Animal Testing Factsheet

Every now and again, you will encounter someone who claims that animal testing is not harmful or dangerous to animals. If so, please share these facts with them.

Product Testing: Toxic & Tragic

Every year, millions of animals are poisoned and killed in barbaric tests that were crudely developed as long ago as the 1920s to evaluate the toxicity of consumer products and their ingredients.

Rats, mice, guinea pigs, rabbits, and other animals are forced to swallow or inhale massive quantities of a test substance or endure the pain of a chemical eating away at their sensitive eyes and skin––even though the results of animal tests are often unreliable or not applicable to humans.

Acute Toxicity Tests

To determine the toxic consequences of a single, short-term exposure to a product or chemical, the substance is administered to animals (usually rodents) in extremely high doses via force-feeding, forced inhalation, and/or absorption through the skin. Animals in the highest dose groups may endure severe abdominal pain, diarrhea, convulsions, seizures, paralysis, and bleeding from the nose, mouth, and genitals before they ultimately die.(1)

Acute toxicity testing began during the World War I era with the now infamous lethal dose 50 percent (LD50) test, which even today, remains the most common form of animal-poisoning study. In this test, groups of animals are force-fed increasing amounts of a substance until 50 percent of them die.

Despite its decades of use, the LD50 test and its more contemporary adaptations have never been scientifically validated to confirm that their results are indeed predictive of chemical effects in people. One international study that examined the results of rat and mouse LD50 tests for 50 chemicals found that these tests were able to predict toxicity in humans with only 65 percent accuracy––while a series of human cell-line tests was found to predict toxicity in humans with about 75 percent accuracy.(2)

Eye and Skin Irritation/Corrosion Tests

The Draize eye- and skin-irritation/corrosion test dates back to the 1940s.(3) During this test, rabbits are often immobilized in full-body restraints while a substance is dripped or smeared into their eyes or onto their shaved skin. Laboratory technicians then record the damage at specific intervals for hours or days.

Rabbits may suffer swollen eyelids, irritated and cloudy eyes, and inflamed skin, and in the case of irreversible corrosive damage, they may endure ulcers, bleeding, bloody scabs, or blindness.

The scoring of eye and skin damage in the Draize test is highly subjective, and therefore, different laboratories—and even different tests within the same laboratory—often yield different results. In addition, rabbits’ eyes are anatomically and physiologically different from and tend to have stronger reactions to chemicals than humans’ eyes.

One study found that the Draize test “grossly overpredicted the effects that could be seen in the human eye,” and another concluded that the test “does not reflect the eye irritation hazard for man.”(4) In contrast, a clinical skin patch test conducted on human volunteers has been shown to produce skin-irritation data that are “inherently superior to that given by a surrogate model, such as the rabbit.”(5)

Cancer Tests

Even though a number of highly sensitive non-animal tests for detecting chemical-induced genetic mutations have been available and in widespread use for decades, government regulations continue to require companies to poison animals to see whether they develop cancer.

A standard animal test called the “rodent cancer bioassay” subjects mice and rats to a lifetime of chemical exposure and is carried out on all new and reformulated pesticides, food additives, and drugs.(6)

A single cancer bioassay costs an average of $3 million.(7) The scientific community admits that these tests have a false positive rate of more than 70 percent.(8) One Pfizer researcher wrote, “[W]e should face the fact that the behemoth of the rodent bioassay is identifying hundreds of chemicals as ‘carcinogens’ that do not contribute at all to human cancer.”(9)

Product Tests

No law requires that cosmetics and household products be tested on animals. The Food and Drug Administration (FDA) “urges cosmetic manufacturers to conduct whatever tests are appropriate to establish that their cosmetics are safe” but “does not specifically mandate animal testing for cosmetic safety.”(10) Likewise, household products regulated by the Consumer Product Safety Commission (CPSC) do not have to be tested on animals.

A summary of the CPSC’s animal-testing policy, as published in the Federal Register, states that “it is important to keep in mind that neither the FHSA [Federal Hazardous Substances Act] nor the Commission’s regulations require any firm to perform animal tests. The statute and its implementing regulations only require that a product be labeled to reflect the hazards associated with that product.”(11)

Tests That Are Required by Law

In contrast, lawn fertilizers, weed killers, and household cleaners that make “germ killing” or “antibacterial” claims on their labels are regulated as pesticides by the Environmental Protection Agency.(12) By law, every pesticide must undergo dozens of separate animal tests before it can be marketed, which spells suffering and death for many animals.(13) The FDA has similar testing requirements for drugs as well as chemicals that are used as additives or preservatives in processed foods.(14,15)

Alternatives to Animal Tests

Today, hundreds of cosmetics and household-products companies have turned their backs on animal testing and begun taking advantage of the many sophisticated non-animal test methods available today, which range from cell and tissue cultures to computerized “structure-activity relationship” models.

For example, EPISKIN™ and EpiDerm™, multi-layered skin models made up of cultures of human skin cells, have been scientifically validated and accepted around the world as total replacements for rabbit skin corrosion studies.(16)

Similarly, the cell-based “3T3 Neutral Red Uptake Phototoxicity Test” has become a widely accepted alternative to the use of guinea pigs and mice to assess sunlight-induced skin irritation.(17) PETA is urging U.S. regulatory agencies to accept these and other valid non-animal test methods as part of its “Give the Animals 5” campaign (visit for more information).

Where validated non-animal replacements are not yet available or fully validated, PETA lobbies companies and the government to provide the necessary funding for research and development and works closely with organizations that specialize in test-method validation, such as the European Centre for the Validation of Alternative Methods and the Institute for In Vitro Sciences to bring new non-animal test methods into the mainstream.

Compassion in Action

Caring consumers who boycott animal-tested products play a vital role in pushing companies and government agencies to adopt more relevant and humane non-animal test methods. Spurred by public outrage, the European Union has voted to outlaw cosmetics testing on animals as well as the sale of animal-tested cosmetics by 2013.(18)

To help consumers identify products that are cruelty-free, PETA’s Caring Consumer Project ( clarifies non-animal testing terminology and procedures, compiles information on the testing policies of companies, and publishes a list of companies that have signed our statement of assurance to confirm that they do not conduct or commission animal tests of their products, ingredients, or formulations.

Shoppers can support this project by purchasing products that comply with PETA’s cruelty-free company standard, boycotting those that don’t, and asking local stores to carry cruelty-free items.

Everyone seeking to stop animal tests should also urge government regulatory agencies to accept non-animal test methods immediately. Visit to view current action alerts and learn more about how you can help put an end to product testing on animals.


(1) Organisation for Economic Co-Operation and Development, “Guidance Document on the Recognition, Assessment, and Use of Clinical Signs as Humane Endpoints for Experimental Animals Used in Safety Evaluation,” OECD Environmental Health and Safety Publications, Series on Testing and Assessment, Nov. 2000.

(2) B. Ekwall, “Overview of the Final MEIC Results: II. The In Vitro-In Vivo Evaluation, Including the Selection of a Practical Battery of Cell Tests for Prediction of Acute Lethal Blood Concentrations in Humans,” Toxicology in Vitro, 13 (1999): 665-673.

(3) M.K. Robinson et al., “Non-Animal Testing Strategies for Assessment of the Skin Corrosion and Skin Irritation Potential of Ingredients and Finished Products,” Food and Chemical Toxicology, 40 (2002): 573-592.

(4) R. Roggeband et al., “Eye Irritation Responses in Rabbit and Man After Single Applications of Equal Volumes of Undiluted Model Liquid Detergent Products,” Food and Chemical Toxicology, 38 (2000): 727-734.

(5) “Validity and Ethics of the Human 4-h Patch Test as an Alternative Method to Assess Acute Skin Irritation Potential,” Contact Dermatitis, 45 (2001): 1-12.

(6) John R. Bucher, “The National Toxicology Program Rodent Bioassay,” Annals of the New York Academy of Sciences, 982 (2002): 198-207.

(7) Karen Young Kreeger, “Of Mice and Humans,” The Scientist, 27 May 1996.

(8) Carl L. Alden, “Safety Assessment for Non-Geotoxic Rodent Carcinogens: Curves, Low Dose Extrapolations, and Mechanisms in Carcinogenesis: Commentary,” Chemical Carcinogenese: Epigenetic Mechanisms and Dose Response, 9 (2000).

(9) A.M. Monro, “The Rodent Bioassay Is Being Wrongly Used to Identify ‘Carcinogens’” BELLE Newsletter, 5 (1996).

(10) U.S. Food and Drug Administration, “Animal Testing,” Office of Cosmetics and Colors Factsheet, Center for Food Safety and Applied Nutrition, 3 May 1999.

(11) “Animal Testing Policy,” Consumer Product Safety Commission, 49 FR 22522, 30 May 1984.

(12) “About Pesticides,” Environmental Protection Agency, 10 May 2004.

(13) U.S. Environmental Protection Agency, “Protecting the Public From Pesticide Residues in Food,” Pesticides: Topical & Chemical Fact Sheets, 19 May 2003.

(14) Graham Lawton, “The Quest for Valid Alternatives,” Chemistry and Industry, 19 May 1997.

(15) National Library of Medicine, “Toxicology Tutor I Basic Principles,” National Institutes of Health, 14 May 2001.

(16) National Toxicology Program, “Episkin™, EpiDerm™, and Rat Skin Transcutaneous Electrical Resistance (TER), In Vitro Test Methods for Assessing the Dermal Corrosivity Potential of Chemicals,” National Institute of Environmental Health Sciences, Aug. 2001.

(17) Michael Balls and Guy Corcelle, “Statement on the Scientific Validity of the 3T3 NRU PT Test (An In Vitro Test for Phototoxic Potential),” European Centre for the Validation of Alternative Methods, 3 Nov. 1997.

(18) The American Veterinary Medical Association, “The EU Bans Cosmetics Testing on Animals,” JAVMA News, 1 Mar. 2003.