CHAPTER 24: Measuring Drug Harm

The World Health Organization has long used a system to evaluate the harmfulness of substances when considering which should be included in the 1961 and 1971 United Nations Conventions. By the late 1990s, the European Monitoring Centre for Drugs and Drug Addiction had created a risk assessment protocol for new psychoactive substances. In 2000, the Home Office Advisory Council on the Misuse of Drugs (ACMD) started a programme of risk-assessing 20 substances. This was based on a ‘Delphi’ procedure as used in a recent independent review of the Misuse of Drugs Act 1971 but was also inspired by a scoring system developed by the Dutch government for assessing new substances. This ACMD project showed that there was little correlation between the overall harm of those substances and their legal classification. The findings were further supported by a similar study carried out in the Netherlands as well as a separate analysis using Multi-criteria Decision Analysis and several other independent studies. An entirely different research series carried out over many years determined the lethal toxicity of licit and illicit psychoactive substances. This was variously based on mortality as a function of the number of prescriptions, other measures of availability and the ratio of sole to all mentions of a substance on death certificates. The lethal toxicity of MDMA was similar to that of amphetamine. Heroin had a consistently high lethal toxicity, followed by synthetic cannabinoid receptor agonists, GHB/GBL and certain phenethylamines. Cannabis and benzodiazepines showed the lowest lethal toxicity.