Y: That’s a hefty book there, Don. What are you reading?
D: It’s a history of Egypt, Yaël, and it’s full of fascinating details! Listen to this: ancient Egyptians used copper to sterilize wounds and clean their drinking water. They even wrote about it in one of the oldest known medical texts, the Smith Papyrus, which is over four thousand years old.
Y: Those ancient Egyptians were definitely onto something. Scientists today recognize that copper is antimicrobial. In other words, it kills microbes, such as bacteria, fungi, and viruses.
D: I’m surprised I haven’t heard of this before. After all, when you think of, say, a hospital, you think of steel and plastic. But even on those surfaces, germs will live for several days, which is why steel and plastic medical materials are cleaned so much.
Y: The neat thing about copper is that it’s essentially self-cleaning: it will always kill microbes, even once it’s old and green. And any virus or bacteria that lands on copper dies within hours, if not minutes. The copper kills them by releasing ions, or electrically charged particles. These ions are like cannonballs through paper: they smash through microbes’ cells, obliterating everything, even the cell’s tiny amount of DNA and RNA. And with the DNA and RNA gone, that microbe can’t mutate and become resistant to copper.
D: Wow. If copper is so powerful, though, why don’t we see it used medically, or just in everyday life?Y: Hard to say. It’s likely that we’re just used to steel and plastic, and copper can be expensive. But some scientists think hospitals will soon use more copper supplies—this metal’s not ancient history quite yet!