With legal cannabis and hemp hitting the mainstream hard, and expanding rapidly across the U.S. and the rest of the world, the availability of products containing CBD in considerable proportions is exploding.
And, while some studies have suggested drug testing at work is a thing of the past, this is not the case for all jobs. Some jobs, as well as criminal justice and addiction treatment proceedings, among others, still require drug testing.
How We Drug-Test For Cannabis
During a recent conversation, postdoctoral fellow Tory Spindle, Ph.D., a researcher in the Behavioral Pharmacology Research Unit at the Johns Hopkins Bayview Medical Center, explained how we drug-test for cannabis.
“There is a need to understand whether the use of CBD products (…) can impact drug testing for cannabis given their growing availability and increased interest in CBD for therapeutic purposes.”
“Conventional urine drug testing for cannabis targets a common metabolite of THC called THCCOOH (THC is the primary psychoactive component of cannabis). Importantly, many CBD-dominant products contain low levels of THC, including hemp-derived CBD products which can legally contain up to 0.3% THC,” he said. “There is a need to understand whether the use of CBD products, with and without low levels of THC, can impact drug testing for cannabis given their growing availability and increased interest in CBD for therapeutic purposes.”
And this is what Johns Hopkins Medicine researchers set out to do in recent months, publishing their findings at the Journal of Analytical Toxicology this week.
A team at Johns Hopkins Medicine conducted a study in which six individuals administered pure CBD, both orally and using a vaporizer, as well as inhaled vaporized CBD-dominant cannabis (containing 0.39% THC) on separate occasions.
After dosing, they provided urine samples to determine whether they would test positive for cannabis using common drug testing standards.
“The results showed that pure CBD did not produce a positive result on a standard urine drug test for cannabis. However, 2 of 6 participants tested positive for cannabis after they inhaled CBD-dominant cannabis vapor,” Spindle explained.
In his and his colleagues’ opinion, these results have important implications for consumers of CBD products.
“2 of 6 participants tested positive for cannabis after they inhaled CBD-dominant cannabis vapor.”
“The cannabis used in this study was very similar in THC composition to what is found in legal CBD/hemp products,” Spindle continued. “Individuals who are subject to urine drug testing in their place of employment or elsewhere should understand that even very small amounts of THC in a CBD/hemp product can trigger a positive result for cannabis and that conventional drug tests cannot distinguish whether THC present in someone’s system came from cannabis, or a federally-legal hemp product.
“These results are especially important for people who use hemp/CBD products daily, such as for therapeutic reasons, because THC can potentially build up in a person’s system with repeated use, which could further increase the chances of a positive result for cannabis.”
Finally, Spindle pointed out the findings of the Johns Hopkins study are highlight the issue of some poorly regulated CBD products being advertised as “THC free,” even though they were found to contain levels of THC similar to (or higher) than the THC levels present in the cannabis used in a study conducted by Ryan Vandrey, Ph.D., associate professor of psychiatry and behavioral sciences at the Johns Hopkins University School of Medicine.
“THC can potentially build up in a person’s system with repeated use [of CBD products], which could further increase the chances of a positive result for cannabis.”
Vandrey and his collaborators at the University of Pennsylvania had published a JAMA study showing that that 21% of CBD/hemp products sold on the Internet contained THC, even though their labels didn’t properly disclose it.
“I have a hard time finding anyone who hasn’t used a CBD product at least once, but most are completely unaware of the possibility of THC exposure or a positive drug test as a result of using these newly legalized products,” Vandrey said in a release.