EPA New Approach Methods: Efforts to Reduce Use of Vertebrate Animals in Chemical Testing
The Environmental Protection Agency has reaffirmed its commitment to reduce mammalian animal testing. EPA's use of gold standard science, including New Approach Methods (NAMs), is designed to protect human health and the environment while working to eliminate the use of mammals in testing by 2035. Prioritizing the development and use of NAMs will reduce the use of vertebrate animals in chemical testing while ensuring protection of human health and the environment.
What are New Approach Methods?
The definition of NAMs has evolved over time. Currently, it is a broadly descriptive reference to any non-vertebrate animal technology, methodology, approach, or combination thereof that can be used to provide information on chemical hazard and risk assessment. These include in vitro tests, in chemico assays, and in silico models. NAMs are functionally equivalent to “alternatives" to mammal testing.
Why Develop New Approaches?
The Toxic Substances Control Act (TSCA), as amended by the Frank R. Lautenberg Chemical Safety for the 21st Century Act, directs EPA to:
- reduce and replace, to the extent practicable and scientifically justified, the use of vertebrate animals in the testing of chemical substances or mixtures; and
- promote the development and timely incorporation of alternative test methods or strategies that do not require new vertebrate animal testing.
EPA uses many types of information to evaluate the potential risks of chemicals to human and ecological health. Due to the large number of chemicals regulated by EPA, there is a need for better, faster, and more cost-effective methods for chemical evaluation. Associated with this need is the goal of reducing, refining, and replacing the use of animals in testing as directed by the Lautenberg Act. NAMs are also more relevant to human relevant outcomes because they use human-relevant cells and tissues that are fit-for-purpose for decision making. These methods are also rigorously reviewed and validated across the scientific community to ensure the best available science is being used for testing. NAMs help to address potential adverse developmental outcomes that reflect the best available knowledge of human developmental biology and do so with less reliance on traditional animal testing.
Learn more about how EPA is assessing and managing chemicals under TSCA.
NAMs Research Approaches
EPA is actively developing, testing and applying NAMs to improve Agency approaches to evaluate the potential impacts of chemicals on human and ecological health. Working collaboratively with federal partners and other stakeholders, EPA is developing NAMS that will provide data to fill critical information gaps and build confidence for the use of these new approaches in regulatory decisions.
High-Throughput Toxicology
High-throughput toxicology tools and data support multiple regulatory and research programs across EPA. Of note, EPA previously announced Availability of New Approach Methodologies (NAMs) in the Endocrine Disruptor Screening Program (EDSP), including two validated computational models that integrate bioactivity data from multiple in vitro assays to screen for potential estrogen and androgen receptor effects. EPA is using these ToxCast estrogen and androgen pathway model scores as alternatives to four EDSP Tier 1 assays. Additionally, EPA used the ToxCast scores to prioritize more than 400 pesticide registration review cases and require further endocrine data where there was estrogen or androgen receptor bioactivity. EPA is now developing new versions of the estrogen and androgen pathway models that can be used to screen chemicals using a smaller number of assays. Beyond these efforts, EPA intends to advance and accelerate regulatory implementation of the EDSP by working with partners to establish high-throughput methods for steroidogenesis, thyroid, and associated models; deploy species extrapolation approaches; and maintain crucial interactive dashboard tools, such as the CompTox Chemicals Dashboard, for data interpretation, translation, and chemical prioritization. Learn more about High-Throughput Toxicology research.
Adverse Outcome Pathways
Successful adoption and use of NAMs in risk assessments and regulatory decision making depends upon developing confidence that new methods. To achieve this confidence, an understanding of both chemistry and biology is needed to establish the scientific rationale that supports the use of NAMs in evaluating potential chemical impacts. EPA is actively developing Adverse Outcome Pathways (AOPs) for high-priority pathways and chemicals, designing relevant case studies, and disseminating the results through the Collaborative Adverse Outcome Pathway Wiki (AOP-Wiki). Additionally, EPA is conducting in vitro and in vivo studies for high-priority AOPs to support predictive model development. EPA’s work on AOP will help to understand and define biological points of departure, actionable effect levels, and susceptibility factors for important chemicals of interest.
Additional Resources
- List of NAMs per Section 4(h)(2)(C) of TSCA
- Alternative Toxicity Testing Report to Congress
- TSCA Alternative to Mammal Testing
- Pesticides
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Work Plan
Prioritizing agency efforts to reduce vertebrate animal testing.
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Conferences
EPA will be hosting the 4th NAMs Conference November 5-6, 2024.
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Training
Access resources like recordings, worksheets, and user guides for EPA NAMs tools.