United States
             Environmental Protection
             Agency	
Office of Pollution
Prevention and Toxics
Washington, DC 20460
June 1999
EPA 745-R-99-009
                    TOXICS RELEASE INVENTORY
        EZCMV    Guidance for Reporting Toxic Chemicals within the
                    Polycyclic Aromatic Compounds Category
      Section 313 of the Emergency Planning and Community Right-to-Know Act of 1986
(EPCRA) requires certain facilities manufacturing, processing, or otherwise using listed toxic
chemicals to report their environmental releases of such chemicals annually.  Beginning with the
1991 reporting year, such facilities also must report pollution prevention and recycling data for
such chemicals, pursuant to section 6607 of the Pollution Prevention Act, 42 U.S.C. 13106.
When enacted, EPCRA section 313 established an initial list of toxic chemicals that was
comprised of more than 300 chemicals and 20 chemical categories.  EPCRA section 313(d)
authorizes EPA to add chemicals to or delete chemicals from the list, and sets forth criteria for
these actions.
                                    CONTENTS

       Section 1.        Introduction	2
             1.1        Who Must Report	2
             1.2        Thresholds 	2
             1.3        Chemicals Within the Polycyclic Aromatic Compounds Category ... 3
             1.4        De Minimis Concentrations .	3

       Section 2.        Guidance for Reporting Chemicals within the Polycyclic Aromatic
                       Compounds Category	4
             2.1        Structural Features of Chemicals within the PACs Category 	4
             2.2        Formation of PACs  	5
             2.3        Formation of PACs from the Combustion of Fuels	6
             2.4        Formation of PACs from Major Industrial Processes  	7

       Section 3.        CAS Number List of Individual Chemicals within the Polycyclic
                       Aromatic Compounds Category 	14

       Section 4.        CAS Number List of Some Mixtures That Might Contain Chemicals
                       within the Polycyclic Aromatic Compounds Category	15

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                                                 Section 1. Introduction

          On November 30, 1994 EPA added 286 chemicals and chemical categories, which
   include 39 chemicals as part of two delineated categories, to the list of toxic chemicals
   subject to reporting under section 313 of the Emergency Planning and Community
   j^j^j-^^ Act of 1986 OBP"C'RA)V42 U'S.CT. 1 '16617' these additions are described at
   59 FR 61432, and are effective January 1, 1995 for reports due July 1, 1996. Six
   chemical categories (nicotine and salts, strychnine and salts, polycyclic aromatic
   (^oiripounds, wafer dissociable nitrate compounds, diisocyanates, an3 poly chlorinated
   alkanes) are included in these additions. At the time of the addition, EPA indicated that
   liilliiii! ii "i  i miii ii   mill , 'iiiliiliiiSir'ifi'a ,!""%" ..... i i w-   wW 5 ....... v ',  i,e ;.:p.ii'li ' ',' '.""in,, "1l '   " ' ,:. ' .11 .1:1,1:1* ""ni.1-1:. ., >,i!:::..:' -' 4 as '. : ....... .  . " ' ..... '..i,,. ,,:!i i , ",: ..... ..... . ,
   tfte Agency would develop, as appropriate, interpretations and guidance that the Agency
   determines $re necessary to facilitate accurate reporting for these categories. This
     c^eitfc^^                            polycyclic aromatic compounds category.
                     ...... Mi iJiit-ii ...... i '
    ection 1.1 Who ...... Must Report
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          A plant, factory, or other facility is subject to the provisions of EPCRA section
   313, if it meets al| three of the following criteria:
.';, iiiiiiiL'!	i	I	  i	111	            " 'i
                It is included in a covered Standard Industrial Classification (SIC) code as listed
                 in the following table; ana!
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Industrial Sector SIC code
Manufacturing
Metal mining
Coal mining
Electrical utilities
Treatment, storage, and disposal facilities
Solvent recovery services
Chemical distributors
Petroleum bulk terminals
20-39
10 (except 1011, 1081, and 1094)
12 (except 12411)
491 1, 4931, and 4939, limited to facilities that combust coal
and/or oil for the purpose of generating electricity for
distribution in commerce
4953, limited to RCRA Subtitle C permitted or interim status
facilities
7389, limited to facilities primarily engaged in solvent
recovery services on a contract or fee basis
5169
5171
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                     I      Jtljas 10 or more full-time employees (or the equivalent 20,000 hours per
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              It manufacturers, imports, processes, or otherwise uses any of the toxic
              chemicals listed on the EPCRA section 313 list in amounts greater than the
              "threshold" quantities specified below.

Section 1.2 Thresholds

       Thresholds are specified amounts of toxic chemicals used during the calendar year
that trigger reporting requirements.

       If a facility manufactures or imports any of the listed toxic chemicals, the threshold
quantity will be:

              25,000 pounds per toxic chemical or category over the calendar year.

       If a facility processes any of the listed toxic chemicals, the threshold quantity will be:

              25,000 pounds per toxic chemical or category over the calendar year.

       If a facility otherwise uses any of the listed toxic chemicals (without incorporating it

into any product or producing it at the facility), the threshold quantity is:

              10,000 pounds per toxic chemical or category over the calendar year.

       EPCRA section 313 requires threshold determinations for chemical categories to
be based on the total of all chemicals in the category manufactured, processed, or
otherwise used. For example, a facility that manufactures three members of a chemical
category would count the total amount of all three chemicals manufactured towards the
manufacturing threshold for that category.   When filing reports for chemical categories,
the releases are determined in the same manner as the thresholds.  One report is filed
for the category and all releases are  reported on this form.

Section 1.3 Chemicals Within the  Poly cyclic Aromatic Compounds Category

       EPA is providing lists of CAS numbers and chemical names to aid the regulated
community in determining whether  they need to report for the polycyclic aromatic
compounds category. The first list includes all individual chemicals within the polycyclic
aromatic compounds category.  If a  facility is manufacturing, processing, or otherwise
using a chemical which is on this list, they must report this chemical. The second list
includes chemical mixtures which might contain polycyclic aromatic compounds within the
category. If a facility is manufacturing, processing, or otherwise using a mixture which is
on this list and contains a polycyclic aromatic compound from the first list, they must
report the polycyclic aromatic component.  However, this list is not exhaustive.  If a
facility is manufacturing, processing, or otherwise using a mixture that contains a
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polycycltc aromatic compound from the first list, they must report the polycyclic aromatic
component, even if the mixture does not appear on the second list.

Section 1.4 De Minimis Concentrations

The polycyclic aromatic compounds category is subject to the 0.1 percent de
minimis concentration with the exception of dibenzo[a,e]fiuoranthene which is subject to
the one percent de minimis concentration.  Thus, mixtures that contain members of this
category equal to or in excess of the de minimis should be factored into threshold and release
determinations.

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Section 2. Guidance for Reporting Chemicals within the Polycyclic Aromatic Compounds
                                       Category

       Polycyclic aromatic compounds (PACs) are part of the broader class of chemicals
identified as polycyclic organic matter (POM). POM generally refers to matter identified in the
urban atmosphere, usually as suspended particles, produced from the incomplete combustion of
fuels. Polycyclic aromatic compounds, also referred to as polycyclic (and polynuclear) aromatic
hydrocarbons (PAHs), can be divided into two sub-classes: biaryls and condensed benzenoids.
Biaryl compounds are characterized structurally by two or more aromatic rings connected by a
single bond. Condensed benzenoid compounds, the larger of the two sub-classes, are
characterized structurally by at least two, usually three or more aromatic rings fused together
such that each pair of fused rings shares two carbons. Biphenyl, the simplest example of a biaryl
compound, is included on the initial EPCRA section 313 list. Naphthalene and anthracene, two
of the simplest examples of condensed benzenoid compounds, are also included on the initial
EPCRA section 313. The nineteen individual chemicals of the delineated polycyclic aromatic
compounds category added to the EPCRA section 313 list on November 30, 1994 are also
examples of condensed benzenoid compounds.

Section 2.1 Structural Features of Chemicals within the PACs Category

       Section 3 lists the nineteen individual chemicals of the polycyclic aromatic compounds
category added to the EPCRA section 313 list. Of the nineteen chemicals, ten are relatively
simple compounds structurally in that they are composed only of fused benzene rings (all contain
four or five rings). These ten compounds include benz[a]anthracene and a dimethyl derivative,
dibenz[a,h]anthracene, chrysene and a methyl derivative, benzo[a]pyrene, and four
dibenzopyrene isomers. PACs can also contain five-membered nonaromatic hydrocarbon rings
fused to six-membered aromatic hydrocarbon rings. Of the nineteen chemicals of the PACs
category, five are composed of one five-membered nonaromatic hydrocarbon ring fused to
aromatic hydrocarbon rings (the total number of benzene rings is four or five). These five
compounds include three benzofluoranthene isomers, dibenzo[a,e]fluoranthene, and an
indenopyrene isomer.

       PACs can contain atoms other than carbon and hydrogen that either are attached to a ring
or are part of a ring.  Aza-arenes are the neutral nitrogen analogs of PACs that contain only
carbon and hydrogen. PACs containing fused 5-membered nitrogen-containing rings such as
carbazole are aromatic.  PACs can also contain fused 6-membered nitrogen heterocycles such as
acridine.  Of the nineteen chemicals of the PACs category, three contain fused nitrogen
heterocycles. These three compounds include two dibenzacridine isomers and one
dibenzocarbazole isomer. Nitroarenes are PACs which contain one to two attached nitro groups.
One nitroarene, 1-nitropyrene, is included in the PACs category.

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Section 2.2 Formation of PACs

       The pyrolysis of hydrocarbon compounds results in the formation of various
carbon-based radical species which quickly combine to form a variety of compounds including
polycyclic aromatic compounds. In general, PACs can be formed from any pyrolysis or
combustion process that involves the burning of organic compounds (those containing carbon
and hydrogen).

       Factors, Affecting the Quantity of PACs Generated from Pyrolysis and Combustion
Processes. A number of factors influence how much polycyclic aromatic material will be
generated from a given pyrolysis or combustion process. These include the pyrolysis or
combustion method used, method efficiency, temperature range (or maximum), temperature
duration, and material combusted or pyrolyzed. The number of processes used for industrial and
other technical purposes is enormous, and the temperature at which these processes operate can
Vary significantly.  Operating temperatures for industrial processes can be roughly categorized as
low (several hundred degrees Celsius), medium (up to  800 or 900 degrees Celsius), and high
(greater that 800 or 900 degrees Celsius). PACs are generated from processes operating in all
three of these temperature ranges, however, the higher temperature processes tend to generate
compounds that are higher in aromatic  content.  Incomplete or inefficient combustion processes
also tend to generate higher quantities of PACs.

       Both the temperature and the duration of the pyrolysis or combustion process will affect
what types of polycyclic aromatic compounds will be generated. Typically only the most
structurally stable PACs (those that are angular in structure such as phenanthrene and chrysene,
and to a certain extent, those that have clustered structures such as pyrene) will be generated in
appreciable quantities from high temperature or long duration combustion processes. PACs that
are the least stable structurally (those that are linear in structure such as anthracene and tetracene,
and those that are highly alkylated) may be generated initially from high temperature or long
duration combustion processes, but if formed, will most likely equilibrate to more stable
structures during these processes unless they are isolated or released immediately after being
formed (as fugitive emissions, for example). PACs of low structural stability are generated in
more appreciable quantities from low temperature or short duration combustion processes.

       Non-technical Sources of PACs.  Non-technical sources of PACs are those that are not
controlled by technological means  and  consist primarily of forest, brush, and grass fires.

       Technical Sources of PACs. Technical sources of PACs include those from industry
as well as from other technological activities. Technical sources of PACs can be roughly divided
into several categories including fuel combustion, industrial processes, and miscellaneous
sources.

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       Listed below are several categories of technical sources that generate PACs and several
specific sources within each category. The lists include the main sources that are known to
generate PACs or are suspected of generating PACs. The lists are by no means exhaustive.
Future data may disclose additional sources from either current or new technologies.

Section 2.3 Formation of PACs from the Combustion of Fuels

       Fuel combustion is a major source of the energy used in the United States for
transportation and heat and power generation and is a significant source of PAC emissions.
Sources of PAC emissions from the combustion of fuels for transportation purposes include the
following:

            gasoline powered engines (e.g. automobiles)
            diesel engines (e.g. trucks, buses, and construction equipment)
            two-cycle engines (e.g. outboard motors, and motorcycles, lawn mowers)

Key factors affecting the quantity of PAC emissions generated from the above sources
include the efficiency of the engine involved, the operating temperature of the engine,
and the fuel or fuel mixture used. Research begun in the late 1960s and continues today
to develop more efficient engines and fuel mixtures that generate less emissions.
Another source of PAC emissions that is associated with some forms of transportation
but is not part of the actual fuel combustion process is the generation of particulate
emissions from rubber tire wear.

       Sources of PAC emissions from the combustion of fuels for heat and power generation
include the use of following materials as fuels:

            coal
            oil
             gas
            wood
                                                     *
As in the combustion of fuels for transportation purposes, key factors affecting the
quantity of PAC emissions generated from the combustion of fuels for heat and power
generation include the efficiency of the combustion unit and the operating temperature
of the unit.  Unit type and combustion temperature can vary, significantly depending on
which material is used as the fuel. For each material that is used, unit type and
temperature will also vary significantly depending on whether the heat or power
generated is for industrial, municipal, or residential purposes.

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Section 2.4 Formation of PACs from Major Industrial Processes

       Several industrial processes are know to or are suspected of generating significant
quantities of PACs. Industrial sources of PACs include processes involved in the
manufacture of the following materials:

             synthetic fuels from coal processing operations
             synthetic fuels from petroleum refining
              synthetic fuels from feedstocks other than coal and petroleum
             products other than fuels from coal and petroleum feedstocks

The intent of most coal processing and petroleum refining operations is the conversion of crude
fossil fuels into synthetic fuels of higher commercial value.  In addition to coal and petroleum,
several other natural substances as well as a few synthetic materials are used minimally in the
manufacture of synthetic fuels (or are currently being investigated for this purpose). Subsequent
processing of by-products obtained from the manufacture of synthetic fuels (particularly those
manufactured from coal and petroleum) results in a variety of non-fuel products.

       PACs may be generated as emissions (usually particulate) from industrial processes or
may be contained in the intended commercial product or by-products. Process type and
temperature are key factors affecting the quantity of PACs generated. In addition, PACs may be
present in significant quantities  in the crude feedstocks (particularly crude petroleum feedstocks)
used in these industrial processes.

       Manufacture of Synthetic Fuels from Coal Processing Operations.  Although the
majority of the coal mined in the United States is used directly as a fuel, a significant quantity is
processed into refined solid, liquid, and gaseous fuels.  Mined coal and coal dust are natural
sources of PACs, however, PACs are known to be generated from several coal processing
operations and are suspected of being generated from others. Because of the potentially
significant variations in the many factors involved in coal processing operations (such as source
of coal, process design, unit efficiency, and process conditions including temperature and
pressure), most processing operations should be considered possible sources of PACs unless data
clearly shows otherwise.

        More than 100 specific coal processing operations have been developed. These processes
can be roughly categorized into four major areas: thermal decomposition, hydrogenation,
gasification, and extraction. Of the major coal processing operations developed, the thermal
decomposition method (including carbonization or pyrolysis) is the process that is most likely to
generate significant quantities of PACs.  Carbonization is used in the manufacture of coke, a fuel
and reductant used in blast furnaces in the iron and steel  industry.  By-products from
carbonization are typically gaseous in form and can be a significant source of fugitive PAC
emissions. Condensation and rigorous scrubbing of these gaseous by-products results in the
recovery of several mixtures of materials that include coal tars, light oils, ammonia liquor, and
gases. The light oils generated  from the carbonization process typically contain monocyclic
                                             8

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aromatics and crude naphthalene and may contain small amounts of low molecular weight
polycyclic aromatic compounds. The majority of the PACs generated from coal carbonization
are contained in the coal tar product. Other major components in coal tars include phenolics and
paraffins.

       The carbonization process generally involves destructive distillation of coal in a
coke oven operating at high temperatures (900-1400C). The mechanism of coal
decomposition is a complex process that is believed to occur via several stages.  The
initial stage of decomposition occurs at temperatures between 450 and 500 C. It is in
this temperature range that the radical species that eventually combine to form PACs are
generated. As heating continues, a partially polymerized tar is formed. This
intermediate material formed during the manufacture of coke is a complex mixture of
hundreds of hydrocarbon species including  PACs with 3 to 8 or more condensed aromatic
rings and an average molecular weight of approximately 300. During the last stage of
coal carbonization, the highly polymerized aromatic components that constitute  coke are
formed (the molecular weights of these components are typically greater than 3000).

       Medium temperature (700-900 C) and low temperature (up to 700 C) carbonization
processes, currently not nearly as common in the United States as the high temperature process,
yield different ratios of solid, liquid, and gaseous products. The high temperature process
typically produces the highest yield of coke and the lowest yield of coal tar. The relative ratio of
the components that constitute the coal tars produced by each process will also vary with
temperature. The low temperature process typically produces a tar (low temperature tar) that is
highest in paraffin and phenolic content whereas the high temperature process typically yields a
tar (high temperature or coke tar) that is highest in aromatic content.

       PACs may be formed from coal gasification, however, in most first and second
generation gasification processes, the oils and tar by-products typical to coal carbonization
processes are formed in insignificant quantities or are not formed at all.  One exception in coal
gasification processes is the Lurgi method in which oil and tar by-products are generated in
addition to the intended gasification product, synthesis gas (a mixture of primarily carbon
monoxide and hydrogen).  As in coal carbonization, PACs generated from the Lurgi method may
be contained in the oils but are most likely to be found in the crude tars. Analysis of the
components in Lurgi gasification oils and tars shows that these materials are very similar to low
temperature carbonization oils and tars. The quantity of polycyclic aromatic material found in
Lurgi gasification by-products, particularly the tar by-product, therefore should be less than the
quantity found in products and by-products obtained from higher temperature processes.

       PACs also may be formed from coal hydrogenation (liquification) processes,
however, this coal processing method is currently of minimal commercial use in the
United States. The products obtained from coal hydrogenation include gases, coal oil,
and residues. The intended product is an oil suitable for use as a commercial fuel. The
coal oil obtained from the process boils over a large temperature range (175-550C).

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Distillation of coal oil into light, medium, and heavy fractions results in material that can be
upgraded to oils suitable for commercial use as fuels. If PACs are formed from coal
hydrogenation, they most likely will be found in the medium and heavy distillation fractions of
the coal oil product and in the residues obtained from the hydrogenation. In comparison to the
three carbonization processes, coal hydrogenation is roughly analogous to the low temperature
carbonization with respect to process operating temperature. The maximum temperature reached
during both processes is relatively low, and the quantity of PACs subsequently formed therefore
should be less than the quantity formed from higher temperature processes.

      Manufacture of Synthetic Fuels from Petroleum Refining. Crude petroleum contains a
range of components that include gases (natural gas is occasionally included in this group),
liquids (including oils and tars), and solids (asphalt and bitumen are often included in this group).
The components found in crude oil are enormous in number and type. Major types of
compounds contained in crude oil include paraffins, aromatic compounds, and, to a lesser extent,
sulfur and nitrogen-containing compounds. Almost every known type of aromatic compound has
been found in petroleum including PACs with two to seven or more condensed aromatic rings. It
has been estimated that one-sixth of the components found in the crude oil distillation fraction
boiling from 370 to 535 C are PACs.

      In addition to being contained in crude petroleum, PACs are known to be generated from
several petroleum refining processes and are suspected of being generated from others. The
major refining processes are described below. Because of the potentially significant variations in
the many factors involved in petroleum refining processes (such as source of crude petroleum,
refinery design, unit efficiency, and process conditions including temperature and pressure), most
processes should be considered possible sources of PACs unless data clearly shows otherwise.

      The principle products obtained from petroleum refining are transportation fuels and
heating oils. The petroleum refining processes used to generate these products are enormous in
number and type but can be roughly categorized into three general areas. Primary distillation
separates crude petroleum into numerous fractions including light, medium, and heavy oils and
residues. Conversion processes (usually cracking) convert components in the distillates into
compounds of different molecular weight and boiling point.  Upgrading processes (typically
hydrotreating) further refine distillates into commercial products. PACs  contained in crude
petroleum may be found in the medium to heavy oils obtained from primary distillation, but are
most likely to be found in the residues. The residual fraction is usually vacuum distilled to
remove additional oil fractions. Vacuum bottoms may be used as fuel or asphalt or may be
converted to coke by thermal cracking. Medium and heavy oil fractions typically undergo
hydrocracking, steam cracking, or catalytic cracking. Petroleum tars, common by-products from
petroleum cracking, are similar to coal tars and can contain significant quantities of PACs. After
hydrotreating, final products from these cracking processes include gasoline, diesel and jet fuel,
and heating oil.
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       Hydrocracking processes convert high molecular weight compounds to lower boiling
materials. Hydrocracking also results in a decrease in the molecular weight of aromatic
compounds (catalytic and steam cracking do not).  Process conditions are similar to hydrotreating
but are generally more extreme (higher temperatures and pressures are used).  Products obtained
from hydrocracking processes include diesel and jet fuels and kerosene.  In catalytic cracking
processes, heavy distillates are converted to lower molecular weight compounds that have
boiling points in the range of gasoline and middle distillates. Process operating temperatures are
in the 480-510C range.  Catalytic cracking produces approximately half of the gasoline
consumed in the United States.  Steam cracking is a thermal process used to generate olefinic
compounds used in the manufacture of petrochemicals.  Process operating temperatures are
typically 800-850C.                                       ;

       During catalytic processes (including hydrocracking), the catalyst used becomes
deactivated by deposition of carbon on its active sites. The catalyst is regenerated by combustion
of the deposits at temperatures in the 500-700 C range.  During this regeneration process, PACs
are likely to be formed in significant quantities.

       Hydrotreating improves the quality of commercial products primarily by removing sulfur,
but also by removing nitrogen, oxygen, and metals. Hydrotreating residues or crude petroleum
will generate lower boiling materials of higher commercial value. Catalytic hydrotreating
typically results in higher selectivity and faster reaction rates than thermal hydrotreating. If the
feedstock used is crude petroleum or residual material, the catalytic process is often not possible,
especially if metal content is high, because of irreversible deactivation of the catalyst. Typical
operating temperatures for hydrotreating processes are in the 350-500C range.

       Although the general processes described above are the sources in the petroleum industry
that are most likely to generate significant quantities of PACs, other practices in the industry may
also generate PACs and should not be excluded. Flaring waste: gas from petroleum refineries, for
example, is a possible source of PAC emissions.

       Manufacture of Synthetic Fuels from Feedstocks Other Than Coal and Petroleum.
The major industrial processes used in the United States in the manufacture of synthetic fuels
(described above) use coal and crude petroleum as feedstocks and include petroleum cracking for
the production of fuels for transportation and heat and power generation, and coal carbonization
for the production of coke for the iron and steel industry. Minor industrial processes for
converting materials other than coal and petroleum to synthetic fuel products have also been
developed or are currently under investigation and include pyrolysis of the following materials:

             biomass
             oil shale
             tar sands
             wood and other cellulose-based materials
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             scrap material
             wastes

Although the products obtained from pyrolysis of these materials are used primarily as fuels,
other uses may also be possible. The processes used in the pyrolysis of these materials for fuels
are in general more controlled than the direct combustion of these and similar materials as fuels.
The quantity of PACs formed from these processes is, as in the coal and petroleum processes
described, dependent on the specific pyrolysis method used and the operating temperature of the
method.

       The pyrolysis of biomass, oil shale, and tar sands results in the formation of solid, liquid,
and gaseous products, however, these materials currently are not utilized in the commercial
manufacture of fuels  in the United States. A variety of processing methods operating in a broad
temperature range (450-900C) are used in the pyrolysis of biomass, oil shale, and tar sands and
include thermal decomposition or coking and, to a lesser extent, hydrogenation, gasification, and
extraction. PACs may be generated from the pyrolysis of these materials as emissions or may be
contained in the heavier liquid and solid products.

       The controlled pyrolysis of wood, and to a lesser extent, bagasse, typically yields a solid
char or charcoal and can be a source of PAC emissions. Process operating temperatures typically
reach 500 C.  Wood  tar is a possible by-product from both the combustion of wood as a fuel and
the pyrolysis of wood in the manufacture of charcoal.  Components in wood tar may include
PACs.

       Products obtained from the pyrolysis of various scrap and waste materials can be
solid, liquid, or gaseous in form and may be acceptable for direct use as fuels or may be
upgraded to more suitable material.  Scrap materials used include plastics and rubber.
Waste materials are usually from municipal sources (wood, paper, and some plastics) or
from agricultural sources  (crop residues such as bagasse, rice straw and hulls, grain stalks,
corn cobs, and grasses). PACs may be generated from the pyrolysis of these materials as
emissions or may be  contained in the heavier liquid and solid products.

       Manufacture of Products Other Than Fuels from Coal and Petroleum Feedstocks. By-
products generated from coal processing and petroleum refining are often used in crude form as a
fuel at the site in which they are produced.  The gaseous by-products from the carbonization of
coal, for example, were at one time used as a general gaseous fuel until the advent of natural gas.
Currently, the bulk of coke oven gas produced during carbonization is returned back to the coke
oven as a fuel source or is used for other industrial heating purposes within the same plant.

       By-products from the coal and petroleum industries more often are processed into
materials suitable for various commercial uses other than as fuels. Certain oil fractions obtained
from petroleum refining, for example, are further processed into their individual components or
into simple mixtures  for use as solvents or chemical feedstocks. Petrochemicals are important
commercial products and include various low molecular weight aliphatic and aromatic
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compounds. Light oils obtained from coal carbonization are similarly processed but contribute
minimally to the chemical feedstock market compared to the processing of petroleum oils for the
same purpose (other materials currently under investigation as sources of chemical feedstocks
include biomass, oil shale, and tar sands). As mentioned previously, the by-products obtained
from coal processing and petroleum refining that most likely contain PACs are the medium to
heavy oils, crude tars, and residues.

       Coal tars (particularly those obtained from low temperature carbonization) and petroleum
tars are suitable for direct use only as a crude fuel. Utilization of crude tars for this purpose is
typically not practiced in the United States.  A more common practice is to distill tars to separate
various liquid fractions from residues or pitch. Tar liquids can be further fractionated into
components that include monocyclic aromatics such as benzene, toluene, and xylene;
hydroxyl-substituted monocyclic aromatics such as phenols, cresols, and xylols; naphthalene;
and pyridine. Pitches can be further processed for use in asphalt roofing and road applications
(described below) or as binders for electrodes (particular^ those used in aluminum smelting).
Tars and pitches are also used in wood preservatives and in the manufacture of carbon black
(described below), tar-epoxy coatings (used primarily in marine applications such as on ships or
off-shore structures), and hydrocarbon resins (used in rubber, adhesives, inks, paints, coatings,
and flooring).

       Carbon black is used primarily in rubber reinforcement and to a lesser extent as a colorant
for inks,  paints, plastics, and paper. Carbon black is generated from the partial combustion or
thermal decomposition of hydrocarbons in the gas phase. Process operating temperatures are
typically high (1200-1600C).. Viscous oil and tar by-products obtained from petroleum refining
and coal  coking are commonly used as feedstocks in the manufacture of carbon black. These
feedstocks are typically high in aromatic content and include decant oil (from petroleum cracking
in gasoline production), residual petroleum tars (from steam pyrolysis of petroleum in ethylene
manufacture), and coal tars (from coal  carbonization). In addition to being likely components in
several of the feedstocks commonly used in the manufacture of carbon black, PACs may also be
generated from the partial combustion  and thermal decomposition processes.

       Although specific definitions exist for asphalt and bitumen, the definitions can vary, and
the terms are often used interchangeably.  Asphalt is generally defined as any material whose
predominant constituent is bitumen. Bitumen is generally defined as a dark solid, semi-solid, or
viscous material, natural or synthetic, that is composed primarily of high molecular weight
hydrocarbons and includes tars and pitches.  More specific definitions describe asphalt as only
naturally-occurring material (such as rock and lake asphalt; mineral content is high) and bitumen
as a product from crude oil (mineral content is low and hydrocarbon content is high).  For the
purpose of this document, the general definitions of asphalt and bitumen apply.
                                            13

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       As mentioned previously, PACs are possible components in the thermally degraded
materials (including coal and petroleum tars and pitches) that are commonly used in asphalt
roofing and road applications. PACs are also generated from several processes involved in these
applications.  PACs have been identified from the air-blowing of asphalt, a procedure used to
yield material with a higher softening point that is more suitable for roofing applications. Other
procedures used in the asphalt industry that may generate PACs include, for example, asphalt
hot-road mixing.
                                           14

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Section 3. CAS Number List of Individual Chemicals within the Polycyclic Aromatic
                                Compounds Category
      EPA is providing the following list of CAS numbers and chemical names to aid the
regulated community in determining whether they need to report for the polycyclic aromatic
compounds category.  If a facility is manufacturing, processing, or otherwise using a chemical
which is listed below, they must report this chemical.
Listing by CAS Number of Each Individual Chemical within the Polycyclic Aromatic
Compounds Category
Chemical Name
Benz[a]anthracene
Benzo[a]phenanthrene
Benzo[a]pyrene
Benzo[b]fluoranthene
Benzo[j]flouroanthene
Benzo[k]fluoranthene
Benzo[rst]pentaphene
Dibenz[a,h] acridine
Dibenz[a,j]acridine
Dibenzo[a,h]anthracene
Dibenzo[a,e]fluoranthene
Dibenzo[a,e]pyrene
Dibenzo[a,h]pyrene
Dibenzo[a,l]pyrene
7H-Dibenzo[c,g]carbazole
7, 12-Dimethyl-benz[a]anthracene
Indeno[l,2,3-cd]pyrene
5-Methylchrysene
1-Nitropyrene
CAS Number
56-55-3
218-01-9
50-32-8
205-99-2
205-82-3
207-08-9
189-55-9
226-36-8
224-42-0
53-70-3
5385-75-1
192-65-4
189-64-0
191-30-0
194-59-2
57-97-6
193-39-5
3697-24-3
5522-43-0
                                          15

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Section 4. CAS Number List of Some Mixtures That Might Contain Chemicals within
                      the Polycyclic Aromatic Compounds Category

       EPA is providing the following list of CAS numbers and chemical names for mixtures
which might contain polycyclic aromatic compounds within the category.  This list will aid the
regulated community in determining whether they need to report for the polycyclic aromatic
compounds category. If a facility is manufacturing, processing, or otherwise using a mixture
which is listed below and contains a polycyclic aromatic compound from the previous list of
individual chemicals, they must report the polycyclic aromatic component.  However, this list is
not exhaustive. If a facility is manufacturing, processing, or otherwise using a mixture that
contains a polycyclic aromatic compound from the previous list, they must report the polycyclic
aromatic component, even if the mixture does not appear on the following list. Threshold
calculations for the polycyclic aromatic compounds category should account only for the
percentage of the polycyclic aromatic component(s) contained in the mixture.

       CAS definitions are available for most of the mixtures in the following table. These
definitions are provided in an appendix with the CAS numbers and chemical names of the
mixtures.
Listing by CAS Number of Some Mixtures That Might Contain Polycyclic Aromatic Compounds within the Category1
Mixture Name
Aromatic hydrocarbons, polycyclic
Aromatic hydrocarbons, C20-28, polycyclic, mixed coal-tar pitch-polystyrene pyrolysis-derived
Aromatic hydrocarbons, C20-28, polycyclic, mixed coal-tar pitch-polyethylene pyrolysis-derived
Aromatic hydrocarbons, C20-28, polycyclic, mixed coal-tar pitch-polyethylene-polypropylene
pyrolysis-derived
Aromatic hydrocarbons, C20-28, polycyclic, mixed arom. oil-polystyrene pyrolysis-derived
Aromatic hydrocarbons, C20-28, polycyclic, mixed arom. oil-polyethylene pyrolysis-derived
Aromatic hydrocarbons, C20-28, polycyclic, mixed arom. oil-polyethylene-polypropylene pyrolysis-
derived
Aromatic hydrocarbons, polycyclic, from decompn. of solvent extd. coal tar pitch-2,4,6-
trinitrophenol-reaction products
Aromatic hydrocarbons, polycyclic, from decompn. of iodine-solvent extd. coal-tar pitch charge-
transfer complexes
Aromatic hydrocarbons, polycyclic, toluene dealkylation distn. residues
Aromatic hydrocarbons, polycyclic, cyclohexanone-ext. residues
Aromatic hydrocarbons, polycyclic, alkylnaphthalene-toluene thermal hydrodealkylation distn.
residues
Petroleum
CAS Number
130498-29-2
101794-76-7
101794-75-6
101794-74-5
101794-73-4
101794-72-3
101794-71-2
94113-85-6
94113-84-5
93762-97-1
68409-74-5
68333-90-4
8002-05-9
 It cannot be determined form the mixture name if a chemical from the category is actually contained in the
mixture.
                                          16

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Listing by CAS Number of Some Mixtures That Might Contain Polycyclic Aromatic Compounds within the Category1
Mixture Name
Anthracene oil
Coke (coal tar), low-temp., low-temp, gasification pitch, calcined
Tar bases,, coal, low-temp., crude :
Tar bases, coal liquefaction, heavy oil fraction
Extracts (coal), coal tar pitch solvent
Extracts (coal), coal tar pitch solvent, reaction products with 2,4,6-trinitrophenol
Extracts (coal), coal tar pitch solvent, reaction products with iodine
Extract residues (coal), liquefaction heavy acid, alk. ext.
Extract residues (coal), naphthalene oil acid, alk. ext.
Distillates (coal tar), low-temp., pitch
Distillates (coal tar), upper, fluorene-low
Distillates (coal tar), high-temp., heavy oils
Distillates (coal tar), gasification, pitch, full range
Distillates (coal tar), gasification, heavy oils, pyrene fraction
Distillates (coal tar), pitch, pyrene fraction
Distillates (coal tar), pitch, heavy oils .
Distillates (coal tar), pitch, pyrene fraction
Distillates (coal), liquefaction, heavy
Distillates (coal tar), heavy oils
Distillates (coal tar), upper, fluorene-rich
Distillates (coal tar), upper, fluorene-free
Pitch, coal tar, high-temp., heat-treated
Pitch, mixed brown-coal tar-ethylene manufg. pyrolysis oil distn.
Pitch, brown-coal tar
Pitch, coal tar, high-temp., secondary
Pitch, coal gasification tar, low-temp.
Residues, alkene-alkyne manuf. pyrolysis oil byproduct distn.
Residues, olefin manuf. pyrolysis oil distn.
Residues (coal tar), pitch distn.
CAS Number
90640-80-5
150339-33-6
141785-66-2
140203-34-5
130576-63-5
94113-98-1
94113-97-0
94113-96-9
94113-95-8
140413-63-4
140203-27-6
140203-21-0
140203-20-9
140203-19-6
91995-52-7
91995-51-6
91995-42-5
91995-25-4
90640-86-1
84989-11-7
84989-10-6
121575-60-8
100403-59-6
100403-58-5
94114-13-3
94114-12-2
93686-02-3
92062-01-6
92061-94-4
 1 It cannot be determined from the mixture name if a chemical from the category is actually contained in the
. mixture.
                                                   17

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Listing by CAS Number of Some Mixtures That Might Contain Polycyclic Aromatic Compounds within the Category1
Mixture Name
Residues (coal tar), anthracene oil distn.
Residues (coal), coke-oven gas-polycyclic arom. hydrocarbons reaction products distn.
Aromatic hydrocarbons, polycyclic, automobile scrap shredder waste pyrolysis products
Aromatic hydrocarbons, polycyclic, scrap cable pyrolysis
Polyamides, polyester-, wastes, pyrolyzed, pyrolysis oil
Polyamides, polyester-, wastes, pyrolyzed, pitch residue fraction
Polyamides, polyester-, wastes, pyrolyzed, heavy oil fraction
Hydrocarbon oils, arom,, mixed with polyethylene, pyrolyzed, middle oil fraction
Hydrocarbon oils, arom., mixed with polystyrene, pyrolyzed, middle oil fraction
Hydrocarbon oils, arom., mixed with polyethylene and polypropylene, pyrolyzed, middle oil fraction
CAS Number
92061-92-2
92061-88-6
94581-00-7
90989-45-0
100801-78-3
100801-77-2
100801-75-0
101227-14-9
101227-13-8
100801-64-7
It cannot be determined from the mixture name if a chemical from the category is actually contained in the mixture.
                                                  18

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                                     References

L     M.R. Guerin, "Energy Sources of Polycyclic Aromatic Hydrocarbons," Polycyclic
       Hydrocarbons and Cancer, Academic Press, Inc., New York, 1978, vol. 1, pages 3-42.

2.     J.P. Longwell, "The Formation of Polycyclic Aromatic Hydrocarbons by Combustion,"
       National Symposium (International) on Combustion, The Combustion Institute, 1982,
       pages 1339-1350.

3.     M. Blumer, "Polycyclic Aromatic Compounds in Nature," Scientific American, 1976, vol.
       234, pages 34-35.

4.     Particulate Polycyclic Organic Matter, National Academy of Sciences, Washington,
       D.C., 1972.                                      ;

5.     A. Streitwieser & C.H. Heathcock, Introduction to Organic Chemistry, Macmillan
       Publishing Co., Inc., New York, 1981, pages 1030-1056.

6.     Kirk-Othmer, Encyclopedia of Industrial Chemistry, 3rd edition, John Wiley & Sons, New
       York, 1980.
                                         19

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                                      Appendix

101794-76-7  Aromatic hydrocarbons, C20-28, polycyclic, mixed coal-tar pitch-polystyrene
             pyrolysis-derived

      Definition: A complex combination of hydrocarbons obtained from mixed coal tar
      pitch-polystyrene pyrolysis. Composed primarily of polycyclic aromatic hydrocarbons
      having carbon numbers predominantly in the range of C20 through C28 and having a
      softening point of 100C to 220C (212F to 428F) according to DIN 52025.

101794-75-6  Aromatic hydrocarbons, C20-28, polycyclic, mixed coal-tar
             pitch-polyethylene pyrolysis-derived

      Definition: A complex combination of hydrocarbons obtained from mixed coal tar
      pitch-polyethylene pyrolysis. Composed primarily of polycyclic aromatic hydrocarbons
      having carbon numbers predominantly in the range of C20 through C28 and having a
      softening point of 100C to 220C (212F to 428F) according to DIN 52025.

101794-74-5  Aromatic hydrocarbons, C20-28, polycyclic, mixed coal-tar pitch-polyethylene-
             polypropylene pyrolysis-derived

      Definition: A complex combination hydrocarbons obtained from mixed coal tar
      pitch-polyethylene-polypropylene pyrolysis. Composed primarily of polycyclic aromatic
      hydrocarbons having carbon numbers predominantly in the range of C20 through C28
      and having a softening point of 100C to 220C (212F to 428F) according to DIN
      52025.

101794-73-4  Aromatic hydrocarbons, C20-28, polycyclic, mixed arom. oil-polystyrene
             pyrolysis-derived

      Definition: A complex combination of hydrocarbons obtained from mixed
      aromatic oil-polystyrene pyrolysis. Composed primarily of polycyclic aromatic
      hydrocarbons having carbon numbers predominantly in the range of C20 through
      C28 and having a softening point of 30C to 140C (86F to 284F) according to
      DIN 52025.

101794-72-3  Aromatic hydrocarbons, C20-28, polycyclic, mixed arom. oil-polyethylene
             pyrolysis-derived

      Definition: A complex combination of hydrocarbons obtained from mixed aromatic
      oil-polyethylene pyrolysis. Composed, primarily of polycyclic aromatic hydrocarbons
      having carbon numbers predominantly in the range of C20 through C28 and having a
      softening point of 30C to  140C (86F to 284F) according to DIN 52025.

101794-71 -2  Aromatic hydrocarbons, C20-28, polycyclic, mixed arom.
             oil-polyethylene-polypropylene pyrolysis-derived
                                         20

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       Definition: A complex combination of hydrocarbons obtained from mixed aromatic
       oil-polyethylene-propylene pyrolysis. Composed primarily of polycyclic aromatic
       hydrocarbons having carbon numbers predominantly in the range of C20 through C28
       and having a softening point of 30C to 140C (86F to 184F) according to DIN 52025.

94113-85-6   Aromatic hydrocarbons, polycyclic, from decompn. of solvent extd. coal tar
             pitch-2,4,6-trinitrophenol-reaction products     ;

       Definition: A complex combination of organic compounds obtained by addition of a
       picric acid solution to the solvent extract of a bituminous coal tar pitch and
       decomposition of the precipitated pitch-picric acid reaction product with bases.
       Composed primarily of high molecular weight polycyclic aromatic compounds.

94113-84-5   Aromatic hydrocarbons, polycyclic, from decompn. of iodine-solvent extd.
             coal-tar pitch charge-transfer complexes

       Definition: A complex combination of organic compounds obtained by addition of
       iodine solution to the solvent extract of a bituminous coal tar pitch and decomposition of
       the precipitated pitch iodine reaction products. Composed primarily of high molecular
       weight polycyclic aromatic compounds.

93762-97-1   Aromatic hydrocarbons, polycyclic, toluene dealkylation distn. residues

       Definition:  A complex combination of hydrocarbons obtained from the distillation of
       products from the thermal hydrodealkylation of toluene. It consists predominantly of bi-
       and polynuclear aromatic hydrocarbons such as diphenyl, methyldiphenyl, fluorene, and
       phenanthrene.

68409-74-5  Aromatic hydrocarbons, polycyclic, cyclohexanone-ext. residues

       Definition:  A complex residuum from the cyclohexanone extraction of anthracene salts.
       It consists predominantly of polynuclear aromatic hydrocarbons such as anthracene.

68333-90-4  Aromatic hydrocarbons, polycyclic, alkylnaphthalene-toluene thermal
             hydrodealkylation distn. residues

       Definition:  The complex residuum from the distillation of products from the thermal
       hydrodealkylation of alkylnaphthalene and toluene. It consists predominantly of bi- and
       polynuclear  aromatic hydrocarbons such as naphthalenes, biphenyl, fluorene and
       phenanthrene.

8002-05-9    Petroleum

       Definition:  A complex combination of hydrocarbons. It consists predominantly of
       aliphatic, alcyclic and aromatic hydrocarbons. It may also contain small amounts of
       nitrogen, oxygen and sulfur compounds. This category .encompasses light, medium, and
       heavy petroleums, as well as the oils extracted from tar sands. Hydrocarbonaceous
                                           21

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       materials requiring major chemical changes for their recovery or conversion to petroleum
       refinery feedstocks such as crude shale oils, upgraded shale oils and liquid coal fuels are
       not included in this definition.

90640-80-5   Anthracene oil

       Definition: A complex combination of poly cyclic aromatic hydrocarbons obtained from
       coal tar having an approximate distillation range of 300C to 400C (572F to 752F).
       Composed primarily of phenanthrene, anthracene and carbazole.

141785-66-2  Tar bases, coal, low-temp., crude

       Definition: The reaction product obtained by neutralizing the acidic extract of
       alkali-washed low-temperature coal tar middle oil with an alkaline solution, such as
       aqueous sodium hydroxide, to obtain the free bases. Composed primarily of a complex
       mixture of aromatic nitrogen bases.

140203-34-5  Tar bases, coal liquefaction, heavy oil fraction

       Definition: The heavy oil obtained by the high pressure hydrogenation of bituminous
       coal is subjected to acid extraction and then neutralized. The crude bases thus obtained
       contain polynuclear nitrogen aromatics such as quinoline, acridine, and phenanthridine.

130576-63-5  Extracts (coal), coal tar pitch solvent

       Definition: Solvent extract of bituminous coal tar pitch. Composed primarily of
       polycyclic aromatic hydrocarbons.

94113-98-1   Extracts (coal), coal tar pitch solvent, reaction products with 2,4,6-trinitrophenol

       Definition: Insoluble reaction product obtained by addition of a picric acid solution to
       the solvent extract of a bituminous coal tar pitch.  Composed primarily of polycyclic
       aromatic hydrocarbons.

94113-97-0   Extracts (coal), coal tar pitch solvent, reaction products with iodine

       Definition: Extract obtained by adding an iodine solution to the solvent extract of a
       bituminous coal tar pitch. Composed primarily of polycyclic aromatic hydrocarbons.

94113-96-9   Extract residues (coal), liquefaction heavy acid, alk. ext.

       Definition: The neutral oil obtained by debasing and dephenolating the heavy oil from
       the high pressure hydrogenation of bituminous coal. Composed primarily of
       unsubstituted and alkyl-substituted aromatic polynuclear hydrocarbons that are partially
       hydrogenated and may contain heteroatoms.

94113-95-8   Extract residues (coal), naphthalene oil acid, alk. ext.
                                           22

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      Definition: The neutral oil obtained by debasing mid dephenolating the middle oil from
      the low temperature carbonization of bituminous coal.  Composed primarily of a mixture
      of mono- and polynuclear, substituted, and unsubstituted aromatic and naphthenie
      hydrocarbons and heterocycles as well as paraffinic hydrocarbons.

140413-63-4  Distillates (coal tar), low-temp., pitch

      Definition: The distillate obtained during the heat treatment of low temperature coal tar
      pitch having  an approximate distillation range of 100C to 400C (212F to 752F).
      Composed primarily of a complex mixture of aromatic compounds.

140203-27-6  Distillates (coal tar), upper, fluorene-low

      Definition: A complex combination of hydrocarbons obtained by the crystallization of
      the fractional distillates from tar oil. It consists of aromatic polycyclic hydrocarbons,
      primarily diphenyl, dibenzofuran and acenaphthene.

140203-21-0 Distillates (coal tar), high-temp., heavy oils

      Definition: The distillate from the fractional distillation of high-temperature coal tar
      having an approximate distillation range of 280C to 450C (536F to 842F).
      Composed primarily of tri- and polynuclear aromatic hydrocarbons and heterocyclic
      compounds.

140203-20-9  Distillates (coal tar), gasification, pitch, full range

      Definition: The distillate obtained during the heat treatment of pitch obtained from coal
      gasification tar having an approximate distillation range of 100C to 400C (212F to
      752F). Composed primarily of aromatic and other hydrocarbons, phenolic compounds
      and aromatic nitrogen compounds.

140203-19-6  Distillates (coal tar), gasification, heavy oils, pyrene fraction

      Definition: The distillate from the fractional distillation of coal gasification tar having  an
      approximate boiling range of 350C to 450C (662F to 842F). Composed primarily  of
      phenanthrene and anthracene homologs, tetranuclear aromatic hydrocarbons which may
      also contain  heteroatoms, high-boiling aliphatic and naphthenie hydrocarbons, and
      polynuclear phenols.

91995-52-7   Distillates (coal tar), pitch, pyrene fraction

      Definition:  The redistillate obtained from the fractional distillation of pitch distillate and
      boiling in the range of approximately 380C to 410C (716F to 770F). Composed
      primarily of tri- and polynuclear aromatic hydrocarbons and heterocyclic compounds.

91995-51 -6   Distillates (coal tar), pitch, heavy oils
                                           23

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       Definition: The distillate from the distillation of the pitch obtained from bituminous high
       temperature tar. Composed primarily of tri- and polynuclear aromatic hydrocarbons and
       boiling in the range of approximately 300C to 470C (572F to 878F). The product
       may also contain heteroatoms.

91995-42-5  Distillates (coal tar), heavy oils, pyrene fraction

       Definition: The redistillate obtained from the fractional distillation of pitch distillate
       boiling in the range of approximately 350C to 400C (662F to 752F). Consists
       predominantly of tri- and polynuclear aromatics and heterocyclic hydrocarbons.

91995-25-4  Distillates (coal), liquefaction, heavy

       Definition: The heavy oil obtained by distillation in the range of approximately 300C to
       550C (572F to 1022F) of coal oil from the catalytic hydrogenation of coal and coal-
       derived products.  Composed primarily of polynuclear aromatics and naphmenes. The
       product contains sulfur, oxygen and nitrogen compounds.

90640-86-1   Distillates (coal tar), heavy oils

       Definition: The distillate from the fractional distillation of coal tar having an
       approximate distillation range  of 30QC to 400C (572F to 752F). Composed primarily
       of tri- and polynuclear aromatic hydrocarbons and heterocyclic compounds.

84989-11 -7  Distillates (coal tar), upper, fluorene-rich

       Definition: A complex combination of hydrocarbons obtained by the crystallization of
       the fractional distillates from coal tar. It consists of aromatic and polycyclic
       hydrocarbons, primarily fluorene and acenaphthene.

84989-10-6  Distillates (coal tar), upper, fluorene-free

       Definition: A complex combination of hydrocarbons obtained by the crystallization of
       tar oil. It consists of aromatic polycyclic hydrocarbons, primarily diphenyl, dibenzofuran
       and acenaphthene.

121575-60-8  Pitch, coal tar, high-ternp., heat-treated

       Definition: The heat treated residue from the distillation of high temperature coal tar. A
       black solid with an approximate softening point from 80C to 180C (176F to 356F).
       Composed primarily of a complex mixture of three or more membered condensed ring
       aromatic hydrocarbons.

100403-59-6  Pitch, mixed  brown-coal tar-emylene manufg. pyrolysis oil distn.

       Definition:  The residue from the joint distillation of brown coal tar and pyrolysis
       residual oil from ethylene plants. Composed primarily of polynuclear aromatic and
                                           24

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      naphthenic hydrocarbons which can be alkyl- and vinyl-substituted and can contain
      heteroatoms, paraffin hydrocarbons and high-boiling mono- and dinuclear phenols. It is a
      black solid with a softening point of 60C (140F) according to DIN 52025.

100403-58-5  Pitch, brown-coal tar

      Definition:  The residue from the distillation of brown coal tar formed by carbonization
      up to 1250C (2282F). Composed primarily of polynuclear aromatic and naphthenic
      hydrocarbons and heterocycles, paraffin hydrocarbons and high-boiling mono- and
      dinuclear phenols. It is a black solid with a softening point of 50C to 120C (122F to
      248 F) according to DIN 52025.

94114-13-3   Pitch, coal tar, high-temp., secondary

      Definition:  The residue obtained during the distillation of high boiling fractions from
      bituminous coal high temperature tar and/or pitch coke oil, with a softening point of 140
      to 170C (284F to 338F) according to DIN 52025.  Composed primarily of tri- and
      polynuclear aromatic compounds which also contain heteroatoms.

94114-12-2   Pitch, coal gasification tar, low-temp.

       Definition: The residue from the distillation of bituminus coal pressure gasification tar.
       A black solid with a softening point of greater than 60 C (140F) according to DIN
       52025 and composed primarily of a complex mixture of polynuclear aromatic and
       naphthenic hydrocarbons that may be alkyl substituted and may contain heteroatoms,
       high boiling aliphatic hydrocarbons and polynuclear phenols.

93686-02-3   Residues, alkene-alkyne manuf pyrolysis oil byproduct distn.

       Definition: A complex combination of hydrocarbons obtained as a residue from the
       distillation of residual oils that are obtained by the pyrolytic recovery of alkenes and
       alkynes from mineral oil products or natural gas. It consists predominantly of tri- and
       polynuclear aromatic and alkylaromatic hydrocarbons and has a softening point
       approximately 60C to 180C (140F to  356F) according to DIN 52025.

 92062-01-6   Residues, olefin manuf.pyrolysis oil distn.

       Definition: A complex combination of hydrocarbons obtained as a residue from the
       distillation of residual oils that are obtained by the pyrolytic recovery of alkenes and
       alkynes from petroleum products or natural gas. It consists predominantly of tri- and
       polynuclear aromatic and alkylaromatic hydrocarbons having a softening point of 20 C
       to 60C (68F to 140F) according to DIN 52025.

 92061 -94-4   Residues (coal tar), pitch distn.

       Definition: Residue from the fractional distillation of pitch distillate boiling in the range
       of approximately 400C to 470C (752F to 878F). Composed primarily of polynuclear
                                           25

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       aromatic hydrocarbons, and heterocyclic compounds.

 92061-92-2   Residues (coal tar), anthracene oil distn.

       Definition: The residue from the fraction distillation of crude anthracene boiling in the
       approximate range of 340C to 400C (644F to 752F). It consists predominantly of tri-
       and polynuclear aromatic and heterocyclic hydrocarbons.

 92061-88-6   Residues (coal), coke-oven gas-polycyclic arom. hydrocarbons reaction products
              distn.

       Definition:  The residue from the distillation of a complex reaction product, obtained by
       reaction of gases obtained by the dry distillation of bituminous coal with a distillate,
       consisting of di- and trinuclear aromatic hydrocarbons and their alkyl derivatives, with a
       softening point of 30C to 50C (86F to 122F). The residue consists predominantly of
       substituted aromatic di- and polynuclear hydrocarbons and sulfur-containing compounds.

 94581-00-7   Aromatic hydrocarbons, polycyclic, automobile scrap shredder waste pyrolysis
              products

       Definition: Pyrolysis product obtained from the thermal treatment of the organic portion
       of shredder waste arising from automobile scrap. Composed primarily of mono- to
       tetracyclic aromatic hydrocarbons and their alkyl derivatives.

90989-45-0   Aromatic hydrocarbons, polycyclic, scrap cable pyrolysis

       Definition: Fraction formed by the thermal treatment of scrap cables at about 700 C
       (1292F) with extensive exclusion of air.  Consists chiefly of mono- to tetranuclear
       aromatic hydrocarbons  and their alkyl derivatives.

100801 -78-3  Polyamides, polyester-, wastes, pyrolyzed, pyrolysis oil

       Definition: The oil obtained from the pyrolysis of textile wastes from a
       polyamide/polyester fiber mixture at 600C to 800C (1112F to 1472F).  It consists
       predominantly of benzene and naphthalene and their homologs, benzonitrile and other di-
       and polynuclear aromatic hydrocarbons.

100801 -77-2  Polyamides, polyester-, wastes, pyrolyzed, pitch residue fraction

       Definition: A residue from the distillation of textile waste pyrolysis oil.  It consists
       predominantly of polynuclear aromatic hydrocarbons boiling in a range above 350C
       (662 F).

100801-75-0  Polyamides, polyester-, wastes, pyrolyzed, heavy oil fraction

       Definition: A fraction from the distillation of textile waste pyrolysis oil. It  consists
       predominantly of benzonitrile, naphthalene and homologs and  other di- and polynuclear
                                           26

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      aromatic hydrocarbons boiling in the range of 200C and 350C (392F to 662F).

101227-14-9  Hydrocarbon oils, arom., mixed with polyethylene, pyrolyzed, middle oil
             fraction

      Definition: The oil obtained from the heat treatment of polyethylene with aromatic oils.
      It consists predominantly of naphthalene and its homologs, 1,3-diphenylpropane and
      other polynuclear aromatic hydrocarbons boiling in a range of approximately 200 C to
      400C (392F to 752F).

101227-13-8  Hydrocarbon oils, arom., mixed with polystyrene, pyrolyzed, middle oil
             fraction

      Definition: The oil obtained from the heat treatment of polystyrene with aromatic oils. It
      consists predominantly of naphthalene and its homologs, 1,3-diphenylpropane and other
      polynuclear aromatic hydrocarbons boiling in a range of approximately 200 C to 400 C
      (392F to 752F).

100801 -64-7  Hydrocarbon oils, arom., mixed with polyethylene and polypropylene, pyrolyzed,
             middle oil fraction

      Definition: The oil obtained from the heat treatment of a polyethylene/polypropylene
      mixture with aromatic oils.  It consists predominantly of naphthalene and its homologs,
       1,3-diphenylpropane and other polynuclear aromatic hydrocarbons boiling in a range of
      approximately 200C to 400C (392F to 752F).
                                          27

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