Most UK cannabis now ‘high potency’ 

Almost 95 per cent of cannabis seized by police in 2016 was of a high potency variety, according to a report from King’s College, London and GW Pharmaceuticals. Researchers analysed almost a thousand police seizures across the country and found that 94 per cent were of strong ‘skunk’ sinsemilla, compared to 85 per cent in 2008 and just over half in 2005.

Increase in potency is significent risk to mental health, says report’s author Marta Di Forti

The study, published in the Drug Testing and Analysis journal, found that the stronger varieties’ market dominance was the result of lack of availability of weaker cannabis resin, which could account for as little as 1 per cent of the product in the London area. While cannabis resin is usually rich in cannabidiol (CBD) – thought to help moderate some of the effects of the psychoactive component THC – this is often absent from sinsemilla. Stronger cannabis strains are thought to be a contributory factor to increasing first-time admissions for drug treatment, says the study.

‘In previous research we have shown that regular users of high-potency cannabis carry the highest risk for psychotic disorders, compared to those who have never used cannabis,’ said senior author Dr Marta Di Forti. ‘The increase of high-potency cannabis on the streets poses a significant threat to users’ mental health, and reduces their ability to choose more benign types.

‘More attention, effort and funding should be given to public education on the different types of street cannabis and their potential hazards,’ she continued. ‘Public education is the most powerful tool to succeed in primary prevention, as the work done on tobacco has proven.’

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