I was reading yesterday that the trend to legalize marijuana and medical marijuana had cut heavily into the profits of the cartels, and so they started bringing in heroin instead. They've found a way to make a higher purity and combined that with price cuts, targeting those that are addicted to pain meds, which are very expensive on the street. Now the addicts have a much cheaper high but the high purity is too much for them.
I saw numbers somewhere that half of Colorado'[s pot industry is legal and taxed, now, the rest isn't. That had to cut into the cartels' market, but If I was them, I'd be working a chain of franchises and supplying them in the states where its legal, above board. Why not? They'd still make money and gain market share.
As for the heroin, It isn't just a question of purity, but it is being cut with fentanyl, and the combination is potentially lethal. I know a kid who is in a CDU now (thankfully) who was rolled out of a pickup cab at a convenience story and hit the ground, clinically dead. The clerk gave him CPR, ER administered naloxone, and they got him back. (God must not be done with him yet.) He said he'd been told (also from sheriff's detective) that the fentanyl it was cut with was the reason he OD'd.