In a new experiment using bright green lasers and camera equipment, scientists from the University of Colorado Boulder were able to see airborne particles invisible to the naked eye. These particles are sprayed into the air when the lidless toilet is flushed. While researchers have known for more than 60 years that these tiny particles are released into the air during flushing, this study, published in Scientific Reports, is the first to directly visualize them, enabling measurements of how fast and how far the particles travel.

Here's the worrying part: These particles can transmit pathogens, including bacteria, viruses or other microbes, that can cause disease. In just eight seconds, the particles shot out at a rocket speed of 6.6 feet per second, reaching 4.9 feet above the toilet, with larger droplets appearing to land on the surface within seconds, while smaller droplets, the scientists report. The drops seem to linger in the air for a period of minutes or even longer.

The researchers point to the importance of understanding the effects of these particles to mitigate exposure. "If it's something you can't see, it's easy to pretend it doesn't exist. But once you see these videos, you'll never think about toilet flushing the same way again,"