Well, the "fuel" there is maybe 20% propane. Not so bad really. It is a very low temperature boil, unlike butane, so the lighter will work on a cold day.
When water is ice, butane is liquid.
That is the main thing about pure butane, or n-butane, and even they do call it food grade butane. They ship all kinds of food slurry around the factory with it, etc. It makes it so easy to work with. Low pressure at room temperature, easy to make liquid state and pour it around cold.
So, that is why a lot of plant extraction is carried out with 99.9% Butane. It is totally inert. I just read about all the extracts of paprika, you can get controlling low temp vs low pressure.
IAC, there is nothing on the market between the lighter fuel cans and a 14# tank, (LP5) of the pure stuff. I just got a case of Vector 4x. 2 cans will do 1 oz.
The pure stuff is for closed loop, solvent recovery systems. It is a main-stay for perfume extracts.
Hey, anyway. This is no joke. Don't burn up.
ALWAYS work it outside.