Advanced Placement Laureate Candidate
Collier County Public Schools
22 February 2010
Animal Testing: Cruel or Necessary?
Animal testing is a part of everyday life. From the shampoos and conditioners that consumers buy to medicines that patients receive, many everyday products are tested on animals. Why animal testing? To ensure the safety of the products? To reassure the consumers that what they’re buying won’t hurt them? Or do companies test on animals to ensure their products are “safe” just for a profit? Although animal testing has been effective in the past, such as in creating a vaccine for polio, the anatomical and physiological differences between humans and animals along with the recent advancement to modern cellular biology and recent discovery in tissue regeneration has led to the outdated usage of animal testing.
Animal testing has been present in our lives for centuries. Hippocrates was a physician from the fifth century BC. He knew that the only way to cure a disease would be to track its progression over time. The only way to do this was to watch patients. This method is called clinical observation and it is the most accurate method used today. Hippocrates is known as the “father of medicine” (Greek). Galen was another physician who helped pave the way in modern medicine. Sixteenth century Italian scientist, Galen, was inspired by Hippocrates. Banned from doing autopsies by the Church of Rome, he became known as the “father of vivisection”. Vivisection can be referred to the experimentation on animals; alternately it can mean “cut up the living.” When human autopsies were allowed again for research, many of Galen’s theories were proven wrong. Galen had used monkeys and other animals in his experiments. William Harvey, who earned a degree from Cambridge University, actually proved many of Galen’s theories wrong when the use of human autopsies was allowed again. For instance, a group of nerves exists in the back of a certain species of monkey’s brain. Galen had assumed that this also existed in humans. But, he was wrong, because no such nerves exist in humans, even though it was thought that that particular species of monkey was the closest “relative” to the human species (Greek). Harvey also discovered that blood flowed through the body by the pumping of the heart. He discovered that the blood travels through the heart, goes around the whole body, and then comes back to the heart just to be recirculated again.
Animals must endure many types of tests in order for companies to allow their products to reach consumers. Many tests are performed on these animals. Eye Irritancy Test, Acute Toxicity Test, and the LD50 test are all used on animals.
One of the many tests an animal might have to experience is the Eye Irritancy Test. Rabbits are normally used for this test, but other animals may be used as well. The rabbit would first be placed in a neck restraint, this way only its head would be sticking out. The animal is placed in the restraint so they are not able to scratch at their eyes or interfere with the testing. Then whether the chemical is in liquid form or in solid form, the chemical is placed in the animals’ eye. Also, their eyelids are normally held open by a clip so the rabbit cannot flush the chemical out of its eye. The animal is observed anywhere from “seventy two hours to eighteen days”; by then the animals are usually blind, but their eyes might be bleeding or swollen. In some cases the rabbits will break their necks in the restraints because they are trying to get out and they die (People for the Ethical Treatment of Animals).
Another test that is used on animals is the Acute Toxicity Test or the Poisoning Test. This test determines how much of a certain chemical will kill an animal. Scientists will insert the chemical into the veins, stomach, nasal cavities, and other organs. Reactions to this test vary from bleeding from the mouth, eyes, or nose, to break outs, or strenuous breathing. The scientists then look at the results to conclude whether or not the chemical is safe for human exposure (People for the Ethical Treatment of Animals).
The LD50 test, or the Lethal Dose 50 test, is another test that is given to animals. A certain dosage of the chemical is distributed to the animal. The test will continue until at least fifty percent of the animals in the experiment die. Then, the scientists look at the dosage amount of the chemical given to the animals and they “know” that that amount is “dangerous” for humans to either ingest or be exposed to (People for the Ethical Treatment of Animals).
Animal testing has many disadvantages that make it a poor choice to test products on. Some of these disadvantages include not the same species, drugs have different effects in humans and animals, dosages are given to animals in amounts that no human would ever take, and testing on animals takes more time than using a computer generated model.
When animals get sick, scientists don’t spend their time testing on humans to try and find a cure, they test on the same species. It also doesn’t make sense then that scientists test on animals to find cures for human illnesses. For a model to be a good test subject, it should have four predictable elements: the same neurobiological mechanisms, the same symptoms, the same treatment responses, and the same assumed origin of disease (Greek). Animals may be able to have a couple of these elements, but they will never have all four. Also, although animals may have many of the same organs as humans do, they do not function in the same manner. Veterinarian Dr. Margaret Wissman, who graduated from the University of Illinois, College of Veterinary Medicine wrote, “Interestingly, if for some reason, the rabbit is restrained tightly around the neck for any length of time (as for ear cleaning, grooming, etc.), it can cause the eyeball to swell and protrude, due to occlusion (cutting off) the blood supply to the external jugular vein, which is the primary venous drainage of the eye and head (unlike other animals, where the major drainage is via the internal jugular vein, which is harder to compress due to its deeper location).” Because the rabbit’s eye may swell, this is distorting all of the research the scientists are trying to find by administering tests to the rabbits. Also, because of the unique structure of the animals’ stomach, they cannot vomit like humans. So, in the case of humans, their body would try to get rid of any unwanted chemical in their body and their body may try to do this by vomiting. Well, rabbits cannot do this, so already the experiment is biased on the fact that the two species’ stomachs are constructed differently.
Some drugs administered to humans have been very successful, but the same drug may not be successful in animals. Penicillin is used to cure infections in many humans, but when tested on guinea pigs, the guinea pigs died. Another common drug, Aspirin, used commonly to reduce minor pains in humans, killed cats when it was being tested on them (Burgos). So if scientists would’ve seriously considered this data, humans might not have the luxury of these drugs available to them.
Drugs have been very successful for animals, but harmful for humans. Opren, a drug for arthritis, was tested on monkeys and no negative side effects were found. When brought to the market for humans, sixty one people were killed and over three thousand five hundred documents were reported with people having severe side effects. Rats were given the drug Primacor, or Milrinone, and it worked fine in rats, but when given to humans, it increased the death rate by thirty percent. Primacor was used to assist hearts that don’t pump enough blood throughout the body. The drug, Domperidone, created to reduce nausea and vomiting, was given to humans and it created irregular heartbeats. But, scientists tried to get this side effect in animals, but they were unsuccessful, even at doses several times the amount given to humans. Nomifensine, an antidepressant drug, was linked to anemia, kidney and liver failure, and death in humans. But, animals were fine after given the drug (Greek).
When animals are given the chemicals, they are given the chemical in higher dosages than humans would ever be exposed to. The artificial sweetner, Cyclamate, was given to animals. The sweetener is already around “thirty to fifty” times sweeter than sugar, but the animals were given the equivalent of five hundred and fifty two bottles of soda in one day. No human drinks that much soda in one day, so already the experiment data was exaggerated. Rats were given the product, Trichloroethylene, which is used in the process of coffee decaffeination. The rats were given an equivalent of fifty million cups of coffee in one day. Again, humans don’t drink fifty million cups of coffee in one day, so this data is also going to be unreliable (Fano).
Testing on animals takes more time than computer generated models. This is one reason why scientists should switch to computer generated model research. Animals may take weeks to test on and get results that they can use, while using a computer generated model may only take minutes to find the results, without having to subject the animal through all the stressful experiments and getting skewed data. Also, the scientists would be able to produce scientific documents and papers quicker if they could get less biased data that doesn’t take as long to find (Hayhurst). By using a computer generated model, the scientist can look at a model of the stomach and place a certain chemical in it to see how it will react.
Animal testing has kept scientists from advancing human medicine and knowledge in the areas of diabetes, cancer, AIDS, and vaccines.
Diabetes ruins the body’s abilities deliver glucose where glucose is needed. Glucose is a simple sugar in which our digestive system breaks apart food into glucose. Insulin is produced in the pancreas and it normally moves the glucose throughout the bloodstream. Certain cells, like the muscle and fat cell, have insulin receptors and the insulin hormone attaches to the receptors and it therefore initiates a chemical reaction where the glucose is then allowed to go into the cell. This doesn’t occur in diabetics. The blood carries the glucose to the cells, but without the insulin, the cells reject the glucose. Scientists decided to use animals in the research and better understanding of diabetes. But, this kept them off the right path for many years. Because of the animal research that was conducted, it was not believed that the pancreas was involved in diabetes or that insulin even existed. One scientist, Charles Best, who graduated from the University of Toronto, administered dog insulin to a boy that was 14 years old, but the results were horrible. The blood glucose level did go down a mere 25%, which is barely anything, but with horrible side effects (Greek).
Deaths from cancer
have been increasing since 1973 and experimenting
Non-humans do not get AIDS. Scientists must place a similar disease in the animal in order to test on them. Millions of dollars a year are being wasted on animal testing with AIDS. People infected with AIDS should be angry at this knowing animals can’t get the disease. Scientists have only learned how different the immune systems work in animals and humans by doing this research. Researchers learned more about this disease by in vitro research. No one knows exactly where AIDS and HIV came from, but there is one theory. The theory is that someone came in close contact with a monkey whether being near it or eating it and the person got the simian (primate) virus. This virus then mutated inside the human and became the disease we know today, AIDS. Scientists tried to give HIV to primates by injecting them with the disease, but nothing has happened yet (Greek 181-204).
When World War II came around, the need for vaccines and antibiotics was at its’ height. Pharmaceutical companies felt the pressures of developing new drugs and sending them out. They put the drugs through animal tests and if the animals didn’t die or have serious illnesses, then the scientists would put the drug through human trials. But, the human trials weren’t long enough to get substantial data for conclusive results. Thalidomide was released in the 1950s to pregnant mothers to reduce morning sickness. It had passed all the animal experimentations, so everyone assumed it was safe to consume. But, mothers started giving birth to babies with deformities like undeveloped limbs, which didn’t show up in animal test results. So scientists knew that this side affect was prevalent in humans, so they gave more of the drug to animals and nothing happened to the animal’s young. The White New Zealand rabbit finally produced some results the scientists were hoping for. The offspring were affected by the drug Thalidomide, but only at a dosage between 25 and 300 times that humans were given (Greek).
How often does animal testing occur? Well there are many “professions” that incorporate animal testing into their companies. Some jobs where animal testing occurs are in the military, with psychologists, and for consumer product producers.
The military’s use of animal experimentation is not in the human interest as many people argue. Monkeys are used by the United States Air Force. The monkey is first tied down to a “Primate Equilibrium Platform (PEP).” The monkey is given electric shocks until it knows to hold the control stick that is in front of it. The platform is then slanted forward and shocks are given until the monkey learns to pull the stick back. At first, the platform isn’t controlled by the monkey moving the stick, it is controlled by the scientists, but later on in the experiment that ability is given to the monkey. The monkey must learn to keep the platform level. This takes about ten to twelve days to ensure the monkey knows how to keep the platform level. Then the monkey is given a dose of radiation or a dose of “chemical warfare agent, like Soman gas.” The monkey is then placed back on the platform and is suppose to keep the platform steady while nauseated and possibly vomiting. But this type of information is invaluable during war because a war general isn’t going to look through records of animal experiments to see whether or not his officers could stand a second attack on the enemy or not. The general will look at the situation at hand and see what their chances of winning are (Rowlands 130-131). The US Army experiments on dogs, especially Beagles. TNT is fed to the dogs. The symptoms the dogs show: anemia, low body temperature, diarrhea, dehydration, emaciation, and death. It is also known that the military officials don’t go through the data received by the animal experiments. Testing on animals is considered “Top Secret”, so many people don’t know much about it. People only know what has been published by the military, which hasn’t been much (Rowlands 131-132).
Psychologists have also been known to experiment on animals. Psychologists constantly test on animals. Psychologists use “shuttleboxes” to test on animals, like dogs. A “shuttlebox” is a box with two compartments separated by a barrier. The floor of the box is a grid that administers shocks when the animal is placed on one side; this causes the animal to jump to the other side of the box, but then more shocks are administered, so the animal jumps back and forth between the compartments. Then the psychologists replace the barrier with a piece of glass, which the animal will run into when a shock is administered to it. Eventually, the animal is exhausted and lies on the floor of the box, still being shocked. This experiment is supposed to show that depression can be learned. Even though this test has been redone for the past thirty years, the researchers are still undecided about what this can show humans (Rowlands 132-133). H. Harlow, a famous psychologist, experimented on monkeys. He wanted to see how social isolation affected the monkeys. There were a variety of experiments conducted. One experiment was to take the baby away from its mother a few hours after birth and put it into isolation for the first few months of life, sometimes longer. Or, the baby might be put with a “cloth mother” that would rock violently or eject spikes from its body periodically. Or, a monkey might be raised in isolation and then made pregnant, by a device. Some of the mothers ignored their babies when born. Other mothers would crush in their babies’ skull with their teeth. This isn’t helpful to humans, especially since “maternal deprivation” and isolation was documented well before these experiments took place (Rowlands 134-135).
Animal experimentation is probably more commonly known for its role in “commercial product-testing.” All types of items are tested on animals; the most well-known are probably beauty products. If a company wanted to release a new shampoo, they would most likely perform the Draize test, or eye irritancy tests, on a rabbit. Are these tests vital to the well being of human beings? No, because humans don’t need that new shampoo, eye shadow, or laundry detergent (Rowlands 126-128). Plus, many of the same ingredients are used over and over again in new products, so why continue to test them on animals?
With every con to a topic there is always going to be a pro, otherwise it wouldn’t be a topic worth discussing. A couple of advantages to animal testing exist, alternatives are limited and new in the making, animals take less time to test on than humans, and with in vitro research scientists can’t determine all the side effects.
One of the advantages to testing on animals is the fact that alternatives are limited and new in the making. Scientists have been using animals to test on for centuries, while some of the alternatives that have come around are new in the making and scientists can not yet determine whether or not they will be helpful to the people.
Another advantage to testing on animals is the fact that testing on animals takes less time. In order to have a successful test on a human, the scientist would have to have all the original subjects in the experiment from the beginning to the end. Well, this might not be the case, the human subject might not want to go back for testing after the first round or they might do something that could alter the outcome of the experiment. At least with animals the animals will always be in their cages in the laboratory. Also, the animals don’t have a choice of whether or not they want to return, they must stay until the end of the experiment or until they die. If the scientist were to question the human subject to try and get the side effects of the drug from them or if they felt better, the scientist may ask a leading question to where they’re hinting at the response they want. This will not make the results of the experiment accurate. Also, the researcher wouldn’t be able to have complete control over the human subjects like they do with the animals. When the researchers work with the animals they can make sure all the animals are given the same amount of food, water, and that they are all living in the same environment. When humans are used, they would go home after the experiment and eat whatever foods they’re use to and drink whatever beverage they want. Well, the type of food or drink the human consumes could have an effect on the medicine they’re taking. But, the researchers wouldn’t know this, because even if the researchers give the humans a strict diet to follow, they most likely won’t abide by the diet regulations, further messing up the data.
If scientists were to use in vitro instead of animals to experiment with, scientists would not be able to tell the effects of the medicine on the body as a whole, they would only be able to tell the effects the medicine had with that type of cell or whatever the scientists were testing it on. Also, the scientist wouldn’t be able to tell the mental state of the patient when using in vitro research, so there would be no way of determining whether or not the medicine could cause depression or anxiety.
Many alternatives are available for scientists to use instead of experimenting on animals. Some of these alternatives include test tube research, clinical observation, observing autopsies, epidemiology, and computer generated models.
The first type of alternative available is test tube research, or commonly known as in vitro research. Researchers place the culture in the test tube and then place chemicals in the test tube with the culture. They observe the reactions that take place and record them. If the cells divide rapidly or mutate rapidly by the chemical, researchers then know that that may be causing the disease in humans. When the chemical disturbs the action of the disease, the chemical may therefore be a cure for the disease (Greek 99-101).
Another alternative to animal testing is clinical observation. The best way to see how a disease works in a human is to watch people with that disease and see how they progress over time. By being able to observe humans and the side effects of certain drugs or procedures, scientists can get the most out of the experiment since it directly relates to humans (Pippin). Clinical observations have been one of the most useful tools in curing cancer. During World War I, doctors noticed that soldiers exposed to mustard gas had low white blood cell counts. They figured a mustard gas derivative would help cancers like lymphoma and leukemia because in these cancers, the white blood cells are overproduced. Because of animal experiments, many researchers believed folic acid would help patients with cancer. When tried with humans, disaster was the only thing scientists saw. Scientists then decided that they should try “methotrexate” which inhibits folic acid; they skipped animal testing and gave it to children with leukemia. This is a widely used method in helping children with leukemia. Most agents that have assisted in the success of children with cancer have come from non-animal methods of discovering a cure (Greek 137-141).
Autopsies are another method available to scientists. Autopsies have helped in the research of Alzheimer’s disease, heart disease, and diabetes. With autopsies, researchers are able to look at the entire body and see how the disease spread through the body and how it affected it (Pippin).
Epidemiology is also another method that can be used instead of animal testing. Gathering data about illnesses present among certain populations may lead to valuable information about how and why a specific illness occurs. This method would NOT be used for finding a cure to a disease, but it can be used to help assist scientists in research (Pippin).
Another alternative that was mentioned briefly before is the use of computer generated models. Scientists now have interactive software that can have them work with specific organs of the human body. They may also see how certain chemicals will affect the organ and the rest of the body. This is better for research because the scientist doesn’t have to wait around to see the side effects in a human or an animal. Also, the computer generated model wouldn’t be stressed out by being experimented on, so the results will be more helpful to the human race. (Hayhurst).
Genetic research is the last available method that scientists are able to use. Doing research on certain genes will show who is susceptible to what disease and how that person might react to a type of therapy. This method is much more effective than animal testing, because this shows what an individual needs in order to get well again.
In conclusion, based on scientific achievement, animal testing is no longer a necessity in advancements for consumer products. Although animal testing has been effective in the past, such as in creating a vaccine for polio, the anatomical and physiological differences between humans and animals, the recent advancement to modern cellular biology, and recent discovery in tissue regeneration has led to the outdated usage of animal testing. Scientists should be pushing for alternatives to animal testing more than they are, since the purpose of them being in medicine is to save lives. Medical advancements can only continue if scientists use more up-to-date ways of finding cures or medications. Scientists, companies, and government officials should listen to the words of Robert M. Freedman, Chairman and Chief Executive Officer of Hurel Corporation, with a SB Degree from MIT and Masters’ Degrees from Harvard Business School and the Kennedy School of Government at Harvard, “If we're smart enough to go to the moon, then we should be smart enough to test chemicals without hurting other creatures."
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