By Lynn L. Bergeson and Carla N. Hutton
 
On May 16, 2023, the U.S. Government Accountability Office (GAO) released publicly a report on its priority open recommendations for the U.S. Environmental Protection Agency (EPA). GAO’s priority recommendations include three in the area of “assessing and controlling toxic chemicals.” According to GAO, EPA’s ability to protect effectively public health and the environment depends on credible and timely assessments of the risks posed by toxic chemicals, including per- and polyfluoroalkyl substances (PFAS). GAO states that implementing the following three priority recommendations in this area, such as by establishing an ongoing process to assess the resources required to complete successfully Integrated Risk Information System (IRIS) chemical assessments, would improve EPA’s ability to prepare and issue the assessments:

• To develop the timely chemical risk information that EPA needs to conduct its mission effectively, the EPA Administrator should require the Office of Research and Development (ORD) to reevaluate its draft proposed changes to the IRIS assessment process in light of the issues raised in the report and ensure that any revised process periodically assesses the level of resources that should be dedicated to this significant program to meet user needs and maintain a viable IRIS database. According to GAO, as of February 2023, officials from ORD’s Chemical and Pollutant Assessment Division (CPAD) had conducted an analysis of the resources needed to produce chemical assessments, including IRIS assessments and Provisional Peer-Reviewed Toxicity Values. The analysis concluded by noting that CPAD is under-resourced and expects to experience a continued increase in its workload in coming years, thereby worsening the gap between what EPA offices need and what CPAD is able to produce. GAO states that CPAD’s analysis did not identify specific metrics for assessing the effectiveness of EPA’s staff recruitment and retention strategies or whether current resource allocations are helping CPAD meet the targets established in various EPA strategic action plans. GAO will keep the recommendation open until CPAD updates its analysis to include more specific metrics, which will help EPA determine the effectiveness of its recruitment and retention strategies.
   
• To ensure better the credibility of IRIS assessments by enhancing their timeliness and certainty, the EPA Administrator should require ORD to establish a written policy that clearly describes the applicability of the timeframes for each type of IRIS assessment and ensures that the timeframes are realistic and provide greater predictability to stakeholders. According to GAO, as of March 2023, EPA officials were considering ways to provide additional documentation to help stakeholders better understand the timeframes for completing IRIS assessments. GAO “encourage[s] EPA to provide its program offices with documentation of how long it takes to complete each of these different types of assessments to reduce uncertainty for stakeholders with significant interests in IRIS assessments.”
   
• The EPA Administrator should include in ORD’s strategic plan (or subsidiary strategic plans) identification of EPA’s universe of chemical assessment needs; how the IRIS program is being resourced to meet user needs; and specific implementation steps that indicate how IRIS will achieve the plan’s objectives, such as specific metrics to define progress in meeting user needs. GAO states that it will keep this recommendation open until CPAD updates its analysis to include such specific metrics and more information is available for GAO to determine the extent to which EPA management has used CPAD’s analysis to balance its workload with available resources. This would ensure EPA and CPAD can better identify and meet user needs.

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By Lynn L. Bergeson and Carla N. Hutton

The U.S. Environmental Protection Agency (EPA) announced on March 23, 2023, that it 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 “2023 Draft Supplement to the 1,4-Dioxane Risk Evaluation.” 88 Fed. Reg. 17566. EPA states that it will release the draft supplement for public review and comment in June 2023. EPA also plans to submit the draft supplement to the SACC for peer review and is scheduling a four-day virtual public meeting for the SACC to consider and review the draft supplement in September 2023. Nominations are due April 24, 2023.
 
According to EPA, the focus of the four-day virtual public meeting is the SACC peer review of the methodologies that have not been previously peer reviewed and are used in the 2023 1,4-dioxane supplemental risk evaluation. EPA will consider feedback from this review in the development of the final supplement to the 1,4-dioxane risk evaluation. EPA notes that in addition, SACC reviewer feedback may help refine EPA’s methods for conducting release assessments and evaluating general population exposures in risk evaluations of other chemicals under the Toxic Substances Control Act (TSCA).
 
EPA intends to publish a separate document in the Federal Register to announce the availability of and solicit public comment on the draft supplement, at which time EPA will provide instructions for submitting written comments and registering to provide oral comments at the peer review meeting planned for September 2023. EPA also intends to provide a meeting agenda for each day of the meeting, and as needed, may provide updated times for each day in the meeting agenda that will be posted in the docket and on the SACC website.
 
SACC serves as a scientific peer review mechanism of EPA’s Office of Chemical Safety and Pollution Prevention (OCSPP). It provides independent scientific advice and recommendations to EPA on the scientific basis for risk assessments, methodologies, pollution prevention measures, and approaches for chemicals regulated under TSCA.

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By Lynn L. Bergeson and Carla N. Hutton
 
The U.S. Environmental Protection Agency (EPA) has opened registration for the second of its two-part webinar series on EPA’s new standardized process to assess risk and apply mitigation measures, as appropriate, for mixed metal oxides (MMO), including new and modified cathode active materials (CAM). The webinar, which will be held March 30, 2023, will give an in-depth look into the standardized risk assessment approach and present various case scenarios and a decision tree for identifying potential hazards and risks. The kickoff webinar, held in November 2022, provided a broad overview of the approach and answered stakeholder questions. A summary of the first webinar is available in our November 23, 2022, memorandum.
 
Under the Toxic Substances Control Act (TSCA), EPA reviews all new chemical substances before they enter the marketplace to ensure they do not present unreasonable risk to human health or the environment. As reported in our October 11, 2022, memorandum, EPA announced an innovative effort to help make its review of new MMOs, including new and modified CAMs, more efficient. According to EPA, MMOs have many electrical applications in batteries and uses as catalysts, adsorbents, and in ceramics. Notably, MMOs, including CAMs, are a key component in lithium-ion batteries used in electric vehicles, making them a vital part of clean energy sectors.

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By Lynn L. Bergeson and Carla N. Hutton
 
The U.S. Environmental Protection Agency (EPA) announced on February 13, 2023, that it will accept public comments on candidates under consideration for selection as ad hoc reviewers to assist the Science Advisory Committee on Chemicals (SACC) with peer review of two draft documents related to cumulative risk assessment under the Toxic Substances Control Act (TSCA). Biographies of these candidates are available on regulations.gov. If selected, candidates will serve as peer reviewers for two documents, which will be reviewed by the SACC at a public virtual meeting May 8-11, 2023. Comments on the candidates are due February 25, 2023.
 
EPA states that it plans to release the following documents for public comment in late February 2023:

• Draft Proposed Principles of Cumulative Risk Assessment under the Toxic Substances Control Act: According to EPA, this document will describe the fundamental principles of cumulative risk assessment of chemicals and how they may be applied within the regulatory requirements of TSCA to ensure TSCA risk evaluations are based on the best available science and are protective of human health; and
   
• Draft Proposed Approach for Cumulative Risk Assessment of High-Priority Phthalates and a Manufacturer Requested Phthalate under the Toxic Substances Control Act: EPA states that this document will describe its proposed approach for evaluating a subset of high-priority and manufacturer-requested phthalates for cumulative risk to human health under TSCA based on the principles of cumulative risk assessment described in EPA’s draft principles document referenced above.

The SACC serves as a scientific peer review mechanism of EPA’s Office of Chemical Safety and Pollution Prevention (OCSPP). It provides independent scientific advice and recommendations to EPA on the scientific basis for risk assessments, methodologies, pollution prevention measures, and approaches for chemicals regulated under TSCA.

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By Lynn L. Bergeson and Carla N. Hutton
 
The U.S. Environmental Protection Agency (EPA) announced on December 21, 2022, that it seeks public nominations of scientific and technical experts whom EPA can consider for service as ad hoc reviewers assisting the Science Advisory Committee on Chemicals (SACC) with the peer review of two draft documents entitled “Draft Proposed Principles of Cumulative Risk Assessment Under the Toxic Substances Control Act” and “Draft Proposed Approach for Cumulative Risk Assessment of High-Priority Phthalates and a Manufacturer Requested Phthalate Under the Toxic Substance Control Act.” 87 Fed. Reg. 78103. EPA states that it will submit the two draft documents to SACC and release them for public review and comment in late February 2023. EPA will solicit comments from SACC on issues related to chemical grouping for purposes of cumulative risk assessment (CRA), health outcomes related to phthalate syndrome, and possible approaches to developing the cumulative hazard and exposure assessment for high-priority phthalates and a manufacturer-requested phthalate. EPA also announced the scheduling of a four-day virtual public meeting for SACC to consider and review the two draft documents. EPA provides the following chronological listing of the dates for the specific activities:

• January 20, 2023 -- Deadline for submitting all nominations to EPA;
   
• April 24, 2023 -- Deadline for submitting a request for special accommodations to allow EPA time to process the request before the meeting; and
   
• May 8 to 11, 2023, from 10:00 a.m. to approximately 5:30 p.m. (EDT) -- The public virtual meeting will be held via a webcast platform such as “Zoom.gov” and audio teleconference, and you must register to receive the links.

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By Lynn L. Bergeson and Carla N. Hutton
 
The U.S. Environmental Protection Agency (EPA) announced on November 9, 2022, that it awarded $7,770,044 in research grant funding to 11 institutions to develop and evaluate innovative methods and approaches to inform its understanding of the human health risks that may result from exposure to chemical mixtures in the environment. EPA states that toxicology studies have traditionally focused on the effects of single chemicals on human health. Chemicals in the environment are often present as mixtures in the air, water, soil, food, and products in commerce, however, and these chemical mixtures include per- and polyfluoroalkyl substances (PFAS), phthalates, polycyclic aromatic hydrocarbons (PAH), disinfection byproducts (DBP), and other well-characterized mixtures. According to EPA, there is a need to assess the toxicity of chemical mixtures to understand how their combined effects on human health and the environment differ from what is known about individual chemicals. Due to their lower cost and higher throughput, new approach methods (NAM) and use of alternative animal models have emerged as potential approaches to advance the risk assessment of mixtures.
 
To help address this research need, the institutions receiving these grants will conduct research focused on the development, improvement, evaluation, and integration of predictive toxicology methods to evaluate environmental chemical mixtures. The grantees and their project titles include:

• Georgia Institute of Technology, Atlanta, Georgia -- High-Throughput Lung Damage and Inflammation Assessment of Polyaromatic Hydrocarbon Mixtures;
   
• Medical University of South Carolina, Charleston, South Carolina -- Developing an Integrated Framework for Evaluating Toxicity of Real-life Chemical Mixtures;
   
• Purdue University, West Lafayette, Indiana -- Protein Binding Affinity as the Driver for Studying PFAS Mixture Toxicity;
   
• The Research Foundation of CUNY, New York, New York -- Innovative Approach to Assess the Effect of Metal Mixtures from Infant Meconium Associated with Adverse Infant Outcomes by Identifying Methylation Loci in Mothers and Infants;
   
• Texas A&M University, College Station, Texas -- A Tiered Hybrid Experimental-Computational Strategy for Rapid Risk Assessment of Complex Environmental Mixtures Using Novel Analytical and Toxicological Methods;
   
• University at Buffalo, Buffalo, New York -- Assessment of Neurotoxicity of Mixtures of PFAS and Other Neuroactive Organic Pollutants through Integrated in Silico, in Vitro Cellular, and in Vivo Models;
   
• University of Georgia Research Foundation, Inc., Athens, Georgia -- Development of a Quantitative Adverse Outcome Pathway Network to Assess Neurodevelopmental Toxicity of PFAS Mixture in C. Elegans;
   
• University of Houston, Houston, Texas -- Oral Toxicity Assessment of PAH Mixtures Using an in Vitro 3D Cell Culture Bioreactor Mimicking the in Vivo Intestinal Tract Environment;
   
• University of Massachusetts Boston, Boston, Massachusetts -- Whole Animal New Approach Methodologies for Predicting Developmental Effects of Air Pollutant Mixtures;
   
• University of North Carolina at Chapel Hill, Chapel Hill, North Carolina -- Wildfire Smoke Mixtures Toxicity Testing; and
   
• Wayne State University, Detroit, Michigan -- Assessment of Underlying Molecular Mechanisms Promoting Adipogenic Outcomes in Complex Mixtures.

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By Lynn L. Bergeson and Carla N. Hutton
 
The U.S. Environmental Protection Agency’s (EPA) New Chemicals Program will host a webinar on October 18, 2022, on EPA’s process for assessing the potential risks of new chemicals under Section 5 of the Toxic Substances Control Act (TSCA) and the types of data EPA considers in this assessment. The webinar will cover examples of quantitative and qualitative data unlikely to be accepted for engineering assessment, considerations EPA makes when evaluating data, and clarifications of common misconceptions in EPA’s new chemical assessments.
 
As reported in our June 27, 2022, memorandum, in June 2022, EPA announced a broad outreach effort to describe to stakeholders how EPA evaluates engineering data (i.e., data related to environmental release and worker exposure) provided for new chemical submissions and common issues that cause EPA to have to reconduct risk assessments (“rework”). The goal of this effort is to prevent delays of EPA’s new chemical reviews caused by rework.
 
This will be the second in a series of webinars intended to increase the efficiency and transparency of EPA’s new chemical determinations. As reported in our July 28, 2022, memorandum, in July 2022, EPA hosted the first webinar, analyzing common issues that cause EPA to have to rework risk assessments. Meeting materials are available for those who missed the first webinar.

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By Lynn L. Bergeson and Carla N. Hutton
 
The U.S. Environmental Protection Agency (EPA) announced on October 11, 2022, that the Office of Research and Development’s (ORD) Board of Scientific Counselors (BOSC) will review the Toxic Substances Control Act (TSCA) New Chemicals Collaborative Research Program. 87 Fed. Reg. 61313. The meeting will be held October 24-25, 2022, via videoconference. Attendees must register by October 23, 2022. Comments must be received by October 23, 2022, to be considered by BOSC. EPA states that requests for the draft agenda or to make a presentation at the meeting will be accepted until October 23, 2022.
 
BOSC is a federal advisory committee that provides advice and recommendations to ORD on technical and management issues of its research programs. The meeting agenda and materials will be posted on BOSC’s website. According to the Federal Register notice, proposed agenda items for the meeting include, but are not limited to, review of the New Chemicals Collaborative Research Program.
 
As reported in our March 14, 2022, memorandum on the draft document entitled “Modernizing the Process and Bringing Innovative Science to Evaluate New Chemicals Under TSCA,” the Office of Chemical Safety and Pollution Prevention (OCSPP) proposes to develop and implement a multi-year collaborative research program focused on approaches for performing risk assessments on new chemical substances under TSCA. On April 20-21, 2022, EPA held a virtual public meeting to provide an overview of the program and give stakeholders an opportunity to provide input. EPA has posted the meeting materials in the online docket. A summary of the meeting is available in our April 22, 2022, memorandum.

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By Lynn L. Bergeson and Carla N. Hutton
 
The U.S. Environmental Protection Agency (EPA) will hold a webinar on October 13, 2022, on its web-based Interspecies Correlation Estimation (Web-ICE) tool. According to EPA, protecting the diversity of species from the adverse effects of chemicals is a significant environmental challenge. EPA acknowledges that information on the effects of chemicals on species is either very limited or lacking entirely, making management and mitigation of environmental contaminants difficult. EPA developed the Web-ICE tool to allow toxicity extrapolation from standard test organisms to diverse taxa, including endangered species. The publicly-accessible application allows risk assessors and environmental managers from all sectors to estimate chemical toxicity to a diversity of fresh and saltwater invertebrates and fish, birds and mammals, and aquatic plants (algae) that may have limited toxicity data. The training webinar will provide an overview of Web-ICE, including a brief overview of ICE models, demonstration of its application with example case studies, and a tutorial on using the Internet application. Registration is open.

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By Lynn L. Bergeson and Carla N. Hutton
 
The U.S. Environmental Protection Agency (EPA) announced on August 22, 2022, that as part of its commitment to re-evaluate policies and practices under the Toxic Substances Control Act (TSCA) New Chemicals Program to ensure they adhere to statutory requirements and the Biden Administration’s executive orders and directives, it has updated its policy to discontinue the use of exposure modeling thresholds when assessing the health and environmental risks of new chemicals under TSCA. According to EPA, due in part to the automation of modeling, it has become less burdensome to complete these calculations. Furthermore, according to EPA, removing the thresholds supports President Biden’s Executive Order 13985, “Advancing Racial Equity and Support for Underserved Communities Through the Federal Government,” which calls on federal agencies to advance equity, including by reviewing and revising as needed government policies and programs impacting underserved communities.
 
The New Chemicals Program will implement this change by making minimal changes to the coding in the New Chemical Review application to remove the thresholds and will update standard operating procedures and training materials for exposure and human health risk assessors. EPA states that it will implement this policy change “as soon as feasible.” According to EPA, despite the resource challenges it is currently facing in the TSCA program, it anticipates that the change “will have minimal impact on the amount of time it takes to complete new chemical reviews and that the benefits gained from a more comprehensive accounting of all potential air and water releases will help ensure any needed protections are in place before a new chemical can come to market.”
 
More information and a detailed commentary that discusses thresholds of toxicological concern (TTC) are available in our August 22, 2022, memorandum.

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