Is your city water Fluoridated or chlorinated? Then this is very likely your main source. Bromide fumes from your car, mattress & carpeting could be at fault. Wrap your mattress in a zipper bag to seal in the bromide fumes. Replace your carpeting with hardwood flooring. Do you eat bread? Switch to bromide free bread. Even bottled water contains fluoride. Switch to distilled water and get a water distiller for your home.