I recently came across this whitepaper the other day, which was created by a Massachusetts company known as MCR Labs who has started to look at the science behind how vaporizers dose cannabis for medical patients. As someone who has written in the past about when a vaporizer bowl is finished (see my article on overvaping cannabis), I was curious to see what a scientific study would find. Known as the “Vape Ex Program”, President and founder of MCR Labs Michael Kahn has stated that

…the team set out to provide [medical marijuana] patients with quantitative data to help them answer some of the most common questions asked by patients when vaporizing. The main questions that he wanted to answer include “How much of a given cannabinoid is being consumed with each draw,” “how many draws before all the beneficial compounds have been extracted,” and “What is left behind when you finish vaporizing?”

Using an MFLB (Vaporblog review here) as the test unit, Kahn’s team discovered that

…the active cannabinoids were consumed after 40 draws, at a rate of 0.3 mg of tetrahydrocannabinol (THC) per draw. It’s important to note, however, that the cannabinoid profile was “significantly altered” over the course of 30+ draws. There was a decline in maximum THC (a theoretical equation that accounts for THC and THCA) and an increase in cannabinol (CBN).

This means that it took 40 puffs for all the THC to be vaporized in an MFLB (take a look at the chart above), and as THC decreased over time, CBN concentrations increased. Of course, since different vaporizers produce varying amounts of vapor per puff (I find the Ascent and Solo to provide thicker hits than the MFLB), while others (like the Volcano) use a bag system, so expect the results to vary significantly by device (and thus warranting further study).

As cannabis policy increasingly shifts towards legalization in most places around the world, I’m glad to see more scientific studies being performed on vaporization. The more information we have about the process, the better we can fine tune things to achieve the perfect balance of taste, vapor quality, and efficiency (which is especially important for medical patients). Recently, I’ve been happy using my vaporizers at 200-215C (depending on the vaporizer, cannabis strain, and the effects I’m looking to get). and hitting a bowl until I feel like its done (this has been working quite well for me so far!).