He asked a colleague to break wind directly onto two Petri dishes from a distance of 5 centimeters, 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.
Well I'll be damned!
Just keep your pants on I guess.