Types of Cosmetic Testing
Draize Test Eye Irritancy Test
The Draize Test is one of the most common type of cosmetic testing. This test is named after the scientist, John Draize, in 1944. For this test, albino rabbits are used since their skin is much more sensitive. Liquid, flake, granule, and powdered substances are placed into one of the rabbits’ eyes, and then the progressive deterioration of the eyes is recorded while the other eyes act as the control.
To administer the test, 100 mg of a concentrated substance is placed into the eyes of a number of rabbits. These rabbits are usually restrained to minimize movement. This prevents them from responding naturally to the irritants. Their eyes are also held open with clips and the rabbits are able to break their necks or backs while struggling to escape. The duration of the test is often 72 hours, and damage to the eyes are recorded every 24 hours. The irritants cause swelling of the eyelid, inflammation of the iris, ulceration, bleeding, blindness, and the rabbits are very likely killed upon completion of the experiment.
Anesthetics are usually not given because experimenters claim that the anesthetics would interfere with the test results and even if anesthesia is administered, the pain relief is only temporary.
Guinea Pig Maximization Test
The Guinea Pig Maximization Test was invented in 1969 by Magnusson and Kligman to test for skin sensitization. Essentially, it is a test used to determine if a chemical substance causes an allergic reaction. To perform this test, the substances to be tested are applied on the surface or injected onto the guinea pig’s shaved skin. A chemical adjuvant is injected along with the test substance to encourage the immune reaction, and multiple doses are applied to create an allergic reaction. The results collected from the guinea pig tests for skin sensitization are subjective since the chemical substance is assessed according the the appearance of the skin. Moreover, the process of applying these chemicals to the guinea pigs, injecting them and delivering with an adjuvant, is not congruent with human use.
LD50 Test
The LD50 test stands for Lethal Dose 50. The idea of LD50 was invented by J.W. Trevan in 1927 to estimate the poisoning potency of drugs and medicines used at that time. This test determines the acute toxicity dosage of a substance that will kill 50% of the animals tested on. Acute toxicity describes the ability of a chemical to cause effects soon after one administration or a four hour exposure to the chemical in air.
LD50 tests are performed using the pure form of the chemical. The substance tested can be administered orally, topically, intravenously, or through respiration. Rats, mice, rabbits, and guinea pigs are commonly used for this test. During the test, the animals will have to endure excruciating pain, convulsions, loss of motor function, and seizures. At the end of the test, the animals are killed and a necropsy is performed to examine the internal damage.