Street NMR: Testing times for "bath salts"

Screening for designer drugs

A new NMR screening technique for testing samples of unlisted but illicit street drugs, often sold as "bath salts", can reveal components not normally detected by standard chromatographic methods, according to researchers speaking at the meeting of the American Chemical Society at the end of August.

The advent of so-called "herbal highs", designer and synthetic drugs that are often sold as plant food, incense and bath salts has led in recent years to a wave of hospitalisations and deaths as users seek purportedly legal alternatives to cocaine, ecstasy and marijuana as drugs of abuse. These street products have not necessarily appeared on the radar of the law enforcement authorities and anti-drug agencies, or if they have, their relocation from legal high to controlled substance in legislation has not yet been completed if it is underway at all.

Researchers speaking at the recent ACS meeting in Denver, Colorado, discussed products with such colourful names, as "Ivory Wave" and "Red Dove" that belie the true nature of these substances, which have been synthesised to mimic the narcotic or stimulant effect of various illegal drugs. These products give users a high but are undetectable with the present analytical tests for illicit drugs. One researcher in the UK discussing "legal highs" reported a new method for tracing the source of the substances in so-called "bath salts" another discussed the challenges facing law enforcement and policy makers in regulating synthetic versions of marijuana.

Sniffing out illicit substances

Oliver Sutcliffe of Strathclyde Institute of Pharmacy & Biomedical Sciences, in Glasgow, and his colleagues Niamh Nic Daeid and Osama Khreit, there and at the James Hutton Institute have used isotope ratio mass spectrometry (IRMS) to find out who is making bath salts, a drug product known to cause euphoria, paranoia, anxiety and hallucinations when snorted, smoked or injected, and to trace the chemical companies from which the raw materials were originally obtained.

In previous work, Sutcliffe developed the first pure reference standard for mephedrone, as well as the first reliable liquid chromatography test for the substance, which could be easily run in a typical law enforcement laboratory. He and his colleagues are also now developing a colour-change test kit for the drug, which he says will hopefully be available by the end of 2011.

"With the new method, we could work backwards and trace the substances back to the starting materials," explains Sutcliffe. "The method is successful because the isotopic ratio of the starting material is transferred like a fingerprint through the synthesis,? he explained. He added that he and his colleagues have also developed a rapid, novel NMR screening technique for street samples containing components which cannot normally be detected using standard chromatographic methods.

No time for bathing

"Bath salts" first received attention from the British media in early 2010 when it was revealed that the product, which usually contains mephedrone, is a synthetic version of methcathinone, which is found in illegal Khat, was being sold at relatively low cost on the Internet, on the street and in stores that sell drug paraphernalia. The presence of the chemical cousin of Khat would usually mean that these alternative compounds and their derivatives would automatically be illegal in the UK and the US, which have both banned Khat. However, labelling the products as "not for human consumption," somehow circumvents the legislation governing the supply of medicines for human use.

Nevertheless, bath salts have now been banned in Florida and Louisiana, where abuse was rife and UK officials have imposed a ban on the import of bath salts. This, Sutclfiffe said, will most likely lead to the establishment of clandestine labs in the UK. His research will, however, allow law enforcement to sniff out the bath salts manufacturers.

Robert Lantz from the Rocky Mountain Instrumental Laboratories in Fort Collins, Colorado, discussed the synthetic cannabinoids marketed as incense, spice or "legal marijuana" that lead to a cannabis high but also fail to show up in conventional drug tests.

"We can detect synthetic cannabinoids with modern analytical chemistry techniques, such as liquid or gas chromatography coupled to mass spectrometry, but these assays are too expensive for the 5,000-10,000 urine samples that most drug testing labs receive each day," said Lantz. Most labs screen for drugs with less expensive antibody assays, but because the structures of these substances are so dissimilar, different antibodies would likely be required for many of them, driving up the cost of a more comprehensive test.

The views represented in this article are solely those of the author and do not necessarily represent those of John Wiley and Sons, Ltd.