Polycyclic Aromatic Hydrocarbons (Pahs) and to Emphasize the Human Health Effects That May Result from Exposure to Them
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An Improved Process for the Production of Cumene
Europaisches Patentamt European Patent Office © Publication number: 0 537 389 A1 Office europeen des brevets EUROPEAN PATENT APPLICATION © Application number: 91309531.1 int. Ci.5; C07C 2/66, C07C 2/86, C07C 6/12, C07C 15/085 (§) Date of filing: 16.10.91 ® Date of publication of application: @ Applicant: Council of Scientific and Industrial 21.04.93 Bulletin 93/16 Research Rafi Marg @ Designated Contracting States: New Delhi 110 001 (IN) BE DE FR GB IT NL @ Inventor: Pradhan, Ajit Ramchandra National Chemical Laboratory Pune-411008, Maharashtra(IN) Inventor: Rao, Bollapragad Seshagiri National Chemical Laboratory Pune-411008, Maharashtra(IN) 0 Representative: Collier, Jeremy Austin Grey et al J.A.Kemp & Co., 14 South Square, Gray's Inn London WC1R 5LX (GB) 0 An improved process for the production of cumene. © An improved process is disclosed for the preparation of cumene. Cumene is prepared by reacting benzene with a propylating agent in the presence of a catalyst containing metal loaded Zeolite EU-1 in a reactor in the range of a temperature of 150 to 250 °C and a pressure of 1 to 35 atmospheres, the propyl and diisopropylben- zene so formed are separated from the reactor effluent by conventional methods. The diisopropylbenzene is recycled back to the reactor. Simultaneous alkylation and transalkylation reactions occur in a single catalyst bed containing Zeolite EU-1 with a feed containing benzene, propylene and diisopropylbenzene. Cumenes are important chemical precursors in the production of detergents and polymers among others. Oi CO CO IV CO m Rank Xerox (UK) Business Services (3. 10/3.5x/3.0. -
Reactivity and Functionalization of Naphthalene and Anthracene Complexes of {Tpw(NO)(Pme3)}
Reactivity and Functionalization of Naphthalene and Anthracene Complexes of {TpW(NO)(PMe3)} Laura Jessica Strausberg Baltimore, Maryland B.A., Hollins University, 2008 A Dissertation presented to the Graduate Faculty of the University of Virginia in Candidacy for the Degree of Doctor of Philosophy Department of Chemistry University of Virginia July, 2013 ii Abstract Chapter 1 introduces the organic chemistry of aromatic hydrocarbons, with attention paid to regiochemical outcomes of organic reactions. The binding of naphthalene and anthracene to metal complexes is discussed, along with organic transformations they undergo as a result of their complexation. The previous work on osmium and rhenium complexes of naphthalene from the Harman group is explored. Finally, some spectroscopic techniques for exploring the chemistry of {TpW(NO)(PMe3)} complexes of naphthalene and anthracene are introduced. Chapter 2 discusses the highly distorted allyl complexes formed from {TpW(NO)(PMe3)} and the exploration of their origin. Attempts at stereoselectively deprotonating these cationic complexes is also discussed. 2 Chapter 3 describes our study of TpW(NO)(PMe3)(3,4-η -naphthalene)’s ability to undergo a Diels-Alder reaction with N-methylmaleimide. A solvent study suggested that this reaction proceeds by a concerted mechanism. To probe the mechanism further, we synthesized a series of methylated and methoxylated naphthalene complexes and measured their rates of reaction with N-methylmaleimide compared to the parent complex. We found that 1- substitution on the naphthalene increased the rate of cycloaddition, even if the substituent was in the unbound ring, while 2-substitution slowed the reaction rate when in the bound ring. This information is consistent with a concerted mechanism, as a 2-substituted product would be less able to isomerize to form the active isomer for the cycloaddition to occur. -
Aerobic and Anaerobic Bacterial and Fungal Degradation of Pyrene: Mechanism Pathway Including Biochemical Reaction and Catabolic Genes
International Journal of Molecular Sciences Review Aerobic and Anaerobic Bacterial and Fungal Degradation of Pyrene: Mechanism Pathway Including Biochemical Reaction and Catabolic Genes Ali Mohamed Elyamine 1,2 , Jie Kan 1, Shanshan Meng 1, Peng Tao 1, Hui Wang 1 and Zhong Hu 1,* 1 Key Laboratory of Resources and Environmental Microbiology, Department of Biology, Shantou University, Shantou 515063, China; [email protected] (A.M.E.); [email protected] (J.K.); [email protected] (S.M.); [email protected] (P.T.); [email protected] (H.W.) 2 Department of Life Science, Faculty of Science and Technology, University of Comoros, Moroni 269, Comoros * Correspondence: [email protected] Abstract: Microbial biodegradation is one of the acceptable technologies to remediate and control the pollution by polycyclic aromatic hydrocarbon (PAH). Several bacteria, fungi, and cyanobacteria strains have been isolated and used for bioremediation purpose. This review paper is intended to provide key information on the various steps and actors involved in the bacterial and fungal aerobic and anaerobic degradation of pyrene, a high molecular weight PAH, including catabolic genes and enzymes, in order to expand our understanding on pyrene degradation. The aerobic degradation pathway by Mycobacterium vanbaalenii PRY-1 and Mycobactetrium sp. KMS and the anaerobic one, by the facultative bacteria anaerobe Pseudomonas sp. JP1 and Klebsiella sp. LZ6 are reviewed and presented, to describe the complete and integrated degradation mechanism pathway of pyrene. The different microbial strains with the ability to degrade pyrene are listed, and the degradation of Citation: Elyamine, A.M.; Kan, J.; pyrene by consortium is also discussed. -
The Harmful Effects of Food Preservatives on Human Health Shazia Khanum Mirza1, U.K
Journal of Medicinal Chemistry and Drug Discovery ISSN: 2347-9027 International peer reviewed Journal Special Issue Analytical Chemistry Teacher and Researchers Association National Convention/Seminar Issue 02, Vol. 02, pp. 610-616, 8 January 2017 Available online at www.jmcdd.org To Study The Harmful Effects Of Food Preservatives On Human Health Shazia Khanum Mirza1, U.K. Asema2 And Sayyad Sultan Kasim3. 1 -Research student , Dept of chemistry, Maulana Azad PG & Research centre, Aurangabad. 2-3 -Assist prof. Dept of chemistry,Maulana Azad college Arts sci & com.Aurangabad. ABSTRACT Food chemistry is the study of chemical processes and interactions of all biological and non- biological components. Food additives are chemicals added to foods to keep them fresh or to enhance their color, flavor or texture. They may include food colorings, flavor enhancers or a range of preservatives .The chemical added to a particular food for a particular reason during processing or storage which could affect the characteristics of the food, or become part of the food Preservatives are additives that inhibit the growth of bacteria, yeasts, and molds in foods. Additives and preservatives are used to maintain product consistency and quality, improve or maintain nutritional value, maintain palatability and wholesomeness, provide leavening(yeast), control pH, enhance flavour, or provide colour Some additives have been used for centuries; for example, preserving food by pickling (with vinegar), salting, as with bacon, preserving sweets or using sulfur dioxide as in some wines. Some preservatives are known to be harmful to the human body. Some are classified as carcinogens or cancer causing agents. Keywords : Food , Food additives, colour, flavour , texture, preservatives. -
Crystal Structure of Methyl 10-(Pyridin-4-Yl)-Anthracene-9
Z. Kristallogr. NCS 2018; 233(3): 441–443 Xiang Huang and Da-Bin Shi* Crystal structure of methyl 10-(pyridin-4-yl)- anthracene-9-carboxylate, C21H15NO2 Table 1: Data collection and handling. Crystal: Block, colorless Size: 0.30 × 0.20 × 0.10 mm Wavelength: Mo Kα radiation (0.71073 Å) µ: 0.09 mm−1 Diffractometer, scan mode: Bruker SMART, φ and ω-scans θmax, completeness: 27.6°, >99% N(hkl)measured, N(hkl)unique, Rint: 9199, 3516, 0.027 Criterion for Iobs, N(hkl)gt: Iobs > 2 σ(Iobs), 2700 N(param)refined: 218 Programs: Bruker programs [1], SHELX [2, 3] before stirring for 2 h at 65 °C. Crude 10-bromo-anthracene- 9-carboxylic acid was precipitated by adding the acetic acid solution to 800 mL of ice/water slush, followed by suc- https://doi.org/10.1515/ncrs-2017-0334 tion filtration. The residue on the filter was dissolved in Received October 31, 2017; accepted February 20, 2018; available 500 mL of a 5% aquaeus solution of K2CO3 followed by online March 6, 2018 gravity filtration to remove undissolved side products such as 9,10-dibromoanthracene. The filtrate was acidified with Abstract concentrated HCl to precipitate crude 10-bromo-anthracene- Aba a = C21H15NO2, orthorhombic, 2 (no. 41), 22.149(2) Å, 9-carboxylic acid, which was recrystallized from 100 mL b = c = V = 3 Z = 13.2899(12) Å, 10.6679(10) Å, 3140.2(5) Å , 8, ethanol to yield 5.76 g of yellow needles. R F = wR F2 = T = gt( ) 0.0418, ref( ) 0.0953, 296(2) K. -
ECO-Ssls for Pahs
Ecological Soil Screening Levels for Polycyclic Aromatic Hydrocarbons (PAHs) Interim Final OSWER Directive 9285.7-78 U.S. Environmental Protection Agency Office of Solid Waste and Emergency Response 1200 Pennsylvania Avenue, N.W. Washington, DC 20460 June 2007 This page intentionally left blank TABLE OF CONTENTS 1.0 INTRODUCTION .......................................................1 2.0 SUMMARY OF ECO-SSLs FOR PAHs......................................1 3.0 ECO-SSL FOR TERRESTRIAL PLANTS....................................4 5.0 ECO-SSL FOR AVIAN WILDLIFE.........................................8 6.0 ECO-SSL FOR MAMMALIAN WILDLIFE..................................8 6.1 Mammalian TRV ...................................................8 6.2 Estimation of Dose and Calculation of the Eco-SSL ........................9 7.0 REFERENCES .........................................................16 7.1 General PAH References ............................................16 7.2 References Used for Derivation of Plant and Soil Invertebrate Eco-SSLs ......17 7.3 References Rejected for Use in Derivation of Plant and Soil Invertebrate Eco-SSLs ...............................................................18 7.4 References Used in Derivation of Wildlife TRVs .........................25 7.5 References Rejected for Use in Derivation of Wildlife TRV ................28 i LIST OF TABLES Table 2.1 PAH Eco-SSLs (mg/kg dry weight in soil) ..............................4 Table 3.1 Plant Toxicity Data - PAHs ..........................................5 Table 4.1 -
Polycyclic Aromatic Hydrocarbon Migration from Creosote-Treated Railway Ties Into Ballast and Adjacent Wetlands
United States In cooperation Department of with the Agriculture Polycyclic Aromatic United States Forest Service Department of Transportation Hydrocarbon Migration Forest Products Federal Laboratory Highway Administration From Creosote-Treated Research Paper FPL−RP−617 Railway Ties Into Ballast and Adjacent Wetlands Kenneth M. Brooks Abstract from the weathered ties at this time. No significant PAH loss was observed from ties during the second summer. A Occasionally, creosote-treated railroad ties need to be small portion of PAH appeared to move vertically down into replaced, sometimes in sensitive environments such as the ballast to approximately 60 cm. Small amounts of PAH wetlands. To help determine if this is detrimental to the may have migrated from the ballast into adjacent wetlands surrounding environment, more information is needed on during the second summer, but these amounts were not the extent and pattern of creosote, or more specifically poly- statistically significant. These results suggest that it is rea- cyclic aromatic hydrocarbon (PAH), migration from railroad sonable to expect a detectable migration of creosote-derived ties and what effects this would have on the surrounding PAH from newly treated railway ties into supporting ballast environment. This study is a report on PAH level testing during their first exposure to hot summer weather. The PAH done in a simulated wetland mesocosm. Both newly treated rapidly disappeared from the ballast during the fall and and weathered creosote-treated railroad ties were placed in winter following this initial loss. Then statistically insignifi- the simulated wetland. As a control, untreated ties were also cant vertical and horizontal migration of these PAH suggests placed in the mesocosm. -
Safeguards Benzopyrene Contamination in Korean
SAFEGUARDS SGS CONSUMER TESTING SERVICES FOOD NO. 187/12 NOV 2012 BENZOPYRENE CONTAMINATION IN KOREAN INSTANT NOODLE On 25 Oct 2012, Korea Food and Drug Administration (KFDA) recalled six instant noodle products from the nation’s largest ramen maker in South Korea because these products were found to be tainted with benzo(a) pyrene, which is a known carcinogen.1 Several countries, including Philippines, Thailand, Taiwan and China, have been alerted to this and as a precaution, have removed these products from their shelves. Benzo(a)pyrene belongs to the group of polycyclic aromatic hydrocarbons (PAHs). Most PAHs derive from incomplete burning of carbon containing materials such as petroleum fuels, wood, and garbage. The occurrence of PAHs in foods is mainly caused by environmental contamination (water, air and soil), food processing (direct drying and heating), and packaging materials. PAHs have been found in different food products, such as dairy products, vegetables, fruits, oil, coffee, tea, cereals, smoked meat, seafood products, ingredients for food formulation, seasoning, and instant noodles. announcement of the test results and the recall order because the levels of In June, the KFDA conducted tests on benzopyrene found in the noodle products in June were minuscule and not harmful, 30 instant noodle products sold in the South Korean agency reported. However, the KFDA issued the recall order after South Korea and found that six its commissioner Lee Hee-sung was pressed on the matter during a legislative products contained benzopyrene, with question-and-answer, the report indicated.2 one product containing the highest level of 4.7 parts per billion (µg/kg). -
Polycyclic Aromatic Hydrocarbon Structure Index
NIST Special Publication 922 Polycyclic Aromatic Hydrocarbon Structure Index Lane C. Sander and Stephen A. Wise Chemical Science and Technology Laboratory National Institute of Standards and Technology Gaithersburg, MD 20899-0001 December 1997 revised August 2020 U.S. Department of Commerce William M. Daley, Secretary Technology Administration Gary R. Bachula, Acting Under Secretary for Technology National Institute of Standards and Technology Raymond G. Kammer, Director Polycyclic Aromatic Hydrocarbon Structure Index Lane C. Sander and Stephen A. Wise Chemical Science and Technology Laboratory National Institute of Standards and Technology Gaithersburg, MD 20899 This tabulation is presented as an aid in the identification of the chemical structures of polycyclic aromatic hydrocarbons (PAHs). The Structure Index consists of two parts: (1) a cross index of named PAHs listed in alphabetical order, and (2) chemical structures including ring numbering, name(s), Chemical Abstract Service (CAS) Registry numbers, chemical formulas, molecular weights, and length-to-breadth ratios (L/B) and shape descriptors of PAHs listed in order of increasing molecular weight. Where possible, synonyms (including those employing alternate and/or obsolete naming conventions) have been included. Synonyms used in the Structure Index were compiled from a variety of sources including “Polynuclear Aromatic Hydrocarbons Nomenclature Guide,” by Loening, et al. [1], “Analytical Chemistry of Polycyclic Aromatic Compounds,” by Lee et al. [2], “Calculated Molecular Properties of Polycyclic Aromatic Hydrocarbons,” by Hites and Simonsick [3], “Handbook of Polycyclic Hydrocarbons,” by J. R. Dias [4], “The Ring Index,” by Patterson and Capell [5], “CAS 12th Collective Index,” [6] and “Aldrich Structure Index” [7]. In this publication the IUPAC preferred name is shown in large or bold type. -
Plant Phenolics: Bioavailability As a Key Determinant of Their Potential Health-Promoting Applications
antioxidants Review Plant Phenolics: Bioavailability as a Key Determinant of Their Potential Health-Promoting Applications Patricia Cosme , Ana B. Rodríguez, Javier Espino * and María Garrido * Neuroimmunophysiology and Chrononutrition Research Group, Department of Physiology, Faculty of Science, University of Extremadura, 06006 Badajoz, Spain; [email protected] (P.C.); [email protected] (A.B.R.) * Correspondence: [email protected] (J.E.); [email protected] (M.G.); Tel.: +34-92-428-9796 (J.E. & M.G.) Received: 22 October 2020; Accepted: 7 December 2020; Published: 12 December 2020 Abstract: Phenolic compounds are secondary metabolites widely spread throughout the plant kingdom that can be categorized as flavonoids and non-flavonoids. Interest in phenolic compounds has dramatically increased during the last decade due to their biological effects and promising therapeutic applications. In this review, we discuss the importance of phenolic compounds’ bioavailability to accomplish their physiological functions, and highlight main factors affecting such parameter throughout metabolism of phenolics, from absorption to excretion. Besides, we give an updated overview of the health benefits of phenolic compounds, which are mainly linked to both their direct (e.g., free-radical scavenging ability) and indirect (e.g., by stimulating activity of antioxidant enzymes) antioxidant properties. Such antioxidant actions reportedly help them to prevent chronic and oxidative stress-related disorders such as cancer, cardiovascular and neurodegenerative diseases, among others. Last, we comment on development of cutting-edge delivery systems intended to improve bioavailability and enhance stability of phenolic compounds in the human body. Keywords: antioxidant activity; bioavailability; flavonoids; health benefits; phenolic compounds 1. Introduction Phenolic compounds are secondary metabolites widely spread throughout the plant kingdom with around 8000 different phenolic structures [1]. -
Metabolism of Non-Growing Cells and Their Application in Biotransformation
Preprints (www.preprints.org) | NOT PEER-REVIEWED | Posted: 17 July 2020 doi:10.20944/preprints202007.0402.v1 Metabolism of non-growing cells and their application in biotransformation Wenfa Ng Department of Chemical and Biomolecular Engineering, National University of Singapore, Email: [email protected] Abstract Growing cells is the typical mode of operation in many aspects of biotechnology and metabolic engineering. This comes about due to cell growth processes creating a driving force that pull metabolic flux along different metabolic pathways, that indirectly help move substrate to product. But, there is an alternative mode of operation that uses resting (non-growing) cells to achieve similar or even higher productivities. In general, resting cells are provided with carbon substrates for biocatalytic reactions but starved of nitrogen or phosphorus. Such resting cells have been usefully employed in many forms of biocatalysis and biotransformation, with or without cofactor regeneration. However, much remains unknown about the transcriptome and metabolome of resting cells in biotransformation settings. This short writeup provides the backdrop of resting cells in biocatalysis, documents their use in biotransformation with application examples, and identifies research gaps that could be filled with contemporary RNA- seq and mass spectrometry proteomics technology. Overall, utility of resting cells in biocatalysis and the extant knowledge gap in their fundamental physiology are highlighted in this resource. Keywords: resting cells, biocatalysis, cofactor regeneration, transcriptome, biotransformations, Subject areas: biochemistry, biotechnology, bioinformatics, systems biology, molecular biology, Non-growing (resting) cells in biotransformation Biotransformations sought the use of enzymes and whole cells for the conversion of substrates into desired products. Typically, whole cell biocatalysts are used given problems with instability and purification of pure enzymes. -
Estimation of Enthalpy of Bio-Oil Vapor and Heat Required For
Edinburgh Research Explorer Estimation of Enthalpy of Bio-Oil Vapor and Heat Required for Pyrolysis of Biomass Citation for published version: Yang, H, Kudo, S, Kuo, H-P, Norinaga, K, Mori, A, Masek, O & Hayashi, J 2013, 'Estimation of Enthalpy of Bio-Oil Vapor and Heat Required for Pyrolysis of Biomass', Energy & Fuels, vol. 27, no. 5, pp. 2675-2686. https://doi.org/10.1021/ef400199z Digital Object Identifier (DOI): 10.1021/ef400199z Link: Link to publication record in Edinburgh Research Explorer Document Version: Early version, also known as pre-print Published In: Energy & Fuels General rights Copyright for the publications made accessible via the Edinburgh Research Explorer is retained by the author(s) and / or other copyright owners and it is a condition of accessing these publications that users recognise and abide by the legal requirements associated with these rights. Take down policy The University of Edinburgh has made every reasonable effort to ensure that Edinburgh Research Explorer content complies with UK legislation. If you believe that the public display of this file breaches copyright please contact [email protected] providing details, and we will remove access to the work immediately and investigate your claim. Download date: 04. Oct. 2021 Estimation of Enthalpy of Bio-oil Vapor and Heat Required for Pyrolysis of Biomass Hua Yang,† Shinji Kudo,§ Hsiu-Po Kuo,‡ Koyo Norinaga, ξ Aska Mori, ξ Ondřej Mašek,|| and Jun-ichiro Hayashi †, ξ, §, * †Interdisciplinary Graduate School of Engineering Sciences, Kyushu University,