At least weekly, I remember that pirates stowed barrels of piss away so they could make detergent. Human urine has many uses, and all of them are horrifying

"Cabbage is the most medicinal vegetable."

"If you save the urine from a habitual cabbage eater, heat it, and bathe a man in it, you will quickly make him healthy with this cure. This has been tested. Also, if you wash babies with this urine they will never become sickly!"

-Cato the Elder, inventing golden baths before golden showers were a thing.

Explanation: Despite having a great many features which seem positively modern to our eyes, like public restrooms and clean water supply, other practices of the ancient Romans were less... intuitive to our eyes. Swishing fermented urine, for example, was used as a method of whitening teeth.

Worst part is, it works, though not nearly as well as any modern methods. It's the ammonia.

hmm almost like organic compounds break down into other compounds over time or with certain processes?

Explanation: Despite having a great many features which seem positively modern to our eyes, like public restrooms and clean water supply, other practices of the ancient Romans were less... intuitive to our eyes. Swishing fermented urine, for example, was used as a method of whitening teeth.

Worst part is, it works, though not nearly as well as any modern methods. It's the ammonia.

I don't want to know how much disgusting stuff is in what we use every day.

Like, we love to eat rotten milk in various forms.

Or a friend worked at a fish pond. All the fish guts were sold to cosmetics companies. That's basically what it means when some creme contains "natural fats".