Did the Romans Really Brush with Pee?

In ancient Rome, people had some unusual ideas about cleanliness—and one of the most surprising was their use of urine as a cleaning agent. Believe it or not, urine was commonly used as both mouthwash and laundry detergent. Thanks to its high ammonia content, it was an effective natural cleanser long before modern soaps and chemicals existed.

Romans would collect urine in large clay pots placed in public areas—essentially ancient pee collection stations. Fullers, the professional launderers of the time, used it to clean and whiten tunics and togas. They would soak the garments in a mixture of water and urine and then stomp on them, much like how grapes were once stomped for wine. The ammonia in urine broke down dirt and grease, making it a surprisingly effective stain remover.

But the use didn’t stop at laundry. Some Romans used urine as a mouth rinse, believing it could help whiten teeth and kill bacteria. While this might make modern stomachs turn, historical sources suggest it was a widely accepted practice. The ammonia likely did have some antibacterial properties—though certainly not by today’s hygiene standards.

Urine became so valuable that during the reign of Emperor Vespasian in the 1st century AD, a tax was placed on the collection and sale of urine from public urinals. This “urine tax,” or vectigal urinae, became a profitable state income source. In fact, when Vespasian’s son Titus questioned the dignity of taxing waste, the emperor famously held up a coin and said, “Money does not stink.” That phrase is still quoted today—proof that even pee can pay.

While modern cleaning and dental care have thankfully evolved, Rome’s resourcefulness serves as a fascinating reminder of how past civilizations made use of every available resource—no matter how strange it might seem to us now.

So the next time you’re thankful for minty toothpaste or a fresh load of laundry, just remember: the Romans walked so we could run… far away from their hygiene habits!