Synthetic Cannabinoids K2 and "Spice"
"Clemson University Professor John Huffman is credited with first synthesizing some of the cannabinoids, such as JWH-018, now used in 'fake pot' substances such as K2. The effects of JWH-018 can be 10 times stronger than those of THC. Dr. Huffman is quoted as saying, 'These things are dangerous—anybody who uses them is playing Russian roulette. They have profound psychological effects. We never intended them for human consumption.'"
Sacco, Lisa N. and Finklea, Kristin M., "Synthetic Drugs: Overview and Issues for Congress," Congressional Research Service (Washington, DC: Library of Congress, October 28, 2011), p. 5.