Don't use it, it probably contains cinnamon oil, which has really hurt some people who have tried it. It's not good for your teeth (people have reported cavities and a plethora of other health issues with cinnamon oil). Cinnamon oil contains aldehydes which are highly reactive and who knows what they do in your body. Also, the plastics the cinnamon reacted with are most likely not good for your body either, so I would stay away from them. I think the chemist on the forum "Kurt" wrote something about the plastics being very unhealthy if they dissolved in
e-liquid and that he doesn't even use plastic bottles although I would have to dig up the
thread to be sure.