All the carbohydrates will be coated with Acrylamide or burnt to a crisp. Acrylamide is believed to be a carcinogen (Acrylamide is converted to a compound called glycidamide , which causes mutations in and damage to DNA) and shown to be in animal models.

Once you're frying, roasting, and grilling things at this temperature you are increasing cancer risk completely unrelated to any cooking materials involved. That's true of french-fries, bread, steaks and a zillion other things. It's why they're tasty (see Malliard reaction).

I certainly consider cast iron relatively safe, but it's polymerized unsaturated oil is likely to leach acrylamide and associated chemicals. It's just that compared to the food you're eating it's not relevant.

Hate to be the raving "seed oils are going to kill you" guy, but Acrylamide can be greatly reduced by swapping your vegetable-based cooking oil with something like tallow, lard, or coconut oil: https://pubmed.ncbi.nlm.nih.gov/27374529/

I see online a lot of talk of the temperature and off-gassing relationship. I've also heard that it's slightly misleading because it's temperature and time dependent, where the temperature risk has to occur in such a short period of time that it doesn't reflect cooking use. However, I could not find the off-gassing studies; do you have links? It seems like the temp of 340C most often cited, apparently from a DuPont study.

> When used properly pans shouldn’t get anywhere close to that temperature range

What frying pan when used properly doesn't get near 300 C? A pan surface temp of 200-250 C is nothing strange when frying a steak.

250C is quite a long way from 300C.

It’s the same gap was walking outside into 25f and 115f Aka below freezing to punch you in the face hot.