The U.S. government might not be scrambling to ban "Spice," the "legal marijuana" that's sending teens to emergency rooms across the country, if it hadn't helped invent the drug in the first place.
As detailed in an ABC News "20/20" investigation, Spice, K2 and other substances in a new wave of legal designer drugs are widely available at convenience stores and suburban malls though they've been responsible for more than 4,000 calls to the nation's poison control centers in the past year.
WATCH the "20/20" report
The Drug Enforcement Administration has placed an emergency ban on a handful of the chemicals that are used to make Spice, but there are hundreds more chemicals readily available – most of them designed by Clemson University scientist John W. Huffman using a grant from the government's National Institute for Drug Abuse (NIDA).
Over the course of a decade, Huffman created nearly 500 "cannabinoids" that affect the brain in a much more powerful way than THC, the active component in marijuana. About five years ago, entrepreneurs began spraying the chemicals he invented on plant matter to create "legal marijuana."
"I figured that somewhere along the line, some enterprising individual would try to smoke it," Huffman told ABC News in a recent interview. But, said Huffman, given the dangers of the chemicals, anybody show smokes them "is incredibly foolish."
"They're playing Russian roulette," he said. "I mean, it's just like taking a pistol with one bullet in it and spinning the chamber and holding it to your head and pulling the trigger."
Huffman first obtained the NIDA grant in 1984, which ultimately totaled $2,564,000, when the government asked him to synthesize the human metabolite of THC.
In the 1990s, NIDA asked him to switch gears, and either develop medicine or study the "cannabinoid receptors" in the brain, which respond to marijuana.