2024-10999. Di-isodecyl Phthalate (DIDP) and Di-isononyl Phthalate (DINP); Science Advisory Committee on Chemicals (SACC) Peer Review of Draft Documents; Notice of SACC Meeting; Availability; and Request for Comment

ACTION:

Notice.

SUMMARY:

The Environmental Protection Agency (EPA or “Agency”) is announcing the availability of and soliciting public comment on the draft manufacturer-requested risk evaluation for Di-isodecyl Phthalate (DIDP) and the draft physical chemical, fate, and hazard assessments for Di-isononyl Phthalate (DINP) prepared under the Toxic Substances Control Act (TSCA). The draft documents will also be submitted to the Science Advisory Committee on Chemicals (SACC) for peer review. EPA is also announcing that there will be two virtual public meetings of the SACC: On July 23, 2024, for the SACC to consider the scope and clarity of the draft charge questions for the peer review; and on July 30-August 2, 2024, for the SACC to consider the draft documents and public comments for peer review.

DATES:

Virtual Preparatory Public Meeting

Comments: Submit written comments on the scope and clarity of the charge questions on or before noon (12:00 p.m. EDT) on July 19, 2024.

Registration: To request time to present oral comments, you must register by noon (12:00 p.m. EDT) on July 19, 2024. For those not making oral comments, registration will remain open through the end of the meeting on July 19, 2024.

Meeting date: July 23, 2024, 1 p.m. to 4 p.m. (EDT).

Virtual Peer Review Public Meeting

Comments: Submit comments on or before July 19, 2024.

Registration: To request time to present oral comments, you must register by noon, July 26, 2024. For those not making oral comments, registration will remain open through the end of the meeting.

Meeting dates: July 30-August 2, 2024, 10 a.m. to 5 p.m. (EDT).

Special Accommodations

To allow sufficient time for EPA to process your request before the applicable meeting, please submit your requests at least ten business days in advance of the meeting.

See unit III. of SUPPLEMENTARY INFORMATION .

ADDRESSES:

Comments: Submit your comments, identified by docket identification (ID) number EPA-HQ-OPPT-2024-0073, through the Federal eRulemaking Portal at https://www.regulations.gov. Follow the online instructions for submitting comments. Do not submit electronically any information you consider to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Additional instructions on commenting and visiting the docket is available at https://www.epa.gov/​dockets.

Meeting registration: For information and instructions on how to register and access these virtual public meetings, please refer to the SACC website at https://www.epa.gov/​tsca-peer-review. After registering, you will receive the webcast and streaming service meeting links and audio teleconference information.

Special accommodation requests: To request accommodation for a disability, please contact the Designated Federal Official (DFO) listed under FOR FURTHER INFORMATION CONTACT .

FOR FURTHER INFORMATION CONTACT:

SACC peer review: The Designated Federal Official (DFO) is Dr. Alaa Kamel, Mission Support Division (7602M), Office of Program Support, Office of Chemical Safety and Pollution Prevention, Environmental Protection Agency; telephone number: [phone] or SACC main office number: [phone]; email address: [e-mail].

Draft documents: Todd Coleman, Existing Chemicals Risk Management Division (7404M), Office of Pollution Prevention and Toxics, Office of Chemical Safety and Pollution Prevention, Environmental Protection Agency; telephone number: [phone]; email address: [e-mail].

SUPPLEMENTARY INFORMATION:

I. Executive Summary

A. What action is the Agency taking?

EPA is announcing the availability of and soliciting public comment on the draft risk evaluation for DIDP and the draft physical chemical, fate, and hazard assessments for DINP. EPA is also announcing a virtual peer review public meeting on July 30-August 2, 2024, for the SACC to consider and review the draft documents. A virtual preparatory public meeting will be held on July 23, 2024, for the SACC to consider and ask questions regarding the scope and clarity of the draft charge questions. This document provides instructions for accessing the materials, submitting written comments, and registering to provide oral comments and attend the public meetings.

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

EPA established the SACC in 2016 in accordance with the 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 and may be of particular interest to those involved in the manufacture, processing, distribution, and disposal of the subject chemical substance, and/or those interested in the assessment of risks involving chemical substances and mixtures regulated under TSCA (including members of at-risk communities, non-governmental organizations (NGOs), Federal, State, and local officials). Since other entities may also be interested, the Agency has not attempted to describe all the specific entities that may be interested.

D. What should I consider as I submit my comments to EPA?

1. Submitting CBI. Do not submit CBI to EPA through email or https://www.regulations.gov. If you wish to include CBI in your comment, please contact the DFO listed under FOR FURTHER INFORMATION CONTACT to obtain special instructions before submitting that information.

2. Tips for preparing your comments. When preparing and submitting your comments, see https://www.epa.gov/​dockets/​commenting-epa-dockets. See also the instructions in unit III.C.

E. 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 composed 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, and environmental engineering and sustainability). The SACC currently consists of 18 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 prioritized chemical substances and allows chemical manufacturers to request an EPA-conducted risk evaluation of a chemical substance (or category of chemical substances) using the procedures established in 40 CFR 702.37. TSCA also identifies the minimum components EPA must include in all chemical substance risk evaluations. EPA received manufacturer requests to conduct risk evaluations for DIDP and DINP, both as categories of chemical substances, and subsequently granted and initiated risk evaluations for both of them. 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 is EPA evaluating the risks from DIDP and DINP?

On May 24, 2019, EPA received requests to conduct risk evaluations for DIDP and DINP from ExxonMobil Chemical Company, Evonik Corporation, and Teknor Apex, through the American Chemistry Council's High Phthalates Panel (ACC HPP). In December 2019, EPA notified ACC HPP that the Agency had granted their manufacturer requested risk evaluations.

DIDP is a common chemical name for the category of chemical substances that includes the following substances: 1,2-benzenedicarboxylic acid, 1,2-diisodecyl ester (CASRN 26761-40-0) and 1,2-benzenedicarboxylic acid, di-C9-11-branched alkyl esters, C10-rich (CASRN 68515-49-1). Both CASRNs contain mainly C10 dialkyl phthalate esters.

DINP is a common chemical name for the category of chemical substances that includes the following substances: 1,2-benzenedicarboxylic acid, 1,2-isononyl ester (CASRN 28553-12-0) and 1,2-benzenedicarboxylic acid, di-C9-11-branched alkyl esters, C9-rich (CASRN 68515-48-0). Both CASRNs contain mainly C9 dialkyl phthalate esters. Both DIDP and DINP are primarily used as a plasticizer in polyvinyl chloride (PVC) in consumer, commercial, and industrial applications.

DIDP and DINP are both structurally phthalates, and therefore many aspects of physical-chemical (p-chem) properties and exposure (to humans and ecological species) are similar, described further in the draft physical chemical and fate assessments for both chemical substances. Because of the similar exposure and physical chemical properties of DIDP and DINP, EPA is developing these individual risk evaluations in parallel, and similarly the SACC peer review of the methods and novel analyses for the draft risk evaluations will occur concurrently. Both DIDP and DINP have extremely low water solubility and will be preferentially sorbed into sediments, soils, and suspended solids in surface water and wastewater. Both are expected to be persistent in anaerobic environments. Under indoor settings, DIDP and DINP are expected to partition to airborne particles and are expected to have extended lifetime compared to outdoor settings.

For both DIDP and DINP, liver and developmental toxicity are indicated as the most sensitive and robust non-cancer hazards. However, these two phthalates differ in several important respects regarding their human health hazard profiles. For DIDP, the developmental toxicity is not characterized by androgen insufficiency, and data are insufficient to determine the carcinogenicity. For DINP, developmental toxicity results in androgen insufficiency (phthalate syndrome), and the effects on the liver include cancer. Therefore, because of these hazard differences, EPA is requesting peer review on the draft hazard assessment of DINP ahead of issuing the risk evaluation of DINP.

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

EPA is submitting the draft risk evaluation of DIDP, draft physical chemical, fate, and hazard assessments of DINP, and associated supporting documents to the SACC for peer review, along with the public comments received. The draft risk evaluation for DIDP includes analyses of physical chemical properties, the fate and transport in the environment, exposure to workers, consumers and general population including potentially exposed or susceptible subpopulations (PESS), 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 assessments of DINP includes analyses of physical chemical properties, the fate and transport in the environment, environmental hazard for terrestrial and aquatic species, human health non-cancer hazards, and human health cancer hazards.

EPA is not developing charge questions for all aspects of the draft documents but is instead focusing its charge to the SACC on specific scientific areas that need peer review. 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 ( e.g., systematic review, consumer exposure model (CEM), American Meteorological Society (AMS)/EPA Regulatory Model (AERMOD), point source calculator (PSC), etc.). Also, EPA is not soliciting comments on uses of these phthalates that are outside the scope of TSCA ( e.g., personal care products, cosmetics, food contact materials, medical devices); those uses will be addressed as appropriate within the cumulative risk assessment.

As a result of the similarities in conditions of use, chemical properties, and data availability between DIDP and DINP, the methods and approaches used to assess DIDP apply to DINP. Nonetheless, these two chemicals differ most in their human health hazard profiles and therefore SACC is requested to review these novel analyses for DINP. Any relevant recommendations from this SACC review on DIDP will be also considered in the development of the final risk evaluations for both DIDP and DINP. By taking the DIDP risk evaluation and DINP hazard assessments to peer review in this manner, EPA will obtain the necessary independent review and advice for the DINP risk evaluation.

EPA continues to work on risk evaluations of additional high-priority substance phthalates, in addition to the cumulative risk assessment (CRA) for the phthalates. The subsequent five individual risk evaluations and the CRA are not part of this peer review but will be brought to the SACC for peer review at a future date.

III. Public Meeting of the SACC

A. What is the purpose of the virtual peer review public meeting(s)?

EPA is planning two virtual public meetings: (1) A preparatory public meeting for the SACC to consider and ask questions regarding the scope and clarity of the draft charge questions; and (2) a public meeting for the SACC to consider and review the draft documents. These public meetings are part of the SACC peer review of the Agency's methods and novel analyses for the draft evaluations of the risks from the phthalates DIDP and DINP to inform risk management decisions under TSCA. EPA expects to ask the SACC to consider and review this DIDP draft risk evaluation and DINP assessments. The agenda for these meetings will be posted in the docket and the SACC website.

To participate in these virtual public meetings, you must register online to receive the webcast and streaming service meeting links and audio teleconference information for each meeting. Online registration will be available beginning approximately one month prior to the meeting, and remain open through the end of the meeting. To make oral comments during one of these meetings, follow the instructions in unit III.C.

Recommendations from this SACC review and public comments will be considered in the development of the final risk evaluation for DIDP and DINP. The Agency will be seeking SACC review of its data analyses and methodologies relevant to human health hazard and exposure analyses that have not been previously peer reviewed.

B. How can I access the documents?

The manufacturer-requested draft risk evaluation for DIDP, draft assessments for DINP, and related documents, including background documents, related supporting materials, and draft charge questions, are available in the docket. As additional background materials become available, EPA will include those additional background materials ( e.g., SACC members and consultants participating in this meeting and the meeting agenda) in the docket and through links on the SACC website at https://www.epa.gov/​tsca-peer-review.

After the public meeting, the SACC will prepare the meeting minutes and a final report document summarizing its recommendations to the EPA, which will also be available in the docket and through the SACC website.

C. How can I provide comments?

To ensure proper receipt of comments, it is imperative that you identify docket ID No. EPA-HQ-OPPT-2024-0073 in the subject line on the first page of your comments and follow the instructions in this document.

1. Written comments. Submit written comments by the deadlines set in the DATES section of this document and as described in the ADDRESSES section of this document.

2. Oral comments. To request time to present oral comments during one of the virtual public meetings, you must register online by the deadlines set in the DATES section of this document. Oral comments during the virtual public meetings are limited to 5 minutes. In addition, each speaker should submit a written copy of their oral comments and any supporting materials ( e.g., presentation slides) to the DFO prior to the meetings for distribution to the SACC.

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

Dated: May 15, 2024.

Michal Freedhoff,

Assistant Administrator, Office of Chemical Safety and Pollution Prevention.