What does weed do to you smoking it out if a can?

It shouldn't do anything. From personal use, I do it all the time and it should really just defect the taste of the weed. I suggest getting a glass bowl, or a metal one.

(Edit: It also can give you alzimer's. And please don't correct me wrong on this I know it for a fact my friend got it from doing this a lot. I'd suggest just make a bong out of a 2 liter or something like that. Or just go buy a one hitter from your Glass store.)