Potency of Δ9–THC and Other Cannabinoids in Cannabis in England in 2005: Implications for Psychoactivity and Pharmacology
Gas chromatography was used to study the cannabinoid content (“potency”) of illicit cannabis seized by police in England in 2004/5. Of the four hundred and fifty two samples, indoor-grown unpollinated female cannabis (“sinsemilla”) was the most frequent form, followed by resin (hashish) and imported outdoor-grown herbal cannabis (marijuana). The content of the psychoactive cannabinoid Δ9-tetrahydrocannabinol (THC) varied widely. The median THC content of herbal cannabis and resin was 2.1% and 3.5%, respectively. The median 13.9% THC content of sinsemilla was significantly higher than that recorded in the UK in 1996/8. In sinsemilla and imported herbal cannabis, the content of the antipsychotic cannabinoid cannabidiol (CBD) was extremely low. In resin, however, the average CBD content exceeded that of THC, and the relative proportions of the two cannabinoids varied widely between samples. The increases in average THC content and relative popularity of sinsemilla cannabis, combined with the absence of the anti-psychotic cannabinoid CBD, suggest that the current trends in cannabis use pose an increasing risk to those users susceptible to the harmful psychological effects associated with high doses of THC.
Document Type: Research Article
Affiliations: 1: Department of Pharmacy, King’s College London, 150 Stamford Street, London SE1 9NH, United Kingdom. 2: GW Pharmaceuticals Ltd., Porton Down Science Park, Salisbury, Wiltshire SP4 0JQ, United Kingdom. 3: School of Pharmacy, University of Hertfordshire, College Lane, Hatfield, Hertfordshire AL10 9AB, United Kingdom.
Publication date: January 1, 2008