The 10 Cruelest Human Experimentation Cases in History

Guatemalan Syphilis Experiment

For more than two years in the middle of the 20^th century, the United States worked directly with the health ministries of Guatemala to infect thousands of people with a range of sexually transmitted diseases, above all syphilis. Since they wanted to do this without the study subjects knowing about it – after all, who would give their consent to being injected with syphilis? – it was decided that the experiment should take place in Guatemala, with soldiers and the most vulnerable members of society to serve as the guinea pigs.

The Guatemalan Syphilis Experiment (it was not given an official codename or even a formal project title) began in 1946. It was headed up by John Charles Cutler of the US Public Health Service (PHS). Despite being a physician himself, Cutler was happy to overlook the principle of ‘First, do no harm’ in order to carry out his work. Making use of local health clinics, he tasked his staff with infecting around 5,500 subjects. Most of them were soldiers or prisoners, though mental health patients and prostitutes were also used to see how syphilis and other diseases affect the body. Children living in orphanages were even used for the experiments.

In all cases, the subjects were told they were getting medication that was good for them. And, while all subjects were given antibiotics, an estimated 83 people died. In 1948, with the wider medical community hearing rumors of what was being done in Central America, and with the American government wary of the potential fallout, the experiments were brought to an abrupt end. Cutler would go on to carry out similar experiments in Alabama, though even here he stopped short of actually infecting his subjects with life-threatening diseases.

It was only in 2010, however, that the United States government issued a formal apology to Guatemala for the experiments it carried out in the 1940s. What’s more, President Barack Obama called the project “a crime against humanity”. That didn’t mean that the victims could get compensation, however. In 2011, several cases were put forward but then rejected, with the presiding judge noting that the U.S. government could not be held liable for actions carried out in its name outside of the country. A $1 billion lawsuit against the John Hopkins University and against the Rockefeller Foundation is still open.

Mengele’s Twins

A world at war gave the Nazi regime the ideal cover under which they would carry out some of the most horrific human experiments imaginable. At Auschwitz concentration camp, Dr Josef Mengele made full use of the tens of thousands of prisoners available to him. He would carry out unnecessarily cruel and unusual experiments, often with little or no scientific merit. And, above all, he was fascinated with twins. Or, more precisely, with identical twins. These would be the subjects of his most gruesome experiments.

Mengele would personally select prospective subjects from the ramps leading off the transport trains at the entrance to the concentration camp. Initially, his chosen twins were provided with relatively comfortable accommodation, as well as more generous rations than the rest of the inmate population. However, this was just a temporary respite. Mengele’s experiments were as varied as they were horrific. He would amputate one twin’s limbs and then compare the growth of both over the following days. Or he would infect one twin with a disease like typhoid. When they died, he would kill the healthy twin, too, and then compare their bodies.

Gruesomely, the records show that on one particularly bloody night, Mengele injected chloroform directly into the heart of 14 sets of twins. All died almost immediately. Another infamous tale tells of Mengele trying to create his own conjoined twins: he simply stitched two young Romani children back-to-back. They both died of gangrene after several long and painful days. Mengele also had a team of assistants working for him, and they were no less cruel.

Nobody will ever know just how many children or adults were victims of Mengele’s experiments. Despite being meticulous record keepers, the Nazis kept some things secret. Tragically for his victims and their relatives, Mengele never faced justice for his actions. He was smuggled out of Europe by Nazi sympathisers at the end of the war and lived for another 30 years, in hiding, in South America.

Where did we find this stuff? Here are our sources:

“Unmasking Horror: A special report.; Japan Confronting Gruesome War Atrocity”. Nicholas D. Kristof, The New York Times, 1995.

“Little Albert regains his identity”. American Psychology Association, 2010.

“Unit 731: Japan discloses details of notorious chemical warfare division”. Justin McCurry, The Guardian, April 2018.