Unsurprisingly, the list includes the circus act that involves spraying fuel from your mouth. Truth be told, it should probably be on the list of just plain dangerous things to do, period. Let's go through some of the steps involved in fire breathing, just to reiterate how totally bonkers it is that people still happily perform the trick today.
First off, fire breathers put some sort of fuel in their mouth, be it kerosene, gasoline or an alcohol-based flammable liquid. Then they spray the fuel in a fine mist — you know, like the kind a fancy shower might produce (that's the most relaxing description I could think of for spit-taking flammable liquids). Next, they'll ignite the mist with a small hand-held torch. Lighters and matches are not trustworthy enough for fire breathers, which is saying something.
We probably don't need to go into every aspect of danger when it comes to fire breathing, but let's acknowledge a few hazards to the performers: The flame can blow back into their mouth, they can get chemical pneumonia from inhaling the fuel and they can even poison themselves. And there's danger to the audience, too: The flame can easily shift with no warning and burn whoever is watching — or even set fire to the property.