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Synthetic drugs reveal carcinogenic effects


Synthetic cannabinoids, chemically similar to tetrahydrocannabinol, are increasingly being marketed in incense mixtures as ‘legal highs’, yet they remain difficult to chemically identify. Scientists from part of the European ‘SPICE II Plus’ project at MedUni Vienna’s Institute for Cancer Research (Austria) have revealed new evidence to suggest that these chemicals may be carcinogenic. Until now, little investigation has been conducted on the the toxic side effects that can occur following consumption.

The SPICE II Plus project in Europe– now coming to an end– is an international cooperative investigation on synthetic cannabinoids and stimulants, evaluating their associated risks, problematic use and prevention approaches.  The project has been led by the Institute of Medical Jurisprudence at the University Hospital of Freiburg (Germany) as well as the MedUni Vienna and the Goethe University of Frankfurt (Germany), the University of Helsinki (Finland), the Institute of Therapy Research in Munich (Germany).

Between 2005 and 2012, approximately 240 new psychoactive substances disguised as incense blends, bath salts or plant fertiliser, were registered by the European Union’s early warning system. Around 140 of these contained synthetic cannabinoids.

Synthetic cannabinoids can be ordered legally in Europe and trigger similar neurophysiological effects as marijuana by binding to cannabinoid receptors in the human brain.

Siegfried Knasmüller from the Institute for Cancer Research at the MedUni Vienna commented: “The substances are directly active, in other words they are not activated via enzymes that metabolize foreign substances. The respiratory organs and the digestive tract especially are subjected to increased concentrations of these drugs.”

“Our investigations on human cell lines in the laboratory have shown that synthetic cannabinoids, in the high concentrations found in cells in the oral cavity or in the lungs, for example, are likely to trigger damage to the DNA that may have significant consequences for the consumers of such substances. They damage chromosomes, and this is directly associated with cancer.”

Some synthetic cannabinoids can have an effect even in very small quantities; however consumers are unaware of the detailed composition of these synthetic drugs and thus remain unaware of the varying levels of these effects. As a result, there have been cases of poisoning and toxic damage, and in some cases individuals have died from unwanted overdosing.

Whilst legal highs are “flooding the market”, as Knasmüller reports, the findings shed light on both the dangers of the synthetic drug industry and consumer unawareness. Future research will be needed to further explore the carcinogenic effects of synthetic cannabinoids.

Sources: Koller VJ, Zlabinger GJ, Auwärter V, Fuchs S, Knasmueller S. Toxicological profiles of selected synthetic cannabinoids showing high binding affinities to the cannabinoid receptor subtype CB1. Arch. Toxicol. 87 (7): 1287 DOI: 10.1007/s00204-013-1029-1 (2013); The Medical university of Vienna press release