Max Joseph von Pettenkofer was a Bavarian chemist known for his research on practical hygiene and implementing many hygiene-related standards in German cities, including improving the state of drinking water, sewage disposal, and general cleanliness. While all of this work positively contributed to public health, it was also a result of Pettenkofer’s alignment with the miasmatic theory rather than the germ theory of disease. And even though Pettenkofer did not deny the existence of bacteria, he thought they weren’t enough to cause sickness and had to be accompanied by bad living conditions, miasmatic air, and dirt in general. This belief made him at odds with Robert Koch, the discoverer of the bacterium responsible for cholera outbreaks and proponent of the germ theory of disease. The two scientists did not see eye to eye with each other on how to deal with German cholera outbreaks in the 1880s, which only made things worse.
Pettenkofer was so adamant that Koch was wrong that he decided to perform a perplexing experiment on himself in 1892 (when he was 74!). To prove that cholera could not develop without poor hygiene and subsoil rather than drinking water, he decided to drink a cholera bouillon laced with bacteria isolated from the stool of a person who had already died of that disease. To make sure his experiment was viable, he decided to do it in front of an audience and obtained the sample from Koch himself. He had also emptied his stomach beforehand and neutralized any leftover acid with sodium bicarbonate.
How this fantastic example of self-experimentation ended? After experiencing watery diarrhea for a week, Pettenkofer stated that he did NOT come down with cholera, and his symptoms were associated with something else. In reality, he contracted a mild case of cholera and was probably saved from death by the fact he already had had contact with the disease a few years earlier. When asked why he was willing to risk his own life, he stated “I would have looked Death quietly in the eye for mine would have been no foolish or cowardly suicide; I would have died in the service of science like a soldier on the field of honor.”
You can read more about this and other self-experiments in Who Goes First?