It all depends on the type of stain and the surface it is on.
Grab an empty spray bottle. put a bit of soap in, and abit of shampoo. fill it with cold water. spray the mixture onto the spray and rub gently with a cloth and the stain fades completely so there is...
soak your hands in a sulution of half water and half bleach for about 5mins
Yes
Coal tars from the other ingredients in the smoke -- the stuff that kills you, actually.