Chins ATE Paper Towel!

So, last night I apparently left a dry paper towel somewhere while I was cleaning my boys' cage. I couldn't find it, and it seemed like it completely disappeared. But, this afternoon, I saw it in their cage! It had urine on it, and pieces of it were missing. About 80% of it was still in-tact, and it was only a single sheet. I'm not sure if only one got to it, or both of them did. I feel extremely guilty.

Is there anything I should watch out for? Is this worth a trip to the vet? What...

Chins ATE Paper Towel!