Michelle:
I'm beginning to think that we can blame almost anything we want for the development of an acoustic neuroma precisely because no one, including doctors and scientific researchers, really knows the actual cause, if one exists. For what it may be worth, I suspect that the genesis of a vestibular schwannoma may not be related to external influences at all, whether they be cell phones, power lines, exposure to toxins, head injuries or what-have-you. However, because I can't disprove any particular theory, I'll acquiesce to the possibility that your hypothesis may be correct.
However, just as many AN patients have never used a cell phone or, like you, used it primarily in the non-AN-affected ear, many of us have never been exposed to hair dye on a regular basis so that theory is not valid when applied to those not in the hair stylist business. I suppose we can all find some possible link between our specific environment and the development of our AN. That might be interesting but would present us with thousands of different 'suspects' and many of them would be non-applicable to other AN patients, making the whole business rather frustrating.
Still, I'm as curious as the next AN patient to know why I developed my tumor. That being the case, I have no objection to any other AN patient seeking answers, even if they may not apply to me or others. I just don't choose to take every suggestion - especially the unproven cell phone 'connection' - all that seriously without some sort of scientific basis for the conclusion, besides other folks 'feelings' But even so, I encourage you to try and follow your theory regarding hair dye and AN development to see where it leads. I don't have a competing theory and for all I know, you might be on to something.
Jim