The characteristics of cannabis in Australia

NDARC Staff

Wendy Swift (NDARC) and Paul Dillon (NCPIC)

Other Investigators

Steve Allsop (National Drug Research Institute) and Colin Priddis (Chemistry Centre of Western Australia)

Rationale

There is little detailed information about the Australian cannabis market, including the chemical characteristics of the locally available cannabis product. The collection of accurate and current data is crucial for providing appropriate, evidence-based information to the Australian public, to cannabis users and their families, and to health, law-enforcement and other related practitioners. The study builds on recently completed pilot work on cannabis potency and contamination.

Aims

This study aims to establish a methodology to assess the characteristics of the locally available cannabis product, and to use this methodology to collect information on cannabis seizures in Western Australia.

Design and Method

Chemical analyses of cannabis seizures will be informed by a recent pilot project comprising a literature review - McLaren et al (2008), Addiction - and interviews with an international group of key experts on potency and contamination. This research has identified substantial variability in cannabis potency but an overall trend towards a modest increase in the US and some European countries. It has also identified the potential for contamination of available cannabis product with naturally occurring fungi and moulds, as well as pesticides. We will conduct laboratory analysis of cannabis seizures in the WA jurisdiction over a 6 to 12 month period. These analyses will:

(i) measure potency: the ratio of % of the active ingredient THC to % of the chemical cannabidiol (CBD) (n=approx. 200 samples);

(ii) screen for a selected number of contaminants based on those identified in pilot work, (maximum n=100 samples), such as natural contaminants (e.g., moulds, bacteria and fungi), growth enhancers and pesticides; and

(iii) collect, where available, information on type and provenance of each seizure, and related information (e.g., presence of pesticides at seizure) that may prove useful in linking cultivation methods to the outcomes of interest.

Progress

A project meeting was held in Perth in October 2008 to finalise the methodology and logistics of sampling and testing. We are currently awaiting final clearance from the WA Police Service prior to comencing analyses.

Benefits

The project has several potential public health and law enforcement benefits, including:

(i) the provision of important Australian data on the characteristics of cannabis, which can aid in the education of users and health professionals about the health risks associated with market practices.

(ii) the protocol may serve as a model to be expanded to other jurisdictions to provide routine monitoring and to measure longitudinal changes (e.g., in potency) that may result from policy, law enforcement and public health strategies;

(iii) contributing to increasing the capacity of health, education and law enforcement programs to be seen as credible sources of information about the effects of cannabis; and

(iv) intersectoral collaboration between NCPIC (including its consortium members NDARC and NDRI) and the Forensic Science Laboratory at the Chemistry Centre of Western Australia (CCWA).

Funding

National Cannabis Prevention and Information Centre