It is estimated that 7.2% of European adults – 24 million people – used cannabis in the past year.
Across the world, 192 million people use the drug in a variety of markets ranging from heavily sanctioned prohibition to commercialised legal sale.
Cannabis resin and herbal cannabis have significantly increased in potency and price, according to the first study to track changes in the drug across Europe.
The research, published in the journal Addiction, drew on data collected from across 28 EU member states as well as Norway and Turkey, for the European Monitoring Centre for Drugs and Drug Addiction.
It found that over the past 11 years, cannabis potency has doubled across Europe.
Concentrations of delta-9-tetrahydrocannabinol or THC – the main psychoactive constituent of cannabis – in herbal cannabis increased from 5% in 2006 to 10% in 2016.
For cannabis resin, THC concentration rose from 8% in 2006 to 10% in 2011, but jumped to 17% by 2017.
The price of herbal cannabis increased from 7.36 euro per gram to 12.22 euro between 2006 and 2016, while cannabis resin rose from 8.21 euro per gram to 12.27 euro over the same period.
Press Association via Irish Examiner