Despite the growing popularity of cannabidiol (CBD) products, there has been little research directly assessing whether the usage of high-CBD products can deliver positive results on urinary drug tests for THC. Now, however, researchers have found that patients who regularly use products containing CBD may test positive in urine tests screening for tetrahydrocannabinol (THC).
For the study, the researchers studied 14 participants at McLean Hospital in Belmont, Massachusetts, between June 201 8and February 2020. Each was instructed not to use any other cannabis/ cannabinoid-based product throughout the trial. All in all, the participants included 11 women and 12 white individuals.
The study period lasted for four weeks. During this time, each person administered a study product containing 1.04% CBD and 0.02% THC under their tongue three times per day for a targeted daily dose of around 30mg of CBD and just less than 1 mg of THC.
In the end, they found that after four weeks of daily dosage, 50% of the participants, or seven people, tested positive for THC from urine tests, while the other half tested negative. Gas chromatography-mass spectrometry tests then confirmed these results.
While interesting findings, the investigators say that further research is needed to confirm their results. In particular, they say that studies with larger sample sizes are necessary to assess which variables (ranging from product use to body mass index, age, race, and medication use) contribute to positive THC results. Also, given that the cannabinoid blend used in their study was 0.02% THC and that the upper THC limit for CBD products is 0.3%, further studies looking at results when higher quantities of THC are administered are also needed.
“It is often assumed individuals using hemp-derived products will test negative for THC.” write the researchers in their paper. "Current results indicate this may not be true, especially if assays are more sensitive than advertised, underscoring the potential for adverse consequences, including loss of employment and legal or treatment ramifications, despite the legality of hemp-derived products.”