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10 Most Dangerous Scientific Experiments in History

The times in history when science was deadly and dangerous.
A masked ecologist militant is pictured with a barrel falsely contaminated during a demonstration against nuclear energy near the Tricastin nuclear power plant run by Areva in Bollene, southern France, on November 25, 2011, during a visit of France's Pres

Science is a force for good in our world, improving lives of people all across Earth in immeasurable ways. But it is also a very powerful tool that can become dangerous in some situations. Especially when it gets entangled in politics. At other times, science’s inherent ambition to push boundaries of what is known can also lead to some heart-stopping moments. 

The following list is in no way exhaustive but gives us a place to start when thinking about the serious responsibility that comes with the march of science.

1. Project MKUltra 

The infamous project MKUltra was CIA’s attempt at mastering mind control. The program started in the 1950s and lasted seemingly until 1966. Under MKUltra, often-unwilling subjects were given drugs, especially hallucinogenics like LSD. The people tested were also put through sleep and sensory deprivation, hypnosis, sexual abuse, and other kinds of psychological torture, while some tests proved lethal.

The supposed goal of the project was some combination of chemical weapons research and effort to create mind-controlling drugs to combat the Soviets. 

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2. Weaponizing the Plague

The last time plague roamed around, it killed around half of Europe’s population, reducing the amount of people in the world by nearly a 100 million during the 13th and 14th century. In the late 1980s, the Soviet Union’s biological warfare research program figured out how to use the plague as a weapon, to be launched at enemies in missile warheads. What could go wrong? Besides the plague, defectors revealed that the Soviet bio-weapons program also had hundreds of tons of anthrax and tons of smallpox.

3. The Large Hadron Supercollider 

The Large Hadron Collider (LHC) in Switzerland, built to study particle physics, is the world’s largest machine and single most sophisticated scientific instrument. Because of this and the cutting-edge research its involved in, the LHC has prompted more than its share of fears from the general public. It has been blamed for causing earthquakes and pulling asteroids towards Earth.

A giant magnet used in the Large Hadron Collider, weighing 1920 tonnes. 28 February, 2007 at the European Organization for Nuclear Research (CERN) in Geneva. (Photo credit: JEAN-PIERRE CLATOT/AFP/Getty Images)

While conspiracy theories around the LHC have generally been disproven, it has also been accused of potentially creating black holes that could swallow Earth, a possibility that was curiously not completely discounted by the CERN, the organization running the collider. 

CERN claimed the LHC is not dangerous, but also acknowledged that some type of black hole could be created. 

“The LHC will not generate black holes in the cosmological sense. However, some theories suggest that the formation of tiny ‘quantum’ black holes may be possible. The observation of such an event would be thrilling in terms of our understanding of the Universe; and would be perfectly safe,“ said CERN’s statement.

A quantum black hole would be tiny. Don’t you feel better?

4. The Tuskegee Syphilis Experiment

A government-funded “study” from 1932-1972 denied treatment for syphilis to 399 African American patients in rural Alabama, even as penicillin was found to be effective against the disease in 1947. The patients were actually not told they had syphilis, with doctors blaming their “bad blood” instead and given placebos.

The goal of the experiment, carried out by the U.S. Public Health Service, was to study the natural progress of syphilis if left untreated. 28 of the people in the study died directly from syphilis while 100 died from related complications. 

Doctor drawing blood from a patient as part of the Tuskegee Syphilis Study. 1932.

5. Kola Superdeep Borehole

A Soviet experiment, started in 1970, sought to drill as deeply as possible into the crust of the planet. By 1994, they bore a 12-km-deep hole into the Kola Peninsula in Russia’s far northwest. The record dig provided much scientific data, like the finding of ancient microscopic plankton fossils from 24 species.

While nothing negative happened, there were concerns at the time that drilling so deep towards the center of Earth might produce unexpected seismic effects. Like cracking the planet open.

The hole’s site is currently closed. 

6. Guatemalan STD study

This horrid experiment is another instance of the U.S. government causing harm in the pursuit of “science”. From 1945 until 1956, around 1500 Guatemalans were deliberately infected with sexually transmitted diseases, including syphilis and gonorrhoea. The subjects included orphans, prisoners, prostitutes and military conscripts. Researchers used disease-infected prostitutes, injections, and other unscrupulous methods to make their subjects sick. 

Subjects of the experiment are currently suing John Hopkins University for $1 billion for its role in the study.

7. The Aversion Project

A medical torture program was instituted in South Africa between 1971 and 1989 to “cure” homosexuality in military conscripts. The policy, carried out under apartheid, included forced “aversion therapy” treatments like electric shock therapy and chemical castration. The army also authorized as many as 900 sex change operations.

It was widely believed in the medical community at the time that homosexuality was a mental illness that could be cured. Dr. Aubrey Levin, in charge of the program as chief psychiatrist of the South African military, was eventually accused of human rights abuse by international organizations and received a prison sentence. 

8. Nazi Concentration Camp Experiments

Nazis carried out medical experiments on thousands of prisoners in concentration camps, without any regard for human life. Some of their “research” involved purposefully inducing hypothermia, infecting people with malaria, using mustard gas on people, forced sterilization, giving prisoners different poisons, infecting wounds with bacteria and filling them with wood shavings and ground glass.

The Nazi doctor Josef Mengele was the prototypical “evil scientist,” known for his concentration camp experiments, with a particular focus on twins, mostly Jewish or Roma (“Gypsy”). Supposedly in the interest of studying heredity, the SS physician Mengele was responsible for such atrocities as removing organs from people without anesthetics, injections with deadly bacteria, dismemberment and others.

Not surprisingly known as the “Angel of Death”, Mengele collected the eyes of murdered victims for heterochromia research and attempted to prove through experiments the supposed resistance of Jews and Roma to a host of diseases.

circa 1940: Joseph Mengele, before he became known as ‘The Doctor of Auschwitz’ and ‘The Angel of Death’ for his pseudo-scientific experiments on inmates in Nazi death camps. (Photo by Keystone/Getty Images)

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9. Unit 731

Unit 731 was a secretive R&D unit of the Japanese Army that carried out horrendous experiments on humans during World War 2. Commanded by General Shiro Ishii, the unit experimented on an estimated 250,000 men, women and children. Most of the victims were Chinese, along with some prisoners of war from Russia and the Allies.

The forced medical procedures involved vivisections – cutting open subjects usually without anesthesia, unnecessary limb amputations, and removal of body organs like parts of brain, liver, lung and others. Victims were also subjected to biological warfare, frostbite testing, forced pregnancies, and even weapons testing by grenades or flamethrowers.

Trinity Site – 0.016 second after explosion, July 16, 1945. The highest point of the cloud in this image is about 200 meters high.

10. The Trinity Test

It’s hard not to put the world’s first nuclear test on such a list. In the mad rush to develop the atomic bomb and gain a military advantage in World War 2, America instituted the secretive Manhattan Project. This resulted in the Trinity Test, a detonation of the first-ever nuclear weapon in a New Mexico desert on July 16, 1945.

While the scientists were relatively confident in their work, there were some famous doubters who wondered if the bomb would even explode or if it would perhaps cause the end of the world as we know it.

Waiting for the bomb to go off, Nobel Prize-winning physicist Enrico Fermi, wagered others whether the bomb would just destroy New Mexico or the world, potentially setting the Earth’s atmosphere ablaze


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