Alternatives to Animal Testing

Alternative test methods are test methods that reduce, refine, or replace animal use in research and testing. Reduction, refinement, and replacement are commonly referred to as “the 3Rs”. The 3Rs concept was first described by William Russell and Rex Burch in their 1959 book The Principles of Humane Experimental Technique.

What do "reduce, refine, or replace" mean in the context of animal use in research and testing?

• A test method that reduces animal use decreases the number of animals required for testing while still achieving testing objectives.
• A test method that refines animal use lessens or eliminates pain or distress in animals, or enhances animal well-being.
• A test method that replaces animals substitutes traditional animal models with nonanimal systems such as computer models or biochemical or cell-based systems, or replaces one animal species with a less highly developed one (for example, replacing a mouse with a worm).

Why is safety testing performed on chemical products?

U.S. regulatory agencies require testing of consumer products, medicines, and industrial and agricultural chemicals to identify potential health and safety hazards. Testing these substances enables appropriate hazard classification and labeling, which in turn enables informed decisions about responsible use, storage, and disposal. All toxicity test methods used for regulatory purposes must be based on sound science and able to adequately identify hazards.

Is there a requirement to consider alternative methods before animals are used for testing?

Yes. U.S. laws require that alternatives must be considered before using animals for research and testing.

• The Animal Welfare Act requires that Institutional Animal Care and Use Committees in facilities where research and testing using animals is done approve proposed animal use and ensure that alternatives are being used where appropriate.
• The Public Health Service (PHS) Policy on Humane Care and Use of Laboratory Animals addresses the use of animals by NIH grantees and within NIH and other institutions under the Public Health Service. The PHS Policy requires that proposals justify the animal use, the number of animals to be used, and the specific procedures to be used.

Are Federal agencies required to support the development of alternative test methods?

Yes.

• The NIH Revitalization Act of 1993 directed NIH to support research to reduce, refine, and replace animal use in biomedical research, and to develop and validate methods that will reduce and replace animals in acute and chronic safety testing.
• The ICCVAM Authorization Act of 2000 established the Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM) to coordinate activities within the Federal government relevant to new test method evaluation, acceptance, and use. ICCVAM is made up of representatives of 15 U.S. Federal agencies that use or generate toxicity testing information.

Why are animals still used for safety testing?

Human and animal responses to chemicals are complex and difficult to accurately assess using only biochemical or cell-based (“in vitro”) systems or computer models. No single in vitro test method is currently available to serve all regulatory needs for a specific testing area. In some areas, such as identification of severe eye irritants and substances that could cause allergic contact dermatitis, major progress has been made in reducing and replacing animal use. For other hazards, such as identification of substances that can cause cancer or birth defects, development of in vitro tests that reliably identify hazards is more difficult because of the number of different mechanisms involved in these complex biological processes.