ONE-FIFTH of so-called "legal highs" contain controlled drugs, according to new forensic studies done by police in a new drive to identify their chemical content.

The tests also found them sold in shops in Glasgow and Edinburgh contained potentially fatal substances.

Officers at the Scottish Crime and Drug Enforcement Agency have been running an "overt purchasing" scheme in which police buy substances sold as legal highs from head shops – purveyors of drug paraphernalia and herbal remedies.

Several of the "legal high" tablets tested contained paramethoxymethylamphetamine (PMMA), which is believed to have been responsible for at least 19 deaths in Europe since summer 2010.

Officers revealed that, since a warning about PMMA had been issued in July last year, the substance had been found to be involved in a number of drug-related deaths in Scotland.

Class A drug PMMA is said to have similar effects to the more commonly known ecstasy ingredient MDMA. However, some users believe it is less potent, meaning they end up taking higher doses.

Detective Inspector Tommy Crombie, from the SCDEA and drugs co-ordinator at the Association of Chief Police Officers in Scotland, said: "The lab has a bank of reference materials to compare traditional illicit substances but when a new psychoactive substance is found there is nothing to compare it against. What we are doing is collecting a range of samples to compare and index the chemical compounds.

"There are a number of places we can source them, including the internet and in head shops, and we have been buying them on an overt basis. Overall, 20% of the samples analysed contained drugs class A, B or C.

"These substances all come in very colourful wrappings and are made to look very attractive to young people but there is no validation or identification of what they contain.

"The websites providing them look very plausible and respectable. For those making them it all comes down to profit margins, risk and demand. Yet user forums talk about tongues, eyes, and noses bleeding as a result. These things are being made in a tin hut in an industrial estate."

Thirty seven products were purchased from independent retail establishments in Scotland as part of the overt testing.

These were analysed by the Scottish Police Services Authority Forensic Services Glasgow laboratory. It found that three contained PMMA, several contained banned doping drugs, and several cannabinoid receptor agonists which were made Class B drugs in 2009.

One packet costing £34.99 contained just dried herbs. Others contained lignocaine – an anaesthetic used in dentistry known to cause adverse cardiovascular system reactions.

The tests also identified desoxypipradrol, first found in Scotland in samples in 2010. It was linked to several incidents in which people under the influence of the drug were admitted to hospital with severe side- effects.

Mr Crombie added: "This is very much a growing problem. We find young people who would not normally buy controlled drugs using them even though they have no idea what they contain.

"With these so-called legal highs you can just walk in. I am not saying the head shops are all knowingly selling substances which might be controlled drugs and at best will be harmful."

In the new year the new legislation allowing for temporary banning orders for new psychoactive drugs will come into force. It will make it illegal for people to be involved in the supply of newly banned substances.

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