Brandt
RAB/ECAD
May 2, 1991
RAB PR£ RM1 PRESENTATION FOR C9 AROMATIC HYDROCARBON FRACTION
SUMMARY: There are no data on exposures to the C9 aromatic
hydrocarbon fraction. However, based on exposure modeling using
1,2,4-Trimethylbenzene (1,2,4-TMB), a major component of the C9
fraction, there may be health risks to consumers using solvent
based furniture polish /varnishes composed of 50% C9 fraction.
Workers may also be at risk during manufacturing, processing and
use of the C9 fraction. Based on TRI data for 1,2,4-TMB there may
be a risk to aquatic organisms from releases from one manufacturing
site. The major human health hazard concerns are reproductive and
developmental toxicity effects.
I. CHEMICAL/PHYSICAL CHARACTERISTICS
Structure:
CS,
R- CH. or R
X-2 X
1,2,3- TMB (Hemimellitene)
1,3,5- TMB (Mesitylene)
1,2,4- TMB (Pseudocumene)
TMB (mixed isomers)
o-Ethyltoluene
m-Ethyltoluen«
p-Ethyltoluen«
CAS Nos.
526-73-8
108-67-8
95-63-6
25551-13-7
611-14-3
620-14-4
622-96-8
vp
(mm HG at
25°C)
1.55
1.55
2.1
2.5
2.99
3.01
Typical %
by weight in
C9 fraction
8.2
7.6
41.3
9.1
17.4
8.6
Ethyltoluene (mixed isomers)25550-14-5
(D. Bushman, 1991)
The C9 aromatic fraction is obtained from the catalytic
reforming of crude petroleum. The major components of the C9
fraction ar« th« mixed ethyltoluen« (ET) (ortho-, meta- and para-
ET) and trim*thyIbenzene (1,2,3, 1,3,5- and 1,2,4-TMB) isomers
which have the same molecular weight of 120.2, boil over a narrow
range and are similar in chemical and biological properties. A
small percentage of other compounds mak« up the rest of the
fraction (Bushman, 1991, pp.1-8). ET and TMB are colorless liquids
at room temperature, readily soluble in most organic solvents and
relatively insoluble in water.
II. BACKGROUND/SELECTION RATIONAL
-------
The Tenth Report of the Interagency Testing committee (ITC)
(47 FR 22585, May 25, 1982) designated ET and 1,2,4-TMB for
priority consideration for environmental and health effects
testing. In its Eleventh Report (47 FR 54624, December 3, 1982),
the ITC recommended that the other TMB isomers (1,2,3-and l,3,rj-)
also be considered for testing. The testing recommendations were
based on the exposure potential of the chemicals and the lack of
sufficient information on environmental and health effects.
Subsequently, the Environmental Protection Agency (EPA) promulgated
a final Phase I rule on May 17, 1985 (50 FR 20662) in 40 CFR
799.2175, requiring testing of the C9 aromatic hydrocarbon fraction
(C9 fraction), which contains ET and TMB as its major components.
On January 23, 1987 a Phase II rule (52 FR 2522) was promulgated
issuing final test standards and reporting requirements. Modifica-
tions to the rule were made on June 29, 1989 (54 FR 27352).
EPA found (l) production and use of the C9 fraction was
substantial as a solvent and as a component in motor fuels; (2)
widespread exposure exists; (3) existing data are inadequate to
predict the effects of exposure; and (4) testing was required to
assess the potential of the C9 fraction to cause adverse health and
environmental effects.
Section 4 test data and evaluations of the C9 fraction were
reviewed and commented on by the Health and Environmental Review
Division (HERD) of OTS to assess the adequacy of the data for use
in risk assessment. Subchronic/chronic toxicity tests, metabolism
studies and environmental fate and effects tests were not required
because sufficient data existed (FR 20663-20664, May 17, 1985;
McCormack, 1990, p.2).
III. FINDINGS AND CONCLUSIONS
A. PRODUCTION/USB. The 1985 estimate of production volume
for C9 fraction solvents was 379 million pounds/year (Rawie, 1991,
pp. 1-2). The total C9 fraction manufactured is produced by fewer
than 200 facilities (including 190 petroleum refineries), with an
annual production of 77,729 million pounds. The primary manufac-
turing process is petroleum refining (Pederson, 1991, p.l).
The primary use of the C9 fraction, 99.448% of the production
volume, is as a gasoline additive. C9 fraction solvents are used
in coatings, cleaners, other chemicals and pesticides, printing and
inks and other miscellaneous uses (Pederson, 1991, p.2). Data
representing 80% of domestic production of C9 fraction solvents
showed a median ET/TMB content of 80%, with a range of 75 -90% (FR
20673, May 17, 1985). A wide range of solvents also exists which
are adequate substitutes for C9 solvents (Rawie, 1991, p.6).
B. ENVIRONMENTAL RELEASES. The C9 fraction is released to
the environment in substantial quantities through its use in motor
-------
fuels and solvents. only one component (1,2,4-TMB) is a Toxic
Release Inventory (TRI) chemical (Pederson, 1991, p.l).
C. ENVIRONMENTAL FATE. Most released ET and 1MB partitions
to the atmosphere.
D. EXPOSURES, (a) Occupational; Exposure to the C9 fraction
is from dermal contact with, or inhalation of, vapors.
(1) Manufacturing - There are no data on worker exposure to
the C9 fraction during manufacturing. However, using toluene in
the petroleum refinery industry as a reference, less than 600
workers would potentially be exposed to the C9 fraction in the
petroleum refinery industry. Petroleum refining is the primary
manufacturing process of the C9 fraction (Pederson, 1991, p.l).
Using OSHA monitoring data (4-84 to 4-83) on toluene exposures in
certain manufacturing and processing industries, inferences can be
made as to exposures to the C9 fraction in those same industries.
In general, worker exposures to toluene, and by inference, to the
C9 fraction, can be expected to be relatively low. [This is based
on the OSHA data on toluene indicating that from 87-100% of the air
samples taken from the following manufacturing industries:
petroleum refining, plastics materials and resins, cyclic crudes
and intermediates, and industrial organic chemicals, were less than
% the toluene Permissible Exposure Level (PEL) of 200 ppm.]
Exposures to the C9 fraction can be expected to be less than those
from toluene due to the C9 fraction's lower volatility.
(2) Processing - There are no data on worker exposure to the
C9 fraction or to TMB during processing (Pederson, 1991, pp. 2,9).
Using the same train of thinking as above, the worker exposures to
the C9 fraction during processing can be expected to be relatively
low. [This is based on the OSHA data on toluene indicating that
from 87-97% of the air samples taken from the following processing
industries — plastics materials and resins, paints and allied
products, and cyclic crudes and intermediates — were less than S
the PEL.]
(3) Use - There are no data on worker exposure to the C9
fraction during industrial use. OSHA exposure monitoring data on
TMB for workers using C9 fraction solvents are incomplete.
There are no data on household worker exposure to C9 fraction
solvents used for cleaning and polishing furniture, etc.
(b) General Population. There are no data on general
population exposure to the C9 fraction from either air or water
release. Estimates of worst case inhalation exposure modeling to
1,2,4-TMB, based on the Toxic Release Inventory (TRI) data for
populations near 10 air release sites, ranged from 1 to 14 tag/day,
with a median of 3 mg/day. The two highest levels were 14 and 6
mg/day (Lynch, 1991, p.3).
-------
Estimates of exposure to 1,2,4-TMB by ingestion of con-
taminated drinking water (DW) and contaminated fish (FI) were made
at 3 sites with the following results (Lynch, 1991, p.4):
DW (ua/yr) FI fua/yr)
12.5 46.1
12 44.25
2.03 7.49
(c) Consumer. No data on levels of consumer exposure to the
C9 fraction are available. Estimated exposures to 1,2,4-TMB have
been calculated assuming that the chemical is used as a solvent or
vehicle in consumer paints or solvent-based varnishes at a concen-
tration of 50%. Exposures via dermal contact (D) and inhalation
(I) are estimated below (Lynch, 1991, p. 5):
Consumer Product Route of Exposure
Exposure fmcr/yrl fm,g/per event)
Solvent-based Varnish D 1.06 x 104 1330
Aerosol Spray Paint D 5.60 x 102 560
Aerosol Furniture Polish I 4.01 x 104 308
Solvent-based Varnish I 7.09 x 102 89
Aerosol Spray Paint I 1.50 x 10* 15
For purposes of risk assessment, dermal absorption is calculated at
10% of exposure; inhalation is calculated at 100%.
(d) Environmental. The estimated K values of TMB are
indicative of moderate mobility in soil (US EPA, 1987, p. 3). The
concern has been in the release of TMB to landfills and possible
leaching out of the material. A rule, however, banning releases of
TMB to landfills was promulgated under RCRA, 1990 (personal
communication with Dave Lynch, April 11, 1991) .
Surface water concentrations resulting from the discharges and
annual exposure to 1,2,4-TMB are estimated below for three sites
(Lynch, 1991, p.4) :
Mean flow Low flow
fug/ 11 (ppm) fua/11
17.1 0.017 263 0.26
16.43 0.016 15.66 0.015
2.78 0.002 21.66 0.02
-------
B. HAZARDS. The toxicity of the C9 fraction is assessed here
as a complete entity rather than by its component chemicals. The C9
fraction test substance was required to have a minimum ET content
of 22%, a minimum TMB content of 15%, and minimum total ET/TMB
content of 75%. (Page 1 shows the composition of a typical C9
fraction.) The health effects of concern are as follows (HERD,
1991, p.l):
Reproductive
LOEL: 100 mg/kg/day (100 ppm/inhalation/rat)
Developmental
LOEL: 210 mg/kg/day (100 ppm/inhalation/mouse)
NOEL (Maternal Tox.): 210 mg/kg/day (100 ppm/inhal/mouse)
LOEL (Maternal Tox.): 1100 mg/kg/day (500 ppm/inhal/mouse)
Aquatic
Acute IC50 (daphnid) :
Acute EC50 (algae) :
16-day ECSO (daphnid)
1.44 mg/1 (ppm)
0.84 mg/1 (ppm)
1.08 mg/1 (ppm)
0.18 mg/1 (ppo)
(TMB)
(ET)
(both TMB and ET)
Human Health Observations - Of 27 workers who had worked for
several years with a solvent (Fleet-X-DV99) containing 30% 1,3,5-
TMB, 50% 1,2,4-TMB and other hydrocarbons (1,2,2-TMB and 1-methyl-
4-ethylbenzene) some experienced nervousness, tension, anxiety ajid
asthmatic bronchitis, as well as hematologic effects (ACGIH TLV's.
4th ED & Suppl. 1980, p. 416, IN HSDB, Pseudocumene; US EPA, 1987).
Developmental/Reproductive Toxicity. A C9 fraction inhalation
developmental toxicity study in mice established a LOEL of 100 ppm
(210 mg/kg/day) (Campbell, 1989, Conclusions). No NOEL was estab-
lished. The maternal toxicity LOEL is 500 ppm (1100 mg/kg/day); a
probable maternal toxicity NOEL is 100 ppm (210 mg/kg/day) (Camp-
bell, 1989 IN HERD, 1991, p.3).
A 3-generation C9 fraction inhalation reproductive study in
rats showed evidence of parental and developmental toxicity at all
doses (100, 500 and 1500 mg/kg/day). The LOEL is 100 mg/kg/day; no
NOEL was established (Seed, 1989 IN HERD, 1991, p.2).
Neurotoxieity. Adult male rats exposed by inhalation to C9
fraction concentrations of 0, 100, 500 or 1500 ppm (100, 500 or
1500 mg/kg/day) for 13 weeks showed a decrease in body weight by
13%, after the first week, observed in the high-dose group only.
No signs of neurotoxicity were evident, as evaluated by motor
activity, startle response, forelimb and hindlimb grip strength,
hindlimb splay and thermal responses (McCormack, 1990, p.11; Rees,
1989 IN HERD, 1991, p.4).
A variety of neur©behavioral effects were observed in the
developmental study with mice following C9 fraction inhalation of
-------
1500 ppm (3200 mg/kg/day). The LOEL for neurobehavioral effects
was established at 1500 ppm. The NOEL equaled 500 ppm (Rees, 1989
IN HERD, 1991, p.4) .
Mutagenicity. The C9 fraction does not induce gene mutations
in prokaryotes or in mammalian cells in culture. It does not cause
chromosomal aberrations in mammalian cells in vitro or in vivo or
DNA effects in mammalian cells (Cimino, 1988 IN HERD, 1991, p.5) .
These negative results of the mutagenicity studies did not trigger
any additional mutagenicity or carcinogenicity testing,, as
specified in the C9 test rule (Cimino, 1988).
There are a lack of carcinogenicity test data on the C9
fraction (US EPA, 1986 IN US EPA, 1987, p.7).
Acute, subchronic and other Toxicity.
Animal Data - No acute toxicity data are available for tha C9
fraction as a whole. The para-ET (p-ET) and 1,2,4-TMB isomers are
the best characterized constituent chemicals. Both have low acute
toxicity.
- Four out of 16 rats died of respiratory failure during a
single continuous 24-hour exposure to 2400 ppm 1,3,5-TMB (ACGIH,
TLV's 3rd Ed and Suppl 1971-1979, p.269, IN HSDB, Mesitylene).
Inhalation exposure to rats of 979 ppm p-BT, 6 hr/day 5
days/wk for 13 weeks resulted in liver enlargement. Gavage
administration of 400 or 800 mg/kg/day for 14 days also resulted in
liver enlargement (McCormack, 1990, p.4).
Rats exposed by inhalation to tha TMB (3-isomer) mixture at
1700 ppra for 10-21 days had no adverse effects in rats. Exposure
for 4 months to the same concentration caused diminished weight
gain and a progressive increase in lymphopenia and neutrophil with
a marked depression of the central nervous system (OP. cit. HSDB
Pseudocumene).
Ecotoxicity. The calculated log P values on TMB and ET are
4.1 and 4.0, respectively. Both values suggest a high potential
for accumulation of these substances in aquatic organisms.
Calculated acute aquatic toxicities include (HERD, 1991, p.6):
-------
rma/1)
96-hr LC50 (fish): 10.9 (both ET and TMB isomers)
48-hr IC50 (daphnid) : 1.44 (both ET and TMB isomers)
96-hr EC50 (algae): 0.84 (TMB)
1.08 (ET-)
16-day EC.0 (daphnid): 0.18 (both ET and TMB isomers)
Chronic algal toxic ity: 0.24 (TMB)
0.34 ppm (ET)
Calculated acute daphnid and acute algal values indicate a
moderate to high acute toxicity for both groups of isomers. Acute
testing using daphnids and algae would be necessary to confirm
these estimates of toxicity. Calculated chronic values suggest a
low chronic toxicity for both groups of isomers (HERD, 1991, p. 6).
F. RISKS.
Possible risks to consumers from use of aerosol furniture
polish.
Possible risks to workers- during manufacturing, process-
ing, and during use of C9 as an industrial solvent and as
a household end product.
Possible risks to aquatic organisms from one release site.
IV. REGULATION
The current PEL for individual isomers or mixtures of TMB is
25 ppm (125 mg/m3) , with a STEL of 35 ppm (170 mg/m3).
V. DISCUSSION
(a) Consumer. Health risks to consumers may result from the
inhalation of vapors and/or from dermal absorption of the C9
fraction solvent end products. Using a worst case exposure
scenario of consumer inhalation exposure to vapors from aerosol
furniture polish, the MOEs from the LOELs for reproductive toxicity
(100 mg/kg/da) and for developmental toxicity (210 mg/kg/da) from
animal studies would be 17 and 35, respectively. Risks to
consumers from combined dermal and inhalation exposures to
furniture varnish would also give low MOE's (22, and 48 respective-
ly) . Since the modeling is based on worst case assumptions,
including polishing furniture every 3 days, the risks would not
necessarily be to the average consumer. However, using these
assumptions there may be risks to persons who clean households as
a profession, (see occupational section).
Another possible risk to consumers may be from exposure to the
C9 fraction when pumping gasoline. This concern is addressed in
"SECTION 4 ISSUES" (Section VI., below).
-------
(b) occupational! There are no worker exposure data on the C9
fraction. However, exposure levels to toluene in similar indus-
tries (including petroleum refining) indicate that most worker
exposures during manufacturing and processing would be to concen-
trations less than k the PEL. This comparison with toluene is only
a gross one since the PEL for toluene is 200 ppm, and that for TMB,
the major component of the C9 fraction, is 25 ppm. However, since
toluene is more volatile than the C9 fraction, a gross comparison
is possible.
If C9 fraction exposures were similar to those of toluene,
i.e., most of the exposures were < ** PEL for TMB (< % of 25 ppm),
workers would be exposed below the LOELs for reproductive and
developmental toxicities from animal studies (100 mg/kg/da, and 210
mg/kg/da, respectively). However, there would still be a concern
for reproductive and developmental toxicities risk since the margin
of exposure from these LOELs would be 8 and 16, respectively. [210
mg/kg/da (Developmental LOEL) * 13 mg/kg/da; and 100 mg/kg/da
(Reproductive LOEL) + 13 mg/kg/da.] (*Sea calculations below.)
OSHA data on worker exposure to TMB during use as an industri-
al solvent is incomplete. It indicates that about 8% of samples
taken were less than the detection level. OSHA data on worker
exposures to toluene to the same Standard Industrial Codes (SICs)
for industrial use indicate that some exposures are > ^ PEL.
Therefore, there may also be a concern for reproductive and
developmental toxicity risk due to industrial solvent exposures.
There is no data on exposure to the C 9 fraction as a solvent
in end products during use by professional household cleaners.
There may be a health risk to these persons who usa these products
on a daily basis (see discussion in consumer section).
(c) General Population. There are no data on C9 friction
releases to air. However, an estimate of the C 9 fraction
exposures can be made using TRI data on 1,2,4-TMB. The TRI data
does not tell us if the C9 fraction was released from these sites,
and only 1,2,4-TMB was measured, or if only 1,2,4-TMB was released.
However, it is known that 1,2,4-TMB is used primarily as a
component of the C9 fraction. If the 1,2,4-TMB data can be used as
a measure of exposure expected from the C9 fraction, then the
margin of exposures (MOE) from the LOEL (lOOmg/kg/da) for reproduc-
tive toxicity from an animal study would be 357 and 833, respec-
tively for the two sites with greatest releases of 1,2,4-TMB.
These MOEs indicate that the expected exposures would be well below
the LOELs from the animal study. Given that the modeling of the
TRI data uses worst case assumptions, there does not appear to be
a health risk to the general population from air releases.
Exposure to contaminated drinking water and contaminated fish
present no risk, since the estimated levels are below the level of
concern.
8
-------
(d) Environmental. There is a concern for potential risk
to aquatic organisms during low flow conditions at a Lancaster PA
site. Surface water low flow concentrations based on TRI data on
1,2,4-TMB were above a chronic effect level for daphnids.
*[TMB PEL=» 25 ppm or I25mg/m3; I25mg/m3 X I,25m3/hr X 8 hr day =
1250 mg/da exposure. Divide by a 50 kg person - 25 rag/kg/da; \ the
TMB PEL - 13 mg/kg/da]
VI. SECTION 4 ISSUES
Although EPA recognized that there may be substantial human
exposure to gasoline and its component hydrocarbons, including the
C9 fraction, the Agency did not consider exposure to the C9
fraction in gasoline as part of its basis for finding substantial
human exposure to the C9 fraction (50 FR 20664, May 17, 1985).
EPA justifies its decision by indicating that the C9 fraction was
among approximately 300 chemical species in gasoline and the
concentrations in a typical motor gasoline are relatively low
(approximately 3%) . Also, since existing data showed unleaded
gasoline to be carcinogenic in laboratory animal inhalation
studies, exposure controls for gasoline were expected to be based
on these data or on additional testing of gasoline aimed at
characterizing its overall toxicity as a complex product. Data on
the C9 fraction alone would be of minimal relevance to that overall
determination (50 FR 20666, May 17, 1985).
VII. OTHER ISSUES
EPA currently has a Petroleum Cluster Policy group. An RM1
meeting is scheduled for May 1, 1991.
VIII. RECOMMENDATIONS
1. Notify CPSC of the possible risks to consumers from C9
fraction solvent end products and the need for exposure informa-
tion.
2. Bring information to the attention of OSHA, NIOSH, and
ACGIH indicating the need for exposure information to verify a
possible risk to workers from the C9 fraction.
3. Give information to appropriate EPA Regions to communicate
to the industrial site a possible aquatic toxicity concern.
4. Send copy of RM1 information to Petroleum Cluster Policy
Group.
-------
IX. REFERENCES
Bushman, Daniel R. January, 1991. RMl Industrial Chemicals Branch
(ICB) Form.
Cimino, M. April 1, 1988. Review of Mutagenicity Testing Results
on C9 Aromatic Hydrocarbon Fraction. Memorandum from P.
Fenner-Crisp, Health and Environmental Review Division (HERD)
to R. Troast, Test Rules Development Branch, Existing Chemical
Assessment Division (ECAD). Washington, DC: OTS, US EPA.
HERD. February 1991. HERD (Health and Environmental Review
Division) Profile Working Draft, C9 Aromatic Hydrocarbons.
HSDS. Mesitylene. Hazardous Substance Databank.
-Pseudocumene.
Lynch, David G. April 2, 1991. Preliminary Exposure Assessment for
C-9 Hydrocarbons. Memorandum from David G. Lynch, Exposure
Assessment Branch (EAB) , to Ethe], Brandt, Existing Chemical
Assessment Division (ECAD).
McCormack, K., P. Wirdzek, R. Troast, R. Nelson, N. Chandhari and
Merrifield. 9/6/90. Summary of C9 Aromatic Hydrocarbon
Fraction: Ethyltoluenes, and Trimethylbenzenes.
Pederson, Mark E. March 7, 1991. RMl Initial Chemical Engineering
Branch (CEB) Summary, Aromatic C9 Hydrocarbons.
Rawie, Carol. Feb. 20, 1991. RMl Economic Analysis for C-9
Hydrocarbons. Memorandum from Carol Rawie, Regulatory Impacts
Branch (RIB), Economics and Technology Division (ETD), to
Ethel Brandt, Existing Chemical Assessment Division (ECAD):
Rees, D. Cooper. 1989. Section 4 Testing of C9 Aromatic Hydrocar-
bons: Neurotoxicity data. Memorandum from C. Rees, Toxic
Effects Branch (TEB), to C. Auer, Health and Environmental
Review Division (HERD). Washington, DC: OTS: USEPA.
U.S. Environmental Protection Agency. June, 1987. Office of
Research and Development (ORD), Office of Health and
Environmental Assessment (OHEA), Environmental Criteria and
Assessment Office (ECAO), "Health Effects Assessment for
Trimethylbenzenes11.
10
-------
RM1 Meeting Summary
Final 8/28/91/CG
Date: May 22, 1991
Subject: C-9 Aromatics
Chairman: Jim Willis
Coordinator: Ethel Brandt
Supporting Documents: Briefing paper
Background Information:
The C9 aromatic hydrocarbon fraction is obtained from the
catalytic reforming of crude petroleum. The Interagency. Testing
Committee recommended that C9 fraction be tested under Section 4 of
TSCA, based on the exposure potential and the lack of sufficient
information on environmental and health effects.
77,729 million pounds/yr of C9 fraction are produced. The
primary use of this volume is as a gasoline additive. Other uses
include use as a solvent in coatings, cleaners, other chemical and
pesticides, printing and inks and other miscellaneous uses. A wide
range of substitutes exists for C9 solvents.
Releases of C9 fraction to the environment occur to the
atmosphere (via stack and fugitive emissions, and evaporation from
spills), to water, and to soil (via landfill waste).
There are no data on worker exposure to C9 fractions during
manufacture, processing, or use, nor is there any data available on
household worker exposure, general population exposure, or consumer
exposure to C9 fractions. Worker exposures can be estimated using
toluene as a reference. The estimated exposures during manufacture
and processing are low.
Surface water concentrations resulting from the discharges and
annual exposure to 1,2,4-Trimethylbenzene have been estimated, and
are listed in the briefing paper.
The toxicity of the C9 fraction as a complete entity was
assessed by HERD, and the concerns are listed in the briefing
paper, along with LOELs and NOELs. In general, concerns were for
reproductive and developmental toxicity, as well as a moderate to
high acute toxicity to aquatic organisms, and low chronic toxicity
to aquatic organisms.
There is a possible risk to consumers from the use of aerosol
furniture polish. Workers could be at risk during manufacturing,
processing and use of C9 as an industrial solvent and as a
household product. Risks to aquatic organisms are possible from
one release site.
-------
Page 2
C-9 Aromatics
8/28/91
Discussion:
There has been no verification that C-9 fraction is actually
found in any consumer products. It was therefore decided that such
verification should be the first order of business. However, it
does not seem, prudent to spend a great deal of resources on such
verification. ETD will perform a limited survey of manufacturers.
If no information can be easily obtained, the search will be
discontinued. If it can be verified that the C-9 fraction is in
consumer products, then a letter of concern will be written to
producers, as well as to CPSC, based on the ethylhexanoic acid
model. This letter will notify producers and CPSC of the possible
risk to consumers from C9 fraction solvent end products and the
need for exposure information.
The information will also be given to the appropriate EPA
Region for communication of a possible concern for aquatic toxicity
for the industrial site.
The RM1 information packet will be sent to the Petroleum
Cluster Policy Group, as well as the Indoor Air Cluster Group.
With the exception of the above mentioned activities and
referrals, C9 Aromatic Hydrocarbons will be dropped from further
RM1 review.
------- |