[Federal Register Volume 82, Number 138 (Thursday, July 20, 2017)]
[Rules and Regulations]
[Pages 33726-33753]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-14337]



[[Page 33725]]

Vol. 82

Thursday,

No. 138

July 20, 2017

Part III





Environmental Protection Agency





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40 CFR Part 702





Procedures for Chemical Risk Evaluation Under the Amended Toxic 
Substances Control Act; Procedures for Prioritization of Chemicals for 
Risk Evaluation Under the Toxic Substances Control Act; Guidance To 
Assist Interested Persons in Developing and Submitting Draft Risk 
Evaluations Under the Toxic Substances Control Act; Notice of 
Availability; Final Rules and Notice

  Federal Register / Vol. 82 , No. 138 / Thursday, July 20, 2017 / 
Rules and Regulations  

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 702

[EPA-HQ-OPPT-2016-0654; FRL-9964-38]
RIN 2070-AK20


Procedures for Chemical Risk Evaluation Under the Amended Toxic 
Substances Control Act

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: As required under section 6(b)(4) of the Toxic Substances 
Control Act (TSCA), EPA is issuing a rule that establishes a process 
for conducting risk evaluations to determine whether a chemical 
substance presents an unreasonable risk of injury to health or the 
environment, without consideration of costs or other non-risk factors, 
including an unreasonable risk to a potentially exposed or susceptible 
subpopulation, under the conditions of use. This process incorporates 
the science requirements of the amended statute, including best 
available science and weight of the scientific evidence. Risk 
evaluation is the second step, after Prioritization, in a new process 
of existing chemical substance review and management established under 
recent amendments to TSCA. This rule identifies the steps of a risk 
evaluation process including: scope, hazard assessment, exposure 
assessment, risk characterization, and finally a risk determination. 
This process will be used for the first ten chemical substances 
undergoing evaluation from the 2014 update of the TSCA Work Plan for 
Chemical Assessments (to the maximum extent practicable). Chemical 
substances designated as High-Priority Substances during the 
prioritization process and those chemical substances for which EPA has 
initiated a risk evaluation in response to a manufacturer request, will 
always be subject to this process. The final rule also includes the 
required ``form and criteria'' applicable to such manufacturer 
requests.

DATES: This final rule is effective September 18, 2017.

ADDRESSES: The docket for this action, identified by docket 
identification (ID) number EPA-HQ-OPPT-2016-0654, is available at 
http://www.regulations.gov or at the Office of Pollution Prevention and 
Toxics Docket (OPPT Docket), Environmental Protection Agency Docket 
Center (EPA/DC), West William Jefferson Clinton Bldg., Rm. 3334, 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. Please review the visitor instructions and additional information 
about the docket available at http://www.epa.gov/dockets.

FOR FURTHER INFORMATION CONTACT:
    For technical information contact: Susanna W. Blair, Immediate 
Office, Office of Pollution Prevention and Toxics, Environmental 
Protection Agency, 1200 Pennsylvania Ave. NW., Washington, DC 20460-
0001; telephone number: (202) 564-4321; email address: 
[email protected].
    For general information contact: The TSCA-Hotline, ABVI-Goodwill, 
422 South Clinton Ave., Rochester, NY 14620; telephone number: (202) 
554-1404; email address: [email protected].

SUPPLEMENTARY INFORMATION: 

I. Executive Summary

A. Does this action apply to me?

    EPA is primarily establishing requirements on the Agency. However, 
this rule also includes the process and criteria that manufacturers 
(including importers) must follow when they request an Agency-conducted 
risk evaluation on a particular chemical substance. This action may, 
therefore, be of interest to entities that are manufacturing or 
importing, or may manufacture or import a chemical substance regulated 
under TSCA (e.g., entities identified under North American Industrial 
Classification System (NAICS) codes 325 and 324110). Since other 
entities may also be interested, the Agency has not attempted to 
describe all the specific entities and corresponding NAICS codes for 
entities that may be interested in or affected by this action.

B. What action is the Agency taking?

    EPA is establishing, by rule, the process by which the Agency will 
conduct risk evaluations on chemical substances under TSCA. The rule 
identifies the necessary components of a risk evaluation, including a 
scope (including a conceptual model and an analysis plan), a hazard 
assessment, an exposure assessment, a risk characterization, and a risk 
determination. The rule also establishes the process by which 
manufacturers would request an Agency-conducted risk evaluation, and 
the criteria by which the EPA will evaluate such requests. This rule 
also incorporates the statutory science requirements, including best 
available science and weight of the scientific evidence.

C. What is the Agency's authority for taking this action?

    EPA is issuing this rule pursuant to the authority in TSCA section 
6(b)(4), as amended (15 U.S.C. 2605(b)(4)). See also the discussion in 
Units II.A. and B.

D. What are the estimated incremental impacts of this action?

    The incremental impacts of this action are the result of the 
process and requirements that manufacturers (including importers) must 
perform if they elect to submit a chemical substance for a risk 
evaluation. EPA has estimated the potential burden and costs associated 
with the proposed requirements for submitting a request for an Agency-
conducted risk evaluation on a particular chemical substance which is 
available in the docket, is discussed in Unit V. and is briefly 
summarized here. (Ref. 1).
    The total estimated annual burden is 419.2 hours and $282,861, 
which is based on an estimated per request burden of 83.8 hours.
    In addition, EPA's evaluation of the potential costs associated 
with this action is discussed in Unit V. Since this rule focuses on the 
activities that a manufacturer must perform, the estimated incremental 
costs are expected to be de minimis.

II. Background

A. Statutory Requirements for Risk Evaluation

    TSCA section 6(b)(4) requires EPA to establish, by rule, a process 
to conduct risk evaluations. Specifically, EPA is directed to use this 
process to ``determine whether a chemical substance presents an 
unreasonable risk of injury to health or the environment, without 
consideration of costs or other non-risk factors, including an 
unreasonable risk to a potentially exposed or susceptible subpopulation 
identified as relevant to the risk evaluation by the Administrator 
under the conditions of use.'' 15 U.S.C. 2605(b)(4)(A). TSCA sections 
6(b)(4)(A) through (H) enumerate the deadlines and minimum requirements 
applicable to this process, including provisions that direct which 
chemical substances must undergo evaluation, the development of 
criteria for manufacturer-requested evaluations, the minimum components 
of an Agency risk evaluation, and the timelines for public comment and 
completion of the risk evaluation. The law also requires

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that EPA operate in a manner that is consistent with the best available 
science and make decisions based on the weight of the scientific 
evidence. 15 U.S.C. 2625(h) and (i).
    1. Chemical substances to undergo risk evaluation. TSCA section 
6(b) identifies the chemical substances that are subject to this 
process; these are: (1) The ten chemical substances the Agency was 
required to identify from the 2014 update to the TSCA Work Plan within 
the first 180 calendar days after the signing of TSCA); (2) the 
chemical substances determined to be High-Priority Substances through 
the prioritization process published elsewhere in this Federal 
Register; and (3) chemicals selected in response to a manufacturer 
request that meets the criteria established by this rule. 15 U.S.C. 
2605(b)(4)(C). Assuming EPA receives a sufficient number of compliant 
requests, the statute specifies that EPA shall ensure that the number 
of manufacturer-requested evaluations is not less than 25 percent and 
not more than 50 percent of the number of the on-going ``High 
Priority'' risk evaluations. 15 U.S.C 2605(b)(4)(E). Since the number 
of manufacturer-requested evaluations is expressed as a percentage of 
the number of High-Priority Substance evaluations, not as a percentage 
of the total, the number of manufacturer-requested evaluations will 
likely comprise between \1/5\ and \1/3\ of the number of total ongoing 
evaluations, assuming a sufficient number of compliant requests are 
received. Any manufacturer requested risk evaluations for chemical 
substances on the 2014 update of the TSCA Work Plan (Ref. 2) will be 
granted at the discretion of the Administrator, and are exempt from the 
percentage limitations.
    2. Manufacturer-requested risk evaluations. TSCA section 6(b)(4)(C) 
directs EPA to establish the ``form and manner'' and ``criteria'' that 
govern manufacturer requests that EPA conduct a risk evaluation on a 
substance that they manufacture. EPA has broad discretion to establish 
these criteria, but relatively less discretion over whether to grant 
requests that comply with EPA's criteria. EPA must grant any request if 
it determines that it complies with EPA's criteria, until the statutory 
minimum of 25 percent has been met. Assuming EPA receives requests in 
excess of this threshold, EPA interprets this provision to grant EPA 
discretion to determine whether to grant further requests, up to the 
maximum 50 percent level. In such circumstances, EPA is directed to 
give preference to manufacturer requests for which EPA determines that 
restrictions imposed by one or more states have the potential to 
significantly impact interstate commerce, or health or the environment. 
15 U.S.C. 2605(b)(4)(E)(iii).
    3. Components of a risk evaluation. The statute identifies the 
minimum components EPA must include in all chemical substance risk 
evaluations. For each risk evaluation, EPA must publish a document that 
outlines the scope of the risk evaluation that EPA expects to conduct, 
which includes the hazards, exposures, conditions of use, and the 
potentially exposed or susceptible subpopulations that EPA expects to 
consider. 15 U.S.C 2605(b)(4)(D). The statute further provides that the 
scope of the risk evaluation must be published no later than six months 
after the initiation of the risk evaluation. Id.
    Each risk evaluation must also: (1) Integrate and assess available 
information on hazards and exposure for the conditions of use of the 
chemical substance, including information on specific risks of injury 
to health or the environment and information on potentially exposed or 
susceptible subpopulations; (2) describe whether aggregate or sentinel 
exposures were considered and the basis for that consideration; (3) 
take into account, where relevant, the likely duration, intensity, 
frequency, and number of exposures under the conditions of use; and (4) 
describe the weight of the scientific evidence for the identified 
hazards and exposure. 15 U.S.C. 2605(b)(4)(F)(i), and (iii)-(v). The 
risk evaluation must not consider costs or other non-risk factors. 15 
U.S.C. 2605(b)(4)(F)(ii).
    4. Science requirements. TSCA section 26 requires that, to the 
extent that EPA makes a decision based on science under TSCA sections 
4, 5, or 6, EPA must use scientific standards and base those decisions 
on the best available science and on the weight of the scientific 
evidence. 15 U.S.C. 2625(h) and (i). TSCA does not however explicitly 
define either of these terms. Section 26(h) lists factors for the 
Agency to consider, as applicable, in employing best available science. 
These are: (1) The extent to which the scientific information, 
technical procedures, measures, methods, protocols, methodologies, or 
models employed to generate the information are reasonable for and 
consistent with the intended use of the information; (2) the extent to 
which the information is relevant for the Administrator's use in making 
a decision about a chemical substance or mixture; (3) the degree of 
clarity and completeness with which the data, assumptions, methods, 
quality assurance, and analyses employed to generate the information 
are documented; (4) the extent to which the variability and uncertainty 
in the information, or in the procedures, measures, methods, protocols, 
methodologies, or models, are evaluated and characterized; and (5) the 
extent of independent verification or peer review of the information or 
of the procedures, measures, methods, protocols, methodologies, or 
models. As statutory requirements, they apply to EPA's decisions under 
TSCA sections 4, 5, and 6.
    5. Timeframe. TSCA requires that the risk evaluation process last 
no longer than three years, with a possible additional six-month 
extension. 15 U.S.C. 2605(b)(4)(G).
    6. Opportunities for public participation. The statute requires 
that the Agency allow for no less than a 30-day public comment period 
on the draft risk evaluation, prior to publishing a final risk 
evaluation. 15 U.S.C. 2605(b)(4)(H).
    7. Metals and metal compounds. When evaluating metals or metal 
compounds, EPA must use the March 2007 Framework for Metals Risk 
Assessment of the Office of the Science Advisor (Ref. 3) or a successor 
document that addresses metals risk assessment and is peer- reviewed by 
the Science Advisory Board.
    8. Non-vertebrate testing. Although not an explicit section 6 
requirement, TSCA imposes new requirements on EPA regarding the 
reduction of vertebrate testing. Amendments to TSCA section 4 require 
EPA to ``. . . reduce and replace, to the extent practicable, [. . .] 
the use of vertebrate animals in the testing of chemical substances . . 
.'' and to develop a strategic plan to promote such alternative test 
methods. 15 U.S.C. 2603(h). Under the risk evaluation process, EPA may 
require development of new information relating to a chemical 
substance. Prior to developing this information EPA must first take 
into account reasonably available existing information, and 
additionally, must encourage and facilitate the use of test methods 
that reduce or replace the use of vertebrate animals, group chemicals 
into categories to reduce testing, and encourage the formation of 
industry consortia to jointly conduct testing and other data gathering 
to avoid unnecessary duplication of tests.

B. Overview of Final Rule

    This final rule incorporates all the elements required by statute, 
as discussed in Unit II.A., some additional criteria the Agency plans 
to include and

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consider, clarifications for greater transparency, and additional 
procedural steps to ensure effective and transparent implementation. In 
response to public comments on the proposal, EPA is, among other 
things: (1) Adding direct references in the final rule to acknowledge 
the Agency's commitment to implementing the best available science and 
weight of the scientific evidence provisions in TSCA, (2) codifying the 
Agency's commitment to interagency collaboration, (3) allowing 
manufacturers to limit their requests for EPA-conducted risk 
evaluations to one or more specified conditions of use, and (4) 
allowing for risk determinations to be made on individual conditions of 
use or categories of conditions of use at any time once the Final Scope 
is published.
    EPA intends that the provisions of this rule be severable. In the 
event that any individual provision or part of this rule is 
invalidated, EPA intends that this would not render the entire rule 
invalid, and that any individual provisions that can continue to 
operate will be left in place.

III. Discussion of Final Rule and Response to Comments

A. Policy Objectives

    The risk evaluation process under TSCA will provide the basis for 
the EPA's determination as to whether a chemical substance presents an 
unreasonable risk of injury to health or the environment. The overall 
objective of this action is to codify the process by which the Agency 
evaluates risks from chemical substances under TSCA section 6. In this 
rule, the Agency details those components of TSCA risk evaluation and 
key factors that EPA deems are necessary to consider in each risk 
evaluation to ensure that the public has a full understanding of how 
risk evaluations will be conducted and to provide predictability in how 
they will be conducted. However, EPA is not establishing highly 
detailed provisions that will address every eventuality or possible 
consideration that might arise. Due to the rapid advancement of the 
science of risk evaluation and the science and technology that inform 
risk evaluation, this rule seeks to balance the need for the risk 
evaluation procedures to be transparent, without unduly restricting the 
specific science that will be used to conduct the evaluations, allowing 
the Agency flexibility to adapt and keep current with changing science 
as it conducts TSCA evaluations into the future.

B. Scope of Evaluations

    TSCA requires risk evaluations to determine whether or not a 
chemical substance presents an unreasonable risk of injury to health or 
the environment under the conditions of use, with conditions of use 
being defined as ``the circumstances, as determined by the 
Administrator, under which a chemical substance is intended, known, or 
reasonably foreseen to be manufactured, processed, distributed in 
commerce, used, or disposed of.'' 15 U.S.C. 2602(4).
    In the proposed rule, EPA explained that it interpreted TSCA to 
require that risk evaluations encompass all manufacture, processing, 
distribution in commerce, use, and disposal activities that constitute 
the conditions of use within the meaning of TSCA section 3. EPA further 
proposed that the conditions of use would need to encompass all known, 
intended, and reasonably foreseen activities associated with the 
subject chemical substance. EPA also noted, however, that a use or 
other activity constitutes a condition of use under the definition only 
if EPA determines that it does, and that EPA has authority to exercise 
judgment in making its determination of whether a condition of use is 
known, intended, or reasonably foreseen.
    This was one of the issues on which EPA received the most comments. 
Comments covered a number of considerations regarding conditions of 
use: How the Agency will define ``the conditions of use'', how the 
Agency will scope conditions of use (e.g., are there conditions of use 
which will not be included in the Scope of the risk evaluation for one 
reason or another), and finally how the Agency will treat the 
conditions of use identified in the scope, in the final risk 
determination. EPA discusses the first two considerations in this unit; 
the third consideration will be discussed in the risk determination 
Unit III.G.1.e.
    In defining conditions of use, many commenters raised concern about 
EPA's interpretation that ``the conditions of use'' must include ``all 
conditions of use.'' Concerns were raised in this regard was 
specifically about the ability of EPA to meet the statutory risk 
evaluation deadlines if all intended, known and reasonably foreseen 
activities must be considered conditions of use, and that attempting to 
identify every activity relating to the chemical substance was 
unnecessary and impractical. Concerns were also raised about ensuring 
that EPA can act promptly to address any unreasonable risks identified 
for particular conditions of use. Commenters who agreed with the 
proposed interpretation of ``all conditions of use'' stated that the 
law in a number of locations signals the intent that EPA evaluate all 
activities associated with the chemical. The identified locations 
include the section on Final Agency Action which states that decisions 
will be on a ``chemical substance'' without mention of condition of 
use, indicating that EPA must consider all conditions of use (15 U.S.C. 
2605(i)), and the requirement to account for the ``likely duration, 
intensity, frequency, and number of exposures under the conditions, 
where relevant'' (15 U.S.C. 2605(b)(4)(F)(iv)), which refers to the 
consideration of whether a combination of activities involving the 
chemical substance presents a risk, and therefore EPA must look at the 
full spectrum of the activities associated with a chemical (all 
intended, known, or reasonably foreseen manufacturing, processing, 
distribution, use and disposal).
    As EPA acknowledged in the proposal, different interpretations of 
the statute are possible. Given the strength and variety of the 
concerns presented in the comments, EPA has reevaluated its proposal. 
Accordingly, EPA went back to the direction on risk evaluation provided 
in section 6(b) of the statute and legislative history, and developed 
an approach to the term, ``the conditions of use'' that is firmly 
grounded in the law, while accounting for the various policy 
considerations necessary for effective implementation of section 6. 
EPA's final approach is informed in part by the legislative history of 
the amended TSCA, which explicitly states that the Agency is given the 
discretion to determine the conditions of use that the Agency will 
address in its evaluation of the priority chemical, in order to ensure 
that the Agency's focus is on the conditions of use that raise the 
greatest potential for risk. See, June 7, 2016 Cong Rec, S3519-S3520.
    In sum, EPA's overall objective of this rule is to ensure that it 
is able to focus on conducting a timely, relevant, high-quality, and 
scientifically credible evaluation of a chemical substance as a whole, 
and that it always includes an evaluation of the conditions of use that 
raise greatest potential for risk. EPA wants also to ensure that the 
Agency can effectively assess, and where necessary, regulate chemical 
substances, within the statutory deadlines. These same principles will 
also serve to guide EPA's implementation of the procedures.
    To begin, EPA will identify the ``circumstances'' that constitute 
the ``conditions of use'' for each chemical substance on a case-by-case 
basis. TSCA

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defines a chemical's ``conditions of use'' as ``the circumstances, as 
determined by the Administrator, under which a chemical substance is 
intended, known, or reasonably foreseen to be manufactured, processed, 
distributed in commerce, used, or disposed of.'' 15 U.S.C. 2602(4). 
While EPA interprets this as largely a factual determination--i.e., EPA 
is to determine whether a chemical substance is actually involved in 
one or more of the activities listed in the definition--the 
determination will inevitably involve the exercise of some discretion. 
As EPA interprets the statute, the Agency is to exercise that 
discretion consistent with the objective of conducting a technically 
sound, manageable evaluation to determine whether a chemical 
substance--not just individual uses or activities--presents an 
unreasonable risk. In that regard, EPA will be guided by its best 
understanding, informed by legislative text and history, of the 
circumstances of manufacture, processing, distribution in commerce, use 
and disposal Congress intended EPA to consider in risk evaluations.
    For most chemical substances EPA expects to make this determination 
primarily during the prioritization of a chemical substances. For 
chemicals that are the subject of a manufacturer request (which are not 
subject to prioritization), EPA intends to make this determination as 
part of the process for determining whether the request satisfies EPA's 
criteria, as discussed in greater detail in Unit III.G.
    Although EPA intends this to primarily be a case-by-case 
determination, as discussed in greater detail in Unit III.B.1, based on 
legislative history, statutory structure and other evidence of 
Congressional intent, EPA has identified certain activities that may 
generally not be considered to be conditions of use. As EPA gains 
experience in conducting risk evaluations, EPA may determine that other 
activities do not constitute conditions of use, based on the same type 
of analysis of Congressional intent. Second, in developing the scope of 
the risk evaluation, TSCA section 6(b)(4)(D) requires EPA to identify 
``the conditions of use that the Agency expects to consider in a risk 
evaluation,'' suggesting that EPA is not required to consider all 
conditions of use. Consequently, EPA may, on a case-by-case basis, 
exclude certain activities that EPA has determined to be conditions of 
use in order to focus its analytical efforts on those exposures that 
are likely to present the greatest concern, and consequently merit an 
unreasonable risk determination. For example, EPA may, on a case-by-
case basis, exclude uses that EPA has sufficient basis to conclude 
would present only ``de minimis'' exposures. This could include uses 
that occur in a closed system that effectively precludes exposure, or 
use as an intermediate. During the scoping phase, EPA may also exclude 
a condition of use that has been adequately assessed by another 
regulatory agency, particularly where the other agency has effectively 
managed the risks. EPA elaborates further on this step in Unit III.B.2.
    EPA intends to identify any conditions of use excluded during these 
first and second steps in the draft scope, along with the basis for 
EPA's preliminary determination, to provide the public with an 
opportunity to comment on the exclusions. The final scope, which 
specifies the conditions of use that EPA expects to consider in the 
risk evaluation, will also identify whether particular conditions of 
use have been excluded as a result of this process, along with the 
Agency's rationale.
    Finally, consistent with its original proposal, EPA may conduct its 
risk evaluations in stages. While the proposal only addressed the 
situation in which EPA determined that risk mitigation was necessary to 
address an unreasonable risk from a chemical substance under certain 
conditions of use, EPA has extended the logic in the final rule to 
apply whenever EPA has sufficient information to support a 
determination as to whether a chemical substance presents an 
unreasonable risk under particular conditions of use. Thus, at any 
point after EPA has issued its final scope document, in cases where EPA 
has sufficient information to determine whether or not the chemical 
substance presents an unreasonable risk under particular conditions of 
use, the Agency may issue an early determination for that subset of 
conditions of use, while EPA continues to evaluate the remaining 
conditions of use. All early determinations would be portions of the 
final, complete risk evaluation and would therefore be made using the 
procedures applicable to TSCA risk evaluations established in this 
rule. This would include the requirement that EPA publish a draft risk 
evaluation for no less than a 60-day public comment period, and the 
regulatory requirement for peer review. This may result in separate 
peer reviews for the separate determinations.
    In the interest of efficiency, EPA envisions that, in general, it 
would attempt to identify the subset of conditions of use that are 
candidates for an early determination as part of the draft scope 
document. In such cases, EPA may publish its draft risk evaluation for 
public comment along with the final Scope document. Depending on the 
information received during the comment period, EPA would either 
determine that it needed to continue to evaluate those conditions of 
use, or proceed to issue final determinations for those conditions of 
use.
    1. Exclusions from the Definition of Conditions of Use. As noted, 
the statute grants EPA the discretion to determine the circumstances 
that are appropriately considered to be the chemical's ``conditions of 
use.'' In exercising that discretion, for example, EPA would not 
generally consider that a single unsubstantiated or anecdotal statement 
(or even a few isolated statements) on the internet that a chemical can 
be used for a particular purpose would necessitate concluding that this 
represented part of the chemical substance's ``conditions of use.'' As 
a further example, although the definition could be read literally to 
include all intentional misuses (e.g., inhalant abuse), as a ``known'' 
or ``reasonably foreseen'' activity in some circumstances, EPA does not 
generally intend to include such activities in either a chemical 
substance's prioritization or risk evaluation. EPA's judgment is 
supported by the legislative history, and public comment suggesting 
that ``the term `conditions of use' is not intended to include 
`intentional misuse' of chemicals.'' See, for example Senate Report 
114-67, page 7. Without these exclusions, the concept of ``conditions 
of use'' would likely result in no meaningful limitation on EPA risk 
evaluations, and risk evaluations could present unmanageable 
challenges--an outcome that EPA does not expect Congress intended.
    Similarly, the statute is ambiguous as to whether the conditions of 
use identified by EPA should include the circumstances associated with 
activities that do not reflect ongoing or prospective manufacturing, 
processing, or distribution, which EPA will refer to as ``legacy 
uses.'' The statute is also ambiguous as to disposals from such uses 
(e.g., the future disposal of insulation that contains a chemical 
substance that is no longer manufactured, processed, or distributed for 
use in insulation), which EPA will call ``associated disposal,'' and 
disposals that have already occurred (e.g., a chemical substance 
currently in a landfill or in groundwater), which EPA will call 
``legacy disposal.'' No statutory text expressly addresses these 
issues. The absence of express statutory

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text on legacy use, associated disposal, and legacy disposal, as well 
as the plain language in ``conditions of use'' charging EPA to 
determine the circumstances appropriately considered to be the 
``conditions of use,'' leads the Agency to resolve the statutory 
ambiguity by considering all the tools of statutory interpretation 
(e.g., reliance on legislative history, and general maxims of statutory 
construction).
    EPA interprets the mandates under section 6(a)-(b) to conduct risk 
evaluations and any corresponding risk management to focus on uses for 
which manufacturing, processing, or distribution in commerce is 
intended, known to be occurring, or reasonably foreseen to occur (i.e., 
is prospective or on-going), rather than reaching back to evaluate the 
risks associated with legacy uses, associated disposal, and legacy 
disposal, and interprets the definition of ``conditions of use'' in 
that context. For instance, the conditions of use for purposes of 
section 6 might reasonably include the use of a chemical substance in 
insulation, where the manufacture, processing, or distribution in 
commerce for that use is prospective or on-ongoing, but would not 
include the use of the chemical substance in previously installed 
insulation, if the manufacture, processing or distribution for that use 
is not prospective or on-going. In other words, EPA interprets the risk 
evaluation process of section 6 to focus on the continuing flow of 
chemical substances from manufacture, processing and distribution in 
commerce into the use and disposal stages of their lifecycle. EPA 
believes the statute is better interpreted to focus on the prospective 
flow of the chemical substance. That said, in a particular risk 
evaluation, EPA may consider background exposures from legacy use, 
associated disposal, and legacy disposal as part of an assessment of 
aggregate exposure or as a tool to evaluate the risk of exposures 
resulting from non-legacy uses.
    Overall, EPA has determined that the statutory text better supports 
a prospective interpretation. Section 3 defines the ``conditions of 
use'' as ``the circumstances, as determined by the Administrator, under 
which a chemical substance is intended, known, or reasonably foreseen 
to be manufactured, processed, distributed in commerce, used, or 
disposed of.'' (emphasis added). The ``to be'' phrasing suggests that 
the term is focused prospectively. Moreover, throughout the legislative 
history, there are a number of references to TSCA as a statute for the 
regulation of chemicals ``in commerce,'' suggesting the intent to focus 
on current activities associated with chemicals rather than legacy 
issues. In addition, EPA notes that section 6(a) of TSCA does not 
authorize EPA to directly regulate non-commercial use, meaning that EPA 
would not have an effective tool to address risks found to arise from 
uses in consumer settings if there were no on-going commercial 
manufacture, processing or distribution.
    EPA's interpretation finds support in the general presumption 
against construing a statute (or implementing regulation) to be 
retroactive or have retrospective effect. While Congress can make a law 
retroactive, absent clear intent from Congress, courts will not hold a 
statute to be retroactive, or uphold an agency regulation that seeks to 
have such an effect. Republic of Iraq v. Beaty, 556 U.S. 848 at 862 
(2009) (citing to Landgraf v. Usi Film Products, 511 U.S. 244, 267-68 
(1994). See also, Bowen v. Georgetown Univ. Hosp., 488 U.S. 204, 208 
(1988) (citing several sources). This general presumption also extends 
to statutes that affect ``vested rights and past transactions,'' which 
have been considered to be retroactive (or ``retrospective'') in 
nature. E.g., Landgraf, 511 U.S. at 268-69, 296 (quotation marks and 
citations omitted) (citing several other Supreme Court cases using 
alternate formulations of this principle).
    Finally, even if these activities were not excluded from the 
definition of conditions of use, EPA generally expects that it would 
exercise its discretion under section 6(b)(4)(D) to exclude them from 
the scope of risk evaluations, as discussed in section B.2., below.
    2. Conditions of use that may be excluded from the Scope of the 
risk evaluation. In exercising its discretion under section 6(b)(4)(D), 
EPA believes it is important for the Agency to have the discretion to 
make reasonable, technically sound scoping decisions in light of the 
overall objective of determining whether chemical substances in 
commerce present an unreasonable risk. For example, EPA intends to 
exercise discretion in addressing circumstances where the chemical 
substance subject to scoping is unintentionally present as an impurity 
in another chemical substance that is not the subject of the pertinent 
scoping. In some instances, it may be most appropriate from a technical 
and policy perspective to evaluate the potential risks arising from a 
chemical impurity within the scope of the risk evaluations for the 
impurity itself. In other cases, it may be more appropriate to evaluate 
such risks within the scope of the risk evaluation for the separate 
chemical substances that bear the impurity. (EPA has previously taken 
an analogous approach, in requiring chemical testing of certain 
chemical substances under 40 CFR part 766, based on the potential for 
the chemical substance to be manufactured in such a manner as to be 
contaminated with dioxins.) In still other cases, EPA may choose not to 
include a particular impurity within the Scope of any risk evaluation, 
where EPA has a basis to foresee that the risk from the presence of the 
impurity would be `de minimis' or otherwise insignificant. Finally, as 
stated, EPA received a number of comments offering ideas regarding 
conditions of use that should not be considered in a risk evaluation, 
for example, on the ground that certain uses are not ``reasonably 
foreseen.'' Some of the many uses that commenters asked to be excluded 
from a risk evaluation include: Uses where other agencies hold 
jurisdiction, misuse, illegal use, speculative future conditions of 
use, uses that are inconsistent with labeling requirements or PPE 
requirements, chemicals used in articles or replacement parts, uses 
that are inconsistent with manufacturers' instructions, accidental 
conditions of use of a chemical, or uses where residuals from an 
industrial process are completely destroyed. In connection with these 
suggestions, several of these commenters also requested that EPA 
clearly define precisely how the Agency will determine whether a 
condition of use is ``known or reasonably foreseen.''
    At this stage of EPA's implementation, EPA believes that it would 
be premature to definitively exclude a priori specific conditions of 
use from risk evaluation. For the same reason, EPA believes that it 
would be premature to establish a specific test or restrictive 
definition to determine whether a condition of use is ``reasonably 
foreseen.'' The Agency is committed to exercising its discretion to 
determine the conditions of use in a reasonable manner and will not 
base this determination upon hypotheticals or conjecture. The 
identification of ``reasonably foreseen'' conditions of use will 
necessarily be a case by case determination, and will be highly fact-
specific. Sources of facts to support such determinations may include 
known activities associated with similar chemicals, knowledge of a 
chemical's properties that may allow it to replace a function currently 
being performed by non-chemical means, or information on research and 
development activities applying a chemical substance to a particular 
new use. It is reasonable to foresee a condition of use, for example, 
where facts suggest the activity is not

[[Page 33731]]

only possible but, over time under proper conditions, probable.
    As EPA gains experience in conducting risk evaluations, it will 
likely develop additional scoping principles, consistent with the 
discussion in this preamble. EPA has issued Guidance to Assist 
Interested Persons in Developing and Submitting Draft Risk Evaluation 
Under the Toxic Substances Control Act and section 26(l) requires EPA 
to reevaluate guidance every 5 years. This document may be the 
appropriate venue for EPA to provide additional transparency regarding 
conditions of use included/excluded as a part of scoping as the Agency 
becomes better versed in this process.

C. General Provisions

    The general provisions of the final rule outline the purpose, 
scope, applicability and enforcement of this rule.

D. Definitions

    TSCA defines a number of key terms necessary for interpretation of 
the new law, and the statutory definitions apply to this rule. To 
increase clarity and transparency, EPA has included a number of 
additional definitions in the rule. In the proposed rule, EPA asked for 
comments specifically on whether to codify definitions of terms 
including ``best available science,'' ``weight-of-the-scientific 
evidence,'' ``sufficiency of information,'' ``unreasonable risk,'' and 
``reasonably available information,'' among others. EPA identified the 
sources of possible definitions, and in some instances provided 
extensive discussion of its current interpretation of the terms. EPA 
also encouraged commenters to suggest alternative definitions the 
Agency should consider for codification in this rule.
    EPA received a number of comments on this subject; in general, many 
comments acknowledged that there are numerous ways these phrases can be 
defined and ultimately implemented. Many also acknowledged that the 
science is changing and the Agency must maintain flexibility to 
implement advancing and novel science. Some commenters agreed with 
EPA's proposed conclusion that not defining the terms allows for 
flexibility to change as the science changes and that strict 
definitions may impede TSCA implementation. A number of comments 
discussed the legislative history behind these terms, specifically the 
fact that previous versions of the statute did include some of these 
definitions and that they were removed in the final version. Other 
commenters argued that since these terms are not defined in the statute 
and there is no requirement in the statute to define them by rule, 
there was no Congressional intent to codify definition of these terms 
in this rule. Additionally, it was reasoned that any codified 
definitions would apply not only to TSCA section 6 actions and rules, 
but also to TSCA sections 4 and 5, and potentially other applications 
outside of TSCA. They argued this makes it much more difficult to 
develop and implement universally appropriate definitions.
    A significant number of commenters did encourage EPA to define, or 
at the very least, to provide additional principles and concepts that 
will be applied to implement these terms, arguing that this will add 
transparency and better articulate how EPA will implement the 
scientific criteria of the statute. Some commenters stated that the 
definitions of these terms have not changed with changing science, only 
the data sets used to inform the definitions. Other commenters, who 
agreed these terms do have a number of different meanings believed it 
was therefore more important to define them in this rule so the public 
knew which definition would be applied. Commenters also stated these 
terms are the ``cornerstones'' of risk evaluations under TSCA, and 
definitions were necessary to alleviate potential confusion in 
implementation of these requirements. Many commenters who believed it 
is necessary for EPA to define these terms did include proposed 
definitions and/or descriptions.
    EPA has chosen to only define terms in this final rule that appear 
in the statute, including best available science, reasonably available 
information, and weight of the scientific evidence, among others. EPA 
agrees with many of the public comments that the definitions of these 
terms in the final rule will instill confidence, increase transparency, 
and provide the public with assurance that EPA will adhere to the 
requirements of the statute. Based on review of the public comments 
received, EPA has also revised the proposed definitions to increase 
their clarity, while also adding additional discussion in the preamble.
    EPA will first discuss definitions included in the regulation (in 
the order they appear in the regulation), and then will discuss 
additional terms that have not been codified, but are important 
components of the risk evaluation process.
    1. Aggregate exposure. TSCA requires EPA, as a part of the risk 
evaluation, to document whether the Agency has considered aggregate 
exposure, and the basis for that decision. 15 U.S.C. 2605(b)(4)(F)(ii). 
This term is not statutorily defined; however, EPA has defined 
aggregate exposure to be consistent with current Agency policies and 
practices. ``Aggregate exposure'' means the combined exposures to an 
individual from a single chemical substance across multiple routes and 
across multiple pathways (Ref.4). This is consistent with the proposed 
rule and consistent with agency policy.
    2. Best available science. Section 26(h) of amended TSCA requires 
that ``in carrying out sections 4, 5, and 6, to the extent that the 
Administrator makes a decision based on science, the Administrator 
shall use scientific information, technical procedures, measures, 
methods, protocols, methodologies, or models, employed in a manner 
consistent with the best available science.'' As stated, many 
commenters encouraged EPA to codify a definition of the ``best 
available science.'' In response to these comments, EPA determined that 
`best available science' is an integral component of section 6 risk 
evaluations, and has incorporated a definition of `best available 
science' into the regulatory text. The first part of the definition 
originates from the Safe Drinking Water Act (SDWA) (42 U.S.C. 300f et 
seq.) and is also included in the EPA's Information Quality Guidance 
(Ref. 5). The SDWA definition was cited by a number of commenters, and 
EPA agrees this definition, already in use at the Agency, is 
appropriate. The second part of the definition is taken directly from 
TSCA section 26(h), which identifies mandatory approaches to fulfilling 
the science standards under TSCA. By basing its definition of `best 
available science' on these two sources, EPA believes that the Agency 
is remaining consistent with the current approach already used Agency-
wide, while also acknowledging the specific standards under TSCA.
    The final rule defines ``best available science'' as science that 
is reliable and unbiased. This involves the use of supporting studies 
conducted in accordance with sound and objective science practices, 
including, when available, peer reviewed science and supporting studies 
and data collected by accepted methods or best available methods (if 
the reliability of the method and the nature of the decision justifies 
use of the data). Additionally, EPA will consider as applicable:--

--The extent to which the scientific information, technical procedures, 
measures, methods, protocols, methodologies, or models employed to 
generate the information are

[[Page 33732]]

reasonable for and consistent with the intended use of the information;
--The extent to which the information is relevant for the 
Administrator's use in making a decision about a chemical substance or 
mixture;
--The degree of clarity and completeness with which the data, 
assumptions, methods, quality assurance, and analyses employed to 
generate the information are documented;
--The extent to which the variability and uncertainty in the 
information, or in the procedures, measures, methods, protocols, 
methodologies, or models, are evaluated and characterized; and;
--The extent of independent verification or peer review of the 
information or of the procedures, measures, methods, protocols, 
methodologies or models.

    3. Conditions of use as defined in 15 U.S.C. 2602(4), means the 
circumstances, as determined by the Administrator, under which a 
chemical substance is intended, known, or reasonably foreseen to be 
manufactured, processed, distributed in commerce, used, or disposed of. 
This definition was not included in the proposed rule, but has been 
added for clarity. Additional discussion of conditions of use can be 
found in Unit B.
    4. Pathways. Pathways of exposure refers to the mode through which 
one is exposed to a chemical substance, including but not limited to: 
Food, water, soil, and air (Ref. 4). This definition is consistent with 
EPA's policies and practices, and did not change from the proposed 
rule.
    5. Potentially exposed or susceptible subpopulations. TSCA requires 
EPA to evaluate risk to ``potentially exposed or susceptible 
subpopulation[s]'' identified as relevant to the risk evaluation by the 
Administrator, under the conditions of use. 15 U.S.C. 2605(b)(4)(A). 
TSCA defines this as ``the term `potentially exposed or susceptible 
subpopulation' means a group of individuals within the general 
population identified by the EPA who, due to either greater 
susceptibility or greater exposure, may be at greater risk than the 
general population of adverse health effects from exposure to a 
chemical substance or mixture, such as infants, children, pregnant 
women, workers, or the elderly.'' 15 U.S.C. 2602(12). EPA proposed a 
definition to clarify how the Agency interprets this provision. 
Specifically, EPA proposed to substitute the phrase ``including but is 
not limited to'' for the statutory phrase ``such as,'' to clarify that 
the statutory list of potential subpopulations is not exclusive. EPA 
also proposed to include additional examples of subpopulations that 
have been previously considered. In response to comments, the final 
rule simply codifies the statutory definition without revision.
    EPA received a number of comments regarding this definition. Some 
stated that EPA was correct in expanding and clarifying the definition 
in the proposed rule, while others stated that EPA should use the 
statutory definition. Many comments that supported the proposed 
definition also identified other subpopulations that EPA should 
include. EPA's view of the interpretation of the statutory definition 
has not changed since proposal--EPA interprets the statutory definition 
broadly and believes it does not prevent EPA from including any 
subpopulation that may be at greater risk due to greater susceptibility 
or exposure, or from identifying additional subpopulations other than 
those listed in the statute, where warranted. The definition in the 
final rule uses the statutory definition because, due to EPA's broad 
interpretation, EPA does not think that it limits any consideration of 
a particular subpopulation. Also, regarding EPA's proposed inclusion of 
more examples than those provided by the statute (e.g., life-stage, 
age, gender, geography), and in reading public comments, which listed 
numerous other important subpopulations EPA should consider, it was 
clear that it would be difficult for the Agency to list all the 
potential subpopulations that the Agency might have reason to include 
in a risk evaluation. Codification of the statutory definition does not 
limit the subpopulations that may be evaluated and ensures there is no 
misconception that a partial list was intended as a deliberate 
exclusion of other subpopulations.
    6. Reasonably available information. TSCA section 26(k) (15 U.S.C. 
2625(k)) states that in carrying out risk evaluations, EPA shall 
consider information that is ``reasonably available,'' but the statute 
does not further define this phrase. EPA is defining ``reasonably 
available information'' to mean information that EPA possesses, or can 
reasonably obtain and synthesize for use in risk evaluations, 
considering the deadlines for completing the evaluation. However, there 
is a preference for reasonably available information that is consistent 
with the required quality standards. Information that meets the terms 
of the preceding sentence is reasonably available information whether 
or not it is claimed as confidential business information. This 
definition is slightly revised from the proposed definition.
    First, EPA deleted the word ``existing'' to address concerns that 
this would prevent the Agency from considering (or requiring) data 
generated in response to EPA data gathering, including testing, 
authorities. Several commenters encouraged EPA to take full advantage 
of its new information gathering authorities and not limit the basis of 
its decisions to ``existing'' information. EPA agrees that it makes 
sense to view information that can be obtained through testing as 
``reasonably available'' in some instances--especially information that 
can be obtained through short-term testing, where it can be obtained 
within the relevant statutory deadlines and the information would be of 
sufficient value to merit the testing. As discussed in a related 
rulemaking on prioritization under TSCA, EPA will seek to generally 
ensure that sufficient information to complete a risk evaluation exists 
and is available to the Agency prior to initiating the evaluation. The 
proposed definition was drafted to reflect that intention. However, EPA 
also recognizes that there may be circumstances where additional 
information may need to be developed within the time frames of the risk 
evaluation process. This may include information developed through the 
use of novel and advancing chemical assessment procedures, measures, 
methods, protocols, methodologies, or models (e.g., high-throughput 
chemical assessment techniques). While EPA disagrees that its original 
definition would have precluded the generation of additional data, to 
avoid any confusion, EPA has modified the definition to clarify the 
point. Note that EPA will, as appropriate, also require longer-term 
testing, and at times will need to do so to address data gaps. However, 
EPA does not think information that could be generated through such 
testing should be viewed as ``reasonably available''. EPA will tailor 
its information gathering efforts as appropriate.
    Second, EPA added a statement regarding CBI to clarify to the 
public that EPA does consider CBI under section 14 of TSCA to be 
``reasonably available,'' and will utilize it in risk evaluations where 
relevant.
    7. Routes. The final rule defines routes of exposure to mean the 
particular manner which a chemical substance may contact the body, 
including absorption via ingestion, inhalation, or dermally (Ref. 4). 
This definition is consistent with EPA's policies and practices and 
with the proposed definition.

[[Page 33733]]

    8. Sentinel exposure. The final rule defines sentinel exposure to 
mean the exposure to a single chemical substance that represents the 
plausible upper bound of exposure relative to all other exposures 
within a broad category of similar or related exposures. As mentioned 
in the proposed rule, this term previously had not been defined by the 
Agency. In light of the comments received, many of which requested 
revisions to the proposed definition, EPA believes it most appropriate 
to revise the definition in the proposed rule. The majority of comments 
explained that the concept of sentinel exposures is narrower than the 
definition EPA had proposed (``the exposure of greatest significance, 
which may be the plausible maximum exposure''); rather, as one comment 
explained, sentinel exposures are employed to represent broad 
categories of use so that the assessor does not have to go into each 
specific subcategory of use. While sentinel exposures do represent 
upper-bound exposures--which is part of what EPA proposed--it is the 
upper bound within those broad use categories. Under this approach, 
because the exposures are expected to be much greater than other 
sources or pathways, if the margin of exposure is at an acceptable 
level, there is no need to specifically evaluate the other individual 
exposure pathways in the category. A number of commenters also 
suggested that EPA adopt the approach to `sentinel exposure' used by 
the European Union's (EU) European Chemicals Agency (ECHA) 
Registration, Evaluation, Authorization, and Restriction of Chemicals 
(REACH) program and Health Canada (Ref. 6 and 7). The final definition, 
although not the same as the one used by ECHA and Health Canada, more 
closely tracks their approach. Specifically, the definition seeks to 
address situations including but not limited to: (1) The same chemical 
substance is added to a number of related products, and EPA is 
evaluating exposure to the chemical substance in these related products 
under the same exposure scenario (e.g., adults who could use these 
products for the same task). If EPA identifies and evaluates the 
product associated with the upper bound of exposure from use of these 
products, then EPA could reach risk conclusions for the chemical 
substance in the entire category of these products, because the range 
of potential exposures is no greater than the magnitude of the exposure 
to the chemical substance in the upper-bound product. (2) A number of 
different workers are exposed to the same chemical substance. If EPA 
identifies or evaluates the worker whose exposure represents the upper 
bound of exposure, EPA would have confidence that the other workers 
exposed would be less exposed than the worker with the upper bound or 
``sentinel'' exposure.
    In the proposed rule, EPA used the phrase ``maximum exposure'' in 
defining sentinel exposure. This phrase has been changed to ``upper 
bound of exposure'' in the final rule. This change was a result of 
public comment that suggested that the term ``maximum'' could indicate 
that EPA intended to use only the 99.99th percentile exposure. This was 
not EPA's intent, and so EPA has substituted the phrase ``upper-bound 
of exposure,'' which is consistent with EPA's existing practice, and 
allows EPA the flexibility to consider the available data and its 
quality in determining the appropriate exposure scenario (e.g., 
sentinel exposure scenarios).
    9. Uncertainty and variability. The statute requires EPA to 
consider ``the extent to which the variability and uncertainty . . . 
are evaluated and characterized.'' 15 U.S.C. 2625(h). EPA proposed 
definitions for both ``variability'' and ``uncertainty'' based on 
existing Agency guidance (Framework for Human Health Risk Assessment). 
The final rule adopts the proposed definition of ``uncertainty'' with 
minor modification. EPA added the phrase ``the real world'' to exactly 
reflect the definition in Agency guidance. In the final rule, 
uncertainty means the imperfect knowledge of the real world or lack of 
precise knowledge of the real world either for specific values of 
interest or in the description of the system (Ref. 8). The final rule 
adopts the proposed definition of ``variability'' without modification. 
The regulation thus states: ``Variability'' means the inherent natural 
variation, diversity, and heterogeneity across time and/or space or 
among individuals within a population (Ref. 8). Both definitions are 
consistent with EPA's policies and practices.
    10. Weight of the scientific evidence. The Agency is required by 
the statute to use a weight of scientific evidence approach in a risk 
evaluation and the Agency is codifying a definition of this term in 
this final rule. In responding to public comment, EPA notes that 
inclusion of the definition will provide the much requested 
transparency to the public regarding the processes for how the Agency 
reviews scientific information used in risk evaluations without 
stifling scientific advances. In the preamble to the proposed rule, EPA 
provided an extensive discussion of how the weight of the scientific 
evidence is applied by EPA and the National Toxicology Program of the 
National Institutes of Environmental Health. This discussion formed 
part of the basis for the definition EPA is promulgating in this final 
rule.
    The application of weight of the scientific evidence has generated 
much discussion in the scientific community, and EPA agrees with the 
National Academies who stated ``because scientific evidence use in 
weight of the scientific evidence (WoSE) evaluations varies greatly 
among chemical and other hazardous agents in type, quantity and 
quality, it is not possible to describe the WoSE evaluation in other 
than relative general terms'' (Ref. 9). Application of weight of the 
scientific evidence analysis is an integrative and interpretive 
process. It is more than a simply tallying of the number of positive 
and negative studies. It also is applicable to both human health and 
ecological risk evaluations.
    There are certain principles of weight of the scientific evidence 
that are universal, including foundational considerations, such as 
objectivity and transparency, and the general process. This process 
starts with assembling the relevant information, evaluating the 
information for quality and relevance, and synthesizing and integrating 
the different lines of evidence to support conclusions (Ref. 10). Given 
these overarching and inclusive principles, EPA does not think that 
providing a general definition restricts flexibility or scientific 
advancement. For the purposes of this rule the definition EPA is 
adopting states: ``Weight of the scientific evidence means a systematic 
review method, applied in a manner suited to the nature of the evidence 
or decision, that uses a pre-established protocol to comprehensively, 
objectively, transparently, and consistently identify and evaluate each 
stream of evidence, including strengths, limitations, and relevance of 
each study and to integrate evidence as necessary and appropriate based 
upon strengths, limitations, and relevance.'' This definition was 
suggested by a few public commenters, it is consistent with practices 
under TSCA before it was amended, and was generally outlined in the 
lengthy discussion in the proposal. The bulk of the definition, aside 
from the phrase ``applied manner suited to the nature of the evidence 
or decision'' clarification, is taken directly from TSCA's legislative 
history. See Congressional Record at S3519, June 7, 2016. The 
additional phrase was added to be consistent with the concept (also 
discussed in the proposal) that the components of its risk evaluations 
will

[[Page 33734]]

be ``fit-for-purpose.'' As explained in the proposed rule at 82 FR 
7566, all conditions of use will not warrant the same level of 
evaluation, and EPA expects that it may, in some cases, be able to 
reach conclusions without extensive or quantitative evaluations of 
risk. The addition of this phrase to the definition is intended to 
clarify that different weight of the scientific evidence review methods 
may be appropriate for different information, types of evaluations, or 
decisions. Specifically, fit-for-purpose means that while EPA will 
always apply the principles contained in the definition, the depth or 
extent of the analysis will be commensurate with the nature and 
significance of the decision.
    11. Systematic Review. EPA requested comment on the need for 
regulatory text prescribing a specific systematic review approach for 
hazard identification, including the appropriateness of elements that 
might be included or concerns about codifying an approach. Commenters 
both supported and opposed the inclusion of systematic review in the 
rule text. Those opposing the codification of systematic review argued 
that EPA should retain flexibility and the ability to change the 
process as improved methods for systematic review are developed. Some 
commenters did encourage a description of the intended approach in the 
preamble, but suggested that EPA reserve the specific process for 
guidance. Those in support of codifying a description of systematic 
review in the rule text stated that inclusion would increase 
transparency and would provide the public with an indication of how the 
statutory requirement of weight of the scientific evidence, 
requirements of sections 6 and 26, and an integral component of 
systematic review, will be applied.
    EPA intends to use the systematic review approach, described in the 
proposed rule, but is not codifying a definition in the regulatory 
text. To be clear, although EPA asked for comment on the need for 
regulatory text for systematic review on hazard identification 
specifically, EPA will not limit the use of this approach solely to the 
hazard assessment, but will use it throughout the risk evaluation 
process. The inclusion of a description of systematic review in the 
preamble is the most appropriate approach in light of public comment 
and the requirements of the statute. First, systematic review is not 
required under the statute, only a weight of the scientific evidence 
analysis. The definition the Agency is adopting for ``weight of the 
scientific evidence'' uses the phrase ``systematic review,'' which 
addresses to some extent the commenters who favored including the 
concept in this regulation.
    EPA sees weight of the scientific evidence approach as an 
interrelated part of systematic review, and further believes that 
integrating systematic review into the TSCA risk evaluations is 
critical to meet the statutory requirements of TSCA. Although, as EPA 
discusses elsewhere in this preamble, there are universal components of 
systematic review that EPA intends to apply in conducting risk 
evaluations, this is one area where EPA concluded it would be premature 
to codify specific methods and criteria that may change as the Agency 
gains more experience conducting TSCA risk evaluations. As requested by 
commenters, EPA does believe the addition of discussion of the 
systematic review approach the Agency intends on utilizing is necessary 
for transparency, and so provides the description herein. Section 26(l) 
also requires EPA to develop and revise Agency guidance. The Agency 
intends to provide further details on systematic review and weight of 
scientific evidence approaches under TSCA in future guidance documents.
    As defined by the Institute of Medicine (Ref. 11) systematic review 
``is a scientific investigation that focuses on a specific question and 
uses explicit, pre-specified scientific methods to identify, select, 
assess, and summarize the findings of similar but separate studies. The 
goal of systematic review methods is to ensure that the review is 
complete, unbiased, reproducible, and transparent'' (Ref. 11).
    The principles of systematic review have been well developed in the 
context of evidence-based medicine (e.g., evaluating efficacy of 
medical interventions tested in multiple clinical trials) (Ref. 12) and 
are being adapted for use across a more diverse array of systematic 
review questions, through the use of a variety of computational tools. 
For instance, the National Academies' National Research Council (NRC) 
has encouraged EPA to move towards systematic review processes to 
enhance the transparency of scientific literature review that support 
chemical-specific risk assessments to inform regulatory decision making 
(Ref. 13). Key elements of systematic review include:

--A clearly stated set of objectives (defining the question);
--Developing a protocol which describes the specific criteria and 
approaches that will be used throughout the process;
--Applying the search strategy criteria in a literature search;
--Selecting the relevant papers using predefined criteria;
--Assessing the quality of the studies using predefined criteria;
--Analyzing and synthesizing the data using the predefined methodology;
--Interpreting the results and presenting a summary of findings (Ref. 
14)

    12. Sufficiency of information. EPA did not propose to codify this 
phrase, but discussed it in the context of having ``enough'' 
information to conduct a risk evaluation within the statutory 
timeframe. However, EPA also specifically requested comment on whether 
to define sufficiency of information. Commenters who opposed codifying 
a definition stated that the phrase was ``vague'' and could have a 
number of definitions and that the information needs for chemical risk 
evaluations can vary significantly, so not one definition would be 
appropriate. Commenters who supported codifying a definition of this 
phrase stated that, specifically for risk evaluation conducted and 
submitted by third parties, knowledge of what constitutes sufficient 
information is necessary. Consistent with the proposed rule, the final 
rule does not codify this term because EPA agrees that the information 
required for chemical risk evaluations can be highly variable, and that 
given the case-by-case nature of the hazard and exposure scenarios, it 
is difficult to have an overarching definition of ``sufficient 
information'' applicable to all evaluations. EPA does not believe that 
the definitions offered by the commenters would provide any greater 
clarity that would effectively inform third party risk evaluations and 
expansion of this concept is more appropriate for the statutorily 
required guidance documents.
    13. Unreasonable risk. In the proposed rule, EPA said that the 
Agency did not think it was appropriate to define ``unreasonable risk'' 
because each risk evaluation will be unique. For example, defining 
specific risk measures for use in all risk evaluations would be 
inappropriate to capture the broad set of health and environmental risk 
measures and information that might be relevant to chemical substances. 
In the preamble to the proposed rule, EPA did discuss some of the 
considerations the Agency will use in making a risk determination. The 
public overwhelmingly agreed with the proposed approach. EPA did take 
public comment on this approach and the public agreed that a definition 
was not appropriate, but appreciated EPA's approach to including 
considerations.
    For the final rule. the Agency will be taking the same approach, 
and has

[[Page 33735]]

identified, a revised list of some of the considerations that the 
Agency will use in making a risk determination. This is not intended as 
an exhaustive list, but merely identifies some of the considerations 
that are likely to be among the most commonly used. However, the list 
of considerations has changed slightly in response to public comment. 
In the proposed rule preamble a few considerations were too specific 
and were not expected to be widely applicable to TSCA risk evaluations. 
For example, the proposed rule included the specific mention of margin 
of exposure (MOE), which is just one approach for risk 
characterization. EPA acknowledges that MOE is just one of several 
approaches to risk characterization, and agrees that it does not make 
sense to single out this one particular approach. There will be risk 
scenarios where one approach may be better than another and, as 
commenters correctly pointed out, the science of risk characterization 
is still evolving, particularly for non-cancer hazards. The proposed 
preamble had also included the consideration of cumulative exposure in 
making a risk determination. A number of commenters pointed out, this 
is not a requirement under the statute; EPA agrees that this may not be 
widely applicable to many TSCA risk assessments, and so EPA has not 
included it in the list below. Additionally, commenters correctly 
pointed out that EPA did not mention environmental risks in the 
proposed definition. Considerations of environmental hazards and 
exposures have been added.
    To account for the number of different risk characterization 
approaches and for changing science, EPA will not include any specific 
definition in this final rule. To make a risk determination, EPA may 
weigh a variety of factors in determining unreasonable risk. The 
Administrator will consider relevant factors including, but not limited 
to: The effects of the chemical substance on health and human exposure 
to such substance under the conditions of use (including cancer and 
non-cancer risks); the effects of the chemical substance on the 
environment and environmental exposure under the conditions of use; the 
population exposed (including any susceptible populations), the 
severity of hazard (the nature of the hazard, the irreversibility of 
hazard), and uncertainties.

E. Timing of Risk Evaluations

    A risk evaluation is initiated upon the final designation of a high 
priority substance at the completion of the prioritization process or 
through the completed manufacturer request process. A risk evaluation 
is complete upon the publication of the final risk evaluation, which 
includes the final risk determination for all the conditions of use 
identified in the Scope document. As indicated, the statute requires 
EPA to complete risk evaluations within three years, with the 
possibility of a single six-month extension. This rule adopts these 
timeframes without modification or elaboration.

F. Chemical Substances for Risk Evaluation

    As identified previously, chemical substances that will undergo 
risk evaluation can be put into three groups: (1) The first ten 
chemical substances the Agency is required to identify within the first 
180 calendar days of enacting the amendments to TSCA (15 U.S.C. 
2605(b)(2)); (2) the chemical substances determined as High-Priority 
Substances through the prioritization process proposed in a separate 
rulemaking; and (3) chemical substances requested by manufacturers, 
when the requests meet the criteria for EPA to conduct an Agency risk 
evaluation.
    Public comment requested that EPA be explicit about what 
constitutes a chemical substance under TSCA. The statute defines a 
chemical substance to mean any organic or inorganic substance of a 
particular molecular identity, including: (1) Any combination of such 
substances occurring in whole or in part as a result of a chemical 
reaction or occurring nature, and (2) and element or uncombined 
radical. Chemical substances do not include: (1) Any mixture, (2) any 
pesticide (as defined in the Federal Insecticide, Fungicide, and 
Rodenticide Act) when manufactured, processed, or distributed in 
commerce for use as a pesticide, (3) tobacco or any tobacco product, 
(4) any source material, special nuclear material, or byproduct 
material (as such terms are defined in the Atomic Energy Act of 1954 
and regulations issued under such Act), (5) any article the sale of 
which is subsequent to the tax imposed by section 4181 of the Internal 
Revenue Code of 1954 (determined without regard to any exemptions from 
such tax provided by section 4182 or 4221 or any other provision of 
such Code), and (6) any food, food additive, drug, cosmetic, or device 
(as such terms are defined in section 201 of the Federal Food, Drug, 
and Cosmetic Act) when manufactured, processed, or distributed in 
commerce for use as a food, food additive, drug, cosmetic, or device. 
15 U.S.C. 2602(2)(B). The list constitutes what is commonly referred to 
as ``non-TSCA uses.'' It may be appropriate for EPA to consider 
potential risk from non-TSCA uses (as identified above) in evaluating 
whether a chemical substance presents an unreasonable risk, although 
these uses would not be within the scope of the risk evaluation. EPA 
would explain the basis for such consideration in any risk evaluation. 
EPA may not in a risk management rule under section 6(a) regulate non-
TSCA uses. TSCA Sec.  6(a) generally provides that if EPA determines 
that the manufacture, processing, distribution in commerce, use, or 
disposal of a chemical substance or mixture, or that any combination of 
such activities, presents an unreasonable risk of injury to health or 
the environment, the Agency must apply certain regulatory requirements 
to the extent necessary so that the chemical substance or mixture no 
longer presents such risk. The potential risks of non-TSCA uses may 
help inform the Agency's risk determination for the exposures from uses 
that are covered under TSCA (e.g., as background exposures that would 
be accounted for, should EPA decide to evaluate aggregate exposures).

G. Process and Criteria for Manufacturer Requested Risk Evaluations.

    TSCA allows a manufacturer or group of manufacturers to request 
that the Agency conduct a risk evaluation of a chemical substance (or 
group of substances) that they manufacture. The statute further directs 
EPA to establish the ``form . . . manner and . . . criteria'' for such 
requests as part of this rule.
    1. Scope of request. In the proposed rule, EPA required the 
manufacturers submitting the request to include all information 
necessary to conduct a risk evaluation on all conditions of use. EPA 
received numerous public comments on this provision. EPA did receive 
comments that supported the proposed approach, indicating that the 
approach was consistent with EPA's own process for evaluating high 
priority chemicals, and because the chemicals evaluated as the result 
of a manufacturer request will have not gone through the Prioritization 
process, where the bulk of information may be gathered, it was 
appropriate to have manufacturers submit all information necessary to 
conduct a risk evaluation for all conditions of use. Those opposed to 
the proposed approach stated that manufacturers are not always privy to 
every downstream use, and therefore would find it very difficult to 
obtain all the required information. Commenters also expressed concern 
that the bar set in the proposed rule overall was too high and

[[Page 33736]]

would make it extremely difficult for manufacturers to submit a 
compliant request, and that the extensive requirements EPA had proposed 
could create a disincentive to submit requests for risk evaluation.
    EPA agrees with many of these concerns in opposition to the 
proposed approach. EPA believes that Congress intended for EPA to 
establish a process under which the 25%-50% target would most likely be 
met. The law instructs EPA to ``ensure'' that that target is met. 
Section 6(b)(4)(E)(i). While this is conditioned on EPA's receipt of a 
sufficient number of compliant requests, EPA believes it signals an 
intent that the criteria for requests make it reasonably likely that 
the target will be met. Legislative history supports this reading. See 
S3516 (June 7, 2016) (``The Administrator should set up a system to 
ensure that those percentages are met and not exceeded in each fiscal 
year.'')
    Upon consideration of these comments, among others, EPA is 
modifying its proposal in several ways. First, the final rule allows 
manufacturers to submit requests for risk evaluation on only the 
conditions of use of the chemical substances that are of interest to 
the manufacturer.
    Although manufacturers may request that EPA conduct a risk 
evaluation based on a subset of the conditions of use, EPA intends to 
conduct the risk evaluation in the same manner as any other risk 
evaluation conducted under section 6(b)(4)(A). This is clear from 
subsections (A) and (C), and from section 6(b)(4)(E)(ii), which 
expressly directs that the Administrator shall not expedite or 
otherwise provide special treatment to manufacturer-requested risk 
evaluations. As such, EPA intends to conduct a full risk evaluation 
that encompasses both the conditions of use that formed the basis for 
the manufacturer request, and any additional conditions of use that EPA 
identifies, just as EPA would if EPA had determined the chemical to be 
high priority. However, rather than require the manufacturer to 
identify any additional conditions of use that EPA will evaluate, EPA 
will determine the additional conditions of use during the process of 
determining whether to grant or deny the manufacturer request. From 
receipt of a compliant request to initiation of a risk evaluation EPA 
anticipates 195 days. This includes: (1) Public notification of request 
within 15 days of receipt; (2) Within 60 days after receipt of the 
request, EPA will publish the request in the Federal Register; (3) EPA 
will open a docket to facilitate a no less than 45-day public comment 
period; (4) Within 60 days of the end of the comment period EPA will 
issue the decision to grant or deny the request; (5) Upon a decision to 
grant a request, the requester has 30 days to withdraw the request or 
EPA will move to initiate the risk evaluation.
    Upon receipt of a request, EPA will evaluate whether the 
circumstances of manufacture, processing, distribution in commerce, 
use, and/or disposal identified by the submitter constitute conditions 
of use that warrant risk evaluation and whether additional conditions 
of use need to be included in the risk evaluation. EPA will apply the 
same criteria in the same manner outlined earlier in this preamble in 
making these evaluations.
    EPA must complete the full risk evaluation that encompasses both 
the conditions of use that formed the basis for the manufacturer 
request, and any additional conditions of use that the Administrator 
determines under section 15 U.S.C. 2605(b)(4)(A), within the statutory 
three-year deadline. However, as discussed elsewhere in this preamble, 
EPA may make an early risk determination on any condition of use 
included in the Agency's scope, after peer review of the risk 
evaluation for that condition of use. Thus, since manufacturers are 
required to submit all of the information necessary to complete risk 
evaluation for the identified conditions of use, EPA expects these 
conditions of use may be good candidates for an early determination.
    2. Information that must be submitted as part of request. 
Consistent with the proposal, a request must include the chemical 
identity--all known names, CAS number, and molecular structure. 
Manufacturers may also submit requests for categories of chemical 
substances, and such requests must include an explanation of why the 
category is appropriate under 15 U.S.C. 2625(c). EPA will grant such 
request only upon determining that the requested category is 
appropriate for risk evaluation. As described above, manufacturers may 
now request a risk evaluation based on a subset of conditions of use. 
The manufacturer's request must include all of the information 
necessary for EPA to conduct the evaluation for the requested 
conditions of use, consistent with the requirements in sections 15 
U.S.C. 2605(b)(4)(A), and 15 U.S.C. 2625(h). This includes all of the 
necessary information, as relevant to the requested conditions of use, 
on the chemical substance's hazard and exposure potential; the chemical 
substance's persistence and bioaccumulation; any relevant potentially 
exposed or susceptible subpopulation; whether there is any storage of 
the chemical substance near significant sources of drinking water, 
including the storage facility location and nearby drinking source; the 
chemical substance's production volume or significant changes in 
production volume; and any other information relevant to the risks 
potentially presented by the chemical substance. The requesting 
manufacturer does not need to supply a copy of the information if it is 
publicly available, but must list all references. These are the same 
requirements EPA listed in the proposed rule; however, the scope of the 
request may be narrower, specifically regarding the conditions of use 
requested. Some comments argued that it would be exceedingly difficult 
to obtain information for uses that the requesting manufacturer may 
have no knowledge of. EPA agrees with that, and that is a large part of 
the motivation behind EPA's decision to allow manufacturers to request 
risk evaluations on limited conditions of use. However, for those 
conditions of use requested, the manufacturer must provide all the 
information EPA needs for risk evaluation.
    Any information submitted by a manufacturer must be consistent with 
the scientific standards in 15 U.S.C. 2625(h). Although the judgement 
of consistency is ultimately EPA's, holding the requester to the 
statutory standard helps to ensure that if EPA grants the request, the 
Agency can effectively utilize the information provided. Additionally, 
any information submitted that is claimed as CBI must be accompanied by 
a redacted version of the information, including as necessary an 
accession number and a structurally descriptive generic name. 
Instructions for submitting CBI are also included in this rule. 
Consistent with EPA's general interpretation of section 14, the rule 
requires upfront substantiation of non-exempt CBI claims.
    The final rule also includes a number of other revisions to the 
information that must be submitted for the request to be considered. In 
the proposed rule, EPA required manufacturers to submit in the request 
any risk assessment or evaluation that they might possess. This was 
added to the proposed rule to provide the Agency with additional 
information, specifically, as it relates to the hazard assessment. The 
Agency's intent was to use this as purely another source of 
information, not base any decision solely on the information in this 
document. Commenters argued that these risk assessments or evaluations 
may have been conducted under a different statute or for a particular 
purpose, and therefore may not be

[[Page 33737]]

useful or appropriate under TSCA. Additionally, commenters stated that 
a risk evaluation may have been conducted in response to litigation and 
therefore would be protected under attorney client privilege. In 
response to public comments, EPA is removing the requirement that the 
manufacturer must commit to providing EPA existing risk assessments on 
the chemical. EPA believes that all relevant risk assessments would be 
required to be provided pursuant to TSCA section 8(e), and/or would be 
submitted in response to the regulatory provision that requires that 
the requesters provide any information relevant to the potential risks 
of the chemical substance under the circumstances identified in the 
request.
    Many commenters also requested that EPA rephrase the certification 
statement. Commenters stated that the content of the certification was 
overly aggressive and unnecessary given the enforcement provision at 
the beginning of the regulation and the enforcement that applies to all 
of TSCA.
    3. Process for evaluating requests. Upon receipt of the request, 
EPA will verify that the request appears to be valid, i.e., that 
information has been submitted that is consistent with the regulatory 
requirements. Within 15 business days of receiving a facially valid 
request, EPA will publish a public notice of the receipt, which will 
include the manufacturer request. This notice is intended to give the 
public early notice of the chemical substance that may be under 
evaluation from a manufacturer request. Due to the 15 day turn around 
on this public notice this will not be a Federal Register Notice, but 
an announcement on the Agency's Web site and/or an email announcement. 
Between receipt of the request and the subsequent end of public comment 
period (discussed in this next part), EPA will work to identify any 
additional conditions of use, if any, of the chemical requested. Within 
60 days from receipt, EPA will submit for publication an announcement 
of the receipt of the request in the Federal Register, open a docket 
for the request, make available the information that has been submitted 
(taking into account any valid CBI claims), and provide no less than a 
45-day comment period. This notice will include the manufacturer 
request and EPA's proposed determinations as to whether the activities 
identified in the request are conditions of use that warrant risk 
evaluation, and whether there are additional conditions of use that 
need to be included in the risk evaluation. This public comment period 
will allow the public to comment on EPA's proposed determinations and 
to identify and/or submit any reasonably available information 
regarding hazard, exposure, potentially exposed populations and 
subpopulations, and conditions of use that may help inform a risk 
evaluation. The requesting manufacturer may also submit any additional 
material during this time.
    Chemical substances that EPA has prioritized through the 
prioritization process (the subject of separate rulemaking (EPA-HQ-
OPPT-2016-0636)), are subject to two separate public comment periods 
prior to the completion of the prioritization process. These comment 
periods are designed to ensure that EPA has the necessary information 
to evaluate the chemical substances, including, in particular, 
information on the relevant conditions of use. EPA is adopting the 
similar structure described here for manufacturer requests, under which 
EPA will solicit input from the public prior to the decision on whether 
to grant the request, as part of the method by which EPA will identify 
and gather information on the additional conditions of use to be 
addressed in the final risk evaluation. Since manufacturers are 
required to submit all the information necessary to complete risk 
evaluation on the identified conditions of use, EPA generally expects 
that the submitted information would include reasonably complete 
toxicity information on the chemical, even though it would likely not 
include exposure information relevant to the other conditions of use. 
While this pre-risk evaluation process for manufacturer request differs 
from the process of high-priority substances and compresses the period 
in which EPA will identify conditions of use and supporting 
information, EPA believes that some differences are necessary in order 
to effectuate Congress' intent to create a workable process for 
manufacturer requests that is reasonably likely to hit the numerical 
target in the statute. Through this mechanism, EPA expects that in many 
cases, the available information will be comparable to what EPA will 
identify or generate through the measures identified in the 
prioritization framework rule. During the public comment period 
associated with each manufacturer request, EPA encourages public 
commenters to identify additional information to inform a risk 
evaluation that was not in the manufacturer request, including any 
additional conditions of use.
    At any time prior to the end of the comment period, the 
manufacturer may supplement the original request with new information 
they receive or obtain. At any point prior to the completion of a risk 
evaluation conducted on a chemical substance at the request of a 
manufacturer(s), manufacturer(s) are required to supplement the 
original request upon receipt of information that meets the criteria in 
15 U.S.C. 2607(e) and 40 CFR 702.37, or other information that has the 
potential to change EPA's risk evaluation for the requested conditions 
of use.
    Within 60 days after the end of the comment period, EPA will review 
the request along with any additional information received during the 
comment period to determine whether the request meets the regulatory 
criteria and will notify the manufacturer(s) accordingly. If EPA 
determines that the request is compliant (i.e., that the activities for 
which risk evaluation is requested constitute ``conditions of use'' as 
EPA interprets the term, and are conditions of use that EPA concludes 
warrant inclusion in the scope of a risk evaluation for the chemical, 
and that EPA has the required information necessary for conducting a 
risk evaluation on the condition(s) of use requested), EPA will grant 
the request. Otherwise, EPA will deny the request. Requesters may 
resubmit any denied request. Within 30 days of the notice that EPA will 
grant the request, the requestor may withdraw the request for any other 
reason after the Agency has notified the requester of the decision to 
grant or deny. For EPA to proceed with a risk evaluation on the 
chemical requested, it would have to go through the Prioritization 
process. The process for conducting the risk evaluation will follow the 
regulatory requirements applicable to high-priority chemical risk 
evaluations and will not be expedited or otherwise afforded special 
treatment. EPA will initiate the risk evaluation consistent with TSCA 
section 6(b)(4)(E)(i) upon payment of required fees requirements as 
established in the Fees Rule. EPA is not addressing in this rulemaking 
the fee amount for manufacturer requested evaluations. The fee amount 
will be addressed in a separate rulemaking process.
    Consistent with TSCA section 6(b)(4)(E)(iii), EPA will give 
preference to requests where there is evidence that restrictions 
imposed by one or more States have the potential to have a significant 
impact on interstate commerce or health or the environment, and is 
therefore proposing to allow (but not require) manufacturers to include 
any evidence to support such a finding. Following this required initial 
preference, EPA will give further preference to requests in the order 
in which a request is received. This last

[[Page 33738]]

provision regarding preference is a change from the proposed rule, 
where EPA indicated that preference would be given to chemicals where 
EPA determined that there were relatively high estimates of hazard and/
or exposure for the chemical substance. EPA received a number of 
comments arguing that this was not an appropriate way to order 
chemicals to be evaluated. First, comments asked for a definition of 
``high estimates of hazard or exposure.'' Other commenters suggested 
that manufacturers may submit a request for a low hazard or exposure 
chemical to get the EPA determination of no unreasonable risk. There 
were also a few comments that stated that the proposed preference 
scheme was appropriate in addressing the worst chemicals first. While 
EPA agrees that this is the best way to approach the identification of 
high priority substances, EPA does not believe this is necessarily the 
best approach for selecting among manufacturer-requested evaluations. 
EPA believes, on reflection, that Congress intentionally established 
the process for industry requests, to operate outside of the 
prioritization process, under which lower risk chemicals might be 
identified for risk evaluation. Therefore, EPA has dropped this 
proposed preference. EPA also acknowledges it is possible that 
manufacturers could request an evaluation seeking to get an Agency 
determination of no unreasonable risk.

H. Interagency Collaboration

    In the proposed rule, EPA committed to ensuring there will be 
interagency engagement and dialogue throughout its risk evaluation 
process; however, EPA chose not limit the potential interagency 
collaboration by proposing to codify any particular process. EPA 
requested specific public comment on whether codifying this 
collaboration at a specific point regulation was appropriate. 
Overwhelmingly, commenters were supportive of collaboration with other 
agencies, and some comments encouraged additional collaboration with 
state and local agencies, global partners, and tribes. There were mixed 
comments regarding the codification of interagency collaboration at a 
particular point in the risk evaluation process. Those in support of 
the collaboration stated that other agencies, such as the Occupational 
Safety and Health Administration (OSHA) and the National Institute of 
Occupational Safety and Health (NIOSH), may have additional information 
on worker exposure that will undoubtedly be useful for EPA in 
conducting the risk evaluation. Those opposing the codification argued 
that this would be overly bureaucratic and a waste of resources, as not 
all agencies would have an interest/information on every chemical so 
there would not always be the necessity to consult with them.
    EPA has codified collaboration to give the public confidence that 
EPA will work with other agencies to gain appropriate information on 
chemical substances. As stated a number of times in this preamble, EPA 
is committed to transparency and communication with the public. 
Codification of interagency collaboration is just one more example of 
this commitment. Through this interagency process, EPA expects to gain 
additional information into uses and exposure scenarios, with which 
other agencies may be more familiar. Additionally, during interagency 
meetings (under the Office of Management and Budget process of 
reviewing the proposed rule), other federal agencies expressed 
significant interest in early and frequent collaboration. Agencies such 
as NIOSH and OSHA have resources available and information for 
assessing exposure to workers that EPA may not have. Communication with 
the Small Business Administration (SBA) Office of Advocacy was 
requested by a number of commenters. Collaboration with Consumer 
Product Safety Commission (CPSC), which some commenters argued will be 
necessary, was requested as EPA evaluates chemicals commonly found in 
consumer products. There are a number of other agencies that have 
information and expertise that will undoubtedly be useful to the EPA, 
and codified collaboration, along with mechanisms already in place, 
further guarantees that this information will be utilized.
    By mandating consultation at any particular stage, EPA does not 
intend to imply that collaboration with agencies will solely occur at 
this step of the process, but including this collaboration upon 
initiation gives other agencies sufficient time to work with the EPA to 
identify any information that will be useful for EPA risk evaluation 
(e.g., existing regulations or mission critical uses) of the chemical 
substance. EPA anticipates that this collaboration would include 
agencies that may also regulate the chemical substance or the 
environment in which the chemical substance may be present, as well as 
agencies that may have critical operations that require the chemical 
being evaluated, or may otherwise be affected by regulation of the 
chemical substance. EPA will also consult with the SBA Office of 
Advocacy and other federal agencies, as appropriate, to help facilitate 
outreach to the small business sector.
    This provision also is not intended to suggest that EPA will not 
collaborate with federal agencies prior to the initiation of the risk 
evaluation. EPA has a number of existing mechanisms already in place to 
facilitate collaboration between EPA's federal partners and will 
continue to utilize them. Collaboration with other agencies is an 
important step in identifying chemicals prior to prioritization, as 
well as during the risk management phase, if a chemical use is 
determined to present an unreasonable risk.
    As requested in the comments, EPA also plans to engage with state 
and local agencies where they may have information to inform risk 
evaluations. Similarly, EPA looks to increase collaboration with 
tribes, as they can be impacted by chemical substances differently due 
to unique traditional activities and lifestyles, as discussed in 
comments.

H. Risk Evaluation Requirements

    1. Considerations. This subpart identifies and discusses what EPA 
will consider in conducting a risk evaluation. The first subpart 
identifies the necessary components of the risk evaluation process--a 
scope, which will include a Conceptual Model and Analysis Plan, a 
hazard assessment, an exposure assessment, a risk characterization, and 
a risk determination.
    a. Agency guidance. EPA has a number of existing guidance documents 
that inform Agency risk assessment. EPA has been using risk assessments 
as a tool to characterize the nature and magnitude of health risks to 
humans and ecological receptors from chemical contaminants and other 
stressors that may be present in the environment since its inception. 
Over the years, EPA has worked with the scientific community and other 
stakeholders to develop a variety of guidance, guidelines, methods and 
models for use in conducting different kinds of assessments. A 
compendium of existing Agency guidance related to risk assessments is 
maintained on EPA's Web site (Ref. 15). Additionally, on EPA's Web site 
is a compendium of guidance, databases and models used for assessing 
pesticide risks (Ref. 16) and information about available predictive 
models and tools for assessing chemicals under TSCA (Ref. 17). Each of 
these Web sites identify and link to a number of written guidance 
documents, tools and models.
    In the proposed rule, EPA made it clear that the Agency would be 
taking

[[Page 33739]]

advantage of existing guidance, tools and models that are relevant and 
available for use in conducting a risk evaluation under this program. 
Since each risk evaluation is based on the specific circumstances 
surrounding the chemical being assessed, EPA did not propose to mandate 
the use of any specific guidance, method or model, to ensure that there 
is flexibility. EPA asked for comments about this approach.
    The majority of the commenters did not think the Agency should 
mandate the use of or otherwise codify a list of guidance documents. 
Many public comments mentioned that many of the guidance documents were 
potentially outdated and were in need of updates. These commenters 
asserted that codifying these outdated documents would not be 
appropriate, nor accurately indicate to the public how risk evaluations 
will be conducted. Additionally, many commenters pointed out the 
provision in section 26(l) of TSCA that requires EPA to develop and to 
regularly review and update, the necessary policies, procedures, and 
guidance. This cuts against mandating use of particular guidance 
documents in regulation. Other commenters expressed concern that 
existing guidance did not take into account new science requirements in 
TSCA. By contrast, some expressed the view that the list should be 
codified, as it would result in added transparency to the process.
    EPA is not codifying a list of guidance (with the exception of the 
Metals Framework as mandated by TSCA), but states in the regulation 
that guidance may be used if it constitutes the best available science, 
and consistent with the weight of the scientific evidence. This 
approach is consistent with the proposed rule, and in line with the 
majority of the comments received on this subject. Rather than starting 
anew, EPA intends to take advantage of existing guidance, tools and 
models that are relevant and available for use in conducting a risk 
evaluation under this program. EPA added a new clause regarding the use 
of best available science and weight of the scientific evidence to the 
regulation; this addition of the clause regarding the use of best 
available science and weight of the scientific evidence was done to 
ensure that while the documents may have been developed under another 
statute, EPA will take care to ensure their use would be compliant with 
the various requirements of section 26 of TSCA. While EPA does think 
many of the current guidance documents can be utilized effectively 
under the statute, the Agency agrees with many of the comments that it 
will be necessary to modify some documents to further adhere to the 
amendments in the statute, as well as to reflect changing science and 
technology. Additionally, section 26(l) requires the development of any 
policies, procedures, and guidance that may be necessary to carry out 
the amendments of the law, and to routinely review and revise them as 
necessary to reflect scientific developments. Codifying documents that 
may be changed, while not codifying others that have yet to be 
developed, could potentially lead to long processes to change the rule 
language.
    The scope of each risk evaluation will identify those guidance 
documents that the Agency expects to utilize to inform the risk 
evaluation. EPA will use the guidance only to the degree that it 
represents the best available science appropriate for the particular 
risk evaluation. EPA recognizes that some guidance may be outdated and 
may rely on defaults where no data exists currently to replace those 
defaults.
    b. Categories of chemical substances. TSCA provides EPA with 
authority to take action on categories of chemical substances: Groups 
of chemical substances which are, for example, similar in molecular 
structure, in physical, chemical, or biological properties, in use, or 
in mode of entrance into the human body or into the environment. 
Although the rule most often references ``chemical substances,'' EPA 
includes a clear statement in the final regulation that nothing in the 
rule shall be construed as a limitation on EPA's authority to take 
action with respect to categories of chemical substances, and that, 
where appropriate, EPA can evaluate categories of chemical substances. 
This is the same provision that EPA included in the proposal, but EPA 
has removed the statement regarding the Agency's consideration of 
hazards and exposures associated with the category of chemicals, and 
the populations likely exposed. EPA believed that this was duplicative, 
because EPA is required to treat categories of chemicals in the same 
manner as individual chemical substances.
    c. Science requirements. EPA has incorporated into the regulatory 
text the statutory requirements regarding best available science and 
weight of the scientific evidence. Definitions of those terms have also 
been added. While EPA prefers high quality data, where available, EPA 
recognizes that data is not always necessary to reach a scientifically 
grounded conclusion on the potential risks of a chemical substance, 
within the timeframes dictated by the statute.
    As a matter of practice, EPA has been, and will continue to be, 
committed to basing its decisions on the best available science and the 
weight of the scientific evidence. In response to public comments on 
the proposal, EPA has determined to make a number of additions to the 
final rule to ensure that the science standards in TSCA are more 
explicitly incorporated into the risk evaluation process. Specifically, 
EPA has added specific language to the final rule stating that EPA will 
evaluate hazard and exposure data in a manner consistent with the 
section 26 science standards including documenting the use of the 
standards in 15 U.S.C. 2625(h) and the weight of the scientific 
evidence in 15 U.S.C. 2625(i). These changes clarify that EPA's risk 
evaluations will be consistent with TSCA's new requirements in section 
26 related to best available science and weight of the scientific 
evidence.
    d. Fit-for-purpose risk evaluations. As described in the proposed 
rule and in Unit III.D.10, each risk evaluation will be fit-for-
purpose--that is to say, the level of refinement will vary as necessary 
to determine whether the chemical substance presents an unreasonable 
risk, given the nature of the evidence, for the conditions of use of a 
specific chemical substance. A number of the public comments received 
stated their support for this approach, as it conserves the Agency's 
resources to focus on the most important components of a given risk 
evaluation.
    EPA introduced the idea that risk evaluations would be conducted in 
a fit-for-purpose manner in the proposed rule. Specifically, EPA stated 
that all conditions of use evaluated will not warrant the same level of 
evaluation, and that EPA expects, that in some cases, it may be able to 
reach conclusions without extensive or quantitative evaluations of 
risk. For example, a lower-volume or less dispersive (those uses that 
do not spread as far in the environment, either indoors or outdoors as 
compared to a different use) condition of use might require a less 
quantitative, data-driven evaluations to credibly characterize the 
risks than uses with more extensive or complicated exposure patterns. 
Consistent with EPA's current practice in conducting risk assessments, 
technically sound risk determinations can be made, consistent with the 
best available science, through a combination of different types of 
information and methods approaches.

[[Page 33740]]

EPA will continue to utilize this approach and has retained it in the 
final rule. The concept of fit-for-purpose risk evaluations is further 
explained in the regulation as follows: EPA will refine, as necessary, 
its evaluations for one or more conditions of use in any risk 
evaluation and when information and analysis are sufficient to make a 
risk determination using assumptions, uncertainty factors, and models 
or screening methodologies, EPA may decide not to refine its analysis 
further. Both of these provisions give EPA the flexibility to conduct 
risk evaluations in a manner that best suits the available information 
and the decisions that will be made. These are generally consistent 
with the proposed text, however some changes have been made, namely the 
exclusion of the phrase ``accepted science policies.'' A number of 
commenters expressed concern regarding the lack of clarity of this 
language. Commenters asked for specific examples of science policies 
and some commenters expressed concern that the Agency would confuse 
science with regulatory policy, and specifically encouraged separation 
between the two, to ensure that EPA's decisions would be science-based. 
To address these concerns EPA has deleted the reference to ``science 
policies'' from the rule text.
    Many commenters suggested that this fit-for-purpose approach would 
be necessary to evaluate chemical substances within the statutory 
timeframe, and agreed that this is appropriate because due to the 
nature of some uses, some will not necessitate the same level of 
evaluation as others. By contrast, some commenters were concerned that 
the fit-for-purpose approach is not scientifically sound and can never 
be objective. To clarify, EPA will not sacrifice best available science 
in implementing this approach. The speed of an evaluation does not 
equate to less rigorous science. EPA will always be transparent about 
the data and assumptions used.
    e. Timing of a risk determinations. In the proposed rule, EPA 
explicitly allowed for the expedited evaluation for a particular 
condition of use to, if necessary, move more rapidly to risk management 
under TSCA section 6(a) (15 U.S.C. 2605(a). This could include a 
situation in which a single use presented an unreasonable risk of 
injury for the population as a whole or for a susceptible subpopulation 
(e.g., one use results in risks that EPA would determine unreasonable 
regardless of the risk posed by other uses). A number of commenters 
raised concern about the apparent one-sided nature of this provision, 
arguing that this appeared to preclude a similar determination that a 
chemical substance did not present an unreasonable risk. EPA agrees 
that logically such determinations could be appropriate in either case, 
and has revised its approach to apply more generally. Accordingly, the 
final regulation at 720.41(a)(7) has been revised to clarify that EPA 
may make early risk determinations that a chemical substance does or 
does not present an unreasonable risk under particular conditions of 
use. The final rule also makes clear that any expedited determination 
may be issued at any point after the final scope is published. As 
discussed previously, all early determinations would be portions of the 
final, complete risk evaluation and would therefore be made using the 
procedures applicable to TSCA risk evaluations established in this 
rule. TSCA is very clear that unreasonable risk determinations cannot 
be made until after a risk evaluation that meets the requirements of 
section 6(b)(4) is complete. Any risk evaluation for a chemical under 
particular conditions of use will therefore be consistent with all 
statutory requirements as well as the procedures established in this 
regulation. This would also include the requirement that EPA publish a 
draft risk evaluation for no less than a 60-day public comment period, 
and the regulatory requirement for peer review.
    The final regulation also continues to explicitly state that in any 
case where EPA would find it necessary to issue an early risk 
determination for a chemical substance under particular conditions of 
use of a chemical, the Agency will still complete a risk evaluation on 
all conditions of use identified in the final scope, within the 
statutory 3-year deadline. In sum, the final rule explicitly recognizes 
that EPA may make early risk determinations, to either to manage 
unreasonable risks as they are identified, through the issuance of a 
regulation under TSCA section 6(a) or to notify the public as soon as 
possible of the safety of a chemical substance under a particular 
condition of use.
    f. Metals or metal compounds. As required by the statute, when 
evaluating metals or metal compounds, EPA must use the March 2007 
Framework for Metals Risk Assessment of the Office of the Science 
Advisor (Ref. 3) or a successor document that addresses metals risk 
assessment and is peer- reviewed by the Science Advisory Board. The 
final rule, consistent with the proposal, merely reiterates this 
statutory mandate.
    2. Information and information sources. For those chemical 
substances designated as high priority for risk evaluation, EPA expects 
to initiate the process when EPA has determined that most of the 
information necessary to complete the evaluation is reasonably 
available, which in most cases means the information already exists. In 
the proposal, EPA had stated that the goal would be to ``only'' 
initiate the process once most of the information necessary to complete 
the evaluation was reasonably available. In the final rule the word 
``only'' has been deleted to account for the fact that EPA may use its 
regulatory authorities to obtain or require the generation of 
additional information even after the risk evaluation has been 
initiated.
    For manufacturer requested risk evaluations, EPA acknowledges it 
may potentially be difficult to gather all of the necessary information 
prior to risk evaluation, as these chemicals will not have gone through 
the prioritization process. Nevertheless, EPA generally expects that it 
will be feasible to obtain the necessary information to complete a risk 
evaluation within the statutory timeframe. As discussed previously, the 
final rule requires a manufacturer to submit all of the necessary 
hazard information for EPA to complete a risk evaluation on the one or 
more conditions of use that have been requested. Although there may be 
other hazards associated with other conditions of use that present 
different routes of exposure, EPA expects that the majority of the 
necessary hazard information will be obtained through the request. EPA 
has then allotted 195 days from receipt of request to gather additional 
information required to assess both requested uses and any additional 
conditions of use EPA has determined warrant evaluation. For both EPA- 
and manufacturer-initiated risk evaluations, EPA may also rely on 
information developed through the use of novel and advancing chemical 
assessment procedures, measures, methods, protocols, methodologies, or 
models (e.g., high-throughput chemical assessment techniques).
    For identified data needs, EPA may issue a voluntary call to the 
public for relevant information or otherwise engage directly with 
stakeholders, followed, as necessary, by exercise of EPA's authorities 
under TSCA to require submission or generation of new data. 
Accordingly, as appropriate, EPA will exercise its TSCA information 
collection, testing, and subpoena authorities, including those under 
TSCA sections 4, 8, and 11(c) to obtain the information needed for a 
risk evaluation. EPA notes as well that TSCA section 8(e) requires that 
any person who manufacturers, processes, or

[[Page 33741]]

distributes in commerce a chemical substance or mixture and who obtains 
information which supports the conclusion that this substance or 
mixture presents a substantial risk of injury to health or the 
environment, shall immediately inform the Agency, and EPA may obtain 
some information through this route.
    EPA also expects to obtain scientific advice from the Science 
Advisory Committee on Chemicals (SACC), which the Agency is required to 
develop and convene under TSCA section 26(o).
    When conducting a risk evaluation, EPA will ensure that risk 
evaluations are consistent with the scientific standards in section 
26(h) and (i), including reliance on the best available science and the 
weight of the scientific evidence. EPA will rely on data, models, and 
screening methods, as needed. The use of these methods will be balanced 
by the quality of the information (consistent with standards in section 
26(h) and (i)) and the statutory deadlines for completing a risk 
evaluation. In the final rule, EPA will use the scope to focus on the 
reasonably available information and science approaches, and reserve 
uncertainty considerations specifically for the remainder of the risk 
evaluation.
    EPA does not intend to preclude the generation of new scientific 
information to inform risk evaluations, however, as mentioned in the 
discussion of reasonably available information, the extent to which EPA 
will consider any newly generated information in a risk evaluation will 
depend on the statutory deadlines.
    In compliance with the statute, EPA will work to reduce and 
replace, to the extent practicable, the use of vertebrate animals in 
testing chemical substances as outlined in TSCA section 4(h). The 
intent to reduce testing on animals was in the proposed text, however 
comments suggested the language was not exactly as the statute 
intended, and that it should refer to the development of new 
information, not all existing information, as it could have been 
interpreted. The final rule text has been amended to more closely hew 
to the statute.

I. Risk Evaluation Steps

    1. Scope. The first step of a risk evaluation is the development of 
the scope. The scope of each risk evaluation will include the following 
components. The conditions of use, as determined by the Administrator, 
that the EPA plans to consider in the risk evaluation will be included 
in the scope. This is amended from the proposed rule to address the 
approach to conditions of use as explained in Unit III.B. The EPA will 
identify the potentially exposed or susceptible subpopulations EPA 
expects to consider, the ecological receptors, and the hazards to human 
health and the environment the Agency plans to evaluate will also be 
included. From the proposed rule, EPA changed ``ecological 
characteristics'' to ``ecological receptors.'' This was done to clarify 
that the Agency will be evaluating specifically the impact of the 
chemical stressor, and EPA believes that characteristics was too broad, 
and receptors more closely hew a chemical risk assessment. The scope 
will include a description of the reasonably available information and 
the science approaches that the Agency plans to use. In the proposed 
rule EPA had included that the reasonably available information would 
include ``accepted science policies (e.g., defaults and uncertainty 
factors), models, and screening methodologies.'' As already discussed, 
a number of commenters expressed their concern with this language and 
in response EPA removed this provision. Under the final rule, the scope 
will focus on the reasonably available information and science 
approaches, and reserve uncertainty considerations specifically for the 
remainder of the risk evaluation.
    EPA will include a conceptual model that will describe the actual 
or predicted relationships between the chemical substance and the 
receptors, either human or environmental, with consideration of 
potential hazards throughout the life cycle of the chemical substance--
from manufacturing, processing, distribution in commerce, storage, use, 
to release or disposal.
    Also included will be an analysis plan, which will identify the 
approaches and methods EPA plans to use to assess exposure, hazards, 
which will include dose-response, and risk, including associated 
uncertainty and variability. The analysis plan will also include a 
description of the reasonably available information and science 
approaches the EPA plans to use.
    As requested by a number of commenters, the scope will also include 
the plan for peer review the Agency expects to consider. This may 
include the plan for peer review for those conditions of use that EPA 
expects to make early risk determinations on. This plan may also 
include the Agency's plan to have any methods or models peer reviewed, 
along with the risk evaluation, as well as the EPA's anticipated use of 
the SACC or another peer review body or whether the Agency anticipates 
a letter peer review or a committee consensus peer review. The Peer 
Review Handbook walks through the numerous options the Agency can use, 
and the plan will give the public an idea of what the Agency intends to 
use for a particular risk evaluation.''
    EPA will publish a notice in the Federal Register, announcing the 
availability of the final scope within six months of the initiation of 
the risk evaluation. Although not required under the statute, EPA will 
publish a draft scope and provide for no less than a 45 calendar day 
public comment period during this six-month period. As a number of 
commenters pointed out, there was a mistake in the proposed rule--the 
length of the commenter period on the draft scope was 30 days in the 
preamble, but 45 days in the regulatory text. EPA has corrected this 
mistake. EPA welcomes all public participation, but specifically 
encourages commenters to provide information they believe might be 
missing or may further inform the risk evaluation. That said, the 
prioritization process requires two public comment opportunities, and 
EPA expects this will reduce the likelihood of significant comments on 
the draft scope for those High-priority chemicals.
    EPA has deleted the issue preclusion clause included in the 
proposed rule stating that ``any issues related to the scope not raised 
in the comments at that time cannot form the basis for an objection or 
challenge in a future administrative or judicial hearing'' in response 
to a significant number of comments. However, under general principles 
of administrative law, commenters are required to identify relevant 
available information and raise objections that could be raised during 
established comment periods, and courts generally will require 
commenters to have done so as a matter of exhaustion of administrative 
remedies. EPA has concluded that these principles provide sufficient 
assurance that commenters will raise timely objections and provide 
timely information and has therefore decided to strike the proposed 
regulatory text.
    2. Hazard assessment. In compliance with TSCA section 6(b)(4)(F), 
EPA will conduct a hazard assessment on each chemical substance or 
category, under the conditions of use as identified in the scope. A 
hazard assessment identifies the types of adverse health or 
environmental effects or hazards that can be caused by exposure to the 
chemical substance in question, and to characterize the quality and 
weight of the scientific evidence supporting this identification. 
Hazard identification is the process of determining whether exposure to 
a chemical stressor can

[[Page 33742]]

cause an increase in the incidence of specific adverse health or 
environmental effects (e.g., cancer, developmental toxicity). All 
information used in this assessment will be reviewed in a manner 
consistent with reliance on the best available science and a weight of 
the scientific evidence approach.
    As the rule text indicates, EPA will present the hazard 
information, as identified in the scope, for the identified exposure 
scenarios, and including any identified potentially exposed or 
susceptible subpopulation. From the proposed rule, EPA changed the word 
``endpoints'' to ``hazards,'' as hazards is more general and inclusive.
    The hazard assessment will identify the types of hazards to human 
health and the environment. The information will be reviewed in a 
manner consistent with use of the best available science and with the 
weight of scientific evidence. This will include the identification, 
evaluation, and synthesis of information to describe the potential 
health and environmental hazards of the chemical, under the conditions 
of use, and all assessment methods will be documented. This hazard 
assessment may include, but may not be limited to, evaluation of the 
potential toxicity of the chemical substance with respect to cancer, 
mutation, reproductive, developmental, respiratory, immune, and 
cardiovascular impacts, and neurological impairments. The assessment 
may evaluate effects at life stage(s) most appropriate for a receptor 
target.
    A hazard assessment also will include a dose-response assessment. A 
dose-response relationship describes how the likelihood and severity of 
adverse health effects (the responses) are related to the amount and 
condition of exposure to an agent (the dose provided). The same 
principles generally apply for studies where the exposure is to a 
concentration of the agent (e.g., airborne concentrations applied in 
inhalation exposure studies or water or other media concentrations for 
ecological exposure studies), and the resulting information is referred 
to as the concentration-response.
    Potential information sources that may support the hazard 
assessment include but are not limited to: Population based 
epidemiological studies that identify risk factors and susceptible 
subpopulations; information related to geographic location of 
subpopulations; models that represent health effects of relevant 
subpopulation; in vivo and/or in vitro laboratory studies; mechanistic 
or kinetic studies in a variety of test systems, including but not 
limited to toxicokinetics and toxicodynamics, and computational 
toxicology, which the final rule makes clear may include high-
throughput assays, genomic response assays, data from structure-
activity relationships, and ecological field data. The hazard 
identification will also include an evaluation of the strength, 
limitations, and uncertainties associated with the reasonably available 
information. The final rule was amended to include uncertainties as 
commenters encouraged EPA to further discuss how uncertainties will be 
addressed in this process.
    Specifically, for human health hazards, the assessment will 
consider all potentially exposed or susceptible subpopulation(s) 
identified in the scope. EPA will use an appropriate combination, if 
available, of population-based epidemiological studies, information 
related to geographic location of susceptible subpopulations, models 
representing health effects to the population, and any other 
information or methodology consistent with scientific standards.
    An environmental hazard assessment will evaluate the relationship 
between the chemical substance and the occurrence of an ecological 
response. This assessment may be conducted using reasonably available 
information from field or laboratory data, modeling strategies, and 
species extrapolations, if needed.
    Changes from the proposed rule include the addition of EPA's 
commitment to using the best available science and a weight of the 
evidence approach. Some specific details regarding the available 
information that may be used in hazard assessments have been moved to 
this preamble. The proposal stated that EPA ``may include'' followed by 
a list of types of information, and although the phrase ``may include'' 
provides flexibility, EPA believes that it is more appropriate to not 
codify this level of specific detail in the regulation. Many public 
comments encouraged transparency in the Agency's risk evaluation 
process, but because this rule must cover the process for all risk 
evaluations, which by nature will necessitate the consideration of many 
types of information sources, EPA believes the better (and ultimately 
more accurate) approach is to ensure that it provides full transparency 
in the individual risk evaluations.
    3. Exposure assessment. Pursuant to TSCA section 6(b)(4)(F), EPA, 
``where relevant, will take into account the likely duration, 
intensity, frequency, and number of exposures under the conditions of 
use in an exposure assessment.'' An exposure assessment will include 
information on chemical-specific factors, including but not limited to: 
Physical-chemical properties and environmental fate and transport 
parameters. These considerations were included in the proposed rule; 
however ``transport'' has been added to the final text. Fate and 
transport in environmental media are commonly assessed together, and 
this is more consistent with EPA's current practices. EPA has also 
added a statement in the rule text regarding the use of best available 
science and weight of scientific evidence approaches. As stated 
elsewhere in the preamble, EPA is committed to upholding these 
statutory requirements.
    An exposure assessment includes some discussion of the size, 
nature, and types of individuals or populations exposed to the agent, 
as well as discussion of the uncertainties in this information. 
Exposure can be measured directly, but when data is unavailable it is 
estimated indirectly through consideration of measured concentrations 
in the environment, consideration of models of chemical transport and 
fate in the environment, and estimates of human intake or environmental 
exposure over time. A number of commenters encouraged the use of 
probabilistic approaches as they provide better estimates of exposure 
when compared to specific ``bright line'' approaches. In response EPA 
will strive to utilize probabilistic approaches for exposure 
assessments included in a risk evaluation but has not revised the 
proposed regulation, consistent with its approach to other provisions, 
where EPA has moved many of the specific approaches that appeared in 
the proposed rule text into the final preamble. EPA believes that this 
level of detail regarding the specific information types used in risk 
evaluation is more appropriate for guidance. Commenters had also 
suggested that guidance is more appropriate for specific methods and 
approaches because it can be amended easily to adopt to changing 
science. Codifying specific methods could unnecessarily restrict the 
Agency's ability to review all pertinent information.
    Using reasonably available information, exposures will be estimated 
(usually quantitatively) for the identified conditions of use. For 
human health exposure, the assessment would consider all potentially 
exposed or susceptible subpopulation(s) identified in the scope and 
utilize any combination, as available, of population-based 
epidemiological studies, information related to

[[Page 33743]]

geographic location of susceptible subpopulations, models representing 
exposures to the population, measurements in human tissues or relevant 
environmental or exposure media, and any other relevant, scientifically 
valid information or methodology. In an environmental health exposure 
assessment the interaction of the chemical substance with any 
ecological characteristics identified in the scope will be 
characterized and evaluated. As with the hazard assessment, specific 
details on the source of information EPA will use have been moved to 
this preamble to allow for flexibility in identifying the appropriate 
sources of information.
    4. Risk characterization. TSCA requires that a risk evaluation 
``integrate and assess available information on hazards and 
exposures.'' (15 U.S.C 2605(b)(4)(F)). A risk characterization conveys 
the risk assessor's judgment as to the nature and presence or absence 
of risks, along with information about how the risk was assessed, where 
assumptions and uncertainties still exist, and where policy choices 
will need to be made. Risk characterization takes place for both human 
health risk assessments and ecological risk assessments. The proposed 
text only included the necessity for EPA to describe whether aggregate 
or sentinel exposures were considered during the risk evaluation and 
the basis for that consideration. The final rule text was amended to 
include all of the statutory requirements of the risk evaluation 
process, including: Not considering costs or other non-risk factors; 
taking into account the likely duration, intensity, frequency, and 
number of exposures under the condition(s) of use; and a description of 
the weight of scientific evidence for the identified hazards and 
exposures. The statute requires a risk evaluation to include all of 
these components, so EPA believed it was necessary to codify them all, 
rather than to single out just one of the requirements.
    In the risk characterization summary, EPA will further carry out 
the obligations under TSCA section 26; for example, by identifying and 
assessing uncertainty and variability in each step of the risk 
evaluation, discussing considerations of data quality such as the 
reliability, relevance and whether the methods utilized were reasonable 
and consistent, explaining any assumptions used, and discussing 
information generated from independent peer review. 15 U.S.C. 2625(h). 
EPA may include a discussion of alternative interpretations, where 
these interpretations are plausible, of results generated from the risk 
evaluation. EPA amended the regulation text to include the phrase 
``where these interpretations are plausible,'' because EPA believes, in 
agreement with a commenter, that through the use of best available 
science and weight of scientific evidence approaches, it is feasible 
that not every risk evaluation will have alternative interpretations. 
EPA wants to be clear that alternative interpretations will be 
presented in the risk characterization on a case-by-case basis, but may 
not be the norm, as requested by another commenter.
    For environmental evaluations specifically, EPA plans to include a 
discussion of the nature and magnitude of the effects, the spatial and 
temporal patterns of the effects, implications at the species, 
population, and community level, and the likelihood of recovery 
subsequent to exposure to the chemical substance. A few commenters 
suggested that when conducting an ecological risk assessment, it is 
important to consider the population level, as this was not included in 
the proposed rule. The commenters' suggestion more accurately reflects 
EPA's general practices for ecological risk assessments and this change 
has been made in the final rule.
    In practice, each component of the risk assessment (e.g., hazard 
assessment, dose-response assessment, exposure assessment) has an 
individual characterization written to carry forward the key findings, 
assumptions, limitations, and uncertainties. The set of these 
individual characterizations provide the information basis to write an 
integrative risk characterization analysis. The final, overall risk 
characterization thus consists of the individual component 
characterizations plus an integrative analysis. Each risk evaluation 
will quantitatively and/or qualitatively estimate and characterize risk 
for the identified populations and ecological characteristics under the 
conditions of use.
    EPA has historically used a MOE approach in risk characterization 
of TSCA risk assessments. The proposed rule asked the public to comment 
on the strengths and weaknesses of the MOE approach. EPA received many 
comments with thoughtful reasoning both for and against using this 
approach. As discussed by commenters, the benefits of the MOE approach 
include the assertion that the approach is more transparent than other 
approaches, such as a hazard index or hazard quotient, because the 
application of uncertainty factors is transparent, and that the MOE 
approach can incorporate data from multiple pathways and endpoints. 
Some supporters of the MOE approach did encourage EPA to not prescribe 
a single value that would be used for all risk evaluations, but to 
select a MOE value that is fit-for-purpose and specifically associated 
with the evidence of the evaluation.
    Commenters that were not supportive of this approach expressed 
their concern for this ``bright line'' approach, in that it does not 
reflect knowledge about what the potential risks are above or below the 
`line,' and that it assumes a safe level of exposure below which harm 
will not occur. Others commented that the MOE approach is not always 
easily communicated to the public. Many commenters suggested 
alternatives, including the use of probabilistic approaches, arguing 
that they better account for variability and uncertainty. Finally, 
others commented that it was not appropriate to call out specific 
methods, as this is more appropriate for guidance.
    Agreeing with the consensus from the comments, EPA acknowledges 
that MOE is just one of many ways to characterize risk. There will be 
risk scenarios where one approach may be better than another, and as 
commenters correctly pointed out, the science of risk characterization 
is still evolving, particularly for non-cancer hazards. To account for 
the number of different approaches and for changing science, EPA will 
not codify any specific method in this final rule.
    Finally, EPA will utilize EPA's Information Quality Guidelines in 
the risk characterization section of the risk evaluation, as it 
provides guidance for presenting risk information (Ref. 5). As 
explained in that document, EPA should identify: (1) Each population 
addressed by an estimate of applicable risk effects; (2) the expected 
risk or central estimate of risk for the potentially exposed or 
susceptible subpopulations affected; (3) each appropriate upper-bound 
or lower-bound estimate of risk; (4) each significant uncertainty 
identified in the process of the assessment of risk effects and the 
studies that would assist in resolving the uncertainty; and (5) peer-
reviewed studies known to the Agency that support, are directly 
relevant to, or fail to support any estimate of risk effects and the 
methodology used to reconcile inconsistencies in the scientific 
information.
    5. Peer review. For each risk evaluation conducted on chemicals 
identified pursuant to TSCA section 6(b)(4)(A), EPA will conduct a peer 
review using the guidance provided in executive branch peer review 
directives, including in the Office of Management and Budget Final 
Information Quality

[[Page 33744]]

Bulletin for Peer Review (OMB Bulletin) (Ref. 18) and in the EPA Peer 
Review Handbook (2015) (Ref. 19) or its updates. For those conditions 
of use that may receive an early determination of no unreasonable risk, 
EPA will ensure that the risk assessments underlying these 
determinations are reviewed in a manner consistent with the OMB 
Bulletin and the EPA Peer Review Handbook. These documents do provide 
some latitude for the type of peer review that EPA can conduct, which 
EPA will take advantage of. For example, in determining the appropriate 
type of peer review, EPA can consider the complexity of the information 
and any prior peer review of underlying information. EPA may also 
utilize the SACC in reviewing the science that underlies these 
determinations.
    As discussed in the proposed rule, EPA will identify aspects of the 
analysis on which peer review will be conducted, and the planned 
methodologies, as part of the draft scoping document that will undergo 
public comment for each chemical substance that undergoes risk 
evaluation. These may include novel models or analyses that warrant an 
in-depth peer review. In addition to any targeted peer review of 
specific aspects of the analysis, the entire risk assessment will also 
undergo peer review, as it is important for peer reviewers to consider 
how the various underlying analyses fit together to produce an 
integrated risk characterization, which will form the basis of an 
unreasonable risk determination. A number of commenters argued for 
involvement of the public into the peer review process. To respond to 
this, EPA plans to take public comment on the charge questions given to 
peer reviewers.
    The peer review will address aspects of the science underlying the 
assessment, including, but not limited to hazard assessment, assessment 
of dose-response, exposure assessment, and risk characterization. 
Consistent with the proposed rule, EPA will not seek review of any 
determination as to whether the risks are ``unreasonable,'' which is an 
Agency policy determination. EPA did receive public comment requesting 
that the risk determination also be subject to peer review; however, 
EPA strongly believes that the purpose of peer review is for the 
independent review of the science underlying the risk assessment, not 
an evaluation of EPA's policy determinations. TSCA expressly reserves 
to the Agency the final determination of whether risk posed by a 
chemical substance is ``unreasonable.'' 15 U.S.C. 2605(i). EPA 
nevertheless will include its risk determination as part of the risk 
evaluation that is subject to public review and comment.
    EPA specifically requested public comment on whether there are 
circumstances where conducting peer review may not be warranted, (e.g., 
what circumstances may require peer review and if there are others that 
may not) and whether the regulatory text should be adjusted to require 
EPA to make a case by case determination of whether and to what extent, 
consistent with the EPA Peer Review Handbook, peer review is warranted 
for the chemical substance undergoing a risk evaluation. The comments 
received were generally very supportive of conducting a peer review on 
all risk evaluations. There were some comments that encouraged 
discretion as to whether peer review had to be conducted on a 
particular risk evaluation (e.g., determinations of no unreasonable 
risk, or on evaluations were the result was consistent with other 
national or international conclusions). Commenters also raised issues 
regarding the timing of peer review in the risk evaluation process 
(e.g., after public comment), what should and should not be included in 
peer review (e.g., the risk determination), and views on what type of 
peer review should be conducted (e.g., full panel review). EPA's 
responses to specific comments are addressed in the response to comment 
document.
    Accordingly, EPA has retained the provision from the proposed rule 
requiring peer review on all risk evaluations. Guidance on how peer 
review will be conducted will remain consistent with the EPA Peer 
Review Handbook. For clarity, EPA did move the peer review provision to 
its own section of the rule, as suggested by a commenter. EPA agrees 
with comments that peer reviewed evaluations will instill greater 
confidence and provide transparency to the process. EPA postulated in 
the proposed rule that there may be circumstances that may not 
necessitate peer review (e.g., where a chemical substance is found to 
not present an unreasonable risk or that findings are similar or the 
same as other jurisdictions (states or countries) that have reached 
similar conclusions based on the same information). Public comment 
presented arguments to why this is not appropriate. Although a 
substance may not present an unreasonable risk, the consequence of a 
`false negative' could be extremely problematic. For the second 
scenario where EPA's results may be similar to another jurisdiction's, 
commenters argued that it will also be necessary to peer review the 
evaluation. It would be necessary to make certain the best available 
science and weight of the scientific evidence approaches were used 
properly, as they may not have been required under the process by which 
the comparable evaluation was conducted. As such, EPA will require peer 
review on all risk evaluations.
    6. Unreasonable risk determination. The final step of a risk 
evaluation is for EPA to determine whether the chemical substance, 
under the conditions of use, presents an unreasonable risk of injury to 
health or the environment. EPA will make individual risk determinations 
for all uses identified in the scope. This part of the regulation is 
slightly amended from the proposed rule, to clarify that the risk 
determination is part of the risk evaluation, as well as to account for 
the revised approach to that ensures each condition of use covered by 
the risk evaluation receives a risk determination. Due to EPA's 
decision to allow for early determinations on one or more conditions of 
use, where appropriate, risk determinations may be published in 
multiple documents or in a single document containing all risk 
determinations for all identified uses. If the determinations are 
published in multiple documents, the final determination will be a 
composite document of all determinations made. EPA's determinations 
will specify whether each condition of use identified for a chemical 
substance does or does not present an unreasonable risk of injury to 
health or the environment. A determination that a condition of use does 
not present an unreasonable risk is considered to be a final EPA 
action. If EPA determines that the chemical substance, under one or 
more condition of use, does present an unreasonable risk, EPA must 
initiate a rulemaking pursuant to TSCA section 6(a) to impose 
requirements to the extent necessary so that the substance no longer 
presents such risk. 15 U.S.C. 2605(a). Any rule would apply only to the 
condition(s) of use that present an unreasonable risk, and those that 
do not present an unreasonable risk will not be subject to risk 
management. A number of commenters asked EPA to communicate clearly 
which uses may go to risk management following the evaluation. EPA will 
clarify in the draft and final risk evaluation documents specifically 
which condition(s) of use warrant risk management and which do not.
    7. Reassessment of unreasonable risk determination. EPA stated in 
the proposed rule that it may reassess determinations of unreasonable 
risk. A number of commenters requested clarification on when and how 
this

[[Page 33745]]

might happen. Following review of the comments, EPA has deleted the 
provision as it was unnecessary. Generally, agencies are authorized to 
revisit determinations they are charged by statute to make, and nothing 
in TSCA prevents EPA from doing that. EPA is also concerned that the 
provision could have been read as an effort to limit, expand, or 
otherwise alter the statutory authority.
    8. Additional publicly available information. Pursuant to TSCA 
section 26(j), and subject to TSCA section 14, the final regulation 
specifies that EPA will make available: (1) The draft scope, final 
scope, draft risk evaluation, and final risk evaluation; (2) All 
notices, determinations, findings, consent agreements, and orders; (3) 
Any information required to be provided to the Agency under 15 U.S.C. 
2603; (4) A nontechnical summary of the risk evaluation; (5) A list of 
the studies, with the results of the studies, considered in carrying 
out each risk evaluation; (6) Each determination as to whether the 
chemical substance presents an unreasonable risk under one or more 
conditions of use, along with an identification of the information, 
analysis, and basis used to make the designation; (7) The final peer 
review report, including the response to peer review and public 
comments received during peer review; and (8) Response to public 
comments received on the draft scope and the draft risk evaluation. In 
this final rule there are a few slight changes from the proposed 
regulation, largely to conform to changes made to other sections of the 
rule. The final rule now includes number 6, which has been slightly 
amended from the statute to make clear that EPA will be making public 
its risk determinations (the statute uses the term ``designations''). 
In addition, the final regulation now specifies and that these 
determinations will be made for the chemical under the one or more 
conditions of use identified in the risk evaluation.

IV. Summary of Request for Specific Public Comment on the Proposed Rule

    In the Proposed Risk Evaluation Rule, EPA requested specific public 
input on a number of subjects. These subjects are listed below along 
with reference of the particular section where EPA has discussed the 
public comment.
    1. Redefining scientific terms. Unit III.D.
    2. Margin of Exposure. Unit III.D.13.
    3. Systematic Review. Unit III.D.12.
    4. Manufacturer requests. Unit II.A.2.
    5. Peer Review. Unit III.G.5.
    6. Reliance on existing guidance and procedures for conducting risk 
evaluations. Unit III.G.1.a.
    7. Interagency collaboration. Unit III.H.

V. Cost Analysis

    Industry costs for this rule are limited to activities a 
manufacturer must perform in order to meet the requirements outlined in 
previous sections. Manufacturers are not required to submit a chemical 
substance for risk evaluation, therefore these costs will only be 
experienced when a given manufacturer chooses to make a submission to 
the Agency. The fully loaded wage rate of a technical professional 
(i.e., toxicologist) of $78.40 was used to calculate the cost of labor 
burden.

A. Number of Entities Affected

    EPA developed estimates for the number of manufacturers who are 
likely to elect to submit a chemical substance for risk evaluation. 
Since submissions of this nature have never been collected by the 
Agency before, the actual number of expected submittals is relatively 
unknown. However, EPA assumes 5 chemical manufacturers may submit 
requests to the Agency in any given year. The Agency will not be 
required to perform 20 risk evaluations at any given time until 2 years 
after rule finalization. Based on this, assuming 25 percent of total 
risk evaluations coming from manufacturer submissions was considered a 
best estimate with the lack of actual data. The total number of 
entities affected by the recordkeeping and reporting requirements of 
the rule, therefore, is estimated to be 5 chemical manufacturers per 
year.

B. Rule Familiarization Burden

    EPA assumes that each manufacturer who elects to submit a chemical 
substance for risk evaluation consideration is assumed to spend one 
hour becoming familiar with the requirements of the rule and developing 
an understanding of what actions are necessary to complete the forms 
and submission package. This is separate from the time it takes to 
create the submission package itself.
    The total cost of rule familiarization is estimated to be $392 per 
year (5 x 1 x 78.40 = 392).

C. CDX Electronic Reporting Burden

    Manufacturers requesting a chemical substance be considered by EPA 
for risk evaluation are required to provide the submission package to 
the Agency via the CDX electronic system. While several manufacturers 
may be familiar with the CDX system and are registered users because 
the same system is used for new chemical submissions to the Agency 
(e.g., pre-manufacture notice, significant new use notice, low volume 
exemptions) there is no way to estimate which manufacturers submitting 
risk evaluation requests are familiar with CDX and which are new to the 
system. Therefore, EPA assumes submissions under this rule are 
performed by new users of CDX which may result in an overestimate of 
burden.
    The CDX electronic reporting burden includes registration to CDX, 
familiarization with the subscriber agreements, potential use of the 
help desk, and problem resolution. The burden estimates used in this 
rule are based off of estimates in EPA ICR No. 2502.02, resulting in a 
burden of 2.83 hours per respondent.
    The total cost of CDX electronic reporting burden is estimated to 
be $1,109 per year (5 x 2.83 x 78.40 = 1,109).

D. Submission Package Burden

    Chemical manufacturers electing to request EPA consider a chemical 
substance for risk evaluation must provide a submission package 
including the following information: Contact information of requesting 
entity(s), full chemical identity information, complete list of 
reasonably available information consistent with TSCA section 26(h) 
standards that is relevant to an unreasonable risk determination, 
addresses all the circumstances that constitute conditions of use, of 
interest to the manufacturer, within the meaning of TSCA section 3, 
contain a commitment to provide EPA any referenced information upon 
request of the Agency, and provide a signed certification that all 
information in the submission is accurate and complete.
    While submissions of this nature have never been required or 
requested by EPA in the past, the Agency has performed similar tasks 
internally while conducting previous Risk Evaluations. The average 
contractor expense and labor time the Agency spends on the types of 
activities required to prepared the submission package covered by this 
rule were used to develop the burden and cost estimates.
    EPA estimates the cost of having a contractor conduct an in-depth 
literature review and screen the literature found for relevance costs 
an average of $50,000 per chemical. This includes the cost of using 
literature review databases and the contractor labor time involved in 
performing the review and screening activities. In addition to the 
contractor cost, the

[[Page 33746]]

manufacturer is expected to spend an average of 80 hours per chemical 
reviewing the data found during the literature, refining the searches 
as needed, and preparing the submission package. Therefore, the 
estimated burden for developing and submitting a risk evaluation 
request is 80 hours per respondent with an additional direct cost of 
$50,000 per submission package.
    Total cost for submission package burden is estimated to be 
$281,360 per year (5 x 50,000 x 80 x 78.40 = 281,360).

E. Total Cost

    The total annual cost for this rule is estimated to be $282,861 per 
year (392 + 1,109 + 281,360 = 282,861) under the assumption EPA 
receives 5 manufacturer requests per year. Manufacturers choosing to 
submit a chemical substance for risk evaluation may be a small entity. 
Due to the low cost ($56,572) of a single submission package, the cost 
of the voluntary submission is expected to impact less than 1% of the 
small business at greater than 3% of average revenue in the estimated 
universe of small businesses.

VI. References

    The following is a listing of the documents that are specifically 
referenced in this document. The docket includes these documents and 
other information considered by EPA, including documents that are 
referenced within the documents that are included in the docket, even 
if the referenced document is not physically located in the docket. For 
assistance in locating these other documents, please consult the 
technical person listed under FOR FURTHER INFORMATION CONTACT.

1. USEPA. Information Collection Request (ICR) for the Proposed 
Rule: Procedures for Chemical Risk Evaluation Under TSCA. EPA ICR 
No.: 2559.01 and OMB No. 2070--[NEW].
2. EPA. TSCA Work Plan Chemical Assessments: 2014 Update-Final. 
Office of Pollution Prevention and Toxics. October 2014. https://www.epa.gov/sites/production/files/2015-01/documents/tsca_work_plan_chemicals_2014_update-final.pdf.
3. EPA. Framework for Metals Risk Assessment of the Office of the 
Science Advisor, Risk Assessment Forum. Washington, DC. March 2007.
4. USEPA. Exposure Factors Handbook. EPA/600/R-090/052F. Office of 
Research and Development, National Center for Environmental 
Assessment. Washington, DC. 2011. https://cfpub.epa.gov/ncea/risk/recordisplay.cfm?deid=236252.
5. Guidelines for Ensuring and Maximizing the Quality, Objectivity, 
Utility, and Integrity of Information Disseminated by the 
Environmental Protection Agency. EPA/260R-02-008. Washington, DC. 
2002. https://www.epa.gov/sites/production/files/2015-08/documents/epa-info-quality-guidelines.pdf.
6. European Centre for Ecotoxicology and Toxicology of Chemicals 
(ECETOC). Targeted Risk Assessment User Guide. version 3.1. June 
2014. http://www.ecetoc.org/wp-content/uploads/2014/06/Ecetoc_Tra_Standalone_Consumer_Tool_User_Guide_Jun2014.pdf.
7. Toxicology Excellence for Risk Assessment (TERA). Complex 
Exposure Tool (ComET) Meeting Materials. 2009. http://www.tera.org/Peer/Exposure/ExposureMeetingMaterials.htm.
8. USEPA. Framework for Human Health Risk Assessment to Inform 
Decision Making. EPA/100/R-14/001 Office of the Science Advisor, 
Risk Assessment Forum. 2014. https://archive.epa.gov/raf/web/pdf/hhra-framework-final-2014.pdf.
9. National Research Council. Science and Decisions: Advancing Risk 
Assessment. The National Academies Press. Washington, DC. 2009.
10. USEPA. Weight of Evidence in ecological risk assessment. Office 
of Research and Development. Washington, DC. 2016.
11. Institute of Medicine. Finding What works in Health Care: 
Standards for Systematic Reviews. p. 13-34. The National Academies 
Press. Washington, DC. 2011.
12. J. Higgins and S. Green. Cochrane Handbook for Systematic 
Reviews of Interventions. John Wiley & Sons. 2011.
13. National Research Council. Review of EPA's Integrated Risk 
Information System (IRIS) Process. Board on Environmental Studies 
and Toxicology. Washington, DC. 2014.
14. Stephens, M.F., Betts, K., Beck, N.B., Cogliano, V., Dickersin, 
K., Fitzpatrick S., Freeman, J., Gray, G., Hartung T., McPartland, 
J., Rooney A.A., Scherer R.W., Verloo, D., Hoffmann, S. The 
Emergence of Systematic Review in Toxicology. Toxicological 
Sciences. 152 (1): 10-16. 2016. DOI: https://doi.org/10.1093/toxsci/kfw059.
15. USEPA. Risk Assessment Guidelines. https://www.epa.gov/risk/risk-assessment-guidelines.
16. USEPA. Pesticide Science and Assessing Pesticide Risks. https://www.epa.gov/pesticide-science-and-assessing-pesticide-risks.
17. USEPA. Predictive Models and Tools for Assessing Chemicals under 
the Toxic Substances Control Act (TSCA). https://www.epa.gov/tsca-screening-tools.
18. Office of Management and Budget Final Information Quality 
Bulletin for Peer Review. Washington, DC. 2004. https://19january2017snapshot.epa.gov/sites/production/files/2015-01/documents/omb_final_info_quality_bulletin_peer_review_2004_1.pdf.
19. USEPA. Peer Review Handbook. 3rd ed. EPA/100/B-06/002. Science 
Policy Council. Washington, DC. 2006. https://www.epa.gov/osa/peer-review-handbook-4th-edition-2015.

VII. Statutory and Executive Order Reviews

    Additional information about these statutes and Executive Orders 
can be found at http://www2.epa.gov/laws-regulatios/laws-and-executive-orders.

A. Executive Order 12866: Regulatory Planning and Review and Executive 
Order 13563: Improving Regulation and Regulatory Review

    This action is a significant regulatory action that was submitted 
to the Office of Management and Budget (OMB) for review under Executive 
Orders 12866 (58 FR 51735, October 4, 1993) and 13563 (76 FR 3821, 
January 21, 2011), and any changes made in response to OMB 
recommendations are documented in the docket. EPA conducted an analysis 
of the potential costs associated with this action. This analysis, can 
be found in Unit V. This action is not subject to the requirements of 
Executive Order 13771, entitled ``Reducing Regulation and Controlling 
Regulatory Costs'' (82 FR 9339, February 3, 2017) because this rule 
results in no more than de mimimis costs.

B. Paperwork Reduction Act (PRA)

    The information collection activities associated with this rule 
have been submitted to OMB for review and approval under the PRA, 44 
U.S.C. 3501 et seq. Specifically, EPA has prepared an ICR to estimate 
the potential burden and costs associated with the requirements for 
submitting a request for an Agency-conducted risk evaluation on a 
particular chemical substance. The ICR, which is available in the 
docket, has been assigned the EPA ICR number 2559.01. You can find a 
copy of the ICR in the docket for this rule (Ref. [Insert reference 
#]), and it is briefly summarized here.
    Respondents/Affected Entities: Manufacturers (including importers).
    Respondent's Obligation to Respond: Optional, i.e., needed only if 
they are requesting an EPA-conducted risk evaluation for a particular 
chemical substance.
    Estimated Number of Respondents: 5.
    Frequency of Response: On occasion.
    Total Estimated Annual Burden: 419.2 hours. Burden is defined in 5 
CFR 1320.3(b).
    Total Estimated Annual Cost: $282,861 for burden hours. There are 
no O&M costs.
    An agency may not conduct or sponsor, and a person is not required 
to respond to a collection of information unless it displays a 
currently valid OMB control number. The OMB control numbers for the 
EPA's regulations in 40 CFR are listed in 40 CFR part 9.

[[Page 33747]]

C. Regulatory Flexibility Act (RFA)

    EPA certifies under section 605(b) of the RFA, 5 U.S.C. 601 et 
seq., that this action will not have a significant economic impact on a 
substantial number of small entities. Although this rule primarily 
addresses internal EPA procedures and activities associated with 
conducting risk evaluations for chemical substances as required by 
TSCA, EPA is also including the process and content requirements for a 
manufacturer (including importer) to request that EPA conduct a risk 
evaluation on particular uses of interest of a chemical substance. EPA 
has determined that the process and content requirements proposed will 
have minimal impact on an entity, regardless of size, because there is 
no mandate for them to make such a request, and the information they 
must provide should they decide to make such a request, which involves 
basic information about the chemical substance and the manufacturer's 
reasons for requesting the EPA-conducted risk evaluation on that 
chemical substance, should be readily available to the manufacturer. 
Estimated potential burden and costs are presented in the ICR (Ref. 1).
    EPA developed estimates for the number of manufacturers likely to 
submit a request for a chemical substance to be considered for a risk 
evaluation. EPA has never collected submissions of this nature in the 
past, so the actual number of expected submissions is unknown. EPA 
estimates five manufacturer-requested submissions may be sent to EPA in 
any given year. Based on the average number of manufacturers (and small 
businesses) per chemical for the ten chemicals initially identified by 
EPA for risk evaluation, EPA estimates an average of 35 manufacturers 
will be involved with the five manufacturer-requested submissions for 
risk evaluations each year. Of the 35 affected manufacturers, 15 are 
estimated to be small businesses. Based on the ten chemicals initially 
identified by EPA for risk evaluations, there are an average of seven 
manufacturers per chemical. Assuming that submission costs are shared 
equally within a consortium of seven manufacturers, the one-time 
respondent cost of $56,572 per submission would be $8,082 per 
manufacturer.
    Based on revenue data from U.S. Census Statistics of US Business 
and an estimated cost of $8,082 per manufacturer, EPA estimated the 
proportion of small manufacturer firms that could have a cost impact of 
less than 1%; between 1% and 3%; and more than 3% of the average 
revenues. The proportion of small business firms which may incur a cost 
impact of less than 1% of the average revenues is 76% of the small 
firms (approximately 11 of the 15 affected small manufacturers). The 
proportion of small business firms which may incur a cost impact 
between 1% and 3% of the average revenues is 23% of the small firms 
(approximately 3 of the 15 affected small manufactures). The proportion 
of small business firms which may incur a cost impact greater than 3% 
of the average revenues is 1% of the small firms (approximately 1 of 
the 15 small manufacturers).
    The decision to request a risk assessment for a chemical is 
voluntary and manufacturers may decide not to make such a request. But 
if such a request is made, the burden for the needed paperwork still 
does not result in a significant economic impact on a substantial 
number of small entities.

D. Unfunded Mandates Reform Act (UMRA)

    This Action does not contain any unfunded mandate as described in 
UMRA, 2 U.S.C. 1531-1538, and does not significantly or uniquely affect 
small governments. The action imposes no enforceable duty on any state, 
local or tribal governments or the private sector.

E. Executive Order 13132: Federalism

    This action does not have federalism implications as specified in 
Executive Order 13132 (64 FR 43255, August 10, 1999). It will not have 
substantial direct effects on the states, on the relationship between 
the national government and the states, or on the distribution of power 
and responsibilities among the various levels of government.

F. Executive Order 13175: Consultation and Coordination With Indian 
Tribal Governments

    This action does not have tribal implications as specified in 
Executive Order 13175 (65 FR 67249, November 9, 2000). It will not have 
substantial direct effects on one or more Indian tribes, on the 
relationship between the Federal Government and Indian tribes, or on 
the distribution of power and responsibilities between the Federal 
Government and Indian tribes. Thus, Executive Order 13175 does not 
apply to this action.

G. Executive Order 13045: Protection of Children From Environmental 
Health Risks and Safety Risks

    The EPA interprets Executive Order 13045 (62 FR 19885, April 23, 
1997) as applying only to those regulatory actions that concern 
environmental health or safety risks that the EPA has reason to believe 
may disproportionately affect children, per the definition of ``covered 
regulatory action'' in section 2-201 of the Executive Order. This 
action is not subject to Executive Order 13045 because it does not 
concern an environmental health risk or safety risk.

H. Executive Order 13211: Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use

    This action is not a ``significant energy action'' as defined in 
Executive Order 13211 (66 FR 28355, May 22, 2001), because it is not 
likely to have a significant adverse effect on the supply, distribution 
or use of energy.

I. National Technology Transfer and Advancement Act (NTTAA)

    This action does not involve any technical standards, and is 
therefore not subject to considerations under NTTAA section 12(d), 15 
U.S.C. 272 note.

J. Executive Order 12898: Federal Actions To Address Environmental 
Justice in Minority Populations and Low-Income Populations

    This action does not establish an environmental health or safety 
standard, and is therefore not subject to environmental justice 
considerations under Executive Order 12898 (59 FR 7629, February 16, 
1994). This is a procedural rule that will not affect the level of 
protection provided to human health or the environment.

K. Congressional Review Act (CRA)

    This action is subject to the CRA, 5 U.S.C. 801 et seq., and EPA 
will submit a rule report to the U.S. Senate, and the U.S. House of 
Representatives, and the Comptroller General of the United States. This 
action is not a ``major rule'' as defined by 5 U.S.C. 804(2).

List of Subjects in 40 CFR Part 702

    Environmental protection, Chemicals, Chemical substances, Hazardous 
substances, Health and safety, Risk evaluation.

    Dated: June 22, 2017.
E. Scott Pruitt,
Administrator.

    Therefore, 40 CFR chapter I, subchapter R, is amended as follows:

PART 702--[AMENDED]

0
1. The authority citation for part 702 is revised to read as follows:

     Authority:  15 U.S.C. 2605 and 2619.


0
2. Add subpart B to read as follows:

[[Page 33748]]

Subpart B--Procedures for Chemical Substance Risk Evaluations

Sec.
702.31 General provisions.
702.33 Definitions.
702.35 Chemical substances designated for risk evaluation.
702.37 Submission of manufacturer requests for risk evaluations.
702.39 Interagency collaboration.
702.41 Evaluation requirements.
702.43 Risk Characterization.
702.45 Peer review.
702.47 Unreasonable risk determination.
702.49 Risk evaluation timeframes and actions.
702.51 Publically available information.


Sec.  702.31  General provisions.

    (a) Purpose. This subpart establishes the EPA process for 
conducting a risk evaluation to determine whether a chemical substance 
presents an unreasonable risk of injury to health or the environment as 
required under TSCA section 6(b)(4)(B) (15 U.S.C. 2605(b)(4)(B)).
    (b) Scope. These regulations establish the general procedures, key 
definitions, and timelines EPA will use in a risk evaluation conducted 
pursuant to TSCA section 6(b) (15 U.S.C. 2605(b)).
    (c) Applicability. The requirements of this part apply to all 
chemical substance risk evaluations initiated pursuant to TSCA section 
6(b) (15 U.S.C. 2605(b)).
    (d) Enforcement. Submission to EPA of inaccurate, incomplete, or 
misleading information pursuant to a risk evaluation conducted pursuant 
to 15 U.S.C. 2605(b)(4)(B) is a prohibited act under 15 U.S.C. 2614, 
subject to penalties under 15 U.S.C. 2615 and Title 18 of the U.S. 
Code.


Sec.  702.33  Definitions.

    All definitions in TSCA apply to this subpart. In addition, the 
following definitions apply:
    Act means the Toxic Substances Control Act, as amended (15 U.S.C. 
2601 et seq.).
    Aggregate exposure means the combined exposures to an individual 
from a single chemical substance across multiple routes and across 
multiple pathways.
    Best available science means science that is reliable and unbiased. 
Use of best available science involves the use of supporting studies 
conducted in accordance with sound and objective science practices, 
including, when available, peer reviewed science and supporting studies 
and data collected by accepted methods or best available methods (if 
the reliability of the method and the nature of the decision justifies 
use of the data). Additionally, EPA will consider as applicable:
    (1) The extent to which the scientific information, technical 
procedures, measures, methods, protocols, methodologies, or models 
employed to generate the information are reasonable for and consistent 
with the intended use of the information;
    (2) The extent to which the information is relevant for the 
Administrator's use in making a decision about a chemical substance or 
mixture;
    (3) The degree of clarity and completeness with which the data, 
assumptions, methods, quality assurance, and analyses employed to 
generate the information are documented;
    (4) The extent to which the variability and uncertainty in the 
information, or in the procedures, measures, methods, protocols, 
methodologies, or models, are evaluated and characterized; and
    (5) The extent of independent verification or peer review of the 
information or of the procedures, measures, methods, protocols, 
methodologies or models.
    Conditions of use means the circumstances, as determined by the 
Administrator, under which a chemical substance is intended, known, or 
reasonably foreseen to be manufactured, processed, distributed in 
commerce, used, or disposed of.
    EPA means the U.S. Environmental Protection Agency.
    Pathways means the mode through which one is exposed to a chemical 
substance, including but not limited to: Food, water, soil, and air.
    Potentially exposed or susceptible subpopulation means a group of 
individuals within the general population identified by the Agency who, 
due to either greater susceptibility or greater exposure, may be at 
greater risk than the general population of adverse health effects from 
exposure to a chemical substance or mixture, such as infants, children, 
pregnant women, workers, or the elderly.
    Reasonably available information means information that EPA 
possesses or can reasonably generate, obtain, and synthesize for use in 
risk evaluations, considering the deadlines specified in TSCA section 
6(b)(4)(G) for completing such evaluation. Information that meets the 
terms of the preceding sentence is reasonably available information 
whether or not the information is confidential business information, 
that is protected from public disclosure under TSCA section 14.
    Routes means the particular manner by which a chemical substance 
may contact the body, including absorption via ingestion, inhalation, 
or dermally (integument).
    Sentinel exposure means the exposure from a single chemical 
substance that represents the plausible upper bound of exposure 
relative to all other exposures within a broad category of similar or 
related exposures.
    Uncertainty means the imperfect knowledge or lack of precise 
knowledge of the real world either for specific values of interest or 
in the description of the system.
    Variability means the inherent natural variation, diversity, and 
heterogeneity across time and/or space or among individuals within a 
population.
    Weight of scientific evidence means a systematic review method, 
applied in a manner suited to the nature of the evidence or decision, 
that uses a pre-established protocol to comprehensively, objectively, 
transparently, and consistently, identify and evaluate each stream of 
evidence, including strengths, limitations, and relevance of each study 
and to integrate evidence as necessary and appropriate based upon 
strengths, limitations, and relevance.


Sec.  702.35  Chemical substances designated for risk evaluation.

    (a) Chemical substances undergoing risk evaluation. A risk 
evaluation for a chemical substance designated by the Agency as a High-
Priority Substance pursuant to the prioritization process described in 
subpart A, identified under 15 U.S.C. 2605(b)(2)(A), or initiated at 
the request of a manufacturer or manufacturers under Sec.  702.37, will 
be conducted in accordance with this part, except that risk evaluations 
that are initiated prior to the effective date of this rule will be 
conducted in accordance with this part to the maximum extent 
practicable.
    (b) Percentage requirements. The Agency will ensure that, of the 
number of chemical substances that undergo risk evaluation under 15 
U.S.C. 2605(b)(4)(C)(i), the number of chemical substances undergoing 
risk evaluation under 15 U.S.C. 2605(b)(4)(C)(ii) is not less than 25%, 
if sufficient requests that comply with 702.37, and not more than 50%.
    (c) Manufacturer requests for work plan chemical substances. 
Manufacturer requests for risk evaluations, described in paragraph (a) 
of this section, for chemical substances that are drawn from the 2014 
update of the TSCA Work Plan for Chemical Assessments will be granted 
at the discretion of the Agency. Such evaluations are not subject to 
the percentage requirements in paragraph (b) of this section.

[[Page 33749]]

Sec.  702.37  Submission of manufacturer requests for risk evaluations.

    (a) General provision. Any request that EPA conduct a risk 
evaluation pursuant to this part must comply with all the procedures 
and criteria in this section to be eligible to be granted by EPA.
    (b) Method for submission. One or more manufacturers of a chemical 
substance may request that EPA conduct a risk evaluation. All requests 
submitted to EPA under this subpart must be submitted via the EPA 
Central Data Exchange (CDX) found at http://cdx.epa.gov. Requests must 
include all of the following information:
    (1) Name, mailing address, and contact information of the entity 
(or entities) submitting the request. If more than one manufacturer 
submits the request, all individual manufacturers must provide their 
contact information.
    (2) The chemical identity of the chemical substance that is the 
subject of the request. At a minimum, this includes, all known names of 
the chemical substance, including common or trades names, CAS number, 
and molecular structure of the chemical substance A request for risk 
evaluations of a category of chemical substances must include an 
explanation of why the category is appropriate under 15 U.S.C. 2625(c), 
and EPA will grant such request only upon determining that the 
requested category is appropriate for risk evaluation.
    (3) The manufacturer must identify the circumstances on which they 
are requesting that EPA conduct a risk evaluation and include a 
rationale for why these circumstances constitute conditions of use 
under Sec.  702.33.
    (4) The request must also include a list of all the existing 
information that is relevant to whether the chemical substance, under 
the circumstances identified by the manufacturer(s), presents an 
unreasonable risk of injury to health or the environment. The list must 
be accompanied by an explanation as to why such information is adequate 
to permit EPA to complete a risk evaluation addressing the 
circumstances identified by the manufacturer(s), The request need not 
include copies of the information; citations are sufficient, if the 
information is publically available. The request must include or 
reference all available information on the health and environmental 
hazard(s) of the chemical substance, human and environmental 
exposure(s), and exposed population(s), as relevant to the 
circumstances identified in the request. At a minimum, this must 
include all the following, as relevant to the circumstances identified:
    (i) The chemical substance's hazard and exposure potential;
    (ii) The chemical substance's persistence and bioaccumulation;
    (iii) Potentially exposed or susceptible subpopulations which the 
manufacturer(s) believes to be relevant to the EPA risk evaluation;
    (iv) Whether there is any storage of the chemical substance near 
significant sources of drinking water, including the storage facility 
location and the nearby drinking water source(s);
    (v) The chemical substance's production volume or significant 
changes in production volume; and
    (vi) Any other information relevant to the potential risks of the 
chemical substance under the circumstances identified in the request.
    (5) The request must include a commitment to provide to EPA any 
referenced information upon request.
    (6) Scientific information submitted must be consistent with the 
scientific standards in 15 U.S.C. 2625(h).
    (7) A signed certification that all information contained in the 
request is accurate and complete, as follows:
    (i) I certify that to the best of my knowledge and belief:
    (A) The company named in this request manufacturers the chemical 
substance identified for risk evaluation.
    (B) All information provided in the notice is complete and accurate 
as of the date of the request.
    (C) I have either identified or am submitting all information in my 
possession, control, and a description of all other data known to or 
reasonably ascertainable by me as required for this request under this 
part. I am aware it is unlawful to knowingly submit incomplete, false 
and/or misleading information in this request and there are significant 
criminal penalties for such unlawful conduct, including the possibility 
of fine and imprisonment.
    (ii) [Reserved]
    (c) Optional elements. A manufacturer may provide information that 
will inform EPA's determination as to whether restrictions imposed by 
one or more States have the potential to have a significant impact on 
interstate commerce or health or the environment, and that as a 
consequence the request is entitled to preference pursuant to 15 U.S.C. 
2605(b)(4)(E)(iii).
    (d) Confidential business information. (1) Persons submitting a 
request under this subpart are subject to EPA confidentiality 
regulations at 40 CFR part 2, subpart B.
    (2) In submitting a claim of confidentiality, a person must certify 
the accuracy of the following statements concerning all information 
claimed as confidential:
    (i) I hereby certify to the best of my knowledge and belief that 
all information entered on this form is complete and accurate. I 
further certify that, pursuant to 15 U.S.C. 2613(c), for all claims for 
confidentiality made with this submission, all information submitted to 
substantiate such claims is true and correct, and that it is true and 
correct that:
    (A) My company has taken reasonable measures to protect the 
confidentiality of the information;
    (B) I have determined that the information is not required to be 
disclosed or otherwise made available to the public under any other 
Federal law;
    (C) I have a reasonable basis to conclude that disclosure of the 
information is likely to cause substantial harm to the competitive 
position of my company; and
    (D) I have a reasonable basis to believe that the information is 
not readily discoverable through reverse engineering.
    (ii) [Reserved]
    (3) Each claim of confidentiality, other than a claim pertaining to 
information described in TSCA section 14(c)(2), must be accompanied by 
a substantiation in accordance with 15 U.S.C. 2613.
    (4) Manufacturers must supply a structurally descriptive generic 
name where specific chemical identity is claimed as CBI.
    (5) Any knowing and willful misrepresentation, under this section, 
is subject to criminal penalty pursuant to 18 U.S.C. 1001.
    (e) EPA process for evaluating manufacturer requests--(1) Review 
for completeness. Upon receipt of the request, EPA will verify that the 
request is facially complete, i.e., that information has been submitted 
that appears to be consistent with the requirements in paragraphs (b) 
through (d) of this section. EPA will inform the submitting 
manufacturer(s) if EPA has determined that the request is incomplete, 
and cannot be processed. Facially complete requests will be processed 
as described in this subpart.
    (2) Public notification of receipt of request. Within 15 business 
days of receipt of a facially complete submission, EPA will notify the 
public of receipt of the manufacturer request. This notification will 
include any information submitted by the manufacturer that is not CBI, 
including the condition(s) of use for which the evaluation is 
requested.
    (3) Conditions of use to be evaluated. EPA will assess whether the 
circumstances identified in the request constitute condition of use 
under

[[Page 33750]]

Sec.  702.33, and whether those conditions of use warrant inclusion 
within the scope of a risk evaluation for the chemical substance. EPA 
will also assess what, if any, additional conditions of use that 
warrant inclusion within the scope of a risk evaluation for the 
chemical substance. EPA will conduct these assessments and make 
proposed determinations based on the same considerations applied in the 
same manner as it would for a risk evaluation for a high-priority 
substance.
    (4) Public notice and comment. No later than 60 business days of 
receiving a request that EPA has determined to be complete under 
paragraph (e)(1) of this section, EPA will submit for publication the 
receipt of the request in the Federal Register, open a docket for that 
request and provide no less than a 45 calendar day public comment 
period. The docket will contain the manufacturer request (excluding 
information claimed as CBI) and EPA' proposed additions of conditions 
of use as described in paragraph (e)(3) of this section, and the basis 
for these proposed additions. During the comment period the public may 
submit comments and information relevant to the requested risk 
evaluation, in particular, commenters are encouraged to identify any 
information not included in the request or the proposed determinations 
that the commenters believe would be needed to conduct a risk 
evaluation, and to provide any other information relevant to EPA's 
proposed determinations of the conditions of use, such as information 
on other conditions of use of the chemical than those included in the 
request or in EPA's proposed determinations
    (5) Supplementation of original request. (i) At any time prior to 
the end of the comment period, the requesting manufacturer(s) may 
supplement the original request with any new information it receives.
    (ii) At any point prior to the completion of a risk evaluation 
pursuant to this section, manufacturer(s) must supplement the original 
request with any information that meets the criteria in 15 U.S.C. 
2607(e) and this section, or with any other information that has the 
potential to change EPA's risk evaluation with respect to the 
conditions of use as requested by the manufacturer. Such information 
must be submitted consistent with section 8(e) if the information is 
subject to that section or otherwise within 30 calendar days of the 
manufacturer's obtaining the information.
    (6) EPA's decision. (i) Within 60 days of the end of the comment 
period provided in paragraph (e)(4) of this section, EPA will review 
the request along with any additional information received during the 
comment period to determine whether the request meets the criteria and 
requirements of this section.
    (ii) EPA will grant the request if it determines that all of the 
following have been met:
    (A) That the circumstances identified in the request constitute 
conditions of use that warrant inclusion in a risk evaluation for the 
chemical substance;
    (B) That EPA has all of the information needed to conduct such risk 
evaluation on the conditions of use that were the subject of the 
request; and
    (C) All other criteria and requirements of this section have been 
met.
    (iii) At the end of this 60-day period, EPA will notify the 
submitting manufacturer(s) of its decision and include the basis for 
granting or denying the request. Bases for a denial, include the 
manufacturer has not provided sufficient information to complete the 
risk evaluation on the condition(s) of use requested, or that the 
circumstances identified in the request either do not constitute 
conditions of use, or the conditions of use do not warrant inclusion in 
a risk evaluation for the chemical substance. This notification will 
also identify any additional conditions of use, as determined by the 
Administrator, that will be included in this risk evaluation.
    (iv) Within 30 days of receipt of EPA's notification the 
requester(s) may withdraw the request.
    (7) Public notice of decision. EPA will make public EPA's decision 
to grant or deny the request at the time that EPA notifies the 
manufacturer.
    (8) Compliant request. EPA will initiate a risk evaluation for all 
requests for non-TSCA Work Plan Chemicals that meet the criteria in 
this subpart, until EPA determines that the number of manufacturer-
requested chemical substances undergoing risk evaluation is equal to 
25% of the High-Priority Substances identified in subpart A as 
undergoing risk evaluation. Once that level has been reached, EPA will 
initiate at least one new manufacturer-requested risk evaluation for 
each manufacturer-requested risk evaluation completed so long as there 
are sufficient requests that meet the criteria of this subpart, as 
needed to ensure that the number of manufacturer-requested risk 
evaluations is equal to at least 25% of the High-Priority substances 
risk evaluation and not more than 50%.
    (9) Preferences. In conformance with Sec.  702.35(c), in evaluating 
requests for TSCA Work Plan Chemicals and requests for non-TSCA Work 
Plan chemicals in excess of the 25% threshold in Sec.  702.35(b), EPA 
will first give preference to requests for risk evaluations on chemical 
substances:
    (i) First, for which the Agency determines that restrictions 
imposed by one or more States have the potential to have a significant 
impact on interstate commerce, health or the environment; and then
    (ii) Second, based on the order in which the requests are received.
    (10) No preferential treatment. Once granted, EPA will initiate the 
risk evaluation and thereafter will conduct the risk evaluation 
following the procedures in Sec. Sec.  702.39 through 702.51. EPA will 
not expedite or otherwise provide special treatment to a risk 
evaluation conducted as a result of a manufacturer's request.
    (11) Fees. Manufacturers must pay fees to support risk evaluations 
as specified under 15 U.S.C. 2605(b)(4)(E)(ii).


Sec.  702.39  Interagency collaboration.

    During the risk evaluation process, not to preclude any additional, 
prior, or subsequent collaboration, EPA will consult with other 
relevant Federal agencies.


Sec.  702.41  Evaluation requirements.

    (a) Considerations. (1) Each risk evaluation will include all of 
the following components:
    (i) A Scope, including a Conceptual Model and an Analysis Plan;
    (ii) A Hazard Assessment;
    (iii) An Exposure Assessment;
    (iv) A Risk Characterization; and
    (v) A Risk Determination.
    (2) EPA guidance will be used, as applicable where it represents 
the best available science appropriate for the particular risk 
evaluation.
    (3) Where appropriate, a risk evaluation will be conducted on a 
category of chemical substances. EPA will determine whether to conduct 
an evaluation on a category of chemical substances, and the composition 
of the category based on the considerations listed in 15 U.S.C. 
2625(c).
    (4) EPA will document that it has used the best available science 
and weight of scientific evidence approaches in the risk evaluation 
process.
    (5) EPA will ensure that all supporting analyses and components of 
the risk evaluation are suitable for their intended purpose, and well-
tailored to the problems and decision at hand, in order to inform the 
development of a technically sound determination as to whether a 
chemical substance presents an unreasonable risk of injury to health or 
the environment under the

[[Page 33751]]

conditions of use within the scope of the risk evaluation, based on the 
weight of the scientific evidence.
    (6) The extent to which EPA will refine its evaluations for one or 
more condition of use in any risk evaluation will vary as necessary to 
determine whether a chemical substance presents an unreasonable risk of 
injury to health or the environment.
    (7) To the extent a determination as to the level of risk presented 
by a condition of use can be made, for example, using assumptions, 
uncertainty factors, and models or screening methodologies, EPA may 
determine that no further information or analysis is needed to complete 
its risk evaluation of the condition(s) of use.
    (8) In general, EPA intends to determine whether a chemical 
substance does or does not present an unreasonable risk under all of 
the conditions of use within the scope of the risk evaluations, and 
intends to identify the individual conditions of use or categories of 
conditions of use that are responsible for such determinations.
    (9) Within the time frame in Sec.  702.43(d), EPA will complete the 
risk evaluation of the chemical substance addressing all of the 
conditions of use within the scope of the evaluation. However, EPA may 
complete its evaluation of the chemical substance under specific 
conditions of use or categories of conditions of use at any point 
following the issuance of the final scope document, and issue its 
determination as to whether the chemical substance under those 
conditions of use does or does not present an unreasonable risk to 
health or the environment under those conditions of use. EPA will 
follow all of the requirements and procedures in this Subpart when it 
conducts its evaluation of the chemical substance under any individual 
or specific conditions of use.
    (10) EPA will evaluate chemical substances that are metals or metal 
compounds in accordance with 15 U.S.C. 2605(b)(2)(E).
    (b) Information and information sources. (1) EPA will base each 
risk evaluation on reasonably available information.
    (2) EPA generally expects to initiate a risk evaluation for a 
chemical substance when EPA believes that all or most of the 
information necessary to perform the risk evaluation is reasonably 
available. EPA expects to use its authorities under the Act, and other 
information gathering authorities, when necessary to obtain the 
information needed to perform a risk evaluation for a chemical 
substance before initiating the risk evaluation for such substance. EPA 
will use such authorities on a case-by-case basis during the 
performance of a risk evaluation to obtain information as needed to 
ensure that EPA has adequate, reasonably available information to 
perform the evaluation.
    (3) Among other sources of information, the Agency will consider 
information and advice provided by the Science Advisory Committee on 
Chemicals established pursuant to 15 U.S.C. 2625.
    (4) In conducting risk evaluations, EPA will utilize reasonably 
available information including information, models, and screening 
methodologies, as appropriate. The approaches used will be determined 
by the quality of the information, the deadlines specified in TSCA 
section 6(b)(4)(G) for completing the risk evaluation, and the extent 
to which the information reduces uncertainty.
    (5) Where appropriate, to the extent practicable, and 
scientifically justified, EPA will require the development of 
information generated without the use of new testing on vertebrates in 
performing risk evaluation.
    (c) Scope of the risk evaluation. The scope of the risk evaluation 
will include all the following:
    (1) The condition(s) of use, as determined by the Administrator, 
that the EPA plans to consider in the risk evaluation.
    (2) The potentially exposed populations, including any potentially 
exposed or susceptible subpopulations as identified as relevant to the 
risk evaluation by the Agency under the conditions of use, that EPA 
plans to evaluate; the ecological receptors that EPA plans to evaluate; 
and the hazards to health and the environment that EPA plans to 
evaluate.
    (3) A description of the reasonably available information and 
science approaches EPA plans to use in the risk evaluation.
    (4) A conceptual model:
    (i) The scope documents will include a Conceptual Model that 
describes actual or predicted relationships between the chemical 
substance, the conditions of use within the scope of the evaluation and 
human and environmental receptors.
    (ii) The conceptual model will identify human and ecological health 
hazards the EPA plans to evaluate for the exposure scenarios EPA plans 
to evaluate.
    (iii) Conceptual model development will consider the life cycle of 
the chemical substance, including manufacture, processing, distribution 
in commerce, storage, use, and disposal, relevant to the conditions of 
use within the scope of the evaluation
    (5) An analysis plan:
    (i) The scope documents will include an analysis plan that 
identifies the approaches, methods, and/or metrics that EPA plans to 
use to assess exposures, effects, and risk, including associated 
uncertainty and variability for each risk evaluation. The analysis plan 
will also identify the strategy for using information, accepted science 
policies, models, and screening methodologies.
    (ii) Hypotheses about the relationships identified in the 
conceptual model will be described. The relative strengths of 
alternative hypotheses if any will be evaluated to determine the 
appropriate risk assessment approaches.
    (6) The Agency's plan for peer review.
    (7) Developing the scope.
    (i) Draft scope. For each risk evaluation to be conducted EPA will 
publish a document in the Federal Register that specifies the draft 
scope of the risk evaluation the Agency plans to conduct. The document 
will address the elements in paragraphs (c)(1) through (6) of this 
section.
    (ii) Timeframes. EPA generally expects to publish the draft scope 
no later than 3 months from the initiation of the risk evaluation 
process for the chemical substance.
    (iii) Public comments. EPA will allow a public comment period of no 
less than 45 calendar days during which interested persons may submit 
comment on EPA's draft risk evaluation scope. EPA will open a docket to 
facilitate receipt of public comments.
    (8) Final scope:
    (i) The Agency will, no later than 6 months after the initiation of 
a risk evaluation, publish a document in the Federal Register that 
specifies the final scope of the risk evaluation the Agency plans to 
conduct. The document shall address the elements in paragraphs (c)(1) 
through (6) of this section.
    (ii) For a chemical substance designated as a High-Priority 
Substance under subpart A of this part, EPA will not publish the final 
scope of the risk evaluation until at least 12 months have elapsed from 
the initiation of the prioritization process for the chemical 
substance.
    (d) Hazard assessment. (1) The hazard information relevant to the 
chemical substance will be evaluated using hazards identified in the 
final scope document published pursuant to paragraph (c)(8) of this 
section, for the identified exposure scenarios, including any 
identified potentially exposed or susceptible subpopulation(s).

[[Page 33752]]

    (2) The hazard assessment process will identify the types of 
hazards to health or the environment posed by the chemical substance 
under the condition(s) of use within the scope of the risk evaluation. 
Hazard information related to potential health and environmental 
hazards of the chemical substance will be reviewed in a manner 
consistent with best available science and weight of scientific 
evidence as defined in Sec.  702.33 and all assessment methods will be 
documented. This process includes the identification, evaluation, and 
synthesis of information to describe the potential health and 
environmental hazards of the chemical substance.
    (3) Relevant potential human and environmental hazards will be 
evaluated.
    (4) The relationship between the dose of the chemical substance and 
the occurrence of health and environmental effects or outcomes will be 
evaluated.
    (5) Studies evaluated may include, but would not be limited to: 
Human epidemiological studies, in vivo and/or in vitro laboratory 
studies, biomonitoring studies, mechanistic and/or kinetic studies in a 
variety of test systems, including but not limited to toxicokinetics 
and toxicodynamics, computational toxicology such as high-throughput 
assays, genomic response assays, data from structure-activity 
relationships, and ecological field data.
    (6) Hazard identification will include an evaluation of the 
strengths, limitations, and uncertainties associated with the 
reasonably available information.
    (7) The human health hazard assessment will consider all 
potentially exposed and susceptible subpopulation(s) determined to be 
relevant, as identified in the final scope document published pursuant 
to paragraph (c)(8) of this section.
    (8) The environmental health hazard assessment will consider the 
relationship between the chemical substance and the occurrence of an 
ecological hazard elicited.
    (e) Exposure assessment. (1) Where relevant, the likely duration, 
intensity, frequency, and number of exposures under the conditions of 
use will be considered.
    (2) Chemical-specific factors including, but not limited to: 
Physical- chemical properties and environmental fate and transport 
parameters will be examined.
    (3) Exposure information related to potential human health or 
ecological hazards of the chemical substance will be reviewed in a 
manner consistent with the description of best available science and 
weight of scientific evidence in Sec.  702.33 and all methods will be 
documented.
    (4) The human health exposure assessment will consider all 
potentially exposed and susceptible subpopulation(s) determined to be 
relevant, as identified in the final scope document published pursuant 
to paragraph (c)(8) of this section.
    (5) Environmental health exposure assessment:
    (i) The environmental health exposure assessment will characterize 
and evaluate the interaction of the chemical substance with the 
ecological receptors identified in the final scope document published 
pursuant to paragraph (c)(8) of this section.
    (ii) Exposures considered will include populations and communities, 
depending on the chemical substance and the ecological characteristic 
involved.


Sec.  702.43  Risk Characterization.

    (a) Risk Characterization considerations. EPA will:
    (1) Integrate the hazard and exposure assessments into quantitative 
and/or qualitative estimates of risk for the identified populations 
(including any potentially exposed or susceptible subpopulation(s)) 
identified in the final scope document published pursuant to Sec.  
702.41(c)(8) and ecological characteristics for the conditions of use 
within the scope of the risk evaluation;
    (2) Describe whether aggregate or sentinel exposures under the 
conditions of use were considered and the basis for their 
consideration;
    (3) Not consider costs or other nonrisk factors;
    (4) Take into account, where relevant, the likely duration, 
intensity, frequency, and number of exposures under the condition(s) of 
use of the chemical substance; and
    (5) Describe the weight of the scientific evidence for the 
identified hazards and exposures.
    (b) Risk Characterization summary. The Risk Characterization will 
summarize, as applicable, the considerations addressed throughout the 
evaluation components, in carrying out the obligations under 15 U.S.C. 
2625(h). This summary will include, as appropriate, a discussion of:
    (1) Considerations regarding uncertainty and variability. 
Information about uncertainty and variability in each step of the risk 
evaluation (e.g., use of default assumptions, scenarios, choice of 
models, and information used for quantitative analysis) will be 
integrated into an overall characterization and/or analysis of the 
impact of the uncertainty and variability on estimated risks. EPA may 
describe the uncertainty using a qualitative assessment of the overall 
strength and limitations of the data used in the assessment.
    (2) Considerations of data quality. A discussion of data quality 
(e.g., reliability, relevance, and whether methods employed to generate 
the information are reasonable for and consistent with the intended use 
of the information), as well as assumptions used, will be included to 
the extent necessary. EPA also expects to include a discussion of the 
extent of independent verification or peer review of the information or 
of the procedures, measures, methods, protocols, methodologies, or 
models used in the risk evaluation.
    (3) Considerations of alternative interpretations. If appropriate 
and relevant, where alternative interpretations are plausible, a 
discussion of alternative interpretations of the data and analyses will 
be included.
    (4) Considerations for environmental risk evaluations. For 
environmental risk evaluations, it may be necessary to discuss the 
nature and magnitude of the effects, the spatial and temporal patterns 
of the effects, implications at the individual, species, population, 
and community level, and the likelihood of recovery subsequent to 
exposure to the chemical substance.


Sec.  702.45  Peer review.

    The EPA Peer Review Handbook (2015), the Office of Management and 
Budget Final Information Quality Bulletin for Peer Review (OMB 
Bulletin), and other available, relevant and applicable methods 
consistent with 15 U.S.C. 2625, will serve as the guidance for peer 
review activities. Peer review will be conducted on the risk 
evaluations for the chemical substances identified pursuant to 15 
U.S.C. 2605(b)(4)(A).


Sec.  702.47  Unreasonable risk determination.

    As part of the risk evaluation, EPA will determine whether the 
chemical substance presents an unreasonable risk of injury to health or 
the environment under each condition of uses within the scope of the 
risk evaluation, either in a single decision document or in multiple 
decision documents.


Sec.  702.49  Risk evaluation timeframes and actions.

    (a) Draft risk evaluation timeframe. EPA will publish a draft risk 
evaluation in the Federal Register, open a docket to facilitate receipt 
of public comment,

[[Page 33753]]

and provide no less than a 60-day comment period, during which time the 
public may submit comment on EPA's draft risk evaluation.
    (b) Final risk evaluation. (1) EPA will complete a risk evaluation 
for the chemical substance under the conditions of use within the scope 
of the risk evaluation as soon as practicable, but not later than 3 
years after the date on which the Agency initiates the risk evaluation.
    (2) The Agency may extend the deadline for a risk evaluation for 
not more than 6 months. The total time elapsed between initiation of 
the risk evaluation and completion of the risk evaluation may not 
exceed 3 and one half years.
    (3) EPA will publish the final risk evaluation in the Federal 
Register.
    (c) Final determination of unreasonable risk. Upon determination by 
the EPA that a chemical substance under one or more of the conditions 
of use within the scope of the risk evaluation presents an unreasonable 
risk of injury to health or the environment as described in Sec.  
702.47, the Agency will initiate action as required pursuant to 15 
U.S.C. 2605(a).
    (d) Final determination of no unreasonable risk. A determination by 
EPA that the chemical substance, under one or more of the conditions of 
use within the scope of the risk evaluation, does not present an 
unreasonable risk of injury to health or the environment will be issued 
by order and considered to be a final Agency action, effective on the 
date of issuance of the order.


Sec.  702.51  Publically available information.

    For each risk evaluation, EPA will maintain a public docket at 
http://www.regulations.gov to provide public access to the following 
information, as applicable for that risk evaluation:
    (a) The draft scope, final scope, draft risk evaluation, and final 
risk evaluation;
    (b) All notices, determinations, findings, consent agreements, and 
orders;
    (c) Any information required to be provided to the Agency under 15 
U.S.C. 2603;
    (d) A nontechnical summary of the risk evaluation;
    (e) A list of the studies, with the results of the studies, 
considered in carrying out each risk evaluation;
    (f) The final peer review report, including the response to peer 
review and public comments received during peer review; and
    (g) Response to public comments received on the draft scope and the 
draft risk evaluation.

[FR Doc. 2017-14337 Filed 7-19-17; 8:45 am]
 BILLING CODE 6560-50-P