Animal TestingConsidering the furor raised about using animals for testing, are therealternatives to using such testing? What are the main tests that use animals andalternatives that would achieve similar results? There is a lot of controversyabout using animals to test cosmetics. Animal rights organizations feel that itis unnecessary and uncalled for. The Food and Drug Administration have no lawthat cosmetics have to be tested on animals. The main reason cosmetic companiescontinue to use animals to test their products instead of the alternatives isbecause they are afraid of getting laws suites. The alternatives to animaltesting have not yet been validated, therefore if they were taken to court theymay not win the case if these alternatives were used. If companies wouldrecognize the consistency and validity of these products then maybe animaltesting will not be needed.
Two of the main tests that companies use are theDraize Test and the Irritancy Test. These tests are not needed because there areother tests that don’t use animals and give the same if not better results. TheDraize Test is used to measure the harmfulness of the ingredients that are incosmetics and household products. The test involves dripping the substance intoa rabbit’s eye and recording the results.
Scientists use rabbits because theyhave large eyes and no tear ducts to wash away the chemical. Reactions vary fromslight irritation to ulceration and complete blindness. The rabbits arerestrained to keep from clawing their eyes. All of the animals are usuallykilled at the end of the test, or “recycled” into toxicity tests. R.
Sharpe writes in his book, The Cruel Deception: The Use of Animals in MedicalResearch, the Draize Test should not be used because there are a number ofdifferences between the human eye and the rabbit eye. Rabbits have a thirdeyelid, they have less tear fluid to wash away irritants, they have a morealkaline eye (humans have a pH of 7. 1-7. 3, rabbits have a pH of 8. 2), andrabbits have a thinner cornea. Overall the Draize Test overestimates howirritating a product is to the human eye because rabbits eyes are more sensitivethan the human eye (Freeberg).
This test is also invalid because of thedifferences in the way the damage is evaluated. In a study performed by CarnegieUniversity of Pittsburgh twelve substances were sent to twenty-four differentlaboratories. The results that came back for the same substances ranged frommild to severe reactions. Since the test itself is so unreliable companiesshould look into some alternatives. An alternative to using animals to test howharmful an ingredient is to the eye is a method called Eytex. Eytex uses avegetable protein taken from jack beans.
This clear protein gel turns clear whenit comes in contact with irritating substances. This process is more accuratethan the Draize Test is because the “damage” is measured by aspectrophotometer and not estimated by a person. The Eytex Test agrees well withthe Draize Test, although the results should be compared to human eyeirritation. Until better methods come along this test could be used instead ofanimals. Here are some comparisons of the Eytex Test to the Draize Test: %Agreement %Irritants Substances 85% 89% 101 80% 100% 465 The second column showshow closely related Eytex results agreed with Draize Test results, the thirdcolumn shows what percentage of irritants were identified by Eytex, and the lastcolumn shows the number of substances were tested.
There is also close agreementbetween laboratories on the results. One study showed 90% agreement between sixdifferent laboratories and ten substances (Kelly). Another study sent sixtysubstances to twelve different laboratories. In nine of thirteen categories ofsubstances there was 100% agreement between the laboratories. There was 83%-93%agreement between the other four categories (Kelly).
This shows that there ismore agreement between laboratories in the Eytex Test than the Draize Test. Another type of test that is used to establish the irritancy of a product is theSkin Irritancy Test. This test measures how a substance irritates the skin. Patches are shaved off the backs of rabbits and slightly abraded to make themmore sensitive. The substance is placed on the bare skin and covered with gauzefor four hours.
Researchers look for signs of redness, inflammation, weeping orscabs (Animal Liberation). These tests have been shown to be invalid. In onestudy household products were tested on rabbits, guinea pigs and humans. Onlyfour of the substances were non-irritating to all of the subjects. Twelve weremore irritating in one or more of the species and three were less irritating inone or both of the animals than in humans (Nixon). In another study twelvesubstances were tested on human and rabbit skin, the results were similar onlyfor the two most irritating substances.
The remaining ten were irritating to therabbits but not the humans (Phillips). This shows that rabbits’ skin is alsomore sensitive than humans. There are a number of alternatives to this test. They include reconstructed human epidermis, the Microphisometer, and computermodeling. Reconstructed human epidermis is a multi-layered human skin grown inthe laboratory and can be used to test skin irritancy.
There are different waysto measure the damage an irritating substance causes. Cells can be examinedunder a microscope, membrane damage can be assessed by leakage of enzymes, orinflammation can be determined by release of interleukins (Animal Liberation). Whichever method is used, the results can be measured accurately, unlike theskin irritancy tests done on animals where observers estimate the degree ofswelling or redness. Results from this test have so far agreed well with animalstudies, although ideally they should be compared to human information (Ponec). The microphysiometer is an instrument that detects small changes in the pH ofthe pH of the cell culture nutrient fluid (changes in lactate, CO2 production).
When the microphysiometer measured how munch of a product it took to depress themetabolic rate of human skin by 50% there was very good agreement with animaltests as shown in the table below (Parce). Chemical Animal IrritancyMicrophysiometer 1 mild 0. 1 2 mild 0. 5 3 moderate-mild 0. 7 4 moderate-mild 0.
8 5moderate-mild 0. 9 6 moderate 1. 7 7 severe-moderate 3. 9 8 severe 4.
1 The tableshows that the Microphysiometer test rated the irritancy of the eight chemicalsin the same order as the animal tests, with the same kind of increase. The finalalternative to using animals for skin irritancy testing is computer modeling. Expert computer systems are used to predict the irritancy of new substancesbased on what is already known about substances with a similar chemicalstructure. This approach is called Quantitative Structure-Activity Relationship.
(Animal Liberation). This system is very reliable. A New York company calledHealth Designs shows that computer modeling distinguished severe irritants fromothers in 91. 5% of the cases.
It distinguished non-irritants from others in 93%of the cases (Sharpe). Animal testing has brought about many discoveries andcures for many diseases, but in the case of household products and cosmeticsanimals are not needed. There are many alternatives that are being used, andshould be used by all companies. Steps need to be taken to validate thesealternatives so cosmetic companies will have no dought about using thesealternative methods instead of using animals. Steps can be taken toward endinganimal testing for cosmetics by refusing to buy anything that was tested onanimals and writing to the companies insisting that they end the testing.
No oneperson can do it alone, but together as a whole it can come to an end. BibliographySharp R, The Cruel Deception: The use of Animals in Medical Research,Wellinborough: Thorsons Publishing Group, 1988 Freeberg F, Griffith J, Bruce R; Bay P, “Correlation of animal test methods with human experience forhousehold products”, Journal of Toxicology – Cutaneous Toxicology, 184, vol1 (53-64) Philips L, Steinberg M, Maibach H ; Akars W, “A comparison ofrabbit and human skin response to certain irritants”, Toxicology andapplied Pharmacology, 1972, vol 21 (369-382) Nixon G, Tyson C ; Wertz W,”Interspecies comparisons of skin irritancy”, Toxicology and appliedPharmacology, 1975, vol 31 (481-490) Kelly C, “An in vitro method ofpredicting ocular safety”, Drug and Cosmetic Industry, September 1988(54-64) Ponce M, “Reconstructed human epidermis in vitro: an alternative toanimal testing”, Alta, 1995, vol 23 (97-110) Internet All for Animals,Animal Testing alternatives, accessed Nov. 8, 1998 http://www. allforanimals. com/alternatives1.
htmPhysician’s Committee for Responsible Medicine, Are There Valid ResearchMethods, published: spring 1997, accessed Nov. 23, 1998 http://www. werple. net.
au/antiviv/valid. htmAnimal Liberation, Product Testing, published: May 23,1998, accessed: Nov. 23,1998 http://www.animalliberation.org.au/skineye.html
