What to do if you suspect your 13 yrs old child of smoking???

I think you should tell her that you have a suspision that she is smokeing, but dont tell her that its becasue you smell the smoke on her. then if she is smoking she will just cover up the smoke smell with perfume and gum or soemthing, thats what my friends always did! Please also keep in mind that maybe the people around her are smoking and she might not be. I daughter reeks of smoke after being at my mom's for an hour.