I agree with ellynn. I used to smoke a lot when something is bothering me or when I'm really stressed out. For your situation, yes you should bring it up to him but try to find away to make it not so confronting. I'm sure he knows that it bothers you but you need to also tell him how much it hurts you to see him polluting himself that way. What worked with me was when someone said, "I love you. Watching you smoke is like watching you slowly killing yourself. Take the time to slow down on how much you smoke. I'm not asking you to quit instantly. jUst try to cut down." I thought about that really hard and this came from my mom a few weeks ago. With the help of her talking to my bf and asking him to help me as well ... it broke my heart to see that I was hurting them with my own bad habits and I stopped. See if that works for you. It's going to be a little harder for him only because his buds are smoking as well, huh?