The detection of cannabinoids in breath after ingestion of cannabis-infused edibles.

The increase of Δ9-tetrahydrocannabinol (THC) in breath after cannabis inhalation has been well-documented in the forensic field, but the trends after ingestion of cannabis-infused edibles have not yet been investigated. In this study, participants ingested a cannabis-infused edible and provided breath samples before and at three timepoints after ingestion. Participants were assigned to one of two breath sampling devices. THC was found in most pre-use breath samples and THC concentration had variable trends after ingestion. Nineteen participants exhibited a maximum in their THC concentration at 47 min, 92 min, or 180 min after ingestion, while six participants had their highest THC concentration before the observed ingestion and four participants had no significant change in THC concentration over the four samples. Five additional cannabinoids were detected in breath. While cannabidiol (CBD) trends followed THC trends for some participants, diverging trends in other participants suggest different biological processing of CBD derived from edibles. This proof-of-concept study shows that THC concentration in breath can increase after the ingestion of cannabis-infused edibles, but the uncertainty of breath measurements and a longer time window need to be further explored.