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."