Is Cannabis Lab Testing A Scam

Rambo July 21, 2013 25
Is Cannabis Lab Testing A Scam

A few weeks ago I was waiting in the lounge of a cannabis dispensary and overheard a rather heated discussion about cannabis lab testing. One customer swore that it was a scam, and that dispensaries only advertised lab results as a marketing gimmick to legitimize outrageous prices. The other customer swore, “I’m not smoking no poison, I’d never buy weed that hasn’t been lab tested first.” While neither of the gentlemen were particularly well-informed about the subject, both arguments did have some merit, as well as some serious flaws.

The past decade has been a gold rush for the medical cannabis industry. Thousands have seen the opportunity to make a quick dollar and have jumped into an industry they hardly understand. Many would-be growers have no prior horticultural experience, and are ignorant of the risks associated with improperly grown cannabis. Others have no qualms about using dangerous chemicals and taking unethical shortcuts to produce their products. To make matters worse, many dispensary owners don’t understand the industry any better.

The market is flooded with cannabis that may appear to be high quality but in fact is coated in poisonous pesticides, fungicides, and plant growth regulator–or thriving with colonies of dangerous microbes–or both. While many cannabis users may not notice any ill effect in the short term, some medical cannabis users are seriously ill and highly susceptible to poisons, irritants, and microbes. These are the same patients who are not in a position to grow their own medicine and rely on dispensaries.

Every medicinal, pharmaceutical, food or drink producer is required to provide third-party testing to verify product safety. Unfortunately, there is no basic level of safety or quality required for medical cannabis or the medicinal products made from cannabis. While a few municipalities require dispensaries to have their products lab-tested, this is far from the norm.

As the industry has matured, many growers and dispensaries have begun to lab test their cannabis products for the safety of their patients, and/or to give them a competitive edge. As the demand has grown for these services, labs specializing in cannabis testing have sprung up like little ganja plants, to meet the needs of the market. Most medical marijuana states now have at least one laboratory that can perform basic tests. This has empowered dispensaries to test their products for both safety and and potency, which better enables patients to choose cannabis best suited for their symptoms.

Cannabis Testing Is A Good Thing, Right?

What’s with that scary word “scam” in the title? Back to my story of the two gentlemen arguing in the dispensary. As I listened to them argue I looked around and read the big sign above the counter that stated “All medicine has been lab tested.” What did that mean exactly? All of the samples behind the counter and on the menu had the THC levels advertised, so I had a pretty good idea they were at least doing basic potency testing.

I asked the three clerks behind the counter what other testing was performed. As expected, I got three completely different answers. One said that they tested for everything, the other said they tested for mold and THC. The last told me they didn’t test for mold anymore because it was too expensive and they only bought from reliable growers anyway. He also mentioned that it was all organic so we didn’t need to worry about pesticides. This was pretty much the response I expected. It’s not uncommon for people who work in an industry to know very little about it. It’s just a job, right?

The Low Cost of Testing Cannabis

What’s sad here is not how little they knew, but that for this particular dispensary, potency was a higher priority than safety. Lets look at the math and see how much money they saved by not testing for the safety of their product. For this example I am going to use retail customer prices available from our friends at SC labs. Potency testing runs $80 while testing for potency combined with pesticides, plant growth regulators, fungicides and microbes costs about $168. Most labs require only a one gram sample for testing and most dispensaries will only test one sample from any given batch of cannabis. This means if a dispensary buys one pound from a grower or vendor and sells it in ⅛ ounce (3.5 gram) increments for about $50 each, the dispensary would spend only 68 cents per sale for a complete test.

If this pisses you off, just wait. Dispensaries often buy more than one pound of the same cannabis at a time, sometimes 10 pounds or more. If the dispensary only payed to have one sample tested the cost per ⅛ ounce could be divided  by 10, now costing the dispensary only about 7 cents per sale. On top of this, SC labs as well other labs, offer significantly reduced prices for accounts that do a high volume of business with the lab. You and I might not qualify for these savings, but dispensaries will. In many cases this could nearly cut the cost of testing in half again. Don’t ever let a dispensary tell you they can’t afford to do full lab testing on their medicine. It costs about the same to test  the cannabis as the packaging your medicine came in.

Price List of SC Labs Testing Services

  • Potency –  $80 (Cannabinoids)

  • Microbial – $50 (Mold, Mildew, E Coli etc)

  • Pesticides, Plant Growth Regulators, and Fungicides- $50

  • All 3 of the above tests  $180

  • Residual Solvents $100 (for extracts like BHO or Wax)

The Accuracy of Cannabis Potency Testing

Lets move on to potency testing, since that seems to be where most dispensaries are putting their money. How important is it to know the exact THC content of the cannabis you’re smoking? Some would argue it’s pretty darn important. Hey, you’re spending your hard earned money. You want to know you’re getting high quality medicine, right? Why would you buy an ⅛ that tests at 18% THC, when for the same price you could buy an ⅛ that looks and smells just as good and test at 20% THC?

I’m not going to tell you that cannabis potency testing is worthless but I will suggest it may not be as important or as accurate as you think. While the accuracy of test itself is probably spot on, no two buds off of the same plant are going to test exactly alike. I haven’t done an experiment myself, but based on a conversation with Ian at SC Labs, there is often as much as a 10% variation in the THC levels of multiple buds from the same plant. This means that even though the sample tested came back at 20%, the ⅛ you purchased could really be at 18% or it could be at 22% THC.

To complicated matters a bit more, the pound of buds that the sample came from probably contains buds from multiple plants. Hopefully they are from the same strain but that’s not guaranteed either. Harvest can be a busy and often confusing time. Growers rarely grow only one kind of plant. Mistakes happen. Expect a pound will have buds from multiple plants and possibly different phenotypes as well. Here is another monkey wrench to scramble your brain, the lab results can be skewed simply by how dry the bud is. Yes, I said it, the water content of the cannabis sample that is tested will affect the level of cannabinoids in the lab results.

Not All Lab Testing Is Equal

There are two primary methods for testing the cannabinoid potency of a cannabis sample. The first is Gas Chromotography which requires that the cannabinoids be vaporized so the gasses released can be analyzed. The downside of this method is that it does not differentiate between THCA and THC or any of the other cannabinoids in acid forms. This may not be important for some patients but makes it impossible to test for decarboxylation levels which are important for lab testing edibles.

The most accurate method for testing cannabis potency is with High Performance Liquid Chromatography. This method allows the testing facility to accurately read the levels of both THCA and THC as well as other cannabinoids in both of their forms. Considering the reasonable price of this equipment, any reputable facility testing cannabis potency should be using High Performance Liquid Chromatography.

Microbiological Contamination Testing

Unfortunately fungus and bacteria thrive in the same environments as cannabis. Anyone with much experience growing cannabis can tell you how common mold and mildew problems can be. Real-Time Polymerase Chain-Reaction (PCR) technology allows cannabis testing facilities to quickly and accurately determine the levels of potentially dangerous fungal contaminant such as Scopulariopsis, Rhizopus along with the more easily seen Botrytis and Powdery Mildew. Most cannabis growers and users wouldn’t guess that bacteria such as Listeria, E Coli are commonly discovered in the cannabis that dispensaries send for lab testing. Luckily these can all be detected through PCR testing. Pathogens like these may cause symptoms like food poisoning in healthy individuals but can be deadly for patients with compromised immune systems.

Pesticides, PGR’s and Fungicides

Most cannabis growers have very little experience with traditional horticulture and are usually  ignorant of the proper and safe use of pesticides and fungicides. All too often poisons meant only for ornamental crops are used on cannabis. To make matters worse, dangerous and often banned substances like plant growth regulators are marketed directly to unknowing cannabis cultivators. Even pesticides and fungicides labeled as safe for food crops are meant to be applied to fruit and vegetables that can be washed before consumption. Cannabis is rarely washed before it is smoked.

We should also consider the potential chemical changes that might occur in a pesticide or fungicide when it is smoked and inhaled with the cannabis. I would wager that the majority of safety testing for pesticides is for crops that will be eaten and not smoked. Liquid Chromatography and Mass Spectrometry testing can detect dozens of these commonly used pesticide even when present in trace amounts.

Less Common But Equally Important

Residual Solvents – Cannabis Concentrates

The popularity of smoking or vaporizing hash oil, wax, budder, shatter and other forms of chemically concentrated cannabis is rapidly increasing. With this rise in popularity, amateurs are beginning to make their own extracts and develop new cheap methods for performing the extractions. All of the methods require a solvent. Some state of the art systems use high pressure CO2 but most use potentially dangerous substances like butane, ethanol, propane and a number of other petroleum or alcohol based solvents. Residual Solvent testing allows dispensaries to guarantee that their cannabis concentrates are free of chemical solvents or impurities and safe for their patients.

Terpene Analysis

Terpenes are organic compounds in the plant that create the odors that make each bud unique. Not only do they contribute to the enjoyment of smoking, but they have an impact on the medicinal and physiological effect. While still a relatively new service, some cannabis testing labs are beginning to test for terpene levels. As we begin to learn about the synergistic effect of terpenes and cannabinoids, pointless questions like “is it Indica or Sativa?” could soon be a thing of the past. This is a potential game changer for medicinal patients who struggle to find strains that work for their symptoms.

Edible Testing

Very rarely do I see lab testing done on edibles. While popular brands like Cheeba Chews test their own products and advertise potency on the label, many dispensaries make their own products and don’t really know the exact potency of their edibles. There is a little math required to convert the lab results on edibles to something intelligible to consumers, but it can and should be done. If for no other reason than patients need to know the potency of the edible they are consuming.

So, Is Cannabis Lab Testing A Scam?

If the only test a dispensary has done is the cannabinoid profiles, then yes, I would argue it is more of a marketing ploy than anything else. Cannabinoid ratios on their own, probably won’t help a customer make an educated guess as to what will work for them and it certainly won’t keep them safe from contaminated medicine.

I might be beating a dead horse, but I sincerely believe it is the responsibility of every dispensary to guarantee all the medicine they provide is safe for their patients. There are no established standards for the cannabis industry. This is the wild west. Cannabis dispensaries, growers, and cannabis testing facilities need to work together. Not only will patient benefit from reliable access to safe medicine, but the medicinal cannabis movement as a whole, might actually earn some of the legitimacy it has been struggling for.

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  1. drblue July 22, 2013 at 4:37 pm -

    Thanks again for another useful article. You’re the only one I’ve found on the internet who’s done some real research on decarboxylation methods. Any progress on testing extraction rates for hot and/or cold tinctures or extractions in alcohol vs. fats? There is so much information out there. It seems extraction is much better in fat or oil but I’m sure the length of time it’s given will make a difference. Any advice?

    • Rambo July 22, 2013 at 11:18 pm -

      I’m actually pretty curious about this myself. I honestly don’t know the answer. I will get around to this eventually.

  2. 45yrtoker July 22, 2013 at 11:15 pm -

    Just a comment about Rambo’s statement that most pesticides are tested on food crops, not smokables. Very true, but in the southern states, some folks are taking things a bit further. Some years ago, I was seeking a pesticide for leaf hoppers that was systemic. I found Imidacloprid, and I also found that it is registered for use on tobacco in tobacco producing states.

    I was very excited to find that this had been tested on a smoked product, so I purchased some. But, what I purchased was registered for use in California, and tobacco wasn’t on the label. I also noted that it contained the active ingredient at a different percentage than the products manufactured for the tobacco states. So, as I was about to mix it for my 1st application, I went on line to look at the tobacco label again and do the math necessary to determine how much of the product I should be using.

    While looking over the search results for the tobacco states’ label, I noticed something from a southern university (University of Tennessee, I think) about the chemical being lab tested, so I went to that site to see what it had to say.

    Turns out that they grew some tobacco and treated it with Imidacloprid during it’s growth. Then, they harvested it and smoked it out in the lab, testing both the direct and the side chain smoke for the chemical. It was found present & intact in both! So, Rambo’s point is a good one, and you should never assume that just because a product is labeled and approved by the state for use on food crops, that it’s actually safe, even on them! And, the last people you should EVER listen to are the salespersons in ‘grow’ stores.

    Only this afternoon, a friend called me to say that he’d been to both of the stores in Stockton, CA, and that they had both recommended Avid for mites and had it available for sale. He said, “Isn’t that one you said not to use? They say it’s OK, as long as you use it only before bloom.” Avid is only approved for use on ornamentals and has never been tested on anything smokable, at least not that I can find. This just point too how little people care about your health when there’s a dollar to be made. Be cautious, do your research on the web and only listen to experts – professionals, not your friends (yes, their intentions are good, but are they professionals) or your hydro salesperson!

    I’ve been a commercial walnut producer for 30 years, and I have a California Pest Control Advisor at my disposal. I still do my own research before I trust a product. Check out Safer’s new EndALL. It may cause some phytotoxic white spotting (which is mostly cosmetic), but it works on nearly every insect, including mites and their eggs, and is safe. Test spray a couple of leaves first. Some varieties don’t mind it, and it’s harder on young clones and seedlings. It contains Potassium Salts of Fatty Acids (the ingredient in Safer Insecticidal Soap), Clarified Hydrophobic Extract of Neem Oil and Pyrethrin, all safe organic ingredients.

    • bongstar420 April 12, 2014 at 3:09 pm -

      The “approval” just means the likely exposure levels are unlikely to cause a measurable outcome for the individual. It does not mean that it is completely safe for everyone, everywhere. The same is true for organic pesticides. Just because a chemical was synthesized by a plants does not make it safer than otherwise. The “approval” standards for organic pesticides are exactly the same and are evaluated by the same people as far as GAS goes.

      I’d probably stay away in Imidachloprid in general but I’d stick with never for medical stuff, and that is especially true if it is for really sick people. I would imagine that a Cannabis plant would have to grow for quite a while (at least several months) after a single Imidachloprid application to test negative for any residue.

  3. Rob August 13, 2013 at 10:18 am -

    Very well written article. Looks like you get it and you’re right, potency is just one part of the equation. It is after all, about safe meds!

  4. Chronic Relief January 4, 2014 at 1:33 pm -

    Excellent article! And, great comments. I am currently writing a guide book to cannabis for the terminally and chronically ill. Right now, I am putting the finishing touches on the book beefing up the testing section. Your article is in alignment with what I have heard from folks I’ve interviewed.

    Are you willing to visit with me further off-line about this issue?

    Regardless, you have raised awareness on an important topic. When I first started this project I was super gung ho about testing. While I am still an advocate for testing, I find that the more I learn the more conditional my advocacy becomes.

    Lastly, thanks for outlining the economics for testing. That will really help people truly discern which dispensaries are motivated to help people and which ones are greedy. Don’t get me wrong here. I love making money and believe in everyone’s right to be prosperous. For me, helping people and prosperity are not mutually exclusive. Well done!

  5. Steve January 13, 2014 at 8:56 am -


    Can you tell me what labs you found that use real time PCR for microbial testing? I haven’t been able to find one. Thanks!

  6. Jim February 11, 2014 at 3:14 pm -

    Steve, Check out Forensic Analytical Labs in Hayward, CA they use qPCR for the detection and quantification of Molds in air and on solids.

  7. Joseph Archuletta February 12, 2014 at 7:34 am -

    I have had cancer for 6 years now and have been testing and experimenting with different extractions. I have a mini lab and with my wet/dry process I can mix up some ratios where the strain is no longer relevant. Soon we will have ailment specific ratios in a regular daily dosage. I have healed so much during my research. Anyone in Az wishing to collaborate? Trimforthecure.

    • Robert May 11, 2014 at 6:03 am -

      I am definitely interested in your research on ailment specific ratios. Feel free to email me. I am in Arizona also.

  8. mona February 26, 2014 at 6:01 pm -

    Please remember that there are ways of dealing with pests that will not affect the plant at all, a small percentage of alcohol, will kill everything from , microbes, and pathogens, and all you have to do is flush the plant with fresh water for the last two weeks of bud development it also will leave such an amazing taste to the buds, baking soda diluted is amazing for fungus I used it all the time in my garden and it is safe since it also will wash away with a light mist of water. it is important to remember that the last two weeks of growth should be a clean growth time to flush any nutrients or fertilizers even if fully organic

  9. sunseeker47 March 4, 2014 at 3:19 pm -

    If you do a little more research you will see that HPTLC testing is the best for botanical substances way before these machines were put to use this type of testing has always been the best and by far the easiest and cheapest
    Independent research comparison of the 3 types of testing and a video plus information on all testing methods visit
    Correct information makes us all more aware and in the long run will give a standardized way of testing which is not currently available. Do your research be aware

  10. Budmaster1 March 13, 2014 at 3:36 am -

    I thought the piece above was a awesome informative and well written subject that needs to be told. I don’t care what company a person uses but its cheap enough and if your a grower wouldn’t you want to know just how good your stuff is coming out. We pay good prices for seeds and I would want to see if my plants are reaching full potential as advertised, so for now on since its cheap enough I will get every grow tested if for nothing else, to see if my growing skills are as good as I think they are.

  11. Budmaster1 March 13, 2014 at 3:37 am -

    GOOD JOB>>>>>>>

  12. bongstar420 April 12, 2014 at 2:34 pm -

    The potency testing varies by %20, so you could say it is %80 accurate. It is good enough because what we are talking about here for instance is %20 THC +/- %2. The comment about variation over the plant is generally accurate and it will vary a further %20. The price scheme should be three tiered for groups like %5-10, %11-20, and %21-30. I’d say you could include terpenes analysis in there, but a lot of those terpenes are dirt cheap from other plant sources, so I cannot see how anyone could use that to justify different prices in a competitive way.

    The commenting about costs is not different from any other business complaining about the cost of labeling (because it is a labeling issue). It is not really the cost, but the fact that they do not want you to find out you can buy Linalool for a 100 times cheaper by getting Lavender oil instead of Lavender buds.

    The organic thing. People just want an easy way to think they are being healthy. What people generally do not know is that organic food is not beneficial over conventional food in statistical terms (people who eat strictly organic diets do not get less cancer for example). Organic products can be just as dangerous to the consumer an synthetic ones depending on the individual. In fact, I would bet a pretty penny that a lot of organic Cannabis would look pretty bad vs some non-organic stuff if you were to give it a heavy metal analysis for things like Cadmium, Lead, Arsenic, and Mercury.

    The problem with all of this is that if we require it (by laws) here, we have to require it everywhere on everything. I should have the right to know what all ingredients are and what all possible contaminants are. That’s a better way to effect the outcome of product standards.

  13. BC95124 May 22, 2014 at 2:43 pm -

    Is anyone developing a retail level testing system so incoming product can be tested by the dispensary and so the actual buyer can see a test being run right at the counter? I assume that the first test for this would be potency. If this is happening what does it look like and if not why not?

  14. Tonia Bibbs May 28, 2014 at 1:49 pm -

    Rambo – Thank you for the article. Definitely one of the best I’ve seen.

  15. James June 20, 2014 at 9:38 pm -

    One of the most accurate articles I’ve read on testing. You also have to implement a 3rd party QAS for the lab. This should be run just as any pharmaceutical or nutraceutical testing. You can do it in house but need your equipment calibrated on a consistent basis. One can operate under an ISO system and the cannabis standard that is going around the activist sites is a revenue generator for ASA et al. Just plug into what works, ISO has been around and covers all the ground work.

  16. Reds2Cents June 20, 2014 at 10:05 pm -

    How did the customers argument that “I’m not smoking no poison, I’d never buy weed that hasn’t been lab tested first.” have any merit? His comment has no bearing on whether or not the Lab or the Dispensary is “making up” their potency numbers. Of course if they were, then he would be a (as if not one by others definition of the word) poison smoker! Yet to know for sure purchase a $55,000 testing machine and have several companies test the same strain you do and check each results to know if you got screwed by Lab testing cause you sure did when you bought the $55,000 machine to justify your complaint over $50

  17. sunseeker47 June 25, 2014 at 3:12 pm -

    The test kits at: have been working fine, tinctures and glycerin’s have been testing with no problems a few small adjustments depending on the mix you are using. Here is a link to a food testing kit that test for many popular pesticides.

    Any microscope over 40X magnification will show mold, There are some great ones 80-120x magnification with built in camera so you can put it on your computer monitor and save it as a jpeg on for around $80-$140.00
    Regardless of what some people say you can put together a nice little lab that test most marijuana substances with as much accuracy as any large lab for very little money just do your research.

  18. Lex Kenneth July 3, 2014 at 10:25 pm -

    I am SO glad to read this article. In the WASTED land of internet weed consumers, and dispensaries, the discussions and information are *almost entirely* hogwash (consumers) and outright lies (dispensaries). Some might consider that harsh, but I’ve been dilligently querrying dispensaries here in Coorado for four years…as well as a few labs, and my god, I simply can’t believe the almost total lack of integrity in this business, top to bottom. And to my surprise…it’s getting worse. Among ALL the 20 or so dispensaries I;ve contacted in Denver, Colorado Springs & Pueblo, “Lab Testing” is not done at all, as far as I can verify…because each clerk/ hack/ bud-tender tells me some mish-mash gobedly-gook story (changes EVERY TIME) that the testing is not of any specific batxh , but was maybe done once, or once in a while, or blah blah…they’re making it up, or else just agreeing with the out I give them to save face. They’re all so high, they raely display any critical thought, and to a person, resort to “Indica vs Sativa” nonsense. The fallacies inherent in that comparison are so many as to be stupidly funny. Anyway, I can NOT EVER find a dispensary that has thc/ cbd test data on any product actually on hand. I have yet to meet ONE single person in ANY dispensary that had any scientific knowledge, or even a rational mind, and I really mean that. They all get annoyed at having to answer questions that require any empirical data, especially while being so high. They are just pimps and hos.
    PLEASE…somebody prove me wrong…is there a place in Colorado (besides the Stanley Bros) Realm of caring, where I can go in, and find, say a 3-4% THC strain with at least as much CBD, so I can make edibles/ tinctures that make me feel GOOD, and relieve my constant pain, with a mild euphoria? Because any discussion of particulars (accepting the average weed in dope houses is like 20% THC/ .05 % Cbd, is like talking to a brick wall.
    Any ideas, anyone? I am so hoping to stop using benzos for muscle relaxation, and stop hydrocodone for pain…no addiction problems at all, and I am still an athlete, so I’ve no patience for being an addict or a wasteoid… but, you know, years of beating my head against the wall of lies and stupidity in the dispensary racket makes me feel like big pharma is in fact MORE HONEST. Imagine that. Ideas, please???

  19. Lex Kenneth July 3, 2014 at 11:12 pm -

    Really, I can’t believe the gaul these dispensary pushers have…the bald-faced, make-it up-as they go along yarns they spin about THC / CBD in a product, then having no current data on a product they “recommend,” falling back on “well, everybody reacts differently,” if pushed. Of course it’s not medicine, it’s hard drugs. for perfectly healthy men in their early 20s, buying jet fuel from skanky little girls. Imagine going into a pharmacy and getting your Lyrica…the pharm tech hands you a bag and you say 250 mg caps, right? They say “um, could be, it …um, varies…take more or less.” Christ I hate these jerks. There HAS to be one honest dispensary in this state…for God’s sake, it’s everywhere…didn’t ANYONE figure there was a market for real medicine?

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