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###### Environmental Protection Agency

          - [EPA-HQ-OPPT-2024-0551; FRL-12418-01-OCSPP]

# AGENCY:

Environmental Protection Agency (EPA).

# ACTION:

Notice.

# SUMMARY:

                        The Environmental Protection Agency (EPA or Agency) is seeking public nominations of scientific and technical experts that EPA can consider for service as                         *ad hoc*                         reviewers assisting the Science Advisory Committee on Chemicals (SACC) with the peer review of the Agency's technical support documents for benzyl butyl phthalate (BBP), dibutyl phthalate (DBP), di(2-ethylhexyl) phthalate (DEHP), diisobutyl phthalate (DIBP), and dicyclohexyl phthalate (DCHP) and the cross-phthalate technical support documents for human health benchmark dose (BMD) analysis, cancer analysis, and cumulative risk analysis. To facilitate nominations, this document provides information about the SACC, the intended topic for the planned peer review, the expertise sought for this peer review, instructions for submitting nominations to EPA, and the Agency's plan for selecting the                         *ad hoc*                         reviewers for this peer review. EPA is planning to convene a virtual public meeting of the SACC in the spring of 2025 to review the technical support documents.                    

# DATES:

Submit your nominations on or before January 2, 2025.

# ADDRESSES:

                        Submit your nominations to                         *SACC@epa.gov.*

# FOR FURTHER INFORMATION CONTACT:

                        The Designated Federal Official (DFO) for the SACC is 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 or call the SACC main office at (202) 564-8450; email address:                         *kamel.alaa@epa.gov.*

# SUPPLEMENTARY INFORMATION:

## I. General Information

### A. What action is the Agency taking?

                    The Agency is seeking public nominations of scientific and technical experts that EPA can consider for service as                     *ad hoc*                     reviewers assisting the SACC with the peer review of the Agency's technical support documents for the evaluation of the risks from BBP, DBP, DEHP, DIBP and DCHP to inform risk management decisions under TSCA. EPA is planning to hold a virtual public meeting in the spring of 2025 for the SACC to consider and review technical support documents. At that time, EPA will solicit comments from the SACC on the critical inputs and novel approaches for a variety of charge questions related to individual, draft chemical risk evaluations and the draft cumulative risk analysis.                

                    To facilitate nominations, this document provides information about the SACC, the intended topic for the planned peer review, the expertise sought for this peer review, instructions for submitting nominations to EPA, and the Agency's plan for selecting the                     *ad hoc*                     reviewers for this peer review.                

### 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.*

                    The SACC was established by EPA in 2016 in accordance with TSCA, 15 U.S.C. 2625(o), to provide independent advice and expert consultation with respect to the scientific and technical aspects of issues relating to the implementation of TSCA. The SACC operates in accordance with the Federal Advisory Committee Act (FACA), 5 U.S.C. 10, and supports activities under TSCA, 15 U.S.C. 2601*et seq.,*                     the Pollution Prevention Act (PPA), 42 U.S.C. 13101*et seq.,*                     and other applicable statutes.                

### C. Does this action apply to me?

                    This action is directed to the public in general. This action may, however, be of particular 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. Members of at-risk communities, non-                          ( print page 95783)                        governmental organizations (NGOs) (particularly those with an interest in protecting health for at-risk communities), and Federal, State and local officials may also be interested. Since other entities may also be interested, the Agency has not attempted to describe all the specific entities to which this action may apply.                

### D. How can I stay informed about SACC activities?

                    You may subscribe to the following listserv for alerts regarding this and other SACC-related activities:                     *https://public.govdelivery.com/​accounts/​USAEPAOPPT/​subscriber/​new?​topic_​id=​USAEPAOPPT_​101.*

## II. Background

### A. What is the purpose of the SACC?

                    The SACC provides independent advice and recommendations to the EPA on the scientific and technical aspects of risk assessments, methodologies, and pollution prevention measures and approaches for chemicals regulated under TSCA. The SACC is comprised of experts in toxicology; environmental risk assessment; exposure assessment; and related sciences (                    *e.g.,*                     synthetic biology, pharmacology, biotechnology, nanotechnology, biochemistry, biostatistics, physiologically based pharmacokinetic (PBPK) modeling, computational toxicology, epidemiology, environmental fate, environmental engineering and sustainability). The SACC currently consists of 20 members. When needed, the committee will be assisted by                     *ad hoc*                     reviewers with specific expertise in the topics under consideration.                

### B. Why is EPA conducting these risk evaluations?

                    TSCA requires EPA to conduct risk evaluations on high-priority chemical substances and identifies the minimum components EPA must include in all chemical substance risk evaluations. The purpose of conducting risk evaluations is to determine whether a chemical substance presents an unreasonable risk to human health or the environment under the Conditions of Use (COUs). These evaluations include assessing unreasonable risks to relevant potentially exposed or susceptible subpopulations. As part of this process, EPA: (1) Integrates hazard and exposure assessments using the best available science that is reasonably available to assure decisions are based on the weight of the scientific evidence, and (2) Conducts peer review for risk evaluation approaches that have not been previously peer reviewed. For more information about the three stages of EPA's process for ensuring the safety of existing chemicals (                    *i.e.,*                     prioritization, risk evaluation, and risk management), go to                     *https://www.epa.gov/​assessing-and-managing-chemicals-under-tsca/​how-epa-evaluates-safety-existing-chemicals.*

### C. Why did EPA develop these documents?

EPA designated the following chemicals as High-Priority Substances for risk evaluation under TSCA in December 2019: BBP (Butyl Benzyl Phthalate, CASRN 85-68-7), DBP (Dibutyl Phthalate, CASRN 84-74-2), DEHP (Di(2-ethylhexyl) Phthalate, CASRN 117-81-7), DIBP (Diisobutyl Phthalate, CASRN 84-69-5), and DCHP (Dicyclohexyl Phthalate, CASRN 84-61-7). For these chemicals, EPA published draft and final scope documents in April and August 2020, respectively and, is currently in the risk evaluation process. The scope documents outlined the hazards, exposures, conditions of use, and the potentially exposed or susceptible subpopulations the Agency expected to consider in its risk evaluations. Although there are some differences in conditions of use and exposures, these chemical substances are primarily used as plasticizers in polyvinyl chloride (PVC) products and in adhesives, sealants, paints, coatings, rubbers, and other applications. Because of the significant similarities in exposure and physical chemical properties of these phthalates, EPA is developing these risk evaluations and the cumulative risk assessment in parallel. DIDP and DINP were reviewed previously by the SACC (July 30-August 1, 2024); the draft risk evaluations for BBP, DBP, DEHP, DIBP and DCHP are incorporating many of the SACC recommendations from this previous peer review.

EPA is soliciting comments from the SACC on a variety of charge questions related to the data, methods, models, approaches for these draft chemical risk evaluations, including the supporting draft cumulative risk assessment analysis. 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 focusing peer review on the critical inputs and novel approaches.

The draft risk evaluations for BBP, DBP, DEHP, DIBP and DCHP include analyses of physical chemical properties, fate and transport in the environment, exposure to workers, consumers and general population including potentially exposed 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, consumers, and the general population. The draft cumulative risk assessment analysis was developed based on the Proposed Approach for Cumulative Risk Assessment under TSCA including recommendations from the May 2023 SACC review. Specifically, the cumulative risk assessment analysis technical support document calculates relative potency factors for phthalate syndrome for each of the six chemical substances based on a pooled dataset for assessing fetal testicular testosterone health endpoint and estimates cumulative non-attributable exposures from NHANES urinary biomonitoring data.  

### D. What is the topic of the planned SACC peer review?

EPA anticipates soliciting peer review from the SACC on the following draft documents:
    - Physical and chemical and environmental fate technical support documents for BBP, DBP, DEHP, DIBP and DCHP.
    - Ecological hazard technical support documents for BBP, DBP, DEHP, DIBP and DCHP.
    - Non-cancer human health hazard technical support documents for BBP, DBP, DEHP, DIBP and DCHP.
    - Cancer technical support document (a single document that includes BBP, DBP, DEHP, DIBP and DCHP).
    - Environmental Releases and Occupational Exposure technical support documents for BBP, DBP, DEHP, DIBP and DCHP.
    - Environmental and General Population Exposures to Environmental Releases technical support documents for BBP, DBP, DEHP, DIBP and DCHP.
    - Consumer and Indoor Air Exposure technical support documents for BBP, DBP, DEHP, DIBP and DCHP.
    - Meta-analysis and benchmark dose technical support document developed for the draft cumulative risk assessment.
    - Technical support document for the Cumulative Risk Analysis of Di(2-ethylhexyl) Phthalate (DEHP), Dibutyl Phthalate (DBP), Butyl Benzyl Phthalate (BBP), Diisobutyl Phthalate (DIBP), Dicyclohexyl Phthalate (DCHP), and Diisononyl Phthalate (DINP) under TSCA.
    - Aspects of the risk evaluation for DCHP, including risk characterization and application of the cumulative risk analysis.       ( print page 95784)      

EPA expects to solicit feedback on the following scientific issues:
    -  Physical-chemical properties and environmental fate technical support documents.                      EPA expects to solicit feedback on the data and methods used to characterize physical-chemical properties and environmental fate of BBP, DBP, DEHP, DIBP and DCHP. Of particular importance are the n-octanol/water partition coefficients (K ow ), organic carbon-water partition coefficients (K oc ), n-octanol/air partition coefficients (K oa ), bioaccumulation factors (BAF), and bioconcentration factors (BCF). For DCHP specifically, EPA expects to solicit specific feedback on the weight of the scientific evidence approach to describe the water solubility range for DCHP and the use of a single value as input to exposure models.                
    -  Ecological hazard technical support documents.                      EPA expects to solicit feedback on the data and methods used to characterize ecological hazards of BBP, DBP, DEHP, DIBP and DCHP.                
    -  Non-cancer human health hazard technical support documents.                      EPA expects to solicit feedback on multiple scientific areas including the selection of non-cancer points of departure used to characterize non-cancer risks from acute, intermediate, and chronic durations for BBP, DBP, DEHP, DIBP and DCHP. For DEHP there are additional hazards for which EPA will solicit input; specifically, female reproductive tract, inhalation, and glucose homeostasis/lipid metabolism.                
    -  Cancer hazard technical support document.                      EPA has developed a single document evaluating cancer hazard potential for these phthalates. EPA expects to solicit feedback on the following: draft cancer classifications for DEHP, BBP, and DBP; tumor triad (liver, pancreatic, and testicular tumors) and PPARα mode of action information relevant to DEHP; and the application of Rethinking Carcinogenicity Assessment for Agrochemicals Project (ReCAAP) weight of evidence framework for DCHP and DIBP.                
    -  Meta-analysis and benchmark dose modeling technical support document and the cumulative risk assessment technical support documents.                      EPA expects to solicit input on the methods and data used to calculate background exposure levels from the NHANES data set, derive relative potency factors, index chemical selection, and methods and application of background exposures. The draft risk evaluation of DCHP will contain an example of the application of cumulative risk assessment analysis for an individual chemical. EPA anticipates requesting input on the integration of the cumulative approaches within the individual chemical risk characterization.                
    -  Technical support documents for environmental and general population, consumer and indoor air, and occupational exposures.                      EPA expects to request feedback and guidance on the data and methods used in the draft exposure assessments. Included in this request for input will be issues related to dermal absorption, such as the interpretation of                      in vitro                      and                      in vivo                      studies and the use of flux-based calculations for occupational exposures. Of specific importance are the data and methods used to calculate dermal absorption and exposures in the occupational exposure and the consumer and indoor air exposure technical support documents.                

                    Given the large volume of material across the five HPS phthalates, EPA will be releasing chemical-specific technical support documents in batches ahead of the draft risk evaluations. The formal 60-day public comment period for each chemical risk evaluation will begin when the Agency publishes a notice of availability in the                     **Federal Register**                     and the chemical's full risk evaluation, including the risk characterization and risk determination, are posted to the chemical specific docket. Most immediately, the Agency anticipates that the DCHP risk evaluation, and its associated supporting documents, is expected to be released to the public at the end of December, and a notice of availability will begin the public comment period for the DCHP draft risk evaluation. Over the next several months, EPA expects to release all the technical support documents for BBP, DBP, DEHP, and DIBP into their respective chemical specific dockets as they are available, and their dockets will be open for submission of comments. Nonetheless, these TSDs will be formally available for a 60-day public comment period with the release of each chemical risk evaluation to follow.                  

                    In the first quarter of 2025, OPPT will publish a notice of availability in the                     **Federal Register**                     for the draft charge questions and to begin an additional public comment period in this docket (EPA-HQ-OPPT-2024-0551) specifically for the peer review by the SACC. At that time, all of the risk evaluation documents (                    *e.g.,*                     technical support documents, supplemental files, etc.) relevant to peer review will also be made available in this docket for a targeted peer review. EPA anticipates requesting SACC peer review of the questions pertaining to critical inputs and novel approaches contained in these documents to constitute full peer review of the phthalate risk evaluations. The SACC peer review will be focused on the DCHP risk evaluation and associated supporting documents, and the technical support documents that describe the data and analyses of physical chemistry and fate, hazards, exposures, and releases for BBP, DBP, DEHP, and DIBP.                

In total, EPA anticipates six opportunities for public comment; five dockets and comment periods associated with each chemical (BBP, DBP, DEHP, DIBP and DCHP) and one docket focused on the SACC peer review.

## III. Nominations for ad hoc Reviewers

### A. Why is EPA seeking nominations for ad hoc reviewers?

                    As part of a broader process for developing a pool of candidates for SACC peer reviews, EPA is asking the public and stakeholders for nominations of scientific and technical experts that EPA can consider as prospective candidates for service as                     *ad hoc*                     reviewers assisting the SACC with the peer reviews. 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 invited to attend the public meeting and to participate in the discussion of key issues and assumptions at the meeting. In addition, they will be asked to review and to help finalize the meeting minutes and final report.

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

                    Individuals nominated for this SACC peer review should have expertise in one or more of the following areas: Physical and chemical properties of phthalates including water solubility, bioconcentration and bioaccumulation, analytical chemistry, modeling and field derived data; Ecological hazard identification including general ecological hazard identification and use of read-across and new alternative methods; Environmental releases including methods for modeling and considerations for use of monitoring data; General population exposure including use of screening methods and refinements; Occupational exposure including dermal exposure modeling with consideration of empirical absorption data; Consumer exposure and indoor air exposure including                           ( print page 95785)                        modeling data selection and interpretation and use of monitoring data; Human health toxicology including inhalation hazard, glucose metabolism, liver toxicity, phthalate syndrome, mode of action for cancer and non-cancer, benchmark dose modeling and dose response analysis; Cumulative and mixtures risk assessment for human health including index chemical selection and relative potency factor derivations; Biostatistics including analysis of NHANES biomonitoring data and derivation of occupational exposure limits; Epidemiology related to individual chemicals and phthalate mixtures for use in risk assessments.                

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?

                    Submit your nomination as directed under                     **ADDRESSES**                     by the deadline indicated under                     **DATES**                    . Each nomination should include the following information: 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.                

                    Do not submit confidential business information (CBI) or other sensitive information to EPA through email. If your nomination contains any information that you consider to be CBI or otherwise protected, please contact the DFO listed under                     **FOR FURTHER INFORMATION CONTACT**                     to obtain special instructions before submitting that information.                

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

                    SACC members and                     *ad hoc*                     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 for service on the SACC 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 on the SACC. Selected candidates are required to complete an ethics training prior to conducting their reviews.                

### E. How will EPA select the ad hoc reviewers?

                    The selection of scientists to serve as                     *ad hoc*                     reviewers for the SACC is based on the function of the Committee and the expertise needed to address the Agency's charge to the Committee. No interested scientists shall be ineligible to serve by reason of their membership on any other 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 Committee's reviews, ability to be hired as an EPA Special Government Employee (SGE), 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 on the SACC.                

                    Numerous qualified candidates are often identified for SACC reviews. Therefore, selection decisions involve carefully weighing several 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                     *ad hoc*                     reviewers for the SACC that are received by the deadline listed under                     **DATES**                    . However, the final selection of                     *ad hoc*                     reviewers is a discretionary function of the Agency.                

                    EPA anticipates selecting approximately ten (10)                     *ad hoc*                     reviewers to assist the SACC in their review of the designated topic. EPA plans to make a list of candidates under consideration as prospective                     *ad hoc*                     reviewers for this review available for public comment by the winter of 2025. The list will be available in the docket at                     *https://www.regulations.gov*                     (docket ID No. EPA-HQ-OPPT-2024-0551) and through the SACC website at                     *https://www.epa.gov/​tsca-peer-review.*

*Authority:*15 U.S.C. 2625(o); 5 U.S.C. 10.                

Dated: November 26, 2024.

Michal Freedhoff,

Assistant Administrator, Office of Chemical Safety and Pollution Prevention.

[FR Doc. 2024-28287 Filed 12-2-24; 8:45 am]

BILLING CODE 6560-50-P