You’ve probably heard about the kits you can use at home to check the contents of black-market drugs. You might wonder what the fuss is about drug checking is when you can already do it yourself.
You can buy colourmetric reagent testing kits from internet retailers at low cost (like here or here). Kits come with detailed instructions but basically you combine a chemical ‘reagant’ with the substance you’re checking. The mix then reacts and changes colour. Then you compare this colour with a colourmetric chart that tells you the most likely contents of the substance. You can use multiple tests with different reagents to improve the overall accuracy.
Even doing mutiple, careful tests though, there’s a limit to how much information you can get from these test kits. They are much better than nothing, and also not good enough.
So what’s wrong with colourmetric reagent testing kits? The list is pretty long: they are only indicative about what the substance is most likely to be; they provide no information on the non-drug components which may be present in a sample; they give misleading results for drug mixtures; they do not provide reliable information on drug dosages or purity; they give results that are open to subjective interpretation; and they contain hazardous chemicals (more detail). A study conducted in South Australia compared reagent test results with results from laboratory analysis (using Gas Chromotograhy-Mass Spectronomy). Only 11% of pills with combinations of illicit substances had both substances correctly identified by the reagent test.
Much more precise testing procedures use laboratory technologies like chromatography and/or spectrometry. A 2009 feasibility study for the Victorian government assessed the different kinds of technology available for an illicit drug monitoring system. The report describes how
'chromatography involves the separation of a drug compound into its separate chemical components, thus permitting the identification of individual substances in complex chemical mixtures. It is a relatively fast technique, taking as little as fifteen minutes, possesses high-level reliability and produces quantitative and qualitative results that can be used immediately in on-site testing locations. Mass spectrometry involves the conversion of a drug or drug metabolite into charged particles and the mass-to-charge ratios of the particles generated create a pattern that provides a positive identification of the drug.'
A review conducted in 2006 for the Australasian Centre for Policing Research recommended that 'if it is deemed desirable to accurately determine the content and quantity of substances present in ecstasy pills as part of a harm reduction approach, then these are the 'gold standard' approaches that should be used.'
Let’s go for gold