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Animal Testing Essay Research Paper Considering the

Animal Testing Essay, Research Paper

Considering the furor raised about using animals for testing, are there

alternatives to using such testing? What are the main tests that use animals and

alternatives that would achieve similar results? There is a lot of controversy

about using animals to test cosmetics. Animal rights organizations feel that it

is unnecessary and uncalled for. The Food and Drug Administration have no law

that cosmetics have to be tested on animals. The main reason cosmetic companies

continue to use animals to test their products instead of the alternatives is

because they are afraid of getting laws suites. The alternatives to animal

testing have not yet been validated, therefore if they were taken to court they

may not win the case if these alternatives were used. If companies would

recognize the consistency and validity of these products then maybe animal

testing will not be needed. Two of the main tests that companies use are the

Draize Test and the Irritancy Test. These tests are not needed because there are

other tests that don’t use animals and give the same if not better results. The

Draize Test is used to measure the harmfulness of the ingredients that are in

cosmetics and household products. The test involves dripping the substance into

a rabbit’s eye and recording the results. Scientists use rabbits because they

have large eyes and no tear ducts to wash away the chemical. Reactions vary from

slight irritation to ulceration and complete blindness. The rabbits are

restrained to keep from clawing their eyes. All of the animals are usually

killed 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 Medical

Research, the Draize Test should not be used because there are a number of

differences between the human eye and the rabbit eye. Rabbits have a third

eyelid, they have less tear fluid to wash away irritants, they have a more

alkaline eye (humans have a pH of 7.1-7.3, rabbits have a pH of 8.2), and

rabbits have a thinner cornea. Overall the Draize Test overestimates how

irritating a product is to the human eye because rabbits eyes are more sensitive

than the human eye (Freeberg). This test is also invalid because of the

differences in the way the damage is evaluated. In a study performed by Carnegie

University of Pittsburgh twelve substances were sent to twenty-four different

laboratories. The results that came back for the same substances ranged from

mild to severe reactions. Since the test itself is so unreliable companies

should look into some alternatives. An alternative to using animals to test how

harmful an ingredient is to the eye is a method called Eytex. Eytex uses a

vegetable protein taken from jack beans. This clear protein gel turns clear when

it comes in contact with irritating substances. This process is more accurate

than the Draize Test is because the "damage" is measured by a

spectrophotometer and not estimated by a person. The Eytex Test agrees well with

the Draize Test, although the results should be compared to human eye

irritation. Until better methods come along this test could be used instead of

animals. Here are some comparisons of the Eytex Test to the Draize Test: %

Agreement %Irritants Substances 85% 89% 101 80% 100% 465 The second column shows

how closely related Eytex results agreed with Draize Test results, the third

column shows what percentage of irritants were identified by Eytex, and the last

column shows the number of substances were tested. There is also close agreement

between laboratories on the results. One study showed 90% agreement between six

different laboratories and ten substances (Kelly). Another study sent sixty

substances to twelve different laboratories. In nine of thirteen categories of

substances there was 100% agreement between the laboratories. There was 83%-93%

agreement between the other four categories (Kelly). This shows that there is

more 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 the

Skin Irritancy Test. This test measures how a substance irritates the skin.

Patches are shaved off the backs of rabbits and slightly abraded to make them

more sensitive. The substance is placed on the bare skin and covered with gauze

for four hours. Researchers look for signs of redness, inflammation, weeping or

scabs (Animal Liberation). These tests have been shown to be invalid. In one

study household products were tested on rabbits, guinea pigs and humans. Only

four of the substances were non-irritating to all of the subjects. Twelve were

more irritating in one or more of the species and three were less irritating in

one or both of the animals than in humans (Nixon). In another study twelve

substances were tested on human and rabbit skin, the results were similar only

for the two most irritating substances. The remaining ten were irritating to the

rabbits but not the humans (Phillips). This shows that rabbits’ skin is also

more sensitive than humans. There are a number of alternatives to this test.

They include reconstructed human epidermis, the Microphisometer, and computer

modeling. Reconstructed human epidermis is a multi-layered human skin grown in

the laboratory and can be used to test skin irritancy. There are different ways

to measure the damage an irritating substance causes. Cells can be examined

under a microscope, membrane damage can be assessed by leakage of enzymes, or

inflammation can be determined by release of interleukins (Animal Liberation).

Whichever method is used, the results can be measured accurately, unlike the

skin irritancy tests done on animals where observers estimate the degree of

swelling or redness. Results from this test have so far agreed well with animal

studies, although ideally they should be compared to human information (Ponec).

The microphysiometer is an instrument that detects small changes in the pH of

the 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 the

metabolic rate of human skin by 50% there was very good agreement with animal

tests as shown in the table below (Parce). Chemical Animal Irritancy

Microphysiometer 1 mild 0.1 2 mild 0.5 3 moderate-mild 0.7 4 moderate-mild 0.8 5

moderate-mild 0.9 6 moderate 1.7 7 severe-moderate 3.9 8 severe 4.1 The table

shows that the Microphysiometer test rated the irritancy of the eight chemicals

in the same order as the animal tests, with the same kind of increase. The final

alternative to using animals for skin irritancy testing is computer modeling.

Expert computer systems are used to predict the irritancy of new substances

based on what is already known about substances with a similar chemical

structure. This approach is called Quantitative Structure-Activity Relationship.

(Animal Liberation). This system is very reliable. A New York company called

Health Designs shows that computer modeling distinguished severe irritants from

others 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 and

cures for many diseases, but in the case of household products and cosmetics

animals are not needed. There are many alternatives that are being used, and

should be used by all companies. Steps need to be taken to validate these

alternatives so cosmetic companies will have no dought about using these

alternative methods instead of using animals. Steps can be taken toward ending

animal testing for cosmetics by refusing to buy anything that was tested on

animals and writing to the companies insisting that they end the testing. No one

person can do it alone, but together as a whole it can come to an end.

Sharp 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 for

household products", Journal of Toxicology – Cutaneous Toxicology, 184, vol

1 (53-64) Philips L, Steinberg M, Maibach H & Akars W, "A comparison of

rabbit and human skin response to certain irritants", Toxicology and

applied Pharmacology, 1972, vol 21 (369-382) Nixon G, Tyson C & Wertz W,

"Interspecies comparisons of skin irritancy", Toxicology and applied

Pharmacology, 1975, vol 31 (481-490) Kelly C, "An in vitro method of

predicting ocular safety", Drug and Cosmetic Industry, September 1988

(54-64) Ponce M, "Reconstructed human epidermis in vitro: an alternative to

animal testing", Alta, 1995, vol 23 (97-110) Internet All for Animals,

Animal Testing alternatives, accessed Nov. 8, 1998 http://www.allforanimals.com/alternatives1.htm

Physician’s Committee for Responsible Medicine, Are There Valid Research

Methods, published: spring 1997, accessed Nov. 23, 1998 http://www.werple.net.au/antiviv/valid.htm

Animal Liberation, Product Testing, published: May 23,1998, accessed: Nov. 23,

1998 http://www.animalliberation.org.au/skineye.html