Reply #27: not any more than driving a regular car makes you smell like gasoline...

[garybeck]

if you sand in front of the exhaust, you might get some fumes in your clothes, regardless of what you're burning. otherwise you're fine

however I will say this. if you run on veg oil, you will have to collect oil from restaurants, filter it in your home and pour it into your tank. some of this can get messy and you may end up smelling like vegetable oil, not when you're driving, but when you're messing with the oil, transporting it, etc... don't wear your nice clothes!