Pettenkofer's name is most familiar in connection with his work in practical hygiene, as an apostle of good water, fresh air and proper
sewage disposal. His attention was drawn to this subject by the unhealthy condition in Munich in the 19th century. Specifically he examined the field of hygiene and determined that there was a minimal amount of rigorous research. He was responsible for transitioning the field of hygiene into a research-oriented field. Many of his additions and plans for the city's sewage system are reflected today in the current sewage system layout. During his schooling he studied for a time under
Justus von Liebig where he applied his study of chemistry to the study of chemical reactions occurring within the body. This in particular focused on the study of the science of nutrition and the reactions in the body that consumed foods and produced the processes of the body. He further advocated for reform of the food production system used in Munich. He argued that the system for the study of proper cattle feed was more well developed than that for humans and recommended civic funding for studying proper nutrition. He proposed that this study of nutrition was important specifically for the poor and those in strictly controlled environments such as prison because they were most at risk for obtaining sub-par nutrition due to their limited control over their food consumption. He further advocated for the construction of more spacious living accommodations. He asserted that there was a strong link between proper circulation of "good air" through houses, adequate space for living, and the health of the occupants. His beliefs aligned significantly with the school of thought known as the
Miasma theory. He firmly believed that the causes of disease were related to the multitude of environmental factors that the people of Munich were required to live in. Air was of a particular interest to him and he continued to advocate for its relevance to the processes of disease, specifically the spread of
cholera. He was also a strong proponent of regular bathing and changing of clothes in its relationship to health through the further regulation of the heat of the body. He advocated that health was the collective responsibility of a city to behave as best they are able to further the health of the general population. In addition to the wide number of publications and lectures that he gave on the subject of public health Pettenkofer was also involved in the initiative to create an Institute of Public Health in Munich. He continued research into a variety of fields listed above as head of the Institute of Physiology in Munich from 1857 onwards. After numerous successful audiences with two of the kings of Bavaria he had helped found the first three hygiene departments. In 1879, he finally achieved his goal of the creation of a standalone Institute of Hygiene in Munich. This institution was larger than his previous accommodations in the department of Physiology and allowed him to continue to his research and to gather a large cohort of research students under his teachings. The founding of his Institute of Hygiene drew significant international attention and was considered a model for many later institutions including the
Johns Hopkins School of Hygiene and Public Health in Baltimore. During his career his position as a strong proponent of public health at times placed him at odds with his contemporaries, most notably
Robert Koch. During his career, Koch identified and isolated a large number of bacterial strains and was a supporter of the theory that these germs were the main causes of disease. This placed him at odds with Pettenkofer's broader approach to disease that involved many other environmental factors in addition to the activity of the germ of a disease. The two scientists conflicted most notably over the subject of
cholera. In one specific case, Pettenkofer obtained bouillon laced with a large dose of
Vibrio cholerae bacteria from Koch, the proponent of the theory that the bacterium was the sole cause of the disease. He consumed the bouillon in a
self-test in the presence of several witnesses on 7 October 1892. He also took
bicarbonate of soda to neutralise his stomach acid to counter a suggestion by Koch that the acid could kill the bacteria. He did not contract the disease, nor did he become unwell. This launched a shadow of doubt over Koch veracity about his claims that the
Vibrio cholerae bacteria is responsible for causing the cholera disease. ==Publications==