Drug users are playing a potentially fatal game of snorting mystery white powders.
The Global Drug Survey 2014, conducted in partnership with Fairfax Media, found that of the 5646 New Zealand participants, 5.3 per cent had in the past year snorted or ingested powder without knowing what it was.
Almost half took it at a party, and most said they were given it by someone they trusted.
Three people said they sought emergency medical treatment as a result.
Synthetic cannabis, ecstasy and methamphetamine originate as a white powder.
Environmental Science and Research forensic toxicologist Paul Fitzmaurice said it was impossible for people to know what was in any powder they were taking.
"A white powder is a white powder," he said. "I can show you a white powder that's a synthetic cannabinoid, but there's very little way of telling whether that's a synthetic cannabinoid or whether that's cocaine or methamphetamine until you've analysed it.
"Ultimately, a white powder can be purported or sold as anything you want it to be. Again, there is no quality control."
Small changes to the molecular structure of a drug could turn a recreational drug into something toxic, he said.
"Just a small modification of chemical structure can change something from being low harm or safe, so to speak, to being potentially fatal."
Ecstasy was an example of how Kiwi drug users could never really know what they were getting, he said.
"With regards to ecstasy, they usually come in a pill formulation, and if we go back five to 10 years, a lot of the pills were containing MDMA, which is what ecstasy is," he said.
"Now we find that what purports to be ecstasy in pill formulations contains a lot of other drugs, and they can range from things like simply caffeine ... to some quite novel compounds called cathinones.
"Cathinones are quite a potent stimulant, and there are lots of variants of them.
"There are other products which can be put in there; methamphetamine sometimes.
"Some are a little bit more unusual. I think we have found some pills that contained anabolic steroids and we've even found pills that contain natural erectile dysfunction products similar to Viagra."
It was all a consequence of the black market and its lack of quality control, he said.
"You're in a club, you're buying a pill, you think you're getting ecstasy ... Some of these effects would be quite different than what you'd expect for ecstasy," he said.
"But then again, you'd probably find that you don't go back to your dealer and start to ask questions about what they're supplying and what's in it.
"They won't know. It's just a pill and that's what they're selling."
That was why regulating the legal-high industry was important, so the compounds involved could be controlled and potentially toxic drugs avoided, he said.
- Fairfax Media
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