The market for pure fentanyl is pretty small in comparison and anyone sourcing it is probably really careful with the dosing. We’re in agreement that mixing is the problem, the margin for error with fentanyl is pretty slim compared to heroin which itself is potent.
We had fentanyl in coke around here a few years back, like 4 people died and they were able to trace it back to one seller and he got a ton of charges; how that adulteration happened I’ll never know.
