How pure is street heroin?
This article has been translated to English.
In street heroin, usually less than half the powder is heroin: of 68 published samples carrying a purity figure, half came in under 44%, and the range ran from 3% to 96%. That spread is the reason a dose that worked from one batch can be dangerous from the next, and it is a wider spread than cocaine or ketamine show.
What else is in it
Of 197 samples submitted as heroin, 96% contained something besides heroin, which sounds alarming until you see what most of it is.
The table below counts what came back alongside the heroin.
| Detected alongside heroin | Samples |
|---|---|
| 6-MAM | 148 |
| Noscapine | 148 |
| Paracetamol | 135 |
| Papaverine | 122 |
| Caffeine | 113 |
| Acetylcodeine | 111 |
| Unknown | 20 |
| Morphine | 16 |
6-MAM, noscapine, papaverine, acetylcodeine and morphine are opium alkaloids and processing products rather than adulterants, so their presence is a sign the sample came from poppy rather than a laboratory. Paracetamol and caffeine are the actual cuts, appearing in 135 and 113 samples, and the pair is common because caffeine lowers the temperature at which heroin vaporises.
Against a market where 96% of samples carry something extra and purity runs from 3% to 96%, the reagent set is not a formality. Marquis, Mecke, Liebermann and Froehde exclude the substitutions, and the strip covers what none of them can.
Reagents identify, strips protect
Marquis, Mecke, Liebermann, Froehde, Robadope and Simon's between them indicate opioids and rule out the substitutions, and the opioid kit carries the set. What none of them do at the concentrations that matter is detect fentanyl or the nitazenes, because those are active in microgram quantities and no colour change resolves that. This is the one substance where the strip is not an optional extra.

Test every dose, not every batch
Fentanyl and the nitazenes do not mix evenly into powder. One end of a bag can carry nothing and the other a lethal amount, which is why the advice for opioids is different from everything else on this site: strip each dose you intend to take, not one sample per batch. A strip costs about the same as a coffee and is the only test here that changes an outcome rather than a decision.
How to detect nitazenes · Full method for opioids · Is Froehde reagent reliable
Questions?
Is 6-MAM an adulterant?
No. It is a heroin metabolite and processing product, and its presence indicates the sample really is heroin from poppy.
Why is paracetamol in it?
It is a cheap bulking agent. Caffeine appears alongside it because it lowers the vaporisation temperature.
Will a reagent detect fentanyl?
No, not at the concentrations it appears in. Use strips.
How much does purity vary?
3% to 96% in the published samples, with half of them under 44%. Assume nothing carries over between batches, run the reagents on each new source, and strip every dose.
No test result can tell you a substance is safe. No substance is 100% safe.This article is published for harm reduction purposes. It does not encourage the use of psychoactive substances and does not replace medical advice.
