| 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
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