“It all started with an enquiry from a nurse,” Dr Karl Kruszelnicki told listeners to his science phone-in show on the Triple J radio station in Brisbane. “She wanted to know whether she was contaminating the operating theatre she worked in by quietly farting in the sterile environment during operations, and I realised that I didn't know. But I was determined to find out.”
Dr Kruszelnicki then described the method by which he had established whether human flatus was germ-laden, or merely malodorous. “I contacted Luke Tennent, a microbiologist in Canberra, and together we devised an experiment. He asked a colleague to break wind directly onto two Petri dishes from a distance of 5 centimetres, first fully clothed, then with his trousers down. Then he observed what happened. Overnight, the second Petri dish sprouted visible lumps of two types of bacteria that are usually found only in the gut and on the skin. But the flatus which had passed through clothing caused no bacteria to sprout, which suggests that clothing acts as a filter.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1121900/File this under things we didn't really need to know.
