Killing animals and humans

Scientists and researchers have devised endless ways of abusing animals in experiments. They use them to test weedkillers and pesticides as well as new ingredients for cleaning fluids, paints, food, drinks and even pet food.

Animals are also used in medical research, in an attempt to find the causes of, and treatments for, human disease. But animal experiments are unreliable and can be dangerously misleading because animals’ bodies are different from ours, and they don’t get the same diseases as we do.

Thousands of chimpanzees have been used in useless experiments to find a cure for AIDS, but it is now known that, whilst it kills humans, AIDS won’t kill chimpanzees. The link between smoking and lung cancer was first observed in people but because no animals developed cancer when forced to inhale tobacco smoke, vital health warnings were delayed by many years. No one knows how many people died as a result of the misleading information provided by animal experiments.

Drugs affect animals differently from us. Drugs such as aspirin and paracetamol, commonly used to treat people, are highly poisonous to cats. Although Alexander Fleming discovered penicillin in 1928, it was not until ten years later that it was tested, first in animals, and then subsequently in humans. Early researchers chose to test penicillin on mice and the encouraging results led to its use in humans. Had they chosen to test it on hamsters or guinea pigs, it is likely that penicillin would have been discarded, as it is lethal to both species.

On the other hand, each year drugs that were passed as safe in animal tests are withdrawn after causing serious side-effects, and even deaths, when given to people. Examples include Vioxx – the animal-tested arthritis drug – which was reported to have caused up to 140,000 heart attacks and strokes before being withdrawn. And the TGN1412 (‘elephant man’ drug) disaster that left six men with organ failure after tests on monkeys failed to predict these effects.

The many differences – both obvious and very subtle – between humans and other species make animal experiments a waste of time, effort, money and lives – both human and animal.

How many animals are used?

In the UK, around four million animals are used in laboratory experiments each year. Hundreds of thousands more animals are bred and killed so bits of their bodies can be used in research. In addition, millions of ‘surplus’ animals are bred but never used – they are just disposed of and their deaths are not even recorded.

Which animals are used?

Mostly mice and rats because they are small, cheap and easy to breed, but guinea pigs, rabbits, cats, dogs, monkeys, birds, reptiles, pigs, sheep, cattle, chickens, horses and fish are also routinely used.

Genetically modified animals

Hundreds of thousands of genetically engineered animals are specially bred every year. The numbers are increasing dramatically as this is now the most rapidly expanding area of animal experimentation. These animals are deliberately manipulated by having specific genes added, removed or damaged to make them grow abnormally, automatically develop a particular disease or be born with certain characteristics the researcher wants to examine. For example, a new type of ‘mini pig’ has been developed for use in the laboratory and genetically modified mice have been created so that they are born with a form of cystic fibrosis or develop cancer. Animals suffer horribly in genetic research because tinkering with animals’ genes can cause severe physical and developmental abnormalities – some of which are planned, while others are unintended.

Mice are by far the most commonly used animal in GM research. And for every GM mouse used in an experiment, hundreds more die or are killed, either because they are surplus to requirements, because they fail to exhibit the desired genetic alteration or because they are born with other, unintended malformations. Many of these mice are not even recognised in official government statistics on animal research.

If they survive the breeding process, many GM mice are then subjected to cruel and invasive experiments. For example, in epilepsy research, seizures are triggered in mice by rapidly and repeatedly tossing them in the air. In depression studies, mice are placed in a beaker of water from which they cannot escape, and monitored as they move from frantic attempts to save themselves from drowning to despair, defeat and immobility.

What happens in laboratories?

The government defines an animal experiment as a ‘procedure’ which is ‘likely to cause… pain, suffering, distress, or lasting harm’.

Laboratory animals are typically kept in small, bare cages or kennels, generally denied any comfort or stimulation. Until they are killed at the end of the experiment – which could last days, weeks, months or even years – their lives are marked by pain and fear. Deprived of the ability to exercise any of their natural instincts and stressed due to the frustration of confinement, the animals are not even being examined in a ‘normal’ condition, which has the potential to skew results from the start.

What laws govern animal experiments?

In the UK, vivisection is controlled by the Animals (Scientific Procedures) Act 1986, which states that experiments can take place only if the expected benefits to humans outweigh the animals’ suffering. In practice, though, it allows experiments for almost any reason, such as testing food additives, weapons, tobacco material and alcohol. And, in reality, no animal experiments help people because the information obtained is unreliable. Scientists like to keep their experiments secret and the Act encourages that – in fact, someone working in a lab can be imprisoned for two years simply for exposing what takes place! In contrast, no animal researcher has ever been prosecuted under the 1986 Act, despite undercover investigations showing, for instance, dogs being punched violently and data being fabricated, brain-damaged monkeys left unmonitored overnight following surgery, and researchers laughing as they smashed live mice against bench tops to kill them.

What kinds of experiments are carried out?

Product ‘safety’ tests:

Animals are damaged and killed to test the safety of new agricultural and industrial chemicals, food additives and household cleaning products. They are force-fed substances, they have chemicals rubbed into their skin or dripped into their eyes and they are made to inhale smoke or toxic fumes to see how poisonous they are. Thankfully, testing cosmetic products and ingredients on animals within the European Union is now banned. Other countries still test cosmetics on animals, but as from March 11th 2013, no new cosmetic products that have ingredients which have been tested on animals have been allowed to be sold within the EU.

Medical research:

New drugs and surgical techniques intended for people are first tested on animals. Animals are surgically damaged, given cancer, infected with viruses, brain damaged and injured in other ways in an attempt to recreate human diseases. In arthritis research, animals are injected in their joints (with collagen or various other substances) to produce the painful swellings and destruction of cartilage and bone that is characteristic of the disease. Animals are also fed addictive substances in order to study dependency.

Warfare research:

Animals are maimed, shot, irradiated, blown up, and dosed and poisoned with chemicals and gases.

Pain analysis:

Levels of pain are measured in barbaric tests such as putting animals on hot plates or dipping their tails in boiling water. Severe pain can be induced by injections of the chemical formalin.

Psychology research:

Animals are deliberately driven mad, starved, given electric shocks, brain damaged, deprived of sleep and taken from their mothers to see how this affects their behaviour.

Stress is produced by dropping animals into tanks of water and forcing them to swim to stay alive. Epileptic fits are induced by electric shocks, flashing lights, loud noises and chemicals. Electrodes surgically planted into their brains allow scientists to measure brain activity while they are abused in these ways.

Who’s paying for these experiments?

In the UK, animal experiments are carried out by contract research organisations (CROs) who conduct research on behalf of other parties, including drug, crop protection or chemical companies,  Shockingly, around half of all procedures are carried out at universities. Many medical research charities, such as Cancer Research UK and the British Heart Foundation, also fund research using animals.

The failure of animal research

Time and time again, animal experiments have failed when their results have been applied to human beings. In fact, studies of the predictability of animal experiments consistently show them to be worse than random guesswork. For example, in one paper (1) that reviewed drugs whose toxicity to humans caused their withdrawal from the market (1960-1990), only 4 out of 24 cases were predictable from animal data. In another review (2) only 6 of 114 human toxicities had animal correlates.

Many drugs, which have been safety-tested in animals go on to cause serious side-effects, including death, in people. In 2006, the British Medical Association announced that at least 250,000 people are hospitalised every year as a result of adverse drug reactions. An earlier survey revealed that the annual death toll could be as high as 10,000. A 2004 study found that damaging side-effects of drugs are responsible for four per cent of hospital bed capacity and cost the NHS £466m a year.

Clearly, animal tests are failing to protect people. According to Hospital Doctor journal, only one per cent of adverse drug reactions are detected in trials. This is partly because common symptoms, such as nausea, dizziness, headaches and visual disturbance, are essentially impossible to detect in animals. Furthermore, the lives of commonly used laboratory animals are up to 66 times shorter than that of a human being – making it difficult to identify side effects that are slow to develop.

Dozens of treatments for stroke have been developed in animals but none has been successful in humans. And according to the US National Cancer Institute, cures for cancer have been lost because of experiments on animals.

James Shapiro, a researcher at the Canadian Institutes of Health, states: ‘A diabetes cure is announced every week in mice, but very few of these strategies ultimately translate to a meaningful cure in the clinic.’

Primate experiments: hurting animals and harming people

Britain is one of the largest user of primates for research in Europe. Because they are, genetically, our closest relatives in the animal kingdom, researchers claim that they make reliable ‘models’ in which to study human disease or product toxicity. But although they are indeed very similar, they are not the same: profound differences at the molecular level and the fact that their brains are many times smaller and function differently from those of human beings makes experimenting on them futile at best, dangerous at worst.

Time and time again, primate research has failed to predict dangerous side effects of medications. It has also led researchers down blind alleys and delayed real cures reaching people.

For example:

  • Hormone replacement therapy – given to millions of women following research in monkeys – has recently been found to increase their risk of heart disease, stroke and breast cancer. (3)
  • The so-called ‘elephant man’ drug, TGN1412, caused six healthy volunteers to suffer multiple organ failure. Earlier tests involving at least 25 monkeys showed TGN1412 to be quite safe.
  • Isoprenaline doses (for asthma) were worked out on animals, but proved too high for humans. Thousands of people died as a result. Even when the researchers knew what to look for they were unable to reproduce this effect in monkeys. (4)
  • Carbenoxalone (a gastric ulcer treatment) caused people to retain water to the point of heart failure. Scientists retrospectively tested it on monkeys, but could not reproduce this effect. (5)
  • Flosint (an arthritis drug) was tested on monkeys – they tolerated the medication well. In humans, however, it caused deaths. (6)
  • Amrinone (for heart failure) was tested on numerous non-human primates and released with confidence. People haemorrhaged, as the drug prevented normal blood clotting. This side effect occurred in a startling 20 per cent of patients taking the medication on a long-term basis. (7)
  • Arthritis drug Opren is known to have killed 61 people. Over 3,500 cases of severe reactions have been documented. Opren was tested on monkeys without problems. (8)
  • Aspirin causes birth defects in monkeys but not in humans. (9)
  • 20 years and vast amounts of resources have been wasted on misleading AIDS research in animals. An important vaccine, Aidsvax – deemed a success in chimpanzees – was pronounced a failure in 2003 having failed to protect the 8,000 high-risk volunteers in the trial.

The way ahead

Stopping animal experiments will not mean an end to medical progress – far from it. But in order to obtain data that is applicable to human health, we need to focus our resources on human-based medicine and research methods. There is a whole range of modern, rapid and accurate tests now on stream:

  • Human Tissues: human cells, tissues and segments of DNA can be processed and assessed through highly sophisticated, rapid screening techniques.
  • Computer modelling: sophisticated computers can imitate the workings of the human body and duplicate the spread of disease so that researchers can predict how drugs will work and what effect they will have.
  • Microdosing: tiny amounts of an experimental drug are tracked in the human body by radioactive labelling.
  • DNA chips: allow thousands of genes to be monitored simultaneously for their response to a substance such as a new drug.
  • Microfluidics chips: contain tissue samples from various different parts of the human body in tiny chambers linked by microchannels, through which a blood substitute flows, to mimic, on a tiny scale, what goes on in the human body.
  • Scans: sophisticated MRI, CAT and PET scanners allow detailed analysis of the brains and other organs of conscious patients without surgery.
  • Epidemiology: the study and comparison of groups of people to analyse health problems.
  • Clinical case studies: monitoring illness in individual patients.
  • Post-mortem studies: examining the bodies of people who have died can give clues about disease.

It is vital that we also focus our attention on education and the prevention of disease and in providing better health care for those already ill. Much progress could be made by promoting healthier eating, more exercise and a crackdown on the polluting activities of industry and intensive farming.

For more information on the scientific argument against animal experiments, go to

Humane research

Nearly half a million animals are bred and killed every year so that their body parts can be used in test tube studies. At the same time, huge amounts of a more logical research material are being incinerated: human tissue. Animal Aid campaigns for the use of human tissue in research as an alternative to animals, not only because it saves animals’ lives, but also because the results obtained are of direct relevance to people.

For additional information, see our report Human Tissue Research


  1. Heywood R, 1990; Clinical toxicity – could it have been predicted? in Animal Toxicity Studies: their relevance for man, (Lumley and Walker, Eds) p57-67
  2. Spriet-Pourra, C and Auriche, M, (Eds) 1994, SCRIP Reports, PJB, New York
  3. H D Nelson et al, Journal of the American Medical Association (2002) 288: 872-881, Cancer (2003) 97: 1442
  4. S Carson et al, Pharmacologist (1971) 18: 272
  5. CT Eason et al, Regulatory Toxicology and Pharmacology (1990) 11:288-307
  6. RD Mann, Modern Drug Use, an Enquiry on Historical Principles, MTP Press 1984
  7. Human Toxicology (1987) 6: 436
  8. CT Eason et al, Regulatory Toxicology and Pharmacology (1990) 11:288-307
  9. Lancet (1962) 599-600