HIGH PRODUCTION VOLUME (HPV) CHEMICAL CHALLENGE PROGRAM

TEST PLAN

HEAVY FUEL OILS CATEGORY

Submitted to the US EPA

By

The Petroleum HPV Testing Group

www.petroleumhpv.org

Consortium Registration # 1100997

June 17, 2004June 17, 2004 Page 2 of 44 Heavy Fuel Oils Consortium Registration # 1100997

TABLE OF CONTENTS

Plain Language Summary 3

Description of The Heavy Fuel Oils Category 5

Category Rationale and Test Material Description 10

Evaluation of Existing Health Effects Data and Proposed Testing 11

Evaluation of Existing Physicochemical and Environmental Fate Data and Proposed Testing 20

Evaluation of Existing Ecotoxicit y Data and Proposed Testing 24

Matrix of Available Data and Proposed Testing 30

References 31

Appendices

Appendix A. CAS Numbers and Descriptions of Category Members 38 Appendix B. Links to Additional Resources 43 Appendix C. Robust Summary (separate document) 44

Figures

Figure 1. Heavy Fuel Oils Process Diagram 9 Figure 2. Refinery Stream Composition – Boiling Range vs. General Composition 10

Tables

Table 1. Composition of Representative Samples of the HFO Category 7 Table 2. Ecotoxicity Data for Heavy Fuel O il, Kerosene/Jet Fuel Oil, and Gas Oil. 26 Table 3: Matrix of Available Data and Proposed Testing 30June 17, 2004 Page 3 of 44 Heavy Fuel Oils Consortium Registration # 1100997

PLAIN LANGUAGE SUMMARY

The Heavy Fuel Oils (HFOs) category includes both fi nished products (residual fuels) and the primary refinery streams from which they are blended. Members of the heavy fuel oil category are a diverse group of substances encompassing hydrocarbons with a wide range of molecular weights, carbon numbers (C 7 to C 50 ) and boiling points (250 – 1112 °F (121 to 600 °C). In addition to petroleum hydrocarbons they contain heterocyclic compounds containing sulfur, nitrogen, and o xygen, and organo-metallic compounds. The residual fuels are low-grade fuels prim arily used in industrial boilers and other di rect source heating applications (e.g., blast furnaces) and as a principal fuel in marine applic ations. The finished heavy fuels (residual fuels) are products that consist primarily of the residuum of the refining process after virtua lly all of the higher-quality hydrocarbons have been distilled, cracked, or catalytically removed fr om crude oil feedstock. To produce a residual fuel of a specified viscosity, the high viscosity of the residual streams is reduced by adding a diluent (cutter stock) that is typically a lowe r quality distillate stream. The choice of the distillate cutter stock is itself variable and largely a function of availability at any given time within the refinery and the viscosity specifications of the product being manufactured. For instance, in refiner ies with catalytic cracking units, catalytically cracked cycle oils are common fuel diluents (CONCAWE, 1998). Because residual fuels are blended from a variety of different residual and distillate materials, the specifications for residual fuel oils are very general, with viscosity being the controlling specification. The exact blend used for a specific residual fuel is determined largely by the desired viscosity of the finished fuel and specifications set by ASTM (2002). As a result, the composition of residual fuel oils can vary widely and will depend on the re finery configuration, the crude oils being processed and the overall refinery demand.

The Testing Group is proposing to perform a repeat-dose/reproductive/developmental screening study (OECD 422) on a representative sample of a reformer residue. A representative sample of a residual fuel oil will be tested using the reproductive/development al screening protocol (OECD 421). In-vitro genotoxicity assays (modified Ames & chromosomal aberr ation) will also be performed on sa mples of an atmosp heric residue, atmospheric distillate, cracked distillate, re former residue and a residual fuel oil.

The environmental fate characteristics of the materials in this category are due in large part to the physicochemical parameters of the individual component hydroc arbons. Where physico-chemical data did not exist or were impractical to obtain, calculated physico-chemic al and environmental data for selected constituents of category members has been developed using the EPIWIN © computer model.

When released to the environment, the dispersion of heavy fuel oil depends upon the severity of the weathering elements. High-energy environments will tend to disperse substances more quickly than low energy environments. During weathering, low mo lecular weight fractions will dissolve in the water column or volatilize to the air, whereas intermediate fractions will float an d/or spread out on water or soil where they tend to form emulsions or adsorb to soil and sediment particles. The viscous high molecular weight components will agglomerate and float or sink depending upon the density of the substance. Volatile components are not expected to persist in the atmosphere due to their ca pacity to undergo direct and/or indirect photodegradation. Hydrocarbons are regarded as being inherently biodegradable, and the low molecular weight fraction that dissolves in water will rapidly biodegrade. The limited water solubility and bioavailability of the heavy fractions reduces their capacity for biodegradation. These substances will biodegrade, although at a much slower rate.

For the assessment of the ecotoxicity of heavy fuel oils , the category substances are considered as a single group, and the potential for any category member to elicit adverse effects in aquatic organisms is attributed to the solubility of the constituent hydrocarbons in that member. This is valid because petroleum hydrocarbons elicit effects through a common mode of toxicity termed nonpolar narcosis (van Wezel and Opperhuizen, 1995), which is produced by the soluble hydrocarbon fractions in aqueous preparations. Fuels having molecular weight hydrocarbons predominately higher than the solubility “c ut-off” for acute toxicity show no measurable acute toxicity (CONCAWE 2001). The solubility cut-off varies with the hydrocarbon struct ure; thus, for paraffinic hydrocarbons the solubility cut-off occurs at about C1 0, while for alkylbenzenes it is about C14 (CONCAWE, 2001). Other individual components contribute to toxicity , but as molecular weight increases, both solubility and toxicity declineJune 17, 2004 Page 4 of 44 Heavy Fuel Oils Consortium Registration # 1100997

Existing aquatic toxicity data show heavy fuel oil related refinery streams to have moderate to no aquatic toxicity depending upon species and test substance. Algae hav e exhibited a greater sensitivity than fish or invertebrates to heavy fuel oil exposure, and different subs tances have produced different toxicity in the same species. Because substances in the Heavy Fuel O il category include a wide range of molecular weight hydrocarbons, existing data may not represent the ecotoxicity of some category members based on their distillation and carbon number ranges. However, the Testing Group believes the combination of existing residual fuel oil ecotoxicity data and data on kerosene and gas oil streams sufficiently covers what would be expected for the ecotoxicity of all me mbers of the heavy fuel oil category. Kerosene and gas oils are composed of similar hydrocarbon constituents as in heavy fuel o ils and have similar molecular weights as the light components of category members with low initial boiling points. Therefore, because the light-end components of the heavy fuel category members are expected to be the most toxic components, the ecotoxicity of the kerosene and gas oils represent a conservative estimate of the ecotoxicity for those heavy fuel oil category members. No additional ecotoxicity testing of heavy fuel oil is proposed.June 17, 2004 Page 5 of 44 Heavy Fuel Oils Consortium Registration # 1100997

DESCRIPTION OF THE HEA VY FUEL OILS CATEGORY

The Heavy Fuel Oils (HFOs) category includes both fi nished products (residual fuels) and the primary refinery streams from which they are blended. The residual fuels are low-grade fuels primarily used in industrial boilers and other direct source heating applications (e.g., blast furn aces) and as a principal fuel in marine applications. The residual fuels are products that consist primarily of the residuum of the refining process after virtually all of the higher-quality hydroc arbons have been dist illed, cracked, or cata lytically removed from crude oil feedstock. Historically, fuel oils were based on residues from th e atmospheric column. However, the increasing demand for transportation fuels such as gasoline, kerosene and diesel has led to an increased value for the atmospheric

residue as a feedstock for vacuum distillation and for crac king processes. As a consequence, most heavy fuel oils are currently based on vacuum residues and residue s from thermal and catalytic cracking operations (CONCAWE, 1998). These high viscosity re sidual streams may in turn be “cut” with lower quality, lighter weight distillates to produce a finished residual fuel of a specifi ed viscosity. The choice of the distillate cutter stock is itself variable and largely a function of availability at any given time within the refinery and the viscosity specifications of the fuel being manufactured. While t he materials most frequently used as cutter stocks are included in this category, other streams may occasionally be used, e.g., kerosene and gas oils. These other

materials are characterized in other API HPV Test Plans. The exact blend used for a specific residual fuel is determined largely by the desired viscosity of the finished fuel and specifications (ASTM, 2002). Some of the refinery streams in the category that have lower visco sities and lower polyaromatic compound (PAC) levels have low-volume, specialty applications such as cutte r stock in cutback asphalt, synfuel binders and carbon electrode production.

Members of the heavy fuel oils category are a diverse gr oup of substances that encompass hydrocarbons with a wide range of molecular weights, with carbon numbers ranging from C 7 to C 50 and boiling points between 250 – 1112 °F (121 to 600 °C). However, “typical” heavy fuel oils are C 20 -C 50 with the low carbon numbers and boiling temperatures being associated with lighter weight “c utter” streams (CONCAWE, 1998). All the category members are complex mixtures, containing variable amounts of alkanes, cycloalkan es, aromatics, olefins, asphaltenes, and hetero-molecules containing sulfur, o xygen, nitrogen and organo-metals. Because they are complex mixtures composed of relatively high molecular weight compounds, the materials in this category are difficult to characterize in detail. Consequently, t hey are typically not defined by detailed compositional information but instead by process history, physical prope rties, and product use specifications (ASTM, 2003). Since viscosity is the controlling specification, and other limiting requirements - notably boiling point ranges - are unspecified, there is significant variation in the chemical composition of the resulting fuel products (Uhler, 2002; IARC, 1989).

Because the process history of a refinery stream deter mines its chemical composition, the Testing Group expects that streams that have und ergone similar processing will have similar physical/chemical/biologic properties and environmental fate and transport characteri stics. The refinery streams within the heavy fuels category can therefore be grouped into seven subcategorie s based on their process histories. As shown in Figure 1, the major processes used to produce the refiner y streams included in the heavy fuel oils category are:

Atmospheric distillation Heavy fuel oil related streams produce d by atmospheric distillation comprise fractions of cr ude oil separated by heating (650-700 degrees °F) at atmospheric pressu re. They include atmospheric distillates (heavy gas oils) and the heavier residual materials. The distillate HFO streams are similar to some of the refinery streams covered in the API HPV Gas Oils category, albeit of higher molecular weight. Some of these streams may be further hydrotreated or desulfurized to remove sulfur, nitrogen, and other impurities. Most atmospheric distillate s undergo further processing in order to convert them into higher value fuels (diesel, kerosene). However, a portion of the heavier distillate streams may be used as blending stocks to reduce the viscosity of the residual streams. The residual refinery streams comprise a heterogeneous group of poorly defined, viscous, high boiling hydrocarbon st reams that usually c ontain suspensions of resin/asphaltene complexes. These streams often have high levels of heterocyclic aromatic and naphthenic compounds. Varying percentages of sulfur, nitrogen, oxygen, and other elements are present as heterocyclic inclusions, primarily in the aromatics fraction. Th ese residual streams often have a PAC content over 5%, but the content can be much higher depending on the pr ocessing the stream has undergone. As shown inJune 17, 2004 Page 6 of 44 Heavy Fuel Oils Consortium Registration # 1100997

Figure 1, there are eight refinery streams in the heavy fuel oils category that are produced by atmospheric distillation (two distillate and six residual streams). S ee Appendix A for a more detailed description of each of

these streams.

Vacuum distillation The residuum from the atmospheric distillation unit is heated at higher temperatures to further separate heavier molecules. This is done under reduced pressu re to prevent thermal cracking. In addition to producing lube oils, various vacuum distillates (vacuum gas oils) and vacuum re sidues are produced. Similar to the atmospheric distillates, some of the vacuum distillates may be hydrot reated or desulfurized to remove sulfur, nitrogen, and other impurities. Most vacuum di stillates undergo further processing in order to convert them into higher value fuels (diesel, kerosene). Howe ver, a portion of the heavier vacuum distillate streams may be used as blending stocks to reduce the viscosit y of the residual streams. The vacuum residual refinery streams comprise a heterogeneous group of poorly defined, viscous, high boiling hydrocarbon streams that usually contain suspen sions of resin/asphaltene complexes. These streams often have high levels of heterocyclic aromatic and naphthenic compounds. Varying percentages of sulfur, nitrogen, oxygen, and other elements are present as heterocyclic inclusions, primarily in the aromatics fraction. These residual streams often have a PAC content over 5%, but the content can be much higher depending on the processing the stream has undergone. As shown in Fi gure 1, there are nine refinery streams in the heavy fuel oils category that are produced by vacuum dist illation (seven distillate and two residual streams). See Appendix A for a more detailed descript ion of each of these streams.

Cracking Many of the distillate and residual streams used to blend he avy fuel oils are derived from cracking processes. Cracking is a process that breaks (“cracks”) the h eavier, higher boiling petroleum streams produced by atmospheric or vacuum distillation into lighter molecular weight materi als such as gasoline, diesel fuel, jet fuel and kerosene. Often, after cracking, stream s may be hydrotreated (reduces nitrogen and aromatic content) or undergo desulfurization.

There are two basic types of cracki ng processes, those using heat and pres sure (thermal cracking) to break molecular bonds, and those us ing a catalyst (catalytic cracking) to facilitate the cracking process. Both thermal and catalytic cracking are used to produce refiner y streams that are used for blending heavy fuel oils.

Visbreaking, coking and steam cracking are types of ther mal cracking. In visbreaking, the heavy feedstock is heated under pressure to crack the molecules in the stream. Coking is a severe method of thermal cracking. In steam cracking, the hydrocarbon stream is dilu ted with steam and then briefly heated (>900 °C) in a furnace. Light hydrocarbon feeds produce streams rich in the lighter alkenes, including ethylene, propylene and butadiene. Heavier hydrocarbon feeds give some of these, but also give products rich in aromatic hydrocarbons. Petroleum pitch, sold as a product for various applications, is a high aromatic residual material produced from either thermal cracking or catalytic cracking.

Catalytic cracking and hydrocracking are two types of ca talytic cracking. Catalytic cracking is similar to thermal cracking except a catalyst fa cilitates conversion of the heavier to lighter products and requires less severe operating conditions than thermal cracking. Cata lytic cracking converts heavy paraffins to light paraffins and olefins, heavy naphthenes to light napht henes and olefins, and heavy aromatics to light aromatics, naphthenes and olefins. As noted above, petroleum pitch is a high aromatic residual material from either catalytic cracking or thermal cracking.

Hydrocracking is a combination of catalytic cr acking and hydrogenation, using high pressure, high temperature, a catalyst, and hydrogen. It is typically used for feedstocks that are difficult to process by either catalytic cracking or reforming. When the feedstock has a high paraffin content, the primary function of hydrogen is to prevent formation of PACs. Hy drocracking converts sulfur and nitrogen compounds to hydrogen sulfide and ammonia.

The Testing Group thinks the refinery streams produced by the various cracking processes can be considered as a single subcategory since they represent a continuum in the severity of the cracking process.June 17, 2004 Page 7 of 44 Heavy Fuel Oils Consortium Registration # 1100997

All the cracking processes produce refinery streams t hat are similar from a physical-chemical perspective, being differentiated from each other primarily by the ratio of their unsaturated and saturated hydrocarbon

content. While the ratio of the saturated and arom atic hydrocarbons may vary between subcategory members, the saturated and aromatic hydrocarbons species that make up t he subcategory members are similar. For instance, refinery streams that are pro duced by catalytic cracking (most severe) have high levels of aromatics. In contrast, hydrocracked (least severe) streams have relatively low amounts of aromatics, since hydrocracking introduces hydr ogen into the cracking process that results in saturation of aromatic compounds. As shown in Figure 1, there are eleven refinery streams in the heavy fuel oils category that are produced by cracking (five distillate and six residual streams). See Appendix A for a more detailed description of each of these streams.

Reforming Catalytic reforming employs a catalyst to facilitate t he structural rearrangement of hydrocarbon molecules in order to increase the aromatic content of a refinery stream, ultimately leading to a gasoline with a higher octane. During reforming, olefins are saturated to form paraffins, which are then converted to shorter paraffins, isoparaffins, and naphthenes. The naphthenes are converted to arom atics by dehydrogenation (Gary and Handwerk, 1994). As shown in Figure 1, t here are two refinery streams in the heavy fuel oils category that are produced as residues of reforming. See Appendix A for a more detailed description of each

of these streams.

Residual Fuel Oils In addition to the process streams discussed above, t he heavy fuel oil category also includes two blended

residual fuel oils. These two fuel oils are most oft en produced by blending any comb ination of the distillate and

residual streams contained in the sev en process subcategories, provided the finished fuel meets the appropriate product specifications. Less frequently, the residual fuels can be blended using residual streams from this category, but petroleum distillates (cutter stocks) covered in other API HPV Test Plans. See Appendix A for a more detailed description of each of these two residual fuel oils.

Analytical data for representative materials in this category are shown in Table 1.

Table 1. Composition of Representative Samples of the HFO Category

Endpoint Atmospheric

Residue Vacuum

Distillate Cracked

Distillate Cracked

Residue Residual Fuel

Oil

CAS No. 64741-45-3 64741-57-7 ) 64741-81-7 64741-62-4 68476-33-5 Specific gravity 0.9698 0.9285 0.9383 1.0725 0.8491

Refractive index 1.5132 1.515 1.5259 Too dark 1.6306

Distillation (°F)

IBP 531 548 411 395 340

End point 1041 1131 831 952 1239

Non-aromatics 32.18 40.03 49.6 41.7 55.8 Aromatics (wt %) 67.82 59.97 50.4 58.3 44.2

API, 1987;CONSCI 1992a,b; DataChem 1990

Composition of Heavy Fuel Oil Blending Streams While detailed compositional information is limited, gener al compositional information can be inferred from a refinery stream’s physical properties and the type of pr ocessing it has undergone. For instance, the higher the boiling temperature range of a stream, the higher the molecular weight of the oil’s component s, the higher the levels of PACs, polycycloparaffins and hetero-atoms (N, O, S, and metals) increase, and the lower the levels of paraffins (see Figure 2). Furthermore, since “cracking ” raises the olefin and aromatic content of refinery streams, streams that have been “crack ed” have higher olefin and aromatic hydrocarbon content than “straight run” streams that have undergone a limit ed amount of additional processing. For example, catalytically cracked clarified oil has been reported to contain 58% three to five ring aromatic hydrocarbons (IARC, 1989). Thus, aJune 17, 2004 Page 8 of 44 Heavy Fuel Oils Consortium Registration # 1100997

residual fuel blended using primarily catalytically crac ked or steam cracked components will have a higher PAC content (may approach 20%) than a fuel blended primarily of a non-cracked stream, i.e. heavy vacuum gas oil (CONCAWE, 1998). If on the other hand, the blending stocks ar e predominantly atmospheric or vacuum distillates or residues, the concentration of three to seven ring aromatic hydr ocarbons is likely to be of the order of 6-8% (IARC, 1989). The types and levels of PACs found in a specific fuel will depend on the processing the residual portion of the fuel has undergone, and the nature of the blending stream (“cutter” stock) that is used to adjust the viscosity of the finished fuel.Figure 1. HFO Process DiagramAtmosphericDistillationVacuumDistillationResidual64741-67-968478-13-7DistillateResidual64741-62-464741-75-964741-80-668187-58-668478-17-168783-13-168410-00-468783-08-4Reformer64741-45-364742-78-568333-22-268476-32-468607-30-770592-79-9DistillateResidualDistillateResidualCatalytic CrackingThermal CrackingCokingHydrocracking64741-61-364741-81-768333-26-668333-27-770955-17-864741-57-764742-59-264742-86-568955-27-170592-76-670592-77-770592-78-868512-62-970913-85-8Crude OilResidual FuelOils68476-33-568553-00-4lFigure 2. Re finer y Stream Compositi on – Boiling Rang e v s . General Comp osition



### Cut t e r St oc ks Heav y Fuel Oils

Speight, 1998

Links to additi onal re so urce s on refini ng pro c e s ses a n d pet role um-related glo s sa ries a r e p r e s e n ted in Appe ndix

B.

CATE G O R Y RATI O N A LE AN D TEST M A TERI AL DE SCRIPTIO N

With re gard to mammalia n toxicity, when analyzi ng the exis ting d a ta, propo sin g testing an d identifying po tential

test material s the Testing Grou p co nsi d ered the follo wing:

• The HF O cat egory con s ist s of finishe d prod uct s (res i dual fuel s) an d the prima r y refine ry strea m s from

whi c h they are blend ed;

• The refin e ry stream s in this catego ry that are blen ded t o prod uce finishe d heavy fuels can b e g r oup ed

into seven su bcate gori e s a c cord i ng to their process hi story;

• Refine ry stre ams withi n a pro c e ss sub c ategory a r e si milar from a p r ocess an d p h ysical/ch e mi cal

perspe c tive, and are expe cted to have simila r biologi c, environ me ntal fa te and tran spo r t ch aracteri stics;

• The ra nge of toxicity of the material s in e a ch p r o c e ss sub c ate gory can b e ch ara c teri zed by

cha r a c teri zin g rep r e s entati v e material s within ea ch subcatego ry;

• The toxicity of the finished prod uct s (Re s idu a l Fuel Oi ls) will fall wit h in the ran ge of toxicities e x hibited by the stream s blen ded to prod uce the finish ed fuel;

• Becau s e of compo s itional overlap s an d simila rities , ot her API HPV test pro g ram s involving gas oils,

arom atic extracts, jet fuel/kero s en e and asp halt will produ ce data th at will assist i n cha r a c teri zi ng the

materials in this category.

With re gard to ecotoxi c ity, whe n analy z ing the existin g data, the Testing G r ou p prop oses that a material’ s solu bility (i.e. carbon chai n length) d e termines the d e g ree of e c oto x icity. This is valid and co nsi s tent with the

curre n t theory on the mode of toxic action for non -p o l ar organi c m o lecule s (such as pet roleu m hydro c arbo ns) to aquati c org a n i sms (Peterso n, 1994; v an We zel an d O pperhui zen, 1 995). Thu s , the cate gory substa nces a r eJune 17, 2004 Page 11 of 44 Heavy Fuel Oils Consortium Registration # 1100997

considered as a single group. Furthermore, the st reams and products in the heavy fuel oil category are composed of constituent hydrocarbon co mpounds that also are represented in other petroleum product HPV categories that have substantial ecotoxicity data. Ther efore, the Testing Group has employed data from other categories as read across to describe potential ecotoxic ity for all streams and products in the heavy fuel oil category.

Because the compositions of the materials in this category va ry over time, it is not possible to specify in this Test Plan the exact chemical makeup of t he test samples that will be used in the mammalian testing. Specific analytical data on the test samples will be developed and made available when the samples are obtained. For a both the process subcategories and the re sidual fuel, the Testing Group will attempt to select test sample(s) that are thought to have the highest potential toxicities.

EVALUATION OF EXISTING HEALTH EFFECTS DATA AND PROPOSED TESTING

General Evaluation Reviews of this category of fuels have been published by two expert panels (CONCAWE , 1998; IARC, 1989). In preparing this Test Plan, the approach of the Testing Gr oup has been to review the available toxicology studies and include in the robust summary a detailed description(s) of the one study or a small number of studies that best address each SIDS Level 1 endpoint. Other studies are cited in the appropriate “Remarks” section of the Robust Summary and are intended to supplement the readers’ knowledge.

The Test Plan addresses the health effect s endpoints of the category by:

• Evaluating the toxicology database for the heavy fuel oil related refinery streams and products,

• Using read-across information whenever possibl e among category members, and other API HPV categories, and

• Proposing selected testing on representative samples.

H EALTH E FFECTS

Acute Toxicity The following acute toxicity results have been reported on representative samples of the seven heavy fuel oil subcategories:

Acute Oral Toxicity LD 50 value Species Observations

Residual Fuel Oils

(4 samples) 5.13 - >25 ml/kg bw Rat Lethargy; grease on fur

Process Subcategories

Atmospheric residue >5000 mg/kg bw Rat Stained coats; dark red areas in lung lobes Atmospheric distillate No studies available
- - Vacuum residue Data on two vacuum residuum samples (CAS no. 64741-56-6, API samples 81-13 and 81- 14) are presented in the API HPV Asphalt Test

Plan - -

Vacuum distillate (3 samples) >5000 mg/kg bw Rat ↓ Activity; chromorhinorrhea, ↓ fecal output; urogenital staining; ↓ urine

Cracked residue 4320 ♀ 5270 ♂ mg/kg bw Rat Mortalities; hypoactivity; piloerection; staining around mouth, nose,June 17, 2004 Page 12 of 44 Heavy Fuel Oils Consortium Registration # 1100997

urogenital; hair loss; weight loss; intestinal mucosa damage

Cracked distillate >5000 mg/kg bw Rat Oral, nasal discharge; lethargy; abnormal stools; pale & mottled kidneys

Reformer residue No studies available
- - UBTL, 1988,1990b; API, 1980a-d, 1982; Mobil, 1988b,c, 1992a

Acute Dermal Toxicity LD 50 value Species Observations

Residual Fuel Oils

(4 samples) >5 ml/kg bw Rabbit Erythema; slight congestion of liver Process Subcategories

Atmospheric residue >2000 mg/kg bw Rabbit Abnormal stool; dark red areas in lung Atmospheric distillate No studies available
- - Vacuum residue Data on two vacuum residuum samples (CAS no. 64741-56-6, API samples 81-13 and 81- 14) are presented in the API HPV Asphalt Test

Plan - -

Vacuum distillate (4 samples) >2000 mg/kg bw Rabbit ↓ Food consumption; soft
stool; ↓ fecal output

Cracked residue >2000 mg/kg bw Rabbit No signs systemic toxicity; no gross findings

Cracked distillate >2000 mg/kg bw Rabbit Erythema & edema; mottled kidneys

Reformer residue No studies available
- - API, 1980a-d, 1982; UBTL 1989a, 1992a,b

Dermal Irritation Irritation Index Species Observations

Residual Fuel Oils

(4 samples) 0.27 – 1.54 Rabbit Minimal – slight irritant

Process Subcategories

Atmospheric residue 3.5 Rabbit Moderately irritating Atmospheric distillate No studies available
- - Vacuum residue 0.18 Rabbit Not irritating

Vacuum distillate (4 samples) 1.2 – 3.6 Rabbit
-

Cracked residue 0.2 Rabbit
- Cracked distillate 5.6 Rabbit Moderately irritating

Reformer residue No studies available
- - UBTL, 1989d,e, 1992 d; API 1980a-d, 1982; Mobil, 1988a,b c, 1992a

Eye Irritation Irritation Indices Species Observations

24 & 72 hr

Residual Fuel Oils

(4 samples) 2.67 – 7.67 & 0 – 1.33 rinsed

4.0 – 7.33 & 0.0 – 1.33 un-rinsed Rabbit Minimal – mild irritant

Process SubcategoriesJune 17, 2004 Page 13 of 44 Heavy Fuel Oils Consortium Registration # 1100997

Atmospheric residue 0.0 & 0.0 un-rinsed only Rabbit Not irritating Atmospheric distillate No studies available
- - Vacuum residue 5.0 & 4.7 un-rinsed

5.7 & 4.7 rinsed Rabbit Un-rinsed - not irritating –

Rinsed - minimal irritant

Vacuum distillate (4 samples) 2.0 – 10.3 & 1.7* – 3.3* Rabbit Un-rinsed only

* 48 hr score

Cracked residue 2.0 & 0 rinsed & un-rinsed Rabbit Minimal irritant

Cracked distillate 5.7 & 0.0 un-rinsed

5.3 & 0.0 rinsed Rabbit Un-rinsed - not irritating Rinsed – not irritating

Reformer residue No studies available
- - UBTL, 1989f,g, 1991 API, 1980a-d, 1982; Mobil, 1988a,b, c, 1992a

Sensitization Challenge Response Species Observations

Residual Fuel Oils

(4 samples) - Guinea Pig 3 samples non-sensitizer 1 sample mild sensitizer Process Subcategories

Atmospheric residue 0/10 Guinea Pig Non-sensitizer Atmospheric distillate No studies available
- - Vacuum residue 0/10 Guinea Pig Non-sensitizer

Vacuum distillate 1/10 Gu inea Pig Non-sensitizer

Cracked residue 0/10 Guinea Pig Non-sensitizer

Cracked distillate 0/10 Guinea Pig Non-sensitizer

Reformer residue No studies available
- - API, 1980a-d, 1984; UBTL, 1986,1989b,c; 1990c, 1992c

Summary: No additional testing is planned. Multiple acute toxicity studies have been reported on a number of representative samples of the heavy f uel oil refinery streams as well as on finished residual fuels. These data

and data from the other 12 API HPV Test Plans show the acute toxicity of a wide-array of petroleum hydrocarbon streams is consistently low, with many oral LD50’s greater than 5 g/ kg, and dermal LD50s greater than 2 g/kg. While no data is presented for the vacuum residue process subcategory, the Testing Group thinks existing acute toxicity data on two vacuum residuum samples (CAS no. 64741-56-6, API samples 81-13 and 81- 14) presented in the API HPV Asphalt Test Plan support t he Group’s position that this subcategory of materials would have low acute toxicities. Similarly, although no data is presented for the atmospheric distillate or reformer residue subcategories, materials produced by these processes have been considered in other API HPV Test Plans that have consistently shown the acute toxicities of the materials to be low. Consequently, the Testing Group thinks the acute toxicities of these materials can be characterized by “Read Across” from

materials other API HPV Test Plans.

Repeat-Dose Toxicity Studies of up to 13 weeks duration have been reported for representative streams in a number of the process subcategories within the heavy fuel oil category. In in stances where there were multiple studies available for a subcategory, only the study of the longest duration wa s fully summarized in the attached Robust Summary (Appendix C).

Residual Fuel Oils Dose levels of 0.5 (496 mg), 1.0 (992 mg), or 2.5 (2480 mg) ml/kg bw /day of a heavy fuel oil (CAS no. 668476-33- 5) were applied undiluted to the skin of male and female rats (UBTL, 1987). The test material was applied 5x/week for 4 weeks. The test material produced minima l reversible dermal irritation at all dose levels. Daily observations of the animals found no compound-related effe cts other than staining at t he site of application. Similarly, there were no compound-related findings at nec ropsy other than the staining of the skin produced by

the test article.June 17, 2004 Page 14 of 44 Heavy Fuel Oils Consortium Registration # 1100997

Eosinophil counts were significantly lower for the mid-dose and high-dose males. SGPT levels were significantly lower for the low- and high-dose fema les and the high-dose males. Glucose levels were significantly higher for the mid- and high-dose female s and high-dose males. Total protein levels were significantly lower for the low-dose males. Hemoglobin le vels were significantly lower for the high-dose males. Upon comparison and review of historic data, the study directors concluded the significant values obtained from the hematology or clinical chemistry assays were with in normal limits and did not exhibit any clear dose-related

trends.

Relative liver weights were significantly higher for the females in all dose groups and in the high-dose males. With the exception of the liver/brain weight ratios in t he low-dose males, liver/body weight and liver/brain weight ratios were significantly higher for both sexes in all dose groups. The liver weight changes were thought by the study directors to be compound-related. Spleen/body weight ratios were significantly higher for the low and middose females and the high-dose males. The spleen/brain weight ratios were significantly higher for the lowdose females and the high-dose males. The changes in relative spleen weights were not thought to be doserelated by the study directors.

Microscopic examination of selected tissues from the control and high dose groups found no compound-related effects other than hyperk eratosis (minimal severity) at the test compound application site.

Process Subcategories

Atmospheric Residue Dose levels of 0.01 (9 mg), 0.25 (231 mg) or 1.0 (927.9 mg) ml/kg bw /day of an atmospheric residue (CAS no. 64741-45-3) were applied undiluted to the skin of male and female rats (UBTL, 1990a). The test material was applied 5x/week for 4 weeks. There were no clinical observations made that were considered to be treatment-related. The only treatment-related fi nding at gross necropsy was a dark staining of the treated skin site. There were no compound-related effects on either hematology or clinical chemistry values. Nor were there any treatment-related differenc es in body weights or organ weights or organ/body weight ratios. The only treatment-related histopathol ogical findings occurred in the skin and these consisted

of trace to mild acanthosis and trace to moderate hyperkeratosis in the high dose animals. The study authors concluded that there were no systemic effects at the highest dose level tested.

Atmospheric Distillates Dose levels of 30, 125 or 500 mg/kg bw /day of a heavy atmospheric gas oil (CAS no. 68783-08-4) were applied undiluted to the skin of male and female rats (M obil, 1992c). The test material was applied 5x/week for 13 weeks. To assess male reproductive health, a satellite group of 10 males was administered 500 mg/kg bw /day of the gas oil. At the end of the study the epididymides and te stes from the male rats in the control and 125 mg/kg bw /day groups were given an in-depth hi stopathology examination, including spermatid (testes) and spermatozoa (epididymides) count s. In general, application of the test material produced only “slight” skin irritation. On e of ten high dose males was sacrificed in extremis , the investigators considered the death to be treatment-rela ted. There were treatment-related changes in a number of serum chemistry and hematologi cal parameters in the rats in the mid- and high dose groups. At necropsy, treatment-related macroscopic findings in both sexes included increased liver size, decreased thymus size, thickening of the limiting ridge between the non-glandular and glandular sections of the stomach and enlarged and reddened lymph nodes. There were some organ weight (absolute and relative) differences in the 125 and 500 mg/kg bw /day groups. The histopathol ogy examination found treatmentrelated changes only in animals in the 500 mg/kg bw /day groups. These changes included a severe reduction in hematopoiesis in the bone marrow; liv er hypertrophy and connect ive tissue formation; increased areas of hematopoiesis, focal necrosis and i ndividual cell death in the liver; and a reduction in the numbers of lymphocytes in the thymus glands. T here were no treatment-related effects on any of the epididymal sperm or testicular spermatid parameters. The investigators concluded the no-observable-effect level (NOAEL) for the study was 30 mg/kg bw /day.

Vacuum Residue Data on repeat-dose toxicity studies in rabbits on two vacuum residuum samples (CAS no. 64741-56-6, API samples 81-13 and 81-14) are presented in the API HPV Asphalt Test Plan.June 17, 2004 Page 15 of 44 Heavy Fuel Oils Consortium Registration # 1100997

Vacuum Distillate An undiluted heavy vacuum gas oil (CAS no. 64741-57-7) wa s applied to the skin of male and female rats 5 days each week for 13 weeks (Mobil, 1988d). Dose levels were 30, 125, 500 & 2000 mg/kg bw /day. The unscheduled deaths of two of ten males in the high do se group were considered to be compound-related. Growth rates of males and females in the highest dose group were reduced compared to controls. At five and thirteen weeks, the 2000 mg/kg bw /day dose group had reduced erythroc ytes and platelets. Similar reductions were also found in the 500 mg/kg bw /day females. Changes in seve ral clinical ch emistry values were also seen in the 2000 mg/kg bw /day dose group. In addition in females dosed with 500 mg/kg bw /day had reduced serum glucose levels, while in the 500 mg/kg bw /day males, cholesterol was increased.

At gross necropsy, in the 500 and 2000 mg/kg bw /day dose groups, relative thymus weights were reduced while relative liver weights were increased. Histological examination revealed decreased erythropoiesis and fibrosis of the bone marrow in the 2000 mg/kg bw /day males. There was a reduction in thymic lymphocytes in both sexes in the 2000 mg/kg bw /day group. Examination of the testes of animals in the 2000 mg/kg bw /day dose group found no compound-related effect on sperm mo rphology. The investigators found the NOEL for both males and females was 125 mg/kg bw /day.

Cracked Residue Dose levels of 8, 30,125, 500 and 2000 mg/kg bw /day of a clarified slurry oil (CAS no. 64741-62-4) were applied undiluted to the skin of male and female rats (C ruzan et al., 1986; Mobil, 1985b). The test material was applied 5x/week for 13 weeks. There was an adverse , dose-related effect on mortality, with none of the rats in the highest dose group (2000 mg/kg/day) surv iving past the second week of the study. Compoundrelated effects were observed on body weights, and seve ral hematology and clinical chemistry parameters. Based on these changes, and histopathology findings, the target organs of toxicity were judged by the study directors to be the liver, thymus and bone marrow. T he investigators concluded that none of the dose levels used in the study represented a no-observabl e-adverse- effect le vel (NOAEL).

Cracked Distillate
Dose levels of 8, 30 and 125 mg/kg bw /day of a visbreaker gas oil 

### ( CAS no. 68471-81-7) were applied undiluted to the skin of male and female Sprague-Dawley rats (Feuston et al., 1994; Mobil, 1992b). The test material was applied 5x/week for 13 weeks. There were no deaths during the study. No clinical signs of toxicity were observed, with the exception of dose-related skin irritati on. There were no compound-related effects on body weights or hematology and clinical chemistry values. Urinalysis found no treatment-related effects. At necropsy, the only treatment-related fi ndings were effects on the skin and enlarged lymph nodes (the latter predominantly in the higher dose groups) . Microscopic examination of the skin revealed thickened epidermis with parakeratosis, chronic inflamma tion in the subcutis, ulcers and increased mitosis in the epidermal basal cells. The skin changes were more severe in females than the males. Lymph nodes were enlarged in the high dose animals and in most instances, microscopic examination revealed nonspecific reactive hyperplasia. Epididymides and testes from the male rats in the control and 125 mg/kg bw /day groups were given an in-depth histopathology examination, including spermatid (testes) and spermatozoa (epididymides) counts. Treatment with visbreaker gas oil did not cause any changes in testicular spermatid or epididymal spermatozoa count nor in sperm morphology. The investigators concluded the NOAEL in the study was > 125 mg/kg bw

.

Reformer Residue

No studies available.

Carcinogenicity In addition to the repeat-dose studies discussed above, several dermal carcinogenicity studies on samples of cracked residual streams have been reported (API, 1989; McKee et al., 1990; Smith et al., 1951). Although carcinogenicity is not a required endpoint of the HPV program, the Testing Group believes the results may be useful in evaluating the repeated-dose endpoint. A tabulat ion of these studies can be f ound in section 5.7 of the attached Robust Summary (Appendix C).

Summary: The Testing Group proposes to test a representative sample of a reformer residue stream by the dermal route of administration using a 28-day repeated-dose/reproductive/developmental toxicityJune 17, 2004 Page 16 of 44 Heavy Fuel Oils Consortium Registration # 1100997

screening protocol (OECD Test Guideline 422). No repeat dose information exists on the reformer residue

streams. While no data is available for the vacuum residue process subcategory, the Testing Group thinks these materials can be characterized by “read across” fr om the data on the vacuum residue streams found in the API HPV Asphalt Test Plan.

In-Vitro (Mutagenicity)

Subcategory Assay Results

Residual Fuel Oils No studies to report
- Process Subcategories

Atmospheric residue No studies to report
- Atmospheric distillate No studies to report
- Vacuum residue Mouse lymphoma - data on two vacuum residuum samples (CAS no. 64741-56-6, API samples 81-13 and 81-14) are presented in the API HPV Asphalt Test Plan Weakly positive with activation

Vacuum distillate Modified Ames– Positive with activation Cytogenetic assay with Chinese

Hamster Ovary cells Negative with/without activation

Cracked residue Modified Ames Positive with/without activation Mouse lymphoma Positive with/without activation Sister chromatid exchange Positive with/without activation

Cell transformation Negative without activation

Positive with activation

Unscheduled DNA synthesis Positive

Bacterial forward mutation Negative with/without activation

Cracked distillate No studies to report
- Reformer residue No studies to report
- API, 1985a,b, e, f, 1986b,c; Mobil, 1985a, 1987e

Summary: The Testing Group is proposing to perform a modified Ames and chromosomal aberration (OECD 473) assays on representative samples of a residual fuel oil, atmospheric residue, atmospheric distillate, cracked distillate and reformer residue.

In-Vivo (Chromosomal Aberrations)

Subcategory Assay Species Results

Residual Fuel Oils No studies to report
- - Process Subcategories

Atmospheric residue No studies to report
- - Atmospheric distillate No studies to report
- - Vacuum residue Cytogenetic Assay - data

on two vacuum residuum samples (CAS no. 64741- 56-6, API samples 81-13 and 81-14) are presented in the API HPV Asphalt Test

Plan Rat ( ♀

, ♂ ) Negative at up to 3 g/kg/day by gavage for 5 days

Vacuum distillate Micronucleus Rat ( ♀

, ♂ ) Negative at up to 2000 mg/kg bw /day; 5x/week for 13 weeks

via dermal route

Cracked residue Cytogenetic Assay Rat ( ♀

, ♂ ) Ne g ative at u p to 1 g /k g /da y b yJune 17, 2004 Page 17 of 44 Heavy Fuel Oils Consortium Registration # 1100997

gavage for 5 days Sister Chromatid Exchange Mice ( ♀

, ♂ ) Single IP dose - positive at 4.0 ( ♀

, ♂ ) & 2.0 ( ♂ ) g/kg bw ; negative at 0.4 g/kg bw Unscheduled DNA Synthesis Rat ( ♂ ) Positive at 100 & 1000 mg/kg bw by gavage; negative at 50 mg/kg bw Cracked distillate No studies to report
- - Reformer residue No studies to report
- - API, 1985c,d, e; Mobil, 1987f

Summary. No additional in-vivo testing is planned. Adequate studies exist on the vacuum distillate and cracked residue subcategories. The Testing Group thinks results from the API HPV Gas Oils test plan can be “read across” to the atmospheric distillate subcategory given the similar process history. Similarly, the Testing Group thinks results on vacuum residue streams from the API HPV Asphalt test plan can be “read across” to characterize the vacuum residue subcategory. Given the high aromatic content of the cracked distillates and reformer residues, the Testing Group would expect these types of material s would produce positive results in the Ames assays. Other materials with high PAC content (aromati c extracts) have produced negative results in

in vivo chromosomal aberration assays. If the in vitro assays are positive, the Testing Group will consider

additional in vivo testing.

Reproductive/Developmental Toxicity

Residual Fuel Oils No studies to report.

Process Subcategories

Atmospheric Residue In a developmental screening study, dose levels of 50, 333, & 1000 mg/kg bw /day of an atmospheric residue (CAS no. 64741-45-3) were applied to the skin of presum ed-pregnant female rats on days 0-20 of gestation (UBTL, 1994). There were no deaths or treatment-rela ted clinical effects amongst the dams. The study directors considered decreased body weight changes and the increase in gestat ion length at a dose of 1,000 mg/kg to be signs of compound-related maternal to xicity. Signs of developmental toxicity considered by the study directors to be co mpound-related included decreased pup body weights on Lactation Days 0 and 4 at a dose of 1,000 mg/kg. The report authors concluded that for maternal toxicity and signs of developmental toxicity the no-observable-adv erse-effect level (NOAEL) was 333.0 mg/kg bw /day.

Atmospheric Distillate A developmental toxicity screening study has been reported on a heavy atmospheric gas oil (CAS no. 68783-08-4) (Mobil, 1991). Undiluted test material was applied daily on days 0 to 19 of gestation to the clipped skin of resumed-pregnant female rats. Dose levels included 8, 30, 125 and 500 mg/kg bw /day. Signs of maternal toxicity considered by the study director to be related to administration of the test material included effects on body weights, body weight gain, f ood consumption, thymus weights (absolute & relative), liver weights (relative), and a number of c linical chemistry and hematological parameters

. A red vaginal discharge (normally indicative of litter resorption) was observed in 7/11 animals in the 500 mg/kg bw /day group and two females dosed with 125 mg/kg bw /day. The investigators could not decide if the vaginal discharge was treatment-related since a similar observation had been noted in control animals. Evaluation of reproductive parameters in the 8 and 30 mg/kg bw found no compound-related e ffects. Statistically insignificant differences in preimplantation losses were seen in both the 125 and 500 mg/kg bw /day groups. There was a significant increase in the mean number/percent resorptions in the 500 mg/kg bw /day group. Mean fetal body weights were significantly decreased for all viable fetuses in the 500 mg/kg bw /day group and in the male pups of the 125 mg/kg group. There was a significant increase in incomplete ossification of a number of skeletal structures (nas al bones, thoracic centra, caudal centra, sternebrae, metatarsal and pubis) in the 125 and 500 mg/kg bw /day groups. There were no treatment-related abnormalities found in the soft tissues. Exposure to gas oil did not adversely af fect pup survival or development. The investigatorsJune 17, 2004 Page 18 of 44 Heavy Fuel Oils Consortium Registration # 1100997

concluded the no-observable-adverse -effect levels (NOAELs) for both maternal toxicity and teratogenicity were 30 mg/kg bw /day.

Vacuum Residue No studies to report.

Vacuum Distillate In a developmental screening study, dose levels of 30, 125, 500 and 1000 mg/kg bw /day of a heavy vacuum gas oil (HVGO, CAS no. 64741-57-7) were applied to the skin of presumed-pregnant female rats (Mobil, Undated). The test material was administered on days 0 to 19 of gestation. All animals were euthanized on day 20. Clinical signs of maternal toxicity cons idered by the study authors to be compound-related were seen primarily in the 1000 mg/kg bw /day dose group. In the dams, the only treatment-related findings seen at necropsy were lungs that had a pale appearance (500 and 1000 mg/kg bw /day) and a reduction in thymus size. Organ weight data confirmed that the thymus we ights in the highest dose group were reduced and furthermore, relative liver weights were in creased in the 500 and 1000 mg/kg/day animals. A number of reproductive parameters were affected by treatment wi th HVGO. Fetuses of dams in both the 500 and 1000 mg/kg bw /day dose groups had treatment-related decreases in body weights. Upon external examination, one fetus in the 1000 mg/kg bw /day group was found to be edematous, pale in color, with both hind paws

malformed. Malformations of the vertebral columns were observed in several fetuses, but only in the 500 mg/kg bw /day group. While a variety of skeletal malf ormations were observed in both treated and control groups, the degree of malformation was more severe in the HVGO-exposed groups. Visceral malformations were restricted to two fetuses in the 500 mg/kg bw /day group. Of the two fetuses, one had microphthalmia and the other had a diaphragmatic hernia that displaced the heart from the left- to right-hand side. The study authors concluded the no-observable-adverse-effect levels (NOAELs) for both maternal and fetal toxicity were 125 mg/kg bw /day.

Cracked Residue A developmental toxicity screening study has been repor ted on a clarified slurry oil (CSO, CAS no. 64741- 62-4) (Hoberman et al., 1995). Undiluted test material was applied daily on days 0 to 19 of gestation to the clipped skin of resumed-pregnant female rats. Do se levels included 0.05, 1.0, 10, 50 or 250 mg/kg bw /day. No deaths occurred among the dams and no dam abo rted or prematurely delivered a litter. Neither maternal toxicity nor fetal developmental effects were seen at the 0.05 mg/kg bw /day dose level. Nor were any fetal malformations or variations observed in the 0.05 mg/kg bw /day group. Dose-related signs of maternal toxicity were seen at dose levels greater than 0.05 mg/kg bw /day. The effects included decreased food consumption and decreased body and gravid uterine weights, and the occurrence of red vaginal exudates. Fetal developmental effects, as measured by number of live fetuses, total resorptions, early resorptions, % dead or resorbed conceptuses/litter and fetal body weights were seen at doses that were maternally toxic. There were no treatment-related inci dences of fetal malformations. However, increased incidences of fetal variations that are generally in terpreted as reversible delays in development associated with significant decreases in body weight were produced in fetuses in the 1.0, 10 and 50 mg/kg bw /day dose groups. These variations included moderate dilation of the renal pelvis, slight dilation of the lateral ventricles of the brain, bifid thoracic vertebral c entrum and decreased average numbers of ossified caudal vertebrae, metacarpals and hindpaw phalanges. T he study authors concluded the no-observable-adverseeffect levels (NOAELs) for both maternal and fetal toxicity were 0.05 mg/kg bw /day.

To determine potential effects on gonadal function, re productive organs and mating behavior, 0.1, 1, 10, 50 & 250 mg/kg/day of a clarified slurry oil (CAS no. 64741-62-4) were applied dermally to male rats for 70 days before a seven-day cohabitation pe riod with untreated virgin female rats (Argus, 1992). Female rats were examined daily for viability and clinical observations, and body weights were recorded on days 0, 6 and 14 of presumed gestation. On day 14 of presumed ge station, the female rats were sacrificed by carbon dioxide asphyxiation, and a gross necropsy of the thoracic and abdominal viscera was performed. The uterus of each rat was examined for pregnancy, number and distribution of implantations, early resorptions and live and dead embryos. No deaths and no skin reactions were caused by the test material. All absolute and relative organ weights were comparable among the six dosage groups. There were compound-related effects on body weights, body weight gains, and food consumption. Mating and fertility parameters were unaffected at any of the dose levels. There were no co mpound-related effects on any testicular parameter.June 17, 2004 Page 19 of 44 Heavy Fuel Oils Consortium Registration # 1100997

Litter averages for corpora lutea, implantations, and liv e embryos and resorptions did not significantly differ among females mated with male animals from the six dosage groups. There were no dead embryos, and no dam resorbed all conceptuses. The study director s concluded that the pater nal no-observable-adverseeffect-level (NOAEL) was 1 mg/kg/day. The reproducti ve NOAEL for the male rats was >250 mg/kg/day (no mating, fertility or testicular parameters in the male rats were affected by t he highest dosa ge tested).

In a reproductive/developmental toxi city screen, female Sprague-Dawley rats were administered catalytically cracked clarified oil (CAS no. 64741-62-4) at dose levels of 0.05, 10, 250 mg/kg/day (UBTL, 1994). The test material was administered one week prior to the init iation of mating, throughout mating, and through Day 20 of gestation. Male rats to which the females were mated were not administered test compound. Food consumption and body weights were recorded throughout the premating, mating and gestation periods. On Day 4 of lactation, each female was sacrificed and th e ovaries and uterine horns examined to determine the number of corpora lutea and implantation sites, resp ectively. Litters were observed during Days 0 –4 of lactation for signs of toxicity and mortality. Pups we re examined daily for external abnormalities. On Days 0 and 4 of lactation, each pup was weighed and its sex was determined. On day 4 of lactation, all surviving pups were examined externally, sacr ificed and discarded. No deaths oc curred during the study. The study directors considered the following signs of maternal to xicity to be related to administration of the test material: a higher incidence of vaginal discharge at a dose of 250 mg/kg; decreased body weights, body weight changes, and food consumption at doses of 10 and 250 mg/kg; and decreased thymus size at a dose of 250 mg/kg. Signs of developmental toxicity co nsidered to be compound-related were limited to the 250 mg/kg dose group; none of the females in this dose level delivered a litter. The study directors concluded the no-observable-adverse-effect levels (N OAEL) were 0.05 mg/kg for maternal toxicity and 10 mg/kg for signs of developmental toxicity.

Cracked Distillate Doses of 8, 30, 125 and 250 mg/kg bw /day of a heavy coker gas oil (CAS no. 64741-81-7) were applied daily to the skin of resumed-pregnant female rats in a dev elopmental screening study (Mobil, 1987d). Animals were dosed on days 0-19 of gestation. All animals were euthanized on day 20. Treatment-related clinical

observations in the dams consisted of erythema, flaking, scabbing, edema, eschar and fissuring and the occurrence of a red vaginal discharge. Eschar and fiss uring occurred in the highest two dose groups only. Vaginal bleeding was seen in the groups receiving doses of 30 mg/kg bw/day and higher. There was a doserelated decrease in mean body weight gains over th e course of the experiment. At necropsy, the only treatment-related observation in the dams was an apparent reduction in thymus size, which was noted at all treatment levels. Absolute thymus weights were decreased, while absolute liver weights were increased. A number of clinical chemistry values were affe cted, but only at the highest dose of 250 mg/kg bw /day. Select reproductive parameters were adversely affected, but only in the 125 and 250 mg/kg bw /day groups. Viable

and non-viable fetuses from these two dose levels were observed to have signs of abnormal external development, including reduced (shortened) lower jaws and edema. Visceral anomalies seen in these same two dose groups included displacement of esophag us from a left-sided to a right-sided position and

distension of the ureters. Malformations of the verteb ral column were restricted to fetuses of dams exposed to the test material. Although signs of aberrant dev elopment were observed in control animals, the degree

of the observed effects was not as severe in the control groups as the groups exposed to test material. The

authors concluded that the no-observable-adverse-effe ct-level for maternal and fetal toxicity was 30 mg/kg bw /day.

Reformer Residue No studies to report

Summary: The Testing Group proposes to test a representative sample of a residual fuel oil by the dermal route of administration using a reproduct ive/developmental toxicity screening protocol (OECD Testing Guideline 421). The Testing Group proposes to test a representative sample of a reformer residue by the dermal route of administration using a 28-day repeatdose/reproductive/developmental toxicity screening protocol (OECD Test Guideline 422). The Testing Group thinks the existing data on refinery streams in the process subcategories allows the developmental toxicity of these materials to be characte rized. While no data exists for the vacuum residue subcategory, the Testing Group believes the physical nat ure of these materials (very viscous) will limit theJune 17, 2004 Page 20 of 44 Heavy Fuel Oils Consortium Registration # 1100997

bioavailability of any potentially biol ogically significant components. Furthermore, data is available for atmospheric residuum, a similar material, which because of its lower boiling point will contain higher levels of these potentially biologically significant components. Therefore, the Testing Group is not proposing any testing for this subcategory of materials. No reproduct ive or developmental data is available for the reformer residue streams. However, the Testing Group has al ready proposed a repeat-dose study on a reformer residue. The Testing Group is proposing to maximi ze the utility of the study by conducting a 28-day repeated-dose/reproductive /developmental toxicity screen (OECD Test Guideline 422). This will provide data not only on the repeat-dose toxicity of this subc ategory of materials, but al so on their reproductive/ developmental toxicity thereby adding to the extens ive database that exists on these materials.

While none of the developmental studies summarized in this test plan provide data on pre-mating exposure of males or females, the existing data adequately characte rize the reproductive endpoint for these materials. Repeat-dose studies on samples of atmospheric distilla tes, vacuum distillates, and cracked distillates have included an in-depth histopathological examination of reproductive organs. Furthermore, studies have been reported on catalytically cracked clarified oil (cracked residue) in which pre-mating exposures of males or females were conducted. Catalytica lly cracked clarified oil has produced the lowest maternal no-observedadverse-effect-level (NOAEL) in t he developmental screens that have been performed. The Testing Group expects the reproductive toxicity of the other materials in this category to be less than that of catalytically

cracked clarified oil.

The lack of reproductive/developmental toxicity data on a finished residual fuel suggests the need for a reproductive/developmental screen on a representative sample of a residual fuel. The Testing Group is proposing a reproductive/developmental toxicity screen (OECD Test Guideline 421) of a residual fuel in order to develop a complete data set on a finished product and to test its hypothesis that the toxicity of the finished fuel will fall within the range of the toxicities of the streams from which the fuel is blended. To that end, the Testing Group will select a residual fuel test sample that is well characterized with respect to the components from which it was blended. The goal will also be to select a residual fuel oil sample that has a significant portion of cracked residu es since these streams appear to sh ow the highest potential for toxicity within this category.

EVALUATION OF EXISTING PHYSICO -CHEMICAL AND ENVIRONMENTAL FATE DATA AND PROPOSED

TESTING

The physicochemical endpoints for the EPA HPV chemical program include melting point, boiling point, vapor pressure, octanol/water partition coefficient (log K

ow ), and water solubility. Environmental fate endpoints include photodegradation, hydrolysis, environm ental transport and distribution (fuga city), and biodegradation. Although some data for products in this category exist, not a ll of these endpoints are defined and a consensus database for chemicals that represent products in this category does not exist. Therefore, calculated and measured data

have been identified and a technical discussion provided, where appropriate. The EPIWIN © (EPA, 2001) computer model, as discussed in the U.S. EPA document entitled "The Use of Structure-Activity Relationships(SAR) in the High Production Volume Chemicals Challenge Program" has been used to calculate physicalchemical properties of representative cons tituents of heavy fuel oils (EPA, 1999).

The substances covered under this HPV testing plan ar e mixtures of differing compositions. Because of the diversity of compounds encompassing heavy fuel oils, it is not feasible to model the physicochemical endpoints for each potential compound. Where modeling was necessary to fulfill an endpoint, such estimates were made for common hydrocarbon structures (e.g., saturated, aromatic, olefinic and heterocyclic hydrocarbons) and range of molecular weight hydrocarbons (i.e., number of carbon atoms) known to be represented in heavy fuel oil mixtures. Since molecular weight and structural conf ormation determine in large part many of the physicochemical and fate processes, the modeled estimates for these isomeric structures are expected to represent potential ranges of values for all substances in the heavy fuel oil category.June 17, 2004 Page 21 of 44 Heavy Fuel Oils Consortium Registration # 1100997

Physico-Chemical Data

Melting Point For complex mixtures like petroleum products, melting point may be characterized by a range of temperatures reflecting the melting points of the individual component s. To better describe the physical phase or flow characteristics of petroleum products, the pour point is r outinely used. The pour point is the lowest temperature at which movement of the test specimen is observed under prescribed conditions of the test (ASTM, 1999).

Measured pour points ranged from –2 ° C to 35 ° C (CONSCI, 1992a,b; CONSCI, 1993a-d; Jokuty et al., 2002; NIPER, 1993a,b). Those values are consistent with t he review by CONCAWE (1998), which stated pour points for these products are typically <30 ° C. The differences in flow characteristics of heavy fuels are related to the composition of the crude oil from which they are produced, the variety of refining practices that result in products that go into heavy fuels, and the practice of adding a lighter “cutter stock” to heavy fuel oils to improve their flowable characteristics at low temper atures. Based on the cited data, hea vy fuel oil streams and products will exist at ambient temperatures as de nse, viscous oil. Those category me mbers with the highest pour points will be characteristically solid to semi-solid substances, while those with the lowest pour points will have the greatest liquefaction.

Summary: No additional testing is proposed. The pour points of various heavy fuel oils have been adequately measured.



### Boiling Point
For complex petroleum mixtures, boiling points are expr essed as ranges (i.e., distillation ranges) that are governed by the individual constituent hydrocarbons within the mixtures. Constituent molecules have individual boiling points, and boiling points increase as molecular we ight increases. Streams within the Heavy Fuel Oil HPV category are highly diverse mixtures, and are produce d from a variety of refining processes; processes including both atmospheric and vacuum distillation; therefore, the boiling ranges of the streams also would be expected to vary widely. Based on CAS definitions for t he refining streams in this category, boiling points can range from 121 to 600 ° C (EPA, 2004). Actual boiling ranges for any of the heavy fuel oil streams will depend upon source of the feedstock and the refining process. Boiling ranges reported in various literature sources such as material safety data sheets (Sinclair O il Corp; Total UK Ltd., 2003; and TFMM, 2001), governmentsponsored databases (ECB, 2000; Jokuty et al., 2002) , and the American Petroleum Institute (API, 1987) lend support to the CAS-defined boiling range.

Summary: No additional testing is proposed. Products within this category vary with respect to their distillation ranges and specific ranges depend upon the hydrocarbon composition of the feedstocks from which they are produced. Values cited provide typical ranges for the distillation of these materials.

Vapor Pressure Few vapor pressure measurements ar e available for heavy fuel oils; therefore, the EPIWIN (EPA, 2001) computer model was used to estimate vapor pressures fo r representative components of these substances. For heavy fuel oil mixtures, the total vapor pressure is the sum of the partial pressures of the individual components (Dalton’s Law of Partial Pressures), while the partial pr essure of an individual constituent is a product of the vapor pressure of the pure material times its mole fracti on in the mixture (Raoult’s Law). Therefore, for complex mixtures such as heavy fuel oils, the partial pres sures of individual constituents may be quite low.

The heavy fuel oil category is composed of many differ ent refining streams, and the vapor pressures of such substances will vary with the source of the crude and the refining method used. Measured values of <100 Pa (Total UK Ltd, 2003) and >500 Pa (ECB, 2000) for two heavy fuel oil streams reflected this variability. Vapor pressure estimates made using EPIWIN © version 3.10 (EPA, 2001) for cons tituent hydrocarb ons representing paraffinic, olefinic, naphthenic, aromatic, and polar/heter ocyclic components in heavy fuel streams bounded the measured data. Vapor pressure estimates of low mo lecular weight hydrocarbons (C7 – C11) of varying isomeric structures ranged from 7 Pa to 9 x 10 3 Pa. As molecular weights increased, vapor pressure estimates decreased. Estimates for the high molecular weight constituents (C38 – C50) ranged from 2 x 10 -7 Pa to 5 x 10 -

17 Pa. The modeled data represent a potential vapor pr essure range for the hydr ocarbon constituents expected to occur in all subcategories of heavy fuel oils.June 17, 2004 Page 22 of 44 Heavy Fuel Oils Consortium Registration # 1100997

Summary: No additional testing is proposed. The vapor pressures of representative hydrocarbon constituents of heavy fuel oils have been adequately characterized. Measured data reflect the variability expected for substances in this category.

Partition Coefficient In mixtures such as the heavy fuel oils, the percent distribution of the hydrocarbon groups (i.e., paraffins, naphthenes, olefins, aromatics, pol ar/heterocyclics) and the carbon chain lengths determines in-part the partitioning characteristics of the mixture. Generally, hydrocarbons with fewer carbon atoms tend to have lower partition coefficients than those with higher carbon numbers (CONCAWE, 2001). However, due to their complex composition, unequivocal determination of the log K

ow of the hydrocarbon mixtures cannot be made. Rather, partition coefficients of representative hydrocar bon types covering the range of carbon atoms found in substances in this category were modeled using the EPIWIN © , version 3.10 computer model (U.S. EPA, 2001).

The isomeric structures and numbers of carbon atoms we re selected because they are representative of the types and molecular weights of hydrocarbon compounds f ound in heavy fuel oils. Therefore, the estimated values represent the potential range of values for part ition coefficient for hydrocarbon constituents in this category. The estimates show log K

ow values to range from 1.7 to 25. Standardized methods for measuring partition coefficient are analytically limited to substance up to log Kow ~4, or occasionally 5 (OECD, 1995). An estimation method is available for log Kow up to 6 (OE CD, 1989). Based on the estimated values determined by EPIWIN © , available analytical methods begin to fail for hy drocarbon compounds that contain roughly 15 to 20 carbon atoms. The modeled data represent a potent ial log Kow range for the hydrocarbon constituents expected to occur in all subcategories of heavy fuel oils.

Summary: No additional modeling is proposed. Partition coefficients (K

ow ) of 1.7 to 25 were calculated for representative hydrocarbon components of heavy fuel oils.



### Water Solubility

When released to water, dissolution of the water-so luble constituents in heavy fuel oils will depend upon environmental factors affecting t he mixing and weathering of the substance. Lower molecular weight components that have the highest solubilities also have appreciable vapor pressures and thus would tend to

both dissolve and volatilize from the surface. Under controlled conditions with minimal opportunity for volatilization, the water solubility of heavy fuel oil no. 6 was measured to be 6.26 mg/l (Shiu et al., 1990). Additional supporting data gave a range of water solubilitie s from 0.4 to 6.3 mg/l (Suntio et al., 1986; Anderson et al., 1974; MacLean and Doe, 1989). Because blended f uels are composed of the refining streams from which they are produced, these solubility values are expected to approximate the water solubility for all substances within the heavy fuel oil subcategories. Specific solu bility values for heavy fuels oils and the refining streams are dependent upon the composition of the crude oil and t he refining process that it undergoes. Calculated and measured water solubilities differ for individual component s of complex petroleum substances. At any particular loading rate, aqueous concentrations of each component are a function of relative volume of aqueous and petroleum phases, partition coefficient between phases, amount of component present and the maximum water solubility of each component. Summary: No testing modeling is proposed. Reported water solubility values for heavy fuel oils ranged from 0.4 to 6.3 mg/l.

Environmental Fate Data

Photodegradation The direct aqueous photolysis of an organic molecule occurs when it absorbs sufficient light energy to result in a structural transformation. Only light energy at wavelengths between 290 and 750 nm can result in photochemical transformations in the environment, although ab sorption is not always sufficient for a chemical to undergo photochemical degradation. Saturated and one-ri ng aromatic hydrocarbons do not show absorbance in the 290 to 800 nm range and would not be expect ed to be directly photo-deg raded. Polyaromatic hydrocarbons (PAHs), on the other hand, have shown abs orbance of the 290 to 800 nm range of light energy and are capable of being degraded by ultraviolet radi ation (Fasnacht and Blough, 2002). The degree and rate at which these compounds photo-degr ade depends upon whether conditions allow penetration of light withJune 17, 2004 Page 23 of 44 Heavy Fuel Oils Consortium Registration # 1100997

sufficient energy to effect a change. In laboratory experi ments, ultraviolet illumination of thin films of heavy fuel oil led to disappearance of polyaromatic compounds (Garrett et al., 1998). The loss was more pronounced for larger polycyclic species and the more alkylated forms of the parent hydrocarbon. This pattern of loss also was

demonstrated in situ , where disappearance of PAHs on painted granite panels placed in an intertidal marine location was greatest for larger and more alkylated species (Jezequel, et al. 2003).

Hydrocarbon components in heavy fuel oils are subject to indirect photodegradation within the tropospheric layer of the atmosphere. Indirect photodegradation is the reaction with photosensitized oxygen in the atmosphere in the form of hydroxyl radicals (O H) and other oxygen containing radicals (e.g., NO 3 ). The potential to undergo indirect photodegra dation estimated using the atmosphe ric oxidation potential (AOP) model subroutine (AOPWIN V1.90) in EPIWIN © (EPA, 2001), which calculates a c hemical half-life and an overall OH reaction rate constant based on a 12-hour day and a given OH concentration. Atmospheric oxidation half-lives were calculated for the various molecular weight and isomeric structures representing constituent hydrocarbons (paraffins, naphthenes, olefins, aromatics, and polar/heteroc yclics) in heavy fuel oils. Structures and molecular weights of selected constituents we re chosen on the basis of carbon number as identified in the category substances and known hydrocarbon composition of heavy fuel oils. Therefore, the estimated values identify a potential AOP range for substances in the heavy fuel oil ca tegory. AOP half-lives for heavy fuel oil hydrocarbon constituents ranged from <0.1 day to 5.2 days. The modeled data represent a potential range of photodegradation half-lives for the hydr ocarbon constituents expected to occur in all substances in the heavy fuel oil category.

Summary: No additional modeling is proposed. Atmospheric half-lives of <0.1 to 5.2 days have been calculated for representative hydroc arbon components of heavy fuel oils.

Stability in Water Chemicals that have a potential to hydr olyze include alkyl halides, amides, carbamates, carboxylic acid esters and lactones, epoxides, phosphate esters, and sulfonic acid esters (Harris, 1982). Because heavy fuel oils do not contain significant levels of these functional groups, materials in the heavy fuel oils category are not subject to hydrolysis.

Summary: Computer modeling will not be conducted for materials in the heavy fuel oils category because they do not undergo hydrolysis.

Chemical Transport and Distribution in the Environment (Fugacity Modeling) Fugacity-based multimedia modeling provides basic info rmation on the relative distribution of chemicals between selected environmental compartments (e.g., air, wa ter, soil, sediment, suspended sediment and biota). The US EPA has agreed that computer-modeling techniques are an appr opriate approach to estimating chemical partitioning (fugacity is a calculated, not m easured endpoint). A widely used fugacity model is the EQC (Equilibrium Criterion) model (Trent University, 1999). The EQC model is a Level 1 (i.e., steady state, equilibrium, closed system and no degradation) model that utilizes the input of basic chemical properties including molecular weight, vapor pressure, and water solubility to calculate distribution within a standardized regional environment. EPA cites the use of this model in its document “Determining the Adequacy of Existing Data” that was prepared as guidance for t he HPV chemicals program (U.S. EPA, 1999).

Based on the physical-chemical characteristics of co mponent hydrocarbons in heavy fuel oils, the lower molecular weight components are expected to have the hi ghest vapor pressures and water solubilities, and the lowest partition coefficients. These factors enhance th e potential for distribution in the environment. To gain an understanding of the potential transport and distribution of heavy fuel oil components, the EQC model was used to characterize the environmental distribution of hydr ocarbons having different molecular weight and isomeric structures. Structures and molecular weights of se lected constituents were chosen on the basis of carbon number as identified in the category substances and kn own and estimated hydrocarbon composition of heavy fuel oils (Potter and Simmons, 1998; Quann and Jaffe, 1992; Saeger and Jaffe, 2002). Therefore, the estimated values identify the potential environmental distribution for component hydrocarbons in the Heavy Fuel Oil Category.June 17, 2004 Page 24 of 44 Heavy Fuel Oils Consortium Registration # 1100997

Partitioning behavior of constituent hy drocarbons of substances in the H eavy Fuel Oil Category depends largely on molecular weight, with smaller compounds (e.g., 7 to 12 carbon atoms) partitioning to the air or water according to their vapor pressure or water solubility prope rties. In the atmosphere they are expected to degrade rapidly via indirect photodegradation processes, while water soluble components are subject to biodegradation. Once hydrocarbons attain a size of approximately 20 carbon atoms, their low vapor pressure and water solubility prevent their partitioning to air or dissolving in water. Much real-world information has been gained from studies on heavy fuel oil spills (Fuel oil #6 or Bunker C) since this oil is carried by all carg o ships and is the most frequently spilled oil (Jezequel et al. 2003). When spilled on water, heavy fuel oil usually spreads into
thick, dark colored slicks that will often breakup into discrete patches and tar balls (NOAA, 2004). Only the lowest molecular weight fractions would be expected to disperse into the water column, and only 5-10% of the material is expected to evaporate within the first few hours of a spill. The specific gravity of a particular fuel oil may vary from 0.95 to 1.03; thus, spilled oil can float, su spend, or sink (NOAA, 2004). Small changes in water density may dictate whether the oil will sink or float. With time and the effects of weathering, heavy fuel oil attains a tar-like consistency, and t hese fractions will become incorporated into soil or bottom sediments where they will undergo slow to moderate biodegradation. Overa ll, the principle routes of weathering of spilled heavy fuel include physical removal, dissolution, photo- oxidation, and biodegradation (Jezequel, et al. 2003).

Summary: No further modeling is proposed . Fugacity-based computer modeling has been done for representative constituent hydrocarbon components of heavy fuel oils.

Biodegradation Extensive research on oil degradation in marine environments indicates that virtually all kinds of oil are susceptible to microbial oxidation. When a heavy fuel oil is spilled, shoreline microbial communities respond quickly to the oiling, with numbers of hydrocarbon-degrading microbes and mineralization potentials increasing after exposure (Leahy and Colwell, 1990). The rate of mi neralization is influenced by microbial characteristics (e.g., species), and environmental factors such as available nutrients, oxygen, temperature and degree of dispersion (Mulkins-Phillips and Stewart, 1974; Rashid, 1974; Prince, 2002; Garrett, et al., 2003). In marine systems, degradation is most enhance d by the addition of nutrients (nitr ogen and phosphorus), as these are considered most limiting in seawater (Richmond et al., 2001). In general, due to the high viscosity of heavy fuels, their tendency to slowly weather into discrete ta r balls, and the eventual incorporation of those substances into soil/sediment can physically isolate and prevent dispersion and microbial attack (Richmond et al., 2001; Prince et al., 2003). However, over time, com ponent hydrocarbons are depleted through selective biodegradation (Lee, et al. 2003). This structure-rela ted trend shows hydrocarbons in order of increasing difficulty for biodegradation to be: 1) n-alkanes, 2) isoa lkanes, 3) alkenes, 4) monoaromatic alkylbenzenes, 5) polyaromatic compounds, and 6) high molecular weight cycloalkanes (Bartha and Atlas, 1977; Potter and Simmons, 1998). Less is known about the biodegradability of polar components in oils, which are collectively known as asphaltenes and resins. Many of these have molecular weights of 2000 to 5000 and show little degradation; hence they can per sistent in the environment for a long ti me (Prince, 2002; Prince et al., 2003). In standard 28-day studies, heavy fuel oils would not be expected to be readily biodegradable. In one study, Walker et al. (1975) measured an 11% biodegradation of Bunker C fuel oil over 28 days when incubated with a mixed culture of estuarine bacteria in a nutrient medium. Based on the current understanding of hydrocarbon biodegradability, constituents in heavy fuel oils would be expected to biodegrade over time.

Summary : No additional testing is proposed. A technical discussion of hydrocarbon biodegradation based on reviews of available literature was incorporated in a robust summary format.

EVALUATION OF EXISTING ECOTOXICIT Y DATA AND PROPOSED TESTING

Various ecotoxicity studies on heavy fuel oils have been reported using different means of test substance exposures. These have been reviewed and reported by CO NCAWE (1998). For the assessment of ecotoxicity of poorly water soluble mixtures of hydrocarbons as found in petroleum products, the generally accepted procedure is to report results expressed in terms of th e "loading rate" (OECD, 2000). The loading rate is defined as the amount of the product that is equilibrated wi th the aqueous test medium, and the aqueous phase at equilibrium is termed the water-accommodated fraction (WA F) for the specific loading rate. Toxicological endpoints such as the LL50 or EL50 are used to express t he loading rate of the product lethal to or produce a specific effect in 50% of the test organisms. Ex posures may be prepared as oil-water dispersions (OWDs),June 17, 2004 Page 25 of 44 Heavy Fuel Oils Consortium Registration # 1100997

•

•

• where the insoluble petroleum fractions remain in t he exposure solutions. This method also results in an expression of the concentration of the applied product (i .e., mg test substance/l), but the methodology does not prevent potential adverse effects to the organisms due to physical entrapment. Small species appear to be more susceptible than large species. Water-soluble fracti ons (WSFs) and their dilutions also may be reported in ecotoxicity studies. Ecotoxicity endpoints based on wate r-soluble fractions have been reported to range from 0.9 mg/l to >4.5 milligrams total petroleum hydrocarbons (TPH)/l (MacLean and Doe, 1989; Jokuty et al., 2002). These preparations are expressed in terms of the measur ed concentrations of hydrocarbons in solution but do not allow the ecotoxicity of the product to be expressed in terms of the amount of that product required to produce a particular effect. Such results are not comparable to results obtained under WAF or OWD preparation methods.

For the assessment of the ecotoxicity of heavy fuel oils , the category substances are considered as a single group, and the potential for any category member to elicit adverse effects in aquatic organisms is attributed to the solubility of the constituent hydrocarbons in that member. This is valid because petroleum hydrocarbons elicit effects through a common mode of toxicity te rmed non-polar narcosis (Pet erson, 1994; van Wezel and Opperhuizen, 1995), which is produced by the soluble hy drocarbon fractions in aqueous preparations. Fuels having molecular weight hydrocarbons predominately higher than the solubility “cut-off” for acute toxicity show no measurable acute toxicity (CONCAWE, 2001). The solub ility cut-off varies with the hydrocarbon structure; thus, for paraffinic hydrocarbon s the solubility cut-off occurs at about C 10, while for alkylben zenes it is about C14 (CONCAWE, 2001). Other individual components contri bute to toxicity, but as molecular weight increases, solubility declines, as does toxicity.

Petroleum streams in the heavy fuel oil category genera lly consist of hydrocarbon molecules having 20 to 50 carbon atoms, although some streams in this category have lo w-end carbon atoms from 7 to 15. Heavy fuel oils also may be blended with gas oils or similar low viscosit y fuels to meet market specifications. This makes a highly heterogeneous group of petroleum substances that spans a wide range of molecular weight fractions. Based on distillation and carbon number ranges of t he category members, existing data on heavy fuel oil ecotoxicity may not represent the ecot oxicity of category members that contain a relatively high proportion of hydrocarbons below the solubility cut-off for acute toxi city (i.e., those having hydr ocarbons with low-end carbon numbers of 7 to 15 and low initial boiling points). In spit e of the heterogeneity of the heavy fuel oil category, the constituents in heavy fuels are generic hydrocarbon structur es (e.g., saturates, arom atics, etc.) represented in other petroleum HPV categories. Therefore, the Te sting Group proposes to use ecotoxicity data from the following HPV categories to read-across to cover the lightest heavy fuel oil streams:

Referenced data cited in the Kerosene/Jet Fuel Test Plan and robust summaries (API, 2003a), Referenced data cited in the Gas Oils Test Plan and robust summaries (API, 2003b), and Data generated from the proposed testing of select gas oils streams high in saturated and aromatic hydrocarbons.

Kerosenes and jet fuels are composed of saturated a nd aromatic hydrocarbon com pounds having structures and molecular weights similar to the light-end components in heavy fuel oils. Hence, the ecotoxicity of those substances provides conservative estimates of the ecotox icity of the lightest heavy fuel oils. Blended heavy fuel oils also contain a fraction of heterocyclic compounds that show solubility and molecular weight relationships similar to other hydrocarbons (i.e., solubility decreases with increasing molecular weight). Th ese compounds may contribute to aquatic toxicity, and their contribution is integrated in the current heavy fuel oil test data. When all ecotoxicity data sets are combined, the ranges of endpoint values are expected to cover the potential ecotoxicity of all category members of the heavy fuel oil category that contain various fractions of saturated, aromatic, and heterocyclic compounds.

Robust summaries for kerosene and gas oils ecotoxicity data cited below may be found in the HPV submissions for Kerosenes/Jet Fuel Test Plan (API, 2003a) and Gas Oils Test Plan (API, 2003b).

Acute Toxicity to Fish Data for heavy fuel oils showed slight or no acute toxici ty to fish when tested as either WAFs or OWDs. Shell (1997a,b) tested WAFs of a “light” and a “heavy” resi dual fuel oil (CAS No. 68476-33-5) and found the 96-hour LL50s for exposures to rainbow trout (Oncorhynchus my kiss) to be between 100 mg/l and 1000 mg/l for theJune 17, 2004 Page 26 of 44 Heavy Fuel Oils Consortium Registration # 1100997

“heavy” residual fuel oil and >1000 mg/l for the “light” re sidual fuel oil. Mobil (1987a) obtained a 96-hour LL50 of >10,000 mg/l when bluegill (Lepomis macrochirus) were exposed to OWDs of No. 6 fuel oil.

Fish LL50 values for kerosene/jet fuel tested as WAFs were between 10 mg/l and 100 mg/l (API, 2003a). LL50 values for distillate fuels cited in the gas oil HPV test plan ranged from 3.2 to 65 mg/l (API, 2003b).

Acute Toxicity to Aquatic Invertebrates Data for invertebrates (Daphnia magna) showed a similar ra nge of sensitivities as fish. In testing WAFs of the “light” and “heavy” residual fuels, Shell (1997c,d) found the EL50 of the “light” to be >1000 mg/l while that of the “heavy” to between 220 mg/l and 460 mg/l. Mobil (1987b) exposed daphnids to solutions in which oil was

coated on the inside surface of the test vessels. Ex posures done in this manner resulted in no immobilized daphnids at the maximum loading rate of 10,000 mg/l.

Invertebrate EL50 values for kerosene/jet fuel tested as WAFs were ranged 1.4 mg/l to <89 mg/l (API, 2003a). EL50 values for distillate fuels cited in the gas oil H PV test plan ranged from 2.0 to <300 mg/l (API, 2003b).

Toxicity to Algae Shell (1997e,f) reported the EL50 values based on gr owth rate and biomass for 72-hour exposures of Raphidocelis subcapitata to a “light” and a “heavy” residual fuel oil. Tests were run in sealed vessels without headspace. For the “light” material, the ELr50 (rate-based) was concluded to lie between 100 mg/l and 300 mg/l while the ELb50 (biomass-based) was between 3 mg/l and 10 mg/l. This contrasted somewhat with toxicity endpoints for the “heavy” residual fuel oil. Those tests gave ELr50 and ELb50 values of between 30 mg/l and 100 mg/l. Mobil (1987c) coated the surface of test flasks with No. 6 fuel oil and measured algal (R. subcapitata) biomass over 96 hours. Tests vessels were plugged with cotton, but otherwise allowed air exchange. Growth inhibition at the maximum loading rate of 10,000 mg/l was 47.5%, but the authors co ncluded that the ELb50 was >5,000 mg/l. Inhibition of 22% to 27% occurred in th e lowest three test levels, and the authors suggested physical obstruction of light penetrati on may have affected cell growth.

In 96-hour exposures using WAFs of kerosene, EL50 values ranged from 5.0 to 6.2 mg/l when based on inhibition of growth rate, and ranged from 5.9 mg/l to 11 mg/l when based on biomass (API, 2003a). In 72-hour WAF exposures, EL50 values based on growth rate and bi omass fell within the range of 10 mg/l to 30 mg/l (API, 2003a).

Algae exposed to WAFs of distillate fuels produced 72-hou r EL50 values based on growth rate that ranged from 2.2 to <46 mg/l, while values based on algal biomass ranged from 1.8 to 25 mg/l (API, 2003b).

The heavy fuel oil, kerosene, and gas oil ecotoxicity data described above are listed in the following Table 2. Together, these data encompass values that represent the potential toxicity of all members in the Heavy Fuel Oil HPV category.

Table 2. Ecotoxicity Data for Heavy Fu el Oil, Kerosene/Jet Fuel Oil, and Gas Oil.

Species Material Exposure

Type Effect / concentration

(mg/l) Reference

FISH

Heavy Fuel OilJune 17, 2004 Page 27 of 44 Heavy Fuel Oils Consortium Registration # 1100997

Rainbow trout

(Oncorhynchus mykiss)

Rainbow trout

(O. mykiss)

Bluegill

(Lepomis macrochirus) CAS No. 68476-33-5 (light)

residual fuel oil

CAS No. 68476-33-5 (heavy) residual fuel oil

No. 6 fuel oil WAF

WAF

OWD 96-h LL50 = >1000

96-h LL50 = 100 – 1000

96-h LL50 = >10,000 Shell, 1997a

Shell, 1997b

Mobil, 1987a

Kerosene/Jet Fuel

Various species Various WAF 96-h LL50 =

18

20

10 – 100

25 API, 2003a

Gas Oil

Various species Distillate fuels WAF 96-h LL50 =

57

3.2

6.6

57

21

65 API, 2003b

INVERTEBRATES

Heavy Fuel Oil

Daphnia magna

D. magna

D. magna CAS No. 68476-33-5 (light)

residual fuel oil

CAS No. 68476-33-5 (heavy) residual fuel oil

No. 6 fuel oil WAF

WAF

OWD 48-h EL50 = >1000

48-h EL50 = 220 – 460

48-h EL50 = >10,000 Shell, 1997c

Shell, 1997d

Mobil, 1987b

Kerosene/Jet Fuel

D. magna Various WAF 48-h EL50 =

21

1.4

40 – 89

1.9 API, 2003a

Gas OilJune 17, 2004 Page 28 of 44 Heavy Fuel Oils Consortium Registration # 1100997

D. magna Distillate fuels WAF 48-h EL50 =

7.8

5.3

14

42

2.0

210

68

13

100 – 300

13

6.4

36

9.6 API, 2003b

ALGAE

Heavy Fuel Oil

Raphidocelis subcapitata

R. subcapitata

R. subcapitata CAS No. 68476-33-5 (light)

residual fuel oil

CAS No. 68476-33-5 (heavy) residual fuel oil

No. 6 fuel oil WAF

WAF

OWD 96-h ELr50 = 100 – 300

96-h ELb50 = 3 – 10

96-h ELr50 = 30 – 100

96-h ELb50 = 30 – 100

96-h ELb50 = >5,000 Shell, 1997e

Shell, 1997f

Mobil, 1987c

Kerosene/Jet Fuel

R. subcapitata Various WAF 96-h ELr50 =

6.2

5.0

96-h ELb50 =

11

5.9

72-h ELr50 =

10 – 30

72-h ELb50 =

10 – 30 API, 2003aJune 17, 2004 Page 29 of 44 Heavy Fuel Oils Consortium Registration # 1100997

Gas Oil

R. subcapitata Distillate fuels WAF 72-h ELr50 =

2.9

2.2

78

22

22 – 46

72-h ELb50 =

1.8

2.2

25

10

10 – 22 API, 2003b

WAF = Water Accommodated Fraction

OWD = Oil-Water Dispersion

Summary. No further testing is proposed. The ecotoxicity data for heavy fuel oils combined with data for kerosene/jet fuel and gas oils HPV categories provides a range of ecotoxicity endpoints expected to encompass the ecotoxicity of all members of t he heavy fuel oils HPV category.June 17, 2004 Page 30 of 44 Heavy Fuel Oils Consortium Registration # 1100997

MATRIX OF AVAILABLE DATA AND PROPOSED TESTING

Table 3. Matrix of Available Data and Proposed Testing

R EFINERY Streams Subcategories Finished

Residual

Fuels

T ESTAtmosphericResidueAtmosphericDistillateVacuumResidueVacuumDistillateCrackedResidueCrackedDistillateReformerResidueResidual FuelOil

Physical/Chemical Properties 7

Melting Point 

### Ad

Boiling Point 

### Ad

Vapor Pressure 

### Ad

Water Solubility 

### Ad
Partition coefficient (log Kow) Ad

Ecotoxicity 7

Algae Growth Inhibition RA 9

Acute Freshwater Invertebrate RA 9

Acute Freshwater Fish RA 9

Environmental Fate 7

Biodegradation 

### Ad

Stability in Water 

### NA

Photodegradation (estimate) 

### Ad

Transport and Distribution 

### Ad

Mammalian Toxicity

Acute Ad RA 1 RA 2 Ad Ad Ad RA 3 Ad Repeat-dose Ad Ad Ad 2 Ad Ad Ad Test 5 Ad Reprod/Develop Ad Ad Ad Ad Ad Ad Test 5 Test 6

Genotoxicity, in vitro Test 8 Test 8 Ad Ad Ad Test 8 Test 8 Test 8

Genotoxicity, in-vivo RA 4 RA 1 RA 2 Ad Ad RA 4 RA 4 RA 4

Ad = Adequate, indicates adequate existing data. NA = Not Applicable, t he endpoint is not applicable” due to inherent physical and/or chemical properties. A technical discussion was developed to address such endpoints.

1 read across from API HPV Gas Oils Test Plan

2 read across from API HPV Asphalt Test Plan

3 read across from API HPV Aromatic Extracts Test Plan Test Plan

4 read across from in-vitro genotoxicity assay

5 OECD 422 repeat dose/reprodu ctive/developmental screen

6 OECD 421 reproductive/developmental screen

7 For the assessment of the physica l/chemical properties, ecotoxic ity, and environmental fate, the

category substances are considered as a single gr oup, and the potential for any category member to elicit adverse effects in aquatic organisms is attribut ed to the solubility of t he constituent hydrocarbons

in that member

8 Modified Ames & in vitro chromosomal aberration (OECD 473).June 17, 2004 Page 31 of 44 Heavy Fuel Oils Consortium Registration # 1100997

REFERENCES

API (American Petroleum Institute). 1980a. Acute toxi city tests API 78-6 #6 Heavy fuel oil (API gravity

11.7/2.7%S. API Med. Res. Publ. 27-32814, Washington D.C.

API (American Petroleum Institute). 1980b. Acute toxi city tests API 78-7 #6 Heavy fuel oil (API gravity

17.1/0.8%S. API Med. Res. Publ. 27-32774, Washington D.C.

API (American Petroleum Institute). 1980c. Acute toxi city tests API 78-8 #6 Heavy fuel oil (API gravity

23.1/0.2%S. API Med. Res. Publ. 27-32816, Washington D.C.

API (American Petroleum Institute). 1980d. Acute toxi city tests API 79-2 #6 Heavy fuel oil (API gravity

5.2/1.2%S. API Med. Res. P ubl. 27-32813, Washington D.C.

API (American Petroleum Institute). 1982. Acute toxicity studies catalytically cracked clarified oil Sample 81-

15. API Med. Res. Publ. 30-31854, Washington D.C.

API (American Petroleum Institute). 1984. Dermal se nsitization study in guinea pigs closed patch technique

Catalytic cracked clarified oil API sample 81-15. API Med. Res. Publ. 31-31417, Washington D.C.

API (American Petroleum Institute). 1985a. CHO/HGP RT Mammalian cell forward gene mutation assay of API

81-15. API Med. Res. Publ. 32-32118, Washington D.C.

API (American Petroleum Institute). 1985b. Evaluati on of the potential of RO-1, 81-15 and PS8-76D5-SATto

induce unscheduled DNA synthesis in primary rat he patocyte cultures. API Med. Res. Publ. 32-32407, Washington D.C.

API (American Petroleum Institute). 1985c. Evaluati on of the potential of RO-1, 81-15, and PS8-76D-SATto

induce unscheduled DNA synthesis in the in vivo-in vitro hepatocyte DNA repair assay. API Med. Res. Publ. 32-32406, Washington D.C.

API (American Petroleum Institute). 1985d. In vivo sister chromatid exchange assay API 81-15, catalytically

cracked clarified oil (CAS 64741-62-4). API Med. Res. Publ. 32-32254, Washington D.C.

API (American Petroleum Institute). 1985e. Mutagenicity evaluation studies in the rat bone marrow cytogenetic

assay in the mouse lymphoma forward mutation assay catalytic cracked clarified oil API sample 81-15. API Med. Res. Publ. 32-30534, Washington D.C.

API (American Petroleum Institute). 1985f. Sister ch romatid exchange assay in Chinese Hamster Ovary (CHO)

cells. Catalytic cracked clarified oil; API sample 81-15 CAS 64741-62-4. API Med. Res. Publ. 32-32750, Washington D.C.

API (American Petroleum Institute). 1986b. Morphological transformation of BALB/3T3 Mouse embryo cellsAPI

81-15, Catalytically cracked clarified oil (CAS 64741-62- 4). API Med. Res. Publ. 33-32638, Washington D.C. API (American Petroleum Institute). 1986c. Salmonella /Mammalian-microsome plate incorporationmutagenicity

assay (Ames test). API Med. Res. Publ. 33-30599, Washington D.C.

API (American Petroleum Institute). 1987. Comprehen sive Analytical Analysis of API generic petroleum

streams. American Petroleum Institute, Washington, DC.

API (American Petroleum Institute). 1989. Lifetime dermal carcinogenesis/chronic toxicity screening bioassay

of refinery streams in C3H/HeJ mice (AP-135r). API Med. Res. Publ. 36-31364, Washington D.C.

API (American Petroleum Institute). 2003a. Test Plan for HPV Category: Kerosene/Jet Fuel. Submitted to the

U. S. Environmental Protection Agency for the High Pr oduction Volume (HPV) program. API, Washington, DC.June 17, 2004 Page 32 of 44 Heavy Fuel Oils Consortium Registration # 1100997

API (American Petroleum Institute). 2003b. Test Plan for HPV Category: Gas Oils. Submitted to the U. S.

Environmental Protection Agency for the High Product ion Volume (HPV) program. API, Washington, DC.

Argus. 1992. Screening test for reproductive toxi city of F-179 administered percutaneously to Crl: CD  BR

VAF/Plus  male rats. Protocol 1001-002. Report No. AT X-91-0040. Argus Research Laboratory, Horsham,

PA.

Anderson, J.W., J.M. Neff, B.A. Cox, H.E. Tatem, and G.M. Hightower. 1974. Characteristics of dispersions

and water-soluble extracts of crude oil and refined oils and their toxicity to estuarine crustaceans and fish. Marine Biology. 27:75-88. [as cited in Jokuty et al., 2002]

ASTM (American Society for Testing and Materials). 1999. Standard Test Method for Pour Point of Petroleum

Oils. ASTM D97, Volume 05.01. West Conshohocken, PA.

ASTM (American Society for Testing and Materials). 2002. Standard Specification for Fuel Oils. ASTM D396.

West Conshohocken, PA.

ASTM (American Society for Testing and Materials). 2003. Liqu id fuels - Fuel oils - Part 3: Fuel oil S; Minimum

requirements. West Conshohocken, PA. Bartha, R. and R.M. Atlas. 1977. The microbiology of aquatic oil spill s. Adv. Appl. Microbiol. 22:225-266.

CONCAWE. 1998. Heavy fuel oils. Product dossier No. 98/109. Brussels. 48 pp.

CONCAWE. 2001. Environmental Classification of Petroleum Substances – Summary Data and Rationale.

Report no. 01/54. Brussels. 134 pp.

CONSCI (Consolidated Sciences, Inc.). 1992a. Cert ificate of Analysis No. 21012010. Pasadena, Texas.

CONSCI (Consolidated Sciences, Inc.). 1992b. Cert ificate of Analysis No. 21012014. Pasadena, Texas.

CONSCI (Consolidated Sciences, Inc.). 1993a. Cert ificate of Analysis No. 30330004. Pasadena, Texas.

CONSCI (Consolidated Sciences, Inc.). 1993b. Cert ificate of Analysis No. 30330008. Pasadena, Texas.

CONSCI (Consolidated Sciences, Inc.). 1993c. Cert ificate of Analysis No. 30330013. Pasadena, Texas.

CONSCI (Consolidated Sciences, Inc.). 1993d. Cert ificate of Analysis No. 30330016. Pasadena, Texas.

Cruzan, G., Low, L. K., Cox, G. E., Mee ks, J. R., Mackerer, C. R., Craig, P. H., Singer, E. J. and Mehlman, M. A.

1986. Systemic toxicity from subchronic dermal exposu re, chemical characterization, and dermal penetration of catalytically cracked clarified slurry oil. Tox. and Ind. Health Vol 2, No. 4, pp 429-444.

DataChem Laboratories. 1990. Characterization of Test Article F-92-01. Task Order No. 86-010. Salt Lake

City, UT.

ECB (European Chemicals Bureau). 2000. European Chemical Substances Information System (ESIS),

IUCLID Dataset, Residual Fuel Oils (CAS No. 64741-62-4). Web version URL: http://ecb.jrc.it/

.

EPA (U.S. Environmental Prot ection Agency). 1999. Guidance for Assessing Adequacy of Existing Data,

http://www.epa.gov/chemrtk/guidocs.htm.

EPA (U.S. Environmental Protection Agency). 2001. EPI (Estimation Programs Interface) Suite, V3.10, Subroutine AOPWIN, V1.90. Office of Pollution Prevention and Toxics, Washington, DC.

EPA (U.S. Environmental Prot ection Agency). 2004. Substance re gistry system (SRS) Database U.S.

Environmental Protection Agency. http://www.epa.gov /srs/index.htm.June 17, 2004 Page 33 of 44 Heavy Fuel Oils Consortium Registration # 1100997

Fasnacht, M.P. and Blough, N.V. 2002. Aqueous photodegradation of polyc yclic aromatic hydrocarbons.

Environ. Sci. Technol. 36:4364-4369.

Feuston, M. H., Low, L. K., Hamilton, C. E. and Ma ckerer, C. R. 1994. Correlation of systemic and

developmental toxicities with chemical component classes of refinery streams. Fundamental and Applied Toxicolgy Vol 22 pp 622-630.

Garrett, R.M., Haith, C.E., Prince, R.C., and Pickering, I.J. 1998. Phot ooxidation of polycyclic aromatic

hydrocarbons in crude oils. In: Proceedings of the 21 st Arctic and Marine Oil Spill Program. (AMOP) Technical Seminar. Environment Canada, Ottawa, Ont., pp. 99-114.

Garrett, R.M., Rothenburger, S.J., and Pr ince, R.C. 2003. Biodegradation of fuel oil under laboratory and arctic

marine conditions. Spill Sci. Technol. Bull. 8(3): 297-302.

Gary, J. H. and Handwerk. G. E. 1994. Petroleum Refining Technology and Economics, Third Ed. Chapter 10

p.202.

Harris, J.C. 1982. Rate of Hydrolysis. In Handbook of Chemical Property Estimation Methods. Lyman, Reehl

and Rosenblatt, eds. McGraw-H ill Book Co., New York.

Hoberman, A. M., Christian, M. S., Lovre,S., Roth, R. And Koschier, F. 1995. Developmental toxicity study of

clarified slurry oil (CSO) in the rat. Fundam ental and Apllied Toxicology, vol. 28, pp 34-40.

IARC (International Agency for Research on Cancer). 1989. Monographs on the evaluation of the carcinogenic

risk of chemicals to humans. Volume 45: Occupationa l exposures in petroleum refining; crude oil and major petroleum fuels. Lyon, France

Jezequel, R., L. Menot, F. X. Merlin, and R.C. Prince. 2003. Natural cleanup of heavy fuel oil on rocks: an in

situ experiment. Mar. Pollut. Bull. 46: 983-990.

Jokuty, P., Whiticar S., Wang Z., Fingas M., Fieldhouse B ., Lambert P., and Mullin J. 2002. Properties of Crude

Oils and Oil Products. Environmental Protection Servic e, Environment Canada, Ottawa, Ontario. Internet Version 2002, URL: http://www.etcentre.org/spills

.

Leahy, J.G., And R.R. Colwell. 1990. Microbial degradat ion of hydrocarbons in the environment. Microbiol.

Rev. 54:305-315.

Lee, K., R.C. Prince, C.W. Greer, K.G. Doe, J.E.H. Wilson, S.E. Cobanli, G.D. Wohlgeschaffen, D. Alroumi, T.

King, and G.H. Tremblay. 2003. Composition and toxicity of residual Bunker C fuel oil in intertidal sediments after 30 years. Spill Sci. Te chnol. Bull. 8(2): 187-199.

MacLean, M.M. and Doe, K.G. 1989. The comparative to xicity of crude and refined oils to Daphnia magna and Artemia. Manuscript Report EE-111, Environment Canada, Ottawa, On. 72 pp.

Mc Kee, R.H. , Nicolich, M.J., Scala, R. A., and Lew is, S.C. 1990. Estimation of epidermal carcinogenic potency. Fundamental and Applied Toxicology, vol. 15, pp 320-328.

Mobil. 1985a. A modified ames pre-incubation mutagenesi s assay for determination od specific mutagenicity of the DMSO extract of heavy vacuum gas oil. Study No. 52261. Mobil Environmental and Health Science Laboratory, Princeton, NJ.

Mobil. 1985b. Thirteen-week toxicity study by dermal applic ation of clarified slurry oil (CSO) to rats. Study No.

20525. Mobil Environmental and Health Science Laboratory, Princeton, NJ.

Mobil. 1987a. A Static 96-hour Acute Toxicity Study of Process Oil to Bluegill Sunfish. Mobil Environmental and Health Science Laboratory, Pennington, NJ.June 17, 2004 Page 34 of 44 Heavy Fuel Oils Consortium Registration # 1100997

Mobil. 1987b. A Static 48-hour Acute Toxicity Study of Process Oil to Daphnia magna. Mobil Environmental

and Health Science Laboratory, Pennington, NJ.

Mobil. 1987c. A Static 96-hour Acut e Toxicity Study of Process Oil to Selenastrum capricornutum . Mobil

Environmental and Health Science Laboratory, Pennington, NJ.

Mobil. 1987d. Developmental toxicity screen in rat expos ed dermally to Heavy coker gas oil-2. Report of study

No. 50431. Mobil Environmental and Health Science Laboratory, Princeton, NJ.

Mobil. 1987e. Metaphase analysis of chinese hamster ov ary (CHO) cells treated in vitro with a DMSO extract

of heavy vacuum gas oil (a screening assay). Study No. 52262. Mobil Environmental and Health Science Laboratory, Princeton, NJ. [Cited in CONCAWE (2000) IUCLID data set]

Mobil. 1987f. Micronucleus assay of bone marrow red bl ood cells from rats treted via dermal administration of

heavy vacuum gas oil. Study No. 61591. Mobil Envir onmental and Helath Science Laboratory, Princeton, NJ.

Mobil. 1988a. Consolidated acute test report on heavy vacuum gas oil. Study Nos. 62443, 62444, 62445.

Mobil Environmental and Health Science Laboratory, Princeton, NJ.

Mobil. 1988b. Consolidated acute test report on V/br eaker HGO. Study Nos. 62496, 62497, 62498, 62499.

Mobil Environmental and Health Science Laboratory, Princeton, NJ.

Mobil. 1988c. Consolidated acute test report on vi s gas oil VIBRA. Study Nos. 62500, 62501, 62502, 62503. Mobil Environmental and Health Science Laboratory, Princeton, NJ.

Mobil. 1988d. Thirteen-week dermal administration of heavy vacuum gas oil to rats. Study No. 61590. Mobil Environmental and Health Science Laboratory, Princeton, NJ.

Mobil. 1991. Developmental toxicity study in rats ex posed dermally to heavy atmospheric gas oil. Study No.

64146. Mobil Environmental and Health Science Laboratory, Princeton, NJ.

Mobil. 1992a. Consolidated acute test report on V.B. Mittelol. Study Nos. 64635, 64636, 64637, 64638. Mobil

Environmental and Health Science Laboratory, Princeton, NJ.

Mobil. 1992b. Thirteen-week dermal administration of visbreaker gas oil to rats. Study No. 63237. Mobil

Environmental and Health Sciences Laboratory, Princeton, NJ.

Mobil. 1992c. Thirteen-week dermal administration of heavy atmospheric gas oil to rats. Study No. 63456. Mobil Oil Corporation Environmental and Heal th Sciences Laboratory, Princeton, NJ.

Mobil. 1994. Thirteen-week dermal administration of Jolie t heavy coker gas oil to rats. Study No. 64165. Mobil

Environmetal and Health Science Laboratory, Princeton, NJ.

Mobil. 1995. Thirteen-week dermal administration of To rrance heavy coker gas oil to rats – 3. Study No.

64184. Mobil Environmental and Health Sciences Laboratory, Princeton, NJ.

Mobil. Undated. Developmental toxicity screen in rats exposed dermally to heavy vacuum gas oil (HVGO):

Final report. Study No. 61801. Mobil Environmental and Health Sciences Laboratory, Princeton, NJ.

Mulkins-Phillips, G.J., and J.E. Stewar t. 1974. Effect of environmental par ameters on bacterial degradation of

Bunker C oil, crude oils and hydrocar bons. App. Microbiol. 28(6): 915-922.

NIPER (National Institute for Petroleum and Energy Resear ch). 1993a. Analyses of ARCO Petroleum Stream

Samples. Bartlesville, Oklahoma.June 17, 2004 Page 35 of 44 Heavy Fuel Oils Consortium Registration # 1100997

NIPER (National Institute for Petroleum and Energy Resear ch). 1993b. Analyses of ARCO Petroleum Stream

Samples: Set II. Ba rtlesville, Oklahoma.

NOAA (National Oceanic and Atmospheric Administration). 2004. Fact Sheet: Number 6 Fuel Oil (Bunker C)

Spills. Office of Response and Restoration, National Ocean Service, NOAA. Web URL: http://response.restoration.noaa.gov/oilaids/repo rts.html#fact

OECD (Organization for Economic Cooperation and Deve lopment). 1989. Guideline No. 117: Partition

Coefficient (n-octanol/water): High performance liq uid chromatography (HPLC) method, adopted 30 March 1989. In: OECD Guideline for Testing of Chemicals, Paris.

OECD (Organization for Economic Cooperation and Deve lopment). 1995. Guideline No. 107: Partition

Coefficient (n-octanol/water): Shake flask method, adopted 27 July 1995. In: OECD Guideline for Testing of

Chemicals. Paris.

OECD (Organization for Economic Cooperation and Development). 2000. Guidance Document on Aquatic

Toxicity Testing of Difficult Substances and Mixtures. ENV/JM/MONO (2000) 6. Environmental Health and Safety Publications Series on Testing and Assessment No. 23. Paris, September.

Peterson, D.R. 1994. Calculating the aquatic toxicity of hydrocarbon mixtures. Chemosphere. 29(2): 2493-

2506.

Potter, T.L. and Simmons K.E. 1998. Total petroleum hy drocarbon criteria working group series, Volume 2.

Composition of petroleum mixtures. Amherst Sci entific Publishers, Amherst, Massachusetts. 114 pp.

Prince, R.C. 2002. Petroleum and other hydrocarbons, biod egradation of. In: Bitton, G. (ed.), Encyclopedia of

Environmental Microbiology. John Wiley & Sons, New York, pp. 2402-2416.

Prince, R.C., R.M. Garrett, R.E. Bare , M.J. Grossman, T. Townsend, J.M. Suflita, K. Lee, E.H. Owens, G.A.

Sergy, J.F. Braddock, J.E. Lindstrom, and Lessard R.R.. 2003. The roles of photooxidation and biodegradation in long-term weathering of crude and heavy fuel oils. Spill Sci. Technol. Bull. 8(2): 145-156.

Quann, R.J. and S.B. Jaffe. 1992. Structure-oriented lumping: Desc ribing the chemistry of comples

hydrocarbon mixtures. Ind. Eng. Chem. Res. 31(11):2483-2497.

Rashid, M.A. 1974. Degradation of Bunker C oil under different coastal environments of Chedabucto Bay,

Nova Scotia. Est. and Coastal Mar. Sci. 2:137-144.

Richmond, S.A., J.E. Lindstrom, and J.F. Braddock. 2001. Effects of chitin on microbial emulsification,

mineralization potential, and toxicity of Bunker C fuel oil. Mar. Poll. Bull. 42(9): 773-779.

Saeger, R.B. and Jaffe S.B. 2002. Petroleum stream compositional modeling for the petroleum HPV testing

group program. ExxonMobil Process Rese arch Laboratories, Paulsboro, NJ.

Shell. 1997a. Light fuel oil: Acute to xicity of water accomodated fractions to Oncorhynchus mykiss . Study

OP.97.47001, Shell Research and Technology Centre, Thornton, UK.

Shell. 1997b. Heavy fuel oil: Acute to xicity of water accomodated fractions to Oncorhynchus mykiss . Study

OP.97.47002. Shell Research and Technology Centre, Thornton, UK.

Shell. 1997c. Light fuel oil: Acute to xicity of water accomodated fractions to Daphnia magna . Study

OP.97.47001. Shell Research and Technology Centre, Thornton, UK.

Shell. 1997d. Heavy fuel oil: Acute to xicity of water accomodated fractions to Daphnia magna . Study

OP.97.47002. Shell Research and Technology Centre, Thornton, UK.June 17, 2004 Page 36 of 44 Heavy Fuel Oils Consortium Registration # 1100997

Shell. 1997e. Light fuel oil: Acute to xicity of water accomodated fractions to Raphidocelis subcapitata . Study

OP.97.47001. Shell Research and Technology Centre, Thornton, UK.

Shell. 1997f. Heavy fuel oil: Acute to xicity of water accomodated fractions to Raphidocelis subcapitata . Study

OP.97.47002. Shell Research and Technology Centre, Thornton, UK.

Shiu, W.Y., M. Bobra, A.M. Bobra, A. Maijanen, L. Su ntio, and Mackay D. 1990. The water solubility of crude

oils and petroleum products. Oil & Chem. Poll. 7:57-84.

Sinclair Oil Corporation. Material Safety Data Sheet, Residual Fuel Oil, Vacuum Tower Bottoms. Salt Lake City,

Utah.

Smith, W.E., Sunderland, D.A., and Sugiura, K. 1951. Experimental analysis of the carcinogenic activity of certain petroleum products. Arch Ind Hyg Occup Med 4: 299-314.

Speight, J. G. 1998. Petroleum Chemistry and Refini ng. Applied Energy Technology Series. Taylor and

Francis, Washington, D.C.

Suntio, I., W.Y. Shiu, and D. Mackay. 1986. Analyses of water soluble fractions of crude oils and refined

products: a study of solubility of selected oils in water, Contract No. 0164, Environment Canada, Ottawa, On. [as cited in Jokuty et al., 2002]

TFMM (Texaco Fuel and Marine Marketing). 2001. Material Safety Data Sheet, 29068 Fuel Heavy 380 CST.

Houston, Texas.

Total UK Limited. 2003. Material Safety Data Sheet No . TS-MSDS 3, residual fuel oils. Watford, Herts, United

Kingdom.

Trent University. 1999. Level 1: Fugacity-based environmental equilibrium partitioning model. Environmental

Modeling Centre, Trent University, Peterborough, Ontario.

UBTL (Utah Biomedical Testing Laboratory Inc.). 1986. Dermal sensitization study in guinea pigs administered

heavy fuel oil. Report No. ATX-85 -0158. Salt Lake City. UT.

UBTL (Utah Biomedical Test Laboratory, Inc.). 1987. 28 day dermal toxicity study in rats on Watson Heavy Fuel Oil. Report No. ATX-86-0008. Salt Lake City UT.

UBTL (Utah Biomedical Testing Laboratory Inc.). 1988. Ac ute oral toxicity study in rats administered F-97-01.

Report No. ATX-88-0086, study No. 64707. Salt Lake City, UT

UBTL (Utah Biomedical Testing Laboratory Inc.). 1989a. Acute dermal toxicity study (limit test) in rabbits

administered test article F-97-01. Study No. 64834. Report No. ATX-88-0087. Salt Lake City, UT

UBTL (Utah Biomedical Testing Laboratory Inc.). 1989b. Dermal sensitization study in guinea pigs

administered test article F-97-01 (Coker heavy gas oil). Study No. 64838. Report No. ATX-88-0090. Salt Lake City UT.

UBTL (Utah Biomedical Testing Laboratory Inc.). 1989c. Dermal sensitization study in guinea pigs

administered test article F-98-01 (Vacuum tower botto ms. Study No. 65066. Report No. ATX-88-0097. Salt Lake City UT. UBTL (Utah Biomedical Testing Laboratory Inc.). 1989d. Primary dermal irritation study in rabbits administered test article F-97-01 (Coker heavy gas oil). Study No. 64782. Report No. ATX-88-0089. Salt Lake City UT.

UBTL (Utah Biomedical Testing Laboratory Inc.). 1989e. Primary dermal irritation study in rabbits

administyered test article F-98-01 (Vacuum tower bottoms ). Study No. 65054. Report No. ATX-88-0096. Salt Lake City UT.June 17, 2004 Page 37 of 44

Heav y F uel Oils Consortium Regi stration # 11009 97

UBTL (Utah Biomedi cal T e sting L abo ra tory Inc.). 1989f. Primary eye irritation study in rab b i t s admini s tered test

article F

- 97 -0 1 (Co k e r he a vy gas oil). Study No. 648 31. Repo rt No. ATX-88-00 88. Salt Lake City UT.

UBTL (Utah Biomedi cal T e sting L abo ra tory Inc.). 1989g. Primary eye irritation study in rab b i t s admini s tered

test articl e F-98-0 1 (Va c uu m tower b o ttoms). Study No. 65042. Re port No. ATX-88-0 095. Sal t Lake City UT.

UBTL (Utah Biomedi cal T e sting L abo ra tory Inc.). 1990a. 28 day derm a l toxicity study in rats. Repo rt No . ATX90-0 066. Sal t Lake City. UT.

UBTL (Utah Biomedi cal T e sting L abo ra tory Inc.). 1990b. Acute o r al toxicity stu d y in rats ad ministe r ed te st

article F

- 13 2. Repo rt No. ATX-90 -00 59. Salt Lake Cit y , UT.

UBTL (Utah Biomedi cal T e st Lab orato r y, Inc.) 1990 c. Derm al se nsitization stu d y in albino g u inea pi gs admini s tered test articl e F-113-01 (He a vy Vacuum Ga s Oil). Re port No. ATX-89-0035. Salt Lake City UT.

UBTL (Utah Biomedi cal T e sting L abo ra tory Inc.). 1991. Primary eye irritation study in rab b i t s admini s tered test

article F

- 13 2 (Atmosphe ric tower bottom s ). Study No. 65833. Re p o rt No. ATX-9 0 -00 61. Salt Lake City UT.

UBTL (Utah Biomedi cal T e sting L abo ra tory Inc.). 1992a. Acute d e rmal toxicity study (limit test) in ra bbits

admini s tered test articl e F-136. Study No. 65989. Re port No. ATX-90-0 092. Sal t Lake City, UT.

UBTL (Utah Biomedi cal T e sting L abo ra tory Inc.). 1992b. Acute d e rmal toxicity study in rab b i t s admini s tered

test articl e F-132.. Study No. 658 93. Repor t No. ATX-90-006 0. Salt Lake Cit y , UT.

UBTL (Utah Biomedi cal T e sting L abo ra tory Inc.). 1992c. De rmal sen s itization study in guin ea pig s

admini s tered test articl e F-132 (Atmo s p heri c towe r b o tto ms). Study No. 6584 9

. Report No. ATX-90 -006 3

. Salt Lake Cit y UT.

UBTL (Utah Biomedi cal T e sting L abo ra tory Inc.). 1992d. Primary dermal irritati on study in ra bbits

admini s tyere d test articl e F-13 2 (Atmo s pheri c tower bo ttoms). Study No. 658 4 1 . Report No . ATX-90-0 0 6 2

. Salt Lake Cit y UT.

UBTL (Utah Biomedi cal T e sting L abo ra tory Inc.). 1994. A developmental toxici ty scre en in female rats

admini s tered F-22 8 dermal l y during ge st ation days 0 t o 20. Study No. 66479. Re port No. ATX-91-0 267. Uta h

Biomedi cal T e st Lab orato r y, Inc., Salt Lake City UT

Van We zel, A.P. and A. Op perh u izen. 1995. Narco s i s Du e to Environm ental Po llutants in Aq uatic O r gani sms:

Re sidu e-Ba sed Toxicity, Mech ani sm s, and Memb ra ne Burd en s. Critical Revie w s in T o xicol ogy 25:255 -2 79.

Wal k er, J.D., L. Petraki s , and R.R. Colwell. 1976. Co mpa r ison of the biode gra d ability of crud e and fuel oil s

.

Can. J. Mi cro b iol. 22:598 -6 02.June 17, 2004 Page 38 of 44 Heavy Fuel Oils Consortium Registration # 1100997

APPENDIX A.

CAS Numbers and Definitions of Category Members

The CAS numbers and definitions of refinery streams, including those in the heavy fuel oils category, were developed in response to Section 8(b) of the Toxic S ubstances Control Act. This section of TSCA required identification and registration with the Environmental Protection Agency before July 1979 of each “chemical substance” being manufactured, processed, imported or distributed in commerce. Due to analytical limitations and known variability in refinery stream composition, identification of every specific individual molecular compound in every refinery process stream under all pr ocessing conditions was impossible. Recognizing these problems, the American Petroleum Institute (API) recommended to the EPA a list of generic names for refinery streams consistent with industry operations and cove ring all known processes used by refiners. The list, including generic names, CAS numbers and definition of each stream, was published by the EPA as “Addendum I, Generic Terms Covering Petroleum Refinery Process Streams.”

Because of the variability inherent in the processing of pet roleum materials, the definitions API developed for the CAS numbers are qualitative in nature, written in broad, general terms. The definitions often contain only ranges of values for carbon numbers, with little if any quantitative analytical informat ion or concern for possible compositional overlaps. As a result, the CAS descriptions are not useful in determining the exact composition of any specific refinery stream.

Residual Fuel Oils

68476-33-5 Fuel oil, residual The liquid product from various refinery streams, usually residues. The composition is complex and

varies with the source of the crude oil.

68553-00-4 Fuel oil, no. 6 A distillate oil having a minimum viscosity of 900 SUS at 37.7°C (100°F) to a maximum of 9000 SUS at 37.7°C (100°F).

Process Subcategories

Atmospheric Residual

64741-45-3 Residues (petroleum), atm. Tower A complex residuum from the atmospheric distillation of crude oil. It consis ts of hydrocarbons having carbon numbers predominantly greater than C20 and boiling above approximately 350 °C (662°F). This stream is likely to contain 5 wt % or more of 4- to 6-membered condensed ring aromatic hydrocarbons.

64742-78-5 Residues (petroleum), hydrodesulfurized atmospheric A complex combination of hydrocarbons obtained by treating an atmospheric tower residuum with hydrogen in the presence of a catalyst under conditions primarily to remove organic sulfur compounds. It consists of hydrocarbons having carbon numbers predominantly greater than C20 and boiling above approximately 350°C (662°F). This stream is likely to contain 5 wt % or more of 4- to 6-membered condensed ring aromatic hydrocarbons.

68333-22-2 Residues (petroleum), atmospheric A complex residuum from atmosphe ric distillation of crude oil. It consists of hy drocarbons havingJune 17, 2004 Page 39 of 44 Heavy Fuel Oils Consortium Registration # 1100997

carbon numbers predominantly greater than C11 and boiling above approximately 200°C (392°F). This stream is likely to contain 5 wt.% or more of 4- to 6-membered condensed ring aromatic hydrocarbons.

68607-30-7 Residues (petroleum), topping plant, low-sulfur A low-sulfur complex combination of hydrocar bons produced as the residual fraction from the topping plant distillation of crude oil. It is the re siduum after the straight-run gasoline cut, kerosene cut and gas oil cut have been removed.

70592-79-9 Residues (petroleum), atm. tower, light A complex residuum from the atmospheric distillation of crude oil. It consis ts of hydrocarbons having carbon numbers predominantly greater than C11 and boiling above approximately 200°C (392°F). This stream is likely to contain 5 wt % or more of 4- to 6-membered condensed ring aromatic hydrocarbons.

68476-32-4 Fuel oil, residues-straight-run gas oils, high-sulfur

NONE

Atmospheric Distillate

68410-00-4 Distillates (petroleum), crude oil A complex combination of hydroc arbons produced by di stillation of crude oil. It consists of hydrocarbons having carbon numbers predominantly in the range of C11 through C50 and boiling in the range of approximately 205°C to great er than 495°C (401°F to above 923°F).

68783-08-4 Gas oils (petroleum), heavy atmospheric A complex combination of hydrocarbons obtained by the distillation of crude oil. It consists of hydrocarbons having carbon numbers predominantly in the range of C7 through C35 and boiling in the range of approximately 121°C to 510°C (250°F to 950°F),

Residual

Vacuum Residual

68512-62-9 Residues (petroleum), light vacuum A complex residuum from the vacuum distillation of the residuum from the atmospheric distillation of crude oil. It consists of hydrocarbons having carbon numbers predominantly greater than C13 and boiling above approximately 230°C.

70913-85-8 Residues (petroleum), solvent-ext d. vacuum distilled atm residuum A complex residuum produced by the solvent extraction of the va cuum distillate of the complex residuum from the atmospheric distillation of crude oil.

Vacuum Distillate

64741-57-7 Gas oils (petroleum), heavy vacuum A complex combination of hydroc arbons produced by t he vacuum distillation of the residuum from atmospheric distillation of crude oil. It cons ists of hydrocarbons having carbon numbersJune 17, 2004 Page 40 of 44 Heavy Fuel Oils Consortium Registration # 1100997

predominantly in the range of C20 through C50 and boiling in the range of approximately 350°C to 600°C (662°F to 1112°F). This stream is likely to contain 5 wt. % or more of 4- to 6-membered condensed ring aromatic hydrocarbons.

64742-59-2 Gas oils (petroleum), hydrotreated vacuum A complex combination of hydrocarbons obtained by treating a petroleum fraction with hydrogen in the presence of a catalyst. It consists of hydroc arbons having carbon numbers predominantly in the range of C13 through C50 and boiling in the range of approximately 230°C to 600°C (446°F to 1112°F). This stream is likely to contain 5 wt % or more of 4- to 6-membered condensed ring aromatic hydrocarbons.

64742-86-5 Gas oils (petroleum), hydrodesulfurized heavy vacuum A complex combination of hydrocarbons obtained fr om a catalytic hydrodesulfurization process. It consists of hydrocarbons having carbon numbers predominantly in the range of C20 through C50 and boiling in the range of approximately 350°C to 600°C (662°F to 1112°F). This stream is likely to

contain 5 wt. % or more of 4- to 6-memb ered condensed ring aromatic hydrocarbons.

68955-27-1 Distillates (petroleum), pet roleum residues vacuum A complex combination of hydroc arbons produced by t he vacuum distillation of the residuum from the atmospheric distilla tion of crude oil.

70592-76-6 Distillates (petroleum), intermediate vacuum A complex combination of hydroc arbons produced by t he vacuum distillation of the residuum from atmospheric distillation of crude oil. It cons ists of hydrocarbons having carbon numbers predominantly in the range of C14 through C42 and boiling in the range of approximately 250°C to 545°C (482°F to 1013°F). This stream is likely to contain 5 wt.% or more of 4- to 6-membered condensed ring aromatic

70592-77-7 Distillates (petroleum), light vacuum A complex combination of hydroc arbons produced by t he vacuum distillation of the residuum from atmospheric distillation of crude oil. It cons ists of hydrocarbons having carbon numbers predominantly in the range of C11 through C35 and boiling in the range of approximately 250°C to 545°C (482°F to 1013°F).

70592-78-8 Distillates (petroleum), vacuum A complex combination of hydroc arbons produced by t he vacuum distillation of the residuum from atmospheric distillation of crude oil. It cons ists of hydrocarbons having carbon numbers predominantly in the range of C15 through C50 and boiling in the range of approximately 270°C to 600°C (518°F to 1112°F). This stream is likely to contain 5 wt.% or more of 4- to 6-membered condensed ring aromatic hydrocarbons.

Cracked Residual

64741-62-4 Clarified oils (petroleum), catalytic cracked (a lso listed in Olefins Panel Fuel Oils Category) A complex combination of hydrocarbons produced as the residual fraction from distillation of the products from a catalytic cracking process. It co nsists of hydrocarbons having carbon numbers predominantly greater than C20 and boiling above approximately 350°C (662°F). This stream is likely to contain 5 wt % or more of 4- to 6-membered condensed ring aromatic hydrocarbons.June 17, 2004 Page 41 of 44 Heavy Fuel Oils Consortium Registration # 1100997

64741-75-9 Residues (petroleum), hydrocracked A complex combination of hydrocarbons produced as the residual fraction from distillation of the products of a hydrocracking process. It cons ists of hydrocarbons having carbon numbers predominantly greater than C20 and boiling above approximately 350°C (662°F).

64741-80-6 Residues (petroleum), thermal cracked A complex combination of hydrocarbons produced as the residual fraction from distillation of the product from a thermal cracking process. It cons ists predominantly of unsaturated hydrocarbons having carbon numbers predominantly greater than C20 and boiling above approximately 350°C (662°F). This stream is likely to contain 5 wt % or more of 4- to 6-membered condensed ring aromatic hydrocarbons.

68187-58-6 Pitch, petroleum, arom

The residue from the distillation of thermal cr acked or steam-cracked re siduum and/or catalytic cracked clarified oil with a softening point from 40 degree C to 180 degree C (104 degree F to 356 degree.F). Composed primarily of a complex comb ination of three or more membered condensed ring aromatic hydrocarbons.

68478-17-1 Residues (petroleum), heavy coker gas oil and vacuum gas oil A complex combination of hydrocarbons produced as the residual fraction from the distillation of heavy coker gas oil and vacuum gas oil. It predomin antly consists of hydrocarbons having carbon numbers predominantly greater than C13 and boiling above approximately 230°C (446°F).

68783-13-1 Residues (petroleum) coker scrubber condensed-ring-aromatic-containing A very complex combination of hydrocarbons prod uced as the residual fraction from the distillation of vacuum residuum and the products from a therma l cracking process. It consists predominantly of hydrocarbons having carbon numbers predom inantly greater than C20 and boiling above approximately 350°C (662°F). This stream is likely to contain 5 wt. % or more of 4- to 6-membered condensed ring

Cracked Distillate

64741-61-3 Distillates (petroleum), heavy catalytic cracked A complex combination of hydrocar bons produced by the distillation of product s from a catalytic cracking process. It consists of hydrocarbons hav ing carbon numbers predominantly in the range of C15 through C35 and boiling in the range of approximately 260 °C to 500°C (500°F to 932°F). This stream is likely to contain 5 wt. % or more of 4- to 6-membered condensed ring aromatic hydrocarbons.

64741-81-7 Distillates (petroleum), heavy thermal cracked A complex combination of hydrocarbons from the di stillation of the products from a thermal cracking process. It consists predominantly of unsaturated hydrocarbons having carbon numbers predominantly in the range of C15 through C36 and boiling in the range of approximately 260°C to 480°C (500°F to 896°F). This stream is likely to contain 5 wt. % or more of 4- to 6-membered condensed ring aromatic hydrocarbons.

68333-26-6 Clarified oils (petroleum), hy drodesulfurized catalytic cracked A complex combination of hydrocarbons obtained by treating catalytic cracked clarified oil withJune 17, 2004 Page 42 of 44 Heavy Fuel Oils Consortium Registration # 1100997

hydrogen to convert organic sulfur to hydrogen sulfide which is removed. It consists of hydrocarbons having carbon numbers predom inantly greater than C20 and boiling above approximately 350°C (662°F). This stream is likely to contain 5 wt. % or more of 4- to 6-membered condensed ring aromatic hydrocarbons.

68333-27-7 Distillates (petroleum), hy drodesulfurized intermed iate catalytic cracked A complex combination of hydrocarbons obtai ned by treating intermediate catalytic cracked distillates with hydrogen to convert organic sulfur to hydrogen sulfide which is removed. It consists of hydrocarbons having carbon num bers predominantly in the range of C11 through C30 and boiling in the range of approximately 205°C to 450°C (401°F to 842°F). It contains a relatively large proportion of tricyclic aromatic hydrocarbons.

70955-17-8 Aromatic hydrocarbons, C12-20 A complex combination of hydrocarbons obtained from the distillation of biphenyl and naphthalene feedstocks. It consists predominantly of hydroc arbons having carbon numbers predominantly in the range of C12 through C20, such as alkylbenzenes, alkylnaphthalenes, indans, fluorenes, acenaphthalenes, phenanthrenes and anthracenes, and boiling in the range of approximately 282.degree.C to 427.degree.C (540.degree.F to 800.degree.F).

Reformer Residual

64741-67-9 Residues (petroleum), catalytic reformer fractionator A complex combination of hydrocarbons produced as the residual fraction from distillation of the product from a catalytic reforming process. It co nsists of predominantly aromatic hydrocarbons having carbon numbers predominantly in the range of C10 through C25 and boiling in the range of approximately 160 °C to 400°C (320°F to 725°F). This st ream is likely to contain 5 wt. % or more of 4- or 6-membered condensed ring aromatic hydrocarbons.

68478-13-7 Residues (petroleum), catalytic reformer fractionator residue distn. A complex residuum from the distillation of cata lytic reformer fractionator residue. It boils approximately above 399°C (750°F).June 17, 2004 Page 43 of 44 Heavy Fuel Oils Consortium Registration # 1100997

APPENDIX B.

Links to Additional Resources

Refining Processes: General Descriptions http://www.chevron.com/about/learning_center/refinery http://www.lubrizol.com/lubetheory/default.htm http://www.orionrefining.com/flow.htm http://www.osha-slc.gov/dts/osta/otm/otm_toc.html http://www.shellglobalsolutions.com/base_oils/library/library.htm http://www.shell-lubricants.com/le arningcenter/aboutoil.html http://www.shellus.com/welcome/history/hist_oil_main.html http://www.epa.gov/compliance/resources/publications/assistance/sectors/notebooks/petrefsnpt1.pdf http://www.mts.net/~dbrad1/base_oil.htm

Petroleum Related Glossaries

http://www.caltex.com.au/products_glo.asp http://www.citgo.com/CommunityInvolvement/Classroom/Glossary.jsp http://www.epplp.com/gloss.html http://www.prod.exxon.com/exxon_pr oductdata/lube_encyclopedia/ http://www.hellenic-petroleum.gr/english/glossary/gl_main.htm http://www.prod.exxon.com/exxon_pr oductdata/lube_encyclopedia/ http://www.oilanalysis.com/dictionary http://www.orionrefining.com/glossary.htm http://www.gedolbear.com/glossary.htm http://www.shellglobalsolutions.com/base_oils/glossary/a_g.htm http://www.ursa-texaco.com/English/glossary_a.html http://www.eia.doe.gov/pub/oil_gas/petro leum/data_publications/petroleum_marketing_annual/current/pdf/gloss ary.pdfJune 17, 2004 Page 44 of 44 Heavy Fuel Oils Consortium Registration # 1100997

APPENDIX C.

Robust Summary

(Separate document)