safe animal experiments

Animal testing and experiments FAQ

How many animals are used in experiments each year?

Which animals are used in experiments, what kinds of experiments are animals used in, what kinds of institutions use animals in experiments, where do laboratories get the animals they use in experiments, what is life like for animals in laboratories, what happens to the animals once an experiment is over, aren’t there laws to protect animals used in experiments, why are animals still used in experiments, what are the alternatives to experiments on animals, what are the advantages of using non-animal alternatives instead of animals in experiments.

• What are you doing to end experiments on animals?

What can I do to help animals in laboratories?

Stand with us to demand that the federal government, state governments, companies and universities stop relying on outdated animal experiments.

It is estimated that more than 50 million animals are used in experiments each year in the United States. Unfortunately, no accurate figures are available to determine precisely how many animals are used in experiments in the U.S. or worldwide.

The U.S. Department of Agriculture (USDA) does compile annual statistics on some animals used in experiments, including cats , dogs , guinea pigs , hamsters , pigs , primates , rabbits and  sheep .

However, the animals most commonly used in experiments—“purpose-bred” mice and rats  (mice and rats bred specifically to be used in experiments)—are not counted in annual USDA statistics and are not afforded the minimal protections provided by the Animal Welfare Act. The Animal Welfare Act is a federal law that sets minimal standards for the treatment of certain warm-blooded animals used in experiments. The law also requires that unannounced inspections of all regulated animal testing facilities are carried out annually, although some facilities only receive partial inspections . In addition to purpose-bred mice and rats, animals such as crabs, fish , frogs, octopuses and turtles , as well as purpose-bred birds , are not covered by the Animal Welfare Act. The failure to protect these animals under the law means that there is no oversight or scrutiny of their treatment in the laboratory or the experiments performed on them. And, because these animals are not counted, no one knows how many of them are suffering in laboratories. It also means that facilities using unprotected species in experiments are not required to search for alternative, non-animal methods that could be used to replace or reduce harmful experiments that use animals.

View Animals Used in Experiments by State

View Dogs Used in Experiments by State

Read Dogs Used in Experiments FAQ

Use our Animal Laboratory Search Tool  to find information about universities, hospitals, companies and other organizations that use certain animals in experiments

View a list of U.S. laboratories that use certain animals in experiments ; click on “License Type” and select “Class R – Research Facilities." Note that numbers only include animals covered by the Animal Welfare Act.

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Animals used in experiments include baboons, cats , cows , dogs , ferrets,  fish , frogs, guinea pigs , hamsters , horses , llamas, mice , monkeys (such as marmosets and macaques), owls, pigs , quail, rabbits , rats and  sheep .

Chimpanzees have thankfully not been subjected to invasive experiments in the U.S. since 2015, when federal decisions were made to prevent their use. Despite this, hundreds of chimpanzees are still languishing in laboratories while they wait to be moved to sanctuaries.

Animals are used in many different kinds of experiments. These are just a few examples:

• Dogs have their hearts, lungs or kidneys deliberately damaged or removed to study how experimental substances might affect human organ function.  
• Monkeys are taken from their mothers as infants to study how extreme stress might affect human behavior.
• Mice are force-fed daily doses of a chemical for two years to see if it might cause cancer in humans.
• Cats have their spinal cords damaged and are forced to run on treadmills to study how nerve activity might affect human limb movement.
• Ferrets are deliberately infected with extremely painful, potentially fatal diseases (such as RSV, COVID-19 or Ebola) and not given pain relief or treatment before their death to study how humans might be affected by the same disease.  
• Pigs are implanted with various devices (such as pacemakers and dental implants) to study how human bodies might respond to such devices.  
• Pregnant rabbits are force-fed toxic pesticides every day for several weeks to study how human mothers and babies might be affected if they were exposed to the pesticides.
• Sheep are subjected to high pressures (such as those experienced deep underwater) for hours at a time and then returned to normal pressure so that their response can be observed.
• Rats are placed in small tubes and are forced to inhale cigarette smoke for hours at a time to study how humans might respond to cigarette smoke.   
• Baboons are injected with endometrial tissue to induce painful symptoms of endometriosis and study how humans might be affected by the disorder.
• Horses are infected with a potentially fatal virus (such as hepatitis) and their symptoms monitored to study how humans might be affected by the same virus.

Experiments are often excruciatingly painful for the animals used and can vary in duration from days to months to years. The experiment can cause vomiting, diarrhea, irritation, rashes, bleeding, loss of appetite, weight loss, convulsions, respiratory distress, salivation, paralysis, lethargy, bleeding, organ abnormalities, tumors, heart failure, liver disease, cancer and death.

There is no limit to the extent of pain and suffering that can be inflicted on animals during experiments. In some instances, animals are not given any kind of pain medication to help relieve their suffering or distress during or after the experiment on the basis that it could affect the experiment.

Animals are typically killed once an experiment is over so that their tissues and organs can be examined, although it is not unusual for animals to be used in multiple experiments over many years. There are no accurate statistics available on how many animals are killed in laboratories every year.

Read Cosmetics Animal Testing FAQ

• Read about our 2022 undercover investigation at Indiana laboratory Inotiv, one of America’s largest animal testing labs. We documented hundreds of dogs, monkeys, rats and pigs undergoing experiments, including terrified beagle puppies being force-fed a potentially toxic drug in cruel and ineffective months-long tests paid for by Crinetics, a pharmaceutical company in San Diego.
• Read about our 2019 undercover investigation at a Michigan laboratory where thousands of dogs are killed every year. After weeks of pressure from the public, the pesticide company that had commissioned a year-long fungicide test on 32 dogs agreed that the test was unnecessary and released the dogs to one of our shelter partners to be adopted.

Chemical, pesticide and drug companies (as well as contract laboratories that carry out tests for those companies), public and private universities, community and technical schools, government facilities, Veterans Affairs (VA) facilities and hospitals all use animals in experiments.

View USDA List of Organizations that Use Dogs in Experiments

View Chart of Institutions That Use Dogs in Experiments

The majority of animals in laboratories are “purpose-bred” meaning that they are bred specifically to be used in experiments. People who breed and sell certain purpose-bred animals are called Class A dealers and are licensed and inspected by the U.S. Department of Agriculture (USDA). Facilities that only sell purpose-bred mice, rats, birds or cold-blooded animals such as crabs, fish, frogs, octopuses and turtles to laboratories are excluded and are not licensed or inspected by the USDA.

Some animals used in experiments are taken from the wild—including birds and  monkeys . 

Historically, some cats and dogs  were sold to laboratories by brokers known as random source Class B dealers, who acquired animals at auctions, from newspaper ads and various other sources, including animal shelters. Random source Class B dealers have not been allowed to operate since 2015 when Congress first passed legislation to prevent them from being licensed.  

Some cats and dogs in laboratories are still obtained directly from animal shelters, a practice known as “pound seizure.” Pound seizure laws vary from state to state with one state (Oklahoma) requiring shelters to give cats and dogs to laboratories, rather than euthanizing them, and others allowing or prohibiting laboratories from taking animals from animal shelters. Some states have no laws at all, leaving it up to the individual shelter or locality.

View Pound Seizure Laws by State

Animals in laboratories suffer immensely. In addition to the painful experiments that the vast majority of animals in laboratories experience over days, months, years or even decades, life in a laboratory is typically a miserable and terrifying experience.

Typically kept alone in barren steel cages with little room to move around and few, if any, comforts, such as toys or soft bedding, animals often become excruciatingly lonelyand anxious, often devoid of the companionship of other animals or the loving touch of a human. Animals in laboratories can associate humans with painful situations and, with no way to hide or get away, they panic whenever a person approaches their cage or freeze with fear when they are taken into treatment rooms. Despite this, dogswill often still seek out human attention.

Animals in laboratories typically also have to watch (or hear) other animals suffering, including their own parents, siblings or babies. High levels of constant stress can cause animals to exhibit unnatural behaviors. For example, it is not uncommon for monkeys to mutilate themselves or to rock or vocalize constantly as a way to help relieve their anxiety, mice to overgroom each other until they are completely bald, and dogs to continually pace.  

Very often the experiments themselves lead to suffering and death. In our 2022 undercover investigation we documented monkeys in “restraint chairs”—devices that are used to hold monkeys in place while the experiments are carried out—who accidentally hanged themselves while unattended. We also documented a dog named Riley used to test a substance so toxic that it brought him near death after only two days of forced dosing. He was hypersalivating, trembling, vomiting, and moaning, yet was dosed yet again with this highly toxic substance. Later, he lay on the floor, unable to stand. Our undercover investigator tried to comfort him while he was dying, but Riley was left to suffer in excruciating pain overnight because the laboratory’s veterinarian was unavailable on a weekend

Animals in laboratories are also subject to mistreatment by inexperienced or careless staff. Although there are penalties for laboratories when animals are injured or killed due to negligence or when they fail to meet minimum standards of animal care, in reality, the fines are typically either very small or waived entirely.

In some cases, animals die as a deliberate result of the experiment. For example, the LD50 (lethal dose 50%) test, which is typically performed on mice, rats, pigeons, quail and fish, involves determining the dose of a substance (such as a pesticide) that kills (or would lead to the death of) 50% of the animals tested.

It is extremely rare that animals are either adopted out or placed into a sanctuary after research is conducted on them. However, more and more states are passing laws that require laboratories, when possible, to offer dogs and cats to shelters and other rescue organizations so they can be adopted into loving homes after the experiments they were used in have ended. As of December 2023, 16 states have such laws.

The Animal Welfare Act was designed to protect certain animals, like dogs and monkeys, used in experiments, but the law only offers minimal standards for housing, food and exercise. The Animal Welfare Act also stipulates that the proposed experiments be reviewed by an Institutional Animal Care and Use Committee, whose members are appointed by the laboratory itself and largely made up of employees of the institution. A 2014 audit report reviewing Animal Welfare Act oversight of laboratories found that “animals are not always receiving basic humane care and treatment and, in some cases, pain and distress are not minimized during and after experimental procedures.”

The animals most commonly used in experiments—“purpose-bred” mice and rats  (mice and rats bred specifically to be used in experiments)—are not counted in annual USDA statistics and are not afforded the minimal protections provided under the Animal Welfare Act. The Animal Welfare Act is a federal law that sets minimal standards for the treatment of certain warm-blooded animals used in experiments. The law also requires that unannounced inspections of all regulated research facilities are carried out annually. In addition to purpose-bred mice and rats, animals such as crabs, fish , frogs, octopuses and turtles as well as purpose-bred birds are not covered by the Animal Welfare Act. The failure to protect these animals under the law means that there is no oversight or scrutiny of their treatment and use in the laboratory. And, because these animals are not counted, no one knows how many of them are suffering in laboratories. It also means that facilities using unprotected species in experiments are not required to search for alternative, non-animal methods that could be used to replace or reduce harmful experiments that use animals.

The vast majority of experiments on animals are not required by government law or regulations. Despite that, government agencies often seem to prefer that companies carry out animal tests to assess the toxicity or efficacy of products such as industrial chemicals, pesticides, medical devices and medicines.

For example, the Environmental Protection Agency (EPA) requires that a new pesticide be fed to dogs for 90 days as part of its evaluation and approval process. The Food and Drug Administration (FDA), which regulates various products such as drugs, medical devices, food, fragrances and color additives, will not approve potential drugs unless they are first tested on animals, which usually includes dogs. In addition to tests on  dogs ,  mice and rats ,  rabbits ,  birds  and primates are also used to test pesticides and drugs. These types of tests have been performed for years, regardless of whether they provide valuable information. While some regulatory agencies, like the EPA, are now taking a critical look at these animal tests to determine if they provide information necessary for assessing how safe a product or substance is for humans, and if better approaches are available, others have done little. More efforts can be made by agencies to invest in and encourage the development of non-animal methods.

Swapping animal experiments for non-animal alternative methods seems like a straightforward process, given that using animals has so many limitations and sophisticated new technologies offer countless possibilities for creating methods that are more humane and that more accurately mimic how the human body will respond to drugs, chemicals or treatments. Unfortunately, developing these alternatives is a complex process facing many obstacles, including inadequate funding. In most cases, a non-animal alternative must be formally validated—historically an expensive and lengthy process—in order to be accepted by government regulatory agencies, both in the U.S. and globally, although new, faster approaches to approving these methods are being developed. In contrast, animal experiments have never been subjected to the same level of scrutiny and validation. Despite these challenges, many scientists are increasingly committed to developing and using non-animal methods.

The world is continuously moving toward a future dominated by sophisticated methods that use human cells, tissues and organs, 3D printing, robotics, computer models and other technologies to create experiments that do not rely on animals.

While many animal experiments have not changed since they were developed decades ago and will always have severe limitations, advanced non-animal methods represent the very latest techniques that science has to offer, provide countless possibilities to improve our understanding and treatment of human diseases and will only continue to improve over time. Non-animal methods also have several advantages over outdated animal experiments: they more closely mimic how the human body responds to drugs, chemicals and treatments; they are more efficient and often less expensive; and they are more humane. Ultimately, moving away from animal experiments is better for both humans and animals.

We advocate for the immediate replacement of animal experiments with available non-animal methods and for more funding to develop new non-animal methods. A concerted effort to shift funding and technological development toward more non-animal alternatives will lead us to a future where animal experiments are a thing of the past.

Examples of non-animal alternative methods

• “Organs-on-chips” are tiny 3D chips created from human cells that look and function like miniature human organs. Organs-on-chips are used to determine how human systems respond to different drugs or chemicals and to find out exactly what happens during infection or disease. Several organs, representing heart, liver, lungs or kidneys, for example, can be linked together through a “microfluidic” circulatory system to create an integrated “human-on-a-chip” model that lets researchers assess multi-organ responses.
• Sophisticated computer models use existing information (instead of carrying out more animal tests) to predict how a medicine or chemical, such as drain cleaner or lawn fertilizer, might affect a human.
• Cells from a cancer patient’s tumor are used to test different drugs and dosages to get exactly the right treatment for that specific individual, rather than testing the drugs on animals.
• Specialized computers use human cells to print 3D tissues that are used to test drugs.
• Skin cells from patients, such as those with Alzheimer’s disease, are turned into other types of cells (brain, heart, lung, etc.) in the laboratory and used to test new treatments.
• Sophisticated computer programming, combined with 3D imaging, is used to develop highly accurate 3D models of human organs, such as the heart. Researchers then input real-world data from healthy people and those with heart disease to make the model hearts “beat” and test how they might respond to new drugs.

Human cells or synthetic alternatives can replace horseshoe crab blood in tests to determine whether bacterial contaminants are present in vaccines or injectable drugs.

• Animal experiments are time-consuming and expensive.
• Animal experiments don’t accurately mimic how the human body and human diseases respond to drugs, chemicals or treatments.
• Animals are very different from humans and, therefore, react differently.
• Increasing numbers of people find animal testing unethical.
• There are many diseases that humans get that animals do not.

What are you doing to end experiments on animals?

We advocate for replacing animals with non-animal alternative methods when they are available and more funding for the development of new alternative methods to quickly replace antiquated and unreliable animal tests and experiments. Our two main areas of focus are ending cosmetics animal testing  and ending experiments on dogs .

Cosmetics testing on animals

We—along with our partner, Humane Society International —are committed to ending cosmetics animal testing forever. Through our  Be Cruelty-Free campaign, we are working in the United States and around the globe to create a world where animals no longer have to suffer to produce lipstick and shampoo. 

• In the United States, we are working to pass the Humane Cosmetics Act , federal legislation that would prohibit animal testing for cosmetics, as well as the sale of animal-tested cosmetics.
• We are also working in several U.S. states to pass legislation that would end cosmetics animal testing. As of March 2024, 12 states (California, Hawai'i, Illinois, Louisiana, Maine, Maryland, Nevada, New Jersey, New York, Oregon, Virginia and Washington) have passed laws banning the sale of animal-tested cosmetics.
• Internationally, as of December 2023, 45 countries have passed laws or regulations to ban cosmetics animal testing, including every country in the European Union, Australia, Brazil, Canada, Chile, Colombia, Ecuador, Guatemala, Iceland, India, Israel, Mexico, New Zealand, Norway, South Korea, Switzerland, Taiwan, Turkey, the United Kingdom.
• We work with scientists from universities, private companies and government agencies around the globe to promote the development, use and regulatory acceptance of non-animal test methods that will reach beyond cosmetics.
• We educate consumers about animals used in cruel and unnecessary cosmetics tests and how to shop for cruelty-free cosmetics and personal care products.

Experiments on dogs

There is no place for harmful experiments on dogs in the U.S. We are committed to ending this practice.

• In the summer of 2022, we led the removal of 3,776 beagles from Envigo, a facility in Virginia that bred dogs to sell to animal laboratories. This historic mission was the result of a lawsuit filed by the U.S. Department of Justice that described shocking violations of the Animal Welfare Act at the facility. Instead of continuing to suffer, the dogs were removed from Envigo and headed to loving homes , a process facilitated by our shelter and rescue partners around the country.
• In April 2022, we released the results of our undercover investigation at Inotiv, an Indiana laboratory where thousands of dogs, monkeys, pigs and rats are used in experiments and killed.
• In 2021, we released a report examining the U.S. government’s role in using dogs in experiments. We found that the government uses millions of taxpayer dollars to fund harmful experiments on dogs each year—and also seems to prefer that companies carry out dog tests. Our researchers scrutinized public records and found that between 2015 and 2019, the National Institutes of Health (NIH) awarded more than $200 million to 200 institutions for 303 projects that used dogs in harmful experiments. Dogs were subjected to multiple surgeries, fitted with equipment to impair their heart function and implanted with devices to alter normal bodily functions. Following the conclusion of an experiment, dogs are typically killed instead of being adopted into loving homes.
• In 2019, we released the results of our undercover investigation at a Michigan laboratory where thousands of dogs are killed every year. After weeks of pressure from the public, the pesticide company that had commissioned a test year-long fungicide test on 32 dogs, agreed that the test was unnecessary and released the dogs to one of our shelter partners so they could be adopted.
• After a recent analysis we performed that showed the 90-day dog test for pesticide registration was rarely used by the Environmental Protection Agency (EPA) to assess the risk that pesticides pose to humans, we are urging the agency to eliminate or significantly limit this test in the near future. We also want the agency to reaffirm their previously stated commitment to end their reliance on using mammals to test pesticides and chemicals by 2035.
• We are asking the Food and Drug Administration (FDA) to support the development of alternative methods that replace dogs in experiments. 
• We want the Department of Veterans Affairs (VA) to adopt the recommendations of an independent panel review released in 2020 that analyzed VA experiments using dogs, identified several areas where dogs are not needed and urged the agency to develop a strategy to replace all animal use. 
• We are recommending that the National Institutes of Health (NIH) scrutinize grant proposals for projects using dogs, by applying strict criteria that must be met before dogs can be used and that they ban the use of dogs in experiments that cause unrelieved pain. We are also requesting that the NIH define a date when they will no longer fund or support experiments on dogs.
• prohibit or limit the use of dogs in experiments not required by federal law, similar to laws passed in California and Illinois .
• ensure an opportunity for  dogs and cats to be adopted into loving homes after the experiment ends.
• strengthen regulatory oversight of facilities that breed dogs destined for laboratories and increase penalties for animal welfare violations.
• Direct state funding to support the research and development of modern non-animal technologies, similar to the law passed in Maryland .

One easy way to help animals suffering in cosmetics tests is to swap out your personal care and household products for cruelty-free versions! Cosmetics (such as shampoo, deodorant and lipstick) and household products (such as dish soap, laundry detergent and glass cleaner) are typically tested on guinea pigs , rabbits ,  mice and rats .

Help us demand better for animals used in experiments through the following actions:

• Tell the FDA to stop encouraging companies to test on animals and instead switch to sophisticated non-animal alternatives.
• Stand with us to end research and tests on dogs by signing our petition.
• Urge the USDA to do their job and help protect animals in laboratories.
• Ask your federal legislators in Congress to ban cosmetic tests on animals.
• Support efforts to replace animal experiments with advanced non-animal alternatives that are better for both human health and animal welfare.

Follow us on Facebook to learn the latest news and actions related to animals in laboratories!

Alternatives to horseshoe crab blood

The Humane Society of the United States urges that horseshoe crab blood be replaced with non-animal methods when conducting endotoxin tests for medical products.

Vaccine, injectable drug and medical device manufacturers must test for endotoxins, a type of bacterial contaminant that, if present, can cause patients to develop symptoms that can include fever, chills, headache and nausea. Blood from horseshoe crabs is used to conduct the Limulus amebocyte lysate (or LAL) test for endotoxins.

The problem

To create this test, horseshoe crabs are captured from the wild and up to 30% of their blood is removed by medical supply companies. The crabs are later returned to the wild; however, it is estimated that 10-15% or more of them die as a result of this process.

In addition to being collected for their blood, horseshoe crabs are gathered up by fisheries, which use them as bait. These practices have led to a rapid decrease in the horseshoe crab population, putting them at risk of extinction. The decrease in wild horseshoe crab populations also impacts other species, including migratory shorebirds like the red knot, a threatened species that depends on horseshoe crab eggs for food.

THE solution

Scientists have developed recombinant Factor C (rFC), a synthetic alternative to the protein in horseshoe crab blood that can detect bacterial endotoxins. Repeated studies have demonstrated that rFC is equivalent or superior to the LAL test. A second method—the monocyte activation test—uses human cells and can not only detect bacterial endotoxins, but also pyrogenic (fever-causing) non-endotoxins.

what should be done

As a member of the Horseshoe Crab Recovery Coalition, the Humane Society of the United States is advocating for the replacement of the Limulus amebocyte lysate test with recombinant Factor C (rFC) or the monocyte activation test (MAT).

We urge the U.S. Pharmacopoeia—which sets quality, purity, strength and identity standards for medicines, food ingredients and dietary supplements—to encourage manufacturers to use rFC or MAT rather than LAL.

We also urge the U.S. Food and Drug Administration to update its guidance for vaccine, injectable drug and device manufacturers to indicate that these non-animal tests are now the preferred methods for endotoxin and pyrogenicity testing.

Please consider a generous gift to help spare dogs from life in a lab and give all animals a better life!

Should Animals Be Used for Scientific or Commercial Testing?

• History of Animal Testing

Animals are used to develop medical treatments, determine the toxicity of medications, check the safety of products destined for human use, and other  biomedical , commercial, and health care uses. Research on living animals has been practiced since at least 500 BC.

Descriptions of the dissection of live animals have been found in ancient Greek writings from as early as circa 500 BC. Physician-scientists such as  Aristotle ,  Herophilus , and  Erasistratus  performed the experiments to discover the functions of living organisms.  Vivisection  (dissection of a living organism) was practiced on human criminals in ancient Rome and Alexandria, but prohibitions against mutilation of the human body in ancient Greece led to a reliance on animal subjects. Aristotle believed that animals lacked intelligence, and so the notions of justice and injustice did not apply to them.  Theophrastus , a successor to Aristotle, disagreed, objecting to the vivisection of animals on the grounds that, like humans, they can feel pain, and causing pain to animals was an affront to the gods. Read more background…

Pro & Con Arguments

Pro 1 Animal testing contributes to life-saving cures and treatments for humans and animals alike. Nearly every medical breakthrough in the last 100 years has resulted directly from research using animals, according to the California Biomedical Research Association. To name just a few examples, animal research has contributed to major advances in treating conditions including breast cancer, brain injury, childhood leukemia, cystic fibrosis, multiple sclerosis, and tuberculosis. Testing on animals was also instrumental in the development of pacemakers, cardiac valve substitutes, and anesthetics. [ 9 ] [ 10 ] [ 11 ] [ 12 ] [ 13 ] Scientists racing to develop a vaccine for coronavirus during the 2020 global pandemic needed to test on genetically modified mice to ensure that the vaccine did not make the virus worse. Nikolai Petrovsky, professor in the College of Medicine and Public Health at Flinders University in Australia, said testing a coronavirus vaccine on animals is “absolutely essential” and skipping that step would be “fraught with difficulty and danger.” [ 119 ] [ 133 ] Researchers have to test extensively to prevent “vaccine enhancement,” a situation in which a vaccine actually makes the disease worse in some people. “The way you reduce that risk is first you show it does not occur in laboratory animals,” explains Peter Hotez, Dean for the National School of Tropical Medicine at Baylor College. [ 119 ] [ 141 ] Further, animals themselves benefit from the results of animal testing. Vaccines tested on animals have saved millions of animals that would otherwise have died from rabies, distemper, feline leukemia, infectious hepatitis virus, tetanus, anthrax, and canine parvo virus. Treatments for animals developed using animal testing also include pacemakers for heart disease and remedies for glaucoma and hip dysplasia. [ 9 ] [ 21 ] Animal testing has also been instrumental in saving endangered species from extinction, including the black-footed ferret, the California condor and the tamarins of Brazil. The American Veterinary Medical Association (AVMA) endorses animal testing to develop safe drugs, vaccines, and medical devices. [ 9 ] [ 13 ] [ 23 ] Read More

Pro 2 Animals are appropriate research subjects because they are similar to human beings in many ways. Chimpanzees share 99% of their DNA with humans, and mice are 98% genetically similar to humans. All mammals, including humans, are descended from common ancestors, and all have the same set of organs (heart, kidneys, lungs, etc.) that function in essentially the same way with the help of a bloodstream and central nervous system. Because animals and humans are so biologically similar, they are susceptible to many of the same conditions and illnesses, including heart disease, cancer, and diabetes. [ 9 ] [ 17 ] [ 18 ] Animals often make better research subjects than humans because of their shorter life cycles. Laboratory mice, for example, live for only two to three years, so researchers can study the effects of treatments or genetic manipulation over a whole lifespan, or across several generations, which would be infeasible using human subjects. Mice and rats are particularly well-suited to long-term cancer research, partly because of their short lifespans. [ 9 ] [ 29 ] [ 30 ] Further, animals must be used in cases when ethical considerations prevent the use of human subjects. When testing medicines for potential toxicity, the lives of human volunteers should not be put in danger unnecessarily. It would be unethical to perform invasive experimental procedures on human beings before the methods have been tested on animals, and some experiments involve genetic manipulation that would be unacceptable to impose on human subjects before animal testing. The World Medical Association Declaration of Helsinki states that human trials should be preceded by tests on animals. [ 19 ] [ 20 ] A poll of 3,748 scientists by the Pew Research Center found that 89% favored the use of animals in scientific research. The American Cancer Society, American Physiological Society, National Association for Biomedical Research, American Heart Association, and the Society of Toxicology all advocate the use of animals in scientific research. [ 36 ] [ 37 ] [ 38 ] [ 39 ] [ 40 ] [ 120 ] Read More

Pro 3 Animal research is highly regulated, with laws in place to protect animals from mistreatment. In addition to local and state laws and guidelines, animal research has been regulated by the federal Animal Welfare Act (AWA) since 1966. As well as stipulating minimum housing standards for research animals (enclosure size, temperature, access to clean food and water, and others), the AWA also requires regular inspections by veterinarians. [ 3 ] All proposals to use animals for research must be approved by an Institutional Animal Care and Use Committee (IACUC) set up by each research facility. Most major research institutions’ programs are voluntarily reviewed for humane practices by the Association for Assessment and Accreditation of Laboratory Animal Care International (AAALAC). [ 24 ] [ 25 ] Animal researchers treat animals humanely, both for the animals’ sake and to ensure reliable test results. Research animals are cared for by veterinarians, husbandry specialists, and animal health technicians to ensure their well-being and more accurate findings. Rachel Rubino, attending veterinarian and director of the animal facility at Cold Springs Harbor Laboratory, says, “Most people who work with research animals love those animals…. We want to give them the best lives possible, treat them humanely.” At Cedars-Sinai Medical Center’s animal research facility, dogs are given exercise breaks twice daily to socialize with their caretakers and other dogs, and a “toy rotation program” provides opportunities for play. [ 28 ] [ 32 ] Read More

Con 1 Animal testing is cruel and inhumane. Animals used in experiments are commonly subjected to force feeding, food and water deprivation, the infliction of burns and other wounds to study the healing process, the infliction of pain to study its effects and remedies, and “killing by carbon dioxide asphyxiation, neck-breaking, decapitation, or other means,” according to Humane Society International. The US Department of Agriculture reported in Jan. 2020 that research facilities used over 300,000 animals in activities involving pain in just one year. [ 47 ] [ 102 ] Plus, most experiments involving animals are flawed, wasting the lives of the animal subjects. A peer-reviewed study found serious flaws in the majority of publicly funded US and UK animal studies using rodents and primates: “only 59% of the studies stated the hypothesis or objective of the study and the number and characteristics of the animals used.” A 2017 study found further flaws in animal studies, including “incorrect data interpretation, unforeseen technical issues, incorrectly constituted (or absent) control groups, selective data reporting, inadequate or varying software systems, and blatant fraud.” [ 64 ] [ 128 ] Only 5% of animals used in experiments are protected by US law. The Animal Welfare Act (AWA) does not apply to rats, mice, fish, and birds, which account for 95% of the animals used in research. The types of animals covered by the AWA account for fewer than one million animals used in research facilities each year, which leaves around 25 million other animals without protection from mistreatment. The US Department of Agriculture, which inspects facilities for AWA compliance, compiles annual statistics on animal testing but they only include data on the small percentage of animals subject to the Act. [ 1 ] [ 2 ] [ 26 ] [ 28 ] [ 135 ] Even the animals protected by the AWA are mistreated. Violations of the Animal Welfare Act at the federally funded New Iberia Research Center (NIRC) in Louisiana included maltreatment of primates who were suffering such severe psychological stress that they engaged in self-mutilation, infant primates awake and alert during painful experiments, and chimpanzees being intimidated and shot with a dart gun. [ 68 ] Read More

Con 2 Animal tests do not reliably predict results in human beings. 94% of drugs that pass animal tests fail in human clinical trials. Over 100 stroke drugs and over 85 HIV vaccines failed in humans after succeeding in animal trials. Nearly 150 clinical trials (human tests) of treatments to reduce inflammation in critically ill patients have been undertaken, and all of them failed, despite being successful in animal tests. [ 57 ] [ 58 ] [ 59 ] Drugs that pass animal tests are not necessarily safe. The 1950s sleeping pill thalidomide, which caused 10,000 babies to be born with severe deformities, was tested on animals prior to its commercial release. Later tests on pregnant mice, rats, guinea pigs, cats, and hamsters did not result in birth defects unless the drug was administered at extremely high doses. Animal tests on the arthritis drug Vioxx showed that it had a protective effect on the hearts of mice, yet the drug went on to cause more than 27,000 heart attacks and sudden cardiac deaths before being pulled from the market. [ 5 ] [ 55 ] [ 56 ] [ 109 ] [ 110 ] Plus, animal tests may mislead researchers into ignoring potential cures and treatments. Some chemicals that are ineffective on (or harmful to) animals prove valuable when used by humans. Aspirin, for example, is dangerous for some animal species. Intravenous vitamin C has shown to be effective in treating sepsis in humans, but makes no difference to mice. Fk-506 (tacrolimus), used to lower the risk of organ transplant rejection, was “almost shelved” because of animal test results, according to neurologist Aysha Akhtar. A report on Slate.com stated that a “source of human suffering may be the dozens of promising drugs that get shelved when they cause problems in animals that may not be relevant for humans.” [ 105 ] [ 106 ] [ 127 ] Read More

Con 3 Alternative testing methods now exist that can replace the need for animals. Other research methods such as in vitro testing (tests done on human cells or tissue in a petri dish) offer opportunities to reduce or replace animal testing. Technological advancements in 3D printing allow the possibility for tissue bioprinting: a French company is working to bioprint a liver that can test the toxicity of a drug. Artificial human skin, such as the commercially available products EpiDerm and ThinCert, can be made from sheets of human skin cells grown in test tubes or plastic wells and may produce more useful results than testing chemicals on animal skin. [ 15 ] [ 16 ] [ 50 ] [ 51 ] Michael Bachelor, Senior Scientist and Product Manager at biotech company MatTek, stated, “We can now create a model from human skin cells — keratinocytes — and produce normal skin or even a model that mimics a skin disease like psoriasis. Or we can use human pigment-producing cells — melanocytes — to create a pigmented skin model that is similar to human skin from different ethnicities. You can’t do that on a mouse or a rabbit.” The Environmental Protection Agency is so confident in alternatives that the agency intends to reduce chemical testing on mammals 30% by 2025 and end it altogether by 2035. [ 61 ] [ 134 ] [ 140 ] Scientists are also able to test vaccines on humans volunteers. Unlike animals used for research, humans are able to give consent to be used in testing and are a viable option when the need arises. The COVID-19 (coronavirus) global pandemic demonstrated that researchers can skip animal testing and go straight to observing how vaccines work in humans. One company working on a COVID-19 vaccine, Moderna Therapeutics, worked on developing a vaccine using new technology: instead of being based on a weakened form of the virus, it was developed using a synthetic copy of the COVID-19 genetic code. [ 142 ] [ 143 ] Read More

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Ethical care for research animals

WHY ANIMAL RESEARCH?

The use of animals in some forms of biomedical research remains essential to the discovery of the causes, diagnoses, and treatment of disease and suffering in humans and in animals., stanford shares the public's concern for laboratory research animals..

Many people have questions about animal testing ethics and the animal testing debate. We take our responsibility for the ethical treatment of animals in medical research very seriously. At Stanford, we emphasize that the humane care of laboratory animals is essential, both ethically and scientifically.  Poor animal care is not good science. If animals are not well-treated, the science and knowledge they produce is not trustworthy and cannot be replicated, an important hallmark of the scientific method .

There are several reasons why the use of animals is critical for biomedical research: 

••  Animals are biologically very similar to humans. In fact, mice share more than 98% DNA with us!

••  Animals are susceptible to many of the same health problems as humans – cancer, diabetes, heart disease, etc.

••  With a shorter life cycle than humans, animal models can be studied throughout their whole life span and across several generations, a critical element in understanding how a disease processes and how it interacts with a whole, living biological system.

The ethics of animal experimentation

Nothing so far has been discovered that can be a substitute for the complex functions of a living, breathing, whole-organ system with pulmonary and circulatory structures like those in humans. Until such a discovery, animals must continue to play a critical role in helping researchers test potential new drugs and medical treatments for effectiveness and safety, and in identifying any undesired or dangerous side effects, such as infertility, birth defects, liver damage, toxicity, or cancer-causing potential.

U.S. federal laws require that non-human animal research occur to show the safety and efficacy of new treatments before any human research will be allowed to be conducted.  Not only do we humans benefit from this research and testing, but hundreds of drugs and treatments developed for human use are now routinely used in veterinary clinics as well, helping animals live longer, healthier lives.

It is important to stress that 95% of all animals necessary for biomedical research in the United States are rodents – rats and mice especially bred for laboratory use – and that animals are only one part of the larger process of biomedical research.

Our researchers are strong supporters of animal welfare and view their work with animals in biomedical research as a privilege.

Stanford researchers are obligated to ensure the well-being of all animals in their care..

Stanford researchers are obligated to ensure the well-being of animals in their care, in strict adherence to the highest standards, and in accordance with federal and state laws, regulatory guidelines, and humane principles. They are also obligated to continuously update their animal-care practices based on the newest information and findings in the fields of laboratory animal care and husbandry.  

Researchers requesting use of animal models at Stanford must have their research proposals reviewed by a federally mandated committee that includes two independent community members.  It is only with this committee’s approval that research can begin. We at Stanford are dedicated to refining, reducing, and replacing animals in research whenever possible, and to using alternative methods (cell and tissue cultures, computer simulations, etc.) instead of or before animal studies are ever conducted.

Organizations and Resources

There are many outreach and advocacy organizations in the field of biomedical research.

• Learn more about outreach and advocacy organizations

Stanford Discoveries

What are the benefits of using animals in research? Stanford researchers have made many important human and animal life-saving discoveries through their work. 

• Learn more about research discoveries at Stanford

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• Published: 29 September 2004

Use of animals in experimental research: an ethical dilemma?

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Gene Therapy volume  11 ,  pages S64–S66 ( 2004 ) Cite this article

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Mankind has been using animals already for a long time for food, for transport and as companion. The use of animals in experimental research parallels the development of medicine, which had its roots in ancient Greece (Aristotle, Hippocrate). With the Cartesian philosophy in the 17th century, experiments on animals could be performed without great moral problems. The discovery of anaesthetics and Darwin's publication on the Origin of Species, defending the biological similarities between man and animal, contributed to the increase of animal experimentation. The increasing demand for high standard animal models together with a critical view on the use of animals led to the development of Laboratory Animal Science in the 1950s with Russell and Burch's three R's of Replacement, Reduction and Refinement as guiding principles, a field that can be defined as a multidisciplinary branch of science, contributing to the quality of animal experiments and to the welfare of laboratory animals. The increased interest in and concern about animal welfare issues led to legislative regulations in many countries and the establishment of animal ethics committees.

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Van Zutphen LFM . History of animal use. In: Van Zutphen LFM, Baumans V, Beynen AC (eds). Principles of Laboratory Animal Science . Elsevier: Amsterdam, 2001, pp 2–5.

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Dennis Jr MB . Welfare issues of genetically modified animals. ILAR J 2002; 43 : 100–109.

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Russell WMS, Burch RL . The Principles of Humane Experimental Technique . Methuen: London, 1959, Reprinted by UFAW, 1992: 8 Hamilton Close, South Mimms, Potters Bar, Herts EN6 3QD England.

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Baumans, V. Use of animals in experimental research: an ethical dilemma?. Gene Ther 11 (Suppl 1), S64–S66 (2004). https://doi.org/10.1038/sj.gt.3302371

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Imagine a syringe being forced down your throat to inject a chemical into your stomach, or being restrained and forced to breathe sickening vapours for hours. That’s the cruel reality of animal testing for millions of mice, rabbits, dogs and other animals worldwide.

Animals killed for every new pesticide chemical tested

Beagles in government-required tests for each new drug or agrochemical

Agreement required between countries to eliminate a single animal test

Did you know that animal testing is legally required for many of the products we use every day? From fragrances to painkillers to the fabric dyes in our clothing, every new chemical has at one time been force-fed to animals. HSI is working around the globe in cooperation with companies and government authorities to replace cruel and obsolete animal-poisoning tests with modern alternatives that better protect human and environmental safety.

Animal testing facts:

• Government regulations often require numerous different animal-poisoning tests to assess the hazards of a single new chemical, pesticide or medicinal product.
• Some tests use thousands of animals at a time, while others are repeated two or even three times using different animal species or routes of administration (oral force-feeding, forced inhalation or skin); no pain relief is provided.
• There’s no “humane” way to poison animals with chemicals or to infect them with deadly diseases like rabies to test the effectiveness of a vaccine; however, there are modern non-animal alternatives that work just as well—or better.
• HSI works through intergovernmental bodies such as the OECD to accelerate global adoption of modern non-animal testing methods, and through our network of country offices to have these new approaches taken up through national regulations.
• Our efforts have been instrumental in securing “mandatory alternatives” requirements in Brazil and South Korea, whereby it is illegal for a company to conduct animal experimentation if a non-animal approach is available.
• Amendments to the Canadian Environmental Protection Act now include measures to phase out the use of animals for chemical toxicity testing and require new approach testing methods be prioritized when available.
• We’re also helping pass bans on cosmetic animal testing around the world through our #BeCrueltyFree campaign.
• HSI is supporting training in developing countries to help companies and government authorities transition to modern non-animal methods.

Our work in action

Over 300 south korean academic and industry experts urge the passage of bills promoting better science without the use of animals.

“There is an increasing interest in using modern technologies that are more predictive of human responses than animal models.” -Borami Seo, HSI/Korea

EU Commission backs phase-out of animal use in experiments and chemicals tests but ignores citizens’ wishes on cosmetics

“The Commission ignored citizens’ calls to uphold the ban on animal testing for cosmetics; a ban established by legislators over a decade ago.” -Aviva Vetter, HSI’s senior manager for cosmetics

New statistics reveal record-high animal use in South Korean laboratories, nearing 5 million in 2022

“This report shows that Korean bio-science is stuck in the past, heavily relying on animal testing despite new human mimetic methodologies emerging without animal use.” -HSI/Korea’s director of government affairs, Borami Seo

Victory! Canadian Government passes provisions to phase out the use of animals in chemical toxicity testing

“A concerted move away from animal-based toxicity tests could spare tens of thousands of animals each year and advance public health and environmental protection with more advanced and relevant tests for the benefit of all Canadians.” -Shaarika Sarasija, senior strategist, research and regulatory science for HSI/Canada

End Animal Testing European Citizens’ Initiative validated with over 1.2 million signatures

“No other ECI has ever received this level of support across so many different countries.” -Troy Seidle, vice president, Research & Toxicology, HSI

“HSI’s spokes-bunny Ralph has come to Europe with a message for governments that it’s time to hop to it and #EndAnimalTesting.” -Troy Seidle, HSI VP of research and toxicology

Pathways to a Better Future

“Science can help us avoid animal testing of chemicals and better protect ourselves and our environment.” -Troy Seidle, vice president, Research & Toxicology, HSI

Urge South Korea to shift research funding away from animal experiments

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1. sign the be cruelty-free pledge., 2. read to learn more., 3. join us on facebook., become an animal defender, discover more.

We’re giving the beauty industry a cruelty-free makeover with a wave of animal testing bans supported by hundreds of companies and millions of caring consumers worldwide.

We all dream of the day when cancer is cured and AIDS is eradicated, but is the continued use of mice, monkeys and other animals as experimental “models” of human disease actually holding us back from realizing the promise of 21st century science?

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Explainer: What Is Animal Testing?

Vaccines, medications and cosmetics rely on animal testing even though the process is cruel, unreliable and often inaccurate.

Explainer • Animal Testing • Policy

Words by Björn Ólafsson

The use of animals in experiments is so endemic that “guinea pig” is used as an alternative term for “test subject.” But underlying this ubiquity is a set of processes that harm animals unnecessarily: rats force-fed drugs designed to induce tumors, monkeys kept in tiny cages with chemicals irritating their skin and beagles euthanized without any anesthesia.

Critics say many of these experiments are unreliable and even unnecessary. Advocates for reduced animal testing earned a win in December 2022: the FDA announced that it would no longer require animal tests prior to approving a drug for human trials.

What Is Animal Testing?

Animal testing, sometimes called in vivo testing, is a process of determining if certain medications, vaccines and cosmetics are safe for humans by first experimenting with them on animals. Animal testing is common in most countries and has been used in some forms throughout much of human history.

Cosmetic Testing

Cosmetic testing is a process of using animals to test any cosmetic product before human use, such as makeups, lotions, creams, fragrances, oils or facial masks. 

Testing for Medicine

Medical testing involves using animals to examine new drugs, research biological systems, investigate genetic factors, delve into animal psychologies or test out surgical strategies. Nowadays, drugs are the most common form of medical testing on animals.  

The History of Animal Testing

Animal testing is a long-documented practice, with some of the oldest instances dating back to around 300 B.C. in ancient Greece. Yet while animal testing was widespread in the form of vivisection and practice for operations, it wasn’t until the 20th century that medicines were commonly tested on animals. In fact, several laws were passed in this period, including the 1938 Federal Food, Drug, and Cosmetic Act in the U.S., that encouraged or mandated the use of animals in testing before human consumption. 

What Types of Animals Are Used in Animal Testing?

Invertebrates.

Common invertebrates used in animal testing include fruit flies and nematode worms. Unfortunately for these animals, no federal protections exist to minimize their pain or suffering in the U.S.

Vertebrates

There’s truth in the common phrase “lab rat” — 95 percent of animals used in animal testing are mice or rats. Dogs, cats, pigs, monkeys, other primates, rabbits and sheep are all used in addition to rodents. 

How Many Animals Are Used in Experiments Each Year?

This is a difficult question to answer, because the U.S. Department of Agriculture only counts certain species of animals in its annual review of animal testing. Mice and rats specifically bred for testing purposes are not counted because they do not fall under the U.S. Animal Welfare Act.

However, it’s been estimated that at least 50 million animals are used in the U.S. every year. The real number is unknown and may be higher. Worldwide, exact numbers are unknown, but some estimate the number to be around 200 million experiments per year. 

What’s Wrong With Animal Testing?

Is animal testing painful.

Some researchers attempt to reduce the pain for animal test subjects, but many do not. According to the USDA animal usage summary report , roughly 8 percent of animals were experimented on with no measures taken to ensure pain reduction. This report does not take into account animals that do not fall under the Animal Welfare Act, so the real number is unknowable and likely much higher. 

Even animals protected by the Animal Welfare Act are often subjected to levels of pain that are hard to comprehend. Of all surgeries on animals, 40 percent do not report using anesthesia, and drugs are often force-fed to animals. Animals are also often killed after the experiments are completed, long before the end of their natural lifespan.  

Are Animal Testing Results Reliable?

Animal tests do not catch all possible side effects before drugs move to a later phase of testing. According to a 2004 report from the USDA, 92 percent of medicines that pass an animal testing phase will not proceed to market, and a major cause of this failure is safety problems that were not predicted by animal tests. More recent reports from scientists estimate an even higher number of 96 percent . 

There are a variety of reasons why animal tests are considered unreliable. According to a 2015 review in the Cambridge Quarterly of Healthcare Ethics , these include the effects of laboratory conditions; the different ways that diseases impact animals and humans; and the differences in physiology and genetics across species, all of which lead to inaccuracies. Due to such factors, a breakthrough meta-analysis published in Alternatives to Laboratory Animals in 2015 argued that a lack of toxicity of a drug in any of the five species most commonly used in animal testing — dogs, rats, mice, rabbits and monkeys — was not able to indicate the likelihood of a similar lack of toxicity in humans. In other words, animal tests don’t work. 

Advocates for animal testing often argue that the complexity of a living organism — the organs, circulatory system and genetic regulation — will affect drugs in a way that single tissue samples cannot. This argument fails to account for the fact that nonhuman systems are very different from human systems, which leads to inaccuracy. 

Animal testing can also lead to banning drugs that would benefit humans. For example, tamoxifen , a drug used to treat breast cancer, can cause tumors in rodents. If this drug had been tested on animals in early phases of research, it is likely the benefits of tamoxifen would have remained untapped. 

Is Animal Testing Cruel?

Due to the combination of low accuracy and high amounts of pain, it is difficult to argue that animal testing is not cruel. Animals such as rats, mice, dogs and chimpanzees are burned, poisoned, crippled, starved or abused in other ways via drugs, confinement or other invasive procedures.

Animals like these are sensitive to pain, emotionally empathetic and capable of forming social bonds. But to the researchers in charge of them, they are nothing more than tools. 

Is Animal Testing Archaic?

Due to the inaccuracy of animal testing, voices have arisen to criticize its outdated methodology. Not only is animal testing an old-fashioned practice that hasn’t been brought into the 21st century, but evidence shows it is likely holding back medical research. 

Is Animal Testing Wasteful?

Because of the inaccuracy of animal testing, many scientists and experts argue that its existence is inherently wasteful. British doctor Ian Roberts writes that “biased or imprecise results from animal experiments may result in clinical trials of biologically inert or even harmful substances, thus . . . wasting scarce research resources.”

Is Animal Testing Illegal?

Cosmetics testing has been banned in 42 countries and 10 U.S. states (California, Hawaii, Illinois, Maine, Maryland, Nevada, New Jersey, Louisiana, New York and Virginia). New York’s ban on cosmetic testing goes into effect in January 2023 , which makes it possible that more states will continue to follow their lead. 

No countries currently ban medical animal testing, but this may soon change. This year, Switzerland held a referendum on medical animal testing. A large Swiss pharmaceutical lobby campaigned against the initiative, which was ultimately unsuccessful. But the fact that animal testing went from untouchable fact to subject of a national debate sparks doubt about its continued acceptance in the future. 

Aren’t There Laws To Protect Animals Used in Experiments?

There do exist some laws to protect animals, such as the U.S. Animal Welfare Act. However, this law does very little to protect animals from pain, and doesn’t even count rats and mice as protected animals.

Cosmetic testing is far more controversial in the public sphere and therefore more heavily regulated. It is almost entirely banned in the European Union and other countries, including Guatemala, Colombia, India, Taiwan and the U.K. The U.S. has no federal cosmetics ban.

Why Are Animals Still Used in Experiments?

Despite the lack of sustained evidence for animal testing’s usefulness, and the possibility of cheaper alternatives (as discussed below), animal testing seems to be used far more often than it should be. Why?

First of all, the pharmaceutical industry has maintained a clear interest in preserving animal testing, and only very rarely review evidence about its actual usefulness. Another issue is scientific tradition and established practice. Scientists are likely to cite historical precedent as a reason for selecting an animal model, as opposed to the model’s similarity to human systems or effectiveness in predicting toxicity, according to a 2019 paper in Alternatives to Animal Experimentation . 

Should Animal Testing Be Banned?

Calls to ban animal testing because of its ineffectiveness and cruelty have been getting louder in recent years. Entire conferences are held to discuss alternatives to animal testing, and many petitions and campaigns are igniting across the world. These voices don’t just originate from the animal liberation movement, either. Prominent scientists , pharmaceutical bosses and concerned citizens are joining the chorus. 

Alternatives to Animal Testing

Thankfully, there exist several alternatives to animal testing, some of which have become more popular and common in recent years. 

In Vitro Testing

In vitro testing is a process of conducting an examination in a test tube using tissue samples.

Human Tissues

Real human tissue samples, which can be ethically donated to science as a result of surgeries or after death, are viable alternatives for testing localized drugs. For years, research has indicated that various in vitro methods can hypothetically outperform animal testing (and cost less too), although this form of testing is likely best used for understanding toxicity within a single organ or organ system, not the entire human body. 

A new human tissue testing method has emerged recently that shows promise. An in vitro skin testing model called h-CLAT recently entered use in Europe and Japan, paving the way for more techniques that don’t require animal experimentation. 

In Vitro Modeling Systems

Another form of in vitro testing involves a synthetic model that can replicate human systems. While less accurate, this method is cheaper and far easier to source, although it is best used for simpler human organs like the skin. One example, the EpiDerm technology , is already widespread for cosmetic purposes. This method is currently not used for large-scale medicinal approval, but instead to test if certain people are at risk for certain diseases. 

Computer Modeling 

Of all the alternatives, scientists are most excited about computer modeling techniques. Advanced computer modeling, sometimes called in silica testing, can create complex models of human body systems, even accounting for irregularities like prior diseases, as well as a vast array of genetic and demographic information. 

And they work better than animal models. A 2018 study found an accuracy rate of between 89 percent and 96 percent , while a 2017 study estimated the accuracy rate of one method of analysis at 96 percent : in both studies the computer models beat the animal testing experiments. 

Research Using Human Volunteers

Using human volunteers seems a bit dystopian, but science has progressed a long way since the unethical days of the 20th century. For starters, in some recent drug testing human volunteers only receive a microdose of the drug and are monitored in the presence of medical professionals to ensure safety. This microdosing method is promising, but still needs more research. Other forms of human volunteer research include the safe use of fMRI imaging, which has been shown to be very effective. 

Of course, ethics regarding human volunteers are critical. Scientists and researchers must take great caution not to compel participants into doing something unsafe and must mitigate risks as much as possible. Using human volunteers is also best done after one other method, like computer modeling, has been completed to mitigate risk. 

Animal Testing Facts and Statistics

• The majority of animals used in animal testing are exempt from the Animal Welfare Act because they are rats or mice.
• Rats have great memories and demonstrate empathy for other animals.
• Every year, the NIH spends nearly $20 billion on animal testing-based research.
• A majority of Americans disapprove of the continued use of animal testing.

What You Can Do

Consumers who want to avoid products tested on animals can look for a “vegan” or “cruelty-free” label when purchasing cosmetic products. They can also voice their support for policies to improve animal welfare in the medical industry like the FDA Modernization Act 2.0 , which passed the U.S. Senate earlier this year.

Independent Journalism Needs You

Björn Jóhann Ólafsson is a science writer and journalist who cares deeply about understanding the natural world and her inhabitants through stories and data. He reports on the environmental footprint of the meat industry, the alternative protein sector and cultural attitudes around food. His previous bylines include the EU Observer and Elemental. He lives in Spain with his two lovebirds.

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Arguments against animal testing

Animal experiments are cruel, unreliable, and even dangerous

The harmful use of animals in experiments is not only cruel but also often ineffective. Animals do not naturally get many of the diseases that humans do, such as major types of heart disease, many types of cancer, HIV, Parkinson’s disease or schizophrenia. Instead, signs of these diseases are artificially induced in animals in laboratories in an attempt to mimic the human disease. Yet, such experiments belittle the complexity of human conditions which are affected by wide-ranging variables such as genetics, socio-economic factors, deeply-rooted psychological issues and different personal experiences.

It is not surprising to find that treatments showing “promise” in animals rarely work in humans.  Not only are time, money and animals’ lives being wasted (with a huge amount of suffering), but effective treatments are being mistakenly discarded and harmful treatments are getting through. The support for animal testing is based largely on anecdote and is not backed up, we believe, by the scientific evidence that is out there.

Despite many decades of studying cancer, Alzheimer’s disease, Parkinson’s disease, diabetes, stroke and AIDS in animals, none of these conditions have reliable and fully effective cures and some don’t even have effective treatments.

The history of cancer research has been the history of curing cancer in the mouse. We have cured mice of cancer for decades and it simply didn’t work in human beings.

Unreliable animal testing

• 92% of drugs fail in human clinical trials despite appearing safe and effective in animal tests, often on safety grounds or because they do not work.
• Urology drugs have the lowest success rate (only 4% are approved after entering clinical trials) followed by heart drugs (5% success rate), cancer drugs (5% success rate) and neurology drugs (6% success rate).
• Our research has shown that using dogs, rats, mice and rabbits to test whether or not a drug will be safe for humans provides statistically little useful insight. Our study also revealed that drug tests on monkeys are just as poor as those using any other species in predicting the effects on humans.
• A recent study found that out of 93 dangerous drug side effects, only 19% could have been predicted by animal tests.
• Another study showed that over 1,000 potential stroke treatments have been “successful” in animal tests, but of the approximately 10% that progressed to human trials, none worked sufficiently well in humans.
• One review of 101 high impact discoveries based on basic animal experiments found that only 5% resulted in approved treatments within 20 years. More recently, we conducted an analysis of 27 key animal-based ‘breakthroughs ’ that had been reported by the UK press 25 years earlier. Mirroring the earlier study, we found only one of the 27 “breakthroughs” had been realised in humans, and that was subject to several caveats.

Dangerous animal testing

• Vioxx, a drug used to treat arthritis, was found to be safe when tested in monkeys (and five other animal species) but has been estimated to have caused around 140,000 heart attacks and strokes and 60,000 deaths worldwide.
• Human volunteers testing a new monoclonal antibody treatment (TGN1412) at Northwick Park Hospital, UK, in 2006 suffered a severe immune reaction and nearly died. Testing on monkeys at 500 times the dose given to the volunteers totally failed to predict the dangerous side effects.
• A drug trial in France resulted in the death of one volunteer and left four others severely brain damaged in 2016. The drug, which was intended to treat a wide range of conditions including anxiety and Parkinson’s disease, was tested in four different species of animals (mice, rats, dogs and monkeys) before being given to humans.
• A clinical trial of Hepatitis B drug fialuridine had to be stopped because it caused severe liver damage in seven patients, five of whom died. It had been tested on animals first.

Animals are different

• Animals do not get many of the diseases we do, such as Parkinson’s disease, major types of heart disease, many types of cancer, Alzheimer’s disease, HIV or schizophrenia.
• An analysis of over 100 mouse cell types found that only 50% of the DNA responsible for regulating genes in mice could be matched with human DNA.
• The most commonly used species of monkey to test drug safety (Cynomolgous macaque monkeys) is resistant to doses of paracetamol (acetaminophen) that would be deadly in humans.
• Chocolate, grapes, raisins, avocados and macadamia nuts are harmless in humans but toxic to dogs.
• Aspirin is toxic to many animals and would not be on our pharmacy shelves if it had been tested according to current animal testing standards.

The science relating to animal experiments can be extremely complicated and views often differ. What appears on this website represents Cruelty Free International expert opinion, based on a thorough assessment of the evidence.

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subtitle: Alternatives to animal tests are often cheaper, quicker and more effective.

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Animal testing is carried out in a wide range of areas, including biological research, and testing medicines and chemicals.

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Millions of animals are used and killed in the name of progress every year.

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Animals used in laboratories are deliberately harmed, not for their own good, and are usually killed at the end of the experiment.

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Most animals in laboratories are not legally protected.

Animal testing is a cruel and gruesome industry.

Animals are subjected to horrifically painful experiments, oftentimes without pain killers. There is little regulation or meaningful oversight of the labs in which animals are experimented on. And for all that pain, experts say that the testing isn’t even effective.

This page will walk you through the federal laws and agencies involved with animal testing, the major efforts on behalf of laboratory animals, and how you can help.

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Overview: The Horrors Of Animal Testing

Tens of millions of animals are used in laboratory experiments every year in the United States — and by most estimates, between 85 and 95% of these animals are not protected by the law. Those without protection are complex beings who think and feel pain, just the same as those who have legal protections.

This figure is only an approximation because under current law, labs are not required to disclose data about the animals most often used in experimentation — rats, mice, birds, and fish.

Animals are used across fields, in many types of research: biomedical, aeronautic, automotive, military, agricultural, behavioral, and cognitive research, and in consumer product testing. It’s estimated that the National Institutes of Health spends some $14.5 billion per year of taxpayer dollars on animal experimentation. The overall amount spent on animal research is likely far higher, given that the $14.5 billion figure doesn’t include spending by other federal agencies like the U.S. Department of Agriculture or animal research funded by private companies.

Thanks to better technology and increasing public demand, we have seen some progress.

For example, after decades of scrutiny and pressure from animal protection groups, the general public and the international community, in 2015 the National Institutes of Health announced the agency would no longer support the use of chimpanzees in biomedical research. Since that time, NIH has retired some chimpanzees to sanctuaries as space is available, and has reportedly convened a working group to develop plans for chimpanzees deemed too old or sick to be safely relocated.

But our work here is far from done. Despite legal requirements to do so under principles known as the “3 Rs” — reduction, refinement, and replacement — many facilities don’t adequately look for alternatives to animal-based tests.

Experts also recognize the need for more change. In 2007, the National Research Council — an organization that puts out reports and policy recommendations for The National Academies of Sciences, Engineering, and Medicine — issued a report on toxicity testing that recommended a move away from the use of animals in laboratory experiments.

Many scientists believe that in vitro testing is scientifically superior to inhumane testing on animals. The same is true for radiation exposure tests and cosmetic testing. Technology, such as non-invasive imaging, provide alternatives to cutting into animals’ brains. Cancer antibody testing is better conducted with human cells than by injecting mice with cancer.

On top of that, animal testing does not achieve its intended results. According to the U.S. Food and Drug Administration (FDA), just 8% of drugs tested on animals are deemed safe and effective for human use — 92% are not. This helps bolster the argument that animal testing does not provide enough worthwhile information to justify its wide scale cruelty, and calls into question the ethics of animal testing.

We’ve seen important promising developments, but the millions of animals experimented on in United States labs every year show how much more is still needed.

The Animal Legal Defense Fund calls on government agencies to be more transparent in their treatment of animals used in research. We file lawsuits to compel taxpayer-funded research facilities to follow records laws, so that public funds are used with public awareness.

We work throughout the legal system to secure better protections for animals used in research, and better enforcement of those protections.

92% of drugs tested on animals fail to meet the standards for human use, and this rate is growing, not improving.

Food and Drug Administration

Take a Stand Against Animal Testing

Did you know an estimated 100 million animals are used in testing and research in the United States every year? Take a stand against animal testing by signing our cruelty-free pledge today.

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Pro and Con: Animal Testing

To access extended pro and con arguments, sources, and discussion questions about whether animals should be used for scientific or commercial testing, go to ProCon.org .

An estimated 26 million animals are used every year in the United States for scientific and commercial testing. Animals are used to develop medical treatments, determine the toxicity of medications, check the safety of products destined for human use, and other biomedical, commercial, and health care uses. Research on living animals has been practiced since at least 500 BC.

Animal testing in the United States is regulated by the federal Animal Welfare Act (AWA), passed in 1966 and amended in 1970, 1976, and 1985.The AWA defines “animal” as “any live or dead dog, cat, monkey (nonhuman primate mammal), guinea pig, hamster, rabbit, or such other warm blooded animal.” The AWA excludes birds, rats and mice bred for research, cold-blooded animals, and farm animals used for food and other purposes.

A public outcry over animal testing and the treatment of animals in general broke out in the United States in the mid-1960s, leading to the passage of the AWA. An article in the November 29, 1965 issue of Sports Illustrated about Pepper , a farmer’s pet Dalmation that was kidnapped and sold into experimentation, is believed to have been the initial catalyst for the rise in anti-testing sentiment. Pepper died after researchers attempted to implant an experimental cardiac pacemaker in her body.

The COVID-19 (coronavirus) global pandemic brought attention to the debate about animal testing as researchers sought to develop a vaccine for the virus as quickly as possible. Vaccines are traditionally tested on animals to ensure their safety and effectiveness. News broke in Mar. 2020 that there was a shortage of the genetically modified mice that were needed to test coronavirus vaccines.

Meanwhile, other companies tried new development techniques that allowed them to skip animal testing and start with human trials. Moderna Therapeutics used a synthetic copy of the virus genetic code instead of a weakened form of the virus. The FDA approved an application for Moderna to begin clinical trials on a coronavirus vaccine on Mar. 4, 2020, and the first participant was dosed on Mar. 16, 2020.

Pro Arguments

Animal testing contributes to life-saving cures and treatments..

The California Biomedical Research Association states that nearly every medical breakthrough in the last 100 years has resulted directly from research using animals. [9] Animal research has contributed to major advances in treating conditions such as breast cancer, brain injury, childhood leukemia, cystic fibrosis, multiple sclerosis, tuberculosis, and more, and was instrumental in the development of pacemakers, cardiac valve substitutes, and anesthetics. [10][11][12][13]

Animal testing is crucial to ensure that vaccines are safe.

Scientists racing to develop a vaccine for coronavirus during the 2020 global pandemic need to test on genetically modified mice to ensure that the vaccine doesn’t make the virus worse. [133] [119] Nikolai Petrovsky, professor in the College of Medicine and Public Health at Flinders University in Australia, said testing a coronavirus vaccine on animals is “absolutely essential” and skipping that step would be “fraught with difficulty and danger.” [133]

Researchers have to test extensively to prevent “vaccine enhancement,” a situation in which a vaccine actually makes the disease worse in some people. [141] Peter Hotez, Dean for the National School of Tropical Medicine at Baylor College, said, “The way you reduce that risk is first you show it does not occur in laboratory animals.” [119]

There is no adequate alternative to testing on a living, whole-body system.

A living systems, human beings and animals are extremely complex. Studying cell cultures in a petri dish, while sometimes useful, does not provide the opportunity to study interrelated processes occurring in the central nervous system, endocrine system, and immune system. [9] Evaluating a drug for side effects requires a circulatory system to carry the medicine to different organs. [15]

Conditions such as blindness and high blood pressure cannot be studied in tissue cultures. [9] Even the most powerful supercomputers are unable to accurately simulate the workings of the human brain’s 100 billion interconnected nerve cells. [132]

Animals are appropriate research subjects because they are similar to human beings in many ways.

Chimpanzees share 99% of their DNA with humans, and mice are 98% genetically similar to humans. [9] All mammals, including humans, are descended from common ancestors, and all have the same set of organs (heart, kidneys, lungs, etc.) that function in essentially the same way with the help of a bloodstream and central nervous system. [17] Because animals and humans are so biologically similar, they are susceptible to many of the same conditions and illnesses, including heart disease, cancer, and diabetes. [18]

Animals must be used in cases when ethical considerations prevent the use of human subjects.

When testing medicines for potential toxicity, the lives of human volunteers should not be put in danger unnecessarily. It would be unethical to perform invasive experimental procedures on human beings before the methods have been tested on animals, and some experiments involve genetic manipulation that would be unacceptable to impose on human subjects before animal testing. [19] The World Medical Association Declaration of Helsinki states that human trials should be preceded by tests on animals. [20]

Animals themselves benefit from the results of animal testing.

Vaccines tested on animals have saved millions of animals that would otherwise have died from rabies, distemper, feline leukemia, infectious hepatitis virus, tetanus, anthrax, and canine parvo virus. Treatments for animals developed using animal testing also include pacemakers for heart disease and remedies for glaucoma and hip dysplasia. [9][21]

Animal testing has been instrumental in saving endangered species from extinction, including the black-footed ferret, the California condor and the tamarins of Brazil. [13][9] The American Veterinary Medical Association (AVMA) endorses animal testing to develop safe drugs, vaccines, and medical devices. [23]

Animal research is highly regulated, with laws in place to protect animals from mistreatment.

In addition to local and state laws and guidelines, animal research has been regulated by the federal Animal Welfare Act (AWA) since 1966. As well as stipulating minimum housing standards for research animals (enclosure size, temperature, access to clean food and water, and others), the AWA also requires regular inspections by veterinarians. [3]

All proposals to use animals for research must be approved by an Institutional Animal Care and Use Committee (IACUC) set up by each research facility. Most major research institutions’ programs are voluntarily reviewed for humane practices by the Association for Assessment and Accreditation of Laboratory Animal Care International (AAALAC). [24][25]

Animals often make better research subjects than human beings because of their shorter life cycles.

Laboratory mice, for example, live for only two to three years, so researchers can study the effects of treatments or genetic manipulation over a whole lifespan, or across several generations, which would be infeasible using human subjects. [29][9] Mice and rats are particularly well-suited to long-term cancer research, partly because of their short lifespans. [30]

Animal researchers treat animals humanely, both for the animals’ sake and to ensure reliable test results.

Research animals are cared for by veterinarians, husbandry specialists, and animal health technicians to ensure their well-being and more accurate findings. Rachel Rubino, attending veterinarian and director of the animal facility at Cold Springs Harbor Laboratory, said, “Most people who work with research animals love those animals… We want to give them the best lives possible, treat them humanely.” [28] At Cedars-Sinai Medical Center’s animal research facility, dogs are given exercise breaks twice daily to socialize with their caretakers and other dogs, and a “toy rotation program” provides opportunities for play. [32]

Animals do not have rights, therefore it is acceptable to experiment on them.

Animals do not have the cognitive ability or moral judgment that humans do and because of this they have been treated differently than humans by nearly every culture throughout recorded history. If we granted animals rights, all humans would have to become vegetarians, and hunting would need to be outlawed. [33][34]

The vast majority of biologists and several of the largest biomedical and health organizations in the United States endorse animal testing.

A poll of 3,748 scientists by the Pew Research Center found that 89% favored the use of animals in scientific research. [120] The American Cancer Society, American Physiological Society, National Association for Biomedical Research, American Heart Association, and the Society of Toxicology all advocate the use of animals in scientific research. [36][37][38][39][40]

Some cosmetics and health care products must be tested on animals to ensure their safety.

American women use an average of 12 personal care products per day, so product safety is of great importance. [41] The US Food and Drug Administration endorses the use of animal tests on cosmetics to “assure the safety of a product or ingredient.” [42] China requires that most cosmetics be tested on animals before they go on sale, so cosmetics companies must have their products tested on animals if they want distribution in one of the largest markets in the world. [43] Manufacturers of products such as hand sanitizer and insect repellent, which can protect people from Zika, malaria, and West Nile Virus, test on animals to meet legal requirements for putting these products on the market. [44]

Supporting Quotes 

Tara Rabin, Public Affairs Specialist at the Food and Drug Administration, as quoted in a Sep. 10, 2019 article, “E.P.A. Says It Will Drastically Reduce Animal Testing,” by Mihir Zaveri, Mariel Padilla and Jaclyn Peiser, available at nytimes.com, stated,

While the F.D.A. is committed to doing all that it can to reduce the reliance on animal-based studies, there are still many areas where animal research is necessary. Without the use of animals, it would be impossible to gain some of the important knowledge needed to prevent human and animal suffering for many life-threatening diseases.

Mieke Louwe, PhD, Postdoctoral Researcher at the Research Institute of Internal Medicine an the K.G. Jebsen Inflammation Research Centre at the Oslo University Hospital at Oslo University, stated the following in an Apr. 16, 2016 article “What You Should Know about Animal Research,” available at the Science Nordic website:

Unfortunately, however, not all animal research can be replaced by animal free experiments. One reason is that there are no alternative methods that can mimic the whole human body. For instance, studying how cancer spreads from one part of the body to another is impossible with current alternatives. Actually, to study any process that involves more than one organ requires the use of an animal, as the interaction that takes place between different organs is very complex. Up till now it is impossible to replicate this in a cell culture dish… [T]here’s no doubt that the work to reduce the use of animals in research is something that needs to be further addressed, and hopefully we will be able to find adequate alternatives for all kinds of research. But until we reach that stage, medical progress is not possible without exploiting animals.

Juan Carlos Marvizón, PhD, Adjunct Associate Professor for CURE: Digestive Diseases Research Center at the University of California at Los Angeles (UCLA), stated the following in a Jan. 5, 2016 article “Can Animal Research Be Applied to Humans,” available at the Speaking of Research website:

Physiology is similar enough between humans and the rest of mammals to make it possible to translate discoveries from animals to humans. Furthermore, science has developed the right strategies to investigate human diseases in animals and use the findings to develop medications that work in humans (and in animals as well, in the case of veterinary medicine)…Not everything is smooth sailing, there are some big obstacles in translating discoveries made in animals to humans. Nobody said that science was easy. However, giving up animal research following the advice of animal rights ideologues would the most foolhardy thing to do. The ultimate proof that animal research is able to produce cures for human diseases.

The Royal Society of Biology stated the following in their publication “Animal Research: The Use of Animals in Research,” available at rsb.org.uk (accessed Mar. 7, 2017):

The Royal Society of Biology supports the use of animals in research when properly regulated and when no alternatives are available. We actively support progress towards a reduction in the use of animals by refining experiments and developing new ways to minimise the use of and replace animals wherever possible – often referred to as the 3Rs. Research using animals has directly contributed to medical and veterinary benefits including development of vaccines, antibiotics, and pioneering medical procedures that save and improve the quality of many human and animal lives. It has played a vital role in the major medical advances of the past century. It will continue to be necessary for some time as we search for treatments for life-threatening conditions such as cancer, Alzheimer’s and Parkinson’s diseases, AIDS, trauma and many severe infectious and inherited diseases… [T]here are groups and individuals that wish to stop animal research completely, claiming that it is unnecessary and brings no benefit. However, as set out above, this is not the case.

Dario L. Ringach, PhD, MSc, Professor of Neurobiology and Psychology at the University of California at Los Angeles, stated in his article titled “The Use of Nonhuman Animals in Biomedical Research,” published in the Oct. 2011 issue of the American Journal of the Medical Sciences:

The contributions of animal research to medical science and human health are undeniable… When the majority of scientists see the work as scientifically justified, and so do the many professional medical and scientific organizations, the expert views cannot be simply dismissed based on wild claims of ulterior motives, self-interest and conspiracy theories. Why is the use of animals in scientific experimentation morally permissible? In my view, it is because the moral status of animals is not equal to that of humans and because opting out of the research condemns our patients (both animal and human) to suffer and die of disease. Stopping the research would be, as Darwin correctly judged, a crime against humanity. I have come to appreciate the compassion animal activists have toward animals. Paradoxically, this compassion does not seem to extent to human patients. Hopefully, animal activists will come to accept that our work is driven similarly by an honest attempt at advancing knowledge and alleviating suffering and disease in the world.

William T. Talman, MD, Professor of Neurology and Neuroscience at the University of Iowa, stated in his Dec. 7, 2012 Huffington Post article titled “Don’t Have the Wool Pulled over Your Eyes”:

[C]onsider that over the past 40 years only one Nobel Prize in Physiology or Medicine did not depend on animal research for the fundamental discoveries that led to the prize… A quick look at the list of Nobel Prizes in Physiology or Medicine will give you an idea not only of the vital role played by animals in biomedical research, but also the impact that research has had on humankind… Sometimes those who seek to outlaw use of animals in research argue that testing new treatments should be done on humans, not animals. Really! Are they ready to volunteer? Even if they were, or even if some were coerced to do so (say prisoners or terminally ill patients), would we really want to move our society in that direction?… Do not think that the only value coming from studies utilizing animals is development of cures or testing of potential cures. In fact, studying living creatures gives the scientist an opportunity to learn how living systems work. The new knowledge often expands our understanding of human physiology…It is important to realize that studies in animals are not just done for, and do not just lead to, treatments in humans. Indeed, treatments for other animals also arise from such studies. Consider, for example, that paralyzed dogs have regained their ability to walk as a result of research conducted in rodents and dogs.

The Foundation for Biomedical Research (FBR) stated in its article titled “Benefits of Biomedical Research,” available on the FBR website (accessed Oct. 24, 2013):

From the discovery of antibiotics, analgesics, anti-depressants, and anesthetics, to the successful development of organ transplants, bypass surgery, heart catheterization, and joint replacement, practically every present-day protocol for the prevention, control, and cure of disease is based on knowledge attained through research with laboratory animals… Animal research has also paid incalculable benefits to animals. It has resulted in many remarkable lifesaving and life-extending treatments for cats, dogs, farm animals, wildlife, and endangered species. Pacemakers, artificial joints, organ transplants, and freedom from arthritic pain are just a few of the breakthroughs made in veterinary medicine thanks to animal research. Dogs, cats, sheep, and cattle are also living longer and healthier lives thanks to vaccines for rabies, distemper, parvo virus, hepatitis, anthrax, tetanus, and feline leukemia. New treatments for glaucoma, heart disease, cancer, hip dysplasia, and traumatic injuries are saving, extending, and enhancing the lives of beloved pets while advanced reproductive techniques are helping to preserve and protect threatened and endangered species.

Laurie Pycroft, founder of Pro-Test (UK), stated in a June 2011 debate titled “Is Animal Testing Necessary to Advance Medical Research?,” posted on the New Internationalist website:

Without the ability to use animals in their research, scientists’ efforts would be massively hampered, not only in the direct development of new treatments, but also in the fundamental research which underpins all biomedical knowledge. For example, it was Alan Lloyd Hodgkin and Andrew Huxley’s work on the nerves of squid that elucidated the basis of nervous transmission; and it was John C Eccles’ work on cats’ spinal cords that first incontrovertibly demonstrated the nature of the synapse, earning him a share of the 1963 Nobel in Physiology, along with Hodgkin and Huxley. Without their work on animals, we would know far less about the workings of our own nervous systems and how to treat them… [R]esearchers have devised many routes of minimizing inter-species variation, such as the use of transgenic animals – genetically altered to replicate human physiology more closely. This has additional benefits, including shorter generation-span, allowing scientists to perform experiments which simply would not be possible using humans (even ignoring ethical concerns)… Claiming that microfluidics and microdosing can analyze drug effects on a full living system is absurd. How can a fluid-based chip replicate the most basic heart, let alone a human one? Microdosing can be useful for studying uptake mechanisms of a drug, but gives extremely limited information on its efficacy at treating a condition. ‘Alternatives’ are already widely used in research, but expecting them to replace animal tests in the near future is hugely naïve.

The American Heart Association stated in its “Public Policy Agenda 2010-14,” available at heart.org (accessed Oct. 29, 2013):

Animal research has improved the health and welfare of animals and humans. The decline in death rates in the United States from heart disease and stroke since the 1960s is due to lifestyle changes and new methods of treatment and prevention, many of which are based on animal research.

Americans for Medical Progress (AMP) stated in its article titled “Animal Research,” posted on the AMP website (accessed Oct. 24, 2013):

Animal research plays a crucial role in scientists’ understanding of diseases and in the development of effective medical treatments. Research animals provide scientists with complex living systems consisting of cells, tissues and organs.  Animal models can interact and react to stimuli, giving researchers a picture of a compound moving through a living system and an idea of how that stimuli might react in a human being.  Animals are biologically similar to humans in many ways and they are vulnerable to over 200 of the same health problems.  This makes them an effective model for researchers to study.

The American Association for Laboratory Animal Science (AALAS) stated in its “Animal Research FAQ,” posted on the AALAS website (accessed Apr. 7, 2017):

The use of animals in research is a privilege that must be carefully guarded to assure human and animal relief from the specter of disease and suffering. To ignore human and animal suffering is irresponsible and unethical. Nearly every major medical advance of the 20th century has depended largely on research with animals. Our best hope for developing preventions, treatments and cures for diseases such as Alzheimer’s, AIDS and cancer will also involve biomedical research using animals. In fact, research on animals is in many cases an obligation. According to the Nuremburg Code, drawn up after World War II as a result of Nazi atrocities, any experiments on humans ‘should be designed and based on the results of animal experimentation.’… The Declaration of Helsinki, adopted in 1964 by the 18th World Medical Assembly and revised in 1975, also states that medical research on human subjects ‘should be based on adequately performed laboratory and animal experimentation.

Tom Holder, founder of Speaking of Research, stated in his Jan. 14, 2013 article titled “Animal Research Is an Ethical and Vital Tool to Fight Disease,” posted on the Harvard Law Petrie-Flom Center blog “Bill of Health”:

In the US alone there are over 95 million prescriptions every year for asthma medications, primarily inhalers. So what can over 25 million American asthma sufferers thank for making their lives manageable? The guinea pigs and frogs which allowed scientists to gain the underlying understanding about how chemical nerve transmitters helped to control the muscles in the airways, as well as create reliever inhalers with a long duration of action. This is just one example of a long list of medical achievements made possible by animal research which include insulin (dogs and rabbits), polio vaccine (monkeys), anaesthetics (rabbits), blood transfusion (monkeys, dogs), antibiotics to cure tuberculosis (guinea pigs), asthma treatment (frogs and guinea pigs), meningitis vaccine (mice), deep brain stimulation (monkeys), penicillin (mice)… In a country where we eat 9 billion chickens and 150 million cattle, pigs and sheep every year, 25 million (approx.) animals (96% is estimated to be mice, rats, birds and fish) seems a small price to pay for medical progress.

AnimalResearch.info stated in its article titled “Why Animals Are Used,” posted on its website (accessed Apr. 7, 2017):

Animals are used in research when there is a need to find out what happens in the whole, living body, which is far more complex than the sum of its parts. It is difficult, and in most cases simply not yet possible, to replace the use of living animals in research with alternative methods… Humans and animals share hundreds of illnesses, and consequently animals can act as models for the study of human illness. For example, rabbits suffer from atherosclerosis (hardening of the arteries), as well as diseases such as emphysema, and birth defects such as spina bifida. Dogs suffer from cancer, diabetes, cataracts, ulcers and bleeding disorders such as haemophilia, which make them natural candidates for research into these disorders. Cats suffer from some of the same visual impairments as humans… New medicines require testing because researchers must measure both the beneficial and the harmful effects of a compound on a whole organism. A medicine is initially tested in vitro using tissues and isolated organs, but legally and ethically it must also be tested in a suitable animal model before clinical trials in humans can take place.

The American Physiological Society (APS) said in its July 16, 2010 position statement titled “Animal Research Is Essential to the Search for Cures,” posted on the APS website:

Humane research involving animals provides unique insights into biological structure and function. These insights offer major benefits to both human and animal health. The American Physiological Society is strongly committed to ensuring that research animals are treated humanely and that their use is regulated appropriately. Biomedical research today involves a wide array of approaches that make use of computers, molecules, cells, tissues, organs, and whole animals. Each approach addresses different elements of a research question. Together, they offer a full complement of ways to learn about living systems. Animal studies are particularly crucial for understanding how the body functions in health and disease. Basic and translational research involving animals is a necessary component in the search for causes, preventions, treatments, and cures for disease.

The American College of Laboratory Animal Medicine (ACLAM) said in its “Position Statement on Animal Experimentation,” posted at aclam.org (accessed Oct. 29, 2013):

Scientific research requiring laboratory animals continues to result in spectacular achievements that have advanced our understanding of life and treatment of disease. Continued progress – to benefit human and animal health – requires further animal experimentation because there is, as yet, no single or array of alternative systems that permit the complete replacement for animals. Basic and applied research with animals provides invaluable and currently irreplaceable means to study human conditions because there are so many similarities between the physiology and genetics of animals and humans. While not all systems in animals and man are exactly the same, the differences in many cases are sufficiently small that animals can serve as relevant models for man or other species. Humane and responsible animal research offers the best hope for the development of new methods of prevention, treatment, cure and control of disease, pain and suffering. Animal based research is and will be, for the foreseeable future, indispensable to biomedical progress – for humans and animals.

Charles Darwin, MA, British naturalist and originator of the theory of evolution, stated in a letter printed in the Times (UK), dated Apr. 14, 1881 and available at darwin-online.org.uk:

I have all my life been a strong advocate for humanity to animals, and have done what I could in my writings to enforce this duty… On the other hand, I know that physiology cannot possibly progress except by means of experiments on living animals, and I feel the deepest conviction that he who retards the progress of physiology commits a crime against mankind.

Con Arguments

Animal testing is cruel and inhumane..

According to Humane Society International, animals used in experiments are commonly subjected to force feeding, food and water deprivation, the infliction of burns and other wounds to study the healing process, the infliction of pain to study its effects and remedies, and “killing by carbon dioxide asphyxiation, neck-breaking, decapitation, or other means.” [47] The US Department of Agriculture reported in Jan. 2020 that research facilities used over 300,000 animals in activities involving pain in just one year. [102]

Scientists are able to test vaccines on humans volunteers.

Unlike animals used for research, humans are able to give consent to be used in testing and are a viable option when the need arises. [142] The COVID-19 (coronavirus) global pandemic demonstrated that researchers can skip animal testing and go straight to observing how vaccines work in humans. One company working on a COVID-19 vaccine, Moderna Therapeutics, worked on developing a vaccine using new technology: instead of being based on a weakened form of the virus, it was developed using a synthetic copy of the COVID-19 genetic code. [143]

Because the company didn’t take the traditional path of isolating live samples of a virus, it was able to fast-track the development process. [144] Tal Zaks, chief medical officer at Moderna, said, “I don’t think proving this in an animal model is on the critical path to getting this to a clinical trial.” [145]

Alternative testing methods now exist that can replace the need for animals.

Other research methods such as in vitro testing (tests done on human cells or tissue in a petri dish) offer opportunities to reduce or replace animal testing. [15] Technological advancements in 3D printing allow the possibility for tissue bioprinting: a French company is working to bioprint a liver that can test the toxicity of a drug. [16] Artificial human skin, such as the commercially available products EpiDerm and ThinCert, can be made from sheets of human skin cells grown in test tubes or plastic wells and may produce more useful results than testing chemicals on animal skin. [15][50][51]

The Environmental Protection Agency is so confident in alternatives that the agency intends to reduce chemical testing on mammals 30% by 2025 and end it altogether by 2035. [134] Humane Society International found that animal tests were more expensive than in vitro (testing performed outside of living organisms) in every scenario studied. [61]

Animals are very different from human beings and therefore make poor test subjects.

The anatomic, metabolic, and cellular differences between animals and people make animals poor models for human beings. [52] Paul Furlong, Professor of Clinical Neuroimaging at Aston University (UK), states that “it’s very hard to create an animal model that even equates closely to what we’re trying to achieve in the human.” [53] Thomas Hartung, Professor of evidence-based toxicology at Johns Hopkins University, argues for alternatives to animal testing because “we are not 70 kg rats.” [54]

Drugs that pass animal tests are not necessarily safe.

The 1950s sleeping pill thalidomide, which caused 10,000 babies to be born with severe deformities, was tested on animals prior to its commercial release. [5] Later tests on pregnant mice, rats, guinea pigs, cats, and hamsters did not result in birth defects unless the drug was administered at extremely high doses. [109][110] Animal tests on the arthritis drug Vioxx showed that it had a protective effect on the hearts of mice, yet the drug went on to cause more than 27,000 heart attacks and sudden cardiac deaths before being pulled from the market. [55][56]

Animal tests may mislead researchers into ignoring potential cures and treatments.

Some chemicals that are ineffective on (or harmful to) animals prove valuable when used by humans. Aspirin, for example, is dangerous for some animal species. [105] Intravenous vitamin C has shown to be effective in treating sepsis in humans, but makes no difference to mice. [127] Fk-506 (tacrolimus), used to lower the risk of organ transplant rejection, was “almost shelved” because of animal test results, according to neurologist Aysha Akhtar. [105] A report on Slate.com stated that a “source of human suffering may be the dozens of promising drugs that get shelved when they cause problems in animals that may not be relevant for humans.” [106]

Only 5% of animals used in experiments are protected by US law.

The Animal Welfare Act (AWA) does not apply to rats, mice, fish, and birds, which account for 95% of the animals used in research. [28] The types of animals covered by the AWA account for fewer than one million animals used in research facilities each year, which leaves around 25 million other animals without protection from mistreatment. [1][2][26][102] [135] The US Department of Agriculture, which inspects facilities for AWA compliance, compiles annual statistics on animal testing but they only include data on the small percentage of animals subject to the Act. [135]

Animal tests do not reliably predict results in human beings.

94% of drugs that pass animal tests fail in human clinical trials. [57] According to neurologist Aysha Akhtar, MD, MPH, over 100 stroke drugs that were effective when tested on animals have failed in humans, and over 85 HIV vaccines failed in humans after working well in non-human primates. [58] A study published in Proceedings of the National Academy of Sciences of the United States of America (PNAS) found that nearly 150 clinical trials (human tests) of treatments to reduce inflammation in critically ill patients have been undertaken, and all of them failed, despite being successful in animal tests. [59][58]

There is increasing demand for cruelty-free products.

More than one-third of women only buy cosmetics from brands that do not use animal testing. [136] The market for cruelty-free cosmetics (products not tested on animals) is estimated to reach $10 billion by 2024. [137] At least 37 countries have banned or restricted the sale of cosmetics with ingredients tested on animals, including nations in the European Union. [138] In the US, California became the first state to make it illegal to sell most cosmetics that underwent animal testing. [139]

Michael Bachelor, Senior Scientist and Product Manager at biotech company MatTek, stated, “We can now create a model from human skin cells — keratinocytes — and produce normal skin or even a model that mimics a skin disease like psoriasis. Or we can use human pigment-producing cells — melanocytes — to create a pigmented skin model that is similar to human skin from different ethnicities. You can’t do that on a mouse or a rabbit.” [140]

Most experiments involving animals are flawed, wasting the lives of the animal subjects.

A peer-reviewed study found serious flaws in the majority of publicly funded US and UK animal studies using rodents and primates: “only 59% of the studies stated the hypothesis or objective of the study and the number and characteristics of the animals used.” [64] A 2017 study found further flaws in animal studies, including “incorrect data interpretation, unforeseen technical issues, incorrectly constituted (or absent) control groups, selective data reporting, inadequate or varying software systems, and blatant fraud.” [128]

The Animal Welfare Act has not succeeded in preventing horrific cases of animal abuse in research laboratories.

Violations of the Animal Welfare Act at the federally funded New Iberia Research Center (NIRC) in Louisiana included maltreatment of primates who were suffering such severe psychological stress that they engaged in self-mutilation, infant primates awake and alert during painful experiments, and chimpanzees being intimidated and shot with a dart gun. [68]

Medical breakthroughs involving animal research may still have been made without the use of animals.

Devoting enough money and resources to animal-free alternatives could result in the same medical advances achieved through animal testing. [107] [129] [130] Humane Research Australia (HRA) reports that many discoveries made by non-animal methods were later verified by animal experiments, “giving false credit” to animal use. [130]

Supporting Quotes

Andrew Wheeler, JD, MBA, Administrator of the Environmental Protection Agency, in a Sep. 10, 2019 memo available at fda.gov with the subject line, “Directive to Prioritize Efforts to Reduce Animal Testing,” stated,

We can protect human health and the environment by using cutting-edge, ethically sound science in our decision-making that efficiently and cost-effectively evaluates potential effects without animal testing.

Lindsay Marshall, PhD, Science Communications Officer at the Humane Society of the United States and Humane Society International (HSUS/HSI), stated the following in a Dec. 16, 2016 article “Science in Transit; The Move Away from Animals in Research,” available at the Huffington Post website:

Animal research certainly fails animals, in terms of the distress and suffering caused, and just as importantly, animal research often fails people, too, in terms of the slow, unproductive route to useful treatments. More than 90 percent of drugs that have passed animal trials for safety and efficacy are not successful in treating the human disease for which they are intended… [S]urely we can all agree that replacement of animals in testing and research is morally, ethically and scientifically the only way forward.

John Pippin, MD, FACC, Cardiologist and Director of Academic Affairs for Physicians Committee for Responsible Medicine, stated the following in a May 18, 2016 article “Statement from the Physicians Committee on Johns Hopkins University Eliminating the Use of Animals in Medical Training,” available at pcrm.org:

It is a tremendous relief to hear that Johns Hopkins University will finally begin using up-to-date, human-relevant methods to teach human medicine. This change will align Johns Hopkins’ medical education program with 99 percent of the country’s programs… [T]he use of animal labs is unmistakably contrary to the intention to provide an excellent medical education. Modern medical simulators provide a superior way to learn surgical skills that are specific to human anatomy and physiology. To prepare future physicians for the work they will perform throughout their careers, medical training must be human-focused, not animal-focused, because there are many substantial differences across species.

Kathy Archibald, Founder and Director of the Safer Medicines Trust, stated in her chapter “Of Mice but Not Men,” in the 2016 book What Doctors Don’t Tell You:

Not only are animals poor models of safety for humans, but they are also unreliable for demonstrating the effectiveness of treatments too. Just as many drugs fail in clinical trials because they turn out to cause side-effects in humans, many others turn out to be ineffective in humans, despite performing well in animals. This makes drug development extraordinarily expensive because companies need to recoup the costs of clinical trials not only for successful drugs, but also for the nine others that fail for each one that succeeds… [F]ar from jeopardizing progress, a shift to advanced techniques based on human biology would accelerate biomedical research, and deliver safer and better medicines at lower costs: a win–win situation that should be supported by everyone.

Aysha Akhtar, MD, MPH, neurologist and author of Animals and Public Health: Why Treating Animals Better Is Critical to Human Welfare, stated in her Oct. 21, 2013 email to ProCon.org:

Regardless of any role animal experiments may have played in the past, the mounting evidence shows that using animals today is largely ineffective in helping us understand human physiology, predict human toxins and find useful drugs. Despite some similarities between humans and non-human animals, medicine now deals with the subtle nuances of physiological mechanisms and genetics that are unique to humans. While animals may be ‘whole models,’ they are the wrong whole models because of inter-species differences. Failures of animal experiments have led to human harm. Moreover, misleading animal experiments may have caused the abandonment of effective drugs and cures. One can’t help wonder: how many people would have been saved if we used more effective human-based testing methods? Animal experimentation is a relic of the past. Instead of wasting time, human and animal lives, and our tax dollars on misleading animal experiments, we must devote our resources into finding and using sophisticated human-based tests that mimic the whole human body. Our lives depend on this.

Jane Goodall, PhD, ethologist and author, stated in her Mar. 17, 2012 op-ed for the Times (UK) titled “So Much Animal Pain, So Little Human Gain”:

In the name of science or medicine, animals are subjected to countless invasive, frightening and sometimes very painful procedures. We all want to see cures for terrible diseases such as Parkinson’s (which afflicted my mother), cancer (to which I lost my husband), multiple sclerosis and so on, but regardless of how much or how little these experiments benefit human health, should we exploit animals in this way? Animal experimenters often justify such research by claiming the existence in humans of some morally relevant characteristics, such as intelligence, language, or consciousness, that are supposedly absent in other species. But we are fast discovering a great deal about high levels of intelligence in many animal species, and too about animal consciousness, emotions and sensitivity to pain… We need a new mindset for the 21st century. Most experimenters, while acknowledging that animals are sentient and sometimes sapient beings, say that some will always have to be used but they will use as few and treat them as well as possible. Instead, let us admit that the practice is morally and ethically unacceptable. We need to move on. The amazing human brain has already discovered astonishingly innovative ways of improving medical research by replacing animals. Let science direct its collectively awesome intellect toward finding alternatives to the use of live animals in all procedures—as soon as possible. This should be supported by the scientific establishment and vastly increased funding should be found for it. It should be a goal for all civilised societies.

Humane Society International (HSI) stated in its article titled “About Animal Testing,” posted on the HSI website (accessed Apr. 7, 2017):

Aside from the ethical issues they pose—inflicting both physical pain as well as psychological distress and suffering on large numbers of sentient creatures—animal tests are time- and resource-intensive, restrictive in the number of substances that can be tested, provide little understanding of how chemicals behave in the body, and in many cases do not correctly predict real-world human reactions. Similarly, health scientists are increasingly questioning the relevance of research aimed at ‘modeling’ human diseases in the laboratory by artificially creating symptoms in other animal species. Trying to mirror human diseases or toxicity by artificially creating symptoms in mice, dogs or monkeys has major scientific limitations that cannot be overcome. Very often the symptoms and responses to potential treatments seen in other species are dissimilar to those of human patients. As a consequence, nine out of every 10 candidate medicines that appear safe and effective in animal studies fail when given to humans. Drug failures and research that never delivers because of irrelevant animal models not only delay medical progress, but also waste resources and risk the health and safety of volunteers in clinical trials.

Peter Singer, MA, Ira W. DeCamp Professor of Bioethics at Princeton University, stated in the 2009 edition of his book Animal Liberation:

The practice of experimenting on nonhuman animals as it exists today throughout the world reveals the consequences of speciesism. Many experiments inflict severe pain without the remotest prospect of significant benefits for human beings or any other animals. Such experiments are not isolated incidences, but part of a major industry… We tolerate cruelties inflicted on members of other species that would outrage us if performed on members of our own species. Speciesism allows researchers to regard the animals they experiment on as items of equipment, laboratory tools rather than living, suffering creatures. In fact, on grant applications to government funding agencies, animals are listed as ‘supplies’ alongside test tubes and recording instruments… The exploitation of laboratory animals is part of the larger problem of speciesism and it is unlikely to be eliminated altogether until speciesism itself is eliminated. Surely one day, though, our children’s children, reading about what was done in laboratories in the 20th Century, will feel the same sense of horror and incredulity at what otherwise civilized people could do that we now feel when we read about the atrocities of the Roman gladiatorial arenas or the eighteenth-century slave trade.

Marc Bekoff, PhD, former Professor of Ecology and Evolutionary Biology at the University of Colorado and author of The Emotional Lives of Animals, wrote in an Oct. 11, 2013 email to ProCon.org:

There is no reason to continue to use nonhuman animals for scientific or commercial testing. There are ample non-animal alternatives that are readily available that are just as good or better in the Ethical, Economical, and Educational arenas. Many teachers and researchers agree with this point of view.

Andrew Knight, PhD, veterinarian and Fellow of the Oxford Centre for Animal Ethics, stated in his July 12, 2012 article titled “Animal Testing Isn’t Just an Ethical Problem – Let’s Invest in Safer Methods,” posted at theguardian.com:

I analysed in detail 27 systematic reviews examining the contributions of animal experiments to human healthcare. Their outcomes are remarkably consistent. Animal studies rarely contribute to the development of clinical interventions effective in human patients. It’s not hard to fathom why. Animals have a plethora of genetic, biochemical and physiological differences that alter disease progression, drug uptake, distribution and effect. Stressful environments and experiments are common, and distort outcomes. Additionally, numerous studies have revealed scientific flaws in the design of many animal experiments.

People for the Ethical Treatment of Animals (PETA) stated in its article titled “Animal Testing Is Bad Science: Point/Counterpoint,” posted on the PETA website (accessed Oct. 2, 2013):

Most animal experiments are not relevant to human health, they do not contribute meaningfully to medical advances and many are undertaken simply of out [sic] curiosity and do not even pretend to hold promise for curing illnesses. The only reason people are under the misconception that animal experiments help humans is because the media, experimenters, universities and lobbying groups exaggerate the potential of animal experiments to lead to new cures and the role they have played in past medical advances… Because animal tests are so unreliable, they make… human trials all the more risky. The Food and Drug Administration (FDA) has noted that 92 percent of all drugs that are shown to be safe and effective in animal tests fail in human trials because they don’t work or are dangerous.  And of the small percentage that are approved for human use, half are relabeled because of side effects that were not identified in animal tests… Taking a healthy being from a completely different species, artificially inducing a condition that he or she would never normally contract, keeping him or her in an unnatural and distressful environment, and trying to apply the results to naturally occurring diseases in human beings is dubious at best.

The American Anti-Vivisection Society (AAVS) stated in its article titled “Problems with Animal Research,” posted on the AAVS website (accessed Oct. 23, 2013):

Scientists use animals in biological and medical research more as a matter of tradition, not because animal research has proved particularly successful or better than other modes of experimentation. In fact, animal ‘models’ have never been validated, and the claim that animals are necessary for biomedical research is unsupported by the scientific literature. Instead, there is growing awareness of the limitations of animal research and its inability to make reliable predictions about human health. The biomedical research community and its affiliated trade associations routinely attempt to convince the general public, media, and government representatives that the current controversy over the use of animals is a life-and-death contest pitting defenders of human health and scientific advancement against hordes of anti-science, anti-human, emotional, irrational activists. Such a deliberate, simplistic dichotomy is not only false, but ignores the very real and well-documented ethical and scientific problems associated with the use of animal experiments that characterize modern biomedical research, testing, and its associated industries. The biomedical community would instead be better served by promoting increased funding and research efforts for the development of non-animal models that overcome the pressing ethical and scientific limitations of an increasingly archaic system of animal experimentation.

C. Ray Greek, MD, President and Co-Founder of Americans For Medical Advancement (AFMA), stated in his Oct. 29, 2013 email to ProCon.org:

The basis for testing animals prior to human consumption of new medications or releasing new chemicals is that animals offer predictive value for outcomes or conditions in humans. The same is true for using animals in research aimed to find the cause of human disease. In science, predictive value has a very specific meaning and can be calculated. For decades, scientists have known that the positive and negative predictive value for animal models is not useful—the values are so low that scientists know no more about the value or danger of a drug or chemical than they did before testing on animals. Despite this proven lack of value, the process has continued for many reasons. The predictive value of using animals to find causes of, and thereby potential targets for, curing human diseases is even lower. Ethical, human-based research and testing is available and should be more widely implemented.

In Defense of Animals (IDA), an international animal rights and rescue organization, stated in its article titled “Responsible Research,” posted on its website (accessed Oct. 24, 2013):

It is possible, in the twenty-first century, to conduct a vast array of experiments without using animals and to derive better results more quickly and at less cost. Cutting-edge technology has forged new frontiers with the use of lasers, fiber optics, microchips, genomics, computer-based drug design, and digital imaging, to name a few… These methods have contributed to a technological revolution in biomedical research and rendered the reliance on animals outdated. Scientists have only just begun to tap the potential of these new technologies. Their full potential can never be realized while dependence on animal models persists. Reliance on animals continues, not because it is effective, but due to inertia, lack of training, vested financial interests and adherence to outdated traditions… If we took a fraction of the resources currently devoted to animal experiments and put those towards developing and expanding non-animal methods, we could vastly reduce the use of animals immediately and pave way for the day that they are no longer used at all.

Theodora Capaldo, EdD, President and Executive Director of the New England Anti-Vivisection Society (NEAVS), stated in her Jan. 14, 2013 article titled “Inadequate Laws Don’t – but Research Alternatives Will – Protect Animals in Labs,” posted on the Harvard Law Petrie-Flom Center blog “Bill of Health”:

Animals in labs suffer tremendously in the name of science. However, systematic analysis of biomedical literature shows that animals have given us inadequate or erroneous information in human disease and toxicology and that in many cases medical breakthroughs were delayed by dependence on animal models… Even in a species’ whose DNA is nearly identical to humans, the chimpanzee, gene variations and expression result in vast important differences that render even the chimpanzee an ‘unnecessary’ model to study human health and disease. Species differences exist in the process by which a drug is absorbed, distributed, metabolized, and eliminated, and in the causes, progression, and outcome of diseases. As a result, for example, a mouse may develop cancer in the same location as a human, but they are not the same cancers… Non-animal methods are superior on all fronts: they are more efficient, accurate, and cost-effective than animal experiments. Using human cell cultures to test toxicity yields 76-84% accurate prediction, illuminates specific organ damage, and other more meaningful results than animal tests which hover around 46-50% accuracy, literally no better than a coin flip.

Mark Twain, American writer and humorist, stated in his May 26, 1899 letter to the London Anti-Vivisection Society, available in the 2010 book titled Mark Twain’s Book of Animals, edited by Shelley Fisher Fishkin:

I believe I am not interested to know whether Vivisection produces results that are profitable to the human race or doesn’t. To know that the results are profitable to the race would not remove my hostility to it. The pains which it inflicts on unconsenting animals is the basis of my enmity toward it, & is to me sufficient justification of the enmity without looking further.

Did You Know

• 95% of animals used in experiments are not protected by the federal Animal Welfare Act (AWA), which excludes birds, rats and mice bred for research, and cold-blooded animals such as reptiles and most fish. [1] [2] [3]
• 89% of scientists surveyed by the Pew Research Center were in favor of animal testing for scientific research. [120]
• Chimpanzees share 99% of their DNA with humans, and mice are 98% genetically similar to humans. The US National Institutes of Health announced it would retire its remaining 50 research chimpanzees to the Federal Chimpanzee Sanctuary System in 2015, leaving Gabon as the only country to still experiment on chimps. [4] [117]
• A Jan. 2020 report from the USDA showed that in one year of research, California used more cats (1,682) for testing than any other state. Ohio used the most guinea pigs (35,206), and Massachusetts used the most dogs (6,771) and primates (11,795). [102]
• Researchers Joseph and Charles Vacanti grew a human "ear" seeded from implanted cow cartilage cells on the back of a living mouse to explore the possibility of fabricating body parts for plastic and reconstructive surgery. [108]

Take Action

• Consider  Stanford Medicine’s  defense of animal testing.
• Analyze the FDA’s statement on using  animals to test cosmetics .
• Explore  Cruelty Free International , an organization against animal testing.
• Consider how you felt about the issue before reading this article. After reading the pros and cons on this topic, has your thinking changed? If so, how? List two to three ways. If your thoughts have not changed, list two to three ways your better understanding of the “other side of the issue” now helps you better argue your position.
• Push for the position and policies you support by writing US national  senators  and  representatives .

The background and pro and con arguments were written by ProCon.org staff based upon input from the following sources.

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Right now, millions of mice, rats, rabbits, primates, cats, dogs, and other animals are locked inside cages in laboratories across the country. They languish in pain, ache with loneliness, and are deprived of everything that’s natural and important to them. All they can do is sit and wait in fear of the next terrifying and painful procedure that will be performed on them. A lack of environmental enrichment and the stress of their living situations cause some animals to develop neurotic behaviors, such as incessantly spinning in circles, rocking back and forth, pulling out their own fur, and even biting themselves. After enduring lives of pain, loneliness, and terror, almost all of them will be killed.

How PETA Helps Animals in Laboratories

Since PETA’s inception and the landmark  Silver Spring monkeys  case, we’ve been at the forefront of exposing and ending experiments on animals. Our scientists, campaigners, researchers, and other dedicated staff work hard to persuade universities, hospitals,  contract laboratories ,  other companies , and government agencies to abandon animal tests and embrace modern, non-animal methods.

Two teams lead PETA’s efforts to end tests on animals. Our Laboratory Investigations Department focuses on ending the use of animals in experiments not required by law, and our Regulatory Toxicology Department focuses on replacing the use of animals in tests required by law with human-relevant, animal-free toxicity testing approaches. With help from supporters like you, these teams and other hardworking staff at PETA win numerous  victories  for animals imprisoned in laboratories every year. Here’s how they do it:

• Promoting PETA’s Research Modernization Deal , the first comprehensive, science-backed plan to phase out tests on animals
• Conducting groundbreaking  eyewitness investigations and colorful advocacy campaigns to shut down laboratories and areas of animal experimentation
• Filing groundbreaking lawsuits to challenge public funding of wasteful, cruel animal experiments
• Working with members of Congress to enact laws to replace animals in laboratories
• Persuading government agencies to stop conducting and  requiring experiments on animals
• Encouraging  pharmaceutical, chemical , and  consumer product companies to replace tests on animals with more effective, non-animal methods
• Ending the use of animals in experiments at colleges and universities
• Helping  students and  teachers  end animal dissection in the classroom
• Developing and funding humane non-animal research methods
• Publishing scientific papers on reliable non-animal test methods and presenting them at scientific conferences
• Hosting free workshops and online seminars to share information about animal-free toxicity testing methods
• Urging  health charities not to invest in dead-end tests on animals

How Animals Are Exploited in Laboratories

More than 110 million animals suffer and die in the U.S. every year in cruel chemical, drug, food, and cosmetics tests. They also experience this fate in  medical training exercises , curiosity-driven  experiments at universities ,  classroom biology experiments , and  dissection even though modern, non-animal methods have repeatedly been shown to have more educational value, save teachers time, and save schools money. Exact numbers aren’t available, because mice, rats, birds, and cold-blooded animals—who make up more than 99% of animals used in experiments—aren’t covered by even the minimal protections of the federal Animal Welfare Act and therefore go uncounted.

Examples of chemical and toxicity tests on animals include forcing mice and rats to inhale toxic fumes, force-feeding dogs chemicals, and applying corrosive chemicals into rabbits’ sensitive eyes. Even if a product harms animals, it can still be marketed to consumers. Conversely, just because a product was shown to be safe in animals doesn’t guarantee that it will be safe to use in humans.

Much product testing conducted on animals today isn’t required by law. In fact, a number of countries have implemented bans on the testing of certain types of consumer goods on animals, such as the cosmetics testing bans in India, Israel, New Zealand, Norway, and elsewhere.

Meanwhile, at universities and other institutions, experimenters inflict suffering on and kill animals for little more than curiosity’s sake—even though the vast majority of their findings fail to advance human health . They tear baby monkeys away from their mothers , sew kittens’ eyes shut , mutilate owls’ brains , puncture the intestines of mice so that feces leak into their stomachs , and terrorize songbirds with the sounds of predators . At the end of experiments like these—which consume billions in taxpayer funds and charitable donations each year—almost all the animals are killed.

Animal Experiments Throughout History: A Century of Suffering

PETA created an interactive timeline, “ Without Consent ,” featuring almost 200 stories of animal experiments from the past century to open people’s eyes to the long history of suffering inflicted on nonconsenting animals in laboratories and to challenge them to rethink this exploitation. Visit “ Without Consent ” to learn more about harrowing animal experiments throughout history and how you can help create a better future for living, feeling beings.

Advancing Science Without Suffering: Animal-Free Testing

Testing on animals has been a spectacular failure that has resulted in the loss of trillions of dollars and has cost the lives of innumerable humans and other animals. Experiments on one species frequently fail to predict results in another. Even the National Institutes of Health, the world’s largest funder of biomedical research, acknowledges that 95% of all drugs that are shown to be safe and effective in animal tests fail in human trials.

Technologically advanced  non-animal research methods —such as those using human cells, computational models, or clinical studies—can be used in place of animal testing. These methods are more humane, have the potential to be faster, and are more relevant to humans.

Scientists in PETA’s Science Advancement & Outreach division , a part of the Laboratory Investigations Department, have developed a roadmap to phase out failing tests on animals with sophisticated, animal-free methods. Their Research Modernization Deal has gained the support of scientists, medical doctors, members of Congress, and thousands of others who care about ethical and effective science.

How You Can Help Animals Used in Experiments

Each of us can help prevent the suffering and deaths of animals in laboratories. Here are a few easy ways to get started:

• Sign up for PETA’s Action Team to be alerted when protests are taking place in your area.
• Urge your members of Congress to support PETA’s Research Modernization Deal .
• Search PETA’s Beauty Without Bunnies database to ensure that you’re buying only cruelty-free products.
• Donate only to charities that don’t experiment on animals .
• Request alternatives to animal dissection at your school.
• Call on your alma mater to stop experimenting on animals.
• Share information about animal experimentation issues with your friends and family—and invite them to join you in speaking up for animals.

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National Institute of Environmental Health Sciences

Your environment. your health., alternatives to animal testing, what is niehs doing, further reading, introduction.

Advances in science are transforming how scientists study health and disease. Biomedical and behavioral research can involve working with animal models , cells in test tubes, computer modeling, and clinical studies with people. Each research approach is critical to advancing our knowledge of health and disease.

Over the last decade, improved technological capabilities enable scientists to reduce their reliance on animal models for specific types of studies. These advances are important because testing in animals can pose ethical issues, takes significant time and resources, and the relevance to human health is not always certain.

Recent advances in alternative methods, such as computational, biochemical, or cell-based model systems that can replicate human biology, have been shown in some cases to perform the same as or even better than standard animal models. These “New Approach Methodologies” (NAMs, sometimes called Novel Alternative Methods, Non-Animal Methods, or New Alternative Methods) can provide a complementary approach to traditional models. They can offer a way to improve understanding of the human system and its susceptibility to toxic effects, and to discover effective treatments for human conditions.

NIEHS has been a leader in the development of NAMs to reduce the use of animals and increase the human relevance of models in health effects testing. NIEHS is working with the scientific community and other stakeholders to increasingly apply these methods to policy and regulatory decision-making processes or to replace traditional testing requirements.

NIEHS is also committed to efforts that replace, reduce, or refine (the “3Rs”) the use of animal models in studies. This concept of replacing, reducing, or refining animal use in research and testing was first described more than 65 years ago . The 3Rs became a tenet for the scientific community to address animal welfare in a meaningful way.

• Replacing: The method substitutes traditional animal models with non-animal systems such as computer models or biochemical or cell-based systems, or one animal species is replaced with a less developed one (for example, replacing a mouse with a worm).
• Reducing: The method decreases the number of animals required for testing to a minimum while still achieving testing objectives.
• Refining: The method eliminates pain or distress in animals, or enhances animal well-being, such as by providing better housing or enrichment.

Types of Alternative Methods

The scientific toolbox used for toxicological assessment continually expands. In a 2023 report, NIH categorized NAMs approaches into three general categories. Definitions and examples of each method are below.

In chemico: Experiments performed on biological molecules, such as proteins and DNA, outside of cells, which may be used to study how these molecules interact with each other and with drugs.

• Non-mammalian models, such as zebrafish , nematodes, and planaria , can enable the rapid and cost-effective assessment of the effects of chemicals on biology and behavior .

In silico: Experiments performed by computing platforms or custom hardware, encompassing mathematical modeling and simulation, machine learning, and other computational techniques.

• Computational model is a general term describing the use of computers to simulate complex systems, such as those that can be used as a NAM.
• Artificial intelligence and machine learning (AI/ML) approaches can enhance and support human intellect in assessing the safety of chemical exposures. For example, advanced computer simulations can be used to model biological processes and predict the effects of previously untested chemicals and drugs.

In vitro: Experiments performed on cells outside of the body, including various types of cell, organoid, and tissue culture techniques.

• These methods may involve culturing cells in the laboratory and can take advantage of high-throughput screening of large numbers of chemical compounds.
• Microphysiological systems or organs-on-chips are complex, cell-based devices that mimic key physiological aspects of tissues or organs by incorporating microenvironments that align with those in the human body. A particular system might incorporate flow and shear stress, appropriate pH and oxygen levels, biochemical and electrical stimuli, and other factors that replicate various features of animal-based models.
• Mini-organs or organoids are 3D tissue-like structures , derived from stem cells, that closely replicate the complexity and function of human organs. These tiny, artificially grown tissues contain various specialized cell types similar to those found in full-sized organs.

Different human populations experience different levels of susceptibility to toxic effects from chemical exposure, presenting a complex problem for chemical risk assessment. Alternative methods, such as those above, could provide more rapid and human-relevant techniques to assess chemical safety for diverse communities affected by environmental exposures. Alternatives to animal testing can be used for toxicological research, such as chemical safety and drug effectiveness testing, or other types of biomedical research that examine biological mechanisms of disease.

NIH leadership for NAMs

The NIH Common Fund’s Complement Animal Research In Experimentation program (Complement-ARIE) aims to speed the development, standardization, validation, and use of human-based NAMs. It will significantly advance the understanding of human health and disease and approaches to basic, translational, toxicological, and clinical research. NIEHS plays a lead role in planning activities for this program.

Complement-ARIE brings together many areas of expertise through a consortium of researchers in the following efforts:

• Technology centers will develop NAMs projects to fill in areas of greatest need. Projects will emphasize biological complexity, high throughput techniques, combining approaches, and data sharing.
• A resource coordinating center will create integrated data structures and a searchable NAMs repository.
• A validation and qualification network will accelerate deployment and regulatory approval of NAMs for biomedical research.
• Community engagement and training will promote the development of an inclusive and diverse biomedical research workforce with the skills to build and use new NAMs.
• Strategic engagement with key partners will advance opportunities in the development and use of NAMs in basic, translational, and clinical research.

NIEHS is committed to advancing new approaches to safety testing of chemicals and medical products in the United States and to the ethical and responsible conduct of necessary animal research.

• NIEHS leads the Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM), which coordinates the activities of 17 federal regulatory and research agencies to work together to develop and evaluate new, improved, and alternative test methods and strategies to replace, reduce, or refine animal use.
• NICEATM supports a range of computational toxicology projects that use mathematics, informatics, and computer models to better understand how to predict the toxic effects of chemicals.
• NICEATM helped develop an online data resource called the Integrated Chemical Environment (ICE) that supports the development, evaluation, and application of NAMs.
• In support of Complement-ARIE, NICEATM is conducting a landscape analysis of existing NAMs efforts in health and disease and supporting the validation and qualification network.
• The Scientific Advisory Committee on Alternative Toxicological Methods (SACATM) includes experts from academia, industry, and animal welfare organizations. The committee meets annually to advise the NIEHS director on the development, evaluation, and implementation of new approach methodologies undertaken by NICEATM and ICCVAM.

Additionally, the NIEHS Division of Translational Toxicology is part of the Toxicology in the 21st Century (Tox21) program, a federal research collaboration developing high-throughput tests and NAMs that can rapidly determine whether chemical  adversely affect human health.

For example, under Tox21, researchers at NICEATM developed the Tox21BodyMap to predict which organs in the human body may be affected by a chemical. The tool is based on data from 971 high-throughput screening assays that evaluated approximately 10,000 unique chemicals. The Tox21BodyMap will help scientists generate hypotheses to test and prioritize chemicals for toxicity testing.

Extramural research

NIEHS also funds a variety of projects to develop alternative testing methods through grants to external researchers and small businesses.

For example, NIEHS grantees from the Massachusetts Institute of Technology developed a new toxicity test that can accurately measure the impact of chemicals on cell survival in a matter of days. The findings could allow academic researchers and drug companies to rapidly evaluate environmental contaminants and new drugs for possible harmful effects.

Scientists supported by the NIEHS Superfund Research Program developed an innovative template-and-anchor model to determine the health effects of exposure to dioxins. Researchers used the model to combine publicly available data on exposures and on known health outcomes to assess the overall risk dioxins could pose to health. It is an example of how a computational approach can provide a promising novel approach methodology to predict health risks associated with chemical exposures.

Researchers partially funded by NIEHS developed an in-silico method–a computer simulation tool–for genetic research that may partially replace the need for genetically modified animals. Called the Gene Knockout Inference (GenKI), the tool allows scientists to simulate the relationship between genes in individual cells so they can study which genes affect cellular functions. Future refinements to the tool may enable its predictive power.

Stories from the Environmental Factor (NIEHS Newsletter)

• NIH Endorses Recommendations on Use of Non-animal Method (March 2024)
• Future Challenges in Reducing Animal Testing Assessed by Panel (November 2023)
• Impact of Variability in Animal Test Data Discussed by Kleinstreuer (January 2022)
• Agencies Advised on Reducing Animal Testing, Embracing Alternatives (November 2021)
• New Chemical Testing Approach Will Help to Replace Animal Use (August 2021)
• Animal Replacement Accomplishments Draw Broad Interest (July 2021)
• Computational Toxicology Featured in Special Journal Issue (March 2021)

Additional Resources

• Animals in NIH Research - Research with laboratory animals (also called “animal models”) has provided the foundation for safe and effective life-saving treatments for many diseases and conditions affecting humans. All federally funded research animals are protected by laws, regulations, and policies to ensure the smallest possible number are used to produce reliable results. NIH is committed to their proper care.
• Catalyzing the Development and Use of Novel Alternative Methods – The report of an NIH working group on NAMs (December 2023). NIH Director Monica Bertagnolli, M.D., accepted this working group’s recommendations and issued an NIH Statement on catalyzing the development of novel alternative methods (February 2024).
• ChemMaps is a publicly accessible web tool for exploring environmental chemicals and predicting their risk. The tool includes DrugMap, which lists more than 8,000 drugs, and EnvMap, which lists more than 47,000 chemicals of relevance to NIEHS and EPA.
• The Organisation for Economic Co-operation and Development (OCED) assists its 38 member countries, including the U.S., in developing and implementing policies and instruments that make systems for managing chemicals as efficient and robust as possible, while protecting human health and the environment. The Test Guidelines Programme advances alternatives to animal testing internationally. Data generated in one country using these methods are accepted in all member countries, reducing the need for redundant testing for regulatory authorities.

Related Health Topics

• Chemical Mixtures
• Exposure Science
• Gene and Environment Interaction

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Laika: The First Earthling in Space

The first Earthling was Laika, a Russian mongrel found on the streets of Moscow.

The first Earthling in space wasn’t human.  Not counting microbes, this first Earthling was a Russian mongrel found on the streets of Moscow. Laika the dog was launched into space on November 3rd, 1957, but didn’t make it back alive to enjoy her fame.  Officially, she ran out of oxygen. After the fall of the Soviet Union, it was revealed she died of stress and overheating. Afterwards, her craft, Sputnik II, disintegrated on reentering the atmosphere. “Laika” wasn’t even her actual name; it was Kudryavka, meaning Little Curly; in the U.S. she was sometimes known as Muttnik.

The U.S. had actually been the first nation to launch an animal towards space: in 1948, a rhesus monkey named Albert 1 was the payload on a captured German V-2 fired from White Sands, New Mexico. Unpublicized, Albert died of suffocation during the flight. But Laika made it into orbit alive, a historic feat, and became a cultural phenomenon. Recent poems by Charles Bennett and Patti White testify to Laika’s continuing place in collective memory.

In the space race, the U.S. preferred rhesus, squirrel, and pig-tailed monkeys, as well as chimpanzees, while the Russians worked with female dogs (they found that waste disposal was easier with the females.) These experimental subjects were used to see how humans might respond to spaceflight, particularly to the effects of radiation and weightlessness.

In the late 1960s, as humans approached the Moon, U.S. “space monkey” experiments continued; the man in charge of them, Dr. W. Ross Adey, was scathingly dismissive about earlier efforts, saying they “ scarcely warranted the name of an experiment. ”

Besides dogs and monkeys, other animals used in space experiments included mice, rats, rabbits, cats, turtles, fruit flies, frogs (eggs, tadpoles, adults), newts, fish, jellyfish, amoeba, and spiders. In the early 1960s, “ more than 15,000 animals a year ” were involved in space medicine research, most of it ground-based. The culmination of these tests was a 1998 space shuttle mission, which included over 2000 creatures, along with the seven human crew, who supervised 16 days of neurological testing. But the 1970s, animal deaths — particularly of mammals — in space exploration had become controversial .  The ethics of animal testing in space, as well as here on Earth, have been debated since.

So let’s remember this plucky mutt, trapped in what became her coffin 57 years ago. A human achievement at the expense of a non-human. Earthlings, bound together like the double star of Sirius, the Dog Star.

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The Moscow Signals Declassified Microwave Mysteries: Projects PANDORA and BIZARRE

National Security Archive Posts Special Declassified Collection on Microwave Transmissions Aimed at U.S. Moscow Embassy, 1953-1979 

Was the Moscow Signal a Historical Precedent for the "Havana Syndrome"?

Project BIZARRE: Pentagon Officials Conducted Radiation Tests on Monkeys, Planned Secret Human Experimentation

Washington D.C., September 13, 2022 - On the 5 th  anniversary of the CIA’s September 13, 2017, decision to pull its agents out of Cuba, after several operatives were stricken with what has become known as the “Havana Syndrome,” the National Security Archive today posted the first of a declassified documentation series on the “Moscow Signals”—a decades-long chapter of the Cold War during which Soviet intelligence bathed the U.S. Embassy in Moscow with microwave transmissions on a daily basis, and, in the late 1950s, penetrated the U.S ambassador’s residence with ionizing radiation. The records published   by the Archive are among those being reviewed by a special, high-level panel tasked by the Biden administration to search for clues into the enduring mystery surrounding cognitive brain traumas experienced by several dozen U.S. intelligence and diplomatic personnel in Havana, and elsewhere, over the last five years.

The CIA announced in late August that it is compensating at least a dozen of its officers and operatives for syndrome-related injuries known as “Anomalous Health Incidents” (AHI).

The documents posted today record Project BIZARRE, the actual—and rather appropriate—codename for a program of radiation experiments conducted on monkeys to determine if the Moscow Signal was intended to degrade the abilities of U.S. personnel to function at the Embassy. Project BIZARRE was a highly classified component of Project PANDORA, a broader research effort undertaken by the Defense Department’s Advanced Research Projects Agency (ARPA) that included evaluating blood samples of U.S. personnel posted in Moscow and surveying medical records of crew members of the aircraft carrier USS Saratoga to determine if exposure to radiation-emitting technology on board produced physiological effects.

“The Soviets have reported in the open literature that humans subjected to low-level (non-thermal) modulated microwave radiation, show adverse clinical and physiological effects,” ARPA official Richard Cesaro reported in a TOP SECRET, September 1967, update on Project BIZARRE. “The ARPA BIZARRE program will establish methods which should permit us to relate the behavior of sub-human primates to man under conditions of microwave exposure. This may require direct testing with humans under controlled conditions.” 

Among the documents posted today is the original TOP SECRET “Justification Memorandum for Project Pandora,” written by Cesaro in October 1965, which stated that the White House had ordered a program of “intensive investigative research” “under the code name project ‘TUMS’’—Technical Unidentified Moscow Signal. The posting also includes a SECRET May 1965 memorandum by ARPA scientist Samuel Koslov which argued that “a program to specifically check the complex Moscow signal waveforms on higher primates should be carried out to supply some data base for possible use in a protest action” against the Kremlin. Titled “Biomedical Phenomena,” the memo was obtained by science historian Nicholas H. Steneck for his groundbreaking 1984 study, The Microwave Debate , but has never been published in full on the Internet before now.

OVERVIEW OF THE MOSCOW SIGNAL

Despite four years of efforts, the multi-million-dollar PANDORA-BIZARRE projects failed to prove the early hypothesis that the Russians deployed the microwave beams to degrade the mental and physical abilities of U.S. Embassy officers to perform their diplomatic and intelligence duties. An initial experiment of modulated microwave beams on a single monkey appeared to show an impact on its behavior. But the test was conducted using the CIA’s inaccurate readings that the power of the beams was .5 to one milliwatt—exceeding Soviet safety levels by a factor of 100. In reality, as the CIA correctly determined in 1967, the power density of the beams was "no greater than .05 mw/cm in the Moscow Signal," a level that was well below U.S. and Soviet safety levels, as ARPA official Cesaro advised in a TOP SECRET update on Project BIZARRE from September 1967. At the corrected levels, he reported, the “modulated microwave radiation did not cause the primate to degrade in conducting his work tasks.”

The findings, according to one CIA scientist working with ARPA, indicated that the beams were not dangerous to U.S. personnel at the Embassy. “I feel confident in stating,” as Joe Johnston reported in September 1967 on Project BIZARRE results, “that, at the power levels reported for TUMS, persons exposed are at no risk of injury.”

Another theory pursued by the U.S. intelligence community suggested that the signal served as a jamming device intended to disrupt U.S. espionage operations that were conducted out of a surveillance shed on the roof of the Embassy building. A third, and prevalent, theory is that Soviet intelligence agencies employed the Moscow Signal to activate, power and/or interpret eavesdropping devices in the walls of the Embassy building. “Defense feels we must bear in mind the possibility that some of the signals are [deleted] for the activation or interrogation of audio devices implanted in the Embassy,” stated a TOP SECRET/SENSITIVE White House memorandum for President Ford in February 1976, drawing on the Defense Department’s evaluation of the microwave beams. [Note: The memorandum to President Ford will be posted on September 15.] 

Numerous such bugging devices were discovered in April 1964, hidden in the walls of at least eleven Embassy offices—including the office of the U.S. Defense Attaché. The realization that Soviet intelligence had penetrated the Embassy and compromised secret U.S. communications set in motion a series of countersurveillance measures and a major focus on the mysterious energy beam directed at the building. U.S. technicians first detected the energy rays in 1953, shortly after the Embassy opened, but only began to actively monitor the radiation rays in the early 1960s. A technician from the State Department’s Bureau of Diplomatic Security, Maclyn Musser, identified them as microwave radiation and reported, in 1963, that the beam was 50 feet across. “More effort should be made to understand the purpose of the microwave signal directed at the Embassy, or failing in this, to stop it,” Jerome Wiesner, the former chairman of the White House Science Advisory Board advised in a SECRET June 1964 memo on “Bugging of U.S. Embassy, Moscow”—the first document posted today as part of the Moscow Signal collection. “It is hard to understand why we have been so unconcerned about it.”

As the declassified documents posted today record, in the mid-1960s, U.S. national security agencies initiated a series of programs, assessments and operations designed to address the microwave beams, codenamed “TUMS”—Technical Unidentified Moscow Signal. (In the mid-1970s, after a second signal was detected, the codename was upgraded to “MUTS”—Moscow Unidentified Technical Signals.) The Pentagon conducted the Project PANDORA and BIZARRE studies. Those included:

Project Big Boy : A set of medical evaluations of the personnel aboard the Navy’s aircraft carrier Saratoga . ARPA, according to one status report, would place “observers aboard the Saratoga to get base line [sic] readings on selected members of the crew.” The purpose of Project Big Boy was to evaluate physical and mental differences between distinct groups of crewmen: veteran members of the crew whose duties exposed them to microwaves generated by radar instrumentation; newer recruits with no history of previous exposure to microwaves; sailors who were detailed above deck; and others below deck. The study produced no discernible evidence of physiological and psychological differences between the test groups.

The Monkey Experiments : Between 1966 and 1969, ARPA teams conducted and contracted for a series of radiation experiments on chimps and rhesus monkeys, compiling data on behavior modification, heart rates, and tissue and blood analysis, among other physiological elements. (Initially codenamed PANDORA, after the first set of experiments, the primate tests were given their own specific codename—Project BIZARRE.) As members of the ARPA team disagreed on whether the tests had produced any conclusive evidence of radiation exposure on health and behavior, the experiments were sent for outside peer review. One review from the RAND Corporation concluded that “the data do not present any evidence of a behavioral change due to the presence of the special signal within the limits of any reasonable scientific criteria.” Another RAND Corp evaluation of a specific set of experiments noted that it had produced “no material…which is scientifically credible” of any impact. In addition, “animal care was not in accordance with good laboratory practice,” the RAND panel reported. “Examination of the data log indicated that of five monkeys’ deaths, three were certainly due to strangulation resulting from poor experimental design of the restraint system.”

Planning for Human Experimentation : Declassified summaries of the meetings of the PANDORA program’s Science Advisory Committee record preparations to go beyond primate experimentation and use unwitting human subjects who would not be aware of the nature of the radiation tests. Subjects for human testing of radiation impact would be secured from Fort Detrick and subjected to radiation exposure over a period of six months, according to the discussion at an April 1969 meeting. “Study should be double-blind with protection of eyes and gonads,” Committee members suggested. “Shielding of testicles is recommended.” Before any such experiments could be performed, however, the PANDORA/BIZARRE program was shut down in 1970.

The State Department also played a role in the TUMS inquiry, commissioning George Washington University’s Human Cytogenetics Research Laboratory to conduct a SECRET study, “Cytogenetic Evaluation of Mutagen Exposure.” The study gathered, coded and analyzed blood samples taken under false pretenses from U.S. personnel posted in Moscow. They were told that the State Department Medical Office was monitoring the spread of Russian viruses. Publicly, the research was given the innocuous title: “The Moscow Viral Study.”

Among other countersurveillance measures that remain highly classified, the CIA monitored the signal and, in 1965, sent a special technician to evaluate security at the Embassy. He recommended installing thin shields on the Embassy windows to block the radiation beams from entering the building—a recommendation that went unimplemented for more than a decade, according to documents obtained by the Associated Press .

U.S. officials also undertook efforts to convince the Soviet leadership to shut off the signal. The first high-level effort took place at a June 1967 superpower summit held in Glassboro, N.J., between U.S. President Lyndon Johnson and Soviet Premier Alexei Kosygin. At a side meeting, Secretary of State Dean Rusk told Soviet foreign minister Andrei Gromyko that “we were very much concerned at an electro-magnetic signal directed at our Chancery building in Moscow.” “We did not know the purpose of this activity,” Rusk said, according to a declassified memorandum of conversation, but the U.S. wanted “the matter to be investigated and the activity stopped.” In response, Soviet ambassador Anatoly Dobrynin suggested that the U.S. was conducting “similar activity” against the Soviet Mission in New York and the Soviet Embassy in Washington. While expressing skepticism at the U.S. claims—which were, in fact, incorrect—that the radiation exceeded Soviet safety standards, Gromyko “indicated he would look into the matter.”

But the daily doses of radiation continued. By mid-1975, U.S. intelligence monitors detected additional, and stronger, signals aimed at the Embassy. Hundreds of diplomats, security and intelligence officers, and their families who lived in the residence section of the Consulate building, were unknowingly exposed to radiation for up to 19 hours a day.

The U.S. ambassador, Walter Stoessel, became the unsung hero of the Moscow Signal saga in the fall of 1975 when he forcefully pushed a reluctant Secretary of State, Henry Kissinger, to pressure the Kremlin to terminate the transmissions and to authorize a classified briefing for the Embassy staff—who had been kept in the dark about the existence of the Moscow Signal. A strictly confidential Embassy staff briefing was scheduled in early February 1976, cancelled, and then rescheduled and held. Sensitive information Stoessel shared with U.S. Embassy personnel immediately leaked to U.S. newspapers, setting off a major scandal in U.S.-Soviet relations. 

AN INCOMPLETE HISTORICAL RECORD

The publicity surrounding the Moscow Signal generated congressional inquiries and hearings and renewed internal U.S. government efforts to halt the transmissions. The National Security Agency eventually sent one of its leading technical officers, Charles Gandy, to Moscow to assess Embassy security and to determine how the microwave beams were being used to intercept U.S. Embassy communications and identify U.S. spies in Russia. Gandy’s investigation became the focus of a recent book, The Spy in Moscow Station,  by former NSA official Eric Haseltine.

But the intelligence operations and assessments produced by the NSA and CIA on the Moscow Signal remain TOP SECRET. “Information on nonbiological testing that followed the discovery of the Moscow signal is still classified,” Professor Steneck noted in his book, The Microwave Debate , which contained several detailed chapters on the microwave beams and the U.S. government response when it was published in 1984. After nearly four decades, almost none of the intelligence community’s records on the Moscow Signal have been released.

Pursuant to demands by Congress, however, the U.S. government did begin to declassify select parts of the history of U.S. efforts to understand and address the Moscow Signal. ARPA declassified some documentation for a 1979 investigation by the Senate Committee on Commerce, Science, and Transportation. Other records were obtained through the Freedom of Information Act (FOIA) by Steneck while researching his book. In the mid-1980s, the Associated Press used the FOIA to obtain several thousand pages of records. An investigative reporter named Michael Drosnin also obtained numerous PANDORA documents under the FOIA but never published the information they contained. Some of the PANDORA documents were eventually posted on a Pentagon website and later used by former Foreign Policy executive editor Sharon Weinberger in her book, Imagineers of War: The Untold Story of DARPA, the Pentagon Agency That Changed the World . The book was excerpted in an article for the Foreign Policy website, “The Secret History of Diplomats and Invisible Weapons,” that noted that the alleged use of a “sound weapon” against U.S. Embassy officials in Cuba “harks back to a Cold War medical mystery” in Russia. Former U.S. diplomats who were exposed to the Moscow Signal in the 1970s—especially those who believe their rare blood cancer illnesses derive from that exposure—have also written about the parallels with the "Havana Syndrome." “It is like ‘déjà vu’ all over again,” said retired diplomat James Schumacher, who was posted in Moscow over 40 years ago and wrote in an article for the American Foreign Service Association titled “Before Havana Syndrome, There Was Moscow Signal.”

The National Security Archive obtained the declassification of phone conversations between Henry Kissinger and Soviet Ambassador Anatoly Dobrynin relating to the Moscow Signal through the FOIA and has located dozens of reports on PANDORA/BIZARRE—along with diplomatic cables and reports relating to the diplomacy with the Kremlin to end the microwave beams—in the files of the National Archives and various presidential libraries. The Archive will continue to use the FOIA to uncover the full historical record on this episode, including the CIA assessments and the still secret records on how Washington and the Kremlin negotiated an end to the microwave transmissions.

Part II of the series,  “The Moscow Signals Declassified: Microwave Diplomacy,”  which records more than ten years of back channel diplomatic efforts to address the radiation beams aimed at the Embassy, will be posted on September 15, 2022. Part III,  “Irradiating Richard Nixon,”  which documents ionizing radiation detected during the Vice President's 1959 trip to Moscow, will be posted the week of September 19th. A supplementary, special collection of documentation on “Moscow Signals Declassified,” will also be posted the week of September 19.

Acknowledgements : The National Security Archive respectfully thanks Nicholas Steneck for his original, groundbreaking research on the Moscow Signal, and for his support and encouragement on this project; and also Louis Slesin for his assistance. Thanks also to Jacqueline Schluger, George Washington University, for research assistance on this posting.

The Documents

National Security Archive, John Prados and Arturo Jimenez-Bacardi, eds., “Understanding the CIA,” Document 14

In the wake of the discovery of 17 Soviet listening devices hidden in the walls of U.S. Embassy in Moscow in June 1964, the chairman of the President’s Scientific Advisory Committee, MIT Provost Jerome Wiesner, conducted a security review of the Embassy. His classified report to Clark Clifford, who chaired the President’s Foreign Intelligence Advisory Board (PFIAB), contains a number of recommendations, among them using headsets and microphones to conduct secure conversations in the building, “inducing masking sounds” into the walls to disable the function of the eavesdropping equipment, and mounting screens to block electromagnetic-reflection surveillance operations. Wiesner also sounds the alarm on the microwave radiation beams that have been bathing the building for a decade: “More effort should be made to understand the purpose of the microwave signal directed at the Embassy, or failing in this, to stop it,” he advised. “It is hard to understand why we have been so unconcerned about it.”

Nicholas H. Steneck personal collection

In one of the earliest arguments in favor of conducting experiments to explain the Moscow Signal, scientist Samuel Koslov of the Defense Department’s Advanced Research Projects Agency (ARPA) sends a memo to the State Department’s security office with a brief overview, based on Soviet scientific literature, of the “possible effects of low level continuous exposure” to radiation on human health. “A possible explanation of the Moscow Signal may reside in an attempt to produce a relatively low level neurophysiological condition among Embassy personnel,” Koslov postulates, while admitting that “the detailed studies of the signal do not give this a high probability of interest.” Koslov insists, erroneously, that “the Soviet irradiation of the Embassy exceeds their own ambient safety level by a factor of 100.” (Initially, U.S. intelligence significantly overestimated the strength of the signal when, in fact, it was well below both Soviet and U.S. safety standards.) He advocates for “a program to specifically check the complex Moscow signal waveform on higher primates” in order to “supply some data base for possible use in a protest action.” Within a few months, ARPA receives authorization to initiate a secret program to test the impact of radiation exposure on the behavior of monkeys.

Drosnin FOIA, DoD Reading Room

ARPA initiates a special research program codenamed “Project PANDORA.” In this memorandum introducing the project, supervisor Richard Cesaro explains that the U.S. Embassy in Moscow has been radiated with low-level electromagnetic beams on a continuous basis for a number of years. In response, the White House has ordered the U.S. Intelligence Board to assure that “intensive investigative research be conducted within the State Department, CIA and DOD to attempt to determine what the actual threat is and stop it.” The code name for the multi-agency efforts is “TUMS”–Technically Unidentified Moscow Signal. But, Cesaro advises, the ARPA contribution “is known as Project PANDORA” and will address “one of the potential threats, that of radiation effects on man.” Cesaro informs the other agencies participating in the project that a “program has been outlined to irradiate a group of primates under carefully controlled conditions simulating the dosages and complex modulation of the threat.” Cesaro adds that, “The trained primates will be carefully observed under varying and controlled irradiated conditions in an attempt to determine if any changes in their behavior or physiological condition can be detected.” Eventually, as ARPA expands its work on the Moscow Signal, the experiments on rhesus monkeys will be referred to as “Project BIZARRE.”

Nicholas Steneck research papers, Gerald Ford Presidential Library

The State Department’s medical office cables the U.S. Embassy in Moscow to advise them of the “Moscow Viral Study” that the department is conducting as a cover story to draw blood from U.S. personnel to research the physiological effects of the Moscow Signal. To identify potential subjects, the Department requests quarterly reports on employees and dependents who are due to return from Moscow to the U.S. for home leave.

The State Department medical office offers George Washington University an 11-month contract to evaluate and code blood samples taken from Moscow Embassy diplomats, employees, and dependents. The project is titled “Cytogenetic Evaluation of Mutagenic Exposure” and will be supervised by Dr. Cecil Jacobson, a George Washington University scientist assigned to the Human Cytogenetics Research Laboratory who is on the PANDORA team. In a reference to PANDORA, a summary of the contract states that the human blood samples may inform experimentation on animals. “Confirmative animal experiments will be undertaken later,” states a summary of the program.

U.S. National Archives, Department of State Records (RG 59), Subject Numeric Files, 1967-1969, BG Moscow 13

During the June 1967 Summit between President Lyndon Johnson and Soviet Premier Alexei Kosygin, U.S. officials issue the first high-level protest of the ongoing microwave signals. At a side meeting between Secretary of State Dean Rusk and Soviet Foreign Minister Andrei Gromyko, Rusk stated that “we were very much concerned at an electro-magnetic signal directed at our Chancery building in Moscow.” Rusk said the U.S. “did not know the purpose of this activity,” but said the U.S. wanted “the matter to be investigated and the activity stopped.” In response, Soviet Ambassador Anatoly Dobrynin suggested that the U.S. was conducting “similar activity” against the Soviet Mission in New York and the Soviet Embassy in Washington. While expressing skepticism at the U.S. claims, Gromyko “indicated he would look into the matter.”

In a special summary to a colleague, the CIA’s representative on Project PANDORA/BIZARRE, Joseph Johnston, records the status of the experiments. He notes that analysis of the “TUMS power levels” has been revised and considerably lowered. There is now “reasonable certainty that the power level is not over 50 microwatts/cm2” but closer to 2 microwatts/cm2 at its average high level. Citing the results of the first test on a monkey (which were conducted when U.S. analysts mistakenly believed the signal was at a higher power level than it was) Johnston notes that there were “pronounced behavioral affects [and] performance decrement.” The impact on behavior, he suggests, was “due to the modulation feature” of the signal, “and not to the energy bearing carrier frequency.” “This very intriguing and important observation in one animal must be pursued,” he advises, and confirmed by an independent laboratory. Johnston emphasizes that “all positive findings of Project BIZARRE were achieved at one half an order of magnitude below the accepted U.S. standard for safe exposure.” Moreover, subsequent experiments at the adjusted lower level of radiation “produced no behavioral effects,” Johnston points out. He concludes: “I feel confident in stating that, at the power levels reported for TUMS, persons exposed are at no risk of injury.”

Ricard S. Cesaro, overseer of the PANDORA/BIZARRE program, sends a “progress report on Project BIZARRE” to the ARPA research and engineering director in September 1967. His report references a series of previous updates on subjecting primates to microwave exposure, as well as a secret CIA memorandum titled “Summary of TUMS Power Density Measurements” which reported that the levels of the microwaves beamed at the U.S. Embassy were considerably lower than previously believed. (They were, in fact, at levels below the Soviet safety standards, and likely not threatening to human health.) [1] “New measurements with ARPA instrumentation of the ‘Moscow Signal’ on site has [sic] now been completed,” Cesaro advises. Using the corrected level, “the recent BIZARRE tests have completed one experiment on primate behavior” that demonstrates “no overt primate performance degradation …” Even so, Cesaro’s memo lays out the argument to go beyond radiation experiments on monkeys and conduct tests on human subjects. “The ARPA BIZARRE program will establish methods which should permit us to relate the behavior of sub-human primates to man under conditions of microwave exposure,” he advises. “This may require direct testing with humans under controlled conditions.”

ARPA official Herbert Pollack reports on a meeting held on the USS Saratoga aircraft carrier with key naval officers to discuss a new PANDORA project. The project will review medical records of the ship’s personnel, and place “observers aboard the Saratoga to get base line readings on selected members of the crew.” The purpose of the study is to evaluate medical differences between distinct groups of crewmen: veteran members of the crew whose duties exposed them to microwaves generated by radar instrumentation; and new recruits with no history of previous exposure to microwaves. At ARPA, the project is code-named operation “Big Boy.”

Document 10

In one of a series of monthly meetings in 1969, Pandora’s scientific-government board reviews its research efforts on the Moscow Signal. The first part of the meeting covers the initial results of project “Big Boy,” the study of the crew of the USS Saratoga . Early tests “were negative,” finding “no significant differences in psychological tests performed on apparently exposed and control groups,” and no “significant differences” in genetic and physical findings. After almost four years of experiments on monkeys, the panel agrees that “there is at present insufficient evidence to draw conclusions” about the potential impact of the Moscow Signal on human behavior. The inconclusive nature of the research reinforces proposals at the meeting to move beyond exposing monkeys to radiation to “develop[ing] a human program.” Subjects for human testing of radiation impact could be secured from Fort Detrick (misspelled as “Ft. Dietrich” in the document) and subjected to radiation exposure over a period of six months, according to the discussion. “Study should be double-blind with protection of eyes and gonads,” the board suggests. “Shielding of testicles is recommended.”

Document 11

The PANDORA officials devote most of this meeting to developing a specific protocol for subjecting humans to radiation tests, addressing the levels of radiation to be used, and the “behavioral aspects of the program.” They also discuss “classification considerations” and “an appropriate cover” story to maintain secrecy around the research, including from the personnel being subjected to the tests. “DOD regards the general line of effort to acquire human-based data on effects of the signal, with appropriate safeguards, as a high priority,” the minutes state. “ARPA believes that the entire effort should be classified for several reasons.” Reflecting the sensitivity around the issue of human testing, according to the minutes “It was urged that DOD provide written security specifications and guide for the program.” (Emphasis in original.)

Document 12

Drosnin FOIA, DOD Reading Room

RAND Corp. scientist Samuel Koslov, the former ARPA official who in 1965 who helped initiate the PANDORA project, assesses the data generated by several years of experiments on the impact of radiation on the behavior of rhesus monkeys. “I am forced to conclude that the data do not present any evidence of a behavioral change due to the presence of the special signal within the limits of any reasonable scientific criteria,” he writes. “There is evidence of behavioral change in some cases but this change could be attributed to a variety of causes or systematic measurement errors all well within the limits of experimental methodology. Evidence of other effects such as EEG, histology, and chromosomal analyses have not accumulated with either adequate detail or control to tell whether effects due to radiation are present.”

Document 13

U.S. National Archives, Record Group 46, Records of U.S. Senate Committee on Commerce, Science and Transportation, 90 to 95th Congress, Project Pandora Folder

In response to a request from the Navy, a panel of experts led by RAND Corporation scientist Samuel Koslov evaluates one of the last Project BIZARRE-type contracts for radiation experimentation on monkeys and rabbits. The panel concludes that the leading experiments to measure the impact of “long-term, low-level chronic exposure of primates” to radiation have produced “no material … which is scientifically credible ….” Among the factors the panel cites are the failure of the Navy to provide proper radiation devices, bad management, poorly trained technicians, and “poor” animal care. “Animal care was not in accordance with good laboratory practice,” the panel reported, citing the death of five of the monkeys. “Examination of the data log indicated that of five monkeys’ deaths, three were certainly due to strangulation resulting from poor experimental design of the restraint system.”

Document 14

In the aftermath of the scandal over the Moscow Signal, and publication of a high-profile article on the subject in The New Yorker magazine by Paul Broduer, several congressional committees investigate U.S. government efforts to address the microwave beams, including the PANDORA and BIZARRE projects at DARPA. In response to a series of questions posed by Representative Warren Magnuson, chairman of the House Committee on Commerce, Science and Transportation, DARPA director George H. Heilmeier transmits this letter providing answers and a general summary of the PANDORA program. Among the details: PANDORA was shut down in March 1970 after almost five years of work; its total costs amounted to $4,615,000. Heilmeier misleads the committee by denying that PANDORA was intended to “probe” the use of microwaves as a form of “mind control.” He also states that DARPA “does not foresee the development, by DARPA, of weapons using microwaves and actively being directed toward altering nervous system function or behavior. Neither are we aware of any of our own forces or possible adversary forces developing such weapons.” In the letter, Heilmeier also announces that meeting minutes of the PANDORA board have been declassified.

Document 15

U.S. Senate Committee Print

Following the scandal of the Moscow Signal, the Senate Committee on Commerce, Science, and Transportation conducts a lengthy review of the documentation on the PANDORA/BIZARRE projects and of various official investigations in an effort to determine the health and safety effects on U.S. personnel who served at the Embassy. This staff report criticizes the official secrecy that kept U.S. personnel in the dark about the ongoing radiation: “Embassy employees were not informed by the State Department of the presence of this radiation throughout the period from its initial discovery until early 1976,” the report notes. “The employees should have been promptly informed of the situation.” At the same time, the report concludes that as of 1979 the medical survey studies on U.S. personnel showed no discernible evidence of impact on health from exposure to the low-level radiation beams. “No convincing evidence was discovered that could directly implicate the exposure to microwave radiation experienced by the employees at the Moscow Embassy in the causation of any adverse health effects as of the time of this analysis,” the Senate inquiry concluded, with the caveat that “it is too early to have been able to detect long-term mortality effects” among hundreds of U.S. personnel exposed to radiation waves between 1953 and 1977.

[1] See also Nicholas Steneck, The Microwave Debate (Cambridge: MIT Press, 1985), 110.

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72 Easy Science Experiments Using Materials You Already Have On Hand

Because science doesn’t have to be complicated.

If there is one thing that is guaranteed to get your students excited, it’s a good science experiment! While some experiments require expensive lab equipment or dangerous chemicals, there are plenty of cool projects you can do with regular household items. We’ve rounded up a big collection of easy science experiments that anybody can try, and kids are going to love them!

Easy Chemistry Science Experiments

Easy physics science experiments, easy biology and environmental science experiments, easy engineering experiments and stem challenges.

1. Taste the Rainbow

Teach your students about diffusion while creating a beautiful and tasty rainbow! Tip: Have extra Skittles on hand so your class can eat a few!

Learn more: Skittles Diffusion

2. Crystallize sweet treats

Crystal science experiments teach kids about supersaturated solutions. This one is easy to do at home, and the results are absolutely delicious!

Learn more: Candy Crystals

3. Make a volcano erupt

This classic experiment demonstrates a chemical reaction between baking soda (sodium bicarbonate) and vinegar (acetic acid), which produces carbon dioxide gas, water, and sodium acetate.

Learn more: Best Volcano Experiments

4. Make elephant toothpaste

This fun project uses yeast and a hydrogen peroxide solution to create overflowing “elephant toothpaste.” Tip: Add an extra fun layer by having kids create toothpaste wrappers for plastic bottles.

5. Blow the biggest bubbles you can

Add a few simple ingredients to dish soap solution to create the largest bubbles you’ve ever seen! Kids learn about surface tension as they engineer these bubble-blowing wands.

Learn more: Giant Soap Bubbles

6. Demonstrate the “magic” leakproof bag

All you need is a zip-top plastic bag, sharp pencils, and water to blow your kids’ minds. Once they’re suitably impressed, teach them how the “trick” works by explaining the chemistry of polymers.

Learn more: Leakproof Bag

7. Use apple slices to learn about oxidation

Have students make predictions about what will happen to apple slices when immersed in different liquids, then put those predictions to the test. Have them record their observations.

Learn more: Apple Oxidation

8. Float a marker man

Their eyes will pop out of their heads when you “levitate” a stick figure right off the table! This experiment works due to the insolubility of dry-erase marker ink in water, combined with the lighter density of the ink.

Learn more: Floating Marker Man

9. Discover density with hot and cold water

There are a lot of easy science experiments you can do with density. This one is extremely simple, involving only hot and cold water and food coloring, but the visuals make it appealing and fun.

Learn more: Layered Water

10. Layer more liquids

This density demo is a little more complicated, but the effects are spectacular. Slowly layer liquids like honey, dish soap, water, and rubbing alcohol in a glass. Kids will be amazed when the liquids float one on top of the other like magic (except it is really science).

Learn more: Layered Liquids

11. Grow a carbon sugar snake

Easy science experiments can still have impressive results! This eye-popping chemical reaction demonstration only requires simple supplies like sugar, baking soda, and sand.

Learn more: Carbon Sugar Snake

12. Mix up some slime

Tell kids you’re going to make slime at home, and watch their eyes light up! There are a variety of ways to make slime, so try a few different recipes to find the one you like best.

13. Make homemade bouncy balls

These homemade bouncy balls are easy to make since all you need is glue, food coloring, borax powder, cornstarch, and warm water. You’ll want to store them inside a container like a plastic egg because they will flatten out over time.

Learn more: Make Your Own Bouncy Balls

14. Create eggshell chalk

Eggshells contain calcium, the same material that makes chalk. Grind them up and mix them with flour, water, and food coloring to make your very own sidewalk chalk.

Learn more: Eggshell Chalk

15. Make naked eggs

This is so cool! Use vinegar to dissolve the calcium carbonate in an eggshell to discover the membrane underneath that holds the egg together. Then, use the “naked” egg for another easy science experiment that demonstrates osmosis .

Learn more: Naked Egg Experiment

16. Turn milk into plastic

This sounds a lot more complicated than it is, but don’t be afraid to give it a try. Use simple kitchen supplies to create plastic polymers from plain old milk. Sculpt them into cool shapes when you’re done!

17. Test pH using cabbage

Teach kids about acids and bases without needing pH test strips! Simply boil some red cabbage and use the resulting water to test various substances—acids turn red and bases turn green.

Learn more: Cabbage pH

18. Clean some old coins

Use common household items to make old oxidized coins clean and shiny again in this simple chemistry experiment. Ask kids to predict (hypothesize) which will work best, then expand the learning by doing some research to explain the results.

Learn more: Cleaning Coins

19. Pull an egg into a bottle

This classic easy science experiment never fails to delight. Use the power of air pressure to suck a hard-boiled egg into a jar, no hands required.

Learn more: Egg in a Bottle

20. Blow up a balloon (without blowing)

Chances are good you probably did easy science experiments like this when you were in school. The baking soda and vinegar balloon experiment demonstrates the reactions between acids and bases when you fill a bottle with vinegar and a balloon with baking soda.

21 Assemble a DIY lava lamp

This 1970s trend is back—as an easy science experiment! This activity combines acid-base reactions with density for a totally groovy result.

22. Explore how sugary drinks affect teeth

The calcium content of eggshells makes them a great stand-in for teeth. Use eggs to explore how soda and juice can stain teeth and wear down the enamel. Expand your learning by trying different toothpaste-and-toothbrush combinations to see how effective they are.

Learn more: Sugar and Teeth Experiment

23. Mummify a hot dog

If your kids are fascinated by the Egyptians, they’ll love learning to mummify a hot dog! No need for canopic jars , just grab some baking soda and get started.

24. Extinguish flames with carbon dioxide

This is a fiery twist on acid-base experiments. Light a candle and talk about what fire needs in order to survive. Then, create an acid-base reaction and “pour” the carbon dioxide to extinguish the flame. The CO2 gas acts like a liquid, suffocating the fire.

25. Send secret messages with invisible ink

Turn your kids into secret agents! Write messages with a paintbrush dipped in lemon juice, then hold the paper over a heat source and watch the invisible become visible as oxidation goes to work.

Learn more: Invisible Ink

26. Create dancing popcorn

This is a fun version of the classic baking soda and vinegar experiment, perfect for the younger crowd. The bubbly mixture causes popcorn to dance around in the water.

27. Shoot a soda geyser sky-high

You’ve always wondered if this really works, so it’s time to find out for yourself! Kids will marvel at the chemical reaction that sends diet soda shooting high in the air when Mentos are added.

Learn more: Soda Explosion

28. Send a teabag flying

Hot air rises, and this experiment can prove it! You’ll want to supervise kids with fire, of course. For more safety, try this one outside.

Learn more: Flying Tea Bags

29. Create magic milk

This fun and easy science experiment demonstrates principles related to surface tension, molecular interactions, and fluid dynamics.

Learn more: Magic Milk Experiment

30. Watch the water rise

Learn about Charles’s Law with this simple experiment. As the candle burns, using up oxygen and heating the air in the glass, the water rises as if by magic.

Learn more: Rising Water

31. Learn about capillary action

Kids will be amazed as they watch the colored water move from glass to glass, and you’ll love the easy and inexpensive setup. Gather some water, paper towels, and food coloring to teach the scientific magic of capillary action.

Learn more: Capillary Action

32. Give a balloon a beard

Equally educational and fun, this experiment will teach kids about static electricity using everyday materials. Kids will undoubtedly get a kick out of creating beards on their balloon person!

Learn more: Static Electricity

33. Find your way with a DIY compass

Here’s an old classic that never fails to impress. Magnetize a needle, float it on the water’s surface, and it will always point north.

Learn more: DIY Compass

34. Crush a can using air pressure

Sure, it’s easy to crush a soda can with your bare hands, but what if you could do it without touching it at all? That’s the power of air pressure!

35. Tell time using the sun

While people use clocks or even phones to tell time today, there was a time when a sundial was the best means to do that. Kids will certainly get a kick out of creating their own sundials using everyday materials like cardboard and pencils.

Learn more: Make Your Own Sundial

36. Launch a balloon rocket

Grab balloons, string, straws, and tape, and launch rockets to learn about the laws of motion.

37. Make sparks with steel wool

All you need is steel wool and a 9-volt battery to perform this science demo that’s bound to make their eyes light up! Kids learn about chain reactions, chemical changes, and more.

Learn more: Steel Wool Electricity

38. Levitate a Ping-Pong ball

Kids will get a kick out of this experiment, which is really all about Bernoulli’s principle. You only need plastic bottles, bendy straws, and Ping-Pong balls to make the science magic happen.

39. Whip up a tornado in a bottle

There are plenty of versions of this classic experiment out there, but we love this one because it sparkles! Kids learn about a vortex and what it takes to create one.

Learn more: Tornado in a Bottle

40. Monitor air pressure with a DIY barometer

This simple but effective DIY science project teaches kids about air pressure and meteorology. They’ll have fun tracking and predicting the weather with their very own barometer.

Learn more: DIY Barometer

41. Peer through an ice magnifying glass

Students will certainly get a thrill out of seeing how an everyday object like a piece of ice can be used as a magnifying glass. Be sure to use purified or distilled water since tap water will have impurities in it that will cause distortion.

Learn more: Ice Magnifying Glass

42. String up some sticky ice

Can you lift an ice cube using just a piece of string? This quick experiment teaches you how. Use a little salt to melt the ice and then refreeze the ice with the string attached.

Learn more: Sticky Ice

43. “Flip” a drawing with water

Light refraction causes some really cool effects, and there are multiple easy science experiments you can do with it. This one uses refraction to “flip” a drawing; you can also try the famous “disappearing penny” trick .

Learn more: Light Refraction With Water

44. Color some flowers

We love how simple this project is to re-create since all you’ll need are some white carnations, food coloring, glasses, and water. The end result is just so beautiful!

45. Use glitter to fight germs

Everyone knows that glitter is just like germs—it gets everywhere and is so hard to get rid of! Use that to your advantage and show kids how soap fights glitter and germs.

Learn more: Glitter Germs

46. Re-create the water cycle in a bag

You can do so many easy science experiments with a simple zip-top bag. Fill one partway with water and set it on a sunny windowsill to see how the water evaporates up and eventually “rains” down.

Learn more: Water Cycle

47. Learn about plant transpiration

Your backyard is a terrific place for easy science experiments. Grab a plastic bag and rubber band to learn how plants get rid of excess water they don’t need, a process known as transpiration.

Learn more: Plant Transpiration

48. Clean up an oil spill

Before conducting this experiment, teach your students about engineers who solve environmental problems like oil spills. Then, have your students use provided materials to clean the oil spill from their oceans.

Learn more: Oil Spill

49. Construct a pair of model lungs

Kids get a better understanding of the respiratory system when they build model lungs using a plastic water bottle and some balloons. You can modify the experiment to demonstrate the effects of smoking too.

Learn more: Model Lungs

50. Experiment with limestone rocks

Kids  love to collect rocks, and there are plenty of easy science experiments you can do with them. In this one, pour vinegar over a rock to see if it bubbles. If it does, you’ve found limestone!

Learn more: Limestone Experiments

51. Turn a bottle into a rain gauge

All you need is a plastic bottle, a ruler, and a permanent marker to make your own rain gauge. Monitor your measurements and see how they stack up against meteorology reports in your area.

Learn more: DIY Rain Gauge

52. Build up towel mountains

This clever demonstration helps kids understand how some landforms are created. Use layers of towels to represent rock layers and boxes for continents. Then pu-u-u-sh and see what happens!

Learn more: Towel Mountains

53. Take a play dough core sample

Learn about the layers of the earth by building them out of Play-Doh, then take a core sample with a straw. ( Love Play-Doh? Get more learning ideas here. )

Learn more: Play Dough Core Sampling

54. Project the stars on your ceiling

Use the video lesson in the link below to learn why stars are only visible at night. Then create a DIY star projector to explore the concept hands-on.

Learn more: DIY Star Projector

55. Make it rain

Use shaving cream and food coloring to simulate clouds and rain. This is an easy science experiment little ones will beg to do over and over.

Learn more: Shaving Cream Rain

56. Blow up your fingerprint

This is such a cool (and easy!) way to look at fingerprint patterns. Inflate a balloon a bit, use some ink to put a fingerprint on it, then blow it up big to see your fingerprint in detail.

57. Snack on a DNA model

Twizzlers, gumdrops, and a few toothpicks are all you need to make this super-fun (and yummy!) DNA model.

Learn more: Edible DNA Model

58. Dissect a flower

Take a nature walk and find a flower or two. Then bring them home and take them apart to discover all the different parts of flowers.

59. Craft smartphone speakers

No Bluetooth speaker? No problem! Put together your own from paper cups and toilet paper tubes.

Learn more: Smartphone Speakers

60. Race a balloon-powered car

Kids will be amazed when they learn they can put together this awesome racer using cardboard and bottle-cap wheels. The balloon-powered “engine” is so much fun too.

Learn more: Balloon-Powered Car

61. Build a Ferris wheel

You’ve probably ridden on a Ferris wheel, but can you build one? Stock up on wood craft sticks and find out! Play around with different designs to see which one works best.

Learn more: Craft Stick Ferris Wheel

62. Design a phone stand

There are lots of ways to craft a DIY phone stand, which makes this a perfect creative-thinking STEM challenge.

63. Conduct an egg drop

Put all their engineering skills to the test with an egg drop! Challenge kids to build a container from stuff they find around the house that will protect an egg from a long fall (this is especially fun to do from upper-story windows).

Learn more: Egg Drop Challenge Ideas

64. Engineer a drinking-straw roller coaster

STEM challenges are always a hit with kids. We love this one, which only requires basic supplies like drinking straws.

Learn more: Straw Roller Coaster

65. Build a solar oven

Explore the power of the sun when you build your own solar ovens and use them to cook some yummy treats. This experiment takes a little more time and effort, but the results are always impressive. The link below has complete instructions.

Learn more: Solar Oven

66. Build a Da Vinci bridge

There are plenty of bridge-building experiments out there, but this one is unique. It’s inspired by Leonardo da Vinci’s 500-year-old self-supporting wooden bridge. Learn how to build it at the link, and expand your learning by exploring more about Da Vinci himself.

Learn more: Da Vinci Bridge

67. Step through an index card

This is one easy science experiment that never fails to astonish. With carefully placed scissor cuts on an index card, you can make a loop large enough to fit a (small) human body through! Kids will be wowed as they learn about surface area.

68. Stand on a pile of paper cups

Combine physics and engineering and challenge kids to create a paper cup structure that can support their weight. This is a cool project for aspiring architects.

Learn more: Paper Cup Stack

69. Test out parachutes

Gather a variety of materials (try tissues, handkerchiefs, plastic bags, etc.) and see which ones make the best parachutes. You can also find out how they’re affected by windy days or find out which ones work in the rain.

Learn more: Parachute Drop

70. Recycle newspapers into an engineering challenge

It’s amazing how a stack of newspapers can spark such creative engineering. Challenge kids to build a tower, support a book, or even build a chair using only newspaper and tape!

Learn more: Newspaper STEM Challenge

71. Use rubber bands to sound out acoustics

Explore the ways that sound waves are affected by what’s around them using a simple rubber band “guitar.” (Kids absolutely love playing with these!)

Learn more: Rubber Band Guitar

72. Assemble a better umbrella

Challenge students to engineer the best possible umbrella from various household supplies. Encourage them to plan, draw blueprints, and test their creations using the scientific method.

Learn more: Umbrella STEM Challenge

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The Flaws and Human Harms of Animal Experimentation

Nonhuman animal (“animal”) experimentation is typically defended by arguments that it is reliable, that animals provide sufficiently good models of human biology and diseases to yield relevant information, and that, consequently, its use provides major human health benefits. I demonstrate that a growing body of scientific literature critically assessing the validity of animal experimentation generally (and animal modeling specifically) raises important concerns about its reliability and predictive value for human outcomes and for understanding human physiology. The unreliability of animal experimentation across a wide range of areas undermines scientific arguments in favor of the practice. Additionally, I show how animal experimentation often significantly harms humans through misleading safety studies, potential abandonment of effective therapeutics, and direction of resources away from more effective testing methods. The resulting evidence suggests that the collective harms and costs to humans from animal experimentation outweigh potential benefits and that resources would be better invested in developing human-based testing methods.

Introduction

Annually, more than 115 million animals are used worldwide in experimentation or to supply the biomedical industry. 1 Nonhuman animal (hereafter “animal”) experimentation falls under two categories: basic (i.e., investigation of basic biology and human disease) and applied (i.e., drug research and development and toxicity and safety testing). Regardless of its categorization, animal experimentation is intended to inform human biology and health sciences and to promote the safety and efficacy of potential treatments. Despite its use of immense resources, the animal suffering involved, and its impact on human health, the question of animal experimentation’s efficacy has been subjected to little systematic scrutiny. 2

Although it is widely accepted that medicine should be evidence based , animal experimentation as a means of informing human health has generally not been held, in practice, to this standard. This fact makes it surprising that animal experimentation is typically viewed as the default and gold standard of preclinical testing and is generally supported without critical examination of its validity. A survey published in 2008 of anecdotal cases and statements given in support of animal experimentation demonstrates how it has not and could not be validated as a necessary step in biomedical research, and the survey casts doubt on its predictive value. 3 I show that animal experimentation is poorly predictive of human outcomes, 4 that it is unreliable across a wide category of disease areas, 5 and that existing literature demonstrates the unreliability of animal experimentation, thereby undermining scientific arguments in its favor. I further show that the collective harms that result from an unreliable practice tip the ethical scale of harms and benefits against continuation in much, if not all, of experimentation involving animals. 6

Problems of Successful Translation to Humans of Data from Animal Experimentation

Although the unreliability and limitations of animal experimentation have increasingly been acknowledged, there remains a general confidence within much of the biomedical community that they can be overcome. 7 However, three major conditions undermine this confidence and explain why animal experimentation, regardless of the disease category studied, fails to reliably inform human health: (1) the effects of the laboratory environment and other variables on study outcomes, (2) disparities between animal models of disease and human diseases, and (3) species differences in physiology and genetics. I argue for the critical importance of each of these conditions.

The Influence of Laboratory Procedures and Environments on Experimental Results

Laboratory procedures and conditions exert influences on animals’ physiology and behaviors that are difficult to control and that can ultimately impact research outcomes. Animals in laboratories are involuntarily placed in artificial environments, usually in windowless rooms, for the duration of their lives. Captivity and the common features of biomedical laboratories—such as artificial lighting, human-produced noises, and restricted housing environments—can prevent species-typical behaviors, causing distress and abnormal behaviors among animals. 8 Among the types of laboratory-generated distress is the phenomenon of contagious anxiety. 9 Cortisone levels rise in monkeys watching other monkeys being restrained for blood collection. 10 Blood pressure and heart rates elevate in rats watching other rats being decapitated. 11 Routine laboratory procedures, such as catching an animal and removing him or her from the cage, in addition to the experimental procedures, cause significant and prolonged elevations in animals’ stress markers. 12 These stress-related changes in physiological parameters caused by the laboratory procedures and environments can have significant effects on test results. 13 Stressed rats, for example, develop chronic inflammatory conditions and intestinal leakage, which add variables that can confound data. 14

A variety of conditions in the laboratory cause changes in neurochemistry, genetic expression, and nerve regeneration. 15 In one study, for example, mice were genetically altered to develop aortic defects. Yet, when the mice were housed in larger cages, those defects almost completely disappeared. 16 Providing further examples, typical noise levels in laboratories can damage blood vessels in animals, and even the type of flooring on which animals are tested in spinal cord injury experiments can affect whether a drug shows a benefit. 17

In order to control for potential confounders, some investigators have called for standardization of laboratory settings and procedures. 18 One notable effort was made by Crabbe et al. in their investigation of the potential confounding influences of the laboratory environment on six mouse behaviors that are commonly studied in neurobehavioral experiments. Despite their “extraordinary lengths to equate test apparatus, testing protocols, and all possible features of animal husbandry” across three laboratories, there were systematic differences in test results in these labs. 19 Additionally, different mouse strains varied markedly in all behavioral tests, and for some tests the magnitude of genetic differences depended on the specific testing laboratory. The results suggest that there are important influences of environmental conditions and procedures specific to individual laboratories that can be difficult—perhaps even impossible—to eliminate. These influences can confound research results and impede extrapolation to humans.

The Discordance between Human Diseases and Animal Models of Diseases

The lack of sufficient congruence between animal models and human diseases is another significant obstacle to translational reliability. Human diseases are typically artificially induced in animals, but the enormous difficulty of reproducing anything approaching the complexity of human diseases in animal models limits their usefulness. 20 Even if the design and conduct of an animal experiment are sound and standardized, the translation of its results to the clinic may fail because of disparities between the animal experimental model and the human condition. 21

Stroke research presents one salient example of the difficulties in modeling human diseases in animals. Stroke is relatively well understood in its underlying pathology. Yet accurately modeling the disease in animals has proven to be an exercise in futility. To address the inability to replicate human stroke in animals, many assert the need to use more standardized animal study design protocols. This includes the use of animals who represent both genders and wide age ranges, who have comorbidities and preexisting conditions that occur naturally in humans, and who are consequently given medications that are indicated for human patients. 22 In fact, a set of guidelines, named STAIR, was implemented by a stroke roundtable in 1999 (and updated in 2009) to standardize protocols, limit the discrepancies, and improve the applicability of animal stroke experiments to humans. 23 One of the most promising stroke treatments later to emerge was NXY-059, which proved effective in animal experiments. However, the drug failed in clinical trials, despite the fact that the set of animal experiments on this drug was considered the poster child for the new experimental standards. 24 Despite such vigorous efforts, the development of STAIR and other criteria has yet to make a recognizable impact in clinical translation. 25

Under closer scrutiny, it is not difficult to surmise why animal stroke experiments fail to successfully translate to humans even with new guidelines. Standard stroke medications will likely affect different species differently. There is little evidence to suggest that a female rat, dog, or monkey sufficiently reproduces the physiology of a human female. Perhaps most importantly, reproducing the preexisting conditions of stroke in animals proves just as difficult as reproducing stroke pathology and outcomes. For example, most animals don’t naturally develop significant atherosclerosis, a leading contributor to ischemic stroke. In order to reproduce the effects of atherosclerosis in animals, researchers clamp their blood vessels or artificially insert blood clots. These interventions, however, do not replicate the elaborate pathology of atherosclerosis and its underlying causes. Reproducing human diseases in animals requires reproducing the predisposing diseases, also a formidable challenge. The inability to reproduce the disease in animals so that it is congruent in relevant respects with human stroke has contributed to a high failure rate in drug development. More than 114 potential therapies initially tested in animals failed in human trials. 26

Further examples of repeated failures based on animal models include drug development in cancer, amyotrophic lateral sclerosis (ALS), traumatic brain injury (TBI), Alzheimer’s disease (AD), and inflammatory conditions. Animal cancer models in which tumors are artificially induced have been the basic translational model used to study key physiological and biochemical properties in cancer onset and propagation and to evaluate novel treatments. Nevertheless, significant limitations exist in the models’ ability to faithfully mirror the complex process of human carcinogenesis. 27 These limitations are evidenced by the high (among the highest of any disease category) clinical failure rate of cancer drugs. 28 Analyses of common mice ALS models demonstrate significant differences from human ALS. 29 The inability of animal ALS models to predict beneficial effects in humans with ALS is recognized. 30 More than twenty drugs have failed in clinical trials, and the only U.S. Food and Drug Administration (FDA)–approved drug to treat ALS is Riluzole, which shows notably marginal benefit on patient survival. 31 Animal models have also been unable to reproduce the complexities of human TBI. 32 In 2010, Maas et al. reported on 27 large Phase 3 clinical trials and 6 unpublished trials in TBI that all failed to show human benefit after showing benefit in animals. 33 Additionally, even after success in animals, around 172 and 150 drug development failures have been identified in the treatment of human AD 34 and inflammatory diseases, 35 respectively.

The high clinical failure rate in drug development across all disease categories is based, at least in part, on the inability to adequately model human diseases in animals and the poor predictability of animal models. 36 A notable systematic review, published in 2007, compared animal experimentation results with clinical trial findings across interventions aimed at the treatment of head injury, respiratory distress syndrome, osteoporosis, stroke, and hemorrhage. 37 The study found that the human and animal results were in accordance only half of the time. In other words, the animal experiments were no more likely than a flip of the coin to predict whether those interventions would benefit humans.

In 2004, the FDA estimated that 92 percent of drugs that pass preclinical tests, including “pivotal” animal tests, fail to proceed to the market. 38 More recent analysis suggests that, despite efforts to improve the predictability of animal testing, the failure rate has actually increased and is now closer to 96 percent. 39 The main causes of failure are lack of effectiveness and safety problems that were not predicted by animal tests. 40

Usually, when an animal model is found wanting, various reasons are proffered to explain what went wrong—poor methodology, publication bias, lack of preexisting disease and medications, wrong gender or age, and so on. These factors certainly require consideration, and recognition of each potential difference between the animal model and the human disease motivates renewed efforts to eliminate these differences. As a result, scientific progress is sometimes made by such efforts. However, the high failure rate in drug testing and development, despite attempts to improve animal testing, suggests that these efforts remain insufficient to overcome the obstacles to successful translation that are inherent to the use of animals. Too often ignored is the well-substantiated idea that these models are, for reasons summarized here, intrinsically lacking in relevance to, and thus highly unlikely to yield useful information about, human diseases. 41

Interspecies Differences in Physiology and Genetics

Ultimately, even if considerable congruence were shown between an animal model and its corresponding human disease, interspecies differences in physiology, behavior, pharmacokinetics, and genetics would significantly limit the reliability of animal studies, even after a substantial investment to improve such studies. In spinal cord injury, for example, drug testing results vary according to which species and even which strain within a species is used, because of numerous interspecies and interstrain differences in neurophysiology, anatomy, and behavior. 42 The micropathology of spinal cord injury, injury repair mechanisms, and recovery from injury varies greatly among different strains of rats and mice. A systematic review found that even among the most standardized and methodologically superior animal experiments, testing results assessing the effectiveness of methylprednisolone for spinal cord injury treatment varied considerably among species. 43 This suggests that factors inherent to the use of animals account for some of the major differences in results.

Even rats from the same strain but purchased from different suppliers produce different test results. 44 In one study, responses to 12 different behavioral measures of pain sensitivity, which are important markers of spinal cord injury, varied among 11 strains of mice, with no clear-cut patterns that allowed prediction of how each strain would respond. 45 These differences influenced how the animals responded to the injury and to experimental therapies. A drug might be shown to help one strain of mice recover but not another. Despite decades of using animal models, not a single neuroprotective agent that ameliorated spinal cord injury in animal tests has proven efficacious in clinical trials to date. 46

Further exemplifying the importance of physiological differences among species, a 2013 study reported that the mouse models used extensively to study human inflammatory diseases (in sepsis, burns, infection, and trauma) have been misleading. The study found that mice differ greatly from humans in their responses to inflammatory conditions. Mice differed from humans in what genes were turned on and off and in the timing and duration of gene expression. The mouse models even differed from one another in their responses. The investigators concluded that “our study supports higher priority to focus on the more complex human conditions rather than relying on mouse models to study human inflammatory disease.” 47 The different genetic responses between mice and humans are likely responsible, at least in part, for the high drug failure rate. The authors stated that every one of almost 150 clinical trials that tested candidate agents’ ability to block inflammatory responses in critically ill patients failed.

Wide differences have also become apparent in the regulation of the same genes, a point that is readily seen when observing differences between human and mouse livers. 48 Consistent phenotypes (observable physical or biochemical characteristics) are rarely obtained by modification of the same gene, even among different strains of mice. 49 Gene regulation can substantially differ among species and may be as important as the presence or absence of a specific gene. Despite the high degree of genome conservation, there are critical differences in the order and function of genes among species. To use an analogy: as pianos have the same keys, humans and other animals share (largely) the same genes. Where we mostly differ is in the way the genes or keys are expressed. For example, if we play the keys in a certain order, we hear Chopin; in a different order, we hear Ray Charles; and in yet a different order, it’s Jerry Lee Lewis. In other words, the same keys or genes are expressed, but their different orders result in markedly different outcomes.

Recognizing the inherent genetic differences among species as a barrier to translation, researches have expressed considerable enthusiasm for genetically modified (GM) animals, including transgenic mice models, wherein human genes are inserted into the mouse genome. However, if a human gene is expressed in mice, it will likely function differently from the way it functions in humans, being affected by physiological mechanisms that are unique in mice. For example, a crucial protein that controls blood sugar in humans is missing in mice. 50 When the human gene that makes this protein was expressed in genetically altered mice, it had the opposite effect from that in humans: it caused loss of blood sugar control in mice. Use of GM mice has failed to successfully model human diseases and to translate into clinical benefit across many disease categories. 51 Perhaps the primary reason why GM animals are unlikely to be much more successful than other animal models in translational medicine is the fact that the “humanized” or altered genes are still in nonhuman animals.

In many instances, nonhuman primates (NHPs) are used instead of mice or other animals, with the expectation that NHPs will better mimic human results. However, there have been sufficient failures in translation to undermine this optimism. For example, NHP models have failed to reproduce key features of Parkinson’s disease, both in function and in pathology. 52 Several therapies that appeared promising in both NHPs and rat models of Parkinson’s disease showed disappointing results in humans. 53 The campaign to prescribe hormone replacement therapy (HRT) in millions of women to prevent cardiovascular disease was based in large part on experiments on NHPs. HRT is now known to increase the risk of these diseases in women. 54

HIV/AIDS vaccine research using NHPs represents one of the most notable failures in animal experimentation translation. Immense resources and decades of time have been devoted to creating NHP (including chimpanzee) models of HIV. Yet all of about 90 HIV vaccines that succeeded in animals failed in humans. 55 After HIV vaccine gp120 failed in clinical trials, despite positive outcomes in chimpanzees, a BMJ article commented that important differences between NHPs and humans with HIV misled researchers, taking them down unproductive experimental paths. 56 Gp120 failed to neutralize HIV grown and tested in cell culture. However, because the serum protected chimpanzees from HIV infection, two Phase 3 clinical trials were undertaken 57 —a clear example of how expectations that NHP data are more predictive than data from other (in this case, cell culture) testing methods are unproductive and harmful. Despite the repeated failures, NHPs (though not chimpanzees or other great apes) remain widely used for HIV research.

The implicit assumption that NHP (and indeed any animal) data are reliable has also led to significant and unjustifiable human suffering. For example, clinical trial volunteers for gp120 were placed at unnecessary risk of harm because of unfounded confidence in NHP experiments. Two landmark studies involving thousands of menopausal women being treated with HRT were terminated early because of increased stroke and breast cancer risk. 58 In 2003, Elan Pharmaceuticals was forced to prematurely terminate a Phase 2 clinical trial when an investigational AD vaccine was found to cause brain swelling in human subjects. No significant adverse effects were detected in GM mice or NHPs. 59

In another example of human suffering resulting from animal experimentation, six human volunteers were injected with an immunomodulatory drug, TGN 1412, in 2006. 60 Within minutes of receiving the experimental drug, all volunteers suffered a severe adverse reaction resulting from a life-threatening cytokine storm that led to catastrophic systemic organ failure. The compound was designed to dampen the immune system, but it had the opposite effect in humans. Prior to this first human trial, TGN 1412 was tested in mice, rabbits, rats, and NHPs with no ill effects. NHPs also underwent repeat-dose toxicity studies and were given 500 times the human dose for at least four consecutive weeks. 61 None of the NHPs manifested the ill effects that humans showed almost immediately after receiving minute amounts of the test drug. Cynomolgus and rhesus monkeys were specifically chosen because their CD28 receptors demonstrated similar affinity to TGN 1412 as human CD28 receptors. Based on such data as these, it was confidently concluded that results obtained from these NHPs would most reliably predict drug responses in humans—a conclusion that proved devastatingly wrong.

As exemplified by the study of HIV/AIDS, TGN 1412, and other experiences, 62 experiments with NHPs are not necessarily any more predictive of human responses than experiments with other animals. The repeated failures in translation from studies with NHPs belie arguments favoring use of any nonhuman species to study human physiology and diseases and to test potential treatments. If experimentation using chimpanzees and other NHPs, our closest genetic cousins, are unreliable, how can we expect research using other animals to be reliable? The bottom line is that animal experiments, no matter the species used or the type of disease research undertaken, are highly unreliable—and they have too little predictive value to justify the resultant risks of harms for humans, for reasons I now explain.

The Collective Harms That Result from Misleading Animal Experiments

As medical research has explored the complexities and subtle nuances of biological systems, problems have arisen because the differences among species along these subtler biological dimensions far outweigh the similarities , as a growing body of evidence attests. These profoundly important—and often undetected—differences are likely one of the main reasons human clinical trials fail. 63

“Appreciation of differences” and “caution” about extrapolating results from animals to humans are now almost universally recommended. But, in practice, how does one take into account differences in drug metabolism, genetics, expression of diseases, anatomy, influences of laboratory environments, and species- and strain-specific physiologic mechanisms—and, in view of these differences, discern what is applicable to humans and what is not? If we cannot determine which physiological mechanisms in which species and strains of species are applicable to humans (even setting aside the complicating factors of different caging systems and types of flooring), the usefulness of the experiments must be questioned.

It has been argued that some information obtained from animal experiments is better than no information. 64 This thesis neglects how misleading information can be worse than no information from animal tests. The use of nonpredictive animal experiments can cause human suffering in at least two ways: (1) by producing misleading safety and efficacy data and (2) by causing potential abandonment of useful medical treatments and misdirecting resources away from more effective testing methods.

Humans are harmed because of misleading animal testing results. Imprecise results from animal experiments may result in clinical trials of biologically faulty or even harmful substances, thereby exposing patients to unnecessary risk and wasting scarce research resources. 65 Animal toxicity studies are poor predictors of toxic effects of drugs in humans. 66 As seen in some of the preceding examples (in particular, stroke, HRT, and TGN1412), humans have been significantly harmed because investigators were misled by the safety and efficacy profile of a new drug based on animal experiments. 67 Clinical trial volunteers are thus provided with raised hopes and a false sense of security because of a misguided confidence in efficacy and safety testing using animals.

An equal if indirect source of human suffering is the opportunity cost of abandoning promising drugs because of misleading animal tests. 68 As candidate drugs generally proceed down the development pipeline and to human testing based largely on successful results in animals 69 (i.e., positive efficacy and negative adverse effects), drugs are sometimes not further developed due to unsuccessful results in animals (i.e., negative efficacy and/or positive adverse effects). Because much pharmaceutical company preclinical data are proprietary and thus publicly unavailable, it is difficult to know the number of missed opportunities due to misleading animal experiments. However, of every 5,000–10,000 potential drugs investigated, only about 5 proceed to Phase 1 clinical trials. 70 Potential therapeutics may be abandoned because of results in animal tests that do not apply to humans. 71 Treatments that fail to work or show some adverse effect in animals because of species-specific influences may be abandoned in preclinical testing even if they may have proved effective and safe in humans if allowed to continue through the drug development pipeline.

An editorial in Nature Reviews Drug Discovery describes cases involving two drugs in which animal test results from species-specific influences could have derailed their development. In particular, it describes how tamoxifen, one of the most effective drugs for certain types of breast cancer, “would most certainly have been withdrawn from the pipeline” if its propensity to cause liver tumor in rats had been discovered in preclinical testing rather than after the drug had been on the market for years. 72 Gleevec provides another example of effective drugs that could have been abandoned based on misleading animal tests: this drug, which is used to treat chronic myelogenous leukemia (CML), showed serious adverse effects in at least five species tested, including severe liver damage in dogs. However, liver toxicity was not detected in human cell assays, and clinical trials proceeded, which confirmed the absence of significant liver toxicity in humans. 73 Fortunately for CML patients, Gleevec is a success story of predictive human-based testing. Many useful drugs that have safely been used by humans for decades, such as aspirin and penicillin, may not have been available today if the current animal testing regulatory requirements were in practice during their development. 74

A further example of near-missed opportunities is provided by experiments on animals that delayed the acceptance of cyclosporine, a drug widely and successfully used to treat autoimmune disorders and prevent organ transplant rejection. 75 Its immunosuppressive effects differed so markedly among species that researchers judged that the animal results limited any direct inferences that could be made to humans. Providing further examples, PharmaInformatic released a report describing how several blockbuster drugs, including aripiprazole (Abilify) and esomeprazole (Nexium), showed low oral bioavailability in animals. They would likely not be available on the market today if animal tests were solely relied on. Understanding the implications of its findings for drug development in general, PharmaInformatic asked, “Which other blockbuster drugs would be on the market today, if animal trials would have not been used to preselect compounds and drug-candidates for further development?” 76 These near-missed opportunities and the overall 96 percent failure rate in clinical drug testing strongly suggest the unsoundness of animal testing as a precondition of human clinical trials and provide powerful evidence for the need for a new, human-based paradigm in medical research and drug development.

In addition to potentially causing abandonment of useful treatments, use of an invalid animal disease model can lead researchers and the industry in the wrong research direction, wasting time and significant investment. 77 Repeatedly, researchers have been lured down the wrong line of investigation because of information gleaned from animal experiments that later proved to be inaccurate, irrelevant, or discordant with human biology. Some claim that we do not know which benefits animal experiments, particularly in basic research, may provide down the road. Yet human lives remain in the balance, waiting for effective therapies. Funding must be strategically invested in the research areas that offer the most promise.

The opportunity costs of continuing to fund unreliable animal tests may impede development of more accurate testing methods. Human organs grown in the lab, human organs on a chip, cognitive computing technologies, 3D printing of human living tissues, and the Human Toxome Project are examples of new human-based technologies that are garnering widespread enthusiasm. The benefit of using these testing methods in the preclinical setting over animal experiments is that they are based on human biology. Thus their use eliminates much of the guesswork required when attempting to extrapolate physiological data from other species to humans. Additionally, these tests offer whole-systems biology, in contrast to traditional in vitro techniques. Although they are gaining momentum, these human-based tests are still in their relative infancy, and funding must be prioritized for their further development. The recent advancements made in the development of more predictive, human-based systems and biological approaches in chemical toxicological testing are an example of how newer and improved tests have been developed because of a shift in prioritization. 78 Apart from toxicology, though, financial investment in the development of human-based technologies generally falls far short of investment in animal experimentation. 79

The unreliability of applying animal experimental results to human biology and diseases is increasingly recognized. Animals are in many respects biologically and psychologically similar to humans, perhaps most notably in the shared characteristics of pain, fear, and suffering. 80 In contrast, evidence demonstrates that critically important physiological and genetic differences between humans and other animals can invalidate the use of animals to study human diseases, treatments, pharmaceuticals, and the like. In significant measure, animal models specifically, and animal experimentation generally, are inadequate bases for predicting clinical outcomes in human beings in the great bulk of biomedical science. As a result, humans can be subject to significant and avoidable harm.

The data showing the unreliability of animal experimentation and the resultant harms to humans (and nonhumans) undermine long-standing claims that animal experimentation is necessary to enhance human health and therefore ethically justified. Rather, they demonstrate that animal experimentation poses significant costs and harms to human beings. It is possible—as I have argued elsewhere—that animal research is more costly and harmful, on the whole, than it is beneficial to human health. 81 When considering the ethical justifiability of animal experiments, we should ask if it is ethically acceptable to deprive humans of resources, opportunity, hope, and even their lives by seeking answers in what may be the wrong place. In my view, it would be better to direct resources away from animal experimentation and into developing more accurate, human-based technologies.

Aysha Akhtar , M.D., M.P.H., is a neurologist and preventive medicine specialist and Fellow at the Oxford Centre for Animal Ethics, Oxford, United Kingdom.

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Science and History of GMOs and Other Food Modification Processes

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How has genetic engineering changed plant and animal breeding?

Did you know.

Genetic engineering is often used in combination with traditional breeding to produce the genetically engineered plant varieties on the market today.

For thousands of years, humans have been using traditional modification methods like selective breeding and cross-breeding to breed plants and animals with more desirable traits. For example, early farmers developed cross-breeding methods to grow corn with a range of colors, sizes, and uses. Today’s strawberries are a cross between a strawberry species native to North America and a strawberry species native to South America.

Most of the foods we eat today were created through traditional breeding methods. But changing plants and animals through traditional breeding can take a long time, and it is difficult to make very specific changes. After scientists developed genetic engineering in the 1970s, they were able to make similar changes in a more specific way and in a shorter amount of time.

A Timeline of Genetic Modification in Agriculture

A Timeline of Genetic Modification in Modern Agriculture

Circa 8000 BCE: Humans use traditional modification methods like selective breeding and cross-breeding to breed plants and animals with more desirable traits.

1866: Gregor Mendel, an Austrian monk, breeds two different types of peas and identifies the basic process of genetics.

1922: The first hybrid corn is produced and sold commercially.

1940: Plant breeders learn to use radiation or chemicals to randomly change an organism’s DNA.

1953: Building on the discoveries of chemist Rosalind Franklin, scientists James Watson and Francis Crick identify the structure of DNA.

1973: Biochemists Herbert Boyer and Stanley Cohen develop genetic engineering by inserting DNA from one bacteria into another.

1982: FDA approves the first consumer GMO product developed through genetic engineering: human insulin to treat diabetes.

1986: The federal government establishes the Coordinated Framework for the Regulation of Biotechnology. This policy describes how the U.S. Food and Drug Administration (FDA), U.S. Environmental Protection Agency (EPA), and U.S. Department of Agriculture (USDA) work together to regulate the safety of GMOs.

1992: FDA policy states that foods from GMO plants must meet the same requirements, including the same safety standards, as foods derived from traditionally bred plants.

1994: The first GMO produce created through genetic engineering—a GMO tomato—becomes available for sale after studies evaluated by federal agencies proved it to be as safe as traditionally bred tomatoes.

1990s: The first wave of GMO produce created through genetic engineering becomes available to consumers: summer squash, soybeans, cotton, corn, papayas, tomatoes, potatoes, and canola. Not all are still available for sale.

2003: The World Health Organization (WHO) and the Food and Agriculture Organization (FAO) of the United Nations develop international guidelines and standards to determine the safety of GMO foods.

2005: GMO alfalfa and sugar beets are available for sale in the United States.

2015: FDA approves an application for the first genetic modification in an animal for use as food, a genetically engineered salmon.

2016: Congress passes a law requiring labeling for some foods produced through genetic engineering and uses the term “bioengineered,” which will start to appear on some foods.

2017: GMO apples are available for sale in the U.S.

2019: FDA completes consultation on first food from a genome edited plant.

2020 : GMO pink pineapple is available to U.S. consumers.

2020 : Application for GalSafe pig was approved.

How are GMOs made?

“GMO” (genetically modified organism) has become the common term consumers and popular media use to describe foods that have been created through genetic engineering. Genetic engineering is a process that involves:

• Identifying the genetic information—or “gene”—that gives an organism (plant, animal, or microorganism) a desired trait
• Copying that information from the organism that has the trait
• Inserting that information into the DNA of another organism
• Then growing the new organism

How Are GMOs Made? Fact Sheet

Making a GMO Plant, Step by Step

The following example gives a general idea of the steps it takes to create a GMO plant. This example uses a type of insect-resistant corn called “Bt corn.” Keep in mind that the processes for creating a GMO plant, animal, or microorganism may be different.

To produce a GMO plant, scientists first identify what trait they want that plant to have, such as resistance to drought, herbicides, or insects. Then, they find an organism (plant, animal, or microorganism) that already has that trait within its genes. In this example, scientists wanted to create insect-resistant corn to reduce the need to spray pesticides. They identified a gene in a soil bacterium called Bacillus thuringiensis (Bt) , which produces a natural insecticide that has been in use for many years in traditional and organic agriculture.

After scientists find the gene with the desired trait, they copy that gene.

For Bt corn, they copied the gene in Bt that would provide the insect-resistance trait.

Next, scientists use tools to insert the gene into the DNA of the plant. By inserting the Bt gene into the DNA of the corn plant, scientists gave it the insect resistance trait.

This new trait does not change the other existing traits.

In the laboratory, scientists grow the new corn plant to ensure it has adopted the desired trait (insect resistance). If successful, scientists first grow and monitor the new corn plant (now called Bt corn because it contains a gene from Bacillus thuringiensis) in greenhouses and then in small field tests before moving it into larger field tests. GMO plants go through in-depth review and tests before they are ready to be sold to farmers.

The entire process of bringing a GMO plant to the marketplace takes several years.

Learn more about the process for creating genetically engineered microbes and genetically engineered animals .

What are the latest scientific advances in plant and animal breeding?

Scientists are developing new ways to create new varieties of crops and animals using a process called genome editing . These techniques can make changes more quickly and precisely than traditional breeding methods.

There are several genome editing tools, such as CRISPR . Scientists can use these newer genome editing tools to make crops more nutritious, drought tolerant, and resistant to insect pests and diseases.

Learn more about Genome Editing in Agricultural Biotechnology .

How GMOs Are Regulated in the United States

GMO Crops, Animal Food, and Beyond

How GMO Crops Impact Our World

www.fda.gov/feedyourmind

Unpacking the story of Fauci and painful experiments involving dogs

Documents obtained by an animal rights group show that NIH was not fully transparent when the controversy erupted in 2021.

PETA supporter ran onto field before Red Sox game to protest UMass

• Published: Jun. 03, 2024, 12:42 p.m.

A man protesting experiments conducted on marmosets at UMass ran onto Fenway Park Friday as University of Massachusetts–Amherst Chancellor Javier Reyes was throwing out the first pitch. PETA

• Heather Morrison | [email protected]

A man protesting experiments conducted on marmosets at UMass ran onto Fenway Park Friday as University of Massachusetts–Amherst Chancellor Javier Reyes was throwing out the first pitch.

The man supports the People for the Ethical Treatment of Animals (PETA) and wore a black T-shirt with writing on it asking UMass to end its testing on the monkeys. He also had a sign that read: “Chancellor Reyes: End Cruel Tests on Marmosets!”

The protester was escorted out by security, according to PETA.

• Read more: After bear euthanized in Hatfield, PETA says animals need ‘wide berth’

PETA and UMass have had a years-long struggle over the use of animal subjects in university research. PETA has said that UMass researchers perform experiments that mistreat animals and house creatures, including marmoset monkeys and hamsters, in cramped and inhumane conditions. The university maintains that the animal welfare organization’s assertions misrepresent its laboratories and research.

UMass claims the research aims to better understand Alzheimer’s disease and women’s health by studying the marmosets.

The monkeys’ short lifespans — about a decade — and cognitive decline with age allow researchers to track brain function over a manageable timeline, compared to the decades it would take to study a human across their whole life.

UMass’ experiments gauge cognitive functions in the marmosets by asking them to identify shapes and odors and solve tests using fine motor skills. The researchers also track the monkeys’ sleep, according to an informational webpage organized by lead UMass researcher Dr. Agnès Lacreuse.

• Read more: PETA again puts spotlight on monkey research at UMass Amherst

PETA has levied an assortment of accusations against UMass concerning the research — that experimenters “drill into [marmosets’] skulls and implant electrodes,” that they “cut out [monkeys] ovaries and heat the animals with hand warmers” and that they keep monkeys in solitary confinement.

“While Chancellor Reyes frolics at Fenway, tiny monkeys are being tormented at the university in cruel and scientifically worthless experiments,” PETA Senior Vice President Kathy Guillermo said on Friday. “PETA calls on Chancellor Reyes to shut down this disgraceful laboratory and urges the school to switch to modern, animal-free research methods that might actually benefit women.”

UMass and Lacreuse dispute each of these complaints.

The researchers implant a “small telemeter” on the monkeys’ heads, just under the skin, to record brain activity, Lacreuse said. The surgery is conducted by a licensed veterinarian, she said, and allows researchers to track monkeys’ sleep without disturbing them.

Lacreuse’s website acknowledged neutering and spaying the animals, which for female marmosets involves removing their ovaries. The process is the same as with a house cat or pet dog, Lacreuse said, and the animals are given appropriate anesthetics and medications during the surgery conducted by a veterinarian.

The monkeys are also heated with hand warmers to simulate the symptoms of menopause, a process they do not go through naturally. While PETA has questioned the necessity and humanity of the experiment, Lacreuse said that understanding marmosets’ ability to regulate their body temperature could prove key to understanding the symptoms of menopause, including hot flashes.

• Read more: Springfield officials defend fire chief running over suspected rabid raccoon with SUV

Part of the research involves studying women’s health in order to understand why two-thirds of Alzheimer’s cases are in women, Lacreuse said.

In 2021, PETA members protested at the center of the UMass Amherst campus alongside Massachusetts-born actor Casey Affleck, a longtime supporter of the organization.

“You don’t have to be a scientist to know right from wrong,” Affleck said in 2021. “The bottom line is the animals used here in these unnecessary and cruel experiments suffer. That should be enough to tell us that we have to find another way to do this research.”

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Want to See Bison at Yellowstone? You’re Likely Not Prepared.

An 83-year-old woman was gored Saturday by a bison. Experts offered advice on how to avoid a similar situation.

By Derrick Bryson Taylor

In the deep green pastures of Yellowstone National Park, where the air is crisp and the tall grass dances in the breeze, lives the bison, a large, majestic animal with chocolate brown fur — and a delicate temperament that could turn from pleasant to dangerous in seconds.

Bison have injured more people in Yellowstone than any other animal, a national park official said. On average, there are one to two reported incidents of bison injuring visitors annually. However, bison at the park have not killed any people in the last five years.

Last weekend, an 83-year-old woman from South Carolina was gored by a bison that was defending its space, park officials said. She sustained serious injuries after being lifted about a foot off the ground by the animal’s horns. The incident remains under investigation.

It was the latest in a string of tragic events at the park involving visitors and bison, which are social animals that live in herds. In April, a 40-year-old man was injured after harassing a herd of bison and kicking one of the animals in the leg. Last July, a 47-year-old woman sustained significant injuries after being charged and gored by a bison. Just weeks earlier, a man pleaded guilty to one count of feeding, touching, teasing, frightening or intentionally disturbing wildlife after interacting with a newborn bison calf, which had to be euthanized .

Episodes like these occur too regularly, said Jon Grinnell, associate professor of biology and a bison expert at Gustavus Adolphus College in Minnesota. “I think it’s a sign of how unfamiliar people are with dealing with wild animals,” he said. “They think they are tame things that will respect them, and they won’t always do that.”

Still, visiting Yellowstone to learn about the animals could be beneficial, Mr. Grinnell said. “If the only exposure to wildlife is through the internet, that’s going to teach them some dangerous behaviors,” he said. “It’s much better to respect the animals and give it space and not have to have that selfie taken with the bison bull.”

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