Why You Should Never Flush With The Toilet Seat Up
If you don't close the toilet lid before you flush, you might want to start. As it turns out, flushing the toilet with the lid up is incredibly unsanitary. When you flush, a toilet plume is released into the air, which is as bad as it sounds — it sprays microscopic bacteria and waste particles all over the bathroom (via Today). In fact, bacteria and germs emitted from the toilet plume can linger in the air for as long as six hours and land on nearby objects like your soap, towels, or even your toothbrush.
While modern toilets are designed to limit the amount of toilet plume released into the air, the toilet bowl itself is covered in bacteria and fecal particles, which become aerosolized when the toilet is flushed. Closing the lid before flushing can significantly reduce the amount of droplets and particles that are emitted. If you're using a public toilet that doesn't have a lid, simply refrain from leaning over the toilet when you flush.
Toilet plume and the spread of disease
According to a scientific review article published in the American Journal of Infection Control, toilet plume could play a role in the transmission of infectious diseases. While the article suggests that harmful bacteria in the toilet plume could potentially aid in the spread of viruses and disease, more research is needed to determine whether or not this is true. Either way, it is fairly difficult to get infected with a virus or disease from the mere presence of a toilet plume to begin with.
"In order to actually get infected, you would have to ingest bacteria that were still alive and ingest them in sufficient numbers to cause an infection," microbiologist Dr. Janet Hill told Today. Even if bacteria lands on your skin or your clothes, you will still need to ingest it in order to get infected. That's why the best way to protect yourself from harmful bacteria from toilet plume is to wash your hands (via Business Insider). However, closing the toilet lid when you flush couldn't hurt either.