Testing of Certain High Production Volume Chemicals, 13708-13735 [06-2483]

Agencies

• ENVIRONMENTAL PROTECTION AGENCY

[Federal Register Volume 71, Number 51 (Thursday, March 16, 2006)]
[Rules and Regulations]
[Pages 13708-13735]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 06-2483]



[[Page 13707]]

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Part III





Environmental Protection Agency





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40 CFR Parts 9 and 799



Testing of Certain High Production Volume Chemicals; Final Rule

Federal Register / Vol. 71, No. 51 / Thursday, March 16, 2006 / Rules 
and Regulations

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 9 and 799

[EPA-HQ-OPPT-2005-0033; FRL-7335-2]
RIN 2070-AD16


Testing of Certain High Production Volume Chemicals

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: EPA is promulgating a final rule under the Toxic Substances 
Control Act (TSCA) that requires manufacturers (including importers) 
and processors of 17 high production volume (HPV) chemicals to conduct 
acute toxicity, repeat dose toxicity, developmental and reproductive 
toxicity, genetic toxicity (gene mutations and chromosomal 
aberrations), ecotoxicity (in fish, Daphnia, and algae), and 
environmental fate (including 5 tests for physical chemical properties 
and biodegradation) testing. EPA has determined that each of the 17 
chemicals included in this final rule is produced in substantial 
quantities and that there is or may be substantial human exposure to 
each of them. Moreover, EPA has determined that there are insufficient 
data to reasonably determine or predict the effects on health or the 
environment of the manufacture, distribution in commerce, processing, 
use, or disposal of the chemicals, or any combination of these 
activities. EPA has concluded that this testing program is necessary 
and appropriate for developing such data. Data developed under this 
final rule will provide critical information about the environmental 
fate and potential hazards of these chemicals which, when combined with 
information about exposure and uses, will allow the Agency and others 
to evaluate potential health and environmental risks and take 
appropriate actions. Persons who export or intend to export any 
chemical included in this final rule, regardless of the form in which 
it is exported, are subject to the export notification requirements of 
TSCA section 12(b).

DATES: This final rule is effective on April 17, 2006. The 
incorporation by reference of certain publications listed in the rule 
is approved by the Director of the Federal Register as of April 17, 
2006. For purposes of judicial review, this final rule shall be 
promulgated at 1 p.m. eastern daylight/standard time on March 30, 2006.

ADDRESSES: Docket. EPA has established a docket for this action under 
docket identification (ID) number EPA-HQ-OPPT-2005-0033. All documents 
in the docket are listed on the regulations.gov web site. Although 
listed in the index, some information is not publicly available, i.e., 
Confidential Business Information (CBI) or other information whose 
disclosure is restricted by statute. Certain other material, such as 
copyrighted material, is not placed on the Internet and will be 
publicly available only in hard copy form. Publicly available docket 
materials are available either electronically at https://
www.regulations.gov or in hard copy at the OPPT Docket, EPA Docket 
Center (EPA/DC), EPA West, Rm. B102, 1301 Constitution Ave., NW., 
Washington, DC. The Public Reading Room is open from 8:30 a.m. to 4:30 
p.m., Monday through Friday, excluding legal holidays. The telephone 
number for the Public Reading Room is (202) 566-1744, and the telephone 
number for the OPPT Docket is (202) 566-0280.
    TSCA section 4 submissions. For submission instructions, see Unit 
IX. of the SUPPLEMENTARY INFORMATION.

FOR FURTHER INFORMATION CONTACT: For general information contact: Colby 
Lintner, Regulatory Coordinator, 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: TSCA-
Hotline@epa.gov.
    For technical information contact: Catherine Roman, Chemical 
Control Division (7405M), Office of Pollution Prevention and Toxics, 
Environmental Protection Agency, 1200 Pennsylvania Ave., NW., 
Washington, DC 20460-0001; telephone number: (202) 564-4780; e-mail 
address: roman.catherine@epa.gov.

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

    You may be potentially affected by this action if you manufacture 
(defined by statute to include import) or process any of the chemical 
substances that are listed in Table 2 in Sec.  799.5085(j) of the 
regulatory text. Any use of the term ``manufacture'' in this final rule 
will encompass ``import,'' unless otherwise stated. In addition, as 
described in Unit VI., any person who exports or intends to export any 
of the chemical substances in this final rule, regardless of the form 
in which it is exported, is subject to the export notification 
requirements in 40 CFR part 707, subpart D. Potentially affected 
entities may include, but are not limited to:
     Manufacturers (defined by statute to include importers) of 
one or more of the 17 subject chemical substances (NAICS codes 325 and 
324110), e.g., chemical manufacturing and petroleum refineries.
     Processors of one or more of the 17 subject chemical 
substances (NAICS codes 325 and 324110), e.g., chemical manufacturing 
and petroleum refineries.
    This listing is not intended to be exhaustive, but rather provides 
a guide for readers regarding entities likely to be affected by this 
action. Other types of entities not listed in this unit could also be 
affected. The North American Industry Classification System (NAICS) 
codes have been provided to assist you and others in determining 
whether this action might apply to certain entities. To determine 
whether you or your business may be affected by this action, you should 
carefully examine the applicability provisions in Unit V.E. and consult 
Sec.  799.5085(b) of the regulatory text. 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 Access Electronic Copies of this Document and Other 
Related Information?

    In addition to using the online docket system, you may access this 
Federal Register document electronically through the EPA Internet under 
the ``Federal Register'' listings at https://www.epa.gov/fedrgstr. A 
frequently updated electronic version of 40 CFR part 9 and part 799 is 
available on E-CFR Beta Site Two at https://www.gpoaccess.gov/ecfr.

II. Background

A. What Action is the Agency Taking?

    EPA is promulgating a final test rule under TSCA section 4(a)(1)(B) 
(15 U.S.C. 2603(a)(1)(B)) that requires manufacturers and processors of 
17 chemical substances to conduct acute toxicity, repeat dose toxicity, 
developmental and reproductive toxicity, genetic toxicity, ecotoxicity, 
and environmental fate testing. The chemicals are HPV chemicals, i.e., 
chemicals with a production/import volume equal to or greater than 1 
million pounds per year. A detailed discussion regarding efforts to 
enhance the availability of screening level hazard and environmental 
fate information about HPV chemicals can be found in a Federal Register 
document which published on December 26, 2000 (Ref. 1).
    The tests are screening level tests which in combination are known 
as the

[[Page 13709]]

Screening Information Data Set (SIDS) (see Unit II.D.). Some or all of 
these tests are required for a particular chemical substance, depending 
upon what data are already available for that substance.
    In the proposal to this final rule, published in the Federal 
Register of December 26, 2000, EPA proposed SIDS testing for 37 HPV 
chemicals (Ref. 2). Numerous comments were received on the proposed 
rule. In consideration of those comments, EPA changed some testing 
requirements for certain chemicals as explained in Unit III. As a 
result of recent commitments to a voluntary EPA testing program known 
as the HPV Challenge Program (see Unit II.C.), and updated production 
volume data (i.e., 2002 Inventory Update Rule (IUR) data) made 
available after the publication of the proposal preceding this final 
rule (i.e., the ``proposed rule''), EPA is requiring testing for 17 of 
the 37 chemicals originally proposed for testing in 2000. EPA's 
decision to not finalize testing requirements for the remaining 20 
chemicals is described in Unit VII.
    At a future date, EPA may propose testing for additional HPV 
chemicals as the Agency learns more about the chemicals with respect to 
human exposure, release, and sufficiency of the data and experience 
available on their potential hazards.

B. What is the Agency's Authority for Taking this Action?

    This final rule is being promulgated under TSCA section 4(a) (15 
U.S.C. 2603(a)), which directs EPA to require the development of data 
relevant to assessing whether activities associated with chemical 
substances and mixtures present an unreasonable risk of injury to 
health or the environment, when appropriate findings are made.
    Section 2(b)(1) of TSCA (15 U.S.C. 2603(b)(1)) states that it is 
the policy of the United States that:
    . . . adequate data should be developed with respect to the 
effect of chemical substances and mixtures on health and the 
environment and that the development of such data should be the 
responsibility of those who manufacture [which is defined by statute 
to include import] and those who process such chemical substances 
and mixtures[.]

    To implement this policy, TSCA section 4(a) mandates that EPA 
require by rule that manufacturers and/or processors of chemical 
substances and mixtures conduct testing if the Administrator finds 
that:
    (1)(A)(i) the manufacture, distribution in commerce, processing, 
use, or disposal of a chemical substance or mixture, or that any 
combination of such activities, may present an unreasonable risk of 
injury to health or the environment,
    (ii) There are insufficient data and experience upon which the 
effects of such manufacture, distribution in commerce, processing, 
use, or disposal of such substance or mixture or of any combination 
of such activities on health or the environment can reasonably be 
determined or predicted, and
    (iii) Testing of such substance or mixture with respect to such 
effects is necessary to develop such data; or
    (B)(i) a chemical substance or mixture is or will be produced in 
substantial quantities, and (I) it enters or may reasonably be 
anticipated to enter the environment in substantial quantities or 
(II) there is or may be significant or substantial human exposure to 
such substance or mixture,
    (ii) There are insufficient data and experience upon which the 
effects of the manufacture, distribution in commerce, processing, 
use, or disposal of such substance or mixture or of any combination 
of such activities on health or the environment can reasonably be 
determined or predicted, and(iii) Testing of such substance or 
mixture with respect to such effects is necessary to develop such 
data [.].

    If EPA makes these findings for a chemical substance or mixture, 
the Administrator shall require by rule that testing be conducted on 
that chemical substance or mixture. The purpose of the testing is to 
develop data about the substance's or mixture's health or environmental 
effects for which there is an insufficiency of data and experience, and 
which are relevant to a determination that the manufacture, 
distribution in commerce, processing, use, or disposal of the chemical 
substance or mixture, or any combination of such activities, does or 
does not present an unreasonable risk of injury to health or the 
environment.
    EPA need not limit the scope of testing required to the factual 
basis for the TSCA section 4(a)(1)(A)(i) or (B)(i) findings, as long as 
EPA finds that there are insufficient data and experience upon which 
the effects of the manufacture, distribution in commerce, processing, 
use, or disposal of such substance or mixture or any combination of 
such activities on health or the environment can be reasonably 
determined or predicted, and that testing is necessary to develop the 
data. This approach is explained in more detail in EPA's statement of 
policy for making findings under TSCA section 4(a)(1)(B) (frequently 
described as the ``B'' policy) (Ref. 3, pp. 28738-28739).
    In this final rule, EPA is using its broad TSCA section 4(a) 
authority to obtain data necessary to support the development of 
preliminary or ``screening level'' determinations of the effects on 
health and the environment from exposure to the 17 chemical substances 
specified in Table 2 in Sec.  799.5085(j) of the regulatory text. 
Following consideration of the public comments received by EPA on the 
proposed test rule (Ref. 2) and updated production volume information 
(i.e., 2002 IUR data), EPA is making the following findings for the 17 
chemical substances under TSCA section 4(a)(1)(B): They are produced in 
substantial quantities; there is or may be substantial human exposure 
to them; existing data are insufficient to determine or predict their 
health and environmental effects; and testing is necessary to develop 
such data.

C. Why is EPA Taking this Action?

    On April 21, 1998, EPA initiated a national effort to empower 
citizens with knowledge about the most widespread chemicals in 
commerce. A major objective of this effort is to make certain basic 
information about the environmental fate and potential health and 
environmental hazards associated with HPV chemicals available to the 
public. Mechanisms to collect or, where necessary, develop needed data 
on U.S. HPV chemicals include the voluntary HPV Challenge Program, 
certain international efforts, and TSCA section 4 rules.
    1. Voluntary HPV Challenge Program. The voluntary HPV Challenge 
Program, officially launched in late 1998, was created to ensure that a 
baseline set of data on approximately 2,800 HPV chemicals would be made 
available to the public. HPV chemicals are manufactured or imported in 
amounts equal to or greater than 1 million pounds per year and were 
identified for this program through data reported under the TSCA 
Inventory Update Rule (IUR) during 1990.
    EPA challenged U.S. manufacturers and importers of HPV chemicals to 
voluntarily sponsor chemicals in the Program. Sponsorship entails 
making screening-level health and environmental data available to the 
public. Public availability of these data, a fundamental principle of 
the Program, enables the public to know about the hazards associated 
with chemicals in their environment. The data set sought by the HPV 
Challenge Program is known as the Screening Information Data Set (SIDS) 
that was developed by the Organization for Economic Cooperation and 
Development (OECD). The SIDS provides an internationally agreed upon 
set of test data for screening high production volume chemicals for 
human and environmental hazards, and will allow the Agency and others 
to make an informed, preliminary

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judgment about the hazards of HPV chemicals.
    As part of their commitment to the HPV Challenge Program, sponsors 
submit data summaries of existing information along with a test plan 
that proposes a strategy to fill data gaps. Sponsors submit test plans 
for either individual chemicals or for a category of chemicals. A 
chemical category comprises a group of substances, usually similar in 
chemical structure, with a regular pattern of properties and effects. 
Data for chemicals in the category can be used to estimate the chemical 
properties and effects of other category members.
    A 120-day comment period begins when test plans and data summaries 
submitted directly to the HPV Challenge Program are posted to the 
Program website. It is at this time when all stakeholders--industry, 
environmental protection groups, animal welfare groups, private 
citizens, etc.--can comment on the data summary and test plan 
submissions. EPA comments on all of the submissions as well. Comments 
are important because sponsors consider this feedback when revising 
their test plans and data summaries. All comments are posted to the 
Program website for public availability.
    Since the Program's inception in 1998, industry chemical 
manufacturers and importers have participated in the Challenge by 
sponsoring over 2,200 chemicals. More than 400 companies and 100 
consortia have sponsored chemicals directly in the Program while 
additional companies/consortia have sponsored chemicals indirectly in 
an international counterpart to the HPV challenge Program, the 
International Council of Chemical Associations (ICCA) HPV Initiative. 
HPV chemicals that are not sponsored in the Program may be subject to a 
test rule under TSCA Section 4 because these chemicals lack needed 
testing. The voluntary HPV Challenge Program is further described in a 
Federal Register document which published on December 26, 2000 (Ref. 
1).
    2. Certain international efforts. The voluntary HPV Challenge 
Program is designed to make maximum use of scientifically adequate 
existing test data and to avoid unnecessary and duplicative testing of 
U.S. HPV chemicals. Therefore, EPA is continuing to participate in the 
voluntary international efforts, complementary to the voluntary HPV 
Challenge Program, that are being coordinated by the OECD to secure 
basic hazard information on HPV chemicals in use worldwide, including 
some of those on the U.S. (1990) HPV chemicals list (Ref. 4). This 
includes agreements to sponsor a U.S. HPV chemical under either the 
OECD HPV SIDS Program (Ref. 5), including sponsorship by OECD member 
countries beyond the United States, or the international HPV Initiative 
that is being organized by the International Council of Chemical 
Associations (ICCA) (Ref. 6).
    The OECD HPV SIDS Program includes information on the identity of 
each chemical, its uses, sources and extent of exposure; physical and 
chemical properties; environmental fate; and certain limited toxicity 
data for humans and the environment. The SIDS is not intended to 
describe a chemical thoroughly, but rather is intended to provide 
enough information to support an initial (or screening level) 
assessment and to assign a priority for further work, if necessary. The 
OECD HPV SIDS Program seeks the development of test data, if such data 
are not already available, related to six health and environmental 
effects endpoints for international HPV chemicals (see Unit II.D.). The 
SIDS data set has been internationally agreed upon by the 29 member 
countries of the OECD as providing the minimum data set required to 
make an informed preliminary judgment about the hazards of a given HPV 
chemical.
    The ICCA consists of representatives of chemical industry trade 
associations from the United States, Europe, Japan, Australia, Canada, 
Mexico, Brazil, New Zealand, and Argentina. The intended goal of the 
ICCA HPV Initiative was to complete screening-level hazard assessments 
on 1,000 ``high priority'' chemicals by the end of the year 2004. The 
progress of the ICCA HPV Initiative to date can be checked on ICCA's 
HPV Chemical Tracking System website at https://www.iccahpv.com/reports/
reportsmain.cfm. Most of the chemicals on the ICCA working list (Ref. 
6) are also U.S. HPV chemicals. The ICCA testing/assessment work will 
be tied directly to that under the OECD HPV SIDS Program and to the 
U.S. voluntary HPV Challenge Program and any associated TSCA section 4 
HPV SIDS rules. Any U.S. HPV chemicals that are handled under the OECD 
HPV SIDS Program or the ICCA HPV Initiative are considered by EPA to be 
``sponsored'' and are not anticipated to be addressed in the voluntary 
HPV Challenge Program unless the international commitments are not met. 
Nor does EPA intend to evaluate these chemicals for possible TSCA 
section 4 HPV SIDS rulemaking unless the international commitments are 
not met.
    3. TSCA rulemaking. U.S. data needs which remain unmet in the 
voluntary HPV Challenge Program or through international efforts may be 
addressed through TSCA section 4 rulemaking, such as this final rule, 
where EPA determines that the statutory findings can be made. This 
final rule is the first TSCA section 4 HPV SIDS rule, and addresses the 
unmet data needs of 17 chemicals.
    Data collected and/or developed under this final rule and the 
voluntary HPV Challenge Program, when combined with information about 
exposure and uses, will allow the Agency and others to better assess 
the potential risk to health and the environment from these chemicals. 
EPA intends to make the information collected under this final rule 
available to the public, other Federal agencies, and any other 
interested parties on its website (https://www.epa.gov/chemrtk/
volchall.htm) and in the public docket for this final rule identified 
under ADDRESSES. As appropriate, this information will be used to 
ensure a scientifically sound basis for risk assessment/management 
actions. This effort will serve to further the Agency's goal of 
identifying and controlling human and environmental risks as well as 
providing greater protection and knowledge to the public. By using the 
same approach to testing as that of the OECD Program, EPA is assuring 
that the data developed under this rule and the voluntary HPV Challenge 
Program will be comparable to the data being developed in other 
countries, thereby enabling an international sharing of data and the 
prevention of unnecessary and duplicative testing. See Refs. 1 and 2, 
pp. 81662-81664 for further information about the voluntary HPV 
Challenge Program and international efforts.

D. Why is EPA Focusing on HPV Chemicals and SIDS Testing?

    EPA is focusing on HPV chemicals, which it defines as being 
manufactured in amounts equal to or greater that 1 million pounds, 
because although those chemicals cover only about 11% of the TSCA 
Inventory of chemical substances (see TSCA sections 8(a) and 8(b)), 
using Inventory information available in 1988 (Ref. 10, p. 32296), that 
small percentage of the Inventory accounts for 95% of total chemical 
production in the United States.
    EPA is focusing on Screening Information Data Set (SIDS) testing 
because it is comprised of a battery of tests agreed upon by the 
international community through the OECD, of which the United States is 
a member country, as appropriate for screening HPV chemical substances 
for toxicity and produces information relevant to

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understanding the basic health and environmental hazards and fate of 
HPV chemicals. The six basic testing endpoints comprising this battery 
of tests, known as the SIDS, have been adopted by the OECD as the 
minimum required to screen HPV chemical substances for toxicity and 
environmental fate. The content of SIDS was agreed upon at the 13\th\ 
Joint Meeting of the OECD Chemicals Group and Management Committee of 
the Special Programme on the Control of Chemicals (Refs. 7 and 8). The 
United States believes these are the right tests for our domestic 
needs, i.e., screening U.S. HPV chemicals for health and environmental 
effects and environmental fate.
    SIDS testing evaluates the following six testing endpoints (Ref. 
5):
     Acute toxicity.
     Repeat dose toxicity.
     Developmental and reproductive toxicity.
     Genetic toxicity (gene mutations and chromosomal 
aberrations).
     Ecotoxicity (studies in fish, Daphnia, and algae).
     Environmental fate (including physical/chemical properties 
(melting point, boiling point, vapor pressure, n-octanol/water 
partition coefficient, and water solubility), photolysis, hydrolysis, 
transport/distribution, and biodegradation).
While data on the six SIDS endpoints do not fully measure a chemical's 
toxicity, they do provide a consistent minimum set of information that 
can be used to determine the relative hazards of chemicals and to judge 
if additional testing or assessment is necessary.

E. How Does EPA's HPV Work Relate to That of the OECD?

    As noted in Unit II.C.2., the OECD SIDS Program is complementary to 
the voluntary HPV Challenge Program. However, EPA's definition of an 
HPV chemical differs from that of the OECD. EPA defines an HPV chemical 
as having an annual production or importation volume of 1 million 
pounds or more. The OECD defines an HPV chemical as having an annual 
production volume of 2.2 million pounds (equivalent to 1 million 
kilograms (kg)) reported in any member country.
    The presence of a chemical on the OECD's list of HPV chemicals was 
and continues to be accepted by OECD member countries as providing a 
sufficient indicator of potential exposure to warrant testing at the 
SIDS level (Ref. 9).
    EPA, however, does not believe that a production volume threshold 
which is chosen for an international program on existing chemicals and 
which is the only trigger for entry into that program should be 
determinative of the threshold chosen for ``substantial production'' 
under TSCA section 4(a)(1)(B)(i). See EPA's ``B'' policy (Ref. 3). 
Among the reasons is that the TSCA section 4(a)(1)(B)(i) finding of 
substantial production is not the sole finding EPA must make to require 
testing based on TSCA section 4(a)(1)(B). EPA must also find that there 
is substantial release, or substantial or significant human exposure 
under TSCA sections 4(a)(1)(B)(i)(I) and (II). In addition, EPA must 
find that data are insufficient and testing is necessary under TSCA 
sections 4(a)(1)(B)(ii) and (iii). Accordingly, a finding that a 
chemical is produced in substantial quantities alone is not a 
sufficient basis to require testing under TSCA section 4.
    In response to EPA's proposed ``B'' policy (Ref. 10), both the 
American Chemistry Council (ACC, formerly the Chemical Manufacturers 
Association (CMA)) and the Society of the Plastics Industry, Inc. 
commented that EPA's proposed production volume threshold of 1 million 
pounds is a reasonable interpretation of ``substantial production'' 
under TSCA (Refs. 11 and 12). Additionally, they indicated that the 
OECD's 2.2 million pound threshold would be preferable to achieve 
consistency between EPA's activities under TSCA section 4 and the OECD 
HPV SIDS Program. Although the United States and OECD differ in their 
definition of an HPV chemical and what should trigger basic screening 
tests of an HPV chemical, both the U.S. and OECD HPV Programs are alike 
in their information needs for an HPV chemical. Both the U.S. and OECD 
HPV Programs have identified the SIDS battery of tests as the basic 
screening tests needed to provide enough information to support a 
screening level assessment of the health and environmental effects of a 
chemical.

F. Why is EPA Pursuing Hazard Information on HPV Chemicals?

    EPA found that, of those non-polymeric organic substances produced 
or imported in amounts equal to or greater than 1 million pounds per 
year based on 1990 IUR reporting, only 7% had a full set of publicly 
available and internationally recognized basic screening test data for 
health and environmental effects (Ref. 13). Of the over 2,800 U.S. HPV 
chemicals based on 1990 IUR data, 43% had no publicly available basic 
hazard data. For the remaining chemicals, limited amounts of the data 
were available. This lack of available hazard data compromises EPA's 
and others' ability to determine whether these HPV chemicals pose 
potential risks to human health or the environment, as well as the 
public's ability to know about the hazards of chemicals that may be 
found in their environment, their homes, their workplaces, and the 
products they buy.

G. What is the Role of this Final Rule and Any Future TSCA Section 4 
HPV SIDS Rulemaking with Regard to the Voluntary HPV Challenge Program?

    As indicated in the December 26, 2000 Federal Register document 
(Ref. 1) describing the voluntary HPV Challenge Program, EPA intends to 
use rulemaking under TSCA where appropriate to help fill data gaps not 
addressed as part of the voluntary HPV Challenge Program or 
international efforts. EPA does not intend at this time to evaluate 
U.S. HPV chemicals that have been or are being handled through the OECD 
HPV SIDS Program or under a complementary program being coordinated by 
the ICCA (Ref. 6) for screening level testing under TSCA section 4 HPV 
SIDS rulemaking, although the Agency may revisit this question if 
commitments under those international programs are not met. See Unit 
III.G. of Ref. 1 for more information on these programs. EPA is 
evaluating the extent to which additional nonsponsored HPV chemicals 
meet the threshold criteria for rulemaking under TSCA section 4.

H. How Will the Data Developed Under this Final Rule Be Used?

    The availability of hazard data on certain individual chemicals is 
fundamental to EPA's ability to accomplish its mission of environmental 
protection. Hazard data are used in risk assessment and risk 
management, and ultimately to inform the public and promote the 
pollution prevention ethic. Activities to ensure the availability of 
basic hazard information on HPV chemicals support EPA's objectives.
    EPA will use the data obtained from this final rule to support 
development of preliminary hazard and risk assessments for the 17 HPV 
chemicals subject to this rule. The data will also be used by EPA to 
set priorities for further testing that may produce hazard information 
on these chemicals that may be needed by EPA, other Federal agencies, 
the public, industry, and others, to support adequate risk assessments. 
As appropriate, this information will be used to ensure a 
scientifically sound basis for risk characterizations and risk 
management actions. As such, this effort will serve to further the 
Agency's goal of identifying and controlling human

[[Page 13712]]

and environmental risks as well as providing greater knowledge and 
protection to the public. In the past, EPA has used data from test 
rules to support such activities as the development of water quality 
criteria, Toxic Release Inventory (TRI) listings, chemical advisories, 
and reduction of workplace exposures.
    Finally, because the SIDS data to be developed under this final 
rule will be comparable to the type of data agreed to as being 
appropriate and being developed by the OECD HPV SIDS Program, the 
development of these data will enable an international sharing of data. 
As conceived by the OECD, the SIDS battery of tests can be used by 
governments and others worldwide to conduct an initial assessment of 
the hazards and risks posed by HPV chemicals and prioritize HPV 
chemicals to identify those in need of additional, more in-depth 
testing and assessment, as well as those of lesser concern. Not only 
can the data generated from this and any future TSCA section 4 HPV SIDS 
test rules contribute to the international effort, but also 
international SIDS testing and assessments can be used to fill the data 
gaps identified as part of the voluntary HPV Challenge Program. 
Additional detailed information is available on the SIDS website 
(https://cs3-hq.oecd.org/scripts/hpv) and EPA's voluntary HPV Challenge 
Program website (https://www.epa.gov/chemrtk/volchall.htm).
    Data collected or developed for each sponsored chemical in the 
voluntary HPV Challenge Program are provided in the format of a 
``robust'' (i.e., detailed) summary. A robust summary contains the 
technical information necessary to adequately describe an experiment or 
study and includes the objectives, methods, results, and conclusions of 
the full study report, which can either be an experiment or in some 
cases an estimation or prediction method. (See Ref. 14, also at https://
www.epa.gov/chemrtk/robsumgd.htm). A robust summary provides sufficient 
information to allow a technically qualified person to make an 
independent assessment of a given study without having to read the full 
study report, and thereby facilitates the evaluation of existing data 
and the identification of additional data needs. EPA suggests that 
existing data relevant to this final rule be submitted to the Agency in 
robust summary format and, for any data developed under this rule, that 
a robust summary of the final report for each specific test be 
submitted in addition to the final report itself (see Sec.  799.5085(i) 
of the regulatory text).

III. Response to Public Comments

    EPA received a number of comments in response to the proposal (Ref. 
2) to this final rule. A summary of those comments and EPA's response 
to each comment are presented in the document entitled Response to 
Public Comments (Ref. 40). Both the comments and EPA's Response to 
Public Comments (Ref. 40) are available in the public docket under 
ADDRESSES. The comments on the proposed test rule (Ref. 2) were 
submitted by the American Chemistry Council (ACC), American Petroleum 
Institute (API), Synthetic Organic Chemical Manufacturers Association 
(SOCMA), Center for Regulatory Effectiveness (CRE), Environmental 
Defense (ED), American Coke and Coal Chemicals Institute (ACCCI), Color 
Pigments Manufacturers Association, Inc. (CPMA), Ecological and 
Toxicological Association of Dyes and Organic Pigments Manufacturers 
(ETAD), Merisol USA LLC (Merisol), Ashland Distribution Company 
(Ashland), Dow Chemical Company (Dow), ExxonMobil Chemical Company 
(EMCC), Lonza Group, Dyno Nobel, Inc. (Dyno Nobel), Sciences 
International Inc.(SII), Institute of Makers of Explosives (IME), 
People for the Ethical Treatment of Animals (PETA), Physicians 
Committee for Responsible Medicine (PCRM), Doris Day Animal League 
(DDAL), The Humane Society of the United States (HSUS), Alternative 
Research & Development Foundation (ARDF), American Anti-Vivisection 
Society (AAVS), New England Anti-Vivisection Society (NEAVS), Silicones 
Environmental, Health and Safety Council (SEHSC), and numerous private 
citizens (Refs. 15-39).
    After review and analysis of the submitted comments, EPA made the 
following changes to the regulatory text as proposed in response to 
those comments:
    1. The tests for melting point, boiling point and vapor pressure 
are not required for 1,3-propanediol, 2,2-bis[(nitrooxy)methyl]-, 
dinitrate (ester) (CAS No. 78-11-5), also known as pentaerythritol 
tetranitrate (PETN). This change is further discussed in Unit VII.C.1. 
and in the document entitled Response to Public Comments (Ref. 40).
    2. The screening test for reproduction/developmental toxicity is 
not required for 2,4-hexadienoic acid, (2E,4E)- (CAS No. 110-44-1), 
also known as sorbic acid. This change is further discussed in Unit 
VII.C.2. and in the document entitled Response to Public Comments (Ref. 
40).
    3. The neutral red uptake basal cytotoxicity assay may be used to 
estimate the starting dose for the mammalian acute toxicity test. The 
test is included as a special condition in Table 3 in Sec.  799.5085(j) 
of the regulatory text. This change is further discussed in Unit V.A.4. 
and in the document entitled Response to Public Comments (Ref. 40).

IV. Findings

A. What is the Basis for EPA's Final Rule to Test These Chemical 
Substances?

    As indicated in Unit II.B., in order to promulgate a rule under 
TSCA section 4(a) requiring testing of chemical substances or mixtures, 
EPA must, among other things, make certain findings for those chemical 
substances or mixtures regarding either hazard (TSCA section 
4(a)(1)(A)(i)) or production and either chemical release or human 
exposure (TSCA section 4(a)(1)(B)(i)). EPA is requiring testing of the 
chemical substances included in this final rule based on its findings 
under TSCA section 4(a)(1)(B)(i) relating to ``substantial production'' 
and ``substantial human exposure,'' as well as findings under TSCA 
sections 4(a)(1)(B)(ii) and (iii) relating to sufficient data and the 
need for testing. The chemical substances included in this final rule 
are listed in Table 2 in Sec.  799.5085(j) of the regulatory text along 
with their CAS numbers.
    ``Substantial production'' of a chemical substance or mixture under 
TSCA section 4(a)(1)(B)(i) is generally interpreted by EPA to be 
aggregate production (including import) volume equaling or exceeding 1 
million pounds per year and exposure of 1,000 workers or more on a 
routine or episodic basis to a chemical substance or mixture is 
considered to be ``substantial exposure.'' See EPA's ``B'' policy (Ref. 
3) for further discussion on how EPA generally makes decisions under 
TSCA section 4(a)(1)(B)(i).
    EPA finds that, under TSCA section 4(a)(1)(B)(i), each of the 17 
chemical substances included in this final rule is produced in 
``substantial quantities'' and there is or may be ``substantial human 
exposure'' to each chemical substance (Ref. 41). In addition, under 
TSCA section 4(a)(1)(B)(ii), EPA finds that there are insufficient data 
and experience to reasonably determine or predict the effects of the 
manufacture, processing, or use of these chemical substances, or of any 
combination of such activities, on human health or the environment. EPA 
also finds that testing of the 17 chemical substances is necessary to 
develop such data (TSCA section 4(a)(1)(B)(iii)) (see Unit IV.E.).

[[Page 13713]]

 EPA has not identified any factors to cause the Agency to use 
decisionmaking criteria other than the general thresholds described in 
the ``B'' policy with respect to the chemicals included in this final 
rule.

B. Are These Chemical Substances Produced and/or Imported in 
Substantial Quantities?

    EPA finds that each of the chemical substances included in this 
final rule is produced and/or imported in an amount equal to or greater 
than 1 million pounds per year based on information gathered pursuant 
to the 2002 IUR (40 CFR part 710, subpart B). The 2002 IUR is the most 
recently available compilation of TSCA section 8(a) Inventory Update 
Reporting data, and the IUR data have been compiled into a database 
called the TSCA Chemical Update System. EPA also considered the fact 
that all of these chemicals were produced and/or imported above 1 
million pounds annually based on the 1990, 1994, and 1998 IUR. EPA 
concludes that the annual production volume of each chemical is 
``substantial'' as that term is used with reference to production in 
TSCA section 4(a)(1)(B)(i) (Ref. 3).

C. Are a Substantial Number of Workers Exposed to These Chemicals?

    EPA finds that the manufacture, processing, and use of the chemical 
substances included in this action result or may result in exposure to 
a substantial number of workers. These chemical substances are used in 
a wide variety of industrial applications which result in potential 
exposures to workers, as described in the exposure support document for 
this final rule (Ref. 41).
    EPA defines human exposure as the contact with a chemical or agent 
at the visible exterior of a person (i.e., skin and openings into the 
body such as mouth and nostrils) (Ref. 42, p. 22891). Worker exposure 
is the human exposure to a chemical or agent that occurs while a person 
is working. Worker exposure may have various causes, with chemical 
releases being a common cause of exposure. Chemical manufacturing and 
processing plants can release chemicals from pumps as fugitive 
emissions, from reactor and condenser vents as stack emissions, in the 
form of a vapor and/or as a particulate. Diffusion and air currents may 
carry a chemical throughout the plant and workers may breathe air 
containing the chemical, resulting in exposures. Certain human 
activities such as manually transferring a chemical from one container 
to another may also cause exposures.
    Each of the chemicals in this final rule was identified in the 
National Occupational Exposure Survey (NOES) as having a total worker 
exposure of 1,000 workers or more (Ref. 41). EPA concludes that an 
exposure of 1,000 workers or more to a chemical substance is or may be 
``substantial'' as that term is used with reference to ``human 
exposure'' in TSCA section 4(a)(1)(B)(i) (Ref. 3).

D. Do Sufficient Data Exist for These Chemical Substances?

    As discussed in Unit II.D., data on SIDS testing endpoints, 
including acute toxicity, repeat dose toxicity, developmental and 
reproductive toxicity, genetic toxicity (gene mutations and chromosomal 
aberrations), ecotoxicity (tests in fish, Daphnia, and algae), and 
environmental fate (five tests for physical/chemical properties 
(melting point, boiling point, vapor pressure, n-octanol/water 
partition coefficient, and water solubility) and biodegradation), are 
necessary in ascertaining the health and environmental effects of the 
17 chemicals in this final rule. EPA has determined that for the 17 
chemicals for which testing is required under this final rule, there 
are either no data available on SIDS testing endpoints or, where there 
is some information, these data are insufficient (See Unit II.D. and 
II.E.). Therefore, existing data are insufficient to reasonably 
determine or predict the effects on human health that may result from 
exposures to the chemical substances included in this final rule during 
the manufacturing, processing, or use of the subject chemical 
substances. EPA also sought existing information on the SIDS testing 
endpoints of chemical fate and ecotoxicity and found it to be 
insufficient. EPA undertook this evaluation because once the 
Administrator has made a finding under TSCA section 4(a)(1), EPA may 
require any type of health or environmental effects testing necessary 
to address unanswered questions about the effects of a chemical (Ref. 
2, p. 81660). The finding for insufficient data is based on the results 
of searches for data on SIDS endpoints by EPA (Ref. 13) and ACC (Ref. 
43), and EPA's review of studies/data identified by commenters in 
response to the proposal or identified by EPA after the publication of 
the proposal to this final rule. The studies and data submitted or 
identified subsequent to the proposal were found to be sufficient for 
some proposed tests of certain chemicals and those tests are not 
required for those chemicals in this final rule (See Unit VII.C.). 
Table 2 of Sec.  799.5085(j) of the regulatory text lists the SIDS 
endpoint tests for each of the remaining 17 chemicals for which no data 
are currently available to the Agency or, where some information is 
available, the data are not sufficient.
    In the proposal to this final rule, EPA encouraged the submission 
of existing data on SIDS testing endpoints which are relevant to 
characterizing the hazard of those chemicals for which testing was 
proposed. All such submitted information was carefully evaluated by EPA 
in the development of the final testing requirements in this rule. 
However, if persons required to test under this final rule become aware 
of additional relevant scientifically adequate existing data (including 
structure-activity relationships (SAR) information or a scientifically 
defensible category approach) and submit this information to EPA at any 
time before testing is initiated, the Agency would consider such data 
to determine if they satisfy the testing requirement and would take 
appropriate necessary action to ensure that the testing in this rule is 
no longer required. In fact, they may submit such information as a 
requested modification to the testing requirements under 40 CFR 790.55 
at anytime as long as the request is made at least 60 days before the 
reporting deadline for the test in question.

E. Is Testing Necessary for These Chemical Substances?

    As discussed in Unit IV.D., the lack of sufficient data for these 
17 chemicals compromises EPA's and others' ability to determine whether 
each chemical poses an unreasonable risk to human health or the 
environment. EPA believes that conducting SIDS testing for the 17 
subject chemical substances is necessary to provide data and experience 
upon which the effects of the manufacture, distribution in commerce, 
processing, use, or disposal of the chemical substances or of any 
combination of such activities on health or the environment can 
reasonably be determined or predicted. EPA has determined that testing 
is necessary in order to obtain these relevant data.
    EPA will use the data obtained from this final rule to support 
development of preliminary hazard assessments for these 17 HPV 
chemicals and to set priorities for obtaining exposure information and 
further testing that will produce more definitive hazard information 
where needed. Such additional information is needed by EPA, other 
Federal agencies, the public, industry, and others to ensure that 
adequate risk assessments can be conducted on these chemicals. EPA has

[[Page 13714]]

used data from test rules to support such activities as the development 
of water quality criteria, TRI listings, chemical advisories, and input 
for actions resulting in reduction of workplace exposures. (See Unit 
II.C. thru II.G.).

V. Final Rule

A. What Testing is Being Required in this Action?

    EPA is requiring specific testing and reporting requirements for 
the chemical substances listed in Table 2 in Sec.  799.5085(j) of the 
regulatory text. The testing requirements for each chemical are denoted 
by alphanumeric symbols in Table 2 in Sec.  799.5085(j) of the 
regulatory text. Table 3 in Sec.  799.5085(j) of the regulatory text 
provides the key to identify the tests denoted by the alphanumeric 
symbols and lists special conditions which might apply when conducting 
some of those tests. The test methods listed in Table 3 in Sec.  
799.5085(j) of the regulatory text are grouped according to the 
endpoint that they address. The following endpoints and test standards 
are required under this final rule; also discussed in this Unit V.A. 
are the special conditions which EPA has identified and is requiring 
for several of the required test standards.
    1. Physical/chemical properties.

Melting Point: American Society for Testing and Materials (ASTM) E 
324 (capillary tube) (Ref. 44).
Boiling Point: ASTM E 1719 (ebulliometry) (Ref. 45).
Vapor Pressure: ASTM E 1782 (thermal analysis) (Ref. 46).
n-Octanol/Water Partition Coefficient:
     Method A (40 CFR 799.6755--shake flask).
     Method B (ASTM E 1147--liquid chromatography) (Ref. 47).
     Method C (40 CFR 799.6756--generator column).
Water Solubility:
     Method A: (ASTM E 1148--shake flask) (Ref. 48).
     Method B: (40 CFR 799.6784--shake flask).
     Method C: (40 CFR 799.6784--column elution).
     Method D: (40 CFR 799.6786--generator column).

    EPA proposed determining the melting point of all 17 chemicals in 
this final rule using the method ASTM E 324. Since the publication of 
the proposal to this final rule, ASTM has indicated on its website, 
https://www.astm.org/cgi-bin/SoftCart.exe/index.shtml?E+mystore, that 
ASTM E 324 has been withdrawn. To quote the ASTM rationale for the 
withdrawal of ASTM E 324:
    The standard utilizes old, well-developed technology; it is 
highly unlikely that any additional [changes] and/or modifications 
will ever be pursued by the E15 [committee]. The time and effort 
needed to maintain these documents detracts from the time available 
to develop new standards which use modern technology (Ref. 49).

    Note that withdrawal of the method by ASTM means only that ASTM no 
longer continues to develop and improve the method. It does not mean 
that ASTM no longer considers the method to be valid. ASTM still makes 
the method available for informational purposes and it can still be 
purchased from ASTM at the address listed in Sec.  799.5085(h) of the 
regulatory text. EPA concludes that ASTM's withdrawal of E 324 does not 
have negative implications on the validity of the method; therefore, 
EPA is still requiring, for those chemicals for which melting points 
determinations are needed, that melting points be determined according 
to the method ASTM E 324.
    For the n-octanol/water partition coefficient and water solubility 
endpoints, EPA is requiring that certain ``special conditions'' be 
considered by test sponsors in determining the appropriate test method 
that would be used from among those included for these endpoints in 
Table 3 in Sec.  799.5085(j) of the regulatory text.
    For the ``n-octanol/water partition coefficient (log 10 basis)'' 
endpoint, also known as log Kow, the test method required, 
if any, will be determined by the test substance's estimated log 
Kow. EPA provides three methods for measuring the 
substance's log Kow, but prior to selecting an appropriate 
method to use, if any, EPA is recommending that the log Kow 
be quantitatively estimated by using the method described in the 
article entitled Atom/Fragment Contribution Method for Estimating 
Octanol-Water Partition Coefficients (Ref. 50). EPA is recommending 
that the Kow be estimated in recognition of the fact that, 
depending on the chemical substance's log Kow, one or more 
test methods can be expected to provide adequate information for 
determining the log Kow. In general, EPA believes that the 
more hydrophobic a subject chemical is, the less well Method A (40 CFR 
799.6755--shake flask) will work, and that Method B (ASTM E 1147--
liquid chromotography) and Method C (40 CFR 799.6756--generator column) 
become more suitable, especially Method C. Whether the test sponsor 
chooses to quantitatively estimate the log Kow or not, EPA 
requires that the test sponsor provide with the final study report the 
underlying rationale for the test method selected to measure log 
Kow. The required test methods have been developed to meet a 
wide variety of needs and, as such, are silent on experimental 
conditions related to pH. Therefore, EPA highly recommends that all 
required log Kow tests be conducted at pH 7 to ensure 
environmental relevance. The required test methods and estimated log 
Kow ranges that determine which test method must be used for 
this endpoint for a given chemical are shown in Table 1 of this unit. 
The ranges of the estimated log Kows have been modified 
slightly since the proposal to eliminate the overlap of ranges stated 
in the proposal.

[[Page 13715]]



      Table 1.--Test Requirements for the n-Octanol/water Partition
                          Coefficient Endpoint
------------------------------------------------------------------------
                                   Test requirements
        Testing category            and references    Special conditions
------------------------------------------------------------------------
Physical/chemical properties      n-Octanol/water     n-Octanol/water
                                   partition           partition
                                   coefficient (log    coefficient or
                                   10 basis) or log    log Kow:
                                   Kow:               Which method is
                                  The appropriate      required, if any,
                                   log Kow test, if    is determined by
                                   any, must be        the test
                                   selected from       substance's
                                   those listed in     estimated log Kow
                                   this column--see    as follows:
                                   special            log Kow <0: no
                                   conditions in the   testing required.
                                   adjacent column..  log Kow range 0-1:
                                  Method A: 40 CFR     Method A or B.
                                   799.6755 (shake    log Kow range >1-
                                   flask).             4: Method A or B
                                   Method B: ASTM E    or C.
                                   1147 (liquid       log Kow range >4-
                                   chromatography).    6: Method B or C.
                                   Method C: 40 CFR   log Kow >6: Method
                                   799.6756            C.
                                   (generator         Test sponsors are
                                   column).            required to
                                                       provide in the
                                                       final study
                                                       report the
                                                       underlying
                                                       rationale for the
                                                       method selected.
                                                       In order to
                                                       ensure
                                                       environmental
                                                       relevance, EPA
                                                       highly recommends
                                                       that the selected
                                                       study be
                                                       conducted at pH
                                                       7.
------------------------------------------------------------------------

    For the ``water solubility'' endpoint, the test method, if any, 
will be determined by the test substance's estimated water solubility. 
EPA recommends that water solubility be quantitatively estimated prior 
to initiating this study. One recommended method for estimating water 
solubility is described in the article entitled Improved Method for 
Estimating Water Solubility From Octanol/Water Partition Coefficient 
(Ref. 51). EPA requires that test sponsors provide in the final study 
report the underlying rationale for the test standard selected for this 
endpoint. The required test methods have been developed to meet a wide 
variety of needs and, as such, are silent on experimental conditions 
related to pH. Therefore, EPA highly recommends that all required water 
solubility tests be conducted at pH 7 to ensure environmental 
relevance. The estimated water solubility ranges that EPA proposed for 
use in selecting an appropriate test standard have been modified 
slightly since the proposal to eliminate overlaps. The estimated water 
solubility ranges that EPA is requiring in this final rule to select an 
appropriate test standard are shown in Table 2 of this unit.

      Table 2.--Test Requirements for the Water Solubility Endpoint
------------------------------------------------------------------------
                                   Test requirements
        Testing category            and references    Special conditions
------------------------------------------------------------------------
Physical/chemical properties      Water solubility:   Water solubility:
                                  The appropriate     Which method is
                                   method to use, if   required, if any,
                                   any, to test for    is determined by
                                   water solubility    the test
                                   must be selected    substance's
                                   from those listed   estimated water
                                   in this column--    solubility. Test
                                   see special         sponsors are
                                   conditions in the   required to
                                   adjacent column..   provide in the
                                  Method A: ASTM E     final study
                                   1148 (shake         report the
                                   flask).             underlying
                                  Method B: 40 CFR     rationale for the
                                   799.6784 (shake     method selected.
                                   flask).             In order to
                                  Method C: 40 CFR     ensure
                                   799.6784 (column    environmental
                                   elution).           relevance, EPA
                                  Method D: 40 CFR     highly recommends
                                   799.6786            that the selected
                                   (generator          study be
                                   column).            conducted at pH
                                                       7.
                                                      >5,000 milligrams/
                                                       liters (mg/L) :
                                                       Method A or B.
                                                      >10 mg/L--5,000 mg/
                                                       L: Method A, B,
                                                       C, or D.
                                                      >0.001 mg/L--10 mg/
                                                       L: Method C or D.
                                                      <=0.001 mg/L: No
                                                       testing required.
------------------------------------------------------------------------

    2. Environmental fate and pathways.

Inherent Biodegradation: ASTM 1625 (semicontinuous activated sludge 
test) (Ref. 52) or
ISO 9888 (Zahn-Wellens Method) (Ref. 53).

Either method may be used, and no special conditions apply.
    3. Aquatic toxicity.

Test Group 1: Acute toxicity to fish (ASTM E 729) (Ref. 54).
Acute toxicity to Daphnia (ASTM E 729) (Ref. 54).
Toxicity to plants (algae) (ASTM E 1218) (Ref. 55).
Test Group 2: Chronic toxicity to Daphnia (ASTM E 1193) (Ref. 56).
Toxicity to plants (algae) (ASTM E 1218) (Ref. 55).

    For the ``aquatic toxicity'' endpoint, the OECD HPV SIDS Program 
recognizes that, for certain chemicals, acute toxicity studies are of 
limited value in assessing the substances' aquatic toxicity. This issue 
arises with respect to chemicals with high log Kow values. 
In such cases, toxicity is unlikely to be observed over the duration of 
acute toxicity studies because of reduced uptake and the extended 
amount of time required for such substances to reach toxic 
concentrations in the test organism. For such situations, the OECD HPV 
SIDS Program recommends use of chronic toxicity testing in Daphnia in 
place of acute toxicity testing in fish and Daphnia. EPA is requiring 
that the aquatic toxicity testing requirement be determined based on 
the test substance's measured log Kow as determined by using 
the approach outlined in Unit V.A.1., in the discussion of ``n-octanol/
water partition coefficient,'' and in Table 3 in Sec.  799.5085(j) of 
the regulatory text. For test substances determined to have a log 
Kow of less than 4.2, one or more of the following tests 
(described as ``Test Group 1'' in Table 3 in Sec.  799.5085(j) of the 
regulatory text) are required: Acute toxicity to fish (ASTM E 729), 
Acute toxicity to Daphnia (ASTM E 729), and Toxicity to plants (algae) 
(ASTM E 1218). For test substances determined to have a log 
Kow that is greater than or equal to 4.2, one or both of the 
following tests (described as ``Test Group 2'' in Table 3 in Sec.  
799.5085(j) of the regulatory text) are required: Chronic toxicity to 
Daphnia (ASTM E 1193) and Toxicity to plants (algae) (ASTM E 1218). As 
outlined in Table 3 in Sec.  799.5085(j) of the regulatory text, 
depending on the testing required in Test Group 1, the Test Group 2 
chronic Daphnia test may substitute for either or both the acute

[[Page 13716]]

fish toxicity test and the acute Daphnia test.
    EPA recognizes that in some circumstances, acute aquatic toxicity 
testing (Test Group 1) may be relevant for certain chemical substances 
having a log Kow equal to or greater than 4.2. Using SAR, a 
log Kow of 4.2 corresponds with a fish bioconcentration 
factor (BCF) of about 1,000 (Refs. 57-59). A chemical with a fish BCF 
value of 1,000 or more is characterized as having a tendency to 
accumulate in living organisms relative to the concentration of the 
chemical in the surrounding environment (Ref. 60). For the purposes of 
this final rule, EPA's use of a log Kow equal to or greater 
than 4.2 (which corresponds with a fish BCF value of 1,000) is 
consistent with the approach taken in the Agency's proposed (Ref. 61) 
and final (Ref. 62) Policy Statement under TSCA section 5 entitled 
Category for Persistent, Bioaccumulative, and Toxic New Chemical 
Substances. EPA has also used a measured BCF that is equal to or 
greater than 1,000 or, in the absence of a BCF, a log Kow 
value equal to or greater than 4.3 to help define the potential of a 
new chemical substance to cause significant adverse environmental 
effects (Ref. 63). EPA considers the difference between the log 
Kow of 4.3 used with new chemical substances (Ref. 63) and 
the log Kow value of 4.2 cited in this final TSCA section 4 
test rule to be negligible.
    Chemical substances that are dispersible in water (e.g., 
surfactants, detergents, aliphatic amines, and cationic dyes) may have 
log Kow values greater than 4.2 and may still be acutely 
toxic to aquatic organisms. To deal with such chemicals, EPA is 
recommending that test sponsors who wish to conduct Test Group 1 
studies on chemicals with a log Kow greater than or equal to 
4.2 submit to EPA for approval a written request to conduct Test Group 
1 studies 90 days prior to conducting such studies. EPA solicited 
public comment on this approach as well as other alternative approaches 
in this area but did not receive comments on this matter.
    4. Mammalian toxicity--acute.

Acute Inhalation Toxicity (rat): Method A (40 CFR 799.9130)
Acute Oral Toxicity (rat): Method B (ASTM E 1163 or 40 CFR 
799.9110(d)(1)(i)(A)) (Ref. 64).

    For the ``mammalian toxicity--acute'' endpoint, EPA is requiring 
that certain ``special conditions'' be considered in determining the 
appropriate test method that would be used from among those included 
for this endpoint in Table 3 in Sec.  799.5085(j) of the regulatory 
text. The OECD HPV SIDS Program recognizes that for most chemical 
substances, the oral route of administration will suffice for this 
endpoint. However, consistent with the approach taken under the 
voluntary HPV Challenge Program, EPA is requiring that for test 
substances that are gases at room temperature (25[deg]C), the acute 
mammalian toxicity study be conducted using inhalation as the exposure 
route (described as Method A (40 CFR 799.9130) in Table 3 in Sec.  
799.5085(j) of the regulatory text). For all other chemicals (i.e., 
those that are either liquids or solids at room temperature), EPA is 
requiring that the mammalian acute toxicity testing be conducted via 
oral administration using an ``Up/Down'' test method (described as 
Method B (ASTM E 1163 or 40 CFR 799.9110(d)(1)(i)(A)) in Table 3 in 
Sec.  799.5085(j) of the regulatory text). Consistent with the 
voluntary HPV Challenge Program, EPA is allowing the use of the neutral 
red uptake basal cytotoxicity assay to select the starting dose for the 
acute oral toxicity test as noted in Unit III. and discussed in the 
document Response to Public Comments (Ref. 40). This test is included 
as a special condition in Table 3 in Sec.  799.5085(j) of the 
regulatory text.
    5. Mammalian toxicity--genotoxicity.

Gene Mutations:
Bacterial Reverse Mutation Test (in vitro): 40 CFR 799.9510
Chromosomal Damage:
In Vitro Mammalian Chromosome Aberration Test