Is teflon a poison if ingested? Nowadays, a lot of frying pans are made with a non-stick coating. That's usually teflon, or chemically speaking polytetrafluorethylene - $\ce{(C2F4)}_n$. Can you be poisoned if some of that teflon gets in your meal by scraping the pan or in any other way? And if so, what happens (chemically speaking) in your body after ingestion?
I hope I am not breaking any rules of this forum by directly quoting, but here you go:

"The cold polymer is harmless on ingestion, in contact
with the skin, or implanted in living tissues. When
heated above 250° C. it begins slowly to give rise to
small amounts of decomposition products, some of
which are toxic.
The accidental inhalation of fumes from the overheated
polymer by workmen produces an influenza-like
illness which has been described elsewhere. The
illness follows a latent interval of a few hours and
resolves within a day or two with no subsequent illeffects.
This may happen, for example, when the
polymer is heated to comparatively high temperatures
(350-400 C.) in an oven, an extruder, or some other
equipment used to fabricate it, but it is easily prevented
by the intelligent use of exhaust ventilation."

In: Harris, Kenwin. “Toxicity of Polytetrafluoroethylene.” British Medical Journal 1.5285 (1962): 1146.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1958415/pdf/brmedj02864-0082a.pdf