permit a direct comparison with their PAH congeners. PMID:26060003

  9. Hydrocarbon content of geopressured brines. Final report

    SciTech Connect

    Osif, T.L.

    1985-08-01

    Design Well data (bottomhole pressure minus wellhead pressure, GWR, and hydrocarbon composition) is presented as a function of producing conditions. These are examined in conjunction with the following models to attempt to deduce the reservoir brine saturation level: (1) reservoir contains gas dispersed in the pores and the gas saturation is greater than critical; (2) reservoir brine is gas-saturated; (3) bubble point below hydrostatic pressure; and (4) bubble point between hydrostatic pressure and reservoir pressure. 24 figs., 10 tabs. (ACR)

  10. POLYCYCLIC AROMATIC HYDROCARBON EXPOSURE AND BURDEN OF OUTDOOR WORKERS IN BUDAPEST

    Microsoft Academic Search

    Judit Szaniszló; György Ungváry

    2001-01-01

    Polycyclic aromatic hydrocarbons exposure (PAHs: (benz[a]anthracene, benzo[a]pyrene, dibenz[a,h]anthracene, benzo[b]fluoranthene, benzo[k]fluoranthene, indeno[1,2,3-cd]-pyrene, fluoranthene, chrysene, pyrene) of policemen on street duty in downtown Budapest and workers repairing the road (asphalting) at a traffic junction and their excretion of PAH metabolites (1-hydroxypyrene, 3-hydroxybenz[a]anthracene, and 3-hydroxybenzo[a]pyrene) were determined. As controls, health-care workers were investigated. In addition PAH pollution of the air of a factory

  11. Computerized gas chromatographic-mass spectrometric analysis of polycyclic aromatic hydrocarbons in environmental samples.

    PubMed

    Lao, R C; Thomas, R S; Monkman, J L

    1975-10-29

    Substantial progress has been made in the last few years in the development of a rapid method for determining polycyclic aromatic hydrocarbons (PAH) in environmental samples. The three-step method consists of (i) a preliminary separation of PAH by solvent and/or column chromatography, (ii) identification by a combination of gas chromatography with quadrupole mass spectrometry and computer, and (iii) measurement by computerized gas chromatography using internal standards. Samples of industrial effluents, coke oven emissions, coal tar and airborne particulates have been investigated. The efficiencies of different gas chromatographic columns were evaluated during these investigations. PMID:1184696

  12. Pyrosequence analysis of bacterial communities in aerobic bioreactors treating polycyclic aromatic hydrocarbon-contaminated soil

    Microsoft Academic Search

    David R. Singleton; Stephen D. Richardson; Michael D. Aitken

    Two aerobic, lab-scale, slurry-phase bioreactors were used to examine the biodegradation of polycyclic aromatic hydrocarbons\\u000a (PAHs) in contaminated soil and the associated bacterial communities. The two bioreactors were operated under semi-continuous\\u000a (draw-and-fill) conditions at a residence time of 35 days, but one was fed weekly and the other monthly. Most of the quantified\\u000a PAHs, including high-molecular-weight compounds, were removed to a

  13. Peculiar effects of alkali thiocyanates on the activity coefficients of aromatic hydrocarbons in water

    Microsoft Academic Search

    Masanobu Janado; Yuki Yano; Yukio Doi; Hiroko Sakamoto

    1983-01-01

    Among twenty-two 1:1 electrolytes examined, LiSCN, CsSCN, KSCN and CsI have a considerable effect on the aqueous solubilities of a series of nonelectrolytes. LiSCN shows a salting-in effect for all the nonelectrolytes examined including 1-octanol, benzene, naphthalene and biphenyl while CsSCN and CsI show a salting-out effect for 1-octanol but a salting-in effect for all the aromatic hydrocarbons. The effect

  14. Evidence that Polycyclic Aromatic Hydrocarbons in Two Carbonaceous Chondrites Predate Parent-Body Formation

    NASA Technical Reports Server (NTRS)

    Plows, F. L.; Elsila, J. E.; Zare, R. N.; Buseck, P. R.

    2003-01-01

    Organic material in meteorites provides insight into the cosmochemistry of the early solar system. The distribution of polycyclic aromatic hydrocarbons (PAHs) in the Allende and Murchison carbonaceous chondrites was investigated using spatially resolved microprobe laser-desorption laser-ionization mass spectrometry. Sharp chemical gradients of PAHs are associated with specific meteorite features. The ratios of various PAH intensities relative to the smallest PAH, naphthalene, are nearly constant across the sample. These findings suggest a common origin for PAHs dating prior to or contemporary with the formation of the parent body, consistent with proposed interstellar formation mechanisms.

  15. Distribution and sources of polycyclic aromatic hydrocarbons in the surface sediments of Gorgan Bay, Caspian Sea.

    PubMed

    Araghi, Peyman Eghtesadi; Bastami, Kazem Darvish; Rahmanpoor, Shirin

    2014-12-15

    The level and source of 16 polycyclic aromatic hydrocarbons (PAHs) were investigated in the surface sediments from the Gorgan Bay, Caspian Sea. The sum of 16 PAHs (?PAH16) concentrations varied from 107.87 to 516.18 ng g(-1)dry weight, with average value of 270.96 ± 150.47 ng g(-1)dry weight. Ecological risk assessment of PAHs, indicated that adverse biological effects caused by acenaphthene, naphthalene, fluoranthene and Pyrene occasionally and frequently may take place in the sediments of Gorgan Bay. PAHs source identification demonstrated that the PAHs come from mixed and pyrogenic origin. PMID:24661458

  16. Characterization and source apportionment of polycyclic aromatic hydrocarbons (PAHs) in Sediments from the Bohai Sea, China

    NASA Astrophysics Data System (ADS)

    Liu, Jihua; Hu, Ningjing; Shi, Xuefa

    2015-04-01

    Characterization and source apportionment of polycyclic aromatic hydrocarbons (PAHs) in Sediments from the Bohai Sea, China Liu Jihua, Hu Ningjing, Shi Xuefa First Institute of Oceanography, State Oceanic Administration, Qingdao 266061, China Polycyclic aromatic hydrocarbons (PAHs) are a class of ubiquitous organic contaminants in the environment. Indeed, 16 PAH compounds have been listed as priority pollutants by the United States Environmental Protection Agency and the European Union because of their potential toxicity to humans and ecosystems. As POPs are released or escape into the environment, their global accumulation in marine sediments generates a complex balance between inputs and outputs. Furthermore, PAHs in coastal sediments can serve as effective tracers of materials transport from land-to-sea (Fang et al., 2009). Hence, investigations of PAHs in sediments can provide useful information for further understanding of environmental processes and material transport. In this study, sixteen polycyclic aromatic hydrocarbons (PAHs) were extracted from a total of 112 surface sediment samples collected across the entire territory of the Bohai Sea. The detectable concentrations of PAHs ranged from 97.2 to 300.7 ng/g across all samples, indicating low contamination levels of PAHs compared with reported values for other coastal sediments in China and developed countries. The highest concentrations were found within three belts in the vicinity of Luan River Estuary-Qinhuangdao Harbor, the Cao River Estuary-Bohai Sea Center, and north of the Yellow River Estuary. The distribution patterns of PAHs and source identification implied that PAH contamination in the Bohai Sea mainly originates from offshore oil exploration, sewage discharge from rivers and shipping activities. Further Principal components analysis (PCA)/multivariate linear regression (MLR) analysis suggested that the contributions of spilled oil products (petrogenic), coal combustion and traffic-related pollution were 39, 38 and 23%, respectively. Pyrogenic sources (coal combustion and traffic-related pollution) contributed 61% of anthropogenic PAHs to sediments, which indicates that energy consumption is a predominant factor in PAH pollution in the Bohai Sea. Acknowledgements: This work was jointly supported by National Science Fund, China (Grant No.40806025), the State Oceanic Administration, China (Grant No. 201105003, 908-02-02-05, and GY02-2009G19). References Fang MD, Chang WK, Lee CL, Liu JT (2009) The use of polycyclic aromatic hydrocarbons as a particulate tracer in the water column Kaoping submarine canyon. J Mar Syst 76: 457-467.

  17. Detection of Medium-Sized Polycyclic Aromatic Hydrocarbons via Fluorescence Energy Transfer

    PubMed Central

    Serio, Nicole; Prignano, Lindsey; Peters, Sean; Levine, Mindy

    2015-01-01

    Reported herein is the use of proximity-induced non-covalent energy transfer for the detection of medium-sized polycyclic aromatic hydrocarbons (PAHs). This energy transfer occurs within the cavity of ?-cyclodextrin in various aqueous environments, including human plasma and coconut water. Highly efficient energy transfer was observed, and the efficiency of the energy transfer is independent of the concentration of ?-cyclodextrin used, demonstrating the importance of hydrophobic binding in facilitating such energy transfer. Low limits of detection were also observed for many of the PAHs investigated, which is promising for the development of fluorescence-based detection schemes. PMID:25821390

  18. Polycyclic aromatic hydrocarbons in surface sediments of Laizhou Bay, Bohai Sea, China

    Microsoft Academic Search

    Ning Jing Hu; Xue Fa Shi; Peng Huang; Ji Hua Liu

    2011-01-01

    Concentration, distribution, and sources of 16 polycyclic aromatic hydrocarbons (PAHs) were investigated in surface sediments\\u000a of Laizhou Bay, China. Total PAH concentrations ranged from 97.2 to 204.8 ng\\/g, with a mean of 148.4 ng\\/g. High concentrations\\u000a of PAHs were found in the fine-grained sediments on both sides of the Yellow River estuary (YRE). In contrast, low levels\\u000a of PAHs were observed in

  19. [Profile of polycyclic aromatic hydrocarbons in the waters of the Estonian SSR].

    PubMed

    Veldre, I A; Itra, A R; Wettig, K

    1987-01-01

    The profiles of various polynuclear aromatic hydrocarbons (PAH) in water and bottom sediments of some rivers of the Estonian SSR and bays of the Baltic Sea, as well as algae gathered from the latter waterbody, have been studied. These data were compared with profiles in oil-shale emissions, sewage and automobile exhaust gases. No distinct differences of the emission profiles could be detected and therefore it seems to be impossible to fix the main source of the PAH pollution of the waterbodies. PMID:2446589

  20. Bioremediation of polycyclic aromatic hydrocarbons contaminated soil with Monilinia sp.: degradation and microbial community analysis

    Microsoft Academic Search

    Yucheng Wu; Yongming Luo; Dexun Zou; Jinzhi Ni; Wuxin Liu; Ying Teng; Zhengao Li

    2008-01-01

    Microcosms were set up with a PAHs-contaminated soil using biostimulation (addition of ground corn cob) and bioaugmentation\\u000a (inoculated with Monilinia sp. W5-2). Degradation of polycyclic aromatic hydrocarbons and microbial community were examined at the end of incubation\\u000a period. After 30 days, bioaugmented microcosms showed a 35 ± 0% decrease in total PAHs, while biostimulated and control microcosms\\u000a showed 16 ± 9% and 3 ± 0% decrease in

  1. Coating Polycyclic Aromatic Hydrocarbon Cations with Helium Clusters: Snowballs and Slush.

    PubMed

    Calvo, Florent

    2015-06-11

    The classical and quantum structures of cationic polycyclic aromatic hydrocarbon molecules (benzene, pyrene, coronene, and circumcoronene) coated by helium atoms have been theoretically investigated using a variety of computational methods. Classical shell filling, as determined from global optimization, is generally found to proceed by epitaxial additions on the graphitic surfaces before peripheral closure. From the quantum mechanical perspective provided by path-integral molecular dynamics simulations, vibrational delocalization is found to generally decrease the size of this first solvation shell, but also to give rise to a variety of situations in which the helium atoms are more or less localized depending on their environment, with strong finite size effects depending both on the hydrocarbon cation and the number of coating helium atoms. While the graphitic planes tend to bind helium sufficiently to give rise to snowball precursors, the peripheral regions are less dense and more delocalized, not as liquid as the outer layers but within an intermediate slushy character. PMID:25482143

  2. Effect of petroleum aromatic hydrocarbons on monogeneids parasitizing Atlantic cod, Gadus morhua L

    SciTech Connect

    Khan, R.A.; Kiceniuk, J.W.

    1988-07-01

    Fish gills appear to be more susceptible than other tissues to toxicants. The latter include petroleum aromatic hydrocarbons, which can induce lesions characterized by excessive mucus secretion, hyperplasia, fusion of secondary gill lamellae and capillary dilation. Fish are also natural hosts to several species of ectoparasites, especially monogeneans which live among the gill filaments. A previous study on the interrelation of water quality, gill parasites and gill pathology provided evidence that fish living in habitats degraded by pollutants such as Biscayne Bay, Florida, were heavily infested with monogeneids especially when gill lesions were severe. Atlantic cod, Gadus morhua, are hosts to monogeneans. The authors reported previously that crude oil fractions induced gill lesions in cod and also affected some gastrointestinal parasites. In the light of these reports, a study was undertaken to ascertain whether any relationship existed between gill lesions and gill parasites in cod following chronic exposure to petroleum hydrocarbons.

  3. New reducing system: calcium metal in amines. Reduction of aromatic hydrocarbons

    SciTech Connect

    Benkeser, R.A.; Belmonte, F.G.; Kang, J.

    1983-08-26

    A new reducing system consisting of calcium dissolved in a mixture of amines (methylamine-ethylenediamine) is described. Representative aromatic hydrocarbons have been reduced by this new reagent largely to monoalkenes. Hydrocarbons like tetralin, m- and p-xylene, and indan are reduced in excellent yields by the calcium system to a crude product containing 88% or better of a single alkene. A new technique involving oxymercuration-demercuration is used to purify two of the monoalkene isomer mixtures obtained in these reductions. Unexpectedly, durene is reduced by the calcium reagent to 1,2,4,5-tetramethyl-1,4-cyclohexadiene in excellent yield. Likewise anthracene is reduced in one step to 1,2,3,4,5,6,7,8,9,10-decahydroanthracene. Experiments designed to elucidate why the calcium system does not reduce durene or anthracene to monoalkenes are described. Similarities and differences between the calcium-amine and the lithium-amine reducing systems are discussed. 1 table.

  4. Levels, Distribution, and Health Risks of Polycyclic Aromatic Hydrocarbons in Four Freshwater Edible Fish Species from the Beijing Market

    PubMed Central

    Wu, Wen-Jing; Qin, Ning; He, Wei; He, Qi-Shuang; Ouyang, Hui-Ling; Xu, Fu-Liu

    2012-01-01

    We first estimated the content of polycyclic aromatic hydrocarbons (PAHs) in the brain, liver, bladder, roe, and muscle of four species of edible freshwater fish from the Beijing market. The distribution characteristics of PAHs in these tissues and organs were analyzed to determine their health risks to humans. The results showed that the residual levels of wet weight and lipid-normalized weight ?PAHs in various tissues of these fish ranged from 0.51?ng·g?1 to 28.78?ng·g?1 and from 93.62?ng·g?1 to 8203.43?ng·g?1, respectively. The wet weight contents of ?PAHs were relatively higher in the brain and lower in the liver and muscle. But the differences were not significant. And the differences of lipid-normalized weight PAHs were significant, which in the bighead carp were found significantly the highest, followed in crucian carp, and the lowest in grass carp and carp. The contents of ?PAHs were the highest in the liver and the lowest in the brain. In the tissues with a higher lipid content, higher residual levels of PAHs were found. The carcinogenic risks for humans from residual ?PAHs in the various fish tissues were far below 10?5. PMID:23365511

  5. Laboratory spectra of cold gas phase polycyclic aromatic hydrocarbon cations, and their possible relation to the diffuse interstellar bands

    Microsoft Academic Search

    Philippe Bréchignac; Thomas Pino; Nathalie Boudin

    2001-01-01

    A novel laboratory technique is described, combining the use of supersonic expansion, laser excitation and small aromatic-rare gas van der Waals (vdW) clusters properties, which was developed to access the electronic absorption spectra of the polycyclic aromatic hydrocarbon (PAH) cations in the visible. It consists in preparing vdW complexes of the PAH molecule with a rare gas in a molecular

  6. Polycyclic aromatic hydrocarbons (PAHs) and estrogenic compounds in experimental flue gas streams.

    PubMed

    Muthumbi, W; De Boever, P; Pieters, J G; Siciliano, S; D'Hooge, W; Verstraete, W

    2003-01-01

    The importance of combustion processes as a source of substances with estrogenic activity in the environment was investigated. Wood (nontreated and treated with wood preservatives), barbecue charcoal, meat, and kitchen waste were combusted in a laboratory-scale incinerator. Flue gas emissions (particulates and gaseous pollutants) were trapped in polyurethane foam cartridges. The cartridges were subjected to Soxhlet extraction and part of the extracts redissolved in dimethylsulfoxide (DMSO) for analyses of estrogenic activity by means of the yeast-based human estrogen receptor (hER) bioassay. A synthetic estrogen, 17-alpha-ethinylestradiol (EE2), was used as the reference estrogenic compound. Part of the extracts was analyzed for the 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs). Estrogenic compounds in the flue gas (wood) were as high as 234 +/- 25 ng m(-3) EE2 equivalent compared with 27 to 81 ng m(-3) EE2 equivalent in flue gas from combustion of barbecue charcoal. Concentrations of polycyclic aromatic hydrocarbons in both flue gas streams were in the range of 21,000 +/- 2000 and 240 +/- 110 ng m(-3), respectively. In general, the concentrations of EE2 equivalent in the flue gas samples were at least a factor of 1000 lower than total PAH concentration. The EE2 levels were not related to the concentration of PAHs in any flue gas sample. PMID:12708663

  7. Trimethylphenylammonium-Smectite as an effective adsorbent of water soluble aromatic hydrocarbons

    SciTech Connect

    Jaynes, W.F.; Boyd, S.A. (Michigan State Univ., East Lansing (United States))

    1990-12-01

    Homoionic trimethylphenylammonium (TMPA)- and tetramethylammonium (TMA)-clays were prepared by ion-exchange reactions using two smectite clays that differed in their cation exchange capacities and surface charge densities. These clays are referred to as a low-charge (SAC) and high-charge (SWa)-smectite. The organo-clays were evaluated as adsorbents of water soluble aromatic hydrocarbons including benzene, toluene, ethylbenzene, p-xylene, butylbenzene, and naphthalene. All of the aromatic hydrocarbons tested were effectively removed from water by the low-charge TMPA-smectite. The low-charge TMA-smectite was an effective adsorbent for benzene but was ineffective in the removal of the alkylbenzenes and naphthalene from water. The effect of surface charge on the adsorption properties of TMPA-smectite was pronounced. The uptake of benzene and toluene by the high-charge TMPA-smectite was greatly reduced as compared to the low-charge TMPA-smectite. These results suggest the utility of TMPA-smectite as a liner material for petroleum storage containers and waste disposal reservoirs. The use of TMPA-smectite in conjunction with Na-smectite would provide a barrier with the ability to impede the flow of water and to effectively adsorb dissolved organic contaminants.

  8. Characterization and source identification of polycyclic aromatic hydrocarbons (PAHs) in the urban environment of Delhi.

    PubMed

    Sharma, Homdutt; Jain, V K; Khan, Zahid H

    2007-01-01

    This paper reports on polycyclic aromatic hydrocarbons (PAHs) in the atmospheric particulate matter of Jawaharlal Nehru University campus, an urbanized site of New Delhi, India. Suspended particulate matter samples of 24h duration were collected on glass-fiber filter paper for four representative days in each month during January 2002 to December 2003. PAHs were extracted from filter papers using toluene with ultrasonication method and analysed. Quantitative measurements of polycyclic aromatic hydrocarbons (PAHs) were carried out using the gas chromatography technique. The annual average concentration of total PAHs were found to be 668+/-399 and 672+/-388 ng/m3 in the years 2002 and 2003, respectively. The seasonal average concentrations were found to be maximum in winter and minimum during in the monsoon. The results of principal component analysis (PCA) indicate that diesel and gasoline driven vehicles are the principal sources of PAHs in all the seasons. In winter coal and wood combustion also significantly contribute to the PAH levels. PMID:16793114

  9. Chemistry of polycyclic aromatic hydrocarbons formation from phenyl radical pyrolysis and reaction of phenyl and acetylene.

    PubMed

    Comandini, A; Malewicki, T; Brezinsky, K

    2012-03-15

    An experimental investigation of phenyl radical pyrolysis and the phenyl radical + acetylene reaction has been performed to clarify the role of different reaction mechanisms involved in the formation and growth of polycyclic aromatic hydrocarbons (PAHs) serving as precursors for soot formation. Experiments were conducted using GC/GC-MS diagnostics coupled to the high-pressure single-pulse shock tube present at the University of Illinois at Chicago. For the first time, comprehensive speciation of the major stable products, including small hydrocarbons and large PAH intermediates, was obtained over a wide range of pressures (25-60 atm) and temperatures (900-1800 K) which encompass the typical conditions in modern combustion devices. The experimental results were used to validate a comprehensive chemical kinetic model which provides relevant information on the chemistry associated with the formation of PAH compounds. In particular, the modeling results indicate that the o-benzyne chemistry is a key factor in the formation of multi-ring intermediates in phenyl radical pyrolysis. On the other hand, the PAHs from the phenyl + acetylene reaction are formed mainly through recombination between single-ring aromatics and through the hydrogen abstraction/acetylene addition mechanism. Polymerization is the common dominant process at high temperature conditions. PMID:22339468

  10. Three-way analysis of fluorescence spectra of polycyclic aromatic hydrocarbons with quenching by nitromethane.

    PubMed

    Wentzell, P D; Nair, S S; Guy, R D

    2001-04-01

    The application of trilinear decomposition (TLD) to the analysis of fluorescence excitation-emission matrices of mixtures of polycyclic aromatic hydrocarbons (PAHs) is described. The variables constituting the third-order tensor are excitation wavelength, emission wavelength, and concentration of a fluorescence quencher (nitromethane). The addition of a quencher to PAH mixtures selectively reduces the fluorescence intensity of mixture components according to the Stern-Volmer equation. TLD allows the three-way matrix to be decomposed to give unique solutions for the excitation spectrum, emission spectrum, and quenching profiles for each component. The availability of spectra and calculated Stern-Volmer constants can aid in the identification of unknown components. Preprocessing of the data to correct for Rayleigh/Raman scatter and primary absorption by the quencher is necessary. Both three-component (anthracene, pyrene, 1-methylpyrene) and four-component (fluoranthene, anthracene, pyrene, 2,3-benzofluorene) synthetic mixtures are successfully resolved by TLD using quencher concentrations up to 100 mM. Results are compared using both alternating least-squares and direct trilinear decomposition algorithms. The reproducibility of extracted Stern-Volmer constants is determined from replicate experiments. To illustrate the application of TLD to a real sample, a chromatographic cut from the analysis of a light gas oil sample was used. Analysis of the TLD extracted spectra and quenching constants suggests the presence of three classes of polycyclic aromatic hydrocarbons consistent with data from a second dimension of chromatography and mass spectrometry. PMID:11321288

  11. Firefighting instructors' exposures to polycyclic aromatic hydrocarbons during live fire training scenarios.

    PubMed

    Kirk, Katherine M; Logan, Michael B

    2015-01-01

    Cumulative exposures of firefighting instructors to toxic contaminants generated from live-fire training potentially far exceed firefighter exposures arising from operational fires. This study measured the atmospheric concentrations of polycyclic aromatic hydrocarbons (PAHs) outside and inside the structural firefighting ensembles worn by instructors during five live fire training evolutions. In addition, the contamination of ensembles by deposition of PAHs was characterized. Concentrations of polycyclic aromatic hydrocarbons outside the instructors' structural firefighting ensembles during the training evolutions ranged from 430 ?g/m(3) to 2700 ?g/m(3), and inside the structural firefighting ensembles from 32 ?g/m(3) to 355 ?g/m(3). Naphthalene, phenanthrene and acenaphthylene dominated the PAHs generated in the live fire evolutions, but benzo[a]pyrene was the greatest contributor to the toxicity of the PAH mixture both inside and outside the structural firefighting ensembles. Deposition of PAHs onto the structural firefighting ensembles was measured at between 69 and 290 ng/cm(2), with phenanthrene, fluoranthene, pyrene, and benzo[a]anthracene detected on all samples. These findings suggest that firefighting instructor exposures to PAHs during a single live-fire training evolution are comparable with exposures occurring in industrial settings over a full shift. Further research is required to investigate the importance of various potential routes of exposure to PAHs as a result of ingress and deposition of PAHs in/on structural firefighting ensembles. PMID:25679824

  12. [Evaluation of occupational exposure to aromatic polycyclic hydrocarbons in bituminous pulp plants].

    PubMed

    Bara?ski, Z

    1991-01-01

    A method was developed for isolation of aromatic polycyclic hydrocarbons (APH) from atmospheric air. Air samples were filtered through Whatman GF/C filter papers, subsequently extracted with benzene. Aromatic polycyclic hydrocarbons were isolated from the extract, purified by column chromatography on aluminium oxide and determined by gas chromatography. This method was applied to determine qualitatively and quantitatively: naphthalene, anthracene, pyrene, perilene, biphenyl, fluoranthene, phenanthrene, benzo(a)pyrene, dibenzo(a,c)anthracene, dibenzo(g,h)anthracene, 11H-benzo(a)fluorane, 11H-benzo(b)fliorene, benzo(g,h,i)perylene, benzo(a)anthracene, chrysene, indene and durene. Professional exposure in years 1977-1989 was comparatively assessed using the evaluation criterion for APH expressed as the benzene fraction (0.2 mg/m3--USA standard) and as benzo(a)pyrene (0.00015 mg/m3--USSR standard). According to the accepted standards, working conditions in the examined plants entail a risk for the employees. Comparison of the results obtained before and after reconditioning of the machinery suggests the need for further modernization aimed at application of new technical solutions allowing for limitation of pollutant emission to air. PMID:1841435

  13. Polycyclic aromatic hydrocarbon formation mechanism in the "particle phase". A theoretical study.

    PubMed

    Indarto, Antonius; Giordana, Anna; Ghigo, Giovanni; Maranzana, Andrea; Tonachini, Glauco

    2010-08-28

    The synthesis of polycyclic aromatic hydrocarbons (PAHs) and the formation of soot platelets occur both during combustion at relatively low [O(2)], or under pyrolysis conditions. When the PAH size grows beyond the number of three-four condensed cycles, the partitioning of PAHs between the gas and particle phases favours the latter (i.e. adsorption). This study aims to assess which role the soot particle plays during PAH synthesis, in particular if catalytic or template effects of some sort can be exerted by the soot platelet on the adsorbed growing PAH-like radical. Our theoretical calculations indicate that chain elongation by ethyne addition cannot compete with cyclization when both can take place in the growing PAH-like radical, already in the gas phase. When it is adsorbed, cyclization is found to become easier than in the gas phase (more so, in terms of Gibbs free energy barriers, at higher temperatures), hinting at some sort of template effect, while chain elongation by ethyne addition becomes somewhat more difficult. The underlying soot platelet can assist (at lower temperatures) the formation of a larger aromatic hydrocarbon, by a final hydrogen abstraction from that endocyclic saturated carbon the newly formed cycle still bears. As an alternative (at higher temperature), a spontaneous hydrogen atom loss can take place. Finally, at rather low temperatures, the addition of the growing radical to the underlying soot platelet might occur and cause some reticulation, form more disordered structures, i.e. soot precursors instead of PAHs. PMID:20589277

  14. Gas-phase ion/molecule reactions between dimethoxyphosphonium ions and aromatic hydrocarbons.

    PubMed

    Leclerc, Eric; Buchmann, William; Taphanel, Marie-Hélène; Morizur, Jean-Pierre

    2002-01-01

    Ion/molecule reactions between O=P(OCH(3))(2)(+) phosphonium ions and six aromatic hydrocarbons (benzene, toluene, 1,2,4-trimethylbenzene, naphthalene, acenaphthylene and fluorene) were performed in a quadrupole ion trap mass spectrometer. The O=P(OCH(3))(2)(+) phosphonium ions, formed by electron impact from neutral trimethyl phosphite, were found to react with aromatic hydrocarbons (ArHs) to give (i) an adduct [ArH, O=P(OCH(3))(2)](+) and (ii) for ArHs which have an ionization energy below or equal to 8.14 eV, a radical cation ArH(+ *) by charge transfer reaction. Collision-induced dissociation experiments, which produce fragment ions other than the O=P(OCH(3))(2)(+) ions, indicate that the adduct ions are covalent species. Isotope-labeled ArHs were used to elucidate fragmentation mechanisms. The charge transfer reactions were investigated using density functional theory at the B3LYP/6-311 + G(3df,2p)//B3LYP/6-31G(d,p) level of theory. The potential energy surface obtained from B3LYP/6-31G(d,p) calculations for the reaction between O=P(OCH(3))(2)(+) and benzene is described. PMID:11921248

  15. Genomic analysis of polycyclic aromatic hydrocarbon degradation in Mycobacterium vanbaalenii PYR-1.

    PubMed

    Kim, Seong-Jae; Kweon, Ohgew; Jones, Richard C; Edmondson, Ricky D; Cerniglia, Carl E

    2008-11-01

    Mycobacterium vanbaalenii PYR-1 is well known for its ability to degrade a wide range of high-molecular-weight (HMW) polycyclic aromatic hydrocarbons (PAHs). The genome of this bacterium has recently been sequenced, allowing us to gain insights into the molecular basis for the degradation of PAHs. The 6.5 Mb genome of PYR-1 contains 194 chromosomally encoded genes likely associated with degradation of aromatic compounds. The most distinctive feature of the genome is the presence of a 150 kb major catabolic region at positions 494 approximately 643 kb (region A), with an additional 31 kb region at positions 4,711 approximately 4,741 kb (region B), which is predicted to encode most enzymes for the degradation of PAHs. Region A has an atypical mosaic structure made of several gene clusters in which the genes for PAH degradation are complexly arranged and scattered around the clusters. Significant differences in the gene structure and organization as compared to other well-known aromatic hydrocarbon degraders including Pseudomonas and Burkholderia were revealed. Many identified genes were enriched with multiple paralogs showing a remarkable range of diversity, which could contribute to the wide variety of PAHs degraded by M. vanbaalenii PYR-1. The PYR-1 genome also revealed the presence of 28 genes involved in the TCA cycle. Based on the results, we proposed a pathway in which HMW PAHs are degraded into the beta-ketoadipate pathway through protocatechuate and then mineralized to CO2 via TCA cycle. We also identified 67 and 23 genes involved in PAH degradation and TCA cycle pathways, respectively, to be expressed as proteins. PMID:18421421

  16. Emissions of polycyclic aromatic hydrocarbons from batch hot mix asphalt plants.

    PubMed

    Lee, Wen-Jhy; Chao, Wen-Hui; Shih, Minliang; Tsai, Cheng-Hsien; Chen, Thomas Jeng-Ho; Tsai, Perng-Jy

    2004-10-15

    This study was set out to assess the characteristics of polycyclic aromatic hydrocarbon (PAH) emissions from batch hot mix asphalt (HMA) plants and PAH removal efficiencies associated with their installed air pollution control devices. Field samplings were conducted on six randomly selected batch HMA plants. For each selected plant, stack flue gas samples were collected from both stacks of the batch mixer (n = 5) and the preheating boiler (n = 5), respectively. PAH samples were also collected from the field to assess PAHs that were directly emitted from the discharging chute (n = 3). To assess PAH removal efficiencies of the installed air pollution control devices, PAH contents in both cyclone fly ash (n=3) and bag filter fly ash (n = 3) were analyzed. Results show that the total PAH concentration (mean; RSD) in the stack flue gas of the batch mixer (354 microg/Nm3; 78.5%) was higher than that emitted from the discharging chute (107 microg/Nm3; 70.1%) and that in the stack flue gas of the preheating boiler (83.7 microg/Nm3; 77.6%). But the total BaPeq concentration of that emitted from the discharging chute (0.950 microg/Nm3; 84.4%) was higher than contained in the stack flue gas of the batch mixer (0.629 microg/Nm3; 86.8%) and the stack flue gas of the preheating boiler (= 0.112 microg/Nm3; 80.3%). The mean total PAH emission factor for all selected batch mix plants (= 139 mg/ton x product) was much higher than that reported by U.S. EPA for the drum mix asphalt plant (range = 11.8-79.0 mg/ton x product). We found the overall removal efficiency of the installed air pollution control devices (i.e., cyclone + bag filter) on total PAHs and total BaPeq were 22.1% and 93.7%, respectively. This implies that the installed air pollution control devices, although they have a very limited effect on the removal of total PAHs, do significantly reduce the carcinogenic potencies associated with PAH emissions from batch HMA plants. PMID:15543726

  17. Host and environmental determinants of polychlorinated aromatic hydrocarbons in serum of adolescents.

    PubMed Central

    Nawrot, Tim S; Staessen, Jan A; Den Hond, Elly M; Koppen, Gudrun; Schoeters, Greet; Fagard, Robert; Thijs, Lutgarde; Winneke, Gerhard; Roels, Harry A

    2002-01-01

    This study investigated host factors and environmental factors as potential determinants of polychlorinated aromatic hydrocarbons (PCAHs) in serum of adolescents. We recruited 200 participants (80 boys and 120 girls), with a mean age of 17.4 years (SD, 0.8), in Belgium from a rural control area (Peer) and from two polluted suburbs of Antwerp where a nonferrous smelter (Hoboken) and waste incinerators (Wilrijk) are located. We quantified polychlorinated biphenyls (PCBs; congeners 138, 153, and 180) in serum by gas chromatography and obtained the toxic equivalents (TEQs) of PCAHs in serum with the chemically activated luciferase gene expression bioassay (CALUX). Serum PCB concentration was higher in boys than in girls (1.67 vs. 1.02 nmol/L or 377 vs. 210 pmol/g serum lipids; p< 0.001). In the whole adolescent group, multiple regression showed that serum PCB concentration decreased 0.06 nmol/L per 1% increase in body fat content (p< 0.001) and increased 0.39 nmol/L and 0.14 nmol/L per 1 mmol/L increase in serum concentrations of triglycerides (p < 0.001) and cholesterol (p = 0.002), respectively. Host factors explained 44% of the serum PCB variance. In the same model, serum PCB concentration increased 0.14 nmol/L with 10 weeks of breast-feeding (p< 0.001) and 0.06 nmol/L with intake of 10 g animal fat per day (p < 0.001), and was associated with residence in the waste incinerator area (9% higher; p = 0.04); 11% of the variance could be explained by these environmental factors. The geometric mean of the serum TEQ value was similar in boys and girls (0.15 TEQ ng/L or 33.0 pg/g serum lipids). In multiple regression, TEQ in serum decreased 0.03 ng/L per centimeter increase in triceps skinfold (p = 0.006) and was 29% higher in subjects living close to the nonferrous smelter (p < 0.001). This study showed that in 16- to 18-year-old teenagers host factors are important determinants of serum concentrations of PCAHs, whereas environmentally related determinants may to some extent contribute independently to human exposure to these persistent chemicals in the environment. PMID:12055049

  18. Development of laboratory reference material: Soil 1. Baseline and highly elevated concentrations of metals and polycyclic aromatic hydrocarbons.

    PubMed

    Kupiec, K; Konieczka, P; Namie?nik, J

    2011-01-01

    Reference materials play a key part in systems of inspection and quality control of results of analytical measurements. The main limitation in using certified reference materials (CRM) is their high price, which results from the long and costly process of producing the reference material. An alternative to costly CRM materials is the employment of laboratory reference materials, particularly for interlaboratory control of measurement results and procedures. Under the auspices of the Chair of Analytical Chemistry at the Chemical Department of Gdansk University of Technology, research on the development of new reference materials is being conducted. At present, the research is aimed at producing a new laboratory reference material (LRM): 'Soil 1. Baseline and Highly Elevated Concentrations of Metals and Polycyclic Aromatic Hydrocarbons' - LRM soil 1. This paper presents the production stages of the developed laboratory reference material: acquisition of raw material from soil samples taken from the environment of the Tri-city (in Polish, Trójmiasto Gdansk, Sopot, Gdynia) bypass road, homogenization and subsequent dosage into appropriate containers, tests of homogeneity of sampled material within one container and between containers, based on the results of the determination of selected parameters (total carbon, content of optional metals - Hg, Fe, Cu Zn, Mn, Mg, water content, content of PAH-group analytes). The obtained results of homogeneity tests of the proposed future laboratory reference material have confirmed the homogeneity of soil samples within a container and between containers. Currently, interlaboratory tests are being carried out to determine the reference value. PMID:21473281

  19. Eco-physiological Effects of Atmospheric Ozone and Polycyclic Aromatic Hydrocarbons (PAHs) on Plants

    NASA Astrophysics Data System (ADS)

    Bandai, S.; Sakugawa, H. H.

    2012-12-01

    [Introduction] Tropospheric ozone is one of most concerned air pollutant, by causing damage to trees and crops. Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous contaminants found in various environmental compartments. Photo-induced toxicity of PAHs can be driven from formation of intracellular single oxygen and other reactive oxygen intermediates (ROI) leading to biological damages.(1) In the present study, we measured photosynthesis rate and other variables to investigate the effects of ozone and PAHs on the eco-physiological status of plants such as eggplant, common bean and strawberry. Plants treated with the single or combined air pollutants are expected to exhibit altered physiological, morphological and possibly growth changes. [Materials and Methods] We performed three exposure experiments. Exp.1. Eggplant (Solanum melongena) seedlings, were placed in the open-top chambers (n=6 plants/treatment). Treatment system was ozone (O)(120ppb), phenanthrene (P)(10?M), O+P, fluoranthene (F)(10?M), O+F, mannitol (M)(1mM) and the control (Milli-Q water)(C). P, F and M were sprayed three times weekly on the foliage part of eggplant. Average volume sprayed per seedling was 50mL. The treatment period was 30days and [AOT 40 (Accumulated exposure over a threshold of 40 ppb)]=28.8 ppmh. Exp.2, Common bean (Phaseolus vulgaris L.) seedlings were used (n=5 plants/treatment). The treatment system was the same as Exp.1. The treatment period was 40days and [AOT 40]=38.4ppmh. Exp.3. Strawberry (Fragaria L.) seedlings were used (n=5 plants/treatment). Treatment system was O (120ppb), F(10?M), O+F, F+M, O+M and C. The treatment period was 90days and [AOT 40]=86.4ppmh. Ecophysiological variables examined were photosynthesis rate measured at saturated irradiance (Amax), stomatal conductance to water vapour (gs), internal CO2 concentration (Ci), photochemical efficiency of PS2 in the dark (Fv/Fm), chlorophyll contents, visual symptom assessment and elemental composition in the leaves. [Results and Discussion] The P+O and O treatments caused a large decrease in Amax values of eggplant and common bean leaves and the P treatment made a little decrease in the Amax . Other parameters those were reduced by the O+P, O and P treatments were gs, Fv/Fm, Chlorophyll contents, and elemental composition. The F treatment made more decrease in Amax, gs and chlorophyll contents in eggplant leaves than those in the P treatment. The O treatment significantly decreased Amax, gs, Fv/Fm and chlorophyll contents in the Exp. 3. From the results mentioned above, it was concluded that phenanthrene and fluoranthene deposited onto leaves, combined with ozone fumigations, negatively affected growth and quality of plants. In addition, all plants fumigated with O, P, F, O+P and O+F showed severe visible symptoms on the foliage during the exposure period. We also note that mannitol, a reactive oxygen scavenger, mitigated negative effects of the F+O, O, P and F on plants and therefore mannitol could be useful for protection of plant from air pollutants. (1) Huang X, Lorelei F, Dixon D, Greenberg B (1996) Ecotoxicology and Environmental Safety, Volume 35 (2), 101-197.

  20. Monooxygenase activities in carp as biochemical markers of pollution by polycyclic and polyhalogenated aromatic hydrocarbons: choice of substrates and effects of temperature, gender and capture stress

    Microsoft Academic Search

    Miroslav Machala; Karel Nezveda; Marek Pet?ivalský; Alžb?ta Jarošová; Vladimír Pia?ka; Zdenka Svobodová

    1997-01-01

    Cytochrome P450-dependent monooxygenase activities (7-ethoxyresorufin, 7-pentoxyresorufin and 7-ethoxycoumarin O-dealkylases and aminopyrine N-demethylase) were measured in hepatopancreatic microsomes of carp collected in one control and one polychlorinated biphenyl- and polycyclic aromatic hydrocarbon-polluted ponds in the Czech Republic. The magnitudes of responses of monooxygenase activities to the exposure to polycyclic and polyhalogenated aromatic compounds (PAC), namely polycyclic aromatic hydrocarbons and polychlorinated biphenyls,

  1. Comparison of polycyclic aromatic hydrocarbon distributions and sedimentary organic matter characteristics in contaminated, coastal sediments from Pensacola Bay, Florida

    Microsoft Academic Search

    Myrna J. Simpson; Benny Chefetz; Ashish P. Deshmukh; Patrick G. Hatcher

    2005-01-01

    In this study, we examined the distribution of polycyclic aromatic hydrocarbons (PAHs) in a contaminated coastal area and the characteristics of the natural organic matter in tandem. We present a detailed study of PAH concentration, distribution, and organic matter characteristics of three core samples from Pensacola Bay, Florida. Solid-state 13C Nuclear Magnetic Resonance (NMR), pyrolysis gas chromatography coupled with mass

  2. SPECTRAL FINGERPRINTING OF POLYCYCLIC AROMATIC HYDROCARBONS IN HIGH-VOLUME AMBIENT AIR SAMPLES BY CONSTANT ENERGY SYNCHRONOUS LUMINESCENCE SPECTROSCOPY

    EPA Science Inventory

    A high-volume sampler fitted with a glass-fiber filter and backed by polyurethane foam (PUF) was employed to collect airborne particulate and gas-phase polycylic aromatic hydrocarbons (PAHs) in ambient air. Samples were collected from four sources representing a range of environm...

  3. IMPACTS OF AGING ON IN VIVO AND IN VITRO MEASUREMENTS OF SOIL-BOUND POLYCYCLIC AROMATIC HYDROCARBON AVAILABILITY

    EPA Science Inventory

    Ingestion of contaminated soil is an exposure pathway at approximately one-half of the Superfund sites in the United States. This study was designed to evaluate the impacts of aging in soil on the availability of polycyclic aromatic hydrocarbons (PAHs). Two coal tar (CT)-amended ...

  4. Effect of soil structure on the bioavailability of polycyclic aromatic hydrocarbons within aggregates of a contaminated soil

    Microsoft Academic Search

    N Amellal; J.-M Portal; J Berthelin

    2001-01-01

    Biodegradation of polycyclic aromatic hydrocarbon (PAH) was investigated in the whole matrix and in the different aggregate size fractions of a sandy soil contaminated by a mixture of 8 PAHs and incubated at water holding capacity. The distribution of PAHs and of phenanthrene-degrading bacteria were determined in the bulk soil and in 4 size aggregate fractions corresponding to sand, coarse

  5. Polycyclic aromatic hydrocarbon contamination of American lobster, Homarus americanus , in the proximity of a coal-coking plant

    Microsoft Academic Search

    J. F. Uthe; C. J. Musial

    1986-01-01

    Polycyclic aromatic hydrocarbons (PAH) are ubiquitous environmental contaminants resulting predominantly from anthropogenic pyrolytic and combustion processes (NRCC 1983). In addition to the usual methods of aerial and aqueous transport to the coastal marine environment substantial amounts of PAH are added through the use of products such as creosote, coal tar and coal tar pitch as preservative and antifouling agents in

  6. Occupational exposures to polycyclic aromatic hydrocarbons, and respiratory and urinary tract cancers: a quantitative review to 2005

    Microsoft Academic Search

    C. Bosetti; P. Boffetta; C. La Vecchia

    2006-01-01

    Background: Exposure to polycyclic aromatic hydrocarbons (PAHs) has been reported in several industries, including those of the aluminum production, coal gasification, coke production, iron and steel foundries, coal tar and related products, carbon black and carbon electrodes production. Patients and methods: This paper reviews the results from cohort studies conducted on workers exposed to PAHs in these industries, with a

  7. CONCENTRATION AND DISTRIBUTION OF POLYCYCLIC AROMATIC HYDROCARBONS (PAHs) IN THE TOWN OF KOTA BHARU, KELANTAN DARUL NAIM

    Microsoft Academic Search

    Muhammad Fais Fadzil; Norhayati Mohd Tahir; Wan Mohd; Khairul Wan; Mohd Zin

    This study was carried out to determine the concentration and distribution of polycyclic aromatic hydrocarbons (PAHs) in soils of Kota Bharu, Kelantan Darul Naim. A total of 20 sampling sites were chosen covering the town center and surrounding suburban area of this district. PAHs in soil matrix were extracted using ultrasonic agitation technique with dichloromethane as extraction solvent. Fractionation of

  8. doi:10.1016/j.gca.2004.09.009 Alkylation of polycyclic aromatic hydrocarbons in carbonaceous chondrites

    E-print Network

    Zare, Richard N.

    , is in a solvent-extractable form containing aromatic and aliphatic hydrocarbons, amino acids, and other compounds no detectable levels of typical meteoritic PAHs. This observation might be explained either by a loss of PAHs primitive solid materials in the solar system. Carbo- naceous chondrites contain up to 3% carbon by weight

  9. Determination of Firefighter Exposure to Polycyclic Aromatic Hydrocarbons and Benzene During Fire Fighting Using Measurement of Biological Indicators

    Microsoft Academic Search

    Chantal Caux; Cindy OBrien; Claude Viau

    2002-01-01

    In accomplishing their duties, firefighters are potentially exposed to a vast array of toxic combustion and pyrolysis products such as benzene, carbon monoxide, acrolein, nitrogen dioxide, and polycyclic aromatic hydrocarbons. Exposure to PAH and benzene was assessed by means of urinary measurements of 1-hydroxypyrene and t,t -muconic acid, respectively. All urine samples were collected from 43 firefighters during a period

  10. Comparison of polycyclic aromatic hydrocarbon levels in placental tissues of Indian women with full- and preterm deliveries

    Microsoft Academic Search

    Vipul Kumar Singh; Jyoti Singh; Madhu Anand; Prabhat Kumar; Devendra Kumar Patel; Mudiam Mohana Krishna Reddy; Mohammed Kaleem Javed Siddiqui

    2008-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental contaminants formed from combustion products of fossil fuels, cigarette smoking and in grilled\\/smoked foods. They are reported to alter trophoblast proliferation in placenta, in addition to disturbing its endocrine functions, which may be able to increase the risk of preterm delivery in pregnant women. The present study was planned to assess possible involvement

  11. COMPARATIVE POTENCY APPROACH FOR ESTIMATING THE CANCER RISK ASSOCIATED WITH EXPOSURE TO MIXTURES OF POLYCYCLIC AROMATIC HYDROCARBONS

    EPA Science Inventory

    A relative potency approach was developed as a method for assessing the cancer risk of polycyclic aromatic hydrocarbons (PAHS) for which inadequate ingestion or inhalation bioassay data exist. his approach takes into account the differing potencies of carcinogenic PAHs rater than...

  12. MONITORING METHODS FOR POLYCYCLIC AROMATIC HYDROCARBONS AND THEIR DISTRIBUTION IN HOUSE DUST AND TRACK-IN SOIL

    EPA Science Inventory

    An analytical method was developed and employed to determine polycyclic aromatic hydrocarbons (PAH) in house dust and soil. he method was applied to the analysis of samples collected in an eight-home pilot study that was conducted in Columbus, OH, before and after the 1992/1993 h...

  13. Catalytic conversion of isophorone to jet-fuel range aromatic hydrocarbons over a MoOx/SiO2 catalyst.

    PubMed

    Chen, Fang; Li, Ning; Wang, Wentao; Wang, Aiqin; Cong, Yu; Wang, Xiaodong; Zhang, Tao

    2015-07-01

    For the first time, jet fuel range C8-C9 aromatic hydrocarbons were synthesized in high carbon yield (?80%) by the catalytic conversion of isophorone over MoOx/SiO2 at atmospheric pressure. A possible reaction pathway was proposed according to the control experiments and the intermediates generated during the reaction. PMID:26110372

  14. Trace elements, organochlorines, polycyclic aromatic hydrocarbons, dioxins, and furans in lesser scaup wintering on the Indiana Harbor Canal

    Microsoft Academic Search

    T. W. Custer; C. M. Custer; R. K. Hines; D. W. Sparks

    2000-01-01

    During the winter of 1993–94, male lesser scaup (Aythya affinis) were collected on the heavily polluted Indiana Harbor Canal (IHC), East Chicago, IN, USA, and examined for tissue contaminant levels. Lesser scaup collected on the IHC had higher concentrations of cadmium (Cd), mercury (Hg), selenium (Se), polychlorinated biphenyls (PCBs), selected organchlorine pesticides, polychlorinated dibenzodioxins, polychlorinated dibenzofurans, polycyclic aromatic hydrocarbons, and

  15. CYCLOPENTA-FUSED POLYCYCLIC AROMATIC HYDROCARBONS IN STRAIN A/J MOUSE LUNG: DNA ADDUCTS, ONCOGENE MUTATIONS, & TUMORIGENESIS

    EPA Science Inventory

    Cyclopenta-fused Polycyclic Aromatic Hydrocarbons in Strain AJJ Mouse Lung: DNA Adducts, Oncogene Mutations, and Tumorigenesis. We have examined the relationships between DNA adducts, Ki-ras oncogene mutations, DNA adducts, and adenoma induction in the lungs of strain A/J...

  16. Bioremediation of high molecular weight polycyclic aromatic hydrocarbons: a review of the microbial degradation of benzo[ a]pyrene

    Microsoft Academic Search

    Albert L. Juhasz; Ravendra Naidu

    2000-01-01

    Over the past 30 years, research on the microbial degradation of polycyclic aromatic hydrocarbons (PAHs) has resulted in the isolation of numerous genera of bacteria, fungi and algae capable of degrading low molecular weight PAHs (compounds containing three or less fused benzene rings). High molecular weight PAHs (compounds containing four or more fused benzene rings) are generally recalcitrant to microbial

  17. EVALUATION OF A METHOD FOR SAMPLING AND ANALYSIS OF NICOTINE AND POLYNUCLEAR AROMATIC HYDROCARBONS IN INDOOR AIR

    EPA Science Inventory

    A study was performed to determine whether one sampling system and one analytical method can be used to measure both polynuclear aromatic hydrocarbons (PAH) and nicotine. he PAH collection efficiencies for both XAD-2 and XAD-4 adsorbents are very similar, but the nicotine collect...

  18. Cumulative Exposure Assessment for Trace-Level Polycyclic Aromatic Hydrocarbons (PAHs) using Human Blood and Plasma Analysis

    EPA Science Inventory

    Humans experience chronic cumulative trace-level exposure to mixtures of volatile, semi-volatile, and non-volatile polycyclic aromatic hydrocarbons (PAHs) present in the environment as by-products of combustion processes. Certain PAHs are known or suspected human carcinogens and ...

  19. Analytical modeling of polycyclic aromatic hydrocarbon loading and transport via road runoff in an urban region of Beijing, China

    Microsoft Academic Search

    Wei Zhang; Arturo A. Keller; Xuejun Wang

    2009-01-01

    An analytical runoff water quality model is developed for simulating polycyclic aromatic hydrocarbon (PAH) loading and transport via road runoff in an urban area. The model considers buildup and washoff processes of suspended solids in storm runoff and considers dissolved and particle-bound PAHs. Pollutant deposition and removal processes, which have typically been treated with a constant rate in previous models,

  20. Chemical and ecotoxicological assessment of polycyclic aromatic hydrocarbon—contaminated sediments of the Niger Delta, Southern Nigeria

    Microsoft Academic Search

    Abass A. Olajire; Rolf Altenburger; Eberhard Küster; Werner Brack

    2005-01-01

    The extent of environmental contamination and sources of polycyclic aromatic hydrocarbons (PAHs) compounds to sediments of the Niger Delta, Nigeria were assessed using combined chemical analysis and toxicity bioassay techniques. Concentrations of two- to six-ring PAHs of molecular mass 128–278 and toxicity to Vibrio fischeri and Lemna minor are considered in this investigation. Levels of the sum of the 16

  1. SEMIPERMEABLE MEMBRANE DEVICE-AVAILABILITY OF POLYCYCLIC AROMATIC HYDROCARBONS IN RIVER WATERS AND WASTEWATER TREATMENT PLANT EFFLUENTS

    Microsoft Academic Search

    C. Miège; S. Durand; J. Garric; C. Gourlay; D. Wang; J.-M. Mouchel; M.-H. Tusseau-Vuillemin

    2004-01-01

    River waters and wastewater treatment plant effluents contain hydrophobic organic compounds (HOCs) such as polycyclic aromatic hydrocarbons (PAHs) which are persistent, bioaccumulative, and dangerous for the environment. The biological risk assessment of HOCs requires the estimation of their bioavailable fraction in addition to the total contamination of the media. The bioavailability of HOCs depends on the characteristics of the aquatic

  2. FISH BILIARY POLYCYCLIC AROMATIC HYDROCARBON METABOLITES ESTIMATED BY FIXED-WAVELENGTH FLUORESCENCE: COMPARISON WITH HPLC-FLUORESCENT DETECTION

    EPA Science Inventory

    Fixed wavelength fluorescence (FF) was compared to high-performance liquid chromatography with fluorescence detection (HPLC-F) as an estimation of polycyclic aromatic hydrocarbon (PAH) exposure to fish. Two excitation/emission wavelength pairs were used to measure naphthalene- an...

  3. Concentrations and deposition fluxes of polynuclear aromatic hydrocarbons and heavy metals in the dated sediments of a rural English lake

    Microsoft Academic Search

    Gordon Sanders; Kevin C. Jones; John Hamilton-Taylor; H. Doerr

    1993-01-01

    Deposition fluxes have been estimated from concentrations of 12 polynuclear aromatic hydrocarbons (PAHs) and six heavy metals measured in sediment cores from Esthwaite Water, a rural English lake. Atmospheric deposition is a major source of PAHs and heavy metals (Cd, Cu, Pb, and Zn) to the lake, so trends in the core may indicate the long-term record of changes in

  4. Reduction of carcinogenic polycyclic aromatic hydrocarbons in meat by sugar-smoking and dietary exposure assessment in taiwan.

    PubMed

    Chen, Shaun; Kao, Tsai Hua; Chen, Chia Ju; Huang, Chung Wei; Chen, Bing Huei

    2013-08-01

    Polycyclic aromatic hydrocarbons (PAHs) represent an important pollutant in foods and/or the environment. This study aimed to determine the PAH contents in sugar-smoked meat by employing a quick, easy, cheap, effective, rugged, safe (QuEChERS) method combined with a GC-MS technique and assess the dietary exposure of PAHs in Taiwan. Results showed that the longer the sugar-smoking duration, the more the total PAH formation. By sugar-smoking for 6 min, the total PAH contents generated in red meat (33.9 ± 3.1-125.5 ± 9.2 ppb) were higher than in poultry meat (19.1 ± 2.0-28.2 ± 1.2 ppb) and seafood (9.1 ± 1.4-31.8 ± 1.8 ppb), with lamb steak containing the largest amount of total PAHs. Most importantly, the highly carcinogenic benzo[a]pyrene remained undetected in all of the sugar-smoked meat samples. In addition, the cancer risk due to dietary PAH exposure based on total intake of meat in Taiwan was <2 × 10(-7). This outcome demonstrates that sugar-smoking can be adopted to replace the traditional smoking process with wood as smoke source. PMID:23855713

  5. Effect of fuel and kiln type on the polycyclic aromatic hydrocarbon (PAH) levels in smoked shrimp, a Beninese food condiment.

    PubMed

    Kpoclou, Euloge Yénoukounmè; Anihouvi, Victor Bienvenu; Azokpota, Paulin; Soumanou, Mohamed Mansourou; Douny, Caroline; Brose, François; Hounhouigan, Djidjoho Joseph; Scippo, Marie-Louise

    2014-01-01

    Smoked shrimp is a food condiment widely used in Beninese local cooking practices. A previous study revealed that this product is highly contaminated with polycyclic aromatic hydrocarbons (PAH). The present study explored possibilities to reduce PAH levels in shrimp smoked using cottage industry smoking techniques with barrel and chorkor kilns, by replacing wood by charcoal from Acacia auriculiformis and Mangifera indica, as fuels. Results showed that only shrimp smoked using acacia charcoal in a chorkor kiln had PAH levels (benzo[a]pyrene = 5 µg kg(-1) and sum of benzo[a]pyrene, chrysene, benzo[a]anthracene and benzo[b]fluoranthene = 28 µg kg(-1)) in accordance with a European standard of 5 and 30 µg kg(-1), respectively, and suitable physicochemical characteristics for good storage (moisture content = 11.9% ± 1.5%; water activity = 0.46 ± 0.03). However, further investigations still needs to be done to reduce the duration of product contact with combustion gasses in order to reduce the PAH content of smoked shrimp to safer levels, largely below standards. PMID:24762007

  6. Extracellular polymeric substances govern the development of biofilm and mass transfer of polycyclic aromatic hydrocarbons for improved biodegradation.

    PubMed

    Zhang, Yinping; Wang, Fang; Zhu, Xiaoshu; Zeng, Jun; Zhao, Qiguo; Jiang, Xin

    2015-10-01

    The hypothesis that extracellular polymeric substances (EPS) affect the formation of biofilms for subsequent enhanced biodegradation of polycyclic aromatic hydrocarbons was tested. Controlled formation of biofilms on humin particles and biodegradation of phenanthrene and pyrene were performed with bacteria and EPS-extracted bacteria of Micrococcus sp. PHE9 and Mycobacterium sp. NJS-P. Bacteria without EPS extraction developed biofilms on humin, in contrast the EPS-extracted bacteria could not attach to humin particles. In the subsequent biodegradation of phenanthrene and pyrene, the biodegradation rates by biofilms were significantly higher than those of EPS-extracted bacteria. Although, both the biofilms and EPS-extracted bacteria showed increases in EPS contents, only the EPS contents in biofilms displayed significant correlations with the biodegradation efficiencies of phenanthrene and pyrene. It is proposed that the bacterial-produced EPS was a key factor to mediate bacterial attachment to other surfaces and develop biofilms, thereby increasing the bioavailability of poorly soluble PAH for enhanced biodegradation. PMID:26141288

  7. Towards a Solution of the Polycyclic Aromatic Hydrocarbon - Diffuse Interstellar Band Hypothesis

    E-print Network

    Xiaofeng Tan

    2006-08-31

    A novel theoretical method is developed to study the polycyclic aromatic hydrocarbon - diffuse interstellar band (PAH-DIB) hypothesis. In this method, a computer program is used to enumerate all PAH molecules with up to a specific number of fused benzene rings. Fast quantum chemical calculations are then employed to calculate the electronic transition energies, oscillator strengths, and rotational constants of these molecules. An electronic database of all PAHs with up to any specific number of benzene rings can be constructed this way. Comparison of the electronic transition energies, oscillator strengths, and rotational band contours of all PAHs in the database with astronomical spectra allows one to identify possible individual PAH carriers of some of the intense narrow DIBs. Using the current database containing up to 10 benzene rings we have selected 8 closed-shell PAHs as possible carriers of the intense lambda6614 DIB.

  8. Identification and Spectral Properties of Polycyclic Aromatic Hydrocarbons in Carbonaceous Soot Produced by Laser Pyrolysis

    NASA Astrophysics Data System (ADS)

    Jäger, C.; Krasnokutski, S.; Staicu, A.; Huisken, F.; Mutschke, H.; Henning, Th.; Poppitz, W.; Voicu, I.

    2006-10-01

    Carbon soot has been prepared by laser-induced pyrolysis of a mixture of ethylene (C2H4) and benzene (C6H6) vapor. The soluble part of the carbonaceous powder has been separated from its insoluble counterpart by soxhlet extraction in toluene. Several techniques were applied to obtain information on the composition of the extract. These included UV/visible and IR spectroscopy in solid and liquid phase, gas chromatography combined with mass spectrometry, gas-phase laser spectroscopy in a supersonic jet, and matrix spectroscopy in helium droplets, the latter being also combined with mass spectrometry. The analysis revealed that the carbonaceous powder contained various polycyclic aromatic hydrocarbons (PAHs). The highest concentration was found for the three-membered catacondensed PAHs, phenanthrene and anthracene. The results are discussed in view of the possible role of these molecules as interstellar dust components.

  9. Investigation of the Reactions and Distribution of Polycyclic Aromatic Hydrocarbons and Fullerenes in Extraterrestrial Material

    NASA Technical Reports Server (NTRS)

    Zare, Richard N.

    2005-01-01

    The work funded by this research grant includes four specific projects: (1) Mapping the spatial distribution of polycyclic aromatic hydrocarbons (PAHs) in a variety of meteoritic samples and comparing this distribution with mineralogical features of the meteorite to determine whether a correlation exists between the two. (2) Developing a method for detection of fullerenes in extraterrestrial samples using microprobe laser-desorption laser-ionization mass spectrometry ( pL2MS) and utilizing this technique to investigate fullerene presence, while exploring the possibility of spatially mapping the fullerene distribution in these samples through in situ detection. (3) Investigating a possible formation pathway for meteoritic and ancient terrestrial kerogen involving the photochemical reactions of PAHs with alkanes under prebiotic and astrophysically relevant conditions. (4) Studying reaction pathways and identifying the photoproducts generated during the photochemical evolution of PAH-containing interstellar ice analogs as part of an ongoing collaboration with researchers at the Astrochemistry Lab at NASA Ames.

  10. Detection of polycyclic aromatic hydrocarbons in the shed skins of corn snakes (Elaphe guttata).

    PubMed

    Jones, D E; Magnin-Bissel, G; Holladay, S D

    2009-10-01

    Previous work has shown that organochlorine compounds, including chlordane, lindane and polychlorinated biphenyls, and heavy metals, including lead, mercury and cadmium, are readily detected in the shed skins of snakes dosed with these toxicants. This suggested the shed skins may have broad utility as a non-lethal biomarker tissue for environmental contamination. In the present study, two polycyclic aromatic hydrocarbons (PAHs), benzo[a]pyrene (B[a]P) and 3-methylcholanthrene (3-MC), were similarly studied, as representatives of a third major pollutant category of environmental concern. Both compounds were again readily detected in shed snake skins. These collective results suggest considerable environmental contamination information might be obtained from the evaluation of field-collected shed skins. An advantage of such evaluation is that capture, handling or sacrifice of the live animals is not required. PMID:19631985

  11. A model of the fate of polycyclic aromatic hydrocarbons in the Saguenay Fjord, Canada

    SciTech Connect

    Lun, R. [Univ. of Toronto, Ontario (Canada). Dept. of Chemical Engineering and Applied Chemistry; Lee, K. [Dept. of Fisheries and Oceans, Mont-Joli, Quebec (Canada). Inst. Maurice Lamontagne; Marco, L. de; Nalewajko, C. [Univ. of Toronto, Scarborough, Ontario (Canada). Dept. of Botany; Mackay, D. [Univ. of Toronto, Ontario (Canada). Dept. of Chemical Engineering and Applied Chemistry]|[Trent Univ., Peterborough, Ontario (Canada). Environmental Modeling Centre

    1998-02-01

    A comprehensive mass balance model is described that simulates the fate of polycyclic aromatic hydrocarbons (PAHs) in the Saguenay Fjord in eastern Quebec, Canada. The receiving environment is segmented into five compartments that are connected by upstream and downstream flows. Each segment consists of a layer of surficial sediment and a water column exposed to the atmosphere. The steady state model provides a method by which defined loadings of PAHs from the atmosphere and industrial sources are combined with other input parameters such as advective flow and atmospheric deposition rates to deduce quantities, concentrations, and transport and transformation rates. Results are presented for naphthalene, phenanthrene, and benzo[a]pyrene. The overall environmental pathways and simulation results are discussed. The simulated concentrations of benzo[a]pyrene in the sediment ranged from 100 to 315 ng/g, which are in good agreement with reported measurements.

  12. Accumulation of polycyclic aromatic hydrocarbons by lichen transplants: Comparison with gas-phase passive air samplers.

    PubMed

    Loppi, S; Pozo, K; Estellano, V H; Corsolini, S; Sardella, G; Paoli, L

    2015-09-01

    This study compared the accumulation of 16 polycyclic aromatic hydrocarbons (PAHs) in samples of the lichen Evernia prunastri exposed for 3months in and around an industrial area of S Italy with that in co-located passive gas-phase air samplers. The results showed a strong linear correlations (R=0.96, P<0.05) between total PAHs in lichens and in passive samplers, clearly indicating that lichen transplants may provide direct quantitative information on the atmospheric load by total PAHs, allowing translation of lichen values into atmospheric concentrations. To the best of our knowledge this is the first study reporting such a correlation with gas-phase passive air samplers. PMID:25911045

  13. Air pollution from a large steel factory: polycyclic aromatic hydrocarbon emissions from coke-oven batteries

    SciTech Connect

    Lorenzo Liberti; Michele Notarnicola; Roberto Primerano; Paolo Zannetti [Technical University of Bari, Bari (Italy). Department of Environmental Engineering and Sustainable Development

    2006-03-15

    A systematic investigation of solid and gaseous atmospheric emissions from some coke-oven batteries of one of Europe's largest integrated steel factory (Taranto, Italy) has been carried out. These emissions, predominantly diffuse, originate from oven leakages, as well as from cyclic operations of coal loading and coke unloading. In air monitoring samples, polycyclic aromatic hydrocarbons (PAHs) were consistently detected at concentrations largely exceeding threshold limit values. By means of PAHs speciation profile and benzo-(a)pyrene (BaP) equivalent dispersion modeling from diffuse sources, the study indicated that serious health risks exist not only in working areas, but also in a densely populated residential district near the factory. 30 refs., 5 figs., 3 tabs.

  14. Tenax as sorption sink for in vitro bioaccessibility measurement of polycyclic aromatic hydrocarbons in soils.

    PubMed

    Li, Chao; Cui, Xin Yi; Fan, Ying Ying; Teng, Ying; Nan, Zhong Ren; Ma, Lena Q

    2015-01-01

    Physiologically based in vitro methods have been developed to measure bioaccessibility of organic contaminants in soils. However, bioaccessibility of hydrophobic organic contaminants (HOCs) can be underestimated by in vitro tests if gastrointestinal (GI) solution fails to provide sufficient sorption sink for HOCs. To circumvent this drawback, Tenax was included in GI solution as sorption sink to trap mobilized HOCs and maintain the desorption gradient between soil and GI solution. Polycyclic aromatic hydrocarbons (PAHs) were selected as target HOCs, and physiologically based extraction test (PBET) was selected as the in vitro method. Inclusion of Tenax in GI solution increased bioaccessibility of PAHs in five spiked soils from 8.25-20.8% to 55.7-65.9% and the bioaccessibility of PAHs in a field contaminated soil from 3.70-6.92% to 16.3-31.0%. Our results demonstrated the effectiveness of Tenax as sorption sink to enhance PAH mobilization in bioaccessibility measurement in soils. PMID:25299793

  15. Formation of H2 from internally heated polycyclic aromatic hydrocarbons: Excitation energy dependence

    NASA Astrophysics Data System (ADS)

    Chen, T.; Gatchell, M.; Stockett, M. H.; Delaunay, R.; Domaracka, A.; Micelotta, E. R.; Tielens, A. G. G. M.; Rousseau, P.; Adoui, L.; Huber, B. A.; Schmidt, H. T.; Cederquist, H.; Zettergren, H.

    2015-04-01

    We have investigated the effectiveness of molecular hydrogen (H2) formation from Polycyclic Aromatic Hydrocarbons (PAHs) which are internally heated by collisions with keV ions. The present and earlier experimental results are analyzed in view of molecular structure calculations and a simple collision model. We estimate that H2 formation becomes important for internal PAH temperatures exceeding about 2200 K, regardless of the PAH size and the excitation agent. This suggests that keV ions may effectively induce such reactions, while they are unlikely due to, e.g., absorption of single photons with energies below the Lyman limit. The present analysis also suggests that H2 emission is correlated with multi-fragmentation processes, which means that the [PAH-2H]+ peak intensities in the mass spectra may not be used for estimating H2-formation rates.

  16. MOLECULAR HYDROGEN FORMATION CATALYZED BY POLYCYCLIC AROMATIC HYDROCARBONS IN THE INTERSTELLAR MEDIUM

    SciTech Connect

    Le Page, Valery; Snow, Theodore P.; Bierbaum, Veronica M. [Center for Astrophysics and Space Astronomy, University of Colorado, Boulder CO 80309 (United States)

    2009-10-10

    We present an alternate model for the formation of molecular hydrogen in the interstellar medium (ISM) where polycyclic aromatic hydrocarbon (PAH) cations may play a key role as catalysts. The mechanism involves the chemical trapping of H atoms on the periphery of the PAH carbon skeleton and the subsequent release of H{sub 2} through dissociative recombination of the hydrogenated ion with an electron. The estimated rate coefficient of H{sub 2} production using this process compares well with a widely accepted value of 3 x 10{sup -17} cm{sup 3} s{sup -1} for H{sub 2} formation on grains in the diffuse ISM. It is inferred that PAHs can contribute significantly to the formation of molecular hydrogen, especially in environments where the classical process of H adsorption on grains is impeded by high UV fluxes as in diffuse clouds and photon-dominated regions.

  17. Photocatalytic degradation-excitation-emission matrix fluorescence for increasing the selectivity of polycyclic aromatic hydrocarbon analyses.

    PubMed

    Kim, Yoon-Chang; Jordan, James A; Nahorniak, Michelle L; Booksh, Karl S

    2005-12-01

    The application of photocatalysis enhancement to calibration of fluorescence excitation-emission matrixes (EEMs) with parallel factor (PARAFAC) analysis is described. In this study, three- and four-way PARAFAC analysis was employed to extract the fluorescent species' spectra from overlapping EEMs. Time-dependent photocatalysis degradation of the polycyclic aromatic hydrocarbons (PAHs) was employed to create an additional dimension for analysis. The consequent four-dimension degradation-EEM data cubes have greater selectivity for each PAH than do three-dimension EEM data cubes alone. On a scale of 0 to 1, with 0 being completely collinear spectra and 1 being orthogonal spectra, including the time-dependent measurements increased the selectivity an average of 21%, from 0.73 to 0.87. PMID:16316176

  18. Cost of Developmental Delay from Prenatal Exposure to Airborne Polycyclic Aromatic Hydrocarbons

    PubMed Central

    Weiland, Katherine; Neidell, Matthew; Rauh, Virginia; Perera, Frederica

    2013-01-01

    Early life exposure to ambient polycyclic aromatic hydrocarbons (PAHs) can result in developmental delay. The negative health effects of PAHs have been well-documented but the cost of developmental delay due to PAH exposure has not been studied. The Columbia Center for Children’s Environmental Health previously has reported the significant effect of prenatal exposure to ambient PAHs on delayed mental development at three years, using the Bayley Scales in a cohort of low-income women and children in New York City (NYC). Here we have used the cohort results to estimate the annual costs of preschool special education services for low-income NYC children with developmental delay due to PAH exposure using the Environmentally Attributable Fraction method. The estimated cost of PAH-exposure-related services is over $13.7 million per year for Medicaid births in NYC. This high cost supports policies to reduce level of PAHs in NYC air. PMID:21317525

  19. Aromatic hydrocarbons associated with brines from geopressured wells. Annual report, fiscal 1985

    SciTech Connect

    Keeley, D.F.; Meriwether, J.R.

    1985-01-01

    Samples of cryocondensates - materials condensed at - 78.5/sup 0/C were taken on a regular basis from the gas stream for the USDOE geopressured wells. Most of the data has been taken from the Gladys McCall well as it has flowed on a regular and almost continous basis. The cryocondensates, not the ''condensate'' from gas wells, are almost exclusively aromatic hydrocarbons, primarily benzene, toluene, ethylbenzene, and the xylenes, but contain over 95 compounds, characterized using gas chromatographic-mass spectroscopy. The solubility in water and brine of benezene, toluene, ethylbenzene and o-xylene, some of the components of the cryocondensate, as well as distribution coefficients between water or brine and a standard oil have been measured. 25 refs.

  20. Source diagnostics of polycyclic aromatic hydrocarbons in urban road runoff, dust, rain and canopy throughfall.

    PubMed

    Zhang, Wei; Zhang, Shucai; Wan, Chao; Yue, Dapan; Ye, Youbin; Wang, Xuejun

    2008-06-01

    Diagnostic ratios and multivariate analysis were utilized to apportion polycyclic aromatic hydrocarbon (PAH) sources for road runoff, road dust, rain and canopy throughfall based on samples collected in an urban area of Beijing, China. Three sampling sites representing vehicle lane, bicycle lane and branch road were selected. For road runoff and road dust, vehicular emission and coal combustion were identified as major sources, and the source contributions varied among the sampling sites. For rain, three principal components were apportioned representing coal/oil combustion (54%), vehicular emission (34%) and coking (12%). For canopy throughfall, vehicular emission (56%), coal combustion (30%) and oil combustion (14%) were identified as major sources. Overall, the PAH's source for road runoff mainly reflected that for road dust. Despite site-specific sources, the findings at the study area provided a general picture of PAHs sources for the road runoff system in urban area of Beijing. PMID:17949873