Engineers from the University of Colorado Boulder used laser lights to see just what happens when you flush a public toilet.

Stunning new video of bright green “toilet plume” particles highlight an invisible phenomenon that's easy to ignore, but might deserve more of your attention.

University of Colorado Boulder engineers studying the spread of fecal pathogens and health hazards associated with flushing pointed laser lights at a lid-less public restroom toilet, the same kind commonly seen in North American public restrooms, to illuminate rapid spreading tiny water droplets.

“We had expected these aerosol particles would just sort of float up, but they came out like a rocket,”  said Professor John Crimaldi, lead author on the study and head of the Ecological Fluid Dynamics Lab at CU Boulder. "Once you see these videos, you're never going to think about a toilet flush the same way again.”