Types of Animal Tests

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Product testing on animals was born from the belief that animals respond the same way that humans do when exposed to certain substances, which we now know to be false. Most animal tests on cosmetics and personal care and household products today are conducted at the ingredient level, not on finished products. Mice, rats, rabbits, fish and guinea pigs are the most commonly used animals.

Types of Tests 

 

Draize Test

The most notorious of animal tests, the Draize eye test was developed in 1944 to asses eye irritation. A substance is placed in one eye of a rabbit, with the other eye serving as a control. The rabbits are restrained, preventing them from responding naturally to the irritation, and their eyes are evaluated at regular intervals up to 14 days. They can suffer from redness, bleeding, ulcers, and even blindness, and are likely killed upon completion of the experiment.

Acute Toxicity Testing

Acute toxicity testing is used to determine the danger of exposure to a chemical by mouth, skin, or inhalation. An older version of the test, the Lethal Dose 50 (LD50) involved poisoning large numbers of animals until at least half of them die. The fixed dose method, which does not use death as an endpoint, focuses instead on signs of ailments or suffering. During these tests, animals may endure excruciating pain, convulsions, loss of motor function, and/or uncontrollable seizures. The animals are killed at the end of the test so they can be studied. Rats and mice are the animals most often used in acute toxicity testing.

Skin Irritation Testing

Skin irritation tests assess the potential of a substance to cause damage to the skin, including itching, swelling, and inflammation. The test most often uses rabbits and involves placing a chemical on a shaved patch of skin and using another shaved patch as a control.

Ecotoxicity Testing

Ecotoxicity tests are used to analyze potential negative effects of chemicals entering the environment. The standard acute toxicity test, the LC50 (lethal concentration 50%), uses fish as a subject and measures the concentration of a chemical that kills 50% of the test population in a 96 hour period. Chronic fish tests last from seven to more than 200 days and the fish are evaluated for growth, hatching and spawning success, and mortality.

Carcinogencity Tests

A carcinogen is a substance or mixture of substances that causes cancer or increases the incidences of cancer. In this test, a chemical is administered orally, placed on the skin, or inhaled over a prolonged duration to mice or rats. After the study is completed, the animals are killed and their tissues and organs are examined for evidence of cancer.

Reproductive and Developmental Toxicity

Reproductive toxicity tests measure the toxic effects of a substance on the reproductive ability of an animal, usually a rat or mouse, and the toxic effects on the development of its offspring. Developmental toxicity testing involves giving pregnant female animals, usually rats and rabbits, doses of chemicals administered orally. The animals are killed just prior to delivery and the fetuses are examined for any sign of toxic effects by the test substance.