What the Nose Knows - Avery Gilbert [15]
The more I thought about it, the more complications came to mind. Can one replicate the smell of pot without using delta 9-tetrahydrocannibinol (or THC), the psychoactive ingredient? If so, could it still get you busted by a drug-sniffing dog or your homeroom teacher? Would my company be legally liable for the consequences?
THC, and its chemical cousins, are not volatile and are therefore odorless. If a chemist stripped the THC from pot, the result would be genuine-smelling but buzz-less, the psychedelic equivalent of decaffeinated coffee.
When I reach him on the phone, I find Dr. W. James Woodford to be a genial fellow with a Southern accent. He is a fragrance and flavor chemist and the man who invented the first drug pseudoscent. Early in his career, during a stint as a guest researcher at England’s New Scotland Yard, he encountered large samples of contraband cocaine. Woodford knew that the pure cocaine alkaloid was odorless, but when he sniffed it in the evidence room he noticed a distinct aroma. When exposed to air and moisture, cocaine chemically degrades and yields a sweet, prunelike odor. Woodford’s scientific curiosity was piqued, and he traced the scent to a molecule called methyl benzoate. Methyl benzoate is found in flower scents; there’s lots of it in snapdragons and petunias, and some in tuberose and ylang. Perfumers use it all the time, especially in fragrances of the Peau d’Espagne type.
Cocaine is illegal, as are its direct chemical precursors and metabolites. Woodford managed to replicate the scent of cocaine with methyl benzoate and a few other ingredients, all of which are chemically unrelated to cocaine and therefore perfectly legal. Woodford patented his drug pseudoscent formula in 1981, and the government was soon using it to train dogs and drug enforcement personnel. Woodford let the government use it for free. “I didn’t make any money off of it,” he says. Others were not so charitable, and soon an entire industry blossomed. The Sigma-Aldrich chemical supply company, for example, carries Sigma Pseudo™ Narcotic Scent Cocaine formulation, priced at $37.20 for 100 grams. They also sell an LSD formulation and another that mimics the scent of pot. Forensic chemists at Florida International University have created a fake Ecstasy aroma.
Drug dogs trained to find cocaine are, in fact, recognizing the scent of methyl benzoate rather than the cocaine molecule itself. This displacement effect is true for other major targets of drug dogs. Ecstasy gives itself away through the cherry-pie scent of piperonal, and methamphetamine has a characteristic cherry-almond scent from benzaldehyde. So yes, dogs find the drugs, but they should really be called drug-associated-odor-sniffing dogs.
Fragrance clients are nervous about having too real a pot smell for fear of alerting drug dogs and police. What if drug traffickers used these for their own ends? They could flood an airport with pseudoscents and sneak their contraband through while dogs and cops are chasing false leads. It hasn’t happened yet, but Woodford recognizes the danger. “There’s potential for mischief,” he says.
SINCE THC ITSELF is odorless, what gives pot its characteristic aroma? The natural product chemistry of marijuana is complex. Depending on the exact technique used—headspace capture to analyze the scent given off freely by the plant, or steam distillation to extract its essential oils by force—there are anywhere from eighteen to sixty-eight volatile