June 6, 2011  -- 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.

JWH-018, Used to Make Spice

Huffman and coworkers began creating a family of cannabinoid chemicals in his laboratory, all of them identified with his initials and a number.

In the summer of 1994, one of the undergraduate students working in his lab created JWH-018, a strong cannabinoid that is easy to make and is now the "JWH" chemical most likely to be found in Spice and other similar products.

"JWH-018 can be made by a halfway decent undergraduate chemistry major in three steps from commercially available materials," said Huffman.

In 2005, Huffman published a paper that included detailed synthetic procedure for making all of the compounds in the JWH class. By then, there were 465.

Within a year, JWH-018 and related substances were being used as recreational drugs in Europe.

"I assume that somebody picked our papers, and saw a way to make some money," said Huffman.

In the past year alone there have been 4,000 calls into poison control centers relating to the drugs. Side effects include heart rate stimulation, blood pressure elevation, anxiety, and hallucinations. "Beyond the acute effects [there] are psychiatric effects that have led individuals to harm themselves, sometimes fatally, and exhibit extreme paranoia and delusions not unlike schizophrenia or other psychoses," said Anthony Scalzo, director of the Missouri Poison Control Center.

The DEA put an emergency ban on the sale of JWH-018 and one other JWH chemical in March, along with three other chemicals commonly found in Spice.

The irony that the government funded the chemicals now being examined by the DEA has not eluded lobbyists for retail stores who sell the Spice and K2.

"The vast majority of these chemicals were created with government financial support," said Dan Francis, Executive Director of the Retail Compliance Association, a coalition of head shops who sell the products.

"It's a three to five billion dollar industry," said Francis, who says that Spice products should be regulated but not outlawed.

NIDA Defends Grant

Huffman says he has his own doubts that prohibition would work, but emphasizes that the people who are selling Spice already know it's bad for humans, based on anecdotal evidence, even if no scientific research has been completed. "The physiological effects of these compounds have never been examined in humans," said Huffman. "There have been a number of cases of people who've committed suicide after using them."

DEA Special Agent Gary Boggs says the agency has to gather enough research on any specific chemical before any substance is controlled. The five chemicals that are now banned are those that the agency found most often in Spice products.

"We're going to continue to look at other chemicals that are out there that are being sold in an effort to circumvent the control of those five substances," said Boggs.

Sen. Chuck Grassley, R.-Iowa, has proposed legislation that would ban all the JWH chemicals so that Spice-makers can't simply switch recipes.

Huffman said that despite the unintended use of his chemicals that have had devastating effects on teens, he is proud of his research, which could potentially lead to the development of new medicines.

"If somebody wants to misuse it, it is the responsibility of the people who misuse it to take responsibility for their own actions," said Huffman, who retired from Clemson in 2010.

A NIDA spokesperson defended the agency's funding for Huffman's research, saying that studying "artificial variations of brain chemicals ... has yielded major research and clinical advances."

Research into cannabinoids, said the spokesperson, "has the potential to usher in the next generation of pain medications," as well as possible treatments for obesity and multiple sclerosis."

"The scientific record demonstrates that the cost of discontinuing the pursuit of potentially life-saving medications, because such compounds could be illegally diverted and abused, would be unacceptably high."

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