Researchers from London’s Metropolitan University swabbed 27 cell phones of high school students for a variety of bacteria. All of the samples were contaminated with germs—more than 17,000 bacterial gene copies and over 20 different microbial species in total, the authors reported. Some of the most frequent contaminants included certain strains of Staphylococcus.

While the presence of Staphylococcus won’t necessarily give you a staph infection, some of the detected bacteria are certainly worrisome, according to Susan Whittier, director of clinical microbiology at New York-Presbyterian and Columbia University Medical Center. After all, who knows what could be crawling around in that bathroom?

'We’re not walking through a sterile environment, so if you touch a surface there could be something on that. There are lots of environmental contaminants,' Whittier told TIME.

That even goes for potty scrollers who take extra care to wash their hands before touching their device again. 'Toilet seats, handles, sinks and taps are covered in germs such as E. coli, which can cause urinary tract infections and intestinal illness, C. diff, which can result in diarrhea, and acinetobacter, which can cause a contagious respiratory infection,' university microbiologist Paul Matewele told The Sun.

Since this study’s sample size is relatively small, more research is needed before drawing any definite conclusions about the post-potty presence of bacteria on your device. The researchers hope that future studies will examine how bacteria found on the phones might spread infections and diseases, too.

Regardless, it can’t hurt to start washing your phone screen as often as you wash your hands (and after every visit to the loo!)