hi, my mom suffers from a burning sensation inside her mouth almost every day along with fatigue (which is often severe). she works at a scientific institute which uses formaldehyde all the time but recent tests indicate no formaldehyde poisoning.what else could it possibly be? according to her Dr she is in good health except for slightly high cholesterol levels(which is also a puzzle as she is a very health conscious vegetarian) This has been going on for more than a year and recently some of her colleagues have been complaining of strange symptoms too. Do you have any ideas? Also, if her Dr remains at a loss who should she turn to?