I too am quite doubtful about the carcinogenic properties of Safrole. A couple months ago I spent quite a bit of time researching it, looking at medical/university studies & experiments done over the last 60 years with lab animals and such. I just dug up the blip I posted to facebook about it when I was satisfied with my findings, I'll post that below. Basically what I've concluded is that for me, I will make root beer with sassafras and not worry too much more about it. If I'm sharing it with friends I'm under obligation to tell them it has sassafras and what that potentially means. But I'll also tell them why I'm drinking it anyway. It can lead to interesting discussion :) Here's the facebook blip:
Oddly enough, this whole soda-making hobby of mine is inducing an inner reflection on the meaning of life, politics, and conspiracy. I'm also learning a lot about medical science.
The primary flavoring ingredient for Root Beer prior to 1960 was sassafras, a natural ingredient from sassafras roots and bark. In 1960 safrole (the main compound in sassafras) was banned by the FDA because it was found to be carconoginic in lab rats when administered high doses over time. ... Well, I happen to have some sassafras that I would very much like to use to make *real* root beer with, but am of course weary about cancer. Reading some medical science papers though it seems that 1) Test groups didn't really diverge much from the control groups when given small doses. 2) As test animals get bigger it seems less carconoginic (mice almost certainly get cancer, rats often get cancer, dogs don't really get cancer.) 3) It's never been concluded or even really accused of causing cancer in humans, and tests show bad cancer-stuff in rat urine caused by it but *not* in human urine. 4) It's been found, in small doses, to pretty much completely evacuate from both man and rat via urine within 25 hours.
Begin conspiracy theories: 1) It happens to be a fact that safrole can be used to synthesize ecstasy. Perhaps the DEA was involved in the ban? I'd be game for that if the DEA had been around at the time. 2) FDA would rather eliminate natural ingredients in favor of 'controlled' synthetic ingredients. Ehh... I'm kinda on board with this one. 3) Lots of other things have safrole, in smaller quantities, including nutmeg which special provisions were made for because of a full ban's effect on the industry. This actually appears to be simple fact.
And then there's the question of "what is life for?" Is it meant to be lived to the fullest while alive, or closely guarded in order to potentially live the longest? I'm of the belief that pretty much everything causes cancer anymore. Not literally of course, but the idea is that it's pretty much unavoidable and as a society we just keep adding onto the list with new crap we've created or advancements that let us determine that existing crap has always caused cancer. So the question is - do I make some tasty root beer and just be careful to only consume one or two a week and hope it doesn't eventually kill me. Or do I not make tasty root beer and hope I don't get cancer from any number of other things, or killed in an accident having nothing to do with cancer altogether? Hmmm...