http://www.wrdw.com/politics/headlines/94874874.html Oh well....and all spice is different. Some have less negative effect than others. Bud is king! lol
A great vendor differentiates themselves by lab testing all of their product for this very reason. When properly collected, herbal incense can be a fine way to relax at the end of an evening.
I hate spice and think you should avoid it if at all possible, but the only spice that I've found with a reaction similar to cannabis was Black Mamba. I'm pretty sure its not sold anymore though.