BLAME FOR HEROIN DEATHS TOO OFTEN PLACED ON PURITY

By Julie Delvecchio

Fatal heroin overdoses cannot be blamed on purity alone, according to new
research which warns that using drugs in combination plays a crucial role
in overdose deaths.

A joint study by the National Drug and Alcohol Research Centre (NDARC) and
the NSW Bureau of Crime Statistics and Research reveals that alcohol and
tranquillisers, or benzodiazepines, contribute significantly to heroin
overdoses.

Benzodiazepines, such as Rohypnol and Valium, are central nervous system
(CNS) depressants.

Purity explains only onequarter of fatal heroin overdoses, according to
the study, which examined the purity of street heroin and fatal overdoses
in southwest Sydney.

The study, to be presented at the NDARC annual symposium in Sydney
tomorrow, examined 300 heroin samples seized from the streets of
Cabramatta. They were taken fortnightly from February 1993 to January 1995,
and compared with the 61 overdose deaths over the same period. This allowed
researchers to examine the degree to which purity impacts on overdose deaths.

The study's head researcher, Dr Shane Darke, said purity was not the main
reason fatal heroin overdose rates vary.

"In my opinion the single most important factor [in heroin overdose] is
using drugs in combination," Dr Darke said.

"There just seems to be this myth that purity is what kills people. It's a
simple explanation but simple explanations are not necessarily right."

Dr Darke said alcohol was detected in onethird of cases at autopsy. A
further onethird had taken benzodiazepines, highlighting that a normally
tolerated dose of heroin may prove fatal when combined with such substances.

The average purity of the heroin samples was 59 per cent, although purity
varied greatly, from 13 per cent to 80 per cent.

The mean age of fatal overdoses was 29 years, and 87 per cent were men.
Almost all were classified as longterm, dependent heroin users.

"Such longterm older heroin users would be expected to have considerable
tolerance to variations in opioid purity," the study found.

It warned that focusing education programs solely on purity was "not only
factually incorrect, but clinically dangerous".

"Heroin users need to be aware that while purity is a factor, it is not the
only factor in heroin overdose," the study concluded.

"The role of other CNS depressants in "heroin' overdoses is one factor that
should be emphasised."

Dr Darke said there may be arguments for legalising heroin, such as crime
or moral issues, "but it's naive to believe that to legalise and to control
purity would stop overdose deaths".