You may not know it, but not all the water in the toilet bowl goes down the pipe when you flush. Microscopic droplets are also sprayed into the air, many of which contain bacteria from fecal matter. Experts call these infectious viral droplets.
The amount of toilet aerosols that end up in the air, and the distance they travel, depends on all sorts of factors (like how strong the toilet flush is, how full the toilet bowl is, etc.). . The toilet bacteria were found at 25 centimeters above some seats and continued to adhere to surfaces for up to 90 minutes after flushing. And by surfaces, we don’t just mean the toilet seat itself. The particles could land on the bathroom vanity or on a toothbrush.
Can we get sick?
Truth is, we’ve never heard of someone getting sick from flushing, but you might be thinking about it. The thing is, there are many cases where people can’t identify who or what caused them a cold, flu, or other infection. And many viruses live in our poop.
Norovirus, which causes run-of-the-mill stomach viruses, is found in the feces and vomit of infected people. Therefore, it is quite likely that cases are transmitted via aerosols from the toilet plume. The same is true for other bacteria such as Salmonella, Shigella, E. coli, C. difficile and SARS.
What to do in public toilets
By now you are (hopefully) convinced to close the lid before flushing. But what about when you’re in a public bathroom? Not only do toilets rarely have lids, but a study showed that industrial toilets can generate up to 12 times stronger compared to domestic porcelain used in home toilets.
It would be hard to avoid that kind of spray unless we wear a gas mask or avoid going to a public restroom. But a few common sense steps can help reduce exposure. For example, we must not lean over the cup after unloading, we will stay behind and wash our hands with soap and water immediately afterward.