For decades, toxicology has relied heavily on animal testing to evaluate chemical safety and support regulatory decision-making. In recent years, increasing attention has been given to a broad range of scientific tools known as New Approach Methodologies (NAMs), a term that encompasses in vitro methods, computational models, and other technologies that can provide information about potential health effects while reducing, refining, or replacing animal testing.
However, many of the approaches now grouped under the NAMs umbrella are not entirely new. In vitro testing methods, for example, have been used for decades as supplemental tools in toxicology, and advances in cell biology, molecular sciences, and computational methods have steadily expanded their capabilities. What is changing today is the growing interest among regulators, researchers, and industry in leveraging these approaches to generate more human-relevant data and advance the way potential health risks are assessed.
In addition to in vitro assays, tools associated with NAMs include advanced cell-based models, omics technologies and bioinformatics, computational toxicology, artificial intelligence (AI), and organ-on-a-chip technologies. Although many of these approaches have been in development for years, advances in science and technology have significantly expanded their capabilities. As a result, regulatory agencies, researchers, and industry are increasingly exploring how NAMs can be incorporated into safety assessments, signaling a shift from primarily research-focused applications toward broader use in regulatory decision-making.
For organizations involved in chemical manufacturing, pharmaceuticals, consumer products, and environmental health, understanding this shift will be essential.
What Are NAMs?
New Approach Methodologies (NAMs) are scientific methods used to evaluate chemical hazards and health effects without relying solely on traditional animal studies. Many NAMs are designed to provide data that is more directly relevant to human biology while supporting faster and more efficient safety evaluations.
Examples include:
- Human cell and tissue-based testing (in vitro assays): using cultured human cells, three-dimensional tissue models, or advanced cell systems to evaluate toxicity, mechanisms of action, and biological responses.
- Organ-on-a-chip technologies: micro-engineered systems that mimic the structure and function of human organs, such as liver-, lung-, or heart-on-a-chip platforms.
- Omics and bioinformatics: applying genomics, transcriptomics, proteomics, and metabolomics data, combined with computational analysis, to identify biological pathways affected by chemical exposures.
- Computational toxicology models, AI, & machine learning tools: using predictive models, large datasets, and artificial intelligence to estimate toxicity, prioritize chemicals for testing, and identify potential hazards.
- Biomonitoring and read-across approaches: incorporating human exposure data and information from structurally similar chemicals to fill data gaps and support risk assessments.
- Integrated testing strategies: combining multiple lines of evidence from experimental, computational, and human data sources within a weight-of-evidence framework.
Why Are NAMs Gaining Momentum?
In June 2026, U.S. Environmental Protection Agency (EPA) announced additional actions to reduce and ultimately eliminate mammalian animal testing, including expanding the agency’s list of accepted NAMs and creating a streamlined process for evaluating new non-animal testing technologies. These actions build upon EPA’s renewed commitment to phase out mammalian testing by 2035 and further signal increasing federal support for human-relevant alternative methods.
In 2025, the U.S. Food and Drug Administration (FDA) released its Roadmap to Reducing Animal Testing in Preclinical Safety Studies and has since introduced several initiatives aimed at increasing the use of human-relevant testing methods. Recent actions include reducing reliance on certain long-term animal studies, qualifying the agency’s first AI-based drug development tool, and publishing a framework for evaluating NAMs in regulatory submissions.
At the same time, National Institute of Health (NIH) is continuing to invest in research and validation efforts that support broader adoption of these approaches through the Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM) within the National Toxicology Program (NTP).
What Could This Mean for Industry?
While NAMs are unlikely to replace traditional testing overnight, they may influence how organizations approach safety evaluations in the future. Many regulators are now exploring “weight-of-evidence” approaches that combine data from multiple sources, including NAMs, to support decision-making.
Potential benefits include:
- Faster generation of toxicological data
- Improved understanding of human-relevant biological responses
- Enhanced risk assessment capabilities
- Greater flexibility in regulatory submissions
- Reduced uncertainty during product development
- Reduction or replacement of traditional lifetime cancer bioassays in animals
Looking Ahead
The future of toxicology will likely involve a combination of traditional testing methods, computational tools, advanced laboratory models, and AI-driven technologies.
What makes NAMs noteworthy is not simply the technology itself, but the increasing acceptance of these approaches by regulatory agencies. Recent FDA initiatives suggest that NAMs are no longer viewed solely as experimental tools but as an important component of the next generation of safety assessments. The U.S. Pesticide Program includes a waiver application to use NAMs as part of a weight-of-evidence (WoE) approach to replace one of the two required 2-year animal bioassays. Organizations that stay informed about these developments may be better positioned to adapt as regulatory expectations and scientific best practices continue to evolve.
How RHP Risk Management Can Help
RHP Risk Management is an environmental and occupational health consulting firm of scientists, including toxicologists, epidemiologists, public health professionals, and risk assessment specialists.
RHP scientists actively monitor developments in toxicology, risk assessment, and regulatory science, including the rapidly evolving field of NAMs. Our staff participate in professional organizations such as the Society of Toxicology (SOT), attend scientific conferences and workshops focused on alternative testing approaches, and track emerging guidance from agencies including the FDA, EPA, OECD, and ECHA. RHP’s Dr. Melanie Buser will be attending ICCS’s 2026 Symposium on “Advancing Animal-Free Science Through Innovation & Engagement” in Brussels, Belgium on June 15th.
As toxicology and risk assessment methodologies continue to evolve, organizations may face new questions regarding regulatory expectations, exposure assessments, and chemical safety evaluations. Contact RHP experts to reduce uncertainty and enable confidence in decision-making by delivering reliable, reproducible, and relevant data. Through early and active stakeholder engagement, we provide customized solutions that support clients with their specific goals.