U.S. Environmental Protection Agency

Trichloroethylene (TCE); Revision to Toxic Substances Control Act

(TSCA) Risk Determination

EPA-HQ-OPPT-2016-0737

Response to Public Comments

December 2022


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Trichloroethylene (TCE); Revision to Toxic Substances Control Act (TSCA) Risk Determination

Response to Public Comments Received

Table of Contents

Acronyms and Abbreviations	iii

Introduction	iv

Table 1: Index of Comment Submissions Sorted by Submission Number	v

Section 1 - General support for the draft revision to the risk determination	1

Section 2 - General opposition to the draft revision to the unreasonable risk determination	1

Section 3 - Legal issues	2

Section 3.1 - Statutory authority and TSCA section 26	2

Section 3.2 - Process of revising the risk determination	5

Section 4 - Revisions to the risk determination	6

Section 4.1 - Whole chemical approach vs. individual condition of use (COU)	6

Section 4.1.1 - Support for the whole chemical approach	6

Section 4.1.2 - Opposition to the whole chemical approach	8

Section 4.1.3 - Inconsistency with TSCA and Risk Evaluation Rule	10

Section 4.1.4 - Other comments on the whole chemical approach	17

Section 4.2 - Baseline scenario that does not assumes PPE or other mitigation measures in
place	18

Section 4.2.1 - Support for EPA's intention not to assume PPE or other mitigation measures
are in place	18

Section 4.2.2 - Opposition to EPA's intention not to assume PPE or other mitigation
measures are in place	20

Section 4.2.3 - OSHA requirements and industry best practices	26

Section 4.2.4 - Other comments regarding determination of unreasonable risk not assuming
PPE or other mitigations measures are in place	27

Section 4.2.5 - Permissible exposure limits (PELs)	30

Section 4.2.6 - Other comments on OSHA requirements or best practices	31

Section 5 - Unreasonable risk determination	32

Section 6 - Conditions of use that drive the unreasonable risk determination	35

Section 6.1 - Processing	35

Section 6.2 - Industrial and commercial use	35

Section 7 - Comments regarding conditions of use that do not drive the unreasonable risk
determination	36

Section 8 - Comments regarding EPA's withdrawal of the associated orders	38

Section 9 - Comments on EPA's screening approach to assess risks from air and water pathways
	39

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Trichloroethylene (TCE); Revision to Toxic Substances Control Act (TSCA) Risk Determination

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Section 10 - Other comments related to the draft revision of the risk determination	40

Previously submitted comments	40

Risk Management	40

Other	41

Section 11 - Comments on potential revisions to other risk determinations for the first ten
chemicals	43

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Acronyms and Abbreviations

APF

Assigned protection factor

COU

Condition of use

ECEL

Existing Chemical Exposure Limit

EPA

U.S. Environmental Protection Agency

HBCD

Cyclic aliphatic bromide cluster

NASEM

National Academies of Science, Engineering, and Medicine

NIOSH

U.S. National Institute for Occupational Safety and Health

ONU

Occupational non-user

OSHA

U.S. Occupational Safety and Health Administration

OSH Act

Occupational Safety and Health Act of 1970

PEL

Permissible exposure limit

PESS

Potentially exposed or susceptible subpopulation

PF

Protection factor

PPE

Personal protective equipment

PV29

Colour Index Pigment Violet 29

SACC

Science Advisory Committee on Chemicals

TCE

T richloroethylene

TSCA

Toxic Substances Control Act

U.S.

United States

u.s.c.

United States Code

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Trichloroethylene (TCE); Revision to Toxic Substances Control Act (TSCA) Risk Determination

Response to Public Comments Received

Introduction

On July 7, 2022, the U.S. Environmental Protection Agency (EPA) published a notice of
availability and request for comment on a draft revision to the Toxic Substances Control Act
(TSCA) Risk Determination for Trichloroethylene (TCE). In the notice, EPA announced that
public comments would be accepted until August 8, 2022.

EPA received a total of 15 public comments and determined that all comments are unique and
responsive to the request for comments. Table 1, Index of Comment Submissions Sorted by
Submission Number, identifies the commenter name and the comment number for the 15 unique
submissions included in this summary.

The comment summaries and responses that follow are organized into issue topic areas, as
indicated in the table of contents.

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Trichloroethylene (TCE); Revision to Toxic Substances Control Act (TSCA) Risk Determination

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Table 1: Index of Comment Submissions Sorted by Submission Number

Submission Number

Orgiiniziilion Name



Household & Commercial Products Association

EPA-HI

American Chemistry Council

EPA-HI

Alliance for Responsible Atmospheric Policy

EPA-HI

Environmental Defense Fund

EPA-HI r-20



136

U.S. Chamber of Commerce

EPA-HI





National Association of Chemical Distributors

EPA-HI



138

Halogenated Solvents Industry Alliance, Inc.

EPA-HI





Halogenated Solvents Industry Alliance, Inc.

EPA-HI



140

American Chemistry Council

EPA-HI r-20





American Federation of Labor and Congress of Industrial
Organizations

EPA-HI



142

Chemical Users Coalition

EPA-HI





Viant Collegeville, LLC

EPA-HIMIPPH .01 0 '> 01 1 1

Safer Chemicals Healthy Families, Earthjustice and
Natural Resources Defense Council

EPA-HI

Alliance for Automotive Innovation

EPA-HI

Hazardous Waste Management Program in King County,
WA

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Trichloroethylene (TCE); Revision to Toxic Substances Control Act (TSCA) Risk Determination

Response to Public Comments Received

Section 1 - General support for the draft revision to the risk determination

Comments that provided general support also provided more substantive comments that are
summarized in other portions of the summary report.

Several non-governmental environmental and health advocacy organizations (0135, 0144)
provided general support for the revised TCE unreasonable risk determination. The organizations
explained that they favored the change to a whole chemical approach because, among other
things, the whole chemical approach better aligns with the goals of TSCA and the 2016
Lautenberg amendments. The organizations stated that by removing the assumptions that
workers are always provided and always properly wear personal protective equipment (PPE),
EPA can adopt risk management that better protect not only workers but also other potentially
exposed or susceptible subpopulations (PESSs). Similarly, a comment submitted by several state
and local government agencies and organizations (0146) expressed strong support for EPA's new
path forward for TSCA risk evaluations. The commenter encouraged EPA to apply a whole-of-
government approach to chemical regulation, as it has begun to do with lead and polyfluoroalkyl
substances and continue to withdraw past determinations of no unreasonable risk for specific
conditions of use in the first ten risk evaluations.

EPA RESPONSE:

EPA appreciates the support for the revised unreasonable risk determination.

Section 2 - General opposition to the draft revision to the unreasonable risk determination

The comment that provided general opposition also provided more substantive comments that
are summarized in other portions of the summary report.

An industry trade organization (0145) stated that the revisions to the risk determination will
change public interpretations of risk, have unwarranted impacts on future risk management
decision-making and cause unintended regulatory impacts on articles (including replacement
parts) containing certain substances.

EPA RESPONSE:

EPA would like to reiterate that this action pertains specifically to the unreasonable risk
determination for TCE. While EPA intends to consider and may take additional similar actions
on other of the first ten chemical substances with completed TSCA section 6 risk evaluations,
EPA is taking a chemical-specific approach to revising the risk determination of this risk
evaluation and is incorporating new policy direction in a surgical manner, while being mindful of
Congressional direction on the need to complete risk evaluations and move toward any
associated risk management activities. Regarding public communication and interpretation of
risk, EPA has emphasized, in both the Federal Register Notice and the final revised unreasonable
risk determination, the conditions of use that drive the unreasonable risk for TCE, as well as
listing the conditions of use that do not.

With respect to impacts from this revised unreasonable risk determination on risk management
of TCE, EPA will propose a regulatory action with requirements under TSCA section 6(a) to the
extent necessary so that TCE no longer presents unreasonable risk. The public will have an
opportunity to comment on the proposed regulatory action, and EPA will consider such public

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comments and any additional information before finalizing the rulemaking. As a result, EPA
expects that impacts to TCE-containing articles, including consideration of replacement parts and
articles under TSCA section 6(c)(2)(D) and (E), will be considered during rulemaking. EPA
encourages the commenter to submit specific comments about regulatory impacts on TCE-
containing articles during the future public comment period for the TCE risk management rule.

Section 3 - Legal issues

Other comments discussing legal issues with the whole chemical approach, including its
consistency with TSCA, are discussed below in Section 4.1.

Section 3.1 - Statutory authority and TSCA section 26

A few commenters provided feedback on EPA's statutory authority under TSCA. Three industry
trade organizations or coalitions (0133, 0134, 0137) stated that EPA's proposed approach does
not comply with TSCA section 26 and section 6 requirements that risk evaluations be consistent
with best available science and based on the weight of the scientific evidence. One of the
commenters (0133) added that the legislative record for the TSCA amendments also does not
support EPA's new policy direction.

An industry trade organization (0137) provided its view that EPA's final risk evaluation for TCE
is predicated on a systematic review method that does not meet the scientific standards under
TSCA section 26. The industry trade organization discussed how, in May 2018, EPA released a
document titled "Application of Systematic Review in TSCA Risk Evaluations" (2018 SR
Document) and stated that, rather than incorporating and adapting existing methodologies that
represented the best available science at the time, the use of the approach in the 2018 SR
Document led to pervasive problems in the first ten risk evaluations. The commenter stated that
EPA's updates do not resolve the issue that the systematic review method underlying TCE's final
risk evaluation may have contravened TSCA section 26. The industry trade organization stated
that it does not agree that EPA may implement the proposed changes without amending the
scientific analysis in the final risk evaluation for TCE, providing its view that EPA must justify
these changes with additional analysis. The commenter stated the view that the final risk
evaluation for TCE was of low quality. The industry trade organization commented its view that
EPA conduct a robust systematic review and update the risk evaluation as warranted based on
the review in order to satisfy the requirements of TSCA sections 26(h) and (i).

An industry trade organization (0138) stated that EPA did not use best available science for the
TCE risk determination in its dermal risk assessment approach. The industry trade organization
commented that recognition of standard work practices and reliance on reasonable and realistic
exposure data are critical to meet the statutory requirements of TSCA, as well as the
"objectivity" criterion of the Information Quality Act and provided its view that EPA's reliance
on hypothetical assumptions for modeling of the amount of TCE that is absorbed by workers
from dermal contact cannot be justified. The commenter stated its view that EPA's use of
unrealistic dermal exposure assumptions has led to erroneous conclusions regarding the health
risks to workers using TCE in closed systems. The commenter (0138) also stated that the 2020
TCE risk evaluation also improperly relied on a 2003 Johnson et al. study, which they described
as contrary to EPA Science Advisory Committee on Chemicals (SACC) in 2020 and NASEM
recommendations. The industry trade organization added that NASEM was critical of the risk

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evaluation's weight of scientific evidence analysis. Another industry trade organization (0140)
similarly stated its position that the 2020 TCE risk evaluation fails to meet TSCA's best
available science standard and should not be relied upon. The commenter stated that SACC and
NASEM have raised concerns over the 2020 risk evaluation's methodology. The commenter
quoted NASEM's criticisms of the risk evaluation, stating that the systematic review of multiple
studies within the TCE risk evaluation "did not perform positively" on the assessment of
multiple systematic review measurement tool (AMSTAR-2) and that AMSTAR-2 should be used
for any subsequent risk evaluation.

Further, the trade association (0140) disagreed with EPA's decision to post a memo for an
existing chemical exposure limit (ECEL) for risk management under TSCA based on the
developmental toxicity endpoint. The commenter stated that the use of this endpoint violates the
scientific standards mandated in TSCA Section 26, as the endpoint is based on a study which the
commenter described as being criticized and rejected by the Agency's own advisory groups. The
commenter concluded that EPA should withdraw the alternative ECEL document and that risk
management options should be based on the conclusions for acute immunosuppression and
chronic autoimmunity.

EPA RESPONSE:

The final revised unreasonable risk determination for TCE is based on the peer reviewed risk
characterization in the November 2020 TCE Risk Evaluation, based on reasonably available
information pursuant to TSCA section 26(k) and 40 CFR 702.33, and developed in accordance
with TSCA section 26(h) and (i) to make decisions under TSCA section 6 in a manner consistent
with the best available science and based on the weight of scientific evidence. While EPA has
undertaken efforts to refine its 2018 approach to systematic review by developing a draft
systematic review protocol that has undergone review by NASEM, the draft protocol is not a
final document. EPA expects to use chemical-specific protocols in the future that are reflective
of what the Agency learned in this and the SACC peer review process and public comment. EPA
does not expect to apply adjustments retroactively; retroactive application would lead to further
delays in completing the risk evaluations for the first ten substances contrary to Congressional
intent. Thus, EPA maintains that the November 2020 TCE Risk Evaluation meets TSCA section
26(h) and (i) requirements. The policy changes described in the Federal Register Notice
announcing the availability of the draft revised risk determination for TCE do not amend or
impact the underlying data and analysis presented in the risk characterization of the November
2020 TCE Risk Evaluation. The policy changes do not impact the characterization of risk
estimates by condition of use (summarized in Section 4 of the final risk evaluation), or the
occupational exposures to workers and ONUs (summarized in Section 2.3 of the final risk
evaluation). Further discussion of EPAs consideration of workplace practices and
implementation of OSHA-compliant standard operating procedures is in section 5.2 of this
document.

In response to the commenter's assertion about the legislative record to support EPA's new
policy direction, Congress was clear that TSCA provides EPA broad authority to regulate
existing chemicals and delegated to EPA responsibility for implementing and overseeing a
process to conduct risk evaluations to "determine whether a chemical substance presents an
unreasonable risk of injury to health or the environment.. .under the conditions of use." See, e.g.,
S. REP. 114-67 (2015); 15 U.S.C. 2605(b)(4)(A). Fully consistent with that delegation, EPA

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expects that its interpretation of 40 CFR 702.47 will provide greater flexibility in the Agency's
ability to evaluate and manage unreasonable risk from individual chemical substances. Further
support for the whole chemical approach is in section 4.1.1. In response to comments asserting
that EPA's risk evaluation does not meet the standards of TSCA section 26 (0138, 0140), EPA
emphasizes that the Agency is not amending the underlying scientific analysis. EPA also views
the peer reviewed hazard and exposure assessments and associated risk characterization as robust
and upholding the standards of best available science and weight of the scientific evidence per
TSCA sections 26(h) and (i).

EPA disagrees with the characterization of the peer review of TCE by the trade association
commenter (0140). In the review of studies for the basis of the congenital heart defects (CHD)
endpoint, the SACC members had differences in opinion on the suitability of the evidence.
Additional detail regarding the summary of SACC comments on the peer review can be found in
the TCE 2020 Response to Comment.1 There was not a consensus viewpoint from the SACC,
and EPA has appropriately included the CHD studies. In considering the conflicting evidence
and varied opinions concerning the validity and relevance of the CHD database, EPA included
text throughout the the 2020 Risk Evaluation acknowledging the uncertainties associated with
this endpoint (Appendix F.l, Section 3.2.4.1.6, Section 3.2.5.3.1, Section 3.2.5.1.6, and Section
3.2.6.1). EPA acknowledges that while there is qualitative support for the CHD endpoint, based
on uncertainties in the dose-response for this endpoint and other considerations immune
endpoints were selected as the best overall endpoints for risk conclusions (Sections 3.2.5.4.1,
3.2.6.1.1). EPA explains in the 2020 Risk Evaluation the various biological factors that may lead
to increased susceptibility to CHDs, (e.g., maternal age). Therefore, CHDs are classified as a
PESS consideration and the associated POD and risk estimates are included in the RE in
consideration of PESS groups. EPA has accounted for CHD effects in risk characterization. EPA
also notes that 40 CFR 702.43(a)(1) states that "EPA will: (1) Integrate the hazard and exposure
assessments into quantitative and/or qualitative estimates of risk for the identified populations
(including any potentially exposed or susceptible subpopulation(s)) ..." And "(5) Describe the
weight of the scientific evidence for the identified hazards and exposures."

Regarding the commenter's statements regarding an ECEL based on the CHD endpoint (0140),
this issue relates to risk management, rather than this revised risk determination. EPA developed
an ECEL based on the immune endpoints2 and an ECEL based on the CHD endpoint3 in support
of risk management, and provided both of these documents in the public docket separate from
the draft revised unreasonable risk determination. The public will have an opportunity to
comment on the forthcoming proposed regulatory action for TCE, and EPA will consider such
public comments and any additional information as part of the proposed regulatory action before
finalizing the rulemaking.

1	Summary of External Peer Review and Public Comments and Disposition for Trichloroethylene (TCE) Response
to Support Risk Evaluation of Trichloroethylene (TCE), November 2020, EP A-HQ-OPPT-20.1.9-0500-0.1. .1.4.

2	EPA. Existing Chemical Exposure Limit (ECEL) (Autoimmunity) for Occupational Use of Trichloroethylene
(2022). EPA-HO-OPPT-2020-0642-0024.

3	EPA. Second Existing Chemical Exposure Limit (ECEL) (Developmental Toxicity) for Occupational Use of
Trichloroethylene (2022). EPA-HO-QPPT-2020-0642-0025.

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Section 3.2 - Process of revising the risk determination

EPA received comments related to the process of revising the risk determination. An industry
trade organization (0133) requested that EPA withdraw the draft revision to the risk
determination and provide an explanation for the proposed changes and additional public
comment opportunity before applying the changes. Furthermore, the commenter believes the
whole chemical approach lacks clarity and will have substantial impacts on future chemical
analysis.

Similarly, another industry trade organization (0137) commented that EPA did not adequately
support its decision to apply the whole chemical approach and not to assume workers' use of
PPE in EPA's draft revision to the risk determination for cyclic aliphatic bromide cluster
(HBCD). The commenter added that EPA also did not adequately respond to some HBCD
commenters' concerns raised in the HBCD docket. The commenter stated its view that the TCE
draft revision lacks support in the same way as the commenter indicated that the HBCD revision
did.

An advocacy organization (0135) discussed at length that the Kisor case (Kisor v. Wilkie, 139 S.
Ct. 2400 (2019)) cannot be applied to question the viability of the whole chemical approach as
the Supreme Court in this case reaffirmed the long-standing principle that courts must generally
defer to agencies' reasonable interpretations of their own ambiguous regulations, and that the list
of considerations provided by the Court in Kisor favors a reviewing court granting deference to
EPA on its whole chemical approach.

EPA RESPONSE:

The revised unreasonable risk determination for TCE is based on the peer reviewed risk
characterization of the November 2020 risk evaluation, which was developed according to the
TSCA section 26(h) requirement to make science-driven decisions, consistent with best available
science, and in accordance with the TSCA section 26(i) requirement to make decisions based on
the weight of scientific evidence. Changing the risk determination to a whole chemical approach
does not impact the underlying data and analysis presented in the risk characterization of the risk
evaluation.

The draft revised unreasonable risk determination for TCE was published in July 2022 along
with the Federal Register Notice explaining the whole chemical approach to the TCE risk
determination, and why EPA believes that a whole chemical approach to TCE better aligns with
TSCA's objective of protecting health and the environment. The draft revised unreasonable risk
determination also explained why EPA believes that not assuming the use of PPE or other
mitigating measures better aligns with TSCA. EPA understands that there could be occupational
safety protections in place at workplace locations; however, not assuming use of PPE reflects
EPA's recognition that unreasonable risk may exist for subpopulations of workers that may be
highly exposed because they are not covered by Occupational Safety and Health Administration
(OSHA) standards, or their employers are out of compliance with OSHA standards, or because
many of OSHA's chemical-specific permissible exposure limits largely adopted in the 1970's
are—as noted by OSHA—"outdated and inadequate for ensuring protection of worker health,4"

4 As noted on Occupational Safety and Health Administration. Permissible Exposure Limits - Annotated Tables.
Accessed June 13, 2022. https://www.osha.gov/an.notated-peis.

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or because EPA finds unreasonable risk for purposes of TSCA notwithstanding OSHA
requirements. In response to the commenter requesting an additional public comment
opportunity (0133), EPA provided notice and an opportunity for public comment on the draft
revised risk determination for TCE and the approach described in the Federal Register Notice.
Further discussion of EPA's consideration of PPE use and OSHA standards are in section 4.2 of
this document.

EPA has responded to the comments received on the draft revised unreasonable risk
determination for HBCD (EPA-HQ-OPPT-2019-0237-0124)). In that document for HBCD and
below, for TCE, EPA provides an expanded explanation of why the whole chemical approach to
TCE better aligns with TSCA objectives (including listing of the conditions of use that do and do
not drive the unreasonable risk for TCE as a whole chemical substance) and the rationale behind
not assuming the use of PPE in the TCE unreasonable risk determination.

With respect to EPA's approach to changing the TCE risk determination, the revised Section 5 of
the TCE Risk Evaluation is sufficient to describe the determination of unreasonable risk of TCE
as a "whole chemical substance" and to explain the change in approach regarding assuming use
of PPE by workers. As mentioned, the whole chemical risk determination approach does not
impact the underlying data and analysis presented in the risk characterization of the TCE Risk
Evaluation. The risk evaluation already includes exposure analysis with and without PPE. Table
4-59 in the risk evaluation presents risk estimates for each COU with and without PPE. EPA has
made no changes to this scientific analysis. The Agency believes that the revised risk
determination is sufficiently clear that it supersedes any conflicting statements in the November
2020 risk evaluation that it is neither necessary nor an appropriate use of resources to reissue the
entire risk evaluation.

EPA appreciates comments concerning the application of Kisor v. Wilkie, 139 S. Ct. 2400
(2019), to EPA's draft revised unreasonable risk determination for TCE. Similar to the
commenter's view, EPA maintains that its interpretation of 40 CFR 702.47 as permitting the
issuance of either COU-specific or whole chemical risk determinations is a reasonable
interpretation of that regulation and would be entitled to Auer (see Auer v. Robbins, 117 S.Ct.
905 (1997)) deference when using the multifactor test set forth in Kisor.

Section 4 - Revisions to the risk determination

Section 4.1 - Whole chemical approach vs. individual condition of use (COU)

Section 4.1.1 - Support for the whole chemical approach

Several non-governmental environmental and health advocacy organizations (0135, 0144) and a
union (0141) in expressing support for the whole chemical approach for TCE, stated their view
that the approach is consistent with the language and purpose of TSCA. One advocacy
organization (0144) stated that TSCA requires whole chemical determinations of unreasonable
risk to satisfy the mandate to integrate and assess available information on hazards and exposures
from the COU, especially in cases of PESS, multiple routes of exposure, and combined risk to
exposed populations across the chemical's COUs and life-cycle stages. The commenter added
that a whole chemical unreasonable risk determinations is also more efficient and straightforward
than using a COU-specific approach, reasoning that EPA both could choose not to regulate

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conditions of use the Agency finds to be safe and could issue clear statements with respect to the
safe conditions of use for the chemical at issue. Similarly, a product manufacturer (0143)
requested that EPA confirm that adopting a whole chemical approach would not inhibit EPA's
future risk management rulemakings on continued uses of TCE, for instance, taking into
consideration critical use exemptions for specific conditions of use of a chemical under TSCA
section 6(g).

The two advocacy organizations (0135, 0144) also commented that TSCA unambiguously
mandates EPA to conduct a whole chemical risk determination as the language of the statute
referencing decision-making for a chemical substance dictates that EPA cannot segment its
determination into separate findings of unreasonable risk for some conditions of use and no
unreasonable risk for others. One of the advocacy organizations (0135) stated its view that EPA
should take a whole chemical approach for all chemicals' future risk determination to fulfill
TSCA's mandate that EPA identify the full risk posed by each chemical.

A union (0141) stated that a whole chemical approach would ensure that all workers exposed to
unreasonable risks from TCE can be provided equivalent protections under TSCA.

Some commenters (0135, 0144) stated that EPA is correct to rely on the 2019 Ninth Circuit's
interpretation of the governing regulation in Safer Chemicals v. EPA to conduct a whole
chemical risk determination.

EPA RESPONSE:

EPA appreciates the comments in support of the whole chemical approach. As EPA explained in
the Federal Register Notice announcing the availability of the draft revised risk determination for
TCE, notwithstanding EPA's choice to issue COU-specific risk determinations to date, EPA
interprets its risk evaluation regulation to also allow the Agency to issue whole chemical risk
determinations. Either approach is permissible under the regulation, and the Ninth Circuit Court
of Appeals also recognized the ambiguity of the regulation on this point in Safer Chemicals et al.
v. EPA (943 F.3d 397 (9th Cir. 2019). EPA plans to consider the appropriate approach for each
chemical substance risk evaluation on a case-by-case basis, taking into account considerations
relevant to the specific chemical substance in light of the Agency's obligations under TSCA.
EPA expects that this case-by-case approach will provide greater flexibility to evaluate and
manage unreasonable risk from individual chemical substances as required under TSCA. EPA
anticipates that this flexibility will better serve TSCA's objectives by helping ensure that EPA is
best positioned to present, and initiate risk management to address, chemical-specific
unreasonable risk determinations. EPA believes this is a reasonable approach under TSCA and
the Agency's implementing regulations.

For TCE, the whole chemical approach is appropriate because there are benchmark exceedances
for a substantial number of conditions (52 of the 54 evaluated) of use spanning across the
chemical lifecycle-from manufacturing (including import), processing, industrial and
commercial use, consumer use, and disposal) for workers, occupational non-users (ONUs),
consumers, and bystanders. In addition to the breadth of identified risk, EPA also considered the
severity of the health effects associated with TCE exposures, including cancer, chronic non-
cancer, and acute effects. Because these chemical-specific health hazards and exposures cut
across the conditions of use within the scope of the risk evaluation, a substantial number of
conditions of use drive the unreasonable risk, and the Agency is better positioned to achieve its

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TSCA objectives for TCE when issuing a whole chemical determination for TCE, it is
appropriate for the Agency to make a determination that the whole chemical presents an
unreasonable risk.

EPA agrees that a whole chemical approach will help ensure the public, including workers, is
protected from unreasonable risks from chemicals in a way that is supported by science and the
law, and appreciates the commenter's support.

In response to the comment that risk management activities could be tailored to individual
conditions of use, EPA notes that, in the final revised risk determination, EPA identifies which
conditions of use drive the unreasonable risk of TCE. Consistent with the statutory requirements
of TSCA section 6(a), EPA would propose risk management actions to the extent necessary so
that TCE no longer presents an unreasonable risk. Therefore, it is expected that EPA's risk
management actions will focus on the conditions of use that drive the unreasonable risk.
However, it should be noted that, under TSCA section 6(a), EPA is not limited to regulating the
specific activities found to drive unreasonable risk and may select from among a suite of risk
management requirements in section 6(a) related to manufacture (including import), processing,
distribution in commerce, commercial use, and disposal as part of its regulatory options to
address the unreasonable risk. For example, EPA may regulate upstream activities (e.g.,
manufacturing, processing, distribution in commerce) in order to address downstream activities
driving unreasonable risk (e.g., consumer use) even if the upstream activities do not drive the
unreasonable risk.

EPA appreciates the comment (0143) requesting that EPA take into consideration critical use
exemptions for specific conditions of use of a chemical under TSCA section 6(g) and also
appreciates the information provided by the commenter requesting a TSCA section 6(g)
exemption. This information is helpful to inform risk management action on TCE. Additionally,
under TSCA section 6(c)(2)(C), in deciding whether to prohibit or restrict in a manner that
substantially prevents a specific condition of use of a chemical substance or mixture, and in
setting an appropriate transition period for such action, EPA must consider, to the extent
practicable, whether technically and economically feasible alternatives that benefit human health
or the environment will be reasonably available as a substitute when the proposed prohibition or
other restriction takes effect. The public will have an opportunity to comment on the proposed
regulatory action, and EPA will consider such public comments and any additional information
and the proposed regulatory action before finalizing the rulemaking.

Section 4.1.2 - Opposition to the whole chemical approach

Some commenters, including industry trade associations (0135, 0133, 0142), opposed the whole
chemical approach for unreasonable risk determination. Their comments included:

•	EPA has not supported its claim that its whole chemical approach to risk determinations
is science-based and has provided no science-based support for why a majority of COUs
should trigger a whole chemical unreasonable risk determination (0133).

•	The whole chemical approach would have substantial unintended consequences,
including prolonged uncertainty for the regulated community, non-science-based market

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impacts, and the continued use of resources to research uses which pose no risk (0133,
0135).

• The whole chemical approach would result in a negative finding on uses that may not
have an unreasonable risk, regrettable substitutions as manufacturers seek to quickly
implement functional alternatives, and public confusion, as the public will not know
which uses are safe and which pose risk (0133, 0135).

Another industry trade organization (0142) stated its view that EPA should continue to make
COU-specific risk determinations for TCE and other chemical substances, because such an
approach is grounded in the statute and regulations and supported by sound science. This
commenter said that using the whole chemical approach fails to provide the clarity of EPA's
decision-making regarding the risks presented and not presented by TCE that the COU-specific
determinations in the November 2020 risk evaluation provided, and would result in skewed
understandings of the risk of chemical substances.

Finally, an industry trade organization (0135) commented that applying a COU-specific
approach allows stakeholders and EPA to focus more efficiently on uses that in fact pose
unreasonable risks.

EPA RESPONSE:

As EPA explained in the Federal Register Notice announcing the availability of the draft revised
risk determination for TCE, EPA acknowledges a lack of specificity in the statute and
inconsistency in the regulations with respect to the presentation of risk determinations in TSCA
section 6 risk evaluations. Notwithstanding EPA's choice to issue COU-specific risk
determinations to date, EPA interprets its risk evaluation regulation to also allow the Agency to
issue whole chemical risk determinations. Either approach is permissible under the regulation.

In response to commenters' assertions that EPA has not supported the claim that the whole
chemical approach to risk determination is science-based, EPA emphasizes that the revised
unreasonable risk determination for TCE is based on the peer reviewed risk characterization in
the November 2020 TCE Risk Evaluation, based on reasonably available information pursuant to
TSCA section 26(k) and 40 CFR 702.33, and developed in accordance with TSCA section 26(h)
and (i) to make decisions under TSCA section 6 in a manner consistent with the best available
science and based on the weight of scientific evidence.

EPA has articulated the basis for a whole chemical approach to TCE in detail in the Federal
Register Notice announcing the availability of the draft revised risk determination for TCE. As
explained therein, the Agency has inherent authority to replace, revise, reconsider, or repeal
previously made decisions to the extent permitted by law, with a reasoned explanation. FCC v.
Fox Television Stations, Inc., 556 U. S. 502, 515 (2009); see also Motor Vehicle Mjrs. Ass 'n v.
State Farm Mutual Auto. Ins. Co., 463 29, 42 (1983). The revised unreasonable risk
determination for TCE reflects EPA's objective of conducting a technically sound, manageable
evaluation to determine whether the chemical substance—not just individual uses or activities—
presents an unreasonable risk. EPA plans to consider the appropriate approach for each chemical
substance risk evaluation on a case-by-case basis, taking into account considerations relevant to
the specific chemical substance. In the case of TCE, 52 of the 54 conditions of use drive the
unreasonable risk and the chemical-specific properties cut across the conditions of use within the

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scope of the risk evaluation; therefore, EPA has concluded that the risk determination for TCE is
better characterized by the whole chemical approach. EPA believes this is a reasonable approach
under TSCA and the Agency's implementing regulations.

Responding to commenters' ideas concerning conditions of use which were identified in the
November 2020 TCE Risk Evaluation as not presenting unreasonable risk, and what commenters
describe as the benefits of a COU-specific approach, in this final revised risk determination, EPA
identifies which conditions of use drive the unreasonable risk and which conditions of use do not
drive the unreasonable risk of TCE. Consistent with the statutory requirements of TSCA section
6(a), EPA will propose risk management actions to the extent necessary so that TCE no longer
presents an unreasonable risk. EPA expects to focus its risk management action on the conditions
of use that drive the unreasonable risk. EPA does not expect that the issuance of a whole
chemical risk determination for TCE will affect the efficiency of EPA's risk management
rulemaking. However, it should be noted that, under TSCA section 6(a), EPA is not limited to
regulating the specific activities found to drive unreasonable risk and may select from among a
suite of risk management requirements in section 6(a) related to manufacture (including import),
processing, distribution in commerce, commercial use, and disposal as part of its regulatory
options to address the unreasonable risk. As a general example, EPA may regulate upstream
activities (e.g., manufacturing, processing, distribution in commerce) in order to address
downstream activities (e.g., consumer uses) driving unreasonable risk even if the upstream
activities do not drive the unreasonable risk.

Furthermore, there is no change in the underlying TCE risk characterization with regard to
conditions of use that may relate to articles. Under TSCA section 6(c)(2)(E), any relevant
consideration of articles will take place during the risk management rulemaking stage, based on
the risk evaluation findings. The public will have an opportunity to provide comments and any
additional information during the comment period of the proposed risk management rule.

Section 4.1.3 - Inconsistency with TSCA and Risk Evaluation Rule

Several industry trade organizations (0135, 0133, 0142) provided their view that a whole
chemical approach is inconsistent with TSCA and its implementing regulations.

Basis for the whole chemical approach

Two industry trade organizations (0133, 0142) cited TSCA section 6(b)(4)(F)(i) and (iv) and
stated that EPA must integrate and assess available information on hazards and exposures for the
COUs of the chemical substance and consider the likely duration, intensity, frequency and
number of exposures under the COUs. Another industry trade organization (0136) claimed that
TSCA requires that changes in approach have scientific support, citing TSCA section 26 and
stating that EPA did not provide a scientific basis for the whole chemical approach.

An industry trade organization (0137) stated that EPA's whole chemical approach for
unreasonable risk determination is based on hazard rather than risk and thus contrary to TSCA.
The commenter provided its view that the Risk Evaluation Rule requires that risk evaluations be
comprehensive and thus that risk determinations must be based on all conditions of use rather
than driven by a subset of uses. The commenter further described at length their position that
EPA used a hazard-based approach because the Agency did not consider aggregate exposures

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Response to Public Comments Received

across conditions of use under TSCA section 6(b)(4)(F)(ii) in its 2020 final risk evaluation for
TCE and did not consider risk holistically, as would be required in a risk characterization. The
commenter also stated that a whole chemical risk determination would be less useful than COU-
specific ones, and thus that such an approach is contrary to TSCA section 6(b).

An industry trade organization (0133) commented that language in the HBCD final risk
determination and TCE draft revised risk determination departs from the draft revisions to the
risk determinations for HBCD and PV29. The commenter stated that EPA's use of "substantial
amount" of conditions of use to support application of a whole chemical approach is more
arbitrary than the "majority" of conditions language used in the earlier draft revisions. The
industry trade organization stated its view that this "substantial amount" term is inconsistent with
TSCA section 26's requirements that section 6 decisions be grounded in science and thus that
EPA's revision lacks a reasoned explanation.

Inconsistency with TSCA

Several commenters wrote that the draft revision is inconsistent with TSCA. An industry trade
organization (0142) stated its view that a whole chemical approach would functionally disable
TSCA section 6(c)(2)(E), as well as Congress' intent for including it, since the provision makes
clear that the extent to which articles should be regulated is dictated by what risks a risk
evaluation identifies as stemming from exposure to a chemical substance in an article, and
articles should not be regulated to ameliorate risk presented by other conditions of use.

Additionally, the industry trade organization (0142) stated that the whole chemical approach is
inconsistent with the structure created by Congress in the Lautenberg Amendments to TSCA in
2016. Specifically, the commenter said that future risk evaluations will be conducted for
chemical substances that EPA has already determined "may present" an unreasonable risk
through the prioritization process. The commenter stated that if the whole chemical approach is
used, the distinction between the "may present" an unreasonable risk standard for prioritization
and the "presents" standard for triggering risk management regulations would be lost.

The commenter, as well as another industry trade organization (0133) stated that the practical
effect of the whole chemical approach is that there are unlikely to be any determinations of no
unreasonable risk. The commenters stated their view that the whole chemical approach thus
impermissibly renders parts of the statute - the provisions for a finding of no unreasonable risk -
superfluous. The industry trade organizations stated that the inclusion in the statute of provisions
for a finding of no unreasonable risk, including, for example, TSCA section 18(a)(l)(B)(i), is
evidence that Congress must have intended for specific COUs to be evaluated by the Agency and
risk determinations made for each of those uses. On the other hand, an advocacy organization
(0135) discounted this position, providing its view that whether industry actors believe that a
whole chemical approach may result in fewer findings of "no unreasonable risk" has no bearing
on the legitimacy of EPA's approach under TSCA.

Another industry trade organization (0136) stated that, because this approach would result in all
evaluated chemicals receiving an unreasonable risk determination, it would effectively render
superfluous TSCA's preemption provision regarding cases of no unreasonable risk.

Similarly, two industry trade organizations (0135, 0133) also stated their view that if the
individual COU approach for unreasonable risk determination is no longer employed, then any

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opportunity for obtaining the federal preemption of state or local requirements provided for
under TSCA Section 18(a) for COUs that pose no unreasonable risk would either be delayed by
years until EPA promulgated a final risk management rule or potentially eliminated depending
on the scope of the risk management rule. One commenter (0135) noted that the consequence of
allowing states to issue chemical regulations while EPA assesses a chemical and until EPA
issues a final risk management rule could create an unworkable and confusing set of
requirements for any sector.

In contrast, an advocacy group (0144) stated that in the final revised risk determination for
HBCD, EPA overstated the preemptive effect on state chemical regulation of risk management
rules based on whole chemical risk evaluations. The commenter asserted that, under TSCA
section 18(c)(3), states are not preempted from regulating risks, hazards, or conditions of use that
EPA does not restrict pursuant to TSCA section 6(a), regardless of whether they were evaluated
in the final risk evaluation. The commenter provided its view that the scope of preemption is
defined by the requirements of the section 6(a) risk management rules rather than the contents of
the earlier risk evaluations.

Additionally, an industry trade organization (0136) commented that the whole chemical
approach would contravene policies in TSCA section 3 that direct EPA to not impede unduly or
create unnecessary economic barriers to technological innovation.

Inconsistency with the Risk Evaluation Rule

An industry trade organization (0137) stated its view that EPA improperly dismissed a statement
from the Risk Evaluation Rule regarding COU-specific determinations without providing
sufficient regulatory language or rationale to support its departure from that statement. Further,
the commenter stated that any ambiguity in the Final Risk Evaluation Rule as to whole chemical
risk determinations should be understood as whether whole chemical determinations can
supplement, rather than replace, COU-specific determinations.

The industry trade association (0137) commented in part with a hypothetical example that it is
unreasonable and contrary to 40 C.F.R. § 702.49(c) for EPA to issue a whole chemical
unreasonable risk determination when two conditions of use do not present an unreasonable risk.
The commenter added that it might be appropriate to issue a whole chemical unreasonable risk
determination in addition to individual COU-determinations, but this would only be appropriate
if EPA concluded that the aggregate exposures across all conditions of use would present
unreasonable risks.

EPA RESPONSE:

EPA followed the requirements under TSCA section 6(b)(4) in issuing this revised unreasonable
risk determination for TCE, including all requirements for a risk evaluation under TSCA section
6(b)(4)(F). Specifically, Section 4 of the final risk evaluation describes how EPA integrated and
assessed reasonably available information on hazards and exposures for the conditions of use for
TCE (considering factors such as environmental releases, environmental monitoring and
biomonitoring, as well as toxicity testing and physical and chemical properties), as well to
workers, occupational non-users, consumers, and bystanders, using reasonably available data,
including modeling.

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Regarding the comment that risk evaluations should be comprehensive and thus be based on all
conditions of use, in accordance with TSCA section 6(b)(4)(A), EPA evaluates chemical
substances to determine whether they present unreasonable risk under the conditions of use. The
risk evaluation for TCE encompasses the conditions of use within the scope of the risk
evaluation. As set forth in the revised risk determination, EPA has determined that TCE, as a
whole chemical substance, presents an unreasonable risk of injury to health when evaluated
under its conditions of use.

As EPA explained in the Federal Register Notice announcing the availability of the draft revised
risk determination for TCE, EPA plans to consider the appropriate approach for each chemical
substance risk evaluation on a case-by-case basis, taking into account considerations relevant to
the specific chemical substance in light of the Agency's obligations under TSCA.

Regarding the comment that TSCA requires that changes in approach have scientific support,
EPA notes that the revised unreasonable risk determination for TCE is based on the peer
reviewed risk characterization in the November 2020 TCE Risk Evaluation, based on reasonably
available information pursuant to TSCA section 26(k) and 40 CFR 702.33, and developed in
accordance with TSCA section 26(h) and (i) to make decisions under TSCA section 6 in a
manner consistent with the best available science and based on the weight of scientific evidence.

EPA emphasizes that the Agency is not amending the underlying scientific analysis. EPA also
views the peer reviewed hazard and exposure assessments and associated risk characterization as
robust and upholding the standards of best available science and weight of the scientific evidence
per TSCA sections 26(h) and (i). (87 FR 40520 (July 7, 2022)). The policy changes do not
impact the characterization of risk estimates by condition of use (and summarized in Section 4.2
of the final risk evaluation), or the occupational exposures to workers and ONUs (and
summarized in Section 2.3 of the final risk evaluation), including an explanation of the different
exposures between workers and ONUs, given the different tasks workers perform under each
condition of use. EPA also notes that the assertion that the Agency based its determination on
hazard alone is not correct; the revised unreasonable risk determination is based on both the
hazard of the chemical substance and the exposures or environmental releases, as described in
Sections 3 and 2, respectively, of the November 2020 TCE Risk Evaluation, and further
explained in Sections 5.2 and 5.3 of the revised unreasonable risk determination. EPA disagrees
that a whole chemical approach is appropriate only for an aggregate assessment.

The revised unreasonable risk determination for TCE reflects EPA's objective of conducting a
technically sound, manageable evaluation to determine whether the chemical substance—not just
individual uses or activities—presents an unreasonable risk. In this instance a "substantial
amount" of conditions of use that drive the unreasonable risk encompasses 52 out of the 54
conditions of use of TCE. A "substantial amount" of conditions of use driving the unreasonable
risk is just one of the chemical-specific reasons why EPA is making a whole chemical
unreasonable risk determination for TCE. Moreover, for TCE, those conditions of use span the
lifecycle of the chemical substance—from manufacturing (including import), processing,
industrial and commercial use, consumer use, and disposal for worker, ONU, consumer, and
bystander health, and the severity of the health effects associated with TCE exposures. Since
these chemical-specific properties cut across the conditions of use within the scope of the risk
evaluation, the Agency's risk findings and conclusions encompass a substantial amount of the
conditions of use and the Agency is better positioned to achieve its TSCA objectives for TCE

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when using a whole chemical unreasonable risk determination for TCE, EPA concludes that the
Agency's risk determination for TCE is better characterized as a whole chemical risk
determination rather than COU-specific risk determination. In the case of TCE, 52 out of 54
conditions of use drive the unreasonable risk and the chemical-specific properties cut across the
conditions of use within the scope of the risk evaluation; therefore, EPA has concluded that the
risk determination for TCE is better characterized by the whole chemical approach. EPA believes
this is a reasonable approach under TSCA and the Agency's implementing regulations, including
requirements under TSCA section 26(h) and (i) that section 6 decisions are consistent with the
best available science and are supported by the weight of scientific evidence.

As explained in the Federal Register Notice to the draft revised unreasonable risk determination
for TCE, EPA has the inherent authority to reconsider previous decisions when permitted by law
and supported by reasoned explanation. FCC v. Fox Television Stations, Inc., 556 U.S. 502, 515
(2009); see also Motor Vehicle Mjrs. Ass'nv. State Farm Mutual Auto. Ins. Co., 463 U.S. 29, 42
(1983). EPA acknowledges a lack of specificity in the statute and inconsistency in the
regulations with respect to the presentation of risk determinations in TSCA section 6 risk
evaluations. In the November 2020 TCE Risk Evaluation, EPA applied 40 CFR 702.47 based on
one particular passage in the preamble to the final Risk Evaluation Rule,5 which stated: "The
final step of a risk evaluation is for EPA to determine whether the chemical substance, under the
conditions of use, presents an unreasonable risk of injury to health or the environment. EPA will
make individual risk determinations for all uses identified in the scope. This part of the
regulation is slightly amended from the proposed rule, to clarify that the risk determination is
part of the risk evaluation, as well as to account for the revised approach to [sic] that ensures
each COU covered by the risk evaluation receives a risk determination." 82 FR 33726, 33744.
However, in contrast to this portion of the preamble of the final Risk Evaluation Rule, 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. The text of 40 CFR 702.47 states: "[a]s part of
the risk evaluation, EPA will determine whether the chemical substance presents an
unreasonable risk of injury to health or the environment under each condition of uses [sic] within
the scope of the risk evaluation, either in a single decision document or in multiple decision
documents" (emphasis added). Other language reiterates this perspective. For example, 40 CFR
702.31(a) states that the purpose of the rule is to establish 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). Likewise, there are
recurring references to whether the chemical substance presents an unreasonable risk in 40 CFR
702.41(a). Notwithstanding the one preambular statement about COU-specific risk
determinations, the preamble to the final rule also contains support for a risk determination on
the chemical substance as a whole. In discussing the identification of the conditions of use of a
chemical substance, the preamble notes that this task inevitably involves the exercise of
discretion on EPA's part, and, "[a]s EPA interprets the statute, the Agency is to exercise that
discretion consistent with the objective of conducting a technically sound, manageable

5 Procedures for Chemical Risk Evaluation Under the Amended Toxic Substances Control Act (82 FR 33726) (July
20, 2017).

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evaluation to determine whether a chemical substance—not just individual uses or activities—
presents an unreasonable risk." (82 FR at 33729).

Therefore, notwithstanding EPA's choice to issue COU-specific risk determinations to date, EPA
interprets its risk evaluation regulation to also allow the Agency to issue whole chemical risk
determinations. Either approach is permissible under the regulation, and the Agency's
interpretation is entitled to Auer deference when using the multifactor test set forth in Kisor. As
such, notice and comment rulemaking is not necessary before revising the TCE risk
determination.

The unreasonable risk determination does not consider costs or other nonrisk factors. In making
the unreasonable risk determination, EPA considers relevant risk-related 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 PESS); the severity of hazard (including the nature of the
hazard, the irreversibility of the hazard); and uncertainties. EPA takes into consideration the
Agency's confidence in the data used in the risk estimate. This includes an evaluation of the
strengths, limitations, and uncertainties associated with the information used to inform the risk
estimate and the risk characterization. Therefore, the TCE chemical unreasonable risk
determination takes in consideration the hazard of TCE and the exposures from all conditions of
use of TCE.

Furthermore, there is no change in the underlying TCE risk evaluation. EPA disagrees that a
COU-specific risk determination is more useful than a whole-chemical risk determination
because EPA has transparently described which conditions of use do or do not drive EPA's
determination. In the final revised risk determination, EPA identifies which conditions of use
drive the unreasonable risk of TCE. Consistent with the statutory requirements of TSCA section
6(a), EPA will propose risk management action to the extent necessary so that TCE no longer
presents an unreasonable risk. EPA expects to focus its risk management action on the conditions
of use that drive the unreasonable risk. However, it should be noted that, under TSCA section
6(a), EPA is not limited to regulating the specific activities found to drive unreasonable risk and
may select from among a suite of risk management requirements in section 6(a) related to
manufacture (including import), processing, distribution in commerce, commercial use, and
disposal as part of its regulatory options to address the unreasonable risk. As a general example,
EPA may regulate upstream activities (e.g., manufacturing, processing, distribution in
commerce) in order to address downstream activities (e.g., consumer uses) driving unreasonable
risk even if the upstream activities do not drive the unreasonable risk.

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

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section 6(a) rulemaking. For example, federal preemption applies even if EPA does not regulate
in that final rule a particular COU, as long as that COU was evaluated in the final risk evaluation.

Regarding the comment referencing TSCA section 6(c)(2)(E) and the concern regarding
regulation of articles, EPA notes that the Agency has not identified conditions of use of TCE that
include articles. If a condition of use included an article and it was determined to drive the
unreasonable risk, EPA would apply any prohibitions or restrictions consistent with TSCA
section 6(c)(2)(E) when regulating the unreasonable risk driven by an article. Specifically, EPA
emphasizes that there is no change in the underlying TCE risk evaluation nor in the proposed
revised risk determination for TCE with regard to conditions of use that may relate to
replacement parts or articles. The revised risk determination identifies conditions of use that
drive unreasonable risk from TCE. Under TSCA section 6(c)(2) (D) and (E), any relevant
consideration of replacement parts and articles will take place during the risk management
rulemaking stage, based on the risk evaluation findings. The public will have an opportunity to
provide comments and any additional information during the comment period of the proposed
risk management rule.

Similarly, in response to the comment regarding barriers to technological innovation, EPA notes
that TSCA section 2(b)(3) specifies that "authority over chemical substances and mixtures
should be exercised in such a manner as not to impede unduly or create unnecessary economic
barriers to technological innovation while fulfilling the primary purpose of [TSCA] to assure that
such innovation and commerce in such chemical substances and mixtures do not present an
unreasonable risk of injury to health or the environment." Consistent with the statutory
requirements of TSCA section 6(a), EPA will propose risk management action to the extent
necessary so that TCE no longer presents an unreasonable risk. As required by TSCA section
6(c)(2)(A), when proposing and promulgating a TSCA section 6(a) rule for TCE, EPA will
consider and publish a statement based on reasonably available information with respect to
factors including the reasonably ascertainable economic consequences of the rule. The
considerations related to reasonably ascertainable economic consequences include, but are not
limited to, considerations of the likely effect of the rule on the national economy, small business,
technological innovation, the environment, and public health.

EPA also notes that there are separate statutory standards and processes for designating chemical
substances as high-priority for risk evaluation and conducting TSCA risk evaluations. Under
TSCA section 6(b), EPA must designate as a high-priority substance "a chemical substance that
the Administrator concludes, without consideration of costs or other nonrisk factors, may present
an unreasonable risk of injury to health or the environment because of a potential hazard and a
potential route of exposure under the conditions of use, including an unreasonable risk to a
potentially exposed or susceptible subpopulation identified as relevant by the Administrator."
(TSCA section 6(b)(l)(B)(i)). EPA is required to consider statutorily-prescribed factors when
conducting prioritization and to provide several opportunities for public comment, and the
prioritization process must last between 9-12 months (TSCA section 6(b)(1)(A), (C)). Once EPA
designates a chemical substance as a high-priority substance for risk evaluation, EPA must then
initiate a longer 3- to 3.5-year risk evaluation process. Through that risk evaluation process, EPA
must "determine whether a chemical substance presents an unreasonable risk of injury to health
or the environment, without consideration of costs or other nonrisk factors, including an
unreasonable risk to a potentially exposed or susceptible subpopulation identified as relevant to

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the risk evaluation by the Administrator, under the conditions of use." (TSCA section
6(b)(4)(A)). That process is subject to separate statutory requirements and considerations
applicable to risk evaluations (e.g., TSCA section 6(b)(4)(D), (F)). If EPA finds unreasonable
risk through a risk evaluation, EPA must proceed to address that unreasonable risk through
TSCA section 6(a) risk management action. Although EPA must conduct a risk evaluation after
designating a chemical substance as a high-priority substance, and the reasonably available
information and findings informing prioritization will also inform EPA's risk evaluation on a
high-priority substance, the standards and processes for TSCA prioritization and risk evaluation
are separate and distinct.

Section 4.1.4 - Other comments on the whole chemical approach

Two industry trade organizations (0133, 0142) requested that EPA:

•	Review the whole chemical approach in the context of TSCA's risk-based decision-
making framework and requirements for risk management rules (0133);

•	Explain how the change to a whole chemical approach may affect risk management
(0133, 0142);

•	Develop principles and criteria that would dictate when and how the whole chemical
approach would be applied and when it would not (e.g., will it be applied if 50% of the
COUs show unreasonable risk? 10%? At least one?) (0133, 0142). How will EPA treat
the COUs that it determines do not present an unreasonable risk in its risk management
plan when a whole chemical approach has been taken? (0133); and

•	Explain how the whole chemical approach is employed in a manner consistent with the
best available science or a weight of scientific evidence approach or compelled by the
factors and standards dictated by Congress in the amendments to TSCA section 26
(0142).

EPA RESPONSE:

EPA appreciates other comments received in connection with the TCE draft revised
unreasonable risk determination. As stated previously, this action pertains only to the risk
determination for TCE. While EPA may consider similar actions on other first ten chemicals,
EPA is taking a chemical-specific approach to reviewing these risk evaluations and is
incorporating new policy direction in a surgical manner, while being mindful of Congressional
direction on the need to complete risk evaluations and move toward any associated risk
management activities.

The revised unreasonable risk determination for TCE is based on the peer reviewed risk
characterization of the November 2020 risk evaluation, which is based on reasonably available
information pursuant to TSCA section 26(k) and 40 CFR 702.33, and developed in accordance
with TSCA section 26(h) and (i) to make decisions under TSCA section 6 in a manner consistent
with the best available science and based on the weight of scientific evidence. Changing the risk
determination to a whole chemical approach does not impact the underlying data and analysis
presented in the risk characterization of the risk evaluation.

For TCE, the whole chemical approach is appropriate because there are benchmark exceedances

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for a substantial number of conditions of use (spanning across most aspects of the chemical
lifecycle-from manufacturing (including import), processing, industrial and commercial use,
consumer use, and disposal) for worker, ONU, consumer, and bystander health, and the severity
of the health effects associated with TCE exposures. Since these chemical-specific properties cut
across the conditions of use within the scope of the risk evaluation, the Agency's risk findings
and conclusions encompass a substantial amount of the conditions of use, and the Agency is
better positioned to achieve its TSCA objectives for TCE when using a whole chemical
unreasonable risk determination for TCE, EPA concludes that the Agency's risk determination
for TCE is better characterized as a whole chemical risk determination rather than COU-specific
risk determinations.

With respect to risk management, consistent with the statutory requirements of TSCA section
6(a), EPA will propose risk management action to the extent necessary so that TCE no longer
presents unreasonable risk. In the final revised risk determination for TCE, EPA has identified
the conditions of use that drive the unreasonable risk for TCE and will focus its risk management
efforts on addressing that unreasonable risk, as required by TSCA. Regarding how EPA may
treat the COUs that it determines do not drive the unreasonable risk, EPA notes that, under
TSCA section 6(a), EPA is not limited to regulating the specific activities found to drive
unreasonable risk and may select from among a suite of risk management options related to
manufacture, processing, distribution in commerce, commercial use, and disposal in order to
address the unreasonable risk. For instance, EPA may regulate upstream activities (e.g.,
manufacturing, processing, distribution in commerce) in order to address downstream activities
driving unreasonable risk (e.g., consumer use) even if the upstream activities do not drive the
unreasonable risk. The public will have another opportunity to provide comments during the
comment period of the proposed risk management rule.

Section 4.2 - Baseline scenario that does not assumes PPE or other mitigation measures in
place

Section 4.2.1 - Support for EPA's intention not to assume PPE or other mitigation
measures are in place

Several non-governmental environmental and health advocacy organizations (0135, 0144, 0141)
supported EPA's decision to no longer rely on the assumption that workers always and properly
use PPE when determining unreasonable risk, agreeing that EPA's baseline for determining risk
to workers should not assume the use of PPE. One advocacy organization (0144) stated that the
initial assumption regarding PPE lacked legal basis, departed from established federal workplace
protection policy and practice, and is contrary to the realities of worker exposure to chemicals.
The advocacy organization stated that EPA's revised policy approach follows the
recommendation of its SACC to base unreasonable risk determinations for workers on measured
or estimated exposure levels in the absence of PPE.

Two advocacy organizations (0135, 0144) discussed the many limitations of PPE, including
EPA's own statements that respirators are often not feasible and may be used only intermittently
by workers even where legally required. The commenters stated their view that the U.S.
Occupational Safety and Health Administration (OSHA) and the U.S. National Institute for
Occupational Safety & Health (NIOSH), too, have acknowledged the limitations of PPE, having
prioritized hazard elimination, substitution, engineering and administrative controls over the use

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of PPE in the hierarchy of controls. An advocacy organization (0135) said that PPE does not
address exposures to workers who are bystanders, as they are not wearing the PPE, and further
stated its view that the use of a respirator cannot be used to determine if exposure is lessened
sufficiently so that unreasonable risk is mitigated, because EPA does not know the baseline for a
particular facility. The same commenter warned that OSHA regulations concerning PPE only
apply when the employer determines that workers are subject to sufficient hazards from chemical
exposure and whenever else the employer decides it is necessary. Therefore, the employer
decides both whether and what hazards exist and whether use of PPE is necessary. One of the
advocacy organizations (0144) also noted the SACC's assessment that EPA's characterization of
unreasonable risk relying on use of PPE is not sufficiently supported by the practical realities of
many workplaces.

Another commenter (0141) said that the NAS reported that the vast majority of workplaces do
not have a respiratory protection program and estimated that roughly 3.3 percent of American
workers are protected by the respiratory protection program issued under OSHA standards. The
commenter concluded that the revised risk determination accurately reflects the risks workers
face.

The advocacy organization (0135) cited TSCA section 6(b)(4)(A), stating that this provision
precludes EPA from considering risk mitigation in its workplace risk determinations. The
advocacy organization claimed that consideration of the use of PPE - or any other mechanism to
mitigate exposure and risk - is a non-risk factor and should thus not be considered in any form as
part of the risk evaluation.

EPA RESPONSE:

EPA appreciates the feedback concerning assumptions on the use of PPE in the TCE risk
evaluation and the unreasonable risk determination therein, general input regarding PPE, the
interaction of EPA and OSHA regulation, and worker protection.

As stated in the revised unreasonable risk determination for TCE, EPA believes it is appropriate
to evaluate the levels of risk present in scenarios considering applicable OSHA requirements, as
well as scenarios considering industry or sector best practices for industrial hygiene because such
evaluation can help inform potential risk management actions (i.e., by informing EPA's
assessment of the feasibility and efficacy of different risk management options). However, as
commenters note, EPA cannot reasonably assume that all facilities will have adopted these
practices. Additionally, as commenters note, workers not directly engaged in handling the
chemical (such as occupational non-users (ONUs)) are not expected to be provided or wear PPE.
Therefore, EPA is making its determination of unreasonable risk from a baseline scenario that
does not assume compliance with OSHA standards, including any applicable exposure limits or
requirements for use of respiratory protection or other PPE. This reflects EPA's recognition that
unreasonable risk may exist for subpopulations of workers that may be highly exposed because
they are not covered by OSHA standards, or because their employer is out of compliance with
OSHA standards, or because many of OSHA's chemical-specific permissible exposure limits
largely adopted in the 1970's are described by OSHA as being "outdated and inadequate for
ensuring protection of worker health,"6 or because EPA finds unreasonable risk for purposes of

6 As noted on Occupational Safety and Health Administration. Permissible Exposure Limits - Annotated Tables.
Accessed June 13, 2022. https://www.osha.gov/an.notated-peis.

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TSCA notwithstanding existing OSHA requirements. EPA emphasizes that this assumption is for
the purpose of unreasonable risk determination. The use of PPE as a means of addressing
unreasonable risk will be considered during risk management, as appropriate.

Consistent with TSCA section 9(d), EPA is consulting and coordinating TSCA activities with
OSHA, NIOSH, and other relevant federal agencies for the purpose of achieving the maximum
applicability of TSCA while avoiding the imposition of duplicative requirements. Consultation
with other relevant federal agencies is also required during the risk evaluation process under
EPA's implementing regulations at 40 CFR 702.39. EPA will continue to coordinate with
OSHA, NIOSH, and other relevant federal agencies during TSCA risk evaluation and risk
management activities and expects to refine its consultation process as the Agency conducts
additional risk evaluations and risk management rulemakings.

In accordance with TSCA section 26(k), EPA considers reasonably available information when
conducting TSCA section 6 risk evaluations and risk management rules. When undertaking risk
determinations as part of TSCA risk evaluations, EPA cannot assume as a general matter that
workers always or properly use PPE, although it does not question the public comments received
regarding the occupational safety practices often followed by industry respondents. Under TSCA
section 6(a), EPA must apply one or more risk management requirements to the extent necessary
so that a chemical substance no longer presents unreasonable risk. Those requirements may
include restrictions on the manufacture, processing, distribution in commerce, commercial use,
or disposal of a chemical substance.

Section 4.2.2 - Opposition to EPA's intention not to assume PPE or other mitigation
measures are in place

Several commenters expressed opposition to EPA's proposal to not assume the use of PPE when
making its unreasonable risk determination for TCE. For example, some industry trade
organizations (0133, 0136, 0137, 0139, 0142) commented that EPA's decision not to assume the
use of PPE is inconsistent with the requirement to consider COUs under TSCA and contravenes
explicit requirements under TSCA section 26(k) to take into consideration information relating to
a chemical substance or mixture, including hazard and exposure information, under the COUs,
that is reasonably available to the Administrator. One industry trade organization (0142) added
that when EPA rendered unreasonable risk determinations in the TCE risk evaluation and the
other nine initial risk evaluations, EPA's assumption that workplaces comply with the OSHA
regulations was reasonable, appropriate, and driven by data. The industry trade organization
stated its view that such an approach is grounded in the statute and regulations and is supported
by sound science. The commenter also said that EPA should continue to acknowledge and give
credence to what it learns about the physical environments and actual practices in specific sectors
- including worker protection practices - from "reasonably available" information instead of
utilizing assumptions based on speculation regarding what other types of conditions of use of
TCE might exist. Similarly, an industry trade organization (0136) stated that EPA has not
sufficiently supported its refusal to acknowledge the standard use of PPE practices utilized by
industry and regulated by OSHA. A product manufacturer (0143) also disagreed with EPA's
assumption, especially to the extent that it would cause the Agency to identify additional risks of
effects from inhalation and dermal exposures to TCE. The commenter expressed concern that the
identification of risks that are in fact already addressed via PPE will render the revised TCE risk
determination overly conservative.

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An industry trade organization (0133) emphasized that EPA's proposal to determine risk without
considering the effects of current occupational safety standards and PPE practices is not
supported by the record nor reasonably justified by any of the reasons offered by the Agency.
Specifically, the commenter provided its view that EPA cited no data or records to support its
belief concerning the insufficiency of PPE at OSHA regulated facilities. The commenter further
stated that EPA also has not presented any evidence of widespread refusal to comply with OSHA
requirements and stated its view that OSHA does require the use of appropriate PPE where
needed to protect workers from chemical exposures at jobsites. Similarly, another industry trade
organization (0145) stated that EPA's proposed approach would likely leave the public with the
perception that facilities are out of compliance with federal and state safety standards, would
artificially increase the calculated human health risk for particular uses of a chemical, and would
create a false and misleading perception of worker risk. Another industry trade organization
(0139) commented that EPA states that there may be PESS of workers not covered by OSHA
PPE requirements and other OSHA standards, such as self-employed individuals and other
public sector workers, but does not supply any basis in the record for reaching such a conclusion.

An industry trade organization (0145) stated that if EPA believes that certain workplace risks are
not being adequately controlled, then EPA has an obligation under TSCA section 9(a) to consult
with OSHA before superseding OSHA's authority. Any such result from coordination and
consultation with OSHA should also be made publicly available to further transparency, process,
and due diligence. An industry trade organization (0137) stated that, during the first risk
determination for TCE, EPA relied on information such as OSHA requirements, information
supplied in public comments, and safety data sheets, but did not explain why this information
was not valid in the revised risk determination. The commenter also said that in the November
2020 risk evaluation, EPA evaluated conditions of use both with and without protective
measures, which best informs the unreasonable risk determination and the magnitude of potential
risks. The commenter said that, in order for EPA to now determine unreasonable risk and
regulate chemical substances to the extent that the substance no longer presents an unreasonable
risk, it must assume "intentional misuse" as though OSHA has no meaningful legal effect.
According to the commenter, the assumption of misuse contradicts EPA's affirmation in the draft
revised risk determination that it does not question the public comments received on the original
draft risk determination, including those discussing practices of providing PPE to employees and
following established worker protection standards. The commenter said that if EPA does not use
reasonably available information to ground its evaluation of the substance under specific
conditions of use, it is characterizing hazard, instead of risk. Another industry trade organization
(0139) said that EPA has not explained why its prior findings that OSHA requirements will
result in appropriate use of PPE are no longer supported, nor has it explained why its prior
approach to base decisions on unreasonable risk to workers on "high-end exposure estimates" is
no longer a valid method for accounting for uncertainties related to PPE use.

An industry trade organization (0138) stated that there is one TCE manufacturer in the U.S., and
since PPE is known to be used in a manufacturing plant and that information has been clearly
articulated to EPA, EPA must evaluate the COU based on the levels of risk present in the
scenarios considering applicable OSHA requirements and industry best practices.

An industry trade organization (0132) stated that manufacturers are required to follow OSHA
standards and have communicated data to EPA about PPE use. The commenter stated that the

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non-consideration of PPE and engineering controls effectively leaves the risk determination as a
hazard-based standard, which is inconsistent with the risk-based intent of TSCA.

An industry trade organization (0133) stated that EPA's proposal is not transparent about its
plans for implementation of the proposed change in the risk management rule itself and would
request the Agency to develop clear, accurate communication materials to explain EPA's new
approach to PPE to the already OSHA-regulated community. The commenter stated that EPA's
proposal could inadvertently create regulatory confusion and potentially subject companies to
overlapping workplace protection requirements for workplaces that are already subject to OSHA.
The industry trade organization added that such requirements would be costly and either
duplicative of or inconsistent with those that OSHA has already imposed on employers and
employees in OSHA-regulated businesses. Further, the commenter stated its view that EPA's
rationale for no assumption of PPE in risk evaluations is inconsistent with the statutory and
regulatory requirements in the Occupational Safety and Health Act of 1970 (OSH Act) and that
EPA must consult with OSHA and NIOSH to understand whether current worker protection
from exposure to chemicals is consistent with best available science before making any
determinations about the adequacy of OSHA controls.

An industry trade organization (0145) suggested that EPA continue the approach of presenting
both scenarios - TCE use with and without PPE - in its risk determinations, claiming that doing
so would provide the appropriate bounding scenarios for TCE risk exposures in the workplace.
The same commenter stated that waiting until EPA proceeds to the risk management phase to
include the use of OSHA-required PPE and related workplace standards creates a false
impression of risk that lacks transparency, will be misleading to the public, and overestimates the
risk of exposure in workplaces that require workers to follow PPE practices. In addition, it would
create an extra layer of work for EPA and industries to work through the risk management phase,
when adequate protections may already be in place.

Another industry trade coalition (0134) stated that EPA's assumption that PPE is not being used
is incorrect and should not apply to the use of chlorinated materials, including TCE, as feedstock
in chemical synthesis, as all facilities are covered by OSHA and workers in facilities
manufacturing refrigerants are required to and do wear PPE.

EPA RESPONSE:

In the final risk evaluations for the first ten chemical substances, the previous administration
generally assumed that for certain conditions of use workers were always provided, and used,
PPE in a manner that achieved the stated assigned protection factor (APF) for respiratory
protection, or protection factor (PF) for dermal protection. EPA, however, has revisited the
assumption that PPE is always used, and always used properly and effectively, in occupational
settings when making risk determinations for chemical substances and this revised approach is
reflected in the revised unreasonable risk determination for TCE. EPA made this change in
approach due to data on violations of PPE use that indicated assumptions that PPE is always
provided to workers, and worn properly, are not justified.7 EPA understands that there could be
occupational safety protections in place at workplace locations; however, not assuming use of
PPE reflects EPA's recognition that unreasonable risk may exist for subpopulations of workers
that may be highly exposed because they are not covered by OSHA standards, or their employers

7 OSHA Standards and Violation Data https://www.osha.gov/toplOcitedstandards

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are out of compliance with OSHA standards, or because many of OSHA's chemical-specific
permissible exposure limits largely adopted in the 1970's are described by OSHA as being
"outdated and inadequate for ensuring protection of worker health,"8 or because EPA finds
unreasonable risk for purposes of TSCA notwithstanding OSHA requirements. For this reason,
EPA does not identify the absence of PPE to be "intentional misuse" as the commenter asserts.
Continued use of this assumption could result in a risk evaluation that underestimates the risk,
and in turn, a risk management rule that may not provide the needed protections. Under TSCA
section 6(b)(4)(A), EPA is instructed to conduct risk evaluations "to determine whether a
chemical substance presents an unreasonable risk of injury to health or the environment...,
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." TSCA section
3(12) defines "potentially exposed or susceptible subpopulation" as "a group of individuals
within the general population identified by the Administrator 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." That definition provides examples of subpopulations
that may be identified as PESS but provides EPA discretion to identify relevant PESS that will
be evaluated in each risk evaluation. For purposes of the TCE risk evaluation, EPA has identified
workers and ONUs as PESS because these subpopulations experience greater exposure than the
general population. This includes workers and ONUs that may not be covered by OSHA PPE
requirements and other OSHA standards. EPA is not restricted in its identification or evaluation
of workers or ONUs at commercial and industrial facilities that engage in relevant COUs.

EPA's final risk determination is explicit insofar as it does not rely on assumptions regarding the
use of PPE in making the unreasonable risk determination under TSCA section 6, even though
some facilities might be using PPE as one means to reduce worker exposures. In response to the
commenter (0143) expressing concern that the risk determinations will become overly
conservative, EPA emphasizes that information on the use of PPE as a means of mitigating risk
(including public comments received from industry respondents about occupational safety
practices in use) will be considered during the risk management phase, as appropriate. When
conducting the TCE risk evaluation, EPA considered reasonably available information on TCE
hazards and exposures under the conditions of use, including information on current industry
practices, occupational controls and PPE use at commercial and industrial facilities handling
TCE as explained in Section 2.3 of the final risk evaluation. EPA used this information when
developing exposure assessments for TCE. This information is also helpful to inform potential
risk management actions. However, as noted before, EPA cannot reasonably assume that all
facilities will have adopted these practices. Therefore, EPA is making its determination of
unreasonable risk from a baseline scenario that does not assume compliance with OSHA
standards, including any applicable exposure limits or requirements for use of respiratory
protection or other PPE.

The revised unreasonable risk determination for TCE is based on the peer reviewed risk
characterization of the November 2020 TCE Risk Evaluation, which is based on reasonably

8 As noted on Occupational Safety and Health Administration. Permissible Exposure Limits - Annotated Tables.
Accessed June 13, 2022. https://www.osha.gov/an.notated-peis.

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available information pursuant to TSCA section 26(k) and 40 CFR 702.33, and developed in
accordance with TSCA section 26(h) and (i) to make decisions under TSCA section 6 in a
manner consistent with the best available science and weight of scientific evidence. The policy
changes in the revised unreasonable risk determination do not impact the underlying data and
analysis presented in the risk characterization of the risk evaluation, including how the risk
estimates of non-cancer effects to workers from chronic inhalation exposures at the high-end
were calculated and summarized in Table 4-59 of the 2020 Risk Evaluation.

As described in an earlier response, EPA also notes that the assertion that the Agency based its
determination on hazard alone is not correct; the revised unreasonable risk determination is
based on both the hazard of the chemical substance and the exposures or environmental releases,
as described in Sections 3 and 2, respectively, of the November 2020 TCE Risk Evaluation, and
further explained in Sections 5.2 and 5.3 of the revised unreasonable risk determination. The
final risk evaluation already includes exposure analysis with and without PPE. Table 4-59 in the
final risk evaluation presents risk estimates for each COU with and without PPE. EPA has made
no changes to this analysis. Therefore, removing the assumption that workers always and
appropriately wear PPE when making the unreasonable risk determination does not create a need
for new analysis. The revision to the risk determination clarifies that EPA does not rely on the
assumed use of PPE when making the risk determination for the whole substance. Overall, 52
conditions of use drive the TCE whole chemical unreasonable risk determination due to risks
identified for human health.

EPA disagrees with those commenters who thought that eliminating the assumed use of PPE for
risk determination purposes would be misleading to the public. EPA explicitly stated in the draft
revised TCE risk determination and accompanying Federal Register Notice that basing the
unreasonable risk determination on the baseline scenario without PPE should not be viewed as an
indication that EPA believes there are no occupational safety protections in place at any location
or that there is widespread non-compliance with applicable OSHA standards. Rather, as
described earlier, it reflects EPA's recognition that unreasonable risk may exist for workers
(which are included in the risk evaluation as a PESS) that may be highly exposed because they
are not covered by OSHA standards, such as self-employed individuals and public sector
workers who are not covered by a State Plan, or because their employer is out of compliance
with OSHA standards, or because many of OSHA's chemical-specific permissible exposure
limits largely adopted in the 1970's are described by OSHA as being "outdated and inadequate
for ensuring protection of worker health,"9 or EPA finds unreasonable risk for purposes of TSCA
notwithstanding OSHA requirements. In some cases, baseline conditions may reflect certain
mitigation measures, such as engineering controls, in instances where exposure estimates are
based on monitoring data at facilities that have engineering controls in place.

Because the requirements and application of TSCA and OSHA regulatory analyses differ, it is
appropriate that EPA conduct risk evaluations and, where it finds unreasonable risk to workers,
develop risk management requirements for chemical substances that OSHA also regulates, and it
is understood that EPA's findings and requirements may sometimes diverge from OSHA's.

9 As noted on Occupational Safety and Health Administration. Permissible Exposure Limits - Annotated Tables.
Accessed June 13, 2022. https://www.osha.gov/an.notated-peis.

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However, it is also appropriate that EPA consider the standards that OSHA has already
developed, so as to limit the compliance burden to employers by aligning management
approaches required by the agencies, where alignment will adequately address unreasonable risk
to workers.

As a general matter, when undertaking risk management actions, EPA will consider occupational
risk mitigation measures that could address unreasonable risk identified by EPA, and for any
such measures included in a proposed or final TSCA risk management rule, EPA intends to
strive for consistency with applicable OSHA requirements and industry best practices, including
appropriate application of the hierarchy of controls, to the extent that applying those measures
would address the identified unreasonable risk, including unreasonable risk to PESS. In response
to the industry commenters who provided their view regarding assumptions in the vapor
degreasing and chemical manufacturing and synthesis industries, EPA appreciates the
information provided and emphasizes that, when undertaking risk management actions, EPA
intends to develop occupational risk mitigation measures to address any unreasonable risks
identified by EPA, especially in cases where current OSHA standards may not apply or be
sufficient to address the unreasonable risk.

EPA identified the conditions of use that drive the unreasonable risk in the risk determination,
and options will be developed during the process of the Agency working on the risk management
rulemaking to address the unreasonable risk presented by the chemical substance. The risk
management rulemaking stage is not when EPA determines which conditions of use drive the
unreasonable risk.

Under TSCA section 9(a), if EPA determines, in the Administrator's discretion, that an
unreasonable risk may be prevented or reduced to a sufficient extent by action taken under a
federal law that is not administered by EPA, EPA must submit a report to the agency
administering that other authority and undertake a statutorily prescribed referral process. EPA
retains the discretion to make this finding in the first instance.

Consistent with TSCA section 9(d), EPA is regularly consulting and coordinating TSCA
activities with OSHA and other relevant federal agencies for the purpose of achieving the
maximum applicability of TSCA while avoiding the imposition of duplicative requirements.
Informed by the mitigation scenarios and information gathered during the risk evaluation and
risk management process, the Agency might propose rules that require risk management
practices that may be already common practice in many or most facilities. Adopting clear,
comprehensive regulatory standards will foster compliance across all facilities (ensuring a level
playing field) and assure protections for all affected workers, especially in cases where current
OSHA standards may not apply or be sufficient to address the unreasonable risk. EPA
appreciates the suggestion to formalize a consultation process with OSHA, as well request for
transparency regarding such consultations. EPA will continue to coordinate with OSHA and
other relevant federal agencies during TSCA risk evaluation and risk management activities and
expects to refine its consultation process as the Agency conducts additional risk evaluations and
risk management rulemakings. The results of any consultation with OSHA, as well as EPA's
rationale for proposed risk management requirements, including consideration of the OSHA
hierarchy of controls, will be reflected in the proposed rule to address the unreasonable risk

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Response to Public Comments Received

presented by TCE. The public will have an opportunity to comment on the proposed regulatory
action, and EPA will consider such public comments and any additional information before
finalizing the rulemaking.

Section 4.2.3 - OSHA requirements and industry best practices

An industry trade organization (0133) provided several suggestions for how EPA could address
the protection of workers as a PESS including: considering other ways to address concerns about
the population of workers not covered by OSHA standards, developing risk evaluations that do
not assume that PPE is either always or never used in the workplace, working with OSHA during
the scoping phase and discussing improved enforcement of OSHA requirements, considering the
European approach to COUs for the workplace, and more.

EPA RESPONSE:

For purposes of making the TSCA unreasonable risk determination, it is inappropriate to assume
as a general matter that industry best practices are consistently and always properly applied or
that all facilities have adopted these practices. Once EPA has determined that a chemical
substance presents an unreasonable risk, EPA is required to address the identified unreasonable
risk through rulemaking. EPA intends to consider current best workplace practices as it develops
TSCA section 6(a) risk management action to address the unreasonable risk determined in the
TCE risk evaluation, for instance to help inform EPA's assessment of the feasibility and efficacy
of different risk management options. Information on the best workplace practices could also
include information from other countries, such as the European approach mentioned by the
commenters.

As a general matter, when undertaking risk management actions, EPA intends to strive for
consistency with applicable OSHA requirements and industry best practices, including
appropriate application for the hierarchy of controls, to the extent that the requirements, controls,
and practices eliminate the identified unreasonable risks. Informed by the mitigation scenarios
and information gathered during the risk evaluation and risk management process, the Agency
might propose rules requiring risk management practices that may be already common practice
in many or most facilities. Adopting clear, comprehensive regulatory standards will foster
compliance across all facilities (ensuring a level playing field) and assure protections for all
affected workers. EPA will undertake a separate public notice and comment period as part of the
TSCA section 6(a) risk management rulemaking for TCE and will consider public comments and
any additional information before finalizing the rulemaking. Consistent with TSCA section 9(d),
EPA is consulting and coordinating TSCA activities with OSHA and other relevant federal
agencies for the purpose of achieving the maximum applicability of TSCA while avoiding the
imposition of duplicative requirements. Consultation with other relevant federal agencies is also
required during the risk evaluation process under EPA's implementing regulations at 40 CFR
702.39.

As required by TSCA, when conducting risk evaluations, EPA identifies relevant PESS, and
Section 2.3.3 of the TCE Risk Evaluation describes workers and occupational non-users,
including male and female workers of reproductive age as PESS. Notwithstanding the analysis
done for TCE, EPA acknowledges the suggestions by several commenters to identify workers as

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a PESS for future risk evaluations and encourages the commenters to submit chemical-specific
comments on PESS to assist during future risk evaluations' comment periods.

Section 4.2.4 - Other comments regarding determination of unreasonable risk not
assuming PPE or other mitigations measures are in place

An advocacy organization (0135) stated that, while EPA determined that it would be
inappropriate to include the assumption of PPE use for determining whether there is an
unreasonable risk, the Agency stated that it would consider the use of PPE in the risk evaluation
to help inform risk management decision. The organization stated that they view this as an
unsupportable approach. The commenter stated that TSCA prohibits EPA from considering costs
or other nonrisk factors in its risk evaluations. The commenter said that in addition to the fact
that risk management is not part of the risk assessment paradigm, for EPA to include risk
mitigation factors in the risk determination would improperly conflate risk management in TSCA
section 6(a) with the risk determination of TSCA section 6(b). Also, for the Agency to
incorporate certain risk mitigation actions into its risk evaluation and determination would
conflict with the TSCA section 26 requirement that EPA use the best available science. The
commenter concluded that EPA should not consider selected facilities' practices or regulatory
requirements to determine worker risk and should recognize the limitations of using such
information for risk management, as the degree of efficacy can vary depending on the facility.
Similarly, an advocacy organization (0144) cautioned EPA against treating PPE as a best
practice in selecting risk management options.

An industry trade organization (0132) said there will likely be a delay of years between when the
Agency publishes the final risk evaluation and when the Agency publishes the final risk
management actions that take into account PPE. The commenter expressed concern for the
workplace and the potential confusion the final risk determination could cause in this interim
period. The commenter suggested that EPA incorporate a table for industrial and commercial
uses that identifies whether there is an unreasonable risk without PPE and with known PPE,
which would facilitate the submission of more robust and targeted comments during risk
management, and effectively communicate the risk to stakeholders.

An industry trade organization (0137) stated that in the November 2020 risk evaluation, EPA did
not identify employees not covered by OSHA requirements as a PESS in the final risk evaluation
for TCE. The commenter said that such persons, however, are also unlikely to be exposed to the
neat substances or to the substances at elevated concentrations and are therefore not reasonably
foreseen. Though EPA seeks to ensure it addresses unreasonable risk in all occupational
conditions of use, it must first evaluate risk presented to this category of employees under the
intended, known, or reasonably foreseen conditions of use.

The commenter also stated that EPA does not explain how the proposal will be consistent with
the requirement under TSCA section 9(d) that EPA must avoid the duplication of Federal action
against unreasonable risk. The commenter stated that, though EPA states that it intends to consult
and coordinate with OSHA, EPA also assumes that because current OSHA standards do not
extend to all workplaces, regulating the substances under TSCA section 6(a) will appropriately
address unreasonable risk in all occupational settings. However, as the commenter stated, EPA
should also consider that not all workers employed in regulated facilities are regulated by TSCA.
Further, the commenter stated that EPA should evaluate unreasonable risks to workers not

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covered by OSHA standards and consider necessary protections for this category of workers
separately.

An industry trade organization (0138) said that if EPA indeed believes it is appropriate to
evaluate the levels of risk present in the scenarios considering applicable OSHA requirements
and industry or sector best practices in its risk evaluations that serve as the basis for the risk
determination and the risk management rules, it must revise the TCE Risk Evaluation. The
commenter stated that EPA should use different assumptions for estimating worker exposures for
certain COUs being evaluated, such as the manufacture of TCE and its use in the production of
other chemicals (i.e., refrigerants), which they describe as occuring in closed system process
units.

An advocacy organization (0135) expressed support for EPA's proposal to discard the
assumptions of existing worker protection, including use of PPE during risk determinations.
However, the commenter took issue with EPA's statement in the revised risk determination that
in some risk evaluations, levels of risks to workers may be evaluated with and without OSHA
requirements and industry best practices scenarios that are clearly articulated to the Agency. The
advocacy organization stated its view that EPA should not use worker mitigation
characterizations and scenarios during risk evaluation, EPA should also recognize that there are
limitations to such information during risk management.

EPA RESPONSE:

EPA believes it is appropriate to evaluate the levels of risk present in scenarios considering
applicable OSHA requirements, as well as scenarios considering industry or sector best practices
for industrial hygiene because such evaluation can help inform potential risk management
actions (i.e., by informing EPA's assessment of the feasibility and efficacy of different risk
management options). However, as commenters note, for purposes of making the TSCA
unreasonable risk determination, it is inappropriate to assume as a general matter that industry
best practices are consistently and always properly applied or that all facilities have adopted
these practices. Once EPA has determined that a chemical substance presents an unreasonable
risk, EPA is required to address the identified unreasonable risk of injury to health determined in
the TCE risk evaluation and revised risk determination, including unreasonable risk driven by
acute and chronic non-cancer and cancer effects. In response to the comment (0137) that EPA
did not identify employees not covered by OSHA requirements as a PESS, EPA notes that in the
November 2020 Risk Evaluation for TCE EPA identified workers and ONUs (including men and
women of reproductive age, and adolescents), among others, as PESS (see Section 2.3.1 and
Table 4-59), regardless of whether the employees would be covered by OSHA requirements.

The final risk evaluation already includes an exposure analysis with and without PPE. Table 4-59
in the final risk evaluation presents risk estimates for each condition of use with and without
PPE. EPA has made no changes to this analysis. Therefore, removing the assumption that
workers always and appropriately wear PPE when making the unreasonable risk determination
does not create a need for new analysis. The finalized revision to the risk determination clarifies
that EPA does not rely on the assumed use of PPE when making the risk determination for the
whole substance (section 5.1). Overall, 52 conditions of use drive the TCE whole chemical
unreasonable risk determination due to risks identified for human health.

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EPA understands that there could be occupational safety protections in place at workplace
locations; however, not assuming use of PPE reflects EPA's recognition that unreasonable risk
may exist for subpopulations of workers that may be highly exposed because they are not
covered by OSHA standards, or their employers are out of compliance with OSHA standards, or
because many of OSHA's chemical-specific permissible exposure limits largely adopted in the
1970's are described by OSHA as being "outdated and inadequate for ensuring protection of
worker health,"10 or because EPA finds unreasonable risk for purposes of TSCA notwithstanding
OSHA requirements. Regarding the commenter's assertion that EPA should consider that not all
industrial facilities are regulated by TSCA, EPA notes that under TSCA sections 6(a)(2) and (5),
EPA has the authority to prohibit or restrict the manufacture, processing, distribution in
commerce, or manner or method of commercial use of a chemical substance or mixture, with the
definition of chemical substance provided in TSCA section 3.

In response to the commenter (0138) that stated EPA should use different assumptions for
estimating worker exposure in particular industries or COUs, EPA emphasizes that the Agency is
not amending the underlying scientific analysis. EPA also views the peer reviewed hazard and
exposure assessments and associated risk characterization as robust and upholding the standards
of best available science and weight of the scientific evidence per TSCA sections 26(h) and (i).
(87 FR 40520 (July 7, 2022)). The policy changes do not impact the characterization of risk
estimates by condition of use (and summarized in Section 4.2 of the final risk evaluation), or the
occupational exposures to workers and ONUs (and summarized in Section 2.3 of the final risk
evaluation), including an explanation of the different exposures between workers and ONUs,
given the different tasks workers perform under each condition of use.

As a general matter, when undertaking risk management actions, EPA intends to strive for
consistency with applicable OSHA requirements and industry best practices, including
appropriate application of the NIOSH hierarchy of controls, to the extent that the requirements,
controls, and practices eliminate the identified unreasonable risk. Informed by the mitigation
scenarios and information gathered during the risk evaluation and risk management process, the
Agency might propose rules requiring risk management practices that may be already common
practice in many or most facilities. Adopting clear, comprehensive regulatory standards will
foster compliance across all facilities (ensuring a level playing field) and assure protections for
all affected workers. Consistent with the statutory requirements of TSCA section 6(a), EPA will
propose risk management action to the extent necessary so that TCE no longer presents an
unreasonable risk. Also, consistent with TSCA section 9(d), EPA is consulting and coordinating
TSCA activities with OSHA, NIOSH, and other relevant federal agencies for the purpose of
achieving the maximum applicability of TSCA while avoiding the imposition of duplicative
requirements. In the proposed rules under TSCA section 6(a), EPA will explain the consultation
and coordination with other appropriate Federal executive departments and agencies, including
OSHA, as required by TSCA section 9(d). EPA will undertake a separate public notice and
comment period as part of the TSCA section 6(a) risk management rulemaking for TCE, and will
consider public comments and any additional information before finalizing the rulemaking.

In response to the commenter's concern (0135) that EPA is incorporating risk management
actions into the risk evaluation, the Agency clarifies that EPA's final risk determination is

10 As noted on Occupational Safety and Health Administration. Permissible Exposure Limits - Annotated Tables.
Accessed June 13, 2022. https://www.osha.gov/an.notated-peis.

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explicit insofar as it does not rely on assumptions regarding the use of PPE in making the
unreasonable risk determination under TSCA section 6, even though some facilities might be
using PPE as one means to reduce worker exposures. As described earlier, the revised
unreasonable risk determination for TCE is based on the peer reviewed risk characterization in
the November 2020 TCE Risk Evaluation, based on reasonably available information pursuant to
TSCA section 26(k) and 40 CFR 702.33, and developed in accordance with TSCA section 26(h)
and (i) to make decisions under TSCA section 6 in a manner consistent with the best available
science and based on the weight of scientific evidence.

Regarding the comment on PPE as a risk management option, EPA notes that information on the
use of PPE as a means of mitigating risk (including public comments received from industry
respondents about occupational safety practices in use) will be considered during the risk
management phase, as appropriate.

Section 4.2.5 - Permissible exposure limits (PELs)

In response to EPA's statement in the draft revision to the TCE risk determination that the
Agency intends to make its unreasonable risk determination from a baseline scenario that does
not assume compliance with OSHA standards, one commenter (0135) discussed OSHA's PELs.
In expressing support for EPA's proposed assumption, the advocacy organization stated that
OSHA itself has noted that many of its PELs are outdated and inadequate for ensuring protection
of worker health.11 The commenter concluded that, therefore, even when a company may be in
compliance with an OSHA requirement, its worker protection program may nevertheless result
in unreasonable risks to workers.

The advocacy organization (0135) also commented that in the TCE risk determination, EPA
incorrectly suggests that compliance with OSHA PELs may protect against unreasonable risks.
The commenter stated its view that this is misleading since, in determining risk under TSCA,
EPA is directed to not consider cost or other nonrisk factors; in contrast, in setting a PEL, OSHA
must consider technological and economic feasibility. In addition, a greater degree of risk is
acceptable under the OSH Act (significant risk) than under TSCA (unreasonable risk). The
commenter concluded that an unreasonable risk under TSCA would not likely be considered a
significant risk under the OSH Act and, therefore, it is not clear how EPA could envision that
compliance with the OSHA standards would consistently protect against unreasonable risks.

EPA RESPONSE:

OSHA's mission is to ensure that employees work in safe and healthful conditions. The OSH Act
establishes requirements that each employer comply with the General Duty Clause of the Act (29
U.S.C. 654(a)), as well as with occupational safety and health standards issued under the Act.
The General Duty Clause of the OSH Act requires employers to keep their workplace free from
recognized hazards that are causing or are likely to cause death or serious physical harm to
employees. The General Duty Clause is cast in general terms, and does not establish specific
requirements like exposure limits, PPE, or other specific protective measures that EPA could
potentially consider when developing its risk evaluations or risk management requirements.
Because the requirements and application of TSCA and OSHA regulatory analyses differ, it is

11 As noted on Occupational Safety and Health Administration. Permissible Exposure Limits - Annotated Tables.
Accessed June 13, 2022. https://www.osha.gov/an.notated-peis.

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appropriate that EPA conduct risk evaluations and, where it finds unreasonable risk to workers,
develop risk management requirements for chemical substances that OSHA also regulates, and it
is understood that EPA's findings and requirements may sometimes diverge from OSHA's. It is
appropriate, however, that EPA consider the chemical standards that OSHA has already
developed, so as to limit the compliance burden to employers by aligning management
approaches required by the agencies, where alignment will adequately address unreasonable risk
to workers.

EPA conducts baseline assessments of risk and makes its determination of unreasonable risk
from a baseline scenario that is not based on an assumption of compliance with OSHA standards,
including any applicable exposure limits or requirements for use of respiratory protection or
other PPE. Making unreasonable risk determinations based on the baseline scenario should not
be viewed as an indication that EPA believes there are no occupational safety protections in
place at any location, or that there is widespread noncompliance with applicable OSHA
standards. Rather, it reflects EPA's recognition that unreasonable risk may exist for
subpopulations of workers that may be highly exposed because they are not covered by OSHA
standards, such as self-employed individuals and public sector workers who are not covered by a
State Plan, or because their employer is out of compliance with OSHA standards, or because
many of OSHA's chemical-specific permissible exposure limits largely adopted in the 1970's are
described by OSHA as being "outdated and inadequate for ensuring protection of worker
health,"12 or because EPA finds unreasonable risk for purposes of TSCA notwithstanding
existing OSHA requirements

As a general matter, when undertaking risk management actions, EPA intends to strive for
consistency with applicable OSHA requirements and industry best practices, including
appropriate application of the NIOSH hierarchy of controls, to the extent that the requirements,
controls, and practices address the identified unreasonable risks according to TSCA section 6(a).

Section 4.2.6 - Other comments on OSHA requirements or best practices

An advocacy group (0132) discussed how OSHA and NIOSH manage chemical risks using the
"hierarchy of controls." The advocacy group also stated that some commenters incorrectly stated
that EPA's risk management approach under TSCA is undermining OSHA's worker protection
responsibilities.

An industry trade coalition (0134) stated that the chemical synthesis of refrigerants occurs in a
completely closed system where the chlorinated feedstock material is completely consumed.
There is very little exposure, and PPE and emission controls have been in place for years. The
commenter stated that the industry has an exemplary safety record. The commenter discussed
EPA's statement that OSHA rules date back to the 1970s; the commenter reasoned that if OSHA
standards need be updated, OSHA should be asked to update its work as it relates to these
specific compounds.

A product manufacturer (0143) stated that industrial hygiene monitoring is performed
periodically to verify the facility's engineering controls and workplace practices in place are
effective in controlling worker exposure. The commenter said that industrial hygiene sampling

12 As noted on Occupational Safety and Health Administration. Permissible Exposure Limits - Annotated Tables.
Accessed June 13, 2022. https://www.osha.gov/an.notated-peis.

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are well below OSHA PELs, which has allowed the company to mitigate risks of TCE usage in
its operations.

EPA RESPONSE:

Consistent with TSCA section 9(d), EPA is consulting and coordinating TSCA activities with
OSHA and other relevant federal agencies for the purpose of achieving the maximum
applicability of TSCA while avoiding the imposition of duplicative requirements. Consultation
with other relevant federal agencies is also required during the risk evaluation process under
EPA's implementing regulations at 40 CFR 702.39.

When undertaking unreasonable risk determinations as part of TSCA risk evaluations, EPA does
not believe it is appropriate to assume as a general matter that an applicable OSHA requirement
or industry practice related to PPE use is consistently and always properly applied. Mitigation
scenarios included in the EPA risk evaluation (e.g., scenarios considering use of various PPE)
likely represent what is happening already in some facilities. However, the Agency cannot
assume that all facilities have adopted these practices for the purposes of making the TSCA risk
determination. EPA appreciates the information provided by the product manufacturer (0143),
and it will be considered during risk management.

EPA encourages the commenters to submit specific comments about worker protection
measures, including engineering controls and administrative controls, during the future public
comment period for the forthcoming notice of proposed rulemaking for risk management of
TCE. As part of that rulemaking, EPA will consider reasonably available information on worker
protection measures, including information provided by regulated industries.

Section 5 - Unreasonable risk determination

An advocacy organization (0135) stated its view that EPA should not treat workers differently
than the general population when making an unreasonable risk determination for TCE under
TSCA section 6(b)(4), because such differential treatment is based on nonrisk factors and is thus
prohibited under TSCA section 6(b)(4). Specifically, the advocacy organization stated that in the
risk evaluation for TCE, EPA identified unreasonable risks for cancer from chronic inhalation
and dermal exposure to TCE to workers and ONUs, and the Agency's determinations of
unreasonable risk were based on different cancer benchmarks depending on the subpopulation.
The commenter stated that EPA's bifurcated approach to workers vs. everyone else for cancer
risks is illogical, inconsistent, and unsupported by TSCA. The advocacy organization further
stated that workers often face higher risks than the general population, making a less protective
standard particularly unjustified.

The advocacy organization (0135) further commented that, in the final unreasonable risk
determination for TCE, EPA should identify risks from fetal cardiac malformations for the
conditions of use EPA evaluated as the drivers for the whole chemical unreasonable risk. The
commenter urged that doing so is necessary to fulfill EPA's obligation to rely on the best
available science. The advocacy organization explained that fetal cardiac malformations is the
effect identified in the 2011 TCE IRIS assessment as the critical effect of greatest concern for
both acute and chronic non-cancer risks. The commenter noted that the IRIS assessment went
through extensive peer review and is relied upon across EPA, and EPA's Science Advisory

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Board supported the use of the fetal cardiac malformations as the critical effect in setting the
TCE IRIS reference values.

A trade association (0140) commented that in determining the endpoint, reviews by the SACC
and NASEM do not support the use of the developmental toxicity endpoint as a basis for risk
determination. The trade association noted that the NASEM committee report concluded that the
lack of a documented process in systematic review elements greatly defrays confidence in the
fetal cardiac endpoint.

EPA RESPONSE:

EPA evaluates exposures to workers, occupational non-users, consumer users, and bystanders
using reasonably available monitoring and modeling data for exposures to TCE as required under
TSCA section 6(b). Certain assumptions about exposure are taken into account when considering
what constitutes an unreasonable risk presented to the general population and subpopulations
(e.g., workers). A consideration of the exposure circumstances for workers compared to those of
the general population illustrates that it is appropriate to consider a range of benchmarks to
inform risk management approaches. For example, in 2017 when EPA's Office of Water updated
the Human Health Benchmarks for Pesticides, the benchmark for a "theoretical upper-bound
excess lifetime cancer risk" from pesticides in drinking water was identified as 1 in 1,000,000 to
1 in 10,000 over a lifetime of exposure.13 Similarly, EPA's approach under the Clean Air Act to
evaluate residual risk and to develop standards is a two-step approach that "includes a
presumptive limit on maximum individual lifetime [cancer] risk (MIR) of approximately 1 in 10
thousand" and consideration of whether emissions standards provide an ample margin of safety
to protect public health "in consideration of all health information, including the number of
persons at risk levels higher than approximately 1 in 1 million, as well as other relevant factors"
(54 FR 38044, 38045, September 14, 1989).

The cancer risk estimates in the TCE risk evaluation represent the incremental increase in
probability of an individual in an exposed population developing cancer over a lifetime
following exposure to TCE. As such, EPA calculated cancer risk estimates from TCE exposure
for workers and occupational non-users under an 8-hour time weighted average (TWA) and a
lifetime average daily concentration (LADC). The calculation of the cancer risk (i.e., the analysis
of the cancer dose response data) is a scientific analysis. It is typical practice at EPA to calculate
a range of cancer risks from lxlO"4 to lxlO"6. However, the benchmark used in risk management
is a policy choice that considers the scientific analysis. As such, the benchmark value for risk
management of cancer findings is not a bright line and appropriately EPA has discretion. Though
EPA has the discretion to make an unreasonable risk determination for any chemical substance
based on other benchmarks as appropriate (such as lxlO"6 depending on the subpopulation
exposed), lxlO"4 was consistently applied as the benchmark for the cancer risk to individuals in
industrial and commercial workplaces for TCE. The lxlO"4 benchmark for cancer risk to workers
is consistent with the NIOSH cancer guidance for occupational exposures from 2017. Further
information related to this is in section 5.2.3 of the final revised risk determination and section
5.1.1.2 of the November 2020 TCE Risk Evaluation.

13 EPA. Human Health Benchmarks for Pesticides: Updated 2017 Technical Document (pp.5). (EPA 822-R -17 -
001). Washington, DC: U.S. Environmental Protection Agency, Office of Water. January 2017.
https://www.epa. gov/sites/production/files/2015-10/dociimcnts/hh-bcnchmarkstechdoc.pdD.

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In response to the commenters providing their views regarding endpoints that were considered in
the risk evaluation and used for the purposes of risk determination (0135, 0140), in each risk
evaluation under TSCA, EPA determines whether a chemical substance presents an unreasonable
risk of injury to health or the environment under the conditions of use. EPA makes the
unreasonable risk determination without the consideration of costs or other non-risk factors. In
making the unreasonable risk determination, EPA considers relevant risk-related 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 potentially exposed or susceptible subpopulation
or PESS); the severity of hazard (including the nature of the hazard, the irreversibility of the
hazard); and uncertainties. EPA also takes into consideration the Agency's confidence in the data
used in the risk estimate. This includes an evaluation of the strengths, limitations, and
uncertainties associated with the information used to inform the risk estimate and the risk
characterization. This approach is in keeping with EPA's obligation under TSCA section 26(h) to
base its decisions on the best available science, and the Agency's final rule, Procedures for
Chemical Risk Evaluation Under the Amended Toxic Substances Control Act (82 FR 33726,

July 20, 2017).

As described earlier, EPA disagrees with the characterization of the peer review by the trade
association commenter (0140). In the review of studies for the basis of the CHD endpoint, the
SACC members had differences in opinion on the suitability of the evidence. Additional detail
regarding the summary of SACC comments on the peer review can be found in the TCE 2020
Response to Comment.14 There was not a consensus viewpoint from the SACC, and EPA has
appropriately included the CHD studies. In response to the commenter stating that EPA should
use the CHD endpoint as the basis for the risk determination (0135), considering the evidence
and varied opinions concerning the validity and relevance of the CHD database, EPA included
text throughout the 2020 Risk Evaluation acknowledging the uncertainties associated with this
endpoint (Appendix F.l, Section 3.2.4.1.6, Section 3.2.5.3.1, Section 3.2.5.1.6, and Section
3.2.6.1). The 2020 Risk Evaluation explains the various biological factors that may lead to
increased susceptibility to CHDs (e.g., maternal age) and classifies CHDs as a PESS
consideration, and the associated POD and risk estimates are included in the RE in consideration
of PESS groups. EPA has accounted for CHD effects in risk characterization. EPA also notes
that 40 CFR 702.43(a)(1) states that "EPA will: (1) Integrate the hazard and exposure
assessments into quantitative and/or qualitative estimates of risk for the identified populations
(including any potentially exposed or susceptible subpopulation(s)) ...." And "(5) Describe the
weight of the scientific evidence for the identified hazards and exposures."

14 Summary of External Peer Review and Public Comments and Disposition for Trichloroethylene (TCE) Response
to Support Risk Evaluation of Trichloroethylene (TCE), November 2020, EPA-HO-OPPT-20.1.9-0500-01.1.4.

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Section 6 - Conditions of use that drive the unreasonable risk determination
Section 6.1 - Processing

An industry trade coalition (0134) commented that the use of chlorinated chemicals, including
TCE, as feedstock in closed systems to produce fluorinated substances is important and stands
apart from the direct applications and use of these substances as solvents or process aids and
should thus be treated differently. The commenter added that these feedstock materials, including
TCE, are critical to compliance with the American Innovation and Manufacturing Act of 2020
(the AIM Act). The commenter provided some examples of critical uses of products made from
feedstock substances, including TCE, such as in semiconductor and other electronics
applications, as well as defense, medical products, foam insulation and fire protection, and heat
pumps.

EPA RESPONSE:

EPA appreciates the comment (0134) highlighting the overlap of upcoming TSCA section 6(a)
risk management rule for TCE with EPA's actions under the American Innovation and
Manufacturing Act of 2020. EPA will consider this context during the development the
upcoming proposed risk management rule, which will be available for public comment. EPA will
undertake a separate public notice and comment period as part of the TSCA section 6(a) risk
management rulemaking for TCE and will consider public comments and any additional
information before finalizing the rulemaking.

Section 6.2 - Industrial and commercial use

An industry trade organization (0145) commented that research on use of TCE in the automotive
sector indicates that thousands of articles and replacement parts may have been manufactured in
the presence of TCE and, as a result, may contain small amounts of the chemical, bound up in
the article, or have residues and impurities associated with TCE. The commenter stated that TCE
is used in the auto manufacturing process in cleaning and lubricants and may also be present in
adhesives and coatings in auto components. The industry trade organization stated that where
substitutes may exist, the uncertainty created by EPA's focus on a number of solvents has
hindered the testing and selection of a substitute, as industry is concerned about the possibility of
a regrettable substitution, and requested that EPA provide some certainty regarding substitutes so
that identifying TCE substitutes would be a more viable option for any ongoing uses.

A product manufacturer (0143) expressed concern that any rule designed to limit or prohibit the
use of TCE in open top vapor degreasing would adversely affect the commenter's manufacture
of products that are critical components of medical instruments, including implantable medical
devices. The commenter stated that such impacts would affect the supply chain of these devices
and consequently the availability and quality of precision medical devices. The product
manufacturer stated that it had previously submitted comments to the Agency's TCE docket to
describe the commenter's operations and the challenges associated with the identification and
use of replacement solvents and/or degreasing technology. The commenter attached its most
recent submittal, dated November 17, 2021, to its submission, describing it as an up-to-date
summary of technical and economic factors relevant to the commenter's review of potential
replacements. The product manufacturer stated that, to the extent that EPA would regulate TCE

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in the future, EPA should consider granting a critical use exemption for TCE in the production of
medical devices under TSCA section 6(g).

EPA RESPONSE:

EPA appreciates the information provided by each of the commenters (0145 and 0143) regarding
their particular use of TCE. As suggested by several commenters, EPA will be considering the
information in the development of the risk management rule. EPA's consideration of the
information received will be explained in the proposed rulemaking under TSCA section 6(a) and
EPA will consider public comments and any additional information before finalizing the
rulemaking. EPA also notes that the unreasonable risk determination does not consider costs or
other nonrisk factors; EPA intends to consider information regarding potential consequences on
manufacture of products and supply chains during risk management, consistent with TSCA
section 6. EPA appreciates the comment (0143) requesting that EPA take into consideration
critical use exemptions for specific conditions of use of a chemical under TSCA section 6(g) and
also appreciates the information provided by the commenter requesting a TSCA section 6(g)
exemption. This information is helpful to inform risk management action on TCE. Additionally,
under TSCA section 6(c)(2)(C), in deciding whether to prohibit or restrict in a manner that
substantially prevents a specific condition of use of a chemical substance or mixture, and in
setting an appropriate transition period for such action, EPA must consider, to the extent
practicable, whether technically and economically feasible alternatives that benefit human health
or the environment will be reasonably available as a substitute when the proposed prohibition or
other restriction takes effect. The public will have an opportunity to comment on the proposed
regulatory action, and EPA will consider such public comments and any additional information
and the proposed regulatory action before finalizing the rulemaking.

As stated in the revised unreasonable risk determination for TCE, while not appropriate as the
basis for the unreasonable risk determination, EPA believes it is appropriate to evaluate the
levels of risk present in scenarios considering applicable OSHA requirements, as well as
scenarios considering industry or sector best practices for industrial hygiene because such
evaluation can help inform potential risk management actions (i.e., by informing EPA's
assessment of the feasibility and efficacy of different risk management options). EPA encourages
the commenters to submit specific comments about worker protection measures, including
engineering controls and administrative controls, during the future public comment period for the
forthcoming TCE risk management rule. As part of that rulemaking, EPA will consider
reasonably available information on worker protection measures, including information provided
by regulated industries.

Section 7 - Comments regarding conditions of use that do not drive the unreasonable risk
determination

An industry trade organization (0142) said that EPA's revised risk determination may lead to
unwarranted impacts on import of manufactured articles containing TCE. For example, the
commenter stated that the November 2020 risk evaluation indicated that consumer use of TCE in
pepper spray does not present an unreasonable risk. The commenter warned that by taking a
whole chemical approach, EPA may influence a public perception that this condition of use
presents an unreasonable risk without any basis in the record. The commenter also stated that the

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whole chemical approach may increase the likelihood that EPA will regulate the use of chemical
substances in articles that were previously deemed to not present an unreasonable risk,
specifically because EPA views TSCA section 6(a) as permitting EPA to regulate upstream
activities in order to address downstream activities driving unreasonable risk even if those
upstream activities do not drive the unreasonable risk.

An industry trade organization (0132) commented that there is no indication in the current
proposal how COUs that do not pose an unreasonable risk will be addressed. The commenter
stated its view that this creates uncertainty in the marketplace and may lead to unnecessary
supply disruptions that could have been avoided. In addition, the industry trade organization
stated that it is not clear how this would impact the preemptive effects of TSCA. The commenter
recommended that the Agency clearly indicate how EPA intends to approach COUs that do not
pose an unreasonable risk throughout the rest of the risk evaluation process.

An advocacy organization (0135) expressed support for EPA's approach, in that the Agency is
not limited to regulating the precise activities that drive unreasonable risk and for example, may
choose to regulate upstream COUs, such as processing and distribution in commerce, to avoid
downstream unreasonable risk drivers, such as consumer use, even if the upstream activities are
not unreasonable risk drivers.

The advocacy organization (0135) recommended that EPA re-evaluate its risk determination for
distribution in commerce considering exposures from spills and leaks, as well as its assumption
that compliance with existing regulations for the transportation of hazardous materials will not
result in an unreasonable risk. The advocacy organization stated its view that spills and leaks can
result in significant exposures and are not infrequent, unpredictable events; thus, EPA should not
have excluded spills and leaks from the risk evaluation. In addition, the commenter stated that
EPA's assumption that compliance with existing regulations for the transportation of hazardous
materials will not result in an unreasonable risk is without rationale. The advocacy organization
recommended that EPA re-evaluate its risk determination for distribution in commerce
considering exposures from spills and leaks and explain its assumption that compliance with
existing regulations for the transportation of hazardous materials will not result in an
unreasonable risk.

EPA RESPONSE:

In response to the commenter (0142), and as a general matter, EPA understands there is strong
public interest in learning how unreasonable risk from TCE will be addressed, including
potential impacts on specific conditions of use, including those that do not drive the
unreasonable risk for TCE. Consistent with the statutory requirements of TSCA section 6(a),
EPA will by rule apply one or more of the risk management options in TSCA section 6(a) to the
extent necessary so that TCE no longer presents an unreasonable risk. EPA expects to focus its
risk management action on the conditions of use that drive the unreasonable risk. However, as
one commenter suggests (0135), it should be noted that, under TSCA section 6(a), EPA is not
limited to regulating the specific activities found to drive unreasonable risk and may select from
among a suite of risk management requirements in section 6(a) related to manufacture (including
import), processing, distribution in commerce, commercial use, and disposal as part of its
regulatory options to address the unreasonable risk. EPA agrees with the commenter that, as a

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general example, EPA may regulate upstream activities (e.g., manufacturing, processing,
distribution in commerce) in order to address downstream activities (e.g., consumer uses) driving
unreasonable risk even if the upstream activities do not drive the unreasonable risk.

Regarding preemption, as described earlier in this document, 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, as long as that COU was evaluated in the final risk evaluation.

With respect to the comment related to distribution in commerce, spills, and leaks (0135), as in
the November 2020 risk evaluation, EPA's final revised risk determination maintains that
distribution in commerce of TCE is the transportation associated with the moving of TCE in
commerce. EPA has determined that unreasonable risk to workers and ONUs is not driven by the
activities associated with this COU, which consists of the actual moving of the chemical in
commerce. The loading and unloading activities are associated with other conditions of use (e.g.,
processing). EPA assumed limited emissions from the actual transportation of chemicals (i.e.,
neither persons nor the environment would be exposed to the chemical in the transportation
container), given the fact that these chemicals are transported according to existing hazardous
materials transportation rules. In the TCE revised unreasonable risk determination, EPA
recognizes that, due to the practical realities of how chemicals are transported and the fact that
the condition of use is limited to the movement of the chemical in commerce, exposures to
workers are expected to be minimal. Spills and leaks generally were not included within the
scope of the first 10 TSCA risk evaluation, including for TCE.

Based on the limited emissions from the transportation of chemicals, EPA has determined that
distribution in commerce of TCE does not drive the unreasonable risk determination for TCE.

Section 8 - Comments regarding EPA's withdrawal of the associated orders

An industry trade organization (0145) requested that EPA not withdraw the order for the TCE
COUs that were found not to present an unreasonable risk under the November 2020 risk
evaluation. This commenter requested that EPA not withdraw the existing associated orders to
avoid regulatory issues in states which promulgate risk management rules before EPA finalizes
their federal rule and create preemption concerns over state and federal requirements. The
industry trade organization requested that EPA keep the associated orders in place until a second
round of risk evaluations for the ten Work Plan chemicals have been completed to provide
additional certainty throughout the process and until new risk management rules are in place.

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Trichloroethylene (TCE); Revision to Toxic Substances Control Act (TSCA) Risk Determination

Response to Public Comments Received

EPA RESPONSE:

EPA is issuing a final revised unreasonable risk determination for the TCE risk evaluation after
consideration of the public comments received on the draft. For purposes of TSCA section 6(i),
EPA is making a risk determination on TCE as a whole chemical. Under the revised approach,
the "whole chemical" risk determination for TCE supersedes the no unreasonable risk
determinations for TCE that were premised on a condition of use-specific approach to
determining unreasonable risk and also contains an order withdrawing the TSCA section 6(i)(l)
order in Section 5.4.1 of the November 2020 TCE Risk Evaluation. Consistent with the statutory
requirements of TSCA section 6(a), the Agency will propose risk management actions to the
extent necessary to address the unreasonable risk presented by TCE.

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 the chemical substance 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.

Section 9 - Comments on EPA's screening approach to assess risks from air and water
pathways

An industry trade organization (0133) commented that any supplemental analyses for the risk
evaluations that have the potential to influence the risk management rules (including a screening
approach to assess potential risks from the air and water pathways) must be made available for
public comment.

A comment submitted by several state and local government agencies and organizations (0146)
encouraged EPA to consider all exposure pathways for current and future TSCA risk evaluations,
including areas that are, or could be, regulated under other statutes, such as the Clean Air Act,
Clean Water Act, Safe Drinking Water Act, and Resource Conservation and Recovery Act. The
commenter stated its view that EPA's past exclusion of those exposure pathways for the first ten
chemicals was concerning and expressed support for the reevaluation of those findings. The state
government agency encouraged close coordination of TSCA regulatory processes with other
related processes, such as regulation of hazardous air pollutants. The commenter also suggested
that EPA establish an improved screening approach to assess exposures and risks for fenceline
communities and other PESS.

EPA RESPONSE:

As described in the Federal Register Notice, the TCE risk determination has been revised to
reflect announced policy changes to help ensure the public is protected from unreasonable risks
from chemicals in a way that is supported by science and the law. Separately, EPA is conducting
a screening approach to assess risks from the air and water pathways for several of the first 10
chemicals, including TCE. In January 2022, EPA released the TSCA Screening Level Approach
for Assessing Ambient Air and Water Exposures to Fenceline Communities for public comment

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Trichloroethylene (TCE); Revision to Toxic Substances Control Act (TSCA) Risk Determination

Response to Public Comments Received

and peer review; in March 2022, EPA held a public virtual meeting of the Science Advisory
Committee on Chemicals (SACC) to peer review the approach. EPA presented Version 1.0 of a
screening level methodology for assessing potential air and water pathway chemical exposures to
fenceline communities. Along with presenting this methodology, EPA also presented results of
applying the screening methodology (case studies) to 1-brompropane (air pathway), n-
methylpyrrolidone (water pathway), and methylene chloride (air and water pathways). The
proposed screening level methodology went through a public comment period and peer review
(by the SACC) for comments on the proposed methodology as well as recommended revisions or
improvements to the methodology. The SACC delivered its report in May 2022. Following
public comment and peer review, EPA is reviewing comments, recommendations, and
improvements; and modifying the fenceline methodology, as appropriate. EPA expects to
describe its findings regarding the chemical-specific application of this screening-level approach
in the forthcoming proposed TSCA section 6(a) risk management rule for TCE.

EPA notes that the Agency engages in intra-agency review on TSCA risk evaluations, as well as
coordination within EPA to promote the type of coordination the commenter describes. EPA also
notes the opportunities for public engagement throughout the risk evaluation process and
appreciates the comments from state government agencies and others received to date.

Section 10 - Other comments related to the draft revision of the risk determination

Previously submitted comments

A union (0141) requested that EPA incorporate by reference their comments on the HBCD and
methylene chloride revised risk determinations into this docket.

EPA RESPONSE

EPA has considered the commenter's previously submitted comments on the draft revised risk
determinations for HBCD and methylene chloride that were incorporated into its comments on
the TCE draft revised risk determination, and has responded in this document to the general
themes raised by the commenter therein.

Risk Management

An industry trade organization (0155) requested that EPA identify a de minimis level for TCE
below which EPA has no reasonable basis to conclude that there is an unreasonable risk and
recommended that EPA establish a de minimis level for chemicals in articles and mixtures based
on a reasonable potential for exposure. The commenter stated that EPA has recently recognized
the practicality of de minimis thresholds in its "Long-Chain Perfluoroalkyl Carboxylate and
Perfluoroalkyl Sulfonate Chemical Substances; Significant New Use Rule; Supplemental
Proposal" and urged that a standard default de minimis of 0.1% would allow EPA to focus on
major sources and would allow for more effective use of the automotive industry's long-term
investment in its internal International Material Data System. The commenter said that EPA
could also use a data driven approach to establish higher threshold levels if appropriate.

EPA RESPONSE

EPA will consider relevant information in the development of the risk management rule,
including the suggestion (0155) for identifying a de minimis level (though EPA notes that the

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Trichloroethylene (TCE); Revision to Toxic Substances Control Act (TSCA) Risk Determination

Response to Public Comments Received

commenter incorrectly implies that EPA proposed a de minimis threshold in the cited
supplemental proposed Significant New Use Rule). EPA will undertake a separate public notice
and comment period as part of the proposed TSCA section 6(a) risk management rulemaking for
TCE and will consider public comments and any additional information before finalizing the
rulemaking.

Other

A comment submitted by several state and local government agencies and organizations (0146)
commented that many state and local governments are working actively to protect human health
and the environment through toxic chemical policies and regulations; voluntary business
assistance programs; disposal, cleanup and recycling programs; and other pollution prevention
and toxics reduction activities. The commenter expressed appreciation for EPA's work under
TSCA, since strong implementation of TSCA has the potential to support these state and local
programs. The commenter requested that EPA proactively expand its TSCA consultations with
technical staff at state and local governments, particularly those with active toxics reduction,
pollution prevention, and safer alternatives programs and those that have already executed rules
to protect their local communities from chemical risks.

An industry trade organization (0136) expressed support for the goal of implementing TSCA to
eliminate unreasonable human health risks, while at the same time preserving the use of essential
chemistries and products that are important to the U.S. economy. The commenter encouraged
EPA to work with stakeholders to ensure consistent, proper, and successful implementation of
TSCA, specifically in these precedent-setting risk determination revisions.

The comment submitted by several state and local government agencies and organizations (0146)
provided the following recommendations for the TSCA risk evaluation and risk management
processes:

•	Establish a process that expands EPA's required federalism consultations to create a more
meaningful and substantive dialogue with state, local and Tribal governments on its
TSCA risk evaluations. EPA should directly consult with state and local governments
early in the risk evaluation process to ensure its scoping for risk evaluation casts a broad
net and is comprehensive in considering all specific and local uses, hazards, exposures,
and PESS.

•	All sources of exposure must be considered, including sources from products (including
articles), the workplace, manufacturing and processing facilities, recycling and disposal,
and legacy sources. EPA should evaluate cumulative and aggregate exposures to
individuals and communities across multiple pathways, such as air, water, food, and
dermal contact, in work and living settings rather than considering each pathway in
isolation.

•	Risk assessment and risk management rules must fully consider, address, and eliminate
impacts on key at-risk or PESS.

•	EPA cannot fully evaluate safety and should not make determinations of no unreasonable
risk when there is a lack of chemical use, exposure, human health, or eco-toxicological
data. When gaps exist, EPA must fully utilize its TSCA authorities to fill data gaps.

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Trichloroethylene (TCE); Revision to Toxic Substances Control Act (TSCA) Risk Determination

Response to Public Comments Received

•	Risk management regulations that could preempt existing state or local statutes and
regulations should be executed with extreme caution if they are not equally protective in
effect and scope.

•	Create systems to support shifts to safer alternatives, prevent use of regrettable substitutes
that are also hazardous, and support small businesses in those transitions through existing
TCSA authority or through seeking additional authority or resources.

•	Disposal and other end-of-life considerations should be fully addressed in each risk
management rule, including occupational safety and impacts from pollution at legacy
disposal sites, manufacturing sites, household hazardous wastes, and wastewater and
storm water discharges.

EPA RESPONSE:

EPA thanks the commenters for their support of ongoing risk evaluation and risk management of
chemical substances under TSCA. EPA appreciates the commenter's recommendations for future
risk evaluations and the forthcoming risk management rules and encourages the commenter to
submit chemical-specific comments during future risk evaluation and rulemaking comment
periods, including on the issues the commenters have raised, such as data gaps, consideration of
PESS, and sources of exposure. The revised unreasonable risk determination for TCE is based on
the peer reviewed risk characterization in the November 2020 Risk Evaluation, based on
reasonably available information pursuant to TSCA section 26(k) and 40 CFR 702.33, and
developed in accordance with TSCA section 26(h) and (i) to make decisions under TSCA section
6 in a manner consistent with the best available science and based on the weight of scientific
evidence. The November 2020 Risk Evaluation included conditions of use in which TCE was
intended, known or reasonably foreseen to be manufactured, processed, distributed in commerce,
used, or disposed of, including disposal-related hazards and exposures to workers and ONUs at
disposal facilities The policy changes described in the Federal Register Notice announcing the
availability of the draft revised risk determination for TCE do not amend or impact the
underlying data and analysis presented in the risk characterization of the November 2020 TCE
Risk Evaluation.

EPA also acknowledges the best practices established by states and industry experts. During
development of the TSCA section 6(a) risk management rulemaking for TCE EPA has engaged
in required consultations such as the federalism consultation as specified in Executive Order
13132 (64 FR 43255, August 10, 1999) and the tribal consultation as specified in Executive
Order 13175 (65 FR 67249, November 9, 2000), to solicit feedback from the perspective of state
and local governments. In addition to the formal consultations, EPA has met directly with state
and local regulators to hear concerns and gain insight on existing regulations, research, and best
practices. Additionally, EPA has engaged in discussions with representatives from different
industries, non-governmental organizations, technical experts, and users of TCE, and welcomes
continued engagement throughout the development of a risk management rulemaking.

With respect to impacts from this revised unreasonable risk determination on risk management
of TCE, EPA will propose a regulatory action with requirements under TSCA section 6(a) to the
extent necessary so that TCE no longer presents unreasonable risk of injury to health, including
unreasonable risk to identified PESS.

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Trichloroethylene (TCE); Revision to Toxic Substances Control Act (TSCA) Risk Determination

Response to Public Comments Received

Section 11 - Comments on potential revisions to other risk determinations for the first ten
chemicals

An advocacy organization stated (0144) that the Agency must make holistic risk determinations
for all of the initial 10 risk evaluations and apply the whole chemical approach to all risk
evaluations moving forward. In other words, EPA should only consider a whole chemical
approach because it accurately profiles the unreasonable risk a chemical may pose to human
health and the environment. An industry trade organization (0136) commented that as EPA
enacts rulemakings for other chemicals in the future, it should revert to evaluating these
substances on an individual COU basis to ensure innovation and production in the chemical
industry and broader economy are not restricted at the state level. The commenter urged EPA to
avoid an approach that could result in the undesired and unintended outcome of imposing high
costs and strain on industry without the intended decrease in risk.

EPA RESPONSE:

EPA appreciates the comment. As EPA explained in the Federal Register Notice announcing the
availability of the draft revised risk determination for TCE, EPA plans to consider the
appropriate approach for each chemical substance risk evaluation on a case-by-case basis, taking
into account considerations relevant to the specific chemical substance in light of the Agency's
obligations under TSCA. EPA emphasizes that throughout the risk evaluation process, EPA must
"determine whether a chemical substance presents an unreasonable risk of injury to health or the
environment, without consideration of costs or other nonrisk factors" (TSCA section 6(b)(4)(A)),
which would include considerations for innovation and the national economy. However, during
the TSCA section 6(a) risk management rulemaking for any chemical found to present
unreasonable risk, EPA does, as part of the requirements under TSCA section 6(c), consider the
reasonably ascertainable economic consequences of the rule, including consideration of the
effect of the rule on the national economy, small business, technological innovation, the
environment, and public health.

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