Alternatives to Animal Testing

science tubes in lab

Scientists often study the effects of drugs and chemicals on animals before they deem them safe for humans.

When possible, they try to perform these toxicology tests using biochemical or cell-based (in vitro) systems instead of with animals such as mice. For example, researchers successfully created in vitro methods to identify severe eye irritants and substances that could cause allergic contact dermatitis.1  However, the development of in vitro tests that can reliably identify chemical hazards resulting in cancer or birth defects is more difficult because of the complexity of the biological processes involved.

Computer programs with advanced systems based on large chemical databases can predict a chemical's toxicity, reducing the need for animal testing in some situations.

The concept of replacing, reducing, or refining replacing, reducing, or refining animal use in research and testing was first described more than 60 years ago2 and is commonly referred to as 3Rs:

  • Replacing: A test method that substitutes traditional animal models with non-animal systems such as computer models or biochemical or cell-based systems, or replaces one animal species with a less developed one (for example, replacing a mouse with a worm).
  • Reducing: A test method that decreases the number of animals required for testing to a minimum while still achieving testing objectives.
  • Refining: A test method that eliminates pain or distress in animals, or enhances animal well-being, such as by providing better housing or enrichment.

Test methods that incorporate the 3Rs are referred to as new alternative methods.

  1. Löwa A, Jevtić M, Gorreja F, Hedtrich S, 2018. Alternatives to animal testing in basic and preclinical research of atopic dermatitis. Exp Dermatol. 27(5):476-483. [Abstract Löwa A, Jevtić M, Gorreja F, Hedtrich S, 2018. Alternatives to animal testing in basic and preclinical research of atopic dermatitis. Exp Dermatol. 27(5):476-483.]

What is NIEHS Doing?

NIEHS, an ICCVAM member agency, supports development of alternative methods to animal testing in its in-house research and through grants to external researchers and small businesses.

The National Toxicology Program (NTP) Interagency Center for the Evaluation of Alternative Toxicological Methods (NICEATM) conducts many of these research activities, including:

  • Conducting and publishing analyses and evaluations of data from new, revised, and alternative testing approaches.
  • Providing information to test method developers, regulators, and regulated industry through its website and other communications.
  • Organizing workshops and symposia on topics of interest.
  • Providing bioinformatics and computational toxicology support to NTP and NIEHS projects, especially those related to Tox 21, a program from the NTP in collaboration with other agencies that researchs, develops, evaluates, and translates innovative test methods to better predict how substances may affect humans and the environment.

NICEATM scientists publish scientific papers describing activities relevant to alternative methods development. These activities include evaluating new methods and approaches, and developing tools and compiling reference data for use by test method developers. They also report on related workshops, review alternative methods, and comment on testing status.

NICEATM supports the Interagency Coordinating Committee on the Validation of Alternative methods (ICCVAM), which evaluates and prepares recommendations on test methods proposed for regulatory use. Test methods recommended by ICCVAM and accepted by U.S. and international regulatory authorities include ways to assess hazards for eye and skin irritation, acute toxicity, and skin sensitization.

Further Reading

Stories from the Environmental Factor (NIEHS Newsletter)

Additional Resources

    This content is available to use on your website.

    Please visit NIEHS Syndication to get started.