It turns out that college kids aren’t the only party animals that show up for games of beer pong: Bacteria such as salmonella, listeria, staph, and e. Coli get in on the fun, too. Those are the findings from a group of Clemson University students who studied the pingpong balls used in games and found up to 3 million germs on them, reports the AP via the Houston Chronicle. And yes, lots of those germs ended up in the beer when dunked. "Ninety percent of bacteria are probably harmless, but by virtue of sheer numbers, you're taking a chance of getting sick," says the prof in charge of the study. (More beer pong stories.)