Pollutants may not be the only thing that get you in Rio's waters.

A Sky News reporter tweeted that an Olympic kayaker on a practice run capsized after hitting a sofa. The Olympic organizers are currently investigating.

It would hardly be a shocker if someone did encounter a rogue sofa. Photos of Guanabara Bay in the run-up to the Olympics showed all manner of trash and furniture in the waters.

In fact, it's not the sofas that are the real hazard. The water quality in Rio is so poor that scientists recommended athletes keep their mouths closed to avoid ingesting it.