
[Federal Register Volume 88, Number 208 (Monday, October 30, 2023)]
[Proposed Rules]
[Pages 74292-74326]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-23428]



[[Page 74291]]

Vol. 88

Monday,

No. 208

October 30, 2023

Part III





Environmental Protection Agency





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40 CFR Part 702





Procedures for Chemical Risk Evaluation Under the Toxic Substances 
Control Act (TSCA); Proposed Rule

  Federal Register / Vol. 88 , No. 208 / Monday, October 30, 2023 / 
Proposed Rules  

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 702

[EPA-HQ-OPPT-2023-0496; FRL-8529-01-OCSPP]
RIN 2070-AK90


Procedures for Chemical Risk Evaluation Under the Toxic 
Substances Control Act (TSCA)

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The Environmental Protection Agency (EPA, ``the Agency'') is 
proposing to amend the procedural framework rule for conducting risk 
evaluations under the Toxic Substances Control Act (TSCA). The purpose 
of risk evaluations under TSCA is to determine whether a chemical 
substance presents an unreasonable risk of injury to health or the 
environment, without consideration of costs or non-risk factors, 
including unreasonable risk to potentially exposed or susceptible 
subpopulations identified as relevant to the risk evaluation by EPA, 
under the conditions of use. EPA has reconsidered the procedural 
framework rule for conducting such risk evaluations and determined that 
certain aspects of that framework should be revised to better align 
with applicable court decisions and the statutory text, to reflect the 
Agency's experience implementing the risk evaluation program following 
enactment of the 2016 TSCA amendments, and to allow for consideration 
of future scientific advances in the risk evaluation process without 
need to further amend the Agency's procedural rule.

DATES: Comments must be received on or before December 14, 2023. Under 
the Paperwork Reduction Act, comments on the information collection 
provisions are best assured of consideration if the Office of 
Management and Budget (OMB) receives a copy of your comments on or 
before November 29, 2023.

ADDRESSES: Submit your comments, identified by docket identification 
(ID) number EPA-HQ-OPPT-2023-0496, through the Federal eRulemaking 
Portal at https://www.regulations.gov. Follow the online instructions 
for submitting comments. Do not submit electronically any information 
you consider to be Confidential Business Information (CBI) or other 
information whose disclosure is restricted by statute. Additional 
instructions on commenting or visiting the docket, along with more 
information about dockets generally, is available at https://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) 564-4371; 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 proposing to amend procedural requirements that 
apply to the Agency's activities in carrying out TSCA risk evaluations. 
However, EPA is also proposing certain amendments to the process and 
requirements that manufacturers (including importers) would be required 
to follow when they request an Agency-conducted TSCA risk evaluation on 
a particular chemical substance. You may be potentially affected by 
this action if you manufacture or import chemical substances regulated 
under TSCA. 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. The following list of North American Industrial Classification 
System (NAICS) codes is not intended to be exhaustive, but rather 
provides a guide to help readers determine whether this document 
applies to them. Potentially affected entities may include:
     Petroleum Refineries (NAICS code 324110);
     Chemical Manufacturing (NAICS code 325);
     Unlaminated Plastics Film and Sheet (except Packaging) 
Manufacturing (NAICS code 326113);
     Unlaminated Plastics Profile Shape Manufacturing (NAICS 
code 326121);
     Plastics Pipe and Pipe Fitting Manufacturing (NAICS code 
326122);
     Laminated Plastics Plate, Sheet (except Packaging), and 
Shape Manufacturing (NAICS code 326130);
     Polystyrene Foam Product Manufacturing (NAICS code 
326140);
     Urethane and Other Foam Product (except Polystyrene) 
Manufacturing (NAICS code 326150);
     Plastics Bottle Manufacturing (NAICS code 326160);
     Plastics Plumbing Fixture Manufacturing (NAICS code 
326191);
     All Other Plastics Product Manufacturing (NAICS code 
326199);
     Tire Manufacturing (except Retreading) (NAICS code 
326211);
     Tire Retreading (NAICS code 326212);
     Rubber and Plastics Hoses and Belting Manufacturing (NAICS 
code 326220);
     Rubber Product Manufacturing for Mechanical Use (NAICS 
code 326291);
     All Other Rubber Product Manufacturing (NAICS code 
326299);
     Pottery, Ceramics, and Plumbing Fixture Manufacturing 
(NAICS code 327110);
     Clay Building Material and Refractories Manufacturing 
(NAICS code 327120);
     Flat Glass Manufacturing (NAICS code 327211);
     Other Pressed and Blown Glass and Glassware Manufacturing 
(NAICS code 327212);
     Glass Container Manufacturing (NAICS code 327213);
     Glass Product Manufacturing Made of Purchased Glass (NAICS 
code 327215);
     Cement Manufacturing (NAICS code 327310);
     Ready Mix Concrete Manufacturing (NAICS code 327320);
     Concrete Block and Brick Manufacturing (NAICS code 
327331);
     Concrete Pipe Manufacturing (NAICS code 327332); and
     Other Concrete Product Manufacturing (NAICS code 327390).
    If you have any questions regarding the applicability of this 
proposed action to a particular entity, consult the technical 
information contact listed under FOR FURTHER INFORMATION CONTACT.

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

    EPA is issuing this Notice of Proposed Rulemaking (NPRM) pursuant 
to the authority in TSCA section 6(b)(4) (15 U.S.C. 2605(b)(4)). EPA 
has inherent authority to reconsider previous decisions and to revise, 
replace, or repeal a decision to the extent permitted by law and 
supported by reasoned explanation. See FCC v. Fox Television Stations, 
Inc., 556 U.S. 502, 515 (2009); see also Motor Vehicle Mfrs. Assn v. 
State Farm Mutual Auto. Ins. Co., 463 U.S. 29, 42 (1983). See also the 
discussion in Units II.A. and B.

C. What action is the Agency taking?

    EPA is proposing to amend regulations that address how the Agency 
conducts risk evaluations on chemical

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substances under TSCA. These changes include, but are not limited to, 
targeted changes to certain definitions, clarifications regarding the 
required scope of risk evaluations, considerations related to peer 
review and the Agency's implementation of the scientific standards, the 
approach for risk determinations on chemical substances and 
considerations related to unreasonable risk, and the process for 
revisiting a completed risk evaluation. EPA is also proposing to amend 
the process and requirements for manufacturers making a voluntary 
request for an Agency-conducted risk evaluation on a particular 
chemical substance. EPA is requesting public comment on all aspects of 
this proposal.

D. Why is the Agency taking this action?

    As further explained in Units I., II., and III., EPA reexamined the 
July 20, 2017, final rule (Ref. 1) (hereinafter ``2017 final rule'') 
that established procedures and requirements for chemical risk 
evaluation under TSCA, in consideration of:
     The statutory text and structure and Congressional intent.
     The November 14, 2019, opinion issued by U.S. Court of 
Appeals for the Ninth Circuit in response to petitions for judicial 
review, consolidated under Safer Chemicals, Healthy Families v. USEPA 
(Ref. 2), of the 2017 final rule and related court orders.
     Executive Order 13990, Protecting Public Health and the 
Environment and Restoring Science to Tackle the Climate Crisis (Ref. 
3).
     Lessons learned from the Agency's implementation of the 
risk evaluation program to date including feedback from the National 
Academies of Science Engineering and Medicine and scientific peer 
reviewers.
    As a result of this reexamination, the Agency is proposing targeted 
amendments of the 2017 final rule.

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

    The incremental impacts of this action are associated with 
procedural requirements, as described in Unit III.K., which apply to 
manufacturers when manufacturers (including importers) elect to request 
that EPA perform a risk evaluation on a particular chemical substance. 
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. These estimates of 
burden and costs are available in the docket, and are discussed in Unit 
V. and briefly summarized here (Ref. 4).
    The total estimated annual burden is 166 hours and $115,711 (per 
year), which is based on an estimated per request burden of 166 hours.
    In addition, EPA's evaluation of the potential costs associated 
with this action is discussed in Unit VI.B. Since this rulemaking 
focuses on the activities that a manufacturer must perform, the 
estimated incremental costs to the public are expected to be 
negligible. EPA requests specific comment on the burden estimate and 
assumptions associated with the calculation associated with the burden 
(e.g., number of requests EPA expects).

F. What should I consider as I prepare my comments for EPA?

1. Submitting CBI
    Do not submit CBI to EPA through https://www.regulations.gov or 
email. If you wish to include CBI in your comment, please follow the 
applicable instructions at https://www.epa.gov/dockets/commenting-epa-dockets#rules and clearly mark the part or all of the information that 
you claim to be CBI. In addition to one complete version of the comment 
that includes information claimed as CBI, a copy of the comment that 
does not contain the information claimed as CBI must be submitted for 
inclusion in the public docket. Information so marked will not be 
disclosed except in accordance with procedures set forth in 40 CFR part 
2.
2. Tips for Preparing Your Comments
    When preparing and submitting your comments, see the commenting 
tips at https://www.epa.gov/dockets/commenting-epa-dockets.html.

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 risk evaluation, the development of 
criteria for manufacturer-requested risk 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 
EPA to consider reasonably available information and 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)).

B. Judicial Review of the 2017 Final Rule

    In the preamble of the 2017 final rule, EPA explained that it 
interpreted the requirements of TSCA section 6 to apply to conditions 
of use for which manufacturing, processing, or distribution in commerce 
is intended, known to be occurring, or reasonably foreseen to occur, 
rather than to legacy uses, which EPA used as a term for continuing, 
in-situ uses of chemicals for which manufacturing, processing, or 
distribution in commerce had ceased (e.g., certain phased-out flame 
retardants present in textiles or furniture that continue to be used, 
asbestos-containing pipe wrap, etc.), or associated disposal. In 
addition, among other regulatory provisions, the 2017 final rule 
established that the submission of inaccurate, incomplete, or 
misleading information pursuant to a manufacturer-requested risk 
evaluation is a prohibited act subject to penalties under title 18 of 
the U.S. Code. The 2017 final rule also established requirements for 
information that must be submitted by a manufacturer when requesting 
that EPA conduct a risk evaluation (40 CFR 702.37(b)(4)) and that the 
submitted information be held to the scientific standards established 
in TSCA section 26(h) (40 CFR 702.37(b)(6)).
    Several non-governmental organizations filed petitions for judicial 
review of the 2017 final rule, which were consolidated in the U.S. 
Court of Appeals for the Ninth Circuit (hereafter, the ``Ninth 
Circuit'') under Safer Chemicals, Healthy Families v. USEPA, on August 
10, 2017 (Ref. 2). The Ninth Circuit issued its opinion on November 14, 
2019, holding that the EPA unlawfully excluded ``legacy uses and 
associated disposals'' from the conditions of use that the agency would 
consider in any risk evaluation (Ref. 2). Also, at the Agency's 
request, the Ninth Circuit (1) vacated and remanded the rule provisions 
applying criminal penalties to the submission of inaccurate or 
incomplete information to

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EPA pursuant to a manufacturer-requested risk evaluation, and (2) 
remanded without vacatur the rule provisions addressing the information 
requirements for, and application of the TSCA section 26 scientific 
standards to, a manufacturer-requested risk evaluation (Ref. 5).
    The Court declined to rule on several other aspects of the 
challenge, including that the rule suggested EPA would make risk 
determinations on individual uses of a chemical instead of on the 
chemical itself, and statements in the preamble regarding broad 
discretion to choose to exclude conditions of use from the scope of the 
risk evaluations. The Court reasoned that petitioners' claim that EPA 
would make risk determinations on individual uses instead of on the 
chemical itself as the law required was not justiciable due to 
ambiguity in the 2017 final rule text. The Court noted it was unclear 
``whether the Agency will actually conduct risk evaluations in the 
manner [those litigants] fear[ed]'' and that the claim was therefore 
not justiciable (Ref. 2). With regard to petitioners' claim that EPA 
intended to exclude conditions of use out of the scope of the risk 
evaluations, the court held that claim not ripe, but noted that it did 
``not interpret the language in the [2017 final rule] to say anything 
about exclusion of conditions of use'' (Ref. 2).

C. Review of the 2017 Final Rule Under Executive Order 13990

    Executive Order 13990 instructs that the Federal Government be 
guided by the best science and be protected by processes that ensure 
the integrity of Federal decision-making, and established the 
Administration's policy of, among other concerns, following the 
science, improving public health and protecting the environment, 
limiting exposure to dangerous chemicals, reducing greenhouse gas 
emissions, and prioritizing environmental justice (EJ) when delivering 
on these concerns. Executive Order 13990 also instructs agencies to (1) 
review actions issued between January 20, 2017, and January 20, 2021, 
that may be inconsistent with or present obstacles to implementing the 
policy established in the order and, (2) consider suspending, revising, 
or rescinding such actions. Also on January 20, 2021, the Biden-Harris 
Administration issued a list of specific actions to be reviewed in 
accordance with Executive Order 13990 that included the 2017 final rule 
(Ref. 6).
    EPA announced certain policy changes for TSCA risk evaluations on 
June 30, 2021 (Ref. 7) to ensure that risk evaluations follow the 
science and the law, including:
1. Expanded Consideration of Exposure Pathways
    Prior to June 30, 2021, the first 10 risk evaluations did not 
consistently assess air, water or disposal exposures to the general 
population based on an argument that these exposure pathways were 
already regulated, or could be regulated, under other statutes 
administered by EPA, such as the Clean Air Act, Safe Drinking Water 
Act, Clean Water Act, Resource Conservation and Recovery Act, or 
Comprehensive Environmental Response, Compensation, and Liability Act. 
The approach to exclude certain exposure pathways conflicted with the 
plain language of the law to evaluate chemical substances under the 
known, intended or reasonably foreseen circumstances associated with 
the full lifecycle of the chemical substance. It prevented 
consideration of relevant exposure information (e.g., information 
indicating presence of the chemical in air or water) in spite of 
statutory requirements that the Agency base its decisions on the best 
available science. The approach also resulted in a failure to 
consistently and comprehensively address potential exposures to the 
general population, as well as to certain potentially exposed or 
susceptible subpopulations. EPA announced it would no longer exclude 
consideration of such exposure pathways from TSCA risk evaluations.
2. Assumptions About Use of Personal Protective Equipment (PPE)
    Prior to June 30, 2021, EPA's TSCA risk evaluations generally 
assumed that workers were always provided and appropriately used PPE. 
However, as described in Unit III.G.1., data on violations of PPE use 
suggest that assumptions that PPE is always provided to workers, worn 
properly, and effective at eliminating exposures are not justified. In 
addition, TSCA requires that risk evaluations consider the known, 
intended or reasonably foreseen circumstances associated with the 
chemicals substance--including circumstances that result or could 
result in exposures to workers. For the reasons described further in 
Unit III.E.1., EPA believes that circumstances that result in 
occupational exposures to chemicals are reasonable to foresee, and, in 
many cases, known. As such, continued application of this general 
assumption could result in risk evaluations that underestimate risks, 
and in turn, prevent risk management rules from affording necessary 
protections. EPA announced that it would no longer assume that PPE is 
always used in occupational settings when making unreasonable risk 
determinations for a chemical.
3. ``Whole Chemical'' Risk Determination Approach
    Prior to June 30, 2021, EPA made separate unreasonable risk 
determinations for each condition of use identified in the risk 
evaluation scope. EPA announced that, going forward, it would make the 
determination of unreasonable risk on ``the chemical substance,'' 
rather than for each individual condition of use in isolation. As 
described further in Unit III.F.1., doing so going forward better 
aligns with the statute and Congress' intent, and enables the Agency's 
risk determinations to better reflect the potential for combined 
exposures across multiple conditions of use.
    EPA invites public comment on the adoption of these changes in the 
amended procedural rule.

D. Agency Implementation

    Since the 2017 final rule, EPA has finalized ten chemical risk 
evaluations under TSCA and published a draft supplement to the risk 
evaluation for 1,4-Dioxane. Additionally underway are 20 more risk 
evaluations on high-priority substances, a part 2 of the asbestos risk 
evaluation that will cover additional fiber types and ``legacy'' 
conditions of use, and several manufacturer-requested risk evaluations 
(Ref. 8). EPA is also developing a number of rulemakings to address 
unreasonable risks identified in these risk evaluations. The Agency has 
gained valuable experience in carrying out these actions and received a 
wealth of feedback on our procedures from public commenters and through 
scientific peer review. The proposed rule reflects lessons learned, 
efforts to increase efficiencies, and includes improvements to the 
process and requirements for manufacturer-requested risk evaluations 
that are more consistent with Agency scientific practices and policies. 
The proposed rule also includes some structural and substantive 
revisions for greater clarity and readability, and, more generally, to 
enhance the public's understanding of how EPA expects to carry out TSCA 
risk evaluations.
    EPA intends that the provisions of this rulemaking be severable. In 
the event that any individual provision or part of this rulemaking is 
invalidated, EPA intends that this would not render the entire 
rulemaking invalid, and that any individual provisions that can 
continue to operate will be left in place.

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III. Proposed Amendments

A. Policy Objectives

    The risk evaluation process established in 40 CFR part 702, subpart 
B outlines how EPA will determine, pursuant to TSCA section 6(b)(4)(A), 
whether a chemical substance presents an unreasonable risk of injury to 
health or the environment. EPA's general objectives for the proposed 
amendments, in keeping with the considerations addressed in Unit II, 
are to (1) better align the TSCA risk evaluation process with the 
statutory text and structure and Congressional intent, (2) ensure that 
the risk evaluation process under TSCA is consistent with the best 
available science and based on the weight of the scientific evidence, 
maintains the integrity of Federal decision-making, and upholds the 
policy in various Executive orders, (3) address the outcome of the 
Ninth Circuit litigation on the 2017 final rule, (4) apply lessons 
learned to date to improve the Agency's processes moving forward, and 
(5) enhance the public's understanding of how EPA expects to carry out 
subsequent TSCA risk evaluations. Through improvements to the risk 
evaluation process in these proposed amendments, EPA anticipates that 
any risk management actions following any determination that a chemical 
substance presents unreasonable risk will result in needed public 
health and environmental protections that limit exposure to dangerous 
chemicals, and, where applicable, address the climate crisis and 
advance environmental justice.
    To accomplish these objectives, EPA is proposing targeted changes 
and clarifying edits to the existing process by which the Agency 
evaluates risk from chemical substances for purposes of TSCA section 6. 
Additionally, this proposal includes structural changes to the 
regulatory text to accomplish these goals. EPA is not proposing to 
establish 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 proposed rule seeks to 
ensure that the risk evaluation process is transparent, without unduly 
restricting the science that will be used to conduct the evaluations, 
allowing the Agency flexibility to adapt and keep pace with changing 
science as it conducts TSCA risk evaluations into the future.

B. General Provisions

1. Applicability of Updated Procedures
    EPA is proposing that the changes to the procedures as part of this 
rulemaking would be applied to all risk evaluations initiated on or 
after the date of the final rule. For risk evaluations in process as of 
the date of the final rule, EPA would expect to apply the proposed 
changes to those risk evaluations only to the extent practicable, 
taking into consideration the statutory requirements and deadlines. 
Where a change to a risk evaluation would prevent the Agency from 
meeting the statutory deadline, for example, EPA would generally not 
view that change as practicable. However, where applying a proposed 
change would impact timeliness but also ensure compliance with other 
statutory obligations (e.g., conducting an appropriately scoped risk 
evaluation), EPA would make a judgment on practicability by weighing 
the implications for public health and environment, defensibility from 
both a scientific and legal perspective, Agency priorities and the 
availability of resources. As a general matter, EPA believes that most 
of its ongoing risk evaluations, including the ongoing supplement to 
the 1,4-Dioxane risk evaluation and part two of the Asbestos risk 
evaluation, will likely conform to the changes contemplated in this 
NPRM, and does not anticipate significant challenges in this area. 
Finally, EPA does not expect to apply these procedures retroactively to 
risk evaluations already completed.
2. Categories of Chemical Substances
    EPA is proposing to clarify the regulations with respect to their 
applicability to risk evaluations on categories of chemical substances. 
Pursuant to TSCA section 26(c), wherever TSCA requires or authorizes 
EPA to take action on a chemical substance, EPA can take that same 
action with respect to a category of chemical substances (i.e., 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's procedural requirements generally refer to 
``chemicals'' or ``chemical substances,'' EPA is proposing to clarify 
in the regulatory text at Sec.  702.31(d) that those references also 
apply to categories of chemical substances.

C. Definitions

    EPA is proposing changes to a number of definitions codified in the 
existing regulatory text. EPA is proposing to eliminate the codified 
definitions for ``best available science'' and ``weight of scientific 
evidence.'' As described in greater detail in Unit III.I., EPA believes 
that defining these concepts in the rulemaking is both unnecessary and 
inhibits the Agency's flexibility to quickly adapt to and implement 
changing science. Not codifying regulatory definitions of these 
scientific terms is consistent with the approach in the 2017 proposed 
rule (Ref. 9) (hereinafter ``2017 proposed rule'') and was supported by 
public comment. Instead, as described in Unit III.I. EPA intends to 
ensure that its risk evaluations are consistent with Agency guidance 
and methodologies in applying these terms. As TSCA requires, at 15 
U.S.C. 2625(h), EPA's risk evaluations will continue to use scientific 
information, technical procedures, measures, methods, protocols, 
methodologies, or models, employed in a manner consistent with the best 
available science. Further, both risk evaluation and risk management 
decisions under TSCA section 6 will be based on the weight of the 
scientific evidence, as required by 15 U.S.C. 2625(i). EPA's expected 
application of these terms is more fully described in Unit III.G. 
regarding Risk Evaluation Considerations.
    Second, and as described further in Unit III.G.4., EPA is proposing 
an addition to the examples identified in the definition of 
``potentially exposed or susceptible subpopulation'' which currently 
include ``infants, children, pregnant women, workers, or the elderly.'' 
The Agency proposes to add ``overburdened communities'' to better 
reflect the Agency's intent to consider risks to particular communities 
in the United States that potentially experience disproportionate 
environmental harms and risks, while also ensuring environmental 
justice--the fair treatment and meaningful involvement of all people 
regardless of race, color, culture, national origin, income, and 
educational levels with respect to the development, implementation, and 
enforcement of protective environmental laws, regulations, and 
policies--is considered where appropriate, including as part of any 
subsequent risk management action.
    Finally, EPA is proposing minor updates to a number of other 
definitions to better align with existing Agency guidance. 
Specifically, the definitions for ``pathways'' and ``routes'' have been

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adjusted for consistency with EPA's Exposure Factors Handbook (Ref. 
10). Additionally, EPA is also proposing clarifying edits to the 
definitions for ``aggregate exposure'' and ``sentinel exposure'' to 
align with Agency guidance, and to make clear that the terms can apply 
not only to individual persons, but to the populations and environment 
when doing so is consistent with the best available science. EPA is not 
proposing to amend the definitions for ``act,'' ``conditions of use,'' 
``reasonably available information,'' ``sentinel exposure,'' 
``uncertainty,'' or ``variability.''

D. Technical Corrections and Reorganization

    The proposed rule reflects a number of minor updates and 
corrections and general organizational restructuring. For example, 
references to 15 U.S.C. 2605(b)(2)(A) have been removed in light of the 
fact that the law's one-time requirement related to identification of 
the first group of 10 chemicals for risk evaluation has been satisfied 
and is no longer applicable for purposes of the procedural rule. 
Additionally, EPA made minor updates to the regulatory text to correct 
typos and to ensure consistency in use of certain phrases (e.g., 
manufacturer-requested risk evaluations). More generally, EPA aimed to 
improve the readability of certain provisions, and, ultimately, enhance 
the public's ability to understand how EPA will undertake TSCA risk 
evaluations. As part of this effort, EPA is proposing to reorganize the 
sequence and structure of regulatory provisions to, for example, 
establish sections that distinguish between the components of the risk 
evaluation, the analytic considerations to be applied in the risk 
evaluation, and the associated procedural timeframes and actions. EPA 
welcomes comment on these changes to enhance clarity and readability. 
EPA has provided a short description of the reorganization:
     Proposed Sec. Sec.  702.31, 702.33, and 702.35 have 
retained the same organization.
     Proposed Sec.  702.37 ``Evaluation requirements'' includes 
many of the components of Sec.  702.41 of the 2017 final rule, 
including statutory requirements of a risk evaluation, upholding the 
science requirements of section 26(h), inclusion of conditions of use, 
and clarity regarding making an unreasonable risk determination on the 
chemical substance. This section also includes EPA's approach to 
information and information sources, much of which is moved from Sec.  
702.41(b) in the 2017 final rule. New proposed language included in 
this proposed section is EPA's approach to conducting a fit-for-purpose 
risk evaluation, addressing information gaps, and use of data gathering 
authorities.
     Proposed Sec.  702.39 is a newly titled section 
``Components of risk evaluation'' that is composed of 2017 final rule 
Sec. Sec.  702.41, 702.43, 702.45. This one section includes the 
components of a risk evaluation (e.g., scope, hazard assessment, 
exposure assessment, risk characterization, risk determination) and 
what they must contain. Some of the specific requirements of the hazard 
and exposures assessment have been streamlined and reconfigured from 
the 2017 final rule.
     Proposed Sec.  702.41 ``Peer review'' was Sec.  702.47 in 
the 2017 final rule.
     Proposed Sec.  702.43 contains the parts of a risk 
evaluation (e.g., draft scope, final scope, draft risk evaluation and 
final risk evaluation) and the process and timelines associated with 
the development and publication of these parts. Much of this section 
was moved from the 2017 final rule Sec.  702.41. This proposed section 
now includes provisions pertaining to substantive revisions to these 
documents post publication.
     Proposed Sec.  702.45 is the revised process for 
submitting a manufacturer requested risk evaluation, moved from the 
2017 final rule 702.37.
     Proposed Sec.  702.47 ``Interagency collaboration'' 
remains unchanged from 2017 final rule Sec.  702.39. As part of EPA's 
commitment to identify information earlier in the prioritization and 
risk evaluation processes, the Agency expects to continue to engage and 
enhance coordination with other Federal agencies that may have 
chemical-specific information. Doing so will not only serve to inform 
the Agency's work in the risk evaluation, but can also help to 
proactively identify conditions of use that may be essential to 
national security, critical infrastructure, and/or mission critical 
uses, identify existing safety measures Federal agencies already have 
in place for their uses, and inform any subsequent risk management 
approaches.
     Proposed Sec.  702.49 ``Publicly available information'' 
remains substantively unchanged from Sec.  702.51 from the 2017 final 
rule.

E. Scope of TSCA Risk Evaluations

1. Inclusion of All Conditions of Use
    EPA is proposing a number of changes to the regulatory text to make 
clear that the scope of TSCA risk evaluations will not exclude any 
``conditions of use'' (i.e., any circumstance, based on reasonably 
available information, under which a chemical substance is known, 
intended or reasonably foreseen to be manufactured, processed, 
distributed in commerce, used, or disposed of) to better align with the 
statutory text and structure, including modification to various 
provisions in the current rule that state or imply that EPA has broad 
discretion to choose which conditions of use it will or will not 
evaluate. These proposed amendments are intended to ensure that the 
scopes of future risk evaluations are determined in accordance with the 
law.
    When TSCA was originally signed into law in 1976, there were tens 
of thousands of chemicals in commerce and the law imposed no mandate 
that EPA conduct any assessments to determine whether those existing 
chemicals present unreasonable risk of injury to health or the 
environment. While EPA did conduct some risk assessments on a handful 
of these existing chemicals prior to 2016, those assessments were 
focused on a specific subset of individual conditions of use of 
chemicals (e.g., paint and coating removal, vapor degreasing, etc.). 
The net effect of this use-by-use approach was that--even if EPA were 
to identify risks through a risk assessment and successfully promulgate 
a rule under TSCA to manage those particular risks--the public would 
still not have certainty regarding risks from the full spectrum of uses 
of the chemical substance. This uncertainty, in turn, would continue to 
erode public confidence in the safety of chemicals pervasive in our 
households, communities and the environment, and encourage states to 
adopt an increasingly complex patchwork of regulatory measures to 
address chemical risks.
    One of the defining features of the 2016 amendments to TSCA was the 
mandate for EPA to systematically prioritize those thousands of 
existing chemicals for review, and then to evaluate their risks, 
holistically, under the chemical's ``conditions of use''--a phrase that 
Congress defined to capture a chemical's full lifecycle, i.e., ``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 clearly a significant undertaking, 
Congress recognized that comprehensive progress on evaluating the 
universe of thousands of existing chemicals would not be made without 
this mandate, coupled with a strong risk-based safety standard and 
deadlines

[[Page 74297]]

for completing the work (Ref. 11). To allow EPA to continue to address 
only a subset of each chemical's uses as part of the new TSCA process 
would deny such comprehensive progress.
    The question of whether the Agency has broad discretion under the 
law to exclude conditions of use from the scope of risk evaluations was 
the source of much discussion publicly during the development of the 
2017 proposed and final rules. EPA believes the approach proposed 
herein is more consistent with congressional intent and reflects 
consensus of technical discussion with congressional negotiators 
leading up to the passage of the 2016 amendments. See also Ref. 11 at 
p. S3516 (implying the lack of discretion in the ``mandate to consider 
conditions of use'') and p. S3519 (referencing the prior TSCA risk 
assessments that did not consider ``all conditions of use'' and 
Congress' desire to nonetheless allow EPA to proceed with risk 
management based on those select ``partial'' risk evaluations). 
However, in the preamble to the 2017 final rule the Agency asserted 
that it retained discretion to exclude conditions of use from the scope 
of TSCA risk evaluations. Ref. 1 at p. 33729.
    In support of this assertion of discretionary scoping authority in 
the 2017 final rule, EPA pointed to language in TSCA section 6(b)(4)(D) 
that requires EPA to identify the conditions of use in a scope document 
that the Agency ``expects to consider'' in a risk evaluation and the 
``as determined by the Administrator'' phrasing in the statutory 
definition of ``conditions of use'' itself (Ref. 1 at p. 33729). EPA 
argued that such language gave the Agency discretion to select among 
the conditions of use and, ultimately, to exclude conditions of use 
from the scope of TSCA risk evaluations. EPA expressed at that time 
that those provisions empowered the Agency to exclude, for example, 
conditions of use that the Agency deemed ``de minimis'' in nature, or 
conditions of use where opportunities for exposure were likely to be 
limited (e.g., closed system or intermediate) (Ref. 1 at p. 33729). As 
discussed further in Unit III.E.3., EPA has also relied on this 
interpretation to exclude consideration of exposure pathways in TSCA 
risk evaluations where EPA or another regulatory agency had or could 
assess and regulate the same chemical--a policy that excluded exposures 
to the general population through air, water and disposal, and left 
potential risks unaccounted for.
    Upon further review, and as described in the preamble to the 2017 
proposed rule and supported by legislative history, EPA believes that 
the better reading of TSCA's statutory text and structure is that EPA 
does not have discretionary scoping authority, and that risk 
evaluations are to be conducted on the circumstances under which the 
chemical is known, intended and reasonably foreseen to be manufactured, 
processed, distributed in commerce, used, and disposed of (i.e., 
activities that constitute the ``conditions of use'' within the meaning 
of TSCA section 3(4)) (15 U.S.C. 2602(4)). The plain language of TSCA 
section 6(b)(4)(A) specifies that EPA must determine in a risk 
evaluation whether ``a chemical substance'' presents an unreasonable 
risk of injury to health or the environment ``under the conditions of 
use.'' Similar language appears throughout section 6 of the law. See, 
for example, 15 U.S.C. 2605(b)(4)(G)(i) and (ii) stating that the risk 
evaluation ``for a chemical substance'' must be completed within 3 to 
3.5 years of initiation. As such, while EPA at one time interpreted the 
statue to permit a different approach, the statute is better 
interpreted as requiring that the evaluation must be on the chemical 
substance--not a subset of individual conditions of use of the chemical 
substance. EPA also believes the purpose of the requirement to evaluate 
the ``chemical substance'' was to ensure that the Agency, through the 
risk evaluation process, would comprehensively determine whether a 
chemical substance, under the known, intended, and reasonably foreseen 
circumstances of manufacture, processing, distribution in commerce, use 
and disposal, presents an unreasonable risk. This reading also aligns 
with the requirements under the 2016 TSCA amendments to establish a 
constant pipeline of activity on assessing chemical substances and 
managing risks, effectively driving forward progress on the tens of 
thousands of unreviewed existing chemical substances in commerce (15 
U.S.C. 2605(b)(2) and (b)(3)(C)). In the absence of comprehensive risk 
evaluations on chemical substances (i.e., an approach that considered 
only a subset of a chemical's uses), the unevaluated uses would create 
uncertainty as to whether EPA had fully addressed a chemical's 
unreasonable risk and further delay progress on the backlog of existing 
chemicals.
    Given these considerations, EPA believes that the phrase ``as 
determined by the Administrator'' in the statutory definition of 
``conditions of use'' requires application of fact and professional 
judgment in determining whether or not a particular circumstance is 
known, intended or reasonably foreseen--and should not be viewed as 
license to select among those circumstances in determining which should 
be included or excluded from the scope of a risk evaluation that is to 
be completed on a chemical substance (15 U.S.C. 2602(4)). Likewise, the 
instruction in TSCA section 6(b)(4)(D) for the Agency to--during the 
scoping phase--identify the conditions of use it ``expects to 
consider'' in a risk evaluation, is best read as directing the Agency 
to identify the uses and other activities that it has determined 
constitute the conditions of use of the chemical substance, while 
acknowledging that the Agency's expectations at the scoping phase may 
not always align perfectly with the conditions of use actually 
considered and assessed in draft and final risk evaluations. EPA may, 
for example, mistakenly identify a condition of use in the scope 
document, and later remove it from analysis in the risk evaluation. 
Alternatively, EPA might be unaware of or inadvertently exclude a 
condition of use during the scoping phase, but later incorporate it 
into its risk evaluation. While EPA at one time interpreted the 
language differently, EPA no longer believes that the ``expects to 
consider'' language in TSCA section 6(b)(4)(D) gives the Agency broad 
discretion to choose among conditions of use that it will include in a 
risk evaluation of a chemical substance. The Ninth Circuit agreed with 
this view, noting that the phrase ``conditions of use that the EPA 
plans to consider'' in the 2017 final rule and the similar phrase 
``expects to consider'' in TSCA section 6(b)(4)(D) simply refer to the 
Agency's role in determining what the conditions of use are for a 
particular substance, and do not grant EPA discretion to exclude 
conditions of use from the scope of a risk evaluation (Ref. 2).
    Consideration of all conditions of use in TSCA risk evaluations is 
also necessary from a scientific perspective to ensure development of a 
technically sound determination as to whether a chemical substance 
presents an unreasonable risk of injury to health or the environment. 
Thus, consideration of all conditions of use ensures risk evaluations 
are consistent with the best available science and based on the weight 
of scientific evidence (15 U.S.C. 2625(h) and (i)). As discussed 
further in Unit III.G.2., there may be situations where certain 
conditions of use are associated with relatively lower exposures, but 
nonetheless in the aggregate those uses may contribute to

[[Page 74298]]

unreasonable risk. Exclusion of conditions of use from risk 
evaluations--irrespective of the Agency's intention in so doing--
deprives the public of a complete picture of the chemical's risk, and 
may leave significant risk to human health or the environment 
unaccounted for and ultimately unaddressed.
    For these reasons, the proposed rule clarifies that EPA will not 
exclude conditions of use (i.e., any circumstances under which the 
chemical is known, intended or reasonably foreseen to be manufactured, 
processed, distributed in commerce, used or disposed of) from the scope 
of a risk evaluation by amending the regulatory text where it was 
either stated or implied that the Agency had broad discretion to 
exclude certain conditions of use from analysis.
2. Determination of ``Conditions of Use''
    Although EPA no longer interprets TSCA to allow the Agency to 
exclude any intended, known or reasonably foreseen conditions of use 
from the scope of a risk evaluation, EPA nonetheless retains authority 
to exercise judgment in making its determination as to whether a 
particular circumstance is intended, known, or reasonably foreseen, and 
therefore falls within the definition of ``condition of use'' for a 
particular chemical. As such, for each risk evaluation, EPA has and 
will continue to undergo a process to determine each chemical's 
conditions of use, analyzing reasonably available information and 
applying the facts, Agency expertise and professional judgment on a 
case-by-case basis. As described previously, the phrase ``as determined 
by the Administrator'' in the statutory definition of ``conditions of 
use'' requires EPA to review the reasonably available information and 
exercise judgment in determining whether a particular circumstance is 
intended, known or reasonably foreseen. For example, when information 
suggests that a circumstance of manufacture, processing, distribution 
in commerce, use or disposal is known to be occurring, EPA will 
determine that known circumstance to be a condition of use and include 
it within the scope of the risk evaluation, irrespective of other 
factors like the likelihood of that particular condition of use to be a 
significant contributor to risk. Likewise, where, in the Agency's 
professional judgment, a circumstance is reasonably foreseen to occur 
in the future, EPA will determine that circumstance to be a condition 
of use and include it within the scope of the risk evaluation, even 
where that condition of use may not contribute significantly to the 
Agency's ultimate conclusions on risk.
    In the preamble to the 2017 final rule (Ref. 1) EPA identified 
legacy disposal as falling outside the definition of ``conditions of 
use.'' EPA interpreted the TSCA definition for ``conditions of use'' as 
focusing on circumstances that are prospective or on-going, rather than 
reaching back to evaluate risks associated with legacy disposal (i.e., 
disposal that has already occurred) (Ref. 1 at p. 33730). The Ninth 
Circuit agreed, holding that TSCA unambiguously does not require legacy 
disposals to be considered as conditions of use (Ref. 2 at pp. 425-
426). The Court reasoned that a substance that has already been 
disposed of will not ordinarily be intended, known, or reasonably 
foreseen to be prospectively manufactured, processed, distributed in 
commerce, used, or disposed of again (Ref. 2). EPA is not reconsidering 
that issue in this proposal. However, EPA generally does not view any 
other categorical exclusions from the definition of condition of use as 
appropriate.
    With respect to legacy use and associated disposal, however, EPA 
now believes that such circumstances are, in fact, ``conditions of 
use'' and must be considered in risk evaluations. (Ref. 2, pp. 420-
421). An example would be in-situ asbestos insulation, a product no 
longer manufactured but nevertheless an ongoing downstream use. Future 
disposal of asbestos insulation is clearly an example of a chemical 
substance being ``disposed of'' and to the extent it is ``intended'' 
that such a substance be disposed of, or ``known'' that it will be, or 
if such disposal is ``reasonably foreseen,'' that circumstance 
unambiguously falls within TSCA's definition of ``conditions of use.'' 
(Ref. 2, pp. 420-421). As such, EPA is already developing a ``part 2'' 
of the TSCA risk evaluation for asbestos in order to include analysis 
of exposures and potential risks from legacy uses and expects future 
risk evaluations to also consider legacy uses and associated disposals 
as conditions of use (i.e., circumstances associated with ``use'' and 
``disposal''). EPA believes that this approach is consistent with the 
statutory text and structure, as well as Congressional intent.
    There are other categories of circumstances that EPA intends to 
consider in future risk evaluations associated with conditions of use 
that also bear mention. The known, intended, and reasonably foreseen 
production of a chemical as a byproduct or the known presence of a 
chemical as an impurity or within an article, for example, are squarely 
``conditions of use'' that generally must be included within the scope 
of risk evaluations.
    Likewise, where EPA has reasonably available information 
demonstrating that certain exposures associated with a spill or leak 
are known or reasonably foreseen to occur during a condition of use 
that is part of a risk evaluation (e.g., regular or predictable 
exposures from equipment leaks as part of the manufacturing process), 
EPA would expect to include that exposure within the scope of the risk 
evaluation. However, EPA would not expect to include within the scope 
of the risk evaluation exposures from releases of a chemical substance 
that are unsubstantiated, speculative or otherwise not likely to occur. 
For example, a future one-time accident involving the chemical 
substance that could be caused by an atypical one-time set of 
circumstances would generally not be assessed as part of a risk 
evaluation. Additionally, EPA would generally not include within the 
scope of the risk evaluation exposures associated with future extreme 
weather events (e.g., hurricanes and wildfires). However, if 
information reasonably available to the Agency indicated that factors 
such as rising sea levels or extreme temperatures made worse by climate 
change were leading to regular and predictable changes in exposures 
associated with a given condition of use of a chemical substance, EPA 
would expect to consider those exposures within the scope of the risk 
evaluation. EPA requests comment on alternative proposals for 
considering potential climate-related risks. As discussed further in 
Units III.E.4. and III.I.2., EPA may adjust the level of refinement for 
a particular exposure assessment by conducting a ``fit-for-purpose'' 
assessment. While EPA will always apply the scientific standards 
required under TSCA, the depth or extent of analysis will be 
commensurate with the nature and significance of the decision. For 
example, EPA may find that the types of exposures described in this 
paragraph warrant consideration as part of an exposure assessment, 
either in a qualitative or a quantitative exposure assessment. 
Additionally, the Agency will decide the level of analysis warranted 
based on a number of factors, including but not limited to: the 
substance's physical-chemical properties; environmental fate and 
transport properties; the likely duration, intensity, frequency, and 
number of exposures under the condition of use; reasonably available 
information about the release; and other relevant considerations.

[[Page 74299]]

    Even where a condition of use is not expected to be a significant 
contributor to risk from a particular chemical, TSCA nonetheless 
requires EPA to include it in the scope of the risk evaluation. 
However, and as described in Unit III.E.4., EPA has discretion to 
conduct its evaluations in a fit-for-purpose manner, which may justify 
tailoring the level of analyses to focus more detailed--and therefore 
more time and resource intensive--quantitative efforts on the 
conditions of use that pose the greatest potential for exposure and 
therefore risk.
3. Inclusion of All Exposure Pathways
    In carrying out the first ten risk evaluations under TSCA, EPA 
narrowed the scope of those evaluations by excluding analysis of 
certain exposures to the general population from releases to air, water 
and land. The approach, which was not contemplated in the procedural 
framework rule but was first articulated in ``Problem Formulation'' 
documents published in 2018 (after the Final Scope documents) for each 
of the first ten chemicals undergoing risk evaluation, was premised on 
an argument that those pathways were already adequately assessed and 
managed--or could theoretically in the future be assessed and managed--
under other EPA statutes and regulatory programs (Ref. 12). EPA further 
stated at that time that its intention was to use Agency resources 
efficiently under the TSCA program, avoid duplicating efforts taken 
pursuant to other Agency programs, maximize scientific and analytical 
efforts, and meet TSCA's statutory deadline for completing risk 
evaluations. In the final risk evaluations for the first ten chemicals, 
EPA excluded exposure pathways that could be covered by regulatory 
programs under the Clean Air Act (CAA), Clean Water Act (CWA), Safe 
Drinking Water Act (SDWA), Resource Conservation and Recovery Act 
(RCRA), and Comprehensive Environmental Response, Compensation, and 
Liability Act (CERCLA) (e.g., drinking water pathways covered under the 
SDWA due to the existence of National Primary Drinking Water 
Regulations (NPDWRs) with chemical-specific, enforceable Maximum 
Contaminant Levels (MCL), or the inclusion of the chemical as an 
unregulated chemical on the Candidate Contaminant List (CCL)). EPA 
further asserted that this approach was supported by several TSCA 
authorities, including TSCA section 6(b)(4)(D), which gives the Agency 
authority to include the conditions of use that the Administrator 
``expects to consider'' and section 9(b)(1), which allows Administrator 
to use other EPA administered statutes, if the Administrator determines 
there is risk to health or the environment (Ref. 13).
    This approach was criticized by the Science Advisory Committee on 
Chemicals (SACC), public commenters, and others (Ref. 14, 15, 16). As 
announced on June 30, 2021, EPA will no longer follow the approach and 
no longer intends to apply it to risk evaluations. Additionally, the 
Agency applied the Draft TSCA Screening Level Approach for Assessing 
Ambient Air and Water Exposures to Fenceline Communities Version 1.0 
(Ref. 17) and additional feedback from peer review and public comment 
in order to consider whether its past failure to have assessed the 
risks associated with these exposures--along with its application of 
other past policies and interpretations--may have resulted in 
unaccounted potential risks. EPA has reconsidered the text of the 
relevant statutory provisions, overarching statutory structure and 
context, and legislative history, and no longer interprets the law to 
authorize exclusion of exposure pathways from the scope of TSCA risk 
evaluations because other EPA offices have already or could in the 
future regulate those chemicals. EPA's prior interpretation in support 
of that approach was premised in large part on the Agency's 
interpretation of TSCA section 6(b)(4)(D) as providing the 
discretionary authority to tailor the scope of exposures evaluated in 
TSCA risk evaluations. See, e.g., Risk Evaluation for Methylene 
Chloride, sec. 1.4.2 (Ref. 13). For the reasons explained in Unit 
III.B., EPA no longer interprets TSCA section 6(b)(4)(D) to provide 
broad discretionary authority to exclude conditions of use or exposure 
pathways from the scope of TSCA risk evaluations.
    EPA also cited TSCA section 9(b)(1) as support for its approach, 
asserting that the instruction in that provision for the Administrator 
to ``coordinate actions taken under [TSCA] with actions taken under 
other Federal laws administered [by EPA]'' provided a broad, 
freestanding authority to exclude from the scope of TSCA risk 
evaluations exposure pathways that are addressed or could in the future 
be addressed by other EPA-administered statutes and regulatory 
programs. See, e.g., Risk Evaluation for Methylene Chloride, section 
1.4.2 (Ref. 13). EPA asserted that such exclusions from TSCA risk 
evaluations were also permitted under the remaining text of TSCA 
section 9(b)(1), which establishes a process for determining whether to 
use EPA-administered authorities other than TSCA to protect against a 
risk ``[i]f the Administrator determines that a risk to health or the 
environment associated with a chemical substance or mixture could be 
eliminated or reduced to a sufficient extent by actions taken under the 
authorities contained in such other Federal laws.'' But upon 
reconsideration, neither provision in TSCA section 9(b)(1) is properly 
interpreted as authorizing exposure pathways to be excluded from TSCA 
risk evaluations.
    Intra-agency coordination is integral to ensuring that EPA actions 
are well-informed, effective, and efficient, but a general requirement 
under TSCA section 9(b)(1) to ``coordinate actions'' cannot be read to 
displace the more specific requirements under TSCA section 6(b)(4)(F) 
to conduct a risk evaluation that shall ``integrate and assess 
available information on hazards and exposures for the conditions of 
use of the chemical substance,'' and ``take into account . . . the 
likely duration, intensity, frequency, and number of exposures under 
the conditions of use of the chemical substance.'' And the remaining 
text of TSCA section 9(b) is directed at risk management action, which 
cannot logically take place until after EPA has conducted an evaluation 
and determined that a risk is presented. If exposure pathways covered 
by other laws are not assessed in TSCA risk evaluations, it is unclear 
how the Administrator would have sufficient information to determine 
under TSCA section 9(b) that a risk to health or the environment 
associated with a chemical substance could be eliminated or reduced to 
a sufficient extent under another Federal law, or whether it is in the 
public interest to protect against such risk by actions taken under 
TSCA--a finding that must, pursuant to TSCA section 9(b)(2), consider 
``all relevant aspects of the risk.'' Legislative history from TSCA's 
original 1976 enactment supports this understanding that TSCA section 
9(b)--the text of which was at that time split between TSCA section 
9(b) and TSCA section 6(c) (pertaining to risk management rulemaking 
procedures)--is properly interpreted in the context of risk management 
action rather than any preceding evaluation of risk (Ref. 18). As 
explained in the Conference Committee's 1976 report (Ref. 18) ``the 
requirement to examine other EPA laws and to make determinations 
applies only when the Administrator takes regulatory action to protect 
against an unreasonable risk under this Act.''
    EPA recognizes that there may be exposure-reducing impacts from 
existing regulations and intends to

[[Page 74300]]

consider reasonably available information when estimating exposures, 
including available monitoring data. There may also be circumstances 
where an unreasonable risk identified in the risk evaluation may be 
eliminated or reduced to a sufficient extent under the authorities 
contained in other Federal laws, such that a referral under TSCA 
section 9 might be appropriate. However, the mere existence of 
authority to assess or regulate a chemical, exposure pathway, or use 
under a statute other than TSCA does not equate to effective risk 
management of that chemical, exposure pathway or use, and an assumption 
that risk will--or could be--managed in the future cannot be used to 
satisfy the Agency's statutory obligations to evaluate existing 
chemical substances under TSCA and manage identified risks. Wholesale 
exclusion of identified exposure pathways for a chemical substance from 
the scope of the TSCA risk evaluation for that substance is 
inconsistent with EPA's obligations under TSCA section 6(b)(4)(F), as 
noted, as well as with requirements under TSCA section 26(h), (i) and 
(k) to make decisions based on science that are consistent with the 
best available science and are based on the weight of the scientific 
evidence, and to take into consideration reasonably available 
information relating to a chemical substance, ``including . . . 
exposure information,'' under the conditions of use. Furthermore, TSCA 
section 9 already contemplates a time and place for determination of 
whether EPA or another Federal agency can adequately address chemical 
risks under the authority of another Federal law: during the risk 
management rulemaking process after the risk has been identified in a 
risk evaluation.
    Accordingly, EPA is proposing changes in the rule to ensure that 
risk evaluations include all relevant exposure pathways, thereby 
providing the basis for development of strong, scientifically and 
legally defensible regulatory protections. Specifically, EPA is 
proposing to explicitly require that each risk evaluation assess all 
exposure routes and pathways relevant to the chemical substance under 
the conditions of use, including those that are regulated under other 
Federal statutes.
4. Comprehensive But Fit-For-Purpose
    While the changes described in Unit III.E.1. through 3. could all 
lead to future TSCA risk evaluations that are more comprehensive in 
scope, EPA recognizes the enormity of the challenge to complete these 
responsibilities within the timeframes set forth by Congress. The law 
provides the Agency with only 3 to 3.5 years to finalize a TSCA risk 
evaluation. The primary purpose of a TSCA risk evaluation is to support 
regulatory decision making--either to form the basis of a subsequent 
rulemaking to eliminate identified unreasonable risk under TSCA section 
6(a), or to determine that the chemical does not present unreasonable 
risk and therefore rulemaking is not necessary. Given the tens of 
thousands of existing chemicals, Congress further mandated that risk 
evaluations be completed on an ongoing basis and within specified 
timeframes.
    Risk evaluations under TSCA should not be so complex or 
procedurally cumbersome that they cannot reliably be completed within 
the timeframes required by the statute. At the same time, EPA cannot 
produce partial or incomplete TSCA risk evaluations or otherwise pursue 
risk evaluations in a manner that is incompatible with the statutory 
framework. Although EPA must balance resource expenditure and 
manageability, it must do so within the confines of its statutory 
mandate. As such, EPA is proposing some changes to the rule to ensure 
consistency with TSCA's text, structure, and purpose, while also 
clarifying where the statute provides flexibilities in how EPA conducts 
TSCA risk evaluations. For example, the proposed rule makes clear that 
a risk evaluation must assess the full range of conditions of use and 
all exposure routes and pathways, and that a single risk determination 
will be made on the chemical substance, but these can be accomplished 
with a fit-for-purpose approach that allows for varying types and 
levels of analysis.
    In order for TSCA implementation efforts to be sustainable, risk 
evaluations must be fit-for-purpose such that the Agency meets both the 
substantive statutory and regulatory requirements for conducting risk 
evaluations, while completing those evaluations within the statutory 
deadlines. (15 U.S.C. 2605(b)(4)). For example, while risk evaluations 
must consider the full spectrum of the chemical's conditions of use, 
not all of those conditions of use will warrant the same level of 
evaluation. As described in the 2017 final rule, EPA expects it may be 
able to complete its analysis on certain conditions of use and/or 
exposure pathways without extensive or quantitative evaluations of 
exposure. For example, lower-volume or less dispersive uses could 
receive less quantitative evaluations than uses with more extensive or 
complicated exposure patterns. In addition, not all identified 
toxicological endpoints may need the same level of analysis and 
consideration. Efficiencies may be gained in similarly tailoring 
approaches to peer review and/or systematic review. EPA can make 
scientifically sound risk determinations, considering reasonably 
available information, consistent with the best available science, and 
based on the weight of scientific evidence, through a combination of 
different types of information and risk assessment approaches. 
Ultimately, the proposed changes--TSCA risk evaluations that are both 
more comprehensive (e.g., that consider all exposure pathways) and 
better incorporate fit-for-purpose approaches that ensure EPA is 
meeting its statutory deadlines--will lead to more scientifically sound 
and legally defensible risk evaluations that support robust TSCA 
section 6(a) risk management rules that address any unreasonable risks 
of injury to human health or the environment.
5. Additional Efficiencies
    Based on the Agency's early implementation efforts and experience 
using the data gathering authorities afforded under the amended 
statute, it has become clear that EPA should identify, obtain, review, 
and synthesize data and information for risk evaluations much earlier 
in the TSCA existing chemical risk assessment and risk management 
process. Doing so will enable the Agency to finalize risk evaluations 
in the aggressive timeframes provided by the law, and as necessary, 
initiate risk management actions in a timely manner. EPA believes a 
more sustainable process would involve--either during prioritization or 
before--review of reasonably available information, identification of 
data needs and gaps, and preliminary efforts to scope the potential 
risk evaluation. Prioritization is the statutorily required initiating 
step in the TSCA existing chemical risk evaluation and risk management 
process. (15 U.S.C. 2605(b)). This 9- to 12-month process includes a 
risk-based screening to ultimately designate a chemical substance as a 
high-priority substance for risk evaluations or low-priority substance 
for which a risk evaluation is not warranted at the time. In the 
interest of creating additional efficiencies, EPA is proposing a 
process in which the Agency would publish and take comment during 
prioritization on preliminary information to inform the scope of the 
potential risk evaluation, which may result in the publication of the 
``draft scope'' before the initiation of the subsequent risk 
evaluation.
    More specifically, when early indications suggest the chemical is

[[Page 74301]]

likely to meet the criteria for a high-priority designation, EPA 
expects to publish the draft scope for public comment, to correspond 
with one of the two statutorily required 90-day comment periods 
associated with prioritization. Publishing this information early will 
allow the Agency to give an early indication as to the conditions of 
use, hazards, exposures and potentially exposed or susceptible 
subpopulations that the Agency expects to consider and may provide 
early indications as to how the Agency expects to conduct a fit-for-
purpose risk evaluation. This information will accompany the 
prioritization screening review criteria, and EPA will look to public 
comment and submission of available relevant data to inform both the 
final priority designation but also, if the chemical is then designated 
as a high priority, the information to inform the scope.
    As the first statutorily required step of the risk evaluation 
process, TSCA requires the Agency to publish the scope of the risk 
evaluation no later than 6 months after initiating the risk evaluation. 
(15 U.S.C. 2605(b)(4)(D)). This scope must include the hazards, 
exposures, conditions of use, and the potentially exposed or 
susceptible subpopulations the Administrator expects to consider. Under 
the 2017 final rule, however, EPA must publish the scope in a ``draft'' 
form, followed by no less than a 45-day public comment period. The 2017 
final rule states that the Agency generally expects to publish this 
draft no later than 3 months after initiation of the risk evaluation. 
Stakeholders supported this provision during the development of the 
2017 proposed rule; due to the gravity of the ``final'' scope on the 
risk evaluation process and possible state preemption, it was important 
for stakeholders to have the ability to comment on the draft scope. The 
proposed rule would maintain the requirement to publish a draft scope 
but set forth an expectation to publish the information as early as the 
prioritization process (e.g., concurrent with the proposed high-
priority designation), to allow the Agency more time to review and 
effectively use the public input in the development of the risk 
evaluation's scope. EPA requests comment on this proposed approach of 
publishing a draft scope during the prioritization process when it is 
clear that the chemical undergoing the prioritization process will be 
designated as a high-priority chemical.

F. Risk Determinations

1. Determinations on the ``Chemical Substance''
    EPA is proposing to clarify the regulations with respect to the way 
EPA makes a risk determination at the conclusion of the TSCA risk 
evaluation process. As described earlier, EPA believes, as supported by 
the plain language in the law, that the chemical's full spectrum of 
conditions of use must be included and assessed in the risk evaluation. 
EPA fully intends to continue to consider exposures associated with 
each condition of use. However, following that analysis, and for the 
reasons described in this Unit, the Agency no longer intends to make 
separate risk determinations for individual conditions of use. Instead, 
EPA is proposing changes to the regulations to clarify and codify the 
approach that the Agency originally proposed in the 2017 proposed rule 
(i.e., to make a single risk determination on the whole chemical 
substance). EPA believes that this approach is consistent with the 
statutory text and structure, as well as Congressional intent, and will 
enable the Agency's risk determinations to better reflect the potential 
for combined exposures across multiple conditions of use.
    In the 2017 proposed rule, EPA proposed that risk determinations be 
made on the ``chemical substance,'' consistent with the plain language 
of the law and Agency's interpretation of the new requirements in TSCA 
at that time. (Ref. 9 at pp. 7572, 7565 through 7566, and 7580). As 
described in the preamble, ``TSCA section 6(b)(4)(A) specifies that a 
risk evaluation must determine whether `a chemical substance' presents 
an unreasonable risk of injury to health or the environment `under the 
conditions of use.' The evaluation is on the chemical substance--not 
individual conditions of use--and it must be based on `the conditions 
of use.' ''. Thus, in the 2017 proposed regulatory text, EPA proposed 
to determine whether the chemical substance presents an unreasonable 
risk of injury to health or the environment under the conditions of 
use. (Ref. 9 at p. 7480).
    The 2017 proposed rule provided an exception that would allow EPA 
to make an ``early determination'' for a specific use that was deemed 
to present unreasonable risk. Where such an early determination was 
made, the risk management efforts to address that specific use could 
begin more expeditiously and not wait until the end of the 3 to 3.5 
year risk evaluation process (Ref. 8 at pp. 7568 and 7578). EPA did not 
propose a similar process for use-specific early determinations of no 
unreasonable risk. This exception made logical sense, in that, if a 
specific use of a chemical--in isolation--presented an unreasonable 
risk under TSCA, that chemical itself would necessarily present an 
unreasonable risk irrespective of risks posed by other uses. The 
converse may not be true. Where a specific use might not present an 
``unreasonable risk'' on its own, it may nonetheless contribute to an 
unreasonable risk determination when considered together with other 
uses of the chemical (e.g., when considering it in an aggregate 
exposure scenario).
    EPA received comment on the 2017 proposed rule that limiting 
``early determinations'' only to uses that present unreasonable risk 
was unfair, and encouraged the Agency to extend this concept of early, 
use-specific risk determinations to those uses determined not to 
present unreasonable risk. The 2017 final rule stated that ``EPA will 
determine whether the chemical substance presents an unreasonable risk 
of injury to health or the environment under each condition of uses 
[sic] within the scope of the risk evaluation, either in a single 
decision document or in multiple decision documents'' (Ref. 1). There 
was one particular passage in the preamble to the 2017 final rule which 
stated that EPA would make individual risk determinations for all 
conditions of use identified in the scope. (Ref. 1 at p. 33744).
    Concerns about a use-specific approach to risk determinations were 
raised as part of litigation on the final rule in Safer Chemicals v. 
EPA (Ref. 2 at p. 413), including that such an approach ignores the 
potential risks when the same individuals are exposed to the same 
chemical through multiple conditions of use (e.g., in the workplace and 
in the home). Those exposures, when combined, may present unreasonable 
risk, whereas, when viewed in isolation, may not. A panel of the Ninth 
Circuit Court of Appeals recognized the ambiguity of the regulation on 
this point, and ultimately held that a challenge regarding ``use-by-use 
risk evaluations [was] not justiciable because it is not clear, due to 
the ambiguous text of the Risk Evaluation Rule, whether the Agency will 
actually conduct risk evaluations in the manner Petitioners fear'' 
(Ref. 2 at p. 413). Subsequent to the Ninth Circuit's decision, EPA 
made individual risk determinations for each condition of use evaluated 
in the first ten risk evaluations (i.e., the condition of use-specific 
approach to risk determinations). That approach was

[[Page 74302]]

based on the particular passage in the preamble to the 2017 final rule 
stating that EPA would make individual risk determinations for all 
conditions of use identified in the scope. (Ref. 1 at p. 33744). The 
approach resulted in a mix of findings that certain conditions of use 
for a chemical ``present unreasonable risk'' while others ``do not 
present unreasonable risk.''
    As announced in June 2021 as the path forward for the first ten 
risk evaluations, EPA has revisited this decision and determined to 
revise the use-specific risk determinations for most of the first ten 
chemicals to reflect a single determination on the chemical substance 
itself (Ref. 7). These revisions did not require the Agency to change 
any of its underlying analyses in the risk evaluations. In the case of 
many of these first 10 chemicals, EPA had already determined that many 
or most of the individual conditions of use presented an unreasonable 
risk.
    In revising the risk determinations for the first 10 chemicals, EPA 
noted that in contrast to the portion of the preamble of the 2017 final 
rule that discusses the intent of the Agency to make multiple risk 
determinations, the regulatory text itself and other statements in the 
preamble reference a risk determination for the chemical substance 
under its conditions of use, rather than separate risk determinations 
for each of the conditions of use of a chemical substance. See for 
example, the revised risk determination for Methylene Chloride (Ref. 
13). Notwithstanding the one preambular statement about condition of 
use-specific risk determinations, the preamble to the 2017 final rule 
also contains support for a risk determination on the chemical 
substance as a whole.
    Although the Agency indicated in its June 2021 announcement that it 
would make a single risk determination on a chemical when it was 
``clear that majority of conditions of use warrant one determination,'' 
EPA now believes a better understanding of the statute is that a single 
determination on the chemical substance is required in every instance, 
and is proposing to make this clear in this procedural rule. TSCA 
section 6(b)(4)(A) specifies that in a risk evaluation, EPA must 
determine whether ``a chemical substance'' presents an unreasonable 
risk of injury to health or the environment ``under the conditions of 
use.'' This language clarifies that the risk determination is on the 
chemical substance--not individual conditions of use--and it must be 
based on ``the conditions of use.''
    Although EPA previously found ambiguity in TSCA section 6(b)(4)(A), 
it now believes that a better reading of the statute in light of its 
content and structure (and other reasons described in this paragraph) 
is that it requires EPA to simultaneously evaluate all conditions of 
use of a chemical substance. TSCA section 6(a) requires EPA to apply 
risk-management requirements ``to the extent necessary so that the 
chemical substance or mixture no longer presents such risk.'' This 
phrasing suggests that the chemical substance presents the unreasonable 
risk, and not specific conditions of use. Further, TSCA section 6(i)(1) 
explains that ``a determination by the Administrator under subsection 
(b)(4)(A) that a chemical substance does not present an unreasonable 
risk of injury to health or the environment shall be issued by order 
and considered to be a final agency action, effective beginning on the 
date of issuance of the order.'' Similarly, TSCA section 6(i)(2) 
explains that ``a final rule promulgated under subsection (a), 
including the associated determination by the Administrator under 
subsection (b)(4)(A) that a chemical substance presents an unreasonable 
risk of injury to health or the environment, shall be . . . a final 
agency action, effective beginning on the date of promulgation of the 
final rule.'' Both of these provisions speak in terms of whether the 
chemical substance presents unreasonable risk. Neither provision 
mentions the conditions of use. The structure of TSCA section 6(i) also 
implies a binary decision by not addressing a scenario in which a 
chemical substance would be subject to TSCA section 6(i)(1) and (2).
    EPA's view that there should be one determination on the chemical 
substance is further bolstered by TSCA's preemption provisions at 
Section 18, and its numerous references to ``chemical substance.'' In 
TSCA section 18(a)(1)(B)--titled ``Chemical substances found not to 
present an unreasonable risk or restricted''--the law states that 
preemption applies, for example, when EPA issues ``the determination'' 
in TSCA section 6(i)(1) (i.e., a determination that the chemical 
substance does not present an unreasonable risk). EPA notes in 
particular that the word ``determination'' in this provision is 
singular, suggesting Congress did not envision multiple determinations 
under TSCA section 6(i)(1). Additionally, TSCA section 18(a)(1)(B)(ii) 
states that permanent preemption is triggered by a final TSCA section 
6(a) risk management rule for ``the chemical substance,'' suggesting 
again that Congress did not envision that TSCA section 6(a) risk 
management rules would address only risks presented by individual uses 
or some subset of a chemical's uses, but rather unreasonable risk 
presented by the chemical as a whole.
    Based on its text and structure, EPA now reads TSCA as requiring 
the Agency, in each risk evaluation, to make a single risk 
determination of the chemical substance. EPA does not believe that the 
statutory text and structure permit the Agency to make separate risk 
determinations for each condition of use. The legislative history also 
tends to favor this reading, including Congressional floor statements 
made on the day of passage supporting the risk determination being for 
the chemical substance. ``. . . EPA's understanding of a chemical's 
conditions of use . . . will be critical to EPA's final determination 
of whether a chemical is safe or presents an unreasonable risk that 
must be controlled'' and S3520 ``A Section 6(i) order, determining that 
a chemical substance does not present an unreasonable risk under 
conditions of use, is similarly final Agency action applicable to all 
those conditions of use that were identified in the scope of EPA's risk 
evaluation on the chemical substance'').'' (Ref. 11).
    Although the Agency has previously referred to this as a ``whole 
chemical'' approach, this descriptor may have created some confusion 
regarding the Agency's intent and purpose. EPA believes that a more 
accurate description of the approach is simply one where the Agency 
makes its risk determination for the chemical substance. A 
determination that a chemical substance presents an unreasonable risk 
does not mean that the entirety or whole of that chemical's uses--or 
even a majority of uses--presents an unreasonable risk. Rather, EPA may 
determine that a chemical substance presents an unreasonable risk based 
on risk associated with even a single condition of use.
    Some have criticized this approach in public comments on the 
revised risk determinations. They have noted, for example, that a 
singular risk determination could create confusion as to whether all 
uses or only certain uses of a chemical pose unreasonable risk. 
Fundamentally, EPA believes these concerns are risk communication 
issues that the Agency can and intends to continue to improve on. EPA 
will in every risk evaluation provide a rationale and explanation as to 
which conditions

[[Page 74303]]

of use or exposure pathways are significant contributors to risk. The 
Agency is committed to clearly communicating on the Agency's analysis 
of particular uses within the risk evaluation and will not make 
statements about the risk associated with the chemical substance absent 
such explanation. Rather, as indicated in the proposed regulatory text 
at 40 CFR 702.37(a)(5), and in order to inform risk management 
requirements, EPA generally expects every risk determination to 
identify which conditions of use are--or are not--significant 
contributors to EPA's determination that the risk presented is 
unreasonable. That said, for those chemical substances that EPA 
determines present unreasonable risk, the risk evaluation is not the 
end of the TSCA process. The primary purpose of a risk evaluation is 
not to provide the public with guidance or suggested actions with 
respect to particular chemical uses. Risk evaluations are scientific 
documents intended to inform EPA decisions as to whether regulatory 
action is needed to address unreasonable risks to human health or the 
environment. Ultimately, when the TSCA existing chemicals review 
process--including any TSCA section 6(a) rulemaking to manage risk--is 
complete, the public should have full confidence that the chemical can 
only be manufactured, processed, distributed in commerce, used and 
disposed of in accordance with the associated risk management 
requirements, and that the chemical substance no longer presents an 
unreasonable risk.
    Likewise, others have expressed concern that EPA will use a 
singular risk determination to regulate in an overly broad manner. A 
determination of unreasonable risk for a chemical substance does not 
mean that EPA will, by default, propose or finalize a section 6(a) risk 
management rule requiring all manufacture or use of the chemical 
substance to be banned. EPA's statutory authority to regulate chemicals 
under TSCA section 6 is available only ``to the extent necessary so 
that the chemical substance or mixture no longer presents 
[unreasonable] risk.'' (15 U.S.C. 2605(a)). EPA has a range of 
authorities available under TSCA section 6(a) to address unreasonable 
risk, including--but not limited to--requiring additional occupational 
safety measures, product labels, or concentration limits. Where such 
measures can eliminate unreasonable risk, EPA may propose them as part 
of the risk management rulemaking process. EPA's determination of 
appropriate regulatory requirements will be on a case-by-case basis, 
and will not regulate chemical substances in a manner that is 
inconsistent with the requirements of TSCA sections 6(a) and (c)(2). 
For example, EPA may derive an exposure limit in the risk evaluation. 
Such a limit would necessarily be based solely on risk-related 
information, adhering to the statutory directive not to consider costs 
or other non-risk factors during the risk evaluation. However, because 
EPA is required to consider costs and other non-risk factors during the 
risk management phase, including whether uses of a substance are 
critical to Federal mission needs, or whether alternatives for a use of 
a substance exist, the exposure limit presented in a risk evaluation 
may not always or automatically signal the manner in which EPA will 
regulate occupational risks during the risk management phase.
    It is important to note, however, in exercising EPA's authority 
under TSCA section 6(a) to ensure that ``the chemical substance . . . 
no longer presents such risk,'' EPA may regulate conditions of use that 
do not themselves contribute to unreasonable risk for a given chemical. 
For example, where a risk evaluation's underlying analysis suggests 
that particular use downstream in the supply chain is significantly 
contributing to unreasonable risk determination for the chemical 
substance, EPA's risk management actions need not apply only to the 
downstream use. EPA may, for example, determine that elimination of the 
unreasonable risk requires regulation of the chemical's upstream 
manufacture, processing or distribution in commerce--even where the 
upstream activity itself does not directly result in the exposures that 
present the unreasonable risk.
    EPA considered whether to re-propose a process for making use-
specific early determinations of unreasonable risk prior to completing 
the risk evaluation for the remaining conditions of use, as 
contemplated in the original 2017 proposed rule. However, based on 
experience in conducting risk evaluations on the first 10 chemicals and 
implementing the new requirements in TSCA section 6, the notion of 
early, use-specific risk determinations is not practical or realistic 
within the statutory deadlines. The theoretical benefit of such an 
approach--enabling the early start of risk management efforts for the 
subset of uses that are clearly of highest risk--is outweighed by the 
burdens of managing the completion of multiple risk evaluation 
processes on a single chemical followed by potentially multiple 
rulemakings, each of which must comply with statutory deadlines. In the 
event that there is a known, imminent and unreasonable risk of serious 
or widespread injury to health or the environment (i.e., imminent 
hazard) associated with a use or chemical that the Agency needs to 
address immediately, TSCA section 7 provides EPA the authority to take 
such immediate action.
    EPA believes the approach, consistent with the 2017 proposed rule, 
(i.e., to make a single risk determination on the chemical substance) 
is aligned with the statutory text and structure, and will ensure that 
the Agency is best positioned to incorporate reasonably available 
information, make determinations consistent with the best available 
science and based on the weight of scientific evidence, including, 
where appropriate, risk determinations that consider aggregate exposure 
resulting from multiple conditions of use. (15 U.S.C. 2625(h), (i), and 
(k)). As such, EPA is proposing that risk evaluations will always 
culminate in a single risk determination on the ``chemical substance'' 
instead of individual risk determinations on individual conditions of 
use. EPA is proposing related conforming changes throughout the 
regulatory text, including the proposed addition of 702.37(a)(5) and 
the explicit mention of a single determination in 702.39(f)(1).
2. ``Unreasonable Risk'' Considerations
    TSCA requires that a risk evaluation include a determination of 
whether or not a chemical presents unreasonable risk, and further 
requires that this determination be independent of cost or other non-
risk factors. (15 U.S.C. 2506(b)(4)(A) and (F)(iii)). Neither TSCA nor 
the 2017 final rule define ``unreasonable risk'' given the inherently 
unique nature of each risk evaluation and the need for EPA to make this 
determination on a case-by-case basis. As described in the preamble to 
the 2017 final rule (Ref. 1 at p. 33735), 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 subpopulations), the severity of 
hazard (the nature of the hazard, the irreversibility of hazard), and 
uncertainties.

[[Page 74304]]

    The 2016 amendments also required that EPA's determination of 
unreasonable risk consider the risks to potentially exposed or 
susceptible subpopulations. Where EPA identifies risks as part of the 
risk evaluation, the risks to a potentially exposed or susceptible 
population may be more significant or severe than the risks to the 
general population. EPA would more explicitly reflect this statutory 
requirement in proposed Sec.  702.39(f), as the 2017 final rule did not 
explicitly reference the statutory requirement to consider the risk to 
potentially exposed or susceptible subpopulations when making the final 
risk determination. Additionally, as discussed more fully in Unit 
III.G.4., the proposed rule clarifies that ``overburdened communities'' 
are one example of a group that may be considered as potentially 
exposed or susceptible subpopulations within a given risk evaluation. 
``Overburdened communities'' may include various populations or 
communities in the United States that potentially experience 
disproportionate environmental harms and risks or multiple burdens from 
chemical exposure. The proposed change clarifies that EPA will consider 
the risk to potentially exposed or susceptible subpopulations as part 
of its determination of whether or not the chemical presents 
unreasonable risk.
    Likewise, and as discussed further in Units III.G.2. and 3., EPA's 
determination of unreasonable risk from the chemical substance will 
also consider, where relevant, the Agency's analyses on aggregate 
exposures and cumulative risk. For example, where a single population 
is exposed to a chemical through multiple routes or pathways, EPA's 
assessment of those aggregate exposures may inform the determination of 
whether that chemical presents an unreasonable risk. Similarly, a 
cumulative risk assessment may be conducted on a category of chemicals, 
where the science supports this type of assessment, and the findings 
may inform the unreasonable risk determination for the category.

G. Risk Evaluation Considerations

1. Occupational Exposure Assumptions
    EPA is proposing some clarifications to the assumptions that it 
will and will not apply in risk evaluations related to worker exposure.
    In carrying out the first ten TSCA chemical risk evaluations, as 
part of the unreasonable risk determinations, EPA assumed that workers 
were provided and always used personal protective equipment (PPE) in a 
manner that achieves the stated assigned protection factor (APF) for 
respiratory protection, or used impervious gloves for dermal 
protection. In support of this assumption, EPA relied on public 
comments indicating that some employers, particularly in the industrial 
setting, provide PPE to their employees and follow established worker 
protection standards (e.g., OSHA requirements for protection of 
workers). As EPA noted in prior risk evaluations (e.g., Risk Evaluation 
for Methylene Chloride (Dichloromethane, DCM), 126 (Ref. 13 at p. 126), 
the consideration of assumed use of PPE in a risk determination could 
lead to an underestimation of the risk to workers. Further, parties in 
litigation as well as public commenters on several TSCA risk 
evaluations argued that making risk determinations based on assumptions 
of PPE conflates the risk evaluation and risk management phases. In 
June 2021, the Agency announced it would be revisiting the risk 
determinations that were based on these assumptions and noted its plans 
to consider information on use of PPE and other ways industry protects 
its workers during the risk management process (Ref. 7).
    TSCA requires that EPA evaluate the chemical substance under the 
intended, known, or reasonably foreseen circumstances associated with 
the chemical's manufacture, processing, distribution in commerce, use 
and disposal. EPA believes that the blanket occupational exposure 
assumptions on PPE do not reflect the known or reasonably foreseen 
chemical exposures that impact workers, and their continued application 
in TSCA risk evaluations would result in underestimates of risk. For 
example, workers may be highly exposed because they are not covered by 
Occupational Safety and Health Administration (OSHA) standards, their 
employers are out of compliance with OSHA standards, or because the PPE 
is not sufficient to address the risk or their PPE does not fit or 
function properly. Further, many of OSHA's chemical-specific 
permissible exposure limits were largely adopted in the 1970s and have 
not been updated since they were established (Ref. 19). Additionally, 
TSCA risk evaluations are subject to statutory science standards, an 
explicit requirement to consider risks to potentially exposed or 
susceptible subpopulations, and a prohibition on considering costs and 
other non-risk factors when determining whether a chemical presents an 
unreasonable risk that warrants regulatory actions--all requirements 
that do not apply to development of OSHA regulations. As such, EPA may 
find unreasonable risk for purposes of TSCA notwithstanding OSHA 
requirements. Where risk evaluations assume fully protective PPE use, 
and therefore little or no exposures for workers, the risk evaluations 
may underestimate and/or fail to identify unreasonable risk. EPA is 
requesting public comment on how the Agency can provide a transparent 
and detailed basis for the proposed unreasonable risk determination and 
existing chemical exposure limits derived from the risk evaluation 
process.
    EPA is not suggesting that there is widespread non-compliance with 
applicable OSHA standards. In fact, EPA has received public comments 
from industry in response to various EPA documents associated with TSCA 
risk evaluations about occupational safety practices currently in use 
at their facilities, including adherence to OSHA standards and non-OSHA 
industry guidelines. EPA also acknowledges that other Federal agencies 
and their contractors that use chemicals may similarly have well-
established occupational control measures in place. EPA will consider 
comments received during the risk evaluation process, as well as other 
information on use of PPE and other ways industry and Federal agencies 
protect their workers, as potential ways to address unreasonable risk 
during the risk management process. EPA recognizes that in some 
instances and in certain workplace locations, particularly advanced 
manufacturing facilities (e.g., those involved in the aerospace and 
defense industrial base industrial sectors) there could be well-
established occupational safety protections in place. As EPA moves 
forward with risk management rules, the Agency will strive for 
consistency with existing OSHA requirements and/or best industry 
practices when those measures would address the identified unreasonable 
risk and would adopt a similar approach when making decisions about 
managing risks for uses of chemicals that are required to meet national 
security and critical infrastructure mission imperatives for other 
Federal agencies. EPA will proactively communicate with Federal 
agencies to identify such circumstances with an aim to propose measures 
in the risk management process to address occupational risk that will 
meet TSCA's statutory requirement to eliminate unreasonable risk of 
injury to health and the environment, while also leveraging ongoing 
interagency dialogue and striving to avoid potential

[[Page 74305]]

impacts to mission and infrastructure critical uses.
    EPA is proposing regulatory amendments to clarify that, in future 
risk evaluations, EPA's consideration of occupational exposure 
scenarios in the exposure assessments will take into account reasonably 
available information, including information regarding known and 
reasonably foreseen circumstances where subpopulations of workers are 
exposed due to absence or ineffective use of personal protective 
equipment. The EPA intends to assess and include in the risk evaluation 
the use of PPE, any engineering controls, and other industrial hygiene 
practices at industrial, commercial, and Federal facilities. Where 
information is made available, the Agency will take into account known 
occupational control measures in the exposure assessments. However, the 
Agency will not consider, as part of the unreasonable risk 
determination, exposure reduction based on assumed use of PPE by 
workers. For purposes of the risk determination at Sec.  702.39(f)(2), 
EPA would distinguish between an ``assumed'' use of PPE and a use that 
is supported by the reasonably available information and therefore 
known to be inherent in the performance of an activity. For example, 
where EPA has reasonably available information that substantiates use 
and effectiveness of PPE (e.g., information demonstrating that 
performance of a condition of use is impossible in the absence of PPE), 
EPA generally expects to take that information into account in the risk 
determination. The exposure reduction information (e.g., use of PPE) 
from the risk evaluation's exposure assessment would then be considered 
and incorporated in a future risk management action, as appropriate and 
as required pursuant to TSCA section 6(a), and we encourage commenters 
with interests or concerns on this to offer comments on this point in 
connection with such a future action.
2. Aggregate Exposure
    Pursuant to TSCA section 6(b)(4)(F)(ii), when conducting a risk 
evaluation, EPA must ``describe whether aggregate or sentinel exposures 
to a chemical substance under the conditions of use were considered, 
and the basis for that consideration.'' While there is no mandate to 
conduct aggregate exposure analyses, EPA may conduct aggregate exposure 
analyses at its discretion. In the 2017 final rule EPA defined 
aggregate exposure as ``the combined exposures to an individual from a 
single chemical substance across multiple routes and across multiple 
pathways.'' In this proposed rule, EPA is proposing slight revisions to 
the definition. Aggregate exposure analysis is not only used to assess 
exposure to an individual, but may also be used to assess exposure for 
a population, subpopulation or the environment. Thus, EPA is proposing 
to strike ``to an individual'' from the definition, which is consistent 
with the definition used in General Principles for Performing Aggregate 
Exposure and Risk Assessments (Ref. 20). Additionally, EPA is proposing 
to strike ``single'' chemical, as TSCA allows the Agency to conduct 
risk evaluations on categories of chemicals.
    The consideration of an aggregate exposure assessment may be 
particularly important for assessing chemical risks to overburdened 
communities. If a community is exposed to a chemical substance through 
multiple routes and/or pathways (e.g., exposure via air, land, and 
water or exposure via drinking water and water recreation) and/or from 
multiple sources (e.g., through different conditions of use occurring 
at multiple facilities), the Agency has the authority to aggregate 
those exposures, subject to the best available science standard, per 
TSCA section 26(h). Not only does the Agency have the authority, but in 
developing a comprehensive risk estimate for a chemical substance, it 
is the Agency's responsibility to consider the aggregation of what may 
be lower individual exposures from individual conditions of use and 
routes of exposure. EPA is committed to conducting an aggregate 
assessment, as supported by the science, in future TSCA risk 
evaluations. In an aggregate exposure assessment, it may be appropriate 
to also consider potential background exposures from non-TSCA uses that 
are not within the scope of the risk evaluation. EPA could also 
consider the disproportionate impacts that background exposures may 
have on overburdened communities to inform the final unreasonable risk 
determination.
3. Cumulative Risk
    Advancing the science to support cumulative risk assessment is a 
high priority for the Agency. Cumulative risk assessment is applicable 
to all lifestages, and could inform the Agency's efforts to understand 
and mitigate those risks to potentially exposed or susceptible 
subpopulations, including children and overburdened communities. 
Several reports from the National Research Council (NRC)--including the 
1994 report Science and Judgment in Risk Assessment (Ref. 21) the 2008 
report Phthalates and Cumulative Risk Assessment: The Tasks Ahead (Ref. 
22), and the 2009 report Science and Decisions: Advancing Risk 
Assessment (Ref. 23)--have highlighted the importance of understanding 
the combined risk from multiple chemical stressors. These reports, as 
well as statutory requirements such as those presented in the Food 
Quality Protection Act of 1996 (Ref. 24), have helped drive EPA's 
evolving work on cumulative risk assessment. Because individuals are 
co-exposed to many chemicals in their daily lives, some of which may 
have the same health effects, EPA believes that in some cases the best 
approach to assess risk to human health may be to look at the combined 
risk to health from multiple chemicals.
    Although TSCA does not mandate that EPA must conduct cumulative 
risk assessments, TSCA does require that EPA, when conducting TSCA risk 
evaluations in 3 to 3.5 years (15 U.S.C. 2605(b)(4)(G)), consider the 
reasonably available information, consistent with the best available 
science, and make decisions based on the weight of the scientific 
evidence (15 U.S.C. 2625(h), (i), and (k)). EPA recognizes that for 
some chemical substances undergoing risk evaluation, the best available 
science may indicate that the development of a cumulative risk 
assessment is appropriate to ensure that risk to human health and the 
environment is adequately characterized. TSCA also gives the Agency the 
authority to consider the combined risk from multiple chemical 
substances or a category of chemical substances. (15 U.S.C. 2625(c)). 
Under TSCA section 26(c), EPA may take ``any action authorized'' under 
any provision of TSCA, in accordance with that provision with respect 
to a category of chemical substances or mixtures of chemical 
substances. TSCA defines ``category of chemical substances'' as a group 
of chemical substances the members of which are 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, or the 
members of which are in some other way suitable for the classification 
as such for purposes of [TSCA].'' (15 U.S.C. 2625(c)). This definition 
provides EPA with the flexibility to group chemical substances for 
inclusion in a risk evaluation and a cumulative risk assessment when 
supported by the best available science.
    There are multiple definitions of the term ``cumulative risk 
assessment.'' For TSCA risk evaluations, the Agency is

[[Page 74306]]

currently relying on the definition in EPA's Framework for Cumulative 
Risk Assessment that defines cumulative risk assessment as ``an 
analysis, characterization, and possible quantification of the combined 
risks to health and/or the environment from multiple agents and/or 
stressors'' (Ref. 25). This could include evaluation of multiple 
chemical substances that jointly exert a common toxic effect. Exposures 
to these chemicals could occur through multiple exposure pathways and 
through multiple routes of exposure. EPA expects to use available EPA 
(Refs. 26, 27, 28, 29), OECD (Ref. 30), and World Health Organization/
International Programme on Chemical Safety (WHO/IPCS) (Ref. 31) 
guidances that outline two principal considerations for grouping 
chemicals for inclusion in a cumulative risk assessment: (1) 
Toxicologic similarity; and (2) Evidence of co-exposure over a relevant 
timeframe.
    A risk evaluation on a single chemical may not accurately provide a 
complete understanding of the risks to an exposed population, given 
simultaneous exposure to multiple chemicals. In turn, without 
considering the cumulative risk of chemicals, the Agency's risk 
mitigation may not fully be able to consider the public-health 
implications of various risk management options for reducing exposure. 
EPA is committed to considering applying cumulative risk assessment 
approaches, as appropriate and where such analysis, based on reasonably 
available information, represents the best available science, for 
future chemicals undergoing risk evaluation. The Agency developed and 
released a Draft Proposed Principles of Cumulative Risk Assessment 
Under the Toxic Substances Control Act (Ref. 32) and Draft Proposed 
Approach for Cumulative Risk Assessment of High-Priority Phthalates and 
a Manufacturer Requested Phthalate Under the Toxic Substances Control 
Act (Ref. 33) for public comment and peer review in February 2023. The 
Agency is considering feedback from both stakeholders and peer 
reviewers and EPA will continue to develop robust methodology for the 
inclusion of cumulative risk assessment in TSCA risk evaluations. EPA 
seeks comment on how the Agency could incorporate provisions for 
cumulative risk assessment into our risk evaluation procedures in a way 
that would accommodate future advancements in the science of cumulative 
risk assessment as well as ensure that the scope and complexity of any 
such assessments is consistent with that envisioned by Congress when it 
established deadlines for conducting risk evaluations.
    As described in Unit III.G.4., TSCA also explicitly requires EPA's 
risk evaluations to consider unreasonable risk to ``potentially exposed 
or susceptible subpopulations,'' and the statute provides authority to 
consider non-chemical as well as chemical stressors when identifying 
these subpopulations. Non-chemical stressors are factors found in the 
built, natural, and social environments including physical factors 
(e.g., geographic location) and psychosocial factors (e.g., poor 
nutrition) (Ref. 34). EPA's Office of Research and Development has 
defined cumulative impacts as the totality of exposures to combinations 
of chemical and non-chemical stressors and their effects on health, 
well-being, and quality of life outcomes (Ref. 34) and may or may not 
include toxicologically defined risk. EPA has not to date considered 
cumulative impacts in TSCA risk evaluations, but may in the future as 
appropriate data, methods, and guidance are available.
4. 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 the term as ``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)). TSCA 
does not further define ``greater susceptibility'' or ``greater 
exposure,'' giving the Agency discretion to interpret these terms. 
Greater susceptibility could include increased risk of experiencing an 
adverse effect due to one's lifestage or a pre-existing condition or 
circumstance (e.g., immune-compromised conditions, lifestyle factors 
such as smoking status or alcohol abuse, age, ethnicity, or sex). This 
is consistent with EPA's Policy on Children's Health to protect 
children from environmental exposures by consistently and explicitly 
considering early life exposures and lifelong health in all human 
health decisions. The Agency will use its discretion and interpret 
``greater exposure'' to potentially include fenceline communities 
(e.g., those communities in close proximity to facilities emitting air 
pollutants or living near effluent releases to water) or body burden. 
Additionally, Congress' inclusion of ``such as'' allows EPA to 
potentially identify communities who ``may be at greater risk than the 
general population.'' Thus, EPA may evaluate any subpopulation that may 
be at greater risk due to greater susceptibility or exposure, and 
identify additional subpopulations other than those examples listed in 
the statute, where warranted.
    To ensure that the TSCA risk evaluations conducted for existing 
chemicals fully consider and evaluate the risks to these vulnerable 
communities, EPA is proposing to amend the regulatory definition of 
``potentially exposed or susceptible subpopulations.'' Specifically, 
EPA is proposing to add ``overburdened communities''--communities that 
may be disproportionately exposed or impacted by environmental harms--
to the list of example subpopulations. The disproportionality can be as 
a result of greater vulnerability to environmental hazards, lack of 
opportunity for public participation, or other factors. Increased 
vulnerability may be attributable to an accumulation of negative or 
lack of positive environmental, health, economic, or social conditions 
within these populations or places. The term describes situations where 
multiple factors, including both environmental and socio-economic 
stressors, may act cumulatively to impact health and the environment 
and contribute to persistent environmental health disparities. These 
situations may apply to communities with environmental justice 
concerns.
    EPA's 2017 proposed rule proposed a definition of PESS that 
included more examples of PESS than set forth by Congress in the 
statutory definition. EPA did not finalize that definition as proposed. 
In response to public comments, the Agency explained 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'' and that 
EPA did not want to imply exclusion of other subpopulations. However, 
EPA now believes that it is appropriate to propose the addition of 
``overburdened communities'' to the definition of PESS because it 
reflects the Agency's understanding and acknowledgment that exposure to 
a chemical substance may disproportionately impact communities already 
experiencing disproportionate and adverse human health or environmental 
burdens. Nothing in TSCA or this proposed rule

[[Page 74307]]

would prevent the Agency from identifying another group or 
subpopulation as a ``potentially exposed or susceptible subpopulation'' 
in a given TSCA risk evaluation and specifically considering those 
exposures and risks within.
    To identify overburdened communities when conducting a risk 
evaluation, EPA will engage the public throughout the TSCA 
prioritization and risk evaluation processes, work with EPA offices 
such as the Office of Environmental Justice and External Civil Rights 
and the Office of Research and Development, and may use available 
screening tools, such as EJSCREEN (Ref. 35) or EnviroAtlas (Ref. 36). 
These and other tools may also allow the Agency to capture greater 
susceptibility or greater exposure using the data layers for 
socioeconomic factors (e.g., income/poverty, education) or location 
(e.g., housing, employment, geography), and for environmental 
indicators (e.g., air toxics cancer risk, respiratory hazard index, 
particulate matter levels, ozone, Superfund site proximity, hazardous 
waste proximity, proximity to multiple chemical manufacturing or 
processing facilities), which may provide information for future 
cumulative assessment. EPA also continues to develop approaches for 
assessing the risk to overburdened communities. For example, in 2022 
EPA submitted for peer review the Screening Level Approach for 
Assessing Ambient Air and Water Exposures to Fenceline Communities (Ref 
16). This proposed screening level methodology evaluated the potential 
chemical exposures and associated potential risks to fenceline 
communities, or communities in close proximity, and thus commonly at 
greater exposure, to chemical emission sources. The Agency continues to 
develop risk evaluation approaches to help determine risk from all 
relevant exposure pathways with an emphasis on exposures to these 
commonly overburdened communities.

H. Science Policy and Scientific Standards

1. Scientific Guidelines and Procedures
    Congress recognized the importance of Agency policies, procedures 
and guidance necessary to facilitate implementation of the 2016 
amendments to TSCA. (15 U.S.C. 2625(l)(1)). This proposed rule, as does 
the 2017 final rule, codifies the use of appropriate Agency guidance in 
the development of risk evaluations (proposed Sec.  702.37(a)(1)). 
Agency guidance and methodology documents, which may include publicly 
available handbooks, frameworks, protocols, or any other process 
support documents have long provided process and method transparency to 
Agency scientific work products. The appropriateness of the documents 
relates to their application in the methods, approaches, and science 
policy decisions used in TSCA risk evaluations. For example, the 
Exposure Factors Handbook: 2011 Edition (Ref. 10), provides exposure 
assessors inside the Agency as well as outside, with data on standard 
factors to calculate human exposure to environmental agents. Other EPA 
guidance and methodology documents provide background for the 
development of the TSCA risk evaluations, specifically the EPA 
Guidelines for Carcinogen Risk Assessment (Ref. 37), and the EPA 
Supplemental Guidance for Assessing Susceptibility from Early-Life 
Exposure to Carcinogens (Ref. 38). EPA will continue to use these and 
other existing Agency guidances in the development of TSCA risk 
evaluations. EPA may develop and use additional guidance as needed 
using a transparent process.
2. Peer Review
    Science is the foundation that supports the work of EPA, and this 
is equally true for TSCA risk evaluations. The quality and integrity of 
the science are vital to the credibility of the Agency's decisions and 
processes, including but not limited to the evaluation of risks from 
chemicals, determination of whether a chemical presents an unreasonable 
risk, decisions on how best to manage that risk, and ultimately the 
Agency's effectiveness in pursuing its mission to protect human health 
and the environment. One important element in ensuring that decisions 
are consistent with the best available science and based on the weight 
of scientific evidence is to have an open, transparent and independent 
scientific peer review process along with opportunities for public 
comment.
    EPA has a long-standing history of peer review and has shown its 
commitment to peer review in the TSCA program. TSCA section 26(o) 
required EPA to establish an advisory committee, known as the Science 
Advisory Committee on Chemicals (SACC), to provide independent advice 
and expert consultation with respect to the scientific and technical 
aspects of issues relating to the implementation of TSCA. EPA expects 
to continue to obtain scientific advice and peer review from the SACC. 
The 2017 final rule explicitly required peer review to be conducted on 
all risk evaluations, which the Agency did for each of the first ten 
risk evaluations (Ref. 8). Reports from those peer review committees 
proved extremely instructive and resulted in more robust and 
scientifically defensible products and improvements to EPA methods used 
in the risk evaluation process.
    The Agency remains committed to using peer review in the 
development of TSCA risk evaluations and any associated methods or 
approach type documents and proposes to retain the provision to require 
peer review in the risk evaluation process. However, EPA is proposing 
some modifications to the language from the 2017 final rule to provide 
increased clarity on both the guidance the Agency will use to conduct 
peer review and on what peer review will be conducted. First, the 
Agency proposes removing the reference to specific versions of guidance 
documents. The 2017 final rule names specifically the EPA Peer Review 
Handbook 4th Edition 2015 (Ref. 39) and OMB's Information Quality 
Bulletin for Peer Review (Ref. 40). While at the time of this proposed 
rule these documents were and still are applicable, the Agency 
recognizes that these documents may be updated and/or their names 
modified and seeks to avoid confusion as to which guidance documents 
will be used. The Agency proposes at Sec.  702.41 to refer instead to 
``applicable peer review policies, procedures, guidance documents, and 
methods adopted by EPA and the Office of Management and Budget (OMB) to 
serve as the guidance for peer review activities. EPA interprets 
``applicable'' to reference the most current versions and believes this 
change will appropriately incorporate any future versions of peer 
review guidance documents from both the Agency and OMB (i.e., the EPA 
Peer Review Handbook and OMB Final Information Quality Bulletin for 
Peer Review).
    The peer review guidance documents discussed in this Unit III.H.2., 
as well as their predecessors, provide guidance on all aspects of the 
peer review process. This includes guidance on when to conduct peer 
review and on what should be considered in selecting the appropriate 
peer review approach, including allowable latitude for the type of peer 
review that EPA can conduct. 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 has previously used 
this flexibility in the TSCA program and sought a letter peer review, 
as opposed to, for instance, a committee established under the Federal 
Advisory Committee Act (FACA) (5 U.S.C. 10), to peer review new and 
updated information used in

[[Page 74308]]

the revised draft risk evaluation for Pigment Violet 29 (Ref. 41).
    The Agency fully intends to uphold the EPA Peer Review Policy 
Statement, which states in part, ``. . . For highly influential 
scientific assessments, external peer review is the expected procedure. 
For influential scientific information intended to support important 
decisions, or for work products that have special importance in their 
own right, external peer review is the approach of choice . . .'' 
However, as discussed in the EPA Peer Review Handbook 4th Edition, 
there are circumstances when the additional peer review of influential 
products that have had adequate prior peer review may not be necessary 
(Ref. 39). As the Agency looks to the future of TSCA risk evaluations, 
it is expected that specific approaches may be used repeatedly, after 
due consideration of complexity, novelty, and prior peer review. That 
is, there may be situations when repeated peer review is not warranted.
    For example, EPA did not peer review the 2020 1,4-Dioxane; 
Supplemental Analysis to the Draft TSCA Risk Evaluation (Ref. 42). In 
response to peer review of the draft risk evaluation for 1,4-dioxane, 
published in September 2019 (Ref. 43), members of the SACC, as well as 
public commenters, highlighted omissions in the draft evaluation, 
specifically 1,4-dioxane exposures as a byproduct in products and 
general population exposure from the surface water pathway. As a 
result, those conditions of use from the presence of 1,4-dioxane as a 
byproduct in consumer use were included in the scope of a supplemental 
analysis to the draft risk evaluation. In that situation, because the 
analytical approaches to assessing the unreasonable risk associated 
with these conditions of use mirrored those approaches used for the 
conditions of use evaluated in the peer reviewed September 2019 draft 
risk evaluation and there was not new or novel scientific information 
to consider, the Agency determined that additional peer review was not 
warranted, but sought public comment on the supplemental analysis.
    EPA believes that future risk evaluations and associated analyses 
may present similar circumstances for EPA's consideration. Rather than 
peer reviewing an entire risk evaluation, in adhering to applicable 
guidance, it may be appropriate for EPA to conduct peer review on only 
portions or sections that constitute unreviewed influential 
information. EPA also expects that a TSCA risk evaluation may use peer 
reviewed products (e.g., risk assessments, hazard assessments, models), 
or portions thereof, conducted by another EPA office or other 
authoritative body (e.g., state, national, or international programs), 
for which both the best available science and weight of scientific 
evidence standards were adhered to (see Unit III.I.1.). EPA's Peer 
Review Handbook specifically references circumstances that may not 
necessitate additional peer review including ``work that has been 
previously reviewed in a manner consistent with the OMB Peer Review 
[Bulletin] and EPA's Peer Review Handbook'' (Ref. 39). Thus, this 
portion or section of a TSCA assessment may not need additional peer 
review. To this end, EPA proposes to add clarity around what will be 
peer reviewed. The 2017 final rule stated that ``the risk evaluation'' 
will be peer reviewed. The proposed regulatory text at Sec.  702.41 
provides EPA's expectation that peer review activities could be 
conducted on risk evaluations ``or portions thereof.'' EPA believes 
this provides the needed flexibility to conserve Agency resources and 
avoid redundant peer review. EPA requests comments on the proposed 
changes with respect to peer review, including whether the proposed 
addition of ``or portions thereof'' is consistent with OMB and Agency 
guidance.
    Consistent with the 2017 proposed and final rules, EPA will not 
seek peer review of any determination as to whether the risk is 
``unreasonable,'' which is an Agency policy determination. Consistent 
with OMB and EPA guidance, the purpose of peer review is the 
independent review of the science underlying the TSCA 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)). This is 
consistent with the statutory purpose of the SACC, ``to provide 
independent advice and expert consultation, at the request of the 
Administrator, with respect to the scientific and technical aspects of 
issues relating to the implementation of this title'' (15 U.S.C. 
2625(o)(2)).

I. Scientific Standards

    TSCA section 6(h) and (i) require the Agency to make decisions 
under TSCA section 6 in a manner that is consistent with the best 
available science and based on the weight of scientific evidence. 
Specifically, TSCA section 26(h) requires that in carrying out TSCA 
sections 4, 5, and 6, to the extent the Agency makes decisions based on 
science, the Agency shall ``use scientific information, technical 
procedures, measures, methods, protocols, methodologies, or models, 
employed in a manner consistent with the best available science.'' The 
statute then lists considerations: (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. Section 26(i) 
states ``the Administrator shall make decisions under sections 4, 5, 
and 6 based on the weight of scientific evidence.'' TSCA does not 
define either ``best available science'' or ``weight of scientific 
evidence'' and there is no requirement in the statute to define them by 
rule. Codification of definitions has potentially broader impacts 
beyond TSCA section 6 risk evaluations and rules, including TSCA 
sections 4 and 5 actions, and potentially other applications outside of 
TSCA.
    EPA received significant comment about the codification of 
definitions for these terms during the development of the 2017 proposed 
rule (Ref. 1 and Ref. 44). Some commenters noted that it is imperative 
that the Agency have specific criteria which would allow for 
consistency and transparency for how EPA will implement science. Others 
argued that since interested persons may submit risk assessments to the 
Agency for consideration (under TSCA section 26(l)(5)), it is necessary 
for the Agency to provide a standard and expectation. Many commenters 
noted that there are a number of ways the Agency could and has defined 
these terms across other statutory obligations and suggested this could 
be both a reason to codify TSCA-specific definitions, or to not codify 
them to avoid future limitations in implementation approaches. Others 
have argued that the risk evaluation rule should be reserved for 
process and procedure, and that codification of

[[Page 74309]]

specific process definitions would limit the Agency's ability to adapt 
to the changing science of risk evaluation, as well as the science that 
informs risk evaluation. Further, some argued that defining the terms 
would limit the flexibility afforded the Agency, and arguably the 
mandate, to implement and advance novel science.
    EPA determined not to propose codifying definitions of either of 
these terms in the 2017 proposed rule (Ref. 9 at p. 7572), citing the 
need to remain flexible to changing science and approaches. The Agency 
argued at that time that further defining these terms was unnecessary 
and ultimately problematic. EPA noted that these terms have and will 
continue to evolve with changing scientific methods and innovation, and 
Agency guidance does and will provide the necessary description and 
processes to ensure consistency and transparency (Ref. 9 at p. 7572). 
Ultimately, EPA did codify definitions for both of these terms in the 
final rule, explaining that codification of these definitions would 
instill confidence, increase transparency, predictability, and provide 
the public with assurance that EPA will adhere to the requirements of 
the statute (Ref. 1 at p. 33731). EPA is proposing to eliminate the 
following definitions from the regulatory text for the reasons 
described in Units III.H.1. and 2.
1. Best Available Science
    In the 2017 final risk evaluation rule, the Agency defined best 
available science as science that is reliable and unbiased, and 
described the use of best available science as involving 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). The definition also identified 
other considerations as applicable, including 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;
     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 variability and uncertainty in the information, or in 
the procedures, measures, methods, protocols, methodologies, or models, 
are evaluated and characterized; and
     There is independent verification or peer review of the 
information or of the procedures, measures, methods, protocols, 
methodologies or models.
    In general, EPA continues to believe this current definition of 
``best available science'' is aligned with the Agency's views and the 
science requirements in TSCA section 26(h). The first part of this 
definition originated from the Safe Drinking Water Act (SDWA) (42 
U.S.C. 300f et seq.) (Ref. 45), and second part of the definition is 
drawn verbatim from the considerations listed in TSCA section 26(h)(1) 
through (5). SDWA adopted a basic standard of quality for the use of 
science in agency decision making. Under 42 U.S.C. 300g-1(b)(3)(A), the 
Agency is directed, ``to the degree that an Agency action is based on 
science,'' to use ``(i) the best available, peer-reviewed science and 
supporting studies conducted in accordance with sound and objective 
scientific practices; and (ii) 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).'' The mandate to use the 
best available science with considerations enumerated in TSCA section 
26(h) closely mirrors these requirements. Specifically, TSCA section 
26(h)(5) refers to verified and peer reviewed science and scientific 
methods, and TSCA sections 26(h)(1) though (4) refer to the important 
considerations for the Agency when identifying and using data in a risk 
evaluation. This further comports with SDWA's quality standard for the 
dissemination of public information about risks of adverse health 
effects (42 U.S.C. 300g-1(b)(3)(B)).
    The precedent-setting standards in SDWA are further discussed in 
the OMB Information Quality Guidelines. These guidelines ``provide 
policy and procedural guidance to Federal agencies for ensuring and 
maximizing the quality, objectivity, utility, and integrity of 
information (including statistical information) disseminated by Federal 
agencies'' (Pub. L. 106-554; 114 Stat. 2763A-153 through 2763A-154). 
The Guidelines for Ensuring and Maximizing the Quality, Objectivity, 
Utility, and Integrity, of Information Disseminated by the 
Environmental Protection Agency (Ref. 46, also referred to as EPA's 
Information Quality Guidelines) contain EPA's policy and procedural 
guidance for ensuring and maximizing the quality of information 
disseminated in Agency work products. Section 6.4 of EPA's Information 
Quality Guidelines discuss how the Agency ensures and maximizes the 
quality of information used in risk assessment and specifically adopts 
the SDWA quality principles. EPA's Information Quality Guidelines go on 
to say: ``In applying these principles, `best available' usually refers 
to the availability at the time an assessment is made. However, EPA 
also recognizes that scientific knowledge about chemical risk is 
rapidly changing and that risk information may need to be updated over 
time.'' In general, EPA believes the SDWA definition of ``best 
available science'' and the associated guidelines and policies are all 
aligned with the science requirements enumerated in TSCA section 26(h).
    However, EPA believes that codifying a definition of ``best 
available science'' in the Risk Evaluation procedural rule is 
unnecessary and potentially problematic as it could limit the Agency's 
ability, flexibility, and mandate to incorporate the best available 
science into TSCA risk evaluations. As such, EPA is proposing to 
eliminate the definition of ``best available science'' from Sec.  
702.33. EPA specifically requests public comment on the proposed 
elimination of the definitions, the need for such definitions, and the 
utility of definitions as the state of science evolves. As discussed 
previously, EPA believes the specifics of that definition are already 
reflected in the TSCA requirements and considerations for applying the 
best available science in section 26(h), and in the Agency's policies 
and procedural guidance. These considerations are also replicated in 
the proposed regulatory text at Sec.  702.37(a)(2). The Agency does not 
believe codifying a definition of ``best available science'' provides 
any additional transparency or improves consistency.
    Furthermore, while the use and consideration of ``best available 
science'' is discussed at length in both EPA and other Federal agency 
guidance documents, the definition is not codified in other Agency 
rulemakings. EPA believes that a specific definition should not be 
codified in this rulemaking. Under proposed Sec.  702.37(a)(1), the 
Agency would use appropriate Agency guidance in the development of the 
TSCA risk evaluations. TSCA section 26(l) requires the Agency to use 
and develop guidance documents that are necessary in carrying out the 
statute. TSCA further requires the revisions of guidance

[[Page 74310]]

documents as necessary to ``reflect new scientific developments and 
understandings.'' Reliance on Agency guidance for determining the 
``best available science'' in TSCA risk evaluations ensures the desired 
transparency and consistency, while still allowing for more nimble 
adaptation over time.
    As the Agency identifies reasonably available information to inform 
a TSCA risk evaluation of a given chemical, EPA may consider existing 
risk assessments, or reviews performed on the chemical in question to 
be the best available science. This may include assessments conducted 
by EPA that adhere to existing Agency Guidance, use methodologies that 
have been externally peer reviewed, and undergo public comment. 
Similarly, the Agency may also look to consider assessments or portions 
of assessments conducted by other United States or international 
authoritative bodies. EPA may consider these existing assessments or 
reviews to represent the best available science as required under TSCA 
and use portions of them to directly inform a risk evaluation.
2. Systematic Review and Fit-for-Purpose Systematic Approaches
    The 2017 final risk evaluation rule defined weight of scientific 
evidence (WOSE) as used in TSCA to include the use of a ``systematic 
review method'' with a ``pre-established protocol'' to ``identify and 
evaluate each stream of evidence.'' In turn, in implementation of this 
regulatory requirement, EPA has previously viewed this definition as 
requiring the Agency to conduct systematic review according to a 
protocol on each evidence stream. The first method used was the 2018 
Application of Systematic Review in TSCA Risk Evaluations (Ref. 47). 
This method was reviewed by the National Academies of Science, 
Engineering, and Medicine (NASEM) and the study report published in 
2021, The Use of Systematic Review in EPA's Toxic Substances Control 
Act Risk Evaluations (Ref. 48), included several opportunities and 
recommendations to improve EPA's systematic review process. In response 
to recommendations made by the NASEM, as well as comments received from 
the TSCA SACC and the public during the review of the first ten risk 
evaluations, EPA significantly updated the TSCA systematic review 
process and developed a systematic review protocol. The draft TSCA 
Systematic Review Protocol (Ref. 49) replaced the Application of 
Systematic Review in TSCA Risk Evaluations. As described in Unit 
III.I.3., EPA is proposing changes to the WOSE definition to ensure 
that the concepts and principles of systematic review and WOSE are used 
in the evaluation of existing chemicals and are appropriately 
considered separately.
    TSCA risk evaluations use reasonably available information to draw 
the conclusions that are supported by the best available science. 
Reasonably available information is identified and evaluated through 
unbiased, transparent and objective data collection and data 
evaluation, using systematic review methods. EPA believes that 
integrating appropriate and applicable systematic review methods and 
approaches into the TSCA risk evaluations are critical to meet the 
scientific standards as described in TSCA section 26(h). A systematic 
review approach to data collection and data evaluation provides more 
complete information than an informal or unstructured review and can 
reduce bias in data selection (Ref. 49). The principles of systematic 
review collection and evaluation of data and information have been well 
developed in the context of evidence-based medicine (e.g., evaluating 
efficacy in clinical trials) and more recently have been adapted for 
use across a more diverse array of scientific fields. A 2014 report by 
the National Research Council (NRC) describes systematic review as ``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'' (Ref. 50). 
There are also well-established principles of systematic review like 
``transparent and explicitly documented methods, consistent and 
critical evaluation of all relevant literature, application of a 
standardized approach for grading the strength of evidence, and clear 
and consistent summative language'' (Ref. 50). Systematic review 
includes performing--as described and documented in a protocol--a 
methodical literature search, collection and screening, followed by 
data quality evaluation (addressing factors such as relevancy and 
bias), extraction, and integration, using a defined protocol, that can 
be applied across multiple lines of evidence. Any systemic approach EPA 
uses will follow this process.
    The TSCA program will also continue to work with partners including 
EPA's Office of Research and Development (ORD), the Office of Pesticide 
Programs, and the Office of Water (OW) to advance and implement tools, 
methods, and efficiencies to systematically collect and evaluate 
literature. The procedures required for ensuring objectivity, 
transparency and no bias in the collection and review of data for TSCA 
risk evaluations must be flexible enough to account for the diversity 
of both hazard and exposure information necessary to inform TSCA risk 
evaluations, and implementable within the statutory deadlines. EPA will 
continue to develop and evolve its systematic approaches to data 
collection and evaluation for use in TSCA risk evaluations to meet 
these goals. EPA will continue to use the principles and tools outlined 
in the draft TSCA Systematic Review Protocol (Ref. 49), but the Agency 
will move to implement more chemical specific approaches that are more 
flexible and relevant for the types and quantity of information used in 
an individual risk evaluation. As such, systemic review approaches must 
be commensurate with the relevant complexity of the assessment and 
nature of the information available, and carried out in a manner that 
permits completion within the timeframes that Congress provided. EPA 
will look to streamline chemical-specific protocols and approaches 
while remaining consistent with systematic review principles. These 
systematic approaches will be transparent, fit-for-purpose, and 
specific to the needs of each chemical/category, while better aligning 
with the schedules for completion of the risk evaluation. The Agency is 
also exploring how to leverage consideration of systematic reviews and 
systematic review approaches from other EPA offices and authoritative 
bodies, or portions thereof, to achieve greater efficiencies in the 
process. Ultimately, application of systematic review and/or systematic 
approaches are necessary to help EPA identify useful evidence, inform 
judgments as to the ``best available science'' and ``weight of 
scientific evidence'' (WOSE), and can transparently support risk 
evaluations that are both scientifically robust and defensible.
3. Weight of Scientific Evidence
    In the 2017 Final Rule, EPA defined the WOSE as ``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.'' 40 CFR 702.33. The Agency 
believes this definition is problematic and inconsistent with typical 
risk assessment practice and is therefore proposing to eliminate the 
definition

[[Page 74311]]

from the regulatory text--instead relying on long-established Agency 
guidance documents to guide weight of scientific evidence analyses 
under TSCA.
    The 2017 final rule conflates WOSE (also referred to as weight of 
evidence (WOE)) and systematic review. This conflation was identified 
and best described by NASEM's review of EPA's publication titled 
Application of Systematic Review in TSCA Risk Evaluations (Ref. 47). In 
their study report, The Use of Systematic Review in EPA's Toxic 
Substances Control Act Risk Evaluations (Ref. 48), the NASEM reviewers 
state ``this definition of WOE seems to say that the TSCA systematic 
review is itself a WOE evaluation. As such, the agency's legal 
obligation to conduct a WOE evaluation is fulfilled by the fact that 
systematic review is the basis for TSCA evaluations.'' The NASEM 
Committee goes further describing the confusion that results when the 
WOSE is used at one stage of the systematic review process to integrate 
the strength of the evidence judgment for each individual evidence 
stream into an overall conclusion for a health endpoint, whereas under 
the WOSE definition, the systematic review process itself is a weight 
of scientific evidence evaluation (Ref. 48). Throughout the report, the 
Committee notes the conflation of terms and goes on to suggest that 
changing the definition of WOSE within the risk evaluation procedural 
rule may alleviate the terminology confusion (Ref. 48).
    In developing this proposed rule, the Agency reviewed several 
alternative definitions or descriptions of WOSE or WOE. It is clear 
there are certain principles of WOSE that are universal, including 
foundational considerations such as objectivity and transparency. The 
phrase WOSE or WOE is used by EPA and other scientific bodies to 
describe the strength of the scientific inferences that can be drawn 
from a given body of evidence, specifically referring to the quality of 
the studies evaluated, and how findings are assessed and integrated. 
EPA broadly uses the WOSE approach in many existing programs and has 
described the application of WOSE in Agency guidelines used to classify 
carcinogens. In the 2005 Guidelines for Carcinogen Risk Assessment 
(Ref. 37), EPA refers to the WOE approach as ``. . . a collective 
evaluation of all pertinent information so that the full impact of 
biological plausibility and coherence is adequately considered.'' The 
Endocrine Disruptor Screening and Testing Advisory Committee (EDSTAC) 
referred to the WOE approach as ``. . . a process by which trained 
professionals judge the strengths and weaknesses of a collection of 
information to render an overall conclusion that may not be evident 
from consideration of the individual data'' (Ref. 51). EPA believes 
WOSE inherently involves application of professional judgment, in which 
the significant issues, strengths, limitations of the data, 
uncertainties, and interpretations are presented and highlighted.
    As noted by the National Academies of Science, ``because scientific 
evidence used in WOE evaluations varies greatly among chemicals and 
other hazardous agents in type, quantity, and quality, it is not 
possible to describe the WOE evaluation in other than relatively 
general terms'' (Ref. 23). EPA does not believe that even an 
alternative codified definition would add additional transparency or 
certainty to the required use of WOSE in TSCA risk evaluations. 
Additionally, the Agency believes that codifying a specific definition 
would inhibit the flexibility of the Agency to quickly adopt and 
implement changing science to ensure that each risk evaluation is fit-
for-purpose to the chemical under review. As such, EPA is proposing to 
remove the current codified definition of weight of scientific 
evidence. The Agency welcomes comment on this approach.
    EPA will instead rely on established Agency guidance documents to 
guide the required application of WOSE in TSCA risk evaluations. At 
this time, EPA will primarily look to four documents for implementing 
WOSE in TSCA risk evaluations: 2016 Weight of Evidence in Ecological 
Assessment (Ref. 52), Guidelines for Carcinogen Risk Assessment (Ref. 
37), 2011 Endocrine Disruptor Screening Program Weight-of-Evidence: 
Evaluating Results of EDSP Tier 1 Screening to Identify the Need for 
Tier 2 Testing (Ref. 53), and 2022 ORD Staff Handbook for Developing 
IRIS Assessments (Ref. 54). These documents all similarly describe the 
WOSE assessment as based on the strengths, limitations, and 
interpretation of data available, information across multiples lines of 
evidence and how these different lines of evidence may or may not fit 
together in drawing conclusions. The results from the scientifically 
relevant published or publicly available peer-reviewed studies, gray 
literature, or any other studies or lines of evidence which are of 
sufficient quality and reliability, are evaluated across studies and 
endpoints into an overall assessment. WOSE assessments examine multiple 
lines of evidence considering a number of factors, including for 
example the nature of the effects within and across studies, including 
number, type, and severity/magnitude of effects and strengths and 
limitations of the information. A summary WOSE narrative or 
characterization accompanies the detailed analysis and is intended to 
transparently describe the conclusion(s) and reasoning behind it/them. 
Specifically, the narrative or characterization generally explains the 
selection of the studies or effects used as the main lines of evidence 
and relevant basis for conclusions, and describes the overall strength 
of the evidence supporting a conclusion from the WOSE assessment.

J. Process for EPA Revisions To Scope or Risk Evaluation Documents

    EPA is proposing some new procedures and criteria for whether and 
how EPA would endeavor to revise or supplement final scope documents, 
and draft or final risk evaluations. The 2017 final rule does not 
provide any such criteria or procedures. The proposed procedures 
provide greater certainty and transparency for stakeholders. 
Additionally, given the tens of thousands of existing chemical 
substances in commerce and EPA's responsibility to assess and manage 
risks from those chemicals through a statutory deadline-driven pipeline 
of prioritization, risk evaluation and risk management activities, EPA 
believes that some guardrails are necessary to ensure that the Agency 
continues to make forward progress on existing chemicals as Congress 
intended. Continuously revisiting final risk evaluations would drain 
the Agency's already limited resources and divert attention from other 
chemicals actively in the prioritization, risk evaluation or risk 
management phases. The criteria and procedures in this proposed rule 
would serve the law's purpose to move chemicals through the process 
within the statutory deadlines, and allow the Agency to move on to 
evaluating another high-priority substance, consistent with TSCA 
section 6(b)(3)(C).
    Specifically, with respect to final scope documents, EPA is 
proposing that subsequent changes--if any--to the scope of the risk 
evaluation after publication of the final scope be reflected and 
described in the draft risk evaluation instead of a revised final scope 
document. EPA believes that, moving forward, any changes to the scope 
of the risk evaluation after publication of a final scope document are 
likely to be minimal based on the improved processes proposed in this 
NPRM, and EPA's expected rulemaking to implement a tiered data 
collection strategy to better inform data needs for prioritization and 
risk evaluation

[[Page 74312]]

candidates (Ref 57). However, in the event that changes to the risk 
evaluation scope during that period are more significant, EPA 
recognizes that public notice of those changes might be warranted. The 
proposal contemplates that EPA could, in its discretion, publish a 
notice in the Federal Register notifying the public that EPA has made 
information regarding changes to the risk evaluation scope available in 
the docket before releasing the draft risk evaluation.
    Likewise, EPA is proposing to refrain from reissuing draft risk 
evaluations in a second draft form. Draft documents are, by their 
nature, subject to change. Rather than spending time and resources to 
develop and issue a revised draft risk evaluation, EPA instead expects 
to reflect and describe any changes to the draft document in the final 
risk evaluation. Where changes from draft to final are significant in 
nature, nothing in the proposed rule would prevent EPA from seeking 
additional advice or feedback from its independent scientific advisors 
or additional public comment on relevant topics, provided that such 
actions can be completed within the timeframes Congress contemplated 
for TSCA risk evaluations. This proposed clarification to the Agency's 
process ensures that feedback is appropriately considered and reflected 
without unduly delaying progress towards completion of the risk 
evaluation.
    EPA is proposing a general practice for how and when to revisit 
final risk evaluations, and certain exceptions to that practice. As 
general practice, where circumstances warrant revisiting a chemical 
risk evaluation that has already been finalized--which EPA believes are 
likely to be infrequent--the Agency may identify that chemical as a 
potential candidate for high-priority designation, and follow the 
procedures at 40 CFR part 702, subpart A. EPA believes that this 
general practice aligns with Congress' intent for the Agency to work 
systematically through the universe of existing chemicals within the 
statutory framework and aggressive deadlines associated with 
prioritization, risk evaluation and risk management. (15 U.S.C. 
2605(b)(2)(C) and (b)(4)(G)). Revisiting risk evaluations outside of 
re-prioritizing the chemical substance results in unanticipated and 
potentially unbudgeted work that can siphon resources from statutorily 
mandated responsibilities under TSCA section 6. Conversely, re-
prioritizing the chemical provides the public with ample notice and 
opportunity to engage, provides anticipatable milestones and process, 
and better positions the Agency to maintain a manageable workload.
    Nevertheless, there may be certain circumstances where revisions to 
a final risk evaluation outside of re-prioritization of a chemical are 
in the interest of protecting human health and the environment. For 
example, as announced on June 30, 2021, EPA is revisiting the first 10 
final risk evaluations to ensure they followed the science and EPA's 
renewed understanding of the law, and determined a path forward on a 
case-specific, chemical-by-chemical basis (Ref. 7). The outcome of 
those risk evaluations, which may have underestimated risks based on, 
among other things, policies of excluding certain conditions of use and 
entire exposure pathways from assessment, warranted this action. 
Although changes proposed in this NPRM should prevent the types of 
issues that justified reanalysis of the first ten chemical risk 
evaluations, the same principle--the need to revise a final risk 
evaluation to protect human health and the environment--might apply to, 
for example, a scientific error that meaningfully impacts the 
evaluation or the Agency's ability to appropriately address risks 
through rulemaking.
    Where EPA endeavors to revise or supplement a final risk evaluation 
outside of re-prioritization, the proposed rule further requires EPA to 
follow the same process and requirements for TSCA risk evaluations 
described in this proposed rule, including publication of a new draft 
and final risk evaluation, solicitation of public comment, and, as 
appropriate, peer review.

K. Process and Requirements for Manufacturer-Requested Risk Evaluations

    EPA is proposing a number of changes to the process and 
requirements for manufacturers to request a risk evaluation. TSCA 
section 6(b)(4)(C)(ii) allows a manufacturer or group of manufacturers 
to request that the Agency conduct a risk evaluation of a chemical 
substance (or category of substances) that they manufacture. TSCA 
section 6(b)(4)(C)(ii) directs EPA to establish the ``form . . . manner 
and . . . criteria'' for such requests by rule, which the Agency 
finalized in 2017. Based on experience in implementing that process to 
date, EPA is proposing some modifications to increase clarity and to 
better position the Agency to carry out manufacturer-requested risk 
evaluations (MRREs) moving forward.
    The current process for MRREs, laid out in 40 CFR 702.37, has been 
challenging for EPA in a number of ways. First, the 2017 final rule 
allows requests to contain information relevant only to conditions of 
use of the chemical that are of interest to the requesting manufacturer 
(40 CFR 702.37(b)(3)). Within a relatively short time after receiving a 
request, EPA must either grant or deny the request (40 CFR 
702.37(e)(6)). By ``granting'' an MRRE request under the current 
regulations, EPA is acknowledging that it has all the information it 
needs to conduct the evaluation, creating some ambiguity as to whether 
additional information can be gathered during the process, including 
through use of EPA's TSCA section 4 or 8 authorities. The process 
effectively leaves the Agency with the heavy burden of identifying the 
remaining conditions of use, reviewing information that came in with 
the request, obtaining and reviewing additional available literature, 
and determining any missing information or data needs--all within a 
matter of months. The current process also provides that upon granting 
the request, EPA will initiate the risk evaluation, triggering the 
start of the three-year statutory deadline to complete the activity (40 
CFR 702.37(e)(10)).
    EPA has found that this process is unrealistic. In addition to 
needing more fulsome information included in incoming requests, and 
additional time to properly review requests and determine any 
additional information needs prior to initiating the evaluation, EPA 
also needs some flexibility in the process to pursue data collection or 
development during the risk evaluation. In general, EPA believes that 
the process and timeframes for reviewing incoming MRRE requests should 
be more akin to the process and timeframes that precede EPA-initiated 
risk evaluations. When considering whether a chemical is a good 
potential candidate for prioritization--including the chemical's 
readiness for evaluation from a data perspective--EPA has a significant 
amount of time to review and analyze available information, identify 
data gaps and needs, and pursue various data gathering strategies. On 
top of that, the prioritization process itself provides an additional 9 
to 12 months and two 90-day public comment periods to help the Agency 
refine its approach and deepen its understanding of the chemical--all 
before initiating the risk evaluation and the associated deadlines.
    The proposed rule is intended to address these challenges. Units 
III.K.1. through 4. Describe the key proposed changes to the process 
for MRREs, and EPA's expectations for implementation moving forward:

[[Page 74313]]

1. Submission of MRRE
    The law allows for submission of a MRRE by one or more 
manufacturers of a chemical substance, and both the current and 
proposed rule maintain that requirement as part of the regulatory text. 
However, in cases where multiple manufacturers jointly submit a MRRE 
(i.e., a consortium), EPA expects to treat a consortium as a single 
entity for purposes of any regulatory determinations with regard to the 
requests, fee payments, and other general communication regarding the 
MRRE request and/or the risk evaluation. Joint submitters must 
designate a single point of contact for Agency engagement, and are 
otherwise collectively responsible for providing complete and 
sufficient information to the Agency to support the risk evaluation.
2. Scope of Request
    Currently, the rule allows manufacturers to request a risk 
evaluation on particular conditions of use of interest, leaving the 
Agency with the heavy burden of identifying the remaining conditions of 
use. EPA is proposing that manufacturers only be permitted to make 
requests for evaluations of entire chemical substances--not individual 
conditions of use or subsets of conditions of use. In addition to 
better aligning with the statutory language in TSCA section 6(b)(4)(C) 
(stating that EPA ``shall conduct and publish risk evaluations . . . on 
a chemical substance . . .'') and the scope of EPA-initiated risk 
evaluations, EPA believes this clarification will also encourage more 
robust, well-crafted submissions and better position the Agency for 
success in carrying out the evaluations. EPA recognizes that a 
requesting manufacturer may not have access to all necessary 
information to support the risk evaluation, and, as described in Unit 
III.K.4, EPA is also proposing a process to address these shortcomings. 
However, the proposed clarification regarding scope--along with changes 
described in Unit III.K.3.--would ensure no misgivings about the scope 
of MRREs and the information needed to support those requests in order 
for the Agency to undertake a risk evaluation.
3. Contents of Request
    EPA is also proposing some key changes to the supporting 
information that must be included in a MRRE request. As a general 
matter, EPA believes that the requesting manufacturer(s) should bear 
the primary burden of providing EPA with all information necessary to 
conduct a risk evaluation on the chemical substance. Congress also 
shared this sentiment in section 2 of TSCA, stating that ``adequate 
information should be developed with respect to the effect of chemical 
substances and mixtures on health and the environment and that the 
development of such information should be the responsibility of those 
who manufacture and those who process such chemical substances and 
mixtures.'' 15 U.S.C. 2601(b). Within respect to MRRE requests, 
Congress authorized EPA to establish the ``form . . . manner and . . . 
criteria'' for such requests in order to support successful 
implementation. (15 U.S.C. 2605(b)(4)(C)). The 2017 final rule's 
allowance for the requesting manufacturer(s) to only provide supporting 
information relevant to their preferred conditions of use 
inappropriately shifts much of the information gathering burden to the 
Agency. Instead, EPA believes, as discussed in Unit III.K.2., based on 
TSCA's statutory text and structure, that MRRE requests should attempt 
to identify all intended, known and reasonably foreseen circumstances 
of the chemical's manufacture, processing, distribution in commerce, 
use and disposal, and provide all available information regarding the 
chemical's hazards and exposures--not just information of relevance to 
the submitter's interests. As such, EPA is proposing changes that would 
require more fulsome information as part of the request, based on 
information that is known to or reasonably ascertainable by the 
requesting manufacturer.
    More specifically, EPA is proposing to require that manufacturers 
include a listing of the chemical's conditions of use (i.e., the 
circumstances under which the chemical substance is intended, known, or 
reasonably foreseen to be manufactured, processed, distributed in 
commerce, used, or disposed of), and all information known to or 
reasonably ascertainable by the requesting manufacturer that supports 
the identification of those circumstances. While EPA must ultimately 
determine the chemical's conditions of use for purposes of the risk 
evaluation, this requirement ensures a reasonable level of due 
diligence on the part of the requesting manufacturer to gather 
available information and provide it to EPA. Similarly, EPA is also 
proposing that incoming requests include ``all information known to or 
reasonably ascertainable by the requesting manufacturer on the health 
and environmental hazard(s) of the chemical substance, human and 
environmental exposure(s), and exposed population(s).'' The proposed 
rule also provides some clarifications as to the specific types of 
information that must be included as part of the request. Under the 
2017 final rule, requesting manufacturers are required to provide this 
information only where relevant to the particular uses of interest, 
leaving EPA with significant work not just to identify the remaining 
conditions of use, but also to locate and review available literature 
and quickly determine whether there is sufficient information to carry 
out a risk evaluation. The proposed changes put more of this 
responsibility on the requesting manufacturer. EPA believes that 
requesting manufacturers should be making a reasonable amount of effort 
to gather all available information on the chemical--whether that 
information is available to the general public, or otherwise available 
to the manufacturer--and compile it for the Agency's review as part of 
an MRRE.
    Information that is known to or reasonably ascertainable by the 
manufacturer would include all information in a person's possession or 
control, plus all information that a reasonable person similarly 
situated might be expected to possess, control, or know. The standard 
requires an exercise of due diligence, and the specific information-
gathering activities that may be necessary for manufacturers to achieve 
this standard may vary from case-to-case. In the context of preparing a 
MRRE request and to meet the requirements in the proposed rule at Sec.  
702.45(c), EPA believes that due diligence would, at a minimum, involve 
a thorough search and collection of publicly available information on 
the chemical's hazards, exposures and conditions of use. EPA would 
further expect that requesting manufacturers conduct a reasonable 
inquiry not only within the full scope of their organization regarding 
manufacturing processes and products (including imports), but also 
outside of their organization to fill gaps in knowledge. For example, 
such activities might include inquiries to upstream suppliers or 
downstream users or employees or other agents of the manufacturer, 
including persons involved in the research and development, import or 
production, or marketing for information pertinent to the criteria 
listed in the proposed rule.
    EPA nonetheless still anticipates that manufacturers may not be in 
a position to provide the Agency with all the information necessary to 
complete the risk evaluation. EPA received comments

[[Page 74314]]

on the original 2017 proposed rule, for example, that manufacturers who 
do not produce the chemical for a particular use may not be able to 
obtain information pertaining to that use. To address this issue, EPA 
is proposing a process described further in Unit III.K.4. to formalize 
how such shortcomings will be identified and addressed. In short, where 
the requesting manufacturer is unable to provide all the information 
EPA needs for risk evaluation, the requesting manufacturer can request 
EPA use its information collection authorities under TSCA sections 4 
(require manufacturers (including importers) or processors to test 
chemicals and report their findings), 8 (require reporting on chemical 
manufacturing, processing, and use, or require the submission of 
unpublished chemical health and safety information from manufactures 
(including importers), processors, or distributors), or 11 (ability to 
inspect facilities where chemicals are manufactured, processed, stored, 
or held before or after their distribution in commerce), to fill in the 
gaps. Where the information need is identified after the risk 
evaluation has already been initiated, the requesting manufacturer must 
also suspend its request to allow sufficient time for the Agency to 
exercise those authorities. These changes set clearer expectations for 
what EPA needs to undertake in a risk evaluation, and establish a 
process for productive engagement with requesting manufacturers toward 
meeting those needs.
4. EPA Process for Reviewing Requests
    EPA is proposing a number of changes to how the Agency will review 
MRREs. As described in this Unit, the current process simply does not 
allow enough time for thoughtful review of requests and consideration 
of potential information needs. As such, at Sec.  702.45(e) of the 
regulatory text, EPA is proposing changes to the steps the Agency will 
take upon receipt of a MRRE, including additional measures for 
transparency and public engagement. The following is a general 
description of the proposed procedural steps:
    Notice of Receipt. EPA will provide the public with notice within 
15 days that a MRRE has been received. Although the proposed rule does 
not specify the means of notice, EPA expects to generally do so through 
updates to its website and email listserv notifications.
    Initial Review for Completeness. EPA will then begin reviewing the 
request and supporting information against the requirements in the 
proposed rule to determine whether or not the request appears complete. 
Requests that are clearly missing key required information in Sec.  
702.45(c) or are otherwise not well-supported will be rejected and 
returned to the submitter as incomplete. For example, EPA would 
consider a request for evaluation of category of chemicals incomplete 
where the request does not provide a rationale as to why the 
categorization is appropriate under TSCA section 26(c). Likewise, where 
a request fails to describe the circumstances related to the full 
lifecycle of the chemical substance (i.e., manufacture, processing, 
distribution in commerce, use and disposal) or to provide an 
explanation as to why such information is unavailable to the requestor, 
EPA may reject the request as incomplete. During this step, EPA may 
also make an initial judgment as to the quality or quantity of 
information provided by the requesting manufacturer(s) and the 
sufficiency of that information to support a risk evaluation. Where the 
information is generally of poor quality, or when very little 
information is provided, EPA may also reject the request.
    This initial review step allows the Agency to screen incoming 
requests before advancing to the more time- and resource-intensive 
steps associated with reviewing a MRRE. Where EPA determines a request 
to be incomplete, the requesting manufacturer can simply supplement and 
resubmit the request. Where EPA initially determines the request to be 
complete, EPA will advance to the next step in the process: public 
notice and opportunity for comment.
    Public Notice and Comment. Where EPA initially determines the 
request to be complete, EPA will submit a notice of receipt of the MRRE 
for publication in the Federal Register within 90 days. EPA will also 
open a docket that includes all non-CBI and CBI-sanitized information 
included in the request and provide no less than a 60-day public 
comment period. EPA may also solicit specific comments on the request, 
including feedback on the conditions of use listed by the manufacturer 
in the request and information regarding sufficiency of available 
information to support a risk evaluation.
    Secondary Review for Sufficiency. From the start of the public 
comment period, EPA would expect to begin conducting a more in-depth 
review of the request to determine whether there is sufficient 
information to support a reasoned evaluation on the chemical substance. 
Concurrently, EPA expects to conduct an internal cursory review of 
other reasonably available information, however more comprehensive 
information collection would occur post-granting of the request. For 
EPA-initiated risk evaluations, EPA has clearly indicated that it would 
not expect to initiate the prioritization process until there is 
sufficient information to complete both the prioritization and risk 
evaluation processes. Likewise, EPA would not expect to grant an MRRE 
until confident that there is a similar level of information to support 
evaluation. As described in the proposed rule, EPA may determine that 
certain information gaps can be addressed through application of 
assumptions, uncertainty factors, models, and/or screening, consistent 
with TSCA section 26, without the need for additional data. EPA's 
review during this period would encompass both the information provided 
with the request and any additional relevant information that may be 
uniquely available to EPA (e.g., TSCA CBI data that may not otherwise 
be known to or reasonably ascertainable by the requesting 
manufacturer). Following the close of the public comment period, EPA 
will further consider feedback from the public as to the sufficiency of 
available information. For example, if public comments indicate there 
are additional conditions of use, and the request does not identify or 
provide information relevant to those conditions of use, EPA may deem 
the request insufficient and return to the submitter for further 
consideration and possible supplementation.
    EPA may also determine during this period whether there are 
deficiencies in the request, including data quality considerations, not 
identified during EPA's initial review for completeness. EPA's review 
for sufficiency will be completed within 90 days from the end of the 
public comment period. For requests determined not to be supported by 
sufficient information during this period, EPA will reject the 
request--effectively ending the Agency's review--and notify the 
requesting manufacturer. EPA generally expects to keep the public 
apprised of the status of requests through updates to its website. The 
requesting manufacturer would have the opportunity to further 
supplement and resubmit their request to EPA. Additionally, where the 
submitter believes that the information is not reasonably ascertainable 
by them, they can include in their resubmission a request--as described 
in this Unit--that EPA exercise its information gathering authorities 
to collect and/or develop information necessary to remedy the 
deficiency. For requests

[[Page 74315]]

determined to be supported by sufficient information, EPA will proceed 
with granting the request and continuing the review process.
    Grant. As described elsewhere in this Unit III.K.4., and subject to 
the percentage limitations in TSCA section 6(b)(4)(E)(i)(II), EPA will 
grant MRRE requests that are both complete and supported by sufficient 
information. Under the 2017 final rule, a ``grant'' of a MRRE request 
effectively means that EPA has determined it has all information needed 
to conduct such risk evaluation. While EPA intends to make every effort 
to ensure sufficient information before granting a MRRE request, 
absolute certainty is not possible. Given the nature of risk assessment 
and public processes associated with TSCA risk evaluations, there may 
be occasion where EPA becomes aware of critical information needs later 
in the process. As such, the proposed rule specifically reserves the 
right for EPA to identify additional information needs for the risk 
evaluation at any time, including after granting the MRRE request.
    Publication of Draft Conditions of Use and Request for Information. 
EPA will next publish a notice in the Federal Register that sets out, 
in draft form, the Agency's preliminary determination on the chemical's 
conditions of use, taking into account information provided in the MRRE 
request, information received during the first public comment period, 
and EPA's own further review efforts. This notice will request relevant 
information from the public, and provide no less than a 60-day public 
comment period. Given that a chemical's conditions of use are such an 
important component to define the scope of the risk evaluation, EPA 
felt it was important to share its understanding and provide an 
opportunity for additional feedback before formally initiating the 
MRRE. In the context of EPA-initiated risk evaluations, EPA expects 
this engagement to occur during the prioritization process, and, 
similarly, before the formal initiation of the risk evaluation and 
start of the statutory deadline for completion. Within 90 days 
following the close of the public comment period in this paragraph, and 
depending on the nature of comments received, EPA will either initiate 
the risk evaluation or notify the requesting manufacturer of any 
additional information needs.
    Initiation of Risk Evaluation. Upon initiation of the MRRE, EPA 
will follow all requirements in this proposed rule including but not 
limited to proposed sections 702.37 through 702.49. EPA will notify the 
manufacturer that the MRRE has been initiated, and similarly expects to 
keep the public apprised of the status through updates to its website. 
As indicated previously, EPA is reserving the right to identify 
additional information needs at any time during the risk evaluation 
process, including post-initiation.
    Identification of Information Needs. Where additional information 
needs are identified at any time before the MRRE has been granted, the 
proposed rule provides a clear process for supplementation and 
resubmittal of the request. However, where additional information needs 
are identified at any point following EPA's grant of the MRRE, EPA will 
notify the requesting manufacturer(s) and set a reasonable amount of 
time, as determined by EPA, for manufacturers to respond to the 
Agency's notice. In response to EPA's notice, the manufacturer can 
choose to (1) provide the necessary information to EPA, (2) if the risk 
evaluation has not yet been initiated, withdraw the MRRE request, or 
(3) request that EPA obtain the information using authorities under 
TSCA sections 4, 8 or 11.
    Where a manufacturer chooses to provide--or develop and provide--
the necessary information, EPA will set a reasonable amount of time for 
the requesting manufacturer to provide that information to EPA. Upon 
receipt of the new information, EPA will review the information within 
90 days and determine whether or not it satisfies the identified need--
again providing notice to the requesting manufacturer of its 
determination, and keeping the public apprised of the status of the 
MRRE on its website. EPA would further endeavor, to the extent 
possible, to make the supplemental information publicly available in 
the docket.
    Alternatively, in the event the risk evaluation has not yet been 
initiated, the requesting manufacturer may withdraw the MRRE request. 
This option gives the requesting manufacturer some flexibility in the 
event that developing the necessary information would be considered too 
costly or time consuming. Any fees to be collected or refunded would be 
determined in accordance with this proposed rule and the TSCA fee 
provisions in 40 CFR 700.45. MRRE requests cannot be withdrawn by the 
requesting manufacturer once EPA has initiated the risk evaluation.
    Lastly, where the requesting manufacturer believes that they can 
neither collect nor develop the identified information, they may 
request that EPA obtain the information using its authorities under 
TSCA sections 4, 8 or 11. As part of such a request, the manufacturer 
must provide a rationale as to why the information is not reasonably 
ascertainable to them. EPA will review the request and provide notice 
of its determination to the requesting manufacturer as to whether or 
not use of these authorities is warranted. Where EPA agrees to use its 
authorities, EPA will review the new information within 90 days of 
receipt and determine whether or not it satisfies the identified need--
again providing notice to the requesting manufacturer and keeping the 
public apprised of the status of the MRRE on its website. EPA would 
further endeavor, to the extent possible, to make the supplemental 
information publicly available in the docket.
    EPA recognizes that Congress clearly intended for those requesting 
MRREs to cover either 50% or 100% of the costs to carry out the risk 
evaluation. See 15 U.S.C. 2625(b)(4)(D). However, in the event that EPA 
exercises its authorities to gather additional necessary information, 
costs may be imposed upon entities other than the requesting 
manufacturer. For example, if EPA issues a test order under TSCA 
section 4 to support a MRRE, another entity could have to pay both the 
test order fee as well as the costs of developing the information. 
While the costs to EPA would be reflected in the final invoice to the 
requesting manufacturer, EPA is seeking comment on, to the extent that 
test orders are issued to support a MRRE, whether EPA should amend the 
regulation to allow the entire test order fee to be directed to the 
requesting manufacturer, even where an order is issued to another 
entity who is not the requesting manufacturer.
    Unfulfilled Information Needs. EPA believes it is important that 
the procedures in this proposed rule account for a scenario in which 
information needs are not met, and the Agency is simply unable to 
complete the risk evaluation. In circumstances where EPA has identified 
additional data needs, but the requesting manufacturer(s) is unable or 
unwilling to fulfill those needs in a timely manner, has produced 
information that is insufficient to meet the need as determined by EPA, 
or where EPA determines that a request to use gather information under 
TSCA sections 4, 8 or 11 is not warranted (e.g., where the information 
is ascertainable by the manufacturer or the request does not provide a 
sufficient rationale), the proposed rule at Sec.  702.45(g) 
contemplates that EPA can deem the MRRE request to be constructively 
withdrawn (i.e., EPA would construe

[[Page 74316]]

the MRRE request to be withdrawn even in the absence of a request to 
withdraw). Any fees to be collected or refunded would be determined in 
accordance with this proposed rule and the TSCA fee provisions in 40 
CFR 700.45.
    Fees for MRRE will generally be determined in accordance with 40 
CFR 700.45. However, this proposed rule further specifies that in the 
event that a MRRE request is withdrawn after it has been granted--
either by the requesting manufacturer or constructively withdrawn by 
EPA--the total fee amount due will be either, in accordance with 40 CFR 
700.45(c)(2)(x) or (xi) (as applicable), 50% or 100% (respectively) of 
the actual costs expended in carrying out the risk evaluation as of the 
date of receipt of the withdrawal notice. The payment amount will be 
determined by EPA, and invoice or refund issued to the requesting 
manufacturer as appropriate.

IV. Requests for Comment

    EPA requests comment on all aspects of the proposed rule discussed 
in this Unit III., including comment on whether the proposed rule would 
enhance transparency and public understanding of EPA's TSCA risk 
evaluation process and better align with the 2016 amendments to TSCA 
under the Frank R. Lautenberg Chemical Safety for the 21st Century Act 
(Pub. L. 114-182, 130 Stat. 448). Additionally, within this proposal, 
the Agency is soliciting feedback from the public on specific issues 
throughout this proposed rule. For ease of review, this section 
summarizes those specific requests for comment.
    1. EPA requests comment on how the Agency could consider potential 
climate-related risks in a risk evaluation.
    2. EPA requests comment on the proposed approach of publishing a 
draft scoped during the prioritization process when it is clear that 
the chemical undergoing the prioritization process will be designated 
as a high-priority chemical.
    3. EPA requests public comment on the proposed elimination of the 
definitions of best available science and weight of scientific 
evidence, the need for such definitions, and the utility of definitions 
as the state of science evolves.
    4. EPA requests comments on the proposed changes to the process of 
a manufacturer requested risk evaluation. In regards to cost, while the 
costs to EPA would be reflected in the final invoice to the requesting 
manufacturer, EPA is seeking comment on, to the extent that test orders 
are issued to support a MRRE, whether the entire test order fee should 
also be directed to the requesting manufacturer, even where the order 
is also issued to another entity. Additionally, EPA requests specific 
comment on the burden estimate of a manufacturer requested risk 
evaluation, including the assumptions used in estimating the burden 
(e.g., number of requests EPA expects).
    5. EPA requests comment on general approaches or best practices for 
improving engagement with small entities. Early engagement with and 
feedback from all those who manufacture, process, distribute, use or 
dispose of a chemical is critical for the Agency to be able to 
accurately identify and characterize that chemical's conditions of use 
for consideration in the risk evaluation, EPA is seeking comment on how 
to improve its outreach to the stakeholder community, including 
education on the TSCA risk evaluation process for small entities.
    6. EPA requests public comment on how the Agency can provide a 
transparent and detailed basis for the proposed unreasonable risk 
determination and existing chemical exposure limits derived from the 
risk evaluation process.

V. Reliance Interests

    The proposed rule includes some statutory interpretations that 
differ from those previously held by the Agency at the time it issued 
the 2017 final rule, and, as part of developing this proposed rule, EPA 
has considered to what extent stakeholders may have reliance interests 
in those previous interpretations. EPA believes that there are either 
no reliance interests on those past statutory interpretations, or that 
any such interests are minor. The current rule and proposed changes 
largely pertain to internal Agency procedures that guide the Agency's 
risk evaluation activities under TSCA and mostly do not directly impact 
external parties, with one exception being modified procedural 
requirements for voluntary requests for risk evaluation submitted by 
manufacturers. However, to the extent there were any reliance interests 
on the prior interpretations, or the risk evaluations that were 
developed based on the previous procedural requirements, nothing in the 
proposed rule is intended to apply retroactively. EPA does not believe 
stakeholders have reliance interests pertaining to the process for 
future, yet-to-be-completed risk evaluations that will be carried out 
in accordance with this proposed rule.

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 itself physically located in the 
docket. For assistance in locating these other documents, please 
consult the person listed under FOR FURTHER INFORMATION CONTACT.

1. U.S. EPA. Procedures for Chemical Risk Evaluation Under the 
Amended Toxic Substances Control Act; Final Rule. Federal Register 
(82 FR 33726, July 20, 2017) (FRL-9964-38). https://www.govinfo.gov/content/pkg/FR-2017-07-20/pdf/2017-14337.pdf.
2. U.S. Court of Appeals for the Ninth Circuit. Safer Chemicals, 
Healthy Families v. USEPA, No. 17-72260 No. 17-72501 No. 17-72968 
No. 17-73290 No. 17-73383 No. 17-73390, Opinion. November 14, 2019. 
943 F.3d 397, 425-426. https://cdn.ca9.uscourts.gov/datastore/opinions/2019/11/14/17-72260.pdf.
3. Executive Order 13990. Protecting Public Health and the 
Environment and Restoring Science to Tackle the Climate Crisis. 
Federal Register (86 FR 7037, January 25, 2021). https://www.govinfo.gov/content/pkg/FR-2021-01-25/pdf/2021-01765.pdf.
4. U.S. EPA. Information Collection Request (ICR) for the Proposed 
Rule: Procedures for Chemical Risk Evaluation Under TSCA. EPA ICR 
No.: 2781.01 and OMB Control No. 2070-NEW.
5. Safer Chemicals, Healthy Families; et al., v. U.S. Environmental 
Protection Agency, No. 17-72260, 17-72501, 17-72968, 17-73290, 17-
73383, 17-73390, 2019 WL 6041996 (9th Cir. Nov. 14, 2019).
6. The White House, Briefing Room. Fact Sheet: List of Agency 
Actions for Review. January 20, 2021. https://www.whitehouse.gov/briefing-room/statements-releases/2021/01/20/fact-sheet-list-of-agency-actions-for-review/.
7. U.S. EPA. EPA Announces Path Forward for TSCA Chemical Risk 
Evaluations. Press Release. June 30, 2021. https://www.epa.gov/newsreleases/epa-announces-path-forward-tsca-chemical-risk-evaluations.
8. U.S. EPA. Assessing and Managing Chemicals under TSCA. Chemicals 
Undergoing Risk Evaluation under TSCA. https://www.epa.gov/assessing-and-managing-chemicals-under-tsca/chemicals-undergoing-risk-evaluation-under-tsca (Accessed May 31, 2023.)
9. U.S. EPA. Procedures for Chemical Risk Evaluation Under the 
Amended Toxic Substances; Proposed Rule. Federal Register. (82 FR 
7562, January 19, 2017) (FRL-9957-75). https://www.govinfo.gov/content/pkg/FR-2017-01-19/pdf/2017-01224.pdf.

[[Page 74317]]

10. U.S. EPA. Exposure Factors Handbook: 2011 Edition. EPA/600/R-
090/052F. Office of Research and Development, National Center for 
Environmental Assessment. Washington, DC. 2011. https://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=236252.
11. U.S. Senate Congressional Record, 162 Cong. Rec. S3511-01 (daily 
ed. June 7, 2016). https://www.congress.gov/114/crec/2016/06/07/CREC-2016-06-07-pt1-PgS3511.pdf.
12. U.S. EPA. Problem Formulation of the Risk Evaluation for 1,4-
Dioxane. EPA/740/R1/7012. Office of Chemical Safety and Pollution 
Prevention. Washington, DC. 2018. https://www.regulations.gov/document/EPA-HQ-OPPT-2016-0723-0064.
13. U.S. EPA. Risk Evaluation for Methylene Chloride 
(Dichloromethane, DCM) CASRN: 75-09-2. EPA-740-R1-8010. Office of 
Chemical Safety and Pollution Prevention. Washington, DC. 2020. 
https://www.regulations.gov/document/EPA-HQ-OPPT-2016-0742.
14. TSCA Science Advisory Committee on Chemicals. Peer Review for 
EPA Draft Risk Evaluation for Methylene Chloride. Meeting Minutes 
and Final Report No. 2020-1. March 2020. https://www.regulations.gov/document/EPA-HQ-OPPT-2019-0437-0080.
15. Comment from the Attorneys General of Massachusetts, California, 
Hawaii, Maine, Maryland, New Jersey, New York, Oregon, Vermont, 
Washington, and the District of Columbia. Comments submitted to EPA 
in response to Notice of Availability on Problem Formulations for 
the Risk Evaluations to be Conducted Under the Toxic Substances 
Control Act and General Guiding Principles to Apply Systematic 
Review in TSCA Risk Evaluations. https://www.regulations.gov/comment/EPA-HQ-OPPT-2016-0723-0074.
16. Safer Chemicals, Healthy Families et al. Comments submitted to 
EPA on Notice of Availability on Risk Evaluation Problem 
Formulations Documents for Ten Chemical Substances under the Toxic 
Substances Control Act. https://www.regulations.gov/docket/EPA-HQ-OPPT-2016-0723-0089.
17. U.S. EPA. Draft TSCA Screening Level Approach for Assessing 
Ambient Air and Water Exposures to Fenceline Communities Version 
1.0. EPA/744/D/22/001. Washington, DC. 2022. https://www.epa.gov/system/files/documents/2022-01/draft-fenceline-report_sacc.pdf.
18. Conference Committee Report on TSCA, Public Law 94-469, Senate 
Rep. No 94-1302 at 85 (1976) Conf Rep. https://www.congress.gov/bill/94th-congress/senate-bill/3149.
19. OSHA. Permissible Exposure Limits Annotated Tables. https://www.osha.gov/annotated-pels. (Accessed May 30, 2023).
20. U.S. EPA. General Principles for Performing Aggregate Exposure 
and Risk Assessment. Office of Pesticide Programs. November 28, 
2001. https://www.epa.gov/sites/default/files/2015-07/documents/aggregate.pdf.
21. NRC. Science and Judgment in Risk Assessment. The National 
Academies Press. Washington, DC. 1994. https://dx.doi.org/10.17226/2125.
22. NRC. Phthalates and Cumulative Risk Assessment: The Task Ahead. 
National Academies Press. Washington, DC. 2008. https://dx.doi.org/10.17226/12528.
23. NRC. Science and Decisions: Advancing Risk Assessment. National 
Academies Press. Washington, DC. 2009. https://dx.doi.org/10.17226/12209.
24. Food Quality Protection Act. 5.U.S.C. 136 et. seq.
25. U.S. EPA. Framework for Cumulative Risk Assessment. EPA/630/P-
02/001F. Risk Assessment Forum. Washington, DC. May 2003. https://www.epa.gov/sites/default/files/2014-11/documents/frmwrk_cum_risk_assmnt.pdf.
26. U.S. EPA. Guidelines for the Health Risk Assessment of Chemical 
Mixtures. Federal Register. (51 FR 34028, September 24, 1986) (FRL-
2984-3). https://www.govinfo.gov/content/pkg/FR-1986-09-24/pdf/FR-1986-09-24.pdf#page=158.
27. U.S. EPA. Supplementary Guidance for Conducting Health Risk 
Assessment of Chemical Mixtures. EPA/630/R-00/002.Risk Assessment 
Forum. Washington, DC. August 2000. https://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=20533.
28. U.S. EPA. Guidance on Cumulative Risk Assessment of Pesticide 
Chemicals That Have a Common Mechanism of Toxicity. Office of 
Pesticide Programs. Washington, DC. January 14, 2002. https://www.regulations.gov/document/EPA-HQ-OPP-2007-0797-0001.
29. U.S. EPA. Pesticide Cumulative Risk Assessment: Framework for 
Screening Analysis Purpose. Office of Chemical Safety and Pollution 
Prevention, Office of Pesticide Programs. Washington, DC. April 12, 
2016. https://www.regulations.gov/document/EPA-HQ-OPP-2015-0422-0019.
30. OECD. Considerations for assessing the risks of combined 
exposure to multiple chemicals (No. 558 296). In Series on Testing 
and Assessment No 296. Paris, France. 2018. https://dx.doi.org/10.1787/ceca15a9-en.
31. Meek, M.E.; Boobis, Alan R.; Crofton, Kevin M.; Heinemeyer, 
Gerhard; Van Raaij, Marcel; Vickers, Carolyn. Risk Assessment of 
Combined Exposure to Multiple Chemicals: A WHO/IPCS Framework. 
Regulatory Toxicology and Pharmacology. July 1, 2011. 60:S1-S14. 
https://dx.doi.org/10.1016/j.yrtph.2011.03.010.
32. U.S. EPA. Draft Proposed Principles of Cumulative Risk 
Assessment Under the Toxic Substances Control Act. EPA/740/P/23/001. 
Office of Chemical Safety and Pollution Prevention. Washington, DC. 
February 2023. https://www.regulations.gov/document/EPA-HQ-OPPT-2022-0918-0008.
33. U.S. EPA. Draft Proposed Approach for Cumulative Risk Assessment 
of High-Priority Phthalates and a Manufacturer Requested Phthalate 
Under the Toxic Substances Control Act Control Act. EPA/740/P/23/
002. Office of Chemical Safety and Pollution Prevention. Washington, 
DC. February 2023. https://www.regulations.gov/document/EPA-HQ-OPPT-2022-0918-0009.
34. U.S. EPA. Cumulative Impacts Research: Recommendations for EPA's 
Office of Research and Development. EPA 600/R-22/014a. Office of 
Research and Development. Washington, DC. September 30, 2022. 
https://www.epa.gov/system/files/documents/2023-05/cumulative%20impacts%20research-final%20report-epa%20600-r-22-014a%20%2812%29.pdf.
35. U.S. EPA. EJSCREEN: Environmental Justice Screening and Mapping 
Tool. https://www.epa.gov/ejscreen.
36. U.S. EPA. EnviroAtlas. https://www.epa.gov/enviroatlas.
37. U.S. EPA. Guidelines for Carcinogen Risk Assessment. EPA/630/P-
03/001F. Risk Assessment Forum. Washington, DC. March 2005. https://www.regulations.gov/document/EPA-HQ-OA-2007-0679-0001.
38. U.S. EPA. Supplemental Guidance for Assessing Susceptibility 
from Early-Life Exposure to Carcinogens. EPA/630/R-03/003F. Risk 
Assessment Forum. Washington, DC. March 2005. https://www.epa.gov/sites/default/files/2013-09/documents/childrens_supplement_final.pdf.
39. U.S. EPA. Peer Review Handbook (4th Edition). EPA/100/B-15/001. 
Science and Technology Policy Council. Washington, DC. October 2015. 
https://www.epa.gov/sites/default/files/2020-08/documents/epa_peer_review_handbook_4th_edition.pdf.
40. OMB. Final Information Quality Bulletin for Peer Review. Federal 
Register. (70 FR 2664, January 14, 2005). https://www.govinfo.gov/content/pkg/FR-2005-01-14/pdf/05-769.pdf.
41. U.S. EPA. Draft Risk Evaluation for C.I. Pigment Violet 29 
(Anthra[2,1,9-def:6,5,10-d'e'f']diisoquinoline 1,3,8,10(2H,9H)-
tetrone) CASRN: 81-33-4. 740R18015. Office of Chemical Safety and 
Pollution Prevention. Washington, DC. November 2018. https://www.regulations.gov/document/EPA-HQ-OPPT-2018-0604-0007.
42. U.S. EPA. Draft Supplemental Analysis to the Draft Risk 
Evaluation for 1,4-Dioxane. EPA-740-R1-8007. Office of Chemical 
Safety and Pollution Prevention. November 2020. https://www.regulations.gov/document/EPA-HQ-OPPT-2019-0238-0067.
43. TSCA Science Advisory Committee on Chemicals. Peer Review for 
EPA Draft Risk Evaluation for 1,4-Dioxane and Cyclic Aliphatic 
Bromide Cluster (HBCD). Meeting Minutes and Final Report No. 2019-
02. October 2019. https://www.regulations.gov/document/EPA-HQ-OPPT-2019-0238-0063.
44. Comments submitted to EPA in response to Notice of Availability 
on U.S. EPA. Procedures for Chemical Risk Evaluation Under the 
Amended Toxic Substances; Proposed Rule. https://

[[Page 74318]]

www.regulations.gov/docket/EPA-HQ-OPPT-2016-0654/comments.
45. Safe Drinking Water Act. 42 U.S.C. 300f et seq.
46. U.S. EPA. Guidelines for Ensuring and Maximizing the Quality, 
Objectivity, Utility, and Integrity, of Information Disseminated by 
the Environmental Protection Agency. EPA/260R-02-008. Office of 
Environmental Information. Washington, DC. October 2002. https://www.epa.gov/sites/default/files/2020-02/documents/epa-info-quality-guidelines_pdf_version.pdf.
47. U.S. EPA. Application of Systematic Review in TSCA Risk 
Evaluations. EPA/740/P1/8001. Office of Chemical Safety and 
Pollution Prevention. May 2018. https://www.epa.gov/sites/default/files/2018-06/documents/final_application_of_sr_in_tsca_05-31-18.pdf.
48. National Academies of Sciences Engineering and Medicine. The Use 
of Systematic Review in EPA's Toxic Substances Control Act Risk 
Evaluations. The National Academies Press. Washington, DC. 2021. 
https://doi.org/10.17226/25952.
49. U.S. EPA. (2021) Draft TSCA Systematic Review Protocol 
Supporting TSCA Risk Evaluations for Chemical Substances: A Generic 
TSCA Systematic Review Protocol with Chemical-Specific Methodologies 
(Version 1.0). EPA-D-20-031. Office of Chemical Safety and Pollution 
Prevention. Washington, DC. December 2021. https://www.regulations.gov/document/EPA-HQ-OPPT-2021-0414-0005.
50. NRC. Review of EPA's Integrated Risk Information System (IRIS) 
Process. The National Academies Press. Washington, DC. 2014. https://www.nap.edu/catalog/18764/review-of-epas-integrated-riskinformation-system-iris-process.
51. EDSTAC. Endocrine Disruptor Screening and Testing Advisory 
Committee, Final Report, Volume I-II. Washington, DC 1998. https://www.epa.gov/scipoly/oscpendo/pubs/edspoverview/finalrpt.htm.
52. U.S. EPA. Weight of Evidence in Ecological Assessment. EPA/100/
R-16/001. Risk Assessment Forum. Washington, DC. December 2016. 
https://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=P100SFXR.txt.
53. U.S. EPA. Endocrine Disruptor Screening Program (EDSP); Weight-
of-Evidence: Evaluating Results of EDSP Tier 1 Screening to Identify 
the Need for Tier 2 Testing. Office of Chemical Safety and Pollution 
Prevention. Washington, DC. 2011. https://www.regulations.gov/document/EPA-HQ-OPPT-2010-0877-0021.
54. U.S. EPA. ORD Staff Handbook for Developing IRIS Assessments 
(2022). EPA/600/R-22/268. Office of Research and Development. 
Washington, DC. https://cfpub.epa.gov/ncea/iris_drafts/recordisplay.cfm?deid=356370.
55. U.S. EPA. Tiered Data Reporting to Inform, Prioritization, Risk 
Evaluation, and Risk Management under TSCA. Office of Chemical 
Safety and Pollution Prevention. https://www.epa.gov/chemical-data-reporting/tiered-data-reporting-inform-prioritization-risk-evaluation-and-risk. (Accessed May 31, 2023.)

VI. Statutory and Executive Order Reviews

    Additional information about these statutes and Executive orders 
can be found at https://www.epa.gov/laws-regulations/laws-and-executive-orders.

A. Executive Orders 12866: Regulatory Planning and Review and 14094: 
Modernizing Regulatory Review

    This action is a ``significant regulatory action'' as defined in 
Executive Order 12866 (58 FR 51735, October 4, 1993), as amended by 
Executive Order 14094 (88 FR 21879, April 11, 2023). Accordingly, EPA 
submitted this action to the OMB for Executive Order 12866 review. 
Documentation of any changes made in response to the Executive Order 
12866 review are documented in the docket. EPA prepared an analysis of 
the potential costs associated with this action. This analysis can be 
found in Unit VI.B.

B. Paperwork Reduction Act (PRA)

    The information collection activities in this proposed rule have 
been submitted for approval to OMB under the PRA, 44 U.S.C. 3501 et 
seq. EPA has prepared a new rule-related Information Collection Request 
(ICR) document entitled ``Procedures for Requesting a Chemical Risk 
Evaluation under TSCA (Proposed Rule)'' and is identified by EPA ICR 
No. 2781.01, to replace an existing approved ICR. You can find a copy 
of the new ICR document (Ref. 4) in the docket for this rulemaking, and 
it is briefly summarized here.
    The information activities related to the current requirements for 
manufacturer-requested risk evaluations are already approved by OMB in 
an ICR entitled, ``Procedures for Requesting a Chemical Risk Evaluation 
under TSCA'' (EPA ICR No. 2559.03 and OMB Control No. 2070-0202) (Ref 
4). The proposed rule replacement ICR addresses the information 
collection requirements contained in the current regulations as well as 
in the amendments identified in this proposed rule. As addressed in the 
currently approved ICR and pursuant 40 CFR part 702, subpart B, the 
information collection activities are those carried out by a chemical 
manufacturer in requesting a specific chemical risk evaluation under 
TSCA be conducted by EPA. EPA established the process for conducting 
risk evaluations under TSCA. Chemicals that will undergo this 
evaluation include chemicals designated by the Agency as high-priority 
in accordance with 40 CFR part 702, subpart A, as well as chemicals for 
which EPA has granted requests made by manufacturers to have the 
chemicals evaluated under EPA's risk evaluation process. The 
replacement ICR addresses proposed amendments to information 
requirements for manufacturer-requested risk evaluations, including 
proposed amendments to information requirements addressing joint 
submissions, the scope of the requested risk evaluation, and the 
information to be provided in support of the requested risk evaluation, 
and fee payment. Please see Unit III.K. for additional information 
about these proposed amendments.
    The replacement ICR addresses adjustments to the estimated number 
of respondents, time for activities, and wage rates related to the 
current regulatory requirements as approved under OMB Control No. 2070-
0202. In addition, the replacement ICR addresses program changes 
related to the proposed amendments, including changes to content 
requirements for manufacturer-requested risk evaluation request and 
associated process changes. The estimated annual burden approved by OMB 
under OMB Control No. 2070-0202 is 419 hours. The total estimated 
annual respondent burden being proposed in the replacement ICR is 166 
hours, a net decrease of 253 hours. The primary driver in the burden 
decrease is the estimated number of responses dropping to 1 per year 
based on the number of requests EPA has received to date. Certain 
information included with a manufacturer-requested risk evaluation may 
be claimed as TSCA CBI in accordance with TSCA section 14 (15 U.S.C. 
2613), and any such claims must be substantiated in accordance with the 
Act.
    Respondents/affected entities: Persons that manufacture chemical 
substances and request a chemical be considered for risk evaluation by 
EPA. Such persons may voluntarily request a risk evaluation but would 
be required to comply with the requirements for such a request. See 
Unit I.A.
    Respondent's obligation to respond: Voluntary (15 U.S.C. 
2605(b)(4)).
    Estimated number of respondents: 3.
    Frequency of response: On occasion.
    Total estimated burden: 166 hours (per year). Burden is defined at 
5 CFR 1320.3(b).
    Total estimated cost: $115,711 (per year), includes $0 annualized 
capital or operation and maintenance 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

[[Page 74319]]

control number. The OMB control numbers for the EPA's regulations in 40 
CFR are listed in 40 CFR part 9.
    Submit your comments on the Agency's need for this information, the 
accuracy of the provided burden estimates and any suggested methods for 
minimizing respondent burden to EPA using the docket identified at the 
beginning of this rulemaking. EPA will respond to any ICR-related 
comments in the final rule. You may also send your ICR-related comments 
to OMB's Office of Information and Regulatory Affairs using the 
interface at https://www.reginfo.gov/public/do/PRAMain. Find this 
particular ICR by selecting ``Currently under Review--Open for Public 
Comments'' or by using the search function. OMB must receive comments 
no later than November 29, 2023.

C. Regulatory Flexibility Act (RFA)

    I certify that this action will not have a significant economic 
impact on a substantial number of small entities under the RFA, 5 
U.S.C. 601 et seq. The small entities subject to the requirements of 
this action are manufacturers of chemical substances that submit 
requests to EPA seeking chemical risk evaluations. The Agency has 
determined that a low number of small entities may be impacted by 
voluntarily submitting a request to EPA for a chemical to undergo a 
risk evaluation. The 2017 final rule considered firms in 60 different 
NAICS codes that may choose to pursue a manufacturer-requested risk 
evaluation (approximately 30,000 firms) of which 76 percent were 
classified as small business (approximately 22,000 firms). When EPA 
promulgated the 2017 final rule, the Agency estimated that it would 
receive 5 MRRE submissions per year. However, manufacturers have 
submitted only 4 MRRE requests since 2017 (or less than one request per 
year, on average). Therefore, based on the number of submissions 
received by EPA since 2017, the Agency estimates it will receive only 
one manufacture-requested risk revaluation per year. That is, only one 
out of approximately 22,000 small businesses is expected to choose to 
incur the submission costs ($115,711) in any one year and, thus, a 
significant number of small businesses would not be impacted by this 
rulemaking. The decision to request a risk evaluation for a chemical is 
voluntary and manufacturers may decide not to make such a request. 
Details of this analysis are presented in the rule-related ICR.

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. The costs involved in this action are 
imposed only on the private sector entities (manufacturers) that may 
voluntarily elect to submit a request for a risk evaluation as they 
would be required to comply with the proposed requirements for such 
requests.

E. Executive Order 13132: Federalism

    This action does not have federalism implications as specified in 
Executive Order 13132 (64 FR 43255, August 10, 1999) because 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.
    TSCA section 18(c)(3) defines the scope of Federal preemption with 
respect to any final rule EPA issues under TSCA section 6(a). That 
provision provides that Federal preemption of ``statutes, criminal 
penalties, and administrative actions'' applies to ``the hazards, 
exposures, risks, and uses or conditions of use of such chemical 
substances included in any final action the Administrator takes 
pursuant to [TSCA section 6(a)].'' EPA reads this to mean that states 
are preempted from imposing requirements through statutes, criminal 
penalties, and administrative actions relating to any ``hazards, 
exposures, risks, and uses or conditions of use'' evaluated in the 
final risk evaluation and informing the risk determination that EPA 
addresses in the TSCA section 6(a) rulemaking. For example, Federal 
preemption applies even if EPA does not regulate in that final rule a 
particular COU, but that COU was evaluated in the final risk 
evaluation.

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) because 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

    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. Therefore, 
this action is not subject to Executive Order 13045 because it does not 
concern an environmental health risk or safety risk. Since this action 
does not concern human health risks, EPA's Policy on Children's Health 
also does not apply. This procedural rule would address how EPA 
evaluates the risks of existing chemicals under TSCA, including 
potential risks to children and other PESS. EPA must initiate a 
rulemaking to address the unreasonable risk to human health or the 
environment that the Agency may determine are presented by a chemical 
substance as set forth in a TSCA risk evaluation. Although this 
procedural rule itself would not directly affect the level of 
protection provided to human health or the environment, EPA expects 
that this rulemaking would improve the Agency's consideration of risks 
to children and other PESS and, in turn, better inform the Agency's 
determination of whether a chemical substance presents an unreasonable 
risk of injury to health under its conditions of use. An EPA rulemaking 
to address an unreasonable risk of injury to health that the 
Administrator determines is presented by a chemical substance following 
a risk evaluation could qualify as a covered regulatory action under 
E.O. 13045 and could be subject to EPA's Policy on Children's Health.

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

    This action is not a ``significant energy action'' under 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 and has not otherwise been designated by the Administrator of 
OMB's Office of Information and Regulatory Affairs as a ``significant 
energy action.''

[[Page 74320]]

I. National Technology Transfer and Advancement Act (NTTAA)

    This proposed rulemaking does not involve technical standards. As 
such, NTTAA section 12(d), 15 U.S.C. 272 note, does not apply to this 
action.

J. Executive Order 12898: Federal Actions To Address Environmental 
Justice in Minority Populations and Low-Income Populations and 
Executive Order 14096: Revitalizing Our Nation's Commitment to 
Environmental Justice for All

    EPA believes that it is not practicable to assess whether the human 
health or environmental conditions that exist prior to this action 
result in disproportionate and adverse effects on communities with 
environmental justice concerns consistent with Executive Order 14096 
(88 FR 25251, April 26, 2023) and Executive Order 12898 (59 FR 7629, 
February 16, 1994). This action proposes revisions to the procedures 
that EPA will use to evaluate the risk of existing chemical substances 
pursuant to TSCA, and the Agency cannot foresee the final results of 
those evaluations. However, by specifically including overburdened 
communities in the regulatory definition of PESS, the Agency believes 
that this action would assist EPA and others in determining the 
potential exposures, hazards and risks to overburdened communities 
associated with existing chemicals a part of a TSCA risk evaluation. 
The proposed inclusion of overburdened communities among the PESS 
considered in a chemical risk evaluation would also enable the Agency 
to design appropriate risk management approaches to address the 
unreasonable risk that the Agency may determine is presented by a 
chemical, including any unreasonable risk that is disproportionately 
borne by communities with environmental justice concerns.
    The information supporting this Executive order review is presented 
in Unit III.G.4.

List of Subjects in 40 CFR Part 702

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

    Dated: October 18, 2023.
Michal Freedhoff,
Assistant Administrator, Office of Chemical Safety and Pollution 
Prevention.

    Therefore, for the reasons stated in the preamble, EPA proposes to 
amend 40 CFR part 702 as follows:

PART 702--GENERAL PRACTICES AND PROCEDURES

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

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

0
2. Revise and republish subpart B to read as follows:
Subpart B--Procedures for Chemical Substance Risk Evaluations
Sec.
702.31 General provisions.
702.33 Definitions.
702.35 Chemical substances subject to risk evaluation.
702.37 Evaluation requirements.
702.39 Components of risk evaluation.
702.41 Peer review.
702.43 Risk evaluation actions and timeframes.
702.45 Submission of manufacturer requests for risk evaluations.
702.47 Interagency collaboration.
702.49 Publicly available information.

Subpart B--Procedures for Chemical Substance Risk Evaluations


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)) beginning [30 DAYS AFTER DATE OF PUBLICATION 
OF THE FINAL RULE IN THE FEDERAL REGISTER]. For risk evaluations 
initiated prior to this date, but not yet finalized, EPA will seek to 
apply the requirements in this subpart to the extent practicable. These 
requirements shall not apply retroactively to risk evaluations already 
finalized.
    (d) Categories of chemical substances. Consistent with EPA's 
authority to take action with respect to categories of chemicals under 
15 U.S.C. 2625(c), all references in this part to ``chemical'' or 
``chemical substance'' shall also apply to ``a category of chemical 
substances.''


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 from a chemical 
substance across multiple routes and across multiple pathways.
    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 physical course a chemical substance takes from 
the source to the organism exposed.
    Potentially exposed or susceptible subpopulation means a group of 
individuals within the general population identified by 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, the elderly, or overburdened communities.
    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 ways a chemical substance enters an organism after 
contact, e.g., by ingestion, inhalation, or dermal absorption.
    Sentinel exposure means the exposure from a 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.


Sec.  702.35  Chemical substances subject to risk evaluation.

    (a) Chemical substances undergoing risk evaluation. A risk 
evaluation for a chemical substance designated by EPA as a High-
Priority Substance pursuant to

[[Page 74321]]

the prioritization process described in subpart A or initiated at the 
request of a manufacturer or manufacturers under Sec.  702.45, will be 
conducted in accordance with this part, subject to Sec.  702.31(c).
    (b) Percentage requirements. EPA 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 Sec.  702.37, and not more than 
50%.
    (c) Manufacturer-requested risk evaluations 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 EPA. Such evaluations are not 
subject to the percentage requirements in paragraph (b) of this 
section.


Sec.  702.37  Evaluation requirements.

    (a) Considerations. (1) EPA will use applicable EPA guidance when 
conducting risk evaluations, as appropriate and where it represents the 
best available science.
    (2) EPA will document that the risk evaluation is consistent with 
the best available science and based on the weight of the scientific 
evidence. Considerations for determining best available science shall 
include, but are not limited to, the following as applicable:
    (i) 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;
    (ii) The extent to which the information is relevant for the 
Administrator's use in making a decision about a chemical substance or 
mixture;
    (iii) The degree of clarity and completeness with which the data, 
assumptions, methods, quality assurance, and analyses employed to 
generate the information are documented;
    (iv) 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
    (v) The extent of independent verification or peer review of the 
information or of the procedures, measures, methods, protocols, 
methodologies or models.
    (3) EPA will ensure that all supporting analyses and components of 
the risk evaluation are suitable for their intended purpose, and 
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 conditions of use, based on the weight of the 
scientific evidence.
    (4) EPA will not exclude conditions of use from the scope of the 
risk evaluation, but a fit-for-purpose approach may result in varying 
types and levels of analysis and supporting information for certain 
conditions of use, consistent with paragraph (b) of this section. 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.
    (5) EPA will determine whether a chemical substance does or does 
not present an unreasonable risk after considering the risks posed 
under all of the conditions of use and, where EPA makes a determination 
of unreasonable risk, EPA intends to identify the conditions of use 
that significantly contribute to such determination.
    (6) 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 will apply systematic review and/or systematic approaches 
to reviewing reasonably available information that are objective, 
unbiased, and transparent.
    (3) EPA may determine that certain information gaps can be 
addressed through application of assumptions, uncertainty factors, 
models, and/or screening to conduct its analysis with respect to the 
chemical substance, consistent with 15 U.S.C. 2625. The approaches used 
will be determined by the quality of reasonably available 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.
    (4) 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 also use such authorities during the performance of a risk 
evaluation to obtain information as needed and on a case-by-case basis 
to ensure that EPA has adequate, reasonably available information to 
perform the evaluation. 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.
    (5) Among other sources of information, EPA will also consider 
information and advice provided by the Science Advisory Committee on 
Chemicals established pursuant to 15 U.S.C. 2625(o).


Sec.  702.39  Components of risk evaluation.

    (a) In general. Each risk evaluation will include all of the 
following components:
    (1) A Scope;
    (2) A Hazard Assessment;
    (3) An Exposure Assessment;
    (4) A Risk Characterization; and
    (5) A Risk Determination.
    (b) Scope of the risk evaluation. The scope of the risk evaluation 
will include all the following:
    (1) The condition(s) of use the EPA expects 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 EPA under the conditions of use that EPA plans to 
evaluate.
    (3) The ecological receptors that EPA plans to evaluate.
    (4) The hazards to health and the environment that EPA plans to 
evaluate.
    (5) A description of the reasonably available information and 
scientific approaches EPA plans to use in the risk evaluation.
    (6) A conceptual model that describes the actual or predicted 
relationships between the chemical substance, its associated conditions 
of use through predicted exposure scenarios, and the identified human 
and environmental receptors and human and ecological health hazards.
    (7) An analysis plan that includes hypotheses and descriptions 
about the relationships identified in the conceptual model and the 
approaches and strategies EPA intends to use to assess exposure and 
hazard effects, and to characterize risk; and a description, including 
quality, of the data, information, methods, and models, that EPA 
intends to use in the analysis and how uncertainty and variability will 
be characterized.

[[Page 74322]]

    (8) EPA's plan for peer review consistent with Sec.  702.41.
    (c) Hazard assessment. (1) The hazard assessment process includes 
the identification, evaluation, and synthesis of information to 
describe the potential health and environmental hazards of the chemical 
substance under the conditions of use.
    (2) Hazard information related to potential health and 
environmental hazards of the chemical substance will be reviewed in a 
manner consistent with best available science based on the weight of 
scientific evidence and all assessment methods will be documented.
    (3) Consistent with Sec.  702.37(b), information evaluated may 
include, but would not be limited to: Human epidemiological studies, in 
vivo and/or in vitro laboratory studies, biomonitoring and/or human 
clinical studies, ecological field data, read across, mechanistic and/
or kinetic studies in a variety of test systems. These may include but 
are not limited to: toxicokinetics and toxicodynamics (e.g., 
physiological-based pharmacokinetic modeling), and computational 
toxicology (e.g., high-throughput assays, genomic response assays, data 
from structure-activity relationships, in silico approaches, and other 
health effects modeling).
    (4) The hazard information relevant to the chemical substance will 
be evaluated for identified human and environmental receptors, 
including all identified potentially exposed or susceptible 
subpopulation(s) determined to be relevant, for the exposure scenarios 
relating to the conditions of use.
    (5) The relationship between the dose of the chemical substance and 
the occurrence of health and environmental effects or outcomes will be 
evaluated.
    (6) Hazard identification will include an evaluation of the 
strengths, limitations, and uncertainties associated with the 
reasonably available information.
    (d) Exposure assessment. (1) Where relevant, the likely duration, 
intensity, frequency, and number of exposures under the conditions of 
use will be considered.
    (2) Exposure information related to potential human health or 
ecological hazards of the chemical substance will be reviewed in a 
manner consistent with best available science based on the weight of 
scientific evidence and all assessment methods will be documented.
    (3) Consistent with Sec.  702.37(b), information evaluated may 
include, but would not be limited to: chemical release reports, release 
or emission scenarios, data and information collected from monitoring 
or reporting, release estimation approaches and assumptions, biological 
monitoring data, workplace monitoring data, chemical exposure health 
data, and exposure modeling.
    (4) Chemical-specific factors, including, but not limited to 
physical-chemical properties and environmental fate and transport 
parameters, will be examined.
    (5) The human health exposure assessment will consider all 
potentially exposed or susceptible subpopulation(s) determined to be 
relevant.
    (6) Environmental health exposure assessment will characterize and 
evaluate the interaction of the chemical substance with the ecological 
receptors and the exposures considered, including populations and 
communities, depending on the chemical substance and the ecological 
characteristic involved.
    (7) EPA will describe whether sentinel exposures under the 
conditions of use were considered and the basis for their 
consideration.
    (8) EPA will consider aggregate exposures to the chemical 
substance, and, when supported by reasonably available information, 
consistent with the best available science and based on the weight of 
scientific evidence, include an aggregate exposure assessment in the 
risk evaluation, or will otherwise explain in the risk evaluation the 
basis for not including such an assessment.
    (9) EPA will assess all exposure routes and pathways relevant to 
the chemical substance under the conditions of use, including those 
that are regulated under other Federal statutes.
    (e) Risk characterization--(1) Requirements. To characterize the 
risks from the chemical substance, EPA will:
    (i) Integrate the hazard and exposure assessments into quantitative 
and/or qualitative estimates relevant to specific risks of injury to 
health or the environment, including any potentially exposed or 
susceptible subpopulations identified, under the conditions of use.
    (ii) Not consider costs or other non-risk factors;
    (iii) Describe the weight of the scientific evidence for the 
identified hazards and exposures.
    (2) Summary of considerations. EPA 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:
    (i) 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 and approaches used in the 
assessment.
    (ii) 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.
    (iii) 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.
    (iv) Additional considerations for environmental risk. For 
evaluation of environmental risk, 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.
    (f) Risk determination. (1) As part of the risk evaluation, EPA 
will make a single determination as to whether the 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.
    (2) In determining whether unreasonable risk is presented, EPA's 
consideration of occupational exposure scenarios will take into account 
reasonably available information, including known and reasonably 
foreseen circumstances where subpopulations of workers are exposed due 
to the absence or ineffective use of personal protective equipment. EPA 
will not consider exposure reduction

[[Page 74323]]

based on assumed use of personal protective equipment as part of the 
risk determination.


Sec.  702.41  Peer review.

    EPA expects that peer review activities on risk evaluations 
conducted pursuant to 15 U.S.C. 2605(b)(4)(A), or portions thereof, 
will be consistent with the applicable peer review policies, 
procedures, guidance documents, and methods pursuant to guidance 
promulgated by Office of Management and Budget, EPA, and in accordance 
with 15 U.S.C. 2625(h) and (i).


Sec.  702.43  Risk evaluation actions and timeframes.

    (a) Draft scope. (1) For each risk evaluation to be conducted EPA 
will publish a document-that specifies the draft scope of the risk 
evaluation EPA plans to conduct and publish a notice of availability in 
the Federal Register. The document will address the elements in Sec.  
702.39(b).
    (2) EPA generally expects to publish the draft scope during the 
prioritization process concurrent with publication of a proposed 
designation as a High-Priority Substance pursuant to Sec.  702.9(g), 
but no later than 3 months after the initiation of the risk evaluation 
process for the chemical substance.
    (3) 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 scope. EPA will open a docket to facilitate receipt of 
public comments.
    (b) Final scope. (1) EPA will, no later than 6 months after the 
initiation of a risk evaluation, publish a document that specifies the 
final scope of the risk evaluation EPA plans to conduct, and publish a 
notice of availability in the Federal Register. The document shall 
address the elements in Sec.  702.39(b).
    (2) 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.
    (c) Draft risk evaluation. EPA will publish a draft risk 
evaluation, publish a notice of availability in the Federal Register, 
open a docket to facilitate receipt of public comment, and provide no 
less than a 60-day comment period, during which time the public may 
submit comment on EPA's draft risk evaluation. The document shall 
include the elements in Sec.  702.39(c) through (f).
    (d) Final risk evaluation. (1) EPA will complete and publish a 
final risk evaluation for the chemical substance under the conditions 
of use as soon as practicable, but not later than 3 years after the 
date on which EPA initiates the risk evaluation. The document shall 
include the elements in Sec.  702.39(c) through (f) and EPA will 
publish a notice of availability in the Federal Register.
    (2) EPA 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.
    (e) Final determination of unreasonable risk. Upon determination by 
the EPA pursuant to Sec.  702.39(f) that a chemical substance presents 
an unreasonable risk of injury to health or the environment, EPA will 
initiate action as required pursuant to 15 U.S.C. 2605(a).
    (f) Final determination of no unreasonable risk. A determination by 
the EPA pursuant to Sec.  702.39(f) that the chemical substance 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.
    (g) Substantive revisions to scope documents and risk evaluations. 
The circumstances under which EPA will undertake substantive revisions 
to scope and risk evaluation documents are as follows:
    (1) Draft documents. To the extent there are changes to a draft 
scope or draft risk evaluation, EPA will describe such changes in the 
final document.
    (2) Final scope. To the extent there are changes to the scope of 
the risk evaluation after publication of the final scope document, EPA 
will describe such changes in the draft risk evaluation, or, where 
appropriate and prior to the issuance of a draft risk evaluation, may 
make relevant information publicly available in the docket and publish 
a notice of availability of that information in the Federal Register.
    (3) Final risk evaluation. For any chemical substance for which EPA 
has already finalized a risk evaluation, EPA will generally not revise, 
supplement, or reissue a final risk evaluation without first undergoing 
the procedures at Sec.  702.7 to re-initiate the prioritization process 
for that chemical substance, except where EPA has determined it to be 
in the interest of protecting human health and the environment to do 
so, considering the statutory responsibilities and deadlines under 15 
U.S.C. 2605.
    (4) Process for revisions to final risk evaluations. Where EPA 
determines to revise or supplement a final risk evaluation pursuant to 
paragraph (g)(3) of this section, EPA will follow the same procedures 
in this section including publication of a new draft and final risk 
evaluation and solicitation of public comment in accordance with 
Sec. Sec.  702.43(c) and (d), and peer review, as appropriate, in 
accordance with Sec.  702.41.


Sec.  702.45  Submission of manufacturer requests for risk evaluations.

    (a) General provisions. (1) One or more manufacturers of a chemical 
substance may request that EPA conduct a risk evaluation on a chemical 
substance.
    (2) Such requests must comply with all the requirements, 
procedures, and criteria in this section.
    (3) Subject to limited exceptions in paragraph (e)(7)(iii) of this 
section, it is the burden of the requesting manufacturer to provide EPA 
with the information necessary to carry out the risk evaluation.
    (4) In determining whether there is sufficient information to 
support a manufacturer-requested risk evaluation, EPA expects to apply 
the same standard as it would for EPA-initiated risk evaluations, 
including but not limited to the considerations and requirements in 
Sec.  702.37.
    (5) EPA may identify data needs at any time during the process 
described in this section, and, by submitting a request for risk 
evaluation under this section, the requesting manufacturer agrees to 
provide, or develop and provide, EPA with information EPA deems 
necessary to carry out the risk evaluation, consistent with the 
provisions described in this subpart.
    (6) EPA will not expedite or otherwise provide special treatment to 
a manufacturer-requested risk evaluation pursuant to 15 U.S.C. 
2605(b)(4)(E)(ii).
    (7) Once initiated in accordance with paragraph (e)(9) of this 
section, EPA will conduct manufacturer-requested risk evaluations 
following the procedures in Sec. Sec.  702.37 through 702.43 and 
Sec. Sec.  702.47 through 702.49 of this subpart.
    (b) Method for submission. All manufacturer-requested risk 
evaluations under this subpart must be submitted via the EPA Central 
Data Exchange (CDX) found at https://cdx.epa.gov.
    (c) Content of request. 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.

[[Page 74324]]

    (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, Chemical 
Abstracts Service (CAS) number, and molecular structure of the chemical 
substance.
    (3) For requests pertaining to a category of chemical substances, 
an explanation of why the category is appropriate under 15 U.S.C. 
2625(c). EPA will determine whether the category is appropriate for 
risk evaluation as part of reviewing the request in paragraph (e) of 
this section.
    (4) A description of the circumstances under which the chemical 
substance is intended, known, or reasonably foreseen to be 
manufactured, processed, distributed in commerce, used, or disposed of, 
and all information known to or reasonably ascertainable by the 
requesting manufacturer that supports the identification of the 
circumstances described in this paragraph (c)(4).
    (5) All information known to or reasonably ascertainable by the 
requesting manufacturer on the health and environmental hazard(s) of 
the chemical substance, human and environmental exposure(s), and 
exposed population(s), including but not limited to:
    (i) The chemical substance's exposure potential, including 
occupational, general population and consumer exposures, and facility 
release information;
    (ii) The chemical substance's hazard potential, including all 
potential environmental and human health hazards;
    (iii) The chemical substance's physical and chemical properties.
    (iv) The chemical substance's fate and transport properties 
including persistence and bioaccumulation;
    (v) Potentially exposed or susceptible subpopulations which the 
manufacturer(s) believes to be relevant to the EPA risk evaluation;
    (vi) 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);
    (vii) The chemical substance's production volume or significant 
changes in production volume; and
    (viii) Any other information relevant to the hazards, exposures 
and/or risks of the chemical substance.
    (6) Where information described in paragraph (c)(4) or (5) of this 
section is unavailable, an explanation as to why, and the rationale for 
why, in the requester's view, the provided information is nonetheless 
sufficient to allow EPA to complete a risk evaluation on the chemical 
substance.
    (7) Copies of all information referenced in paragraph (c)(5) of 
this section, or citations if the information is readily available from 
public sources.
    (8) A signed certification that all information contained in the 
request is accurate and complete, as follows:

    I certify that to the best of my knowledge and belief:
    (A) The company named in this request manufactures the chemical 
substance identified for risk evaluation.
    (B) All information provided in the request is complete and 
accurate as of the date of the request.
    (C) I have either identified or am submitting all information in 
my possession and control, and a description of all other data known 
to or reasonably ascertainable by me as required 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.

    (9) Where appropriate, 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. Persons submitting a request 
under this subpart are subject to EPA confidentiality regulations at 40 
CFR part 2, subpart B, and 40 CFR part 703.
    (e) EPA process for reviewing requests. (1) Public notification of 
receipt of request. Within 15 days of receipt of a manufacturer-
requested risk evaluation, EPA will notify the public that such request 
has been received.
    (2) Initial review for completeness. EPA will determine whether the 
request appears to meet the requirements specified in this section 
(i.e., complete), or whether the request appears to not have met the 
requirements specified in this section (i.e., incomplete). EPA will 
notify the requesting manufacturer of the outcome of this initial 
review. For requests initially determined to be incomplete, EPA will 
cease review pending actions taken by the requesting manufacturer 
pursuant to paragraph (f) of this section. For requests initially 
determined to be complete, EPA will proceed to the public notice and 
comment process described in paragraph (e)(3) of this section.
    (3) Public notice and comment. No later than 90 days after 
initially determining a request to be complete pursuant to paragraph 
(e)(2) 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 60-day public comment period. The docket will 
contain the CBI sanitized copies of the request and all supporting 
information. The notice will encourage the public to submit comments 
and information relevant to the manufacturer-requested risk evaluation, 
including, but not limited to, identifying information not provided in 
the request, information the commenter believes necessary to conduct a 
risk evaluation, and any other information relevant to the conditions 
of use.
    (4) Secondary review for sufficiency. Within 90 days following the 
end of the comment period in paragraph (e)(3) of this section, EPA will 
further consider whether public comments highlight deficiencies in the 
request not identified during EPA's initial review, and/or that the 
available information is not sufficient to support a reasoned 
evaluation. EPA will notify the requesting manufacturer of the outcome 
of this review. For requests determined to not be supported by 
sufficient information, EPA will cease review pending actions taken 
pursuant to paragraph (f) of this section. For requests determined to 
be supported by sufficient information, EPA will proceed with request 
review process in accordance with paragraph (e)(5) of this section.
    (5) Grant. Where EPA determines a request to be complete and 
sufficiently supported in accordance with paragraphs (e)(2) and (4) of 
this section, and subject to the percentage limitations in TSCA section 
6(b)(4)(E)(i)(II), EPA will grant the request. A grant does not mean 
that EPA has all information necessary to complete the risk evaluation.
    (6) Publication of draft conditions of use and request for 
information. EPA will publish a notice in the Federal Register that 
identifies draft conditions of use, requests relevant information from 
the public, and provides no less than a 60-day public comment period. 
Within 90 days following the close of the public comment period in this 
paragraph, EPA will determine whether further information is needed to 
carry out the risk evaluation and notify the requesting manufacturer(s) 
of its determination, pursuant to paragraph (e)(7) of this section. If 
EPA determines at this time that no further information is necessary, 
EPA will initiate the risk evaluation, pursuant to paragraph (e)(9) of 
this section.
    (7) Identification of information needs. Where additional 
information

[[Page 74325]]

needs are identified, EPA will notify the requesting manufacturer(s) 
and set a reasonable amount of time, as determined by EPA, for 
response. In response to EPA's notice, and subject to the limitations 
in paragraph (g) of this section, the requesting manufacturer(s) may:
    (i) Provide the necessary information. EPA will set a reasonable 
amount of time, as determined by EPA, for the requesting 
manufacturer(s) to produce or develop and produce the information. Upon 
receipt of the new information, EPA will review for sufficiency and 
make publicly available to the extent possible, including CBI-sanitized 
copies of that information; or
    (ii) Withdraw the risk evaluation request. Fees to be collected or 
refunded shall be determined pursuant to paragraph (k) of this section 
and 40 CFR 700.45; or
    (iii) Request that EPA obtain the information using authorities 
under TSCA sections 4, 8 or 11. The requesting manufacturer(s) must 
provide a rationale as to why the information is not reasonably 
ascertainable to them. EPA will review and provide notice of its 
determination to the requesting manufacturer. Upon receipt of the 
information, EPA will review the additional information for sufficiency 
and provide additional public notice.
    (8) Unfulfilled information needs. In circumstances where there 
have been additional data needs identified pursuant to paragraph (e)(7) 
of this section but the requesting manufacturer(s) is unable or 
unwilling to fulfill those needs in a timely manner, has produced 
information that is insufficient as determined by EPA, or where EPA 
determines that a request to use TSCA authorities under section 4, 8 or 
11 is not warranted, EPA may deem the request to be constructively 
withdrawn under paragraph (e)(7)(ii) of this section.
    (9) Initiation of the risk evaluation. Within 90 days of the end of 
the comment period provided in paragraph (e)(6) of this section, or 
within 90 days of EPA determining that information pursuant to 
paragraph (e)(7) of this section is sufficient, EPA will initiate the 
requested risk evaluation and follow all requirements in this subpart, 
including but not limited to Sec. Sec.  702.37 through 702.43 and 
Sec. Sec.  702.47 through 702.49 of this subpart, and notify the 
requesting manufacturer and the public. Initiation of the risk 
evaluation does not limit or prohibit the Agency from identifying 
additional data needs during the risk evaluation process.
    (f) Incomplete or insufficient request. Where EPA has determined 
that a request is incomplete or insufficient pursuant to paragraph 
(e)(2) or (4) of this section, requesting manufacturer(s) may 
supplement and resubmit the request. EPA will follow the process 
described in paragraph (e) of this section as it would for a new 
request.
    (g) Withdrawal of request. Requesting manufacturer(s) may withdraw 
a request at any time prior to EPA's grant of such request pursuant to 
paragraph (e)(5) of this section, or in accordance with paragraph 
(e)(7) of this section and subject to payment of applicable fees. 
Requesting manufacturers may not withdraw a request once EPA has 
initiated the risk evaluation. EPA may deem a request constructively 
withdrawn in the event of unfulfilled information needs pursuant to 
paragraph (e)(8) of this section or non-payment of fees as required in 
40 CFR 700.45. EPA will notify the requesting manufacturer and the 
public of the withdrawn request.
    (h) Data needs identified post-initiation. Where EPA identifies 
additional data needs after the risk evaluation has been initiated, the 
requesting manufacturer(s) may remedy the deficiency pursuant to 
paragraph (e)(7)(i) or (iii) of this section.
    (i) Supplementation of original request. At any time prior to the 
end of the comment period described in paragraph (e)(6) of this 
section, the requesting manufacturer(s) may supplement the original 
request with any new information that becomes available to the 
manufacturer(s). At any point prior to the completion of a 
manufacturer-requested 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 reasonably ascertainable information that 
has the potential to change EPA's risk evaluation. Such information 
must be submitted consistent with 15 U.S.C. 2607(e) if the information 
is subject to that section or otherwise within 30 days of the 
manufacturer's obtaining the information.
    (j) Limitations on manufacturer-requested risk evaluations--
    (1) In general. EPA will initiate a risk evaluation for all 
requests from manufacturers 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%.
    (2) 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 give preference to requests for risk evaluations on chemical 
substances:
    (i) First, for which EPA 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.
    (k) Fees. Manufacturers must pay fees to support risk evaluations 
as specified under 15 U.S.C. 2605(b)(4)(E)(ii), and in accordance with 
15 U.S.C. 2525(b) and 40 CFR 700.45. In the event that a request for a 
risk evaluation is withdrawn by the requesting manufacturer pursuant to 
paragraph (g) of this section, the total fee amount due will be either, 
in accordance with 40 CFR 700.45(c)(2)(x) or (xi), 50% or 100% of the 
actual costs expended in carrying out the risk evaluation as of the 
date of receipt of the withdrawal notice. The payment amount will be 
determined by EPA, and invoice or refund issued to the requesting 
manufacturer(s) as appropriate.


Sec.  702.47  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.  702.49  Publicly available information.

    For each risk evaluation, EPA will maintain a public docket at 
https://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 EPA under 15 U.S.C. 
2603;
    (d) A nontechnical summary of the risk evaluation;

[[Page 74326]]

    (e) A list of the studies, with the results of the studies, 
considered in carrying out each risk evaluation;
    (f) Any 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. 2023-23428 Filed 10-27-23; 8:45 am]
BILLING CODE 6560-50-P


