Exploring current read-across applications and needs among selected U.S. Federal Agencies

Area of Science:

• Toxicology and Chemical Risk Assessment
• Regulatory Science
• Data Gap-Filling Methodologies

Background:

• Read-across is an established technique for filling data gaps in regulatory submissions.
• While extensively used by the US Environmental Protection Agency (EPA) under the Toxic Substances Control Act (TSCA), its application across other federal agencies is less understood.
• The Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM) established a read-across workgroup to enhance capacity and harmonize approaches.

Purpose of the Study:

• To outline the objectives and scope of the new ICCVAM read-across workgroup.
• To survey and summarize the current use, tools, and identified needs for read-across among participating US federal agencies.
• To provide insights into the varying applications of read-across based on agency-specific decision contexts.

Main Methods:

• Convening an ad hoc workgroup under ICCVAM.
• Surveying federal agencies represented on the workgroup regarding their read-across practices.
• Analyzing current applications, tools, and identified needs for read-across.
• Presenting case studies to illustrate inter-agency variations in read-across approaches.

Main Results:

• The EPA demonstrates the most extensive experience with read-across among surveyed agencies.
• Several agencies expressed a need for a broader understanding of available read-across tools and guidance.
• Agency-specific decision contexts influence the application of read-across methodologies.

Conclusions:

• The ICCVAM workgroup serves to advance the understanding and consistent application of read-across across US federal agencies.
• Harmonizing read-across approaches will strengthen regulatory science and data gap-filling efforts.
• Further development and dissemination of guidance and tools are needed to support broader agency adoption and capacity building.