According to a new study, the frequent smoking of CBD-rich cannabis (that has only trace amounts of THC) can trigger a positive urine test for carboxy-THC, thus leading to a failed drug test.
Researchers assessed a subject who inhaled one CBD-rich joint per day (6% CBD and 0.2% THC) over a 26-day timeframe, and by the 15th day the subject’s urine sample showed the presence of carboxy-THC above 15ng/ml levels, NORML reported.
In contrast, the subject’s hair sample and oral fluid both tested negative for the presence of carboxy-THC and THC.
“[T]his study based on a single subject suggests that the repeated exposure to CBD-rich cannabis (containing small amounts of THC) can generate positive results when biological samples are tested,” the authors concluded. “In particular, positive urine results for THC-COOH, using the confirmatory cut-off of 15 ng/mL, were obtained after a 15-days period of consumption. These results show the potential risk for chronic CBD-rich cannabis users of failing a urine drug test.”
A previous study saw similar findings, where the consumption of hemp CBD products (that contained no more than 0.3% THC) triggered a positive urine test for marijuana.