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Sample records for pahs mixtures resolution

  1. Analysis of Polycyclic Aromatic Hydrocarbon (PAH Mixtures Using Diffusion-Ordered NMR Spectroscopy and Adsorption by Powdered Activated Carbon and Biochar

    Directory of Open Access Journals (Sweden)

    Dong An

    2018-03-01

    Full Text Available Analysis of polycyclic aromatic hydrocarbons (PAHs in air and water sources is a key part of environmental chemistry research, since most PAHs are well known to be associated with negative health impacts on humans. This study explores an approach for analyzing PAH mixtures with advanced nuclear magnetic resonance (NMR spectroscopic techniques including high-resolution one-dimensional (1D NMR spectroscopy and diffusion-ordered NMR spectroscopy (DOSY NMR. With this method, different kinds of PAHs can be detected and differentiated from a mixture with high resolution. The adsorption process of PAH mixtures by PAC and biochar was studied to understand the mechanism and assess the method.

  2. Dermal tumorigen PAH and complex mixtures for biological research

    International Nuclear Information System (INIS)

    Griest, W.H.; Guerin, M.R.; Ho, C.

    1985-01-01

    Thirteen commercially available, commonly reported four-five ring dermal tumorigen PAHs, were determined in a set of complex mixtures consisting of crude and upgraded coal liquids, and petroleum crude oils and their distillate fractions. Semi-preparative scale, normal phase high performance liquid chromatographic fractionation followed by capillary column gas chromatography or gas chromatography-mass spectroscopy were used for the measurements. Deuterated or carbon-14 labeled PAH served as internal standards or allowed recovery corrections. Approaches for the preparation and measurement of radiolabeled PAH were examined to provide chemical probes for biological study. Synthetic routes for production of 14 C labeled dihydrobenzo[a]pyrene and 14 C- or 3 H 10-azabenzo[a]pyrene are being studied to provide tracers for fundamental studies in tracheal transplant and skin penetration systems. (DT)

  3. Accumulation of metabolites during bacterial degradation of PAH-mixtures

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    Vila, J.; Lopez, Z.; Bauza, J.I. [Universitat de Barcelona (Spain). Department de Microbiologia; Minguillon, C. [Parc Cientific de Barcelona (ES). Institut de Recerca de Barcelona (IRB-PCB); Grifoll, M.

    2003-07-01

    In a previous work we identified a number of metabolites accumulated during growth in pyrene by Mycobacterium sp. AP1, and proposed a metabolic pathway for pyrene utilization. In order to confirm and complete this pathway we have isolated and identified the pyrene-degrading strains Mycobacterium sp. PGP2, CP1 and CP2. During growth on pyrene, strains AP1, PGP2, CP1 and CP2 accumulated 4,5-cis-pyrene-dihydrodiol, 4,5-phenanthrene dicarboxylic acid, 4-phenanthrene carboxylic acid, 3,4-dihydroxy-3-hydrophenanthrene-4-carboxylic acid, phthalic acid, and 6,6'-dihydroxy-2,2'-biphenyl dicarboxylic acid. Strains AP1, PGP2, CP1 and CP2 also grew on fluoranthene accumulating acenaphthenone, naphthalene-1,8-dicarboxylic acid, 9-fluorenone-1-carboxylic acid, Z-9-carboxymethylenefluorene-1-carboxylic acid and benzene-1,2,3-tricarboxylic acid. Similar metabolites were produced during growth onf fluoranthene by the Gram-positive strains CFt2 and CFt6, isolated by their capability of using this PAH as a sole source of carbon and energy. These fluoranthene-degrading strains also accumulated cis-1,9a-dihydroxy-1-hydrofluorene-9-one-8-carboxylic acid. In addition to pyrene and fluoranthene, all pyrene-degrading utilized phenanthrene as a sole source of carbon and energy, while the fluoranthene-degrading strains were unable to utilize pyrene or phenanthrene. Mycobacterium sp. AP1 acted on a wide range of PAHs, accumulating aromatic dicarboxylic acids, hydroxyacids, and ketones resulting from dioxygenation and ortho-cleavage, dioxygenation and meta-cleavage, and monooxygenation reactions. In cultures of strains AP1 and CP1 with a defined PAH-mixture only 20% removal of the parent compounds was observed. Analysis of acidic extracts showed the accumulation of the anticipated aromatic acids, suggesting that accumulation of acidic compounds could prevent further degradation of the mixture. Those results led us to isolation of strains DF11 and OH3, able to grow on the selected

  4. Mechanism-Based Classification of PAH Mixtures to Predict Carcinogenic Potential.

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    Tilton, Susan C; Siddens, Lisbeth K; Krueger, Sharon K; Larkin, Andrew J; Löhr, Christiane V; Williams, David E; Baird, William M; Waters, Katrina M

    2015-07-01

    We have previously shown that relative potency factors and DNA adduct measurements are inadequate for predicting carcinogenicity of certain polycyclic aromatic hydrocarbons (PAHs) and PAH mixtures, particularly those that function through alternate pathways or exhibit greater promotional activity compared to benzo[a]pyrene (BaP). Therefore, we developed a pathway-based approach for classification of tumor outcome after dermal exposure to PAH/mixtures. FVB/N mice were exposed to dibenzo[def,p]chrysene (DBC), BaP, or environmental PAH mixtures (Mix 1-3) following a 2-stage initiation/promotion skin tumor protocol. Resulting tumor incidence could be categorized by carcinogenic potency as DBC > BaP = Mix2 = Mix3 > Mix1 = Control, based on statistical significance. Gene expression profiles measured in skin of mice collected 12 h post-initiation were compared with tumor outcome for identification of short-term bioactivity profiles. A Bayesian integration model was utilized to identify biological pathways predictive of PAH carcinogenic potential during initiation. Integration of probability matrices from four enriched pathways (P PAH mixtures. These data further provide a 'source-to-outcome' model that could be used to predict PAH interactions during tumorigenesis and provide an example of how mode-of-action-based risk assessment could be employed for environmental PAH mixtures. © The Author 2015. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

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

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

    2014-12-01

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

  6. Persistent activation of DNA damage signaling in response to complex mixtures of PAHs in air particulate matter

    Energy Technology Data Exchange (ETDEWEB)

    Jarvis, Ian W.H., E-mail: Ian.Jarvis@ki.se [Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-171 77 Stockholm (Sweden); Bergvall, Christoffer, E-mail: Christoffer.Bergvall@anchem.su.se [Department of Analytical Chemistry, Stockholm University, Svante Arrhenius väg 16, SE-106 91 Stockholm (Sweden); Bottai, Matteo, E-mail: Matteo.Bottai@ki.se [Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-171 77 Stockholm (Sweden); Westerholm, Roger, E-mail: Roger.Westerholm@anchem.su.se [Department of Analytical Chemistry, Stockholm University, Svante Arrhenius väg 16, SE-106 91 Stockholm (Sweden); Stenius, Ulla, E-mail: Ulla.Stenius@ki.se [Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-171 77 Stockholm (Sweden); Dreij, Kristian, E-mail: Kristian.Dreij@ki.se [Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-171 77 Stockholm (Sweden)

    2013-02-01

    Complex mixtures of polycyclic aromatic hydrocarbons (PAHs) are present in air particulate matter (PM) and have been associated with many adverse human health effects including cancer and respiratory disease. However, due to their complexity, the risk of exposure to mixtures is difficult to estimate. In the present study the effects of binary mixtures of benzo[a]pyrene (BP) and dibenzo[a,l]pyrene (DBP) and complex mixtures of PAHs in urban air PM extracts on DNA damage signaling was investigated. Applying a statistical model to the data we observed a more than additive response for binary mixtures of BP and DBP on activation of DNA damage signaling. Persistent activation of checkpoint kinase 1 (Chk1) was observed at significantly lower BP equivalent concentrations in air PM extracts than BP alone. Activation of DNA damage signaling was also more persistent in air PM fractions containing PAHs with more than four aromatic rings suggesting larger PAHs contribute a greater risk to human health. Altogether our data suggests that human health risk assessment based on additivity such as toxicity equivalency factor scales may significantly underestimate the risk of exposure to complex mixtures of PAHs. The data confirms our previous findings with PAH-contaminated soil (Niziolek-Kierecka et al., 2012) and suggests a possible role for Chk1 Ser317 phosphorylation as a biological marker for future analyses of complex mixtures of PAHs. -- Highlights: ► Benzo[a]pyrene (BP), dibenzo[a,l]pyrene (DBP) and air PM PAH extracts were compared. ► Binary mixture of BP and DBP induced a more than additive DNA damage response. ► Air PM PAH extracts were more potent than toxicity equivalency factor estimates. ► Larger PAHs (> 4 rings) contribute more to the genotoxicity of PAHs in air PM. ► Chk1 is a sensitive marker for persistent activation of DNA damage signaling from PAH mixtures.

  7. Persistent activation of DNA damage signaling in response to complex mixtures of PAHs in air particulate matter

    International Nuclear Information System (INIS)

    Jarvis, Ian W.H.; Bergvall, Christoffer; Bottai, Matteo; Westerholm, Roger; Stenius, Ulla; Dreij, Kristian

    2013-01-01

    Complex mixtures of polycyclic aromatic hydrocarbons (PAHs) are present in air particulate matter (PM) and have been associated with many adverse human health effects including cancer and respiratory disease. However, due to their complexity, the risk of exposure to mixtures is difficult to estimate. In the present study the effects of binary mixtures of benzo[a]pyrene (BP) and dibenzo[a,l]pyrene (DBP) and complex mixtures of PAHs in urban air PM extracts on DNA damage signaling was investigated. Applying a statistical model to the data we observed a more than additive response for binary mixtures of BP and DBP on activation of DNA damage signaling. Persistent activation of checkpoint kinase 1 (Chk1) was observed at significantly lower BP equivalent concentrations in air PM extracts than BP alone. Activation of DNA damage signaling was also more persistent in air PM fractions containing PAHs with more than four aromatic rings suggesting larger PAHs contribute a greater risk to human health. Altogether our data suggests that human health risk assessment based on additivity such as toxicity equivalency factor scales may significantly underestimate the risk of exposure to complex mixtures of PAHs. The data confirms our previous findings with PAH-contaminated soil (Niziolek-Kierecka et al., 2012) and suggests a possible role for Chk1 Ser317 phosphorylation as a biological marker for future analyses of complex mixtures of PAHs. -- Highlights: ► Benzo[a]pyrene (BP), dibenzo[a,l]pyrene (DBP) and air PM PAH extracts were compared. ► Binary mixture of BP and DBP induced a more than additive DNA damage response. ► Air PM PAH extracts were more potent than toxicity equivalency factor estimates. ► Larger PAHs (> 4 rings) contribute more to the genotoxicity of PAHs in air PM. ► Chk1 is a sensitive marker for persistent activation of DNA damage signaling from PAH mixtures.

  8. Developmental exposure to a complex PAH mixture causes persistent behavioral effects in naive Fundulus heteroclitus (killifish) but not in a population of PAH-adapted killifish.

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    Brown, D R; Bailey, J M; Oliveri, A N; Levin, E D; Di Giulio, R T

    2016-01-01

    Acute exposures to some individual polycyclic aromatic hydrocarbons (PAHs) and complex PAH mixtures are known to cause cardiac malformations and edema in the developing fish embryo. However, the heart is not the only organ impacted by developmental PAH exposure. The developing brain is also affected, resulting in lasting behavioral dysfunction. While acute exposures to some PAHs are teratogenically lethal in fish, little is known about the later life consequences of early life, lower dose subteratogenic PAH exposures. We sought to determine and characterize the long-term behavioral consequences of subteratogenic developmental PAH mixture exposure in both naive killifish and PAH-adapted killifish using sediment pore water derived from the Atlantic Wood Industries Superfund Site. Killifish offspring were embryonically treated with two low-level PAH mixture dilutions of Elizabeth River sediment extract (ERSE) (TPAH 5.04 μg/L and 50.4 μg/L) at 24h post fertilization. Following exposure, killifish were raised to larval, juvenile, and adult life stages and subjected to a series of behavioral tests including: a locomotor activity test (4 days post-hatch), a sensorimotor response tap/habituation test (3 months post hatch), and a novel tank diving and exploration test (3months post hatch). Killifish were also monitored for survival at 1, 2, and 5 months over 5-month rearing period. Developmental PAH exposure caused short-term as well as persistent behavioral impairments in naive killifish. In contrast, the PAH-adapted killifish did not show behavioral alterations following PAH exposure. PAH mixture exposure caused increased mortality in reference killifish over time; yet, the PAH-adapted killifish, while demonstrating long-term rearing mortality, had no significant changes in mortality associated with ERSE exposure. This study demonstrated that early embryonic exposure to PAH-contaminated sediment pore water caused long-term locomotor and behavioral alterations in

  9. Quantification of PAHs and oxy-PAHs on airborne particulate matter in Chiang Mai, Thailand, using gas chromatography high resolution mass spectrometry

    Science.gov (United States)

    Walgraeve, Christophe; Chantara, Somporn; Sopajaree, Khajornsak; De Wispelaere, Patrick; Demeestere, Kristof; Van Langenhove, Herman

    2015-04-01

    An analytical method using gas chromatography high resolution mass spectrometry was developed for the determination of 16 polycyclic aromatic hydrocarbons (PAHs) and 12 oxygenated PAHs (of which 4 diketones, 3 ketones, 4 aldehydes and one anhydride) on atmospheric particulate matter with an aerodynamic diameter less than 10 μm (PM10). The magnetic sector mass spectrometer was run in multiple ion detection mode (MID) with a mass resolution above 10 000 (10% valley definition) and allows for a selective accurate mass detection of the characteristic ions of the target analytes. Instrumental detection limits between 0.04 pg and 1.34 pg were obtained for the PAHs, whereas for the oxy-PAHs they ranged between 0.08 pg and 2.13 pg. Pressurized liquid extraction using dichloromethane was evaluated and excellent recoveries ranging between 87% and 98% for the PAHs and between 74% and 110% for 10 oxy-PAHs were obtained, when the optimum extraction temperature of 150 °C was applied. The developed method was finally used to determine PAHs and oxy-PAHs concentration levels from particulate matter samples collected in the wet season at 4 different locations in Chiang Mai, Thailand (n = 72). This study brings forward the first concentration levels of oxy-PAHs in Thailand. The median of the sum of the PAHs and oxy-PAHs concentrations was 3.4 ng/m3 and 1.1 ng/m3 respectively, which shows the importance of the group of the oxy-PAHs as PM10 constituents. High molecular weight PAHs contributed the most to the ∑PAHs. For example, benzo[ghi]perylene was responsible for 30-44% of the ∑PAHs. The highest contribution to ∑oxy-PAHs came from 1,8-napthalic anhydride (26-78%), followed by anthracene-9,10-dione (4-27%) and 7H-benzo[de]anthracene-7-one (6-26%). Indications of the degradation of PAHs and/or formation of oxy-PAHs were observed.

  10. Later life swimming performance and persistent heart damage following subteratogenic PAH mixture exposure in the Atlantic killifish (Fundulus heteroclitus).

    Science.gov (United States)

    Brown, Daniel R; Thompson, Jasmine; Chernick, Melissa; Hinton, David E; Di Giulio, Richard T

    2017-12-01

    High-level, acute exposures to individual polycyclic aromatic hydrocarbons (PAHs) and complex PAH mixtures result in cardiac abnormalities in developing fish embryos. Whereas acute PAH exposures can be developmentally lethal, little is known about the later life consequences of early life, lower level PAH exposures in survivors. A population of PAH-adapted Fundulus heteroclitus from the PAH-contaminated Superfund site, Atlantic Wood Industries, Elizabeth River, Portsmouth, Virginia, United States, is highly resistant to acute PAH cardiac teratogenicity. We sought to determine and characterize long-term swimming performance and cardiac histological alterations of a subteratogenic PAH mixture exposure in both reference killifish and PAH-adapted Atlantic Wood killifish embryos. Killifish from a relatively uncontaminated reference site, King's Creek, Virginia, United States, and Atlantic Wood killifish were treated with dilutions of Elizabeth River sediment extract at 24 h post fertilization (hpf). Two proven subteratogenic dilutions, 0.1 and 1.0% Elizabeth River sediment extract (total PAH 5.04 and 50.4 µg/L, respectively), were used for embryo exposures. Then, at 5-mo post hatching, killifish were subjected to a swim performance test. A separate subset of these individuals was processed for cardiac histological analysis. Unexposed King's Creek killifish significantly outperformed the unexposed Atlantic Wood killifish in swimming performance as measured by Ucrit (i.e., critical swimming speed). However, King's Creek killifish exposed to Elizabeth River sediment extract (both 0.1 and 1.0%) showed significant declines in Ucrit. Histological analysis revealed the presence of blood in the pericardium of King's Creek killifish. Although Atlantic Wood killifish showed baseline performance deficits relative to King's Creek killifish, their pericardial cavities were nearly free of blood and atrial and ventricular alterations. These findings may explain, in part, the

  11. Micellar Enhanced Ultrafiltration for the Removal of Polycyclic Aromatic Hydrocarbons (PAHs Mixtures in Underground Contaminated Water in Oman

    Directory of Open Access Journals (Sweden)

    Mohamed Aoudia

    2011-12-01

    Full Text Available In an attempt to analyze polycyclic aromatic hydrocarbons (PAHs in diesel contaminated underground water in Oman (Rustaq, Gas chromatography-Mass spectrometry was first used to determine the different concentrations in a standard mixture containing 16 PAHs. Retention time and calibration curves were obtained for all aromatic compounds and were used to identify a given analyte as well as its concentration in the contaminated underground water. Micellar enhanced ultrafiltration (MEUF was then used to treat standard aqueous solution of PAHs at low concentration (~ 1 ppb using an edible nonionic surfactant (Tween 80. The totality of the mixture components was completely rejected. Within the experimental detection limit (± 0.01 ppb, the residual PAH concentrations were less than 0.01 ppb in accord with the allowed concentrations in drinking water. Likewise, excellent rejections of PAHs in MEUF treatment of diesel contaminated underground water at an Omani site (Rustaq were observed. The concentration of PAHs was reduced to less than 0.01 ppb, the accepted limit for the most toxic member of the PAH group (benzo(apyrene.

  12. Development of a Relative Potency Factor (Rpf) Approach for Polycyclic Aromatic Hydrocarbon (PAH) Mixtures (External Review Draft)

    Science.gov (United States)

    EPA is conducting a peer review and public comment of the scientific basis supporting the human health hazard and dose-response assessment of polycyclic aromatic hydrocarbon (PAH) mixtures that when finalized will appear on the Integrated Risk Information System (IRIS) database. ...

  13. Effect of Substrate Character on Heterogeneous Ozone Reaction Rate with Individual PAHs and Their Reaction Mixtures

    Science.gov (United States)

    Holmen, B. A.; Stevens, T.

    2009-12-01

    Vehicle exhaust contains many unregulated chemical compounds that are harmful to human health and the natural environment, including polycyclic aromatic hydrocarbons (PAH), a class of organic compounds derived from fuel combustion that can be carcinogenic and mutagenic. PAHs have been quantified in vehicle-derived ultrafine particles (Dpsolid, reacting the samples with gas-phase ozone, and determining both PAH loss over time and products formed, using thermal-desorption gas chromatography / mass spectrometry (TD-GC/MS). The individual PAHs anthracene, phenanthrene, and fluorene, adsorbed to a QFF were also separately reacted with 0.4 ppm ozone. A volatilization control and the collection of volatilized PAHs using a Tenax-packed thermal desorption vial completed the mass balance and aided determination parent-product relationships. Heterogeneous reaction products analyzed directly without derivatization indicate the formation of 9,10-anthracenedione, 9H-fluoren-9-one, and (1,1’-biphenyl)-2,2’-dicarboxaldehyde from the reaction of ozone with the PAH mix on a QFF, but only 9,10-anthracenedione was detected for the diesel PM reaction. The implications of these results for aging of diesel particulate in urban environments will be discussed.

  14. Passive dosing of polycyclic aromatic hydrocarbon (PAH) mixtures to terrestrial springtails: Linking mixture toxicity to chemical activities, equilibrium lipid concentrations, and toxic units

    DEFF Research Database (Denmark)

    Schmidt, Stine Nørgaard; Holmstrup, Martin; Smith, Kilian E. C.

    2013-01-01

    treatments, containing the polycyclic aromatic hydrocarbons (PAHs) naphthalene, phenanthrene, and pyrene. Springtail lethality was then linked to sum chemical activities (∑a), sum equilibrium lipid concentrations (∑Clipid eq.), and sum toxic units (∑TU). In each case, the effects of all 12 mixture treatments...... could be fitted to one sigmoidal exposure-response relationship. The effective lethal chemical activity (La50) of 0.027 was well within the expected range for baseline toxicity of 0.01-0.1. Linking the effects to the lipid-based exposure parameter yielded an effective lethal concentration (LClipid eq...

  15. Passive dosing of polycyclic aromatic hydrocarbon (PAH) mixtures to terrestrial springtails: linking mixture toxicity to chemical activities, equilibrium lipid concentrations, and toxic units.

    Science.gov (United States)

    Schmidt, Stine N; Holmstrup, Martin; Smith, Kilian E C; Mayer, Philipp

    2013-07-02

    A 7-day mixture toxicity experiment with the terrestrial springtail Folsomia candida was conducted, and the effects were linked to three different mixture exposure parameters. Passive dosing from silicone was applied to tightly control exposure levels and compositions of 12 mixture treatments, containing the polycyclic aromatic hydrocarbons (PAHs) naphthalene, phenanthrene, and pyrene. Springtail lethality was then linked to sum chemical activities (∑a), sum equilibrium lipid concentrations (∑C(lipid eq.)), and sum toxic units (∑TU). In each case, the effects of all 12 mixture treatments could be fitted to one sigmoidal exposure-response relationship. The effective lethal chemical activity (La50) of 0.027 was well within the expected range for baseline toxicity of 0.01-0.1. Linking the effects to the lipid-based exposure parameter yielded an effective lethal concentration (LC(lipid eq 50)) of 133 mmol kg(-1) lipid in good correspondence with the lethal membrane burden for baseline toxicity (40-160 mmol kg(-1) lipid). Finally, the effective lethal toxic unit (LTU50) of 1.20 was rather close to the expected value of 1. Altogether, passive dosing provided tightly controlled mixture exposure in terms of both level and composition, while ∑a, ∑C(lipid eq.), and ∑TU allowed baseline toxicity to be linked to mixture exposure.

  16. Laboratory evaluation of PAH oxidation by magnesium peroxides and iron oxides mixtures as reactive material for groundwater remediation

    International Nuclear Information System (INIS)

    Valderrama, C.; Gamisans, X.; Cortina, J.L.; Farran, A.; Marti, V.

    2005-01-01

    Polycyclic Aromatic Hydrocarbons (PAHs) are a class of compounds consisting of two or more fused aromatic rings. They represent the largest group of compounds that are mutagenic, carcinogenic, and teratogenic and are included in the priority pollutants lists. In recent years, increasing attention has been drawn to PAH contamination in aquatic sediments. Biological aerobic degradation was earlier the promoted option to degrade PAH in soils and sediments; however this could be extended for decades. In this direction, addition of oxygen has been proposed as an effective way to speed up their degradation in contaminated soil or groundwater. This objective could be achieved either by adding oxygen releasing compounds or by using an oxygen pump. The latter option is not economically defensible due to the enormous power needed. The use of ex-situ technologies to treat contaminated soils is in general not effective due to the high costs and work efforts demanded to remove big quantities of soil. For that reason, the use of in-situ technologies based on degradation processes has been identified as a suitable approach. These technologies would reduce costs and environmental impacts due to reduction of soil transportations and digging activities. In-situ degradation of recalcitrant contaminants could be achieved by using strong oxidant agents by soil injection or by using permeable treatment wall or zones. Oxidants typically used have been hydrogen peroxide, potassium permanganate and ozone. In situ chemical oxidation using Fenton's reagent (hydrogen peroxide and iron(II) mixtures) has been evaluated for BTEX and poly-aromatic compounds. The successful application of in situ Fenton's reagent chemical oxidation is based on an understanding of oxidant chemistry and the geology, hydrogeology and chemistry of the contaminant site. Choosing the proper conditions requires the determination of 1) the better way to promote the formation of the OH radicals that react with the

  17. Effect-directed analysis and mixture effects of AhR-active PAHs in crude oil and coastal sediments contaminated by the Hebei Spirit oil spill

    International Nuclear Information System (INIS)

    Hong, Seongjin; Lee, Sangwoo; Choi, Kyungho; Kim, Gi Beum; Ha, Sung Yong; Kwon, Bong-Oh; Ryu, Jongseong; Yim, Un Hyuk; Shim, Won Joon; Jung, Jinho; Giesy, John P.; Khim, Jong Seong

    2015-01-01

    The major AhR-active PAHs were identified in crude oil and oil-contaminated sediments by use of effect-directed analysis. As part of the study, an enhanced potency balance analysis was conducted by establishing the novel relative potency values of (alkyl)-PAHs from the H4IIE-luc bioassay. Silica gel column fractionation of crude oil resulted in greater AhR-mediated potencies in fractions of aromatics (F2) and resins (F3), and such trend was also observed for field collected sediment samples. AhR-mediated potencies of six F2 sub-fractions from HPLC indicated that the majority of F2 responses were attributable to 3–4 ring aromatics. Target PAHs including C4-phenanthrene, C1-chrysene, and C3-chrysene in sediments explained ∼18% of the bioassay-derived TCDD-EQs, however, the unknown AhR agonists and potential mixture effects remain in question. Overall, the AhR-potency and antagonistic potential of residual oil in sediment tended to decrease over time, thus monitoring of weathering process would be key for the post management of oil-contaminated sites. - Highlights: • AhR-active PAHs in crude oil and sediments were newly determined using EDA. • Novel relative potency values of (alkyl)-PAHs for AhR activity were established. • Three to four ring PAHs were identified to be major AhR agonists in crude oil. • Parent and alkyl-PAHs explained ∼18% of the total AhR-mediated potencies of crude oil. • AhR-mediated potencies apparently decreased by the timely weathering processes. - “Major AhR agonists were identified three to four ring PAHs in crude oil and sediments determined by use of effect-directed analysis.”

  18. Novel Insight for Organic Matter Sourcing: Interest of Time Resolved Fluorescence to Qualify and Quantify PAH Content of Solid Matrix at High Resolution

    Science.gov (United States)

    Quiers, M.; Perrette, Y.; Jacq, K.; Pousset, E.; Plassart, G.

    2017-12-01

    OM fluorescence is today a well-developed tool used to characterize and quantify organic matter (OM), but also to evaluate and discriminate OM fate and changes related to climate and environmental modifications. While fluorescence measurements on water and soils extracts provide information about organic fluxes today, solid phase fluorescence using natural archives allows to obtain high resolution records of OM evolution during time. These evolutions can be discussed in regards of climate and environmental perturbations detected in archives using different proxies, and thus provide keys for understanding factors driving carbon fluxes mechanisms. Among fluorescent organic species, Polycyclic Aromatic Hydrocarbons (PAH) have been used as probe molecules for organic contamination tracking. Moreover, monitoring studies have shown that PAH could also be used as markers to discriminates atmospheric and erosion factors leading to PAH and organic matter fluxes to the aquifer. PAH records in soils and natural archives appear as a promising proxy to follow both past atmospheric contamination and soil erosion. But, PAH fluorescence is difficult to discriminate from bulk OM fluorescence using steady-state fluorescence (SSF) technics as their fluorescence domains recover. Time resolved emission spectroscopy (TRES) increases the information provided by SSF technic, adding a time dimension to measurements and allowing to discriminate PAH fluorescence. We report here a first application of this technic on natural archives. The challenge is to obtain TRES signature along the sample, including for low PAH concentrations. This study aims to evaluate the reliability of high resolution TRES measurement as PAH carbon fluxes sources. Method is based on LIF instrument for solid phase fluorescence measurement. An instrument coupling an excitation system constituting by 2 pulsed lasers (266 and 355 nm) and a detection system was developed. This measurement provides high resolution record of

  19. Biocatalytic Resolution of Enantiomeric Mixtures of 1-Aminoethanephosphonic Acid

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    Paweł Kafarski

    2011-07-01

    Full Text Available Several fungal strains, namely Bauveria bassiana, Cuninghamella echinulata, Aspergillus fumigatus, Penicillium crustosum and Cladosporium herbarum, were used as biocatalysts to resolve racemic mixtures of 1-aminoethanephosphonic acid using L/D amino acid oxidase activity. The course of reaction was analyzed by 31P-NMR in the presence of cyclodextrin used as chiral discriminating agent. The best result (42% e.e of R-isomer was obtained with a strain of Cuninghamella echinulata.

  20. Mixture

    Directory of Open Access Journals (Sweden)

    Silva-Aguilar Martín

    2011-01-01

    Full Text Available Metals are ubiquitous pollutants present as mixtures. In particular, mixture of arsenic-cadmium-lead is among the leading toxic agents detected in the environment. These metals have carcinogenic and cell-transforming potential. In this study, we used a two step cell transformation model, to determine the role of oxidative stress in transformation induced by a mixture of arsenic-cadmium-lead. Oxidative damage and antioxidant response were determined. Metal mixture treatment induces the increase of damage markers and the antioxidant response. Loss of cell viability and increased transforming potential were observed during the promotion phase. This finding correlated significantly with generation of reactive oxygen species. Cotreatment with N-acetyl-cysteine induces effect on the transforming capacity; while a diminution was found in initiation, in promotion phase a total block of the transforming capacity was observed. Our results suggest that oxidative stress generated by metal mixture plays an important role only in promotion phase promoting transforming capacity.

  1. Biogeochemical and isotopic gradients in a BTEX/PAH contaminant plume: Model-based interpretation of a high-resolution field data set

    DEFF Research Database (Denmark)

    Prommer, H.; Anneser, B.; Rolle, Massimo

    2009-01-01

    of toluene, which is the most rapidly degrading compound and the most important reductant at the site. The resulting depth profiles at the observation well show distinct differences between the small isotopic enrichment in the contaminant plume core and the much stronger enrichment of up to 3.3 parts per......A high spatial resolution data set documenting carbon and sulfur isotope fractionation at a tar oil-contaminated, sulfate-reducing field site was analyzed with a reactive transport model. Within a comprehensive numerical model, the study links the distinctive observed isotope depth profiles...... with the degradation of various monoaromatic and polycyclic aromatic hydrocarbon compounds (BTEX/PAHs) under sulfate-reducing conditions. In the numerical model, microbial dynamics were simulated explicitly and isotope fractionation was directly linked to the differential microbial uptake of lighter and heavier carbon...

  2. Pressure effect in the X-ray intrinsic position resolution in noble gases and mixtures

    CERN Document Server

    Azevedo, C.D.R.

    2016-12-13

    A study of the gas pressure effect in the position resolution of an interacting X- or gamma-ray photon in a gas medium is performed. The intrinsic position resolution for pure noble gases (Argon and Xenon) and their mixtures with CO2 and CH4 were calculated for several gas pressures (1-10bar) and for photon energies between 5.4 and 60.0 keV, being possible to establish a linear match between the intrinsic position resolution and the inverse of the gas pressure in that energy range. In order to evaluate the quality of the method here described, a comparison between the available experimental data and the calculated one in this work, is done and discussed. In the majority of the cases, a strong agreement is observed.

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

    International Nuclear Information System (INIS)

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

    2015-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-07-01

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

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

    International Nuclear Information System (INIS)

    Zhang, Yong; Kwok, Sun

    2015-01-01

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

  6. Crystallization-induced dynamic resolution R-epimer from 25-OCH3-PPD epimeric mixture.

    Science.gov (United States)

    Zhang, Sainan; Tang, Yun; Cao, Jiaqing; Zhao, Chen; Zhao, Yuqing

    2015-11-15

    25-OCH3-PPD is a promising antitumor dammarane sapogenin isolated from the total saponin-hydrolyzed extract of Panax ginseng berry and Panax notoginseng leaves. 20(R)-25-OCH3-PPD was more potent as an anti-cancer agent than 20(S)-25-OCH3-PPD and epimeric mixture of 25-OCH3-PPD. This paper describes the rapid separation process of the R-epimer of 25-OCH3-PPD from its epimeric mixture by crystallization-induced dynamic resolution (CIDR). The optimized CIDR process was based on single factor analysis and nine well-planned orthogonal design experiments (OA9 matrix). A rapid and sensitive reverse phase high-performance liquid chromatographic (HPLC) method with evaporative light-scattering detector (ELSD) was developed and validated for the quantitation of 25-OCH3-PPD epimeric mixture and crystalline product. Separation and quantitation were achieved with a silica column using a mobile phase consisting of methanol and water (87:13, v/v) at a flow rate of 1.0mL/min. The ELSD detection was performed at 50°C and 3L/min. Under conditions involving 3mL of 95% ethanol, 8% HCl, and a hermetically sealed environment for 72h, the maximum production of 25(R)-OCH3-PPD was achieved with a chemical purity of 97% and a total yield of 87% through the CIDR process. The 25(R)-OCH3-PPD was nearly completely separated from the 220mg 25-OCH3-PPD epimeric mixture. Overall, a simple and steady small-batch purification process for the large-scale production of 25(R)-OCH3-PPD from 25-OCH3-PPD epimeric mixture was developed. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Densities mixture unfolding for data obtained from detectors with finite resolution and limited acceptance

    Energy Technology Data Exchange (ETDEWEB)

    Gagunashvili, N.D., E-mail: nikolai@unak.is

    2015-04-01

    A procedure based on a Mixture Density Model for correcting experimental data for distortions due to finite resolution and limited detector acceptance is presented. Addressing the case that the solution is known to be non-negative, in the approach presented here, the true distribution is estimated by a weighted sum of probability density functions with positive weights and with the width of the densities acting as a regularization parameter responsible for the smoothness of the result. To obtain better smoothing in less populated regions, the width parameter is chosen inversely proportional to the square root of the estimated density. Furthermore, the non-negative garrote method is used to find the most economic representation of the solution. Cross-validation is employed to determine the optimal values of the resolution and garrote parameters. The proposed approach is directly applicable to multidimensional problems. Numerical examples in one and two dimensions are presented to illustrate the procedure.

  8. High resolution conductometry for isotopic assay of deuterium in mixtures of heavy water and light water

    International Nuclear Information System (INIS)

    Ananthanarayanan, R.; Sahoo, P.; Murali, N.

    2014-01-01

    A PC based high resolution conductivity monitoring technique has been deployed for determination of isotopic purity of heavy water in samples containing heavy water and light water mixtures using pulsating sensor based conductivity monitoring instrument. The technique involves accurate determination of conductivities of a series of specially treated heavy water and light water mixtures of various compositions at a constant solution temperature. The shift in conductivity (Δκ), which is the difference between conductivities of composite mixture after and before the formation of a typical complex compound (boric acid–mannitol complex in this case), shows a smooth and reproducible decreasing trend with increase in percentage composition of heavy water. This relation, which is obtained by appropriate calibration, is used in the software program for direct display of isotopic purity of heavy water. The technique is examined for determination of percentage composition of heavy water in the entire range of concentration (0-100 %) with reasonable precision (relative standard deviation, RSD ≤1.5 %). About 1 mL of sample is required for each analysis and analysis is completed within a couple of minutes after pretreatment of sample. The accuracy in measurement is ≤1.75 %. (author)

  9. 75 FR 8937 - Development of a Relative Potency Factor (RPF) Approach for Polycyclic Aromatic Hydrocarbon (PAH...

    Science.gov (United States)

    2010-02-26

    ... Relative Potency Factor (RPF) Approach for Polycyclic Aromatic Hydrocarbon (PAH) Mixtures AGENCY... Aromatic Hydrocarbon (PAH) Mixtures'' (EPA/635/R-08/012A). The draft document was prepared by the National... 27, 2010. The listening session on the draft document for PAH mixtures will be held on April 7, 2010...

  10. Unconventional signal detection techniques with Gaussian probability mixtures adaptation in non-AWGN channels: full resolution receiver

    Science.gov (United States)

    Chabdarov, Shamil M.; Nadeev, Adel F.; Chickrin, Dmitry E.; Faizullin, Rashid R.

    2011-04-01

    In this paper we discuss unconventional detection technique also known as «full resolution receiver». This receiver uses Gaussian probability mixtures for interference structure adaptation. Full resolution receiver is alternative to conventional matched filter receivers in the case of non-Gaussian interferences. For the DS-CDMA forward channel with presence of complex interferences sufficient performance increasing was shown.

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

    Science.gov (United States)

    Samburova, Vera; Zielinska, Barbara; Khlystov, Andrey

    2017-08-15

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

  12. Analytical resolution of the mixture TBP-HDBP-H2MBP-H3PO4

    International Nuclear Information System (INIS)

    Pires, M.A.F.

    1983-01-01

    Several schemes for the separation of dibutylphosphoric acid (HDBP), main degradation product of tributylphosphate (TBP), in TBP/diluent, TBP/diluent-uranyl nitrate and TBP/diluent-thorium nitrate mixture were studied. For the resolution of HDBP-TBP/diluent-heavy metal nitrates (U-VI,Th-IV) systems, techniques such as: in exchange chromatography, ion chromatography using common ion exchangers and chromatographic separation with alumina column were investigated. For the identification, determination and analytical resolution following up the several systems studied, techniques such as refraction index measurement, electrical conductivity measurement, molecular absorption spectrophotometry, gas chromatography and ion chromatography, were applied. The separation of HDBP component was achieved using an alumina column where it was adsorbed from the TBP/diluent-uranyl nitrate and selectively eluted. Several modifications of this procedure for samples from the Uranium Purification Pilot Plant at Instituto de Pesquisas Energeticas e Nucleares (Sao Paulo, Brazil) were made. Special emphasis was given to the determination of HDBP using the ion chromatography technique. HDBP along with any monobutylphosphate acid (H 2 MBP) and phosphoric acid (H 3 PO 4 ) were stripped from the organic phase into dilute sodium hydroxide. HDBP is separated from H 2 MBP and H 3 PO 4 by ion chromatography and determined by its peak height. The determination of degradation products from TBP in TBP/diluent-uranyl nitrate and TBP/diluent-thorium nitrate systems was then performed. The detection limit for dibutylphosphate is 1.0μg HDBP/ml of analyte solution. (Author) [pt

  13. PAHs in Translucent Interstellar Clouds

    Science.gov (United States)

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

    2011-05-01

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

  14. A PAH growth mechanism and synergistic effect on PAH formation in counterflow diffusion flames

    KAUST Repository

    Wang, Yu

    2013-09-01

    A reaction mechanism having molecular growth up to benzene for hydrocarbon fuels with up to four carbon-atoms was extended to include the formation and growth of polycyclic aromatic hydrocarbons (PAHs) up to coronene (C24H12). The new mechanism was tested for ethylene premixed flames at low (20torr) and atmospheric pressures by comparing experimentally observed species concentrations with those of the computed ones for small chemical species and PAHs. As compared to several existing mechanisms in the literature, the newly developed mechanism showed an appreciable improvement in the predicted profiles of PAHs. The new mechanism was also used to simulate PAH formation in counterflow diffusion flames of ethylene to study the effects of mixing propane and benzene in the fuel stream. In the ethylene-propane flames, existing experimental results showed a synergistic effect in PAH concentrations, i.e. PAH concentrations first increased and then decreased with increasing propane mixing. This PAH behavior was successfully captured by the new mechanism. The synergistic effect was predicted to be more pronounced for larger PAH molecules as compared to the smaller ones, which is in agreement with experimental observations. In the experimental study in which the fuel stream of ethylene-propane flames was doped with benzene, a synergistic effect was mitigated for benzene, but was observed for large PAHs. This effect was also predicted in the computed PAH profiles for these flames. To explain these responses of PAHs in the flames of mixture fuels, a pathway analysis has been conducted, which show that several resonantly stabilized species as well as C4H4 and H atom contribute to the enhanced synergistic behaviors of larger PAHs as compared to the small ones in the flames of mixture fuels. © 2013 The Combustion Institute.

  15. Genotoxicity but not the AhR-mediated activity of PAHs is inhibited by other components of complex mixtures of ambient air pollutants

    Czech Academy of Sciences Publication Activity Database

    Líbalová, Helena; Krčková, S.; Uhlířová, Kateřina; Milcová, Alena; Schmuczerová, Jana; Cigánek, M.; Kléma, J.; Machala, M.; Šrám, Radim; Topinka, Jan

    2014-01-01

    Roč. 225, č. 3 (2014), s. 350-357 ISSN 0378-4274 R&D Projects: GA ČR GAP503/11/0142 Institutional support: RVO:68378041 Keywords : air pollutin * DNA adducts * complex mixtures Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 3.262, year: 2014

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

    International Nuclear Information System (INIS)

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

    2009-01-01

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

  17. Phenylacetylene and PAH

    Indian Academy of Sciences (India)

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

  18. Improved Resolution of Hydrocarbon Structures and Constitutional Isomers in Complex Mixtures Using Gas Chromatography-Vacuum Ultraviolet-Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Isaacman, Gabriel [Univ. of California, Berkeley, CA (United States); Wilson, Kevin R. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chan, Arthur W. H. [Univ. of California, Berkeley, CA (United States); Worton, David R. [Univ. of California, Berkeley, CA (United States). Aerosol Dynamics Inc., Berkeley, CA (United States); Kimmel, Joel R. [Aerodyne Research, Inc., Billerica, MA (United States); Univ. of Colorado, Boulder, CO (United States). Tofwerk AG, Thun (Switzerland); Nah, Theodora [Univ. of California, Berkeley, CA (United States); Hohaus, Thorsten [Aerodyne Research, Inc., Billerica, MA (United States); Gonin, Marc [Tofwerk AG, Thun (Switzerland); Kroll, Jesse H. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Worsnop, Douglas R. [Aerodyne Research, Inc., Billerica, MA (United States); Goldstein, Allen H. [Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-01-30

    Understanding the composition of complex hydrocarbon mixtures is important for environmental studies in a variety of fields, but many prevalent compounds cannot be confidently identified using traditional gas chromatography/mass spectrometry (GC/MS) techniques. In this study, we use vacuum-ultraviolet (VUV) ionization to elucidate the structures of a traditionally “unresolved complex mixture” by separating components by GC retention time, tR, and mass-to-charge ratio, m/z, which are used to determine carbon number, NC, and the number of rings and double bonds, NDBE. Constitutional isomers are resolved on the basis of tR, enabling the most complete quantitative analysis to date of structural isomers in an environmentally relevant hydrocarbon mixture. Unknown compounds are classified in this work by carbon number, degree of saturation, presence of rings, and degree of branching, providing structural constraints. The capabilities of this analysis are explored using diesel fuel, in which constitutional isomer distribution patterns are shown to be reproducible between carbon numbers and follow predictable rules. Nearly half of the aliphatic hydrocarbon mass is shown to be branched, suggesting branching is more important in diesel fuel than previously shown. Lastly, the classification of unknown hydrocarbons and the resolution of constitutional isomers significantly improves resolution capabilities for any complex hydrocarbon mixture.

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

    International Nuclear Information System (INIS)

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

    1986-02-01

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

  20. Ga+ TOF-SIMS lineshape analysis for resolution enhancement of MALDI MS spectra of a peptide mixture

    International Nuclear Information System (INIS)

    Malyarenko, D.I.; Chen, H.; Wilkerson, A.L.; Tracy, E.R.; Cooke, W.E.; Manos, D.M.; Sasinowski, M.; Semmes, O.J.

    2004-01-01

    The use of mass spectrometry to obtain molecular profiles indicative of alteration of concentrations of peptides in body fluids is currently the subject of intense investigation. For surface-based time-of-flight mass spectrometry the reliability and specificity of such profiling methods depend both on the resolution of the measuring instrument and on the preparation of samples. The present work is a part of a program to use Ga + beam TOF-SIMS alone, and as an adjunct to MALDI, in the development of reliable protein and peptide markers for diseases. Here, we describe techniques to prepare samples of relatively high-mass peptides, which serve as calibration standards and proxies for biomarkers. These are: Arg8-vasopressin, human angiotensin II, and somatostatin. Their TOF-SIMS spectra show repeatable characteristic features, with mass resolution exceeding 2000, including parent peaks and chemical adducts. The lineshape analysis for high-resolution parent peaks is shown to be useful for filter construction and deconvolution of inferior resolution SELDI-TOF spectra of calibration peptide mixture

  1. Band-selective excited ultrahigh resolution PSYCHE-TOCSY: fast screening of organic molecules and complex mixtures.

    Science.gov (United States)

    Kakita, Veera Mohana Rao; Vemulapalli, Sahithya Phani Babu; Bharatam, Jagadeesh

    2016-04-01

    Precise assignments of (1) H atomic sites and establishment of their through-bond COSY or TOCSY connectivity are crucial for molecular structural characterization by using (1) H NMR spectroscopy. However, this exercise is often hampered by signal overlap, primarily because of (1) H-(1) H scalar coupling multiplets, even at typical high magnetic fields. The recent developments in homodecoupling strategies for effectively suppressing the coupling multiplets into nice singlets (pure-shift), particularly, Morris's advanced broadband pure-shift yielded by chirp excitation (PSYCHE) decoupling and ultrahigh resolution PSYCHE-TOCSY schemes, have shown new possibilities for unambiguous structural elucidation of complex organic molecules. The superior broadband PSYCHE-TOCSY exhibits enhanced performance over the earlier TOCSY methods, which however warrants prolonged experimental times due to the requirement of large number of dwell increments along the indirect dimension. Herein, we present fast and band-selective analog of the broadband PSYCHE-TOCSY, which is useful for analyzing complex organic molecules that exhibit characteristic yet crowded spectral regions. The simple pulse scheme relies on band-selective excitation (BSE) followed by PSYCHE homodecoupling in the indirect dimension. The BSE-PSYCHE-TOCSY has been exemplified for Estradiol and a complex carbohydrate mixture comprised of six constituents of closely comparable molecular weights. The experimental times are greatly reduced viz., ~20 fold for Estradiol and ~10 fold for carbohydrate mixture, with respect to the broadband PSYCHE-TOCSY. Furthermore, unlike the earlier homonuclear band-selective decoupling, the BSE-PSYCHE-decoupling provides fully decoupled pure-shift spectra for all the individual chemical sites within the excited band. The BSE-PSYCHE-TOCSY is expected to have significant potential for quick screening of complex organic molecules and mixtures at ultrahigh resolution. Copyright © 2015 John Wiley

  2. Application of High-Resolution Ultrasonic Spectroscopy for analysis of complex formulations. Compressibility of solutes and solute particles in liquid mixtures

    International Nuclear Information System (INIS)

    Buckin, V

    2012-01-01

    The paper describes key aspects of interpretation of compressibility of solutes in liquid mixtures obtained through high-resolution measurements of ultrasonic parameters. It examines the fundamental relationships between the characteristics of solutes and the contributions of solutes to compressibility of liquid mixtures expressed through apparent adiabatic compressibility of solutes, and adiabatic compressibility of solute particles. In addition, it analyses relationships between the adiabatic compressibility of solutes and the measured ultrasonic characteristics of mixtures. Especial attention is given to the effects of solvents on the measured adiabatic compressibility of solutes and on concentration increment of ultrasonic velocity of solutes in mixtures.

  3. Sensitive rapid analysis of iodine-labelled protein mixture on flat substrates with high spatial resolution

    International Nuclear Information System (INIS)

    Zanevskij, Yu.V.; Ivanov, A.B.; Movchan, S.A.; Peshekhonov, V.D.; Chan Dyk Tkhan'; Chernenko, S.P.; Kaminir, L.B.; Krejndlin, Eh.Ya.; Chernyj, A.A.

    1983-01-01

    Usability of rapid analysis by electrophoresis of the admixture of I 125 -labelled proteins on flat samples by means of URAN type installation developed using a multiwire proportional chamber is studied. The sensitivity of the method is better than 200 cpm/cm 2 and the spatial resolution is approximately 1 mm. The procedure of the rapid analysis is no longer than several tens of minutes

  4. A complementary mobile phase approach based on the peak count concept oriented to the full resolution of complex mixtures.

    Science.gov (United States)

    Ortín, A; Torres-Lapasió, J R; García-Álvarez-Coque, M C

    2011-08-26

    Situations of minimal resolution are often found in liquid chromatography, when samples that contain a large number of compounds, or highly similar in terms of structure and/or polarity, are analysed. This makes full resolution with a single separation condition (e.g., mobile phase, gradient or column) unfeasible. In this work, the optimisation of the resolution of such samples in reversed-phase liquid chromatography is approached using two or more isocratic mobile phases with a complementary resolution behaviour (complementary mobile phases, CMPs). Each mobile phase is dedicated to the separation of a group of compounds. The CMPs are selected in such a way that, when the separation is considered globally, all the compounds in the sample are satisfactorily resolved. The search of optimal CMPs can be carried out through a comprehensive examination of the mobile phases in a selected domain. The computation time of this search has been reported to be substantially reduced by application of a genetic algorithm with local search (LOGA). A much simpler approach is here described, which is accessible to non-experts in programming, and offers solutions of the same quality as LOGA, with a similar computation time. The approach makes a sequential search of CMPs based on the peak count concept, which is the number of peaks exceeding a pre-established resolution threshold. The new approach is described using as test sample a mixture of 30 probe compounds, 23 of them with an ionisable character, and the pH and organic solvent contents as experimental factors. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Chromatographic resolution of closely related species in pharmaceutical chemistry: dehalogenation impurities and mixtures of halogen isomers.

    Science.gov (United States)

    Regalado, Erik L; Zhuang, Ping; Chen, Yadan; Makarov, Alexey A; Schafer, Wes A; McGachy, Neil; Welch, Christopher J

    2014-01-07

    In recent years, the use of halogen-containing molecules has proliferated in the pharmaceutical industry, where the incorporation of halogens, especially fluorine, has become vitally important for blocking metabolism and enhancing the biological activity of pharmaceuticals. The chromatographic separation of halogen-containing pharmaceuticals from associated isomers or dehalogenation impurities can sometimes be quite difficult. In an attempt to identify the best current tools available for addressing this important problem, a survey of the suitability of four chromatographic method development platforms (ultra high-performance liquid chromatography (UHPLC), core shell HPLC, achiral supercritical fluid chromatography (SFC) and chiral SFC) for separating closely related mixtures of halogen-containing pharmaceuticals and their dehalogenated isosteres is described. Of the 132 column and mobile phase combinations examined for each mixture, a small subset of conditions were found to afford the best overall performance, with a single UHPLC method (2.1 × 50 mm, 1.9 μm Hypersil Gold PFP, acetonitrile/methanol based aqueous eluents containing either phosphoric or perchloric acid with 150 mM sodium perchlorate) affording excellent separation for all samples. Similarly, a survey of several families of closely related halogen-containing small molecules representing the diversity of impurities that can sometimes be found in purchased starting materials for synthesis revealed chiral SFC (Chiralcel OJ-3 and Chiralpak IB, isopropanol or ethanol with 25 mM isobutylamine/carbon dioxide) as well as the UHPLC (2.1 × 50 mm, 1.8 μm ZORBAX RRHD Eclipse Plus C18 and the Gold PFP, acetonitrile/methanol based aqueous eluents containing phosphoric acid) as preferred methods.

  6. Resolution of the mixture TBP-H2 MPB-HDB-PH3PO4

    International Nuclear Information System (INIS)

    Pires, M.A.F.; Abrao, A.

    1980-01-01

    Tributylphosphate (TBP) is presently the most used extractant for uranium, thorium and zirconium technologies, both for the purification of these elements from their concentrates and for the recovery of heavy metals in the reprocessing of irradiated fuels. Nevertheless, in the presence of phosphoric acid, some degradation products are formed, such as: di-n-butylphosphoric acid (HDBP), monobutylphosphoric ancd (H 2 MBP) and ortophosphoric acid. The accumulation of these degradation products in the organic phase of the liquid-liquid extraction processes is highly undesirable. In order to avoid this problem, the separation of the mixture HDBP, H 2 MBP and H 3 PO 4 in TBP-dilutent or TBP-diluent-uranyl, thorium of zirconyl nitrate was then studied. Several separation techniques were investigated: adsorption using a cationic resin saturated with U(VI), chromatogtraphy in macroporous polymers, chromatography in alumina columns. Refractive index and condutimetric measurements were carried out to follow up the separation processes. The best results were obtained in an alumina column. (C.L.B.) [pt

  7. Chemometrics resolution and quantification power evaluation: Application on pharmaceutical quaternary mixture of Paracetamol, Guaifenesin, Phenylephrine and p-aminophenol

    Science.gov (United States)

    Yehia, Ali M.; Mohamed, Heba M.

    2016-01-01

    Three advanced chemmometric-assisted spectrophotometric methods namely; Concentration Residuals Augmented Classical Least Squares (CRACLS), Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS) and Principal Component Analysis-Artificial Neural Networks (PCA-ANN) were developed, validated and benchmarked to PLS calibration; to resolve the severely overlapped spectra and simultaneously determine; Paracetamol (PAR), Guaifenesin (GUA) and Phenylephrine (PHE) in their ternary mixture and in presence of p-aminophenol (AP) the main degradation product and synthesis impurity of Paracetamol. The analytical performance of the proposed methods was described by percentage recoveries, root mean square error of calibration and standard error of prediction. The four multivariate calibration methods could be directly used without any preliminary separation step and successfully applied for pharmaceutical formulation analysis, showing no excipients' interference.

  8. Compositional effects on PAH and soot formation in counterflow diffusion flames of gasoline surrogate fuels

    KAUST Repository

    Park, Sungwoo

    2017-02-05

    Gasoline surrogate fuels are widely used to understand the fundamental combustion properties of complex refinery gasoline fuels. In this study, the compositional effects on polycyclic aromatic hydrocarbons (PAHs) and soot formation were investigated experimentally for gasoline surrogate mixtures comprising n-heptane, iso-octane, and toluene in counterflow diffusion flames. A comprehensive kinetic model for the gasoline surrogate mixtures was developed to accurately predict the fuel oxidation along with the formation of PAHs and soot in flames. This combined model was first tested against ignition delay times and laminar burning velocities data. The proposed model for the formation and growth of PAHs up to coronene (C24H12) was based on previous studies and was tested against existing and present new experimental data. Additionally, in the accompanied soot model, PAHs with sizes larger than (including) pyrene were used for the inception of soot particles, followed by particle coagulations and PAH condensation/chemical reactions on soot surfaces. The major pathways for the formation of PAHs were also identified for the surrogate mixtures. The model accurately captures the synergistic PAH formation characteristics observed experimentally for n-heptane/toluene and iso-octane/toluene binary mixtures. Furthermore, the present experimental and modeling results also elucidated different trends in the formation of larger PAHs and soot between binary n-heptane/iso-octane and ternary n-heptane/iso-octane/toluene mixtures. Propargyl radicals (C3H3) were shown to be important in the formation and growth of PAHs for n-heptane/iso-octane mixtures when the iso-octane concentration increased; however, reactions involving benzyl radicals (C6H5CH2) played a significant role in the formation of PAHs for n-heptane/iso-octane/toluene mixtures. These results indicated that the formation of PAHs and subsequently soot was strongly affected by the composition of gasoline surrogate mixtures.

  9. Compositional effects on PAH and soot formation in counterflow diffusion flames of gasoline surrogate fuels

    KAUST Repository

    Park, Sungwoo; Wang, Yu; Chung, Suk-Ho; Sarathy, Mani

    2017-01-01

    Gasoline surrogate fuels are widely used to understand the fundamental combustion properties of complex refinery gasoline fuels. In this study, the compositional effects on polycyclic aromatic hydrocarbons (PAHs) and soot formation were investigated experimentally for gasoline surrogate mixtures comprising n-heptane, iso-octane, and toluene in counterflow diffusion flames. A comprehensive kinetic model for the gasoline surrogate mixtures was developed to accurately predict the fuel oxidation along with the formation of PAHs and soot in flames. This combined model was first tested against ignition delay times and laminar burning velocities data. The proposed model for the formation and growth of PAHs up to coronene (C24H12) was based on previous studies and was tested against existing and present new experimental data. Additionally, in the accompanied soot model, PAHs with sizes larger than (including) pyrene were used for the inception of soot particles, followed by particle coagulations and PAH condensation/chemical reactions on soot surfaces. The major pathways for the formation of PAHs were also identified for the surrogate mixtures. The model accurately captures the synergistic PAH formation characteristics observed experimentally for n-heptane/toluene and iso-octane/toluene binary mixtures. Furthermore, the present experimental and modeling results also elucidated different trends in the formation of larger PAHs and soot between binary n-heptane/iso-octane and ternary n-heptane/iso-octane/toluene mixtures. Propargyl radicals (C3H3) were shown to be important in the formation and growth of PAHs for n-heptane/iso-octane mixtures when the iso-octane concentration increased; however, reactions involving benzyl radicals (C6H5CH2) played a significant role in the formation of PAHs for n-heptane/iso-octane/toluene mixtures. These results indicated that the formation of PAHs and subsequently soot was strongly affected by the composition of gasoline surrogate mixtures.

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

    International Nuclear Information System (INIS)

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

    2016-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-11-20

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

  12. Polycyclic aromatic hydrocarbons (PAHs) biodegradation potential and diversity of microbial consortia enriched from tsunami sediments in Miyagi, Japan

    Energy Technology Data Exchange (ETDEWEB)

    Bacosa, Hernando Pactao, E-mail: hernando.bacosa@utexas.edu [Graduate School of Environmental Studies, Tohoku University, Aoba 6-6-20, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Marine Science Institute, The University of Texas at Austin, 750 Channel View Drive, Port Aransas, TX 78373 (United States); Inoue, Chihiro [Graduate School of Environmental Studies, Tohoku University, Aoba 6-6-20, Aramaki, Aoba-ku, Sendai 980-8579 (Japan)

    2015-02-11

    Highlights: • Most bacterial consortia from tsunami sediment degraded PAH mixture and pyrene. • The consortia were dominated by known and unknown PAHs-degrading bacteria. • Dokdonella clone is a potential new species and PAH degrader from tsunami sediment. • PAH-RHDα is better than nidA gene for estimating pyrene-degraders in the consortia. • First report on the PAH degradation and PAH-degrading bacteria from tsunami sediment. - Abstract: The Great East Japan Earthquake caused tsunamis and resulted in widespread damage to human life and infrastructure. The disaster also resulted in contamination of the environment by chemicals such as polycyclic aromatic hydrocarbons (PAHs). This study was conducted to investigate the degradation potential and describe the PAH-degrading microbial communities from tsunami sediments in Miyagi, Japan. PAH-degrading bacteria were cultured by enrichment using PAH mixture or pyrene alone as carbon and energy sources. Among the ten consortia tested for PAH mixture, seven completely degraded fluorene and more than 95% of phenanthrene in 10 days, while only four consortia partially degraded pyrene. Six consortia partially degraded pyrene as a single substrate. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) revealed that each sample was dominated by unique microbial populations, regardless of sampling location. The consortia were dominated by known PAHs degraders including Sphingomonas, Pseudomonas, and Sphingobium; and previously unknown degraders such as Dokdonella and Luteimonas. A potentially novel and PAH-degrading Dokdonella was detected for the first time. PAH-ring hydroxylating dioxygenase (PAH-RHDα) gene was shown to be more effective than nidA in estimating pyrene-degrading bacteria in the enriched consortia. The consortia obtained in this study are potential candidates for remediation of PAHs contaminated soils.

  13. Polycyclic aromatic hydrocarbons (PAHs) biodegradation potential and diversity of microbial consortia enriched from tsunami sediments in Miyagi, Japan

    International Nuclear Information System (INIS)

    Bacosa, Hernando Pactao; Inoue, Chihiro

    2015-01-01

    Highlights: • Most bacterial consortia from tsunami sediment degraded PAH mixture and pyrene. • The consortia were dominated by known and unknown PAHs-degrading bacteria. • Dokdonella clone is a potential new species and PAH degrader from tsunami sediment. • PAH-RHDα is better than nidA gene for estimating pyrene-degraders in the consortia. • First report on the PAH degradation and PAH-degrading bacteria from tsunami sediment. - Abstract: The Great East Japan Earthquake caused tsunamis and resulted in widespread damage to human life and infrastructure. The disaster also resulted in contamination of the environment by chemicals such as polycyclic aromatic hydrocarbons (PAHs). This study was conducted to investigate the degradation potential and describe the PAH-degrading microbial communities from tsunami sediments in Miyagi, Japan. PAH-degrading bacteria were cultured by enrichment using PAH mixture or pyrene alone as carbon and energy sources. Among the ten consortia tested for PAH mixture, seven completely degraded fluorene and more than 95% of phenanthrene in 10 days, while only four consortia partially degraded pyrene. Six consortia partially degraded pyrene as a single substrate. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) revealed that each sample was dominated by unique microbial populations, regardless of sampling location. The consortia were dominated by known PAHs degraders including Sphingomonas, Pseudomonas, and Sphingobium; and previously unknown degraders such as Dokdonella and Luteimonas. A potentially novel and PAH-degrading Dokdonella was detected for the first time. PAH-ring hydroxylating dioxygenase (PAH-RHDα) gene was shown to be more effective than nidA in estimating pyrene-degrading bacteria in the enriched consortia. The consortia obtained in this study are potential candidates for remediation of PAHs contaminated soils

  14. PAH processing in space

    NARCIS (Netherlands)

    Micelotta, Elisabetta Rita

    2009-01-01

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

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

    Science.gov (United States)

    Boersma, Christiaan

    to extend and test the applicability of the PAH proxy (band strength ratio) calibrations we have developed that are based on a single object, the reflection nebula (RN) NGC7023, to, and within, a variety of objects, each representing different types of astronomical environments. Starting with the results for NGC7023, our initial focus will be placed on other RNe for which high-quality Spitzer spectral maps are available. After this, the focus will shift to Spitzer and ISO catalogs holding PAH spectra from different object types and extragalactic sources at different quality levels. We will first fit the astronomical spectra using the PAH spectra and tools in PAHdb, a database and toolset developed by the proposers and perfectly suited for dealing with large spectral data sets. This approach quantitatively breaks down the emission into the different subclasses, of, PAH size, charge, structure and composition. Following this, the data will be analyzed using the traditional, qualitative, proxy approach in which the PAH bands are isolated and their strengths measured. Combining the results of these two approaches enables us to test the validity of, and to quantitatively calibrate, the PAH proxies that have been traditionally used to probe astronomical environments, and make a quantitative link between PAH observables and local astrophysical conditions. Previous work on NGC7023 demonstrated the potential of this approach, and applying it to different object types at varying quality levels will establish whether his approach holds in general or if adjustments must be made to tackle the full range of PAH-emitting astronomical environments. In parallel, we will perform stability analysis on the fits; establish quality requirements for spectral resolution, spectral range, and signal-to-noise; and make uncertainty estimates for the derived parameters. This is of particular importance for extragalactic sources, as it will establish a data quality threshold.

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

    International Nuclear Information System (INIS)

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

    2011-01-01

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

  17. Polycyclic Aromatic Hydrocarbon (PAH Exposure and DNA Adduct Semi-Quantitation in Archived Human Tissues

    Directory of Open Access Journals (Sweden)

    M. Margaret Pratt

    2011-06-01

    Full Text Available Polycyclic aromatic hydrocarbons (PAHs are combustion products of organic materials, mixtures of which contain multiple known and probable human carcinogens. PAHs occur in indoor and outdoor air, as well as in char-broiled meats and fish. Human exposure to PAHs occurs by inhalation, ingestion and topical absorption, and subsequently formed metabolites are either rendered hydrophilic and excreted, or bioactivated and bound to cellular macromolecules. The formation of PAH-DNA adducts (DNA binding products, considered a necessary step in PAH-initiated carcinogenesis, has been widely studied in experimental models and has been documented in human tissues. This review describes immunohistochemistry (IHC studies, which reveal localization of PAH-DNA adducts in human tissues, and semi-quantify PAH-DNA adduct levels using the Automated Cellular Imaging System (ACIS. These studies have shown that PAH-DNA adducts concentrate in: basal and supra-basal epithelium of the esophagus, cervix and vulva; glandular epithelium of the prostate; and cytotrophoblast cells and syncitiotrophoblast knots of the placenta. The IHC photomicrographs reveal the ubiquitous nature of PAH-DNA adduct formation in human tissues as well as PAH-DNA adduct accumulation in specific, vulnerable, cell types. This semi-quantative method for PAH-DNA adduct measurement could potentially see widespread use in molecular epidemiology studies.

  18. Improved resolution of hydrocarbon structures and constitutional isomers in complex mixtures using Gas Chromatography-Vacuum Ultraviolet-Mass Spectrometry (GC-VUV-MS)

    Energy Technology Data Exchange (ETDEWEB)

    Aerosol Dynamics Inc; Aerodyne Research, Inc.,; Tofwerk AG, Thun; Isaacman, Gabriel; Wilson, Kevin R.; Chan, Arthur W. H.; Worton, David R.; Kimmel, Joel R.; Nah, Theodora; Hohaus, Thorsten; Gonin, Marc; Kroll, Jesse H.; Worsnop, Doug R.; Goldstein, Allen H.

    2011-09-13

    Understanding the composition of complex hydrocarbon mixtures is important for environmental studies in a variety of fields, but many prevalent compounds cannot be confidently identified using traditional gas chromatography-mass spectrometry (GC-MS) techniques. This work uses vacuum-ultraviolet (VUV) ionization to elucidate the structures of a traditionally"unresolved complex mixture" by separating components by GC retention time, tR, and mass-to-charge ratio, m/Q, which are used to determine carbon number, NC, and the number of rings and double bonds, NDBE. Constitutional isomers are resolved based on tR, enabling the most complete quantitative analysis to date of structural isomers in an environmentally-relevant hydrocarbon mixture. Unknown compounds are classified in this work by carbon number, degree of saturation, presence of rings, and degree of branching, providing structural constraints. The capabilities of this analysis are explored using diesel fuel, in which constitutional isomer distribution patterns are shown to be reproducible between carbon numbers and follow predictable rules. Nearly half of the aliphatic hydrocarbon mass is shown to be branched, suggesting branching is more important in diesel fuel than previously shown. The classification of unknown hydrocarbons and the resolution of constitutional isomers significantly improves resolution capabilities for any complex hydrocarbon mixture.

  19. The Diversity of PAH-degrading bacteria in a deep-sea water column above the Southwest Indian Ridge

    Directory of Open Access Journals (Sweden)

    Zongze eShao

    2015-08-01

    Full Text Available The bacteria involved in organic pollutant degradation in pelagic deep-sea environments are largely unknown. In this report, the diversity of polycyclic aromatic hydrocarbon ( PAH-degrading bacteria was analyzed in deep-sea water on the Southwest Indian Ridge (SWIR. After enrichment with a PAH mixture (phenanthrene, anthracene, fluoranthene and pyrene, 9 nine bacterial consortia were obtained from depths of 3946 m to 4746 m. PAH degradation occurred to all components of the mixture, but when using a single PAH as the sole carbon and energy source, only phenanthrene can be degraded obviously. This indicates the cometabolism of anthracene, fluoranthene and pyrene with phenanthreneWhile the consortia degraded all four PAHs when supplied in a mixture, when PAHs were tested individually, only phenanthrene supported growth. Thus, degradation of the PAH mixture reflected a cometabolism of anthracene, fluoranthene and pyrene with phenanthrene. Further, both culture-dependent and independent methods revealed many new bacteria involved in PAH degradation. Specifically, the alpha and gamma subclasses of Proteobacteria were confirmed as the major groups within the communities. Additionally, Actinobacteria, the CFB group and Firmicutes were detected. Denaturing Gradient Gel Electrophoresis (DGGE analysis showed that bacteria closely affiliated with Alcanivorax, Novosphingobium and Rhodovulum occurred most frequently in different PAH-degrading consortia. More than half of the isolates (34 of 51 isolates were confirmed to have the ability to grow with the PAH mixture By using general heterotrophic media, 51 bacteria were isolated from the consortia and of these 34 grew with the PAH mixture as a sole carbon source. Of these, isolates most closely related to Alterierythrobacter, Citricella, Erythrobacter, Idiomarina, Lutibacterium, Maricaulis, Marinobacter, Martelella, Pseudidiomarina, Rhodobacter, Roseovarius, Salipiger, Sphingopyxis and Stappia were found to

  20. Cell size dependence of additive versus synergetic effects of UV radiation and PAHs on oceanic phytoplankton

    International Nuclear Information System (INIS)

    Echeveste, Pedro; Agusti, Susana; Dachs, Jordi

    2011-01-01

    Polycyclic Aromatic Hydrocarbons' (PAHs) toxicity is enhanced by the presence of ultraviolet radiation (UVR), which levels have arisen due to the thinning of the ozone layer. In this study, PAHs' phototoxicity for natural marine phytoplankton was tested. Different concentrations of a mixture of 16 PAHs were added to natural phytoplankton communities from the Mediterranean Sea, Atlantic, Arctic and Southern Oceans and exposed to natural sunlight received in situ, including treatments where the UVR bands were removed. PAHs' toxicity was observed for all the phytoplankton groups studied in all the waters and treatments tested, but only for the pico-sized group a synergetic effect of the mixture and UVR was observed (p = 0.009). When comparing phototoxicity in phytoplankton from oligotrophic and eutrophic waters, synergy was only observed at the oligotrophic communities (p = 0.02) where pico-sized phytoplankton dominated. The degree of sensitivity was related to the trophic degree, decreasing as Chlorophyll a concentration increased. - Highlights: → The smallest picocyanobacteria were the most sensitive to PAHs and UVR. → PAHs-UVR synergism for the picophytoplankton and the oligotrophic communities. → PAHs-UVR additivity for the nanophytoplankton and the eutrophic communities. → An irradiance threshold is suggested to determine the joint action of UVR and PAHs. - Cell size and UVR levels determine additive/synergetic effects of PAHs and UVR to oceanic phytoplankton.

  1. Polycyclic aromatic hydrocarbon (PAH) contamination in the sediments of east coast peninsular Malaysia

    International Nuclear Information System (INIS)

    Mohd Suhaimi Elias; Abdul Khalik Wood; Zaleha Hashim; Wee Boon Siong; Mohd Suhaimi Hamzah; Shamsiah Abdul Rahman; Nazaratul Ashifa Abdullah Salim; Ariffin Talib

    2007-01-01

    The polycyclic hydrocarbons (PAHs) are pollutants of concern due to their persistent in the marine ecosystem, thus its can cause long-term adverse effect to the marine life. In this study the concentrations of PAHs in east coast Peninsular Malaysia sediments were determined. About ten stations along the east coast of the coastal area were selected to collect sediments sample using grab sampler. The PAHs from the sediment samples were soxhlet extracted using mixture of hexane and dichloromethane (DCM). Fractionation was done using the silica-alumina column. About 17 compounds of the PAHs were determined using the Gas Chromatography-Mass Spectrometer (GCMS model QP5050A). The Σ PAHs was found in the range between 0.26 μg/ g to 0.59 μg/ g dry weight. The data from the study signified that the main source of PAHs in the sediment of the east coast peninsular Malaysia is originated from the pyrolytic source. (author)

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

    Science.gov (United States)

    Hudgins, Douglas M.

    2005-01-01

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

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

    Science.gov (United States)

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

    2016-10-01

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

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

    Directory of Open Access Journals (Sweden)

    Edward .

    2014-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Xuezhu Zhu

    2016-08-01

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

  6. The Quantitative Resolution of a Mixture of Group II Metal Ions by Thermometric Titration with EDTA. An Analytical Chemistry Experiment.

    Science.gov (United States)

    Smith, Robert L.; Popham, Ronald E.

    1983-01-01

    Presents an experiment in thermometric titration used in an analytic chemistry-chemical instrumentation course, consisting of two titrations, one a mixture of calcium and magnesium, the other of calcium, magnesium, and barium ions. Provides equipment and solutions list/specifications, graphs, and discussion of results. (JM)

  7. Effect of single and mixed polycyclic aromatic hydrocarbon contamination on plant biomass yield and PAH dissipation during phytoremediation.

    Science.gov (United States)

    Afegbua, Seniyat Larai; Batty, Lesley Claire

    2018-04-27

    Polycyclic aromatic hydrocarbon (PAH)-contaminated sites have a mixture of PAH of varying concentration which may affect PAH dissipation differently to contamination with a single PAH. In this study, pot experiments investigated the impact of PAH contamination on Medicago sativa, Lolium perenne, and Festuca arundinacea biomass and PAH dissipation from soils spiked with phenanthrene (Phe), fluoranthene (Flu), and benzo[a]pyrene (B[a]P) in single and mixed treatments. Stimulatory or inhibitory effects of PAH contamination on plant biomass yields were not different for the single and mixed PAH treatments. Results showed significant effect of PAH treatments on plant growth with an increased root biomass yield for F. arundinacea in the Phe (175%) and Flu (86%) treatments and a root biomass decrease in the mixed treatment (4%). The mean residual PAHs in the planted treatments and unplanted control for the single treatments were not significantly different. B[a]P dissipation was enhanced for single and mixed treatments (71-72%) with F. arundinacea compared to the unplanted control (24-50%). On the other hand, B[a]P dissipation was inhibited with L. perenne (6%) in the single treatment and M. sativa (11%) and L. perenne (29%) in the mixed treatment. Abiotic processes had greater contribution to PAH dissipation compared to rhizodegradation in both treatments. In most cases, a stimulatory effect of PAH contamination on plant biomass yield without an enhancement of PAH dissipation was observed. Plant species among other factors affect the relative contribution of PAH dissipation mechanisms during phytoremediation. These factors determine the effectiveness and suitability of phytoremediation as a remedial strategy for PAH-contaminated sites. Further studies on impact of PAH contamination, plant selection, and rhizosphere activities on soil microbial community structure and remediation outcome are required.

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

    Science.gov (United States)

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

    2018-02-01

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

  9. Pollution by polycyclic aromatic hydrocarbons (PAH's) in sediments and organisms from Salina Cruz Port, Oaxaca, Mexico

    International Nuclear Information System (INIS)

    Botello, A.V.; Villanueva, S.; Diaz, G.; Pica, Y.

    1995-01-01

    The presence and levels of polycyclic aromatic hydrocarbons (PAH's) in [sediments and biota from the Port of Salina Cruz, Oaxaca; were evaluated by means of gas capillary chromatography using columns of high resolution. The results show a seasonal variability of the PAH's concentrations in sediments being higher in the port area and lower in oceanic sediments. The increase of the PAH's levels in Crassostrea iridiscens and Penaeus stylirostris is important and related to the bioaccumulation process. The presence of PAH's conformed by 4 y 5 benzene rings in these species must be noted specially because they have carcinogenic properties and their effects on the local fisheries should be considered. (Author)

  10. Investigation of the release of PAHs from artificially contaminated sediments using cyclolipopeptidic biosurfactants.

    Science.gov (United States)

    Portet-Koltalo, F; Ammami, M T; Benamar, A; Wang, H; Le Derf, F; Duclairoir-Poc, C

    2013-10-15

    Polycyclic aromatic hydrocarbons (PAHs) can be preponderant in contaminated sediments and understanding how they are sorbed in the different mineral and organic fractions of the sediment is critical for effective removal strategies. For this purpose, a mixture of seven PAHs was studied at the sediment/water interface and sorption isotherms were obtained. The influence of various factors on the sorption behavior of PAHs was evaluated, such as the nature of minerals, pH, ionic strength and amount of organic matter. Afterwards, the release of PAHs from the sediment by surfactants was investigated. The effectiveness of sodium dodecyl sulfate (SDS) was compared to natural biosurfactants, of cyclolipopeptidic type (amphisin and viscosin-like mixture), produced by two Pseudomonas fluorescens strains. The desorption of PAHs (from naphthalene to pyrene), from the highly retentive kaolinite fraction, could be favored by adding SDS or amphisin, but viscosin-like biosurfactants were only effective for 2-3 ring PAHs desorption (naphthalene to phenanthrene). Moreover, while SDS favors the release of all the target PAHs from a model sediment containing organic matter, the two biosurfactants tested were only effective to desorb the lowest molecular weight PAHs (naphthalene to fluorene). Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Polycyclic aromatic hydrocarbons (PAHs) biodegradation potential and diversity of microbial consortia enriched from tsunami sediments in Miyagi, Japan.

    Science.gov (United States)

    Bacosa, Hernando Pactao; Inoue, Chihiro

    2015-01-01

    The Great East Japan Earthquake caused tsunamis and resulted in widespread damage to human life and infrastructure. The disaster also resulted in contamination of the environment by chemicals such as polycyclic aromatic hydrocarbons (PAHs). This study was conducted to investigate the degradation potential and describe the PAH-degrading microbial communities from tsunami sediments in Miyagi, Japan. PAH-degrading bacteria were cultured by enrichment using PAH mixture or pyrene alone as carbon and energy sources. Among the ten consortia tested for PAH mixture, seven completely degraded fluorene and more than 95% of phenanthrene in 10 days, while only four consortia partially degraded pyrene. Six consortia partially degraded pyrene as a single substrate. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) revealed that each sample was dominated by unique microbial populations, regardless of sampling location. The consortia were dominated by known PAHs degraders including Sphingomonas, Pseudomonas, and Sphingobium; and previously unknown degraders such as Dokdonella and Luteimonas. A potentially novel and PAH-degrading Dokdonella was detected for the first time. PAH-ring hydroxylating dioxygenase (PAH-RHDα) gene was shown to be more effective than nidA in estimating pyrene-degrading bacteria in the enriched consortia. The consortia obtained in this study are potential candidates for remediation of PAHs contaminated soils. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. PAHs soil decontamination in two steps: desorption and electrochemical treatment.

    Science.gov (United States)

    Alcántara, M Teresa; Gómez, Jose; Pazos, Marta; Sanromán, M Angeles

    2009-07-15

    The presence of carcinogenic polycyclic aromatic hydrocarbons (PAHs) in soils poses a potential threat to human health if exposure levels are too high. Nevertheless, the removal of these contaminants presents a challenge to scientists and engineers. The high hydrophobic nature of PAHs enables their strong sorption onto soil or sediments. Thus, the use of surfactants could favour the release of sorbed hydrophobic organic compounds from contaminated soils. In this work, five surfactants, namely Brij 35, Tergitol NP10, Tween 20, Tween 80 and Tyloxapol, are evaluated on the desorption of PAHs [benzanthracene (BzA), fluoranthene (FLU), and pyrene (PYR), single and in mixture] from a model sample such as kaolin. In all cases, the best results were obtained when Tween 80 was employed. In order to obtain the global decontamination of PAHs, their electrochemical degradation is investigated. It is concluded that the order of increasing degradation for single compounds is BzA>FLU>PYR when they are subject to the same electrochemical treatment. In addition, there is a direct relationship between the ionization potential and the electrochemical degradation of PAH.

  13. Determination of mixture valence plutonium and multicomponent by computer resolution analysis of absorption spectrum (UV/VIS/NIR) (CRAAS)

    International Nuclear Information System (INIS)

    Zhuang Weixin; Ye Guoan; Huang Lifeng; Sun Hongfang; Zhao Yanju

    1996-09-01

    A spectrophotometry has been developed which can directly determine a multi-component sample by spectrophotometry without any chemical separation. CRAAS (Computer Resolution Analysis of Absorption Spectrum) has been reported. It is different from the previous spectrophotometry depending on only one or several special absorption peak. The CRAAS deals with the whole region of absorption spectrum by mathematical statistics. So CRAAS has higher accuracy, stronger power and very high resolution. The trouble comes from overlap of different spectrum in each other has been solved because CRAAS depends on the whole spectrum. As long as two spectra have different shape, their concentrations can be determined even their special absorption peaks are seriously overlapped. The accuracy is about +-5%. (2 refs., 7 figs., 8 tabs.)

  14. Complex mixtures biostudies

    International Nuclear Information System (INIS)

    Springer, D.L.

    1987-01-01

    The objective of the project is to identify potential adverse biological activities associated with human exposures to complex organic mixtures (COM) from energy-related industries. Studies to identify the influence of chemical class fractions from a COM on the initiating activity of a known carcinogen, benzo(a)pyrene (BaP), demonstrated that the polycyclic aromatic hydrocarbons (PAH) and nitrogen-containing polycyclic aromatic compound (NPAC) fractions were the most effective inhibitors of initiation. In an effort to determine the contribution of BaP to the initiating activity of the COM, binding of radiolabeled BaP to mouse skin DNA was measured. Results indicated that binding of BaP to DNA decreased in the presence of the COM so that at initiating COM doses, BaP binding was near the limit detection. Addition of unlabeled BaP to the COM at an amount similar to that originally present in the COM did not significantly increase the binding. Studies to determine the rates of disappearance of carcinogenic PAH from the site of application on the skin indicated that half-lives for PAH differed by a factor of about 2. Analytical methods developed to identify PAH from COM which covalently bind to DNA demonstrated that the lower level of detection is approximately 200 picograms. Developmental studies demonstrated that both pregnant rats and mice treated dermally with a high-boiling COM developed fetuses with major malformations including cleft palate, small lungs, edema, and sagittal suture hemorrhages. 3 figures, 5 tables

  15. Resolution of enantiopure (S)-1-(1-napthyl) ethanol from racemic mixture by a novel Bacillus cereus isolate.

    Science.gov (United States)

    Ranjan, Preeti; Pandey, Ashok; Binod, Parameswaran

    2017-09-01

    Chiral intermediates have wide application and high demand in pharmaceutical, agricultural, and other biotechnological industries for the preparation of bulk drug substances or fine chemicals. (S)-1-(1-napthyl) ethanol is an important synthetic intermediate of mevinic acid analog and a potential inhibitor of 3-hydroxy methyl glutaryl coenzyme A reductase enzymes which is rate limiting for cholesterol synthesis. The present study focuses on the resolution of (RS)-1-(1-napthyl) ethanol using whole cell biotransformation approach. The screening of microbial strains for the specific conversion were performed by the enrichment techniques using (RS)-1-(1-napthyl) ethanol. Evaluation of resolution, i.e., the enantioselective conversion of (R)-1-(1-napthyl) ethanol into 1-acetonapthone and production of (S)-1-(1-napthyl) ethanol with high purity were carried out. Among the isolates, a novel strain Bacillus cereus WG3 was found to be potent for the resolution and conversion of (S)-1-(1-napthyl) ethanol. This strain showed 86% conversion of (R)-1-(1-napthyl) ethanol and 95% yield of S-1-(1-napthyl) ethanol with 80% ee after 24 h. Further, the optimization of biotransformation reactions was carried out and the optimal parameters were found to be pH 7.0 and temperature 30 °C. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. A Decision Mixture Model-Based Method for Inshore Ship Detection Using High-Resolution Remote Sensing Images.

    Science.gov (United States)

    Bi, Fukun; Chen, Jing; Zhuang, Yin; Bian, Mingming; Zhang, Qingjun

    2017-06-22

    With the rapid development of optical remote sensing satellites, ship detection and identification based on large-scale remote sensing images has become a significant maritime research topic. Compared with traditional ocean-going vessel detection, inshore ship detection has received increasing attention in harbor dynamic surveillance and maritime management. However, because the harbor environment is complex, gray information and texture features between docked ships and their connected dock regions are indistinguishable, most of the popular detection methods are limited by their calculation efficiency and detection accuracy. In this paper, a novel hierarchical method that combines an efficient candidate scanning strategy and an accurate candidate identification mixture model is presented for inshore ship detection in complex harbor areas. First, in the candidate region extraction phase, an omnidirectional intersected two-dimension scanning (OITDS) strategy is designed to rapidly extract candidate regions from the land-water segmented images. In the candidate region identification phase, a decision mixture model (DMM) is proposed to identify real ships from candidate objects. Specifically, to improve the robustness regarding the diversity of ships, a deformable part model (DPM) was employed to train a key part sub-model and a whole ship sub-model. Furthermore, to improve the identification accuracy, a surrounding correlation context sub-model is built. Finally, to increase the accuracy of candidate region identification, these three sub-models are integrated into the proposed DMM. Experiments were performed on numerous large-scale harbor remote sensing images, and the results showed that the proposed method has high detection accuracy and rapid computational efficiency.

  17. The diversity of PAH-degrading bacteria in a deep-sea water column above the Southwest Indian Ridge

    Science.gov (United States)

    Yuan, Jun; Lai, Qiliang; Sun, Fengqin; Zheng, Tianling; Shao, Zongze

    2015-01-01

    The bacteria involved in organic pollutant degradation in pelagic deep-sea environments are largely unknown. In this report, the diversity of polycyclic aromatic hydrocarbon (PAH)-degrading bacteria was analyzed in deep-sea water on the Southwest Indian Ridge (SWIR). After enrichment with a PAH mixture (phenanthrene, anthracene, fluoranthene, and pyrene), nine bacterial consortia were obtained from depths of 3946–4746 m. While the consortia degraded all four PAHs when supplied in a mixture, when PAHs were tested individually, only phenanthrene supported growth. Thus, degradation of the PAH mixture reflected a cometabolism of anthracene, fluoranthene, and pyrene with phenanthrene. Further, both culture-dependent and independent methods revealed many new bacteria involved in PAH degradation. Specifically, the alpha and gamma subclasses of Proteobacteria were confirmed as the major groups within the communities. Additionally, Actinobacteria, the CFB group and Firmicutes were detected. Denaturing Gradient Gel Electrophoresis (DGGE) analysis showed that bacteria closely affiliated with Alcanivorax, Novosphingobium, and Rhodovulum occurred most frequently in different PAH-degrading consortia. By using general heterotrophic media, 51 bacteria were isolated from the consortia and of these 34 grew with the PAH mixture as a sole carbon source. Of these, isolates most closely related to Alterierythrobacter, Citricella, Erythrobacter, Idiomarina, Lutibacterium, Maricaulis, Marinobacter, Martelella, Pseudidiomarina, Rhodobacter, Roseovarius, Salipiger, Sphingopyxis, and Stappia were found to be PAH degraders. To the best of our knowledge, this is the first time these bacteria have been identified in this context. In summary, this report revealed significant diversity among the PAH-degrading bacteria in the deep-sea water column. These bacteria may play a role in PAH removal in deep-sea environments. PMID:26379634

  18. The diversity of PAH-degrading bacteria in a deep-sea water column above the Southwest Indian Ridge.

    Science.gov (United States)

    Yuan, Jun; Lai, Qiliang; Sun, Fengqin; Zheng, Tianling; Shao, Zongze

    2015-01-01

    The bacteria involved in organic pollutant degradation in pelagic deep-sea environments are largely unknown. In this report, the diversity of polycyclic aromatic hydrocarbon (PAH)-degrading bacteria was analyzed in deep-sea water on the Southwest Indian Ridge (SWIR). After enrichment with a PAH mixture (phenanthrene, anthracene, fluoranthene, and pyrene), nine bacterial consortia were obtained from depths of 3946-4746 m. While the consortia degraded all four PAHs when supplied in a mixture, when PAHs were tested individually, only phenanthrene supported growth. Thus, degradation of the PAH mixture reflected a cometabolism of anthracene, fluoranthene, and pyrene with phenanthrene. Further, both culture-dependent and independent methods revealed many new bacteria involved in PAH degradation. Specifically, the alpha and gamma subclasses of Proteobacteria were confirmed as the major groups within the communities. Additionally, Actinobacteria, the CFB group and Firmicutes were detected. Denaturing Gradient Gel Electrophoresis (DGGE) analysis showed that bacteria closely affiliated with Alcanivorax, Novosphingobium, and Rhodovulum occurred most frequently in different PAH-degrading consortia. By using general heterotrophic media, 51 bacteria were isolated from the consortia and of these 34 grew with the PAH mixture as a sole carbon source. Of these, isolates most closely related to Alterierythrobacter, Citricella, Erythrobacter, Idiomarina, Lutibacterium, Maricaulis, Marinobacter, Martelella, Pseudidiomarina, Rhodobacter, Roseovarius, Salipiger, Sphingopyxis, and Stappia were found to be PAH degraders. To the best of our knowledge, this is the first time these bacteria have been identified in this context. In summary, this report revealed significant diversity among the PAH-degrading bacteria in the deep-sea water column. These bacteria may play a role in PAH removal in deep-sea environments.

  19. Germination of Lepidium sativum as a method to evaluate polycyclic aromatic hydrocarbons (PAHs) removal from contaminated soil

    CSIR Research Space (South Africa)

    Maila, MP

    2002-01-01

    Full Text Available The sensitivity of Lepidium sativum germination to polycyclic aromatic hydrocarbons (PAHs) was investigated in soil(s) artificially and historically contaminated with mixtures of PAR The level of germination of L. sativum decreased with increasing...

  20. Determination of parent and hydroxy PAHs in personal PM{sub 2.5} and urine samples collected during Native American fish smoking activities

    Energy Technology Data Exchange (ETDEWEB)

    Motorykin, Oleksii [Department of Chemistry, Oregon State University, Corvallis, OR 97331 (United States); Schrlau, Jill; Jia, Yuling [Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, OR 97331 (United States); Harper, Barbara; Harris, Stuart [Department of Science and Engineering, Confederated Tribes of the Umatilla Indian Reservation, Pendleton, OR 97801 (United States); Harding, Anna [School of Biological and Population Health Sciences, Oregon State University, Corvallis, OR 97331 (United States); Stone, David [Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, OR 97331 (United States); Kile, Molly [School of Biological and Population Health Sciences, Oregon State University, Corvallis, OR 97331 (United States); Sudakin, Daniel [Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, OR 97331 (United States); Massey Simonich, Staci L., E-mail: staci.simonich@orst.edu [Department of Chemistry, Oregon State University, Corvallis, OR 97331 (United States); Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, OR 97331 (United States)

    2015-02-01

    A method was developed for the measurement of 19 parent PAHs (PAHs) and 34 hydroxylated PAHs (OH-PAHs) in urine and personal air samples of particulate matter less than 2.5 μm in diameter (PM{sub 2.5}) using GC–MS and validated using NIST SRM 3672 (Organic Contaminants in Smoker's Urine) and SRM 3673 (Organic Contaminants in Nonsmoker's Urine). The method was used to measure PAHs and OH-PAHs in urine and personal PM{sub 2.5} samples collected from the operators of two different fish smoking facilities (tipi and smoke shed) burning two different wood types (alder and apple) on the Confederated Tribes of Umatilla Indian Reservation (CTUIR) while they smoked salmon. Urine samples were spiked with β-glucuronidase/arylsulfatase to hydrolyze the conjugates of OH-PAHs and the PAHs and OH-PAHs were extracted using Plexa and C18 solid phases, in series. The 34 OH-PAHs were derivatized using MTBSTFA, and the mixture was measured by GC–MS. The personal PM{sub 2.5} samples were extracted using pressurized liquid extraction, derivatized with MTBSTFA and analyzed by GC–MS for PAHs and OH-PAHs. Fourteen isotopically labeled surrogates were added to accurately quantify PAHs and OH-PAHs in the urine and PM{sub 2.5} samples and three isotopically labeled internal standards were used to calculate the recovery of the surrogates. Estimated detection limits in urine ranged from 6.0 to 181 pg/ml for OH-PAHs and from 3.0 to 90 pg/ml for PAHs, and, in PM{sub 2.5}, they ranged from 5.2 to 155 pg/m{sup 3} for OH-PAHs and from 2.5 to 77 pg/m{sup 3} for PAHs. The results showed an increase in OH-PAH concentrations in urine after 6 h of fish smoking and an increase in PAH concentrations in air within each smoking facility. In general, the PAH exposure in the smoke shed was higher than in the tipi and the PAH exposure from burning apple wood was higher than burning alder. - Highlights: • An analytical method was developed for the measurement of 19 PAHs and 34 OH-PAHs.

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

    Science.gov (United States)

    Zhu, Li-Zhong; Wang, Jing

    2005-01-01

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

  2. Effect of isobaric breathing gas shifts from air to heliox mixtures on resolution of air bubbles in lipid and aqueous tissues of recompressed rats

    DEFF Research Database (Denmark)

    Hyldegaard, Ole; Kerem, Dikla; Melamed, Y

    2011-01-01

    Deep tissue isobaric counterdiffusion that may cause unwanted bubble formation or transient bubble growth has been referred to in theoretical models and demonstrated by intravascular gas formation in animals, when changing inert breathing gas from nitrogen to helium after hyperbaric air breathing....... We visually followed the in vivo resolution of extravascular air bubbles injected at 101 kPa into nitrogen supersaturated rat tissues: adipose, spinal white matter, skeletal muscle or tail tendon. Bubbles were observed during isobaric breathing-gas shifts from air to normoxic (80:20) heliox mixture...... breathing. No such bubble growth was observed in spinal white matter, skeletal muscle or tendon. In spinal white matter, an immediate breathing gas shift after the hyperbaric air exposure from air to both (80:20) and (50:50) heliox, coincident with recompression to either 285 or 405 kPa, caused consistent...

  3. Polycyclic aromatic hydrocarbons (PAHs) in a coal tar standard reference material - SRM 1597a updated

    Energy Technology Data Exchange (ETDEWEB)

    Wise, Stephen A.; Poster, Dianne L.; Rimmer, Catherine A.; Schubert, Patricia; Sander, Lane C.; Schantz, Michele M. [National Institute of Standards and Technology (NIST), Analytical Chemistry Division, Gaithersburg, MD (United States); Leigh, Stefan D. [National Institute of Standards and Technology (NIST), Statistical Engineering Division, Gaithersburg, MD (United States); Moessner, Stephanie [National Institute of Standards and Technology (NIST), Analytical Chemistry Division, Gaithersburg, MD (United States); GMP/Comparator Labs, Werthenstein Chemie AG, Industrie Nord, Schachen (Switzerland)

    2010-09-15

    SRM 1597 Complex Mixture of Polycyclic Aromatic Hydrocarbons from Coal Tar, originally issued in 1987, was recently reanalyzed and reissued as SRM 1597a with 34 certified, 46 reference, and 12 information concentrations (as mass fractions) for polycyclic aromatic hydrocarbons (PAHs) and polycyclic aromatic sulfur heterocycles (PASHs) including methyl-substituted PAHs and PASHs. The certified and reference concentrations (as mass fractions) were based on results of analyses of the coal tar material using multiple analytical techniques including gas chromatography/mass spectrometry on four different stationary phases and reversed-phase liquid chromatography. SRM 1597a is currently the most extensively characterized SRM for PAHs and PASHs. (orig.)

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

    Science.gov (United States)

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

    2018-03-01

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

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

    Science.gov (United States)

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

    2014-08-30

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

  6. Polycyclic aromatic hydrocarbons and PAH-related DNA adducts.

    Science.gov (United States)

    Ewa, Błaszczyk; Danuta, Mielżyńska-Švach

    2017-08-01

    Investigations on the impact of chemicals on the environment and human health have led to the development of an exposome concept. The exposome refers to the totality of exposures received by a person during life, including exposures to life-style factors, from the prenatal period to death. The exposure to genotoxic chemicals and their reactive metabolites can induce chemical modifications of DNA, such as, for example, DNA adducts, which have been extensively studied and which play a key role in chemically induced carcinogenesis. Development of different methods for the identification of DNA adducts has led to adopting DNA adductomic approaches. The ability to simultaneously detect multiple PAH-derived DNA adducts may allow for the improved assessment of exposure, and offer a mechanistic insight into the carcinogenic process following exposure to PAH mixtures. The major advantage of measuring chemical-specific DNA adducts is the assessment of a biologically effective dose. This review provides information about the occurrence of the polycyclic aromatic hydrocarbons (PAHs) and their influence on human exposure and biological effects, including PAH-derived DNA adduct formation and repair processes. Selected methods used for determination of DNA adducts have been presented.

  7. Rapid collection, detection, and assessment of environmental polycyclic aromatic hydrocarbons (PAHs)

    International Nuclear Information System (INIS)

    Johnson, T.; Huckins, J.; Petty, J.; Butorin, A.

    1995-01-01

    PAHs, an important class of environmental chemical contaminants found primarily in petroleum and coal products, frequently are the most numerous and ubiquitous organic pollutants recovered in sediment residues. PAHs are considered hazardous in water and soil because many are acutely toxic and have the potential for genotoxic activity. Selected EPA priority pollutants (2, 3, 4, and 5-ring PAHs) and complex PAH mixtures (crude oil, gasoline, and recycled motor oil) were collected and concentrated from water and sediment with semipermeable polymeric membrane devices (SPMDs) that contain a thin film of triolein. Analytes were extracted from the SPMDs by dialysis in hexane or directly by rinsing with acetone DMSO, concentrated in the carrier solvent DMSO, and detected with the luminescent bacterial assays Microtox reg-sign and Mutatox reg-sign. High SPMD-water concentration factors of PAHs appeared to correspond closely to the occurrence of PAHs in sediments previously reported in the literature; for example, pyrene had the highest SPMD concentration factor and was the most commonly found PAH in sediment residues. Mutatox reg-sign with rat hepatic S9 activation detected all PAHs tested. The PAH's molecular weight and number of rings appeared to directly influence acute toxicity (EC50, microg/mL); for example, two-ring naphthalene had an EC50 value of 0.78 whereas five-ring benzo(a)pyrene had an EC50 value of 15.0, about a twenty-fold difference, Microtox reg-sign and Mutatox reg-sign, in combination with SPMDs were able to rapidly (< 24h) assess the bioavailability, toxicity, and genotoxicity of these environmental PAHs

  8. PAH in tea and coffee

    DEFF Research Database (Denmark)

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

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

  9. The role of chemometrics in single and sequential extraction assays: a review. Part II. Cluster analysis, multiple linear regression, mixture resolution, experimental design and other techniques.

    Science.gov (United States)

    Giacomino, Agnese; Abollino, Ornella; Malandrino, Mery; Mentasti, Edoardo

    2011-03-04

    Single and sequential extraction procedures are used for studying element mobility and availability in solid matrices, like soils, sediments, sludge, and airborne particulate matter. In the first part of this review we reported an overview on these procedures and described the applications of chemometric uni- and bivariate techniques and of multivariate pattern recognition techniques based on variable reduction to the experimental results obtained. The second part of the review deals with the use of chemometrics not only for the visualization and interpretation of data, but also for the investigation of the effects of experimental conditions on the response, the optimization of their values and the calculation of element fractionation. We will describe the principles of the multivariate chemometric techniques considered, the aims for which they were applied and the key findings obtained. The following topics will be critically addressed: pattern recognition by cluster analysis (CA), linear discriminant analysis (LDA) and other less common techniques; modelling by multiple linear regression (MLR); investigation of spatial distribution of variables by geostatistics; calculation of fractionation patterns by a mixture resolution method (Chemometric Identification of Substrates and Element Distributions, CISED); optimization and characterization of extraction procedures by experimental design; other multivariate techniques less commonly applied. Copyright © 2010 Elsevier B.V. All rights reserved.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2000-03-01

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

  11. The use of lightweight expanded clay aggregate (LECA) as sorbent for PAHs removal from water

    International Nuclear Information System (INIS)

    Nkansah, Marian Asantewah; Christy, Alfred A.; Barth, Tanja; Francis, George William

    2012-01-01

    Highlights: ► Effect of contact time on sorption PAH by LECA. ► Effect of mass of sorbent (LECA) on sorption of PAH. ► Sorption Isotherms for PAH-LECA interaction. - Abstract: Lightweight expanded clay aggregate (LECA) has been explored as a sorbent for the removal of PAHs (phenanthrene, fluoranthene and pyrene) from water. The efficacy of LECA as a sorbent for PAHs was assessed using contact time, mass of sorbent and sorption isotherms in a series of batch experiments. Maximum (optimum) sorption was reached at 21 h after which the amount of PAHs sorbed remained almost constant. Batch experiments were conducted by shaking a 100 ml solution mixture of individual PAHs (containing 0.02 mg/L) with LECA. The maximum sorption was 70.70, 70.82 and 72.12%, respectively for phenanthrene, fluoranthene and pyrene when a mass of 0.2 g of sorbent was used. There was an increase in sorption as a result of an increase in mass of sorbent until a maximum was reached at a mass of 4.0 g LECA with 92.61, 93.91 and 94.15% sorption of phenanthrene, fluoranthene and pyrene respectively. Sorption data were fitted to the linearised forms of the Freundlich and Langmuir isotherm models to determine the water-LECA partitioning coefficient. Physical sorption caused by the aromatic nature of the compounds was the main mechanism that governed the removal process while the hydrophobicity of the PAHs also influenced the sorption capacity. LECA can be used as an alternative method for aqueous PAHs removal.

  12. Source characterisation and distribution of selected PCBs, PAHs and alkyl PAHs in sediments from the Klip and Jukskei Rivers, South Africa.

    Science.gov (United States)

    Rimayi, Cornelius; Chimuka, Luke; Odusanya, David; de Boer, Jacob; Weiss, Jana M

    2017-07-01

    A study of the distribution of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) utilising 16 priority PAHs, benzo(e)pyrene, perylene, 19 alkylated PAHs and 31 ortho substituted PCBs in South Africa is presented. It was aimed to (a) deduce characteristic contamination patterns for both PCBs and PAHs and (b) provide the first comprehensive dataset for establishment of source characterisation of PCBs and PAHs. This is in line with new South African legislation on mandatory monitoring of PCB and PAH emissions. Bar charts, principal component analysis (PCA) and biplots were utilised to identify signature contamination patterns and distribution of PCBs and PAHs within the Jukskei and Klip Rivers. Sediments from the Jukskei and Klip River catchments both showed distinct contamination signatures for hexa to nonachlorinated PCBs, characteristic of contamination by Aroclor 1254 and 1260 technical mixtures. PCB signature patterns in order of abundance were 138 > 180 > 206 > 153 > 187 > 149 and 138 > 153 > 180 > 149 > 187 > 110 > 170 for the Jukskei and Klip River sediments, respectively. The upstream Alberton point had the highest Σ31 PCB and Σ (parent+alkyl) PAH concentrations in the Klip River of 61 and 6000 μg kg -1 dry weight (dw), respectively. In the Jukskei River, the upstream Marlboro point had the highest Σ31 PCB concentration of 19 μg kg -1 dw and the N14 site recorded the highest Σ (parent+alkyl) PAH concentration of 2750 μg kg -1 dw. PAH concentrations in both the Jukskei and Klip Rivers were significantly higher than the PCB concentrations. Fluoranthene, phenanthrene and pyrene were found in the highest concentrations in both the Jukskei and Klip River sediments. Both the Jukskei and Klip River sediments showed trends of a mixed pyrogenic-petrogenic PAH source contamination.

  13. Interstellar dehydrogenated PAH anions: vibrational spectra

    Science.gov (United States)

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

    2018-03-01

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

  14. Temperature optimization for the separation of PAHs on micropacked LC ODS columns

    NARCIS (Netherlands)

    Chen, J.; Steenackers, D.; Sandra, P.J.F.; Sandra, P.J.F.; Devos, G.

    1993-01-01

    The effect of column temperature on the separation of the sixteen polycyclic aromatic hydrocarbons (PAHs) of mixture SRM 1647a of the US Environmental Protection Agency has been studied on different micropacked ODS columns. lsothermal temperature optimization was successfully applied for complete

  15. Temperature optimization for the separation of PAHs on micropacked LC ODS columns

    NARCIS (Netherlands)

    Chen, J.; Steenackers, D.; Medvedovici, A.; Sandra, P.J.F.

    1993-01-01

    The effect of column temperature on the separation of the sixteen polycyclic aromatic hydrocarbons (PAHs) of mixture SRM 1647a of the US Environmental Protection Agency has been studied on different micropacked ODS columns. Isothermal temperature optimization was successfully used for complete

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

    Science.gov (United States)

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

    2017-09-01

    Spectral features from polycyclic aromatic hydrocarbon (PAH) molecules observed in the mid-infrared (mid-IR) range are typically used to infer the amount of recent and ongoing star formation on kiloparsec scales around active galactic nuclei (AGN) where more traditional methods fail. This method assumes that the observed PAH features are excited predominantly by star formation. With current ground-based telescopes and the upcoming James Webb Space Telescope, much smaller spatial scales can be probed and we aim at testing if this assumption still holds in the range of few tens to few hundreds of parsecs. For that, we spatially map the emitted 11.3 μm PAH surface flux as a function of distance from 0.4-4 arcsec from the centre in 28 nearby AGN using ground-based high-angular-resolution mid-IR spectroscopy. We detect and extract the 11.3 μm PAH feature in 13 AGN. The fluxes within each aperture are scaled to a luminosity-normalized distance from the nucleus to be able to compare intrinsic spatial scales of AGN radiation spanning about two orders of magnitude in luminosity. For this, we establish an empirical relation between the absorption-corrected X-ray luminosity and the sublimation radius in these sources. Once normalized, the radial profiles of the emitted PAH surface flux show similar radial slopes, with a power-law index of approximately -1.1, and similar absolute values, consistent within a factor of a few of each other as expected from the uncertainty in the intrinsic scale estimate. We interpret this as evidence that the profiles are caused by a common compact central physical process, either the AGN itself or circumnuclear star formation linked in strength to the AGN power. A photoionization-based model of an AGN exciting dense clouds in its environment can reproduce the observed radial slope and confirms that the AGN radiation field is strong enough to explain the observed PAH surface fluxes within ∼10-500 pc of the nucleus. Our results advice caution

  17. Processes controlling PAH leaching from two industrial sites

    Energy Technology Data Exchange (ETDEWEB)

    Jouannin, F. [Lab. d' Analyse Environmental des Procedes et des Systemes Industrielles, INSA de Lyon, Villeurbanne (France); Barna, R. [Lab. d' Analyse Environmental des Procedes et des Systemes Industrielles, INSA de Lyon, Villeurbanne (France)]|[Centre Energetique Environnement, Ecole des Mines d' Albi, Albi (France); Vernus, E. [POLDEN, INSA de Lyon, Villeurbanne (France)

    2002-07-01

    The persistence of hydrophobic organic pollutants like PAHs in weathered contaminated soils is a major impediment to their successful remediation. This persistence is caused by slow desorption and/or dissolution processes, resulting in small release rates of contaminants and therefore low concentrations in groundwater (Grathwohl, 1998). Laboratory experiments to assess the PAHs release are realised in stirred batch or with traditional percolation column. These two kind of tests show their limits in different cases like particulate disagregation by stirring or in the difficulty to control the soil/solution contact time in column experiments. Consequently a new experimental procedure is proposed, in which the compacted immobile soil is in contact with the eluate recycled in an inner loop. Two different soils containing HAPs (high and low polluted) were tested according to the new procedure. Different extracting solutions have been used: demineralised water, NaN{sub 3} and CaCl{sub 2} solutions. A water/methanol mixture has also been used to increase pollutants release by increasing their solubility. This is a first step in the elaboration of an assessment methodology of the PAHs mobility in soils. (orig.)

  18. PAHs and the Diffuse Interstellar Bands. What have we Learned from the New Generation of Laboratory and Observational Studies?

    Science.gov (United States)

    Salama, Farid

    2005-01-01

    Polycyclic Aromatic Hydrocarbons (PAHs) are an important and ubiquitous component of carbon-bearing materials in space. PAHs are the best-known candidates to account for the IR emission bands (UIR bands) and PAH spectral features are now being used as new probes of the ISM. PAHs are also thought to be among the carriers of the diffuse interstellar absorption bands (DIBs). In the model dealing with the interstellar spectral features, PAHs are present as a mixture of radicals, ions and neutral species. PAH ionization states reflect the ionization balance of the medium while PAH size, composition, and structure reflect the energetic and chemical history of the medium. A major challenge for laboratory astrophysics is to reproduce (in a realistic way) the physical conditions that exist in the emission and/or absorption interstellar zones, An extensive laboratory program has been developed at NASA Ames to characterize the physical and chemical properties of PAHs in astrophysical environments and to describe how they influence the radiation and energy balance in space and the interstellar chemistry. In particular, laboratory experiments provide measurements of the spectral characteristics of interstellar PAH analogs from the ultraviolet and visible range to the infrared range for comparison with astronomical data. This paper will focus on the recent progress made in the laboratory to measure the direct absorption spectra of neutral and ionized PAHs in the gas phase in the near-W and visible range in astrophysically relevant environments. These measurements provide data on PAHs and nanometer-sized particles that can now be directly compared to astronomical observations. The harsh physical conditions of the IS medium - characterized by a low temperature, an absence of collisions and strong V W radiation fields - are simulated in the laboratory by associating a molecular beam with an ionizing discharge to generate a cold plasma expansion. PAH ions are formed from the neutral

  19. Occupational PAH Exposures during Prescribed Pile Burns

    Science.gov (United States)

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

    2008-01-01

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

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

    Science.gov (United States)

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

    2013-05-01

    PAHs in the morning, when there is more vehicular traffic. The time series of PAHs also exhibit synchronized peaks of PAHs and DC that correspond to hours of traffic which shows the relationship of PAHs with DC. However, correlations of PAHs with DC show a relatively strong scattering suggesting that aerosols are a mixture of particles of different sources and different ages. Throughout the day is observed the aging of primary combustion particles due to the secondary aerosols coating. This coating may prolong the life time of the PAHs in the atmosphere. Also occurs a decrease in the ratio PAHs / DC during the day. Low ratios indicate the abundance of large particles, whereas high ratios indicate abundance dominated by small particle emissions from diesel engines. The resulting correlations show a significant linear trend evolution of PAHs with NOx, indicating that the PAHs are associated with the combustion of diesel, and a linear trend of PAHs with DC for each type of aerosol combustion, while the correlation of PAHs with CO results in an exponential trend which implies that PAHs are related to the combustion of diesel.

  1. PAHS

    African Journals Online (AJOL)

    user

    2011-03-02

    Mar 2, 2011 ... spillage's and/or heavy ship traffic. However, the ... various aspects such as industrial effluents, air, highway vehicle exhaust and highway .... detection (LOD) of the GC-MS method, established at signals three times that of the.

  2. Soot modeling of counterflow diffusion flames of ethylene-based binary mixture fuels

    KAUST Repository

    Wang, Yu; Raj, Abhijeet Dhayal; Chung, Suk-Ho

    2015-01-01

    of ethylene and its binary mixtures with methane, ethane and propane based on the method of moments. The soot model has 36 soot nucleation reactions from 8 PAH molecules including pyrene and larger PAHs. Soot surface growth reactions were based on a modified

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

    Science.gov (United States)

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

    2016-03-01

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

  4. Regional modelling of polycyclic aromatic hydrocarbons: WRF-Chem-PAH model development and East Asia case studies

    Science.gov (United States)

    Mu, Qing; Lammel, Gerhard; Gencarelli, Christian N.; Hedgecock, Ian M.; Chen, Ying; Přibylová, Petra; Teich, Monique; Zhang, Yuxuan; Zheng, Guangjie; van Pinxteren, Dominik; Zhang, Qiang; Herrmann, Hartmut; Shiraiwa, Manabu; Spichtinger, Peter; Su, Hang; Pöschl, Ulrich; Cheng, Yafang

    2017-10-01

    Polycyclic aromatic hydrocarbons (PAHs) are hazardous pollutants, with increasing emissions in pace with economic development in East Asia, but their distribution and fate in the atmosphere are not yet well understood. We extended the regional atmospheric chemistry model WRF-Chem (Weather Research Forecast model with Chemistry module) to comprehensively study the atmospheric distribution and the fate of low-concentration, slowly degrading semivolatile compounds. The WRF-Chem-PAH model reflects the state-of-the-art understanding of current PAHs studies with several new or updated features. It was applied for PAHs covering a wide range of volatility and hydrophobicity, i.e. phenanthrene, chrysene and benzo[a]pyrene, in East Asia. Temporally highly resolved PAH concentrations and particulate mass fractions were evaluated against observations. The WRF-Chem-PAH model is able to reasonably well simulate the concentration levels and particulate mass fractions of PAHs near the sources and at a remote outflow region of East Asia, in high spatial and temporal resolutions. Sensitivity study shows that the heterogeneous reaction with ozone and the homogeneous reaction with the nitrate radical significantly influence the fate and distributions of PAHs. The methods to implement new species and to correct the transport problems can be applied to other newly implemented species in WRF-Chem.

  5. Multicomponent mixed dopant optimization for rapid screening of polycyclic aromatic hydrocarbons using ultra high performance liquid chromatography coupled to atmospheric pressure photoionization high-resolution mass spectrometry

    KAUST Repository

    Sioud, Salim

    2012-05-04

    RATIONALE To enhance the ionization efficiencies in atmospheric pressure photoionization mass spectrometry a dopant with favorable ionization energy such as chlorobenzene is typically used. These dopants are typically toxic and difficult to mix with water-soluble organic solvents. In order to achieve a more efficient and less toxic dopant, a multicomponent mixed dopant was explored. METHODS A multicomponent mixed dopant for non-targeted rapid screening of polycyclic aromatic hydrocarbons (PAHs) was developed and optimized using ultra high performance liquid chromatography (UPLC) coupled to atmospheric pressure photoionization high-resolution mass spectrometry. Various single and multicomponent mixed dopants consisting of ethanol, chlorobenzene, bromobenzene, anisole and toluene were evaluated. RESULTS Fourteen out of eighteen PAHs were successfully separated and detected at low pg/μL levels within 5 min with high mass accuracy ≤4 ppm. The optimal mixed multicomponent dopant consisted of ethanol/chlorobenzene/bromobenzene/anisole (98.975:0.1:0.9:0.025, v/v %) and it improved the limit of detection (LOD) by 2- to 10-fold for the tested PAHs compared to those obtained with pure chlorobenzene. CONCLUSIONS A novel multicomponent dopant that contains 99% ethanol and 1% mixture of chlorobenzene, bromobenzene and anisole was found to be an effective dopant mixture to ionize PAHs. The developed UPLC multicomponent dopant assisted atmospheric pressure photoionization high-resolution mass spectrometry offered a rapid non targeted screening method for detecting the PAHs at low pg/;μL levels within a 5 min run time with high mass accuracy a;circ4 ppm. Copyright © 2012 John Wiley & Sons, Ltd.

  6. Mobility and availability of PAH in soil-sewage sludges systems; Mobilite et disponibilite des HAP dans des systemes terre-boue de station d'epuration

    Energy Technology Data Exchange (ETDEWEB)

    Bryselbout, C

    2002-07-15

    This work deals with the increase of the availability of polycyclic aromatic hydrocarbons (PAH) induced by the supply of organic matter to a soil in the framework of the agricultural valorization of organic wastes. The sharing of PAH with the organic matter of a model of soil and sewage sludge mixture has been studied first, using extractions and adsorption kinetics (Kd methanol). Then, the evolution of the PAH availability in a sludge-earth mixture has ben studied over a period of 185 days. Finally, the plants PAH availability in the presence of residual sludge has been studied at the laboratory and in-situ. Results show that Kd methanol and PAH extractability in a earth-sludge mixture are proportional to the total organic carbon ratio and to the incubation time. The presence of sludges leads to the immobilization of a smaller amount of PAH. The PAH availability from a sludge-earth mixture is limited by the presence of sludge and cations, such as mercuric mercury. It seems that the organic matter of sludges is more washable than the one of the soil leading to an increased risk of migration of micro-pollutants in the environment. The agricultural valorization of organic wastes, as it is already implemented in France, does not indicate any direct effect on the mobility and availability of PAH in soils. However, a long-term effect on water and soil quality is to be feared. The limitation of PAH fluxes towards agricultural areas would be a societal answer. (J.S.)

  7. Mobility and availability of PAH in soil-sewage sludges systems; Mobilite et disponibilite des HAP dans des systemes terre-boue de station d'epuration

    Energy Technology Data Exchange (ETDEWEB)

    Bryselbout, C.

    2002-07-15

    This work deals with the increase of the availability of polycyclic aromatic hydrocarbons (PAH) induced by the supply of organic matter to a soil in the framework of the agricultural valorization of organic wastes. The sharing of PAH with the organic matter of a model of soil and sewage sludge mixture has been studied first, using extractions and adsorption kinetics (Kd methanol). Then, the evolution of the PAH availability in a sludge-earth mixture has ben studied over a period of 185 days. Finally, the plants PAH availability in the presence of residual sludge has been studied at the laboratory and in-situ. Results show that Kd methanol and PAH extractability in a earth-sludge mixture are proportional to the total organic carbon ratio and to the incubation time. The presence of sludges leads to the immobilization of a smaller amount of PAH. The PAH availability from a sludge-earth mixture is limited by the presence of sludge and cations, such as mercuric mercury. It seems that the organic matter of sludges is more washable than the one of the soil leading to an increased risk of migration of micro-pollutants in the environment. The agricultural valorization of organic wastes, as it is already implemented in France, does not indicate any direct effect on the mobility and availability of PAH in soils. However, a long-term effect on water and soil quality is to be feared. The limitation of PAH fluxes towards agricultural areas would be a societal answer. (J.S.)

  8. Comparison of techniques for estimating PAH bioavailability: Uptake in Eisenia fetida, passive samplers and leaching using various solvents and additives

    Energy Technology Data Exchange (ETDEWEB)

    Bergknut, Magnus [Department of Chemistry, Environmental Chemistry, Umeaa University, SE-90187 Umeaa (Sweden)]. E-mail: magnus.bergknut@chem.umu.se; Sehlin, Emma [Department of Chemistry, Environmental Chemistry, Umeaa University, SE-90187 Umeaa (Sweden); Lundstedt, Staffan [Department of Chemistry, Environmental Chemistry, Umeaa University, SE-90187 Umeaa (Sweden); Andersson, Patrik L. [Department of Chemistry, Environmental Chemistry, Umeaa University, SE-90187 Umeaa (Sweden); Haglund, Peter [Department of Chemistry, Environmental Chemistry, Umeaa University, SE-90187 Umeaa (Sweden); Tysklind, Mats [Department of Chemistry, Environmental Chemistry, Umeaa University, SE-90187 Umeaa (Sweden)

    2007-01-15

    The aim of this study was to evaluate different techniques for assessing the availability of polycyclic aromatic hydrocarbons (PAHs) in soil. This was done by comparing the amounts (total and relative) taken up by the earthworm Eisenia fetida with the amounts extracted by solid-phase microextraction (SPME), semi-permeable membrane devices (SPMDs), leaching with various solvent mixtures, leaching using additives, and sequential leaching. Bioconcentration factors of PAHs in the earthworms based on equilibrium partitioning theory resulted in poor correlations to observed values. This was most notable for PAHs with high concentrations in the studied soil. Evaluation by principal component analysis (PCA) showed distinct differences between the evaluated techniques and, generally, there were larger proportions of carcinogenic PAHs (4-6 fused rings) in the earthworms. These results suggest that it may be difficult to develop a chemical method that is capable of mimicking biological uptake, and thus estimating the bioavailability of PAHs. - The total and relative amounts of PAHs extracted by abiotic techniques for assessing the bioavailability of PAHs was found to differ from the amounts taken up by Eisenia fetida.

  9. Comparison of techniques for estimating PAH bioavailability: Uptake in Eisenia fetida, passive samplers and leaching using various solvents and additives

    International Nuclear Information System (INIS)

    Bergknut, Magnus; Sehlin, Emma; Lundstedt, Staffan; Andersson, Patrik L.; Haglund, Peter; Tysklind, Mats

    2007-01-01

    The aim of this study was to evaluate different techniques for assessing the availability of polycyclic aromatic hydrocarbons (PAHs) in soil. This was done by comparing the amounts (total and relative) taken up by the earthworm Eisenia fetida with the amounts extracted by solid-phase microextraction (SPME), semi-permeable membrane devices (SPMDs), leaching with various solvent mixtures, leaching using additives, and sequential leaching. Bioconcentration factors of PAHs in the earthworms based on equilibrium partitioning theory resulted in poor correlations to observed values. This was most notable for PAHs with high concentrations in the studied soil. Evaluation by principal component analysis (PCA) showed distinct differences between the evaluated techniques and, generally, there were larger proportions of carcinogenic PAHs (4-6 fused rings) in the earthworms. These results suggest that it may be difficult to develop a chemical method that is capable of mimicking biological uptake, and thus estimating the bioavailability of PAHs. - The total and relative amounts of PAHs extracted by abiotic techniques for assessing the bioavailability of PAHs was found to differ from the amounts taken up by Eisenia fetida

  10. Using deuterated PAH amendments to validate chemical extraction methods to predict PAH bioavailability in soils

    International Nuclear Information System (INIS)

    Gomez-Eyles, Jose L.; Collins, Chris D.; Hodson, Mark E.

    2011-01-01

    Validating chemical methods to predict bioavailable fractions of polycyclic aromatic hydrocarbons (PAHs) by comparison with accumulation bioassays is problematic. Concentrations accumulated in soil organisms not only depend on the bioavailable fraction but also on contaminant properties. A historically contaminated soil was freshly spiked with deuterated PAHs (dPAHs). dPAHs have a similar fate to their respective undeuterated analogues, so chemical methods that give good indications of bioavailability should extract the fresh more readily available dPAHs and historic more recalcitrant PAHs in similar proportions to those in which they are accumulated in the tissues of test organisms. Cyclodextrin and butanol extractions predicted the bioavailable fraction for earthworms (Eisenia fetida) and plants (Lolium multiflorum) better than the exhaustive extraction. The PAHs accumulated by earthworms had a larger dPAH:PAH ratio than that predicted by chemical methods. The isotope ratio method described here provides an effective way of evaluating other chemical methods to predict bioavailability. - Research highlights: → Isotope ratios can be used to evaluate chemical methods to predict bioavailability. → Chemical methods predicted bioavailability better than exhaustive extractions. → Bioavailability to earthworms was still far from that predicted by chemical methods. - A novel method using isotope ratios to assess the ability of chemical methods to predict PAH bioavailability to soil biota.

  11. Using deuterated PAH amendments to validate chemical extraction methods to predict PAH bioavailability in soils

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Eyles, Jose L., E-mail: j.l.gomezeyles@reading.ac.uk [University of Reading, School of Human and Environmental Sciences, Soil Research Centre, Reading, RG6 6DW Berkshire (United Kingdom); Collins, Chris D.; Hodson, Mark E. [University of Reading, School of Human and Environmental Sciences, Soil Research Centre, Reading, RG6 6DW Berkshire (United Kingdom)

    2011-04-15

    Validating chemical methods to predict bioavailable fractions of polycyclic aromatic hydrocarbons (PAHs) by comparison with accumulation bioassays is problematic. Concentrations accumulated in soil organisms not only depend on the bioavailable fraction but also on contaminant properties. A historically contaminated soil was freshly spiked with deuterated PAHs (dPAHs). dPAHs have a similar fate to their respective undeuterated analogues, so chemical methods that give good indications of bioavailability should extract the fresh more readily available dPAHs and historic more recalcitrant PAHs in similar proportions to those in which they are accumulated in the tissues of test organisms. Cyclodextrin and butanol extractions predicted the bioavailable fraction for earthworms (Eisenia fetida) and plants (Lolium multiflorum) better than the exhaustive extraction. The PAHs accumulated by earthworms had a larger dPAH:PAH ratio than that predicted by chemical methods. The isotope ratio method described here provides an effective way of evaluating other chemical methods to predict bioavailability. - Research highlights: > Isotope ratios can be used to evaluate chemical methods to predict bioavailability. > Chemical methods predicted bioavailability better than exhaustive extractions. > Bioavailability to earthworms was still far from that predicted by chemical methods. - A novel method using isotope ratios to assess the ability of chemical methods to predict PAH bioavailability to soil biota.

  12. Chemical and bioanalytical characterisation of PAHs in risk assessment of remediated PAH-contaminated soils.

    Science.gov (United States)

    Larsson, Maria; Hagberg, Jessika; Rotander, Anna; van Bavel, Bert; Engwall, Magnus

    2013-12-01

    Polycyclic aromatic hydrocarbons (PAHs) are common contaminants in soil at former industrial areas; and in Sweden, some of the most contaminated sites are being remediated. Generic guideline values for soil use after so-called successful remediation actions of PAH-contaminated soil are based on the 16 EPA priority pollutants, which only constitute a small part of the complex cocktail of toxicants in many contaminated soils. The aim of the study was to elucidate if the actual toxicological risks of soil samples from successful remediation projects could be reflected by chemical determination of these PAHs. We compared chemical analysis (GC-MS) and bioassay analysis (H4IIE-luc) of a number of remediated PAH-contaminated soils. The H4IIE-luc bioassay is an aryl hydrocarbon (Ah) receptor-based assay that detects compounds that activate the Ah receptor, one important mechanism for PAH toxicity. Comparison of the results showed that the bioassay-determined toxicity in the remediated soil samples could only be explained to a minor extent by the concentrations of the 16 priority PAHs. The current risk assessment method for PAH-contaminated soil in use in Sweden along with other countries, based on chemical analysis of selected PAHs, is missing toxicologically relevant PAHs and other similar substances. It is therefore reasonable to include bioassays in risk assessment and in the classification of remediated PAH-contaminated soils. This could minimise environmental and human health risks and enable greater safety in subsequent reuse of remediated soils.

  13. Detection and Resolution of Cryptosporidium Species and Species Mixtures by Genus-Specific Nested PCR-Restriction Fragment Length Polymorphism Analysis, Direct Sequencing, and Cloning ▿

    Science.gov (United States)

    Ruecker, Norma J.; Hoffman, Rebecca M.; Chalmers, Rachel M.; Neumann, Norman F.

    2011-01-01

    Molecular methods incorporating nested PCR-restriction fragment length polymorphism (RFLP) analysis of the 18S rRNA gene of Cryptosporidium species were validated to assess performance based on limit of detection (LoD) and for detecting and resolving mixtures of species and genotypes within a single sample. The 95% LoD was determined for seven species (Cryptosporidium hominis, C. parvum, C. felis, C. meleagridis, C. ubiquitum, C. muris, and C. andersoni) and ranged from 7 to 11 plasmid template copies with overlapping 95% confidence limits. The LoD values for genomic DNA from oocysts on microscope slides were 7 and 10 template copies for C. andersoni and C. parvum, respectively. The repetitive nested PCR-RFLP slide protocol had an LoD of 4 oocysts per slide. When templates of two species were mixed in equal ratios in the nested PCR-RFLP reaction mixture, there was no amplification bias toward one species over another. At high ratios of template mixtures (>1:10), there was a reduction or loss of detection of the less abundant species by RFLP analysis, most likely due to heteroduplex formation in the later cycles of the PCR. Replicate nested PCR was successful at resolving many mixtures of Cryptosporidium at template concentrations near or below the LoD. The cloning of nested PCR products resulted in 17% of the cloned sequences being recombinants of the two original templates. Limiting-dilution nested PCR followed by the sequencing of PCR products resulted in no sequence anomalies, suggesting that this method is an effective and accurate way to study the species diversity of Cryptosporidium, particularly for environmental water samples, in which mixtures of parasites are common. PMID:21498746

  14. The effects of LMWOAs on biodegradation of multi-component PAHs in aqueous solution using dual-wavelength fluorimetry

    International Nuclear Information System (INIS)

    Wei Xingyuan; Sang Lingzi; Chen Jianing; Zhu Yaxian; Zhang Yong

    2009-01-01

    Biodegradation of dissolved fluorene (Flu), phenanthrene (Ph) and pyrene (Py), three polycyclic aromatic hydrocarbons (PAHs), singly or as a mixture of the three, by two bacterial strains, MEBIC 5140 (Mycobacterium flavescens) and MEBIC 5141 (Mycobacterium scrofulaceum), as well as the effects of low molecular weight organic acids (LMWOAs), e.g. malic acid, citric acid and butyric acid on biodegradation of the three PAHs in mineral salts medium aqueous solution were investigated using a newly established dual-wavelength fluorimetric method. The results showed that biodegradation processes can be monitored simultaneously, quickly and simply by dual-wavelength fluorimetry. Both co-metabolism and inhibitory effects were found during the biodegradation of the three PAHs by MEBIC 5140 and MEBIC 5141. Positive effects of butyric acid and negative effects of citric acid on biodegradation of the three PAHs in a mixture were observed. - Biodegradation processes of dissolved multi-component PAHs in a mixture and effects of LMWOAs were investigated using a dual-wavelength fluorimetry.

  15. Formation of PAH-DNA adducts after in vivo and vitro exposure of rats and lung cells to different commercial carbon blacks.

    Science.gov (United States)

    Borm, Paul J A; Cakmak, Gonca; Jermann, Erich; Weishaupt, Christel; Kempers, Pascal; van Schooten, Frederik Jan; Oberdörster, Günter; Schins, Roel P F

    2005-06-01

    The current study was designed to test the possible release and bioavailability of polycyclic aromatic hydrocarbons (PAHs) from a set of commercial carbon blacks (CBs) as well as the ability of these PAHs to form bulky DNA adducts. In four commercial CBs (Printex 90, Sterling V, N330, Lampblack 101), leaching of PAH was examined through (1) release of parent PAHs in saline with or without surfactant, and (2) PAH adducts in lung epithelial cells (A549) or in rat lungs after exposure to two CBs (Printex 90, Sterling V) for 13 weeks (50 mg/m(3)). In vitro experiments were done with original and extracted particles, as well as organic extracts of CB in DMSO. As positive controls, B[a]P (0.03 microM) and a mixture of 16 PAHs (0.1 microM) were used. No leaching of PAHs was measured in saline or surfactant-containing saline. In vitro incubations with CB particles (30-300 microg/cm(2)) revealed no adduct spots except for Sterling V. However, the spot was not concentration dependent and remains unidentified. Lung DNA from rats after inhalation of Printex 90 or Sterling V showed no spots related to PAH-DNA adduct formation compared to sham-exposed rats. The results suggest that PAHs are very tightly bound to these CBs. Only using organic extracts or particles of low-surface Sterling V, with high PAH content, PAHs may become available to form PAH-DNA adducts. However, the in vitro conditions showing this effect will not be encountered in vivo and renders this mechanism in particle-induced lung cancer at in vivo exposures highly unlikely.

  16. Formation of PAH-DNA adducts after in vivo and vitro exposure of rats and lung cells to different commercial carbon blacks

    International Nuclear Information System (INIS)

    Borm, Paul J.A.; Cakmak, Gonca; Jermann, Erich; Weishaupt, Christel; Kempers, Pascal; Schooten, Frederik Jan van; Oberdoerster, Guenter; Schins, Roel P.F.

    2005-01-01

    Objective: The current study was designed to test the possible release and bioavailability of polycyclic aromatic hydrocarbons (PAHs) from a set of commercial carbon blacks (CBs) as well as the ability of these PAHs to form bulky DNA adducts. Methods: In four commercial CBs (Printex 90, Sterling V, N330, Lampblack 101), leaching of PAH was examined through (1) release of parent PAHs in saline with or without surfactant, and (2) PAH adducts in lung epithelial cells (A549) or in rat lungs after exposure to two CBs (Printex 90, Sterling V) for 13 weeks (50 mg/m 3 ). In vitro experiments were done with original and extracted particles, as well as organic extracts of CB in DMSO. As positive controls, B[a]P (0.03 μM) and a mixture of 16 PAHs (0.1 μM) were used. Results: No leaching of PAHs was measured in saline or surfactant-containing saline. In vitro incubations with CB particles (30-300 μg/cm 2 ) revealed no adduct spots except for Sterling V. However, the spot was not concentration dependent and remains unidentified. Lung DNA from rats after inhalation of Printex 90 or Sterling V showed no spots related to PAH-DNA adduct formation compared to sham-exposed rats. Conclusion: The results suggest that PAHs are very tightly bound to these CBs. Only using organic extracts or particles of low-surface Sterling V, with high PAH content, PAHs may become available to form PAH-DNA adducts. However, the in vitro conditions showing this effect will not be encountered in vivo and renders this mechanism in particle-induced lung cancer at in vivo exposures highly unlikely

  17. Biological treatment of PAH-contaminated sediments in a Sequencing Batch Reactor

    International Nuclear Information System (INIS)

    Chiavola, Agostina; Baciocchi, Renato; Gavasci, Renato

    2010-01-01

    The technical feasibility of a sequential batch process for the biological treatment of sediments contaminated by polycyclic aromatic hydrocarbons (PAHs) was evaluated through an experimental study. A bench-scale Sediment Slurry Sequencing Batch Reactor (SS-SBR) was fed with river sediments contaminated by a PAH mixture made by fluorene, anthracene, pyrene and crysene. The process performance was evaluated under different operating conditions, obtained by modifying the influent organic load, the feed composition and the hydraulic residence time. Measurements of the Oxygen Uptake Rates (OURs) provided useful insights on the biological kinetics occurring in the SS-SBR, suggesting the minimum applied cycle time-length of 7 days could be eventually halved, as also confirmed by the trend observed in the volatile solid and total organic carbon data. The removal efficiencies gradually improved during the SS-SBR operation, achieving at the end of the study rather constant removal rates above 80% for both 3-rings PAHs (fluorene and anthracene) and 4-ring PAHs (pyrene and crysene) for an inlet total PAH concentration of 70 mg/kg as dry weight (dw).

  18. Urban sprawl leaves its PAH signature

    Science.gov (United States)

    Van Metre, P.C.; Mahler, B.J.; Furlong, E.T.

    2000-01-01

    The increasing vehicle traffic associated with urban sprawl in the United States is frequently linked to degradation of air quality, but its effect on aquatic sediment is less well-recognized. This study evaluates trends in PAHs, a group of contaminants with multiple urban sources, in sediment cores from 10 reservoirs and lakes in six U.S. metropolitan areas. The watersheds chosen represent a range in degree and age of urbanization. Concentrations of PAHs in all 10 reservoirs and lakes increased during the past 20-40 years. PAH contamination of the most recently deposited sediment at all sites exceeded sediment-quality guidelines established by Environment Canada, in some cases by several orders of magnitude. These results add a new chapter to the story told by previous coring studies that reported decreasing concentrations of PAHs after reaching highs in the 1950s. Concurrent with the increase in concentrations is a change in the assemblage of PAHs that indicates the increasing trends are driven by combustion sources. The increase in PAH concentrations tracks closely with increases in automobile use, even in watersheds that have not undergone substantial changes in urban land-use levels since the 1970s.The increasing vehicle traffic associated with urban sprawl in the United States is frequently linked to degradation of air quality, but its effect on aquatic sediment is less well-recognized. This study evaluates trends in PAHs, a group of contaminants with multiple urban sources, in sediment cores from 10 reservoirs and lakes in six U.S. metropolitan areas. The watersheds chosen represent a range in degree and age of urbanization. Concentrations of PAHs in all 10 reservoirs and lakes increased during the past 20-40 years. PAH contamination of the most recently deposited sediment at all sites exceeded sediment-quality guidelines established by Environment Canada, in some cases by several orders of magnitude. These results add a new chapter to the story told by

  19. Effects of polycyclic aromatic hydrocarbons (PAHs) in environmental pollution on exogenous and oxidative DNA damage (EXPAH project): description of the population under study.

    Science.gov (United States)

    Taioli, Emanuela; Sram, Radim J; Garte, Seymour; Kalina, Ivan; Popov, Todor A; Farmer, Peter B

    2007-07-01

    The EXPAH project was a molecular epidemiology study whose aims were to evaluate the hypothesis that polycyclic aromatic hydrocarbons (PAHs) are a major source of genotoxic activities of organic mixtures associated with air pollution. Biomarkers of exposure, effects and susceptibility, and oxidative DNA damage were measured in three PAH-exposed populations from Prague (Czech Republic), Kosice (Slovakia) and Sofia (Bulgaria). Control populations were included from each city. In total 356 individuals were enrolled. A questionnaire was used to determine life style/dietary factors. Ambient air exposure was measured by stationary monitoring, and personal exposure monitoring was also carried out. The characteristics of the population are described in this paper together with their personal exposure to carcinogenic PAHs (c-PAHs). The dose of c-PAH exposure was found to vary between the occupationally exposed (e.g. policemen and bus drivers) and the control populations in each country, and also varied from country to country.

  20. SOA formation from photooxidation of naphthalene and methylnaphthalenes with m-xylene and surrogate mixtures

    Science.gov (United States)

    Chen, Chia-Li; Li, Lijie; Tang, Ping; Cocker, David R.

    2018-05-01

    SOA formation is not well predicted in current models in urban area. The interaction among multiple anthropogenic volatile organic compounds is essential for the SOA formation in the complex urban atmosphere. Secondary organic aerosol (SOA) from the photooxidation of naphthalene, 1-methylnaphthalene, and 2-methylnaphthalene as well as individual polycyclic aromatic hydrocarbons (PAHs) mixed with m-xylene or an atmospheric surrogate mixture was explored in the UCR CE-CERT environmental chamber under urban relevant low NOx and extremely low NOx (H2O2) conditions. Addition of m-xylene suppressed SOA formation from the individual PAH precursor. A similar suppression effect on SOA formation was observed during the surrogate mixture photooxidation suggesting the importance of gas-phase chemical reactivity to SOA formation. The SOA growth rate for different PAH-m-xylene mixtures was strongly correlated with initial [HO2]/[RO2] ratio but negatively correlated with initial m-xylene/NO ratio. Decreasing SOA formation was observed for increasing m-xylene/PAHs ratios and increasing initial m-xylene/NO ratio. The SOA chemical composition characteristics such as f44 versus f43, H/C ratio, O/C ratio, and the oxidation state of the carbon OSbarc were consistent with a continuously aging with the SOA exhibiting characteristics of both individual precursors. SOA formation from PAHs was also suppressed within an atmospheric surrogate mixture compared to the SOA formed from individual PAHs, indicating that atmospheric reactivity directly influences SOA formation from PAHs.

  1. Polysykliske aromatiske hydrokarboner (PAH) i fisk

    OpenAIRE

    Knutzen, J.

    1987-01-01

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

  2. Determination of polynuclear aromatic hydrocarbons (PAHs) in ...

    African Journals Online (AJOL)

    AJB SERVER

    2006-11-02

    Nov 2, 2006 ... Several water bodies in the Niger Delta region of Nigeria where extensive crude oil ..... hydrocarbons (PAHs) in fish from the Red Sea Coast of Yemem. ... smoked meat products and smoke flavouring food additives. J.

  3. Influence of heavy metals on the formation and the distribution behavior of PAH and PCDD/F during simulated fires.

    Science.gov (United States)

    Wobst, M; Wichmann, H; Bahadir, M

    2003-04-01

    Combustion experiments were performed with an artificial fire load (polystyrene and quartz powder) in a laboratory scale incinerator in the presence of gaseous HCl to simulate accidental fire conditions. The aim of this investigation was to trace back the alterations of the formation and the distribution behavior of PAH and PCDD/PCDF to the presence of CuO or a mixture of metal oxides (CdO, CuO, Fe(2)O(3), PbO, MoO(3), ZnO). The total amount of the 16 PAH target compounds was reduced by the factor of 5-9 when the mixture of metal oxides was present rather than merely CuO. PAH patterns as well as their distribution behavior were significantly influenced by these oxides. In general, transportation inside the installation was enhanced for most of the 16 analyzed PAH. Only fluorene and dibenzo[a,h]anthracene were transported to a smaller extent. In contrast to PAH, total concentrations of PCDD were increased by factor 9 and of PCDF by factor 10, respectively, when CuO was present. Adding the mixture of metal oxides resulted in an increase of PCDD by factor 14 and of PCDF by factor 7. CuO and the mixture of metal oxides had a different influence on the PCDD/F homologue patterns. For instance, the HxCDF to OCDF ratio after incineration without any metal oxide was 1 to 6, whereas addition of CuO or the mixture of the metal oxides shifted the HxCDF to OCDF ratios towards 1 to 40 or 1 to 17, respectively. Combustion along with CuO increased transportation of higher chlorinated PCDF congeners, whereas the mixture of the metal oxides caused a strong decrease of PCDF distribution throughout the system.

  4. Analysis of PAH in soil samples

    International Nuclear Information System (INIS)

    Haeufel, J.; Weisweiler, W.

    1994-01-01

    The supercritical fluid extraction of polycyclic aromatic hydrocarbons (PAH) from soil samples is described. Carbon dioxide mixed with a small amount of methanol is used for solvent. The results are compared with those obtained by a classical extraction method (that means with the use of organic liquids). The extracted PAH from both procedures can be separated by HPLC and analyzed with UV- and fluorescence detection. (orig.) [de

  5. PAH Spectroscopy: Past, Present and Future

    Science.gov (United States)

    Mattioda, Andrew

    2016-01-01

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

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

    International Nuclear Information System (INIS)

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

    2010-01-01

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

  7. Biomonitoring airborne parent and alkylated three-ring PAHs in the Greater Cologne Conurbation II: Regional distribution patterns

    International Nuclear Information System (INIS)

    Lehndorff, E.; Schwark, L.

    2009-01-01

    The spatial distribution of an important air pollutant class, three-ring polycyclic aromatic hydrocarbons and their derivatives (PAH-3), has been monitored for the Greater Cologne Conurbation (GCC) using pine needle as passive samplers. The GCC comprises one of the most heavily populated, trafficked, and industrialized regions in Germany. Here, 71 locations covering 3600 km 2 were sampled and, for the first time, isopleths maps constructed to investigate the regional variability in PAH-3 concentration and composition. The highest PAH-3 loads on needles (1000-1500 ng g -1 ) were detected downwind of three lignite fuelled power plants, followed by Cologne City (600-700 ng g -1 ) and smaller towns (400-600 ng g -1 ), whereas rural and forest regions yielded PAH-3 loads of 60-300 ng g -1 . PAH-3 ratios facilitated source reconciliation, with high dibenzothiophene versus retene values indicating lignite combustion and high 9/(9 + 1)-methylphenanthrene ratios depicting traffic emissions in inner cities. PAH-3 ratios depended on topography and outlined the heavily industrialized Rhine Valley, demonstrating atmospheric dispersal of PAH-3. - Regional high-resolution biomonitoring identified lignite combustion in power plants to dominate over urban traffic and other emission sources.

  8. From the Laboratory to Space: Neutral and Ionized PAHs in Translucent Interstellar Clouds

    Science.gov (United States)

    Salama, Farid; Galazutdinov, G.; Biennier, L.; Krelowski, J.

    2012-05-01

    We describe and discuss the laboratory experiments that were designed to test the proposal of relating the origin of some of the diffuse interstellar bands (DIBs) to neutral and ionized polycyclic aromatic hydrocarbons (PAHs) present in diffuse interstellar clouds. The spectra of several cold, isolated gas-phase PAH ions and neutral molecules have been measured using the COSmIC laboratory facility at NASA-Ames and are compared with an extensive set of astronomical spectra of reddened, early type stars. The COSmIC facility combines a supersonic free jet expansion with discharge plasma and high-sensitivity cavity ringdown spectroscopy to provide experimental conditions that closely mimic the interstellar conditions. This comparison provides - for the first time - accurate upper limits for the abundances of specific PAH molecules and ions along specific lines-of-sight. Something that is not attainable from infrared observations alone. The comparison of these unique laboratory data with high resolution, high S/N ratio astronomical observations leads to major findings regarding the column densities of the individual PAH molecules and ions that are probed in this survey and leads to clear and unambiguous conclusions regarding the expected abundances for PAHs of various sizes and charge states in these environments. This quantitative survey of neutral and ionized PAHs in the optical range opens the way for unambiguous quantitative searches of PAHs and complex organics in a variety of interstellar and circumstellar environments. Acknowledgements: F.S. acknowledges the support of the NASA’s Space Mission Directorate APRA Program. The authors are deeply grateful to the ESO archive as well as to the ESO staff members for their active support.

  9. Infrared spectra of interstellar deuteronated PAHs

    Science.gov (United States)

    Buragohain, Mridusmita; Pathak, Amit; Sarre, Peter

    2015-08-01

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

  10. Mutagenic hazards of complex polycyclic aromatic hydrocarbon mixtures in contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Lemieux, C.L.; Lambert, A.B.; Lundstedt, S.; Tysklind, M.; White, P.A. [Health Canada, Ottawa, ON (Canada). Safe Environment Program

    2008-04-15

    The objective of the present study was to evaluate hazard/risk assessment methods for complex environmental mixtures that involve a targeted, priority chemical approach based on the cumulative hazard/risk of known mixture components or analyses of sufficiently similar mixtures. Ten polycyclic aromatic hydrocarbon (PAH)-contaminated soils were separated into nonpolar and semipolar fractions, and both fractions elicited positive responses on the Salmonella reverse mutation assay. Targeted and nontargeted methods of hazard prediction routinely overestimated mutagenic activities for the nonpolar soil fractions, suggesting nonadditive interactions of PAHs in complex mixtures. This suggests that current risk assessment methods for complex mixtures may provide conservative estimates regarding soils contaminated with priority PAHs alone. Significant underestimations of total risk, however, will be obtained if the soils also contain unidentified PAHs as well as polycyclic aromatic compounds and related compounds that contribute to the total mutagenic activity. Furthermore, estimates of excess lifetime cancer risk associated with the nondietary ingestion of the PAH-contaminated soils studied here indicate that a traditional risk assessment model based on identified priority PAHs and an assumption of additivity generally underestimates the risk associated with the nonpolar soil fractions (in comparison to bioassay-derived risk estimates). Additional cancer risk may be associated with the more polar compounds that also are found at these contaminated sites and that rarely are included in the standard risk assessment methodology.

  11. Abundances of Neutral and Ionized PAH Along The Lines-of-Sight of Diffuse and Translucent Interstellar Clouds

    Science.gov (United States)

    Salama, Farid; Galazutdinov, Gazinur; Krewloski, Jacek; Biennier, Ludovic; Beletsky, Yuri; Song, In-Ok

    2013-01-01

    The spectra of neutral and ionized PAHs isolated in the gas phase at low temperature have been measured in the laboratory under conditions that mimic interstellar conditions and are compared with a set of astronomical spectra of reddened, early type stars. The comparisons of astronomical and laboratory data provide upper limits for the abundances of neutral PAH molecules and ions along specific lines-of-sight. Something that is not attainable from infrared observations. We present the characteristics of the laboratory facility (COSmIC) that was developed for this study and discuss the findings resulting from the comparison of the laboratory data with high resolution, high S/N ratio astronomical observations. COSmIC combines a supersonic jet expansion with discharge plasma and cavity ringdown spectroscopy and provides experimental conditions that closely mimic the interstellar conditions. The column densities of the individual PAH molecules and ions probed in these surveys are derived from the comparison of the laboratory data with high resolution, high S/N ratio astronomical observations. The comparisons of astronomical and laboratory data lead to clear conclusions regarding the expected abundances for PAHs in the interstellar environments probed in the surveys. Band profile comparisons between laboratory and astronomical spectra lead to information regarding the molecular structures and characteristics associated with the DIB carriers in the corresponding lines-of-sight. These quantitative surveys of neutral and ionized PAHs in the optical range open the way for quantitative searches of PAHs and complex organics in a variety of interstellar and circumstellar environments.

  12. Construction of PAH-degrading mixed microbial consortia by induced selection in soil.

    Science.gov (United States)

    Zafra, German; Absalón, Ángel E; Anducho-Reyes, Miguel Ángel; Fernandez, Francisco J; Cortés-Espinosa, Diana V

    2017-04-01

    Bioremediation of polycyclic aromatic hydrocarbons (PAHs)-contaminated soils through the biostimulation and bioaugmentation processes can be a strategy for the clean-up of oil spills and environmental accidents. In this work, an induced microbial selection method using PAH-polluted soils was successfully used to construct two microbial consortia exhibiting high degradation levels of low and high molecular weight PAHs. Six fungal and seven bacterial native strains were used to construct mixed consortia with the ability to tolerate high amounts of phenanthrene (Phe), pyrene (Pyr) and benzo(a)pyrene (BaP) and utilize these compounds as a sole carbon source. In addition, we used two engineered PAH-degrading fungal strains producing heterologous ligninolytic enzymes. After a previous selection using microbial antagonism tests, the selection was performed in microcosm systems and monitored using PCR-DGGE, CO 2 evolution and PAH quantitation. The resulting consortia (i.e., C1 and C2) were able to degrade up to 92% of Phe, 64% of Pyr and 65% of BaP out of 1000 mg kg -1 of a mixture of Phe, Pyr and BaP (1:1:1) after a two-week incubation. The results indicate that constructed microbial consortia have high potential for soil bioremediation by bioaugmentation and biostimulation and may be effective for the treatment of sites polluted with PAHs due to their elevated tolerance to aromatic compounds, their capacity to utilize them as energy source. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. A novel spectral resolution and simultaneous determination of multicomponent mixture of Vitamins B1, B6, B12, Benfotiamine and Diclofenac in tablets and capsules by derivative and MCR-ALS

    Science.gov (United States)

    Hegazy, Maha A.; Abdelwahab, Nada S.; Fayed, Ahmed S.

    2015-04-01

    A novel method was developed for spectral resolution and further determination of five-component mixture including Vitamin B complex (B1, B6, B12 and Benfotiamine) along with the commonly co-formulated Diclofenac. The method is simple, sensitive, precise and could efficiently determine the five components by a complementary application of two different techniques. The first is univariate second derivative method that was successfully applied for determination of Vitamin B12. The second is Multivariate Curve Resolution using the Alternating Least Squares method (MCR-ALS) by which an efficient resolution and quantitation of the quaternary spectrally overlapped Vitamin B1, Vitamin B6, Benfotiamine and Diclofenac sodium were achieved. The effect of different constraints was studied and the correlation between the true spectra and the estimated spectral profiles were found to be 0.9998, 0.9983, 0.9993 and 0.9933 for B1, B6, Benfotiamine and Diclofenac, respectively. All components were successfully determined in tablets and capsules and the results were compared to HPLC methods and they were found to be statistically non-significant.

  14. Polycyclic aromatic hydrocarbons (PAHs) skin permeation rates change with simultaneous exposures to solar ultraviolet radiation (UV-S).

    Science.gov (United States)

    Hopf, Nancy B; Spring, Philipp; Hirt-Burri, Nathalie; Jimenez, Silvia; Sutter, Benjamin; Vernez, David; Berthet, Aurelie

    2018-05-01

    Road construction workers are simultaneously exposed to two carcinogens; solar ultraviolet (UV-S) radiation and polycyclic aromatic hydrocarbons (PAHs) in bitumen emissions. The combined exposure may lead to photogenotoxicity and enhanced PAH skin permeation rates. Skin permeation rates (J) for selected PAHs in a mixture (PAH-mix) or in bitumen fume condensate (BFC) with and without UV-S co-exposures were measured with in vitro flow-through diffusion cells mounted with human viable skin and results compared. Possible biomarkers were explored. Js were greater with UV-S for naphthalene, anthracene, and pyrene in BFC (0.08-0.1 ng/cm 2 /h) compared to without (0.02-0.26 ng/cm 2 /h). This was true for anthracene, pyrene, and chrysene in the PAH-mix. Naphthalene and benzo(a)pyrene (BaP) in the PAH-mix had greater Js without (0.97-13.01 ng/cm 2 /h) compared to with UV-S (0.40-6.35 ng/cm 2 /h). Time until permeation (T lags ) in the PAH-mix were generally shorter compared to the BFC, and they ranged from 1 to 13 h. The vehicle matrix could potentially be the reason for this discrepancy as BFC contains additional not identified substances. Qualitative interpretation of p53 suggested a dose-response with UV-S, and somewhat with the co-exposures. MMP1, p65 and cKIT were not exploitable. Although not statistically different, PAHs permeate human viable skin faster with simultaneous exposures to UV. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Remediation of Soil and Ground Water Contaminated with PAH using Heat and Fe(II)-EDTA Catalyzed Persulfate Oxidation

    International Nuclear Information System (INIS)

    Nadim, Farhad; Huang, Kun-Chang; Dahmani, Amine M.

    2006-01-01

    demonstrated the feasibility of degrading PAHs in aqueous systems with persulfate oxidation. Additional tests are being conducted to evaluate the effectiveness of treating PAHs in soils and obtaining the rate of degradation of PAHs with persulfate oxidation.Two sets of laboratory experiments were conducted to evaluate the ability of sodium persulfate in oxidizing real world PAH-contaminated soils collected from a Superfund site in Connecticut. The first set of soil sample were treated only with persulfate and to the second batch, mixture of persulfate and Fe(II)-EDTA solutions were added. The results of the second test showed that within 24 hours, 75% to 100% of the initial concentrations of seven PAH compounds detected in the soil samples were degraded by sodium persulfate mixed with FE(II)-EDTA

  16. Grouting mixture

    Energy Technology Data Exchange (ETDEWEB)

    Klyusov, A A; Bakshutov, V S; Kulyavtsev, V A

    1980-10-23

    A grouting mixture is proposed for low-temperature boreholes. The mixture contains cement, beta gypsum polyhydrate, and calcium chloride, so as to increase the water resistance and strength properties of expanding brick at conditions from 20 to -5/sup 0/ C, the components are in the following ratios: (by wt.-%): cement, 77.45-88.06; beta gypsum polyhydrate, 9.79-19.36; calcium chloride, 2.15-3.19. Grouting mortar for cold boreholes serves as the cement.

  17. Phyto remediation of PAH contaminated soil

    International Nuclear Information System (INIS)

    Petruzzelli, G.; Pedron, F.; Barbafieri, M.; Cervelli, St.; Vigna Guidi, G.

    2005-01-01

    Phyto-remediation may enhance degradation of organic compounds promoting an adequate substrate for microbial growth. The aim of this work was to evaluate the efficiency of two plant species, Lupinus albus and Zea mais, in the bio-remediation of a PAH contaminated soil. This soil has been collected in a contaminated industrial area in Italy characterized by PAH concentrations up to 16000 mg/Kg. Microcosms experiments were carried out by planting Lupinus albus and Zea mais in the polluted soil; controls without plants were run separately. Growing period lasted by three months. Plants favoured PAH biodegradation by percentages of 32% with Lupinus albus and 22% with Zea mais, with respect to non vegetated microcosms. (authors)

  18. Surfactant-enhanced bioremediation of PAH- and PCB-contaminated soils

    International Nuclear Information System (INIS)

    Ghosh, M.M.; Yeom, I.T.; Shi, Z.; Cox, C.D.; Robinson, K.G.

    1995-01-01

    The role of surfactants in the desorption of soil-bound polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) was investigated. The solubilization of individual PAHs in an extract of a weathered, coal tar-contaminated soil containing a mixture of PAHs and other petroleum derivatives was found to be significantly less than that for pure compounds. Batch soil washing with Triton X-100 (a commercial, nonionic alkyl phenol ethoxylate) was found to increase the effective diffusion rate of PAHs from the contaminated soil by four orders of magnitude compared to that obtained by gas purging when the results were analyzed using a radial diffusion model. At concentrations of up to 24 times its critical micelle concentration (CMC), Triton X-100 did not seem to enhance hydrocarbon degradation in the coal tar-contaminated soil; however, the biosurfactant rhamnolipid R1, at a concentration of 50x CMC, increased the rate of mineralization of 4,4'-chlorinated biphenyl mobilized from a laboratory-contaminated soil by more than 60 times

  19. Further validation of the HPCD-technique for the evaluation of PAH microbial availability in soil

    International Nuclear Information System (INIS)

    Doick, Kieron J.; Clasper, Paula J.; Urmann, Karina; Semple, Kirk T.

    2006-01-01

    There is currently considerable scientific interest in finding a chemical technique capable of predicting bioavailability; non-exhaustive extraction techniques (NEETs) offer such potential. Hydroxypropyl-beta-cyclodextrin (HPCD), a NEET, is further validated through the investigation of concentration ranges, differing soil types, and the presence of co-contaminants. This is the first study to demonstrate the utility of the HPCD-extraction technique to predict the microbial availability to phenanthrene across a wide concentration range and independent of soil-contaminant contact time (123 d). The efficacy of the HPCD-extraction technique for the estimation of PAH microbial availability in soil is demonstrated in the presence of co-contaminants that have been aged for the duration of the experiment together in the soil. Desorption dynamics are compared in co-contaminant and single-PAH contaminated spiked soils to demonstrate the occurrence of competitive displacement. Overall, a single HPCD-extraction technique proved accurate and reproducible for the estimation of PAH bioavailability from soil. - HPCD extractions can determine the microbial availability of PAHs in mixtures and over a range of concentrations

  20. Measurement of personal exposure to volatile organic compounds and particle associated PAH in three UK regions.

    Science.gov (United States)

    Saborit, Juana Mari Delgado; Aquilina, Noel J; Meddings, Claire; Baker, Stephen; Vardoulakis, Sotiris; Harrison, Roy M

    2009-06-15

    Personal exposures to 15 volatile organic compounds (VOC) and 16 polycyclic aromatic hydrocarbons (PAH) of 100 adult nonsmokers living in three UK areas, namely London, West Midlands, and rural South Wales, were measured using an actively pumped sampler carried around by the volunteers for 5/1 (VOC/PAH) consecutive 24-h periods, following their normal lifestyle. Results from personal exposure measurements categorized by geographical location, type of dwelling, and exposure to environmental tobacco smoke (ETS) are presented. The average personal exposure concentration to benzene, 1,3-butadiene, and benzo(a)pyrene representing the main carcinogenic components of the VOC and PAH mixture were 2.2 +/- 2.5 microg/m3, 0.4 +/- 0.7 microg/m3, and 0.3 +/- 0.7 ng/m3 respectively. The association of a number of generic factors with personal exposure concentrations was investigated, including first-line property, traffic, the presence of an integral garage, and ETS. Only living in houses with integral garages and being exposed to ETS were identified as unequivocal contributors to VOC personal exposure, while only ETS had a clear effect upon PAH personal exposures. The measurements of personal exposures were compared with health-based European and UK air quality guidelines, with some exceedences occurring. Activities contributing to high personal exposures included the use of a fireplace in the home, ETS exposure, DIY (i.e., construction and craftwork activities), and photocopying, among others.

  1. Effect of rhamnolipids on the uptake of PAHs by ryegrass

    International Nuclear Information System (INIS)

    Zhu Lizhong; Zhang Ming

    2008-01-01

    A hydroponic experiment was conducted to investigate the effect of rhamnolipids, a biosurfactant, on the uptake of polycyclic aromatic hydrocarbons (PAHs) by ryegrass. Results showed that rhamnolipids could enhance the uptake of PAHs by ryegrass roots. With increasing concentration of rhamnolipids, the PAH content in ryegrass roots initially increased and then decreased, while the PAH content in ryegrass shoots did not change. Batch studies also showed that the sorption of phenanthrene by fresh ryegrass roots was dependent on rhamnolipid concentration and showed the same trends as the uptake experiment. The increase of permeability of ryegrass root cells with the increase of rhamnolipid concentration may lead to the initial enhancement of PAH content in ryegrass roots, and the decrease of PAH adsorption onto the root surface with further increase of rhamnolipids led to the decrease of PAH content in ryegrass roots. - Rhamnolipids, a biosurfactant, can promote the uptake of PAHs by ryegrass, which indicates a potential application of surfactant-enhanced phytoremediation

  2. Effect of rhamnolipids on the uptake of PAHs by ryegrass

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Lizhong [Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang 310028 (China); Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, Zhejiang University, Hangzhou, Zhejiang 310029 (China)], E-mail: zlz@zju.edu.cn; Zhang Ming [Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang 310028 (China)], E-mail: zhangming@zju.edu.cn

    2008-11-15

    A hydroponic experiment was conducted to investigate the effect of rhamnolipids, a biosurfactant, on the uptake of polycyclic aromatic hydrocarbons (PAHs) by ryegrass. Results showed that rhamnolipids could enhance the uptake of PAHs by ryegrass roots. With increasing concentration of rhamnolipids, the PAH content in ryegrass roots initially increased and then decreased, while the PAH content in ryegrass shoots did not change. Batch studies also showed that the sorption of phenanthrene by fresh ryegrass roots was dependent on rhamnolipid concentration and showed the same trends as the uptake experiment. The increase of permeability of ryegrass root cells with the increase of rhamnolipid concentration may lead to the initial enhancement of PAH content in ryegrass roots, and the decrease of PAH adsorption onto the root surface with further increase of rhamnolipids led to the decrease of PAH content in ryegrass roots. - Rhamnolipids, a biosurfactant, can promote the uptake of PAHs by ryegrass, which indicates a potential application of surfactant-enhanced phytoremediation.

  3. Model-based experimental design for assessing effects of mixtures of chemicals

    NARCIS (Netherlands)

    Baas, J.; Stefanowicz, A.M.; Klimek, B.; Laskowski, R.; Kooijman, S.A.L.M.

    2010-01-01

    We exposed flour beetles (Tribolium castaneum) to a mixture of four poly aromatic hydrocarbons (PAHs). The experimental setup was chosen such that the emphasis was on assessing partial effects. We interpreted the effects of the mixture by a process-based model, with a threshold concentration for

  4. Impact of clay mineral on air oxidation of PAH-contaminated soils.

    Science.gov (United States)

    Biache, Coralie; Kouadio, Olivier; Lorgeoux, Catherine; Faure, Pierre

    2014-09-01

    This work investigated the impact of a clay mineral (bentonite) on the air oxidation of the solvent extractable organic matters (EOMs) and the PAHs from contaminated soils. EOMs were isolated from two coking plant soils and mixed with silica sand or bentonite. These samples, as well as raw soils and bentonite/soil mixtures, were oxidized in air at 60 and 100 °C for 160 days. Mineralization was followed by measuring the CO2 produced over the experiments. EOM, polycyclic aromatic compound (PAC), including PAH, contents were also determined. Oxidation led to a decrease in EOM contents and PAH concentrations, these diminutions were enhanced by the presence of bentonite. Transfer of carbon from EOM to insoluble organic matter pointed out a condensation phenomenon leading to a stabilization of the contamination. Higher mineralization rates, observed during the oxidation of the soil/bentonite mixtures, seem to indicate that this clay mineral had a positive influence on the transformation of PAC into CO2.

  5. A PAH growth mechanism and synergistic effect on PAH formation in counterflow diffusion flames

    KAUST Repository

    Wang, Yu; Raj, Abhijeet Dhayal; Chung, Suk-Ho

    2013-01-01

    was tested for ethylene premixed flames at low (20torr) and atmospheric pressures by comparing experimentally observed species concentrations with those of the computed ones for small chemical species and PAHs. As compared to several existing mechanisms

  6. Polycyclic Aromatic Hydrocarbons (PAHs) Levels in Two ...

    African Journals Online (AJOL)

    Polycyclic aromatic hydrocarbons (PAHs) concentrations were measured by gas chromatography with flame ionization detector (GC/FID) in two fish species, Sardinella maderensis (Flat sardinella) and Galeoides decadactylus (Lesser African threadfin or Shine-nose or Common threadfin) from Ghanaian coastal waters and ...

  7. Determination of polynuclear aromatic hydrocarbons (PAHs) in ...

    African Journals Online (AJOL)

    AJB SERVER

    2006-11-02

    Nov 2, 2006 ... (PAHs) in selected water bodies in the Niger Delta. Chimezie Anyakora and ... production, foundries), transportation, burning (e.g. forest, straw, agriculture ..... the Red Sea Coast of Yemen (DouAbul et al., 1997), a comparable ...

  8. Identification of PAH Isomeric Structure in Cosmic Dust Analogs: The AROMA Setup

    Energy Technology Data Exchange (ETDEWEB)

    Sabbah, Hassan; Bonnamy, Anthony; Joblin, Christine [Université de Toulouse, UPS-OMP, Institut de Recherche en Astrophysique et Planétologie, 9 avenue du Colonel Roche, 31028 Toulouse Cedex 4 (France); Papanastasiou, Dimitris [Fasmatech Science + Technology, Athens, GR (Greece); Cernicharo, Jose; Martín-Gago, Jose-Angel, E-mail: christine.joblin@irap.omp.eu [Instituto de Ciencia de Materiales de Madrid, Sor Juana Inés de la Cruz, 3, Cantoblanco, E-28049 Madrid (Spain)

    2017-07-01

    We developed a new analytical experimental setup called AROMA (Astrochemistry Research of Organics with Molecular Analyzer) that combines laser desorption/ionization techniques with ion trap mass spectrometry. We report here on the ability of the apparatus to detect aromatic species in complex materials of astrophysical interest and characterize their structures. A limit of detection of 100 femto-grams has been achieved using pure polycyclic aromatic hydrocarbon (PAH) samples, which corresponds to 2 × 10{sup 8} molecules in the case of coronene (C{sub 24}H{sub 12}). We detected the PAH distribution in the Murchison meteorite, which is made of a complex mixture of extraterrestrial organic compounds. In addition, collision induced dissociation experiments were performed on selected species detected in Murchison, which led to the first firm identification of pyrene and its methylated derivatives in this sample.

  9. Seasonal Variations and Sources of Airborne Polycyclic Aromatic Hydrocarbons (PAHs in Chengdu, China

    Directory of Open Access Journals (Sweden)

    Ju Yang

    2018-02-01

    Full Text Available The concentrations of polycyclic aromatic hydrocarbons (PAHs in the air of Chengdu, a southwest city of China, were determined from March 2015 to February 2016. Here, two diagnostic ratios (DR were determined and a principal component analysis/multiple linear regression (PCA/MLR analysis was performed to identify the sources of PAHs during the four seasons. The gaseous and particle phase samples were analyzed separately. The sampled air had a gas-to particle ratio of 4.21, and between 18.7% and 31.3% of the total detected PAHs were found in the particulate phase. The total concentration of all 16-PAHs combined (gas + particles varied from 176.94 in summer to 458.95 ng·m−3 in winter, with a mean of 300.35 ± 176.6 ng·m−3. In the gas phase, phenanthrene(Phe was found at the highest concentrations in all four seasons, while benzo[b]fluoranthene(BbF and (in winter chrysene(Chr were the highest in the particle phase. The DR of Fluroanthene (Flua/(Flua + Pyrene (Pyr was higher in the gas phase than in the particle phase, while the Indeno[1,2,3-cd]pyrene(IcdP/(IcdP + Benzo[ghi]perylene (BghiP ratio was more variable in the gas than that in the particle phase. The main sources for both phases were a mixture of liquid fossil fuel combustion and the burning of biomass and coal, with clear seasonal variation. Principal Component Analysis/Multiple Linear Regression (PCA/MLR analysis identified the main PAH sources as coal burning (52% with motor vehicle exhaust and coke (48% in spring; coal (52%, coke (21%, and motor vehicle exhaust (27% in summer; coal (47%, vehicle exhaust (34%, and coke (19% in autumn; and coal (58% and vehicle exhaust (42% in winter.

  10. Culture-dependent and -independent approaches establish the complexity of a PAH-degrading microbial consortium

    Energy Technology Data Exchange (ETDEWEB)

    Vinas, M.; Sabate, J.; Solanas, A.M. [Barcelona Univ., Barcelona (Spain). Dept. of Microbiology; Guasp, C.; Lalucat, J. [Illes Balears Univ., Palma de Mallorca (Spain). Dept. of Biology

    2005-11-15

    Microbial consortia are used in the decontamination of polluted environmental sites. A microbial consortium obtained by batch enrichment culture is a closed system with controlled conditions in which micro-organisms with a potentially high growth rate are selected and become dominant. The aim of this study was to identify the members of consortium AM, in which earlier batch enrichment work had shown high biodegradation rates of the aromatic fraction of polycyclic aromatic hydrocarbon (PAH). The AM consortium was obtained by sequential enrichment in liquid culture with a PAH mixture of 3- and 4- ringed PAHs as the sole source of carbon and energy. The consortium was examined using a triple approach method based on various cultivation strategies, denaturing gradient electrophoresis (DGGE) and the screening of 16S and 18S rRNA gene clone libraries. Eleven different sequences by culture-dependent techniques and 7 by both DGGE and clone libraries were obtained, yielding 19 different microbial components. Proteobacteria were the dominant group, representing 83 per cent of the total, while the Cytophaga-Flexibactor-Bacteroides group (CFB) was 11 per cent, and Ascomycota fungi were 6 per cent. It was determined that {beta}-Proteobacteria were predominant in the DGGE and clone library methods, whereas they were a minority in culturable strains. The highest diversity and number of noncoincident sequences was achieved by the cultivation method that showed members of the {alpha},{beta}, and {gamma}-Proteobacteria, CFB bacterial group, and Ascomycota fungi. Only 6 of the 11 strains isolated showed PAH-degrading capability. The bacterial strain (AMS7) and the fungal strain (AMF1) achieved the greatest PAH depletion. Results indicated that polyphasic assessment is necessary for a proper understanding of the composition of a microbial consortium. It was concluded that microbial consortia are more complex than previously realized. 54 refs., 3 tabs., 3 figs.

  11. Removal of polycyclic aromatic hydrocarbons in soil spiked with model mixtures of petroleum hydrocarbons and heterocycles using biosurfactants from Rhodococcus ruber IEGM 231.

    Science.gov (United States)

    Ivshina, Irina; Kostina, Ludmila; Krivoruchko, Anastasiya; Kuyukina, Maria; Peshkur, Tatyana; Anderson, Peter; Cunningham, Colin

    2016-07-15

    Removal of polycyclic aromatic hydrocarbons (PAHs) in soil using biosurfactants (BS) produced by Rhodococcus ruber IEGM 231 was studied in soil columns spiked with model mixtures of major petroleum constituents. A crystalline mixture of single PAHs (0.63g/kg), a crystalline mixture of PAHs (0.63g/kg) and polycyclic aromatic sulfur heterocycles (PASHs), and an artificially synthesized non-aqueous phase liquid (NAPL) containing PAHs (3.00g/kg) dissolved in alkanes C10-C19 were used for spiking. Percentage of PAH removal with BS varied from 16 to 69%. Washing activities of BS were 2.5 times greater than those of synthetic surfactant Tween 60 in NAPL-spiked soil and similar to Tween 60 in crystalline-spiked soil. At the same time, amounts of removed PAHs were equal and consisted of 0.3-0.5g/kg dry soil regardless the chemical pattern of a model mixture of petroleum hydrocarbons and heterocycles used for spiking. UV spectra for soil before and after BS treatment were obtained and their applicability for differentiated analysis of PAH and PASH concentration changes in remediated soil was shown. The ratios A254nm/A288nm revealed that BS increased biotreatability of PAH-contaminated soils. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Recreating the seawater mixture composition of HOCs in toxicity tests with Artemia franciscana by passive dosing

    Energy Technology Data Exchange (ETDEWEB)

    Rojo-Nieto, E., E-mail: elisa.rojo@uca.es [Andalusian Centre of Marine Science and Technology (CACYTMAR), Department of Environmental Technologies, University of Cadiz, 11510 Puerto Real (Spain); Smith, K.E.C. [Department of Environmental Science, Aarhus University, DK-4000 Roskilde (Denmark); Perales, J.A. [Andalusian Centre of Marine Science and Technology (CACYTMAR), Department of Environmental Technologies, University of Cadiz, 11510 Puerto Real (Spain); Mayer, P. [Department of Environmental Science, Aarhus University, DK-4000 Roskilde (Denmark)

    2012-09-15

    The toxicity testing of hydrophobic organic compounds (HOCs) in aquatic media is generally challenging, and this is even more problematic for mixtures. The hydrophobic properties of these compounds make them difficult to dissolve, and subsequently to maintain constant exposure concentrations. Evaporative and sorptive losses are highly compound-specific, which can alter not only total concentrations, but also the proportions between the compounds in the mixture. Therefore, the general aim of this study was to explore the potential of passive dosing for testing the toxicity of a PAH mixture that recreates the mixture composition found in seawater from a coastal area of Spain, the Bay of Algeciras. First, solvent spiking and passive dosing were compared for their suitability to determine the acute toxicity to Artemia franciscana nauplii of several PAHs at their respective solubility limits. Second, passive dosing was applied to recreate the seawater mixture composition of PAHs measured in a Spanish monitoring program, to test the toxicity of this mixture at different levels. HPLC analysis was used to confirm the reproducibility of the dissolved exposure concentrations for the individual PAHs and mixtures. This study shows that passive dosing has some important benefits in comparison with solvent spiking for testing HOCs in aquatic media. These include maintaining constant exposure concentrations, leading to higher reproducibility and a relative increase in toxicity. Passive dosing is also able to faithfully reproduce real mixtures of HOCs such as PAHs, in toxicity tests, reproducing both the levels and proportions of the different compounds. This provides a useful approach for studying the toxicity of environmental mixtures of HOCs, both with a view to investigating their toxicity but also for determining safety factors before such mixtures result in detrimental effects.

  13. Distributions and Concentrations of PAHs in Hong Kong Soils

    International Nuclear Information System (INIS)

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

    2006-01-01

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

  14. Simultaneous determination of intestinal permeability and potential drug interactions of complex mixtures using Caco-2 cells and high-resolution mass spectrometry: Studies with Rauwolfia serpentina extract.

    Science.gov (United States)

    Flynn, Thomas J; Vohra, Sanah N

    2018-06-25

    Caco-2 cells are a commonly used model for estimating the intestinal bioavailability of single chemical entity pharmaceuticals. Caco-2 cells, when induced with calcitriol, also express other biological functions such as phase I (CYP) and phase II (glucuronosyltransferases) drug metabolizing enzymes which are relevant to drug-supplement interactions. Intestinal bioavailability is an important factor in the overall safety assessment of products consumed orally. Foods, including herbal dietary supplements, are complex substances with multiple chemical components. Because of potential interactions between components of complex mixtures, more reliable safety assessments can be obtained by studying the commercial products "as consumed" rather than by testing individual chemical components one at a time. The present study evaluated the apparent intestinal permeability (P app ) of a model herbal extract, Rauwolfia serpentina, using both whole plant extracts and the individual purified Rauwolfia alkaloids. All test compounds, endpoint substrates, and their metabolites were quantified using liquid chromatography and high-resolution mass spectrometry. The P app values for individual Rauwolfia alkaloids were comparable whether measured individually or as components of the complete extract. Both Rauwolfia extract and all individual Rauwolfia alkaloids except yohimbine inhibited CYP3A4 activity (midazolam 1'-hydroxylation). Both Rauwolfia extract and all individual Rauwolfia alkaloids except corynanthine and reserpic acid significantly increased glucuronosyltransferase activity (glucuronidation of 4-methylumbelliferone). The positive control, ketoconazole, significantly inhibited both CYP3A4 and glucuronosyltransferase activities. These findings suggest that the Caco-2 assay is capable of simultaneously identifying both bioavailability and potentially hazardous intestinal drug-supplement interactions in complex mixtures. Published by Elsevier B.V.

  15. Explicit Cloud Nucleation from Arbitrary Mixtures of Aerosol Types and Sizes Using an Ultra-Efficient In-Line Aerosol Bin Model in High-Resolution Simulations of Hurricanes

    Science.gov (United States)

    Walko, R. L.; Ashby, T.; Cotton, W. R.

    2017-12-01

    The fundamental role of atmospheric aerosols in the process of cloud droplet nucleation is well known, and there is ample evidence that the concentration, size, and chemistry of aerosols can strongly influence microphysical, thermodynamic, and ultimately dynamic properties and evolution of clouds and convective systems. With the increasing availability of observation- and model-based environmental representations of different types of anthropogenic and natural aerosols, there is increasing need for models to be able to represent which aerosols nucleate and which do not in supersaturated conditions. However, this is a very complex process that involves competition for water vapor between multiple aerosol species (chemistries) and different aerosol sizes within each species. Attempts have been made to parameterize the nucleation properties of mixtures of different aerosol species, but it is very difficult or impossible to represent all possible mixtures that may occur in practice. As part of a modeling study of the impact of anthropogenic and natural aerosols on hurricanes, we developed an ultra-efficient aerosol bin model to represent nucleation in a high-resolution atmospheric model that explicitly represents cloud- and subcloud-scale vertical motion. The bin model is activated at any time and location in a simulation where supersaturation occurs and is potentially capable of activating new cloud droplets. The bins are populated from the aerosol species that are present at the given time and location and by multiple sizes from each aerosol species according to a characteristic size distribution, and the chemistry of each species is represented by its absorption or adsorption characteristics. The bin model is integrated in time increments that are smaller than that of the atmospheric model in order to temporally resolve the peak supersaturation, which determines the total nucleated number. Even though on the order of 100 bins are typically utilized, this leads only

  16. Evaluation of PAH and PCB in soil

    International Nuclear Information System (INIS)

    Hein, D.; Delschen, T.

    1994-01-01

    The soil data obtained should be regarded as provisional, as there is still insufficient knowledge on the influence of accompanying substances such as organic solvents on the transfer behaviour and mobility of the soil pollutants under consideration. Moreover, the significance of metabolic processes in soils and plants is largely still unknown. There are no generally accepted standards for BCB and PAH analysis in soil and plants. The diversity in methods applied has led to widely disparate results. The data situation for PAH is so heterogeneous as to allow test results to be derived solely for benzo[a]pyrene. It will be a task for the future to clarify the extent to which other substances must be taken into account here, e.g., with respect to toxicity and availability. (orig.) [de

  17. Polycyclic aromatic hydrocarbons (PAHs) in yogurt samples.

    Science.gov (United States)

    Battisti, Chiara; Girelli, Anna Maria; Tarola, Anna Maria

    2015-01-01

    The concentrations and distributions of major polycyclic aromatic hydrocarbons (PAHs) were determined in 20 kinds of yogurt specimens collected from Italian supermarkets using reversed phase high-performance liquid chromatography equipped with fluorescence detection. The method was validated by determination of recovery percentages, precision (repeatability) and sensitivity (limits of detection) with yogurt samples fortified at 0.25, 0.5 and 1 µg/kg concentration levels. The recovery of 13 PAHs, with the exception of naphthalene and acenaphthene, ranged from 61% to 130% and from 60% to 97% at all the levels for yogurts with low (0.1%) and high (3.9%) fat content, respectively. The method is repeatable with relative standard deviation values yogurts with low and high fats were compared.

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

    Science.gov (United States)

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

    2014-05-01

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

  19. PAH exposure levels in mudpuppy (amphibian)

    Energy Technology Data Exchange (ETDEWEB)

    Trudeau, F; Maisonneuve, F [Environment Canada, Canadian Wildlife Service, Hull, PQ (Canada); Gendron, A D [Quebec Univ., Montreal, PQ (Canada); Bishop, C A [Environment Canada, Canada Centre for Inland Waters, Burlington, ON (Canada)

    1999-12-31

    The presence of PAHs in the environment is of great concern because of the mutagenic, teratogenic and carcinogenic properties of the metabolites produced in exposed organisms. In recent years, exposure of fish to PAHs was demonstrated by the detection of pyrene-type metabolites in bile, using synchronous fluorescence spectrometry (SFS), which offers a rapid screening tool to estimate recent exposure to PAHs. In this experiment, the SFS technique was applied to mudpuppy (Necturus maculosus), a benthic carnivorous salamander found in the lakes and rivers of northeastern America, susceptible to the chronic effects of contaminants accumulated through its diet and through its contact with the contaminated sediment. Samples were taken from a variety of locations (Akwesasne River, Batiscan River, in the St.-Lawrence River System, Des Prairies River and Quesnel Bay in the Ottawa River System, Wolfe Island, Long Point and the Detroit River in the Great Lakes Basin). Results of the examination showed that mud puppies collected from the Detroit River had, by far, the highest concentrations of biliary 1-hydroxy pyrene (798 ng/ml), compared to 84 ng/ml, or less, in other animals in the sample.

  20. PAH partitioning in a toxicity exposure chamber

    International Nuclear Information System (INIS)

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

    2003-01-01

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

  1. Research on the influence of anaerobic stabilization of various dairy sewage sludge on biodegradation of polycyclic aromatic hydrocarbons PAHs with the use of effective microorganisms

    International Nuclear Information System (INIS)

    Boruszko, Dariusz

    2017-01-01

    Sewage sludge was taken from a dairy WWTP belonging to Mlekovita Cooperative in Wysokie Mazowieckie. There were excess sludge, flotation sludge and a mixture of excess and flotation sludge from pre-treatment of dairy sewage. The initial content of 16 PAHs in excess sludge before fermentation was approximately 689 µg·kg −1 in dry mass, whereas in post-flotation sludge (which constituted around 30% of raw sludge) it was approximately 95 µg·kg −1 in dry mass. A mixture of excess and flotation sludge had the content of 497,7 µg·kg −1 in dry mass. Through comparison of particular hydrocarbons content in raw sewage sludge to the total PAHs content, it was shown that tricyclic compounds, which constituted 46,3% of the PAHs sum (excess sludge), and tetracyclic compounds, which constituted 60,0% of the PAHs sum (flotation sludge), were the dominating fractions. In the sludge subjected to fermentation in reactors with mixed sludge and surplus activated sludge, the general trend of the course of changes in concentrations of PAHs was similar. Both in the sludge inoculated with EM and in that not inoculated with EM, a significant increase in the total PAHs contents was observed in the first fermentation phase (acidic fermentation) after 7 days of the process. Addition of EM into the sludge did not prevent the PAHs release, and therefore higher concentrations of PAHs sum were recorded during the hydrolysis stage than in sludge before fermentation. A decrease in the sum of PAHs was observed after 2 weeks of fermentation in relation to the quantity observed after 1 week of fermentation (except from post-flotation sludge). In the following weeks, there was further decrease in the concentration of the 16 PAHs sum in all sludge types. However, in sludge without EM inoculation, it was lower than in sludge with EM inoculation. The loss of the majority of tested hydrocarbons was reported in the final phase of fermentation. - Highlights: • The influence of applying

  2. Research on the influence of anaerobic stabilization of various dairy sewage sludge on biodegradation of polycyclic aromatic hydrocarbons PAHs with the use of effective microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Boruszko, Dariusz, E-mail: d.boruszko@pb.edu.pl

    2017-05-15

    Sewage sludge was taken from a dairy WWTP belonging to Mlekovita Cooperative in Wysokie Mazowieckie. There were excess sludge, flotation sludge and a mixture of excess and flotation sludge from pre-treatment of dairy sewage. The initial content of 16 PAHs in excess sludge before fermentation was approximately 689 µg·kg{sup −1} in dry mass, whereas in post-flotation sludge (which constituted around 30% of raw sludge) it was approximately 95 µg·kg{sup −1} in dry mass. A mixture of excess and flotation sludge had the content of 497,7 µg·kg{sup −1} in dry mass. Through comparison of particular hydrocarbons content in raw sewage sludge to the total PAHs content, it was shown that tricyclic compounds, which constituted 46,3% of the PAHs sum (excess sludge), and tetracyclic compounds, which constituted 60,0% of the PAHs sum (flotation sludge), were the dominating fractions. In the sludge subjected to fermentation in reactors with mixed sludge and surplus activated sludge, the general trend of the course of changes in concentrations of PAHs was similar. Both in the sludge inoculated with EM and in that not inoculated with EM, a significant increase in the total PAHs contents was observed in the first fermentation phase (acidic fermentation) after 7 days of the process. Addition of EM into the sludge did not prevent the PAHs release, and therefore higher concentrations of PAHs sum were recorded during the hydrolysis stage than in sludge before fermentation. A decrease in the sum of PAHs was observed after 2 weeks of fermentation in relation to the quantity observed after 1 week of fermentation (except from post-flotation sludge). In the following weeks, there was further decrease in the concentration of the 16 PAHs sum in all sludge types. However, in sludge without EM inoculation, it was lower than in sludge with EM inoculation. The loss of the majority of tested hydrocarbons was reported in the final phase of fermentation. - Highlights: • The influence of

  3. Analyses of polycyclic aromatic hydrocarbon (PAH) and chiral-PAH analogues-methyl-β-cyclodextrin guest-host inclusion complexes by fluorescence spectrophotometry and multivariate regression analysis.

    Science.gov (United States)

    Greene, LaVana; Elzey, Brianda; Franklin, Mariah; Fakayode, Sayo O

    2017-03-05

    The negative health impact of polycyclic aromatic hydrocarbons (PAHs) and differences in pharmacological activity of enantiomers of chiral molecules in humans highlights the need for analysis of PAHs and their chiral analogue molecules in humans. Herein, the first use of cyclodextrin guest-host inclusion complexation, fluorescence spectrophotometry, and chemometric approach to PAH (anthracene) and chiral-PAH analogue derivatives (1-(9-anthryl)-2,2,2-triflouroethanol (TFE)) analyses are reported. The binding constants (K b ), stoichiometry (n), and thermodynamic properties (Gibbs free energy (ΔG), enthalpy (ΔH), and entropy (ΔS)) of anthracene and enantiomers of TFE-methyl-β-cyclodextrin (Me-β-CD) guest-host complexes were also determined. Chemometric partial-least-square (PLS) regression analysis of emission spectra data of Me-β-CD-guest-host inclusion complexes was used for the determination of anthracene and TFE enantiomer concentrations in Me-β-CD-guest-host inclusion complex samples. The values of calculated K b and negative ΔG suggest the thermodynamic favorability of anthracene-Me-β-CD and enantiomeric of TFE-Me-β-CD inclusion complexation reactions. However, anthracene-Me-β-CD and enantiomer TFE-Me-β-CD inclusion complexations showed notable differences in the binding affinity behaviors and thermodynamic properties. The PLS regression analysis resulted in square-correlation-coefficients of 0.997530 or better and a low LOD of 3.81×10 -7 M for anthracene and 3.48×10 -8 M for TFE enantiomers at physiological conditions. Most importantly, PLS regression accurately determined the anthracene and TFE enantiomer concentrations with an average low error of 2.31% for anthracene, 4.44% for R-TFE and 3.60% for S-TFE. The results of the study are highly significant because of its high sensitivity and accuracy for analysis of PAH and chiral PAH analogue derivatives without the need of an expensive chiral column, enantiomeric resolution, or use of a polarized

  4. A framework for the use of single-chemical transcriptomics data in predicting the hazards associated with complex mixtures of polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Labib, Sarah; Williams, Andrew; Kuo, Byron; Yauk, Carole L; White, Paul A; Halappanavar, Sabina

    2017-07-01

    The assumption of additivity applied in the risk assessment of environmental mixtures containing carcinogenic polycyclic aromatic hydrocarbons (PAHs) was investigated using transcriptomics. MutaTMMouse were gavaged for 28 days with three doses of eight individual PAHs, two defined mixtures of PAHs, or coal tar, an environmentally ubiquitous complex mixture of PAHs. Microarrays were used to identify differentially expressed genes (DEGs) in lung tissue collected 3 days post-exposure. Cancer-related pathways perturbed by the individual or mixtures of PAHs were identified, and dose-response modeling of the DEGs was conducted to calculate gene/pathway benchmark doses (BMDs). Individual PAH-induced pathway perturbations (the median gene expression changes for all genes in a pathway relative to controls) and pathway BMDs were applied to models of additivity [i.e., concentration addition (CA), generalized concentration addition (GCA), and independent action (IA)] to generate predicted pathway-specific dose-response curves for each PAH mixture. The predicted and observed pathway dose-response curves were compared to assess the sensitivity of different additivity models. Transcriptomics-based additivity calculation showed that IA accurately predicted the pathway perturbations induced by all mixtures of PAHs. CA did not support the additivity assumption for the defined mixtures; however, GCA improved the CA predictions. Moreover, pathway BMDs derived for coal tar were comparable to BMDs derived from previously published coal tar-induced mouse lung tumor incidence data. These results suggest that in the absence of tumor incidence data, individual chemical-induced transcriptomics changes associated with cancer can be used to investigate the assumption of additivity and to predict the carcinogenic potential of a mixture.

  5. The direct influence of ship traffic on atmospheric PM2.5, PM10 and PAH in Venice.

    Science.gov (United States)

    Contini, D; Gambaro, A; Belosi, F; De Pieri, S; Cairns, W R L; Donateo, A; Zanotto, E; Citron, M

    2011-09-01

    The direct influence of ship traffic on atmospheric levels of coarse and fine particulate matter (PM(2.5), PM(10)) and fifteen polycyclic aromatic hydrocarbons (PAHs) has been estimated in the urban area of Venice. Data analysis has been performed on results collected at three sites over the summer, when ship traffic is at a maximum. Results indicate that monitoring of the PM daily concentrations is not sufficiently detailed for the evaluation of this contribution, even though it could be useful for specific markers such as PAHs. Therefore a new methodology, based on high temporal resolution measurements coupled with wind direction information and the database of ship passages of the Harbour Authority of Venice has been developed. The sampling sites were monitored with optical detectors (DustTrack(®) and Mie pDR-1200) operating at a high temporal resolution (20s and 1s respectively) for PM(2.5) and PM(10). PAH in the particulate and gas phases were recovered from quartz fibre filters and polyurethane foam plugs using pressurised solvent extraction, the extracts were then analysed by gas chromatography- high-resolution mass spectrometry. Our results shows that the direct contribution of ships traffic to PAHs in the gas phase is 10% while the contribution to PM(2.5) and to PM(10) is from 1% up to 8%. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Large-scale modeling on the fate and transport of polycyclic aromatic hydrocarbons (PAHs) in multimedia over China

    Science.gov (United States)

    Huang, Y.; Liu, M.; Wada, Y.; He, X.; Sun, X.

    2017-12-01

    In recent decades, with rapid economic growth, industrial development and urbanization, expanding pollution of polycyclic aromatic hydrocarbons (PAHs) has become a diversified and complicated phenomenon in China. However, the availability of sufficient monitoring activities for PAHs in multi-compartment and the corresponding multi-interface migration processes are still limited, especially at a large geographic area. In this study, we couple the Multimedia Fate Model (MFM) to the Community Multi-Scale Air Quality (CMAQ) model in order to consider the fugacity and the transient contamination processes. This coupled dynamic contaminant model can evaluate the detailed local variations and mass fluxes of PAHs in different environmental media (e.g., air, surface film, soil, sediment, water and vegetation) across different spatial (a county to country) and temporal (days to years) scales. This model has been applied to a large geographical domain of China at a 36 km by 36 km grid resolution. The model considers response characteristics of typical environmental medium to complex underlying surface. Results suggest that direct emission is the main input pathway of PAHs entering the atmosphere, while advection is the main outward flow of pollutants from the environment. In addition, both soil and sediment act as the main sink of PAHs and have the longest retention time. Importantly, the highest PAHs loadings are found in urbanized and densely populated regions of China, such as Yangtze River Delta and Pearl River Delta. This model can provide a good scientific basis towards a better understanding of the large-scale dynamics of environmental pollutants for land conservation and sustainable development. In a next step, the dynamic contaminant model will be integrated with the continental-scale hydrological and water resources model (i.e., Community Water Model, CWatM) to quantify a more accurate representation and feedbacks between the hydrological cycle and water quality at

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

    Science.gov (United States)

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

    2015-03-17

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

  8. Modelling Chemical Patterns of Atmospheric Polycyclic Aromatic Hydrocarbons (PAHs) in the Iberian Peninsula

    Science.gov (United States)

    Ratola, Nuno; Jiménez-Guerrero, Pedro

    2013-04-01

    Semi-volatile organic compounds (SVOCs) such as PBDEs, PCBs, organochlorine pesticides (OCPs) or PAHs, are widespread and generated in a multitude of anthropogenic (and natural for PAHs) processes and although they are found in the environment at low concentrations, possess an extraordinary carcinogenic capacity (Baussant et al., 2001) and high ecotoxicity due to their persistence in different matrices (air, soil, water, living organisms). In particular, PAHs are originated by combustion processes or release from fossil fuels and can be transported in the atmosphere over long distances in gaseous or particulate matter (Baek et al., 1991). The establishment of strategies for sampling and chemical transport modelling of SVOCs in the atmosphere aiming the definition and validation of the spatial, temporal and chemical transport patterns of contaminants can be achieved by an integrated system of third-generation models that represent the current state of knowledge in air quality modelling and experimental data collected in field campaigns. This has implications in the fields of meteorology, atmospheric chemistry and even climate change. In this case, an extensive database already obtained on levels of atmospheric PAHs from biomonitoring schemes in the Iberian Peninsula fuelled the establishment of the first models of behaviour for PAHs. The modelling system WRF+CHIMERE was implemented with high spatial and temporal resolution to the Iberian Peninsula in this first task (9 km for the Iberian Peninsula, 3 km to Portugal, 1 hour), using PAHs atmospheric levels collected over a year-long sampling scheme comprising 4 campaigns (one per season) in over 30 sites. Daily information on meteorological parameters such as air temperature, humidity, rainfall or wind speed and direction was collected from the weather stations closest to the sampling sites. Diagnosis and forecasts of these meteorological variables using MM5 or WRF were used to feed a chemistry transport model

  9. Fluorescence quenching of polycyclic aromatic hydrocarbons within deep eutectic solvents and their aqueous mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Pandey, Ashish; Yadav, Anita; Bhawna; Pandey, Siddharth, E-mail: sipandey@chemistry.iitd.ac.in

    2017-03-15

    Two common and popular deep eutectic solvents (DESs) composed of the salt choline chloride and H-bond donors glycerol and urea in 1:2 mol ratio named glyceline and reline, respectively, are investigated for the analysis of polycyclic aromatic hydrocarbons (PAHs) using quenching of both steady-state and time-resolved fluorescence of ten different PAHs by nitromethane at 30 °C. Based on their quenching efficiencies, the PAHs are divided into two groups – group 1 is constituted of the five PAHs whose fluorescence are quenched less effectively by nitromethane whereas the other five exhibiting high quenching efficiency are associated to group 2. Quenching of steady-state fluorescence of group 1 PAHs by nitromethane, albeit not very significant, follow a simple Stern-Volmer behavior. The excited-state emission intensity decay of these PAHs, in both absence and presence of nitromethane, fit best to a single exponential model with small but monotonic decrease in lifetimes. The decrease in lifetime also follows Stern-Volmer behavior, however, the quenching constants (K{sub D}) are lower than those obtained from steady-state fluorescence (K{sub SV}). This is ascribed to the possible formation of charge-transfer complex between the PAH and the nitromethane. Steady-state fluorescence quenching of group 2 PAHs exhibit distinct upward curvature from linear Stern-Volmer behavior implying highly efficient quenching. The intensity decay fits best to a double exponential decay model with longer of the decay times following simple Stern-Volmer behavior. Formation of a complex or the presence of nitromethane within the quenching sphere of action of the PAH having short decay time is proposed. Quenching behavior was found to be similar irrespective of the identity of the DES. A representative group 2 PAH, pyrene, is employed to investigate diffusion dynamics within aqueous mixtures of the two DESs. The bimolecular quenching rate constant (k{sub q}) is found to increase linearly with

  10. PAH biomarkers in common eelpout (Zoarces viviparus) from Danish waters

    DEFF Research Database (Denmark)

    Tairova, Zhanna; Strand, Jakob; Chevalier, Julie

    2012-01-01

    Eelpouts (Zoarces viviparus) sampled at surveillance stations during the fall of 2007 and spring 2008 in different Danish coastal areas, were studied for biomarkers of polycyclic aromatic hydrocarbons (PAHs) exposure and effects. Two analytical techniques, synchronous fluorescence spectrometry (SFS......) and high-performance liquid chromatography with fluorescence detection (HPLC/F), were applied for detecting PAH metabolites in bile and urine. CYP1A activity, in this study regarded as potential biomarker of effect, was measured as 7-ethoxyresorufin-O-deethylase (EROD) activity in liver of eelpouts from...... different stations. Biliary PAH metabolite measurements were used for monitoring the environmental PAH load at the surveillance stations. There was found significant difference in biliary PAH metabolite content between sexes with male fish containing higher concentrations of PAH metabolites than females...

  11. Analysis of Polycyclic Aromatic Hydrocarbons (PAHs in soils using ultrasonic agitation, heater/mini condenser tube and gaseous chromatography

    Directory of Open Access Journals (Sweden)

    Jurandir Pereira Pinto

    2006-02-01

    Full Text Available The increase in the number of gas stations in Brazil made it also possible the increase in the risk of underground waters contamination due to fuel spill. The polycyclic aromatic hydrocarbons (PAHs are petroleum-derived components and constitute a group of organic pollutants which are persistent in the environment and have highly carcinogenic capacity. In this work it was developed a PAHs analysis methodology in soils for quantifying these components, using the gaseous chromatography technique, through the optimization and validation of the chromatographic as well as the extraction, concentration and purification conditions of the PAHs. A good resolution for the sixteen PAHs was obtained, with retention times ranging from 6.1 to 43.7 minutes. The tube-heater/mini condenser system used for the solvent evaporation also showed satisfactory recovery for the naphthalene (83% as well as the extraction method by ultrasonic agitation with dichloromethane, obtaining recoveries that ranged from 74 to 104%. The analysis method proved to be appropriate for the quantification of the 16 PAHs in the evaluation of the environmental contamination in gas stations.

  12. Barns kjemiske lekemiljø: Nivå og kilder til PAH i barnehagejord i Trondheim

    OpenAIRE

    Frøland, Stine Lindset

    2008-01-01

    Innholdet av 16 PAH-forbindelser og sumPAH(16) ble bestemt i 107 prøver av overflatejord fordelt på 10 barnehager i Trondheim. Sammenlignet med tidligere undersøkelser av PAH i Trondheim viser barnehagene det laveste innholdet av PAH. I barnehagene antydes det at vedfyring og veitrafikk er viktige kilder til den diffuse forurensningen av PAH.

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

    Science.gov (United States)

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

    2014-05-01

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

  14. PAH in Some Brands of Tea and Coffee

    DEFF Research Database (Denmark)

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

    2015-01-01

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

  15. PAH related effects on fish in sedimentation ponds for road runoff and potential transfer of PAHs from sediment to biota

    DEFF Research Database (Denmark)

    Grung, Merete; Petersen, Karina; Fjeld, Eirik

    2016-01-01

    of the sedimentation ponds were high (1900-4200ngg(-1)), and even higher levels were observed in plants. Principal component analysis of selected ion chromatograms of PAHs showed a clear separation of plants vs. sediments. The plants preferentially accumulated the high molecular PAHs, both from sedimentation ponds......) the transfer of PAHs from road runoff material to aquatic organisms was substantial. Minnow from a sedimentation pond (Skullerud) near Oslo (Norway) had higher levels of CYP1A enzyme and DNA stand breaks than minnow from the nearby river, but high concentrations of PAH-metabolites in bile revealed that both...... populations were highly exposed. Principal component analysis revealed that CYP1A and age of fish were correlated, while levels of PAH-metabolites were not correlated to CYP1A or DNA damage. Minnow from a lake un-affected by traffic had much lower levels of PAH-metabolites than the exposed fish, and also...

  16. Degradation of ¹³C-labeled pyrene in soil-compost mixtures and fertilized soil.

    Science.gov (United States)

    Adam, Iris K U; Miltner, Anja; Kästner, Matthias

    2015-11-01

    Polycyclic aromatic hydrocarbons (PAH) are toxic pollutants widely distributed in the environment due to natural and anthropogenic processes. In order to mitigate tar oil contaminations with PAH, research on improving bioremediation approaches, which are sometimes inefficient, is needed. However, the knowledge on the fate of PAH-derived carbon and the microbial degraders in particular in compost-supplemented soils is still limited. Here we show the PAH carbon turnover mass balance in microcosms with soil-compost mixtures or in farmyard fertilized soil using [(13)C6]-pyrene as a model PAH. Complete pyrene degradation of 100 mg/kg of soil was observed in all supplemented microcosms within 3 to 5 months, and the residual (13)C was mainly found as carbon converted to microbial biomass. Long-term fertilization of soil with farmyard manure resulted in pyrene removal efficiency similar to compost addition, although with a much longer lag phase, higher mineralization, and lower carbon incorporation into the biomass. Organic amendments either as long-term manure fertilization or as compost amendment thus play a key role in increasing the PAH-degrading potential of the soil microbial community. Phospholipid fatty acid stable isotope probing (PLFA-SIP) was used to trace the carbon within the microbial population and the amount of biomass formed from pyrene degradation. The results demonstrate that complex microbial degrader consortia rather than the expected single key players are responsible for PAH degradation in organic-amended soil.

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

    International Nuclear Information System (INIS)

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

    2017-01-01

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

  18. Global time trends in PAH emissions from motor vehicles

    Science.gov (United States)

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

    2011-04-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-02-20

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

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

    Science.gov (United States)

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

    2015-09-01

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

  1. Development of a toxicity-based fractionation approach for the identification of phototoxic PAHs in pore water

    International Nuclear Information System (INIS)

    Kosian, P.A.; Makynen, E.A.; Ankley, G.T.; Monson, P.D.

    1995-01-01

    Environmental matrices often contain complex mixtures of chemical compounds, however, typically only a few chemicals are responsible for observed toxicity. To determine those chemicals responsible for toxicity, a toxicity-based fractionation technique coupled with gas chromatography/mass spectrometry (GC/MS) has been used for the isolation and identification of nonpolar toxicants in aqueous samples. In this study, this technique was modified to separate and identify polycyclic aromatic hydrocarbons (PAHs) responsible for phototoxicity in pore water. Whole pore water, obtained from sediments collected near an oil refinery discharge site, was found to be toxic to Lumbriculus variegatus in the presence of ultraviolet (UV) light. Solid phase extraction disks and high pressure liquid chromatography were used, in conjunction with toxicity tests with L. variegatus, to extract and fractionate phototoxic chemicals from the pore water. GC/MS analysis was performed on the toxic fractions and a tentative list of compound identifications were made based on interpretation of mass spectra and elution information from the chromatographic separation. The compounds identified include PAHs and substituted PAHs that are known or predicted to be phototoxic in the presence of UV light. The results show that a modified toxicity-based fractionation approach can be successfully applied to identify phototoxic PAHs in sediment pore water and therefore used in the assessment of contaminated sediments

  2. The evaluation of polycyclic aromatic hydrocarbons (PAHs) biodegradation kinetics in soil amended with organic fertilizers and bulking agents.

    Science.gov (United States)

    Włóka, Dariusz; Placek, Agnieszka; Rorat, Agnieszka; Smol, Marzena; Kacprzak, Małgorzata

    2017-11-01

    The aim of this study was to investigate the polycyclic aromatic hydrocarbons (PAHs) biodegradation kinetics in soils fertilized with organic amendments (sewage sludge, compost), bulking agents (mineral sorbent, silicon dioxide in form of nano powder), and novel compositions of those materials. The scope of conducted works includes a cyclic CO 2 production measurements and the determinations of PAHs content in soil samples, before and after 3-months of incubation. Obtained results show that the use of both type of organic fertilizers have a positive effect on the PAHs removal from soil. However, the CO 2 emission remains higher only in the first stage of the process. The best acquired means in terms of PAHs removal as well as most sustained CO 2 production were noted in samples treated with the mixtures of organic fertilizers and bulking agents. In conclusion the addition of structural forming materials to the organic fertilizers was critical for the soil bioremediation efficiency. Therefore, the practical implementation of collected data could find a wide range of applications during the design of new, more effective solutions for the soil bioremediation purposes. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Long-term composition dynamics of PAH-containing NAPLs and implications for risk assessment

    International Nuclear Information System (INIS)

    Peters, C.A.; Knightes, C.D.; Brown, D.G.

    1999-01-01

    Subsurface contaminants such as coal tar, creosote, diesel fuel, and other petroleum-derived materials typically exist as very complex chemical mixtures. Risk assessment is useful for site management if a single metric can represent the composition-dependent risk profile of the mixture. This paper examines the factors governing human health risk assessment for multicomponent nonaqueous phase liquids (NAPLs) containing polycyclic aromatic hydrocarbons (PAHs). A model is presented describing the interdependence of the dissolution rates of individual compounds and the shifts in the NAPL composition that occur due to the large differences in aqueous solubilities. The model also accounts for solidification of the less soluble NAPL constituents. Thirty-year numerical simulations describe composition dynamics for natural environmental processes as well as three remediation processes: pump-and-treat, bioremediation, and solvent extraction. Carcinogenic risk due to ingestion of contaminated groundwater at the source is estimated, and its dependence on contaminant removal and NAPL composition shifts is described. When composition dynamics are slow, a compound like naphthalene has great potential to contribute to risk because it may persist in groundwater. When there is significant depletion of the lower molecular weight compounds, the risk is dominated by contributions from compounds such as benzo[a]pyrene. Remediation technologies have the greatest potential for risk reduction if they are effective in removing the more carcinogenic, high molecular weight compounds. Because PAHs can contribute to risk for different reasons and because of the interdependence of their behaviors, compositional approaches lead to better risk predictions for PAHs than simple lumped metrics such as total petroleum hydrocarbon (TPH)

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

    Science.gov (United States)

    Ciemniak, Artur; Witczak, Agata

    2010-01-01

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

  5. Rapid persulfate oxidation predicts PAH bioavailability in soils and sediments

    NARCIS (Netherlands)

    Cuypers, M.P.; Grotenhuis, J.T.C.; Joziasse, J.; Rulkens, W.H.

    2000-01-01

    Persulfate oxidation was validated as a method to predict polycyclic aromatic hydrocarbon (PAH) bioavailability in soils and sediments. It was demonstrated for 14 field contaminated soils and sediments that residual PAH concentrations after a short (3 h) persulfate oxidation correspond well to

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

    African Journals Online (AJOL)

    ADOWIE PERE

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

  7. Polyaromatic hydrocarbons (PAHs) levels from two industrial zones ...

    African Journals Online (AJOL)

    Polyaromatic hydrocarbons (PAHs) levels from two industrial zones (Sihwa and Banwal) located in An-san city ... PROMOTING ACCESS TO AFRICAN RESEARCH ... method (HVAS-Sibata) was employed to collect airborne PAHs in both the particulate and gas phases. ... EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

  8. Levels of PAHs in shrimps, Penaeus monodon from Jones Creek ...

    African Journals Online (AJOL)

    High concentrations were recorded during the rainy season and during the first quarter of the year. The investigated samples were classified as minimally contaminated when compared with FDA levels of PAHs in shrimp samples. Distribution patterns showed that PAHs with 3 and 4 rings dominated confirming the pyrogenic ...

  9. Urinary 1-hydroxypyrene, a PAH biomarker in foundry workers

    DEFF Research Database (Denmark)

    Omland, Øyvind; Sherson, David; Hansen, Åse Marie

    1996-01-01

    Exposure to PAH in foundry workers has been studied by urinary 1-hydroxypyrene (HPU) levels, quantitatively measured by reversed phase HPLC. Seventy male foundry workers and 68 matched controls were investigated. Polycyclic aromatic hydrocarbon (PAH) exposure was defined by 17 breathing zone hygi...

  10. PAH loss during bioremediation of manufactured gas plant site soils

    Energy Technology Data Exchange (ETDEWEB)

    Erickson, D C [and others

    1993-01-01

    Laboratory studies using soil samples from a former gas works site showed that PAH in the soil were present in a form resistant to biodegradation, whereas added naphthalene and phenanthrene were quickly degraded. The PAH already present were not extractable into water, and were not toxic to bacteria.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-09-01

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

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

    International Nuclear Information System (INIS)

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

    2015-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Fasmi Ahmad

    2013-07-01

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

  14. Enhanced bioremediation of PAH contaminated soils from coal processing sites

    International Nuclear Information System (INIS)

    Joshi, M.M.; Lee, S.

    1995-01-01

    The polycyclic aromatic hydrocarbons (PAH) are a potential hazard to health due to their carcinogenic, mutagenic nature and acute toxicity and there is an imminent need for remediation of PAH contaminated soils abounding the several coke oven and town gas sites. Aerobic biological degradation of PAHs is an innovative technology and has shown high decontamination efficiencies, complete mineralization of contaminants, and is environmentally safe. The present study investigates the remediation of PAH contaminated soils achieved using Acinetobacter species and fungal strain Phanerochaete Chrysosporium. The soil used for the experiments was an industrially contaminated soil obtained from Alberta Research Council (ARC) primary cleanup facility, Alberta, Canada. Soil characterization was done using High Performance Liquid Chromatography (HPLC) to qualitatively and quantitatively determine the contaminants in the soil. Artificially contaminated soil was also used for some experiments. All the experiments were conducted under completely mixed conditions with suitable oxygen and nutrient amendments. The removal efficiency obtained for various PAHs using the two microorganisms was compared

  15. Electrochemical Oxidation of PAHs in Water from Harbor Sediment Purification

    DEFF Research Database (Denmark)

    Muff, Jens; Søgaard, Erik Gydesen

    2010-01-01

    generated oxidant solution with a free chlorine concentration of 2 gL-1. Both strategies resulted in a successful degradation of 5 PAHs to fulfil the discharge limit on 0.010 µgL-1. The intermixing-with-oxidant approach can also be applied as a method to address the actual sediment matrix....... of the discharge water addressing primarily polycyclic aromatic hydrocarbons (PAHs). PAHs are by-products of incomplete combustion of organic materials with recalcitrant and strong mutagenic/carcinogenic properties, due to their benzene analogue structures. PAHs are hydrophobic compounds and their persistence...... evidence for the importance of the indirect oxidation mechanism in the degradation of the PAHs. The proof-of-concept study was conducted both by a direct treatment approach and an intermixing-with-oxidant approach, where the contaminated water was intermixed in different ratios with an electrochemically...

  16. Identification and quantification of phthalates, PAHs, amines, phenols, and metals in tattoo

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Ho Sang; Lim, Hyun Hee [Kongju National University, Kongju (Korea, Republic of)

    2015-08-15

    The determination methods of polycyclic aromatic hydrocarbons (PAHs), phthalates, primary amines, phenols, and metals in tattoo dyes have been optimized and validated using gas chromatography-mass spectrometry, liquid chromatography-tandem mass spectrometry, and inductively coupled plasma-mass spectrometry. Twelve PAHs, 3 phthalates, 4 amines, and 15 metals were identified and quantified in 16 different tattoo dyes purchased from shops in the Republic of Korea. Phenols were not detected in any sample. The total PAHs in six inks and benzo(a)pyrene in one tattoo ink exceeded the legal limit set by the Council of Europe, and their maximum detected concentrations were about 10 and 5 times the limits of the compounds, respectively. 3,3′-Dichlorobenzidine and o-anisidine, which should not be present in tattoo inks by Resolution ResAP (2008) of the Council of Europe, were detected in tattoo inks. Also, Cd, Pb, Cu, Ba, Ni, Sb, Zn, and As exceeded the limits. These hazardous compounds should be controlled to the lowest possible concentrations in the raw materials and the production procedure of tattoo ink.

  17. Identification and quantification of phthalates, PAHs, amines, phenols, and metals in tattoo

    International Nuclear Information System (INIS)

    Shin, Ho Sang; Lim, Hyun Hee

    2015-01-01

    The determination methods of polycyclic aromatic hydrocarbons (PAHs), phthalates, primary amines, phenols, and metals in tattoo dyes have been optimized and validated using gas chromatography-mass spectrometry, liquid chromatography-tandem mass spectrometry, and inductively coupled plasma-mass spectrometry. Twelve PAHs, 3 phthalates, 4 amines, and 15 metals were identified and quantified in 16 different tattoo dyes purchased from shops in the Republic of Korea. Phenols were not detected in any sample. The total PAHs in six inks and benzo(a)pyrene in one tattoo ink exceeded the legal limit set by the Council of Europe, and their maximum detected concentrations were about 10 and 5 times the limits of the compounds, respectively. 3,3′-Dichlorobenzidine and o-anisidine, which should not be present in tattoo inks by Resolution ResAP (2008) of the Council of Europe, were detected in tattoo inks. Also, Cd, Pb, Cu, Ba, Ni, Sb, Zn, and As exceeded the limits. These hazardous compounds should be controlled to the lowest possible concentrations in the raw materials and the production procedure of tattoo ink

  18. Polycyclic Aromatic Hydrocarbon (PAH) and Oxygenated PAH (OPAH) Air–Water Exchange during the Deepwater Horizon Oil Spill

    Science.gov (United States)

    2015-01-01

    Passive sampling devices were used to measure air vapor and water dissolved phase concentrations of 33 polycyclic aromatic hydrocarbons (PAHs) and 22 oxygenated PAHs (OPAHs) at four Gulf of Mexico coastal sites prior to, during, and after shoreline oiling from the Deepwater Horizon oil spill (DWH). Measurements were taken at each site over a 13 month period, and flux across the water–air boundary was determined. This is the first report of vapor phase and flux of both PAHs and OPAHs during the DWH. Vapor phase sum PAH and OPAH concentrations ranged between 1 and 24 ng/m3 and 0.3 and 27 ng/m3, respectively. PAH and OPAH concentrations in air exhibited different spatial and temporal trends than in water, and air–water flux of 13 individual PAHs were strongly associated with the DWH incident. The largest PAH volatilizations occurred at the sites in Alabama and Mississippi in the summer, each nominally 10 000 ng/m2/day. Acenaphthene was the PAH with the highest observed volatilization rate of 6800 ng/m2/day in September 2010. This work represents additional evidence of the DWH incident contributing to air contamination, and provides one of the first quantitative air–water chemical flux determinations with passive sampling technology. PMID:25412353

  19. Polycyclic aromatic hydrocarbon (PAH) and oxygenated PAH (OPAH) air-water exchange during the deepwater horizon oil spill.

    Science.gov (United States)

    Tidwell, Lane G; Allan, Sarah E; O'Connell, Steven G; Hobbie, Kevin A; Smith, Brian W; Anderson, Kim A

    2015-01-06

    Passive sampling devices were used to measure air vapor and water dissolved phase concentrations of 33 polycyclic aromatic hydrocarbons (PAHs) and 22 oxygenated PAHs (OPAHs) at four Gulf of Mexico coastal sites prior to, during, and after shoreline oiling from the Deepwater Horizon oil spill (DWH). Measurements were taken at each site over a 13 month period, and flux across the water-air boundary was determined. This is the first report of vapor phase and flux of both PAHs and OPAHs during the DWH. Vapor phase sum PAH and OPAH concentrations ranged between 1 and 24 ng/m(3) and 0.3 and 27 ng/m(3), respectively. PAH and OPAH concentrations in air exhibited different spatial and temporal trends than in water, and air-water flux of 13 individual PAHs were strongly associated with the DWH incident. The largest PAH volatilizations occurred at the sites in Alabama and Mississippi in the summer, each nominally 10,000 ng/m(2)/day. Acenaphthene was the PAH with the highest observed volatilization rate of 6800 ng/m(2)/day in September 2010. This work represents additional evidence of the DWH incident contributing to air contamination, and provides one of the first quantitative air-water chemical flux determinations with passive sampling technology.

  20. Interstellar PAH in the Laboratory and in Space. What have we Learned from the New Generation of Laboratory and Observational Studies?

    Science.gov (United States)

    Salama, Farid

    2005-01-01

    Polycyclic Aromatic Hydrocarbons (PAHs) are an important and ubiquitous component of carbon-bearing materials in space. PAHs are the best-known candidates to account for the IR emission bands (UIR bands) and PAH spectral features are now being used as new probes of the ISM. PAHs are also thought to be among the carriers of the diffuse interstellar absorption bands (DIBs). In the model dealing with the interstellar spectral features, PAHs are present as a mixture of radicals, ions and neutral species. PAH ionization states reflect the ionization balance of the medium while PAH size, composition, and structure reflect the energetic and chemical history of the medium. A major challenge for laboratory astrophysics is to reproduce (in a realistic way) the physical conditions that exist in the emission and/or absorption interstellar zones. An extensive laboratory program has been developed at NASA Ames to assess the physical and chemical properties of PAHs in such environments and to describe how they influence the radiation and energy balance in space and the interstellar chemistry. In particular, laboratory experiments provide measurements of the spectral characteristics of interstellar PAH analogs from the ultraviolet and visible range to the infrared range for comparison with astronomical data. This paper will focus on the recent progress made in the laboratory to measure the direct absorption spectra of neutral and ionized PAHs in the gas phase in the near-UV and visible range in astrophysically relevant environments. These measurements provide data on PAHs and nanometer-sized particles that can now be directly compared to astronomical observations. The harsh physical conditions of the IS medium - characterized by a low temperature, an absence of collisions and strong VUV radiation fields - are simulated in the laboratory by associating a molecular beam with an ionizing discharge to generate a cold plasma expansion. PAH ions are formed from the neutral precursors in

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

    Science.gov (United States)

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

    2015-04-01

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

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

    International Nuclear Information System (INIS)

    Haritash, A.K.; Kaushik, C.P.

    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 degradation, microbial degradation is the major degradation process. PAH degradation depends on the environmental conditions, number and type of the microorganisms, nature and chemical structure of the chemical compound being degraded. They are biodegraded/biotransformed into less complex metabolites, and through mineralization into inorganic minerals, H 2 O, CO 2 (aerobic) or CH 4 (anaerobic) and rate of biodegradation depends on pH, temperature, oxygen, microbial population, degree of acclimation, accessibility of nutrients, chemical structure of the compound, cellular transport properties, and chemical partitioning in growth medium. A number of bacterial species are known to degrade PAHs and most of them are isolated from contaminated soil or sediments. Pseudomonas aeruginosa, Pseudomons fluoresens, Mycobacterium spp., Haemophilus spp., Rhodococcus spp., Paenibacillus spp. are some of the commonly studied PAH-degrading bacteria. Lignolytic fungi too have the property of PAH degradation. Phanerochaete chrysosporium, Bjerkandera adusta, and Pleurotus ostreatus are the common PAH-degrading fungi. Enzymes involved in the degradation of PAHs are oxygenase, dehydrogenase and lignolytic enzymes. Fungal lignolytic enzymes are lignin peroxidase, laccase, and manganese peroxidase. They are extracellular and catalyze radical formation by oxidation to destabilize bonds in a molecule. The biodegradation of PAHs has been observed under both aerobic and anaerobic conditions and the rate can

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

    Energy Technology Data Exchange (ETDEWEB)

    Haritash, A.K., E-mail: akharitash@gmail.com [Department of Environmental Science and Engineering, Guru Jambheshwar University of Science and Technology, Hisar, Haryana (India); Kaushik, C.P. [Department of Environmental Science and Engineering, Guru Jambheshwar University of Science and Technology, Hisar, Haryana (India)

    2009-09-30

    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 degradation, microbial degradation is the major degradation process. PAH degradation depends on the environmental conditions, number and type of the microorganisms, nature and chemical structure of the chemical compound being degraded. They are biodegraded/biotransformed into less complex metabolites, and through mineralization into inorganic minerals, H{sub 2}O, CO{sub 2} (aerobic) or CH{sub 4} (anaerobic) and rate of biodegradation depends on pH, temperature, oxygen, microbial population, degree of acclimation, accessibility of nutrients, chemical structure of the compound, cellular transport properties, and chemical partitioning in growth medium. A number of bacterial species are known to degrade PAHs and most of them are isolated from contaminated soil or sediments. Pseudomonas aeruginosa, Pseudomons fluoresens, Mycobacterium spp., Haemophilus spp., Rhodococcus spp., Paenibacillus spp. are some of the commonly studied PAH-degrading bacteria. Lignolytic fungi too have the property of PAH degradation. Phanerochaete chrysosporium, Bjerkandera adusta, and Pleurotus ostreatus are the common PAH-degrading fungi. Enzymes involved in the degradation of PAHs are oxygenase, dehydrogenase and lignolytic enzymes. Fungal lignolytic enzymes are lignin peroxidase, laccase, and manganese peroxidase. They are extracellular and catalyze radical formation by oxidation to destabilize bonds in a molecule. The biodegradation of PAHs has been observed under both aerobic and anaerobic conditions

  4. PAH related effects on fish in sedimentation ponds for road runoff and potential transfer of PAHs from sediment to biota.

    Science.gov (United States)

    Grung, Merete; Petersen, Karina; Fjeld, Eirik; Allan, Ian; Christensen, Jan H; Malmqvist, Linus M V; Meland, Sondre; Ranneklev, Sissel

    2016-10-01

    Road runoff is an important source of pollution to the aquatic environment, and sedimentation ponds have been installed to mitigate effects on the aquatic environment. The purpose of this study was to investigate if a) fish from sedimentation ponds were affected by road pollution and; b) the transfer of PAHs from road runoff material to aquatic organisms was substantial. Minnow from a sedimentation pond (Skullerud) near Oslo (Norway) had higher levels of CYP1A enzyme and DNA stand breaks than minnow from the nearby river, but high concentrations of PAH-metabolites in bile revealed that both populations were highly exposed. Principal component analysis revealed that CYP1A and age of fish were correlated, while levels of PAH-metabolites were not correlated to CYP1A or DNA damage. Minnow from a lake un-affected by traffic had much lower levels of PAH-metabolites than the exposed fish, and also an improved condition. The latter results indicate that fish health was affected by road runoff. A closer investigation of PAH levels of the ecosystems of two sedimentation ponds (Skullerud and Vassum) and nearby environments were conducted. The concentration of the 16 EPA PAHs in sediments of the sedimentation ponds were high (1900-4200ngg(-1)), and even higher levels were observed in plants. Principal component analysis of selected ion chromatograms of PAHs showed a clear separation of plants vs. sediments. The plants preferentially accumulated the high molecular PAHs, both from sedimentation ponds with a petrogenic PAH isomer ratio in sediments; and from a lake with pyrogenic PAH isomer ratio in sediments. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Amelioration of soil PAH and heavy metals by combined application of fly ash and biochar

    Science.gov (United States)

    Masto, Reginald; George, Joshy; Ansari, Md; Ram, Lal

    2016-04-01

    Generation of electricity through coal combustion produces huge quantities of fly ash. Sustainable disposal and utilization of these fly ash is a major challenge. Fly ash along with other amendments like biochar could be used for amelioration of soil. In this study, fly ash and biochar were used together for amelioration of polycyclic aromatic hydrocarbon (PAH) contaminated soil. Field experiment was conducted to investigate the effects of fly ash and biochar on the amelioration of soil PAH, and the yield of Zea mays. The treatments were control, biochar (4 t/ha), fly ash (4 t/ha), ash + biochar ( 2 + 2 t/ha). Soil samples were collected after the harvest of maize crop and analysed for chemical and biological parameters. Thirteen PAHs were analysed in the postharvest soil samples. Soil PAHs were extracted in a microwave oven at 120 °C using hexane : acetone (1:1) mixture. The extracted solutions were concentrated, cleaned and the 13 PAHs [Acenaphthene (Ace), fluorene (Flr), phenanthrene (Phn), anthracene(Ant), pyrene(Pyr), benz(a)anthracene (BaA), chrysene (Chy), benzo(b)fluoranthene (BbF), benzo(k)fluoranthene (BkF), benzo(a)pyrene, benzo(g,h,i)perylene (BghiP), dibenzo(a,h)anthracene, and indeno(1,2,3-cd)pyrene)(Inp)] were analysed using GC-MS. The mean pH increased from 6.09 in control to 6.64 and 6.58 at biochar and fly ash treated soils, respectively. N content was not affected, whereas addition of biochar alone and in combination with fly ash, has significantly increased the soil organic carbon content. P content was almost double in combined (9.06 mg/kg) treatment as compared to control (4.32 mg/kg). The increase in K due to biochar was 118%, whereas char + ash increased soil K by 64%. Soil heavy metals were decreased: Zn (-48.4%), Ni (-41.4%), Co (-36.9%), Cu (-35.7%), Mn (-34.3%), Cd (-33.2%), and Pb (-30.4%). Soil dehydrogenase activity was significantly increased by ash and biochar treatments and the maximum activity was observed for the combined

  6. The Role of Human Aldo-Keto Reductases in the Metabolic Activation and Detoxication of Polycyclic Aromatic Hydrocarbons: Interconversion of PAH Catechols and PAH o-Quinones

    Science.gov (United States)

    Zhang, Li; Jin, Yi; Huang, Meng; Penning, Trevor M.

    2012-01-01

    Polycyclic aromatic hydrocarbons (PAH) are ubiquitous environmental pollutants. They are procarcinogens requiring metabolic activation to elicit their deleterious effects. Aldo-keto reductases (AKR) catalyze the oxidation of proximate carcinogenic PAH trans-dihydrodiols to yield electrophilic and redox-active PAH o-quinones. AKRs are also found to be capable of reducing PAH o-quinones to form PAH catechols. The interconversion of o-quinones and catechols results in the redox-cycling of PAH o-quinones to give rise to the generation of reactive oxygen species and subsequent oxidative DNA damage. On the other hand, PAH catechols can be intercepted through phase II metabolism by which PAH o-quinones could be detoxified and eliminated. The aim of the present review is to summarize the role of human AKRs in the metabolic activation/detoxication of PAH and the relevance of phase II conjugation reactions to human lung carcinogenesis. PMID:23162467

  7. Improved Separation of Complex Polycyclic Aromatic Hydrocarbon Mixtures Using Novel Column Combinations in GC×GC/ToF-MS

    Science.gov (United States)

    Manzano, Carlos; Hoh, Eunha; Simonich, Staci L. Massey

    2012-01-01

    Complex mixtures of polycyclic aromatic hydrocarbons (PAHs) are difficult to resolve because of the high degree of overlap in compound vapor pressures, boiling points and mass spectral fragmentation patterns. The objective of this research was to improve the separation of complex PAH mixtures (including 97 different parent, alkyl-, nitro-, oxy-, thio-, chloro-, bromo-, and high molecular weight PAHs) using GC×GC/ToF-MS by maximizing the orthogonality of different GC column combinations and improving the separation of PAHs from the sample matrix interferences, including unresolved complex mixtures (UCM). Four different combinations of non-polar, polar, liquid crystal and nano-stationary phase columns were tested. Each column combination was optimized and evaluated for orthogonality using a method based on conditional entropy that considers the quantitative peak distribution in the entire two-dimensional space. Finally, an atmospheric particulate matter with diameter column in the first dimension and a 1.2 m × 0.10 mm × 0.10 µm NSP-35 nano-stationary phase column in the second dimension. In addition, the use of this column combination in GC×GC/ToF-MS resulted in significantly shorter analysis times (176 min) for complex PAH mixtures compared to one-dimensional GC/MS (257 min), as well as potentially reduced sample preparation time. PMID:22769970

  8. Decontamination of soils containing PAHs by electroremediation: a review.

    Science.gov (United States)

    Pazos, M; Rosales, E; Alcántara, T; Gómez, J; Sanromán, M A

    2010-05-15

    During the last years, the anthropogenic sources have contributed to organic compound penetration into the environment. One large group of persistent and toxic contaminants is the hydrophobic organic contaminants. Among them, polycyclic aromatic hydrocarbons (PAHs) have been recognized as a representative group of these pollutants with low solubility. In this paper, it is showed the electroremediation of soil contaminated with PAHs as an alternative, to organic compound removal. This technique, mainly used for heavy metal extraction, applies the electric current to promote the movement of contaminants. Nowadays the application of this technique alone or combined with other techniques as for example Fenton or bioremediation is taking fine results to PAHs removal. Although the PAHs soil decontamination by means of the electric field is in an initial stage, many researchers have demonstrated the treatment effectiveness. This paper describes the foremost principles to carry out the electroremediation of soils contaminated with PAHs, just like the different alternatives to improve the electroremediation of PAHs and also the new methodologies of PAHs removal by using hybrid technologies. Copyright (c) 2009 Elsevier B.V. All rights reserved.

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

    International Nuclear Information System (INIS)

    Tobiszewski, Marek; Namieśnik, Jacek

    2012-01-01

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

  10. PAH emissions from coal combustion and waste incineration.

    Science.gov (United States)

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

    2016-11-15

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

  11. PAH exposure through soil ingestion: Combining digestion models and bioassays

    Energy Technology Data Exchange (ETDEWEB)

    Wiele, T.R. van de; Verstraete, W. [Ghent University (BE).Laboratory Microbial Ecology and Technology (LabMET); Siciliano, S.D. [University of Saskatchewan (Canada). Department of Soil Science

    2003-07-01

    Exposure to environmental contaminants through soil ingestion is an important issue in current health risk assessment. Polycyclic aromatic hydrocarbons (PAH) or their metabolites pose risks to humans due to their toxic, mutagenic, carcinogenic or even (anti)estrogenic properties. PAH mobilization from a soil matrix (49.1{+-}1.5 mg PAH/kg DW) was assessed using a Simulator of the Human Intestinal Microbial Ecosystem (SHIME). PAH GC-MS analysis was performed on the pellet and supernatant of SHIME digests and gave 101, 92, 89 and 97% recovery for water, stomach, duodenal and colon digests, respectively. PAH release was highest for the water extract (0.51%) and the stomach digestion (0.44%). Lower mobilized fractions in the duodenum (0.13%) and colon (0.30%) digests could be attributed to PAH complexation with bile salts, dissolved organic matter or colon microbiota. The digestion model provides us with relevant information to what extent soil bound PAHs are mobilized in the gastrointestinal tract and thus reach the gut wall, prior to absorption. (orig.)

  12. Fasudil and DETA NONOate, Loaded in a Peptide-Modified Liposomal Carrier, Slow PAH Progression upon Pulmonary Delivery.

    Science.gov (United States)

    Rashid, Jahidur; Nahar, Kamrun; Raut, Snehal; Keshavarz, Ali; Ahsan, Fakhrul

    2018-05-07

    We investigated the feasibility of a combination therapy comprising fasudil, a Rho-kinase inhibitor, and DETA NONOate (diethylenetriamine NONOate, DN), a long-acting nitric oxide donor, both loaded in liposomes modified with a homing peptide, CAR (CARSKNKDC), in the treatment of pulmonary arterial hypertension (PAH). We first prepared and characterized unmodified and CAR-modified liposomes of fasudil and DN. Using individual drugs alone or a mixture of fasudil and DN as controls, we studied the efficacy of the two liposomal preparations in reducing mean pulmonary arterial pressure (mPAP) in monocrotaline (MCT) and SUGEN-hypoxia-induced PAH rats. We also conducted morphometric studies (degree of muscularization, arterial medial wall thickness, and collagen deposition) after treating the PAH rats with test and control formulations. When the rats were treated acutely and chronically, the reduction in mPAP was more pronounced in the liposomal formulation-treated rats than in plain drug-treated rats. CAR-modified liposomes were more selective in reducing mPAP than unmodified liposomes of the drugs. Both drugs, formulated in CAR-modified liposomes, reduced the degree of muscularization, medial arterial wall thickness, and collagen deposition more than the combination of plain drugs did. As seen with the in vivo data, CAR-modified liposomes of fasudil or DN increased the levels of the vasodilatory signaling molecule, cGMP, in the smooth muscle cells of PAH-afflicted human pulmonary arteries. Overall, fasudil and DN, formulated in liposomes, could be used as a combination therapy for a better management of PAH.

  13. PAH-Mineral Interactions. A Laboratory Approach to Astrophysical Catalysis

    Science.gov (United States)

    Adolfo Cruz Diaz, Gustavo; Mattioda, Andrew

    2017-06-01

    Polycyclic Aromatic Hydrocarbon (PAH) molecules carry the infrared emission features which dominate the spectra of most galactic and extragalactic sources. Our study investigates the chemical evolution, chemical properties, physical properties, thermal stability, and photostability of samples produced from the UV-irradiation of simulated mineral dust grains coated with aromatics and astrobiologically relevant ices, using infrared spectroscopy. We investigate the chemical evolution of aromatic organics via anhydrous (no H2O ice) and hydrous (H2O ice) mechanisms. The anhydrous mechanism involves UV-induced catalytic reactions between organics and dense-cloud mineral grains, whereas the hydrous mechanism incorporates H2O-rich ice mixtures with the minerals and organics. These investigations identify the chemical and physical interactions occurring between the organic species, the dust grains and water-rich ices.These laboratory simulations also generate observable IR spectroscopic parameters for future astronomical observations with infrared telescopes such as SOFIA and JWST as well as provide empirical parameters for input into astronomical models of the early stages of planetary formation. These studies give us a deeper understanding of the potential catalytic pathways mineral surfaces provide and a deeper understanding of the role of ice-organic compositions in the chemical reaction pathways and how these processes fit into the formation of new planetary systems.In order to achieve these goals we use the Harrick ‘Praying Mantis’ Diffuse Reflectance Accessory (DRIFTS), which allows FTIR measurements of dust samples under ambient conditions by measuring the light scattered by the dust sample. We have also incorporated a low -temperature reaction chamber permitting the DRIFTS measurements at low temperatures and high-vacuum. This set-up permits the analysis of the solid particles surfaces revealing the chemical species adsorbed as well as their chemical evolution

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-07-01

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

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

    Science.gov (United States)

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

    2002-05-01

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

  16. Biodegradation of PAHs by fungi in contaminated-soil containing ...

    African Journals Online (AJOL)

    PAH) benzo(a)anthracene, benzo(a) fluoranthene, benzo(a) pyrene, chrysene and phenanthrene in a soil that was sterilized and inoculated with the nonligninolytic fungi, Fusarium flocciferum and Trichoderma spp. and the ligninolytic fungi, ...

  17. Polycyclic Aromatic Hydrocarbons (PAHs) Content in Cattle Hides ...

    African Journals Online (AJOL)

    ADOWIE PERE

    ABSTRACT: Scrap rubber tyre is used as fuel for singeing animal carcasses in third world countries despite the fact that it can .... test method and the quantification of the PAH analytes using ... waste, SW-846 methods) with some modifications.

  18. PAHs sensitivity of picophytoplankton populations in the Red Sea

    KAUST Repository

    Kottuparambil, Sreejith; Agusti, Susana

    2018-01-01

    are higher than those reported for picophytoplankton from other oligotrophic marine waters and exceed by far the natural levels of PAHs in many oceans. Our findings reveal a possible adaptation of picophytoplankton populations to oil-related contaminants

  19. Enhanced PM10 bounded PAHs from shipping emissions

    Science.gov (United States)

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

    2015-05-01

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

  20. Ambient water quality criteria for polycyclic aromatic hydrocarbons (PAHs)

    Energy Technology Data Exchange (ETDEWEB)

    Nagpal, N.K.

    1993-08-13

    Ambient water quality criteria are established for polyaromatic hydrocarbons (PAH) in British Columbia. Major sources of PAH in the atmosphere and aquatic environments include, for the atmosphere, forest and prairie fires, agricultural burning, refuse burning, enclosed incineration, and heating and power, and for the aquatic environment, petroleum spillage, atmospheric deposition, wastewaters, surface land runoff, and biosynthesis. Details are presented of PAH and their characteristics, forms and transformations, occurrence in the environment, drinking water concerns, aquatic life concerns, wildlife concerns, livestock water supply concerns, and irrigation concerns. Application of criteria for aquatic life is discussed including phototoxic vs long term criteria, assessment of existing water quality, setting water quality objectives, and PAH levels in smoked fish. 221 refs., 5 figs., 30 tabs.

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

    Directory of Open Access Journals (Sweden)

    Evin Danisman Bruschweiler

    2012-10-01

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

  2. Water-Sediment Partition of Polycyclic Aromatic Hydrocarbons (PAHs) in Nansi Lake

    Science.gov (United States)

    Zhang, Guizhai; Diao, Youjiang

    2018-06-01

    Based on field data of polycyclic aromatic hydrocarbons (PAHs) in water and sediment in Nansi Lake. The concentrations and the partitioning characteristic of PAHs in the water and sediment were studied. The lgKd of high molecular weight PAHs were higher than the low molecular weight PAHs. The most of PAHs Kd values were negligible correlated with TOC, soluble salt, clay and pH of the sediment in Nansi Lake.

  3. Reductions of PAH and Soot by Center Air Injection

    Directory of Open Access Journals (Sweden)

    Kazuhiro Yamamoto

    2014-07-01

    Full Text Available In this study, to reduce the amount of pollutant PAH and soot in the flame, we examined the burner system equipped with a center air injection. For this purpose, by using PAH-LIF and soot LII, we evaluated relative PAH and soot amounts in both the triple port burner and the conventional co-axial burner (double port burner to discuss effects of center air injection on the formation of PAH and soot. The fuel was propane. In the triple port burner, two different blue flames are observed near the burner rim, followed by bright luminous flames with soot. The flame length is longer when the fuel flow velocity is increased. On the other hand, the flame length is shorter with an increase in internal air flow velocity. As for PAH and soot, these amounts of the triple port burner are much smaller than those of the double port burner. For the triple port burner, due to the center air injection, the fuel consumption occurs in both inner and outer flames. On the other hand, for the double port burner, the oxygen is supplied from one side air, and as a result, the fuel consumption rate is relatively lower. Hence, by the center air injection, the fuel consumption is largely accelerated, resulting in the reduction of PAH and soot.

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

    International Nuclear Information System (INIS)

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

    1997-01-01

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

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

    International Nuclear Information System (INIS)

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

    2005-01-01

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

  6. Enhanced Accessibility of Polycyclic Aromatic Hydrocarbons (PAHs) and Heterocyclic PAHs in Industrially Contaminated Soil after Passive Dosing of a Competitive Sorbate

    DEFF Research Database (Denmark)

    Humel, Stefan; Nørgaard Schmidt, Stine; Sumetzberger-Hasinger, Marion

    2017-01-01

    To assess the exposure to polycyclic aromatic hydrocarbons (PAHs) it is important to understand the binding mechanisms between specific soil constituents and the organic pollutant. In this study, sorptive bioaccessibility extraction (SBE) was applied to quantify the accessible PAH fraction...... in industrially contaminated soil with and without passive dosing of a competitive sorbate. SBE experiments revealed an accessible PAH fraction of 41 ± 1% (∑16 US EPA PAHs + 5 further PAHs). The passive dosing of toluene below its saturation level revealed competitive binding and resulted in an average increase.......4% PAH. We explain increased PAH desorption after addition of toluene by competitive adsorption to high-affinity sorption sites while acknowledging that toluene could additionally have increased PAH mobility within the soil matrix. Findings suggest that the presence of copollutants at contaminated sites...

  7. Bioremediation of PAH contaminated soil samples

    International Nuclear Information System (INIS)

    Joshi, M.M.; Lee, S.

    1994-01-01

    Soils contaminated with polynuclear aromatic hydrocarbons (PAHs) pose a hazard to life. The remediation of such sites can be done using physical, chemical, and biological treatment methods or a combination of them. It is of interest to study the decontamination of soil using bioremediation. The experiments were conducted using Acinetobacter (ATCC 31012) at room temperature without pH or temperature control. In the first series of experiments, contaminated soil samples obtained from Alberta Research Council were analyzed to determine the toxic contaminant and their composition in the soil. These samples were then treated using aerobic fermentation and removal efficiency for each contaminant was determined. In the second series of experiments, a single contaminant was used to prepare a synthetic soil sample. This sample of known composition was then treated using aerobic fermentation in continuously stirred flasks. In one set of flasks, contaminant was the only carbon source and in the other set, starch was an additional carbon source. In the third series of experiments, the synthetic contaminated soil sample was treated in continuously stirred flasks in the first set and in fixed bed in the second set and the removal efficiencies were compared. The removal efficiencies obtained indicated the extent of biodegradation for various contaminants, the effect of additional carbon source, and performance in fixed bed without external aeration

  8. Evaluation of the efficiency of continuous wavelet transform as processing and preprocessing algorithm for resolution of overlapped signals in univariate and multivariate regression analyses; an application to ternary and quaternary mixtures

    Science.gov (United States)

    Hegazy, Maha A.; Lotfy, Hayam M.; Mowaka, Shereen; Mohamed, Ekram Hany

    2016-07-01

    Wavelets have been adapted for a vast number of signal-processing applications due to the amount of information that can be extracted from a signal. In this work, a comparative study on the efficiency of continuous wavelet transform (CWT) as a signal processing tool in univariate regression and a pre-processing tool in multivariate analysis using partial least square (CWT-PLS) was conducted. These were applied to complex spectral signals of ternary and quaternary mixtures. CWT-PLS method succeeded in the simultaneous determination of a quaternary mixture of drotaverine (DRO), caffeine (CAF), paracetamol (PAR) and p-aminophenol (PAP, the major impurity of paracetamol). While, the univariate CWT failed to simultaneously determine the quaternary mixture components and was able to determine only PAR and PAP, the ternary mixtures of DRO, CAF, and PAR and CAF, PAR, and PAP. During the calculations of CWT, different wavelet families were tested. The univariate CWT method was validated according to the ICH guidelines. While for the development of the CWT-PLS model a calibration set was prepared by means of an orthogonal experimental design and their absorption spectra were recorded and processed by CWT. The CWT-PLS model was constructed by regression between the wavelet coefficients and concentration matrices and validation was performed by both cross validation and external validation sets. Both methods were successfully applied for determination of the studied drugs in pharmaceutical formulations.

  9. Phototransformation rate constants of PAHs associated with soot particles

    International Nuclear Information System (INIS)

    Kim, Daekyun; Young, Thomas M.; Anastasio, Cort

    2013-01-01

    Photodegradation is a key process governing the residence time and fate of polycyclic aromatic hydrocarbons (PAHs) in particles, both in the atmosphere and after deposition. We have measured photodegradation rate constants of PAHs in bulk deposits of soot particles illuminated with simulated sunlight. The photodegradation rate constants at the surface (k p 0 ), the effective diffusion coefficients (D eff ), and the light penetration depths (z 0.5 ) for PAHs on soot layers of variable thickness were determined by fitting experimental data with a model of coupled photolysis and diffusion. The overall disappearance rates of irradiated low molecular weight PAHs (with 2–3 rings) on soot particles were influenced by fast photodegradation and fast diffusion kinetics, while those of high molecular weight PAHs (with 4 or more rings) were apparently controlled by either the combination of slow photodegradation and slow diffusion kinetics or by very slow diffusion kinetics alone. The value of z 0.5 is more sensitive to the soot layer thickness than the k p 0 value. As the thickness of the soot layer increases, the z 0.5 values increase, but the k p 0 values are almost constant. The effective diffusion coefficients calculated from dark experiments are generally higher than those from the model fitting method for illumination experiments. Due to the correlation between k p 0 and z 0.5 in thinner layers, D eff should be estimated by an independent method for better accuracy. Despite some limitations of the model used in this study, the fitted parameters were useful for describing empirical results of photodegradation of soot-associated PAHs. - Highlights: ► PAHs on soot were evaluated by a model of coupled photolysis and diffusion. ► Photodegradation rate at the surface, diffusion coefficient, and light penetration path were determined. ► Low MW PAHs were influenced by fast photodegradation and fast diffusion. ► High MW PAHs were controlled either by slow

  10. Optimal mixture experiments

    CERN Document Server

    Sinha, B K; Pal, Manisha; Das, P

    2014-01-01

    The book dwells mainly on the optimality aspects of mixture designs. As mixture models are a special case of regression models, a general discussion on regression designs has been presented, which includes topics like continuous designs, de la Garza phenomenon, Loewner order domination, Equivalence theorems for different optimality criteria and standard optimality results for single variable polynomial regression and multivariate linear and quadratic regression models. This is followed by a review of the available literature on estimation of parameters in mixture models. Based on recent research findings, the volume also introduces optimal mixture designs for estimation of optimum mixing proportions in different mixture models, which include Scheffé’s quadratic model, Darroch-Waller model, log- contrast model, mixture-amount models, random coefficient models and multi-response model.  Robust mixture designs and mixture designs in blocks have been also reviewed. Moreover, some applications of mixture desig...

  11. Petroleum hydrocarbons and polycyclic aromatic hydrocarbons (PAHs) in Hong Kong marine sediments

    International Nuclear Information System (INIS)

    Zheng, G.J.; Richardson, B.J.

    1999-01-01

    A total of 20 surficial sediment samples, obtained from Hong Kong coastal waters, were analysed for petroleum hydrocarbons (PHCs) and a suite of 15 polycyclic aromatic hydrocarbons (PAHs). The results indicate that Hong Kong coastal sediments are often seriously polluted with petroleum related hydrocarbons. This is especially so in heavily urbanised or industrialized localities, such as Kowloon Bay (Victoria Harbour), Tsing Yi North and Tolo Harbour. Petroleum hydrocarbon pollutants in marine sediments are believed to be mainly derived from the transportation of oil, shipping activities, spillages, and industrial, stormwater and waste wastewater discharge. The ratio of unresolved complex mixture (UCM) to n-alkanes, carbon preference index (CPI), and n-C 16 values indicate that the main contribution to petroleum hydrocarbon contamination is via oil and its products. Pollutant sources appear to be stable and continuing when compared with previous data. (author)

  12. Content of PAHs, activities of γ-radionuclides and ecotoxicological assessment in biochars

    Directory of Open Access Journals (Sweden)

    Gondek Krzysztof

    2016-12-01

    Full Text Available The aim of this research was to determine the effect of thermal conversion temperature and plant material addition to sewage sludge on the PAHs content and the activity of selected γ-radionuclides in biochars, and to conduct an ecotoxicological assessment. The pyrolysis of the mixtures of sewage sludge and plant materials at 300°C and such temperature caused an increase in the contents of 2- and 3-ring hydrocarbons. During the pyrolysis of organic materials at 600°C, the amount of the following compounds was reduced in biochars: benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, indeno[1,2,3c,d]pyrene, dibenzo[a,h]anthracene, and benzo[g,h,i]perylene. Among γ-radioisotopes of the elements, natural radiogenic isotopes were dominant. 137Cs was the only artificial radioactive isotope. The pyrolysis of the mixtures of municipal sewage sludge and plant materials revealed that isotope 40K had the highest radioactive activity. In the case of other analysed nuclides, activities of 212Pb, 214Pb, 214Bi, and 137Cs were determined after the sample pyrolysis. The extracts from the mixtures of sewage sludge and plant materials were non-toxic to Vibrio fischeri.

  13. A metabolomics strategy to assess the combined toxicity of polycyclic aromatic hydrocarbons (PAHs) and short-chain chlorinated paraffins (SCCPs).

    Science.gov (United States)

    Wang, Feidi; Zhang, Haijun; Geng, Ningbo; Ren, Xiaoqian; Zhang, Baoqin; Gong, Yufeng; Chen, Jiping

    2018-03-01

    The combined toxicity of mixed chemicals is usually evaluated according to several specific endpoints, and other potentially toxic effects are disregarded. In this study, we provided a metabolomics strategy to achieve a comprehensive understanding of toxicological interactions between mixed chemicals on metabolism. The metabolic changes were quantified by a pseudotargeted analysis, and the types of combined effects were quantitatively discriminated according to the calculation of metabolic effect level index (MELI). The metabolomics strategy was used to assess the combined effects of polycyclic aromatic hydrocarbons (PAHs) and short-chain chlorinated paraffins (SCCPs) on the metabolism of human hepatoma HepG2 cells. Our data suggested that exposure to a combination of PAHs and SCCPs at human internal exposure levels could result in an additive effect on the overall metabolism, whereas diverse joint effects were observed on various metabolic pathways. The combined exposure could induce a synergistic up-regulation of phospholipid metabolism, an additive up-regulation of fatty acid metabolism, an additive down-regulation of tricarboxylic acid cycle and glycolysis, and an antagonistic effect on purine metabolism. SCCPs in the mixture acted as the primary driver for the acceleration of phospholipid and fatty acid metabolism. Lipid metabolism disorder caused by exposure to a combination of PAHs and SCCPs should be an important concern for human health. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Observational Evidence Linking Interstellar UV Absorption to PAH Molecules

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-02-20

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

  15. Observational Evidence Linking Interstellar UV Absorption to PAH Molecules

    International Nuclear Information System (INIS)

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

    2017-01-01

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

  16. Monitoring of polycyclic aromatic hydrocarbons (PAH) in food supplements containing botanicals and other ingredients on the Dutch market

    NARCIS (Netherlands)

    Martena, M.J.; Grutters, M.; Groot, de H.N.; Konings, E.J.M.; Rietjens, I.

    2011-01-01

    Food supplements can contain polycyclic aromatic hydrocarbons (PAH). The European Food Safety Authority (EFSA) has defined 16 priority PAH that are both genotoxic and carcinogenic and identified eight priority PAH (PAH8) or four of these (PAH4) as good indicators of the toxicity and occurrence of

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

    DEFF Research Database (Denmark)

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

    2006-01-01

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

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

    Science.gov (United States)

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

    2016-11-01

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

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

    DEFF Research Database (Denmark)

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

    2006-01-01

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

  20. High-resolution record of pyrogenic polycyclic aromatic hydrocarbon deposition during the 20th century.

    Science.gov (United States)

    Lima, Ana Lúcia C; Eglinton, Timothy I; Reddy, Christopher M

    2003-01-01

    A high-resolution record of polycyclic aromatic hydrocarbon (PAH) deposition in Rhode Island over the past approximately 180 years was constructed using a sediment core from the anoxic Pettaquamscutt River basin. The record showed significantly more structure than has hitherto been reported and revealed four distinct maxima in PAH flux. The characteristic increase in PAH flux at the turn of the 20th century was captured in detail, leading to an initial maximum prior to the Great Depression. The overall peak in PAH flux in the 1950s was followed by a maximum that immediately preceded the 1973 Organization of Petroleum Exporting Countries (OPEC) oil embargo. During the most recent portion of the record, an abrupt increase in PAH flux between 1996 and 1999 has been found to follow a period of near constant fluxes. Because source-diagnostic ratios indicate that petrogenic inputs are minor throughout the record, these trends are interpreted in terms of past variations in the magnitude and type of combustion processes. For the most recent PAH maximum, energy consumption data suggest that diesel fuel combustion, and hence traffic of heavier vehicles, is the most probable cause for the increase in PAH flux. Systematic variations in the relative abundance of individual PAHs in conjunction with the above changes in flux are interpreted in relation to the evolution of combustion processes. Coronene, retene, and perylene are notable exceptions, exhibiting unique down-core profiles.

  1. Model-based experimental design for assessing effects of mixtures of chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Baas, Jan, E-mail: jan.baas@falw.vu.n [Vrije Universiteit of Amsterdam, Dept of Theoretical Biology, De Boelelaan 1085, 1081 HV Amsterdam (Netherlands); Stefanowicz, Anna M., E-mail: anna.stefanowicz@uj.edu.p [Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387 Krakow (Poland); Klimek, Beata, E-mail: beata.klimek@uj.edu.p [Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387 Krakow (Poland); Laskowski, Ryszard, E-mail: ryszard.laskowski@uj.edu.p [Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387 Krakow (Poland); Kooijman, Sebastiaan A.L.M., E-mail: bas@bio.vu.n [Vrije Universiteit of Amsterdam, Dept of Theoretical Biology, De Boelelaan 1085, 1081 HV Amsterdam (Netherlands)

    2010-01-15

    We exposed flour beetles (Tribolium castaneum) to a mixture of four poly aromatic hydrocarbons (PAHs). The experimental setup was chosen such that the emphasis was on assessing partial effects. We interpreted the effects of the mixture by a process-based model, with a threshold concentration for effects on survival. The behavior of the threshold concentration was one of the key features of this research. We showed that the threshold concentration is shared by toxicants with the same mode of action, which gives a mechanistic explanation for the observation that toxic effects in mixtures may occur in concentration ranges where the individual components do not show effects. Our approach gives reliable predictions of partial effects on survival and allows for a reduction of experimental effort in assessing effects of mixtures, extrapolations to other mixtures, other points in time, or in a wider perspective to other organisms. - We show a mechanistic approach to assess effects of mixtures in low concentrations.

  2. Model-based experimental design for assessing effects of mixtures of chemicals

    International Nuclear Information System (INIS)

    Baas, Jan; Stefanowicz, Anna M.; Klimek, Beata; Laskowski, Ryszard; Kooijman, Sebastiaan A.L.M.

    2010-01-01

    We exposed flour beetles (Tribolium castaneum) to a mixture of four poly aromatic hydrocarbons (PAHs). The experimental setup was chosen such that the emphasis was on assessing partial effects. We interpreted the effects of the mixture by a process-based model, with a threshold concentration for effects on survival. The behavior of the threshold concentration was one of the key features of this research. We showed that the threshold concentration is shared by toxicants with the same mode of action, which gives a mechanistic explanation for the observation that toxic effects in mixtures may occur in concentration ranges where the individual components do not show effects. Our approach gives reliable predictions of partial effects on survival and allows for a reduction of experimental effort in assessing effects of mixtures, extrapolations to other mixtures, other points in time, or in a wider perspective to other organisms. - We show a mechanistic approach to assess effects of mixtures in low concentrations.

  3. PAHs sensitivity of picophytoplankton populations in the Red Sea.

    Science.gov (United States)

    Kottuparambil, Sreejith; Agusti, Susana

    2018-04-25

    In this study, we investigated the in situ responses of Red Sea picophytoplankton, the dominant phytoplankton group in the oligotrophic ocean, to two toxic polycyclic aromatic hydrocarbons (PAHs), phenanthrene and pyrene. The experiments were conducted across a latitudinal gradient of the Saudi Arabian Red Sea, an area sensitive to oil pollution. We observed significant adverse effects on the growth and abundance of the picocyanobacteria Synechococcus and picoeukaryotes, at all stations sampled. Prochlorococcus, which was abundant only at one of the stations, also appeared to be affected. Pyrene was found to be more toxic to phytoplankton at all stations. In general, picoeukaryotes exhibited higher sensitivity to PAHs than Synechococcus. Populations in the highly oligotrophic Northern region of the Red Sea were more tolerant to PAHs, presumably influenced by the natural selection of more resistant strains of phytoplankton due to the prolonged exposure to PAHs. Toxicity threshold values estimated here are higher than those reported for picophytoplankton from other oligotrophic marine waters and exceed by far the natural levels of PAHs in many oceans. Our findings reveal a possible adaptation of picophytoplankton populations to oil-related contaminants, which may clearly influence their spatial distribution patterns in the Red Sea. Copyright © 2018 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

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

    2014-08-01

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

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

    International Nuclear Information System (INIS)

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

    1999-01-01

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

  6. PAHs sensitivity of picophytoplankton populations in the Red Sea

    KAUST Repository

    Kottuparambil, Sreejith

    2018-04-25

    In this study, we investigated the in situ responses of Red Sea picophytoplankton, the dominant phytoplankton group in the oligotrophic ocean, to two toxic polycyclic aromatic hydrocarbons (PAHs), phenanthrene and pyrene. The experiments were conducted across a latitudinal gradient of the Saudi Arabian Red Sea, an area sensitive to oil pollution. We observed significant adverse effects on the growth and abundance of the picocyanobacteria Synechococcus and picoeukaryotes, at all stations sampled. Prochlorococcus, which was abundant only at one of the stations, also appeared to be affected. Pyrene was found to be more toxic to phytoplankton at all stations. In general, picoeukaryotes exhibited higher sensitivity to PAHs than Synechococcus. Populations in the highly oligotrophic Northern region of the Red Sea were more tolerant to PAHs, presumably influenced by the natural selection of more resistant strains of phytoplankton due to the prolonged exposure to PAHs. Toxicity threshold values estimated here are higher than those reported for picophytoplankton from other oligotrophic marine waters and exceed by far the natural levels of PAHs in many oceans. Our findings reveal a possible adaptation of picophytoplankton populations to oil-related contaminants, which may clearly influence their spatial distribution patterns in the Red Sea.

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

    International Nuclear Information System (INIS)

    Wang, Ruwei; Liu, Guijian; Zhang, Jiamei

    2015-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-12-15

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

  9. Juvenile Male Rats Exposed to a Low-Dose Mixture of Twenty-Seven Environmental Chemicals Display Adverse Health Effects

    DEFF Research Database (Denmark)

    Hadrup, Niels; Svingen, Terje; Egebjerg, Karen Mandrup

    2016-01-01

    of 27 chemicals administered orally to juvenile male rats for three months could leave a pathophysiological footprint. The mixture contained metals, perfluorinated compounds, PCB, dioxins, pesticides, heterocyclic amines, phthalate, PAHs and others, with a combined dose of 0.16 (Low dose), 0.47 (Mid...

  10. Bioassay-based risk assessment of complex mixtures

    International Nuclear Information System (INIS)

    Donnelly, K.C.; Huebner, H.J.

    1996-01-01

    The baseline risk assessment often plays an integral role in various decision-making processes at Superfund sites. The present study reports on risk characterizations prepared for seven complex mixtures using biological and chemical analysis. Three of the samples (A, B, and C) were complex mixtures of polycyclic aromatic hydrocarbons (PAHs) extracted from coal tar; while four samples extracted from munitions-contaminated soil contained primarily nitroaromatic hydrocarbons. The chemical-based risk assessment ranked sample C as least toxic, while the risk associated with samples A and B was approximately equal. The microbial bioassay was in general agreement for the coal tar samples. The weighted activity of the coal tar extracts in Salmonella was 4,960 for sample C, and 162,000 and 206,000 for samples A and B, respectively. The bacterial mutagenicity of 2,4,6-trinitrotoluene contaminated soils exhibited an indirect correlation with chemical-based risk assessment. The aqueous extract of sample 004 induced 1,292 net revertants in Salmonella, while the estimated risk to ingestion and dermal adsorption was 2E-9. The data indicate that the chemical-based risk assessment accurately predicted the genotoxicity of the PAHs, while the accuracy of the risk assessment for munitions contaminated soils was limited due to the presence of metabolites of TNT degradation. The biological tests used in this research provide a valuable compliment to chemical analysis for characterizing the genotoxic risk of complex mixtures

  11. PAHs in corn grains submitted to drying with firewood.

    Science.gov (United States)

    de Lima, Rafael Friedrich; Dionello, Rafael Gomes; Peralba, Maria do Carmo Ruaro; Barrionuevo, Simone; Radunz, Lauri Lourenço; Reichert Júnior, Francisco Wilson

    2017-01-15

    Grain drying using firewood as fuel for air heating, with direct fire, is still widely used in Brazil. The combustion of organic material, such as wood, can generate polycyclic aromatic hydrocarbons (PAHs) which are known to have carcinogenic potential. In the present work corn grain drying was carried out at three drying air temperatures: 60°C, 60/80°C and 80°C. Following the drying process, the presence and quantification of PAH in the corn grains was investigated. After extracting the PAHs of the matrix, the material was subjected to analysis by gas chromatography with mass detector. he results showed the presence of seven compounds: fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)anthracene and chrysene. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Intestinal metabolism of PAH: in vitro demonstration and study of its impact on PAH transfer through the intestinal epithelium

    International Nuclear Information System (INIS)

    Cavret, Severine; Feidt, Cyril

    2005-01-01

    Food would seem to be one of the main ways of animal and human contamination with polycyclic aromatic hydrocarbons (PAHs). In vivo studies suggest a transfer in intestinal epithelium by diffusion, which appears extensively governed by the physicochemical properties of PAHs, particularly lipophilicity. However, other mechanisms, such as metabolism, are considered to intervene. Our work aimed at testing in vitro intestinal metabolism and defining its impact on transepithelial transport of PAHs. Caco-2 cells were cultivated on permeable filters and incubated with 14 C-labeled benzo[a]pyrene (BaP), pyrene (Pyr), and phenanthrene (Phe), which differ in their physicochemical properties. The results showed that the cells were able to metabolize the compounds. In basal media, Phe appeared to be the least hydroxylated molecule (45% after a 6-h exposure), followed by Pyr (65%) and finally BaP (96%). Inhibition of PAH metabolism showed a determinant effect on kinetics profiles. Transfer in the basal compartment of BaP, Pyr, and Phe radioactivities was, respectively, 26, 4, and 2 times lower with inhibitors, corroborating that intestinal metabolism of PAHs would have a positive impact on their transfer, an impact that increased with their lipophilicity. Furthermore, after a 6-h incubation, metabolites were also detected in apical medium. These findings suggested that intestinal metabolism might play a key role in intestinal barrier permeability and thus in the bioavailability of tested micropollutants

  13. Liquids and liquid mixtures

    CERN Document Server

    Rowlinson, J S; Baldwin, J E; Buckingham, A D; Danishefsky, S

    2013-01-01

    Liquids and Liquid Mixtures, Third Edition explores the equilibrium properties of liquids and liquid mixtures and relates them to the properties of the constituent molecules using the methods of statistical thermodynamics. Topics covered include the critical state, fluid mixtures at high pressures, and the statistical thermodynamics of fluids and mixtures. This book consists of eight chapters and begins with an overview of the liquid state and the thermodynamic properties of liquids and liquid mixtures, including vapor pressure and heat capacities. The discussion then turns to the thermodynami

  14. Tranport of p-aminohippuric acid (3H-PAH), inulin and dextran out of the cranial cavity: A methodological study using intraventricular injection and sample combustion

    International Nuclear Information System (INIS)

    Jakobson, Aa. M.

    1987-01-01

    Material injected into the cerebral ventricles can leave the cerebrospinal fluid (CSF) but remain in the cranial cavity. To analyze the disappearance of 3 H- and of 14 C-labelled material from the cranial cavity, such material was injected into the lateral ventricles together with a bulk flow marker, labelled with the other radionuclide. In the present pilot study 3 H-PAH and 14 C-inulin were used. Five μl of a mixture was injected into each lateral cerebral ventricles in rats, which were killed at various intervals. The whole skull was analyzed without opening the CSF space after homogenization in the deep-frozen state. The samples were combusted and analyzed by liquid scintillation counting. Probenecid, injected intraperitoneally, inhibited the removal of 3 H-PAH from the skull cavity, as anticipated. Immediately after the intraventricular injection, however, 3 H-PAH was transiently retained, probably by uptake into actively transporting tissue. After injection of probenecid, this delay in removal was reduced. The difference in disappearance rate between 3 H-PAH and 14 C-inulin was estimated by comparing the 3 H/ 14 C ratio in the skulls with that in the injected solution, which appeared to be a better method than comparing the recovery of each compound. (author)

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

    Science.gov (United States)

    Ofomatah, Anthony C; Okoye, Chukwuma O B

    2017-11-09

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

  16. Evaluation of bio-remediation technologies for PAHs contaminated soils

    International Nuclear Information System (INIS)

    Garcia Frutos, F.J.; Diaz, J.; Rodriguez, V.; Escolano, O.; Garcia, S.; Perez, R.; Martinez, R.; Oromendia, R.

    2005-01-01

    Natural attenuation is a new concept related to polluted soil remediation. Can be understood like an 'in situ' bio-remediation process with low technical intervention. This low intervention may be in order to follow the behaviour of pollutants 'monitored natural attenuation' or include an optimisation process to improve biological remediation. The use of this technology is a fact for light hydrocarbon polluted soil, but few is known about the behaviour of polycyclic aromatic hydrocarbons (PAHs) in this process. PAHs are more recalcitrant to bio-remediation due to their physic-chemical characteristics, mainly hydrophobicity and electrochemical stability. PAHs are a kind of pollutants widely distributed in the environment, not only in the proximity of the source. This linked to the characteristics of some of them related to toxicity and mutagenicity implies its inclusion as target compounds from an environmental point of view. Their low availability, solubility and the strong tendency to bind to soil particle, especially to the organic phase affect PAHs biological mineralisation. So, if the pollutant is not available to microorganisms it can not be bio-degraded. Bioavailability can be assessed form several but complementary points of view: physico-chemical and biological. First including the term availability and the second to point out the capacity of soil microorganisms to mineralize PAHs. Availability and Bio-degradability must be determined, as well as the presence and activity of specific degraders among the soil organisms, once settled these points is necessary to study the biological requirements to optimise biodegradation kinetics of these compounds. In this work we present a study carried out on a soil, contaminated by PAHs, the study includes three main topics: bioavailability assessment (both term availability and bio-degradability), bio-remediation assessment, once optimised conditions for natural attenuation and finally a simulation of the

  17. A Resolved and Asymmetric Ring of PAHs within the Young Circumstellar Disk of IRS 48

    Energy Technology Data Exchange (ETDEWEB)

    Schworer, Guillaume; Lacour, Sylvestre; Du Foresto, Vincent Coudé [LESIA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universits, UPMC Univ. Paris 06, Univ. Paris Diderot, Sorbonne Paris Cité (France); Huélamo, Nuria [Dpto. Astrofísica, Centro de Astrobiología (INTA-CSIC), ESAC Campus, P.O. Box 78, E-28691, Villanueva de la Cañada (Spain); Pinte, Christophe; Chauvin, Gaël [Univ. Grenoble Alpes, IPAG, F-38000 Grenoble, France CNRS, IPAG, F-38000 Grenoble (France); Ehrenreich, David [Observatoire de l’Université de Genève, 51 chemin des Maillettes, 1290 Versoix (Switzerland); Girard, Julien [European Southern Observatory, Alonso de Cordova 3107, Casilla 19001 Vitacura, Santiago 19 (Chile); Tuthill, Peter [Sydney Institute for Astronomy, School of Physics, The University of Sydney, NSW 2006 (Australia)

    2017-06-20

    For one decade, the spectral type and age of the ρ Oph object IRS-48 were subject to debate and mystery. Modeling its disk with mid-infrared to millimeter observations led to various explanations to account for the complex intricacy of dust holes and gas-depleted regions. We present multi-epoch high-angular-resolution interferometric near-infrared data of spatially resolved emissions in the first 15 au of IRS-48, known to have very strong polycyclic aromatic hydrocarbon (PAH) emissions within this dust-depleted region. We make use of new Sparse-Aperture-Masking data to instruct a revised radiative-transfer model, where spectral energy distribution fluxes and interferometry are jointly fitted. Neutral and ionized PAH, very small grains (VSG), and classical silicates are incorporated into the model; new stellar parameters and extinction laws are explored. A bright (42 L {sub ⊙}) and hence large (2.5 R {sub ⊙}) central star with A {sub v} = 12.5 mag and R {sub v} = 6.5 requires less near-infrared excess: the inner-most disk at ≈1 au is incompatible with the interferometric data. The revised stellar parameters place this system on a 4 Myr evolutionary track, four times younger than the previous estimations, which is in better agreement with the surrounding ρ Oph region and disk-lifetime observations. The disk-structure solution converges to a classical-grain outer disk from 55 au combined with an unsettled and fully resolved VSG and PAH ring, between 11 and 26 au. We find two overluminosities in the PAH ring at color-temperatures consistent with the radiative transfer simulations; one follows a Keplerian circular orbit at 14 au. We show a depletion of a factor of ≈5 of classical dust grains up to 0.3 mm compared to very small particles: the IRS-48 disk is nearly void of dust grains in the first 55 au. A 3.5 M {sub Jup} planet on a 40 au orbit can qualitatively explain the new disk structure.

  18. Strong Impact on the Polycyclic Aromatic Hydrocarbon (PAH)-Degrading Community of a PAH-Polluted Soil but Marginal Effect on PAH Degradation when Priming with Bioremediated Soil Dominated by Mycobacteria

    DEFF Research Database (Denmark)

    Johnsen, Anders R.; Schmidt, Stine; Hybholdt, Trine K.

    2007-01-01

    Bioaugmentation of soil polluted with polycyclic aromatic hydrocarbons (PAHs) is often disappointing because of the low survival rate and low activity of the introduced degrader bacteria. We therefore investigated the possibility of priming PAH degradation in soil by adding 2% of bioremediated soil...... with a high capacity for PAH degradation. The culturable PAH-degrading community of the bioremediated primer soil was dominated by Mycobacterium spp. A microcosm containing pristine soil artificially polluted with PAHs and primed with bioremediated soil showed a fast, 100- to 1,000-fold increase in numbers...... of culturable phenanthrene-, pyrene-, and fluoranthene degraders and a 160-fold increase in copy numbers of the mycobacterial PAH dioxygenase gene pdo1. A nonpolluted microcosm primed with bioremediated soil showed a high rate of survival of the introduced degrader community during the 112 days of incubation...

  19. Coal-tar pavement sealants might substantially increase children's PAH exposures

    Science.gov (United States)

    Williams, E. Spencer; Mahler, Barbara J.; Van Metre, Peter C.

    2012-01-01

    Dietary ingestion has been identified repeatedly as the primary route of human exposure to polycyclic aromatic hydrocarbons (PAHs), seven of which are classified as probable human carcinogens (B2 PAHs) by the U.S. EPA. Humans are exposed to PAHs through ingestion of cooked and uncooked foods, incidental ingestion of soil and dust, inhalation of ambient air, and absorption through skin. Although PAH sources are ubiquitous in the environment, one recently identified PAH source stands out: Coal-tar-based pavement sealant—a product applied to many parking lots, driveways, and even playgrounds primarily in the central, southern, and eastern U.S.—has PAH concentrations 100–1000 times greater than most other PAH sources. It was reported recently that PAH concentrations in house dust in residences adjacent to parking lots with coal-tar-based sealant were 25 times higher than in residences adjacent to unsealed asphalt parking lots.

  20. PAH growth initiated by propargyl addition: Mechanism development and computational kinetics

    KAUST Repository

    Raj, Abhijeet Dhayal; Rachidi, Mariam El; Chung, Suk-Ho; Sarathy, Mani

    2014-01-01

    Polycyclic aromatic hydrocarbon (PAH) growth is known to be the principal pathway to soot formation during fuel combustion, as such, a physical understanding of the PAH growth mechanism is needed to effectively assess, predict, and control soot

  1. Biological risk and pollution history of polycyclic aromatic hydrocarbons (PAHs) in Nansha mangrove, South China.

    Science.gov (United States)

    Wu, Qihang; Leung, Jonathan Y S; Tam, Nora F Y; Chen, Shejun; Mai, Bixian; Zhou, Xizhen; Xia, Lihua; Geng, Xinhua

    2014-08-15

    Chinese government has taken various measures to alleviate pollution caused by polycyclic aromatic hydrocarbons (PAHs) in the region of Pearl River Delta since the economic reform in 1978, but the effectiveness of these measures remains largely unknown. This study aimed to elucidate the biological risk and pollution history of PAHs by measuring the concentrations of 28 PAHs in the surface and core sediments, respectively, in Nansha mangrove. Results found that the biological risk of PAHs was low without obvious spatial variation. The PAH concentration along the depth gradient indicated that PAH pollution was stabilized since the early 1990s while the source of PAHs has gradually changed from combustion of coal to petroleum products. This implied that the mitigation measures taken by the Chinese government were effective. Compared to marine bottom sediment, we propose that using mangrove sediment can provide a more accurate and precise estimate of pollution history of PAHs. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Structural dynamics of PAH molecules upon energetic photon or ion interactions

    NARCIS (Netherlands)

    Reitsma, Geert

    2014-01-01

    Polycyclische aromatische koolwaterstoffen (PAHs) vormen een hele bijzondere familie van moleculen. PAHs bestaan uit ringen van koolstofatomen en hebben waterstofatomen op de randen. Zo ontstaan platte en heel erg stabiele moleculen. Deze moleculen komen overal voor, bijvoorbeeld in uitlaatgassen en

  3. Multispecies and monoculture rhizoremediation of polycyclic aromatic hydrocarbons (PAHs) from the soil

    CSIR Research Space (South Africa)

    Maila, MP

    2005-01-01

    Full Text Available In this study, the authors investigated the potential of multispecies rhizoremediation and monoculture rhizoremediation in decontaminating polycyclic aromatic hydrocarbon (PAH) contaminated soil. Plant-mediated PAH dissipation was evaluated using...

  4. Impact of soil amendments and the plant rhizosphere on PAH behaviour in soil

    DEFF Research Database (Denmark)

    Marchal, Geoffrey; Smith, Kilian E.C.; Mayer, Philipp

    2014-01-01

    Carbonaceous amendments reduce PAH dissolved concentrations (Cfree), limiting their uptake and toxicity. A soil contaminated with PAHs was mixed with activated carbon (AC), charcoal or compost and planted with radish (Raphanus sativus L.), and Cfree, chemical activities and diffusive uptake...

  5. Splicing of phenylalanine hydroxylase (PAH) exon 11 is vulnerable - Molecular pathology of mutations in PAH exon 11

    DEFF Research Database (Denmark)

    Heintz, Caroline; Dobrowolski, Steven F.; Andersen, Henriette Skovgaard

    2012-01-01

    as a vulnerable exon and used patient derived lymphoblast cell lines and PAH minigenes to study the molecular defect that impacted pre-mRNA processing. We showed that the c.1144T>C and c.1066-3C>T mutations cause exon 11 skipping, while the c.1139C>T mutation is neutral or slightly beneficial. The c.1144T......In about 20-30% of phenylketonuria (PKU) patients, phenylalanine (Phe) levels can be controlled by cofactor 6R-tetrahydrobiopterin (BH(4)) administration. The phenylalanine hydroxylase (PAH) genotype has a predictive value concerning BH(4)-response and therefore a correct assessment of the mutation...... molecular pathology is important. Mutations that disturb the splicing of exons (e.g. interplay between splice site strength and regulatory sequences like exon splicing enhancers (ESEs)/exon splicing silencers (ESSs)) may cause different severity of PKU. In this study, we identified PAH exon 11...

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

    Science.gov (United States)

    Wang, Ruwei; Liu, Guijian; Zhang, Jiamei

    2015-12-15

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

  7. Association of common variants in PAH and LAT1 with non-syndromic cleft lip with or without cleft palate (NSCL/P) in the Polish population.

    Science.gov (United States)

    Hozyasz, Kamil K; Mostowska, Adrianna; Wójcicki, Piotr; Lasota, Agnieszka; Wołkowicz, Anna; Dunin-Wilczyńska, Izabella; Jagodziński, Paweł P

    2014-04-01

    Non-syndromic cleft lip with or without cleft palate (NSCL/P) is a common structural malformation with a complex and multifactorial aetiology. Associations of abnormalities in phenylalanine metabolism and orofacial clefts have been suggested. Eight single nucleotide polymorphisms (SNPs) of genes encoding phenylalanine hydroxylase (PAH) and large neutral l-amino acid transporter type 1 (LAT1), as well as the PAH mutation that is most common in the Polish population (rs5030858; R408W), were investigated in 263 patients with NSCL/P and 270 matched controls using high resolution melting curve analysis (HRM). We found that two polymorphic variants of PAH appear to be risk factors for NSCL/P. The odds ratio (OR) for individuals with the rs7485331 A allele (AC or AA) compared to CC homozygotes was 0.616 (95% confidence interval [CI]=0.437-0.868; p=0.005) and this association remains statistically significant after multiple testing correction. The PAH rs12425434, previously associated with schizophrenia, was borderline associated with orofacial clefts. Moreover, haplotype analysis of polymorphisms in the PAH gene revealed a 4-marker combination that was significantly associated with NSCL/P. The global p-value for a haplotype comprised of SNPs rs74385331, rs12425434, rs1722392, and the mutation rs5030858 was 0.032, but this association did not survive multiple testing correction. This study suggests the involvement of the PAH gene in the aetiology of NSCL/P in the tested population. Further replication will be required in separate cohorts to confirm the consistency of the observed association. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. 气相色谱氩、氪、氙、氡分离度初步研究%Resolutions on Mixture of Argon, Krypton, Xenon and Radon by Gas Chromatography

    Institute of Scientific and Technical Information of China (English)

    刘蜀疆; 陈占营; 常印忠; 王世联; 李奇; 石建芳; 樊元庆; 赵允刚

    2012-01-01

    核爆炸产生多种稀有气体核素,这些核素可作为核泄露监测对象.气相色谱是组分分离的重要手段,在核爆炸监测取样中有重要应用.本文以5A分子筛作为固定相,高纯氮作为流动相,测量了氩、氪、氙、氡在气相色谱中的分离效果.结果表明,在相同色谱条件下,氩、氪分离度小于氪、氙分离度;在柱流量35.6 mL/min、柱温353 K条件下,气相色谱氩、氪,氪、氙,氙、氡分离度均大于2.25.%Radio-isotopes of noble gas, which are produced during nuclear explosion, can escape into atmosphere easily. These isotopes can be measured as good indicators for nuclear explosion. Noble gas monitoring, including sampling, measurement and analysis, became more and more essential. Gas chromatography is an important technology on noble gas separation during gas sampling. In this paper, while 5A molecular sieve was utilized as column stationary state and high-purity nitrogen as column fluid state, resolutions of argon, krypton, xenon and radon were widely investigated under different chromatograph conditions. As a result, the resolution of krypton and argon is less than the resolution of xenon and krypton; when column flow rate is 35. 6 mL/min and oven temperature is 353 K, all of the resolutions of radon and xenon, xenon and krypton, krypton and argon are more than 2. 25.

  9. PAH in Barbecued Meat from Restaurants and by Home-Grilling in Denmark

    DEFF Research Database (Denmark)

    Duedahl-Olesen, Lene; Meinert, L.; Aaslyng, M.

    2011-01-01

    Barbecuing or grilling is known to result in the formation of polycyclic aromatic hydrocarbons (PAH). Thirty home-grilled meat samples (beef, pork and chicken) and 86 commercial grilled meat samples (beef, pork, chicken, salmon, lamb and calf) were analyzed for 23 PAH including PAH 4 (benzo[a]pyr...

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

    International Nuclear Information System (INIS)

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

    2006-01-01

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

  11. Enrichment behavior and transport mechanism of soil-bound PAHs during rainfall-runoff events

    International Nuclear Information System (INIS)

    Zheng Yi; Luo Xiaolin; Zhang Wei; Wu Bin; Han Feng; Lin Zhongrong; Wang Xuejun

    2012-01-01

    Polycyclic Aromatic Hydrocarbons (PAHs) transported by surface runoff result in nonpoint source pollution and jeopardize aquatic ecosystems. The transport mechanism of PAHs during rainfall-runoff events has been rarely studied regarding pervious areas. An experimental system was setup to simulate the runoff pollution process on PAHs-contaminated soil. The enrichment behavior of soil-bound PAHs was investigated. The results show that soil organic matters (SOM), rather than clay particles, seem to be the main carrier of PAHs. The enrichment is highly conditioned on runoff and erosion processes, and its magnitude varies among PAH compounds. It is not feasible to build a simple and universal relationship between enrichment ratio and sediment discharge following the traditional enrichment theory. To estimate the flux of PAHs from pervious areas, soil erosion process has to be clearly understood, and both organic carbon content and composition of SOM should be factored into the calculation. - Highlights: ► Significant enrichment of particle-bound PAHs during rainfall-runoff events. ► Organic matters as the direct carrier of PAHs in runoff from contaminated soil. ► The traditional enrichment theory is not fully valid for PAHs. - The traditional enrichment theory is not fully valid for PAHs, and soil organic matters have a significant impact on the transport of PAHs during rainfall-runoff events.

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

    International Nuclear Information System (INIS)

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

    2015-01-01

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

  13. Comparative effects of several cyclodextrins on the extraction of PAHs from an aged contaminated soil

    International Nuclear Information System (INIS)

    Sánchez-Trujillo, M.A.; Morillo, E.; Villaverde, J.; Lacorte, S.

    2013-01-01

    The objective of the present study was to characterise the polycyclic aromatic hydrocarbons (PAHs) content of an aged contaminated soil and to propose remediation techniques using cyclodextrins (CDs). Four CDs solutions were tested as soil decontamination tool and proved more efficient in extracting PAHs than when an aqueous solution was used; especially two chemically modified CDs resulted in higher extraction percentages than natural β-CD. The highest extraction percentages were obtained for 3-ring PAHs, because of the appropriate size and shape of these compounds relative to those of the hydrophobic cavities of the CDs studied. A detailed mechanistic interpretation of the chemical modification of CDs on the extraction of the different PAHs has been performed, and connected with the role that the different hydrophobicities of the PAHs play in the extraction behaviour observed for the 16 PAHs, limiting their accessibility and the remaining risk of those PAHs not extractable by CDs. -- Highlights: ► Four cyclodextrins (CDs) solutions were tested as soil decontamination tool for PAHs. ► Extractions with CDs were higher than with electrolyte, especially with synthetic CDs. ► Extraction capacity depends on the adequate size of PAHs and CDs hydrophobic cavity. ► 2–3 ring PAHs, the more abundant in the soil, were extracted in higher percentages. ► CDs extract preferably the less hydrophobic and more potentially toxic PAHs. -- Cyclodextrin solutions are useful and interesting tools for the decontamination of soils polluted by PAHs

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-02-15

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

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

    Science.gov (United States)

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

    2017-12-01

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

  16. Urinary concentrations of PAH and VOC metabolites in marijuana users.

    Science.gov (United States)

    Wei, Binnian; Alwis, K Udeni; Li, Zheng; Wang, Lanqing; Valentin-Blasini, Liza; Sosnoff, Connie S; Xia, Yang; Conway, Kevin P; Blount, Benjamin C

    2016-03-01

    Marijuana is seeing increased therapeutic use, and is the world's third most-popular recreational drug following alcohol and tobacco. This widening use poses increased exposure to potentially toxic combustion by-products from marijuana smoke and the potential for public health concerns. To compare urinary metabolites of polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs) among self-reported recent marijuana users and nonusers, while accounting for tobacco smoke exposure. Measurements of PAH and VOC metabolites in urine samples were combined with questionnaire data collected from participants in the National Health and Nutrition Examination Surveys (NHANES) from 2005 to 2012 in order to categorize participants (≥18years) into exclusive recent marijuana users and nonusers. Adjusted geometric means (GMs) of urinary concentrations were computed for these groups using multiple regression analyses to adjust for potential confounders. Adjusted GMs of many individual monohydroxy PAHs (OH-PAHs) were significantly higher in recent marijuana users than in nonusers (pmarijuana users than in nonusers. We found elevated levels of biomarkers for potentially harmful chemicals among self-identified, recent marijuana users compared with nonusers. These findings suggest that further studies are needed to evaluate the potential health risks to humans from the exposure to these agents when smoking marijuana. Published by Elsevier Ltd.

  17. Investigating the temporal trends in PAH, PCB and OCP ...

    African Journals Online (AJOL)

    2013-05-09

    May 9, 2013 ... mation on application of passive sampling in South Africa is available in the literature. This study was ..... molecular weight PAHs in the current study were on average up to 2 orders of magnitude lower ..... VAN REI WF (1987) The Hartbeespoort dam – a magnet to millions? In: Thornton JA and Walmsley RD ...

  18. Bioremediation of polyaromatic hydrocarbons (PAHs using rhizosphere technology

    Directory of Open Access Journals (Sweden)

    Sandeep Bisht

    2015-03-01

    Full Text Available The remediation of polluted sites has become a priority for society because of increase in quality of life standards and the awareness of environmental issues. Over the past few decades there has been avid interest in developing in situ strategies for remediation of environmental contaminants, because of the high economic cost of physicochemical strategies, the biological tools for remediation of these persistent pollutants is the better option. Major foci have been considered on persistent organic chemicals i.e.polyaromatic hydrocarbons (PAHs due to their ubiquitous occurrence, recalcitrance, bioaccumulation potential and carcinogenic activity. Rhizoremediation, a specific type of phytoremediation that involves both plants and their associated rhizospheric microbes is the creative biotechnological approach that has been explored in this review. Moreover, in this review we showed the significance of rhizoremediation of PAHs from other bioremediation strategies i.e. natural attenuation, bioaugmentation and phytoremediation and also analyze certain environmental factor that may influence the rhizoremediation technique. Numerous bacterial species were reported to degrade variety of PAHs and most of them are isolated from contaminated soil, however few reports are available from non contaminated soil. Pseudomonas aeruginosa, Pseudomons fluoresens, Mycobacterium spp., Haemophilus spp., Rhodococcus spp., Paenibacillus spp. are some of the commonly studied PAH-degrading bacteria. Finally, exploring the molecular communication between plants and microbes, and exploiting this communication to achieve better results in the elimination of contaminants, is a fascinating area of research for future perspective.

  19. Cosmic PAHs: from infrared astronomy to laboratory astrophysics

    Science.gov (United States)

    Joblin, Christine

    2017-06-01

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

  20. MULTIMEDIA CONCENTRATIONS OF PAH IN SEVERAL DAY CARE CENTERS

    Science.gov (United States)

    Concentrations of polycyclic aromatic hydrocarbons were measured in nine day care centers in the spring of 1997. Indoor and outdoor air, food and beverages, indoor dust, and outdoor play area soil were sampled. The mean sums of 20 target PAH concentrations were 265 and 199 ng...

  1. Small phosphatidate phosphatase (TtPAH2) of Tetrahymena ...

    Indian Academy of Sciences (India)

    Anoop Narayana Pillai

    2017-10-03

    Oct 3, 2017 ... There was no significant difference (indicated as 'ns') in the number of lipid droplets as analysed by Kruskal-Wallis test. (p \\0.01). .... and Goodman JM 2011 The yeast lipin orthologue Pah1p is ... gamma transcriptional activity.

  2. Polycyclic aromatic hydrocarbons (PAH) in Danish barbecued meat

    DEFF Research Database (Denmark)

    Duedahl-Olesen, Lene; Aaslyng, Margit Dall; Meinert, Lene

    2015-01-01

    Barbecuing is known to result in the formation of polycyclic aromatic hydrocarbons (PAHs). A validated method that employed pressurized liquid extraction (PLE), gel permeation chromatography (GPC) followed by solid phase extraction (SPE) on Silica and analytical determination by GC-MS was applied...

  3. PAH desorption from river floodplain soils using supercritical fluid extraction

    Czech Academy of Sciences Publication Activity Database

    Yang, Y.; Cajthaml, Tomáš; Hofmann, T.

    2008-01-01

    Roč. 156, č. 3 (2008), s. 745-752 ISSN 0269-7491 R&D Projects: GA MŠk 2B06156 Institutional research plan: CEZ:AV0Z50200510 Keywords : pahs * slow desorption * carbonaceous materials Subject RIV: EE - Microbiology, Virology Impact factor: 3.135, year: 2008

  4. Bioremediation of polyaromatic hydrocarbons (PAHs) using rhizosphere technology

    Science.gov (United States)

    Bisht, Sandeep; Pandey, Piyush; Bhargava, Bhavya; Sharma, Shivesh; Kumar, Vivek; Sharma, Krishan D.

    2015-01-01

    The remediation of polluted sites has become a priority for society because of increase in quality of life standards and the awareness of environmental issues. Over the past few decades there has been avid interest in developing in situ strategies for remediation of environmental contaminants, because of the high economic cost of physicochemical strategies, the biological tools for remediation of these persistent pollutants is the better option. Major foci have been considered on persistent organic chemicals i.e. polyaromatic hydrocarbons (PAHs) due to their ubiquitous occurrence, recalcitrance, bioaccumulation potential and carcinogenic activity. Rhizoremediation, a specific type of phytoremediation that involves both plants and their associated rhizospheric microbes is the creative biotechnological approach that has been explored in this review. Moreover, in this review we showed the significance of rhizoremediation of PAHs from other bioremediation strategies i.e. natural attenuation, bioaugmentation and phytoremediation and also analyze certain environmental factor that may influence the rhizoremediation technique. Numerous bacterial species were reported to degrade variety of PAHs and most of them are isolated from contaminated soil, however few reports are available from non contaminated soil. Pseudomonas aeruginosa , Pseudomons fluoresens , Mycobacterium spp., Haemophilus spp., Rhodococcus spp., Paenibacillus spp. are some of the commonly studied PAH-degrading bacteria. Finally, exploring the molecular communication between plants and microbes, and exploiting this communication to achieve better results in the elimination of contaminants, is a fascinating area of research for future perspective. PMID:26221084

  5. Improving bioremediation of PAH contaminated soils by thermal pretreatment

    NARCIS (Netherlands)

    Bonten, L.

    2001-01-01

    Numerous sites and large volumes of sediments in the Netherlands are contaminated with polycyclic aromatic hydrocarbons (PAH), which are of great concern because of their

  6. Effect of smoking on Polycyclic Aromatic Hydrocarbons (PAHS ...

    African Journals Online (AJOL)

    The effects of smoking on proximate composition, energy values and concentrations of polycyclic aromatic hydrocarbons (PAHs) were studied in raw and smoked samples of catfish (Clarias gariepinus) and tilapia (Oreochromis niloticus). Crude protein was higher in the tilapia sample for both raw and smoked samples.

  7. PAHs, OCPs and PCBs in sediments from three catchments in ...

    African Journals Online (AJOL)

    Based on the comparison of chemical concentrations to international sediment quality guidelines, PAH, OCP and PCB concentrations in most sediment samples posed a low risk to sediment-dwelling organisms. However, in some instances the risk was moderate or high. It is recommended that these compounds be ...

  8. PAHs molecules and heating of the interstellar gas

    Science.gov (United States)

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

    1989-01-01

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

  9. Analytical Evaluation to Determine Selected PAHs in a Contaminated Soil With Type II Fuel

    International Nuclear Information System (INIS)

    Garcia Alonso, S.; Perez Pastor, R. M.; Sevillano Castano, M. L.; Garcia Frutos, F. J.

    2010-01-01

    A study on the optimization of an ultrasonic extraction method for selected PAHs determination in soil contaminated by type II fuel and by using HPLC with fluorescence detector is presented. The main objective was optimize the analytical procedure, minimizing the volume of solvent and analysis time and avoiding possible loss by evaporation. This work was carried out as part of a project that investigated a remediation process of agricultural land affected by an accidental spillage of fuel (Plan Nacional I + D + i, CTM2007-64 537). The paper is structured as: Optimization of wavelengths in the chromatographic conditions to improve resolution in the analysis of fuel samples. Optimization of the main parameters affecting in the extraction process by sonication. Comparison of results with those obtained by accelerated solvent extraction. (Author) 3 refs.

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

    International Nuclear Information System (INIS)

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

    1992-01-01

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

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

    Science.gov (United States)

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

    2011-10-01

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

  12. PHOTOCHEMISTRY OF POLYCYCLIC AROMATIC HYDROCARBONS IN COSMIC WATER ICE: THE ROLE OF PAH IONIZATION AND CONCENTRATION

    International Nuclear Information System (INIS)

    Cook, Amanda M.; Mattioda, Andrew L.; Roser, Joseph; Bregman, Jonathan; Ricca, Alessandra; Allamandola, Louis J.; Bouwman, Jordy; Linnartz, Harold

    2015-01-01

    Infrared spectroscopic studies of ultraviolet (UV) irradiated, water-rich, cosmic ice analogs containing small polycyclic aromatic hydrocarbons (PAHs) are described. The irradiation studies of anthracene:H 2 O, pyrene:H 2 O, and benzo[ghi]perylene:H 2 O ices (14 K) at various concentrations reported by Bouwman et al. are extended. While aromatic alcohols and ketones have been reported in residues after irradiated PAH:H 2 O ices were warmed to 270 K, it was not known if they formed during ice irradiation or during warm-up when reactants interact as H 2 O sublimes. Recent work has shown that they form in low temperature ice. Using DFT computed IR spectra to identify photoproducts and PAH cations, we tentatively identify the production of specific alcohols [PAH(OH) n ] and quinones [PAH(O) n ] for all PAH:H 2 O ices considered here. Little evidence is found for hydrogenation at 14 K, consistent with the findings of Gudipati and Yang. Addition of O and OH to the parent PAH is the dominant photochemical reaction, but PAH erosion to smaller PAHs (producing CO 2 and H 2 CO) is also important. DFT spectra are used to assess the contribution of PAH-related species to interstellar absorption features from 5 to 9 μm. The case is made that PAH cations are important contributors to the C2 component and PAH(OH) n and PAH(O) n to the C5 component described by Boogert et al. Thus, interstellar ices should contain neutral and ionized PAHs, alcohols, ketones and quinones at the ∼2%-4% level relative to H 2 O. PAHs, their photoproducts, and ion-mediated processes should therefore be considered when modeling interstellar ice processes

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

    International Nuclear Information System (INIS)

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

    2014-01-01

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

  14. PHOTOCHEMISTRY OF POLYCYCLIC AROMATIC HYDROCARBONS IN COSMIC WATER ICE: THE ROLE OF PAH IONIZATION AND CONCENTRATION

    Energy Technology Data Exchange (ETDEWEB)

    Cook, Amanda M.; Mattioda, Andrew L.; Roser, Joseph; Bregman, Jonathan [NASA Ames Research Center, PO Box 1, M/S 245-6, Moffett Field, CA 94035 (United States); Ricca, Alessandra; Allamandola, Louis J. [SETI Institute, 189 North Bernardo Avenue, Mountain View, CA 94043 (United States); Bouwman, Jordy [Radboud University Nijmegen, Institute for Molecules and Materials, Toernooiveld 5, 6525 ED Nijmegen (Netherlands); Linnartz, Harold [Sackler Laboratory for Astrophysics, Leiden Observatory, University of Leiden, PO Box 9513, NL2300 RA Leiden (Netherlands)

    2015-01-20

    Infrared spectroscopic studies of ultraviolet (UV) irradiated, water-rich, cosmic ice analogs containing small polycyclic aromatic hydrocarbons (PAHs) are described. The irradiation studies of anthracene:H{sub 2}O, pyrene:H{sub 2}O, and benzo[ghi]perylene:H{sub 2}O ices (14 K) at various concentrations reported by Bouwman et al. are extended. While aromatic alcohols and ketones have been reported in residues after irradiated PAH:H{sub 2}O ices were warmed to 270 K, it was not known if they formed during ice irradiation or during warm-up when reactants interact as H{sub 2}O sublimes. Recent work has shown that they form in low temperature ice. Using DFT computed IR spectra to identify photoproducts and PAH cations, we tentatively identify the production of specific alcohols [PAH(OH) {sub n} ] and quinones [PAH(O) {sub n} ] for all PAH:H{sub 2}O ices considered here. Little evidence is found for hydrogenation at 14 K, consistent with the findings of Gudipati and Yang. Addition of O and OH to the parent PAH is the dominant photochemical reaction, but PAH erosion to smaller PAHs (producing CO{sub 2} and H{sub 2}CO) is also important. DFT spectra are used to assess the contribution of PAH-related species to interstellar absorption features from 5 to 9 μm. The case is made that PAH cations are important contributors to the C2 component and PAH(OH) {sub n} and PAH(O) {sub n} to the C5 component described by Boogert et al. Thus, interstellar ices should contain neutral and ionized PAHs, alcohols, ketones and quinones at the ∼2%-4% level relative to H{sub 2}O. PAHs, their photoproducts, and ion-mediated processes should therefore be considered when modeling interstellar ice processes.

  15. Polycyclic aromatic hydrocarbons as skin carcinogens: Comparison of benzo[a]pyrene, dibenzo[def,p]chrysene and three environmental mixtures in the FVB/N mouse

    International Nuclear Information System (INIS)

    Siddens, Lisbeth K.; Larkin, Andrew; Krueger, Sharon K.; Bradfield, Christopher A.; Waters, Katrina M.; Tilton, Susan C.; Pereira, Cliff B.; Löhr, Christiane V.; Arlt, Volker M.; Phillips, David H.; Williams, David E.

    2012-01-01

    The polycyclic aromatic hydrocarbon (PAH), benzo[a]pyrene (BaP), was compared to dibenzo[def,p]chrysene (DBC) and combinations of three environmental PAH mixtures (coal tar, diesel particulate and cigarette smoke condensate) using a two stage, FVB/N mouse skin tumor model. DBC (4 nmol) was most potent, reaching 100% tumor incidence with a shorter latency to tumor formation, less than 20 weeks of 12-O-tetradecanoylphorbol-13-acetate (TPA) promotion compared to all other treatments. Multiplicity was 4 times greater than BaP (400 nmol). Both PAHs produced primarily papillomas followed by squamous cell carcinoma and carcinoma in situ. Diesel particulate extract (1 mg SRM 1650b; mix 1) did not differ from toluene controls and failed to elicit a carcinogenic response. Addition of coal tar extract (1 mg SRM 1597a; mix 2) produced a response similar to BaP. Further addition of 2 mg of cigarette smoke condensate (mix 3) did not alter the response with mix 2. PAH-DNA adducts measured in epidermis 12 h post initiation and analyzed by 32 P post‐labeling, did not correlate with tumor incidence. PAH‐dependent alteration in transcriptome of skin 12 h post initiation was assessed by microarray. Principal component analysis (sum of all treatments) of the 922 significantly altered genes (p < 0.05), showed DBC and BaP to cluster distinct from PAH mixtures and each other. BaP and mixtures up-regulated phase 1 and phase 2 metabolizing enzymes while DBC did not. The carcinogenicity with DBC and two of the mixtures was much greater than would be predicted based on published Relative Potency Factors (RPFs). -- Highlights: ► Dibenzo[def,p]chrysene (DBC), 3 PAH mixtures, benzo[a]pyrene (BaP) were compared. ► DBC and 2 PAH mixtures were more potent than Relative Potency Factor estimates. ► Transcriptome profiles 12 hours post initiation were analyzed by microarray. ► Principle components analysis of alterations revealed treatment-based clustering. ► DBC gave a unique pattern of

  16. Polycyclic aromatic hydrocarbons as skin carcinogens: Comparison of benzo[a]pyrene, dibenzo[def,p]chrysene and three environmental mixtures in the FVB/N mouse

    Energy Technology Data Exchange (ETDEWEB)

    Siddens, Lisbeth K.; Larkin, Andrew [Department of Environmental and Molecular Toxicology, Oregon State University (United States); Superfund Research Center, Oregon State University (United States); Krueger, Sharon K. [Superfund Research Center, Oregon State University (United States); The Linus Pauling Institute, Oregon State University (United States); Bradfield, Christopher A. [McArdle Laboratory for Cancer Research, University of Wisconsin, Madison, WI 53706 (United States); Waters, Katrina M.; Tilton, Susan C. [Superfund Research Center, Oregon State University (United States); Computational Biology and Bioinformatics Group, Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Pereira, Cliff B. [Superfund Research Center, Oregon State University (United States); Deptartment of Statistics, Oregon State University, Corvallis, OR 97331 (United States); Environmental Health Sciences Center, Oregon State University, Corvallis, OR 97331 (United States); Löhr, Christiane V. [Environmental Health Sciences Center, Oregon State University, Corvallis, OR 97331 (United States); College of Veterinary Medicine, Oregon State University, Corvallis, OR 97331 (United States); Arlt, Volker M.; Phillips, David H. [Analytical and Environmental Sciences Division, MRC-HPA Centre for Environment and Health, King' s College London, London SE1 9NH (United Kingdom); Williams, David E., E-mail: david.williams@oregonstate.edu [Department of Environmental and Molecular Toxicology, Oregon State University (United States); Superfund Research Center, Oregon State University (United States); The Linus Pauling Institute, Oregon State University (United States); Environmental Health Sciences Center, Oregon State University, Corvallis, OR 97331 (United States); and others

    2012-11-01

    The polycyclic aromatic hydrocarbon (PAH), benzo[a]pyrene (BaP), was compared to dibenzo[def,p]chrysene (DBC) and combinations of three environmental PAH mixtures (coal tar, diesel particulate and cigarette smoke condensate) using a two stage, FVB/N mouse skin tumor model. DBC (4 nmol) was most potent, reaching 100% tumor incidence with a shorter latency to tumor formation, less than 20 weeks of 12-O-tetradecanoylphorbol-13-acetate (TPA) promotion compared to all other treatments. Multiplicity was 4 times greater than BaP (400 nmol). Both PAHs produced primarily papillomas followed by squamous cell carcinoma and carcinoma in situ. Diesel particulate extract (1 mg SRM 1650b; mix 1) did not differ from toluene controls and failed to elicit a carcinogenic response. Addition of coal tar extract (1 mg SRM 1597a; mix 2) produced a response similar to BaP. Further addition of 2 mg of cigarette smoke condensate (mix 3) did not alter the response with mix 2. PAH-DNA adducts measured in epidermis 12 h post initiation and analyzed by {sup 32}P post‐labeling, did not correlate with tumor incidence. PAH‐dependent alteration in transcriptome of skin 12 h post initiation was assessed by microarray. Principal component analysis (sum of all treatments) of the 922 significantly altered genes (p < 0.05), showed DBC and BaP to cluster distinct from PAH mixtures and each other. BaP and mixtures up-regulated phase 1 and phase 2 metabolizing enzymes while DBC did not. The carcinogenicity with DBC and two of the mixtures was much greater than would be predicted based on published Relative Potency Factors (RPFs). -- Highlights: ► Dibenzo[def,p]chrysene (DBC), 3 PAH mixtures, benzo[a]pyrene (BaP) were compared. ► DBC and 2 PAH mixtures were more potent than Relative Potency Factor estimates. ► Transcriptome profiles 12 hours post initiation were analyzed by microarray. ► Principle components analysis of alterations revealed treatment-based clustering. ► DBC gave a unique

  17. Identification and determination of the contribution of iron-steel manufacturing industry to sediment-associated polycyclic aromatic hydrocarbons (PAHs) in a large shallow lake of eastern China.

    Science.gov (United States)

    Zhang, Liu; Bai, Ya-Shu; Wang, Ji-Zhong; Peng, Shu-Chuan; Chen, Tian-Hu; Yin, Da-Qiang

    2016-11-01

    Seventeen polycyclic aromatic hydrocarbon (PAH) compounds were determined in surface sediments collected from the Chaohu Lake (a large shallow lake in eastern China) and its tributaries. Both diagnostic ratios and a receptor model (positive matrix factorization, PMF) were applied to identify and determine the contribution of a local iron-steel manufacturing plant located in the Nanfei River (NFR) to the Chaohu Lake basin. The results show that sites located in the downstream of the steel plant contained concentrations of 17 PAH (Σ 17 PAH) approximately two orders of magnitudes higher than those from other sites. Five factors were identified by the PMF model, including industrial waste, wood/biomass burning, diagenetic origin, domestic coal combustion, and industrial combustion. Our findings suggest that sediments in the downstream of the plant and in the western part of the Chaohu Lake were predominantly affected by industrial coal combustion. A mixture of pyrolytic origins impacted urban sediments in the upstream of the plant, whereas diagenetic origins along with coal and biomass burning were suggested to influence the eastern part and rural tributaries of the lake. To assess the potential ecological risk and toxicity caused by the iron-steel plant, sediment toxicity was evaluated by the PMF model, sediment quality guideline, and toxic equivalent factors. All of the three approaches suggested PAH accumulation in the NFR sediments could produce significant adverse ecological effects and half of the sediment toxicity in the NFR may be attributed to the emissions from the iron-steel plant. Some rural locations also exhibited PAH concentrations above probable effects, most likely contributed by wood/biomass burning.

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

    Science.gov (United States)

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

    2011-12-01

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

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

    Directory of Open Access Journals (Sweden)

    L. Poulain

    2011-12-01

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

  20. Exposure to polycyclic aromatic hydrocarbons (PAHs) and bladder cancer: evaluation from a gene-environment perspective in a hospital-based case-control study in the Canary Islands (Spain)

    Science.gov (United States)

    Boada, Luis D; Henríquez-Hernández, Luis A; Navarro, Patricio; Zumbado, Manuel; Almeida-González, Maira; Camacho, María; Álvarez-León, Eva E; Valencia-Santana, Jorge A; Luzardo, Octavio P

    2015-01-01

    Background: Exposure to polycyclic aromatic hydrocarbons (PAHs) has been linked to bladder cancer. Objective: To evaluate the role of PAHs in bladder cancer, PAHs serum levels were measured in patients and controls from a case-control study. Methods: A total of 140 bladder cancer patients and 206 healthy controls were included in the study. Sixteen PAHs were analyzed from the serum of subjects by gas chromatography–mass spectrometry. Results: Serum PAHs did not appear to be related to bladder cancer risk, although the profile of contamination by PAHs was different between patients and controls: pyrene (Pyr) was solely detected in controls and chrysene (Chry) was exclusively detected in the cases. Phenanthrene (Phe) serum levels were inversely associated with bladder cancer (OR = 0·79, 95%CI = 0·64–0·99, P = 0·030), although this effect disappeared when the allelic distribution of glutathione-S-transferase polymorphisms of the population was introduced into the model (multinomial logistic regression test, P = 0·933). Smoking (OR = 3·62, 95%CI = 1·93–6·79, P<0·0001) and coffee consumption (OR = 1·73, 95%CI = 1·04–2·86, P = 0·033) were relevant risk factors for bladder cancer. Conclusions: Specific PAH mixtures may play a relevant role in bladder cancer, although such effect seems to be highly modulated by polymorphisms in genes encoding xenobiotic-metabolizing enzymes. PMID:25291984

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-07-01

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

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

    International Nuclear Information System (INIS)

    Bauschlicher, Charles W. Jr.; Ricca, Alessandra

    2009-01-01

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

  3. Review of PAH contamination in food products and their health hazards.

    Science.gov (United States)

    Bansal, Vasudha; Kim, Ki-Hyun

    2015-11-01

    Public concern over the deleterious effects of polycyclic aromatic hydrocarbons (PAHs) has grown rapidly due to recognition of their toxicity, carcinogenicity, and teratogenicity. The aim of this review is to describe the status of PAH pollution among different food types, the route of dietary intake, measures for its reduction, and legislative approaches to control PAH. To this end, a comprehensive review is outlined to evaluate the status of PAH contamination in many important food categories along with dietary recommendations. Our discussion is also extended to describe preventive measures to reduce PAH in food products to help reduce the risks associated with human intake. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Fast analysis of 29 polycyclic aromatic hydrocarbons (PAHs) and nitro-PAHs with ultra-high performance liquid chromatography-atmospheric pressure photoionization-tandem mass spectrometry

    Science.gov (United States)

    Lung, Shih-Chun Candice; Liu, Chun-Hu

    2015-01-01

    Polycyclic aromatic hydrocarbons (PAHs) and nitro-PAHs are ubiquitous in the environment. Some of them are probable carcinogens and some are source markers. This work presents an ultra-high performance liquid chromatography-atmospheric pressure photoionization-tandem mass spectrometry (UHPLC-APPI-MS/MS) method for simultaneous analysis of 20 PAHs and nine nitro-PAHs. These compounds are separated in 15 minutes in the positive mode and 11 minutes in the negative mode, one half of GC/MS analysis time. Two pairs of precursor/product ions are offered, which is essential for confirmation. This method separates and quantifies benzo[a]pyrene (the most toxic PAHs) and non-priority benzo[e]pyrene (isomers, little toxicity) to avoid overestimation of toxin levels, demonstrating its importance for health-related researches. With 0.5% 2,4-difluoroanisole in chlorobenzene as the dopant, limits of detection of PAHs except acenaphthylene and those of nitro-PAHs except 2-nitrofluoranthene are below 10 pg and 3 pg, respectively, mostly lower than or comparable to those reported using LC-related systems. The responses were linear over two orders of magnitude with fairly good accuracy and precision. Certified reference materials and real aerosol samples were analyzed to demonstrate its applicability. This fast, sensitive, and reliable method is the first UHPLC-APPI-MS/MS method capable of simultaneously analyzing 29 environmentally and toxicologically important PAHs and nitro-PAHs. PMID:26265155

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

    International Nuclear Information System (INIS)

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

    2016-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-11-15

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

  7. Two-way and three-way approaches to ultra high performance liquid chromatography-photodiode array dataset for the quantitative resolution of a two-component mixture containing ciprofloxacin and ornidazole.

    Science.gov (United States)

    Dinç, Erdal; Ertekin, Zehra Ceren; Büker, Eda

    2016-09-01

    Two-way and three-way calibration models were applied to ultra high performance liquid chromatography with photodiode array data with coeluted peaks in the same wavelength and time regions for the simultaneous quantitation of ciprofloxacin and ornidazole in tablets. The chromatographic data cube (tensor) was obtained by recording chromatographic spectra of the standard and sample solutions containing ciprofloxacin and ornidazole with sulfadiazine as an internal standard as a function of time and wavelength. Parallel factor analysis and trilinear partial least squares were used as three-way calibrations for the decomposition of the tensor, whereas three-way unfolded partial least squares was applied as a two-way calibration to the unfolded dataset obtained from the data array of ultra high performance liquid chromatography with photodiode array detection. The validity and ability of two-way and three-way analysis methods were tested by analyzing validation samples: synthetic mixture, interday and intraday samples, and standard addition samples. Results obtained from two-way and three-way calibrations were compared to those provided by traditional ultra high performance liquid chromatography. The proposed methods, parallel factor analysis, trilinear partial least squares, unfolded partial least squares, and traditional ultra high performance liquid chromatography were successfully applied to the quantitative estimation of the solid dosage form containing ciprofloxacin and ornidazole. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

    Science.gov (United States)

    Košnář, Zdeněk; Mercl, Filip; Tlustoš, Pavel

    2018-05-30

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

  9. Decontamination of PAH polluted soils by fungi. Subproject: PAH degradation balance and testing of the extended laboratory process. Final report

    International Nuclear Information System (INIS)

    Martens, R.; Zadrazil, F.; Wolter, M.; Bahadir, M.

    1997-01-01

    The aim of the research project was first to select a fungus with a high potential for mineralization of polycyclic aromatic hydrocarbons (PAH) and a good ability to colonize different soils. The application of this fungus for a degradation of PAH in soil had to be tested. In a screening of 57 white rot fungi the fungus Pleurotus sp. Florida fulfilled these requirements best. In pure culture it was able to metabolize and mineralize highly condensed 4-6 ring PAH to a great extent. For instance, up to 50% of 14 C-pyrene or 39% of 14 C-benzo(a)pyrene was mineralized to 14 CO 2 within 15 weeks. If different carriers for 14 C-pyrene were used the mineralization correlated with the bioavailability, which was characterized by the desorption of the compound from the carriers with water. The mineralization of 14 C-pyrene, 14 C-benz(a)anthracene; 14 C-benzo(a)-pyrene and 14 C-dibenz(a, h)anthracene in native soils showed that a colonization with Pl. sp Florida inhibited the degradation of the less recalcitrant 14 C-pyrene by the indigenous soil microflora. However, the mineralization of the carcinogenic, very recalcitrant and high condensed 14 C-PAH was considerably supported by the fungus. Therefore this capabilities of the fungus could not be proven in a joint medium-scale soil experiment (0.8 m 3 soil) which had been conducted within a parmership with scientists in Jena and an industriell firm. Because of safety aspects only the low condensed less recalcitrant PAH could be applied in this experiment. (orig./MG) [de

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Science.gov (United States)

    Karaca, Gizem

    2016-02-01

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

  12. Interspecies and spatial trends in polycyclic aromatic hydrocarbons (PAHs) in Atlantic and Mediterranean pelagic seabirds

    International Nuclear Information System (INIS)

    Roscales, Jose L.; Gonzalez-Solis, Jacob; Calabuig, Pascual; Jimenez, Begona

    2011-01-01

    PAHs were analyzed in the liver of 5 species of pelagic seabirds (Procellariiformes) from the northeast Atlantic and the Mediterranean. The main objective was to assess the trophic and geographic trends of PAHs in seabirds to evaluate their suitability as bioindicators of chronic marine pollution by these compounds. Although higher levels of PAHs have been described in the Mediterranean compared to other oceanic regions, we did not find significant spatial patterns and observed only minor effects of the geographic origin on seabird PAHs. However, we found significant higher PAH levels in petrel compared to shearwater species, which could be related to differences in their exploitation of mesopelagic and epipelagic resources, respectively, and the vertical dynamic of PAHs in the water column. Overall, although this study enhances the need of multi-species approaches to show a more comprehensive evaluation of marine pollution, seabirds emerged as poor indicators of pelagic chronic PAH levels. - Highlights: → PAHs in pelagic seabirds show specific inter-species patterns related to trophic ecology. → Geographic origin shows a minor effect over PAH levels in pelagic seabirds. → Pelagic seabirds seem to be poor indicators of chronic PAH levels. - PAH levels in Atlantic and Mediterranean pelagic seabirds show specific inter-species patterns related to trophic ecology but a minor influence of their geographic origin.

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

    International Nuclear Information System (INIS)

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

    2015-01-01

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

  14. Watershed-scale modeling on the fate and transport of polycyclic aromatic hydrocarbons (PAHs)

    International Nuclear Information System (INIS)

    Ligaray, Mayzonee; Baek, Sang Soo; Kwon, Hye-Ok; Choi, Sung-Deuk; Cho, Kyung Hwa

    2016-01-01

    PAHs are potentially carcinogenic substances that are persistent in the environment. Increasing concentrations of PAHs were observed due to rapid urbanization, thus; monitoring PAHs concentrations is necessary. However, it is expensive to conduct intensive monitoring activities of a large number of PAHs. This study addressed this issue by developing a multimedia model coupled with a hydrological model (i.e., Soil and Water Assessment Tool (SWAT)) for Taehwa River (TR) watershed in Ulsan, the industrial capital of South Korea. The hydrologic module of the SWAT was calibrated, and further used to simulate the fate and transport of PAHs in soil and waterbody. The model demonstrated that the temporal or seasonal variation of PAHs in soil and waterbody can be well reproduced. Meanwhile, the spatial distribution of PAHs showed that urban areas in TR watershed have the highest PAH loadings compared to rural areas. Sensitivity analyses of the PAH soil and PAH water parameters were also able to determine the critical processes in TR watershed: degradation, deposition, volatilization, and wash off mechanism. We hope that this model will be able to aid the stakeholders in: regulating PAH concentrations emitted by various sources; and also apply the model to other Persistent Organic Pollutants (POPs).

  15. Watershed-scale modeling on the fate and transport of polycyclic aromatic hydrocarbons (PAHs)

    Energy Technology Data Exchange (ETDEWEB)

    Ligaray, Mayzonee; Baek, Sang Soo [School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology, UNIST-gil 50, Ulsan 44919 (Korea, Republic of); Kwon, Hye-Ok [Disaster Scientific Investigation Division, National Disaster Management Research Institute, 365 Jongga-ro Jung-gu, Ulsan 44538 (Korea, Republic of); Choi, Sung-Deuk, E-mail: sdchoi@unist.ac.kr [School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology, UNIST-gil 50, Ulsan 44919 (Korea, Republic of); Cho, Kyung Hwa, E-mail: khcho@unist.ac.kr [School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology, UNIST-gil 50, Ulsan 44919 (Korea, Republic of)

    2016-12-15

    PAHs are potentially carcinogenic substances that are persistent in the environment. Increasing concentrations of PAHs were observed due to rapid urbanization, thus; monitoring PAHs concentrations is necessary. However, it is expensive to conduct intensive monitoring activities of a large number of PAHs. This study addressed this issue by developing a multimedia model coupled with a hydrological model (i.e., Soil and Water Assessment Tool (SWAT)) for Taehwa River (TR) watershed in Ulsan, the industrial capital of South Korea. The hydrologic module of the SWAT was calibrated, and further used to simulate the fate and transport of PAHs in soil and waterbody. The model demonstrated that the temporal or seasonal variation of PAHs in soil and waterbody can be well reproduced. Meanwhile, the spatial distribution of PAHs showed that urban areas in TR watershed have the highest PAH loadings compared to rural areas. Sensitivity analyses of the PAH soil and PAH water parameters were also able to determine the critical processes in TR watershed: degradation, deposition, volatilization, and wash off mechanism. We hope that this model will be able to aid the stakeholders in: regulating PAH concentrations emitted by various sources; and also apply the model to other Persistent Organic Pollutants (POPs).

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

    International Nuclear Information System (INIS)

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

    2012-01-01

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

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

    International Nuclear Information System (INIS)

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

    2006-01-01

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

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

    International Nuclear Information System (INIS)

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

    2010-01-01

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

  19. Enrichment behavior and transport mechanism of soil-bound PAHs during rainfall-runoff events.

    Science.gov (United States)

    Zheng, Yi; Luo, Xiaolin; Zhang, Wei; Wu, Bin; Han, Feng; Lin, Zhongrong; Wang, Xuejun

    2012-12-01

    Polycyclic Aromatic Hydrocarbons (PAHs) transported by surface runoff result in nonpoint source pollution and jeopardize aquatic ecosystems. The transport mechanism of PAHs during rainfall-runoff events has been rarely studied regarding pervious areas. An experimental system was setup to simulate the runoff pollution process on PAHs-contaminated soil. The enrichment behavior of soil-bound PAHs was investigated. The results show that soil organic matters (SOM), rather than clay particles, seem to be the main carrier of PAHs. The enrichment is highly conditioned on runoff and erosion processes, and its magnitude varies among PAH compounds. It is not feasible to build a simple and universal relationship between enrichment ratio and sediment discharge following the traditional enrichment theory. To estimate the flux of PAHs from pervious areas, soil erosion process has to be clearly understood, and both organic carbon content and composition of SOM should be factored into the calculation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Influence of smoking parameters on the concentration of polycyclic aromatic hydrocarbons (PAHs) in Danish smoked fish

    DEFF Research Database (Denmark)

    Duedahl-Olesen, Lene; Christensen, J. H.; Højgård, A.

    2010-01-01

    were also tested in a pilot plant study with smoked trout as a model fish. In addition to confirming that increased combustion temperatures and usage of common alder in comparison with beech increased Sigma PAH25, it was also revealed that the PAH concentration decreased in the order fish skin >> outer......A new method for the analysis of 25 polycyclic aromatic hydrocarbon (PAH) compounds in fish was developed, validated, and used for the quantification of PAHs in 180 industrially smoked fish products. The method included pressurized liquid extraction, gel-permeation chromatography (Bio-beads S-X3...... smoking, and for other fish species direct smoking leads to higher sigma PAH25 than indirect smoking. Also, the usage of common alder increases the PAH contamination compared with beech. The effects of smoking time, combustion temperatures, and two types of smoke-generating material on the Sigma PAH25...

  1. Ca2+ promoted the low transformation efficiency of plasmid DNA exposed to PAH contaminants.

    Directory of Open Access Journals (Sweden)

    Fuxing Kang

    Full Text Available The effects of interactions between genetic materials and polycyclic aromatic hydrocarbons (PAHs on gene expression in the extracellular environment remain to be elucidated and little information is currently available on the effect of ionic strength on the transformation of plasmid DNA exposed to PAHs. Phenanthrene and pyrene were used as representative PAHs to evaluate the transformation of plasmid DNA after PAH exposure and to determine the role of Ca(2+ during the transformation. Plasmid DNA exposed to the test PAHs demonstrated low transformation efficiency. In the absence of PAHs, the transformation efficiency was 4.7 log units; however, the efficiency decreased to 3.72-3.14 log units with phenanthrene/pyrene exposures of 50 µg · L(-1. The addition of Ca(2+ enhanced the low transformation efficiency of DNA exposed to PAHs. Based on the co-sorption of Ca(2+ and phenanthrene/pyrene by DNA, we employed Fourier-transform infrared spectroscopy (FTIR, X-ray photoelectron spectroscopy (XPS, and mass spectrometry (MS to determine the mechanisms involved in PAH-induced DNA transformation. The observed low transformation efficiency of DNA exposed to either phenanthrene or pyrene can be attributed to a broken hydrogen bond in the double helix caused by planar PAHs. Added Ca(2+ formed strong electrovalent bonds with "-POO(--" groups in the DNA, weakening the interaction between PAHs and DNA based on weak molecular forces. This decreased the damage of PAHs to hydrogen bonds in double-stranded DNA by isolating DNA molecules from PAHs and consequently enhanced the transformation efficiency of DNA exposed to PAH contaminants. The findings provide insight into the effects of anthropogenic trace PAHs on DNA transfer in natural environments.

  2. Comparing PAH availability from manufactured gas plant soils and sediments with chemical and biological tests. 1. PAH release during water desorption and supercritical carbon dioxide extraction.

    Science.gov (United States)

    Hawthorne, Steven B; Poppendieck, Dustin G; Grabanski, Carol B; Loehr, Raymond C

    2002-11-15

    Soil and sediment samples from oil gas (OG) and coal gas (CG) manufactured gas plant (MGP) sites were selected to represent a range of PAH concentrations (150-40,000 mg/kg) and sample matrix compositions. Samples varied from vegetated soils to lampblack soot and had carbon contents from 3 to 87 wt %. SFE desorption (120 min) and water/XAD2 desorption (120 days) curves were determined and fit with a simple two-site model to determine the rapid-released fraction (F) for PAHs ranging from naphthalene to benzo[ghi]perylene. F values varied greatly among the samples, from ca. 10% to >90% for the two- and three-ring PAHs and from <1% to ca. 50% for the five- and six-ring PAHs. Release rates did not correlate with sample matrix characteristics including PAH concentrations, elemental composition (C, H, N, S), or "hard" and "softs" organic carbon, indicating that PAH release cannot easily be estimated on the basis of sample matrix composition. Fvalues for CG site samples obtained with SFE and water desorption agreed well (linear correlation coefficient, r2 = 0.87, slope = 0.93), but SFE yielded higher F values for the OG samples. These behaviors were attributed to the stronger ability of carbon dioxide than water to desorb PAHs from the highly aromatic (hard) carbon of the OG matrixes, while carbon dioxide and water showed similar abilities to desorb PAHs from the more polar (soft) carbon of the CG samples. The combined SFE and water desorption approaches should improve the understanding of PAH sequestration and release from contaminated soils and sediments and provide the basis for subsequent studies using the same samples to compare PAH release with PAH availability to earthworms.

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

    Science.gov (United States)

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

    2015-04-01

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

  4. Proportional counter with uniform electric field with Penning's mixture

    International Nuclear Information System (INIS)

    Pawlowski, Z.; Marzec, J.; Zaremba, K.

    1984-01-01

    Some calculations are given and the design of proportional counters with a homogeneous electric field filled with Penning's mixtures, which ensure the best energy resolution is described. The counters with mixtures of Ne+Ar, Ne+CH 4 , Ne+CO 2 and Ar+C 2 H 2 have been checked. The admixtures (Ar, CH 4 , CO 2 , C 2 H 2 ) constitute from 0.1 to 2%, with pressure from 125 Tr to 760 Torr. The best energy resolution has been obtained for the mixture of Ne+1%CH 4 at the pressure of 190 Torr

  5. Perception of trigeminal mixtures.

    Science.gov (United States)

    Filiou, Renée-Pier; Lepore, Franco; Bryant, Bruce; Lundström, Johan N; Frasnelli, Johannes

    2015-01-01

    The trigeminal system is a chemical sense allowing for the perception of chemosensory information in our environment. However, contrary to smell and taste, we lack a thorough understanding of the trigeminal processing of mixtures. We, therefore, investigated trigeminal perception using mixtures of 3 relatively receptor-specific agonists together with one control odor in different proportions to determine basic perceptual dimensions of trigeminal perception. We found that 4 main dimensions were linked to trigeminal perception: sensations of intensity, warmth, coldness, and pain. We subsequently investigated perception of binary mixtures of trigeminal stimuli by means of these 4 perceptual dimensions using different concentrations of a cooling stimulus (eucalyptol) mixed with a stimulus that evokes warmth perception (cinnamaldehyde). To determine if sensory interactions are mainly of central or peripheral origin, we presented stimuli in a physical "mixture" or as a "combination" presented separately to individual nostrils. Results showed that mixtures generally yielded higher ratings than combinations on the trigeminal dimensions "intensity," "warm," and "painful," whereas combinations yielded higher ratings than mixtures on the trigeminal dimension "cold." These results suggest dimension-specific interactions in the perception of trigeminal mixtures, which may be explained by particular interactions that may take place on peripheral or central levels. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. Evaluation of hydrophobicity in PAH-contaminated soils during phytoremediation

    International Nuclear Information System (INIS)

    Cofield, Naressa; Banks, M. Katherine; Schwab, A. Paul

    2007-01-01

    The impact of recalcitrant organic compounds on soil hydrophobicity was evaluated in contaminated soil from a manufactured gas plant site following 12 months of phytoremediation. Significant reduction in soil wetting and water retention was observed in contaminated soil compared to an uncontaminated control. Phytoremediation was effective at reducing total PAHs by 69% with corresponding changes in soil classification from extremely hydrophobic (initial sample) to moderately-strongly hydrophobic (planted) and hydrophilic-very hydrophilic (unplanted) after 12 months. The greatest reduction in soil hydrophobicity was observed in the unplanted, unfertilized treatments that had the lowest removal rate of PAHs. The presence of plants may contribute to hydrophobicity in contaminated soil. - The presence of recalcitrant hydrophobic organic pollutants may enhance soil hydrophobicity

  7. Heavy metals, PAHs and toxicity in stormwater wet detention ponds

    DEFF Research Database (Denmark)

    Wium-Andersen, Tove; Nielsen, Asbjørn Haaning; Hvitved-Jacobsen, Thorkild

    2011-01-01

    Concentrations of 6 different heavy metals and total Polycyclic Aromatic Hydrocarbons (PAH) were determined in stormwater runoff and in the pond water of two Danish wet detention ponds. The pond water samples were analyzed for toxic effects, using the algae Selenastrum capricornutum as a test...... organism. Stormwater and pond water from a catchment with light industry showed high levels of heavy metals, especially zinc and copper. The pond water showed high toxic effects and copper were found to be the main toxicant. Additionally, a large part of the copper was suspected to be complex bound......, reducing the potential toxicity of the metal. Another catchment (residential) produced stormwater and pond water with moderate concentration of heavy metals. The pond water occasionally showed toxic effects but no correlation between heavy metals and toxicity was identified. PAHs concentrations were...

  8. Iterative Mixture Component Pruning Algorithm for Gaussian Mixture PHD Filter

    Directory of Open Access Journals (Sweden)

    Xiaoxi Yan

    2014-01-01

    Full Text Available As far as the increasing number of mixture components in the Gaussian mixture PHD filter is concerned, an iterative mixture component pruning algorithm is proposed. The pruning algorithm is based on maximizing the posterior probability density of the mixture weights. The entropy distribution of the mixture weights is adopted as the prior distribution of mixture component parameters. The iterative update formulations of the mixture weights are derived by Lagrange multiplier and Lambert W function. Mixture components, whose weights become negative during iterative procedure, are pruned by setting corresponding mixture weights to zeros. In addition, multiple mixture components with similar parameters describing the same PHD peak can be merged into one mixture component in the algorithm. Simulation results show that the proposed iterative mixture component pruning algorithm is superior to the typical pruning algorithm based on thresholds.

  9. Removal of Heavy Metals and PAH in Retention Basins

    DEFF Research Database (Denmark)

    Larsen, Torben; Neerup-Jensen, Ole

    2004-01-01

    Solid seperation in retention basins is strongly non-linear and depends significantly on the flow rate and the settling characteristics of the particles. Accordingly the calculation of the annual loads of pollutants from storm overflows including basins is rather complex and time consuming...... in order to calculate annual loads of pollutants from urban catchments. The study cover Cd, Cu, Ni, Pb, Zn and PAH....

  10. Distribution Pattern of Polyaromatic Hydrocarbons (PAHs) in Soils in ...

    African Journals Online (AJOL)

    Distribution Pattern of Polyaromatic Hydrocarbons (PAHs) in Soils in the Vicinity of Fuel Stations in Abraka, Nigeria. ... (0.00191mg.kg-1). Investigation also reveals that all tested samples are contaminated, with mean values ranging between 0.000207±0.00026mg.kg-1 and 0.002123±0.00303mg.kg-1. Similarly, spearmen's ...

  11. Reduction of Ferrrihydrite and Akaganeite by Shewanella alga (PAH93)

    Science.gov (United States)

    Jung, M.; Kim, Y.; Lee, Y.; Kwon, K.; Roh, Y.

    2009-12-01

    Shewanella species are capable of oxidizing diverse organic acids coupled to reducing Fe(III) (oxy)hydroxides to crystalline Fe(II)-containing phases such as magnetite, siderite, and vivianite. The objective of this study was to examine reduction of ferrihydrite and akaganeite as the electron acceptors using various organic acids as the electron donors by Shewanella alga (PAH93) isolated from Yeosu, South Korea. Microbial reduction of akaganeite (40 mM) and ferrihydrite (40 mM) was examined using acetate (10 mM), glucose (10 mM), and lactate (10 mM) as electron donors at room temperature. Ferrozine method was used to analyze both water soluble and HCl soluble Fe(II) concentrations during the microbial Fe(III) reduction. XRD and TEM-EDX analyses were used to characterize biominerals formed by PAH93. PAH93 was completely reduced ferrihydrite to Fe(II), which transformed as siderite (FeCO3). PAH93 was oxidized acetate, glucose, and lactate coupled to reducing akaganeite to magnetite or green rust. Microbial reduction of ferrihydrite resulted in higher soluble Fe(II) concentration (446 - 498 mg/L) than the reduction of akaganeite (255 - 284 mg/L) within 6 days of incubation. For 21 days of incubation, souble Fe(II) concentration during akaganeite reduction (945 - 1316 mg/L) was higher than ferrihydrite reduction (120 - 738 mg/L). It may be attributed to the differences of crystallinity of the iron minerals used for microbial iron reduction. This study indicates types of the electron acceptors, ferrihydrite and akaganeite, affect Fe(II) reduction rate and types of the biotransformed minerals.

  12. Heterogeneous ozonation reactions of PAHs and fatty acid methyl esters in biodiesel particulate matter

    Science.gov (United States)

    Kasumba, John; Holmén, Britt A.

    2018-02-01

    Numerous studies have examined the oxidation of PAHs found in diesel particulate matter (PM) by ozone, but no studies have investigated the ozone oxidation of biodiesel exhaust PM. Fatty acid methyl esters (FAMEs), found in high abundance in biodiesel PM, can potentially alter the kinetics of the reactions between atmospheric oxidants such as ozone and particle-phase PAHs. In this study, the heterogeneous reactivity of 16 EPA PAHs upon 24 h exposure to 0.4 ppm ozone in the presence (PAH + FAMES) and absence (PAH-only) of FAMEs was investigated at room temperature and 50% relative humidity. The ozone-reactivity of the PAHs detected in 20% biodiesel (B20) exhaust PM was also investigated. In the absence of FAMEs, the pseudo-first order ozone reaction rate constant, kO 3 , of PAHs varied from 0.086 ± 0.030 hr-1 (chrysene) to 0.184 ± 0.078 hr-1 (anthracene). In the presence of FAMEs, kO 3 of the PAHs varied between 0.013 ± 0.012 hr-1 (benzo[b]fluoranthene) and 0.168 ± 0.028 hr-1 (benzo[a]pyrene), and with the exception of benzo[a]pyrene, the kO 3 of PAHs were 1.2-8 times lower compared to those obtained during the PAH-only ozone exposure. Only one PAH, benzo[a]pyrene (BaP), did not show a significant change in kO3 with addition of FAMEs. Phenanthrene, fluoranthene, and pyrene, the only PAHs detected in the B20 PM, had kO 3 values about 4 times lower in B20 PM than those obtained when spiked PAHs-only were exposed to ozone. The kO 3 values of phenanthrene and fluoranthene in the B20 PM were 2 times higher than rates obtained when the PAH mix was exposed to ozone in the presence of the FAMEs. In contrast, pyrene's kO 3 in the B20 PM was about 2 times lower than that obtained for the PAH + FAMEs exposure. Observed differences in PAH behavior demonstrate individual PAH heterogeneous reactivity with gas-phase ozone is sensitive to PAH (vapor pressure, solubility/sorption to matrix components, chemical reactivity) as well as substrate properties (PAH and O3 diffusivity

  13. Extraction agents for the removal of polycyclic aromatic hydrocarbons (PAHs) from soil in soil washing technologies

    International Nuclear Information System (INIS)

    Lau, Ee Von; Gan, Suyin; Ng, Hoon Kiat; Poh, Phaik Eong

    2014-01-01

    Polycyclic aromatic hydrocarbons (PAHs) in soil have been recognised as a serious health and environmental issue due to their carcinogenic, mutagenic and teratogenic properties. One of the commonly employed soil remediation techniques to clean up such contamination is soil washing or solvent extraction. The main factor which governs the efficiency of this process is the solubility of PAHs in the extraction agent. Past field-scale soil washing treatments for PAH-contaminated soil have mainly employed organic solvents or water which is either toxic and costly or inefficient in removing higher molecular weight PAHs. Thus, the present article aims to provide a review and discussion of the alternative extraction agents that have been studied, including surfactants, biosurfactants, microemulsions, natural surfactants, cyclodextrins, vegetable oil and solution with solid phase particles. These extraction agents have been found to remove PAHs from soil at percentages ranging from 47 to 100% for various PAHs. -- Highlights: • The alternative and advancement in extraction agents to remove PAHs from soil using soil washing technology is summarised. • The soil regulations for PAH level in various countries are summarized for reference to researchers. • The concentration levels of PAHs in soil at present and the need for soil remediation is presented. -- The efficiency of the extraction agent plays a significant role in soil washing of PAH-contaminated soil

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

    Science.gov (United States)

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

    2014-12-01

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

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

    International Nuclear Information System (INIS)

    Prajapati, Santosh Kumar; Tripathi, B.D.

    2008-01-01

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

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

    Science.gov (United States)

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

    2014-12-24

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

  17. Current Approaches to the Treatment of Systemic-Sclerosis-Associated Pulmonary Arterial Hypertension (SSc-PAH).

    Science.gov (United States)

    Sobanski, Vincent; Launay, David; Hachulla, Eric; Humbert, Marc

    2016-02-01

    Pulmonary arterial hypertension (PAH) is a severe condition causing significant morbidity and mortality in patients with systemic sclerosis (SSc). Despite the use of specific treatments, SSc-PAH survival remains poorer than in idiopathic PAH (IPAH). Recent therapeutic advances in PAH show a lower magnitude of response in SSc-PAH and a higher risk of adverse events, as compared to IPAH. The multifaceted underlying mechanisms and the multisystem nature of SSc probably explain part of the worse outcomes in SSc-PAH compared to IPAH. This review describes the current management of SSc-PAH with an emphasis on the impact of the different organ involvements in the prognosis and treatment response. An earlier detection of PAH and a better characterization of the clinical phenotypes of SSc-PAH are warranted in clinical practice and future trials. Determinants of prognosis, surrogate markers of clinical improvement or worsening, and relevance of the common endpoints used in clinical trials should be evaluated in this specific population. A multidisciplinary approach in expert referral centers is mandatory for SSc-PAH management.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-05-15

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

  19. Spatial and temporal distribution of polycyclic aromatic hydrocarbons (PAHs) in the atmosphere of Xiamen, China

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Jinping [Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Guangdong Environmental Monitoring Centre, Guangzhou 510308 (China); Zhang, Fuwang; Xu, Lingling [Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Graduate School of Chinese Academy of Sciences, Beijing 100049 (China); Chen, Jinsheng, E-mail: jschen@iue.ac.cn [Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Xu, Ya [Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Graduate School of Chinese Academy of Sciences, Beijing 100049 (China)

    2011-11-15

    An intensive sampling program was conducted from October 2008 to September 2009 at the five different environmental sites in Xiamen, Fujian Province, to study the spatial and temporal characteristics of Polycyclic Aromatic Hydrocarbons (PAHs) in the gaseous and particulate phase, respectively. The PAHs concentrations at different sites were quite distinct during four seasons. The average concentrations of PAHs in winter were about 8.4 times higher than those in spring, and the concentrations of background were 0.56 times lower than those of industrial area. In addition, the higher temperature in summer affected the particle/gas partitioning of PAHs and led to the higher concentrations of gaseous PAHs. Diagnostic ratios of PAHs, which were employed to indicate the primary sources of PAHs in Xiamen, showed that the traffic vehicle exhaust was the largest contributor and the primary source for PAHs in Xiamen, especially in urban area; while the stationary combustion processes, such as petrochemical factories and power plants, were mainly responsible for PAHs sources in the industrial areas. The health risk of PAHs in the particulate phase was higher than those of the gaseous phase at the five sampling sites. The average toxic equivalent (BaP{sub eq}) of the benzo[a]pyrene values for PAHs were 0.14, 0.32, 1.38 and 3.59 ng m{sup -3} in spring, summer, autumn and winter, respectively. Furthermore, the results of average BaP{sub eq} in all four seasons indicated that the health risks of particulate PAHs were higher than those of the gaseous PAHs at different sampling sites.

  20. Using slow-release permanganate candles to remediate PAH-contaminated water.

    Science.gov (United States)

    Rauscher, Lindy; Sakulthaew, Chainarong; Comfort, Steve

    2012-11-30

    Surface waters impacted by urban runoff in metropolitan areas are becoming increasingly contaminated with polycyclic aromatic hydrocarbons (PAHs). Slow-release oxidant candles (paraffin-KMnO(4)) are a relatively new technology being used to treat contaminated groundwater and could potentially be used to treat urban runoff. Given that these candles only release permanganate when submerged, the ephemeral nature of runoff events would influence when the permanganate is released for treating PAHs. Our objective was to determine if slow-release permanganate candles could be used to degrade and mineralize PAHs. Batch experiments quantified PAH degradation rates in the presence of the oxidant candles. Results showed most of the 16 PAHs tested were degraded within 2-4 h. Using (14)C-labled phenanthrene and benzo(a)pyrene, we demonstrated that the wax matrix of the candle initially adsorbs the PAH, but then releases the PAH back into solution as transformed, more water soluble products. While permanganate was unable to mineralize the PAHs (i.e., convert to CO(2)), we found that the permanganate-treated PAHs were much more biodegradable in soil microcosms. To test the concept of using candles to treat PAHs in multiple runoff events, we used a flow-through system where urban runoff water was pumped over a miniature candle in repetitive wet-dry, 24-h cycles. Results showed that the candle was robust in removing PAHs by repeatedly releasing permanganate and degrading the PAHs. These results provide proof-of-concept that permanganate candles could potentially provide a low-cost, low-maintenance approach to remediating PAH-contaminated water. Copyright © 2012 Elsevier B.V. All rights reserved.

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

    International Nuclear Information System (INIS)

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

    2013-01-01

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

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

    Science.gov (United States)

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

    2015-10-01

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

  3. Experimental increase in availability of a PAH complex organic contamination from an aged contaminated soil: Consequences on biodegradation

    International Nuclear Information System (INIS)

    Cébron, Aurélie; Faure, Pierre; Lorgeoux, Catherine; Ouvrard, Stéphanie; Leyval, Corinne

    2013-01-01

    Although high PAH content and detection of PAH-degraders, the PAH biodegradation is limited in aged-contaminated soils due to low PAH availability (i.e., 1%). Here, we tried to experimentally increase the soil PAH availability by keeping both soil properties and contamination composition. Organic extract was first removed and then re-incorporated in the raw soil as fresh contaminants. Though drastic, this procedure only allowed a 6-time increase in the PAH availability suggesting that the organic constituents more than ageing were responsible for low availability. In the re-contaminated soil, the mineralization rate was twice more important, the proportion of 5–6 cycles PAH was higher indicating a preferential degradation of lower molecular weight PAH. The extraction treatment induced bacterial and fungal community structures modifications, Pseudomonas and Fusarium solani species were favoured, and the relative quantity of fungi increased. In re-contaminated soil the percentage of PAH-dioxygenase gene increased, with 10 times more Gram negative representatives. -- Highlights: ► Re-incorporation of soil organic extract increased 6-times the PAH availability. ► Complexity of organic contamination is the main driver of PAH availability. ► Biodegradation of PAH with less than 5-cycles increased with increasing PAH availability. ► Pseudomonas and Fusarium species are favoured when PAH availability increased. -- More than ageing, the complexity of organic contamination is the main driver of PAH availability

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

    Science.gov (United States)

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

    2011-01-15

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

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

    International Nuclear Information System (INIS)

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

    1987-01-01

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

  6. Using slow-release permanganate candles to remediate PAH-contaminated water

    Energy Technology Data Exchange (ETDEWEB)

    Rauscher, Lindy, E-mail: purplerauscher@neb.rr.com [School of Natural Resources, University of Nebraska, Lincoln, NE 68583-0915 (United States); Sakulthaew, Chainarong, E-mail: chainarong@huskers.unl.edu [School of Natural Resources, University of Nebraska, Lincoln, NE 68583-0915 (United States); Department of Veterinary Technology, Kasetsart University, Bangkok 10900 (Thailand); Comfort, Steve, E-mail: scomfort1@unl.edu [School of Natural Resources, University of Nebraska, Lincoln, NE 68583-0915 (United States)

    2012-11-30

    Highlights: Black-Right-Pointing-Pointer We quantified the efficacy of slow-release permanganate-paraffin candles to degrade and mineralize PAHs. Black-Right-Pointing-Pointer {sup 14}C-labeled PAHs were used to quantify both adsorption and transformation. Black-Right-Pointing-Pointer Permanganate-treated PAHs were more biodegradable in soil microcosms. Black-Right-Pointing-Pointer A flow-through candle system was used to quantify PAH removal in urban runoff. - Abstract: Surface waters impacted by urban runoff in metropolitan areas are becoming increasingly contaminated with polycyclic aromatic hydrocarbons (PAHs). Slow-release oxidant candles (paraffin-KMnO{sub 4}) are a relatively new technology being used to treat contaminated groundwater and could potentially be used to treat urban runoff. Given that these candles only release permanganate when submerged, the ephemeral nature of runoff events would influence when the permanganate is released for treating PAHs. Our objective was to determine if slow-release permanganate candles could be used to degrade and mineralize PAHs. Batch experiments quantified PAH degradation rates in the presence of the oxidant candles. Results showed most of the 16 PAHs tested were degraded within 2-4 h. Using {sup 14}C-labled phenanthrene and benzo(a)pyrene, we demonstrated that the wax matrix of the candle initially adsorbs the PAH, but then releases the PAH back into solution as transformed, more water soluble products. While permanganate was unable to mineralize the PAHs (i.e., convert to CO{sub 2}), we found that the permanganate-treated PAHs were much more biodegradable in soil microcosms. To test the concept of using candles to treat PAHs in multiple runoff events, we used a flow-through system where urban runoff water was pumped over a miniature candle in repetitive wet-dry, 24-h cycles. Results showed that the candle was robust in removing PAHs by repeatedly releasing permanganate and degrading the PAHs. These results provide

  7. Using slow-release permanganate candles to remediate PAH-contaminated water

    International Nuclear Information System (INIS)

    Rauscher, Lindy; Sakulthaew, Chainarong; Comfort, Steve

    2012-01-01

    Highlights: ► We quantified the efficacy of slow-release permanganate-paraffin candles to degrade and mineralize PAHs. ► 14 C-labeled PAHs were used to quantify both adsorption and transformation. ► Permanganate-treated PAHs were more biodegradable in soil microcosms. ► A flow-through candle system was used to quantify PAH removal in urban runoff. - Abstract: Surface waters impacted by urban runoff in metropolitan areas are becoming increasingly contaminated with polycyclic aromatic hydrocarbons (PAHs). Slow-release oxidant candles (paraffin–KMnO 4 ) are a relatively new technology being used to treat contaminated groundwater and could potentially be used to treat urban runoff. Given that these candles only release permanganate when submerged, the ephemeral nature of runoff events would influence when the permanganate is released for treating PAHs. Our objective was to determine if slow-release permanganate candles could be used to degrade and mineralize PAHs. Batch experiments quantified PAH degradation rates in the presence of the oxidant candles. Results showed most of the 16 PAHs tested were degraded within 2–4 h. Using 14 C-labled phenanthrene and benzo(a)pyrene, we demonstrated that the wax matrix of the candle initially adsorbs the PAH, but then releases the PAH back into solution as transformed, more water soluble products. While permanganate was unable to mineralize the PAHs (i.e., convert to CO 2 ), we found that the permanganate-treated PAHs were much more biodegradable in soil microcosms. To test the concept of using candles to treat PAHs in multiple runoff events, we used a flow-through system where urban runoff water was pumped over a miniature candle in repetitive wet–dry, 24-h cycles. Results showed that the candle was robust in removing PAHs by repeatedly releasing permanganate and degrading the PAHs. These results provide proof-of-concept that permanganate candles could potentially provide a low-cost, low-maintenance approach to

  8. The Role of Human Aldo-Keto Reductases (AKRs in the Metabolic Activation and Detoxication of Polycyclic Aromatic Hydrocarbons: Interconversion of PAH-catechols and PAH o-Quinones

    Directory of Open Access Journals (Sweden)

    Li eZhang

    2012-11-01

    Full Text Available Polycyclic aromatic hydrocarbons (PAH are ubiquitous environmental pollutants. They are procarcinogens requiring metabolic activation to elicit their deleterious effects. Aldo-keto reductases (AKR catalyze the oxidation of proximate carcinogenic PAH trans-dihydrodiols to yield electrophilic and redox-active PAH o-quiniones. AKRs are also found to be capable of reducing PAH o-quinones to form PAH catechols. The interconversion of o-quinones and catechols results in the redox cycling of PAH o-quinones to give rise to the generation of reactive oxygen species and subsequent oxidative DNA damage. On the other hand, PAH catechols can be intercepted through phase II metabolism by which PAH o-quinones could be detoxified and eliminated. The aim of the present review is to summarize the role of human AKRs in the metabolic activation/detoxication of PAH and the relevance of phase II conjugation reactions to human lung carcinogenesis.

  9. Availability of polycyclic aromatic hydrocarbons to earthworms (Eisenia andrei, Oligochaeta) in field-polluted soils and soil-sediment mixtures.

    Science.gov (United States)

    Jager, Tjalling; Baerselman, Rob; Dijkman, Ellen; de Groot, Arthur C; Hogendoorn, Elbert A; de Jong, Ad; Kruitbosch, Jantien A W; Peijnenburg, Willie J G M

    2003-04-01

    The bioavailability of polycyclic aromatic hydrocarbons (PAHs) for earthworms (Eisenia andrei) was experimentally determined in seven field-polluted soils and 15 soil-sediment mixtures. The pore-water concentration of most PAHs was higher than predicted. However, most of the compound was associated with dissolved organic carbon (DOC) and not directly available for uptake by earthworms. The apparent sorption could be reasonably predicted on the basis of interactions with DOC; however, the biota-soil accumulation factors (BSAFs) for earthworms were up to two orders of magnitude lower than predicted by equilibrium partitioning. The large variability between sites was not fully explained by differences in sorption. Experimental results indicate that the pool of freely dissolved PAHs in the pore water became partially depleted because of uptake by the earthworms and that bioaccumulation is thus also influenced by the kinetics of PAH desorption and mass transport. A pilot study with Lumbricus rubellus showed that steady-state body residues were well correlated to E. andrei. Current results show that depositing dredge spoil on land may lead to increased bioavailability of the lower-molecular-weight PAHs. However, risk assessment can conservatively rely on equilibrium partitioning, but accurate prediction requires quantification of the kinetics of bioavailability.

  10. 1-hydroxypyrene as a biomarker of PAH exposure in the marine invertebrates N. diversicolor

    DEFF Research Database (Denmark)

    Tairova, Zhanna; Giessing, Anders; Hansen, Rikke

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

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

    Science.gov (United States)

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

    2018-07-03

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

  12. PAH dissipation in a contaminated river sediment under oxic and anoxic conditions

    International Nuclear Information System (INIS)

    Quantin, C.; Joner, E.J.; Portal, J.M.; Berthelin, J.

    2005-01-01

    A batch experiment was conducted to compare PAH degradation in a polluted river sediment under aerobic and anaerobic conditions, and to investigate whether input of fresh organic material (cellulose) could enhance such degradation. All measurements were checked against abiotic control treatments to exclude artifacts of sample preparation and non-biological processes like aging. Three- and four-ring PAHs could be degraded by the indigenous microbial community under aerobic conditions, but anaerobic metabolism based on iron and sulphate reduction was not coupled with PAH degradation of even the simplest 3-ring compounds like phenanthrene. Cellulose addition stimulated both aerobic and anaerobic respiration, but had no effect on PAH dissipation. We conclude that natural attenuation of PAHs in polluted river sediments under anaerobic conditions is exceedingly slow. Dredging and biodegradation on land under aerobic conditions would be required to safely remediate and restore polluted sites. - Natural attenuation of PAHs under anaerobic conditions is exceedingly slow

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

    Directory of Open Access Journals (Sweden)

    Günay Kural

    2018-04-01

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

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

    International Nuclear Information System (INIS)

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

    2005-01-01

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

  15. Distribution and Source of Sedimentary Polycyclic Aromatic Hydrocarbon (PAHs in River Sediment of Jakarta

    Directory of Open Access Journals (Sweden)

    Rinawati Rinawati

    2017-11-01

    Full Text Available In this study, the distribution and source identification of sedimentary PAHs from 13 rivers running through Jakarta City were investigated. Freeze-dried sediment samples were extracted by pressurized fluid extraction and purified by two-step of column chromatography. PAHs were identified and quantified by gas chromatography-mass spectrometry (GC-MS. High concentrations of PAHs, ranging from 1992 to 17635 ng/g-dw, were observed at all sampling locations. Ratios of alkylated PAHs to parent PAHs exhibited both petrogenic and pyrogenic signatures with predominantly petrogenic inputs. High hopanne concentrations (4238-40375 ng/g dry sediment supported the petrogenic input to Jakarta’s rivers. The high concentration of PAHs is indicator for organic micropollutant in the aquatic urban environment in Jakarta that may have the potential to cause adverse effect to the environment.

  16. Bacteria from wheat and cucurbit plant roots metabolize PAHs and aromatic root exudates: Implications for rhizodegradation.

    Science.gov (United States)

    Ely, Cairn S; Smets, Barth F

    2017-10-03

    The chemical interaction between plants and bacteria in the root zone can lead to soil decontamination. Bacteria that degrade polycyclic aromatic hydrocarbons (PAHs) have been isolated from the rhizospheres of plant species with varied biological traits; however, it is not known what phytochemicals promote contaminant degradation. One monocot and two dicotyledon plants were grown in PAH-contaminated soil from a manufactured gas plant (MGP) site. A phytotoxicity assay confirmed greater soil decontamination in rhizospheres when compared to bulk soil controls. Bacteria were isolated from plant roots (rhizobacteria) and selected for growth on anthracene and chrysene on PAH-amended plates. Rhizosphere isolates metabolized 3- and 4-ring PAHs and PAH catabolic intermediates in liquid incubations. Aromatic root exudate compounds, namely flavonoids and simple phenols, were also substrates for isolated rhizobacteria. In particular, the phenolic compounds-morin, caffeic acid, and protocatechuic acid-appear to be linked to bacterial degradation of 3- and 4-ring PAHs in the rhizosphere.

  17. Formation of nitro-PAHs from the heterogeneous reaction of ambient particle-bound PAHs with NO3/N2O5

    Science.gov (United States)

    Zimmermann, K.; Jariyasopit, N.; Simonich, S. L.; Atkinson, R.; Arey, J.

    2012-12-01

    Polycyclic aromatic hydrocarbons (PAHs) and their nitrated derivatives (nitro-PAHs) have been shown to be mutagenic in bacterial and mammalian assays and are classified as probable human carcinogens. Semi-volatile PAHs partition between the gas and particulate phases, depending on their liquid-phase vapor pressures and ambient temperatures. These PAHs have been extensively measured in ambient particulate matter and can ultimately undergo long-range transport from source regions (e.g., China to the western USA) (1). During transport these particle-bound PAHs may undergo reaction with NO3/N2O5 to form nitro-PAH derivatives. Previous studies of heterogeneous nitration of PAHs have used particles composed of graphite, diesel soot, and wood smoke (2-4). This study investigates the heterogeneous formation of nitro-PAHs from ambient particle-bound PAHs from Beijing, China and sites located within the Los Angeles air basin. These ambient particle samples, along with filters coated with isotopically labeled PAHs, were exposed to a mix of NO2/NO3/N2O5 in a 7000 L Teflon chamber, with analysis focused on the heterogeneous formation of molecular weight 247 and 273 nitro-PAHs. The heterogeneous formation of certain nitro-PAHs (including1-nitropyrene and 1- and 2-nitrotriphenylene) was observed for some, but not all, ambient samples. Formation of nitro-PAHs typically formed through gas-phase reactions (2-nitrofluoranthene and 2-nitropyrene) was not observed. The effect of particle age and local photochemical conditions during sampling on the degree of nitration in environmental chamber reactions, as well as ambient implications, will be presented. 1. Primbs, T.; Simonich, S.; Schmedding, D.; Wilson, G.; Jaffe, D.; Takami, A.; Kato, S.; Hatakeyama, S.; Kajii, Y. Environ. Sci. Technol. 2007, 41, 3551-3558. 2. Esteve, W.; Budzinski, H.; Villenave, E. Atmospheric Environment 2004, 38, 6063-6072. 3. Nguyen, M.; Bedjanian, Y.; Guilloteau, A. Journal of Atmospheric Chemistry 2009, 62

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

    Science.gov (United States)

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

    2001-11-12

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

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

    Directory of Open Access Journals (Sweden)

    Juan Zhang

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

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

    Science.gov (United States)

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

    2011-03-01

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

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

    Science.gov (United States)

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

    2015-04-01

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

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

    OpenAIRE

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

    2013-01-01

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

  3. Relationship between polycyclic aromatic hydrocarbons (PAHs) and particle size in dated core sediments in Lake Lianhuan, Northeast China

    International Nuclear Information System (INIS)

    Sun, Li; Zang, Shuying

    2013-01-01

    Atmospheric particle associated with pyrogenic polycyclic aromatic hydrocarbons (PAHs) poses serious threats to human health by inhalation exposure, especially in semiarid areas. Hence, the distributions of PAHs and particle size in two core sediments collected from Lake Lianhuan, Northeast China were studied. The sediments were dated radiometrically, and particle size distribution and PAH concentration were evaluated and potential human health risk was assessed. From 1980 to 2007, the dominant PAHs in the two cores were 2- and 3-ring PAHs, and the concentrations of 3–6 ring PAHs gradually increased from the early 1990s. Diagnostic ratios indicated that pyrogenic PAHs were the main sources of PAHs which changed over time from combustions of wood and coal to liquid fossil fuel sources. Fine particles ( 125 μm were found. Future research should focus on the seven carcinogenic pyrogenic PAHs due to a rapidly increasing trend since 1995 based on the assessment of toxic equivalency factors. - Highlights: • PAHs and particle size in core sediments were used to evaluate the role of eolian particles in delivering pyrogenic PAHs. • Changes of PAH sources closely followed local historical socioeconomic development since 1980s. • Changes of particulate sources from eolian to lacustrine reflected the evolving history of the lake. • Significant correlations between pyrogenic PAHs and eolian particles indicated potential risk from inhalation exposure. • Petroleum source PAHs are likely to stick to coarse particles and accumulate in lake sediments by surface runoff

  4. Dissipation of polycyclic aromatic hydrocarbons (PAHs) in the rhizosphere: Synthesis through meta-analysis

    International Nuclear Information System (INIS)

    Ma Bin; He Yan; Chen Huaihai; Xu Jianming; Rengel, Zed

    2010-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are widespread and persistent organic pollutants with high carcinogenic effect and toxicity; their behavior and fate in the soil-plant system have been widely investigated. In the present paper, meta-analysis was used to explore the interaction between plant growth and dissipation of PAHs in soil based on the large body of published literature. Plants have a promoting effect on PAH dissipation in soils. There was no difference in PAH dissipation between soils contaminated with single and mixed PAHs. However, plants had a more obvious effect on PAH dissipation in freshly-spiked soils than in long-term field-polluted soils. Additionally, a positive effect of the number of microbial populations capable of degrading PAHs was observed in the rhizosphere compared with the bulk soil. Our meta-analysis established the importance of the rhizosphere effect on PAH dissipation in variety of the soil-plant systems. - The meta-analysis provides the first quantitative evidence of the positive effect of rhizosphere processes on PAH dissipation.

  5. Effects of profession on urinary PAH metabolite levels in the US population.

    Science.gov (United States)

    Liu, Bian; Jia, Chunrong

    2016-01-01

    Although exposure to polycyclic aromatic hydrocarbons (PAHs) is common in both environmental and occupational settings, few studies have compared PAH exposure among people with different professions. The purpose of this study was to investigate the variations in recent PAH exposure among different occupational groups over time using national representative samples. The study population consisted of 4162 participants from the 2001 to 2008 National Health and Nutrition Examination Survey, who had both urinary PAH metabolites and occupational information. Four corresponding monohydroxy-PAH urine metabolites: naphthalene (NAP), fluorene (FLUO), phenanthrene (PHEN), and pyrene (PYR) among seven broad occupational groups were analyzed using weighted linear regression models, adjusting for creatinine levels, sociodemographic factors, smoking status, and sampling season. The overall geometric mean concentrations of NAP, FLUO, PHEN, and PYR were 6927, 477, 335, and 87 ng/L, respectively. All four PAH metabolites were elevated in the "extractive, construction, and repair (ECR)" group, with 21-42 % higher concentrations than those in the reference group of "management." Similar trends were seen in the "operators, fabricators, and laborers (OFL)" group for FLUO, PHEN, and PYR. In addition, both "service" and "support" groups had elevated FLUO. Significant (p PAH exposure. Heterogeneous distributions of urinary PAH metabolites among people with different job categories exist at the population level. The upward temporal trends in NAP and PYR warrant reduction in PAH exposure, especially among those with OFL and ECR occupations.

  6. Impact of soil organic matter on the distribution of polycyclic aromatic hydrocarbons (PAHs) in soils

    International Nuclear Information System (INIS)

    Yang, Y.; Zhang, N.; Xue, M.; Tao, S.

    2010-01-01

    The knowledge on the distribution of hydrophobic organic contaminants in soils can provide better understanding for their fate in the environment. In the present study, the n-butanol extraction and humic fractionation were applied to investigate the impact of SOM on the distribution of polycyclic aromatic hydrocarbons (PAHs). The results indicated that 80.5%-94.8% of the target PAHs could be extracted by n-butanol and 63.1%-94.6% of PAHs were associated with fulvic acid (FA). Concentrations of un-extracted PAHs increased significantly with the increasing soil organic matter (SOM), however, such an association was absent for the extractable fractions. The results suggested that the sequestration played a critical role in the accumulation of PAHs in soils. SOM also retarded the diffusion of PAHs into the humin fractions. It implied that sequestration in SOM was critical for PAH distribution in soils, while the properties of PAH compounds also had great influences. - Soil organic matter played an important role in the distribution of PAHs in soils through sequestration.

  7. Molecular and stable carbon isotopic characterization of PAH contaminants at McMurdo Station, Antarctica

    International Nuclear Information System (INIS)

    Kim, Moonkoo . E-mail moonkoo.kim@wmich.edu; Kennicutt, Mahlon C.; Qian Yaorong

    2006-01-01

    The molecular and stable carbon isotopic compositions of contaminant polycyclic aromatic hydrocarbons (PAHs) at McMurdo Station, Antarctica were analyzed in samples collected from land and sub-tidal area. PAHs in the study areas were characterized by high amounts of naphthalene and alkylated naphthalenes from petroleum products introduced by human activities in the area. Principal component analysis (PCA) of PAH composition data identified multiple sources of PAH contamination in the study area. Compositional assignments of origins were confirmed using compound specific stable carbon isotopic analysis

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

    Science.gov (United States)

    Balcıoğlu, Esra Billur

    2016-08-15

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

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

    Science.gov (United States)

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

    2010-01-01

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

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

    Science.gov (United States)

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

    2012-06-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-11-15

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

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

    Science.gov (United States)

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

    2011-11-01

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

  13. Comparing PAH availability from manufactured gas plant soils and sediments with chemical and biological tests. 1. PAH release during water desorption and supercritical carbon dioxide extraction

    Energy Technology Data Exchange (ETDEWEB)

    Hawthorne, S.B.; Poppendieck, D.G.; Grabanski, C.B.; Loehr, R.C. [University of North Dakota, Grand Forks, ND (US). Energy and Environmental Research Center

    2002-11-15

    Soil and sediment samples from OG (oil gas) and CG (coal gas) manufactured gas plant (MGP) sites in the United States that had been closed for about 50 years were selected to represent a range of PAH concentrations and sample matrix compositions. Samples varied from vegetated soils to lampblack soot and had carbon contents from 3 to 87 wt%. Supercritical carbon dioxide, SFE desorption and water/XAD{sub 2} desorption curves were determined and fit with a simple two-site model to determine the rapid-released fraction (F) for PAHs ranging from naphthalene to benzo-(ghi)perylene. F values varied greatly among the samples. Release rates did not correlate with sample matrix characteristics including PAH concentrations, elemental composition or 'hard' and 'soft' organic carbon, indicating that PAH release cannot easily be estimated on the basis of sample matrix composition. F values for CG site samples obtained with SFE and water desorption agreed well but SFE yielded higher F values for the OG samples. These behaviors were attributed to the stronger ability of carbon dioxide than water to desorb PAHs from the highly aromatic (hard) carbon of the OG matrixes, while carbon dioxide and water showed similar abilities to desorb PAHs from the more polar (soft) carbon of the CG samples. The combined SFE and water desorption approaches should improve the understanding of PAH sequestration and release from contaminated soils and sediments and provide the basis for subsequent studies, using the same samples to compare PAH release with PAH availability to earthworms. 46 refs., 4 figs., 4 tabs.

  14. PAH (Polycyclic Aromatic Hydrocarbon) bioaccumulation and PAHs/shell weight index in Ruditapes philippinarum (Adams & Reeve, 1850) from the Vallona lagoon (northern Adriatic Sea, NE Italy).

    Science.gov (United States)

    Cacciatore, Federica; Bernarello, Valentina; Boscolo Brusà, Rossella; Sesta, Giulio; Franceschini, Gianluca; Maggi, Chiara; Gabellini, Massimo; Lamberti, Clauda Virno

    2018-02-01

    The Vallona lagoon is a transitional area located in the Po River delta (NE, ITALY) traditionally exploited for Manila clam (Ruditapes philippinarum) farming. During 2007-2008, a pipeline was buried in the middle of the lagoon to connect an off-shore structure to facilities on land. PAH levels were monitored in Manila clams and sediments before, during and after the pipeline construction to assess the impact of the activities through the pattern of distribution of the PAH compounds. PAH bioaccumulation in clams displayed seasonal fluctuations with higher levels in autumnal and wintry surveys than in spring-summer. Principal component analysis applied to PAHs in clams highlighted a petrogenic input during ante operam period and a pyrolytic origin during the burying activities. On the contrary, sediment PAH concentrations resulted quite similar both among sites and periods. Biota-Sediment-Accumulation-Factor values also confirmed that sediments were not the major source of PAH pollution for clams in this study. The welfare of clams was examined through two physiological indices (condition index and survival in air) to check the effects of the activities on a commercial resource. Both physiological indices exhibited seasonal variations connected to natural endogenous and exogenous factors; however survival in air was the most sensitive index in highlighting the effects of the pipeline burying activities. Finally, to ensure that PAH bioavailability assessment was not affected by seasonal variation of soft tissues of molluscs, PAHs/shell weight index was applied. Higher levels of this index were observed before and during the burying activities, whilst, after that, values significantly lowered. Moreover, the normalization enabled us to highlight the PAH uptake from clams in some particular periods and to compare different populations in a long-term biomonitoring program with data obtained from different periods of the year. Copyright © 2017 Elsevier Inc. All rights

  15. Effect of Warfarin Treatment on Survival of Patients With Pulmonary Arterial Hypertension (PAH) in the Registry to Evaluate Early and Long-Term PAH Disease Management (REVEAL).

    Science.gov (United States)

    Preston, Ioana R; Roberts, Kari E; Miller, Dave P; Sen, Ginny P; Selej, Mona; Benton, Wade W; Hill, Nicholas S; Farber, Harrison W

    2015-12-22

    Long-term anticoagulation is recommended in idiopathic pulmonary arterial hypertension (IPAH). In contrast, limited data support anticoagulation in pulmonary arterial hypertension (PAH) associated with systemic sclerosis (SSc-PAH). We assessed the effect of warfarin anticoagulation on survival in IPAH and SSc-PAH patients enrolled in Registry to Evaluate Early and Long-term PAH Disease Management (REVEAL), a longitudinal registry of group I PAH. Patients who initiated warfarin on study (n=187) were matched 1:1 with patients never on warfarin, by enrollment site, etiology, and diagnosis status. Descriptive analyses were conducted to compare warfarin users and nonusers by etiology. Survival analyses with and without risk adjustment were performed from the time of warfarin initiation or a corresponding quarterly update in matched pairs to avoid immortal time bias. Time-varying covariate models were used as sensitivity analyses. Mean warfarin treatment was 1 year; mean international normalized ratios were 1.9 (IPAH) and 2.0 (SSc-PAH). Two-thirds of patients initiating warfarin discontinued treatment before the last study assessment. There was no survival difference with warfarin in IPAH patients (adjusted hazard ratio, 1.37; P=0.21) or in SSc-PAH patients (adjusted hazard ratio, 1.60; P=0.15) in comparison with matched controls. However, SSc-PAH patients receiving warfarin within the previous year (hazard ratio, 1.57; P=0.031) or any time postbaseline (hazard ratio, 1.49; P=0.046) had increased mortality in comparison with warfarin-naïve patients. No significant survival advantage was observed in IPAH patients who started warfarin. In SSc-PAH patients, long-term warfarin was associated with poorer survival than in patients not receiving warfarin, even after adjusting for confounders. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00370214. © 2015 The Authors.

  16. Mixtures Estimation and Applications

    CERN Document Server

    Mengersen, Kerrie; Titterington, Mike

    2011-01-01

    This book uses the EM (expectation maximization) algorithm to simultaneously estimate the missing data and unknown parameter(s) associated with a data set. The parameters describe the component distributions of the mixture; the distributions may be continuous or discrete. The editors provide a complete account of the applications, mathematical structure and statistical analysis of finite mixture distributions along with MCMC computational methods, together with a range of detailed discussions covering the applications of the methods and features chapters from the leading experts on the subject

  17. Molecular epidemiology studies of carcinogenic environmental pollutants. Effects of polycyclic aromatic hydrocarbons (PAHs) in environmental pollution on exogenous and oxidative DNA damage.

    Science.gov (United States)

    Farmer, Peter B; Singh, Rajinder; Kaur, Balvinder; Sram, Radim J; Binkova, Blanka; Kalina, Ivan; Popov, Todor A; Garte, Seymour; Taioli, Emanuela; Gabelova, Alena; Cebulska-Wasilewska, Antonina

    2003-11-01

    Exposure to high levels of environmental air pollution is known to be associated with an increased carcinogenic risk. The individual contribution to this risk derived from specific carcinogenic chemicals within the complex mixture of air pollution is less certain, but may be explored by the use of molecular epidemiological techniques. Measurements of biomarkers of exposure, of effect and of susceptibility provide information of potential benefit for epidemiological and cancer risk assessment. The application of such techniques has been mostly concerned in the past with the carcinogenic polycyclic aromatic hydrocarbons (c-PAHs) that are associated with particulate matter in air pollution, and has showed clear evidence of genotoxic effects, such as DNA adducts, chromosome aberrations (CA) and ras oncogene overexpression, in environmentally exposed Czech and Polish populations. We are currently extending these studies by an investigation of populations exposed to environmental pollution in three European countries, Czech Republic, Slovak Republic and Bulgaria. This pays particular attention to PAHs, but also investigates the extent of radically induced (oxidative) DNA damage in the exposed populations. Policemen, bus drivers and controls, who carried personal monitors to determine their exposures to PAHs have been studied, and blood and urine were collected. Antioxidant and dietary status were assessed in these populations. Stationary monitors were also used for ambient air monitoring. Amongst the parameters studied in the biological samples were: (a) exposure biomarkers, such as PAH adducts with DNA, p53 and p21(WAF1) protein levels, (b) oxidative DNA damage, (c) the biological effect of the exposure by measurement of chromosome damage by fluorescence in situ hybridisation (FISH) or conventional methods, and (d) polymorphisms in carcinogen metabolising and DNA repair enzymes. Repair ability was also measured by the Comet assay. In vitro systems are being evaluated to

  18. Pristine Arctic: Background mapping of PAHs, PAH metabolites and inorganic trace elements in the North-Atlantic Arctic and sub-Arctic coastal environment

    Energy Technology Data Exchange (ETDEWEB)

    Jörundsdóttir, Hrönn Ólína, E-mail: hronn.o.jorundsdottir@matis.is [Matis Ltd., Icelandic Food and Biotech R and D, Vinlandsleid 12, 113 Reykjavik (Iceland); Jensen, Sophie [Matis Ltd., Icelandic Food and Biotech R and D, Vinlandsleid 12, 113 Reykjavik (Iceland); Hylland, Ketil; Holth, Tor Fredrik [Department of Biosciences, University of Oslo, P.O. Box 1066 Blindern, N-0316 Oslo (Norway); Gunnlaugsdóttir, Helga [Matis Ltd., Icelandic Food and Biotech R and D, Vinlandsleid 12, 113 Reykjavik (Iceland); Svavarsson, Jörundur [University of Iceland, Department of Life and Environmental Sciences, Askja - Natural Science Building, Sturlugata 7, 101 Reykjavík (Iceland); Ólafsdóttir, Ásdís [The University of Iceland´s Research Centre in Sudurnes, Gardvegi 1, 245 Sandgerdi (Iceland); El-Taliawy, Haitham [Matis Ltd., Icelandic Food and Biotech R and D, Vinlandsleid 12, 113 Reykjavik (Iceland); Rigét, Frank; Strand, Jakob [Department of Bioscience, Arctic Research Centre, Aarhus University, Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde (Denmark); Nyberg, Elisabeth; Bignert, Anders [Swedish Museum of Natural History, P.O. Box 50007, 104 05 Stockholm (Sweden); Hoydal, Katrin S. [The Faroese Environment Agency, Traðagøta 38, P.O. Box 2048, FO-165 Argir, the Faroe Islands (Faroe Islands); Halldórsson, Halldór Pálmar [The University of Iceland´s Research Centre in Sudurnes, Gardvegi 1, 245 Sandgerdi (Iceland)

    2014-09-15

    As the ice cap of the Arctic diminishes due to global warming, the polar sailing route will be open larger parts of the year. These changes are likely to increase the pollution load on the pristine Arctic due to large vessel traffic from specific contaminant groups, such as polycyclic aromatic hydrocarbons (PAHs). A well-documented baseline for PAH concentrations in the biota in the remote regions of the Nordic Seas and the sub-Arctic is currently limited, but will be vital in order to assess future changes in PAH contamination in the region. Blue mussels (Mytilus edulis) were collected from remote sites in Greenland, Iceland, the Faroe Islands, Norway and Sweden as well as from urban sites in the same countries for comparison. Cod (Gadus morhua) was caught north of Iceland and along the Norwegian coast. Sixteen priority PAH congeners and the inorganic trace elements arsenic, cadmium, mercury and lead were analysed in the blue mussel samples as well as PAH metabolites in cod bile. Σ{sub 16}PAHs ranged from 28 ng/g dry weight (d.w.) (Álftafjörður, NW Iceland) to 480 ng/g d.w. (Ísafjörður, NW Iceland). Mussel samples from Mjóifjörður, East Iceland and Maarmorilik, West Greenland, contained elevated levels of Σ{sub 16}PAHs, 370 and 280 ng/g d.w., respectively. Levels of inorganic trace elements varied with highest levels of arsenic in mussels from Ísafjörður, Iceland (79 ng/g d.w.), cadmium in mussels from Mjóifjörður, Iceland (4.3 ng/g d.w.), mercury in mussels from Sørenfjorden, Norway (0.23 ng/g d.w.) and lead in mussels from Maarmorilik, Greenland (21 ng/g d.w.). 1-OH-pyrene was only found above limits of quantification (0.5 ng/mL) in samples from the Norwegian coast, ranging between 44 and 140 ng/ml bile. Generally, PAH levels were low in mussels from the remote sites investigated in the study, which indicates limited current effect on the environment. - Highlights: • Low levels of PAHs in blue mussels from remote areas of the Arctic. • Low

  19. Microbial degradation of polycyclic aromatic hydrocarbons (PAHs). Pt. 1

    International Nuclear Information System (INIS)

    Eichler, B.; Bryniok, D.; Vorbeck, C.; Lutz, M.; Ackermann, B.; Freier-Schroeder, D.; Knackmuss, H.J.

    1992-01-01

    Productive degradation of the higher molecular PAHs benz(a)anthracene (four rings), benzo(a)pyrene and benzo(k)fluoranthene (five rings) through pure bacterial cultures is demonstrated in this paper for the first time. Consequently, a degradation potential for lower and higher molecular polycyclic aromatics up to five rings exists both in the ground of the fromer coking site and in the ground of the former gas works of Stuttgart. Further samples from contaminated soils, coking waste water and sediments showed similar results. This suggests that the bacterial flora present in the soil itself can be successfully used to clean up contaminated ground. (orig.) [de

  20. UV action spectroscopy of protonated PAH derivatives. Methyl substituted quinolines

    DEFF Research Database (Denmark)

    Klærke, Benedikte; Holm, Anne; Andersen, Lars Henrik

    2011-01-01

    using the electrostatic storage ring ELISA, an electrospray ion source and 3 ns UV laser pulses. Results. It is shown that the absorption profile is both redshifted and broadened when moving the methyl group from the heterocycle containing nitrogen to the homoatomic ring. The absorption profiles......Aims. We investigate the production of molecular photofragments upon UV excitation of PAH derivatives, relevant for the interstellar medium. Methods. The action absorption spectra of protonated gas-phase methyl-substituted quinolines (CH3−C9H7NH+) have been recorded in the 215–338 nm spectral range...

  1. The determination of polycyclic aromatic hydrocarbons in human urine by high-resolution gas chromatography-mass spectrometry.

    Science.gov (United States)

    Cho, Sung-Hee; Lee, Sun-Kyung; Kim, Chong Hyeak

    2018-05-01

    Polycyclic aromatic hydrocarbons (PAHs), organic compounds formed by at least two condensed aromatic rings, are ubiquitous environmental pollutants that are produced by incomplete combustion of organic materials. PAHs have been classified as carcinogenIC to humans by the International Agency for Research on Cancer, because they can bind to DNA, causing mutations. Therefore, the levels of PAHs in human urine can be used as an indicator for potential carcinogenesis and cell mutation. An analytical method was developed for the accurate measurement of PAHs in urine using high-resolution gas chromatography-mass spectrometry. Urine samples were extracted by an Oasis HLB extraction cartridge after enzymatic hydrolysis with a β-glucuronidase/arylsulfatase cocktail. The 18 PAHs were separated using an Agilent DB-5 MS capillary column (30 m × 0.25 mm, 0.25 μm) and monitored by time-of-flight mass spectrometry. Under the optimized method, the linearity of calibration curves was >0.994. The limits of detection at a signal-to-noise ratio of 3 were 10-100 ng/L. The coefficients of variation were in the range of 0.4-9.0%. The present method was highly accurate for simultaneous determination of 18 PAHs in human urine and could be applied to monitoring and biomedical investigations to check exposure of PAHs. Copyright © 2017 John Wiley & Sons, Ltd.

  2. I-optimal mixture designs

    OpenAIRE

    GOOS, Peter; JONES, Bradley; SYAFITRI, Utami

    2013-01-01

    In mixture experiments, the factors under study are proportions of the ingredients of a mixture. The special nature of the factors in a mixture experiment necessitates specific types of regression models, and specific types of experimental designs. Although mixture experiments usually are intended to predict the response(s) for all possible formulations of the mixture and to identify optimal proportions for each of the ingredients, little research has been done concerning their I-optimal desi...

  3. Mixtures and interactions

    NARCIS (Netherlands)

    Groten, J.P.

    2000-01-01

    Drinking water can be considered as a complex mixture that consists of tens, hundreds or thousands of chemicals of which the composition is qualitatively and quantitatively not fully known. From a public health point of view it is most relevant to answer the question of whether chemicals in drinking

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

    Science.gov (United States)

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

    2006-02-15

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

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

    Science.gov (United States)

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

    2017-10-14

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

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

    International Nuclear Information System (INIS)

    Bourgeault, A.; Gourlay-Francé, C.

    2013-01-01

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

  7. Effect of a cationic surfactant on the volatilization of PAHs from soil.

    Science.gov (United States)

    Lu, Li; Zhu, Lizhong

    2012-06-01

    Cationic surfactants are common in soils because of their use in daily cosmetic and cleaning products, and their use as a soil amendment for the mitigation and remediation of organic contaminated soils has been proposed. Such surfactant may affect the transfer and fate of organic contaminants in the environment. This study investigated the effect of a cationic surfactant, dodecylpyridinium bromide (DDPB), on the volatilization of polycyclic aromatic hydrocarbons (PAHs) from a paddy soil. The volatilization of PAHs from moist soil amended with different concentrations of DDPB was tested in an open system. The specific effects of DDPB on the liquid-vapor and solid-vapor equilibriums of PAHs were separately investigated in closed systems by headspace analysis. DDPB affects both liquid-vapor and solid-vapor processes of PAHs in soil. At DDPB concentrations below the critical micelle concentration (CMC), movement of PAHs from the bulk solution to the gas-liquid interface appeared to be facilitated by interaction between PAHs and the surfactant monomers adsorbed at the gas-liquid interface, promoting the volatilization of PAHs from solution. However, when DDPB was greater than the CMC, volatilization was inhibited due to the solubilization of PAHs by micelles. On the other hand, the formation of sorbed surfactant significantly inhibited the solid-vapor volatilization of PAHs. The overall effect of the two simultaneous effects of DDPB on liquid-vapor and solid-vapor processes was a decreased volatilization loss of PAHs from soil. Inhibition of PAH volatilization was more significant for the soil with a lower moisture content.

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

    Directory of Open Access Journals (Sweden)

    Jian Ye

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-06-01

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

  10. Atmospheric versus biological sources of polycyclic aromatic hydrocarbons (PAHs) in a tropical rain forest environment

    International Nuclear Information System (INIS)

    Krauss, Martin; Wilcke, Wolfgang; Martius, Christopher; Bandeira, Adelmar G.; Garcia, Marcos V.B.; Amelung, Wulf

    2005-01-01

    To distinguish between pyrogenic and biological sources of PAHs in a tropical rain forest near Manaus, Brazil, we determined the concentrations of 21 PAHs in leaves, bark, twigs, and stem wood of forest trees, dead wood, mineral topsoil, litter layer, air, and Nasutitermes termite nest compartments. Naphthalene (NAPH) was the most abundant PAH with concentrations of 35 ng m -3 in air (>85% of the Σ21PAHs concentration), up to 1000 μg kg -1 in plants (>90%), 477 μg kg -1 in litter (>90%), 32 μg kg -1 in topsoil (>90%), and 160 μg kg -1 (>55%) in termite nests. In plants, the concentrations of PAHs in general decreased in the order leaves > bark > twigs > stem wood. The concentrations of most low-molecular weight PAHs in leaves and bark were near equilibrium with air, but those of NAPH were up to 50 times higher. Thus, the atmosphere seemed to be the major source of all PAHs in plants except for NAPH. Additionally, phenanthrene (PHEN) had elevated concentrations in bark and twigs of Vismia cayennensis trees (12-60 μg kg -1 ), which might have produced PHEN. In the mineral soil, perylene (PERY) was more abundant than in the litter layer, probably because of in situ biological production. Nasutitermes nests had the highest concentrations of most PAHs in exterior compartments (on average 8 and 15 μg kg -1 compared to -1 in interior parts) and high PERY concentrations in all compartments (12-86 μg kg -1 ), indicating an in situ production of PERY in the nests. Our results demonstrate that the deposition of pyrolytic PAHs from the atmosphere controls the concentrations of most PAHs. However, the occurrence of NAPH, PHEN, and PERY in plants, termite nests, and soils at elevated concentrations supports the assumption of their biological origin. - Evidence of non-pyrolytic, biogenic production of PAHs is provided

  11. Photochemistry of PAHs in cosmic water ice. The effect of concentration on UV-VIS spectroscopy and ionization efficiency

    Science.gov (United States)

    Cuylle, Steven H.; Allamandola, Louis J.; Linnartz, Harold

    2014-02-01

    Context. Observations and models show that polycyclic aromatic hydrocarbons (PAHs) are ubiquitous in the interstellar medium. Like other molecules in dense clouds, PAHs accrete onto interstellar dust grains, where they are embedded in an ice matrix dominated by water. In the laboratory, mixed molecular ices (not containing PAHs) have been extensively studied using Fourier transform infrared absorption spectroscopy. Experiments including PAHs in ices have started, however, the concentrations used are typically much higher than the concentrations expected for interstellar ices. Optical spectroscopy offers a sensitive alternative. Aims: We report an experimental study of the effect PAH concentration has on the electronic spectra and the vacuum UV (VUV) driven processes of PAHs in water-rich ices. The goal is to apply the outcome to cosmic ices. Methods: Optical spectroscopic studies allow us to obtain in-situ and quasi real-time electronic solid state spectra of two prototypical PAHs (pyrene and coronene) embedded in water ice under VUV photoprocessing. The study is carried out on PAH:H2O concentrations in the range of 1:30 000 to pure PAH, covering the temperature range from 12 to 125 K. Results: PAH concentration strongly influences the efficiency of PAH cation formation. At low concentrations, ionization efficiencies are over 60% dropping to about 15% at 1:1000. Increasing the PAH concentration reveals spectral broadening in neutral and cation PAH spectra attributed to PAH clustering inside the ice. At the PAH concentrations expected for interstellar ices, some 10 to 20% may be present as cations. The presence of PAHs in neutral and ion form will add distinctive absorption bands to cosmic ice optical spectra and this may serve as a tool to determine PAH concentrations.

  12. Enhanced bioremediation of PAH-contaminated soil by immobilized bacteria with plant residue and biochar as carriers

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Baoliang; Yuan, Miaoxin; Qian, Linbo [Zhejiang Univ., Hangzhou (China). Dept. of Environmental Science; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou (China)

    2012-10-15

    Polycyclic aromatic hydrocarbons (PAHs) are largely accumulated in soils in China. The immobilized-microorganism technique (IMT) is a potential approach for abating soil contamination with PAHs. However, few studies about the application of IMT to contaminated soil remediation were reported. Due to recalcitrance to decomposition, biochar application to soil may enhance soil carbon sequestration, but few studies on the application of biochars to remediation of contaminated soil were reported. In this study, we illustrated enhanced bioremediation of soil having a long history of PAH contamination by IMT using plant residues and biochars as carriers. Two PAH-degrading bacteria, Pseudomonas putida and an unidentified indigenous bacterium, were selected for IMT. The extractability and biodegradation of 15 PAHs in solution and an actual PAH-contaminated soil amended with immobilized-bacteria materials were investigated under different incubation periods. The effects of carriers and the molecular weight of PAHs on bioremediation efficiency were determined to illustrate their different bio-dissipation mechanisms of PAHs in soil. The IMT can considerably enhance the removal of PAHs. Carriers impose different effects on PAH bio-dissipation by amended soil with immobilized-bacteria, which can directly degrade the carrier-associated PAHs. The removal of PAHs from soil depended on PAH molecular weight and carrier types. Enhanced bio-dissipation by IMT was much stronger for 4- and 5-ring PAHs than for 3- and 6-ring ones in soil. Only P400 biochar-immobilized bacteria enhanced bio-dissipation of all PAHs in contaminated soil after a 90-day incubation. Biochar can promote bioremediation of contaminated soil as microbial carriers of IMT. It is vital to select an appropriate biochar as an immobilized carrier to stimulate biodegradation. It is feasible to use adsorption carriers with high sorptive capabilities to concentrate PAHs as well as microorganisms and thereby enhance

  13. Supplementary measurements for air monitoring under NOVANA - Benzene and PAH; Supplerende maalinger til luftovervaagning under NOVANA - benzen og PAH

    Energy Technology Data Exchange (ETDEWEB)

    Ellermann, T.; Klenoe Noejgaard, J.; Bossi, R.

    2011-10-15

    The report presents results from a project carried out for the Danish Environmental Protection Agency. The aim of the project was to carry out several measuring campaigns in order to be able to better assess the monitoring needs for PAH and benzene in relation to EU's air quality directives. The results show that the mean concentrations of benzene are almost at the same level in Denmark's four largest cities, and that the concentrations are both below the threshold value (5mug/m3) as well as below the lower assessment threshold (2mug/m3). The report presents a method for objectively estimation the benzene concentration based on measurements of CO. The method can be applied to fulfil the monitoring need for benzene in those zones where no measurements of benzene are made. Measurements of PAH, especially benzo(a)pyrene, have been made during 12 months in the period 2010-2011 in an area with many wood burning furnaces are used (the town Jyllinge). The concentrations of benzo(a)pyrene in Jyllinge is almost three times higher than in the street H.C. Andersens Boulevard in Copenhagen. The concentrations of benzo(a)pyrene in Jylllinge are 0,6 ng/m3, which corresponds to the upper assessment threshold (0,6 ng/m3) and is 40% below the measuring value (1 ng/m3). On this basis, there is a need for re-evaluating the monitoring of PAH in the sub-programme for air under NOVANA. Measurements of PM{sub 10} showed that the levels in the towns Jyllinge, Lille Valby/Risoe and at the H.C. Oersted Institute in Copenhagen are all at about 20-22 mug/m3. (LN)

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

    International Nuclear Information System (INIS)

    Lehndorff, E.; Schwark, L.

    2009-01-01

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

  15. PAH clearance after renal ischemia and reperfusion is a function of impaired expression of basolateral Oat1 and Oat3.

    Science.gov (United States)

    Bischoff, Ariane; Bucher, Michael; Gekle, Michael; Sauvant, Christoph

    2014-02-01

    Determination of renal plasma flow (RPF) by para-aminohippurate (PAH) clearance leads to gross underestimation of this respective parameter due to impaired renal extraction of PAH after renal ischemia and reperfusion injury. However, no mechanistic explanation for this phenomenon is available. Based on our own previous studies we hypothesized that this may be due to impairment of expression of the basolateral rate limiting organic anion transporters Oat1 and Oat3. Thus, we investigated this phenomenon in a rat model of renal ischemia and reperfusion by determining PAH clearance, PAH extraction, PAH net secretion, and the expression of rOat1 and rOat3. PAH extraction was seriously impaired after ischemia and reperfusion which led to a threefold underestimation of RPF when PAH extraction ratio was not considered. PAH extraction directly correlated with the expression of basolateral Oat1 and Oat3. Tubular PAH secretion directly correlated with PAH extraction. Consequently, our data offer an explanation for impaired renal PAH extraction by reduced expression of the rate limiting basolateral organic anion transporters Oat1 and Oat3. Moreover, we show that determination of PAH net secretion is suitable to correct PAH clearance for impaired extraction after ischemia and reperfusion in order to get valid results for RPF.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-04-15

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

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

    Science.gov (United States)

    Zhang, Xincheng; Wang, Weiyu; Zhu, Xianlei

    2017-04-01

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

  18. Natural organic matter to enhance electrokinetic transport of PAH

    Energy Technology Data Exchange (ETDEWEB)

    Suer, P.; Joensson, S.; Allard, B. [Man-Technology-Environment Research Centre, Oerebro Univ. (Sweden)

    2001-07-01

    The remediation of contaminated soil can be enhanced with natural organic matter (NOM) as a complexing agent for pollutants. NOM has both hydrophobic and acidic properties, so that it is charged and thus subject to electroremediation. At the same time many contaminants have a high affinity for organic matter. Organic matter was produced in situ in an electric field or added in solute form. The resulting dissolved organic matter was transported towards the cathode, probably by cationic colloids. Produced dissolved organic matter included high molecular weight molecules near the cathode, at the site of pH buffering. Pyrene and phenanthrene were likewise transported towards the cathode. Movement was small but distinctive in 2-day experiments. Clay influence the soil/water distribution of the PAH but no effect on the total transport could be discerned. The presence of solid organic matter in the soil removed all PAH from the water phase, even though the concentration of organic matter in the water phase was high as well. (orig.)

  19. Development of the Pulmonary Arterial Hypertension-Symptoms and Impact (PAH-SYMPACT®) questionnaire: a new patient-reported outcome instrument for PAH.

    Science.gov (United States)

    McCollister, Deborah; Shaffer, Shannon; Badesch, David B; Filusch, Arthur; Hunsche, Elke; Schüler, René; Wiklund, Ingela; Peacock, Andrew

    2016-06-14

    Regulators and clinical experts increasingly recognize the importance of incorporating patient-reported outcomes (PROs) in clinical studies of therapies for pulmonary arterial hypertension (PAH). No PAH-specific instruments have been developed to date in accordance with the 2009 FDA guidance for the development of PROs as endpoints in clinical trials. A qualitative research study was conducted to develop a new instrument assessing PAH symptoms and their impacts following the FDA PRO guidance. A cross-sectional study was conducted at 5 centers in the US in symptomatic PAH patients aged 18-80 years. Concept elicitation was based on 5 focus group discussions, after which saturation of emergent concepts was reached. A PRO instrument for PAH symptoms and their impacts was drafted. To assess the appropriateness of items, instructions, response options, and recall periods, 2 rounds of one-on-one cognitive interviews were conducted, with instrument revisions following each round. Additional interviews tested the usability of an electronic version (ePRO). PRO development considered input from an international Steering Committee, and translatability and lexibility assessments. Focus groups comprised 25 patients (5 per group); 20 additional patients participated in cognitive interviews (10 per round); and 10 participated in usability interviews. Participants had a mean ± SD age of 53.1 ± 15.8 years, were predominantly female (93 %), and were diverse in race/ethnicity, WHO functional class (FC I/II: 56 %, III/IV: 44 %), and PAH etiology (idiopathic: 56 %, familial: 2 %, associated: 42 %). The draft PRO instrument (PAH-SYMPACT®) was found to be clear, comprehensive, and relevant to PAH patients in cognitive interviews. Items were organized in a draft conceptual framework with 16 symptom items in 4 domains (respiratory symptoms, tiredness, cardiovascular symptoms, other symptoms) and 25 impact items in 5 domains (physical activities, daily activities, social

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2001-02-01

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

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

    Science.gov (United States)

    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.

  2. 1-Hydroxypyrene as a biomarker of PAH exposure in the marine polychaete Nereis diversicolor

    DEFF Research Database (Denmark)

    Tairova, Zhanna; Giessing, Anders; Hansen, Rikke

    2009-01-01

    The possibility of using the pyrene metabolite I-hydroxypyrene as a biomarker of polycyclic aromatic hydrocarbons (PAHs) exposure was investigated by exposure of the marine polychaete Nereis diversicolor to several PAHs in the laboratory. Animals were exposed to pyrene alone and to five different...

  3. Remediation technologies for treatment of PAH contaminated soil and strategies to enhance process efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, J.; Alcantara, M. T.; Pazos, M.; Longo, M. A.; Sanroman, M. A.

    2009-07-01

    The presence of carcinogenic polycyclic aromatic hydrocarbons (PAHs) in soils poses a potential threat to human health. The removal of these contaminants presents a challenge to scientists and engineers. PAHs are characterized by their palpable hydrophobic nature. Consequently, these species tend to be adsorbed on solid particulates, especially on the organic fraction of the solids. (Author)

  4. Remediation technologies for treatment of PAH contaminated soil and strategies to enhance process efficiency

    International Nuclear Information System (INIS)

    Gomez, J.; Alcantara, M. T.; Pazos, M.; Longo, M. A.; Sanroman, M. A.

    2009-01-01

    The presence of carcinogenic polycyclic aromatic hydrocarbons (PAHs) in soils poses a potential threat to human health. The removal of these contaminants presents a challenge to scientists and engineers. PAHs are characterized by their palpable hydrophobic nature. Consequently, these species tend to be adsorbed on solid particulates, especially on the organic fraction of the solids. (Author)

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

    Science.gov (United States)

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

    2014-06-15

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

  6. Occurrence of Nitro-PAH in the Atmosphere in a Rural Area

    DEFF Research Database (Denmark)

    Nielsen, Tom; Seitz, B.; Ramdahl, T.

    1984-01-01

    -(a)pyrene have been identied in samples of airborne particulate matter. Furthermore, 8-nitrofluoranthene has been tentatively identified. The amounts of mononitro-PAH are one to two orders of magnitude lower than the most common carcinogenic PAH, as e.g. benzo(a)pyrene. Filter effects have been studied, 9...

  7. A directional passive air sampler for monitoring polycyclic aromatic hydrocarbons (PAHs) in air mass

    International Nuclear Information System (INIS)

    Tao, S.; Liu, Y.N.; Lang, C.; Wang, W.T.; Yuan, H.S.; Zhang, D.Y.; Qiu, W.X.; Liu, J.M.; Liu, Z.G.; Liu, S.Z.; Yi, R.; Ji, M.; Liu, X.X.

    2008-01-01

    A passive air sampler was developed for collecting polycyclic aromatic hydrocarbons (PAHs) in air mass from various directions. The airflow velocity within the sampler was assessed for its responses to ambient wind speed and direction. The sampler was examined for trapped particles, evaluated quantitatively for influence of airflow velocity and temperature on PAH uptake, examined for PAH uptake kinetics, calibrated against active sampling, and finally tested in the field. The airflow volume passing the sampler was linearly proportional to ambient wind speed and sensitive to wind direction. The uptake rate for an individual PAH was a function of airflow velocity, temperature and the octanol-air partitioning coefficient of the PAH. For all PAHs with more than two rings, the passive sampler operated in a linear uptake phase for three weeks. Different PAH concentrations were obtained in air masses from different directions in the field test. - A novel directional passive air sampler was developed and tested for monitoring PAHs in air masses from different directions

  8. MANAGEMENT OF PAH-IMPACTED SITES VIA IN SITU CHEMICAL CONTAINMENT AND MONITORING

    Science.gov (United States)

    On a world-wide basis the magnitude of environmental contamination problems involving polycyclic aromatic hydrocarbon (PAHs) is unmatched by any other group of organic chemicals. Despite the recognized limitations to PAH biodegradation (e.g., intrinsic chemical stability of the h...

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

    Science.gov (United States)

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

    2015-02-01

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

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

    Science.gov (United States)

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

    2015-10-01

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

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

    Science.gov (United States)

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

    2010-01-01

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

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

    Science.gov (United States)

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

    2014-02-01

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

  13. Polycyclic Aromatic Hydrocarbons (PAH) in Danish Smoked Fish and Meat Products

    DEFF Research Database (Denmark)

    Duedahl-Olesen, Lene; White, S.; Binderup, Mona-Lise

    2006-01-01

    Twenty seven PAH were detected in 45 selected smoked food samples produced in Denmark, including mackerel, herring, trout, small sausages, salami, and bacon. The sum of PAH in smoked meat products ranged from 24 mu g/kg for salami to 64 mu g/kg in bacon, while those in fish products ranged from 2...

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

    DEFF Research Database (Denmark)

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

    2016-01-01

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

  15. FATE OF PAH COMPOUNDS IN TWO SOIL TYPES: INFLUENCE OF VOLATILIZATION, ABIOTIC LOSS, AND BIOLOGICAL ACTIVITY

    Science.gov (United States)

    The fate of 14 polycyclic aromatic hydrocarbon (PAH) compounds was evaluated with regard to interphase transfer potential and mechanisms of treatment in soil under unsaturated conditions. Volatilization and abiotic and biotic fate of the PAHs were determined using two soils not p...

  16. Health implications of PAH release from coated cast iron drinking water distribution systems in The Netherlands.

    Science.gov (United States)

    Blokker, E J Mirjam; van de Ven, Bianca M; de Jongh, Cindy M; Slaats, P G G Nellie

    2013-05-01

    Coal tar and bitumen have been historically used to coat the insides of cast iron drinking water mains. Polycyclic aromatic hydrocarbons (PAHs) may leach from these coatings into the drinking water and form a potential health risk for humans. We estimated the potential human cancer risk from PAHs in coated cast iron water mains. In a Dutch nationwide study, we collected drinking water samples at 120 locations over a period of 17 days under various operational conditions, such as undisturbed operation, during flushing of pipes, and after a mains repair, and analyzed these samples for PAHs. We then estimated the health risk associated with an exposure scenario over a lifetime. During flushing, PAH levels frequently exceeded drinking water quality standards; after flushing, these levels dropped rapidly. After the repair of cast iron water mains, PAH levels exceeded the drinking water standards for up to 40 days in some locations. The estimated margin of exposure for PAH exposure through drinking water was > 10,000 for all 120 measurement locations, which suggests that PAH exposure through drinking water is of low concern for consumer health. However, factors that differ among water systems, such as the use of chlorination for disinfection, may influence PAH levels in other locations.

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

    Directory of Open Access Journals (Sweden)

    Peng-hui Li

    2015-01-01

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

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

    Science.gov (United States)

    Karaca, Gizem; Tasdemir, Yucel

    2013-01-01

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

  19. Soot modeling of counterflow diffusion flames of ethylene-based binary mixture fuels

    KAUST Repository

    Wang, Yu

    2015-03-01

    A soot model was developed based on the recently proposed PAH growth mechanism for C1-C4 gaseous fuels (KAUST PAH Mechanism 2, KM2) that included molecular growth up to coronene (A7) to simulate soot formation in counterflow diffusion flames of ethylene and its binary mixtures with methane, ethane and propane based on the method of moments. The soot model has 36 soot nucleation reactions from 8 PAH molecules including pyrene and larger PAHs. Soot surface growth reactions were based on a modified hydrogen-abstraction-acetylene-addition (HACA) mechanism in which CH3, C3H3 and C2H radicals were included in the hydrogen abstraction reactions in addition to H atoms. PAH condensation on soot particles was also considered. The experimentally measured profiles of soot volume fraction, number density, and particle size were well captured by the model for the baseline case of ethylene along with the cases involving mixtures of fuels. The simulation results, which were in qualitative agreement with the experimental data in the effects of binary fuel mixing on the sooting structures of the measured flames, showed in particular that 5% addition of propane (ethane) led to an increase in the soot volume fraction of the ethylene flame by 32% (6%), despite the fact that propane and ethane are less sooting fuels than is ethylene, which is in reasonable agreement with experiments of 37% (14%). The model revealed that with 5% addition of methane, there was an increase of 6% in the soot volume fraction. The average soot particle sizes were only minimally influenced while the soot number densities were increased by the fuel mixing. Further analysis of the numerical data indicated that the chemical cross-linking effect between ethylene and the dopant fuels resulted in an increase in PAH formation, which led to higher soot nucleation rates and therefore higher soot number densities. On the other hand, the rates of soot surface growth per unit surface area through the HACA mechanism were

  20. Effect of pyrolysis temperatures on freely dissolved polycyclic aromatic hydrocarbon (PAH) concentrations in sewage sludge-derived biochars.

    Science.gov (United States)

    Zielińska, Anna; Oleszczuk, Patryk

    2016-06-01

    The aim of this study was to evaluate the effect of sewage sludge pyrolysis on freely dissolved (Cfree) polycyclic aromatic hydrocarbon (PAH) contents in biochars. Four sewage sludges with varying properties and PAH contents were pyrolysed at temperatures of 500 °C, 600 °C or 700 °C. Cfree PAH contents were determined using polyoxymethylene (POM). The contents of Cfree PAHs in the sludges ranged from 262 to 294 ng L(-1). Sewage sludge-derived biochars have from 2.3- to 3.4-times lower Cfree PAH contents comparing to corresponding sewage sludges. The Cfree PAH contents in the biochars ranged between 81 ng L(-1) and 126 ng L(-1). As regards agricultural use of biochar, the lower contents of Cfree PAHs in the biochars compared to the sewage sludges makes biochar a safer material than sewage sludge in terms of PAH contents. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Bioremediation mechanisms of combined pollution of PAHs and heavy metals by bacteria and fungi: A mini review.

    Science.gov (United States)

    Liu, Shao-Heng; Zeng, Guang-Ming; Niu, Qiu-Ya; Liu, Yang; Zhou, Lu; Jiang, Lu-Hua; Tan, Xiao-Fei; Xu, Piao; Zhang, Chen; Cheng, Min

    2017-01-01

    In recent years, knowledge in regard to bioremediation of combined pollution of polycyclic aromatic hydrocarbons (PAHs) and heavy metals by bacteria and fungi has been widely developed. This paper reviews the species of bacteria and fungi which can tackle with various types of PAHs and heavy metals entering into environment simultaneously or successively. Microbial activity, pollutants bioavailability and environmental factors (e.g. pH, temperature, low molecular weight organic acids and humic acids) can all affect the bioremediation of PAHs and heavy metals. Moreover, this paper summarizes the remediation mechanisms of PAHs and heavy metals by microbes via elucidating the interaction mechanisms of heavy metals with heavy metals, PAHs/PAHs metabolites with PAHs and PAHs with heavy metals. Based on the above reviews, this paper also discusses the potential research needs for this field. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

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

    2012-01-01

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

  3. Current state of knowledge in microbial degradation of polycyclic aromatic hydrocarbons (PAHs: a review

    Directory of Open Access Journals (Sweden)

    Debajyoti Ghosal

    2016-08-01

    Full Text Available Polycyclic aromatic hydrocarbons (PAHs include a group of organic priority pollutants of critical environmental and public health concern due to their toxic, genotoxic, mutagenic and/or carcinogenic properties and their ubiquitous occurrence as well as recalcitrance. The increased awareness of their various adverse effects on ecosystem and human health has led to a dramatic increase in research aimed towards removing PAHs from the environment. PAHs may undergo adsorption, volatilization, photolysis, and chemical oxidation, although transformation by microorganisms is the major neutralization process of PAH-contaminated sites in an ecologically accepted manner. Microbial degradation of PAHs depends on various environmental conditions, such as nutrients, number and kind of the microorganisms, nature as well as chemical property of the PAH being degraded. A wide variety of bacterial, fungal and algal species have the potential to degrade/transform PAHs, among which bacteria and fungi mediated degradation has been studied most extensively. In last few decades microbial community analysis, biochemical pathway for PAHs degradation, gene organization, enzyme system, genetic regulation for PAH degradation have been explored in great detail. Although, xenobiotic-degrading microorganisms have incredible potential to restore contaminated environments inexpensively yet effectively, but new advancements are required to make such microbes effective and more powerful in removing those compounds, which were once thought to be recalcitrant. Recent analytical chemistry and genetic engineering tools might help to improve the efficiency of degradation of PAHs by microorganisms, and minimize uncertainties of successful bioremediation. However, appropriate implementation of the potential of naturally occurring microorganisms for field bioremediation could be considerably enhanced by optimizing certain factors such as bioavailability, adsorption and mass transfer of

  4. Impact of electrochemical treatment of soil washing solution on PAH degradation efficiency and soil respirometry

    International Nuclear Information System (INIS)

    Mousset, Emmanuel; Huguenot, David; Hullebusch, Eric D. van; Oturan, Nihal; Guibaud, Gilles; Esposito, Giovanni; Oturan, Mehmet A.

    2016-01-01

    The remediation of a genuinely PAH-contaminated soil was performed, for the first time, through a new and complete investigation, including PAH extraction followed by advanced oxidation treatment of the washing solution and its recirculation, and an analysis of the impact of the PAH extraction on soil respirometry. The study has been performed on the remediation of genuine PAH-contaminated soil, in the following three steps: (i) PAH extraction with soil washing (SW) techniques, (ii) PAH degradation with an electro-Fenton (EF) process, and (iii) recirculation of the partially oxidized effluent for another SW cycle. The following criteria were monitored during the successive washing cycles: PAH extraction efficiency, PAH oxidation rates and yields, extracting agent recovery, soil microbial activity, and pH of soil. Two representative extracting agents were compared: hydroxypropyl-beta-cyclodextrin (HPCD) and a non-ionic surfactant, Tween"® 80. Six PAH with different numbers of rings were monitored: acenaphthene (ACE), phenanthrene (PHE), fluoranthene (FLA), pyrene (PYR), benzo(a)pyrene (BaP), and benzo(g,h,i)perylene (BghiP). Tween"® 80 showed much better PAH extraction efficiency (after several SW cycles) than HPCD, regardless of the number of washing cycles. Based on successive SW experiments, a new mathematical relation taking into account the soil/water partition coefficient (Kd*) was established, and could predict the amount of each PAH extracted by the surfactant with a good correlation with experimental results (R"2 > 0.975). More HPCD was recovered (89%) than Tween"® 80 (79%), while the monitored pollutants were completely degraded (>99%) after 4 h and 8 h, respectively. Even after being washed with partially oxidized solutions, the Tween"® 80 solutions extracted significantly more PAH than HPCD and promoted better soil microbial activity, with higher oxygen consumption rates. Moreover, neither the oxidation by-products nor the acidic media (p

  5. Current State of Knowledge in Microbial Degradation of Polycyclic Aromatic Hydrocarbons (PAHs): A Review

    Science.gov (United States)

    Ghosal, Debajyoti; Ghosh, Shreya; Dutta, Tapan K.; Ahn, Youngho

    2016-01-01

    Polycyclic aromatic hydrocarbons (PAHs) include a group of organic priority pollutants of critical environmental and public health concern due to their toxic, genotoxic, mutagenic and/or carcinogenic properties and their ubiquitous occurrence as well as recalcitrance. The increased awareness of their various adverse effects on ecosystem and human health has led to a dramatic increase in research aimed toward removing PAHs from the environment. PAHs may undergo adsorption, volatilization, photolysis, and chemical oxidation, although transformation by microorganisms is the major neutralization process of PAH-contaminated sites in an ecologically accepted manner. Microbial degradation of PAHs depends on various environmental conditions, such as nutrients, number and kind of the microorganisms, nature as well as chemical property of the PAH being degraded. A wide variety of bacterial, fungal and algal species have the potential to degrade/transform PAHs, among which bacteria and fungi mediated degradation has been studied most extensively. In last few decades microbial community analysis, biochemical pathway for PAHs degradation, gene organization, enzyme system, genetic regulation for PAH degradation have been explored in great detail. Although, xenobiotic-degrading microorganisms have incredible potential to restore contaminated environments inexpensively yet effectively, but new advancements are required to make such microbes effective and more powerful in removing those compounds, which were once thought to be recalcitrant. Recent analytical chemistry and genetic engineering tools might help to improve the efficiency of degradation of PAHs by microorganisms, and minimize uncertainties of successful bioremediation. However, appropriate implementation of the potential of naturally occurring microorganisms for field bioremediation could be considerably enhanced by optimizing certain factors such as bioavailability, adsorption and mass transfer of PAHs. The main

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

    Science.gov (United States)

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

    2016-04-01

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

  7. APPLICATION OF FENTON’S REAGENT ON REMEDIATION OF POLYCYCLIC AROMATIC HYDROCARBONs (PAHs IN SPIKED SOIL

    Directory of Open Access Journals (Sweden)

    Nursiah La Nafie

    2010-06-01

    Full Text Available Problem associated with Polycyclic Aromatic Hydrocarbons (PAHs contaminated site in environmental media have received increasing attention. To resolve such problems, innovative in situ methods are urgently required. This work investigated the feasibility of using Fenton's Reagent to remediate PAHs in spiked soil. PAHs were spiked into soil to simulate contaminated soil. Fenton's Reagent (H2O2 + Fe2+ and surfactant were very efficient in destruction of PAHs including naphthalene, anthracene, fluoranthene, pyrene, and benzo(apyrene from spiked soil. It was indicated by the fact that more than 96% of PAHs were degraded in the solution and the spiked soil.   Keywords: Environmental, Fenton's Reagent, Polycyclic Aromatic Hydrocarbons, and Spiked soil.

  8. Assessing PAH removal from clayey soil by means of electro-osmosis and electrodialysis

    DEFF Research Database (Denmark)

    Lima, Ana T.; Ottosen, Lisbeth M.; Heister, Katja

    2012-01-01

    Polycyclic aromatic hydrocarbons (PAH) are persistent and toxic contaminants which are difficult to remove from fine porous material like clayey soils. The present work aims at studying two electroremediation techniques for the removal of PAHs from a spiked natural silt soil from Saudi Arabia...... and a silty loam soil from The Netherlands which has been exposed to tar contamination for over 100years. The two techniques at focus are electro-osmosis and electrodialysis. The latter is applied for the first time for the removal of PAH. The efficiency of the techniques is studied using these two soils......, having been subjected to different PAH contact times.Two surfactants were used: the non-ionic surfactant Tween 80 and anionic surfactant sodium dodecyl sulphate (SDS) to aid desorption of PAHs from the soil. Results show a large discrepancy in the removal rates between spiked soil and long-term field...

  9. PAH Metabolites in Bile of European Eel (Anguilla anguilla) from Morocco.

    Science.gov (United States)

    Wariaghli, Fatima; Kammann, Ulrike; Hanel, Reinhold; Yahyaoui, Ahmed

    2015-12-01

    Environmental pollution of fish with organic contaminants is a topic of rising attention in Morocco. Polycyclic aromatic hydrocarbons (PAH) are prominent organic contaminants which are rapidly metabolized in fish. Their metabolites are accumulated in the bile fluid and can be used to assess PAH exposure. The two PAH metabolites 1-hydroxypyrene and 1-hydroxyphenanthrene were quantified in European eels (Anguilla anguilla) from two Moroccan river systems by high-performance liquid chromatography with fluorescence detection. Mean values ranged from 52 to 210 ng/mL 1-hydroxypyrene and from 61 to 73 ng/mL 1-hydroxyphenanthrene. The overall concentrations of PAH metabolites in eel from Morocco appeared moderate compared to eel from European rivers and coastal sites. The present study provides first information on concentrations of PAH metabolites in fish from Morocco.

  10. Review of the quantification techniques for polycyclic aromatic hydrocarbons (PAHs) in food products.

    Science.gov (United States)

    Bansal, Vasudha; Kumar, Pawan; Kwon, Eilhann E; Kim, Ki-Hyun

    2017-10-13

    There is a growing need for accurate detection of trace-level PAHs in food products due to the numerous detrimental effects caused by their contamination (e.g., toxicity, carcinogenicity, and teratogenicity). This review aims to discuss the up-to-date knowledge on the measurement techniques available for PAHs contained in food or its related products. This article aims to provide a comprehensive outline on the measurement techniques of PAHs in food to help reduce their deleterious impacts on human health based on the accurate quantification. The main part of this review is dedicated to the opportunities and practical options for the treatment of various food samples and for accurate quantification of PAHs contained in those samples. Basic information regarding all available analytical measurement techniques for PAHs in food samples is also evaluated with respect to their performance in terms of quality assurance.

  11. Mixture based outlier filtration

    Czech Academy of Sciences Publication Activity Database

    Pecherková, Pavla; Nagy, Ivan

    2006-01-01

    Roč. 46, č. 2 (2006), s. 30-35 ISSN 1210-2709 R&D Projects: GA MŠk 1M0572; GA MDS 1F43A/003/120 Institutional research plan: CEZ:AV0Z10750506 Keywords : data filtration * system modelling * mixture models Subject RIV: BD - Theory of Information http://library.utia.cas.cz/prace/20060165.pdf

  12. Analysis of a Pareto Mixture Distribution for Maritime Surveillance Radar

    Directory of Open Access Journals (Sweden)

    Graham V. Weinberg

    2012-01-01

    Full Text Available The Pareto distribution has been shown to be an excellent model for X-band high-resolution maritime surveillance radar clutter returns. Given the success of mixture distributions in radar, it is thus of interest to consider the effect of Pareto mixture models. This paper introduces a formulation of a Pareto intensity mixture distribution and investigates coherent multilook radar detector performance using this new clutter model. Clutter parameter estimates are derived from data sets produced by the Defence Science and Technology Organisation's Ingara maritime surveillance radar.

  13. Evidences for balancing selection from PAH-BglII and PAH-EcoRI polymorphisms in Isfahan population

    Directory of Open Access Journals (Sweden)

    Zahra Fazeli Attar

    2010-01-01

    Full Text Available Two polymorphic markers including BglII and EcoRI, were identified at intron 1 and intron 5 of PAH gene. In order to test whether these polymorphisms are behaving as neutral alleles or are being subjected to selective pressures in Isfahan population, 110 individuals were genotyped by PCR-RFLP. The Arlequin input file was prepared by use of phase-known haplotype data and Neutrality tests (Tajima D test and Fu’s Fs test were done using Arlequin program. 42 individuals were found heterozygous for both polymorphisms whose haplotype phase remained unknown. The BglII-EcoRI haplotype phase was known only at 68 individuals who were used for preparation of input file. Tajima's D value and Fs value at Isfahan population were 1.7 and 1.02, respectively. Positive values of Fs and D>0 indicated that these polymorphisms are under selection pressure at Isfahan population. Although these polymorphisms were in the non-coding region of PAH gene, but these were not neutral alleles and positive values of these tests provided evidence for balancing selection of these polymorphisms at Isfahan population. The results of this study could improve our understanding of evolutionary history and structure of Isfahan population.

  14. Monitoring of polycyclic aromatic hydrocarbons (PAH) in food supplements containing botanicals and other ingredients on the Dutch market.

    Science.gov (United States)

    Martena, M J; Grutters, M M P; De Groot, H N; Konings, E J M; Rietjens, I M C M

    2011-01-01

    Food supplements can contain polycyclic aromatic hydrocarbons (PAH). The European Food Safety Authority (EFSA) has defined 16 priority PAH that are both genotoxic and carcinogenic and identified eight priority PAH (PAH8) or four of these (PAH4) as good indicators of the toxicity and occurrence of PAH in food. The current study aimed to determine benzo[a]pyrene and other EFSA priority PAH in different categories of food supplements containing botanicals and other ingredients. From 2003 to 2008, benzo[a]pyrene exceeded the limit of quantification (LOQ) in 553 (44%) of 1258 supplements with a lower-bound mean of 3.37 µg kg(-1). In 2008 and 2009, benzo[a]pyrene and 12 other EFSA priority PAH were determined in 333 food supplements. Benzo[a]pyrene exceeded the LOQ in 210 (63%) food supplements with a lower-bound mean of 5.26 µg kg(-1). Lower-bound mean levels for PAH4 and PAH8(-indeno[1,2,3-cd]pyrene) were 33.5 and 40.5 µg kg(-1), respectively. Supplements containing resveratrol, Ginkgo biloba, St. John's wort and propolis showed relatively high PAH4 levels in 2008 and 2009. Before 2008, supplements with these ingredients and also dong quai, green tea or valerian contained relatively high benzo[a]pyrene levels. On average, PAH4 intake resulting from food supplement use will be at the lower end of the range of contributions of main food groups to PAH4 exposure, although individual food supplements can contribute significantly to PAH4 exposure. Regular control of EFSA indicator PAH levels in food supplements may prove a way forward to reduce further the intake of PAH from food.

  15. Resolution propositions

    International Nuclear Information System (INIS)

    2003-05-01

    To put a resolution to the meeting in relation with the use of weapons made of depleted uranium is the purpose of this text. The situation of the use of depleted uranium by France during the Gulf war and other recent conflicts will be established. This resolution will give the most strict recommendations face to the eventual sanitary and environmental risks in the use of these kind of weapons. (N.C.)

  16. Vertical distributions of PAHs in the sediments of four lakes in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Fukushima, Takehiko; Watanabe, Seigo; Kamiya, Koichi [Tsukuba Univ., Ibaraki (Japan). Graduate School of Life and Environment; Ozaki, Noriatsu [Hiroshima Univ., Higashihiroshima (Japan). Graduate School of Engineering

    2012-12-15

    Purpose: The purpose of this study was to elucidate historical trends, spatial variations, and the sources of polycyclic aromatic hydrocarbons (PAHs) pollution in several Japanese lakes. Materials and methods: The vertical distributions of PAHs in the core samples of sediments taken at several points in lakes Kasumigaura, Suwa, Kizaki, and Shinji were determined using a gas chromatograph equipped with a mass selective detector and combined with chronological information and the physical/elemental properties of the sediment. Results and discussion: Seventeen related compounds (congeners) typically had concentration peaks at sediment depths corresponding to the 1960s to 1970s. In Lake Shinji and one bay of Lake Kasumigaura, there was a tendency for PAH concentrations to increase downstream; in contrast, another bay of Lake Kasumigaura showed the reverse trend. During big flood events, the fluxes of PAHs increased due to large inputs of particulate matter, although PAH concentrations were reduced. For the four study lakes and other similar lakes, PAH concentrations of surface sediments were approximately proportional to population densities in the respective watersheds, while the total input of PAHs to the lakes were correlated with their population and watershed area. The source apportionment analysis using isomer ratios for the congener profiles indicated that the principal sources of the PAHs in the lake sediments were gasoline and/or diesel engine exhausts and biomass burning. Conclusions: The observed concentration peaks showed a deterioration of the chemical quality of atmospheric conditions around 1960-1970 and a recent tendency for their amelioration. Between-lake differences suggest that the influence of human activity in the watersheds influences sediment PAH concentrations. The PAH sources were identified to be of pyrogenic origin. (orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-12-20

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

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

    Science.gov (United States)

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

    2017-06-01

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

  19. Analytical Evaluation to Determine Selected PAHs in a Contaminated Soil With Type II Fuel; Metodo Optimizado de Extraccion por Ultrasonidos para la Determinacion de PAHs Seleccionados en un Suelo Contaminado con Fuel de Tipo II

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Alonso, S.; Perez Pastor, R. M.; Sevillano Castano, M. L.; Garcia Frutos, F. J.

    2010-10-21

    A study on the optimization of an ultrasonic extraction method for selected PAHs determination in soil contaminated by type II fuel and by using HPLC with fluorescence detector is presented. The main objective was optimize the analytical procedure, minimizing the volume of solvent and analysis time and avoiding possible loss by evaporation. This work was carried out as part of a project that investigated a remediation process of agricultural land affected by an accidental spillage of fuel (Plan Nacional I + D + i, CTM2007-64 537). The paper is structured as: Optimization of wavelengths in the chromatographic conditions to improve resolution in the analysis of fuel samples. Optimization of the main parameters affecting in the extraction process by sonication. Comparison of results with those obtained by accelerated solvent extraction. (Author) 3 refs.

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

    NARCIS (Netherlands)

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

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

  1. Deciphering the roles of Arabidopsis LPCAT and PAH in phosphatidylcholine homeostasis and pathway coordination for chloroplast lipid synthesis.

    Science.gov (United States)

    Wang, Liping; Kazachkov, Michael; Shen, Wenyun; Bai, Mei; Wu, Hong; Zou, Jitao

    2014-12-01

    Phosphatidylcholine (PC) is a key intermediate in the metabolic network of glycerolipid biosynthesis. Lysophosphatidylcholine acyltransferase (LPCAT) and phosphatidic acid phosphatase (PAH) are two key enzymes of PC homeostasis. We report that LPCAT activity is markedly induced in the Arabidopsis pah mutant. The quadruple pah lpcat mutant, with dual defects in PAH and LPCAT, had a level of lysophosphatidylcholine (LPC) that was much higher than that in the lpcat mutants and a PC content that was higher than that in the pah mutant. Comparative molecular profile analysis of monogalactosyldiacylglycerol and digalactosyldiacylglycerol revealed that both the pah and pah lpcat mutants had increased proportions of 34:6 from the prokaryotic pathway despite differing levels of LPCAT activity. We show that a decreased representation of the C16:0 C18:2 diacylglycerol moiety in PC was a shared feature of pah and pah lpcat, and that this change in PC metabolic profile correlated with the increased prokaryotic contribution to chloroplast lipid synthesis. We detected increased PC deacylation in the pah lpcat mutant that was attributable at least in part to the induced phospholipases. Increased LPC generation was also evident in the pah mutant, but the phospholipases were not induced, raising the possibility that PC deacylation is mediated by the reverse reaction of LPCAT. We discuss possible roles of LPCAT and PAH in PC turnover that impacts lipid pathway coordination for chloroplast lipid synthesis. © 2014 National Research Council Canada. The Plant Journal © 2014 Society For Experimental Biology and John Wiley & Sons.

  2. A method to simultaneously determining the reduction in PAH dissolved concentrations and bioaccessibility in carbon amended soils

    DEFF Research Database (Denmark)

    Marchal, Geoffrey; Smith, Kilian E. C.; Rein, Arno

    In order to investigate the potential of different soil amendments (activated charcoal (AC), charcoal (biochar), compost) to sorb PAHs and their effect on bioaccessibility and biodegradation of PAHs in soil, a method was developed that can determine simultaneously the changes in PAH dissolved...

  3. Mixture for plugging absorption zones

    Energy Technology Data Exchange (ETDEWEB)

    Sitinkov, G V; Kovalenko, N G; Makarov, L V; Zinnatulchin, Ts Kh

    1981-01-17

    A mixture is proposed for plugging absorption zones. The mixture contains synthetic polymer and a solvent. So as to increase the penetrability of the mixture through a reduction in its viscosity and an increase in insulation properties, the compound contains either Capron or Neilon as the synthetic polyamide resin polmyer, and concentrated chloride as the solvent. The mixture is prepared in a special AzINMASh-30 unit (acid cart). After the mixture has been produced, it is injected into the borehole by means of an acid cart pump. So as to prevent coaggulation at the point when the mixture in injected into the stratum through tubes, the mixture is placed betwen chemically inert fluids, for example, a clay mortar. The inert and compressed fluids are injected by means of a cementing unit. The entire process of production and application of the mixture is simple and fully automated through the use of well-known equipment.

  4. Separating Underdetermined Convolutive Speech Mixtures

    DEFF Research Database (Denmark)

    Pedersen, Michael Syskind; Wang, DeLiang; Larsen, Jan

    2006-01-01

    a method for underdetermined blind source separation of convolutive mixtures. The proposed framework is applicable for separation of instantaneous as well as convolutive speech mixtures. It is possible to iteratively extract each speech signal from the mixture by combining blind source separation...

  5. Mixtures of truncated basis functions

    DEFF Research Database (Denmark)

    Langseth, Helge; Nielsen, Thomas Dyhre; Rumí, Rafael

    2012-01-01

    In this paper we propose a framework, called mixtures of truncated basis functions (MoTBFs), for representing general hybrid Bayesian networks. The proposed framework generalizes both the mixture of truncated exponentials (MTEs) framework and the mixture of polynomials (MoPs) framework. Similar t...

  6. Removal of Heavy Metals and PAH in Highway Detention Ponds

    DEFF Research Database (Denmark)

    Bentzen, Thomas Ruby; Larsen, Torben; Thorndahl, Søren Liedtke

    2005-01-01

    , which has been designed according to standard design criteria for several decades. The study will focus on heavy metals (Cd, Cr, Cu, Pb and Zn) and polyaromatic hydrocarbons (PAH). The long-term simulation of input of flow and pollution to the ponds will be a hind cast based on time series of historical......The paper presents some of the first results from a study of the removal of pollutants in highway detention ponds in Denmark. The objective of the study is to set up a procedure for long-term modelling of discharges of pollutants to the environment from the many Danish highway detention ponds...... rainfalls. The modelling will take place in a special version of the MIKE URBAN. The modelling is calibrated and validated on measurements from selected highway catchments. The removal of pollutants in the ponds is studied by local measurements in combination with CFD modelling using the MIKE 21 and MIKE 3...

  7. Remediation of PAH-contaminated soil using Achromobacter sp

    International Nuclear Information System (INIS)

    Cutright, T.J.; Lee, S.

    1994-01-01

    Several technologies have the potential to effectively remediate soil contaminated with polycyclic aromatic hydrocarbons (PAHs): solvent extraction, coal-oil agloflotation, supercritical extraction, and bioremediation. Due to the cost effectiveness and in-situ treatment capabilities of bioremediation, studies were conducted to determine the efficiency of Achromobacter sp. to remediate an industrial contaminated soil sample. Specifically, the use of three different mineral salt solutions in conjunction with the Achromobacter sp. was investigated. The molecular identification of the contaminants and their respective levels after remediation were determined using a Hewlett-Packard 1050 HPLC. Preliminary results show a 92% remediation for the use of two of the mineral salt solutions after 20 days' treatment. After 8 weeks, the remediation efficiency reached 99%. Bioremediation was also critically compared to the other potential remediation technologies

  8. Accumulation of policyclic aromatic hydrocarbons (PAHs) in surface litter and soils in four forests in the United States

    Science.gov (United States)

    Obrist, D.; Perlinger, J. A.; Zielinska, B.

    2014-12-01

    Polycyclic aromatic hydrocarbons (PAHs) are toxic environmental pollutants originating from the incomplete combustion of organic material, both from natural or anthropogenic sources. Once emitted, they can be transported across thousands of kilometers impacting remote environments. Here, we characterize the distribution of 23 PAHs and 9 oxygenated PAHs (Σ32PAH) in litter and soils in four remote forests in the United States. Concentrations of Σ32PAH in fresh surface litter (Oi layers) showed very low levels in three of the four forests (mixed coniferous forest in Maine, deciduous blue oak forest in California, and a coniferous forest in Washington State), with PAHs levels much lower than those reported in previous studies from Europe. The analysis showed that PAHs represented a mix of regional background sources. Highest PAH levels were observed in a coniferous forest floor in Florida, attributable to frequent prescribed burning of understory vegetation at this site, and supported by high contributions of retene (>7%; compared to atmospheric deposition. Within mineral soils, Σ32PAH:OC ratios increased with depth (Ah horizons: 750±198 ng g-1; B horizons: 1,202±97 ng g-1), indicating that vertical transfer in mineral soils leads to significant accumulation of PAH in subsoils. ΣPAH:OC increases observed in deeper soil layers may be attributed to slower mineralization rates of PAHs compared to OC, plus vertical transport as indicated by preferential enrichment of PAHs with low Kow (i.e., more water-soluble PAHs). Finally, percentage of potentially biologically produced PAH (Σ Naph+Phen+Pery) were low and consistent across the litter/soil horizons, suggesting that biological production is minor or absent at our sites.

  9. Polycyclic aromatic hydrocarbons (PAHs), their transfer into and dislocation within soil; Eintraege von polyzyklischen aromatischen Kohlenwasserstoffen (PAH) und ihre Verlagerung im Boden

    Energy Technology Data Exchange (ETDEWEB)

    Duerbeck, H W; Niehaus, R; Mueller, U; Bueker, I [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Angewandte Physikalische Chemie

    1998-12-31

    In order to assess the terrestrial hazard potential of polycyclic aromatic hydrocarbons (PAHs), it is vital to investigate their nuisance concentrations and deposition to soil and plants as well as their dislocation in soil. This was the object of the first part of the research programme ``Locational evaluation of chemical soil pollution``, conducted by the national research institutions. It was headed ``Analysis of exposure`` and comprised the following individual contributions: 1. Integrated long-term measurements of polycyclic aromatic hydrocarbons in soil air at ground level (FZJ), 2. Determination of PAH nuisance concentrations at the Scheyern experimental station as well as at the motorway by-passing Munich to the east (A 99), near Kirchheim (GSF), 3. Investigations regarding PAH exposure via the air pathway and inclusion of acquired data in substance flows made up for the east-German dry zone (Bad Lauchstaedt), (UFZ), 4. Simulation of PAH concentration and deposition in south-western Germany (FZK). (orig./SR) [Deutsch] Zur Abschaetzung des Gefaehrdungspotentials von Polycyclischen Aromatischen Kohlenwasserstoffen (PAK) im terrestrischen Bereich sind daher Untersuchungen ueber die Immissionskonzentrationen und die Deposition auf Boeden und Pflanzen sowie ueber ihre Verlagerung im Boden von essentieller Bedeutung. Die Bearbeitung dieser Thematik erfolgte im Teilbereich I `Eintragsanalyse` des AGF-Programms `Standortgerechte Bewertung chemischer Bodenbelastungen` mit folgenden Einzelbeitraegen: 1. Integrierende Langzeitmessung von Polycyclischen Aromatischen Kohlenwasserstoffen in bodennaher Luft, (FZJ) 2. Bestimmung der PAH-Immissionskonzentrationen am Versuchsgut Scheyern sowie an der oestlichen Autobahnumgehung von Muenchen (A 99) bei Kirchheim, (GSF) 3. Untersuchungen zum Eintrag von PAH ueber den Luftpfad und Einbeziehung der Daten in Stoffkreislaeufe im Mitteldeutschen Trockengebiet (Bad Lauchstaedt), (UFZ) 4. Simulation der PAH-Konzentration und

  10. Response of PAH-degrading genes to PAH bioavailability in the overlying water, suspended sediment, and deposited sediment of the Yangtze River.

    Science.gov (United States)

    Xia, Xinghui; Xia, Na; Lai, Yunjia; Dong, Jianwei; Zhao, Pujun; Zhu, Baotong; Li, Zhihuang; Ye, Wan; Yuan, Yue; Huang, Junxiong

    2015-06-01

    The degrading genes of hydrophobic organic compounds (HOCs) serve as indicators of in situ HOC degradation potential, and the existing forms and bioavailability of HOCs might influence the distribution of HOC-degrading genes in natural waters. However, little research has been conducted to study the relationship between them. In the present study, nahAc and nidA genes, which act as biomarkers for naphthalene- and pyrene-degrading bacteria, were selected as model genotypes to investigate the response of polycyclic aromatic hydrocarbon (PAH)-degrading genes to PAH bioavailability in the overlying water, suspended sediment (SPS), and deposited sediment of the Yangtze River. The freely dissolved concentration, typically used to reflect HOC bioavailability, and total dissolved, as well as sorbed concentrations of PAHs were determined. Phylogenetic analysis showed that all the PAH-ring hydroxylating dioxygenase gene sequences of Gram-negative bacteria (PAH-RHD[GN]) were closely related to nahAc, nagAc, nidA, and uncultured PAH-RHD genes. The PAH-RHD[GN] gene diversity as well as nahAc and nidA gene copy numbers decreased in the following order: deposited sediment>SPS>overlying water. The nahAc and nidA gene abundance was not significantly correlated with environmental parameters but was significantly correlated with the bioavailable existing forms of naphthalene and pyrene in the three phases. The nahAc gene copy numbers in the overlying water and deposited sediment were positively correlated with freely dissolved naphthalene concentrations in the overlying and pore water phases, respectively, and so were nidA gene copy numbers. This study suggests that the distribution and abundance of HOC-degrading bacterial population depend on the HOC bioavailability in aquatic environments. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Polycyclic aromatic hydrocarbons (PAHs), their transfer into and dislocation within soil; Eintraege von polyzyklischen aromatischen Kohlenwasserstoffen (PAH) und ihre Verlagerung im Boden

    Energy Technology Data Exchange (ETDEWEB)

    Duerbeck, H.W.; Niehaus, R.; Mueller, U.; Bueker, I. [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Angewandte Physikalische Chemie

    1997-12-31

    In order to assess the terrestrial hazard potential of polycyclic aromatic hydrocarbons (PAHs), it is vital to investigate their nuisance concentrations and deposition to soil and plants as well as their dislocation in soil. This was the object of the first part of the research programme ``Locational evaluation of chemical soil pollution``, conducted by the national research institutions. It was headed ``Analysis of exposure`` and comprised the following individual contributions: 1. Integrated long-term measurements of polycyclic aromatic hydrocarbons in soil air at ground level (FZJ), 2. Determination of PAH nuisance concentrations at the Scheyern experimental station as well as at the motorway by-passing Munich to the east (A 99), near Kirchheim (GSF), 3. Investigations regarding PAH exposure via the air pathway and inclusion of acquired data in substance flows made up for the east-German dry zone (Bad Lauchstaedt), (UFZ), 4. Simulation of PAH concentration and deposition in south-western Germany (FZK). (orig./SR) [Deutsch] Zur Abschaetzung des Gefaehrdungspotentials von Polycyclischen Aromatischen Kohlenwasserstoffen (PAK) im terrestrischen Bereich sind daher Untersuchungen ueber die Immissionskonzentrationen und die Deposition auf Boeden und Pflanzen sowie ueber ihre Verlagerung im Boden von essentieller Bedeutung. Die Bearbeitung dieser Thematik erfolgte im Teilbereich I `Eintragsanalyse` des AGF-Programms `Standortgerechte Bewertung chemischer Bodenbelastungen` mit folgenden Einzelbeitraegen: 1. Integrierende Langzeitmessung von Polycyclischen Aromatischen Kohlenwasserstoffen in bodennaher Luft, (FZJ) 2. Bestimmung der PAH-Immissionskonzentrationen am Versuchsgut Scheyern sowie an der oestlichen Autobahnumgehung von Muenchen (A 99) bei Kirchheim, (GSF) 3. Untersuchungen zum Eintrag von PAH ueber den Luftpfad und Einbeziehung der Daten in Stoffkreislaeufe im Mitteldeutschen Trockengebiet (Bad Lauchstaedt), (UFZ) 4. Simulation der PAH-Konzentration und

  12. Use of compound-specific stable carbon isotope ratio measurements of asphaltene-bound polycyclic aromatic hydrocarbons (PAHs) as a novel aid to source apportionment of environmental PAHs

    Energy Technology Data Exchange (ETDEWEB)

    C. Sun; C. Snape; M. Cooper; W. Ivwurie [University of Nottingham, Nottingham (United Kingdom). Nottingham Energy & Fuel Centre

    2005-07-01

    In this study, the PAHs from hydropyrolysis of asphaltenes from different primary sources (e.g. crude oil, low and high temperature coal tars) were characterized by their molecular distributions and {sup 13}C/{sup 12}C isotope ratios. It was found that for all oil samples, the molecular and isotopic profiles for their asphaltene-derived PAHs are both similar to those observed for their contained free aromatics, with {sup 13}C-isotopic values varying from -25 to -27{per_thousand} for the Nigerian and -27 to -30{per_thousand} for North Sea oil samples. For low and high temperature coal tar samples, however, similar molecular but different isotopic profiles were observed for their asphaltene-bound PAHs. The free aromatics are significantly isotopically lighter (by nearly -3{per_thousand}) than their asphaltene-derived counterparts having isotopic values typically between -22 and -23{per_thousand}