You should take a look a this too.
https://np.reddit.com/r/vancouver/comments/9wbz1t/complex_reasons_fentanyl_mixes_are_the_first/
>There is nothing law enforcement can do so society must decide how it wants to deal with this problem. There has been a linear progression from Oxycontin to Heroin to Fentanyl which snuck opiates back into the public eye. Due to the money to be made in a world where the jobless are so downtrodden, open air drug markets are prevelant and only getting worse.