Silk Road forums

Discussion => Drug safety => Topic started by: bogben on June 14, 2012, 09:26 pm

Title: Chemistry Question
Post by: bogben on June 14, 2012, 09:26 pm
Here's one for any accomplished chemists out there.

A few years ago I watched DMT being tested with one of those field test kits that the police carry use and it tested very weakly positive for amphetamines. Can anyone explain this other than a false positive? That or the test flags up benzene rings which seems unlikely...
Title: Re: Chemistry Question
Post by: DwarfSeeker on June 14, 2012, 09:41 pm
i'm assuming you are talking about reagent testing. reagent testing doesn't really test for what something is, it tests for what its not.

true reagent testing involves usually a quite large chart of different tests.

on the Marquis test you'll see Meth and DMT pretty much show exactly the same reaction.
http://www.bunkpolice.org/wp-content/uploads/Marquis-Infographic61.jpg

Title: Re: Chemistry Question
Post by: bogben on June 14, 2012, 10:36 pm
thanks! thats been bugging me for some time.
Title: Re: Chemistry Question
Post by: Ben on June 15, 2012, 12:23 am
You should also keep in mind that these tests are only screeners - they give a decent indication of the presence of substances, but are not of evidence quality. A positive result may give a reason to arrest someone under suspicion of possession, but to proof possession in court, real analysis is required. 

Also, the marquis reagent test will respond to an endless list of perfectly legal substances. If you test dilute table sugar you'll end up with the same result as you would for DXM. It was developed to screen for MDMA and similar substances, where the reaction goes from blue to black. That indicaton is pretty specific, as is the color change for morphine/heroin, but beyond that it doesn't tell you very much.