Overdose - rarely an issue of purity
Heroin is too pure: new users at greatest risk
Heroin is linked to about 40% of all drug deaths in the UK. Although many heroin overdoses- and thus deaths - are often attributed to 'mystery batches' of contaminated or very pure heroin, the fact is that heroin overdoses are rarely the result of either. We know from a range of evidence that there is only a weak relationship between typical purity and fatality rates, with most overdose deaths related to poly-drug use (including alcohol), lowered tolerance (e.g. release from prison and return to using at previous level), and that it occurs predominately among long-term dependent males - a long way from the media portrayal of naive first-time users.
Batches of high purity heroin are not a likely cause of overdose alone and this link is over-emphasised. Users that die from using high purity heroin have usually used more heroin than normal in the preceding 24 hours and/or used other drugs, particularly alcohol.
References
Best, D,. Lan-Ho, M., Zador, D., Darke, S., Bird, S., Strang, J. and Ashton, M. (2000) `Overdosing on Opiates Part 1: Causes', Drug and Alchohol Findings, Winter, 4: 4-7 and 16-20.
Warner-Smith, M., Darke, S., Lynskey, M. and Hall, W. (2001) 'Heroin overdose: causes and consequences', Addiction, 96(8): 1113-1125
Darke, S. and Zador, D. (1996) 'Fatal heroin "overdose" a review', Addiction, 91(12): 1765-1772
