Cannabis being sold across Europe has DOUBLED in strength over the past 11 years, finds study
- THC concentrations have risen from five per cent in 2006 to 10 per cent in 2016
- Experts have for years warned of the dangers of using high potency cannabis
- Scientists drew on data from 28 EU member states, as well as Norway and Turkey
The strength of cannabis being sold in Europe has doubled over the past 11 years, according to the first study of its kind.
Concentrations of tetrahydrocannabinol (THC) – which causes the high – in herbal cannabis have risen from five per cent in 2006 to 10 per cent in 2016.
Experts have long warned of the dangers of high potency cannabis because of its established links to psychosis and mental health issues.
Concentrations of tetrahydrocannabinol (THC) in herbal cannabis have risen from five per cent in 2006 to 10 per cent in 2016
Scientists at Bath University drew on data collected from across 28 EU member states, as well as Norway and Turkey.
The findings, derived from figures from the European Monitoring Centre for Drugs and Drug Addiction, were published in the journal Addiction.
Concentration of cannabis resin – which typically also contains cannabidiol (CBD) – also jumped over the same time frame.
The research by Dr Tom Freeman and colleagues found THC content in resin went from eight per cent in 2006 to 17 per cent in 2017.
When present in cannabis, CBD may offset some of the harmful effects of THC such as paranoia and memory impairment.
However, new resin production techniques in Morocco and Europe have increased levels of THC but not CBD, researchers warned.
THE DIFFERENCES BETWEEN THC AND CBD
Tetrahydrocannabinol (THC) and cannabidiol (CBD) are both derived from the cannabis plant.
Together, they are part of the cannabinoid group of compounds found in hashish, hash oil, and most strains of marijuana.
THC is the psychoactive compound responsible for the euphoric, ‘high’ feeling often associated with marijuana.
THC interacts with CB1 receptors in the central nervous system and brain and creates the sensations of euphoria and anxiety.
CBD does not fit these receptors well, and actually decreases the effects of THC, and is not psychoactive.
CBD is thought to help reduce anxiety and inflammation.
Dr Freeman said: ‘CBD has the potential to make cannabis safer, without limiting the positive effects users seek.
‘What we are seeing in Europe is an increase in THC and either stable or decreasing levels of CBD, potentially making cannabis more harmful.
‘These changes in the illicit market are largely hidden from scientific investigation and are difficult to target by policy-makers.’
Dr Freeman added that an ‘alternative option’ could be to attempt to control THC and CBD content of herbal cannabis through regulation.
The study also revealed the prices of cannabis have risen over the same time frame.
Herbal cannabis has jumped from €7.36 (£6.61) per gram to €12.22 (£10.97) between 2006 and 2016. Resin now costs €12.27 (£11.02), up from €8.21 (£7.37).
It is estimated that around seven per cent per cent of European adults – in the region of 24 million people – have 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.
Recreational use is legalised in Canada and several US states, with medical use permitted in many more countries.
Skunk, the potent form of the drug, is responsible for a quarter of new cases of psychotic mental illness, KCL researchers announced two years ago.
They found skunk to be so powerful that users are three times more likely to suffer a psychotic episode than those who have never tried it.