Nazaroff co-authored study that reveals humans emit about 37 million bacteria per hour
A recent study may give germophobic students yet another reason to dread going to lecture.
A joint study of indoor microbial composition by UC Berkeley and Yale University researchers found that human presence causes a significant increase in levels of bacteria and fungi indoors. The average human emission, the study states, is about 37 million bacteria per person per hour.
The study — entitled “Size-resolved emission rates of airborne bacteria and fungi in an occupied classroom” — was conducted by collecting and comparing air samples from empty classrooms, occupied classrooms and the outdoors. In samples from occupied classrooms, researchers found elevated levels of microbes shed from human skin and cavities and kicked up in floor dust.
“Whenever you’re in a densely populated space, you’re breathing bacteria coming from other people,” said William Nazaroff, co-author of the study and campus professor of civil and environmental engineering.