[Federal Register Volume 67, Number 200 (Wednesday, October 16, 2002)]
[Notices]
[Pages 63913-63916]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-26308]


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ENVIRONMENTAL PROTECTION AGENCY

[OPPT-2002-0056; FRL-7275-8]


1,1,2-Trichloroethane Tier I Program Review Testing; Notice of 
Availability and Solicitation of Comment

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice.

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SUMMARY: Under section 4 of the Toxic Substances Control Act (TSCA), 
EPA issued a testing consent order that incorporated an enforceable 
consent agreement (ECA) relating to 1,1,2-trichloroethane (TCE). The 
companies subject to this ECA agreed to conduct toxicity testing, 
develop a computational dosimetry model for route-to-route 
extrapolations, and develop pharmacokinetics and mechanistic testing 
data that are intended to satisfy the toxicological data needs for TCE 
identified in a TSCA section 4 proposed test rule for a number of 
hazardous air pollutant chemicals. This notice announces that EPA is 
starting the Program Review component of the TCE ECA alternative 
testing program, and solicits comment on data received under the Tier I 
Program Review testing segment of the TCE ECA. Comments are expected to 
inform EPA's decision on whether or not additional data and/or model 
development are needed before Tier II testing and computational 
dosimetry modeling for route-to-route extrapolations proceed for the 
Tier II endpoints listed in the TCE ECA.

DATES: Comments, identified by docket ID number OPPT-2002-0056, must be 
received on or before November 15, 2002.

ADDRESSES: Comments may be submitted electronically, by mail, or 
through hand delivery/courier. Follow the detailed instructions as 
provided in Unit I. of the SUPPLEMENTARY INFORMATION.

FOR FURTHER INFORMATION CONTACT: For general information contact: 
Barbara Cunningham, Acting Director, Environmental Assistance Division 
(7408M), Office of Pollution Prevention and Toxics, Environmental 
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-
0001; telephone number: (202) 554-1404; e-mail address: [email protected].
    For technical information about EPA's Program Review contact: 
Richard Leukroth or John Schaeffer, Chemical Control Division (7405M), 
Office of Pollution Prevention and Toxics, Environmental Protection 
Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460-0001; 
telephone number: (202) 564-8157; e-mail address: [email protected].

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

    This action is directed to the public in general, and may be of 
particular interest to those persons who are or may be required to 
conduct testing of chemical substances under TSCA. Since other entities 
may also be interested, the Agency has not attempted to describe all 
the specific entities that may be affected by this action. If you have 
any questions regarding the applicability of this action to a 
particular entity, consult the technical person listed under FOR 
FURTHER INFORMATION CONTACT.

B. How Can I Get Copies of this Document or Other Related Documents?

    1. Docket. EPA has established an official public docket for this 
action under docket identification (ID) number OPPT-2002-0056. OPPT-
2002-0056 is the continuation docket for the TCE ECA which originated 
under OPPTS Docket Number 42198. The official public docket consists of 
the documents specifically referenced in this action, any public 
comments received, and other information related to this action. 
Although a part of the official docket, the public docket does not 
include Confidential Business Information (CBI) or other information 
whose disclosure is restricted by statute. The official public docket 
is the collection of materials that is available for public viewing at 
the EPA Docket Center, Rm. B102-Reading Room, EPA West, 1301 
Constitution Avenue, NW., Washington, DC. The EPA Docket Center is open 
from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal 
holidays. The EPA Docket Center Reading Room telephone number is (202) 
566-1744 and the telephone number for the OPPT Docket, which is located 
in the EPA Docket Center, is (202) 566-0280.
    2. Electronic access. You may access this Federal Register document 
electronically through the EPA Internet under the ``Federal Register'' 
listings at http://www.epa.gov/fedrgstr/.
    An electronic version of the public docket is available through 
EPA's electronic public docket and comment system, EPA Dockets. You may 
use EPA Dockets at http://www.epa.gov/edocket/ to submit or view public 
comments, access the index listing of the contents of the official 
public docket, and to access those documents in the public docket that 
are available electronically. Although not all docket materials may be 
available electronically, you may still access any of the publicly 
available docket materials through the docket facility identified in 
Unit I.B.1. Once in the system, select ``search,'' then key in the 
appropriate docket ID number.
    Certain types of information will not be placed in the EPA Dockets. 
Information claimed as CBI and other information whose disclosure is 
restricted by statute, which is not included in the official public 
docket, will not be available for public viewing in EPA's electronic 
public docket. EPA's policy is that copyrighted material will not be 
placed in EPA's electronic public docket but will be available only in 
printed, paper form in the official public docket. To the extent 
feasible, publicly available docket materials will be made available in 
EPA's electronic public docket. When a document is selected from the 
index list in EPA Dockets, the system will identify whether the 
document is available for viewing in EPA's electronic public docket. 
Although not all docket materials may be available electronically, you 
may still access any of the publicly available docket materials through 
the docket facility identified in Unit I.B.1. EPA intends to work 
towards providing electronic access to all of the publicly available 
docket materials through EPA's electronic public docket.

[[Page 63914]]

    For public commenters, it is important to note that EPA's policy is 
that public comments, whether submitted electronically or in paper, 
will be made available for public viewing in EPA's electronic public 
docket as EPA receives them and without change, unless the comment 
contains copyrighted material, CBI, or other information for which 
disclosure is restricted by statute. When EPA identifies a comment 
containing copyrighted material, EPA will provide a reference to that 
material in the version of the comment that is placed in EPA's 
electronic public docket. The entire printed comment, including the 
copyrighted material, will be available in the public docket.
    Public comments submitted on computer disks that are mailed or 
delivered to the docket will be transferred to EPA's electronic public 
docket. Public comments that are mailed or delivered to the docket will 
be scanned and placed in EPA's electronic public docket. Where 
practical, physical objects will be photographed, and the photograph 
will be placed in EPA's electronic public docket along with a brief 
description written by the docket staff.

C. How and To Whom Do I Submit Comments?

    You may submit comments electronically, by mail, or through hand 
delivery/courier. To ensure proper receipt by EPA, identify the 
appropriate docket ID number in the subject line on the first page of 
your comment. Please ensure that your comments are submitted within the 
specified comment period. Comments received after the close of the 
comment period will be marked ``late.'' EPA is not required to consider 
these late comments. If you wish to submit CBI or information that is 
otherwise protected by statute, please follow the instructions in Unit 
I.D. Do not use EPA Dockets or e-mail to submit CBI or information 
protected by statute.
    1. Electronically. If you submit an electronic comment as 
prescribed in this unit, EPA recommends that you include your name, 
mailing address, and an e-mail address or other contact information in 
the body of your comment. Also include this contact information on the 
outside of any disk or CD ROM you submit, and in any cover letter 
accompanying the disk or CD ROM. This ensures that you can be 
identified as the submitter of the comment and allows EPA to contact 
you in case EPA cannot read your comment due to technical difficulties 
or needs further information on the substance of your comment. EPA's 
policy is that EPA will not edit your comment, and any identifying or 
contact information provided in the body of a comment will be included 
as part of the comment that is placed in the official public docket, 
and made available in EPA's electronic public docket. If EPA cannot 
read your comment due to technical difficulties and cannot contact you 
for clarification, EPA may not be able to consider your comment.
    i. EPA Dockets. Your use of EPA's electronic public docket to 
submit comments to EPA electronically is EPA's preferred method for 
receiving comments. Go directly to EPA Dockets at http://www.epa.gov/edocket, and follow the online instructions for submitting comments. 
Once in the system, select ``search,'' and then key in docket ID number 
OPPT-2002-0056. The system is an ``anonymous access'' system, which 
means EPA will not know your identity, e-mail address, or other contact 
information unless you provide it in the body of your comment.
    ii. E-mail. Comments may be sent by e-mail to [email protected], 
Attention: Docket ID Number OPPT-2002-0056. In contrast to EPA's 
electronic public docket, EPA's e-mail system is not an ``anonymous 
access'' system. If you send an e-mail comment directly to the docket 
without going through EPA's electronic public docket, EPA's e-mail 
system automatically captures your e-mail address. E-mail addresses 
that are automatically captured by EPA's e-mail system are included as 
part of the comment that is placed in the official public docket, and 
made available in EPA's electronic public docket.
    iii. Disk or CD ROM. You may submit comments on a disk or CD ROM 
that you mail to the mailing address identified in Unit I.C.2. The disk 
or CD must be labeled: Attention: Docket ID Number OPPT-2002-0056. 
These electronic submissions will be accepted in WordPerfect or ASCII 
file format. Avoid the use of special characters and any form of 
encryption.
    2. By mail. Send your comments to: Document Control Office (7407M), 
Office of Pollution Prevention and Toxics (OPPT), Attention: Docket ID 
Number OPPT-2002-0056, Environmental Protection Agency, 1200 
Pennsylvania Ave., NW., Washington, DC 20460-0001.
    3. By hand delivery or courier. Deliver your comments to: OPPT 
Document Control Office (DCO) in EPA East Building Rm. 6428, 1201 
Constitution Ave., NW., Washington, DC. Attention: Docket ID Number 
OPPT-2002-0056. The DCO is open from 8 a.m. to 4 p.m., Monday through 
Friday, excluding legal holidays. The telephone number for the DCO is 
(202) 564-8930.

D. How Should I Submit CBI to the Agency?

    Do not submit information that you consider to be CBI 
electronically through EPA's electronic public docket or by e-mail. You 
may claim information that you submit to EPA as CBI by marking any part 
or all of that information as CBI (if you submit CBI on disk or CD ROM, 
mark the outside of the disk or CD ROM as CBI and then identify 
electronically within the disk or CD ROM the specific information that 
is CBI). Information so marked will not be disclosed except in 
accordance with procedures set forth in 40 CFR part 2.
    In addition to one complete version of the comment that includes 
any information claimed as CBI, a copy of the comment that does not 
contain the information claimed as CBI must be submitted for inclusion 
in the public docket and EPA's electronic public docket. If you submit 
the copy that does not contain CBI on disk or CD ROM, mark the outside 
of the disk or CD ROM clearly that it does not contain CBI. Information 
not marked as CBI will be included in the public docket and EPA's 
electronic public docket without prior notice. If you have any 
questions about CBI or the procedures for claiming CBI, please consult 
the person listed under FOR FURTHER INFORMATION CONTACT.

E. What Should I Consider as I Prepare My Comments for EPA?

    EPA invites interested parties to provide views on the Companies' 
Tier I Program Review testing reports titled: ``Pharmacokinetics of 
1,1,2-Trichloroethane in Rats and Mice'' and ``Physiologically Based 
Pharmacokinetic Model Development, Simulations, and Sensitivity 
Analysis for Repeated Exposure to 1,1,2-Trichloroethane.'' These 
reports describe a dosimetry model for route-to-route extrapolation and 
development of pharmacokinetics and mechanistic testing data (PK/MECH 
data) that will support the use of this model for quantitative route-
to-route extrapolations specific to endpoints listed under Tier II of 
the TCE ECA. The model and PK/MECH data described in these reports, if 
deemed acceptable to EPA, will be applied to support the TCE ECA Tier 
II testing and computational dosimetry model extrapolation reporting 
called for under Tier II of the TCE ECA. EPA is interested in comments 
on the PK/MECH data, the TCE computational dosimetry model for route-
to-route extrapolation, and the utility of resulting derived 
computational data from the TCE dosimetry model that will

[[Page 63915]]

be developed under Tier II of the TCE ECA. Additionally, EPA is 
interested in receipt of any data or information for the Agency to 
consider during development of EPA's Program Review of the TCE ECA 
alternative testing program with regard to approaches not considered as 
well as potential impacts of the various options (including possible 
unintended consequences). You may find the following suggestions 
helpful in preparing your comments:
    1. Explain your views as clearly as possible.
    2. Describe any assumptions that you used.
    3. Provide copies of any technical information and/or data you used 
that support your views.
    4. If you estimate potential burden or costs, explain how you 
arrived at the estimate that you provide.
    5. Provide specific examples to illustrate your concerns.
    6. Offer alternative ways to improve the science.
    7. Make sure to submit your comments by the deadline in this 
notice.
    8. To ensure proper receipt by EPA, be sure to identify the docket 
ID number assigned to this action in the subject line on the first page 
of your response. You may also provide the name, date, and Federal 
Register citation.

II. Background

A. Why is EPA Requiring Health Effects Testing on TCE?

    EPA proposed health effects testing under TSCA section 4(a) for a 
number of hazardous air pollutants (``HAPs'' or ``HAP chemicals''), 
including TCE in the Federal Register of June 26, 1996 (61 FR 33178) 
(FRL-4869-1), as amended in the Federal Register of December 24, 1997 
(62 FR 67466) (FRL-5742-2), and April 21, 1998 (63 FR 19694) (FRL-5780-
6). EPA's primary use of the data from this testing activity will be to 
implement several provisions of section 112 of the Clean Air Act (CAA), 
including determining residual risks (e.g., assessing risks remaining 
after imposition of technology-based emission standards (maximum 
achievable control technology or ``MACT'' standards)), estimating risks 
associated with accidental chemical releases, and determining whether 
or not subject chemicals should be removed (``delisted'') from the CAA 
section 112(b) HAPs list. Other important uses of the data obtained via 
this testing activity will be to: (1) Help in better informing 
communities and citizens about chemical hazards in their own 
localities; (2) assist state and local permitting authorities with 
establishing appropriate standards within their programs; and (3) help 
other EPA Program Offices and other Federal agencies (e.g., the Agency 
for Toxic Substances and Disease Registry (ATSDR), the National 
Institute for Occupational Safety and Health (NIOSH), the Occupational 
Safety and Health Administration (OSHA), and the Consumer Product 
Safety Commission (CPSC)) in assessing chemical risks and taking 
appropriate action(s) within their own programs and under the Federal 
statutes that they administer.

B. How is EPA Obtaining Health Effects Testing on TCE?

    In the proposed HAPs test rule, as amended, EPA identified the 
following testing needs for TCE: Acute toxicity, subchronic toxicity, 
developmental toxicity, reproductive toxicity, neurotoxicity, 
carcinogenicity, in vivo cytogenetics, and immunotoxicity to be 
conducted by the inhalation route of exposure.
    EPA also invited the submission of proposals regarding the 
performance of pharmacokinetics studies which would permit 
extrapolation from oral data to predict risk from inhalation exposure. 
Such proposals could provide the scientific basis for alternative 
testing to the testing proposed and form the basis for developing 
needed HAPs data via ECAs (61 FR 33178, June 26, 1996; 62 FR 67466, 
December 24, 1997). EPA uses ECAs to accomplish testing where a 
consensus is reached concerning the need for and scope of testing. The 
procedures for ECA negotiations are described at 40 CFR 790.22(b).
    In response to EPA's request for ECA proposals, the Dow Chemical 
Company; Vulcan Materials Company; Occidental Chemical Corporation; Oxy 
Vinyls, LP; Georgia Gulf Corporation; Westlake Chemical Corporation; 
PPG Industries, Inc.; Borden Chemicals and Plastics Operating Limited 
Partnership; and Formosa Plastics Corporation, U.S.A. (``the 
Companies''), under the auspices of the HAP Task Force, submitted a 
proposal for alternative testing of TCE that included physiologically 
based pharmacokinetics (PBPK) and model development to support route-
to-route extrapolation of extant studies acceptable to EPA and new 
testing to be conducted by the oral route (Ref. 1). On December 19, 
1997, EPA announced the initiation of ECA discussions to develop an 
acceptable alternative testing program for TCE and solicited the 
involvement of interested parties (62 FR 66628) (FRL-5632-2). These 
discussions resulted in an ECA for TCE which was announced in the 
Federal Register of June 15, 2000 (65 FR 37550) (FRL-6494-5). Under the 
TCE ECA alternative testing program (Ref. 2), these HAPs data needs are 
being addressed via an informed testing program that utilizes, wherever 
possible, extant data from acceptable studies performed by routes other 
than inhalation, testing by inhalation and the oral route, and 
development of PK/MECH data to support a computational dosimetry model 
to perform route-to-route extrapolations. The official public docket 
for the development of the TCE ECA is established under docket control 
number OPPTS-42198B, while the official public docket for the receipt 
of data under the TCE ECA is established under docket ID number OPPT-
2002-0056 (which is the continuation of OPPTS-42198B).

C. What Testing Does the ECA for TCE Require?

    The TCE ECA alternative testing program has four segments, as 
follows: Tier I HAPs testing; Tier I Program Review testing; EPA 
Program Review; and Tier II testing.
    1. Tier I HAPs testing. This testing consisted of the following 
endpoint testing, conducted by inhalation exposure, that EPA deemed 
necessary to meet certain data needs identified in the proposed HAPs 
test rule: Acute and subchronic toxicity. In addition, EPA determined 
that existing cytogenicity studies conducted by Mazzulo et al. (1986) 
and Doherty et al. (1996) were adequate at this time to characterize 
the mutagenicity of TCE (Refs. 3 and 4).
    2. Tier I Program Review testing. Under this segment of the TCE ECA 
alternative testing program, the test sponsor is to develop a 
computational dosimetry model, specific to TCE, for rats and mice, 
validate the model, and verify the model's ability to perform 
quantitative route-to-route extrapolations.
    In addition, the test sponsor is to develop PK/MECH data to support 
the application of the model for the endpoints listed in Tier II of the 
TCE ECA. Model development and data from this testing are subject to 
the EPA Program Review. Specifically, the PK/MECH data will be applied 
to support: (1) Oral-to-inhalation extrapolation of existing 
immunotoxicity data in mice administered TCE via drinking water (Ref. 
5); (2) oral-to-inhalation extrapolation of existing oral cancer 
bioassay data in mice administered TCE via corn oil gavage (Ref. 6); 
and (3) model simulations to demonstrate validation and verification of 
computational PBPK models for route-to-route extrapolation in order to

[[Page 63916]]

evaluate acceptability of oral drinking water exposure in rats for 
neurotoxicity testing, oral drinking water exposure in rats and mice 
for developmental toxicity testing, and oral drinking water exposure in 
rats for reproductive toxicity testing.
    3. EPA Program Review. The use of PK/MECH data and computational 
dosimetry modeling to support route-to-route extrapolation is a new 
approach for EPA's Office of Pollution Prevention and Toxics under the 
TSCA section 4 chemical testing program. It is essential to the success 
of the TCE ECA alternative testing program for EPA to ensure that the 
model and the PK/MECH data used to support the route-to-route 
extrapolations are of the highest quality. For this reason, a Program 
Review requirement was incorporated into the TCE ECA.
    The purpose of the EPA Program Review of the TCE ECA is to 
determine: (1) Whether it is feasible and appropriate to apply Tier I 
Program Review testing data and data from other studies acceptable to 
EPA to support computational route-to-route extrapolations for 
endpoints listed in the Tier II testing segment of the ECA; (2) whether 
the data from the Tier I Program Review testing segment provide a 
sufficient basis for conducting the endpoint testing and/or the 
computational route-to-route extrapolations specified in the Tier II 
testing segment; and (3) the nature and scope of any additional work 
that may be required before Tier II testing and application of the TCE 
model for route-to-route extrapolation reporting (e.g., development of 
additional PK/MECH data, modification to the TCE model).
    4. Tier II testing. This segment of the TCE ECA alternative testing 
program consists of endpoint testing by oral exposure for 
neurotoxicity, developmental toxicity and reproductive toxicity. This 
segment also includes application of the TCE model for quantitative 
route-to-route extrapolation reporting (oral to inhalation) for Tier II 
endpoint testing (neurotoxicity, developmental toxicity, reproductive 
toxicity) and similar computational extrapolation reporting for certain 
extant studies for immunotoxicity (Ref. 5) and carcinogenicity (Ref. 
6).

III. Next Steps

A. What is the Status of the Testing Program Developed in the ECA for 
TCE?

    Tier I HAPs testing for TCE is completed and reports for Tier I 
Program Review testing have been submitted by the Companies. Receipt of 
these submissions was announced in Federal Register notices of April 
10, 2002 (67 FR 17429) (FRL-6831-5); April 12, 2002 (67 FR 17996) (FRL-
6831-4); and August 14, 2002 (67 FR 53001) (FRL-7193-1) and are 
available in the EPA Docket Center (OPPTS-2002-0056). As described in 
Unit II.C.3., and stated in Part VI. of the TCE ECA, the next step is 
for EPA to conduct a Program Review on the data collected from the Tier 
I Program Review testing segment of the TCE ECA alternative testing 
program. The outcome from this EPA review will determine whether or not 
additional PK/MECH data and/or model development are needed before Tier 
II testing and computational dosimetry model reporting for route-to-
route extrapolations of Tier II endpoints can proceed as described in 
the TCE ECA.

B. Is there an Opportunity for Public Participation in EPA's Program 
Review?

    This notice of availability and request for comments on the 
Companies' Tier I Program Review testing reports titled: 
``Pharmacokinetics of 1,1,2-Trichloroethane in Rats and Mice'' and 
``Physiologically Based Pharmacokinetic Model Development, Simulations, 
and Sensitivity Analysis for Repeated Exposure to 1,1,2-
Trichloroethane'' provides an opportunity for public participation in 
the EPA Program Review of the TCE ECA. A description of EPA's 
objectives in conducting the Program Review for the TCE ECA alternative 
testing program is provided in Unit II.C.3.

C. What Happens at the Conclusion of EPA's Program Review?

    A description of the possible outcomes of the EPA Program Review is 
provided in Part VII. of the TCE ECA document (Ref. 2). Following the 
EPA Program Review, EPA will place in the official public docket for 
this action (under docket ID number OPPTS-2002--0056) a copy of each 
comment received, and a copy of the letter informing the HAP Task Force 
of the outcome from EPA's Program Review.

IV. References

    The official public docket for this action contains the following 
information:
    1. The HAP Task Force. Letter from Peter E. Voytek to Charles M. 
Auer with attachment titled: Proposal for Pharmacokinetics Study of 
1,1,2-Trichloroethane, November 22, 1996. (Available from docket 
control number OPPTS-42187B.)
    2. U.S. EPA, Enforceable Consent Agreement for 1,1,2-
Trichloroethane. September 30, 1999. (CAS No. 79-00-5) (Available from 
docket control number OPPTS-42198B.)
    3. Mazzulo, M., Colacci, A., Grilli, S., Prodi, G., and Arfellini, 
G. 1,1,2-Trichloroethane: evidence of genotoxicity from short-term 
tests. Japanese Journal of Cancer Research. 77:532-539. 1986.
    4. Doherty, A.T., Ellard, S., Parry, E.M., and Parry, J.M. An 
investigation into the activation and deactivation of chlorinated 
hydrocarbons to genotoxins in metabolically competent human cells. 
Mutagenesis. 11(3):247-274. 1996.
    5. Sanders, V.M., White, Jr., K.L., Shopp, Jr., G.M., and Musson, 
A.E. Humoral and cell-mediated immune status of mice exposed to 1,1,2-
trichloroethane. Drug and Chemical Toxicology. 8(5):357-372. 1985.
    6. National Cancer Institute (NCI). Bioassay of 1,1,2-
trichloroethane for possible carcinogenicity. Carcinogenesis: Technical 
Report Series No. 74. U.S. Department of Health, Education and Welfare, 
Public Health Service, National Institutes of Health. 1978.

List of Subjects

    Environmental protection, Hazardous chemicals.


    Dated: October 8, 2002.
Wardner G. Penberthy,
Acting Director, Chemical Control Division, Office of Pollution 
Prevention and Toxics.

[FR Doc. 02-26308 Filed 10-15-02; 8:45 am]
BILLING CODE 6560-50-S