Bit of a backstory - DS16s best friend moved to a not so nice part of town a couple of years ago (burglaries, drug use amongst other things). DS has visited him regularly and had sleepovers there and at ours. DS' friend has always been nice enough, but we now don't know any of the other kids they're hanging around with. I saw a couple of the girls recently, and they were a bit rough looking (yes, I know how snobbish I sound). Since DS finished GCSEs last month he's been over there a lot more. We noticed that when we picked him up or he came home he'd be reeking of deodorant and always chewing gum, so our suspicions were aroused. Both DH and I a very anti smoking and have never wanted to try it (I always hated breathing in other people's smoke, the smell, the cough, the yellow fingers etc.). DS knows about all the dangers.
Anyway, he came back today and DH checked his bag. He found a lighter and said that the whole bag stank of weed.
He's got a full time summer job starting next week which means very early mornings and days labouring for a builder so he's not going to have much opportunity to see his friends much, but it also means he'll have money to spend and if he wants to buy cigarettes he's legally able to.
I know he's 16 and I can't control what he does like I used to when he was 6, but just looking for some advice on how to handle this. I'm for the gentle talking to approach while DH goes in all guns blazing. I also know it could be a hell of a lot worse, so apologies if anyone thinks this is trivial.