About the Data : Data FAQ

[see also Test Types & Data FAQ, Testing Links, and and Testing Statistics]

1. What is a GC/MS?
2. How are the ratios measured?
3. Why don't you display percentages instead of ratios?
4. Why don't you have actual quantities of each substance?

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1. What is a GC/MS?
   Please read the introduction to the GC/MS on the Test Types page. The GC/MS is an expensive set of instruments which are used to determine the contents of the pills tested by DDL (all of the results from MAPS, DanceSafe, and EcstasyData.org). The GC/MS by itself cannot determine quantities of constituents, only the relative amounts of detected substances. Many substances are not detected by DDL's GC/MS test because their molecular masses do not fall within the operating range of tests performed or the molecules disintegrate inside the test apparatus.
   
   The Mass Spectrometer used by our primary lab is the Hewlett-Packard 5973 MSD. Now sold as the Agilent 5973. See Agilent's GC/MS Systems and Agilent 5973.
   
   
   
2. How are the ratios measured?
   The ratio numbers which are displayed with most of the results from DDL (Drug Detection Laboratories) are determined by simply estimating the heights of each peak on the GC/MS output chart. Take a look at the the example GC/MS output chart below:
   
   
   Example of DDL's GC/MS Output
   
   This example shows two major peaks marked "A" and "B". Peak B is marked at "72" along the horizontal axis with a height approximately '3300' or so. Peak A is at "114" along the horizontal axis and somewhere over 10,000 along the vertical axis. The horizontal axis represents the molecular weight of the fragment measured and the vertical axis represents the relative amount of that fragment in the test.
   
   The lab computes the ratios by simply taking the tallest peak and comparing the shorter peaks to it by eye. In this example, Peak "A" is about 3 times as high as peak "B", so the ratio would be: 3 to 1 or:
   

   Substance "A" :	3
   Substance "B" :	1

   
   Reading a GC/MS chart can be complicated, and requires experience and knowledge of how the chemicals react inside the GC/MS. Many chemicals break apart inside the system and what appear to be individual peaks may be one substance broken into multiple sub-components. In this example, for instance, its possible that Peak 160 and Peak 174 are the same parent chemical with a small (14 weight) piece breaking off a majority of the molecules.
   
   Its extremely important to note that the relative ratios cannot be used to determine the quantitative contents of any of the substances found in the tests. It is also important to remember that each chemical has a different active dosage range. If a test determines that a tablet contains equal amounts of MDMA and methamphetamine, that would mean that the primary psychoactive effects of the tablet would likely be from the methamphetamine since it is much more potent than MDMA.
   
   
   
3. Why don't you display percentages instead of ratios?
   We feel it is misleading to display the substance results as percentages because not every component of a tablet is included in the GC/MS results (fillers, binders, etc) and the ratios of the identified compounds are only rough estimates. We have chosen, at this point, to use the more arcane ratio notation so that new visitors will not mistakenly assume that the amounts shown can be used to determine the amount of a substance in the displayed data.
   
   A wide range of substances cannot be detected using the GC/MS testing done by DDL. When we surveyed non-experts as to what they thought "50% MDMA, 50% caffeine" would mean, they often made the mistake of assuming that it MDMA and Caffeine each made up 50% of the weight of the tablet or that there was some way of extrapolating from the percentage to a quantitative value of the amount of MDMA or caffeine in the pill. A 1 to 1 ratio could be represented validly as 50% to 50%. There is no way of knowing (from the data we receive from the lab) whether there is 1mg of each substance in the tablet or 100mg of each substance in the tablet. While the ratio notation is confusing and may baffle some visitors, we hope it will lead to less mistaken assumptions about the pill contents.
   
   
   
4. Why don't you know (or display) actual quantities of each substance?
   In the United States, the handling of Schedule I substances (MDMA, LSD, Cannabis, etc) is restricted to those with a valid DEA license. Forensic labs such as DDL and others require DEA licensure in order to operate. The DEA has made an unpublished administrative rule that licensed labs are not allowed to provide quantitative data to the public, reportedly for fear of providing 'quality control' to dealers and suppliers of black market products. The DEA and other government organizations around the US perform thousands of tests of street pills each year, yet only a tiny amount of info about a small number of tests are published, except as aggregate data that cannot be verified.
   
   Because of this, the information we receive from the laboratory testing only includes information about what known substances were found and in what ratios.