Chrisk-k
Correct me if I'm wrong. I've read somewhere that denatured alcohol fumes are extremely toxic and damage brain cells. I once used denatured alcohol but couldn't stand its smell.
Denatured alcohol is basically ethanol (albeit in a higher concentration), which is the same type of alcohol in beer, wine and other alcoholic beverages, to which other chemicals are added to render it undrinkable. At one time, Methanol (methyl alcohol) was added as a denaturant (hence the name "methylated spirits). Methanol is extremely toxic. Use of methanol as a denaturant is declining in favour of other chemicals, but it is still used by some manufacturers.
On the other hand, Isopropyl alcohol, which is used as the base for many acrylic paints, is more toxic than ethanol, but less so than methanol.
Inhaling the vapours is far less hazardous than actually drinking it. Assuming you use adequate ventilation, it shouldn't be a problem.