We simply do not know. There have been no studies conducted on what effects the synthetic cannabinoids may have on the body and brain. Of course, smoking any substance could have negative affects on the lungs, but we have no scientific evidence concerning the specific use of these fake marijuana products.
We do have a warning from one of the scientists who helped develop the JWH-018 chemical. While studying the effects of pharmaceuticals on the brain, a student of John Huffman, Clemson University research professor of chemistry, discovered the chemical JWH-018, also known by the name 1-Pentyl-3-(1-naphthoyl)indole.
“The problem with JWH-018 is that absolutely nothing is known regarding its toxicity or metabolites,” Huffman warned. “Therefore, it is potentially dangerous and should not be used.”