[Federal Register Volume 88, Number 188 (Friday, September 29, 2023)]
[Notices]
[Pages 67278-67280]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-21544]


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ENVIRONMENTAL PROTECTION AGENCY

[EPA-HQ-OPPT-2023-0265; FRL-11109-01-OCSPP]


Tris(2-chloroethyl) Phosphate (TCEP); Draft Risk Evaluation under 
the Toxic Substances Control Act (TSCA); Letter Peer Review; Request 
for Nominations of Expert Reviewers

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice.

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SUMMARY: The Environmental Protection Agency (EPA) is seeking public 
nominations of scientific and technical

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experts to review the draft Risk Evaluation for Tris(2-chloroethyl) 
Phosphate (TCEP) conducted under the Toxic Substances Control Act 
(TSCA). The draft risk evaluation will be released for public review 
and comment in December 2023 through a separate Federal Register 
document and subsequently submitted for letter peer review by the 
expert reviewers.

DATES: Nominations should be submitted in time to arrive no later 
October 30, 2023.

ADDRESSES: Submit your nominations to the Peer Review Leader listed 
under FOR FURTHER INFORMATION CONTACT. Do not electronically submit any 
information you consider to be Confidential Business Information (CBI) 
or other information whose public disclosure is restricted by statute. 
If your nomination may contain any such information, please contact the 
Peer Review Leader to obtain special instructions before submitting 
that information.

FOR FURTHER INFORMATION CONTACT: Contact the Peer Review Leader, Dr. 
Alaa Kamel, Mission Support Division (7602M), Office of Program 
Support, Office of Chemical Safety and Pollution Prevention, 
Environmental Protection Agency; telephone number: (202) 564-5336; 
email address: [email protected] or call the main office: (202) 564-
8450.

SUPPLEMENTARY INFORMATION: 

I. General Information

A. What action is the Agency taking?

    The Agency is seeking public nominations of scientific and 
technical experts that the EPA can consider for service as peer 
reviewers for the review of the ``2023 Draft Risk Evaluation for 
Tris(2-chloroethyl) Phosphate (TCEP).'' EPA will be soliciting comments 
from the reviewers on the approach and methodologies utilized in the 
draft 2023 TCEP risk evaluation.
    This document provides instructions for submitting nominations for 
EPA to consider for reviewers. EPA will publish a separate document in 
the Federal Register in December 2023 to announce the availability of 
the draft risk evaluation and solicit public comments.

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

    TSCA section 6(b) requires that EPA conduct risk evaluations on 
existing chemical substances and identifies the minimum components EPA 
must include in all chemical substance risk evaluations (15 U.S.C. 
2605(b)). The risk evaluation must not consider costs or other non-risk 
factors (15 U.S.C. 2605(b)(4)(F)(iii)). The specific risk evaluation 
process is set out in 40 CFR part 702 and summarized on EPA's website 
at https://www.epa.gov/assessing-and-managing-chemicals-under-tsca/risk-evaluations-existing-chemicals-under-tsca.

C. Does this action apply to me?

    This action is directed to the public in general. This action may, 
however, be of interest to those involved in the manufacture, 
processing, distribution, and disposal of chemical substances and 
mixtures, and/or those interested in the assessment of risks involving 
chemical substances regulated under TSCA. Since other entities may also 
be interested, the Agency has not attempted to describe all the 
specific entities that may be affected by this action.

II. Nominations for Peer Reviewers

A. Why is EPA seeking nominations for peer reviewers?

    As part of a broader process for developing a pool of candidates 
for peer reviews, EPA is asking the public and stakeholder communities 
for nominations of scientific and technical experts that EPA can 
consider as prospective candidates to serve as peer reviewers. Any 
interested person or organization may nominate qualified individuals 
for consideration as prospective candidates for this review by 
following the instructions provided in this document. Individuals may 
also self-nominate.
    Those who are selected from the pool of prospective candidates will 
be asked to review the draft risk evaluation for TCEP and to help 
finalize the Letter Review report.

B. What expertise is sought for this peer review?

    Individuals nominated for this peer review, should have expertise 
in one or more of the following areas: environmental fate assessment; 
environmental hazard assessment; human health toxicology with 
experience in cancer mode of action, reproductive toxicology, 
neurotoxicology, and renal toxicology; dose-response modeling; 
physiologically based pharmacokinetic (PBPK) modeling; and human or 
environmental exposure assessment, especially for susceptible life 
stages and subpopulations to environmental contaminants, and experience 
with particle versus gaseous partitioning and air deposition of semi-
volatile organic compounds (SVOCs). Nominees should be scientists who 
have sufficient professional qualifications, including training and 
experience, to be capable of providing expert comments on the 
scientific issues for this review.

C. How do I make a nomination?

    By the deadline indicated under DATES, submit your nomination to 
the Peer Review Leader listed under FOR FURTHER INFORMATION CONTACT. 
Each nomination should include the following: Contact information for 
the person making the nomination; name, affiliation, and contact 
information for the nominee; and the disciplinary and specific areas of 
expertise of the nominee.

D. Will ad hoc reviewers be subjected to an ethics review?

    Peer reviewers are subject to the provisions of the Standards of 
Ethical Conduct for Employees of the Executive Branch at 5 CFR part 
2635, conflict of interest statutes in Title 18 of the United States 
Code and related regulations. In anticipation of this requirement, 
prospective candidates will be asked to submit confidential financial 
information which shall fully disclose, among other financial 
interests, the candidate's employment, stocks and bonds, and where 
applicable, sources of research support. EPA will evaluate the 
candidates' financial disclosure forms to assess whether there are 
financial conflicts of interest, appearance of a loss of impartiality, 
or any prior involvement with the development of the documents under 
consideration (including previous scientific peer review) before the 
candidate is considered further for service.

E. How will EPA select peer reviewers?

    The selection of scientists to serve as peer reviewers is based on 
the expertise needed to address the Agency's charge to the reviewers. 
No interested scientists shall be ineligible to serve by reason of 
their membership on any advisory committee to a federal department or 
agency or their employment by a federal department or agency, except 
EPA. Other factors considered during the selection process include 
availability of the prospective candidate to fully participate in the 
Letter Review, absence of any conflicts of interest or appearance of 
loss of impartiality, independence with respect to the matters under 
review, and lack of bias. Although financial conflicts of interest, the 
appearance of loss of impartiality, lack of independence, and bias may 
result in non-selection, the absence of such concerns does not assure 
that a candidate will be selected to serve as a peer reviewer.
    Numerous qualified candidates are often identified for the review.

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Therefore, selection decisions involve carefully weighing a number of 
factors including the candidates' areas of expertise and professional 
qualifications and achieving an overall balance of different scientific 
perspectives across reviewers. The Agency will consider all nominations 
of prospective candidates for service as peer reviewers that are 
received on or before the date listed in the DATES section of this 
document. However, the final selection of peer reviewers is a 
discretionary function of the Agency. At this time, EPA anticipates 
selecting 10-12 reviewers in the review of the designated topic.
    EPA plans to make a list of candidates under consideration as 
prospective peer reviewers for this review available for public comment 
by late fall of 2023. The list will be available in the docket at 
https://www.regulations.gov (docket ID number EPA-HQ-OPPT-2023-0265).

III. Letter Review

A. What is the purpose of this Letter Review?

    The focus of this Letter Review is to review the approach and 
methodologies utilized in the ``2023 Draft Risk Evaluation for Tris(2-
chloroethyl) Phosphate (TCEP).'' Feedback from this review will be 
considered in the development of the final TCEP risk evaluation.
    EPA intends to announce in December 2023, in the Federal Register, 
the availability of and solicit public comment on the draft risk 
evaluation, at which time EPA will provide instructions for submitting 
public comments for the Agency's and Letter Peer Reviewers' 
consideration.

B. Why did EPA develop these documents?

    TCEP is a High-Priority substance undergoing the TSCA risk 
evaluation process after passage of the Frank R. Lautenberg Chemical 
Safety for the 21st Century Act, which amended TSCA.
    TCEP has been primarily used in paint and coating manufacturing, 
and in polymers used in aerospace equipment and products. In the past 
it has also been used in commercial and consumer products, including 
fabric and textile, products, foam seating, and construction materials. 
TCEP may also be imported in articles intended for consumer use.
    In August 2020, EPA published a final scope document for 20 High-
Priority substances, including TCEP, outlining the hazards, exposures, 
conditions of use, and the potentially exposed or susceptible 
subpopulations the Agency expects to consider in its risk evaluation.
    EPA is submitting the ``2023 Draft Risk Evaluation for Tris(2-
chloroethyl) Phosphate (TCEP)'' and associated supporting documents for 
Letter Peer Review. The Letter Peer Review will include review of the 
analysis of physical chemical properties, the fate of TCEP in the 
environment, releases of TCEP to the environment, environmental hazard 
and risk characterization for terrestrial and aquatic species, and 
human health hazard and risk characterization for workers, consumers, 
and the general population. Specifically, EPA is seeking comment on the 
following issues:
     The list of considerations EPA used to arrive at the human 
health hazard confidence levels and the specific confidence levels 
chosen for individual human health hazard outcome (neurotoxicity, 
reproductive/developmental effects, kidney effects, and cancer) in the 
TCEP risk evaluation.
     Whether the approach used to estimate anaerobic 
degradation in the absence of data is appropriate for assessing 
anaerobic degradation in sediment.
     Use of the model, Web-based Interspecies Correlation 
Estimation (Web-ICE), to predict acute toxicity hazard values for 
aquatic species not represented in the available studies. This is the 
first time EPA has used Web-ICE in a TSCA risk evaluation. These 
predictions were used with available empirical data to create a Species 
Sensitivity Distribution (SSD). The SSD was used to calculate a 
hazardous concentration for 5% of species (HC05). EPA is 
also using a data-driven way of accounting for uncertainty for 
environmental hazard and is soliciting comment on its characterization 
of this uncertainty, specifically its use of the lower bound of the 95% 
confidence interval of the hazardous HC05.
     Human health hazard benchmark dose modeling of animal 
toxicity data for TCEP.
     The list of considerations EPA used to arrive at the human 
health hazard confidence levels and the specific confidence levels 
chosen for individual human health hazard outcomes (neurotoxicity, 
reproductive/developmental effects, kidney effects, and cancer) to 
quantitatively evaluate risk from TCEP.
     Use of several approaches for estimating exposures to 
humans and environmental receptors: (1) The use of Verner 2008 Multi-
compartment model, which was used to assess TCEP exposure to infants 
through human milk for the first time in a TSCA risk evaluation; (2) 
the use of Verner 2008 Multi-compartment model and associated 
uncertainties in extrapolating from the inhalation to oral routes of 
exposure; (3) the use of AERMOD model to estimate air deposition of 
TCEP. EPA has used AERMOD in previous TSCA risk evaluations; however, 
its use in estimating air deposition is novel for TSCA risk 
evaluations.
     Approach for modeling drinking water contamination from 
wells near municipal solid waste landfills, which is a new approach for 
TSCA risk evaluations.

C. How can I access the documents submitted for review to the SACC?

    EPA is planning to release the ``2023 Draft Risk Evaluation for 
Tris(2-chloroethyl) Phosphate (TCEP)'' and all background documents, 
related supporting materials, and draft charge questions in December 
2023. At that time, EPA will publish a separate document in the Federal 
Register to announce the availability of and solicit public comment on 
the draft risk evaluation and provide instructions for submitting 
written comments. These materials will be available in the docket at 
https://www.regulations.gov (docket ID number EPA-HQ-OPPT-2023-0265) 
and through the TSCA Scientific Peer Review Committees website. In 
addition, as additional background materials become available, EPA will 
include those additional background documents (e.g., reviewers 
participating in this letter review) in the docket and through the 
website.
    Authority: 15 U.S.C. 2625(h).

    Dated: September 26, 2023.
Michal Freedhoff,
Assistant Administrator, Office of Chemical Safety and Pollution 
Prevention.
[FR Doc. 2023-21544 Filed 9-28-23; 8:45 am]
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