What gives ham hot dogs and bologna their pink color?

Meat processing companies have been (for years) mixing in this pink sludge as a meat substitute in their low end meats like hot dogs, bologna and ground beef. This was actually some big news story a while back. Pretty much, you don't want to be eating that stuff, ever. You should go to a real butcher and get decent sliced meats and dogs. It costs more but at least it's real meat.

This is one of those things where a scientist could say the mass consumption of this pink sludge has led to certain health problems but the time and energy it would take to LEGALLY link health problems to the meat companies would make it nearly impossible.