I left a non-stick pan on the stove for an hour I was boiling something and I left them on the stove for about 1 hour. The pan was full and starting to boil at the start of the time, and when I got down and realised it was totally empty. The gas was on full heat, and since it's gas it does get really quite hot. There is still fumes 3hrs later - I don't think the brand was Teflon, but would it still have been using the same material? And basically, should I be worried, or is most of the internet stuff mostly scaremongering?
Hope this isn't too off-topic!
When heated to a high enough temperature (260C - 350C) Teflon (polytetrafluoroethylene) degrades into fumes that can cause flu-like symptoms. If you haven't experienced these symptoms and have aired out the room you should be fine. Even if you had these symptoms, they should clear up by themselves fairly quickly.