Since 1993, THC potency in cannabis has increased from 3.5% to 12.3%. Researchers report those who first used cannabis in the early 90s had a 1.88% increased risk of developing cannabis use disorder, while those who started on higher potency THC marijuana are at a 4.85% increased risk.
A new study reveals the potency of THC in both herbal cannabis and cannabis resin has increased significantly in Europe since 2006.