Jasmine Roberts collected ice samples from five restaurants in South Florida for her award-winning project-from both self-serve machines inside the restaurant and from drive-thru windows.
She then collected toilet water samples from the same restaurants and tested all of them for bacteria at the University of South Florida.
In several cases, the ice tested positive for E. coli bacteria, which comes from human waste and has been linked to several illness outbreaks across the country, ABC News reported.
"These [bacteria] don't belong there. It's not cause for panic, although it is alarming because what she found is nothing new. You're not more likely to get sick now. But she's done us a favor by sounding the alarm," Dr. David Katz, medical contributor to 'Good Morning America' said.
Both Roberts and Katz said that the ice is likely dirtier because machines aren't cleaned and people use unwashed hands to scoop ice.
Toilet water is also surprisingly bacteria-free, because it comes from sanitized city water supplies.
Roberts got interested in the project after reading a newspaper article about bacteria in airplane water and decided to do something similar. Plus, she said, all of her friends chew on ice, and it drives her crazy.