By Emily Ledger
Both the prevalence and the strength of illicit cannabis products have been reported to be on the rise over the last few decades. Now, a recent report has revealed that the levels of THC in some street cannabis products has increased by almost 25%.
The international study, carried out by researchers from the Addiction and Mental Health Group at the University of Bath, analysed over 80,000 illicit street cannabis samples that have been tested over the last five ecades in the UK, USA, the Netherlands, France, Denmark, Italy, and New Zealand.
Samples included herbal cannabis, often called flower or bud, as well as other cannabis products such as extracts and resins. The findings of this research was recently published in the journal Addiction.
It was revealed that THC – the dominant cannabinoid in cannabis plants known for its intoxicating, ‘high’-inducing properties – levels have been consistently on the rise over the last50 years.
While THC concentrations detected in herbal cannabis saw an increase of around 14% between 1970 and 2017, cannabis resin THC levels increased by 24% between 1975 and 2017. The researchers report that this increase is equivalent to around 5mg THC per year. It is also noted that one 5mg dose is enough to cause mild intoxication.
It is believed that the increase in THC levels in illicit cannabis products can be traced to the developing availability and market share of a number of stronger varieties and strains of the plant.
Increasing THC levels have led many researchers, politicians, and drug reform advocates to call for the better harm-reduction strategies. These include a health-led approach to cannabis consumption, in replacement of prohibtion.
Some see the need for standard units and labelling and guidelines for safer consumption, similar to those available for alcohol. Furthermore, others see the opportunity for drug policy reforms such as decriminalisation and even legalisation.
Advocates argue that prohibition and the criminalisation of cannabis users has had a negative effect on public health while having no bearing on cannabis use. Cannabis remains the most used illicit drug in the world, with more Europeans entering drug treatment for use of the drug than for heroin or cocaine.