How Do I Tell My BF???

About the smoking:

I noticed his dad has had a super bad cough for over 7 months now that won't go away. Being in pre-nursing, I know this is the beginning of lung cancer. One day it was so bad that I guess he was driving & was coughing so badly, he passed out & crashed into the car in front of him. Thankfully he was ok & I thought this was going to be a wake up call for him but it hasn't. They still do it. I've talked about this to my bf & have told him he should really talk to his parents on how he wants them to be around for a while, because at this rate I don't think his dad will make it too much pst his 50s. 

About the drinking:

They drink A LOT on the daily. So much there's no way their livers are going to make it for much longer. I've confronted this to my bf as well & he told me that his parents had a rough life when they were younger so that's why they do it. BUT that's not an excuse! Many people have had horrible experiences & lives and don't do that as an excuse. You should look at where you are now & be prideful & thankful for how far you've gotten. Since they start drinking at 5pm, they obviously can't drive past then. SO, when they want something from the store past that time, they'll ask my bf to drive & get them something. It annoys me because when we're doing something or relaxing, this is the last thing we want to do. Also, I found out that his family is on food stamps because his parents are "car dealers" who buy cars at auctions & resell them for a higher price. I don't believe this as hard working but scamming people, & I guess it really doesn't make a lot of money. BUT, one day his mom left a receipt in the car. I picked it up to see if I can throw it away, & I see she bought a bunch of necessary foods AND her alcohol with the food stamps (this PISSES me off). Not only that, but I've seen his dad plenty of times ask my bf or his brothers if they have money, & if they do, he'll go to the store & come back with a bottle of taquilla. WITH THEIR MONEY. 

I don't know how else for my bf to see what's going on here! My bf is so blinded because that's his family & he's used to it, but I can see all this & it really does worry me. I don't want something to happen to his parents & my bf have the burden of paying for everything & taking car of his little brother. It's just really bad, & I don't believe the excuses they give as to why they do these things. What can I do???