Water solubilities of polynuclear aromatic and heteroaromatic. Pahs generated from these sources can bind to or form small particles in the air. Examination of the sources of polycyclic aromatic hydrocarbon. View enhanced pdf access article on wiley online library html view download pdf for offline viewing. Polynuclear aromatic hydrocarbon molecules contain only carbon and hydrogen atoms. Chemical characterization of polynuclear aromatic hydrocarbon. Homogeneous metal catalysis for conversion between aromatic and saturated compounds. Niosh manual of analytical methods nmam, fourth edition, 81594 polynuclear aromatic hydrocarbons by gc. Organic chemistry ii chem 252 chapter 14 aromatic compounds. Most of the pahs with low vapour pressure in the air are adsorbed on particles. Ocr chemistry a aromatic compounds page 1 aromatic compounds naming aromatic compounds contain one or more benzene rings while aliphatic compounds do not contain benzene rings. Intermolecular potential calculations for polynuclear. In organic chemistry, aromaticity is a property of cyclic ringshaped, planar flat structures with a ring of resonance bonds that gives increased stability compared to other geometric or connective arrangements with the same set of atoms. Analysis of polynuclear aromatic compounds using laser.
Substitution at the benzene nucleus occurs by halogenation acid catalyst, nitration, sulfonation, and the friedelcrafts reaction. Polynuclear aromatic hydrocarbons cameo chemicals noaa. Nitrogen oxides are a group of seven gases and compounds composed of nitrogen and oxygen, sometimes collectively known as nox gases. Apr 24, 2016 polycyclic aromatic hydrocarbons pahs are widely distributed and relocated in the environment as a result of the incomplete combustion of organic matter.
Extract polynuclear aromatic hydrocarbons from water, using solid phase extraction disks envidisk solid phase extraction disks are a porous glass fiber matrix containing c8 or c18modified silica. Composition and ingredient information there are no additional ingredients present which, within the current knowledge of the supplier and in the concentrations applicable, are classified as hazardous to health or the environment and hence require reporting in this section. Heterocyclic aromatic compounds 26 heterocyclic compounds have an element other than carbon in the ring example of aromatic heterocyclic compounds are shown below numbering always starts at the heteroatom pyridine has an sp 2 hybridized nitrogen the p orbital on nitrogen is part of the aromatic. Method 5506, issue 3, dated 15 january 1998 page 4 of 9 niosh manual of analytical methods nmam, fourth edition c w w f w b b b f b b v, mgm3.
The overwhelming majority of aromatic compounds are compounds of carbon, but they need not be hydrocarbons. Minnesota pollution control agency hans neve kelly miller pdf only subject. The exponential growth of their chemistry has been made possible by the advent of xray crystallography and many other spectroscopic techniques. Polycyclic aromatic hydrocarbons are potentially mutagenic compounds widely occurring in natural media such as soils, atmosphere, sediments and plants edwards, 1983, sims and overcash, 1983, baek.
The role of aromatic ring number in reaction kinetics and product distribution. Polycyclic aromatic hydrocarbons pahs are widely distributed and relocated in the environment as a result of the incomplete combustion of organic matter. Standard test method for determination of the aromatic. Method 5515, issue 2, dated 15 august 1994 page 6 of 7 table 1. Arbabi 1department of pharmaceutical chemistry, university of lagos, nigeria 2department of environmental health engineering, school of health, shahrekord university of medical sciences, shahrekord, iran. Pdf analytical methods for polycyclic aromatic hydrocarbons. A few examples of aromatic hydrocarbons are provided below. Owing to the above situation, even the thousands of clusters and polynuclear compounds, which have been so far individuated and characterized, represent only the. Slivon the objective of this study was to characterize.
Concentrations of polynuclear aromatic hydrocarbons and. Polycyclic aromatic hydrocarbons pahs, also polyaromatic hydrocarbons or polynuclear aromatic hydrocarbons are hydrocarbons organic compounds containing only carbon and hydrogenthat are composed of multiple aromatic rings organic rings in which the electrons are delocalized. Pah is even present in some of our own household products such. Presents accounts of current research in polynuclear aromatic compounds, showing examples of studies both of pure compounds and of complex, fossil fuel related mixtures. Next we consider a class of hydrocarbons with molecular formulas like those of unsaturated hydrocarbons, but which, unlike the alkenes, do not readily undergo addition reactions. These compounds comprise a distinct class, called aromatic hydrocarbons. May 06, 2020 polycyclic aromatic hydrocarbons pahs formation in grilled meat productsanalysis and modeling with artificial neural networks. Extract polynuclear aromatic hydrocarbons from water, using. United states environmental protection agency environmental monitoring systems laboratory research triangle park, nc 27711 research and development epa600s487039 jan. Remediation division policy on analysis of carcinogenic. Polycyclic aromatic hydrocarbons aromatic compounds can have rings that share a set of carbon atoms fused rings compounds from fused benzene or aromatic heterocyclic rings are themselves aromatic naphthalene.
Pah is even present in some of our own household products such as mothballs, some shampoos and skin creams. The simplest such chemicals are naphthalene, having two aromatic rings, and the threering compounds anthracene. Method 5515, issue 2, dated 15 august 1994 page 3 of 7 sampling. Guidancepolicy for superfundrcravic program participants to use for. Another way to consider pahs is molecules made by fusing two or more benzene rings. Absorption spectra of dibenzofuran from 208 nm to 270 nm during a gc separation of pnas. The range of aromatics concentration to which this test method is applicable is from 1 to 75 mass %.
May 31, 2017 polycyclic aromatic hydrocarbons pahs are a group of more than 100 chemicals that are also called polynuclear aromatic hydrocarbons. They can react exothermically with bases and with diazo compounds. Polynuclear aromatic compounds pacs are byproducts of fuel burningwhich occur in coal, tar, and oil deposits. Polycyclic aromatic hydrocarbons pahs include hundreds of different chemicals that commonly occur as mixtures in the environment. Concentrations of polynuclear aromatic hydrocarbons and inorganic constituents in ambient surface soils, chicago, illinois. Polynuclear aromatic compounds pacs, pahs supelco air. Ultraviolet spectrometric detection for gas chromatography of. Analysis of polycyclic aromatic hydrocarbons in petroleum. Examination of the sources of polycyclic aromatic hydrocarbon pah in urban background soil. Iarc monographs on the evaluation of carcinogenic risks to. These rings share one or more sides and contain delocalized electrons.
Cannon, david graham, eric morton, and raymond bienert abstract polynuclear aromatic hydrocarbon pah compounds are ubiquitous in ambient surface. They have a relatively low solubility in water, but are highly lipophilic. Polycyclic aromatic hydrocarbons pahs polycyclic aromatic hydrocarbons pahs are a class of chemicals that occur naturally in coal, crude oil, and gasoline. Allcis catalytic hydrogenation of polynuclear aromatic hydrocarbons by group 5 metal aryl oxide compounds. Remediation division policy on analysis of carcinogenic polynuclear aromatic hydrocarbons cpah june 2011 author. Pdf on feb 7, 2018, abiodun olagoke adeniji and others published analytical methods for polycyclic aromatic hydrocarbons and their global trend of distribution in water and sediment. Jul 01, 2009 structural formulas of selected polycyclic aromatic hydrocarbons pahs. They are also referred to as arenes or aryl hydrocarbons. Polycyclic aromatic hydrocarbons pah are molecules made from carbon and hydrogen. A polynuclear aromatic hydrocarbon is a hydrocarbon made up of fused aromatic ring molecules. Limited toxicological data are available on pah mixtures.
Vigorous reactions, sometimes amounting to explosions, can result from the contact between aromatic hydrocarbons and strong oxidizing agents. It can be observed that all these compounds contain a benzene ring. Huckels rule is strictly for monocyclic aromatic compound, its application to polycyclic aromatic compounds is tenuous. Pacs are not only released from fossil fuels but also in cooked foods and other consumer goods, such as meat, from the high temperature grilling process as well as from incomplete combustion of other carboncontaining fuels such as tobacco, wood, coal, diesel fuel, edible fats, and. Allcis catalytic hydrogenation of polynuclear aromatic. Binding energies of homomolecular dimers rise rapidly with molecular size and asymptotically approach the experimentally established exfoliation energy for graphite of 5. Extract polynuclear aromatic hydrocarbons from water. Polycyclic aromatic hydrocarbons pahs are a group of more than 100 chemicals that are also called polynuclear aromatic hydrocarbons.
Recent advances on diversity oriented heterocycle synthesis of fused quinolines and its biological evaluation. Spent samples and unused standards are toxic waste. Aromatic hydrocarbons are circularly structured organic compounds that contain sigma bonds along with delocalized pi electrons. The following parameters can be determined by this method. Offers a thorough knowledge of aromatic chemistry through coverage of reduction, oxidation, and thermal reactionsincluding applications developed for both coal and petroleum materials. The term metal atom cluster was introduced in 1964 by f. They are ubiquitous pollutants formed from the combustion of. Oxidation of aromatic hydrocarbons with differing numbers of fused aromatic rings 25, have been studied in two solvent environments monophasic and biphasic using ruthenium. Polynuclear aromatic hydrocarbons in drinkingwater.
Astm d518615 standard test method for determination of. Clusters and polynuclear compounds have perhaps been regarded for a long time as fascinating chemical oddities. These cyclic hydrocarbons with alternating double and single carbon carbon. The use of this method to quantify these analytes is optional, and the reporting limits for some of these pah compounds in water are. Pahs are a class of diverse organic compounds containing two or more fused aromatic rings of carbon and hydrogen atoms. Calculations of intermolecular potentials are presented for homomolecular and heteromolecular clusters of 24 pericondensed pah spanning monomer masses ranging from 78 to 1830 da.
Polycyclic aromatic hydrocarbons pahs, also polyaromatic hydrocarbons or polynuclear aromatic hydrocarbons are hydrocarbonsorganic compounds containing only carbon and hydrogenthat are composed of multiple aromatic rings organic rings in which the electrons are delocalized. They also are produced when coal, oil, gas, wood, garbage, and tobacco are burned. Polycyclic aromatic hydrocarbons pahs formation in grilled meat productsanalysis and modeling with artificial neural networks. Epa project summary chemical characterization of polynuclear aromatic hydrocarbon degradation products from sampling artifacts j. Polynuclear hydrocarbons classification of polynuclear hydrocarbons polynuclear hydrocarbons may be divided into two groups, polynuclear hydrocarbons benzenoid non benzenoid isolated ring polynuclear hydrocarbons biphenyl diphenyl. Unless the purpose for the analysis can be served by reporting the sum of an unresolved pair, the liquid chromatographic approach must be used for these compounds. The first draft of polynuclear aromatic hydrocarbons in drinkingwater, background. Structural formulas of selected polycyclic aromatic hydrocarbons pahs. Aromatic compounds have substantial resonance stabilization benzene is aromatic. This report presents the initial results of efforts to extract additional chemical data from. In extractions of organic contaminants from 1 liter or more of water, these rigid disks provide faster flow rates and exhibit.
Although average descriptive parameters such as mo lecular weight range, aromaticity, and abundances of functional groups are. Nov 25, 2019 a polynuclear aromatic hydrocarbon is a hydrocarbon made up of fused aromatic ring molecules. Polynuclear aromatic hydrocarbon standard, part number 85006035 section 3. In extractions of organic contaminants from 1 liter or more of. This group includes benzene, alkylsubstituted benzenes, indans, tetralins, alkylsubstituted indans, and alkylsubstituted tetralins. Aromatic hydrocarbons are compounds that contain a benzene ring. The simplest such chemicals are naphthalene, having two. Introduction manmade sources, such as petrochemicals and the pyrolysis of organic compounds 1. Many pahs and their epoxides are highly toxic, mutagenic andor carcinogenic to microorganisms as well.
Organic compounds that are not aromatic are classified. Ultraviolet spectrometric detection for gas chromatography. Pah is comes into being when materials are burned, these materials include wood, oil, charcoal and tobacco. The basic benzene ring, c 6h 6 is commonly represented as a hexagon with a ring inside. The presence of polynuclear aromatic compounds pacs are a pacs m aquatic systems may be due to either point class of compounds which is ubiquitous in the envi sources or nonpoint sources. All additional pahs and related compounds extracted from the data files were lognormally. Aromatic molecules are very stable, and do not break apart easily to react with other substances. Another term for a compound containing a benzene ring is arene. Many pahs and their epoxides are highly toxic, mutagenic andor carcinogenic to microorganisms as well as to higher systems including humans. Astm d518615 standard test method for determination of the. Oxidation of polynuclear aromatic hydrocarbons using ruthenium. Obviously a multidimensional approach is needed here and, therefore, the online.
1209 217 202 981 1272 337 558 1382 1162 1162 1494 910 169 1026 141 1042 374 304 386 1342 890 369 558 1023 1362 1207 534 761 759 967 723 430 587 1266 659 1007 980 303 182 1093 612