Increasing potency and price of cannabis in Europe, 2006‐2016 2019 Working Group Meeting for Statistics on Crime and Criminal Justice Teodora Groshkova 27-28 May 2019

…on behalf of University of Bath EMCDDA King’s College London Tom Freeman EMCDDA Teodora Groshkova Andrew Cunningham Roumen Sedefov Paul Griffiths King’s College London Michael Lynksey

Cannabis, THC, CBD THC (delta-9- tetrahydrocannabinol) Intoxicating Anxiety & psychotic symptoms Addiction CBD (cannabidiol) Non-intoxicating Anxiety & psychotic symptoms Addiction

Limited international literature …evidence of increasing potency in some drug markets for both herb and resin Quantify cannabis potency at European level Better understand health effects of cannabis Inform policy decisions for harm minimisation

Methods EMCDDA retail potency & price (unadjusted), 2006-16 Expected changes based on annual inflation from 2006 Harmonised Indices of Consumer Prices Adjusted outcome variables Changes in THC per € spent (value) Mixed effects linear regression models STROBE (strengthening the reporting of observational studies in epidemiology) statement

Trends in herbal cannabis  from 5-10% THC  from €7-12 per gram Similar dose of THC (mg) per € spent = expected change based on inflation (Eurostat)

Trends in cannabis resin  from 8-17% THC  from €8-12 per gram  from 11-16 mg THC per € spent = expected change based on inflation (Eurostat)

Strengths Quantify changes in potency, price and value Separate estimates for cannabis herb and resin in Europe; evidence for increases Internationally relevant information for policy & practice

…and limitations Possible sampling bias (police seizures and police surveys data) Data collection methods may vary Missing data CBD data not collected

Thank you