I don't get it.
Why should he die from a heart attack?
Pure Diacethylmorphine (as explicitly stated) is not damaging to the body (like really toxic) - addictive of course and does stuff with your psych over time, but it's not like you get a heart attack because of
In case of an overdose suffocation would be the more probable thing
But as with all things, that's depending on dosage
You're solving the wrong problem. Legalize all drugs, and you get better quality control, lower prices, and almost completely eliminate the cutting issue.
No vendor cuts alcohol with fentanyl. In states where marijuana is legal, the pot you buy in dispensaries will not be cut with fentanyl. That pack of Camels you get at the store will never be cut with fentanyl.
People who are going to do drugs are going to get them however they can; making them illegal only creates a black market and problems like you describe. Just saying "don't do drugs" doesn't work, like Nancy Reagan found out.
I agree entirely that we should just legalize it but my efforts haven't changed that it's illegal just yet so if the reader has the luxury to abstain while we continue to work on the correct answer, I implore them to do so. And if not it's the usual advice about being careful, know your supplier, all that jazz.
Which is the difference between "don't do drugs" and what I said.
I'm gonna add here in a different comment I know of two people (adults goddammit, who shouldn't have to be buying their fucking weed illegally) who died to fentanyl laced weed.
And like you said, it makes no sense to put it in weed of all things but I have no explanation. I'm just telling you what I know.