I could die tomorrow. I have a fairly broad understanding of chemistry, neurology, and physiology too. I suspect that JWH-018 is in fact carcinogenic (I smoke JWHxxx's instead of marijuana or cigarettes, obviously nothing is better for my body but hey tradeoffs) whilst some others may be more physically benign or maybe even have other unknown negative effects. I know that the effects of the JWH-xxx series are unusually mentally manifesting for a cannabinoid mimetic, that is what I mostly seek out of the concept of being high.
Most of the people in here don't fit the contour of the long term risks I suspect (who knows??) that some indole based mimetics might bring with physical evidence here in reality eventually. I might be the future poster child myself, you guys are talking about medicating yourselves by all sorts of known addictive and deadly drugs with overdose ranges marked and addiction potential (Like me!) in the name of "curing" yourself from a material object that was in you quite a long time ago with no imprint that any real doctors can find.
I smoke ~200mg of JWH-250 a day currently, I will report on the side of something physically going wrong if it ever did arise. I just don't eat hype and find most people to have serious attribution problems that stick out sometimes.
ALL HEIL JWH-018