They were the drug of choice for Jordan Belfort and his debauched clique in The Wolf of Wall Street — and now underground chemists are attempting to manufacture Quaaludes in the UK.
Figures obtained by VICE News under freedom of information laws show that a shipment of the crucial precursor chemical needed to synthesize the addictive sedatives — which are taken with alcohol for recreational use — was seized by UK Border Agency officers in June 2012.
Enough cutting agent to bulk out more than six tons of cocaine was also seized in 2013, the figures show.
Dr Les King, a former member of the Advisory Council for the Misuse of Drugs and precursors expert, said that chemical N-acetylanthranilic acid was only used to make methaqualone — commonly known as Quaaludes.
He added that the one kilogram seizure would make about 3,000 tablets and meant it was likely someone "experimenting" with producing the drug.
Quaaludes were popular in glam rock clubs in Britain in the late 1960s and early '70s, but they were subsequently controlled under the Misuse of Drugs Act and have been all but unheard of in the UK for decades. Their popularity similarly waned in the United States after legal manufacture ended in the early 1980s.
More than one-and-a-half tons of benzocaine was also seized at the border. King said the local anaesthetic was "almost certainly" going to be used to bulk out cocaine, typically at a ratio of one-to-four.
The long list of banned precursor chemicals seized by Border Agency staff over the last few years include those used in the manufacture of amphetamines, the hallucinogenic PCP, and more than 50,000 ephedrine tablets — the precursor chemical for methamphetamine.
Cutting agents for heroin and hundreds of kilograms of solvents for cleaning and purifying drugs were also seized.
King added: "Our experience of illicit chemists in this country is that most of them are pretty incompetent. Most people who set out to make MDMA or amphetamine fail because they're not chemists and they don't really know what they're doing.
"It's not difficult if you're a trained chemist and you know what you're doing, but most of the people who make drugs are not chemists and they're reading from a recipe book. I'm afraid you need a bit of background knowledge as a chemist to know what you're doing, really."
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