Better Science

Better Science


Replacing the use of animals in experiments

Despite the widespread belief that animal experimentation is necessary for medical progress, new and expanding technologies are making the use of animals in science obsolete.

The concept of animal testing as “a necessary evil” continues to thrive, in large part due to ignorance, fear, and the efforts of pro-vivisection organizations. The necessity of animals in research is a myth perpetuated by industries with strong vested financial interests in animal use as well as by scientists committed to the status quo, despite its limitations and dangers, as long as research dollars continue to support it.

Animal experiments actually can be of no use and even harmful to human health. They have produced misleading information that has resulted in dangerous treatments and drugs for humans, taken research efforts in wrong directions that wasted precious time and held back important medical advances for humans because of different results in animals, and have caused immense suffering in humans from faulty conclusions.

Today a large and growing area of cutting-edge research—“alternatives”—comprises methods that do not use animals. Alternatives lead to more accurate, predictive information for humans, expedite research findings, and save millions of animals countless suffering.

Brief overview of available alternatives

Epidemiological Research examines health and illness trends in actual human populations. Scientists study specific populations to examine factors that contribute to the causes and progression of a particular disease. By examining trends in wellness or illness, epidemiologists can identify factors that influence the onset of disease, such as lifestyle, heredity, and exposure. Epidemiological studies also contribute to our understanding of health and longevity.

Epidemiological research has led to better understanding of many human diseases including some of the leading killers of Americans today. For example, epidemiological studies showed the link between smoking and lung cancer, and between chemical exposures and birth defects. (1) AIDS was also first identified through epidemiological studies when rare infections and illnesses began showing up in patients in the late 1970s. (2)

Probably the most prominent epidemiological study is the Framingham Heart Study which has followed three generations of Americans in the town of Framingham, Massachusetts to study the effects of such things as diet, smoking, and exercise on cardiovascular health. Started in 1948, the Framingham study has been responsible for elucidating many key elements of heart disease, stroke and other illnesses. This study has been responsible for much of our present knowledge on such things as the role of exercise in reducing heart disease, the relationship between high cholesterol and the risk of stroke, the clinical course of rheumatic heart disease, complications of diabetes, and the role of psychosocial factors in heart disease. (3)

Epidemiological research puts humans at the center of the research. Such research is neither harmful nor intrusive to its human subjects, yet leads to the most applicable, reliable, and predictable understanding of human health and disease. Simply stated, it is the scientific method that underscores the truism that “the proper study of mankind is man.”

Tissue and Cell Research (often referred to as in vitro, meaning “in glass”) is conducted on living cells or tissue in a container such as a test tube or Petri dish, instead of on a living organism. By conducting such research on cell, tissue, and organ cultures, researchers have been able to learn with great accuracy about such things as the effectiveness and toxicity of medications and other products. 

One example involves the use of human cell and tissue cultures to predict the toxicity of substances in the human body. It replaces the use of living animals in a test called the Lethal Dose 50 (LD50), in which animals are force-fed increasingly large doses of a suspected toxic substance until 50% of them die. Many consider th test among the cruelest uses of living animals, in which animals suffer the hideous effects of slow poisoning. Despite its prevalence, the LD50 has only about a 60-66% accuracy rate in predicting how that same substance will react in humans. Scientists from around the world, in several different laboratories, have now developed in vitro methods, which can predict the effects of toxic substances in humans with a 77-83% accuracy rate. (4)

In vitro testing is also less time-consuming than animal testing. For example, screening plates can produce precise information for as many as 100,000 compounds a day. (5) This would take years to accomplish using animal tests. Based on the high efficacy of non-animal tests, the National Cancer Institute (NCI) switched in 1990 from using mice to screen potential anti-cancer drugs to a series of human cancer cell lines. This switch has had tremendous economic benefits and produces more rapid and more reliable results. (6)

Jarrod Bailey, PhD, a geneticist and Science Director for Project R&R and co-authors have studied the dangers and ineffectiveness of using other species to test for toxicity in relation to fetal development in humans. Read the abstract of The Future of Teratology Research is In Vitro.

Post-Marketing Drug Surveillance (PMDS) is used to track and report the outcomes and side effects of a medication once a drug is released to the public. Unfortunately, PMDS is not used consistently enough to reap its full benefits for human health—including preventing many human tragedies. (7) 

For example, if drugs such as DES, Fenfen, Vioxx, and thalidomide had been tracked using PMDS, a great deal of human lives and suffering would have been spared. More stringent monitoring of PMDS would help to reduce the large numbers of dangerous and lethal side effects that are known to occur from many drugs.

Experts estimate that 100,000 people die each year from adverse drug reactions that are the result of taking correctly prescribed medication. That number does not include the numbers who become ill from taking medications that have been prescribed incorrectly. Deaths due to adverse drug reactions rank sixth in the U.S. (8)

The U.S. Food and Drug Administration (FDA) has been harshly criticized by authorities for lacking a proper system to track and monitor adverse drug reactions. The current system for reporting drug reactions is based on voluntary compliance from doctors and many do not follow up due to time and other constraints. Experts estimate that the number of adverse drug reports received by the FDA each year represents only 3 to 10 percent of the true number. (9)

Post-marketing drug surveillance can also provide extremely useful information about the many drugs that produce therapeutic “side effects” that are unanticipated and occur in addition to the effects for which they were intended. For example, beta-blockers were originally intended to treat irregular heartbeats (and still are). Using PMDS, doctors noticed that these medications also lowered blood pressure and relieved angina and headaches. (10) As a result, beta-blockers are now prescribed for these health problems as well.

Clinical research is the study of humans who are undergoing treatment or receiving medication for a particular illness. It examines their responses to these treatments and medicines. For example, using a new technique called microdosing, human volunteers are given minute doses of an experimental drug that are too small to have any negative health effects on the body. The physiological effects of the drug are then observed using high-tech mass spectrometry equipment that reveals intricate functioning on the cellular level. Microdosing has provided a way for doctors to investigate drugs directly in the human system and early in the clinical trial process, while eliminating the risk of dangerous side effects. (11) This and other non-harmful methods are now available to study disease and treatments in humans, the only valid research model for human health.

Clinical research examines human subjects in their day-to-day lives and investigates the effects of certain medications or treatments. While typically participants are volunteers, some clinical studies report on observations that did not arise as part of a formal study but rather from physicians’ own reviews of their cases—looking for patterns, common variables to all patients, or unusual situations that are unexpected and therefore yield new information about the illness or treatment. Strict guidelines exist to protect volunteers participating in clinical research studies, including full disclosure of the nature of the study and the ability to withdraw from the study at any time. (12)

Many advances in medicine have come about through clinical studies. It was through clinical trials that drugs to treat AIDS and HIV (including AZT) were recognized as effective. (13) Clinical studies have also shown that lowering cholesterol through diet, drugs, or both prevented later heart attacks. (14) 

Autopsies are physical examinations performed upon cadavers. Used for centuries, they have enabled the discovery and further understanding of virtually every human disease. (15) Vast amounts of information about the progression of a disease can be learned from autopsy (a post-mortem examination of a dead animal is referred to as a necropsy). Autopsies can also help teach medical students operating techniques, such as fracture fixation, ligament reconstruction, and other procedures.

Live, anesthetized dogs are used to teach various surgical techniques or to demonstrate certain physiological reactions. According to PCRM, out of 154 U.S. medical schools, none use dogs in their live animal labs. And approximately 95 percent of them have eliminated live animal labs altogether.

Medical students who learn the procedures from hands-on experience on human cadavers have considerably more accurate information to use when applying operating techniques in a real-life situation. (16) (17)

Technology has led to numerous medical advancements. Sophisticated instrumentation and equipment continue to be developed, offering high-quality care and more accurate diagnoses. As a diagnostic tool, technology has been invaluable to monitor the progression of diseases and responses to treatment, as well as in revealing how the human body works.

Examples include ultrasound, blood-gas analysis machines, blood chemistry analysis machines, arterial catheters, lasers, molecular tweezers, anesthesia machines, computer-based equipment, pacemakers, bone and joint replacements, staplers, laparoscopic surgery, x-ray crystallography, synchrotron radiation, neutron sources, nuclear magnetic resonance, and other spectroscopies such as CAT scans and PET scans. (18)

Today’s modern scanning measures involve little or no pain or risk of complications and yield highly accurate results. Such technologies provide a window into the functioning of the human body without causing any harm or suffering to other animals.

Mathematical and computer models rely on sophisticated software to simulate biochemical reactions based on mathematical predictive models to determine how drugs work in the body. They can also be used to simulate human disease states to examine new therapies and drugs using computer simulation. (19) 

Mathematical and computer models are powerful research tools and, according to Americans for Medical Advancement, have already resulted in a wide range of new treatments that include “breast cancer treatments, high blood pressure medicines, prosthesis development, and new information regarding epilepsy.” (20) Mathematical and computer models are also increasingly used in veterinary and medical training.

Microbiological studies involve simple, non-sentient organisms such as bacteria, viruses, and fungi that are well-suited for screening large numbers of toxins and irritants. These studies also reveal basic cell properties. Since these substances can reproduce quickly, they are more cost effective.


Ending the use of chimpanzees in research was not a call to substitute other species for the areas of research in which they were used. Today, growing scientific evidence regarding the limitations and dangers of using a nonhuman species—even one, the chimpanzee, who shares 96 percent of our DNA—argues for the complete replacement of all species with modern non-animal alternatives.

Many areas of research have already committed to replacing all animal use with scientifically better alternative methods. Examples include the use of modern in vitro methods to replace the testing of caustic chemicals and the production of monoclonal antibodies, both procedures that are known to cause great pain when done on live animals.

As invaluable sources of information about human health and disease, alternative methods such as clinical and in vitro research, epidemiological studies and other alternatives must receive prioritized federal research funding.

Nonhuman animals are often used as the result of habit. Add to that lobbying efforts by biological supply companies for whom large sales of animals account for large shares of profits, and the reasons for the resistance to change from animal-based science to more progressive, effective, and efficient non-animal alternatives begin to become more clear.

As research institutions and companies supplying animals find ways to function and profit from alternatives, the animal model’s ethical and scientific limitations and dangers will become part of mainstream scientific thought.

Ethical and scientific arguments put forth by the animal protection community and caring scientists who have taken a stand against the status quo in research are bolstered by growing proof of both the inhumane suffering as well as the scientific limitations and dangers to humans of the animal model. All three—the ethical, scientific, and economic—arguments against the use of animals will one day lead to better and more humane science.

For more information


(1) Physicians Committee for Responsible Medicine, Fact Sheet on Animals in Research.

(2) Greek, R and Greek JS, 2000, “Effective or not? Animal models of AIDS” Satya, March 2000, page 18.

(3) Data from Framingham Research Volunteers Going to Genetic Study, Feb. 7, 2006,

(4) The MEIC Program, NICEATM, (CC Tox Consulting.)

(5) Altassets: The Alternative Assets newsletter, “High-throughput screening for new drugs.”

(6) Chabner, B. 1990. “In defense of cell-line screening” Journal of the National Cancer Institute, July 4. 82;13:1083-1085.

(7) United States Department of Health and Human Services, Agency for Healthcare Research and Quality, “Postmarketing drug surveillance could be improved.”

 (8) Weiss, R. 1998. Correctly Prescribed Drugs Take Heavy Toll, The Washington Post, page A1, April 15.

(9) FDA Cut Off Critic’s Access to Drug Safety Database, Chicago Tribune, Thu, 24 Feb 2005, web retrieved at Alliance for Human Research Protection.

(10) Greek, CR and Greek, JS. Sacred Cows and Golden Geese: The human cost of experiments on animals. 2000. Continuum, New York. page 168.

(11) Human microdosing proves its value in drug R&D, August 3, 2005,

(12) National Institutes of Health, Office of Human Subjects Research, Regulations and Ethical Guidelines.

(13) Greek, R and Greek JS, 2000, “Effective or not? Animal models of AIDS” Satya, March 2000, page 18.

(14) Greek, CR and Greek JS, 2004, What will we do if we don’t experiment on animals? Medical Research for the Twenty first century. Trafford publishers, Victoria, Canada. page 108.

(15) Ibid. p. 118.

(16) Physicians Committee for Responsible Medicine: FAQ Animal Use in Medical School Education.

(17) Physicians Committee for Responsible Medicine: Ethics in Trauma Training  go to

(18) Americans For Medical Advancement: Alternatives to Animal Experimentation: Technology.

(19) Christensen, D. In silico medicine: computer simulations aid drug development and medical care Science News, December 14, 2002.

(20) Americans For Medical Advancement: Alternatives to Animal Experimentation: Computer and Mathematical Modeling.

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