I really realized that hygiene is mostly a habit when I visited a densely populated but quite poor country. A place where we were warned not to drink tap water or ask for ice cubes in our drinks. We followed all the rules, yet as soon as our plane landed, we rushed straight to the restroom.
After a few uncomfortable days, we adapted enough to even dare eat street food, which had seemed unthinkable before. Saying that the health authority could have shut down every vendor and shop in the country is an understatement. Yet people lived and thrived, not only drinking tap water without worry, but having to get their fluids from just about anywhere. It’s definitely not the healthiest way to live and carries risks, but when there’s no other choice, you do what you must.
So after that, I worried much less about disinfecting at home and ditched harsh chemicals long before becoming a mom. When our little girl arrived, I became even more mindful about avoiding toxic substances and didn’t try to make her environment 99.9% bacteria-free.
The Invisible Reality Captured in Photos
I’m not saying I overthink this, but when I saw these photos, I definitely agreed it’s a good idea to close the toilet seat lid before flushing.
A survey of 2,000 adults in the UK found that 55% don’t consider this routine important, even though 72% say they focus more on hygiene now than ever since the pandemic.
Commissioned by Harpic, experts examined what’s really in our toilets. They found that even after multiple flushes with clean water, potentially harmful bacteria and pathogens remain. To prove this and make it visible, researchers used slow-motion footage with a special camera.
This allowed them to capture aerosols—tiny droplets and bacteria floating in the air—whose paths became clearly visible. The images show that droplets from flushing don’t just land on nearby surfaces like toothbrushes and towels, but can even reach the faces of people using the restroom.
So why don’t we automatically close the toilet lid?
Among respondents, 47% said they never realized the health risks involved in using the restroom, while 15% admitted they simply forget this step. But after seeing the photos, opinions changed dramatically: 95% said they would definitely close the lid before flushing from now on.
It’s Even Worse with Urinals
Previous research also highlighted the dangers of flushing. A report in the Physics of Fluids journal revealed similar findings for men using urinals. Simulations showed that flushing a urinal can be much worse than flushing a traditional toilet, with aerosols reaching users in a fraction of the time. Check out our article on toilet paper habits for more context.
The study’s author explained that particles spread outward during flushing, with over 57% escaping the urinal. While sprays from a regular toilet rise higher, they take longer to reach a person. According to the model, droplets stay airborne for about 1 minute before settling and either dying off or multiplying, depending on the environment.
