Sure fluorine is extremely reactive but once a F is bonded to a C, it's quite hard to dislodge. To remove that bounded F you need a really strong oxidant like o

Sure fluorine is extremely reactive but once a F is bonded to a C, it's quite hard to dislodge. To remove that bounded F you need a really strong oxidant like ozone. Chlorofluorocarbons were used as propellant in sprays and asthma pump because they didn't react with the active substances. The presence of fluoride in a disproportionate number of poisons (FOOF excluded) is due to the fact that as far as biological binding site are concerned it's almost like a really heavy hydrogen but metabolically it protect that carbon from being the target of an enzyme¹. This enable a toxic molecule that would be quickly metabolized to stay active long enough to do some damage. It's important to note that the presence of a C-F bond doesn't make a molecule inherently toxic, it just make it harder to metabolize when that bond is placed at the target of an enzyme. 1- https://www.sciencedaily.com/releases/2019/03/190305112830.htm https://www.sciencedaily.com/releases/2019/03/190305112830.h...