8 Ways Corrupt Cannabis Labs Cheat The Numbers (and You)

I’ve written quite a bit about inconsistencies in THC potency results in the state of Oregon and the overall erosion of trust in cannabis testing because of it. I am working with a far more credentialed researcher to start to get to the bottom of the results that I received as part of a public records request. In the mean time, I thought it might be a good time to review the ways that I’ve heard that cannabis labs can inflate THC Potency, especially for flower.

In other words — this is a compilation of all the ways I’ve heard cannabis labs accuse each other of cheating.

Labs artificially inflate THC potency numbers because the cannabis industry has marketed THC so fiercely that consumers largely purchase product based on THC potency. After years of using the THC potency metric to describe psychoactivity of cannabis, THC potency has become the sole metric a majority of consumers look for when purchasing cannabis flower. In many cases, dispensaries claim consumers will not buy flower under 30%, and farmers claim they can not sell flower that does not meet certain potency thresholds.

Accusations in the industry point in all directions, especially as the recession hits the young, volatile cannabis market.

So — How Do They Do It?

Let’s say there IS a bad-actor cannabis farm out there that wants to sell as much weed as possible, and is willing to pay to make sure their potency result is a marketable one. How could the lab do that? AND — how could the lab do that and not get caught?

It ends up that there are quite a few ways, and they’ll result in varying percentage points added to potency. Here are the eight I heard the most when I’ve talked with labs.

1. Using Moisture % as a way to alter the number.

Moisture percentage can impact the THC potency of a sample, and moisture content or moisture percentage is one of the ways that labs are accused of cheating. The impact of this one is going to be pretty slight, but it could be meaningful enough to make the cannabis more viable in the current marketplace. On its own, it’s not going to result in something like the inconsistencies that are seen in Oregon.

2. Using a different calculation for loss on drying.

This is another trick of math that might bump a number a little bit, but not by much. There are two calculations for loss on drying:

(moisture loss) / (wet or starting weight)

(moisture loss) / (dry or ending weight)

These two calculations for loss on drying render slightly different results, and might be a way that labs change the numbers. Again, this will most often be a very subtle change.

3. Spike the sample.

There are a lot of ways to spike a sample of cannabis. This behavior ranges from kiefing the batch (which is legal in the state of Oregon for some inscrutable reason) to straight up spiking the sample with distillate or other methods. Each version of spiking a sample comes with a pretty good way of detecting it. For instance, using distillate used to be a popular way of increasing the potency of flower until it became easy to detect by looking at the ratio of delta-9 THC to THCA. The use of THCA isolates is also detectable.

Spiking samples to get higher potency values is a common and fast way to increase potency for selected results, especially if effective lab audits at the state level are not in place.

4. Sampling Cheats

While we’re talking about samples, let’s talk about sampling. Appropriate sampling procedures are supposed to ensure that the sample taken from a cannabis batch is representative of that batch. That doesn’t mean that appropriate sampling procedures are always followed. I’ve heard a variety of stories about this. I’ve heard several versions where a farmer handing a bribe and pre-prepared sample to lab samplers, and I’ve heard of farmers leaving the samplers with some kief and some time. While Oregon has recently updated its rules to include more specific information on sampling, it also increased the batch size to 50 pounds from 15.

5. Swap Samples With Known High Tester

If you’re going to be nefarious, you might as well go all the way and replace your sampled cannabis with a known high-tester. With some of the crazy machinations I’ve heard about labs doing, this method is both cheap and effective. Highly probable that this isn’t the method used to create the sort of mess we see in Oregon, but still effective enough to cheat.

6. Using a Standard Known To Give High Results.

A ‘cannabis testing standard’ is the material that is used to calibrate testing equipment. Many of the least dilute (therefore more effective) standards require DEA licensure (cannabis testing labs are federally illegal laboratories and not eligible for DEA licensure). The more dilute a standard, the more it can impact the results and can give much, much higher potency results. Some standards are known for yielding higher potency results, and some standard companies have failed to respond when clients have raised issues with standard accuracy. ORELAP gives no direction in evaluation of standard for use in testing, nor a list of approved manufacturers.

Unlike some of the other methods, using a standard would impact every test performed on that piece of equipment.

7. Calibration ‘Tricks’

Calibration is what it sounds like — calibrating the lab equipment to accurately reflect found amounts of THC. An intentional miscalibration of the machine would skew all of the results of the machine.

Most calibration ‘tricks’ would be caught during a thorough audit of the lab’s methods. There is no way, however, to address all of the possible tricks that could be used without a comprehensive audit of the entire preparation of the standard for calibration (there’s those standard issues we talked about again).

This is another method that would elevate the results for the laboratory as a whole.

8. Incorrectly Entering Sample Weight for Calculations

When incorrectly entered with the potency information, the sample weight is enough to wildly impact cannabis potency testing results. While the equipment used to record the mass must be calibrated daily, there is nothing to prevent someone recording a lower overall mass (which would push the potency up), and very few labs have the sort of equipment that interface this information with their lab information system, much less regulatory systems. This is an ‘easy’ cheat, as recording a mass around 10% lower than actual will yield roughly 10% inflation for potency.

What’s Happening In Oregon?

Several lab directors were willing to tell me off the record that most likely, the sort of numbers we are seeing in Oregon indicate a combination of using 6, 7, and 8. It is clear that Oregon’s cannabis lab market right now is a mess. Labs are closing due to the economic impact of the lack of oversight.

Since the scathing audit report in 2019, the laboratory situation in Oregon has only gotten worse. If Oregon has done anything to remediate the laboratory situation since the auditor’s report in 2019, it’s not visible in the data. The continued lack of oversight and meaningful audits has allowed for a few corrupt laboratories to run the honest laboratories out of business.

If you would like to learn more about my efforts to bring sanity and transparency to cannabis testing, please let me know in the comments!