Ask a germ expert: How filthy is your cell phone case?

Of all of the inanimate objects I touch everyday, just two of them are basically extensions of my hands: my BKR bottle (hydration, y’all!) and my iPhone (duh). And that’s precisely why I had turned a blind eye as to whether these items are covered in germs. But then I found out about how moldy your water bottle can get, so… I figured it was time to come face to face with my iPhone case (which has definitely touched surfaces in public restrooms). I decided to call the Germ Guy, Jason Tetro, a microbiologist and author of The Germ Files, to ask: How dirty is your cell phone case? He would definitely have the dirt.

Tetro’s take? Think of your cellphone case as your purse. They acquire the same germs, since you carry both pretty much everywhere you go. “There have been studies done on purses, and they have bacterial contamination,” he says. “In all likelihoood, your cellphone case is going to have microbial contamination, too. It doesn’t matter what material it is.” Yes, your phone case is germy.

But here’s the thing—these germs aren’t so scary, so there’s no need to go frantically shopping for a new case. “When you start looking at the different types of bacteria, it gets a little bit less worrisome,” says Tetro. “When you look at the purses, the majority of bacteria that grows or finds its way on them happens to be environmental, which makes sense. For the most part, we’re talking about harmless bacteria.”

With your phone case specifically, he says that most of the microbes on it come from you. “Your natural, normal flora is going to end up on it,” he says. And your body is already accustomed to its own bacteria.

“But I put my cellphone down in the gym! In the bathroom!” I point out. This is where things get a little more complicated. Obviously, the bacteria of many, many other people is present in this kind of environment. “If you happen to be in a a high-traffic area with a lot of pathogens—like a hospital, or a kitchen, or a gym—you can never be quite sure what you’re going to get,” says Tetro. “There’s probably not a problem 99.9 percent of the time, but no one wants to get sick, so it’s always better to have a proactive mentality.”

To clean that case, Tetro says you can just throw it in the dishwasher (if it’s dishwasher-safe) or use an antimicrobial wipe. “It’s not your phone case that’s the issue, it’s where you are that’s the issue,” he says. Put that phone down on the gym floor? Yeah, time to clean it. (Good to know it’s not as filthy as your desk.)

BTW, the germiest part of your car isn’t what you think—so here’s how to clean that seat belt. And this is what to know about bacteria on gym equipment (BRB gagging).