Consumers want to know two things about the chemistry of the bud they're about to smoke: does it have harmful impurities or biological contaminants, and how much of the various active agents does it have? The cannabis lab testing industry has sprung up partly in response to that consumer demand, and partly in response to pressure from regulators.

Lab testing of cannabis is a pretty new thing. Even though THC was first discovered back in the 1960's, it wasn't until a few years ago that cannabis testing became commonplace in California and other medically legal states.


Steep Hill Labs, in Oakland California, was the first to open in 2008, soon followed by CannLabs (Colorado) in 2010 and SC Labs and Halent Labs in 2011. Faced with an explosion of new products, including some highly potent and highly processed ones, regulatory agencies and consumers alike are turning to these specialized laboratories for information that will make their experiences safer and more enjoyable.

When cannabis testing first started the primary method was gas chromotography (GC), which heats up the material until chemicals vaporize and measures those vapors. This is not an accurate method of testing because the heat causes chemical changes to take place, namely the conversion of non-psychoactive THCa into psychoactive THC. As a result, GC tests artificially inflate the THC amount in samples; while this is good for anyone profiting from selling cannabis using inflated results, it is bad for consumers. These days most labs use either liquid chromotography (LC) or high performance liquid chromotography (HPLC), both of these methods do not involve heating the sample up and have much more accurate results than GC.

GC, LC, and HPLC tell you a lot more about a sample than just the amount of THC in it. Another cannabinoid commonly tested for is CBD, which is a non-psychoactive cannabinoid with a wide range of medical uses, including the treatment of pain, cancer, epilepsy, and dozens of other conditions. Cannabis is more than just THC and CBD; there are nearly seventy identified cannabinoids, as well as dozens of terpenes, and numerous other chemicals such as flavonoids and alkaloids. Terpenes are the flavor and scent chemicals that give everything in the world their own unique smell. The same terpenes that make lemons smell lemony and lavender smell so sweet are also in cannabis imparting those same odors and tastes. Research suggests that terpenes, like cannabinoids, have many health benefits. Limonene, is anti-inflammatory, said to reduce depression and anxiety, and may even have anti­-cancer properties. 

It is very important to know the potency of the bud you are smoking or the edibles you are eating, especially in the case of edibles which have been shown to be roughly ten times as potent as smoking bud. It is also highly important to know the cannabinoid and terpene profile because that gives you an idea of what the medical properties and flavor will be. For example, does it have lots of THC and myrcene, which can produce "couch lock" -- a highly sedated and overpowering high, or is it high in CBD which attenuates the psychoactive effects of THC but can be useful for neurological and psychological conditions? Knowing the entire cannabinoid and terpene profile can help you match your needs and desired effects with available strains.

It's also important to test for contaminants in bud like mold or pesticides. This is crucial for people who have compromised immune systems and should not ingest any mold spores. Lab testing isn't just for bud or edibles, it can be done to any cannabis sample and should be done to any cannabis concentrate that uses a chemical solvent, such as butane hash oil (BHO) or shatter. Chemical solvents commonly used include CO2, butane, propane, pentane, hexane, heptane, acetone, ethanol, and isopropyl alcohol. SC Labs uses a combination of testing styles to do residual solvent testing, including “Gas Chromatography/FID, Head-space analysis, and Mass Spectrometry.”

Most states with legalized cannabis do not have requirements that it be lab tested or grown without the use of harmful pesticides, putting the onus of testing onto medical cannabis collectives and the customers they serve. Oregon doesn't have any requirements for laboratory testing for pesticides and a recent independent analysis of hashes there found the presence of potentially carcinogenic compounds in the majority that were tested. Washington is one of the few states that has set a limit for residual solvents in chemical-extracted hashes at 500 parts per million, per gram. While the Washington testing requirement only applies to hashes, it is a start in the right direction towards requiring testing of all cannabis that is sold in stores.

Even in states with legal cannabis markets there are still healthy black markets with people selling cannabis the way they always did, out of backpacks and briefcases, from street corners and in bedrooms. The most advanced street dealers can have selections that rival some smaller legal dispensaries, with various strains of bud, hashes, pre-rolled joints, and even edibles. The one thing these dealers never have is recent lab results to show the potency and purity of what they have for sale. To really know what is in your cannabis then you need to go to a legal collective that lab tests their medicine for potency and purity.

All medicine, and even recreational alcohol, has to have potency results readily available on the package  in order to be legal for sale and use. The product must also conform to safety standards in the manufacturing practices.  This is to prevent any potential allergic reactions and to keep impurities out of the product.  Any legal cannabis market will need similar requirements of test results and proper safety standards in order to succeed and thrive in the long term.

 

Mitchell Colbert is a cannabis researcher and journalist who's writings have appeared in The Leaf Online, Cannabis Now Magazine, Weedist, AlterNet, and High Times Magazine.  You can follow Mitchell on Twitter.