[Federal Register Volume 89, Number 56 (Thursday, March 21, 2024)]
[Notices]
[Pages 20201-20203]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-06049]


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ENVIRONMENTAL PROTECTION AGENCY

[EPA-HQ-OPPT-2024-0114; FRL-11809-01-OCSPP]


1,1-Dichloroethane (1,1-DCA); 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 or the Agency) is 
seeking nominations of scientific and technical experts to review the 
draft risk evaluation for 1,1-dichloroethane (1,1-DCA) conducted under 
the Toxic Substances Control Act (TSCA). The Agency will release the 
draft risk evaluation for public review and comment in spring of 2024 
through a separate Federal Register document and subsequently will 
provide the selected peer reviewers with the draft risk evaluation for 
letter peer review in the summer of 2024.

DATES: Submit your nominations on or before April 11, 2024.

ADDRESSES: Submit your nomination via email to [email protected]. 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: The Peer Review Leader is Alie Muneer, 
Mission Support Division (7602M), Office of Program Support, Office of 
Chemical Safety and Pollution Prevention, Environmental Protection 
Agency; telephone number: (202) 564-6369 or call the main office at 
(202) 564-8450; email address: [email protected].

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 experts for 
the letter peer review of the draft risk evaluation for 1,1-DCA. EPA 
will be soliciting comments from the experts on the approach and 
methodologies utilized in the draft risk evaluation. This document 
provides instructions for submitting such nominations for EPA to 
consider for the planned letter peer review. EPA will publish a 
separate document in the Federal Register in spring 2024 to announce 
the availability of the draft risk evaluation and solicit public 
comments. Comments received and the draft risk evaluation materials 
will be provided to the letter peer reviewers in the summer of 2024.

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 addressed 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 and mixtures 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 of Peer Reviewers

A. Why is EPA seeking nominations for peer reviewers?

    EPA is requesting nominations from the public and stakeholder 
communities for scientific and technical experts who can serve as 
prospective candidates for letter peer reviews. This is part of a 
broader process for developing a pool of candidates. Interested persons 
or organizations can nominate qualified individuals by following the 
instructions provided in this document. Individuals are also welcome to 
self-nominate.
    Those who are selected from the pool of prospective candidates will 
be asked to review the draft risk evaluation for 1,1-DCA and provide 
their individual comments to EPA.

B. What expertise is sought for this letter peer review?

    Individuals nominated for this letter peer review should have 
expertise in one or more of the following areas:
    1. Environmental hazard assessment expertise, specifically with 
experience in analog selection, predictive modeling, and uncertainty 
analysis.
    2. Human health toxicology with expertise in cancer modes of 
action, reproductive toxicity and derivation of points of departure 
(PODs) and dose-response values using limited toxicity datasets.
    3. Human health toxicology with expertise in the use of read across 
methodology, the identification of analog, and the application of read 
across software, such as OECD QSAR Toolbox, GenRA and CompTox.
    4. Human exposure assessment experience, especially for industrial 
hygiene and occupational inhalation exposures, susceptible life stages 
and subpopulations to environmental contaminants.
    5. Expertise in using EPA databases for contaminant concentration 
estimates in ambient air and/or surface water and sediments.
    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 via 
email to the email identified in ADDRESSES. Each nomination should 
include the following: Contact

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information for the person or entity making the nomination; name, 
affiliation, and contact information for the nominee; and the 
disciplinary and specific areas of expertise of the nominee.

D. Will peer 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 the 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 peer 
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 peer 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 letter peer 
reviews. 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 peer 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 approximately 10-12 peer reviewers for this 
letter peer review.
    EPA plans to make a list of candidates under consideration as 
prospective peer reviewers for this letter peer review available for 
public comment by summer of 2024. The list will be available in the 
docket at https://www.regulations.gov (docket ID number EPA-HQ-OPPT-
2024-0114).

III. Letter Peer Review

A. What is the purpose of this Letter Peer Review?

    The focus of this letter peer review is to review the approach and 
methodologies utilized in the draft risk evaluation for 1,1-DCA. 
Feedback from this review will be considered in the development of the 
final 1,1-DCA risk evaluation.
    EPA intends to announce in spring 2024 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. The draft risk evaluation and public comments will be 
provided to the letter peer reviewers in the summer of 2024.

B. Why did EPA develop these documents?

    1,1-DCA was designated in December 2019 as a High-Priority 
Substance for risk evaluation under TSCA (84 FR 71924, December 30, 
2019 (FRL-10003-15), and is currently in the risk evaluation process. 
In August 2020, the Agency released the final scope document outlining 
the hazards, exposures, conditions of use, and the potentially exposed 
or susceptible subpopulations the agency expects to consider in its 
risk evaluation (85 FR 55281, September 4, 2020 (FRL-10013-90).
    1,1-DCA is a volatile, colorless, oily liquid with a chloroform-
like odor, which is primarily used in organic chemical manufacturing. 
1,1-DCA is manufactured and used primarily in industrial applications, 
such as a reactant for the manufacture of other chemicals or as a 
laboratory chemical. The reported total production volume (PV) of 1,1-
DCA in 2015 and 2020 was between 100 million and 1 billion pounds. EPA 
assumes that a high percentage of the PV is used for processing as a 
reactive intermediate, and a small percentage of the PV is used for 
commercial use as a laboratory chemical. EPA did not identify any 
consumer uses of 1,1-DCA.
    The major exposure pathway to 1,1-DCA is through releases to air. 
1,1-DCA is estimated to have high water solubility and once it is 
released into water, it remains primarily in the water column. EPA, 
therefore, also assessed relevant surface water and land exposure 
pathways. EPA relied on databases reporting multi-year 1,1-DCA releases 
to ambient air, surface water, and disposal to land, such as the Toxic 
Release Inventory (TRI), the National Emissions Inventory (NEI) and 
Discharge Monitoring Reports (DMR), among others, to conduct major 
portions of its exposure analysis. Due to limited empirical data for 
human health and portions of the environmental hazard assessments, EPA 
relied on read-across approaches to supplement 1,1-DCA data to develop 
hazard values.
    EPA plans to submit the draft risk evaluation of 1,1-DCA and 
associated supporting documents for letter peer review in the summer of 
2024. The draft risk evaluation includes analyses of physical-chemical 
properties; the fate and transport in the environment; exposure to 
workers, and general population including potentially exposed or 
susceptible subpopulations; releases to the environment; environmental 
hazard and risk characterization for terrestrial and aquatic species; 
and human health hazard and risk characterization for workers and the 
general population.
    EPA is focusing its letter peer review charge on specific 
scientific areas and analyses and is not developing charge questions 
for all aspects of the risk evaluation. Many of the methods and 
analyses used in these evaluations are not novel and have been reviewed 
in the development of the tools used in various agency work products or 
in previous TSCA assessments.
    EPA is requesting feedback on novel approaches, unique exposure 
analyses and other calculations, approaches and results associated with 
the human health and environmental hazard endpoints. Specifically, EPA 
is seeking comment on the issues below:
     For human health hazard, EPA has limited empirical 
toxicity data available for 1,1-DCA. EPA has employed an approach for 
developing the human health hazard values through the utilization of 
read across to supplement the 1,1-DCA database using information from 
the identified analog, 1,2-dichloroethane (1,2-DCA). EPA is seeking 
review of the approach for

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developing the human health hazard values including the selection and 
application of a read across using 1,2-DCA as an analog; on the 
benchmark response (BMR) for the hazard value chosen for the human 
health hazard value used for the acute, short-term and chronic exposure 
durations; and on the weight of scientific evidence and confidence for 
specific hazard endpoints of central nervous system (CNS) depression/
sedation, degeneration/necrosis of olfactory mucosa and decreased sperm 
concentration.
     For environmental hazard for aquatic and benthic 
organisms, EPA has limited empirical toxicity data available for 1,1-
DCA and has employed an approach for developing the environmental 
hazard values through read across using a method for analog selection. 
EPA used 1,2-DCA and 1,1,2-trichloroethane as analogs to read across 
environmental hazard to 1,1-DCA. EPA is seeking comment on the use of 
analog data in combination with 1,1-DCA data to estimate risk to 
aquatic vertebrates and invertebrates, including benthic invertebrates.
     EPA obtained primary inhalation exposure monitoring data 
for 1,1-DCA for the occupational exposure scenario (OES) of Manufacture 
through a test order and prioritized the use of occupational inhalation 
monitoring data for the intended condition of use and other appropriate 
exposure scenarios (e.g., Processing as a Reactant and Laboratory Use 
OESs). EPA is seeking comment on the use of inhalation exposure 
monitoring data for these analogous exposure scenarios.
     EPA used surrogate chlorinated solvent inhalation 
monitoring data to estimate occupational exposures for the OES where 
there was a lack of inhalation monitoring data and applied a vapor 
pressure correction factor to account for vapor pressure differences 
between the surrogate chemical and 1,1-DCA. EPA is seeking comments on 
the use of surrogate data to estimate occupational exposures.
     For dermal exposures, EPA lacked specific 1,1-DCA dermal 
absorption data. Therefore, EPA used the Dermal Exposure to Volatile 
Liquids Model (DEVL) and applied the model to all OES; however, values 
for fraction absorbed and weight fraction of the chemical can differ 
among OES. EPA is seeking comments on the application of DEVL to all 
OESs and is seeking methods to better differentiate the dermal exposure 
potential and the resulting risks between OES.

C. How can I access the documents submitted for this letter peer 
review?

    EPA is planning to release the draft risk evaluation for 1,1-DCA, 
all background documents and related supporting materials in the spring 
of 2024. At that time, EPA will publish a separate document in the 
Federal Register to announce the availability of and solicit public 
comment on the materials and provide instructions for submitting 
comments. The materials will be available in the docket and through the 
TSCA Scientific Peer Review Committees website. In addition, as 
additional background materials become available (e.g., list of experts 
participating in this letter peer review), EPA will include the 
additional materials in the docket and through the website.

    Dated: March 14, 2024.
Michal Freedhoff,
Assistant Administrator, Office of Chemical Safety and Pollution 
Prevention.
[FR Doc. 2024-06049 Filed 3-20-24; 8:45 am]
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