UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, DC 20460

			OFFICE OF  PREVENTION, PESTICIDES,  AND TOXIC SUBSTANCES

 								

	Memorandum								Feb.14, 2008

Subject:	 Product Chemistry Science Chapter for Creosote (P1/P13 and P2
Fractions) Reregistration Eligibility Decision (RED) Process

From:		A. Najm Shamim, PhD, Chemist

		Regulatory Management Branch II

		Antimicrobials Division (7510P)

To:		Tim McMahon, PhD, Senior Toxicologist, and Risk Assessor

		For Creosote RED

		Antimicrobials Division (7510P)

			And

		Jackie McFarlane, CRM for Creosote RED

		Regulatory Management Branch I

		Antimicrobials Division (7510P)

Thru:		Mark Hartman, Chief

		Regulatory Management Branch II

		Antimicrobials Division (7510P)

		

DP Barcode:	

		

Product Chemistry Science Chapter on

Creosote

Introduction:

	The product chemistry science chapter for Creosote is unique and
different from other Pesticides that Agency presents here. Since very
little product  physical/chemical data on creosote ( PI/P13 and P2
fractions of coal tar creosote), Agency has used the data submitted by
the registrants and has used the open literature data available.

Heavy Duty Wood Preservative Creosote is a heterogeneous mixture of
polycyclic aromatic hydrocarbons and other heteronuclear aromatic
substances. US EPA ‘s document Guidance for the Reregistration of
Pesticide Products Containing CoalTar/Creosote 

( Document 540-RS-88-066)1 recognizes  that  “hundreds of individual
chemicals have been  identified in coal tar/creosote and Lorenz &
Gjovik2 and McNeil3 have identified eight classes of compounds commonly
found in creosote and coal tar products.” These  are listed as
follows:

1.	Non-substituted six-membered rings

2.	Heterocyclic nitrogen bases

3.	Heterocyclic oxygen and sulfur compounds

4.	Alkyl substituted compounds( including polycyclic rings)

5.	Hydroxy compounds

6.	Aromatic amines

7.	Paraffins

8.	Naphthenes

Creosote as a pesticide used for wood preservation has no manufacturing
source.  This Science Chapter deals with the Creosote mixture solution
derived from tar which is produced from carbonization of bituminous
coal. This is a coal tar fractional distillation process and from this 
two fractions namely P1/P13 and P2 are obtained. In general fractions
are collected when the temperatures are between 210 o C and 355 o C.4

Creosote Council, which represents the Creosote Industry,  submitted
the product chemistry data for the P2 and P1/P13 creosote fractions in
1992 and resubmitted the data again in 1999  in compliance to the
EPA’s Reregistration Standard and Data-Call-In issued for pesticide
products containing coal tar creosote. In the absence of EPA methodology
to determine the physical/chemical characteristics of mixtures like
creosote fractions, the Industry has supplied the data based on the
analysis performed by using the methods described by the American Wood
Preservers Association (AWPA) Standard Method for Analysis of Creosote
and Oil-Type Preservatives, specifically to analyze the creosote P2 and
P1/P13 fractions for determination of xylene insolubles, determination
of specific gravity, distillation fractions and determination of water
content in the respective fractions. 

AWPA has stated that the P1/P13  and P2 (creosote)fractions for use as
heavy duty wood preservatives ‘shall be  a pure coal tar product,
derived entirely from tar produced by carbonization of bituminous coal. 
Carbonization of coal is accomplished by distlling coal and coal tar
fraction is collected. The coal tar fraction itself consists of: light
oil, middle oil and heavy (oil) anthracene. It is the middle oil
fraction that is further distilled and various fractions from this
distillation are collected  between the temperatures of 210 o and 355 o
C. 

Open literature search shows ( James Mueller et. al )5 soil contaminated
with coal tar creosote consists of: 85% polycyclic aromatic hydrocarbons
(PAHs), 10% phenolic compounds and 5% N-, S-, and O- heterocyclics.
Table 1 lists some Polycyclic aromatic  hydrocarbons found in the P2 and
P1/P13 fractions of creosote and have been reported by the Creosote
Council in its product chemistry data submissions. Table 2 lists the 
phenolic compounds and Table 3 lists the heterocyclic compounds 5 .
These components of Tables 1,2 and 3  represent 95% of the total
constituents in coal tar creosote. It must be pointed out that among the
PAHs listed in Table 1, sixteen are on the EPA’s List of Priority
Pollutants.

Table 1

Polycyclic Aromatic Hydrocarbons ( PAHs) in Coal Tar Creosote

Compound	

Relative Percentage	

Molecular Weight                       



Naphthalene	

13	

128.2



2-Methylnaphthalene	

13	

142.2



Phenanthrene	

13	

178.2



Anthracene	

13	

178.2



1-Methylnaphthalene	

8	

142.2



Biphenyl	

8	

154.2



Fluorene	

8	

166.2



2,3-Dimethyl naphthalene	

4	

156.2



2,6-Dimethyl naphthalene	

4	

156.2



Acenaphthene	

4	

154.2



Fluoranthene	

4	

202.3



Chrysene	

2	

228.2



Pyrene	

2	

202.3



Antraquinone	

1	

208.2



2-Methyl anthracene	

1	

192.3



2,3-Benzo[b]fluorene	

1	

216.3



Benzo[a]pyrene	

1	

252.3



Table 2

Phenolic Constituents in Coal Tar Creosote

Compound	

Relative Percentage	

Molecular Wt.                                        



Phenol	

20	

94.1



o-Cresol	

10	

108.1



m-Cresol	

10	

108.1



p-Cresol	

10	

108.1



Pentachlorophenol	

10	

266.4



2,5-Xylenol	

7.5	

122.2



3,5-Xylenol	

7.5	

122.2



2,3-Xylenol	

5	

122.2



2,4-Xylenol	

5	

122.2



2,6-Xylenol	

5	

122.2



3,4-Xylenol	

5	

122.2



2,3,5-Trimethylphenol	

5	

136.0



Table 3

Heterocyclics in Coal Tar Creosote

Compound	

Relative Percentage	

Molecular Wt.                      



Heterocyclics & N-Containing Aromatics:	

	





Quinoline	

10	

129.2



Isoquinoline	

10	

129.2



Carbazole	

10	

167.2



2,4-Dimethylpyridine	

10	

107.2



Acridine	

5	

179.2



Aniline	

5	

93.1



2-Methyl quinoline	

5	

143.2



4-Methyl quinoline	

5	

143.2



Pyrrole	

5	

67.1



Pyrrolidine	

5	

71.2



S-Heterocyclics:	

	





Benzo[b]thiophene	

10	

134.2



Dibenzothiophene	

10	

184.3



O-Heterocyclics:	

	





Dibenzofuran	

10	

168.2



	

	





Table 4

Analytical Results of Creosote P2 and P1/P13 Fractions

Molecular ion (M+)	

Compound	

CAS #	

P2 fraction% (mean)	

P1/P13 fraction % (mean)



117	

Indole	

120-72-9	

0.20                 	





	

Indene	

	

0.5	

NC



128	

Naphthalene	

91-20-3	

17.3	

6.2



129	

Quinoline	

91-22-5	

0.50	

1.0



134	

Benzo[c]thiophene 	

	

0.40	

NC



142	

1-Methylnaphthalene	

90-12-0	

1.3	

2.5



142	

2-Methylnaphthalene	

91-57-6	

2.80	

5.6



154	

Biphenyl	

92-52-4	

0.71	

1.6



154	

Acenaphthene	

83-32-9	

4.40	

7.7



156	

Naphthalene	

91-20-3	

17.3	

6.2



156	

1,3-Dimethyl naphthalene	

575-41-7	

0.60	

0.80



166	

Fluorene	

86-73-7	

4.03	

6.0



167	

9H-Carbazole	

86-74-8	

1.4	

1.7



168	

3-Methyl biphenyl ( 3-phenyl toluene)	

643-93-6	

0.61	

0.30



168	

Dibenzofuran	

132-64-9	

2.3	

4.3



	

1-Ethylnaphthalene	

	

0.50	

0.60



178	

Phenenthrene	

85-01-8	

9.60	

12.8



178	

Anthracene	

120-12-7	

2.90	

3.1



179	

Benzoquinoline-1(7,8-benzoquinoline)	

230-27-3	

0.70	





180	

9H-Fluorene	

	

3.5	

6.0



182	

4-Methyldibenzofuran	

	

0.40	

0.80



184	

Dibenzothiophene	

132-65-0	

0.94	

1.3



190	

4H-Cyclopenta[def]phenanthrene	

203-64-5	

1.74	

1.5



	

Pyrene	

	

4.0	

4.7



192	

2-Methylphenanthrenes	

	

0.60	





	

Chrysene	

	

0.10	

1.4



202	

Fluoranthene	

206-44-0	

4.60	

5.5



202	

Pyrene(benzo[def]phenanthrene	

129-00-00	

3.64	





204	

2-Phenylnaphthalene	

-	

0.47	

0.20



	

Benz[e]pyrene	

	

0.50	

0.3



	

Benzo[ghi]perylene	

	

0.10	

<0.1



216	

1,2-Benzofluorene(benzo[a]fluorene	

-	

0.73	





216	

2,3-Benzofluorene	

243-17-4	

0.80	

0.90



	

Methylpyrene	

	

0.30	

0.20



228	

Benz[a]anthracene	

56-55-3	

0.20	

0.40



228	

Chrysene(benz[a]phenanthrene)	

218-01-9	

1.4	





252	

Benz[b]fluoranthene	

205-99-2	

0.51	

0.80



	

Benzo[a]pyrene	

	

	

0.40



Notes:

1.	As most of the creosote constituents are polyaromatic hydrocarbons
(PAHs) and  solubilities in water or non-aqueous media is not high,
exact and accurate quantitation is not possible. The registrants
conducted a quantitation method for the PAHs based on the calibration
curves generated on four PAHs: naphthalene, ( two ring compound),
phenanthrene ( 3 ring compound) and two four ring compounds: pyrene and
chrysene. Calibaration curves were generated for these substances over a
concentration range of 2 to 1000μg/ml. These substances work as markers
for lesser known and identified PAHs in the creosote fractions. First GC
was used to separate the components and then quadruple Mass Spectrometry
was to obtain the mass spectra of individual substances. The registrants
reported the presence of components to levels less than 0.10%. The Table
4 identifies the components that are over 0.10 % in both the P2 and
P1/P13 fractions. The list also includes the presence of non-PAH
components 

Product Chemistry Assessment

The physical and chemical properties of both distillate fractions
creosote  P1/P13 and P2 are described in the following 

P1/P13 Fraction

Chemical Name:	          Coal Tar Creosote

Molecular Wt.:		No Applicable

Color:				2.5Y2/2 to 2.5Y4/2 (   Based on Munsell color scheme)

Odor:				Sharp, aromatic, wood-like

μg/ml 

Vapor Pressure:		11.1 mm Hg at 24.4 oC

Log P:				3.247

Stability:			Short term( accelerated )stability was performed on four
constituents of the mixture: naphthalene, phenanthrene pyrene and
chrysene for a period of 30 days at 60 o C. At the end of thirty day
period, naphthalene remaining was : 96.5%, phenanthrene: 87.2%, pyrene:
86.9% and chrysene: 92.4%

Viscosity;		14.60 mm/s

Storage Stability:	Not determined.

Notes:		1.	The P1/P13  samples,  provided by the Industry to Research
Triangle Institute, were distilled, within 95% confidence limit,
residues remaining were less than 1.1% as required by the AWPA Standard
A1-91 ( This test is similar to the EPA’s Certified Limit Test
required for other pesticides).

2.	Insoluble mass in Xylenes:	Duplicate determinations showed that this
fraction contained between 0.21 to 0.23% insoluble materials.

3.	Specific gravity of the fraction, for the industry sample ( single
determination) is 1.0934 ( corrected to 38oC)

4.	Moisture ( water) content for the industry sample ( single
determination) is 0.4%. 

All these results were obtained by using the AWPA Method A1-91 Series.

P2 Fraction

Chemical Name:	Coal Tar Creosote

Color:			10YR2/1 to 2.5Y5/5 ( Munsell color scheme)

Odor:			 Strong aromatic, Petroleum-like

Solubility:		306 μg/ml

Vapor Pressure:	8.6 mm Hg at 24.4 to 24.5 oC

Log P			3.311 

Stability:		

Viscosity:		15.5 mm/s at 25 oC 

The chemical structure of sixteen PAHs ( EPA Priority Pollutants ) are
provided below in the order of increasing complexity.

 

 



 

 

Some of the physical properties of selected PAHs are listed in Table 6
( Illustrated Handbook of Physical-Chemical Properties and Environmental
Fate for Organic Chemicals by D. Mackay et al., Lewis Publishers, 1992).
Many of these are measured and a number of them ( particularly the KOW)
are estimated values.

Table 6

SELECTED PHYSICO-CHEMICAL PROPERTIES OF PAHs AT 25OC



Compound	

v.p (s), mm Hg	

Log KOC	

Solubility mg/L	

Log KOW	

Henry Law constant Pa m3/mol



Indan	

15.1	

-	

0.10	

3.33	

232.82



Naphthalene	

7.8 x 10-2	

3.29	

3.1x10-2	

3.37	

43.01



1-Methyl Naphthalene	

6.6 x 10-2	

2.96	

2.8x10-2	

3.87	

44.90



2-Methyl Naphthalene	

6.7 x10-2	

3.93	

2.5x10-2	

3.86	

51.19



Biphenyl	

9.97 x 10-3	

3.57-3.77	

7x10-3	

3.90	

28.64



Bibenzyl	

3.0 x 10-3	

-	

4.3x10-3	

4.70	

16.93



Acenaphthene	

2.2 x 10-3	

3.79	

3.8x10-3	

3.92	

12.17



Acenaphthylene	

6.7 x10-3	

3.75, 3.83	

1.6x10-2	

4.00	

8.40



Fluorene	

6.7 x 10-4	

3.76	

1.9x10-3	

4.18	

7.87



Phenanthrene	

1.5 x10-4	

4.42	

1.1x10-3	

4.57	

3.24



Anthracene	

7.5 x10-6	

4.42	

4.5x10-5	

4.54	

3.96



Pyrene	

4.5 x 10-6	

4.92	

1.3x10-4	

5.18	

0.92



Fluoranthene	

9.0 x 10-6	

4.74	

2.6x10-4	

5.22	

1.037



Benzo[a]fluorene	

-	

-	

4.5x10-5	

5.40	





Benzo[b]fluorene	

-	

-	

2.0x10-6	

5.75	





Chrysene	

4.2 x 10-9	

4.89	

-	

1.649	

5.86



Benz[a]anthracene	

2.0 x 10-5	

4.57	

1.1x10-5	

5.91	

0.581



Benzo[a] pyrene	

5.2 x 10-9	

5.48	

3.8x10-6	

6.04	

0.046



Benzo[e] pyrene	

5.5 x 10-9	

4.00	

4.0x10-6	

	

0.020



Perylene	

1.0 x 10-9	

-	

4.0x10-7	

6.25	

0.003



Benzo[b]fluoranthene	

-	

5.74	

1.5x10-6	

5.80	

-



Benzo[k]fluoranthene	

3.9 x 10-9	

5.92	

8.0x10-7	

6.00	

0.016



Benzo[ghi]perylene	

	

6.20	

2.6x10-7	

6.50	

0.075



Dibenz[ah]anthracene	

2.7 x 10-12	

6.52	

6.0x10-7	

6.75	

-





Product Chemistry Chapter References

MRID			CITATION

None			American Wood Preservers’ Association Standards, 1998, pp 3-4.

None			MacKay D. et al., 1992. Illustrated Handbook of Physical-Chemical
Properties and Environmental Fate for Organic Chemicals, Lewis
Publishers.

None			Mueller J.G. et al., 1989. Environ. Sci. Technol., Volume 23(10):
1197-1201.

None			USEPA Document 540-RS-88-066. Guidance for the Registration of
Pesticide Products containing Coal Tar/Creosote.

None			Cited  in reference 4 above.

None			Cited in reference 4 above.

44141101		Wade, Terry L. 1992. Product Chemistry Methods Development and
Validation for Creosote. Analysis and Certification of Product
Ingredients: Aristech Creosote P1/P13. Pesticide Assessment Guidelines
Reference Series 62. U.S.E.P.A. Pesticide Assessment Guidelines
Subdivision D: Product Chemistry. Unpublished study prepared by
Geochemical and Environmental Research Group, Texas A&M University, for
Aristech Chemical Corporation and John H. Butala, Technical Advisor,
Creosote Council II. July 23, 1992.

44141102		Wade, Terry L. 1992. Product Chemistry Methods Development and
Validation for Creosote. American Wood Preservers Association (AWPA)
Standard Physical Characteristics: Aristech Creosote P1/P13. AWPA
Standard Methods for Analyses of Creosote and Oil-Type Preservatives
(A1-89). U.S.E.P.A. Pesticide Assessment Guidelines Subdivision D:
Product Chemistry. Unpublished study prepared by Geochemical and
Environmental Research Group, Texas A&M University, for Aristech
Chemical Corporation and John H. Butala, Technical Advisor, Creosote
Council II. August 29, 1992.

44141103		Wade, Terry L. 1992. Product Chemistry Methods Development
and Validation for Creosote. Analyses of Physical and Chemical
Characteristics: Aristech Creosote P1/P13. Pesticide Assessment
Guidelines Reference Series 63. U.S.E.P.A. Pesticide Assessment
Guidelines Subdivision D: Product Chemistry. Unpublished study prepared
by Geochemical and Environmental Research Group, Texas A&M University,
for Aristech Chemical Corporation and John H. Butala, Technical Advisor,
Creosote Council II. September 15, 1992.

44141104		Wade, Terry L. 1992. Product Chemistry Methods Development and
Validation for Creosote. Analysis and Certification of Product
Ingredients: Aristech Creosote P2. Pesticide Assessment Guidelines
Reference Series 62. U.S.E.P.A. Pesticide Assessment Guidelines
Subdivision D: Product Chemistry. Unpublished study prepared by
Geochemical and Environmental Research Group, Texas A&M University, for
Aristech Chemical Corporation and John H. Butala, Technical Advisor,
Creosote Council II. July 23, 1992.

44141105		Wade, Terry L. 1992. Product Chemistry Methods Development and
Validation for Creosote. American Wood Preservers Association (AWPA)
Standard Physical Characteristics: Aristech Creosote P2. AWPA Standard
Methods for Analyses of Creosote and Oil-Type Preservatives (A1-89).
U.S.E.P.A. Pesticide Assessment Guidelines Subdivision D: Product
Chemistry. Unpublished study prepared by Geochemical and Environmental
Research Group, Texas A&M University, for Aristech Chemical Corporation
and John H. Butala, Technical Advisor, Creosote Council II. August 29,
1992.

44141106		Wade, Terry L. 1992. Product Chemistry Methods Development and
Validation for Creosote. Analyses of Physical and Chemical
Characteristics: Aristech Creosote P2. Pesticide Assessment Guidelines
Reference Series 63. U.S.E.P.A. Pesticide Assessment Guidelines
Subdivision D: Product Chemistry. Unpublished study prepared by
Geochemical and Environmental Research Group, Texas A&M University, for
Aristech Chemical Corporation and John H. Butala, Technical Advisor,
Creosote Council II. September 15, 1992.

45355601		Sparacino, Charles M. 2000. Product Chemistry for North
American CTM Creosote P1/P13 Storage Stability and Corrosion
Characteristics. Unpublished study prepared by Research Triangle
Institute. March 31, 2000.

45355602		Sparacino, Charles M. 2000. Product Chemistry for North
American CTM Creosote P2 Storage Stability and Corrosion
Characteristics. Unpublished study prepared by Research Triangle
Institute. March 31, 2000.

45355701		Sparacino, Charles M. 2000. Product Chemistry for Western Tar
Products Corp. Creosote P1 Storage Stability and Corrosion
Characteristics. Unpublished study prepared by Research Triangle
Institute. March 31, 2000.

45355702		Sparacino, Charles M. 2000. Product Chemistry for Western Tar
Products Corp. Creosote P2 Storage Stability and Corrosion
Characteristics.  Unpublished study prepared by Research Triangle
Institute. March 31, 2000.

45355801		Sparacino, Charles M. 2000. Product Chemistry for KMG-Bernuth,
Inc. Creosote P2 Storage Stability and Corrosion Characteristics.
Unpublished study prepared by Research Triangle Institute. March 31,
2000.

45355802		Sparacino, Charles M. 2000. Product Chemistry for KMG-Bernuth,
Inc. Creosote P1/P13 Storage Stability and Corrosion Characteristics.
Unpublished study prepared by Research Triangle Institute. March 31,
2000.

45355901		Sparacino, Charles M. 1998. Product Chemistry for Trenton
Sales, Inc. Creosote P1/P13 Storage Stability and Corrosion
Characteristics. Unpublished study prepared by Research Triangle
Institute. October 15, 1998.

45356001		Sparacino, Charles M. 2000. Product Chemistry for Coopers
Creek Chemical Corp. Creosote P2 Storage Stability and Corrosion
Characteristics. Unpublished study prepared by Research Triangle
Institute. March 31, 2000.

45356002		Sparacino, Charles M. 2000. Product Chemistry for Coopers
Creek Chemical Corp. Creosote P1/P13 Storage Stability and Corrosion
Characteristics.  Unpublished study prepared by Research Triangle
Institute. March 31, 2000.

45356101		Sparacino, Charles M. 2000. Product Chemistry for Koppers
Industries, Inc. Creosote P1/P13 Storage Stability and Corrosion
Characteristics. Unpublished study prepared by Research Triangle
Institute. March 31, 2000.

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摧㤅@ᬀ45356201		Sparacino, Charles M. 2000. Product Chemistry for
Reilly Industries, Inc. Creosote P1/P13 Storage Stability and Corrosion
Characteristics. Unpublished study prepared by Research Triangle
Institute. March 31, 2000.

45356202		Sparacino, Charles M. 2000. Product Chemistry for Reilly
Industries, Inc. Creosote P2 Storage Stability and Corrosion
Characteristics. Unpublished study prepared by Research Triangle
Institute. March 31, 2000.

45363901		Sparacino, Charles M. 2000. Product Chemistry for Allied
Signal Incorporated Creosote P1/P13 Storage Stability and Corrosion
Characteristics. Unpublished study prepared by Research Triangle
Institute. March 31, 2000.

45363902		Sparacino, Charles M. 2000. Product Chemistry for Allied
Signal Incorporated Creosote P2 Storage Stability and Corrosion
Characteristics. Unpublished study prepared by Research Triangle
Institute. March 31, 2000.

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