The only way to truly test purity is to send it off to a lab. In lieu of that, this is what i would do: Test it with every reagent you have. For instance, with 0-D$eMT you could hit it with Liebermann (turns black), Mandelin (turns dark green), Marquis (turns reddish orange) and Froehde (turns green). Those colors are if you use Bunk Police reagents, not sure about others. If it passes all those it definitely has 0-D in it, but that still doesn't mean it doesn't have adulterants in it. So you hit it with the f3nt strip. Comes up positive? hit it again with more powder this time. Still positive? WHY RISK IT. Maybe its a false positive or maybe its f3nt, either way it's not worth it imo. But if the strip comes out negative, then you do the allergy test. People do this in different ways. Most just put a tiny dusting on their tongue and wait like four or so hours to make sure there's no reaction. Aside from allergies, some ch3ms that could be adulterating your stuff are highly active in micrograms and also take hours to kick in. If it's not something that's active in micrograms you shouldn't feel anything whatsoever. For best HR, i would recommend doing this again with a slightly higher dusting and waiting at least a day. And after that i would slowly titrate up both to be sure you're not going to have a reaction as well as to get better acquainted with a new ch3m. With 0-D in particular the come up can take up to four or five hours so don't redose during same day until you are sure what a certain amount will do over the course of a day. Psychonautwiki is also an invaluable resource you should check out if you haven't already both for dose recommendations and HR stuffs. Stay safe!!
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