I read somewhere long ago back in the midsts of can't find the reference for shit time that the fentanyl wave had missed the "west" (I think) coast cos of the prevelance of tar and difficulty of mixing fent into tar. Of course it can be done .. but it ain't gonna be done by some street dealer with a bag of tar and a bag of fent.
If you're worried get piss strips. They're really really cheap .. you'll get loads and they'll tell you if you've been using (some types) of fentanyl.
You even buy em on amazon .. though I recommend you find a non-profit harm reduction place. Don't feed the beast and all that!
