Concentration of tetrahidrocannabinol in joints

Purpose This study aims to assess the potency and dose of Δ-9-Tetrahidrocannabinol (THC) and Cannabidiol (CBD) in cannabis joints. This will enable better estimates of the degree of exposure in a user and contribute towards a better understanding of potential harmful effects. Design/methodology/approach Analysis of intact joints confiscated by law enforcement on the street in the autonomous region of Castilla y León (Spain) during the years 2017–2019. Findings This study analysed THC, CBN and CBD in marijuana joints (N = 744). Joints contain cannabis and tobacco (N = 729), had a median net weight 0.69 g (IQR = 0.28); concentration THC median was 6.30%(IQR = 4.51) and THC median dose 42 mg (IQR = 32.75). A total of 35.5% mixed joints contained CBN – median percentage 0.61% (IQR = 0.51). CBD was detected 10.3% of mixed joints – median percentage 0.13% (IQR = 0.12) and median dose 1 mg (IQR = 0.92). CBD/THC ratio presented median value of 0.02 (IQR = 0.02). The samples analysed comprised pure cannabis joints (N = 15), with THC median 11.86% (IWR = 6.30) or median dose of 118 mg. Originality/value The study found high values for concentration and dose of THC and CBD in cannabis joints, warning of high exposures for the user and associated potential consequences. The results obtained contribute new perspectives on the definition of a standard cannabis unit.