Your Toothbrush and the Toilet: An Uncomfortable Truth

Every time you flush your toilet with the lid up, you're launching an invisible cloud of microscopic particles into the air. Scientists call it "toilet plume," and it's exactly as disgusting as it sounds. University of Colorado Boulder researchers discovered these particles rocket upward at 6.6 feet per second, reaching heights of almost 5 feet within 8 seconds of flushing.

If your toothbrush sits within 6 feet of your toilet, it's in the splash zone.

The Infamous MythBusters Experiment

When Jamie and Adam tested this phenomenon, they placed toothbrushes at various distances from toilets and let them sit for a month. The microbiologist's verdict? Every single brush tested positive for fecal bacteria—even the control brushes they'd stashed in the kitchen, nowhere near a toilet.

This unexpected finding revealed an uncomfortable truth: fecal bacteria is practically everywhere in our environment, not just from toilet plumes. It's on door handles, kitchen sponges, and yes, apparently floating around your entire home.

But How Worried Should You Actually Be?

Here's where it gets interesting. A 2021 Northwestern University study analyzed what's actually living on toothbrushes and found something surprising: the bacteria came overwhelmingly from mouths and tap water, not from human waste. Lead researcher Erica Hartmann put it bluntly: "It's reasonably unlikely to find bacteria from our poop on your toothbrush."

The toilet plume is real, and contamination does happen, but your mouth itself introduces far more bacteria to your toothbrush than any airborne toilet particles ever will.

Does Closing the Lid Help?

You'd think so, right? Unfortunately, a January 2024 study by microbiologist Charles Gerba proved that viruses still escape in the toilet plume even with the lid down. The lid reduces the spread but doesn't eliminate it. Those microscopic particles are incredibly persistent, remaining airborne for tens of minutes between bathroom users.

The good news: your immune system handles trace amounts of bacteria like this constantly. The bad news: there's really no escaping it entirely.

What You Can Actually Do

• Close the lid before flushing (it helps, even if it's not perfect)
• Store your toothbrush in a cabinet or far from the toilet
• Rinse your brush before use to wash away whatever settled overnight
• Replace your toothbrush every 3-4 months as recommended by dentists
• Don't share toothbrushes—mouth bacteria is actually a bigger concern than toilet plume

The 6-foot rule is based on solid science, but the actual health risk is minimal for most people. Your toothbrush faces bigger threats from being stored in a damp environment where bacteria multiply, or from simple wear and tear that creates crevices for microbes to hide.

So yes, toilet plume is real and your toothbrush probably has trace amounts of bathroom bacteria on it. But before you panic, remember: you've been brushing your teeth like this your whole life, and you're doing just fine.