They're mentioned here on RatForum, and yes, they're fine to eat but avoid giving them the seeds.

http://www.ratforum.com/showthread.php?39486-Good-and-Bad-Food-for-Rats-amp-Ratty-Recipes

 

Peppers are fine!

One food that I didn't know was bad for them is cracked corn. It came in this food mix for woodland critters that my dad was feeding the deer in our backyard and the package said it was safe for small pets, so I gave my girls some. I also bought a little cob of it at my local pet store. They loved it so much but one day I just decided to check just in case and I guess it is known to cause some kind of cancer! I was mortified and immediately threw it all away.