University of Queensland researchers have studied the habits of recent recreational users to discover how much cannabis is typically used in a joint – and found significant variations.
The 31 participants, who had smoked cannabis in the last 30 days, were asked to roll joints, spliffs or to pack cones as they would normally do, only using oregano as a substitute.
The cohort produced three cannabis-only joints, three cannabis and tobacco spliffs, and three cannabis-only cones in that order. Only the modes of administration with which participants had previous experience were sampled – for example, those who did not smoke spliffs did not complete this part of the task.
The final sample sizes for each preparation were 30 for joints, 31 for cones and 25 for spliffs. There were significant variations across all three methods of consumption with joints ranging from 0.1g to 1.25g, spliffs from 0.12g to 1.21g and cones from 0.03 to 0.41g.
Those who used cannabis daily rolled three times the amount of ‘cannabis’ into a joint.
But while the team was unable to measure THC concentration directly using oregano, when they told participants to use the herb as if it was more potent, they did not adjust enough to adequately reflect the change.
The researchers said the majority of Australian research in this area has studied self-reported frequency of use and “crude quantification” – number of joints or cones smoked per day – as a proxy for cannabis exposure.
These metrics do not account for variations in the quantity or potency of cannabis and may poorly estimate the potential consequences of use, the researchers claimed.
They added: “The amount of cannabis used in common modes of administration may be highly variable. Daily use may be associated with using larger quantities of cannabis.
“The results indicate people may adjust the quantity of cannabis relative to the perceived potency… however, not proportional to THC concentration.
“The variability in quantities prepared shows that the THC exposure from one joint, cone or spliff varies based on individual differences in the preparation of these most common routes of administration.
“Importantly, it underscores the limitations of the current metrics of only asking participants to report the number of joints or cones smoked per day in standard Australian national surveys.”