Originally posted on Leafly.com
November 21, 2019
Author David Downs
Tens of millions of employees in all sorts of industries are encountering new questions when it comes to drug testing in the workplace
Workers who use a lot of CBD (cannabidiol) for pain, anxiety, insomnia, or a host of other symptoms, can accidentally (and unfairly) fail drug tests for cannabis in certain cases, media and experts report.
“We are aware of a few reports of CBD users who have flunked a drug test,” said Dale Gieringer, co-director of California NORML.
In the most common workplace drug screen—a urine test—employers aren’t looking for CBD, because CBD has never been found to impair judgment or motor skills. Instead, workers fail workplace drug testing for marijuana’s main active ingredient, THC, which can exist in low amounts in some CBD products and then persist in the human body for weeks.
A CBD product’s label might misstate the amount of THC, depending on the market in which you’re shopping. State-licensed adult-use and medical cannabis stores are regulated and mandate product testing, but outside of those systems, CBD product quality can vary in a largely unregulated market. Tests of CBD products from unlicensed stores have come back positive for THC.
“It’s caveat emptor,” said Barry Sample, Ph.D., senior director of science and technology for employer solutions at the nation’s biggest drug testing company, Quest Diagnostics. “The real issue is, how do you trust the labeling?”
Furthermore, if you consume enough CBD—on the order of 1,000 milligrams a day of CBD—just the residual THC could put your test results in the danger zone. This is a big deal because a failed drug test can result in the denial of loss of both job and income, and can also lead individuals to lose access to important resources like education and welfare benefits, child custody, and prescriptions for pain medication.
Can you fail a drug test for CBD? Not really, but sort of
You won’t fail a drug test for CBD, but you could potentially fail a drug test for any residual THC in that CBD product.
Sample said Quest Diagnostics does not test for CBD. THC, however, is on the lengthy list of drugs they test for.
Here’s how drug tests work. Employers collect and send off samples—largely urine—to drug testing companies who run them through a machine that can measure trace chemicals in the liquid. Technicians look for evidence of a byproduct of THC, the main active cannabinoid in cannabis. (More rarely, employers may test saliva, hair, or blood from their employees. We’ll get to that in a minute.)
One key guideline is drug-testing rules for federal employees. A federal worker will fail a drug test if their urine tests positive for any more than a trace amount of the THC metabolite (THC-COOH). And by “trace,” we mean just 50 billionths of a gram per milliliter of urine (50 ng/ml).
THC is the most common reason a worker fails a drug test. Some 2.3% of all US drug tests came back positive for cannabis use in 2018.
Watch out for old tech
There’s also the potential that an older, not uncommon type of analytical method falsely identifies THC in a sample that only contains CBD. That method is gas-chromatography mass-spectrometry with the derivatization agent trifluoroacetic anhydride (TFAA). Tens of thousands of false positives might stem from the error annually, reporter Amanda Chicago-Lewis estimates, but at least there is some recourse—CBD users have successfully challenged a failed drug test for THC if the lab used this specific method, which can result in a false report of CBD as THC.
Why is there THC in my CBD oil?
The cannabis plant produces both THC and CBD. Medical cannabis and industrial hemp are cousins—both create dozens of similar compounds called cannabinoids.
So CBD from “federally legal” hemp can still consist of up to 0.3% THC. If you ingest very high doses of CBD—in the thousands of milligrams per day—from federally legal hemp oil, that means you may also be ingesting at least 1 mg of THC as well.
“If you’re liberal with your hemp CBD oil use, you could hypothetically test positive for THC,” said Greg Gerdeman, Ph.D., chief science officer at Colorado’s United Cannabis, makers of Prana Hemp and Prana Medicinals.