A Doctors advice should be sought before using this and any supplemental dietary product
There is a study that has attempted to look at this, undertaken by some of my colleagues at University of Bristol (full disclosure, I am a member of the same research group as two of the authors of this paper)
When I acquire one that I really love its difficult for me, because I think about who does one pass this on to
#4 i use a POWERMATIC electric cigg injector, ive had it for about 5 months with no issues, i'd stronglly suggest you look into getting one of these,,,,vs/....them manual machines, i'll allways have my electric machine, and if it goes down i'll get another one, well worth the money,,, you cant go wrong with the name brand POWERMATIC, #5 I've used the PowerMatic for a few years its bullet proof
It can therefore also explain the decision of the German authorities to combine graphical and textual warnings together for getting the best impact on the target audience