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Academic literature on the topic 'Polycyclic aromatic compounds'

Author: Grafiati

Published: 4 June 2021

Last updated: 26 July 2024

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Journal articles on the topic "Polycyclic aromatic compounds"

1

Vácha, R., J. Čechmánková, and J. Skála. "Polycyclic aromatic hydrocarbons in soil and selected plants." Plant, Soil and Environment 56, No. 9 (September 16, 2010): 434–43. http://dx.doi.org/10.17221/7/2010-pse.

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The influence of soil load with polycyclic aromatic hydrocarbons (PAHs) on their contents in selected plants was investigated. A set of experiments was realized in three years. The influence of extreme soil load with PAHs (soil contaminated by floods and sludge application) on their content in plants was observed in a pot trial. A laboratory column extract trial investigated PAHs transfer from the soil into soil solution in different conditions. The results showed that the transfer of PAHs into plants is influenced mainly by chemical characteristics of the substances (the number and position of aromatic nuclei); by soil characteristics (content and quality of soil organic matter) and by plant characteristics (plant species and plant bodies). The roots of tested plants were loaded with PAHs thanks to the transfer of less-nuclei compounds (2–3 nuclei) in soil solution into the roots and thanks to the binding of more nuclei compounds (4–6 nuclei) on organic substances in epidermis and primary bark of roots. These results were confirmed by a laboratory column trial.

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Li, Lijie, Wenjuan Niu, Hongbin Cong, Haibo Meng, Zhiyou Niu, Xiuli Shen, Licong Cao, and Xianrui Kong. "Effects of pyrolysis temperature on the release characteristics of polycyclic aromatic hydrocarbons during pyrolysis of corn stover pellet." BioResources 18, no. 1 (January 30, 2023): 2112–36. http://dx.doi.org/10.15376/biores.18.1.2112-2136.

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The release characteristics of polycyclic aromatic hydrocarbons during the pyrolysis of biomass remain poorly understood. This study investigated the effects of pyrolysis temperature on the polycyclic aromatic hydrocarbon release characteristics by analyzing both the transient vapor products and the physicochemical properties of corresponding biochar from the pyrolysis of corn stover pellets. The results revealed that the transient volatile compounds mainly included phenols, ketones, acids, furans, aldehydes, substances containing benzene ring, polycyclic aromatic compounds, and gaseous products. A range of 2 to 4 ring polycyclic aromatic hydrocarbons were generated at 400 to 700 °C with the peak at 560 °C, and the sum of relative content of polycyclic aromatic hydrocarbons ranged from 0.23% to 40.36%. For the biochar, the carbonization stage (400 to 700 °C) of corn stover pellets was further divided into three evolutionary stages, including the preliminary carbonization stage (380 to 480 °C), amorphous carbon structure stage (480 to 600 °C), and the stage of dehydrogenation and growth of aromatic rings (600 to 700 °C).The relationship between polycyclic aromatic hydrocarbon release in volatile compounds and H/C ratio of the biochar could be described by a power function.

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N, Hedid. "Fungal Biodegradation of Polycyclic Aromatic Hydrocarbons (PAHs)." Medicinal & Analytical Chemistry International Journal 8, no. 1 (March 24, 2024): 1–6. http://dx.doi.org/10.23880/macij-16000192.

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For many years, PAHs have been the subject of intense controversy throughout the world, due to their high toxicity and their presence in almost all environmental media. Their hazardous nature has given rise to a number of legal requirements throughout the world aimed at effectively reducing their content in foodstuffs and certain everyday consumer products. However, technologies for remediating PAH-contaminated soils use chemical and mechanical approaches that are extremely costly and not very environmentally friendly. That's why research is currently focusing on biological approaches that can provide effective, low-cost treatment for PAH-contaminated soils, and avoid environmental repercussions as far as possible. The aim of this paper is to shed light on a biological approach to the treatment of PAHs that is still in its infancy, but which is already showing great promise: biodegradation by fungi, which differ from other organisms in that they secrete enzymes that give them the ability to feed in environments inaccessible to other kingdoms, and to absorb toxic PAH chemicals from the soil and transform them into less harmful compounds.

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Ouyang, Xiao Dong, Shi Bao Dong, Li Ming Hu, and Zhi Min Zong. "Analysis of Acetone Extract From Shenfu by GC/MS and FTIR." Advanced Materials Research 356-360 (October 2011): 1285–88. http://dx.doi.org/10.4028/www.scientific.net/amr.356-360.1285.

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The acetone extracts from Shenfu coal (SFC) of China was filtered into filtrate and cake, and analyzed by GC/MS and FTIR respectively. The results indicate that: The GC/MS identifiable fraction mainly consists of polycyclic aromatics with 2-4 rings and their alkyl derivatives as main components, and polar oxygen compounds with ketones and esters as main components. A variety of nitrogen compounds and several compounds containing phosphor, sulfur, and chlorine were identified. IR spectrum shows that functional groups including hydroxyl, carbonyl, polycyclic aromatic ring, methylene, methyl, etc. are among the main groups of GC/MS unidentified fraction.

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OONISHI, Isao, and Shoji FUJISAWA. "Molecular deformation of polycyclic aromatic compounds." Nihon Kessho Gakkaishi 32, no. 4 (1990): 207–12. http://dx.doi.org/10.5940/jcrsj.32.207.

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Donkin, P. "Chemical analysis of polycyclic aromatic compounds." Environmental Pollution 69, no. 4 (1991): 356–57. http://dx.doi.org/10.1016/0269-7491(91)90125-g.

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Helweg, Christian, Torben Nielsen, and Poul Erik Hansen. "Determination ofKowof Substituted Polycyclic Aromatic Compounds." Polycyclic Aromatic Compounds 12, no. 3 (September 1997): 187–200. http://dx.doi.org/10.1080/10406639708233835.

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Hudgins, Douglas M. "Interstellar Polycyclic Aromatic Compounds and Astrophysics." Polycyclic Aromatic Compounds 22, no. 3-4 (January 2002): 469–88. http://dx.doi.org/10.1080/10406630290103852.

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Achten, Christine, and Jan T. Andersson. "Overview of Polycyclic Aromatic Compounds (PAC)." Polycyclic Aromatic Compounds 35, no. 2-4 (March 15, 2015): 177–86. http://dx.doi.org/10.1080/10406638.2014.994071.

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Bhatia, A. L., H. Tausch, and G. Stehlik. "Mutagenicity of chlorinated polycyclic aromatic compounds." Ecotoxicology and Environmental Safety 14, no. 1 (August 1987): 48–55. http://dx.doi.org/10.1016/0147-6513(87)90082-0.

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Dissertations / Theses on the topic "Polycyclic aromatic compounds"

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Freeman, David John. "Polycyclic aromatic compounds in flames." Thesis, University of Cambridge, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308234.

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Tucker, Sheryl A. (Sheryl Ann). "Spectroscopic Properties of Polycyclic Aromatic Compounds." Thesis, University of North Texas, 1994. https://digital.library.unt.edu/ark:/67531/metadc278682/.

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The fluorescence spectrum of many polycyclic aromatic compounds (PACs) depends upon solvent polarity. The emission spectrum of PAC monomers consists of several major vibronic bands labeled I, II, etc., in progressive order. Emission intensity enhancement of select bands is observed in polar solvents.

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Reginato, Nada McGlinchey Michael J. "Polycyclic compounds of manganese /." *McMaster only, 2003.

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Warner, Stephanie D. "Photochemical degradation of selected polycyclic aromatic compounds." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=84446.

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Polycyclic aromatic hydrocarbons and many of their derivatives are considered to be ubiquitous environmental pollutants, which often exhibit mutagenic and/or carcinogenic activity. In the atmosphere, photolysis is generally considered to be the dominant degradation pathway for these pollutants. The photochemical behaviours of benzo(a)pyrene, benzo(b)fluoranthene and benzo(k)fluoranthene have been examined in the laboratory. This study was complemented by an analysis of ambient air samples collected in the vicinity of a Horizontal Stud Soderberg aluminum smelter in Beauharnois, Quebec. Benzo(a)pyrene is much more reactive in the presence of light when compared to the fluoranthene compounds. The products were identified as the 1,6-, 3,6- and 6,12-benzo(a)pyrenediones. An analysis of the ambient air samples revealed the prevalence of benzo(b)fluoranthene in the emissions from the aluminum smelter. Its relatively high abundance and resistance to degradation indicates that it will be a suitable indicator to represent total polycyclic aromatic hydrocarbon levels at the smelter. The photochemical behaviour of a series of nitropolycyclic aromatic hydrocarbons has also been investigated. The photoreactivity of these compounds in solution and adsorbed onto a surface has previously been associated with the torsion angle of the nitro group with respect to the aromatic moiety. Initially, through a combination of spectroscopic techniques and semi-empirical calculations, the orientation of the nitro group in each compound was determined. Solution studies were inconclusive in determining the role of the torsion angle of the nitro group in influencing the photochemical degradation. However, when the compounds were adsorbed onto a surface, no relationship could be established between photoreactivity and the orientation. The stability of these compounds was also examined during the sampling process. In an effort to further examine the relationship between th

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Davies, Ilona Lynn. "Analysis of polycyclic aromatic compounds by multidimensional chromatography." Thesis, University of Leeds, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328575.

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Robertson, Charles Ray. "Chemistry towards curved polycyclic aromatic hydrocarbons." abstract and full text PDF (free order & download UNR users only), 2006. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1438911.

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Blumire, Nigel James. "Intramolecular radical additions to aromatic compounds." Thesis, University of Southampton, 2003. https://eprints.soton.ac.uk/420074/.

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This thesis is concerned with the development of cyclisation strategies that allow entry to polycyclic heterocycles and medium sized ring systems. Radical additions to pyridines are developed and methodologies explore the differences between the homolysis of C-Br and C-I bonds. Mechanisms are described for the unexpected ipso additions to the pyridines. Work towards the synthesis of the stegnans and dimethylgomisin illustrates the attempts to utilise the ipso addition to form medium sized ring systems. A new method of synthesising these medium sized ring systems is discussed. Progress towards a general methodology is described and shows the opportunities for which it could be utilised. A literature review of the synthesis of heterocycles via radical cyclisations is presented.

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Brown, James S. "The chemistry of nickel on the edge of polycyclic aromatic hydrocarbons /." free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p1422914.

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Cho, Don Mark. "Partially fluorinated polycyclic aromatic compounds synthesis and supramolecular behavior /." Lexington, Ky. : [University of Kentucky Libraries], 2006. http://lib.uky.edu/ETD/ukychem2007t00544/Cho_thesis.pdf.

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Thesis (M.S.)--University of Kentucky, 2006.
Title from document title page (viewed on February 27, 2007). Document formatted into pages; contains: xiv, 69 p. : ill. (some col.). Includes abstract and vita. Includes bibliographical references (p. 64-68).

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Chaolumen. "Synthesis and Properties of Electron-Deficient Polycyclic Aromatic Compounds." 京都大学 (Kyoto University), 2017. http://hdl.handle.net/2433/225617.

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Books on the topic "Polycyclic aromatic compounds"

1

Polycyclic aromatic hydrocarbons. New York: Wiley-VCH, 1997.

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B, Ebert Lawrence, American Chemical Society. Division of Petroleum Chemistry., and American Chemical Society Meeting, eds. Polynuclear aromatic compounds. Washington, DC: American Chemical Society, 1988.

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Harvey, Ronald G. Polycyclic aromatic hydrocarbons. New York: Wiley-VCH, 1997.

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IARC Working Group on the Evaluation of the Carcinogenic Risk of Chemicals to Humans (1984 Lyon, France). Polynuclear aromatic compounds. [Lyon, France]: International Agency for Research on Cancer, 1985.

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5

C, Bosch L., and White C. M, eds. Nitrated polycyclic aromatic hydrocarbons. Heidelberg: A. Huethig, 1985.

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Karcher, W., ed. Spectral Atlas of Polycyclic Aromatic Compounds. Dordrecht: Springer Netherlands, 1988. http://dx.doi.org/10.1007/978-94-009-1263-2.

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Karcher, W., J. Devillers, Ph Garrigues, and J. Jacob, eds. Spectral Atlas of Polycyclic Aromatic Compounds. Dordrecht: Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-2668-7.

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Tuan, Vo-Dinh, ed. Chemical analysis of polycyclic aromatic compounds. New York: Wiley, 1989.

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9

Tobe, Y. Aromatic ring assemblies, polycyclic aromatic hydrocarbons, and conjugated polyenes. Stuttgart: Thieme, 2008.

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10

Polycyclic aromatic hydrocarbons: Chemistry and carcinogenicity. Cambridge: Cambridge University Press, 1991.

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Book chapters on the topic "Polycyclic aromatic compounds"

1

Šimko, Peter. "Polycyclic Aromatic Hydrocarbons." In Analysis of Endocrine Disrupting Compounds in Food, 429–45. Oxford, UK: Wiley-Blackwell, 2012. http://dx.doi.org/10.1002/9781118346747.ch19.

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Karcher, W. "Introduction." In Spectral Atlas of Polycyclic Aromatic Compounds, 1–3. Dordrecht: Springer Netherlands, 1988. http://dx.doi.org/10.1007/978-94-009-1263-2_1.

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Karcher, W. "Information for Users." In Spectral Atlas of Polycyclic Aromatic Compounds, 4–14. Dordrecht: Springer Netherlands, 1988. http://dx.doi.org/10.1007/978-94-009-1263-2_2.

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Karcher, W. "Acknowledgements." In Spectral Atlas of Polycyclic Aromatic Compounds, 15. Dordrecht: Springer Netherlands, 1988. http://dx.doi.org/10.1007/978-94-009-1263-2_3.

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Karcher, W. "Data Presentation." In Spectral Atlas of Polycyclic Aromatic Compounds, 16–829. Dordrecht: Springer Netherlands, 1988. http://dx.doi.org/10.1007/978-94-009-1263-2_4.

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Karcher, W. "Introduction." In Spectral Atlas of Polycyclic Aromatic Compounds, 1–2. Dordrecht: Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-2668-7_1.

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Karcher, W., J. Devillers, Ph Garrigues, and J. Jacob. "Information for Users." In Spectral Atlas of Polycyclic Aromatic Compounds, 3–16. Dordrecht: Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-2668-7_2.

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Karcher, W., J. Devillers, Ph Garrigues, and J. Jacob. "Acknowledgements." In Spectral Atlas of Polycyclic Aromatic Compounds, 17. Dordrecht: Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-2668-7_3.

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Karcher, W., J. Devillers, Ph Garrigues, and J. Jacob. "Data Presentation." In Spectral Atlas of Polycyclic Aromatic Compounds, 18–1103. Dordrecht: Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-2668-7_4.

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Garms, C., and W. Francke. "Syntheses of 13C-Labelled Polycyclic Aromatic Compounds." In Treatment of Contaminated Soil, 95–131. Berlin, Heidelberg: Springer Berlin Heidelberg, 2001. http://dx.doi.org/10.1007/978-3-662-04643-2_9.

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Conference papers on the topic "Polycyclic aromatic compounds"

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Jáuregui-López, Irati, Kizkitza Insausti, María-José Beriain, and Miguel Beruete. "Polycyclic Aromatic Hidrocarbons Identification with THz Metageometries." In Optical Sensors. Washington, D.C.: Optica Publishing Group, 2022. http://dx.doi.org/10.1364/sensors.2022.sm3c.2.

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In this work, a labyrinth metageometry is experimentally tested as Polycyclic Aromatic Hydrocarbons THz detection and identification, with a design able to detect different concentrations and distinguish between different compounds at the same concentration.

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SAKAI, Takayuki, and Kiriko KASHIWAKURA. "77 Basic Investigation of Particulate Matters (O-PM)) and Polycyclic Aromatic Hydrocarbons Emitted by Two-stroke Motorcycles." In Small Engine Technology Conference & Exposition. 10-2 Gobancho, Chiyoda-ku, Tokyo, Japan: Society of Automotive Engineers of Japan, 2002. http://dx.doi.org/10.4271/2002-32-1846.

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<div class="htmlview paragraph">Characteristics of mass emission of unburned Oil-Particulate Matter and polycyclic aromatic hydrocarbons from two-stroke scooter were investigated. The tests were carried out under with and without oxidation catalyst and various air-fuel ratio ranging from 12 to 16 at 50:1 of fuel-oil mixing ratio for easy sampling. Unburned Oil-Particulate Matter and 4- to 7-rings polycyclic aromatic hydrocarbons were trapped on filter. These compounds were analyzed by high performance liquid chromatography with fluorescence detector.</div> <div class="htmlview paragraph">Mass emission of polycyclic aromatic hydrocarbons and unburned Oil-Particulate Matter tends to decrease as air-fuel ratio which increased up to stoichiometric ratio. The highest conversion ratio of unburned Oil-Particulate Matter on the oxidation catalyst was 64%. Conversion ratio of polycyclic aromatic hydrocarbons increased as rings are smaller. However, in one case of this test, some of 5-rings aromatic hydrocarbons or higher compounds showed a tendency to increase by the oxidation catalyst.</div>

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Alam, Md Samrat, Jason Ahad, and Colin Cooke. "Compound-Specific Isotope Analysis Reveals Sources of Polycyclic Aromatic Compounds in the Athabasca River." In Goldschmidt2023. France: European Association of Geochemistry, 2023. http://dx.doi.org/10.7185/gold2023.18946.

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Olsen, L., L. Jaycox, and C. Neumeister. "71. Development of Analytical Methods for Polycyclic Aromatic Compounds and Sulfur Compounds in Asphalt Fume." In AIHce 1996 - Health Care Industries Papers. AIHA, 1999. http://dx.doi.org/10.3320/1.2765184.

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Jalkian, Rafi D., and M. Bonner Denton. "HPLC Determination Of Polycyclic Aromatic Compounds By Fluorescence Detected With A Charge-Coupled Device." In OE/LASE '89, edited by E. R. Menzel. SPIE, 1989. http://dx.doi.org/10.1117/12.951546.

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Wang, Heyu, Zhonglei Li, Mingsheng Fan, Shuofan Zhou, You Wu, Boxue Du, and Zhuoran Yang. "Effect of Polycyclic Aromatic Compounds Content on Electrical Tree and Partial Discharge of XLPE." In 2022 IEEE 4th International Conference on Dielectrics (ICD). IEEE, 2022. http://dx.doi.org/10.1109/icd53806.2022.9863498.

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Hanley, K., J. Fernback, J. Meeker, M. McClean, and R. Herrick. "399. Personal Exposure to Polycyclic Aromatic Compounds and Particle size Distributions in Asphalt Paving Fume." In AIHce 2002. AIHA, 2002. http://dx.doi.org/10.3320/1.2766344.

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Kleiboehmer, W., Norbert Huesers, Michael Arnold, and Karl Cammann. "New method for the determination of polycyclic aromatic hydrocarbons and halogenorganic compounds in air samples." In Environmental Sensing '92, edited by Tuan Vo-Dinh and Karl Cammann. SPIE, 1993. http://dx.doi.org/10.1117/12.140291.

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Hanley, K., D. Almaguer, G. Burr, and K. Wallingford. "72. Field Testing Analytical Methods for Polycyclic Aromatic Compounds and Sulfur Compounds During Conventional and Crumb-Rubber-Modified Asphalt Paving." In AIHce 1996 - Health Care Industries Papers. AIHA, 1999. http://dx.doi.org/10.3320/1.2765185.

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Smyth, Kermit C., and J. Houston Miller. "Ultraviolet fluorescence measurements of large molecules in diffusion flames." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1985. http://dx.doi.org/10.1364/oam.1985.thm5.

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Optical measurements in combustion environments have been very successful for detection of molecules containing two and three atoms, but no species-specific results have been reported for larger compounds. However, intermediate-size hydrocarbons as a group have been detected by laser-induced broadband fluorescence in the visible region. The observed spectra have been widely attributed to polycyclic aromatic hydrocarbons, which are thought to be important in soot formation chemistry as precursors and perhaps as building blocks. Recently, we extended these fluorescence measurements to the ultraviolet region as part of an investigation of the soot inception zone in laminar diffusion flames. Detailed concentration profiles have been determined in a methane–air flame using a variety of optical and mass spectrometric techniques. Broadband ultraviolet emission in the 300-400-nm region is observed on excitation at 282 nm. The spatial profiles of this fluorescence exhibit two distinct contributions, which show different behavior as a function of height above the burner. One contribution is located in the soot inception zone and overlaps the broadband visible fluorescence profile, whereas the second feature is unconnected with chemical growth processes and arises from a stable combustion by-product. Many candidates exist for the observed ultraviolet fluorescence including polyenes, polyynes, and the polycyclic aromatic hydrocarbons.

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Reports on the topic "Polycyclic aromatic compounds"

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Cesar, J. R., and O. H. Ardakani. Organic geochemistry of the Montney Formation: new insights about the source of hydrocarbons, their accumulation history and post accumulation processes. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/329788.

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This study consists of a non-traditional molecular and stable isotope approach to analyze organic matter (soluble bitumen and produced oil/condensate) from the Montney Formation low-permeability reservoirs, with the purpose of identifying source(s) of hydrocarbons, accumulation history and post accumulation processes. The same approach bases on the distribution of compound classes such as aromatic carotenoids, polycyclic aromatic hydrocarbons (PAHs), bicyclic alkanes, and oxygen-polar compounds. The geochemical screening has been enhanced with performing compound specific isotope analysis (CSIA) of n-alkanes and selected aromatic hydrocarbons. Widely spread PAHs, the presence of molecular indicators of euxinia, and hydrocarbon mixtures identified using CSIA profiles, are some of the key findings from this research, which will improve our understanding of the Montney petroleum system(s).

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Lotufo, Guilherme, Mandy Michalsen, Danny Reible, Philip Gschwend, Upal Ghosh, Alan Kennedy, Kristen Kerns, et al. Interlaboratory study of polyethylene and polydimethylsiloxane polymeric samplers for ex situ measurement of freely dissolved hydrophobic organic compounds in sediment porewater. Engineer Research and Development Center (U.S.), May 2024. http://dx.doi.org/10.21079/11681/48512.

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We evaluated the precision and accuracy of multilaboratory measurements for determining freely dissolved concentrations (Cfree) of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in sediment porewater using polydimethylsiloxane and low-density polyethylene polymeric samplers. Four laboratories exposed performance reference compound (PRC) preloaded polymers to actively mixed and static ex situ sediment for approximately one month or more. For Cfree results, intralaboratory precision was high for single compounds; most PAHs and PCBs variability was low. Variability was higher for most hydrophobic PAHs, PCBs, and naphthalene, which were present at low concentrations and required larger PRC-based corrections. Intra- and interlaboratory variability between methods was low. Cfree polymer equilibrium was achieved in approximately one month during active exposures, suggesting using PRCs may be avoided for ex situ analysis using comparable active exposure; however, such testing may not reflect field conditions. Polymer-derived Cfree concentrations for most PCBs and PAHs averaged within a factor of 2 compared with concentrations in isolated porewater; difference factors of up to 6 were observed for naphthalene and the most hydrophobic PAHs and PCBs. Cfree results were similar for academic and private sector laboratories. The accuracy and precision demonstrated for determinating Cfree using polymer sampling are anticipated to increase regulatory acceptance and confidence.

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Kyllönen, Katriina, Karri Saarnio, Ulla Makkonen, and Heidi Hellén. Verification of the validity of air quality measurements related to the Directive 2004/107/EC in 2019-2020 (DIRME2019). Finnish Meteorological Institute, 2020. http://dx.doi.org/10.35614/isbn.9789523361256.

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This project summarizes the results from 2000–2020and evaluates the trueness andthequality control (QC) procedures of the ongoing polycyclic aromatic hydrocarbon (PAH)and trace element measurements in Finlandrelating to Air Quality (AQ) Directive 2004/107/EC. The evaluation was focused on benzo(a)pyrene and other PAH compounds as well as arsenic, cadmium and nickel in PM10and deposition. Additionally, it included lead and other metals in PM10and deposition, gaseous mercury and mercury deposition, andbriefly other specificAQ measurements such as volatile organic compounds (VOC)and PM2.5chemical composition. This project was conducted by the National Reference Laboratory on air quality and thiswas the first time these measurements were assessed. A major part of the project was field and laboratory audits of the ongoing PAH and metal measurements. Other measurements were briefly evaluated through interviews and available literature. In addition, the national AQ database, the expertise of local measurement networks and related publications were utilised. In total, all theseven measurement networks performing PAH and metal measurements in 2019–2020took part in the audits. Eleven stations were audited while these measurements are performed at 22 AQ stations in Finland. For the large networks, one station was chosen to represent the performance of the network. The audits included also six laboratories performing the analysis of the collected samples. The audits revealed the compliance of the measurements with the AQ Decree 113/2017, Directive 2004/107/EC and Standards of the European Committee for Standardization(CEN). In addition, general information of the measurements, instruments and quality control procedures were gained. The results of the laboratory audits were confidential,but this report includes general findings, and the measurement networks were informed on the audit results with the permission of the participating laboratories. As a conclusion, the measurementmethodsusedwere mainly reference methods. Currently, all sampling methods were reference methods; however, before 2018 three networks used other methods that may have underestimated concentrations. Regarding these measurements, it should be noted the results are notcomparable with the reference method. Laboratory methods were reference methods excluding two cases, where the first was considered an acceptable equivalent method. For the other, a change to a reference method was strongly recommended and this realized in 2020. For some new measurements, the ongoing QC procedures were not yet fully established, and advice were given. Some networks used consultant for calibration and maintenance, and thus theywere not fully aware of the QC procedures. EN Standards were mostly followed. Main concerns were related to the checks of flow and calculation of measurement uncertainty, and suggestions for improvement were given. When the measurement networks implement the recommendations given inthe audits, it can be concluded that the EN Standards are adequately followed in the networks. In the ongoing sampling, clear factors risking the trueness of the result were not found. This applies also for the laboratory analyses in 2020. One network had concentrations above the target value, and theindicative measurementsshould be updated to fixed measurements.

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Jalkanen, Jukka-Pekka, Erik Fridell, Jaakko Kukkonen, Jana Moldanova, Leonidas Ntziachristos, Achilleas Grigoriadis, Maria Moustaka, et al. Environmental impacts of exhaust gas cleaning systems in the Baltic Sea, North Sea, and the Mediterranean Sea area. Finnish Meteorological Institute, 2024. http://dx.doi.org/10.35614/isbn.9789523361898.

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Abstract:

Description: Shipping is responsible for a range of different pressures affecting air quality, climate, and the marine environment. Most social and economic analyses of shipping have focused on air pollution assessment and how shipping may impact climate change and human health. This risks that policies may be biased towards air pollution and climate change, whilst impacts on the marine environment are not as well known. One example is the sulfur regulation introduced in January 2020, which requires shipowners to use a compliant fuel with a sulfur content of 0.5% (0.1% in SECA regions) or use alternative compliance options (Exhaust Gas Cleaning Systems, EGCS) that are effective in reducing sulfur oxide (SOx) emissions to the atmosphere. The EGCS cleaning process results in large volumes of discharged water that includes a wide range of contaminants. Although regulations target SOx removal, other pollutants such as polycyclic aromatic hydrocarbons (PAHs), metals and combustion particles are removed from the exhaust to the wash water and subsequently discharged to the marine environment. Based on dilution series of the Whole Effluent Testing (WET), the impact of the EGCS effluent on marine invertebrate species and on phytoplankton was found to vary between taxonomic groups, and between different stages of the invertebrate life cycle. Invertebrates were more affected than phytoplankton, and the most sensitive endpoint detected in the present project was the fertilisation of sea urchin eggs, which were negatively affected at a sample dilution of 1 : 1,000,000. Dilutions of 1: 100,000 were harmful to early development of several of the tested species, including mussels, polychaetes, and crustaceans. The observed effects at these low concentrations of EGCS effluent were reduced egg production, and deformations and abnormal development of the larvae of the species. The ecotoxicological data produced in the EMERGE project were used to derive Predicted No Effect Concentration values. Corresponding modelling studies revealed that the EGCS effluent can be considered as a single entity for 2-10 days from the time of discharge, depending on the environmental conditions like sea currents, winds, and temperature. Area 10-30 km outside the shipping lanes will be prone to contaminant concentrations corresponding to 1 : 1,000,000 dilution which was deemed harmful for most sensitive endpoints of WET experiments. Studies for the Saronikos Gulf (Aegean Sea) revealed that the EGCS effluent dilution rate exceeded the 1 : 1,000,000 ratio 70% of the time at a distance of about 10 km from the port. This was also observed for 15% of the time within a band of 10 km wide along the shipping lane extending 500 km away from the port of Piraeus. When mortality of adult specimens of one of the species (copepod Acartia tonsa) was used as an endpoint it was found to be 3-4 orders of magnitude less sensitive to EGCS effluent than early life stage endpoints like fertilisation of eggs and larval development. Mortality of Acartia tonsa is commonly used in standard protocols for ecotoxicological studies, but our data hence shows that it seriously underestimates the ecologically relevant toxicity of the effluent. The same is true for two other commonly used and recommended endpoints, phytoplankton growth and inhibition of bioluminescence in marine bacteria. Significant toxic effects were reached only after addition of 20-40% effluent. A marine environmental risk assessment was performed for the Öresund region for baseline year 2018, where Predicted Environmental Concentrations (PECs) of open loop effluent discharge water were compared to the PNEC value. The results showed modelled concentrations of open loop effluent in large areas to be two to three orders of magnitude higher than the derived PNEC value, yielding a Risk Characterisation Ratio of 500-5000, which indicates significant environmental risk. Further, it should be noted that between 2018-2022 the number of EGCS vessels more than quadrupled in the area from 178 to 781. In this work, the EGCS discharges of the fleet in the Baltic Sea, North Sea, the English Channel, and the Mediterranean Sea area were studied in detail. The assessments of impacts described in this document were performed using a baseline year 2018 and future scenarios. These were made for the year 2050, based on different projections of transport volumes, also considering the fuel efficiency requirements and ship size developments. From the eight scenarios developed, two extremes were chosen for impact studies which illustrate the differences between a very high EGCS usage and a future without the need for EGCS while still compliant to IMO initial GHG strategy. The scenario without EGCS leads to 50% reduction of GHG emissions using low sulfur fuels, LNG, and methanol. For the high EGCS adoption scenario in 2050, about a third of the fleet sailing the studied sea areas would use EGCS and effluent discharge volumes would be increased tenfold for the Baltic Sea and hundredfold for the Mediterranean Sea when compared to 2018 baseline discharges. Some of the tested species, mainly the copepods, have a central position in pelagic food webs as they feed on phytoplankton and are themselves the main staple food for most fish larvae and for some species of adult fish, e.g., herring. The direct effect of the EGSE on invertebrates will therefore have an important indirect effect on the fish feeding on them. Effects are greatest in and near shipping lanes. Many important shipping lanes run close to shore and archipelago areas, and this also puts the sensitive shallow water coastal ecosystems at risk. It should be noted that no studies on sub-lethal effects of early 19 life stages in fish were included in the EMERGE project, nor are there any available data on this in the scientific literature. The direct toxic effects on fish at the expected concentrations of EGCS effluent are therefore largely unknown. According to the regional modelling studies, some of the contaminants will end up in sediments along the coastlines and archipelagos. The documentation of the complex chemical composition of EGCS effluent is in sharp contrast to the present legislation on threshold levels for content in EGCS effluent discharged from ships, which includes but a few PAHs, pH, and turbidity. Traditional assessments of PAHs in environmental and marine samples focus only on the U.S. Environmental Protection Agency (EPA) list of 16 priority PAHs, which includes only parent PAHs. Considering the complex PAHs assemblages and the importance of other related compounds, it is important to extend the EPA list to include alkyl-PAHs to obtain a representative monitoring of EGCS effluent and to assess the impact of its discharges into the marine environment. An economic evaluation of the installation and operational costs of EGCS was conducted noting the historical fuel price differences of high and low sulfur fuels. Equipment types, installation dates and annual fuel consumption from global simulations indicated that 51% of the global EGCS fleet had already reached break-even by the end of 2022, resulting in a summarised profit of 4.7 billion €2019. Within five years after the initial installation, more than 95% of the ships with open loop EGCS reach break-even. The pollutant loads from shipping come both through atmospheric deposition and direct discharges. This underlines the need of minimising the release of contaminants by using fuels which reduce the air emissions of harmful components without creating new pollution loads through discharges. Continued use of EGCS and high sulfur fossil fuels will delay the transition to more sustainable options. The investments made on EGCS enable ships to continue using fossil fuels instead of transitioning away from them as soon as possible as agreed in the 2023 Dubai Climate Change conference. Continued carriage of residual fuels also increases the risk of dire environmental consequences whenever accidental releases of oil to the sea occur.

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Investigation of the distribution of organochlorine and polycyclic aromatic hydrocarbon compounds in the Lower Columbia River using semipermeable-membrane devices. US Geological Survey, 1999. http://dx.doi.org/10.3133/wri994051.

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Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory : determination of polycyclic aromatic hydrocarbon compounds in sediment by gas chromatography/mass spectrometry. US Geological Survey, 2004. http://dx.doi.org/10.3133/wri034318.

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