The PFOA/C8 can be released while cooking, scratched or not. It's well documented that the gas released can and does kill pet birds kept in the kitchen near the stove. It's associated with all kinds of health risks in humans, as well. A place to start:

http://environmentalhealthnews.org/archives.jsp?tn=1title,lede,description,text,subject,publishername,coverage,reporter&tv=pfoa&ss=1

I use cast iron or stainless or ceramic coated (enameled), period. The trick is learning how to understand cooking temperatures. I've come to the conclusion that the only people who "need" teflon pans are ones who don't know how to cook very well.

My naturopath recommends ceramic coated cast iron.

Non-stick cookware is made using a carcinogenic chemical called perfluorooctanoic acid (PFOA), which starts emitting toxic fumes that you inhale every time you cook with a non-stick pot or pan! At high temperatures, the coating of non-stick cookware will also break down into a chemical warfare agent known as PFIB, and a chemical analog of the WWII nerve gas phosgene!

http://www.mercola.com/Downloads/bonus/dangers-of-nonstick-cookware/report.aspx

I can't say the following with 100% certainty, with that out of the way, teflon is a polymer which is a repeating chemical unit. I assume once the surface structural integrity has been compromised on a teflon pan, it is now more prone to surface fragmentation. This results in increased surface area the polymer exposed to heat and therefore increased rate of degradation. The byproducts of decomposition are pretty harmful from what i have read up on it.

if it were not breaking down due to increased exposure to heat, i still would not want to ingest bits and parts of any cookware...

For non stick, buy these. Also, the product description has a pretty good write up why teflon pans are bad.

http://www.amazon.com/Frying-Ozeri-Ceramic-Non-Stick-Coating/dp/B004AMUELO/ref=sr_1_2?s=home-garden&ie=UTF8&qid=1314751569&sr=1-2