Alternative testing methods have many advantages over traditional animal tests—including being more humane—but implementing an alternative from idea to acceptance can take years.

Learn more about the step-by-step process, then check out our list of examples in action.

Step 1: Defining

The word "alternative" is used to describe any change in an animal test that achieves one or more of the "three Rs":

  1. Replaces a procedure that uses animals with a procedure that doesn't use animals.
  2. Reduces the number of animals used in a procedure.
  3. Refines a procedure to alleviate or minimize potential animal pain.

Step 2: Developing

Scientists at private companies, universities and government agencies are developing new cell and tissue tests, computer models and other sophisticated methods to replace existing animal tests. These alternatives are not only humane; they also tend to be more cost-effective, rapid and reliable than traditional animal tests.

Step 3: Validating

Once an alternative test has been developed by a scientist, it must be scientifically "validated" or evaluated in multiple laboratories to see if its results reliably predict outcomes in people. Validation is sometimes a frustratingly slow process and the United States has unfortunately proved to be far slower at validating alternatives than the European Union.

Step 4: Accepting

After an alternative has been scientifically validated, it is then up to government authorities to decide whether, and to what extent, they will accept the use of the alternative to replace, reduce or refine animal use. The opinions of government regulators strongly influence the extent to which private companies use available alternatives instead of traditional animal tests.

Examples of Alternatives

More than 50 different alternative methods and testing strategies have been developed, validated and/or accepted by international regulatory authorities. These are a few examples:

  • Using blood from human volunteers to test for the presence of fever-causing contaminants in intravenous medicines can save hundreds of thousands of rabbits each year from traditional "pyrogen" tests.
  • EpiSkin?, EpiDerm? and SkinEthic, each composed of artificial human skin, can save thousands of rabbits each year from painful skin corrosion and irritation tests.
  • The Bovine Corneal Opacity and Permeability Test and Isolated Chicken Eye Test use eyes from animals slaughtered for the meat industry instead of live rabbits to detect chemicals and products that are severely irritating to the eyes.
  • The 3T3 Neutral Red Uptake Phototoxicity Test can replace the use of mice and other animals in the testing of medicines and other products for their potential to cause sunlight induced "phototoxicity."
  • A combination of in vitro test methods and already available human and animal data may be used to determine the potential for skin sensitization instead of using the traditional guinea pig and mouse tests.
  • When testing to determine chemical concentrations that are deadly to fish and other aquatic life, use of the Fish Threshold Method can reduce the numbers of fish used by at least 70 percent compared with standard test methods.

A complete list of validated and/or accepted alternative methods and testing strategies is available on the Humane Society of United Society partner site